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Sample records for dual functional properties

  1. Dual-functional composite with anticoagulant and antibacterial properties based on heparinized silk fibroin and chitosan.

    PubMed

    Wang, Jianglin; Hu, Wei; Liu, Qun; Zhang, Shengmin

    2011-07-01

    Heparinized biomaterials exhibit great anticoagulant properties. However, they promote proliferation of Staphylococcus aureus (S. aureus) and therefore cause infection within the bloodstream upon implantation in vivo. In the present study, an interesting dual-functional composite with anticoagulant and antibacterial properties based on heparinized silk fibroin and chitosan was synthesized. First, heparin was grafted onto the silk fibroin by covalent immobilization with N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) and N-hydroxysuccinimide (NHS). All data gathered from Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and elemental analysis (EA) indicated that the heparin was successfully immobilized onto the silk fibroin. The dual-functional composite of heparinized silk fibroin and chitosan was then fabricated by a blending method. The anticoagulant activity of the heparinized materials was evaluated using the prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT). The results showed that both heparinized silk fibroin and the composite material exhibited better hemocompatibility in comparison with single silk fibroin or chitosan. The antibacterial property of the materials was investigated by the pour-plate method. Results further suggested that the composite antibacterial property with respect to S. aureus was significantly enhanced. The dual-functionality of the composite material may supply a potential choice in blood contact devices. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Effect of dual modification of sonication and γ-irradiation on physicochemical and functional properties of lentil (Lens culinaris L.) starch.

    PubMed

    Majeed, Toiba; Wani, Idrees Ahmed; Hussain, Peerzada Rashid

    2017-08-01

    Starch isolated from lentil was subjected to two treatments namely sonication and, a dual treatment of sonication and irradiation at a dose of 5kGy. Lentil yielded 26.12±1.56g starch/100g of lentil. Chemical composition of native starch revealed 7.83±0.28% moisture, 0.23±0.30% protein, 0.35±0.05% fat and 0.10±0.00% ash. The results revealed that pasting properties of lentil starch were not affected upon sonication. However, these decreased significantly (p≤0.05) upon dual treatments. Amylose content of native starch was 31.16±1.80g/100g which showed a decrease upon sonication and dual treatments. Sonication and dual treatments (sonication and irradiation) decreased hunter 'L' value while 'a' and 'b' values showed an increase. Syneresis decreased more or less insignificantly upon sonication. However, a significant decrease in syneresis was observed after 120h storage following dual treatments. Sonication did not decrease the functional properties significantly while as dual treatment induced a significant decrease in functional properties. FT-IR analysis revealed a decrease in the intensities of OH, CH and OC stretches and CH 2 bending upon sonication and dual treatments. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Magnetic Nanoparticles with Dual Functional Properties: Drug Delivery and Magnetic Resonance Imaging

    PubMed Central

    Jain, Tapan K.; Richey, John; Strand, Michelle; Leslie-Pelecky, Diandra L.; Flask, Chris; Labhasetwar, Vinod

    2008-01-01

    There is significant interest in recent years in developing MNPs having multifunctional characteristics with complimentary roles. In this study, we investigated the drug delivery and magnetic resonance imaging (MRI) properties of our novel oleic acid-coated iron-oxide and pluronic-stabilized magnetic nanoparticles (MNPs). The drug incorporation efficiency of doxorubicin and paclitaxel (alone or in combination) in MNPs was 74–95%; the drug release was sustained and the incorporated drugs had marginal effects on physical (size and zeta potential) or magnetization properties of the MNPs. The drugs in combination incorporated in MNPs demonstrated highly synergistic antiproliferative activity in breast cancer cells. The T2 relaxivity (r2) was higher for our MNPs than Feridex IV, whereas the T1 relaxivity (r1) was better for Feridex IV than for our MNPs, suggesting greater sensitivity of our MNPs than Feridex IV in T2 weighted imaging. The circulation half-life (t1/2), determined from the changes in the MRI signal intensity in carotid arteries in mice, was longer for our MNPs than Feridex IV (t1/2 = 31.2 vs 6.4 min). MNPs with combined characteristics of MRI and drug delivery could be of high clinical significance in the treatment of various disease conditions. PMID:18649936

  4. Dual function conducting polymer diodes

    DOEpatents

    Heeger, Alan J.; Yu, Gang

    1996-01-01

    Dual function diodes based on conjugated organic polymer active layers are disclosed. When positively biased the diodes function as light emitters. When negatively biased they are highly efficient photodiodes. Methods of preparation and use of these diodes in displays and input/output devices are also disclosed.

  5. Magnesium acceptor in gallium nitride. II. Koopmans-tuned Heyd-Scuseria-Ernzerhof hybrid functional calculations of its dual nature and optical properties

    NASA Astrophysics Data System (ADS)

    Demchenko, D. O.; Diallo, I. C.; Reshchikov, M. A.

    2018-05-01

    The problem of magnesium acceptor in gallium nitride is that experimental photoluminescence measurements clearly reveal a shallow defect state, while most theoretical predictions favor a localized polaronic defect state. To resolve this contradiction, we calculate properties of magnesium acceptor using the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional, tuned to fulfill the generalized Koopmans condition. We test Koopmans tuning of HSE for defect calculations in GaN using two contrasting test cases: a deep state of gallium vacancy and a shallow state of magnesium acceptor. The obtained parametrization of HSE allows calculations of optical properties of acceptors using neutral defect-state eigenvalues, without relying on corrections due to charged defects in periodic supercells. Optical transitions and vibrational properties of M gGa defect are analyzed to bring the dual (shallow and deep) nature of this defect into accord with experimental photoluminescence measurements of the ultraviolet band in Mg-doped GaN samples.

  6. 2-Deoxy-D-Glucose Modified Magnetic Nanoparticles with Dual Functional Properties: Nanothermotherapy and Magnetic Resonance Imaging.

    PubMed

    Zhao, Lingyun; Zheng, Yajing; Yan, Hao; Xie, WenSheng; Sun, Xiaodan; Li, Ning; Tang, Jintian

    2016-03-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) with appropriate surface chemistry have attracted wild attention in medical and biological application because of their current and potential usefulness such as magnetic resonance imaging (MRI) contrast enhancement, magnetic mediated hyperthermia (MMH), immunoassay, and in drug delivery, etc. In this study, we investigated the MRI contrast agents and MMH mediators properties of the novel 2-deoxy-D-glucose (2-DG) modified SPIONs. As a non-metabolizable glucose analogue, 2-DG can block glycolysis and inhibits protein glycosylation. Moreover, SPIONs coated with 2-DG molecules can be particularly attractive to resource-hungry cancer cells, therefore to realize the targeting strategy for the SPIONs. SPIONs with amino silane as the capping agent for amino-group surface modification were synthesized by the chemical co-precipitation method with modification. Glutaraldehyde was further applied as an activation agent through which 2-DG was conjugated to the amino-coated SPIONs. Physicochemical characterizations of the 2-DG-SPIONs, such as surface morphology, surface charge and magnetic properties were investigated by Transmission Electron Microscopy (TEM), ζ-Potential and Vibrating Sample Magnetometer (VSM), etc. Magnetic inductive heating characteristics of the 2-DG-SPIONs were analyzed by exposing the SPIONs suspension (magnetic fluid) under alternative magnetic field (AMF). U-251 human glioma cells with expression of glucose transport proteins type 1 and 3 (GLUT1 and GLUT 3), and L929 murine fibroblast cell as negative control, were employed to study the effect of 2-DG modification on the cell uptake for SPIONs. TEM images for ultra-thin sections as well as ICP-MS were applied to evaluate the SPIONs internalization within the cells. In vitro MRI was performed after cells were co-incubated with SPIONs and the T2 relaxation time was measured and compared. The results demonstrate that 2-DG-SPIONs were supermagnetic and in

  7. Unraveling Executive Functioning in Dual Diagnosis.

    PubMed

    Duijkers, Judith C L M; Vissers, Constance Th W M; Egger, Jos I M

    2016-01-01

    In mental health, the term dual-diagnosis is used for the co-occurrence of Substance Use Disorder (SUD) with another mental disorder. These co-occurring disorders can have a shared cause, and can cause/intensify each other's expression. Forming a threat to health and society, dual-diagnosis is associated with relapses in addiction-related behavior and a destructive lifestyle. This is due to a persistent failure to control impulses and the maintaining of inadequate self-regulatory behavior in daily life. Thus, several aspects of executive functioning like inhibitory, shifting and updating processes seem impaired in dual-diagnosis. Executive (dys-)function is currently even seen as a shared underlying key component of most mental disorders. However, the number of studies on diverse aspects of executive functioning in dual-diagnosis is limited. In the present review, a systematic overview of various aspects of executive functioning in dual-diagnosis is presented, striving for a prototypical profile of patients with dual-diagnosis. Looking at empirical results, inhibitory and shifting processes appear to be impaired for SUD combined with schizophrenia, bipolar disorder or cluster B personality disorders. Studies involving updating process tasks for dual-diagnosis were limited. More research that zooms in to the full diversity of these executive functions is needed in order to strengthen these findings. Detailed insight in the profile of strengths and weaknesses that underlies one's behavior and is related to diagnostic classifications, can lead to tailor-made assessment and indications for treatment, pointing out which aspects need attention and/or training in one's self-regulative abilities.

  8. Probing the Structures and Electronic Properties of Dual-Phosphorus-Doped Gold Cluster Anions (AunP-2, n = 1–8): A Density functional Theory Investigation

    SciTech Connect

    Xu, Kang-Ming; Huang, Teng; Liu, Yi-Rong

    2015-07-29

    The geometries of gold clusters doped with two phosphorus atoms, (AunP-2, n = 1–8) were investigated using density functional theory (DFT) methods. Various two-dimensional (2D) and three-dimensional (3D) structures of the doped clusters were studied. The results indicate that the structures of dual-phosphorus-doped gold clusters exhibit large differences from those of pure gold clusters with small cluster sizes. In our study, as for Au6P-2, two cis–trans isomers were found. The global minimum of Au8P-2 presents a similar configuration to that of Au-20, a pyramid-shaped unit, and the potential novel optical and catalytic properties of this structure warrant further attention. Themore » higher stability of AunP-2 clusters relative to Au-n+2 (n = 1–8) clusters was verified based on various energy parameters, and the results indicate that the phosphorus atom can improve the stabilities of the gold clusters. We then explored the evolutionary path of (n = 1–8) clusters. We found that AunP-2 clusters exhibit the 2D–3D structural transition at n = 6, which is much clearer and faster than that of pure gold clusters and single-phosphorus-doped clusters. The electronic properties of AunP-2 (n = 1–8) were then investigated. The photoelectron spectra provide additional fundamental information on the structures and molecular orbitals shed light on the evolution of AunP-2 (n = 1–8). Natural bond orbital (NBO) described the charge distribution in stabilizing structures and revealed the strong relativistic effects of the gold atoms.« less

  9. Dual little strings and their partition functions

    NASA Astrophysics Data System (ADS)

    Bastian, Brice; Hohenegger, Stefan; Iqbal, Amer; Rey, Soo-Jong

    2018-05-01

    We study the topological string partition function of a class of toric, double elliptically fibered Calabi-Yau threefolds XN ,M at a generic point in the Kähler moduli space. These manifolds engineer little string theories in five dimensions or lower and are dual to stacks of M5-branes probing a transverse orbifold singularity. Using the refined topological vertex formalism, we explicitly calculate a generic building block which allows us to compute the topological string partition function of XN ,M as a series expansion in different Kähler parameters. Using this result, we give further explicit proof for a duality found previously in the literature, which relates XN ,M˜XN',M' for N M =N'M' and gcd (N ,M )=gcd (N',M') .

  10. Dual functional star polymers for lubricants

    DOE PAGES

    Cosimbescu, Lelia; Robinson, Joshua W.; Zhou, Yan; ...

    2016-09-12

    Star-shaped poly(alkyl methacrylate)s (PAMAs) with a three arm architecturewere designed, prepared and their performance as a dual additive (viscosity index improver and friction modifier) for engine oils was evaluated. Furthermore, the structure property relationships between the macromolecular structure and lubricant performance were studied, such as molecular weight and polarity effects on the viscosity index. Several copolymers of dodecylmethacrylate with polar methacrylates in various amounts and various topologies, were synthesized as model compounds. Star polymers with a polar content of at least 10% in a block or tapered block topology effectively reduced the friction coefficient in both mixed and boundary lubricationmore » regimes. Furthermore, a polar content of 20% was efficient in reducing friction in both random and block topologies.« less

  11. Experimental and density functional theory (DFT): A dual approach to probe the key properties of creatininium L-tartrate monohydrate single crystal for nonlinear optical applications

    NASA Astrophysics Data System (ADS)

    Thirumurugan, R.; Babu, B.; Anitha, K.; Chandrasekaran, J.

    2017-12-01

    A novel organic nonlinear optical (NLO) material, creatininium L-tartrate monohydrate (CTM) was synthesized and it was grown as single crystals with optical quality. 1H and 13C NMR spectral studies were performed and molecular structure of synthesized CTM compound was confirmed. Single crystal X-ray diffraction (SXRD) analysis confirmed that CTM was crystallized in orthorhombic system with non-centrosymmetric (NCS), P212121, space group. The grown crystal exhibited admirable properties such as second harmonic generation efficiency (SHG) (1.9 times KDP), and high laser damage threshold (LDT) value of 3.7 GW cm-2. CTM crystal displayed high transparency (∼60%) in the visible and near-IR region with low cut-off wavelength at 249 nm. Photoluminescence study confirmed blue wavelength emission (∼463 nm) of grown crystal. Thermal and mechanical behaviours have been successfully analysed for grown crystals. The dielectric studies were carried out for grown crystal as a function of frequencies at different temperatures. Hirshfeld surface and fingerprint plots provided the percentage of individual interactions contributed by each atom. Moreover, density functional theory (DFT) calculations have been employed to probe the frontier molecular orbitals (FMOs) and first hyperpolarizability (β) analysis of the optimized CTM structure. These results validated CTM as a suitable NLO candidate and were discussed in this work.

  12. Dual-functional biomimetic materials: nonfouling poly(carboxybetaine) with active functional groups for protein immobilization.

    PubMed

    Zhang, Zheng; Chen, Shengfu; Jiang, Shaoyi

    2006-12-01

    We introduce a dual-functional biocompatible material based on zwitterionic poly(carboxybetaine methacrylate) (polyCBMA), which not only highly resists protein adsorption/cell adhesion, but also has abundant functional groups convenient for the immobilization of biological ligands, such as proteins. The dual-functional properties are unique to carboxybetaine moieties and are not found in other nonfouling moieties such as ethylene glycol, phosphobetaine, and sulfobetaine. The unique properties are demonstrated in this work by grafting a polyCBMA polymer onto a surface or by preparing a polyCBMA-based hydrogel. PolyCBMA brushes with a thickness of 10-15 nm were grafted on a gold surface using the surface-initiated atom transfer radical polymerization method. Protein adsorption was analyzed using a surface plasmon resonance sensor. The surface grafted with polyCBMA very largely prevented the nonspecific adsorption of three test proteins, that is, fibrinogen, lysozyme, and human chorionic gonadotropin (hCG). The immobilization of anti-hCG on the surface resulted in the specific binding of hCG while maintaining a high resistance to nonspecific protein adsorption. Transparent polyCBMA-based hydrogel disks were decorated with immobilized fibronectin. Aortic endothelial cells did not bind to the polyCBMA controls, but appeared to adhere well and spread on the fibronectin-modified surface. With their dual functionality and biomimetic nature, polyCBMA-based materials are very promising for their applications in medical diagnostics, biomaterials/tissue engineering, and drug delivery.

  13. Dual Function of Glucosamine in Gelatin/Hyaluronic Acid Cryogel to Modulate Scaffold Mechanical Properties and to Maintain Chondrogenic Phenotype for Cartilage Tissue Engineering.

    PubMed

    Chen, Chih-Hao; Kuo, Chang-Yi; Wang, Yan-Jie; Chen, Jyh-Ping

    2016-11-23

    Glucosamine (GlcN) fulfills many of the requirements as an ideal component in scaffolds used in cartilage tissue engineering. The incorporation of GlcN in a gelatin/hyaluronic acid (GH) cryogel scaffold could provide biological cues in maintaining the phenotype of chondrocytes. Nonetheless, substituting gelatin with GlcN may also decrease the crosslinking density and modulate the mechanical properties of the cryogel scaffold, which may be beneficial as physical cues for chondrocytes in the scaffold. Thus, we prepared cryogel scaffolds containing 9% GlcN (GH-GlcN9) and 16% GlcN (GH-GlcN16) by carbodiimide-mediated crosslinking reactions at -16 °C. The crosslinking density and the mechanical properties of the cryogel matrix could be tuned by adjusting the content of GlcN used during cryogel preparation. In general, incorporation of GlcN did not influence scaffold pore size and ultimate compressive strain but increased porosity. The GH-GlcN16 cryogel showed the highest swelling ratio and degradation rate in hyaluronidase and collagenase solutions. On the contrary, the Young's modulus, storage modulus, ultimate compressive stress, energy dissipation level, and rate of stress relaxation decreased by increasing the GlcN content in the cryogel. The release of GlcN from the scaffolds in the culture medium of chondrocytes could be sustained for 21 days for GH-GlcN16 in contrast to only 7 days for GH-GlcN9. In vitro cell culture experiments using rabbit articular chondrocytes revealed that GlcN incorporation affected cell proliferation, morphology, and maintenance of chondrogenic phenotype. Overall, GH-GlcN16 showed the best performance in maintaining chondrogenic phenotype with reduced cell proliferation rate but enhanced glycosaminoglycans (GAGs) and type II collagen (COL II) secretion. Quantitative real-time polymerase chain reaction also showed time-dependent up-regulation of cartilage-specific marker genes (COL II, aggrecan and Sox9) for GH-GlcN16. Implantation of

  14. Dual-cycle dielectrophoretic collection rates for probing the dielectric properties of nanoparticles

    PubMed Central

    Bakewell, David J; Holmes, David

    2013-01-01

    A new DEP spectroscopy method and supporting theoretical model is developed to systematically quantify the dielectric properties of nanoparticles using continuously pulsed DEP collection rates. Initial DEP collection rates, that are dependent on the nanoparticle dielectric properties, are an attractive alternative to the crossover frequency method for determining dielectric properties. The new method introduces dual-cycle amplitude modulated and frequency-switched DEP (dual-cycle DEP) where the first collection rate with a fixed frequency acts as a control, and the second collection rate frequency is switched to a chosen value, such that, it can effectively probe the dielectric properties of the nanoparticles. The application of the control means that measurement variation between DEP collection experiments is reduced so that the frequency-switched probe collection is more effective. A mathematical model of the dual-cycle method is developed that simulates the temporal dynamics of the dual-cycle DEP nanoparticle collection system. A new statistical method is also developed that enables systematic bivariate fitting of the multifrequency DEP collection rates to the Clausius–Mossotti function, and is instrumental for determining dielectric properties. A Monte-Carlo simulation validates that collection rates improve estimation of the dielectric properties, compared with the crossover method, by exploiting a larger number of independent samples. Experiments using 200 nm diameter latex nanospheres suspended in 0.2 mS/m KCl buffer yield a nanoparticle conductivity of 26 mS/m that lies within 8% of the expected value. The results show that the dual-frequency method has considerable promise particularly for automated DEP investigations and associated technologies. PMID:23172363

  15. Dual-modality imaging of function and physiology

    NASA Astrophysics Data System (ADS)

    Hasegawa, Bruce H.; Iwata, Koji; Wong, Kenneth H.; Wu, Max C.; Da Silva, Angela; Tang, Hamilton R.; Barber, William C.; Hwang, Andrew B.; Sakdinawat, Anne E.

    2002-04-01

    Dual-modality imaging is a technique where computed tomography or magnetic resonance imaging is combined with positron emission tomography or single-photon computed tomography to acquire structural and functional images with an integrated system. The data are acquired during a single procedure with the patient on a table viewed by both detectors to facilitate correlation between the structural and function images. The resulting data can be useful for localization for more specific diagnosis of disease. In addition, the anatomical information can be used to compensate the correlated radionuclide data for physical perturbations such as photon attenuation, scatter radiation, and partial volume errors. Thus, dual-modality imaging provides a priori information that can be used to improve both the visual quality and the quantitative accuracy of the radionuclide images. Dual-modality imaging systems also are being developed for biological research that involves small animals. The small-animal dual-modality systems offer advantages for measurements that currently are performed invasively using autoradiography and tissue sampling. By acquiring the required data noninvasively, dual-modality imaging has the potential to allow serial studies in a single animal, to perform measurements with fewer animals, and to improve the statistical quality of the data.

  16. Polymeric blends for sensor and actuation dual functionality

    NASA Technical Reports Server (NTRS)

    St. Clair, Terry L. (Inventor); Harrison, Joycelyn S. (Inventor); Su, Ji (Inventor); Ounaies, Zoubeida (Inventor)

    2004-01-01

    The invention described herein supplies a new class of electroactive polymeric blend materials which offer both sensing and actuation dual functionality. The blend comprises two components, one component having a sensing capability and the other component having an actuating capability. These components should be co-processable and coexisting in a phase separated blend system. Specifically, the materials are blends of a sensing component selected from the group consisting of ferroelectric, piezoelectric, pyroelectric and photoelectric polymers and an actuating component that responds to an electric field in terms of dimensional change. Said actuating component includes, but is not limited to, electrostrictive graft elastomers, dielectric electroactive elastomers, liquid crystal electroactive elastomers and field responsive polymeric gels. The sensor functionality and actuation functionality are designed by tailoring the relative fraction of the two components. The temperature dependence of the piezoelectric response and the mechanical toughness of the dual functional blends are also tailored by the composition adjustment.

  17. Development of engineering components having dual functionality

    NASA Astrophysics Data System (ADS)

    Thompson, L. D.; Waldbusser, R.; Pratt, E.

    2000-05-01

    This paper describes the engineering research and development of a smart aircraft bolt designed for high-tension wing attachment applications on USAF C-130 cargo planes. The bolt is a load-carrying structural component as well as serving as a damage sensor. The bolt material choice is TRIP (Transformation Induced Plasticity) steel; high-strength, metastable austenitic steel that gradually and irreversibly transforms to martensite during deformation. The martensite is ferromagnetic whereas the parent austenite phase is paramagnetic, having no significant ferromagnetic response. The ferromagnetic signature of the bolt can be correlated to the peak deformation strain and further correlated with the peak damage state. Stress-assisted phase transformations occur within the elastic regime while strain-induced transformations occur in the post-yield regime. Both transformation variants produce easily detected signals that can be readily monitored. A review of the nature of TRIP steel materials, their properties and behavior, and the smart bolt design approach is presented with examples of the quantitative output obtained during simulated laboratory testing. A brief discussion of the detection electronics and interrogation system is provided to familiarize the audience with the technical issues encompassing this technology. Preliminary results from field testing and service experience are reviewed.

  18. Integrated process and dual-function catalyst for olefin epoxidation

    DOEpatents

    Zhou, Bing; Rueter, Michael

    2003-01-01

    The invention discloses a dual-functional catalyst composition and an integrated process for production of olefin epoxides including propylene oxide by catalytic reaction of hydrogen peroxide from hydrogen and oxygen with olefin feeds such as propylene. The epoxides and hydrogen peroxide are preferably produced simultaneously in situ. The dual-functional catalyst comprises noble metal crystallites with dimensions on the nanometer scale (on the order of <1 nm to 10 nm), specially dispersed on titanium silicalite substrate particles. The dual functional catalyst catalyzes both the direct reaction of hydrogen and oxygen to generate hydrogen peroxide intermediate on the noble metal catalyst surface and the reaction of the hydrogen peroxide intermediate with the propylene feed to generate propylene oxide product. Combining both these functions in a single catalyst provides a very efficient integrated process operable below the flammability limits of hydrogen and highly selective for the production of hydrogen peroxide to produce olefin oxides such as propylene oxide without formation of undesired co-products.

  19. Dual-function antibacterial surfaces for biomedical applications.

    PubMed

    Yu, Qian; Wu, Zhaoqiang; Chen, Hong

    2015-04-01

    Bacterial attachment and the subsequent formation of biofilm on surfaces of synthetic materials pose a serious problem in both human healthcare and industrial applications. In recent decades, considerable attention has been paid to developing antibacterial surfaces to reduce the extent of initial bacterial attachment and thereby to prevent subsequent biofilm formation. Briefly, there are three main types of antibacterial surfaces: bactericidal surfaces, bacteria-resistant surfaces, and bacteria-release surfaces. The strategy adopted to develop each type of surface has inherent advantages and disadvantages; many efforts have been focused on the development of novel antibacterial surfaces with dual functionality. In this review, we highlight the recent progress made in the development of dual-function antibacterial surfaces for biomedical applications. These surfaces are based on the combination of two strategies into one system, which can kill attached bacteria as well as resisting or releasing bacteria. Perspectives on future research directions for the design of dual-function antibacterial surfaces are also provided. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  20. Orbifold E-functions of dual invertible polynomials

    NASA Astrophysics Data System (ADS)

    Ebeling, Wolfgang; Gusein-Zade, Sabir M.; Takahashi, Atsushi

    2016-08-01

    An invertible polynomial is a weighted homogeneous polynomial with the number of monomials coinciding with the number of variables and such that the weights of the variables and the quasi-degree are well defined. In the framework of the search for mirror symmetric orbifold Landau-Ginzburg models, P. Berglund and M. Henningson considered a pair (f , G) consisting of an invertible polynomial f and an abelian group G of its symmetries together with a dual pair (f ˜ , G ˜) . We consider the so-called orbifold E-function of such a pair (f , G) which is a generating function for the exponents of the monodromy action on an orbifold version of the mixed Hodge structure on the Milnor fibre of f. We prove that the orbifold E-functions of Berglund-Henningson dual pairs coincide up to a sign depending on the number of variables and a simple change of variables. The proof is based on a relation between monomials (say, elements of a monomial basis of the Milnor algebra of an invertible polynomial) and elements of the whole symmetry group of the dual polynomial.

  1. Dual-Modality, Dual-Functional Nanoprobes for Cellular and Molecular Imaging

    PubMed Central

    Menon, Jyothi U.; Gulaka, Praveen K.; McKay, Madalyn A.; Geethanath, Sairam; Liu, Li; Kodibagkar, Vikram D.

    2012-01-01

    An emerging need for evaluation of promising cellular therapies is a non-invasive method to image the movement and health of cells following transplantation. However, the use of a single modality to serve this purpose may not be advantageous as it may convey inaccurate or insufficient information. Multi-modal imaging strategies are becoming more popular for in vivo cellular and molecular imaging because of their improved sensitivity, higher resolution and structural/functional visualization. This study aims at formulating Nile Red doped hexamethyldisiloxane (HMDSO) nanoemulsions as dual modality (Magnetic Resonance Imaging/Fluorescence), dual-functional (oximetry/detection) nanoprobes for cellular and molecular imaging. HMDSO nanoprobes were prepared using a HS15-lecithin combination as surfactant and showed an average radius of 71±39 nm by dynamic light scattering and in vitro particle stability in human plasma over 24 hrs. They were found to readily localize in the cytosol of MCF7-GFP cells within 18 minutes of incubation. As proof of principle, these nanoprobes were successfully used for fluorescence imaging and for measuring pO2 changes in cells by magnetic resonance imaging, in vitro, thus showing potential for in vivo applications. PMID:23382776

  2. Dual ion beam deposition of carbon films with diamondlike properties

    NASA Technical Reports Server (NTRS)

    Mirtich, M. J.; Swec, D. M.; Angus, J. C.

    1984-01-01

    A single and dual ion beam system was used to generate amorphous carbon films with diamond like properties. A methane/argon mixture at a molar ratio of 0.28 was ionized in the low pressure discharge chamber of a 30-cm-diameter ion source. A second ion source, 8 cm in diameter was used to direct a beam of 600 eV Argon ions on the substrates (fused silica or silicon) while the deposition from the 30-cm ion source was taking place. Nuclear reaction and combustion analysis indicate H/C ratios for the films to be 1.00. This high value of H/C, it is felt, allowed the films to have good transmittance. The films were impervious to reagents which dissolve graphitic and polymeric carbon structures. Although the measured density of the films was approximately 1.8 gm/cu cm, a value lower than diamond, the films exhibited other properties that were relatively close to diamond. These films were compared with diamondlike films generated by sputtering a graphite target.

  3. Dual-Language Education for Low-Income Children: Preliminary Evidence of Benefits for Executive Function

    ERIC Educational Resources Information Center

    Esposito, Alena G.; Baker-Ward, Lynne

    2013-01-01

    This investigation is an initial examination of possible enhancement of executive function through a dual-language (50:50) education model. The ethnically diverse, low-income sample of 120 children from Grades K, 2, and 4 consisted of approximately equal numbers of children enrolled in dual-language and traditional classrooms. Dual-language…

  4. Dual-Functional Hydrazide-Reactive and Anhydride-Containing Oligomeric Hydrogel Building Blocks.

    PubMed

    Kascholke, Christian; Loth, Tina; Kohn-Polster, Caroline; Möller, Stephanie; Bellstedt, Peter; Schulz-Siegmund, Michaela; Schnabelrauch, Matthias; Hacker, Michael C

    2017-03-13

    Biomimetic hydrogels are advanced biomaterials that have been developed following different synthetic routes. Covalent postfabrication functionalization is a promising strategy to achieve efficient matrix modification decoupled of general material properties. To this end, dual-functional macromers were synthesized by free radical polymerization of maleic anhydride with diacetone acrylamide (N-(1,1-dimethyl-3-oxobutyl)acrylamide) and pentaerythritol diacrylate monostearate. Amphiphilic oligomers (M n < 7.5 kDa) with anhydride contents of 7-20% offered cross-linking reactivity to yield rigid hydrogels with gelatinous peptides (E = 4-13 kPa) and good cell adhesion properties. Mildly reactive methyl ketones as second functionality remained intact during hydrogel formation and potential of covalent matrix modification was shown using hydrazide and hydrazine model compounds. Successful secondary dihydrazide cross-linking was demonstrated by an increase of hydrogel stiffness (>40%). Efficient hydrazide/hydrazine immobilization depending on solution pH, hydrogel ketone content as well as ligand concentration for bioconjugation was shown and reversibility of hydrazone formation was indicated by physiologically relevant hydrazide release over 7 days. Proof-of-concept experiments with hydrazido-functionalized hyaluronan demonstrated potential for covalent aECM immobilization. The presented dual-functional macromers have perspective as reactive hydrogel building blocks for various biomedical applications.

  5. Dual number algebra method for Green's function derivatives in 3D magneto-electro-elasticity

    NASA Astrophysics Data System (ADS)

    Dziatkiewicz, Grzegorz

    2018-01-01

    The Green functions are the basic elements of the boundary element method. To obtain the boundary integral formulation the Green function and its derivative should be known for the considered differential operator. Today the interesting group of materials are electronic composites. The special case of the electronic composite is the magnetoelectroelastic continuum. The mentioned continuum is a model of the piezoelectric-piezomagnetic composites. The anisotropy of their physical properties makes the problem of Green's function determination very difficult. For that reason Green's functions for the magnetoelectroelastic continuum are not known in the closed form and numerical methods should be applied to determine such Green's functions. These means that the problem of the accurate and simply determination of Green's function derivatives is even harder. Therefore in the present work the dual number algebra method is applied to calculate numerically the derivatives of 3D Green's functions for the magnetoelectroelastic materials. The introduced method is independent on the step size and it can be treated as a special case of the automatic differentiation method. Therefore, the dual number algebra method can be applied as a tool for checking the accuracy of the well-known finite difference schemes.

  6. Scanning properties of large dual-shaped offset and symmetric reflector antennas

    NASA Astrophysics Data System (ADS)

    Galindo-Israel, Victor; Veruttipong, Watt; Norrod, Roger D.; Imbriale, William A.

    1992-04-01

    Several characteristics of dual offset (DOSR) and symmetric shaped reflectors are examined. Among these is the amelioration of the added cost of manufacturing a shaped reflector antenna, particularly a doubly curved surface for the DOSR, if adjustable panels, which may be necessary for correction of gravity and wind distortions, are also used for improving gain by shaping. The scanning properties of shaped reflectors, both offset and circularly symmetric, are examined and compared to conic section scanning characteristics. Scanning of the pencil beam is obtained by lateral and axial translation of a single point-source feed. The feed is kept pointed toward the center of the subreflector. The effects of power spillover and aperture phase error as a function of beam scanning is examined for several different types of large reflector designs including DOSR, circularly symmetric large f/D and smaller f/D dual reflector antenna systems. It is graphically illustrated that the Abbe-sine condition for improving scanning of an optical system cannot, inherently, be satisfied in a dual-shaped reflector system shaped for high gain and low feed spillover.

  7. Efficient sidelobe ASK based dual-function radar-communications

    NASA Astrophysics Data System (ADS)

    Hassanien, Aboulnasr; Amin, Moeness G.; Zhang, Yimin D.; Ahmad, Fauzia

    2016-05-01

    Recently, dual-function radar-communications (DFRC) has been proposed as means to mitigate the spectrum congestion problem. Existing amplitude-shift keying (ASK) methods for information embedding do not take full advantage of the highest permissable sidelobe level. In this paper, a new ASK-based signaling strategy for enhancing the signal-to-noise ratio (SNR) at the communication receiver is proposed. The proposed method employs one reference waveform and simultaneously transmits a number of orthogonal waveforms equals to the number of 1's in the binary sequence being embedded. 3 dB SNR gain is achieved using the proposed method as compared to existing sidelobe ASK methods. The effectiveness of the proposed information embedding strategy is verified using simulations examples.

  8. Characterizing individual differences in functional connectivity using dual-regression and seed-based approaches.

    PubMed

    Smith, David V; Utevsky, Amanda V; Bland, Amy R; Clement, Nathan; Clithero, John A; Harsch, Anne E W; McKell Carter, R; Huettel, Scott A

    2014-07-15

    A central challenge for neuroscience lies in relating inter-individual variability to the functional properties of specific brain regions. Yet, considerable variability exists in the connectivity patterns between different brain areas, potentially producing reliable group differences. Using sex differences as a motivating example, we examined two separate resting-state datasets comprising a total of 188 human participants. Both datasets were decomposed into resting-state networks (RSNs) using a probabilistic spatial independent component analysis (ICA). We estimated voxel-wise functional connectivity with these networks using a dual-regression analysis, which characterizes the participant-level spatiotemporal dynamics of each network while controlling for (via multiple regression) the influence of other networks and sources of variability. We found that males and females exhibit distinct patterns of connectivity with multiple RSNs, including both visual and auditory networks and the right frontal-parietal network. These results replicated across both datasets and were not explained by differences in head motion, data quality, brain volume, cortisol levels, or testosterone levels. Importantly, we also demonstrate that dual-regression functional connectivity is better at detecting inter-individual variability than traditional seed-based functional connectivity approaches. Our findings characterize robust-yet frequently ignored-neural differences between males and females, pointing to the necessity of controlling for sex in neuroscience studies of individual differences. Moreover, our results highlight the importance of employing network-based models to study variability in functional connectivity. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Characterizing Individual Differences in Functional Connectivity Using Dual-Regression and Seed-Based Approaches

    PubMed Central

    Smith, David V.; Utevsky, Amanda V.; Bland, Amy R.; Clement, Nathan; Clithero, John A.; Harsch, Anne E. W.; Carter, R. McKell; Huettel, Scott A.

    2014-01-01

    A central challenge for neuroscience lies in relating inter-individual variability to the functional properties of specific brain regions. Yet, considerable variability exists in the connectivity patterns between different brain areas, potentially producing reliable group differences. Using sex differences as a motivating example, we examined two separate resting-state datasets comprising a total of 188 human participants. Both datasets were decomposed into resting-state networks (RSNs) using a probabilistic spatial independent components analysis (ICA). We estimated voxelwise functional connectivity with these networks using a dual-regression analysis, which characterizes the participant-level spatiotemporal dynamics of each network while controlling for (via multiple regression) the influence of other networks and sources of variability. We found that males and females exhibit distinct patterns of connectivity with multiple RSNs, including both visual and auditory networks and the right frontal-parietal network. These results replicated across both datasets and were not explained by differences in head motion, data quality, brain volume, cortisol levels, or testosterone levels. Importantly, we also demonstrate that dual-regression functional connectivity is better at detecting inter-individual variability than traditional seed-based functional connectivity approaches. Our findings characterize robust—yet frequently ignored—neural differences between males and females, pointing to the necessity of controlling for sex in neuroscience studies of individual differences. Moreover, our results highlight the importance of employing network-based models to study variability in functional connectivity. PMID:24662574

  10. Mechanical Properties of a Superalloy Disk with a Dual Grain Structure

    NASA Technical Reports Server (NTRS)

    Gayda, John; Gabb, Timothy; Kantzos, Peter

    2003-01-01

    Mechanical properties from an advanced, nickel-base superalloy disk, with a dual grain structure consisting of a fine grain bore and coarse grain rim, were evaluated. The dual grain structure was produced using NASA's low cost Dual Microstructure Heat Treatment (DMHT) process. The results showed the DMHT disk to have a high strength, fatigue resistant bore comparable to a subsolvus (fine grain) heat treated disk, and a creep resistant rim comparable to a supersolvus (coarse grain) heat treated disk. Additional work on subsolvus solutioning before or after the DMHT conversion appears to be a viable avenue for further improvement in disk properties.

  11. Using Dual Regression to Investigate Network Shape and Amplitude in Functional Connectivity Analyses

    PubMed Central

    Nickerson, Lisa D.; Smith, Stephen M.; Öngür, Döst; Beckmann, Christian F.

    2017-01-01

    Independent Component Analysis (ICA) is one of the most popular techniques for the analysis of resting state FMRI data because it has several advantageous properties when compared with other techniques. Most notably, in contrast to a conventional seed-based correlation analysis, it is model-free and multivariate, thus switching the focus from evaluating the functional connectivity of single brain regions identified a priori to evaluating brain connectivity in terms of all brain resting state networks (RSNs) that simultaneously engage in oscillatory activity. Furthermore, typical seed-based analysis characterizes RSNs in terms of spatially distributed patterns of correlation (typically by means of simple Pearson's coefficients) and thereby confounds together amplitude information of oscillatory activity and noise. ICA and other regression techniques, on the other hand, retain magnitude information and therefore can be sensitive to both changes in the spatially distributed nature of correlations (differences in the spatial pattern or “shape”) as well as the amplitude of the network activity. Furthermore, motion can mimic amplitude effects so it is crucial to use a technique that retains such information to ensure that connectivity differences are accurately localized. In this work, we investigate the dual regression approach that is frequently applied with group ICA to assess group differences in resting state functional connectivity of brain networks. We show how ignoring amplitude effects and how excessive motion corrupts connectivity maps and results in spurious connectivity differences. We also show how to implement the dual regression to retain amplitude information and how to use dual regression outputs to identify potential motion effects. Two key findings are that using a technique that retains magnitude information, e.g., dual regression, and using strict motion criteria are crucial for controlling both network amplitude and motion-related amplitude

  12. On dual and three space problems for the compact approximation property

    NASA Astrophysics Data System (ADS)

    Choi, Changsun; Kim, Ju Myung

    2006-11-01

    We introduce the properties W*D and BW*D for the dual space of a Banach space. And then solve the dual problem for the compact approximation property (CAP): if X* has the CAP and the W*D, then X has the CAP. Also, we solve the three space problem for the CAP: for example, if M is a closed subspace of a Banach space such that M[perpendicular] is complemented in X* and X* has the W*D, then X has the CAP whenever X/M has the CAP and M has the bounded CAP. Corresponding problems for the bounded compact approximation property are also addressed.

  13. Combinatorial atmospheric pressure chemical vapor deposition of graded TiO₂-VO₂ mixed-phase composites and their dual functional property as self-cleaning and photochromic window coatings.

    PubMed

    Wilkinson, Mia; Kafizas, Andreas; Bawaked, Salem M; Obaid, Abdullah Y; Al-Thabaiti, Shaeel A; Basahel, Sulaiman N; Carmalt, Claire J; Parkin, Ivan P

    2013-06-10

    A combinatorial film with a phase gradient from V:TiO₂ (V: Ti ≥ 0.08), through a range of TiO₂-VO₂ composites, to a vanadium-rich composite (V: Ti = 1.81) was grown by combinatorial atmospheric pressure chemical vapor deposition (cAPCVD). The film was grown from the reaction of TiCl₄, VCl₄, ethyl acetate (EtAc), and H₂O at 550 °C on glass. The gradient in gas mixtures across the reactor induced compositional film growth, producing a single film with numerous phases and compositions at different positions. Seventeen unique positions distributed evenly along a central horizontal strip were investigated. The physical properties were characterized by wavelength dispersive X-ray (WDX) analysis, X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and UV-visible spectroscopy. The functional properties examined included the degree of photoinduced hydrophilicity (PIH), UVC-photocatalysis, and thermochromism. Superhydrophilic contact angles could be achieved at all positions, even within a highly VO₂-rich composite (V: Ti = 1.81). A maximum level of UVC photocatalysis was observed at a position bordering the solubility limit of V:TiO₂ (V: Ti ≈ 0.21) and fragmentation into a mixed-phase composite. Within the mixed-phase TiO₂: VO₂ composition region (V: Ti = 1.09 to 1.81) a decrease in the semiconductor-to-metal transition temperature of VO₂ from 68 to 51 °C was observed.

  14. Dual Function of Phosphoubiquitin in E3 Activation of Parkin*

    PubMed Central

    Walinda, Erik; Morimoto, Daichi; Sugase, Kenji; Shirakawa, Masahiro

    2016-01-01

    Mutations in the gene encoding parkin, an auto-inhibited E3 ubiquitin ligase that functions in the clearance of damaged mitochondria, are the most common cause of autosomal recessive juvenile Parkinsonism. The mechanism regulating parkin activation remains poorly understood. Here we show, by using isothermal titration calorimetry, solution NMR, and fluorescence spectroscopy, that parkin can bind ubiquitin and phosphomimetic ubiquitin by recognizing the canonical hydrophobic patch and C terminus of ubiquitin. The affinity of parkin for both phosphomimetic and unmodified ubiquitin is markedly enhanced upon removal of the ubiquitin-like (UBL) domain of parkin. This suggests that the agonistic binding of ubiquitin to parkin in trans is counterbalanced by the antagonistic activity of the parkin UBL domain in cis. Intriguingly, UBL binding is enthalpy-driven, whereas ubiquitin binding is driven by an increase in the total entropy of the system. These thermodynamic differences are explained by different chemistry in the ubiquitin- and UBL-binding pockets of parkin and, as shown by molecular dynamics simulations, are not a consequence of changes in protein conformational entropy. Indeed, comparison of conformational fluctuations reveals that the RING1-IBR element becomes considerably more rigid upon complex formation. A model of parkin activation is proposed in which E2∼Ub binding triggers large scale diffusional motion of the RING2 domain toward the ubiquitin-stabilized RING1-IBR assembly to complete formation of the active parkin-E2∼Ub transfer complex. Thus, ubiquitin plays a dual role in parkin activation by competing with the inhibitory UBL domain and stabilizing the active form of parkin. PMID:27284007

  15. Dual Function of Phosphoubiquitin in E3 Activation of Parkin.

    PubMed

    Walinda, Erik; Morimoto, Daichi; Sugase, Kenji; Shirakawa, Masahiro

    2016-08-05

    Mutations in the gene encoding parkin, an auto-inhibited E3 ubiquitin ligase that functions in the clearance of damaged mitochondria, are the most common cause of autosomal recessive juvenile Parkinsonism. The mechanism regulating parkin activation remains poorly understood. Here we show, by using isothermal titration calorimetry, solution NMR, and fluorescence spectroscopy, that parkin can bind ubiquitin and phosphomimetic ubiquitin by recognizing the canonical hydrophobic patch and C terminus of ubiquitin. The affinity of parkin for both phosphomimetic and unmodified ubiquitin is markedly enhanced upon removal of the ubiquitin-like (UBL) domain of parkin. This suggests that the agonistic binding of ubiquitin to parkin in trans is counterbalanced by the antagonistic activity of the parkin UBL domain in cis Intriguingly, UBL binding is enthalpy-driven, whereas ubiquitin binding is driven by an increase in the total entropy of the system. These thermodynamic differences are explained by different chemistry in the ubiquitin- and UBL-binding pockets of parkin and, as shown by molecular dynamics simulations, are not a consequence of changes in protein conformational entropy. Indeed, comparison of conformational fluctuations reveals that the RING1-IBR element becomes considerably more rigid upon complex formation. A model of parkin activation is proposed in which E2∼Ub binding triggers large scale diffusional motion of the RING2 domain toward the ubiquitin-stabilized RING1-IBR assembly to complete formation of the active parkin-E2∼Ub transfer complex. Thus, ubiquitin plays a dual role in parkin activation by competing with the inhibitory UBL domain and stabilizing the active form of parkin. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Establishing Dual Electrogenerated Chemiluminescence and Multi-Color Electrochromism in Functional Ionic Transition Metal Complexes

    SciTech Connect

    Puodziukynaite, Egle; Oberst, Justin L.; Dyer, Aubrey L.

    A combination of electrochromism and electroluminescence in functional materials could lead to single-layer dual electrochromic/electroluminescent (EC/EL) display devices, capable of simultaneous operation in emissive and reflective modes. Whereas such next generation displays could provide optimal visibility in any ambient lighting situation, materials available that exhibit such characteristics in the active layer are limited due to the required intrinsic multifunctionality (i.e., redox activity, electroluminescence, electrochromism, and ion conductivity) and to date can only be achieved via the rational design of ionic transition-metal complexes. Reported herein is the synthesis and characterization of a new family of acrylate-containing ruthenium (tris)bipyridine-based coordination complexes withmore » multifunctional characteristics. Potential use of the presented compounds in EC/EL devices is established, as they are applied as cross-linked electrochromic films and electrochemiluminescent layers in light-emitting electrochemical cell devices. Electrochromic switching of the polymeric networks between yellow, orange, green, brown and transmissive states is demonstrated, and electrochemiluminescent devices based on the complexes synthesized show red-orange to deep red emission with λ{sub max} ranging from 680 to 722 nm and luminance up to 135 cd/m{sup 2}. Additionally, a dual EC/EL device prototype is presented where light emission and multicolor electrochromism occur from the same pixel comprised of a single active layer, demonstrating a true combination of these properties in ionic transition-metal complexes.« less

  17. Establishing Dual Electrogenerated Chemiluminescence and Multicolor Electrochromism in Functional Ionic Transition-Metal Complexes

    SciTech Connect

    Puodziukynaite, Egle; Oberst, Justin L.; Dyer, Aubrey L.

    A combination of electrochromism and electroluminescence in functional materials could lead to single-layer dual electrochromic/electroluminescent (EC/EL) display devices, capable of simultaneous operation in emissive and reflective modes. Whereas such next generation displays could provide optimal visibility in any ambient lighting situation, materials available that exhibit such characteristics in the active layer are limited due to the required intrinsic multifunctionality (i.e., redox activity, electroluminescence, electrochromism, and ion conductivity) and to date can only be achieved via the rational design of ionic transition-metal complexes. Reported herein is the synthesis and characterization of a new family of acrylate-containing ruthenium (tris)bipyridine-based coordination complexes withmore » multifunctional characteristics. Potential use of the presented compounds in EC/EL devices is established, as they are applied as cross-linked electrochromic films and electrochemiluminescent layers in light-emitting electrochemical cell devices. Electrochromic switching of the polymeric networks between yellow, orange, green, brown and transmissive states is demonstrated, and electrochemiluminescent devices based on the complexes synthesized show red-orange to deep red emission with λmax ranging from 680 to 722 nm and luminance up to 135 cd/m². Additionally, a dual EC/EL device prototype is presented where light emission and multicolor electrochromism occur from the same pixel comprised of a single active layer, demonstrating a true combination of these properties in ionic transition-metal complexes.« less

  18. High-Quality Reduced Graphene Oxide by a Dual-Function Chemical Reduction and Healing Process

    PubMed Central

    Some, Surajit; Kim, Youngmin; Yoon, Yeoheung; Yoo, HeeJoun; Lee, Saemi; Park, Younghun; Lee, Hyoyoung

    2013-01-01

    A new chemical dual-functional reducing agent, thiophene, was used to produce high-quality reduced graphene oxide (rGO) as a result of a chemical reduction of graphene oxide (GO) and the healing of rGO. Thiophene reduced GO by donation of electrons with acceptance of oxygen while it was converted into an intermediate oxidised polymerised thiophene that was eventually transformed into polyhydrocarbon by loss of sulphur atoms. Surprisingly, the polyhydrocarbon template helped to produce good-quality rGOC (chemically reduced) and high-quality rGOCT after thermal treatment. The resulting rGOCT nanosheets did not contain any nitrogen or sulphur impurities, were highly deoxygenated and showed a healing effect. Thus the electrical properties of the as-prepared rGOCT were superior to those of conventional hydrazine-produced rGO that require harsh reaction conditions. Our novel dual reduction and healing method with thiophene could potentially save energy and facilitate the commercial mass production of high-quality graphene. PMID:23722643

  19. Processing, Microstructures and Properties of a Dual Phase Precipitation-Hardening PM Stainless Steel

    NASA Astrophysics Data System (ADS)

    Schade, Christopher

    To improve the mechanical properties of PM stainless steels in comparison with their wrought counterparts, a PM stainless steel alloy was developed which combines a dual-phase microstructure with precipitation-hardening. The use of a mixed microstructure of martensite and ferrite results in an alloy with a combination of the optimum properties of each phase, namely strength and ductility. The use of precipitation hardening via the addition of copper results in additional strength and hardness. A range of compositions was studied in combination with various sintering conditions to determine the optimal thermal processing to achieve the desired microstructure. The microstructure could be varied from predominately ferrite to one containing a high percentage of martensite by additions of copper and a variation of the sintering temperature before rapid cooling. Mechanical properties (transverse rupture strength (TRS), yield strength, tensile strength, ductility and impact toughness) were measured as a function of the v/o ferrite in the microstructure. A dual phase alloy with the optimal combination of properties served as the base for introducing precipitation hardening. Copper was added to the base alloy at various levels and its effect on the microstructure and mechanical properties was quantified. Processing at various sintering temperatures led to a range of microstructures; dilatometry was used utilized to monitor and understand the transformations and the formation of the two phases. The aging process was studied as a function of temperature and time by measuring TRS, yield strength, tensile strength, ductility, impact toughness and apparent hardness. It was determined that optimum aging was achieved at 538°C for 1h. Aging at slightly lower temperatures led to the formation of carbides, which contributed to reduced hardness and tensile strength. As expected, at the peak aging temperature, an increase in yield strength and ultimate tensile strength as well as

  20. High-efficiency dual-modes vortex beam generator with polarization-dependent transmission and reflection properties.

    PubMed

    Tang, Shiwei; Cai, Tong; Wang, Guang-Ming; Liang, Jian-Gang; Li, Xike; Yu, Jiancheng

    2018-04-23

    Vortex beam is believed to be an effective way to extend communication capacity, but available efforts suffer from the issues of complex configurations, fixed operation mode as well as low efficiency. Here, we propose a general strategy to design dual-modes vortex beam generator by using metasurfaces with polarization-dependent transmission and reflection properties. Combining the focusing and vortex functionalities, we design/fabricate a type of compact dual-modes vortex beam generator operating at both reflection/transmission sides of the system. Experimental results demonstrate that the designed metadevice can switch freely and independently between the reflective vortex with topological charge m 1  = 2 and transmissive vortex with m 2  = 1. Moreover, the metadevice exhibits very high efficiencies of 91% and 85% for the reflective and transmissive case respectively. Our findings open a door for multifunctional metadevices with high performances, which indicate wide applications in modern integration-optics and wireless communication systems.

  1. Certain topological properties and duals of the domain of a triangle matrix in a sequence space

    NASA Astrophysics Data System (ADS)

    Altay, Bilâl; Basar, Feyzi

    2007-12-01

    The matrix domain of the particular limitation methods Cesàro, Riesz, difference, summation and Euler were studied by several authors. In the present paper, certain topological properties and [beta]- and [gamma]-duals of the domain of a triangle matrix in a sequence space have been examined as an application of the characterization of the related matrix classes.

  2. Enzyme-guided plasmonic biosensor based on dual-functional nanohybrid for sensitive detection of thrombin.

    PubMed

    Yan, Jing; Wang, Lida; Tang, Longhua; Lin, Lei; Liu, Yang; Li, Jinghong

    2015-08-15

    Rapid and sensitive methodologies for the detection of protein are in urgent requirement for clinic diagnostics. Localized surface plasmon resonance (LSPR) of metal nanostructures has the potential to circumvent this problem due to its sensitive optical properties and strong electromagnetic near-field enhancements. In this work, an enzyme mediated plasmonic biosensor on the basis of a dual-functional nanohybrid was developed for the detection of thrombin. By utilizing LSPR-responsive nanohybrid and anaptamer-enzyme conjugated reporting probe, the sensing platform brings enhanced signal, stability as well as simplicity. Enzymatic reaction catalyzed the reduction of Au(3+) to Au° in situ, further leading to the rapid crystal growth of gold nanoparticles (AuNPs). The LSPR absorbance band and color changed company with the nanoparticle generation, which can be real-time monitoring by UV-visible spectrophotometer and naked eye. Nanohybrid constructed by gold and magnetic nanoparticles acts as a dual functional plasmonic unit, which not only plays the role of signal production, but also endows the sensor with the function of magnetic separation. Simultaneously, the introduction of enzyme effectively regulates the programming crystal growth of AuNPs. In addition, enzyme also serves as signal amplifier owing to its high catalysis efficiency. The response of the plasmonic sensor varies linearly with the logarithmic thrombin concentration up to 10nM with a limit of detection of 200 pM. The as-proposed strategy shows good analytical performance for thrombin determination. This simple, disposable method is promising in developing universal platforms for protein monitoring, drug discovery and point-of-care diagnostics. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. The Role of Control Functions in Mentalizing: Dual-Task Studies of Theory of Mind and Executive Function

    ERIC Educational Resources Information Center

    Bull, Rebecca; Phillips, Louise H.; Conway, Claire A.

    2008-01-01

    Conflicting evidence has arisen from correlational studies regarding the role of executive control functions in Theory of Mind. The current study used dual-task manipulations of executive functions (inhibition, updating and switching) to investigate the role of these control functions in mental state and non-mental state tasks. The "Eyes"…

  4. Associations between physical function, dual-task performance and cognition in patients with mild Alzheimer's disease.

    PubMed

    Sobol, Nanna Aue; Hoffmann, Kristine; Vogel, Asmus; Lolk, Annette; Gottrup, Hanne; Høgh, Peter; Hasselbalch, Steen G; Beyer, Nina

    2016-11-01

    Alzheimer's disease (AD) causes a gradual decline in cognition, limitations of dual-tasking and physical function leading to total dependence. Hence, information about the interaction between physical function, dual-task performance and cognition may lead to new treatment strategies with the purpose of preserving function and quality of life. The objective of this study was to investigate the associations between physical function, dual-task performance and cognition in community-dwelling patients with mild AD. Baseline results from 185 participants (50-90 years old) in the single blinded multicenter RCT 'ADEX' (Alzheimer's disease: the effect of physical exercise) were used. Assessments included tests of physical function: 400-m walk test, 10-m walk test, Timed Up and Go test and 30-s chair stand test; dual-task performance, i.e., 10-m walk while counting backwards from 50 or naming the months backwards; and cognition, i.e., Mini Mental State Examination, Symbol Digit Modalities Test, the Stroop Color and Word Test, and Lexical verbal fluency test. Results in the 30-s chair stand test correlated significantly with all tests of cognition (r = .208-.242) while the other physical function tests only randomly correlated with tests of cognition. Results in the dual-task counting backwards correlated significantly with results in all tests of cognition (r = .259-.388), which accounted for 7%-15% of the variation indicating that a faster time to complete dual-task performance was associated with better cognitive performance. The evidence of the associations between physical function, dual-task performance and cognition is important when creating new rehabilitation interventions to patients with mild AD.

  5. Dual Use of Bladder Anticholinergics and Cholinesterase Inhibitors: Long-Term Functional and Cognitive Outcomes

    PubMed Central

    Sink, Kaycee M.; Thomas, Joseph; Xu, Huiping; Craig, Bruce; Kritchevsky, Steven; Sands, Laura P.

    2015-01-01

    OBJECTIVES To determine the cognitive and functional consequences of dual use of cholinesterase inhibitors (ChIs) and the bladder anticholinergics oxybutynin or tolterodine. DESIGN Prospective cohort study. SETTING Nursing homes (NHs) in the state of Indiana. PARTICIPANTS Three thousand five hundred thirty-six Medicaid-eligible NH residents aged 65 and older taking a ChI between January 1, 2003, and December 31, 2004. Residents were excluded if they were taking an anticholinergic other than oxybutynin or tolterodine. MEASUREMENTS Indiana Medicaid claims data were merged with data from the Minimum Data Set (MDS). Repeated-measures analyses were performed to assess the effects of dual therapy on change in cognitive function measured using the MDS Cognition Scale (MDS-COGS; scored 0–10) and change in activity of daily living (ADL) function using the seven ADL items in the MDS (scored 0–28). Potential covariates included age, sex, race, number of medications, and Charlson Comorbidity Index score. RESULTS Three hundred seventy-six (10.6%) residents were prescribed oxybutynin or tolterodine concomitantly with a ChI. In residents in the top quartile of ADL function, ADL function declined an average of 1.08 points per quarter when not taking bladder anticholinergics (ChI alone), compared with 1.62 points per quarter when taking dual therapy, a 50% greater rate in quarterly decline in ADL function (P =.01). There was no excess decline attributable to dual therapy in MDS-COGS scores or in ADL function for residents who started out with lower functioning. CONCLUSION In higher-functioning NH residents, dual use of ChIs and bladder anticholinergics may result in greater rates of functional decline than use of ChIs alone. The MDS-COGS may not be sensitive enough to detect differences in cognition due to dual use. PMID:18384584

  6. Dual functional nisin-multi-walled carbon nanotubes coated filters for bacterial capture and inactivation.

    PubMed

    Dong, Xiuli; Yang, Liju

    2015-01-01

    Removal of pathogens from water is one way to prevent waterborne illness. In this paper, we developed dual functional carbon nanotube (CNT) modified filters for bacterial capture and inactivation, utilizing multi-walled CNTs (MWCNTs) to coat on commercially available filters and making use of the exceptional adsorption property of CNTs to adsorb a natural antimicrobial peptide-nisin on it. Two types of MWCNTs with different outer layer diameters were used (MWCNTs1: <8 nm in diameter; MWCNTs2: 10-20 nm in diameter). The thickness of MWCNT layers, surface morphology, and surface hydrophobicity of both types of MWCNT coated filters were characterized. The MWCNT coating on filters significantly increased the surface hydrophobicity. The absorption of nisin and the capture of bacterial pathogens were correlated with increased surface hydrophobicity. The MWCNTs1 and MWCNTs2 filters with 1.5 mg MWCNTs loading captured 2.44 and 3.88 log of cells, respectively, from aqueous solutions containing a total of ~10(6) CFU/mL cells. Nisin deposit at the amount of 0.5 mg on the surfaces of MWCNT filters significantly reduced the viability of captured B. anthracis cells by 95.71-97.19 %, and inhibited the metabolic activities of the captured cells by approximately 98.3 %. The results demonstrated that the MWCNT-nisin filters achieved dual functions in bacterial pathogen capture and inhibition in one single filtration step, which is potentially applicable in removing undesired microorganisms from water sources and inhibiting captured Gram positive bacteria activities.

  7. Polynomial dual energy inverse functions for bone Calcium/Phosphorus ratio determination and experimental evaluation.

    PubMed

    Sotiropoulou, P; Fountos, G; Martini, N; Koukou, V; Michail, C; Kandarakis, I; Nikiforidis, G

    2016-12-01

    An X-ray dual energy (XRDE) method was examined, using polynomial nonlinear approximation of inverse functions for the determination of the bone Calcium-to-Phosphorus (Ca/P) mass ratio. Inverse fitting functions with the least-squares estimation were used, to determine calcium and phosphate thicknesses. The method was verified by measuring test bone phantoms with a dedicated dual energy system and compared with previously published dual energy data. The accuracy in the determination of the calcium and phosphate thicknesses improved with the polynomial nonlinear inverse function method, introduced in this work, (ranged from 1.4% to 6.2%), compared to the corresponding linear inverse function method (ranged from 1.4% to 19.5%). Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Advanced age dissociates dual functions of the perirhinal cortex.

    PubMed

    Burke, Sara N; Maurer, Andrew P; Nematollahi, Saman; Uprety, Ajay; Wallace, Jenelle L; Barnes, Carol A

    2014-01-08

    The perirhinal cortex (PRC) is proposed to both represent high-order sensory information and maintain those representations across delays. These cognitive processes are required for recognition memory, which declines during normal aging. Whether or not advanced age affects the ability of PRC principal cells to support these dual roles, however, is not known. The current experiment recorded PRC neurons as young and aged rats traversed a track. When objects were placed on the track, a subset of the neurons became active at discrete locations adjacent to objects. Importantly, the aged rats had a lower proportion of neurons that were activated by objects. Once PRC activity patterns in the presence of objects were established, however, both age groups maintained these representations across delays up to 2 h. These data support the hypothesis that age-associated deficits in stimulus recognition arise from impairments in high-order stimulus representation rather than difficulty in sustaining stable activity patterns over time.

  9. Advanced Age Dissociates Dual Functions of the Perirhinal Cortex

    PubMed Central

    Burke, Sara N.; Maurer, Andrew P.; Nematollahi, Saman; Uprety, Ajay; Wallace, Jenelle L.

    2014-01-01

    The perirhinal cortex (PRC) is proposed to both represent high-order sensory information and maintain those representations across delays. These cognitive processes are required for recognition memory, which declines during normal aging. Whether or not advanced age affects the ability of PRC principal cells to support these dual roles, however, is not known. The current experiment recorded PRC neurons as young and aged rats traversed a track. When objects were placed on the track, a subset of the neurons became active at discrete locations adjacent to objects. Importantly, the aged rats had a lower proportion of neurons that were activated by objects. Once PRC activity patterns in the presence of objects were established, however, both age groups maintained these representations across delays up to 2 h. These data support the hypothesis that age-associated deficits in stimulus recognition arise from impairments in high-order stimulus representation rather than difficulty in sustaining stable activity patterns over time. PMID:24403147

  10. Structures of parasite calreticulins provide insights into their flexibility and dual carbohydrate/peptide-binding properties.

    PubMed

    Moreau, Christophe; Cioci, Gianluca; Iannello, Marina; Laffly, Emmanuelle; Chouquet, Anne; Ferreira, Arturo; Thielens, Nicole M; Gaboriaud, Christine

    2016-11-01

    Calreticulin (CRT) is a multifaceted protein, initially discovered as an endoplasmic reticulum (ER) chaperone protein, that is essential in calcium metabolism. Various implications in cancer, early development and immunology have been discovered more recently for CRT, as well as its role as a dominant 'eat-me' prophagocytic signal. Intriguingly, cell-surface exposure/secretion of CRT is among the infective strategies used by parasites such as Trypanosoma cruzi , Entamoeba histolytica , Taenia solium , Leishmania donovani and Schistosoma mansoni . Because of the inherent flexibility of CRTs, their analysis by X-ray crystallography requires the design of recombinant constructs suitable for crystallization, and thus only the structures of two very similar mammalian CRT lectin domains are known. With the X-ray structures of two distant parasite CRTs, insights into species structural determinants that might be harnessed to fight against the parasites without affecting the functions of the host CRT are now provided. Moreover, although the hypothesis that CRT can exhibit both open and closed conformations has been proposed in relation to its chaperone function, only the open conformation has so far been observed in crystal structures. The first evidence is now provided of a complex conformational transition with the junction reoriented towards P-domain closure. SAXS experiments also provided additional information about the flexibility of T. cruzi CRT in solution, thus complementing crystallographic data on the open conformation. Finally, regarding the conserved lectin-domain structure and chaperone function, evidence is provided of its dual carbohydrate/protein specificity and a new scheme is proposed to interpret such unusual substrate-binding properties. These fascinating features are fully consistent with previous experimental observations, as discussed considering the broad spectrum of CRT sequence conservations and differences.

  11. Properties of resonance wave functions.

    NASA Technical Reports Server (NTRS)

    More, R. M.; Gerjuoy, E.

    1973-01-01

    Construction and study of resonance wave functions corresponding to poles of the Green's function for several illustrative models of theoretical interest. Resonance wave functions obtained from the Siegert and Kapur-Peierls definitions of the resonance energies are compared. The comparison especially clarifies the meaning of the normalization constant of the resonance wave functions. It is shown that the wave functions may be considered renormalized in a sense analogous to that of quantum field theory. However, this renormalization is entirely automatic, and the theory has neither ad hoc procedures nor infinite quantities.

  12. Surface enhanced Raman scattering activity of dual-functional Fe3O4/Au composites

    NASA Astrophysics Data System (ADS)

    Wang, Li-Ping; Huang, Yu-Bin; Lai, Ying-Huang

    2018-03-01

    There is a high demand for multifunctional materials that can integrate sample collection and sensing. In this study, magnetic Fe3O4 clusters were fabricated using a simple solvent-thermal method. The effect of the reductant (sodium citrate, SC) on the structure and morphology of Fe3O4 was examined by the variation in the reagent amount. The resulting Fe3O4 clusters were functionalized with 3-aminopropyltriethoxysilane (APTES) to anchor Au nanoparticles to its surface. The fabricated composites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and a superconducting quantum interference device (SQUID) magnetometer. Dual-functional Fe3O4/Au clusters were obtained, effectively combining magnetic and plasmonic optical properties. The magnetic Fe3O4 cluster cores permitted the adsorption of the probe molecules, while sample concentration and collection were carried out under an external magnetic field. In addition, 4-nitrothiophenol (4-NTP) was chosen as the probe molecule to examine the analyte concentration ability and surface-enhanced Raman scattering (SERS) activity of the Fe3O4/Au composites. The results indicated that the Fe3O4/Au clusters exhibit a prominent SERS effect. The best 4-NTP detection limit obtained was 1 × 10-8 M, with a corresponding SERS analytical enhancement factor (AEF) exceeding 2 × 105.

  13. Error analysis and new dual-cosine window for estimating the sensor frequency response function from the step response data

    NASA Astrophysics Data System (ADS)

    Yang, Shuang-Long; Liang, Li-Ping; Liu, Hou-De; Xu, Ke-Jun

    2018-03-01

    Aiming at reducing the estimation error of the sensor frequency response function (FRF) estimated by the commonly used window-based spectral estimation method, the error models of interpolation and transient errors are derived in the form of non-parameter models. Accordingly, window effects on the errors are analyzed and reveal that the commonly used hanning window leads to smaller interpolation error which can also be significantly eliminated by the cubic spline interpolation method when estimating the FRF from the step response data, and window with smaller front-end value can restrain more transient error. Thus, a new dual-cosine window with its non-zero discrete Fourier transform bins at -3, -1, 0, 1, and 3 is constructed for FRF estimation. Compared with the hanning window, the new dual-cosine window has the equivalent interpolation error suppression capability and better transient error suppression capability when estimating the FRF from the step response; specifically, it reduces the asymptotic property of the transient error from O(N-2) of the hanning window method to O(N-4) while only increases the uncertainty slightly (about 0.4 dB). Then, one direction of a wind tunnel strain gauge balance which is a high order, small damping, and non-minimum phase system is employed as the example for verifying the new dual-cosine window-based spectral estimation method. The model simulation result shows that the new dual-cosine window method is better than the hanning window method for FRF estimation, and compared with the Gans method and LPM method, it has the advantages of simple computation, less time consumption, and short data requirement; the actual data calculation result of the balance FRF is consistent to the simulation result. Thus, the new dual-cosine window is effective and practical for FRF estimation.

  14. Retrieval of Snow Properties for Ku- and Ka-band Dual-Frequency Radar

    NASA Technical Reports Server (NTRS)

    Liao, Liang; Meneghini, Robert; Tokay, Ali; Bliven, Larry F.

    2016-01-01

    The focus of this study is on the estimation of snow microphysical properties and the associated bulk parameters such as snow water content and water equivalent snowfall rate for Ku- and Ka-band dual-frequency radar. This is done by exploring a suitable scattering model and the proper particle size distribution (PSD) assumption that accurately represent, in the electromagnetic domain, the micro/macro-physical properties of snow. The scattering databases computed from simulated aggregates for small-to-moderate particle sizes are combined with a simple scattering model for large particle sizes to characterize snow scattering properties over the full range of particle sizes. With use of the single-scattering results, the snow retrieval lookup tables can be formed in a way that directly links the Ku- and Ka-band radar reflectivities to snow water content and equivalent snowfall rate without use of the derived PSD parameters. A sensitivity study of the retrieval results to the PSD and scattering models is performed to better understand the dual-wavelength retrieval uncertainties. To aid in the development of the Ku- and Ka-band dual-wavelength radar technique and to further evaluate its performance, self-consistency tests are conducted using measurements of the snow PSD and fall velocity acquired from the Snow Video Imager Particle Image Probe (SVIPIP) duringthe winter of 2014 at the NASA Wallops Flight Facility site in Wallops Island, Virginia.

  15. Retrieval of Snow Properties for Ku- and Ka-Band Dual-Frequency Radar

    NASA Technical Reports Server (NTRS)

    Liao, Liang; Meneghini, Robert; Tokay, Ali; Bliven, Larry F.

    2016-01-01

    The focus of this study is on the estimation of snow microphysical properties and the associated bulk parameters such as snow water content and water equivalent snowfall rate for Ku- and Ka-band dual-frequency radar. This is done by exploring a suitable scattering model and the proper particle size distribution (PSD) assumption that accurately represent, in the electromagnetic domain, the micro-macrophysical properties of snow. The scattering databases computed from simulated aggregates for small-to-moderate particle sizes are combined with a simple scattering model for large particle sizes to characterize snow-scattering properties over the full range of particle sizes. With use of the single-scattering results, the snow retrieval lookup tables can be formed in a way that directly links the Ku- and Ka-band radar reflectivities to snow water content and equivalent snowfall rate without use of the derived PSD parameters. A sensitivity study of the retrieval results to the PSD and scattering models is performed to better understand the dual-wavelength retrieval uncertainties. To aid in the development of the Ku- and Ka-band dual-wavelength radar technique and to further evaluate its performance, self-consistency tests are conducted using measurements of the snow PSD and fall velocity acquired from the Snow Video Imager Particle Image Probe (SVIPIP) during the winter of 2014 at the NASA Wallops Flight Facility site in Wallops Island, Virginia.

  16. Thio-urethanes improve properties of dual-cured composite cements.

    PubMed

    Bacchi, A; Dobson, A; Ferracane, J L; Consani, R; Pfeifer, C S

    2014-12-01

    This study aims at modifying dual-cure composite cements by adding thio-urethane oligomers to improve mechanical properties, especially fracture toughness, and reduce polymerization stress. Thiol-functionalized oligomers were synthesized by combining 1,3-bis(1-isocyanato-1-methylethyl)benzene with trimethylol-tris-3-mercaptopropionate, at 1:2 isocyanate:thiol. Oligomer was added at 0, 10 or 20 wt% to BisGMA-UDMA-TEGDMA (5:3:2, with 25 wt% silanated inorganic fillers) or to one commercial composite cement (Relyx Ultimate, 3M Espe). Near-IR was used to measure methacrylate conversion after photoactivation (700 mW/cm(2) × 60s) and after 72 h. Flexural strength and modulus, toughness, and fracture toughness were evaluated in three-point bending. Polymerization stress was measured with the Bioman. The microtensile bond strength of an indirect composite and a glass ceramic to dentin was also evaluated. Results were analyzed with analysis of variance and Tukey's test (α = 0.05). For BisGMA-UDMA-TEGDMA cements, conversion values were not affected by the addition of thio-urethanes. Flexural strength/modulus increased significantly for both oligomer concentrations, with a 3-fold increase in toughness at 20 wt%. Fracture toughness increased over 2-fold for the thio-urethane modified groups. Contraction stress was reduced by 40% to 50% with the addition of thio-urethanes. The addition of thio-urethane to the commercial cement led to similar flexural strength, toughness, and conversion at 72h compared to the control. Flexural modulus decreased for the 20 wt% group, due to the dilution of the overall filler volume, which also led to decreased stress. However, fracture toughness increased by up to 50%. The microtensile bond strength increased for the experimental composite cement with 20 wt% thio-urethane bonding for both an indirect composite and a glass ceramic. Novel dual-cured composite cements containing thio-urethanes showed increased toughness, fracture toughness and

  17. Thio-urethanes Improve Properties of Dual-cured Composite Cements

    PubMed Central

    Bacchi, A.; Dobson, A.; Ferracane, J.L.; Consani, R.; Pfeifer, C.S.

    2014-01-01

    This study aims at modifying dual-cure composite cements by adding thio-urethane oligomers to improve mechanical properties, especially fracture toughness, and reduce polymerization stress. Thiol-functionalized oligomers were synthesized by combining 1,3-bis(1-isocyanato-1-methylethyl)benzene with trimethylol-tris-3-mercaptopropionate, at 1:2 isocyanate:thiol. Oligomer was added at 0, 10 or 20 wt% to BisGMA-UDMA-TEGDMA (5:3:2, with 25 wt% silanated inorganic fillers) or to one commercial composite cement (Relyx Ultimate, 3M Espe). Near-IR was used to measure methacrylate conversion after photoactivation (700 mW/cm2 × 60s) and after 72 h. Flexural strength and modulus, toughness, and fracture toughness were evaluated in three-point bending. Polymerization stress was measured with the Bioman. The microtensile bond strength of an indirect composite and a glass ceramic to dentin was also evaluated. Results were analyzed with analysis of variance and Tukey’s test (α = 0.05). For BisGMA-UDMA-TEGDMA cements, conversion values were not affected by the addition of thio-urethanes. Flexural strength/modulus increased significantly for both oligomer concentrations, with a 3-fold increase in toughness at 20 wt%. Fracture toughness increased over 2-fold for the thio-urethane modified groups. Contraction stress was reduced by 40% to 50% with the addition of thio-urethanes. The addition of thio-urethane to the commercial cement led to similar flexural strength, toughness, and conversion at 72h compared to the control. Flexural modulus decreased for the 20 wt% group, due to the dilution of the overall filler volume, which also led to decreased stress. However, fracture toughness increased by up to 50%. The microtensile bond strength increased for the experimental composite cement with 20 wt% thio-urethane bonding for both an indirect composite and a glass ceramic. Novel dual-cured composite cements containing thio-urethanes showed increased toughness, fracture toughness and

  18. The effect of dual tasking on foot kinematics in people with functional ankle instability.

    PubMed

    Tavakoli, Sanam; Forghany, Saeed; Nester, Christopher

    2016-09-01

    Some cases of repeated inversion ankle sprains are thought to have a neurological basis and are termed functional ankle instability (FAI). In addition to factors local to the ankle, such as loss of proprioception, cognitive demands have the ability to influence motor control and may increase the risk of repetitive lateral sprains. The purpose of this study was to investigate the effect of cognitive demand on foot kinematics in physically active people with functional ankle instability. 21 physically active participants with FAI and 19 matched healthy controls completed trials of normal walking (single task) and normal walking while performing a cognitive task (dual task). Foot motion relative to the shank was recorded. Cognitive performance, ankle kinematics and movement variability in single and dual task conditions was characterized. During normal walking, the ankle joint was significantly more inverted in FAI compared to the control group pre and post initial contact. Under dual task conditions, there was a statistically significant increase in frontal plane foot movement variability during the period 200ms pre and post initial contact in people with FAI compared to the control group (p<0.05). Dual task also significantly increased plantar flexion and inversion during the period 200ms pre and post initial contact in the FAI group (p<0.05). participants with FAI demonstrated different ankle movement patterns and increased movement variability during a dual task condition. Cognitive load may increase risk of ankle instability in these people. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Tetracyclines function as dual-action light-activated antibiotics.

    PubMed

    He, Ya; Huang, Ying-Ying; Xi, Liyan; Gelfand, Jeffrey A; Hamblin, Michael R

    2018-01-01

    Antimicrobial photodynamic inactivation (aPDI) employs photosensitizing dyes activated by visible light to produce reactive oxygen species. aPDI is independent of the antibiotic resistance status of the target cells, and is thought unlikely to produce resistance itself. Among many PS that have been investigated, tetracyclines occupy a unique niche. They are potentially dual-action compounds that can both kill bacteria under illumination, and prevent bacterial regrowth by inhibiting ribosomes. Tetracycline antibiotics are regarded as bacteriostatic rather than bactericidal. Doxycycline (DOTC) is excited best by UVA light (365 nm) while demeclocycline (DMCT) can be efficiently activated by blue light (415 nm) as well as UVA. Both compounds were able to eradicate Gram-positive (methicillin-resistant Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria (>6 log(10) steps of killing) at concentrations (10-50μM) and fluences (10-20J/cm2). In contrast to methylene blue, MB plus red light, tetracyclines photoinactivated bacteria in rich growth medium. When ~3 logs of bacteria were killed with DMCT/DOTC+light and the surviving cells were added to growth medium, further bacterial killing was observed, while the same experiment with MB allowed complete regrowth. MIC studies were carried out either in the dark or exposed to 0.5mW/cm2 blue light. Up to three extra steps (8-fold) increased antibiotic activity was found with light compared to dark, with MRSA and tetracycline-resistant strains of E. coli. Tetracyclines can accumulate in bacterial ribosomes, where they could be photoactivated with blue/UVA light producing microbial killing via ROS generation.

  20. TRICHLOROETHYLENE SORPTION AND OXIDATION USING A DUAL FUNCTION SORBENT/CATALYST IN A FALLING FURNACE REACTOR

    EPA Science Inventory

    A dual function medium (Cr-ZSM-5), capable of physisorbing trichloroethylene (TCE) at ambient temperature and catalytically oxidizing it at elevated temperature (-350 degrees C) was utilized in a novel continuous falling furnace reactor system to store and periodically destroy t...

  1. Properties and applications of chemically functionalized graphene.

    PubMed

    Craciun, M F; Khrapach, I; Barnes, M D; Russo, S

    2013-10-23

    The vast and yet largely unexplored family of graphene materials has great potential for future electronic devices with novel functionalities. The ability to engineer the electrical and optical properties in graphene by chemically functionalizing it with a molecule or adatom is widening considerably the potential applications targeted by graphene. Indeed, functionalized graphene has been found to be the best known transparent conductor or a wide gap semiconductor. At the same time, understanding the mechanisms driving the functionalization of graphene with hydrogen is proving to be of fundamental interest for energy storage devices. Here we discuss recent advances on the properties and applications of chemically functionalized graphene.

  2. The functional neuroanatomy of multitasking: combining dual tasking with a short term memory task.

    PubMed

    Deprez, Sabine; Vandenbulcke, Mathieu; Peeters, Ron; Emsell, Louise; Amant, Frederic; Sunaert, Stefan

    2013-09-01

    Insight into the neural architecture of multitasking is crucial when investigating the pathophysiology of multitasking deficits in clinical populations. Presently, little is known about how the brain combines dual-tasking with a concurrent short-term memory task, despite the relevance of this mental operation in daily life and the frequency of complaints related to this process, in disease. In this study we aimed to examine how the brain responds when a memory task is added to dual-tasking. Thirty-three right-handed healthy volunteers (20 females, mean age 39.9 ± 5.8) were examined with functional brain imaging (fMRI). The paradigm consisted of two cross-modal single tasks (a visual and auditory temporal same-different task with short delay), a dual-task combining both single tasks simultaneously and a multi-task condition, combining the dual-task with an additional short-term memory task (temporal same-different visual task with long delay). Dual-tasking compared to both individual visual and auditory single tasks activated a predominantly right-sided fronto-parietal network and the cerebellum. When adding the additional short-term memory task, a larger and more bilateral frontoparietal network was recruited. We found enhanced activity during multitasking in components of the network that were already involved in dual-tasking, suggesting increased working memory demands, as well as recruitment of multitask-specific components including areas that are likely to be involved in online holding of visual stimuli in short-term memory such as occipito-temporal cortex. These results confirm concurrent neural processing of a visual short-term memory task during dual-tasking and provide evidence for an effective fMRI multitasking paradigm. © 2013 Elsevier Ltd. All rights reserved.

  3. Functional Properties of Microorganisms in Fermented Foods

    PubMed Central

    Tamang, Jyoti P.; Shin, Dong-Hwa; Jung, Su-Jin; Chae, Soo-Wan

    2016-01-01

    Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers. PMID:27199913

  4. Dual Functions of Perirhinal Cortex in Fear Conditioning

    PubMed Central

    Kent, Brianne A.; Brown, Thomas H.

    2012-01-01

    The present review examines the role of perirhinal cortex (PRC) in Pavlovian fear conditioning. The focus is on rats, partly because so much is known, behaviorally and neurobiologically, about fear conditioning in these animals. In addition, the neuroanatomy and neurophysiology of rat PRC have been described in considerable detail at the cellular and systems levels. The evidence suggests that PRC can serve at least two types of mnemonic functions in Pavlovian fear conditioning. The first function, termed "stimulus unitization," refers to the ability to treat two or more separate items or stimulus elements as a single entity. Supporting evidence for this perceptual function comes from studies of context conditioning as well as delay conditioning to discontinuous auditory cues. In a delay paradigm, the conditional stimulus (CS) and unconditional stimulus (US) overlap temporally and co-terminate. The second PRC function entails a type of "transient memory." Supporting evidence comes from studies of trace cue conditioning, where there is a temporal gap or trace interval between the CS offset and the US onset. For learning to occur, there must be a transient CS representation during the trace interval. We advance a novel neurophysiological mechanism for this transient representation. These two hypothesized functions of PRC are consistent with inferences based on non-aversive forms of learning. PMID:22903623

  5. Dual-function beam splitter of a subwavelength fused-silica grating.

    PubMed

    Feng, Jijun; Zhou, Changhe; Zheng, Jiangjun; Cao, Hongchao; Lv, Peng

    2009-05-10

    We present the design and fabrication of a novel dual-function subwavelength fused-silica grating that can be used as a polarization-selective beam splitter. For TM polarization, the grating can be used as a two-port beam splitter at a wavelength of 1550 nm with a total diffraction efficiency of 98%. For TE polarization, the grating can function as a high-efficiency grating, and the diffraction efficiency of the -1st order is 95% under Littrow mounting. This dual-function grating design is based on a simplified modal method. By using the rigorous coupled-wave analysis, the optimum grating parameters can be determined. Holographic recording technology and inductively coupled plasma etching are used to manufacture the fused-silica grating. Experimental results are in agreement with the theoretical values.

  6. Dual drug release from hydrogels covalently containing polymeric micelles that possess different drug release properties.

    PubMed

    Murata, Mari; Uchida, Yusuke; Takami, Taku; Ito, Tomoki; Anzai, Ryosuke; Sonotaki, Seiichi; Murakami, Yoshihiko

    2017-05-01

    In the present study, we designed hydrogels for dual drug release: the hydrogels that covalently contained the polymeric micelles that possess different drug release properties. The hydrogels that were formed from polymeric micelles possessing a tightly packed (i.e., well-entangled) inner core exhibited a higher storage modulus than the hydrogels that were formed from the polymeric micelles possessing a loosely packed structure. Furthermore, we conducted release experiments and fluorescent observations to evaluate the profiles depicting the release of two compounds, rhodamine B and auramine O, from either polymeric micelles or hydrogels. According to our results, (1) hydrogels that covalently contains polymeric micelles that possess different drug release properties successfully exhibit the independent release behaviors of the two compounds and (2) fluorescence microscopy can greatly facilitate efforts to evaluate drug release properties of materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Manipulating the optical properties of dual implanted Au and Zn nanoparticles in sapphire

    NASA Astrophysics Data System (ADS)

    Epie, E. N.; Scott, D.; Chu, W. K.

    2017-11-01

    We have synthesized and manipulated the optical properties of metallic nanoparticles (NPs) by using a combination of low-energy high-fluence dual implantation and thermal annealing. We demonstrated that by implanting Zn before Au, the resulting absorption peak is enormously blue-shifted by 120 nm with respect to that of Au-only implanted samples. This magnitude of optical shift is not characteristic of unalloyed Au and to the best of our knowledge cannot be attributed to NP size change alone. On the other hand, the absorption peak for samples implanted with Au followed by Zn is blue-shifted about 20 nm. Additionally, by carefully annealing all implanted samples, both NP size distribution and corresponding optical properties can be further modified in a controlled manner. We attribute these behaviours to nanoalloy formation. This work provides a direct method for synthesizing and manipulating both the plasmonic and structural properties of metallic alloy NP in various transparent dielectrics for diverse applications.

  8. Properties and microstructures for dual alloy combinations of three superalloys with alloy 901

    NASA Technical Reports Server (NTRS)

    Harf, F. H.

    1985-01-01

    Dual alloy combinations have potential for use in aircraft engine components such as turbine disks where a wide range of stress and temperature regimes exists during operation. Such alloy combinations may directly result in the conservation of elements which are costly or not available domestically. Preferably, a uniform heat treatment yielding good properties for both alloys should be used. Dual alloy combinations of iron rich Alloy 901 with nickel base superalloys Rene 95, Astroloy, or MERL 76 were not isostatically pressed from prealloyed powders. Individual alloys, alloy mixtures, and layered alloy combinations were given the heat treatments specified for their use in turbine disks or appropriate for Alloy 901. Selected specimens were overaged for 1500 hr at 650 C. Metallographic examinations revealed the absence of phases not originally present in either alloy of a combination. Mechanical tests showed adequate properties in combinations of Rene 95 or Astroloy with Alloy 901 when given the Alloy 901 heat treatment. Combinations with MERL 76 had better properties when given the MERL 76 heat treatment. The results indicate that these combinations are promising candidates for use in turbine disks.

  9. An indecent proposal: the dual functions of indirect speech.

    PubMed

    Chakroff, Aleksandr; Thomas, Kyle A; Haque, Omar S; Young, Liane

    2015-01-01

    People often use indirect speech, for example, when trying to bribe a police officer by asking whether there might be "a way to take care of things without all the paperwork." Recent game theoretic accounts suggest that a speaker uses indirect speech to reduce public accountability for socially risky behaviors. The present studies examine a secondary function of indirect speech use: increasing the perceived moral permissibility of an action. Participants report that indirect speech is associated with reduced accountability for unethical behavior, as well as increased moral permissibility and increased likelihood of unethical behavior. Importantly, moral permissibility was a stronger mediator of the effect of indirect speech on likelihood of action, for judgments of one's own versus others' unethical action. In sum, the motorist who bribes the police officer with winks and nudges may not only avoid public punishment but also maintain the sense that his actions are morally permissible. Copyright © 2014 Cognitive Science Society, Inc.

  10. Optical and Scratch Resistant Properties of Diamondlike Carbon Films Deposited with Single and Dual Ion Beams

    NASA Technical Reports Server (NTRS)

    Kussmaul, Michael T.; Bogdanski, Michael S.; Banks, Bruce A.; Mirtich, Michael J.

    1993-01-01

    Amorphous diamond-like carbon (DLC) films were deposited using both single and dual ion beam techniques utilizing filament and hollow cathode ion sources. Continuous DLC films up to 3000 A thick were deposited on fused quartz plates. Ion beam process parameters were varied in an effort to create hard, clear films. Total DLC film absorption over visible wavelengths was obtained using a Perkin-Elmer spectrophotometer. An ellipsometer, with an Ar-He laser (wavelength 6328 A) was used to determine index of refraction for the DLC films. Scratch resistance, frictional, and adherence properties were determined for select films. Applications for these films range from military to the ophthalmic industries.

  11. Optical and scratch resistant properties of diamondlike carbon films deposited with single and dual ion beams

    NASA Technical Reports Server (NTRS)

    Kussmaul, Michael T.; Bogdanski, Michael S.; Banks, Bruce A.; Mirtich, Michael J.

    1993-01-01

    Amorphous diamondlike carbon (DLC) films were deposited using both single and dual ion beam techniques utilizing filament and hollow cathode ion sources. Continuous DLC films up to 3000 A thick were deposited on fused quartz plates. Ion beam process parameters were varied in an effort to create hard, clear films. Total DLC film absorption over visible wavelengths was obtained using a Perkin-Elmer spectrophotometer. An ellipsometer, with an Ar-He laser (wavelength 6328 A) was used to determine index of refraction for the DLC films. Scratch resistance and frictional and adherence properties were determined for select films. Applications for these films range from military to the ophthalmic industries.

  12. Dual Nerve Transfers for Restoration of Shoulder Function After Brachial Plexus Avulsion Injury.

    PubMed

    Chu, Bin; Wang, Huan; Chen, Liang; Gu, Yudong; Hu, Shaonan

    2016-06-01

    The purpose of this study was to investigate the effectiveness of shoulder function restoration by dual nerve transfers, spinal accessory nerve to the suprascapular nerve and 2 intercostal nerves to the anterior branch of the axillary nerve, in patients with shoulder paralysis that resulted from brachial plexus avulsion injury. It was a retrospective analysis to assess the impact of a variety of factors on reanimation of shoulder functions with dual nerve transfers. A total of 19 patients were included in this study. Most of these patients sustained avulsions of C5, C6, and C7 nerve roots (16 patients). Three of them had avulsions of C5 and C6 roots only. Through a posterior approach, direct coaptation of the intercostal nerves and the anterior branch of the axillary nerve was performed, along with accessory nerve transfer to the suprascapular nerve. Satisfactory shoulder function recovery (93.83° of shoulder abduction and 54.00° of external rotation on average) was achieved after a 62-month follow-up. This dual nerve transfer procedure provided us with a reliable and effective method for shoulder function reconstruction after brachial plexus root avulsion, especially C5/C6/C7 avulsion. The level of evidence is therapeutic IV.

  13. Properties of field functionals and characterization of local functionals

    NASA Astrophysics Data System (ADS)

    Brouder, Christian; Dang, Nguyen Viet; Laurent-Gengoux, Camille; Rejzner, Kasia

    2018-02-01

    Functionals (i.e., functions of functions) are widely used in quantum field theory and solid-state physics. In this paper, functionals are given a rigorous mathematical framework and their main properties are described. The choice of the proper space of test functions (smooth functions) and of the relevant concept of differential (Bastiani differential) are discussed. The relation between the multiple derivatives of a functional and the corresponding distributions is described in detail. It is proved that, in a neighborhood of every test function, the support of a smooth functional is uniformly compactly supported and the order of the corresponding distribution is uniformly bounded. Relying on a recent work by Dabrowski, several spaces of functionals are furnished with a complete and nuclear topology. In view of physical applications, it is shown that most formal manipulations can be given a rigorous meaning. A new concept of local functionals is proposed and two characterizations of them are given: the first one uses the additivity (or Hammerstein) property, the second one is a variant of Peetre's theorem. Finally, the first step of a cohomological approach to quantum field theory is carried out by proving a global Poincaré lemma and defining multi-vector fields and graded functionals within our framework.

  14. 49 CFR 369.1 - Annual reports of motor carriers of property, motor carriers of household goods, and dual...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Annual reports of motor carriers of property, motor carriers of household goods, and dual property carriers. 369.1 Section 369.1 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER...

  15. Dual descriptors within the framework of spin-polarized density functional theory.

    PubMed

    Chamorro, E; Pérez, P; Duque, M; De Proft, F; Geerlings, P

    2008-08-14

    Spin-polarized density functional theory (SP-DFT) allows both the analysis of charge-transfer (e.g., electrophilic and nucleophilic reactivity) and of spin-polarization processes (e.g., photophysical changes arising from electron transitions). In analogy with the dual descriptor introduced by Morell et al. [J. Phys. Chem. A 109, 205 (2005)], we introduce new dual descriptors intended to simultaneously give information of the molecular regions where the spin-polarization process linking states of different multiplicity will drive electron density and spin density changes. The electronic charge and spin rearrangement in the spin forbidden radiative transitions S(0)-->T(n,pi(*)) and S(0)-->T(pi,pi(*)) in formaldehyde and ethylene, respectively, have been used as benchmark examples illustrating the usefulness of the new spin-polarization dual descriptors. These quantities indicate those regions where spin-orbit coupling effects are at work in such processes. Additionally, the qualitative relationship between the topology of the spin-polarization dual descriptors and the vertical singlet triplet energy gap in simple substituted carbene series has been also discussed. It is shown that the electron density and spin density rearrangements arise in agreement with spectroscopic experimental evidence and other theoretical results on the selected target systems.

  16. Structure, function and translational relevance of aquaporin dual water and ion channels.

    PubMed

    Yool, Andrea J; Campbell, Ewan M

    2012-01-01

    Aquaporins have been assumed to be selective for water alone, and aquaglyceroporins are accepted as carrying water and small uncharged solutes including glycerol. This review presents an expanded view of aquaporins as channels with more complex mechanisms of regulation and diverse repertoires of substrate permeabilities than were originally appreciated in the early establishment of the field. The role of aquaporins as dual water and gated ion channels is likely to have physiological and potentially translational relevance, and can be evaluated with newly developed molecular and pharmacological tools. Ion channel activity has been shown for Aquaporins -0, -1, and -6, Drosphila Big Brain, and plant Nodulin-26. Although the concept of ion channel function in aquaporins remains controversial, research advances are beginning to define not only the ion channel function but also the detailed molecular mechanisms that govern and mediate the multifunctional capabilities. With regard to physiological relevance, the adaptive benefit of expression of ion channel activity in aquaporins, implied by amino acid sequence conservation of the ion channel gating domains, suggests they provide more than water or glycerol and solute transport. Dual ion and water channels are of interest for understanding the modulation of transmembrane fluid gradients, volume regulation, and possible signal transduction in tissues expressing classes of aquaporins that have the dual function capability. Other aquaporin classes might be found in future work to have ion channel activities, pending identification of the possible signaling pathways that could govern activation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Production Functions for Water Delivery Systems: Analysis and Estimation Using Dual Cost Function and Implicit Price Specifications

    NASA Astrophysics Data System (ADS)

    Teeples, Ronald; Glyer, David

    1987-05-01

    Both policy and technical analysis of water delivery systems have been based on cost functions that are inconsistent with or are incomplete representations of the neoclassical production functions of economics. We present a full-featured production function model of water delivery which can be estimated from a multiproduct, dual cost function. The model features implicit prices for own-water inputs and is implemented as a jointly estimated system of input share equations and a translog cost function. Likelihood ratio tests are performed showing that a minimally constrained, full-featured production function is a necessary specification of the water delivery operations in our sample. This, plus the model's highly efficient and economically correct parameter estimates, confirms the usefulness of a production function approach to modeling the economic activities of water delivery systems.

  18. Multi-functional angiographic OFDI using frequency-multiplexed dual-beam illumination

    PubMed Central

    Kim, SunHee; Park, Taejin; Jang, Sun-Joo; Nam, Ahhyun S.; Vakoc, Benjamin J.; Oh, Wang-Yuhl

    2015-01-01

    Detection of blood flow inside the tissue sample can be achieved by measuring the local change of complex signal over time in angiographic optical coherence tomography (OCT). In conventional angiographic OCT, the transverse displacement of the imaging beam during the time interval between a pair of OCT signal measurements must be significantly reduced to minimize the noise due to the beam scanning-induced phase decorrelation at the expense of the imaging speed. Recent introduction of dual-beam scan method either using polarization encoding or two identical imaging systems in spectral-domain (SD) OCT scheme shows potential for high-sensitivity vasculature imaging without suffering from spurious phase noise caused by the beam scanning-induced spatial decorrelation. In this paper, we present multi-functional angiographic optical frequency domain imaging (OFDI) using frequency-multiplexed dual-beam illumination. This frequency multiplexing scheme, utilizing unique features of OFDI, provides spatially separated dual imaging beams occupying distinct electrical frequency bands that can be demultiplexed in the frequency domain processing. We demonstrate the 3D multi-functional imaging of the normal mouse skin in the dorsal skin fold chamber visualizing distinct layer structures from the intensity imaging, information about mechanical integrity from the polarization-sensitive imaging, and depth-resolved microvasculature from the angiographic imaging that are simultaneously acquired and automatically co-registered. PMID:25968731

  19. Memory for pictures and words as a function of level of processing: Depth or dual coding?

    PubMed

    D'Agostino, P R; O'Neill, B J; Paivio, A

    1977-03-01

    The experiment was designed to test differential predictions derived from dual-coding and depth-of-processing hypotheses. Subjects under incidental memory instructions free recalled a list of 36 test events, each presented twice. Within the list, an equal number of events were assigned to structural, phonemic, and semantic processing conditions. Separate groups of subjects were tested with a list of pictures, concrete words, or abstract words. Results indicated that retention of concrete words increased as a direct function of the processing-task variable (structural < phonemic dual-coding model.

  20. Vital Soil: Function, Value and Properties.

    USDA-ARS?s Scientific Manuscript database

    This article is a review of the book, Vital Soil: Function, Value and Properties. Soil vitality has been defined as the ability of soil ecosystems to stay in balance in a changing world. The soil environment and the life that it supports developed over centuries and millennia, but careless human ac...

  1. Functionalized coronenes: synthesis, solid structure, and properties.

    PubMed

    Wu, Di; Zhang, Hua; Liang, Jinhua; Ge, Haojie; Chi, Chunyan; Wu, Jishan; Liu, Sheng Hua; Yin, Jun

    2012-12-21

    The construction of coronenes using simple building blocks is a challenging task. In this work, triphenylene was used as a building block to construct functionalized coronenes, and their solid structures and optoelectronic properties were investigated. The single crystal structures showed that coronenes have different packing motifs. Their good solubility and photostability make them potential solution-processable candidates for organic devices.

  2. The Theory of Propellers I : Determination of the Circulation Function and the Mass Coefficient for Dual-Rotating Propellers

    NASA Technical Reports Server (NTRS)

    Theodorsen, Theodore

    1944-01-01

    Values of the circulation function have been obtained for dual-rotating propellers. Numerical values are given for four, eight, and twelve-blade dual-rotating propellers and for advance ratios from 2 to about 6. In addition, the circulation function has been determine for single-rotating propellers for the higher values of the advance ratio. The mass coefficient, another quantity of significance in propeller theory, has been introduced.

  3. Feasibility study analysis for multi-function dual energy oven (case study: tapioca crackers small medium enterprise)

    NASA Astrophysics Data System (ADS)

    Soraya, N. W.; El Hadi, R. M.; Chumaidiyah, E.; Tripiawan, W.

    2017-12-01

    Conventional drying process is constrained by weather (cloudy / rainy), and requires wide drying area, and provides low-quality product. Multi-function dual energy oven is the appropriate technology to solve these problems. The oven uses solar thermal or gas heat for drying various type of products, including tapioca crackers. Investment analysis in technical, operational, and financial aspects show that the multi-function dual energy oven is feasible to be implemented for small medium enterprise (SME) processing tapioca crackers.

  4. Nanogenerator-based dual-functional and self-powered thin patch loudspeaker or microphone for flexible electronics.

    PubMed

    Li, Wei; Torres, David; Díaz, Ramón; Wang, Zhengjun; Wu, Changsheng; Wang, Chuan; Lin Wang, Zhong; Sepúlveda, Nelson

    2017-05-16

    Ferroelectret nanogenerators were recently introduced as a promising alternative technology for harvesting kinetic energy. Here we report the device's intrinsic properties that allow for the bidirectional conversion of energy between electrical and mechanical domains; thus extending its potential use in wearable electronics beyond the power generation realm. This electromechanical coupling, combined with their flexibility and thin film-like form, bestows dual-functional transducing capabilities to the device that are used in this work to demonstrate its use as a thin, wearable and self-powered loudspeaker or microphone patch. To determine the device's performance and applicability, sound pressure level is characterized in both space and frequency domains for three different configurations. The confirmed device's high performance is further validated through its integration in three different systems: a music-playing flag, a sound recording film and a flexible microphone for security applications.

  5. Nanogenerator-based dual-functional and self-powered thin patch loudspeaker or microphone for flexible electronics

    NASA Astrophysics Data System (ADS)

    Li, Wei; Torres, David; Díaz, Ramón; Wang, Zhengjun; Wu, Changsheng; Wang, Chuan; Lin Wang, Zhong; Sepúlveda, Nelson

    2017-05-01

    Ferroelectret nanogenerators were recently introduced as a promising alternative technology for harvesting kinetic energy. Here we report the device's intrinsic properties that allow for the bidirectional conversion of energy between electrical and mechanical domains; thus extending its potential use in wearable electronics beyond the power generation realm. This electromechanical coupling, combined with their flexibility and thin film-like form, bestows dual-functional transducing capabilities to the device that are used in this work to demonstrate its use as a thin, wearable and self-powered loudspeaker or microphone patch. To determine the device's performance and applicability, sound pressure level is characterized in both space and frequency domains for three different configurations. The confirmed device's high performance is further validated through its integration in three different systems: a music-playing flag, a sound recording film and a flexible microphone for security applications.

  6. Nanogenerator-based dual-functional and self-powered thin patch loudspeaker or microphone for flexible electronics

    PubMed Central

    Li, Wei; Torres, David; Díaz, Ramón; Wang, Zhengjun; Wu, Changsheng; Wang, Chuan; Lin Wang, Zhong; Sepúlveda, Nelson

    2017-01-01

    Ferroelectret nanogenerators were recently introduced as a promising alternative technology for harvesting kinetic energy. Here we report the device's intrinsic properties that allow for the bidirectional conversion of energy between electrical and mechanical domains; thus extending its potential use in wearable electronics beyond the power generation realm. This electromechanical coupling, combined with their flexibility and thin film-like form, bestows dual-functional transducing capabilities to the device that are used in this work to demonstrate its use as a thin, wearable and self-powered loudspeaker or microphone patch. To determine the device's performance and applicability, sound pressure level is characterized in both space and frequency domains for three different configurations. The confirmed device's high performance is further validated through its integration in three different systems: a music-playing flag, a sound recording film and a flexible microphone for security applications. PMID:28508862

  7. Storage and retrieval properties of dual codes for pictures and words in recognition memory.

    PubMed

    Snodgrass, J G; McClure, P

    1975-09-01

    Storage and retrieval properties of pictures and words were studied within a recognition memory paradigm. Storage was manipulated by instructing subjects either to image or to verbalize to both picture and word stimuli during the study sequence. Retrieval was manipulated by representing a proportion of the old picture and word items in their opposite form during the recognition test (i.e., some old pictures were tested with their corresponding words and vice versa). Recognition performance for pictures was identical under the two instructional conditions, whereas recognition performance for words was markedly superior under the imagery instruction condition. It was suggested that subjects may engage in dual coding of simple pictures naturally, regardless of instructions, whereas dual coding of words may occur only under imagery instructions. The form of the test item had no effect on recognition performance for either type of stimulus and under either instructional condition. However, change of form of the test item markedly reduced item-by-item correlations between the two instructional conditions. It is tentatively proposed that retrieval is required in recognition, but that the effect of a form change is simply to make the retrieval process less consistent, not less efficient.

  8. [A process of aquatic ecological function regionalization: The dual tree framework and conceptual model].

    PubMed

    Guo, Shu Hai; Wu, Bo

    2017-12-01

    Aquatic ecological regionalization and aquatic ecological function regionalization are the basis of water environmental management of a river basin and rational utilization of an aquatic ecosystem, and have been studied in China for more than ten years. Regarding the common problems in this field, the relationship between aquatic ecological regionalization and aquatic ecological function regionalization was discussed in this study by systematic analysis of the aquatic ecological zoning and the types of aquatic ecological function. Based on the dual tree structure, we put forward the RFCH process and the diamond conceptual model. Taking Liaohe River basin as an example and referring to the results of existing regionalization studies, we classified the aquatic ecological function regions based on three-class aquatic ecological regionalization. This study provided a process framework for aquatic ecological function regionalization of a river basin.

  9. Psychometric Functions of Dual-Task Paradigms for Measuring Listening Effort.

    PubMed

    Wu, Yu-Hsiang; Stangl, Elizabeth; Zhang, Xuyang; Perkins, Joanna; Eilers, Emily

    The purpose of the study was to characterize the psychometric functions that describe task performance in dual-task listening effort measures as a function of signal to noise ratio (SNR). Younger adults with normal hearing (YNH, n = 24; experiment 1) and older adults with hearing impairment (n = 24; experiment 2) were recruited. Dual-task paradigms wherein the participants performed a primary speech recognition task simultaneously with a secondary task were conducted at a wide range of SNRs. Two different secondary tasks were used: an easy task (i.e., a simple visual reaction-time task) and a hard task (i.e., the incongruent Stroop test). The reaction time (RT) quantified the performance of the secondary task. For both participant groups and for both easy and hard secondary tasks, the curves that described the RT as a function of SNR were peak shaped. The RT increased as SNR changed from favorable to intermediate SNRs, and then decreased as SNRs moved from intermediate to unfavorable SNRs. The RT reached its peak (longest time) at the SNRs at which the participants could understand 30 to 50% of the speech. In experiments 1 and 2, the dual-task trials that had the same SNR were conducted in one block. To determine if the peak shape of the RT curves was specific to the blocked SNR presentation order used in these experiments, YNH participants were recruited (n = 25; experiment 3) and dual-task measures, wherein the SNR was varied from trial to trial (i.e., nonblocked), were conducted. The results indicated that, similar to the first two experiments, the RT curves had a peak shape. Secondary task performance was poorer at the intermediate SNRs than at the favorable and unfavorable SNRs. This pattern was observed for both YNH and older adults with hearing impairment participants and was not affected by either task type (easy or hard secondary task) or SNR presentation order (blocked or nonblocked). The shorter RT at the unfavorable SNRs (speech intelligibility < 30

  10. Determining Reliability of a Dual-Task Functional Mobility Protocol for Individuals With Lower Extremity Amputation.

    PubMed

    Hunter, Susan W; Frengopoulos, Courtney; Holmes, Jeff; Viana, Ricardo; Payne, Michael W

    2018-04-01

    To determine the relative and absolute reliability of a dual-task functional mobility assessment. Cross-sectional study. Academic rehabilitation hospital. Individuals (N=60) with lower extremity amputation attending an outpatient amputee clinic (mean age, 58.21±12.59y; 18, 80% male) who were stratified into 3 groups: (1) transtibial amputation of vascular etiology (n=20); (2) transtibial amputation of nonvascular etiology (n=20); and (3) transfemoral or bilateral amputation of any etiology (n=20). Not applicable. Time to complete the L Test measured functional mobility under single- and dual-task conditions. The addition of a cognitive task (serial subtractions by 3's) created dual-task conditions. Single-task performance on the cognitive task was also reported. Intraclass correlation coefficients (ICCs) measured relative reliability; SEM and minimal detectable change with a 95% confidence interval (MDC 95 ) measured absolute reliability. Bland-Altman plots measured agreement between assessments. Relative reliability results were excellent for all 3 groups. Values for the dual-task L Test for those with transtibial amputation of vascular etiology (n=20; mean age, 60.36±7.84y; 19, 90% men) were ICC=.98 (95% confidence interval [CI], .94-.99), SEM=1.36 seconds, and MDC 95 =3.76 seconds; for those with transtibial amputation of nonvascular etiology (n=20; mean age, 55.85±14.08y; 17, 85% men), values were ICC=.93 (95% CI, .80-.98), SEM=1.34 seconds, and MDC 95 =3.71 seconds; and for those with transfemoral or bilateral amputation (n=20; mean age, 58.21±14.88y; 13, 65% men), values were ICC=.998 (95% CI, .996-.999), SEM=1.03 seconds, and MDC 95 =2.85 seconds. Bland-Altman plots indicated that assessments did not vary systematically for each group. This dual-task assessment protocol achieved approved levels of relative reliability values for the 3 groups tested. This protocol may be used clinically or in research settings to assess the interaction between cognition

  11. Effects of Dual-Channel Functional Electrical Stimulation on Gait Performance in Patients with Hemiparesis

    PubMed Central

    Springer, Shmuel; Vatine, Jean-Jacques; Lipson, Ronit; Wolf, Alon; Laufer, Yocheved

    2012-01-01

    The study objective was to assess the effect of functional electrical stimulation (FES) applied to the peroneal nerve and thigh muscles on gait performance in subjects with hemiparesis. Participants were 45 subjects (age 57.8 ± 14.8 years) with hemiparesis (5.37 ± 5.43 years since diagnosis) demonstrating a foot-drop and impaired knee control. Thigh stimulation was applied either to the quadriceps or hamstrings muscles, depending on the dysfunction most affecting gait. Gait was assessed during a two-minute walk test with/without stimulation and with peroneal stimulation alone. A second assessment was conducted after six weeks of daily use. The addition of thigh muscles stimulation to peroneal stimulation significantly enhanced gait velocity measures at the initial and second evaluation. Gait symmetry was enhanced by the dual-channel stimulation only at the initial evaluation, and single-limb stance percentage only at the second assessment. For example, after six weeks, the two-minute gait speed with peroneal stimulation and with the dual channel was 0.66 ± 0.30 m/sec and 0.70 ± 0.31 m/sec, respectively (P < 0.0001). In conclusion, dual-channel FES may enhance gait performance in subjects with hemiparesis more than peroneal FES alone. PMID:23097635

  12. Continuous Dual Resetting of the Immune Repertoire as a Basic Principle of the Immune System Function.

    PubMed

    Balzar, Silvana

    2017-01-01

    Idiopathic chronic inflammatory conditions (ICIC) such as allergy, asthma, chronic obstructive pulmonary disease, and various autoimmune conditions are a worldwide health problem. Understanding the pathogenesis of ICIC is essential for their successful therapy and prevention. However, efforts are hindered by the lack of comprehensive understanding of the human immune system function. In line with those efforts, described here is a concept of stochastic continuous dual resetting (CDR) of the immune repertoire as a basic principle that governs the function of immunity. The CDR functions as a consequence of system's thermodynamically determined intrinsic tendency to acquire new states of inner equilibrium and equilibrium against the environment. Consequently, immune repertoire undergoes continuous dual (two-way) resetting: against the physiologic continuous changes of self and against the continuously changing environment. The CDR-based dynamic concept of immunity describes mechanisms of self-regulation, tolerance, and immunosenescence, and emphasizes the significance of immune system's compartmentalization in the pathogenesis of ICIC. The CDR concept's relative simplicity and concomitantly documented congruency with empirical, clinical, and experimental data suggest it may represent a plausible theoretical framework to better understand the human immune system function.

  13. Microscale characterization of the viscoelastic properties of hydrogel biomaterials using dual-mode ultrasound elastography.

    PubMed

    Hong, Xiaowei; Stegemann, Jan P; Deng, Cheri X

    2016-05-01

    Characterization of the microscale mechanical properties of biomaterials is a key challenge in the field of mechanobiology. Dual-mode ultrasound elastography (DUE) uses high frequency focused ultrasound to induce compression in a sample, combined with interleaved ultrasound imaging to measure the resulting deformation. This technique can be used to non-invasively perform creep testing on hydrogel biomaterials to characterize their viscoelastic properties. DUE was applied to a range of hydrogel constructs consisting of either hydroxyapatite (HA)-doped agarose, HA-collagen, HA-fibrin, or preosteoblast-seeded collagen constructs. DUE provided spatial and temporal mapping of local and bulk displacements and strains at high resolution. Hydrogel materials exhibited characteristic creep behavior, and the maximum strain and residual strain were both material- and concentration-dependent. Burger's viscoelastic model was used to extract characteristic parameters describing material behavior. Increased protein concentration resulted in greater stiffness and viscosity, but did not affect the viscoelastic time constant of acellular constructs. Collagen constructs exhibited significantly higher modulus and viscosity than fibrin constructs. Cell-seeded collagen constructs became stiffer with altered mechanical behavior as they developed over time. Importantly, DUE also provides insight into the spatial variation of viscoelastic properties at sub-millimeter resolution, allowing interrogation of the interior of constructs. DUE presents a novel technique for non-invasively characterizing hydrogel materials at the microscale, and therefore may have unique utility in the study of mechanobiology and the characterization of hydrogel biomaterials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Microscale Characterization of the Viscoelastic Properties of Hydrogel Biomaterials using Dual-Mode Ultrasound Elastography

    PubMed Central

    Hong, Xiaowei; Stegemann, Jan P.; Deng, Cheri X.

    2016-01-01

    Characterization of the microscale mechanical properties of biomaterials is a key challenge in the field of mechanobiology. Dual-mode ultrasound elastography (DUE) uses high frequency focused ultrasound to induce compression in a sample, combined with interleaved ultrasound imaging to measure the resulting deformation. This technique can be used to non-invasively perform creep testing on hydrogel biomaterials to characterize their viscoelastic properties. DUE was applied to a range of hydrogel constructs consisting of either hydroxyapatite (HA)-doped agarose, HA-collagen, HA-fibrin, or preosteoblast-seeded collagen constructs. DUE provided spatial and temporal mapping of local and bulk displacements and strains at high resolution. Hydrogel materials exhibited characteristic creep behavior, and the maximum strain and residual strain were both material- and concentration-dependent. Burger’s viscoelastic model was used to extract characteristic parameters describing material behavior. Increased protein concentration resulted in greater stiffness and viscosity, but did not affect the viscoelastic time constant of acellular constructs. Collagen constructs exhibited significantly higher modulus and viscosity than fibrin constructs. Cell-seeded collagen constructs became stiffer with altered mechanical behavior as they developed over time. Importantly, DUE also provides insight into the spatial variation of viscoelastic properties at sub-millimeter resolution, allowing interrogation of the interior of constructs. DUE presents a novel technique for non-invasively characterizing hydrogel materials at the microscale, and therefore may have unique utility in the study of mechanobiology and the characterization of hydrogel biomaterials. PMID:26928595

  15. Retrieve Optically Thick Ice Cloud Microphysical Properties by Using Airborne Dual-Wavelength Radar Measurements

    NASA Technical Reports Server (NTRS)

    Wang, Zhien; Heymsfield, Gerald M.; Li, Lihua; Heymsfield, Andrew J.

    2005-01-01

    An algorithm to retrieve optically thick ice cloud microphysical property profiles is developed by using the GSFC 9.6 GHz ER-2 Doppler Radar (EDOP) and the 94 GHz Cloud Radar System (CRS) measurements aboard the high-altitude ER-2 aircraft. In situ size distribution and total water content data from the CRYSTAL-FACE field campaign are used for the algorithm development. To reduce uncertainty in calculated radar reflectivity factors (Ze) at these wavelengths, coincident radar measurements and size distribution data are used to guide the selection of mass-length relationships and to deal with the density and non-spherical effects of ice crystals on the Ze calculations. The algorithm is able to retrieve microphysical property profiles of optically thick ice clouds, such as, deep convective and anvil clouds, which are very challenging for single frequency radar and lidar. Examples of retrieved microphysical properties for a deep convective clouds are presented, which show that EDOP and CRS measurements provide rich information to study cloud structure and evolution. Good agreement between IWPs derived from an independent submillimeter-wave radiometer, CoSSIR, and dual-wavelength radar measurements indicates accuracy of the IWC retrieved from the two-frequency radar algorithm.

  16. Hydroxyapatite nanobelt/polylactic acid Janus membrane with osteoinduction/barrier dual functions for precise bone defect repair.

    PubMed

    Ma, Baojin; Han, Jing; Zhang, Shan; Liu, Feng; Wang, Shicai; Duan, Jiazhi; Sang, Yuanhua; Jiang, Huaidong; Li, Dong; Ge, Shaohua; Yu, Jinghua; Liu, Hong

    2018-04-15

    Controllable osteoinduction maintained in the original defect area is the key to precise bone repair. To meet the requirement of precise bone regeneration, a hydroxyapatite (HAp) nanobelt/polylactic acid (PLA) (HAp/PLA) Janus membrane has been successfully prepared in this study by coating PLA on a paper-like HAp nanobelt film by a casting-pervaporation method. The Janus membrane possesses dual functions: excellent osteoinduction from the hydrophilic HAp nanobelt side and barrier function originating from the hydrophobic PLA film. The cell viability and osteogenic differentiation ability of human adipose-derived stem cells (hADSCs) on the Janus membrane were assessed. The in vitro experimental results prove that the HAp nanobelt side presents high cell viability and efficient osteoinduction without any growth factor and that the PLA side can prohibit cell attachment. The in vivo repair experiments on a rat mandible defect model prove that the PLA side can prevent postoperative adhesion between bone and adjacent soft tissues. Most importantly, the HAp side has a strong ability to promote defect repair and bone regeneration. Therefore, the HAp/PLA Janus membrane will have wide applications as a kind of tissue engineering material in precise bone repair because of its unique dual osteoinduction/barrier functions, biocompatibility, low cost, and its ability to be mass-produced. Precise bone defect repair to keeping tissue integrity and original outline shape is a very important issue for tissue engineering. Here, we have designed and prepared a novel HAp/PLA Janus membrane using a casting-pervaporation method to form a layer of PLA film on paper-like HAp nanobelt film. HAp nanobelt side of the Janus membrane can successfully promote osteogenic differentiation. PLA side of the Janus membrane exhibits good properties as a barrier for preventing the adhesion of cells in vitro. Mandible repair experiments in vivo have shown that the HAp/PLA Janus membrane can promote rat

  17. HAMLET: functional properties and therapeutic potential.

    PubMed

    Ho C S, James; Rydström, Anna; Trulsson, Maria; Bålfors, Johannes; Storm, Petter; Puthia, Manoj; Nadeem, Aftab; Svanborg, Catharina

    2012-10-01

    Human α-lactalbumin made lethal to tumor cells (HAMLET) is the first member in a new family of protein-lipid complexes that kills tumor cells with high selectivity. The protein component of HAMLET is α-lactalbumin, which in its native state acts as a substrate specifier in the lactose synthase complex, thereby defining a function essential for the survival of lactating mammals. In addition, α-lactalbumin acquires tumoricidal activity after partial unfolding and binding to oleic acid. The lipid cofactor serves the dual role as a stabilizer of the altered fold of the protein and a coactivator of specific steps in tumor cell death. HAMLET is broadly tumoricidal, suggesting that the complex identifies conserved death pathways suitable for targeting by novel therapies. Sensitivity to HAMLET is defined by oncogene expression including Ras and c-Myc and by glycolytic enzymes. Cellular targets are located in the cytoplasmic membrane, cytoskeleton, mitochondria, proteasomes, lysosomes and nuclei, and specific signaling pathways are rapidly activated, first by interactions of HAMLET with the cell membrane and subsequently after HAMLET internalization. Therapeutic effects of HAMLET have been demonstrated in human skin papillomas and bladder cancers, and HAMLET limits the progression of human glioblastomas, with no evidence of toxicity for normal brain or bladder tissue. These findings open up new avenues for cancer therapy and the understanding of conserved death responses in tumor cells.

  18. DC and analog/RF performance optimisation of source pocket dual work function TFET

    NASA Astrophysics Data System (ADS)

    Raad, Bhagwan Ram; Sharma, Dheeraj; Kondekar, Pravin; Nigam, Kaushal; Baronia, Sagar

    2017-12-01

    We investigate a systematic study of source pocket tunnel field-effect transistor (SP TFET) with dual work function of single gate material by using uniform and Gaussian doping profile in the drain region for ultra-low power high frequency high speed applications. For this, a n+ doped region is created near the source/channel junction to decrease the depletion width results in improvement of ON-state current. However, the dual work function of the double gate is used for enhancement of the device performance in terms of DC and analog/RF parameters. Further, to improve the high frequency performance of the device, Gaussian doping profile is considered in the drain region with different characteristic lengths which decreases the gate to drain capacitance and leads to drastic improvement in analog/RF figures of merit. Furthermore, the optimisation is performed with different concentrations for uniform and Gaussian drain doping profile and for various sectional length of lower work function of the gate electrode. Finally, the effect of temperature variation on the device performance is demonstrated.

  19. Silver nanoparticles-containing dual-function hydrogels based on a guar gum-sodium borohydride system

    PubMed Central

    Dai, Lei; Nadeau, Ben; An, Xingye; Cheng, Dong; Long, Zhu; Ni, Yonghao

    2016-01-01

    Dual-function hydrogels, possessing both stimuli-responsive and self-healing properties, have recently attracted attention of both chemists and materials scientists. Here we report a new paradigm using natural polymer (guar gum, GG) and sodium borohydride (NaBH4), for the preparation of silver nanoparticles (AgNPs)-containing smart hydrogels in a simple, fast and economical way. NaBH4 performs as a reducing agent for AgNPs synthesis using silver nitrate (AgNO3) as the precursor. Meanwhile, sodium metaborate (NaBO2) (from NaBH4) behaves as a cross-linking agent between GG molecular chains. The AgNPs/GG hydrogels with excellent viscoelastic properties can be obtained within 3 min at room temperature without the addition of other cross-linkers. The resultant AgNPs/GG hydrogels are flowable and injectable, and they possess excellent pH/thermal responsive properties. Additionally, they exhibit rapid self-healing capacity. This work introduces a facile and scale-up way to prepare a class of hydrogels that can have great potential to biomedical and other industrial applications. PMID:27819289

  20. Surface properties of functional polymer systems

    NASA Astrophysics Data System (ADS)

    Wong, Derek

    Polymer surface modification typically involves blending with other polymers or chemical modification of the parent polymer. Such strategies inevitably result in polymer systems that are spatially and chemically heterogeneous, and which exhibit the phenomenon of surface segregation. This work investigates the effects of chain architecture on the surface segregation behavior of such functionally modified polymers using a series of end- and center-fluorinated poly(D,L-lactide). Surface segregation of the fluorinated functional groups was observed in both chain architectures via AMPS and water contact angle. Higher surface segregation was noted for functional groups located at the chain end as opposed to those in the middle of the chain. A self-consistent mean-field lattice theory was used to model the composition depth profiles of functional groups and excellent agreement was found between the model predictions and the experimental AMPS data in both chain architectures. Polymer properties are also in general dependent on both time and temperature, and exhibit a range of relaxation times in response to environmental stimuli. This behavior arises from the characteristic frequencies of molecular motions of the polymer chain and the interrelationship between time and temperature has been widely established for polymer bulk properties. There is evidence that surface properties also respond in a manner that is time and temperature dependent and that this dependence may not be the same as that observed for bulk properties. AMPS and water contact angle experiments were used to investigate the surface reorganization behavior of functional groups using a series of anionically synthesized end-fluorinated and end-carboxylated poly(styrene). It was found that both types of functional end-groups reorganized upon a change in the polarity of the surface environment in order to minimize the surface free energy. ADXPS and contact angle results suggest that the reorganization depth was

  1. Influence of Sequential vs. Simultaneous Dual-Task Exercise Training on Cognitive Function in Older Adults.

    PubMed

    Tait, Jamie L; Duckham, Rachel L; Milte, Catherine M; Main, Luana C; Daly, Robin M

    2017-01-01

    Emerging research indicates that exercise combined with cognitive training may improve cognitive function in older adults. Typically these programs have incorporated sequential training, where exercise and cognitive training are undertaken separately. However, simultaneous or dual-task training, where cognitive and/or motor training are performed simultaneously with exercise, may offer greater benefits. This review summary provides an overview of the effects of combined simultaneous vs. sequential training on cognitive function in older adults. Based on the available evidence, there are inconsistent findings with regard to the cognitive benefits of sequential training in comparison to cognitive or exercise training alone. In contrast, simultaneous training interventions, particularly multimodal exercise programs in combination with secondary tasks regulated by sensory cues, have significantly improved cognition in both healthy older and clinical populations. However, further research is needed to determine the optimal characteristics of a successful simultaneous training program for optimizing cognitive function in older people.

  2. Influence of Sequential vs. Simultaneous Dual-Task Exercise Training on Cognitive Function in Older Adults

    PubMed Central

    Tait, Jamie L.; Duckham, Rachel L.; Milte, Catherine M.; Main, Luana C.; Daly, Robin M.

    2017-01-01

    Emerging research indicates that exercise combined with cognitive training may improve cognitive function in older adults. Typically these programs have incorporated sequential training, where exercise and cognitive training are undertaken separately. However, simultaneous or dual-task training, where cognitive and/or motor training are performed simultaneously with exercise, may offer greater benefits. This review summary provides an overview of the effects of combined simultaneous vs. sequential training on cognitive function in older adults. Based on the available evidence, there are inconsistent findings with regard to the cognitive benefits of sequential training in comparison to cognitive or exercise training alone. In contrast, simultaneous training interventions, particularly multimodal exercise programs in combination with secondary tasks regulated by sensory cues, have significantly improved cognition in both healthy older and clinical populations. However, further research is needed to determine the optimal characteristics of a successful simultaneous training program for optimizing cognitive function in older people. PMID:29163146

  3. Dual function of MG53 in membrane repair and insulin signaling

    PubMed Central

    Tan, Tao; Ko, Young-Gyu; Ma, Jianjie

    2016-01-01

    MG53 is a member of the TRIM-family protein that acts as a key component of the cell membrane repair machinery. MG53 is also an E3-ligase that ubiquinates insulin receptor substrate-1 and controls insulin signaling in skeletal muscle cells. Since its discovery in 2009, research efforts have been devoted to translate this basic discovery into clinical applications in human degenerative and metabolic diseases. This review article highlights the dual function of MG53 in cell membrane repair and insulin signaling, the mechanism that underlies the control of MG53 function, and the therapeutic value of targeting MG53 function in regenerative medicine. [BMB Reports 2016; 49(8): 414-423] PMID:27174502

  4. Development of a patch type embedded cardiac function monitoring system using dual microprocessor for arrhythmia detection in heart disease patient.

    PubMed

    Jang, Yongwon; Noh, Hyung Wook; Lee, I B; Jung, Ji-Wook; Song, Yoonseon; Lee, Sooyeul; Kim, Seunghwan

    2012-01-01

    A patch type embedded cardiac function monitoring system was developed to detect arrhythmias such as PVC (Premature Ventricular Contraction), pause, ventricular fibrillation, and tachy/bradycardia. The overall system is composed of a main module including a dual processor and a Bluetooth telecommunication module. The dual microprocessor strategy minimizes power consumption and size, and guarantees the resources of embedded software programs. The developed software was verified with standard DB, and showed good performance.

  5. A Modular Dual-Labeling Scaffold That Retains Agonistic Properties for Somatostatin Receptor Targeting

    PubMed Central

    Ghosh, Sukhen C.; Rodriguez, Melissa; Carmon, Kendra S.; Voss, Julie; Wilganowski, Nathaniel L.; Schonbrunn, Agnes

    2017-01-01

    Fluorescence-guided surgery is an emerging imaging technique that can enhance the ability of surgeons to detect tumors when compared with visual observation. To facilitate characterization, fluorescently labeled probes have been dual-labeled with a radionuclide to enable cross-validation with nuclear imaging. In this study, we selected the somatostatin receptor imaging agent DOTATOC as the foundation for developing a dual-labeled analog. We hypothesized that a customized dual-labeling approach with a multimodality chelation (MMC) scaffold would minimize steric effects of dye conjugation and retain agonist properties. Methods: An MMC conjugate (MMC-TOC) was synthesized on solid-phase and compared with an analog prepared using conventional methods (DA-TOC). Both analogs were conjugated to IRDye 800 using copper-free click chemistry. The resulting compounds, MMC(IR800)-TOC and DA(IR800)-TOC, were labeled with Cu and 64Cu and tested in vitro in somatostatin receptor subtype 2–overexpressing HEK-293 cells to assess agonist properties, and in AR42J rat pancreatic cancer cells to determine receptor binding characteristics. Multimodality imaging was performed in AR42J xenografts. Results: Cu-MMC(IR800)-TOC demonstrated higher potency for cyclic adenosine monophosphate inhibition (half maximal effective concentration [EC50]: 0.21 ± 0.18 vs. 1.38 ± 0.54 nM) and receptor internalization (EC50: 41.9 ± 29.8 vs. 455 ± 299 nM) than Cu-DA(IR800)-TOC. Radioactive uptake studies showed that blocking with octreotide caused a dose-dependent reduction in 64Cu-MMC(IR800)-TOC uptake whereas 64Cu-DA(IR800)-TOC was not affected. In vivo studies revealed higher tumor uptake for 64Cu-MMC(IR800)-TOC than 64Cu-DA(IR800)-TOC (5.2 ± 0.2 vs. 3.6 ± 0.4 percentage injected dose per gram). In vivo blocking studies with octreotide reduced tumor uptake of 64Cu-MMC(IR800)-TOC by 66%. Excretion of 64Cu-MMC(IR800)-TOC was primarily through the liver and spleen whereas 64Cu-DA(IR800)-TOC was

  6. Modeling and dynamic properties of dual-chamber solid and liquid mixture vibration isolator

    NASA Astrophysics Data System (ADS)

    Li, F. S.; Chen, Q.; Zhou, J. H.

    2016-07-01

    The dual-chamber solid and liquid mixture (SALiM) vibration isolator, mainly proposed for vibration isolation of heavy machines with low frequency, consists of four principle parts: SALiM working media including elastic elements and incompressible oil, multi-layers bellows container, rigid reservoir and the oil tube connecting the two vessels. The isolation system under study is governed by a two-degrees-of-freedom (2-DOF) nonlinear equation including quadratic damping. Simplifying the nonlinear damping into viscous damping, the equivalent stiffness and damping model is derived from the equation for the response amplitude. Theoretical analysis and numerical simulation reveal that the isolator's stiffness and damping have multiple properties with different parameters, among which the effects of exciting frequency, vibrating amplitude, quadratic damping coefficient and equivalent stiffness of the two chambers on the isolator's dynamics are discussed in depth. Based on the boundary characteristics of stiffness and damping and the main causes for stiffness hardening effect, improvement strategies are proposed to obtain better dynamic properties. At last, experiments were implemented and the test results were generally consistent with the theoretical ones, which verified the reliability of the nonlinear dynamic model.

  7. Dual-ion-beam deposition of carbon films with diamond-like properties

    NASA Technical Reports Server (NTRS)

    Mirtich, M. J.; Swec, D. M.; Angus, J. C.

    1985-01-01

    A single and dual ion beam system was used to generate amorphous carbon films with diamond like properties. A methane/argon mixture at a molar ratio of 0.28 was ionized in the low pressure discharge chamber of a 30-cm-diameter ion source. A second ion source, 8 cm in diameter was used to direct a beam of 600 eV Argon ions on the substrates (fused silica or silicon) while the deposition from the 30-cm ion source was taking place. Nuclear reaction and combustion analysis indicate H/C ratios for the films to be 1.00. This high value of H/C, it is felt, allowed the films to have good transmittance. The films were impervious to reagents which dissolve graphitic and polymeric carbon structures. Although the measured density of the films was approximately 1.8 gm/cu cm, a value lower than diamond, the films exhibited other properties that were relatively close to diamond. These films were compared with diamond like films generated by sputtering a graphite target.

  8. Dual-Functional Ultrafiltration Membrane for Simultaneous Removal of Multiple Pollutants with High Performance.

    PubMed

    Pan, Shunlong; Li, Jiansheng; Noonan, Owen; Fang, Xiaofeng; Wan, Gaojie; Yu, Chengzhong; Wang, Lianjun

    2017-05-02

    Simultaneous removal of multiple pollutants from aqueous solution with less energy consumption is crucial in water purification. Here, a novel concept of dual-functional ultrafiltration (DFUF) membrane is demonstrated by entrapment of nanostructured adsorbents into the finger-like pores of ultrafiltration (UF) membrane rather than in the membrane matrix in previous reports of blend membranes, resulting in an exceptionally high active content and simultaneous removal of multiple pollutants from water due to the dual functions of rejection and adsorption. As a demonstration, hollow porous Zr(OH) x nanospheres (HPZNs) were immobilized in poly(ether sulfone) (PES) UF membranes through polydopamine coating with a high content of 68.9 wt %. The decontamination capacity of DFUF membranes toward multiple model pollutants (colloidal gold, polyethylene glycol (PEG), Pb(II)) was evaluated against a blend membrane. Compared to the blend membrane, the DFUF membranes showed 2.1-fold increase in the effective treatment volume for the treatment of Pb(II) contaminated water from 100 ppb to below 10 ppb (WHO drinking water standard). Simultaneously, the DFUF membranes effectively removed the colloidal gold and PEG below instrument detection limit, however the blend membrane only achieved 97.6% and 96.8% rejection for colloidal gold and PEG, respectively. Moreover, the DFUF membranes showed negligible leakage of nanoadsorbents during testing; and the membrane can be easily regenerated and reused. This study sheds new light on the design of high performance multifunction membranes for drinking water purification.

  9. Hybrid ultrasound and dual-wavelength optoacoustic biomicroscopy for functional neuroimaging

    NASA Astrophysics Data System (ADS)

    Rebling, Johannes; Estrada, Hector; Zwack, Michael; Sela, Gali; Gottschalk, Sven; Razansky, Daniel

    2017-03-01

    Many neurological disorders are linked to abnormal activation or pathological alterations of the vasculature in the affected brain region. Obtaining simultaneous morphological and physiological information of neurovasculature is very challenging due to the acoustic distortions and intense light scattering by the skull and brain. In addition, the size of cerebral vasculature in murine brains spans an extended range from just a few microns up to about a millimeter, all to be recorded in 3D and over an area of several dozens of mm2. Numerous imaging techniques exist that excel at characterizing certain aspects of this complex network but are only capable of providing information on a limited spatiotemporal scale. We present a hybrid ultrasound and dual-wavelength optoacoustic microscope, capable of rapid imaging of murine neurovasculature in-vivo, with high spatial resolution down to 12 μm over a large field of view exceeding 50mm2. The dual wavelength imaging capability allows for the visualization of functional blood parameters through an intact skull while pulse-echo ultrasound biomicroscopy images are captured simultaneously by the same scan head. The flexible hybrid design in combination with fast high-resolution imaging in 3D holds promise for generating better insights into the architecture and function of the neurovascular system.

  10. Dual function seal: visualized digital signature for electronic medical record systems.

    PubMed

    Yu, Yao-Chang; Hou, Ting-Wei; Chiang, Tzu-Chiang

    2012-10-01

    Digital signature is an important cryptography technology to be used to provide integrity and non-repudiation in electronic medical record systems (EMRS) and it is required by law. However, digital signatures normally appear in forms unrecognizable to medical staff, this may reduce the trust from medical staff that is used to the handwritten signatures or seals. Therefore, in this paper we propose a dual function seal to extend user trust from a traditional seal to a digital signature. The proposed dual function seal is a prototype that combines the traditional seal and digital seal. With this prototype, medical personnel are not just can put a seal on paper but also generate a visualized digital signature for electronic medical records. Medical Personnel can then look at the visualized digital signature and directly know which medical personnel generated it, just like with a traditional seal. Discrete wavelet transform (DWT) is used as an image processing method to generate a visualized digital signature, and the peak signal to noise ratio (PSNR) is calculated to verify that distortions of all converted images are beyond human recognition, and the results of our converted images are from 70 dB to 80 dB. The signature recoverability is also tested in this proposed paper to ensure that the visualized digital signature is verifiable. A simulated EMRS is implemented to show how the visualized digital signature can be integrity into EMRS.

  11. A dual change model of life satisfaction and functioning for individuals with schizophrenia

    PubMed Central

    Edmondson, Melissa; Pahwa, Rohini; Lee, Karen Kyeunghae; Hoe, Maanse; Brekke, John S.

    2013-01-01

    Despite the notion that increases in functioning should be associated with increases in life satisfaction in schizophrenia, research has often found no association between the two. Dual change models of global and domain-specific life satisfaction and functioning were examined in 145 individuals with schizophrenia receiving community-based services over 12 months. Functioning and satisfaction were measured using the Role Functioning Scale and Satisfaction with Life Scale. Data were analyzed using latent growth curve modeling. Improvement in global life satisfaction was associated with improvement in overall functioning over time. Satisfaction with living situation also improved as independent functioning improved. Work satisfaction did not improve as work functioning improved. Although social functioning improved, satisfaction with social relationships did not. The link between overall functioning and global life satisfaction provides support for a recovery-based orientation to community based psychosocial rehabilitation services. When examining sub-domains, the link between outcomes and subjective experience suggests a more complex picture than previously found. These findings are crucial to interventions and programs aimed at improving functioning and the subjective experiences of consumers recovering from mental illness. Interventions that show improvements in functional outcomes can assume that they will show concurrent improvements in global life satisfaction as well and in satisfaction with independent living. Interventions geared toward improving social functioning will need to consider the complexity of social relationships and how they affect satisfaction associated with personal relationships. Interventions geared towards improving work functioning will need to consider how the quality and level of work affect satisfaction with employment. PMID:22591780

  12. A dual physiological character for sexual function: libido and sexual pheromones.

    PubMed

    Motofei, Ion G

    2009-12-01

    Human sexual response is a complex function involving many cerebral, spinal and peripheral aspects; the last are relatively known and benefit from good pharmacological control, as in the case of erectile dysfunction. Spinal cord sexual reflexes also have a good theoretical and experimental description. There is minimal understanding of the cerebral sexual processes (libido, sexual arousal, orgasm). The initial perspective was that the cerebral areas implied in sexuality exert descending stimulatory and inhibitory influences on spinal cord sexual centres/reflexes. This was a wrong supposition, which inhibited progress in this subject, with a considerable impact on a subject's individual and social life. A new approach to sexual function arises from the idea that simple neurological structures can support only simple functions, while a more complex function requires correspondingly complex anatomical structures. For this reason the spinal cord would not be able to realise the integration of multiple (spinal and psychosensorial) stimuli into a unique and coherent ejaculation response. Consequently, all mechanisms implied in human sexuality would be cerebral processes, ejaculation reflexes ascending in evolution to the cerebral level. This new evolutionary concept was developed after 2001 in five distinct articles on the cerebral duality of sexual arousal, sexual hormones, ejaculation and serotonergic receptors. During this period other published results suggested a possible cerebral duality for sexual pheromones and libido in humans. All these dual physiological aspects are integrated in this review into one neurophysiological model, thus trying to further develop the new concepts of sexual function and perhaps relational behaviour. In conclusion, ejaculation is a dual cerebral process with arousal sensation (hormonally modulated) and libido perception (pheromonally modulated) as the afferent part. Two neurophysiological axes could exist in both men and women. In this

  13. Confirmation of translatability and functionality certifies the dual endothelin1/VEGFsp receptor (DEspR) protein.

    PubMed

    Herrera, Victoria L M; Steffen, Martin; Moran, Ann Marie; Tan, Glaiza A; Pasion, Khristine A; Rivera, Keith; Pappin, Darryl J; Ruiz-Opazo, Nelson

    2016-06-14

    In contrast to rat and mouse databases, the NCBI gene database lists the human dual-endothelin1/VEGFsp receptor (DEspR, formerly Dear) as a unitary transcribed pseudogene due to a stop [TGA]-codon at codon#14 in automated DNA and RNA sequences. However, re-analysis is needed given prior single gene studies detected a tryptophan [TGG]-codon#14 by manual Sanger sequencing, demonstrated DEspR translatability and functionality, and since the demonstration of actual non-translatability through expression studies, the standard-of-excellence for pseudogene designation, has not been performed. Re-analysis must meet UNIPROT criteria for demonstration of a protein's existence at the highest (protein) level, which a priori, would override DNA- or RNA-based deductions. To dissect the nucleotide sequence discrepancy, we performed Maxam-Gilbert sequencing and reviewed 727 RNA-seq entries. To comply with the highest level multiple UNIPROT criteria for determining DEspR's existence, we performed various experiments using multiple anti-DEspR monoclonal antibodies (mAbs) targeting distinct DEspR epitopes with one spanning the contested tryptophan [TGG]-codon#14, assessing: (a) DEspR protein expression, (b) predicted full-length protein size, (c) sequence-predicted protein-specific properties beyond codon#14: receptor glycosylation and internalization, (d) protein-partner interactions, and (e) DEspR functionality via DEspR-inhibition effects. Maxam-Gilbert sequencing and some RNA-seq entries demonstrate two guanines, hence a tryptophan [TGG]-codon#14 within a compression site spanning an error-prone compression sequence motif. Western blot analysis using anti-DEspR mAbs targeting distinct DEspR epitopes detect the identical glycosylated 17.5 kDa pull-down protein. Decrease in DEspR-protein size after PNGase-F digest demonstrates post-translational glycosylation, concordant with the consensus-glycosylation site beyond codon#14. Like other small single-transmembrane proteins, mass

  14. Upper-Extremity Dual-Task Function: An Innovative Method to Assess Cognitive Impairment in Older Adults

    PubMed Central

    Toosizadeh, Nima; Najafi, Bijan; Reiman, Eric M.; Mager, Reine M.; Veldhuizen, Jaimeson K.; O’Connor, Kathy; Zamrini, Edward; Mohler, Jane

    2016-01-01

    Background: Difficulties in orchestrating simultaneous tasks (i.e., dual-tasking) have been associated with cognitive impairments in older adults. Gait tests have been commonly used as the motor task component for dual-task assessments; however, many older adults have mobility impairments or there is a lack of space in busy clinical settings. We assessed an upper-extremity function (UEF) test as an alternative motor task to study the dual-task motor performance in older adults. Methods: Older adults (≥65 years) were recruited, and cognitive ability was measured using the Montreal cognitive assessment (MoCA). Participants performed repetitive elbow flexion with their maximum pace, once single-task, and once while counting backward by one (dual-task). Single- and dual-task gait tests were also performed with normal speed. Three-dimensional kinematics was measured both from upper-extremity and lower-extremity using wearable sensors to determine UEF and gait parameters. Parameters were compared between the cognitively impaired and healthy groups using analysis of variance tests, while controlling for age, gender, and body mass index (BMI). Correlations between UEF and gait parameters for dual-task and dual-task cost were assessed using linear regression models. Results: Sixty-seven older adults were recruited (age = 83 ± 10 years). Based on MoCA, 10 (15%) were cognitively impaired. While no significant differences were observed in the single-task condition, within the dual-task condition, the cognitively impaired group showed significantly less arm flexion speed (62%, d = 1.51, p = 0.02) and range of motion (27%, d = 0.93, p = 0.04), and higher speed variability (88%, d = 1.82, p < 0.0001) compared to the cognitively intact group, when adjusted with age, gender, and BMI. Significant correlations were observed between UEF speed parameters and gait stride velocity for dual-task condition (r = 0.55, p < 0.0001) and dual-task cost (r = 0.28, p = 0.03). Conclusion: We

  15. Upper-Extremity Dual-Task Function: An Innovative Method to Assess Cognitive Impairment in Older Adults.

    PubMed

    Toosizadeh, Nima; Najafi, Bijan; Reiman, Eric M; Mager, Reine M; Veldhuizen, Jaimeson K; O'Connor, Kathy; Zamrini, Edward; Mohler, Jane

    2016-01-01

    Difficulties in orchestrating simultaneous tasks (i.e., dual-tasking) have been associated with cognitive impairments in older adults. Gait tests have been commonly used as the motor task component for dual-task assessments; however, many older adults have mobility impairments or there is a lack of space in busy clinical settings. We assessed an upper-extremity function (UEF) test as an alternative motor task to study the dual-task motor performance in older adults. Older adults (≥65 years) were recruited, and cognitive ability was measured using the Montreal cognitive assessment (MoCA). Participants performed repetitive elbow flexion with their maximum pace, once single-task, and once while counting backward by one (dual-task). Single- and dual-task gait tests were also performed with normal speed. Three-dimensional kinematics was measured both from upper-extremity and lower-extremity using wearable sensors to determine UEF and gait parameters. Parameters were compared between the cognitively impaired and healthy groups using analysis of variance tests, while controlling for age, gender, and body mass index (BMI). Correlations between UEF and gait parameters for dual-task and dual-task cost were assessed using linear regression models. Sixty-seven older adults were recruited (age = 83 ± 10 years). Based on MoCA, 10 (15%) were cognitively impaired. While no significant differences were observed in the single-task condition, within the dual-task condition, the cognitively impaired group showed significantly less arm flexion speed (62%, d = 1.51, p = 0.02) and range of motion (27%, d = 0.93, p = 0.04), and higher speed variability (88%, d = 1.82, p < 0.0001) compared to the cognitively intact group, when adjusted with age, gender, and BMI. Significant correlations were observed between UEF speed parameters and gait stride velocity for dual-task condition (r = 0.55, p < 0.0001) and dual-task cost (r = 0.28, p = 0.03). We introduced a novel test for assessing dual

  16. Cellulose nanocrystals: synthesis, functional properties, and applications

    PubMed Central

    George, Johnsy; Sabapathi, SN

    2015-01-01

    Cellulose nanocrystals are unique nanomaterials derived from the most abundant and almost inexhaustible natural polymer, cellulose. These nanomaterials have received significant interest due to their mechanical, optical, chemical, and rheological properties. Cellulose nanocrystals primarily obtained from naturally occurring cellulose fibers are biodegradable and renewable in nature and hence they serve as a sustainable and environmentally friendly material for most applications. These nanocrystals are basically hydrophilic in nature; however, they can be surface functionalized to meet various challenging requirements, such as the development of high-performance nanocomposites, using hydrophobic polymer matrices. Considering the ever-increasing interdisciplinary research being carried out on cellulose nanocrystals, this review aims to collate the knowledge available about the sources, chemical structure, and physical and chemical isolation procedures, as well as describes the mechanical, optical, and rheological properties, of cellulose nanocrystals. Innovative applications in diverse fields such as biomedical engineering, material sciences, electronics, catalysis, etc, wherein these cellulose nanocrystals can be used, are highlighted. PMID:26604715

  17. Dual-task training effects on motor and cognitive functional abilities in individuals with stroke: a systematic review.

    PubMed

    He, Ying; Yang, Lei; Zhou, Jing; Yao, Liqing; Pang, Marco Yiu Chung

    2018-02-01

    This systematic review aimed to examine the effects of dual-task balance and mobility training in people with stroke. An extensive electronic databases literature search was conducted using MEDLINE, PubMed, EBSCO, The Cochrane Library, Web of Science, SCOPUS, and Wiley Online Library. Randomized controlled studies that assessed the effects of dual-task training in stroke patients were included for the review (last search in December 2017). The methodological quality was evaluated using the Cochrane Collaboration recommendation, and level of evidence was determined according to the criteria described by the Oxford Center for Evidence-Based Medicine. About 13 articles involving 457 participants were included in this systematic review. All had substantial risk of bias and thus provided level IIb evidence only. Dual-task mobility training was found to induce more improvement in single-task walking function (standardized effect size = 0.14-2.24), when compared with single-task mobility training. Its effect on dual-task walking function was not consistent. Cognitive-motor balance training was effective in improving single-task balance function (standardized effect size = 0.27-1.82), but its effect on dual-task balance ability was not studied. The beneficial effect of dual-task training on cognitive function was provided by one study only and thus inconclusive. There is some evidence that dual-task training can improve single-task walking and balance function in individuals with stroke. However, any firm recommendation cannot be made due to the weak methodology of the studies reviewed.

  18. MO detector (MOD): a dual-function optical modulator-detector for on-chip communication

    NASA Astrophysics Data System (ADS)

    Sun, Shuai; Zhang, Ruoyu; Peng, Jiaxin; Narayana, Vikram K.; Dalir, Hamed; El-Ghazawi, Tarek; Sorger, Volker J.

    2018-04-01

    Physical challenges at the device and interconnect level limit both network and computing energy efficiency. While photonics is being considered to address interconnect bottlenecks, optical routing is still limited by electronic circuitry, requiring substantial overhead for optical-electrical-optical conversion. Here we show a novel design of an integrated broadband photonic-plasmonic hybrid device termed MODetector featuring dual light modulation and detection function to act as an optical transceiver in the photonic network-on-chip. With over 10 dB extinction ratio and 0.8 dB insertion loss at the modulation state, this MODetector provides 0.7 W/A responsivity in the detection state with 36 ps response time. This multi-functional device: (i) eliminates OEO conversion, (ii) reduces optical losses from photodetectors when not needed, and (iii) enables cognitive routing strategies for network-on-chips.

  19. Carbodithioic acid esters of fluoxetine, a novel class of dual-function spermicides.

    PubMed

    Kiran Kumar, S T V S; Kumar, Lalit; Sharma, Vishnu L; Jain, Ashish; Jain, Rajeev K; Maikhuri, Jagdamba P; Kumar, Manish; Shukla, Praveen K; Gupta, Gopal

    2008-10-01

    Carbodithioic acid esters of fluoxetine have been prepared by replacing the methylamino function in aminopropane chain with carbodithioic acid ester group and by adding various S-2-hydroxypropyl ester of dialkyl carbodithioic acid at 3-methylamino group. Some of these compounds showed spermicidal, antifungal and anti-Trichomonas activities. The study revealed that incorporation of carbodithioic acid residue directly into fluoxetine structure leads to compounds with better antifungal and anti-Trichomonas activities, and N-methyl-[3-phenyl-3-(4-trifluoromethyl-phenoxy)-propyl]carbodithioic acid S-(2-pyrrolidino-ethyl) ester (14) has shown better profile than both fluoxetine and nonoxynol-9. Further lead optimization may yield a potent dual-function spermicide.

  20. Highly efficient SO2 capture by dual functionalized ionic liquids through a combination of chemical and physical absorption.

    PubMed

    Cui, Guokai; Wang, Congmin; Zheng, Junjie; Guo, Yan; Luo, Xiaoyan; Li, Haoran

    2012-03-07

    Two kinds of dual functionalized ionic liquids with ether-functionalized cations and tetrazolate anions were designed, prepared, and used for SO(2) capture, which exhibit an extremely high SO(2) capacity and excellent reversibility through a combination of chemical and physical absorption. This journal is © The Royal Society of Chemistry 2012

  1. GrDHP: a general utility function representation for dual heuristic dynamic programming.

    PubMed

    Ni, Zhen; He, Haibo; Zhao, Dongbin; Xu, Xin; Prokhorov, Danil V

    2015-03-01

    A general utility function representation is proposed to provide the required derivable and adjustable utility function for the dual heuristic dynamic programming (DHP) design. Goal representation DHP (GrDHP) is presented with a goal network being on top of the traditional DHP design. This goal network provides a general mapping between the system states and the derivatives of the utility function. With this proposed architecture, we can obtain the required derivatives of the utility function directly from the goal network. In addition, instead of a fixed predefined utility function in literature, we conduct an online learning process for the goal network so that the derivatives of the utility function can be adaptively tuned over time. We provide the control performance of both the proposed GrDHP and the traditional DHP approaches under the same environment and parameter settings. The statistical simulation results and the snapshot of the system variables are presented to demonstrate the improved learning and controlling performance. We also apply both approaches to a power system example to further demonstrate the control capabilities of the GrDHP approach.

  2. Dual-task performance involving hand dexterity and cognitive tasks and daily functioning in people with schizophrenia: a pilot study.

    PubMed

    Lin, Keh-chung; Wu, Yi-fang; Chen, I-chen; Tsai, Pei-luen; Wu, Ching-yi; Chen, Chia-ling

    2015-01-01

    This study investigated separate and concurrent performance on cognitive and hand dexterity tasks and the relationship to daily functioning in 16 people with schizophrenia and 16 healthy control participants. Participants performed the Purdue Pegboard Test and the Serial Seven Subtraction Test under single- and dual-task conditions and completed two daily functioning evaluations. The hand dexterity of all participants declined in the dual-task condition, but the discrepancy between single-task and dual-task hand dexterity was greater in the schizophrenia group than in the control group (p<.03, d>.70, for all). The extent of discrepancy in hand dexterity was negatively correlated with daily functioning in the schizophrenia group (rs=-.3 to -.5, ps=.04-.26). Ability to perform dual tasks may be an indicator of daily functioning in people with schizophrenia. Use of dual-task training may be considered as a therapeutic activity with these clients. Copyright © 2015 by the American Occupational Therapy Association, Inc.

  3. Preparation of a novel dual-function strong cation exchange/hydrophobic interaction chromatography stationary phase for protein separation.

    PubMed

    Zhao, Kailou; Yang, Li; Wang, Xuejiao; Bai, Quan; Yang, Fan; Wang, Fei

    2012-08-30

    We have explored a novel dual-function stationary phase which combines both strong cation exchange (SCX) and hydrophobic interaction chromatography (HIC) characteristics. The novel dual-function stationary phase is based on porous and spherical silica gel functionalized with ligand containing sulfonic and benzyl groups capable of electrostatic and hydrophobic interaction functionalities, which displays HIC character in a high salt concentration, and IEC character in a low salt concentration in mobile phase employed. As a result, it can be employed to separate proteins with SCX and HIC modes, respectively. The resolution and selectivity of the dual-function stationary phase were evaluated under both HIC and SCX modes with standard proteins and can be comparable to that of conventional IEC and HIC columns. More than 96% of mass and bioactivity recoveries of proteins can be achieved in both HIC and SCX modes, respectively. The results indicated that the novel dual-function column could replace two individual SCX and HIC columns for protein separation. Mixed retention mechanism of proteins on this dual-function column based on stoichiometric displacement theory (SDT) in LC was investigated to find the optimal balance of the magnitude of electrostatic and hydrophobic interactions between protein and the ligand on the silica surface in order to obtain high resolution and selectivity for protein separation. In addition, the effects of the hydrophobicity of the ligand of the dual-function packings and pH of the mobile phase used on protein separation were also investigated in detail. The results show that the ligand with suitable hydrophobicity to match the electrostatic interaction is very important to prepare the dual-function stationary phase, and a better resolution and selectivity can be obtained at pH 6.5 in SCX mode. Therefore, the dual-function column can replace two individual SCX and HIC columns for protein separation and be used to set up two-dimensional liquid

  4. Dual-Functional Polyethylene Glycol-b-polyhexanide Surface Coating with in Vitro and in Vivo Antimicrobial and Antifouling Activities.

    PubMed

    Zhi, Zelun; Su, Yajuan; Xi, Yuewei; Tian, Liang; Xu, Miao; Wang, Qianqian; Padidan, Sara; Li, Peng; Huang, Wei

    2017-03-29

    In recent years, microbial colonization on the surface of biomedical implants/devices has become a severe threat to human health. Herein, surface-immobilized guanidine derivative block copolymers create an antimicrobial and antifouling dual-functional coating. We report the preparation of an antimicrobial and antifouling block copolymer by the conjugation of polyhexanide (PHMB) with either allyl glycidyl ether or allyloxy polyethylene glycol (APEG; MW 1200 and 2400). The allyl glycidyl ether modified PHMB (A-PHMB) and allyloxy polyethylene glycol 1200/2400 modified PHMB (APEG 1200/2400 -PHMB) copolymers were grafted onto a silicone rubber surface as a bottlebrush-like coating, respectively, using a plasma-UV-assisted surface-initiated polymerization. Both A-PHMB and APEG 1200/2400 -PHMB coatings exhibited excellent broad-spectrum antimicrobial properties against Gram-negative/positive bacteria and fungi. The APEG 2400 -PHMB coating displayed an improved antibiofilm as well as antifouling properties and a long reusable cycle, compared with two other coatings, due to its abundant PEG blocks among those copolymers. Also, the APEG 2400 -PHMB-coated silicone coupons were biocompatible toward mammalian cells, as revealed by in vitro hemocompatibile and cytotoxic assays. An in vivo study showed a significant decline of Escherichia coli colonies with a 5-log reduction, indicating the APEG 2400 -PHMB coating surface worked effectively in the rodent subcutaneous infection model. This PHMB-based block copolymer coating is believed to be an effective strategy to prevent biomaterial-associated infections.

  5. Dual-Level Method for Estimating Multistructural Partition Functions with Torsional Anharmonicity.

    PubMed

    Bao, Junwei Lucas; Xing, Lili; Truhlar, Donald G

    2017-06-13

    For molecules with multiple torsions, an accurate evaluation of the molecular partition function requires consideration of multiple structures and their torsional-potential anharmonicity. We previously developed a method called MS-T for this problem, and it requires an exhaustive conformational search with frequency calculations for all the distinguishable conformers; this can become expensive for molecules with a large number of torsions (and hence a large number of structures) if it is carried out with high-level methods. In the present work, we propose a cost-effective method to approximate the MS-T partition function when there are a large number of structures, and we test it on a transition state that has eight torsions. This new method is a dual-level method that combines an exhaustive conformer search carried out by a low-level electronic structure method (for instance, AM1, which is very inexpensive) and selected calculations with a higher-level electronic structure method (for example, density functional theory with a functional that is suitable for conformational analysis and thermochemistry). To provide a severe test of the new method, we consider a transition state structure that has 8 torsional degrees of freedom; this transition state structure is formed along one of the reaction pathways of the hydrogen abstraction reaction (at carbon-1) of ketohydroperoxide (KHP; its IUPAC name is 4-hydroperoxy-2-pentanone) by OH radical. We find that our proposed dual-level method is able to significantly reduce the computational cost for computing MS-T partition functions for this test case with a large number of torsions and with a large number of conformers because we carry out high-level calculations for only a fraction of the distinguishable conformers found by the low-level method. In the example studied here, the dual-level method with 40 high-level optimizations (1.8% of the number of optimizations in a coarse-grained full search and 0.13% of the number of

  6. Interhemispheric modulation of dual-mode, noninvasive brain stimulation on motor function.

    PubMed

    Park, Eunhee; Kim, Yun-Hee; Chang, Won Hyuk; Kwon, Tae Gun; Shin, Yong-Il

    2014-06-01

    To investigate the effects of simultaneous, bihemispheric, dual-mode stimulation using repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) on motor functions and cortical excitability in healthy individuals. Twenty-five healthy, right-handed volunteers (10 men, 15 women; mean age, 25.5 years) were enrolled. All participants received four randomly arranged, dual-mode, simultaneous stimulations under the following conditions: condition 1, high-frequency rTMS over the right primary motor cortex (M1) and sham tDCS over the left M1; condition 2, high-frequency rTMS over the right M1 and anodal tDCS over the left M1; condition 3, high-frequency rTMS over the right M1 and cathodal tDCS over the left M1; and condition 4, sham rTMS and sham tDCS. The cortical excitability of the right M1 and motor functions of the left hand were assessed before and after each simulation. Motor evoked potential (MEP) amplitudes after stimulation were significantly higher than before stimulation, under the conditions 1 and 2. The MEP amplitude in condition 2 was higher than both conditions 3 and 4, while the MEP amplitude in condition 1 was higher than condition 4. The results of the Purdue Pegboard test and the box and block test showed significant improvement in conditions 1 and 2 after stimulation. Simultaneous stimulation by anodal tDCS over the left M1 with high-frequency rTMS over the right M1 could produce interhemispheric modulation and homeostatic plasticity, which resulted in modulation of cortical excitability and motor functions.

  7. Functional outcome of Schatzker type V and VI tibial plateau fractures treated with dual plates

    PubMed Central

    Prasad, G Thiruvengita; Kumar, T Suresh; Kumar, R Krishna; Murthy, Ganapathy K; Sundaram, Nandkumar

    2013-01-01

    Background: Dual plate fixation in comminuted bicondylar tibial plateau fractures remains controversial. Open reduction and internal fixation, specifically through compromised soft tissues, has historically been associated with major wound complications. Alternate methods of treatment have been described, each with its own merits and demerits. We performed a retrospective study to evaluate the functional outcome of lateral and medial plate fixation of Schatzker type V and VI fractures through an anterolateral approach, and a medial minimally invasive approach or a posteromedial approach. Materials and Methods: We treated 46 tibial plateau fractures Schatzker type V and VI with lateral and medial plates through an anterolateral approach and a medial minimal invasive approach over an 8 years period. Six patients were lost to followup. Radiographs in two planes were taken in all cases. Immediate postoperative radiographs were assessed for quality of reduction and fixation. The functional outcome was evaluated according to the Oxford Knee Score criteria on followup. Results: Forty patients (33 men and 7 women) who completed the followup were included in the study. There were 20 Schatzker type V fractures and 20 Schatzker type VI fractures. The mean duration of followup was 4 years (range 1-8 years). All patients had a satisfactory articular reduction defined as ≤2 mm step-off or gap as assessed on followup. All patients had a good coronal and sagittal plane alignment, and articular width as assessed on supine X-rays of the knee in the anteroposterior (AP) and lateral views. The functional outcome, as assessed by the Oxford Knee Score, was excellent in 30 patients and good in 10 patients. All patients returned to their pre-injury level of activity and employment. There were no instances of deep infection. Conclusions: Dual plate fixation of severe bicondylar tibial plateau fractures is an excellent treatment option as it provides rigid fixation and allows early knee

  8. Dual-functionalized graphene oxide for enhanced siRNA delivery to breast cancer cells.

    PubMed

    Imani, Rana; Shao, Wei; Taherkhani, Samira; Emami, Shahriar Hojjati; Prakash, Satya; Faghihi, Shahab

    2016-11-01

    The aim of this study is to improve hydrocolloid stability and siRNA transfection ability of a reduced graphene oxide (rGO) based nano-carrier using a phospholipid-based amphiphilic polymer (PL-PEG) and cell penetrating peptide (CPPs). The dual functionalized nano-carrier is comprehensively characterized for its chemical structure, size, surface charge and morphology as well as thermal stability. The nano-carrier cytocompatibility, siRNA condensation ability both in the presence and absence of enzyme, endosomal buffering capacity, cellular uptake and intracellular localization are also assessed. The siRNA loaded nano-carrier is used for internalization to MCF-7 cells and its gene silencing ability is compared with AllStars Hs Cell Death siRNA as a model gene. The nano-carrier remains stable in biological solution, exhibits excellent cytocompatibility, retards the siRNA migration and protects it against enzyme degradation. The buffering capacity analysis shows that incorporation of the peptide in nano-carrier structure would increase the resistance to endo/lysosomal like acidic condition (pH 6-4) The functionalized nano-carrier which is loaded with siRNA in an optimal N:P ratio presents superior internalization efficiency (82±5.1% compared to HiPerFect(®)), endosomal escape quality and capable of inducing cell death in MCF-7 cancer cells (51±3.1% compared to non-treated cells). The success of siRNA-based therapy is largely dependent on the safe and efficient delivery system, therefore; the dual functionalized rGO introduced here could have a great potential to be used as a carrier for siRNA delivery with relevancy in therapeutics and clinical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Synthesis of iboga-like isoquinuclidines: Dual opioid receptors agonists having antinociceptive properties.

    PubMed

    Banerjee, Tuhin Suvro; Paul, Sibasish; Sinha, Surajit; Das, Sumantra

    2014-11-01

    Some novel iboga-analogues consisting of benzofuran moiety and dehydroisoquinuclidine ring connected by -CH2-, (CH2)2 and (CH2)3 linkers have been synthesized with the view to develop potential antinociceptive drugs. The compounds 14 and 21 showed binding at the μ-opioid receptor (MOR), while the compound 11a exhibited dual affinities at both MOR and κ-opioid receptor (KOR). MAP kinase activation indicated all three compounds have opioid agonistic properties. The presence of a double bond and endo-methylcarboxylate group in the dehydroisoquinuclidine ring and the benzofuran and methylene spacer appeared to be essential for opioid receptor binding. Further studies demonstrated 11a caused significant antinociception in mice in the hot-plate test which was comparable to that produced by morphine. The compound 11a was also found to be nontremorigenic unlike various iboga congeners. This study identifies a new pharmacophore which may lead to the development of suitable substitute of morphine in the treatment of pain. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Thermoelectric properties of Tl and I dual-doped Bi2Te3-based alloys

    NASA Astrophysics Data System (ADS)

    Wu, Fang; He, Qinglin; Tang, Mingsheng; Song, Hongzhang

    2018-04-01

    TlxBi2‑xTe3‑xIx (x = 0, 0.05, 0.1 and 0.2) flower-like nanopowders were prepared successfully by the hydrothermal method. Then, the synthesized nanoparticles were pressed into bulks by hot-pressing. The thermoelectric (TE) properties of the TlxBi2‑xTe3‑xIx bulk samples were investigated and discussed. The results showed that the influences of Tl doping on the electrical resistivity and Seebeck coefficients of the Bi2Te3 is over that of I doping. Thus, the power factors of the dual-doped bulks are all less than that of the Bi2Te3 bulk. The thermal conductivities of the TlxBi2‑xTe3‑xIx bulk samples also remain at lower values. As a result, the ZT value of the optimized doped bulk Tl0.1Bi1.9Te2.9I0.1 attains a value of 1.1 at 398 K.

  11. Accelerating image reconstruction in dual-head PET system by GPU and symmetry properties.

    PubMed

    Chou, Cheng-Ying; Dong, Yun; Hung, Yukai; Kao, Yu-Jiun; Wang, Weichung; Kao, Chien-Min; Chen, Chin-Tu

    2012-01-01

    Positron emission tomography (PET) is an important imaging modality in both clinical usage and research studies. We have developed a compact high-sensitivity PET system that consisted of two large-area panel PET detector heads, which produce more than 224 million lines of response and thus request dramatic computational demands. In this work, we employed a state-of-the-art graphics processing unit (GPU), NVIDIA Tesla C2070, to yield an efficient reconstruction process. Our approaches ingeniously integrate the distinguished features of the symmetry properties of the imaging system and GPU architectures, including block/warp/thread assignments and effective memory usage, to accelerate the computations for ordered subset expectation maximization (OSEM) image reconstruction. The OSEM reconstruction algorithms were implemented employing both CPU-based and GPU-based codes, and their computational performance was quantitatively analyzed and compared. The results showed that the GPU-accelerated scheme can drastically reduce the reconstruction time and thus can largely expand the applicability of the dual-head PET system.

  12. Properties and characteristics of dual-modified rice starch based biodegradable films.

    PubMed

    Woggum, Thewika; Sirivongpaisal, Piyarat; Wittaya, Thawien

    2014-06-01

    In this study, the dual-modified rice starch was hydroxypropylated with 6-12% of propylene oxide followed by crosslinking with 2% sodium trimetaphosphate (STMP) and a mixture of 2% STMP and 5% sodium tripolyphosphate (STPP). Increasing the propylene oxide concentrations in the DMRS yielded an increase in the molar substitution (MS) and degree of substitution (DS). However, the gelatinization parameters, paste properties, gel strength and paste clarity showed an inverse trend. The biodegradable films from the DMRS showed an increase the tensile strength, elongation at break and film solubility, while the transparency value decreased when the concentration of propylene oxide increased. However the water vapor permeability of the films did not significantly change with an increase in the concentration of propylene oxide. In addition, it was found that DMRS films crosslinked with 2% STMP demonstrated higher tensile strength, transparency value and lower water vapor permeability than the DMRS films crosslinked with a mixture of 2% STMP and 5% STPP. The XRD analysis of the DMRS films showed a decrease in crystallinity when the propylene oxide concentrations increased and the crystallinity of DMRS films with 2% STMP were higher than the DMRS films with a mixture of 2% STMP and 5% STPP. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Microstructure and Fatigue Properties of Laser Welded DP590 Dual-Phase Steel Joints

    NASA Astrophysics Data System (ADS)

    Xie, Chaojie; Yang, Shanglei; Liu, Haobo; Zhang, Qi; Cao, Yaming; Wang, Yuan

    2017-08-01

    In this paper, cold-rolled DP590 dual-phase steel sheets with 1.5 mm thickness were butt-welded by a fiber laser, and the evolution and effect on microhardness, tensile property and fatigue property of the welded joint microstructure were studied. The results showed that the base metal is composed of ferrite and martensite, with the martensite dispersed in the ferrite matrix in an island manner. The microstructure of the weld zone was lath-shaped martensite that can be refined further by increasing the welding speed, while the heat-affected zone was composed of ferrite and tempered martensite. The microhardness increased with increasing welding speed, and the hardness reached its highest value—393.8 HV—when the welding speed was 5 m/min. Static tensile fracture of the welded joints always occurred in the base metal, and the elongation at break was more than 16%. The conditional fatigue limits of the base metal and the weld joints were 354.2 and 233.6 MPa, respectively, under tension-tension fatigue tests with a stress rate of 0.1. After observation of the fatigue fracture morphology, it was evident that the fatigue crack of the base metal had sprouted into the surface pits and that its expansion would be accelerated under the action of a secondary crack. The fatigue source of the welded joint was generated in the weld zone and expanded along the martensite, forming a large number of fatigue striations. Transient breaking, which occurred in the heat-affected zone of the joint as a result of the formation of a large number of dimples, reflected the obvious characteristics of ductile fracture.

  14. Physical properties of self-, dual-, and light-cured direct core materials.

    PubMed

    Rüttermann, Stefan; Alberts, Ian; Raab, Wolfgang H M; Janda, Ralf R

    2011-08-01

    The objective of this study is to evaluate flexural strength, flexural modulus, compressive strength, curing temperature, curing depth, volumetric shrinkage, water sorption, and hygroscopic expansion of two self-, three dual-, and three light-curing resin-based core materials. Flexural strength and water sorption were measured according to ISO 4049, flexural modulus, compressive strength, curing temperature, and curing depth according to well-proven, literature-known methods, and the volumetric behavior was determined by the Archimedes' principle. ANOVA was calculated to find differences between the materials' properties, and correlation of water sorption and hygroscopic expansion was analysed according to Pearson (p < 0.05). Clearfil Photo Core demonstrated the highest flexural strength (125 ± 12 MPa) and curing depth (15.2 ± 0.1 mm) and had the highest flexural modulus (≈12.6 ± 1.2 GPa) concertedly with Multicore HB. The best compressive strength was measured for Voco Rebilda SC and Clearfil DC Core Auto (≈260 ± 10 MPa). Encore SuperCure Contrast had the lowest water sorption (11.8 ± 3.3 µg mm(-3)) and hygroscopic expansion (0.0 ± 0.2 vol.%). Clearfil Photo Core and Encore SuperCure Contrast demonstrated the lowest shrinkage (≈2.1 ± 0.1 vol.%). Water sorption and hygroscopic expansion had a very strong positive correlation. The investigated core materials significantly differed in the tested properties. The performance of the materials depended on their formulation, as well as on the respective curing process.

  15. One-Pot Fabrication of Antireflective/Antibacterial Dual-Function Ag NP-Containing Mesoporous Silica Thin Films.

    PubMed

    Wang, Kaikai; He, Junhui

    2018-04-04

    Thin films that integrate antireflective and antibacterial dual functions are not only scientifically interesting but also highly desired in many practical applications. Unfortunately, very few studies have been devoted to the preparation of thin films with both antireflective and antibacterial properties. In this study, mesoporous silica (MSiO 2 ) thin films with uniformly dispersed Ag nanoparticles (Ag NPs) were prepared through a one-pot process, which simultaneously shows high transmittance, excellent antibacterial activity, and mechanical robustness. The optimal thin-film-coated glass substrate demonstrates a maximum transmittance of 98.8% and an average transmittance of 97.1%, respectively, in the spectral range of 400-800 nm. The growth and multiplication of typical bacteria, Escherichia coli ( E. coli), were effectively inhibited on the coated glass. Pencil hardness test, tape adhesion test, and sponge washing test showed favorable mechanical robustness with 5H pencil hardness, 5A grade adhesion, and functional durability of the coating, which promises great potential for applications in various touch screens, windows for hygiene environments, and optical apparatuses for medical uses such as endoscope, and so on.

  16. Via fill properties of organic BARCs in dual-damascene application

    NASA Astrophysics Data System (ADS)

    Huang, Runhui

    2004-05-01

    With the introduction of copper as the interconnect metal, the Dual Damascene (DD) process has been integrated into integrated circuit (IC) device fabrication. The DD process utilizes organic bottom anti-reflective coatings (BARCs) not only to eliminate the thin film interference effects but also to act as via fill materials. However, three serious processing problems are encountered with organic BARCs. One is the formation of voids, which are trapped gas bubbles (evaporating solvent, byproduct of the curing reaction and air) inside the vias. Another problem is non-uniform BARC layer thickness in different via pitch areas. The third problem is the formation of fences during plasma etch. Fences are formed from materials that are removed by plasma and subsequently deposited on the sidewall surrounding the via openings during the etching process. Voids can cause variations in BARC top thickness, optical properties, via fill percentage, and plasma etch rate. This study focuses on the factors that influence the formation of voids and addresses the ways to eliminate them by optimizing the compositions of formulations and the processing conditions. Effects of molecular weight of the polymer, nature of the crosslinker, additives, and bake temperature were examined. The molecular weight of the polymer is one of the important factors that needs to be controlled carefully. Polymers with high molecular weights tend to trap voids inside the vias. Low molecular weight polymers have low Tg and low viscosity, which enables good thermal flow so that the BARC can fill vias easily without voids. Several kinds of crosslinkers were investigated in this study. When used with the same polymer system, formulations with different crosslinkers show varying results that affect planar fill, sidewall coverage, and, in some cases, voids. Additives also can change via fill behavior dramatically, and choosing the right additive will improve the via fill property. Processing conditions such as

  17. Dual role of betel leaf extract on thyroid function in male mice.

    PubMed

    Panda, S; Kar, A

    1998-12-01

    The effects of betel leaf extract (0.10, 0.40, 0.80 and 2.0 g kg-1 day-1 for 15 days) on the alterations in thyroid hormone concentrations. lipid peroxidation (LPO) and on the activities of superoxide dismutase (SOD) and catalase (CAT) were investigated in male Swiss mice. Administration of betel leaf extract exhibited a dual role, depending on the different doses. While the lowest dose decreased thyroxine (T4) and increased serum triiodothyronine (T3) concentrations, reverse effects were observed at two higher doses. Higher doses also increased LPO with a concomitant decrease in SOD and CAT activities. However, with the lowest dose most of these effects were reversed. These findings suggest that betel leaf can be both stimulatory and inhibitory to thyroid function, particularly for T3 generation and lipid peroxidation in male mice, depending on the amount consumed.

  18. Effects of Gait Self-Efficacy and Lower-Extremity Physical Function on Dual-Task Performance in Older Adults

    PubMed Central

    Banducci, Sarah E.; Daugherty, Ana M.; Fanning, Jason; Awick, Elizabeth A.; Porter, Gwenndolyn C.; Burzynska, Agnieszka; Shen, Sa; Kramer, Arthur F.; McAuley, Edward

    2017-01-01

    Objectives. Despite evidence of self-efficacy and physical function's influences on functional limitations in older adults, few studies have examined relationships in the context of complex, real-world tasks. The present study tested the roles of self-efficacy and physical function in predicting older adults' street-crossing performance in single- and dual-task simulations. Methods. Lower-extremity physical function, gait self-efficacy, and street-crossing success ratio were assessed in 195 older adults (60–79 years old) at baseline of a randomized exercise trial. During the street-crossing task, participants walked on a self-propelled treadmill in a virtual reality environment. Participants crossed the street without distraction (single-task trials) and conversed on a cell phone (dual-task trials). Structural equation modeling was used to test hypothesized associations independent of demographic and clinical covariates. Results. Street-crossing performance was better on single-task trials when compared with dual-task trials. Direct effects of self-efficacy and physical function on success ratio were observed in dual-task trials only. The total effect of self-efficacy was significant in both conditions. The indirect path through physical function was evident in the dual-task condition only. Conclusion. Physical function can predict older adults' performance on high fidelity simulations of complex, real-world tasks. Perceptions of function (i.e., self-efficacy) may play an even greater role. The trial is registered with United States National Institutes of Health ClinicalTrials.gov (ID: NCT01472744; Fit & Active Seniors Trial). PMID:28255557

  19. Onsite-effects of dual-hemisphere versus conventional single-hemisphere transcranial direct current stimulation: A functional MRI study.

    PubMed

    Kwon, Yong Hyun; Jang, Sung Ho

    2012-08-25

    We performed functional MRI examinations in six right-handed healthy subjects. During functional MRI scanning, transcranial direct current stimulation was delivered with the anode over the right primary sensorimotor cortex and the cathode over the left primary sensorimotor cortex using dual-hemispheric transcranial direct current stimulation. This was compared to a cathode over the left supraorbital area using conventional single-hemispheric transcranial direct current stimulation. Voxel counts and blood oxygenation level-dependent signal intensities in the right primary sensorimotor cortex regions were estimated and compared between the two transcranial direct current stimulation conditions. Our results showed that dual-hemispheric transcranial direct current stimulation induced greater cortical activities than single-hemispheric transcranial direct current stimulation. These findings suggest that dual-hemispheric transcranial direct current stimulation may provide more effective cortical stimulation than single-hemispheric transcranial direct current stimulation.

  20. [Functional properties and health benefits of lycopene].

    PubMed

    Cruz Bojórquez, Reyna María; González Gallego, Javier; Sánchez Collado, Pilar

    2013-01-01

    Lycopene is a carotenoid, which is found mainly in tomatoes, retains its functional properties after processing, is not toxic and has antioxidant, anti-inflammatory and chemotherapeutics effects in cardiovascular or neurodegenerative diseases and in some cancers. However, it seems that its intake through the diet is inadequate. The objective of this review is to highlight the properties of lycopene and provide recommendations to improve its health benefits. We performed a literature review related to the topic through Pub Med database. The WHO and national governments promote through food guides the daily consumption of 400 g of fruits and vegetables because of their contain in antioxidants including lycopene. Lycopene intake widely varies, with an average consumption between 5 and 7 mg/day. Controversy arises from the ranger of figures between different studies and the fact that there is no recommended amount, precluding comparisons of national and international level and the establishment of policies and strategies to ensure its consumption. Lycopene intake can be seen as a preventive measure and non pharmacological therapy for different types of diseases, but the work of professionals in nutrition and health is required to increase its intake through food education and to propose daily intakes from results of scientific research. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

  1. Dual Vacancies: An Effective Strategy Realizing Synergistic Optimization of Thermoelectric Property in BiCuSeO.

    PubMed

    Li, Zhou; Xiao, Chong; Fan, Shaojuan; Deng, Yu; Zhang, Wenshuai; Ye, Bangjiao; Xie, Yi

    2015-05-27

    Vacancy is a very important class of phonon scattering center to reduce thermal conductivity for the development of high efficient thermoelectric materials. However, conventional monovacancy may also act as an electron or hole acceptor, thereby modifying the electrical transport properties and even worsening the thermoelectric performance. This issue urges us to create new types of vacancies that scatter phonons effectively while not deteriorating the electrical transport. Herein, taking BiCuSeO as an example, we first reported the successful synergistic optimization of electrical and thermal parameters through Bi/Cu dual vacancies. As expected, as compared to its pristine and monovacancy samples, these dual vacancies further increase the phonon scattering, which results in an ultra low thermal conductivity of 0.37 W m(-1) K(-1) at 750 K. Most importantly, the clear-cut evidence in positron annihilation unambiguously confirms the interlayer charge transfer between these Bi/Cu dual vacancies, which results in the significant increase of electrical conductivity with relatively high Seebeck coefficient. As a result, BiCuSeO with Bi/Cu dual vacancies shows a high ZT value of 0.84 at 750 K, which is superior to that of its native sample and monovacancies-dominant counterparts. These findings undoubtedly elucidate a new strategy and direction for rational design of high performance thermoelectric materials.

  2. Functional properties of wasabi and horseradish.

    PubMed

    Kinae, N; Masuda, H; Shin, I S; Furugori, M; Shimoi, K

    2000-01-01

    Wasabi (Wasabi japonica) and horseradish (Cholearia arnoracia) are used as spices of daily foodstuffs. Allylisothiocyanate (AIT) is a potent component in both plants and occurs by grating them. It is well known that AIT shows inhibitory effect on the growth of food poisoning bacteria and fungi. In this work, several functional properties of roots and leaves from wasabi and horseradish were examined in vitro. Each sample showed peroxidase activity. They also exhibited antioxidative and superoxide scavenging potency. Antimutagenic activity was observed toward 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline [MeIQx], a well-known mutagen/carcinogen in broiled fish and meat. They also decreased His+ revertant colonies of 3-chloro-4-dichloromethyl-5-hydroxy-2(5H)-furanone (MX) in the Ames test, a strong mutagen and carcinogen in chlorine disinfected tap water. Isolation of antimutagenic components in wasabi root was done. Three components including (-)-(R)-7-methylsulfinylheptyl isothiocyanate were identified. These data show that wasabi and horseradish might be potent functional foods for keeping human health.

  3. Dividing Attention Between Tasks: Testing Whether Explicit Payoff Functions Elicit Optimal Dual-Task Performance.

    PubMed

    Farmer, George D; Janssen, Christian P; Nguyen, Anh T; Brumby, Duncan P

    2018-04-01

    We test people's ability to optimize performance across two concurrent tasks. Participants performed a number entry task while controlling a randomly moving cursor with a joystick. Participants received explicit feedback on their performance on these tasks in the form of a single combined score. This payoff function was varied between conditions to change the value of one task relative to the other. We found that participants adapted their strategy for interleaving the two tasks, by varying how long they spent on one task before switching to the other, in order to achieve the near maximum payoff available in each condition. In a second experiment, we show that this behavior is learned quickly (within 2-3 min over several discrete trials) and remained stable for as long as the payoff function did not change. The results of this work show that people are adaptive and flexible in how they prioritize and allocate attention in a dual-task setting. However, it also demonstrates some of the limits regarding people's ability to optimize payoff functions. Copyright © 2017 The Authors. Cognitive Science published by Wiley Periodicals, Inc. on behalf of Cognitive Science Society.

  4. Dual functions of a small regulatory subunit in the mitochondrial calcium uniporter complex.

    PubMed

    Tsai, Ming-Feng; Phillips, Charles B; Ranaghan, Matthew; Tsai, Chen-Wei; Wu, Yujiao; Willliams, Carole; Miller, Christopher

    2016-04-21

    Mitochondrial Ca(2+) uptake, a process crucial for bioenergetics and Ca(2+) signaling, is catalyzed by the mitochondrial calcium uniporter. The uniporter is a multi-subunit Ca(2+)-activated Ca(2+) channel, with the Ca(2+) pore formed by the MCU protein and Ca(2+)-dependent activation mediated by MICU subunits. Recently, a mitochondrial inner membrane protein EMRE was identified as a uniporter subunit absolutely required for Ca(2+) permeation. However, the molecular mechanism and regulatory purpose of EMRE remain largely unexplored. Here, we determine the transmembrane orientation of EMRE, and show that its known MCU-activating function is mediated by the interaction of transmembrane helices from both proteins. We also reveal a second function of EMRE: to maintain tight MICU regulation of the MCU pore, a role that requires EMRE to bind MICU1 using its conserved C-terminal polyaspartate tail. This dual functionality of EMRE ensures that all transport-competent uniporters are tightly regulated, responding appropriately to a dynamic intracellular Ca(2+) landscape.

  5. Evaluation of pulmonary function using single-breath-hold dual-energy computed tomography with xenon

    PubMed Central

    Kyoyama, Hiroyuki; Hirata, Yusuke; Kikuchi, Satoshi; Sakai, Kosuke; Saito, Yuriko; Mikami, Shintaro; Moriyama, Gaku; Yanagita, Hisami; Watanabe, Wataru; Otani, Katharina; Honda, Norinari; Uematsu, Kazutsugu

    2017-01-01

    Abstract Xenon-enhanced dual-energy computed tomography (xenon-enhanced CT) can provide lung ventilation maps that may be useful for assessing structural and functional abnormalities of the lung. Xenon-enhanced CT has been performed using a multiple-breath-hold technique during xenon washout. We recently developed xenon-enhanced CT using a single-breath-hold technique to assess ventilation. We sought to evaluate whether xenon-enhanced CT using a single-breath-hold technique correlates with pulmonary function testing (PFT) results. Twenty-six patients, including 11 chronic obstructive pulmonary disease (COPD) patients, underwent xenon-enhanced CT and PFT. Three of the COPD patients underwent xenon-enhanced CT before and after bronchodilator treatment. Images from xenon-CT were obtained by dual-source CT during a breath-hold after a single vital-capacity inspiration of a xenon–oxygen gas mixture. Image postprocessing by 3-material decomposition generated conventional CT and xenon-enhanced images. Low-attenuation areas on xenon images matched low-attenuation areas on conventional CT in 21 cases but matched normal-attenuation areas in 5 cases. Volumes of Hounsfield unit (HU) histograms of xenon images correlated moderately and highly with vital capacity (VC) and total lung capacity (TLC), respectively (r = 0.68 and 0.85). Means and modes of histograms weakly correlated with VC (r = 0.39 and 0.38), moderately with forced expiratory volume in 1 second (FEV1) (r = 0.59 and 0.56), weakly with the ratio of FEV1 to FVC (r = 0.46 and 0.42), and moderately with the ratio of FEV1 to its predicted value (r = 0.64 and 0.60). Mode and volume of histograms increased in 2 COPD patients after the improvement of FEV1 with bronchodilators. Inhalation of xenon gas caused no adverse effects. Xenon-enhanced CT using a single-breath-hold technique depicted functional abnormalities not detectable on thin-slice CT. Mode, mean, and volume of HU histograms of xenon images

  6. SU-F-J-91: Sparing Lung Function in Treatment Planning Using Dual Energy Tomography

    SciTech Connect

    Lapointe, A; Bahig, H; Zerouali, K

    2016-06-15

    Purpose: To propose an alternate treatment plan that minimizes the dose to the functional lung tissues. In clinical situation, the evaluation of the lung functionality is typically derived from perfusion scintigraphy. However, such technique has spatial and temporal resolutions generally inferior to those of a CT scan. Alternatively, it is possible to evaluate pulmonary function by analysing the iodine concentration determined via contrast-enhanced dual energy CT (DECT) scan. Methods: Five lung cancer patients underwent a scintigraphy and a contrast-enhanced DECT scan (SOMATOM Definition Flash, Siemens). The iodine concentration was evaluated using the two-material decomposition method to produce a functional mapmore » of the lung. The validation of the approach is realized by comparison between the differential function computed by DECT and scintigraphy. The functional map is then used to redefine the V5 (volume of the organ that received more than 5 Gy during a radiotherapy treatment) to a novel functional parameter, the V5f. The V5f, that uses a volume weighted by its function level, can assist in evaluating optimal beam entry points for a specific treatment plan. Results: The results show that the differential functions obtained by scintigraphy and DECT are in good agreement with a mean difference of 6%. In specific cases, we are able to visually correlate low iodine concentration with abnormal pulmonary lung or cancerous tumors. The comparison between V5f and V5 has shown that some entry points can be better exploited and that new ones are now accessible, 2.34 times more in average, without increasing the V5f - thus allowing easier optimization of other planning objectives. Conclusion: In addition to the high-resolution DECT images, the iodine map provides local information used to detect potential functional heterogeneities in the 3D space. We propose that this information be used to calculate new functional dose parameters such as the V5f. The presenting

  7. Does extending the dual-task functional exercises workout improve postural balance in individuals with ID?

    PubMed

    Mikolajczyk, Edyta; Jankowicz-Szymanska, Agnieszka

    2015-03-01

    Maintaining postural balance, overcoming visual and motor coordination disorders and experiencing problems with low general fitness - typical of intellectually disabled individuals - adversely affect the performance quality of their activities of daily living (ADLs). Physical fitness and postural balance can be improved by taking part in special intervention programs. Our study was designed to test whether extending the dual-task intervention program (combining ADLs with balance exercises on unstable surfaces) from 12 to 24 weeks additionally improved postural balance in individuals with intellectual disability (ID). We also attempted to assess whether the effects of the above intervention program were still noticeable after 8 weeks of holidays, in which participants did not take any rehabilitation exercises. A total of 34 adolescents, aged 14-16 years (15.06±0.9), with moderate ID took part in our study. The experimental group (E) consisted of 17 individuals, who continued the intervention program originated 3 months earlier, and the control group (C) comprised the same number of participants. Postural balance was assessed on a stabilometric platform Alfa. Having extended the workout period by another 12 weeks, we noticed that the path length of the center of pressure (COP) covered by participants on tests with their eyes open and closed significantly shortened. After a lapse of 8 weeks from the completion of the program, the experimental group revealed a statistically significant decrease in the velocity along the medio-lateral (M/L) and anterior-posterior (A/P) axes. The remaining variables stayed at the same level and the control group did not demonstrate any statistically significant changes. Dual-task exercises, in which enhancing functional tasks of daily living is combined with a parallel stimulation of balance reactions, may improve static balance in persons with ID. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Musical Training, Bilingualism, and Executive Function: A Closer Look at Task Switching and Dual-Task Performance

    ERIC Educational Resources Information Center

    Moradzadeh, Linda; Blumenthal, Galit; Wiseheart, Melody

    2015-01-01

    This study investigated whether musical training and bilingualism are associated with enhancements in specific components of executive function, namely, task switching and dual-task performance. Participants (n = 153) belonging to one of four groups (monolingual musician, bilingual musician, bilingual non-musician, or monolingual non-musician)…

  9. Two new native ß-glucosidases from Clavispora NRRL Y-50464 confer its dual function as cellobiose fermenting ethanologenic yeast

    USDA-ARS?s Scientific Manuscript database

    Clavispora NRRL Y-50464, a dual functional cellobiose fermenting and ethanologenic yeast strain, is a candidate biocatalyst for lower cost lignocellulose-to-ethanol production using simultaneous saccharification and fermentation. A ß-glucosidase BGL1 protein from this strain was recently reported an...

  10. A multi writable thiophene-based selective and reversible chromogenic fluoride probe with dual -NH functionality

    NASA Astrophysics Data System (ADS)

    Vishwakarma, Siddharth; Kumar, Ajit; Pandey, Abha; Upadhyay, K. K.

    2017-01-01

    A chromogenic fluoride probe bearing bis imine groups having dual -NH functionality (BSB) has been designed, synthesised and structurally characterized by its single crystal X-ray diffraction studies. The BSB could visually and spectroscopically recognise F- with high selectivity over other anions by exhibiting intense chromogenic response (from colourless to red) for F- in acetonitrile solution. The UV-visible titration and 1H NMR titration experiments indicated that the observed changes occur via a combined process including hydrogen bonding and deprotonation between the BSB and F-. Moreover theoretical calculations at the Density Functional Theory (DFT) level shed further light upon probe design strategy and the nature of interactions between BSB and F-. The limit of detection and binding constant of BSB towards F- were found to be 6.9 × 10- 7 M and 1.42 ± 0.069 × 108 M- 2 respectively. Finally, by using F- and H+ as chemical inputs and the absorbance as output, a INHIBIT logic gate was constructed, which exhibits "Multi-write" ability without obvious degradation in its optical output.

  11. A multi writable thiophene-based selective and reversible chromogenic fluoride probe with dual -NH functionality.

    PubMed

    Vishwakarma, Siddharth; Kumar, Ajit; Pandey, Abha; Upadhyay, K K

    2017-01-05

    A chromogenic fluoride probe bearing bis imine groups having dual -NH functionality (BSB) has been designed, synthesised and structurally characterized by its single crystal X-ray diffraction studies. The BSB could visually and spectroscopically recognise F(-) with high selectivity over other anions by exhibiting intense chromogenic response (from colourless to red) for F(-) in acetonitrile solution. The UV-visible titration and (1)H NMR titration experiments indicated that the observed changes occur via a combined process including hydrogen bonding and deprotonation between the BSB and F(-). Moreover theoretical calculations at the Density Functional Theory (DFT) level shed further light upon probe design strategy and the nature of interactions between BSB and F(-). The limit of detection and binding constant of BSB towards F(-) were found to be 6.9×10(-7)M and 1.42±0.069×10(8)M(-2) respectively. Finally, by using F(-)and H(+) as chemical inputs and the absorbance as output, a INHIBIT logic gate was constructed, which exhibits "Multi-write" ability without obvious degradation in its optical output. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. A trilayer separator with dual function for high performance lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Song, Rensheng; Fang, Ruopian; Wen, Lei; Shi, Ying; Wang, Shaogang; Li, Feng

    2016-01-01

    In this article, we propose a trilayer graphene/polypropylene/Al2O3 (GPA) separator with dual function for high performance lithium-sulfur (Li-S) batteries. Graphene is coated on one side of polypropylene (PP) separator, which functions as a conductive layer and an electrolyte reservoir that allows for rapid electron and ion transport. Then Al2O3 particles are coated on the other side to further enhance thermal stability and safety of the graphene coated polypropylene (GCP) separator, which are touched with lithium metal anode in the Li-S battery. The GPA separator shows good thermal stability after heating at 157 °C for 10 min while both GCP and PP separators showing an obvious shrinkage about 10%. The initial discharge specific capacity of Li-S coin cell with a GPA separator could reach 1067.7 mAh g-1 at 0.2C. After 100 discharge/charge cycles, it can still deliver a reversible capacity of as high as 804.4 mAh g-1 with 75% capacity retention. The pouch cells further confirm that the trilayer design has great promise towards practical applications.

  13. Designing Dual-functionalized Gels for Self-reconfiguration and Autonomous Motion

    DOE PAGES

    Kuksenok, Olga; Balazs, Anna C.

    2015-04-30

    Human motion is enabled by the concerted expansion and contraction of interconnected muscles that are powered by inherent biochemical reactions. One of the challenges in the field of biomimicry is eliciting this form of motion from purely synthetic materials, which typically do not generate internalized reactions to drive mechanical action. Moreover, for practical applications, this bio-inspired motion must be readily controllable. Herein, we develop a computational model to design a new class of polymer gels where structural reconfigurations and internalized reactions are intimately linked to produce autonomous motion, which can be directed with light. These gels contain both spirobenzopyran (SP)more » chromophores and the ruthenium catalysts that drive the oscillatory Belousov-Zhabotinsky (BZ) reaction. Importantly, both the SP moieties and the BZ reaction are photosensitive. When these dual-functionalized gels are exposed to non-uniform illumination, the localized contraction of the gel (due to the SP moieties) in the presence of traveling chemical waves (due to the BZ reaction) leads to new forms of spontaneous, self-sustained movement, which cannot be achieved by either of the mono-functionalized networks.« less

  14. A Dual Power Law Distribution for the Stellar Initial Mass Function

    NASA Astrophysics Data System (ADS)

    Hoffmann, Karl Heinz; Essex, Christopher; Basu, Shantanu; Prehl, Janett

    2018-05-01

    We introduce a new dual power law (DPL) probability distribution function for the mass distribution of stellar and substellar objects at birth, otherwise known as the initial mass function (IMF). The model contains both deterministic and stochastic elements, and provides a unified framework within which to view the formation of brown dwarfs and stars resulting from an accretion process that starts from extremely low mass seeds. It does not depend upon a top down scenario of collapsing (Jeans) masses or an initial lognormal or otherwise IMF-like distribution of seed masses. Like the modified lognormal power law (MLP) distribution, the DPL distribution has a power law at the high mass end, as a result of exponential growth of mass coupled with equally likely stopping of accretion at any time interval. Unlike the MLP, a power law decay also appears at the low mass end of the IMF. This feature is closely connected to the accretion stopping probability rising from an initially low value up to a high value. This might be associated with physical effects of ejections sometimes (i.e., rarely) stopping accretion at early times followed by outflow driven accretion stopping at later times, with the transition happening at a critical time (therefore mass). Comparing the DPL to empirical data, the critical mass is close to the substellar mass limit, suggesting that the onset of nuclear fusion plays an important role in the subsequent accretion history of a young stellar object.

  15. Designing Dual-functionalized Gels for Self-reconfiguration and Autonomous Motion

    NASA Astrophysics Data System (ADS)

    Kuksenok, Olga; Balazs, Anna C.

    2015-04-01

    Human motion is enabled by the concerted expansion and contraction of interconnected muscles that are powered by inherent biochemical reactions. One of the challenges in the field of biomimicry is eliciting this form of motion from purely synthetic materials, which typically do not generate internalized reactions to drive mechanical action. Moreover, for practical applications, this bio-inspired motion must be readily controllable. Herein, we develop a computational model to design a new class of polymer gels where structural reconfigurations and internalized reactions are intimately linked to produce autonomous motion, which can be directed with light. These gels contain both spirobenzopyran (SP) chromophores and the ruthenium catalysts that drive the oscillatory Belousov-Zhabotinsky (BZ) reaction. Importantly, both the SP moieties and the BZ reaction are photosensitive. When these dual-functionalized gels are exposed to non-uniform illumination, the localized contraction of the gel (due to the SP moieties) in the presence of traveling chemical waves (due to the BZ reaction) leads to new forms of spontaneous, self-sustained movement, which cannot be achieved by either of the mono-functionalized networks.

  16. Effects of dual-task training on balance and executive functions in Parkinson's disease: A pilot study.

    PubMed

    Fernandes, Ângela; Rocha, Nuno; Santos, Rubim; Tavares, João Manuel R S

    2015-01-01

    The aim of this study was to analyze the efficacy of cognitive-motor dual-task training compared with single-task training on balance and executive functions in individuals with Parkinson's disease. Fifteen subjects, aged between 39 and 75 years old, were randomly assigned to the dual-task training group (n = 8) and single-task training group (n = 7). The training was run twice a week for 6 weeks. The single-task group received balance training and the dual-task group performed cognitive tasks simultaneously with the balance training. There were no significant differences between the two groups at baseline. After the intervention, the results for mediolateral sway with eyes closed were significantly better for the dual-task group and anteroposterior sway with eyes closed was significantly better for the single-task group. The results suggest superior outcomes for the dual-task training compared to the single-task training for static postural control, except in anteroposterior sway with eyes closed.

  17. The orientation construction of S and N dual-doped discoid-like graphene with high-rate electrode property

    NASA Astrophysics Data System (ADS)

    Song, Xinyu; Ma, Xinlong; Ning, Guoqing; Gao, Daowei; Yu, Zhiqing; Xiao, Zhihua

    2018-06-01

    The orientation construction of S and N dual-doped discoid-like graphene (labeled as SNDG) is achieved by regular arrangement of the polycyclic aromatics in pitch molecules using natural diatomites as templates. The superior electrochemical energy storage ability of SNDG is demonstrated by cathode and anode tests, respectively. The synergistic effects of the robust scaffold coupled with the hollow structure, unique porous structure, the excellent structural stability and the dual-doping of S and N lead to the electrode property enhancement in terms of rate capability and durability. The Li ion hybrid capacitor using SNDG as both anode and cathode, presents excellent long-term cycling stability and markedly energy and power densities (up to 143 Wh kg-1 and 13,548 W kg-1). This work provides a novel pathway to realize the mass production of high-rate electrode materials via the high value-added utilization of pitch.

  18. Analysis of competition between transformation pathways in the functioning of biotic abstract dual automata.

    PubMed

    Popa, Radu; Cimpoiasu, Vily M

    2013-05-01

    Properties of avenues of transformation and their mutualism with forms of organization in dynamic systems are essential for understanding the evolution of prebiotic order. We have analyzed competition between two avenues of transformation in an A↔B system, using the simulation approach called BiADA (Biotic Abstract Dual Automata). We discuss means of avoiding common pitfalls of abstract system modeling and benefits of BiADA-based simulations. We describe the effect of the availability of free energy, energy sink magnitude, and autocatalysis on the evolution of energy flux and order in the system. Results indicate that prebiotic competition between avenues of transformation was more stringent in energy-limited environments. We predict that in such conditions the efficiency of autocatalysis during competition between alternative system states will increase for systems with forms of organization having short half-lives and thus information that is time-sensitive to energy starvation. Our results also offer a potential solution to Manfred Eigen's error catastrophe dilemma. In the conditions discussed above, the exponential growth of quasi species is curbed through the removal of less competitive "genetic" variants via energy starvation. We propose that one of the most important achievements (and selective edges) of a dynamic network during competition in energy-limited or energy-variable environments was the capacity to correlate the internal energy flux and the need for free energy with the availability of free energy in the environment.

  19. Effect of curing mode on the micro-mechanical properties of dual-cured self-adhesive resin cements.

    PubMed

    Ilie, Nicoleta; Simon, Alexander

    2012-04-01

    Light supplying to luting resin cements is impeded in several clinical situations, causing us to question whether materials can properly be cured to achieve adequately (or adequate) mechanical properties. The aim of this study was therefore to analyse the effect of light on the micro-mechanical properties of eight popular dual-cured self-adhesive resin cements by comparing them with two conventional, also dual-cured, resin cements. Four different curing procedures were applied: auto-polymerisation (dark curing) and light curing (LED unit, Freelight 2, 20 s) by applying the unit directly on the samples' surface, at a distance of 5 and 10 mm. Twenty minutes after curing, the samples were stored for 1 week at 37°C in a water-saturated atmosphere. The micro-mechanical properties-Vickers hardness, modulus of elasticity, creep and elastic/plastic deformation-were measured. Data were analysed with multivariate ANOVA followed by Tukey's test and partial eta-squared statistics (p < 0.05). A very strong influence of the material as well as filler volume and weight on the micro-mechanical properties was measured, whereas the influence of the curing procedure and type of cement-conventional or self-adhesive-was generally low. The influence of light on the polymerisation process was material dependent, with four different behaviour patterns to be distinguished. As a material category, significantly higher micro-mechanical properties were measured for the conventional compared to the self-adhesive resin cements, although this difference was low. Within the self-adhesive resin cements group, the variation in micro-mechanical properties was high. The selection of suitable resin cements should be done by considering, besides its adhesive properties, its micro-mechanical properties and curing behaviour also.

  20. Dual functional extracellular recording using a light-addressable potentiometric sensor for bitter signal transduction.

    PubMed

    Du, Liping; Wang, Jian; Chen, Wei; Zhao, Luhang; Wu, Chunsheng; Wang, Ping

    2018-08-31

    This paper presents a dual functional extracellular recording biosensor based on a light-addressable potentiometric sensor (LAPS). The design and fabrication of this biosensor make it possible to record both extracellular membrane potential changes and ATP release from a single taste bud cell for the first time. For detecting ATP release, LAPS chip was functionalized with ATP-sensitive DNA aptamer by covalent immobilization. Taste bud cells isolated from rat were cultured on LAPS surface. When the desired single taste bud cell was illuminated by modulated light, ATP release from single taste bud cells can be measured by recording the shifts of bias voltage-photocurrent curves (I-V curves) when the LAPS chip is working in discrete mode. On the other hand, extracellular membrane potential changes can be monitored by recording the fluctuation of LAPS photocurrent when the LAPS chip is working in continuous mode. The results show this biosensor can effectively record the enhancive effect of the bitter substance and inhibitory effect of the carbenoxolone (CBX) on the extracellular membrane potential changes and ATP release of single taste bud cells. In addition, the inhibitory effect of CBX also confirms LAPS extracellular recordings are originated from bitter signal transduction. It is proved this biosensor is suitable for extracellular recording of ATP release and membrane potential changes of single taste bud cells. It is suggested this biosensor could be applied to investigating taste signal transduction at the single-cell level as well as applied to other types of cells which have similar functions to taste bud cells. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Graft function assessment in mouse models of single- and dual- kidney transplantation.

    PubMed

    Wang, Lei; Wang, Ximing; Jiang, Shan; Wei, Jin; Buggs, Jacentha; Fu, Liying; Zhang, Jie; Liu, Ruisheng

    2018-05-23

    Animal models of kidney transplantation (KTX) are widely used in studying immune response of hosts to implanted grafts. Additionally, KTX can be used in generating kidney-specific knockout animal models by transplantation of kidneys from donors with global knockout of a gene to wild type recipients or vise verse. Dual kidney transplantation (DKT) provides a more physiological environment for recipients than single kidney transplantation (SKT). However, DKT in mice is rare due to technical challenges. In this study, we successfully performed DKT in mice and compared the hemodynamic response and graft function with SKT. The surgical time, complications and survival rate of DKT were not significantly different from SKT, where survival rates were above 85%. Mice with DKT showed less injury and quicker recovery with lower plasma creatinine (Pcr) and higher GFR than SKT mice (Pcr = 0.34 and 0.17 mg/dl in DKT vs. 0.50 and 0.36 mg/dl in SKT at 1 and 3 days, respectively; GFR = 215 and 131 µl/min for DKT and SKT, respectively). In addition, the DKT exhibited better renal functional reserve and long-term outcome of renal graft function than SKT based on the response to acute volume expansion. In conclusion, we have successfully generated a mouse DKT model. The hemodynamic responses of DKT better mimic physiological situations with less kidney injury and better recovery than SKT because of reduced confounding factors such as single nephron hyperfiltration. We anticipate DKT in mice will provide an additional tool for evaluation of renal significance in physiology and disease.

  2. Interactive dual-volume rendering visualization with real-time fusion and transfer function enhancement

    NASA Astrophysics Data System (ADS)

    Macready, Hugh; Kim, Jinman; Feng, David; Cai, Weidong

    2006-03-01

    Dual-modality imaging scanners combining functional PET and anatomical CT constitute a challenge in volumetric visualization that can be limited by the high computational demand and expense. This study aims at providing physicians with multi-dimensional visualization tools, in order to navigate and manipulate the data running on a consumer PC. We have maximized the utilization of pixel-shader architecture of the low-cost graphic hardware and the texture-based volume rendering to provide visualization tools with high degree of interactivity. All the software was developed using OpenGL and Silicon Graphics Inc. Volumizer, tested on a Pentium mobile CPU on a PC notebook with 64M graphic memory. We render the individual modalities separately, and performing real-time per-voxel fusion. We designed a novel "alpha-spike" transfer function to interactively identify structure of interest from volume rendering of PET/CT. This works by assigning a non-linear opacity to the voxels, thus, allowing the physician to selectively eliminate or reveal information from the PET/CT volumes. As the PET and CT are rendered independently, manipulations can be applied to individual volumes, for instance, the application of transfer function to CT to reveal the lung boundary while adjusting the fusion ration between the CT and PET to enhance the contrast of a tumour region, with the resultant manipulated data sets fused together in real-time as the adjustments are made. In addition to conventional navigation and manipulation tools, such as scaling, LUT, volume slicing, and others, our strategy permits efficient visualization of PET/CT volume rendering which can potentially aid in interpretation and diagnosis.

  3. Insights into the Formation and Properties of Templated Dual Mesoporous Titania with Enhanced Photocatalytic Activity.

    PubMed

    Naboulsi, Issam; Lebeau, Bénédicte; Michelin, Laure; Carteret, Cédric; Vidal, Loic; Bonne, Magali; Blin, Jean-Luc

    2017-01-25

    The one pot synthesis of dual mesoporous titania (2.3 and 7.7 nm) has been achieved from a mixture of fluorinated and Pluronic surfactants. The small and large mesopore networks are templated, respectively, by a fluorinated-rich liquid crystal and a Pluronic-rich liquid crystal, which are in equilibrium. After calcination at 350 °C, the amorphous walls are transformed into semicrystalline anatase preserving the mesoporous structure. Results concerning the photodegradation of methyl orange using the calcined photocatalysts highlight that the kinetic rate constant (k) determined for the dual mesoporous titania is 2.6 times higher than the k value obtained for the monomodal ones.

  4. Dual functionalized graphene oxide serves as a carrier for delivering oligohistidine- and biotin-tagged biomolecules into cells.

    PubMed

    Jana, Batakrishna; Mondal, Goutam; Biswas, Atanu; Chakraborty, Indrani; Saha, Abhijit; Kurkute, Prashant; Ghosh, Surajit

    2013-11-01

    A versatile method of dual chemical functionalization of graphene oxide (GO) with Tris-[nitrilotris(acetic acid)] (Tris-NTA) and biotin for cellular delivery of oligohistidine- and biotin-tagged biomolecules is reported. Orthogonally functionalized GO surfaces with Tris-NTA and biotin to obtain a dual-functionalized GO (DFGO) are prepared and characterized by various spectroscopic and microscopic techniques. Fluorescence microscopic images reveal that DFGO surfaces are capable of binding oligohistidine-tagged biomolecules/proteins and avidin/biotin-tagged biomolecules/proteins orthogonally. The DFGO nanoparticles are non-cytotoxic in nature and can deliver oligohistidine- and biotin-tagged biomolecules simultaneously into the cell. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Water-soluble porphyrins as a dual-function molecular imaging platform for MRI and fluorescence zinc sensing

    PubMed Central

    Zhang, Xiao-an; Lovejoy, Katherine S.; Jasanoff, Alan; Lippard, Stephen J.

    2007-01-01

    We report a molecular platform for dual-function fluorescence/MRI sensing of mobile zinc. Zinc-selective binding units were strategically attached to a water-soluble porphyrin template. The synthetic strategy for achieving the designed target ligand is flexible and convenient, and the key intermediates can be applied as general building blocks for the construction of other metal sensors based on a similar mechanism. The metal-free form, (DPA-C2)2-TPPS3 (1), where DPA is dipicolylamine and TPPS3 is 5-phenyl-10,15,20-tris(4-sulfonatophenyl)porphine, is an excellent fluorescent sensor for zinc. It has certain superior physical properties compared with earlier-generation zinc sensors including emission in the red and near-IR regions [λem = 645 nm (s) and 715 nm (m)], with a large Stokes shift of >230 nm. The fluorescence intensity of 1 increases by >10-fold upon zinc binding. The fluorescence “turn-on” is highly selective for zinc versus other divalent metal ions and is relatively pH-insensitive within the biologically relevant pH window. The manganese derivative, [(DPA-C2)2-TPPS3Mn(III)] (2), switches the function of the molecule to generate an MRI contrast agent. In the presence of zinc, the relaxivity of 2 in aqueous solution is significantly altered, which makes it a promising zinc MRI sensor. Both metal-free and Mn(III)-inserted forms are efficiently taken up by live cells, and the intracellular zinc can be imaged by either fluorescence or MR, respectively. We anticipate that in vivo applications of the probes will facilitate a deeper understanding of the physiological roles of zinc and allow detection of abnormal zinc homeostasis for pathological diagnoses. PMID:17578918

  6. Seed birth to death: dual functions of reactive oxygen species in seed physiology.

    PubMed

    Jeevan Kumar, S P; Rajendra Prasad, S; Banerjee, Rintu; Thammineni, Chakradhar

    2015-09-01

    Reactive oxygen species (ROS) are considered to be detrimental to seed viability. However, recent studies have demonstrated that ROS have key roles in seed germination particularly in the release of seed dormancy and embryogenesis, as well as in protection from pathogens. This review considers the functions of ROS in seed physiology. ROS are present in all cells and at all phases of the seed life cycle. ROS accumulation is important in breaking seed dormancy, and stimulating seed germination and protection from pathogens. However, excessive ROS accumulation can be detrimental. Therefore, knowledge of the mechanisms by which ROS influence seed physiology will provide insights that may not only allow the development of seed quality markers but also help us understand how dormancy can be broken in several recalcitrant species. Reactive oxygen species have a dual role in seed physiology. Understanding the relative importance of beneficial and detrimental effects of ROS provides great scope for the improvement and maintenance of seed vigour and quality, factors that may ultimately increase crop yields. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Efficient removal of methyl orange using Cu2O as a dual function catalyst

    NASA Astrophysics Data System (ADS)

    Zhang, Fan; Dong, Guohui; Wang, Mian; Zeng, Yubin; Wang, Chuanyi

    2018-06-01

    In this study, we synthesized Cu2O particles with rough surfaces by a facile solvothermal method as a dual-function material that can degrade contaminants not only under light irradiation but also in dark circumstance. Both the as-prepared Cu2O and commercial Cu2O exhibited excellent performance for the removal of methyl orange under visible light irradiation through a photocatalysis-based strategy. However, the former was found to show remarkable capability under dark circumstances by means of molecular oxygen activation, while the latter performed poor efficiently under the same condition. This significant difference of performances under dark circumstances was related to rich oxygen vacancies existed on the as-prepared Cu2O surfaces that are associated with the single-electron reduction of O2 to generate radO2-, which play a dominant role in the generation of Cu+. In addition, Cu+ was identified to play key roles in the broken of azo bond. Then, the generated intermediates were mineralized by radOH generated through molecular oxygen activation process. This study could not only deep the understanding of the MO removal mechanism by Cu2O but also show a novel direction of amphibious application for photocatalytic materials.

  8. Dual Kidney Transplantation Offers a Valuable Source for Kidneys With Good Functional Outcome.

    PubMed

    Khalid, U; Asderakis, A; Rana, T; Szabo, L; Chavez, R; Ilham, M A; Ablorsu, E

    2016-01-01

    Reasons for declining kidney donors are older age, with or without, hypertension, kidney dysfunction, and diabetes. Implantation of both kidneys into a single recipient from such donors may improve their acceptability and outcome. Patients who underwent dual kidney transplantation (DKT) between June 2010 and May 2014 were identified from a prospectively maintained database. Single kidney transplantations (SKT) with matching donor criteria were also identified. Donors considered for DKT were the following: DBDs >70 years of age with diabetes and/or hypertension; DCDs >65 years of age with diabetes and/or hypertension; and DCDs >70 years of age. Over a 4-year period, 34 patients underwent adult DKT, and 51, with matching donor criteria, underwent SKT. The median estimated glomerular filtration rate (eGFR) at 12 and 36 months of DKT was 49 (range, 5-79) and 42 (range, 15-85) mL/min compared with SKT of 35 (range, 10-65) and 32 (range, 6-65), respectively. The 1-year graft survival for DKT and SKT was 88% and 96% (P = .52), and patient survival was 94% and 98%, respectively (P = .12). Median hospital stay, intensive care unit admission, and wound complications were more frequent in the DKT group. Graft function following DKT is significantly better compared with matched criteria SKT; graft and patient survival are similar. There is an increased rate of complications following DKT, with longer hospital stay and ICU admission. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Dual-Functional Nanoparticles Targeting CXCR4 and Delivering Antiangiogenic siRNA Ameliorate Liver Fibrosis.

    PubMed

    Liu, Chun-Hung; Chan, Kun-Ming; Chiang, Tsaiyu; Liu, Jia-Yu; Chern, Guann-Gen; Hsu, Fu-Fei; Wu, Yu-Hsuan; Liu, Ya-Chi; Chen, Yunching

    2016-07-05

    The progression of liver fibrosis, an intrinsic response to chronic liver injury, is associated with hepatic hypoxia, angiogenesis, abnormal inflammation, and significant matrix deposition, leading to the development of cirrhosis and hepatocellular carcinoma (HCC). Due to the complex pathogenesis of liver fibrosis, antifibrotic drug development has faced the challenge of efficiently and specifically targeting multiple pathogenic mechanisms. Therefore, CXCR4-targeted nanoparticles (NPs) were formulated to deliver siRNAs against vascular endothelial growth factor (VEGF) into fibrotic livers to block angiogenesis during the progression of liver fibrosis. AMD3100, a CXCR4 antagonist that was incorporated into the NPs, served dual functions: it acted as a targeting moiety and suppressed the progression of fibrosis by inhibiting the proliferation and activation of hepatic stellate cells (HSCs). We demonstrated that CXCR4-targeted NPs could deliver VEGF siRNAs to fibrotic livers, decrease VEGF expression, suppress angiogenesis and normalize the distorted vessels in the fibrotic livers in the carbon tetrachloride (CCl4) induced mouse model. Moreover, blocking SDF-1α/CXCR4 by CXCR4-targeted NPs in combination with VEGF siRNA significantly prevented the progression of liver fibrosis in CCl4-treated mice. In conclusion, the multifunctional CXCR4-targeted NPs delivering VEGF siRNAs provide an effective antifibrotic therapeutic strategy.

  10. Dual-Functionalization Device for Therapy through Dopamine Release and Monitoring.

    PubMed

    Fabregat, Georgina; Giménez, Alessia; Díaz, Angélica; Puiggalí, Jordi; Alemán, Carlos

    2018-05-01

    A dual-functional device is fabricated to release progressively dopamine (DA) from a biohydrogel under real-time monitoring via electrochemical detection. For this purpose, a poly-γ-glutamic acid biohydrogel is assembled with a poly(3,4-ethylenedioxythiophene) (PEDOT) layer, previously deposited onto a screen printed electrode. The biohydrogel is formulated to achieve dimensional stability and maximum DA-loading capacity. Conditions for DA-loading are influenced by the oxidation of the neurotransmitter in acid environments and the poor resistance of PEDOT to the lyophilization. The performance of the device is proved in a medium with the physiological pH of blood and the cerebrospinal fluid. The progressive release of DA is successfully monitored by the device, the limit of detection and sensitivity of the integrated sensor being 450 × 10 -9 m and 8 × 10 -5 mA µm -1 , respectively. The effect of electrochemical stimulation in the kinetics of the DA release is also investigated applying potential ramps in cyclic phase to alter the biohydrogel morphology. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Structure-function properties of anticorrosive exopolyaccharides

    USDA-ARS?s Scientific Manuscript database

    Nanoscale biobased exopolymer films were shown that provide protection to metal substrates under corrosive environments and that the films could be self-repairing in aqueous environments. This work describes the fundamental properties of thin exopolymer films including thermodynamic properties, film...

  12. Effect of processing on functional properties of animal blood plasma.

    PubMed

    Del Hoyo, P; Rendueles, M; Díaz, M

    2008-04-01

    A number of functional and physical properties such as solubility, foam capacity, emulsifying stability and interfacial tension were compared for standard plasma, plasma decationed by ion exchange and plasma deionized by ultrafiltration (UF). The changes in functional properties can determine the use of a protein as an additive to a food product or invalidate its use. All samples had good functional properties and hence could be used in the formulation of food products. Results showed that ion exchange and UF improved emulsifying capacity while having little effect on the other functional properties.

  13. A dual RF resonator system for high-field functional magnetic resonance imaging of small animals.

    PubMed

    Ludwig, R; Bodgdanov, G; King, J; Allard, A; Ferris, C F

    2004-01-30

    A new apparatus has been developed that integrates an animal restrainer arrangement for small animals with an actively tunable/detunable dual radio-frequency (RF) coil system for in vivo anatomical and functional magnetic resonance imaging of small animals at 4.7 T. The radio-frequency coil features an eight-element microstrip line configuration that, in conjunction with a segmented outer copper shield, forms a transversal electromagnetic (TEM) resonator structure. Matching and active tuning/detuning is achieved through fixed/variable capacitors and a PIN diode for each resonator element. These components along with radio-frequency chokes (RFCs) and blocking capacitors are placed on two printed circuit boards (PCBs) whose copper coated ground planes form the front and back of the volume coil and are therefore an integral part of the resonator structure. The magnetic resonance signal response is received with a dome-shaped single-loop surface coil that can be height-adjustable with respect to the animal's head. The conscious animal is immobilized through a mechanical arrangement that consists of a Plexiglas body tube and a head restrainer. This restrainer has a cylindrical holder with a mouthpiece and position screws to receive and restrain the head of the animal. The apparatus is intended to perform anatomical and functional magnetic resonance imaging in conscious animals such as mice, rats, hamsters, and marmosets. Cranial images acquired from fully conscious rats in a 4.7 T Bruker 40 cm bore animal scanner underscore the feasibility of this approach and bode well to extend this system to the imaging of other animals.

  14. Dual effect of local anesthetics on the function of excitable rod outer segment disk membrane

    SciTech Connect

    Mashimo, T.; Abe, K.; Yoshiya, I.

    1986-04-01

    The effects of local anesthetics and a divalent cation, Ca2+, on the function of rhodopsin were estimated from the measurements of light-induced proton uptake. The light-induced proton uptake by rhodopsin in the rod outer segment disk membrane was enhanced at lower pH (4) but depressed at higher pHs (6 to 8) by the tertiary amine local anesthetics lidocaine, bupivacaine, tetracaine, and dibucaine. The order of local anesthetic-induced depression of the proton uptake followed that of their clinical anesthetic potencies. The depression of the proton uptake versus the concentration of the uncharged form of local anesthetic nearly describes the same curvemore » for small and large dose of added anesthetic. Furthermore, a neutral local anesthetic, benzocaine, depressed the proton uptake at all pHs between 4 and 7. These results indicate that the depression of the proton uptake is due to the effect of only the uncharged form. It is hypothesized that the uncharged form of local anesthetics interacts hydrophobically with the rhodopsin in the disk membrane. The dual effect of local anesthetics on the proton uptake, on the other hand, suggests that the activation of the function of rhodopsin may be caused by the charged form. There was no significant change in the light-induced proton uptake by rhodopsin when 1 mM of Ca2+ was introduced into the disk membrane at varying pHs in the absence or presence of local anesthetics. This fact indicates that Ca2+ ion does not influence the diprotonating process of metarhodopsin; neither does it interfere with the local anesthetic-induced changes in the rhodopsin molecule.« less

  15. Copper-doped titanium dioxide nanoparticles as dual-functional labels for fabrication of electrochemical immunosensors.

    PubMed

    Zhang, Sen; Ma, Hongmin; Yan, Liangguo; Cao, Wei; Yan, Tao; Wei, Qin; Du, Bin

    2014-09-15

    Constructions of versatile electroactive labels are key issues in the development of electrochemical immunosensors. In this study, copper-doped titanium dioxide nanoparticle (Cu@TiO2) was synthesized and used as labels for fabrication of sandwich-type electrochemical immunosensors on glassy carbon electrode (GCE). Due to the presence of copper ions, Cu@TiO2 shows a strong response current when coupled to an electrode. The prepared nanocomposite also shows high electrocatalytic activity towards reduction of hydrogen peroxide (H2O2). The dual functionality of Cu@TiO2 enables the fabrication of immunosensor using different detection modes, that is, square wave voltammetry (SWV) or chronoamperometry (CA). While Cu@TiO2 was used as labels of secondary antibodies (Ab2), carboxyl functionalized graphene oxide (CFGO) was used as electrode materials to immobilize primary antibodies (Ab1). Using human immunoglobulin G (IgG) as a model analyte, the immunosensor shows high sensitivity, acceptable stability and good reproducibility for both detection modes. Under optimal conditions, a linear range from 0.1 pg/mL to 100 ng/mL with a detection limit of 0.052 pg/mL was obtained for SWV analysis. For CA analysis, a wider linear range from 0.01 pg/mL to 100 ng/mL and a lower detection limit of 0.0043 pg/mL were obtained. The proposed metal ion-based enzyme-free and noble metal-free immunosensor may have promising applications in clinical diagnoses and many other fields. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. The dual-function chaperone HycH improves assembly of the formate hydrogenlyase complex.

    PubMed

    Lindenstrauß, Ute; Skorupa, Philipp; McDowall, Jennifer S; Sargent, Frank; Pinske, Constanze

    2017-08-11

    The assembly of multi-protein complexes requires the concerted synthesis and maturation of its components and subsequently their co-ordinated interaction. The membrane-bound formate hydrogenlyase (FHL) complex is the primary hydrogen-producing enzyme in Escherichia coli and is composed of seven subunits mostly encoded within the hycA-I operon for [NiFe]-hydrogenase-3 (Hyd-3). The HycH protein is predicted to have an accessory function and is not part of the final structural FHL complex. In this work, a mutant strain devoid of HycH was characterised and found to have significantly reduced FHL activity due to the instability of the electron transfer subunits. HycH was shown to interact specifically with the unprocessed species of HycE, the catalytic hydrogenase subunit of the FHL complex, at different stages during the maturation and assembly of the complex. Variants of HycH were generated with the aim of identifying interacting residues and those that influence activity. The R70/71/K72, the Y79, the E81 and the Y128 variant exchanges interrupt the interaction with HycE without influencing the FHL activity. In contrast, FHL activity, but not the interaction with HycE, was negatively influenced by H37 exchanges with polar residues. Finally, a HycH Y30 variant was unstable. Surprisingly, an overlapping function between HycH with its homologous counterpart HyfJ from the operon encoding [NiFe]-hydrogenase-4 (Hyd-4) was identified and this is the first example of sharing maturation machinery components between Hyd-3 and Hyd-4 complexes. The data presented here show that HycH has a novel dual role as an assembly chaperone for a cytoplasmic [NiFe]-hydrogenase. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  17. Smart dual-functional warhead for folate receptor-specific activatable imaging and photodynamic therapy.

    PubMed

    Kim, Jisu; Tung, Ching-Hsuan; Choi, Yongdoo

    2014-09-21

    A smart dual-targeted theranostic agent becomes highly fluorescent and phototoxic only when its linker is cleaved by tumor-associated lysosomal enzyme cathepsin B after internalization into folate receptor-positive cancer cells.

  18. Effects of dual antibacterial agents MDPB and nano-silver in primer on microcosm biofilm, cytotoxicity and dentin bond properties

    PubMed Central

    Zhang, Ke; Cheng, Lei; Imazato, Satoshi; Antonucci, Joseph M.; Lin, Nancy J.; Lin-Gibson, Sheng; Bai, Yuxing; Xu, Hockin H. K.

    2013-01-01

    Objectives The objective of this study was to investigate the effects of dentin primer containing dual antibacterial agents, namely, 12-methacryloyloxydodecylpyridinium bromide (MDPB) and nanoparticles of silver (NAg), on dentin bond strength, dental plaque microcosm biofilm response, and fibroblast cytotoxicity for the first time. Methods Scotchbond Multi-Purpose (SBMP) was used as the parent bonding agent. Four primers were tested: SBMP primer control (referred to as “P”), P+5%MDPB, P+0.05%NAg, and P+5%MDPB+0.05%NAg. Dentin shear bond strengths were measured using extracted human teeth. Biofilms from the mixed saliva of 10 donors were cultured to investigate metabolic activity, colony-forming units (CFU), and lactic acid production. Human fibroblast cytotoxicity of the four primers was tested in vitro. Results Incorporating MDPB and NAg into primer did not reduce dentin bond strength compared to control (p>0.1). SEM revealed well-bonded adhesive-dentin interfaces with numerous resin tags. MDPB or NAg each greatly reduced biofilm viability and acid production, compared to control. Dual agents MDPB+NAg had a much stronger effect than either agent alone (p<0.05), increasing inhibition zone size and reducing metabolic activity, CFU and lactic acid by an order of magnitude, compared to control. There was no difference in cytotoxicity between commercial control and antibacterial primers (p>0.1). Conclusions The method of using dual agents MDPB+NAg in the primer yielded potent antibacterial properties. Hence, this method may be promising to combat residual bacteria in tooth cavity and invading bacteria at the margins. The dual agents MDPB+NAg may have wide applicability to other adhesives, composites, sealants and cements to inhibit biofilms and caries. PMID:23402889

  19. Musical training, bilingualism, and executive function: a closer look at task switching and dual-task performance.

    PubMed

    Moradzadeh, Linda; Blumenthal, Galit; Wiseheart, Melody

    2015-07-01

    This study investigated whether musical training and bilingualism are associated with enhancements in specific components of executive function, namely, task switching and dual-task performance. Participants (n = 153) belonging to one of four groups (monolingual musician, bilingual musician, bilingual non-musician, or monolingual non-musician) were matched on age and socioeconomic status and administered task switching and dual-task paradigms. Results demonstrated reduced global and local switch costs in musicians compared with non-musicians, suggesting that musical training can contribute to increased efficiency in the ability to shift flexibly between mental sets. On dual-task performance, musicians also outperformed non-musicians. There was neither a cognitive advantage for bilinguals relative to monolinguals, nor an interaction between music and language to suggest additive effects of both types of experience. These findings demonstrate that long-term musical training is associated with improvements in task switching and dual-task performance. Copyright © 2014 Cognitive Science Society, Inc.

  20. Dual Functioning Thieno-Pyrrole Fused BODIPY Dyes for NIR Optical Imaging and Photodynamic Therapy: Singlet Oxygen Generation without Heavy Halogen Atom Assistance.

    PubMed

    Watley, Ryan L; Awuah, Samuel G; Bio, Moses; Cantu, Robert; Gobeze, Habtom B; Nesterov, Vladimir N; Das, Sushanta K; D'Souza, Francis; You, Youngjae

    2015-06-01

    We discovered a rare phenomenon wherein a thieno-pyrrole fused BODIPY dye (SBDPiR690) generates singlet oxygen without heavy halogen atom substituents. SBDPiR690 generates both singlet oxygen and fluorescence. To our knowledge, this is the first example of such a finding. To establish a structure-photophysical property relationship, we prepared SBDPiR analogs with electron-withdrawing groups at the para-position of the phenyl groups. The electron-withdrawing groups increased the HOMO-LUMO energy gap and singlet oxygen generation. Among the analogs, SBDPiR688, a CF3 analog, had an excellent dual functionality of brightness (82290 m(-1)  cm(-1) ) and phototoxic power (99170 m(-1)  cm(-1) ) comparable to those of Pc 4, due to a high extinction coefficient (211 000 m(-1)  cm(-1) ) and balanced decay (Φflu =0.39 and ΦΔ =0.47). The dual functionality of the lead compound SBDPiR690 was successfully applied to preclinical optical imaging and for PDT to effectively control a subcutaneous tumor. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Dual AAV therapy ameliorates exercise-induced muscle injury and functional ischemia in murine models of Duchenne muscular dystrophy.

    PubMed

    Zhang, Yadong; Yue, Yongping; Li, Liang; Hakim, Chady H; Zhang, Keqing; Thomas, Gail D; Duan, Dongsheng

    2013-09-15

    Neuronal nitric oxide synthase (nNOS) membrane delocalization contributes to the pathogenesis of Duchenne muscular dystrophy (DMD) by promoting functional muscle ischemia and exacerbating muscle injury during exercise. We have previously shown that supra-physiological expression of nNOS-binding mini-dystrophin restores normal blood flow regulation and prevents functional ischemia in transgenic mdx mice, a DMD model. A critical next issue is whether systemic dual adeno-associated virus (AAV) gene therapy can restore nNOS-binding mini-dystrophin expression and mitigate muscle activity-related functional ischemia and injury. Here, we performed systemic gene transfer in mdx and mdx4cv mice using a pair of dual AAV vectors that expressed a 6 kb nNOS-binding mini-dystrophin gene. Vectors were packaged in tyrosine mutant AAV-9 and co-injected (5 × 10(12) viral genome particles/vector/mouse) via the tail vein to 1-month-old dystrophin-null mice. Four months later, we observed 30-50% mini-dystrophin positive myofibers in limb muscles. Treatment ameliorated histopathology, increased muscle force and protected against eccentric contraction-induced injury. Importantly, dual AAV therapy successfully prevented chronic exercise-induced muscle force drop. Doppler hemodynamic assay further showed that therapy attenuated adrenergic vasoconstriction in contracting muscle. Our results suggest that partial transduction can still ameliorate nNOS delocalization-associated functional deficiency. Further evaluation of nNOS binding mini-dystrophin dual AAV vectors is warranted in dystrophic dogs and eventually in human patients.

  2. Modeling the emissions of a dual fuel engine coupled with a biomass gasifier-supplementing the Wiebe function.

    PubMed

    Vakalis, Stergios; Caligiuri, Carlo; Moustakas, Konstantinos; Malamis, Dimitris; Renzi, Massimiliano; Baratieri, Marco

    2018-03-12

    There is a growing market demand for small-scale biomass gasifiers that is driven by the economic incentives and the legislative framework. Small-scale gasifiers produce a gaseous fuel, commonly referred to as producer gas, with relatively low heating value. Thus, the most common energy conversion systems that are coupled with small-scale gasifiers are internal combustion engines. In order to increase the electrical efficiency, the operators choose dual fuel engines and mix the producer gas with diesel. The Wiebe function has been a valuable tool for assessing the efficiency of dual fuel internal combustion engines. This study introduces a thermodynamic model that works in parallel with the Wiebe function and calculates the emissions of the engines. This "vis-à-vis" approach takes into consideration the actual conditions inside the cylinders-as they are returned by the Wiebe function-and calculates the final thermodynamic equilibrium of the flue gases mixture. This approach aims to enhance the operation of the dual fuel internal combustion engines by identifying the optimal operating conditions and-at the same time-advance pollution control and minimize the environmental impact.

  3. Density-tunable lightweight polymer composites with dual-functional ability of efficient EMI shielding and heat dissipation.

    PubMed

    Lee, Seung Hwan; Yu, Seunggun; Shahzad, Faisal; Kim, Woo Nyon; Park, Cheolmin; Hong, Soon Man; Koo, Chong Min

    2017-09-21

    Lightweight dual-functional materials with high EMI shielding performance and thermal conductivity are of great importance in modern cutting-edge applications, such as mobile electronics, automotive, aerospace, and military. Unfortunately, a clear material solution has not emerged yet. Herein, we demonstrate a simple and effective way to fabricate lightweight metal-based polymer composites with dual-functional ability of excellent EMI shielding effectiveness and thermal conductivity using expandable polymer bead-templated Cu hollow beads. The low-density Cu hollow beads (ρ ∼ 0.44 g cm -3 ) were fabricated through electroless plating of Cu on the expanded polymer beads with ultralow density (ρ ∼ 0.02 g cm -3 ). The resulting composites that formed a continuous 3D Cu network with a very small Cu content (∼9.8 vol%) exhibited excellent EMI shielding (110.7 dB at 7 GHz) and thermal conductivity (7.0 W m -1 K -1 ) with isotropic features. Moreover, the densities of the composites are tunable from 1.28 to 0.59 g cm -3 in accordance with the purpose of their applications. To the best of our knowledge, the resulting composites are the best lightweight dual-functional materials with exceptionally high EMI SE and thermal conductivity performance among synthetic polymer composites.

  4. Pt-decorated zinc oxide nanorod arrays with graphitic carbon nitride nanosheets for highly efficient dual-functional gas sensing.

    PubMed

    Tian, Hailin; Fan, Huiqing; Ma, Jiangwei; Liu, Zhiyong; Ma, Longtao; Lei, Shenhui; Fang, Jiawen; Long, Changbai

    2018-01-05

    In this work, well-aligned ZnO nanorods were grown on the substrate of exfoliated g-C 3 N 4 nanosheets via a microwave-assisted hydrothermal synthesis, and then Pt/ZnO/g-C 3 N 4 nanostructures were obtained after the deposition of Pt nanoparticles. The growth of vertically ordered ZnO nanorods was occurred on g-C 3 N 4 nanosheets through the bonding interaction between Zn and N atoms, which was confirmed by XPS, FT-IR data and molecular orbital theory. The Pt/ZnO/g-C 3 N 4 nanostructures sensor exhibited the remarkable sensitivity, selectivity, and fast response/recovery time for air pollutants of ethanol and NO 2 . The application of Pt/ZnO/g-C 3 N 4 nanostructures could be used as a dual-functional gas sensor through the controlled working temperature. Besides, the Pt/ZnO/g-C 3 N 4 nanostructures sensor could be applied to the repeating detection of ethanol and NO 2 in the natural environment. The synergistic effect and improved the separation of electron-hole pairs in Pt/ZnO/g-C 3 N 4 nanostructures had been verified for the gas sensing mechanism. Additionally, Pt/ZnO/g-C 3 N 4 nanostructures revealed the excellent charge carriers transport properties in electrochemical impedance spectroscopy (EIS), such as the longer electron lifetime (τ n ), higher electron diffusion coefficient (D n ) and bigger effective diffusion length (L n ), which also played an important role for Pt/ZnO/g-C 3 N 4 nanostructures with striking gas sensing activities. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Dual functional bioactive-peptide, AIMP1-derived peptide (AdP), for anti-aging.

    PubMed

    Kim, Jina; Kang, Sujin; Kwon, HanJin; Moon, HoSang; Park, Min Chul

    2018-06-19

    Human skin aging is caused by several factors, such as UV irradiation, stress, hormone, and pollution. Wrinkle formation and skin pigmentation are representative features of skin aging. Although EGF and arbutin are used as anti-wrinkle and skin whitening agents, respectively, they have adverse effects on skin. When more cosmeceutical ingredients are added to cosmetic product, adverse effects are also accumulated. For these reasons, multifunctional and safe cosmetic ingredients are in demand. The aim of the present study is to investigate the novel anti-aging agents, AIMP1-derived peptide (AdP, INCI name: sh-oligopeptide-5/sh-oligopeptide SP) for cosmetic products. To assess the anti-wrinkle effect of AdP, collagen type I synthesis and fibroblast proliferation were determined on human fibroblasts. The anti-wrinkle effect of AdP was examined by ELISA and cell titer glo assay. To assess the whitening, melanin content and tyrosinase activity were determined on melanocytes. The whitening effect of AdP was examined by melanin measurement and enzyme activity assay. The safety of AdP was determined by cytotoxicity and immunogenicity, CCK-8 and TNF-α ELISA assay, respectively. AdP treatment induced the collagen type I synthesis and fibroblast proliferation. Also, AdP treatment inhibited melanin synthesis by regulating tyrosinase activity. The anti-aging effect of AdP is more potent than EGF and albutin. AdP did not show adverse effects. These results show that AdP can be dual functional and safe cosmeceutical agent to prevent skin aging. © 2018 Wiley Periodicals, Inc.

  6. Development of Low Carbon Niobium Bearing High Strength F-B Dual Phase Steel with High Hole Expansion Property

    NASA Astrophysics Data System (ADS)

    Zhang, Lin; Xia, Ming-sheng; Xiong, Zi-liu; Du, Yan-bing; Qiao, Zhi-ming; Zhang, Hong-bo

    In the study a low carbon niobium bearing high strength F-B dual phase automobile steel with high hole expansion property has been investigated. Steels of different chemical composition have been investigated by simulation experiments of controlled rolling and cooling process to study the influences of chemical elements, especially for C,Nb and Ti, and cooling pattern on the mechanical properties, flangeability and microstructure of strips. So-called 3-stages cooling pattern was adopted in simulation experiments, combining ultra fast cooling in first stage, air cooling in middle stage and fast cooling in the last stage, and at the end of run-out table the temperature of rolled pieces drop to below Bs point. Optical microstructure and SEM morphology have been observed. Results indicate that it is possible to obtain dual phase microstructure of polygonal ferrite plus bainite in adopting 3-stages cooling pattern. The low temperature coiling method using 3-step controlled cooling pattern after hot rolling is effective to produce low carbon Nb bearing steel with high balance of strength-ductility-flangeability, in addition, higher carbon content of steel tend to be detrimental to flangeability of steel, due to much carbide precipitation at ferrite boundary. Based on the results of simulation experiments mill trial has been carried out and hot rolled high strength steel with tensile strength higher as 600Mpa and hole expansion ratio higher as 100% has been developed successfully.

  7. Rheological properties of styrene-butadiene rubber filled with electron beam modified surface treated dual phase fillers

    NASA Astrophysics Data System (ADS)

    Shanmugharaj, A. M.; Bhowmick, Anil K.

    2004-01-01

    The rheological properties of styrene-butadiene rubber (SBR) loaded with dual phase filler were measured using Monsanto Processability Tester (MPT) at three different temperatures (100°C, 110°C and 130°C) and four different shear rates (61.3, 306.3, 613, and 1004.5 s -1). The effect of electron beam modification of dual phase filler in absence and presence of trimethylol propane triacrylate (TMPTA) or triethoxysilylpropyltetrasulphide (Si-69) on melt flow properties of SBR was also studied. The viscosity of all the systems decreases with shear rate indicating their pseudoplastic or shear thinning nature. The higher shear viscosity for the SBR loaded with the electron beam modified filler is explained in terms of variation in structure of the filler upon electron beam irradiation. Die swell of the modified filler loaded SBR is slightly higher than that of the unmodified filler loaded rubber, which is explained by calculating normal stress difference for the systems. Activation energy of the modified filler loaded SBR systems is also slightly higher than that of the control filler loaded SBR system.

  8. Functional properties of teff and oat composites

    USDA-ARS?s Scientific Manuscript database

    Teff-oat composites were developed using gluten free teff flour containing essential amino acids and minerals along with oat products containing ß-glucan known for lowering blood cholesterol. Teff-oat composites were evaluated for their pasting and rheological properties by a Rapid Visco Analyzer (R...

  9. Starch and protein chemistry and functional properties

    USDA-ARS?s Scientific Manuscript database

    Starch and protein are the major constituents of all cereal grains and are an important source of nutrition for humans and animals. Worldwide, sorghum and the millets are basic food staples for millions of people and are important sources of animal feed, and in some cases fuel. The chemical properti...

  10. Classification and Analysis of Regulatory Pathways Using Graph Property, Biochemical and Physicochemical Property, and Functional Property

    PubMed Central

    Cai, Yu-Dong; Chou, Kuo-Chen

    2011-01-01

    Given a regulatory pathway system consisting of a set of proteins, can we predict which pathway class it belongs to? Such a problem is closely related to the biological function of the pathway in cells and hence is quite fundamental and essential in systems biology and proteomics. This is also an extremely difficult and challenging problem due to its complexity. To address this problem, a novel approach was developed that can be used to predict query pathways among the following six functional categories: (i) “Metabolism”, (ii) “Genetic Information Processing”, (iii) “Environmental Information Processing”, (iv) “Cellular Processes”, (v) “Organismal Systems”, and (vi) “Human Diseases”. The prediction method was established trough the following procedures: (i) according to the general form of pseudo amino acid composition (PseAAC), each of the pathways concerned is formulated as a 5570-D (dimensional) vector; (ii) each of components in the 5570-D vector was derived by a series of feature extractions from the pathway system according to its graphic property, biochemical and physicochemical property, as well as functional property; (iii) the minimum redundancy maximum relevance (mRMR) method was adopted to operate the prediction. A cross-validation by the jackknife test on a benchmark dataset consisting of 146 regulatory pathways indicated that an overall success rate of 78.8% was achieved by our method in identifying query pathways among the above six classes, indicating the outcome is quite promising and encouraging. To the best of our knowledge, the current study represents the first effort in attempting to identity the type of a pathway system or its biological function. It is anticipated that our report may stimulate a series of follow-up investigations in this new and challenging area. PMID:21980418

  11. Inhibition of HIV Virus by Neutralizing Vhh Attached to Dual Functional Liposomes Encapsulating Dapivirine.

    PubMed

    Wang, Scarlet Xiaoyan; Michiels, Johan; Ariën, Kevin K; New, Roger; Vanham, Guido; Roitt, Ivan

    2016-12-01

    efficacy in reducing viral replication in vitro. Thus, dual function liposomes may lead to a novel strategy for the prophylaxis of HIV/AIDS by combining the neutralizing activity of Vhh with antiviral effects of high drug concentrations.

  12. Inhibition of HIV Virus by Neutralizing Vhh Attached to Dual Functional Liposomes Encapsulating Dapivirine

    NASA Astrophysics Data System (ADS)

    Wang, Scarlet Xiaoyan; Michiels, Johan; Ariën, Kevin K.; New, Roger; Vanham, Guido; Roitt, Ivan

    2016-07-01

    efficacy in reducing viral replication in vitro. Thus, dual function liposomes may lead to a novel strategy for the prophylaxis of HIV/AIDS by combining the neutralizing activity of Vhh with antiviral effects of high drug concentrations.

  13. Functional Properties of the Mitochondrial Carrier System.

    PubMed

    Taylor, Eric B

    2017-09-01

    The mitochondrial carrier system (MCS) transports small molecules between mitochondria and the cytoplasm. It is integral to the core mitochondrial function to regulate cellular chemistry by metabolism. The mammalian MCS comprises the transporters of the 53-member canonical SLC25A family and a lesser number of identified noncanonical transporters. The recent discovery and investigations of the mitochondrial pyruvate carrier (MPC) illustrate the diverse effects a single mitochondrial carrier may exert on cellular function. However, the transport selectivities of many carriers remain unknown, and most have not been functionally investigated in mammalian cells. The mechanisms coordinating their function as a unified system remain undefined. Increased accessibility to molecular genetic and metabolomic technologies now greatly enables investigation of the MCS. Continued investigation of the MCS may reveal how mitochondria encode complex regulatory information within chemical thermodynamic gradients. This understanding may enable precision modulation of cellular chemistry to counteract the dysmetabolism inherent in disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. State of charge modeling of lithium-ion batteries using dual exponential functions

    NASA Astrophysics Data System (ADS)

    Kuo, Ting-Jung; Lee, Kung-Yen; Huang, Chien-Kang; Chen, Jau-Horng; Chiu, Wei-Li; Huang, Chih-Fang; Wu, Shuen-De

    2016-05-01

    A mathematical model is developed by fitting the discharging curve of LiFePO4 batteries and used to investigate the relationship between the state of charge and the closed-circuit voltage. The proposed mathematical model consists of dual exponential terms and a constant term which can fit the characteristics of dual equivalent RC circuits closely, representing a LiFePO4 battery. One exponential term presents the stable discharging behavior and the other one presents the unstable discharging behavior and the constant term presents the cut-off voltage.

  15. Peptides from Fish By-product Protein Hydrolysates and Its Functional Properties: an Overview.

    PubMed

    Zamora-Sillero, Juan; Gharsallaoui, Adem; Prentice, Carlos

    2018-04-01

    The inadequate management of fish processing waste or by-products is one of the major problems that fish industry has to face nowadays. The mismanagement of this raw material leads to economic loss and environmental problems. The demand for the use of these by-products has led to the development of several processes in order to recover biomolecules from fish by-products. An efficient way to add value to fish waste protein is protein hydrolysis. Protein hydrolysates improve the functional properties and allow the release of peptides of different sizes with several bioactivities such as antioxidant, antimicrobial, antihypertensive, anti-inflammatory, or antihyperglycemic among others. This paper reviews different methods for the production of protein hydrolysates as well as current research about several fish by-products protein hydrolysates bioactive properties, aiming the dual objective: adding value to these underutilized by-products and minimizing their negative impact on the environment.

  16. Function, Type, and Distribution of Teacher Questions in Dual-Language Preschool Read Alouds

    ERIC Educational Resources Information Center

    Gort, Mileidis; Pontier, Ryan W.; Sembiante, Sabrina F.

    2012-01-01

    This exploratory study investigated the nature and distribution of dual-language preschool teachers' questions across parallel Spanish- and English-medium read-aloud activities. The notions of comprehensible input (Krashen, 1985) and language output (Swain, 1985), along with a reciprocal interaction model of teaching (Cummins, 2000), guided our…

  17. Constructing Easily Iterated Functions with Interesting Properties

    ERIC Educational Resources Information Center

    Sprows, David J.

    2009-01-01

    A number of schools have recently introduced new courses dealing with various aspects of iteration theory or at least have found ways of including topics such as chaos and fractals in existing courses. In this note, we will consider a family of functions whose members are especially well suited to illustrate many of the concepts involved in these…

  18. Controlling plasma properties under differing degrees of electronegativity using odd harmonic dual frequency excitation

    NASA Astrophysics Data System (ADS)

    Gibson, Andrew R.; Gans, Timo

    2017-11-01

    The charged particle dynamics in low-pressure oxygen plasmas excited by odd harmonic dual frequency waveforms (low frequency of 13.56 MHz and high frequency of 40.68 MHz) are investigated using a one-dimensional numerical simulation in regimes of both low and high electronegativity. In the low electronegativity regime, the time and space averaged electron and negative ion densities are approximately equal and plasma sustainment is dominated by ionisation at the sheath expansion for all combinations of low and high frequency and the phase shift between them. In the high electronegativity regime, the negative ion density is a factor of 15-20 greater than the low electronegativity cases. In these cases, plasma sustainment is dominated by ionisation inside the bulk plasma and at the collapsing sheath edge when the contribution of the high frequency to the overall voltage waveform is low. As the high frequency component contribution to the waveform increases, sheath expansion ionisation begins to dominate. It is found that the control of the average voltage drop across the plasma sheath and the average ion flux to the powered electrode are similar in both regimes of electronegativity, despite the differing electron dynamics using the considered dual frequency approach. This offers potential for similar control of ion dynamics under a range of process conditions, independent of the electronegativity. This is in contrast to ion control offered by electrically asymmetric waveforms where the relationship between the ion flux and ion bombardment energy is dependent upon the electronegativity.

  19. Functional analysis of liverworts in dual symbiosis with Glomeromycota and Mucoromycotina fungi under a simulated Palaeozoic CO2 decline

    PubMed Central

    Field, Katie J; Rimington, William R; Bidartondo, Martin I; Allinson, Kate E; Beerling, David J; Cameron, Duncan D; Duckett, Jeffrey G; Leake, Jonathan R; Pressel, Silvia

    2016-01-01

    Most land plants form mutualistic associations with arbuscular mycorrhizal fungi of the Glomeromycota, but recent studies have found that ancient plant lineages form mutualisms with Mucoromycotina fungi. Simultaneous associations with both fungal lineages have now been found in some plants, necessitating studies to understand the functional and evolutionary significance of these tripartite associations for the first time. We investigate the physiology and cytology of dual fungal symbioses in the early-diverging liverworts Allisonia and Neohodgsonia at modern and Palaeozoic-like elevated atmospheric CO2 concentrations under which they are thought to have evolved. We found enhanced carbon cost to liverworts with simultaneous Mucoromycotina and Glomeromycota associations, greater nutrient gain compared with those symbiotic with only one fungal group in previous experiments and contrasting responses to atmospheric CO2 among liverwort–fungal symbioses. In liverwort–Mucoromycotina symbioses, there is increased P-for-C and N-for-C exchange efficiency at 440 p.p.m. compared with 1500 p.p.m. CO2. In liverwort–Glomeromycota symbioses, P-for-C exchange is lower at ambient CO2 compared with elevated CO2. No characteristic cytologies of dual symbiosis were identified. We provide evidence of a distinct physiological niche for plant symbioses with Mucoromycotina fungi, giving novel insight into why dual symbioses with Mucoromycotina and Glomeromycota fungi persist to the present day. PMID:26613340

  20. Quinoa (Chenopodium quinoa Willd.): composition, chemistry, nutritional, and functional properties.

    PubMed

    Abugoch James, Lilian E

    2009-01-01

    Quinoa (Chenopodium quinoa Willd.), which is considered a pseudocereal or pseudograin, has been recognized as a complete food due to its protein quality. It has remarkable nutritional properties; not only from its protein content (15%) but also from its great amino acid balance. It is an important source of minerals and vitamins, and has also been found to contain compounds like polyphenols, phytosterols, and flavonoids with possible nutraceutical benefits. It has some functional (technological) properties like solubility, water-holding capacity (WHC), gelation, emulsifying, and foaming that allow diversified uses. Besides, it has been considered an oil crop, with an interesting proportion of omega-6 and a notable vitamin E content. Quinoa starch has physicochemical properties (such as viscosity, freeze stability) which give it functional properties with novel uses. Quinoa has a high nutritional value and has recently been used as a novel functional food because of all these properties; it is a promising alternative cultivar.

  1. The photoluminescence, drug delivery and imaging properties of multifunctional Eu3+/Gd3+ dual-doped hydroxyapatite nanorods.

    PubMed

    Chen, Feng; Huang, Peng; Zhu, Ying-Jie; Wu, Jin; Zhang, Chun-Lei; Cui, Da-Xiang

    2011-12-01

    The design and synthesis of multifunctional systems with high biocompatibility are very significant for the future of clinical applications. Herein, we report a microwave-assisted rapid synthesis of multifunctional Eu(3+)/Gd(3+) dual-doped hydroxyapatite (HAp) nanorods, and the photoluminescence (PL), drug delivery and in vivo imaging of as-prepared Eu(3+)/Gd(3+) doped HAp nanorods. The photoluminescent and magnetic multifunctions of HAp nanorods are realized by the dual-doping with Eu(3+) and Gd(3+). The PL intensity of doped HAp nanorods can be adjusted by varying Eu(3+) and Gd(3+) concentrations. The magnetization of doped HAp nanorods increases with the concentration of doped Gd(3+). The as-prepared Eu(3+)/Gd(3+)-doped HAp nanorods exhibit inappreciable toxicity to the cells in vitro. More importantly, the Eu(3+)/Gd(3+)-doped HAp nanorods show a high drug adsorption capacity and sustained drug release using ibuprofen as a model drug, and the drug release is governed by a diffusion process. Furthermore, the noninvasive visualization of nude mice with subcutaneous injection indicates that the Eu(3+)/Gd(3+)-doped HAp nanorods with the photoluminescent function are suitable for in vivo imaging. In vitro and in vivo imaging tests indicate that Eu(3+)/Gd(3+)-doped HAp nanorods have a potential in applications such as a multiple-model imaging agent for magnetic resonance (MR) imaging, photoluminescence imaging and computed tomography (CT) imaging. The Eu(3+)/Gd(3+) dual-doped HAp nanorods are promising for applications in the biomedical fields such as multifunctional drug delivery systems with imaging guidance. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Properties of Diamond-Like Carbon Films Synthesized by Dual-Target Unbalanced Magnetron Sputtering

    NASA Astrophysics Data System (ADS)

    Liu, Cui; Li, Guo-Qing; Gou, Wei; Mu, Zong-Xin; Zhang, Cheng-Wu

    2004-11-01

    Smooth, dense and uniform diamond-like carbon films (DLC films) for industrial applications have successfully been prepared by dual-target unbalanced magnetron sputtering and the DLC characteristics of the films are confirmed by Raman spectra. It is found that the sputtering current of target plays an important role in the DLC film deposition. Deposition rate of 3.5 μm/h is obtained by using the sputtering current of 30 A. The friction coefficient of the films is 0.2-0.225 measured by using a pin-on-disc microtribometer. The structure of the films tends to have a growth of sp3 bonds content at high sputtering current. The compressive residual stress in the films increases with the increasing sputtering current of the target.

  3. Soil properties, soil functions and soil security

    NASA Astrophysics Data System (ADS)

    Poggio, Laura; Gimona, Alessandro

    2017-04-01

    Soil plays a crucial role in the ecosystem functioning such as food production, capture and storage of water, carbon and nutrients and in the realisation of a number of UN Sustainable Developments Goals. In this work we present an approach to spatially and jointly assess the multiple contributions of soil to the delivery of ecosystem services within multiple land-use system. We focussed on the modelling of the impact of soil on sediment retention, carbon storage, storing and filtering of nutrients, habitat for soil organisms and water regulation, taking into account examples of land use and climate scenarios. Simplified models were used for the single components. Spatialised Bayesian Belief networks were used for the jointly assessment and mapping of soil contribution to multiple land use and ecosystem services. We integrated continuous 3D soil information derived from digital soil mapping approaches covering the whole of mainland Scotland, excluding the Northern Islands. Uncertainty was accounted for and propagated across the whole process. The Scottish test case highlights the differences in roles between mineral and organic soils and provides an example of integrated study assessing the contributions of soil. The results show the importance of the multi-functional analysis of the contribution of soils to the ecosystem service delivery and UN SDGs.

  4. Estimating soil hydraulic properties from soil moisture time series by inversion of a dual-permeability model

    NASA Astrophysics Data System (ADS)

    Dalla Valle, Nicolas; Wutzler, Thomas; Meyer, Stefanie; Potthast, Karin; Michalzik, Beate

    2017-04-01

    Dual-permeability type models are widely used to simulate water fluxes and solute transport in structured soils. These models contain two spatially overlapping flow domains with different parameterizations or even entirely different conceptual descriptions of flow processes. They are usually able to capture preferential flow phenomena, but a large set of parameters is needed, which are very laborious to obtain or cannot be measured at all. Therefore, model inversions are often used to derive the necessary parameters. Although these require sufficient input data themselves, they can use measurements of state variables instead, which are often easier to obtain and can be monitored by automated measurement systems. In this work we show a method to estimate soil hydraulic parameters from high frequency soil moisture time series data gathered at two different measurement depths by inversion of a simple one dimensional dual-permeability model. The model uses an advection equation based on the kinematic wave theory to describe the flow in the fracture domain and a Richards equation for the flow in the matrix domain. The soil moisture time series data were measured in mesocosms during sprinkling experiments. The inversion consists of three consecutive steps: First, the parameters of the water retention function were assessed using vertical soil moisture profiles in hydraulic equilibrium. This was done using two different exponential retention functions and the Campbell function. Second, the soil sorptivity and diffusivity functions were estimated from Boltzmann-transformed soil moisture data, which allowed the calculation of the hydraulic conductivity function. Third, the parameters governing flow in the fracture domain were determined using the whole soil moisture time series. The resulting retention functions were within the range of values predicted by pedotransfer functions apart from very dry conditions, where all retention functions predicted lower matrix potentials

  5. RNAdualPF: software to compute the dual partition function with sample applications in molecular evolution theory.

    PubMed

    Garcia-Martin, Juan Antonio; Bayegan, Amir H; Dotu, Ivan; Clote, Peter

    2016-10-19

    RNA inverse folding is the problem of finding one or more sequences that fold into a user-specified target structure s 0 , i.e. whose minimum free energy secondary structure is identical to the target s 0 . Here we consider the ensemble of all RNA sequences that have low free energy with respect to a given target s 0 . We introduce the program RNAdualPF, which computes the dual partition function Z ∗ , defined as the sum of Boltzmann factors exp(-E(a,s 0 )/RT) of all RNA nucleotide sequences a compatible with target structure s 0 . Using RNAdualPF, we efficiently sample RNA sequences that approximately fold into s 0 , where additionally the user can specify IUPAC sequence constraints at certain positions, and whether to include dangles (energy terms for stacked, single-stranded nucleotides). Moreover, since we also compute the dual partition function Z ∗ (k) over all sequences having GC-content k, the user can require that all sampled sequences have a precise, specified GC-content. Using Z ∗ , we compute the dual expected energy 〈E ∗ 〉, and use it to show that natural RNAs from the Rfam 12.0 database have higher minimum free energy than expected, thus suggesting that functional RNAs are under evolutionary pressure to be only marginally thermodynamically stable. We show that C. elegans precursor microRNA (pre-miRNA) is significantly non-robust with respect to mutations, by comparing the robustness of each wild type pre-miRNA sequence with 2000 [resp. 500] sequences of the same GC-content generated by RNAdualPF, which approximately [resp. exactly] fold into the wild type target structure. We confirm and strengthen earlier findings that precursor microRNAs and bacterial small noncoding RNAs display plasticity, a measure of structural diversity. We describe RNAdualPF, which rapidly computes the dual partition function Z ∗ and samples sequences having low energy with respect to a target structure, allowing sequence constraints and specified GC

  6. Walking in School-Aged Children in a Dual-Task Paradigm Is Related to Age But Not to Cognition, Motor Behavior, Injuries, or Psychosocial Functioning

    PubMed Central

    Hagmann-von Arx, Priska; Manicolo, Olivia; Lemola, Sakari; Grob, Alexander

    2016-01-01

    Age-dependent gait characteristics and associations with cognition, motor behavior, injuries, and psychosocial functioning were investigated in 138 typically developing children aged 6.7–13.2 years (M = 10.0 years). Gait velocity, normalized velocity, and variability were measured using the walkway system GAITRite without an additional task (single task) and while performing a motor or cognitive task (dual task). Assessment of children’s cognition included tests for intelligence and executive functions; parents reported on their child’s motor behavior, injuries, and psychosocial functioning. Gait variability (an index of gait regularity) decreased with increasing age in both single- and dual-task walking. Dual-task gait decrements were stronger when children walked in the motor compared to the cognitive dual-task condition and decreased with increasing age in both dual-task conditions. Gait alterations from single- to dual-task conditions were not related to children’s cognition, motor behavior, injuries, or psychosocial functioning. PMID:27014158

  7. Dual-function photonic integrated circuit for frequency octo-tupling or single-side-band modulation.

    PubMed

    Hasan, Mehedi; Maldonado-Basilio, Ramón; Hall, Trevor J

    2015-06-01

    A dual-function photonic integrated circuit for microwave photonic applications is proposed. The circuit consists of four linear electro-optic phase modulators connected optically in parallel within a generalized Mach-Zehnder interferometer architecture. The photonic circuit is arranged to have two separate output ports. A first port provides frequency up-conversion of a microwave signal from the electrical to the optical domain; equivalently single-side-band modulation. A second port provides tunable millimeter wave carriers by frequency octo-tupling of an appropriate amplitude RF carrier. The circuit exploits the intrinsic relative phases between the ports of multi-mode interference couplers to provide substantially all the static optical phases needed. The operation of the proposed dual-function photonic integrated circuit is verified by computer simulations. The performance of the frequency octo-tupling and up-conversion functions is analyzed in terms of the electrical signal to harmonic distortion ratio and the optical single side band to unwanted harmonics ratio, respectively.

  8. Explanation and inference: mechanistic and functional explanations guide property generalization.

    PubMed

    Lombrozo, Tania; Gwynne, Nicholas Z

    2014-01-01

    The ability to generalize from the known to the unknown is central to learning and inference. Two experiments explore the relationship between how a property is explained and how that property is generalized to novel species and artifacts. The experiments contrast the consequences of explaining a property mechanistically, by appeal to parts and processes, with the consequences of explaining the property functionally, by appeal to functions and goals. The findings suggest that properties that are explained functionally are more likely to be generalized on the basis of shared functions, with a weaker relationship between mechanistic explanations and generalization on the basis of shared parts and processes. The influence of explanation type on generalization holds even though all participants are provided with the same mechanistic and functional information, and whether an explanation type is freely generated (Experiment 1), experimentally provided (Experiment 2), or experimentally induced (Experiment 2). The experiments also demonstrate that explanations and generalizations of a particular type (mechanistic or functional) can be experimentally induced by providing sample explanations of that type, with a comparable effect when the sample explanations come from the same domain or from a different domains. These results suggest that explanations serve as a guide to generalization, and contribute to a growing body of work supporting the value of distinguishing mechanistic and functional explanations.

  9. Functional Properties and Genomics of Glucose Transporters

    PubMed Central

    Zhao, Feng-Qi; Keating, Aileen F

    2007-01-01

    Glucose is the major energy source for mammalian cells as well as an important substrate for protein and lipid synthesis. Mammalian cells take up glucose from extracellular fluid into the cell through two families of structurallyrelated glucose transporters. The facilitative glucose transporter family (solute carriers SLC2A, protein symbol GLUT) mediates a bidirectional and energy-independent process of glucose transport in most tissues and cells, while the NaM+/glucose cotransporter family (solute carriers SLC5A, protein symbol SGLT) mediates an active, Na+-linked transport process against an electrochemical gradient. The GLUT family consists of thirteen members (GLUT1-12 and HMIT). Phylogenetically, the members of the GLUT family are split into three classes based on protein similarities. Up to now, at least six members of the SGLT family have been cloned (SGLT1-6). In this review, we report both the genomic structure and function of each transporter as well as intra-species comparative genomic analysis of some of these transporters. The affinity for glucose and transport kinetics of each transporter differs and ranges from 0.2 to 17mM. The ability of each protein to transport alternative substrates also differs and includes substrates such as fructose and galactose. In addition, the tissue distribution pattern varies between species. There are different regulation mechanisms of these transporters. Characterization of transcriptional control of some of the gene promoters has been investigated and alternative promoter usage to generate different protein isoforms has been demonstrated. We also introduce some pathophysiological roles of these transporters in human. PMID:18660845

  10. Molecular Docking and Prediction of Pharmacokinetic Properties of Dual Mechanism Drugs that Block MAO-B and Adenosine A2A Receptors for the Treatment of Parkinson's Disease

    PubMed Central

    Azam, Faizul; Madi, Arwa M.; Ali, Hamed I.

    2012-01-01

    Monoamine oxidase B (MAO-B) inhibitory potential of adenosine A2A receptor (AA2AR) antagonists has raised the possibility of designing dual-target–directed drugs that may provide enhanced symptomatic relief and that may also slow the progression of Parkinson's disease (PD) by protecting against further neurodegeneration. To explain the dual inhibition of MAO-B and AA2AR at the molecular level, molecular docking technique was employed. Lamarckian genetic algorithm methodology was used for flexible ligand docking studies. A good correlation (R2= 0.524 and 0.627 for MAO-B and AA2AR, respectively) was established between docking predicted and experimental Ki values, which confirms that the molecular docking approach is reliable to study the mechanism of dual interaction of caffeinyl analogs with MAO-B and AA2AR. Parameters for Lipinski's “Rule-of-Five” were also calculated to estimate the pharmacokinetic properties of dual-target–directed drugs where both MAO-B inhibition and AA2AR antagonism exhibited a positive correlation with calculated LogP having a correlation coefficient R2 of 0.535 and 0.607, respectively. These results provide some beneficial clues in structural modification for designing new inhibitors as dual-target–directed drugs with desired pharmacokinetic properties for the treatment of PD. PMID:23112538

  11. A method for surface topography measurement using a new focus function based on dual-tree complex wavelet transform

    NASA Astrophysics Data System (ADS)

    Li, Shimiao; Guo, Tong; Yuan, Lin; Chen, Jinping

    2018-01-01

    Surface topography measurement is an important tool widely used in many fields to determine the characteristics and functionality of a part or material. Among existing methods for this purpose, the focus variation method has proved high performance particularly in large slope scenarios. However, its performance depends largely on the effectiveness of focus function. This paper presents a method for surface topography measurement using a new focus measurement function based on dual-tree complex wavelet transform. Experiments are conducted on simulated defocused images to prove its high performance in comparison with other traditional approaches. The results showed that the new algorithm has better unimodality and sharpness. The method was also verified by measuring a MEMS micro resonator structure.

  12. Structure-function-property-design interplay in biopolymers: spider silk.

    PubMed

    Tokareva, Olena; Jacobsen, Matthew; Buehler, Markus; Wong, Joyce; Kaplan, David L

    2014-04-01

    Spider silks have been a focus of research for almost two decades due to their outstanding mechanical and biophysical properties. Recent advances in genetic engineering have led to the synthesis of recombinant spider silks, thus helping to unravel a fundamental understanding of structure-function-property relationships. The relationships between molecular composition, secondary structures and mechanical properties found in different types of spider silks are described, along with a discussion of artificial spinning of these proteins and their bioapplications, including the role of silks in biomineralization and fabrication of biomaterials with controlled properties. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  13. Structure-Function-Property-Design Interplay in Biopolymers: Spider Silk

    PubMed Central

    Tokareva, Olena; Jacobsen, Matthew; Buehler, Markus; Wong, Joyce; Kaplan, David L.

    2013-01-01

    Spider silks have been a focus of research for almost two decades due to their outstanding mechanical and biophysical properties. Recent advances in genetic engineering have led to the synthesis of recombinant spider silks, thus helping to unravel a fundamental understanding of structure-function-property relationships. The relationships between molecular composition, secondary structures, and mechanical properties found in different types of spider silks are described, along with a discussion of artificial spinning of these proteins and their bioapplications, including the role of silks in biomineralization and fabrication of biomaterials with controlled properties. PMID:23962644

  14. Canola Proteins for Human Consumption: Extraction, Profile, and Functional Properties

    PubMed Central

    Tan, Siong H; Mailer, Rodney J; Blanchard, Christopher L; Agboola, Samson O

    2011-01-01

    Canola protein isolate has been suggested as an alternative to other proteins for human food use due to a balanced amino acid profile and potential functional properties such as emulsifying, foaming, and gelling abilities. This is, therefore, a review of the studies on the utilization of canola protein in human food, comprising the extraction processes for protein isolates and fractions, the molecular character of the extracted proteins, as well as their food functional properties. A majority of studies were based on proteins extracted from the meal using alkaline solution, presumably due to its high nitrogen yield, followed by those utilizing salt extraction combined with ultrafiltration. Characteristics of canola and its predecessor rapeseed protein fractions such as nitrogen yield, molecular weight profile, isoelectric point, solubility, and thermal properties have been reported and were found to be largely related to the extraction methods. However, very little research has been carried out on the hydrophobicity and structure profiles of the protein extracts that are highly relevant to a proper understanding of food functional properties. Alkaline extracts were generally not very suitable as functional ingredients and contradictory results about many of the measured properties of canola proteins, especially their emulsification tendencies, have also been documented. Further research into improved extraction methods is recommended, as is a more systematic approach to the measurement of desired food functional properties for valid comparison between studies. PMID:21535703

  15. Dynamic PET of human liver inflammation: impact of kinetic modeling with optimization-derived dual-blood input function.

    PubMed

    Wang, Guobao; Corwin, Michael T; Olson, Kristin A; Badawi, Ramsey D; Sarkar, Souvik

    2018-05-30

    The hallmark of nonalcoholic steatohepatitis is hepatocellular inflammation and injury in the setting of hepatic steatosis. Recent work has indicated that dynamic 18F-FDG PET with kinetic modeling has the potential to assess hepatic inflammation noninvasively, while static FDG-PET did not show a promise. Because the liver has dual blood supplies, kinetic modeling of dynamic liver PET data is challenging in human studies. The objective of this study is to evaluate and identify a dual-input kinetic modeling approach for dynamic FDG-PET of human liver inflammation. Fourteen human patients with nonalcoholic fatty liver disease were included in the study. Each patient underwent one-hour dynamic FDG-PET/CT scan and had liver biopsy within six weeks. Three models were tested for kinetic analysis: traditional two-tissue compartmental model with an image-derived single-blood input function (SBIF), model with population-based dual-blood input function (DBIF), and modified model with optimization-derived DBIF through a joint estimation framework. The three models were compared using Akaike information criterion (AIC), F test and histopathologic inflammation reference. The results showed that the optimization-derived DBIF model improved the fitting of liver time activity curves and achieved lower AIC values and higher F values than the SBIF and population-based DBIF models in all patients. The optimization-derived model significantly increased FDG K1 estimates by 101% and 27% as compared with traditional SBIF and population-based DBIF. K1 by the optimization-derived model was significantly associated with histopathologic grades of liver inflammation while the other two models did not provide a statistical significance. In conclusion, modeling of DBIF is critical for kinetic analysis of dynamic liver FDG-PET data in human studies. The optimization-derived DBIF model is more appropriate than SBIF and population-based DBIF for dynamic FDG-PET of liver inflammation. © 2018

  16. Morphology and Gas-Sensing Properties of Tin Oxide Foams with Dual Pore Structure

    NASA Astrophysics Data System (ADS)

    Nam, Kyungju; Kim, Hyeong-Gwan; Choi, Hyelim; Park, Hyeji; Kang, Jin Soo; Sung, Yung-Eun; Lee, Hee Chul; Choe, Heeman

    2017-06-01

    Tin oxide is a commonly used gas-sensing material, which can be applied as an n- or p-type gas sensor. To improve the gas-sensing performance of tin oxide, we successfully synthesized tin oxide foam via an ice-templating or freeze-casting method. The tin oxide foam samples showed different morphological features depending on the major processing parameters, which include sintering temperature, sintering time, and the amount of added powder. Based on scanning electron microscopy images, we could identify dual pore structure of tin oxide foam containing `wall' pores ranging from 5.3 μm to 10.7 μm, as well as smaller secondary pores (a few micrometers in size) on the wall surfaces. Gas-sensing performance tests for the synthesized tin oxide foams reveal a sensitivity of 13.1, a response time of 192 s, and a recovery time of 160 s at an ethanol gas concentration of 60 ppm at 300°C. This is a remarkable result given that it showed p-type semiconductor behavior and was used without the addition of any catalyst.

  17. The Effect of Niobium Microalloying on Processing and Application Properties of Dual Phase Steel

    NASA Astrophysics Data System (ADS)

    Mohrbacher, Hardy

    Dual phase steel is widely used in today's car body manufacturing. Its characteristics of high n-value and good elongation (A80) are the basis of good press formability. However, practical experience has shown unexpected failure in forming operations where tight bending, stretch flanging or hole expansion are predominant. The inhomogeneous microstructure of soft ferrite and hard martensite in combination with highly localized straining is the origin of these problems. Furthermore, weldability and delayed cracking have been experienced to cause problems in ultra-high strength DP steel. Refinement and homogenization of the two-phase microstructure as well as lowering of the carbon content have been identified as remedies to the mentioned problems. However, mill processing of DP steel with reduced carbon content is more difficult especially for the higher strength levels. Niobium microalloying proved to be very effective in increasing the processing window of low-carbon DP steels besides of its natural effect of refining the microstructure. Meanwhile the production of niobium microalloyed DP steel has been established in several markets including China. The paper details the fundamentals, demonstrates respective production concepts and presents examples of application of Nb-microalloyed DP steels.

  18. Properties of intermodal transfer after dual visuo- and auditory-motor adaptation.

    PubMed

    Schmitz, Gerd; Bock, Otmar L

    2017-10-01

    Previous work documented that sensorimotor adaptation transfers between sensory modalities: When subjects adapt with one arm to a visuomotor distortion while responding to visual targets, they also appear to be adapted when they are subsequently tested with auditory targets. Vice versa, when they adapt to an auditory-motor distortion while pointing to auditory targets, they appear to be adapted when they are subsequently tested with visual targets. Therefore, it was concluded that visuomotor as well as auditory-motor adaptation use the same adaptation mechanism. Furthermore, it has been proposed that sensory information from the trained modality is weighted larger than sensory information from an untrained one, because transfer between sensory modalities is incomplete. The present study tested these hypotheses for dual arm adaptation. One arm adapted to an auditory-motor distortion and the other either to an opposite directed auditory-motor or visuomotor distortion. We found that both arms adapted significantly. However, compared to reference data on single arm adaptation, adaptation in the dominant arm was reduced indicating interference from the non-dominant to the dominant arm. We further found that arm-specific aftereffects of adaptation, which reflect recalibration of sensorimotor transformation rules, were stronger or equally strong when targets were presented in the previously adapted compared to the non-adapted sensory modality, even when one arm adapted visually and the other auditorily. The findings are discussed with respect to a recently published schematic model on sensorimotor adaptation. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. High-frequency dual mode pulsed wave Doppler imaging for monitoring the functional regeneration of adult zebrafish hearts

    PubMed Central

    Kang, Bong Jin; Park, Jinhyoung; Kim, Jieun; Kim, Hyung Ham; Lee, Changyang; Hwang, Jae Youn; Lien, Ching-Ling; Shung, K. Kirk

    2015-01-01

    Adult zebrafish is a well-known small animal model for studying heart regeneration. Although the regeneration of scars made by resecting the ventricular apex has been visualized with histological methods, there is no adequate imaging tool for tracking the functional recovery of the damaged heart. For this reason, high-frequency Doppler echocardiography using dual mode pulsed wave Doppler, which provides both tissue Doppler (TD) and Doppler flow in a same cardiac cycle, is developed with a 30 MHz high-frequency array ultrasound imaging system. Phantom studies show that the Doppler flow mode of the dual mode is capable of measuring the flow velocity from 0.1 to 15 cm s−1 with high accuracy (p-value = 0.974 > 0.05). In the in vivo study of zebrafish, both TD and Doppler flow signals were simultaneously obtained from the zebrafish heart for the first time, and the synchronized valve motions with the blood flow signals were identified. In the longitudinal study on the zebrafish heart regeneration, the parameters for diagnosing the diastolic dysfunction, for example, E/Em < 10, E/A < 0.14 for wild-type zebrafish, were measured, and the type of diastolic dysfunction caused by the amputation was found to be similar to the restrictive filling. The diastolic function was fully recovered within four weeks post-amputation. PMID:25505135

  20. Current-induced alternating reversed dual-echo-steady-state for joint estimation of tissue relaxation and electrical properties.

    PubMed

    Lee, Hyunyeol; Sohn, Chul-Ho; Park, Jaeseok

    2017-07-01

    To develop a current-induced, alternating reversed dual-echo-steady-state-based magnetic resonance electrical impedance tomography for joint estimation of tissue relaxation and electrical properties. The proposed method reverses the readout gradient configuration of conventional, in which steady-state-free-precession (SSFP)-ECHO is produced earlier than SSFP-free-induction-decay (FID) while alternating current pulses are applied in between the two SSFPs to secure high sensitivity of SSFP-FID to injection current. Additionally, alternating reversed dual-echo-steady-state signals are modulated by employing variable flip angles over two orthogonal injections of current pulses. Ratiometric signal models are analytically constructed, from which T 1 , T 2 , and current-induced B z are jointly estimated by solving a nonlinear inverse problem for conductivity reconstruction. Numerical simulations and experimental studies are performed to investigate the feasibility of the proposed method in estimating relaxation parameters and conductivity. The proposed method, if compared with conventional magnetic resonance electrical impedance tomography, enables rapid data acquisition and simultaneous estimation of T 1 , T 2 , and current-induced B z , yielding a comparable level of signal-to-noise ratio in the parameter estimates while retaining a relative conductivity contrast. We successfully demonstrated the feasibility of the proposed method in jointly estimating tissue relaxation parameters as well as conductivity distributions. It can be a promising, rapid imaging strategy for quantitative conductivity estimation. Magn Reson Med 78:107-120, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  1. Effect of adding powder on joint properties of laser penetration welding for dual phase steel and aluminum alloy

    NASA Astrophysics Data System (ADS)

    Zhou, D. W.; Liu, J. S.; Lu, Y. Z.; Xu, S. H.

    2017-09-01

    The experiments of laser penetration welding for dual phase steel and aluminum alloy were carried out, and the effect of adding Mn or Si powder on mechanical properties and microstructure of the weld was investigated. Some defects, such as spatter, inclusion, cracks and softening in heat affected zone (HAZ), can be avoided in welding joints, and the increased penetration depth is obtained by adding Mn or Si powder. The average tensile-shear strength of Si-added joint is 3.84% higher than that of Mn-added joint, and the strength of both joints exceeds that of no-added joint. In the case of adding Mn powder, small amount of liquid Al is mixed into steel molten pool, and the Al content increases in both sides of the weld, which leads to the increased weld width in aluminum molten pool. Thus, transverse area increases in jointing steel to aluminum, which is significant for the improved tensile-shear strength of joints. As far as adding Si powder is concerned, it is not the case, the enhancement of the joint properties benefits from improvement of metallurgical reaction.

  2. Effect of a dual-task net-step exercise on cognitive and gait function in older adults.

    PubMed

    Kitazawa, Kazutoshi; Showa, Satoko; Hiraoka, Akira; Fushiki, Yasuhiro; Sakauchi, Humio; Mori, Mitsuru

    2015-01-01

    Participation in generally recommended aerobics or strength exercises may be challenging for older adults. Therefore, it is necessary to consider the types and levels of physical activities suited for them to improve their cognitive and gait function and adherence to exercise programs. This has prompted efforts to identify exercises that require less physical strength and frequency of performance, while still offering cognitive and health benefits. Here, we aimed to assess the effect of a novel dual-task net-step exercise (NSE) performed once a week for 8 consecutive weeks on improvements in cognitive performance and gait function in an older population. In this pretest/posttest experimental case control study, 60 healthy older adults (mean age 76.4 years) were recruited from community-dwelling people and separated randomly into 2 groups: a dual-task NSE group and a control group. The NSE group was asked to walk across a net without stepping on the ropes or being caught in the net. Two computer panel-type cognitive functional assessments, the Touch-M and Touch Panel-Type Dementia Assessment Scale, were administered at baseline and after 8 weeks of intervention to determine the effects of NSE. Improvements in gait function were also evaluated using Timed Up and Go test scores. Mixed-effect models with repeated measures (group × time) (analysis of variance, F test) were used to test the effects of NSE. Adjustments were made for covariates including age and sex (analysis of covariance). The NSE group showed significant improvement in cognitive performance (6.8% change; total Touch-M score 5.4 points; P = .04) and gait performance (11.5% change; Timed Up and Go time -0.98 second; P < .001) over the 8-week period. In the control group, there was no significant improvement. This study shows that dual-task NSE is capable of improving cognitive and gait performance in healthy older adults. Our results indicate that NSE offers an option for a large segment of the older

  3. A novel method to calibrate DOI function of a PET detector with a dual-ended-scintillator readout

    SciTech Connect

    Shao Yiping; Yao Rutao; Ma Tianyu

    The detection of depth-of-interaction (DOI) is a critical detector capability to improve the PET spatial resolution uniformity across the field-of-view and will significantly enhance, in particular, small bore system performance for brain, breast, and small animal imaging. One promising technique of DOI detection is to use dual-ended-scintillator readout that uses two photon sensors to detect scintillation light from both ends of a scintillator array and estimate DOI based on the ratio of signals (similar to Anger logic). This approach needs a careful DOI function calibration to establish accurate relationship between DOI and signal ratios, and to recalibrate if the detectionmore » condition is shifted due to the drift of sensor gain, bias variations, or degraded optical coupling, etc. However, the current calibration method that uses coincident events to locate interaction positions inside a single scintillator crystal has severe drawbacks, such as complicated setup, long and repetitive measurements, and being prone to errors from various possible misalignments among the source and detector components. This method is also not practically suitable to calibrate multiple DOI functions of a crystal array. To solve these problems, a new method has been developed that requires only a uniform flood source to irradiate a crystal array without the need to locate the interaction positions, and calculates DOI functions based solely on the uniform probability distribution of interactions over DOI positions without knowledge or assumption of detector responses. Simulation and experiment have been studied to validate the new method, and the results show that the new method, with a simple setup and one single measurement, can provide consistent and accurate DOI functions for the entire array of multiple scintillator crystals. This will enable an accurate, simple, and practical DOI function calibration for the PET detectors based on the design of dual-ended-scintillator readout

  4. A novel method to calibrate DOI function of a PET detector with a dual-ended-scintillator readout.

    PubMed

    Shao, Yiping; Yao, Rutao; Ma, Tianyu

    2008-12-01

    The detection of depth-of-interaction (DOI) is a critical detector capability to improve the PET spatial resolution uniformity across the field-of-view and will significantly enhance, in particular, small bore system performance for brain, breast, and small animal imaging. One promising technique of DOI detection is to use dual-ended-scintillator readout that uses two photon sensors to detect scintillation light from both ends of a scintillator array and estimate DOI based on the ratio of signals (similar to Anger logic). This approach needs a careful DOI function calibration to establish accurate relationship between DOI and signal ratios, and to recalibrate if the detection condition is shifted due to the drift of sensor gain, bias variations, or degraded optical coupling, etc. However, the current calibration method that uses coincident events to locate interaction positions inside a single scintillator crystal has severe drawbacks, such as complicated setup, long and repetitive measurements, and being prone to errors from various possible misalignments among the source and detector components. This method is also not practically suitable to calibrate multiple DOI functions of a crystal array. To solve these problems, a new method has been developed that requires only a uniform flood source to irradiate a crystal array without the need to locate the interaction positions, and calculates DOI functions based solely on the uniform probability distribution of interactions over DOI positions without knowledge or assumption of detector responses. Simulation and experiment have been studied to validate the new method, and the results show that the new method, with a simple setup and one single measurement, can provide consistent and accurate DOI functions for the entire array of multiple scintillator crystals. This will enable an accurate, simple, and practical DOI function calibration for the PET detectors based on the design of dual-ended-scintillator readout. In

  5. Properties of the Magnitude Terms of Orthogonal Scaling Functions.

    PubMed

    Tay, Peter C; Havlicek, Joseph P; Acton, Scott T; Hossack, John A

    2010-09-01

    The spectrum of the convolution of two continuous functions can be determined as the continuous Fourier transform of the cross-correlation function. The same can be said about the spectrum of the convolution of two infinite discrete sequences, which can be determined as the discrete time Fourier transform of the cross-correlation function of the two sequences. In current digital signal processing, the spectrum of the contiuous Fourier transform and the discrete time Fourier transform are approximately determined by numerical integration or by densely taking the discrete Fourier transform. It has been shown that all three transforms share many analogous properties. In this paper we will show another useful property of determining the spectrum terms of the convolution of two finite length sequences by determining the discrete Fourier transform of the modified cross-correlation function. In addition, two properties of the magnitude terms of orthogonal wavelet scaling functions are developed. These properties are used as constraints for an exhaustive search to determine an robust lower bound on conjoint localization of orthogonal scaling functions.

  6. CD134/CD137 Dual Costimulation-Elicited IFN-γ Maximizes Effector T Cell Function but Limits Treg Expansion

    PubMed Central

    Rose, Marie-Clare St.; Taylor, Roslyn A.; Bandyopadhyay, Suman; Qui, Harry Z.; Hagymasi, Adam T.; Vella, Anthony T.; Adler, Adam J.

    2012-01-01

    T cell tolerance to tumor antigens represents a major hurdle in generating tumor immunity. Combined administration of agonistic monoclonal antibodies to the costimulatory receptors CD134 plus CD137 can program T cells responding to tolerogenic antigen to undergo expansion and effector T cell differentiation, and also elicits tumor immunity. Nevertheless, CD134 and CD137 agonists can also engage inhibitory immune components. To understand how immune stimulatory versus inhibitory components are regulated during CD134 plus CD137 dual costimulation, the current study utilized a model where dual costimulation programs T cells encountering a highly tolerogenic self-antigen to undergo effector differentiation. IFN-γ was found to play a pivotal role in maximizing the function of effector T cells while simultaneously limiting the expansion of CD4+CD25+Foxp3+ Tregs. In antigen-responding effector T cells, IFN-γ operates via a direct cell-intrinsic mechanism to cooperate with IL-2 to program maximal expression of granzyme B. Simultaneously, IFN-γ limits expression of the IL-2 receptor alpha chain (CD25) and IL-2 signaling through a mechanism that does not involve T-bet-mediated repression of IL-2. IFN-γ also limited CD25 and Foxp3 expression on bystanding CD4+Foxp3+ Tregs, and limited the potential of these Tregs to expand. These effects could not be explained by the ability of IFN-γ to limit IL-2 availability. Taken together, during dual costimulation IFN-γ interacts with IL-2 through distinct mechanisms to program maximal expression of effector molecules in antigen-responding T cells while simultaneously limiting Treg expansion. PMID:23295363

  7. Analysis of Genotoxic and Cytotoxic Responses Induced by Simulated Space Radiation Qualities by Use of Recombinant Bacteria Carrying a Dual-Function Dual-Reporter Construct

    NASA Astrophysics Data System (ADS)

    Baumstark-Khan, Christa; Hellweg, Christine; Zahoor, Ahmed; Testard, Isabelle; Reitz, Guenther

    Along with the long-term space exploration come various potential health risks due to unique physical factors of the space environment. Space radiation is one of the primary environmental hazards associated with space flight. In order to deal with space-related risk radiation exposure must be properly characterised and quantified, and biological effects of charged particles have to be analysed in ground based research, especially as astronauts are subjected to a differing radiation quality in space than they receive on Earth. For risk assessment, the mutagenic potential of the heavy ion component of the galactic cosmic radiation is of major concern for tumour induction as radiation late effects. The recombinant SWITCH test is based on TA1535 Salmonella typhimurium cells transformed with a dual-function dual-reporter vector harbouring (a) the genes for bioluminescence production from Photobacterium leiognathi under the control of a DNA-damage inducible promoter and (b) the gene for green fluorescent protein from the jellyfish Aequorea victoria under the control of a constitutive promoter. Suchlike genetically modified organism report on the presence of genotoxic conditions by dose dependent increase of bioluminescence induction and on the presence of cytotoxic conditions by dose dependent decrease in GFP fluorescence. By this, it is possible to analyse bacterial inactivation and mutation induction by ionizing radiation in parallel in the same cell within short time. Experiments with heavy ions have been performed with the SWITCH test at GANIL with the following accelerated heavy ions: 35 MeV/u (72 keV/µm) and 75 MeV/u (37 keV/µm) carbon, 95 MeV/u argon (377 keV/µm), 95 MeV/u neon (98 keV/µm), 75 MeV/u nickel (967 keV/µm) and 29 MeV/u lead (10238 keV/µm). The results obtained clearly show that the numbers of hits (particles per cm2 ) necessary to inactivate the bacteria (cytotoxicity) depend on LET. The higher the ionisation capacity of the accelerated ion, the

  8. Postnatal Experience Modulates Functional Properties of Mouse Olfactory Sensory Neurons

    PubMed Central

    He, Jiwei; Tian, Huikai; Lee, Anderson C.; Ma, Minghong

    2012-01-01

    Early experience considerably modulates the organization and function of all sensory systems. In the mammalian olfactory system, deprivation of the sensory inputs via neonatal, unilateral naris closure has been shown to induce structural, molecular, and functional changes from the olfactory epithelium to the olfactory bulb and cortex. However, it remains unknown how early experience shapes functional properties of individual olfactory sensory neurons (OSNs), the primary odor detectors in the nose. To address this question, we examined odorant response properties of mouse OSNs in both the closed and open nostril after four weeks of unilateral naris closure with age-matched untreated animals as control. Using patch-clamp technique on genetically-tagged OSNs with defined odorant receptors (ORs), we found that sensory deprivation increased the sensitivity of MOR23 neurons in the closed side while overexposure caused the opposite effect in the open side. We next analyzed the response properties including rise time, decay time, and adaptation induced by repeated stimulation in MOR23 and M71 neurons. Even though these two types of neurons showed distinct properties in dynamic range and response kinetics, sensory deprivation significantly slowed down the decay phase of odorant-induced transduction events in both types. Using western blotting and antibody staining, we confirmed upregulation of several signaling proteins in the closed side as compared with the open side. This study suggests that early experience modulates functional properties of OSNs, probably via modifying the signal transduction cascade. PMID:22703547

  9. Multi-scale invertigation of the relationship between the microstructure and mechanical properties in dual phase steels

    NASA Astrophysics Data System (ADS)

    Zhang, Fan

    Dual phase steel alloys belong to the first generation of advanced high strength steels that are widely used in the automotive industry to form body structure and closure panels of vehicles. A deeper understanding of the microstructural features, such as phase orientation and morphology are needed in order to establish their effect on the mechanical performance and to design a material with optimized attributes. In this work, our goal is to establish what kind of relationship exist between the mechanical properties and the microstructural representation of dual phase steels obtained from experimental observations. Microstructure in different specimens are characterized with advanced experimental techniques as optical microscopy, scanning electron microscopy, transmission electron microscopy, electron backscatter diffraction pattern, scanning probe microscopy, and nanoindentation. Nanoindentation, Vickers hardness and tensile testing are conducted to reveal a multi-scale mechanical performance on original material and also specimens under a variety combinations of temperatures, cooling rates, and rolling conditions. To quantify the single phase properties in each sample, an inverse method is adopted using experimental nanoindentation load-depth curves to obtain tensile stress-strain curves for each phase, and the inverse results were verified with the true stress-strain curves from tensile tests. This work also provides the insight on spatial phase distribution of different phases through a 2-point correlation statistical methodology and relate to material strength and formability. The microstructure information is correlated with the results of mechanical tests. The broken surfaces from tensile testing are analyzed to discover the fracture mechanism in relation to martensite morphology and distribuion. Viscoplastic self-consistent fast Fourier Transformation simulations is also used to compute efficiently the local and the homogenized viscoplastic response of the

  10. Design and Functional Validation of a Mechanism for Dual-Spinning CubeSats

    NASA Technical Reports Server (NTRS)

    Peters, Eric; Dave, Pratik; Kingsbury, Ryan; Marinan, Anne; Wise, Evan; Pong, Chris; Prinkey, Meghan; Cahoy, Kerri; Miller, David W.; Sklair, Devon

    2014-01-01

    The mission of the Micro-sized Microwave Atmospheric Satellite (MicroMAS) is to collect useful atmospheric images using a miniature passive microwave radiometer payload hosted on a low-cost CubeSat platform. In order to collect this data, the microwave radiometer payload must rotate to scan the ground-track perpendicular to the satellite's direction of travel. A custom motor assembly was developed to facilitate the rotation of the payload while allowing the spacecraft bus to remained fixed in the local-vertical, local-horizontal (LVLH) frame for increased pointing accuracy. This paper describes the mechanism used to enable this dual-spinning operation for CubeSats, and the lessons learned during the design, fabrication, integration, and testing phases of the mechanism's development lifecycle.

  11. Triple Antibiotic Polymer Nanofibers for Intracanal Drug Delivery: Effects on Dual Species Biofilm and Cell Function

    PubMed Central

    Pankajakshan, Divya; Albuquerque, Maria T.P.; Evans, Joshua D.; Kamocka, Malgorzata M.; Gregory, Richard L.; Bottino, Marco C.

    2016-01-01

    Introduction Root canal disinfection and the establishment of an intracanal microenvironment conducive to the proliferation/differentiation of stem cells play a significant role in regenerative endodontics. This study was designed to (1) investigate the antimicrobial efficacy of triple antibiotic–containing nanofibers against a dual-species biofilm and (2) evaluate the ability of dental pulp stem cells (DPSCs) to adhere to and proliferate on dentin upon nanofiber exposure. Methods Seven-day-old dual-species biofilm established on dentin specimens was exposed for 3 days to the following: saline (control), antibiotic-free nanofibers (control), and triple antibiotic–containing nanofibers or a saturated triple antibiotic paste (TAP) solution (50 mg/mL in phosphate buffer solution). Bacterial viability was assessed using the LIVE/DEAD assay (Molecular Probes, Inc, Eugene, OR) and confocal laser scanning microscopy. For cyto-compatibility studies, dentin specimens after nanofiber or TAP (1 g/mL in phosphate buffer solution) exposure were evaluated for cell adhesion and spreading by actin-phalloidin staining. DPSC proliferation was assessed on days 1, 3, and 7. Statistics were performed, and significance was set at the 5% level. Results Confocal laser scanning microscopy showed significant bacterial death upon antibiotic-containing nanofiber exposure, differing significantly (P < .05) from antibiotic-free fibers and the control (saline). DPSCs showed enhanced adhesion/spreading on dentin specimens treated with antibiotic-containing nanofibers when compared with its TAP counterparts. The DPSC proliferation rate was similar on days 1 and 3 in antibiotic-free nanofibers, triple antibiotic–containing nanofibers, and TAP-treated dentin. Proliferation was higher (9-fold) on dentin treated with antibiotic-containing nanofibers on day 7 compared with TAP. Conclusions Triple antibiotic–containing polymer nanofibers led to significant bacterial death, whereas they did not

  12. Triple Antibiotic Polymer Nanofibers for Intracanal Drug Delivery: Effects on Dual Species Biofilm and Cell Function.

    PubMed

    Pankajakshan, Divya; Albuquerque, Maria T P; Evans, Joshua D; Kamocka, Malgorzata M; Gregory, Richard L; Bottino, Marco C

    2016-10-01

    Root canal disinfection and the establishment of an intracanal microenvironment conducive to the proliferation/differentiation of stem cells play a significant role in regenerative endodontics. This study was designed to (1) investigate the antimicrobial efficacy of triple antibiotic-containing nanofibers against a dual-species biofilm and (2) evaluate the ability of dental pulp stem cells (DPSCs) to adhere to and proliferate on dentin upon nanofiber exposure. Seven-day-old dual-species biofilm established on dentin specimens was exposed for 3 days to the following: saline (control), antibiotic-free nanofibers (control), and triple antibiotic-containing nanofibers or a saturated triple antibiotic paste (TAP) solution (50 mg/mL in phosphate buffer solution). Bacterial viability was assessed using the LIVE/DEAD assay (Molecular Probes, Inc, Eugene, OR) and confocal laser scanning microscopy. For cytocompatibility studies, dentin specimens after nanofiber or TAP (1 g/mL in phosphate buffer solution) exposure were evaluated for cell adhesion and spreading by actin-phalloidin staining. DPSC proliferation was assessed on days 1, 3, and 7. Statistics were performed, and significance was set at the 5% level. Confocal laser scanning microscopy showed significant bacterial death upon antibiotic-containing nanofiber exposure, differing significantly (P < .05) from antibiotic-free fibers and the control (saline). DPSCs showed enhanced adhesion/spreading on dentin specimens treated with antibiotic-containing nanofibers when compared with its TAP counterparts. The DPSC proliferation rate was similar on days 1 and 3 in antibiotic-free nanofibers, triple antibiotic-containing nanofibers, and TAP-treated dentin. Proliferation was higher (9-fold) on dentin treated with antibiotic-containing nanofibers on day 7 compared with TAP. Triple antibiotic-containing polymer nanofibers led to significant bacterial death, whereas they did not affect DPSC attachment and proliferation on

  13. Dual-modality brain PET-CT image segmentation based on adaptive use of functional and anatomical information.

    PubMed

    Xia, Yong; Eberl, Stefan; Wen, Lingfeng; Fulham, Michael; Feng, David Dagan

    2012-01-01

    Dual medical imaging modalities, such as PET-CT, are now a routine component of clinical practice. Medical image segmentation methods, however, have generally only been applied to single modality images. In this paper, we propose the dual-modality image segmentation model to segment brain PET-CT images into gray matter, white matter and cerebrospinal fluid. This model converts PET-CT image segmentation into an optimization process controlled simultaneously by PET and CT voxel values and spatial constraints. It is innovative in the creation and application of the modality discriminatory power (MDP) coefficient as a weighting scheme to adaptively combine the functional (PET) and anatomical (CT) information on a voxel-by-voxel basis. Our approach relies upon allowing the modality with higher discriminatory power to play a more important role in the segmentation process. We compared the proposed approach to three other image segmentation strategies, including PET-only based segmentation, combination of the results of independent PET image segmentation and CT image segmentation, and simultaneous segmentation of joint PET and CT images without an adaptive weighting scheme. Our results in 21 clinical studies showed that our approach provides the most accurate and reliable segmentation for brain PET-CT images. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Dual therapeutic functions of F-5 fragment in burn wounds: preventing wound progression and promoting wound healing in pigs

    PubMed Central

    Bhatia, Ayesha; O’Brien, Kathryn; Chen, Mei; Wong, Alex; Garner, Warren; Woodley, David T.; Li, Wei

    2016-01-01

    Burn injuries are a leading cause of morbidity including prolonged hospitalization, disfigurement, and disability. Currently there is no Food and Drug Administration-approved burn therapeutics. A clinical distinction of burn injuries from other acute wounds is the event of the so-called secondary burn wound progression within the first week of the injury, in which a burn expands horizontally and vertically from its initial boundary to a larger area. Therefore, an effective therapeutics for burns should show dual abilities to prevent the burn wound progression and thereafter promote burn wound healing. Herein we report that topically applied F-5 fragment of heat shock protein-90α is a dual functional agent to promote burn wound healing in pigs. First, F-5 prevents burn wound progression by protecting the surrounding cells from undergoing heat-induced caspase 3 activation and apoptosis with increased Akt activation. Accordingly, F-5–treated burn and excision wounds show a marked decline in inflammation. Thereafter, F-5 accelerates burn wound healing by stimulating the keratinocyte migration-led reepithelialization, leading to wound closure. This study addresses a topical agent that is capable of preventing burn wound progression and accelerating burn wound healing. PMID:27382602

  15. Dual therapeutic functions of F-5 fragment in burn wounds: preventing wound progression and promoting wound healing in pigs.

    PubMed

    Bhatia, Ayesha; O'Brien, Kathryn; Chen, Mei; Wong, Alex; Garner, Warren; Woodley, David T; Li, Wei

    2016-01-01

    Burn injuries are a leading cause of morbidity including prolonged hospitalization, disfigurement, and disability. Currently there is no Food and Drug Administration-approved burn therapeutics. A clinical distinction of burn injuries from other acute wounds is the event of the so-called secondary burn wound progression within the first week of the injury, in which a burn expands horizontally and vertically from its initial boundary to a larger area. Therefore, an effective therapeutics for burns should show dual abilities to prevent the burn wound progression and thereafter promote burn wound healing. Herein we report that topically applied F-5 fragment of heat shock protein-90α is a dual functional agent to promote burn wound healing in pigs. First, F-5 prevents burn wound progression by protecting the surrounding cells from undergoing heat-induced caspase 3 activation and apoptosis with increased Akt activation. Accordingly, F-5-treated burn and excision wounds show a marked decline in inflammation. Thereafter, F-5 accelerates burn wound healing by stimulating the keratinocyte migration-led reepithelialization, leading to wound closure. This study addresses a topical agent that is capable of preventing burn wound progression and accelerating burn wound healing.

  16. Worsening respiratory function in mechanically ventilated intensive care patients: feasibility and value of xenon-enhanced dual energy CT.

    PubMed

    Hoegl, Sandra; Meinel, Felix G; Thieme, Sven F; Johnson, Thorsten R C; Eickelberg, Oliver; Zwissler, Bernhard; Nikolaou, Konstantin

    2013-03-01

    To evaluate the feasibility and incremental diagnostic value of xenon-enhanced dual-energy CT in mechanically ventilated intensive care patients with worsening respiratory function. The study was performed in 13 mechanically ventilated patients with severe pulmonary conditions (acute respiratory distress syndrome (ARDS), n=5; status post lung transplantation, n=5; other, n=3) and declining respiratory function. CT scans were performed using a dual-source CT scanner at an expiratory xenon concentration of 30%. Both ventilation images (Xe-DECT) and standard CT images were reconstructed from a single CT scan. Findings were recorded for Xe-DECT and standard CT images separately. Ventilation defects on xenon images were matched to morphological findings on standard CT images and incremental diagnostic information of xenon ventilation images was recorded if present. Mean xenon consumption was 2.95 l per patient. No adverse events occurred under xenon inhalation. In the visual CT analysis, the Xe-DECT ventilation defects matched with pathologic changes in lung parenchyma seen in the standard CT images in all patients. Xe-DECT provided additional diagnostic findings in 4/13 patients. These included preserved ventilation despite early pneumonia (n=1), more confident discrimination between a large bulla and pneumothorax (n=1), detection of an airway-to-pneumothorax fistula (n=1) and exclusion of a suspected airway-to-mediastinum fistula (n=1). In all 4 patients, the additional findings had a substantial impact on patients' management. Xenon-enhanced DECT is safely feasible and can add relevant diagnostic information in mechanically ventilated intensive care patients with worsening respiratory function. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  17. Age-Related Differences in Reorganization of Functional Connectivity for a Dual Task with Increasing Postural Destabilization

    PubMed Central

    Huang, Cheng-Ya; Lin, Linda L.; Hwang, Ing-Shiou

    2017-01-01

    The aged brain may not make good use of central resources, so dual task performance may be degraded. From the brain connectome perspective, this study investigated dual task deficits of older adults that lead to task failure of a suprapostural motor task with increasing postural destabilization. Twelve younger (mean age: 25.3 years) and 12 older (mean age: 65.8 years) adults executed a designated force-matching task from a level-surface or a stabilometer board. Force-matching error, stance sway, and event-related potential (ERP) in the preparatory period were measured. The force-matching accuracy and the size of postural sway of the older adults tended to be more vulnerable to stance configuration than that of the young adults, although both groups consistently showed greater attentional investment on the postural task as sway regularity increased in the stabilometer condition. In terms of the synchronization likelihood (SL) of the ERP, both younger and older adults had net increases in the strengths of the functional connectivity in the whole brain and in the fronto-sensorimotor network in the stabilometer condition. Also, the SL in the fronto-sensorimotor network of the older adults was greater than that of the young adults for both stance conditions. However, unlike the young adults, the older adults did not exhibit concurrent deactivation of the functional connectivity of the left temporal-parietal-occipital network for postural-suprapostural task with increasing postural load. In addition, the older adults potentiated functional connectivity of the right prefrontal area to cope with concurrent force-matching with increasing postural load. In conclusion, despite a universal negative effect on brain volume conduction, our preliminary results showed that the older adults were still capable of increasing allocation of neural sources, particularly via compensatory recruitment of the right prefrontal loop, for concurrent force-matching under the challenging postural

  18. Linear dispersion properties of ring velocity distribution functions

    SciTech Connect

    Vandas, Marek, E-mail: marek.vandas@asu.cas.cz; Hellinger, Petr; Institute of Atmospheric Physics, AS CR, Bocni II/1401, CZ-14100 Prague

    2015-06-15

    Linear properties of ring velocity distribution functions are investigated. The dispersion tensor in a form similar to the case of a Maxwellian distribution function, but for a general distribution function separable in velocities, is presented. Analytical forms of the dispersion tensor are derived for two cases of ring velocity distribution functions: one obtained from physical arguments and one for the usual, ad hoc ring distribution. The analytical expressions involve generalized hypergeometric, Kampé de Fériet functions of two arguments. For a set of plasma parameters, the two ring distribution functions are compared. At the parallel propagation with respect to the ambientmore » magnetic field, the two ring distributions give the same results identical to the corresponding bi-Maxwellian distribution. At oblique propagation, the two ring distributions give similar results only for strong instabilities, whereas for weak growth rates their predictions are significantly different; the two ring distributions have different marginal stability conditions.« less

  19. Improving the tribological and corrosive properties of MoS2-based coatings by dual-doping and multilayer construction

    NASA Astrophysics Data System (ADS)

    Shang, Kedong; Zheng, Shaoxian; Ren, Siming; Pu, Jibin; He, Dongqing; Liu, Shuan

    2018-04-01

    The pure MoS2 coating always performs high friction coefficient and short service life when used in high humidity or after long-time storage in humid atmospheric environment. In this study, the MoS2/Pb-Ti composite and MoS2/Pb-Ti multilayer coatings are deposited to improve the corrosion resistance in 3.5 wt% NaCl solution and tribological performance in high humidity condition. The electrochemical impedance spectra and salt spray test shown that the MoS2/Pb-Ti composite and multilayer coatings can inhibit the permeation of oxygen and other corrosive elements, thus resulting a high corrosion resistance. Furthermore, compared with pure MoS2 coating, the tribological performance of the MoS2/Pb-Ti composite and multilayer coatings is also improved significantly owing to the high mechanical properties and compact structure. Moreover, the heterogenous interfaces in MoS2/Pb-Ti multilayer coating play an important role to improve the corrosion resistance and tribological performance of coatings. Overall, the dual-doping and multilayer construction are promising approaches to design the MoS2 coatings as the environmentally adaptive lubricants.

  20. SiCO-doped carbon fibers with unique dual superhydrophilicity/superoleophilicity and ductile and capacitance properties.

    PubMed

    Lu, Ping; Huang, Qing; Mukherjee, Amiya; Hsieh, You-Lo

    2010-12-01

    Silicon oxycarbide (SiCO) glass-doped carbon fibers with an average diameter of 163 nm were successfully synthesized by electrospinning polymer mixtures of preceramic precursor polyureasilazane (PUS) and carbon precursor polyacrylonitrile (PAN) into fibers then converting to ceramic/carbon hybrid via cross-linking, stabilization, and pyrolysis at temperatures up to 1000 °C. The transformation of PUS/PAN polymer precursors to SiCO/carbon structures was confirmed by EDS and FTIR. Both carbon and SiCO/carbon fibers were amorphous and slightly oxidized. Doping with SiCO enhanced the thermal stability of carbon fibers and acquired new ductile behavior in the SiCO/carbon fibers with significantly improved flexibility and breaking elongation. Furthermore, the SiCO/carbon fibers exhibited dual superhydrophilicity and superoleophilicity with water and decane absorbing capacities of 873 and 608%, respectively. The cyclic voltammetry also showed that SiCO/carbon composite fibers possess better capacitor properties than carbon fibers.

  1. Electroluminescence Properties of IrQ(ppy)2 Dual-Emitter Organometallic Compound in Organic Light-Emitting Devices

    NASA Astrophysics Data System (ADS)

    Ciobotaru, Constantin Claudiu; Polosan, Silviu; Ciobotaru, Iulia Corina

    2018-02-01

    This paper reports the influence of the charge carrier mobility on the electroluminescent properties of a dual-emitter organometallic compound dispersed in two conjugated organic small-molecule host materials and embedded in organic light-emitting devices (OLEDs). The electroluminescent processes in OLEDs are strongly influenced by the host-guest interaction. The charge carrier mobility in the host material plays an important role in the electroluminescent processes but also depends on the triplet-triplet interaction with the organometallic compound. The low charge carrier mobility in 4,4'-bis( N-carbazolyl)-1,1'-biphenyl (CBP) host material reduces the electroluminescent processes, but they are slightly enhanced by the triplet-triplet exothermic charge transfer. The higher charge carrier mobility in the case of N, N'-bis(3-methylphenyl)- N, N'-diphenylbenzidine (TPD) host material influences the electroluminescent processes by the endothermic energy transfer at room temperature, which facilitates the triplet-triplet harvesting in the host-guest system. The excitation is transferred to the guest molecules by triplet-triplet interaction as a Dexter transfer, which occurs by endothermic transfer from the triplet exciton in the host to the triplet exciton in the guest.

  2. Influence of fracture network physical properties on stability criteria of density-driven flow in a dual-porosity system

    NASA Astrophysics Data System (ADS)

    Hassanzadeh, H.; Jafari Raad, S. M.

    2017-12-01

    Linear stability analysis is conducted to study the onset of buoyancy-driven convection involved in solubility trapping of CO2 into deep fractured aquifers. In this study, the effect of fracture network physical properties on the stability criteria in a brine-rich fractured porous layer is investigated using dual porosity concept for both single and variable matrix block size distributions. Linear stability analysis results show that both fracture interporosity flow and fracture storativity factors play an important role in the stability behavior of the system. It is shown that a diffusive boundary layer under the gravity field in a fractured rock with lower fracture storativity and/or higher fracture interporosity flow coefficient is more stable. We present scaling relations that relate the onset of convective instability in fractured aquifers. These findings improve our understanding of buoyancy driven flow in fractured aquifers and are particularly important in estimation of potential storage capacity, risk assessment, and storage sites characterization and screening.Keywords: CO2 sequestration; fractured rock; buoyancy-driven convection; stability analysis

  3. Classification of Dual-Wavelength Airborne Laser Scanning Point Cloud Based on the Radiometric Properties of the Objects

    NASA Astrophysics Data System (ADS)

    Pilarska, M.

    2018-05-01

    Airborne laser scanning (ALS) is a well-known and willingly used technology. One of the advantages of this technology is primarily its fast and accurate data registration. In recent years ALS is continuously developed. One of the latest achievements is multispectral ALS, which consists in obtaining simultaneously the data in more than one laser wavelength. In this article the results of the dual-wavelength ALS data classification are presented. The data were acquired with RIEGL VQ-1560i sensor, which is equipped with two laser scanners operating in different wavelengths: 532 nm and 1064 nm. Two classification approaches are presented in the article: classification, which is based on geometric relationships between points and classification, which mostly relies on the radiometric properties of registered objects. The overall accuracy of the geometric classification was 86 %, whereas for the radiometric classification it was 81 %. As a result, it can be assumed that the radiometric features which are provided by the multispectral ALS have potential to be successfully used in ALS point cloud classification.

  4. Functional test of pedotransfer functions to predict water flow and solute transport with the dual-permeability model MACRO

    NASA Astrophysics Data System (ADS)

    Moeys, J.; Larsbo, M.; Bergström, L.; Brown, C. D.; Coquet, Y.; Jarvis, N. J.

    2012-07-01

    Estimating pesticide leaching risks at the regional scale requires the ability to completely parameterise a pesticide fate model using only survey data, such as soil and land-use maps. Such parameterisations usually rely on a set of lookup tables and (pedo)transfer functions, relating elementary soil and site properties to model parameters. The aim of this paper is to describe and test a complete set of parameter estimation algorithms developed for the pesticide fate model MACRO, which accounts for preferential flow in soil macropores. We used tracer monitoring data from 16 lysimeter studies, carried out in three European countries, to evaluate the ability of MACRO and this "blind parameterisation" scheme to reproduce measured solute leaching at the base of each lysimeter. We focused on the prediction of early tracer breakthrough due to preferential flow, because this is critical for pesticide leaching. We then calibrated a selected number of parameters in order to assess to what extent the prediction of water and solute leaching could be improved. Our results show that water flow was generally reasonably well predicted (median model efficiency, ME, of 0.42). Although the general pattern of solute leaching was reproduced well by the model, the overall model efficiency was low (median ME = -0.26) due to errors in the timing and magnitude of some peaks. Preferential solute leaching at early pore volumes was also systematically underestimated. Nonetheless, the ranking of soils according to solute loads at early pore volumes was reasonably well estimated (concordance correlation coefficient, CCC, between 0.54 and 0.72). Moreover, we also found that ignoring macropore flow leads to a significant deterioration in the ability of the model to reproduce the observed leaching pattern, and especially the early breakthrough in some soils. Finally, the calibration procedure showed that improving the estimation of solute transport parameters is probably more important than the

  5. Rheological and Functional Properties of Catfish Skin Protein Hydrolysates

    USDA-ARS?s Scientific Manuscript database

    Catfish skin is an abundant and underutilized resource that can be used as a unique protein source to make fish skin hydrolysates. The objectives of this study were to: isolating soluble and insoluble proteins from hydrolyzed catfish skin and study the chemical and functional properties of the prote...

  6. Psychometric Properties of the Volunteer Functions Inventory with Chinese Students

    ERIC Educational Resources Information Center

    Wu, Joseph; Lo, T. Wing; Liu, Elaine S. C.

    2009-01-01

    The authors report an evaluation of the psychometric properties of a Chinese version of the Volunteer Functions Inventory on a sample of university student volunteers. Reliabilities were high for four out of the six scales of the Inventory (Values, Career, Social, and Understanding) in terms of internal consistency. Items in these four scales also…

  7. Effect of hydrocolloids on functional properties of navy bean starch

    USDA-ARS?s Scientific Manuscript database

    Pulses are recognized as a low-fat source of gluten-free protein, soluble fiber, B-vitamins and minerals, and their use in foods has increased in recent years. The functional properties of pulse starches have received relatively little attention, but they are important since starch is the major comp...

  8. Properties of Zero-Free Transfer Function Matrices

    NASA Astrophysics Data System (ADS)

    D. O. Anderson, Brian; Deistler, Manfred

    Transfer functions of linear, time-invariant finite-dimensional systems with more outputs than inputs, as arise in factor analysis (for example in econometrics), have, for state-variable descriptions with generic entries in the relevant matrices, no finite zeros. This paper gives a number of characterizations of such systems (and indeed square discrete-time systems with no zeros), using state-variable, impulse response, and matrix-fraction descriptions. Key properties include the ability to recover the input values at any time from a bounded interval of output values, without any knowledge of an initial state, and an ability to verify the no-zero property in terms of a property of the impulse response coefficient matrices. Results are particularized to cases where the transfer function matrix in question may or may not have a zero at infinity or a zero at zero.

  9. Can dual-energy CT replace perfusion CT for the functional evaluation of advanced hepatocellular carcinoma?

    PubMed

    Mulé, Sébastien; Pigneur, Frédéric; Quelever, Ronan; Tenenhaus, Arthur; Baranes, Laurence; Richard, Philippe; Tacher, Vania; Herin, Edouard; Pasquier, Hugo; Ronot, Maxime; Rahmouni, Alain; Vilgrain, Valérie; Luciani, Alain

    2018-05-01

    To determine the degree of relationship between iodine concentrations derived from dual-energy CT (DECT) and perfusion CT parameters in patients with advanced HCC under treatment. In this single-centre IRB approved study, 16 patients with advanced HCC treated with sorafenib or radioembolization who underwent concurrent dynamic perfusion CT and multiphase DECT using a single source, fast kV switching DECT scanner were included. Written informed consent was obtained for all patients. HCC late-arterial and portal iodine concentrations, blood flow (BF)-related and blood volume (BV)-related perfusion parameters maps were calculated. Mixed-effects models of the relationship between iodine concentrations and perfusion parameters were computed. An adjusted p value (Bonferroni method) < 0.05 was considered significant. Mean HCC late-arterial and portal iodine concentrations were 22.7±12.7 mg/mL and 18.7±8.3 mg/mL, respectively. Late-arterial iodine concentration was significantly related to BV (mixed-effects model F statistic (F)=28.52, p<0.0001), arterial BF (aBF, F=17.62, p<0.0001), hepatic perfusion index (F=28.24, p<0.0001), positive enhancement integral (PEI, F=66.75, p<0.0001) and mean slope of increase (F=32.96, p<0.0001), while portal-venous iodine concentration was mainly related to BV (F=29.68, p<0.0001) and PEI (F=66.75, p<0.0001). In advanced HCC lesions, DECT-derived late-arterial iodine concentration is strongly related to both aBF and BV, while portal iodine concentration mainly reflects BV, offering DECT the ability to evaluate both morphological and perfusion changes. • Late-arterial iodine concentration is highly related to arterial BF and BV. • Portal iodine concentration mainly reflects tumour blood volume. • Dual-energy CT offers significantly decreased radiation dose compared with perfusion CT.

  10. LSD1 dual function in mediating epigenetic corruption of the vitamin D signaling in prostate cancer.

    PubMed

    Battaglia, Sebastiano; Karasik, Ellen; Gillard, Bryan; Williams, Jennifer; Winchester, Trisha; Moser, Michael T; Smiraglia, Dominic J; Foster, Barbara A

    2017-01-01

    Lysine-specific demethylase 1A (LSD1) is a key regulator of the androgen (AR) and estrogen receptors (ER), and LSD1 levels correlate with tumor aggressiveness. Here, we demonstrate that LSD1 regulates vitamin D receptor (VDR) activity and is a mediator of 1,25(OH) 2 -D 3 (vitamin D) action in prostate cancer (PCa). Athymic nude mice were xenografted with CWR22 cells and monitored weekly after testosterone pellet removal. Expression of LSD1 and VDR (IHC) were correlated with tumor growth using log-rank test. TRAMP tumors and prostates from wild-type (WT) mice were used to evaluate VDR and LSD1 expression via IHC and western blotting. The presence of VDR and LSD1 in the same transcriptional complex was evaluated via immunoprecipitation (IP) using nuclear cell lysate. The effect of LSD1 and 1,25(OH) 2 -D 3 on cell viability was evaluated in C4-2 and BC1A cells via trypan blue exclusion. The role of LSD1 in VDR-mediated gene transcription was evaluated for Cdkn1a , E2f1 , Cyp24a1 , and S100g via qRT-PCR-TaqMan and via chromatin immunoprecipitation assay. Methylation of Cdkn1a TSS was measured via bisulfite sequencing, and methylation of a panel of cancer-related genes was quantified using methyl arrays. The Cancer Genome Atlas data were retrieved to identify genes whose status correlates with LSD1 and DNA methyltransferase 1 (DNMT1). Results were correlated with patients' survival data from two separate cohorts of primary and metastatic PCa. LSD1 and VDR protein levels are elevated in PCa tumors and correlate with faster tumor growth in xenograft mouse models. Knockdown of LSD1 reduces PCa cell viability, and gene expression data suggest a dual coregulatory role of LSD1 for VDR, acting as a coactivator and corepressor in a locus-specific manner. LSD1 modulates VDR-dependent transcription by mediating the recruitment of VDR and DNMT1 at the TSS of VDR-targeted genes and modulates the epigenetic status of transcribed genes by altering H3K4me2 and H3K9Ac and DNA

  11. Covalent Organic Framework Functionalized with 8-Hydroxyquinoline as a Dual-Mode Fluorescent and Colorimetric pH Sensor.

    PubMed

    Chen, Long; He, Linwei; Ma, Fuyin; Liu, Wei; Wang, Yaxing; Silver, Mark A; Chen, Lanhua; Zhu, Lin; Gui, Daxiang; Diwu, Juan; Chai, Zhifang; Wang, Shuao

    2018-05-09

    Real-time and accurate detection of pH in aqueous solution is of great significance in chemical, environmental, and engineering-related fields. We report here the use of 8-hydroxyquinoline-functionalized covalent organic framework (COF-HQ) for dual-mode pH sensing. In the fluorescent mode, the emission intensity of COF-HQ weakened as the pH decreased, and also displayed a good linear relationship against pH in the range from 1 to 5. In addition, COF-HQ showed discernible color changes from yellow to black as the acidity increased and can be therefore used as a colorimetric pH sensor. All these changes are reversible and COF-HQ can be recycled for multiple detection runs owing to its high hydrolytical stability. It can be further assembled into a mixed matrix membrane for practical applications.

  12. Dual-Function Metal-Organic Framework as a Versatile Catalyst for Detoxifying Chemical Warfare Agent Simulants.

    PubMed

    Liu, Yangyang; Moon, Su-Young; Hupp, Joseph T; Farha, Omar K

    2015-12-22

    The nanocrystals of a porphyrin-based zirconium(IV) metal-organic framework (MOF) are used as a dual-function catalyst for the simultaneous detoxification of two chemical warfare agent simulants at room temperature. Simulants of nerve agent (such as GD, VX) and mustard gas, dimethyl 4-nitrophenyl phosphate and 2-chloroethyl ethyl sulfide, have been hydrolyzed and oxidized, respectively, to nontoxic products via a pair of pathways catalyzed by the same MOF. Phosphotriesterase-like activity of the Zr6-containing node combined with photoactivity of the porphyrin linker gives rise to a versatile MOF catalyst. In addition, bringing the MOF crystals down to the nanoregime leads to acceleration of the catalysis.

  13. Dual-responsive and Multi-functional Plasmonic Hydrogel Valves and Biomimetic Architectures Formed with Hydrogel and Gold Nanocolloids

    PubMed Central

    Song, Ji Eun; Cho, Eun Chul

    2016-01-01

    We present a straightforward approach with high moldability for producing dual-responsive and multi-functional plasmonic hydrogel valves and biomimetic architectures that reversibly change volumes and colors in response to temperature and ion variations. Heating of a mixture of hybrid colloids (gold nanoparticles assembled on a hydrogel colloid) and hydrogel colloids rapidly induces (within 30 min) the formation of hydrogel architectures resembling mold shapes (cylinder, fish, butterfly). The biomimetic fish and butterfly display reversible changes in volumes and colors with variations of temperature and ionic conditions in aqueous solutions. The cylindrical plasmonic valves installed in flow tubes rapidly control water flow rate in on-off manner by responding to these stimuli. They also report these changes in terms of their colors. Therefore, the approach presented here might be helpful in developing new class of biomimetic and flow control systems where liquid conditions should be visually notified (e.g., glucose or ion concentration changes). PMID:27703195

  14. Physical properties of biophotons and their biological functions.

    PubMed

    Chang, Jiin-Ju

    2008-05-01

    Biophotons (BPHs) are weak photons within or emitted from living organisms. The intensities of BPHs range from a few to several hundred photons s(-1) x cm(-2). BPH emission originates from a de-localized coherent electromagnetic field within the living organisms and is regulated by the field. In this paper based on the experimental results of Poisson and sub-Poisson distributions of photocount statistics, the coherent properties of BPHs and their functions in cell communication are described. Discussions are made on functions which BPHs may play in DNA and proteins functioning including the process of DNA replication, protein synthesis and cell signalling and in oxidative phosporylation and photosynthesis.

  15. Fabrication of quantum dot/silica core-shell particles immobilizing Au nanoparticles and their dual imaging functions

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yoshio; Matsudo, Hiromu; Li, Ting-ting; Shibuya, Kyosuke; Kubota, Yohsuke; Oikawa, Takahiro; Nakagawa, Tomohiko; Gonda, Kohsuke

    2016-03-01

    The present work proposes preparation methods for quantum dot/silica (QD/SiO2) core-shell particles that immobilize Au nanoparticles (QD/SiO2/Au). A colloid solution of QD/SiO2 core-shell particles with an average size of 47.0 ± 6.1 nm was prepared by a sol-gel reaction of tetraethyl orthosilicate in the presence of the QDs with an average size of 10.3 ± 2.1 nm. A colloid solution of Au nanoparticles with an average size of 17.9 ± 1.3 nm was prepared by reducing Au3+ ions with sodium citrate in water at 80 °C. Introduction of amino groups to QD/SiO2 particle surfaces was performed using (3-aminopropyl)-triethoxysilane (QD/SiO2-NH2). The QD/SiO2/Au particles were fabricated by mixing the Au particle colloid solution and the QD/SiO2-NH2 particle colloid solution. Values of radiant efficiency and computed tomography for the QD/SiO2/Au particle colloid solution were 2.23 × 107 (p/s/cm2/sr)/(μW/cm2) at a QD concentration of 8 × 10-7 M and 1180 ± 314 Hounsfield units and an Au concentration of 5.4 × 10-2 M. The QD/SiO2/Au particle colloid solution was injected into a mouse chest wall. Fluorescence emitted from the colloid solution could be detected on the skin covering the chest wall. The colloid solution could also be X-ray-imaged in the chest wall. Consequently, the QD/SiO2/Au particle colloid solution was found to have dual functions, i.e., fluorescence emission and X-ray absorption in vivo, which makes the colloid solution suitable to function as a contrast agent for dual imaging processes.

  16. Polydopamine-based functional composite particles for tumor cell targeting and dual-mode cellular imaging.

    PubMed

    Zhou, Yalei; Zhou, Jie; Wang, Feng; Yang, Haifeng

    2018-05-01

    Particles which bear tumor cell targeting and multimode imaging capabilities are promising in tumor diagnosis and cancer therapy. A simple and versatile method to fabricate gold/polydopamine-Methylene Blue@Bovine Serum Albumin-glutaraldehyde-Transferrin composite particles (Au/PDA-MB@BSA-GA-Tf NPs) for tumor cell targeting and fluorescence (FL) / surface-enhanced Raman scattering (SERS) dual-modal imaging were reported in this work. Polydopamine (PDA) spheres played an important role in gold ion reduction, gold nanoparticle (Au NPs) binding and methylene blue (MB) adsorption, MB were employed as both fluorescence label and Raman reporter. In addition, glutaraldehyde (GA) crosslinked bovine serum albumin (BSA) in the outer layer of Au/PDA-MB nanoparticles can prevent MB from dissociation and leakage. The composite nanoparticles were further conjugated with transferrin (Tf) to target transferrin receptor (TfR)-overexpressed cancer cells. The targeting ability as well as the intracellular location of the probe was investigated through SERS mapping and fluorescence imaging. Their excellent biocompatibility was demonstrated by low cytotoxicity against breast cancer cell (4T1 cell). Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Dual role of Ski in pancreatic cancer cells: tumor-promoting versus metastasis-suppressive function.

    PubMed

    Wang, Peng; Chen, Zhen; Meng, Zhi-Qiang; Fan, Jie; Luo, Jian-Min; Liang, Wang; Lin, Jun-Hua; Zhou, Zhen-Hua; Chen, Hao; Wang, Kun; Shen, Ye-Hua; Xu, Zu-De; Liu, Lu-Ming

    2009-09-01

    Ski used to be defined as an oncogene that contributes to the resistance of tumor cells to transforming growth factor-beta (TGF-beta)-induced growth arrest. As TGF-beta has a dual effect on tumor growth with both tumor-suppressing and -promoting activity depending on the stage of carcinogenesis and the cell type, the precise role of Ski in carcinogenesis remains unclear. In this study, we show that downregulation of Ski through lentivirus-mediated RNA interference decreases tumor growth both in vitro and in vivo, yet promotes cell invasiveness in vitro, and lung metastasis in vivo in the pancreatic cancer cell line SW1990, which contain wild-type Smad4 expression, and the BxPC3 cell line, which is Smad4 deficient. We also show that the downregulation of Ski increases TGF-beta-induced transcriptional activity, which is associated with increased TGF-beta-dependent Smad2/3 phosphorylation, and results in an altered expression profile of TGF-beta-inducible genes involved in metastasis, angiogenesis and cell proliferation and epithelial-mesenchymal transition. Immunohistochemical analysis of specimens from 71 patients with pancreatic adenocarcinoma showed a significant association between overexpression of Ski and decreased patient survival time (P = 0.0024). Our results suggest that Ski may act as a tumor proliferation-promoting factor or as a metastatic suppressor in human pancreatic cancer.

  18. Functional properties of yam bean (Pachyrhizus erosus) starch.

    PubMed

    Mélo, E A; Stamford, T L M; Silva, M P C; Krieger, N; Stamford, N P

    2003-08-01

    The study was carried out in order to determine and establish the functional characters of starch extracted from yam bean (Pachyrhizus erosus (L) Urban) compared with cassava starch. Yam bean is a tropical tuber legume easily grown and holds a great potential as a new source of starch. Yam bean starch shows functional properties which are peculiar to those of most starch root crops. Gelatinization temperature (53-63 degrees C) and the pasting temperature (64.5 degrees C) are less than those of cereal starch, however, the swelling power is high (54.4 g gel/g dried starch). Yam bean starch paste presents a high viscosity profile, high retrogradation tendency and low stability on cooking. The functional properties of yam bean starch, similar to those of cassava starch, allows yam bean to be used as a potential new source of starch.

  19. A dual-satellite study of the spatial properties of FTEs. [flux transfer events

    NASA Technical Reports Server (NTRS)

    Saunders, M. A.; Russell, C. T.; Sckopke, N.

    1984-01-01

    Reconnection at the earth's dayside magnetopause may manifest itself primarily as a localized and transient process called a flux-transfer event (FTE). The spatial properties of FTEs are investigated directly by examining data from the ISEE satellite pair when the satellites were separated by more than 1000 km in the vicinity of the magnetopause. Examples of magnetosheath and boundary layer FTEs, each having a dimension normal to the magnetopause of order an earth radius, R(E), are shown, and this scale-size result is substantiated statistically for magnetosheath FTEs. When combined with other information, a 1-R(E) normal dimension implies that the voltage associated with the FTE process at one magnetopause location is at least 10 kV. These findings strengthen the view that the magnetic field comprising an FTE is twisted, this twisting appearing to be continuous in sense across the magnetopause and corresponding to a core field-aligned current of magnitude a few hundred kA. Changes in plasma flow speed and direction are found to be associated with FTEs. The transverse field and flow perturbations accompanying the three magnetosheath FTEs studied here satisfy approximately the Walen relation, the relation which describes a propagating Alfven wave.

  20. Microstructure, Tensile Properties and Work Hardening Behavior of GTA-Welded Dual-Phase Steels

    NASA Astrophysics Data System (ADS)

    Ashrafi, H.; Shamanian, M.; Emadi, R.; Saeidi, N.

    2017-03-01

    In the present study, microstructure, tensile properties and work hardening behavior of a DP700 steel after gas tungsten arc welding were investigated. Formation of bainite in the fusion zone resulted in a hardness increase compared to that for the base metal (BM), whereas tempering of the pre-existing martensite in the subcritical heat-affected zone (HAZ) led to softening. The GTA-welded joint exhibited a continuous yielding behavior and a yield strength close to that for the BM, while its ultimate tensile strength and total elongation were lower than those for the BM owing to the formation of soft zone in the HAZ. A joint efficiency of about 81% was obtained for the GTA-welded joint, and it failed in the softened HAZ. Analysis of work hardening based on the Kocks-Mecking approach showed one stage of hardening behavior corresponding to the stage III for both the DP700 BM and welded sample. It was also revealed that the DP700 BM has larger values of work hardening exponent and magnitude of work hardening compared with the welded sample. Analysis of fractured surfaces showed that the dominant fracture mode for both the DP700 BM and welded joint was ductile.

  1. A single microfluidic chip with dual surface properties for protein drug delivery.

    PubMed

    Bokharaei, Mehrdad; Saatchi, Katayoun; Häfeli, Urs O

    2017-04-15

    Principles of double emulsion generation were incorporated in a glass microfluidic chip fabricated with two different surface properties in order to produce protein loaded polymer microspheres. The microspheres were produced by integrating two microfluidic flow focusing systems and a multi-step droplet splitting and mixing system into one chip. The chip consists of a hydrophobic and a hydrophilic section with two different heights, 12μm and 45μm, respectively. As a result, the protein is homogenously distributed throughout the polymer microsphere matrix, not just in its center (which has been studied before). In our work, the inner phase was bovine serum albumin (BSA) in phosphate buffered saline, the disperse phase was poly (lactic acid) in chloroform and the continuous phase was an aqueous solution of poly(vinyl alcohol). After solvent removal, BSA loaded microspheres with an encapsulation efficiency of up to 96% were obtained. Our results show the feasibility of producing microspheres loaded with a hydrophilic drug in a microfluidic system that integrates different microfluidic units into one chip. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Hydroxylated chalcones with dual properties: xanthine oxidase inhibitors and radical scavengers

    PubMed Central

    Hofmann, Emily; Webster, Jonathan; Do, Thuy; Kline, Reid; Snider, Lindsey; Hauser, Quintin; Higginbottom, Grace; Campbell, Austin; Ma, Lili; Paula, Stefan

    2016-01-01

    In this study, we evaluated the abilities of a series of chalcones to inhibit the activity of the enzyme xanthine oxidase (XO) and to scavenge radicals. 20 mono- and polyhydroxylated chalcone derivatives were synthesized by Claisen-Schmidt condensation reactions and then tested for inhibitory potency against XO, a known generator of reactive oxygen species (ROS). In parallel, the ability of the synthesized chalcones to scavenge a stable radical was determined. Structure-activity relationship analysis in conjunction with molecular docking indicated that the most active XO inhibitors carried a minimum of three hydroxyl groups. Moreover, the most effective radical scavengers had two neighboring hydroxyl groups on at least one of the two phenyl rings. Since it has been proposed previously that XO inhibition and radical scavenging could be useful properties for reduction of ROS-levels in tissue, we determined the chalcones’ effects to rescue neurons subjected to ROS-induced stress created by the addition of β-amyloid peptide. Best protection was provided by chalcones that combined good inhibitory potency with high radical scavenging ability in a single molecule, an observation that points to a potential therapeutic value of this compound class. PMID:26762836

  3. The Dual Role of Vegetation as a Constraint on Mass and Energy Flux into the Critical Zone and as an Emergent Property of Geophysical Critical Zone Structure

    NASA Astrophysics Data System (ADS)

    Brooks, P. D.; Swetnam, T. L.; Barnard, H. R.; Singha, K.; Harpold, A.; Litvak, M. E.

    2017-12-01

    Spatial patterns in vegetation long have been used to scale both landsurface-atmosphere exchanges of water and carbon as well as to infer subsurface structure. These pursuits typical proceed in isolation and rarely do inferences gained from one community propagate to related efforts in another. Perhaps more importantly, vegetation often is treated as an emergent property of landscape-climate interactions rather than an active modifier of both critical zone structure and energy fluxes. We posit that vegetation structure and activity are under utilized as a tool towards understanding landscape evolution and present examples that begin to disentangle the role of vegetation as both an emergent property and an active control on critical zone structure and function. As climate change, population growth, and land use changes threaten water resources worldwide, the need for the new insights vegetation can provide becomes not just a basic science priority, but a pressing applied science question with clear societal importance. This presentation will provide an overview of recent efforts to address the dual role of vegetation in both modifying and reflecting critical zone structure in the western North American forests. For example, interactions between topography and stand scale vegetation structure influence both solar radiation and turbulence altering landscape scale partitioning of evaporation vs transpiration with major impacts of surface water supply. Similarly, interactions between topographic shading, lateral redistribution of plant available water, and subsurface storage create a mosaic of drought resistance and resilience across complex terrain. These complex interactions between geophysical and vegetation components of critical zone structure result in predictable patterns in catchment scale hydrologic partitioning within individual watersheds while simultaneously suggesting testable hypotheses for why catchments under similar climate regimes respond so

  4. Construction of dual-functional polymer nanomaterials with near-infrared fluorescence imaging and polymer prodrug by RAFT-mediated aqueous dispersion polymerization.

    PubMed

    Tian, Chun; Niu, Jinyun; Wei, Xuerui; Xu, Yujie; Zhang, Lifen; Cheng, Zhenping; Zhu, Xiulin

    2018-05-31

    The performance of functional polymer nanomaterials is a vigorously discussed topic in polymer science. We devoted ourselves to investigating polymer nanomaterials based on near-infrared (NIR) fluorescence imaging and polymer prodrug in this study. Aza-boron dipyrromethene (BODIPY) is an important organic dye, having characteristics such as environmental resistance, light resistance, high molar extinction coefficient, and fluorescence quantum yield. We incorporated it into our target monomer, which can be polymerized without changing its parent structure in a polar solvent and copolymerized with water-soluble monomer to improve the solubility of the dye in an aqueous solution. At the same time, the hydrophobic drug camptothecin (CPT) was designed as a prodrug monomer, and the polymeric nanoparticles (NPs) with NIR fluorescence imaging and prodrug were synthesized in situ in reversible addition-fragmentation chain transfer (RAFT)-mediated aqueous dispersion polymerization. The dynamic light scattering (DLS) and transmission electron microscopy (TEM) revealed the final uniform size of the dual-functional polymeric NPs morphology. The dual-functional polymeric NPs had a strong absorption and emission signal in the NIR region (>650 nm) based on the fluorescence tests. In consideration of the long-term biological toxicity, confocal laser scanning microscopy (CLSM) results indicated that the dual-functional NPs with controlled drug content exhibited effective capability of killing HeLa cells. In addition, in vivo imaging of the dual-functional NPs was observed in real time, and the fluorescent signals clearly demonstrated the dynamic process of prodrug transfer.

  5. Composition-microstructure-property relationships in dual phase bulk magnetoelectric composite

    NASA Astrophysics Data System (ADS)

    Islam, Rashed Adnan

    The coexistence of coupled electrical and magnetic properties in the "magnetoelectric" material has led to the possibility of developing smarter and smaller electronic components. In order to make this possibility a reality, significant efforts are required to understand the science of magnetoelectric (ME) behavior and apply this understanding to develop higher sensitivity material. The primary aims of this thesis are to identify the role of composition, microstructural variables, composite geometry, texturing, post sintering heat treatment, and nanoscale assembly on ME coefficient. The overall objective is to synthesize, characterize and utilize a high ME coefficient composite. The desired range of ME coefficient in the sintered composite is more than 1.5 V/cm.Oe. At first, a piezoelectric composition in the system of Pb(Zr,Ti)O 3 - Pb[(Zn,Ni)1/3Nb2/3]O3 was designed and synthesized which has high energy density (d.g) parameter of 18456.2 x 10-15m2/N and high g constant of 83.1 V-m/N in order to use it as the matrix in piezoelectric---magnetostrictive composite. Secondly it was found that soft piezoelectric phase shows much better magnetoelectric response. The magnetoelectric coefficient for Pb(Zr 0.52Ti0.48)O3 - 15% Pb(Zn1/3Nb 2/3)O3 [PZT - 15 PZN] - 20% Ni0.8Zn 0.2Fe2O4 was found to be around 186 mV/cm.Oe. Thridly, soft magnetic phase with lower coercivity and higher magnetization was found to be suitable for high ME coefficient. Zinc doped Ni-ferrite has higher resistivity, permeability, magnetization and it was found that with increasing Zn concentration the ME coefficient increases exhibiting maxima near 30 at% Zn (138 mV/cm.Oe). Fourthly, if the connectivity was changed from (0-3) to (2-2) which is a bilayer geometry, improved piezoelectric (d33 ˜ 80 pC/N), ferroelectric (polarization = 60 muC/cm2), magnetization (25 emu/gm) and lower coercive field (2.8 Oe) were measured. The bilayer shows an enhancement of 67% increase in ME coefficient compared to bulk

  6. Non-metal single/dual doped carbon quantum dots: a general flame synthetic method and electro-catalytic properties

    NASA Astrophysics Data System (ADS)

    Han, Yuzhi; Tang, Di; Yang, Yanmei; Li, Chuanxi; Kong, Weiqian; Huang, Hui; Liu, Yang; Kang, Zhenhui

    2015-03-01

    A combustion flame method is developed for the convenient and scalable fabrication of single- and dual-doped carbon quantum dots (CQDs) (N-CQDs, B-CQDs, P-CQDs, and S-CQDs and dual-doped B,N-CQDs, P,N-CQDs, and S,N-CQDs), and the doping contents can be easily adjusted by simply changing the concentrations of precursors in ethanol. These single/dual-doped CQDs, especially B,N-CQDs, show high catalytic activities for the oxygen reduction reaction.A combustion flame method is developed for the convenient and scalable fabrication of single- and dual-doped carbon quantum dots (CQDs) (N-CQDs, B-CQDs, P-CQDs, and S-CQDs and dual-doped B,N-CQDs, P,N-CQDs, and S,N-CQDs), and the doping contents can be easily adjusted by simply changing the concentrations of precursors in ethanol. These single/dual-doped CQDs, especially B,N-CQDs, show high catalytic activities for the oxygen reduction reaction. Electronic supplementary information (ESI) available: TEM images, UV-Vis absorption, PL, Raman, FTIR, XPS, CV, and LSV data of single/dual doped CQDs, a table for the calculated mass concentrations of different atoms in various B, N, P or S containing CQDs and a table for summary of the ORR performance of various catalysts in an O2-saturated 0.1 M KOH solution. See DOI: 10.1039/c4nr07116f

  7. The dual function of and counter-measures for rural population migration.

    PubMed

    Gu, S; Jian, X

    1996-01-01

    The authors posit that migration of the Chinese population from poverty stricken and backward rural areas to economically developed and advanced cities and coastal areas can have a positive effect on economic development and social stability. Policies must eliminate the negative disorderly and ineffective aspects and reinforce the positive, well-organized, orderly, and effective aspects. Population mobility enhances the formation of a national, unified labor market and resource distribution that is responsive to supply and demand. Population mobility allows for the transfer of rural surplus labor, relief of employment pressure in rural areas, and reduced population pressure on land availability. Rural surplus labor that moves into rural township enterprises is a major new source of financial capital for the economic development of rural areas. Population mobility aids in the development of an urban economy and increases farmers' income and living standard. Population mobility increases China's shift to a dual economic mode that includes a modern economy. Adverse effects include a decline in the quality of the rural labor force and diminished capital input into agriculture, a strain on urban resources and social services, and disruption of the socioeconomic order. Population mobility enhances social stability by advancing economic development and standards of living. Population mobility allows for the smooth transfer of surplus labor during periods of economic change to a modern economy. A poor economy and deteriorated living conditions lead to violent social disturbances, social conflicts, and resentment among the public. Adverse effects on social stability include increased crime, housing scarcity and temporary shelters, and social conflicts between urban residents and migrants. Government strategies should include the direction of surplus migrants into multiple channels. Six channels are identified. Rural labor should be encouraged to work in enterprises and to

  8. Topological properties and functionalities in oxide thin films and interfaces

    NASA Astrophysics Data System (ADS)

    Uchida, Masaki; Kawasaki, Masashi

    2018-04-01

    As symbolized by the Nobel Prize in Physics 2016, ‘topology’ has been recognized as an essential standpoint to understand and control the physics of condensed matter. This concept may be spreading even into application areas such as novel electronics. In this trend, there has been reported a number of studies for oxide films and heterostructures with topologically non-trivial electronic or magnetic states. In this review, we overview the trends of new topological properties and functionalities in oxide materials by sorting out a number of examples. The technological advances in oxide film growth achieved over the last few decades are now opening the door for harnessing novel topological properties.

  9. Structural properties of prokaryotic promoter regions correlate with functional features.

    PubMed

    Meysman, Pieter; Collado-Vides, Julio; Morett, Enrique; Viola, Roberto; Engelen, Kristof; Laukens, Kris

    2014-01-01

    The structural properties of the DNA molecule are known to play a critical role in transcription. In this paper, the structural profiles of promoter regions were studied within the context of their diversity and their function for eleven prokaryotic species; Escherichia coli, Klebsiella pneumoniae, Salmonella Typhimurium, Pseudomonas auroginosa, Geobacter sulfurreducens Helicobacter pylori, Chlamydophila pneumoniae, Synechocystis sp., Synechoccocus elongates, Bacillus anthracis, and the archaea Sulfolobus solfataricus. The main anchor point for these promoter regions were transcription start sites identified through high-throughput experiments or collected within large curated databases. Prokaryotic promoter regions were found to be less stable and less flexible than the genomic mean across all studied species. However, direct comparison between species revealed differences in their structural profiles that can not solely be explained by the difference in genomic GC content. In addition, comparison with functional data revealed that there are patterns in the promoter structural profiles that can be linked to specific functional loci, such as sigma factor regulation or transcription factor binding. Interestingly, a novel structural element clearly visible near the transcription start site was found in genes associated with essential cellular functions and growth in several species. Our analyses reveals the great diversity in promoter structural profiles both between and within prokaryotic species. We observed relationships between structural diversity and functional features that are interesting prospects for further research to yet uncharacterized functional loci defined by DNA structural properties.

  10. Electronic properties of functionalized (5,5) beryllium oxide nanotubes.

    PubMed

    Chigo Anota, Ernesto; Cocoletzi, Gregorio Hernández

    2013-05-01

    Using the density functional theory (DFT) we study the structural and electronic properties of functionalized (5,5) chirality single wall beryllium oxide nanotubes (SW-BeONTs), i.e. armchair nanotubes. The nanotube surface and ends are functionalized by the hydroxyl (OH) functional group. Our calculations consider the Hamprecht-Cohen-Tozer-Handy functional in the generalized gradient approximation (HCTH-GGA) to deal with the exchange-correlation energies, and the base function with double polarization (DNP). The geometry optimization of both defects free and with point defects nanotubes is done applying the criterion of minimum energy. Six configurations are considered: The OH oriented toward the Be (on the surface and at the end), toward the O (on the surface and at the end) and placed at the nanotube ends. Simulation results show that the nanotube functionalization takes place at the nanotube ends with the BeO bond displaying hydrogen-like bridge bonds. Moreover the nanotube semiconductor behavior remains unchanged. The polarity is high (it shows a transition from covalent to ionic) favoring solvatation. On the other hand, the work function low value suggests this to be a good candidate for the device fabrication. When the nanotube contains surface point defects the work function is reduced which provides excellent possibilities for the use of this material in the electronic industry. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Assessing language and visuospatial functions with one task: a "dual use" approach to performing fMRI in children.

    PubMed

    Ebner, Kathina; Lidzba, Karen; Hauser, Till-Karsten; Wilke, Marko

    2011-10-01

    In order to increase the rate of successful functional MR studies in children it is helpful to shorten the time spent in the scanner. To this effect, assessing two cognitive functions with one task seems to be a promising approach. The hypothesis of this study was that the control condition of an established language task (vowel identification task, VIT) requires visuospatial processing and that the control condition (VIT(CC)) therefore may also be applicable to localize visuospatial functions. As a reference task, a visual search task (VST, previously established for use in children) was employed. To test this hypothesis, 43 children (19 f, 24 m; 12.0±2.6, range 7.9 to 17.8 years) were recruited and scanned using both tasks. Second-level random effects group analyses showed activation of left inferior-frontal cortex in the active condition of the VIT, as in previous studies. Additionally, analysis of the VIT(CC) demonstrated activation in right-dominant superior parietal and high-frontal brain regions, classically associated with visuospatial functions; activation seen in the VST was similar with a substantial overlap. However, lateralization in the parietal lobe was significantly more bilateral in the VST than in the VIT(CC). This suggests that the VIT can not only be applied to assess language functions (using the active>control contrast), but also that the control>active condition is useful for assessing visuospatial functions. Future task design may benefit from such a "dual use" approach to performing fMRI not only, but also particularly in children. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Dual-wavelength hybrid optoacoustic-ultrasound biomicroscopy for functional imaging of large-scale cerebral vascular networks.

    PubMed

    Rebling, Johannes; Estrada, Héctor; Gottschalk, Sven; Sela, Gali; Zwack, Michael; Wissmeyer, Georg; Ntziachristos, Vasilis; Razansky, Daniel

    2018-04-19

    A critical link exists between pathological changes of cerebral vasculature and diseases affecting brain function. Microscopic techniques have played an indispensable role in the study of neurovascular anatomy and functions. Yet, investigations are often hindered by suboptimal trade-offs between the spatiotemporal resolution, field-of-view (FOV) and type of contrast offered by the existing optical microscopy techniques. We present a hybrid dual-wavelength optoacoustic (OA) biomicroscope capable of rapid transcranial visualization of large-scale cerebral vascular networks. The system offers 3-dimensional views of the morphology and oxygenation status of the cerebral vasculature with single capillary resolution and a FOV exceeding 6 × 8 mm 2 , thus covering the entire cortical vasculature in mice. The large-scale OA imaging capacity is complemented by simultaneously acquired pulse-echo ultrasound (US) biomicroscopy scans of the mouse skull. The new approach holds great potential to provide better insights into cerebrovascular function and facilitate efficient studies into neurological and vascular abnormalities of the brain. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Kub5-Hera, the human Rtt103 homolog, plays dual functional roles in transcription termination and DNA repair

    PubMed Central

    Morales, Julio C.; Richard, Patricia; Rommel, Amy; Fattah, Farjana J.; Motea, Edward A.; Patidar, Praveen L.; Xiao, Ling; Leskov, Konstantin; Wu, Shwu-Yuan; Hittelman, Walter N.; Chiang, Cheng-Ming; Manley, James L.; Boothman, David A.

    2014-01-01

    Functions of Kub5-Hera (In Greek Mythology Hera controlled Artemis) (K-H), the human homolog of the yeast transcription termination factor Rtt103, remain undefined. Here, we show that K-H has functions in both transcription termination and DNA double-strand break (DSB) repair. K-H forms distinct protein complexes with factors that repair DSBs (e.g. Ku70, Ku86, Artemis) and terminate transcription (e.g. RNA polymerase II). K-H loss resulted in increased basal R-loop levels, DSBs, activated DNA-damage responses and enhanced genomic instability. Significantly lowered Artemis protein levels were detected in K-H knockdown cells, which were restored with specific K-H cDNA re-expression. K-H deficient cells were hypersensitive to cytotoxic agents that induce DSBs, unable to reseal complex DSB ends, and showed significantly delayed γ-H2AX and 53BP1 repair-related foci regression. Artemis re-expression in K-H-deficient cells restored DNA-repair function and resistance to DSB-inducing agents. However, R loops persisted consistent with dual roles of K-H in transcription termination and DSB repair. PMID:24589584

  14. Kub5-Hera, the human Rtt103 homolog, plays dual functional roles in transcription termination and DNA repair.

    PubMed

    Morales, Julio C; Richard, Patricia; Rommel, Amy; Fattah, Farjana J; Motea, Edward A; Patidar, Praveen L; Xiao, Ling; Leskov, Konstantin; Wu, Shwu-Yuan; Hittelman, Walter N; Chiang, Cheng-Ming; Manley, James L; Boothman, David A

    2014-04-01

    Functions of Kub5-Hera (In Greek Mythology Hera controlled Artemis) (K-H), the human homolog of the yeast transcription termination factor Rtt103, remain undefined. Here, we show that K-H has functions in both transcription termination and DNA double-strand break (DSB) repair. K-H forms distinct protein complexes with factors that repair DSBs (e.g. Ku70, Ku86, Artemis) and terminate transcription (e.g. RNA polymerase II). K-H loss resulted in increased basal R-loop levels, DSBs, activated DNA-damage responses and enhanced genomic instability. Significantly lowered Artemis protein levels were detected in K-H knockdown cells, which were restored with specific K-H cDNA re-expression. K-H deficient cells were hypersensitive to cytotoxic agents that induce DSBs, unable to reseal complex DSB ends, and showed significantly delayed γ-H2AX and 53BP1 repair-related foci regression. Artemis re-expression in K-H-deficient cells restored DNA-repair function and resistance to DSB-inducing agents. However, R loops persisted consistent with dual roles of K-H in transcription termination and DSB repair.

  15. Peroxiredoxin 1 (Prx1) is a dual-function enzyme by possessing Cys-independent catalase-like activity

    PubMed Central

    Sun, Cen-Cen; Dong, Wei-Ren; Shao, Tong; Li, Jiang-Yuan; Zhao, Jing; Nie, Li

    2017-01-01

    Peroxiredoxin (Prx) was previously known as a Cys-dependent thioredoxin. However, we unexpectedly observed that Prx1 from the green spotted puffer fish Tetraodon nigroviridis (TnPrx1) was able to reduce H2O2 in a manner independent of Cys peroxidation and reductants. This study aimed to validate a novel function for Prx1, delineate the biochemical features and explore its antioxidant role in cells. We have confirmed that Prx1 from the puffer fish and humans truly possesses a catalase (CAT)-like activity that is independent of Cys residues and reductants, but dependent on iron. We have identified that the GVL motif was essential to the CAT-like activity of Prx1, but not to the Cys-dependent thioredoxin peroxidase (POX) activity, and generated mutants lacking POX and/or CAT-like activities for individual functional validation. We discovered that the TnPrx1 POX and CAT-like activities possessed different kinetic features in the reduction of H2O2. The overexpression of wild-type TnPrx1 and mutants differentially regulated the intracellular levels of reactive oxygen species (ROS) and the phosphorylation of p38 in HEK-293T cells treated with H2O2. Prx1 is a dual-function enzyme by acting as POX and CAT with varied affinities towards ROS. This study extends our knowledge on Prx1 and provides new opportunities to further study the biological roles of this family of antioxidants. PMID:28219939

  16. Traits, properties, and performance: how woody plants combine hydraulic and mechanical functions in a cell, tissue, or whole plant.

    PubMed

    Lachenbruch, Barbara; McCulloh, Katherine A

    2014-12-01

    This review presents a framework for evaluating how cells, tissues, organs, and whole plants perform both hydraulic and mechanical functions. The morphological alterations that affect dual functionality are varied: individual cells can have altered morphology; tissues can have altered partitioning to functions or altered cell alignment; and organs and whole plants can differ in their allocation to different tissues, or in the geometric distribution of the tissues they have. A hierarchical model emphasizes that morphological traits influence the hydraulic or mechanical properties; the properties, combined with the plant unit's environment, then influence the performance of that plant unit. As a special case, we discuss the mechanisms by which the proxy property wood density has strong correlations to performance but without direct causality. Traits and properties influence multiple aspects of performance, and there can be mutual compensations such that similar performance occurs. This compensation emphasizes that natural selection acts on, and a plant's viability is determined by, its performance, rather than its contributing traits and properties. Continued research on the relationships among traits, and on their effects on multiple aspects of performance, will help us better predict, manage, and select plant material for success under multiple stresses in the future. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  17. A dual-function fluorescent probe for monitoring the degrees of hypoxia in living cells via the imaging of nitroreductase and adenosine triphosphate.

    PubMed

    Fang, Yu; Shi, Wen; Hu, Yiming; Li, Xiaohua; Ma, Huimin

    2018-05-24

    A new dual-function fluorescent probe is developed for detecting nitroreductase (NTR) and adenosine triphosphate (ATP) with different responses. Imaging application of the probe reveals that intracellular NTR and ATP display an adverse changing trend during a hypoxic process and ATP can serve as a new sign for cell hypoxia.

  18. Examining Preschool-Aged Dual Language Learners' Language Use: From a Functional Approach. WCER Working Paper No. 2016-1

    ERIC Educational Resources Information Center

    Kim, Ahyoung Alicia; Kondo, Akira; Castro, Mariana

    2016-01-01

    Due to the increase in the number of preschool-aged dual language learners (DLLs), there is a need to understand their language development and how to better support them. Although DLLs' language development has traditionally been studied from a structuralist perspective, few have examined their language use from a functional approach, which…

  19. Functional properties of honey supplemented with bee bread and propolis.

    PubMed

    Kowalski, S; Makarewicz, M

    2017-11-01

    The aim of this work was characterisation of functional properties of honey enriched with propolis and beebread. In first step of experiment, soft propolis extract (SPEx) was obtained by extraction of propolis with ethanol. SPEx (0.25 to 1.0% w/w) as well as beebread (5 to 15% w/w) were implemented into natural honey. Fortified honeys were investigated in terms of total phenolic content, radical scavenging activity and ferric reducing antioxidant power, also their effects on the micro-organisms growth was examined. It was found that beebread had the most significant influence on antioxidant properties. On the other hand, all tested honeys showed antibacterial activity against Escherichia coli but not against Micrococcus luteus. Honeys with 1% of propolis addition were the most effective in this case. Research has indicated that for antioxidant and antimicrobial properties of honey, it is beneficial to enrich it in both beebread and propolis.

  20. Dual function of active constituents from bark of Ficus racemosa L in wound healing.

    PubMed

    Bopage, Nisansala Swarnamali; Kamal Bandara Gunaherath, G M; Jayawardena, Kithsiri Hector; Wijeyaratne, Sushila Chandrani; Abeysekera, Ajita Mahendra; Somaratne, Seneviratne

    2018-01-25

    chemical constituents present in stem bark of Ficus racemosa L show enhancement of cell migration (which corresponds to the cell proliferation) as well as antimicrobial activity. This dual action of F. racemosa stem bark provides scientific support for its traditional use in wound healing.

  1. Nitrate source apportionment using a combined dual isotope, chemical and bacterial property, and Bayesian model approach in river systems

    NASA Astrophysics Data System (ADS)

    Xia, Yongqiu; Li, Yuefei; Zhang, Xinyu; Yan, Xiaoyuan

    2017-01-01

    Nitrate (NO3-) pollution is a serious problem worldwide, particularly in countries with intensive agricultural and population activities. Previous studies have used δ15N-NO3- and δ18O-NO3- to determine the NO3- sources in rivers. However, this approach is subject to substantial uncertainties and limitations because of the numerous NO3- sources, the wide isotopic ranges, and the existing isotopic fractionations. In this study, we outline a combined procedure for improving the determination of NO3- sources in a paddy agriculture-urban gradient watershed in eastern China. First, the main sources of NO3- in the Qinhuai River were examined by the dual-isotope biplot approach, in which we narrowed the isotope ranges using site-specific isotopic results. Next, the bacterial groups and chemical properties of the river water were analyzed to verify these sources. Finally, we introduced a Bayesian model to apportion the spatiotemporal variations of the NO3- sources. Denitrification was first incorporated into the Bayesian model because denitrification plays an important role in the nitrogen pathway. The results showed that fertilizer contributed large amounts of NO3- to the surface water in traditional agricultural regions, whereas manure effluents were the dominant NO3- source in intensified agricultural regions, especially during the wet seasons. Sewage effluents were important in all three land uses and exhibited great differences between the dry season and the wet season. This combined analysis quantitatively delineates the proportion of NO3- sources from paddy agriculture to urban river water for both dry and wet seasons and incorporates isotopic fractionation and uncertainties in the source compositions.

  2. Effects of milling on functional properties of rice flour.

    PubMed

    Kadan, R S; Bryant, R J; Miller, J A

    2008-05-01

    A commercial long-grain rice flour (CRF) and the flours made by using a pin mill and the Udy mill from the same batch of broken second-head white long-grain rice were evaluated for their particle size and functional properties. The purpose of this study was to compare the commercial rice flour milling method to the pin and Udy milling methods used in our laboratory and pilot plant. The results showed that pin milled flour had more uniform particle size than the other 2 milled flours. The chalky kernels found in broken white milled rice were pulverized more into fines in both Udy milled flour and CRF than in the pin milled flour. The excessive amount of fines in flours affected their functional properties, for example, WSI and their potential usage in the novel foods such as rice breads (RB). The RB made from CRF collapsed more than loaves made from pin milled Cypress long-grain flours.

  3. Pharmacological Properties of Melanin and its Function in Health.

    PubMed

    ElObeid, Adila Salih; Kamal-Eldin, Afaf; Abdelhalim, Mohamed Anwar K; Haseeb, Adil M

    2017-06-01

    The biological pigment melanin is present in most of the biological systems. It manifests a host of biological and pharmacological properties. Its role as a molecule with special properties and functions affecting general health, including photoprotective and immunological action, are well recognized. Its antioxidant, anti-inflammatory, immunomodulatory, radioprotective, hepatic, gastrointestinal and hypoglycaemic benefits have only recently been recognized and studied. It is also associated with certain disorders of the nervous system. In this MiniReview, we consider the steadily increasing literature on the bioavailability and functional activity of melanin. Published literature shows that melanin may play a number of possible pharmacological effects such as protective, stimulatory, diagnostic and curative roles in human health. In this MiniReview, possible health roles and pharmacological effects are considered. © 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  4. Emergence of binocular functional properties in a monocular neural circuit

    PubMed Central

    Ramdya, Pavan; Engert, Florian

    2010-01-01

    Sensory circuits frequently integrate converging inputs while maintaining precise functional relationships between them. For example, in mammals with stereopsis, neurons at the first stages of binocular visual processing show a close alignment of receptive-field properties for each eye. Still, basic questions about the global wiring mechanisms that enable this functional alignment remain unanswered, including whether the addition of a second retinal input to an otherwise monocular neural circuit is sufficient for the emergence of these binocular properties. We addressed this question by inducing a de novo binocular retinal projection to the larval zebrafish optic tectum and examining recipient neuronal populations using in vivo two-photon calcium imaging. Notably, neurons in rewired tecta were predominantly binocular and showed matching direction selectivity for each eye. We found that a model based on local inhibitory circuitry that computes direction selectivity using the topographic structure of both retinal inputs can account for the emergence of this binocular feature. PMID:19160507

  5. Novel dual ligand co-functionalized fluorescent gold nanoclusters as a versatile probe for sensitive analysis of Hg(2+) and oxytetracycline.

    PubMed

    Xu, Shenghao; Li, Xiaolin; Mao, Yaning; Gao, Teng; Feng, Xiuying; Luo, Xiliang

    2016-04-01

    In this work, we present a direct one-step strategy for rapidly preparing dual ligand co-functionalized fluorescent Au nanoclusters (NCs) by using threonine (Thr) and 11-mercaptoundecanoic acid (MUA) as assorted reductants and capping agents in aqueous solution at room temperature. Fluorescence spectra, high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), and infrared (IR) spectroscopy were performed to demonstrate the optical properties and chemical composition of the as-prepared AuNCs. They possess many attractive features such as near-infrared emission (λem = 606 nm), a large Stoke's shift (>300 nm), high colloidal stability (pH, temperature, salt, and time stability), and water dispersibility. Subsequently, the as-prepared AuNCs were used as a versatile probe for "turn off" sensing of Hg(2+) based on aggregation-induced fluorescence quenching and for "turn-on" sensing of oxytetracycline (OTC). This assay provided good linearity ranging from 37.5 to 3750 nM for Hg(2+) and from 0.375 to 12.5 μM for OTC, with detection limits of 8.6 nM and 0.15 μM, respectively. Moreover, the practical application of this assay was further validated by detecting OTC in human serum samples.

  6. Dual-Functionalized Graphene Oxide Based siRNA Delivery System for Implant Surface Biomodification with Enhanced Osteogenesis.

    PubMed

    Zhang, Li; Zhou, Qing; Song, Wen; Wu, Kaimin; Zhang, Yumei; Zhao, Yimin

    2017-10-11

    Surface functionalization by small interfering RNA (siRNA) is a novel strategy for improved implant osseointegration. A gene delivery system with safety and high transfection activity is a crucial factor for an siRNA-functionalized implant to exert its biological function. To this end, polyethylene glycol (PEG) and polyethylenimine (PEI) dual-functionalized graphene oxide (GO; nGO-PEG-PEI) may present a promising siRNA vector. In this study, nanosized nGO-PEG-PEI was prepared and optimized for siRNA delivery. Titania nanotubes (NTs) fabricated by anodic oxidation were biomodified with nGO-PEG-PEI/siRNA by cathodic electrodeposition, designated as NT-GPP/siRNA. NT-GPP/siRNA possessed benign cytocompatibility, as evaluated by cell adhesion and proliferation. Cellular uptake and knockdown efficiency of the NT-GPP/siRNA were assessed by MC3T3-E1 cells, which exhibited high siRNA delivery efficiency and sustained target gene silencing. Casein kinase-2 interacting protein-1 (Ckip-1) is a negative regulator of bone formation. siRNA-targeting Ckip-1 (siCkip-1) was introduced to the implant, and a series of in vitro and in vivo experiments were carried out to evaluate the osteogenic capacity of NT-GPP/siCkip-1. NT-GPP/siCkip-1 dramatically improved the in vitro osteogenic differentiation of MC3T3-E1 cells in terms of improved osteogenesis-related gene expression, and increased alkaline phosphatase (ALP) production, collagen secretion, and extracellular matrix (ECM) mineralization. Moreover, NT-GPP/siCkip-1 led to apparently enhanced in vivo osseointegration, as indicated by histological staining and EDX line scanning. Collectively, these findings suggest that NT-GPP/siRNA represents a practicable and promising approach for implant functionalization, showing clinical potential for dental and orthopedic applications.

  7. Functional and technological properties of camel milk proteins: a review.

    PubMed

    Hailu, Yonas; Hansen, Egon Bech; Seifu, Eyassu; Eshetu, Mitiku; Ipsen, Richard; Kappeler, Stefan

    2016-11-01

    This review summarises current knowledge on camel milk proteins, with focus on significant peculiarities in protein composition and molecular properties. Camel milk is traditionally consumed as a fresh or naturally fermented product. Within the last couple of years, an increasing quantity is being processed in dairy plants, and a number of consumer products have been marketed. A better understanding of the technological and functional properties, as required for product improvement, has been gained in the past years. Absence of the whey protein β-LG and a low proportion of к-casein cause differences in relation to dairy processing. In addition to the technological properties, there are also implications for human nutrition and camel milk proteins are of interest for applications in infant foods, for food preservation and in functional foods. Proposed health benefits include inhibition of the angiotensin converting enzyme, antimicrobial and antioxidant properties as well as an antidiabetogenic effect. Detailed investigations on foaming, gelation and solubility as well as technological consequences of processing should be investigated further for the improvement of camel milk utilisation in the near future.

  8. Some functional properties of composite material based on scrap tires

    NASA Astrophysics Data System (ADS)

    Plesuma, Renate; Malers, Laimonis

    2013-09-01

    The utilization of scrap tires still obtains a remarkable importance from the aspect of unloading the environment from non-degradable waste [1]. One of the most prospective ways for scrap tires reuse is a production of composite materials [2] This research must be considered as a continuation of previous investigations [3, 4]. It is devoted to the clarification of some functional properties, which are considered important for the view of practical applications, of the composite material. Some functional properties of the material were investigated, for instance, the compressive stress at different extent of deformation of sample (till 67% of initial thickness) (LVS EN 826) [5] and the resistance to UV radiation (modified method based on LVS EN 14836) [6]. Experiments were realized on the purposefully selected samples. The results were evaluated in the correlation with potential changes of Shore C hardness (Shore scale, ISO 7619-1, ISO 868) [7, 8]. The results showed noticeable resistance of the composite material against the mechanical influence and ultraviolet (UV) radiation. The correlation with the composition of the material, activity of binder, definite technological parameters, and the conditions supported during the production, were determined. It was estimated that selected properties and characteristics of the material are strongly dependent from the composition and technological parameters used in production of the composite material, and from the size of rubber crumb. Obtained results show possibility to attain desirable changes in the composite material properties by changing both the composition and technological parameters of examined material.

  9. Functional properties of Mozzarella cheese for its end use application.

    PubMed

    Ah, Jana; Tagalpallewar, Govind P

    2017-11-01

    Cheese is an extremely versatile food product that has a wide range of flavor, textures and end uses. The vast majority of cheese is eaten not by itself, but as part of another food. As an ingredient in foods, cheese is required to exhibit functional characteristics in the raw as well as cooked forms. Melting, stretching, free-oil formation, elasticity and browning are the functional properties considered to be significant for Mozzarella cheese. When a cheese is destined for its end use, some of its unique characteristics play a significant role in the products acceptability. For instance pH of cheese determines the cheese structure which in turn decides the cheese shredability and meltability properties. The residual galactose content in cheese mass determines the propensity of cheese to brown during baking. Development of 'tailor-made cheese' involves focusing on manipulation of such unique traits of cheese in order to obtain the desired characteristics for its end use application suiting the varied consumer's whims and wishes. This comprehensive review paper will provide an insight to the cheese maker regarding the factors determining the functional properties of cheese and also for the pizza manufacturers to decide which age of cheese to be used which will perform well in baking applications.

  10. Efficient Density Functional Approximation for Electronic Properties of Conjugated Systems

    NASA Astrophysics Data System (ADS)

    Caldas, Marília J.; Pinheiro, José Maximiano, Jr.; Blum, Volker; Rinke, Patrick

    2014-03-01

    There is on-going discussion about reliable prediction of electronic properties of conjugated oligomers and polymers, such as ionization potential IP and energy gap. Several exchange-correlation (XC) functionals are being used by the density functional theory community, with different success for different properties. In this work we follow a recent proposal: a fraction α of exact exchange is added to the semi-local PBE XC aiming consistency, for a given property, with the results obtained by many-body perturbation theory within the G0W0 approximation. We focus the IP, taken as the negative of the highest occupied molecular orbital energy. We choose α from a study of the prototype family trans-acetylene, and apply this same α to a set of oligomers for which there is experimental data available (acenes, phenylenes and others). Our results indicate we can have excellent estimates, within 0,2eV mean ave. dev. from the experimental values, better than through complete EN - 1 -EN calculations from the starting PBE functional. We also obtain good estimates for the electrical gap and orbital energies close to the band edge. Work supported by FAPESP, CNPq, and CAPES, Brazil, and DAAD, Germany.

  11. Luminescence Properties of Self-Aggregating TbIII-DOTA-Functionalized Calix[4]arenes

    NASA Astrophysics Data System (ADS)

    Mayer, Florian; Tiruvadi Krishnan, Sriram; Schühle, Daniel T.; Eliseeva, Svetlana V.; Petoud, Stéphane; Tóth, Éva; Djanashvili, Kristina

    2018-01-01

    Self-aggregating calix[4]arenes carrying four DOTA ligands on the upper rim for stable complexation of paramagnetic GdIII-ions have already been proposed as MRI probes. In this work, we investigate the luminescence properties of TbIII-DOTA-calix[4]arene-4OPr containing four propyl-groups and compare them with those of the analogue substituted with a phthalimide chromophore (TbIII-DOTA-calix[4]arene-3OPr-OPhth). We show that, given its four aromatic rings, the calix[4]arene core acts as an effective sensitizer of Tb-centered luminescence. Substituents on the lower rim can modulate the aggregation behavior, which in turn determines the luminescence properties of the compounds. In solid state, the quantum yield of the phthalimide derivative is almost three times as high as that of the propyl-functionalized analogue demonstrating a beneficial role of the chromophore on Tb-luminescence. In solution, however, the effect of the phthalimide group vanishes, which we attribute to the large distance between the chromophore and the lanthanide, situated on the opposite rims of the calix[4]arene. Both quantum yields and luminescence lifetimes show clear concentration dependence in solution, related to the strong impact of aggregation on the luminescence behaviour. We also evidence the variability in the values of the critical micelle concentration depending on the experimental technique. Such luminescent calix[4]arene platforms accommodating stable lanthanide complexes can be considered valuable building blocks for the design of dual MR/optical imaging probes.

  12. Luminescence Properties of Self-Aggregating TbIII-DOTA-Functionalized Calix[4]arenes.

    PubMed

    Mayer, Florian; Tiruvadi Krishnan, Sriram; Schühle, Daniel T; Eliseeva, Svetlana V; Petoud, Stéphane; Tóth, Éva; Djanashvili, Kristina

    2018-01-01

    Self-aggregating calix[4]arenes carrying four DOTA ligands on the upper rim for stable complexation of paramagnetic Gd III -ions have already been proposed as MRI probes. In this work, we investigate the luminescence properties of Tb III -DOTA-calix[4]arene-4OPr containing four propyl-groups and compare them with those of the analog substituted with a phthalimide chromophore (Tb III -DOTA-calix[4]arene-3OPr-OPhth). We show that, given its four aromatic rings, the calix[4]arene core acts as an effective sensitizer of Tb-centered luminescence. Substituents on the lower rim can modulate the aggregation behavior, which in turn determines the luminescence properties of the compounds. In solid state, the quantum yield of the phthalimide derivative is almost three times as high as that of the propyl-functionalized analog demonstrating a beneficial role of the chromophore on Tb-luminescence. In solution, however, the effect of the phthalimide group vanishes, which we attribute to the large distance between the chromophore and the lanthanide, situated on the opposite rims of the calix[4]arene. Both quantum yields and luminescence lifetimes show clear concentration dependence in solution, related to the strong impact of aggregation on the luminescence behavior. We also evidence the variability in the values of the critical micelle concentration depending on the experimental technique. Such luminescent calix[4]arene platforms accommodating stable lanthanide complexes can be considered valuable building blocks for the design of dual MR/optical imaging probes.

  13. Dual function of the UNC-45b chaperone with myosin and GATA4 in cardiac development

    PubMed Central

    Chen, Daisi; Li, Shumin; Singh, Ram; Spinette, Sarah; Sedlmeier, Reinhard; Epstein, Henry F.

    2012-01-01

    Summary Cardiac development requires interplay between the regulation of gene expression and the assembly of functional sarcomeric proteins. We report that UNC-45b recessive loss-of-function mutations in C3H and C57BL/6 inbred mouse strains cause arrest of cardiac morphogenesis at the formation of right heart structures and failure of contractile function. Wild-type C3H and C57BL/6 embryos at the same stage, E9.5, form actively contracting right and left atria and ventricles. The known interactions of UNC-45b as a molecular chaperone are consistent with diminished accumulation of the sarcomeric myosins, but not their mRNAs, and the resulting decreased contraction of homozygous mutant embryonic hearts. The novel finding that GATA4 accumulation is similarly decreased at the protein but not mRNA levels is also consistent with the function of UNC-45b as a chaperone. The mRNAs of known downstream targets of GATA4 during secondary cardiac field development, the cardiogenic factors Hand1, Hand2 and Nkx-2.5, are also decreased, consistent with the reduced GATA4 protein accumulation. Direct binding studies show that the UNC-45b chaperone forms physical complexes with both the alpha and beta cardiac myosins and the cardiogenic transcription factor GATA4. Co-expression of UNC-45b with GATA4 led to enhanced transcription from GATA promoters in naïve cells. These novel results suggest that the heart-specific UNC-45b isoform functions as a molecular chaperone mediating contractile function of the sarcomere and gene expression in cardiac development. PMID:22553207

  14. Simultaneous dual-functioning InGaN/GaN multiple-quantum-well diode for transferrable optoelectronics

    NASA Astrophysics Data System (ADS)

    Shi, Zheng; Yuan, Jialei; Zhang, Shuai; Liu, Yuhuai; Wang, Yongjin

    2017-10-01

    We propose a wafer-level procedure for the fabrication of 1.5-mm-diameter dual functioning InGaN/GaN multiple-quantum-well (MQW) diodes on a GaN-on-silicon platform for transferrable optoelectronics. Nitride semiconductor materials are grown on (111) silicon substrates with intermediate Al-composition step-graded buffer layers, and membrane-type MQW-diode architectures are obtained by a combination of silicon removal and III-nitride film backside thinning. Suspended MQW-diodes are directly transferred from silicon to foreign substrates such as metal, glass and polyethylene terephthalate by mechanically breaking the support beams. The transferred MQW-diodes display strong electroluminescence under current injection and photodetection under light irradiation. Interestingly, they demonstrate a simultaneous light-emitting light-detecting function, endowing the 1.5-mm-diameter MQW-diode with the capability of producing transferrable optoelectronics for adjustable displays, wearable optical sensors, multifunctional energy harvesting, flexible light communication and monolithic photonic circuit.

  15. Dual function of Rpn5 in two PCI complexes, the 26S proteasome and COP9 signalosome.

    PubMed

    Yu, Zanlin; Kleifeld, Oded; Lande-Atir, Avigail; Bsoul, Maisa; Kleiman, Maya; Krutauz, Daria; Book, Adam; Vierstra, Richard D; Hofmann, Kay; Reis, Noa; Glickman, Michael H; Pick, Elah

    2011-04-01

    Subunit composition and architectural structure of the 26S proteasome lid is strictly conserved between all eukaryotes. This eight-subunit complex bears high similarity to the eukaryotic translation initiation factor 3 and to the COP9 signalosome (CSN), which together define the proteasome CSN/COP9/initiation factor (PCI) troika. In some unicellular eukaryotes, the latter two complexes lack key subunits, encouraging questions about the conservation of their structural design. Here we demonstrate that, in Saccharomyces cerevisiae, Rpn5 plays dual roles by stabilizing proteasome and CSN structures independently. Proteasome and CSN complexes are easily dissected, with Rpn5 the only subunit in common. Together with Rpn5, we identified a total of six bona fide subunits at roughly stoichiometric ratios in isolated, affinity-purified CSN. Moreover, the copy of Rpn5 associated with the CSN is required for enzymatic hydrolysis of Rub1/Nedd8 conjugated to cullins. We propose that multitasking by a single subunit, Rpn5 in this case, allows it to function in different complexes simultaneously. These observations demonstrate that functional substitution of subunits by paralogues is feasible, implying that the canonical composition of the three PCI complexes in S. cerevisiae is more robust than hitherto appreciated.

  16. Functional Assessment of Disease-Associated Regulatory Variants In Vivo Using a Versatile Dual Colour Transgenesis Strategy in Zebrafish

    PubMed Central

    Bhatia, Shipra; Gordon, Christopher T.; Foster, Robert G.; Melin, Lucie; Abadie, Véronique; Baujat, Geneviève; Vazquez, Marie-Paule; Amiel, Jeanne; Lyonnet, Stanislas; van Heyningen, Veronica; Kleinjan, Dirk A.

    2015-01-01

    Disruption of gene regulation by sequence variation in non-coding regions of the genome is now recognised as a significant cause of human disease and disease susceptibility. Sequence variants in cis-regulatory elements (CREs), the primary determinants of spatio-temporal gene regulation, can alter transcription factor binding sites. While technological advances have led to easy identification of disease-associated CRE variants, robust methods for discerning functional CRE variants from background variation are lacking. Here we describe an efficient dual-colour reporter transgenesis approach in zebrafish, simultaneously allowing detailed in vivo comparison of spatio-temporal differences in regulatory activity between putative CRE variants and assessment of altered transcription factor binding potential of the variant. We validate the method on known disease-associated elements regulating SHH, PAX6 and IRF6 and subsequently characterise novel, ultra-long-range SOX9 enhancers implicated in the craniofacial abnormality Pierre Robin Sequence. The method provides a highly cost-effective, fast and robust approach for simultaneously unravelling in a single assay whether, where and when in embryonic development a disease-associated CRE-variant is affecting its regulatory function. PMID:26030420

  17. Galline Ex-FABP is an Antibacterial Siderocalin and a Lysophosphatidic Acid Sensor Functioning through Dual Ligand Specificities

    PubMed Central

    Correnti, Colin; Clifton, Matthew C.; Abergel, Rebecca J.; Allred, Ben; Hoette, Trisha M.; Ruiz, Mario; Cancedda, Ranieri; Raymond, Kenneth N.; Descalzi, Fiorella; Strong, Roland K.

    2011-01-01

    SUMMARY Galline Ex-FABP was identified as another candidate antibacterial, catecholate siderophore binding lipocalin (siderocalin) based on structural parallels with the family archetype, mammalian Siderocalin. Binding assays show that Ex-FABP retains iron in a siderophore-dependent manner in both hypertrophic and dedifferentiated chondrocytes, where Ex-FABP expression is induced after treatment with proinflammatory agents, and specifically binds ferric complexes of enterobactin, parabactin, bacillibactin and, unexpectedly, monoglucosylated enterobactin, which does not bind to Siderocalin. Growth arrest assays functionally confirm the bacteriostatic effect of Ex-FABP in vitro under iron-limiting conditions. The 1.8Å crystal structure of Ex-FABP explains the expanded specificity, but also surprisingly reveals an extended, multi-chambered cavity extending through the protein and encompassing two separate ligand specificities, one for bacterial siderophores (as in Siderocalin) at one end and one specifically binding co-purified lysophosphatidic acid, a potent cell signaling molecule, at the other end, suggesting Ex-FABP employs dual functionalities to explain its diverse endogenous activities. PMID:22153502

  18. The Dual Function of "usted:" Forms of Address in Bogota, Colombia.

    ERIC Educational Resources Information Center

    Uber, Diane Ringer

    1985-01-01

    Shows that "usted" has two functions: showing lack of solidarity and showing extreme solidarity, with "tu" falling somewhere in between on the continuum. Discusses the increasing use of "tu," especially among younger people, and presents some possible reasons for this. (SED)

  19. The dual function of barred plumage in birds: camouflage and communication.

    PubMed

    Gluckman, T L; Cardoso, G C

    2010-11-01

    A commonly held principle in visual ecology is that communication compromises camouflage: while visual signals are often conspicuous, camouflage provides concealment. However, some traits may have evolved for communication and camouflage simultaneously, thereby overcoming this functional compromise. Visual patterns generally provide camouflage, but it was suggested that a particular type of visual pattern – avian barred plumage – could also be a signal of individual quality. Here, we test if the evolution of sexual dimorphism in barred plumage, as well as differences between juvenile and adult plumage, indicate camouflage and/or signalling functions across the class Aves. We found a higher frequency of female- rather than male-biased sexual dimorphism in barred plumage, indicating that camouflage is its most common function. But we also found that, compared to other pigmentation patterns, barred plumage is more frequently biased towards males and its expression more frequently restricted to adulthood, suggesting that barred plumage often evolves or is maintained as a sexual communication signal. This illustrates how visual traits can accommodate the apparently incompatible functions of camouflage and communication, which has implications for our understanding of avian visual ecology and sexual ornamentation.

  20. Functional synthetic Antennapedia genes and the dual roles of YPWM motif and linker size in transcriptional activation and repression

    PubMed Central

    Papadopoulos, Dimitrios K.; Reséndez-Pérez, Diana; Cárdenas-Chávez, Diana L.; Villanueva-Segura, Karina; Canales-del-Castillo, Ricardo; Felix, Daniel A.; Fünfschilling, Raphael; Gehring, Walter J.

    2011-01-01

    Segmental identity along the anteroposterior axis of bilateral animals is specified by Hox genes. These genes encode transcription factors, harboring the conserved homeodomain and, generally, a YPWM motif, which binds Hox cofactors and increases Hox transcriptional specificity in vivo. Here we derive synthetic Drosophila Antennapedia genes, consisting only of the YPWM motif and homeodomain, and investigate their functional role throughout development. Synthetic peptides and full-length Antennapedia proteins cause head-to-thorax transformations in the embryo, as well as antenna-to-tarsus and eye-to-wing transformations in the adult, thus converting the entire head to a mesothorax. This conversion is achieved by repression of genes required for head and antennal development and ectopic activation of genes promoting thoracic and tarsal fates, respectively. Synthetic Antennapedia peptides bind DNA specifically and interact with Extradenticle and Bric-à-brac interacting protein 2 cofactors in vitro and ex vivo. Substitution of the YPWM motif by alanines abolishes Antennapedia homeotic function, whereas substitution of YPWM by the WRPW repressor motif, which binds the transcriptional corepressor Groucho, allows all proteins to act as repressors only. Finally, naturally occurring variations in the size of the linker between the homeodomain and YPWM motif enhance Antennapedia repressive or activating efficiency, emphasizing the importance of linker size, rather than sequence, for specificity. Our results clearly show that synthetic Antennapedia genes are functional in vivo and therefore provide powerful tools for synthetic biology. Moreover, the YPWM motif is necessary—whereas the entire N terminus of the protein is dispensable—for Antennapedia homeotic function, indicating its dual role in transcriptional activation and repression by recruiting either coactivators or corepressors. PMID:21712439

  1. Polyethylene glycol and octa-arginine dual-functionalized nanographene oxide: an optimization for efficient nucleic acid delivery.

    PubMed

    Imani, Rana; Prakash, Satya; Vali, Hojatollah; Faghihi, Shahab

    2018-05-29

    The successful application of nucleic acid-based therapy for the treatment of various cancers is largely dependent on a safe and efficient delivery system. A dual-functionalized graphene oxide (GO)-based nanocarrier with the conjugation of aminated-polyethylene glycol (PEG-diamine) and octa-arginine (R8) for the intracellular delivery of nucleic acids is proposed. The functionalized sites are covalently co-conjugated and the PEG : R8 molar ratio is optimized at 10 : 1 to achieve a hydrocolloidally stable size of 252 ± 2.0 nm with an effective charge of +40.97 ± 1.05 and an amine-rich content of 10.87 ± 0.4 μmol g-1. The uptake of the nanocarrier in breast cancer cell lines, MCF-7 and MDA-MB 231, is investigated. The siRNA and pDNA condensation ability in the presence and absence of enzymes and the endosomal buffering capacity, as well as the intracellular localization of the gene/nanocarrier complex are also evaluated. Furthermore, the delivery of functional genes associated with the nanocarrier is assessed using c-Myc protein knockdown and EGFP gene expression. The effective uptake of the nanocarrier by the cells shows superior cytocompatibility, and protects the siRNA and pDNA against enzyme degradation while inhibiting their migration with N : P ratios of 10 and 5, respectively. The co-conjugation of PEG-diamine and the cationic cell-penetrating peptide (CPP) into the GO nanocarrier also provides a superior internalization efficacy of 85% in comparison with a commercially available transfection reagent. The c-Myc protein knockdown and EGFP expression, which are induced by the nanocarrier, confirm that the optimized PEG-diamine/R8-functionalized GO could effectively deliver pDNA and siRNA into the cells and interfere with gene expression.

  2. Dual Functions of ASCIZ in the DNA Base Damage Response and Pulmonary Organogenesis

    PubMed Central

    Tenis, Nora; Hammet, Andrew; Hewitt, Kimberly; Ng, Jane-Lee; McNees, Carolyn J.; Kozlov, Sergei V.; Oka, Hayato; Kobayashi, Masahiko; Conlan, Lindus A.; Cole, Timothy J.; Yamamoto, Ken-ichi; Taniguchi, Yoshihito; Takeda, Shunichi; Lavin, Martin F.; Heierhorst, Jörg

    2010-01-01

    Zn2+-finger proteins comprise one of the largest protein superfamilies with diverse biological functions. The ATM substrate Chk2-interacting Zn2+-finger protein (ASCIZ; also known as ATMIN and ZNF822) was originally linked to functions in the DNA base damage response and has also been proposed to be an essential cofactor of the ATM kinase. Here we show that absence of ASCIZ leads to p53-independent late-embryonic lethality in mice. Asciz-deficient primary fibroblasts exhibit increased sensitivity to DNA base damaging agents MMS and H2O2, but Asciz deletion or knock-down does not affect ATM levels and activation in mouse, chicken, or human cells. Unexpectedly, Asciz-deficient embryos also exhibit severe respiratory tract defects with complete pulmonary agenesis and severe tracheal atresia. Nkx2.1-expressing respiratory precursors are still specified in the absence of ASCIZ, but fail to segregate properly within the ventral foregut, and as a consequence lung buds never form and separation of the trachea from the oesophagus stalls early. Comparison of phenotypes suggests that ASCIZ functions between Wnt2-2b/ß-catenin and FGF10/FGF-receptor 2b signaling pathways in the mesodermal/endodermal crosstalk regulating early respiratory development. We also find that ASCIZ can activate expression of reporter genes via its SQ/TQ-cluster domain in vitro, suggesting that it may exert its developmental functions as a transcription factor. Altogether, the data indicate that, in addition to its role in the DNA base damage response, ASCIZ has separate developmental functions as an essential regulator of respiratory organogenesis. PMID:20975950

  3. Use of internal scintillator radioactivity to calibrate DOI function of a PET detector with a dual-ended-scintillator readout

    PubMed Central

    Bircher, Chad; Shao, Yiping

    2012-01-01

    Purpose: Positron emission tomography (PET) detectors that use a dual-ended-scintillator readout to measure depth-of-interaction (DOI) must have an accurate DOI function to provide the relationship between DOI and signal ratios to be used for detector calibration and recalibration. In a previous study, the authors used a novel and simple method to accurately and quickly measure DOI function by irradiating the detector with an external uniform flood source; however, as a practical concern, implementing external uniform flood sources in an assembled PET system is technically challenging and expensive. In the current study, therefore, the authors investigated whether the same method could be used to acquire DOI function from scintillator-generated (i.e., internal) radiation. The authors also developed a method for calibrating the energy scale necessary to select the events within the desired energy window. Methods: The authors measured the DOI function of a PET detector with lutetium yttrium orthosilicate (LYSO) scintillators. Radiation events originating from the scintillators’ internal Lu-176 beta decay were used to measure DOI functions which were then compared with those measured from both an external uniform flood source and an electronically collimated external point source. The authors conducted these studies with several scintillators of differing geometries (1.5 × 1.5 and 2.0 × 2.0 mm2 cross-section area and 20, 30, and 40 mm length) and various surface finishes (mirror-finishing, saw-cut rough, and other finishes in between), and in a prototype array. Results: All measured results using internal and external radiation sources showed excellent agreement in DOI function measurement. The mean difference among DOI values for all scintillators measured from internal and external radiation sources was less than 1.0 mm for different scintillator geometries and various surface finishes. Conclusions: The internal radioactivity of LYSO scintillators can be

  4. Use of internal scintillator radioactivity to calibrate DOI function of a PET detector with a dual-ended-scintillator readout

    SciTech Connect

    Bircher, Chad; Shao Yiping

    Purpose: Positron emission tomography (PET) detectors that use a dual-ended-scintillator readout to measure depth-of-interaction (DOI) must have an accurate DOI function to provide the relationship between DOI and signal ratios to be used for detector calibration and recalibration. In a previous study, the authors used a novel and simple method to accurately and quickly measure DOI function by irradiating the detector with an external uniform flood source; however, as a practical concern, implementing external uniform flood sources in an assembled PET system is technically challenging and expensive. In the current study, therefore, the authors investigated whether the same method couldmore » be used to acquire DOI function from scintillator-generated (i.e., internal) radiation. The authors also developed a method for calibrating the energy scale necessary to select the events within the desired energy window. Methods: The authors measured the DOI function of a PET detector with lutetium yttrium orthosilicate (LYSO) scintillators. Radiation events originating from the scintillators' internal Lu-176 beta decay were used to measure DOI functions which were then compared with those measured from both an external uniform flood source and an electronically collimated external point source. The authors conducted these studies with several scintillators of differing geometries (1.5 x 1.5 and 2.0 x 2.0 mm{sup 2} cross-section area and 20, 30, and 40 mm length) and various surface finishes (mirror-finishing, saw-cut rough, and other finishes in between), and in a prototype array. Results: All measured results using internal and external radiation sources showed excellent agreement in DOI function measurement. The mean difference among DOI values for all scintillators measured from internal and external radiation sources was less than 1.0 mm for different scintillator geometries and various surface finishes. Conclusions: The internal radioactivity of LYSO scintillators can

  5. Use of internal scintillator radioactivity to calibrate DOI function of a PET detector with a dual-ended-scintillator readout.

    PubMed

    Bircher, Chad; Shao, Yiping

    2012-02-01

    Positron emission tomography (PET) detectors that use a dual-ended-scintillator readout to measure depth-of-interaction (DOI) must have an accurate DOI function to provide the relationship between DOI and signal ratios to be used for detector calibration and recalibration. In a previous study, the authors used a novel and simple method to accurately and quickly measure DOI function by irradiating the detector with an external uniform flood source; however, as a practical concern, implementing external uniform flood sources in an assembled PET system is technically challenging and expensive. In the current study, therefore, the authors investigated whether the same method could be used to acquire DOI function from scintillator-generated (i.e., internal) radiation. The authors also developed a method for calibrating the energy scale necessary to select the events within the desired energy window. The authors measured the DOI function of a PET detector with lutetium yttrium orthosilicate (LYSO) scintillators. Radiation events originating from the scintillators' internal Lu-176 beta decay were used to measure DOI functions which were then compared with those measured from both an external uniform flood source and an electronically collimated external point source. The authors conducted these studies with several scintillators of differing geometries (1.5 × 1.5 and 2.0 × 2.0 mm(2) cross-section area and 20, 30, and 40 mm length) and various surface finishes (mirror-finishing, saw-cut rough, and other finishes in between), and in a prototype array. All measured results using internal and external radiation sources showed excellent agreement in DOI function measurement. The mean difference among DOI values for all scintillators measured from internal and external radiation sources was less than 1.0 mm for different scintillator geometries and various surface finishes. The internal radioactivity of LYSO scintillators can be used to accurately measure DOI function

  6. Glutathione regulation-based dual-functional upconversion sensing-platform for acetylcholinesterase activity and cadmium ions.

    PubMed

    Fang, Aijin; Chen, Hongyu; Li, Haitao; Liu, Meiling; Zhang, Youyu; Yao, Shouzhuo

    2017-01-15

    A dual-functional platform for the sensing of acetylcholinesterase (AChE) activity and cadmium ions (Cd 2+ ) was developed based on the fluorescence resonance energy transfer (FRET) between NaYF 4 :Yb,Er upconversion nanoparticles (UCNPs) and gold nanoparticles (AuNPs) via glutathione regulation. The detection mechanism is based on the fact that AuNPs can quench the fluorescence of UCNPs. AChE catalyzes the hydrolysis of acetylthiocholine (ATC) into thiocholine which reacts with AuNPs by S-Au conjunction and results the aggregation of AuNPs and change in fluorescence of UCNPs. Therefore, the AChE activity can be detected through the changes of the color of solution and fluorescence recovery of UCNPs. However, the presence of glutathione (GSH) can protect AuNPs from aggregation and enlarge the inter-particle distance between AuNPs and UCNPs. When Cd 2+ is added into the stable mixture of AuNPs, GSH and AChE/ATC, Cd 2+ could interact with GSH to form a spherical shaped (GSH) 4 Cd complex, which decreases the free GSH on the surface of AuNPs to weaken the stability of AuNPs and lead to the easily aggregation of them in the system. The aggregated-AuNPs are released from the surface of UCNPs, which results in the fluorescence of UCNPs gradually recovered. Under the optimized conditions, the detection limits of AChE activity and Cd 2+ are estimated to be 0.015mU/mL and 0.2µM, respectively. The small molecules regulated dual-functional platform based on UCNPs/AuNPs is a simple, label-free method and can be applied for the turn-on fluorescence detection of AChE activity in human serum and Cd 2+ in real water samples. The present work demonstrates a general strategy for the design of small molecules regulated multifunctional platform and will be expanded for different areas in the future. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Magnetically triggered dual functional nanoparticles for resistance-free apoptotic hyperthermia.

    PubMed

    Yoo, Dongwon; Jeong, Heeyeong; Noh, Seung-Hyun; Lee, Jae-Hyun; Cheon, Jinwoo

    2013-12-02

    Overcoming resistance: Heat-treated cancer cells possess a protective mechanism for resistance and survival. Resistance-free apoptosis-inducing magnetic nanoparticles (RAINs) successfully promote hyperthermic apoptosis, obstructing cell survival by triggering two functional units of heat generation and the release of geldanamycin (GM) for heat shock protein (Hsp) inhibition under an alternating magnetic field (AMF). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Au Nanocage Functionalized with Ultra-small Fe3O4 Nanoparticles for Targeting T1-T2Dual MRI and CT Imaging of Tumor

    NASA Astrophysics Data System (ADS)

    Wang, Guannan; Gao, Wei; Zhang, Xuanjun; Mei, Xifan

    2016-06-01

    Diagnostic approaches based on multimodal imaging of clinical noninvasive imaging (eg. MRI/CT scanner) are highly developed in recent years for accurate selection of the therapeutic regimens in critical diseases. Therefore, it is highly demanded in the development of appropriate all-in-one multimodal contrast agents (MCAs) for the MRI/CT multimodal imaging. Here a novel ideal MCAs (F-AuNC@Fe3O4) were engineered by assemble Au nanocages (Au NC) and ultra-small iron oxide nanoparticles (Fe3O4) for simultaneous T1-T2dual MRI and CT contrast imaging. In this system, the Au nanocages offer facile thiol modification and strong X-ray attenuation property for CT imaging. The ultra-small Fe3O4 nanoparticles, as excellent contrast agent, is able to provide great enhanced signal of T1- and T2-weighted MRI (r1 = 6.263 mM-1 s-1, r2 = 28.117 mM-1 s-1) due to their ultra-refined size. After functionalization, the present MCAs nanoparticles exhibited small average size, low aggregation and excellent biocompatible. In vitro and In vivo studies revealed that the MCAs show long-term circulation time, renal clearance properties and outstanding capability of selective accumulation in tumor tissues for simultaneous CT imaging and T1- and T2-weighted MRI. Taken together, these results show that as-prepared MCAs are excellent candidates as MRI/CT multimodal imaging contrast agents.

  9. Dual Functional Roles of Molecular Beacon as a MicroRNA Detector and Inhibitor*

    PubMed Central

    Li, Wai Ming; Chan, Ching-Man; Miller, Andrew L.; Lee, Chow H.

    2017-01-01

    MicroRNAs are essential in many cellular processes. The ability to detect microRNAs is important for understanding its function and biogenesis. This study is aimed at using a molecular beacon to detect miR-430 in developing zebrafish embryos as a proof of principle. miR-430 is crucial for the clearance of maternal mRNA during maternal zygotic transition in embryonic development. Despite its known function, the temporal and spatial expression of miR-430 remains unclear. We used various imaging techniques, including laser scanning confocal microscopy, spinning disk, and lightsheet microscopy, to study the localization of miR-430 and any developmental defects possibly caused by the molecular beacon. Our results show that miR-430 is expressed early in development and is localized in distinct cytoplasmic granules where its target mRNA can be detected. We also show that the designed molecular beacon can inhibit the function of miR-430 and cause developmental defect in the brain, notochord, heart, and kidney, depending on the delivery site within the embryo, suggesting that miR-430 plays a diverse role in embryonic morphogenesis. When compared with morpholino, molecular beacon is 2 orders of magnitude more potent in inhibiting miR-430. Thus, our results reveal that in addition to being used as a valuable tool for the detection of microRNAs in vivo, molecular beacons can also be employed to inhibit microRNAs in a specific manner. PMID:28100783

  10. Akkermansia muciniphila: a novel functional microbe with probiotic properties.

    PubMed

    Gómez-Gallego, C; Pohl, S; Salminen, S; De Vos, W M; Kneifel, W

    2016-09-01

    Akkermansia muciniphila is an intestinal anaerobe which has been proposed as a new functional microbe with probiotic properties. However, the species is not included in the European Union qualified presumption of safety (QPS) list and has not yet been assessed. Moreover, products containing A. muciniphila are not on the market and are thus controlled by the Novel Foods Regulation, which requires extensive safety assessment. This review addresses the safety aspects of the use of A. muciniphila based on published information on its functions in humans and predictions based on its activity in model animals. Further, comprehensive studies related to A. muciniphila and its safety properties have gradually appeared and are summarised here. Many of the criteria required for novel food safety assessment in Europe can thus be fulfilled. However, studies focusing on the toxicological properties of A. muciniphila, including long-term and reproduction studies, have not so far been reported and are discussed in the light of the observation that most, if not all, healthy subjects are known to carry this intestinal anaerobe. As this also applies to other beneficial bacteria found in the human intestinal tract, the A. muciniphila case can be seen as a model for the comprehensive safety evaluations required by the European authorities.

  11. Optical properties (bidirectional reflectance distribution function) of shot fabric.

    PubMed

    Lu, R; Koenderink, J J; Kappers, A M

    2000-11-01

    To study the optical properties of materials, one needs a complete set of the angular distribution functions of surface scattering from the materials. Here we present a convenient method for collecting a large set of bidirectional reflectance distribution function (BRDF) samples in the hemispherical scattering space. Material samples are wrapped around a right-circular cylinder and irradiated by a parallel light source, and the scattered radiance is collected by a digital camera. We tilted the cylinder around its center to collect the BRDF samples outside the plane of incidence. This method can be used with materials that have isotropic and anisotropic scattering properties. We demonstrate this method in a detailed investigation of shot fabrics. The warps and the fillings of shot fabrics are dyed different colors so that the fabric appears to change color at different viewing angles. These color-changing characteristics are found to be related to the physical and geometrical structure of shot fabric. Our study reveals that the color-changing property of shot fabrics is due mainly to an occlusion effect.

  12. Diazonium functionalized graphene: microstructure, electric, and magnetic properties.

    PubMed

    Huang, Ping; Jing, Long; Zhu, Huarui; Gao, Xueyun

    2013-01-15

    The unique honeycomb lattice structure of graphene gives rise to its outstanding electronic properties such as ultrahigh carrier mobility, ballistic transport, and more. However, a crucial obstacle to its use in the electronics industry is its lack of an energy bandgap. A covalent chemistry strategy could overcome this problem, and would have the benefits of being highly controllable and stable in the ambient environment. One possible approach is aryl diazonium functionalization. In this Account, we investigate the micromolecular/lattice structure, electronic structure, and electron-transport properties of nitrophenyl-diazonium-functionalized graphene. We find that nitrophenyl groups mainly adopt random and inhomogeneous configurations on the graphene basal plane, and that their bonding with graphene carbon atoms leads to slight elongation of the graphene lattice spacing. By contrast, hydrogenated graphene has a compressed lattice. Low levels of functionalization suppressed the electric conductivity of the resulting functionalized graphene, while highly functionalized graphene showed the opposite effect. This difference arises from the competition between the charge transfer effect and the scattering enhancement effect introduced by nitrophenyl groups bonding with graphene carbon atoms. Detailed electron transport measurements revealed that the nitrophenyl diazonium functionalization locally breaks the symmetry of graphene lattice, which leads to an increase in the density of state near the Fermi level, thus increasing the carrier density. On the other hand, the bonded nitrophenyl groups act as scattering centers, lowering the mean free path of the charge carriers and suppressing the carrier mobility. In rare cases, we observed ordered configurations of nitrophenyl groups in local domains on graphene flakes due to fluctuations in the reaction processes. We describe one example of such a superlattice, with a lattice constant nearly twice of that of pristine graphene

  13. Dual Functional Roles of Molecular Beacon as a MicroRNA Detector and Inhibitor.

    PubMed

    Li, Wai Ming; Chan, Ching-Man; Miller, Andrew L; Lee, Chow H

    2017-03-03

    MicroRNAs are essential in many cellular processes. The ability to detect microRNAs is important for understanding its function and biogenesis. This study is aimed at using a molecular beacon to detect miR-430 in developing zebrafish embryos as a proof of principle. miR-430 is crucial for the clearance of maternal mRNA during maternal zygotic transition in embryonic development. Despite its known function, the temporal and spatial expression of miR-430 remains unclear. We used various imaging techniques, including laser scanning confocal microscopy, spinning disk, and lightsheet microscopy, to study the localization of miR-430 and any developmental defects possibly caused by the molecular beacon. Our results show that miR-430 is expressed early in development and is localized in distinct cytoplasmic granules where its target mRNA can be detected. We also show that the designed molecular beacon can inhibit the function of miR-430 and cause developmental defect in the brain, notochord, heart, and kidney, depending on the delivery site within the embryo, suggesting that miR-430 plays a diverse role in embryonic morphogenesis. When compared with morpholino, molecular beacon is 2 orders of magnitude more potent in inhibiting miR-430. Thus, our results reveal that in addition to being used as a valuable tool for the detection of microRNAs in vivo , molecular beacons can also be employed to inhibit microRNAs in a specific manner. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Dual function of the pectoral girdle for feeding and locomotion in white-spotted bamboo sharks.

    PubMed

    Camp, Ariel L; Scott, Bradley; Brainerd, Elizabeth L; Wilga, Cheryl D

    2017-07-26

    Positioned at the intersection of the head, body and forelimb, the pectoral girdle has the potential to function in both feeding and locomotor behaviours-although the latter has been studied far more. In ray-finned fishes, the pectoral girdle attaches directly to the skull and is retracted during suction feeding, enabling the ventral body muscles to power rapid mouth expansion. However, in sharks, the pectoral girdle is displaced caudally and entirely separate from the skull (as in tetrapods), raising the question of whether it is mobile during suction feeding and contributing to suction expansion. We measured three-dimensional kinematics of the pectoral girdle in white-spotted bamboo sharks during suction feeding with X-ray reconstruction of moving morphology, and found the pectoral girdle consistently retracted about 11° by rotating caudoventrally about the dorsal scapular processes. This motion occurred mostly after peak gape, so it likely contributed more to accelerating captured prey through the oral cavity and pharynx, than to prey capture as in ray-finned fishes. Our results emphasize the multiple roles of the pectoral girdle in feeding and locomotion, both of which should be considered in studying the functional and evolutionary morphology of this structure. © 2017 The Author(s).

  15. TRIM25 has a dual function in the p53/Mdm2 circuit.

    PubMed

    Zhang, P; Elabd, S; Hammer, S; Solozobova, V; Yan, H; Bartel, F; Inoue, S; Henrich, T; Wittbrodt, J; Loosli, F; Davidson, G; Blattner, C

    2015-11-12

    P53 is an important tumor suppressor that, upon activation, induces growth arrest and cell death. Control of p53 is thus of prime importance for proliferating cells, but also for cancer therapy, where p53 activity contributes to the eradication of tumors. Mdm2 functionally inhibits p53 and targets the tumor suppressor protein for degradation. In a genetic screen, we identified TRIM25 as a novel regulator of p53 and Mdm2. TRIM25 increased p53 and Mdm2 abundance by inhibiting their ubiquitination and degradation in 26 S proteasomes. TRIM25 co-precipitated with p53 and Mdm2 and interfered with the association of p300 and Mdm2, a critical step for p53 polyubiquitination. Despite the increase in p53 levels, p53 activity was inhibited in the presence of TRIM25. Downregulation of TRIM25 resulted in an increased acetylation of p53 and p53-dependent cell death in HCT116 cells. Upon genotoxic insults, TRIM25 dampened the p53-dependent DNA damage response. The downregulation of TRIM25 furthermore resulted in massive apoptosis during early embryogenesis of medaka, which was rescued by the concomitant downregulation of p53, demonstrating the functional relevance of the regulation of p53 by TRIM25 in an organismal context.

  16. Divergent metabolome and proteome suggest functional independence of dual phloem transport systems in cucurbits

    PubMed Central

    Zhang, Baichen; Tolstikov, Vladimir; Turnbull, Colin; Hicks, Leslie M.; Fiehn, Oliver

    2010-01-01

    Cucurbitaceous plants (cucurbits) have long been preferred models for studying phloem physiology. However, these species are unusual in that they possess two different phloem systems, one within the main vascular bundles [fascicular phloem (FP)] and another peripheral to the vascular bundles and scattered through stem and petiole cortex tissues [extrafascicular phloem (EFP)]. We have revisited the assumption that the sap released after shoot incision originates from the FP, and also investigated the long-standing question of why the sugar content of this sap is ~30-fold less than predicted for requirements of photosynthate delivery. Video microscopy and phloem labeling experiments unexpectedly reveal that FP very quickly becomes blocked upon cutting, whereas the extrafascicular phloem bleeds for extended periods. Thus, all cucurbit phloem sap studies to date have reported metabolite, protein, and RNA composition and transport in the relatively minor extrafascicular sieve tubes. Using tissue dissection and direct sampling of sieve tube contents, we show that FP in fact does contain up to 1 M sugars, in contrast to low-millimolar levels in the EFP. Moreover, major phloem proteins in sieve tubes of FP differ from those that predominate in the extrafascicular sap, and include several previously uncharacterized proteins with little or no homology to databases. The overall compositional differences of the two phloem systems strongly indicate functional isolation. On this basis, we propose that the fascicular phloem is largely responsible for sugar transport, whereas the extrafascicular phloem may function in signaling, defense, and transport of other metabolites. PMID:20566864

  17. Soil fauna, soil properties and geo-ecosystem functioning

    NASA Astrophysics Data System (ADS)

    Cammeraat, L. H.

    2012-04-01

    The impact of soil fauna on soil processes is of utmost importance, as the activity of soil fauna directly affects soil quality. This is expressed by the direct effects of soil fauna on soil physical and soil chemical properties that not only have great importance to food production and ecosystems services, but also on weathering and hydrological and geomorphological processes. Soil animals can be perceived as ecosystem engineers that directly affect the flow of water, sediments and nutrients through terrestrial ecosystems. The biodiversity of animals living in the soil is huge and shows a huge range in size, functions and effects. Most work has been focused on only a few species such as earthworms and termites, but in general the knowledge on the effect of soil biota on soil ecosystem functioning is limited as it is for their impact on processes in the soil and on the soil surface. In this presentation we would like to review some of the impacts of soil fauna on soil properties that have implications for geo-ecosystem functioning and soil formation processes.

  18. Optical, wetting and electrical properties of functionalized fulleropyrrolidine thin films

    NASA Astrophysics Data System (ADS)

    Abdulrazack, Parveen; Venkatesan, Sughanya; Chellasamy, Manoharan; Samuthira, Nagarajan

    2017-12-01

    Fulleropyrrolidine derivatives acts as an electron acceptor in the fabrication of solar cells and other optoelectronic devices. In this investigation thin film of functionalized fulleropyrrolidines were fabricated and studied their photo-physical properties. Surface morphology of the thin films was investigated through AFM and FE-SEM. The results suggested that large dependence on structure vs molecular packing. The long alkyl chain substituted C60 were assembled in the form of nanorods. C60- C60 intermolecular distance were measured, the films were with good absorption and exhibits n-type semiconducting behavior. The films were having high contact angle and can be effectively used for fabricating semiconducting devices with self- cleaning property.

  19. Dual Function Behavior of Carbon Fiber-Reinforced Polymer in Simulated Pore Solution

    PubMed Central

    Zhu, Ji-Hua; Guo, Guanping; Wei, Liangliang; Zhu, Miaochang; Chen, Xianchuan

    2016-01-01

    The mechanical and electrochemical performance of carbon fiber-reinforced polymer (CFRP) were investigated regarding a novel improvement in the load-carrying capacity and durability of reinforced concrete structures by adopting CFRP as both a structural strengthener and an anode of the impressed current cathodic protection (ICCP) system. The mechanical and anode performance of CFRP were investigated in an aqueous pore solution in which the electrolytes were available to the anode in a cured concrete structure. Accelerated polarization tests were designed with different test durations and various levels of applied currents in accordance with the international standard. The CFRP specimens were mechanically characterized after polarization. The measured feeding voltage and potential during the test period indicates CFRP have stable anode performance in a simulated pore solution. Two failure modes were observed through tensile testing. The tensile properties of the post-polarization CFRP specimens declined with an increased charge density. The CFRP demonstrated success as a structural strengthener and ICCP anode. We propose a mathematic model predicting the tensile strengths of CFRP with varied impressed charge densities. PMID:28787900

  20. Dual Function Behavior of Carbon Fiber-Reinforced Polymer in Simulated Pore Solution.

    PubMed

    Zhu, Ji-Hua; Guo, Guanping; Wei, Liangliang; Zhu, Miaochang; Chen, Xianchuan

    2016-02-06

    The mechanical and electrochemical performance of carbon fiber-reinforced polymer (CFRP) were investigated regarding a novel improvement in the load-carrying capacity and durability of reinforced concrete structures by adopting CFRP as both a structural strengthener and an anode of the impressed current cathodic protection (ICCP) system. The mechanical and anode performance of CFRP were investigated in an aqueous pore solution in which the electrolytes were available to the anode in a cured concrete structure. Accelerated polarization tests were designed with different test durations and various levels of applied currents in accordance with the international standard. The CFRP specimens were mechanically characterized after polarization. The measured feeding voltage and potential during the test period indicates CFRP have stable anode performance in a simulated pore solution. Two failure modes were observed through tensile testing. The tensile properties of the post-polarization CFRP specimens declined with an increased charge density. The CFRP demonstrated success as a structural strengthener and ICCP anode. We propose a mathematic model predicting the tensile strengths of CFRP with varied impressed charge densities.

  1. Dual-Functional Superhydrophobic Textiles with Asymmetric Roll-Down/Pinned States for Water Droplet Transportation and Oil-Water Separation.

    PubMed

    Su, Xiaojing; Li, Hongqiang; Lai, Xuejun; Zhang, Lin; Liao, Xiaofeng; Wang, Jing; Chen, Zhonghua; He, Jie; Zeng, Xingrong

    2018-01-31

    Superhydrophobic surfaces with tunable adhesion from lotus-leaf to rose-petal states have generated much attention for their potential applications in self-cleaning, anti-icing, oil-water separation, microdroplet transportation, and microfluidic devices. Herein we report a facile magnetic-field-manipulation strategy to fabricate dual-functional superhydrophobic textiles with asymmetric roll-down/pinned states on the two surfaces of the textile simultaneously. Upon exposure to a static magnetic field, fluoroalkylsilane-modified iron oxide (F-Fe 3 O 4 ) nanoparticles in polydimethylsiloxane (PDMS) moved along the magnetic field to construct discrepant hierarchical structures and roughnesses on the two sides of the textile. The positive surface (closer to the magnet, or P-surface) showed a water contact angle up to 165°, and the opposite surface (or O-surface) had a water contact angle of 152.5°. The P-surface where water droplets easily slid off with a sliding angle of 7.5° appeared in the "roll-down" state as Cassie mode, while the O-surface was in the "pinned" state as Wenzel mode, where water droplets firmly adhered even at vertical (90°) and inverted (180°) angles. The surface morphology and wetting mode were adjustable by varying the ratios of F-Fe 3 O 4 nanoparticles and PDMS. By taking advantage of the asymmetric adhesion behaviors, the as-fabricated superhydrophobic textile was successfully applied in no-loss microdroplet transportation and oil-water separation. Our method is simple and cost-effective. The fabricated textile has the characteristics of superhydrophobicity, magnetic responsiveness, excellent chemical stability, adjustable surface morphology, and controllable adhesion. Our findings conceivably stand out as a new tool to fabricate functional superhydrophobic materials with asymmetric surface properties for various potential applications.

  2. Aptamer-Based Dual-Functional Probe for Rapid and Specific Counting and Imaging of MCF-7 Cells.

    PubMed

    Yang, Bin; Chen, Beibei; He, Man; Yin, Xiao; Xu, Chi; Hu, Bin

    2018-02-06

    Development of multimodal detection technologies for accurate diagnosis of cancer at early stages is in great demand. In this work, we report a novel approach using an aptamer-based dual-functional probe for rapid, sensitive, and specific counting and visualization of MCF-7 cells by inductively coupled plasma-mass spectrometry (ICP-MS) and fluorescence imaging. The probe consists of a recognition unit of aptamer to catch cancer cells specifically, a fluorescent dye (FAM) moiety for fluorescence resonance energy transfer (FRET)-based "off-on" fluorescence imaging as well as gold nanoparticles (Au NPs) tag for both ICP-MS quantification and fluorescence quenching. Due to the signal amplification effect and low spectral interference of Au NPs in ICP-MS, an excellent linearity and sensitivity were achieved. Accordingly, a limit of detection of 81 MCF-7 cells and a relative standard deviation of 5.6% (800 cells, n = 7) were obtained. The dynamic linear range was 2 × 10 2 to 1.2 × 10 4 cells, and the recoveries in human whole blood were in the range of 98-110%. Overall, the established method provides quantitative and visualized information on MCF-7 cells with a simple and rapid process and paves the way for a promising strategy for biomedical research and clinical diagnostics.

  3. Isolation and characterization of a dual function protein from Allium sativum bulbs which exhibits proteolytic and hemagglutinating activities.

    PubMed

    Parisi, Mónica G; Moreno, Silvia; Fernández, Graciela

    2008-04-01

    A dual function protein was isolated from Allium sativum bulbs and was characterized. The protein had a molecular mass of 25-26 kDa under non-reducing conditions, whereas two polypeptide chains of 12.5+/-0.5 kDa were observed under reducing conditions. E-64 and leupeptin inhibited the proteolytic activity of the protein, which exhibited characteristics similar to cysteine peptidase. The enzyme exhibited substrate specificity and hydrolyzed natural substrates such as alpha-casein (K(m): 23.0 microM), azocasein, haemoglobin and gelatin. It also showed a high affinity for synthetic peptides such as Cbz-Ala-Arg-Arg-OMe-beta-Nam (K(m): 55.24 microM, k(cat): 0.92 s(-1)). The cysteine peptidase activity showed a remarkable stability after incubation at moderate temperatures (40-50 degrees C) over a pH range of 5.5-6.5. The N-terminus of the protein displayed a 100% sequence similarity to the sequences of a mannose-binding lectin isolated from garlic bulbs. Moreover, the purified protein was retained in the chromatographic column when Con-A Sepharose affinity chromatography was performed and the protein was able to agglutinate trypsin-treated rabbit red cells. Therefore, our results indicate the presence of an additional cysteine peptidase activity on a lectin previously described.

  4. Dual Functions of Lip6 and Its Regulation of Lipid Metabolism in the Oleaginous Fungus Mucor circinelloides.

    PubMed

    Zan, Xinyi; Tang, Xin; Chu, Linfang; Song, Yuanda

    2018-03-21

    Although multiple roles of lipases have been reported in yeasts and microalgae, the functions of lipases have not been studied in oleaginous filamentous fungi. Lipase Lip6 has been reported in the oleaginous filamentous fungus Mucor circinelloides with the consensus lipase motif GXSXG and the typical acyltransferase motif of H-(X) 4 -D. To demonstrate that Lip6 might play dual roles as a lipase and an acyltransferase, we performed site-directed mutagenesis in the lipase motif and the acyltransferase motif of Lip6. Mutation in the lipase motif increased cell biomass by 12%-18% and promoted lipid accumulation by 9%-24%, while mutation in the acyltransferase motif induced lipid degradation. In vitro, purified Lip6 had a slight lipase activity but had a stronger phospholipid:DAG acyltransferase activity. Enzyme activity assays in vivo and phospholipid synthesis pathway analysis suggested that phosphatidyl serine and phosphatidyl ethanolamine can be the supplier of a fatty acyl moiety to form TAG in M. circinelloides.

  5. Graphene oxide as a dual-function conductive binder for PEEK-derived microporous carbons in high performance supercapacitors

    NASA Astrophysics Data System (ADS)

    Kim, Christine H. J.; Zhang, Hongbo; Liu, Jie

    2015-06-01

    Microporous carbons (MPCs) are promising electrode materials for supercapacitors because of their high surface area and accessible pores. However, their low electrical conductivity and mechanical instability result in limited power density and poor cycle life. This work proposes a unique two-layered film made of polyetheretherketone-derived MPCs and reduced graphene oxide (rGO) as an electrode for supercapacitors. Electrochemical characterizations of films show that such a layered structure is more effective in increasing the accessibility of ions to the hydrophilic MPCs and establishing conductive paths through the rGO network than a simple mixed composite film. The two-layered structure increases the capacitance by ˜124% (237 F g-1) with excellent cycling stability (˜93% after 6000 cycles). More importantly, we demonstrate that such performance improvements result from an optimal balance between electrical conductivity and ion accessibility, which maximizes the synergistic effects of MPC and rGO. The MPCs, which are exposed to the surface, provide a highly accessible surface area for ion adsorption. The rGO serves a dual function as a conductive filler to increase the electrical conductivity and as a binder to interconnect individual MPC particles into a robust and flexible film. These findings provide a rational basis for the design of MPC-based electrodes in high performance supercapacitors.

  6. Enhanced Functional Genomic Screening Identifies Novel Mediators of Dual Leucine Zipper Kinase-Dependent Injury Signaling in Neurons.

    PubMed

    Welsbie, Derek S; Mitchell, Katherine L; Jaskula-Ranga, Vinod; Sluch, Valentin M; Yang, Zhiyong; Kim, Jessica; Buehler, Eugen; Patel, Amit; Martin, Scott E; Zhang, Ping-Wu; Ge, Yan; Duan, Yukan; Fuller, John; Kim, Byung-Jin; Hamed, Eman; Chamling, Xitiz; Lei, Lei; Fraser, Iain D C; Ronai, Ze'ev A; Berlinicke, Cynthia A; Zack, Donald J

    2017-06-21

    Dual leucine zipper kinase (DLK) has been implicated in cell death signaling secondary to axonal damage in retinal ganglion cells (RGCs) and other neurons. To better understand the pathway through which DLK acts, we developed enhanced functional genomic screens in primary RGCs, including use of arrayed, whole-genome, small interfering RNA libraries. Explaining why DLK inhibition is only partially protective, we identify leucine zipper kinase (LZK) as cooperating with DLK to activate downstream signaling and cell death in RGCs, including in a mouse model of optic nerve injury, and show that the same pathway is active in human stem cell-derived RGCs. Moreover, we identify four transcription factors, JUN, activating transcription factor 2 (ATF2), myocyte-specific enhancer factor 2A (MEF2A), and SRY-Box 11 (SOX11), as being the major downstream mediators through which DLK/LZK activation leads to RGC cell death. Increased understanding of the DLK pathway has implications for understanding and treating neurodegenerative diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. The Type VI Secretion System Engages a Redox-Regulated Dual-Functional Heme Transporter for Zinc Acquisition.

    PubMed

    Si, Meiru; Wang, Yao; Zhang, Bing; Zhao, Chao; Kang, Yiwen; Bai, Haonan; Wei, Dawei; Zhu, Lingfang; Zhang, Lei; Dong, Tao G; Shen, Xihui

    2017-07-25

    The type VI secretion system was recently reported to be involved in zinc acquisition, but the underlying mechanism remains unclear. Here, we report that Burkholderia thailandensis T6SS4 is involved in zinc acquisition via secretion of a zinc-scavenging protein, TseZ, that interacts with the outer membrane heme transporter HmuR. We find that HmuR is a redox-regulated dual-functional transporter that transports heme iron under normal conditions but zinc upon sensing extracellular oxidative stress, triggered by formation of an intramolecular disulfide bond. Acting as the first line of defense against oxidative stress, HmuR not only guarantees an immediate response to the changing environment but also provides a fine-tuned mechanism that allows a gradual response to perceived stress. The T6SS/HmuR-mediated active zinc transport system is also involved in bacterial virulence and contact-independent bacterial competition. We describe a sophisticated bacterial zinc acquisition mechanism affording insights into the role of metal ion transport systems. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  8. Highly mesoporous single-crystalline zeolite beta synthesized using a nonsurfactant cationic polymer as a dual-function template.

    PubMed

    Zhu, Jie; Zhu, Yihan; Zhu, Liangkui; Rigutto, Marcello; van der Made, Alexander; Yang, Chengguang; Pan, Shuxiang; Wang, Liang; Zhu, Longfeng; Jin, Yinying; Sun, Qi; Wu, Qinming; Meng, Xiangju; Zhang, Daliang; Han, Yu; Li, Jixue; Chu, Yueying; Zheng, Anmin; Qiu, Shilun; Zheng, Xiaoming; Xiao, Feng-Shou

    2014-02-12

    Mesoporous zeolites are useful solid catalysts for conversion of bulky molecules because they offer fast mass transfer along with size and shape selectivity. We report here the successful synthesis of mesoporous aluminosilicate zeolite Beta from a commercial cationic polymer that acts as a dual-function template to generate zeolitic micropores and mesopores simultaneously. This is the first demonstration of a single nonsurfactant polymer acting as such a template. Using high-resolution electron microscopy and tomography, we discovered that the resulting material (Beta-MS) has abundant and highly interconnected mesopores. More importantly, we demonstrated using a three-dimensional electron diffraction technique that each Beta-MS particle is a single crystal, whereas most previously reported mesoporous zeolites are comprised of nanosized zeolitic grains with random orientations. The use of nonsurfactant templates is essential to gaining single-crystalline mesoporous zeolites. The single-crystalline nature endows Beta-MS with better hydrothermal stability compared with surfactant-derived mesoporous zeolite Beta. Beta-MS also exhibited remarkably higher catalytic activity than did conventional zeolite Beta in acid-catalyzed reactions involving large molecules.

  9. Light curing through glass ceramics: effect of curing mode on micromechanical properties of dual-curing resin cements.

    PubMed

    Flury, Simon; Lussi, Adrian; Hickel, Reinhard; Ilie, Nicoleta

    2014-04-01

    The aim of this study was to investigate micromechanical properties of five dual-curing resin cements after different curing modes including light curing through glass ceramic materials. Vickers hardness (VH) and indentation modulus (Y HU) of Panavia F2.0, RelyX Unicem 2 Automix, SpeedCEM, BisCem, and BeautiCem SA were measured after 1 week of storage (37 °C, 100 % humidity). The resin cements were tested following self-curing or light curing with the second-generation light-emitting diode (LED) curing unit Elipar FreeLight 2 in Standard Mode (1,545 mW/cm(2)) or with the third-generation LED curing unit VALO in High Power Mode (1,869 mW/cm(2)) or in XtraPower Mode (3,505 mW/cm(2)). Light curing was performed directly or through glass ceramic discs of 1.5 or 3 mm thickness of IPS Empress CAD or IPS e.max CAD. VH and Y HU were analysed with Kruskal-Wallis tests followed by pairwise Wilcoxon rank sum tests (α = 0.05). RelyX Unicem 2 Automix resulted in the highest VH and Y HU followed by BeautiCem SA, BisCem, SpeedCEM, and finally Panavia F2.0. Self-curing of RelyX Unicem 2 Automix and SpeedCEM lowered VH and Y HU compared to light curing whereas self-curing of Panavia F2.0, BisCem, and BeautiCem SA led to similar or significantly higher VH and Y HU compared to light curing. Generally, direct light curing resulted in similar or lower VH and Y HU compared to light curing through 1.5-mm-thick ceramic discs. Light curing through 3-mm-thick discs of IPS e.max CAD generally reduced VH and Y HU for all resin cements except SpeedCEM, which was the least affected by light curing through ceramic discs. The resin cements responded heterogeneously to changes in curing mode. The applied irradiances and light curing times adequately cured the resin cements even through 1.5-mm-thick ceramic discs. When light curing resin cements through thick glass ceramic restorations, clinicians should consider to prolong the light curing times even with LED curing units providing high

  10. Sulfonic Groups Originated Dual-Functional Interlayer for High Performance Lithium-Sulfur Battery.

    PubMed

    Lu, Yang; Gu, Sui; Guo, Jing; Rui, Kun; Chen, Chunhua; Zhang, Sanpei; Jin, Jun; Yang, Jianhua; Wen, Zhaoyin

    2017-05-03

    The lithium-sulfur battery is one of the most prospective chemistries in secondary energy storage field due to its high energy density and high theoretical capacity. However, the dissolution of polysulfides in liquid electrolytes causes the shuttle effect, and the rapid decay of lithium sulfur battery has greatly hindered its practical application. Herein, combination of sulfonated reduced graphene oxide (SRGO) interlayer on the separator is adopted to suppress the shuttle effect. We speculate that this SRGO layer plays two roles: physically blocking the migration of polysulfide as ion selective layer and anchoring lithium polysulfide by the electronegative sulfonic group. Lewis acid-base theory and density functional theory (DFT) calculations indicate that sulfonic groups have a strong tendency to interact with lithium ions in the lithium polysulfide. Hence, the synergic effect involved by the sulfonic group contributes to the enhancement of the battery performance. Furthermore, the uniformly distributed sulfonic groups working as active sites which could induce the uniform distribution of sulfur, alleviating the excessive growth of sulfur and enhancing the utilization of active sulfur. With this interlayer, the prototype battery exhibits a high reversible discharge capacity of more than 1300 mAh g -1 and good capacity retention of 802 mAh g -1 after 250 cycles at 0.5 C rate. After 60 cycles at different rates from 0.2 to 4 C, the cell with this functional separator still recovered a high specific capacity of 1100 mAh g -1 at 0.2 C. The results demonstrate a promising interlayer design toward high performance lithium-sulfur battery with longer cycling life, high specific capacity, and rate capability.

  11. Dual-functioning peptides discovered by phage display increase the magnitude and specificity of BMSC attachment to mineralized biomaterials.

    PubMed

    Ramaraju, Harsha; Miller, Sharon J; Kohn, David H

    2017-07-01

    Design of biomaterials for cell-based therapies requires presentation of specific physical and chemical cues to cells, analogous to cues provided by native extracellular matrices (ECM). We previously identified a peptide sequence with high affinity towards apatite (VTKHLNQISQSY, VTK) using phage display. The aims of this study were to identify a human MSC-specific peptide sequence through phage display, combine it with the apatite-specific sequence, and verify the specificity of the combined dual-functioning peptide to both apatite and human bone marrow stromal cells. In this study, a combinatorial phage display identified the cell binding sequence (DPIYALSWSGMA, DPI) which was combined with the mineral binding sequence to generate the dual peptide DPI-VTK. DPI-VTK demonstrated significantly greater binding affinity (1/K D ) to apatite surfaces compared to VTK, phosphorylated VTK (VTK phos ), DPI-VTK phos , RGD-VTK, and peptide-free apatite surfaces (p < 0.01), while significantly increasing hBMSC adhesion strength (τ 50 , p < 0.01). MSCs demonstrated significantly greater adhesion strength to DPI-VTK compared to other cell types, while attachment of MC3T3 pre-osteoblasts and murine fibroblasts was limited (p < 0.01). MSCs on DPI-VTK coated surfaces also demonstrated increased spreading compared to pre-osteoblasts and fibroblasts. MSCs cultured on DPI-VTK coated apatite films exhibited significantly greater proliferation compared to controls (p < 0.001). Moreover, early and late stage osteogenic differentiation markers were elevated on DPI-VTK coated apatite films compared to controls. Taken together, phage display can identify non-obvious cell and material specific peptides to increase human MSC adhesion strength to specific biomaterial surfaces and subsequently increase cell proliferation and differentiation. These new peptides expand biomaterial design methodology for cell-based regeneration of bone defects. This strategy of combining cell and material

  12. Physical and functional properties of arrowroot starch extrudates.

    PubMed

    Jyothi, A N; Sheriff, J T; Sajeev, M S

    2009-03-01

    Arrowroot starch, a commercially underexploited tuber starch but having potential digestive and medicinal properties, has been subjected to extrusion cooking using a single screw food extruder. Different levels of feed moisture (12%, 14%, and 16%) and extrusion temperatures (140, 150, 160, 170, 180, and 190 degrees C) were used for extrusion. The physical properties--bulk density, true density, porosity, and expansion ratio; functional properties such as water absorption index, water solubility index, oil absorption index, pasting, rheological, and textural properties; and in vitro enzyme digestibility of the extrudates were determined. The expansion ratio of the extrudates ranged from 3.22 to 6.09. The water absorption index (6.52 to 8.85 g gel/g dry sample), water solubility index (15.92% to 41.31%), and oil absorption index (0.50 to 1.70 g/g) were higher for the extrudates in comparison to native starch (1.81 g gel/g dry sample, 1.16% and 0.60 g/g, respectively). The rheological properties, storage modulus, and loss modulus of the gelatinized powdered extrudates were significantly lower (P < 0.05) and these behaved like solutions rather than a paste or a gel. Hardness and toughness were more for the samples extruded at higher feed moisture and lower extrusion temperature, whereas snap force and energy were higher at lower feed moisture and temperature. There was a significant decrease in the percentage digestibility of arrowroot starch (30.07% after 30 min of incubation with the enzyme) after extrusion (25.27% to 30.56%). Extrusion cooking of arrowroot starch resulted in products with very good expansion, color, and lower digestibility, which can be exploited for its potential use as a snack food.

  13. Bombyx mori silk: From mechanical properties to functionalities

    NASA Astrophysics Data System (ADS)

    Koh, Leng Duei

    Bombyx mori silkworms are the main producer of silk worldwide. It has been used as high-end textile fibers and as surgical sutures, and is being further developed for various emerging biomedical applications including drug delivery, tissue engineering, sensing, and imaging. The silk fibroin features a hierarchical architecture consisting of beta-sheet crystallites embedded in a less ordered amorphous matrix, which accounts for its unique combination of lustre appearance, soft-to-touch texture, and impressive mechanical properties. Notably, many applications of silk take advantage of its impressive mechanical properties, which by nature surpass many natural and synthetic materials. Interestingly, both the silkworm silk and spider dragline silk share similar hierarchical architecture but possess great disparity in mechanical properties. Inspired by spider dragline silk with much superior strength and toughness, there is an ever growing interest to enhance the mechanical properties of Bombyx mori silk. Here, we design a green and facile feeding method to modulate the structures of silk fibroin at the nanoscale using citric acid (CA), and achieved greatly enhanced mechanical properties. The silk obtained (i.e., CA silk) emerges to be the intrinsically toughest silkworm silk, with mechanical properties that exceed those of the previously reported natural and enhanced silkworm silk, and compare well with those of naturally produced spider silk (including those from spiders Araneus diadematus, Nephila clavipes, etc.).The underlying interactions of CA with fibroin structures are revealed by both advanced characterizations and simulations. It is found that CA interacts with fibroin, resulted in remarkably shorter crystallites, and thus giving the outstanding strength and toughness of the CA silk. The greatly enhanced mechanical properties are expected to lead to better functionalities and wider applications of the Bombyx mori silkworm silk. Silkworms usually produce white

  14. A facile approach to prepare a dual functionalized DNA based material in a bio-deep eutectic solvent.

    PubMed

    Mondal, Dibyendu; Bhatt, Jitkumar; Sharma, Mukesh; Chatterjee, Shruti; Prasad, Kamalesh

    2014-04-18

    DNA (Salmon testes) was functionalized by Fe3O4 nanoparticles and protonated layered dititanate sheets (H2·Ti2O5·H2O) in a mixture of choline chloride and ethylene glycol (a deep eutectic solvent) to yield a hybrid material having magnetic and antibacterial properties. Ti sheets were found to interact with the phosphate moieties, while Fe interacted with the base pair of DNA in the hybrid material.

  15. Impedimetric investigation of dual electrical properties of reduced graphene-oxide-based biosensors in the detection of dopamine.

    PubMed

    Shu-Ping Lin; Jhong-Yi Ciou; Tung-Yen Lai; Tsung-Wu Lin

    2017-07-01

    Because of the properties of high charge mobility, large detection area and chemical stability of graphene, it has been applied in many biomedical applications. Graphene oxide (GO) with abundant oxygenated functional groups is easily to form an aqueous suspension by sonication. Here, the exposed areas on the patterned-circuit silicon-based chips were first modified by (3-aminopropyl) trimethoxysilane (APTMS) for later chemically immobilized GO. After that, solution-based reduction process using hydrazine was used to gain reduced GO (RGO)-based biosensors. ESCA survey spectra showed oxygen-containing functional groups of GO decreased from 47% to 5.7%, 4.1%, 3.8%, and 3.6% under varied reduction times of 30 min, 40 min, 50 min, and 60 min, respectively. D/G intensity ratio (I D /I G ) in Raman spectra showed 1.03 after 60-min reduction process. The 60-min reduction process was further used in the electrical sensing experiments. Since different deposited layers of graphene were obtained in our experimental processes, 60-min-RGO-based biosensors have been found that those immobilized RGO possessed semiconductive property as the layers are less than 11. By contrary, when the layers were above 11, the immobilized RGO would resemble metallic material. In addition, the impedimetric analyses indicated obvious signal responses above 86 kHz and showed a concentration-dependent trend in dopamine sensing in physiological phosphate buffered saline (PBS) using 60-min-RGO-based biosensors which were feature of semiconductor.

  16. Monodisperse Dual-Functional Upconversion Nanoparticles Enabled Near-Infrared Organolead Halide Perovskite Solar Cells.

    PubMed

    He, Ming; Pang, Xinchang; Liu, Xueqin; Jiang, Beibei; He, Yanjie; Snaith, Henry; Lin, Zhiqun

    2016-03-18

    Extending the spectral absorption of organolead halide perovskite solar cells from visible into near-infrared (NIR) range renders the minimization of non-absorption loss of solar photons with improved energy alignment. Herein, we report on, for the first time, a viable strategy of capitalizing on judiciously synthesized monodisperse NaYF4 :Yb/Er upconversion nanoparticles (UCNPs) as the mesoporous electrode for CH3 NH3 PbI3 perovskite solar cells and more importantly confer perovskite solar cells to be operative under NIR light. Uniform NaYF4 :Yb/Er UCNPs are first crafted by employing rationally designed double hydrophilic star-like poly(acrylic acid)-block-poly(ethylene oxide) (PAA-b-PEO) diblock copolymer as nanoreactor, imparting the solubility of UCNPs and the tunability of film porosity during the manufacturing process. The subsequent incorporation of NaYF4 :Yb/Er UCNPs as the mesoporous electrode led to a high efficiency of 17.8 %, which was further increased to 18.1 % upon NIR irradiation. The in situ integration of upconversion materials as functional components of perovskite solar cells offers the expanded flexibility for engineering the device architecture and broadening the solar spectral use. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. A Novel Dual Expression Platform for High Throughput Functional Screening of Phage Libraries in Product like Format.

    PubMed

    Xiao, Xiaodong; Chen, Yan; Mugabe, Sheila; Gao, Changshou; Tkaczyk, Christine; Mazor, Yariv; Pavlik, Peter; Wu, Herren; Dall'Acqua, William; Chowdhury, Partha Sarathi

    2015-01-01

    High throughput screenings of single chain Fv (scFv) antibody phage display libraries are currently done as soluble scFvs produced in E.coli. Due to endotoxin contaminations from bacterial cells these preparations cannot be reliably used in mammalian cell based assays. The monovalent nature and lack of Fc in soluble scFvs prevent functional assays that are dependent on target cross linking and/or Fc functions. A convenient approach is to convert scFvs into scFv.Fc fusion proteins and express them in mammalian cell lines for screening. This approach is low throughput and is only taken after primary screening of monovalent scFvs that are expressed in bacteria. There is no platform at present that combines the benefits of both bacterial and mammalian expression system for screening phage library output. We have, therefore, developed a novel dual expression vector, called pSplice, which can be used to express scFv.Fc fusion proteins both in E.coli and mammalian cell lines. The hallmark of the vector is an engineered intron which houses the bacterial promoter and signal peptide for expression and secretion of scFv.Fc in E.coli. When the vector is transfected into a mammalian cell line, the intron is efficiently spliced out resulting in a functional operon for expression and secretion of the scFv.Fc fusion protein into the culture medium. By applying basic knowledge of mammalian introns and splisosome, we designed this vector to enable screening of phage libraries in a product like format. Like IgG, the scFv.Fc fusion protein is bi-valent for the antigen and possesses Fc effector functions. Expression in E.coli maintains the speed of the bacterial expression platform and is used to triage clones based on binding and other assays that are not sensitive to endotoxin. Triaged clones are then expressed in a mammalian cell line without the need for any additional cloning steps. Conditioned media from the mammalian cell line containing the fusion proteins are then used for

  18. Dielectric properties of soils as a function of moisture content

    NASA Technical Reports Server (NTRS)

    Cihlar, J.; Ulaby, F. T.

    1974-01-01

    Soil dielectric constant measurements are reviewed and the dependence of the dielectric constant on various soil parameters is determined. Moisture content is given special attention because of its practical significance in remote sensing and because it represents the single most influential parameter as far as soil dielectric properties are concerned. Relative complex dielectric constant curves are derived as a function of volumetric soil water content at three frequencies (1.3 GHz, 4.0 GHz, and 10.0 GHz) for each of three soil textures (sand, loam, and clay). These curves, presented in both tabular and graphical form, were chosen as representative of the reported experimental data. Calculations based on these curves showed that the power reflection coefficient and emissivity, unlike skin depth, vary only slightly as a function of frequency and soil texture.

  19. Electronic properties of graphene nanoribbons: A density functional investigation

    SciTech Connect

    Kumar, Sandeep, E-mail: skumar198712@gmail.com; Sharma, Hitesh, E-mail: dr.hitesh.phys@gmail.com

    2015-05-15

    Density functional theory calculations have been performed on graphene nano ribbons (GNRs) to investigate the electronic properties as a function of chirality, size and hydrogenation on the edges. The calculations were performed on GNRs with armchair and zigzag configurations with 28, 34, 36, 40, 50, 56, 62, 66 carbon atoms. The structural stability of AGNR and ZGNR increases with the size of nanoribbon where as hydrogenation of GNR tends to lowers their structural stability. All GNRs considered have shown semiconducting behavior with HOMO-LUMO gap decreasing with the increase in the GNR size. The hydrogenation of GNR decreases its HOMO-LUMO gapmore » significantly. The results are in agreement with the available experimental and theoretical results.« less

  20. Psychometric properties of the Nurses Work Functioning Questionnaire (NWFQ).

    PubMed

    Gärtner, Fania R; Nieuwenhuijsen, Karen; van Dijk, Frank J H; Sluiter, Judith K

    2011-01-01

    The Nurses Work Functioning Questionnaire (NWFQ) is a 50-item self-report questionnaire specifically developed for nurses and allied health professionals. Its seven subscales measure impairments in the work functioning due to common mental disorders. Aim of this study is to evaluate the psychometric properties of the NWFQ, by assessing reproducibility and construct validity. The questionnaire was administered to 314 nurses and allied health professionals with a re-test in 112 subjects. Reproducibility was assessed by the intraclass correlations coefficients (ICC) and the standard error of measurement (SEM). For construct validity, correlations were calculated with a general work functioning scale, the Endicott Work Productivity Scale (EWPS) (convergent validity) and with a physical functioning scale (divergent validity). For discriminative validity, a Mann Whitney U test was performed testing for significant differences between subjects with mental health complaints and without. All subscales showed good reliability (ICC: 0.72-0.86), except for one (ICC = 0.16). Convergent validity was good in six subscales, correlations ranged from 0.38-0.62. However, in one subscale the correlation with the EWPS was too low (0.22). Divergent validity was good in all subscales based on correlations ranged from (-0.06)-(-0.23). Discriminative validity was good in all subscales, based on significant differences between subjects with and without mental health complaints (p<0.001-p = 0.003). The NWFQ demonstrates good psychometric properties, for six of the seven subscales. Subscale "impaired decision making" needs improvement before further use.

  1. Dual Function of a Tip Fimbrillin of Actinomyces in Fimbrial Assembly and Receptor Binding▿

    PubMed Central

    Wu, Chenggang; Mishra, Arunima; Yang, Jinghua; Cisar, John O.; Das, Asis; Ton-That, Hung

    2011-01-01

    Interaction of Actinomyces oris with salivary proline-rich proteins (PRPs), which serve as fimbrial receptors, involves type 1 fimbriae. Encoded by the gene locus fimQ-fimP-srtC1, the type 1 fimbria is comprised of the fimbrial shaft FimP and the tip fimbrillin FimQ. Fimbrial polymerization requires the fimbria-specific sortase SrtC1, which catalyzes covalent linkage of fimbrial subunits. Using genetics, biochemical methods, and electron microscopy, we provide evidence that the tip fimbrillin, FimQ, is involved in fimbrial assembly and interaction with PRPs. Specifically, while deletion of fimP completely abolished the type 1 fimbrial structures, surface display of monomeric FimQ was not affected by this mutation. Surprisingly, deletion of fimQ significantly reduced surface assembly of the type 1 fimbriae. This defect was rescued by recombinant FimQ ectopically expressed from a plasmid. In agreement with the role of type 1 fimbriae in binding to PRPs, aggregation of A. oris with PRP-coated beads was abrogated in cells lacking srtC1 or fimP. This aggregation defect of the ΔfimP mutant was mainly due to significant reduction of FimQ on the bacterial surface, as the aggregation was not observed in a strain lacking fimQ. Increasing expression of FimQ in the ΔfimP mutant enhanced aggregation, while overexpression of FimP in the ΔfimQ mutant did not. Furthermore, recombinant FimQ, not FimP, bound surface-associated PRPs in a dose-dependent manner. Thus, not only does FimQ function as the major adhesin of the type 1 fimbriae, it also plays an important role in fimbrial assembly. PMID:21531799

  2. DNA binding and unwinding by Hel308 helicase requires dual functions of a winged helix domain.

    PubMed

    Northall, Sarah J; Buckley, Ryan; Jones, Nathan; Penedo, J Carlos; Soultanas, Panos; Bolt, Edward L

    2017-09-01

    Hel308 helicases promote genome stability linked to DNA replication in archaea, and have homologues in metazoans. In the crystal structure of archaeal Hel308 bound to a tailed DNA duplex, core helicase domains encircle single-stranded DNA (ssDNA) in a "ratchet" for directional translocation. A winged helix domain (WHD) is also present, but its function is mysterious. We investigated the WHD in full-length Hel308, identifying that mutations in a solvent exposed α-helix resulted in reduced DNA binding and unwinding activities. When isolated from the rest of Hel308, the WHD protein alone bound to duplex DNA but not ssDNA, and DNA binding by WHD protein was abolished by the same mutations as were analyzed in full-length Hel308. Isolated WHD from a human Hel308 homologue (HelQ) also bound to duplex DNA. By disrupting the interface between the Hel308 WHD and a RecA-like domain, a topology typical of Ski2 helicases, we show that this is crucial for ATPase and helicase activities. The data suggest a model in which the WHD promotes activity of Hel308 directly, through binding to duplex DNA that is distinct from ssDNA binding by core helicase, and indirectly through interaction with the RecA-like domain. We propose how the WHD may contribute to ssDNA translocation, resulting in DNA helicase activity or in removal of other DNA bound proteins by "reeling" ssDNA. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Synthesis, molecular properties estimations, and dual dopamine D2 and D3 receptor activities of Benzthiazole-based ligands.

    NASA Astrophysics Data System (ADS)

    Schübler, Moritz; Sadek, Bassem; Kottke, Tim; Weizel, Lilia; Stark, Holger

    2017-09-01

    Neurleptic drugs, e.g. aripiprazole, targeting the dopamine D2s and D3 receptors (D2sR and D3R) in the central nervous system are widely used in the treatment of several psychotic and neurodegenerative diseases. Therefore, a new series of benz[d]thiazole-based ligands (1-18) was synthesized by applying the bioisosteric approach derived from the selective D3Rs ligand BP-897 and its structurally related benz[d]imidazole derivatives. Herein, introduction of the benz[d]thiazole moiety was well tolerated by D2sR and D3R binding sites leading to antagonist affinities in the low nanomolar concentration range at both receptor subtypes. Further exploration of different substitution patterns at the benz[d]thiazole heterocycle and the basic 4-phenylpiperazine resulted in the discovery of high dually acting D2sR and D3R ligands. Moreover, the methoxy substitution at 2-position of 4-phenylpiperazine resulted in significantly (22-fold) increased D2sR binding affinity as compared to the parent ligand BP-897, and improved physicochemical and drug-likeness properties of ligands 1-9. However, the latter structural modifications failed to improve the drug-able properties in ligands having un-substituted 4-phenylpiperazine analogues (10-18). Accordingly, compound 7 showed in addition to high dual affinity at the D2sR and D3R (Ki (hD2SR) = 2.8 ± 0.8 nM; Ki (hD3R) = 3.0 ± 1.6 nM), promising clogS, clogP, LE (hD2sR, hD3R), LipE (hD2sR, hD3R), and drug-likeness score values of -4.7, 4.2, (0.4, 0.4), (4.4, 4.3), and 0.7, respectively. Also, the deaminated analogue 8 (Ki (hD2SR) = 3.2 ± 0.4 nM; Ki (hD3R) = 8.5 ± 2.2 nM) revealed clogS, clogP, LE (hD2sR, hD3R), LipE (hD2sR, hD3R) and drug-likeness score values of -4.7, 4.2, (0.4, 0.4), (3.9, 3.5), and 0.4, respectively. The results observed for the newly developed benz[d]thiazole-based ligands 1-18 provide clues for the diversity in structure activity relationships (SARs) at the D2sR and D3R subtypes.

  4. Executive function deficits in team sport athletes with a history of concussion revealed by a visual-auditory dual task paradigm.

    PubMed

    Tapper, Anthony; Gonzalez, Dave; Roy, Eric; Niechwiej-Szwedo, Ewa

    2017-02-01

    The purpose of this study was to examine executive functions in team sport athletes with and without a history of concussion. Executive functions comprise many cognitive processes including, working memory, attention and multi-tasking. Past research has shown that concussions cause difficulties in vestibular-visual and vestibular-auditory dual-tasking, however, visual-auditory tasks have been examined rarely. Twenty-nine intercollegiate varsity ice hockey athletes (age = 19.13, SD = 1.56; 15 females) performed an experimental dual-task paradigm that required simultaneously processing visual and auditory information. A brief interview, event description and self-report questionnaires were used to assign participants to each group (concussion, no-concussion). Eighteen athletes had a history of concussion and 11 had no concussion history. The two tests involved visuospatial working memory (i.e., Corsi block test) and auditory tone discrimination. Participants completed both tasks individually, then simultaneously. Two outcome variables were measured, Corsi block memory span and auditory tone discrimination accuracy. No differences were shown when each task was performed alone; however, athletes with a history of concussion had a significantly worse performance on the tone discrimination task in the dual-task condition. In conclusion, long-term deficits in executive functions were associated with a prior history of concussion when cognitive resources were stressed. Evaluations of executive functions and divided attention appear to be helpful in discriminating participants with and without a history concussion.

  5. Effect of land use change on soil properties and functions

    NASA Astrophysics Data System (ADS)

    Tonutare, Tonu; Kõlli, Raimo; Köster, Tiina; Rannik, Kaire; Szajdak, Lech; Shanskiy, Merrit

    2014-05-01

    For good base of sustainable land management and ecologically sound protection of soils are researches on soil properties and functioning. Ecosystem approach to soil properties and functioning is equally important in both natural and cultivated land use conditions. Comparative analysis of natural and agro-ecosystems formed on similar soil types enables to elucidate principal changes caused by land use change (LUC) and to elaborate the best land use practices for local pedo-ecological conditions. Taken for actual analysis mineral soils' catena - rendzina → brown soils → pseudopodzolic soils → gley-podzols - represent ca 1/3 of total area of Estonian normal mineral soils. All soils of this catena differ substantially each from other by calcareousness, acidity, nutrition conditions, fabric and humus cover type. This catena (representative to Estonian pedo-ecological conditions) starts with drought-prone calcareous soils. Brown (distributed in northern and central Estonia) and pseudopodzolic soils (in southern Estonia) are the most broadly acknowledged for agricultural use medium-textured high-quality automorphic soils. Dispersedly distributed gley-podzols are permanently wet and strongly acid, low-productivity sandy soils. In presentation four complex functions of soils are treated: (1) being a suitable soil environment for plant cover productivity (expressed by annual increment, Mg ha-1 yr-1); (2) forming adequate conditions for decomposition, transformation and conversion of fresh falling litter (characterized by humus cover type); (3) deposition of humus, individual organic compounds, plant nutrition elements, air and water, and (4) forming (bio)chemically variegated active space for soil type specific edaphon. Capacity of soil cover as depositor (3) depends on it thickness, texture, calcareousness and moisture conditions. Biological activity of soil (4) is determined by fresh organic matter influx, quality and quantity of biochemical substances and humus

  6. The Health and Functioning ICF-60: Development and Psychometric Properties

    PubMed Central

    Tutelyan, V A; Chatterji, S; Baturin, A K; Pogozheva, A V; Kishko, O N; Akolzina, S E

    2014-01-01

    Background This paper describes the development and psychometric properties of the Health and Functioning ICF-60 (HF-ICF-60) measure, based on the World Health Organization (WHO) ‘International Classification of Functioning, Disability and Health: ICF’ (2001). The aims of the present study were to test psychometric properties of the HF-ICF-60, developed as a measure that would be responsive to change in functioning through changes in health and nutritional status, as a prospective measure to monitor health and nutritional status of populations and to explore the relationship of the HF-ICF-60 with quality of life measures such as the World Health Organization WHOQOL-BREF quality of life assessment in relation to non-communicable diseases. Methods The HF-ICF-60 measure consists of 60 items selected from the ICF by an expert panel, which included 18 items that cover Body Functions, 21 items that cover Activities and Participation, rated on five-point scales, and 21 items that cover Environmental Factors (seven items cover Individual Environmental Factors and 14 items cover Societal Environmental Factors), rated on nine-point scales. The HF-ICF-60 measure was administered to the Russian nationally representative sample within the Russian National Population Quality of Life, Health and Nutrition Survey, in 2004 (n = 9807) and 2005 (n = 9560), as part of the two waves of the Russian Longitudinal Monitoring Survey (RLMS). The statistical analyses were carried out with the use of both classical and modern psychometric methods, such as factor analysis, and based on Item Response Theory, respectively. Results The HF-ICF-60 questionnaire is a new measure derived directly from the ICF and covers the ICF components as follows: Body Functions, Activities and Participation, and Environmental Factors (Individual Environmental Factors and Societal Environmental Factors). The results from the factor analyses (both Exploratory Factor Analyses and Confirmatory Factor

  7. Mapping specific soil functions based on digital soil property maps

    NASA Astrophysics Data System (ADS)

    Pásztor, László; Fodor, Nándor; Farkas-Iványi, Kinga; Szabó, József; Bakacsi, Zsófia; Koós, Sándor

    2016-04-01

    Quantification of soil functions and services is a great challenge in itself even if the spatial relevance is supposed to be identified and regionalized. Proxies and indicators are widely used in ecosystem service mapping. Soil services could also be approximated by elementary soil features. One solution is the association of soil types with services as basic principle. Soil property maps however provide quantified spatial information, which could be utilized more versatilely for the spatial inference of soil functions and services. In the frame of the activities referred as "Digital, Optimized, Soil Related Maps and Information in Hungary" (DOSoReMI.hu) numerous soil property maps have been compiled so far with proper DSM techniques partly according to GSM.net specifications, partly by slightly or more strictly changing some of its predefined parameters (depth intervals, pixel size, property etc.). The elaborated maps have been further utilized, since even DOSoReMI.hu was intended to take steps toward the regionalization of higher level soil information (secondary properties, functions, services). In the meantime the recently started AGRAGIS project requested spatial soil related information in order to estimate agri-environmental related impacts of climate change and support the associated vulnerability assessment. One of the most vulnerable services of soils in the context of climate change is their provisioning service. In our work it was approximated by productivity, which was estimated by a sequential scenario based crop modelling. It took into consideration long term (50 years) time series of both measured and predicted climatic parameters as well as accounted for the potential differences in agricultural practice and crop production. The flexible parametrization and multiple results of modelling was then applied for the spatial assessment of sensitivity, vulnerability, exposure and adaptive capacity of soils in the context of the forecasted changes in

  8. Mung bean proteins and peptides: nutritional, functional and bioactive properties

    PubMed Central

    Yi-Shen, Zhu; Shuai, Sun; FitzGerald, Richard

    2018-01-01

    To date, no extensive literature review exists regarding potential uses of mung bean proteins and peptides. As mung bean has long been widely used as a food source, early studies evaluated mung bean nutritional value against the Food and Agriculture Organization of the United Nations (FAO)/the World Health Organization (WHO) amino acids dietary recommendations. The comparison demonstrated mung bean to be a good protein source, except for deficiencies in sulphur-containing amino acids, methionine and cysteine. Methionine and cysteine residues have been introduced into the 8S globulin through protein engineering technology. Subsequently, purified mung bean proteins and peptides have facilitated the study of their structural and functional properties. Two main types of extraction methods have been reported for isolation of proteins and peptides from mung bean flours, permitting sequencing of major proteins present in mung bean, including albumins and globulins (notably 8S globulin). However, the sequence for albumin deposited in the UniProt database differs from other sequences reported in the literature. Meanwhile, a limited number of reports have revealed other useful bioactivities for proteins and hydrolysed peptides, including angiotensin-converting enzyme inhibitory activity, anti-fungal activity and trypsin inhibitory activity. Consequently, several mung bean hydrolysed peptides have served as effective food additives to prevent proteolysis during storage. Ultimately, further research will reveal other nutritional, functional and bioactive properties of mung bean for uses in diverse applications. PMID:29545737

  9. Functional and rheological properties of cold plasma treated rice starch.

    PubMed

    Thirumdas, Rohit; Trimukhe, A; Deshmukh, R R; Annapure, U S

    2017-02-10

    The present work deals with aimed to study the effect of cold plasma treatment on the functional and rheological properties of rice starch using two different power levels (40 and 60W). The changes in amylose content, turbidity, pH, water and fat absorption due to plasma treatment were evaluated. Where decrease in the turbidity and pH after the treatment was observed. Gel hydration properties and syneresis study revealed that there is an increase in leaching of amylose molecules after the treatment. Rapid Visco Analyzer examination showed an increase in pasting and final viscosities. From G' and G″ moduli determination we observed that there is decrease in retrogradation tendency of starch gels. XRD did not show any change in A-type pattern but decrease in the relative crystallinity was observed due to depolymerization caused by active plasma species. FTIR shows some of the additional functional groups after treatment. SEM showed formation of fissures on the surface of starch granules due to etching caused by the plasma species. Thus, plasma treatment can be one of the methods for physical modification of starch. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Maintaining functional properties of shell eggs by ultrasound treatment.

    PubMed

    Caner, Cengiz; Yuceer, Muhammed

    2015-11-01

    Ultrasonic treatment is an emerging technique that could be an alternative to existing thermal processing techniques in foods. Ultrasonic treatments may also be used to extend the shelf life of egg during storage period in ambient temperature. The effectiveness of ultrasound treatment with different power levels (200 W, 300 W, 450 W) and treatment times (2 min and 5 min) was evaluated for enhancing the functional properties of eggs during storage at 24 ° C for 6 weeks. Ultrasound treatment power and treatment time had significant effects on Haugh unit, yolk index, albumen pH, dry matter, relative whipping capacity, and albumen viscosity resulting in extended shelf life. Attributes such as yolk index, Haugh unit, pH, whipping capacity, dry matter for 300 W and 450 W treatments were better than control and 200 W treatments. Longer treatment time and power showed a significant influence on functional properties. Power levels of 300 W and 450 W of ultrasound treatments had improved internal quality of fresh eggs during storage, but negative effect on shell strength. The study showed that ultrasound treatment could be an alternative and effective technique for maintaining the internal qualities of fresh eggs during long-term storage while Fourier transform near infrared spectroscopy could be used as a new tool for the assessment of freshness. © 2014 Society of Chemical Industry.

  11. Functional properties of tropical banded cricket (Gryllodes sigillatus) protein hydrolysates.

    PubMed

    Hall, Felicia G; Jones, Owen G; O'Haire, Marguerite E; Liceaga, Andrea M

    2017-06-01

    Recently, the benefits of entomophagy have been widely discussed. Due to western cultures' reluctance, entomophagy practices are leaning more towards incorporating insects into food products. In this study, whole crickets (Gryllodes sigillatus) were hydrolyzed with alcalase at 0.5, 1.5, and 3.0% (w/w) for 30, 60, and 90min. Degree of hydrolysis (DH), amino acid composition, solubility, emulsion and foaming properties were evaluated. Hydrolysis produced peptides with 26-52% DH compared to the control containing no enzyme (5% DH). Protein solubility of hydrolysates improved (p<0.05) over a range of pH's, exhibiting >30% soluble protein at pH 3 and 7 and 50-90% at alkaline pH, compared with the control. Emulsion activity index ranged from 7 to 32m 2 /g, while foamability ranged from 100 to 155% for all hydrolysates. These improved functional properties demonstrate the potential to develop cricket protein hydrolysates as a source of functional alternative protein in food ingredient formulations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Yeasts from autochthonal cheese starters: technological and functional properties.

    PubMed

    Binetti, A; Carrasco, M; Reinheimer, J; Suárez, V

    2013-08-01

    The aim of this work was to identify 20 yeasts isolated from autochthonal cheese starters and evaluate their technological and functional properties. The capacities of the yeasts to grow at different temperatures, pH, NaCl and lactic acid concentrations as well as the proteolytic and lipolytic activities were studied. Moreover, survival to simulated gastrointestinal digestion, hydrophobicity, antimicrobial activity against pathogens and auto- and co-aggregation abilities were evaluated. The sequentiation of a fragment from the 26S rDNA gene indicated that Kluyveromyces marxianus was the predominant species, followed by Saccharomyces cerevisiae, Clavispora lusitaniae, Kluyveromyces lactis and Galactomyces geotrichum. RAPD with primer M13 allowed a good differentiation among strains from the same species. All strains normally grew at pH 4.7-5.5 and temperatures between 15 and 35°C. Most of them tolerated 10% NaCl and 3% lactic acid. Some strains showed proteolytic (eight isolates) and/or lipolytic (four isolates) capacities. All strains evidenced high gastrointestinal resistance, moderate hydrophobicity, intermediate auto-aggregation and variable co-aggregation abilities. No strains inhibited the growth of the pathogens assayed. Some strains from dairy sources showed interesting functional and technological properties. This study has been the first contribution to the identification and characterization of yeasts isolated from autochthonal cheese starters in Argentina. Many strains could be proposed as potential candidates to be used as probiotics and/or as co-starters in cheese productions. © 2013 The Society for Applied Microbiology.

  13. Mung bean proteins and peptides: nutritional, functional and bioactive properties.

    PubMed

    Yi-Shen, Zhu; Shuai, Sun; FitzGerald, Richard

    2018-01-01

    To date, no extensive literature review exists regarding potential uses of mung bean proteins and peptides. As mung bean has long been widely used as a food source, early studies evaluated mung bean nutritional value against the Food and Agriculture Organization of the United Nations (FAO)/the World Health Organization (WHO) amino acids dietary recommendations. The comparison demonstrated mung bean to be a good protein source, except for deficiencies in sulphur-containing amino acids, methionine and cysteine. Methionine and cysteine residues have been introduced into the 8S globulin through protein engineering technology. Subsequently, purified mung bean proteins and peptides have facilitated the study of their structural and functional properties. Two main types of extraction methods have been reported for isolation of proteins and peptides from mung bean flours, permitting sequencing of major proteins present in mung bean, including albumins and globulins (notably 8S globulin). However, the sequence for albumin deposited in the UniProt database differs from other sequences reported in the literature. Meanwhile, a limited number of reports have revealed other useful bioactivities for proteins and hydrolysed peptides, including angiotensin-converting enzyme inhibitory activity, anti-fungal activity and trypsin inhibitory activity. Consequently, several mung bean hydrolysed peptides have served as effective food additives to prevent proteolysis during storage. Ultimately, further research will reveal other nutritional, functional and bioactive properties of mung bean for uses in diverse applications.

  14. Functional properties of honey, propolis, and royal jelly.

    PubMed

    Viuda-Martos, M; Ruiz-Navajas, Y; Fernández-López, J; Pérez-Alvarez, J A

    2008-11-01

    Honey, propolis, and royal jelly, products originating in the beehive, are attractive ingredients for healthy foods. Honey has been used since ancient times as part of traditional medicine. Several aspects of this use indicate that it also has functions such as antibacterial, antioxidant, antitumor, anti-inflamatory, antibrowning, and antiviral. Propolis is a resinous substance produced by honeybees. This substance has been used in folk medicine since ancient times, due to its many biological properties to possess, such as antitumor, antioxidant, antimicrobial, anti-inflammatory, and immunomodulatory effects, among others. Royal jelly has been demonstrated to possess numerous functional properties such as antibacterial activity, anti-inflammatory activity, vasodilative and hypotensive activities, disinfectant action, antioxidant activity, antihypercholesterolemic activity, and antitumor activity. Biological activities of honey, propolis, and royal jelly are mainly attributed to the phenolic compounds such as flavonoids. Flavonoids have been reported to exhibit a wide range of biological activities, including antibacterial, antiviral, anti-inflammatory, antiallergic, and vasodilatory actions. In addition, flavonoids inhibit lipid peroxidation, platelet aggregation, capillary permeability and fragility, and the activity of enzyme systems including cyclo-oxygenase and lipoxygenase.

  15. Yeast diversity of sourdoughs and associated metabolic properties and functionalities.

    PubMed

    De Vuyst, Luc; Harth, Henning; Van Kerrebroeck, Simon; Leroy, Frédéric

    2016-12-19

    Together with acidifying lactic acid bacteria, yeasts play a key role in the production process of sourdough, where they are either naturally present or added as a starter culture. Worldwide, a diversity of yeast species is encountered, with Saccharomyces cerevisiae, Candida humilis, Kazachstania exigua, Pichia kudriavzevii, Wickerhamomyces anomalus, and Torulaspora delbrueckii among the most common ones. Sourdough-adapted yeasts are able to withstand the stress conditions encountered during their growth, including nutrient starvation as well as the effects of acidic, oxidative, thermal, and osmotic stresses. From a technological point of view, their metabolism primarily contributes to the leavening and flavour of sourdough products. Besides ethanol and carbon dioxide, yeasts can produce metabolites that specifically affect flavour, such as organic acids, diacetyl, higher alcohols from branched-chain amino acids, and esters derived thereof. Additionally, several yeast strains possess functional properties that can potentially lead to nutritional and safety advantages. These properties encompass the production of vitamins, an improvement of the bioavailability of phenolic compounds, the dephosphorylation of phytic acid, the presence of probiotic potential, and the inhibition of fungi and their mycotoxin production. Strains of diverse species are new candidate functional starter cultures, offering opportunities beyond the conventional use of baker's yeast. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. A New Approach to Evaluating the Risk–Benefit Equation for Dual-Use and Gain-of-Function Research of Concern

    PubMed Central

    Imperiale, Michael J.; Casadevall, Arturo

    2018-01-01

    In the twenty-first century, biology faces a problem that has previously vexed other disciplines such as physics, namely the prospect that its knowledge domain could be used to generate biological agents with altered properties that enhanced their weapon potential. Biological weapons bring the additional dimension that these could be self-replicating, easy to manufacture and synthesized with commonly available expertise. This resulted in increasing concern about the type of research done and communicated, despite the fact that such research often has direct societal benefits, bringing the dual-use dilemma to biology. The conundrum of dual use research of concern was crystallized by the so-called “gain-of-function” type of experiments in which avian influenza viruses were endowed with new properties in the laboratory such as increased virulence and the capacity for mammalian transmission. After more than a decade of intensive discussion and controversy involving biological experiments with dual-use potential, there is no consensus on the issue except for the need to carry out such experiments in the safest conditions possible. In this essay, we review the topic with the hindsight of several years and suggest that instead of prescribing prohibitions and experimental limitations the focus should be on the importance of scientific questions at hand. We posit that the importance of a scientific question for medical and scientific progress provides a benchmark to determine the acceptable level of risk in biological experimentation. PMID:29568736

  17. Characterisation and functional properties of watermelon (Citrullus lanatus) seed proteins.

    PubMed

    Wani, Ali Abas; Sogi, Dalbir Singh; Singh, Preeti; Wani, Idrees Ahmed; Shivhare, Uma S

    2011-01-15

    People in developing countries depend largely on non-conventional protein sources to augment the availability of proteins in their diets. Watermelon seed meal is reported to contain an adequate amount of nutritional proteins that could be extracted for use as nutritional ingredients in food products. Osborne classification showed that globulin was the major protein (≥500 g kg (-1)) present in watermelon seed meal, followed by albumin and glutelin. Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated that the polypeptides had low molecular weights ranging from 35 to 47 kDa. Isoelectric focusing revealed that the isoelectric point of most proteins was in the acidic range 4-6. These proteins are rich in aspartic acid, glutamic acid and serine. An increase in pH (5-9) significantly (P < 0.05) decreased the denaturation enthalpy of these proteins. Among functional properties, albumin exhibited a much higher dispersibility index (810.3-869.6 g kg(-1)) than globulin (227.8-245.4 g kg(-1)), glutelin (182.1-187.7 g kg(-1)) and prolamin (162.3-177.7 g kg(-1)). Digestibility was in the ranges 760.6-910.0 and 765.5-888.5 g kg(-1) for Mateera and Sugar Baby watermelon protein fractions respectively, while surface hydrophobicity ranged from 126.4 to 173.2 and from 125.8 to 169.3 respectively. The foaming and emulsifying properties of albumin were better than those of the other proteins studied. The good nutritional and functional properties of watermelon seed meal proteins suggest their potential use in food formulations. Copyright © 2010 Society of Chemical Industry.

  18. Physical characterization of functionalized spider silk: electronic and sensing properties

    PubMed Central

    Steven, Eden; Park, Jin Gyu; Paravastu, Anant; Lopes, Elsa Branco; Brooks, James S; Englander, Ongi; Siegrist, Theo; Kaner, Papatya; Alamo, Rufina G

    2011-01-01

    This work explores functional, fundamental and applied aspects of naturally harvested spider silk fibers. Natural silk is a protein polymer where different amino acids control the physical properties of fibroin bundles, producing, for example, combinations of β-sheet (crystalline) and amorphous (helical) structural regions. This complexity presents opportunities for functional modification to obtain new types of material properties. Electrical conductivity is the starting point of this investigation, where the insulating nature of neat silk under ambient conditions is described first. Modification of the conductivity by humidity, exposure to polar solvents, iodine doping, pyrolization and deposition of a thin metallic film are explored next. The conductivity increases exponentially with relative humidity and/or solvent, whereas only an incremental increase occurs after iodine doping. In contrast, iodine doping, optimal at 70 °C, has a strong effect on the morphology of silk bundles (increasing their size), on the process of pyrolization (suppressing mass loss rates) and on the resulting carbonized fiber structure (that becomes more robust against bending and strain). The effects of iodine doping and other functional parameters (vacuum and thin film coating) motivated an investigation with magic angle spinning nuclear magnetic resonance (MAS-NMR) to monitor doping-induced changes in the amino acid-protein backbone signature. MAS-NMR revealed a moderate effect of iodine on the helical and β-sheet structures, and a lesser effect of gold sputtering. The effects of iodine doping were further probed by Fourier transform infrared (FTIR) spectroscopy, revealing a partial transformation of β-sheet-to-amorphous constituency. A model is proposed, based on the findings from the MAS-NMR and FTIR, which involves iodine-induced changes in the silk fibroin bundle environment that can account for the altered physical properties. Finally, proof-of-concept applications of

  19. A fluoride-sensing receptor based on 2,2'-bis(indolyl)methane by dual-function of colorimetry and fluorescence.

    PubMed

    Wei, Wei; Shao, Shi Jun; Guo, Yong

    2015-10-05

    A compound based on 2,2'-bis(indolyl)methane containing nitro group was studied as a new anion receptor. It could recognize selectively F(-) by an increasing fluorescence signal and a visible color change from colorless to blue. The introduction of nitro group induced the spectral dual-function related to the deprotonation of N-H protons. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. 23 CFR 710.509 - Functional replacement of real property in public ownership.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Functional replacement is permitted under State law and the STD elects to provide it. (2) The property in... STD determination that functional replacement is in the public interest. (6) The real property is not...

  1. 23 CFR 710.509 - Functional replacement of real property in public ownership.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Functional replacement is permitted under State law and the STD elects to provide it. (2) The property in... STD determination that functional replacement is in the public interest. (6) The real property is not...

  2. 23 CFR 710.509 - Functional replacement of real property in public ownership.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Functional replacement is permitted under State law and the STD elects to provide it. (2) The property in... STD determination that functional replacement is in the public interest. (6) The real property is not...

  3. N-Functionalized MXenes: ultrahigh carrier mobility and multifunctional properties.

    PubMed

    Shao, Yangfan; Zhang, Fang; Shi, Xingqiang; Pan, Hui

    2017-11-01

    Two dimensional (2D) nanomaterials have demonstrated huge potential in wide applications from nanodevices to energy harvesting/storage. In this work, we propose a new class of 2D monolayers, nitrogen-functionalized MXenes (Nb 2 CN 2 and Ta 2 CN 2 ), based on density-functional theory (DFT). We find that these monolayers are direct semiconductors with near linear energy dispersions at the Γ point. M 2 CN 2 monolayers have significant small effective mass and show an ultra-high mobility of up to 10 6 cm 2 V -1 s -1 . We show that the electronic structures of the M 2 CN 2 monolayers can be easily controlled by biaxial and uniaxial strains. Importantly, the carrier mobility and direct band gap can be dramatically increased within a certain range of strain. A direct-indirect band gap transition can be triggered and the band gap can be tuned under strain. The tunable electronic properties are attributed to the structural changes and charge redistribution under stain. Our findings demonstrate that N-functionalized MXenes are promising materials for nanodevices with high speed and low power.

  4. Functionally-interdependent shape-switching nanoparticles with controllable properties

    PubMed Central

    Halman, Justin R.; Satterwhite, Emily; Roark, Brandon; Chandler, Morgan; Viard, Mathias; Ivanina, Anna; Bindewald, Eckart; Kasprzak, Wojciech K.; Panigaj, Martin; Bui, My N.; Lu, Jacob S.; Miller, Johann; Khisamutdinov, Emil F.; Shapiro, Bruce A.; Dobrovolskaia, Marina A.

    2017-01-01

    Abstract We introduce a new concept that utilizes cognate nucleic acid nanoparticles which are fully complementary and functionally-interdependent to each other. In the described approach, the physical interaction between sets of designed nanoparticles initiates a rapid isothermal shape change which triggers the activation of multiple functionalities and biological pathways including transcription, energy transfer, functional aptamers and RNA interference. The individual nanoparticles are not active and have controllable kinetics of re-association and fine-tunable chemical and thermodynamic stabilities. Computational algorithms were developed to accurately predict melting temperatures of nanoparticles of various compositions and trace the process of their re-association in silico. Additionally, tunable immunostimulatory properties of described nanoparticles suggest that the particles that do not induce pro-inflammatory cytokines and high levels of interferons can be used as scaffolds to carry therapeutic oligonucleotides, while particles with strong interferon and mild pro-inflammatory cytokine induction may qualify as vaccine adjuvants. The presented concept provides a simple, cost-effective and straightforward model for the development of combinatorial regulation of biological processes in nucleic acid nanotechnology. PMID:28108656

  5. A dual-channel fluorescent chemosensor for discriminative detection of glutathione based on functionalized carbon quantum dots.

    PubMed

    Huang, Yuanyuan; Zhou, Jin; Feng, Hui; Zheng, Jieyu; Ma, Hui-Min; Liu, Weidong; Tang, Cong; Ao, Hang; Zhao, Meizhi; Qian, Zhaosheng

    2016-12-15

    A convenient, fluorescent dual-channel chemosensor on the basis of bis(3-pyridylmethyl)amine-functionalized carbon quantum dots (BPMA-CQDs) nanoprobe was constructed, and it can discriminatively detect glutathione from its analogues cysteine and homocysteine based on two distinctive strategies. Two distinct fluorescence responses of BPMA-CQDs probe to Cu(II) and Ag(I) were identified and further employed to achieve selective detection of Cu(II) and Ag(I) respectively. Based on the BPMA-CQDs/Cu(II) conjugate, discriminative detection of GSH was achieved in terms of correlation between the amounts of GSH and fluorescence recovery. The addition of GSH into BPMA-CQDs/Cu(II) system induces the reduction of Cu(II) to Cu(I), which could efficiently block PET process resulting in the following fluorescence recovery. Based on the BPMA-CQDs/Ag(I) conjugate, GSH assay could also be established on the basis of fluorescence response to GSH. The introduction of GSH into the preceding system triggers the competitive coordination to Ag(I) between BPMA and GSH, and silver ions are finally taken away by GSH from the probe, where the fluorescence is restored to its original weak state. Both of the detection strategies can achieve discriminative detection of GSH from Cys and Hcy. The assays showed good stability and repeatability, and covered a broad linear range of up to 13.3μM with a lowest detection limit of 42.0nM. Moreover, both of them were utilized to monitor GSH level in live cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Evaluation of Functional Marrow Irradiation Based on Skeletal Marrow Composition Obtained Using Dual-Energy Computed Tomography

    SciTech Connect

    Magome, Taiki; Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota; Department of Radiology, The University of Tokyo Hospital, Tokyo

    Purpose: To develop an imaging method to characterize and map marrow composition in the entire skeletal system, and to simulate differential targeted marrow irradiation based on marrow composition. Methods and Materials: Whole-body dual energy computed tomography (DECT) images of cadavers and leukemia patients were acquired, segmented to separate bone marrow components, namely, bone, red marrow (RM), and yellow marrow (YM). DECT-derived marrow fat fraction was validated using histology of lumbar vertebrae obtained from cadavers. The fractions of RM (RMF = RM/total marrow) and YMF were calculated in each skeletal region to assess the correlation of marrow composition with sites and ages. Treatmentmore » planning was simulated to target irradiation differentially at a higher dose (18 Gy) to either RM or YM and a lower dose (12 Gy) to the rest of the skeleton. Results: A significant correlation between fat fractions obtained from DECT and cadaver histology samples was observed (r=0.861, P<.0001, Pearson). The RMF decreased in the head, neck, and chest was significantly inversely correlated with age but did not show any significant age-related changes in the abdomen and pelvis regions. Conformity of radiation to targets (RM, YM) was significantly dependent on skeletal sites. The radiation exposure was significantly reduced (P<.05, t test) to organs at risk (OARs) in RM and YM irradiation compared with standard total marrow irradiation (TMI). Conclusions: Whole-body DECT offers a new imaging technique to visualize and measure skeletal-wide marrow composition. The DECT-based treatment planning offers volumetric and site-specific precise radiation dosimetry of RM and YM, which varies with aging. Our proposed method could be used as a functional compartment of TMI for further targeted radiation to specific bone marrow environment, dose escalation, reduction of doses to OARs, or a combination of these factors.« less

  7. A dual positional specific lipoxygenase functions in the generation of flavor compounds during climacteric ripening of apple

    PubMed Central

    Schiller, Doreen; Contreras, Carolina; Vogt, Jörg; Dunemann, Frank; Defilippi, Bruno G; Beaudry, Randolph; Schwab, Wilfried

    2015-01-01

    Lipoxygenase (LOX) is an important contributor to the formation of aroma-active C6 aldehydes in apple (Malus × domestica) fruit upon tissue disruption but little is known about its role in autonomously produced aroma volatiles from intact tissue. We explored the expression of 22 putative LOX genes in apple throughout ripening, but only six LOXs were expressed in a ripening-dependent manner. Recombinant LOX1:Md:1a, LOX1:Md:1c, LOX2:Md:2a and LOX2:Md:2b proteins showed 13/9-LOX, 9-LOX, 13/9-LOX and 13-LOX activity with linoleic acid, respectively. While products of LOX1:Md:1c and LOX2:Md:2b were S-configured, LOX1:Md:1a and LOX2:Md:2a formed 13(R)-hydroperoxides as major products. Site-directed mutagenesis of Gly567 to an alanine converted the dual positional specific LOX1:Md:1a to an enzyme with a high specificity for 9(S)-hydroperoxide formation. The high expression level of the corresponding MdLOX1a gene in stored apple fruit, the genetic association with a quantitative trait locus for fruit ester and the remarkable agreement in regio- and stereoselectivity of the LOX1:Md:1a reaction with the overall LOX activity found in mature apple fruits, suggest a major physiological function of LOX1:Md:1a during climacteric ripening of apples. While LOX1:Md:1c, LOX2:Md:2a and LOX2:Md:2b may contribute to aldehyde production in immature fruit upon cell disruption our results furnish additional evidence that LOX1:Md:1a probably regulates the availability of precursors for ester production in intact fruit tissue. PMID:26504564

  8. Dual functional passivating layer of graphene/TiO2 for improved performance of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Shahid, Muhammad Umair; Mohamed, Norani Muti; Muhsan, Ali Samer; Khatani, Mehboob; Bashiri, Robabeh; Zaine, Siti Nur Azella; Shamsudin, Adel Eskandar

    2018-02-01

    The FTO/TiO2 interface plays a crucial role in the performance of dye-sensitized solar cells (DSSCs). The uneven microstructure morphology of FTO (fluorine-doped tin oxide) glass surface and high porosity of TiO2 layer produce tiny gaps and voids at the FTO/TiO2 interface that breaks the connectivity, leading to an increase in the recombination process. In the current work, a dual functional passivating layer is introduced by the combination of the graphene/TiO2 compact layer. The excellent mobility and flexibility of graphene is capitalized using its layer to fill the voids in the FTO surface, which can consequently reduce the charge transfer resistance at the interface, while the added TiO2 compact layer avoids direct contact with the electrolyte thus reducing the recombination. Graphene was synthesized by the facile solvent exfoliation method with the assistance of the probe sonication process. The parameters of sonication were optimized to achieve high-quality concentrated graphene inks (0.177-0.51 mg/ml). Raman spectroscopy and transmission electron microscopy (TEM) revealed that the graphene obtained is of a few-layer type. Electrochemical impedance spectroscopy (EIS) analysis indicated that the incorporated compact layer of graphene/TiO2 was capable of accelerating the charge transfer and reducing the recombination process at the FTO/TiO2 interface. Consequently, the photoconversion efficiency (PCE) for the device (1 cm2 active area) with double-coated graphene layer under one sun irradiation (AM 1.5) was found to be 49.49% higher than the conventional one.

  9. Dual responsive dysprosium-doped hydroxyapatite particles and toxicity reduction after functionalization with folic and glucuronic acids.

    PubMed

    Sánchez Lafarga, Ana Karen; Pacheco Moisés, Fermín P; Gurinov, Andrey; Ortiz, Genaro Gabriel; Carbajal Arízaga, Gregorio Guadalupe

    2015-03-01

    The development of probes for biomedical applications demands materials with low toxicity levels besides fluorescence or magnetic properties to be detected by confocal microscopes or MRI resonators. Several drug delivery systems or other biomedical materials prepared with hydroxyapatite have been proposed, however, toxicity effects might arise when the size of particles is nanometric. In this study, hydroxyapatite functionalized with glucuronic or folic acids presented lower oxidative stress, measured from lipoperoxides and nitric oxide indicators in rats than pure hydroxyapatite. In separated experiments, hydroxyapatite was doped with dysprosium cations by coprecipitation producing a single crystal phase with fluorescent properties easily visualized by confocal microscopy when excited at 488nm. These particles also presented the ability to modify the proton relaxation time in T1 maps collected by magnetic resonance imaging. These modified hydroxyapatite nanoparticles could be candidates to design bimodal probes with low toxicity. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. 23 CFR 710.509 - Functional replacement of real property in public ownership.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Functional replacement of real property in public... Functional replacement of real property in public ownership. (a) General. When publicly owned real property...) Federal participation. Federal-aid funds may participate in functional replacement costs only if: (1...

  11. Enhanced electrical properties of dual-layer channel ZnO thin film transistors prepared by atomic layer deposition

    NASA Astrophysics Data System (ADS)

    Li, Huijin; Han, Dedong; Dong, Junchen; Yu, Wen; Liang, Yi; Luo, Zhen; Zhang, Shengdong; Zhang, Xing; Wang, Yi

    2018-05-01

    The thin film transistors (TFTs) with a dual-layer channel structure combing ZnO thin layer grown at 200 °C and ZnO film grown at 120 °C by atomic layer deposition are fabricated. The dual-layer channel TFT exhibits a low leakage current of 2.8 × 10-13 A, Ion/Ioff ratio of 3.4 × 109, saturation mobility μsat of 12 cm2 V-1 s-1, subthreshold swing (SS) of 0.25 V/decade. The SS value decreases to 0.18 V/decade after the annealing treatment in O2 due to the reduction of the trap states at the channel/dielectric interface and in the bulk channel layer. The enhanced performance obtained from the dual-layer channel TFTs is due to the ability of maintaining high mobility and suppressing the increase in the off-current at the same time.

  12. Spectral properties from Matsubara Green's function approach: Application to molecules

    NASA Astrophysics Data System (ADS)

    Schüler, M.; Pavlyukh, Y.

    2018-03-01

    We present results for many-body perturbation theory for the one-body Green's function at finite temperatures using the Matsubara formalism. Our method relies on the accurate representation of the single-particle states in standard Gaussian basis sets, allowing to efficiently compute, among other observables, quasiparticle energies and Dyson orbitals of atoms and molecules. In particular, we challenge the second-order treatment of the Coulomb interaction by benchmarking its accuracy for a well-established test set of small molecules, which includes also systems where the usual Hartree-Fock treatment encounters difficulties. We discuss different schemes how to extract quasiparticle properties and assess their range of applicability. With an accurate solution and compact representation, our method is an ideal starting point to study electron dynamics in time-resolved experiments by the propagation of the Kadanoff-Baym equations.

  13. Diverse Functional Properties of Wilson Disease ATP7B Variants

    PubMed Central

    Huster, Dominik; Kühne, Angelika; Bhattacharjee, Ashima; Raines, Lily; Jantsch, Vanessa; Noe, Johannes; Schirrmeister, Wiebke; Sommerer, Ines; Sabri, Osama; Berr, Frieder; Mössner, Joachim; Stieger, Bruno; Caca, Karel; Lutsenko, Svetlana

    2012-01-01

    BACKGROUND & AIMS Wilson disease is a severe disorder of copper metabolism caused by mutations in ATP7B, which encodes a copper-transporting adenosine triphosphatase. The disease presents with a variable phenotype that complicates the diagnostic process and treatment. Little is known about the mechanisms that contribute to the different phenotypes of the disease. METHODS We analyzed 28 variants of ATP7B from patients with Wilson disease that affected different functional domains; the gene products were expressed using the baculovirus expression system in Sf9 cells. Protein function was analyzed by measuring catalytic activity and copper (64Cu) transport into vesicles. We studied intracellular localization of variants of ATP7B that had measurable transport activities and were tagged with green fluorescent protein in mammalian cells using confocal laser scanning microscopy. RESULTS Properties of ATP7B variants with pathogenic amino-acid substitution varied greatly even if substitutions were in the same functional domain. Some variants had complete loss of catalytic and transport activity, whereas others lost transport activity but retained phosphor-intermediate formation or had partial losses of activity. In mammalian cells, transport-competent variants differed in stability and subcellular localization. CONCLUSIONS Variants in ATP7B associated with Wilson disease disrupt the protein’s transport activity, result in its mislocalization, and reduce its stability. Single assays are insufficient to accurately predict the effects of ATP7B variants the function of its product and development of Wilson disease. These findings will contribute to our understanding of genotype–phenotype correlation and mechanisms of disease pathogenesis. PMID:22240481

  14. [Breast milk: its nutritional composition and functional properties].

    PubMed

    Tackoen, M

    2012-09-01

    Human milk is a complex biological fluid with thousands of components. The milk composition in the mammalian species is specific and adapted to the needs of the offspring. It contains macronutrients (proteins, lipids and carbohydrates), micronutrients (minerals and vitamins) and numerous biologically active substrates. Human milk not only covers the nutritional needs of the newborn but protects the baby against infection, inflammation and oxidative stress. It has immunomodulation properties and confers trophical protection to the intestinal mucosa. The newborn infant is particularly immature: innate immunity, adaptive immunity and intestinal immaturity. Human milk will offer this exogenous protective and immunomodulating source. The development of the composition of the intestinal microflora of the neonate will be impacted by pre- and probiotic components of human milk. Current scientific knowledge of human milk properties highlights interdependency of the different components, ontogeny of the intestinal function, development of the mucosal intestinal immune system, colonization by the intestinal microbiota and protection against pathogens. Quality of these interactions influences the newborn's short and long-term health status. The promotion of breastfeeding with the support of the Baby Friendly Hospital Initiative (BFHI) program and labeling has been shown to have positive impact in public health.

  15. Silk/nano-material hybrid: properties and functions

    NASA Astrophysics Data System (ADS)

    Steven, Eden; Lebedev, Victor; Laukhina, Elena; Laukhin, Vladimir; Alamo, Rufina G.; Rovira, Concepcio; Veciana, Jaume; Brooks, James S.

    2014-03-01

    Silk continues to emerge as a material of interest in electronics. In this work, the interaction between silk and conducting nano-materials are investigated. Simple fabrication methods, physical, electronic, thermal, and actuation properties are reported for spider silk / carbon nanotube (CNT-SS) and Bombyx mori / (BEDT-TTF)-based organic molecular conductor hybrids (ET-S). The CNT-SS fibers are produced via water and shear assisted method, resulting in fibers that are tough, custom-shapeable, flexible, and electrically conducting. For ET-S bilayer films, a layer transfer technique is developed to deposit linked crystallites of (BEDT-TTF)2I3 molecular conductor onto silk films, generating highly piezoresistive semi-transparent films. In both cases, the hybridization allows us to gain additional functions by harnessing the water-dependent properties of silk materials, for example, as humidity sensor and electrical current- or water-driven actuators. SEM, TEM, FT-IR, and resistance measurements under varying temperature, strain, and relative humidity reveal the synergistic interactions between the bio- and nano-materials. E.S. is supported by NSF-DMR 1005293.

  16. Multitarget drug design strategy against Alzheimer's disease: Homoisoflavonoid Mannich base derivatives serve as acetylcholinesterase and monoamine oxidase B dual inhibitors with multifunctional properties.

    PubMed

    Li, Yan; Qiang, Xiaoming; Luo, Li; Yang, Xia; Xiao, Ganyuan; Zheng, Yunxiaozhu; Cao, Zhongcheng; Sang, Zhipei; Su, Fu; Deng, Yong

    2017-01-15

    A series of homoisoflavonoid Mannich base derivatives were designed, synthesized and evaluated as multifunctional agents against Alzheimer's disease. It demonstrated that most of the derivatives were selective AChE and MAO-B dual inhibitors with good multifunctional properties. Among them, compound 10d displayed the comprehensive advantages, with excellent AChE and MAO-B inhibitory activities (IC 50 =2.49±0.08nM and 1.74±0.0581μM, respectively), good self- and Cu 2+ -induced Aβ 1-42 aggregation inhibitory potency, antioxidant activity, biometal chelating ability and high BBB permeability. These multifunctional properties make 10d as an excellent candidate for the development of efficient drugs against AD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. First passage Brownian functional properties of snowmelt dynamics

    NASA Astrophysics Data System (ADS)

    Dubey, Ashutosh; Bandyopadhyay, Malay

    2018-04-01

    In this paper, we model snow-melt dynamics in terms of a Brownian motion (BM) with purely time dependent drift and difusion and examine its first passage properties by suggesting and examining several Brownian functionals which characterize the lifetime and reactivity of such stochastic processes. We introduce several probability distribution functions (PDFs) associated with such time dependent BMs. For instance, for a BM with initial starting point x0, we derive analytical expressions for : (i) the PDF P(tf|x0) of the first passage time tf which specify the lifetime of such stochastic process, (ii) the PDF P(A|x0) of the area A till the first passage time and it provides us numerous valuable information about the total fresh water availability during melting, (iii) the PDF P(M) associated with the maximum size M of the BM process before the first passage time, and (iv) the joint PDF P(M; tm) of the maximum size M and its occurrence time tm before the first passage time. These P(M) and P(M; tm) are useful in determining the time of maximum fresh water availability and in calculating the total maximum amount of available fresh water. These PDFs are examined for the power law time dependent drift and diffusion which matches quite well with the available data of snowmelt dynamics.

  18. Dual-enhanced photothermal conversion properties of reduced graphene oxide-coated gold superparticles for light-triggered acoustic and thermal theranostics

    NASA Astrophysics Data System (ADS)

    Lin, Li-Sen; Yang, Xiangyu; Niu, Gang; Song, Jibin; Yang, Huang-Hao; Chen, Xiaoyuan

    2016-01-01

    A rational design of highly efficient photothermal agents that possess excellent light-to-heat conversion properties is a fascinating topic in nanotheranostics. Herein, we present a facile route to fabricate size-tunable reduced graphene oxide (rGO)-coated gold superparticles (rGO-GSPs) and demonstrate their dual-enhanced photothermal conversion properties for photoacoustic imaging and photothermal therapy. For the first time, graphene oxide (GO) was directly used as an emulsifying agent for the preparation of gold superparticles (GSPs) with near-infrared absorption by the emulsion method. Moreover, GO spontaneously deposited on the surface of GSPs could also act as the precursor of the rGO shell. Importantly, both the plasmonic coupling of the self-assembled gold nanoparticles and the interaction between GSPs and rGO endow rGO-GSPs with enhanced photothermal conversion properties, allowing rGO-GSPs to be used for sensitive photoacoustic detection and efficient photothermal ablation of tumours in vivo. This study provides a facile approach to prepare colloidal superparticles-graphene hybrid nanostructures and will pave the way toward the design and optimization of photothermal nanomaterials with improved properties for theranostic applications.A rational design of highly efficient photothermal agents that possess excellent light-to-heat conversion properties is a fascinating topic in nanotheranostics. Herein, we present a facile route to fabricate size-tunable reduced graphene oxide (rGO)-coated gold superparticles (rGO-GSPs) and demonstrate their dual-enhanced photothermal conversion properties for photoacoustic imaging and photothermal therapy. For the first time, graphene oxide (GO) was directly used as an emulsifying agent for the preparation of gold superparticles (GSPs) with near-infrared absorption by the emulsion method. Moreover, GO spontaneously deposited on the surface of GSPs could also act as the precursor of the rGO shell. Importantly, both the

  19. Dual functional cholinesterase and MAO inhibitors for the treatment of Alzheimer's disease: synthesis, pharmacological analysis and molecular modeling of homoisoflavonoid derivatives.

    PubMed

    Wang, Yali; Sun, Yang; Guo, Yueyan; Wang, Zechen; Huang, Ling; Li, Xingshu

    2016-01-01

    Because of the complexity of Alzheimer's disease (AD), the multi-target-directed ligand (MTDL) strategy is expected to provide superior effects for the treatment of AD, instead of the classic one-drug-one-target strategy. In this context, we focused on the design, synthesis and evaluation of homoisoflavonoid derivatives as dual acetyl cholinesterase (AChE) and monoamine oxidase (MAO-B) inhibitors. Among all the synthesized compounds, compound 10 provided a desired balance of AChE and hMAO-B inhibition activities, with IC50 value of 3.94 and 3.44 μM, respectively. Further studies revealed that compound 10 was a mixed-type inhibitor of AChE and an irreversible inhibitor of hMAO-B, which was also confirmed by molecular modeling studies. Taken together, the data indicated that 10 was a promising dual functional agent for the treatment of AD.

  20. Submicroporous/microporous and compatible/incompatible multi-functional dual-layer polymer electrolytes and their interfacial characteristics with lithium metal anode

    NASA Astrophysics Data System (ADS)

    Lee, Young-Gi; Kyhm, Kwangseuk; Choi, Nam-Soon; Ryu, Kwang Sun

    A novel multi-functional dual-layer polymer electrolyte was prepared by impregnating the interconnected pores with an ethylene carbonate (EC)/dimethyl carbonate (DMC)/lithium hexafluorophosphate (LiPF 6) solution. An incompatible layer is based on a microporous polyethylene (PE) and a compatible layer, based on a poly(vinylidenefluoride-co-hexafluoropropylene) (P(VdF-co-HFP)) is sub-microporous and compatible with an electrolyte solution. The Li electrode/the dual-layer polymer electrolyte/Li[Ni 0.15Li 0.23M n0.62]O 2 cell showed stable cycle performance under prolonged cycle number. This behavior is due to the enhanced compatibility between the matrix polymer and the liquid electrolytes within the submicroporous compatible layer, which could lead to a controlled Li + deposition on the Li anode surface by forming homegeneous electrolyte zone near the anode.

  1. Personality Inventory for DSM-5-Short Form (PID-5-SF): Reliability, Factorial Structure, and Relationship With Functional Impairment in Dual Diagnosis Patients.

    PubMed

    Díaz-Batanero, Carmen; Ramírez-López, Juan; Domínguez-Salas, Sara; Fernández-Calderón, Fermín; Lozano, Óscar M

    2017-11-01

    Section III of the Diagnostic and Statistical Manual of Mental Disorders-Fifth edition ( DSM-5) has generated a personality paradigm consisting of 25 personality facets identified in five domains. The developed assessment instrument Personality Inventory for DSM-5 (PID-5) has showed good psychometric properties, but the potential for certain improvements still remain. In this article, a sample of 282 dual diagnosis patients is used to provide evidence of the psychometric properties of the PID-5-Short Form. The mean value of Cronbach's alpha coefficients reached .73 on the facets and .84 for domains and test-retest values ranged between .57 to .83 for facets and .70 to .87 for the domains. Confirmatory factor analyses conducted showed good fit on both models tested: the five correlated factor structure and hierarchical structure of personality traits. The WHODAS 2.0 domains of understanding and communicating, and participating in society, appear to show the strongest relationship with personality facets. In general, the PID-5-Short Form shows adequate psychometric properties for use in dual diagnosis patients.

  2. Dual functional rhodium oxide nanocorals enabled sensor for both non-enzymatic glucose and solid-state pH sensing.

    PubMed

    Dong, Qiuchen; Huang, Yikun; Song, Donghui; Wu, Huixiang; Cao, Fei; Lei, Yu

    2018-07-30

    Both pH-sensitive and glucose-responsive rhodium oxide nanocorals (Rh 2 O 3 NCs) were synthesized through electrospinning followed by high-temperature calcination. The as-prepared Rh 2 O 3 NCs were systematically characterized using various advanced techniques including scanning electron microscopy, X-ray powder diffraction and Raman spectroscopy, and then employed as a dual functional nanomaterial to fabricate a dual sensor for both non-enzymatic glucose sensing and solid-state pH monitoring. The sensing performance of the Rh 2 O 3 NCs based dual sensor toward pH and glucose was evaluated using open circuit potential, cyclic voltammetry and amperometric techniques, respectively. The results show that the as-prepared Rh 2 O 3 NCs not only maintain accurate and reversible pH sensitivity of Rh 2 O 3 , but also demonstrate a good electrocatalytic activity toward glucose oxidation in alkaline medium with a sensitivity of 11.46 μA mM -1 cm -2 , a limit of detection of 3.1 μM (S/N = 3), and a reasonable selectivity against various interferents in non-enzymatic glucose detection. Its accuracy in determining glucose in human serum samples was further demonstrated. These features indicate that the as-prepared Rh 2 O 3 NCs hold great promise as a dual-functional sensing material in the development of a high-performance sensor forManjakkal both solid-state pH and non-enzymatic glucose sensing. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Functional and Radiological Outcome of Schatzker type V and VI Tibial Plateau Fracture Treatment with Dual Plates with Minimum 3 years follow-up: A Prospective Study

    PubMed Central

    Suri, Harpreet Singh; Gangrade, Kewal

    2016-01-01

    Introduction High energy intra-articular fractures involving the tibial plateau causes various problems related to management like wound dehiscence, severe comminution leading to malalignment and delayed complications like varus collapse, implant failure and arthritis of knee joint. Aim This study was done to determine functional, radiological outcome and the complications of Schatzker V and VI tibial plateau fractures treated with bipillar plating with dual plates with a regular follow-up of atleast 3 years. Materials and Methods Total 34 cases of tibial plateau fracture type V and VI treated with dual plating were studied from January 2011 to December 2013 in KIMS Hospital were followed for minimum of 3 years. The patients were operated through an anterolateral approach for lateral plate and a medial column plate was put through a minimally invasive medial approach or an open posteromedial approach. Results Total 34 patients were evaluated postoperatively thoroughly for functional outcome using The Knee Society Score and radiological outcomes by Modified Rasmussen Assessment criteria which showed 29 patients (85.29%) had excellent and 5 patients (14.71%) had good objective knee society score. 24 patients (70.59%) had excellent, 8 patients (23.53%) had good and 1patient (2.94%) were each of poor and fair functional knee society score. Eleven patients (32.35%) had excellent, 21patients (61.76%) had good and 2 patients (5.88%) had fair radiological outcome. Conclusion We conclude that open reduction and internal fixation of high-energy tibial plateau fractures with dual plates via 2 incisions gives excellent to good functional outcome with minimal soft tissue complications. Thus, a minimally invasive approach should be used which helps in preventing soft tissue problems and helps in early wound healing. Fixation done by bipillar plating is important for early mobilization of knee joint. Early mobilization leads to better range of movements and thereby better

  4. Dual-Task Processing as a Measure of Executive Function: A Comparison between Adults with Williams and Down Syndromes

    ERIC Educational Resources Information Center

    Kittler, Phyllis M.; Krinsky-McHale, Sharon J.; Devenny, Darlynne A.

    2008-01-01

    Behavioral phenotypes of individuals with Williams syndrome and individuals with Down syndrome have been contrasted in relation to short-term memory. People with Down syndrome are stronger visuospatially and those with Williams syndrome are stronger verbally. We examined short-term memory, then explored whether dual-task processing further…

  5. Differences in Student Success as a Function of Dual Credit Enrollment for Texas Community College Students: A Multiyear Investigation

    ERIC Educational Resources Information Center

    Dixon, Dorothy B.

    2017-01-01

    Purpose: The purpose of this journal-ready dissertation was to examine dual credit enrollment with respect to student demographic characteristics and to student success of Texas community college students. The first purpose was to describe the demographic characteristics with respect to gender and ethnicity/race of Texas community college students…

  6. Realization of synaptic learning and memory functions in Y2O3 based memristive device fabricated by dual ion beam sputtering

    NASA Astrophysics Data System (ADS)

    Das, Mangal; Kumar, Amitesh; Singh, Rohit; Than Htay, Myo; Mukherjee, Shaibal

    2018-02-01

    Single synaptic device with inherent learning and memory functions is demonstrated based on a forming-free amorphous Y2O3 (yttria) memristor fabricated by dual ion beam sputtering system. Synaptic functions such as nonlinear transmission characteristics, long-term plasticity, short-term plasticity and ‘learning behavior (LB)’ are achieved using a single synaptic device based on cost-effective metal-insulator-semiconductor (MIS) structure. An ‘LB’ function is demonstrated, for the first time in the literature, for a yttria based memristor, which bears a resemblance to certain memory functions of biological systems. The realization of key synaptic functions in a cost-effective MIS structure would promote much cheaper synapse for artificial neural network.

  7. Effects of Physical-Cognitive Dual Task Training on Executive Function and Gait Performance in Older Adults: A Randomized Controlled Trial

    PubMed Central

    Falbo, S.; Condello, G.; Capranica, L.; Forte, R.

    2016-01-01

    Physical and cognitive training seem to counteract age-related decline in physical and mental function. Recently, the possibility of integrating cognitive demands into physical training has attracted attention. The purpose of this study was to evaluate the effects of twelve weeks of designed physical-cognitive training on executive cognitive function and gait performance in older adults. Thirty-six healthy, active individuals aged 72.30 ± 5.84 years were assigned to two types of physical training with major focus on physical single task (ST) training (n = 16) and physical-cognitive dual task (DT) training (n = 20), respectively. They were tested before and after the intervention for executive function (inhibition, working memory) through Random Number Generation and for gait (walking with/without negotiating hurdles) under both single and dual task (ST, DT) conditions. Gait performance improved in both groups, while inhibitory performance decreased after exercise training with ST focus but tended to increase after training with physical-cognitive DT focus. Changes in inhibition performance were correlated with changes in DT walking performance with group differences as a function of motor task complexity (with/without hurdling). The study supports the effectiveness of group exercise classes for older individuals to improve gait performance, with physical-cognitive DT training selectively counteracting the age-related decline in a core executive function essential for daily living. PMID:28053985

  8. Effects of Physical-Cognitive Dual Task Training on Executive Function and Gait Performance in Older Adults: A Randomized Controlled Trial.

    PubMed

    Falbo, S; Condello, G; Capranica, L; Forte, R; Pesce, C

    2016-01-01

    Physical and cognitive training seem to counteract age-related decline in physical and mental function. Recently, the possibility of integrating cognitive demands into physical training has attracted attention. The purpose of this study was to evaluate the effects of twelve weeks of designed physical-cognitive training on executive cognitive function and gait performance in older adults. Thirty-six healthy, active individuals aged 72.30 ± 5.84 years were assigned to two types of physical training with major focus on physical single task (ST) training ( n = 16) and physical-cognitive dual task (DT) training ( n = 20), respectively. They were tested before and after the intervention for executive function (inhibition, working memory) through Random Number Generation and for gait (walking with/without negotiating hurdles) under both single and dual task (ST, DT) conditions. Gait performance improved in both groups, while inhibitory performance decreased after exercise training with ST focus but tended to increase after training with physical-cognitive DT focus. Changes in inhibition performance were correlated with changes in DT walking performance with group differences as a function of motor task complexity (with/without hurdling). The study supports the effectiveness of group exercise classes for older individuals to improve gait performance, with physical-cognitive DT training selectively counteracting the age-related decline in a core executive function essential for daily living.

  9. Quasar Spectral Energy Distributions As A Function Of Physical Property

    NASA Astrophysics Data System (ADS)

    Townsend, Shonda; Ganguly, R.; Stark, M. A.; Derseweh, J. A.; Richmond, J. M.

    2012-05-01

    Galaxy evolution models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). In turn, models of outflows have shown particular sensitivity to the shape of the spectral energy distribution (SED), depending on the UV luminosity to transfer momentum to the gas, the X-ray luminosity to regulate how efficiently that transfer can be, etc. To investigate how SED changes with physical properties, we follow up on Richards et al. (2006), who constructed SEDs with varying luminosity. Here, we construct SEDs as a function of redshift, and physical property (black hole mass, bolometric luminosity, Eddington ratio) for volume limited samples drawn from the Sloan Digital Sky Survey, with photometry supplemented from 2MASS, WISE, GALEX, ROSAT, and Chandra. To estimate black hole masses, we adopt the scaling relations from Greene & Ho (2005) based on the H-alpha emission line FWHM. This requires redshifts less than 0.4. To construct volume-limited subsamples, we begin by adopting g=19.8 as a nominal limiting magnitude over which we are guaranteed to detect z<0.4 quasars. At redshift 0.4, we are complete down to Mg=-21.8, which yields 3300 objects from Data Release 7. At z=0.1, we are complete down to Mg=-18.5. This material is based upon work supported by the National Aeronautics and Space Administration under Grant No. 09-ADP09-0016 issued through the Astrophysics Data Analysis Program.

  10. Antioxidant Properties of Kynurenines: Density Functional Theory Calculations

    PubMed Central

    2016-01-01

    Kynurenines, the main products of tryptophan catabolism, possess both prooxidant and anioxidant effects. Having multiple neuroactive properties, kynurenines are implicated in the development of neurological and cognitive disorders, such as Alzheimer's, Parkinson's, and Huntington's diseases. Autoxidation of 3-hydroxykynurenine (3HOK) and its derivatives, 3-hydroxyanthranilic acid (3HAA) and xanthommatin (XAN), leads to the hyperproduction of reactive oxygen species (ROS) which damage cell structures. At the same time, 3HOK and 3HAA have been shown to be powerful ROS scavengers. Their ability to quench free radicals is believed to result from the presence of the aromatic hydroxyl group which is able to easily abstract an electron and H-atom. In this study, the redox properties for kynurenines and several natural and synthetic antioxidants have been calculated at different levels of density functional theory in the gas phase and water solution. Hydroxyl bond dissociation enthalpy (BDE) and ionization potential (IP) for 3HOK and 3HAA appear to be lower than for xanthurenic acid (XAA), several phenolic antioxidants, and ascorbic acid. BDE and IP for the compounds with aromatic hydroxyl group are lower than for their precursors without hydroxyl group. The reaction rate for H donation to *O-atom of phenoxyl radical (Ph-O*) and methyl peroxy radical (Met-OO*) decreases in the following rankings: 3HOK ~ 3HAA > XAAOXO > XAAENOL. The enthalpy absolute value for Met-OO* addition to the aromatic ring of the antioxidant radical increases in the following rankings: 3HAA* < 3HOK* < XAAOXO* < XAAENOL*. Thus, the high free radical scavenging activity of 3HAA and 3HOK can be explained by the easiness of H-atom abstraction and transfer to O-atom of the free radical, rather than by Met-OO* addition to the kynurenine radical. PMID:27861556

  11. Identifying the molecular functions of electron transport proteins using radial basis function networks and biochemical properties.

    PubMed

    Le, Nguyen-Quoc-Khanh; Nguyen, Trinh-Trung-Duong; Ou, Yu-Yen

    2017-05-01

    The electron transport proteins have an important role in storing and transferring electrons in cellular respiration, which is the most proficient process through which cells gather energy from consumed food. According to the molecular functions, the electron transport chain components could be formed with five complexes with several different electron carriers and functions. Therefore, identifying the molecular functions in the electron transport chain is vital for helping biologists understand the electron transport chain process and energy production in cells. This work includes two phases for discriminating electron transport proteins from transport proteins and classifying categories of five complexes in electron transport proteins. In the first phase, the performances from PSSM with AAIndex feature set were successful in identifying electron transport proteins in transport proteins with achieved sensitivity of 73.2%, specificity of 94.1%, and accuracy of 91.3%, with MCC of 0.64 for independent data set. With the second phase, our method can approach a precise model for identifying of five complexes with different molecular functions in electron transport proteins. The PSSM with AAIndex properties in five complexes achieved MCC of 0.51, 0.47, 0.42, 0.74, and 1.00 for independent data set, respectively. We suggest that our study could be a power model for determining new proteins that belongs into which molecular function of electron transport proteins. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. An Evaluation of Global and Local Tensile Properties of Friction-Stir Welded DP980 Dual-Phase Steel Joints Using a Digital Image Correlation Method

    PubMed Central

    Lee, Hyoungwook; Kim, Cheolhee; Song, Jung Han

    2015-01-01

    The effect of the microstructure heterogeneity on the tensile plastic deformation characteristic of friction-stir-welded (FSW) dual-phase (DP) steel was investigated for the potential applications on the lightweight design of vehicles. Friction-stir-welded specimens with a butt joint configuration were prepared, and quasi-static tensile tests were conducted, to evaluate the tensile properties of DP980 dual-phase steels. The friction-stir welding led to the formation of martensite and a significant hardness rise in the stir zone (SZ), but the presence of a soft zone in the heat-affected zone (HAZ) was caused by tempering of the pre-existing martensite. Owing to the appearance of severe soft zone, DP980 FSW joint showed almost 93% joint efficiency with the view-point of ultimate tensile strength and relatively low ductility than the base metal (BM). The local tensile deformation characteristic of the FSW joints was also examined using the digital image correlation (DIC) methodology by mapping the global and local strain distribution, and was subsequently analyzed by mechanics calculation. It is found that the tensile deformation of the FSW joints is highly heterogeneous, leading to a significant decrease in global ductility. The HAZ of the joints is the weakest region where the strain localizes early, and this localization extends until fracture with a strain near 30%, while the strain in the SZ and BM is only 1% and 4%, respectively. Local constitutive properties in different heterogeneous regions through the friction-stir-welded joint was also briefly evaluated by assuming iso-stress conditions. The local stress-strain curves of individual weld zones provide a clear indication of the heterogeneity of the local mechanical properties. PMID:28793720

  13. An Evaluation of Global and Local Tensile Properties of Friction-Stir Welded DP980 Dual-Phase Steel Joints Using a Digital Image Correlation Method.

    PubMed

    Lee, Hyoungwook; Kim, Cheolhee; Song, Jung Han

    2015-12-04

    The effect of the microstructure heterogeneity on the tensile plastic deformation characteristic of friction-stir-welded (FSW) dual-phase (DP) steel was investigated for the potential applications on the lightweight design of vehicles. Friction-stir-welded specimens with a butt joint configuration were prepared, and quasi-static tensile tests were conducted, to evaluate the tensile properties of DP980 dual-phase steels. The friction-stir welding led to the formation of martensite and a significant hardness rise in the stir zone (SZ), but the presence of a soft zone in the heat-affected zone (HAZ) was caused by tempering of the pre-existing martensite. Owing to the appearance of severe soft zone, DP980 FSW joint showed almost 93% joint efficiency with the view-point of ultimate tensile strength and relatively low ductility than the base metal (BM). The local tensile deformation characteristic of the FSW joints was also examined using the digital image correlation (DIC) methodology by mapping the global and local strain distribution, and was subsequently analyzed by mechanics calculation. It is found that the tensile deformation of the FSW joints is highly heterogeneous, leading to a significant decrease in global ductility. The HAZ of the joints is the weakest region where the strain localizes early, and this localization extends until fracture with a strain near 30%, while the strain in the SZ and BM is only 1% and 4%, respectively. Local constitutive properties in different heterogeneous regions through the friction-stir-welded joint was also briefly evaluated by assuming iso-stress conditions. The local stress-strain curves of individual weld zones provide a clear indication of the heterogeneity of the local mechanical properties.

  14. Frequency characteristics of vibration generated by dual acoustic radiation force for estimating viscoelastic properties of biological tissues

    NASA Astrophysics Data System (ADS)

    Watanabe, Ryoichi; Arakawa, Mototaka; Kanai, Hiroshi

    2018-07-01

    We proposed a new method for estimating the viscoelastic property of the local region of a sample. The viscoelastic parameters of the phantoms simulating the biological tissues were quantitatively estimated by analyzing the frequency characteristics of displacement generated by acoustic excitation. The samples were locally strained by irradiating them with the ultrasound simultaneously generated from two point-focusing transducers by applying the sum of two signals with slightly different frequencies of approximately 1 MHz. The surface of a phantom was excited in the frequency range of 20–2,000 Hz, and its displacement was measured. The frequency dependence of the acceleration provided by the acoustic radiation force was also measured. From these results, we determined the frequency characteristics of the transfer function from the stress to the strain and estimated the ratio of the elastic modulus to the viscosity modulus (K/η) by fitting the data to the Maxwell model. Moreover, the elastic modulus K was separately estimated from the measured sound velocity and density of the phantom, and the viscosity modulus η was evaluated by substituting the estimated elastic modulus into the obtained K/η ratio.

  15. Dual-Energy Micro-CT Functional Imaging of Primary Lung Cancer in Mice Using Gold and Iodine Nanoparticle Contrast Agents: A Validation Study

    PubMed Central

    Ashton, Jeffrey R.; Clark, Darin P.; Moding, Everett J.; Ghaghada, Ketan; Kirsch, David G.; West, Jennifer L.; Badea, Cristian T.

    2014-01-01

    Purpose To provide additional functional information for tumor characterization, we investigated the use of dual-energy computed tomography for imaging murine lung tumors. Tumor blood volume and vascular permeability were quantified using gold and iodine nanoparticles. This approach was compared with a single contrast agent/single-energy CT method. Ex vivo validation studies were performed to demonstrate the accuracy of in vivo contrast agent quantification by CT. Methods Primary lung tumors were generated in LSL-KrasG12D; p53FL/FL mice. Gold nanoparticles were injected, followed by iodine nanoparticles two days later. The gold accumulated in tumors, while the iodine provided intravascular contrast. Three dual-energy CT scans were performed–two for the single contrast agent method and one for the dual contrast agent method. Gold and iodine concentrations in each scan were calculated using a dual-energy decomposition. For each method, the tumor fractional blood volume was calculated based on iodine concentration, and tumor vascular permeability was estimated based on accumulated gold concentration. For validation, the CT-derived measurements were compared with histology and inductively-coupled plasma optical emission spectroscopy measurements of gold concentrations in tissues. Results Dual-energy CT enabled in vivo separation of gold and iodine contrast agents and showed uptake of gold nanoparticles in the spleen, liver, and tumors. The tumor fractional blood volume measurements determined from the two imaging methods were in agreement, and a high correlation (R2 = 0.81) was found between measured fractional blood volume and histology-derived microvascular density. Vascular permeability measurements obtained from the two imaging methods agreed well with ex vivo measurements. Conclusions Dual-energy CT using two types of nanoparticles is equivalent to the single nanoparticle method, but allows for measurement of fractional blood volume and permeability with a

  16. Guinea Pig Oxygen-Sensing and Carotid Body Functional Properties

    PubMed Central

    Gonzalez-Obeso, Elvira; Docio, Inmaculada; Olea, Elena; Cogolludo, Angel; Obeso, Ana; Rocher, Asuncion; Gomez-Niño, Angela

    2017-01-01

    Mammals have developed different mechanisms to maintain oxygen supply to cells in response to hypoxia. One of those mechanisms, the carotid body (CB) chemoreceptors, is able to detect physiological hypoxia and generate homeostatic reflex responses, mainly ventilatory and cardiovascular. It has been reported that guinea pigs, originally from the Andes, have a reduced ventilatory response to hypoxia compared to other mammals, implying that CB are not completely functional, which has been related to genetically/epigenetically determined poor hypoxia-driven CB reflex. This study was performed to check the guinea pig CB response to hypoxia compared to the well-known rat hypoxic response. These experiments have explored ventilatory parameters breathing different gases mixtures, cardiovascular responses to acute hypoxia, in vitro CB response to hypoxia and other stimuli and isolated guinea pig chemoreceptor cells properties. Our findings show that guinea pigs are hypotensive and have lower arterial pO2 than rats, probably related to a low sympathetic tone and high hemoglobin affinity. Those characteristics could represent a higher tolerance to hypoxic environment than other rodents. We also find that although CB are hypo-functional not showing chronic hypoxia sensitization, a small percentage of isolated carotid body chemoreceptor cells contain tyrosine hydroxylase enzyme and voltage-dependent K+ currents and therefore can be depolarized. However hypoxia does not modify intracellular Ca2+ levels or catecholamine secretion. Guinea pigs are able to hyperventilate only in response to intense acute hypoxic stimulus, but hypercapnic response is similar to rats. Whether other brain areas are also activated by hypoxia in guinea pigs remains to be studied. PMID:28533756

  17. Guinea Pig Oxygen-Sensing and Carotid Body Functional Properties.

    PubMed

    Gonzalez-Obeso, Elvira; Docio, Inmaculada; Olea, Elena; Cogolludo, Angel; Obeso, Ana; Rocher, Asuncion; Gomez-Niño, Angela

    2017-01-01

    Mammals have developed different mechanisms to maintain oxygen supply to cells in response to hypoxia. One of those mechanisms, the carotid body (CB) chemoreceptors, is able to detect physiological hypoxia and generate homeostatic reflex responses, mainly ventilatory and cardiovascular. It has been reported that guinea pigs, originally from the Andes, have a reduced ventilatory response to hypoxia compared to other mammals, implying that CB are not completely functional, which has been related to genetically/epigenetically determined poor hypoxia-driven CB reflex. This study was performed to check the guinea pig CB response to hypoxia compared to the well-known rat hypoxic response. These experiments have explored ventilatory parameters breathing different gases mixtures, cardiovascular responses to acute hypoxia, in vitro CB response to hypoxia and other stimuli and isolated guinea pig chemoreceptor cells properties. Our findings show that guinea pigs are hypotensive and have lower arterial pO 2 than rats, probably related to a low sympathetic tone and high hemoglobin affinity. Those characteristics could represent a higher tolerance to hypoxic environment than other rodents. We also find that although CB are hypo-functional not showing chronic hypoxia sensitization, a small percentage of isolated carotid body chemoreceptor cells contain tyrosine hydroxylase enzyme and voltage-dependent K + currents and therefore can be depolarized. However hypoxia does not modify intracellular Ca 2+ levels or catecholamine secretion. Guinea pigs are able to hyperventilate only in response to intense acute hypoxic stimulus, but hypercapnic response is similar to rats. Whether other brain areas are also activated by hypoxia in guinea pigs remains to be studied.

  18. Physicochemical and functional properties of peeled and unpeeled pumpkin flour.

    PubMed

    Noor Aziah, A A; Komathi, C A

    2009-09-01

    This study was intended to investigate the potential of peeled and unpeeled pumpkin pulp as a raw material for the production of flour that could be used in composite blend with wheat flour or as a functional ingredient in food products. The peeled and unpeeled pumpkin pulp were soaked in sodium metabisulphite solution, sliced and dried overnight in a hot air oven, followed by milling into peeled pumpkin pulp flour (PPPF) and unpeeled pumpkin pulp flour (UPPF), respectively. The flours were then evaluated for physicochemical attributes (color, proximate compositions, and water activity) and functional properties (water holding capacity and oil holding capacity), in comparison to the commercial wheat flour. PPPF and UPPF were observed to be more attractive in terms of color than wheat flour, as indicated by the significantly higher results (P or= 0.05) was shown in water holding capacity of PPPF and wheat flour. However, the oil holding capacity of PPPF and UPPF was shown to be significantly higher (P

  19. Dynamic Seeding of Perfusing Human Umbilical Vein Endothelial Cells (HUVECs) onto Dual-Function Cell Adhesion Ligands: Arg-Gly-Asp (RGD)-Streptavidin and Biotinylated Fibronectin

    PubMed Central

    Anamelechi, Charles C.; Clermont, Edward C.; Novak, Matthew T.; Reichert, William M.

    2014-01-01

    Surfaces decorated with high affinity ligands can be used to facilitate rapid attachment of endothelial cells; however, standard equilibrium cell detachment studies are poorly suited for assessing these initial adhesion events. Here, a dynamic seeding and cell retention method was used to examine the initial attachment of perfusing human umbilical vein endothelial cells (HUVECs) to bare Teflon-AF substrates, substrates pre-adsorbed with fibronectin alone, or substrates co-pre-adsorbed with two dual-function cell-adhesion ligands: biotinylated fibronectin (bFN) and RGD-streptavidin mutant (RGD-SA). Cell attachment was evaluated as a function of cell trypsinization (integrin digestion), surface protein formulation, and cell perfusion rate. Surfaces co-pre-adsorbed with bFN and RGD-SA showed the highest density of attached cells after 8 min of perfusion and the highest percent retention when subjected to shear flow at 60 dynes/cm2 for 2 min. Surfaces with no ligand treatment showed the lowest cell attachment and retention under flow in all cases. HUVECs trypsinized with mild 0.025% trypsin/ethylenediaminetetraacetic acid (EDTA) showed greater cell adhesion after perfusion and higher percent retention after shear flow than those trypsinized using harsher 0.05% trypsin/EDTA. The preferential affinities of the two dual-function ligands for α5β1 and αvβ3 integrins were also examined by surface plasmon resonance (SPR) spectroscopy. The dynamic cell seeding studies confirmed that the dual-function ligand system promotes HUVEC adhesion and retention at short time points when tested using a perfusion assay. SPR studies showed that the two ligands exhibited equal affinity for both α5β1 and αvβ3 integrins but that the combined ligands bound more total integrins than the two ligands tested separately. PMID:19348476

  20. Dual-enhanced photothermal conversion properties of reduced graphene oxide-coated gold superparticles for light-triggered acoustic and thermal theranostics†

    PubMed Central

    Lin, Li-Sen; Yang, Xiangyu; Niu, Gang

    2017-01-01

    A rational design of highly efficient photothermal agents that possess excellent light-to-heat conversion properties is a fascinating topic in nanotheranostics. Herein, we present a facile route to fabricate size-tunable reduced graphene oxide (rGO)-coated gold superparticles (rGO-GSPs) and demonstrate their dual-enhanced photothermal conversion properties for photoacoustic imaging and photothermal therapy. For the first time, graphene oxide (GO) was directly used as an emulsifying agent for the preparation of gold superparticles (GSPs) with near-infrared absorption by the emulsion method. Moreover, GO spontaneously deposited on the surface of GSPs could also act as the precursor of the rGO shell. Importantly, both the plasmonic coupling of the self-assembled gold nanoparticles and the interaction between GSPs and rGO endow rGO-GSPs with enhanced photothermal conversion properties, allowing rGO-GSPs to be used for sensitive photoacoustic detection and efficient photothermal ablation of tumours in vivo. This study provides a facile approach to prepare colloidal superparticles–graphene hybrid nanostructures and will pave the way toward the design and optimization of photothermal nanomaterials with improved properties for theranostic applications. PMID:26726809

  1. The Influence of Mo, Cr and B Alloying on Phase Transformation and Mechanical Properties in Nb Added High Strength Dual Phase Steels

    NASA Astrophysics Data System (ADS)

    Girina, O.; Fonstein, N.; Yakubovsky, O.; Panahi, D.; Bhattacharya, D.; Jansto, S.

    The influence of Nb, Mo, Cr and B on phase transformations and mechanical properties are studied in a 0.15C-2.0Mn-0.3Si-0.020Ti dual phase steel separately and in combination. The formation and decomposition of austenite together with recrystallization of ferrite are evaluated by dilatometry and constructed CCT-diagrams in laboratory processed cold rolled material cooled after full austenitization and from intercritical temperature range. The effect of alloying elements on formation of austenite through their effect on initial hot rolled structure is taken into account. The interpretation of phase transformations during heating and cooling is supported by metallography. The effect of alloying elements on mechanical properties and structure are evaluated by annealing simulations. It has been shown that mechanical properties are strongly influenced by alloying additions such as Nb, Mo, Cr and B through their effect on ferrite formation during continuous cooling and corresponding enrichment of remaining austenite by carbon. Depending on combined effect of these alloying elements, different phase transformations can be promoted during cooling. This allows controlling of final microstructural constituents and mechanical properties.

  2. Novel Functional Properties of Drosophila CNS Glutamate Receptors

    SciTech Connect

    Li, Yan; Dharkar, Poorva; Han, Tae-Hee

    Phylogenetic analysis reveals AMPA, kainate, and NMDA receptor families in insect genomes, suggesting conserved functional properties corresponding to their vertebrate counterparts. However, heterologous expression of the Drosophila kainate receptor DKaiR1D and the AMPA receptor DGluR1A revealed novel ligand selectivity at odds with the classification used for vertebrate glutamate receptor ion channels (iGluRs). DKaiR1D forms a rapidly activating and desensitizing receptor that is inhibited by both NMDA and the NMDA receptor antagonist AP5; crystallization of the KaiR1D ligand-binding domain reveals that these ligands stabilize open cleft conformations, explaining their action as antagonists. Surprisingly, the AMPA receptor DGluR1A shows weak activation bymore » its namesake agonist AMPA and also by quisqualate. Crystallization of the DGluR1A ligand-binding domain reveals amino acid exchanges that interfere with binding of these ligands. The unexpected ligand-binding profiles of insect iGluRs allows classical tools to be used in novel approaches for the study of synaptic regulation.« less

  3. Physicochemical and functional properties of gelatin extracted from Yak skin.

    PubMed

    Xu, Mengqi; Wei, Lixin; Xiao, Yuancan; Bi, Hongtao; Yang, Hongxia; Du, Yuzhi

    2017-02-01

    Different molecular weight distribution (MWD) gelatin was extracted from Yak skin after enzymatic pretreatments and their physicochemical and functional properties (SDS-PAGE, UV-vis absorption spectra, DSC, FT-IR, Amino acid analysis, AFM, emulsibility and foamability) were analyzed. The gelatin was extracted by pepsin and got different MWD of Yak skin gelatin by controlling the enzymolysis time. The SDS-PAGE showed the MWD of the Yak skin gelatin. The UV-vis absorption turned out that the broad MWD of Yak skin gelatin had a higher maximum absorption peaks. The FT-IR and AFM indicated that the gelatin structures and microstructures changed with the change of the MWD. The broad MWD of the Yak skin gelatin had a higher denaturation temperature (T D ), and it was higher than most of the other mammals and marine biological gelatin. The broad MWD gelatin also had higher imino acids (proline and hydroxyproline) contents and lower foamability and emulsibility compared to the narrow MWD gelatin. These findings, obtained for the first time for Yak skin gelatin, showed that it has great potential for application as an alternative to commercial gelatin due to its good thermotolerance, particularly in the applications of the biological materials, stabilizer of thermo-tolerant and so on. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Novel Functional Properties of Drosophila CNS Glutamate Receptors.

    PubMed

    Li, Yan; Dharkar, Poorva; Han, Tae-Hee; Serpe, Mihaela; Lee, Chi-Hon; Mayer, Mark L

    2016-12-07

    Phylogenetic analysis reveals AMPA, kainate, and NMDA receptor families in insect genomes, suggesting conserved functional properties corresponding to their vertebrate counterparts. However, heterologous expression of the Drosophila kainate receptor DKaiR1D and the AMPA receptor DGluR1A revealed novel ligand selectivity at odds with the classification used for vertebrate glutamate receptor ion channels (iGluRs). DKaiR1D forms a rapidly activating and desensitizing receptor that is inhibited by both NMDA and the NMDA receptor antagonist AP5; crystallization of the KaiR1D ligand-binding domain reveals that these ligands stabilize open cleft conformations, explaining their action as antagonists. Surprisingly, the AMPA receptor DGluR1A shows weak activation by its namesake agonist AMPA and also by quisqualate. Crystallization of the DGluR1A ligand-binding domain reveals amino acid exchanges that interfere with binding of these ligands. The unexpected ligand-binding profiles of insect iGluRs allows classical tools to be used in novel approaches for the study of synaptic regulation. VIDEO ABSTRACT. Published by Elsevier Inc.

  5. Yellow Mealworm Protein for Food Purposes - Extraction and Functional Properties

    PubMed Central

    Zhao, Xue; Vázquez-Gutiérrez, José Luis; Johansson, Daniel P.; Landberg, Rikard; Langton, Maud

    2016-01-01

    A protocol for extraction of yellow mealworm larvae proteins was established, conditions were evaluated and the resulting protein extract was characterised. The freeze-dried yellow mealworm larvae contained around 33% fat, 51% crude protein and 43% true protein on a dry matter basis. The true protein content of the protein extract was about 75%, with an extraction rate of 70% under optimised extraction conditions using 0.25 M NaOH, a NaOH solution:ethanol defatted worm ratio of 15:1 mL/g, 40°C for 1 h and extraction twice. The protein extract was a good source of essential amino acids. The lowest protein solubility in distilled water solution was found between pH 4 and 5, and increased with either increasing or decreasing pH. Lower solubility was observed in 0.5 M NaCl solution compared with distilled water. The rheological tests indicated that temperature, sample concentration, addition of salt and enzyme, incubation time and pH alterations influenced the elastic modulus of yellow mealworm protein extract (YMPE). These results demonstrate that the functional properties of YMPE can be modified for different food applications. PMID:26840533

  6. Dual-functional transdermal drug delivery system with controllable drug loading based on thermosensitive poloxamer hydrogel for atopic dermatitis treatment

    NASA Astrophysics Data System (ADS)

    Wang, Wenyi; Wat, Elaine; Hui, Patrick C. L.; Chan, Ben; Ng, Frency S. F.; Kan, Chi-Wai; Wang, Xiaowen; Hu, Huawen; Wong, Eric C. W.; Lau, Clara B. S.; Leung, Ping-Chung

    2016-04-01

    The treatment of atopic dermatitis (AD) has long been viewed as a problematic issue by the medical profession. Although a wide variety of complementary therapies have been introduced, they fail to combine the skin moisturizing and drug supply for AD patients. This study reports the development of a thermo-sensitive Poloxamer 407/Carboxymethyl cellulose sodium (P407/CMCs) composite hydrogel formulation with twin functions of moisture and drug supply for AD treatment. It was found that the presence of CMCs can appreciably improve the physical properties of P407 hydrogel, which makes it more suitable for tailored drug loading. The fabricated P407/CMCs composite hydrogel was also characterized in terms of surface morphology by field emission scanning electron microscopy (FE-SEM), rheological properties by a rheometer, release profile in vitro by dialysis method and cytotoxicity test. More importantly, the findings from transdermal drug delivery behavior revealed that P407/CMCs showed desirable percutaneous performance. Additionally, analysis of cytotoxicity test suggested that P407/CMCs composite hydrogel is a high-security therapy for clinical trials and thus exhibits a promising way to treat AD with skin moisturizing and medication.

  7. Dual-functional transdermal drug delivery system with controllable drug loading based on thermosensitive poloxamer hydrogel for atopic dermatitis treatment

    PubMed Central

    Wang, Wenyi; Wat, Elaine; Hui, Patrick C. L.; Chan, Ben; Ng, Frency S. F.; Kan, Chi-Wai; Wang, Xiaowen; Hu, Huawen; Wong, Eric C. W.; Lau, Clara B. S.; Leung, Ping-Chung

    2016-01-01

    The treatment of atopic dermatitis (AD) has long been viewed as a problematic issue by the medical profession. Although a wide variety of complementary therapies have been introduced, they fail to combine the skin moisturizing and drug supply for AD patients. This study reports the development of a thermo-sensitive Poloxamer 407/Carboxymethyl cellulose sodium (P407/CMCs) composite hydrogel formulation with twin functions of moisture and drug supply for AD treatment. It was found that the presence of CMCs can appreciably improve the physical properties of P407 hydrogel, which makes it more suitable for tailored drug loading. The fabricated P407/CMCs composite hydrogel was also characterized in terms of surface morphology by field emission scanning electron microscopy (FE-SEM), rheological properties by a rheometer, release profile in vitro by dialysis method and cytotoxicity test. More importantly, the findings from transdermal drug delivery behavior revealed that P407/CMCs showed desirable percutaneous performance. Additionally, analysis of cytotoxicity test suggested that P407/CMCs composite hydrogel is a high-security therapy for clinical trials and thus exhibits a promising way to treat AD with skin moisturizing and medication. PMID:27090158

  8. Characterization of the anti-inflammatory properties of NCX 429, a dual-acting compound releasing nitric oxide and naproxen.

    PubMed

    Amoruso, Angela; Fresu, Luigia Grazia; Dalli, Jesmond; Miglietta, Daniela; Bardelli, Claudio; Federici Canova, Donata; Perretti, Mauro; Brunelleschi, Sandra

    2015-04-01

    Cyclooxygenase (COX)-inhibiting nitric oxide donors (CINODs) are a new class of drugs that structurally combine a COX inhibitor with a nitric oxide (NO) donating moiety. This combination reduces potential toxicity of the non-steroidal anti-inflammatory drugs (NSAIDs) whilst maintaining the analgesic and anti-inflammatory effects. The present study was undertaken to investigate the anti-inflammatory effects of NCX 429, a naproxen-based CINOD, and to assess the additional properties of NO donation beyond those related to naproxen. We evaluated the in vitro effects of NCX 429 on oxy-radical production, phagocytosis, cytokine release, MMP-9, PPARγ expression and NF-κB activation in human monocytes/MDM and compared to naproxen. Moreover, we compared the in vivo efficacy of NCX 429 and naproxen in a murine model of peritonitis. In all the experiments performed in vitro, NCX 429 reduced the inflammatory responses with equal or higher efficacy compared to naproxen. Moreover, in in vivo experiments, NCX 429, at the lowest dose tested, was able to significantly inhibit cell influx in response to IL-1β administration although naproxen was found to be more potent than NCX 429 at reducing PGE2 in inflammatory exudates. These results demonstrate that both in vitro and in vivo--in a murine model of peritonitis--NCX 429 elicits significant anti-inflammatory activity, beyond the simple COX inhibition or pure NO release. Therefore, NO donation along with COX inhibition may represent a strategy for investigating inflammatory diseases in which pain and function are not fully resolved by analgesics/anti-inflammatory drugs. © 2015.

  9. Dual-Function Au@Y2O3:Eu3+ Smart Film for Enhanced Power Conversion Efficiency and Long-Term Stability of Perovskite Solar Cells.

    PubMed

    Kim, Chang Woo; Eom, Tae Young; Yang, In Seok; Kim, Byung Su; Lee, Wan In; Kang, Yong Soo; Kang, Young Soo

    2017-07-28

    In the present study, a dual-functional smart film combining the effects of wavelength conversion and amplification of the converted wave by the localized surface plasmon resonance has been investigated for a perovskite solar cell. This dual-functional film, composed of Au nanoparticles coated on the surface of Y 2 O 3 :Eu 3+ phosphor (Au@Y 2 O 3 :Eu 3+ ) nanoparticle monolayer, enhances the solar energy conversion efficiency to electrical energy and long-term stability of photovoltaic cells. Coupling between the Y 2 O 3 :Eu 3+ phosphor monolayer and ultraviolet solar light induces the latter to be converted into visible light with a quantum yield above 80%. Concurrently, the Au nanoparticle monolayer on the phosphor nanoparticle monolayer amplifies the converted visible light by up to 170%. This synergy leads to an increased solar light energy conversion efficiency of perovskite solar cells. Simultaneously, the dual-function film suppresses the photodegradation of perovskite by UV light, resulting in long-term stability. Introducing the hybrid smart Au@Y 2 O 3 :Eu 3+ film in perovskite solar cells increases their overall solar-to-electrical energy conversion efficiency to 16.1% and enhances long-term stability, as compared to the value of 15.2% for standard perovskite solar cells. The synergism between the wavelength conversion effect of the phosphor nanoparticle monolayer and the wave amplification by the localized surface plasmon resonance of the Au nanoparticle monolayer in a perovskite solar cell is comparatively investigated, providing a viable strategy of broadening the solar spectrum utilization.

  10. Dual DNA binding property of ABA insensitive 3 like factors targeted to promoters responsive to ABA and auxin.

    PubMed

    Nag, Ronita; Maity, Manas Kanti; Dasgupta, Maitrayee

    2005-11-01

    The ABA responsive ABI3 and the auxin responsive ARF family of transcription factors bind the CATGCATG (Sph) and TGTCTC core motifs in ABA and auxin response elements (ABRE and AuxRE), respectively. Several evidences indicate ABI3s to act downstream to auxin too. Because DNA binding domain of ABI3s shows significant overlap with ARFs we enquired whether auxin responsiveness through ABI3s could be mediated by their binding to canonical AuxREs. Investigations were undertaken through in vitro gel mobility shift assays (GMSA) using the DNA binding domain B3 of PvAlf (Phaseolus vulgaris ABI3 like factor) and upstream regions of auxin responsive gene GH3 (-267 to -141) and ABA responsive gene Em (-316 to -146) harboring AuxRE and ABRE, respectively. We demonstrate that B3 domain of PvAlf could bind AuxRE only when B3 was associated with its flanking domain B2 (B2B3). Such strict requirement of B2 domain was not observed with ABRE, where B3 could bind with or without being associated with B2. This dual specificity in DNA binding of ABI3s was also demonstrated with nuclear extracts of cultured cells of Arachis hypogea. Supershift analysis of ABRE and AuxRE bound nuclear proteins with antibodies raised against B2B3 domains of PvAlf revealed that ABI3 associated complexes were detectable in association with both cis elements. Competition GMSA confirmed the same complexes to bind ABRE and AuxRE. This dual specificity of ABI3 like factors in DNA binding targeted to natural promoters responsive to ABA and auxin suggests them to have a potential role in conferring crosstalk between these two phytohormones.

  11. Effect of hot-dip galvanizing processes on the microstructure and mechanical properties of 600-MPa hot-dip galvanized dual-phase steel

    NASA Astrophysics Data System (ADS)

    Kuang, Chun-fu; Zheng, Zhi-wang; Wang, Min-li; Xu, Quan; Zhang, Shen-gen

    2017-12-01

    A C-Mn dual-phase steel was soaked at 800°C for 90 s and then either rapidly cooled to 450°C and held for 30 s (process A) or rapidly cooled to 350°C and then reheated to 450°C (process B) to simulate the hot-dip galvanizing process. The influence of the hot-dip galvanizing process on the microstructure and mechanical properties of 600-MPa hot-dip galvanized dual-phase steel (DP600) was investigated using optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and tensile tests. The results showed that, in the case of process A, the microstructure of DP600 was composed of ferrite, martensite, and a small amount of bainite. The granular bainite was formed in the hot-dip galvanizing stage, and martensite islands were formed in the final cooling stage after hot-dip galvanizing. By contrast, in the case of process B, the microstructure of the DP600 was composed of ferrite, martensite, bainite, and cementite. In addition, compared with the yield strength (YS) of the DP600 annealed by process A, that for the DP600 annealed by process B increased by approximately 50 MPa because of the tempering of the martensite formed during rapid cooling. The work-hardening coefficient ( n value) of the DP600 steel annealed by process B clearly decreased because the increase of the YS affected the computation result for the n value. However, the ultimate tensile strength (UTS) and elongation ( A 80) of the DP600 annealed by process B exhibited less variation compared with those of the DP600 annealed by process A. Therefore, DP600 with excellent comprehensive mechanical properties (YS = 362 MPa, UTS = 638 MPa, A 80 = 24.3%, n = 0.17) was obtained via process A.

  12. A facile method to prepare dual-functional membrane for efficient oil removal and in situ reversible mercury ions adsorption from wastewater

    NASA Astrophysics Data System (ADS)

    Zhang, Qingdong; Liu, Na; Cao, Yingze; Zhang, Weifeng; Wei, Yen; Feng, Lin; Jiang, Lei

    2018-03-01

    In this work, a novel thiol covered polyamide (nylon 66) microfiltration membrane was fabricated by combining mussel-inspired chemistry and coupling reaction, which owns excellent dual-function that can simultaneously remove oil from water efficiently and adsorb the mercury ions contained in the wastewater reversibly. Such membrane exhibited high oil/water separation efficiency, outstanding mercury adsorption ability, and good stability. Moreover, it can be regenerated in nitric acid solution, and maintain its good adsorption performance. The as-prepared membrane showed great potentials for water purification to reduce the heavy metal ion pollution and complicated industrial oily wastewater and living wastewater.

  13. Functional properties of LRRK2 mutations in Taiwanese Parkinson disease.

    PubMed

    Chang, Kuo-Hsuan; Chen, Chiung-Mei; Lin, Chih-Hsin; Chang, Wen-Teng; Jiang, Pei-Ru; Hsiao, Ya-Chin; Wu, Yih-Ru; Lee-Chen, Guey-Jen

    2017-03-01

    Leucine-rich repeat kinase 2 (LRRK2) is a large protein encoding multiple functional domains. Mutations within different LRRK2 domains have been considered to be involved in the development of Parkinson disease by different mechanisms. Our previous study found three LRRK2 mutations-p.R767H, p.S885N, and p.R1441H-in Taiwanese patients with Parkinson disease. We evaluated the functional properties of LRRK2 p.R767H, p.S885N, and p.R1441H mutations by overexpressing them in human embryonic kidney 293 and neuroblastoma SK-N-SH cells. The common p.G2019S mutation in the kinase domain was included for comparison. In 293 cells, overexpressed p.R1441H-but not p.R767H, p.S885N, or p.G2019-increased GTP binding affinity to prolong the active state. Overexpressed p.R1441H and p.G2019S generated inclusions in 293 cells. In SK-N-SH cells, the α-synuclein was coexpressed with wild type as well as mutated p.R767H, p.S885N, p.R1441H, and p.G2019 LRRK2 proteins. Part of the perinuclear inclusions formed by p.R1441H and p.G2019S were colocalized with α-synuclein. Additionally, p.S885N and p.R1441H mutations caused reduced interaction between LRRK2 and ARHGEF7, a putative guanine nucleotide exchange factor for LRRK2, whereas this interaction was well preserved in p.R767H and p.G2019S mutations. Our study suggests that p.R1441H protein facilitates the formation of intracellular inclusions, compromises GTP hydrolysis by increasing its affinity for GTP, and reduces its interaction with ARHGEF7. Copyright © 2016. Published by Elsevier B.V.

  14. The Dual Functions of WLIM1a in Cell Elongation and Secondary Wall Formation in Developing Cotton Fibers[C][W

    PubMed Central

    Han, Li-Bo; Li, Yuan-Bao; Wang, Hai-Yun; Wu, Xiao-Min; Li, Chun-Li; Luo, Ming; Wu, Shen-Jie; Kong, Zhao-Sheng; Pei, Yan; Jiao, Gai-Li; Xia, Gui-Xian

    2013-01-01

    LIN-11, Isl1 and MEC-3 (LIM)-domain proteins play pivotal roles in a variety of cellular processes in animals, but plant LIM functions remain largely unexplored. Here, we demonstrate dual roles of the WLIM1a gene in fiber development in upland cotton (Gossypium hirsutum). WLIM1a is preferentially expressed during the elongation and secondary wall synthesis stages in developing fibers. Overexpression of WLIM1a in cotton led to significant changes in fiber length and secondary wall structure. Compared with the wild type, fibers of WLIM1a-overexpressing plants grew longer and formed a thinner and more compact secondary cell wall, which contributed to improved fiber strength and fineness. Functional studies demonstrated that (1) WLIM1a acts as an actin bundler to facilitate elongation of fiber cells and (2) WLIM1a also functions as a transcription factor to activate expression of Phe ammonia lyase–box genes involved in phenylpropanoid biosynthesis to build up the secondary cell wall. WLIM1a localizes in the cytosol and nucleus and moves into the nucleus in response to hydrogen peroxide. Taken together, these results demonstrate that WLIM1a has dual roles in cotton fiber development, elongation, and secondary wall formation. Moreover, our study shows that lignin/lignin-like phenolics may substantially affect cotton fiber quality; this finding may guide cotton breeding for improved fiber traits. PMID:24220634

  15. Ultrasensitive colorimetric immunoassay for hCG detection based on dual catalysis of Au@Pt core-shell nanoparticle functionalized by horseradish peroxidase

    NASA Astrophysics Data System (ADS)

    Wang, Weiguo; Zou, Yake; Yan, Jinwu; Liu, Jing; Chen, Huixiong; Li, Shan; Zhang, Lei

    2018-03-01

    In this paper, an ultrasensitive colorimetric biosensor for human chorionic gonadotrophin (hCG) detection was designed from bottom-up method based on the dual catalysis of the horseradish peroxidase (HRP) and Au@Pt nanoparticles (NPs) relative to H2O2-TEM system. HRP and monoclonal mouse anti-hCG antibody (β-submit, mAb1) were co-immobilized onto the Au@Pt NP surface to improve catalytic efficiency and specificity, which formed a dual functionalized Au@Pt-HRP probe with the mean size of 42.8 nm (D50). The colorimetric immunoassay was developed for the hCG detection, and the Au@Pt-HRP probe featured a higher sensitivity in the concentration range of 0.4-12.8 IU L- 1 with a low limit of detection (LOD) of 0.1 IU L- 1 compared with the LODs of 0.8 IU L- 1 for BA-ELISA and of 2.0 IU L- 1 for Au@Pt, which indicated that the Au@Pt-HRP probe possessed higher catalytic efficiency with 2.8-fold increase over Au@Pt and 33.8-fold increase over HRP. Also, the Au@Pt-HRP probe exhibited good precision and reproducibility, high specificity and acceptable accuracy with CV being less than 15%. The dual functionalized Au@Pt-HRP probe as a type of signal amplified method was firstly applied in the colorimetric immunoassay for the hCG detection.

  16. Semantic Web Service Delivery in Healthcare Based on Functional and Non-Functional Properties.

    PubMed

    Schweitzer, Marco; Gorfer, Thilo; Hörbst, Alexander

    2017-01-01

    In the past decades, a lot of endeavor has been made on the trans-institutional exchange of healthcare data through electronic health records (EHR) in order to obtain a lifelong, shared accessible health record of a patient. Besides basic information exchange, there is a growing need for Information and Communication Technology (ICT) to support the use of the collected health data in an individual, case-specific workflow-based manner. This paper presents the results on how workflows can be used to process data from electronic health records, following a semantic web service approach that enables automatic discovery, composition and invocation of suitable web services. Based on this solution, the user (physician) can define its needs from a domain-specific perspective, whereas the ICT-system fulfills those needs with modular web services. By involving also non-functional properties for the service selection, this approach is even more suitable for the dynamic medical domain.

  17. Dual-modality imaging

    NASA Astrophysics Data System (ADS)

    Hasegawa, Bruce; Tang, H. Roger; Da Silva, Angela J.; Wong, Kenneth H.; Iwata, Koji; Wu, Max C.

    2001-09-01

    In comparison to conventional medical imaging techniques, dual-modality imaging offers the advantage of correlating anatomical information from X-ray computed tomography (CT) with functional measurements from single-photon emission computed tomography (SPECT) or with positron emission tomography (PET). The combined X-ray/radionuclide images from dual-modality imaging can help the clinician to differentiate disease from normal uptake of radiopharmaceuticals, and to improve diagnosis and staging of disease. In addition, phantom and animal studies have demonstrated that a priori structural information from CT can be used to improve quantification of tissue uptake and organ function by correcting the radionuclide data for errors due to photon attenuation, partial volume effects, scatter radiation, and other physical effects. Dual-modality imaging therefore is emerging as a method of improving the visual quality and the quantitative accuracy of radionuclide imaging for diagnosis of patients with cancer and heart disease.

  18. Dual blockade of HER2 in HER2-overexpressing tumor cells does not completely eliminate HER3 function.

    PubMed

    Garrett, Joan T; Sutton, Cammie R; Kuba, María Gabriela; Cook, Rebecca S; Arteaga, Carlos L

    2013-02-01

    Dual blockade of HER2 with trastuzumab and lapatinib or with pertuzumab is a superior treatment approach compared with single-agent HER2 inhibitors. However, many HER2-overexpressing breast cancers still escape from this combinatorial approach. Inhibition of HER2 and downstream phosphoinositide 3-kinase (PI3K)/AKT causes a transcriptional and posttranslational upregulation of HER3 which, in turn, counteracts the antitumor action of the HER2-directed therapies. We hypothesized that suppression of HER3 would synergize with dual blockade of HER2 in breast cancer cells sensitive and refractory to HER2 antagonists. Inhibition of HER2/HER3 in HER2(+) breast cancer cell lines was evaluated by Western blotting. We analyzed drug-induced apoptosis and two- and three-dimensional growth in vitro. Growth inhibition of PI3K was examined in vivo in xenografts treated with combinations of trastuzumab, lapatinib, and the HER3-neutralizing monoclonal antibody U3-1287. Treatment with U3-1287 blocked the upregulation of total and phosphorylated HER3 that followed treatment with lapatinib and trastuzumab and, in turn, enhanced the antitumor action of the combination against trastuzumab-sensitive and -resistant cells. Mice bearing HER2(+) xenografts treated with lapatinib, trastuzumab, and U3-1287 exhibited fewer recurrences and better survival than mice treated with lapatinib and trastuzumab. Dual blockade of HER2 with trastuzumab and lapatinib does not eliminate the compensatory upregulation of HER3. Therapeutic inhibitors of HER3 should be considered as part of multidrug combinations aimed at completely and rapidly disabling the HER2 network in HER2-overexpressing breast cancers.

  19. Influence of Al Addition Upon the Microstructure and Mechanical Property of Dual-Phase 9Cr-ODS Steels

    NASA Astrophysics Data System (ADS)

    Zhou, Xiaosheng; Ma, Zongqing; Yu, Liming; Huang, Yuan; Li, Huijun; Liu, Yongchang

    2018-06-01

    With Al addition, dual-phase oxide dispersion strengthened (ODS) steels consisting of martensite and ferrite are fabricated by spark plasma sintering. It is found that Al addition has a negligible effect on martensite lath size, while the amount and size of ferrite grains are related to the Al content. M23C6 (M = Fe, Cr) carbides have been identified within the ferrite grains or along ferrite boundaries. With increasing Al concentration, more fine Y-Al-O oxide nanoparticles are formed. Upon annealing treatment, homogeneous and refined distribution of ferrite grains is obtained, which may involve the particle-stimulated nucleation of recrystallization caused by the large sized M23C6. As Al is increased from 0.05 to 0.1 wt%, the tensile strength of the annealed steel is decreased, as well as its ductility. For the annealed 9Cr-ODS steel containing 0.1 wt% Al, in tensile loading the large sized M23C6 along ferrite boundaries would facilitate the cracking along boundaries between the hard annealed ferrite and soft annealed martensite, producing the mixed fracture of dimple and intergranular fracture.

  20. Gold Nanoparticles Grafted with PLL-b-PNIPAM: Interplay on Thermal/pH Dual-Response and Optical Properties.

    PubMed

    Li, Hui-Juan; Li, Peng-Yun; Li, Li-Ying; Haleem, Abdul; He, Wei-Dong

    2018-04-16

    Narrowly distributed poly(l-lysine- b - N -isopropylacrylamide) (PLL- b -PNIPAM) was prepared through ring-opening polymerization of ε-benzyloxycarbonyl-l-lysine N -carboxy-α-amino anhydride and atom transfer radical polymerization of NIPAM, followed with the removal of ε-benzyloxycarbonyl group. Then gold nanoparticles (AuNPs) grafted with PLL- b -PNIPAM (PNIPAM-PLL-AuNPs) were obtained by the reduction of chloroauric acid with sodium citrate in the presence of PLL- b -PNIPAM. PNIPAM-PLL-AuNPs and its precursors were thoroughly characterized by proton magnetic resonance spectroscope, Fourier transform infrared spectroscope, UV-vis spectroscope, transmission electron microscopy, dynamic light scattering, thermogravimetric analysis, and circular dichroism. The obtained PNIPAM-PLL-AuNPs exhibited high colloid stability even at strong alkaline (pH = 12) and acidic (pH = 2) conditions. The thermal and pH dual-responsive behaviors of the grafting PLL- b -PNIPAM chains was observed to be affected by AuNPs, while not for the secondary structure of PLL chains. Correspondingly, the surface plasmon resonance (SPR) of AuNPs was found to be sensitive to both pH value and temperature. A blue shift in the SPR happened both with increasing pH value and increasing temperature. The stimuli-response was reversible in heating-cooling cycles. The gold nanoparticles with both pH and temperature response may have potential applications in biomedical areas and biosensors.

  1. Beyond Zipf's Law: The Lavalette Rank Function and Its Properties.

    PubMed

    Fontanelli, Oscar; Miramontes, Pedro; Yang, Yaning; Cocho, Germinal; Li, Wentian

    Although Zipf's law is widespread in natural and social data, one often encounters situations where one or both ends of the ranked data deviate from the power-law function. Previously we proposed the Beta rank function to improve the fitting of data which does not follow a perfect Zipf's law. Here we show that when the two parameters in the Beta rank function have the same value, the Lavalette rank function, the probability density function can be derived analytically. We also show both computationally and analytically that Lavalette distribution is approximately equal, though not identical, to the lognormal distribution. We illustrate the utility of Lavalette rank function in several datasets. We also address three analysis issues on the statistical testing of Lavalette fitting function, comparison between Zipf's law and lognormal distribution through Lavalette function, and comparison between lognormal distribution and Lavalette distribution.

  2. Cytidine-stabilized gold nanocluster as a fluorescence turn-on and turn-off probe for dual functional detection of Ag(+) and Hg(2+).

    PubMed

    Zhang, Yuanyuan; Jiang, Hui; Wang, Xuemei

    2015-04-22

    In this study, we have developed a label-free, dual functional detection strategy for highly selective and sensitive determination of aqueous Ag(+) and Hg(2+) by using cytidine stabilized Au NCs and AuAg NCs as fluorescent turn-on and turn off probes, respectively. The Au NCs and AuAg NCs showed a remarkably rapid response and high selectivity for Ag(+) and Hg(2+) over other metal ions, and relevant detection limit of Ag(+) and Hg(2+) is ca. 10 nM and 30 nM, respectively. Importantly, the fluorescence enhanced Au NCs by doping Ag(+) can be conveniently reusable for the detection of Hg(2+) based on the corresponding fluorescence quenching. The sensing mechanism was based on the high-affinity metallophilic Hg(2+)-Ag(+) interaction, which effectively quenched the fluorescence of AuAg NCs. Furthermore, these fluorescent nanoprobes could be readily applied to Ag(+) and Hg(2+) detection in environmental water samples, indicating their possibility to be utilized as a convenient, dual functional, rapid response, and label-free fluorescence sensor for related environmental and health monitoring. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Spectral properties of four-time fermionic Green's functions

    DOE PAGES

    Shvaika, A. M.

    2016-09-01

    The spectral relations for the four-time fermionic Green's functions are derived in the most general case. The terms which correspond to the zero-frequency anomalies, known before only for the bosonic Green's functions, are separated and their connection with the second cumulants of the Boltzmann distribution function is elucidated. Furthermore, the high-frequency expansions of the four-time fermionic Green's functions are provided for different directions in the frequency space.

  4. Spectral properties of four-time fermionic Green's functions

    SciTech Connect

    Shvaika, A. M.

    The spectral relations for the four-time fermionic Green's functions are derived in the most general case. The terms which correspond to the zero-frequency anomalies, known before only for the bosonic Green's functions, are separated and their connection with the second cumulants of the Boltzmann distribution function is elucidated. Furthermore, the high-frequency expansions of the four-time fermionic Green's functions are provided for different directions in the frequency space.

  5. Quantitative structure-property relationships for chemical functional use and weight fractions in consumer articles

    EPA Science Inventory

    Chemical functional use -- the functional role a chemical plays in processes or products -- may be a useful heuristic for predicting human exposure potential in that it comprises information about the compound's likely physical properties and the product formulations or articles ...

  6. Quality Characteristics, Changes in Physiochemical Properties and Functional Properties of Camembert Cheese Containing Red Ginseng Powder

    PubMed Central

    Lee, Jai-Sung; Bae, Inhyu

    2018-01-01

    Effects of quality, physicochemical properties and antioxidants in Camembert cheese added with red ginseng powder (RGP) were investigated. Cheese samples were prepared with 0.05%, 0.10%, 0.15% and 0.20% RGP. and then monitored during ripening at 14°C for 28 d. The pH of the RGP amended treatment groups increased during the ripening period relative to the control (p<0.05). Moreover, the 1,2-Diphenyl-1-picrylhydrazyle (DPPH) was highest in the 0.15% RGP group from 21 d to 28 d. ABTS+ radical scavenging activity was increased just like DPPH as the ripening period passed, 0.10% treatment was highest at from 7 d to 21 d. 0.15% RGP was contents of ginsenosides : 10,999.7 ppm. The Free fatty acids (FFA), controls with 0.15% treatment, while the total fat (TF) and monounsaturated fat (MuSF) were higher in the control than the 0.15% RGP group (p<0.05). The total free amino acid (FAA) was increased in the control, and 0.15% RGP, and control was highest at then 0.15% RGP. The samples had average contents of fat and protein were 29% and 18-20% respectively. Additionally, the L* value decreased, while the a* and b* values increased as the amount of RGP added increased. Sensory evaluation revealed that texture and total acceptability were higher in the control group at 12 d. Although the addition of RGP did not exert a better effect on the ripening of the camembert cheese, but the ripening grade was similar to that of the common camembert cheese, and the additional function of the cheese was reinforced. Functional cheese could be developed. PMID:29725225

  7. Quality Characteristics, Changes in Physiochemical Properties and Functional Properties of Camembert Cheese Containing Red Ginseng Powder.

    PubMed

    Lee, Jai-Sung; Bae, Inhyu

    2018-02-01

    Effects of quality, physicochemical properties and antioxidants in Camembert cheese added with red ginseng powder (RGP) were investigated. Cheese samples were prepared with 0.05%, 0.10%, 0.15% and 0.20% RGP. and then monitored during ripening at 14°C for 28 d. The pH of the RGP amended treatment groups increased during the ripening period relative to the control ( p <0.05). Moreover, the 1,2-Diphenyl-1-picrylhydrazyle (DPPH) was highest in the 0.15% RGP group from 21 d to 28 d. ABTS + radical scavenging activity was increased just like DPPH as the ripening period passed, 0.10% treatment was highest at from 7 d to 21 d. 0.15% RGP was contents of ginsenosides : 10,999.7 ppm. The Free fatty acids (FFA), controls with 0.15% treatment, while the total fat (TF) and monounsaturated fat (MuSF) were higher in the control than the 0.15% RGP group ( p <0.05). The total free amino acid (FAA) was increased in the control, and 0.15% RGP, and control was highest at then 0.15% RGP. The samples had average contents of fat and protein were 29% and 18-20% respectively. Additionally, the L* value decreased, while the a* and b* values increased as the amount of RGP added increased. Sensory evaluation revealed that texture and total acceptability were higher in the control group at 12 d. Although the addition of RGP did not exert a better effect on the ripening of the camembert cheese, but the ripening grade was similar to that of the common camembert cheese, and the additional function of the cheese was reinforced. Functional cheese could be developed.

  8. Bioactive phytochemicals in wheat: Extraction, analysis, processing, and functional properties

    USDA-ARS?s Scientific Manuscript database

    Whole wheat provides a rich source of bioactive phytochemicals namely, phenolic acids, carotenoids, tocopherols, alkylresorcinols, arabinoxylans, benzoxazinoids, phytosterols, and lignans. This review provides information on the distribution, extractability, analysis, and nutraceutical properties of...

  9. Design of Functional Layered Oxide Materials Through Understanding Structure-Property Relationships

    NASA Astrophysics Data System (ADS)

    Strayer, Megan E.

    A fundamental understanding of structure-property relationships is imperative in the rational design of new materials for tailored applications. In this dissertation, structureproperty relationships are exploited in layered oxides and their composite materials. Recent advances in characterization techniques have allowed for more in-depth investigations into both the atomic level structure and properties of these materials. This dissertation focuses on understanding the structure-property relationships in supported catalytic systems and ferroelectric materials to aid in the rational design of functional materials. In Chapter 2, a correlation between the enthalpy of nanoparticle adsorption to oxide supports and the subsequent growth of these nanoparticles as a function of temperature is investigated. When deposited onto layered niobium oxide and tantalum oxide supports, rhodium hydroxide nanoparticles remain small and evenly dispersed upon heating to 750 °C. Using isothermal titration calorimetry, the bonding enthalpy of rhodium hydroxide nanoparticles to oxide supports is quantified for the first time under the wet synthetic conditions of catalyst preparation. Rh(OH)3 is concluded to have a strong, covalent interaction with the early transition metal oxide supports, and the interfacial bonding is hypothesized to occur through Rh - O - Nb bonding. Chapter 3 extends the studies in Chapter 2 to include supported metal, metal oxide, and metal hydroxide nanoparticles in the cobalt, nickel and copper triads. The data confirms a strong correlation between the heats of interaction and stability of the supported nanoparticles. Both experimental data and density functional theory calculations demonstrate that the support and nanoparticle compositions impact the heat of interaction and that the qualitative periodic trends of the metal bonding interaction are independent of the metal oxidation state. A strong bond is shown computationally to arise from the formation of mixed d

  10. A novel material detection algorithm based on 2D GMM-based power density function and image detail addition scheme in dual energy X-ray images.

    PubMed

    Pourghassem, Hossein

    2012-01-01

    Material detection is a vital need in dual energy X-ray luggage inspection systems at security of airport and strategic places. In this paper, a novel material detection algorithm based on statistical trainable models using 2-Dimensional power density function (PDF) of three material categories in dual energy X-ray images is proposed. In this algorithm, the PDF of each material category as a statistical model is estimated from transmission measurement values of low and high energy X-ray images by Gaussian Mixture Models (GMM). Material label of each pixel of object is determined based on dependency probability of its transmission measurement values in the low and high energy to PDF of three material categories (metallic, organic and mixed materials). The performance of material detection algorithm is improved by a maximum voting scheme in a neighborhood of image as a post-processing stage. Using two background removing and denoising stages, high and low energy X-ray images are enhanced as a pre-processing procedure. For improving the discrimination capability of the proposed material detection algorithm, the details of the low and high energy X-ray images are added to constructed color image which includes three colors (orange, blue and green) for representing the organic, metallic and mixed materials. The proposed algorithm is evaluated on real images that had been captured from a commercial dual energy X-ray luggage inspection system. The obtained results show that the proposed algorithm is effective and operative in detection of the metallic, organic and mixed materials with acceptable accuracy.

  11. Design, synthesis and antiviral evaluation of novel heteroarylcarbothioamide derivatives as dual inhibitors of HIV-1 reverse transcriptase-associated RNase H and RDDP functions.

    PubMed

    Corona, Angela; Onnis, Valentina; Deplano, Alessandro; Bianco, Giulia; Demurtas, Monica; Distinto, Simona; Cheng, Yung-Chi; Alcaro, Stefano; Esposito, Francesca; Tramontano, Enzo

    2017-08-31

    In the continuous effort to identify new HIV-1 inhibitors endowed with innovative mechanisms, the dual inhibition of different viral functions would provide a significant advantage against drug-resistant variants. The HIV-1 reverse transcriptase (RT)-associated ribonuclease H (RNase H) is the only viral-encoded enzymatic activity that still lacks an efficient inhibitor. We synthesized a library of 3,5-diamino-N-aryl-1H-pyrazole-4-carbothioamide and 4-amino-5-benzoyl-N-phenyl-2-(substituted-amino)-1H-pyrrole-3-carbothioamide derivatives and tested them against RNase H activity. We identified the pyrazolecarbothioamide derivative A15, able to inhibit viral replication and both RNase H and RNA-dependent DNA polymerase (RDDP) RT-associated activities in the low micromolar range. Docking simulations hypothesized its binding to two RT pockets. Site-directed mutagenesis experiments showed that, with respect to wt RT, V108A substitution strongly reduced A15 IC50 values (12.6-fold for RNase H inhibition and 4.7-fold for RDDP), while substitution A502F caused a 9.0-fold increase in its IC50 value for RNase H, not affecting the RDDP inhibition, reinforcing the hypothesis of a dual-site inhibition. Moreover, A15 retained good inhibition potency against three non-nucleoside RT inhibitor (NNRTI)-resistant enzymes, confirming a mode of action unrelated to NNRTIs and suggesting its potential as a lead compound for development of new HIV-1 RT dual inhibitors active against drug-resistant viruses. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. SU-F-T-660: Evaluating the Benefit of Using Dual-Function Fiducial Markers for In-Situ Delivery of Radiosenistizing Gold Nanoparticles During Image-Guided Radiotherapy

    SciTech Connect

    AlMansour, S; Chin, J; Sajo, E

    Purpose: Dual-function fiducials loaded with radiosensitizers, like gold nanoparticles (GNP), offer an innovative approach for ensuring geometric accuracy during image-guided radiotherapy (IGRT) and significantly increasing therapeutic efficacy due to controlled in-situ release of the radiosensitizers. This study retrospectively investigates the dosimetric benefit of using up to two such dual-function fiducial markers instead of traditional single function fiducials during IGRT. Methods: A computational code was developed to investigate the dosimetric benefit for 10 real patient tumor volumes of up to 6.5 cm diameter. The intra-tumoral space-time biodistribution of the GNP was modeled as in previous studies based on Fick’s second law.more » The corresponding dose-enhancement for each tumor voxel due to the GNP was also calculated for clinical 6MV beam configurations. Various loading concentrations (25–50 mg/g) were studied, as a function of GNP size, to determine potential for clinically significant dose enhancement. The time between initial implantation of dual-function fiducials to the beginning of radiotherapy was assumed to be 14 days as typical for many clinics. Results: A single dual-function fiducial could achieve at least a DEF of 1.2 for patients with tumors less than 1.4 cm diameter after 14 days. Replacing two single function fiducials with dual-function ones at the same locations achieved at least the required minimal DEF for tumors that are 2 cm diameter in 3 patients. The results also revealed dosimetrically better fiducial locations which could enable significant DEF when using one or two dual function fiducials. 2 nm sizes showed the most feasibility. Conclusion: The results highlight the potential of tumor sub-volume radiation boosting using GNP released from fiducials, and the ability to customize the DEF throughout the tumor by using two dual-function fiducials, varying the initial concentration and nanoparticle size. The results

  13. Dual-dye optical mapping after myocardial infarction: does the site of ventricular stimulation alter the properties of electrical propagation?

    PubMed

    Saba, Samir; Mathier, Michael A; Mehdi, Haider; Liu, Tong; Choi, Bum-Rak; London, Barry; Salama, Guy

    2008-02-01

    Myocardial infarction (MI) disrupts electrical conduction in affected ventricular areas. We investigated the effect of MI on the regional voltage and calcium (Ca) signals and their propagation properties, with special attention to the effect of the site of ventricular pacing on these properties. New Zealand White rabbits were divided into four study groups: sham-operated (C, n = 6), MI with no pacing (MI, n = 7), MI with right ventricular pacing (MI + RV, n = 6), and MI with BIV pacing (MI + BIV, n = 7). At 4 weeks, hearts were excised, perfused, and optically mapped. As previously shown, systolic and diastolic dilation of the LV were prevented by BIV pacing, as was the reduction in LV fractional shortening. Four weeks after MI, optical mapping revealed markedly reduced action potential amplitudes and conduction velocities (CV) in MI zones, and these increased gradually in the border zone and normal myocardial areas. Also, Ca transients were absent in the infarcted areas and increased gradually 3-5 mm from the border of the normal zone. Neither BIV nor RV pacing affected these findings in any of the MI, border, or normal zones. MI has profound effects on the regional electrical and Ca signals and on their propagation properties in this rabbit model. The absence of differences in these parameters by study group suggests that altering the properties of myocardial electrical conduction and Ca signaling are unlikely mechanisms by which BIV pacing confers its benefits. Further studies into the regional, cellular, and molecular benefits of BIV pacing are therefore warranted.

  14. Effects of Limited Hydrolysis and High-Pressure Homogenization on Functional Properties of Oyster Protein Isolates.

    PubMed

    Yu, Cuiping; Cha, Yue; Wu, Fan; Xu, Xianbing; Du, Ming

    2018-03-22

    In this study, the effects of limited hydrolysis and/or high-pressure homogenization (HPH) treatment in acid conditions on the functional properties of oyster protein isolates (OPI) were studied. Protein solubility, surface hydrophobicity, particle size distribution, zeta potential, foaming, and emulsifying properties were evaluated. The results showed that acid treatment led to the dissociation and unfolding of OPI. Subsequent treatment such as limited proteolysis, HPH, and their combination remarkably improved the functional properties of OPI. Acid treatment produced flexible aggregates, as well as reduced particle size and solubility. On the contrary, limited hydrolysis increased the solubility of OPI. Furthermore, HPH enhanced the effectiveness of the above treatments. The emulsifying and foaming properties of acid- or hydrolysis-treated OPI significantly improved. In conclusion, a combination of acid treatment, limited proteolysis, and HPH improved the functional properties of OPI. The improvements in the functional properties of OPI could potentiate the use of oyster protein and its hydrolysates in the food industry.

  15. Solid state protein monolayers: Morphological, conformational, and functional properties

    NASA Astrophysics Data System (ADS)

    Pompa, P. P.; Biasco, A.; Frascerra, V.; Calabi, F.; Cingolani, R.; Rinaldi, R.; Verbeet, M. Ph.; de Waal, E.; Canters, G. W.

    2004-12-01

    We have studied the morphological, conformational, and electron-transfer (ET) function of the metalloprotein azurin in the solid state, by a combination of physical investigation methods, namely atomic force microscopy, intrinsic fluorescence spectroscopy, and scanning tunneling microscopy. We demonstrate that a "solid state protein film" maintains its nativelike conformation and ET function, even after removal of the aqueous solvent.

  16. A triangular property of the associated Legendre functions

    NASA Technical Reports Server (NTRS)

    Fineschi, S.; Landi Degl'innocenti, E.

    1990-01-01

    A mathematical formula is introduced and proved which relates the associated Legendre functions with given nonnegative integral indices. The application of this formula in simplifying the calculation of collisional electron-atom cross sections higher than the dipole is mentioned. A proof of the stated identity using the Gegenbauer polynomials and their generating function is given.

  17. Properties of amaranth flour with functional oat products

    USDA-ARS?s Scientific Manuscript database

    Amaranth flour containing the essential amino acid, lysine, was composited with oat products that contain ß-glucan known for lowering blood cholesterol and preventing heart disease. The pasting and rheological properties of amaranth-oat composites were evaluated. The amaranth-Nutrim composites showe...

  18. Sensor Fusion Based on an Integrated Neural Network and Probability Density Function (PDF) Dual Kalman Filter for On-Line Estimation of Vehicle Parameters and States.

    PubMed

    Vargas-Melendez, Leandro; Boada, Beatriz L; Boada, Maria Jesus L; Gauchia, Antonio; Diaz, Vicente

    2017-04-29

    Vehicles with a high center of gravity (COG), such as light trucks and heavy vehicles, are prone to rollover. This kind of accident causes nearly 33 % of all deaths from passenger vehicle crashes. Nowadays, these vehicles are incorporating roll stability control (RSC) systems to improve their safety. Most of the RSC systems require the vehicle roll angle as a known input variable to predict the lateral load transfer. The vehicle roll angle can be directly measured by a dual antenna global positioning system (GPS), but it is expensive. For this reason, it is important to estimate the vehicle roll angle from sensors installed onboard in current vehicles. On the other hand, the knowledge of the vehicle's parameters values is essential to obtain an accurate vehicle response. Some of vehicle parameters cannot be easily obtained and they can vary over time. In this paper, an algorithm for the simultaneous on-line estimation of vehicle's roll angle and parameters is proposed. This algorithm uses a probability density function (PDF)-based truncation method in combination with a dual Kalman filter (DKF), to guarantee that both vehicle's states and parameters are within bounds that have a physical meaning, using the information obtained from sensors mounted on vehicles. Experimental results show the effectiveness of the proposed algorithm.

  19. The dual-specificity protein phosphatase DUSP9/MKP-4 is essential for placental function but is not required for normal embryonic development.

    PubMed

    Christie, Graham R; Williams, David J; Macisaac, Fiona; Dickinson, Robin J; Rosewell, Ian; Keyse, Stephen M

    2005-09-01

    To elucidate the physiological role(s) of DUSP9 (dual-specificity phosphatase 9), also known as MKP-4 (mitogen-activated protein kinase [MAPK] phosphatase 4), the gene was deleted in mice. Crossing male chimeras with wild-type females resulted in heterozygous (DUSP9(+/-)) females. However, when these animals were crossed with wild-type (DUSP9(+/y)) males none of the progeny carried the targeted DUSP9 allele, indicating that both female heterozygous and male null (DUSP9(-/y)) animals die in utero. The DUSP9 gene is on the X chromosome, and this pattern of embryonic lethality is consistent with the selective inactivation of the paternal X chromosome in the extraembryonic tissues of the mouse, suggesting that DUSP9/MKP4 performs an essential function during placental development. Examination of embryos between 8 and 10.5 days postcoitum confirmed that lethality was due to a failure of labyrinth development, and this correlates exactly with the normal expression pattern of DUSP9/MKP-4 in the trophoblast giant cells and labyrinth of the placenta. Finally, when the placental defect was rescued, male null (DUSP9(-/y)) embryos developed to term, appeared normal, and were fertile. Our results indicate that DUSP9/MKP-4 is essential for placental organogenesis but is otherwise dispensable for mammalian embryonic development and highlights the critical role of dual-specificity MAPK phosphatases in the regulation of developmental outcomes in vertebrates.

  20. Sensor Fusion Based on an Integrated Neural Network and Probability Density Function (PDF) Dual Kalman Filter for On-Line Estimation of Vehicle Parameters and States

    PubMed Central

    Vargas-Melendez, Leandro; Boada, Beatriz L.; Boada, Maria Jesus L.; Gauchia, Antonio; Diaz, Vicente

    2017-01-01

    Vehicles with a high center of gravity (COG), such as light trucks and heavy vehicles, are prone to rollover. This kind of accident causes nearly 33% of all deaths from passenger vehicle crashes. Nowadays, these vehicles are incorporating roll stability control (RSC) systems to improve their safety. Most of the RSC systems require the vehicle roll angle as a known input variable to predict the lateral load transfer. The vehicle roll angle can be directly measured by a dual antenna global positioning system (GPS), but it is expensive. For this reason, it is important to estimate the vehicle roll angle from sensors installed onboard in current vehicles. On the other hand, the knowledge of the vehicle’s parameters values is essential to obtain an accurate vehicle response. Some of vehicle parameters cannot be easily obtained and they can vary over time. In this paper, an algorithm for the simultaneous on-line estimation of vehicle’s roll angle and parameters is proposed. This algorithm uses a probability density function (PDF)-based truncation method in combination with a dual Kalman filter (DKF), to guarantee that both vehicle’s states and parameters are within bounds that have a physical meaning, using the information obtained from sensors mounted on vehicles. Experimental results show the effectiveness of the proposed algorithm. PMID:28468252

  1. A novel strategy for dual-channel detection of metallothioneins and mercury based on the conformational switching of functional chimera aptamer.

    PubMed

    Tang, Xian; Wang, Yong-Sheng; Xue, Jin-Hua; Zhou, Bin; Cao, Jin-Xiu; Chen, Si-Han; Li, Ming-Hui; Wang, Xiao-Feng; Zhu, Yu-Feng; Huang, Yan-Qin

    2015-03-25

    A novel strategy for dual-channel detection of metallothioneins (MTs) and Hg(2+) has been proposed. In the absence of Hg(2+), the functional chimera aptamer (FCA) designed can form an intact G-quadruplex with flexibility, which was demonstrated to have peroxidase-like activities upon hemin binding. In the presence of Hg(2+), the formation of T-Hg(2+)-T complex results in the conformational switching of FCA, which lost the peroxidase-like activities and cannot catalyze the oxidation of ABTS by H2O2. Upon addition of MTs in this solution, MTs could interact with Hg(2+) to form a MTs-Hg(2+) complex, leading to the recovery of the G-quadruplex DNAzyme. The color and absorbance of the sensing system were also changed accordingly. In the optimizing condition, ΔA was directly proportional to the concentration ranging from 8.84 nM to 1.0 μM for Hg(2+), and 7.82 nM to 0.462 μM for MTs with the detection limits of 2.65 nM and 2.34 nM, respectively. The proposed dual-channel method avoids the label steps in common methods, and allows direct analysis of the samples without costly instruments, and is reliable, inexpensive and sensitive. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Iridium(iii) phosphorescent complexes with dual stereogenic centers: single crystal, electronic circular dichroism evidence and circularly polarized luminescence properties.

    PubMed

    Li, Tian-Yi; Zheng, You-Xuan; Zhou, Yong-Hui

    2016-12-06

    Iridium complexes with a chiral metal center and chiral carbons, Λ/Δ-(dfppy) 2 Ir(chty-R) and Λ/Δ-(dfppy) 2 Ir(chty-S), were synthesized and characterized. These isomers have the same steady-state photophysical properties, and obvious offsets in ECD spectra highlight both the chiral sources. Each enantiomeric couple shows mirror-image CPL bands with a dissymmetry factor in the order of 10 -3 .

  3. Dual ACE-inhibition and angiotensin II AT1 receptor antagonism with curcumin attenuate maladaptive cardiac repair and improve ventricular systolic function after myocardial infarctionin rat heart.

    PubMed

    Pang, Xue-Fen; Zhang, Li-Hui; Bai, Feng; Wang, Ning-Ping; Ijaz Shah, Ahmed; Garner, Ron; Zhao, Zhi-Qing

    2015-01-05

    Curcumin has been shown to improve cardiac function by reducing degradation of extracellular matrix and inhibiting synthesis of collagen after ischemia. This study tested the hypothesis that attenuation of maladaptive cardiac repair with curcumin is associated with a dual ACE-inhibition and angiotensin II AT1 receptor antagonism after myocardial infarction. Sprague-Dawley rats were subjected to 45min ischemia followed by 7 and 42 days of reperfusion, respectively. Curcumin was fed orally at a dose of 150mg/kg/day only during reperfusion. Relative to the control animals, dietary treatment with curcumin significantly reduced levels of ACE and AT1 receptor protein as determined by Western blot assay, coincident with less locally-expressed ACE and AT1 receptor in myocardium and coronary vessels as identified by immunohistochemistry. Along with this inhibition, curcumin significantly increased protein level of AT2 receptor and its expression compared with the control. As evidenced by less collagen deposition in fibrotic myocardium, curcumin also reduced the extent of collagen-rich scar and increased mass of viable myocardium detected by Masson׳s trichrome staining. Echocardiography showed that the wall thickness of the infarcted anterior septum in the curcumin group was significantly greater than that in the control group. Cardiac contractile function was improved in the curcumin treated animals as measured by fraction shortening and ejection fraction. In cultured cardiac muscle cells, curcumin inhibited oxidant-induced AT1 receptor expression and promoted cell survival. These results suggest that curcumin attenuates maladaptive cardiac repair and enhances cardiac function, primarily mediated by a dual ACE-inhibition and AT1 receptor antagonism after myocardial infarction. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Interfacial Strength and Physical Properties of Functionalized Graphene - Epoxy Nanocomposites

    NASA Technical Reports Server (NTRS)

    Miller, Sandi G.; Heimann, Paula; Scheiman, Daniel; Adamson, Douglas H.; Aksay, Iihan A.; Prud'homme, Robert K.

    2006-01-01

    The toughness and coefficient of thermal expansion of a series of functionalized graphene sheet - epoxy nanocomposites are investigated. Functionalized graphene sheets are produced by splitting graphite oxide into single graphene sheets through a rapid thermal expansion process. These graphene sheets contain approx. 10% oxygen due to the presence of hydroxide, epoxide, and carboxyl functional groups which assist in chemical bond formation with the epoxy matrix. Intrinsic surface functionality is used to graft alkyl amine chains on the graphene sheets, and the addition of excess hardener insures covalent bonding between the epoxide matrix and graphene sheets. Considerable improvement in the epoxy dimensional stability is obtained. An increase in nanocomposite toughness is observed in some cases.

  5. Human Milk: Bioactive Proteins/Peptides and Functional Properties.

    PubMed

    Lönnerdal, Bo

    2016-06-23

    Breastfeeding has been associated with many benefits, both in the short and in the long term. Infants being breastfed generally have less illness and have better cognitive development at 1 year of age than formula-fed infants. Later in life, they have a lower risk of obesity, diabetes and cardiovascular disease. Several components in breast milk may be responsible for these different outcomes, but bioactive proteins/peptides likely play a major role. Some proteins in breast milk are comparatively resistant towards digestion and may therefore exert their functions in the gastrointestinal tract in intact form or as larger fragments. Other milk proteins may be partially digested in the upper small intestine and the resulting peptides may exert functions in the lower small intestine. Lactoferrin, lysozyme and secretory IgA have been found intact in the stool of breastfed infants and are therefore examples of proteins that are resistant against proteolytic degradation in the gut. Together, these proteins serve protective roles against infection and support immune function in the immature infant. α-lactalbumin, β-casein, κ-casein and osteopontin are examples of proteins that are partially digested in the upper small intestine, and the resulting peptides influence functions in the gut. Such functions include stimulation of immune function, mineral and trace element absorption and defense against infection. © 2016 Nestec Ltd., Vevey/S. Karger AG, Basel.

  6. Functional components and medicinal properties of food: a review.

    PubMed

    Abuajah, Christian Izuchukwu; Ogbonna, Augustine Chima; Osuji, Chijioke Maduka

    2015-05-01

    Research has proved a relationship between functional components of food, health and well-being. Thus, functional components of food can be effectively applied in the treatment and prevention of diseases. They act simultaneously at different or identical target sites with the potential to impart physiological benefits and promotion of wellbeing including reducing the risk of cancer, cardiovascular disease, osteoporosis, inflammation, type II diabetes, and other chronic degenerative diseases, lowering of blood cholesterol, neutralization of reactive oxygen species and charged radicals, anticarcinogenic effect, low-glycaemic response, etc. Previously, it was thought that functional ingredients such as non-starchy carbohydrates including soluble and insoluble dietary fibres, fucoidan; antioxidants including polyphenols, carotenoids, tocopherols, tocotrienols, phytosterols, isoflavones, organosulphur compounds; plant sterols and soy phytoestrogens occur only in plant foods (whole grains, fruits, and vegetables) as phytochemicals. However, probiotics, prebiotics, conjugated linolenic acid, long-chain omega-3, -6 and -9-polyunsaturated fatty acids, and bioactive peptides have proved that functional components are equally available in animal products such as milk, fermented milk products and cold-water fish. The way a food is processed affects its functional components. Many processing techniques have been found to lower the concentration of functional components in food. Conversely, other techniques were found to increase them. Hence, in a time when the role of a healthy diet in preventing non-communicable diseases is well accepted, the borderline between food and medicine is becoming very thin.

  7. A Dual Phenotype of Periventricular Nodular Heterotopia and Frontometaphyseal Dysplasia in One Patient Caused by a Single FLNA Mutation Leading to Two Functionally Different Aberrant Transcripts

    PubMed Central

    Zenker, Martin; Rauch, Anita; Winterpacht, Andreas; Tagariello, Andreas; Kraus, Cornelia; Rupprecht, Thomas; Sticht, Heinrich; Reis, André

    2004-01-01

    Two disorders, periventricular nodular heterotopia (PVNH) and a group of skeletal dysplasias belonging to the oto-palato-digital (OPD) spectrum, are caused by FLNA mutations. They are considered mutually exclusive because of the different presumed effects of the respective FLNA gene mutations, leading to loss of function (PVNH) and gain of function (OPD), respectively. We describe here the first patient manifesting PVNH in combination with frontometaphyseal dysplasia, a skeletal dysplasia of the OPD-spectrum. A novel de novo mutation, 7315C→A in exon 45 of the FLNA gene, was identified. It leads to two aberrant transcripts, one full-length transcript with the point mutation causing a substitution of a highly conserved leucine residue (L2439M) and a second shortened transcript lacking 21 bp due to the creation of an ectopic splice donor site in exon 45. We propose that the dual phenotype is caused by two functionally different, aberrant filamin A proteins and therefore represents an exceptional model case of allelic gain-of-function and loss-of-function phenotypes due to a single mutational event. PMID:14988809

  8. Clay-cement suspensions - rheological and functional properties

    NASA Astrophysics Data System (ADS)

    Wojcik, L.; Izak, P.; Mastalska-Poplawska, J.; Gajek, M.

    2017-01-01

    The piping erosion in soil is highly unexpected in civil engineering. Elimination of such damages is difficult, expensive and time-consuming. One of the possibility is the grouting method. This method is still developed into direction of process automation as well as other useful properties of suspensions. Main way of modernization of the grouting method is connected it with rheology of injection and eventuality of fitting them to specific problems conditions. Very popular and useful became binders based on modified clays (clay-cement suspensions). Important principle of efficiency of the grouting method is using of time-dependent pseudothixotropic properties of the clay-cement suspensions. The pseudo-rheounstability aspect of the suspensions properties should be dedicated and fitted to dynamic changes of soil conditions destructions. Whole process of the modification of the suspension rheology is stimulated by the specific agents. This article contains a description of practical aspects of the rheological parameters managing of the clay-cement suspensions, dedicated to the building damages, hydrotechnic constructions etc.

  9. Dual-readout calorimetry

    NASA Astrophysics Data System (ADS)

    Lee, Sehwook; Livan, Michele; Wigmans, Richard

    2018-04-01

    In the past 20 years, dual-readout calorimetry has emerged as a technique for measuring the properties of high-energy hadrons and hadron jets that offers considerable advantages compared with the instruments that are currently used for this purpose in experiments at the high-energy frontier. The status of this experimental technique and the challenges faced for its further development are reviewed.

  10. Interfacial effect on the structural and optical properties of pure SnO2 and dual shells (ZnO; SiO2) coated SnO2 core-shell nanospheres for optoelectronic applications

    NASA Astrophysics Data System (ADS)

    Selvi, N.; Sankar, S.; Dinakaran, K.

    2014-12-01

    Nanocrystallites of SnO2 core and dual shells (ZnO, SiO2) coated SnO2 core-shell nanospheres were successfully synthesized by co-precipitation method. The as prepared and annealed samples were characterized by X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), High resolution transmission electron microscopy (HRTEM) and UV-Vis analysis. XRD pattern confirms the obtained SnO2 core with tetragonal rutile crystalline structure and the shell ZnO with hexagonal structure. FTIR result shows the functional groups present in the samples. The spherical morphology and the formation of the core-shell structures have been confirmed by HRTEM measurements. The UV-Vis showed that band gap is red shifted for as-prepared and the shells coated core-shell samples. From this investigation it can be concluded that the surface modification with different metal and insulating oxides strongly influences the optical properties of the core-shell materials which enhance their potential applications towards optical devices fabrication.

  11. Elastic properties of protein functionalized nanoporous polymer films

    DOE PAGES

    Charles T. Black; Wang, Haoyu; Akcora, Pinar

    2015-12-16

    Retaining the conformational structure and bioactivity of immobilized proteins is important for biosensor designs and drug delivery systems. Confined environments often lead to changes in conformation and functions of proteins. In this study, lysozyme is chemically tethered into nanopores of polystyrene thin films, and submicron pores in poly(methyl methacrylate) films are functionalized with streptavidin. Nanoindentation experiments show that stiffness of streptavidin increases with decreasing submicron pore sizes. Lysozymes in polystyrene nanopores are found to behave stiffer than the submicron pore sizes and still retain their specific bioactivity relative to the proteins on flat surfaces. Lastly, our results show that proteinmore » functionalized ordered nanoporous polystyrene/poly(methyl methacrylate) films present heterogeneous elasticity and can be used to study interactions between free proteins and designed surfaces.« less

  12. Memory functions reveal structural properties of gene regulatory networks

    PubMed Central

    Perez-Carrasco, Ruben

    2018-01-01

    Gene regulatory networks (GRNs) control cellular function and decision making during tissue development and homeostasis. Mathematical tools based on dynamical systems theory are often used to model these networks, but the size and complexity of these models mean that their behaviour is not always intuitive and the underlying mechanisms can be difficult to decipher. For this reason, methods that simplify and aid exploration of complex networks are necessary. To this end we develop a broadly applicable form of the Zwanzig-Mori projection. By first converting a thermodynamic state ensemble model of gene regulation into mass action reactions we derive a general method that produces a set of time evolution equations for a subset of components of a network. The influence of the rest of the network, the bulk, is captured by memory functions that describe how the subnetwork reacts to its own past state via components in the bulk. These memory functions provide probes of near-steady state dynamics, revealing information not easily accessible otherwise. We illustrate the method on a simple cross-repressive transcriptional motif to show that memory functions not only simplify the analysis of the subnetwork but also have a natural interpretation. We then apply the approach to a GRN from the vertebrate neural tube, a well characterised developmental transcriptional network composed of four interacting transcription factors. The memory functions reveal the function of specific links within the neural tube network and identify features of the regulatory structure that specifically increase the robustness of the network to initial conditions. Taken together, the study provides evidence that Zwanzig-Mori projections offer powerful and effective tools for simplifying and exploring the behaviour of GRNs. PMID:29470492

  13. Statistical properties and correlation functions for drift waves

    NASA Technical Reports Server (NTRS)

    Horton, W.

    1986-01-01

    The dissipative one-field drift wave equation is solved using the pseudospectral method to generate steady-state fluctuations. The fluctuations are analyzed in terms of space-time correlation functions and modal probability distributions. Nearly Gaussian statistics and exponential decay of the two-time correlation functions occur in the presence of electron dissipation, while in the absence of electron dissipation long-lived vortical structures occur. Formulas from renormalized, Markovianized statistical turbulence theory are given in a local approximation to interpret the dissipative turbulence.

  14. Enhancement of photocurrent extraction and electron injection in dual-functional CH3NH3PbBr3 perovskite-based optoelectronic devices via interfacial engineering

    NASA Astrophysics Data System (ADS)

    Tsai, Chia-Lung; Lu, Yi-Chen; Hsiung Chang, Sheng

    2018-07-01

    Photocurrent extraction and electron injection in CH3NH3PbBr3 (MAPbBr3) perovskite-based optoelectronic devices are both significantly increased by improving the contact at the PCBM/MAPbBr3 interface with an extended solvent annealing (ESA) process. Photoluminescence quenching and x-ray diffraction experiments show that the ESA not only improves the contact at the PCBM/MAPbBr3 interface but also increases the crystallinity of the MAPbBr3 thin films. The optimized dual-functional PCBM-MAPbBr3 heterojunction based optoelectronic device has a high power conversion efficiency of 4.08% and a bright visible luminescence of 1509 cd m‑2. In addition, the modulation speed of the MAPbBr3 based light-emitting diodes is larger than 14 MHz, which indicates that the defect density in the MAPbBr3 thin film can be effectively reduced by using the ESA process.

  15. An all-solid-state perovskite-sensitized solar cell based on the dual function polyaniline as the sensitizer and p-type hole-transporting material

    NASA Astrophysics Data System (ADS)

    Xiao, Yaoming; Han, Gaoyi; Chang, Yunzhen; Zhou, Haihan; Li, Miaoyu; Li, Yanping

    2014-12-01

    High performance dual function of polyaniline (PANI) with brachyplast structure is synthesized by using a two-step cyclic voltammetry (CV) approach onto the fluorinated tin oxide (FTO) glass substrate, which acts as the sensitizer and p-type hole-transporting material (p-HTM) for the all-solid-state perovskite-sensitized solar cell (ass-PSSC) due to its π-π* transition and the localized polaron. The ass-PSSC based on the PANI delivers a photovoltaic conversion efficiency of 7.34%, and reduces from 7.34% to 6.71% after 1000 h, thereby 91.42% of the energy conversion efficiency is kept, indicating the device has a good long-term stability.

  16. Enhancement of photocurrent extraction and electron injection in dual-functional CH3NH3PbBr3 perovskite-based optoelectronic devices via interfacial engineering.

    PubMed

    Tsai, Chia-Lung; Lu, Yi-Chen; Chang, Sheng Hsiung

    2018-07-06

    Photocurrent extraction and electron injection in CH 3 NH 3 PbBr 3 (MAPbBr 3 ) perovskite-based optoelectronic devices are both significantly increased by improving the contact at the PCBM/MAPbBr 3 interface with an extended solvent annealing (ESA) process. Photoluminescence quenching and x-ray diffraction experiments show that the ESA not only improves the contact at the PCBM/MAPbBr 3 interface but also increases the crystallinity of the MAPbBr 3 thin films. The optimized dual-functional PCBM-MAPbBr 3 heterojunction based optoelectronic device has a high power conversion efficiency of 4.08% and a bright visible luminescence of 1509 cd m -2 . In addition, the modulation speed of the MAPbBr 3 based light-emitting diodes is larger than 14 MHz, which indicates that the defect density in the MAPbBr 3 thin film can be effectively reduced by using the ESA process.

  17. The Effect of Chemical Functionalization on Mechanical Properties of Nanotube/Polymer Composites

    NASA Technical Reports Server (NTRS)

    Odegard, G. M.; Frankland, S. J. V.; Gates, T. S.

    2003-01-01

    The effects of the chemical functionalization of a carbon nanotube embedded in a nanotube/polyethylene composite on the bulk elastic properties are presented. Constitutive equations are established for both functionalized and non-functionalized nanotube composites systems by using an equivalent-continuum modeling technique. The elastic properties of both composites systems are predicted for various nanotube lengths, volume fractions, and orientations. The results indicate that for the specific composite material considered in this study, most of the elastic stiffness constants of the functionalized composite are either less than or equal to those of the non-functionalized composite.

  18. Fabrication of Concentrated Fish Oil Emulsions Using Dual-Channel Microfluidization: Impact of Droplet Concentration on Physical Properties and Lipid Oxidation.

    PubMed

    Liu, Fuguo; Zhu, Zhenbao; Ma, Cuicui; Luo, Xiang; Bai, Long; Decker, Eric Andrew; Gao, Yanxiang; McClements, David Julian

    2016-12-21

    Chemically unstable lipophilic bioactives, such as polyunsaturated lipids, often have to be encapsulated in emulsion-based delivery systems before they can be incorporated into foods, supplements, and pharmaceuticals. The objective of this study was to develop highly concentrated emulsion-based fish oil delivery systems using natural emulsifiers. Fish oil-in-water emulsions were fabricated using a highly efficient dual-channel high-pressure microfluidizer. The impact of oil concentration on the formation, physical properties, and oxidative stability of fish oil emulsions prepared using two natural emulsifiers (quillaja saponins and rhamnolipids) and one synthetic emulsifier (Tween-80) was examined. The mean droplet size, polydispersity, and apparent viscosity of the fish oil emulsions increased with increasing oil content. However, physically stable emulsions with high fish oil levels (30 or 40 wt %) could be produced using all three emulsifiers, with rhamnolipids giving the smallest droplet size (d < 160 nm). The stability of the emulsions to lipid oxidation increased as the oil content increased. The oxidative stability of the emulsions also depended on the nature of the emulsifier coating the lipid droplets, with the oxidative stability decreasing in the following order: rhamnolipids > saponins ≈ Tween-80. These results suggest that rhamnolipids may be particularly effective at producing emulsions containing high concentrations of ω-3 polyunsaturated fatty acids-rich fish oil.

  19. Pterostilbene-O-acetamidoalkylbenzylamines derivatives as novel dual inhibitors of cholinesterase with anti-β-amyloid aggregation and antioxidant properties for the treatment of Alzheimer's disease.

    PubMed

    Li, Yuxing; Qiang, Xiaoming; Li, Yan; Yang, Xia; Luo, Li; Xiao, Ganyuan; Cao, Zhongcheng; Tan, Zhenghuai; Deng, Yong

    2016-04-15

    A series of pterostilbene-O-acetamidoalkylbenzylamines were designed, synthesized and evaluated as dual inhibitors of AChE and BuChE. To further explore the multifunctional properties of the new derivatives, their antioxidant activities and inhibitory effects on self-induced Aβ1-42 aggregation and HuAChE-induced Aβ1-40 aggregation were also tested. The results showed that most of these compounds could effectively inhibit AChE and BuChE. Particularly, compound 21d exhibited the best AChE inhibitory activity (IC50=0.06 μM) and good inhibition of BuChE (IC50=28.04 μM). Both the inhibition kinetic analysis and molecular modeling study revealed that these compounds showed mixed-type inhibition, binding simultaneously to the CAS and PAS of AChE. In addition to cholinesterase inhibitory activities, these compounds showed different levels of antioxidant activity. However, the inhibitory activities against self-induced and HuAChE-induced Aβ aggregation of these new derivatives were unsatisfied. Taking into account the results of the biological evaluation, further modifications will be designed in order to increase the potency on the different targets. The results displayed in this Letter can be a new starting point for further development of multifunctional agents for Alzheimer's disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Fabrication of flower-like micro/nano dual scale structured copper oxide surfaces: Optimization of self-cleaning properties via Taguchi design

    NASA Astrophysics Data System (ADS)

    Moosavi, Saeideh Sadat; Norouzbeigi, Reza; Velayi, Elmira

    2017-11-01

    In the present work, copper oxide superhydrophobic surface is fabricated on a copper foil via the chemical bath deposition (CBD) method. The effects of some influential factors such as initial concentrations of Cu (II) ions and the surface energy modifier, solution pH, reaction and modification steps time on the wettability property of copper oxide surface were evaluated using Taguchi L16 experimental design. Results showed that the initial concentration of Cu (II) has the most significant impact on the water contact angle and wettability characteristics. The XRD, SEM, AFM and FTIR analyses were used to characterize the copper oxide surfaces. The Water contact angle (WCA) and contact angle hysteresis (CAH) were also measured. The SEM results indicated the formation of a flower-like micro/nano dual-scale structure of copper oxide on the substrate. This structure composed of numerous nano-petals with a thickness of about 50 nm. As a result, a copper oxide hierarchical surface with WCA of 168.4°± 3.5° and CAH of 2.73° exhibited the best superhydrophobicity under proposed optimum condition. This result has been obtained just by 10 min hydrolysis reaction. Besides, this surface showed a good stability under acidic and saline conditions.

  1. Estimating Age Distributions of Base Flow in Watersheds Underlain by Single and Dual Porosity Formations Using Groundwater Transport Simulation and Weighted Weibull Functions

    NASA Astrophysics Data System (ADS)

    Sanford, W. E.

    2015-12-01

    Age distributions of base flow to streams are important to estimate for predicting the timing of water-quality responses to changes in distributed inputs of nutrients or pollutants at the land surface. Simple models of shallow aquifers will predict exponential age distributions, but more realistic 3-D stream-aquifer geometries will cause deviations from an exponential curve. In addition, in fractured rock terrains the dual nature of the effective and total porosity of the system complicates the age distribution further. In this study shallow groundwater flow and advective transport were simulated in two regions in the Eastern United States—the Delmarva Peninsula and the upper Potomac River basin. The former is underlain by layers of unconsolidated sediment, while the latter consists of folded and fractured sedimentary rocks. Transport of groundwater to streams was simulated using the USGS code MODPATH within 175 and 275 watersheds, respectively. For the fractured rock terrain, calculations were also performed along flow pathlines to account for exchange between mobile and immobile flow zones. Porosities at both sites were calibrated using environmental tracer data (3H, 3He, CFCs and SF6) in wells and springs, and with a 30-year tritium record from the Potomac River. Carbonate and siliciclastic rocks were calibrated to have mobile porosity values of one and six percent, and immobile porosity values of 18 and 12 percent, respectively. The age distributions were fitted to Weibull functions. Whereas an exponential function has one parameter that controls the median age of the distribution, a Weibull function has an extra parameter that controls the slope of the curve. A weighted Weibull function was also developed that potentially allows for four parameters, two that control the median age and two that control the slope, one of each weighted toward early or late arrival times. For both systems the two-parameter Weibull function nearly always produced a substantially

  2. Effects of cognitive-motor dual-task training combined with auditory motor synchronization training on cognitive functioning in individuals with chronic stroke: A pilot randomized controlled trial.

    PubMed

    Park, Myoung-Ok; Lee, Sang-Heon

    2018-06-01

    Preservation and enhancement of cognitive function are essential for the restoration of functional abilities and independence following stroke. While cognitive-motor dual-task training (CMDT) has been utilized in rehabilitation settings, many patients with stroke experience impairments in cognitive function that can interfere with dual-task performance. In the present study, we investigated the effects of CMDT combined with auditory motor synchronization training (AMST) utilizing rhythmic cues on cognitive function in patients with stroke. The present randomized controlled trial was conducted at a single rehabilitation hospital. Thirty patients with chronic stroke were randomly divided an experimental group (n = 15) and a control group (n = 15). The experimental group received 3 CMDT + AMST sessions per week for 6 weeks, whereas the control group received CMDT only 3 times per week for 6 weeks. Changes in cognitive function were evaluated using the trail making test (TMT), digit span test (DST), and stroop test (ST). Significant differences in TMT-A and B (P = .001, P = .001), DST-forward (P = .001, P = .001), DST-backward (P = .000, P = .001), ST-word (P = .001, P = .001), and ST-color (P = .002, P = .001) scores were observed in both the control and experimental groups, respectively. Significant differences in TMT-A (P = .001), DST-forward (P = .027), DST-backward (P = .002), and ST-word (P = .025) scores were observed between the 2 groups. Performance speed on the TMT-A was faster in the CMDT + AMST group than in the CMDT group. Moreover, DST-forward and DST-backward scores were higher in the CMDT + AMST group than in the CDMT group. Although ST-color results were similar in the 2 groups, ST-word scores were higher in the CMDT + AMST group than in the CMDT group. This finding indicates that the combined therapy CMDT and AMST can be used to increase attention, memory, and executive

  3. Chemical Modifications that Affect Nutritional and Functional Properties of Proteins.

    ERIC Educational Resources Information Center

    Richardson, T.; Kester, J. J.

    1984-01-01

    Discusses chemical alterations of selected amino acids resulting from environmental effects (photooxidations, pH extremes, thermally induced effects). Also dicusses use of intentional chemical derivatizations of various functional groups in amino acid residue side chains and how recombinant DNA techniques might be useful in structure/function…

  4. Properties of rice bran oil-derived functional ingredients

    USDA-ARS?s Scientific Manuscript database

    Lipid ingredients that demonstrate high stability and positive health profiles without the use of trans-fats are needed in the food supply. Rice bran oil can be fractionated at low temperatures to create a series of spreads that show promise as functional ingredients. A rice bran oil-derived spread ...

  5. A Construction of Boolean Functions with Good Cryptographic Properties

    DTIC Science & Technology

    2014-01-01

    be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT...2008, LNCS 5350, Springer–Verlag, 2008, pp. 425–440. [10] C. Carlet and K. Feng, “An Infinite Class of Balanced Vectorial Boolean Functions with Optimum

  6. Cryptographic Properties of the Hidden Weighted Bit Function

    DTIC Science & Technology

    2013-12-23

    valid OMB control number. 1. REPORT DATE 23 DEC 2013 2. REPORT TYPE 3. DATES COVERED 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE...K. Feng, An Infinite Class of Balanced Vectorial Boolean Functions with Optimum Algebraic Immunity and Good Nonlinearity, in: IWCC 2009, In: LNCS

  7. Biological properties of extracellular vesicles and their physiological functions

    PubMed Central

    Yáñez-Mó, María; Siljander, Pia R.-M.; Andreu, Zoraida; Zavec, Apolonija Bedina; Borràs, Francesc E.; Buzas, Edit I.; Buzas, Krisztina; Casal, Enriqueta; Cappello, Francesco; Carvalho, Joana; Colás, Eva; Silva, Anabela Cordeiro-da; Fais, Stefano; Falcon-Perez, Juan M.; Ghobrial, Irene M.; Giebel, Bernd; Gimona, Mario; Graner, Michael; Gursel, Ihsan; Gursel, Mayda; Heegaard, Niels H. H.; Hendrix, An; Kierulf, Peter; Kokubun, Katsutoshi; Kosanovic, Maja; Kralj-Iglic, Veronika; Krämer-Albers, Eva-Maria; Laitinen, Saara; Lässer, Cecilia; Lener, Thomas; Ligeti, Erzsébet; Linē, Aija; Lipps, Georg; Llorente, Alicia; Lötvall, Jan; Manček-Keber, Mateja; Marcilla, Antonio; Mittelbrunn, Maria; Nazarenko, Irina; Hoen, Esther N.M. Nolte-‘t; Nyman, Tuula A.; O'Driscoll, Lorraine; Olivan, Mireia; Oliveira, Carla; Pállinger, Éva; del Portillo, Hernando A.; Reventós, Jaume; Rigau, Marina; Rohde, Eva; Sammar, Marei; Sánchez-Madrid, Francisco; Santarém, N.; Schallmoser, Katharina; Ostenfeld, Marie Stampe; Stoorvogel, Willem; Stukelj, Roman; Van der Grein, Susanne G.; Vasconcelos, M. Helena; Wauben, Marca H. M.; De Wever, Olivier

    2015-01-01

    In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells. While intensive investigation has targeted the role of EVs in different pathological processes, for example, in cancer and autoimmune diseases, the EV-mediated maintenance of homeostasis and the regulation of physiological functions have remained less explored. Here, we provide a comprehensive overview of the current understanding of the physiological roles of EVs, which has been written by crowd-sourcing, drawing on the unique EV expertise of academia-based scientists, clinicians and industry based in 27 European countries, the United States and Australia. This review is intended to be of relevance to both researchers already working on EV biology and to newcomers who will encounter this universal cell biological system. Therefore, here we address the molecular contents and functions of EVs in various tissues and body fluids from cell systems to organs. We also review the physiological mechanisms of EVs in bacteria, lower eukaryotes and plants to highlight the functional uniformity of this emerging communication system. PMID:25979354

  8. Biological properties of extracellular vesicles and their physiological functions.

    PubMed

    Yáñez-Mó, María; Siljander, Pia R-M; Andreu, Zoraida; Zavec, Apolonija Bedina; Borràs, Francesc E; Buzas, Edit I; Buzas, Krisztina; Casal, Enriqueta; Cappello, Francesco; Carvalho, Joana; Colás, Eva; Cordeiro-da Silva, Anabela; Fais, Stefano; Falcon-Perez, Juan M; Ghobrial, Irene M; Giebel, Bernd; Gimona, Mario; Graner, Michael; Gursel, Ihsan; Gursel, Mayda; Heegaard, Niels H H; Hendrix, An; Kierulf, Peter; Kokubun, Katsutoshi; Kosanovic, Maja; Kralj-Iglic, Veronika; Krämer-Albers, Eva-Maria; Laitinen, Saara; Lässer, Cecilia; Lener, Thomas; Ligeti, Erzsébet; Linē, Aija; Lipps, Georg; Llorente, Alicia; Lötvall, Jan; Manček-Keber, Mateja; Marcilla, Antonio; Mittelbrunn, Maria; Nazarenko, Irina; Nolte-'t Hoen, Esther N M; Nyman, Tuula A; O'Driscoll, Lorraine; Olivan, Mireia; Oliveira, Carla; Pállinger, Éva; Del Portillo, Hernando A; Reventós, Jaume; Rigau, Marina; Rohde, Eva; Sammar, Marei; Sánchez-Madrid, Francisco; Santarém, N; Schallmoser, Katharina; Ostenfeld, Marie Stampe; Stoorvogel, Willem; Stukelj, Roman; Van der Grein, Susanne G; Vasconcelos, M Helena; Wauben, Marca H M; De Wever, Olivier

    2015-01-01

    In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells. While intensive investigation has targeted the role of EVs in different pathological processes, for example, in cancer and autoimmune diseases, the EV-mediated maintenance of homeostasis and the regulation of physiological functions have remained less explored. Here, we provide a comprehensive overview of the current understanding of the physiological roles of EVs, which has been written by crowd-sourcing, drawing on the unique EV expertise of academia-based scientists, clinicians and industry based in 27 European countries, the United States and Australia. This review is intended to be of relevance to both researchers already working on EV biology and to newcomers who will encounter this universal cell biological system. Therefore, here we address the molecular contents and functions of EVs in various tissues and body fluids from cell systems to organs. We also review the physiological mechanisms of EVs in bacteria, lower eukaryotes and plants to highlight the functional uniformity of this emerging communication system.

  9. Evaluation of two dual-functional primers and a tribochemical surface modification system applied to the bonding of an indirect composite resin to metals.

    PubMed

    Yanagida, Hiroaki; Tanoue, Naomi; Ide, Takako; Matsumura, Hideo

    2009-07-01

    We evaluated the effects of two dual-functional primers and a tribochemical surface modification system on the bond strength between an indirect composite resin and gold alloy or titanium. Disk specimens (diameter, 10 mm; thickness, 2.5 mm) were cast from type 4 gold alloy and commercially pure titanium. The specimens were wetground to a final surface finish using 600-grit silicone carbide paper. The specimens were then air-dried and treated using the following four bonding systems: (1) air-abrasion with 50-70 mum alumina, (2) system 1 + alloy primer, (3) system 1 + metal link primer, and (4) tribochemical silica/silane coating (Rocatec). A light-polymerizing indirect composite resin (Ceramage) was applied to each metal specimen and polymerized according to the manufacturer's specifications. Shear bond strengths (MPa) were determined both before and after thermocycling (4 degrees C and 60 degrees C for 1 min each for 20 000 cycles). The values were compared using analysis of variance, post hoc Scheffe tests, and Mann-Whitney U tests (alpha = 0.05). The strengths decreased after thermocycling for all combinations. For both gold alloy and titanium, the bond strength with air-abrasion only was statistically lower than that with the other three modification methods after thermocycling. Titanium exhibited a significantly higher value (13.4 MPa) than gold alloy (10.5 MPa) with the air. abrasion and alloy primer system. Treatment with the tribochemical system or air abrasion followed by treatment with dual-functional priming agents was found to be effective for enhancement of the bonding between the indirect composite and gold alloy or titanium.

  10. A novel dual-functional biosensor for fluorometric detection of inorganic pyrophosphate and pyrophosphatase activity based on globulin stabilized gold nanoclusters.

    PubMed

    Xu, Shenghao; Feng, Xiuying; Gao, Teng; Wang, Ruizhi; Mao, Yaning; Lin, Jiehua; Yu, Xijuan; Luo, Xiliang

    2017-03-15

    A novel ultrasensitive dual-functional biosensor for highly sensitive detection of inorganic pyrophosphate (PPi) and pyrophosphatase (PPase) activity was developed based on the fluorescent variation of globulin protected gold nanoclusters (Glo@Au NCs) with the assistance of Cu 2+ . Glo@Au NCs and PPi were used as the fluorescent indicator and substrate for PPase activity evaluation, respectively. In the presence of Cu 2+ , the fluorescence of the Glo@Au NCs will be quenched owing to the formation of Cu 2+ -Glo@Au NCs complex, while PPi can restore the fluorescence of the Cu 2+ -Glo@Au NCs complex because of its higher binding affinity with Cu 2+ . As PPase can catalyze the hydrolysis of PPi, it will lead to the release of Cu 2+ and re-quench the fluorescence of the Glo@Au NCs. Based on this mechanism, quantitative evaluation of the PPi and PPase activity can be achieved ranging from 0.05 μM to 218.125 μM for PPi and from 0.1 to 8 mU for PPase, with detection limits of 0.02 μM and 0.04 mU, respectively, which is much lower than that of other PPi and PPase assay methods. More importantly, this ultrasensitive dual-functional biosensor can also be successfully applied to evaluate the PPase activity in human serum, showing great promise for practical diagnostic applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Preparation and Properties of Nanocomposites Prepared From Shortened, Functionalized Single-Walled Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

    Smith, J. G., Jr.; Delozier, D. M.; Watson, K. A.; Connell, J. W.; Yu, Aiping; Haddon, R. C.; Bekyarova, E.

    2006-01-01

    As part of a continuing materials development activity, low color space environmentally stable polymeric materials that possess sufficient electrical conductivity for electrostatic charge dissipation (ESD) have been investigated. One method of incorporating sufficient electrical conductivity for ESD without detrimental effects on other polymer properties of interest (i.e., optical and thermo-optical) is through the incorporation of single-walled carbon nanotubes (SWNTs). However, SWNTs are difficult to fully disperse in the polymer matrix. One means of improving dispersion is by shortening and functionalizing SWNTs. While this improves dispersion, other properties (i.e., electrical) of the SWNTs can be affected which can in turn alter the final nanocomposite properties. Additionally, functionalization of the polymer matrix can also influence nanocomposite properties obtained from shortened, functionalized SWNTs. The preparation and characterization of nanocomposites fabricated from a polyimide, both functionalized and unfunctionalized, and shortened, functionalized SWNTs will be presented.

  12. Excited State Charge Transfer reaction with dual emission from 5-(4-dimethylamino-phenyl)-penta-2,4-dienenitrile: Spectral measurement and theoretical density functional theory calculation

    NASA Astrophysics Da