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Sample records for alanine-rich c-kinase substrate

  1. Kinetics of interaction of the myristoylated alanine-rich C kinase substrate, membranes, and calmodulin.

    Science.gov (United States)

    Arbuzova, A; Wang, J; Murray, D; Jacob, J; Cafiso, D S; McLaughlin, S

    1997-10-24

    Membrane binding of the myristoylated alanine-rich C kinase substrate (MARCKS) requires both its myristate chain and basic "effector" region. Previous studies with a peptide corresponding to the effector region, MARCKS-(151-175), showed that the 13 basic residues interact electrostatically with acidic lipids and that the 5 hydrophobic phenylalanine residues penetrate the polar head group region of the bilayer. Here we describe the kinetics of the membrane binding of fluorescent (acrylodan-labeled) peptides measured with a stopped-flow technique. Even though the peptide penetrates the polar head group region, the association of MARCKS-(151-175) with membranes is extremely rapid; association occurs with a diffusion-limited association rate constant. For example, kon = 10(11) M-1 s-1 for the peptide binding to 100-nm diameter phospholipid vesicles. As expected theoretically, kon is independent of factors that affect the molar partition coefficient, such as the mole fraction of acidic lipid in the vesicle and the salt concentration. The dissociation rate constant (koff) is approximately 10 s-1 (lifetime = 0.1 s) for vesicles with 10% acidic lipid in 100 mM KCl. Ca2+-calmodulin (Ca2+.CaM) decreases markedly the lifetime of the peptide on vesicles, e.g. from 0.1 to 0.01 s in the presence of 5 micrM Ca2+.CaM. Our results suggest that Ca2+.CaM collides with the membrane-bound MARCKS-(151-175) peptide and pulls the peptide off rapidly. We discuss the biological implications of this switch mechanism, speculating that an increase in the level of Ca2+-calmodulin could rapidly release phosphatidylinositol 4, 5-bisphosphate that previous work has suggested is sequestered in lateral domains formed by MARCKS and MARCKS-(151-175).

  2. Involvement of myristoylated alanine-rich C kinase substrate phosphorylation and translocation in cholecystokinin-induced amylase release in rat pancreatic acini.

    Science.gov (United States)

    Satoh, Keitaro; Narita, Takanori; Katsumata-Kato, Osamu; Sugiya, Hiroshi; Seo, Yoshiteru

    2016-03-15

    Cholecystokinin (CCK) is a gastrointestinal hormone that induces exocytotic amylase release in pancreatic acinar cells. The activation of protein kinase C (PKC) is involved in the CCK-induced pancreatic amylase release. Myristoylated alanine-rich C kinase substrate (MARCKS) is a ubiquitously expressed substrate of PKC. MARCKS has been implicated in membrane trafficking in several cell types. The phosphorylation of MARCKS by PKC results in the translocation of MARCKS from the membrane to the cytosol. Here, we studied the involvement of MARCKS in the CCK-induced amylase release in rat pancreatic acini. Employing Western blotting, we detected MARCKS protein in the rat pancreatic acini. CCK induced MARCKS phosphorylation. A PKC-δ inhibitor, rottlerin, inhibited the CCK-induced MARCKS phosphorylation and amylase release. In the translocation assay, we also observed CCK-induced PKC-δ activation. An immunohistochemistry study showed that CCK induced MARCKS translocation from the membrane to the cytosol. When acini were lysed by a detergent, Triton X-100, CCK partially induced displacement of the MARCKS from the GM1a-rich detergent-resistant membrane fractions (DRMs) in which Syntaxin2 is distributed. A MARCKS-related peptide inhibited the CCK-induced amylase release. These findings suggest that MARCKS phosphorylation by PKC-δ and then MARCKS translocation from the GM1a-rich DRMs to the cytosol are involved in the CCK-induced amylase release in pancreatic acinar cells.

  3. Ste20-related proline/alanine-rich kinase: A novel regulator of intestinal inflammation

    Institute of Scientific and Technical Information of China (English)

    Yutao Yan; Didier Merlin

    2008-01-01

    Recently, inflammatory bowel disease (IBD) has been the subject of considerable research, with increasing attention being paid to the loss of intestinal epithelial cell barrier function as a mechanism of pathogenesis. Ste20-related proline/alanine-rich kinase (SPAK) is involved in regulating barrier function. SPAK is known to interact with inflammation-related kinases (such as p38, JNK, NKCC1, PKCθ, WNK and MLCK), and with transcription factor AP-1, resulting in diverse biological phenomena, including cell differentiation, cell transformation and proliferation, cytoskeleton rearrangement, and regulation of chloride transport. This review examines the involvement of Ste20-like kinases and downstream mitogen-activated protein kinases (MAPKs) pathways in the pathogenesis and control of intestinal inflammation. The primary focus will be on the molecular features of intestinal inflammation, with an emphasis on the interaction between SPAK and other molecules, and the effect of these interactions on homeostatic maintenance, cell volume regulation and increased cell permeability in intestinal inflammation.

  4. Structural and Functional Variation within the Alanine-Rich Repetitive Domain of Streptococcal Antigen I/II

    OpenAIRE

    Demuth, Donald R; Irvine, Douglas C.

    2002-01-01

    Members of the antigen I/II family of cell surface proteins are highly conserved, multifunctional adhesins that mediate interactions of oral streptococci with other oral bacteria, with cell matrix proteins (e.g., type I collagen), and with salivary glycoproteins, e.g., gp340. The interaction of gp340 (formerly designated salivary agglutinin) with Streptococcus mutans requires an alanine-rich repetitive domain (A region) of antigen I/II that is highly conserved in all members of this family of...

  5. Perspective of future drugs targeting sterile 20/SPS1-related proline/alanine-rich kinase for blood pressure control

    Institute of Scientific and Technical Information of China (English)

    Gen-Min; Lin; Pang-Yen; Liu; Ching-Fen; Wu; Wen-Been; Wang; Chih-Lu; Han

    2015-01-01

    According to a genome-wide association study,intronic SNPs within the human sterile 20/SPS1-related proline/alanine-rich kinase(SPAK) gene was linked to 20% of the general population and may be associated with elevated blood pressure. As cell volume changes,mammalian SPAK kinases respond to phosphorylate and regulate cation-coupled chloride co-transporter activity. To our knowledge,phosphorylation of upstream with-no-lysine(K)(WNK) kinases would activate SPAK kinases. The activation of WNK-OSR1/SPAK cascade on the kidneys and aortic tissue is related to the development of hypertension. Several regulators of the WNK pathway such as the Kelch kinase protein 3-Cullin 3 E3 ligase,hyperinsulinemia,and low potassium intake to mediate hypertension have been identified. In addition,the SPAK kinases may affect the action of renin-angiotensin-aldosterone system on blood pressure as well. In 2010,two SPAK knock-in and knock-out mouse models have clarified the pathogenesis of lowering blood pressure by influencing the receptors on the kidneys and aortic smooth muscle. More recently,two novel SPAK inhibitors for mice,Stock 1S-14279 and Closantel were discovered in 2014. Targeting of SPAK seems to be promising for future antihypertensive therapy. Therefore we raised some viewpoints for the issue for the antihypertensive therapy on the SPAK(gene or kinase).

  6. Dioxin modulates expression of receptor for activated C kinase (RACK-1) in developing neurons

    Energy Technology Data Exchange (ETDEWEB)

    Yang, J.H.; Kim, S.Y.; Lee, H.G.; Kim, M.Y.; Lee, J.H.; Chae, W.G. [Catholic Univ. of Daegu, Dept. of Pharmacology/Toxicology, Daegu (Korea)

    2004-09-15

    TCDD is sensitive to the central nerve system of the developing brain. The TCDD-induced neurodevelopmental deficits include the cognitive disability and motor dysfunction. While TCDD may lead to neurodevelopmental and neurobehavioral deficit, it is not known which molecular substances are intracellular targets for TCDD. Since TCDD accumulates in brain and the brain contains the Ah receptor, it is possible that TCDD may act at the target site such as cerebellum, which is responsible for cognitive abilities and motor function. A recent in vitro studies using cerebellar granule cells demonstrated a translocation of PKC-{alpha} and {epsilon} following the TCDD or PCB exposure. One of the most pivotal second messenger molecules involved in neuronal function and development is protein kinase C (PKC). PKC signaling pathways have been implicated as an important factor in learning and memory processes. PKC signaling events are optimized by the adaptor proteins, which organize PKCs near their selective substrates and away from others. RACK-1(receptor for activated C-kinase) is one of adaptor proteins that anchor the activated PKC at the site of translocation 6. RACKs bind PKC only in the presence of PKC activators. RACKs are 30- and 36-kDa proteins located in cytoskeletal compartment and play a key role in PKC activation and in membrane amchoring. Since different PKC isoforms translocate to distinct subcellular sites on activation, it is suggested that isoform-specific RACK may be present. Activation of certain PKC isoforms (PKC-a and {beta}II) is preferentially associated with RACK-1. While TCDD modulates PKC signaling pathway, role of RACK-1 on TCDD-mediated signaling pathway is not known. To identify the intracellular target for TCDD and understand a mechanism of signaling pathway in the developing brain, the present study attempted to analyze effects of RACK-1 in the cerebellar granule cells following TCDD exposure.

  7. Protein receptor for activated C kinase 1 is involved in morphine reward in mice.

    Science.gov (United States)

    Wan, L; Su, L; Xie, Y; Liu, Y; Wang, Y; Wang, Z

    2009-07-07

    Opiate addiction is associated with upregulation of cAMP signaling in the brain. cAMP-responsive element binding protein (CREB), a nuclear transcription factor, is a downstream component of the extracellular signal-regulated protein kinase (ERK) pathway, which has been shown to regulate different physiological and psychological responses of drug addiction. RACK1, the protein receptor for activated C kinase 1, is a multifunctional scaffolding protein known to be a key regulator of various signaling cascades in the CNS. RACK1 functions specifically in integrin mediated activation of ERK cascade and targets active ERK. We examined if RACK1 is involved in the mechanism of drug addiction by regulating CREB in mouse hippocampus and prefrontal cortex. Several expressions were observed. Chronic administration of morphine made the expression of RACK1 and CREB mRNA increase in hippocampus and prefrontal cortex. The expression of RACK1 and CREB protein was strongly positive in CA1, CA3 and dentate gyrus (DG) of the hippocampus of morphine-treated mice brain, especially the pyramidal neurons in the DG of the hippocampus. Using the small interfering RNA technology, we determined that the expression of CREB mRNA was decreased in hippocampus and prefrontal cortex of morphine-treated mice. The expression of RACK1 and CREB protein was negative in CA1, CA3 and DG of hippocampus. These findings suggest that morphine reward can influence the expression of RACK1 in mouse hippocampus and prefrontal cortex through regulating CREB transcription.

  8. Offshore Substrate

    Data.gov (United States)

    California Department of Resources — This shapefile displays the distribution of substrate types from Pt. Arena to Pt. Sal in central/northern California. Originally this data consisted of seven paper...

  9. Searching for Novel Cdk5 Substrates in Brain by Comparative Phosphoproteomics of Wild Type and Cdk5−/− Mice

    Science.gov (United States)

    Contreras-Vallejos, Erick; Utreras, Elías; Bórquez, Daniel A.; Prochazkova, Michaela; Terse, Anita; Jaffe, Howard; Toledo, Andrea; Arruti, Cristina; Pant, Harish C.; Kulkarni, Ashok B.; González-Billault, Christian

    2014-01-01

    Protein phosphorylation is the most common post-translational modification that regulates several pivotal functions in cells. Cyclin-dependent kinase 5 (Cdk5) is a proline-directed serine/threonine kinase which is mostly active in the nervous system. It regulates several biological processes such as neuronal migration, cytoskeletal dynamics, axonal guidance and synaptic plasticity among others. In search for novel substrates of Cdk5 in the brain we performed quantitative phosphoproteomics analysis, isolating phosphoproteins from whole brain derived from E18.5 Cdk5+/+ and Cdk5−/− embryos, using an Immobilized Metal-Ion Affinity Chromatography (IMAC), which specifically binds to phosphorylated proteins. The isolated phosphoproteins were eluted and isotopically labeled for relative and absolute quantitation (iTRAQ) and mass spectrometry identification. We found 40 proteins that showed decreased phosphorylation at Cdk5−/− brains. In addition, out of these 40 hypophosphorylated proteins we characterized two proteins, :MARCKS (Myristoylated Alanine-Rich protein Kinase C substrate) and Grin1 (G protein regulated inducer of neurite outgrowth 1). MARCKS is known to be phosphorylated by Cdk5 in chick neural cells while Grin1 has not been reported to be phosphorylated by Cdk5. When these proteins were overexpressed in N2A neuroblastoma cell line along with p35, serine phosphorylation in their Cdk5 motifs was found to be increased. In contrast, treatments with roscovitine, the Cdk5 inhibitor, resulted in an opposite effect on serine phosphorylation in N2A cells and primary hippocampal neurons transfected with MARCKS. In summary, the results presented here identify Grin 1 as novel Cdk5 substrate and confirm previously identified MARCKS as a a bona fide Cdk5 substrate. PMID:24658276

  10. Structural insights for designed alanine-rich helices: Comparing NMR helicity measures and conformational ensembles from molecular dynamics simulation

    Science.gov (United States)

    Song, Kun; Stewart, James M.; Fesinmeyer, R. Matthew

    2013-01-01

    The temperature dependence of helical propensities for the peptides Ac-ZGG-(KAAAA)3X-NH2 (Z = Y or G, X = A, K, and d-Arg) were studied both experimentally and by molecular dynamics simulations. Good agreement is observed in both the absolute helical propensities as well as relative helical content along the sequence; the global minimum on the calculated free energy landscape corresponds to a single α-helical conformation running from K4 – A18 with some terminal fraying, particularly at the C-terminus. Energy component analysis shows that the single helix state has favorable intramolecular electrostatic energy due to hydrogen bonds, and that less-favorable two-helix globular states have favorable solvation energy. The central lysine residues do not appear to increase helicity; however, both experimental and simulation studies show increasing helicity in the series X = Ala → Lys → d-Arg. This C-capping preference was also experimentally confirmed in Ac-(KAAAA)3X-GY-NH2 and (KAAAA)3X-GY-NH2 sequences. The roles of the C-capping groups, and of lysines throughout the sequence, in the MD-derived ensembles are analyzed in detail. PMID:18428207

  11. Power electronics substrate for direct substrate cooling

    Science.gov (United States)

    Le, Khiet [Mission Viejo, CA; Ward, Terence G [Redondo Beach, CA; Mann, Brooks S [Redondo Beach, CA; Yankoski, Edward P [Corona, CA; Smith, Gregory S [Woodland Hills, CA

    2012-05-01

    Systems and apparatus are provided for power electronics substrates adapted for direct substrate cooling. A power electronics substrate comprises a first surface configured to have electrical circuitry disposed thereon, a second surface, and a plurality of physical features on the second surface. The physical features are configured to promote a turbulent boundary layer in a coolant impinged upon the second surface.

  12. Different forms of MARCKS protein are involved in memory formation in the learning process of imprinting.

    Science.gov (United States)

    Solomonia, Revaz O; Apkhazava, David; Nozadze, Maia; Jackson, Antony P; McCabe, Brian J; Horn, Gabriel

    2008-06-01

    There is strong evidence that a restricted part of the chick forebrain, the IMM (formerly IMHV), stores information acquired through the learning process of visual imprinting. Twenty-four hours after imprinting training, a learning-specific increase in amount of myristoylated, alanine-rich C-kinase substrate (MARCKS) protein is known to occur in the homogenate fraction of IMM. We investigated the two components of this fraction, membrane-bound and cytoplasmic-phosphorylated MARCKS. In IMM, amount of membrane-bound MARCKS, but not of cytoplasmic-phosphorylated MARCKS, increased as chicks learned. No changes were observed for either form of MARCKS in PPN, a control forebrain region. The results indicate that there is a learning-specific increase in membrane-bound, non-phosphorylated MARCKS 24 h after training. This increase might contribute to stabilization of synaptic morphology.

  13. Robust plasmonic substrates

    DEFF Research Database (Denmark)

    Kostiučenko, Oksana; Fiutowski, Jacek; Tamulevicius, Tomas

    2014-01-01

    substrates is presented, which relies on the coverage of gold nanostructures with diamond-like carbon (DLC) thin films of thicknesses 25, 55 and 105 nm. DLC thin films were grown by direct hydrocarbon ion beam deposition. In order to find the optimum balance between optical and mechanical properties...... and breaking. DLC coating with thicknesses between 25 and 105 nm is found to considerably increase the mechanical strength of the substrates while at the same time ensuring conservation of sufficient field enhancements of the gold plasmonic substrates....

  14. B-cell deficiency and severe autoimmunity caused by deficiency of protein kinase C δ.

    Science.gov (United States)

    Salzer, Elisabeth; Santos-Valente, Elisangela; Klaver, Stefanie; Ban, Sol A; Emminger, Wolfgang; Prengemann, Nina Kathrin; Garncarz, Wojciech; Müllauer, Leonhard; Kain, Renate; Boztug, Heidrun; Heitger, Andreas; Arbeiter, Klaus; Eitelberger, Franz; Seidel, Markus G; Holter, Wolfgang; Pollak, Arnold; Pickl, Winfried F; Förster-Waldl, Elisabeth; Boztug, Kaan

    2013-04-18

    Primary B-cell disorders comprise a heterogeneous group of inherited immunodeficiencies, often associated with autoimmunity causing significant morbidity. The underlying genetic etiology remains elusive in the majority of patients. In this study, we investigated a patient from a consanguineous family suffering from recurrent infections and severe lupuslike autoimmunity. Immunophenotyping revealed progressive decrease of CD19(+) B cells, a defective class switch indicated by low numbers of IgM- and IgG-memory B cells, as well as increased numbers of CD21(low) B cells. Combined homozygosity mapping and exome sequencing identified a biallelic splice-site mutation in protein C kinase δ (PRKCD), causing the absence of the corresponding protein product. Consequently, phosphorylation of myristoylated alanine-rich C kinase substrate was decreased, and mRNA levels of nuclear factor interleukin (IL)-6 and IL-6 were increased. Our study uncovers human PRKCD deficiency as a novel cause of common variable immunodeficiency-like B-cell deficiency with severe autoimmunity.

  15. Multiple alternative substrate kinetics.

    Science.gov (United States)

    Anderson, Vernon E

    2015-11-01

    The specificity of enzymes for their respective substrates has been a focal point of enzyme kinetics since the initial characterization of metabolic chemistry. Various processes to quantify an enzyme's specificity using kinetics have been utilized over the decades. Fersht's definition of the ratio kcat/Km for two different substrates as the "specificity constant" (ref [7]), based on the premise that the important specificity existed when the substrates were competing in the same reaction, has become a consensus standard for enzymes obeying Michaelis-Menten kinetics. The expansion of the theory for the determination of the relative specificity constants for a very large number of competing substrates, e.g. those present in a combinatorial library, in a single reaction mixture has been developed in this contribution. The ratio of kcat/Km for isotopologs has also become a standard in mechanistic enzymology where kinetic isotope effects have been measured by the development of internal competition experiments with extreme precision. This contribution extends the theory of kinetic isotope effects to internal competition between three isotopologs present at non-tracer concentrations in the same reaction mix. This article is part of a special issue titled: Enzyme Transition States from Theory and Experiment.

  16. Dewetting on microstructured substrates

    Science.gov (United States)

    Kim, Taehong; Kim, Wonjung

    2016-11-01

    A thin liquid film has an equilibrium thickness in such a way as to minimize the free energy. When a liquid film thickness is out of its equilibrium, the film seeks its equilibrium state, resulting in dynamics of liquid film, which are referred to as wetting and dewetting, depending on the flow direction. We here present a combined experimental and theoretical investigation of dewetting on a substrate with parallel microstructures. Our experiments show that residue may remain on the substrate after dewetting, and residue morphologies can be classified into three modes. Based on our experimental observations, we elucidate how the modes depend on the pattern morphology and contact angle, and develop a model for the contact line motion. Our results provide a basis for controlling the thickness film, which is important for many practical applications such as oil recovery, detergency, lithography, and cleaning. This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (MSIP) (No.2015R1A2A2A04006181).

  17. Maintainable substrate carrier for electroplating

    Science.gov (United States)

    Chen, Chen-An [Milpitas, CA; Abas, Emmanuel Chua [Laguna, PH; Divino, Edmundo Anida [Cavite, PH; Ermita, Jake Randal G [Laguna, PH; Capulong, Jose Francisco S [Laguna, PH; Castillo, Arnold Villamor [Batangas, PH; Ma,; Xiaobing, Diana [Saratoga, CA

    2012-07-17

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The carrier includes a non-conductive carrier body on which the substrates are placed and conductive lines embedded within the carrier body. A plurality of conductive clip attachment parts are attached in a permanent manner to the conductive lines embedded within the carrier body. A plurality of contact clips are attached in a removable manner to the clip attachment parts. The contact clips hold the substrates in place and conductively connecting the substrates with the conductive lines. Other embodiments, aspects and features are also disclosed.

  18. Maintainable substrate carrier for electroplating

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chen-An; Abas, Emmanuel Chua; Divino, Edmundo Anida; Ermita, Jake Randal G.; Capulong, Jose Francisco S.; Castillo, Arnold Villamor; Ma, Diana Xiaobing

    2016-08-02

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The carrier includes a non-conductive carrier body on which the substrates are placed and conductive lines embedded within the carrier body. A plurality of conductive clip attachment parts are attached in a permanent manner to the conductive lines embedded within the carrier body. A plurality of contact clips are attached in a removable manner to the clip attachment parts. The contact clips hold the substrates in place and conductively connecting the substrates with the conductive lines. Other embodiments, aspects and features are also disclosed.

  19. A Novel Radiative Substrate Heater

    OpenAIRE

    CEYLAN, Abdullah; Kaynak, Erdal; ÖZCAN, Şadan; Firat, Tezer

    2004-01-01

    In this work, we have developed a new low cost radiative substrate heater for deposition of high-Tc superconducting thin films. It has all the features required for the preparation of high quality superconducting thin films. It is possible to reach ~ 800 °C substrate temperature with it by using only one 250 W halogen projector bulb.

  20. Soft substrates suppress droplet splashing

    CERN Document Server

    Howland, Christopher J; Style, Robert W; Castrejón-Pita, A A

    2015-01-01

    Droplets splash when they impact dry, flat substrates above a critical velocity that depends on parameters such as droplet size, viscosity and air pressure. We show that substrate stiffness also impacts the splashing threshold by imaging ethanol drops impacting silicone gels of different stiffnesses. Splashing is significantly suppressed: droplets on the softest substrates need over 70% more kinetic energy to splash than they do on rigid substrates. We show that splash suppression is likely to be due to energy losses caused by deformations of soft substrates during the first few microseconds of impact. We find that solids with Youngs modulus $\\lesssim O(10^5)$Pa suppress splashing, in agreement with simple scaling arguments. Thus materials like soft gels and elastomers can be used as simple coatings for effective splash prevention.

  1. Substrate noise coupling in RFICs

    CERN Document Server

    Helmy, Ahmed

    2008-01-01

    Substrate Noise Coupling in RFICs addresses substrate noise coupling in RF and mixed signal ICs when used in a system on chip (SoC) containing digital ICs as well. This trend of integrating RF, mixed signal ICs with large digital ICs is found in many of today's commercial ICs such as single chip Wi-Fi or Bluetooth solutions and is expected to grow rapidly in the future. The book reports modeling and simulation techniques for substrate noise coupling effects in RFICs and introduces isolation structures and design guides to mitigate such effects with the ultimate goal of enhancing the yield of R

  2. Substrate integrated antennas and arrays

    CERN Document Server

    Cheng, Yu Jian

    2015-01-01

    Substrate Integrated Antennas and Arrays provides a single source for cutting-edge information on substrate integrated circuits (SICs), substrate integrated waveguide (SIW) feeding networks, SIW slot array antennas, SIC traveling-wave antennas, SIW feeding antennas, SIW monopulse antennas, and SIW multibeam antennas. Inspired by the author's extensive research, this comprehensive book:Describes a revolutionary SIC-based antenna technique with the potential to replace existing antenna technologiesExamines theoretical and experimental results connected to electrical and mechanical performanceExp

  3. Droplet dynamics on patterned substrates

    Indian Academy of Sciences (India)

    A Dupuis; J M Yeomans

    2005-06-01

    We present a lattice Boltzmann algorithm which can be used to explore the spreading of droplets on chemically and topologically patterned substrates. As an example we use the method to show that the final configuration of a drop on a substrate comprising hydrophobic and hydrophilic stripes can depend sensitively on the dynamical pathway by which the state is reached. We also consider a substrate covered with micron-scale posts and investigate how this can lead to superhydrophobic behaviour. Finally we model how a Namibian desert beetle collects water from the wind.

  4. Direct cooled power electronics substrate

    Science.gov (United States)

    Wiles, Randy H [Powell, TN; Wereszczak, Andrew A [Oak Ridge, TN; Ayers, Curtis W [Kingston, TN; Lowe, Kirk T [Knoxville, TN

    2010-09-14

    The disclosure describes directly cooling a three-dimensional, direct metallization (DM) layer in a power electronics device. To enable sufficient cooling, coolant flow channels are formed within the ceramic substrate. The direct metallization layer (typically copper) may be bonded to the ceramic substrate, and semiconductor chips (such as IGBT and diodes) may be soldered or sintered onto the direct metallization layer to form a power electronics module. Multiple modules may be attached to cooling headers that provide in-flow and out-flow of coolant through the channels in the ceramic substrate. The modules and cooling header assembly are preferably sized to fit inside the core of a toroidal shaped capacitor.

  5. Microstrip antenna on tunable substrate

    Science.gov (United States)

    Jose, K. A.; Varadan, Vijay K.; Varadan, Vasundara V.; Mohanan, P.

    1995-05-01

    The tunable patch antenna configurations are becoming popular and attractive in many aspects. This was mainly due to the advent of ferrite thin film technology and tunable substrate materials. The integration of monolithic microwave circuits and antennas are becoming easy today. In the development of magnetic tuning of microstrip patch on ferrite substrate is presented by Rainville and Harackewiez. Radiation characteristics of such antennas are presented by Pozer. Band width and radiation characteristics of such tunable antennas are measured and compared. Usually the substrate losses are considered in the analysis and metallization losses are assumed to be ideal. The analysis of magnetic tunable radiator including metallization and ferrite substrate losses are presented. However, all such tuning and integration of circuits and antennas are mainly on ferrite substrate due to magnetic tuning. Recently, Varadan et al. established that the BaxSr1-xTiO3 series ferroelectric materials such as Barium Strontium Titanate (BST) are well suited for microwave phase shifter applications. It could be possible to change the dielectric constant of these materials more than 50% depending on the BST composition, by changing the applied bias voltage. Also, the porosity of BST can be controlled during processing to produce dielectric constants in the range of 15 to 1500, with some trade off in tunability. In this paper, we are presenting the possibility of designing a microstrip patch antenna on such tunable substrate. Such antennas are having the major advantage of electronic tunability and compact size.

  6. Porous substrates filled with nanomaterials

    Science.gov (United States)

    Worsley, Marcus A.; Baumann, Theodore F.; Satcher, Jr., Joe H.; Stadermann, Michael

    2014-08-19

    A composition comprising: at least one porous carbon monolith, such as a carbon aerogel, comprising internal pores, and at least one nanomaterial, such as carbon nanotubes, disposed uniformly throughout the internal pores. The nanomaterial can be disposed in the middle of the monolith. In addition, a method for making a monolithic solid with both high surface area and good bulk electrical conductivity is provided. A porous substrate having a thickness of 100 microns or more and comprising macropores throughout its thickness is prepared. At least one catalyst is deposited inside the porous substrate. Subsequently, chemical vapor deposition is used to uniformly deposit a nanomaterial in the macropores throughout the thickness of the porous substrate. Applications include electrical energy storage, such as batteries and capacitors, and hydrogen storage.

  7. Entamoeba histolytica Cysteine Proteinase 5 Evokes Mucin Exocytosis from Colonic Goblet Cells via αvβ3 Integrin.

    Directory of Open Access Journals (Sweden)

    Steve Cornick

    2016-04-01

    Full Text Available Critical to the pathogenesis of intestinal amebiasis, Entamoeba histolytica (Eh induces mucus hypersecretion and degrades the colonic mucus layer at the site of invasion. The parasite component(s responsible for hypersecretion are poorly defined, as are regulators of mucin secretion within the host. In this study, we have identified the key virulence factor in live Eh that elicits the fast release of mucin by goblets cells as cysteine protease 5 (EhCP5 whereas, modest mucus secretion occurred with secreted soluble EhCP5 and recombinant CP5. Coupling of EhCP5-αvβ3 integrin on goblet cells facilitated outside-in signaling by activating SRC family kinases (SFK and focal adhesion kinase that resulted in the activation/phosphorlyation of PI3K at the site of Eh contact and production of PIP3. PKCδ was activated at the EhCP5-αvβ3 integrin contact site that specifically regulated mucin secretion though the trafficking vesicle marker myristoylated alanine-rich C-kinase substrate (MARCKS. This study has identified that EhCP5 coupling with goblet cell αvβ3 receptors can initiate a signal cascade involving PI3K, PKCδ and MARCKS to drive mucin secretion from goblet cells critical in disease pathogenesis.

  8. Phonon scattering in graphene over substrate steps

    DEFF Research Database (Denmark)

    Sevincli, Haldun; Brandbyge, Mads

    2014-01-01

    We calculate the effect on phonon transport of substrate-induced bends in graphene. We consider bending induced by an abrupt kink in the substrate, and provide results for different step-heights and substrate interaction strengths. We find that individual substrate steps reduce thermal conductance...

  9. Semiconductor films on flexible iridium substrates

    Science.gov (United States)

    Goyal, Amit

    2005-03-29

    A laminate semiconductor article includes a flexible substrate, an optional biaxially textured oxide buffer system on the flexible substrate, a biaxially textured Ir-based buffer layer on the substrate or the buffer system, and an epitaxial layer of a semiconductor. Ir can serve as a substrate with an epitaxial layer of a semiconductor thereon.

  10. Sensor Technologies on Flexible Substrates

    Science.gov (United States)

    Koehne, Jessica

    2016-01-01

    NASA Ames has developed sensor technologies on flexible substrates integrated into textiles for personalized environment monitoring and human performance evaluation. Current technologies include chemical sensing for gas leak and event monitoring and biological sensors for human health and performance monitoring. Targeted integration include next generation EVA suits and flexible habitats.

  11. Neurobiological Substrates of Tourette's Disorder

    NARCIS (Netherlands)

    Leckman, James F.; Bloch, Michael H.; Smith, Megan E.; Larabi, Daouia; Hampson, Michelle

    2010-01-01

    Objective: This article reviews the available scientific literature concerning the neurobiological substrates of Tourette's disorder (TD). Methods: The electronic databases of PubMed, ScienceDirect, and PsycINFO were searched for relevant studies using relevant search terms. Results: Neuropathologic

  12. Modeling graphene-substrate interactions

    NARCIS (Netherlands)

    Amlaki, Taher

    2016-01-01

    In this thesis I focussed on the interactions between graphene-like materials (grapheme and germanene) and various substrates. The attractive properties of graphene like a high carrier mobility, its single-atomic thickness and its theoretical magic have made graphene a very popular and promising can

  13. Substrates: Chemical characteristics and preparation

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    In this chapter the characteristics of substrates will be discussed with respect to their effects on plant nutrition. Therefore, the chemical composition will be taken into account in the first place, because the mineral elements present in the material can be directly available to plants or can bec

  14. PREFACE: Cell-substrate interactions Cell-substrate interactions

    Science.gov (United States)

    Gardel, Margaret; Schwarz, Ulrich

    2010-05-01

    One of the most striking achievements of evolution is the ability to build cellular systems that are both robust and dynamic. Taken by themselves, both properties are obvious requirements: robustness reflects the fact that cells are there to survive, and dynamics is required to adapt to changing environments. However, it is by no means trivial to understand how these two requirements can be implemented simultaneously in a physical system. The long and difficult quest to build adaptive materials is testimony to the inherent difficulty of this goal. Here materials science can learn a lot from nature, because cellular systems show that robustness and dynamics can be achieved in a synergetic fashion. For example, the capabilities of tissues to repair and regenerate are still unsurpassed in the world of synthetic materials. One of the most important aspects of the way biological cells adapt to their environment is their adhesive interaction with the substrate. Numerous aspects of the physiology of metazoan cells, including survival, proliferation, differentiation and migration, require the formation of adhesions to the cell substrate, typically an extracellular matrix protein. Adhesions guide these diverse processes both by mediating force transmission from the cell to the substrate and by controlling biochemical signaling pathways. While the study of cell-substrate adhesions is a mature field in cell biology, a quantitative biophysical understanding of how the interactions of the individual molecular components give rise to the rich dynamics and mechanical behaviors observed for cell-substrate adhesions has started to emerge only over the last decade or so. The recent growth of research activities on cell-substrate interactions was strongly driven by the introduction of new physical techniques for surface engineering into traditional cell biological work with cell culture. For example, microcontact printing of adhesive patterns was used to show that cell fate depends

  15. Graphene folding on flat substrates

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaoming; Zhao, Yadong; Ke, Changhong, E-mail: cke@binghamton.edu [Department of Mechanical Engineering, State University of New York at Binghamton, Binghamton, New York 13902 (United States); Zhang, Liuyang; Wang, Xianqiao [College of Engineering, University of Georgia, Athens, Georgia 30602 (United States)

    2014-10-28

    We present a combined experimental-theoretical study of graphene folding on flat substrates. The structure and deformation of the folded graphene sheet are experimentally characterized by atomic force microscopy. The local graphene folding behaviors are interpreted based on nonlinear continuum mechanics modeling and molecular dynamics simulations. Our study on self-folding of a trilayer graphene sheet reports a bending stiffness of about 6.57 eV, which is about four times the reported values for monolayer graphene. Our results reveal that an intriguing free sliding phenomenon occurs at the interlayer van der Waals interfaces during the graphene folding process. This work demonstrates that it is a plausible venue to quantify the bending stiffness of graphene based on its self-folding conformation on flat substrates. The findings reported in this work are useful to a better understanding of the mechanical properties of graphene and in the pursuit of its applications.

  16. Methods of repairing a substrate

    Science.gov (United States)

    Riedell, James A. (Inventor); Easler, Timothy E. (Inventor)

    2011-01-01

    A precursor of a ceramic adhesive suitable for use in a vacuum, thermal, and microgravity environment. The precursor of the ceramic adhesive includes a silicon-based, preceramic polymer and at least one ceramic powder selected from the group consisting of aluminum oxide, aluminum nitride, boron carbide, boron oxide, boron nitride, hafnium boride, hafnium carbide, hafnium oxide, lithium aluminate, molybdenum silicide, niobium carbide, niobium nitride, silicon boride, silicon carbide, silicon oxide, silicon nitride, tin oxide, tantalum boride, tantalum carbide, tantalum oxide, tantalum nitride, titanium boride, titanium carbide, titanium oxide, titanium nitride, yttrium oxide, zirconium boride, zirconium carbide, zirconium oxide, and zirconium silicate. Methods of forming the ceramic adhesive and of repairing a substrate in a vacuum and microgravity environment are also disclosed, as is a substrate repaired with the ceramic adhesive.

  17. Ketone Bodies as Brain Substrates

    OpenAIRE

    Silva, Paula Sofia Valente da

    2015-01-01

    SILVA, Paula Sofia Valente da - Ketone Bodies as Brain Substrates. Coimbra : [s.n.], 2015. Dissertação de Mestrado em Bioquimica. Since their discovery as a marker for diabetic ketoacidosis, ketone bodies have become known for their therapeutic role as effective agents in refractory epilepsy and a diet specifically designed to increase ketone bodies’ levels in circulation has been often prescribed as treatment. In the classical ketogenic diet, intake of even small additional amounts of car...

  18. Nanostructured Substrates for Optical Sensing

    OpenAIRE

    Kemling, Jonathan W.; Qavi, Abraham J.; Bailey, Ryan C.; Suslick, Kenneth S

    2011-01-01

    Sensors that change color have the advantages of versatility, ease of use, high sensitivity, and low cost. The recent development of optically based chemical sensing platforms has increasingly employed substrates manufactured with advanced processing or fabrication techniques to provide precise control over shape and morphology of the sensor micro- and nano-structure. New sensors have resulted with improved capabilities for a number of sensing applications, including the detection of biomolec...

  19. Substrate analogues for isoprenoid enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Stremler, K.E.

    1987-01-01

    Diphosphonate analogues of geranyl diphosphate, resistant to degradation by phosphatases, were found to be alternate substrates for the reaction with farnesyl diphosphate synthetase isolated from avian liver. The difluoromethane analogue was shown to be the better alternate substrate, in agreement with solvolysis results which indicate that the electronegativity of the difluoromethylene unit more closely approximates that of the normal bridging oxygen. The usefulness of the C/sub 10/ difluoro analogue, for detecting low levels of isoprenoid enzymes in the presence of high levels of phosphatase activity, was demonstrated with a cell-free preparation from lemon peel. A series of C/sub 5/ through C/sub 15/ homoallylic and allylic diphosphonates, as well as two 5'-nucleotide diphosphonates, was prepared in high overall yield using the activation-displacement sequence. Radiolabeled samples of several of the allylic diphosphonates were prepared with tritium located at C1. A series of geraniols, stereospecifically deuterated at C1, was prepared. The enantiomeric purities and absolute configurations were determined by derivatization as the mandelate esters for analysis by /sup 1/H NMR. The stereochemistry of the activation-displacement sequence was examined using C1-deuterated substrates.

  20. Insulin receptor substrate-1 (IRS-1 associates with small nucleolar RNA which contributes to ribosome biogenesis

    Directory of Open Access Journals (Sweden)

    Atsufumi eOzoe

    2014-03-01

    Full Text Available Insulin receptor substrates (IRSs are well known to play crucial roles in mediating intracellular signals of insulin-like growth factors (IGFs/insulin. Previously we showed that IRS-1 forms high molecular mass complexes containing RNAs. To identify RNAs in IRS-1 complexes, we performed UV cross-linking and immunoprecipitation (CLIP analysis using HEK293 cells expressing FLAG-IRS-1 and FLAG-IRS-2. We detected the radioactive signals in the immunoprecipitates of FLAG-IRS-1 proportional to the UV irradiation, but not in the immunoprecipitates of FLAG-IRS-2, suggesting the direct contact of RNAs with IRS-1. RNAs cross-linked to IRS-1 were then amplified by RT-PCR, followed by sequence analysis. We isolated sequence tags attributed to 25 messenger RNAs and 8 non-coding RNAs, including small nucleolar RNAs (snoRNAs. We focused on the interaction of IRS-1 with U96A snoRNA (U96A and its host Rack1 (receptor for activated C kinase 1 pre-mRNA. We confirmed the interaction of IRS-1 with U96A, and with RACK1 pre-mRNA by immunoprecipitation with IRS-1 followed by Northern blotting or RT-PCR analyses. Mature U96A in IRS-1-/- mouse embryonic fibroblasts was quantitatively less than WT. We also found that a part of nuclear IRS-1 is localized in the Cajal body, a nuclear subcompartment where snoRNA mature. The unanticipated function of IRS-1 in snoRNA biogenesis highlights the potential of RNA-associated IRS-1 complex to open a new line of investigation to dissect the novel mechanisms regulating IGFs/insulin-mediated biological events.

  1. Carbon Nanotube Patterning on a Metal Substrate

    Science.gov (United States)

    Nguyen, Cattien V. (Inventor)

    2016-01-01

    A CNT electron source, a method of manufacturing a CNT electron source, and a solar cell utilizing a CNT patterned sculptured substrate are disclosed. Embodiments utilize a metal substrate which enables CNTs to be grown directly from the substrate. An inhibitor may be applied to the metal substrate to inhibit growth of CNTs from the metal substrate. The inhibitor may be precisely applied to the metal substrate in any pattern, thereby enabling the positioning of the CNT groupings to be more precisely controlled. The surface roughness of the metal substrate may be varied to control the density of the CNTs within each CNT grouping. Further, an absorber layer and an acceptor layer may be applied to the CNT electron source to form a solar cell, where a voltage potential may be generated between the acceptor layer and the metal substrate in response to sunlight exposure.

  2. Known Good Substrates Year 1

    Science.gov (United States)

    2007-12-05

    Monotonic Decrease of VC-VSi, SN1, and SN2 with ↑ ρ (↓ [N])” Known Good Substrates Contractor: Dow Corning Corporation Contract No. N00014-05-C-0324...Vapor Transport (CVT). The key essence of the CVT approach is to control the growth process by strategic controlled chemical reactions of the source...efficacy for its use in 4H n+ SiC crystal growth. The approach consists of the following steps: • Reaction cell design/modeling and chemical

  3. Substrate preparation by contactless mechanochemical polish

    Science.gov (United States)

    Rotter, S.; Lachish, U.; El-Hanany, U.

    1985-10-01

    A simple, yet effective, polishing technique for substrate preparation is presented. It is contactless chemical polish which does not introduce any defects into the substrate during the process. The method can be readily adopted in all cases where chemical polishing is practical for substrate preparation. Results similar to those obtained by the more sophisticated hydroplaning method can be achieved.

  4. A new lime material for container substrates

    Science.gov (United States)

    The primary component in greenhouse potting substrates is sphagnum peatmoss. Substrate solution pH of non-amended peatmoss ranges from 4.0 to 4.5. Ideal pH for most greenhouse floriculture crops ranges from 5.8 to 6.2. Dolomitic lime is most often used to elevate substrate pH in peatmoss-based me...

  5. Substrate mediated enzyme prodrug therapy.

    Directory of Open Access Journals (Sweden)

    Betina Fejerskov

    Full Text Available In this report, we detail Substrate Mediated Enzyme Prodrug Therapy (SMEPT as a novel approach in drug delivery which relies on enzyme-functionalized cell culture substrates to achieve a localized conversion of benign prodrug(s into active therapeutics with subsequent delivery to adhering cells or adjacent tissues. For proof-of-concept SMEPT, we use surface adhered micro-structured physical hydrogels based on poly(vinyl alcohol, β-glucuronidase enzyme and glucuronide prodrugs. We demonstrate enzymatic activity mediated by the assembled hydrogel samples and illustrate arms of control over rate of release of model fluorescent cargo. SMEPT was not impaired by adhering cells and afforded facile time - and dose - dependent uptake of the in situ generated fluorescent cargo by hepatic cells, HepG2. With the use of a glucuronide derivative of an anticancer drug, SN-38, SMEPT afforded a decrease in cell viability to a level similar to that achieved using parent drug. Finally, dose response was achieved using SMEPT and administration of judiciously chosen concentration of SN-38 glucuronide prodrug thus revealing external control over drug delivery using drug eluting surface. We believe that this highly adaptable concept will find use in diverse biomedical applications, specifically surface mediated drug delivery and tissue engineering.

  6. Small droplets on superhydrophobic substrates.

    Science.gov (United States)

    Gross, Markus; Varnik, Fathollah; Raabe, Dierk; Steinbach, Ingo

    2010-05-01

    We investigate the wetting behavior of liquid droplets on rough hydrophobic substrates for the case of droplets that are of comparable size to the surface asperities. Using a simple three-dimensional analytical free-energy model, we have shown in a recent letter [M. Gross, F. Varnik, and D. Raabe, EPL 88, 26002 (2009)] that, in addition to the well-known Cassie-Baxter and Wenzel states, there exists a further metastable wetting state where the droplet is immersed into the texture to a finite depth, yet not touching the bottom of the substrate. Due to this new state, a quasistatically evaporating droplet can be saved from going over to the Wenzel state and instead remains close to the top of the surface. In the present paper, we give an in-depth account of the droplet behavior based on the results of extensive computer simulations and an improved theoretical model. In particular, we show that releasing the assumption that the droplet is pinned at the outer edges of the pillars improves the analytical results for larger droplets. Interestingly, all qualitative aspects, such as the existence of an intermediate minimum and the "reentrant transition," remain unchanged. We also give a detailed description of the evaporation process for droplets of varying sizes. Our results point out the role of droplet size for superhydrophobicity and give hints for achieving the desired wetting properties of technically produced materials.

  7. Phonon scattering in graphene over substrate steps

    Energy Technology Data Exchange (ETDEWEB)

    Sevinçli, H., E-mail: haldunsevincli@iyte.edu.tr [Department of Materials Science and Engineering, Izmir Institute of Technology, Gülbahçe Kampüsü, 35430 Urla, Izmir (Turkey); Department of Micro- and Nano-technology (DTU Nanotech), Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark); Brandbyge, M., E-mail: mads.brandbyge@nanotech.dtu.dk [Department of Micro- and Nano-technology (DTU Nanotech), Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark); Center for Nanostructured Graphene(CNG), Department of Micro- and Nano-technology, Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark)

    2014-10-13

    We calculate the effect on phonon transport of substrate-induced bends in graphene. We consider bending induced by an abrupt kink in the substrate, and provide results for different step-heights and substrate interaction strengths. We find that individual substrate steps reduce thermal conductance in the range between 5% and 47%. We also consider the transmission across linear kinks formed by adsorption of atomic hydrogen at the bends and find that individual kinks suppress thermal conduction substantially, especially at high temperatures. Our analysis show that substrate irregularities can be detrimental for thermal conduction even for small step heights.

  8. Method For Producing Mechanically Flexible Silicon Substrate

    KAUST Repository

    Hussain, Muhammad Mustafa

    2014-08-28

    A method for making a mechanically flexible silicon substrate is disclosed. In one embodiment, the method includes providing a silicon substrate. The method further includes forming a first etch stop layer in the silicon substrate and forming a second etch stop layer in the silicon substrate. The method also includes forming one or more trenches over the first etch stop layer and the second etch stop layer. The method further includes removing the silicon substrate between the first etch stop layer and the second etch stop layer.

  9. Automated cassette-to-cassette substrate handling system

    Science.gov (United States)

    Kraus, Joseph Arthur; Boyer, Jeremy James; Mack, Joseph; DeChellis, Michael; Koo, Michael

    2014-03-18

    An automated cassette-to-cassette substrate handling system includes a cassette storage module for storing a plurality of substrates in cassettes before and after processing. A substrate carrier storage module stores a plurality of substrate carriers. A substrate carrier loading/unloading module loads substrates from the cassette storage module onto the plurality of substrate carriers and unloads substrates from the plurality of substrate carriers to the cassette storage module. A transport mechanism transports the plurality of substrates between the cassette storage module and the plurality of substrate carriers and transports the plurality of substrate carriers between the substrate carrier loading/unloading module and a processing chamber. A vision system recognizes recesses in the plurality of substrate carriers corresponding to empty substrate positions in the substrate carrier. A processor receives data from the vision system and instructs the transport mechanism to transport substrates to positions on the substrate carrier in response to the received data.

  10. Stiff substrates enhance cultured neuronal network activity.

    Science.gov (United States)

    Zhang, Quan-You; Zhang, Yan-Yan; Xie, Jing; Li, Chen-Xu; Chen, Wei-Yi; Liu, Bai-Lin; Wu, Xiao-an; Li, Shu-Na; Huo, Bo; Jiang, Lin-Hua; Zhao, Hu-Cheng

    2014-08-28

    The mechanical property of extracellular matrix and cell-supporting substrates is known to modulate neuronal growth, differentiation, extension and branching. Here we show that substrate stiffness is an important microenvironmental cue, to which mouse hippocampal neurons respond and integrate into synapse formation and transmission in cultured neuronal network. Hippocampal neurons were cultured on polydimethylsiloxane substrates fabricated to have similar surface properties but a 10-fold difference in Young's modulus. Voltage-gated Ca(2+) channel currents determined by patch-clamp recording were greater in neurons on stiff substrates than on soft substrates. Ca(2+) oscillations in cultured neuronal network monitored using time-lapse single cell imaging increased in both amplitude and frequency among neurons on stiff substrates. Consistently, synaptic connectivity recorded by paired recording was enhanced between neurons on stiff substrates. Furthermore, spontaneous excitatory postsynaptic activity became greater and more frequent in neurons on stiff substrates. Evoked excitatory transmitter release and excitatory postsynaptic currents also were heightened at synapses between neurons on stiff substrates. Taken together, our results provide compelling evidence to show that substrate stiffness is an important biophysical factor modulating synapse connectivity and transmission in cultured hippocampal neuronal network. Such information is useful in designing instructive scaffolds or supporting substrates for neural tissue engineering.

  11. Mosaic of Commemorative Microscope Substrate

    Science.gov (United States)

    2008-01-01

    Written by electron beam lithography in the Microdevices Laboratory of NASA's Jet Propulsion Laboratory, this Optical Microscope substrate helps the Phoenix Mars Mission science team learn how to assemble individual microscope images into a mosaic by aligning rows of text. Each line is about 0.1 millimeter tall, the average thickness of a human hair. Except for the Mogensen twins, the names are of babies born and team members lost during the original development of MECA (the Microscopy, Electrochemistry and Conductivity Analyzer) for the canceled 2001 Mars lander mission. The plaque also acknowledges the MECA 2001 principal investigator, now retired. This image was taken by the MECA Optical Microscope on Sol 111, or the 111th day of the Phoenix mission (Sept. 16, 2008). The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  12. Quality Of Electrophotographic Prints On Foil Substrates

    Directory of Open Access Journals (Sweden)

    Rozália Szentgyörgyvölgyi

    2011-05-01

    Full Text Available Electrophotographic printing uses many types of substrates, our study focuses on plastic substrates. Six types ofregular and self-adhesive foil substrates were chosen to be printed using two electrophotographic presses: XeroxColour 1000 Press and Canon imagePress C7000VP. A test chart containing tone value scales and a set of samplesfor profiling was created, spectrophotomety and densitometry was applied to obtain the optical and colorimetricproperties of the substrates investigated. Xerox Color 1000 Press produced larger densities and tone value increaseon every type of substrate. The largest TVI values and reproducible colour gamut was observed on the smoothestfoil in case of both presses. Large colour differences were found between patches of full tone process colors on thedifferent substrates investigated.

  13. Non-permeable substrate carrier for electroplating

    Energy Technology Data Exchange (ETDEWEB)

    Abas, Emmanuel Chua; Chen, Chen-An; Ma, Diana Xiaobing; Ganti, Kalyana Bhargava

    2012-11-27

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The substrate carrier comprises a non-conductive carrier body on which the substrates are to be held. Electrically-conductive lines are embedded within the carrier body, and a plurality of contact clips are coupled to the electrically-conductive lines embedded within the carrier body. The contact clips hold the substrates in place and electrically couple the substrates to the electrically-conductive lines. The non-conductive carrier body is continuous so as to be impermeable to flow of electroplating solution through the non-conductive carrier body. Other embodiments, aspects and features are also disclosed.

  14. Non-permeable substrate carrier for electroplating

    Energy Technology Data Exchange (ETDEWEB)

    Abas, Emmanuel Chua; Chen, Chen-an; Ma, Diana Xiaobing; Ganti, Kalyana; Divino, Edmundo Anida; Ermita, Jake Randal G.; Capulong, Jose Francisco S.; Castillo, Arnold Villamor

    2015-12-29

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The substrate carrier comprises a non-conductive carrier body on which the substrates are to be held. Electrically-conductive lines are embedded within the carrier body, and a plurality of contact clips are coupled to the electrically-conductive lines embedded within the carrier body. The contact clips hold the substrates in place and electrically couple the substrates to the electrically-conductive lines. The non-conductive carrier body is continuous so as to be impermeable to flow of electroplating solution through the non-conductive carrier body. Other embodiments, aspects and features are also disclosed.

  15. Understanding the substrate specificity of conventional calpains.

    Science.gov (United States)

    Sorimachi, Hiroyuki; Mamitsuka, Hiroshi; Ono, Yasuko

    2012-09-01

    Calpains are intracellular Ca(2+)-dependent Cys proteases that play important roles in a wide range of biological phenomena via the limited proteolysis of their substrates. Genetic defects in calpain genes cause lethality and/or functional deficits in many organisms, including humans. Despite their biological importance, the mechanisms underlying the action of calpains, particularly of their substrate specificities, remain largely unknown. Studies show that certain sequence preferences influence calpain substrate recognition, and some properties of amino acids have been related successfully to substrate specificity and to the calpains' 3D structure. The full spectrum of this substrate specificity, however, has not been clarified using standard sequence analysis algorithms, e.g., the position-specific scoring-matrix method. More advanced bioinformatics techniques were used recently to identify the substrate specificities of calpains and to develop a predictor for calpain cleavage sites, demonstrating the potential of combining empirical data acquisition and machine learning. This review discusses the calpains' substrate specificities, introducing the benefits of bioinformatics applications. In conclusion, machine learning has led to the development of useful predictors for calpain cleavage sites, although the accuracy of the predictions still needs improvement. Machine learning has also elucidated information about the properties of calpains' substrate specificities, including a preference for sequences over secondary structures and the existence of a substrate specificity difference between two similar conventional calpains, which has never been indicated biochemically.

  16. Nanowires and nanoneedles nucleation on vicinal substrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xu, E-mail: zhangxubetter@gmail.com [Henan Key Laboratory of Laser and Opto-electric Information Technology, School of Information Engineering, Zhengzhou University, Zhengzhou 450052 (China); Xie, Dan; Huang, Genling [Zhengzhou Railway Vocational and Technical College, Zhengzhou 450052 (China); Sun, Xiao-Hong [Henan Key Laboratory of Laser and Opto-electric Information Technology, School of Information Engineering, Zhengzhou University, Zhengzhou 450052 (China)

    2015-01-01

    An analytic stress-driven nucleation model of nanowires (NWs) and nanoneedles (NNs) growing on a mismatched vicinal substrate is proposed. It is demonstrated that the formation enthalpy of NWs and NNs is a function of three independent variables, the base radius, aspect ratio and miscut angle of the vicinal surface. Theoretical analysis shows that the minimum nucleation barrier of an island decreases with increment of substrate misorientation, which means the nucleation of islands on a vicinal substrate is more favorable than that on a flat substrate.

  17. Adhesion of rhodium films on metallic substrates

    Energy Technology Data Exchange (ETDEWEB)

    Marot, L. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)], E-mail: laurent.marot@unibas.ch; Covarel, G.; Tuilier, M.-H. [Laboratoire Mecanique, Materiaux et Procedes de Fabrication, Pole STIC-SPI-Math 61 rue Albert Camus, Universite de Haute-Alsace, F-68093 - Mulhouse Cedex (France); Steiner, R.; Oelhafen, P. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)

    2008-09-01

    Rhodium coated metallic films were prepared by magnetron sputtering on metallic substrates. All films were elaborated in same conditions on copper, molybdenum and stainless steel. Adhesion strength tests were carried out by scratch test. The results reveal that the adhesion strength between the film and the substrate is influenced by the hardness of the substrate. Increase of deposition temperature improves the adhesion of the coating. In addition, pre-treatment of substrates by a filtered cathodic vacuum arc and the layer thickness have has some effects on the final adhesion strength.

  18. Casimir Forces between Nanoparticles and Substrates

    CERN Document Server

    Román-Velázquez, C E; Villarreal, C; Esquivel-Sirvent, R; Noguez, Cecilia

    2002-01-01

    We study the Casimir force between a nanoparticle and a substrate. We consider the interaction of metal nanoparticles with different substrates within the dipolar approximation. We study the force as a function of the distance for gold and potassium spheres, which are over a substrate of titanium dioxide, sapphire and a perfect conductor. We show that Casimir force is important in systems at the nanometer scale. We study the force as a function of the material properties, radii of the spheres, and the distance between the sphere and the substrate.

  19. Photovoltaic cell with nano-patterned substrate

    Science.gov (United States)

    Cruz-Campa, Jose Luis; Zhou, Xiaowang; Zubia, David

    2016-10-18

    A photovoltaic solar cell comprises a nano-patterned substrate layer. A plurality of nano-windows are etched into an intermediate substrate layer to form the nano-patterned substrate layer. The nano-patterned substrate layer is positioned between an n-type semiconductor layer composed of an n-type semiconductor material and a p-type semiconductor layer composed of a p-type semiconductor material. Semiconductor material accumulates in the plurality of nano-windows, causing a plurality of heterojunctions to form between the n-type semiconductor layer and the p-type semiconductor layer.

  20. Cancer and the metastatic substrate

    Science.gov (United States)

    Arvelo, Francisco; Sojo, Felipe; Cotte, Carlos

    2016-01-01

    Seventy percent of cancer patients have detectable metastases when they receive a diagnosis and 90% of cancer deaths result from metastases. These two facts emphasise the urgency for research to study the mechanisms and processes that enable metastasis. We need to develop a greater understanding of the cellular and molecular mechanisms that cause metastasis and also we need to do more. We must also consider the micro- and macro-environmental factors that influence this disease. Studying this environmental context has led us to update the ‘seed and soil’ hypothesis which dates back to the 19th century. This theory describes cancerous cells as seeds and the substrate as the soil in target organs though this may seem antiquated. Nonetheless, the tissue specificity that researchers have recently observed in metastatic colonisation supports the validity of the seed and soil theory. We now know that the metastatic potential of a tumour cell depends on multiple, reciprocal interactions between the primary tumour and distant sites. These interactions determine tumour progression. Studies of metastasis have allowed us to develop treatments that focus on therapeutic effectiveness. These new treatments account for the frequent metastasis of some tumours to target organs such as bones, lungs, brain, and liver. The purpose of this review is first to describe interactions between the cellular and molecular entities and the target organ tumour environment that enables metastasis. A second aim is to describe the complex mechanisms that mediate these interactions. PMID:28105072

  1. Surface Modification of Nanocellulose Substrates

    Science.gov (United States)

    Zoppe, Justin Orazio

    Cellulose fibers constitute an important renewable raw material that is utilized in many commercial applications in non-food, paper, textiles and composite materials. Chemical functionalization is an important approach for improving the properties of cellulose based materials. Different approaches are used to graft polymeric chains onto cellulose substrates, which can be classified by two principal routes, namely 'grafting onto' or 'grafting from' methods. Never-dried cellulose nanocrystals (CNCs) or nanowhiskers produced from sulfuric acid hydrolysis of ramie fibers were used as substrates for surface chemical functionalization with various macromolecules. In addition, the use of cellulose nanocrystals to reinforce poly(epsilon-caprolactone) (PCL) nanofibers was studied. Chemical grafting with low molecular weight polycaprolactone diol onto cellulose nanocrystals was carried out in an attempt to improve the interfacial adhesion with the fiber matrix. Significant improvements in the mechanical properties of the nanofibers after reinforcement with unmodified cellulose nanocrystals were confirmed. Fiber webs from PCL reinforced with 2.5% unmodified CNCs showed ca. 1.5-fold increase in Young's modulus and ultimate strength compared to PCL webs. The CNCs were also grafted with poly(N-isopropylacrylamide) (poly(NiPAAm)) brushes via surface-initiated single-electron transfer living radical polymerization (SI-SETLRP) under various conditions at room temperature. The grafting process depended on the initiator and/or monomer concentrations used. No observable damage occurred to the CNCs after grafting, as determined by X-ray diffraction. Size exclusion chromatography analyses of polymer chains cleaved from the cellulose nanocrystals indicated that a higher degree of polymerization was achieved by increasing initiator or monomer loading, most likely caused by local heterogeneities yielding higher rates of polymerization. In addition, the colloidal stability and thermo

  2. Substrate tolerant direct block copolymer nanolithography

    DEFF Research Database (Denmark)

    Li, Tao; Wang, Zhongli; Schulte, Lars

    2016-01-01

    simplifies the main stream BC lithography process, showing a broad substrate tolerance and allowing for efficient pattern transfer over wafer scale. PDMS-rich poly(styrene-b-dimethylsiloxane) (PS-b-PDMS) copolymers are directly applied on substrates including polymers, silicon and graphene. A single oxygen...

  3. Direct transfer of graphene onto flexible substrates

    Science.gov (United States)

    Pimenta, Luiz Gustavo; Song, Yi; Zeng, Tingying; Dresselhaus, Mildred; Kong, Jing; Araujo, Paulo

    2014-03-01

    We explore the direct transfer via lamination of chemical vapor deposition graphene onto different flexible substrates. The transfer method investigated here is fast, simple, and does not require an intermediate transfer membrane, such as polymethylmethacrylate. Various substrates of general interest in research and industry were studied including polytetrafluoroethylene filter membranes, PVC, cellulose nitrate/cellulose acetate filter membranes, polycarbonate, paraffin, polyethylene terephthalate, paper, and cloth. By comparing the properties of these substrates, two critical factors to ensure a successful transfer on bare substrates were identified: the substrate's hydrophobicity and good contact between the substrate and graphene. For substrates that do not satisfy those requirements, polymethylmethacrylate can be used as a surface modifier or glue to ensure successful transfer. Our results can be applied to facilitate present processes and open up directions for applications of chemical vapor deposition (CVD) graphene on flexible substrates. A broad range of applications of CVD graphene can be envisioned, including fabrication of graphene devices for opto/organic electronics, graphene membranes for gas/liquid separation, and ubiquitous electronics with graphene.

  4. Buffer layers on biaxially textured metal substrates

    Science.gov (United States)

    Shoup, Shara S.; Paranthamam, Mariappan; Beach, David B.; Kroeger, Donald M.; Goyal, Amit

    2001-01-01

    A method is disclosed for forming a biaxially textured buffer layer on a biaxially oriented metal substrate by using a sol-gel coating technique followed by pyrolyzing/annealing in a reducing atmosphere. This method is advantageous for providing substrates for depositing electronically active materials thereon.

  5. Designing specificity of protein-substrate interactions

    NARCIS (Netherlands)

    Coluzza, I.; Frenkel, D.

    2004-01-01

    One of the key properties of biological molecules is that they can bind strongly to certain substrates yet interact only weakly with the very large number of other molecules that they encounter. Using a simple lattice model, we test several methods to design molecule-substrate binding specificity. W

  6. A signal-substrate match in the substrate-borne component of a multimodal courtship display

    Directory of Open Access Journals (Sweden)

    Damian O. ELIAS, Andrew C. MASON, Eileen A. HEBETS

    2010-06-01

    Full Text Available The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at very small scales. Nevertheless, natural selection is expected to select for signals well-suited to effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider Schizocosa stridulans Stratton 1991. We first explore the transmission characteristics of this important signaling modality by playing recorded substrate-borne signals through three different substrates (leaf litter, pine litter, and red clay and measuring the propagated signal. We found that the substrate-borne signal of S. stridulans attenuates the least on leaf litter, the substrate upon which the species is naturally found. Next, by assessing mating success with artificially muted and non-muted males across different signaling substrates (leaf litter, pine litter, and sand, we explored the relationship between substrate-borne signaling and substrate for mating success. We found that muted males were unsuccessful in obtaining copulations regardless of substrate, while mating success was dependent on the signaling substrate for non-muted males. For non-muted males, more males copulated on leaf litter than any other substrate. Taken together, these results confirm the importance of substrate-borne signaling in S. stridulans and suggest a match between signal properties and signal efficacy – leaf litter transmits the signal most effectively and males are most successful in obtaining copulations on leaf litter [Current Zoology 56 (3: 370–378, 2010].

  7. DIFFERENTIAL DISTRIBUTION OF PROTEIN-KINASE-C (PKC-ALPHA-BETA AND PKC-GAMMA) ISOENZYME IMMUNOREACTIVITY IN THE CHICK BRAIN

    NARCIS (Netherlands)

    VANDERZEE, EA; BOLHUIS, JJ; SOLOMONIA, RO; HORN, G; LUITEN, PGM

    1995-01-01

    Protein kinase C (PKC) is involved in neural plasticity. The phosphorylation of the myristoylated alanine-rich protein kinase C substrate (MARCKS) in the left intermediate and medial hyperstriatum ventrale (IMHV) of the chick brain has been shown previously to correlate significantly with the streng

  8. Differential distribution of protein kinase C (PKCαβ and PKCγ) isoenzyme immunoreactivity in the chick brain

    NARCIS (Netherlands)

    Zee, Eddy A. van der; Bolhuis, Johan J.; Solomonia, Revaz O.; Horn, Gabriel; Luiten, Paul G.M.

    1995-01-01

    Protein kinase C (PKC) is involved in neural plasticity. The phosphorylation of the myristoylated alanine-rich protein kinase C substrate (MARCKS) in the left intermediate and medial hyperstriatum ventrale (IMHV) of the chick brain has been shown previously to correlate significantly with the streng

  9. Electron mobility calculation for graphene on substrates

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, Hideki; Ogawa, Matsuto [Department of Electrical and Electronic Engineering, Graduate School of Engineering, Kobe University, 1-1, Rokko-dai, Nada-ku, Kobe 657-8501 (Japan); Tsuchiya, Hideaki, E-mail: tsuchiya@eedept.kobe-u.ac.jp [Department of Electrical and Electronic Engineering, Graduate School of Engineering, Kobe University, 1-1, Rokko-dai, Nada-ku, Kobe 657-8501 (Japan); Japan Science and Technology Agency, CREST, Chiyoda, Tokyo 102-0075 (Japan); Kamakura, Yoshinari; Mori, Nobuya [Japan Science and Technology Agency, CREST, Chiyoda, Tokyo 102-0075 (Japan); Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan)

    2014-08-28

    By a semiclassical Monte Carlo method, the electron mobility in graphene is calculated for three different substrates: SiO{sub 2}, HfO{sub 2}, and hexagonal boron nitride (h-BN). The calculations account for polar and non-polar surface optical phonon (OP) scatterings induced by the substrates and charged impurity (CI) scattering, in addition to intrinsic phonon scattering in pristine graphene. It is found that HfO{sub 2} is unsuitable as a substrate, because the surface OP scattering of the substrate significantly degrades the electron mobility. The mobility on the SiO{sub 2} and h-BN substrates decreases due to CI scattering. However, the mobility on the h-BN substrate exhibits a high electron mobility of 170 000 cm{sup 2}/(V·s) for electron densities less than 10{sup 12 }cm{sup −2}. Therefore, h-BN should be an appealing substrate for graphene devices, as confirmed experimentally.

  10. Modelling substrate specificity and enantioselectivity for lipases and esterases by substrate-imprinted docking

    Directory of Open Access Journals (Sweden)

    Tyagi Sadhna

    2009-06-01

    Full Text Available Abstract Background Previously, ways to adapt docking programs that were developed for modelling inhibitor-receptor interaction have been explored. Two main issues were discussed. First, when trying to model catalysis a reaction intermediate of the substrate is expected to provide more valid information than the ground state of the substrate. Second, the incorporation of protein flexibility is essential for reliable predictions. Results Here we present a predictive and robust method to model substrate specificity and enantioselectivity of lipases and esterases that uses reaction intermediates and incorporates protein flexibility. Substrate-imprinted docking starts with covalent docking of reaction intermediates, followed by geometry optimisation of the resulting enzyme-substrate complex. After a second round of docking the same substrate into the geometry-optimised structures, productive poses are identified by geometric filter criteria and ranked by their docking scores. Substrate-imprinted docking was applied in order to model (i enantioselectivity of Candida antarctica lipase B and a W104A mutant, (ii enantioselectivity and substrate specificity of Candida rugosa lipase and Burkholderia cepacia lipase, and (iii substrate specificity of an acetyl- and a butyrylcholine esterase toward the substrates acetyl- and butyrylcholine. Conclusion The experimentally observed differences in selectivity and specificity of the enzymes were reproduced with an accuracy of 81%. The method was robust toward small differences in initial structures (different crystallisation conditions or a co-crystallised ligand, although large displacements of catalytic residues often resulted in substrate poses that did not pass the geometric filter criteria.

  11. Metallic coatings on silicon substrates, and methods of forming metallic coatings on silicon substrates

    Science.gov (United States)

    Branagan, Daniel J.; Hyde, Timothy A.; Fincke, James R.

    2008-03-11

    The invention includes methods of forming a metallic coating on a substrate which contains silicon. A metallic glass layer is formed over a silicon surface of the substrate. The invention includes methods of protecting a silicon substrate. The substrate is provided within a deposition chamber along with a deposition target. Material from the deposition target is deposited over at least a portion of the silicon substrate to form a protective layer or structure which contains metallic glass. The metallic glass comprises iron and one or more of B, Si, P and C. The invention includes structures which have a substrate containing silicon and a metallic layer over the substrate. The metallic layer contains less than or equal to about 2 weight % carbon and has a hardness of at least 9.2 GPa. The metallic layer can have an amorphous microstructure or can be devitrified to have a nanocrystalline microstructure.

  12. Synthesis and dephosphorylation of MARCKS in the late stages of megakaryocyte maturation drive proplatelet formation.

    Science.gov (United States)

    Machlus, Kellie R; Wu, Stephen K; Stumpo, Deborah J; Soussou, Thomas S; Paul, David S; Campbell, Robert A; Kalwa, Hermann; Michel, Thomas; Bergmeier, Wolfgang; Weyrich, Andrew S; Blackshear, Perry J; Hartwig, John H; Italiano, Joseph E

    2016-03-17

    Platelets are essential for hemostasis, and thrombocytopenia is a major clinical problem. Megakaryocytes (MKs) generate platelets by extending long processes, proplatelets, into sinusoidal blood vessels. However, very little is known about what regulates proplatelet formation. To uncover which proteins were dynamically changing during this process, we compared the proteome and transcriptome of round vs proplatelet-producing MKs by 2D difference gel electrophoresis (DIGE) and polysome profiling, respectively. Our data revealed a significant increase in a poorly-characterized MK protein, myristoylated alanine-rich C-kinase substrate (MARCKS), which was upregulated 3.4- and 5.7-fold in proplatelet-producing MKs in 2D DIGE and polysome profiling analyses, respectively. MARCKS is a protein kinase C (PKC) substrate that binds PIP2. In MKs, it localized to both the plasma and demarcation membranes. MARCKS inhibition by peptide significantly decreased proplatelet formation 53%. To examine the role of MARCKS in the PKC pathway, we treated MKs with polymethacrylate (PMA), which markedly increased MARCKS phosphorylation while significantly inhibiting proplatelet formation 84%, suggesting that MARCKS phosphorylation reduces proplatelet formation. We hypothesized that MARCKS phosphorylation promotes Arp2/3 phosphorylation, which subsequently downregulates proplatelet formation; both MARCKS and Arp2 were dephosphorylated in MKs making proplatelets, and Arp2 inhibition enhanced proplatelet formation. Finally, we used MARCKS knockout (KO) mice to probe the direct role of MARCKS in proplatelet formation; MARCKS KO MKs displayed significantly decreased proplatelet levels. MARCKS expression and signaling in primary MKs is a novel finding. We propose that MARCKS acts as a "molecular switch," binding to and regulating PIP2 signaling to regulate processes like proplatelet extension (microtubule-driven) vs proplatelet branching (Arp2/3 and actin polymerization-driven).

  13. Mass spectrometry-assisted protease substrate screening

    DEFF Research Database (Denmark)

    Schlüter, Hartmut; Rykl, Jana; Thiemann, Joachim;

    2007-01-01

    Since sequencing of the human genome was completed, more than 500 genes have been annotated as proteases. Exploring the physiological role of each protease requires the identification of their natural substrates. However, the endogenous substrates of many of the human proteases are as yet unknown....... Here we describe a new assay that addresses this problem. The assay, which easily can be automated, is based on the incubation of immobilized protein fractions, which may contain the natural substrate, with a defined protease. After concentrating the proteolytically released peptides by reversed...

  14. Study of Carbon Nanotube-Substrate Interaction

    Directory of Open Access Journals (Sweden)

    Jaqueline S. Soares

    2012-01-01

    Full Text Available Environmental effects are very important in nanoscience and nanotechnology. This work reviews the importance of the substrate in single-wall carbon nanotube properties. Contact with a substrate can modify the nanotube properties, and such interactions have been broadly studied as either a negative aspect or a solution for developing carbon nanotube-based nanotechnologies. This paper discusses both theoretical and experimental studies where the interaction between the carbon nanotubes and the substrate affects the structural, electronic, and vibrational properties of the tubes.

  15. Implantable biomedical devices on bioresorbable substrates

    Science.gov (United States)

    Rogers, John A; Kim, Dae-Hyeong; Omenetto, Fiorenzo; Kaplan, David L; Litt, Brian; Viventi, Jonathan; Huang, Yonggang; Amsden, Jason

    2014-03-04

    Provided herein are implantable biomedical devices, methods of administering implantable biomedical devices, methods of making implantable biomedical devices, and methods of using implantable biomedical devices to actuate a target tissue or sense a parameter associated with the target tissue in a biological environment. Each implantable biomedical device comprises a bioresorbable substrate, an electronic device having a plurality of inorganic semiconductor components supported by the bioresorbable substrate, and a barrier layer encapsulating at least a portion of the inorganic semiconductor components. Upon contact with a biological environment the bioresorbable substrate is at least partially resorbed, thereby establishing conformal contact between the implantable biomedical device and the target tissue in the biological environment.

  16. Biochemicalmethane potential (BMP) of solid organic substrates

    DEFF Research Database (Denmark)

    Raposo, F.; Fernández-Cegrí, V.; de la Rubia, M.A.

    2011-01-01

    BACKGROUND: This paper describes results obtained for different participating research groups in an interlaboratory study related to biochemical methane potential (BMP). In this research work, all experimental conditions influencing the test such as inoculum, substrate characteristics and experim...

  17. Iron films deposited on porous alumina substrates

    Science.gov (United States)

    Yamada, Yasuhiro; Tanabe, Kenichi; Nishida, Naoki; Kobayashi, Yoshio

    2016-12-01

    Iron films were deposited on porous alumina substrates using an arc plasma gun. The pore sizes (120 - 250 nm) of the substrates were controlled by changing the temperature during the anodic oxidation of aluminum plates. Iron atoms penetrated into pores with diameters of less than 160 nm, and were stabilized by forming γ-Fe, whereas α-Fe was produced as a flat plane covering the pores. For porous alumina substrates with pore sizes larger than 200 nm, the deposited iron films contained many defects and the resulting α-Fe had smaller hyperfine magnetic fields. In addition, only a very small amount of γ-Fe was obtained. It was demonstrated that the composition and structure of an iron film can be affected by the surface morphology of the porous alumina substrate on which the film is grown.

  18. Enhanced substrate conversion efficiency of fermentation processes

    OpenAIRE

    Sanders, J.P.M.; Weusthuis, R.A.; Mooibroek, H.

    2006-01-01

    The present invention relates to the field of fermentation technology. In particular the invention relates to fermentation processes for the production of a first and a second fermentation product by a single production organism wherein the first product is in a more reduced state than the substrate and the second fermentation product is in a more oxidised state than the substrate yet in less oxidised state than the final oxidation product CO2, such that the concurrent synthesis of the first ...

  19. Substrates and method for determining enzymes

    Science.gov (United States)

    Smith, Robert E.; Bissell, Eugene R.

    1981-01-01

    A method is disclosed for determining the presence of an enzyme in a biological fluid, which includes the steps of contacting the fluid with a synthetic chromogenic substrate, which is an amino acid derivative of 7-amino-4-trifluoromethylcoumarin; incubating the substrate-containing fluid to effect enzymatic hydrolysis; and fluorometrically determining the presence of the free 7-amino-4-trifluoromethylcoumarin chromophore in the hydrolyzate.

  20. Alternative substrates for higher mushrooms mycelia cultivation

    Directory of Open Access Journals (Sweden)

    TETIANA KRUPODOROVA

    2015-12-01

    Full Text Available Cultivation of 29 species of higher mushroom mycelia on alternative substrates – wastes of Ukrainian oil-fat industry, has been investigated. The amount of mushroom mycelia obtaining on 12 investigated substrates varied significantly, from 1.0 g/L to 22.9 g/L on the 14th day of cultivation. The superficial cultivation adopted in this study allows for easy to choose appropriate medium (substrate for mycelia production. Alternative substrates (compared to glucose-peptone-yeast medium were selected for all studied species, from soybean cake – most suitable for the mycelial growth of 24 species, to walnut cake − suitable only for 2 species. The utilization of substrates has been evaluated by biological efficiency. The best index of biological efficiency varied from 19.0% to 41.6% depending on the mushroom species. It was established high biological efficiency of mycelia cultivation on substrates: wheat seed cake – Pleurotus djamor, Lyophyllum shimeji, Crinipellis schevczenkovi, Phellinus igniarius, Spongipellis litschaueri; oat seed cake – Ganoderma applanatum and G. lucidum; soybean cake – Hohenbuehelia myxotricha, Trametes versicolor, Morchella esculenta, Cordyceps sinensis, C. militaris, and Agrocybe aegerita; rape seed cake – Auriporia aurea; camelina seed cake – Fomes fomentarius. The cultivation of these species are perspective as a biotechnological process of agricultural wastes converted into mycelia, which could be used in different forms of products with therapeutic action: powder or tablets nutraceuticals or ingredients for functional foods.

  1. Direct Printing of Graphene onto Plastic Substrates.

    Science.gov (United States)

    Hines, Daniel; Lock, Evgeniya; Walton, Scott; Baraket, Mira; Laskoski, Matthew; Mulvaney, Shawn; Sheehan, Paul; Lee, Woo; Robinson, Jeremy

    2011-03-01

    Graphene films have been synthesized on metal foils using CVD growth and have the potential to be compatible with roll-to-roll printing. To be usable in electronic devices, these films need to be removed from the metallic substrate. Currently this is accomplished by spin coating a polymer film over the graphene and chemically etching away the metal substrate. We have developed a direct printing method that allows graphene films to be printed off the metal substrate onto a polymer substrate. This printing process does not generate chemical waste, is compatible with roll-to-toll processing and renders the metal foil reusable. Adhesion of the graphene film to the polymer substrate is established by attaching perfluorophenylazides (PFPA) azide linker molecules to a plasma activated polymer surface. The transfer printing was performed by placing the PFPA treated polymer surface in contact with a graphene covered Cu foil and heating under pressure. Graphene films successfully printed onto a polystyrene substrate have been characterized by Raman spectroscopy and electrical measurements revealed the presence of Gr on the polymer surface. Details of the printing process along with characteristics of the graphene film after printing will be presented.

  2. Palladium clusters deposited on the heterogeneous substrates

    Science.gov (United States)

    Wang, Kun; Liu, Juanfang; Chen, Qinghua

    2016-07-01

    To improve the performance of the Pd composite membrane prepared by the cold spraying technology, it is extremely essential to give insights into the deposition process of the cluster and the heterogeneous deposition of the big Pd cluster at the different incident velocities on the atomic level. The deposition behavior, morphologies, energetic and interfacial configuration were examined by the molecular dynamic simulation and characterized by the cluster flattening ratio, the substrate maximum local temperature, the atom-embedded layer number and the surface-alloy formation. According to the morphology evolution, three deposition stages and the corresponding structural and energy evolution were clearly identified. The cluster deformation and penetrating depth increased with the enhancement of the incident velocity, but the increase degree also depended on the substrate hardness. The interfacial interaction between the cluster and the substrate can be improved by the higher substrate local temperature. Furthermore, it is found that the surface alloys were formed by exchanging sites between the cluster and substrate atoms, and the cluster atoms rearranged following as the substrate lattice arrangement from bottom to up in the deposition course. The ability and scope of the structural reconstruction are largely determined by both the size and incident energy of the impacted cluster.

  3. Spectrophotometric determination of substrate-borne polyacrylamide.

    Science.gov (United States)

    Lu, Jianhang; Wu, Laosheng

    2002-08-28

    Polyacrylamides (PAMs) have wide application in many industries and in agriculture. Scientific research and industrial applications manifested a need for a method that can quantify substrate-borne PAM. The N-bromination method (a PAM analytical technique based on N-bromination of amide groups and spectrophotometric determination of the formed starch-triiodide complex), which was originally developed for determining PAM in aqueous solutions, was modified to quantify substrate-borne PAM. In the modified method, the quantity of substrate-borne PAM was converted to a concentration of starch-triiodide complex in aqueous solution that was then measured by spectrophotometry. The method sensitivity varied with substrates due to sorption of reagents and reaction intermediates on the substrates. Therefore, separate calibration for each substrate was required. Results from PAM samples in sand, cellulose, organic matter burnt soils, and clay minerals showed that this method had good accuracy and reproducibility. The PAM recoveries ranged from 95.8% to 103.7%, and the relative standard deviations (n = 4) were <7.5% in all cases. The optimum range of PAM in each sample is 10-80 microg. The technique can serve as an effective tool in improving PAM application and facilitating PAM-related research.

  4. Nanomechanics of hard films on compliant substrates.

    Energy Technology Data Exchange (ETDEWEB)

    Reedy, Earl David, Jr. (Sandia National Laboratories, Albuquerque, NM); Emerson, John Allen (Sandia National Laboratories, Albuquerque, NM); Bahr, David F. (Washington State University, Pullman, WA); Moody, Neville Reid; Zhou, Xiao Wang; Hales, Lucas (University of Minnesota, Minneapolis, MN); Adams, David Price (Sandia National Laboratories, Albuquerque, NM); Yeager,John (Washington State University, Pullman, WA); Nyugen, Thao D. (Johns Hopkins University, Baltimore, MD); Corona, Edmundo (Sandia National Laboratories, Albuquerque, NM); Kennedy, Marian S. (Clemson University, Clemson, SC); Cordill, Megan J. (Erich Schmid Institute, Leoben, Austria)

    2009-09-01

    Development of flexible thin film systems for biomedical, homeland security and environmental sensing applications has increased dramatically in recent years [1,2,3,4]. These systems typically combine traditional semiconductor technology with new flexible substrates, allowing for both the high electron mobility of semiconductors and the flexibility of polymers. The devices have the ability to be easily integrated into components and show promise for advanced design concepts, ranging from innovative microelectronics to MEMS and NEMS devices. These devices often contain layers of thin polymer, ceramic and metallic films where differing properties can lead to large residual stresses [5]. As long as the films remain substrate-bonded, they may deform far beyond their freestanding counterpart. Once debonded, substrate constraint disappears leading to film failure where compressive stresses can lead to wrinkling, delamination, and buckling [6,7,8] while tensile stresses can lead to film fracture and decohesion [9,10,11]. In all cases, performance depends on film adhesion. Experimentally it is difficult to measure adhesion. It is often studied using tape [12], pull off [13,14,15], and peel tests [16,17]. More recent techniques for measuring adhesion include scratch testing [18,19,20,21], four point bending [22,23,24], indentation [25,26,27], spontaneous blisters [28,29] and stressed overlayers [7,26,30,31,32,33]. Nevertheless, sample design and test techniques must be tailored for each system. There is a large body of elastic thin film fracture and elastic contact mechanics solutions for elastic films on rigid substrates in the published literature [5,7,34,35,36]. More recent work has extended these solutions to films on compliant substrates and show that increasing compliance markedly changes fracture energies compared with rigid elastic solution results [37,38]. However, the introduction of inelastic substrate response significantly complicates the problem [10,39,40]. As

  5. Substrate specificity in enzymatic fluorination. The fluorinase from Streptomyces cattleya accepts 2'-deoxyadenosine substrates.

    Science.gov (United States)

    Cobb, Steven L; Deng, Hai; McEwan, Andrew R; Naismith, James H; O'Hagan, David; Robinson, David A

    2006-04-21

    The fluorinase enzyme from Streptomyces cattleya displays an unusual ability in biocatalysis in that it forms a C-F bond. We now report that the enzyme will accept 2'-deoxyadenosine in place of adenosine substrates, and structural evidence reveals a reorganisation in hydrogen bonding to accommodate this substrate series. It emerges from this study that the enzyme does not require a planar ribose conformation of the substrate to catalyse C-F bond formation.

  6. Colloidal Drop Deposition on Porous Substrates

    Science.gov (United States)

    Sun, Ying; Pack, Min; Hu, Han; Kim, Dong-Ook; Yang, Xin

    2015-11-01

    Printable electronics and in particular paper and textile-based electronics have fueled research in inkjet printing on porous substrates. On nonporous substrates, the particle motion of the particles and evaporation of the solvent are the two main mechanisms that drive the final deposition morphology. For porous substrates another factor, mainly infiltration, adds a layer of complexity to the deposition patterns that has not yet been elucidated in literature. In this study, a high-speed camera was used to capture the imbibition of picoliter-sized polystyrene nanoparticles in water droplets into nano-porous anodic aluminum oxide substrates of various porosities and wettabilities. For water, the infiltration rate is much faster than both evaporation and particle motion and thus when the substrate fully imbibes the droplet, the well-known ``coffee ring'' is suppressed. However, when a residual droplet forms upon the termination of the infiltration regime, the competing particle motion and evaporation regimes, tP and tEI respectively, define the critical time scales for which the coffee ring will be formed (tP /tEI 1). National Science Foundation under Grant No. CMMI-1401438.

  7. Molecular cloning and expression analysis of receptor for activated C kinase 1 (HcRACK1) from Hyriopsis cumingii%三角帆蚌活化蛋白激酶C受体1基因(HcRACK1)的克隆及表达分析

    Institute of Scientific and Technical Information of China (English)

    王俊南; 汪桂玲; 白志毅; 李家乐

    2016-01-01

    为了探究RACK1基因在三角帆蚌免疫系统中的调控机制,采用RACE技术克隆得到三角帆蚌RACK1基因(命名为HcRACK1)的cDNA全序列,并对该序列进行分析.结果显示,HcRA CK1基因全长为1249 bp,其中开放阅读框957 bp,编码318个氨基酸.蛋白质结构域分析显示HcRACK1含有RACK1家族特有的7个WD40结构域.运用荧光定量PCR技术分析HcRA CK1在正常组织中及受到嗜水气单胞菌侵染和重金属镉暴露后相关组织表达量的变化.结果显示,HcRACK1在各个组织中均有表达,其中闭壳肌中表达量最高;嗜水气单胞菌侵染后,HcRACK1在血淋巴中的表达量逐渐上升,24 h时达到峰值,随后下降;暴露在100 μg/L浓度的重金属镉中,HcRACK1在肝胰腺中的表达量逐渐上升,在第3天达到峰值;血淋巴在第2天达到峰值,随后下降;鳃中HcRAC K1的表达量无明显变化.上述结果表明,HcRAC K1与细菌及镉引起的机体的氧化应激反应有关,并能参与到机体的免疫反应中.%In the present study,full length cDNA sequence of receptor for activated C kinase 1 gene of Hyriopsis cumingii(HcRACK1) was cloned by using 3'RACE and 5'RACE techniques,and the sequence and structural analysis of the HcRACK1 gene was conducted by using bioinformatics method.The results showed that the full-length cDNA of HcRACK1 consisted of 1249 bp in length,containing an open reading frame (ORF) of 957 bp encoding 318 amino acids.Analysis of protein domain features showed that the deduced polypeptide contained seven WD40 domains characteristic of RACK1 protein family.The tissue distribution of HcRACK1 in unchallenged H.cumingii and temporal expression pattern of HcRACK1 challenged with bacteria and exposed to 100 μg/L cadmium were analyzed by quantitative real-time PCR (qRT-PCR).The transcript was detected in all tissues tested,and the expression level was the highest in adductor muscle.After challenge with bacteria,expression level of HcRACK1 in haemocytes

  8. Substrate recognition by ribonucleoprotein ribonuclease MRP.

    Science.gov (United States)

    Esakova, Olga; Perederina, Anna; Quan, Chao; Berezin, Igor; Krasilnikov, Andrey S

    2011-02-01

    The ribonucleoprotein complex ribonuclease (RNase) MRP is a site-specific endoribonuclease essential for the survival of the eukaryotic cell. RNase MRP closely resembles RNase P (a universal endoribonuclease responsible for the maturation of the 5' ends of tRNA) but recognizes distinct substrates including pre-rRNA and mRNA. Here we report the results of an in vitro selection of Saccharomyces cerevisiae RNase MRP substrates starting from a pool of random sequences. The results indicate that RNase MRP cleaves single-stranded RNA and is sensitive to sequences in the immediate vicinity of the cleavage site requiring a cytosine at the position +4 relative to the cleavage site. Structural implications of the differences in substrate recognition by RNases P and MRP are discussed.

  9. Thermal Oxidation of Silicon Carbide Substrates

    Institute of Scientific and Technical Information of China (English)

    Xiufang Chen; Li'na Ning; Yingmin Wang; Juan Li; Xiangang Xu; Xiaobo Hu; Minhua Jiang

    2009-01-01

    Thermal oxidation was used to remove the subsurface damage of silicon carbide (SiC) surfaces. The anisotrow of oxidation and the composition of oxide layers on Si and C faces were analyzed. Regular pits were observed on the surface after the removal of the oxide layers, which were detrimental to the growth of high quality epitaxial layers. The thickness and composition of the oxide layers were characterized by Rutherford backscat-tering spectrometry (RBS) and X-ray photoelectron spectroscopy (XPS), respectively. Epitaxial growth was performed in a metal organic chemical vapor deposition (MOCVD) system. The substrate surface morphol-ogy after removing the oxide layer and gallium nitride (GaN) epilayer surface were observed by atomic force microscopy (AFM). The results showed that the GaN epilayer grown on the oxidized substrates was superior to that on the unoxidized substrates.

  10. Methods of selectively incorporating metals onto substrates

    Energy Technology Data Exchange (ETDEWEB)

    Ernst; Richard D. (Salt Lake City, UT), Eyring; Edward M. (Salt Lake City, UT), Turpin; Gregory C. (Salt Lake City, UT), Dunn; Brian C. (Salt Lake City, UT)

    2008-09-30

    A method for forming multi-metallic sites on a substrate is disclosed and described. A substrate including active groups such as hydroxyl can be reacted with a pretarget metal complex. The target metal attached to the active group can then be reacted with a secondary metal complex such that an oxidation-reduction (redox) reaction occurs to form a multi-metallic species. The substrate can be a highly porous material such as aerogels, xerogels, zeolites, and similar materials. Additional metal complexes can be reacted to increase catalyst loading or control co-catalyst content. The resulting compounds can be oxidized to form oxides or reduced to form metals in the ground state which are suitable for practical use.

  11. Plasma jet printing for flexible substrates

    Science.gov (United States)

    Gandhiraman, Ram P.; Singh, Eric; Diaz-Cartagena, Diana C.; Nordlund, Dennis; Koehne, Jessica; Meyyappan, M.

    2016-03-01

    Recent interest in flexible electronics and wearable devices has created a demand for fast and highly repeatable printing processes suitable for device manufacturing. Robust printing technology is critical for the integration of sensors and other devices on flexible substrates such as paper and textile. An atmospheric pressure plasma-based printing process has been developed to deposit different types of nanomaterials on flexible substrates. Multiwalled carbon nanotubes were deposited on paper to demonstrate site-selective deposition as well as direct printing without any type of patterning. Plasma-printed nanotubes were compared with non-plasma-printed samples under similar gas flow and other experimental conditions and found to be denser with higher conductivity. The utility of the nanotubes on the paper substrate as a biosensor and chemical sensor was demonstrated by the detection of dopamine, a neurotransmitter, and ammonia, respectively.

  12. Pentamines as substrate for human spermine oxidase

    Science.gov (United States)

    Takao, Koichi; Shirahata, Akira; Samejima, Keijiro; Casero, Robert A.; Igarashi, Kazuei; Sugita, Yoshiaki

    2013-01-01

    Substrate activities of various linear polyamines to human spermine oxidase (hSMO) were investigated. The activities were evaluated by monitoring the amount of H2O2 released from sample polyamines by hSMO. H2O2 was measured by a HPLC method that analyzed fluorescent dimers derived from the oxidation of homovanillic acid in the presence of horseradish peroxidase. Six triamines were tested and were found not to be hSMO substrates. Of sixteen tetramines tested, spermine (Spm) was the most active substrate, followed by homospermine and N-butylated Spm. Pentamines showed a characteristic pattern of substrate activity. Of thirteen pentamines tested, 3343 showed higher substrate activity than Spm, and 4343 showed similar activity to Spm. The activities of the other pentamines were as follows: 3443, 4443, 4344, 3344, 4334, 4444, and 3334 (in decreasing order). Product amines released from these pentamines by hSMO were then analyzed by HPLC. Triamine was the only observed product, and the amount of triamine was nearly equivalent to that of released H2O2. A marked difference in the pH dependency curves between tetramines and pentamines suggested that hSMO favored reactions with a non-protonated secondary nitrogen at the cleavage site. The Km and Vmax values for Spm and 3343 at pH 7.0 and 9.0 were consistent with the higher substrate activity of 3343 compared to Spm, as well as with the concept of a non-protonated secondary nitrogen at the cleavage site being preferred, and 3343 was well degraded at a physiological pH by hSMO. PMID:23449327

  13. Direct-Cooled Power Electronics Substrate

    Energy Technology Data Exchange (ETDEWEB)

    Wiles, R.; Ayers, C.; Wereszczak, A.

    2008-12-23

    The goal of the Direct-Cooled Power Electronics Substrate project is to reduce the size and weight of the heat sink for power electronics used in hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs). The concept proposed in this project was to develop an innovative power electronics mounting structure, model it, and perform both thermal and mechanical finite-element analysis (FEA). This concept involved integrating cooling channels within the direct-bonded copper (DBC) substrate and strategically locating these channels underneath the power electronic devices. This arrangement would then be directly cooled by water-ethylene glycol (WEG), essentially eliminating the conventional heat sink and associated heat flow path. The concept was evaluated to determine its manufacturability, its compatibility with WEG, and the potential to reduce size and weight while directly cooling the DBC and associated electronics with a coolant temperature of 105 C. This concept does not provide direct cooling to the electronics, only direct cooling inside the DBC substrate itself. These designs will take into account issues such as containment of the fluid (separation from the electronics) and synergy with the whole power inverter design architecture. In FY 2008, mechanical modeling of substrate and inverter core designs as well as thermal and mechanical stress FEA modeling of the substrate designs was performed, along with research into manufacturing capabilities and methods that will support the substrate designs. In FY 2009, a preferred design(s) will be fabricated and laboratory validation testing will be completed. In FY 2010, based on the previous years laboratory testing, the mechanical design will be modified and the next generation will be built and tested in an operating inverter prototype.

  14. Substrates for clinical applicability of stem cells

    Institute of Scientific and Technical Information of China (English)

    Sanjar Enam; Sha Jin

    2015-01-01

    The capability of human pluripotent stem cells (hPSCs)to differentiate into a variety of cells in the human bodyholds great promise for regenerative medicine. Manysubstrates exist on which hPSCs can be self-renewed,maintained and expanded to further the goal of clinicalapplication of stem cells. In this review, we highlightnumerous extracellular matrix proteins, peptide andpolymer based substrates, scaffolds and hydrogelsthat have been pioneered. We discuss their benefitsand shortcomings and offer future directions as well asemphasize commercially available synthetic peptidesas a type of substrate that can bring the benefits ofregenerative medicine to clinical settings.

  15. Method for Producing Substrates for Superconducting Layers

    DEFF Research Database (Denmark)

    2015-01-01

    There is provided a method for producing a substrate suitable for supporting an elongated superconducting element, wherein one or more elongated strips of masking material are placed on a solid element (202) so as to form one or more exposed elongated areas being delimited on one or two sides...... the portion of filling material and the solid element. The method may further comprise placing buffer material (640) and or superconducting material (642, 644, 646)) on the substrate, so as to provide a superconducting structure (601) with reduced AC losses....

  16. Flexible, light trapping substrates for organic photovoltaics

    Science.gov (United States)

    Park, Yoonseok; Berger, Jana; Tang, Zheng; Müller-Meskamp, Lars; Lasagni, Andrés Fabián; Vandewal, Koen; Leo, Karl

    2016-08-01

    Micro-structured organic photovoltaic (OPV) devices on polyethylene terephthalate substrates are produced using direct laser interference patterning (DLIP). The performance of organic solar cells on these substrates is improved by a factor of 1.16, and a power conversion efficiency of 7.70% is achieved. We show that a shorter spatial period of the pattern allows for a stronger light trapping effect in solar cell, as it leads to a longer light path. Moreover, since the patterned structures are located on the outside of the fully encapsulated OPV devices, there are no problems with the roughness induced shunts.

  17. High alcohol production by solid substrate fermentation from starchy substrates using thermotolerant Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Sree, N.K.; Sridhar, M.; Suresh, K.; Rao, L.V. [Department of Microbiology, Osmania University, Hyderabad 500007, Andhra Pradesh (India)

    1999-06-01

    Solid Substrate Fermentation system (SSF) was used to produce ethanol from various starchy substrates like sweet sorghum, sweet potato, wheat flour, rice starch, soluble starch and potato starch using thermotolerant yeast isolate (VS{sub 3}) by simultaneous saccharification and fermentation process. Alcohol produced was estimated by gas chromatography after an incubation time of 96 hrs at 37 C and 42 C. More ethanol was produced from rice starch and sweet sorghum. The maximum amount of ethanol produced from these substrates using VS{sub 3} was 10 g/100 g and 3.5 g/100 g substrate (rice starch) and 8.2 g and 7.5 g/100 g substrate (sweet sorghum) at 37 C and 42 C respectively. (orig.) With 2 figs., 1 tab., 12 refs.

  18. Substrate quality alters the microbial mineralization of added substrate and soil organic carbon

    Science.gov (United States)

    Jagadamma, S.; Mayes, M. A.; Steinweg, J. M.; Schaeffer, S. M.

    2014-09-01

    The rate and extent of decomposition of soil organic carbon (SOC) is dependent, among other factors, on substrate chemistry and microbial dynamics. Our objectives were to understand the influence of substrate chemistry on microbial decomposition of carbon (C), and to use model fitting to quantify differences in pool sizes and mineralization rates. We conducted an incubation experiment for 270 days using four uniformly labeled 14C substrates (glucose, starch, cinnamic acid and stearic acid) on four different soils (a temperate Mollisol, a tropical Ultisol, a sub-arctic Andisol, and an arctic Gelisol). The 14C labeling enabled us to separate CO2 respired from added substrates and from native SOC. Microbial gene copy numbers were quantified at days 4, 30 and 270 using quantitative polymerase chain reaction (qPCR). Substrate C respiration was always higher for glucose than other substrates. Soils with cinnamic and stearic acid lost more native SOC than glucose- and starch-amended soils. Cinnamic and stearic acid amendments also exhibited higher fungal gene copy numbers at the end of incubation compared to unamended soils. We found that 270 days were sufficient to model the decomposition of simple substrates (glucose and starch) with three pools, but were insufficient for more complex substrates (cinnamic and stearic acid) and native SOC. This study reveals that substrate quality exerts considerable control on the microbial decomposition of newly added and native SOC, and demonstrates the need for multi-year incubation experiments to constrain decomposition parameters for the most recalcitrant fractions of SOC and complex substrates.

  19. Spreading of liquid drops over porous substrates.

    Science.gov (United States)

    Starov, V M; Zhdanov, S A; Kosvintsev, S R; Sobolev, V D; Velarde, M G

    2003-07-01

    The spreading of small liquid drops over thin and thick porous layers (dry or saturated with the same liquid) has been investigated in the case of both complete wetting (silicone oils of different viscosities) and partial wetting (aqueous SDS solutions of different concentrations). Nitrocellulose membranes of different porosity and different average pore size have been used as a model of thin porous layers, glass and metal filters have been used as a model of thick porous substrates. The first problem under investigation has been the spreading of small liquid drops over thin porous layers saturated with the same liquid. An evolution equation describing the drop spreading has been deduced, which showed that both an effective lubrication and the liquid exchange between the drop and the porous substrates are equally important. Spreading of silicone oils over different nitrocellulose microfiltration membranes was carried out. The experimental laws of the radius of spreading on time confirmed the theory predictions. The spreading of small liquid drops over thin dry porous layers has also been investigated from both theoretical and experimental points of view. The drop motion over a dry porous layer appears caused by the interplay of two processes: (a). the spreading of the drop over already saturated parts of the porous layer, which results in a growth of the drop base, and (b). the imbibition of the liquid from the drop into the porous substrate, which results in a shrinkage of the drop base and a growth of the wetted region inside the porous layer. As a result of these two competing processes the radius of the drop base goes through a maximum as time proceeds. A system of two differential equations has been derived to describe the time evolution of the radii of both the drop base and the wetted region inside the porous layer. This system includes two parameters, one accounts for the effective lubrication coefficient of the liquid over the wetted porous substrate, and

  20. MIXED SUBSTRATES IN ENVIRONMENT AND BIOTECHNOLOGICAL PROCESSES

    Directory of Open Access Journals (Sweden)

    T. P. Pirog

    2013-12-01

    Full Text Available The modern literature and own experimental data on the use of substrates’ mixtures for intensification of microbial synthesis technologies of practically valuable fermentation products (ethanol, lactic acid, butanediol, primary (amino acids, n-hydroxybenzoate, triglycerides and secondary (lovastatin, surfactants metabolites as well as for intensification of biodegradation of aromatic xenobiotics (benzene, cresols, phenols, toluene and pesticides (dimethoate are presented. Special attention is paid on the molecular mechanisms that were established in recent years and underlying the phenomenon catabolic repression in Gram-positive (Bacillus subtilis and Gram-negative (Pseudomonas, Escherichia coli bacteria and yeast Saccharomyces cerevisiae, and on the use of these data to develop technologies for utilization of plant biomass to produce industrially important metabolites. The survival strategies of heterotrophic microorganisms in natural oligotrophic environments are considered, including the simultaneous use of multiple substrates, allowing improved kinetic characteristics that give them a competitive advantage, also provided significant metabolic/physiological flexibility. The own experimental data on the use of mixtures of growth substrates for the intensification of surfactants’ synthesis of Rhodococcus erythropolis IMV Ac-5017 and Acinetobacter calcoaceticus IMV B-7241 are summarized. The dependence of the synthesis of surfactants in a mixture of energy excess (hexadecane and energy deficient (glycerol, ethanol substrates on the way of inoculum preparation, concentration of mono-substrates in the mixture, and their molar ratio were determined.

  1. Buckling Behavior of Substrate Supported Graphene Sheets

    Directory of Open Access Journals (Sweden)

    Kuijian Yang

    2016-01-01

    Full Text Available The buckling of graphene sheets on substrates can significantly degrade their performance in materials and devices. Therefore, a systematic investigation on the buckling behavior of monolayer graphene sheet/substrate systems is carried out in this paper by both molecular mechanics simulations and theoretical analysis. From 70 simulation cases of simple-supported graphene sheets with different sizes under uniaxial compression, two different buckling modes are investigated and revealed to be dominated by the graphene size. Especially, for graphene sheets with length larger than 3 nm and width larger than 1.1 nm, the buckling mode depends only on the length/width ratio. Besides, it is revealed that the existence of graphene substrate can increase the critical buckling stress and strain to 4.39 N/m and 1.58%, respectively, which are about 10 times those for free-standing graphene sheets. Moreover, for graphene sheets with common size (longer than 20 nm, both theoretical and simulation results show that the critical buckling stress and strain are dominated only by the adhesive interactions with substrate and independent of the graphene size. Results in this work provide valuable insight and guidelines for the design and application of graphene-derived materials and nano-electromechanical systems.

  2. Biofunctional Micropatterning of Thermoformed 3D Substrates

    NARCIS (Netherlands)

    Waterkotte, B.; Bally, F.; Nikolov, P.M.; Waldbaur, A.; Rapp, B.E.; Truckenmuller, R.K.; Lahann, J.; Schmitz, K.; Giselbrecht, S.

    2014-01-01

    Mimicking the in vivo microenvironment of cells is a challenging task in engineering in vitro cell models. Surface functionalization is one of the key components providing biochemical cues to regulate the interaction between cells and their substrate. In this study, two different approaches yield bi

  3. Drying of Pigment-Cellulose Nanofibril Substrates

    Directory of Open Access Journals (Sweden)

    Oleg Timofeev

    2014-10-01

    Full Text Available A new substrate containing cellulose nanofibrils and inorganic pigment particles has been developed for printed electronics applications. The studied composite structure contains 80% fillers and is mechanically stable and flexible. Before drying, the solids content can be as low as 20% due to the high water binding capacity of the cellulose nanofibrils. We have studied several drying methods and their effects on the substrate properties. The aim is to achieve a tight, smooth surface keeping the drying efficiency simultaneously at a high level. The methods studied include: (1 drying on a hot metal surface; (2 air impingement drying; and (3 hot pressing. Somewhat surprisingly, drying rates measured for the pigment-cellulose nanofibril substrates were quite similar to those for the reference board sheets. Very high dewatering rates were observed for the hot pressing at high moisture contents. The drying method had significant effects on the final substrate properties, especially on short-range surface smoothness. The best smoothness was obtained with a combination of impingement and contact drying. The mechanical properties of the sheets were also affected by the drying method and associated temperature.

  4. Bicarbonate is a recycling substrate for cyanase

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, W.V.; Anderson, P.M.

    1987-05-01

    Cyanase catalyzes HCO/sub 3//sup -/-dependent decomposition of cyanate to NH/sub 4//sup +/ and HCO/sub 3//sup -/. Previous studies provided evidence that carbamate is an initial product and that the kinetic mechanism is rapid equilibrium random (HCO/sub 3//sup -/ serving as substrate as opposed to activator). Direct evidence for this mechanism was obtained in this study by (1) identifying the products formed from (/sup 14/C)HCO/sub 3//sup -/ or (/sup 14/C)OCN/sup -/, (2) identifying the products formed from (/sup 13/C)HCO/sub 3//sup -/ in the presence of (/sup 18/O)H/sub 2/O, and (3) determining whether CO/sub 2/ or HCO/sub 3//sup -/ serve as substrate and are formed as product. Carbon dioxide (not HCO/sub 3//sup -/) is produced in stoichiometric amounts from both HCO/sub 3//sup -/ and OCN/sup -/. Bicarbonate (not CO/sub 2/) is the substrate. Oxygen-18 from (/sup 18/O)H/sub 2/O is not incorporated into CO/sub 2/ formed from either HCO/sub 3//sup -/ or OCN/sup -/. These results indicate that decomposition of cyanate is not a hydrolysis reaction and that HCO/sub 3//sup -/ functions as a substrate.

  5. Bicarbonate is a recycling substrate for cyanase.

    Science.gov (United States)

    Johnson, W V; Anderson, P M

    1987-07-01

    Cyanase is an inducible enzyme in Escherichia coli that catalyzes bicarbonate-dependent decomposition of cyanate to ammonia and bicarbonate. Previous studies provided evidence that carbamate is an initial product and that the kinetic mechanism is rapid equilibrium random (bicarbonate serving as substrate as opposed to activator); the following mechanism was proposed (Anderson, P. M. (1980) Biochemistry 19, 2282-2888; Anderson, P. M., and Little, R. M. (1986) Biochemistry 25, 1621-1626). (formula; see text) Direct evidence for this mechanism was obtained in this study by 1) determining whether CO2 or HCO3- serves as substrate and is formed as product, 2) identifying the products formed from [14C]HCO3- and [14C] OCN-, 3) identifying the products formed from [13C] HCO3- and [12C]OCN- in the presence of [18O]H2O, and 4) determining whether 18O from [18O]HCO3- is incorporated into CO2 derived from OCN-. Bicarbonate (not CO2) is the substrate. Carbon dioxide (not HCO3-) is produced in stoichiometric amounts from both HCO3- and OCN-. 18O from [18O]H2O is not incorporated into CO2 formed from either HCO3- or OCN-. Oxygen-18 from [18O]HCO3- is incorporated into CO2 derived from OCN-. These results support the above mechanism, indicating that decomposition of cyanate catalyzed by cyanase is not a hydrolysis reaction and that bicarbonate functions as a recycling substrate.

  6. Robust fabric substrates for photonic textile applications

    NARCIS (Netherlands)

    Van Pieterson, L.; Bouten, P.C.P.; Kriege, J.C.; Bhattacharya, R.

    2010-01-01

    A fabric substrate is described for electronic textile with robust interwoven connections between the conductive yarns in it. The fabric's robustness, as a function of the electrical reliability of its conductive yarn connections, is shown to hold over large deformations.This fabric is then used to

  7. Instabilities of soft films on compliant substrates

    Science.gov (United States)

    Holland, M. A.; Li, B.; Feng, X. Q.; Kuhl, E.

    2017-01-01

    Instabilities in bilayered systems can generate a wide variety of patterns ranging from simple folds, wrinkles, and creases to complex checkerboards, hexagons, and herringbones. Physics-based theories traditionally model these systems as a thin film on a thick substrate under confined compression and assume that the film is orders of magnitude stiffer than the substrate. However, instability phenomena in soft films on soft substrates remain insufficiently understood. Here we show that soft bilayered systems are highly sensitive to the stiffness ratio, boundary conditions, and mode of compression. In a systematic analysis over a wide range of stiffness ratios, from 0.1 domain compression, substrate prestretch, and film growth, we observe significantly different instability characteristics in the low-stiffness-contrast regime, for β domain compression are unstable for a wide range of wrinkling modes, under film-only compression, the same systems display distinct wrinkling modes.Strikingly, these discrepancies disappear when using measures of effective strain, effective stiffness, and effective wavelength. Our study suggests that future instability studies should use these effective measures to standardize their findings. Our results have important applications in soft matter and living matter physics, where stiffness contrasts are low and small environmental changes can have large effects on morphogenesis, pattern tabselection, and the evolution of shape.

  8. Cathodoluminescence Microscopy of nanostructures on glass substrates

    NARCIS (Netherlands)

    Narvaez, A.C.; Weppelman, I.G.C.; Moerland, R.J.; Liv, N.; Zonnevylle, A.C.; Kruit, P.; Hoogenboom, J.P.

    2013-01-01

    Cathodoluminescence (CL) microscopy is an emerging analysis technique in the fields of biology and photonics, where it is used for the characterization of nanometer sized structures. For these applications, the use of transparent substrates might be highly preferred, but the detection of CL from nan

  9. Potential of enzymatic kinetic resolution using solid substrates suspension: improved yield, productivity, substrate concentration, and recovery

    Science.gov (United States)

    Wolff; van Asperen V; Straathof; Heijnen

    1999-03-01

    In the literature the enzymatic kinetic resolution of a suspension of a solid substrate has largely been treated as a conventional kinetic resolution of a fully dissolved substrate. In this paper it is shown that this type of kinetic resolution is different in several important aspects. Quantitative models are developed for two types of such suspension processes. These models are used to compare the merits of these processes with the conventional kinetic resolution process where fully dissolved substrate is used. In the suspension processes the liquid phase concentration of substrate enantiomer that should be converted can be kept close to the maximum value, i.e., the solubility, when process conditions are properly chosen, whereas in a conventional process this concentration gradually decreases. Calculations show that this leads to a productivity that is about 6-fold higher in the suspension processes. Also, for enzymes with a low enantioselectivity, a severalfold increase in yield of remaining enantiopure substrate is predicted compared to the conventional kinetic resolution of dissolved enantiomers. Other potential advantages of using suspension reactions are that the initial substrate concentration may be higher (up to 25% (w/w)) and that the desired remaining substrate may be recovered by simply filtering off the solid crystals. Experimental evidence that these merits can be exploited is only partly given, using the few available examples from the literature.

  10. Silvering substrates after CO2 snow cleaning

    Science.gov (United States)

    Zito, Richard R.

    2005-09-01

    There have been some questions in the astronomical community concerning the quality of silver coatings deposited on substrates that have been cleaned with carbon dioxide snow. These questions center around the possible existence of carbonate ions left behind on the substrate by CO2. Such carbonate ions could react with deposited silver to produce insoluble silver carbonate, thereby reducing film adhesion and reflectivity. Carbonate ions could be produced from CO2 via the following mechanism. First, during CO2 snow cleaning, a small amount of moisture can condense on a surface. This is especially true if the jet of CO2 is allowed to dwell on one spot. CO2 gas can dissolve in this moisture, producing carbonic acid, which can undergo two acid dissociations to form carbonate ions. In reality, it is highly unlikely that charged carbonate ions will remain stable on a substrate for very long. As condensed water evaporates, Le Chatelier's principle will shift the equilibrium of the chain of reactions that produced carbonate back to CO2 gas. Furthermore, the hydration of CO2 reaction of CO2 with H20) is an extremely slow process, and the total dehydrogenation of carbonic acid is not favored. Living tissues that must carry out the equilibration of carbonic acid and CO2 use the enzyme carbonic anhydrase to speed up the reaction by a factor of one million. But no such enzymatic action is present on a clean mirror substrate. In short, the worst case analysis presented below shows that the ratio of silver atoms to carbonate radicals must be at least 500 million to one. The results of chemical tests presented here support this view. Furthermore, film lift-off tests, also presented in this report, show that silver film adhesion to fused silica substrates is actually enhanced by CO2 snow cleaning.

  11. Multifunctional epitaxial systems on silicon substrates

    Science.gov (United States)

    Singamaneni, Srinivasa Rao; Prater, John Thomas; Narayan, Jagdish

    2016-09-01

    Multifunctional heterostructures can exhibit a wide range of functional properties, including colossal magneto-resistance, magnetocaloric, and multiferroic behavior, and can display interesting physical phenomena including spin and charge ordering and strong spin-orbit coupling. However, putting this functionality to work remains a challenge. To date, most of the work reported in the literature has dealt with heterostructures deposited onto closely lattice matched insulating substrates such as DyScO3, SrTiO3 (STO), or STO buffered Si(100) using concepts of lattice matching epitaxy (LME). However, strain in heterostructures grown by LME is typically not fully relaxed and the layers contain detrimental defects such as threading dislocations that can significantly degrade the physical properties of the films and adversely affect the device characteristics. In addition, most of the substrates are incompatible with existing CMOS-based technology, where Si (100) substrates dominate. This review discusses recent advances in the integration of multifunctional oxide and non-oxide materials onto silicon substrates. An alternative thin film growth approach, called "domain matching epitaxy," is presented which identifies approaches for minimizing lattice strain and unwanted defects in large misfit systems (7%-25% and higher). This approach broadly allows for the integration of multifunctional materials onto silicon substrates, such that sensing, computation, and response functions can be combined to produce next generation "smart" devices. In general, pulsed laser deposition has been used to epitaxially grow these materials, although the concepts developed here can be extended to other deposition techniques, as well. It will be shown that TiN and yttria-stabilized zirconia template layers provide promising platforms for the integration of new functionality into silicon-based computer chips. This review paper reports on a number of thin-film heterostructure systems that span a

  12. Self-Assembled Local Artificial Substrates of GaAs on Si Substrate

    Directory of Open Access Journals (Sweden)

    Frigeri C

    2010-01-01

    Full Text Available Abstract We propose a self-assembling procedure for the fabrication of GaAs islands by Droplet Epitaxy on silicon substrate. Controlling substrate temperature and amount of supplied gallium is possible to tune the base size of the islands from 70 up to 250 nm and the density from 107 to 109 cm−2. The islands show a standard deviation of base size distribution below 10% and their shape evolves changing the aspect ratio from 0.3 to 0.5 as size increases. Due to their characteristics, these islands are suitable to be used as local artificial substrates for the integration of III–V quantum nanostructures directly on silicon substrate.

  13. Carbon nanotube substrates and catalyzed hot stamp for polishing and patterning the substrates

    Science.gov (United States)

    Wang, Yuhuang; Hauge, Robert H.; Schmidt, Howard K.; Kim, Myung Jong; Kittrell, W. Carter

    2009-09-08

    The present invention is generally directed to catalyzed hot stamp methods for polishing and/or patterning carbon nanotube-containing substrates. In some embodiments, the substrate, as a carbon nanotube fiber end, is brought into contact with a hot stamp (typically at 200-800.degree. C.), and is kept in contact with the hot stamp until the morphology/patterns on the hot stamp have been transferred to the substrate. In some embodiments, the hot stamp is made of material comprising one or more transition metals (Fe, Ni, Co, Pt, Ag, Au, etc.), which can catalyze the etching reaction of carbon with H.sub.2, CO.sub.2, H.sub.2O, and/or O.sub.2. Such methods can (1) polish the carbon nanotube-containing substrate with a microscopically smooth finish, and/or (2) transfer pre-defined patterns from the hot stamp to the substrate. Such polished or patterned carbon nanotube substrates can find application as carbon nanotube electrodes, field emitters, and field emitter arrays for displays and electron sources.

  14. Fungal and bacterial utilization of organic substrates depends on substrate complexity and N availability.

    Science.gov (United States)

    Koranda, Marianne; Kaiser, Christina; Fuchslueger, Lucia; Kitzler, Barbara; Sessitsch, Angela; Zechmeister-Boltenstern, Sophie; Richter, Andreas

    2014-01-01

    There is growing evidence of a direct relationship between microbial community composition and function, which implies that distinct microbial communities vary in their functional properties. The aim of this study was to determine whether differences in initial substrate utilization between distinct microbial communities are due to the activities of certain microbial groups. We performed a short-term experiment with beech forest soils characterized by three different microbial communities (winter and summer community, and a community from a tree-girdling plot). We incubated these soils with different (13) C-labelled substrates with or without inorganic N addition and analyzed microbial substrate utilization by (13) C-phospholipid fatty acid (PLFA) analysis. Our results revealed that the fate of labile C (glucose) was similar in the three microbial communities, despite differences in absolute substrate incorporation between the summer and winter community. The active microbial community involved in degradation of complex C substrates (cellulose, plant cell walls), however, differed between girdling and control plots and was strongly affected by inorganic N addition. Enhanced N availability strongly increased fungal degradation of cellulose and plant cell walls. Our results indicate that fungi, at least in the presence of a high N supply, are the main decomposers of polymeric C substrates.

  15. Evaluation of substrates for butanol production

    Energy Technology Data Exchange (ETDEWEB)

    Compere, A.L.; Griffith, W.L.

    1979-01-01

    The production was evaluated of ethanol, acetone, and butanol from several different carbohydrate materials by five strains of Clostridia and two mixed cultures. The substrates, which were tested at concn ranging between 2.5 and 10% w/v, included pentoses, hexoses, disaccharides, and polysaccharides. The organisms used were Clostridium acetobutylicum strains NRRL B527 and NRRL B3179; Clostridium butylicum strains NRRL B592 and NRRL B593; and Clostridium pasteurianum strain NRRL B598. The mixed cultures contained all of these organisms. Mixed culture 1 contained in addition to the Clostridia, Klebsiella pneumoniae strain NRRL B427. Mixed culture 2 contained mixed culture 1 plus a yeast isolated from kefir culture. Where possible, maxima were found for the conversion of different substrates. 7 tables.

  16. Optical substrate materials for synchrotron radiation beamlines

    Energy Technology Data Exchange (ETDEWEB)

    Howells, M.R. [Lawrence Berkeley National Lab., CA (United States). Advanced Light Source; Paquin, R.A. [Univ. of Arizona, Tucson, AZ (United States). Optical Sciences Center

    1997-06-01

    The authors consider the materials choices available for making optical substrates for synchrotron radiation beam lines. They find that currently the optical surfaces can only be polished to the required finish in fused silica and other glasses, silicon, CVD silicon carbide, electroless nickel and 17-4 PH stainless steel. Substrates must therefore be made of one of these materials or of a metal that can be coated with electroless nickel. In the context of material choices for mirrors they explore the issues of dimensional stability, polishing, bending, cooling, and manufacturing strategy. They conclude that metals are best from an engineering and cost standpoint while the ceramics are best from a polishing standpoint. They then give discussions of specific materials as follows: silicon carbide, silicon, electroless nickel, Glidcop{trademark}, aluminum, precipitation-hardening stainless steel, mild steel, invar and superinvar. Finally they summarize conclusions and propose ideas for further research.

  17. A cellular glass substrate solar concentrator

    Science.gov (United States)

    Bedard, R.; Bell, D.

    1980-01-01

    The design of a second generation point focusing solar concentration is discussed. The design is based on reflective gores fabricated of thin glass mirror bonded continuously to a contoured substrate of cellular glass. The concentrator aperture and structural stiffness was optimized for minimum concentrator cost given the performance requirement of delivering 56 kWth to a 22 cm diameter receiver aperture with a direct normal insolation of 845 watts sq m and an operating wind of 50 kmph. The reflective panel, support structure, drives, foundation and instrumentation and control subsystem designs, optimized for minimum cost, are summarized. The use of cellular glass as a reflective panel substrate material is shown to offer significant weight and cost advantages compared to existing technology materials.

  18. Signal Peptidase Enzymology and Substrate Specificity Profiling.

    Science.gov (United States)

    Dalbey, R E; Pei, D; Ekici, Ö D

    2017-01-01

    Signal peptidases are membrane proteases that play crucial roles in the protein transport pathway of bacteria. They cleave off the signal peptide from precursor proteins that are membrane inserted by the SecYEG or Tat translocons. Signal peptide cleavage releases the translocated protein from the inner membrane allowing the protein to be exported to the periplasm, outer membrane, or secreted into the medium. Signal peptidases are very important proteins to study. They are unique serine proteases with a Ser-Lys dyad, catalyze cleavage at the membrane surface, and are promising potential antibacterial drug targets. This chapter will focus on the isolation of signal peptidases and the preprotein substrates, as well as describe a peptide library approach for characterizing the substrate specificity.

  19. Lithographically patterned silicon nanostructures on silicon substrates

    Energy Technology Data Exchange (ETDEWEB)

    Megouda, Nacera [Institut de Recherche Interdisciplinaire (IRI, USR 3078), Universite Lille1, Parc de la Haute Borne, 50 Avenue de Halley-BP 70478, 59658 Villeneuve d' Ascq and Institut d' Electronique, de Microelectronique et de Nanotechnologie (IEMN, CNRS-8520), Cite Scientifique, Avenue Poincare-B.P. 60069, 59652 Villeneuve d' Ascq (France); Faculte des Sciences, Universite Mouloud Mammeri, Tizi-Ouzou (Algeria); Unite de Developpement de la Technologie du Silicium (UDTS), 2 Bd. Frantz Fanon, B.P. 140 Alger-7 merveilles, Alger (Algeria); Piret, Gaeelle; Galopin, Elisabeth; Coffinier, Yannick [Institut de Recherche Interdisciplinaire (IRI, USR 3078), Universite Lille1, Parc de la Haute Borne, 50 Avenue de Halley-BP 70478, 59658 Villeneuve d' Ascq and Institut d' Electronique, de Microelectronique et de Nanotechnologie (IEMN, CNRS-8520), Cite Scientifique, Avenue Poincare-B.P. 60069, 59652 Villeneuve d' Ascq (France); Hadjersi, Toufik, E-mail: hadjersi@yahoo.com [Unite de Developpement de la Technologie du Silicium (UDTS), 2 Bd. Frantz Fanon, B.P. 140 Alger-7 merveilles, Alger (Algeria); Elkechai, Omar [Faculte des Sciences, Universite Mouloud Mammeri, Tizi-Ouzou (Algeria); and others

    2012-06-01

    The paper reports on controlled formation of silicon nanostructures patterns by the combination of optical lithography and metal-assisted chemical dissolution of crystalline silicon. First, a 20 nm-thick gold film was deposited onto hydrogen-terminated silicon substrate by thermal evaporation. Gold patterns (50 {mu}m Multiplication-Sign 50 {mu}m spaced by 20 {mu}m) were transferred onto the silicon wafer by means of photolithography. The etching process of crystalline silicon in HF/AgNO{sub 3} aqueous solution was studied as a function of the silicon resistivity, etching time and temperature. Controlled formation of silicon nanowire arrays in the unprotected areas was demonstrated for highly resistive silicon substrate, while silicon etching was observed on both gold protected and unprotected areas for moderately doped silicon. The resulting layers were characterized using scanning electron microscopy (SEM).

  20. Substrate Integrated Evanescent Filters Employing Coaxial Stubs

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy

    2015-01-01

    Evanescent mode substrate integrated waveguide (SIW) is one of the promising technologies for design of light-weight low-cost microwave components. Traditional realization methods used in the standard evanescent waveguide technology are often not directly applicable to SIW due to dielectric filling...... and small height of the waveguide. In this work, one of the realization methods of evanescent mode waveguides using a single layer substrate is considered. The method is based on the use of coaxial stubs as capacitive susceptances externally connected to a SIW. A microwave filter based on these principles...... of the microwave filter are discussed. The approach is useful in applications where a sharp roll-off at the upper stop-band is required....

  1. Standard method for characterizing SERS substrates

    Science.gov (United States)

    Guicheteau, Jason A.; Hankus, Mikella E.; Christesen, Steven D.; Fountain, Augustus W., III; Pellegrino, Paul M.; Emmons, Erik D.; Tripathi, Ashish; Wilcox, Phillip; Emge, Darren

    2012-06-01

    We present the methodology and results of a standard assessment protocol to evaluate disparate SERS substrates that were developed for the Defense Advanced Research Programs Agency (DARPA) SERS Science and Technology Fundamentals Program. The results presented are a snapshot of a collaborative effort between the US Army Edgewood Chemical Biological Center, and the US Army Research Laboratory-Aldelphi Laboratory Center to develop a quantitative analytical method with spectroscopic figures of merit to unambiguously compare the sensitivity and reproducibility of various SERS substrates submitted by the program participants. We present the design of a common assessment protocol and the definition of a SERS enhancement value (SEV) in order to effectively compare SERS active surfaces.

  2. Anisotropic artificial substrates for microwave applications

    Science.gov (United States)

    Shahvarpour, Attieh

    ) with very low-beam squint, which makes it particularly appropriate for applications in wide band point-to-point communication and radar systems. The antenna is constituted of a mushroom type anisotropic magneto-dielectric artificial grounded slab with uniaxially anisotropic permittivity and permeability tensors. A spectral transmission-line model based on Green functions approach is chosen for the analysis of the structure. A rigorous comparison between the isotropic and anisotropic leaky-wave antennas is performed which reveals that as opposed to anisotropic slabs, isotropic slabs show weak performance in leaky-wave antennas. The properties of planar antennas such as low profile, low cost, compatibility with integrated circuits and their conformal nature have made them appropriate antennas for communications systems. In parallel, bandwidth and miniaturization requirements have increased the demand for millimeter-wave wireless systems, such as radar, remote sensors and highspeed local area networks. However, as frequency increases towards millimeter-wave regime, the radiation efficiency of planar antennas becomes an important issue. This is due to the increased electrical thickness of the substrate and therefore increased number of the excited surface modes which carry part of the energy of the system in the substrate without any efficient contribution to radiation. Therefore, these antennas suffer from low radiation efficiency. This has motivated the third contribution of the thesis which is the interpretation and analysis of the radiation efficiency behavior of the planar antennas on electrically thick substrates. A novel substrate dipole approach is introduced for the explanation of the efficiency behavior. This dipole models the substrate and reduces the problem of the horizontal electric source on the substrate to an equivalent dipole radiating in the free-space. In addition, in this work, some efficiency enhancement solutions at the electrical thicknesses where

  3. Using Wheat Bran as a Substrate

    Directory of Open Access Journals (Sweden)

    Jessyca dos Reis Celestino

    2014-01-01

    Full Text Available The aim of this study was screening fungi strains, isolated from manipueira (a liquid subproduct obtained from the flour production of Manihot esculenta, for amylases production and investigating production of these enzymes by the strain Aspergillus 6V4. The fungi isolated from manipueira belonged to Ascomycota phylum. The strain Aspergillus 6V4 was the best amylase producer in the screening assay of starch hydrolysis in petri dishes (ASHPD and in the assay in submerged fermentation (ASbF. The strain Aspergillus 6V4 produced high amylase levels (335 UI/L using wheat bran infusion as the exclusive substrate and the supplementation of this substrate with peptone decreased the production of this enzyme. The moisture content of 70% was the best condition for the production of Aspergillus 6V4 amylases (385 IU/g in solid state fermentation (SSF.

  4. Method for producing substrates for superconducting layers

    DEFF Research Database (Denmark)

    2013-01-01

    There is provided a method for producing a substrate (600) suitable for supporting an elongated superconducting element, wherein, e.g., a deformation process is utilized in order to form disruptive strips in a layered solid element, and where etching is used to form undercut volumes (330, 332......) between an upper layer (316) and a lower layer (303) of the layered solid element. Such relatively simple steps enable providing a substrate which may be turned into a superconducting structure, such as a superconducting tape, having reduced AC losses, since the undercut volumes (330, 332) may be useful...... for separating layers of material. In a further embodiment, there is placed a superconducting layer on top of the upper layer (316) and/or lower layer (303), so as to provide a superconducting structure with reduced AC losses....

  5. Development of Mullite Substrates and Containers

    Science.gov (United States)

    Sibold, J. D.

    1979-01-01

    The mullite-molten silicon interaction was evaluated through fabrication of a series of bodies made with variations in density, alumina-silica ratio, and glass-crystalline ratio. The materials were tested in a sessile drop technique. None of the variations stood up to extended exposure to molten silicon sufficiently to be recommended as a container material. However, directional solidification experiments suggest that, under proper conditions, contamination of the silicon by mullite containers can be minimized. To improve an already good thermal expansion match between mullite and silicon, compositional variations were studied. Altering of the alumina-silica ratio was determined to give a continuously varying thermal expansion. A standard mullite composition was selected and substrates 40 x 4 x .040 inches were fabricated. Slotted substrates of various configurations and various compositions were also fabricated.

  6. Enhanced photoacoustic detection using photonic crystal substrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yunfei; Liu, Kaiyang [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); McClelland, John [Ames Laboratory-USDOE, Ames, Iowa 50011 (United States); Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011 (United States); Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011 (United States); Lu, Meng, E-mail: menglu@iastate.edu [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011 (United States)

    2014-04-21

    This paper demonstrates the enhanced photoacoustic sensing of surface-bound light absorbing molecules and metal nanoparticles using a one-dimensional photonic crystal (PC) substrate. The PC structure functions as an optical resonator at the wavelength where the analyte absorption is strong. The optical resonance of the PC sensor provides an intensified evanescent field with respect to the excitation light source and results in enhanced optical absorption by surface-immobilized samples. For the analysis of a light absorbing dye deposited on the PC surface, the intensity of photoacoustic signal was enhanced by more than 10-fold in comparison to an un-patterned acrylic substrate. The technique was also applied to detect gold nanorods and exhibited more than 40 times stronger photoacoustic signals. The demonstrated approach represents a potential path towards single molecule absorption spectroscopy with greater performance and inexpensive instrumentation.

  7. Microorganisms detection on substrates using QCL spectroscopy

    Science.gov (United States)

    Padilla-Jiménez, Amira C.; Ortiz-Rivera, William; Castro-Suarez, John R.; Ríos-Velázquez, Carlos; Vázquez-Ayala, Iris; Hernández-Rivera, Samuel P.

    2013-05-01

    Recent investigations have focused on the improvement of rapid and accurate methods to develop spectroscopic markers of compounds constituting microorganisms that are considered biological threats. Quantum cascade lasers (QCL) systems have revolutionized many areas of research and development in defense and security applications, including his area of research. Infrared spectroscopy detection based on QCL was employed to acquire mid infrared (MIR) spectral signatures of Bacillus thuringiensis (Bt), Escherichia coli (Ec) and Staphylococcus epidermidis (Se), which were used as biological agent simulants of biothreats. The experiments were carried out in reflection mode on various substrates such as cardboard, glass, travel baggage, wood and stainless steel. Chemometrics statistical routines such as principal component analysis (PCA) regression and partial least squares-discriminant analysis (PLS-DA) were applied to the recorded MIR spectra. The results show that the infrared vibrational techniques investigated are useful for classification/detection of the target microorganisms on the types of substrates studied.

  8. Hydrogenation of biomass-derived substrates

    Science.gov (United States)

    Gordon, John C.; Waidmann, Christopher R.

    2016-06-07

    The .alpha.,.beta.-unsaturated ketone moiety of a substrate representative of non-food based biomass was hydrogenated to the corresponding saturated alcohol moiety using a composition including (1) a copper salt; (2) a phosphine; (3) a polar aprotic solvent such as acetonitrile, and (4) a compound suitable for providing hydrogen for the hydrogenation, such as a suitable silane material or a suitable siloxane material.

  9. Purity of targets prepared on Cu substrates

    Science.gov (United States)

    Méens, A.; Rossini, I.; Sens, J. C.

    1993-09-01

    The purity of several elemental self-supporting targets usually prepared by evaporation onto soluble Cu substrates has been studied. The targets were analysed by Rutherford backscattering and instrumental neutron activation analysis. Because of the high percentage of Cu observed in some Si targets, further measurements, including transmission electron microscopy, have been performed on Si targets deposited by e-gun bombardment onto Cu and ion-beam sputtering onto betaine.

  10. Reflections on substrate water and dioxygen formation

    OpenAIRE

    Cox, Nicholas; Messinger, Johannes

    2013-01-01

    This brief article aims at presenting a concise summary of all experimental findings regarding substrate water-binding to the Mn4CaO5 cluster in photosystem II. Mass spectrometric and spectroscopic results are interpreted in light of recent structural information of the water oxidizing complex (WOC) obtained by x-ray crystallography, spectroscopy and theoretical modeling. Within this framework current proposals for the mechanism of photosynthetic water-oxidation are evaluated. Special Iss...

  11. Electrodeposition on Superalloy Substrates: a Review

    Science.gov (United States)

    Allahyarzadeh, M. H.; Aliofkhazraei, M.; Rouhaghdam, A. Sabour

    2016-02-01

    The present paper reviews various types of coatings, including platinum, platinum alloys, palladium, ruthenium, iridium, nickel, nickel alloys and composite coatings, on superalloy substrates using electrodeposition method. Attempts were carried out to represent an overall view of plating conditions and electrolyte and highlight the importance of the layer regarding to the performance of high-temperature coatings applied on superalloys, which is extensively used on gas-turbine components.

  12. Advanced organics for electronic substrates and packages

    CERN Document Server

    Fletcher, Andrew E

    1992-01-01

    Advanced Organics for Electronic Substrates and Packages provides information on packaging, which is one of the most technologically intensive activities in the electronics industry. The electronics packaging community has realized that while semiconductor devices continue to be improved upon for performance, cost, and reliability, it is the interconnection or packaging of these devices that will limit the performance of the systems. Technology must develop packaging for transistor chips, with high levels of performance and integration providing cooling, power, and interconnection, and yet pre

  13. Preparation of the Superconductor Substrate: Strontium Titanate

    Science.gov (United States)

    1988-09-01

    single crystals of strontium titanate is derived from the original method developed by Verneuil . 16 The general procedure for the growth of single... crystals growth are reported. The growth direction was determined to be 5 degrees away from the [2111 direction. ICP-emission spectroscopy irdicates... Growth of Strontium Titanate Crystals 5 2.4 Preparation of Substrates 8 3. RESULTS AND CONCLUSIONS 8 REFERENCES 13 Illustrations 1. Schematic Diagram

  14. Substrate-induced strain in carbon nanodisks

    Energy Technology Data Exchange (ETDEWEB)

    Osváth, Z., E-mail: osvath.zoltan@ttk.mta.hu [Institute of Technical Physics and Materials Science, MFA, Research Centre for Natural Sciences, 1525 Budapest, P.O. Box 49 (Hungary); Korea–Hungary Joint Laboratory for Nanosciences (KHJLN), P.O. Box 49, 1525 Budapest (Hungary); Vértesy, Z. [Institute of Technical Physics and Materials Science, MFA, Research Centre for Natural Sciences, 1525 Budapest, P.O. Box 49 (Hungary); Korea–Hungary Joint Laboratory for Nanosciences (KHJLN), P.O. Box 49, 1525 Budapest (Hungary); Lábár, J. [Institute of Technical Physics and Materials Science, MFA, Research Centre for Natural Sciences, 1525 Budapest, P.O. Box 49 (Hungary); Nemes-Incze, P.; Horváth, Z.E.; Biró, L.P. [Institute of Technical Physics and Materials Science, MFA, Research Centre for Natural Sciences, 1525 Budapest, P.O. Box 49 (Hungary); Korea–Hungary Joint Laboratory for Nanosciences (KHJLN), P.O. Box 49, 1525 Budapest (Hungary)

    2014-08-28

    Graphitic nanodisks of typically 20–50 nm in thickness, produced by the so-called Kvaerner Carbon Black and Hydrogen Process were dispersed on gold substrate and investigated by atomic force microscopy (AFM), field emission scanning electron microscopy (FE-SEM), and confocal Raman spectroscopy. The roughness of the gold surface was drastically changed by annealing at 400 °C. AFM measurements show that this change in the surface roughness induces changes also in the topography of the nanodisks, as they closely follow the corrugation of the gold substrate. This leads to strained nanodisks, which is confirmed also by confocal Raman microscopy. We found that the FE-SEM contrast obtained from the disks depends on the working distance used during the image acquisition by In-lens detection, a phenomenon which we explain by the decrease in the amount of electrons reaching the detector due to diffraction. This process may affect the image contrast in the case of other layered materials, like hexagonal boron nitride, and other planar hybrid nanostructures, too. - Highlights: • Bending of carbon nanodisks is induced by the roughness of the gold substrate. • Confocal Raman microscopy shows a compressive strain induced in the nanodisks. • The electron microscopy contrast of nanodisks depends on the working distance.

  15. Effect of streambed substrate on macroinvertebrate biodiversity

    Institute of Scientific and Technical Information of China (English)

    Xuehua DUAN; Zhaoyin WANG; Shimin TIAN

    2008-01-01

    Macroinvertebrates are important components of stream ecosystems, and are often used as indicator spe-cies for the assessment of river ecology. Numerous studies have shown that substrate is the primary physical envir-onmental variable affecting the taxa richness and density of macroinvertebrates. The aim of this work is to study the effects of the characteristics of streambed substrate, such as grain size, shape, and roughness, on the composition and biodiversity of macroinvertebrates. A field experi-ment was done on the Juma River, a second-order moun-tain stream in northern China. Substrata of cobbles, hewn stones, pebbles, coarse sand, and fine sand were used to replace the original gravel and sand bed in a stretch of 30 m in length. The sampling results indicated that the macroinvertebrate assemblage is significantly affected by the grain size, porosity and interstitial dimension of the substrate, while it is rarely affected by the shape and the surface roughness of the experimental substrata. Macroinvertebrate compositions in cobbles and hewn stones were stable and changed least over time. The taxa richness and density of individuals in the substrata of cobbles, hewn stones, and pebbles are much higher than in those of the coarse sand and fine sand.

  16. Method of surface treatment on sapphire substrate

    Institute of Scientific and Technical Information of China (English)

    NIU Xin-huan; LIU Yu-ling; TAN Bai-mei; HAN Li-ying; ZHANG Jian-xin

    2006-01-01

    Sapphire single crystals are widely used in many areas because of the special physic properties and important application value. As an important substrate material,stringent surface quality requirements,i.e. surface finish and flatness,are required. The use of CMP technique can produce high quality surface finishes at low cost and with fast material removal rates. The sapphire substrate surface is treated by using CMP method. According to sapphire substrate and its product properties,SiO2 sol is chosen as abrasive. The particle size is 15-25 nm and the concentration is 40%. According to the experiment results,pH value is 10.5-11.5. After polishing and cleaning the sapphire surface,the surface roughness was measured by using AFM method and the lowest value of Ra 0.1 nm was obtained. From the results,it can be seen that using such method,the optimal sapphire surface can be gotten,which is advantageous for epitaxial growth and device making-up.

  17. Cell-Substrate Adhesion by Amoeboid Cells

    Science.gov (United States)

    Flanders, Bret; Panta, Krishna

    Amoeboid migration is a rapid (10 μm min-1) mode of migration that some tumor cells exhibit. To permit such rapid movement, the adhesive contacts between the cell and the substrate must be relatively short-lived and weak. In this study, we investigate the basic adhesive character of amoeboid cells (D. discoideum) in contact with silanized glass substrates. We observe the initiation and spreading of the adhesive contacts that these cells establish as they settle under gravity onto the substrate and relax towards mechanical equilibrium. The use of interference reflection microscopy and cellular tethering measurements have allowed us to determine the basic adhesive properties of the cell: the membrane-medium interfacial energy; the bending modulus; the equilibrium contact angle; and the work of adhesion. We find the time scale on which settling occurs to be longer than expected. Implications of these results on adhesion and migration will be discussed. The authors are grateful for support from NSF (CBET-1451903) and NIH (1R21EY026392).

  18. Improvement of mechanical properties of glass substrates

    Science.gov (United States)

    Karbay, Ismail Hakki Cengizhan; Budakoglu, Refika; Zayim, Esra Ozkan

    2015-12-01

    This paper aims to enhance the mechanical and optical properties of glass substrates with thin films by the sol-gel method. TiO2-SiO2 binary system and Ta2O5 were deposited on glass substrates with high transparency. Ring-on-ring flexure and scratch tests were the main mechanical characterization tests. Herein, we report that the thin films can be used to enhance the mechanical properties of the glass substrates efficiently and effectively. TiO2-SiO2 binary system shows more than two times and Ta2O5 thin films show nearly three times better ultimate strength in the ring-on-ring flexure test. Besides, Ta2O5 thin film samples show superior scratch resistance. Additionally, the finite element method was also used to check the conformity in the application of mechanical properties of composite materials. It is also worth noting that, the finite element method can be used to accurately analyze the mechanical stability of composite materials. The use of the finite element method can reduce the total number of experimental trials without losing reliability.

  19. Spectral Markers of Erythrocytes on Solid Substrate

    Science.gov (United States)

    Paiziev, Adkhamjon A.; Krakhmalev, V. A.

    Proposed in previous paper [1,2] the new nondestructive method of optical microscopy allows to examine the structures of living cells (human erythrocytes) in their natural colors without its staining by using a specially designed substrate for deposition of biological sample and observing a native blood smears in reflected light. Color interference contrast image is achieved due to special condition of experiment is connected with chose of angle of incidental light, wave length of light of reflected ray, chemical composition of sample, thickness of sample, refractive index of sample, refractive index of substrate, chemical composition of substrate [1,2]. We can identify chemical compounds of erythrocytes after calibration color scale by alternative methods. For comparison we used Synchrotron Radiation based Fourier Transformed Infrared (SR-FTIR) microspectroscopy. By focusing of infrared beam of FTIR microscope on cell surface we can screen and distinguish difference erythrocytes by its color. For example on Fig. 49.1 we can see two neighbored erythrocytes where one of them have red color (point 1) and other-green (point 5). To identify their spectral markers we measured IR absorption spectra of cells at different points (1,2,3,4 and 5). Intermediated area (points 3 and 4) correspond to substrate spectra (silicon substrate) and their spectra are same. The peaks at 2,850 and 2,920 cm-1 correspond mainly to the CH2 stretching modes of the methylene chains in membrane lipids. At 1,650 cm-1 the amide I band is observed, which results, principally, from the n(CO) stretching vibrations of the protein amide bonds; the amide II band, near 1,550 cm-1, is a combination of the d(N-H) bending and n(C-N) stretching vibrations of the amide bonds. The peaks at 2,850 and 2,920 cm-1 correspond mainly to the CH2 stretching modes of the methylene chains in membrane lipids [3. The intensities of the absorption bands at 2,920 and 2,850 cm-1 in green erythrocyte (point 5) were also

  20. Modeling substrate-bacteria-grazer interactions coupled to substrate transport in groundwater

    Science.gov (United States)

    Bajracharya, Bijendra M.; Lu, Chuanhe; Cirpka, Olaf A.

    2014-05-01

    Models of microbial dynamics coupled to solute transport in aquifers typically require the introduction of a bacterial capacity term to prevent excessive microbial growth close to substrate-injection boundaries. The factors controlling this carrying capacity, however, are not fully understood. In this study, we propose that grazers or bacteriophages may control the density of bacterial biomass in continuously fed porous media. We conceptualize the flow-through porous medium as a series of retentostats, in which the dissolved substrate is advected with water flow whereas the biomasses of bacteria and grazers are considered essentially immobile. We first model a single retentostat with Monod kinetics of bacterial growth and a second-order grazing law, which shows that the system oscillates but approaches a stable steady state with nonzero concentrations of substrate, bacteria, and grazers. The steady state concentration of the bacteria biomass is independent of the substrate concentration in the inflow. When coupling several retentostats in a series to mimic a groundwater column, the steady state bacteria concentrations thus remain at a constant level over a significant travel distance. The one-dimensional reactive transport model also accounts for substrate dispersion and a random walk of grazers influenced by the bacteria concentration. These dispersive-diffusive terms affect the oscillations until steady state is reached, but hardly the steady state value itself. We conclude that grazing, or infection by bacteriophages, is a possible explanation of the maximum biomass concentration frequently needed in bioreactive transport models. Its value depends on parameters related to the grazers or bacteriophages and is independent of bacterial growth parameters or substrate concentration, provided that there is enough substrate to sustain bacteria and grazers.

  1. Effect of substrate roughness on the contact damage of thin brittle films on brittle substrates

    Energy Technology Data Exchange (ETDEWEB)

    Weidner, Mirko [School of Materials Science and Engineering, University of New South Wales NSW 2052, Sydney (Australia); Institute for Materials Science, Technische Universitaet Darmstadt, Petersenstrasse 23, 64287 Darmstadt (Germany); Borrero-Lopez, Oscar [School of Materials Science and Engineering, University of New South Wales NSW 2052, Sydney (Australia); Departamento de Ingenieria Mecanica, Energetica y de los Materiales, Universidad de Extremadura, 06071, Badajoz (Spain); Hoffman, Mark, E-mail: mark.hoffman@unsw.edu.a [School of Materials Science and Engineering, University of New South Wales NSW 2052, Sydney (Australia); Bendavid, Avi; Martin, Phil J. [CSIRO Materials Science and Engineering, P.O. Box 218, Lindfield NSW 2070 (Australia)

    2010-07-01

    The effect of substrate and surface roughness on the contact fracture of diamond-like carbon coatings on brittle soda-lime glass substrates has been investigated. The average surface roughness (R{sub a}) of the examined samples ranged from 15 nm to 571 nm. Contact damage was simulated by means of spherical nanoindentation, and fracture was subsequently assessed by focused ion beam microscopy. It was found that, in the absence of sub-surface damage in the substrate, fracture occurs in the coating in the form of radial, and ring/cone cracks during loading, and lateral cracks during unloading. Increasing the surface roughness results in a decrease in the critical load for crack initiation during loading, and in the suppression of fracture modes during unloading from high loads. When sub-surface damage (lateral cracks) is present in the substrate, severe spalling takes place during loading, causing a large discontinuity in the load-displacement curve. The results have implications concerning the design of damage-tolerant coated systems consisting of a brittle film on a brittle substrate.

  2. Enzyme analysis for Pompe disease in leukocytes; superior results with natural substrate compared with artificial substrates.

    Science.gov (United States)

    van Diggelen, O P; Oemardien, L F; van der Beek, N A M E; Kroos, M A; Wind, H K; Voznyi, Y V; Burke, D; Jackson, M; Winchester, B G; Reuser, A J J

    2009-06-01

    Enzyme analysis for Pompe disease in leukocytes has been greatly improved by the introduction of acarbose, a powerful inhibitor of interfering alpha-glucosidases, which are present in granulocytes but not in lymphocytes. Here we show that the application of acarbose in the enzymatic assay employing the artificial substrate 4-methylumbelliferyl-alpha-D: -glucoside (MU-alphaGlc) is insufficient to clearly distinguish patients from healthy individuals in all cases. Also, the ratios of the activities without/with acarbose only marginally discriminated Pompe patients and healthy individuals. By contrast, when the natural substrate glycogen is used, the activity in leukocytes from patients (n = 82) with Pompe disease is at most 17% of the lowest control value. The use of artificial substrate in an assay with isolated lymphocytes instead of total leukocytes is a poor alternative as blood samples older than one day invariably yield lymphocyte preparations that are contaminated with granulocytes. To diagnose Pompe disease in leukocytes we recommend the use of glycogen as substrate in the presence of acarbose. This assay unequivocally excludes Pompe disease. To also exclude pseudo-deficiency of acid alpha-glucosidase caused by the sequence change c.271G>A (p.D91N or GAA2; homozygosity in approximately 1:1000 caucasians), a second assay employing MU-alphaGlc substrate plus acarbose or DNA analysis is required.

  3. Association of endogenous substrate with solubilized bovine brain sialidase.

    Science.gov (United States)

    Schengrund, C L; Repman, M A

    1986-01-01

    Nonidet P40 solubilized up to 90% of the sialidase, active towards added ganglioside substrate, that was associated with the total membrane fraction prepared from gray matter of bovine brains. Solubilized sialidase acted upon endogenous substrate (sialic acid containing compounds solubilized with the enzyme), hydrolyzing approximately 50% of the readily available sialosyl residues within 20 min. During a 2-hr reaction time 80% of the polysialylated gangliosides solubilized with the enzyme were acted upon. A 20-min lag was observed before sialidase acted upon added ganglioside substrate. The lag could be reduced to less than 2 min when the enzyme was allowed to act on endogenous substrate prior to exposure to exogenous substrate, suggesting that the solubilized enzyme acted preferentially on endogenous substrate. A protease inhibitor prevented much of the 86% loss of activity towards added substrate that was seen when the enzyme was stored at 4 degrees C for 6 days; activity towards endogenous substrate decreased only 34%.

  4. A sparse scattering model for nanoparticles on rough substrates

    DEFF Research Database (Denmark)

    Karamehmedovic, Mirza; Hansen, Poul-Erik; Wriedt, Thomas

    2013-01-01

    We present and validate an efficient forward scattering model for nanoparticles on rough contaminated substrates.......We present and validate an efficient forward scattering model for nanoparticles on rough contaminated substrates....

  5. Nemesia Root Hair Response to Paper Pulp Substrate for Micropropagation

    OpenAIRE

    Pascal Labrousse; David Delmail; Raphaël Decou; Michel Carlué; Sabine Lhernould; Pierre Krausz,

    2012-01-01

    Agar substrates for in vitro culture are well adapted to plant micropropagation, but not to plant rooting and acclimatization. Conversely, paper-pulp-based substrates appear as potentially well adapted for in vitro culture and functional root production. To reinforce this hypothesis, this study compares in vitro development of nemesia on several substrates. Strong differences between nemesia roots growing in agar or in paper-pulp substrates were evidenced through scanning electron microscopy....

  6. Nanostructured surface enhanced Raman scattering substrates for explosives detection

    DEFF Research Database (Denmark)

    Schmidt, Michael Stenbaek; Olsen, Jesper Kenneth; Boisen, Anja;

    2010-01-01

    Here we present a method for trace detection of explosives in the gas phase using novel surface enhanced Raman scattering (SERS) spectroscopy substrates. Novel substrates that produce an exceptionally large enhancement of the Raman effect were used to amplify the Raman signal of explosives molecu...... process compared to existing commercial substrates. Therefore it is believed that these novel substrates will be able to make SERS more applicable in mobile explosives detection systems to be deployed in for example landmine clearance actions....

  7. Rich variety of substrates for surface enhanced Raman spectroscopy

    Science.gov (United States)

    Nguyen, Bich Ha; Hieu Nguyen, Van; Nhung Tran, Hong

    2016-09-01

    The efficiency of the application of surface enhanced Raman spectroscopy (SERS) technique to each specified purpose significantly depends on the choice of the SERS substrate with an appropriate structure as well as on its performance. Until the present time a rich variety of SERS substrates was fabricated. They can be classified according to their structures. The present work is a review of main types of SERS substrates for using in the trace analysis application. They can be classified into 4 groups: (1) Substrates using gold nanoparticles (AuNPs) with spherical shape such as colloidal AuNPs, AuNPs fabricated by pulsed laser deposition, by sputtering or by capillary force assembly (CFA), substrates fabricated by electrospinning technique, substrates using metallic nanoparticle arrays fabricated by electron beam lithography combined with CFA method, substrates using silver nanoparticle (AgNP) arrays grain by chemical seeded method, substrates with tunable surface plasmon resonance, substrates based on precies subnanometer plasmonic junctions within AuNP assemblies, substrates fabricated by simultaneously immobilizing both AuNPs and AgNPs on the same glass sides etc. (2) Substrates using nanostructures with non-spherical shapes such as gold nanowire (NW), or highly anisotropic nickel NW together with large area, free-standing carpets, substrates with obviously angular, quasi-vertically aligned cuboid-shaped TiO2 NW arrays decorated with AgNPs, substrates using gold nanoprism monolayer films, substrates using silver nanocube dimmers or monodisperse close-packed gold nanotriangle monolayers. (3) Substrates using multiparticle complex nanostructure such as nanoparticle cluster arrays, gold nanoflowers and nanodendrites. (4) Flexible substrate such as paper-based swab with gold nanorods, adhesive polymer tapes fabricated by inkjet printing method and flexible and adhesive SERS tapes fabricated by decorating AuNPs via the conventional drop-dry method.

  8. Substrate influences ecophysiological performance of tree seedlings.

    Science.gov (United States)

    Pröll, Gisela; Hietz, Peter; Delaney, Christina M; Katzensteiner, Klaus

    2016-01-01

    Unfavourable soil conditions frequently limit tree regeneration in mountain forests on calcareous bedrock. Rocky, shallow organic soils on dolomite pose a particular problem for tree regeneration due to commonly restricted water and nutrient supplies. Moreover, an often dense layer of understorey vegetation competes for the limited resources available. Hence, an array of interacting factors impairs tree seedlings' performance on dolomite, but there is little information on the ecophysiological mechanisms. We studied the effects of substrate, competing vegetation and foliar nutrient concentrations on the photosynthetic rate (A), stomatal conductance (gs) and leaf water potentials (ψ) of sycamore (Acer pseudoplatanus L.), beech (Fagus sylvatica L.), spruce [Picea abies (L.) Karst.] and larch (Larix decidua Mill.) under controlled (well-watered/drought-stressed) conditions and under prevailing field conditions. While A and gs of well-watered spruce in the pot experiment were reduced by the mineral substrate, the organic dolomite substrate with dense competing vegetation reduced gs and ψ of sycamore, spruce and larch under drought-stressed conditions in the field. For sycamore and spruce, A and gs were strongly correlated with foliar nitrogen (N) and potassium (K) concentrations in the pot experiment. In contrast, soil water primarily affected beech and larch. Finally, dense competing vegetation negatively affected A and gs of spruce and A of larch on dolomite. Our results highlight the critical role of N, K and water availability for tree seedlings in shallow soils on calcareous bedrock. On these sites, natural tree regeneration is at particular risk from episodic drought, a likely consequence of climate change.

  9. Thin film reactions on alloy semiconductor substrates

    Energy Technology Data Exchange (ETDEWEB)

    Olson, D.A.

    1990-11-01

    The interactions between Pt and In{sub .53}Ga{sub .47}As have been studied. In{sub .53}Ga{sub .47}As substrates with 70nm Pt films were encapsulated in SiO{sub 2}, and annealed up to 600{degree}C in flowing forming gas. The composition and morphology of the reaction product phases were studied using x-ray diffraction, Auger depth profiling, and transmission electron microscopy. The reaction kinetics were examined with Rutherford Backscattering. Results show that Pt/In{sub .53}Ga{sub .47}As reacts to form many of the reaction products encountered in the Pt/GaAs and Pt/InP reactions: PtGa, Pt{sub 3}Ga, and PtAs{sub 2}. In addition, a ternary phase, Pt(In:Ga){sub 2}, develops, which is a solid solution between PtIn{sub 2} and PtGa{sub 2}. The amount of Ga in the ternary phase increases with annealing temperature, which causes a decrease in the lattice parameter of the phase. The reaction products show a tendency to form layered structures, especially for higher temperatures and longer annealing times. Unlike the binary case, the PtAs{sub 2}, phase is randomly oriented on the substrate, and is intermingle with a significant amount of Pt(In:Ga){sub 2}. Following Pt/In{sub .53}Ga{sub .47}As reactions, two orientation relationships between the Pt(In:Ga){sub 2} product phase and the substrate were observed, despite the large mismatch with the substrate ({approximately}8%). For many metal/compound semiconductor interactions, the reaction rate is diffusion limited, i.e. exhibits a parabolic dependence on time. An additional result of this study was the development of an In-rich layer beneath the reacted layer. The Auger depth profile showed a substantial increase in the sample at this layer. This is a significant result for the production of ohmic contacts, as the Schottky barrier height in this system lower for higher In concentrations. 216 refs.

  10. Improved Barrier Properties in Flexible Plastic Substrates

    Science.gov (United States)

    2009-01-01

    adhesion. We also tried double-sided adhesive tape ( thickness 10jim), UV curable adhesive and heat- curable adhesive65 to form a bond between mica and...Figure 3.9. Picture of stack (2.5"x2.5") made with UV curable adhesive- two PEN substrates (125nm thick ) sandwich 4 mica films (5^m thick each...double layer coating by simultaneously evaporating Al203 and Si02 by one e-beam-gun. 22 For a thickness of 50nm, the oxygen transmission rate achieved

  11. Macro algae as substrate for biogas production

    DEFF Research Database (Denmark)

    Møller, Henrik; Sarker, Shiplu; Gautam, Dhan Prasad

    Algae as a substrate for biogas is superior to other crops since it has a much higher yield of biomass per unit area and since algae grows in the seawater there will be no competition with food production on agricultural lands. So far, the progress in treating different groups of algae as a source...... of energy is promising. In this study 5 different algae types were tested for biogas potential and two algae were subsequent used for co-digestion with manure. Green seaweed, Ulva lactuca and brown seaweed Laminaria digitata was co-digested with cattle manure at mesophilic and thermophilic condition...

  12. Metallic substrates for high temperature superconductors

    Science.gov (United States)

    Truchan, Thomas G.; Miller, Dean J.; Goretta, Kenneth C.; Balachandran, Uthamalingam; Foley, Robert

    2002-01-01

    A biaxially textured face-centered cubic metal article having grain boundaries with misorientation angles greater than about 8.degree. limited to less than about 1%. A laminate article is also disclosed having a metal substrate first rolled to at least about 95% thickness reduction followed by a first annealing at a temperature less than about 375.degree. C. Then a second rolling operation of not greater than about 6% thickness reduction is provided, followed by a second annealing at a temperature greater than about 400.degree. C. A method of forming the metal and laminate articles is also disclosed.

  13. Methods for both coating a substrate with aluminum oxide and infusing the substrate with elemental aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jung-Pyung; Weil, Kenneth Scott

    2016-11-01

    Methods of aluminizing the surface of a metal substrate. The methods of the present invention do not require establishment of a vacuum or a reducing atmosphere, as is typically necessary. Accordingly, aluminization can occur in the presence of oxygen, which greatly simplifies and reduces processing costs by allowing deposition of the aluminum coating to be performed, for example, in air. Embodiments of the present invention can be characterized by applying a slurry that includes a binder and powder granules containing aluminum to the metal substrate surface. Then, in a combined step, a portion of the aluminum is diffused into the substrate and a portion of the aluminum is oxidized by heating the slurry to a temperature greater than the melting point of the aluminum in an oxygen-containing atmosphere.

  14. Single-crystal semiconductor films grown on foreign substrates

    Science.gov (United States)

    Vohl, P.

    1966-01-01

    Intermediate alloy formed between foreign substrates and semiconductor material enable the growth of single crystal semiconductor films on the alloy layer. The melted film must not ball up on the surface of the substrate and neither chemically react nor alloy with the intermediate alloy formed on the substrate.

  15. Substrate-induced bulk alignment of liquid crystals

    DEFF Research Database (Denmark)

    Zhang, Zhengping; Chakrabarti, A.; Mouritsen, Ole G.;

    1996-01-01

    The Gay-Berne model for liquid crystals in the presence of a substrate surface is studied using the hybrid Monte Carlo method. A simple non-mean-field substrate-molecule potential is proposed to describe the effects of rubbed polymer-coated substrates on the liquid crystals. Effects...

  16. Preparation of Porosity-Graded SOFC Anode Substrates

    NARCIS (Netherlands)

    Holtappels, P.; Sorof, C.; Verbraeken, M.C.; Rambert, S.; Vogt, U.

    2006-01-01

    Porosity graded anode substrates for solid oxide fuel cells are considered to optimise the gas transport through the substrate by maintaining a high electrochemical activity for fuel oxidation at the anode/solid electrolyte interface. In this work, the fabrication of porosity graded anode substrates

  17. Stress of electroless copper deposits on insulating and metal substrates

    Energy Technology Data Exchange (ETDEWEB)

    Brüning, Ralf, E-mail: rbruening@mta.ca [Physics Department, Mount Allison University, Sackville, New Brunswick E4L 1E6 (Canada); Sibley, Allison; Sharma, Tanu; Brown, Delilah A.; Demay, Thibault [Physics Department, Mount Allison University, Sackville, New Brunswick E4L 1E6 (Canada); Brüning, Frank; Bernhard, Tobias [Atotech Deutschland GmbH, Erasmusstrasse 20, 10553 Berlin (Germany)

    2014-08-28

    In the fabrication of printed circuit boards, electroless copper is plated on insulating substrates. However, data for film stress by substrate bending are frequently obtained with metal substrates. We compare the stress evolution on an insulating substrate (acrylonitrile butadiene styrene) with results from commercial Ni–Fe and Cu–Fe alloy test strips, as well as X-ray diffraction based strain data. Tests were done with two plating bath formulations, one with and one without added nickel. Substrate type and condition determine the stress near the beginning of plating. Stress of the Ni-free films depends more strongly on the substrate material. Further, when the samples are cooled from the bath operating temperature to room temperature, the thermal contraction of the insulating substrate compresses the plated thin copper film. The measured stress change agrees with the change predicted by calculation. Data correction methods are discussed, and other substrate materials can be tested readily with the method employed here. - Highlights: • We report stress of electroless Cu deposits on insulating and metal substrates. • The final deposit stress is substrate-independent. • The final deposit stress and the X-ray diffraction based strain agree. • The stress change due to the thermal contraction of the substrate is observed. • Plating bath type, substrate and surface preparation alter the stress.

  18. Graphene-on-semiconductor substrates for analog electronics

    Science.gov (United States)

    Lagally, Max G.; Cavallo, Francesca; Rojas-Delgado, Richard

    2016-04-26

    Electrically conductive material structures, analog electronic devices incorporating the structures and methods for making the structures are provided. The structures include a layer of graphene on a semiconductor substrate. The graphene layer and the substrate are separated by an interfacial region that promotes transfer of charge carriers from the surface of the substrate to the graphene.

  19. Method of forming through substrate vias (TSVs) and singulating and releasing die having the TSVs from a mechanical support substrate

    Science.gov (United States)

    Okandan, Murat; Nielson, Gregory N

    2014-12-09

    Accessing a workpiece object in semiconductor processing is disclosed. The workpiece object includes a mechanical support substrate, a release layer over the mechanical support substrate, and an integrated circuit substrate coupled over the release layer. The integrated circuit substrate includes a device layer having semiconductor devices. The method also includes etching through-substrate via (TSV) openings through the integrated circuit substrate that have buried ends at or within the release layer including using the release layer as an etch stop. TSVs are formed by introducing one or more conductive materials into the TSV openings. A die singulation trench is etched at least substantially through the integrated circuit substrate around a perimeter of an integrated circuit die. The integrated circuit die is at least substantially released from the mechanical support substrate.

  20. An Efficient and Accurate Method of Estimating Substrate Noise Coupling in Heavily Doped Substrates

    Science.gov (United States)

    2005-08-24

    αij values obtained from the original contact sizes. The αij calculated using the model is the same for both the cases. The error from this model is...substrate resistances in large circuits,” in Proc. European Design and Test Conference, March 1996, pp. 560-565. [5] E. Charbon , R. Gharpurey, P. Miliozzi...and E. Charbon , “Substrate coupling: modeling, simulation and design perspectives,” in Proc. of Quality Electronic Design, March 2004, pp. 283-290. [8

  1. The neural substrate of gesture recognition.

    Science.gov (United States)

    Villarreal, Mirta; Fridman, Esteban A; Amengual, Alejandra; Falasco, German; Gerschcovich, Eliana Roldan; Gerscovich, Eliana Roldan; Ulloa, Erlinda R; Leiguarda, Ramon C

    2008-01-01

    Previous studies have linked action recognition with a particular pool of neurons located in the ventral premotor cortex, the posterior parietal cortex and the superior temporal sulcus (the mirror neuron system). However, it is still unclear if transitive and intransitive gestures share the same neural substrates during action-recognition processes. In the present study, we used event-related functional magnetic resonance imaging (fMRI) to assess the cortical areas active during recognition of pantomimed transitive actions, intransitive gestures, and meaningless control actions. Perception of all types of gestures engaged the right pre-supplementary motor area (pre-SMA), and bilaterally in the posterior superior temporal cortex, the posterior parietal cortex, occipitotemporal regions and visual cortices. Activation of the posterior superior temporal sulcus/superior temporal gyrus region was found in both hemispheres during recognition of transitive and intransitive gestures, and in the right hemisphere during the control condition; the middle temporal gyrus showed activation in the left hemisphere when subjects recognized transitive and intransitive gestures; activation of the left inferior parietal lobe and intraparietal sulcus (IPS) was mainly observed in the left hemisphere during recognition of the three conditions. The most striking finding was the greater activation of the left inferior frontal gyrus (IFG) during recognition of intransitive actions. Results show that a similar neural substrate, albeit, with a distinct engagement underlies the cognitive processing of transitive and intransitive gestures recognition. These findings suggest that selective disruptions in these circuits may lead to distinct clinical deficits.

  2. Neural substrates of sublexical processing for spelling.

    Science.gov (United States)

    DeMarco, Andrew T; Wilson, Stephen M; Rising, Kindle; Rapcsak, Steven Z; Beeson, Pélagie M

    2017-01-01

    We used fMRI to examine the neural substrates of sublexical phoneme-grapheme conversion during spelling in a group of healthy young adults. Participants performed a writing-to-dictation task involving irregular words (e.g., choir), plausible nonwords (e.g., kroid), and a control task of drawing familiar geometric shapes (e.g., squares). Written production of both irregular words and nonwords engaged a left-hemisphere perisylvian network associated with reading/spelling and phonological processing skills. Effects of lexicality, manifested by increased activation during nonword relative to irregular word spelling, were noted in anterior perisylvian regions (posterior inferior frontal gyrus/operculum/precentral gyrus/insula), and in left ventral occipito-temporal cortex. In addition to enhanced neural responses within domain-specific components of the language network, the increased cognitive demands associated with spelling nonwords engaged domain-general frontoparietal cortical networks involved in selective attention and executive control. These results elucidate the neural substrates of sublexical processing during written language production and complement lesion-deficit correlation studies of phonological agraphia.

  3. Memory Consolidation and Neural Substrate of Reward

    Directory of Open Access Journals (Sweden)

    Redolar-Ripoll, Diego

    2012-08-01

    Full Text Available The aim of this report is to analyze the relationships between reward and learning and memory processes. Different studies have described how information about rewards influences behavior and how the brain uses this reward information to control learning and memory processes. Reward nature seems to be processed in different ways by neurons in different brain structures, ranging from the detection and perception of rewards to the use of information about predicted rewards for the control of goal-directed behavior. The neural substrate underling this processing of reward information is a reliable way of improving learning and memory processes. Evidence from several studies indicates that this neural system can facilitate memory consolidation in a wide variety of learning tasks. From a molecular perspective, certain cardinal features of reward have been described as forms of memory. Studies of human addicts and studies in animal models of addiction show that chronic drug exposure produces stable changes in the brain at the cellular and molecular levels that underlie the long-lasting behavioral plasticity associated with addiction. These molecular and cellular adaptations involved in addiction are also implicated in learning and memory processes. Dopamine seems to be a critical common signal to activate different genetic mechanisms that ultimately remodel synapses and circuits. Despite memory is an active and complex process mediated by different brain areas, the neural substrate of reward is able to improve memory consolidation in a several paradigms. We believe that there are many equivalent traits between reward and learning and memory processes.

  4. Interaction of Drops on a Soft Substrate

    Science.gov (United States)

    Lubbers, Luuk A.; Weijs, Joost H.; Das, Siddhartha; Botto, Lorenzo; Andreotti, Bruno; Snoeijer, Jacco H.

    2013-11-01

    A sessile drop can elastically deform a substrate by the action of capillary forces. The typical size of the deformation is given by the ratio of surface tension and the elastic modulus, γ / E , which can reach up to 10-100 microns for soft elastomers. In this talk we theoretically show that the contact angles of drops on such a surface exhibit two transitions when increasing γ / E : (i) the microsocopic geometry of the contact line first develops a Neumann-like cusp when γ / E is of the order of few nanometers, (ii) the macroscopic angle of the drop is altered only when γ / E reaches the size of the drop. Using the same framework we then show that two neighboring drops exhibit an effective interaction, mediated by the deformation of the elastic medium. This is in analogy to the well-known Cheerios effect, where small particles at a liquid interface attract eachother due to the meniscus deformations. Here we reveal the nature of drop-drop interactions on a soft substrate by combining numerical and analytical calculations.

  5. Droplet evaporation on a soluble substrate

    Science.gov (United States)

    Mailleur, Alexandra; Pirat, Christophe; Colombani, Jean; CNES Collaboration

    2015-11-01

    Stains left by evaporated droplets are ubiquitous in everyday life as well as in industrial processes. Whatever the composition of the evaporating liquid (colloidal suspensions, biological fluids...), the stains are mostly constituted by a deposit at the periphery of the dried drop, similar to a coffee stain (Deegan, 1997). All these studies have been carried with non-reacting solids. In this presentation, we focus on the behavior of a pure-water droplet evaporating on a soluble substrate which is more complex, since three phenomena are strongly interacting: the dissolution of the substrate, the diffusion/convection of the dissolved species into the drop and the evaporation of the liquid. NaCl and KCl single crystals have been chosen for this experimental study as they are fast-dissolving solids. We have observed that the dissolution induces a pinning of the triple line from the beginning of the evaporation, leading to a decrease of the contact angle in time. At the end of the evaporation, a peripheral deposit is always formed, proof of an outward flow inside the drop (coffee-ring effect). The authors would like to thank the CNES for the financial support.

  6. Agaricus blazei production on non-composted substrates based on sunflower seed hulls and spent oyster mushroom substrate.

    Science.gov (United States)

    González Matute, R; Figlas, D; Curvetto, N

    2011-06-01

    Agaricus blazei Murrill is usually cultivated using the same biphasic composting method employed for A. bisporus. Because cultivation of A. blazei on traditional A. bisporus composts poses some disadvantages, non-composted substrates were studied for A. blazei cultivation. Mycelial growth rate and productive performance of A. blazei were evaluated on substrates containing sunflower seed hulls, Pleurotus spp. spent mushroom substrate, or their combination, in the absence or in the presence of different supplements (vermicompost, peat or brewery residues). Substrates were prepared by initially soaking them and then they were sterilized (1 atm for 120 min). In addition, each substrate's degradation was measured after cultivation by obtaining the lignin, cellulose, hemicellulose, organic matter, total fiber, ash, carbon and nitrogen contents before spawn-run and at the end of two flushes of A. blazei. The cultivation of A. blazei on non-composted substrates is possible and with a low rate of contamination when using the spent mushroom substrate as the main component or combined 50:50 with sunflower seed hulls. In addition, the best yields were obtained on those substrates containing spent Pleurotus mushroom substrate with supplements and those mixtures with sunflower seed hulls and vermicompost. These yields were similar to those reported on composted substrates. Substrate changes in composition measured at the end of two flushes indicate that the lignin-hemicellulose fraction was preferentially used and that the substrates exhibiting the best yield showed greater biodegradation of lignin-hemicellulose fraction than the others did.

  7. Effect of substrate competition in kinetic models of metabolic networks.

    Science.gov (United States)

    Schäuble, Sascha; Stavrum, Anne Kristin; Puntervoll, Pål; Schuster, Stefan; Heiland, Ines

    2013-09-02

    Substrate competition can be found in many types of biological processes, ranging from gene expression to signal transduction and metabolic pathways. Although several experimental and in silico studies have shown the impact of substrate competition on these processes, it is still often neglected, especially in modelling approaches. Using toy models that exemplify different metabolic pathway scenarios, we show that substrate competition can influence the dynamics and the steady state concentrations of a metabolic pathway. We have additionally derived rate laws for substrate competition in reversible reactions and summarise existing rate laws for substrate competition in irreversible reactions.

  8. Snap-Through Instability of Graphene on Substrates

    Directory of Open Access Journals (Sweden)

    Li Teng

    2009-01-01

    Full Text Available Abstract We determine the graphene morphology regulated by substrates with herringbone and checkerboard surface corrugations. As the graphene–substrate interfacial bonding energy and the substrate surface roughness vary, the graphene morphology snaps between two distinct states: (1 closely conforming to the substrate and (2 remaining nearly flat on the substrate. Since the graphene morphology is strongly tied to the electronic properties of graphene, such a snap-through instability of graphene morphology can lead to desirable graphene electronic properties that could potentially enable graphene-based functional electronic components (e.g. nano-switches.

  9. Nemesia root hair response to paper pulp substrate for micropropagation.

    Science.gov (United States)

    Labrousse, Pascal; Delmail, David; Decou, Raphaël; Carlué, Michel; Lhernould, Sabine; Krausz, Pierre

    2012-01-01

    Agar substrates for in vitro culture are well adapted to plant micropropagation, but not to plant rooting and acclimatization. Conversely, paper-pulp-based substrates appear as potentially well adapted for in vitro culture and functional root production. To reinforce this hypothesis, this study compares in vitro development of nemesia on several substrates. Strong differences between nemesia roots growing in agar or in paper-pulp substrates were evidenced through scanning electron microscopy. Roots developed in agar have shorter hairs, larger rhizodermal cells, and less organized root caps than those growing on paper pulp. In conclusion, it should be noted that in this study, in vitro microporous substrates such as paper pulp lead to the production of similar root hairs to those found in greenhouse peat substrates. Consequently, if agar could be used for micropropagation, rooting, and plant acclimatization, enhancement could be achieved if rooting stage was performed on micro-porous substrates such as paper pulp.

  10. An Analytical Model for Spectral Peak Frequency Prediction of Substrate Noise in CMOS Substrates

    DEFF Research Database (Denmark)

    Shen, Ming; Mikkelsen, Jan H.

    2013-01-01

    This paper proposes an analytical model describing the generation of switching current noise in CMOS substrates. The model eliminates the need for SPICE simulations in existing methods by conducting a transient analysis on a generic CMOS inverter and approximating the switching current waveform us...

  11. Automatic classification of blank substrate defects

    Science.gov (United States)

    Boettiger, Tom; Buck, Peter; Paninjath, Sankaranarayanan; Pereira, Mark; Ronald, Rob; Rost, Dan; Samir, Bhamidipati

    2014-10-01

    Mask preparation stages are crucial in mask manufacturing, since this mask is to later act as a template for considerable number of dies on wafer. Defects on the initial blank substrate, and subsequent cleaned and coated substrates, can have a profound impact on the usability of the finished mask. This emphasizes the need for early and accurate identification of blank substrate defects and the risk they pose to the patterned reticle. While Automatic Defect Classification (ADC) is a well-developed technology for inspection and analysis of defects on patterned wafers and masks in the semiconductors industry, ADC for mask blanks is still in the early stages of adoption and development. Calibre ADC is a powerful analysis tool for fast, accurate, consistent and automatic classification of defects on mask blanks. Accurate, automated classification of mask blanks leads to better usability of blanks by enabling defect avoidance technologies during mask writing. Detailed information on blank defects can help to select appropriate job-decks to be written on the mask by defect avoidance tools [1][4][5]. Smart algorithms separate critical defects from the potentially large number of non-critical defects or false defects detected at various stages during mask blank preparation. Mechanisms used by Calibre ADC to identify and characterize defects include defect location and size, signal polarity (dark, bright) in both transmitted and reflected review images, distinguishing defect signals from background noise in defect images. The Calibre ADC engine then uses a decision tree to translate this information into a defect classification code. Using this automated process improves classification accuracy, repeatability and speed, while avoiding the subjectivity of human judgment compared to the alternative of manual defect classification by trained personnel [2]. This paper focuses on the results from the evaluation of Automatic Defect Classification (ADC) product at MP Mask

  12. The structural neural substrate of subjective happiness.

    Science.gov (United States)

    Sato, Wataru; Kochiyama, Takanori; Uono, Shota; Kubota, Yasutaka; Sawada, Reiko; Yoshimura, Sayaka; Toichi, Motomi

    2015-11-20

    Happiness is a subjective experience that is an ultimate goal for humans. Psychological studies have shown that subjective happiness can be measured reliably and consists of emotional and cognitive components. However, the neural substrates of subjective happiness remain unclear. To investigate this issue, we used structural magnetic resonance imaging and questionnaires that assessed subjective happiness, the intensity of positive and negative emotional experiences, and purpose in life. We found a positive relationship between the subjective happiness score and gray matter volume in the right precuneus. Moreover, the same region showed an association with the combined positive and negative emotional intensity and purpose in life scores. Our findings suggest that the precuneus mediates subjective happiness by integrating the emotional and cognitive components of happiness.

  13. Polycrystalline Silicon ISFETs on Glass Substrate

    Directory of Open Access Journals (Sweden)

    Hiroshi Maeda

    2005-05-01

    Full Text Available The Ion Sensitive Field Effect Transistor (ISFET operation based onpolycrystalline silicon thin film transistors is reported. These devices can be fabricated oninexpensive disposable substrates such as glass or plastics and are, therefore, promisingcandidates for low cost single-use intelligent multisensors. In this work we have developedan extended gate structure with PE-CVD Si3N4 deposited on top of a conductor, which alsoprovides the electrical connection to the remote TFT gate. Nearly ideal pH sensitivity(54 mV/pH and stable operation have been achieved. Temperature effects have also beencharacterized. A penicillin sensor has been fabricated by functionalizing the sensing areawith penicillinase. The shift increases almost linearly upon the increase of penicillinconcentration until saturation is reached for ~ 7 mM. Poly-Si TFT structures with a goldsensing area have been also successfully applied to field-effect detection of DNA.

  14. Substrate Strengthening of CVD Coated Steels

    Institute of Scientific and Technical Information of China (English)

    O.Kessler; M.Heidkamp; F.Hoffmann; P.Mayr

    2004-01-01

    Properties of components and tools can be improved by the combination of coating and heat treatment processes due to the addition of single process advantages and due to the utilization of process interactions. Several low and high alloyed, structural and tool steels (AISI 4140, 52100, H13, A2, D2, etc.) have been treated by CVD-TiN-coating plus laser beam hardening respectively carburizing plus CVD-TiN-coating. Homogeneous, dense TiN-coatings with high hardness,high compressive residual stresses and good adhesion were supported by high strength substrate surfaces. Especially CVD plus laser beam hardening offers the possibility to reduce distortion due to the small heated surface volume.

  15. Dancing droplets: Chemical space, substrates, and control

    Science.gov (United States)

    Cira, Nate; Benusiglio, Adrien; Prakash, Manu

    2015-11-01

    Previously we showed that droplets of propylene glycol and water display remarkable properties when placed on clean glass due to an interplay between surface tension and evaporation. (Cira, Benusiglio, Prakash: Nature, 2015). We showed that these mechanisms apply to a range of two-component mixtures of miscible liquids where one component has both higher surface tension and higher vapor pressure on a variety of high energy surfaces. We now show how this rule can be cheated using a simple trick. We go on to demonstrate applications for cleaning, and show how this system works on substrates prepared only with sunlight. We finish by demonstrating active control of droplets, allowing access to a host of new possibilities.

  16. Screen printed UHF antennas on flexible substrates

    Science.gov (United States)

    Janeczek, Kamil; Młożniak, Anna; Kozioł, Grażyna; Araźna, Aneta; Jakubowska, Małgorzata; Bajurko, Paweł

    2010-09-01

    Printed electronics belongs to the most important developing electronics technologies. It provides new possibilities to produce low cost and large area devices. In its range several applications can be distinguished like printed batteries, OLED, biosensors, photovoltaic cells or RFID tags. In the presented investigation, antennas working in UHF frequency range were elaborated. It can be applied in the future for flexible RFID tags. To produce these antennas polymer paste with silver flakes was used. It was deposited on two flexible substrates (foil and photo paper) with screen printing techniques. After printing process surface profile, electrical and microwave parameters of performed antennas were measured using digital multimeter and network analyzer, relatively. Furthermore, a thickness of printed layers was measured.

  17. Somatosensory substrates of flight control in bats.

    Science.gov (United States)

    Marshall, Kara L; Chadha, Mohit; deSouza, Laura A; Sterbing-D'Angelo, Susanne J; Moss, Cynthia F; Lumpkin, Ellen A

    2015-05-12

    Flight maneuvers require rapid sensory integration to generate adaptive motor output. Bats achieve remarkable agility with modified forelimbs that serve as airfoils while retaining capacity for object manipulation. Wing sensory inputs provide behaviorally relevant information to guide flight; however, components of wing sensory-motor circuits have not been analyzed. Here, we elucidate the organization of wing innervation in an insectivore, the big brown bat, Eptesicus fuscus. We demonstrate that wing sensory innervation differs from other vertebrate forelimbs, revealing a peripheral basis for the atypical topographic organization reported for bat somatosensory nuclei. Furthermore, the wing is innervated by an unusual complement of sensory neurons poised to report airflow and touch. Finally, we report that cortical neurons encode tactile and airflow inputs with sparse activity patterns. Together, our findings identify neural substrates of somatosensation in the bat wing and imply that evolutionary pressures giving rise to mammalian flight led to unusual sensorimotor projections.

  18. Somatosensory Substrates of Flight Control in Bats

    Directory of Open Access Journals (Sweden)

    Kara L. Marshall

    2015-05-01

    Full Text Available Flight maneuvers require rapid sensory integration to generate adaptive motor output. Bats achieve remarkable agility with modified forelimbs that serve as airfoils while retaining capacity for object manipulation. Wing sensory inputs provide behaviorally relevant information to guide flight; however, components of wing sensory-motor circuits have not been analyzed. Here, we elucidate the organization of wing innervation in an insectivore, the big brown bat, Eptesicus fuscus. We demonstrate that wing sensory innervation differs from other vertebrate forelimbs, revealing a peripheral basis for the atypical topographic organization reported for bat somatosensory nuclei. Furthermore, the wing is innervated by an unusual complement of sensory neurons poised to report airflow and touch. Finally, we report that cortical neurons encode tactile and airflow inputs with sparse activity patterns. Together, our findings identify neural substrates of somatosensation in the bat wing and imply that evolutionary pressures giving rise to mammalian flight led to unusual sensorimotor projections.

  19. Substrate Market. Compilation and analysis of substrate market; Substratmarknadsanalys. Sammanstaellning och analys av substratmarknaden

    Energy Technology Data Exchange (ETDEWEB)

    Holgersson, Pernilla (SP Sveriges Tekniska Forskningsinstitut (Sweden)); Newborg, Aase; Hellstroem, Chris (Kan Energi Sweden AB (Sweden)); Mc Cann, Michael; Oestervall, Sara Linnea (Vattenfall Power Consultant AB (Sweden)); Fagerstroem, Erik (Lund Univ., Faculty of Engineering, LTH (Sweden)); Thomten, Maria (Swedish Univ. of Agricultural Sciences (Sweden))

    2011-10-15

    A great potential exists to produce more biogas from anaerobic digestion in Sweden and local authorities are working to develop the required production, distribution and retail systems to aid the realisation of such potential. Vaestra Goetaland, which lies on the west coast of Sweden, has a goal to produce 1,2 TWh of biogas each year by 2020 and by 2013, intends to produce 0,3 TWh each year. Skaane in the south of Sweden, has a similar goal to produce 1,4 TWh of biogas each year by 2020. The goal of the project for which this study was initiated, is to define the regional market for biogas substrate in order to determine current supply and demand and predict supply and demand in 2020. The individual substrate types that are included in this study are organic domestic waste (household, restaurants and other food retail), industrial waste products, and animal manure from agriculture. Crops are not included in the study, nor is sewage sludge. Biogas produced via biomass gasification is also not covered. The geographical limit of the study is set to cover biogas plants in Skaane, Halland och Vaestra Goetaland as well as Vaermland, Oerebro, Joenkoeping, Kronoberg and Blekinge. A series of interviews carried out with personnel from the biogas plants reveal that 70 % of the plants experience competition for substrate material. Animal slaughter waste is much sought after for use in Co-digestion plants in Skaane and Halland whereas only one plant in Vaestra Goetaland uses such waste. Plant owners revealed that plants in Vaestra Goetaland use between 50% and 100% organic domestic waste. None of the contacted plants in Vaestra Goetaland use animal manure whereas for biogas plants in Skaane and Halland, use of manure varies between 8% and 80%. The interview results show that waste fired power plants are a considerable competitor for substrate originating from the food industry waste. Competition for substrate has increased over recent years especially for those substrates

  20. Wetting on a deformable substrate with finite deformations and asymmetrical substrate surface energies

    Science.gov (United States)

    Limat, Laurent; de Pascalis, Riccardo; Dervaux, Julien; Ionescu, Ioan; Perthame, Benoit

    2016-11-01

    Wetting on soft compounds is still imperfectly understood, especially when the dry and wetted parts of the substrate have two different values of surface energies (contact angle different than 90 degrees). The problem is made very complex by geometrical non-linearities arising from finite slope of the substrate and finite deformations, that must be absolutely considered, to distinguish at second order between Young law and Neuman equilibrium of surface tensions. We have developed a numerical, finite element, code that allows one to minimize surface and bulk energies, with finite deformations and asymmetry of the surface energies. The results are compared to a linear theory based on Green function theory and Fredholm integrals, and with recent experiments using X-ray visualization. The non-linear numerics reproduce very well the observed profiles, while the linear approach gives helpful analytical approximates.

  1. Effect of substrate offcut on AlGaN/GaN HFET structures on bulk GaN substrates

    Science.gov (United States)

    Leach, J. H.; Biswas, N.; Paskova, T.; Preble, E. A.; Evans, K. R.; Wu, M.; Ni, X.; Li, X.; Özgür, Ü.; Morkoç, H.

    2011-02-01

    Bulk GaN substrates promise to bring the full potential of nitride-based devices to bear since they offer a low thermal and lattice mismatched alternative to foreign substrates for epitaxial growth. However, due to the high cost and low availability of bulk GaN substrates, effects such as surface misorientation (offcut), surface polishing, and preparation of such substrates on subsequent epitaxy are still not well understood. As such, AlGaN/GaN heterostructures with nominal Al compositions of 25% were grown by MOCVD on semi-insulating bulk GaN substrates with offcuts ranging from 0.05 to 1.95° in the m-direction (10 10) to attempt to determine the optimal offcut for bulk GaN substrates for AlGaN-based HFET devices. X-ray diffraction (XRD) studies indicate that the Al composition does not vary with offcut, however reciprocal space mapping shows evidence of strain relaxation of the AlGaN in samples grown on substrates with offcut >1.1°. Additionally, we observed a minimum in sheet resistance of the 2DEGs for substrates with offcuts near 0.5°, arising from higher mobilities in these samples. Evidence of an optimal substrate misorientation is important for AlGaN-based devices grown on bulk GaN substrates.

  2. Substrate size mediates thermal stress in the rocky intertidal.

    Science.gov (United States)

    Gedan, Keryn B; Bernhardt, Joanna; Bertness, Mark D; Leslie, Heather M

    2011-03-01

    Variation in physical factors, such as slope, orientation, and wind exposure, shapes thermal conditions. Variation in substrate size is common in many habitats, but its thermal consequences for organisms are not well characterized. Larger substrates should remain more thermally stable and act as thermal refuges for associated organisms during short, thermally stressful periods such as midday temperature peaks or tidal exposure. In observations and a transplant and thermal integration experiment, we found that larger rock substrates stayed cooler and facilitated greater survival of the barnacle Semibalanus balanoides in the high intertidal relative to small substrates during the hot summer months in southern New England, USA. However, in thermally benign northern New England, rock substrate size had no effect on barnacle distributions, indicating that the thermal effects of substrate size are mediated by regional climate.

  3. Monitoring of changes in substrate characteristics during mushroom compost production.

    Science.gov (United States)

    Lyons, Gary A; Sharma, H S Shekhar; Kilpatrick, Mairead; Cheung, Linda; Moore, Solveig

    2006-06-28

    Substrates from three mushroom compost facilities in Northern Ireland, employing similar production technologies, were examined to assess the quality of the compost produced. Biochemical investigation highlighted changes in substrates through each step of the production cycle. Thermogravimetric analysis (TGA) provided useful information on fiber fraction content and extent of substrate breakdown. A comparison of productivity, chemical, and thermal data permitted assessment of the degree of bioconversion that had occurred in the decomposition from raw materials to finished substrate for each composter. One of the composters consistently produced substrate of inferior quality compared to the other two, indicating production inefficiencies during composting. Results demonstrated that allied to chemical analyses, TGA is a useful tool, providing valuable information on substrate quality and, in particular, for studying the bioconversion of lignocellulosic materials in mushroom compost.

  4. Substrate-mediated zero backscattering from dielectric metasurfaces

    CERN Document Server

    Petrov, Mihail; Baryshnikova, Kseniia; Belov, Pavel

    2015-01-01

    In this work, we study optical properties of all-dielectric metasurfaces on top of the high-index substrate. We show that matching the magnitudes and setting the {\\pi}-phase difference of the electric and magnetic dipole moments in nanoparticles, one can obtain a suppression of reflection from the substrate coated with metasurface. In contrast to homogeneous environment, where zero backscattering, or Kerker effect, is observed when electric and magnetic moments are in-phase, the blooming of the substrate occurs when the out-of-phase condition is satisfied, i.e. for the wavelength between the resonances of electric and magnetic dipole moments. We perform numerical simulations of spherical and disk nanoparticle arrays for different permittivities of the substrate, and confirm our model by numerically separating the contributions into the total reflection from nanoparticle arrays and bare substrate. The influence of high-index substrate is crucial for designing optical metasurfaces and photovoltaic elements with...

  5. Chemometrics approach to substrate development, case: semisyntetic cheese

    DEFF Research Database (Denmark)

    Nielsen, Per Væggemose; Hansen, Birgitte Vedel

    1998-01-01

    In several cases a well defined, robust and easy reproducible substrate that meets specific requirements is needed. This is the case in studies of fungal growth and metabolism on specific products as affected by environmental conditions or processing factors, or isolation of product specific fungi...... from food production facilities.The Chemometrics approach to substrate development is illustrated by the development of a semisyntetic cheese substrate. Growth, colour formation and mycotoxin production of 6 cheese related fungi were studied on 9 types of natural cheeses and 24 synthetic cheese...... substrates and compared using principal component analysis (PCA). The synthetic cheese substrates contained various amounts of Ca, K, Mg, Na, P, Fe, Cu, Zn, lactate, lactose and casein. In this manner a robust, well-defined and easy prepared laboratory cheese substrate was developed for Penicillium commune...

  6. Micro Embossing of Ceramic Green Substrates for Micro Devices

    CERN Document Server

    Shan, X -C; Maw, H P; Lu, C W; Lam, Y C

    2008-01-01

    Multilayered ceramic substrates with embedded micro patterns are becoming increasingly important, for example, in harsh environment electronics and microfluidic devices. Fabrication of these embedded micro patterns, such as micro channels, cavities and vias, is a challenge. This study focuses on the process of patterning micro features on ceramic green substrates using micro embossing. A ceramic green tape that possessed near-zero shrinkage in the x-y plane was used, six layers of which were laminated as the embossing substrate. The process parameters that impact on the pattern fidelity were investigated and optimized in this study. Micro features with line-width as small as several micrometers were formed on the ceramic green substrates. The dynamic thermo-mechanical analysis indicated that extending the holding time at certain temperature range would harden the green substrates with little effect on improving the embossing fidelity. Ceramic substrates with embossed micro patterns were obtain d after co-firi...

  7. Experimental analysis of green roof substrate detention characteristics.

    Science.gov (United States)

    Yio, Marcus H N; Stovin, Virginia; Werdin, Jörg; Vesuviano, Gianni

    2013-01-01

    Green roofs may make an important contribution to urban stormwater management. Rainfall-runoff models are required to evaluate green roof responses to specific rainfall inputs. The roof's hydrological response is a function of its configuration, with the substrate - or growing media - providing both retention and detention of rainfall. The objective of the research described here is to quantify the detention effects due to green roof substrates, and to propose a suitable hydrological modelling approach. Laboratory results from experimental detention tests on green roof substrates are presented. It is shown that detention increases with substrate depth and as a result of increasing substrate organic content. Model structures based on reservoir routing are evaluated, and it is found that a one-parameter reservoir routing model coupled with a parameter that describes the delay to start of runoff best fits the observed data. Preliminary findings support the hypothesis that the reservoir routing parameter values can be defined from the substrate's physical characteristics.

  8. On the mechanism of substrate/non-substrate recognition by P-glycoprotein.

    Science.gov (United States)

    Mukhametov, Azat; Raevsky, Oleg A

    2017-01-01

    P-Glycoprotein (P-gp, multi-drug resistance protein, MDR1) plays a gatekeeper role, interfering delivery of multiple pharmaceuticals to the target tissues and cells. We performed Molecular Dynamics (MD) simulations to generate fifty side-chain variants for P-gp (PDB ID: 4Q9H-L) followed by docking of 31 drugs (0.6≤ER≤22.7) to the whole surface except the ATPase domains and the extracellular part. A selection of the most negative energy complex for each ligand followed. All compounds docked to the two areas - the main binding cavity at the top of P-gp (12.5% of compounds with ER2), and the binding sites in the middle of P-gp (87.5% of ER2). Our results show that anti-substrates (ER2) might behave differently in relation to the P-gp. According to our calculations, the anti-substrates almost do not bind the main binding cavity (MBC) of P-gp and rather approach the other binding sites on the protein; the substrates preferably bind the MBC; the intermediate compounds with 1≤ER≤2 bind both MBC and other binding sites almost equally. The modelling results are in line with the known hypothesis that binding the MBC is prerequisite for the pumping the compound off the P-gp.

  9. Polymer Substrates For Lightweight, Thin-Film Solar Cells

    Science.gov (United States)

    Lewis, Carol R.

    1993-01-01

    Substrates survive high deposition temperatures. High-temperature-resistant polymers candidate materials for use as substrates of lightweight, flexible, radiation-resistant solar photovoltaic cells. According to proposal, thin films of copper indium diselenide or cadmium telluride deposited on substrates to serve as active semiconductor layers of cells, parts of photovoltaic power arrays having exceptionally high power-to-weight ratios. Flexibility of cells exploited to make arrays rolled up for storage.

  10. Method for electrostatic deposition of graphene on a substrate

    Science.gov (United States)

    Sumanasekera, Gamini (Inventor); Sidorov, Anton N. (Inventor); Ouseph, P. John (Inventor); Yazdanpanah, Mehdi M. (Inventor); Cohn, Robert W. (Inventor); Jalilian, Romaneh (Inventor)

    2010-01-01

    A method for electrostatic deposition of graphene on a substrate comprises the steps of securing a graphite sample to a first electrode; electrically connecting the first electrode to a positive terminal of a power source; electrically connecting a second electrode to a ground terminal of the power source; placing the substrate over the second electrode; and using the power source to apply a voltage, such that graphene is removed from the graphite sample and deposited on the substrate.

  11. Internal stress and yield strength of copper films on substrates

    Institute of Scientific and Technical Information of China (English)

    Zhang Jian-Min; Zhang Yan; Xu Ke-Wei

    2005-01-01

    Internal stress and yield strength of pure copper films on substrates were characterized by x-ray diffraction and thermal-cycle substrate curvature methods. The internal stress was of tension, and decreased with increasing workinggas (argon) pressure and increased with increasing film thickness. Tensile yield strength of copper films on steel substrate was reciprocal to the film thickness. Similarly, the compressive yield strength depended strongly on the film thickness:the thinner the film thickness, the larger the compressive yield strength.

  12. Collective Movement of Epithelial Cells on a Collagen Gel Substrate

    OpenAIRE

    Haga, Hisashi; Irahara, Chikako; KOBAYASHI, Ryo; Nakagaki, Toshiyuki; Kawabata, Kazushige

    2004-01-01

    Collective cell movement acts as an efficient strategy in many physiological events, including wound healing, embryonic development, and morphogenesis. We found that epithelial cells (Madin-Darby canine kidney cell) migrated collectively along one direction on a collagen gel substrate. Time-lapse images of Madin-Darby canine kidney cells cultured on type-I collagen gels and glass substrates were captured by phase contrast microscopy equipped with an incubation system. On the gel substrate, th...

  13. Substrate Effects in Wideband SiGe HBT Mixer Circuits

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Vidkjær, Jens; Krozer, Viktor

    2005-01-01

    In this paper, the influence from substrate effects on the performance of wideband SiGe HBT mixer circuits is investigated. Equivalent circuit models including substrate networks are extracted from on-wafer test structures and compared with electromagnetic simulations. Electromagnetic simulations...... are also applied to predict short distance substrate coupling effects. Simulation results using extracted equivalent circuit models and substrate coupling networks are compared with experimental results obtained on a wideband mixer circuit implemented in a 0.35 μm, 60 GHz ft SiGe HBT BiCMOS process....

  14. Buckling modes of elastic thin films on elastic substrates

    Science.gov (United States)

    Mei, Haixia; Huang, Rui; Chung, Jun Young; Stafford, Christopher M.; Yu, Hong-Hui

    2007-04-01

    Two buckling modes have been observed in thin films: buckle delamination and wrinkling. This letter identifies the conditions for selecting the favored buckling modes for elastic films on elastic substrates. Transition from one buckling mode to another is predicted as the stiffness ratio between the substrate and the film or is predicted for variation of the stiffness ratio between the substrate and the film or variation of theinterfacial defect size. The theoretical results are demonstrated experimentally by observing the coexistence of both buckling modes and mode transition in one film-substrate system.

  15. Friction and Shear Strength at the Nanowire–Substrate Interfaces

    Directory of Open Access Journals (Sweden)

    Gu Yi

    2009-01-01

    Full Text Available Abstract The friction and shear strength of nanowire (NW–substrate interfaces critically influences the electrical/mechanical performance and life time of NW-based nanodevices. Yet, very few reports on this subject are available in the literature because of the experimental challenges involved and, more specifically no studies have been reported to investigate the configuration of individual NW tip in contact with a substrate. In this letter, using a new experimental method, we report the friction measurement between a NW tip and a substrate for the first time. The measurement was based on NW buckling in situ inside a scanning electron microscope. The coefficients of friction between silver NW and gold substrate and between ZnO NW and gold substrate were found to be 0.09–0.12 and 0.10–0.15, respectively. The adhesion between a NW and the substrate modified the true contact area, which affected the interfacial shear strength. Continuum mechanics calculation found that interfacial shear strengths between silver NW and gold substrate and between ZnO NW and gold substrate were 134–139 MPa and 78.9–95.3 MPa, respectively. This method can be applied to measure friction parameters of other NW–substrate systems. Our results on interfacial friction and shear strength could have implication on the AFM three-point bending tests used for nanomechanical characterisation.

  16. Sol-gel derived ceramic electrolyte films on porous substrates

    Energy Technology Data Exchange (ETDEWEB)

    Kueper, T.W.

    1992-05-01

    A process for the deposition of sol-gel derived thin films on porous substrates has been developed; such films should be useful for solid oxide fuel cells and related applications. Yttria-stabilized zirconia films have been formed from metal alkoxide starting solutions. Dense films have been deposited on metal substrates and ceramic substrates, both dense and porous, through dip-coating and spin-coating techniques, followed by a heat treatment in air. X-ray diffraction has been used to determine the crystalline phases formed and the extent of reactions with various substrates which may be encountered in gas/gas devices. Surface coatings have been successfully applied to porous substrates through the control of substrate pore size and deposition parameters. Wetting of the substrate pores by the coating solution is discussed, and conditions are defined for which films can be deposited over the pores without filling the interiors of the pores. Shrinkage cracking was encountered in films thicker than a critical value, which depended on the sol-gel process parameters and on the substrate characteristics. Local discontinuities were also observed in films which were thinner than a critical value which depended on the substrate pore size. A theoretical discussion of cracking mechanisms is presented for both types of cracking, and the conditions necessary for successful thin formation are defined. The applicability of these film gas/gas devices is discussed.

  17. Composite single crystal silicon scan mirror substrates Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Single crystal silicon is a desirable mirror substrate for scan mirrors in space telescopes. As diameters of mirrors become larger, existing manufacturing...

  18. A meta-substrate to enhance the bandwidth of metamaterials.

    Science.gov (United States)

    Chen, Hongsheng; Wang, Zuojia; Zhang, Runren; Wang, Huaping; Lin, Shisheng; Yu, Faxin; Moser, Herbert O

    2014-06-12

    We propose the concept of a meta-substrate to broaden the bandwidth of left-handed metamaterials. The meta-substrate, which behaves like an inhomogeneous magnetic substrate, is composed of another kind of magnetic metamaterials like metallic closed rings. When conventional metamaterial rings are printed on this kind of meta-substrate in a proper way, the interaction of the metamaterials units can be greatly enhanced, yielding an increased bandwidth of negative permeability. An equivalent circuit analytical model is used to quantitatively characterize this phenomenon. Both numerical and experimental demonstrations are carried out, showing good agreement with theoretical predictions.

  19. Enhanced 3D fluorescence live cell imaging on nanoplasmonic substrate

    Energy Technology Data Exchange (ETDEWEB)

    Gartia, Manas Ranjan [Department of Nuclear, Plasma and Radiological Engineering, University of Illinois, Urbana, IL 61801 (United States); Hsiao, Austin; Logan Liu, G [Department of Bioengineering, University of Illinois, Urbana, IL 61801 (United States); Sivaguru, Mayandi [Institute for Genomic Biology, University of Illinois, Urbana, IL 61801 (United States); Chen Yi, E-mail: loganliu@illinois.edu [Department of Electrical and Computer Engineering, University of Illinois, Urbana, IL 61801 (United States)

    2011-09-07

    We have created a randomly distributed nanocone substrate on silicon coated with silver for surface-plasmon-enhanced fluorescence detection and 3D cell imaging. Optical characterization of the nanocone substrate showed it can support several plasmonic modes (in the 300-800 nm wavelength range) that can be coupled to a fluorophore on the surface of the substrate, which gives rise to the enhanced fluorescence. Spectral analysis suggests that a nanocone substrate can create more excitons and shorter lifetime in the model fluorophore Rhodamine 6G (R6G) due to plasmon resonance energy transfer from the nanocone substrate to the nearby fluorophore. We observed three-dimensional fluorescence enhancement on our substrate shown from the confocal fluorescence imaging of chinese hamster ovary (CHO) cells grown on the substrate. The fluorescence intensity from the fluorophores bound on the cell membrane was amplified more than 100-fold as compared to that on a glass substrate. We believe that strong scattering within the nanostructured area coupled with random scattering inside the cell resulted in the observed three-dimensional enhancement in fluorescence with higher photostability on the substrate surface.

  20. Substrate use and selection in sympatric intertidal hermit crab species

    Directory of Open Access Journals (Sweden)

    A. TURRA

    Full Text Available Coexisting hermit crabs may competitively interact for shells and microhabitats, mainly when shell availability is habitat-related. Three species of Clibanarius (C. antillensis, C. sclopetarius, and C. vittatus coexist in the intertidal region of Pernambuco Islet, Araçá Region, São Sebastião Channel, southeastern Brazil. This study evaluated crab preferences for four substrate types used by these species in nature (rocky shore, pebbles, sand, and mud in allopatric (single species and sympatric (three species treatments in simulations of high tide and low tide. The substrate preference of the three hermit crabs did not vary between low and high tide situations. At low tide the crabs either moved into holes in the highly complex rocky substrate or buried themselves in mud. Substrate selection may explain the patterns of substrate use in nature only for C. vittatus. Clibanarius antillensis and C. sclopetarius showed closer similarities in the pattern of substrate selection in the sympatric treatment with the substrate use in nature than in allopatric treatment, indicating a positive influence (dependence of the presence of one species on the presence of another. Use of sub-optimal substrates, mainly by C. antillensis, may be caused by other factors such as its low desiccation tolerances. If competition for space takes place among these species, it would be more intense between C. sclopetarius and C. vittatus given their higher overlap in substrate preference than between them and C. antillensis.

  1. Effect of the silicon substrate structure on chip spiral inductor

    Institute of Scientific and Technical Information of China (English)

    Chunlai XUE; Fei YAO; Buwen CHENG; Qiming WANG

    2008-01-01

    In this paper, the effect of the substrate structure on the performance of the spiral inductor is investigated by the 3-D electromagnetic simulator, Ansoft high frequency structure simulator (HFSS). With variations in the substrate structure including substrate conductivity, permittivity and thickness of the dielectric layer, the performance of the inductors has been analyzed in detail. The simulation results and analyses indicate that the performance of the spiral inductor can be mostly improved by lowering the conductivity of the substrate, increasing the thickness of the dielectric layer and using the low K dielectric layer. In the mean time, some guidelines or "design rules" are summarized by the results of this study.

  2. Phase Diagrams of Instabilities in Compressed Film-Substrate Systems.

    Science.gov (United States)

    Wang, Qiming; Zhao, Xuanhe

    2014-05-01

    Subject to a compressive membrane stress, an elastic film bonded on a substrate can become unstable, forming wrinkles, creases or delaminated buckles. Further increasing the compressive stress can induce advanced modes of instabilities including period-doubles, folds, localized ridges, delamination, and coexistent instabilities. While various instabilities in film-substrate systems under compression have been analyzed separately, a systematic and quantitative understanding of these instabilities is still elusive. Here we present a joint experimental and theoretical study to systematically explore the instabilities in elastic film-substrate systems under uniaxial compression. We use the Maxwell stability criterion to analyze the occurrence and evolution of instabilities analogous to phase transitions in thermodynamic systems. We show that the moduli of the film and the substrate, the film-substrate adhesion strength, the film thickness, and the prestretch in the substrate determine various modes of instabilities. Defects in the film-substrate system can facilitate it to overcome energy barriers during occurrence and evolution of instabilities. We provide a set of phase diagrams to predict both initial and advanced modes of instabilities in compressed film-substrate systems. The phase diagrams can be used to guide the design of film-substrate systems to achieve desired modes of instabilities.

  3. A caged substrate peptide for matrix metalloproteinases.

    Science.gov (United States)

    Decaneto, Elena; Abbruzzetti, Stefania; Heise, Inge; Lubitz, Wolfgang; Viappiani, Cristiano; Knipp, Markus

    2015-02-01

    Based on the widely applied fluorogenic peptide FS-6 (Mca-Lys-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2; Mca = methoxycoumarin-4-acetyl; Dpa = N-3-(2,4-dinitrophenyl)l-α,β-diaminopropionyl) a caged substrate peptide Ac-Lys-Pro-Leu-Gly-Lys*-Lys-Ala-Arg-NH2 (*, position of the cage group) for matrix metalloproteinases was synthesized and characterized. The synthesis implies the modification of a carbamidated lysine side-chain amine with a photocleavable 2-nitrobenzyl group. Mass spectrometry upon UV irradiation demonstrated the complete photolytic cleavage of the protecting group. Time-resolved laser-flash photolysis at 355 nm in combination with transient absorption spectroscopy determined the biphasic decomposition with τa = 171 ± 3 ms (79%) and τb = 2.9 ± 0.2 ms (21%) at pH 6.0 of the photo induced release of the 2-nitrobenzyl group. The recombinantly expressed catalytic domain of human membrane type I matrix metalloproteinase (MT1-MMP or MMP-14) was used to determine the hydrolysis efficiency of the caged peptide before and after photolysis. It turned out that the cage group sufficiently shields the peptide from peptidase activity, which can be thus controlled by UV light.

  4. Polarimetric studies of polyethylene terephtalate flexible substrates

    Science.gov (United States)

    Stchakovsky, M.; Garcia-Caurel, E.; Warenghem, M.

    2008-12-01

    Polymer sheets are currently used worldwide in a wide range of applications. The manufacturing process of these sheets involves extruding machines that stretch the material in both lateral and longitudinal directions with respect to the machine direction, thus inducing birefringence. In most cases, the film obtained is optically biaxial. Polarimetric spectroscopy (Ellipsometry and Mueller Matrix) combined with conoscopic observation are the methods of choice to study these properties. In this work we report an analysis of commercially available polyethylene terephtalate (PET) films used as substrate for food packaging as well as for embedded electronic devices such as solar cells or flexible displays. Initial observation of these films through polarizing microscope in conoscopic mode reveals first the trace of optical axis plane with respect to the film surface and second, whether the optical axis is acute or not. This preliminary study allows optimal sample positioning for further polarimetric studies. The measurements and modelling are done in both reflection and transmission mode on several spectroscopic polarimetric setups from UV to NIR. The models give as a main result, the dielectric tensor of the film as well as its orientation with respect to the laboratory reference frame.

  5. Dropwise condensation on a cold gradient substrate

    Science.gov (United States)

    Macner, Ashley; Daniel, Susan; Steen, Paul

    2012-11-01

    Distributions of drops that arise from dropwise condensation evolve by nucleation, growth, and coalescence of drops. An understanding of how surface-energy gradients applied to the substrate affect drop growth and coalescence is needed for design of effective surfaces for large-scale dropwise condensation. Transient dropwise condensation from a vapor phase onto a cold and chemically treated surface is reported. The surfaces were treated to deliver either a uniform contact-angle or a gradient of contact-angles by silanization. The time evolution of drop-size and number-density distributions is reported. For a typical condensation experiment, the drop distributions advance through two stages: an increase in drop density as a result of nucleation and a decrease in drop density as a result of larger scale coalescence events. Because the experiment is transient in nature, the shape of the distribution can be used to predict the number of drop generations and their stage of development. Preliminary results for gradient surfaces will be discussed and compared against observations of behavior on uniformly coated surfaces. NASA Space Technology Research Fellowship (NSTRF).

  6. Bimodal lipid substrate dependence of phosphatidylinositol kinase.

    Science.gov (United States)

    Ganong, B R

    1990-07-24

    Phosphatidylinositol (PI) kinase activity was solubilized from rat liver microsomes and partially purified by chromatography on hydroxyapatite and Reactive Green 19-Superose. Examination of the ATP dependence using a mixed micellar assay gave a Km of 120 microM. The dependence of reaction rate on PI was more complicated. PI kinase bound a large amount of Triton X-100, and as expected for a micelle-associated enzyme utilizing a micelle-associated lipid substrate, the reaction rate was dependent on the micellar mole fraction, PI/(PI + Triton X-100), with a Km of 0.02 (unitless). Activity showed an additional dependence on bulk PI concentration at high micelle dilution. These results demonstrated two kinetically distinguishable steps leading to formation of a productive PI/enzyme(/ATP) complex. The rate of the first step, which probably represents exchange of PI from the bulk micellar pool into enzyme-containing micelles, depends on bulk PI concentration. The rate of the second step, association of PI with enzyme within a single micelle, depends on the micellar mole fraction of PI. Depression of the apparent Vmax at low ionic strength suggested that electrostatic repulsion between negatively charged PI/Triton X-100 mixed micelles inhibits PI exchange, consistent with a model in which intermicellar PI exchange depends on micellar collisions.

  7. Validation of computationally predicted substrates for laccase

    Directory of Open Access Journals (Sweden)

    Reena

    2014-10-01

    Full Text Available Present study reports the validation (oxidation of computationally predicted oxidation of xenobiotic contaminants by commercially available pure laccase from Trametes versicolor. Selected contaminants were predicted as potential targets for laccase oxidation by using in-silico docking tool. The oxidation by laccase was measured by change in absorbance at specific λ max of each compound. Sinapic acid and tyrosine were taken as positive and negative controls, respectively. Oxidation was observed in m-chlorophenol, 2,4 di-chlorophenol, 2,4,6 tri-chlorophenol, captan, atrazine and thiodicarb, except malathion, which showed no activity. It could be speculated that the predicted substrates showing oxidation shared homology at structural and chemical level with positive control compounds. In case of malathion, structural non-homology with sinapic acid could be attributed to its inactivity towards laccase that required further structural analysis. Thus, a remediation tool proposing an advanced remediation approach combining the application of theoretical in-silico method and subsequent experimental validation using pure laccase could be proposed. As number and type of xenobiotics increase, the unfeasibility to screen them experimentally for bioremediation also rise. This approach would be useful to reduce the time and cost required in other screening methods.

  8. Heat transfer simulation in solid substrate fermentation.

    Science.gov (United States)

    Saucedo-Castañeda, G; Gutiérrez-Rojas, M; Bacquet, G; Raimbault, M; Viniegra-González, G

    1990-04-01

    A mathematical model was developed and tested to simulate the generation and transfer of heat in solid substrate fermentation (SSF). The experimental studies were realized in a 1-L static bioreactor packed with cassava wet meal and inoculated with Aspergillus niger. A simplified pseudohomogeneous monodimensional dynamic model was used for the energy balance. Kinetic equations taking into account biomass formation (logistic), sugar consumption (with maintenance), and carbon dioxide formation were used. Model verification was achieved by comparison of calculated and experimental temperatures. Heat transfer was evaluated by the estimation of Biot and Peclet heat dimensionless numbers 5-10 and 2550-2750, respectively. It was shown that conduction through the fermentation fixed bed was the main heat transfer resistance. This model intends to reach a better understanding of transport phenomena in SSF, a fact which could be used to evaluate various alternatives for temperature control of SSF, i.e., changing air flow rates and increasing water content. Dimensionless numbers could be used as scale-up criteria of large fermentors, since in those ratios are described the operating conditions, geometry, and size of the bioreactor. It could lead to improved solid reactor systems. The model can be used as a basis for automatic control of SSF for the production of valuable metabolites in static fermentors.

  9. Crystal structure and substrate specificity of D-galactose-6-phosphate isomerase complexed with substrates.

    Directory of Open Access Journals (Sweden)

    Woo-Suk Jung

    Full Text Available D-Galactose-6-phosphate isomerase from Lactobacillus rhamnosus (LacAB; EC 5.3.1.26, which is encoded by the tagatose-6-phosphate pathway gene cluster (lacABCD, catalyzes the isomerization of D-galactose-6-phosphate to D-tagatose-6-phosphate during lactose catabolism and is used to produce rare sugars as low-calorie natural sweeteners. The crystal structures of LacAB and its complex with D-tagatose-6-phosphate revealed that LacAB is a homotetramer of LacA and LacB subunits, with a structure similar to that of ribose-5-phosphate isomerase (Rpi. Structurally, LacAB belongs to the RpiB/LacAB superfamily, having a Rossmann-like αβα sandwich fold as has been identified in pentose phosphate isomerase and hexose phosphate isomerase. In contrast to other family members, the LacB subunit also has a unique α7 helix in its C-terminus. One active site is distinctly located at the interface between LacA and LacB, whereas two active sites are present in RpiB. In the structure of the product complex, the phosphate group of D-tagatose-6-phosphate is bound to three arginine residues, including Arg-39, producing a different substrate orientation than that in RpiB, where the substrate binds at Asp-43. Due to the proximity of the Arg-134 residue and backbone Cα of the α6 helix in LacA to the last Asp-172 residue of LacB with a hydrogen bond, a six-carbon sugar-phosphate can bind in the larger pocket of LacAB, compared with RpiB. His-96 in the active site is important for ring opening and substrate orientation, and Cys-65 is essential for the isomerization activity of the enzyme. Two rare sugar substrates, D-psicose and D-ribulose, show optimal binding in the LacAB-substrate complex. These findings were supported by the results of LacA activity assays.

  10. Effect of substrate bias on the structural and electrical properties of sputtered Mo thin films on flexible substrates.

    Science.gov (United States)

    Xu, Jiaxiong

    2016-07-04

    The metal molybdenum (Mo) thin films deposited on flexible substrates can act as the contact electrode of flexible Cu(In,Ga)Se2 or Cu2ZnSn(S,Se)4 solar cells. In this work, in order to enhance the structural and electrical characteristics of flexible Mo thin films, a negative substrate bias was applied during the direct current sputtering of Mo thin films. The flexible substrates used for growing the Mo films were stainless steel foils and polyimides. The characteristics of Mo thin films were studied by x-ray diffraction and sheet resistance measurements. The measured results reveal that an optimal value of negative substrate bias can be found for improving the electrical and structural characteristics of Mo thin films on flexible substrates. The minimum sheet resistances of Mo thin films are 2.50 Ω/sq and 2.73 Ω/sq for the stainless steel foil and polyimide substrates, respectively.

  11. Kinetics Modelling of the Biodegradation of Benzene, Toluene and Phenol as Single Substrate and Mixed Substrate by Using Pseudomonas putida

    OpenAIRE

    Mathur, A K; Majumder, C. B.

    2010-01-01

    In the present work, kinetics of the biodegradation of benzene, toluene and phenol by using a pure culture of Pseudomonas putida (MTCC 1194) was determined by measuring the specific growth rate and degradation rate with substrate concentration as a function of time in a batch reactor. In general, the degradation rate of benzene, toluene and phenol increased with the increase in the initial substrate concentration and then decreased after reaching a maximum, showing substrate inhibition kineti...

  12. Effect of Substrate-Water Interaction on the Wetting Behavior in Water-Oil and Substrate-Water-Oil Systems

    Institute of Scientific and Technical Information of China (English)

    Yuan Yin-quan; Zou Xian-wu; Jin Zhun-zhi

    2003-01-01

    The effects of the substrate-water interaction on the wetting behavior in water-oil and surfactant-water-oil systems confined by one substrate which has the preferential interaction to one species of particles have been investigated by using the free energy analysis and discontinuous molecular dynamic simulations. As the preferential interaction between the substrate and water particles varies from small repulsion to large attraction, the partial drying, partial wetting and complete wetting state are observed in sequence. In addition, the wetting behavior of surfactant aqueous solution on the substrate is not only dependent on the interaction, but also limited by the maximum equilibrium concentration of surfactants at the interface.

  13. Effect of Substrate-Water Interaction on the Wetting Behavior in Water-Oil and Substrate-Water-Oil Systems

    Institute of Scientific and Technical Information of China (English)

    YuanYin-quan; ZouXian-wu; JinZhun-zhi

    2003-01-01

    The effects of the substrate-water interaction on the wetting behavior in water-oil and surfactant-water-oil systerns confined by one substrate which has the preferential interaction to one species of particles have been investigated by using the free energy analysis and discontinuous molecular dynamic simulations. As the preferential interaction between the substrate and water particles varies from small repulsion to large attraction, the partial drying, partial wetting and complete wetting state are observed in sequence. In addition, the wetting behavior of surfactant aqueous solution on the substrate is not only dependent on the interaction, but also limited by the maximum equilibrium concentration of surfactants at the interface.

  14. Neural substrates of time perception and impulsivity.

    Science.gov (United States)

    Wittmann, Marc; Simmons, Alan N; Flagan, Taru; Lane, Scott D; Wackermann, Jiří; Paulus, Martin P

    2011-08-11

    Several studies provide empirical evidence for the association between impulsivity and time perception. However, little is known about the neural substrates underlying this function. This investigation examined the influence of impulsivity on neural activation patterns during the encoding and reproduction of intervals with durations of 3, 9 and 18s using event-related functional magnetic resonance imaging (fMRI). Twenty-seven subjects participated in this study, including 15 high impulsive subjects that were classified based on their self-rating. FMRI activation during the duration reproduction task was correlated with measures of two self-report questionnaires related to the concept of impulsivity (Barratt Impulsiveness Scale, BIS; Zimbardo Time Perspective Inventory, ZTPI). Behaviorally, those individuals who under-reproduced temporal intervals also showed lower scores on the ZTPI future perspective subscale and higher scores on the BIS. FMRI activation revealed an accumulating pattern of neural activity peaking at the end of the 9- and 18-s intervals within right posterior insula. Activations of brain regions during the reproduction phase of the timing task, such as those related to motor execution as well as to the 'core control network' - encompassing the inferior frontal and medial frontal cortices, the anterior insula as well as the inferior parietal cortex - were significantly correlated with reproduced duration, as well as with BIS and ZTPI subscales. In particular, the greater activation in these regions the shorter were the reproduced intervals, the more impulsive was an individual and the less pronounced the future perspective. Activation in the core control network, thus, may form a biological marker for cognitive time management and for impulsiveness.

  15. Microbial growth with vapor-phase substrate

    Energy Technology Data Exchange (ETDEWEB)

    Hanzel, Joanna; Thullner, Martin; Harms, Hauke [UFZ - Helmholtz Centre for Environmental Research, Department of Environmental Microbiology, Permoserstrasse 15, 04318 Leipzig (Germany); Wick, Lukas Y., E-mail: lukas.wick@ufz.de [UFZ - Helmholtz Centre for Environmental Research, Department of Environmental Microbiology, Permoserstrasse 15, 04318 Leipzig (Germany)

    2011-04-15

    Limited information exists on influences of the diffusive transport of volatile organic contaminants (VOC) on bacterial activity in the unsaturated zone of the terrestrial subsurface. Diffusion of VOC in the vapor-phase is much more efficient than in water and results in effective VOC transport and high bioavailability despite restricted mobility of bacteria in the vadose zone. Since many bacteria tend to accumulate at solid-water, solid-air and air-water interfaces, such phase boundaries are of a special interest for VOC-biodegradation. In an attempt to evaluate microbial activity toward air-borne substrates, this study investigated the spatio-temporal interplay between growth of Pseudomonas putida (NAH7) on vapor-phase naphthalene (NAPH) and its repercussion on vapor-phase NAPH concentrations. Our data demonstrate that growth rates of strain PpG7 were inversely correlated to the distance from the source of vapor-phase NAPH. Despite the high gas phase diffusivity of NAPH, microbial growth was absent at distances above 5 cm from the source when sufficient biomass was located in between. This indicates a high efficiency of suspended bacteria to acquire vapor-phase compounds and influence headspace concentration gradients at the centimeter-scale. It further suggests a crucial role of microorganisms as biofilters for gas-phase VOC emanating from contaminated groundwater or soil. - Research highlights: > Suspended bacteria have a high efficiency to degrade vapor-phase naphthalene. > Bacteria influence NAPH vapor-phase concentration gradients at centimeter-scale. > Microbial growth on vapor-phase naphthalene is inversely correlated to its source. > Bacteria are good biofilters for gas-phase NAPH emanating from contaminated sites. - Suspended bacteria have a high efficiency to degrade vapor-phase naphthalene and effectively influence vapor-phase naphthalene concentration gradients at the centimeter scale.

  16. Shared neural substrates of apraxia and aphasia.

    Science.gov (United States)

    Goldenberg, Georg; Randerath, Jennifer

    2015-08-01

    Apraxia is regularly associated with aphasia, but there is controversy whether their co-occurrence is the expression of a common basic deficit or results from anatomical proximity of their neural substrates. However, neither aphasia nor apraxia is an indivisible entity. Both diagnoses embrace diverse manifestations that may occur more or less independently from each other. Thus, the question whether apraxia is always accompanied by aphasia may lead to conflicting answers depending on which of their manifestations are considered. We used voxel based lesion symptom mapping (VLSM) for exploring communalities between lesion sites associated with aphasia and with apraxia. Linguistic impairment was assessed by the Aachen Aphasia Test (AAT) subtests naming, comprehension, repetition, written language, and Token Test. Apraxia was examined for imitation of meaningless hand and finger postures and for pantomime of tool use. There were two areas of overlap between aphasia and apraxia. Lesions in the anterior temporal lobe interfered with pantomime of tool use and with all linguistic tests. In the left inferior parietal lobe there was a large area where lesions were associated with defective imitation of hand postures and with poor scores on written language and the Token Test. Within this large area there were also two spots in supramarginal and angular gyrus where lesions were also associated with defective pantomime. We speculate that the coincidence of language impairment and defective pantomime after anterior temporal lesions is due to impaired access to semantic memory. The combination of defective imitation of hand postures with poor scores on Token Test and written language is not easily compatible with a crucial role of parietal regions for the conversion of concepts of intended actions into motor commands. It accords better with a role of left inferior parietal lobe regions for the categorical perception of spatial relationships.

  17. Psychoanatomical substrates of Bálint's syndrome

    Science.gov (United States)

    Rizzo, M; Vecera, S

    2002-01-01

    Objectives: From a series of glimpses, we perceive a seamless and richly detailed visual world. Cerebral damage, however, can destroy this illusion. In the case of Bálint's syndrome, the visual world is perceived erratically, as a series of single objects. The goal of this review is to explore a range of psychological and anatomical explanations for this striking visual disorder and to propose new directions for interpreting the findings in Bálint's syndrome and related cerebral disorders of visual processing. Methods: Bálint's syndrome is reviewed in the light of current concepts and methodologies of vision research. Results: The syndrome affects visual perception (causing simultanagnosia/visual disorientation) and visual control of eye and hand movement (causing ocular apraxia and optic ataxia). Although it has been generally construed as a biparietal syndrome causing an inability to see more than one object at a time, other lesions and mechanisms are also possible. Key syndrome components are dissociable and comprise a range of disturbances that overlap the hemineglect syndrome. Inouye's observations in similar cases, beginning in 1900, antedated Bálint's initial report. Because Bálint's syndrome is not common and is difficult to assess with standard clinical tools, the literature is dominated by case reports and confounded by case selection bias, non-uniform application of operational definitions, inadequate study of basic vision, poor lesion localisation, and failure to distinguish between deficits in the acute and chronic phases of recovery. Conclusions: Studies of Bálint's syndrome have provided unique evidence on neural substrates for attention, perception, and visuomotor control. Future studies should address possible underlying psychoanatomical mechanisms at "bottom up" and "top down" levels, and should specifically consider visual working memory and attention (including object based attention) as well as systems for identification of object

  18. Method and apparatus for depositing atomic layers on a substrate

    NARCIS (Netherlands)

    Vermeer, A.J.P.M.; Roozeboom, F.; Deelen, J. van

    2016-01-01

    Method of depositing an atomic layer on a substrate. The method comprises supplying a precursor gas from a precursor-gas supply of a deposition head that may be part of a rotatable drum. The precursor gas is provided from the precursor-gas supply towards the substrate. The method further comprises m

  19. Patterned electroplating of micrometer scale magnetic structures on glass substrates.

    NARCIS (Netherlands)

    de Vries, A.H.B.; Kanger, S.J.; Krenn, G.E.; van Driel, R.

    2004-01-01

    This paper has developed a new method of micro patterned electroplating that enables the fabrication of micrometer scale magnetic structures on glass substrates. In contrast to other methods, the process as developed here leaves the surrounding substrate area untouched: that is there is no seed laye

  20. Patterned Electroplating of Micrometer Scale Magnetic Structures on Glass Substrates

    NARCIS (Netherlands)

    Vries, de Anthony H.B.; Kanger, Johannes S.; Krenn, Bea E.; Driel, van Roel

    2004-01-01

    This paper has developed a new method of micro patterned electroplating that enables the fabrication of micrometer scale magnetic structures on glass substrates. In contrast to other methods, the process as developed here leaves the surrounding substrate area untouched: that is there is no seed laye

  1. Use of neem cake as an organic substrate component

    Science.gov (United States)

    Nursery and greenhouse growers continue to seek materials to decrease costs of plant production while maintaining environmental stewardship. Incorporation of neem cake as a substrate component could potentially impact nitrogen release as a result of altering substrate bacterial activity. The study...

  2. Multi-Substrate Terpene Synthases: Their Occurrence and Physiological Significance

    Science.gov (United States)

    Pazouki, Leila; Niinemets, Ülo

    2016-01-01

    Terpene synthases are responsible for synthesis of a large number of terpenes in plants using substrates provided by two distinct metabolic pathways, the mevalonate-dependent pathway that is located in cytosol and has been suggested to be responsible for synthesis of sesquiterpenes (C15), and 2-C-methyl-D-erythritol-4-phosphate pathway located in plastids and suggested to be responsible for the synthesis of hemi- (C5), mono- (C10), and diterpenes (C20). Recent advances in characterization of genes and enzymes responsible for substrate and end product biosynthesis as well as efforts in metabolic engineering have demonstrated existence of a number of multi-substrate terpene synthases. This review summarizes the progress in the characterization of such multi-substrate terpene synthases and suggests that the presence of multi-substrate use might have been significantly underestimated. Multi-substrate use could lead to important changes in terpene product profiles upon substrate profile changes under perturbation of metabolism in stressed plants as well as under certain developmental stages. We therefore argue that multi-substrate use can be significant under physiological conditions and can result in complicate modifications in terpene profiles. PMID:27462341

  3. Method of filling a well in a substrate

    NARCIS (Netherlands)

    Moerman, R.

    2003-01-01

    The invention relates to a method of filling a well including a channel in a substrate. In accordance with the invention liquid is applied on a substrate comprising a well on a position that does not coincide with the well, and the well after filling is sealed with a cover means, wherein liquid is a

  4. Capacitive pressure sensor in post-processing on LTCC substrates

    NARCIS (Netherlands)

    Meijerink, M.G.H.; Nieuwkoop, E.; Veninga, E.P.; Meuwissen, M.H.H.; Tijdink, M.W.W.J.

    2005-01-01

    A capacitive pressure sensor was realized by means of a post-processing step on a low temperature co-fired ceramics (LTCC) substrate. The new sensor fabrication technology allows for integration of the sensor with interface circuitry and possibly also wireless transmission circuits on LTCC substrate

  5. A structural classification of substrate-binding proteins

    NARCIS (Netherlands)

    Berntsson, Ronnie P. -A.; Smits, Sander H. J.; Schmitt, Lutz; Slotboom, Dirk-Jan; Poolman, Bert

    2010-01-01

    Substrate-binding proteins (SBP) are associated with a wide variety of protein complexes. The proteins are part of ATP-binding cassette transporters for substrate uptake, ion gradient driven transporters, DNA-binding proteins, as well as channels and receptors from both pro-and eukaryotes. A wealth

  6. Nanopore fabrication by heating au particles on ceramic substrates

    NARCIS (Netherlands)

    Vreede, de Lennart J.; Berg, van den Albert; Eijkel, Jan C.T.

    2015-01-01

    We found that gold nanoparticles, when heated to close to their melting point on substrates of amorphous SiO2 or amorphous Si3N4, move perpendicularly into the substrate. Dependent on applied temperatures, particles can become buried or leave nanopores of extreme aspect ratio (diameter congruent to

  7. Thermal Effects of the Substrate on Water Droplet Evaporation

    Science.gov (United States)

    Sobac, Benjamin; Brutin, David

    2012-11-01

    Since a few decades, the evaporation of a drop deposited onto a substrate has been subject to numerous research activities due to the increase of the range of applications underpinned by this phenomenon. However, this process today is always a challenging problem in soft matter physics due to the complexity of present couplings: fluid dynamic, physical chemistry of the substrate, heat and mass transfer. The originality of the presented experiment is to decouple the effects of wetting properties and thermal properties of the substrate. Thus, whereas we previously presented the role of wetting properties on evaporation by changing the surface energy and the roughness while maintaining the thermal properties constant thanks to nanoscale coatings on the substrate surface (B. Sobac and D. Brutin, Langmuir 27, 14999 (2011)), we investigate here the influence of the thermal properties of the substrate while keeping the wetting properties the same (B. Sobac and D. Brutin, Phys. Rev. E, underpress). We experimentally investigate the behavior of a pinned droplet evaporating into air. The influences of the substrate temperature and substrate thermal properties on the evaporation process are studied in both hydrophilic and hydrophobic conditions. Experimental data are compared to the quasi-steady diffusion-driven evaporation model assuming the isothermia of the drop at the substrate temperature. This comparison permits to highlights several thermal mechanisms linked to evaporation and their respective contributions in regard of pure mass diffusion mechanism. The range of validity of the classical evaporation model is also discussed.

  8. An aluminum resist substrate for microfabrication by LIGA.

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, James J.; Boehme, Dale R.; Hauck, Cheryl A. (Lawrence Berkeley National Laboratory, Berkeley, CA); Yang, Chu-Yeu Peter; Hunter, Luke L.; Griffiths, Stewart K.; McLean, Dorrance E.; Aigeldinger, Georg; Hekmaty, Michelle A.; Hachman, John T.; Losey, Matthew W.; Skala, Dawn M.; Korellis, John S.; Friedmann, Thomas Aquinas (Sandia National Laboratories, Albuquerque, NM); Yang, Nancy Y. C.; Lu, Wei-Yang

    2005-04-01

    Resist substrates used in the LIGA process must provide high initial bond strength between the substrate and resist, little degradation of the bond strength during x-ray exposure, acceptable undercut rates during development, and a surface enabling good electrodeposition of metals. Additionally, they should produce little fluorescence radiation and give small secondary doses in bright regions of the resist at the substrate interface. To develop a new substrate satisfying all these requirements, we have investigated secondary resist doses due to electrons and fluorescence, resist adhesion before exposure, loss of fine features during extended development, and the nucleation and adhesion of electrodeposits for various substrate materials. The result of these studies is a new anodized aluminum substrate and accompanying methods for resist bonding and electrodeposition. We demonstrate successful use of this substrate through all process steps and establish its capabilities via the fabrication of isolated resist features down to 6 {micro}m, feature aspect ratios up to 280 and electroformed nickel structures at heights of 190 to 1400 {micro}m. The minimum mask absorber thickness required for this new substrate ranges from 7 to 15 {micro}m depending on the resist thickness.

  9. Substrate Material for Holographic Emulsions Utilizing Fluorinated Polyimide Film

    Science.gov (United States)

    Gierow, Paul A. (Inventor); Clayton, William R. (Inventor); St.Clair, Anne K. (Inventor)

    1999-01-01

    A new holographic substrate utilizing flexible. optically transparent fluorinated polyimides. Said substrates have 0 extremely low birefringence which results in a high signal to noise ratio in subsequent holograms. Specific examples of said fluorinated polyimides include 6FDA+APB and 6FDA+4BDAF.

  10. Modelling anaerobic biomass growth kinetics with a substrate threshold concentration

    NARCIS (Netherlands)

    Ribes, J.; Keesman, K.J.; Spanjers, H.

    2004-01-01

    Abstract Many bacteria have been observed to stop growing below a certain substrate threshold concentration. In this study, a modification of the Monod kinetics expression has been proposed to take into account this substrate threshold concentration observed in bacterial growth. Besides the threshol

  11. The Effect of Substrate Topography on Coating Cathodic Delamination

    DEFF Research Database (Denmark)

    Weinell, Claus E.; Sørensen, Per A.; Kiil, Søren

    2011-01-01

    This article describes the effect of steel substrate topography on coating cathodic delamination. The study showed that the surface preparation can be used to control and minimize the rate of cathodic delamination. The coating should have maximum wetting properties so that substrates with high...

  12. Antigravitational Instability of Cosmic Substrate in the Newtonian Cosmology

    Institute of Scientific and Technical Information of China (English)

    CHECHIN L. M.

    2006-01-01

    @@ A new version of the forming Universe large-scale structures is proposed, based on the refuse of analyses of only the gravitational instability of the cosmological substrate. Vacuum, i.e. The dominant nonbaryonic matter in the Universe, creates the antigravitational instability of the baryonic cosmic substrate itself and causes the formation of galaxies.

  13. Development of the Enzyme-Substrate Interactions Concept Inventory

    Science.gov (United States)

    Bretz, Stacey Lowery; Linenberger, Kimberly J.

    2012-01-01

    Enzyme function is central to student understanding of multiple topics within the biochemistry curriculum. In particular, students must understand how enzymes and substrates interact with one another. This manuscript describes the development of a 15-item Enzyme-Substrate Interactions Concept Inventory (ESICI) that measures student understanding…

  14. Substrate recognition by the 2-hydroxycarboxylate transport proteins

    NARCIS (Netherlands)

    Bandell, Michael

    2000-01-01

    The object of the research described in this thesis was to identify substrate-protein interactions that provide affinity and specificity for CitPLEME from Lc.mesenteroides and MlePLALA form L.lactis. The ability of these transporters to transport substrates that differ in structure and charge implie

  15. Multi-substrate terpene synthases: their occurrence and physiological significance

    Directory of Open Access Journals (Sweden)

    Leila Pazouki

    2016-07-01

    Full Text Available Terpene synthases are responsible for synthesis of a large number of terpenes in plants using substrates provided by two distinct metabolic pathways, the mevalonate-dependent pathway that is located in cytosol and has been suggested to be responsible for synthesis of sesquiterpenes (C15, and 2-C-methyl-D-erythritol-4-phosphate pathway located in plastids and suggested to be responsible for the synthesis of hemi- (C5, mono- (C10 and diterpenes (C20. Recent advances in characterization of genes and enzymes responsible for substrate and end product biosynthesis as well as efforts in metabolic engineering have demonstrated existence of a number of multi-substrate terpene synthases. This review summarizes the progress in the characterization of such multi-substrate terpene synthases and suggests that the presence of multi-substrate use might have been significantly underestimated. Multi-substrate use could lead to important changes in terpene product profiles upon substrate profile changes under perturbation of metabolism in stressed plants as well as under certain developmental stages. We therefore argue that multi-substrate use can be significant under physiological conditions and can result in complicate modifications in terpene profiles.

  16. Lantibiotic Reductase LtnJ Substrate Selectivity Assessed with a Collection of Nisin Derivatives as Substrates.

    Science.gov (United States)

    Mu, Dongdong; Montalbán-López, Manuel; Deng, Jingjing; Kuipers, Oscar P

    2015-06-01

    Lantibiotics are potent antimicrobial peptides characterized by the presence of dehydrated amino acids, dehydroalanine and dehydrobutyrine, and (methyl)lanthionine rings. In addition to these posttranslational modifications, some lantibiotics exhibit additional modifications that usually confer increased biological activity or stability on the peptide. LtnJ is a reductase responsible for the introduction of D-alanine in the lantibiotic lacticin 3147. The conversion of L-serine into D-alanine requires dehydroalanine as the substrate, which is produced in vivo by the dehydration of serine by a lantibiotic dehydratase, i.e., LanB or LanM. In this work, we probe the substrate specificity of LtnJ using a system that combines the nisin modification machinery (dehydratase, cyclase, and transporter) and the stereospecific reductase LtnJ in Lactococcus lactis. We also describe an improvement in the production yield of this system by inserting a putative attenuator from the nisin biosynthesis gene cluster in front of the ltnJ gene. In order to clarify the sequence selectivity of LtnJ, peptides composed of truncated nisin and different mutated C-terminal tails were designed and coexpressed with LtnJ and the nisin biosynthetic machinery. In these tails, serine was flanked by diverse amino acids to determine the influence of the surrounding residues in the reaction. LtnJ successfully hydrogenated peptides when hydrophobic residues (Leu, Ile, Phe, and Ala) were flanking the intermediate dehydroalanine, while those in which dehydroalanine was flanked by one or two polar residues (Ser, Thr, Glu, Lys, and Asn) or Gly were either less prone to be modified by LtnJ or not modified at all. Moreover, our results showed that dehydrobutyrine cannot serve as a substrate for LtnJ.

  17. Wrinkling of graphene membranes supported by silica nanoparticles on substrates

    Science.gov (United States)

    Yamamoto, Mahito; Cullen, William; Fuhrer, Michael; Einstein, Theodore; Department of Physics, University of Maryland Team

    2011-03-01

    The challenging endeavor of modulating the morphology of graphene via a patterned substrate to produce a controlled deformation has great potential importance for strain engineering the electronic properties of graphene. An essential step in this direction is to understand the response of graphene to substrate features of known geometry. Here we employ silica nanoparticles with a diameter of 10-100 nm to uniformly decorate Si O2 and mica substrates before depositing graphene, to promote nanoscale modulation of graphene geometry. The morphology of graphene on this modified substrate is then characterized by atomic force spectroscopy. We find that graphene on the substrate is locally raised by the supporting nanoparticles, and wrinkling propagates radially from the protrusions to form a ridge network which links the protrusions. We discuss the dependence of the wrinkled morphology on nanoparticle diameter and graphene thickness in terms of graphene elasticity and adhesion energy. Supported by NSF-MRSEC, Grant DMR 05-20471

  18. Potassium tantalate substrates for neutron experiments on antiferromagnetic perovskite films

    Energy Technology Data Exchange (ETDEWEB)

    Christen, H M; MacDougall, G J; Kim, H-S; Kim, D H; Boatner, L A; Bennett, C J Callender; Zarestky, J L; Nagler, S E, E-mail: christenhm@ornl.gov

    2010-11-01

    For the study of antiferromagnetism in thin-film materials, neutron diffraction is a particularly important tool, especially since magnetometry experiments are often complicated by the substrate's strong diamagnetic or paramagnetic contribution. However, the substrate, by necessity, has a lattice parameter that is very similar to that of the film, and in most cases is over 1000 times more massive than the film. Therefore, even weak structural distortions in the substrate crystal may complicate the analysis of magnetic scattering from the film. Here we show that in contrast to most other perovskite substrates (including SrTiO{sub 3}, LaAlO{sub 3}, etc.), KTaO3 provides a uniquely appropriate substrate platform for magnetic diffraction experiments on epitaxial oxide films.

  19. Magnetic dipole radiation tailored by substrates: numerical investigation

    CERN Document Server

    Markovich, Dmitry L; Samusev, Anton; Belov, Pavel A; Zayats, Anatoly V

    2014-01-01

    Nanoparticles of high refractive index materials can possess strong magnetic polarizabilities and give rise to artificial magnetism in the optical spectral range. While the response of individual dielectric or metal spherical particles can be described analytically via multipole decomposition in the Mie series, the influence of substrates, in many cases present in experimental observations, requires different approaches. Here, the comprehensive numerical studies of the influence of a substrate on the spectral response of high- index dielectric nanoparticles were performed. In particular, glass, perfect electric conductor, gold, and hyperbolic metamaterial substrates were investigated. Optical properties of nanoparticles were characterized via scattering cross-section spectra, electric field profiles, and induced electric and magnetic moments. The presence of substrates was shown to introduce significant impact on particle's magnetic resonances and resonant scattering cross-sections. Variation of substrate mat...

  20. Microstructure in electrodeposited copper layers; the role of the substrate

    DEFF Research Database (Denmark)

    Rasmussen, Anette Alsted; Jensen, Jens Dahl; Horsewell, Andy

    2001-01-01

    -crystalline Ni-P layer. The evolutions of surface topography, morphology and crystallographic texture in the layers were investigated with scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction analysis, respectively. Distinct surface topographies were observed for Cu...... layers deposited on the Au and Ni-P substrates. Deposition onto the Au substrate resulted in a very smooth surface of Cu layers, whereas the Ni-P substrate caused an irregular surface for 3-microns-thick layers of Cu. The crystallographic texture in the Cu layers in the first few micrometres depended...... stongly on the crystallographic texture in the substrate. The Cu crystallites inherited the lll-orientation of the Au substrate, whilst no preferred crystallographic orientation was observed in the Cu crystallites on the nano-crystalline Ni-P substate. For Cu layers thicker than 3 microns a lll...

  1. Skeletal muscle substrate metabolism during exercise: methodological considerations

    DEFF Research Database (Denmark)

    Van Hall, Gerrit; González-Alonso, J; Sacchetti, M;

    1999-01-01

    and the respiratory exchange ratio. However, if the aim is to quantify limb or muscle metabolism, invasive measurements have to be carried out, such as the determination of blood flow, arterio-venous (a-v) difference measurements for O2 and relevant substrates, and biopsies of the active muscle. As many substrates......; (3) the use of net limb glycerol release to estimate lipolysis is probably not valid (triacylglycerol utilization by muscle), since glycerol can be metabolized in skeletal muscle; (4) the precision of blood-borne substrate concentrations during exercise measured by a-v difference is hampered since......The aim of the present article is to evaluate critically the various methods employed in studies designed to quantify precisely skeletal muscle substrate utilization during exercise. In general, the pattern of substrate utilization during exercise can be described well from O2 uptake measurements...

  2. A lithium electrode with a zinc substrate for secondary batteries

    Science.gov (United States)

    Matsuda, Y.; Morita, M.; Katsuma, H.

    1983-03-01

    Koch (1981) and Abraham (1982) have reported work concerning the development of a lithium secondary battery using an organic electrolyte. An efficient Li electrode is a vital factor in connection with the realization of the considered rechargeable batteries. In order to obtain good efficiency in charge-discharge cycling operations, it has been proposed to employ Li negative plates with metal substrates. High coulombic efficiency was achieved using an Al substrate, which forms an alloy with deposited Li during the period of charging. The present investigation is concerned with the charge-discharge characteristics of a Li electrode with a Zn substrate in propylene carbonate solution containing LiClO4 or LiBF4. It is found that the efficiency in the case of a plate with a Zn substrate, which alloys easily with deposited Li, is as high as that obtained in connection with the use of an Al substrate.

  3. Thermodynamic model of coherent island formation on vicinal substrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xu, E-mail: zhangxubetter@gmail.com; Sun, Xiao-Hong [Henan Key Laboratory of Laser and Opto-electric Information Technology, School of Information Engineering, Zhengzhou University, Zhengzhou 450052 (China); Yu, Yanguang [School of Electrical, Computer and Telecommunications Engineering, University of Wollongong, Northfields Ave, Wollongong, New South Wales 2522 (Australia); Ren, Xiaomin [State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876 (China)

    2014-04-28

    A thermodynamic model has been proposed to address the formation of coherent island on the vicinal substrate. The morphological transition from square based island to elongated based one with various substrate misorientations is described. The initial stage of nucleation and growth process of islands in Stranski–Krastanow system is studied by taking into account the elastic deformations and the change of energy in the case of two-dimensional growth mode. The theoretical analysis shows the minimum nucleation barrier of island is on the decrease with increment of substrate misorientation, which means the nucleation of island on vicinal substrate is more favorable than that on flat substrate. By using the fitting data of experimental results done by Persichetti et al., [Phys. Rev. Lett. 104, 036104 (2010) and Phys. Rev. B 82, 121309(R) (2010)], we provide a meaningful explanation of the experimental observations.

  4. Comparison of filters: Inkjet printed on PEN substrate versus a laser-etched on LCP substrate

    KAUST Repository

    Arabi, Eyad A.

    2014-10-01

    In this paper, microstrip-based bandpass filters on polyethylene naphthalate (PEN) and liquid crystal polymers (LCP) are presented to investigate the performance of filters on ultra-thin substrates. PEN (with a thickness of 120 μm) has been characterized and used for a filter for the first time. In addition to being low cost and transparent, it demonstrates comparable RF performance to LCP. The conductor losses are compared by fabricating filters with inkjet printed lines as well as laser etched copper clad LCP sheets. With 5 layers of inkjet printing, and a curing temperature below 200°C, a final silver thickness of 2 μm and conductivity of 9.6 × 106 S/m are achieved. The designs are investigated at two frequencies, 24 GHz as well as 5 GHz to assess their performance at high and low frequencies respectively. The 24 GHz inkjet printed filter shows an insertion loss of 2 dB, while the 5 GHz design gives an insertion loss of 8 dB. We find that thin substrates have a strong effect on the insertion loss of filters especially as the frequency is reduced. The same design, realized on LCP (thickness of 100 μm) through laser etching, demonstrates a very similar performance, thus verifying this finding. © 2014 European Microwave Association.

  5. Substrate Handbook for Biogas Production; Substrathandbok foer biogasproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, My; Uldal, Martina (AnoxKaldnes AB, Lund (Sweden))

    2009-02-15

    Today, co-digestion plants in Sweden treat a broad range of different substrates, of which some have not previously been used for anaerobic digestion. The major part of this organic waste derives from households, restaurants, food industries and farms. When evaluating a new substrate as feed for anaerobic digestion, several different aspects need to be taken into consideration, such as anaerobic degradability, TS/VS content, nutrient composition and risk for mechanical problems. Consequently, there is a need for practical guidelines on how to evaluate new substrates as raw materials for biogas production, including not only gas yield but also what practical and microbiological problems that may arise when the specific substrate is treated together with other substrates in the plant. The aim with this handbook is to provide a basis on how to evaluate new substrates as feed for anaerobic digestion. The intention is that this material will save time and effort for the personnel at the plant when they come in contact with new types of waste. Also, the aim is to facilitate the process of identifying new substrates within the ABP-regulation (1774/2002) and what requirements are then demanded on handling. The work with the handbook has been divided in three different parts; (1) an extensive literature study and a compilation of the achieved results, (2) interviews with personnel at most of the Swedish co-digestion plants to identify substrates and problems of interest, and (3) lab tests of selected substrates. The lab tests included Bio Methane Potential (BMP) tests as well as a simple characterization of each substrate based on fat/protein/carbohydrate content. All data origins from anaerobic digestion within the mesophilic temperature range, but the results and discussion are applicable also for thermophilic anaerobic digestion. The result of this work is a written report together with an Excel file which are to be directly used by the biogas plants as a basis in the

  6. Buckle Driven Delamination in Thin Hard Film Compliant Substrate Systems

    Science.gov (United States)

    Moody, N. R.; Reedy, E. D.; Corona, E.; Adams, D. P.; Kennedy, M. S.; Cordill, M. J.; Bahr, D. F.

    2010-06-01

    Deformation and fracture of thin films on compliant substrates are key factors constraining the performance of emerging flexible substrate devices. [1-3] These systems often contain layers of thin polymer, ceramic and metallic films and stretchable interconnects where differing properties induce high normal and shear stresses. [4] As long as the films remain bonded to the substrates, they may deform far beyond their freestanding form. Once debonded, substrate constraint disappears leading to film failure. [3] Experimentally it is very difficult to measure properties in these systems at sub-micron and nanoscales. Theoretically it is very difficult to determine the contributions from the films, interfaces, and substrates. As a result our understanding of deformation and fracture behavior in compliant substrate systems is limited. This motivated a study of buckle driven delamination of thin hard tungsten films on pure PMMA substrates. The films were sputter deposited to thicknesses of 100 nm, 200 nm, and 400 nm with a residual compressive stress of 1.7 GPa. An aluminum oxide interlayer was added on several samples to alter interfacial composition. Buckles formed spontaneously on the PMMA substrates following film deposition. On films without the aluminum oxide interlayer, an extensive network of small telephone cord buckles formed following deposition, interspersed with regions of larger telephone cord buckles. (Figure 1) On films with an aluminum oxide interlayer, telephone cord buckles formed creating a uniform widely spaced pattern. Through-substrate optical observations revealed matching buckle patterns along the film-substrate interface indicating that delamination occurred for large and small buckles with and without an interlayer. The coexistence of large and small buckles on the same substrate led to two distinct behaviors as shown in Figure 2 where normalized buckle heights are plotted against normalized film stress. The behaviors deviate significantly from

  7. Buckle Driven Delamination in Thin Hard Film Compliant Substrate Systems

    Directory of Open Access Journals (Sweden)

    Bahr D.F.

    2010-06-01

    Full Text Available Deformation and fracture of thin films on compliant substrates are key factors constraining the performance of emerging flexible substrate devices. [1-3] These systems often contain layers of thin polymer, ceramic and metallic films and stretchable interconnects where differing properties induce high normal and shear stresses. [4] As long as the films remain bonded to the substrates, they may deform far beyond their freestanding form. Once debonded, substrate constraint disappears leading to film failure. [3] Experimentally it is very difficult to measure properties in these systems at sub-micron and nanoscales. Theoretically it is very difficult to determine the contributions from the films, interfaces, and substrates. As a result our understanding of deformation and fracture behavior in compliant substrate systems is limited. This motivated a study of buckle driven delamination of thin hard tungsten films on pure PMMA substrates. The films were sputter deposited to thicknesses of 100 nm, 200 nm, and 400 nm with a residual compressive stress of 1.7 GPa. An aluminum oxide interlayer was added on several samples to alter interfacial composition. Buckles formed spontaneously on the PMMA substrates following film deposition. On films without the aluminum oxide interlayer, an extensive network of small telephone cord buckles formed following deposition, interspersed with regions of larger telephone cord buckles. (Figure 1 On films with an aluminum oxide interlayer, telephone cord buckles formed creating a uniform widely spaced pattern. Through-substrate optical observations revealed matching buckle patterns along the film-substrate interface indicating that delamination occurred for large and small buckles with and without an interlayer. The coexistence of large and small buckles on the same substrate led to two distinct behaviors as shown in Figure 2 where normalized buckle heights are plotted against normalized film stress. The behaviors deviate

  8. Optimization of solid substrate fermentation of wheat straw.

    Science.gov (United States)

    Abdullah, A L; Tengerdy, R P; Murphy, V G

    1985-01-01

    Optimal conditions for solid substrate fermentation of wheat straw with Chaetomium cellulolyticum in laboratory-scale stationary layer fermenters were developed. The best pretreatment for wheat straw was ammonia freeze explosion, followed by steam treatment, alkali treatment, and simple autoclaving. The optimal fermentation conditions were 80% (w/w) moisture content; incubation temperature of 37 degrees C; 2% (w/w) unwashed mycelial inoculum; aeration at 0.12 L/h/g; substrate thickness of 1 to 2 cm; and duration of three days. Technical parameters for this optimized fermentation were: degree of substance utilization, 27.2%; protein yield/substrate, 0.09 g; biomass yield/bioconverted substrate, 0.40 g; degree of bioconversion of total available sugars in the substrate, 60.5%; specific efficiency of bioconversion, 70.8%; and overall efficiency of biomass production from substrate, 42.7%. Mixed culturing of Candida utilis further increased biomass production by 20%. The best mode of fermentation was a semicontinuous fed-batch fermentation where one-half of the fermented material was removed at three-day intervals and replaced by fresh substrate. In this mode, protein production was 20% higher than in batch mode, protein productivity was maintained over 12 days, and sporulation was prevented.

  9. Electropolymerization of pyrrole on silanized polycrystalline titanium substrates

    Energy Technology Data Exchange (ETDEWEB)

    Mekhalif, Z. [Laboratory of Chemistry and Electrochemistry of Surfaces, University of Namur (FUNDP), Rue de Bruxelles, 61, B-5000 Namur (Belgium)], E-mail: zineb.mekhalif@fundp.ac.be; Cossement, D.; Hevesi, L.; Delhalle, J. [Laboratory of Chemistry and Electrochemistry of Surfaces, University of Namur (FUNDP), Rue de Bruxelles, 61, B-5000 Namur (Belgium)

    2008-04-30

    In this work is reported the silanization of titanium substrates and subsequent polymerization of pyrrole on the resulting substrates. First, titanium substrates were modified by n-hexyltrichlorosilane (HTCS) and 6-(1'-pyrrolyl)-n-hexyltrichlorosilane (PyHTCS). The corresponding self-assembled monolayers were characterized by X-ray photoelectron spectroscopy and contact angle measurements. They were found to be densely packed. Second, pyrrole was electrochemically polymerized on silanized titanium substrates. Chronoamperometry was used to study the growth of polypyrrole films. The polymer films were characterized by qualitative peel tests, cyclic voltametry and scanning electron spectroscopy. Polypyrrole grown from PyHTCS was found to adherent as compared to HTCS modified and bare substrates. Cyclic voltametry indicated that polymer films formed from PyHTCS have an oxidation peak potential located at higher values than HTCS-modified and bare substrates. Moreover, the films grown on the three types of substrates were found to be equally uniform. Finally, we improved the electrochemical properties of the polypyrrole films using a two-step process, electroreticulation of the PyHTCS monolayers followed by a pyrrole polymerization.

  10. SVM-based prediction of caspase substrate cleavage sites

    Directory of Open Access Journals (Sweden)

    Ranganathan Shoba

    2006-12-01

    Full Text Available Abstract Background Caspases belong to a class of cysteine proteases which function as critical effectors in apoptosis and inflammation by cleaving substrates immediately after unique sites. Prediction of such cleavage sites will complement structural and functional studies on substrates cleavage as well as discovery of new substrates. Recently, different computational methods have been developed to predict the cleavage sites of caspase substrates with varying degrees of success. As the support vector machines (SVM algorithm has been shown to be useful in several biological classification problems, we have implemented an SVM-based method to investigate its applicability to this domain. Results A set of unique caspase substrates cleavage sites were obtained from literature and used for evaluating the SVM method. Datasets containing (i the tetrapeptide cleavage sites, (ii the tetrapeptide cleavage sites, augmented by two adjacent residues, P1' and P2' amino acids and (iii the tetrapeptide cleavage sites with ten additional upstream and downstream flanking sequences (where available were tested. The SVM method achieved an accuracy ranging from 81.25% to 97.92% on independent test sets. The SVM method successfully predicted the cleavage of a novel caspase substrate and its mutants. Conclusion This study presents an SVM approach for predicting caspase substrate cleavage sites based on the cleavage sites and the downstream and upstream flanking sequences. The method shows an improvement over existing methods and may be useful for predicting hitherto undiscovered cleavage sites.

  11. Recent advances in designing substrate-competitive protein kinase inhibitors.

    Science.gov (United States)

    Han, Ki-Cheol; Kim, So Yeon; Yang, Eun Gyeong

    2012-01-01

    Protein kinases play central roles in cellular signaling pathways and their abnormal phosphorylation activity is inseparably linked with various human diseases. Therefore, modulation of kinase activity using potent inhibitors is an attractive strategy for the treatment of human disease. While most protein kinase inhibitors in clinical development are mainly targeted to the highly conserved ATP-binding sites and thus likely promiscuously inhibit multiple kinases including kinases unrelated to diseases, protein substrate-competitive inhibitors are more selective and expected to be promising therapeutic agents. Most substrate-competitive inhibitors mimic peptides derived from substrate proteins, or from inhibitory domains within kinases or inhibitor proteins. In addition, bisubstrate inhibitors are generated by conjugating substrate-competitive peptide inhibitors to ATP-competitive inhibitors to improve affinity and selectivity. Although structural information on protein kinases provides invaluable guidance in designing substrate-competitive inhibitors, other strategies including bioinformatics, computational modeling, and high-throughput screening are often employed for developing specific substrate-competitive kinase inhibitors. This review focuses on recent advances in the design and discovery of substrate-competitive inhibitors of protein kinases.

  12. Periphyton biomass on artificial substrates during the summer and winter

    Directory of Open Access Journals (Sweden)

    Altevir Signor

    2015-01-01

    Full Text Available This study evaluated the periphyton production on artificial substrates considering it as a source of low cost live food for fish. Blades of artificial substrates such as wood, black plastic, acrylic, fiberglass, ceramics and glass (all with 144cm2 blades, 24 for each substrate were submerged 20.0cm below the water column for 35 days in the winter and 42 days in the summer. The blades were randomly installed in 200m3 pond and evaluated for the biomass production at different phases during the summer and winter. Four blades of each substrate were collected weekly, and the periphytic community was carefully scraped with a spatula and fixed in 4% formaldehyde. The periphytic biomass productivity was evaluated by artificial substrate area and per day. The results evidenced the characteristic periodicity in periphyton biomass production and a significant variability in the collect period and season in the different artificial substrates used. Ceramic and wood showed the best results in the summer while wood showed the best results in the winter. The priphyton biomass productions differ among periods, substrates and seasons. Wood and ceramics could be indicated for periphyton biomass production in either winter or summer.

  13. Substrate stiffness regulates extracellular matrix deposition by alveolar epithelial cells

    Science.gov (United States)

    Eisenberg, Jessica L; Safi, Asmahan; Wei, Xiaoding; Espinosa, Horacio D; Budinger, GR Scott; Takawira, Desire; Hopkinson, Susan B; Jones, Jonathan CR

    2012-01-01

    Aim The aim of the study was to address whether a stiff substrate, a model for pulmonary fibrosis, is responsible for inducing changes in the phenotype of alveolar epithelial cells (AEC) in the lung, including their deposition and organization of extracellular matrix (ECM) proteins. Methods Freshly isolated lung AEC from male Sprague Dawley rats were seeded onto polyacrylamide gel substrates of varying stiffness and analyzed for expression and organization of adhesion, cytoskeletal, differentiation, and ECM components by Western immunoblotting and confocal immunofluorescence microscopy. Results We observed that substrate stiffness influences cell morphology and the organization of focal adhesions and the actin cytoskeleton. Surprisingly, however, we found that substrate stiffness has no influence on the differentiation of type II into type I AEC, nor does increased substrate stiffness lead to an epithelial–mesenchymal transition. In contrast, our data indicate that substrate stiffness regulates the expression of the α3 laminin subunit by AEC and the organization of both fibronectin and laminin in their ECM. Conclusions An increase in substrate stiffness leads to enhanced laminin and fibronectin assembly into fibrils, which likely contributes to the disease phenotype in the fibrotic lung. PMID:23204878

  14. Carbon Nanotube Microarrays Grown on Nanoflake Substrates

    Science.gov (United States)

    Schmidt, Howard K.; Hauge, Robert H.; Pint, Cary; Pheasant, Sean

    2013-01-01

    This innovation consists of a new composition of matter where single-walled carbon nanotubes (SWNTs) are grown in aligned arrays from nanostructured flakes that are coated in Fe catalyst. This method of growth of aligned SWNTs, which can yield well over 400 percent SWNT mass per unit substrate mass, exceeds current yields for entangled SWNT growth. In addition, processing can be performed with minimal wet etching treatments, leaving aligned SWNTs with superior properties over those that exist in entangled mats. The alignment of the nanotubes is similar to that achieved in vertically aligned nanotubes, which are called "carpets. " Because these flakes are grown in a state where they are airborne in a reactor, these flakes, after growing SWNTs, are termed "flying carpets. " These flakes are created in a roll-to-roll evaporator system, where three subsequent evaporations are performed on a 100-ft (approx. =30-m) roll of Mylar. The first layer is composed of a water-soluble "release layer, " which can be a material such as NaCl. After depositing NaCl, the second layer involves 40 nm of supporting layer material . either Al2O3 or MgO. The thickness of the layer can be tuned to synthesize flakes that are larger or smaller than those obtained with a 40-nm deposition. Finally, the third layer consists of a thin Fe catalyst layer with a thickness of 0.5 nm. The thickness of this layer ultimately determines the diameter of SWNT growth, and a layer that is too thick will result in the growth of multiwalled carbon nanotubes instead of single-wall nanotubes. However, between a thickness of 0.5 nm to 1 nm, single-walled carbon nanotubes are known to be the primary constituent. After this three-layer deposition process, the Mylar is rolled through a bath of water, which allows catalyst-coated flakes to detach from the Mylar. The flakes are then collected and dried. The method described here for making such flakes is analogous to that which is used to make birefringent ink that is

  15. Method and apparatus for laser scribing glass sheet substrate coatings

    Energy Technology Data Exchange (ETDEWEB)

    Borgeson, Frank A.; Hanak, Joseph J.; Harju, Ricky S.; Helman, Norman L.; Hecht, Kenneth R.

    2003-05-06

    A method and apparatus (42) for laser scribing coatings on glass sheet substrates by conveying the substrate adjacent a laser source (83) that provides a pulsed laser beam (84) with a wavelength at a near-infrared fundamental frequency and having a frequency in the range of 50 to 100 kilohertz and a pulse duration in the range of 8 to 70 nanoseconds, and by reflecting the beam by an XYZ galvanometer controlled mirror system (90) toward an uncoated surface of the substrate for passage therethrough to the coating on the other surface to provide overlapping ablations through the coating and scribing at a speed of at least 1000 millimeters per second.

  16. Method and apparatus for laser scribing glass sheet substrate coatings

    Energy Technology Data Exchange (ETDEWEB)

    Borgeson, Frank A.; Hanak, Joseph J.; Harju, Ricky S.; Harju, Karen M.; Helman, Norman L.; Hecht, Kenneth R.

    2005-07-19

    A method and apparatus (42) for laser scribing coatings on glass sheet substrates by conveying the substrate adjacent a laser source (83) that provides a pulsed laser beam (84) with a wavelength at a near-infrared fundamental frequency and having a frequency in the range of 50 to 100 kilohertz and a pulse duration in the range of 8 to 70 nanoseconds, and by reflecting the beam by an XYZ galvanometer controlled mirror system (90) toward an uncoated surface of the substrate for passage therethrough to the coating on the other surface to provide overlapping ablations through the coating and scribing at a speed of at least 1000 millimeters per second.

  17. A new ultrasensitive bioluminogenic enzyme substrate for beta-galactosidase.

    Science.gov (United States)

    Geiger, R; Schneider, E; Wallenfels, K; Miska, W

    1992-12-01

    A derivative of D-luciferin, D-luciferin-O-beta-galactoside, was synthesized and used as highly sensitive substrate for beta-galactosidase. The substrate was physicochemically characterized. Enzymatic cleavage of the new compound by beta-galactosidase was demonstrated and kinetic constants Km, Vmax, kcat and kcat/Km have been determined. The compound has been proved to be a highly sensitive substrate for beta-galactosidase, permitting a limit of detection of 3.7 x 10(-19) mol of enzyme per assay.

  18. Investigation of (111 wafers and comparison with (100 substrates

    Directory of Open Access Journals (Sweden)

    A Bahari

    2012-06-01

    Full Text Available  In the last decade, Si(100 has been used as a suitable substrate in field effect transistors. Some issues such as leakage current and tunneling current through the ultrathin films have been increased with shrinking the electronic devices – particularly, field effect transistors – to nanoscale, which is threatening more use of Si(100. We have thus demonstrated a series of experiments to grow ultrathin films on both Si(100 and Si(111 substrates and studied their nanostructural properties to see the possibility of replacing Si(100 with Si(111. The obtained results indicate that Si(111 substrate with silicon nitride film on top is desirable.

  19. Substrate-adsorbate coupling in CO-adsorbed copper

    CERN Document Server

    Lewis, S P; Lewis, Steven P.; Rappe, Andrew M.

    1996-01-01

    The vibrational properties of carbon monoxide adsorbed to the copper (100) surface are explored within density functional theory. Atoms of the substrate and adsorbate are treated on an equal footing in order to examine the effect of substrate--adsorbate coupling. This coupling is found to have a significant effect on the vibrational modes, particularly the in-plane frustrated translation, which mixes strongly with substrate phonons and broadens into a resonance. The predicted lifetime due to this harmonic decay mechanism is in excellent quantitative agreement with experiment.

  20. Microgravimetric Studies of Selenium Electrodeposition Onto Different Substrates

    Directory of Open Access Journals (Sweden)

    Kowalik R.

    2014-10-01

    Full Text Available The mechanism of selenium electrodeposition from sulfuric acid solution on different substrates was studied with the electrochemical techniques. The cyclic voltammetry was combined with the quartz crystal microbalance technique to analyze selenium deposition process. The electrochemical reduction of selenous acid on gold, silver and copper electrodes was investigated. It was found that reduction of selenous acid is a very complex process and it strongly depends from the applied substrate. The voltammetric measurements indicate the range of potentials in which the process of reduction of selenous acids on the applied substrate is possible. Additionally, the microgravimetric data confirm the deposition of selenium and they reveal the mechanism of the deposition process.

  1. Substrate-enhanced superconductivity in Li-decorated graphene

    KAUST Repository

    Kaloni, Thaneshwor P.

    2013-11-01

    We investigate the role of the substrate for the strength of the electron-phonon coupling in Li-decorated graphene. We find that the interaction with a h-BN substrate leads to a significant enhancement from to , which corresponds to a 25% increase of the transition temperature from to . The superconducting gaps amount to 1.56 meV (suspended) and 1.98 meV (supported). These findings open up a new route to enhanced superconducting transition temperatures in graphene-based materials by substrate engineering. © 2013 EPLA.

  2. Lattice matched semiconductor growth on crystalline metallic substrates

    Science.gov (United States)

    Norman, Andrew G; Ptak, Aaron J; McMahon, William E

    2013-11-05

    Methods of fabricating a semiconductor layer or device and said devices are disclosed. The methods include but are not limited to providing a metal or metal alloy substrate having a crystalline surface with a known lattice parameter (a). The methods further include growing a crystalline semiconductor alloy layer on the crystalline substrate surface by coincident site lattice matched epitaxy. The semiconductor layer may be grown without any buffer layer between the alloy and the crystalline surface of the substrate. The semiconductor alloy may be prepared to have a lattice parameter (a') that is related to the lattice parameter (a). The semiconductor alloy may further be prepared to have a selected band gap.

  3. Effects of Different Substrates on Lignocellulosic Enzyme Expression, Enzyme Activity, Substrate Utilization and Biological Efficiency of Pleurotus Eryngii

    Directory of Open Access Journals (Sweden)

    Chunliang Xie

    2016-09-01

    Full Text Available Background/Aims: Pleurotus eryngii is one of the most valued and delicious mushrooms which are commercially cultivated on various agro-wastes. How different substrates affect lignocellulosic biomass degradation, lignocellulosic enzyme production and biological efficiency in Pleurotus eryngii was unclear. Methods and Results: In this report, Pleurotus eryngii was cultivated in substrates including ramie stalks, kenaf stalks, cottonseed hulls and bulrush stalks. The results showed that ramie stalks and kenaf stalks were found to best suitable to cultivate Pleurotus eryngii with the biological efficiency achieved at 55% and 57%, respectively. In order to establish correlations between different substrates and lignocellulosic enzymes expression, the extracellular proteins from four substrates were profiled with high throughput TMT-based quantitative proteomic approach. 241 non-redundant proteins were identified and 74 high confidence lignocellulosic enzymes were quantified. Most of the cellulases, hemicellulases and lignin depolymerization enzymes were highly up-regulated when ramie stalks and kenaf stalks were used as carbon sources. The enzyme activities results suggested cellulases, hemicellulases and lignin depolymerization enzymes were significantly induced by ramie stalks and kenaf stalks. Conclusion: The lignocelluloses degradation, most of the lignocellulosic enzymes expressions and activities of Pleurotus eryngii had positive correlation with the biological efficiency, which depend on the nature of lignocellulosic substrates. In addition, the lignocellulosic enzymes expression profiles during Pleurotus eryngii growth in different substrates were obtained. The present study suggested that most of the lignocellulosic enzymes expressions and activities can be used as tools for selecting better performing substrates for commercial mushroom cultivation.

  4. Gallium nitride epitaxy on silicon: Importance of substrate preparation

    Energy Technology Data Exchange (ETDEWEB)

    Martin, G.A.; Sverdlov, B.N.; Botchkarev, A.; Morkoc, H.; Thompson, W.H.; Nayfeh, M.H. [Univ. of Illinois, Urbana, IL (United States); Smith, D.J.; Tsen, S.C.Y. [Arizona State Univ., Tempe, AZ (United States)

    1996-11-01

    Hexagonal GaN films grown on non-isomorphic substrates are usually characterized by numerous threading defects which are essentially boundaries between wurtzite GaN domains where the stacking sequences do not align. One origin of these defects is irregularities on the substrate surface such as surface steps. Using Si <111> substrates and a substrate preparation procedure that makes wide atomically flat terraces, the authors demonstrate that reduction of these irregularities greatly improves the crystalline and luminescent quality of GaN films grown by plasma-enhanced molecular beam epitaxy. X-ray rocking curve width decreases from over 1 degree to less than 20 minutes, while PL halfwidth decreases from over 15 meV to less than 10 meV.

  5. Plasma enhanced diamond deposition on steel and Si substrates

    Institute of Scientific and Technical Information of China (English)

    Y.S. Li; Y. Tang; W. Chen; Q. Yang; C. Xiao; A. Hirose

    2009-01-01

    Diamond growth on Fe-Cr-Al-Si steel and Si substrates was comparatively investigated in microwave plasma enhanced chemical vapor deposition (MPCVD) reactor with different deposition parameters. Adherent nanocrystalline diamond films were directly deposited on this steel substrate under a typical deposition condition, whereas microcrystalline diamond films were produced on Si wafer. With increasing CH4 concentration, reaction pressure, or the total gas flow rate, the quality of nanocrystalline diamond films formed on Fe-Cr-Al-Si substrates is gradually deteriorated in terms of density and adhesion. This impaired diamond quality on steels is primarily associated with a combined effect by the substrate composition and the specific process conditions that favor excessive nucleation of diamond.

  6. Structure and energetics of helium films on alkali substrates

    Science.gov (United States)

    Boninsegni, Massimo; Szybisz, Leszek

    2004-07-01

    Low-temperature adsorption of He4 films on Alkali metal substrates is investigated theoretically by means of ground-state quantum Monte Carlo simulations. The most accurate potentials currently available are utilized to model the interaction of He4 atoms with the substrate. Continuous growth of film thickness as a function of chemical potential is observed on Li, Na, and K substrates. A superfluid monolayer forms on a Li substrate; on Na and K, thermodynamically stable films are a few layers thick. The uncertainties of the calculation and in the potentials, preclude a definitive conclusion on the existence of a stable He4 film on Rb. A comparison of the results of this calculation with those obtained using the Orsay-Trento density functional shows broad quantitative agreement.

  7. ADHESION STRENGTH OF COATING SUBSTRATE AND SURFACE MORPHOLOGY OF PRETREATMENT

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Premature failure of coated tool often results from a poor adhesion of coating-substrate and shortens the lifetime of the tool.The results of increasing the adhesion strength of thin film coatings on cutting tool inserts by pretreating the inserts with sandblasting technique to obtain a desirable surface morphology of the inserts are presented.A geometric model representing the ideal surface morphology is established to enhance the nucleation density and adhesion strength of coating-substrate.Thin film coating experiment is conducted on the substrates of four different sample groups.Indentation and wear tests are performed on coated inserts to evaluate the effect of sandblasting on the adhesion strength of the coatings.A theoretical analysis is provided on the formation and growth of atom clusters in terms of the contact angle and the thermodynamic barrier of a substrate to predict thin film nucleation.

  8. Bending characteristic of a cantilevered magnetostrictive film-substrate system

    Institute of Scientific and Technical Information of China (English)

    B.; Narsu

    2007-01-01

    The bending problem of a film-substrate cantilever with arbitrary film-to-substrate thickness ratio is solved exactly by employing the force equilibrium equation, and then the optimization and application of the bending characteristic of the magne-tostrictive cantilever is discussed. Furthermore, the influence of geometrical and physical parameters of the two cantilever components on the maximum free-end deflection of the cantilever is addressed. The results indicate that as the substrate thickness is kept constant, the greater film-to-substrate stiffness ratio will induce a larger deflection, while for the case of fixed total cantilever thickness, the optimal cantilever deflection is independent of the physical parameters of the materials such as Young’s modulus and Poisson’s ratio.

  9. Bending characteristic of a cantilevered magnetostrictive film-substrate system

    Institute of Scientific and Technical Information of China (English)

    B. Narsu; YUN GuoHong

    2007-01-01

    The bending problem of a film-substrate cantilever with arbitrary film-to-substrate thickness ratio is solved exactly by employing the force equilibrium equation, and then the optimization and application of the bending characteristic of the magnetostrictive cantilever is discussed. Furthermore, the influence of geometrical and physical parameters of the two cantilever components on the maximum free-end deflection of the cantilever is addressed. The results indicate that as the substrate thickness is kept constant, the greater film-to-substrate stiffness ratio will induce a larger deflection, while for the case of fixed total cantilever thickness, the optimal cantilever deflection is independent of the physical parameters of the materials such as Young's modulus and Poisson's ratio.

  10. Modeling of the substrate influence on multielement THz detector operation

    CERN Document Server

    Sakhno, M; Sizov, F

    2015-01-01

    The development of THz multielement uncooled imagers based on focal plane arrays (FPAs) requires an optimization of the system parameters to achieve a homogeneous sensitivity of the array elements. Results of numerical simulation of the eight-element linear array of planar antennas with detecting elements, on a substrate of finite dimensions are presented. We establish how the substrate thickness h and the relative permittivity epsilon influence antenna pattern and antenna-detector matching for each element. We show that the antenna pattern depends on the detector position more than the antenna-detector impedance matching. The gain of array elements, the antenna-detector matching, and the homogeneity of the detector sensitivity can be simultaneously optimized by the proper choice of the substrate thickness h and the relative permittivity epsilon. We show that multielement systems with large substrate thickness and high relative permittivity are not suitable for the imaging system implementation. To achieve un...

  11. MBE growth of GaP on a Si substrate

    Energy Technology Data Exchange (ETDEWEB)

    Sobolev, M. S., E-mail: sobolev@gmail.com; Lazarenko, A. A.; Nikitina, E. V.; Pirogov, E. V.; Gudovskikh, A. S.; Egorov, A. Yu. [Russian Academy of Sciences, St. Petersburg Academic University, Nanotechnology Research and Education Centre (Russian Federation)

    2015-04-15

    It is shown that single-crystal GaP buffer layers can be formed on a Si substrate by molecular-beam epitaxy, with the “migration-enhanced epitaxy” procedure applied in the stage in which the nucleating layer is formed. When a GaP layer is produced on a p-type silicon substrate, a p-n junction is created in a natural way between the p-Si substrate and the surface n-Si layer produced by the diffusion of phosphorus into the substrate during the course of the epitaxial growth of GaP. This p-n junction can be used as the first junction of a silicon-based multijunction photovoltaic converter.

  12. Microwave flexible transistors on cellulose nanofibrillated fiber substrates

    Science.gov (United States)

    Seo, Jung-Hun; Chang, Tzu-Hsuan; Lee, Jaeseong; Sabo, Ronald; Zhou, Weidong; Cai, Zhiyong; Gong, Shaoqin; Ma, Zhenqiang

    2015-06-01

    In this paper, we demonstrate microwave flexible thin-film transistors (TFTs) on biodegradable substrates towards potential green portable devices. The combination of cellulose nanofibrillated fiber (CNF) substrate, which is a biobased and biodegradable platform, with transferrable single crystalline Si nanomembrane (Si NM), enables the realization of truly biodegradable, flexible, and high performance devices. Double-gate flexible Si NM TFTs built on a CNF substrate have shown an electron mobility of 160 cm2/V.s and fT and fmax of 4.9 GHz and 10.6 GHz, respectively. This demonstration proves the microwave frequency capability and, considering today's wide spread use of wireless devices, thus indicates the much wider utility of CNF substrates than that has been demonstrated before. The demonstration may also pave the way toward portable green devices that would generate less persistent waste and save more valuable resources.

  13. Substrate vibrations during courtship in three Drosophila species.

    Directory of Open Access Journals (Sweden)

    Valerio Mazzoni

    Full Text Available While a plethora of studies have focused on the role of visual, chemical and near-field airborne signals in courtship of Drosophila fruit flies, the existence of substrate-borne vibrational signals has been almost completely overlooked. Here we describe substrate vibrations generated during courtship in three species of the D. melanogaster group, from the allegedly mute species D. suzukii, its sister species D. biarmipes, and from D. melanogaster. In all species, we recorded several types of substrate vibrations which were generated by locomotion, abdominal vibrations and most likely through the activity of thoracic wing muscles. In D. melanogaster and D. suzukii, all substrate vibrations described in intact males were also recorded in males with amputated wings. Evidence suggests that vibrational signalling may be widespread among Drosophila species, and fruit flies may provide an ideal model to study various aspects of this widespread form of animal communication.

  14. Two-substrate vertical deposition for stable colloidal crystal chips

    Institute of Scientific and Technical Information of China (English)

    CHEN Xin; SUN Zhiqiang; CHEN Zhimin; ZHANG Kai; YANG Bai

    2005-01-01

    By combining vertical deposition with micromolding in capillaries method, we have demonstrated the two-substrate vertical deposition, an alternative and versatile procedure for fabricating high-quality stable colloidal crystal chips. Apparent bright colors, special UV-vis spectra, scanning electron microscopy (SEM) and atomic force microscopy (AFM) images all prove that high-quality colloidal crystal structures are formed in between the two substrates. During the two-substrate vertical deposition for colloidal crystal chips, capillary force and evaporation of the medium are critical to the formation of the colloidal crystals; while the confinement in between two close substrates makes the resulting colloidal crystal chips more stable. Due to the excellent stability, these colloidal crystal chips can be used to construct some composite optical devices via a simpler and more flexible process. Meanwhile, they can also be further used as the templates for ordered multiporous materials.

  15. In situ synthesis of nanoparticles on substrates by inkjet printing

    KAUST Repository

    Abulikemu, Mutalifu

    2014-12-23

    Nanoparticles may be formed on a substrate by mixing precursor solutions deposited by an inkjet printer. A first solution is deposited on a substrate from a first inkjet print cartridge. Then, a second solution is deposited on the substrate from a second inkjet print cartridge. The solutions may be printed in an array of droplets on the substrate. Nanoparticles form when droplets of the first solution overlap with droplets of the second solution. In one example, the nanoparticles may be gold nanoparticles formed from mixing a first solution of 1,2-dichlorobenzene (DCB) and oleylamine and a second solution of gold chloride trihydrite and dimethyl sulfoxide (DMSO). The nanoparticles may be incorporated into optoelectronic devices.

  16. Silicon based substrate with environmental/ thermal barrier layer

    Science.gov (United States)

    Eaton, Jr., Harry Edwin (Inventor); Allen, William Patrick (Inventor); Jacobson, Nathan S. (Inventor); Bansal, Nanottam P. (Inventor); Opila, Elizabeth J. (Inventor); Smialek, James L. (Inventor); Lee, Kang N. (Inventor); Spitsberg, Irene T. (Inventor); Wang, Hongyu (Inventor); Meschter, Peter Joel (Inventor)

    2002-01-01

    A barrier layer for a silicon containing substrate which inhibits the formation of gaseous species of silicon when exposed to a high temperature aqueous environment comprises a barium-strontium alumino silicate.

  17. Silicon based substrate with calcium aluminosilicate/thermal barrier layer

    Science.gov (United States)

    Eaton, Jr., Harry Edwin (Inventor); Allen, William Patrick (Inventor); Miller, Robert Alden (Inventor); Jacobson, Nathan S. (Inventor); Smialek, James L. (Inventor); Opila, Elizabeth J. (Inventor); Lee, Kang N. (Inventor); Nagaraj, Bangalore A. (Inventor); Wang, Hongyu (Inventor); Meschter, Peter Joel (Inventor)

    2001-01-01

    A barrier layer for a silicon containing substrate which inhibits the formation of gaseous species of silicon when exposed to a high temperature aqueous environment comprises a calcium alumino silicate.

  18. Silicon—a new substrate for GaN growth

    Indian Academy of Sciences (India)

    S Pal; C Jacob

    2004-12-01

    Generally, GaN-based devices are grown on silicon carbide or sapphire substrates. But these substrates are costly and insulating in nature and also are not available in large diameter. Silicon can meet the requirements for a low cost and conducting substrate and will enable integration of optoelectronic or high power electronic devices with Si based electronics. But the main problem that hinders the rapid development of GaN devices based on silicon is the thermal mismatch of GaN and Si, which generates cracks. In 1998, the first MBE grown GaN based LED on Si was made and now the quality of material grown on silicon is comparable to that on sapphire substrate. It is only a question of time before Si based GaN devices appear on the market. This article is a review of the latest developments in GaN based devices on silicon.

  19. Structural characteristics of titanium coating on copper substrates

    Indian Academy of Sciences (India)

    Arup Dasgupta; Akash Singh; Pradyumna Kumar Parida; R Ramaseshan; P Kuppusami; S Saroja; M Vijayalakshmi

    2011-06-01

    The growth characteristics of titanium films deposited on glass, silicon (100) and oxygen free high purity copper substrate using magnetron sputtering have been investigated using X-ray diffraction, electron microscopy and scratch indentation techniques. The study of interface between the titanium film and the substrate was carried out to determine coating thickness, as well as intermixing of the elements at the interface. Studies revealed that the interface is free from voids and intermixing of the film and the substrate. Microstructural and diffraction analysis showed that the Ti coating was polycrystalline and exhibited columnar growth. The Ti crystallite size varied between 24 and 58 nmdepending on the substrate. The thickness of the films were typically about 4 m. Scratch test indicated that the films are adherent and the first critical load to failure was observed to be 4.5 N ± 2 N.

  20. Integrated Broadband Bowtie Antenna on Transparent Silica Substrate

    CERN Document Server

    Zhang, Xingyu; Wang, Shiyi; Subbaraman, Harish; Pan, Zeyu; Zhan, Qiwen; Chen, Ray T

    2016-01-01

    The bowtie antenna is a topic of growing interest in recent years. In this paper, we design, fabricate, and characterize a modified gold bowtie antenna integrated on a transparent silica substrate. The bowtie antenna is designed with broad RF bandwidth to cover the X-band in the electromagnetic spectrum. We numerically investigate the antenna characteristics, specifically its resonant frequency and enhancement factor. Our designed bowtie antenna provides a strong broadband electric field enhancement in its feed gap. Taking advantage of the low-k silica substrate, high enhancement factor can be achieved without the unwanted reflection and scattering from the backside silicon handle which is the issue of using an SOI substrate. We simulate the dependence of resonance frequency on bowtie geometry, and verify the simulation results through experimental investigation, by fabricating different sets of bowtie antennas on silica substrates and then measuring their resonance frequencies. In addition, the far-field rad...

  1. Fibrinogen patterns and activity on substrates with tailored hydroxy density.

    Science.gov (United States)

    Rodríguez Hernández, José Carlos; Rico, Patricia; Moratal, David; Monleón Pradas, Manuel; Salmerón-Sánchez, Manuel

    2009-08-11

    The influence of the surface fraction of OH groups on fibrinogen (FG) adsorption is investigated in copolymers of ethyl acrylate and hydroxy ethylacrylate. The amount of adsorbed FG, quantified by western-blotting combined with image analysis of the corresponding bands, decreases as the hydrophilicity of the substrate increases. The influence of substrate wettability on FG conformation and distribution is observed by atomic force microscopy (AFM). The most hydrophobic substrate promotes FG fibrillogenesis, which leads to a fibrin-like appearance in the absence of any thrombin. The degree of FG interconnection was quantified by calculating the fractal dimension of the adsorbed protein from image analysis of the AFM results. The biological activity of the adsorbed FG is correlated to cell adhesion on FG-coated substrates.

  2. Silicon based substrate with environmental/thermal barrier layer

    Science.gov (United States)

    Eaton, Jr., Harry Edwin (Inventor); Allen, William Patrick (Inventor); Jacobson, Nathan S. (Inventor); Bansal, Narottam P. (Inventor); Opila, Elizabeth J. (Inventor); Smialek, James L. (Inventor); Lee, Kang N. (Inventor); Spitsberg, Irene T. (Inventor); Wang, Hongyu (Inventor); Meschter, Peter Joel (Inventor)

    2002-01-01

    A barrier layer for a silicon containing substrate which inhibits the formation of gaseous species of silicon when exposed to a high temperature aqueous environment comprises a barium-strontium alumino silicate.

  3. Characterization of Hydroxyapatite Film on Titanium Substrate by Sputtering Technique

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Radiofrequent magnetron sputtering technique was used to produce calcium phosphate coated on the titanium substrates, and the sputtered coating films were crystallized in an autoclave at 110 ℃ using a low temperature hydrothermal technique. The crystallization of as- sputtered coating film on the titanium substrates were amorphous calcium phosphate film. However, after the hydrothermal technique, calcium phosphate crystals grew and these were columnar crystal. The Ca/ P ratio of sputtered coating films in 1.6 to 2.0.

  4. Gecko Adhesion on Wet and Dry Patterned Substrates

    OpenAIRE

    Alyssa Y Stark; Palecek, Amanda M.; Argenbright, Clayton W.; Craig Bernard; Brennan, Anthony B; Niewiarowski, Peter H.; Ali Dhinojwala

    2015-01-01

    Perhaps one of the most astounding characteristics of the gecko adhesive system is its versatility. Geckos can locomote across complex substrates in a variety of conditions with apparent ease. In contrast, many of our synthetic pressure sensitive adhesives fail on substrates that are dirty, wet or rough. Although many studies have investigated the effect of environmental challenges on performance, the interaction of multiple, potentially compromising variables is studied less often. Here we f...

  5. Mode structure of planar optical antennas on dielectric substrates.

    Science.gov (United States)

    Word, Robert C; Könenkamp, Rolf

    2016-08-08

    We report a numerical study, supported by photoemission electron microscopy (PEEM), of sub-micron planar optical antennas on transparent substrate. We find these antennas generate intricate near-field spatial field distributions with odd and even numbers of nodes. We show that the field distributions are primarily superpositions of planar surface plasmon polariton modes confined to the metal/substrate interface. The mode structure provides opportunities for coherent switching and optical control in sub-micron volumes.

  6. Progress Towards III-V Photovoltaics on Flexible Substrates

    Science.gov (United States)

    McNatt, Jeremiah S.; Pal, AnnaMaria T.; Clark, Eric B.; Sayir, Ali; Raffaelle, Ryne P.; Bailey, Christopher G.; Hubbard, Seth M.; Maurer, William F.; Fritzemeier, Les

    2008-01-01

    Presented here is the recent progress of the NASA Glenn Research Center OMVPE group's efforts in the development of high efficiency thin-film polycrystalline III-V photovoltaics on optimum substrates. By using bulk polycrystalline germanium (Ge) films, devices of high efficiency and low mass will be developed and incorporated onto low-cost flexible substrates. Our progress towards the integration of high efficiency polycrystalline III-V devices and recrystallized Ge films on thin metal foils is discussed.

  7. Strong Substrate Dependence of Joule Heating in Graphene

    OpenAIRE

    Li, X.; Kong, B. D.; Zavada, J. M.; Kim, K W

    2011-01-01

    The Joule heating effect on graphene electronic properties is investigated by using full-band Monte Carlo electron dynamics and three-dimensional heat transfer simulations self-consistently. A number of technologically important substrate materials are examined: SiO2, SiC, hexagonal BN, and diamond. The results illustrate that the choice of substrate has a major impact via the heat conduction and surface polar phonon scattering. Particularly, it is found that the poor thermal conductivity of ...

  8. Ultrasound-Enhanced Biogas Production from Different Substrates

    DEFF Research Database (Denmark)

    González-Fernández, Cristina; Timmers, Rudolphus Antonius; Ruiz, Begona

    2015-01-01

    Among the biofuel production processes using different substrates, the biogas generation process is one of the simplest. Compared with bioethanol or biodiesel production processes, anaerobic digestion is a process where all the organic matter (carbohydrates, lipids and proteins) can be biologically...... production. The present chapter is dedicated to providing a review of ultrasound pretreatment applied to different substrates (lignocelullosic materials, manures, sludge and microalgae). The advantages and constraints, that ultrasound pretreatment exhibit towards biogas production, are discussed and compared...

  9. Substrate utilization and VSS relations in activated sludge processes

    Energy Technology Data Exchange (ETDEWEB)

    Droste, R.L.; Fernandes, L.; Sun, X. [Ottawa Univ., ON (Canada). Dept. of Civil Engineering

    1993-12-31

    A new empirical substrate removal model for activated sludge in continuous flow stirred tank reactor (CFSTR) and sequencing batch reactor (SBR) was developed in this study. This model includes an exponential function of volatile suspended solids to express the active biomass which is actually involved in substrate utilization. Results indicate that the proposed exponential models predict more accurately effluent COD in CFSTR and SBR systems than the first or zero order models. (author). 7 refs., 1 fig., 4 tabs.

  10. Integrated silicon and silicon nitride photonic circuits on flexible substrates.

    Science.gov (United States)

    Chen, Yu; Li, Mo

    2014-06-15

    Flexible integrated photonic devices based on crystalline materials on plastic substrates have a promising potential in many unconventional applications. In this Letter, we demonstrate a fully integrated photonic system including ring resonators and grating couplers, based on both crystalline silicon and silicon nitride, on flexible plastic substrate by using the stamping-transfer method. A high yield has been achieved by a simple, yet reliable transfer method without significant performance degradation.

  11. Agronomic assessment of spent substrates for mushroom cultivation

    Directory of Open Access Journals (Sweden)

    Picornell-Buendía, R.

    2016-01-01

    Full Text Available Description of the subject. In this work the agronomic viability of substrates based on spent Agaricus bisporus Imbach (Lange substrates (SAS and spent Pleurotus ostreatus (Jacq. P. Kumm. substrates (SPS is studied. Objectives. The aim of this work is the qualitative agronomic evaluation of SPS and SAS and the mixture of thereof in different proportions, such as lignocellulosic sources in new growing cycles of P. ostreatus. Method. In addition to the commercial substrate used as a control reference, six different treatments are considered. In this experiment, SPS and SAS were mixed in different amounts. SAS was subjected to a heat treatment in a growing room ("cook out" and then to a maturation treatment which consisted of a controlled recomposting process in cameras. SPS was subjected to a pasteurizing heat treatment (60 °C – 65 °C, 8 h and a progressive temperature decrease for at least 15 h to a "seeding" temperature (25 °C. Results. SPS (3,600 g + SAS (2,400 g and SPS (3,000 g + SAS (3,000 g were prepared substrates that achieved acceptable crude protein content in their fruiting bodies. Additionally, we obtained higher ash content, lightness, yellow-blue (y-b and red-green (r-g chromaticity, breaking strength (Bs, and compression energy (CE in these mushrooms. These values were higher than the mean values, and even higher than the commercial substrate. Conclusions. Increased SAS participation in the mixture of the processed substrate (and the consequent reduction of SPS participation resulted in mushrooms that require higher Bs, and CE. These formulation-based composts degraded by the growth of P. ostreatus, could be a low-cost substrate with selective and balanced nutrients for growth and development of oyster mushrooms.

  12. Exploring New RF Circuit Structures with Embedded Patterned Substrate Layers

    Science.gov (United States)

    2013-06-12

    spaced microstrip lines are common in T/R module packages and other high density circuit packages. The work involved creating a method to reduce the...Jan-2013 Approved for Public Release; Distribution Unlimited Final Report: Exploring New RF Circuit Structures with Embedded Patterned Substrate...Report: Exploring New RF Circuit Structures with Embedded Patterned Substrate Layers Report Title This report presents the findings made under the ARO

  13. Evaluation of fly ash as a component of potting substrates

    Energy Technology Data Exchange (ETDEWEB)

    Menzies, N.W.; Aitken, R.L. [University of Queensland, St. Lucia, Qld. (Australia). Dept. of Agriculture

    1996-11-01

    A series of laboratory and glasshouse experiments were undertaken to assess the potential for incorporating fly ash in soilless potting substrates. Since fly ash is available at low cost and can be successfully substituted for a considerable portion of the expensive peat component in the peat:sand mix, its use at low application rates in potting substrates may be desirable from an economic viewpoint.

  14. Experimental observations on fungal diagenesis of carbonate substrates

    Science.gov (United States)

    Kolo, Kamal; Keppens, Eddy; PréAt, Alain; Claeys, Philippe

    2007-03-01

    Carbonate substrates (dolomites and limestones) are susceptible to fungal attack that results in significant microbial diagenesis of these substrates. In a 15-day experimental study, fungi growing in Petri dishes from airborne spores attacked petrographic thin sections and chips prepared from the dolomites of Terwagne Formation (Viséan, Bocahut quarry at Avesnes-sur-Helpe, northern France) and limestones of the Morrone di Pacentro Formation (Lower Cretaceous, Italy). The analyses of the fungal material (samples of mycelia), thin sections and chips under optical microscopy, scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), Raman spectroscopy and stable isotopes (C and O) revealed an extensive fungally induced diagenesis. The results indicate strong diagenesis and biomineral neomorphism: neo-dolomite, glushinskite, weddellite, whewellite and possibly struvite, as well as intense substrate "de-micritization" and "micritization" with oxalates, grain bridging and cementation, open space filling, formation of intergranular and intragranular porosity, and permeability enhancement. Advanced stages of diagenesis were characterized by dissolution and replacement of original minerals by new substrates produced by fungal biomineralization. The formation of new substrates on the original attacked surfaces produced microscale stratification. Stable isotope analysis of fungal biomineralized material and of attacked and unattacked chip surfaces revealed marked differences in their isotopic signatures. The C and O isotopes of biomineralized material within the fungal mass were fractionated differently as compared to the signature measured in the original and unattacked surfaces. In sedimentary cycles, such microbially modified isotopic signature of carbonate substrates may be used to define microbial events, and consequently whether certain types of diagenesis were produced by microbial interaction. The finding of neo-dolomite formed

  15. Substrate stiffness regulates extracellular matrix deposition by alveolar epithelial cells

    Directory of Open Access Journals (Sweden)

    Jessica L Eisenberg

    2011-01-01

    Full Text Available Jessica L Eisenberg1,2, Asmahan Safi3, Xiaoding Wei3, Horacio D Espinosa3, GR Scott Budinger2, Desire Takawira1, Susan B Hopkinson1, Jonathan CR Jones1,21Department of Cell and Molecular Biology, 2Division of Pulmonary Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; 3Department of Mechanical Engineering, Northwestern University, Evanston, IL, USAAim: The aim of the study was to address whether a stiff substrate, a model for pulmonary fibrosis, is responsible for inducing changes in the phenotype of alveolar epithelial cells (AEC in the lung, including their deposition and organization of extracellular matrix (ECM proteins.Methods: Freshly isolated lung AEC from male Sprague Dawley rats were seeded onto polyacrylamide gel substrates of varying stiffness and analyzed for expression and organization of adhesion, cytoskeletal, differentiation, and ECM components by Western immunoblotting and confocal immunofluorescence microscopy.Results: We observed that substrate stiffness influences cell morphology and the organization of focal adhesions and the actin cytoskeleton. Surprisingly, however, we found that substrate stiffness has no influence on the differentiation of type II into type I AEC, nor does increased substrate stiffness lead to an epithelial–mesenchymal transition. In contrast, our data indicate that substrate stiffness regulates the expression of the α3 laminin subunit by AEC and the organization of both fibronectin and laminin in their ECM.Conclusions: An increase in substrate stiffness leads to enhanced laminin and fibronectin assembly into fibrils, which likely contributes to the disease phenotype in the fibrotic lung.Keywords: alveolar epithelial cells, fibrosis, extracellular matrix, substrate stiffness

  16. Wetting of Au and Ag particles on monocrystalline graphite substrates

    Institute of Scientific and Technical Information of China (English)

    Joonho Lee; Toshihiro Tanaka; Kazufumi Seo; Nobumitsu Hirai; Jung-Goo Lee; Hirotaro Mori

    2006-01-01

    The wetting behavior of Au and Ag particles on a monocrystalline graphite substrate was investigated using the microscopic sessile drop method under a purified Ar atmosphere at 1300 K. The measured contact angles of the liquid Au and Ag on monocrystalline graphite substrates of (0001) face were 129° and 124°, respectively. It is believed that the interaction at the interface is dominated by the physical bonding (van der Waal's interaction).

  17. Coating-substrate-simulations applied to HFQ® forming tools

    Directory of Open Access Journals (Sweden)

    Leopold Jürgen

    2015-01-01

    Full Text Available In this paper a comparative analysis of coating-substrate simulations applied to HFQTM forming tools is presented. When using the solution heat treatment cold die forming and quenching process, known as HFQTM, for forming of hardened aluminium alloy of automotive panel parts, coating-substrate-systems have to satisfy unique requirements. Numerical experiments, based on the Advanced Adaptive FE method, will finally present.

  18. Microstructure of Bioglass/Hydroxyapatite Coatings on Ti Substrate

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Composite coatings of bioglass and hydroxyapatite (briefly named HA/BG) with different hydroxyapatite contents on titanium substrate were successfully fabricated. The fabricated coatings are characterized by rough and poriform surface. The densities of the coatings decrease with the increase of HA content. There is a transition layer with a 5 μm thickness between the BG coating and the substrate. During heat-treatment, hydroxyapatite crystals with hexastyle shape have precipitated from the BG.

  19. Droplets Fusion in a Microchannel on a Piezoelectric Substrate

    OpenAIRE

    Fu Xiang-ting; Zha Yan; Zhang An-liang

    2013-01-01

    Fusion droplets is a key operation in a microfluidic device for microfluidic analysis. A new fusion method for droplets was presented. An interditigal transducer and a reflector were fabricated on 1280-yx LiNbO3 piezoelectric substrate using microelectric technology. A poly-dimethyl silicone micro-channel was made by soft lithography technology and mounted on the piezoelectric substrate. Droplets in the microchannel were actuated by surface acoustic wave and fussed each other. Coloured dye so...

  20. Substrate-free gas-phase synthesis of graphene sheets.

    Science.gov (United States)

    Dato, Albert; Radmilovic, Velimir; Lee, Zonghoon; Phillips, Jonathan; Frenklach, Michael

    2008-07-01

    We present a novel method for synthesizing graphene sheets in the gas phase using a substrate-free, atmospheric-pressure microwave plasma reactor. Graphene sheets were synthesized by passing liquid ethanol droplets into an argon plasma. The graphene sheets were characterized by transmission electron microscopy, electron energy loss spectroscopy, Raman spectroscopy, and electron diffraction. We prove that graphene can be created without three-dimensional materials or substrates and demonstrate a possible avenue to the large-scale synthesis of graphene.

  1. Ultrasensitivity in phosphorylation-dephosphorylation cycles with little substrate.

    Directory of Open Access Journals (Sweden)

    Bruno M C Martins

    Full Text Available Cellular decision-making is driven by dynamic behaviours, such as the preparations for sunrise enabled by circadian rhythms and the choice of cell fates enabled by positive feedback. Such behaviours are often built upon ultrasensitive responses where a linear change in input generates a sigmoidal change in output. Phosphorylation-dephosphorylation cycles are one means to generate ultrasensitivity. Using bioinformatics, we show that in vivo levels of kinases and phosphatases frequently exceed the levels of their corresponding substrates in budding yeast. This result is in contrast to the conditions often required by zero-order ultrasensitivity, perhaps the most well known means for how such cycles become ultrasensitive. We therefore introduce a mechanism to generate ultrasensitivity when numbers of enzymes are higher than numbers of substrates. Our model combines distributive and non-distributive actions of the enzymes with two-stage binding and concerted allosteric transitions of the substrate. We use analytical and numerical methods to calculate the Hill number of the response. For a substrate with [Formula: see text] phosphosites, we find an upper bound of the Hill number of [Formula: see text], and so even systems with a single phosphosite can be ultrasensitive. Two-stage binding, where an enzyme must first bind to a binding site on the substrate before it can access the substrate's phosphosites, allows the enzymes to sequester the substrate. Such sequestration combined with competition for each phosphosite provides an intuitive explanation for the sigmoidal shifts in levels of phosphorylated substrate. Additionally, we find cases for which the response is not monotonic, but shows instead a peak at intermediate levels of input. Given its generality, we expect the mechanism described by our model to often underlay decision-making circuits in eukaryotic cells.

  2. Cultivation of Pleurotus on agricultural substrates in Cuba

    OpenAIRE

    R. C. Bermúdez; García, N.; Gross, P.; Serrano, M

    2001-01-01

    Pleurotus ostreatus f. sp. florida (P-184) was cultivated on several agricultural substrates, such as coffee pulp, cocoa shells, and coconut shells. These substrates were processed by solar drying, stored, pasteurized, and used for mushroom cultivation. The highest biological efficiencies were recorded on coffee pulp from Coffea arabica (168.5-179.4%), followed by coconut shells (90.0%), and cocoa shells (84.5%; particle size: > 4 mm).

  3. Colloidal quantum dot solar cells on curved and flexible substrates

    KAUST Repository

    Kramer, Illan J.

    2014-10-20

    © 2014 AIP Publishing LLC. Colloidal quantum dots (CQDs) are semiconductor nanocrystals synthesized with, processed in, and deposited from the solution phase, potentially enabling low-cost, facile manufacture of solar cells. Unfortunately, CQD solar cell reports, until now, have only explored batch-processing methods - such as spin-coating - that offer limited capacity for scaling. Spray-coating could offer a means of producing uniform colloidal quantum dot films that yield high-quality devices. Here, we explore the versatility of the spray-coating method by producing CQD solar cells in a variety of previously unexplored substrate arrangements. The potential transferability of the spray-coating method to a roll-to-roll manufacturing process was tested by spray-coating the CQD active layer onto six substrates mounted on a rapidly rotating drum, yielding devices with an average power conversion efficiency of 6.7%. We further tested the manufacturability of the process by endeavoring to spray onto flexible substrates, only to find that spraying while the substrate was flexed was crucial to achieving champion performance of 7.2% without compromise to open-circuit voltage. Having deposited onto a substrate with one axis of curvature, we then built our CQD solar cells onto a spherical lens substrate having two axes of curvature resulting in a 5% efficient device. These results show that CQDs deposited using our spraying method can be integrated to large-area manufacturing processes and can be used to make solar cells on unconventional shapes.

  4. Characterizing Protease Specificity: How Many Substrates Do We Need?

    Directory of Open Access Journals (Sweden)

    Michael Schauperl

    Full Text Available Calculation of cleavage entropies allows to quantify, map and compare protease substrate specificity by an information entropy based approach. The metric intrinsically depends on the number of experimentally determined substrates (data points. Thus a statistical analysis of its numerical stability is crucial to estimate the systematic error made by estimating specificity based on a limited number of substrates. In this contribution, we show the mathematical basis for estimating the uncertainty in cleavage entropies. Sets of cleavage entropies are calculated using experimental cleavage data and modeled extreme cases. By analyzing the underlying mathematics and applying statistical tools, a linear dependence of the metric in respect to 1/n was found. This allows us to extrapolate the values to an infinite number of samples and to estimate the errors. Analyzing the errors, a minimum number of 30 substrates was found to be necessary to characterize substrate specificity, in terms of amino acid variability, for a protease (S4-S4' with an uncertainty of 5 percent. Therefore, we encourage experimental researchers in the protease field to record specificity profiles of novel proteases aiming to identify at least 30 peptide substrates of maximum sequence diversity. We expect a full characterization of protease specificity helpful to rationalize biological functions of proteases and to assist rational drug design.

  5. Substrate and nutrient limitation regulating microbial growth in soil

    Science.gov (United States)

    Bååth, Erland

    2015-04-01

    Microbial activity and growth in soil is regulated by several abiotic factors, including temperature, moisture and pH as the most important ones. At the same time nutrient conditions and substrate availability will also determine microbial growth. Amount of substrate will not only affect overall microbial growth, but also affect the balance of fungal and bacterial growth. The type of substrate will also affect the latter. Furthermore, according to Liebig law of limiting factors, we would expect one nutrient to be the main limiting one for microbial growth in soil. When this nutrient is added, the initial second liming factor will become the main one, adding complexity to the microbial response after adding different substrates. I will initially describe different ways of determining limiting factors for bacterial growth in soil, especially a rapid method estimating bacterial growth, using the leucine incorporation technique, after adding C (as glucose), N (as ammonium nitrate) and P (as phosphate). Scenarios of different limitations will be covered, with the bacterial growth response compared with fungal growth and total activity (respiration). The "degree of limitation", as well as the main limiting nutrient, can be altered by adding substrate of different stoichiometric composition. However, the organism group responding after alleviating the nutrient limitation can differ depending on the type of substrate added. There will also be situations, where fungi and bacteria appear to be limited by different nutrients. Finally, I will describe interactions between abiotic factors and the response of the soil microbiota to alleviation of limiting factors.

  6. Modeling crawling cell movement on soft engineered substrates.

    Science.gov (United States)

    Löber, Jakob; Ziebert, Falko; Aranson, Igor S

    2014-03-07

    Self-propelled motion, emerging spontaneously or in response to external cues, is a hallmark of living organisms. Systems of self-propelled synthetic particles are also relevant for multiple applications, from targeted drug delivery to the design of self-healing materials. Self-propulsion relies on the force transfer to the surrounding. While self-propelled swimming in the bulk of liquids is fairly well characterized, many open questions remain in our understanding of self-propelled motion along substrates, such as in the case of crawling cells or related biomimetic objects. How is the force transfer organized and how does it interplay with the deformability of the moving object and the substrate? How do the spatially dependent traction distribution and adhesion dynamics give rise to complex cell behavior? How can we engineer a specific cell response on synthetic compliant substrates? Here we generalize our recently developed model for a crawling cell by incorporating locally resolved traction forces and substrate deformations. The model captures the generic structure of the traction force distribution and faithfully reproduces experimental observations, like the response of a cell on a gradient in substrate elasticity (durotaxis). It also exhibits complex modes of cell movement such as "bipedal" motion. Our work may guide experiments on cell traction force microscopy and substrate-based cell sorting and can be helpful for the design of biomimetic "crawlers" and active and reconfigurable self-healing materials.

  7. Accelerated endothelial wound healing on microstructured substrates under flow.

    Science.gov (United States)

    Franco, Davide; Milde, Florian; Klingauf, Mirko; Orsenigo, Fabrizio; Dejana, Elisabetta; Poulikakos, Dimos; Cecchini, Marco; Koumoutsakos, Petros; Ferrari, Aldo; Kurtcuoglu, Vartan

    2013-02-01

    Understanding and accelerating the mechanisms of endothelial wound healing is of fundamental interest for biotechnology and of significant medical utility in repairing pathologic changes to the vasculature induced by invasive medical interventions. We report the fundamental mechanisms that determine the influence of substrate topography and flow on the efficiency of endothelial regeneration. We exposed endothelial monolayers, grown on topographically engineered substrates (gratings), to controlled levels of flow-induced shear stress. The wound healing dynamics were recorded and analyzed in various configurations, defined by the relative orientation of an inflicted wound, the topography and the flow direction. Under flow perpendicular to the wound, the speed of endothelial regeneration was significantly increased on substrates with gratings oriented in the direction of the flow when compared to flat substrates. This behavior is linked to the dynamic state of cell-to-cell adhesions in the monolayer. In particular, interactions with the substrate topography counteract Vascular Endothelial Cadherin phosphorylation induced by the flow and the wounding. This effect contributes to modulating the mechanical connection between migrating cells to an optimal level, increasing their coordination and resulting in coherent cell motility and preservation of the monolayer integrity, thus accelerating wound healing. We further demonstrate that the reduction of vascular endothelial cadherin phosphorylation, through specific inhibition of Src activity, enhances endothelial wound healing in flows over flat substrates.

  8. Characterizing Protease Specificity: How Many Substrates Do We Need?

    Science.gov (United States)

    Schauperl, Michael; Fuchs, Julian E; Waldner, Birgit J; Huber, Roland G; Kramer, Christian; Liedl, Klaus R

    2015-01-01

    Calculation of cleavage entropies allows to quantify, map and compare protease substrate specificity by an information entropy based approach. The metric intrinsically depends on the number of experimentally determined substrates (data points). Thus a statistical analysis of its numerical stability is crucial to estimate the systematic error made by estimating specificity based on a limited number of substrates. In this contribution, we show the mathematical basis for estimating the uncertainty in cleavage entropies. Sets of cleavage entropies are calculated using experimental cleavage data and modeled extreme cases. By analyzing the underlying mathematics and applying statistical tools, a linear dependence of the metric in respect to 1/n was found. This allows us to extrapolate the values to an infinite number of samples and to estimate the errors. Analyzing the errors, a minimum number of 30 substrates was found to be necessary to characterize substrate specificity, in terms of amino acid variability, for a protease (S4-S4') with an uncertainty of 5 percent. Therefore, we encourage experimental researchers in the protease field to record specificity profiles of novel proteases aiming to identify at least 30 peptide substrates of maximum sequence diversity. We expect a full characterization of protease specificity helpful to rationalize biological functions of proteases and to assist rational drug design.

  9. Evaporation of sessile droplets on smooth and structured substrates

    Science.gov (United States)

    Colinet, Pierre; Flandroy, Marie; Dehaeck, Sam; Rednikov, Alexey; Sobac, Benjamin; Tsoumpas, Yannis

    2015-11-01

    Evaporation of sessile droplets remains a topic of active research nowadays, not only due to its widespread occurrence both in nature and technology, but also because it raises a number of interesting fundamental questions. Among these, the influence of the substrate topography is far from being understood. In this presentation, we focus on the difference between droplet evaporation dynamics on a smooth substrate and on substrates with controlled geometrical heterogeneities (square or hexagonal arrays of cylindrical pillars). While the wetting dynamics of droplets on such structured substrates has already been studied (in particular it is known that the droplet shape typically tends to adopt the symmetry of the pattern it lies upon), the influence the structure has on the evaporation dynamics (including the influence of pinning) has not yet received much attention. From interferometric measurements of droplet shapes, we highlight in particular that the evaporation from structured substrates is generally faster than on smooth substrates, and that the scaling exponents characterizing the evolution of radius versus time are also different. Pinning is also shown to be favored above a certain surface fraction of pillars, both for hexagonal and square arrays. Financial support of FRS-FNRS, ESA-BELSPO PRODEX, ULB, and BELSPO IAP 7/38 is gratefully acknowledged.

  10. Phosphotyrosine Substrate Sequence Motifs for Dual Specificity Phosphatases.

    Directory of Open Access Journals (Sweden)

    Bryan M Zhao

    Full Text Available Protein tyrosine phosphatases dephosphorylate tyrosine residues of proteins, whereas, dual specificity phosphatases (DUSPs are a subgroup of protein tyrosine phosphatases that dephosphorylate not only Tyr(P residue, but also the Ser(P and Thr(P residues of proteins. The DUSPs are linked to the regulation of many cellular functions and signaling pathways. Though many cellular targets of DUSPs are known, the relationship between catalytic activity and substrate specificity is poorly defined. We investigated the interactions of peptide substrates with select DUSPs of four types: MAP kinases (DUSP1 and DUSP7, atypical (DUSP3, DUSP14, DUSP22 and DUSP27, viral (variola VH1, and Cdc25 (A-C. Phosphatase recognition sites were experimentally determined by measuring dephosphorylation of 6,218 microarrayed Tyr(P peptides representing confirmed and theoretical phosphorylation motifs from the cellular proteome. A broad continuum of dephosphorylation was observed across the microarrayed peptide substrates for all phosphatases, suggesting a complex relationship between substrate sequence recognition and optimal activity. Further analysis of peptide dephosphorylation by hierarchical clustering indicated that DUSPs could be organized by substrate sequence motifs, and peptide-specificities by phylogenetic relationships among the catalytic domains. The most highly dephosphorylated peptides represented proteins from 29 cell-signaling pathways, greatly expanding the list of potential targets of DUSPs. These newly identified DUSP substrates will be important for examining structure-activity relationships with physiologically relevant targets.

  11. Motion and Arrest of a Molten Liquid on Cold Substrates

    Science.gov (United States)

    Tavakoli-Dastjerdi, Faryar

    Spreading of liquid drop on cold solid substrates followed by solidification involves heat transfer, fluid dynamics, and phase change physics. Coupling of these physical phenomena, although present in many industrial applications and nature, renders the physical understanding of the process challenging. Here, the key aspects of molten liquid spreading and solidifying on cold solid substrate are examined experimentally and theoretically. A novel hypothesis of spreading solidifying drops on cold solid substrates is introduced that emphasizes on early stages of the drop solidification at the solid-liquid-gas interface. The derived equations of the drop motion and arrest, stemmed from the development of the presented hypothesis, are in accord with obtained empirical results. The hypothesis is then thoroughly tested with new sets of experiments: i) Drop impact experiments, ii) Inclined plate experiments. In addition, the solidification of static supercooled drops and the initiation mechanism of an intermittent stage (recalescence) are addressed. Also, a peculiar delay-freezing property of hydrophobic surfaces is examined under varying liquid flow rates and substrate temperatures. Moreover, a new phenomenon of cold-induced spreading of water drops on hydrophobic surfaces due to premature condensation followed by thin-film formation at the trijunction is explored and the effect of physical parameters such as relative humidity, the substrate temperature, initial contact angle, surface roughness, and drop volume are investigated. This study will significantly advance the current understanding of dynamic interaction between molten liquid and cold solid substrates.

  12. Caged Protein Prenyltransferase Substrates: Tools for Understanding Protein Prenylation

    Energy Technology Data Exchange (ETDEWEB)

    DeGraw, Amanda J.; Hast, Michael A.; Xu, Juhua; Mullen, Daniel; Beese, Lorena S.; Barany, George; Distefano, Mark D. (Duke); (UMM)

    2010-11-15

    Originally designed to block the prenylation of oncogenic Ras, inhibitors of protein farnesyltransferase currently in preclinical and clinical trials are showing efficacy in cancers with normal Ras. Blocking protein prenylation has also shown promise in the treatment of malaria, Chagas disease and progeria syndrome. A better understanding of the mechanism, targets and in vivo consequences of protein prenylation are needed to elucidate the mode of action of current PFTase (Protein Farnesyltransferase) inhibitors and to create more potent and selective compounds. Caged enzyme substrates are useful tools for understanding enzyme mechanism and biological function. Reported here is the synthesis and characterization of caged substrates of PFTase. The caged isoprenoid diphosphates are poor substrates prior to photolysis. The caged CAAX peptide is a true catalytically caged substrate of PFTase in that it is to not a substrate, yet is able to bind to the enzyme as established by inhibition studies and X-ray crystallography. Irradiation of the caged molecules with 350 nm light readily releases their cognate substrate and their photolysis products are benign. These properties highlight the utility of those analogs towards a variety of in vitro and in vivo applications.

  13. Optimum selection of high performance mirror substrates for diamond finishing

    Science.gov (United States)

    Woodard, Kenneth S.; Comstock, Lovell E.; Wamboldt, Leonard; Sutherland, James S.

    2016-05-01

    Due to advances in manufacturing processes, the substrate options for high performance diamond machined mirrors are expanding. Fewer compromises have to be made to achieve the needed weight, stiffness and finish while maintaining reasonable costs. In addition to the traditional mirror materials like aluminum and beryllium, there are some less common materials that can now be included in the trade space that fill the cost and performance continuum between wrought aluminum and beryllium mirrors. Aluminum and beryllium, respectively, had been the low cost/fair performance and very high cost/very high performance bounds for substrate selection. These additional substrates provide multiple near net shape blank options and processes, mostly within these bounds, that can be considered in a mirror cost versus performance trade analysis. This paper will include a summary of some advances in manufacturing processes that provide more substrate options for diamond machined mirrors with some sample performance analysis and data. This is merged with the traditional substrate options to illustrate the now larger mirror substrate trade space. Some benchmark structural analysis is provided to back up a generic mirror design trade study.

  14. Identification of putative substrates for cynomolgus monkey cytochrome P450 2C8 by substrate depletion assays with 22 human P450 substrates and inhibitors.

    Science.gov (United States)

    Hosaka, Shinya; Murayama, Norie; Satsukawa, Masahiro; Uehara, Shotaro; Shimizu, Makiko; Iwasaki, Kazuhide; Iwano, Shunsuke; Uno, Yasuhiro; Yamazaki, Hiroshi

    2016-07-01

    Cynomolgus monkeys are widely used in drug developmental stages as non-human primate models. Previous studies used 89 compounds to investigate species differences associated with cytochrome P450 (P450 or CYP) function that reported monkey specific CYP2C76 cleared 19 chemicals, and homologous CYP2C9 and CYP2C19 metabolized 17 and 30 human CYP2C9 and/or CYP2C19 substrates/inhibitors, respectively. In the present study, 22 compounds selected from viewpoints of global drug interaction guidances and guidelines were further evaluated to seek potential substrates for monkey CYP2C8, which is highly homologous to human CYP2C8 (92%). Amodiaquine, montelukast, quercetin and rosiglitazone, known as substrates or competitive inhibitors of human CYP2C8, were metabolically depleted by recombinant monkey CYP2C8 at relatively high rates. Taken together with our reported findings of the slow eliminations of amodiaquine and montelukast by monkey CYP2C9, CYP2C19 and CYP2C76, the present results suggest that these at least four chemicals may be good marker substrates for monkey CYP2C8. Copyright © 2016 John Wiley & Sons, Ltd.

  15. Real-time sensing of epithelial cell-cell and cell-substrate interactions by impedance spectroscopy on porous substrates

    Energy Technology Data Exchange (ETDEWEB)

    Mondal, D.; RoyChaudhuri, C., E-mail: chirosreepram@yahoo.com [Department of Electronics and Telecommunication Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103 (India); Pal, D. [Department of Aerospace Engineering and Applied Mechanics, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103 (India)

    2015-07-28

    Oxidized porous silicon (PS) is a common topographical biocompatible substrate that potentially provides a distinct in vitro environment for better understanding of in vivo behavior. But in the reported studies on oxidized PS, cell-cell and cell-substrate interactions have been detected only by fluorescent labeling. This paper is the first attempt to investigate real-time sensing of these interactions on HaCaT cells by label-free impedance spectroscopy on oxidized PS of two pore diameters (50 and 500 nm). One of the major requirements for successful impedance spectroscopy measurement is to restrict the channeling of electric field lines through the pores. To satisfy this criterion, we have designed the pore depths after analyzing the penetration of the medium by using computational fluid dynamics simulation. A distributed electrical model was also developed for estimating the various cellular attributes by considering a pseudorandom distribution of pores. It is observed from the impedance measurements and from the model that the proliferation rate increases for 50 nm pores but decreases for 500 nm pores compared to that for planar substrates. The rate of decrease in cell substrate separation (h) in the initial stage is more than the rate of increase in cell-cell junction resistance (R{sub b}) corresponding to the initial adhesion phase of cells. It is observed that R{sub b} and h are higher for 50 nm pores than those for planar substrates, corresponding to the fact that substrates more conducive toward cell adhesion encourage cell-cell interactions than direct cell-substrate interactions. Thus, the impedance spectroscopy coupled with the proposed theoretical framework for PS substrates can sense and quantify the cellular interactions.

  16. Interactions between Casein kinase Iepsilon (CKIepsilon and two substrates from disparate signaling pathways reveal mechanisms for substrate-kinase specificity.

    Directory of Open Access Journals (Sweden)

    Caroline Lund Dahlberg

    Full Text Available BACKGROUND: Members of the Casein Kinase I (CKI family of serine/threonine kinases regulate diverse biological pathways. The seven mammalian CKI isoforms contain a highly conserved kinase domain and divergent amino- and carboxy-termini. Although they share a preferred target recognition sequence and have overlapping expression patterns, individual isoforms often have specific substrates. In an effort to determine how substrates recognize differences between CKI isoforms, we have examined the interaction between CKIepsilon and two substrates from different signaling pathways. METHODOLOGY/PRINCIPAL FINDINGS: CKIepsilon, but not CKIalpha, binds to and phosphorylates two proteins: Period, a transcriptional regulator of the circadian rhythms pathway, and Disheveled, an activator of the planar cell polarity pathway. We use GST-pull-down assays data to show that two key residues in CKIalpha's kinase domain prevent Disheveled and Period from binding. We also show that the unique C-terminus of CKIepsilon does not determine Dishevelled's and Period's preference for CKIepsilon nor is it essential for binding, but instead plays an auxillary role in stabilizing the interactions of CKIepsilon with its substrates. We demonstrate that autophosphorylation of CKIepsilon's C-terminal tail prevents substrate binding, and use mass spectrometry and chemical crosslinking to reveal how a phosphorylation-dependent interaction between the C-terminal tail and the kinase domain prevents substrate phosphorylation and binding. CONCLUSIONS/SIGNIFICANCE: The biochemical interactions between CKIepsilon and Disheveled, Period, and its own C-terminus lead to models that explain CKIepsilon's specificity and regulation.

  17. Shorty's Island Substrate Enhancement Pilot Project Extent, Kootenai River near Bonners Ferry, ID, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The substrate enhancement pilot project (SEPP) extent GIS layer represents an area where an artificial substrate will be placed. The artificial substrate, consisting...

  18. Myrtle Bend Substrate Enhancement Pilot Project Extent, Kootenai River near Bonners Ferry, ID, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The substrate enhancement pilot project (SEPP) extent GIS layer represents an area where an artificial substrate will be placed. The artificial substrate, consisting...

  19. Tribology of bio-inspired nanowrinkled films on ultrasoft substrates.

    Science.gov (United States)

    Lackner, Juergen M; Waldhauser, Wolfgang; Major, Lukasz; Teichert, Christian; Hartmann, Paul

    2013-01-01

    Biomimetic design of new materials uses nature as antetype, learning from billions of years of evolution. This work emphasizes the mechanical and tribological properties of skin, combining both hardness and wear resistance of its surface (the stratum corneum) with high elasticity of the bulk (epidermis, dermis, hypodermis). The key for combination of such opposite properties is wrinkling, being consequence of intrinsic stresses in the bulk (soft tissue): Tribological contact to counterparts below the stress threshold for tissue trauma occurs on the thick hard stratum corneum layer pads, while tensile loads smooth out wrinkles in between these pads. Similar mechanism offers high tribological resistance to hard films on soft, flexible polymers, which is shown for diamond-like carbon (DLC) and titanium nitride thin films on ultrasoft polyurethane and harder polycarbonate substrates. The choice of these two compared substrate materials will show that ultra-soft substrate materials are decisive for the distinct tribological material. Hierarchical wrinkled structures of films on these substrates are due to high intrinsic compressive stress, which evolves during high energetic film growth. Incremental relaxation of these stresses occurs by compound deformation of film and elastic substrate surface, appearing in hierarchical nano-wrinkles. Nano-wrinkled topographies enable high elastic deformability of thin hard films, while overstressing results in zigzag film fracture along larger hierarchical wrinkle structures. Tribologically, these fracture mechanisms are highly important for ploughing and sliding of sharp and flat counterparts on hard-coated ultra-soft substrates like polyurethane. Concentration of polyurethane deformation under the applied normal loads occurs below these zigzag cracks. Unloading closes these cracks again. Even cyclic testing do not lead to film delamination and retain low friction behavior, if the adhesion to the substrate is high and the initial

  20. Film-substrate hydrodynamic interaction initiated by femtosecond laser irradiation

    Science.gov (United States)

    Khokhlov, V. A.; Inogamov, N. A.; Zhakhovsky, V. V.; Ilnitsky, D. K.; Migdal, K. P.; Shepelev, V. V.

    2017-01-01

    Action of an ultrashort single laser pulse onto a thin metal film is considered. Disruption of a plane freestanding film quickly heated by a laser is the simplest model of the laser thermomechanical spallation. There is a sharp spallation (ablation) threshold Fabl dividing dynamics of a freestanding film to two regimes: below or above the threshold Fabl. Problem of significant importance is: how this picture will change when a film is deposited onto a substrate? We have solved this problem. It is found that there are two thresholds Fdelam < F < Fabl and the four regimes of motion relative to the case of a freestanding film. For the range of fluences 0 < F < Fdelam a film oscillates remaining on a substrate. Oscillations decay in time due to irradiation of the sonic waves into substrate. For Fdelam < F < Fabl + ΔF the film delaminates from the substrate because negative pressure (tensile stress) propagating from the vacuum boundary with the rarefaction acoustic wave achieves the film-substrate contact boundary and overcomes adhesion strength of a contact. The addition ΔF to the freestanding case is small in the case when the ratio η of the acoustic impedances of substrate to a film is small. This is the case of the gold or silver films on a glass. The third is the complicated regime with interacting delamination and spallation processes when F ≈ Fabl + ΔF. In the fourth regime Fabl + ΔF < F there is the disruption of a film into two halves. The external half flies away while the internal one remains on substrate.

  1. The influence of substrate on DNA transfer and extraction efficiency.

    Science.gov (United States)

    Verdon, Timothy J; Mitchell, R John; van Oorschot, Roland A H

    2013-01-01

    The circumstances surrounding deposition of DNA profiles are increasingly becoming an issue in court proceedings, especially whether or not the deposit was made by primary transfer. In order to improve the currently problematic evaluation of transfer scenarios in court proceedings, we examined the influence a variety of nine substrate types (six varieties of fabric, plywood, tarpaulin, and plastic sheets) has on DNA transfer involving blood. DNA transfer percentages were significantly higher (p=0.03) when the primary substrate was of non-porous material (such as tarpaulin, plastic or, to a lesser degree, wood) and the secondary substrate porous (such as fabrics). These findings on transfer percentages confirm the results of previous studies. Fabric composition was also shown to have a significant (p=0.03) effect on DNA transfer; when experiments were performed with friction from a variety of fabrics to a specific weave of cotton, transfer percentages ranged from 4% (flannelette) to 94% (acetate). The propensity for the same nine substrates to impact upon the efficiency of DNA extraction procedures was also examined. Significant (p=0.03) differences were found among the extraction efficiencies from different materials. When 15μL of blood was deposited on each of the substrates, the lowest quantity of DNA was extracted from plastic (20ng) and the highest quantities extracted from calico and flannelette (650ng). Significant (pDNA extraction yield from different initial blood volumes from all substrates. Also, significantly greater (pDNA was seen during concentration of extracts with higher compared to lower initial quantities of DNA. These findings suggest that the efficiency of extraction and concentration impacts upon the final amount of DNA available for analysis and that consideration of these effects should not be ignored. The application of correction factors to adjust for any variation among extraction and concentration efficiencies among substrates is

  2. Substrate stiffness regulates filopodial activities in lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Yu-Ren Liou

    Full Text Available Microenvironment stiffening plays a crucial role in tumorigenesis. While filopodia are generally thought to be one of the cellular mechanosensors for probing environmental stiffness, the effects of environmental stiffness on filopodial activities of cancer cells remain unclear. In this work, we investigated the filopodial activities of human lung adenocarcinoma cells CL1-5 cultured on substrates of tunable stiffness using a novel platform. The platform consists of an optical system called structured illumination nano-profilometry, which allows time-lapsed visualization of filopodial activities without fluorescence labeling. The culturing substrates were composed of polyvinyl chloride mixed with an environmentally friendly plasticizer to yield Young's modulus ranging from 20 to 60 kPa. Cell viability studies showed that the viability of cells cultured on the substrates was similar to those cultured on commonly used elastomers such as polydimethylsiloxane. Time-lapsed live cell images were acquired and the filopodial activities in response to substrates with varying degrees of stiffness were analyzed. Statistical analyses revealed that lung cancer cells cultured on softer substrates appeared to have longer filopodia, higher filopodial densities with respect to the cellular perimeter, and slower filopodial retraction rates. Nonetheless, the temporal analysis of filopodial activities revealed that whether a filopodium decides to extend or retract is purely a stochastic process without dependency on substrate stiffness. The discrepancy of the filopodial activities between lung cancer cells cultured on substrates with different degrees of stiffness vanished when the myosin II activities were inhibited by treating the cells with blebbistatin, which suggests that the filopodial activities are closely modulated by the adhesion strength of the cells. Our data quantitatively relate filopodial activities of lung cancer cells with environmental stiffness and

  3. TRIBOLOGY OF BIO-INSPIRED NANOWRINKLED FILMS ON ULTRASOFT SUBSTRATES

    Directory of Open Access Journals (Sweden)

    Juergen M. Lackner

    2013-03-01

    Full Text Available Biomimetic design of new materials uses nature as antetype, learning from billions of years of evolution. This work emphasizes the mechanical and tribological properties of skin, combining both hardness and wear resistance of its surface (the stratum corneum with high elasticity of the bulk (epidermis, dermis, hypodermis. The key for combination of such opposite properties is wrinkling, being consequence of intrinsic stresses in the bulk (soft tissue: Tribological contact to counterparts below the stress threshold for tissue trauma occurs on the thick hard stratum corneum layer pads, while tensile loads smooth out wrinkles in between these pads. Similar mechanism offers high tribological resistance to hard films on soft, flexible polymers, which is shown for diamond-like carbon (DLC and titanium nitride thin films on ultrasoft polyurethane and harder polycarbonate substrates. The choice of these two compared substrate materials will show that ultra-soft substrate materials are decisive for the distinct tribological material. Hierarchical wrinkled structures of films on these substrates are due to high intrinsic compressive stress, which evolves during high energetic film growth. Incremental relaxation of these stresses occurs by compound deformation of film and elastic substrate surface, appearing in hierarchical nano-wrinkles. Nano-wrinkled topographies enable high elastic deformability of thin hard films, while overstressing results in zigzag film fracture along larger hierarchical wrinkle structures. Tribologically, these fracture mechanisms are highly important for ploughing and sliding of sharp and flat counterparts on hard-coated ultra-soft substrates like polyurethane. Concentration of polyurethane deformation under the applied normal loads occurs below these zigzag cracks. Unloading closes these cracks again. Even cyclic testing do not lead to film delamination and retain low friction behavior, if the adhesion to the substrate is high

  4. Oriented growth and assembly of zeolite crystals on substrates

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ming; ZHANG BaoQuan; LIU XiuFeng

    2008-01-01

    The aligned array and thin film of zeolites and molecular sieves possess a variety of potential applica-tions in membrane separation and catalysis, chemical sensors, and microelectronic devices. There are two main synthesis methods for manufacturing the aligned arrays and thin films of zeolites and mo-lecular sieves, i.e. in situ hydrothermal reaction and self-assembly of crystal grains on substrates. Both of them have attracted much attention in the scientific community worldwide. A series of significant progress has been made in recent years. By the in situ hydrothermal synthesis, the oriented nucleation and growth of zeolite and molecular sieve crystals can be achieved by modifying the surface properties of substrates or by changing the composition of synthesis solutions, leading to the formation of uni-formly oriented multicrystal-aligned arrays or thin films. On the other hand, the crystal grains of zeo-lites and molecular sieves can be assembled onto the substrate surface in required orientation using different bondages, for instance, the microstructure in the array or thin film can be controlled. This review is going to summarize and comment the significant results and progress reported recently in manufacturing highly covered and uniformly aligned arrays or thin films of zeolites and molecular sieves. It involves (1) in situ growth of highly aligned zeolite arrays and thin films via embedding func-tional groups on the substrate surface, modifying the surface microstructure of substrates, as well as varying the composition of synthesis solutions; (2) assembly of zeolite and molecular sieve crystals on various substrates to form aligned arrays and thin films with full coverage by covalent, ionic, and in-termolecular coupling interactions between crystals and substrates; (3) coupling surface assembly with microcontact printing or photoetching technique to produce patterned zeolite arrays and thin films. Finally, the functionality and applications of zeolite

  5. Ligand Binding and Substrate Discrimination by UDP-Galactopyranose Mutase

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, Todd D.; Borrok, M. Jack; Westler, William M.; Forest, Katrina T.; Kiessling, Laura L.; (UW)

    2009-07-31

    Galactofuranose (Galf) residues are present in cell wall glycoconjugates of numerous pathogenic microbes. Uridine 5{prime}-diphosphate (UDP) Galf, the biosynthetic precursor of Galf-containing glycoconjugates, is produced from UDP-galactopyranose (UDP-Galp) by the flavoenzyme UDP-galactopyranose mutase (UGM). The gene encoding UGM (glf) is essential for the viability of pathogens, including Mycobacterium tuberculosis, and this finding underscores the need to understand how UGM functions. Considerable effort has been devoted to elucidating the catalytic mechanism of UGM, but progress has been hindered by a lack of structural data for an enzyme-substrate complex. Such data could reveal not only substrate binding interactions but how UGM can act preferentially on two very different substrates, UDP-Galp and UDP-Galf, yet avoid other structurally related UDP sugars present in the cell. Herein, we describe the first structure of a UGM-ligand complex, which provides insight into the catalytic mechanism and molecular basis for substrate selectivity. The structure of UGM from Klebsiella pneumoniae bound to the substrate analog UDP-glucose (UDP-Glc) was solved by X-ray crystallographic methods and refined to 2.5 {angstrom} resolution. The ligand is proximal to the cofactor, a finding that is consistent with a proposed mechanism in which the reduced flavin engages in covalent catalysis. Despite this proximity, the glucose ring of the substrate analog is positioned such that it disfavors covalent catalysis. This orientation is consistent with data indicating that UDP-Glc is not a substrate for UGM. The relative binding orientations of UDP-Galp and UDP-Glc were compared using saturation transfer difference NMR. The results indicate that the uridine moiety occupies a similar location in both ligand complexes, and this relevant binding mode is defined by our structural data. In contrast, the orientations of the glucose and galactose sugar moieties differ. To understand the

  6. Raman discrimination of bacterial strains using multilayered microcavity substrates

    Science.gov (United States)

    Sharma, Shiv K.; Dykes, Ava C.; Misra, Anupam K.; Kamemoto, Lori E.; Bates, David E.

    2011-05-01

    Surface-enhanced Raman scattering (SERS) utilizing colloidal silver and gold has been demonstrated to provide a rapid means of measuring the Raman spectra of microorganisms in the fingerprint region. In this study, we have introduced microcavity substrates coated with alternating layers of silver and gold thin films for measuring the Raman spectra of four strains of E. coli. These microcavitiy substrates have been prepared by placing glass microspheres between two polished aluminum substrates and pressing them together using a standard lab press. After removing the glass microspheres from the substrates, the substrates have been coated with 15 to 70 nm thick films of chromium, silver and gold in a precise order. The cavities were evaluated for SERS enhancement by measuring Raman spectra of dilute rhodamine 6G (R6G) down to 10-8 M. With these microcavities, we have investigated the SERS spectra of four chemically competent strains of E. coli (One Shot OmniMAX 2-T1, Mach1-T1, Stbl3, and TOP10). Replicate SERS spectra of all the four e-coli strains show excellent reproducibility. Visual examination of the spectra, however, reveals differences in the spectra of these strains. To confirm this observation, we have used multivariate analysis for positive identification and discrimination between the strains.

  7. Effect Of Various Substrates On Eudrilus eugeniae (Oligochaeta Production

    Directory of Open Access Journals (Sweden)

    Mpoame, M.

    1994-01-01

    Full Text Available In order to assess the effects of substrate on Eudrilus eugeniae production, 360 worms were raised in plastic buckets containing manure either from cattle (BV, from sheep (CM, from rabbit (CL, and from chicken (FP. At the end of the experiment which lasted 4 months, worm productivity was estimated at 111.9 g/kg of substrate in CL, 86.3 g/kg in CM, and 33.0 g/kg in BV. Substrate FP was inadequate as worms escaped from it. In another trial aiming at determining some of E. Eugeniae's reproductive parameters, each of the 3 substrates BV, CL, and CM was distributed into 15 plastic half bottles and was inoculated with one cocoon. In the 3 substrates cocoon incubation time and growing period were estimated at 3 to 4 weeks and 6 to 7 weeks respectively. Cocoons were laid approximately a week after the pairing of worms. On the average, each worm laid 2 cocoons per week.

  8. A model of cytoskeletal reorientation in response to substrate stretching

    Directory of Open Access Journals (Sweden)

    Lazopoulos K.A.

    2008-01-01

    Full Text Available Living adherent cells change their orientation in response to substrate stretching such that their cytoskeletal components reorganize in a new direction. To study this phenomenon, we model the cytoskeleton as a planar system of elastic cables and struts both pinned at their endpoints to a flat flexible substrate. Tensed (pre-strained cables represent acting stress fibers, whereas compression-bearing struts represent microtubules. We assume that in response to uniaxial substrate stretching the model reorients and deforms into a new configuration that minimizes its total potential energy. Using the Maxwell's global stability criterion, we find global minima configurations during static extension and compression of the substrate. Based on these results, we predict reorientation during cyclic stretching of the substrate. We find that in response to cyclic stretching cells either reorient transversely to the direction of stretching, or exhibit multiple configurations symmetrically distributed relative to the direction of stretching. These predictions are consistent with experimental data on living cells from the literature.

  9. Unique Gold Nanoparticle Aggregates as a Highly Active SERS Substrate

    Energy Technology Data Exchange (ETDEWEB)

    Schwartzberg, A M; Grant, C D; Wolcott, A; Talley, C E; Huser, T R; Bogomolni, R; Zhang, J Z

    2004-04-06

    A unique gold nanoparticle aggregate (GNA) system has been shown to be an excellent substrate for surface-enhanced Raman scattering (SERS) applications. Rhodamine 6G (R6G), a common molecule used for testing SERS activity on silver, but generally difficult to detect on gold substrates, has been found to readily bind to the GNA and exhibit strong SERS activity due to the unique surface chemistry afforded by sulfur species on the surface. This GNA system has yielded a large SERS enhancement of 10{sup 7}-10{sup 9} in bulk solution for R6G, on par with or greater than any previously reported gold SERS substrate. SERS activity has also been successfully demonstrated for several biological molecules including adenine, L-cysteine, L-lysine, and L-histidine for the first time on a gold SERS substrate, showing the potential of this GNA as a convenient and powerful SERS substrate for biomolecular detection. In addition, SERS spectrum of R6G on single aggregates has been measured. We have shown that the special surface properties of the GNA, in conjunction with strong near IR absorption, make it useful for SERS analysis of a wide variety of molecules.

  10. Gecko Adhesion on Wet and Dry Patterned Substrates.

    Science.gov (United States)

    Stark, Alyssa Y; Palecek, Amanda M; Argenbright, Clayton W; Bernard, Craig; Brennan, Anthony B; Niewiarowski, Peter H; Dhinojwala, Ali

    2015-01-01

    Perhaps one of the most astounding characteristics of the gecko adhesive system is its versatility. Geckos can locomote across complex substrates in a variety of conditions with apparent ease. In contrast, many of our synthetic pressure sensitive adhesives fail on substrates that are dirty, wet or rough. Although many studies have investigated the effect of environmental challenges on performance, the interaction of multiple, potentially compromising variables is studied less often. Here we focus on substrate structure and surface water, both of which are highly relevant to the biological system and to synthetic design. To do this we utilized a highly controlled, patterned substrate (Sharklet®, by Sharklet® Technologies Inc.). This allowed us to test independently and jointly the effects of reduced surface area substrates, with a defined pattern, on adhesion in both air and water. Our results show that adhesion is not significantly impaired in air, whereas surface area and pattern significantly affect adhesion in water. These findings highlight the need to study multiple parameters that are relevant to the gecko adhesive system to further improve our understanding of the biological system and to design better, more versatile synthetics.

  11. Gecko Adhesion on Wet and Dry Patterned Substrates.

    Directory of Open Access Journals (Sweden)

    Alyssa Y Stark

    Full Text Available Perhaps one of the most astounding characteristics of the gecko adhesive system is its versatility. Geckos can locomote across complex substrates in a variety of conditions with apparent ease. In contrast, many of our synthetic pressure sensitive adhesives fail on substrates that are dirty, wet or rough. Although many studies have investigated the effect of environmental challenges on performance, the interaction of multiple, potentially compromising variables is studied less often. Here we focus on substrate structure and surface water, both of which are highly relevant to the biological system and to synthetic design. To do this we utilized a highly controlled, patterned substrate (Sharklet®, by Sharklet® Technologies Inc.. This allowed us to test independently and jointly the effects of reduced surface area substrates, with a defined pattern, on adhesion in both air and water. Our results show that adhesion is not significantly impaired in air, whereas surface area and pattern significantly affect adhesion in water. These findings highlight the need to study multiple parameters that are relevant to the gecko adhesive system to further improve our understanding of the biological system and to design better, more versatile synthetics.

  12. General frost growth mechanism on solid substrates with different stiffness.

    Science.gov (United States)

    Petit, Julien; Bonaccurso, Elmar

    2014-02-01

    Preventing or delaying frost formation on surfaces is of significant importance in many aspects of our daily life. Despite many efforts and improvements recently achieved in the design of new icephobic materials and substrates, not all proposed solutions are universally applicable and frost formation still remains a problem in need of further flexible solutions. In this respect, we propose to take benefit from the tunable viscoelastic properties of soft polymer gel substrates, since they are known to strongly influence the dropwise condensation process of water, and to investigate condensation frosting on them. Using polymer gels with different stiffness and a hard substrate as a reference, we demonstrate their ability to delay frost formation compared to recent results reported in the literature on other solid substrates and in particular on superhydrophobic surfaces. By investigating the frost front propagation we singled out a general behavior of its dynamic evolution consisting of two processes presenting two different time scales. This general growth appears to be independent of experimental conditions as well as substrate stiffness.

  13. Synthesis and evaluation of fluorogenic triglycerides as lipase assay substrates.

    Science.gov (United States)

    Andersen, Rokhsana J; Brask, Jesper

    2016-06-01

    Three racemic fluorogenic triglycerides are synthesized and evaluated as lipase assay substrates. The presented synthesis route goes through a key triglyceride intermediate which can be chemoselectively functionalized with a wide range of different probes. Hence the substrate can be tailor-made for a specific assay, or focus can be on low cost in larger scale for applications in high-throughput screening (HTS) assays. In the specific examples, TG-ED, TG-FD and TG-F2 are assembled with the Edans-Dabcyl or the fluorescein-Dabcyl FRET pair, or relying on fluorescein self-quenching, respectively. Proof-of-concept assays allowed determination of 1st order kinetic parameters (kcat/KM) of 460s(-1)M(-1), 59s(-1)M(-1) and 346s(-1)M(-1), respectively, for the three substrates. Commercially available EnzChek lipase substrate provided 204s(-1)M(-1). Substrate concentration was identified as a critical parameter, with measured reaction rates decreasing at higher concentrations when intermolecular quenching becomes significant.

  14. Adhesion, growth, and matrix production by fibroblasts on laminin substrates

    DEFF Research Database (Denmark)

    Couchman, J R; Höök, M; Rees, D A;

    1983-01-01

    Human embryonic skin fibroblasts have been shown to attach and spread on laminin substrates in the absence of protein synthesis and presence of fibronectin-depleted serum and anti-fibronectin antibodies. Rates of attachment and the type of spreading are virtually identical on fibronectin and lami......Human embryonic skin fibroblasts have been shown to attach and spread on laminin substrates in the absence of protein synthesis and presence of fibronectin-depleted serum and anti-fibronectin antibodies. Rates of attachment and the type of spreading are virtually identical on fibronectin...... and laminin-coated substrates with the development of microfilament bundles and focal adhesions. Antibodies to laminin, but not fibronectin, will prevent or reverse fibroblast adhesion to laminin, whereas antibodies to fibronectin but not laminin will give similar results on fibronectin-coated substrates....... These and other results indicate that fibroblasts possess distinct receptors for laminin and fibronectin which on contact with suitable substrates promote adhesion through interaction with common intermediates. This type of adhesion is compatible with subsequent growth and extracellular matrix production....

  15. Growth of brass nanofilms sputtered on organic substrate

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhen-xing; WANG Ling-sen; HUANG Bai-yun

    2005-01-01

    The growth of brass nanofilms sputtered on acrylics substrate was studied through experimental investigation of the effect of sputtering voltage, target-to-substrate distance, chamber pressure and sputtering time on the content, growth rate and surface morphology of brass nanofilms. The results show that compared with original brass target, Cu content in brass nanofilms changes by no more than 6.23% (mass fraction). High sputtering voltage and short target-to-substrate distance help to improve brass nanofilm deposition rate. There exists an optimal chamber pressure where deposition rate of nanofilm reaches the maximum. The key factor affecting surface morphology is the kinetic energy of sputtering particles. Low sputtering voltage, large target-to-substrate distance and low chamber pressure are very important for the formation of the high-quality brass nanofilms. The brass films prepared under the conditions of sputtering voltage 1.6 kV, target-to-substrate distance 2.5 cm, chamber pressure 10 Pa and sputtering time 20 min, possess following characteristics: smooth and uniform surface, thickness of 41 nm and Cu content of 71.0% (mass fraction).

  16. A liquid aluminum corrosion resistance surface on steel substrate

    Energy Technology Data Exchange (ETDEWEB)

    Wang Deqing; Shi Ziyuan; Zou Longjiang

    2003-05-31

    The process of hot dipping pure aluminum on a steel substrate followed by oxidation was studied to form a surface layer of aluminum oxide resistant to the corrosion of aluminum melt. The thickness of the pure aluminum layer on the steel substrate is reduced with the increase in temperature and time in initial aluminizing, and the thickness of the aluminum layer does not increase with time at given temperature when identical temperature and complete wetting occur between liquid aluminum and the substrate surface. The thickness of the Fe-Al intermetallic layer on the steel base is increased with increasing bath temperature and time. Based on the experimental data and the mathematics model developed by the study, a maximum exists in the thickness of the Fe-Al intermetallic at certain dipping temperature. X-ray diffraction (XRD) and energy dispersive X-ray (EDX) analysis reveals that the top portion of the steel substrate is composed of a thin layer of {alpha}-Al{sub 2}O{sub 3}, followed by a thinner layer of FeAl{sub 3}, and then a much thicker one of Fe{sub 2}Al{sub 5} on the steel base side. In addition, there is a carbon enrichment zone in diffusion front. The aluminum oxide surface formed on the steel substrate is in perfect condition after corrosion test in liquid aluminum at 750 deg. C for 240 h, showing extremely good resistance to aluminum melt corrosion.

  17. Laser-induced backside wet cleaning technique for glass substrates

    Science.gov (United States)

    Weng, Tsu-Shien; Tsai, Chwan-Huei

    2014-08-01

    The aim of this paper is to study the laser-induced backside wet cleaning techniques for glass substrates. Two kinds of laser cleaning techniques are proposed in this study. The first involves applying an Nd:YAG laser to the backside of the substrate which is submerged in water. A metal plate is placed below the glass substrate. Most of the laser energy will be absorbed by the metal plate. The metal then vaporizes the water and generates a turbulent bubble flow. The bubble flow removes the alumina particles from the surface of the glass substrate. The second involves using a CO2 laser to generate turbulent bubble flow to remove the particles. Both methods were successfully demonstrated for the removal of submicron particles of 0.5 μm in size. The phenomena of bubble generation and diffusion are presented in the paper. Because the laser is applied to the backside of the substrate, the damage due to the laser heat can be significantly reduced. The quality and efficient of the backside processing is better than those of the front side processing. The proposed techniques have great potential to provide an improved solution for glass cleaning.

  18. Substrate utilization by Campylobacter jejuni and Campylobacter coli

    Energy Technology Data Exchange (ETDEWEB)

    Westfall, H.N.; Rollins, D.M.; Weiss, E.

    1986-10-01

    An attempt was made to elucidate in Campylobacter spp. some of the physiologic characteristics that are reflected in the kinetics of CO/sub 2/ formation from four /sup 14/C-labeled substrates. Campylobacter jejuni and C. coli were grown in a biphasic medium, and highly motile spiral cells were harvested at 12 h. The cells were incubated with 0.02 M glutamate, glutamine, ..cap alpha..-ketoglutarate, or formate, or with concentrations of these substrates ranging from 0.0032 to 0.125 M. All four substrates were metabolized very rapidly by both species. A feature of many of these reactions, particularly obvious with /sup 2/chemically bond-ketoglutarate, was an immediate burst of CO/sub 2/ production followed by CO/sub 2/ evolution at a more moderate rate. These diphasic kinetics of substrate utilization were not seen in comparable experiments with Escherichia coli grown and tested under identical conditions. With C. jejuni, CO/sub 2/ production from formate proceeded rapidly for the entire period of incubation. The rate of metabolism of glutamate, glutamine, and ..cap alpha..-ketoglutarate by both species was greatly enhanced by increased substrate concentration. The approach to the study of the metabolism of campylobacters here described may be useful in detecting subtle changes in the physiology of cells as they are maintained past their logarithmic growth phase.

  19. Silicon solar cells with low-cost substrates

    Energy Technology Data Exchange (ETDEWEB)

    Kotval, P.S.; Strock, H.B.

    1978-11-07

    Epitaxial and diffusion-type planar diodes and solar cells utilize low-cost refined metallurgical silicon substrates having a substantially higher impurity content than conventional high-cost, high purity semiconductor grade silicon. The epitaxial type products have an n-on-p-on-p substrate configuration, while the diffusion-type products have pentavalent impurities diffused therein to form a p-n junction in the low cost silicon substrate. One embodiment employs a multigrained refined metallurgical silicon (RMS) prepared by precipitating essentially iron-free silicon platelets from a solution of metallurgical grade silicon in molten aluminum, melting said refined platelets, in contact with a silica slag and pulling silicon boules from a melt of said refined metallurgical silicon (RMS). By directionally solidifying the refined silicon--slag melt, a multigrained, directionally solidified refined metallurgical silicon (DS/RMS) is obtained, with boules being pulled from a melt thereof for use as said low-cost substrate. The DS/RMS may also be re-melted and directionally solidified a second time with the boules being pulled from said twice directionally solidified material being a desirable, low-cost, single crystal material suitable for use as said substrate for planar diode and solar cell applications.

  20. Substrate specificity of the neuraminidase of different mumps virus strains.

    Science.gov (United States)

    Klamm, H; Pollex, G

    1984-11-01

    The hydrolysis of neuraminlactose, fetuin, ovomucoid, kappa-caseinglycopeptide and mucine from the bovine submaxillary gland with the neuraminidase (NA) of mumps virus strains Jeryl Lynn, Enders and Berlin 9/76 was investigated to determine the pH-dependence of the reaction with the different substrates. The corresponding curves showed splitting into several peaks with reaction maxima ranging from pH 4.7 to pH 6.7. This occurred probably due to the heterogeneity of the virus samples. The NA of each virus strain had the best reaction affinity to neuraminlactose followed by decreasing affinities to ovomucoid, fetuin and kappa-caseinglycopeptide. The mucine from bovine submaxillary gland was not digested at all. The highest hydrolysis of each substrate was found with the Jeryl Lynn strain, which also possessed the lowest substrate specificity. It was followed by that of strain Enders and finally by isolate Berlin 9/76 which, in turn, had the highest substrate specificity. The lower substrate specificity of mumps virus NA seemed to correlate with a lower degree of its cytopathogenicity for hamster ependyma cells.

  1. Heterogeneous nucleation on potent spherical substrates during solidification

    Energy Technology Data Exchange (ETDEWEB)

    Ma Qian [BCAST - Brunel Centre for Advanced Solidification Technology, Brunel University, West London UB8 3PH (United Kingdom)]. E-mail: ma.qian@brunel.ac.uk

    2007-02-15

    For a spherical-cap nucleus to become a 'transformation nucleus', the linear dimension (d) of the flat substrate must exceed the critical nucleus size (2r *). This Turnbull criterion (d {>=} 2r *) defines a minimum undercooling for grain formation on, and effective inoculation with, flat nucleating substrates. However, for nucleation on potent substrates the spherical-cap model is no longer tenable. The free growth model has in general considered the growth of a two-dimensional nucleus on a potent flat substrate. Inspired by the particle-core structures observed in magnesium alloys after inoculation with nearly spherical zirconium particles, a model has been proposed, on the basis of an adsorption and surface diffusion mechanism, for heterogeneous nucleation and grain formation on potent spherical substrates of d {>=} 2r *. The critical undercooling required is found to be approximately the same as that defined by Turnbull's patch nucleation theory. The model shows excellent agreement with experiments compared from different perspectives.

  2. Tailoring optical forces for nanoparticle manipulation on layered substrates

    Science.gov (United States)

    Salary, Mohammad M.; Mosallaei, Hossein

    2016-07-01

    Optical forces can be used to manipulate small particles through various mechanisms. In this paper, we present a comprehensive analysis of optical forces acting on the nanoparticles located over a substrate using different manipulation techniques, as well as the conditions of the optimization of these forces. In particular, we study optical trapping, acceleration, and binding. Calculations are carried out using the exact multipole expansion method combined with Maxwell stress tensor formalism, providing a general framework to study optical forces on particles for arbitrary incident fields using closed-form expressions. The method takes into account multiple scattering between the particles and substrate and allows clear predictive abilities well beyond the dipole model. We consider the interaction of dielectric and metallic nanoparticles with various substrates. The presence of substrate is shown to have a significant impact on the nanoparticles' resonances and provides an additional degree of freedom in tailoring the optical forces. We explore different physical processes contributing to the optical force and their interplay on the mobility of the particle. It is established that engineering layered substrates can broaden the scope of trapping and acceleration and enhance the binding forces. It can also provide a high tunability of the acceleration direction. The analysis presented in this paper provides key physical insights to identify optimum setup for nanoparticles manipulation in various applications.

  3. Biological Effects of Culture Substrates on Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Yohei Hayashi

    2016-01-01

    Full Text Available In recent years, as human pluripotent stem cells (hPSCs have been commonly cultured in feeder-free conditions, a number of cell culture substrates have been applied or developed. However, the functional roles of these substrates in maintaining hPSC self-renewal remain unclear. Here in this review, we summarize the types of these substrates and their effect on maintaining hPSC self-renewal. Endogenous extracellular matrix (ECM protein expression has been shown to be crucial in maintaining hPSC self-renewal. These ECM molecules interact with integrin cell-surface receptors and transmit their cellular signaling. We discuss the possible effect of integrin-mediated signaling pathways on maintaining hPSC self-renewal. Activation of integrin-linked kinase (ILK, which transmits ECM-integrin signaling to AKT (also known as protein kinase B, has been shown to be critical in maintaining hPSC self-renewal. Also, since naïve pluripotency has been widely recognized as an alternative pluripotent state of hPSCs, we discuss the possible effects of culture substrates and integrin signaling on naïve hPSCs based on the studies of mouse embryonic stem cells. Understanding the role of culture substrates in hPSC self-renewal and differentiation enables us to control hPSC behavior precisely and to establish scalable or microfabricated culture technologies for regenerative medicine and drug development.

  4. Zeta potential of microfluidic substrates: 2. Data for polymers.

    Science.gov (United States)

    Kirby, Brian J; Hasselbrink, Ernest F

    2004-01-01

    Zeta potential data are reviewed for a variety of polymeric microfluidic substrate materials. Many of these materials currently used for microchip fabrication have only recently been employed for generation of electroosmotic flow. Despite their recent history, polymeric microfluidic substrates are currently used extensively for microchip separations and other techniques, and understanding of the surface zeta potential is crucial for experimental design. This paper proposes the use of pC (the negative logarithm of the counterion concentration) as a useful normalization for the zeta potential on polymer substrates in contact with indifferent univalent counterions. Normalizing zeta by pC facilitates comparison of results from many investigators. The sparseness of available data for polymeric substrates prevents complete and rigorous justification for this normalization; however, it is consistent with double layer and adsorption theory. For buffers with indifferent univalent cations, normalization with the logarithm of the counterion concentration in general collapses data onto a single zeta/pC vs. pH curve, and (with the exception of PMMA) the repeatability of the data is quite encouraging. Normalization techniques should allow improved ability to predict zeta potential performance on microfluidic substrates and compare results observed with different parameters.

  5. Computational Approach for Epitaxial Polymorph Stabilization through Substrate Selection

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Hong; Dwaraknath, Shyam S.; Garten, Lauren; Ndione, Paul; Ginley, David; Persson, Kristin A.

    2016-05-25

    With the ultimate goal of finding new polymorphs through targeted synthesis conditions and techniques, we outline a computational framework to select optimal substrates for epitaxial growth using first principle calculations of formation energies, elastic strain energy, and topological information. To demonstrate the approach, we study the stabilization of metastable VO2 compounds which provides a rich chemical and structural polymorph space. We find that common polymorph statistics, lattice matching, and energy above hull considerations recommends homostructural growth on TiO2 substrates, where the VO2 brookite phase would be preferentially grown on the a-c TiO2 brookite plane while the columbite and anatase structures favor the a-b plane on the respective TiO2 phases. Overall, we find that a model which incorporates a geometric unit cell area matching between the substrate and the target film as well as the resulting strain energy density of the film provide qualitative agreement with experimental observations for the heterostructural growth of known VO2 polymorphs: rutile, A and B phases. The minimal interfacial geometry matching and estimated strain energy criteria provide several suggestions for substrates and substrate-film orientations for the heterostructural growth of the hitherto hypothetical anatase, brookite, and columbite polymorphs. These criteria serve as a preliminary guidance for the experimental efforts stabilizing new materials and/or polymorphs through epitaxy. The current screening algorithm is being integrated within the Materials Project online framework and data and hence publicly available.

  6. Study of water infiltration in a lightweight green roof substrate

    Science.gov (United States)

    Tomankova, Klara; Holeckova, Martina; Jelinkova, Vladimira; Snehota, Michal

    2015-04-01

    Green roofs have a positive impact on the environment (e.g. improving microclimate and air quality in cities, reducing solar absorbance and storm water). A laboratory infiltration experiment was conducted on the narrow flume serving as 2D vertical model of a green roof. The lightweight Optigreen substrate Type M was used (depth of 20 cm). The front wall of the flume was transparent and inspected by digital camera. The experiment was designed to measure pressure head, volumetric water content and calculate water retention in the substrate. Experiment comprised three artificial rainfall intensities with different values of initial water content of the substrate. The experimental results confirmed that green roofs have the ability to retain rainwater and thus have a beneficial effect on reducing runoff. In the experiment with the artificial 10 minutes rainfall event (total precipitation of 29 mm), the air dry substrate retained 95.9 % of precipitation. On the other hand for moist initial condition 4.2 % of precipitations amount was captured in the substrate. Additionally, the analysis of images taken during the experiment confirmed preferential flow and uneven advancement of the wetting front. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech Science Foundation under project number 14-10455P.

  7. Modeling of the Substrate Influence on Multielement THz Detector Operation

    Science.gov (United States)

    Sakhno, M.; Gumenjuk-Sichevska, J.; Sizov, F.

    2014-09-01

    The development of THz multielement uncooled imagers based on focal plane arrays (FPAs) requires an optimization of the system parameters to achieve a homogeneous sensitivity of the array elements. Results of numerical simulation of the eight-element linear array of planar antennas with detecting elements, on a substrate of finite dimensions are presented. We establish how the substrate thickness h and the relative permittivity ɛ r influence antenna pattern and antenna-detector matching for each element. We show that the antenna pattern depends on the detector position more than the antenna - detector impedance matching. The gain of array elements, the antenna-detector matching, and the homogeneity of the detector sensitivity can be simultaneously optimized by the proper choice of the substrate thickness h and the relative permittivity ɛ r . We show that multielement systems with large substrate thickness and high relative permittivity are not suitable for the imaging system implementation. To achieve uniform multielement system sensitivity, substrates with low permittivity ( ɛ r corruption.

  8. Weather resistance of inkjet prints on plastic substrates

    Directory of Open Access Journals (Sweden)

    Rozália Szentgyörgyvölgyi

    2015-06-01

    Full Text Available The development of wide format inkjet printers made the technology available for large area commercials. Outdoor advertising uses a wide range of substrate including paperboard, vinyl, canvas, mesh; the material of the substrate itself has to endure the physical and chemical effects of local weather. Weather elements (humidity, wind, solar irradiation degrade printed products inevitably; plastic products have better resistance against them, than paper based substrates. Service life of the printed product for outdoor application is a key parameter from the customer’s point of view. There are two ways to estimate expected lifetime: on site outdoor testing or laboratory testing. In both cases weathering parameters can be monitored, however laboratory testing devices may produce the desired environmental effects and thus accelerate the aging process. Our research objective was to evaluate the effects of artificial weathering on prints produced by inkjet technology on plastic substrates. We used a large format CMYK inkjet printer (Mutoh Rockhopper II, with Epson DX 4 print heads to print our test chart on two similar substrates (PVC coated tarpaulins with grammages 400 g/m2 and 440 g/m2. Specimen were aged in an Atlas Suntest XLS+ material tester device for equal time intervals. We measured and calculated the gradual changes of the optical properties (optical density, tone value, colour shifts of the test prints.

  9. Design and optimization of cantilevered magnetostrictive film-substrate microactuator

    Institute of Scientific and Technical Information of China (English)

    B.; Narsu; YUN; GuoHong; RONG; JianHong

    2007-01-01

    The exact solution for the bending problem of a free-end point loaded films-ubstrate cantilever with arbitrary film-to-substrate thickness ratio is obtained by using the basic mechanical equilibrium equation. And then the problem of design and optimization for microactuator buildup of film-substrate cantilever is discussed by taking into account the effect of geometrical and physical parameters of the cantilever components. Furthermore, the optimal condition for actuator application is presented and some theoretical problems are clarified. The results show that, in general, the greater the film-to-substrate thickness ratio, the higher the ability of taking load, namely the larger the exerted force of the cantilever when the thickness of substrate is kept constant. When the total thickness of the cantilever is kept constant, however, the free-end exerted force will experience a maximum and this maximum value of the exerted force will decrease with the increasing film-to-sub- strate stiffness ratio. Meanwhile, the optimal thickness ratio corresponding to this maximum exerted force also decreases with the increasing stiffness ratio. Whether for the cases of fixed substrate or fixed total thickness, the influence of Poisson's ratio of two cantilever components on the exerted force is remarkable, and should not be neglected.

  10. Molecular docking simulations provide insights in the substrate binding sites and possible substrates of the ABCC6 transporter.

    Directory of Open Access Journals (Sweden)

    Mohammad Jakir Hosen

    Full Text Available The human ATP-binding cassette family C member 6 (ABCC6 gene encodes an ABC transporter protein (ABCC6, primarily expressed in liver and kidney. Mutations in the ABCC6 gene cause pseudoxanthoma elasticum (PXE, an autosomal recessive connective tissue disease characterized by ectopic mineralization of the elastic fibers. The pathophysiology underlying PXE is incompletely understood, which can at least partly be explained by the undetermined nature of the ABCC6 substrates as well as the unknown substrate recognition and binding sites. Several compounds, including anionic glutathione conjugates (N-ethylmaleimide; NEM-GS and leukotriene C4 (LTC4 were shown to be modestly transported in vitro; conversely, vitamin K3 (VK3 was demonstrated not to be transported by ABCC6. To predict the possible substrate binding pockets of the ABCC6 transporter, we generated a 3D homology model of ABCC6 in both open and closed conformation, qualified for molecular docking and virtual screening approaches. By docking 10 reported in vitro substrates in our ABCC6 3D homology models, we were able to predict the substrate binding residues of ABCC6. Further, virtual screening of 4651 metabolites from the Human Serum Metabolome Database against our open conformation model disclosed possible substrates for ABCC6, which are mostly lipid and biliary secretion compounds, some of which are found to be involved in mineralization. Docking of these possible substrates in the closed conformation model also showed high affinity. Virtual screening expands this possibility to explore more compounds that can interact with ABCC6, and may aid in understanding the mechanisms leading to PXE.

  11. Separating semiconductor devices from substrate by etching graded composition release layer disposed between semiconductor devices and substrate including forming protuberances that reduce stiction

    Science.gov (United States)

    Tauke-Pedretti, Anna; Nielson, Gregory N; Cederberg, Jeffrey G; Cruz-Campa, Jose Luis

    2015-05-12

    A method includes etching a release layer that is coupled between a plurality of semiconductor devices and a substrate with an etch. The etching includes etching the release layer between the semiconductor devices and the substrate until the semiconductor devices are at least substantially released from the substrate. The etching also includes etching a protuberance in the release layer between each of the semiconductor devices and the substrate. The etch is stopped while the protuberances remain between each of the semiconductor devices and the substrate. The method also includes separating the semiconductor devices from the substrate. Other methods and apparatus are also disclosed.

  12. Evaluation of different substrates for inkjet printing of rasagiline mesylate

    DEFF Research Database (Denmark)

    Genina, Natalja; Janßen, Eva Maria; Breitenbach, Armin;

    2013-01-01

    ) was used as a low-dose active pharmaceutical ingredient (API). Flexible doses of the drug in a single unit were obtained by printing several subsequent layers on top of the already printed ones, using an off-the-shelf consumer thermal inkjet (TIJ) printer. The produced drug-delivery systems were subjected...... paper due to absorption of the ink into the matrix of the substrate. The best linear correlation between the dose of the drug and the number of the printing layers was obtained for the porous copy paper. The other two substrates showed poor linearity and unacceptable standard deviations of the printed...... drug substance due to limited absorption of the API ink into the carrier. The shear stress between the substrate, the print head, and the paper feeding rollers caused smearing of the drug that had been surface-deposited during the earlier printing cycles. In conclusion, this study indicates...

  13. Graphene nanoribbons anchored to SiC substrates

    Science.gov (United States)

    Le, Nam B.; Woods, Lilia M.

    2016-09-01

    Graphene nanoribbons are quasi-one-dimensional planar graphene allotropes with diverse properties dependent on their width and types of edges. Graphene nanoribbons anchored to substrates is a hybrid system, which offers novel opportunities for property modifications as well as experimental control. Here we present electronic structure calculations of zigzag graphene nanoribbons chemically attached via the edges to the Si or C terminated surfaces of a SiC substrate. The results show that the edge characteristics are rather robust and the properties are essentially determined by the individual nanoribbon. While the localized spin polarization of the graphene nanoribbon edge atoms is not significantly affected by the substrate, secondary energy gaps in the highest conduction and lowest valence region may emerge in the anchored structures. The van der Waals interaction together with the electrostatic interactions due to the polarity of the surface bonds are found to be important for the structure parameters and energy stability.

  14. Mechanically flexible optically transparent porous mono-crystalline silicon substrate

    KAUST Repository

    Rojas, Jhonathan Prieto

    2012-01-01

    For the first time, we present a simple process to fabricate a thin (≥5μm), mechanically flexible, optically transparent, porous mono-crystalline silicon substrate. Relying only on reactive ion etching steps, we are able to controllably peel off a thin layer of the original substrate. This scheme is cost favorable as it uses a low-cost silicon <100> wafer and furthermore it has the potential for recycling the remaining part of the wafer that otherwise would be lost and wasted during conventional back-grinding process. Due to its porosity, it shows see-through transparency and potential for flexible membrane applications, neural probing and such. Our process can offer flexible, transparent silicon from post high-thermal budget processed device wafer to retain the high performance electronics on flexible substrates. © 2012 IEEE.

  15. Fourier optics for polymeric substrates and coating textures analysis

    CERN Document Server

    Sparavigna, Amelia

    2008-01-01

    Several devices for substrate texture detection based on diffractive optics, for paper, textiles and non-wovens have been proposed in the past for direct inspection during the production processes. In spite of the presence of devices totally based on image processing, the use of diffractive optics cannot be considered surpassed for many reasons. Compared with image processing procedures, it is less sensitive to vibrations and does not suffer from the presence of ambient light. Based on transmitted light, it can give information on changes in refractive indexes, thickness variation and surface conditions. We study the use of optical Fourier spectrum to identify textures of polymer films. As the power spectrum reveals, the texture is seldom homogeneous. Here we report investigation on several substrates and on thin ink coatings on substrate. Role of bulk and surface conditions is analysed.

  16. Flexible and tunable silicon photonic circuits on plastic substrates

    CERN Document Server

    Chen, Yu; Li, Mo

    2012-01-01

    Flexible microelectronics has shown tremendous promise in a broad spectrum of applications, especially those that cannot be addressed by conventional microelectronics in rigid materials and constructions1-3. These unconventional yet important applications range from flexible consumer electronics to conformal sensor arrays and biomedical devices. A recent successful paradigm shift in implementing flexible electronics is to physically transfer and bond highly integrated devices made in high-quality, crystalline semiconductor materials on to plastic materials4-8. Here we demonstrate a flexible form of silicon photonics on plastic substrates using the transfer-and-bond fabrication method. Photonic circuits including interferometers and resonators have been transferred onto flexible plastic substrates with preserved functionalities and performance. By mechanically deforming the flexible substrates, the optical characteristics of the devices can be tuned reversibly over a remarkably large range. The demonstration o...

  17. Substrate specificity within a family of outer membrane carboxylate channels.

    Directory of Open Access Journals (Sweden)

    Elif Eren

    2012-01-01

    Full Text Available Many Gram-negative bacteria, including human pathogens such as Pseudomonas aeruginosa, do not have large-channel porins. This results in an outer membrane (OM that is highly impermeable to small polar molecules, making the bacteria intrinsically resistant towards many antibiotics. In such microorganisms, the majority of small molecules are taken up by members of the OprD outer membrane protein family. Here we show that OprD channels require a carboxyl group in the substrate for efficient transport, and based on this we have renamed the family Occ, for outer membrane carboxylate channels. We further show that Occ channels can be divided into two subfamilies, based on their very different substrate specificities. Our results rationalize how certain bacteria can efficiently take up a variety of substrates under nutrient-poor conditions without compromising membrane permeability. In addition, they explain how channel inactivation in response to antibiotics can cause resistance but does not lead to decreased fitness.

  18. Dynamic buckling behavior of thin metal film lines from substrate

    Science.gov (United States)

    Wu, Dan; Xie, Huimin; Wang, Heling; Zhang, Jie; Li, Chuanwei

    2014-10-01

    The dynamic buckling behavior of thin films from substrate is studied in this work. The experimental results show that the buckling morphology of the constantan film lines from the polymer substrate is inconsistent and non-sinusoidal, which is different from the sinusoidal form of the buckling morphology under static loads. The plastic deformation of the film lines results in the non-sinusoidal buckling morphology and residual deformation when unloaded. Finite element modeling results with regard to the plastic dissipation of the constantan film lines reveal that the plastic dissipation suppresses the buckling-driven delaminating under impact loads. This study will give some new perspectives on the buckling behavior of thin film from substrate.

  19. Microstructured apertures in planar glass substrates for ion channel research.

    Science.gov (United States)

    Fertig, Niels; George, Michael; Klau, Michèle; Meyer, Christine; Tilke, Armin; Sobotta, Constanze; Blick, Robert H; Behrends, Jan C

    2003-01-01

    We have developed planar glass chip devices for patch clamp recording. Glass has several key advantages as a substrate for planar patch clamp devices. It is a good dielectric, is well-known to interact strongly with cell membranes and is also a relatively in-expensive material. In addition, it is optically neutral. However, microstructuring processes for glass are less well established than those for silicon-based substrates. We have used ion-track etching techniques to produce micron-sized apertures into borosilicate and quartz-glass coverslips. These apertures, which can be easily produced in arrays, have been used for high resolution recording of single ion channels as well as for whole-cell current recordings from mammalian cell lines. An additional attractive application that is greatly facilitated by the combination of planar geometry with the optical neutrality of the substrate is single-molecule fluorescence recording with simultaneous single-channel measurements.

  20. Aligned Silver Nanorod Array as SERS Substrates for Viral Sensing

    Science.gov (United States)

    Zhao, Yiping; Shanmukh, Saratchandra; Chaney, Stephen B.; Jones, Les; Dluhy, Richard A.; Tripp, Ralph A.

    2006-03-01

    The aligned silver nanorod array substrates prepared by the oblique angle deposition method are capable of providing extremely high enhancement factors (˜10^9) at near-infrared wavelengths (785 nm) for a standard reporter molecule 1,2 trans-(bis)pyridyl-ethene (BPE). The enhancement factor depends strongly on the length of the Ag nanorods, the substrate coating, as well as the polarization of the excitation laser beam. With the current optimum structure, we demonstrate that the detection limit for BPE can be lower than 0.1 fM. The applicability of this substrate to the detection of bioagents has been investigated by looking several viruses, such as Adenovirus, HIV, Rhinovirus and Respiratory Syncytial Virus (RSV), at low quantities (˜0.5uL). Different viruses have different fingerprint Raman spectrum. The detection of virus presented in infected cells has also been demonstrated.

  1. Substrate and drug binding sites in LeuT.

    Science.gov (United States)

    Nyola, Ajeeta; Karpowich, Nathan K; Zhen, Juan; Marden, Jennifer; Reith, Maarten E; Wang, Da-Neng

    2010-08-01

    LeuT is a member of the neurotransmitter/sodium symporter family, which includes the neuronal transporters for serotonin, norepinephrine, and dopamine. The original crystal structure of LeuT shows a primary leucine-binding site at the center of the protein. LeuT is inhibited by different classes of antidepressants that act as potent inhibitors of the serotonin transporter. The newly determined crystal structures of LeuT-antidepressant complexes provide opportunities to probe drug binding in the serotonin transporter, of which the exact position remains controversial. Structure of a LeuT-tryptophan complex shows an overlapping binding site with the primary substrate site. A secondary substrate binding site was recently identified, where the binding of a leucine triggers the cytoplasmic release of the primary substrate. This two binding site model presents opportunities for a better understanding of drug binding and the mechanism of inhibition for mammalian transporters.

  2. Low dielectric polyimide aerogels as substrates for lightweight patch antennas.

    Science.gov (United States)

    Meador, Mary Ann B; Wright, Sarah; Sandberg, Anna; Nguyen, Baochau N; Van Keuls, Frederick W; Mueller, Carl H; Rodríguez-Solís, Rafael; Miranda, Félix A

    2012-11-01

    The dielectric properties and loss tangents of low-density polyimide aerogels have been characterized at various frequencies. Relative dielectric constants as low as 1.16 were measured for polyimide aerogels made from 2,2'-dimethylbenzidine (DMBZ) and biphenyl 3,3',4,4'-tetracarbozylic dianhydride (BPDA) cross-linked with 1,3,5-triaminophenoxybenzene (TAB). This formulation was used as the substrate to fabricate and test prototype microstrip patch antennas and benchmark against state of practice commercial antenna substrates. The polyimide aerogel antennas exhibited broader bandwidth, higher gain, and lower mass than the antennas made using commercial substrates. These are very encouraging results, which support the potential advantages of the polyimide aerogel-based antennas for aerospace applications.

  3. Evaluation of SERS substrates for chemical agent detection

    Science.gov (United States)

    Huang, Hermes; Shende, Chetan; Sengupta, Atanu; Inscore, Frank; Farquharson, Stuart

    2012-06-01

    US Military forces are dependent on indigenous water supplies, which are considered prime targets to effect a chemical or biological attack. Consequently, there is a clear need for a portable analyzer capable of evaluating water supplies prior to use. To this end we have been investigating the use of a portable Raman analyzer with surface-enhanced Raman spectroscopy (SERS) sampling systems. The superior selectivity and exceptional sensitivity of SERS has been demonstrated by the detection of single molecules. However, the extreme sensitivity provided by SERS is attributed to "hot spot" structures, such as particle junctions that can provide as much as 10 orders of magnitude enhancement. Unfortunately, hotspots are not evenly distributed across substrates, which results in enhancements that cannot be quantitatively reproduced. Here we present analysis of uniformity for a newly developed substrate and commercial sample vials using benzenethiol and bispyridylethylene, two chemicals often used to characterize SERS substrates, and methyl phosphonic acid, a major hydrolysis product of the nerve agents.

  4. Effect of different substrates on Compact stacked square Microstrip Antenna

    CERN Document Server

    De, Asok; Malhotra, Sagar; Arora, Pushkar; Bazaz, Rishik

    2010-01-01

    Selection of the most suitable substrate for a Microstrip antenna is a matter of prime importance. This is because many limitations of the microstrip antenna such as high return loss, low gain and low efficiency can be overcome by selecting an appropriate substrate for fabrication of the antenna, without shifting the resonant frequency significantly. The substate properties such as its dielectric constant, loss tangent have a pronounced effect on the antenna characteristics. Some of the critical properties that are to be taken care of while selecting a dielectric are homogeneity, moisture absorption and adhesion of metal- foil cladding. In this paper a comprehensive study of the effect of variation of substrate material on the antenna properties has been presented.

  5. Liquid 4He Adsorbed Films on Very Attractive Substrates

    Science.gov (United States)

    Urrutia, Ignacio; Szybisz, Leszek

    Adsorbed films of liquid 4He are analized, in the framework of Density Functional Theories (DF). In these systems, when the substrate becomes increasingly attractive, the thin films of 4He approaches the quasi-bidimensional limit. We study this strongly attractive substrate regime with two DF, the Orsay-Trento (OT) and a recent Hybrid proposal (Hyb), focusing in the energy behavior. It is showed that OT does not reproduce the correct limiting energy curve, and it implies that this functional could not provide reliable results for very strongly attractive substrates like Graphite (Gr). In other hand, with the Hyb DF, the correct energy behavior is found for the adsorption energy of 4He on Gr. These results show that OT should not be applied to quasi 2D (confinement) situations, and that Hyb DF provides a much more realistic description.

  6. Liquid 4He Adsorbed Films on Very Attractive Substrates

    Science.gov (United States)

    Urrutia, Ignacio; Szybisz, Leszek

    2006-09-01

    Adsorbed films of liquid 4He are analized, in the framework of Density Functional Theories (DF). In these systems, when the substrate becomes increasingly attractive, the thin films of 4He approaches the quasi-bidimensional limit. We study this strongly attractive substrate regime with two DF, the Orsay-Trento (OT) and a recent Hybrid proposal (Hyb), focusing in the energy behavior. It is showed that OT does not reproduce the correct limiting energy curve, and it implies that this functional could not provide reliable results for very strongly attractive substrates like Graphite (Gr). In other hand, with the Hyb DF, the correct energy behavior is found for the adsorption energy of 4He on Gr. These results show that OT should not be applied to quasi 2D (confinement) situations, and that Hyb DF provides a much more realistic description.

  7. Elastic Analysis of Physisorption-Induced Substrate Deformation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-Qiao; PAN Xia-Hui; YU Shou-Wen; FENG Xi-Qiao

    2008-01-01

    Physisorption may cause a dimple on a deformable solid surface due to adsorbate-substrate interaction.The interactive force between the adsorbate and the crystal atoms depends on their distances,which may change with substrate deformation.This feature of displacement-dependence indicates that the equilibrium problem is a force-deformation coupled nonlinear procedure.In the present study,a continuum mechanics model,in which the force is considered as a function of the displacement field of the medium,is presented to calculate the physisorption-inducad deformation in a semi-infinite elastic medium.It is found that the nonlinear effect due to force-deformation coupling should be taken in consideration in the adsorbate-substrate interaction analysis.

  8. A simple procedure for preparing substrate for Pleurotus ostreatus cultivation.

    Science.gov (United States)

    Hernández, Daniel; Sánchez, José E; Yamasaki, Keiko

    2003-11-01

    The use of wooden crates for composting a mixture of 70% grass, (Digitaria decumbens), and 30% coffee pulp, combined with 2% Ca(OH)(2), was studied as a method for preparing substrate for the cultivation of Pleurotus ostreatus. Crate composting considerably modified the temperature pattern of the substrate in process, as compared to pile composting, where lower temperatures and less homogeneous distributions were observed. Biological efficiencies varied between 59.79% and 93% in the two harvests. Based on statistical analysis significant differences were observed between the treatments, composting times and in the interactions between these two factors. We concluded that it is possible to produce P. ostreatus on a lignocellulosic, non-composted, non-pasteurized substrate with an initial pH of 8.7, and that composting for two to three days improves the biological efficiency.

  9. Highly reflective polymeric substrates functionalized utilizing atomic layer deposition

    Science.gov (United States)

    Zuzuarregui, Ana; Coto, Borja; Rodríguez, Jorge; Gregorczyk, Keith E.; Ruiz de Gopegui, Unai; Barriga, Javier; Knez, Mato

    2015-08-01

    Reflective surfaces are one of the key elements of solar plants to concentrate energy in the receivers of solar thermal electricity plants. Polymeric substrates are being considered as an alternative to the widely used glass mirrors due to their intrinsic and processing advantages, but optimizing both the reflectance and the physical stability of polymeric mirrors still poses technological difficulties. In this work, polymeric surfaces have been functionalized with ceramic thin-films by atomic layer deposition. The characterization and optimization of the parameters involved in the process resulted in surfaces with a reflection index of 97%, turning polymers into a real alternative to glass substrates. The solution we present here can be easily applied in further technological areas where seemingly incompatible combinations of polymeric substrates and ceramic coatings occur.

  10. Low profile conformal antenna arrays on high impedance substrate

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2016-01-01

    This book presents electromagnetic (EM) design and analysis of dipole antenna array over high impedance substrate (HIS). HIS is a preferred substrate for low-profile antenna design, owing to its unique boundary conditions. Such substrates permit radiating elements to be printed on them without any disturbance in the radiation characteristics. Moreover HIS provides improved impedance matching, enhanced bandwidth, and increased broadside directivity owing to total reflection from the reactive surface and high input impedance. This book considers different configurations of HIS for array design on planar and non-planar high-impedance surfaces. Results are presented for cylindrical dipole, printed dipole, and folded dipole over single- and double-layered square-patch-based HIS and dogbone-based HIS. The performance of antenna arrays is analyzed in terms of performance parameters such as return loss and radiation pattern. The design presented shows acceptable return loss and mainlobe gain of radiation pattern. Thi...

  11. Optically transparent frequency selective surfaces on flexible thin plastic substrates

    Science.gov (United States)

    Dewani, Aliya A.; O'Keefe, Steven G.; Thiel, David V.; Galehdar, Amir

    2015-02-01

    A novel 2D simple low cost frequency selective surface was screen printed on thin (0.21 mm), flexible transparent plastic substrate (relative permittivity 3.2). It was designed, fabricated and tested in the frequency range 10-20 GHz. The plane wave transmission and reflection coefficients agreed with numerical modelling. The effective permittivity and thickness of the backing sheet has a significant effect on the frequency characteristics. The stop band frequency reduced from 15GHz (no backing) to 12.5GHz with polycarbonate. The plastic substrate thickness beyond 1.8mm has minimal effect on the resonant frequency. While the inner element spacing controls the stop-band frequency, the substrate thickness controls the bandwidth. The screen printing technique provided a simple, low cost FSS fabrication method to produce flexible, conformal, optically transparent and bio-degradable FSS structures which can find their use in electromagnetic shielding and filtering applications in radomes, reflector antennas, beam splitters and polarizers.

  12. Crystal Structure and Substrate Specificity of PTPN12

    Directory of Open Access Journals (Sweden)

    Hui Li

    2016-05-01

    Full Text Available PTPN12 is an important tumor suppressor that plays critical roles in various physiological processes. However, the molecular basis underlying the substrate specificity of PTPN12 remains uncertain. Here, enzymological and crystallographic studies have enabled us to identify two distinct structural features that are crucial determinants of PTPN12 substrate specificity: the pY+1 site binding pocket and specific basic charged residues along its surface loops. Key structurally plastic regions and specific residues in PTPN12 enabled recognition of different HER2 phosphorylation sites and regulated specific PTPN12 functions. In addition, the structure of PTPN12 revealed a CDK2 phosphorylation site in a specific PTPN12 loop. Taken together, our results not only provide the working mechanisms of PTPN12 for desphosphorylation of its substrates but will also help in designing specific inhibitors of PTPN12.

  13. Adsorption of Helium Atoms on Two-Dimensional Substrates

    Science.gov (United States)

    Burganova, Regina; Lysogorskiy, Yury; Nedopekin, Oleg; Tayurskii, Dmitrii

    2016-12-01

    The study of the adsorption phenomenon of helium began many decades ago with the discovery of graphite as a homogeneous substrate for the investigation of physically adsorbed monolayer films. In particular, helium monoatomic layers on graphite were found to exhibit a very rich phase diagram. In the present work we have investigated the adsorption phenomenon of helium atoms on graphene and silicene substrates by means of density functional theory with Born-Oppenheimer approximation. Helium-substrate and helium-helium interactions were considered from first principles. Vibrational properties of adsorbed monolayers have been used to explore the stability of the system. This approach reproduces results describing the stability of a helium monolayer on graphene calculated by quantum Monte Carlo (QMC) simulations for low and high coverage cases. However, for the moderate coverage value there is a discrepancy with QMC results due to the lack of helium zero point motion.

  14. Proposed cryogenic Q-factor measurement of mirror substrates

    Energy Technology Data Exchange (ETDEWEB)

    Nietzsche, Sandor; Zimmer, Anja; Vodel, Wolfgang; Thuerk, Matthias; Schmidl, Frank; Seidel, Paul [Institut fuer Festkoerperphysik, Friedrich-Schiller-Universitaet Jena, Helmholtzweg 5, 07743 Jena (Germany)

    2004-03-07

    The thermal noise of optical components (e.g., end mirrors, beam splitters) is one of the limiting factors of the sensitivity of most of the present interferometric gravitational wave detectors, and it will be limiting in the advanced detectors now being designed. This thermal noise occurs mainly in the optical substrates and their mirror coatings. One possible method for minimizing thermal noise is cooling to cryogenic temperatures, maximizing the mechanical Q and maximizing the eigenfrequencies of the substrate. A new cryogenic apparatus for investigations of the temperature dependency of the Q-factor of several substrate materials down to 4.2 K is proposed. Possible methods of mode excitation and ring down measurement are discussed.

  15. Substrate Recognition of Histone H2B by DUBm

    Science.gov (United States)

    Henderson, Elizabeth; Berndsen, Christopher; Wolberger, Cynthia

    2011-03-01

    The SAGA complex is a transcriptional coactivator that regulates gene expression in eukaryotes via histone acetylation and deubiquitination, which are crucial for transcription. Our lab is investigating the SAGA-dependent deubiquitination of histone H2B. The deubiquitinating module (DUBm) of SAGA is comprised of a ubiquitin-specific protease, Ubp8, and three other proteins. It is known that Ubp8 cleaves ubiquitin from histone H2B, however, the specific way in which the enzyme binds to the substrate remains elusive. In order to unravel this mechanism, we attempted to determine the crystal structure of the substrate binding complex. We obtained this substrate by exploiting the techniques of intein chemistry to artificially ubiquitinate a histone H2B peptide, which we then co-crystallized with DUBm. Additionally, we synthesized Ub-K63R-linked chains and Ub-K48-linked chains and co-crystallized them with DUBm.

  16. Ion beam mixing of titanium overlayers with hydroxyapaptite substrates

    Energy Technology Data Exchange (ETDEWEB)

    Levine, T.E. [Cornell Univ., Ithaca, NY (United States). Dept. of Materials Science and Engineering; Nastasi, M. [Los Alamos National Lab., NM (United States); Alford, T.L.; Suchicital, C.; Russell, S.; Luptak, K.; Pizziconi, V.; Mayer, J.W. [Arizona State Univ., Tempe, AZ (United States)

    1995-01-01

    The mixing of titanium overlayers with hydroxyapatite (HA) substrates via ion irradiation has been demonstrated. Analysis via secondary ion mass spectroscopy (SIMS) indicates an interfacial broadening of titanium and calcium of the implanted sample compared to that of the unimplanted sample. Attendant to the observed ion beam mixing of titanium into the HA, the oxygen signal of the titanium overlayer increases as a result of ion irradiation. It is supposed that this change is evident of diffusion through the metal layer and possibly from titania formation at the free surface and perovskite formation at the film/substrate interface. This possibility is consistent with thermodynamic predictions. Additionally, the force required to separate the film from the substrate increased as a result of ion irradiation, validating the continued study of ion beam processing of Ti/HA systems towards the improvement of long term fixation of implant devices.

  17. Highly reflective polymeric substrates functionalized utilizing atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Zuzuarregui, Ana, E-mail: a.zuzuarregui@nanogune.eu; Gregorczyk, Keith E. [CIC Nanogune Consolider, de Tolosa Hiribidea 76, 20018 San Sebastián (Spain); Coto, Borja; Ruiz de Gopegui, Unai; Barriga, Javier [IK4-Tekniker, Iñaki Goenaga 5, 20600 Eibar (Spain); Rodríguez, Jorge [Torresol Energy (SENER Group), Avda. de Zugazarte 61, 48930 Las Arenas (Spain); Knez, Mato [CIC Nanogune Consolider, de Tolosa Hiribidea 76, 20018 San Sebastián (Spain); IKERBASQUE Basque Foundation for Science, Maria Diaz de Haro 3, 48013 Bilbao (Spain)

    2015-08-10

    Reflective surfaces are one of the key elements of solar plants to concentrate energy in the receivers of solar thermal electricity plants. Polymeric substrates are being considered as an alternative to the widely used glass mirrors due to their intrinsic and processing advantages, but optimizing both the reflectance and the physical stability of polymeric mirrors still poses technological difficulties. In this work, polymeric surfaces have been functionalized with ceramic thin-films by atomic layer deposition. The characterization and optimization of the parameters involved in the process resulted in surfaces with a reflection index of 97%, turning polymers into a real alternative to glass substrates. The solution we present here can be easily applied in further technological areas where seemingly incompatible combinations of polymeric substrates and ceramic coatings occur.

  18. Process for forming a metal compound coating on a substrate

    Science.gov (United States)

    Sharp, D.J.; Vernon, M.E.; Wright, S.A.

    1988-06-29

    A method of coating a substrate with a thin layer of a metal compound by forming a dispersion of an electrophoretically active organic colloid and a precursor of the metal compound in an electrolytic cell in which the substrate is an electrode. Upon application of an electric potential, the electrode is coated with a mixture of the organic colloid and the precursor to the metal compound, and the coated substrate is then heated in the presence of an atmosphere or vacuum to decompose the organic colloid and form a coating of either a combination of metal compound and carbon, or optionally forming a porous metal compound coating by heating to a temperature high enough to chemically react the carbon.

  19. System and method for floating-substrate passive voltage contrast

    Science.gov (United States)

    Jenkins, Mark W.; Cole, Jr., Edward I.; Tangyunyong, Paiboon; Soden, Jerry M.; Walraven, Jeremy A.; Pimentel, Alejandro A.

    2009-04-28

    A passive voltage contrast (PVC) system and method are disclosed for analyzing ICs to locate defects and failure mechanisms. During analysis a device side of a semiconductor die containing the IC is maintained in an electrically-floating condition without any ground electrical connection while a charged particle beam is scanned over the device side. Secondary particle emission from the device side of the IC is detected to form an image of device features, including electrical vias connected to transistor gates or to other structures in the IC. A difference in image contrast allows the defects or failure mechanisms be pinpointed. Varying the scan rate can, in some instances, produce an image reversal to facilitate precisely locating the defects or failure mechanisms in the IC. The system and method are useful for failure analysis of ICs formed on substrates (e.g. bulk semiconductor substrates and SOI substrates) and other types of structures.

  20. Surprisingly high substrate specificities observed in complex biofilms

    DEFF Research Database (Denmark)

    Nierychlo, Marta; Kindaichi, Tomonori; Kragelund, Caroline;

    The behavior of microorganisms in natural ecosystems (e.g. biofilms) differs significantly from laboratory studies. In nature microorganisms experience alternating periods of surplus nutrients, nutrient-limitation, and starvation. Literature data suggests that to survive and compete successfully......, microorganisms can regulate their metabolism expressing wide range of uptake and catabolic systems. However, ecophysiological studies of natural biofilms indicate that bacteria are very specialized in their choice of substrate, so even minor changes in substrate composition can affect the community composition...... by selection for different specialized species. We hypothesized that bacteria growing in natural environment express strongly conserved substrate specificity which is independent on short-term (few hours) variations in growth conditions. In this study, biofilm from Aalborg wastewater treatment plant was used...

  1. Interactions between arbuscular mycorrhizal fungi and organic material substrates.

    Science.gov (United States)

    Hodge, Angela

    2014-01-01

    Arbuscular mycorrhizal (AM) associations are widespread and form between ca. two-thirds of all land plants and fungi in the phylum Glomeromycota. The association is a mutualistic symbiosis with the fungi enhancing nutrient capture for the plant while obtaining carbon in return. Although arbuscular mycorrhizal fungi (AMF) lack any substantial saprophytic capability they do preferentially associate with various organic substrates and respond by hyphal proliferation, indicating the fungus derives a benefit from the organic substrate. AMF may also enhance decomposition of the organic material. The benefit to the host plant of this hyphal proliferation is not always apparent, particularly regarding nitrogen (N) transfer, and there may be circumstances under which both symbionts compete for the N released given both have a large demand for N. The results of various studies examining AMF responses to organic substrates and the interactions with other members of the soil community will be discussed.

  2. Adsorption of Helium Atoms on Two-Dimensional Substrates

    Science.gov (United States)

    Burganova, Regina; Lysogorskiy, Yury; Nedopekin, Oleg; Tayurskii, Dmitrii

    2016-01-01

    The study of the adsorption phenomenon of helium began many decades ago with the discovery of graphite as a homogeneous substrate for the investigation of physically adsorbed monolayer films. In particular, helium monoatomic layers on graphite were found to exhibit a very rich phase diagram. In the present work we have investigated the adsorption phenomenon of helium atoms on graphene and silicene substrates by means of density functional theory with Born-Oppenheimer approximation. Helium-substrate and helium-helium interactions were considered from first principles. Vibrational properties of adsorbed monolayers have been used to explore the stability of the system. This approach reproduces results describing the stability of a helium monolayer on graphene calculated by quantum Monte Carlo (QMC) simulations for low and high coverage cases. However, for the moderate coverage value there is a discrepancy with QMC results due to the lack of helium zero point motion.

  3. Optically transparent frequency selective surfaces on flexible thin plastic substrates

    Energy Technology Data Exchange (ETDEWEB)

    Dewani, Aliya A., E-mail: a.ashraf@griffith.edu.au; O’Keefe, Steven G.; Thiel, David V.; Galehdar, Amir [School Of Electrical Engineering, Griffith University, Brisbane, 4111 (Australia)

    2015-02-15

    A novel 2D simple low cost frequency selective surface was screen printed on thin (0.21 mm), flexible transparent plastic substrate (relative permittivity 3.2). It was designed, fabricated and tested in the frequency range 10-20 GHz. The plane wave transmission and reflection coefficients agreed with numerical modelling. The effective permittivity and thickness of the backing sheet has a significant effect on the frequency characteristics. The stop band frequency reduced from 15GHz (no backing) to 12.5GHz with polycarbonate. The plastic substrate thickness beyond 1.8mm has minimal effect on the resonant frequency. While the inner element spacing controls the stop-band frequency, the substrate thickness controls the bandwidth. The screen printing technique provided a simple, low cost FSS fabrication method to produce flexible, conformal, optically transparent and bio-degradable FSS structures which can find their use in electromagnetic shielding and filtering applications in radomes, reflector antennas, beam splitters and polarizers.

  4. Strong adhesion in nanocrystalline diamond films on silicon substrates

    Science.gov (United States)

    Sharda, T.; Umeno, M.; Soga, T.; Jimbo, T.

    2001-05-01

    Strong adhesion is shown to be achieved in the growth of smooth nanocrystalline diamond (NCD) thin films on silicon substrates at 600 °C using biased enhanced growth in microwave plasma chemical vapor deposition. The strong adhesion is evident from the films sustaining compressive stress, which may be as high as 85 GPa. The substrates are bent spherically after deposition, however, films are not peeled off, in spite of having enormous in-plane stress. The strong adhesion may be a result of implanted carbon below the substrate surface with an optimized ion flux density in the initial stages of growth. The compressive stress in the films is shown to be generating from the graphitic and other nondiamond carbon impurities in the films. It was observed that the NCD grain size decreases with biasing hence increasing grain boundary area in the films accommodating more graphitic impurities, which in turn results in an increase in compressive stress in the films.

  5. Metabolic Engineering for Expanding the Substrate Range of Yarrowia lipolytica.

    Science.gov (United States)

    Ledesma-Amaro, Rodrigo; Nicaud, Jean-Marc

    2016-10-01

    Economically viable biotechnology processes must be characterized by a favorable ratio between the production costs and the product market price. In the bioproduction of bulk chemicals, costs must be minimized so that the process is competitive relative to petroleum-based production. The substrate costs must thus be reduced by employing inexpensive carbon sources, such as industrial wastes. Unfortunately, the most convenient microorganisms for a bioconversion are typically unable to degrade such substrates. Fortunately, the discovery of new enzymes together with advances in synthetic biology has moved metabolic engineering forward, expanding substrate ranges. Here we review the latest advances made using the industrial yeast Yarrowia lipolytica, which can exploit various carbon sources to produce biofuels and chemicals.

  6. [Biogas production from cellulose-containing substrates: a review].

    Science.gov (United States)

    Tsavkelova, E A; Netrusov, A I

    2012-01-01

    Anaerobic microbial conversion of organic substrates to various biofuels is one of the alternative energy sources attracting the greatest attention of scientists. The advantages of biogas production over other technologies are the ability of methanogenic communities to degrade a broad range of substrates and concomitant benefits: neutralization of organic waste, reduction of greenhouse gas emission, and fertilizer production. Cellulose-containing materials are a good substrate, but their full-scale utilization encounters a number of problems, including improvement of the quality and amount ofbiogas produced and maintenance of the stability and high efficiency of microbial communities. We review data on microorganisms that form methanogenic cellulolytic communities, enzyme complexes of anaerobes essential for cellulose fiber degradation, and feedstock pretreatment, as biodegradation is hindered in the presence of lignin. Methods for improving biogas production by optimization of microbial growth conditions are considered on the examples of biogas formation from various types of plant and paper materials: writing paper and cardboard.

  7. Substrate-induced reduction of graphene thermal conductivity

    Science.gov (United States)

    Koniakhin, S. V.; Utesov, O. I.; Terterov, I. N.; Nalitov, A. V.

    2017-01-01

    We develop a theory of heat conductivity in supported graphene, accounting for coherent phonon scattering on disorder induced by an amorphous substrate. We derive spectra for in-plane and out-of-plane phonons in the framework of Green's function approach. The energy parameters of the theory are obtained using molecular dynamics simulations for graphene on a SiO2 substrate. The heat conductivity is calculated by the Boltzmann transport equation. We find that the interaction with the substrate drastically reduces the phonon lifetime and completely suppresses the contribution of flexural (ZA) phonons to the heat conductivity. As a result, the total heat conductivity is reduced by several times, which matches with the tendency observed in the available experimental data. The considered effect is important for managing the thermal properties of graphene-based electronic devices.

  8. Performance of BTX degraders under substrate versatility conditions.

    Science.gov (United States)

    Maliyekkal, Shihabudeen M; Rene, Eldon R; Philip, Ligy; Swaminathan, T

    2004-06-18

    A microbial consortium acclimatized with benzene, toluene or xylene (BTX) was employed to study the degradation pattern of these compounds individually under aerobic conditions. Batch and continuous experiments were conducted to evaluate the adaptability of the enriched cultures under substrate versatility conditions. The bio-kinetic parameters obtained under substrate versatility conditions were compared with those of a single substrate condition. Similar degradation patterns were observed for all the substrates with inhibition occurring at higher concentration (approximately 150 mg/L for benzene and xylene, and approximately 200 mg/L for toluene). Toluene degradation was highest, followed by benzene and xylene in the aqueous phase. Adaptation to a more toxic compound like benzene and xylene improved the utilization of toluene. On the other hand, microbes grown on a less toxic compound (toluene) grew at a lower rate in the presence of more toxic compounds. Suitable kinetic parameters such as micro(max) (maximum specific growth rate per hour), Ks (half saturation constant, mg/L), and KI (threshold substrate inhibition constant, mg/L) were determined using Haldane and Levenspiel substrate inhibition models. The Haldane equation seems to be an adequate expression for the system. The degradation behavior of pollutants in the gas phase was also evaluated using a toluene acclimatized biotrickling filter operated in continuous mode. The biotrickling filter acclimatized with toluene could degrade benzene and xylene with a lower elimination capacity. But, the system could recover its original efficiency quite fast even after a prolonged shock loading. The degradation was better for toluene, followed by benzene and xylene.

  9. Composition of agarose substrate affects behavioral output of Drosophila larvae

    Directory of Open Access Journals (Sweden)

    Anthi Aristomenis Apostolopoulou

    2014-01-01

    Full Text Available In the last decade the Drosophila larva has evolved into a simple model organism offering the opportunity to integrate molecular genetics with systems neuroscience. This led to a detailed understanding of the functional neuronal networks for a number of sensory functions and behaviors including olfaction, vision, gustation and learning and memory. Typically, behavioral assays in use exploit simple Petri dish setups with either agarose or agar as a substrate. However, neither the quality nor the concentration of the substrate is generally standardized across these experiments and there is no data available on how larval behavior is affected by such different substrates. Here, we have investigated the effects of different agarose concentrations on several larval behaviors. We demonstrate that agarose concentration is an important parameter, which affects all behaviors tested: preference, feeding, learning and locomotion. Larvae can discriminate between different agarose concentrations, they feed differently on them, they can learn to associate an agarose concentration with an odor stimulus and crawl faster on a substrate of higher agarose concentration. Additionally, we have investigated the effect of agarose concentration on three quinine based behaviors: preference, feeding and learning. We show that in all cases examined the behavioral output changes in an agarose concentration-dependent manner. Our results suggest that comparisons between experiments performed on substrates differing in agarose concentration should be done with caution. It should be taken into consideration that the agarose concentration can affect the behavioral output and thereby the experimental outcomes per se potentially due to an increased escape response on more rigid substrates.

  10. Static and kinetic friction characteristics of nanowire on different substrates

    Science.gov (United States)

    Kim, Hyun-Joon; Nguyen, Gia Hau; Ky, Dinh Le Cao; Tran, Da Khoa; Jeon, Ki-Joon; Chung, Koo-Hyun

    2016-08-01

    Friction characteristics of nanowires (NWs), which may be used as building blocks for nano-devices, are crucial, especially for cases where contact sliding occurs during the device operation. In this work, the static and kinetic friction characteristics of oxidized Si NWs deposited on thermally grown SiO2 and chemical vapor-deposited single layer graphene were investigated using an atomic force microscope (AFM). Kinetic friction between the oxidized Si NWs and the substrates was directly measured by the AFM. Static friction was also obtained from the most bent state of the NWs using the individually determined elastic moduli of the NWs from kinetic friction experiments based on elastic beam theory. Furthermore, the shear stress between the oxidized Si NWs and the substrates was estimated based on adhesive contact theory. It was found that both static and kinetic friction increased as the radius of the NWs increased. The friction of the oxidized Si NWs on the graphene substrate was found to be smaller than that on the SiO2 substrate, which suggests that chemical vapor-deposited graphene can be used as a lubricant or as a protective layer in nano-devices to reduce friction. The shear stress estimated from the kinetic friction data between the oxidized Si NWs and the SiO2 substrate ranged from 7.5 to 12.3 MPa while that between the oxidized Si NWs and the graphene substrate ranged from 4.7 to 7.0 MPa. The result also indicated that the dependence of shear stress on the radius of the NWs was not significant. These findings may provide insight into the friction characteristics of NWs.

  11. Lignocellulolytic enzyme activity, substrate utilization, and mushroom yield by Pleurotus ostreatus cultivated on substrate containing anaerobic digester solids.

    Science.gov (United States)

    Isikhuemhen, Omoanghe S; Mikiashvilli, Nona A

    2009-11-01

    Solid waste from anaerobic digestion of litter from the commercial production of broiler chickens has limited use as fertilizer. Its disposal is a major problem for digester operators who are seeking alternative use for anaerobic digester solids, also referred to as solid waste (SW). The use of SW as substrates for the cultivation of Pleurotus ostreatus strain MBFBL400 was investigated. Lignocellulolytic enzymes activity, substrate utilization, and mushroom yield were evaluated in ten different substrate combinations (SCs) containing varying amounts of solid waste, wheat straw, and millet. Nutritional content of mushrooms produced on the different substrates was also determined. Substrates containing 70-80% wheat straw, 10-20% SW, and 10-20% millet were found to produce the highest mushroom yield (874.8-958.3 g/kg). Loss of organic matter in all SCs tested varied from 45.8% to 56.2%, which had positive correlation with the biological efficiency. Laccase, peroxidase, and carboxymethylcellulase (CMCase) activities were higher before fruiting, whereas xylanase showed higher activities after mushroom fruiting. SW increased the nutritional content in mushrooms harvested, and the combination of wheat straw and SW with millet significantly improved mushroom yield. Our findings demonstrated the possibility of utilizing anaerobic digester solids in mushroom cultivation. The application of SW as such could improve the financial gains in the overall economy of anaerobic digester plants.

  12. Seneca Valley Virus 3Cpro Substrate Optimization Yields Efficient Substrates for Use in Peptide-Prodrug Therapy.

    Directory of Open Access Journals (Sweden)

    Linde A Miles

    Full Text Available The oncolytic picornavirus Seneca Valley Virus (SVV-001 demonstrates anti-tumor activity in models of small cell lung cancer (SCLC, but may ultimately need to be combined with cytotoxic therapies to improve responses observed in patients. Combining SVV-001 virotherapy with a peptide prodrug activated by the viral protease 3Cpro is a novel strategy that may increase the therapeutic potential of SVV-001. Using recombinant SVV-001 3Cpro, we measured cleavage kinetics of predicted SVV-001 3Cpro substrates. An efficient substrate, L/VP4 (kcat/KM = 1932 ± 183 M(-1s(-1, was further optimized by a P2' N→P substitution yielding L/VP4.1 (kcat/KM = 17446 ± 2203 M(-1s(-1. We also determined essential substrate amino acids by sequential N-terminal deletion and substitution of amino acids found in other picornavirus genera. A peptide corresponding to the L/VP4.1 substrate was selectively cleaved by SVV-001 3Cpro in vitro and was stable in human plasma. These data define an optimized peptide substrate for SVV-001 3Cpro, with direct implications for anti-cancer therapeutic development.

  13. Seneca Valley Virus 3Cpro Substrate Optimization Yields Efficient Substrates for Use in Peptide-Prodrug Therapy.

    Science.gov (United States)

    Miles, Linde A; Brennen, W Nathaniel; Rudin, Charles M; Poirier, John T

    2015-01-01

    The oncolytic picornavirus Seneca Valley Virus (SVV-001) demonstrates anti-tumor activity in models of small cell lung cancer (SCLC), but may ultimately need to be combined with cytotoxic therapies to improve responses observed in patients. Combining SVV-001 virotherapy with a peptide prodrug activated by the viral protease 3Cpro is a novel strategy that may increase the therapeutic potential of SVV-001. Using recombinant SVV-001 3Cpro, we measured cleavage kinetics of predicted SVV-001 3Cpro substrates. An efficient substrate, L/VP4 (kcat/KM = 1932 ± 183 M(-1)s(-1)), was further optimized by a P2' N→P substitution yielding L/VP4.1 (kcat/KM = 17446 ± 2203 M(-1)s(-1)). We also determined essential substrate amino acids by sequential N-terminal deletion and substitution of amino acids found in other picornavirus genera. A peptide corresponding to the L/VP4.1 substrate was selectively cleaved by SVV-001 3Cpro in vitro and was stable in human plasma. These data define an optimized peptide substrate for SVV-001 3Cpro, with direct implications for anti-cancer therapeutic development.

  14. Seneca Valley Virus 3Cpro Substrate Optimization Yields Efficient Substrates for Use in Peptide-Prodrug Therapy

    Science.gov (United States)

    Miles, Linde A.; Brennen, W. Nathaniel; Rudin, Charles M.; Poirier, John T.

    2015-01-01

    The oncolytic picornavirus Seneca Valley Virus (SVV-001) demonstrates anti-tumor activity in models of small cell lung cancer (SCLC), but may ultimately need to be combined with cytotoxic therapies to improve responses observed in patients. Combining SVV-001 virotherapy with a peptide prodrug activated by the viral protease 3Cpro is a novel strategy that may increase the therapeutic potential of SVV-001. Using recombinant SVV-001 3Cpro, we measured cleavage kinetics of predicted SVV-001 3Cpro substrates. An efficient substrate, L/VP4 (kcat/KM = 1932 ± 183 M-1s-1), was further optimized by a P2’ N→P substitution yielding L/VP4.1 (kcat/KM = 17446 ± 2203 M-1s-1). We also determined essential substrate amino acids by sequential N-terminal deletion and substitution of amino acids found in other picornavirus genera. A peptide corresponding to the L/VP4.1 substrate was selectively cleaved by SVV-001 3Cpro in vitro and was stable in human plasma. These data define an optimized peptide substrate for SVV-001 3Cpro, with direct implications for anti-cancer therapeutic development. PMID:26069962

  15. Structure of human aspartyl aminopeptidase complexed with substrate analogue: insight into catalytic mechanism, substrate specificity and M18 peptidase family

    Directory of Open Access Journals (Sweden)

    Chaikuad Apirat

    2012-06-01

    Full Text Available Abstract Backround Aspartyl aminopeptidase (DNPEP, with specificity towards an acidic amino acid at the N-terminus, is the only mammalian member among the poorly understood M18 peptidases. DNPEP has implicated roles in protein and peptide metabolism, as well as the renin-angiotensin system in blood pressure regulation. Despite previous enzyme and substrate characterization, structural details of DNPEP regarding ligand recognition and catalytic mechanism remain to be delineated. Results The crystal structure of human DNPEP complexed with zinc and a substrate analogue aspartate-β-hydroxamate reveals a dodecameric machinery built by domain-swapped dimers, in agreement with electron microscopy data. A structural comparison with bacterial homologues identifies unifying catalytic features among the poorly understood M18 enzymes. The bound ligands in the active site also reveal the coordination mode of the binuclear zinc centre and a substrate specificity pocket for acidic amino acids. Conclusions The DNPEP structure provides a molecular framework to understand its catalysis that is mediated by active site loop swapping, a mechanism likely adopted in other M18 and M42 metallopeptidases that form dodecameric complexes as a self-compartmentalization strategy. Small differences in the substrate binding pocket such as shape and positive charges, the latter conferred by a basic lysine residue, further provide the key to distinguishing substrate preference. Together, the structural knowledge will aid in the development of enzyme-/family-specific aminopeptidase inhibitors.

  16. Substrate preference of the HIF-prolyl hydroxylase-2 (PHD2) and substrate-induced conformational change.

    Science.gov (United States)

    Pektas, Serap; Knapp, Michael J

    2013-09-01

    HIF prolyl-4-hydroxylase 2 (PHD2) is a non-heme Fe, 2-oxoglutarate (2OG) dependent dioxygenase that regulates the hypoxia inducible transcription factor (HIF) by hydroxylating two conserved prolyl residues in N-terminal oxygen degradation domain (NODD) and C-terminal oxygen degradation domain (CODD) of HIF-1α. Prior studies have suggested that the substrate preference of PHD2 arises from binding contacts with the β2β3 loop of PHD2. In this study we tested the substrate selectivity of PHD2 by kinetic competition assays, varied ionic strength, and global protein flexibility using amide H/D exchange (HDX). Our results revealed that PHD2 preferred CODD by 20-fold over NODD and that electrostatics influenced this effect. Global HDX monitored by mass spectrometry indicated that binding of Fe(II) and 2OG stabilized the overall protein structure but the saturating concentrations of either NODD or CODD caused an identical change in protein flexibility. These observations imply that both substrates stabilize the β2β3 loop to the same extent. Under unsaturated substrate conditions NODD led to a higher HDX rate than CODD due to its lower binding affinity to PHD2. Our results suggest that loop closure is the dominant contributor to substrate selectivity in PHD2.

  17. RFID and Memory Devices Fabricated Integrally on Substrates

    Science.gov (United States)

    Schramm, Harry F.

    2004-01-01

    Electronic identification devices containing radio-frequency identification (RFID) circuits and antennas would be fabricated integrally with the objects to be identified, according to a proposal. That is to say, the objects to be identified would serve as substrates for the deposition and patterning of the materials of the devices used to identify them, and each identification device would be bonded to the identified object at the molecular level. Vacuum arc vapor deposition (VAVD) is the NASA derived process for depositing layers of material on the substrate. This proposal stands in contrast to the current practice of fabricating RFID and/or memory devices as wafer-based, self-contained integrated-circuit chips that are subsequently embedded in or attached to plastic cards to make smart account-information cards and identification badges. If one relies on such a chip to store data on the history of an object to be tracked and the chip falls off or out of the object, then one loses both the historical data and the means to track the object and verify its identity electronically. Also, in contrast is the manufacturing philosophy in use today to make many memory devices. Today s methods involve many subtractive processes such as etching. This proposal only uses additive methods, building RFID and memory devices from the substrate up in thin layers. VAVD is capable of spraying silicon, copper, and other materials commonly used in electronic devices. The VAVD process sprays most metals and some ceramics. The material being sprayed has a very strong bond with the substrate, whether that substrate is metal, ceramic, or even wood, rock, glass, PVC, or paper. An object to be tagged with an identification device according to the proposal must be compatible with a vacuum deposition process. Temperature is seldom an issue as the substrate rarely reaches 150 F (66 C) during the deposition process. A portion of the surface of the object would be designated as a substrate for

  18. Ductile film delamination from compliant substrates using hard overlayers

    Science.gov (United States)

    Cordill, M.J.; Marx, V.M.; Kirchlechner, C.

    2014-01-01

    Flexible electronic devices call for copper and gold metal films to adhere well to polymer substrates. Measuring the interfacial adhesion of these material systems is often challenging, requiring the formulation of different techniques and models. Presented here is a strategy to induce well defined areas of delamination to measure the adhesion of copper films on polyimide substrates. The technique utilizes a stressed overlayer and tensile straining to cause buckle formation. The described method allows one to examine the effects of thin adhesion layers used to improve the adhesion of flexible systems. PMID:25641995

  19. Substrate-facilitated nanoparticle sintering and component interconnection procedure.

    Science.gov (United States)

    Allen, Mark; Leppäniemi, Jaakko; Vilkman, Marja; Alastalo, Ari; Mattila, Tomi

    2010-11-26

    Room temperature substrate-facilitated sintering of nanoparticles is demonstrated using commercially available silver nanoparticle ink and inkjet printing substrates. The sintering mechanism is based on the chemical removal of the nanoparticle stabilizing ligand and is shown to provide conductivity above one-fourth that of bulk silver. A novel approach to attach discrete components to printed conductors is presented, where the sintered silver provides the metallic interconnects with good electrical and mechanical properties. A process for printing and chip-on-demand assembly is suggested.

  20. Effects of Substrate Permeation on Kinetics of Phenol Biodegradation

    Institute of Scientific and Technical Information of China (English)

    冀秀玲; 张金利; 李Wei; 韩振亭; 王一平

    2003-01-01

    Based on the theory of substrate permeation through the cytoplasmic membrane,and considering the effect of initial concentration of substrate,a new kinetic model of phenol degradation process was proposed,Comparing with the widely used Haldane model,which is greatly dependent on the initial phenol concentration,our model can be used to simulate the phenol degradation process in a wide range of initial phenol concentration by using only one set of model parameters ,Therefore,this new kinetic model has much more potential applications to industrial design and operation.

  1. Optimization of Substrate Feeding for Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Huusom, Jakob Kjøbsted; Nordblad, Mathias

    to be effective in mitigating the effects of substrate inhibition. Using enzymatic biodiesel production as a case study, the volumetric productivity of the reactor is increased while minimizing inactivation of the enzyme due to the alcohol. This is done by using a simple optimization routine where the substrate...... (both the vegetable oil and alcohol) feed rate/concentration is manipulated simultaneously. The results of the simulation were tested in the laboratory and are sufficiently positive to suggest the implementation of a feeding strategy for large scale enzymatic biodiesel production....

  2. Optimization of Substrate Feeding for Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Huusom, Jakob Kjøbsted; Nordblad, Mathias

    2013-01-01

    to be effective in mitigating the effects of substrate inhibition. Using enzymatic biodiesel production as a case study, the volumetric productivity of the reactor is increased while minimizing inactivation of the enzyme due to the alcohol. This is done by using a simple optimization routine where the substrate...... (both the vegetable oil and alcohol) feed rate/concentration is manipulated simultaneously. The results of the simulation were tested in the laboratory and are sufficiently positive to suggest the implementation of a feeding strategy for large scale enzymatic biodiesel production...

  3. Laser sintering of conductive carbon paste on plastic substrate

    Science.gov (United States)

    Kinzel, Edward C.; Kelkar, Rohan; Xu, Xianfan

    2010-02-01

    This work investigates fabrication of functional conductive carbon paste onto a plastic substrate using a laser. The method allows simultaneous sintering, patterning, and functionalization of the carbon paste. Experiments are carried out to optimize the laser processing parameters. It is shown that sheet resistance values obtained by laser sintering are close to the one specified by the manufacturer using conventional sintering method. Additionally, a heat transfer analysis using numerical methods is conducted to understand the relationship between the temperature during sintering and the sheet resistance values of sintered carbon wires. The process developed in this work has the potential of producing carbon-based electronic components on low cost plastic substrates.

  4. Fabrication of hexagonal gallium nitride films on silicon (111) substrates

    Institute of Scientific and Technical Information of China (English)

    YANG Li; XUE Chengshan; WANG Cuimei; LI Huaixiang; REN Yuwen

    2003-01-01

    Hexagonal gallium nitride films were successfully fabricated through ammoniating Ga2O3 films deposited on silicon (111 ) substrates by electrophoresis. The structure, composition, and surface morphology of the formed films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM),and transmission electron microscopy (TEM). The measurement results reveal that the polycrystalline GaN films with hexagonal wurtzite structure were successfully grown on the silicon (111) substrates. Preliminary results suggest that varying the ammoniating temperature has obvious effect on the quality of the GaN films formed with this method.

  5. Copolymerization on Selective Substrates: Experimental Test and Computer Simulations.

    Science.gov (United States)

    Kozhunova, Elena Yu; Gavrilov, Alexey A; Zaremski, Mikhail Yu; Chertovich, Alexander V

    2017-03-28

    We explore the influence of a selective substrate on the composition and sequence statistics during the free radical copolymerization. In particular, we study the radical copolymerization of styrene and acrylic acid in bulk and in silica pores of different sizes. We show that the substrate affects both polymer composition and sequence statistics. We use dissipative particle dynamics simulations to study the polymerization process in detail, trying to pinpoint the parameters responsible for the observed differences in the polymer chain composition and sequences. The magnitude of the observed effect depends on the fraction of adsorbed monomer units, which cannot be described in the framework of the copolymerization theories based on the terminal unit model.

  6. Conductive and robust nitride buffer layers on biaxially textured substrates

    Science.gov (United States)

    Sankar, Sambasivan [Chicago, IL; Goyal, Amit [Knoxville, TN; Barnett, Scott A [Evanston, IL; Kim, Ilwon [Skokie, IL; Kroeger, Donald M [Knoxville, TN

    2009-03-31

    The present invention relates to epitaxial, electrically conducting and mechanically robust, cubic nitride buffer layers deposited epitaxially on biaxially textured substrates such as metals and alloys. The invention comprises of a biaxially textured substrate with epitaxial layers of nitrides. The invention also discloses a method to form such epitaxial layers using a high rate deposition method as well as without the use of forming gases. The invention further comprises epitaxial layers of oxides on the biaxially textured nitride layer. In some embodiments the article further comprises electromagnetic devices which may have superconducting properties.

  7. Integrated information theory: from consciousness to its physical substrate.

    Science.gov (United States)

    Tononi, Giulio; Boly, Melanie; Massimini, Marcello; Koch, Christof

    2016-07-01

    In this Opinion article, we discuss how integrated information theory accounts for several aspects of the relationship between consciousness and the brain. Integrated information theory starts from the essential properties of phenomenal experience, from which it derives the requirements for the physical substrate of consciousness. It argues that the physical substrate of consciousness must be a maximum of intrinsic cause-effect power and provides a means to determine, in principle, the quality and quantity of experience. The theory leads to some counterintuitive predictions and can be used to develop new tools for assessing consciousness in non-communicative patients.

  8. Rectangular and Circular Antenna Design on Thick Substrate

    CERN Document Server

    kumar, Harsh

    2010-01-01

    Millimeter wave technology being an emerging area is still very undeveloped. A substantial research needs to be done in this area as its applications are numerous. In the present endeavor, a rectangular patch antenna is designed on thick substrate and simulated using SONNET software, also a novel analysis technique is developed for circular patch antenna for millimeter wave frequency. The antenna is designed at 39 GHz on thick substrate and has been analyzed and simulated.The results of the theoretical analysis are in good agreement with the simulated results.

  9. GeSn/Ge multiquantum well photodetectors on Si substrates.

    Science.gov (United States)

    Oehme, M; Widmann, D; Kostecki, K; Zaumseil, P; Schwartz, B; Gollhofer, M; Koerner, R; Bechler, S; Kittler, M; Kasper, E; Schulze, J

    2014-08-15

    Vertical incidence GeSn/Ge multiquantum well (MQW) pin photodetectors on Si substrates were fabricated with a Sn concentration of 7%. The epitaxial structure was grown with a special low temperature molecular beam epitaxy process. The Ge barrier in the GeSn/Ge MQW was kept constant at 10 nm. The well width was varied between 6 and 12 nm. The GeSn/Ge MQW structures were grown pseudomorphically with the in-plane lattice constant of the Ge virtual substrate. The absorption edge shifts to longer wavelengths with thicker QWs in agreement with expectations from smaller quantization energies for the thicker QWs.

  10. Substrate Activity Screening (SAS) and Related Approaches in Medicinal Chemistry.

    Science.gov (United States)

    Gladysz, Rafaela; Lambeir, Anne-Marie; Joossens, Jurgen; Augustyns, Koen; Van der Veken, Pieter

    2016-03-04

    Substrate activity screening (SAS) was presented a decade ago by Ellman and co-workers as a straightforward methodology for the identification of fragment-sized building blocks for enzyme inhibitors. Ever since, SAS and variations derived from it have been successfully applied to the discovery of inhibitors of various families of enzymatically active drug targets. This review covers key achievements and challenges of SAS and related methodologies, including the modified substrate activity screening (MSAS) approach. Special attention is given to the kinetic and thermodynamic aspects of these methodologies, as a thorough understanding thereof is crucial for successfully transforming the identified fragment-sized hits into potent inhibitors.

  11. A method of manufacturing graduated substrates for a semiconductor laser

    Energy Technology Data Exchange (ETDEWEB)

    Yosikava, A.; Kadzumura, K.; Ota, K.; Sugino, T.; Vada, M.

    1984-01-12

    A method is patented for manufacturing a substrate with a graduated design for a semiconductor laser with a long service life and the necessary optical characteristics in a 1.5 micrometer spectral range. The laser is manufactured using a GaAs substrate with an active zone based on GaxAll-xAs. In order to achieve this goal, the active layer is equipped with a so called diffusion window whose diameter is chosen so that the threshold pumping current of the laser is less than 30 milliamperes.

  12. System and process for aluminization of metal-containing substrates

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Yeong-Shyung; Stevenson, Jeffry W

    2015-11-03

    A system and method are detailed for aluminizing surfaces of metallic substrates, parts, and components with a protective alumina layer in-situ. Aluminum (Al) foil sandwiched between the metallic components and a refractory material when heated in an oxidizing gas under a compression load at a selected temperature forms the protective alumina coating on the surface of the metallic components. The alumina coating minimizes evaporation of volatile metals from the metallic substrates, parts, and components in assembled devices during operation at high temperature that can degrade performance.

  13. System in biology leading to cell pathology: stable protein-protein interactions after covalent modifications by small molecules or in transgenic cells

    Directory of Open Access Journals (Sweden)

    Malina Halina Z

    2011-01-01

    Full Text Available Abstract Background The physiological processes in the cell are regulated by reversible, electrostatic protein-protein interactions. Apoptosis is such a regulated process, which is critically important in tissue homeostasis and development and leads to complete disintegration of the cell. Pathological apoptosis, a process similar to apoptosis, is associated with aging and infection. The current study shows that pathological apoptosis is a process caused by the covalent interactions between the signaling proteins, and a characteristic of this pathological network is the covalent binding of calmodulin to regulatory sequences. Results Small molecules able to bind covalently to the amino group of lysine, histidine, arginine, or glutamine modify the regulatory sequences of the proteins. The present study analyzed the interaction of calmodulin with the BH3 sequence of Bax, and the calmodulin-binding sequence of myristoylated alanine-rich C-kinase substrate in the presence of xanthurenic acid in primary retinal epithelium cell cultures and murine epithelial fibroblast cell lines transformed with SV40 (wild type [WT], Bid knockout [Bid-/-], and Bax-/-/Bak-/- double knockout [DKO]. Cell death was observed to be associated with the covalent binding of calmodulin, in parallel, to the regulatory sequences of proteins. Xanthurenic acid is known to activate caspase-3 in primary cell cultures, and the results showed that this activation is also observed in WT and Bid-/- cells, but not in DKO cells. However, DKO cells were not protected against death, but high rates of cell death occurred by detachment. Conclusions The results showed that small molecules modify the basic amino acids in the regulatory sequences of proteins leading to covalent interactions between the modified sequences (e.g., calmodulin to calmodulin-binding sites. The formation of these polymers (aggregates leads to an unregulated and, consequently, pathological protein network. The results

  14. MARCKS Signaling Differentially Regulates Vascular Smooth Muscle and Endothelial Cell Proliferation through a KIS-, p27kip1- Dependent Mechanism.

    Directory of Open Access Journals (Sweden)

    Dan Yu

    Full Text Available Overexpression of the myristolated alanine-rich C kinase substrate (MARCKS occurs in vascular proliferative diseases such as restenosis after bypass surgery. MARCKS knockdown results in arrest of vascular smooth muscle cell (VSMC proliferation with little effect on endothelial cell (EC proliferation. We sought to identify the mechanism of differential regulation by MARCKS of VSMC and EC proliferation in vitro and in vivo.siRNA-mediated MARCKS knockdown in VSMCs inhibited proliferation and prevented progression from phase G0/G1 to S. Protein expression of the cyclin-dependent kinase inhibitor p27kip1, but not p21cip1 was increased by MARCKS knockdown. MARCKS knockdown did not affect proliferation in VSMCs derived from p27kip1-/- mice indicating that the effect of MARCKS is p27kip1-dependent. MARCKS knockdown resulted in decreased phosphorylation of p27kip1 at threonine 187 and serine 10 as well as, kinase interacting with stathmin (KIS, cyclin D1, and Skp2 expression. Phosphorylation of p27kip1 at serine 10 by KIS is required for nuclear export and degradation of p27kip1. MARCKS knockdown caused nuclear trapping of p27kip1. Both p27kip1 nuclear trapping and cell cycle arrest were released by overexpression of KIS, but not catalytically inactive KIS. In ECs, MARCKS knockdown paradoxically increased KIS expression and cell proliferation. MARCKS knockdown in a murine aortic injury model resulted in decreased VSMC proliferation determined by bromodeoxyuridine (BrdU integration assay, and inhibition of vascular wall thickening. MARCKS knockdown increased the rate of re-endothelialization.MARCKS knockdown arrested VSMC cell cycle by decreasing KIS expression. Decreased KIS expression resulted in nuclear trapping of p27kip1 in VSMCs. MARCKS knockdown paradoxically increased KIS expression in ECs resulting in increased EC proliferation. MARCKS knockdown significantly attenuated the VSMC proliferative response to vascular injury, but accelerated

  15. Method of producing an electronic unit having a polydimethylsiloxane substrate and circuit lines

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, James Courtney (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA); Maghribi, Mariam N. (Livermore, CA); Benett, William J. (Livermore, CA); Hamilton, Julie K. (Tracy, CA); Tovar, Armando R. (San Antonio, TX)

    2012-06-19

    A system of metalization in an integrated polymer microsystem. A flexible polymer substrate is provided and conductive ink is applied to the substrate. In one embodiment the flexible polymer substrate is silicone. In another embodiment the flexible polymer substrate comprises poly(dimethylsiloxane).

  16. Engineering plasmon dispersion relations : hybrid nanoparticle chain - substrate plasmon polaritons

    NARCIS (Netherlands)

    Compaijen, Paul J.; Malyshev, Victor A.; Knoester, Jasper

    2015-01-01

    We consider the dispersion relations of the optical excitations in a chain of silver nanoparticles situated above a metal substrate and show that they are hybrid plasmon polaritons, composed of localized surface plasmons and surface plasmon polaritons. We demonstrate a strong dependence of the syste

  17. Mo-Si-B-Based Coatings for Ceramic Base Substrates

    Science.gov (United States)

    Perepezko, John Harry (Inventor); Sakidja, Ridwan (Inventor); Ritt, Patrick (Inventor)

    2015-01-01

    Alumina-containing coatings based on molybdenum (Mo), silicon (Si), and boron (B) ("MoSiB coatings") that form protective, oxidation-resistant scales on ceramic substrate at high temperatures are provided. The protective scales comprise an aluminoborosilicate glass, and may additionally contain molybdenum. Two-stage deposition methods for forming the coatings are also provided.

  18. Temperature and substrate on Plukenetia volubilis L. seed germination

    Directory of Open Access Journals (Sweden)

    Givanildo Z. da Silva

    Full Text Available ABSTRACT The objective of this work was to evaluate the effect of temperature and substrate on the germination of P. volubilis seeds. Seeds harvested from 25 matrix plants were submitted, in two studies, to conditions of (i sowing in rolled paper towel at the temperatures of 10, 15, 20, 25, 30, 35, 40, and 45 °C, for the evaluation of germination, first count of germination, germination speed index and mean time for germination, and (ii sowing in the substrates paper towel, sand, Bioplant®, Bioplant® and micron, superfine, fine, medium and coarse vermiculite. The same evaluations mentioned in the first study were conducted at the temperature of 30 oC, as well as plant growth. The treatment replicates were distributed in a completely randomized block design and the effects of temperature were compared by polynomial regression analysis. The substrates were compared by the Scott-Knott test at 0.05 probability level. The data show that the ideal range of temperature for the germination of P. volubilis is between 25 and 30 °C. The temperature of 20 °C is the minimum for germination and those above 35 °C are lethal to these seeds. The most favorable substrate for P. volubilis seed germination is micron or fine vermiculite.

  19. The technology of microcircuit assembly on flexible polyimide substrate

    Directory of Open Access Journals (Sweden)

    Plis N. I.

    2010-10-01

    Full Text Available The research is devoted to technology of microcircuit assembly on flexible polyimide substrate. It is proved that such microcircuits provide high reliability and have advantage over other IC models when applied in hermetic micro-assemblies in microelectronic devices that operate under high accelerations, shocks and strong radiation.

  20. Wide bandwidth nanowire electromechanics on insulating substrates at room temperature

    Science.gov (United States)

    Sebastian, Abhilash; Mathew, John; Sengupta, Shamashis; Gokhale, Maheshwar; Bhattacharya, Arnab; Deshmukh, Mandar

    2013-03-01

    We present a simple fabrication scheme for nano-scale devices on insulating substrates. Doubly clamped InAs nanowire resonators with local gate configuration are fabricated on sapphire substrates. Parasitic capacitance is reduced on insulating substrates thus enabling measurements at all temperatures and particularly above room temperature, an essential requirement for NEMS sensors. Mechanical motion of the nanowire is capacitively actuated and detected using a network analyser. This technique provides wide bandwidth radio frequency transduction and allows the nanowire oscillations to be probed at a much faster rate compared to mixing techniques. Both in-plane and out-of-plane vibrational modes of the nanowire are observed and the non-linear response of the resonators is studied. Quality factor of the resonator increases at low temperatures. We also study the relation between mechanical motion and thermal strains in the nanowire. This opens up a new approach in studying thermal properties of nanostructures. Our method of fabrication can be extended to NEMS devices on flexible substrates and other nanostructures.

  1. Substrate Reinforcement and Dialectal Differences in Melanesian Pidgin.

    Science.gov (United States)

    Siegel, Jeff

    1998-01-01

    Illustrates substrate reinforcement in the development of three current dialects of Melanesian Pidgin. Evidence of earlier variability is presented and the sociolinguistic conditions that later led to greater stability are described. Grammatical features that differentiate the dialects are examined. For each feature, it is shown that at least two…

  2. Laser cladding of Ni-based alloy on copper substrate

    Institute of Scientific and Technical Information of China (English)

    Fang Liu; Changsheng Liu; Xingqi Tao; Suiyuan Chen

    2006-01-01

    The laser cladding of Ni1015 alloy on Cu substrate was prepared by a high power continuous wave CO2 laser. Its microstructure was analyzed by optical microscope (OM), scanning electron microscope (SEM), and X-Ray diffraction (XRD). The average microhardness of the cladding coating was Hv 280, which was almost three times of that of the Cu substrate (Hv 85). OM and SEM observations showed that the obtained coating had a smooth and uniform surface, as well as a metallurgical combination with the Cu substrate without cracks and pores at the interface. With the addition of copper into the nickel-based alloy, the differences of thermal expansion coefficient and melting point between the interlayer and cladding were reduced, which resulted in low stresses during rapid cooling. Moreover, large amount of (Cu, Ni) solid solution formed a metallurgical bonding between the cladding coating and the substrate, which also relaxed the stresses, leading to the reduction of interfacial cracks and pores after laser cladding.

  3. Glycine betaine as a direct substrate for methanogens (Methanococcoides spp.).

    Science.gov (United States)

    Watkins, Andrew J; Roussel, Erwan G; Parkes, R John; Sass, Henrik

    2014-01-01

    Nine marine methanogenic Methanococcoides strains, including the type strains of Methanococcoides methylutens, M. burtonii, and M. alaskense, were tested for the utilization of N-methylated glycines. Three strains (NM1, PM2, and MKM1) used glycine betaine (N,N,N-trimethylglycine) as a substrate for methanogenesis, partially demethylating it to N,N-dimethylglycine, whereas none of the strains used N,N-dimethylglycine or sarcosine (N-methylglycine). Growth rates and growth yields per mole of substrate with glycine betaine (3.96 g [dry weight] per mol) were similar to those with trimethylamine (4.11 g [dry weight] per mol). However, as glycine betaine is only partially demethylated, the yield per methyl group was significantly higher than with trimethylamine. If glycine betaine and trimethylamine are provided together, trimethylamine is demethylated to dimethyl- and methylamine with limited glycine betaine utilization. After trimethylamine is depleted, dimethylamine and glycine betaine are consumed rapidly, before methylamine. Glycine betaine extends the range of substrates that can be directly utilized by some methanogens, allowing them to gain energy from the substrate without the need for syntrophic partners.

  4. High Tc YBCO superconductor deposited on biaxially textured Ni substrate

    Science.gov (United States)

    Budai, John D.; Christen, David K.; Goyal, Amit; He, Qing; Kroeger, Donald M.; Lee, Dominic F.; List, III, Frederick A.; Norton, David P.; Paranthaman, Mariappan; Sales, Brian C.; Specht, Eliot D.

    1999-01-01

    A superconducting article includes a biaxially-textured Ni substrate, and epitaxial buffer layers of Pd (optional), CeO.sub.2 and YSZ, and a top layer of in-plane aligned, c-axis oriented YBCO having a critical current density (J.sub.c) in the range of at least 100,000 A/cm.sup.2 at 77 K.

  5. Wetting morphologies and their transitions in grooved substrates

    Energy Technology Data Exchange (ETDEWEB)

    Seemann, Ralf; Bommer, Stefan; Herrmann, Carsten; Michler, Dominik [Experimental Physics, Saarland University, D-66123 Saarbruecken (Germany); Brinkmann, Martin; Herminghaus, Stephan; Khare, Krishnacharya; Kostourou, Konstantina; Gurevich, Evgeny [Max Planck Institute for Dynamics and Self-Organization, D-37073 Goettingen (Germany); Law, Bruce M; McBride, Sean, E-mail: r.seemann@physik.uni-saarland.de [Department of Physics, Kansas State University, Manhattan, KS 66506 (United States)

    2011-05-11

    When exposed to a partially wetting liquid, many natural and artificial surfaces equipped with complex topographies display a rich variety of liquid interfacial morphologies. In the present article, we focus on a few simple paradigmatic surface topographies and elaborate on the statics and dynamics of the resulting wetting morphologies. It is demonstrated that the spectrum of wetting morphologies increases with increasing complexity of the groove structure. On elastically deformable substrates, additional structures in the liquid morphologies can be observed, which are caused by deformations of the groove geometry in the presence of capillary forces. The emergence of certain liquid morphologies in grooves can be actively controlled by changes in wettability and geometry. For electrically conducting solid substrates, the apparent contact angle can be varied by electrowetting. This allows, depending on groove geometry, a reversible or irreversible transport of liquid along surface grooves. In the case of irreversible liquid transport in triangular grooves, the dynamics of the emerging instability is sensitive to the apparent hydrodynamic slip at the substrate. On elastic substrates, the geometry can be varied in a straightforward manner by stretching or relaxing the sample. The imbibition velocity in deformable grooves is significantly reduced compared to solid grooves, which is a result of the microscopic deformation of the elastic groove material close to the three phase contact line.

  6. Influence of substrate and film thickness on polymer LIPSS formation

    Science.gov (United States)

    Cui, Jing; Nogales, Aurora; Ezquerra, Tiberio A.; Rebollar, Esther

    2017-02-01

    Here we focus on the influence of both, substrate and film thickness on polymer Laser Induced Periodic Surface Structures (LIPSS) formation in polymer films. For this aim a morphological description of ripples structures generated on spin-coated polystyrene (PS) films by a linearly polarized laser beam with a wavelength of 266 nm is presented. The influence of different parameters on the quality and characteristics of the formed laser-induced periodic surface structures (LIPSS) was investigated. We found that well-ordered LIPSS are formed either on PS films thinner than 200 nm or thicker than 400 nm supported on silicon substrates as well as on thicker free standing films. However less-ordered ripples are formed on silicon supported films with intermediate thicknesses in the range of 200-380 nm. The effect of the thermal and optical properties of the substrate on the quality of LIPSS was analyzed. Differences observed in the fluence and number of pulses needed for the onset of surface morphological modifications is explained considering two main effects which are: (1) The temperature increase on polymer surface induced by the action of cumulative laser irradiation and (2) The differences in thermal conductivity between the polymer and the substrate which strongly affect the heat dissipation generated by irradiation.

  7. Microplate Bioassay for Determining Substrate Selectivity of "Candida rugosa" Lipase

    Science.gov (United States)

    Wang, Shi-zhen; Fang, Bai-shan

    2012-01-01

    Substrate selectivity of "Candida rugosa" lipase was tested using "p"-nitrophenyl esters of increasing chain length (C[subscript 1], C[subscript 7], C[subscript 15]) using the high-throughput screening method. A fast and easy 96-well microplate bioassay was developed to help students learn and practice biotechnological specificity screen. The…

  8. Profluorescent substrates for the screening of olefin metathesis catalysts.

    Science.gov (United States)

    Reuter, Raphael; Ward, Thomas R

    2015-01-01

    Herein we report on a 96-well plate assay based on the fluorescence resulting from the ring-closing metathesis of two profluorophoric substrates. To demonstrate the validity of the approach, four commercially available ruthenium-metathesis catalysts were evaluated in six different solvents. The results from the fluorescent assay agree well with HPLC conversions, validating the usefulness of the approach.

  9. Profluorescent substrates for the screening of olefin metathesis catalysts

    Directory of Open Access Journals (Sweden)

    Raphael Reuter

    2015-10-01

    Full Text Available Herein we report on a 96-well plate assay based on the fluorescence resulting from the ring-closing metathesis of two profluorophoric substrates. To demonstrate the validity of the approach, four commercially available ruthenium-metathesis catalysts were evaluated in six different solvents. The results from the fluorescent assay agree well with HPLC conversions, validating the usefulness of the approach.

  10. Profluorescent substrates for the screening of olefin metathesis catalysts

    Science.gov (United States)

    Reuter, Raphael

    2015-01-01

    Summary Herein we report on a 96-well plate assay based on the fluorescence resulting from the ring-closing metathesis of two profluorophoric substrates. To demonstrate the validity of the approach, four commercially available ruthenium-metathesis catalysts were evaluated in six different solvents. The results from the fluorescent assay agree well with HPLC conversions, validating the usefulness of the approach. PMID:26664607

  11. Method of Joining Graphite Fibers to a Substrate

    Science.gov (United States)

    Beringer, Durwood M. (Inventor); Caron, Mark E. (Inventor); Taddey, Edmund P. (Inventor); Gleason, Brian P. (Inventor)

    2014-01-01

    A method of assembling a metallic-graphite structure includes forming a wetted graphite subassembly by arranging one or more layers of graphite fiber material including a plurality of graphite fibers and applying a layer of metallization material to ends of the plurality of graphite fibers. At least one metallic substrate is secured to the wetted graphite subassembly via the layer of metallization material.

  12. Color contrast of red blood cells on solid substrate

    Science.gov (United States)

    Paiziev, Adkham A.

    2013-02-01

    In present study we developed the new method of colour visualization of red blood cells without using any chemical staining. The method based on physical phenomena a white light interference on thin transparent films. It is shown that in the case of thin human blood smears colour interference contrast occurs on solid polished substrates. The best contrast shows substrates with maximal refractive index (Mo, W, Si). These materials have been selected as substrate instead of ordinary microscopic slide in reflected light microscopy. It is shown that reflection of incident white light from blood cell surface and boundary cell-substrate generate two coherent lights. The second one (object signal) after passing through red blood cell gathers additional phase and after interference interaction with reference signal (light reflected from outer cell surface) enables cell image in colour. Number of blood smears of healthy persons (control) and patients who were diagnosed with cancer are presented. It is concluded that the offered method may be used as an effective diagnostic tool to detect early stage blood cells lesion by its interference painting in white light. Offered method may be used in research laboratories, hospitals, diagnostic centres, emergency medicine and other as complementary diagnostic tool to present convenient optical and electron microscopy technique.

  13. Transparent conducting oxides on polymeric substrates by pulsed laser deposition

    NARCIS (Netherlands)

    Dekkers, Jan Matthijn

    2007-01-01

    This thesis describes the research on thin films of transparent conducting oxides (TCOs) on polymeric substrates manufactured by pulsed laser deposition (PLD). TCOs are an indispensable part in optoelectronic applications such as displays, solar cells, light-emitting diodes, etc. At present, in many

  14. Growth of white tabebuia seedlings in different substrates

    Directory of Open Access Journals (Sweden)

    Marichel Canazza de Macedo

    2011-03-01

    Full Text Available The objective of this work was to evaluate the white tabebuia (Tabebuia roseo-alba (Ridl. Sandwith seedlings emergence and growth in the beds according to different substrates. Two independent experiments were conducted. The emergence study was carried out in six substrates: 1- Plantmax®; 2- vermiculite; 3- sand; 4- soil + sand (1:1; 5- soil + carbonized rice husk (1:1; 6- soil + sand + carbonized rice husk (2:1:1 (v/v, and the experiment was set up according to a three-replicate randomized complete-block design. The growth study of seedlings was carried out according to a five-replicate randomized complete-block design with five substrates: 1- soil + sand (1:1; 2- soil + semi decomposed chicken manure (1:1; 3- soil + carbonized rice husk (1:1; 4- soil + sand + semi decomposed chicken manure (1:1:1; 5- soil + sand + carbonized rice husk (1:1:1 (v/v. The height results of seedling emergence, emergence speed index and the stem height were observed with Plantmax®, vermiculite, soil + carbonized rice husk and soil + sand + carbonized rice husk. The best results of seedling height, stem diameter, chlorophyll index, leaf area, root length and the stem dry mass weight and root were observed in the substrates with semi decomposed chicken manure. It is recommended the use of P, V, SC or SAC for seedling germination and emergence and SACF or SCF for seedling growth of white tabebuia.

  15. Electrowetting-driven oscillating drops sandwiched between two substrates

    NARCIS (Netherlands)

    Mampallil, Dileep; Eral, H.B.; Staicu, A.D.; Mugele, F.; Ende, van den D.

    2013-01-01

    Drops sandwiched between two substrates are often found in lab-on-chip devices based on digital microfluidics. We excite azimuthal oscillations of such drops by periodically modulating the contact line via ac electrowetting. By tuning the frequency of the applied voltage, several shape modes can be

  16. Energy substrates to support glutamatergic and GABAergic synaptic function

    DEFF Research Database (Denmark)

    Schousboe, Arne; Bak, Lasse K; Sickmann, Helle M;

    2007-01-01

    Maintenance of glutamatergic and GABAergic activity requires a continuous supply of energy since the exocytotic processes as well as high affinity glutamate and GABA uptake and subsequent metabolism of glutamate to glutamine are energy demanding processes. The main energy substrate for the brain ...

  17. PROPERTIES OF NEW STRAINS CHEMOLITHOTROPHIC BACTERIA ISOLATED FROM INDUSTRIAL SUBSTRATES

    Directory of Open Access Journals (Sweden)

    I. A.

    2015-12-01

    Full Text Available The purpose of the research was determination of strains Acidithiobacillus ferrooxidans MFLv37 and Acidithiobacillus ferrooxidans MFLad27, isolated from aboriginal consortium of coal beneficiation dumps and fly ash from coal combustion, resistance to heavy metals, forming part of these waste, as well as adaption ability of the strains to new substrates. New strains increased resistance to heavy metal ions as compared to A. ferrooxidans standard and collection strains is found; minimal inhibitory concentrations of heavy and toxic metals are determined; a number of metals that have negative impact on growth of isolated cultures are identified. It is shown that the minimal metals concentrations, at which strains growth still happens, are several times higher than their concentrations in technogenic waste. It has been established that isolated strains differed in their ability to adapt, as well as in growth rate and substrates oxidation. This is due to the specific conditions of microbiocenoses formation in making and further storage of rock dumps and fly ash, whereof the appropriate strains are isolated. The investigations indicate the necessity in directional selection of strains that are resistant to the toxic compounds and are able to oxidize various mineral substrates, as well as in their adaptation to new substrates for the extraction of heavy metals.

  18. Substrate Acidification by Geranium (Pelargonium x Hortorum) I: Temperature Effects

    Science.gov (United States)

    Sudden pH decline (SPD) describes the situation where crops growing at an appropriate pH, suddenly (1-2 weeks) cause the substrate pH to shift downward one to two units. ‘Designer Dark Red’ Geraniums were grown in three experiments to test the effects of temperature on SPD. The first experiment te...

  19. Less Is More: Substrate Reduction Therapy for Lysosomal Storage Disorders

    Directory of Open Access Journals (Sweden)

    Maria Francisca Coutinho

    2016-07-01

    Full Text Available Lysosomal storage diseases (LSDs are a group of rare, life-threatening genetic disorders, usually caused by a dysfunction in one of the many enzymes responsible for intralysosomal digestion. Even though no cure is available for any LSD, a few treatment strategies do exist. Traditionally, efforts have been mainly targeting the functional loss of the enzyme, by injection of a recombinant formulation, in a process called enzyme replacement therapy (ERT, with no impact on neuropathology. This ineffectiveness, together with its high cost and lifelong dependence is amongst the main reasons why additional therapeutic approaches are being (and have to be investigated: chaperone therapy; gene enhancement; gene therapy; and, alternatively, substrate reduction therapy (SRT, whose aim is to prevent storage not by correcting the original enzymatic defect but, instead, by decreasing the levels of biosynthesis of the accumulating substrate(s. Here we review the concept of substrate reduction, highlighting the major breakthroughs in the field and discussing the future of SRT, not only as a monotherapy but also, especially, as complementary approach for LSDs.

  20. Nitrogen, salinity, substrates and growth of gloxinia and chrysanthemum

    NARCIS (Netherlands)

    Arnold Bik, R.A.

    1970-01-01

    The study was on the harmful effect of salinity on N utilization in the flower crops gloxinia (a salt-sensitive mesophytic semi-shade plant) and chrysanthemum (a salt- tolerant sun plant). For solid substrates (trials 2 and 3) the specific conductivity of the saturation extract (EC. in mmho per cm a

  1. Facile Synthesis of Photofunctional Nanolayer Coatings on Titanium Substrates.

    Science.gov (United States)

    Choi, Kyong-Hoon; Kim, Jung-Gil; Kang, Byungman; Kim, Ho-Joong; Park, Bong Joo

    2016-01-01

    We developed a two-step chemical bonding process using photosensitizer molecules to fabricate photofunctional nanolayer coatings on hematoporphyrin- (HP-) coated Ti substrates. In the first step, 3-aminopropyltriethoxysilane was covalently functionalized onto the surface of the Ti substrates to provide heterogeneous sites for immobilizing the HP molecules. Then, HP molecules with carboxyl groups were chemically attached to the amine-terminated nanolayer coatings via a carbodiimide coupling reaction. The microstructure and elemental and phase composition of the HP-coated Ti substrates were investigated using field-emission scanning electron microscopy and energy-dispersive X-ray spectrometry. The photophysical properties of the photofunctional nanolayer coatings were confirmed using reflectance ultraviolet-visible absorption and emission spectrophotometry. The singlet oxygen generation efficiency of the photofunctional nanolayer coatings was determined using the decomposition reaction of 1,3-diphenylisobenzofuran. The HP-coated Ti substrates exhibited good biocompatibility without any cytotoxicity, and these nanolayer coatings generated singlet oxygen, which can kill microorganisms using only visible light.

  2. Facile Synthesis of Photofunctional Nanolayer Coatings on Titanium Substrates

    Directory of Open Access Journals (Sweden)

    Kyong-Hoon Choi

    2016-01-01

    Full Text Available We developed a two-step chemical bonding process using photosensitizer molecules to fabricate photofunctional nanolayer coatings on hematoporphyrin- (HP- coated Ti substrates. In the first step, 3-aminopropyltriethoxysilane was covalently functionalized onto the surface of the Ti substrates to provide heterogeneous sites for immobilizing the HP molecules. Then, HP molecules with carboxyl groups were chemically attached to the amine-terminated nanolayer coatings via a carbodiimide coupling reaction. The microstructure and elemental and phase composition of the HP-coated Ti substrates were investigated using field-emission scanning electron microscopy and energy-dispersive X-ray spectrometry. The photophysical properties of the photofunctional nanolayer coatings were confirmed using reflectance ultraviolet-visible absorption and emission spectrophotometry. The singlet oxygen generation efficiency of the photofunctional nanolayer coatings was determined using the decomposition reaction of 1,3-diphenylisobenzofuran. The HP-coated Ti substrates exhibited good biocompatibility without any cytotoxicity, and these nanolayer coatings generated singlet oxygen, which can kill microorganisms using only visible light.

  3. SUBSTRATE EFFECTS ON VOC EMISSIONS FROM A LATEX PAINT

    Science.gov (United States)

    The effects of two substrates -- a stainless steel plate and a gypsum board -- on the volatile organic compound (VOC) emissions from a latex paint were evaluated by environmental chamber tests. It was found that the amount of VOCs emitted from the painted stainless steel was 2 to...

  4. Discovery of New Substrates for LuxAB Bacterial Bioluminescence.

    Science.gov (United States)

    Jiang, Tianyu; Wang, Weishan; Wu, Xingkang; Wu, Wenxiao; Bai, Haixiu; Ma, Zhao; Shen, Yuemao; Yang, Keqian; Li, Minyong

    2016-08-01

    In this article, four novel substrates with long halftime have been designed and synthesized successfully for luxAB bacterial bioluminescence. After in vitro and in vivo biological evaluation, these molecules can emit obvious bioluminescence emission with known bacterial luciferase, thus indicating a new promising approach to developing the bacterial bioluminescent system.

  5. Prebiotics and other microbial substrates for gut functionality

    NARCIS (Netherlands)

    Ouwehand, A.C.; Derrien, M.M.N.; Vos, de W.M.; Tiihonen, K.; Rautonen, N.

    2005-01-01

    The intestinal microbiota is of great importance to our health and wellbeing. Modulation of the intestinal microbiota by exogenous and endogenous substrates can be expected to improve various physiological functions of our body, not just those in the intestine. Recently, new targets such as immune f

  6. The ultratough peeling of elastic tapes from viscoelastic substrates

    Science.gov (United States)

    Afferrante, L.; Carbone, G.

    2016-11-01

    The peeling of an elastic thin tape from a flat smooth viscoelastic substrate is investigated. Based on a Green function approach and on the translational invariance, a closed form analytical solution is proposed, which takes into account the viscoelastic dissipation in the substrate material. We find that peeling is prevented from taking place, only when the external force is smaller than the one predicted by Kendall's formula for elastic tapes on rigid substrates. However, we also find that, regardless of the value of the applied force, steady state detachment may occur when the elastic tape is sufficiently stiff. In this case, the constant peeling velocity can be modulated by properly defining the geometrical parameters and the material properties of tape and viscoelastic foundation. On the other hand, for relatively high peeling angles or compliant tapes a threshold value of the peeling force is found, above which the steady-state equilibrium is no longer possible and unstable detachment occurs. The present study contributes to shed light on the behavior of pressure sensitive adhesives in contact with viscoelastic substrates like the human skin. At the same time, it can be considered a first step towards a better understanding of the effect of viscoelastic dissipation on the fracture behavior of solids.

  7. Droplets move over viscoelastic substrates by surfing a ridge

    NARCIS (Netherlands)

    Karpitschka, S.A.; Das, S.; Gorcum, van M.; Perrin, H.; Andreotti, B.; Snoeijer, J.H.

    2015-01-01

    Liquid drops on soft solids generate strong deformations below the contact line, resulting from a balance of capillary and elastic forces. The movement of these drops may cause strong, potentially singular dissipation in the soft solid. Here we show that a drop on a soft substrate moves by surfing a

  8. Evaporation of Sessile Droplets of Liquid on Solid Substrates

    Science.gov (United States)

    Semenov, S.; Starov, V. M.; Velarde, M. G.; Rubio, R. G.

    Evaporation of sessile droplets of liquid on solid substrates is considered here. Different parameters and processes influencing the evaporation rate are discussed. Cases of complete wetting and partial wetting with contact angle hysteresis are described mathematically. The influence of Kelvin's and kinetic effects and subsequent deviation from diffusion-limited evaporation is shown by means of computer simulations.

  9. Characterisation of CMP-sialic acid transporter substrate recognition

    NARCIS (Netherlands)

    Maggioni, A.; Itzstein, M. von; Guzman, I.B. Rodriguez; Ashikov, A.M.; Stephens, A.S.; Haselhorst, T.; Tiralongo, J.

    2013-01-01

    CMP-sialic acid transporter: We report an in-depth, multidisciplinary, structural study that has identified the amino acid residues intimately involved in CMP-sialic acid transporter (CST) substrate specificity. Our data provide a significant contribution towards a better understanding the structure

  10. A Novel Substrate Used for Simultaneous SERS and RAIR

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel substrate, whose silver particles were deposited on both sides of a slide, was made by silver mirror reaction. Its two sides had different thinness and reflectivity and they were suited for the test of surface enhanced Raman spectroscopy (SERS) and reflection absorption infrared spectroscopy (RAIR) technique respectively.

  11. Printed electronic switch on flexible substrates using printed microcapsules

    NARCIS (Netherlands)

    Cate, A.T. ten; Gaspar, C.H.; Virtanen, H.L.K.; Stevens, R.S.A.; Koldeweij, R.B.J.; Olkkonen, J.T.; Rentrop, C.H.A.; Smolander, M.H.

    2014-01-01

    Printed electronics, the manufacturing of electronic components on large, flexible, and low-cost substrates by printing techniques, can facilitate widespread, very low-cost electronics for consumer applications and disposable devices. New technologies are needed to create functional components in th

  12. Novel interconnection processes for low cost PEN/PET substrates

    NARCIS (Netherlands)

    Brand, J. van den; Kusters, R.; Fledderus, H.; Rubingh, J.E.J.M.; Podprocky, T.; Dietzel, A.H.

    2009-01-01

    Recently a new class of flexible electronics is starting to emerge which is most effectively termed 'printed electronics'. This term often refers to all-printed, cost effective, smart electronic products that will find a wide range of applications in large quantities in our society. The substrate ma

  13. Substrate-enzyme interactions and catalytic mechanism in phospholipase C

    DEFF Research Database (Denmark)

    Byberg, J R; Jørgensen, Flemming Steen; Hansen, S;

    1992-01-01

    Based on the high-resolution X-ray crystallographic structure of phospholipase C from Bacillus cereus, the orientation of the phosphatidylcholine substrate in the active site of the enzyme is proposed. The proposal is based on extensive calculations using the GRID program and molecular mechanics ...

  14. Modelling of Substrate Noise and Mitigation Schemes for UWB Systems

    DEFF Research Database (Denmark)

    Shen, Ming; Mikkelsen, Jan H.; Larsen, Torben

    2012-01-01

    The last chapter of this first part of the book, chapter seven, is devoted to Modeling of Substrate Noise and Mitigation Schemes for Ultrawideband (UWB) systems, and is written by Ming Shen, Jan H. Mikkelsen, and Torben Larsen from Aalborg University, Denmark. In highly integrated mixed-mode desi...

  15. Ecomorphology of Astyanax species in streams with different substrates

    Directory of Open Access Journals (Sweden)

    Marcela A. Souza

    2014-02-01

    Full Text Available In the present study, we assessed the ecomorphology of two species of Astyanax in streams with different substrates found in the Rio São Francisco Basin. The dominant substrate of each stream was defined as either "fine" (0 to 2 mm, "gravel" (2 to 250 mm, "rock" (> 250 mm, or "leaf bank". We analyzed a total of 22 ecomorphological attributes of Astyanax intermedius Eigenmann, 1908 (127 individuals and Astyanax rivularis (Lütken, 1875 (238 individuals adults. We detected significant ecomorphological differences between the populations of A. rivularis and A. intermedius from habitats with different types of substrates. However, the two species did not show the same morphological differences depending on the type of substrate. These results confirmed the hypothesis that individuals from environments with different characteristics may have different ecomorphological patterns. Knowing that morphology is associated with habitat use and available resources, the loss of a resource or a modification in the environment may directly affect the permanence of a species, leading to a loss of morphologic diversity.

  16. Mechanical Characterization of Flexible and Stretchable Electronic Substrates

    NARCIS (Netherlands)

    Wang, L.

    2010-01-01

    Conventional IC packages form a rigid shell around silicon IC dies. Their purpose is to provide environmental protection, electrical interconnect and heat dissipation. Despite the fact that majority of current silicon IC′s are realized in a very thin top layer of the silicon substrate (<10µm), the t

  17. Chemical analysis of substrates with controlled release fertilizer

    NARCIS (Netherlands)

    Kreij, de C.

    2004-01-01

    Water-soluble fertilizer added to media containing controlled release fertilizer cannot be analysed with the 1:1.5 volume water extract, because the latter increases the element content in the extract. During storage and stirring or mixing the substrate with the extractant, part of the controlled re

  18. Effect of sample preparation on charged impurities in graphene substrates

    Science.gov (United States)

    Burson, K. M.; Dean, C. R.; Watanabe, K.; Taniguchi, T.; Hone, J.; Kim, P.; Cullen, W. G.; Fuhrer, M. S.

    2013-03-01

    The mobility of graphene as fabricated on SiO2 has been found to vary widely depending on sample preparation conditions. Additionally, graphene mobility on SiO2 appears to be limited to ~20,000 cm2/Vs, likely due to charged impurities in the substrate. Here we present a study of the effect of fabrication procedures on substrate charged impurity density (nimp) utilizing ultrahigh-vacuum Kelvin probe force microscopy. We conclude that even minimal SEM exposure, as from e-beam lithography, induces an increased impurity density, while heating reduces the number of charges for sample substrates which already exhibit a higher impurity density. We measure both SiO2 and h-BN and find that all nimp values observed for SiO2 are higher than those observed for h-BN; this is consistent with the observed improvement in mobility for graphene devices fabricated on h-BN over those fabricated on SiO2 substrates. This work was supported by the US ONR MURI program, and the University of Maryland NSF-MRSEC under Grant No. DMR 05-20471.

  19. Towards easily reproducible nano-structured SERS substrates

    DEFF Research Database (Denmark)

    Schmidt, Michael Stenbæk; Boisen, Anja; Hübner, Jörg

    2009-01-01

    In this paper we present a quick and easy method for producing relatively large areas of substrate that enhance the Raman effect, using standard semiconductor processing techniques such as reactive ion etching of silicon and electron beam metal deposition. As standard cleanroom processes are used...

  20. Bryophyte spore germinability is inhibited by peatland substrates

    Science.gov (United States)

    Bu, Zhao-Jun; Li, Zhi; Liu, Li-Jie; Sundberg, Sebastian; Feng, Ya-Min; Yang, Yun-He; Liu, Shuang; Song, Xue; Zhang, Xing-Lin

    2017-01-01

    Bryophyte substrates and species may affect spore germination through allelopathy. Polytrichum strictum is currently expanding in peatlands in north-eastern China - is this an effect of its superior spore germinability or do its gametophytes have a stronger allelopathic effect than do Sphagnum? We conducted a spore burial experiment to test the effect of species identity, substrate and water table depth (WTD) on spore germinability and bryophyte allelopathic effect with P. strictum and two Sphagnum species (S. palustre and S. magellanicum). After 5 months of burial during a growing season, the spores were tested for germinability. Allelopathic effect of bryophyte substrates was assessed by the difference between spore germinability after being stored inside or outside the substrates. After burial, more than 90% of the spores lost their germinability across all three species due to ageing and allelopathy. Spore germinability differed among species, where the spores in S. palustre had a higher germination frequency than those in P. strictum. The three bryophytes maintained a higher germinability in Sphagnum than in Polytrichum hummocks, probably due to a stronger allelopathic effect of P. strictum. Water table drawdown by 10 cm increased germinability by more than 60% across the three species. The study indicates that P. strictum does not possess an advantage regarding spore germination but rather its gametophytes have a stronger allelopathic effect. Due to the weaker inhibitive effect of Sphagnum gametophytes, P. strictum may have a potential establishment superiority over Sphagnum in peatlands, in addition to a better drought tolerance, which may explain its current expansion.

  1. Growth of Candida guilliermondii FTI 20037 on mixed substrate

    Directory of Open Access Journals (Sweden)

    Patrick V. Gurgel

    1998-01-01

    Full Text Available Candida guilliermondii FTI 20037 was grown on a mixed substrate comprising glucose and xylose. Inocula were grown using xylose or glucose as carbon source. Results showed that xylose utilization was delayed until glucose was utilized. Inoculum prepared on glucose showed a lag phase in xylose consumption. Cell mass production was higher when glucose was utilized during fermentation.

  2. Detecting substrate engagement: responses of tarsal campaniform sensilla in cockroaches.

    Science.gov (United States)

    Zill, Sasha N; Keller, Bridget R; Chaudhry, Sumaiya; Duke, Elizabeth R; Neff, David; Quinn, Roger; Flannigan, Clay

    2010-06-01

    Sensory signals of contact and engagement with the substrate are important in the control and adaptation of posture and locomotion. We characterized responses of campaniform sensilla, receptors that encode forces as cuticular strains, in the tarsi (feet) of cockroaches using neurophysiological techniques and digital imaging. A campaniform sensillum on the fourth tarsal segment was readily identified by its large action potential in nerve recordings. The receptor discharged to contractions of the retractor unguis muscle, which engages the pretarsus (claws and arolium) with the substrate. We mimicked the effects of muscle contractions by applying displacements to the retractor apodeme (tendon). Sensillum firing did not occur to unopposed movements, but followed engagement of the claws with an object. Vector analysis of forces suggested that resisted muscle contractions produce counterforces that axially compress the tarsal segments. Close joint packing of tarsal segments was clearly observed following claw engagement. Physiological experiments showed that the sensillum responded vigorously to axial forces applied directly to the distal tarsus. Discharges of tarsal campaniform sensilla could effectively signal active substrate engagement when the pretarsal claws and arolium are used to grip the substrate in climbing, traversing irregular terrains or walking on inverted surfaces.

  3. Micronutrient availability from steel slag amendment in peatmoss substrates

    Science.gov (United States)

    The objective of this research was to determine the suitability of a steel slag product for supplying micronutrients to container-grown floriculture crops. Geranium (Pelargonium xhortorum 'Maverick Red') and tomato (Solanum lycopersicon 'Megabite') were grown in 11.4 cm containers with a substrate ...

  4. Egg-laying substrate selection for optimal camouflage by quail.

    Science.gov (United States)

    Lovell, P George; Ruxton, Graeme D; Langridge, Keri V; Spencer, Karen A

    2013-02-04

    Camouflage is conferred by background matching and disruption, which are both affected by microhabitat. However, microhabitat selection that enhances camouflage has only been demonstrated in species with discrete phenotypic morphs. For most animals, phenotypic variation is continuous; here we explore whether such individuals can select microhabitats to best exploit camouflage. We use substrate selection in a ground-nesting bird (Japanese quail, Coturnix japonica). For such species, threat from visual predators is high and egg appearance shows strong between-female variation. In quail, variation in appearance is particularly obvious in the amount of dark maculation on the light-colored shell. When given a choice, birds consistently selected laying substrates that made visual detection of their egg outline most challenging. However, the strategy for maximizing camouflage varied with the degree of egg maculation. Females laying heavily maculated eggs selected the substrate that more closely matched egg maculation color properties, leading to camouflage through disruptive coloration. For lightly maculated eggs, females chose a substrate that best matched their egg background coloration, suggesting background matching. Our results show that quail "know" their individual egg patterning and seek out a nest position that provides most effective camouflage for their individual phenotype.

  5. Large area flexible SERS active substrates using engineered nanostructures

    Science.gov (United States)

    Chung, Aram J.; Huh, Yun Suk; Erickson, David

    2011-07-01

    Surface enhanced Raman scattering (SERS) is an analytical sensing method that provides label-free detection, molecularly specific information, and extremely high sensitivity. The Raman enhancement that makes this method attractive is mainly attributed to the local amplification of the incident electromagnetic field that occurs when a surface plasmon mode is excited at a metallic nanostructure. Here, we present a simple, cost effective method for creating flexible, large area SERS-active substrates using a new technique we call shadow mask assisted evaporation (SMAE). The advantage of large, flexible SERS substrates such as these is they have more area for multiplexing and can be incorporated into irregular surfaces such as clothing. We demonstrate the formation of four different types of nanostructure arrays (pillar, nib, ellipsoidal cylinder, and triangular tip) by controlling the evaporation angle, substrate rotation, and deposition rate of metals onto anodized alumina nanoporous membranes as large as 27 mm. In addition, we present experimental results showing how a hybrid structure comprising of gold nanospheres embedded in a silver nano-pillar structure can be used to obtain a 50× SERS enhancement over the raw nanoparticles themselves.Surface enhanced Raman scattering (SERS) is an analytical sensing method that provides label-free detection, molecularly specific information, and extremely high sensitivity. The Raman enhancement that makes this method attractive is mainly attributed to the local amplification of the incident electromagnetic field that occurs when a surface plasmon mode is excited at a metallic nanostructure. Here, we present a simple, cost effective method for creating flexible, large area SERS-active substrates using a new technique we call shadow mask assisted evaporation (SMAE). The advantage of large, flexible SERS substrates such as these is they have more area for multiplexing and can be incorporated into irregular surfaces such as

  6. Characterization of silicon carbide coatings on Zircaloy-4 substrates

    Science.gov (United States)

    Al-Olayyan, Yousif Abdullah

    The lifetime of light water reactor (LWR) fuels is limited by the corrosion and degradation of Zircaloy cladding in the high temperature and high pressure operating conditions. As the thickness of the oxide layer increases, stresses build up in the oxide layer due to density differences between the oxide and the zirconium metal which lead to degradation and spallation of the oxide layer. The main objective of this research is to form protective coatings on the Zircaloy clad to prevent or at least slow the oxidation which can allow higher burnup of the fuel resulting in major benefits in plant safety and economics. Silicon carbide was identified as a candidate protective coating to reduce the corrosion and degradation of Zircaloy cladding. Silicon carbide coatings were deposited on Zircaloy substrates using plasma-assisted chemical vapor deposition (PE-CVD) and were found to be amorphous as determined by X-ray analysis. Since the adhesion of the films to the substrate was the most important property of a coating, scratch tests were used to assess the adhesion. The effects of different parameters on the test results including residual stresses, plastic deformation and friction between the stylus and the surface are discussed. Critical loads, characterized by continuous delamination of the SiC coatings deposited on Zircaloy-4, occurred at 0.5--2.5 N. The experimental results indicated that all SiC coatings used in this project, without exception, showed an adhesive failure when tested by scratch and indentation tests. Plastic deformation of the substrate due to compressive stresses induced by the scratch stylus caused flaking of the films at the interface, which was attributed to the low interfacial toughness. The effects of film thickness and substrate surface treatment on the quality and adhesion of SiC coatings were studied in detail. Thick films (5mum) exhibited extensive cracking. The scratch tests indicated higher adhesion with intermediate substrate surface

  7. Static and kinetic friction characteristics of nanowire on different substrates

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun-Joon [Department of Precision Mechanical Engineering, Kyungpook National University, Sangju 37224 (Korea, Republic of); Nguyen, Gia Hau; Ky, Dinh Le Cao; Tran, Da Khoa [School of Mechanical Engineering, University of Ulsan, Ulsan 44610 (Korea, Republic of); Jeon, Ki-Joon [Department of Environmental Engineering, Inha University, Incheon 22212 (Korea, Republic of); Chung, Koo-Hyun, E-mail: khchung@ulsan.ac.kr [School of Mechanical Engineering, University of Ulsan, Ulsan 44610 (Korea, Republic of)

    2016-08-30

    Highlights: • Direct measurement of kinetic friction of oxidized Si NW using AFM. • Determination of static friction of oxidized Si NW from most bent state. • Friction characteristics of oxidized Si NW on SiO{sub 2} and graphene. • Estimation of shear stress between cylindrical NW and flat substrate. • No significant dependence of shear stress on NW radius. - Abstract: Friction characteristics of nanowires (NWs), which may be used as building blocks for nano-devices, are crucial, especially for cases where contact sliding occurs during the device operation. In this work, the static and kinetic friction characteristics of oxidized Si NWs deposited on thermally grown SiO{sub 2} and chemical vapor-deposited single layer graphene were investigated using an atomic force microscope (AFM). Kinetic friction between the oxidized Si NWs and the substrates was directly measured by the AFM. Static friction was also obtained from the most bent state of the NWs using the individually determined elastic moduli of the NWs from kinetic friction experiments based on elastic beam theory. Furthermore, the shear stress between the oxidized Si NWs and the substrates was estimated based on adhesive contact theory. It was found that both static and kinetic friction increased as the radius of the NWs increased. The friction of the oxidized Si NWs on the graphene substrate was found to be smaller than that on the SiO{sub 2} substrate, which suggests that chemical vapor-deposited graphene can be used as a lubricant or as a protective layer in nano-devices to reduce friction. The shear stress estimated from the kinetic friction data between the oxidized Si NWs and the SiO{sub 2} substrate ranged from 7.5 to 12.3 MPa while that between the oxidized Si NWs and the graphene substrate ranged from 4.7 to 7.0 MPa. The result also indicated that the dependence of shear stress on the radius of the NWs was not significant. These findings may provide insight into the friction characteristics

  8. Evaluation of different substrates for inkjet printing of rasagiline mesylate.

    Science.gov (United States)

    Genina, Natalja; Janßen, Eva Maria; Breitenbach, Armin; Breitkreutz, Jörg; Sandler, Niklas

    2013-11-01

    The main goal of the present study was to evaluate applicability of the different model substrates, namely orodispersible films (ODFs), porous copy paper sheets, and water impermeable transparency films (TFs) in preparation of the inkjet-printed drug-delivery systems. Rasagiline mesylate (RM) was used as a low-dose active pharmaceutical ingredient (API). Flexible doses of the drug in a single unit were obtained by printing several subsequent layers on top of the already printed ones, using an off-the-shelf consumer thermal inkjet (TIJ) printer. The produced drug-delivery systems were subjected to microscopic and chemical analysis together with solid-state characterization and content uniformity studies. The results revealed that RM recrystallized on the surface of ODFs and TFs, and the printed crystals were arranged in lines. No drug crystals were detected after printing on the surface of the copy paper due to absorption of the ink into the matrix of the substrate. The best linear correlation between the dose of the drug and the number of the printing layers was obtained for the porous copy paper. The other two substrates showed poor linearity and unacceptable standard deviations of the printed drug substance due to limited absorption of the API ink into the carrier. The shear stress between the substrate, the print head, and the paper feeding rollers caused smearing of the drug that had been surface-deposited during the earlier printing cycles. In conclusion, this study indicates that the edible substrates with absorption properties similar to copy paper are favorable for successful preparation of drug-delivery systems by TIJ printers.

  9. Fluorogenic Substrates for Visualizing Acidic Organelle Enzyme Activities.

    Directory of Open Access Journals (Sweden)

    Fiona Karen Harlan

    Full Text Available Lysosomes are acidic cytoplasmic organelles that are present in all nucleated mammalian cells and are involved in a variety of cellular processes including repair of the plasma membrane, defense against pathogens, cholesterol homeostasis, bone remodeling, metabolism, apoptosis and cell signaling. Defects in lysosomal enzyme activity have been associated with a variety of neurological diseases including Parkinson's Disease, Lysosomal Storage Diseases, Alzheimer's disease and Huntington's disease. Fluorogenic lysosomal staining probes were synthesized for labeling lysosomes and other acidic organelles in a live-cell format and were shown to be capable of monitoring lysosomal metabolic activity. The new targeted substrates were prepared from fluorescent dyes having a low pKa value for optimum fluorescence at the lower physiological pH found in lysosomes. They were modified to contain targeting groups to direct their accumulation in lysosomes as well as enzyme-cleavable functions for monitoring specific enzyme activities using a live-cell staining format. Application to the staining of cells derived from blood and skin samples of patients with Metachromatic Leukodystrophy, Krabbe and Gaucher Diseases as well as healthy human fibroblast and leukocyte control cells exhibited localization to the lysosome when compared with known lysosomal stain LysoTracker® Red DND-99 as well as with anti-LAMP1 Antibody staining. When cell metabolism was inhibited with chloroquine, staining with an esterase substrate was reduced, demonstrating that the substrates can be used to measure cell metabolism. When applied to diseased cells, the intensity of staining was reflective of lysosomal enzyme levels found in diseased cells. Substrates specific to the enzyme deficiencies in Gaucher or Krabbe disease patient cell lines exhibited reduced staining compared to that in non-diseased cells. The new lysosome-targeted fluorogenic substrates should be useful for research

  10. Physical and chemical properties of substrates produced using macrophytes aquatics

    Directory of Open Access Journals (Sweden)

    Walda Monteiro Farias

    2013-12-01

    Full Text Available Aquatic macrophytes are widely used as bioindicators of water quality because their proliferation usually occurs in eutrophic water sources and has hit several parts of Brazil and the world, restricted the multiple uses of aquatic ecosystems. However, this group of plants is able to retain considerable amounts of nutrients, presenting high productivity and high growth rate, thus, a good source of biomass for use in the production of substrates. In order to evaluate the potential of aquatic macrophytes water hyacinth (Eichhornia crassipes Solms., water lettuce (Pistia stratiotes L. and cattail (Typha domingensis Pers. in the production of substrates was performed in this work, the physical and chemical characterization and evaluation of the degree of humification. The treatments were arranged in a 3 × 4 factorial, completely randomized design with three replications. All substrates produced with 100% macrophyte density present within the limits of 400 kg m-3, considered ideal. The composite substrates with water hyacinth and water lettuce are with the electrical conductivity of 0,79 a 2,49 dS m-1 within recommended. organic compounds produced are considered mature and have high levels of nitrogen phosphorus and potassium; The substrate produced with 70% water lettuce +30 % dung and 70% composed of cattail manure +20% +10% topsoil and 70 +30% cattail manure have C/N ratio within the considered ideal; the humification ratio and humification index, except for the four treatments (70 % water lettuce manure +30%, 5 (100% water hyacinth and 8 (70% water hyacinth manure +30% are within the considered ideal, the percentage of humic acids and polymerization rate, except for treatments 1 (100% water lettuce and 12 (100% cattail, are shown below the ideal.

  11. Substrate recognition and catalysis by flap endonucleases and related enzymes.

    Science.gov (United States)

    Tomlinson, Christopher G; Atack, John M; Chapados, Brian; Tainer, John A; Grasby, Jane A

    2010-04-01

    FENs (flap endonucleases) and related FEN-like enzymes [EXO-1 (exonuclease-1), GEN-1 (gap endonuclease 1) and XPG (xeroderma pigmentosum complementation group G)] are a family of bivalent-metal-ion-dependent nucleases that catalyse structure-specific hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair and recombination. In the case of FENs, the ability to catalyse reactions on a variety of substrates has been rationalized as a result of combined functional and structural studies. Analyses of FENs also exemplify controversies regarding the two-metal-ion mechanism. However, kinetic studies of T5FEN (bacteriophage T5 FEN) reveal that a two-metal-ion-like mechanism for chemical catalysis is plausible. Consideration of the metallobiochemistry and the positioning of substrate in metal-free structures has led to the proposal that the duplex termini of substrates are unpaired in the catalytically active form and that FENs and related enzymes may recognize breathing duplex termini within more complex structures. An outstanding issue in FEN catalysis is the role played by the intermediate (I) domain arch or clamp. It has been proposed that FENs thread the 5'-portion of their substrates through this arch, which is wide enough to accommodate single-stranded, but not double-stranded, DNA. However, FENs exhibit gap endonuclease activity acting upon substrates that have a region of 5'-duplex. Moreover, the action of other FEN family members such as GEN-1, proposed to target Holliday junctions without termini, appears incompatible with a threading mechanism. An alterative is that the I domain is used as a clamp. A future challenge is to clarify the role of this domain in FENs and related enzymes.

  12. Substrate recognition mechanism of VAMP/synaptobrevin-cleaving clostridial neurotoxins.

    Science.gov (United States)

    Sikorra, Stefan; Henke, Tina; Galli, Thierry; Binz, Thomas

    2008-07-25

    Botulinum neurotoxins (BoNTs) and tetanus neurotoxin (TeNT) inhibit neurotransmitter release by proteolyzing a single peptide bond in one of the three soluble N-ethylmaleimide-sensitive factor attachment protein receptors SNAP-25, syntaxin, and vesicle-associated membrane protein (VAMP)/synaptobrevin. TeNT and BoNT/B, D, F, and G of the seven known BoNTs cleave the synaptic vesicle protein VAMP/synaptobrevin. Except for BoNT/B and TeNT, they cleave unique peptide bonds, and prior work suggested that different substrate segments are required for the interaction of each toxin. Although the mode of SNAP-25 cleavage by BoNT/A and E has recently been studied in detail, the mechanism of VAMP/synaptobrevin proteolysis is fragmentary. Here, we report the determination of all substrate residues that are involved in the interaction with BoNT/B, D, and F and TeNT by means of systematic mutagenesis of VAMP/synaptobrevin. For each of the toxins, three or more residues clustered at an N-terminal site remote from the respective scissile bond are identified that affect solely substrate binding. These exosites exhibit different sizes and distances to the scissile peptide bonds for each neurotoxin. Substrate segments C-terminal of the cleavage site (P4-P4') do not play a role in the catalytic process. Mutation of residues in the proximity of the scissile bond exclusively affects the turnover number; however, the importance of individual positions at the cleavage sites varied for each toxin. The data show that, similar to the SNAP-25 proteolyzing BoNT/A and E, VAMP/synaptobrevin-specific clostridial neurotoxins also initiate substrate interaction, employing an exosite located N-terminal of the scissile peptide bond.

  13. Prediction of substrates for glutathione transferases by covalent docking.

    Science.gov (United States)

    Dong, Guang Qiang; Calhoun, Sara; Fan, Hao; Kalyanaraman, Chakrapani; Branch, Megan C; Mashiyama, Susan T; London, Nir; Jacobson, Matthew P; Babbitt, Patricia C; Shoichet, Brian K; Armstrong, Richard N; Sali, Andrej

    2014-06-23

    Enzymes in the glutathione transferase (GST) superfamily catalyze the conjugation of glutathione (GSH) to electrophilic substrates. As a consequence they are involved in a number of key biological processes, including protection of cells against chemical damage, steroid and prostaglandin biosynthesis, tyrosine catabolism, and cell apoptosis. Although virtual screening has been used widely to discover substrates by docking potential noncovalent ligands into active site clefts of enzymes, docking has been rarely constrained by a covalent bond between the enzyme and ligand. In this study, we investigate the accuracy of docking poses and substrate discovery in the GST superfamily, by docking 6738 potential ligands from the KEGG and MetaCyc compound libraries into 14 representative GST enzymes with known structures and substrates using the PLOP program [ Jacobson Proteins 2004 , 55 , 351 ]. For X-ray structures as receptors, one of the top 3 ranked models is within 3 Å all-atom root mean square deviation (RMSD) of the native complex in 11 of the 14 cases; the enrichment LogAUC value is better than random in all cases, and better than 25 in 7 of 11 cases. For comparative models as receptors, near-native ligand-enzyme configurations are often sampled but difficult to rank highly. For models based on templates with the highest sequence identity, the enrichment LogAUC is better than 25 in 5 of 11 cases, not significantly different from the crystal structures. In conclusion, we show that covalent docking can be a useful tool for substrate discovery and point out specific challenges for future method improvement.

  14. Substrate-dependent cell elasticity measured by optical tweezers indentation

    Science.gov (United States)

    Yousafzai, Muhammad S.; Ndoye, Fatou; Coceano, Giovanna; Niemela, Joseph; Bonin, Serena; Scoles, Giacinto; Cojoc, Dan

    2016-01-01

    In the last decade, cell elasticity has been widely investigated as a potential label free indicator for cellular alteration in different diseases, cancer included. Cell elasticity can be locally measured by pulling membrane tethers, stretching or indenting the cell using optical tweezers. In this paper, we propose a simple approach to perform cell indentation at pN forces by axially moving the cell against a trapped microbead. The elastic modulus is calculated using the Hertz-model. Besides the axial component, the setup also allows us to examine the lateral cell-bead interaction. This technique has been applied to measure the local elasticity of HBL-100 cells, an immortalized human cell line, originally derived from the milk of a woman with no evidence of breast cancer lesions. In addition, we have studied the influence of substrate stiffness on cell elasticity by performing experiments on cells cultured on two substrates, bare and collagen-coated, having different stiffness. The mean value of the cell elastic modulus measured during indentation was 26±9 Pa for the bare substrate, while for the collagen-coated substrate it diminished to 19±7 Pa. The same trend was obtained for the elastic modulus measured during the retraction of the cell: 23±10 Pa and 13±7 Pa, respectively. These results show the cells adapt their stiffness to that of the substrate and demonstrate the potential of this setup for low-force probing of modifications to cell mechanics induced by the surrounding environment (e.g. extracellular matrix or other cells).

  15. Uric acid and thiocyanate as competing substrates of lactoperoxidase.

    Science.gov (United States)

    Seidel, Antonia; Parker, Heather; Turner, Rufus; Dickerhof, Nina; Khalilova, Irada S; Wilbanks, Sigurd M; Kettle, Anthony J; Jameson, Guy N L

    2014-08-01

    The physiological function of urate is poorly understood. It may act as a danger signal, an antioxidant, or a substrate for heme peroxidases. Whether it reacts sufficiently rapidly with lactoperoxidase (LPO) to act as a physiological substrate remains unknown. LPO is a mammalian peroxidase that plays a key role in the innate immune defense by oxidizing thiocyanate to the bactericidal and fungicidal agent hypothiocyanite. We now demonstrate that urate is a good substrate for bovine LPO. Urate was oxidized by LPO to produce the electrophilic intermediates dehydrourate and 5-hydroxyisourate, which decayed to allantoin. In the presence of superoxide, high yields of hydroperoxides were formed by LPO and urate. Using stopped-flow spectroscopy, we determined rate constants for the reaction of urate with compound I (k1 = 1.1 × 10(7) M(-1) s(-1)) and compound II (k2 = 8.5 × 10(3) M(-1) s(-1)). During urate oxidation, LPO was diverted from its peroxidase cycle because hydrogen peroxide reacted with compound II to give compound III. At physiologically relevant concentrations, urate competed effectively with thiocyanate, the main substrate of LPO for oxidation, and inhibited production of hypothiocyanite. Similarly, hypothiocyanite-dependent killing of Pseudomonas aeruginosa was inhibited by urate. Allantoin was present in human saliva and associated with the concentration of LPO. When hydrogen peroxide was added to saliva, oxidation of urate was dependent on its concentration and peroxidase activity. Our findings establish urate as a likely physiological substrate for LPO that will influence host defense and give rise to reactive electrophilic metabolites.

  16. From UBE3A to Angelman syndrome: a substrate perspective

    Directory of Open Access Journals (Sweden)

    Gabrielle L Sell

    2015-09-01

    Full Text Available Angelman syndrome (AS is a debilitating neurodevelopmental disorder that is characterized by motor dysfunction, intellectual disability, speech impairment, seizures and common features of autism spectrum disorders (ASDs. Some of these AS related phenotypes can be seen in other neurodevelopmental disorders (Williams, 2011;Tan et al., 2014. AS patients commonly carry mutations that render the maternally inherited UBE3A gene nonfunctional. Duplication of the chromosomal region containing the UBE3A gene is associated with ASDs. Although the causative role for UBE3A gene mutations in AS is well established, a long-standing challenge in AS research has been to identify neural substrates of UBE3A, an E3 ubiquitin ligase. A prevailing hypothesis is that changes in UBE3A protein levels would alter the levels of a collection of protein substrates, giving rise to the unique phenotypic aspects of AS and possibly UBE3A associated ASDs. Interestingly, proteins altered in AS are linked to additional ASDs that are not previously associated with changes in UBE3A, indicating a possible molecular overlap underlying the broad-spectrum phenotypes of these neurogenetic disorders. This idea raises the possibility that there may exist a one-size-fits-all approach to the treatment of neurogenetic disorders with phenotypes overlapping AS. Furthermore, while a comprehensive list of UBE3A substrates and downstream affected pathways should be developed, this is only part of the story. The timing of when UBE3A protein functions, through either changes in UBE3A or possibly substrate expression patterns, appears to be critical for AS phenotype development. These data call for further investigation of UBE3A substrates and their timing of action relevant to AS phenotypes.

  17. Effects of Substrate Local Strain on Microstructure of Electrodeposited Aluminum Film

    Institute of Scientific and Technical Information of China (English)

    TAN Yuehua; YAN Bo; GAO Ge; YANG Yuxin

    2006-01-01

    The aluminum coating layer was formed on a copper substrate with local strain region by using the electrodeposited method. It was found that the particle shape of the coating deposited on the copper substrate is very sensitive to the strain extent of substrate. The large needle-like aluminum particles were observed on the substrate region with large local strain, indicating that substrate local strain may affect the shape of the deposited particles and promote the nucleation and growth of the deposited particles.

  18. Modeling Growth of Cellulomonas cellulans NRRL B 4567 under Substrate Inhibition During Cellulase Production

    OpenAIRE

    Agarwal, R; Mahanty, B.; Dasu, V. Venkata

    2009-01-01

    Cellulase production study was performed in shake flask and bioreactor system using Cellulomonas cellulans NRRL B 4567 for initial substrate concentration from γS0 = 2 to 12 g L–1. The growth, substrate uptake profile and enzyme activity at different initial substrate concentrations were measured. The results inferred the presence of substrate inhibition kinetics. Various substrate inhibition models were tested and parameters were estimated, using non-linear regression analysis. Han-Levenspie...

  19. Substrate-dependent modulation of CYP3A4 catalytic activity: analysis of 27 test compounds with four fluorometric substrates.

    Science.gov (United States)

    Stresser, D M; Blanchard, A P; Turner, S D; Erve, J C; Dandeneau, A A; Miller, V P; Crespi, C L

    2000-12-01

    Inhibition of cytochrome P450 catalytic activity is a principal mechanism for pharmacokinetic drug-drug interactions. Rapid, in vitro testing for cytochrome P450 inhibition potential is part of the current paradigm for identifying drug candidates likely to give such interactions. We have explored the extent that qualitative and quantitative inhibition parameters are dependent on the cytochrome P450 (CYP) 3A4 probe substrate. Inhibition potential (e.g., IC(50) values from 8-point inhibition curves) or activation potential for most compounds varied dramatically depending on the fluorometric probe substrates for CYP3A4 [benzyloxyresorufin (BzRes), 7-benzyloxy-4-trifluoromethylcoumarin (BFC), 7-benzyloxyquinoline (BQ), and dibenzylfluorescein (DBF)]. For 21 compounds that were primarily inhibitors, the range of IC(50) values for the four substrates varied from 2.1- to 195-fold with an average of 29-fold. While the rank order of sensitivity among the fluorometric substrates varied among the individual inhibitors, on average, BFC dealkylation was the most sensitive to inhibition, while BQ dealkylation was least sensitive. Partial inhibition was observed with BzRes and BQ but not for BFC and DBF. BzRes was more prone to activation, whereas dramatic changes in IC(50) values were observed when the BQ concentration was below the S(50). Three different correlation analyses indicated that IC(50) values with BFC, BQ, and DBF correlated well with each other, whereas the response with BzRes correlated more weakly with the other substrates. One of these correlation analyses was extended to the percent inhibition of 10 microM inhibitor with the standard CYP3A4 probe substrates testosterone, midazolam, and nifedipine. In this analysis the responses with BQ, BFC and DBF correlated well with testosterone and midazolam but more poorly with nifedipine. In the aggregate, BFC and DBF appear more suitable as an initial screen for CYP3A4 inhibition. However, the substrate-dependent effects

  20. Electrically robust silver nanowire patterns transferrable onto various substrates

    Science.gov (United States)

    Liu, Gui-Shi; Liu, Chuan; Chen, Hui-Jiuan; Cao, Wu; Qiu, Jing-Shen; Shieh, Han-Ping D.; Yang, Bo-Ru

    2016-03-01

    We report a facile technique for patterning and transferring silver nanowires (AgNWs) onto various substrates. By employing only UV/O3 and vapor treatment of hexamethyldisilazane (HMDS), we are able to accurately manipulate the surface energy via alternating the terminal groups of a polydimethylsiloxane (PDMS) substrate, so as to assist selective formation and exfoliation of AgNW films. A simple UV/O3 treatment on PDMS enables uniform, well-defined, and highly conductive patterns of AgNWs after spin-coating. A vapor treatment of HMDS lowers the surface energy of the oxidized PDMS so that the patterned AgNWs embedded in an epoxy resin (EPR) are cleanly transferred from the PDMS to the target substrate. It is found that the AgNW-EPR composite on polyethylene glycol terephthalate (PET) exhibits remarkable durability under the bending test, tape test, ultrasonic treatment in water, and immersion of chemical solvents. In addition, we demonstrate that the AgNW-EPR composite work well as conductive patterns on the oxidized PDMS, polyvinyl alcohol (PVA), paper, and curved glass. The facile technique extends the applicability of AgNWs in the field of electronics, and it is potentially applicable to other nanomaterials.We report a facile technique for patterning and transferring silver nanowires (AgNWs) onto various substrates. By employing only UV/O3 and vapor treatment of hexamethyldisilazane (HMDS), we are able to accurately manipulate the surface energy via alternating the terminal groups of a polydimethylsiloxane (PDMS) substrate, so as to assist selective formation and exfoliation of AgNW films. A simple UV/O3 treatment on PDMS enables uniform, well-defined, and highly conductive patterns of AgNWs after spin-coating. A vapor treatment of HMDS lowers the surface energy of the oxidized PDMS so that the patterned AgNWs embedded in an epoxy resin (EPR) are cleanly transferred from the PDMS to the target substrate. It is found that the AgNW-EPR composite on polyethylene

  1. Catalysis of protein disulfide bond isomerization in a homogeneous substrate.

    Science.gov (United States)

    Kersteen, Elizabeth A; Barrows, Seth R; Raines, Ronald T

    2005-09-13

    Protein disulfide isomerase (PDI) catalyzes the rearrangement of nonnative disulfide bonds in the endoplasmic reticulum of eukaryotic cells, a process that often limits the rate at which polypeptide chains fold into a native protein conformation. The mechanism of the reaction catalyzed by PDI is unclear. In assays involving protein substrates, the reaction appears to involve the complete reduction of some or all of its nonnative disulfide bonds followed by oxidation of the resulting dithiols. The substrates in these assays are, however, heterogeneous, which complicates mechanistic analyses. Here, we report the first analysis of disulfide bond isomerization in a homogeneous substrate. Our substrate is based on tachyplesin I, a 17-mer peptide that folds into a beta hairpin stabilized by two disulfide bonds. We describe the chemical synthesis of a variant of tachyplesin I in which its two disulfide bonds are in a nonnative state and side chains near its N and C terminus contain a fluorescence donor (tryptophan) and acceptor (N(epsilon)-dansyllysine). Fluorescence resonance energy transfer from 280 to 465 nm increases by 28-fold upon isomerization of the disulfide bonds into their native state (which has a lower E(o') = -0.313 V than does PDI). We use this continuous assay to analyze catalysis by wild-type human PDI and a variant in which the C-terminal cysteine residue within each Cys-Gly-His-Cys active site is replaced with alanine. We find that wild-type PDI catalyzes the isomerization of the substrate with kcat/K(M) = 1.7 x 10(5) M(-1) s(-1), which is the largest value yet reported for catalysis of disulfide bond isomerization. The variant, which is a poor catalyst of disulfide bond reduction and dithiol oxidation, retains virtually all of the activity of wild-type PDI in catalysis of disulfide bond isomerization. Thus, the C-terminal cysteine residues play an insignificant role in the isomerization of the disulfide bonds in nonnative tachyplesin I. We conclude

  2. Effects of substrate loading on enzymatic hydrolysis and viscosity of pretreated barley straw

    DEFF Research Database (Denmark)

    Rosgaard, L.; Andric, Pavle; Dam-Johansen, Kim;

    2007-01-01

    glucose concentration, 78 g/l, after 72 h of reaction, was obtained with an initial, full substrate loading of 15% dry matter weight/weight (w/w DM). Conversely, the glucose yields, in grams per gram of DM, were highest at lower substrate concentrations, with the highest glucose yield being 0.53 g/g DM...... for the reaction with a substrate loading of 5% w/w DM after 72 h. The reactions subjected to gradual loading of substrate or substrate plus enzymes to increase the substrate levels from 5 to 15% w/w DM, consistently provided lower concentrations of glucose after 72 h of reaction; however, the initial rates......In this study, the applicability of a "fed-batch" strategy, that is, sequential loading of substrate or substrate plus enzymes during enzymatic hydrolysis was evaluated for hydrolysis of steam-pretreated barley straw. The specific aims were to achieve hydrolysis of high substrate levels, low...

  3. Treatment of digested substrates for nitrogen removal and emission decrease

    Energy Technology Data Exchange (ETDEWEB)

    Bauermeister, U.; Spindler, H.; Wild, A. [GNS - Gesellschaft fuer Nachhaltige Stoffnutzung mbH, Halle/Saale (Germany)

    2006-07-01

    The production and application of biogas is well tried. Originally, the main goal of the biogas technology was the hygienization of the strong smelling manure from live stock. With change of priorities to an energetic application of the produced biogas, an enormous increase of the digested substrates was reached, which could lead to additional emission problems by using it as fertilizer. An important aim of the agricultural policy is to reduce emissions of ammonia and other compounds of nitrogen caused by agriculture into the air and the ground water. Therefore, it is necessary to know more about technical possibilities, reduction rates and the economy of reduction technologies. In combination with the fermentation process there are new opportunities of manure treatment to reduce emissions and to avoid over-fertilization. This presentation will give an introduction to the topic and to a new technology for separation of digested substrates into low emission fertilizers, called ANAStrip {sup registered} -process. (orig.)

  4. Selection of strains for shiitake production in axenic substrate.

    Science.gov (United States)

    Zied, Diego Cunha; Maciel, William Pereira; Marques, Simone Cristina; da Silveira E Santos, Débora Marques; Rinker, Danny Lee; Dias, Eustáquio Souza

    2016-10-01

    Shiitake mushroom consumption is increasing in Brazil. In addition to the implementation of new production methods, it is also important to increase productivity, quality and reduce production costs. In this study, six commercial Lentinula edodes strains were characterized for genetic diversity (rep-PCR analysis) and mushroom production (yield, number and weight of individual mushrooms) using different substrates and cultural conditions. All strains showed genetic differences by repetitive element palindromic based-polymerase chain reaction (rep-PCR). The richest substrate resulted in the greatest production under both environmental conditions. Strains LE4 and LE6 produced the majority of their mushrooms earlier than the other strains. The highest number of mushrooms was observed in the LE6 strain while the highest weights of individual mushrooms were observed in the LE4 strain. Controlled environmental conditions resulted in superior production for all strains, except for LE4, which had empirically greater yield in the semi-controlled environmental condition.

  5. Infrared specular reflection spectroscopy of rough metallic substrates.

    Science.gov (United States)

    Caron, Jerome; Jacquet, Denis

    2005-07-01

    A study of the infrared reflectance of rough metallic surfaces is presented. We show that one reflectance measurement, made in the specular direction under specific conditions, allows the accurate calculation of the shape of the roughness histogram. As a theoretical background, we use modified expressions from Kirchhoff theory for surface scattering. To illustrate our method, we present experimental results obtained with surfaces having a multimode histogram, which means having several different populations with distinct peaks. For these surfaces, we observe oscillations in the regularly decreasing reflectance (with decreasing wavelength) that are created by a partial interference phenomenon between the peaks. To our knowledge, this effect is presented for the first time in the literature. Our study demonstrates that some very useful information can be obtained in the infrared spectrum of metallic substrates, although they do not have any absorption band. We hope that our results help further the understanding of complex spectral data obtained on such scattering substrates covered with organic films.

  6. Synthesis of GaN films on porous silicon substrates

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A novel and simple method was employed to synthesize GaN films on porous silicon (PS) substrates. GaN films were obtained through the reaction between NH3 and Ga2O3 films deposited on the substrates with magnetron sputtering.Since GaN and PS are all good materials for luminescence, it is expected to obtain some new properties from GaN on PS.The samples were analyzed with X-ray diffraction (XRD) to identify crystalline structure. Fourier transmit infrared (FTIR)spectrum was used to analyze the chemical state of the samples. The films were observed with scanning electron microscopy (SEM) and were found to consist of many big crystal grains. Photoluminescence (PL) spectrum was used to illuminate the optical property of the GaN films.

  7. Computational approaches to substrate-based cell motility

    Science.gov (United States)

    Ziebert, Falko; Aranson, Igor S.

    2016-07-01

    Substrate-based crawling motility of eukaryotic cells is essential for many biological functions, both in developing and mature organisms. Motility dysfunctions are involved in several life-threatening pathologies such as cancer and metastasis. Motile cells are also a natural realisation of active, self-propelled 'particles', a popular research topic in nonequilibrium physics. Finally, from the materials perspective, assemblies of motile cells and evolving tissues constitute a class of adaptive self-healing materials that respond to the topography, elasticity and surface chemistry of the environment and react to external stimuli. Although a comprehensive understanding of substrate-based cell motility remains elusive, progress has been achieved recently in its modelling on the whole-cell level. Here we survey the most recent advances in computational approaches to cell movement and demonstrate how these models improve our understanding of complex self-organised systems such as living cells.

  8. Extracellular Protease Activity of Enteropathogenic Escherechia coli on Mucin Substrate

    Directory of Open Access Journals (Sweden)

    SRI BUDIARTI

    2007-03-01

    Full Text Available Enteropathogenic Escherichia coli (EPEC causes gastrointestinal infections in human. EPEC invasion was initiated by attachment and aggressive colonization on intestinal surface. Attachment of EPEC alter the intestine mucosal cells. Despite this, the pathogenic mechanism of EPEC infectior has not been fully understood. This research hypothesizes that extracellular proteolytic enzymes is necessary for EPEC colonization. The enzyme is secreted into gastrointestinal milieu and presumably destroy mucus layer cover the gastrointestinal tract. The objective of this study was to assay EPEC extracellular protease enzyme by using mucin substrate. The activity of EPEC extracellular proteolytic enzyme on 1% mucin substrate was investigated. Non-pathogenic E. coli was used as a negative control. Positive and tentative controls were Yersinia enterocolitica and Salmonella. Ten EPEC strains were assayed, seven of them were able to degrade mucin, and the highest activity was produced by K1.1 strain. Both positive and tentative controls also showed the ability to digest 0.20% mucin.

  9. Fracture and Delamination of Chromium Thin Films on Polymer Substrates

    Science.gov (United States)

    Cordill, M. J.; Taylor, A.; Schalko, J.; Dehm, G.

    2010-04-01

    New emerging technologies in the field of flexible electronic devices require that metal films adhere well and flex with polymer substrates. Common thin film materials used for these applications include copper (Cu) with an adhesion interlayer of chromium (Cr). Copper can be quite ductile and easily move with the polymer substrate. However, Cr is more brittle and fractures at lower strains than Cu. This study aims to examine the fracture and subsequent buckling and delamination of strained Cr films on polyimide (PI). In-situ scanning electron microscope (SEM) straining is used to systematically study the influence of film thickness on fracture and buckling strains. Film fracture and delamination depend on film thickness, and increases in crack and buckle density with decreasing thickness are explored by a shear lag model.

  10. Kovar Micro Heat Pipe Substrates for Microelectronic Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Benson, David A.; Burchett, Steven N.; Kravitz, Stanley H.; Robino, Charles V.; Schmidt, Carrie; Tigges, Chris P.

    1999-04-01

    We describe the development of a new technology for cooling microelectronics. This report documents the design, fabrication, and prototype testing of micro scale heat pipes embedded in a flat plate substrate or heat spreader. A thermal model tuned to the test results enables us to describe heat transfer in the prototype, as well as evaluate the use of this technology in other applications. The substrate walls are Kovar alloy, which has a coefficient of thermal expansion close to that of microelectronic die. The prototype designs integrating micro heat pipes with Kovar enhance thermal conductivity by more than a factor of two over that of Kovar alone, thus improving the cooling of micro-electronic die.

  11. Dual detection biosensor based on porous silicon substrate

    Energy Technology Data Exchange (ETDEWEB)

    Simion, Monica, E-mail: moni304ro@yahoo.com; Kusko, Mihaela; Mihalache, Iuliana; Brăgaru, Adina

    2013-11-20

    Due to the high surface-to-volume ratio (hundreds of m{sup 2}/cm{sup 3}) porous silicon became during the last years a good candidate material as substrate for biosensor application. Moreover, the versatility of surface chemistry allows different functionalization approaches and large number of molecules to be captured on well-defined areas. This paper reports a dual detection method for protein recognition processes developed on different nanostructured porous silicon (PS) substrates, based on using two complementary spectroscopic techniques: fluorescence and electrochemical impedance. The structures were tested for biomolecular recognition – biotin–strepavidin couples – in order to achieve an optimum surface for protein's immobilizations. Comparative analyses of the attachment degree and preservation of the biomolecules activity on the porous silicon surfaces and silicon slides are also described.

  12. Nanofabrication of SERS Substrates for Single/Few Molecules Detection

    KAUST Repository

    Melino, Gianluca

    2015-05-04

    Raman spectroscopy is among the most widely employed methods to investigate the properties of materials in several fields of study. Evolution in materials science allowed us to fabricate suitable substrates, at the nanoscale, capable to enhance the electromagnetic field of the signals coming from the samples which at this range turn out to be in most cases singles or a few molecules. This particular variation of the classical technique is called SERS (Surface Enanched Raman Spectroscopy). In this work, the enhancement of the electromagnetic field is obtained by manipulation of the optical properties of metals with respect to their size. By using electroless deposition (bottom up technique), gold and silver nanoparticles were deposited in nanostructured patterns obtained on silicon wafers by means of electron beam lithography (top down technique). Rhodamine 6G in aqueous solution at extremely low concentration (10-8 M) was absorbed on the resultant dimers and the collection of the Raman spectra demonstrated the high efficiency of the substrates.

  13. Selective growth of carbon nanotube on silicon substrates

    Institute of Scientific and Technical Information of China (English)

    ZOU Xiao-ping; H. ABE; T. SHIMIZU; A. ANDO; H. TOKUMOT; ZHU Shen-ming; ZHOU Hao-shen

    2006-01-01

    The carbon nanotube (CNT) growth of iron oxide-deposited trench-patterns and the locally-ordered CNT arrays on silicon substrate were achieved by simple thermal chemical vapor deposition(STCVD) of ethanol vapor. The CNTs were uniformly synthesized with good selectivity on trench-patterned silicon substrates. This fabrication process is compatible with currently used semiconductor-processing technologies,and the carbon-nanotube fabrication process can be widely applied for the development of electronic devices using carbon-nanotube field emitters as cold cathodes and can revolutionize the area of field-emitting electronic devices. The site-selective growth of CNT from an iron oxide nanoparticle catalyst patterned were also achieved by drying-mediated self-assembly technique. The present method offers a simple and cost-effective method to grow carbon nanotubes with self-assembled patterns.

  14. Polyaniline coating with various substrates for hexavalent chromium removal

    Science.gov (United States)

    Qiu, Bin; Xu, Cuixia; Sun, Dezhi; Wang, Qiang; Gu, Hongbo; Zhang, Xin; Weeks, Brandon L.; Hopper, Jack; Ho, Thomas C.; Guo, Zhanhu; Wei, Suying

    2015-04-01

    Hexavalent chromium (Cr(VI)) contamination is increasingly serious in surface water and groundwater, therefore, its removal attracts increasing attention due to its highly toxic to human health. The cost effective and sustainable adsorbents are urgently needed for the remediation of Cr(VI) pollution. Polyanline (PANI), a conductive polymer, has demonstrated a great performance on Cr(VI) removal. But the recycling is the challenge for its application due to its small size. The PANI coating with various substrates is an effective approach to solve this problem. The synthesis methods and applications of the PANI coated magnetic Fe3O4, carbon fabric and cellulose composites for the Cr(VI) removal were reviewed. Finally, this review analyzed the Cr(VI) removal mechanisms by the PANI composites considering the substrate and the PANI coating.

  15. PATCHY SILICA-COATED SILVER NANOWIRES AS SERS SUBSTRATES

    Energy Technology Data Exchange (ETDEWEB)

    Murph, S.; Murphy, C.

    2013-03-29

    We report a class of core-shell nanomaterials that can be used as efficient surface-enhancement Raman scattering (SERS) substrates. The core consists of silver nanowires, prepared through a chemical reduction process, that are used to capture 4- mercaptobenzoic acid (4-MBA), a model analyte. The shell was prepared through a modified Stöber method and consists of patchy or full silica coats. The formation of silica coats was monitored via transmission electron microscopy, UV-visible spectroscopy and phase-analysis light scattering for measuring effective surface charge. Surprisingly, the patchy silica coated silver nanowires are better SERS substrate than silver nanowires; nanomolar concentration of 4-MBA can be detected. In addition, “nano-matryoshka” configurations were used to quantitate/explore the effect of the electromagnetic field at the tips of the nanowire (“hot spots”) in the Raman scattering experiment.

  16. Graphene synthesis via magnetic inductive heating of copper substrates.

    Science.gov (United States)

    Piner, Richard; Li, Huifeng; Kong, Xianghua; Tao, Li; Kholmanov, Iskandar N; Ji, Hengxing; Lee, Wi Hyoung; Suk, Ji Won; Ye, Jongpil; Hao, Yufeng; Chen, Shanshan; Magnuson, Carl W; Ismach, Ariel F; Akinwande, Deji; Ruoff, Rodney S

    2013-09-24

    Scaling graphene growth using an oven to heat large substrates becomes less energy efficient as system size is increased. We report a route to graphene synthesis in which radio frequency (RF) magnetic fields inductively heat metal foils, yielding graphene of quality comparable to or higher than that of current chemical vapor deposition techniques. RF induction heating allows for rapid temperature ramp up/down, with great potential for large scale and rapid manufacturing of graphene with much better energy efficiency. Back-gated field effect transistors on a SiO2/Si substrate showed carrier mobility up to ∼14 000 cm(2) V(-1) s(-1) measured under ambient conditions. Many advantages of RF heating are outlined, and some fundamental aspects of this approach are discussed.

  17. Anchoring properties of substrate with a grating surface

    Institute of Scientific and Technical Information of China (English)

    Ye Wen-Jiang; Xing Hong-Yu; Yang Guo-Chen

    2007-01-01

    The anchoring properties of substrate with a grating surface are investigated analytically. The alignment of nematic liquid crystal (NLC) in a grating surface originates from two mechanisms, thus the anchoring energy consists of two parts. One originates from the interaction potential between NLC molecules and the molecules on the substrate surface,and the other stems from the increased elastic strain energy. Based on the two mechanisms, the expression of anchoring energy per unit area of a projected plane of this grating surface is deduced and called the equivalent anchoring energy formula. Both the strength and the easy direction of equivalent anchoring energy are a function of the geometrical parameters (amplitude and pitch) of a grating surface. By using this formula, the grating surface can be replaced by its projected plane and its anchoring properties can be described by the equivalent anchoring energy formula.

  18. Formation and characterization of DNA microarrays at silicon nitride substrates.

    Science.gov (United States)

    Manning, Mary; Redmond, Gareth

    2005-01-01

    A versatile method for direct, covalent attachment of DNA microarrays at silicon nitride layers, previously deposited by chemical vapor deposition at silicon wafer substrates, is reported. Each microarray fabrication process step, from silicon nitride substrate deposition, surface cleaning, amino-silanation, and attachment of a homobifunctional cross-linking molecule to covalent immobilization of probe oligonucleotides, is defined, characterized, and optimized to yield consistent probe microarray quality, homogeneity, and probe-target hybridization performance. The developed microarray fabrication methodology provides excellent (high signal-to-background ratio) and reproducible responsivity to target oligonucleotide hybridization with a rugged chemical stability that permits exposure of arrays to stringent pre- and posthybridization wash conditions through many sustained cycles of reuse. Overall, the achieved performance features compare very favorably with those of more mature glass based microarrays. It is proposed that this DNA microarray fabrication strategy has the potential to provide a viable route toward the successful realization of future integrated DNA biochips.

  19. Micromachined high-performance RF passives in CMOS substrate

    Science.gov (United States)

    Li, Xinxin; Ni, Zao; Gu, Lei; Wu, Zhengzheng; Yang, Chen

    2016-11-01

    This review systematically addresses the micromachining technologies used for the fabrication of high-performance radio-frequency (RF) passives that can be integrated into low-cost complementary metal-oxide semiconductor (CMOS)-grade (i.e. low-resistivity) silicon wafers. With the development of various kinds of post-CMOS-compatible microelectromechanical systems (MEMS) processes, 3D structural inductors/transformers, variable capacitors, tunable resonators and band-pass/low-pass filters can be compatibly integrated into active integrated circuits to form monolithic RF system-on-chips. By using MEMS processes, including substrate modifying/suspending and LIGA-like metal electroplating, both the highly lossy substrate effect and the resistive loss can be largely eliminated and depressed, thereby meeting the high-performance requirements of telecommunication applications.

  20. Electrowetting in a water droplet with a movable floating substrate

    Science.gov (United States)

    Shahzad, Amir; Masud, A. R.; Song, Jang-Kun

    2016-05-01

    Electrowetting (EW) enables facile manipulation of a liquid droplet on a hydrophobic surface. In this study, manipulation of an electrolyte droplet having a small floating object on it was investigated on a solid hydrophobic substrate under the EW process. Herein, the floating object exhibited a vertical motion under an applied electric field owing to the spreading and contraction of the droplet on its connecting substrates. The field-induced height variation of the floating object was significantly influenced by the thicknesses of the dielectric and hydrophobic materials. A small mass was also placed on the top floating object and its effect on the spreading of the droplet was observed. In this system, the height of the top floating object is precisely controllable under the application of an electric voltage. The proposed system is expected to be highly useful in the design of nano- and micro-oscillatory systems for microengineering.