Sample records for forms potent contact

  1. Method for forming metal contacts

    DOEpatents

    Reddington, Erik; Sutter, Thomas C; Bu, Lujia; Cannon, Alexandra; Habas, Susan E; Curtis, Calvin J; Miedaner, Alexander; Ginley, David S; Van Hest, Marinus Franciscus Antonius Maria

    2013-09-17

    Methods of forming metal contacts with metal inks in the manufacture of photovoltaic devices are disclosed. The metal inks are selectively deposited on semiconductor coatings by inkjet and aerosol apparatus. The composite is heated to selective temperatures where the metal inks burn through the coating to form an electrical contact with the semiconductor. Metal layers are then deposited on the electrical contacts by light induced or light assisted plating.

  2. Access Control Building Access Contact Appointment Form

    E-print Network

    Liu, Taosheng

    ) will be appointed by every Dean/Chair/Head of a department or unit housed in a building having an electronic accessMSU Police Access Control Building Access Contact Appointment Form A Building Access Contact (BAC control system. The Contact is responsible for authorizing access and maintaining the list of authorized

  3. Front contact solar cell with formed emitter

    DOEpatents

    Cousins, Peter John

    2014-11-04

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  4. Front contact solar cell with formed emitter

    DOEpatents

    Cousins, Peter John (Menlo Park, CA)

    2012-07-17

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  5. Contact sensitizer 2,4-dinitrochlorobenzene is a highly potent human TRPA1 agonist.

    PubMed

    Saarnilehto, M; Chapman, H; Savinko, T; Lindstedt, K; Lauerma, A I; Koivisto, A

    2014-10-01

    2,4-Dinitrochlorobenzene (DNCB) is widely used in human clinical studies and in experimental animal studies to evoke allergic contact dermatitis. 2,4-Dinitrochlorobenzene is a potent immunogen capable of inducing contact sensitization in all humans exposed. However, the mechanism by which DNCB evokes such symptoms is presently unknown. TRPA1 is a nonselective cation channel that is expressed in peptidergic sensory neurons and fibroblasts. TRPA1 activation was recently implicated in the pathophysiology of atopic dermatitis especially in transducing cutaneous itch signals. Here, we test the hypothesis that DNCB acts as a TRPA1 agonist and thereby evokes allergic symptoms. We found that DNCB activates human TRPA1 dose dependently in FLIPR experiments with an EC50 of 167 nM, an effect that was fully blocked by selective TRPA1 antagonists Chembridge-5861528 and A-967079. Similarly, DNCB activated nonselective TRPA1 current in patch clamp studies. Neutralization of 3 critical cysteines in TRPA1 resulted in a loss of DNCB agonism. PMID:25041656

  6. Missing Person Inquiry and Confidential Contact Information Form

    E-print Network

    Swaddle, John

    Missing Person Inquiry and Confidential Contact Information Form In accordance with the Higher a student is reported missing, Each student has the option to designate a confidential contact by submitting investigation procedures. However, keeping your confidential contact up-to-date about your whereabouts will help

  7. Contact resistance in organic transistors that use source and drain electrodes formed by soft contact lamination

    E-print Network

    Rogers, John A.

    Contact resistance in organic transistors that use source and drain electrodes formed by soft contact lamination Jana Zaumseil, Kirk W. Baldwin, and John A. Rogersa) Bell Laboratories, Lucent 2003 Soft contact lamination of source/drain electrodes supported by gold-coated high-resolution rubber

  8. Method of forming contacts for a back-contact solar cell

    DOEpatents

    Manning, Jane

    2013-07-23

    Methods of forming contacts for back-contact solar cells are described. In one embodiment, a method includes forming a thin dielectric layer on a substrate, forming a polysilicon layer on the thin dielectric layer, forming and patterning a solid-state p-type dopant source on the polysilicon layer, forming an n-type dopant source layer over exposed regions of the polysilicon layer and over a plurality of regions of the solid-state p-type dopant source, and heating the substrate to provide a plurality of n-type doped polysilicon regions among a plurality of p-type doped polysilicon regions.

  9. Protonated Form: The Potent Form of Potassium-Competitive Acid Blockers

    PubMed Central

    Luo, Hua-Jun; Deng, Wei-Qiao; Zou, Kun

    2014-01-01

    Potassium-competitive acid blockers (P-CABs) are highly safe and active drugs targeting H+,K+-ATPase to cure acid-related gastric diseases. In this study, we for the first time investigate the interaction mechanism between the protonated form of P-CABs and human H+,K+-ATPase using homology modeling, molecular docking, molecular dynamics and binding free energy calculation methods. The results explain why P-CABs have higher activities with higher pKa values or at lower pH. With positive charge, the protonated forms of P-CABs have more competitive advantage to block potassium ion into luminal channel and to bind with H+,K+-ATPase via electrostatic interactions. The binding affinity of the protonated form is more favorable than that of the neutral P-CABs. In particular, Asp139 should be a very important binding site for the protonated form of P-CABs through hydrogen bonds and electrostatic interactions. These findings could promote the rational design of novel P-CABs. PMID:24845980

  10. Organic light-emitting diodes formed by soft contact lamination

    E-print Network

    Rogers, John A.

    Organic light-emitting diodes formed by soft contact lamination Tae-Woo Lee* , Jana Zaumseil, 2003 (received for review July 5, 2003) Although tremendous progress has been made in organic light against an electroluminescent organic. This method relies only on van der Waals interactions to establish

  11. 78 FR 58608 - Proposed Collection; Comment Request for the EFTPS Primary Contact Information Change Form

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-24

    ...Comment Request for the EFTPS Primary Contact Information Change Form AGENCY: Internal...comments concerning the EFTPS Primary Contact Information Change Form. DATES: Written...Washington, DC 20224. FOR FURTHER INFORMATION CONTACT: Requests for additional...

  12. 75 FR 61245 - Proposed Collection; Comment Request for the EFTPS Primary Contact Information Change Form

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-04

    ...Comment Request for the EFTPS Primary Contact Information Change Form AGENCY: Internal...comments concerning the EFTPS Primary Contact Information Change Form. DATES: Written...Washington, DC 20224. FOR FURTHER INFORMATION CONTACT: Requests for additional...

  13. Method of forming contacts for a back-contact solar cell

    DOEpatents

    Manning, Jane

    2014-07-15

    Methods of forming contacts for solar cells are described. In one embodiment, a method includes forming a silicon layer above a substrate, forming and patterning a solid-state p-type dopant source on the silicon layer, forming an n-type dopant source layer over exposed regions of the silicon layer and over a plurality of regions of the solid-state p-type dopant source, and heating the substrate to provide a plurality of n-type doped silicon regions among a plurality of p-type doped silicon regions.

  14. 78 FR 23898 - Notice of Request for a New Information Collection (Accredited Laboratory Contact Update Form)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-23

    ...Annual Contact Update form will also inform the Agency...per year to complete the forms. Respondents: Accredited...techniques, or other forms of information technology...audiotape, etc.) should contact USDA's Target Center...News_&_Events/Email_Subscription/....

  15. 41 CFR 102-194.45 - Who should I contact about Standard and Optional forms?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2012-01-01 false Who should I contact about Standard and Optional forms? ...PROGRAM § 102-194.45 Who should I contact about Standard and Optional forms? For Standard and Optional forms, you should contact the: Standard and Optional Forms...

  16. 41 CFR 102-194.45 - Who should I contact about Standard and Optional forms?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 false Who should I contact about Standard and Optional forms? ...PROGRAM § 102-194.45 Who should I contact about Standard and Optional forms? For Standard and Optional forms, you should contact the: Standard and Optional Forms...

  17. 41 CFR 102-194.45 - Who should I contact about Standard and Optional forms?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 2013-07-01 false Who should I contact about Standard and Optional forms? ...PROGRAM § 102-194.45 Who should I contact about Standard and Optional forms? For Standard and Optional forms, you should contact the: Standard and Optional Forms...

  18. 41 CFR 102-194.45 - Who should I contact about Standard and Optional forms?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 false Who should I contact about Standard and Optional forms? ...PROGRAM § 102-194.45 Who should I contact about Standard and Optional forms? For Standard and Optional forms, you should contact the: Standard and Optional Forms...

  19. Process and structures for fabrication of solar cells with laser ablation steps to form contact holes

    DOEpatents

    Harley, Gabriel; Smith, David D; Dennis, Tim; Waldhauer, Ann; Kim, Taeseok; Cousins, Peter John

    2013-11-19

    Contact holes of solar cells are formed by laser ablation to accomodate various solar cell designs. Use of a laser to form the contact holes is facilitated by replacing films formed on the diffusion regions with a film that has substantially uniform thickness. Contact holes may be formed to deep diffusion regions to increase the laser ablation process margins. The laser configuration may be tailored to form contact holes through dielectric films of varying thickness.

  20. Organic light-emitting diodes formed by soft contact lamination

    PubMed Central

    Lee, Tae-Woo; Zaumseil, Jana; Bao, Zhenan; Hsu, Julia W. P.; Rogers, John A.

    2004-01-01

    Although tremendous progress has been made in organic light-emitting diodes (OLEDs), with few exceptions they are fabricated in the standard way by sequentially depositing active layers and electrodes onto a substrate. Here we describe a different approach for building OLEDs, which is based on physical lamination of thin metal electrodes supported by an elastomeric layer against an electroluminescent organic. This method relies only on van der Waals interactions to establish spatially homogeneous, intimate contacts between the electrodes and the organic. We find that devices fabricated in this manner have better performance than those constructed with standard processing techniques. The lamination approach avoids forms of disruption that can be introduced at the electrode/organic interface by metal evaporation and has a reduced sensitivity to pinhole or partial pinhole defects. In addition, because this form of “soft” contact lamination is intrinsically compatible with the techniques of soft lithography, it is easy to build patterned OLEDs with feature sizes into the nanometer regime. This method provides a new route to OLEDs for applications ranging from high performance displays to storage and lithography systems that rely on subwavelength light sources. PMID:14704283

  1. Contact-spring forming machine for flat conductor cable receptacles

    NASA Technical Reports Server (NTRS)

    Angele, W.; Martineck, H. G.

    1968-01-01

    Machine tool produces beryllium-copper contact springs for FCC /flat conductor cable/ feed-through receptacles. The springs are heat-treated and plated to impart the required electrical contact properties.

  2. Advanced techniques and painless procedures for nonlinear contact analysis and forming simulation via implicit FEM

    NASA Astrophysics Data System (ADS)

    Zhuang, Shoubing

    2013-05-01

    Nonlinear contact analysis including forming simulation via finite element methods has a crucial and practical application in many engineering fields. However, because of high nonlinearity, nonlinear contact analysis still remains as an extremely challenging obstacle for many industrial applications. The implicit finite element scheme is generally more accurate than the explicit finite element scheme, but it has a known challenge of convergence because of complex geometries, large relative motion and rapid contact state change. It might be thought as a very painful process to diagnose the convergence issue of nonlinear contact. Most complicated contact models have a great many contact surfaces, and it is hard work to well define the contact pairs using the common contact definition methods, which either result in hundreds of contact pairs or are time-consuming. This paper presents the advanced techniques of nonlinear contact analysis and forming simulation via the implicit finite element scheme and the penalty method. The calculation of the default automatic contact stiffness is addressed. Furthermore, this paper presents the idea of selection groups to help easily and efficiently define contact pairs for complicated contact analysis, and the corresponding implementation and usage are discussed. Lastly, typical nonlinear contact models and forming models with nonlinear material models are shown in the paper to demonstrate the key presented method and technologies.

  3. Thermal Contact Resistance Estimation: Influence of the Pressure Contact and the Coating Layer during a Hot Forming Process

    NASA Astrophysics Data System (ADS)

    Abdulhay, B.; Bourouga, B.; Dessain, C.

    2011-05-01

    The application of hot stamping in the automotive industry has experienced a fast growth due to the need for higher passive safety and weight reduction. Today, it is absolutely necessary to have reliable and accurate simulation predictions in order to assess the forming feasibility of a part as early as possible during the car design phase. In this paper, an original experimental procedure developed to estimate the thermal conductance at the Part-Tools interfaces during a hot stamping process, is presented. The tools set (punch and die) have been designed to form samples with an omega shape. Two types of material have been stamped: the Usibor 1500P® and the 22MnB5 galvanized steel. The object is to describe correctly the thermal boundary conditions at the Part-Tools interfaces; the adopted procedure consists in estimating accurately the thermal contact resistance TCR at different contact points for different contact pressure values.

  4. Chronic, irritant contact dermatitis: Mechanisms, variables, and differentiation from other forms of contact dermatitis

    SciTech Connect

    Dahl, M.V. (Univ. of Minnesota Medical School, Minneapolis (USA))

    1988-01-01

    Irritant dermatitis is an eczematous reaction to toxic chemicals contacting the skin. The mechanisms by which various chemicals elicit dermatitis are multiple. Strong irritants quickly elicit signs and symptoms of dermatitis, but weak irritants may not. Chronic cumulative exposure to weak irritants can elicit dermatitis which may mimic allergic contact dermatitis and mislead the physician and patient with respect to cause and preventative strategy. The skins of different people vary in susceptibilities to irritation. Susceptibility is also influenced by chemical properties, vehicles, concentrations, amounts applied to the skin surface, surface area, regional variations, length of exposure, method of exposure, age, sex, race, genetic background, environmental factors, hardening, concomitant disease, and the excited skin syndrome as well as treatment. Patch testing can help distinguish between allergens and irritants, but pitfalls may mislead.35 references.

  5. A dimeric form of the HIV-1 antibody 2G12 elicits potent antibody-dependent cellular cytotoxicity

    PubMed Central

    Klein, Joshua S.; Webster, Alexandre; Gnanapragasam, Priyanthi N. P.; Galimidi, Rachel P.; Bjorkman, Pamela J.

    2010-01-01

    Objective Increasing data support a role for antibody-dependent cellular cytotoxicity (ADCC) in controlling HIV-1 infection. We recently isolated a naturally-occurring dimeric form of the anti-HIV-1 antibody 2G12 and found it to be significantly more potent than 2G12 monomer in neutralizing primary virus strains. However, given the unusual structure of dimeric 2G12 with two Fc regions, it was not clear whether 2G12 dimer could bind to the CD16 Fc receptor on ADCC effector cells or trigger ADCC. Here we compared the in vitro ADCC activities of 2G12 monomer and dimer and investigated the effects of including ADCC-enhancing mutations in both forms of 2G12. Methods An in vitro ADCC assay using target cells stably expressing gp160 was developed to evaluate the activities of 2G12 monomer and dimer with and without ADCC-enhancing mutations that increase the CD16-binding affinity of the 2G12 Fc region. Results Both 2G12 monomer and 2G12 dimer elicited ADCC, although the dimer showed increased potency (lower half-maximal concentration [EC50]) in triggering ADCC, thus confirming its ability to bind CD16 and trigger ADCC. The ADCC-enhancing mutations improved the ADCC activity of 2G12 monomer more than 2G12 dimer such that their EC50 values were nearly equal. However, no increase in non-specific ADCC activity was observed using 2G12 IgGs with these mutations. Conclusion Given the likelihood that ADCC plays a role in protecting against initial infection and/or controlling chronic infection, these data suggest 2G12 dimers and/or addition of ADCC-enhancing mutations could augment the prophylactic and/or therapeutic potential of 2G12. PMID:20597163

  6. Observations on the Influence of Tool-Sheet Contact Conditions on an Incremental Forming Process

    NASA Astrophysics Data System (ADS)

    Durante, M.; Formisano, A.; Langella, A.

    2011-08-01

    The influence of tool-sheet contact conditions on features such as surface roughness, forming force, and formability was evaluated for components produced by incremental forming, a highly flexible innovative sheet metal-forming process. Experimental tests were carried out on sheets of AA7075T0 to create two types of component: pyramid frusta (for the evaluation of roughness and force) and cone frusta (for the evaluation of formability). Four different types of tool-sheet contact were analyzed, using two types of tool. From the experimental tests, the influence on the surface finishing and on the trend of the forming forces depending on contact type was revealed. Contact types do not, however, influence sheet formability.

  7. Microsoft Word - App 3-1 Participant Contact Form.doc

    Cancer.gov

    Lung Screening Study Version 3.0 Manual of Operations and Procedures 11/15/00 Appendix 3-1 Lung Screening Study Participant Contact Form Today's Date: |___|___| / |___|___| / | 2 | 0 | | | MONTH DAY YEAR 1. What is your full name?

  8. Method of forming emitters for a back-contact solar cell

    DOEpatents

    Li, Bo; Cousins, Peter J; Smith, David D

    2014-12-16

    Methods of forming emitters for back-contact solar cells are described. In one embodiment, a method includes forming a first solid-state dopant source above a substrate. The first solid-state dopant source includes a plurality of regions separated by gaps. Regions of a second solid-state dopant source are formed above the substrate by printing.

  9. Method or forming emitters for a back-contact solar cell

    DOEpatents

    Li, Bo; Cousins, Peter J.; Smith, David D.

    2014-08-12

    Methods of forming emitters for back-contact solar cells are described. In one embodiment, a method includes forming a first solid-state dopant source above a substrate. The first solid-state dopant source includes a plurality of regions separated by gaps. Regions of a second solid-state dopant source are formed above the substrate by printing.

  10. Gear sound levels with various tooth contact ratios and forms

    NASA Technical Reports Server (NTRS)

    Lenski, Joseph W., Jr.; Spencer, Robert H.; Drago, Raymond J.; Valco, Mark J.; Oswald, Fred B.

    1993-01-01

    The real noise reduction benefits which may be obtained through the use of one gear tooth form as compared to another is an important design parameter for any geared system, especially for helicopters in which both weight and reliability are very important factors. The design and testing of nine sets of gears which are as identical as possible except for their basic tooth geometry are described. Noise measurements were made at various combinations of load and speed for each gear set so that direct comparisons could be made. The resultant data was analyzed so that valid conclusions could be drawn and interpreted for design use.

  11. Ion Channel-Forming Alamethicin Is a Potent Elicitor of Volatile Biosynthesis and Tendril Coiling. Cross Talk between Jasmonate and Salicylate Signaling in Lima Bean

    Microsoft Academic Search

    Jurgen Engelberth; Thomas Koch; Gode Schuler; Nadine Bachmann; Jana Rechtenbach; Wilhelm Boland

    2001-01-01

    Alamethicin (ALA), a voltage-gated, ion channel-forming peptide mixture from Trichoderma viride, is a potent elicitor of the biosynthesis of volatile compounds in lima bean (Phaseolus lunatus). Unlike elicitation with jasmonic acid or herbivore damage, the blend of substances emitted comprises only the two homoterpenes, 4,11-dimethylnona-1,3,7-triene and 4,8,12-trimethyltrideca-1,3,7,11-tetraene, and methyl salicylate. Inhibition of octadecanoid signaling by aristolochic acid and phenidone as

  12. Disruption of Contact Lens–Associated Pseudomonas aeruginosa Biofilms Formed in the Presence of Neutrophils

    PubMed Central

    Parks, Quinn M.; Young, Robert L.; Kret, Jennifer; Poch, Katie R.; Malcolm, Kenneth C.; Nichols, David P.; Nichols, Michelle; Zhu, Meifang; Cavanagh, H. Dwight; Nick, Jerry A.

    2011-01-01

    Purpose. To evaluate the capacity of neutrophils to enhance biofilm formation on contact lenses by an infectious Pseudomonas aeruginosa (PA) corneal isolate. Agents that target F-actin and DNA were tested as a therapeutic strategy for disrupting biofilms formed in the setting of neutrophils in vitro and for limiting the infectious bioburden in vivo. Methods. Biofilm formation by infectious PA strain 6294 was assessed in the presence of neutrophils on a static biofilm plate and on unworn etafilcon A soft contact lenses. A d-isomer of poly(aspartic acid) was used alone and with DNase to reduce biofilm formation on test contact lenses. The gentamicin survival assay was used to determine the effectiveness of the test compound in reducing subsequent intracellular bacterial load in the corneal epithelium in a contact lens infection model in the rabbit. Results. In a static reactor and on hydrogel lenses, PA biofilm density was enhanced 30-fold at 24 hours in the presence of neutrophils (P < 0.0001). The combination of DNase and anionic poly(aspartic acid) reduced the PA biofilms formed in the presence of activated neutrophils by 79.2% on hydrogel contact lenses (P < 0.001). An identical treatment resulted in a 41% reduction in internalized PA in the rabbit corneal epithelium after 24 hours (P = 0.03). Conclusions. These results demonstrate that PA can exploit the presence of neutrophils to form biofilm on contact lenses within a short time. Incorporation of F-actin and DNA represent a mechanism for neutrophil-induced biofilm enhancement and are targets for available agents to disrupt pathogenic biofilms formed on contact lenses and as a treatment for established corneal infections. PMID:21245396

  13. Contacts

    Cancer.gov

    Contacts Questions regarding responsiveness of the proposed studies to the BIQSFP should be directed to one of the following NCI Program Staff: For CTEP: Margaret M. Mooney, MD Chief Clinical Investigations Branch National Cancer Institute 9609 Medical

  14. THE HISTORY OF STANDARD OIL/EXXONMOBIL IN BATON ROUGE Oral History Interviewee Contact Survey Form

    E-print Network

    Harms, Kyle E.

    THE HISTORY OF STANDARD OIL/EXXONMOBIL IN BATON ROUGE Oral History Interviewee Contact Survey Form LSU Libraries Special Collections Williams Center for Oral History If you think that you location; T. Harry Williams Center for Oral History: ATTN: Staff LSU Libraries Special Collections Agnes

  15. UM Computer Science 2014-2015 Parent/Guardian Consent & Contact Form

    E-print Network

    Chu, Xi

    UM Computer Science 2014-2015 Parent/Guardian Consent & Contact Form Print Child's Name: __________ I/we give our son/daughter permission to participate in the UM Computer Science workshop to the provision of any necessary emergency treatment to my son/daughter during the program by UM Computer Science

  16. Process for forming pure silver ohmic contacts to N- and P-type gallium arsenide materials

    DOEpatents

    Hogan, S.J.

    1983-03-13

    Disclosed is an improved process for manufacturing gallium arsenide semiconductor devices having as its components a n-type gallium arsenide substrate layer and a p-type gallium arsenide diffused layer. The improved process comprises forming a pure silver ohmic contact to both the diffuse layer and the substrate layer wherein the n-type layer comprises a substantially low doping carrier concentration.

  17. Contacting your elected representatives is easier than you might think. You can call and talk to a staffer or fill out a contact form using their website. You can find your Representative's contact info here. You

    E-print Network

    Seager, Sara

    Contacting your elected representatives is easier than you might think. You can call and talk to a staffer or fill out a contact form using their website. You can find your Representative's contact info&D plays a key role in driving U.S. innovation, productivity, and overall economic growth, the impacts

  18. Front contact solar cell with formed electrically conducting layers on the front side and backside

    DOEpatents

    Cousins, Peter John

    2012-06-26

    A bipolar solar cell includes a backside junction formed by a silicon substrate and a first doped layer of a first dopant type on the backside of the solar cell. A second doped layer of a second dopant type makes an electrical connection to the substrate from the front side of the solar cell. A first metal contact of a first electrical polarity electrically connects to the first doped layer on the backside of the solar cell, and a second metal contact of a second electrical polarity electrically connects to the second doped layer on the front side of the solar cell. An external electrical circuit may be electrically connected to the first and second metal contacts to be powered by the solar cell.

  19. Effects of varying machine stiffness and contact area in UltraForm Finishing

    NASA Astrophysics Data System (ADS)

    Briggs, Dennis E.; Echaves, Samantha; Pidgeon, Brendan; Travis, Nathan; Ellis, Jonathan D.

    2013-09-01

    UltraForm Finishing (UFF) is a deterministic, subaperture, computer numerically controlled, grinding and polishing platform designed by OptiPro Systems. UFF is used to grind and polish a variety optics from simple spherical to fully freeform, and numerous materials from glasses to optical ceramics. The UFF system consists of an abrasive belt around a compliant wheel that rotates and contacts the part to remove material. This work aims to measure the stiffness variations in the system and how it can affect material removal rates. The stiffness of the entire system is evaluated using a triaxial load cell to measure forces and a capacitance sensor to measure deviations in height. Because the wheel is conformal and elastic, the shapes of contact areas are also of interest. For the scope of this work, the shape of the contact area is estimated via removal spot. The measured forces and removal spot area are directly related to material removal rate through Preston's equation. Using our current testing apparatus, we will demonstrate stiffness measurements and contact areas for a single UFF belt during different states of its lifecycle and assess the material removal function from spot diagrams as a function of wear. This investigation will ultimately allow us to make better estimates of Preston's coefficient and develop spot-morphing models in an effort to more accurately predict instantaneous material removal functions throughout the lifetime of a belt.

  20. Self-assembled nanoparticle deposits formed at the contact line of evaporating micrometer-size droplets

    NASA Astrophysics Data System (ADS)

    Govor, Leonid V.; Reiter, Günter; Parisi, Jürgen; Bauer, Gottfried H.

    2004-06-01

    We report on the formation of self-assembled rings of Co Pt3 nanoparticles (ring diameter ranging from 0.6 to 1.5 ?m , particle diameter 6 nm ) formed in an evaporating thin film. The latter was achieved on the surface of water by spreading a binary mixture composed of two solutions: nitrocellulose dissolved in amyl acetate and Co Pt3 particles stabilized by hexadecylamine dissolved in hexane. The self-assembly process of the nanometer-sized particles into micrometer-sized rings results from phase separation in a thin film of the mixed solutions, leading to a bilayer, and the subsequent decomposition during solvent evaporation of the top hexadecylamine-rich layer into droplets. Finally, the evaporation of the remaining solvent from these droplets gives rise to a retraction of their contact line. The Co Pt3 particles located at the contact line follow its motion and self-assemble along this line.

  1. Complex formation in aqueous solution and in the solid state of the potent insulin-enhancing V(IV)O2+ compounds formed by picolinate and quinolinate derivatives.

    PubMed

    Lodyga-Chruscinska, Elzbieta; Micera, Giovanni; Garribba, Eugenio

    2011-02-01

    The complexation of V(IV)O(2+) ion with 10 picolinate and quinolinate derivatives, provided with the donor set (N, COO(-)), was studied in aqueous solution and in the solid state through the combined application of potentiometric (pH-titrations), spectroscopic (EPR, UV/vis and IR spectroscopy), and computational (density functional theory (DFT) calculations) methods. Such derivatives, that form potent insulin-enhancing V(IV)O(2+) compounds, are picolinic (picH), 6-methylpicolinic (6-mepicH), 3-methylpicolinic (3-mepicH), 5-butylpicolinic or fusaric (fusarH), 6-methyl-2,3-pyridindicarboxylic (6-me-2,3-pdcH(2)), 2-pyridylacetic (2-pyacH), 2-quinolinecarboxylic or quinaldic (quinH), 4-hydroxyquinoline-2-carboxylic or kynurenic (kynurH), 1-isoquinolinecarboxylic (1-iqcH) and 3-isoquinolinecarboxylic (3-iqcH) acid. On the basis of the potentiometric, spectroscopic, and DFT results, they were divided into the classes A, B, and C. The ligands belonging to class A (3-mepicH, 1-iqcH, 2-pyacH) form square pyramidal complexes in aqueous solution and in the solid state, and those belonging to class B (picH, fusarH, 3-iqcH) form cis-octahedral species, in which the two ligands adopt an (equatorial-equatorial) and an (equatorial-axial) arrangement and one water molecule occupies an equatorial site in cis position with respect to the V?O bond. Class C ligands (6-mepicH, 6-me-2,3-pdcH(2), quinH, kynurH) yield bis chelated species, that in water are in equilibrium between the square pyramidal and trans-octahedral form, where both the ligand molecules adopt an (equatorial-equatorial) arrangement and one water is in trans position with respect to the V?O group. The trans-octahedral compounds are characterized by an anomalous electron paramagnetic resonance (EPR) response, with A(z) value being reduced by about 10% with respect to the prediction of the "additivity rule". DFT methods allow to calculate the structure, (51)V hyperfine coupling constant (A(z)), the stretching frequency of V?O bond (?(V?O)), the relative stability in aqueous solution, and the electronic structure and molecular orbital composition of bis chelated complexes. The results were used to explain the biotransformation of these potent insulin-enhancing compounds in blood serum. PMID:21226475

  2. H-1B Visa Request Form (Contact & submit to PeiLei Chow, CBMG, 1119 Microbiology, pchow@umd.edu)

    E-print Network

    Gruner, Daniel S.

    H-1B Visa Request Form (Contact & submit to PeiLei Chow, CBMG, 1119 Microbiology, pchow@umd.edu) H1 Microbiology 3. Supporting letter on Univ. dept. letterhead 4. FRS #______________ for fees P.I. Name

  3. Specific Contact Resistance Measurement of Screen-Printed Ag Metal Contacts Formed on Heavily Doped Emitter Region in Multicrystalline Silicon Solar Cells

    NASA Astrophysics Data System (ADS)

    Vinod, P. Narayanan

    2013-10-01

    Multicrystalline silicon (mc-Si) wafers are widely used to develop low-cost high-efficiency screen-printed solar cells. In this study, the electrical properties of screen-printed Ag metal contacts formed on heavily doped emitter region in mc-Si solar cells have been investigated. Sintering of the screen-printed metal contacts was performed by a co-firing step at 725°C in air ambient followed by low-temperature annealing at 450°C for 15 min. Measurement of the specific contact resistance ( ? c) of the Ag contacts was performed by the three-point probe method, showing a best value of ? c = 1.02 × 10-4 ? cm2 obtained for the Ag contacts. This value is considered as a good figure of merit for screen-printed Ag electrodes formed on a doped mc-Si surface. The plot of ? c versus the inverse of the square root of the surface doping level ( N {s/-½}) follows a linear relationship for impurity doping levels N s ? 1019 atoms/cm3. The power losses due to current traveling through various resistive components of finished solar cells were calculated by using standard expressions. Cross-sectional scanning electron microscopy (SEM) views of the Ag metal and doped mc-Si region show that the Ag metal is firmly coalesced with the doped mc-Si surface upon sintering at an optimum firing temperature of 725°C.

  4. Ethanol Extract of Peanut Sprout Exhibits a Potent Anti-Inflammatory Activity in Both an Oxazolone-Induced Contact Dermatitis Mouse Model and Compound 48/80-Treated HaCaT Cells

    PubMed Central

    Choi, Da-In; Choi, Jee-Young; Kim, Young Jee; Lee, Jee-Bum; Kim, Sun-Ouck; Shin, Hyong-Taek

    2015-01-01

    Background We developed an ethanol extract of peanut sprouts (EPS), a peanut sprout-derived natural product, which contains a high level of trans-resveratrol (176.75 µg/ml) and was shown to have potent antioxidant activity. Objective We evaluated the potential anti-inflammatory activity of EPS by measuring its antioxidant potential in skin. Methods The anti-inflammatory activity of EPS was tested using two models of skin inflammation: oxazolone (OX)-induced contact dermatitis in mice and compound 48/80-treated HaCaT cells. As biomarkers of skin inflammation, cyclooxygenase-2 (COX-2) and nerve growth factor (NGF) levels were measured. Results OX-induced contact dermatitis was suppressed markedly in mice that were treated with an ointment containing 5% EPS as evidenced by a decrease in the extent of scaling and thickening (p<0.05) and supported by a histological study. COX-2 (messenger RNA [mRNA] and protein) and NGF (mRNA) levels, which were upregulated in the skin of OX-treated mice, were suppressed markedly in the skin of OX+EPS-treated mice. Consistent with this, compound 48/80-induced expression of COX-2 (mRNA and protein) and NGF (mRNA) in HaCaT cells were suppressed by EPS treatment in a dose-dependent manner. As an inhibitor of NF-?B, I?B protein levels were dose-dependently upregulated by EPS. Fluorescence-activated cell sorting (FACS) analysis revealed that EPS scavenged compound 48/80-induced reactive oxygen species (ROS) in HaCaT cells. Conclusion EPS exerts a potent anti-inflammatory activity via its anti-oxidant activity in both mouse skin and compound 48/80-treated HaCaT cells in vitro. Compound 48/80-treated HaCaT cells are a useful new in vitro model of skin inflammation.

  5. Non-contact high precision measurement of surface form tolerances and central thickness for optical elements

    NASA Astrophysics Data System (ADS)

    Lou, Ying

    2010-10-01

    The traditional contact measuring methods could not satisfy the current optical elements measuring requirements. Noncontact high precision measuring theory, principle and instrument of the surface form tolerances and central thickness for optical elements were studied in the paper. In comparison with other types of interferometers, such as Twyman-Green and Mach-Zehnder, a Fizeau interferometer has the advantages of having fewer optical components, greater accuracy, and is easier to use. Some relations among the 3/A(B/C), POWER/PV and N/?N were studied. The PV with POWER removed can be the reference number of ?N. The chromatic longitudinal aberration of a special optical probe can be used for non-contanct central thickness measurement.

  6. Nanoscale electro-structural characterisation of ohmic contacts formed on p-type implanted 4H-SiC

    NASA Astrophysics Data System (ADS)

    Frazzetto, Alessia; Giannazzo, Filippo; Lo Nigro, Raffaella; di Franco, Salvatore; Bongiorno, Corrado; Saggio, Mario; Zanetti, Edoardo; Raineri, Vito; Roccaforte, Fabrizio

    2011-12-01

    This work reports a nanoscale electro-structural characterisation of Ti/Al ohmic contacts formed on p-type Al-implanted silicon carbide (4H-SiC). The morphological and the electrical properties of the Al-implanted layer, annealed at 1700°C with or without a protective capping layer, and of the ohmic contacts were studied using atomic force microscopy [AFM], transmission line model measurements and local current measurements performed with conductive AFM. The characteristics of the contacts were significantly affected by the roughness of the underlying SiC. In particular, the surface roughness of the Al-implanted SiC regions annealed at 1700°C could be strongly reduced using a protective carbon capping layer during annealing. This latter resulted in an improved surface morphology and specific contact resistance of the Ti/Al ohmic contacts formed on these regions. The microstructure of the contacts was monitored by X-ray diffraction analysis and a cross-sectional transmission electron microscopy, and correlated with the electrical results.

  7. Nanoscale electro-structural characterisation of ohmic contacts formed on p-type implanted 4H-SiC.

    PubMed

    Frazzetto, Alessia; Giannazzo, Filippo; Lo Nigro, Raffaella; Di Franco, Salvatore; Bongiorno, Corrado; Saggio, Mario; Zanetti, Edoardo; Raineri, Vito; Roccaforte, Fabrizio

    2011-01-01

    This work reports a nanoscale electro-structural characterisation of Ti/Al ohmic contacts formed on p-type Al-implanted silicon carbide (4H-SiC). The morphological and the electrical properties of the Al-implanted layer, annealed at 1700°C with or without a protective capping layer, and of the ohmic contacts were studied using atomic force microscopy [AFM], transmission line model measurements and local current measurements performed with conductive AFM.The characteristics of the contacts were significantly affected by the roughness of the underlying SiC. In particular, the surface roughness of the Al-implanted SiC regions annealed at 1700°C could be strongly reduced using a protective carbon capping layer during annealing. This latter resulted in an improved surface morphology and specific contact resistance of the Ti/Al ohmic contacts formed on these regions. The microstructure of the contacts was monitored by X-ray diffraction analysis and a cross-sectional transmission electron microscopy, and correlated with the electrical results. PMID:21711667

  8. Laser method for forming low-resistance ohmic contacts on semiconducting oxides

    DOEpatents

    Narayan, Jagdish (Knoxville, TN)

    1981-01-01

    This invention is a new method for the formation of high-quality ohmic contacts on wide-band-gap semiconducting oxides. As exemplified by the formation of an ohmic contact on n-type BaTiO.sub.3 containing a p-n junction, the invention entails depositing a film of a metallic electroding material on the BaTiO.sub.3 surface and irradiating the film with a Q-switched laser pulse effecting complete melting of the film and localized melting of the surface layer of oxide immediately underlying the film. The resulting solidified metallic contact is ohmic, has unusually low contact resistance, and is thermally stable, even at elevated temperatures. The contact does not require cleaning before attachment of any suitable electrical lead. This method is safe, rapid, reproducible, and relatively inexpensive.

  9. Method for forming low-resistance ohmic contacts on semiconducting oxides

    DOEpatents

    Narayan, J.

    1979-10-01

    The invention provides a new method for the formation of high-quality ohmic contacts on wide-band-gap semiconducting oxides. As exemplified by the formation of an ohmic contact on n-type BaTiO/sub 3/ containing a p-n junction, the invention entails depositing a film of a metallic electroding material on the BaTiO/sub 3/ surface and irradiating the film with a Q-switched laser pulse effecting complete melting of the film and localized melting of the surface layer of oxide immediately underlying the film. The resulting solidified metallic contact is ohmic, has unusually low contact resistance, and is thermally stable, even at elevated temmperatures. The contact does not require cleaning before attachment of any suitable electrical lead. This method is safe, rapid, reproducible, and relatively inexpensive.

  10. Edge contacts of graphene formed by using a controlled plasma treatment.

    PubMed

    Yue, D W; Ra, C H; Liu, X C; Lee, D Y; Yoo, W J

    2015-01-14

    Despite the fact that the outstanding properties of graphene are well known, the electrical performance of the material is limited by the contact resistance at the metal-graphene interface. In this study, we demonstrate the formation of "edge-contacted" graphene through the use of a controlled plasma processing technique that generates a bond between the graphene edge and the contact metal. This technique controls the edge structure of the bond and significantly reduces the contact resistance. This simple approach requires no additional post-processing and has been proven to be very effective. In addition, controlled pre-plasma processing was applied in order to produce CVD-graphene field effect transistors with an enhanced adhesion and improved carrier mobility. The contact resistance attained by using pre-plasma processing was 270 ? ?m, which is a decrease of 77%. PMID:25437108

  11. Edge contacts of graphene formed by using a controlled plasma treatment

    NASA Astrophysics Data System (ADS)

    Yue, D. W.; Ra, C. H.; Liu, X. C.; Lee, D. Y.; Yoo, W. J.

    2014-12-01

    Despite the fact that the outstanding properties of graphene are well known, the electrical performance of the material is limited by the contact resistance at the metal-graphene interface. In this study, we demonstrate the formation of ``edge-contacted'' graphene through the use of a controlled plasma processing technique that generates a bond between the graphene edge and the contact metal. This technique controls the edge structure of the bond and significantly reduces the contact resistance. This simple approach requires no additional post-processing and has been proven to be very effective. In addition, controlled pre-plasma processing was applied in order to produce CVD-graphene field effect transistors with an enhanced adhesion and improved carrier mobility. The contact resistance attained by using pre-plasma processing was 270 ? ?m, which is a decrease of 77%.Despite the fact that the outstanding properties of graphene are well known, the electrical performance of the material is limited by the contact resistance at the metal-graphene interface. In this study, we demonstrate the formation of ``edge-contacted'' graphene through the use of a controlled plasma processing technique that generates a bond between the graphene edge and the contact metal. This technique controls the edge structure of the bond and significantly reduces the contact resistance. This simple approach requires no additional post-processing and has been proven to be very effective. In addition, controlled pre-plasma processing was applied in order to produce CVD-graphene field effect transistors with an enhanced adhesion and improved carrier mobility. The contact resistance attained by using pre-plasma processing was 270 ? ?m, which is a decrease of 77%. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05725b

  12. Pt/Ti/n-InP nonalloyed ohmic contacts formed by rapid thermal processing

    NASA Astrophysics Data System (ADS)

    Katz, A.; Weir, B. E.; Chu, S. N. G.; Thomas, P. M.; Soler, M.; Boone, T.; Dautremont-Smith, W. C.

    1990-04-01

    Low resistance nonalloyed ohmic contacts of e-gun evaporated Pt/Ti to S doped n-InP 5×1017, 1×1018, and 5×1018 cm-3 have been fabricated by rapid thermal processing. The contacts to the lower doped substrates (5×1017 and 1×1018 cm-3) were rectifying as-deposited as well as after heat treatment at temperatures lower than 350 °C. Higher processing temperatures stimulated the Schottky to ohmic contact conversion with minimum specific contact resistance of 1.5×10-5 and 5×10-6 ? cm2, respectively, as a result of rapid thermal processing at 450 °C for 30 s. Heating at a temperature of 550 °C again yielded a Schottky contact. The contact to the 5×1018 cm-3 InP was ohmic as deposited with a specific contact resistance value of 1.1×10-4 ? cm2. Supplying heat treatment to the contact caused a decrease of the specific contact resistance to a minimum of 8×10-7 ? cm2 as a result of rapid thermal processing at 450 °C for 30 s. In all cases, this heat treatment caused a limited interfacial reactions between the Ti and the InP, and resulted in an almost abrupt interface. Heating at temperatures higher than 500 °C resulted in an interfacial intermixing and a mutual migration and reaction of the Ti and the semiconductor elements. The Pt/Ti bilayer structure was highly tensile as deposited (5×109 dyn cm-2) and became stress-free as a result of the interfacial reactions which took place while heating the samples to temperature of 400 °C or higher.

  13. A truncated form of CKbeta8-1 is a potent agonist for human formyl peptide-receptor-like 1 receptor.

    PubMed

    Elagoz, Aram; Henderson, Duncan; Babu, Poda Suresh; Salter, Sylvia; Grahames, Caroline; Bowers, Lorna; Roy, Marie-Odile; Laplante, Patricia; Grazzini, Eric; Ahmad, Sultan; Lembo, Paola M C

    2004-01-01

    1. Human formyl peptide-receptor-like-1 (FPRL-1) is a promiscuous G protein-coupled receptor (GPCR), and belongs to a chemoattractant receptor family protein. This receptor has been reported to interact with various host-derived peptides and lipids involved in inflammatory responses. We described here, a novel role for FPRL-1 as a high-affinity beta-chemokine receptor for an N-terminally truncated form of the CKbeta8 (CCL23/MPIF-1) splice variant CKbeta8-1 (22-137 aa). 2. RT-PCR analysis of mRNA derived from human tissues and cells revealed a predominant expression of FPRL-1 in inflammatory cells, particularly in neutrophils. 3. Intracellular calcium mobilisation assay, used as screening tool, in recombinant Chinese hamster ovary (CHO-K1) and human embryonic kidney (HEK293s) cells coexpressing FPRL-1 and Galpha(16), demonstrated FPRL-1 is a functional high-affinity receptor for CKbeta8-1 (46-137 aa, sCKbeta8-1), with pEC(50) values of 9.13 and 8.85, respectively. 4. The FPRL-1 activation in CHO-K1 cells is mediated by Galpha(i)/Galpha(o) proteins, as assessed by pertussis toxin sensitivity and inhibition of forskolin-induced cyclic AMP accumulation. 5. Binding experiments were performed with a radio-iodinated synthetic peptide, [(125-)I]-WKYMVm, a known potent FPRL-1 agonist. CHO-K1 cell membranes expressing FPRL-1 bound [(125-)I]-WKYMVm with a K(d) value of 9.34. Many known FPRL-1 agonists were tested and sCKbeta8-1 was the most effective nonsynthetic ligand in displacing the radiolabelled agonist, with a pIC(50) of 7.97. 6. The functional significance of sCKbeta8-1 interaction with FPRL-1 was further demonstrated by the activation of polymorphonuclear leukocytes (PMNs) calcium mobilisation and chemotaxis. These interactions were shown to be via FPRL-1 by specific blockade of PMNs activation in the presence of an FPRL-1 antibody. PMID:14662730

  14. Rational Design of a Potent, Long-Lasting Form of Interferon:  A 40 kDa Branched Polyethylene Glycol-Conjugated Interferon ?-2a for the Treatment of Hepatitis C

    Microsoft Academic Search

    Pascal Bailon; Alicia Palleroni; Carol A. Schaffer; Cheryl L. Spence; Wen-Jian Fung; Jill E. Porter; George K. Ehrlich; Wen Pan; Zhi-Xin Xu; Marlene W. Modi; Adrienne Farid; Wolfgang Berthold; Mary Graves

    2001-01-01

    A potent, long-lasting form of interferon R-2a mono-pegylated with a 40 kilodalton branched poly- (ethylene glycol) was designed, synthesized, and characterized. Mono-pegylated interferon R-2a was comprised of four major positional isomers involving Lys31, Lys121, Lys131, and Lys134 of interferon. The in vitro anti-viral activity of pegylated interferon R-2a was found to be only 7% of the original activity. In contrast,

  15. New surface contacts formed upon reductive lysine methylation: Improving the probability of protein crystallization

    PubMed Central

    Sledz, Pawel; Zheng, Heping; Murzyn, Krzysztof; Chruszcz, Maksymilian; Zimmerman, Matthew D; Chordia, Mahendra D; Joachimiak, Andrzej; Minor, Wladek

    2010-01-01

    Surface lysine methylation (SLM) is a technique for improving the rate of success of protein crystallization by chemically methylating lysine residues. The exact mechanism by which SLM enhances crystallization is still not clear. To study these mechanisms, and to analyze the conditions where SLM will provide the optimal benefits for rescuing failed crystallization experiments, we compared 40 protein structures containing N,N-dimethyl-lysine (dmLys) to a nonredundant set of 18,972 nonmethylated structures from the PDB. By measuring the relative frequency of intermolecular contacts (where contacts are defined as interactions between the residues in proximity with a distance of 3.5 Å or less) of basic residues in the methylated versus nonmethylated sets, dmLys-Glu contacts are seen more frequently than Lys-Glu contacts. Based on observation of the 10 proteins with both native and methylated structures, we propose that the increased rate of contact for dmLys-Glu is due to both a slight increase in the number of amine-carboxyl H-bonds and to the formation of methyl C–H···O interactions. By comparing the relative contact frequencies of dmLys with other residues, the mechanism by which methylation of lysines improves the formation of crystal contacts appears to be similar to that of Lys to Arg mutation. Moreover, analysis of methylated structures with the surface entropy reduction (SER) prediction server suggests that in many cases SLM of predicted SER sites may contribute to improved crystallization. Thus, tools that analyze protein sequences and mark residues for SER mutation may identify proteins with good candidate sites for SLM. PMID:20506323

  16. Two cases with nickel-induced oral mucosal hyperplasia: a rare clinical form of allergic contact stomatitis?

    PubMed

    Özkaya, Esen; Babuna, Goncagül

    2011-01-01

    Allergic contact stomatitis (ACS) can occur with variable clinical presentations such as erythematous, erosive, and lichenoid forms. Burning mouth symptoms may also be a result of allergic contact stomatitis. Additionally, gingival hyperplasia has been reported in exceptional cases of ACS caused by dental metals. Here, two rare cases are presented of nickel-induced oral mucosal hyperplasia with gingival and upper palatal involvement from metal-porcelain crowns and metal-acrylic upper denture, respectively. In both cases the diagnosis was made on the basis of the positive patch test results to nickel sulfate and the regression of the lesions after removing the nickel containing dental materials. Nickel-induced ACS should be borne in mind in every case of oral mucosal hyperplasia appearing after dental procedures, especially in the presence of previous allergies and sensitization risks such as ear piercing. It might be further suggested to include this variant within the clinical forms of ACS. PMID:21426878

  17. Ohmic contacts to n-GaN formed by ion-implanted Si into p-GaN

    NASA Astrophysics Data System (ADS)

    Bao, Xichang; Xu, Jintong; Zhang, Wenjing; Wang, Ling; Chu, Kaihui; Li, Chao; Li, Xiangyang

    2009-07-01

    In this paper, we report the ohmic contact to n-GaN fabricated by implanting silicon into Mg-doped GaN using an alloy of Ti/Al/Ti/Au metallization. The used materials were grown on (001) sapphire substrates by metal-organic chemical-vapor deposition (MOCVD). The layer structure was comprised of a GaN buffer layer and followed by a 2 ?m thickness Mg-doped GaN (Na=5×1017cm-3) and then double silicon implantation was performed in order to convert p-type GaN into n-type GaN films. The as-implanted samples were then thermal annealed at 1150 °C for 5 min in N2 ambient. The carrier concentration and Hall mobility were 3.13×1018 cm3 and 112 cm2/ (VÂ.s) measured by Hall method. Multilayer electrode of Ti (50 nm)/Al (50 nm)/Ti (30 nm)/Au (30 nm) was deposited on n-GaN using an electron-beam evaporation and contacts were formed by a N2 annealing technique ranging from 600 to 900 °C. After annealing lower than 700 °C, the contacts exhibited a rectifying behavior and became ohmic contact only after high temperature processes (>=700 °C). Specific contact resistance was as low as 9.58×10-4 ?Â.cm2 after annealing at 800 °C for 60 seconds. While annealing temperature is higher than 800 °C, the specific contact resistance becomes worse. This phenomenon is caused by the surface morphology degradation.

  18. Auger analysis of films formed on metals in sliding contact with halogenated polymers

    NASA Technical Reports Server (NTRS)

    Pepper, S. V.

    1974-01-01

    The use of Auger electron spectroscopy (AES) to search for transferred polymer must contend with the fact that there has been no published work on Auger analysis of polymers. Since this is a new area for AES, the Auger spectra of polymers and of halogenated polymers in particular is discussed. It is shown that the Auger spectra of halogenated polymers have certain characteristics that permit an assessment of whether a polymeric transfer film has been established by sliding contact. The discussion is general and the concepts should be useful in considering the Auger analysis of any polymer. The polymers chosen for this study are the halogenated polymers polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), and polychlorotrifluorethylene (PCTFE).

  19. LANSCE Training Office Process Improvement Form You recently contacted our training service department. We want to assure that you're satisfied with

    E-print Network

    LANSCE Training Office Process Improvement Form You recently contacted our training service feedback will be used to improve our service. How did you contact the TA-53 Training office for training Proctoring Training Report/Status Other______________ The Training Office handled my request quickly

  20. Experiments and simulations show how long-range contacts can form in expanded unfolded proteins with negligible secondary structure

    PubMed Central

    Meng, Wenli; Lyle, Nicholas; Luan, Bowu; Raleigh, Daniel P.; Pappu, Rohit V.

    2013-01-01

    The sizes of unfolded proteins under highly denaturing conditions scale as N0.59 with chain length. This suggests that denaturing conditions mimic good solvents, whereby the preference for favorable chain–solvent interactions causes intrachain interactions to be repulsive, on average. Beyond this generic inference, the broader implications of N0.59 scaling for quantitative descriptions of denatured state ensembles (DSEs) remain unresolved. Of particular interest is the degree to which N0.59 scaling can simultaneously accommodate intrachain attractions and detectable long-range contacts. Here we present data showing that the DSE of the N-terminal domain of the L9 (NTL9) ribosomal protein in 8.3 M urea lacks detectable secondary structure and forms expanded conformations in accord with the expected N0.59 scaling behavior. Paramagnetic relaxation enhancements, however, indicate the presence of detectable long-range contacts in the denatured-state ensemble of NTL9. To explain these observations we used atomistic thermal unfolding simulations to identify ensembles whose properties are consistent with all of the experimental observations, thus serving as useful proxies for the DSE of NTL9 in 8.3 M urea. Analysis of these ensembles shows that residual attractions are present under mimics of good solvent conditions, and for NTL9 they result from low-likelihood, medium/long-range contacts between hydrophobic residues. Our analysis provides a quantitative framework for the simultaneous observation of N0.59 scaling and low-likelihood long-range contacts for the DSE of NTL9. We propose that such low-likelihood intramolecular hydrophobic clusters might be a generic feature of DSEs that play a gatekeeping role to protect against aggregation during protein folding. PMID:23341588

  1. Oxidized eicosapentaenoic acids more potently reduce LXR?-induced cellular triacylglycerol via suppression of SREBP-1c, PGC-1? and GPA than its intact form

    PubMed Central

    2013-01-01

    Dietary polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA), improve lipid metabolism and contribute to the prevention of vascular diseases such as atherosclerosis. However, EPA in the diet is easily oxidized at room temperature and several types of oxidized EPA (OEPA) derivatives are generated. To compare the efficiencies of OEPAs on lipid metabolism with EPA, human hepatocellular liver carcinoma cell line (HepG2) was treated with EPA or OEPAs and their effects on lipid metabolism related genes were studied. OEPAs more potently suppressed the expression of sterol-responsive element-binding protein (SREBP)-1c, a major transcription factor that activates the expression of lipogenic genes, and its downstream target genes than did EPA under conditions of lipid synthesis enhanced by T0901317, a synthetic liver X receptor (LXR) agonist. Furthermore, PGC-1?, a coactivator of both LXR? and SREBP-1, was markedly down-regulated by OEPAs compared with EPA. The treatment of OEPAs also significantly down-regulated the expression of glycerol-3-phosphate acyltransferase (GPA), the initiating enzyme in triacylglycerol (TG) synthesis, more than EPA. Therefore, the advantageous effects of OEPAs on cardiovascular diseases might be due to their SREBP-1c, PGC-1? and GPA mediated ameliorating effects. PMID:23680128

  2. Charge and discharge characteristics of a direct contact latent thermal energy storage unit using form-stable high-density polyethylene

    Microsoft Academic Search

    Y. Abe; M. Kamimoto; K. Kanari; T. Ozawa; R. Sakamoto; Y. Takahushi

    1984-01-01

    For solar thermal energy utilization in relatively low temperatures, a lab-scale direct contact, latent thermal energy storage unit using a form-stable high-density polyethylene (HDPE) was developed. The phase change material (PCM), the form-stable HDPE, does not fluidize nor adhere even after melting, and this particular property permits a direct contact heat transfer between the PCM and a heat transfer fluid

  3. Self-formed copper oxide contact interlayer for high-performance oxide thin film transistors

    SciTech Connect

    Gao, Xu, E-mail: GAO.Xu@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp; Aikawa, Shinya; Mitoma, Nobuhiko; Lin, Meng-Fang; Kizu, Takio; Tsukagoshi, Kazuhito, E-mail: GAO.Xu@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp [International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044 (Japan); Nabatame, Toshihide [MANA Foundry and MANA Advanced Device Materials Group, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044 (Japan)

    2014-07-14

    Oxide thin film transistor employing copper source/drain electrodes shows a small turn on voltage and reduced hysteresis. Cross-sectional high-resolution transmission electron microscopy image confirmed the formation of ?4?nm CuO{sub x} related interlayer. The lower bond-dissociation energy of Cu-O compared to Si-O and In-O suggests that the interlayer was formed by adsorbing oxygen molecules from surrounding environment instead of getting oxygen atoms from the semiconductor film. The formation of CuO{sub x} interlayer acting as an acceptor could suppress the carrier concentration in the transistor channel, which would be utilized to control the turn on voltage shifts in oxide thin film transistors.

  4. Diffusion in linear porous media with periodic entropy barriers: A tube formed by contacting spheres

    PubMed Central

    Vazquez, Marco-Vinicio; Berezhkovskii, Alexander M.; Dagdug, Leonardo

    2008-01-01

    The problem of transport in quasi-one-dimensional periodic structures has been studied recently by several groups [D. Reguera et al., Phys. Rev. Lett.96, 130603 (2006); P. S. Burada et al., Phys. Rev. E75, 051111 (2007); B. Q. Ai and L. G. Liu, ibid.74, 051114 (2006); B. Q. Ai et al., ibid.75, 061126 (2007); B. Q. Ai and L. G. Liu, J. Chem. Phys.126, 204706 (2007); 128, 024706 (2008); E. Yariv and K. D. Dorfman, Phys. Fluids19, 037101 (2007); N. Laachi et al., Europhys. Lett.80, 50009 (2007); A. M. Berezhkovskii et al., J. Chem. Phys.118, 7146 (2003); 119, 6991 (2003)]. Using the concept of “entropy barrier” [R. Zwanzig, J. Phys. Chem.96, 3926 (1992)] one can classify such structures based on the height of the entropy barrier. Structures with high barriers are formed by chambers, which are weakly connected with each other because they are connected by small apertures. To escape from such a chamber a diffusing particle has to climb a high entropy barrier to find an exit that takes a lot of time [I. V. Grigoriev et al., J. Chem. Phys.116, 9574 (2002)]. As a consequence, the particle intrachamber lifetime ?esc is much larger than its intrachamber equilibration time, ?rel, ?esc??rel. When the aperture is not small enough, the intrachamber escape and relaxation times are of the same order and the hierarchy fails. This is the case of low entropy barriers. Transport in this case is analyzed in the works of Schmid and co-workers, Liu and co-workers, and Dorfman and co-workers, while the work of Berezhkovskii et al. is devoted to diffusion in the case of high entropy barriers. PMID:18681682

  5. Diffusion in linear porous media with periodic entropy barriers: A tube formed by contacting spheres.

    PubMed

    Vazquez, Marco-Vinicio; Berezhkovskii, Alexander M; Dagdug, Leonardo

    2008-07-28

    The problem of transport in quasi-one-dimensional periodic structures has been studied recently by several groups [D. Reguera et al., Phys. Rev. Lett.96, 130603 (2006); P. S. Burada et al., Phys. Rev. E75, 051111 (2007); B. Q. Ai and L. G. Liu, ibid.74, 051114 (2006); B. Q. Ai et al., ibid.75, 061126 (2007); B. Q. Ai and L. G. Liu, J. Chem. Phys.126, 204706 (2007); 128, 024706 (2008); E. Yariv and K. D. Dorfman, Phys. Fluids19, 037101 (2007); N. Laachi et al., Europhys. Lett.80, 50009 (2007); A. M. Berezhkovskii et al., J. Chem. Phys.118, 7146 (2003); 119, 6991 (2003)]. Using the concept of "entropy barrier" [R. Zwanzig, J. Phys. Chem.96, 3926 (1992)] one can classify such structures based on the height of the entropy barrier. Structures with high barriers are formed by chambers, which are weakly connected with each other because they are connected by small apertures. To escape from such a chamber a diffusing particle has to climb a high entropy barrier to find an exit that takes a lot of time [I. V. Grigoriev et al., J. Chem. Phys.116, 9574 (2002)]. As a consequence, the particle intrachamber lifetime tau(esc) is much larger than its intrachamber equilibration time, tau(rel), tau(esc)>tau(rel). When the aperture is not small enough, the intrachamber escape and relaxation times are of the same order and the hierarchy fails. This is the case of low entropy barriers. Transport in this case is analyzed in the works of Schmid and co-workers, Liu and co-workers, and Dorfman and co-workers, while the work of Berezhkovskii et al. is devoted to diffusion in the case of high entropy barriers. PMID:18681682

  6. Co-Assembled Cytotoxic and Pegylated Peptide Amphiphiles Form Filamentous Nanostructures with Potent Anti-Tumor Activity in Models of Breast Cancer

    PubMed Central

    Toft, Daniel J.; Moyer, Tyson J.; Standley, Stephany M.; Ruff, Yves; Ugolkov, Andrey; Stupp, Samuel I.; Cryns, Vincent L.

    2012-01-01

    Self-assembled peptide amphiphiles (PAs) consisting of hydrophobic, hydrogen bonding, and charged hydrophilic domains form cylindrical nanofibers in physiological conditions and allow for the presentation of a high density of bioactive epitopes on the nanofiber surface. We report here on the use of PAs to form multifunctional nanostructures with tumoricidal activity. The combination of a cationic, membrane-lytic PA co-assembled with a serum-protective, pegylated PA was shown to self-assemble into nanofibers. Addition of the pegylated PA to the nanostructure substantially limited degradation of the cytolytic PA by the protease trypsin, with an eight-fold increase in the amount of intact PA observed after digestion. At the same time, addition of up to 50% pegylated PA to the nanofibers did not decrease the in vitro cytotoxicity of the cytolytic PA. Using a fluorescent tag covalently attached to PA nanofibers we were able to track the biodistribution in plasma and tissues of tumor bearing mice over time after intraperitoneal administration of the nanoscale filaments. Using an orthotopic mouse xenograft model of breast cancer, systemic administration of the cytotoxic pegylated nanostructures significantly reduced tumor cell proliferation and overall tumor growth, demonstrating the potential of multifunctional PA nanostructures as versatile cancer therapeutics. PMID:22928955

  7. Nanosulfur: A Potent Fungicide Against Food Pathogen, Aspergillus niger

    NASA Astrophysics Data System (ADS)

    Choudhury, Samrat Roy; Nair, Kishore K.; Kumar, Rajesh; Gogoi, Robin; Srivastava, Chitra; Gopal, Madhuban; Subhramanyam, B. S.; devakumar, C.; Goswami, Arunava

    2010-10-01

    Elemental sulfur (S0), man's oldest eco-friendly fungicide for curing fungal infections in plants and animals, is registered in India as a non-systemic and contact fungicide. However due to its high volume requirement, Indian agrochemical industry and farmers could not effectively use this product till date. We hypothesize that intelligent nanoscience applications might increase the visibility of nanosulfur in Indian agriculture as a potent and eco-safe fungicide. Sulfur nanoparticles (NPs) were synthesized bottom-up via a liquid synthesis method with average particle size in the range of 50-80 nm and the shapes of the NPs were spherical. A comparative study of elemental and nano-sulfur produced has been tested against facultative fungal food pathogen, Aspergillus niger. Results showed that nanosulfur is more efficacious than its elemental form.

  8. Nanosulfur: A Potent Fungicide Against Food Pathogen, Aspergillus niger

    SciTech Connect

    Choudhury, Samrat Roy; Goswami, Arunava [Agricultural and Ecological Research Unit, Biological Sciences Division, Indian Statistical Institute, 203 B. T. Road, Kolkata, West Bengal-700108 (India); Nair, Kishore K.; Kumar, Rajesh; Gopal, Madhuban; Devakumar, C. [Department of Agricultural Chemicals, Pusa Campus, New Delhi (India); Gogoi, Robin [Plant Pathology, Pusa Campus, New Delhi (India); Srivastava, Chitra; Subhramanyam, B. S. [Entomology, Indian Agricultural Research Institute, Pusa Campus, New Delhi (India)

    2010-10-04

    Elemental sulfur (S{sup 0}), man's oldest eco-friendly fungicide for curing fungal infections in plants and animals, is registered in India as a non-systemic and contact fungicide. However due to its high volume requirement, Indian agrochemical industry and farmers could not effectively use this product till date. We hypothesize that intelligent nanoscience applications might increase the visibility of nanosulfur in Indian agriculture as a potent and eco-safe fungicide. Sulfur nanoparticles (NPs) were synthesized bottom-up via a liquid synthesis method with average particle size in the range of 50-80 nm and the shapes of the NPs were spherical. A comparative study of elemental and nano-sulfur produced has been tested against facultative fungal food pathogen, Aspergillus niger. Results showed that nanosulfur is more efficacious than its elemental form.

  9. Modeling of contact theories for the manipulation of biological micro/nanoparticles in the form of circular crowned rollers based on the atomic force microscope

    SciTech Connect

    Korayem, M. H.; Khaksar, H.; Taheri, M. [Robotic Research Laboratory, Center of Excellence in Experimental Solid Mechanics and Dynamics, School of Mechanical Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)

    2013-11-14

    This article has dealt with the development and modeling of various contact theories for biological nanoparticles shaped as cylinders and circular crowned rollers for application in the manipulation of different biological micro/nanoparticles based on Atomic Force Microscope. First, the effective contact forces were simulated, and their impact on contact mechanics simulation was investigated. In the next step, the Hertz contact model was simulated and compared for gold and DNA nanoparticles with the three types of spherical, cylindrical, and circular crowned roller type contact geometries. Then by reducing the length of the cylindrical section in the circular crowned roller geometry, the geometry of the body was made to approach that of a sphere, and the results were compared for DNA nanoparticles. To anticipatory validate the developed theories, the results of the cylindrical and the circular crowned roller contacts were compared with the results of the existing spherical contact simulations. Following the development of these contact models for the manipulation of various biological micro/nanoparticles, the cylindrical and the circular crowned roller type contact theories were modeled based on the theories of Lundberg, Dowson, Nikpur, Heoprich, and Hertz for the manipulation of biological micro/nanoparticles. Then, for a more accurate validation, the results obtained from the simulations were compared with those obtained by the finite element method and with the experimental results available in previous articles. The previous research works on the simulation of nanomanipulation have mainly investigated the contact theories used in the manipulation of spherical micro/nanoparticles. However since in real biomanipulation situations, biological micro/nanoparticles of more complex shapes need to be displaced in biological environments, this article therefore has modeled and compared, for the first time, different contact theories for use in the biomanipulation of cylindrical and circular crowned roller shaped micro/nanoparticles. The results of models indicate that the contact model of Hertz achieves the largest amount of deformation for the DNA nanoparticle in cylindrical form and the contact model of Heoprich achieves the largest deformation for the circular crowned roller shaped DNA. Of course, this finding is not always true for the other nanoparticles; and considering the mechanical and environmental characteristics, different results can be obtained. Also, by comparing the deformations of different types of nanoparticles, it was determined that the platelet type nanoparticles display the highest degree of deformation in all the considered models, due to their particular mechanical characteristics.

  10. Structural and electrical characterization of silicided Ni/Au contacts formed at low temperature (<300 °C) on p-type [001] silicon

    NASA Astrophysics Data System (ADS)

    Alberti, A.; Badalà, P.; Pellegrino, G.; Santangelo, A.

    2011-12-01

    Silicided Ni/Au contacts with very low contact resistance were realized on p-type [001] silicon at low temperature by ex-situ or, alternatively, by in situ annealing processes. During the ex-situ annealing, performed at 200 °C for 10 s, a uniformly thin (14 nm) Ni2Si layer was formed having an extremely flat interface with silicon thanks to the trans-rotational structure of the silicide. During the in situ annealing, promoted by a sputter etch processing (T < 300 °C), a 44 nm-thick silicide layer was formed as a mixture of trans-rotational NiSi and epitaxial NiSi2, domains. In both cases, using a low thermal budget has guaranteed a limited consumption of silicon during the reaction process and a good adhesion with the substrate avoiding gold contaminations. As a consequence of the presence of trans-rotational domains, wherein a pseudo-epitaxial relationship between the silicide and the silicon lattices is established, an ohmic behavior was observed in a wide range of substrate doping (3.5 × 1018 ÷ 3 × 1019 B/cm3) for both annealing processes (in situ and ex-situ). On the other hand, conventional TiNiAu and CrNiAu contacts showed, in the same range of B doping concentration, a rectifying behavior with systematically higher specific contact resistance values (Rc) compared to those of the Ni silicided contacts.

  11. Campus Courtesy Card Order Form Campus Courtesy cards are available to private individuals only. BYU Departments must contact Treasury Services,

    E-print Network

    Martinez, Tony R.

    , etc. For more information on Signature Card locations, visit http@byu.edu OR print and mail to: BYU Signature Card Office 2310 WSC Provo, UT 84602 · Contact Information: Name: Phone of Cards X $0.50 + Total Amount) · Payment Options: Check Credit Card Check must be received before card

  12. Use of separate ZnTe interface layers to form ohmic contacts to p-CdTe films

    DOEpatents

    Gessert, T.A.

    1999-06-01

    A method of is disclosed improving electrical contact to a thin film of a p-type tellurium-containing II-VI semiconductor comprising: depositing a first undoped layer of ZnTe on a thin film of p-type tellurium containing II-VI semiconductor with material properties selected to limit the formation of potential barriers at the interface between the p-CdTe and the undoped layer, to a thickness sufficient to control diffusion of the metallic-doped ZnTe into the p-type tellurium-containing II-VI semiconductor, but thin enough to minimize affects of series resistance; depositing a second heavy doped p-type ZnTe layer to the first layer using an appropriate dopant; and depositing an appropriate metal onto the outer-most surface of the doped ZnTe layer for connecting an external electrical conductor to an ohmic contact. 11 figs.

  13. Use of separate ZnTe interface layers to form OHMIC contacts to p-CdTe films

    DOEpatents

    Gessert, Timothy A. (Conifer, CO)

    1999-01-01

    A method of improving electrical contact to a thin film of a p-type tellurium-containing II-VI semiconductor comprising: depositing a first undoped layer of ZnTe on a thin film of p-type tellurium containing II-VI semiconductor with material properties selected to limit the formation of potential barriers at the interface between the p-CdTe and the undoped layer, to a thickness sufficient to control diffusion of the metallic-doped ZnTe into the p-type tellurim-containing II-VI semiconductor, but thin enough to minimize affects of series resistance; depositing a second heavy doped p-type ZnTe layer to the first layer using an appropriate dopant; and depositing an appropriate metal onto the outer-most surface of the doped ZnTe layer for connecting an external electrical conductor to an ohmic contact.

  14. Bestllningsblankett/order form till LiU-Tryck -IDA -Avhandling Kontaktperson LiU-Tryck/Contact printing office

    E-print Network

    Zhao, Yuxiao

    lämnas till lab-administratören samt Anne Moe för kännedom. �nskas fler kopior eller färgtryck / Extra copies or colour print? E-post/E-mail address: E-post/E-mail address: If NOT published in Electronic Press - Contact Anne for number of copies! Lab-administratör namn /Lab secretary's name: COPIES

  15. Activation of non-sensitizing or low-sensitizing fragrance substances into potent sensitizers - prehaptens and prohaptens.

    PubMed

    Karlberg, Ann-Therese; Börje, Anna; Duus Johansen, Jeanne; Lidén, Carola; Rastogi, Suresh; Roberts, David; Uter, Wolfgang; White, Ian R

    2013-12-01

    Experimental and clinical studies have shown that fragrance substances can act as prehaptens or prohaptens. They form allergens that are more potent than the parent substance by activation outside or in the skin via abiotic (chemical and physical factors) and/or biotic activation, thus, increasing the risk of sensitization. In the present review a series of fragrance substances with well documented abiotic and/or biotic activation are given as indicative and illustrative examples of the general problem. Commonly used fragrance substances, also found in essential oils, autoxidize on contact with air, forming potent sensitizers that can be an important source for contact allergy to fragrances and fragranced products. Some of them can act as prohaptens and be activated in the skin as well. The experimental findings are confirmed in large clinical studies. When substances with structural alerts for acting as prohaptens and/or prehaptens are identified, the possibility of generating new potent allergens should be considered. Predictive testing should include activation steps. Further experimental and clinical research regarding activation of fragrance substances is needed to increase consumer safety. PMID:24107147

  16. ATBC Study - Contact Us

    Cancer.gov

    Skip to Main Content Home Contact Us Links Study Details Questionnaires & Forms Current Projects ATBC Study Bibliography Study Investigators & Collaborators Proposal Review & Collaboration Research Consortium Projects Contact Us If you are seeking general

  17. NCI-Frederick PHL - Contact

    Cancer.gov

    Services Price List Courier Services & Shipment Procedures Scheduling Contact Information Related Links Establishing an Account PHL Forms PHL Portal Contact Information Manager: Larry Sternberg, Ph.D., Department Contact Phone Number E-mail Address

  18. Contact-based sequence alignment

    Microsoft Academic Search

    Jens Kleinjung; John Romein; Kuang Lin; Jaap Heringa

    2004-01-01

    This paper introduces the novel method of contact- based protein sequence alignment, where structural information in the form of contact mutation prob- abilities is incorporated into an alignment routine using contact-mutation matrices (CAO: Contact Accepted mutatiOn). The contact-based alignment routine optimizes the score of matched contacts, which involves four (two per contact) instead of two residues per match in pairwise

  19. Structural and transport properties in alloyed Ti/Al Ohmic contacts formed on p-type Al-implanted 4H-SiC annealed at high temperature

    NASA Astrophysics Data System (ADS)

    Frazzetto, A.; Giannazzo, F.; Lo Nigro, R.; Raineri, V.; Roccaforte, F.

    2011-06-01

    In this paper, the transport properties of alloyed Ti/Al Ohmic contacts formed on p-type Al-implanted silicon carbide (4H-SiC) were studied. The morphology of p-type implanted 4H-SiC was controlled using a capping layer during post-implantation activation annealing at 1700 °C. The different morphological conditions do not affect the macroscopic electrical properties of the implanted SiC (such as the sheet resistance or the mobility). On the other hand, the improved morphology of implanted SiC allows us to achieve a flatter Ti/Al surface and a lower specific contact resistance. The temperature dependence of the specific resistance of the contacts was studied to obtain physical insights into the carrier transport mechanism at the metal/SiC interface. The fit comparing several models shows that thermionic field emission is the dominant transport mechanism through the metal/SiC interface, and that a reduction in the barrier height from 0.51 to 0.46 eV is associated with the improvement of the Ohmic properties. Transmission electron microscopy analysis showed the presence of a laterally inhomogeneous microstructure of the metal/SiC interface. The reduction in the barrier height could be correlated with the different microstructures of the interfacial region.

  20. Staphylococcal alpha -toxin: Oligomerization of Hydrophilic Monomers to Form Amphiphilic Hexamers Induced through Contact with Deoxycholate Detergent Micelles

    Microsoft Academic Search

    Sucharit Bhakdi; Roswitha Fussle; Jorgen Tranum-Jensen

    1981-01-01

    Native staphylococcus aureus alpha -toxin is secreted as a hydrophilic polypeptide chain of Mr 34,000. The presence of deoxycholate above the critical micellar concentration induced the toxin monomers to self-associate, forming ring or cylindrical oligomers. The oligomers were amphiphilic and bound detergent. In deoxycholate solution, the protein-detergent complexes exhibited a sedimentation coefficient of 10.4 S. A Mr of 238,700 was

  1. Contact Dermatitis

    MedlinePLUS

    ... Z Diseases and treatments A - D Contact dermatitis Contact dermatitis Contact dermatitis : Many health care workers develop ... happen immediately. Most take time to appear. Allergic contact dermatitis Some people have an allergic skin reaction. ...

  2. The relative noise levels of parallel axis gear sets with various contact ratios and gear tooth forms

    NASA Technical Reports Server (NTRS)

    Drago, Raymond J.; Lenski, Joseph W., Jr.; Spencer, Robert H.; Valco, Mark; Oswald, Fred B.

    1993-01-01

    The real noise reduction benefits which may be obtained through the use of one gear tooth form as compared to another is an important design parameter for any geared system, especially for helicopters in which both weight and reliability are very important factors. This paper describes the design and testing of nine sets of gears which are as identical as possible except for their basic tooth geometry. Noise measurements were made at various combinations of load and speed for each gear set so that direct comparisons could be made. The resultant data was analyzed so that valid conclusions could be drawn and interpreted for design use.

  3. Texas A&M Identity Services One Time Data Request For help with completing this form, contact IT Infrastructure & Operations at idm-support@tamu.edu or the Identity Management Office at

    E-print Network

    Texas A&M Identity Services One Time Data Request For help with completing this form, contact IT Infrastructure & Operations at idm-support@tamu.edu or the Identity Management Office at 979.845.4300. Email the completed form to idm-support@tamu.edu, fax to 979.845.6090, or mail to Identity Management Office, MS 3374

  4. Contact dermatitis

    MedlinePLUS

    Dermatitis - contact; Allergic dermatitis; Dermatitis - allergic ... There are two types of contact dermatitis. Irritant dermatitis: This is the most common type. It can be by contact with acids, alkaline materials such as soaps ...

  5. Highly potent silver-organoalkoxysilane antimicrobial porous nanomembrane

    PubMed Central

    2013-01-01

    We used a simple electrospinning technique to fabricate a highly potent silver-organoalkoxysilane antimicrobial composite from AgNO3-polyvinylpyrrolidone (PVP)/3-aminopropyltrimethoxysilane (APTMS)/tetraethoxysilane (TEOS) solution. Spectroscopic and microscopic analyses of the composite showed that the fibers contain an organoalkoxysilane ‘skeleton,’ 0.18 molecules/nm2 surface amino groups, and highly dispersed and uniformly distributed silver nanoparticles (5 nm in size). Incorporation of organoalkoxysilanes is highly beneficial to the antimicrobial mat as (1) amino groups of APTMS are adhesive and biocidal to microorganisms, (2) polycondensation of APTMS and TEOS increases the membrane’s surface area by forming silicon bonds that stabilize fibers and form a composite mat with membranous structure and high porosity, and (3) the organoalkoxysilanes are also instrumental to the synthesis of the very small-sized and highly dispersed silver metal particles in the fiber mat. Antimicrobial property of the composite was evaluated by disk diffusion, minimum inhibition concentration (MIC), kinetic, and extended use assays on bacteria (Escherichia coli, Bacillus anthracis, Staphylococcus aureus, and Brucella suis), a fungus (Aspergillus niger), and the Newcastle disease virus. The membrane shows quick and sustained broad-spectrum antimicrobial activity. Only 0.3 mg of fibers is required to achieve MIC against all the test organisms. Bacteria are inhibited within 30 min of contact, and the fibers can be used repeatedly. The composite is silver efficient and environment friendly, and its membranous structure is suitable for many practical applications as in air filters, antimicrobial linen, coatings, bioadhesives, and biofilms. PMID:23574791

  6. MEMBERSHIP INTEREST FORM Contact Information

    E-print Network

    of over 100 men and women who are dedicated to enhancing cooperation and understanding between sciences, while preparing them for roles as future agricultural leaders. INTERACTION THROUGH ORGANIZATION

  7. NCI-Frederick FACILITY - Contact

    Cancer.gov

      FACILITY Data Management Home System Overview How to Get Started Training User Information Forms Contact Information LASP Online Access System Administration Contact Information If you have questions, concerns, or suggestions regarding your use of

  8. TCGA Contacts

    Cancer.gov

    Home About TCGA People and Contacts TCGA Contacts TCGA Contacts For more information about The Cancer Genome Atlas Program, please contact: The Cancer Genome Atlas Program OfficeNational Cancer Institute at NIH31 Center DriveBldg. 31, Suite 3A20Bethesda,

  9. Hierarchical multicolor nano-pixel matrices formed by coordinating luminescent metal ions to a conjugated poly(4?-octyl-2?,6?-bispyrazoyl pyridine) film via contact printing

    PubMed Central

    Basak, Supratim; Mohiddon, Md Ahamad; Baumgarten, Martin; Müllen, Klaus; Chandrasekar, Rajadurai

    2015-01-01

    We introduce a cost-effective, yet feasible reactive printing approach namely, “coordination chemistry at the conjugated ligand polymer surface”. By using a contact printing technique we selectively fabricated high resolution nano-pixel configurations consisting of red, blue and green (R,G,B) colors arranged in a hierarchical three-dimensional fashion. For this, we have synthesized a novel blue emitting conjugated ligand polymer, [poly(4?-octyl-2?,6?-bispyrazoyl pyridine)] ( ~ 7–8?KDa) having a tridentate ligand in its repeating unit which forms a thin film prone of binding metal ions. On top of this ligand polymer film, a layer of high-resolution cross-stripes (width ca. 800?nm) was printed comprised of Eu and Tb ions over a large area ~ 100 × 100??m2. The final woodpile-like assembly produced a new pixel group consisting of B; BG; BR; and BGR (White) colors. The area of the white emitting square is ca. 0.64??m2. The patterned layers that make up the pixels are very thin and thus this new technique might find applications in flexible light emitting devices. PMID:25673007

  10. Hierarchical multicolor nano-pixel matrices formed by coordinating luminescent metal ions to a conjugated poly(4?-octyl-2?,6?-bispyrazoyl pyridine) film via contact printing

    NASA Astrophysics Data System (ADS)

    Basak, Supratim; Mohiddon, Md Ahamad; Baumgarten, Martin; Müllen, Klaus; Chandrasekar, Rajadurai

    2015-02-01

    We introduce a cost-effective, yet feasible reactive printing approach namely, ``coordination chemistry at the conjugated ligand polymer surface''. By using a contact printing technique we selectively fabricated high resolution nano-pixel configurations consisting of red, blue and green (R,G,B) colors arranged in a hierarchical three-dimensional fashion. For this, we have synthesized a novel blue emitting conjugated ligand polymer, [poly(4'-octyl-2',6'-bispyrazoyl pyridine)] ( ~ 7-8 KDa) having a tridentate ligand in its repeating unit which forms a thin film prone of binding metal ions. On top of this ligand polymer film, a layer of high-resolution cross-stripes (width ca. 800 nm) was printed comprised of Eu and Tb ions over a large area ~ 100 × 100 ?m2. The final woodpile-like assembly produced a new pixel group consisting of B; BG; BR; and BGR (White) colors. The area of the white emitting square is ca. 0.64 ?m2. The patterned layers that make up the pixels are very thin and thus this new technique might find applications in flexible light emitting devices.

  11. Muon radiography and deformation analysis of the lava dome formed by the 1944 eruption of Usu, Hokkaido —Contact between high-energy physics and volcano physics—

    PubMed Central

    TANAKA, Hiroyuki K. M.; YOKOYAMA, Izumi

    2008-01-01

    Lava domes are one of the conspicuous topographic features on volcanoes. The subsurface structure of the lava dome is important to discuss its formation mechanism. In the 1944 eruption of Volcano Usu, Hokkaido, a new lava dome was formed at its eastern foot. After the completion of the lava dome, various geophysical methods were applied to the dome to study its subsurface structure, but resulted in a rather ambiguous conclusion. Recently, from the results of the levelings, which were repeated during the eruption, “pseudo growth curves” of the lava dome were obtained. The curves suggest that the lava dome has a bulbous shape. In the present work, muon radiography, which previously proved effective in imaging the internal structure of Volcano Asama, has been applied to the Usu lava dome. The muon radiography measures the distribution of the “density length” of volcanic bodies when detectors are arranged properly. The result obtained is consistent with the model deduced from the pseudo growth curves. The measurement appears to afford useful method to clarify the subsurface structure of volcanoes and its temporal changes, and in its turn to discuss volcanic processes. This is a point of contact between high-energy physics and volcano physics. PMID:18941290

  12. Semiconductor ohmic contact

    NASA Technical Reports Server (NTRS)

    Hawrylo, F. Z.; Kressel, H.

    1977-01-01

    Contact formed on p-type surface of semiconductor laser has several advantages: highly conductive degenerate region and narrow band gap provides surface for good metal-to-semiconductor contact; lattice parameter of GaAs is 5.6533 A; improved lattice match eases interface strain which reduces interface cracking of semiconductor material.

  13. Making Contact. Generating Interethnic Contact for Multicultural Integration and Tolerance in Amsterdam

    ERIC Educational Resources Information Center

    Muller, Floris

    2012-01-01

    Interethnic contact is considered a potent tool for the generation of interethnic understanding and tolerance. This faith has engendered countless social projects that seek to stimulate contact between members of different ethnic groups under "optimal conditions". However, the academic literature does not stipulate how, if at all, these optimal…

  14. This form is for additions or changes to existing web sites/pages in the college. For specific functionality or to create a new web site, please contact the web development team directly at websupport@cvm.tamu.edu

    E-print Network

    functionality or to create a new web site, please contact the web development team directly at websupportThis form is for additions or changes to existing web sites/pages in the college. For specific (including links, references to pictures, and paragraphs) should be placed in this section.] Web Change

  15. Celebrity Patients, VIPs, and Potentates

    PubMed Central

    Groves, James E.; Dunderdale, Barbara A.; Stern, Theodore A.

    2002-01-01

    Background: During the second half of the 20th century, the literature on the doctor-patient relationship mainly dealt with the management of “difficult” (personality-disordered) patients. Similar problems, however, surround other types of “special” patients. Method: An overview and analysis of the literature were conducted. As a result, such patients can be subcategorized by their main presentations; each requires a specific management strategy. Results: Three types of “special” patients stir up irrational feelings in their caregivers. Sick celebrities threaten to focus public scrutiny on the private world of medical caregivers. VIPs generate awe in caregivers, with loss of the objectivity essential to the practice of scientific medicine. Potentates unearth narcissism in the caregiver-patient relationship, which triggers a struggle between power and shame. Pride, privacy, and the staff's need to be in control are all threatened by introduction of the special patient into medicine's closed culture. Conclusion: The privacy that is owed to sick celebrities should be extended to protect overexposed staff. The awe and loss of medical objectivity that VIPs generate are counteracted by team leadership dedicated to avoiding any deviation from standard clinical procedure. Moreover, the collective ill will surrounding potentates can be neutralized by reassuring them that they are “special”—and by caregivers mending their own vulnerable self-esteem. PMID:15014712

  16. Investigation of montmorillonite alteration and form of iron corrosion products in compacted bentonite in contact with carbon steel for ten years

    NASA Astrophysics Data System (ADS)

    Ishidera, Takamitsu; Ueno, Kenichi; Kurosawa, Seiichi; Suyama, Tadahiro

    In high-level radioactive waste disposal, the alteration of montmorillonite due to the corrosion of carbon steel possibly affects the swelling and self-healing capacity of compacted bentonite used as a buffer material. The nature of the corrosion products in compacted bentonite is also important to evaluate not only the diffusion and sorption behavior of radionuclides but also the chemical composition and redox potential of pore water. In this study, the alteration of montmorillonite in compacted bentonite due to the interaction with carbon steel was analyzed by X-ray diffraction (XRD). The possibility of montmorillonite alteration was also investigated from the cation exchange capacity (CEC) of compacted bentonite and scanning electron microscopy (SEM) observation. The corrosion products distributed in the compacted bentonite were investigated by selective dissolution analysis, which can estimate the crystallinity of Fe-bearing compounds. The valence of Fe in the corrosion products was spectrophotometrically determined. From the XRD analysis, newly formed phyllosilicates resulting from the alteration of montmorillonite could not be identified in compacted bentonite. CEC of compacted bentonite adjacent to the carbon steel, in which high concentration of Fe was extracted, was hardly decreased. No significant differences of clay particles were observed with SEM. Thus, the alteration of montmorillonite was scarcely detected in compacted bentonite in contact with carbon steel for ten years. The selective dissolution and valence analyses suggest that most of the corrosion products of carbon steel existed in Kunipia F, which consists of over 95 wt% montmorillonite, was amorphous, non-crystalline or poorly ordered Fe(OH) 2. This means that Fe(OH) 2 distributed into compacted bentonite was scarcely crystallized within ten years at 80 oC. From the XRD analysis, small amount of green rust one containing Cl - at the interlayers (GR1(Cl -)) and lepidocrocite were also identified in Kunipia F. Therefore, under this experimental condition, Fe(OH) 2 formed in Kunipia F due to the corrosion of carbon steel was oxidized to GR1(Cl -) as intermediates, and then GR1(Cl -) was possibly oxidized to lepidocrocite. On the other hand, GR1(Cl -) was hardly detected in Kunigel V1, which contains 46-49 wt% montmorillonite, from the XRD analysis.

  17. Contact Information

    Cancer.gov

    Contact Information For information regarding the agenda or meeting content, please contact: Beverly Meadows, PhD, RN, OCN Division of Cancer Prevention National Cancer Institute National Institutes of Health 6130 Executive Boulevard Bethesda, MD 20852 Phone:

  18. Contact Information

    Cancer.gov

    Contact Information For workshop logistical information, please contact: Fofie Witter Senior Conference Manager Cabezon Group, Inc., Suite 100 11821 Parklawn Drive Rockville, MD 20852 Phone: (301) 468-6087 or (240) 786-9130, ext. 32 Fax: (301)

  19. Contact Us

    Cancer.gov

    If you have any questions or need more information on federal legislation and congressional activity affecting cancer research, please contact us!  Be sure to include your e-mail address and office telephone number. Contact information National Cancer

  20. Contact Information

    Cancer.gov

    Meetings & Events Cancer Prevention and Control Investigators Meeting Tuesday, March 20, 2012 Contact Information For workshop logistical information, please contact: Fofie Witter Senior Conference Manager Cabezon Group, Inc. Suite 100 11821 Parklawn

  1. RAPID Contacts

    Cancer.gov

    Rapid Access to Preventive Intervention Development (RAPID) Program Contacts Program Contact RAPID ProgramAttn: Izet M. Kapetanovic, PhD, Program Director Chemopreventive Agent Development Research Group Division of Cancer Prevention, NCI Executive Plaza

  2. Controlling interface oxygen for forming Ag ohmic contact to semi-polar (1 1 -2 2) plane p-type GaN

    NASA Astrophysics Data System (ADS)

    Park, Jae-Seong; Han, Jaecheon; Seong, Tae-Yeon

    2014-11-01

    Low-resistance Ag ohmic contacts to semi-polar (1 1 -2 2) p-GaN were developed by controlling interfacial oxide using a Zn layer. The 300 °C-annealed Zn/Ag samples showed ohmic behavior with a contact resistivity of 6.0 × 10-4 ? cm2 better than that of Ag-only contacts (1.0 × 10-3 ? cm2). The X-ray photoemission spectroscopy (XPS) results showed that annealing caused the indiffusion of oxygen at the contact/GaN interface, resulting in the formation of different types of interfacial oxides, viz. Ga-oxide and Ga-doped ZnO. Based on the XPS and electrical results, the possible mechanisms underlying the improved electrical properties of the Zn/Ag samples are discussed.

  3. Design and Synthesis of Potent, Selective Inhibitors of Matriptase

    PubMed Central

    2012-01-01

    Matriptase is a member of the type II transmembrane serine protease family. Several studies have reported deregulated matriptase expression in several types of epithelial cancers, suggesting that matriptase constitutes a potential target for cancer therapy. We report herein a new series of slow, tight-binding inhibitors of matriptase, which mimic the P1–P4 substrate recognition sequence of the enzyme. Preliminary structure–activity relationships indicate that this benzothiazole-containing RQAR-peptidomimetic is a very potent inhibitor and possesses a good selectivity for matriptase versus other serine proteases. A molecular model was generated to elucidate the key contacts between inhibitor 1 and matriptase. PMID:24900505

  4. Noneczematous Contact Dermatitis

    PubMed Central

    Foti, Caterina; Vestita, Michelangelo; Angelini, Gianni

    2013-01-01

    Irritant or allergic contact dermatitis usually presents as an eczematous process, clinically characterized by erythematoedematovesicous lesions with intense itching in the acute phase. Such manifestations become erythematous-scaly as the condition progresses to the subacute phase and papular-hyperkeratotic in the chronic phase. Not infrequently, however, contact dermatitis presents with noneczematous features. The reasons underlying this clinical polymorphism lie in the different noxae and contact modalities, as well as in the individual susceptibility and the various targeted cutaneous structures. The most represented forms of non-eczematous contact dermatitis include the erythema multiforme-like, the purpuric, the lichenoid, and the pigmented kinds. These clinical entities must obviously be discerned from the corresponding “pure” dermatitis, which are not associated with contact with exogenous agents. PMID:24109520

  5. Activated human platelets induce factor XIIa-mediated contact activation.

    PubMed

    Bäck, Jennie; Sanchez, Javier; Elgue, Graciela; Ekdahl, Kristina Nilsson; Nilsson, Bo

    2010-01-01

    Earlier studies have shown that isolated platelets in buffer systems can promote activation of FXII or amplify contact activation, in the presence of a negatively charge substance or material. Still proof is lacking that FXII is activated by platelets in a more physiological environment. In this study we investigate if activated platelets can induce FXII-mediated contact activation and whether this activation affects clot formation in human blood. Human platelets were activated with a thrombin receptor-activating peptide, SFLLRN-amide, in platelet-rich plasma or in whole blood. FXIIa and FXIa in complex with preferentially antithrombin (AT) and to some extent C1-inhibitor (C1INH) were generated in response to TRAP stimulation. This contact activation was independent of surface-mediated contact activation, tissue factor pathway or thrombin. In clotting whole blood FXIIa-AT and FXIa-AT complexes were specifically formed, demonstrating that AT is a potent inhibitor of FXIIa and FXIa generated by platelet activation. Contact activation proteins were analyzed by flow cytometry and FXII, FXI, high-molecular weight kininogen, and prekallikrein were detected on activated platelets. Using chromogenic assays, enzymatic activity of platelet-associated FXIIa, FXIa, and kallikrein were demonstrated. Inhibition of FXIIa in non-anticoagulated blood also prolonged the clotting time. We conclude that platelet activation triggers FXII-mediated contact activation on the surface and in the vicinity of activated platelets. This leads specifically to generation of FXIIa-AT and FXIa-AT complexes, and contributes to clot formation. Activated platelets may thereby constitute an intravascular locus for contact activation, which may explain the recently reported importance of FXII in thrombus formation. PMID:19878657

  6. Electrical, chemical, and structural characterization of the interface formed between nickel/gold and palladium/gold ohmic contacts and cleaned p-type gallium nitride (0001) surfaces

    NASA Astrophysics Data System (ADS)

    Hartlieb, Philip John

    2002-09-01

    Characterization of pre-treated, Mg-doped, p-type GaN(0001) surfaces and Ni/Au and Pd/Au contact structures sequentially deposited on these surfaces has been conducted using X-ray and ultra-violet photoelectron spectroscopies, low energy electron diffraction, atomic force microscopy, scanning electron microscopy, X-ray diffraction, and current-voltage measurements. The effects or several in-situ cleaning techniques, including vacuum annealing, high-temperature nitrogen plasma pre-treatment, and ammonia-based chemical vapor cleaning, on the chemical and electronic properties of the GaN surface have also been assessed. The last technique was the most effective. Stoichiometric surfaces without detectable carbon and an 87% reduction in the surface oxygen to 2 +/- 1 at% were achieved. The band bending and electron affinity at the cleaned surface were within the ranges of 0.7--1.5eV and 2.5--3.2eV, respectively. Ni/Au contact structures deposited on both vacuum annealed and chemical vapor cleaned p-type GaN surfaces and Pd/Au contacts deposited on a chemical vapor cleaned surface were significantly less rectifying than identical contact structures deposited on conventional HCl treated surfaces, as evidenced by larger currents at equivalent voltages in the former two structures. The room temperature specific contact resistivity of these contacts deposited on vacuum annealed surfaces increased from 0.14 +/- 0.04 O•cm 2 to 0.30 +/- 0.04 O•cm2 following annealing at 140°C--150°C for 40 +/- 2min. Identical contact structures on chemical vapor cleaned surfaces performed consistently with no degradation following operation within the same ranges of temperature and time. The formation of Au:Ga (90:10) and Au:Ni (90:10) solid solutions was indicated by the results of X-ray diffraction (o-2theta) studies for Ni/Au contacts on HCl-treated surfaces following a 450°C anneal. Similar studies showed no evidence of interfacial reactions between similarly annealed contacts and chemical vapor cleaned GaN surfaces. Pd/Au contact structures on chemical vapor cleaned surfaces demonstrated excellent high-temperature microstructural stability as evidenced by the absence of significant change in the surface roughness, which was measured to be 6.9 +/- 0.4 nm after successive annealing through 700°C. Identical contact structures on HCl-treated surfaces exhibited poor high temperature microstructural stability, as indicated by a significant increase in the surface roughness to 11.8 +/- 0.5 nm and 80.2 +/- 0.5 nm following successive anneals at 600 and 700°C, respectively.

  7. Abstract--At elevated temperatures Si reacts with SiO2 to form a volatile SiO. This process affects edges of contact windows in

    E-print Network

    Technische Universiteit Delft

    are affected. Depending on the pre-baking temperature, an undercut cavity at the edges of contact windows may of the temperature was kept constant at 10 °C/s, while the ramp-down rate was determined by the cooling speed temperatures silicon dioxide decomposes and desorbs, and evidence that the reaction 2Si + SiO 2SiO (1

  8. Micro fluid contact printing of sol–gel-derived in-situ formed catalysts for the structured growth of carbon nanotubes

    Microsoft Academic Search

    Bernd Dittert; Iris Bergmair; Roland Haubner; Rainer Schöftner

    2010-01-01

    We present a novel method for the structured growth of carbon nanotubes using micrometer scaled dots of iron doped alumina and titania as catalyst system. To obtain the dots, sol–gel derived inks are deposited on quartz glass surfaces via a novel micro fluid contact printing (µFCP) method basing on inorganic inks and an Ormocer® hard stamp, and consolidated by a

  9. A Potent Peptidomimetic Inhibitor of Botulinum Neurotoxin Serotype a Has a Very Different Conformation Than SNAP-25 Substrate

    SciTech Connect

    Zuniga, J.E.; Schmidt, J.J.; Fenn, T.; Burnett, J.C.; Arac, D.; Gussio, R.; Stafford, R.G.; Badie, S.S.; Bavari, S.; Brunger, A.T.

    2009-05-28

    Botulinum neurotoxin serotype A is the most lethal of all known toxins. Here, we report the crystal structure, along with SAR data, of the zinc metalloprotease domain of BoNT/A bound to a potent peptidomimetic inhibitor (Ki = 41 nM) that resembles the local sequence of the SNAP-25 substrate. Surprisingly, the inhibitor adopts a helical conformation around the cleavage site, in contrast to the extended conformation of the native substrate. The backbone of the inhibitor's P1 residue displaces the putative catalytic water molecule and concomitantly interacts with the 'proton shuttle' E224. This mechanism of inhibition is aided by residue contacts in the conserved S1' pocket of the substrate binding cleft, and the induction of new hydrophobic pockets, which are not present in the apo form, especially for the P2' residue of the inhibitor. Our inhibitor is specific for BoNT/A as it does not inhibit other BoNT serotypes or thermolysin.

  10. Contact-based sequence alignment.

    PubMed

    Kleinjung, Jens; Romein, John; Lin, Kuang; Heringa, Jaap

    2004-01-01

    This paper introduces the novel method of contact-based protein sequence alignment, where structural information in the form of contact mutation probabilities is incorporated into an alignment routine using contact-mutation matrices (CAO: Contact Accepted mutatiOn). The contact-based alignment routine optimizes the score of matched contacts, which involves four (two per contact) instead of two residues per match in pairwise alignments. The first contact refers to a real side-chain contact in a template sequence with known structure, and the second contact is the equivalent putative contact of a homologous query sequence with unknown structure. An algorithm has been devised to perform a pairwise sequence alignment based on contact information. The contact scores were combined with PAM-type (Point Accepted Mutation) substitution scores after parameterization of gap penalties and score weights by means of a genetic algorithm. We show that owing to the structural information contained in the CAO matrices, significantly improved alignments of distantly related sequences can be obtained. This has allowed us to annotate eight putative Drosophila IGF sequences. Contact-based sequence alignment should therefore prove useful in comparative modelling and fold recognition. PMID:15121903

  11. Solar cell contact formation using laser ablation

    DOEpatents

    Harley, Gabriel; Smith, David D.; Cousins, Peter John

    2014-07-22

    The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline materiat layer; and forming conductive contacts in the plurality of contact holes.

  12. Solar cell contact formation using laser ablation

    DOEpatents

    Harley, Gabriel; Smith, David; Cousins, Peter

    2012-12-04

    The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline material layer; and forming conductive contacts in the plurality of contact holes.

  13. Contact Mechanics

    Microsoft Academic Search

    K. L. Johnson

    1987-01-01

    This book describes the stresses and deformations of solid bodies in contact with each other, along curved surfaces that touch initially at a point of contact or along a line. Examples are a railroad track and the wheels running on it, or a pair of meshed gear teeth. The book commences with the development of the theory since the problem

  14. Contact electrification

    Microsoft Academic Search

    J. Lowell; A. C. Rose-Innes

    1980-01-01

    If two materials are brought into contact and then separated they are found to be charged; this is the phenomenon of `contact electrification'. The subject falls naturally into three divisions---electrification of metals by metals; of insulators by metals; and of insulators by insulators. The first of these is well understood; charge transfer between metals is such as to bring the

  15. Contact Information

    Cancer.gov

    Contact Information For logistical information, please contact: Fofie Witter Senior Conference Manager Cabezon Group, Inc. 11821 Parklawn Drive Suite 100 Rockville, MD 20852 Phone: (301) 468-6087 or (240) 786-9130, ext. 32 Fax: (301) 770-1726 E-mail:

  16. Contact Information

    Cancer.gov

    Contact Information For Logistical Information, please contact: Fofie Witter Conference Manager Cabezon Group, Inc. 11821 Parklawn Drive Suite 100 Rockville, MD 20852 Phone: (301) 468-6008, ext. 503 or (240) 786-9130, ext. 32 Fax: (301) 468-0338 Email:

  17. Contact Information

    Cancer.gov

    Contact Information For logistical information, please contact: Fofie Witter Senior Conference Manager Cabezon Group, Inc. Suite 100 11821 Parklawn Drive Rockville, MD 20852 Phone: (301) 468-6087 or 240-786-9130, ext. 32 Fax: (301) 770-1726 E-mail:

  18. Contact Information

    Cancer.gov

    Contact Information For logistical information, please contact Fofie Witter Senior Conference Manager Capital Consulting Corporation Suite 100 11821 Parklawn Drive Rockville, MD 20852 Phone: (301) 468-6087 or (240) 786-9130, ext. 32 Fax: (301) 770-1726 E-mail:

  19. Cross-contact chain

    NASA Technical Reports Server (NTRS)

    Lieneweg, Udo (Inventor)

    1988-01-01

    A system is provided for use with wafers that include multiple integrated circuits that include two conductive layers in contact at multiple interfaces. Contact chains are formed beside the integrated circuits, each contact chain formed of the same two layers as the circuits, in the form of conductive segments alternating between the upper and lower layers and with the ends of the segments connected in series through interfaces. A current source passes a current through the series-connected segments, by way of a pair of current tabs connected to opposite ends of the series of segments. While the current flows, voltage measurements are taken between each of a plurality of pairs of voltage tabs, the two tabs of each pair connected to opposite ends of an interface that lies along the series-connected segments. A plot of interface conductances on a normal probability chart, enables prediction of the yield of good integrated circuits from the wafer.

  20. Cross-contact chain

    NASA Technical Reports Server (NTRS)

    Lieneweg, U. (inventor)

    1986-01-01

    A system is provided for use with wafers that include multiple integrated circuits that include two conductive layers in contact at multiple interfaces. Contact chains are formed beside the integrated circuits, each contact chain formed of the same two layers as the circuits, in the form of conductive segments alternating between the upper and lower layers and with the ends of the segments connected in series through interfaces. A current source passes a current through the series-connected segments, by way of a pair of current tabs connected to opposite ends of the series of segments. While the current flows, voltage measurements are taken between each of a plurality of pairs of voltage tabs, the two tabs of each pair connected to opposite ends of an interface that lies along the series-connected segments. A plot of interface conductances on normal probability chart enables prediction of the yield of good integrated circuits from the wafer.

  1. 3415 FR.01 International Information Form (IIF) & Substitute IRS Form W-8 BEN 10/27/2009 Questions? Contact University Tax Office (203) 432-5597 or daysi.cardona@yale.edu Page 1 of 3

    E-print Network

    or green card inside your passport), copy of U.S. visa stamp, ID page from passport and form I-20, form DS: ______________________________ Country Issuing Passport: _______________________________ Passport

  2. Potent Anti-Cancer Toxin

    Cancer.gov

    SKIP ALL NAVIGATION SKIP TO SUB MENU Search Site Standard Forms & Agreements Co-Development & Resources Careers & Training Intellectual Property & Inventions About TTC Overview Biomarkers Available Opportunities Resources Get Connected with TTC Complete

  3. Contact LSS

    Cancer.gov

    Key Programs Lung Screening Feasibility Study (LSS) Contact Information Dorothy Sullivan, Assistant Project Officer Director of Communications and Public Affairs for the PLCO Early Detection Research Group Phone: (301) 496-7459 ds255j@nih.gov

  4. Contact Information

    Cancer.gov

    Contact Information Capital Consulting Corporation is providing logistical support for this meeting. If you have questions or need assistance, please call Jennifer Adona at (301) 468-6073, or e-mail her at jenniferk@capconcorp.com.

  5. Types of Contact Lenses

    MedlinePLUS

    ... Consumer Devices Consumer Products Contact Lenses Types of Contact Lenses There are two general categories of contact ... Orthokeratology (Ortho-K) Decorative (Plano) Contact Lenses Soft Contact Lenses Soft contact lenses are made of soft, ...

  6. Determining the mechanism of membrane permeabilizing peptides: Identification of potent, equilibrium pore-formers

    PubMed Central

    Krauson, Aram J.; He, Jing

    2012-01-01

    To enable selection and characterization of highly potent pore-forming peptides, we developed a set of novel assays to probe 1) the potency of peptide pores at very low peptide concentration; 2) the presence or absence of pores in membranes after equilibration; 3) the interbilayer exchangeability of pore-forming peptides; and 4) the degree to which pore-forming peptides disrupt the bilayer organization at equilibrium. Here, we use these assays to characterize, in parallel, six membrane-permeabilizing peptides belonging to multiple classes. We tested the antimicrobial peptides LL37 and dermaseptin S1, the well-known natural lytic peptides melittin and alamethicin, and the very potent lentivirus lytic peptides LLP1 and LLP2 from the cytoplasmic domain of HIV GP41. The assays verified that that the antimicrobial peptides are not potent pore formers, and form only transient permeabilization pathways in bilayers which are not detectable at equilibrium. The other peptides are far more potent and form pores that are still detectable in vesicles after many hours. Among the peptides studies, alamethicin is unique in that it is very potent, readily exchanges between vesicles and disturbs the local bilayer structure even at very low concentration. The equally potent LLP peptides do not exchange readily and do not perturb the bilayer at equilibrium. Comparison of these classes of pore forming peptides in parallel using the set of assays we developed demonstrates our ability to detect differences in their mechanism of action. Importantly, these assays will be very useful in high-throughput screening where highly potent pore-forming peptides can be selected based on their mechanism of action. PMID:22365969

  7. Compact contacting device

    NASA Technical Reports Server (NTRS)

    Acharya, Arun (Inventor); Gottzmann, Christian F. (Inventor); Lockett, Michael J. (Inventor); Schneider, James S. (Inventor); Victor, Richard A. (Inventor); Zawierucha, Robert (Inventor)

    1994-01-01

    An apparatus comprising a rotatable mass of structured packing for mass or heat transfer between two contacting fluids of different densities wherein the packing mass is made up of corrugated sheets of involute shape relative to the axis of the packing mass and form a logarithmic spiral curved counter to the direction of rotation.

  8. Structures and mechanism for the design of highly potent glucocorticoids.

    PubMed

    He, Yuanzheng; Yi, Wei; Suino-Powell, Kelly; Zhou, X Edward; Tolbert, W David; Tang, Xiaobo; Yang, Jing; Yang, Huaiyu; Shi, Jingjing; Hou, Li; Jiang, Hualiang; Melcher, Karsten; Xu, H Eric

    2014-06-01

    The evolution of glucocorticoid drugs was driven by the demand of lowering the unwanted side effects, while keeping the beneficial anti-inflammatory effects. Potency is an important aspect of this evolution as many undesirable side effects are associated with use of high-dose glucocorticoids. The side effects can be minimized by highly potent glucocorticoids that achieve the same treatment effects at lower doses. This demand propelled the continuous development of synthetic glucocorticoids with increased potencies, but the structural basis of their potencies is poorly understood. To determine the mechanisms underlying potency, we solved the X-ray structures of the glucocorticoid receptor (GR) ligand-binding domain (LBD) bound to its endogenous ligand, cortisol, which has relatively low potency, and a highly potent synthetic glucocorticoid, mometasone furoate (MF). The cortisol-bound GR LBD revealed that the flexibility of the C1-C2 single bond in the steroid A ring is primarily responsible for the low affinity of cortisol to GR. In contrast, we demonstrate that the very high potency of MF is achieved by its C-17? furoate group completely filling the ligand-binding pocket, thus providing additional anchor contacts for high-affinity binding. A single amino acid in the ligand-binding pocket, Q642, plays a discriminating role in ligand potency between MF and cortisol. Structure-based design led to synthesis of several novel glucocorticoids with much improved potency and efficacy. Together, these results reveal key structural mechanisms of glucocorticoid potency and provide a rational basis for developing novel highly potent glucocorticoids. PMID:24763108

  9. Contact Us

    Cancer.gov

    For more information, please contact: Office of Cancer Clinical Proteomics ResearchCenter for Strategic Scientific InitiativesOffice of the DirectorNational Cancer Institute31 Center Drive, MS 2580Bethesda, MD 20892-2580 Telephone: (301) 451-8883Email:

  10. Complete form and bring to Hawley Fitness Center, or mail to Janet Rochester, Dept AHS, Unit 1101. For information, contact Janet.Rochester@Uconn.edu, 6-5975.

    E-print Network

    Alpay, S. Pamir

    Complete form and bring to Hawley Fitness Center, or mail to Janet Rochester, Dept AHS, Unit 1101://cag.uconn.edu/ahs/hawley/ Class Size Limited! Are you ready for... Group Strength Training classes in Hawley Fitness Center conditioned fitness center in Hawley! Choose "The Basics" or "Advanced" levels Learn a variety of strength

  11. Formation Of Ohmic Gold Contacts On Epitaxial GaAs

    NASA Technical Reports Server (NTRS)

    Hecht, Michael H.; Bell, L. Doug; Kaiser, William J.

    1991-01-01

    New low-temperature procedure used to deposit ohmic gold contacts on gallium arsenide epitaxial films, forming ohmic electrical contacts. Keeping wafer in vacuum until metallization prevents formation of rectifying contacts.

  12. Medicare: Helpful Contacts

    MedlinePLUS

    ... are here: Home . Contacts Home Share Medicare Helpful Contacts Find Helpful Contacts for Organizations This Helpful Contacts tool will provide ... and learn more about related websites Download Helpful Contacts Database You have the option of downloading the ...

  13. Anilinotriazoles as potent gamma secretase modulators.

    PubMed

    Velter, Adriana I; Bischoff, François P; Berthelot, Didier; De Cleyn, Michel; Oehlrich, Daniel; Jaroskova, Libuse; Macdonald, Gregor; Minne, Garrett; Pieters, Serge; Rombouts, Frederik; Van Brandt, Sven; Van Roosbroeck, Yves; Surkyn, Michel; Trabanco, Andrés A; Tresadern, Gary; Wu, Tongfei; Borghys, Herman; Mercken, Marc; Masungi, Chantal; Gijsen, Harrie

    2014-12-15

    The design and synthesis of a novel series of potent gamma secretase modulators is described. Exploration of various spacer groups between the triazole ring and the aromatic appendix in 2 has led to anilinotriazole 28, which combined high in vitro and in vivo potency with an acceptable drug-like profile. PMID:25454273

  14. Three-dimensional hydrofacies assemblages in ice-contact/proximal sediments forming a heterogeneous `hybrid' hydrostratigraphic unit in central Illinois, USA

    NASA Astrophysics Data System (ADS)

    Atkinson, Lisa A.; Ross, Martin; Stumpf, Andrew J.

    2014-07-01

    Three-dimensional (3-D) hydrostratigraphic modelling of glacial sediment assemblages was undertaken as part of a groundwater study in central Illinois, USA. Sediments comprising these assemblages, informally referred to as the Glasford deglacial unit, form discontinuous sand-gravel layers including small aquifer zones, and fine-grained interstratified layers that may impede groundwater movement. This unit is stratigraphically above a regional aquitard overlying the important Mahomet aquifer. The study improves understanding of the internal stratigraphic architecture and hydrostratigraphic character of the unit. Data include descriptions of continuous cores, profiles of near-surface and downhole geophysical logs, and sediment descriptions from water well logs. Discrete bounding surfaces constructed using gOcad represent the main lithofacies assemblages forming a 3-D framework. The framework was further partitioned into a 3-D cellular grid for mapping the spatial distribution of fine- and coarse-grained facies. Hydraulic conductivity (K G) estimates were used to convert these lithofacies into hydrofacies. Medium- to coarse-grained hydrofacies (K G = 1.25 × 10-5 m/s) represent 46 % of the total volume, the remainder being fine-grained hydrofacies (K G = 3.01 × 10-8 m/s). The spatial pattern of these hydrofacies is highly heterogeneous, thus, designating the Glasford deglacial unit as an aquifer or aquitard would be conceptually misleading. The term "hybrid hydrostratigraphic unit" is introduced to better represent conceptually this type of unit in hydrostratigraphic models.

  15. Texas A&M Identity Services Data Request For help with completing this form see http://infrastructure.tamu.edu/identity/access/form_help.html or contact IT Infrastructure & Operations at

    E-print Network

    Texas A&M Identity Services Data Request For help with completing this form see http://infrastructure.tamu.edu/identity-support@tamu.edu, fax to 979.845.6090, or mail to Director, IT Infrastructure & Operations, c/o Identity Management items 9-12. 9 Name and description of application or service that will use Texas A&M Identity Services

  16. Terminal sialic acids on CD44 N-glycans can block hyaluronan binding by forming competing intramolecular contacts with arginine sidechains.

    PubMed

    Faller, Christina E; Guvench, Olgun

    2014-11-01

    Specific sugar residues and their linkages form the basis of molecular recognition for interactions of glycoproteins with other biomolecules. Seemingly small changes, like the addition of a single monosaccharide in the covalently attached glycan component of glycoproteins, can greatly affect these interactions. For instance, the sialic acid capping of glycans affects protein-ligand binding involved in cell-cell and cell-matrix interactions. CD44 is a single-pass transmembrane glycoprotein whose binding with its carbohydrate ligand hyaluronan (HA), an extracellular matrix component, mediates processes such as leukocyte homing, cell adhesion, and tumor metastasis. This binding is highly regulated by glycosylation of the N-terminal extracellular hyaluronan-binding domain (HABD); specifically, sialic acid capped N-glycans of HABD inhibit ligand binding. However, the molecular mechanism behind this sialic acid mediated regulation has remained unknown. Two of the five N-glycosyation sites of HABD have been previously identified as having the greatest inhibitory effect on HA binding, but only if the glycans contain terminal sialic acid residues. These two sites, Asn25 and Asn120, were chosen for in silico glycosylation in this study. Here, from extensive standard molecular dynamics simulations and biased simulations, we propose a molecular mechanism for this behavior based on spontaneously-formed charge-paired hydrogen bonding interactions between the negatively-charged sialic acid residues and positively-charged Arg sidechains known to be critically important for binding to HA, which itself is negatively charged. Such intramolecular hydrogen bonds would preclude associations critical to hyaluronan binding. This observation suggests how CD44 and related glycoprotein binding is regulated by sialylation as cellular environments fluctuate. PMID:25116630

  17. Contact dermatitis in children

    PubMed Central

    2010-01-01

    Contact dermatitis in pediatric population is a common but (previously) under recognized disease. It is usually divided into the allergic and the irritant forms. The diagnosis is usually obtained with the patch test technique after conducting a thorough medical history and careful physical examination but patch testing in infants may be particularly difficult, and false-positive reactions may occur. This study also provides an overview of the most common allergens in pediatric population and discusses various therapeutic modalities. PMID:20205907

  18. Sinterless Formation Of Contacts On Indium Phosphide

    NASA Technical Reports Server (NTRS)

    Weizer, Victor G.; Fatemi, Navid S.

    1995-01-01

    Improved technique makes it possible to form low-resistivity {nearly equal to 10(Sup-6) ohm cm(Sup2)} electrical contacts on indium phosphide semiconductor devices without damaging devices. Layer of AgP2 40 Angstrom thick deposited on InP before depositing metal contact. AgP2 interlayer sharply reduces contact resistance, without need for sintering.

  19. [Development of methodical principles and approval of new forms of contact with school children (ages 12-13 years) in carrying out preventive measures (results of a pilot study)].

    PubMed

    Mukhamedzhanova, R F; Suslova, E A; Gusev, G V; Chazova, L V; Dobo, S S

    1983-01-01

    The results of the screening and 1-year follow-up of pupils from two Moscow schools of general education (Moscow secondary schools) are presented. The program on preventive measures was conducted by using the playing forms of contact and influence, at one of the above schools (experimental school). Most of the adolescents of the experimental school (mean 80%) participated in the preventive measures. By the completion of the program the number of the participants increased up to 94%. A reliably significant increase in the education level on the problems about the adverse effects of smoking and beneficial effects of regular nutrition in adolescents of the experimental school was observed. The analysis of the results of the screening and follow-up of schoolchildren aged 12-13 years enables us to conclude that it is necessary to work out new criteria for the assessment of preventive measures among adolescents. PMID:6639762

  20. Quasi-quantum model of potentization.

    PubMed

    Molski, Marcin

    2011-10-01

    Analytical time-dependent functions describing the change of the concentration of the solvent S(t) and the homeopathic active substance A(t) during decimal and centesimal dilution are derived. The function S(t) is a special case of the West-Brown-Enquist curve describing ontogenic growth, the increase in concentration of the solvent during potentization resembles the growth of biological systems. It is demonstrated that the macroscopic S(t) function is the ground state solution of the microscopic non-local Horodecki-Feinberg equation for the time-dependent Hulthèn potential at the critical screening. In consequence potentization belongs to the class of quasi-quantum phenomena playing an important role both in biological systems and homeopathy. A comparison of the results predicted by the model proposed with the results of experiments on delayed luminescence of a homeopathic medicine is made. PMID:21962201

  1. Quasi-Quantum Model of Potentization

    E-print Network

    Marcin Molski

    2009-11-23

    Analytical time-dependent functions describing the change of the concentration of the solvent S(t) and the homeopathic active substance A(t) during the decimal and centesimal dilution are derived. The function S(t) is a special case of the West-Brown-Enquist curve describing the ontogenic growth, hence the increase in concentration of the solvent during potentization resembles the growth of biological systems. It is proven that the macroscopic S(t) function is the ground state solution of the microscopic non-local Horodecki-Feinberg equation for the time-dependent Hulthen potential at the critical screening. In consequence the potentization belongs to the class of quasi-quantum phenomena playing an important role both in the biological systems and homeopathy. A comparison of the model proposed with recently performed experiment on delayed luminescence of the homeopathic remedy will be also made.

  2. Quasi-Quantum Model of Potentization

    E-print Network

    Molski, Marcin

    2009-01-01

    Analytical time-dependent functions describing the change of the concentration of the solvent S(t) and the homeopathic active substance A(t) during the decimal and centesimal dilution are derived. The function S(t) is a special case of the West-Brown-Enquist curve describing the ontogenic growth, hence the increase in concentration of the solvent during potentization resembles the growth of biological systems. It is proven that the macroscopic S(t) function is the ground state solution of the microscopic non-local Horodecki-Feinberg equation for the time-dependent Hulthen potential at the critical screening. In consequence the potentization belongs to the class of quasi-quantum phenomena playing an important role both in the biological systems and homeopathy. A comparison of the model proposed with recently performed experiment on delayed luminescence of the homeopathic remedy will be also made.

  3. Contact Lens Risks

    MedlinePLUS

    ... Health and Consumer Devices Consumer Products Contact Lenses Contact Lens Risks Wearing contact lenses puts you at ... redness blurred vision swelling pain Serious Hazards of Contact Lenses Symptoms of eye irritation can indicate a ...

  4. Buying Contact Lenses

    MedlinePLUS

    ... and Consumer Devices Consumer Products Contact Lenses Buying Contact Lenses Contact lens sales are regulated by both the FDA ... Federal Trade Commission (FTC). Before you buy any contact lenses from someone other than your eye care ...

  5. Irritant contact dermatitis.

    PubMed

    Ale, Iris S; Maibach, Howard I

    2014-01-01

    Irritant contact dermatitis (ICD) is the most common form of contact dermatitis. It represents the cutaneous response to the toxic/physical effects of a wide variety of environmental agents. Nowadays, it is recognized that irritancy does not represent a single monomorphous entity but rather a complex biologic syndrome with diverse pathophysiology and clinical manifestations. The clinical presentation is highly variable depending on several factors, including properties and strength of the irritant, dose, duration and frequency of exposure, environmental factors, and skin susceptibility. The pathophysiological mechanism depends on activation of the innate immune system and involves skin barrier disruption, cellular changes, and release of proinflammatory mediators that directly recruit and activate T lymphocytes. The diagnosis of irritant contact dermatitis is often clinical, and involves a comprehensive history and examination, as well as the exclusion of allergic contact dermatitis with patch testing. Recent advances in understanding the pathogenesis as well as better awareness of the clinical significance of ICD will lead to a improved care for our patients. PMID:25274939

  6. EMERGENCY CONTACT CAMPUS DIRECTORY INFORMATION

    E-print Network

    Pilyugin, Sergei S.

    EMERGENCY CONTACT and CAMPUS DIRECTORY INFORMATION Please complete this form so that we have whether you wish to be included in the University of Florida Campus Directory. Submit completed form in the event of an emergency? (If yes, use space below) CAMPUS DIRECTORY Do you wish to have your home address

  7. Identification of a Potent Endothelium-Derived Angiogenic Factor

    PubMed Central

    Jankowski, Vera; Tölle, Markus; Tran, Thi Nguyet Anh; van der Giet, Markus; Schuchardt, Mirjam; Lehmann, Kerstin; Janke, Doreen; Flick, Burkhard; Ortiz, Alberto Arduan; Sanchez, Niño Maria Dolores; Tepel, Martin; Zidek, Walter; Jankowski, Joachim

    2013-01-01

    The secretion of angiogenic factors by vascular endothelial cells is one of the key mechanisms of angiogenesis. Here we report on the isolation of a new potent angiogenic factor, diuridine tetraphosphate (Up4U) from the secretome of human endothelial cells. The angiogenic effect of the endothelial secretome was partially reduced after incubation with alkaline phosphatase and abolished in the presence of suramin. In one fraction, purified to homogeneity by reversed phase and affinity chromatography, Up4U was identified by MALDI-LIFT-fragment-mass-spectrometry, enzymatic cleavage analysis and retention-time comparison. Beside a strong angiogenic effect on the yolk sac membrane and the developing rat embryo itself, Up4U increased the proliferation rate of endothelial cells and, in the presence of PDGF, of vascular smooth muscle cells. Up4U stimulated the migration rate of endothelial cells via P2Y2-receptors, increased the ability of endothelial cells to form capillary-like tubes and acts as a potent inducer of sprouting angiogenesis originating from gel-embedded EC spheroids. Endothelial cells released Up4U after stimulation with shear stress. Mean total plasma Up4U concentrations of healthy subjects (N?=?6) were sufficient to induce angiogenic and proliferative effects (1.34±0.26 nmol L-1). In conclusion, Up4U is a novel strong human endothelium-derived angiogenic factor. PMID:23922657

  8. Vapor-liquid contacting system

    SciTech Connect

    Butwell, K.F.; Sigmund, P.W.

    1981-10-27

    A vapor-liquid contacting tray is described wherein a perforated portion of the tray member forms an active surface area for vapor-liquid contact in the interior of the tray member. The active surface area portion of the tray member is circumscribed by an imperforate peripheral portion of the tray member with a width of from 0.05 to 0.35 times the radius of the tray. The disclosed tray provides upwardly directed laminar jetting of liquid over the tray perforation openings for high selectivity vapor-liquid contacting and has particular utility in the absorption of hydrogen sulfide from a gas mixture containing hydrogen sulfide and carbon dioxide.

  9. Chemistry and Biology of Deoxynyboquinone, a Potent Inducer of Cancer Cell Death

    E-print Network

    Hergenrother, Paul J.

    Chemistry and Biology of Deoxynyboquinone, a Potent Inducer of Cancer Cell Death Joseph S. Bair the mechanism by which DNQ induces death in cancer cells. DNQ was synthesized in seven linear steps through-oxidized by molecular oxygen, forming superoxide that induces cell death. Furthermore, global transcript profiling

  10. Semiconductor ohmic contact

    NASA Technical Reports Server (NTRS)

    Hawrylo, Frank Zygmunt (Inventor); Kressel, Henry (Inventor)

    1977-01-01

    A semiconductor device has one surface of P type conductivity material having a wide energy bandgap and a large crystal lattice parameter. Applied to the P type surface of the semiconductor device is a degenerate region of semiconductor material, preferably a group III-V semiconductor material, having a narrower energy bandgap. The degenerate region is doped with tin to increase the crystal lattice of the region to more closely approximate the crystal lattice of the one surface of the semiconductor device. The degenerate region is compensatingly doped with a P type conductivity modifier. An electrical contact is applied to one surface of the degenerate region forming an ohmic contact with the semiconductor device.

  11. 75 FR 49233 - Amendments to Form ADV

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-12

    ...each of the items in the form and the modifications we...its business address, contact information, Web site...furnish clients with a general contact number and email address instead of the name and contact information for the...

  12. Thioester derivatives of the natural product psammaplin A as potent histone deacetylase inhibitors

    PubMed Central

    Baud, Matthias G J; Leiser, Thomas; Petrucci, Vanessa; Gunaratnam, Mekala; Neidle, Stephen; Meyer-Almes, Franz-Josef

    2013-01-01

    Summary There has been significant interest in the bioactivity of the natural product psammaplin A, most recently as a potent and isoform selective HDAC inhibitor. Here we report our preliminary studies on thioester HDAC inhibitors derived from the active monomeric (thiol) form of psammaplin A, as a means to improve compound delivery into cells. We have discovered that such compounds exhibit both potent cytotoxicity and enzymatic inhibitory activity against recombinant HDAC1. The latter effect is surprising since previous SAR suggested that modification of the thiol functionality should detrimentally affect HDAC potency. We therefore also report our preliminary studies on the mechanism of action of this observed effect. PMID:23400330

  13. Thioester derivatives of the natural product psammaplin A as potent histone deacetylase inhibitors.

    PubMed

    Baud, Matthias G J; Leiser, Thomas; Petrucci, Vanessa; Gunaratnam, Mekala; Neidle, Stephen; Meyer-Almes, Franz-Josef; Fuchter, Matthew J

    2013-01-01

    There has been significant interest in the bioactivity of the natural product psammaplin A, most recently as a potent and isoform selective HDAC inhibitor. Here we report our preliminary studies on thioester HDAC inhibitors derived from the active monomeric (thiol) form of psammaplin A, as a means to improve compound delivery into cells. We have discovered that such compounds exhibit both potent cytotoxicity and enzymatic inhibitory activity against recombinant HDAC1. The latter effect is surprising since previous SAR suggested that modification of the thiol functionality should detrimentally affect HDAC potency. We therefore also report our preliminary studies on the mechanism of action of this observed effect. PMID:23400330

  14. Contact Information

    Cancer.gov

    Skip to Main Content at the National Institutes of Health | www.cancer.gov Print Page E-mail Page Search: Please wait while this form is being loaded.... Home Browse by Resource Type Browse by Area of Research Research Networks Funding Information About

  15. Hemin as a generic and potent protein misfolding inhibitor.

    PubMed

    Liu, Yanqin; Carver, John A; Ho, Lam H; Elias, Abigail K; Musgrave, Ian F; Pukala, Tara L

    2014-11-14

    Protein misfolding causes serious biological malfunction, resulting in diseases including Alzheimer's disease, Parkinson's disease and cataract. Molecules which inhibit protein misfolding are a promising avenue to explore as therapeutics for the treatment of these diseases. In the present study, thioflavin T fluorescence and transmission electron microscopy experiments demonstrated that hemin prevents amyloid fibril formation of kappa-casein, amyloid beta peptide and ?-synuclein by blocking ?-sheet structure assembly which is essential in fibril aggregation. Further, inhibition of fibril formation by hemin significantly reduces the cytotoxicity caused by fibrillar amyloid beta peptide in vitro. Interestingly, hemin degrades partially formed amyloid fibrils and prevents further aggregation to mature fibrils. Light scattering assay results revealed that hemin also prevents protein amorphous aggregation of alcohol dehydrogenase, catalase and ?s-crystallin. In summary, hemin is a potent agent which generically stabilises proteins against aggregation, and has potential as a key molecule for the development of therapeutics for protein misfolding diseases. PMID:25450392

  16. EDITORIAL: Close contact Close contact

    NASA Astrophysics Data System (ADS)

    Demming, Anna

    2010-07-01

    The development of scanning probe techniques, such as scanning tunnelling microscopy [1], has often been touted as the catalyst for the surge in activity and progress in nanoscale science and technology. Images of nanoscale structural detail have served as an invaluable investigative resource and continue to fascinate with the fantastical reality of an intricate nether world existing all around us, but hidden from view of the naked eye by a disparity in scale. As is so often the case, the invention of the scanning tunnelling microscope heralded far more than just a useful new apparatus, it demonstrated the scope for exploiting the subtleties of electronic contact. The shrinking of electronic devices has been a driving force for research into molecular electronics, in which an understanding of the nature of electronic contact at junctions is crucial. In response, the number of experimental techniques in molecular electronics has increased rapidly in recent years. Scanning tunnelling microscopes have been used to study electron transfer through molecular films on a conducting substrate, and the need to monitor the contact force of scanning tunnelling electrodes led to the use of atomic force microscopy probes coated in a conducting layer as studied by Cui and colleagues in Arizona [2]. In this issue a collaboration of researchers at Delft University and Leiden University in the Netherlands report a new device architecture for the independent mechanical and electrostatic tuning of nanoscale charge transport, which will enable thorough studies of molecular transport in the future [3]. Scanning probes can also be used to pattern surfaces, such as through spatially-localized Suzuki and Heck reactions in chemical scanning probe lithography. Mechanistic aspects of spatially confined Suzuki and Heck chemistry are also reported in this issue by researchers in Oxford [4]. All these developments in molecular electronics fabrication and characterization provide alternative means to produce nanoscale device elements, such as carbon nanotube transistors [5] and high-density memory crossbar circuits [6]. Recently, the use of scanning tunnelling microscopes has broached a new field of research, which is currently attracting enormous interest—single molecule detection. In issue 25 of Nanotechnology researchers in Houston reported unprecedented sensitivities using localized surface plasmon resonance shifts of gold bipyramids to detect concentrations of substances down to the single molecule level [7]. In issue 26 a collaboration of researchers from the US and Czech Republic describe a different approach, namely tunnelling recognition. In their topical review they describe hydrogen-bond mediated tunnelling and the associated experimental methods that facilitate the detection of single molecules in a tunnel junction using chemically functionalized electrodes [8]. The nanoworld depicted by scanning probe microgaphs over 20 years ago may have looked as extraterrestrial as any science fiction generated alien terrain, but though study and analysis these nano-landscapes have become significantly less alien territory. The work so far to unveil the intricacies of electronic contact has been a story of progress in investigating this new territory and manipulating the mechanisms that govern it to formulate new devices and delve deeper into phenomena at the nanoscale. References [1] Binning G, Rohrer H, Gerber Ch and Weibel E 1982 Phys. Rev. Lett. 49 57-61 [2] X D Cui, X Zarate, J Tomfohr, O F Sankey, A Primak, A L Moore, T A Moore, D Gust, G~Harris and S M Lindsay 2002 Nanotechnology 13 5-14 [3] Martin C A, van Ruitenbeek J M and van der Zant S J H 2010 Nanotechnology 21 265201 [4] Davis J J and Hanyu Y 2010 Nanotechnology 21 265302 [5] Tans S J, Verschueren A R M and Dekker C 1998 Nature 393 49-52 [6] Chen Y, Jung G-Y, Ohlberg D A A, Li X, Stewart D R, Jeppesen J O, Nielsen K A, Stoddart J F and Williams R S 2003 Nanotechnology 14 462-8 [7] Mayer K M, Hao F, Lee S, Nordlander P and Hafner J H 2010 Nanotechnology 21 255503 [8] Lindsay S, He J, Sank

  17. Can Contact Potentials Reliably Predict Stability of Proteins?

    E-print Network

    Khatun, Jainab

    Can Contact Potentials Reliably Predict Stability of Proteins? Jainab Khatun, Sagar D. Khare residues in proteins is the contact potential, which defines the effective free energy of a protein conformation by a set of amino acid contacts formed in this conformation. Finding a contact potential capable

  18. On the nature of tribological contact in automotive brakes

    Microsoft Academic Search

    Mikael Eriksson; Filip Bergman; Staffan Jacobson

    2002-01-01

    The tribological contact in automotive brakes involves dry sliding contact at high speeds and high contact forces. The commonly used organic binder-type brake pad friction materials are extremely inhomogeneous and exhibit very low bulk strengths. Despite the low strength, the specific contact surfaces that form during the use render the pads very good friction and wear characteristics. This paper gives

  19. A potent peptidomimetic inhibitor of botulinum neurotoxin serotype A has a very different conformation than SNAP-25 substrate

    PubMed Central

    Zuniga, Jorge E.; Schmidt, James J.; Fenn, Timothy; Burnett, James C.; Araç, Demet; Gussio, Rick; Stafford, Robert G.; Badie, Shirin S.; Bavari, Sina; Brunger, Axel T.

    2008-01-01

    Botulinum neurotoxin serotype A is the most lethal of all known toxins. Here, we report the crystal structure, along with SAR data, of the zinc metalloprotease domain of BoNT/A bound to a potent peptidomimetic inhibitor (Ki = 41 nM) that resembles the local sequence of the SNAP-25 substrate. Surprisingly, the inhibitor adopts a helical conformation around the cleavage site, in contrast to the extended conformation of the native substrate. The backbone of the inhibitor’s P1 residue displaces the putative catalytic water molecule and concomitantly interacts with the ‘proton shuttle’ E224. This mechanism of inhibition is aided by residue contacts in the conserved S1? pocket of the substrate binding cleft, and the induction of new hydrophobic pockets, which are not present in the apo form, especially for the P2? residue of the inhibitor. Our inhibitor is specific for BoNT/A as it does not inhibit other BoNT serotypes or thermolysin. PMID:18940613

  20. Contact Lens Care

    MedlinePLUS

    ... sell contact lenses. Make sure your prescription includes: Your name Date of your eye exam Date you received ... measurements The contact lens brand name and material Your doctor’s name and contact information Watch out! Make sure you ...

  1. Buying Cosmetic Contact Lenses?

    MedlinePLUS

    ... Getting Your Prescription Should Be Easy What Are Cosmetic Contacts? Whether you're planning to cap off ... color from blue to violet for the day, cosmetic contactscontact lenses meant to change the way ...

  2. Novel cyanocombretastatins as potent tubulin polymerisation inhibitors.

    PubMed

    Jalily, Pouria H; Hadfield, John A; Hirst, Nicholas; Rossington, Steven B

    2012-11-01

    A series of novel cyanocombretastatins bearing a 3,4,5-trimethoxyphenyl moiety combined with a variety of substituted phenyl rings, were synthesised and their antitumour activity was evaluated. The Z-cyanocombretastatins were synthesised in a one-step protocol in high purity and yield. Fluoro, bromo, iodo, and derivatives with boronic acid and an ethyne function at meta position of the B ring were synthesised. In vitro MTT bioassays against human chronic myelogenous leukaemia (K562) and transfected breast adenocarcinoma (MDA NQO1) cell lines, revealed promising IC(50) inhibitory values in nanomolar range (<50 nM). Introduction of a nitrile function on the olefinic bond not only increased the cytotoxicity of the less active Z-isomers but rendered the analogues as moderate to potent inhibitors of tubulin polymerisation comparable to that of CA-4 (IC(50)=2.2 ?M). PMID:23010271

  3. Protein farnesyltransferase inhibitors exhibit potent antimalarial activity.

    PubMed

    Nallan, Laxman; Bauer, Kevin D; Bendale, Pravin; Rivas, Kasey; Yokoyama, Kohei; Hornéy, Carolyn P; Pendyala, Prakash Rao; Floyd, David; Lombardo, Louis J; Williams, David K; Hamilton, Andrew; Sebti, Said; Windsor, William T; Weber, Patricia C; Buckner, Frederick S; Chakrabarti, Debopam; Gelb, Michael H; Van Voorhis, Wesley C

    2005-06-01

    New therapeutics to combat malaria are desperately needed. Here we show that the enzyme protein farnesyltransferase (PFT) from the malaria parasite Plasmodium falciparum (P. falciparum) is an ideal drug target. PFT inhibitors (PFTIs) are well tolerated in man, but are highly cytotoxic to P. falciparum. Because of their anticancer properties, PFTIs comprise a highly developed class of compounds. PFTIs are ideal for the rapid development of antimalarials, allowing "piggy-backing" on previously garnered information. Low nanomolar concentrations of tetrahydroquinoline (THQ)-based PFTIs inhibit P. falciparum PFT and are cytotoxic to cultured parasites. Biochemical studies suggest inhibition of parasite PFT as the mode of THQ cytotoxicity. Studies with malaria-infected mice show that THQ PFTIs dramatically reduce parasitemia and lead to parasite eradication in the majority of animals. These studies validate P. falciparum PFT as a target for the development of antimalarials and describe a potent new class of THQ PFTIs with antimalaria activity. PMID:15916422

  4. Orally Bioavailable Potent Soluble Epoxide Hydrolase Inhibitors

    PubMed Central

    Hwang, Sung Hee; Tsai, Hsing-Ju; Liu, Jun-Yan; Morisseau, Christophe; Hammock, Bruce D.

    2008-01-01

    A series of N,N?-disubstituted ureas having a conformationally restricted cis- or trans-1,4-cyclohexane ? to the urea were prepared and tested as soluble epoxide hydrolase (sEH) inhibitors. This series of compounds showed low nanomolar to picomolar activities against recombinant human sEH. Both isomers showed similar potencies, but the trans isomers were more metabolically stable in human hepatic microsomes. Furthermore, these new potent inhibitors show a greater metabolic stability in vivo than previously described sEH inhibitors. We demonstrated that trans-4-[4-(3-adamantan-1-ylureido)cyclohexyloxy]benzoic acid 13g (t-AUCB, IC50 = 1.3 ± 0.05 nM) had excellent oral bioavailability (98%, n = 2) and blood area under the curve in dogs and was effective in vivo to treat hypotension in lipopolysaccharide challenged murine models. PMID:17616115

  5. Chord diagrams, contact-topological quantum field theory, and contact categories

    NASA Astrophysics Data System (ADS)

    Mathews, Daniel

    In this thesis we study some interesting mathematics arising at the intersection of the studies of contact topology and sutured Floer homology. Although this work was originally motivated by the study of contact elements in sutured Floer homology, we also obtain results in pure contact topology. We consider contact elements in the sutured Floer homology of solid tori, as part of the (1+1)-dimensional topological quantum field theory defined by Honda-Kazez-Matic. We find that the Z2 sutured Floer homology of solid tori with longitudinal sutures forms a "categorification of Pascal's triangle", a triangle of vector spaces. Contact structures on solid tori with longitudinal sutures correspond bijectively to chord diagrams, which are sets of disjoint properly embedded arcs in the disc; these may in turn be identified with contact elements. The contact elements form distinguished subsets of the vector spaces in the categorified Pascal's triangle, of order given by the Narayana numbers. We find natural "creation and annihilation operators" which allow us to define a QFT-type basis of each SFH vector space, consisting of contact elements. We show that sutured Floer homology in this case reduces to the combinatorics of chord diagrams. We prove that contact elements are in bijective correspondence with comparable pairs of basis elements with respect to a certain partial order, and in a natural and explicit way. We also prove numerous results about the structure of contact elements and investigate various algebraic structures which arise. Our main theorem, describing how contact elements lie in sutured Floer homology, has a purely combinatorial interpretation, as a statement about chords on discs subject to a certain surgery and a single addition relation. The algebraic and combinatorial structures which naturally arise in this description have intrinsic contact-topological meaning. In particular, the QFT-type basis of sutured Floer homology, and its partial order, have a natural interpretation in pure contact topology, related to the contact category of a disc: the partial order enables us to tell when the sutured solid cylinder obtained by "stacking" two chord diagrams has a tight contact structure. This leads us to extend Honda's notion of contact category to a "bounded" contact category, containing chord diagrams and contact structures which occur within a given contact solid cylinder. We compute this bounded contact category in certain cases. Moreover, the decomposition of a contact element into basis elements naturally gives a triple of contact structures on solid cylinders which we regard as a type of "distinguished triangle" in the contact category. We also use the algebraic structures arising among contact elements to extend the notion of contact category to a 2-category.

  6. For questions, contact the Rice Alliance at 713.348.3443 Submit form with payment details via fax at 713.348.3110 or mail to: Rice Alliance for Technology and Entrepreneurship Rice University MS-531 P.O. Box 2932 Houston, TX 77252-2932

    E-print Network

    For questions, contact the Rice Alliance at 713.348.3443 · Submit form with payment details via fax at 713.348.3110 or mail to: Rice Alliance for Technology and Entrepreneurship · Rice University · MS-531 · P.O. Box 2932 · Houston, TX · 77252-2932 Rice Alliance Annual Corporate Underwriter Program 2012

  7. Contact tracing and disease control

    Microsoft Academic Search

    Ken T. D. Eames; Matt J. Keeling

    2003-01-01

    Contact tracing, followed by treatment or isolation, is a key control measure in the battle against infectious diseases. It is an extreme form of locally targeted control, and as such has the potential to be highly efficient when dealing with low numbers of cases. For this reason it is frequently used to combat sexually transmitted diseases and new invading pathogens.

  8. Contact with Wear or Adhesion

    NASA Astrophysics Data System (ADS)

    Shillor, Meir; Sofonea, Mircea; Telega, Józef Joachim

    In this chapter we present results on models of frictional contact when the wear of the contacting surfaces is taken into account. The importance of the control and minimization of the wear of industrial parts and components cannot be overstated, and therefore, effective models for the prediction of wear in industrial settings are indispensable to the design engineer. We describe three problems of contact with wear for viscoelastic materials of the form (6.4.3). The wear is described by the differential form of Archards law and the contact is bilateral in Sect. 11.1 and with the normal compliance condition in Sect. 11.2. It is assumed, in both cases, that the wear particles or debris are removed from the system as quickly as they are being produced. This is the case in many settings, and one of the functions of engine oil is to remove such debris. However, in other settings wear particles remain and migrate or diffuse in the gap between the contacting surfaces causing further wear and deterioration of the lubricant or of the surfaces themselves. We describe this in Sect. 11.3, where the diffusion equation is used for the debris.

  9. Large deformation contact mechanics of long rectangular membranes. I. Adhesionless contact

    PubMed Central

    Srivastava, Abhishek; Hui, Chung-Yuen

    2013-01-01

    In part I of this work, we study adhesionless contact of a long rectangular elastic membrane with a rigid substrate. Our model is based on finite strain theory and is valid for arbitrarily large deformations. Both frictionless and no-slip contact conditions are considered. Exact closed form solutions are obtained for frictionless contact. For small contact, the differences between these two contact conditions are small. However, significant differences occur for large contacts. For example, frictionless contact predicts a maximum pressure (and contact region) beyond which there is no solution; while the no-slip model places no restriction on both quantities. The effect of adhesion will be considered in part II of this work. PMID:24353471

  10. Hydrodynamic lubrication in fully plastic asperity contacts

    NASA Astrophysics Data System (ADS)

    Zhang, Yongbin

    2012-01-01

    A line contact inlet zone analysis is carried out for the hydrodynamic lubrication in a fully plastic asperity contact. A governing equation of the central film thickness i.e. the film thickness in the fully plastic contact area is derived. An equation predicting this film thickness is also derived. It is found that for the fully plastic contact, under relatively light loads the prediction accuracy for the central film thickness is good, while at the load heavy enough the prediction equation greatly overestimates the central film thickness and the central film thickness solved from the analytical governing equation is significantly low showing the asperity in boundary layer lubrication. For the fully plastic contact, the central film thickness is nearly half of that obtained based on the elastic contact assumption for relatively light loads or even lower for heavier loads. The hydrodynamic lubrication is found difficult to form in the fully plastic asperity contact for the carried load heavy enough or the significantly low sliding speed between the asperities. To achieve a high hydrodynamic lubrication film thickness in the fully plastic asperity contact it is recommended to employ a high sliding speed or a high fluid viscosity. However, in the fully plastic asperity contact, the potential hydrodynamic load-carrying capacity is limited and much smaller than that based on the elastic contact assumption or predicted by conventional line contact elasto-hydrodynamic lubrication theory.

  11. Commons Request Form Organization Information

    E-print Network

    : _______________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ Space Requested (select one): _____ Kafadar Commons _____ Stratton Commons For IM fields, please contact Recreational Sports to reserve space; For athletic fields, please contact Athletics office to reserve space Date Please return form to Student Life Office, SC 218 Contact AJ Lauer 303-273-3353 alauer

  12. Graded contact manifolds and contact Courant algebroids

    E-print Network

    Janusz Grabowski

    2013-02-06

    We develop a systematic approach to contact and Jacobi structures on graded supermanifolds. In this framework, contact structures are interpreted as symplectic principal GL(1,R)-bundles. Gradings compatible with the GL(1,R)-action lead to the concept of a graded contact manifold, in particular a linear (more generally, n-linear) contact structure. Linear contact structures are proven to be exactly the canonical contact structures on first jets of line bundles. They provide linear Kirillov (or Jacobi) brackets and give rise to the concept of a Kirillov algebroid, an analog of a Lie algebroid, for which the corresponding cohomology operator is represented not by a vector field (de Rham derivative) but a first-order differential operator. It is shown that one can view Kirillov or Jacobi brackets as homological Hamiltonians on linear contact manifolds. Contact manifolds of degree 2 are studied, as well as contact analogs of Courant algebroids. We define lifting procedures that provide us with constructions of canonical examples of the structures in question.

  13. Potent effects of dioscin against liver fibrosis

    PubMed Central

    Zhang, Xiaoling; Han, Xu; Yin, Lianhong; Xu, Lina; Qi, Yan; Xu, Youwei; Sun, Huijun; Lin, Yuan; Liu, Kexin; Peng, Jinyong

    2015-01-01

    We previously reported the promising effects of dioscin against liver injury, but its effect on liver fibrosis remains unknown. The present work investigated the activities of dioscin against liver fibrosis and the underlying molecular mechanisms. Dioscin effectively inhibited the cell viabilities of HSC-T6, LX-2 and primary rat hepatic stellate cells (HSCs), but not hepatocytes. Furthermore, dioscin markedly increased peroxisome proliferator activated receptor-? (PPAR-?) expression and significantly reduced a-smooth muscle actin (?-SMA), transforming growth factor-?1 (TGF-?1), collagen ?1 (I) (COL1A1) and collagen ?1 (III) (COL3A1) levels in vitro. Notably, dioscin inhibited HSCs activation and induced apoptosis in activated HSCs. In vivo, dioscin significantly improved body weight and hydroxylproline, laminin, ?-SMA, TGF-?1, COL1A1 and COL3A1 levels, which were confirmed by histopathological assays. Dioscin facilitated matrix degradation, and exhibited hepatoprotective effects through the attenuation of oxidative stress and inflammation, in addition to exerting anti-fibrotic effects through the modulation of the TGF-?1/Smad, Wnt/?-catenin, mitogen-activated protein kinase (MAPK) and mitochondrial signaling pathways, which triggered the senescence of activated HSCs. In conclusion, dioscin exhibited potent effects against liver fibrosis through the modulation of multiple targets and signaling pathways and should be developed as a novel candidate for the treatment of liver fibrosis in the future. PMID:25853178

  14. Ohmic contacts to compound semiconductor transistors

    NASA Astrophysics Data System (ADS)

    Dormaier, Robert A., III

    This thesis addresses Ohmic contacts to InAlSb/InAs high electron mobility transistor (HEMT) heterostructures and InGaAs epilayers. Palladium-based contacts provide very low contact resistance to both materials, which helps minimize parasitic resistances in transistors. For Pd/Pt/Au and Pd/Ru/Au contacts to the HEMTs, lower contact resistances are correlated with increasing reaction between Pd (and Pt) and the semiconductor during annealing and aging at 175--200°C for 3 h or 1 week. Voids form in the Pt diffusion barrier layer when Pd/Pt/Au contacts are aged 1 week at 175°C and grow larger during aging at higher temperatures. The increase in contact resistance of Pd/Pt/Au contacts by more than a factor of 2 after a 1 week, 225°C aging cycle is discussed in light of the interfacial reactions that occur during aging. Alternatively, no reaction is observed between the Ru diffusion barrier and the semiconductor in Pd/Ru/Au contacts, which yield a contact resistance of 0.05 +/- 0.01 O mm after a 1 week, 225°C aging cycle that is comparable to the minimum value of 0.03 +/- 0.01 O mm yielded by Pd/Pt/Au contacts. Measurement artifacts associated with the transfer length method are identified and probe placements that mitigate the artifacts are used to reliably examine low specific contact resistance (rhoc) Ohmic contacts to InGaAs. Standardization of surface preparation procedures and a low relative humidity processing environment yield very low rhoc contacts to n-InGaAs. Examinations of wet etchants for oxide removal after UV/O 3 treatment demonstrate that BOE- and NH4OH-based etchants yield much lower rhoc values than HCl (5.0+/-0.6x10-9 and 5.7+/-1.4x10-9 versus 1.7+/-0.1x10 -8 O cm2). Palladium and Pt yield lower as-deposited and annealed rhoc values than Mo-, Ti-, and TiW-based contacts. Furthermore, collimated sputter-deposited contacts yield lower rho c values than electron-beam evaporated contacts. Several phenomena that may be responsible for the low rhoc values of Pd-based contacts are proposed and discussed. Ohmic contacts to p-InGaAs with a thin n-InGaAs cap are also examined: Pd/Ti multilayer contacts yield rhoc < 1x10-8 O cm2 after 2 hr at 270°C.

  15. 40 CFR 463.10 - Applicability; description of the contact cooling and heating water subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Applicability; description of the contact cooling and heating water subcategory. 463...FORMING POINT SOURCE CATEGORY Contact Cooling and Heating Water Subcategory § 463...Applicability; description of the contact cooling and heating water subcategory....

  16. 40 CFR 463.10 - Applicability; description of the contact cooling and heating water subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Applicability; description of the contact cooling and heating water subcategory. 463...FORMING POINT SOURCE CATEGORY Contact Cooling and Heating Water Subcategory § 463...Applicability; description of the contact cooling and heating water subcategory....

  17. 40 CFR 463.10 - Applicability; description of the contact cooling and heating water subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Applicability; description of the contact cooling and heating water subcategory. 463...FORMING POINT SOURCE CATEGORY Contact Cooling and Heating Water Subcategory § 463...Applicability; description of the contact cooling and heating water subcategory....

  18. 76 FR 33031 - Agency Information Collection (Request for Contact Information) Activity Under OMB Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-07

    ...Agency Information Collection (Request for Contact Information) Activity Under OMB Review...correspondence. FOR FURTHER INFORMATION CONTACT: Denise McLamb, Enterprise Records Service...SUPPLEMENTARY INFORMATION: Title: Request for Contact Information, VA Form 21-30. OMB...

  19. Contact mechanics: contact area and interfacial separation from small contact to full contact

    E-print Network

    C. Yang; B. N. J. Persson

    2008-03-28

    We present a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. The numerical calculations mainly focus on the contact area and the interfacial separation from small contact (low load) to full contact (high load). For small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load. For high load the contact area approaches the nominal contact area (i.e., complete contact), and the interfacial separation approaches zero. The numerical results have been compared with analytical theory and experimental results. They are in good agreement with each other. The present findings may be very important for soft solids, e.g., rubber, or for very smooth surfaces, where complete contact can be reached at moderate high loads without plastic deformation of the solids.

  20. College Timetable Representatives College Contact Contact Details

    E-print Network

    Harman, Neal.A.

    College Timetable Representatives College Contact Contact Details Adult Continuing Education Fran Lloyd F.J.Lloyd@swansea.ac.uk College of Arts & Humanities Ruth Lake R.Lake@swansea.ac.uk College of Engineering Tracey Bailey T.Bailey@swansea.ac.uk College of Human & Health Science SHSRoom

  1. Herschel and Planck contacts STFC contact

    E-print Network

    Herschel and Planck contacts STFC contact Richard Holdaway Director STFC Space Science Director of Space Science & Exploration Tel: (0)1793 44 2174 mobile: 07901 514969 david. Christine Brockley-Blatt MSSL SPIRE Project Manager University College London Mullard Space Science

  2. Hazardous Materials Alert Departmental Contact(s)

    E-print Network

    Hickman, Mark

    Hazardous Materials Alert Departmental Contact(s): Name ___________________________________________________________________________________ Hazardous Materials Alert If the release of a hazardous chemical or gas is affecting people in your areaVATE If it is a "gAs" or "HAzArDOUs MATEriAl AlErT", shout a warning, pass the alarm by word of mouth. If able

  3. Sifuvirtide, a potent HIV fusion inhibitor peptide

    SciTech Connect

    Wang, Rui-Rui; Yang, Liu-Meng; Wang, Yun-Hua [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China)] [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China); Pang, Wei [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China) [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China); Department of Molecular Virology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080 (China); Tam, Siu-Cheung [Department of Physiology, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China)] [Department of Physiology, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China); Tien, Po [Department of Molecular Virology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080 (China)] [Department of Molecular Virology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080 (China); Zheng, Yong-Tang, E-mail: zhengyt@mail.kiz.ac.cn [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China)] [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China)

    2009-05-08

    Enfuvirtide (ENF) is currently the only FDA approved HIV fusion inhibitor in clinical use. Searching for more drugs in this category with higher efficacy and lower toxicity seems to be a logical next step. In line with this objective, a synthetic peptide with 36 amino acid residues, called Sifuvirtide (SFT), was designed based on the crystal structure of gp41. In this study, we show that SFT is a potent anti-HIV agent with relatively low cytotoxicity. SFT was found to inhibit replication of all tested HIV strains. The effective concentrations that inhibited 50% viral replication (EC{sub 50}), as determined in all tested strains, were either comparable or lower than benchmark values derived from well-known anti-HIV drugs like ENF or AZT, while the cytotoxic concentrations causing 50% cell death (CC{sub 50}) were relatively high, rendering it an ideal anti-HIV agent. A GST-pull down assay was performed to confirm that SFT is a fusion inhibitor. Furthermore, the activity of SFT on other targets in the HIV life cycle was also investigated, and all assays showed negative results. To further understand the mechanism of action of HIV peptide inhibitors, resistant variants of HIV-1{sub IIIB} were derived by serial virus passage in the presence of increasing doses of SFT or ENF. The results showed that there was cross-resistance between SFT and ENF. In conclusion, SFT is an ideal anti-HIV agent with high potency and low cytotoxicity, but may exhibit a certain extent of cross-resistance with ENF.

  4. Of Contact Interactions and Colliders

    E-print Network

    Sacha Davidson; Sebastien Descotes-Genon; Patrice Verdier

    2014-10-17

    The hierarchy of scales which would allow dimension-six contact interactions to parametrise New Physics may not be verified at colliders. Instead, we explore the feasability and usefulness of parametrising the high-energy tail of distributions at the LHC using form factors. We focus on the process pp -> l+l- in the presence of t (or s)-channel New Physics, guess a form factor from the partonic cross-section, and attempt to use data to constrain its coefficients, and the coefficients to constrain models. We find that our choice of form factor decribes t-channel exchange better than a contact interaction, and the coefficients in a particular model can be obtained from the partonic cross-section. We estimate bounds on the coefficients by fitting the form factors to available data. For the parametrisation corresponding to the contact interaction approximation, our expected bounds on the scale $\\Lambda$ are within ~ 15% of the latest limits from the LHC experiments.

  5. Novel amino-?-lactam derivatives as potent cholesterol absorption inhibitors.

    PubMed

    Draži?, Tonko; Mol?anov, Krešimir; Sachdev, Vinay; Malnar, Martina; He?imovi?, Silva; Patankar, Jay V; Obrowsky, Sascha; Levak-Frank, Sanja; Habuš, Ivan; Kratky, Dagmar

    2014-11-24

    Two new trans-(3R,4R)-amino-?-lactam derivatives and their diastereoisomeric mixtures were synthesized as ezetimibe bioisosteres and tested in in vitro and in vivo experiments as novel ?-lactam cholesterol absorption inhibitors. Both compounds exhibited low cytotoxicity in MDCKII, hNPC1L1/MDCKII, and HepG2 cell lines and potent inhibitory effect in hNPC1L1/MDCKII cells. In addition, these compounds markedly reduced cholesterol absorption in mice, resulting in reduced cholesterol concentrations in plasma, liver, and intestine. We determined the crystal structure of one amino-?-lactam derivative to establish unambiguously both the absolute and relative configuration at the new stereogenic centre C17, which was assigned to be S. The pKa values for both compounds are 9.35, implying that the amino-?-lactam derivatives and their diastereoisomeric mixtures are in form of ammonium salt in blood and the intestine. The IC50 value for the diastereoisomeric mixture is 60 ?M. In vivo, it efficiently inhibited cholesterol absorption comparable to ezetimibe. PMID:25305716

  6. Novel amino-?-lactam derivatives as potent cholesterol absorption inhibitors

    PubMed Central

    Draži?, Tonko; Mol?anov, Krešimir; Sachdev, Vinay; Malnar, Martina; He?imovi?, Silva; Patankar, Jay V.; Obrowsky, Sascha; Levak-Frank, Sanja; Habuš, Ivan; Kratky, Dagmar

    2014-01-01

    Two new trans-(3R,4R)-amino-?-lactam derivatives and their diastereoisomeric mixtures were synthesized as ezetimibe bioisosteres and tested in in vitro and in vivo experiments as novel ?-lactam cholesterol absorption inhibitors. Both compounds exhibited low cytotoxicity in MDCKII, hNPC1L1/MDCKII, and HepG2 cell lines and potent inhibitory effect in hNPC1L1/MDCKII cells. In addition, these compounds markedly reduced cholesterol absorption in mice, resulting in reduced cholesterol concentrations in plasma, liver, and intestine. We determined the crystal structure of one amino-?-lactam derivative to establish unambiguously both the absolute and relative configuration at the new stereogenic centre C17, which was assigned to be S. The pKa values for both compounds are 9.35, implying that the amino-?-lactam derivatives and their diastereoisomeric mixtures are in form of ammonium salt in blood and the intestine. The IC50 value for the diastereoisomeric mixture is 60 ?M. In vivo, it efficiently inhibited cholesterol absorption comparable to ezetimibe. PMID:25305716

  7. Colored Contact Lens Dangers

    MedlinePLUS Videos and Cool Tools

    ... Consumer Alerts Colored Contact Lens Dangers Tweet Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During ... Eye Protection Eyesight Risks for Smokers Veterans & Eye Health More Lifestyle Topics > EyeSmart Tips Water & Contacts Don’ ...

  8. Glasses and Contact Lenses

    MedlinePLUS

    ... together the way they should. But eyeglasses or contact lenses, also called corrective lenses, can help most ... trouble, it's often a refractive problem. Glasses or contact lenses work so well because they can correct ...

  9. Contact Name: Originator

    E-print Network

    Contact Name: Originator: Faculty & Department Contact Telephone: DIRECT DEPOSIT BANKING: Pay Frequency: Monthly: Biweekly: PREVIOUS BANK INFORMATION Name of Bank: Address of Bank: (street name, city, postal code) 3-digit Institution Number: 5-Digit Branch Number: Account Number: NEW BANK

  10. Thermal contact resistance

    E-print Network

    Mikic, B. B.

    1966-01-01

    This work deals with phenomena of thermal resistance for metallic surfaces in contact. The main concern of the work is to develop reliable and practical methods for prediction of the thermal contact resistance for various ...

  11. Grants Management Contacts

    Cancer.gov

    Posted: April 2, 2015 Posted: April 2, 2015 Grants Management Contacts Please contact the grants management specialist assigned to your institution for questions regarding NCI grants. Institution Assigned Specialist FY 2015 3P Biotechnologies,

  12. Cosmic Contact Censorship

    E-print Network

    Pushkar Ganesh Vaidya

    2007-02-20

    Till date we have not made Contact with any Extraterrestrial civilizations. The Fermi Paradox remains a paradox - the Great Silence prevails. In the light of the Rare Earth hypothesis, it seems that advanced life is exceedingly rare in the universe. Also, if there does exist some Extraterrestrial civilizations then still achieving Contact is extremely difficult as the very nature of the universe discourages Contact. It's as if there is a Cosmic Contact Censorship in place.

  13. ATBC Study - Questionnaires and Forms

    Cancer.gov

    Skip to Main Content Home Contact Us Links Study Details Questionnaires & Forms Current Projects ATBC Study Bibliography Study Investigators & Collaborators Proposal Review & Collaboration Research Consortium Projects Questionnaires & Forms Baseline

  14. Contact solution algorithms

    NASA Technical Reports Server (NTRS)

    Tielking, John T.

    1989-01-01

    Two algorithms for obtaining static contact solutions are described in this presentation. Although they were derived for contact problems involving specific structures (a tire and a solid rubber cylinder), they are sufficiently general to be applied to other shell-of-revolution and solid-body contact problems. The shell-of-revolution contact algorithm is a method of obtaining a point load influence coefficient matrix for the portion of shell surface that is expected to carry a contact load. If the shell is sufficiently linear with respect to contact loading, a single influence coefficient matrix can be used to obtain a good approximation of the contact pressure distribution. Otherwise, the matrix will be updated to reflect nonlinear load-deflection behavior. The solid-body contact algorithm utilizes a Lagrange multiplier to include the contact constraint in a potential energy functional. The solution is found by applying the principle of minimum potential energy. The Lagrange multiplier is identified as the contact load resultant for a specific deflection. At present, only frictionless contact solutions have been obtained with these algorithms. A sliding tread element has been developed to calculate friction shear force in the contact region of the rolling shell-of-revolution tire model.

  15. Lab Contact: After Hours Phone

    E-print Network

    Shull, Kenneth R.

    Lab Contact: Lab Group: After Hours Phone: Lab Contact: Lab Group: After Hours Phone: Lab Contact: Lab Group: After Hours Phone: Emergency Response Personnel must be able to contact a knowledgeable party for information about the lab. Lab Contacts Lab Contact: Lab Group: After Hours Phone: Lab Contact

  16. Structures of Potent Selective Peptide Mimetics Bound to Carboxypeptidase B

    SciTech Connect

    Adler, M.; Buckman, B.; Bryant, J.; Chang, Z.; Chu, K.; Emayan, K.; Hrvatin, P.; Islam, I.; Morser, J.; Sukovich, D.; West, C.; Yuan, S.; Whitlow, M.

    2009-05-11

    This article reports the crystal structures of inhibitors of the functional form of thrombin-activatable fibrinolysis inhibitor (TAFIa). In vivo experiments indicate that selective inhibitors of TAFIa would be useful in the treatment of heart attacks. Since TAFIa rapidly degrades in solution, the homologous protein porcine pancreatic carboxypeptidase B (pp-CpB) was used in these crystallography studies. Both TAFIa and pp-CpB are zinc-based exopeptidases that are specific for basic residues. The final development candidate, BX 528, is a potent inhibitor of TAFIa (2 nM) and has almost no measurable effect on the major selectivity target, carboxypeptidase N. BX 528 was designed to mimic the tripeptide Phe-Val-Lys. A sulfonamide replaces the Phe-Val amide bond and a phosphinate connects the Val and Lys groups. The phosphinate also chelates the active-site zinc. The electrostatic interactions with the protein mimic those of the natural substrate. The primary amine in BX 528 forms a salt bridge to Asp255 at the base of the S1 pocket. The carboxylic acid interacts with Arg145 and the sulfonamide is hydrogen bonded to Arg71. Isopropyl and phenyl groups replace the side chains of Val and Phe, respectively. A series of structures are presented here that illustrate the evolution of BX 528 from thiol-based inhibitors that mimic a free C-terminal arginine. The first step in development was the replacement of the thiol with a phosphinate. This caused a precipitous drop in binding affinity. Potency was reclaimed by extending the inhibitors into the downstream binding sites for the natural substrate.

  17. Contact lens in keratoconus

    PubMed Central

    Rathi, Varsha M; Mandathara, Preeji S; Dumpati, Srikanth

    2013-01-01

    Contact lenses are required for the visual improvement in patients with keratoconus. Various contact lens options, such as rigid gas permeable (RGP) lenses, soft and soft toric lenses, piggy back contact lenses (PBCL), hybrid lenses and scleral lenses are availble. This article discusses about selection of a lens depending on the type of keratoconus and the fitting philosophies of various contact lenses including the starting trial lens. A Medline search was carried out for articles in the English language with the keywords keratoconus and various contact lenses such as Rose k lens, RGP lens, hybrid lens, scleral lens and PBCL. PMID:23925325

  18. Contact lens in keratoconus.

    PubMed

    Rathi, Varsha M; Mandathara, Preeji S; Dumpati, Srikanth

    2013-08-01

    Contact lenses are required for the visual improvement in patients with keratoconus. Various contact lens options, such as rigid gas permeable (RGP) lenses, soft and soft toric lenses, piggy back contact lenses (PBCL), hybrid lenses and scleral lenses are availble. This article discusses about selection of a lens depending on the type of keratoconus and the fitting philosophies of various contact lenses including the starting trial lens. A Medline search was carried out for articles in the English language with the keywords keratoconus and various contact lenses such as Rose k lens, RGP lens, hybrid lens, scleral lens and PBCL. PMID:23925325

  19. Azachalcones: A new class of potent polyphenol oxidase inhibitors.

    PubMed

    Radhakrishnan, Sini Karanayil; Shimmon, Ronald Gibrial; Conn, Costa; Baker, Anthony T

    2015-04-15

    A library of potent inhibitors of polyphenol oxidase and their structure activity relationships are described. Azachalcone derivatives were synthesized and tested for their tyrosinase inhibitory activity. Their inhibitory activities on mushroom tyrosinase using l-DOPA as a substrate were investigated. Two compounds that are the reduction congeners of the pyridinyl azachalcones strongly inhibited the enzyme activity and were more potent than the positive control kojic acid. PMID:25782744

  20. BISON Contact Improvements CASL FY14 Report

    SciTech Connect

    B. W. Spencer; J. D. Hales; D. R. Gaston; D. A. Karpeev; R. L. Williamson; S. R. Novascone; D. M. Perez; R. J. Gardner; K. A. Gamble

    2014-09-01

    The BISON code is the foundation for multiple fuel performance modeling efforts, and is cur- rently under heavy development. For a variety of fuel forms, the effects of heat conduction across a gap and mechanical contact between components of a fuel system are very significant. It is thus critical that BISON have robust capabilities for enforcement of thermal and mechanical contact. BISON’s solver robustness has generally been quite good before mechanical contact between the fuel and cladding occurs, but there have been significant challenges obtaining converged so- lutions once that contact occurs and the solver begins to enforce mechanical contact constraints. During the current year, significant development effort has been focused on the enforcement of mechanical contact to provide improved solution robustness. In addition to this work to improve mechanical contact robustness, an investigation into ques- tionable results attributable to thermal contact has been performed. This investigation found that the order of integration typically used on the surfaces involved in thermal contact was not suffi- ciently high. To address this problem, a new option was provided to permit the use of a different integration order for surfaces, and new usage recommendations were provided.

  1. Dicationic bis(9-methylphenazine-1-carboxamides): relationships between biological activity and linker chain structure for a series of potent topoisomerase targeted anticancer drugs.

    PubMed

    Gamage, S A; Spicer, J A; Finlay, G J; Stewart, A J; Charlton, P; Baguley, B C; Denny, W A

    2001-04-26

    Bis(9-methylphenazine-1-carboxamides) joined by a variety of dicationic (CH(2))(n)()NR(CH(2))(m)NR(CH(2))(n) linkers of varying length (carboxamide N-N distances from 11.0 to 18.4 A) and rigidity were prepared by reaction of 9-methylphenazine-1-carboxylic acid imidazolide with the appropriate polyamines. The compounds were evaluated for growth inhibitory properties in P388 leukemia, Lewis lung carcinoma, and wild-type (JL(C)) and mutant (JL(A) and JL(D)) forms of human Jurkat leukemia with low levels of topoisomerase II (topo II). The compounds all had IC(50) ratios of <1 in the resistant Jurkat lines, consistent with topo II inhibition not being the primary mechanism of action. Analogues joined by an (CH(2))(2)NR(CH(2))(2)NR(CH(2))(2) linker were extremely potent cytotoxins, with selectivity toward the human cell lines, but absolute potencies declined sharply from R = H through R = Me to R = Pr and Bu. In contrast, (CH(2))(2)NR(CH(2))(3)NR(CH(2))(2) compounds showed reverse effects, with the R = Me analogue being more potent than the R = H one as well as being the most potent in the series [IC(50) in JL(C) cells 0.08 nM; superior to that for the clinical bis(naphthalimide) LU 79553]. Overall, the IC(50)s of analogues with linker chains (CH(2))(n)NH(CH(2))(m)NH(CH(2))(n) were inversely proportional to linker length. Constraining the rigidity of the linker chain by incorporating a piperazine ring did not decrease potency significantly. A representative compound bound tightly to DNA with high selectivity for GC sites, compatible with recent work suggesting that compounds of this type place their side chains in the major groove, making specific contacts with guanine bases. Representative compounds were susceptible to transport mediated resistance, being much less effective in cells that overexpressed P-glycoprotein. Overall the results suggest these compounds have a similar mode of action, mediated primarily by poisoning of topo I (possibly with some involvement of topo II). The bis(9-methylphenazine-1-carboxamides) show very high in vitro growth inhibitory potencies compared to their monomeric analogues. Two compounds showed in vivo activity in murine colon 38 syngeneic and HT29 human colon tumor xenograft models using intraperitoneal dosing. PMID:11311063

  2. Contact Dermatitis: Signs and Symptoms

    MedlinePLUS

    ... treatments A - D Contact dermatitis Signs and symptoms Contact dermatitis: Signs and symptoms Allergic contact dermatitis : Testing ... these symptoms, you need immediate medical care. Allergic contact dermatitis This skin condition occurs when you have ...

  3. Contact changes near jamming

    NASA Astrophysics Data System (ADS)

    van Deen, Merlijn S.; Simon, Johannes; Zeravcic, Zorana; Dagois-Bohy, Simon; Tighe, Brian P.; van Hecke, Martin

    2014-08-01

    We probe the onset and effect of contact changes in soft harmonic particle packings which are sheared quasistatically. We find that the first contact changes are the creation or breaking of contacts on a single particle. We characterize the critical strain, statistics of breaking versus making a contact, and ratio of shear modulus before and after such events, and explain their finite size scaling relations. For large systems at finite pressure, the critical strain vanishes but the ratio of shear modulus before and after a contact change approaches one: linear response remains relevant in large systems. For finite systems close to jamming the critical strain also vanishes, but here linear response already breaks down after a single contact change.

  4. Contact Changes near Jamming

    E-print Network

    Merlijn S. van Deen; Johannes Simon; Zorana Zeravcic; Simon Dagois-Bohy; Brian P. Tighe; Martin van Hecke

    2014-08-18

    We probe the onset and effect of contact changes in soft harmonic particle packings which are sheared quasistatically. We find that the first contact changes are the creation or breaking of contacts on a single particle. We characterize the critical strain, statistics of breaking versus making a contact, and ratio of shear modulus before and after such events, and explain their finite size scaling relations. For large systems at finite pressure, the critical strain vanishes but the ratio of shear modulus before and after a contact change approaches one: linear response remains relevant in large systems. For finite systems close to jamming the critical strain also vanishes, but here linear response already breaks down after a single contact change.

  5. Promoter activation by CII, a potent transcriptional activator from bacteriophage 186.

    PubMed

    Murchland, Iain; Ahlgren-Berg, Alexandra; Priest, David G; Dodd, Ian B; Shearwin, Keith E

    2014-11-14

    The lysogeny promoting protein CII from bacteriophage 186 is a potent transcriptional activator, capable of mediating at least a 400-fold increase in transcription over basal activity. Despite being functionally similar to its counterpart in phage ?, it shows no homology at the level of protein sequence and does not belong to any known family of transcriptional activators. It also has the unusual property of binding DNA half-sites that are separated by 20 base pairs, center to center. Here we investigate the structural and functional properties of CII using a combination of genetics, in vitro assays, and mutational analysis. We find that 186 CII possesses two functional domains, with an independent activation epitope in each. 186 CII owes its potent activity to activation mechanisms that are dependent on both the ?(70) and ? C-terminal domain (?CTD) components of RNA polymerase, contacting different functional domains. We also present evidence that like ? CII, 186 CII is proteolytically degraded in vivo, but unlike ? CII, 186 CII proteolysis results in a specific, transcriptionally inactive, degradation product with altered self-association properties. PMID:25294872

  6. Contact Manifolds, Contact Instantons, and Twistor Geometry

    E-print Network

    Martin Wolf

    2012-06-29

    Recently, Kallen and Zabzine computed the partition function of a twisted supersymmetric Yang-Mills theory on the five-dimensional sphere using localisation techniques. Key to their construction is a five-dimensional generalisation of the instanton equation to which they refer as the contact instanton equation. Subject of this article is the twistor construction of this equation when formulated on K-contact manifolds and the discussion of its integrability properties. We also present certain extensions to higher dimensions and supersymmetric generalisations.

  7. Optical contact micrometer

    DOEpatents

    Jacobson, Steven D.

    2014-08-19

    Certain examples provide optical contact micrometers and methods of use. An example optical contact micrometer includes a pair of opposable lenses to receive an object and immobilize the object in a position. The example optical contact micrometer includes a pair of opposable mirrors positioned with respect to the pair of lenses to facilitate viewing of the object through the lenses. The example optical contact micrometer includes a microscope to facilitate viewing of the object through the lenses via the mirrors; and an interferometer to obtain one or more measurements of the object.

  8. Clevudine: a potent inhibitor of hepatitis B virus in vitro and in vivo.

    PubMed

    Korba, Brent E; Furman, Phillip A; Otto, Michael J

    2006-08-01

    Clevudine (CLV) is a nucleoside analog of the unnatural L-configuration that has potent anti-hepatitis B virus (HBV) activity in vitro and in vivo with a favorable toxicity profile in all species tested. In cell culture, CLV is readily phosphorylated to the corresponding 5'-triphosphate form of the compound. The mechanism of action of CLV involves the inhibition of the HBV polymerase by CLV 5'-triphosphate. In vivo efficacy studies performed in the duck and woodchuck models showed marked, rapid inhibition of virus replication and no significant toxicity. In the woodchuck model, there was a dose-dependent delay in viral recrudescence and a reduction or loss of covalently closed circular DNA. In Phase II clinical studies, CLV was well tolerated and exhibited potent antiviral activity at all doses investigated. In Phase III studies in both hepatitis B e antigen (HBeAg)-positive and -negative patients, CLV 30 mg administered once daily demonstrated potent antiviral efficacy and significant biochemical improvement after only 24 weeks of therapy. These effects were sustained in a significant portion of the patients when therapy was stopped after 6 months with no viral rebound occurring in approximately 3 and 16% in HBeAg-positive and -negative patients, respectively. There have been no significant safety or tolerance issues associated with the drug in these studies. Future studies will investigate the safety and tolerance of CLV 30 mg given once daily over 48 weeks and longer. PMID:17009935

  9. Discovery of 3,3'-diindolylmethanes as potent antileishmanial agents.

    PubMed

    Bharate, Sandip B; Bharate, Jaideep B; Khan, Shabana I; Tekwani, Babu L; Jacob, Melissa R; Mudududdla, Ramesh; Yadav, Rammohan R; Singh, Baljinder; Sharma, P R; Maity, Sudip; Singh, Baldev; Khan, Ikhlas A; Vishwakarma, Ram A

    2013-05-01

    An efficient protocol for synthesis of 3,3'-diindolylmethanes using recyclable Fe-pillared interlayered clay (Fe-PILC) catalyst under aqueous medium has been developed. All synthesized 3,3'-diindolylmethanes showed promising antileishmanial activity against Leishmania donovani promastigotes as well as axenic amastigotes. Structure-activity relationship analysis revealed that nitroaryl substituted diindolylmethanes showed potent antileishmanial activity. The 4-nitrophenyl linked 3,3'-diindolylmethane 8g was found to be the most potent antileishmanial analog showing IC50 values of 7.88 and 8.37 ?M against both L. donovani promastigotes and amastigotes, respectively. Further, a pharmacophore based QSAR model was established to understand the crucial molecular features of 3,3'-diindolylmethanes essential for potent antileishmanial activity. These compounds also exhibited promising antifungal activity against Cryptococcus neoformans, wherein fluorophenyl substituted 3,3'-diindolylmethanes were found to be most potent antifungal agents. Developed synthetic protocol will be useful for economical and eco-friendly synthesis of potent antileishmanial and antifungal 3,3'-diindolylmethane class of compounds. PMID:23517732

  10. Discovery of 3,3?-diindolylmethanes as potent antileishmanial agents

    PubMed Central

    Bharate, Sandip B.; Bharate, Jaideep B.; Khan, Shabana I.; Tekwani, Babu L.; Jacob, Melissa R.; Mudududdla, Ramesh; Yadav, Rammohan R.; Singh, Baljinder; Sharma, P. R.; Maity, Sudip; Singh, Baldev; Khan, Ikhlas A.; Vishwakarma, Ram A.

    2013-01-01

    An efficient protocol for synthesis of 3,3?-diindolyl methanes using recyclable Fe – pillared interlayered clay (Fe-PILC) catalyst under aqueous medium have been developed. All synthesized 3,3?-diindolylmethanes showed promising antileishmanial activity against Leishmania donovani promastigotes as well as axenic amastigotes. Structure-activity relationship analysis revealed that nitroaryl substituted diindolylmethanes showed potent antileishmanial activity. The 4-nitrophenyl linked 3,3?-diindolylmethane 8g was found to be the most potent antileishmanial analog showing IC50 values of 7.88 and 8.37 ?M against both L. donovani promastigotes and amastigotes, respectively. Further, a pharmacophore based QSAR model was established to understand the crucial molecular features of 3,3?-diindolylmethanes essential for potent antileishmanial activity. These compounds also exhibited promising antifungal activity against Cryptococcus neoformans, wherein fluorophenyl substituted 3,3?-diindolylmethanes were found to be most potent antifungal agents. Developed synthetic protocol will be useful for economical and eco-friendly synthesis of potent antileishmanial and antifungal 3,3?-diindolylmethane class of compounds. PMID:23517732

  11. Hertzian contact Lamb wave sensors

    NASA Astrophysics Data System (ADS)

    Degertekin, Fahrettin Levent

    1997-08-01

    This dissertation describes the development of ultrasonic Hertzian contact Lamb wave transducer and its applications in semiconductor process monitoring and non- destructive testing. The Hertzian contact transducer excites the lowest order Lamb wave modes selectively with high signal to noise ratio. It couples energy to the sample plates through a dry, solid-to-solid contact enabling novel ultrasonic applications. Lamb wave propagation in layered anisotropic plates is investigated using the surface impedance method. Internal field and energy distributions are discussed to form a basis for the Lamb wave excitation problem. Combining these results with the angular spectrum method and normal mode theory, a general 2 dimensional model for Lamb wave excitation by mode conversion is developed. The model is used to evaluate the mode selectivity and efficiency of Lamb wave transducers operating on multilayered plates with general anisotropy. The normal mode theory is also used to analyze Lamb wave excitation by surface contact sources. Several Hertzian contact transducers are implemented using this analysis and it is shown that these transducers can be used to selectively excite the lowest order Lamb waves. An ultrasonic temperature sensor (UTS) using Hertzian contact transducers is implemented and used for accurate, in-situ temperature measurement in various semiconductor processing environments. The UTS is sensitive to temperature in a wide range and it is not affected by the optical and electronic properties of the semiconductor wafers. Applications of the UTS in a rapid thermal processor, and in particular its use in a unique method for monitoring both crystallization and temperature during the manufacture of thin film transistors are discussed. A real-time wafer temperature tomography system based on the UTS is also described. When used as point-like source and receiver pairs, Hertzian contact Lamb wave transducers provide accurate phase velocity measurements. For characterization of anisotropic plates, a wavefront correction method is derived and the results are compared with measurements on single crystal and composite plates. It is shown that it is possible to use the same technique for delamination detection in composite plates.

  12. Contact dependent growth inhibition of E. coli O157:H7 by EC869 CDI system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Contact Dependent Growth Inhibition (CDI) is a recently discovered mechanism that microorganisms use to compete in various microecosystems. CDI systems express large cell surface exposed CdiA proteins with potent antimicrobial peptide tips. Many CDI systems also contain additional down...

  13. Benzofuran-derived benzylpyridinium bromides as potent acetylcholinesterase inhibitors.

    PubMed

    Baharloo, Farzaneh; Moslemin, Mohammad Hossein; Nadri, Hamid; Asadipour, Ali; Mahdavi, Mohammad; Emami, Saeed; Firoozpour, Loghman; Mohebat, Razieh; Shafiee, Abbas; Foroumadi, Alireza

    2015-03-26

    A series of benzofuran-based N-benzylpyridinium derivatives 5a-o were designed and synthesized as novel AChE inhibitors. The synthetic pathway of the compounds involved the preparation of 4-(benzofuran-2-yl)pyridine intermediates via the reaction of different salicylaldehyde derivatives and 4-(bromomethyl)pyridine, followed by intramolecular cyclization. Subsequently, the 4-(benzofuran-2-yl)pyridines were N-benzylated by using appropriate benzyl bromide to afford the final product 5a-o. The results of in vitro AChE activity evaluation of synthesized compounds revealed that all compound had potent anti-AChE activity comparable or more potent than standard drug donepezil. The N-(3,5-dimethylbenzyl) derivative 5e with IC50 value of 4.1 nM was the most active compound, being 7-fold more potent than donepezil. PMID:25681712

  14. Please complete "Contact Information" AND 1) have a Licensed Health Care Provider complete the rest of the form OR 2) submit required immunization records. Send to: Student Health Services, Immunization Compliance, 374 East Grand

    E-print Network

    Nickrent, Daniel L.

    of the form OR 2) submit required immunization records. Send to: Student Health Services, Immunization forms to immunizations@siu.edu. Questions? Please call (618) 453-4326. VERIFICATION REQUIRED BY LICENSED RECOMMENDED IMMUNIZATIONS MENINGITIS* 1 2 Menactra Menveo Meningococcal (unspecified) HEPATITIS B 1 2 3

  15. Enhancing Intergenerational Contact.

    ERIC Educational Resources Information Center

    Ralston, Penny A.; And Others

    This document is a curriculum module designed to assist secondary school home economic teachers in teaching students about aging. The three major purposes of this module are to provide data-based information on aging related to needs of students to enhance intergenerational contact; to facilitate the expansion of intergenerational contacts by…

  16. Contacts & Information Sources

    Cancer.gov

    PLCO participants who wish to update their information may contact: PLCO CDCC Manager: Samantha Lewis Email: samanthalewis@westat.com Phone: (888) 886-0750 Fax: (888) 251-1690 Contacts and Information Sources PLCO Project Officer Kelly Yu, PhD Early Detection

  17. NCI Staff Contacts

    Cancer.gov

    Updated: May 28, 2013 Updated: May 28, 2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K05 Award, contact: Dr. Susan N. PerkinsProgram DirectorE-mail: perkinsu@mail.nih.gov Branch

  18. Identifying the causes of contact dermatitis.

    PubMed

    Jones, Ruth; Horn, Helen M

    2014-06-01

    Contact dermatitis results from skin contact with an exogenous substance. It can be caused by direct contact, airborne particles, vapours or light. Individuals of any age can be affected. The two most common variants are irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD). ICD is more common and has a worse prognosis. Other less common forms of contact dermatitis include photocontact allergy and, in food handlers, protein contact dermatitis. ICD is a form of eczema and is induced by direct inflammatory pathways without prior sensitisation. Classical ACD is mediated by type 4 cell-mediated immunity. Sensitisation occurs within 5 to 16 days of skin contact with a potential allergen but at this first exposure there is no inflammation. Frequent exposure and high concentrations of potential allergens increase the risk of sensitisation. If eczema is recurrent/persistent, or occurs in an individual with no previous history of eczema, contact dermatitis should be considered. Dorsal aspects of the hands are most often affected by ICD, usually with involvement of the finger webs. Cumulative effects of water, soaps and detergents are the most common cause of ICD which affects the hands more often than any other site. Nickel, fragrances, rubber accelerators and biocides are the most common sensitisers in ACD. Patients with leg ulcers and stasis eczema are at especially high risk of developing allergies to ingredients of their topical treatments, dressings and bandages. If ACD is suspected the patient should be referred to secondary care for patch testing. Age should not be a deterrent to patch testing. Accurate diagnosis, avoidance of identified allergens and protection from irritants are the key to successful treatment. PMID:25102574

  19. Induction of contact-dependent CD8+ regulatory T cells through stimulation with staphylococcal and streptococcal superantigens*

    PubMed Central

    Taylor, Amanda L; Cross, Elizabeth L A; Llewelyn, Martin J

    2012-01-01

    The bacterial superantigen exotoxins of Staphylococcus aureus and Streptococcus pyogenes are potent stimulators of polyclonal T-cell proliferation. They are the causes of toxic shock syndrome but also induce CD25+ FOXP3+ regulatory cells in the CD4 compartment. Several studies have recently described different forms of antigen-induced regulatory CD8+ T cells in the context of inflammatory diseases and chronic viral infections. In this paper we show that bacterial superantigens are potent inducers of human regulatory CD8+ T cells. We used four prototypic superantigens of S. aureus (toxic shock syndrome toxin-1 and staphylococcal enterotoxin A) and Str. pyogenes (streptococcal pyrogenic exotoxins A and K/L). At concentrations below 1 ng/ml each toxin triggers concentration-dependent T-cell receptor V?-specific expression of CD25 and FOXP3 on CD8+ T cells. This effect is independent of CD4+ T-cell help but requires antigen-presenting cells for maximum effect. The cells also express the activation/regulatory markers cytotoxic T-lymphocyte antigen-4 and glucocorticoid-induced tumour necrosis factor receptor-related protein and skin homing adhesins CD103 and cutaneous lymphocyte-associated antigen. Superantigen-induced CD25+ FOXP3+ CD8+ T cells were as potent as freshly prepared naturally occurring CD4+ regulatory T cells in suppressing proliferation of CD4+ CD25? T cells in response to anti-CD3 stimulation. Although superantigen-induced CD8+ CD25+ FOXP3+ express interleukin-10 and interferon-? their suppressive function is cell contact dependent. Our findings indicate that regulatory CD8+ T cells may be a feature of acute bacterial infections contributing to immune evasion by the microbe and disease pathogenesis. The presence and magnitude of regulatory CD8+ T-cell responses may represent a novel biomarker in such infections. Superantigen-induced regulatory CD8+ T cells also have therapeutic potential. PMID:22043981

  20. TIGER FUND REQUEST FORM Organization Name

    E-print Network

    Bogaerts, Steven

    TIGER FUND REQUEST FORM Organization Name: President Name/contact: Treasurer Name/contact: Total Amount Organization is requesting: Tiger Fund hearing date your organization is attending: (Form must at time of request. #12;TIGER FUND GUIDELINES, PROCEDURES, AND REQUEST FORM I. Introduction The Tiger

  1. A unified model for insulator selection to form ultra-low resistivity metal-insulator-semiconductor contacts to n-Si, n-Ge, and n-InGaAs

    E-print Network

    Yener, Aylin

    A unified model for insulator selection to form ultra-low resistivity metal- insulator. Lett. 101, 032101 (2012) Determination of graphene work function and graphene-insulator. Phys. Lett. 101, 023504 (2012) Towards spin injection from silicon into topological insulators

  2. Amorphous Ge bipolar blocking contacts on Ge detectors

    SciTech Connect

    Luke, P.N.; Cork, C.P.; Madden, N.W.; Rossington, C.S.; Wesela, M.F. (Lawrence Berkeley Lab., CA (United States))

    1992-08-01

    This paper reports on electrical contacts formed using sputtered amorphous Ge (a-Ge) films on high-purity Ge crystals, both n- and p-type, were found to exhibit good blocking behavior with low leakage currents, with the contact biased under either voltage polarity. The a-Ge contacts have thin dead layers associated with them and can be used in place of lithium-diffused, ion-implanted or Schottky barrier contacts on Ge radiation detectors. The use of such contacts allows fabrication of multielectrode detectors by means of simple processing steps.

  3. Allergic contact dermatitis.

    PubMed

    Becker, Detlef

    2013-07-01

    Allergic contact dermatitis is a frequent inflammatory skin disease. The suspected diagnosis is based on clinical symptoms, a plausible contact to allergens and a suitable history of dermatitis. Differential diagnoses should be considered only after careful exclusion of any causal contact sensitization. Hence, careful diagnosis by patch testing is of great importance. Modifications of the standardized test procedure are the strip patch test and the repeated open application test. The interpretation of the SLS (sodium lauryl sulfate) patch test as well as testing with the patients' own products and working materials are potential sources of error. Accurate patch test reading is affected in particular by the experience and individual factors of the examiner. Therefore, a high degree of standardization and continuous quality control is necessary and may be supported by use of an online patch test reading course made available by the German Contact Dermatitis Research Group. A critical relevance assessment of allergic patch test reactions helps to avoid relapses and the consideration of differential diagnoses. Any allergic test reaction should be documented in an allergy ID card including the INCI name, if appropriate. The diagnostics of allergic contact dermatitis is endangered by a seriously reduced financing of patch testing by the German statutory health insurances. Restrictive regulations by the German Drug Law block the approval of new contact allergens for routine patch testing. Beside the consistent avoidance of allergen contact, temporary use of systemic and topical corticosteroids is the therapy of first choice. PMID:23802782

  4. CONTACT HANDLE DECOMPOSITIONS BURAK OZBAGCI

    E-print Network

    Ozbagci, Burak

    CONTACT HANDLE DECOMPOSITIONS BURAK OZBAGCI ABSTRACT. We review Giroux's contact handles and contact handle attachments in dimen- sion three and show that a bypass attachment consists of a pair of contact 1 and 2-handles. As an application we describe explicit contact handle decompositions

  5. Low resistance, nonalloyed Ohmic contacts to InGaAs Adam M. Crook,a

    E-print Network

    Rodwell, Mark J. W.

    Low resistance, nonalloyed Ohmic contacts to InGaAs Adam M. Crook,a Erik Lind, Zach Griffith November 2007 We report extremely low specific contact resistivity c nonalloyed Ohmic contacts to n-type In0.53Ga0.47As, lattice matched to InP. Contacts were formed by oxidizing the semiconductor surface

  6. Ultralow resistance, nonalloyed Ohmic contacts to n-InGaAs Ashish K. Baraskara

    E-print Network

    Rodwell, Mark J. W.

    Ultralow resistance, nonalloyed Ohmic contacts to n-InGaAs Ashish K. Baraskara ECE, University 2009 The authors report ultralow specific contact resistivity c in nonalloyed, in situ Ohmic contacts matched to InP. The contacts were formed by depositing molybdenum Mo immediately after the In0.53Ga0.47As

  7. Can Imagined Interactions Produce Positive Perceptions?: Reducing Prejudice through Simulated Social Contact

    ERIC Educational Resources Information Center

    Crisp, Richard J.; Turner, Rhiannon N.

    2009-01-01

    The contact hypothesis states that, under the right conditions, contact between members of different groups leads to more positive intergroup relations. The authors track recent trends in contact theory to the emergence of extended, or indirect, forms of contact. These advances lead to an intriguing proposition: that simply imagining intergroup…

  8. Telescopic vision contact lens

    NASA Astrophysics Data System (ADS)

    Tremblay, Eric J.; Beer, R. Dirk; Arianpour, Ashkan; Ford, Joseph E.

    2011-03-01

    We present the concept, optical design, and first proof of principle experimental results for a telescopic contact lens intended to become a visual aid for age-related macular degeneration (AMD), providing magnification to the user without surgery or external head-mounted optics. Our contact lens optical system can provide a combination of telescopic and non-magnified vision through two independent optical paths through the contact lens. The magnified optical path incorporates a telescopic arrangement of positive and negative annular concentric reflectors to achieve 2.8x - 3x magnification on the eye, while light passing through a central clear aperture provides unmagnified vision.

  9. Optical contacting of quartz

    NASA Technical Reports Server (NTRS)

    Payne, L. L.

    1982-01-01

    The strength of the bond between optically contacted quartz surfaces was investigated. The Gravity Probe-B (GP-B) experiment to test the theories of general relativity requires extremely precise measurements. The quartz components of the instruments to make these measurements must be held together in a very stable unit. Optical contacting is suggested as a possible method of joining these components. The fundamental forces involved in optical contacting are reviewed and relates calculations of these forces to the results obtained in experiments.

  10. Two tarantula venom peptides as potent and differential Na(V) channels blockers.

    PubMed

    Cherki, Ronit S; Kolb, Ela; Langut, Yael; Tsveyer, Lior; Bajayo, Nissim; Meir, Alon

    2014-01-01

    Voltage dependent sodium (Na(V)) channels are large membrane spanning proteins which lie in the basis of action potential generation and propagation in excitable cells and hence are essential mediators of neuronal signaling. Inhibition of Na(V) channel activity is one of the core mechanisms to treat conditions related to neuronal hyperexcitability, such as epilepsy in the clinic. Na(V) channel blockers are also extensively used to locally inhibit action potential generation and related pain perceptions in the form of local anesthetics. Here we describe the isolation, biochemical characterization, synthesis and in vitro characterization of two potent Na(V) channel blockers from the venom of the Paraphysa scrofa (Phrixotrichus auratus) tarantula spider. Both Voltage sensor toxin 3 (VSTx-3, ?-theraphotoxin-Gr4a) and GTx1-15 (Toxin Gtx1-15), were originally isolated from the venom of the related tarantula Grammostola rosea and described as K(V) and Ca(V) channel blockers, respectively. In our hands, GTx1-15 was shown to be a potent inhibitor of tetrodotoxin (TTX)-sensitive channels (IC?? 0.007 ?M for hNa(V)1.7 and 0.12 ?M for hNa(V)1.3 channels), with very little effect on TTX-resistant (Na(V)1.5 and NaV1.8) channels. VSTx-3 was demonstrated to be a potent, TTX-sensitive sodium channel blocker and especially, potent blocker of Na(V)1.8 channels (IC?? 0.19 ?M for hNa(V)1.3, 0.43 ?M for hNa(V)1.7 and 0.77 ?M for hNa(V)1.8 channels). Such potent inhibitors with differential selectivity among Na(V) channel isoforms may be used as tools to study the roles of the different channels in processes related to hyperexcitability and as lead compounds to treat pathological pain conditions. PMID:24211312

  11. Diastereomeric Spirooxindoles as Highly Potent and Efficacious MDM2 Inhibitors

    PubMed Central

    Zhao, Yujun; Liu, Liu; Sun, Wei; Lu, Jianfeng; McEachern, Donna; Xiaoqin, Li; Yu, Shanghai; Bernard, Denzil; Ochsenbein, Philippe; Ferey, Vincent; Carry, Jean-Christophe; Deschamps, Jeffrey R.; Sun, Duxin; Wang, Shaomeng

    2013-01-01

    Small-molecule inhibitors that block the MDM2-p53 protein-protein interaction (MDM2 inhibitors) are being intensely pursued as a new therapeutic strategy for cancer treatment. We previously published a series of spirooxindole-containing compounds as a new class of MDM2 small-molecule inhibitors. We report herein a reversible ring opening-cyclization reaction for some of these spirooxindoles, which affords four diastereomers from a single compound. Our biochemical binding data showed that the stereo-chemistry in this class of compounds has a major effect on their binding affinities to MDM2; with >100-fold difference between the most potent and the least potent stereoisomers. Our study has led to the identification of a set of highly potent MDM2 inhibitors with a stereochemistry that is different from that of our previously reported compounds. The most potent compound (MI-888) binds to MDM2 with a Ki value of 0.44 nM and achieves complete and long-lasting tumor regression in an animal model of human cancer. PMID:23641733

  12. Tin: A Potent Inducer of Heme Oxygenase in Kidney

    Microsoft Academic Search

    Attallah Kappas; Mahin D. Maines

    1976-01-01

    Tin greatly enhances heme breakdown in kidney, thus impairing heme-dependent cellular functions, such as cytochrome P-450 mediated drug biotransformation. This novel action of the metal results from a potent induction effect on heme oxygenase, the enzyme that catalyzes heme oxidation in microsomes. The possible toxicological implications of this tin effect in the kidney merit further investigation.

  13. A new series of potent benzodiazepine ?-secretase inhibitors

    Microsoft Academic Search

    Ian Churcher; Kate Ashton; John W. Butcher; Earl E. Clarke; Timothy Harrison; Huw D. Lewis; Andrew P. Owens; Martin R. Teall; Susie Williams; Jonathan D. J. Wrigley

    2003-01-01

    A new series of benzodiazepine-containing ?-secretase inhibitors with potential use in the treatment of Alzheimer's disease is disclosed. Structure–activity relationships of the pendant hydrocinnamate side-chain which led to the preparation of highly potent inhibitors are described.

  14. Isolation of peptides of the brevinin-1 family with potent

    E-print Network

    Davidson, Carlos

    member of the temporin family were also isolated from the secretions but showed relatively low potencyIsolation of peptides of the brevinin-1 family with potent candidacidal activity from the skin secretions of the frog Rana boylii J. M. Conlon A´. Sonnevend M. Patel C. Davidson P. F. Nielsen T. Pa´l L. A

  15. RESEARCH Open Access Potent bace-1 inhibitor design using

    E-print Network

    Lee, Keun Woo

    RESEARCH Open Access Potent bace-1 inhibitor design using pharmacophore modeling, in silico formation that lead to memory and cognitive defects in Alzheimer's disease (AD). AD is a ravaging Research Center (EB-NCRC), Gyeongsang National University (GNU), 900 Gazwa-dong, Jinju 660-701. Republic

  16. Potent pyrrolidine- and piperidine-based BACE-1 inhibitors

    SciTech Connect

    Iserloh, U.; Wu, Y.; Cumming, J.N.; Pan, J.; Wang, L.Y.; Stamford, A.W.; Kennedy, M.E.; Kuvelkar, R.; Chen, X.; Parker, E.M.; Strickland, C.; Voigt, J. (Schering-Plough)

    2008-08-18

    Based on lead compound 1 identified from the patent literature, we developed novel patentable BACE-1 inhibitors by introducing a cyclic amine scaffold. Extensive SAR studies on both pyrrolidines and piperidines ultimately led to inhibitor 2f, one of the most potent inhibitors synthesized to date. The discovery and development of novel BACE-1 inhibitors incorporating a cyclic amine scaffold is described.

  17. Potent Antioxidant Dendrimers Lacking Pro-oxidant Activity

    PubMed Central

    Lee, Choon Young; Sharma, Ajit; Uzarski, Rebecca L.; Cheong, Jae Eun; Xu, Hao; Held, Rich A.; Upadhaya, Samik K.; Nelson, Julie L.

    2010-01-01

    It is well known that antioxidants have protective effects against oxidative stress. Unfortunately, in the presence of transition metals, antioxidants including polyphenols with potent antioxidant activities may also exhibit pro-oxidant effects, which may irreversibly damage DNA. Therefore, antioxidants with strong free radical scavenging abilities and devoid of pro-oxidant effects would be of immense biological importance. We report two antioxidant dendrimers with a surface rich in multiple phenolic hydroxyl groups, benzylic hydrogens and electron donating ring substituents that contribute to their potent free radical quenching property. In order to minimize their pro-oxidant effects, the dendrimers were designed with a metal chelating tris(2-aminoethyl)amine (TREN) core. The dendritic antioxidants were prepared by attachment of six syringaldehyde or vanillin molecules to TREN by reductive amination. They exhibited potent radical scavenging properties: 5 times stronger than quercetin and 15 times more potent than Trolox according to the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The antioxidant dendrimers also protected low-density lipoprotein, lysozyme and DNA against 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced free radical damage. More importantly, unlike quercetin and Trolox, the two TREN antioxidant dendrimers did not damage DNA via their pro-oxidant effects when incubated with physiological amounts of copper ions. The dendrimers also showed no cytotoxicity towards Chinese hamster ovary cells. PMID:20977937

  18. Extensive screening for herbal extracts with potent antioxidant properties

    PubMed Central

    Niwano, Yoshimi; Saito, Keita; Yoshizaki, Fumihiko; Kohno, Masahiro; Ozawa, Toshihiko

    2011-01-01

    This paper summarizes our research for herbal extracts with potent antioxidant activity obtained from a large scale screening based on superoxide radical (O2•?) scavenging activity followed by characterization of antioxidant properties. Firstly, scavenging activity against O2•? was extensively screened from ethanol extracts of approximately 1000 kinds of herbs by applying an electron spin resonance (ESR)-spin trapping method, and we chose four edible herbal extracts with prominently potent ability to scavenge O2•?. They are the extracts from Punica granatum (Peel), Syzygium aromaticum (Bud), Mangifera indica (Kernel), and Phyllanthus emblica (Fruit). These extracts were further examined to determine if they also scavenge hydroxyl radical (•OH), by applying the ESR spin-trapping method, and if they have heat resistance as a desirable characteristic feature. Experiments with the Fenton reaction and photolysis of H2O2 induced by UV irradiation demonstrated that all four extracts have potent ability to directly scavenge •OH. Furthermore, the scavenging activities against O2•? and •OH of the extracts of P. granatum (peel), M. indica (kernel) and P. emblica (fruit) proved to be heat-resistant. The results of the review might give useful information when choosing a potent antioxidant as a foodstuff. For instance, the four herbal extracts chosen from extensive screening possess desirable antioxidant properties. In particular, the extracts of the aforementioned three herbs are expected to be suitable for food processing in which thermal devices are used, because of their heat resistance. PMID:21297917

  19. Discovery of DF-461, a Potent Squalene Synthase Inhibitor

    PubMed Central

    2013-01-01

    We report the development of a new trifluoromethyltriazolobenzoxazepine series of squalene synthase inhibitors. Structure–activity studies and pharmacokinetics optimization on this series led to the identification of compound 23 (DF-461), which exhibited potent squalene synthase inhibitory activity, high hepatic selectivity, excellent rat hepatic cholesterol synthesis inhibitory activity, and plasma lipid lowering efficacy in nonrodent repeated dose studies. PMID:24900587

  20. Carrageenan Is a Potent Inhibitor of Papillomavirus Infection

    Microsoft Academic Search

    Christopher B. Buck; Cynthia D. Thompson; Jeffrey N. Roberts; Martin Müller; Douglas R. Lowy; John T. Schiller

    2006-01-01

    Certain sexually transmitted human papillomavirus (HPV) types are causally associated with the development of cervical cancer. Our recent development of high-titer HPV pseudoviruses has made it possible to perform high-throughput in vitro screens to identify HPV infection inhibitors. Comparison of a variety of compounds revealed that carrageenan, a type of sulfated polysaccharide extracted from red algae, is an extremely potent

  1. The contact caveat: negative contact predicts increased prejudice more than positive contact predicts reduced prejudice.

    PubMed

    Barlow, Fiona Kate; Paolini, Stefania; Pedersen, Anne; Hornsey, Matthew J; Radke, Helena R M; Harwood, Jake; Rubin, Mark; Sibley, Chris G

    2012-12-01

    Contact researchers have largely overlooked the potential for negative intergroup contact to increase prejudice. In Study 1, we tested the interaction between contact quantity and valence on prejudice toward Black Australians (n = 1,476), Muslim Australians (n = 173), and asylum seekers (n = 293). In all cases, the association between contact quantity and prejudice was moderated by its valence, with negative contact emerging as a stronger and more consistent predictor than positive contact. In Study 2, White Americans (n = 441) indicated how much positive and negative contact they had with Black Americans on separate measures. Although both quantity of positive and negative contact predicted racism and avoidance, negative contact was the stronger predictor. Furthermore, negative (but not positive) contact independently predicted suspicion about Barack Obama's birthplace. These results extend the contact hypothesis by issuing an important caveat: Negative contact may be more strongly associated with increased racism and discrimination than positive contact is with its reduction. PMID:22941796

  2. Contact electrification and energy harvesting using periodically contacted and squeezed water droplets.

    PubMed

    Helseth, L E; Guo, X D

    2015-03-17

    We investigate the contact electrification occurring when a small water droplet resting on a metal electrode is brought periodically in contact with a hydrophobic film of fluorinated ethylene propylene. It is found that the maximum current increases with the drop volume according to a power law. The time scale for the contact current to develop is consistent with that required for a droplet to spread and is, therefore, longer than the time required to form the electric double layer. Adding salt into the water does reduce the contact current but not entirely, which suggests that any remaining water layer cannot entirely neutralize the charges developed upon contact. With an average power of 0.7 ?W and a peak power near 5 ?W at a frequency of 5 Hz, a 200 ?L droplet of pure water can be used to light up a light-emitting diode. PMID:25730607

  3. Effect of Contact Force Between Rough Surfaces on Real Contact Area and Electrical Contact Resistance

    E-print Network

    Paris-Sud XI, Université de

    Effect of Contact Force Between Rough Surfaces on Real Contact Area and Electrical Contact and the real contact area between rough surfaces as a function of the contact force. This application, surface roughness effects were ignored in the analysis, due to the difficulty to generate a rough surface

  4. Wetting and Contact Angle

    NSDL National Science Digital Library

    NSF CAREER Award and RET Program, Mechanical Engineering and Material Science,

    Students are presented with the concepts of wetting and contact angle. They are also introduced to the distinction between hydrophobic and hydrophilic surfaces. Students observe how different surfaces are used to maintain visibility under different conditions.

  5. Contact thermal lithography

    E-print Network

    Schmidt, Aaron Jerome, 1979-

    2004-01-01

    Contact thermal lithography is a method for fabricating microscale patterns using heat transfer. In contrast to photolithography, where the minimum achievable feature size is proportional to the wavelength of light used ...

  6. Contact Lenses and Cosmetics

    MedlinePLUS

    ... Z Listing Good Vision For Life Infants Children Adults Seniors Caring for Your Vision Eye & Vision Exams Contact Lenses Diet and Nutrition UV Protection Resources for Teachers 3D Vision & Eye Health Classroom Exercises ...

  7. Ohmic Contacts on Semiconductors

    NSDL National Science Digital Library

    This video from the Indian Institute of Technology, hosted by YouTube, contains a lecture which demonstrates ohmic contacts on semiconductors. The lecture includes slides with equations illustrating related concepts. Running time: 57:48.

  8. Contact Information-OCCAM

    Cancer.gov

    Contact Us | Sitemap CAM at the NCI NCI CAM History Highlights of NCI CAM Activities NCI CAM Annual Report Research Funding Opportunities Grant Application Information Research Resources Funded Research Research Results Training Opportunities FAQ's

  9. About CTEP — Contact Information

    Cancer.gov

    Skip to Content Home | Investigator Resources | Protocol Development | Initiatives/Programs/Collaborations | Links to More Resources | Funding Opportunities | About CTEP Home | Sitemap | Contact CTEP Search this site About CTEP Mission Personnel Organization

  10. CTEP — Forms, Templates and Documents

    Cancer.gov

    Skip to Content Home | Investigator Resources | Protocol Development | Initiatives/Programs/Collaborations | Links to More Resources | Funding Opportunities | About CTEP Home | Sitemap | Contact CTEP Search this site Forms, Templates and Documents CTEP

  11. A silver nanocomposite biomaterial for blood-contacting implants.

    PubMed

    de Mel, Achala; Chaloupka, Karla; Malam, Yogeshkumar; Darbyshire, Arnold; Cousins, Brian; Seifalian, Alexander M

    2012-09-01

    Cardiovascular implants must resist infection and thrombosis. A nanocomposite polymeric material [polyhedral-oligomeric-silsesquioxane-poly(carbonate-urea)urethane; POSS-PCU] demonstrates ideal properties for cardiovascular applications. Silver nanoparticles or nanosilver (NS) are recognized for efficient antibacterial properties. This study aims to determine the influence of NS integrated POSS-PCU on thrombogenicity. Silver nitrate was reduced with dimethylformamide and stabilized by the inclusion of fumed silica nanoparticles to prevent aggregation of NS and were incorporated into POSS-PCU to form a range of POSS-PCU-NS concentrations (by weight); 0.20% (NS16), 0.40% (NS32), 0.75% (NS64), and 1.50% (NS128). Surface wettability was determined with sessile-drop water contact angles. Platelets were introduced onto test samples and Alamar Blue (AB), mitochondrial-activity assay, quantified the degree of platelet adhesion whilst platelet-factor-4 (PF4) ELISA quantified the degree of platelet activation. Thromboelastography (TEG) determined the profiles of whole blood kinetics while hemolysis assay demonstrated the degree of blood compatibility. Increasing levels of NS induced greater hydrophilicity. A concentration dependant decrease in platelet adhesion and activation was observed with AB and PF4 readings, respectively. TEG demonstrated that the antithrombogenic properties of POSS-PCU were retained with POSS-PCU-NS16, and enhanced with POSS-PCU-NS32, but was reduced with POSS-PCU-NS64 and POSS-PCU-NS128. POSS-PCU-NS64 and POSS-PCU-NS128 demonstrated a hemolytic tendency, but no hemolysis was observed with POSS-PCU-NS16 and POSS-PCU-NS32. Overall, POSS-PCU-NS32 rendered potent antithrombogenic properties. PMID:22528182

  12. Allergic contact dermatitis: cosmetics

    Microsoft Academic Search

    Anton C. de Groot; Carolus-Liduina Ziekenhuis

    \\u000a Cosmetics are frequent causes of allergic contact dermatitis. After metals, ingredients of cosmetic products are the most\\u000a common contact allergens identified. Even in the general population, some 2-3% may be allergic to substances that are present\\u000a in cosmetics and toiletries [1]. The recent introduction of mandatory ingredient labelling in the European Union [2] has greatly facilitated diagnostic procedures in patients

  13. The impact of contact

    NASA Astrophysics Data System (ADS)

    Finney, B.

    1986-10-01

    Scenarios of the impact on human society of radio contact with an extraterrestrial civilization are presented. Some believe that contact with advanced extraterrestrials would quickly devastate the human spirit, while others believe that these super-intelligent beings would show the inhabitants of the earth how to live in peace. It is proposed that the possible existence of extraterrestrial civilizations and the development of means of studying and communicating with them need to be considered.

  14. Contact Allergy in Children

    Microsoft Academic Search

    Marie-Anne Morren; An Goossens

    \\u000a Contact allergy in children is more frequent than previously suspected. Certain contactants are characteristic of children\\u000a and may be responsible for unusual clinical presentations. Metals (jewelry, mobile phones), ingredients of pharmaceutical\\u000a and cosmetic products, para-phenylenediamine in tattoos, rubber additives (in shoes, toys, diapers, sports equipment, and\\u000a so on), plastics, resins (including those used in glues, orthopedic devices, electronic devices), and

  15. Time domain contact model for tyre/road interaction including nonlinear contact stiffness due to small-scale roughness

    NASA Astrophysics Data System (ADS)

    Andersson, P. B. U.; Kropp, W.

    2008-11-01

    Rolling resistance, traction, wear, excitation of vibrations, and noise generation are all attributes to consider in optimisation of the interaction between automotive tyres and wearing courses of roads. The key to understand and describe the interaction is to include a wide range of length scales in the description of the contact geometry. This means including scales on the order of micrometres that have been neglected in previous tyre/road interaction models. A time domain contact model for the tyre/road interaction that includes interfacial details is presented. The contact geometry is discretised into multiple elements forming pairs of matching points. The dynamic response of the tyre is calculated by convolving the contact forces with pre-calculated Green's functions. The smaller-length scales are included by using constitutive interfacial relations, i.e. by using nonlinear contact springs, for each pair of contact elements. The method is presented for normal (out-of-plane) contact and a method for assessing the stiffness of the nonlinear springs based on detailed geometry and elastic data of the tread is suggested. The governing equations of the nonlinear contact problem are solved with the Newton-Raphson iterative scheme. Relations between force, indentation, and contact stiffness are calculated for a single tread block in contact with a road surface. The calculated results have the same character as results from measurements found in literature. Comparison to traditional contact formulations shows that the effect of the small-scale roughness is large; the contact stiffness is only up to half of the stiffness that would result if contact is made over the whole element directly to the bulk of the tread. It is concluded that the suggested contact formulation is a suitable model to include more details of the contact interface. Further, the presented result for the tread block in contact with the road is a suitable input for a global tyre/road interaction model that is also based on the presented contact formulation.

  16. Exploring the Nature of Contact Freezing

    NASA Astrophysics Data System (ADS)

    Kiselev, A. A.; Hoffmann, N.; Duft, D.; Leisner, T.

    2012-12-01

    The freezing of supercooled water droplets upon contact with aerosol particles (contact nucleation of ice) is the least understood mechanism of ice formation in atmospheric clouds. Although experimental evidences suggest that some aerosols can be better IN in the contact than in the immersion mode (that is, triggering ice nucleation at higher temperature), no final explanation of this phenomena currently exists. On the other hand, the contact freezing is believed to be responsible for the enhanced rate of secondary ice formation occasionally observed in LIDAR measurements in the cold mixed phase clouds. Recently we have been able to show that the freezing of supercooled droplets electrodynamically levitated in the laminar flow containing mineral dust particles (kaolinite) is a process solely governed by a rate of collisions between the supercooled droplet and the aerosol particles. We have shown that the probability of droplet freezing on a single contact with aerosol particle may differ over an order of magnitude for kaolinite particles having different genesis and morphology. In this presentation we extend the study of contact nucleation of ice and compare the IN efficiency measured for DMA-selected kaolinite, illite and hematite particles. We show that the freezing probability increases towards unity as the temperature decreases and discuss the functional form of this temperature dependence. We explore the size dependence of the contact freezing probability and show that it scales with the surface area of the particles, thus resembling the immersion freezing behavior. However, for all minerals investigated so far, the contact freezing has been shown to dominate over immersion freezing on the short experimental time scales. Finally, based on the combined ESEM and electron microprobe analysis, we discuss the significance of particle morphology and variability of chemical composition on its IN efficiency in contact mode.

  17. This form should only be used by individuals who received a Ph.D. in the Biomedical Sciences. For medical school transcripts, please contact 718-430-2102 (phone), 718-430-4123 (fax)

    E-print Network

    Yates, Andrew

    -430-8655 or Mail to Einstein Graduate Programs in the Biomedical Sciences Albert Einstein College of Medicine 1300: Please complete form, then download and E-mail to sgregistrar@einstein.yu.edu or Fax to 718 OF ATTENDANCE: BANNER ID#: CELLPHONE NUMBER: LAB EXT. (If Current Student): PERMANENT E-MAIL (not Einstein e

  18. Contact induced deformation of enamel

    NASA Astrophysics Data System (ADS)

    He, Li Hong; Swain, Michael V.

    2007-04-01

    Teeth survive millions of contact cycles with relatively limited damage and wear, despite high local contact stresses. In this letter, the authors investigated the influence of enamel microstructure and specifically the role of the minor protein component on contact induced deformation. They assume that protein is responsible for the nonlinear contact stress-strain relationship. The extremely low contact stresses to induce inelastic contact deformation result in high contact induced energy loss which is indenter geometry dependent. A simple model shows that shear strain in protein layer is 16 times higher than the contact strain, and is where most deformation is dissipated.

  19. Activation of Hydrogen Peroxide to Peroxytetradecanoic Acid Is Responsible for Potent Inhibition of Protein Tyrosine Phosphatase CD45

    PubMed Central

    Kuban-Jankowska, Alicja; Winter, Philip; Gorska, Magdalena

    2012-01-01

    Hydrogen peroxide induces oxidation and consequently inactivation of many protein tyrosine phosphatases. It was found that hydrogen peroxide, in the presence of carboxylic acids, was efficiently activated to form even more potent oxidant - peroxy acid. We have found that peroxytetradecanoic acid decreases the enzymatic activity of CD45 phosphatase significantly more than hydrogen peroxide. Our molecular docking computational analysis suggests that peroxytetradecanoic acid has a higher binding affinity to the catalytic center of CD45 than hydrogen peroxide. PMID:23300686

  20. Three-phase contact line and line tension of electrolyte solutions in contact with charged substrates

    E-print Network

    Ingrid Ibagon; Markus Bier; S. Dietrich

    2015-04-10

    The three-phase contact line formed by the intersection of a liquid-vapor interface of an electrolyte solution with a charged planar substrate is studied in terms of classical density functional theory applied to a lattice model. The influence of the substrate charge density and of the ionic strength of the solution on the intrinsic structure of the three-phase contact line and on the corresponding line tension is analyzed. We find a negative line tension for all values of the surface charge density and of the ionic strength considered. The line tension increases upon decreasing the contact angle via varying either the temperature or the substrate charge density.

  1. Joint Contact Stress

    PubMed Central

    Brand, Richard A

    2005-01-01

    A joint's normal mechanical history contributes to the maintenance of articular cartilage and underlying bone. Loading facilitates the flow of nutrients into cartilage and waste products away, and additionally provides the mechanical signals essential for normal cell and tissue maintenance. Deleteriously low or high contact stresses have been presumed to result in joint deterioration, and particular aspects of the mechanical environment may facilitate repair of damaged cartilage. For decades, investigators have explored static joint contact stresses (under some more or less arbitrary condition) as a surrogate of the relevant mechanical history. Contact stresses have been estimated in vitro in many joints and in a number of species, although only rarely in vivo. Despite a number of widely varying techniques (and spatial resolutions) to measure these contact stresses, reported ranges of static peak normal stresses are relatively similar from joint to joint across species, and in the range of 0.5 to 5.0 MPa. This suggests vertebrate diarthrodial joints have evolved to achieve similar mechanical design criteria. Available evidence also suggests some disorders of cartilage deterioration are associated with somewhat higher peak pressures ranging from 1-20 MPa, but overlapping the range of normal pressures. Some evidence and considerable logic suggests static contact stresses per se do not predict cartilage responses, but rather temporal aspects of the contact stress history. Static contact stresses may therefore not be a reasonable surrogate for biomechanical studies. Rather, temporal and spatial aspects of the loading history undoubtedly induce beneficial and deleterious biological responses. Finally, since all articular cartilage experiences similar stresses, the concept of a "weight-bearing" versus a "non-weight-bearing" joint seems flawed, and should be abandoned. PMID:16089079

  2. Outlook export contacts and groups Migrate Outlook Contacts to gmail

    E-print Network

    Aalberts, Daniel P.

    Outlook export contacts and groups Migrate Outlook Contacts to gmail 1. In Outlook 2007 on the File. 4. In the folder list, click the Contacts folder, and then click Next. #12;5. Browse to the folder where you want to save the contacts as a .csv file (your Documents folder or the Desktop folder would

  3. Pustular irritant contact dermatitis caused by dexpanthenol in a child.

    PubMed

    Gulec, Ali Ihsan; Albayrak, Hulya; Uslu, Esma; Ba?kan, Elife; Aliagaoglu, Cihangir

    2015-03-01

    Pustular irritant contact dermatitis is rare and unusual clinic form of contact dermatitis. Dexpanthenol is the stable alcoholic analogue of pantothenic acid. It is widely used in cosmetics and topical medical products for several purposes. We present the case of 8-year-old girl with pustules over erythematous and eczematous areas on the face and neck. To the best of our knowledge, this is the first case reported that is diagnosed as pustular irritant contact dermatitis caused by dexpanthenol. PMID:24506320

  4. Solar cell contacts

    NASA Technical Reports Server (NTRS)

    Meier, D. L.; Campbell, R. B.; Davis, J. R., Jr.; Rai-Choudhury, P.; Sienkiewicz, L. J.

    1982-01-01

    Two experimental contact systems were examined and compared to a baseline contact system consisting of evaporated layers of titanium, palladium, and silver and an electroplated layer of copper. The first experimental contact system consisted of evaporated layers of titanium, nickel, and copper and an electroplated layer of copper. This system performed as well as the baseline system in all respects, including its response to temperature stress tests, to a humidity test, and to an accelerated aging test. In addition, the cost of this system is estimated to be only 43 percent of the cost of the baseline system at a production level of 25 MW/year. The second experimental contact system consisted of evaporated layers of nickel and copper and an electroplated layer of copper. Cells with this system show serious degradation in a temperature stress test at 350 C for 30 minutes. Auger electron spectroscopy was used to show that the evaporated nickel layer is not an adequate barrier to copper diffusion even at temperatures as low as 250 C. This fact brings into question the long-term reliability of this contact system.

  5. Maraba Virus as a Potent Oncolytic Vaccine Vector

    PubMed Central

    Pol, Jonathan G; Zhang, Liang; Bridle, Byram W; Stephenson, Kyle B; Rességuier, Julien; Hanson, Stephen; Chen, Lan; Kazdhan, Natasha; Bramson, Jonathan L; Stojdl, David F; Wan, Yonghong; Lichty, Brian D

    2014-01-01

    The rhabdovirus Maraba has recently been characterized as a potent oncolytic virus. In the present study, we engineered an attenuated Maraba strain, defined as MG1, to express a melanoma-associated tumor antigen. Its ability to mount an antitumor immunity was evaluated in tumor-free and melanoma tumor-bearing mice. Alone, the MG1 vaccine appeared insufficient to prime detectable adaptive immunity against the tumor antigen. However, when used as a boosting vector in a heterologous prime-boost regimen, MG1 vaccine rapidly generated strong antigen-specific T-cell immune responses. Once applied for treating syngeneic murine melanoma tumors, our oncolytic prime-boost vaccination protocol involving Maraba MG1 dramatically extended median survival and allowed complete remission in more than 20% of the animals treated. This work describes Maraba virus MG1 as a potent vaccine vector for cancer immunotherapy displaying both oncolytic activity and a remarkable ability to boost adaptive antitumor immunity. PMID:24322333

  6. Structure-activity relationship of flavonoids as potent inhibitors of carbonyl reductase 1 (CBR1).

    PubMed

    Arai, Yuki; Endo, Satoshi; Miyagi, Namiki; Abe, Naohito; Miura, Takeshi; Nishinaka, Toru; Terada, Tomoyuki; Oyama, Masayoshi; Goda, Hiroaki; El-Kabbani, Ossama; Hara, Akira; Matsunaga, Toshiyuki; Ikari, Akira

    2015-03-01

    Human carbonyl reductase 1 (CBR1), a member of the short-chain dehydrogenase/reductase superfamily, reduces a variety of carbonyl compounds including therapeutic drugs. CBR1 is involved in the reduction of the anthracycline anticancer drugs to their less anticancer C-13 hydroxy metabolites, which are cardiotoxic. CBR1 inhibitors are thought to be promising agents for adjuvant therapy with twofold beneficial effect in prolonging the anticancer efficacy of the anthracyclines while decreasing cardiotoxicity, a side effect of the drugs. In this study, we evaluated 27 flavonoids for their inhibitory activities of CBR1 in order to explore the structure-activity relationship (SAR). Among them, luteolin (2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-1-benzopyran-4-one) showed the most potent inhibition (IC5095nM), which is also more potent compared to all known classes of CBR1 inhibitors. The inhibition of luteolin was noncompetitive with respect to the substrate in the NADPH-dependent reduction direction, but CBR1 exhibited moderate NADP(+)-dependent dehydrogenase activity for some alicyclic alcohols, in which the luteolin inhibition was competitive with respect to the alcohol substrate (Ki59nM). The SAR of the flavonoids indicated that the 7-hydroxy group of luteolin was responsible for the potent inhibition of CBR1. The molecular docking of luteolin in CBR1-NADPH complex showed that theflavonoid binds to the substrate-binding cleft, in which its 7-hydroxy group formed a H-bond with main-chain oxygen of Met234, in addition to H-bond interactions (of its 5-hydroxy and 4-carbonyl groups with catalytically important residues Tyr193 and/or Ser139) and a ?-stacking interaction (between its phenyl ring and Trp229). PMID:25549925

  7. Expanded Human Blood-Derived ??T Cells Display Potent Antigen-Presentation Functions

    PubMed Central

    Khan, Mohd Wajid A.; Curbishley, Stuart M.; Chen, Hung-Chang; Thomas, Andrew D.; Pircher, Hanspeter; Mavilio, Domenico; Steven, Neil M.; Eberl, Matthias; Moser, Bernhard

    2014-01-01

    Cell-based immunotherapy strategies target tumors directly (via cytolytic effector cells) or aim at mobilizing endogenous anti-tumor immunity. The latter approach includes dendritic cells (DC) most frequently in the form of in vitro cultured peripheral blood monocytes-derived DC. Human blood ??T cells are selective for a single class of non-peptide agonists (“phosphoantigens”) and develop into potent antigen-presenting cells (APC), termed ??T-APC within 1–3?days of in vitro culture. Availability of large numbers of ??T-APC would be advantageous for use as a novel cellular vaccine. We here report optimal ??T cell expansion (>107 cells/ml blood) when peripheral blood mononuclear cells (PBMC) from healthy individuals and melanoma patients were stimulated with zoledronate and then cultured for 14?days in the presence of IL-2 and IL-15, yielding ??T cell cultures of variable purity (77?±?21 and 56?±?26%, respectively). They resembled effector memory ??T (TEM) cells and retained full functionality as assessed by in vitro tumor cell killing as well as secretion of pro-inflammatory cytokines (IFN?, TNF?) and cell proliferation in response to stimulation with phosphoantigens. Importantly, day 14 ??T cells expressed numerous APC-related cell surface markers and, in agreement, displayed potent in vitro APC functions. Day 14 ??T cells from PBMC of patients with cancer were equally effective as their counterparts derived from blood of healthy individuals and triggered potent CD8+ ??T cell responses following processing and cross-presentation of simple (influenza M1) and complex (tuberculin purified protein derivative) protein antigens. Of note, and in clear contrast to peripheral blood ??T cells, the ability of day 14 ??T cells to trigger antigen-specific ??T cell responses did not depend on re-stimulation. We conclude that day 14 ??T cell cultures provide a convenient source of autologous APC for use in immunotherapy of patients with various cancers. PMID:25101086

  8. A naturally occurring naringenin derivative exerts potent bone anabolic effects by mimicking oestrogen action on osteoblasts

    PubMed Central

    Swarnkar, Gaurav; Sharan, Kunal; Siddiqui, Jawed A; Mishra, Jay Sharan; Khan, Kainat; Khan, Mohd Parvez; Gupta, Varsha; Rawat, Preeti; Maurya, Rakesh; Dwivedi, Anil K; Sanyal, Sabyasachi; Chattopadhyay, Naibedya

    2012-01-01

    BACKGROUND AND PURPOSE Naringenin and its derivatives have been assessed in bone health for their oestrogen-‘like’ effects but low bioavailability impedes clinical potential. This study was aimed at finding a potent form of naringenin with osteogenic action. EXPERIMENTAL APPROACH Osteoblast cultures were harvested from mouse calvaria to study differentiation by naringenin, isosakuranetin, poncirin, phloretin and naringenin-6-C-glucoside (NCG). Balb/cByJ ovariectomized (OVx) mice without or with osteopenia were given naringenin, NCG, 17?-oestradiol (E2) or parathyroid hormone (PTH). Efficacy was evaluated by bone microarchitecture using microcomputed tomography and determination of new bone formation by fluorescent labelling of bone. Plasma levels of NCG and naringenin were determined by HPLC. KEY RESULTS NCG stimulated osteoblast differentiation more potently than naringenin, while isosakuranetin, poncirin or phloretin had no effect. NCG had better oral bioavailability than naringenin. NCG increased the mRNA levels of oestrogen receptors (ERs) and bone morphogenetic protein (an ER responsive gene) in vivo, more than naringenin. In OVx mice, NCG treatment in a preventive protocol increased bone formation rate (BFR) and improved trabecular microarchitecture more than naringenin or E2. In osteopenic mice, NCG but not naringenin, in a therapeutic protocol, increased BFR and improved trabecular microarchitecture, comparable with effects of PTH treatment. Stimulatory effects of NCG on osteoblasts were abolished by an ER antagonist. NCG transactivated ER? but not ER?. NCG exhibited no uterine oestrogenicity unlike naringenin. CONCLUSIONS AND IMPLICATIONS NCG is a potent derivative of naringenin that has bone anabolic action through the activation of osteoblast ERs and exhibited substantial oral bioavailability. PMID:21864313

  9. Witnessing Violence Toward Siblings: An Understudied but Potent Form of Early Adversity

    Microsoft Academic Search

    Martin H. Teicher; Gordana D. Vitaliano

    2011-01-01

    Research on the consequences of witnessing domestic violence has focused on inter-adult violence and most specifically on violence toward mothers. The potential consequences of witnessing violence to siblings have been almost entirely overlooked. Based on clinical experience we sought to test the hypothesis that witnessing violence toward siblings would be as consequential as witnessing violence toward mothers. The community sample

  10. Potent Inhibition of HIV1 Replication by a Tat Mutant

    Microsoft Academic Search

    Luke W. Meredith; Haran Sivakumaran; Lee Major; Andreas Suhrbier; David Harrich; Linqi Zhang

    2009-01-01

    Herein we describe a mutant of the two-exon HIV-1 Tat protein, termed Nullbasic, that potently inhibits multiple steps of the HIV-1 replication cycle. Nullbasic was created by replacing the entire arginine-rich basic domain of wild type Tat with glycine\\/alanine residues. Like similarly mutated one-exon Tat mutants, Nullbasic exhibited transdominant negative effects on Tat-dependent transactivation. However, unlike previously reported mutants, we

  11. RFI641, a Potent Respiratory Syncytial Virus Inhibitor

    Microsoft Academic Search

    Clayton C. Huntley; William J. Weiss; Anna Gazumyan; Aron Buklan; Boris Feld; William Hu; Thomas R. Jones; Timothy Murphy; Antonia A. Nikitenko; Bryan O'Hara; Gregory Prince; Susan Quartuccio; Yuri E. Raifeld; Philip Wyde; John F. O'Connell

    2002-01-01

    Human respiratory syncytial virus (RSV), a paramyxovirus, is a major cause of acute upper and lower respiratory tract infections in infants, young children, and adults. RFI-641 is a novel anti-RSV agent with potent in vitro and in vivo activity. RFI-641 is active against both RSV type A and B strains. The viral specificity and the large therapeutic window of RFI-641

  12. Potent Heterologous Antifungal Proteins from Cheeseweed ( Malva parviflora)

    Microsoft Academic Search

    Xing Wang; Greg J. Bunkers

    2000-01-01

    Two novel antifungal proteins were purified and characterized from cheeseweed (Malva parviflora). Both proteins, designated CW-1 and CW-2, are composed of two different subunits of 5000 and 3000 Da, respectively. These proteins possess very potent antifungal activities, and more interestingly the inhibition is fungicidal instead of fungistatic. At low salt condition, the IC50 of CW-1 and CW-2 against Fusarium graminearum

  13. A novel potent vasoconstrictor peptide produced by vascular endothelial cells

    Microsoft Academic Search

    Masashi Yanagisawa; Hiroki Kurihara; Sadao Kimura; Yoko Tomobe; Mieko Kobayashi; Youji Mitsui; Yoshio Yazaki; Katsutoshi Goto; Tomoh Masaki

    1988-01-01

    An endothelium-derived 21-residue vasoconstrictor peptide, endothelin, has been isolated, and shown to be one of the most potent vasoconstrictors known. Cloning and sequencing of preproendothelin complementary DNA shows that mature endothelin is generated through an unusual proteolytic processing, and regional homologies to a group of neurotoxins suggest that endothelin is an endogenous modulator of voltage-dependent ion channels. Expression of the

  14. Potent Urea and Carbamate Inhibitors of Soluble Epoxide Hydrolases

    Microsoft Academic Search

    Christophe Morisseau; Marvin H. Goodrow; Deanna Dowdy; Jiang Zheng; Jessica F. Greene; James R. Sanborn; Bruce D. Hammock

    1999-01-01

    The soluble epoxide hydrolase (sEH) plays a significant role in the biosynthesis of inflammation mediators as well as xenobiotic transformations. Herein, we report the discovery of substituted ureas and carbamates as potent inhibitors of sEH. Some of these selective, competitive tightbinding inhibitors with nanomolar Ki values interacted stoichiometrically with the homogenous recombinant murine and human sEHs. These inhibitors enhance cytotoxicity

  15. Amphibian glucagon family peptides: potent metabolic regulators in fish hepatocytes

    Microsoft Academic Search

    Thomas P Mommsen; J. Michael Conlon; David M Irwin

    2001-01-01

    Peptides analogous to glucagon-like peptide-1 (GLP-1) have been isolated from amphibian pancreas and intestine, and their amino acid sequences and cDNA structures elucidated. Just like their mammalian counterpart, these peptides are potent insulinotropins in mammalian pancreatic cells. We show here that these peptides also exert strong glycogenolytic actions when applied to dispersed fish hepatocytes. We compared the potencies of three

  16. Dynorphin(1-13), an Extraordinarily Potent Opioid Peptide

    Microsoft Academic Search

    Avram Goldstein; S. Tachibana; L. I. Lowney; M. Hunkapiller; L. Hood

    1979-01-01

    We describe the opioid properties of a tridecapeptide, the sequence of which corresponds to the NH2-terminal sequence of dynorphin, a novel porcine pituitary endorphin. It contains [Leu]enkephalin. In the guinea pig ileum longitudinal muscle preparation it is about 700 times more potent than [Leu]enkephalin. Its effects in this tissue are blocked completely by naloxone, but the apparent affinity of naloxone

  17. Formation of gold contact pads on superconducting films by laser ablation

    NASA Astrophysics Data System (ADS)

    Pozygun, I. S.; Seropyan, G. M.; Sychev, S. A.; Fedosov, D. V.

    2015-02-01

    Formation of gold contact pads on dielectric substrates by laser ablation is studied. The mechanical and conductive properties of such contact pads provide a reliable electrical contact between superconducting YBa2Cu3O7 - x (YBCO) films (and YBCO-based structures) and add-on electronic components. The contact pads are formed on the substrate before superconducting film deposition. A high adhesion of the contact pad is provided owing to the deep penetration of laser plasma particles into the substrate.

  18. Shoe allergic contact dermatitis.

    PubMed

    Matthys, Erin; Zahir, Amir; Ehrlich, Alison

    2014-01-01

    Foot dermatitis is a widespread condition, affecting men and women of all ages. Because of the location, this condition may present as a debilitating problem to those who have it. Allergic contact dermatitis involving the feet is frequently due to shoes or socks. The allergens that cause shoe dermatitis can be found in any constituent of footwear, including rubber, adhesives, leather, dyes, metals, and medicaments. The goal of treatment is to identify and minimize contact with the offending allergen(s). The lack of product information released from shoe manufacturers and the continually changing trends in footwear present a challenge in treating this condition. The aim of this study is to review the current literature on allergic contact shoe dermatitis; clinical presentation, allergens, patch testing, and management will be discussed. PubMed and MEDLINE databases were used for the search, with a focus on literature updates from the last 15 years. PMID:25000234

  19. Contact sensitization in children.

    PubMed

    Manzini, B M; Ferdani, G; Simonetti, V; Donini, M; Seidenari, S

    1998-01-01

    Our study concerns contact sensitization in children, the frequency of which is still debated in the literature, even though specific reports are increasing. During a 7 year period (1988-1994) 670 patients, 6 months to 12 years of age, were patch tested with the European standard series, integrated with 24 haptens, at the same concentrations as for adults. We observed positive results in 42% of our patients. Thimerosal, nickel sulfate, Kathon CG, fragrance mix, neomycin, wool alcohols, and ammoniated mercury induced most of the positive responses. The highest sensitization rate was found in children from 0 to 3 years of age. Comments on main positive haptens are reported. Seventy-seven percent of our sensitized patients were atopics, suggesting that atopy represents a predisposing factor for contact hypersensitivity. Patch testing represents a useful diagnostic procedure for the definition of childhood eczematous dermatitis and for the identification of agents inducing contact sensitization which is frequently associated with atopic dermatitis. PMID:9496796

  20. 40 CFR 463.10 - Applicability; description of the contact cooling and heating water subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...CONTINUED) EFFLUENT GUIDELINES AND STANDARDS PLASTICS MOLDING AND FORMING POINT SOURCE CATEGORY Contact...processes where process water comes in contact with plastic materials or plastic products for the purpose of heat transfer...

  1. 40 CFR 463.10 - Applicability; description of the contact cooling and heating water subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...CONTINUED) EFFLUENT GUIDELINES AND STANDARDS PLASTICS MOLDING AND FORMING POINT SOURCE CATEGORY Contact...processes where process water comes in contact with plastic materials or plastic products for the purpose of heat transfer...

  2. Contact hypothesis in ethnic relations

    Microsoft Academic Search

    Yehuda Amir

    1969-01-01

    Reviews research regarding the effects of intergroup contact on ethnic relations. The investigations discussed include both intra- and cross-cultural studies involving contact between various ethnic groups. The principles and generalizations emerging from these studies are categorized under (1) opportunities for contact, (2) the principle of equal status, (3) contact with high-status representatives of a minority group, (4) cooperative and competitive

  3. Fabrication of High-Quality Co2FeSi/SiO x N y /Si(100) Tunnel Contacts Using Radical-Oxynitridation-Formed SiO x N y Barrier for Si-Based Spin Transistors

    NASA Astrophysics Data System (ADS)

    Takamura, Yota; Hayashi, Kengo; Shuto, Yusuke; Sugahara, Satoshi

    2012-05-01

    A high-quality Co2FeSi (CFS)/SiO x N y /Si tunnel junction was fabricated, in which the SiO x N y barrier layer was formed by radical oxynitridation of an Si(100) substrate and the CFS electrode was formed by silicidation of an Fe/Co/amorphous-Si multilayer deposited on the barrier layer. The ultrathin SiO x N y barrier layer completely blocked diffusion of Co and Fe atoms into the Si substrate during rapid thermal annealing (RTA) for the silicidation. X-ray diffraction investigations clarified that the CFS film on the ultrathin SiO x N y barrier layer exhibited a highly (110)-oriented texture structure and that the film had the L21 structure with a high degree of L21 order. High resolution cross-sectional transmission electron microscopy investigations revealed that the CFS/SiO x N y interface was atomically flat and that the crystal lattice of the CFS film was directly grown on the SiO x N y surface without degradation of the crystallinity at the interface.

  4. Adhesive strength of glass composite materials in the contact region

    Microsoft Academic Search

    B. S. Batalin; H. A. Pravina

    1992-01-01

    at a particular temperature. In this state the glass wets the surface particles of the two phases. The structure of the region of contact between the glass and the two phases is formed as a result of interactions between the glass and the two phases. For subsequent crystallization of the matrix this structure changes. The properties of the contact region

  5. Contact fatigue behavior of PVD-coated hardmetals

    Microsoft Academic Search

    E. Tarrés; G. Ramírez; Y. Gaillard; E. Jiménez-Piqué; L. Llanes

    2009-01-01

    There is an increasing usage of PVD-coated hardmetals in applications where contact loads of cyclic nature between curved surfaces are common, e.g. cold forming tools and machine components. Thus, knowledge of both the mechanical response and the damage mechanisms involved during contact fatigue of these systems is required if they want to be used effectively. In this investigation this is

  6. Electrical Characteristics of Contacts Contaminated with Silver Sulfide Film

    Microsoft Academic Search

    GEORGE J. RUSS

    1970-01-01

    Frequently the electrical performance of silver contacts is impaired by the unavoidable growth of a sulfide film on the mating contact surfaces. In the case where one or both of the electrodes are silver, or partly silver, and a silver sulfide film is formed on one or both of the electrodes, the electrical performance is greatly deteriorated and is among

  7. Spanish in Four Continents: Studies in Language Contact and Bilingualism.

    ERIC Educational Resources Information Center

    Silva-Corvalan, Carmen, Ed.

    Papers on Spanish bilingualism and Spanish in contact with other languages include: "The Study of Language Contact: An Overview of the Issues" (Carmen Silva-Corvalan); "Language Mixture: Ordinary Processes, Extraordinary Results" (Sarah G. Thomason); "The Impact of Quichua on Verb Forms Used in Spanish Requests in Otavalo, Ecuador" (Joni Kay…

  8. Linking the customer contact model to service quality

    Microsoft Academic Search

    Andreas C Soteriou; Richard B Chase

    1998-01-01

    One of the defining characteristics of services is the existence of some form of contact between the customer and the service firm during the service production process. In the 1980s, customer contact (CC) became an important dimension in virtually all service taxonomies. Its importance to perceived service quality (SQ) was also recognized, but the direct linkage between CC and SQ

  9. Effects of nanosized contact spots on thermal contact resistance

    NASA Astrophysics Data System (ADS)

    Lee, Sangyoung; Jang, Yong Hoon; Kim, Woochul

    2008-04-01

    We investigate the effects of nanosized contact spots on the thermal contact resistance (TCR) in multiscale contacts. As the contact size decreases below the phonon mean free path, the thermal conductivity varies with the size of the contact and is not the same as its bulk counterpart. We take this into account in our model and we calculate the TCR of silicon contacted with other silicon. The TCR increases as the number of nanosized contact spots increases. However, if we do not consider the thermal conductivity reduction as the contact size decreases below the size of the phonon mean free path, there is a finite limit of the TCR. A parametric study on the effects of distance and size of the contact spots is also presented.

  10. Structural Permutation of Potent Cytotoxin, Polytheonamide B: Discovery of Cytotoxic Peptide with Altered Activity

    PubMed Central

    2012-01-01

    Polytheonamide B (1) is an ion-channel forming natural peptide with a d,l-alternating 48 amino acid sequence, which is an exceedingly potent cytotoxin. We recently designed and synthesized a simplified dansylated polytheonamide mimic 2, in which six amino acid residues were modified from 1, and demonstrated that 2 emulated the functions of 1. Here we report a comprehensive structure–activity relationship study of substructures of 2. A unified synthetic strategy was developed for highly automated syntheses of 13 peptide sequences of 27 to 39 amino acid residues, and the artificial 37-mer peptide 6 was discovered to be significantly more toxic than the other 12 compounds toward P388 mouse leukemia cells (IC50 = 3.7 nM). Ion exchange activity experiments of 6 using the liposome and P388 cells both demonstrated that 6 did not possess ion-channel activity, strongly suggesting that 6 exerted its potent cytoxicity through a distinct mode of action from 1 and 2. PMID:24900563

  11. Discovery of the highly potent fluoroquinolone-based benzothiazolyl-4-thiazolidinone hybrids as antibacterials.

    PubMed

    Patel, Rahul V; Park, Se Won

    2014-07-01

    A new series of fluoroquinolone-based benzothiazolyl-4-thiazolidinone hybrids has been yielded via sulfated tungstate-promoted highly accelerated N-formylation at a piperazine residue of ciprofloxacin and norfloxacin entities. The formylated fluoroquinolone moieties were then coupled with substituted 2-aminobenzothiazoles, which were generated from their respective para-substituted amines to form corresponding Schiff base intermediates. The Schiff bases were then treated with thioglycolic acid to equip a new class of 4-thiazolidinones to be analyzed for their antibacterial effects against two Gram-positive (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacterial strains and were found highly potent with lowest Minimum inhibitory concentrations (MIC), 1-2 ?g/mL, that is, more potent than control drugs ciprofloxacin (3.12-6.25 ?g/mL). Initial outcomes provided for these novel molecular systems will aid researchers to design and develop new antibacterial drugs. The structural assignments of the new products were done on the basis of FT-IR, (1) H NMR and (13) C NMR spectroscopy, and elemental analysis. PMID:24524270

  12. Construction of humanized anti-ganglioside monoclonal antibodies with potent immune effector functions.

    PubMed

    Nakamura, K; Tanaka, Y; Shitara, K; Hanai, N

    2001-07-01

    Gangliosides GD3, GD2 and GM2, which are the major gangliosides expressed on most human cancers of neuroectodermal and epithelial origin, have been focused on as effective targets for passive immunotherapy with monoclonal antibodies. We previously developed a chimeric anti-GD3 mAb, KM871, and a humanized anti-GM2 mAb, KM8969, which specifically bound to the respective antigen with high affinity and showed potent immune effector functions. Humanization of anti-ganglioside antibody is expected to enhance its use for human cancer therapy. In the present study, we generated a chimeric anti-GD2 mAb, KM1138, and further developed the humanized form of anti-GD2 and anti-GD3 mAbs by the complementarity-determining regions grafting method. The resultant humanized anti-GD2 mAb, KM8138, and anti-GD3 mAb, KM8871, showed binding affinity and specificity similar to those of their chimeric counterparts. In addition, both humanized mAbs had functional potency comparable to the chimeric mAbs in mediating the immune effector functions, consisting of antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity. The production of these humanized anti-ganglioside mAbs, with potent effector functions and low immunogenicity, precedes the evaluation of the therapeutic value of anti-ganglioside mAbs in passive immunotherapy and the target validation for ganglioside-based vaccine therapy. PMID:11499811

  13. Increased Resistance of Contact Lens-Related Bacterial Biofilms to Antimicrobial Activity of Soft Contact Lens Care Solutions

    Microsoft Academic Search

    Loretta B. Szczotka-Flynn; Yoshifumi Imamura; Jyotsna Chandra; Changping Yu; Pranab K. Mukherjee; Eric Pearlman; Mahmoud A. Ghannoum

    2009-01-01

    Purpose: To determine if clinical and reference strains of Pseudomonas aeruginosa, Serratia marcescens, and Staphylococcus aureus form biofilms on silicone hydrogel contact lenses and ascertain antimicrobial activities of contact lens care solutions. Methods: Clinical and American Type Culture Collection reference strains of P. aeruginosa, S. marcescens, and S. aureus were incubated with lotrafilcon A lenses under conditions that facilitate biofilm

  14. Mercury Contact Micromechanical Relays

    Microsoft Academic Search

    Joonwon Kim; Jonathan Simon; Scott Saffer

    This paper presents the use of mercury microdrop (microns in diameter) as a contact in micromechanical relays in microelectromechanical systems (MEMS). Mercury microdrops can be deposited on lithographica lly defined sites on surface by the technique and apparatus developed in UCLA Micromanufacturing Laboratory. Three different micro mercury relays are described. First device has a mercury microdrop in a channel, which

  15. Secure Core Contact Information

    E-print Network

    Secure Core Contact Information C. E. Irvine irvine@nps.edu 831-656-2461 Department of Computer for the secure management of local and/or remote information in multiple contexts. The SecureCore project Science Graduate School of Operations and Information Sciences www.cisr.nps.edu Project Description

  16. Research Contacts: Laura Higgins

    E-print Network

    higher than for teens starting their school day an hour later. #12;Drowsy Driving Research Contacts of any age, but the problem is particularly severe for teens and young adults, in part because young in Virginia noted that the weekday crash rate for students begin- ning school at 7:20 a.m. was 41 percent

  17. Technology Advertising Contact Information

    E-print Network

    Peters, Richard

    Overview #12;Technology Advertising Contact Information Alex Sheath 8596 4063 asheath Overview Our online Technology section is geared towards an IT professional environment, reaching a range of technology enthusiasts from every day gadget consumers to business decision makers where enterprise solutions

  18. Contact - Team Science Toolkit

    Cancer.gov

    The Team Science Toolkit was developed, and is maintained, by the Science of Team Science (SciTS) team at the National Cancer Institute, Division of Cancer Control and Population Science, Behavioral Research Program. To contact us, please email Dr. Kara L.

  19. Thermal Contact Conductance

    NASA Technical Reports Server (NTRS)

    Salerno, Louis J.; Kittel, Peter

    1997-01-01

    The performance of cryogenic instruments is often a function of their operating temperature. Thus, designers of cryogenic instruments often are required to predict the operating temperature of each instrument they design. This requires accurate thermal models of cryogenic components which include the properties of the materials and assembly techniques used. When components are bolted or otherwise pressed together, a knowledge of the thermal performance of such joints are also needed. In some cases, the temperature drop across these joints represents a significant fraction of the total temperature difference between the instrument and its cooler. While extensive databases exist on the thermal properties of bulk materials, similar databases for pressed contacts do not. This has often lead to instrument designs that avoid pressed contacts or to the over-design of such joints at unnecessary expense. Although many people have made measurements of contact conductances at cryogenic temperatures, this data is often very narrow in scope and even more often it has not been published in an easily retrievable fashion, if published at all. This paper presents a summary of the limited pressed contact data available in the literature.

  20. [Contact allergies in musicians].

    PubMed

    Gasenzer, E R; Neugebauer, E A M

    2012-12-01

    During the last years, the problem of allergic diseases has increased. Allergies are errant immune responses to a normally harmless substance. In musicians the allergic contact dermatitis to exotic woods is a special problem. Exotic rosewood contains new flavonoids, which trigger an allergic reaction after permanent contact with the instrument. High quality woodwind instruments such as baroque flute or clarinets are made in ebony or palisander because of its great sound. Today instruments for non-professional players are also made in these exotic materials and non-professionals may have the risk to develop contact dermatitis, too. Brass-player has the risk of an allergic reaction to the different metals contained in the metal sheets of modern flutes and brass instruments. Specially nickel and brass alloys are used to product flute tubes or brass instruments. Special problem arises in children: patients who are allergic to plants or foods have a high risk to develop contact dermatitis. Parents don't know the materials of low-priced instruments for beginners. Often unknown cheap woods from exotic areas are used. Low-priced brass instruments contain high amount of brass and other cheap metals. Physicians should advice musician-patients or parents about the risks of the different materials and look for the reason of eczema on mouth, face, or hands. PMID:23233303

  1. CCG Contact & Staff

    Cancer.gov

    Posted: April 13, 2015 Posted: April 13, 2015 CCG Contact & Staff Center for Cancer Genomics 31 Center Drive, Room 10A11 Bethesda, MD 20892 Email: NCICCGenomics@mail.nih.gov Center for Cancer Genomics Office of the Director Louis M. Staudt, M.D.,

  2. Multigrid contact detection method

    NASA Astrophysics Data System (ADS)

    He, Kejing; Dong, Shoubin; Zhou, Zhaoyao

    2007-03-01

    Contact detection is a general problem of many physical simulations. This work presents a O(N) multigrid method for general contact detection problems (MGCD). The multigrid idea is integrated with contact detection problems. Both the time complexity and memory consumption of the MGCD are O(N) . Unlike other methods, whose efficiencies are influenced strongly by the object size distribution, the performance of MGCD is insensitive to the object size distribution. We compare the MGCD with the no binary search (NBS) method and the multilevel boxing method in three dimensions for both time complexity and memory consumption. For objects with similar size, the MGCD is as good as the NBS method, both of which outperform the multilevel boxing method regarding memory consumption. For objects with diverse size, the MGCD outperform both the NBS method and the multilevel boxing method. We use the MGCD to solve the contact detection problem for a granular simulation system based on the discrete element method. From this granular simulation, we get the density property of monosize packing and binary packing with size ratio equal to 10. The packing density for monosize particles is 0.636. For binary packing with size ratio equal to 10, when the number of small particles is 300 times as the number of big particles, the maximal packing density 0.824 is achieved.

  3. Does Contact Area Matter?

    NSDL National Science Digital Library

    2014-09-18

    Using the same method for measuring friction that was used in the previous lesson (Discovering Friction), students design and conduct experiments to determine if the amount of area over which an object contacts a surface it is moving across affects the amount of friction encountered.

  4. Obituary--rigid contact lenses.

    PubMed

    Efron, Nathan

    2010-10-01

    Scleral and corneal rigid lenses represented 100 per cent of the contact lens market immediately prior to the invention of soft lenses in the mid-1960s. In the United Kingdom today, rigid lenses comprise 2 per cent of all new lens fits. Low rates of rigid lens fitting are also apparent in 27 other countries which have recently been surveyed. Thus, the 1998 prediction of the author that rigid lenses--also referred to as 'rigid gas permeable' (RGP) lenses or 'gas permeable' (GP) lenses--would be obsolete by the year 2010 has essentially turned out to be correct. In this obituary, the author offers 10 reasons for the demise of rigid lens fitting: initial rigid lens discomfort; intractable rigid lens-induced corneal and lid pathology; extensive soft lens advertising; superior soft lens fitting logistics; lack of rigid lens training opportunities; redundancy of the rigid lens 'problem solver' function; improved soft toric and bifocal/varifocal lenses; limited uptake of orthokeratology; lack of investment in rigid lenses; and the emergence of aberration control soft lenses. Rigid lenses are now being fitted by a minority of practitioners with specialist skills/training. Certainly, rigid lenses can no longer be considered as a mainstream form of contact lens correction. May their dear souls (bulk properties) rest in peace. PMID:20674469

  5. Ohmic contact formation on n-type Ge

    NASA Astrophysics Data System (ADS)

    Lieten, R. R.; Degroote, S.; Kuijk, M.; Borghs, G.

    2008-01-01

    Severe Fermi level pinning at the interface between n-Ge and a metal leads to the formation of a Schottky barrier, almost independent on the metal work function. Therefore, it seems impossible to form metal Ohmic contacts on moderately, n-type doped Ge layers. For p-type Ge, the Fermi level pinning works opposite: all metal contacts show Ohmic behavior. This fixed behavior can be altered by the introduction of a thin Ge3N4 layer. Ge3N4 seems effective in reducing Fermi level pinning and, therefore, allows the formation of Ohmic contacts on n-type Ge and a rectifying contact on p-type Ge.

  6. Metal Silicides: Active elements of ULSI contacts

    NASA Astrophysics Data System (ADS)

    Osburn, C. M.; Tsai, J. Y.; Sun, J.

    1996-11-01

    As device dimensions scale to the 0.1 urn regime, the self-aligned suicide (SALICIDE) contact technology increasingly becomes an integral part of both the ultra-shallow junction and the metal oxide semiconductor field-effect transistor device itself. This paper will discuss the effect of suicide materials and formation processes on suicide stability, junction consumption, the ability to accurately profile shallow junctions, and contact resistance in series with the channel. The use of suicides as diffusion sources (SADS) provides an important pathway toward optimization of suicide technology. Diffusion of boron and arsenic from nearly epitaxial layers of CoSi2, formed from bilayers of Ti and Co, offer good suicide stability, ultra-shallow, low-leakage junctions, and low contact resistance.

  7. Contact Graph Routing

    NASA Technical Reports Server (NTRS)

    Burleigh, Scott C.

    2011-01-01

    Contact Graph Routing (CGR) is a dynamic routing system that computes routes through a time-varying topology of scheduled communication contacts in a network based on the DTN (Delay-Tolerant Networking) architecture. It is designed to enable dynamic selection of data transmission routes in a space network based on DTN. This dynamic responsiveness in route computation should be significantly more effective and less expensive than static routing, increasing total data return while at the same time reducing mission operations cost and risk. The basic strategy of CGR is to take advantage of the fact that, since flight mission communication operations are planned in detail, the communication routes between any pair of bundle agents in a population of nodes that have all been informed of one another's plans can be inferred from those plans rather than discovered via dialogue (which is impractical over long one-way-light-time space links). Messages that convey this planning information are used to construct contact graphs (time-varying models of network connectivity) from which CGR automatically computes efficient routes for bundles. Automatic route selection increases the flexibility and resilience of the space network, simplifying cross-support and reducing mission management costs. Note that there are no routing tables in Contact Graph Routing. The best route for a bundle destined for a given node may routinely be different from the best route for a different bundle destined for the same node, depending on bundle priority, bundle expiration time, and changes in the current lengths of transmission queues for neighboring nodes; routes must be computed individually for each bundle, from the Bundle Protocol agent's current network connectivity model for the bundle s destination node (the contact graph). Clearly this places a premium on optimizing the implementation of the route computation algorithm. The scalability of CGR to very large networks remains a research topic. The information carried by CGR contact plan messages is useful not only for dynamic route computation, but also for the implementation of rate control, congestion forecasting, transmission episode initiation and termination, timeout interval computation, and retransmission timer suspension and resumption.

  8. Design of potent substrate-analogue inhibitors of canine renin

    NASA Technical Reports Server (NTRS)

    Hui, K. Y.; Siragy, H. M.; Haber, E.

    1992-01-01

    Through a systematic study of structure-activity relationships, we designed potent renin inhibitors for use in dog models. In assays against dog plasma renin at neutral pH, we found that, as in previous studies of rat renin inhibitors, the structure at the P2 position appears to be important for potency. The substitution of Val for His at this position increases potency by one order of magnitude. At the P3 position, potency appears to depend on a hydrophobic side chain that does not necessarily have to be aromatic. Our results also support the approach of optimizing potency in a renin inhibitor by introducing a moiety that promotes aqueous solubility (an amino group) at the C-terminus of the substrate analogue. In the design of potent dog plasma renin inhibitors, the influence of the transition-state residue 4(S)-amino-3(S)-hydroxy-5-cyclohexylpentanoic acid (ACHPA)-commonly used as a substitute for the scissile-bond dipeptide to boost potency-is not obvious, and appears to be sequence dependent. The canine renin inhibitor Ac-paF-Pro-Phe-Val-statine-Leu-Phe-paF-NH2 (compound 15; IC50 of 1.7 nM against dog plasma renin at pH 7.4; statine, 4(S)-amino-3(S)-hydroxy-6-methylheptanoic acid; paF, para-aminophenylalanine) had a potent hypotensive effect when infused intravenously into conscious, sodium-depleted, normotensive dogs. Also, compound 15 concurrently inhibited plasma renin activity and had a profound diuretic effect.

  9. REFERRAL FORM PHONOLOGICAL AWARENESS CLINIC

    E-print Network

    Hickman, Mark

    REFERRAL FORM PHONOLOGICAL AWARENESS CLINIC Concerns regarding communication Please return this form to: Clinical Administrator Email: clinic@cmds.canterbury.ac.nz Department of Communication/s: Home Phone: Work Phone: Mobile Phone: Email: Preferred method of contact during the day: (Between 9am

  10. Chalcone-benzoxaborole hybrid molecules as potent antitrypanosomal agents.

    PubMed

    Qiao, Zhitao; Wang, Qi; Zhang, Fenglong; Wang, Zhongli; Bowling, Tana; Nare, Bakela; Jacobs, Robert T; Zhang, Jiong; Ding, Dazhong; Liu, Yangang; Zhou, Huchen

    2012-04-12

    We report the novel chalcone-benzoxaborole hybrids and their structure-activity relationship against Trypanosoma brucei parasites. The 4-NH(2) derivative 29 and 3-OMe derivative 43 were found to have excellent potency. The synergistic 4-NH(2)-3-OMe compound 49 showed an IC(50) of 0.010 ?g/mL and resulted in 100% survival and zero parasitemia in a murine infection model, which represents one of the most potent compounds discovered to date from the benzoxaborole class that inhibit T. brucei growth. PMID:22360533

  11. Enantioselective Synthesis of (?)-Jiadifenin, a Potent Neurotrophic Modulator

    PubMed Central

    Trzoss, Lynnie; Xu, Jing; Lacoske, Michelle H.; Mobley, William C.; Theodorakis, Emmanuel A.

    2011-01-01

    The first enantioselective synthesis of (?)-jiadifenin (1), a potent neurite outgrowth promoter isolated from Illicium species, is described. The synthetic strategy builds upon bicyclic motif 6 that represents the AB ring of the natural product and proceeds in 19 steps and 1.1% overall yield. Key to our approach is a Mn(III)-mediated oxidation reaction of A ring that, following a regio- and diastereoselective ?-hydroxylation and methylation sequence, produces the desired functionalities of (?)-jiadifenin. The effect of synthetic 1 in NGF-mediated neurite outgrowth was also measured in PC-12 cells. PMID:21812392

  12. Tetrahydroquinoline derivatives as potent and selective factor XIa inhibitors.

    PubMed

    Quan, Mimi L; Wong, Pancras C; Wang, Cailan; Woerner, Francis; Smallheer, Joanne M; Barbera, Frank A; Bozarth, Jeffrey M; Brown, Randi L; Harpel, Mark R; Luettgen, Joseph M; Morin, Paul E; Peterson, Tara; Ramamurthy, Vidhyashankar; Rendina, Alan R; Rossi, Karen A; Watson, Carol A; Wei, Anzhi; Zhang, Ge; Seiffert, Dietmar; Wexler, Ruth R

    2014-02-13

    Antithrombotic agents that are inhibitors of factor XIa (FXIa) have the potential to demonstrate robust efficacy with a low bleeding risk profile. Herein, we describe a series of tetrahydroquinoline (THQ) derivatives as FXIa inhibitors. Compound 1 was identified as a potent and selective tool compound for proof of concept studies. It exhibited excellent antithrombotic efficacy in rabbit thrombosis models and did not prolong bleeding times. This demonstrates proof of concept for the FXIa mechanism in animal models with a reversible, small molecule inhibitor. PMID:24405333

  13. Potent protein glycation inhibition of plantagoside in Plantago major seeds.

    PubMed

    Matsuura, Nobuyasu; Aradate, Tadashi; Kurosaka, Chihiro; Ubukata, Makoto; Kittaka, Shiho; Nakaminami, Yuri; Gamo, Kanae; Kojima, Hiroyuki; Ohara, Mitsuharu

    2014-01-01

    Plantagoside (5,7,4',5'-tetrahydroxyflavanone-3'-O-glucoside) and its aglycone (5,7,3',4',5'-pentahydroxyflavanone), isolated from a 50% ethanol extract of Plantago major seeds (Plantaginaceae), were established to be potent inhibitors of the Maillard reaction. These compounds also inhibited the formation of advanced glycation end products in proteins in physiological conditions and inhibited protein cross-linking glycation. These results indicate that P. major seeds have potential therapeutic applications in the prevention of diabetic complications. PMID:24895551

  14. Fluoxetine Is a Potent Inhibitor of Coxsackievirus Replication

    PubMed Central

    Zuo, Jun; Quinn, Kevin K.; Kye, Steve; Cooper, Paige; Damoiseaux, Robert

    2012-01-01

    No antiviral drugs currently exist for the treatment of enterovirus infections, which are often severe and potentially life threatening. Molecular screening of small molecule libraries identified fluoxetine, a selective serotonin reuptake inhibitor, as a potent inhibitor of coxsackievirus replication. Fluoxetine did not interfere with either viral entry or translation of the viral genome. Instead, fluoxetine and its metabolite norfluoxetine markedly reduced the synthesis of viral RNA and protein. In view of its favorable pharmacokinetics and safety profile, fluoxetine warrants additional study as a potential antiviral agent for enterovirus infections. PMID:22751539

  15. Synthesis and evaluation of bibenzyl glycosides as potent tyrosinase inhibitors.

    PubMed

    Tajima, Reiko; Oozeki, Hiromi; Muraoka, Seiichi; Tanaka, Saori; Motegi, Yukari; Nihei, Hiroyuki; Yamada, Yoichi; Masuoka, Noriyoshi; Nihei, Ken-ichi

    2011-04-01

    Bibenzyl glycosides 1-6 were synthesized from 2,4-dihydoxybenzaldehyde and xylose, glucose, cellobiose or maltose. The key steps in the synthesis were the Wittig reaction and trichloroacetimidate glycosylation. Tests for tyrosinase inhibitory activity showed that all were significantly active, indicating that they are unique hydrophilic tyrosinase inhibitors. Bibenzyl xyloside 2 is a particularly potent inhibitor (IC(50) = 0.43 ?M, 17 times higher than that of kojic acid). These results suggest that the hydrophilic cavity of tyrosinase might accommodate the bulky carbohydrate on the bibenzyl scaffold. PMID:21334791

  16. An efficient synthesis of a potent PPARpan agonist.

    PubMed

    Guo, Jiasheng; Erickson, Greg A; Fitzgerald, Russ N; Matsuoka, Richard T; Rafferty, Stephen W; Sharp, Matthew J; Sickles, Barry R; Wisowaty, James C

    2006-10-13

    An efficient synthesis of 2-{4-[({4-{[4-(4-methoxyphenyl)piperazin-1-yl]methyl}-2-[4-(trifluoromethyl)phenyl]-1,3-thiazol-5-yl}methyl)thio]phenoxy}-2-methylpropanoic acid (1), a potent PPARpan agonist, is described. The seven-step synthesis, which afforded 1 in 30% overall yield, includes a highly regioselective carbon-sulfur bond formation via coupling of a bishydroxymethylthiazole (3) with 4-hydroxythiophenol, displacement of the remaining alcohol through a three-step telescoped sequence involving an efficient cleavage of an aryl mesylate, and an efficient and practical method of introducing an isobutyric acid fragment. PMID:17025332

  17. Molecular dynamics study of contact mechanics: contact area and interfacial separation from small to full contact

    E-print Network

    C. Yang; B. N. J. Persson

    2007-10-01

    We report a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. We study the contact area and the interfacial separation from small contact (low load) to full contact (high load). For small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load. For high load the contact area approaches to the nominal contact area (i.e., complete contact), and the interfacial separation approaches to zero. The present results may be very important for soft solids, e.g., rubber, or for very smooth surfaces, where complete contact can be reached at moderate high loads without plastic deformation of the solids.

  18. Surface coating for blood-contacting devices

    NASA Astrophysics Data System (ADS)

    Nair, Ajit Kumar Balakrishnan

    The major problems always encountered with the blood-contacting surfaces are their compatibility, contact blood damage, and thrombogenicity. Titanium nitride (TiN) is a hard, inert, ceramic material that is widely used in the engineering industry. TiN has been proven to be a good biomaterial in its crystalline form, in orthopedic, and in tissue implant applications. This dissertation describes a method to coat amorphous TiN on the blood-contacting surfaces of certain medical devices using the room-temperature sputtering process and to characterize, to test, and to evaluate the coating for a reliable, durable, and compatible blood-contacting surface The blood-compatibility aspects were evaluated with standard, established protocols and procedures to prove the feasibility. An amorphous TiN coating is developed, characterized, tested, and blood compatibility evaluated by applying to the blood-contacting surfaces of stainless steel, catheters, and blood filters. The flexibility characteristics were proven by applying it to the diaphragms of the pulsatile pneumatic ventricular assist device. The results show that amorphous titanium nitride is flexible and adherent to polymeric substrates like polyurethane and polyester. Blood compatibility evaluation showed comparable results with catheters and superior behavior with stainless steel and polyester filters. It is concluded that amorphous titanium nitride can be considered to be applied to the surfaces of some of the medical devices in order to improve blood compatibility.

  19. /Au Back Contacts

    NASA Astrophysics Data System (ADS)

    Paudel, Naba R.; Compaan, Alvin D.; Yan, Yanfa

    2014-08-01

    We report on the fabrication and characterization of CdTe thin-film solar cells with Cu-free MoO3- x /Au back contacts. CdTe solar cells with sputtered CdTe absorbers of thicknesses from 0.5 to 1.75 ?m were fabricated on Pilkington SnO2:F/SnO2-coated soda-lime glasses coated with a 60- to 80-nm sputtered CdS layer. The MoO3- x /Au back contact layers were deposited by thermal evaporation. The incorporation of MoO3- x layer was found to improve the open circuit voltage ( V OC) but reduce the fill factor of the ultrathin CdTe cells. The V OC was found to increase as the CdTe thickness increased.

  20. Contact dynamics math model

    NASA Technical Reports Server (NTRS)

    Glaese, John R.; Tobbe, Patrick A.

    1986-01-01

    The Space Station Mechanism Test Bed consists of a hydraulically driven, computer controlled six degree of freedom (DOF) motion system with which docking, berthing, and other mechanisms can be evaluated. Measured contact forces and moments are provided to the simulation host computer to enable representation of orbital contact dynamics. This report describes the development of a generalized math model which represents the relative motion between two rigid orbiting vehicles. The model allows motion in six DOF for each body, with no vehicle size limitation. The rotational and translational equations of motion are derived. The method used to transform the forces and moments from the sensor location to the vehicles' centers of mass is also explained. Two math models of docking mechanisms, a simple translational spring and the Remote Manipulator System end effector, are presented along with simulation results. The translational spring model is used in an attempt to verify the simulation with compensated hardware in the loop results.

  1. PRINT, COMPLETE AND PROVIDE SIGNED FORM ALONG WITH ALL REQUIRED

    E-print Network

    PRINT, COMPLETE AND PROVIDE SIGNED FORM ALONG WITH ALL REQUIRED DOCUMENTS TO THE APPROPRIATE OFFICE through the General Manager. REQUEST DETAILS Contact information Group/Office/Organization name: Contact Advancement whose signature appears below. Signature Print Sign Date #12;

  2. 76 FR 29243 - Agency Forms Undergoing Paperwork Reduction Act Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-20

    ...Investigation Outcome Reporting, (2) Optional Measles, Mumps, or Rubella Air/Land Contact...Outcome Reporting Form, (5) Optional Measles, Mumps or Rubella Maritime Contact Investigation...investigation; Tuberculosis (TB), Measles, Mumps, and Rubella or the General...

  3. LANE MEDICAL COPORATE MEMBERSHIP FORM Print legibly and complete

    E-print Network

    Sonnenburg, Justin L.

    AND POLICIES Individuals representing a profit or non-profit company, or those who are self employed, may usLANE MEDICAL COPORATE MEMBERSHIP FORM Print legibly and complete Company Name: ______________________________________________________ Contact Person: ________________________Title of Contact Person: ________________________ Company Address

  4. Contact stress sensor

    SciTech Connect

    Kotovsky, Jack

    2014-02-11

    A method for producing a contact stress sensor that includes one or more MEMS fabricated sensor elements, where each sensor element of includes a thin non-recessed portion, a recessed portion and a pressure sensitive element adjacent to the recessed portion. An electric circuit is connected to the pressure sensitive element. The circuit includes a pressure signal circuit element configured to provide a signal upon movement of the pressure sensitive element.

  5. Contact stress sensor

    DOEpatents

    Kotovsky, Jack (Oakland, CA)

    2012-02-07

    A contact stress sensor includes one or more MEMS fabricated sensor elements, where each sensor element of includes a thin non-recessed portion, a recessed portion and a pressure sensitive element adjacent to the recessed portion. An electric circuit is connected to the pressure sensitive element. The circuit includes a thermal compensator and a pressure signal circuit element configured to provide a signal upon movement of the pressure sensitive element.

  6. Synthesis, molecular modeling, and biological evaluation of novel chiral thiosemicarbazone derivatives as potent anticancer agents.

    PubMed

    Ta?demir, Demet; Karaküçük-?yido?an, Ay?egül; Ula?li, Mustafa; Ta?kin-Tok, Tu?ba; Oruç-Emre, Em?ne Elç?n; Bayram, Hasan

    2015-02-01

    A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF-7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC-27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound exhibited the most potent activity (IC50 4.6??M) against HGC-27 as compared with the reference compound, sindaxel (IC50 10.3??M), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177-188, 2015. © 2014 Wiley Periodicals, Inc. PMID:25399965

  7. Proteolytic processing of QSOX1A ensures efficient secretion of a potent disulfide catalyst

    PubMed Central

    Rudolf, Jana; Pringle, Marie A.; Bulleid, Neil J.

    2013-01-01

    QSOX1 (quiescin sulfhydryl oxidase 1) efficiently catalyses the insertion of disulfide bonds into a wide range of proteins. The enzyme is mechanistically well characterized, but its subcellular location and the identity of its protein substrates remain ill-defined. The function of QSOX1 is likely to involve disulfide formation in proteins entering the secretory pathway or outside the cell. In the present study, we show that this enzyme is efficiently secreted from mammalian cells despite the presence of a transmembrane domain. We identify internal cleavage sites and demonstrate that the protein is processed within the Golgi apparatus to yield soluble enzyme. As a consequence of this efficient processing, QSOX1 is probably functional outside the cell. Also, QSOX1 forms a dimer upon cleavage of the C-terminal domain. The processing of QSOX1 suggests a novel level of regulation of secretion of this potent disulfide catalyst and producer of hydrogen peroxide. PMID:23713614

  8. Functional modular contact lens

    NASA Astrophysics Data System (ADS)

    Shum, Angela J.; Cowan, Melissa; Lähdesmäki, Ilkka; Lingley, Andrew; Otis, Brian; Parviz, Babak A.

    2009-08-01

    Tear fluid offers a potential route for non-invasive sensing of physiological parameters. Utilization of this potential depends on the ability to manufacture sensors that can be placed on the surface of the eye. A contact lens makes a natural platform for such sensors, but contact lens polymers present a challenge for sensor fabrication. This paper describes a microfabrication process for constructing sensors that can be integrated into the structure of a functional contact lens in the future. To demonstrate the capabilities of the process, an amperometric glucose sensor was fabricated on a polymer substrate. The sensor consists of platinum working and counter electrodes, as well as a region of indium-tin oxide (ITO) for glucose oxidase immobilization. An external silver-silver chloride electrode was used as the reference electrode during the characterization experiments. Sensor operation was validated by hydrogen peroxide measurements in the 10- 20 ?M range and glucose measurements in the 0.125-20 mM range.

  9. Graphdiyne-metal contacts and graphdiyne transistors.

    PubMed

    Pan, Yuanyuan; Wang, Yangyang; Wang, Lu; Zhong, Hongxia; Quhe, Ruge; Ni, Zeyuan; Ye, Meng; Mei, Wai-Ning; Shi, Junjie; Guo, Wanlin; Yang, Jinbo; Lu, Jing

    2015-02-01

    Graphdiyne was prepared on a metal surface, and the preparation of devices using it inevitably involves its contact with metals. Using density functional theory with dispersion correction, we systematically studied, for the first time, the interfacial properties of graphdiyne that is in contact with a series of metals (Al, Ag, Cu, Au, Ir, Pt, Ni, and Pd). Graphdiyne forms an n-type Ohmic or quasi-Ohmic contact with Al, Ag, and Cu, while it forms a Schottky contact with Pd, Au, Pt, Ni, and Ir (at the source/drain-channel interface), with high Schottky barrier heights of 0.21, 0.46 (n-type), 0.30, 0.41, and 0.46 (p-type) eV, respectively. A graphdiyne field effect transistor (FET) with Al electrodes was simulated using quantum transport calculations. This device exhibits an on-off ratio up to 10(4) and a very large on-state current of 1.3 × 10(4) mA mm(-1) in a 10 nm channel length. Thus, a new prospect has opened up for graphdiyne in high performance nanoscale devices. PMID:25562182

  10. OGA Institution Points of Contact

    Cancer.gov

    OGA Institution Points of Contact Please contact the grants management specialist assigned to your institution for questions regarding NCI grants. Institution Assigned Specialist FY 2015 3P Biotechnologies, INC. Scharf, Sarah Adheren, INC. Ward, Rosemary Alabama

  11. Ultralow resistance in situ Ohmic contacts to InGaAs/InP Uttam Singisetti,1,a

    E-print Network

    Rodwell, Mark J. W.

    Ultralow resistance in situ Ohmic contacts to InGaAs/InP Uttam Singisetti,1,a Mark A. Wistey,1 contacts using in situ deposition of molybdenum Mo contacts onto n-type In0.53Ga0.47As grown on InP. The contacts were formed by evaporating Mo onto the wafer using an electron beam evaporator connected

  12. Thioxanthines with potent bronchodilator and coronary dilator properties

    PubMed Central

    Armitage, A. K.; Boswood, Janet; Large, B. J.

    1961-01-01

    Some of the pharmacological properties of two new compounds, choline 6-thiotheophyllinate and the choline salt of 3-isobutyl-1-methyl-6-thioxanthine (M&B 5924), are described. Both these 6-thioxanthines are structurally related to theophylline and pharmacologically they are very similar to that compound, the main differences in their actions being essentially quantitative. They were more potent than choline theophyllinate as bronchodilators on the isolated guinea-pig tracheal ring preparation and as coronary dilators on the dog heart-lung preparation. Choline 6-thiotheophyllinate was about as effective as its oxygen analogue in protecting guinea-pigs against the lethal effects of a bronchoconstrictor aerosol; M&B 5924 was more effective in this respect, but the relative bronchodilator activity was much less than on the isolated preparation. Both thioxanthines were less potent than choline theophyllinate as diuretics. One outstanding qualitative difference in their properties was in their effect on the voluntary motor activity of mice; choline theophyllinate in low doses was stimulant whereas the thioxanthines were either inactive at low doses or sedative at higher doses. In dogs, on the other hand, there were indications that M&B 5924 had a stimulant action. PMID:13684289

  13. Potent heterologous antifungal proteins from cheeseweed (Malva parviflora).

    PubMed

    Wang, X; Bunkers, G J

    2000-12-20

    Two novel antifungal proteins were purified and characterized from cheeseweed (Malva parviflora). Both proteins, designated CW-1 and CW-2, are composed of two different subunits of 5000 and 3000 Da, respectively. These proteins possess very potent antifungal activities, and more interestingly the inhibition is fungicidal instead of fungistatic. At low salt condition, the IC(50) of CW-1 and CW-2 against Fusarium graminearum (Fg) is 2.5 ppm. At high salt condition which diminishes the antifungal activity of many antifungal proteins, both CW-1 and CW-2 still maintain potent activity against Fg with IC(50) of 10 ppm. The two subunits could be separated by gel filtration in the presence of 6 M urea, but their antifungal activity cannot be recovered after the removal of urea. Amino acid sequence analysis indicates that both subunits of CW-1 show homology to 2S albumin, whereas the two subunits of CW-2 have homology to vicilin protein from cotton. To our knowledge, this is the first report of isolation and characterization of heterologous antifungal proteins from any source. PMID:11118343

  14. A potent anticancer agent of shikonin derivative targeting tubulin.

    PubMed

    Baloch, Shahla Karim; Ma, Lin; Xu, Guo-Hua; Bai, Li-Fei; Zhao, Hua; Tang, Cheng-Yi; Pang, Yan-Jun; Yang, Rong-Wu; Wang, Xiao-Ming; Lu, Gui-Hua; Yang, Yong-Hua

    2015-12-01

    In this study, a shikonin ester derivative, compound , was selected to evaluate its anticancer activities and we found that compound exhibited better antitubulin activities against the human HepG2 cell line with an IC50 value of 1.097??M. Furthermore, the inhibition of tubulin polymerization results indicated that compound demonstrated the most potent antitubulin activity (IC50 ?=?13.88), which was compared with shikonin and colchicine as positive controls (IC50 ?=?25.28??M and 22.56??M), respectively. Compound was simulated to have good binding site with tubulin and arrested the cell cycle at G2/M phase, which also induces apoptosis in HepG2 cells, in which P53 and members of Bcl-2 protein family were both involved in the progress of apoptosis revealed by western blot. Confocal microscopy observations revealed compound targeted tubulin and altered its polymerization by interfering with microtubule organization. Based on these results, compound functions as a potent anticancer agent targeting tubulin. Chirality 27:274-280, 2015.. © 2015 Wiley Periodicals, Inc. PMID:25663187

  15. Potent Reversible Inhibition of Myeloperoxidase by Aromatic Hydroxamates*

    PubMed Central

    Forbes, Louisa V.; Sjögren, Tove; Auchère, Françoise; Jenkins, David W.; Thong, Bob; Laughton, David; Hemsley, Paul; Pairaudeau, Garry; Turner, Rufus; Eriksson, Håkan; Unitt, John F.; Kettle, Anthony J.

    2013-01-01

    The neutrophil enzyme myeloperoxidase (MPO) promotes oxidative stress in numerous inflammatory pathologies by producing hypohalous acids. Its inadvertent activity is a prime target for pharmacological control. Previously, salicylhydroxamic acid was reported to be a weak reversible inhibitor of MPO. We aimed to identify related hydroxamates that are good inhibitors of the enzyme. We report on three hydroxamates as the first potent reversible inhibitors of MPO. The chlorination activity of purified MPO was inhibited by 50% by a 5 nm concentration of a trifluoromethyl-substituted aromatic hydroxamate, HX1. The hydroxamates were specific for MPO in neutrophils and more potent toward MPO compared with a broad range of redox enzymes and alternative targets. Surface plasmon resonance measurements showed that the strength of binding of hydroxamates to MPO correlated with the degree of enzyme inhibition. The crystal structure of MPO-HX1 revealed that the inhibitor was bound within the active site cavity above the heme and blocked the substrate channel. HX1 was a mixed-type inhibitor of the halogenation activity of MPO with respect to both hydrogen peroxide and halide. Spectral analyses demonstrated that hydroxamates can act variably as substrates for MPO and convert the enzyme to a nitrosyl ferrous intermediate. This property was unrelated to their ability to inhibit MPO. We propose that aromatic hydroxamates bind tightly to the active site of MPO and prevent it from producing hypohalous acids. This mode of reversible inhibition has potential for blocking the activity of MPO and limiting oxidative stress during inflammation. PMID:24194519

  16. Characterization of BU09059: A Novel Potent Selective ?-Receptor Antagonist

    PubMed Central

    2014-01-01

    Kappa-opioid receptor (?) antagonists are potential therapeutic agents for a range of psychiatric disorders. The feasibility of developing ?-antagonists has been limited by the pharmacodynamic properties of prototypic ?-selective antagonists; that is, they inhibit receptor signaling for weeks after a single administration. To address this issue, novel trans-(3R,4R)-dimethyl-4-(3-hydroxyphenyl) piperidine derivatives, based on JDTic, were designed using soft-drug principles. The aim was to determine if the phenylpiperidine-based series of ?-antagonists was amenable to incorporation of a potentially metabolically labile group, while retaining good affinity and selectivity for the ?-receptor. Opioid receptor binding affinity and selectivity of three novel compounds (BU09057, BU09058, and BU09059) were tested. BU09059, which most closely resembles JDTic, had nanomolar affinity for the ?-receptor, with 15-fold and 616-fold selectivity over ?- and ?-receptors, respectively. In isolated tissues, BU09059 was a potent and selective ?-antagonist (pA2 8.62) compared with BU09057 (pA2 6.87) and BU09058 (pA2 6.76) which were not ?-selective. In vivo, BU09059 (3 and 10 mg/kg) significantly blocked U50,488-induced antinociception and was as potent as, but shorter acting than, the prototypic selective ?-antagonist norBNI. These data show that a new JDTic analogue, BU09059, retains high affinity and selectivity for the ?-receptor and has a shorter duration of ?-antagonist action in vivo. PMID:24410326

  17. Method for forming materials

    DOEpatents

    Tolle, Charles R. (Idaho Falls, ID); Clark, Denis E. (Idaho Falls, ID); Smartt, Herschel B. (Idaho Falls, ID); Miller, Karen S. (Idaho Falls, ID)

    2009-10-06

    A material-forming tool and a method for forming a material are described including a shank portion; a shoulder portion that releasably engages the shank portion; a pin that releasably engages the shoulder portion, wherein the pin defines a passageway; and a source of a material coupled in material flowing relation relative to the pin and wherein the material-forming tool is utilized in methodology that includes providing a first material; providing a second material, and placing the second material into contact with the first material; and locally plastically deforming the first material with the material-forming tool so as mix the first material and second material together to form a resulting material having characteristics different from the respective first and second materials.

  18. Intergroup Contact and Pluralistic Ignorance

    Microsoft Academic Search

    J. Nicole Shelton; Jennifer A. Richeson

    2005-01-01

    The present work examined the relationship between people's own interpretations of why they avoid intergroup contact and their interpretations of why out-groups avoid intergroup contact. Studies 1 and 2 demonstrate that Whites and Blacks would like to have more contact with the out-group but believe the out-group does not want to have contact with them. Studies 3–5 show that Whites

  19. Test Scanning Request Form Please complete one form for each test and key.

    E-print Network

    Pantaleone, Jim

    Test Scanning Request Form Please complete one form for each test and key. This Section: Test Name: Contact Person: Email Regarding This Scan Date Received Time Initials Number of Tests Scored: / / : A.M. P

  20. Contact Probe With Pivoting Tip

    NASA Technical Reports Server (NTRS)

    Amos, Jay M.; Raulerson, David A.

    1991-01-01

    Sensor probe follows curved contours, always keeping sensor in contact with contoured surface. Includes freely pivoting tip, which contains sensor. Spring holds tip in contact with surface being scanned. As user moves probe along surface, force of contact keeps tip oriented along local perpendicular to surface. Slopes of up to 90 degrees from axis of probe accommodated.

  1. Ohmic contacts for laser diodes

    NASA Technical Reports Server (NTRS)

    Ladany, I.; Marinelli, D. P.

    1983-01-01

    Requirements for ohmic contacts to laser diodes are discussed, and properties of Schottky barrier tunneling contacts are reviewed. A procedure is described for measuring contact resistance on fabricated laser material without the need for specially constructed samples and contact configurations. Measurements of contact resistance and estimates of specific contact resistance are given for Ti/Pt/Au contacts to surfaces with three different doping levels. It was found that below a p-type carrier concentration of 1 x 10 to the 19th per cu cm the contact resistance is likely to be too high for good device performance. At higher doping levels, a specific contact resistance as low as 2 x 10 to the -6th ohm sq cm was obtained. Oxide stripe lasers provided with the type of contact discussed in this paper have been operated without failures for periods up to 7 years at a current density at the contact of 6-8 kA/sq cm. It appears therefore that these contacts satisfy the need for low resistance and durability and that, at the same time, they do not cause any obvious material degradation.

  2. Producing thin film photovoltaic modules with high integrity interconnects and dual layer contacts

    SciTech Connect

    Jansen, K.W.; Maley, N.

    2000-06-20

    High performance photovoltaic modules are produced with improved interconnects by a special process. Advantageously, the photovoltaic modules have a dual layer back (rear) contact and a front contact with at least one layer. The front contact and the inner layer of the back contact can comprise a transparent conductive oxide. The outer layer of the back contact can comprise a metal or metal oxide. The front contact can also have a dielectric layer. In one form, the dual layer back contact comprises a zinc oxide inner layer and an aluminum outer layer and the front contact comprises a tin oxide inner layer and a silicon dioxide dielectric outer layer. One or more amorphous silicon-containing thin film semiconductors can be deposited between the front and back contacts. The contacts can be positioned between a substrate and an optional superstrate. During production, the transparent conductive oxide layer of the front contact is scribed by a laser, then the amorphous silicon-containing semiconductors and inner layer of the dual layer back contact are simultaneously scribed and trenched (drilled) by the laser and the trench is subsequently filled with the same metal as the outer layer of the dual layer back contact to provide a superb mechanical and electrical interconnect between the front contact and the outer layer of the dual layer back contact. The outer layer of the dual layer back contact can then be scribed by the laser. For enhanced environmental protection, the photovoltaic modules can be encapsulated.

  3. Producing thin film photovoltaic modules with high integrity interconnects and dual layer contacts

    SciTech Connect

    Jansen, Kai W. (Lawrenceville, NJ); Maley, Nagi (Exton, PA)

    2001-01-01

    High performance photovoltaic modules are produced with improved interconnects by a special process. Advantageously, the photovoltaic modules have a dual layer back (rear) contact and a front contact with at least one layer. The front contact and the inner layer of the back contact can comprise a transparent conductive oxide. The outer layer of the back contact can comprise a metal or metal oxide. The front contact can also have a dielectric layer. In one form, the dual layer back contact comprises a zinc oxide inner layer and an aluminum outer layer and the front contact comprises a tin oxide inner layer and a silicon dioxide dielectric outer layer. One or more amorphous silicon-containing thin film semiconductors can be deposited between the front and back contacts. The contacts can be positioned between a substrate and an optional superstrate. During production, the transparent conductive oxide layer of the front contact is scribed by a laser, then the amorphous silicon-containing semiconductors and inner layer of the dual layer back contact are simultaneously scribed and trenched (drilled) by the laser and the trench is subsequently filled with the same metal as the outer layer of the dual layer back contact to provide a superb mechanical and electrical interconnect between the front contact and the outer layer of the dual layer back contact. The outer layer of the dual layer back contact can then be scribed by the laser. For enhanced environmental protection, the photovoltaic modules can be encapsulated.

  4. Producing thin film photovoltaic modules with high integrity interconnects and dual layer contacts

    SciTech Connect

    Jansen, Kai W. (Lawrenceville, NJ); Maley, Nagi (Exton, PA)

    2000-01-01

    High performance photovoltaic modules are produced with improved interconnects by a special process. Advantageously, the photovoltaic modules have a dual layer back (rear) contact and a front contact with at least one layer. The front contact and the inner layer of the back contact can comprise a transparent conductive oxide. The outer layer of the back contact can comprise a metal or metal oxide. The front contact can also have a dielectric layer. In one form, the dual layer back contact comprises a zinc oxide inner layer and an aluminum outer layer and the front contact comprises a tin oxide inner layer and a silicon dioxide dielectric outer layer. One or more amorphous silicon-containing thin film semiconductors can be deposited between the front and back contacts. The contacts can be positioned between a substrate and an optional superstrate. During production, the transparent conductive oxide layer of the front contact is scribed by a laser, then the amorphous silicon-containing semiconductors and inner layer of the dual layer back contact are simultaneously scribed and trenched (drilled) by the laser and the trench is subsequently filled with the same metal as the outer layer of the dual layer back contact to provide a superb mechanical and electrical interconnect between the front contact and the outer layer of the dual layer back contact. The outer layer of the dual layer back contact can then be scribed by the laser. For enhanced environmental protection, the photovoltaic modules can be encapsulated.

  5. Cell-Cell Transmission Enables HIV-1 to Evade Inhibition by Potent CD4bs Directed Antibodies

    PubMed Central

    Schanz, Merle; Reynell, Lucy; Günthard, Huldrych F.; Rusert, Peter; Trkola, Alexandra

    2012-01-01

    HIV is known to spread efficiently both in a cell-free state and from cell to cell, however the relative importance of the cell-cell transmission mode in natural infection has not yet been resolved. Likewise to what extent cell-cell transmission is vulnerable to inhibition by neutralizing antibodies and entry inhibitors remains to be determined. Here we report on neutralizing antibody activity during cell-cell transmission using specifically tailored experimental strategies which enable unambiguous discrimination between the two transmission routes. We demonstrate that the activity of neutralizing monoclonal antibodies (mAbs) and entry inhibitors during cell-cell transmission varies depending on their mode of action. While gp41 directed agents remain active, CD4 binding site (CD4bs) directed inhibitors, including the potent neutralizing mAb VRC01, dramatically lose potency during cell-cell transmission. This implies that CD4bs mAbs act preferentially through blocking free virus transmission, while still allowing HIV to spread through cell-cell contacts. Thus providing a plausible explanation for how HIV maintains infectivity and rapidly escapes potent and broadly active CD4bs directed antibody responses in vivo. PMID:22496655

  6. Dynamic contact angle analysis of silicone hydrogel contact lenses.

    PubMed

    Read, Michael Leonard; Morgan, Philip Bruce; Kelly, Jeremiah Michael; Maldonado-Codina, Carole

    2011-07-01

    Contact angle measurements are used to infer the clinical wetting characteristics of contact lenses. Such characterization has become more commonplace since the introduction of silicone hydrogel contact lens materials, which have been associated with reduced in vivo wetting due to the inclusion of siloxane-containing components. Using consistent methodology and a single investigator, advancing and receding contact angles were measured for 11 commercially available silicone hydrogel contact lens types with a dynamic captive bubble technique employing customized, fully automated image analysis. Advancing contact angles were found to range between 20° and 72° with the lenses falling into six statistically discrete groupings. Receding contact angles fell within a narrower range, between 17° and 22°, with the lenses segregated into three groups. The relationship between these laboratory measurements and the clinical performance of the lenses requires further investigation. PMID:20219845

  7. Contact position sensor using constant contact force control system

    NASA Technical Reports Server (NTRS)

    Sturdevant, Jay (Inventor)

    1995-01-01

    A force control system (50) and method are provided for controlling a position contact sensor (10) so as to produce a constant controlled contact force therewith. The system (50) includes a contact position sensor (10) which has a contact probe (12) for contacting the surface of a target to be measured and an output signal (V.sub.o) for providing a position indication thereof. An actuator (30) is provided for controllably driving the contact position sensor (10) in response to an actuation control signal (I). A controller (52) receives the position indication signal (V.sub.o) and generates in response thereto the actuation control signal (I) so as to provide a substantially constant selective force (F) exerted by the contact probe (12). The actuation drive signal (I) is generated further in response to substantially linear approximation curves based on predetermined force and position data attained from the sensor (10) and the actuator (30).

  8. New plasma source based on contact ionization

    SciTech Connect

    Schrittwieser, R.; Koslover, R.; Karim, R.; Rynn, N.

    1985-07-01

    A new type of plasma source is presented: A collisionless plasma is formed by producing ions on one end and electrons on the other of a cylindrical vacuum chamber in a solenoidal magnetic field. The ions are produced by contact ionization of potassium on tungsten. The source of electrons is a LaB/sub 6/ plate. In the usual single-ended Q machine the elements rhenium, iridium, and platinum are tested as ionizing metals for potassium and barium.

  9. 21 CFR 800.12 - Contact lens solutions and tablets; tamper-resistant packaging.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Contact lens solutions and tablets; tamper-resistant packaging. 800...800.12 Contact lens solutions and tablets; tamper-resistant packaging. (a...soak, or store contact lenses and salt tablets or other dosage forms to...

  10. 21 CFR 800.12 - Contact lens solutions and tablets; tamper-resistant packaging.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Contact lens solutions and tablets; tamper-resistant packaging. 800...800.12 Contact lens solutions and tablets; tamper-resistant packaging. (a...soak, or store contact lenses and salt tablets or other dosage forms to...

  11. 21 CFR 800.12 - Contact lens solutions and tablets; tamper-resistant packaging.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Contact lens solutions and tablets; tamper-resistant packaging. 800...800.12 Contact lens solutions and tablets; tamper-resistant packaging. (a...soak, or store contact lenses and salt tablets or other dosage forms to...

  12. 21 CFR 800.12 - Contact lens solutions and tablets; tamper-resistant packaging.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Contact lens solutions and tablets; tamper-resistant packaging. 800...800.12 Contact lens solutions and tablets; tamper-resistant packaging. (a...soak, or store contact lenses and salt tablets or other dosage forms to...

  13. 21 CFR 800.12 - Contact lens solutions and tablets; tamper-resistant packaging.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Contact lens solutions and tablets; tamper-resistant packaging. 800...800.12 Contact lens solutions and tablets; tamper-resistant packaging. (a...soak, or store contact lenses and salt tablets or other dosage forms to...

  14. Contact Dermatitis: Diagnosis, Treatment, and Outcome

    MedlinePLUS

    ... A - D Contact dermatitis Diagnosis, treatment, and outcome Contact dermatitis: Diagnosis, treatment, and outcome How dermatologists diagnose contact dermatitis To diagnose this common skin condition, dermatologists: ...

  15. Seal for fluid forming tools

    DOEpatents

    Golovashchenko, Sergey Fedorovich (Beverly Hills, MI); Bonnen, John Joseph Francis (Milford, MI)

    2012-03-20

    An electro-hydraulic forming tool for forming a sheet metal blank in a one-sided die has first and second rigid rings that engage opposite sides of a sheet metal blank. The rigid rings are contained within slots on a die portion and a hydraulic force applicator portion of the forming tool. The seals are either resiliently biased by an elastomeric member or inherently resiliently biased into contact with the blank.

  16. Adhesive Contact Sweeper

    NASA Technical Reports Server (NTRS)

    Patterson, Jonathan D.

    1993-01-01

    Adhesive contact sweeper removes hair and particles vacuum cleaner leaves behind, without stirring up dust. Also cleans loose rugs. Sweeper holds commercially available spools of inverted adhesive tape. Suitable for use in environments in which air kept free of dust; optics laboratories, computer rooms, and areas inhabited by people allergic to dust. For carpets, best used in tandem with vacuum cleaner; first pass with vacuum cleaner removes coarse particles, and second pass with sweeper extracts fine particles. This practice extends useful life of adhesive spools.

  17. TOPIC PRIMARY CONTACT SECONDARY CONTACT(S) Accident Reports Marybeth Wilcox Steve Marley

    E-print Network

    TOPIC PRIMARY CONTACT SECONDARY CONTACT(S) Accident Reports Marybeth Wilcox Steve Marley Agency Temps Christie Gilliland Steve Marley or Marybeth Wilcox ASPIRE - Hiring Procedures - Posting a Position Christie Gilliland Steve Marley or Marybeth Wilcox Candidate Itineraries/Scheduling Christie Gilliland

  18. Amphibian glucagon family peptides: potent metabolic regulators in fish hepatocytes.

    PubMed

    Mommsen, T P; Conlon, J M; Irwin, D M

    2001-06-15

    Peptides analogous to glucagon-like peptide-1 (GLP-1) have been isolated from amphibian pancreas and intestine, and their amino acid sequences and cDNA structures elucidated. Just like their mammalian counterpart, these peptides are potent insulinotropins in mammalian pancreatic cells. We show here that these peptides also exert strong glycogenolytic actions when applied to dispersed fish hepatocytes. We compared the potencies of three synthetic GLP-1s from Xenopus laevis and two native GLP-1s from Bufo marinus in the activation of glycogenolysis in the hepatocytes of a marine rockfish (Sebastes caurinus) and two freshwater catfish (Ameiurus nebulosus and A. melas), and demonstrated their effectiveness in increasing the degree of phosphorylation of glycogen phosphorylase. We also compared the glycogenolytic potency of the peptides with those of human GLP-1 and glucagons from human and B. marinus. Sensitivity to these peptides is species-specific, with the rockfish responding at lower concentrations to GLP-1s and the two catfish reacting better to glucagons. However, the relative potency of the amphibian GLP-1s and glucagons is similar in the three species. Xenopus GLP-1C (xGLP-1C) is consistently more potent than xGLP-1B, while xGLP-1A displays the smallest activation of glycogenolysis. Similarly, Bufo GLP-1(32)-the peptide with the highest amino acid sequence identity to xGLP-1C-always shows a higher potency than Bufo GLP-1(37), which is closely related to xGLP-1B. The relative hierarchy of these glycogenolytic GLP-1s differs from their ranking as insulinotropins in mammalian beta-cells. In the rockfish system, Bufo glucagon-36, a C-terminally extended glucagon, is more potent than the shorter bovine glucagon and Bufo glucagon-29 in the activation of glycogenolysis; when tested in A. nebulosus hepatocytes, bovine and amphibian glucagons are equipotent. Amphibian GLP-1s and glucagons activate glycogenolysis in fish hepatocytes through increased phosphorylation of glycogen phosphorylase, implying involvement of the adenylyl cyclase/protein kinase A system in signal transduction. We conclude that the broad physiological effectiveness of GLP-1 has been retained throughout vertebrate evolution, and that both insulinotropic activity and glycogenolytic actions belong to the repertoire of GLP-1. PMID:11384772

  19. Increased resistance of contact lens related bacterial biofilms to antimicrobial activity of soft contact lens care solutions

    PubMed Central

    Szczotka-Flynn, Loretta B.; Imamura, Yoshifumi; Chandra, Jyotsna; Yu, Changping; Mukherjee, Pranab K.; Pearlman, Eric; Ghannoum, Mahmoud A.

    2014-01-01

    PURPOSE To determine if clinical and reference strains of Pseudomonas aeruginosa, Serratia marcescens, and Staphylococcus aureus form biofilms on silicone hydrogel contact lenses, and ascertain antimicrobial activities of contact lens care solutions. METHODS Clinical and American Type Culture Collection (ATCC) reference strains of Pseudomonas aeruginosa, Serratia marcescens, and Staphylococcus aureus were incubated with lotrafilcon A lenses under conditions that facilitate biofilm formation. Biofilms were quantified by quantitative culturing (colony forming units, CFUs), and gross morphology and architecture were evaluated using scanning electron microscopy (SEM) and confocal microscopy. Susceptibilities of the planktonic and biofilm growth phases of the bacteria to five common multipurpose contact lens care solutions and one hydrogen peroxide care solution were assessed. RESULTS P. aeruginosa, S. marcescens, and S. aureus reference and clinical strains formed biofilms on lotrafilcon A silicone hydrogel contact lenses, as dense networks of cells arranged in multiple layers with visible extracellular matrix. The biofilms were resistant to commonly used biguanide preserved multipurpose care solutions. P. aeruginosa and S. aureus biofilms were susceptible to a hydrogen peroxide and a polyquaternium preserved care solution, whereas S. marcescens biofilm was resistant to a polyquaternium preserved care solution but susceptible to hydrogen peroxide disinfection. In contrast, the planktonic forms were always susceptible. CONCLUSIONS P. aeruginosa, S. marcescens, and S. aureus form biofilms on lotrafilcon A contact lenses, which in contrast to planktonic cells, are resistant to the antimicrobial activity of several soft contact lens care products. PMID:19654521

  20. A Prototype Antifungal Contact Lens

    PubMed Central

    Ciolino, Joseph B.; Hudson, Sarah P.; Mobbs, Ashley N.; Hoare, Todd R.; Iwata, Naomi G.; Fink, Gerald R.

    2011-01-01

    Purpose. To design a contact lens to treat and prevent fungal ocular infections. Methods. Curved contact lenses were created by encapsulating econazole-impregnated poly(lactic-co-glycolic) acid (PLGA) films in poly(hydroxyethyl methacrylate) (pHEMA) by ultraviolet photopolymerization. Release studies were conducted in phosphate-buffered saline at 37°C with continuous shaking. The contact lenses and their release media were tested in an antifungal assay against Candida albicans. Cross sections of the pre- and postrelease contact lenses were characterized by scanning electron microscopy and by Raman spectroscopy. Results. Econazole-eluting contact lenses provided extended antifungal activity against Candida albicans fungi. Fungicidal activity varied in duration and effectiveness depending on the mass of the econazole-PLGA film encapsulated in the contact lens. Conclusions. An econazole-eluting contact lens could be used as a treatment for fungal ocular infections. PMID:21527380

  1. Nonlinear cyclical transport phenomena in copper point contacts

    NASA Astrophysics Data System (ADS)

    Kamarchuk, G. V.; Pospelov, A. P.; Savitskiy, A. V.; Koval, L. V.

    2014-10-01

    The method of recording the current-voltage characteristic was used to study the processes occurring at the surface of a point contact conductance channel. The transport characteristics of the point contact in a liquid medium are studied for the first time. The current states of the conductance channel corresponding to the reversible, transient, and irreversible regimes of charge transport in a point contact are studied and identified. In the irreversible range of bias voltage, the famous cyclical effect of electromechanical switching is observed on the contact, which governs the growth and dissolution of dendritic point contacts of the test sample. The electric resistance of the point-contact structure changes over time, going through stages of increase, decrease, and stabilization. Subsequently, the stages of this process are repeated multiple times, reflecting the cyclical nature of the changes in the physiochemical properties of the test object. The current-voltage characteristic of the point contact has a step structure, due to shell effects. Copper point contact conductance histograms, formed spontaneously in the electric field under the influence of the shell effect, are built using the obtained curves. There is a demonstrated presence of preferred current states for the conductance channel, serving as evidence of the quantum nature of conductance changes in the process of dendritic point contact formation.

  2. Langerhans cells form a reticuloepithelial trap for external contact antigens

    Microsoft Academic Search

    Walter B. Shelley; Lennart Juhlin

    1976-01-01

    THE outermost covering of the body, the epidermis, is a thin epithelial sheath comprising three distinct cell types, keratinocytes, melanocytes and Langerhans cells. The physicochemical and photo-protective role of the first two is well known, but the function of the third is still unknown, over a hundred years since its discovery1. The Langerhans cell was reported earlier as having a

  3. New Instructional Program Application Form Contact Name(s)

    E-print Network

    it compliment or fill a gap in our current programming? Does SFU Recreation have facilities available to offer on current fee structure) SFU Recreation to approve instructor wage (based on current wage schedule) SFU

  4. 77 FR 40692 - 30-Day Notice of Proposed Information Collection: DS-158, Contact Information and Work History...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-10

    ...Collection: DS-158, Contact Information and Work...Information Collection: Contact Information and Work...VO/L/R. Form Number: DS-158...following methods: Email: oira_submission...must include the DS form number, information...FURTHER INFORMATION CONTACT: You may...

  5. 78 FR 66357 - Proposed Changes to FCC Form 499-A, FCC Form 499-Q, and Accompanying Instructions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ...Reporting Worksheet, FCC Form 499-Q (Form 499-Q) and accompanying instructions (Form 499-Q Instructions) to...audio format), send an email to fcc504@fcc.gov or...FOR FURTHER INFORMATION CONTACT: Charles Eberle,...

  6. Allergic Contact Dermatitis

    PubMed Central

    Nelson, Jenny L.

    2010-01-01

    Epicutaneous patch testing is the gold standard method for the diagnosis of allergic contact dermatitis. Despite this knowledge, many clinical dermatologists do not offer patch testing in their offices or offer testing with only a limited number of allergens. Introduced in 1995, the Thin-Layer Rapid Use Epicutaneous Test originally contained 23 allergens and one control. In 2007, five additional allergens were added. This United States Food and Drug Administration-approved patch testing system made patch testing more convenient, and after its introduction, more dermatologists offered patch testing services. However, the number of allergens in the Thin-Layer Rapid Use Epicutaneous Test remains relatively low. Every two years, the North American Contact Dermatitis Group collects and reports the data from patch testing among its members to a standardized series of allergens. In 2005-2006, the Group used a series of 65 allergens. Of the top 30 allergens reported in 2005-2006, 10 were not included in the Thin-Layer Rapid Use Epicutaneous Test. Knowledge of and testing for additional allergens such as these may increase patch testing yield. PMID:20967194

  7. Anti-inflammatory and immune-regulatory mechanisms prevent contact hypersensitivity to Arnica montana L.

    PubMed

    Lass, Christian; Vocanson, Marc; Wagner, Steffen; Schempp, Christoph M; Nicolas, Jean-Francois; Merfort, Irmgard; Martin, Stefan F

    2008-10-01

    Sesquiterpene lactones (SL), secondary plant metabolites from flowerheads of Arnica, exert anti-inflammatory effects mainly by preventing nuclear factor (NF)-kappaB activation because of alkylation of the p65 subunit. Despite its known immunosuppressive action, Arnica has been classified as a plant with strong potency to induce allergic contact dermatitis. Here we examined the dual role of SL as anti-inflammatory compounds and contact allergens in vitro and in vivo. We tested the anti-inflammatory and allergenic potential of SL in the mouse contact hypersensitivity model. We also used dendritic cells to study the activation of NF-kappaB and the secretion of interleukin (IL)-12 in the presence of different doses of SL in vitro. Arnica tinctures and SL potently suppressed NF-kappaB activation and IL-12 production in dendritic cells at high concentrations, but had immunostimulatory effects at low concentrations. Contact hypersensitivity could not be induced in the mouse model, even when Arnica tinctures or SL were applied undiluted to inflamed skin. In contrast, Arnica tinctures suppressed contact hypersensitivity to the strong contact sensitizer trinitrochlorobenzene and activation of dendritic cells. However, contact hypersensitivity to Arnica tincture could be induced in acutely CD4-depleted MHC II knockout mice. These results suggest that induction of contact hypersensitivity by Arnica is prevented by its anti-inflammatory effect and immunosuppression as a result of immune regulation in immunocompetent mice. PMID:18341569

  8. Deorphaning pyrrolopyrazines as potent multi-target antimalarial agents.

    PubMed

    Reker, Daniel; Seet, Michael; Pillong, Max; Koch, Christian P; Schneider, Petra; Witschel, Matthias C; Rottmann, Matthias; Freymond, Céline; Brun, Reto; Schweizer, Bernd; Illarionov, Boris; Bacher, Adelbert; Fischer, Markus; Diederich, François; Schneider, Gisbert

    2014-07-01

    The discovery of pyrrolopyrazines as potent antimalarial agents is presented, with the most effective compounds exhibiting EC50 values in the low nanomolar range against asexual blood stages of Plasmodium falciparum in human red blood cells, and Plasmodium berghei liver schizonts, with negligible HepG2 cytotoxicity. Their potential mode of action is uncovered by predicting macromolecular targets through avant-garde computer modeling. The consensus prediction method suggested a functional resemblance between ligand binding sites in non-homologous target proteins, linking the observed parasite elimination to IspD, an enzyme from the non-mevalonate pathway of isoprenoid biosynthesis, and multi-kinase inhibition. Further computational analysis suggested essential P. falciparum kinases as likely targets of our lead compound. The results obtained validate our methodology for ligand- and structure-based target prediction, expand the bioinformatics toolbox for proteome mining, and provide unique access to deciphering polypharmacological effects of bioactive chemical agents. PMID:24895172

  9. Deoxygedunin, a Natural Product with Potent Neurotrophic Activity in Mice

    PubMed Central

    Jang, Sung-Wuk; Liu, Xia; Chan, Chi Bun; France, Stefan A.; Sayeed, Iqbal; Tang, Wenxue; Lin, Xi; Xiao, Ge; Andero, Raul; Chang, Qiang; Ressler, Kerry J.; Ye, Keqiang

    2010-01-01

    Gedunin, a family of natural products from the Indian neem tree, possess a variety of biological activities. Here we report the discovery of deoxygedunin, which activates the mouse TrkB receptor and its downstream signaling cascades. Deoxygedunin is orally available and activates TrkB in mouse brain in a BDNF-independent way. Strikingly, it prevents the degeneration of vestibular ganglion in BDNF ?/? pups. Moreover, deoxygedunin robustly protects rat neurons from cell death in a TrkB-dependent manner. Further, administration of deoxygedunin into mice displays potent neuroprotective, anti-depressant and learning enhancement effects, all of which are mediated by the TrkB receptor. Hence, deoxygedunin imitates BDNF's biological activities through activating TrkB, providing a powerful therapeutic tool for treatment of various neurological diseases. PMID:20644624

  10. IRAS galaxies versus POTENT mass - Density fields, biasing, and Omega

    NASA Technical Reports Server (NTRS)

    Dekel, Avishai; Bertschinger, Edmund; Yahil, Amos; Strauss, Michael A.; Davis, Marc; Huchra, John P.

    1993-01-01

    A comparison of the galaxy density field extracted from a complete redshift survey of IRAS galaxies brighter than 1.936 Jy with the mass-density field reconstructed by the POTENT procedure from the observed peculiar velocities of 493 objects is presented. A strong correlation is found between the galaxy and mass-density fields; both feature the Great Attractor, part of the Perseus-Pisces supercluster, and the large void between them. Monte Carlo noise simulations show that the data are consistent with the hypotheses that the smoothed fluctuations of galaxy and mass densities at each point are proportional to each other with the 'biasing' factor of IRAS galaxies, b(I), and that the peculiar velocity field is related to the mass-density field as expected according to the gravitational instability theory. Under these hypotheses, the two density fields can be related by specifying b(I) and the cosmological density parameter, Omega.

  11. Discovery of Potent and Reversible Monoacylglycerol Lipase Inhibitors

    PubMed Central

    King, Alvin R.; Dotsey, Emmanuel Y.; Lodola, Alessio; Jung, Kwang Mook; Ghomian, Azar; Qiu, Yan; Fu, Jin; Mor, Marco; Piomelli, Daniele

    2011-01-01

    Summary Monoacylglycerol lipase (MGL) is a serine hydrolase involved in the biological deactivation of the endocannabinoid 2-arachidonoyl-sn-glycerol (2-AG). Previous efforts to design MGL inhibitors have focused on chemical scaffolds that irreversibly block the activity of this enzyme. Here, we describe two naturally occurring terpenoids, pristimerin and euphol, which inhibit MGL activity with high potency (median effective concentration, IC50 = 93 nM and 315 nM, respectively) through a reversible mechanism. Mutational and modeling studies suggest that the two agents occupy a common hydrophobic pocket located within the putative lid domain of MGL, and each reversibly interact with one of two adjacent cysteine residues (Cys201 and Cys208) flanking such pocket. This previously unrecognized regulatory region may offer a novel molecular target for potent and reversible inhibitors of MGL. PMID:19875078

  12. Development of potent inhibitors of the coxsackievirus 3C protease

    SciTech Connect

    Lee, Eui Seung [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Lee, Won Gil [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Yun, Soo-Hyeon [Department of Medicine, Sungkyunkwan University School of Medicine, Cardiac and Vascular Center, Samsung Medical Center, Seoul 135-710 (Korea, Republic of); Rho, Seong Hwan [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Im, Isak [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Yang, Sung Tae [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Sellamuthu, Saravanan [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Lee, Yong Jae [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Kwon, Sun Jae [School of Life Science and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of); Park, Ohkmae K. [School of Life Science and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of); Jeon, Eun-Seok [Department of Medicine, Sungkyunkwan University School of Medicine, Cardiac and Vascular Center, Samsung Medical Center, Seoul 135-710 (Korea, Republic of); Park, Woo Jin [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of)]. E-mail: wjpark@gist.ac.kr; Kim, Yong-Chul [Department of Life Science, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of)]. E-mail: yongchul@gist.ac.kr

    2007-06-22

    Coxsackievirus B3 (CVB3) 3C protease (3CP) plays essential roles in the viral replication cycle, and therefore, provides an attractive therapeutic target for treatment of human diseases caused by CVB3 infection. CVB3 3CP and human rhinovirus (HRV) 3CP have a high degree of amino acid sequence similarity. Comparative modeling of these two 3CPs revealed one prominent distinction; an Asn residue delineating the S2' pocket in HRV 3CP is replaced by a Tyr residue in CVB3 3CP. AG7088, a potent inhibitor of HRV 3CP, was modified by substitution of the ethyl group at the P2' position with various hydrophobic aromatic rings that are predicted to interact preferentially with the Tyr residue in the S2' pocket of CVB3 3CP. The resulting derivatives showed dramatically increased inhibitory activities against CVB3 3CP. In addition, one of the derivatives effectively inhibited the CVB3 proliferation in vitro.

  13. Methadone: a potent inhibitor of rat liver aldehyde oxidase.

    PubMed

    Robertson, I G; Gamage, R S

    1994-02-01

    Several drugs with structural similarities to SKF-525A were tested for their ability to inhibit rat liver aldehyde oxidase using the experimental antitumour agent N-[(2'-dimethylamino)ethyl]acridine-4-carboxamide (AC; NSC 601316; acridine carboxamide) as substrate. The antihistamine D-chlorpheniramine, and the antiarrhythmics disopyramide, procainamide and lignocaine were ineffective in inhibiting this reaction. The antihistamines diphenhydramine, pheniramine, doxylamine, orphenadrine, methapyrilene and pyrilamine, gave IC50 values of 100-500 microM. The narcotic analgesics D-propoxyphene and, in particular, methadone were potent inhibitors of acridine formation with IC50 values of 15.5 and 0.31 microM, respectively. Further analysis indicates mixed non-competitive type inhibition by methadone with inhibition constants (Kis and Kii, respectively) of 0.03 +/- 0.01 (SE) and 0.57 +/- 0.12 microM. PMID:8117328

  14. Cardiac Glycosides from Antiaris toxicaria with Potent Cardiotonic Activity

    PubMed Central

    Shi, Li-Shian; Liao, Yu-Ren; Su, Ming-Jai; Lee, An-Sheng; Kuo, Ping-Chung; Damu, Amooru G.; Kuo, Sheng-Chu; Sun, Han-Dong; Lee, Kuo-Hsiung; Wu, Tian-Shung

    2010-01-01

    An ethanolic extract of Antiaris toxicaria trunk bark showed potent in vitro cardiotonic effect on isolated guinea pig atria. Bioassay-guided fractionation of the extract led to identification of 9 new cardiac glycosides (1–9, named antiarosides A-I), antiarotoxinin A (10), and 18 known compounds. Their structures were established using MS and NMR spectroscopic studies, including homonuclear and heteronuclear correlation experiments. The ability of these cardiotonic compounds to produce positive inotropic action and their safety indexes were examined in comparison with those of ouabain, a classical inhibitor of Na+/K+-ATPase. Malayoside (23) was nearly equipotent and had a similar safety index to ouabain in guinea pig atria. However, the maximal positive inotropic effect and safety index of 23 in papillary muscle were better than those of ouabain. An electrophysiological recording showed that 23 inhibited sodium pump current in a concentration-dependent manner. PMID:20553004

  15. Biosynthesis of the Potent Antimalarial Compound FR900098

    PubMed Central

    Eliot, Andrew C.; Griffin, Benjamin M.; Thomas, Paul M.; Johannes, Tyler W.; Kelleher, Neil L.; Zhao, Huimin; Metcalf, William W.

    2008-01-01

    The antibiotics fosmidomycin and FR900098 are members of a unique class of phosphonic acid natural products that inhibit the nonmevalonate pathway for isoprenoid biosynthesis. Both are potent anti-bacterial and anti-malarial compounds, but despite their efficacy, little is known regarding their biosynthesis. Here we report the identification of the Streptomyces rubellomurinus genes required for the biosynthesis of FR900098. Expression of these genes in Streptomyces lividans results in production of FR900098, demonstrating their role in synthesis of the antibiotic. Analysis of the putative gene products suggests that FR900098 is synthesized by metabolic reactions analogous to portions of the tricarboxylic acid cycle. These data greatly expand our knowledge of phosphonate biosynthesis and enable efforts to overproduce this highly useful therapeutic agent. PMID:18721747

  16. 77 FR 18850 - Notice of Proposed Renewal of Information Collection: Donor Certification Form

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ...Certification Form. DATES: Consideration...DC 20240, or email her at Olivia...Certification Form. FOR FURTHER INFORMATION CONTACT: To request...establish the contact Organization, Email address, City...certification...

  17. Polyoxometalates--potent and selective ecto-nucleotidase inhibitors.

    PubMed

    Lee, Sang-Yong; Fiene, Amelie; Li, Wenjin; Hanck, Theodor; Brylev, Konstantin A; Fedorov, Vladimir E; Lecka, Joanna; Haider, Ali; Pietzsch, Hans-Jürgen; Zimmermann, Herbert; Sévigny, Jean; Kortz, Ulrich; Stephan, Holger; Müller, Christa E

    2015-01-15

    Polyoxometalates (POMs) are inorganic cluster metal complexes that possess versatile biological activities, including antibacterial, anticancer, antidiabetic, and antiviral effects. Their mechanisms of action at the molecular level are largely unknown. However, it has been suggested that the inhibition of several enzyme families (e.g., phosphatases, protein kinases or ecto-nucleotidases) by POMs may contribute to their pharmacological properties. Ecto-nucleotidases are cell membrane-bound or secreted glycoproteins involved in the hydrolysis of extracellular nucleotides thereby regulating purinergic (and pyrimidinergic) signaling. They comprise four distinct families: ecto-nucleoside triphosphate diphosphohydrolases (NTPDases), ecto-nucleotide pyrophosphatases/phosphodiesterases (NPPs), alkaline phosphatases (APs) and ecto-5'-nucleotidase (eN). In the present study, we evaluated the inhibitory potency of a series of polyoxometalates as well as chalcogenide hexarhenium cluster complexes at a broad range of ecto-nucleotidases. [Co4(H2O)2(PW9O34)2](10-) (5, PSB-POM142) was discovered to be the most potent inhibitor of human NTPDase1 described so far (Ki: 3.88 nM). Other investigated POMs selectively inhibited human NPP1, [TiW11CoO40](8-) (4, PSB-POM141, Ki: 1.46 nM) and [NaSb9W21O86](18-) (6, PSB-POM143, Ki: 4.98 nM) representing the most potent and selective human NPP1 inhibitors described to date. [NaP5W30O110](14-) (8, PSB-POM144) strongly inhibited NTPDase1-3 and NPP1 and may therefore be used as a pan-inhibitor to block ATP hydrolysis. The polyoxoanionic compounds displayed a non-competitive mechanism of inhibition of NPPs and eN, but appeared to be competitive inhibitors of TNAP. Future in vivo studies with selected inhibitors identified in the current study are warranted. PMID:25449596

  18. Are genotoxic carcinogens more potent than nongenotoxic carcinogens?

    PubMed Central

    Parodi, S; Malacarne, D; Romano, P; Taningher, M

    1991-01-01

    In this report we have raised the question whether genotoxic carcinogens are more potent than nongenotoxic carcinogens when studied in long-term carcinogenicity assays in rodents. To build a large database of compounds for which both carcinogenicity and genotoxicity had been investigated, we have used a database produced by Gold and co-workers for carcinogenic potency data (975 chemicals) and a database produced by Würgler for genotoxicity data (2834 chemicals). Considering compounds positive or negative in at least three short-term tests and in at least 75% of available tests, we could define 67 genotoxic carcinogens and 46 nongenotoxic carcinogens. Carcinogenic potency of genotoxic carcinogens was about 50 times higher than carcinogenic potency of nongenotoxic carcinogens. Our results are different from the results of Tennant et al.; their database (24 genotoxic carcinogens and 12 nongenotoxic carcinogens compatible with our definition) seems to suggest that there is practically no difference in potency between genotoxic and nongenotoxic carcinogens. The two databases have only four compounds in common and are also different in terms of number of elements for different chemical classes. Nitrosocompounds, nitrogen mustards, hydrazine derivatives, and polycyclic aromatic hydrocarbons are not represented in the database of Tennant. The overall impression from our analysis is that the usefulness of short-term tests of genotoxicity could be significantly better than what has been suggested by the previous work of Tennant et al. because these tests tend to detect, at least for many important chemical classes, the most potent carcinogens. This consideration may not be valid for certain classes of chemicals. PMID:1821372

  19. Novel benzisoxazole derivatives as potent and selective inhibitors of acetylcholinesterase.

    PubMed

    Villalobos, A; Blake, J F; Biggers, C K; Butler, T W; Chapin, D S; Chen, Y L; Ives, J L; Jones, S B; Liston, D R; Nagel, A A

    1994-08-19

    A series of N-benzylpiperidine benzisoxazoles has been developed as potent and selective inhibitors of the enzyme acetylcholinesterase (AChE). The benzisoxazole heterocycle was found to be an appropriate bioisosteric replacement for the benzoyl functionality present in the N-benzylpiperidine class of inhibitors. The title compounds were synthesized by alkylating 3-methyl-1,2-benzisoxazoles with an iodo piperidine derivatives as the key step. Benzisoxazoles 1b-j,o displayed potent inhibition of AChE in vitro with IC50's = 0.8-14 nM. Particularly interesting were N-acetyl and morpholino derivatives 1g (IC50 = 3 nM) and 1j (IC50 = 0.8 nM), respectively, which displayed outstanding selectivity for acetyl-over butyrylcholinesterase, in excess of 3 orders of magnitude. N-Acetyl 1g also displayed a favorable profile in vivo. This analog showed a dose-dependent elevation of total acetylcholine in mouse forebrain after oral administration with an ED50 = 2.4 mg/kg. In addition, 1g was able to reverse amnesia in a mouse passive avoidance model at doses of 3.2 and 5.6 mg/kg with an average reversal of 89.7%. Molecular dynamics simulations were used to study the possible binding modes of N-benzylpiperidine benzisoxazoles to AChE from Torpedo californica. Key structural insights were obtained regarding the potency of this class of inhibitors. Specifically, Asp-72, Trp-84, Trp-279, Phe-288, and Phe-330 are implicated in the binding of these inhibitors. The N-benzylpiperidine benzisoxazoles may be suitable compounds for the palliative treatment of Alzheimer's Disease. PMID:8064800

  20. Teachers Name Contact Number

    E-print Network

    South Australia, University of

    Lakes campus Switch On: Mawson Lakes--Registration Form #12; Lakes on Thursday 19 September 2013, 1.00--3.30pm. Workshops are between 1.00 and 3.00pm, with a free BBQ offered throughout the afternoon. Once completed, please email your form to iteeevents

  1. Close Contact Fluctuations: Time of Contact

    E-print Network

    Daniel R. Bush; Amit K. Chattopadhyay

    2014-12-03

    The letter resolves the long standing debate as to the proper time scale ($$) of the onset of the immunological synapse (IS) bond, the non-covalent chemical bond defining the immune pathways involving T-cells and antigen presenting cells (APC). Results from our model calculations show $$ to be of the order of seconds instead of minutes. Close to the linearly stable regime, we show that in between the two critical spatial thresholds defined by the integrin:ligand pair ($\\Delta_2\\sim$ 40-45 nm) and the T cell receptor (TCR):pMHC bond ($\\Delta_1\\sim$ 14-15 nm), $$ grows monotonically with increasing co-receptor bond length separation $\\delta$ (= $\\Delta_2-\\Delta_1\\sim$ 26-30 nm) while $$ decays with $\\Delta_1$ for fixed $\\Delta_2$. The non-universal $\\delta$-dependent power-law structure of the probability density function (PDF) further explains why only the TCR:pMHC bond is a likely candidate to form a stable synapse.

  2. Wireless Measurement of Contact and Motion Between Contact Surfaces

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Taylor, Bryant D.

    2007-01-01

    This method uses a magnetic-field- response contact sensor that is designed to identify surface contact and motion between contact locations. The sensor has three components: (1) a capacitor-inductor circuit with two sets of electrical contact pads, (2) a capacitor with a set of electrical contact pads, and (3) an inductor with a set of electrical contact pads. A unique feature of this sensor is that it is inherently multifunctional. Information can be derived from analyzing such sensor response attributes as amplitude, frequency, and bandwidth. A change in one attribute can be due to a change in a physical property of a system. A change in another attribute can be due to another physical property, which has no relationship to the first one.

  3. RAM, an RGDS Analog, Exerts Potent Anti-Melanoma Effects In Vitro and In Vivo

    PubMed Central

    Aguzzi, Maria Simona; D'Arcangelo, Daniela; Giampietri, Claudia; Capogrossi, Maurizio C.; Facchiano, Antonio

    2011-01-01

    Peptides containing the RGD sequence are under continuous investigation given their ability to control cell adhesion and apoptosis. Since small peptides are quickly metabolized and degraded in vivo, developing analogs resistant to serum-induced degradation is a challenging task. RGD analogs developed so far are known as molecules mostly inhibiting cell adhesion; this feature may reduce cell proliferation and tumor development but may not induce regression of tumors or metastases already formed. In the current study, carried out in melanoma in vitro and in vivo models, we show that RAM, an RGD-non-peptide Analog-Molecule, strongly inhibits cells adhesion onto plastic, vitronectin, fibronectin, laminin and von Willebrand Factor while it does not inhibit cell adhesion onto collagen IV, similarly to the RGDS template peptide. It also strongly inhibits in vitro cell proliferation, migration and DNA-synthesis, increases melanoma cells apoptosis and reduces survivin expression. All such effects were observed in collagen IV seeded cells, therefore are most likely independent from the anti adhesive properties. Further, RAM is more stable than the template RGDS; in fact it maintains its anti-proliferation and anti-adhesion effects after long serum exposure while RGDS almost completely loses its effects upon serum exposure. In a mouse metastatic melanoma in vivo model, increasing doses of RAM significantly reduce up to about 80% lung metastases development, while comparable doses of RGDS are less potent. In conclusion these data show that RAM is a potent inhibitor of melanoma growth in vitro, strongly reduces melanoma metastases development in vivo and represents a novel candidate for further in vivo investigations in the cancer treatment field. PMID:21984914

  4. Transfer form

    Cancer.gov

    10/02 Transfer Investigational Agent Form This form is to be used for an intra-institutional transfer, one transfer/form. Division of Cancer Prevention National Cancer Institute National Institutes of Health TRANSFER FROM: Investigator transferring agent:

  5. Healthy Contact Lens Wear and Care

    MedlinePLUS Videos and Cool Tools

    ... Address What's this? Submit What's this? Submit Button Water and Contact Lenses Don’t Mix Be Eye ... Infections Eye infections related to contact lens wear... Water & Contact Lenses Keep contact lenses away from all ...

  6. Predictive models for moving contact line flows

    NASA Technical Reports Server (NTRS)

    Rame, Enrique; Garoff, Stephen

    2003-01-01

    Modeling flows with moving contact lines poses the formidable challenge that the usual assumptions of Newtonian fluid and no-slip condition give rise to a well-known singularity. This singularity prevents one from satisfying the contact angle condition to compute the shape of the fluid-fluid interface, a crucial calculation without which design parameters such as the pressure drop needed to move an immiscible 2-fluid system through a solid matrix cannot be evaluated. Some progress has been made for low Capillary number spreading flows. Combining experimental measurements of fluid-fluid interfaces very near the moving contact line with an analytical expression for the interface shape, we can determine a parameter that forms a boundary condition for the macroscopic interface shape when Ca much les than l. This parameter, which plays the role of an "apparent" or macroscopic dynamic contact angle, is shown by the theory to depend on the system geometry through the macroscopic length scale. This theoretically established dependence on geometry allows this parameter to be "transferable" from the geometry of the measurement to any other geometry involving the same material system. Unfortunately this prediction of the theory cannot be tested on Earth.

  7. A single-pixel wireless contact lens display

    NASA Astrophysics Data System (ADS)

    Lingley, A. R.; Ali, M.; Liao, Y.; Mirjalili, R.; Klonner, M.; Sopanen, M.; Suihkonen, S.; Shen, T.; Otis, B. P.; Lipsanen, H.; Parviz, B. A.

    2011-12-01

    We present the design, construction and in vivo rabbit testing of a wirelessly powered contact lens display. The display consists of an antenna, a 500 × 500 µm2 silicon power harvesting and radio integrated circuit, metal interconnects, insulation layers and a 750 × 750 µm2 transparent sapphire chip containing a custom-designed micro-light emitting diode with peak emission at 475 nm, all integrated onto a contact lens. The display can be powered wirelessly from ~1 m in free space and ~2 cm in vivo on a rabbit. The display was tested on live, anesthetized rabbits with no observed adverse effect. In order to extend display capabilities, design and fabrication of micro-Fresnel lenses on a contact lens are presented to move toward a multipixel display that can be worn in the form of a contact lens. Contact lenses with integrated micro-Fresnel lenses were also tested on live rabbits and showed no adverse effect.

  8. Contact mechanics with adhesion: Interfacial separation and contact area

    E-print Network

    C. Yang; B. N. J. Persson; J. Israelachvili; K. Rosenberg

    2008-08-26

    We study the adhesive contact between elastic solids with randomly rough, self affine fractal surfaces. We present molecular dynamics (MD) simulation results for the interfacial stress distribution and the wall-wall separation. We compare the MD results for the relative contact area and the average interfacial separation, with the prediction of the contact mechanics theory of Persson. We find good agreement between theory and the simulation results. We apply the theory to the system studied by Benz et al. involving polymer in contact with polymer, but in this case the adhesion gives only a small modification of the interfacial separation as a function of the squeezing pressure.

  9. ErAs epitaxial Ohmic contacts to InGaAs/InP Uttam Singisetti,1,a

    E-print Network

    Rodwell, Mark J. W.

    ErAs epitaxial Ohmic contacts to InGaAs/InP Uttam Singisetti,1,a Jeramy D. Zimmerman,2 Mark A ErAs semimetal Ohmic contacts onto n-type In0.53Ga0.47As grown on InP. The contacts were formed specific contact resistivities of 1.5 0.4 m2 horizontal specific contact resistivity H, 4.20 m for the Er

  10. Student Data Mart Access Federated Authorization Form

    E-print Network

    Jiang, Huiqiang

    Student Data Mart Access Federated Authorization Form Revised: August 2013 Access to the University's Student Data Mart environment requires signed approval by your supervisor and the Security Contact, and information concerning the data items stored in the Student Data Mart. Contact the University's Technology

  11. Contact dermatitis in blacks.

    PubMed

    Berardesca, E; Maibach, H I

    1988-07-01

    Black skin is characterized by structural and functional differences such as increased stratum corneum cohesion, melanin content, and stratum corneum layers. These differences seem to make black skin difficult for irritants and light to penetrate, thus explaining the common opinion that skin in blacks is harder and develops contact dermatitis less frequently. The paucity of interpretable epidemiologic data and of clinical and experimental studies does not permit confirmation of this hypothesis, and the few data available are controversial. This article describes the main physiologic differences between black and white barrier function and reviews the literature on irritation, sensitization, and transcutaneous penetration. We found that the data are still too incomplete to generalize on the resistance, or lack thereof, of black skin (versus white skin) to chemical irritation, sensitization, and penetration. PMID:3048818

  12. Low contact resistivity of metals on nitrogen-doped cuprous oxide (Cu 2O) thin-films

    E-print Network

    Siah, Sin Cheng

    Forming low-resistivity contacts on cuprous oxide (Cu[subscript 2]O) is an essential step toward demonstrating its suitability as a candidate solar cell material. We measure the contact resistivity of three noble metals ...

  13. 16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...flammable contact adhesives; labeling. 1500...flammable contact adhesives; labeling. ...flammable contact adhesives, also known as contact bonding cements, when...one-half pint of contact adhesive and similar...

  14. 16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...flammable contact adhesives; labeling. 1500...flammable contact adhesives; labeling. ...flammable contact adhesives, also known as contact bonding cements, when...one-half pint of contact adhesive and similar...

  15. 16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...flammable contact adhesives; labeling. 1500...flammable contact adhesives; labeling. ...flammable contact adhesives, also known as contact bonding cements, when...one-half pint of contact adhesive and similar...

  16. 16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...flammable contact adhesives; labeling. 1500...flammable contact adhesives; labeling. ...flammable contact adhesives, also known as contact bonding cements, when...one-half pint of contact adhesive and similar...

  17. 16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...flammable contact adhesives; labeling. 1500...flammable contact adhesives; labeling. ...flammable contact adhesives, also known as contact bonding cements, when...one-half pint of contact adhesive and similar...

  18. Fabrication of optically reflecting ohmic contacts for semiconductor devices

    DOEpatents

    Sopori, B.L.

    1995-07-04

    A method is provided to produce a low-resistivity ohmic contact having high optical reflectivity on one side of a semiconductor device. The contact is formed by coating the semiconductor substrate with a thin metal film on the back reflecting side and then optically processing the wafer by illuminating it with electromagnetic radiation of a predetermined wavelength and energy level through the front side of the wafer for a predetermined period of time. This method produces a thin epitaxial alloy layer between the semiconductor substrate and the metal layer when a crystalline substrate is used. The alloy layer provides both a low-resistivity ohmic contact and high optical reflectance. 5 figs.

  19. On the classification of the almost contact metric manifolds

    E-print Network

    Alexiev, Valentin A

    2011-01-01

    The vector space of the tensors $\\mathcal F$ of type (0,3) having the same symmetries as the covariant derivative of the fundamental form of an almost contact metric manifold is considered. A scheme of decomposition of $\\mathcal F$ into orthogonal components which are invariant under the action of $U(n)\\times 1$ is given. Using this decomposition there are found 12 natural basic classes of almost contact metric manifolds. The classes of cosymplectic, $\\alpha$-Sasakian, $\\alpha$-Kenmotsu, etc. manifolds fit nicely to these considerations. On the other hand, many new interesting classes of almost contact metric manifolds arise.

  20. Superconductor-normal-superconductor with distributed Sharvin point contacts

    DOEpatents

    Holcomb, Matthew J. (San Mateo County, CA); Little, William A. (Santa Clara County, CA)

    1994-01-01

    A non-linear superconducting junction device comprising a layer of high transient temperature superconducting material which is superconducting at an operating temperature, a layer of metal in contact with the layer of high temperature superconducting material and which remains non-superconducting at the operating temperature, and a metal material which is superconducting at the operating temperature and which forms distributed Sharvin point contacts with the metal layer.

  1. A potent ruthenium(II) antitumor complex bearing a lipophilic levonorgestrel group.

    PubMed

    Ruiz, José; Rodríguez, Venancio; Cutillas, Natalia; Espinosa, Arturo; Hannon, Michael J

    2011-09-19

    The novel steroidal conjugate 17-?-[2-phenylpyridyl-4-ethynyl]-19-nortestosterone (LEV-ppy) (1) and the steroid-C,N-chelate ruthenium(II) conjugate [Ru(?(6)-p-cymene)(LEV-ppy)Cl] (2) have been prepared. At 48 h incubation time, complex 2 is more active than cisplatin (about 8-fold) in T47D (breast cancer) and also shows an improved efficiency when compared to its nonsteroidal analogue [Ru(?(6)-p-cymene)(ppy)Cl] (ppy = phenylpyridine) (3) in the same cell line. The act of conjugating a levonorgestrel group to a ruthenium(II) complex resulted in synergistic effects between the metallic center and the steroidal ligand, creating highly potent ruthenium(II) complexes from the inactive components. The interaction of 2 with DNA was followed by electrophoretic mobility. Theoretical density functional theory calculations on complex 2 show the metal center far away from the lipophilic steroidal moiety and a labile Ru-Cl bond that allows easy replacement of Cl by N-nucleophiles such as 9-EtG, thus forming a stronger Ru-N bond. We also found a minimum energy location for the chloride counteranion (4(+)·Cl(-)) inside the pseudocavity formed by the ? side of the steroid moiety, the phenylpyridine chelating subsystem, and the guanine ligand, i.e., a host-guest species with a rich variety of nonbonding interactions that include nonclassical C-H···anion bonds, as supported by electrospray ionization mass spectra. PMID:21830785

  2. A B220+ CD117+ CD19- hematopoietic progenitor with potent lymphoid and myeloid developmental potential.

    PubMed

    Balciunaite, Gina; Ceredig, Rod; Massa, Steffen; Rolink, Antonius G

    2005-07-01

    In this report, we identify in the bone marrow (BM) of normal mice a subpopulation of B220+ CD117+ CD19- NK1.1- cells with potent lymphoid and myeloid developmental potential. These cells represent 0.1-0.2% of nucleated BM cells. By limiting dilution analysis in the presence of the appropriate combination of stromal cells and cytokines, 1 in 5-10 sorted cells formed B cells, 1 in 10-15 formed T cells and 1 in 5-10 generated macrophages. When cultured on a mixture of OP9 stroma and OP9 stromal cells expressing the Notch ligand Delta-like-1, single cells generated both T and B cells. Following intravenous infusion, freshly sorted cells transiently reconstituted both the T and B cell progenitor compartments, generating cohorts of mature T and B lymphocytes. The relationship between B220+ CD117+ CD19- NK1.1- cells of wild-type mice and other multi-lineage BM progenitors is discussed. PMID:15971276

  3. Interbilayer-crosslinked multilamellar vesicles as synthetic vaccines for potent humoral and cellular immune responses

    NASA Astrophysics Data System (ADS)

    Moon, James J.; Suh, Heikyung; Bershteyn, Anna; Stephan, Matthias T.; Liu, Haipeng; Huang, Bonnie; Sohail, Mashaal; Luo, Samantha; Ho Um, Soong; Khant, Htet; Goodwin, Jessica T.; Ramos, Jenelyn; Chiu, Wah; Irvine, Darrell J.

    2011-03-01

    Vaccines based on recombinant proteins avoid the toxicity and antivector immunity associated with live vaccine (for example, viral) vectors, but their immunogenicity is poor, particularly for CD8+ T-cell responses. Synthetic particles carrying antigens and adjuvant molecules have been developed to enhance subunit vaccines, but in general these materials have failed to elicit CD8+ T-cell responses comparable to those for live vectors in preclinical animal models. Here, we describe interbilayer-crosslinked multilamellar vesicles formed by crosslinking headgroups of adjacent lipid bilayers within multilamellar vesicles. Interbilayer-crosslinked vesicles stably entrapped protein antigens in the vesicle core and lipid-based immunostimulatory molecules in the vesicle walls under extracellular conditions, but exhibited rapid release in the presence of endolysosomal lipases. We found that these antigen/adjuvant-carrying vesicles form an extremely potent whole-protein vaccine, eliciting endogenous T-cell and antibody responses comparable to those for the strongest vaccine vectors. These materials should enable a range of subunit vaccines and provide new possibilities for therapeutic protein delivery.

  4. Interbilayer-Crosslinked Multilamellar Vesicles as Synthetic Vaccines for Potent Humoral and Cellular Immune Responses

    PubMed Central

    Moon, James J.; Suh, Heikyung; Bershteyn, Anna; Stephan, Matthias T.; Liu, Haipeng; Huang, Bonnie; Sohail, Mashaal; Luo, Samantha; Um, Soong Ho; Khant, Htet; Goodwin, Jessica T.; Ramos, Jenelyn; Chiu, Wah; Irvine, Darrell J.

    2011-01-01

    Vaccines based on recombinant proteins avoid toxicity and anti-vector immunity associated with live vaccine (e.g., viral) vectors, but their immunogenicity is poor, particularly for CD8+ T-cell (CD8T) responses. Synthetic particles carrying antigens and adjuvant molecules have been developed to enhance subunit vaccines, but in general these materials have failed to elicit CD8T responses comparable to live vectors in preclinical animal models. Here, we describe interbilayer-crosslinked multilamellar vesicles (ICMVs) formed by crosslinking headgroups of adjacent lipid bilayers within multilamellar vesicles. ICMVs stably entrapped protein antigens in the vesicle core and lipid-based immunostimulatory molecules in the vesicle walls under extracellular conditions, but exhibited rapid release in the presence of endolysosomal lipases. We found that these antigen/adjuvant-carrying ICMVs form an extremely potent whole-protein vaccine, eliciting endogenous T-cell and antibody responses comparable to the strongest vaccine vectors. These materials should enable a range of subunit vaccines and provide new possibilities for protein therapeutic delivery. PMID:21336265

  5. Lamellarin D: a novel potent inhibitor of topoisomerase I.

    PubMed

    Facompré, Michaël; Tardy, Christelle; Bal-Mahieu, Christine; Colson, Pierre; Perez, Carlos; Manzanares, Ignacio; Cuevas, Carmen; Bailly, Christian

    2003-11-01

    We report the identification and characterization of a novel potent inhibitor of DNA topoisomerase I: lamellarin D (LAM-D), initially isolated from a marine mollusk, Lamellaria sp., and subsequently identified from various ascidians. This alkaloid, which displays potent cytotoxic activities against multidrug-resistant tumor cell lines and is highly cytotoxic to prostate cancer cells, bears a 6H-[1]benzopyrano[4',3':4,5]pyrrolo[2,1-a]isoquinolin-one pentacyclic planar chromophore, whereas its synthetic 5,6-dehydro analogue, LAM-501, has a significantly tilted structure. DNA binding measurements by absorbance, fluorescence, and electric linear dichroism spectroscopy show that LAM-D is a weak DNA binder that intercalates between bp of the double helix. In contrast, the nonplanar analogue LAM-501 did not bind to DNA and failed to inhibit topoisomerase I. DNA intercalation may be required for the stabilization of topoisomerase I-DNA complexes by LAM-D. In the DNA relaxation assay, LAM-D strongly promoted the conversion of supercoiled DNA into nicked DNA in the presence of topoisomerase I. The marine product was approximately 5 times less efficient than camptothecin (CPT) at stabilizing topoisomerase I-DNA complexes, but interestingly, the two drugs exhibited slightly distinct sequence specificity profiles. Topoisomerase I-mediated DNA cleavage in the presence of LAM-D occurred at some sites common to CPT, but a few specific sites identified with CPT but not with LAM-D or conversely unique sites cleaved by LAM-D but not by CPT were detected. The distinct specificity profiles suggest that LAM-D and CPT interact differently with the topoisomerase I-DNA interface. A molecular modeling analysis provided structural information on the orientation of LAM-D within the topoisomerase I-DNA covalent complex. The marine alkaloid did not induce DNA cleavage by topoisomerase II. Immunoblotting experiments revealed that endogenous topoisomerase I was efficiently trapped on DNA by LAM-D in P388 and CEM leukemia cells. P388/CPT5 and CEM/C2 cell lines, both resistant to CPT and expressing a mutated top1 gene, were cross-resistant to LAM-D. Collectively, the results identify LAM-D as a novel lead candidate for the development of topoisomerase I-targeted antitumor agents. PMID:14612538

  6. Discovery of GW870086: a potent anti-inflammatory steroid with a unique pharmacological profile

    PubMed Central

    Uings, I J; Needham, D; Matthews, J; Haase, M; Austin, R; Angell, D; Leavens, K; Holt, J; Biggadike, K; Farrow, S N

    2013-01-01

    Background and Purpose Glucocorticoids are highly effective therapies for a range of inflammatory diseases. Advances in the understanding of the diverse molecular mechanisms underpinning glucocorticoid action suggest that anti-inflammatory molecules with reduced side effect liabilities can be discovered. Here we set out to explore whether modification of the 17? position of the steroid nucleus could generate molecules with a unique pharmacological profile and to determine whether such molecules would retain anti-inflammatory activity. Experimental Approach The pharmacological properties of GW870086 were compared with fluticasone propionate (FP) using a range of cellular and in vivo model systems, including extensive gene expression profiling. Key Results GW870086 repressed inflammatory cytokine release from lung epithelial cells in a similar manner to FP but antagonized the effect of dexamethasone on MMTV-driven reporter gene transactivation. GW870086 had a strong effect on the expression of some glucocorticoid-regulated genes (such as PTGS2), while having minimal impact on the expression of other known target genes (such as SGK). GW870086 retained the ability to strengthen tight junctions in epithelial cell culture but, unlike FP, was unable to protect the culture from elastase-mediated damage. In murine models of irritant-induced contact dermatitis and ovalbumin-induced allergic inflammation, GW870086 showed comparable anti-inflammatory efficacy to FP. Conclusion and Implications GW870086 is a potent anti-inflammatory compound with a unique ability to regulate only a subset of those genes that are normally affected by classical glucocorticoids. It has the potential to become a new topical steroid with a different safety profile to existing therapies. PMID:23639214

  7. Atomic Contacts characterized by Force and Current

    NASA Astrophysics Data System (ADS)

    Hagedorn, Till

    2011-12-01

    Contacts between atoms present the reduction of an electronic system to the smallest scale accessible at the present. Field ion microscopy (FIM) and simultaneous scanning tunneling microscopy (STM) and atomic force microscopy (AFM) were used to characterize atomic contacts between a tungsten (W(111)) STM-tip and a gold (Au(111)) sample. The STM-tip was imaged with atomic resolution using FIM and reconstructed in a three dimensional ball model. Force and current were measured simultaneously while the tip approached an atomically flat Au(111) sample to form a contact. A detailed description of the tip production and characterization using an etching setup that was developed for this thesis is introduced. These tips are characterized by field ion microscopy (FIM). The adaptation of a well known three dimensional ball model reconstruction to the tungsten bcc(111) crystal is described and utilized to reconstruct FIM micrographs of W(111) STM-tips. Using several of such tips, the long-range forces of the tip-sample system were analyzed using recent theoretical models, concluding that van der Waals and electrostatic force contributions were negligible for tips with a radius smaller than rtip = 15 nm within the precision of the FIM-STM/AFM system that was employed for the experiments. Force and current data for different structural modifications of the W(111)-Au(111) SPM tunneling junction are presented and discussed. Findings include that the W-Au junction in geometries which were examined in this thesis do not exhibit the conductive properties of a one-atom contact. A comparison of different theoretical approaches that treat the correlation of force and current in a STM type tunneling junction is presented and the results of this thesis support a F2? It proportionality for a three-atom tungsten tip contacting an atomically flat Au(111) sample.

  8. UVM Alana Gear MEDICAL HISTORY FORM

    E-print Network

    Hayden, Nancy J.

    UVM Alana Gear MEDICAL HISTORY FORM Name:_________________________________ E - Mail # : ___________________ Emergency Contact #2 : _________________________ Phone # : __________________ Physician's Name. Please explain in detail the reaction you have and the last time you had a reaction. 5. Please list any

  9. Graphdiyne-metal contacts and graphdiyne transistors

    NASA Astrophysics Data System (ADS)

    Pan, Yuanyuan; Wang, Yangyang; Wang, Lu; Zhong, Hongxia; Quhe, Ruge; Ni, Zeyuan; Ye, Meng; Mei, Wai-Ning; Shi, Junjie; Guo, Wanlin; Yang, Jinbo; Lu, Jing

    2015-01-01

    Graphdiyne was prepared on a metal surface, and the preparation of devices using it inevitably involves its contact with metals. Using density functional theory with dispersion correction, we systematically studied, for the first time, the interfacial properties of graphdiyne that is in contact with a series of metals (Al, Ag, Cu, Au, Ir, Pt, Ni, and Pd). Graphdiyne forms an n-type Ohmic or quasi-Ohmic contact with Al, Ag, and Cu, while it forms a Schottky contact with Pd, Au, Pt, Ni, and Ir (at the source/drain-channel interface), with high Schottky barrier heights of 0.21, 0.46 (n-type), 0.30, 0.41, and 0.46 (p-type) eV, respectively. A graphdiyne field effect transistor (FET) with Al electrodes was simulated using quantum transport calculations. This device exhibits an on-off ratio up to 104 and a very large on-state current of 1.3 × 104 mA mm-1 in a 10 nm channel length. Thus, a new prospect has opened up for graphdiyne in high performance nanoscale devices.Graphdiyne was prepared on a metal surface, and the preparation of devices using it inevitably involves its contact with metals. Using density functional theory with dispersion correction, we systematically studied, for the first time, the interfacial properties of graphdiyne that is in contact with a series of metals (Al, Ag, Cu, Au, Ir, Pt, Ni, and Pd). Graphdiyne forms an n-type Ohmic or quasi-Ohmic contact with Al, Ag, and Cu, while it forms a Schottky contact with Pd, Au, Pt, Ni, and Ir (at the source/drain-channel interface), with high Schottky barrier heights of 0.21, 0.46 (n-type), 0.30, 0.41, and 0.46 (p-type) eV, respectively. A graphdiyne field effect transistor (FET) with Al electrodes was simulated using quantum transport calculations. This device exhibits an on-off ratio up to 104 and a very large on-state current of 1.3 × 104 mA mm-1 in a 10 nm channel length. Thus, a new prospect has opened up for graphdiyne in high performance nanoscale devices. Electronic supplementary information (ESI) available: (1) Band structure of pure graphdiyne and graphdiyne adsorbed on the surface of Au in three types of configurations, (2) the comparison of the optimized structure of the systems with a Ni surface adjusted to graphdiyne and graphdiyne adjusted to the Ni surface, (3) the comparison of the band structure of graphdiyne and the transmission spectra of a 6 nm-channel-length graphdiyne FET calculated by DFT and SE methods. See DOI: 10.1039/c4nr06541g

  10. Bilayer Graphene Lateral Contacts for DNA Sequencing

    E-print Network

    He, Yuhui; Scheicher, Ralph H; Taniguchi, Masateru; Kawai, Tomoji

    2012-01-01

    Translocation of DNA through a nanopore with embedded electrodes is at the centre of new rapid inexpensive sequencing methods which allow distinguishing the four nucleobases by their different electronic structure. However, the subnanometer separation between nucleotides in DNA requires ultra-sharp probes. Here, we propose a device architecture consisting of a nanopore formed in bilayer graphene, with the two layers acting as separate electrical contacts. The 0.34 nm interlayer distance of graphene is ideally suited for electrical coupling to a single nucleobase, avoiding the difficulty of fabricating probes with subnanometer precision. The top and bottom graphene electrodes contact the target molecule from the same lateral side, removing the orders-of-magnitude tunneling current variations between smaller pyrimidine bases and larger purine bases. We demonstrate that incorporating techniques for molecular manipulation enables the proposed device to sequence single-stranded DNA and that it offers even the pros...

  11. 'Contact' in Space Leads to New Lenses

    NASA Technical Reports Server (NTRS)

    2004-01-01

    While gravity has its advantages in keeping us balanced and grounded here on Earth, scientists often find that they are at a disadvantage when trying to conduct research under its powerful, pulling influence. In these instances, the scientists prefer performing their studies in the weightless atmosphere of microgravity, where gravity is greatly reduced and solids, liquids, and gases behave differently. In 1993, Paragon Vision Sciences, Inc., of Mesa, Arizona, participated in a research project with NASA's Langley Research Center to perfect a process for developing contact lenses. The project called for three experiments that would fly onboard the Space Shuttle over the course of three separate missions, from 1993 to 1996. By unleashing contact lens materials to the microgravity settings of space, scientists from NASA and Paragon hoped to better understand how polymers - large molecules that make up plastics - are formed.

  12. Role of membrane contact sites in protein import into mitochondria.

    PubMed

    Horvath, Susanne E; Rampelt, Heike; Oeljeklaus, Silke; Warscheid, Bettina; van der Laan, Martin; Pfanner, Nikolaus

    2015-03-01

    Mitochondria import more than 1,000 different proteins from the cytosol. The proteins are synthesized as precursors on cytosolic ribosomes and are translocated by protein transport machineries of the mitochondrial membranes. Five main pathways for protein import into mitochondria have been identified. Most pathways use the translocase of the outer mitochondrial membrane (TOM) as the entry gate into mitochondria. Depending on specific signals contained in the precursors, the proteins are subsequently transferred to different intramitochondrial translocases. In this article, we discuss the connection between protein import and mitochondrial membrane architecture. Mitochondria possess two membranes. It is a long-standing question how contact sites between outer and inner membranes are formed and which role the contact sites play in the translocation of precursor proteins. A major translocation contact site is formed between the TOM complex and the presequence translocase of the inner membrane (TIM23 complex), promoting transfer of presequence-carrying preproteins to the mitochondrial inner membrane and matrix. Recent findings led to the identification of contact sites that involve the mitochondrial contact site and cristae organizing system (MICOS) of the inner membrane. MICOS plays a dual role. It is crucial for maintaining the inner membrane cristae architecture and forms contacts sites to the outer membrane that promote translocation of precursor proteins into the intermembrane space and outer membrane of mitochondria. The view is emerging that the mitochondrial protein translocases do not function as independent units, but are embedded in a network of interactions with machineries that control mitochondrial activity and architecture. PMID:25514890

  13. 77 FR 19670 - Agency Information Collection Activities; Proposed Collection; Comment Request; Food Contact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    ...require the submission of Form FDA 3479 (``Notification for a Food Contact Substance Formulation...notifications for uses of food contact substances. \\4\\ Notifications...require the submission of Form FDA 3480. \\8\\ These...format via the ESG; email, if appropriate;...

  14. A theoretical model for acoustic emission sensing process in contact/near-contact interfaces of magnetic recording system

    NASA Astrophysics Data System (ADS)

    Sheng, Gang; Liu, Bo; Hua, Wei; Chen, Qisuo

    1999-04-01

    This article presents a theoretical model to account for acoustic emission (AE) sensor dynamics in the measurement of head-disk contact/near-contact in magnetic recording system. The AE transducing system is modeled as a linear dynamic system excited by deterministic and random input. The impulse response method and power flow method are applied, respectively, to characterize the system responses. An analytical model is established to describe the dependence of AE output on system transfer functions, filter parameters, excitation forms, contact force, velocity, topographic and mechanical parameters, as well as lubricant thickness.

  15. Molecular dynamics study of contact mechanics: contact area and interfacial separation from small to full contact

    NASA Astrophysics Data System (ADS)

    Yang, Chunyan; Persson, Bo

    2008-03-01

    We report a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. We study the contact area and the interfacial separation from small contact (low load) to full contact (high load). For small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load [1-4]. For high load the contact area approaches to the nominal contact area (i.e., complete contact), and the interfacial separation approaches to zero. The present results may be very important for soft solids, e.g., rubber, or for very smooth surfaces, where complete contact can be reached at moderate high loads without plastic deformation of the solids. References: [1] C. Yang and B.N.J. Persson, arXiv:0710.0276, (to appear in Phys. Rev. Lett.) [2] B.N.J. Persson, Phys. Rev. Lett. 99, 125502 (2007) [3] L. Pei, S. Hyun, J.F. Molinari and M.O. Robbins, J. Mech. Phys. Sol. 53, 2385 (2005) [4] M. Benz, K.J. Rosenberg, E.J. Kramer and J.N. Israelachvili, J. Phy. Chem. B.110, 11884 (2006)

  16. Trifluoromethoxyl Substituted Phenylethylene Diamines as High Affinity Receptor Ligands with Potent Anti-Cocaine Actions

    E-print Network

    with Potent Anti-Cocaine Actions Trudy A. Smith, Xiaowen Yang, Huifang Wu, Buddy Pouw, Rae R. Matsumoto and with anti-cocaine actions that involve antagonism of 1 receptors. In order to increase the potency receptor affinity and represent the most potent anti-cocaine phenylethylene diamines yet described

  17. Discovery of two new classes of potent monoamine oxidase-B inhibitors by tricky chemistry.

    PubMed

    Cagide, F; Silva, T; Reis, J; Gaspar, A; Borges, F; Gomes, L R; Low, J N

    2015-02-18

    The discovery of potent and selective monoamine oxidase-B inhibitors for the management of neurodegenerative diseases such as Alzheimer's and Parkinson's diseases is still a challenging endeavor. Herein, we report the discovery of two new classes of potent and selective MAO-B inhibitors based on chromane-2,4-dione and chromone-3-carboxamide scaffolds. PMID:25579652

  18. A Potent Human Immunodeficiency Virus Type 1 Protease Inhibitor, UIC-94003 (TMC-126), and Selection of a Novel (A28S) Mutation in the Protease Active Site

    PubMed Central

    Yoshimura, Kazuhisa; Kato, Ryohei; Kavlick, Mark F.; Nguyen, Aline; Maroun, Victor; Maeda, Kenji; Hussain, Khaja A.; Ghosh, Arun K.; Gulnik, Sergei V.; Erickson, John W.; Mitsuya, Hiroaki

    2002-01-01

    We identified UIC-94003, a nonpeptidic human immunodeficiency virus (HIV) protease inhibitor (PI), containing 3(R),3a(S),6a(R)-bis-tetrahydrofuranyl urethane (bis-THF) and a sulfonamide isostere, which is extremely potent against a wide spectrum of HIV (50% inhibitory concentration, 0.0003 to 0.0005 ?M). UIC-94003 was also potent against multi-PI-resistant HIV-1 strains isolated from patients who had no response to any existing antiviral regimens after having received a variety of antiviral agents (50% inhibitory concentration, 0.0005 to 0.0055 ?M). Upon selection of HIV-1 in the presence of UIC-94003, mutants carrying a novel active-site mutation, A28S, in the presence of L10F, M46I, I50V, A71V, and N88D appeared. Modeling analysis revealed that the close contact of UIC-94003 with the main chains of the protease active-site amino acids (Asp29 and Asp30) differed from that of other PIs and may be important for its potency and wide-spectrum activity against a variety of drug-resistant HIV-1 variants. Thus, introduction of inhibitor interactions with the main chains of key amino acids and seeking a unique inhibitor-enzyme contact profile should provide a framework for developing novel PIs for treating patients harboring multi-PI-resistant HIV-1. PMID:11773409

  19. Merlin Is a Potent Inhibitor of Glioma Growth

    PubMed Central

    Lau, Ying-Ka Ingar; Murray, Lucas B.; Houshmandi, Sean S.; Xu, Yin; Gutmann, David H.; Yu, Qin

    2009-01-01

    Neurofibromatosis 2 (NF2) is an inherited cancer syndrome in which affected individuals develop nervous system tumors, including schwannomas, meningiomas, and ependymomas. The NF2 protein merlin (or schwannomin) is a member of the Band 4.1 superfamily of proteins, which serve as linkers between transmembrane proteins and the actin cytoskeleton. In addition to mutational inactivation of the NF2 gene in NF2-associated tumors, mutations and loss of merlin expression have also been reported in other types of cancers. In the present study, we show that merlin expression is dramatically reduced in human malignant gliomas and that reexpression of functional merlin dramatically inhibits both subcutaneous and intracranial growth of human glioma cells in mice. We further show that merlin reexpression inhibits glioma cell proliferation and promotes apoptosis in vivo. Using microarray analysis, we identify altered expression of specific molecules that play key roles in cell proliferation, survival, and motility. These merlin-induced changes of gene expression were confirmed by real-time quantitative PCR, Western blotting, and functional assays. These results indicate that reexpression of merlin correlates with activation of mammalian sterile 20-like 1/2–large tumor suppressor 2 signaling pathway and inhibition of canonical and noncanonical Wnt signals. Collectively, our results show that merlin is a potent inhibitor of high-grade human glioma. PMID:18632626

  20. Plants from Brazilian Cerrado with Potent Tyrosinase Inhibitory Activity

    PubMed Central

    Souza, Paula Monteiro; Elias, Silvia Taveira; Simeoni, Luiz Alberto; de Paula, José Elias; Gomes, Sueli Maria; Guerra, Eliete Neves Silva; Fonseca, Yris Maria; Silva, Elton Clementino; Silveira, Dâmaris; Magalhães, Pérola Oliveira

    2012-01-01

    The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05) tyrosinase inhibitory activity exhibiting the IC50 value of 11.88 µg/mL, compared to kojic acid (IC50 value of 13.14 µg/mL). Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC50 value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations. PMID:23173036

  1. Plants from Brazilian Cerrado with potent tyrosinase inhibitory activity.

    PubMed

    Souza, Paula Monteiro; Elias, Silvia Taveira; Simeoni, Luiz Alberto; de Paula, José Elias; Gomes, Sueli Maria; Guerra, Eliete Neves Silva; Fonseca, Yris Maria; Silva, Elton Clementino; Silveira, Dâmaris; Magalhães, Pérola Oliveira

    2012-01-01

    The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05) tyrosinase inhibitory activity exhibiting the IC?? value of 11.88 µg/mL, compared to kojic acid (IC?? value of 13.14 µg/mL). Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC?? value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations. PMID:23173036

  2. Discovery of highly potent TNF? inhibitors using virtual screen.

    PubMed

    Shen, Qi; Chen, Jing; Wang, Qian; Deng, Xiaobing; Liu, Ying; Lai, Luhua

    2014-10-01

    Tumor necrosis factor-? (TNF?) is a validated therapeutic target for various autoimmune disorders such as rheumatoid arthritis and asthma. All TNF? inhibitors currently on the market are biologics, making the development of small molecule alternatives in urgent need. However, only a few successful cases of direct TNF? antagonization in vitro have been reported. Here, we present the identification of several small molecule candidates able to effectively reduce TNF? activity in vitro and in cell assays. Virtual screen targeting TNF? dimer was performed on the SPECS database and 101 compounds were selected for experimental testing. Two compounds, 1 and 2, displayed considerable inhibitory activity. Follow-up structure-activity relationship analysis of compound 1 identified 3 molecules with low micromolar cell-level inhibitory activity. Compound 11 showed an IC50 value of 14 ?M, making it among the most potent TNF? small molecule inhibitors reported. These compounds provide new scaffolds for future development of small molecule drugs against TNF?. PMID:25078315

  3. Identification of three potent hydroxyproline O-galactosyltransferases in Arabidopsis.

    PubMed

    Ogawa-Ohnishi, Mari; Matsubayashi, Yoshikatsu

    2015-03-01

    Arabinogalactan proteins (AGPs) are plant-specific extracellular glycoproteins implicated in a variety of processes during growth and development. AGP biosynthesis involves O-galactosylation of hydroxyproline (Hyp) residues followed by a stepwise elongation of the complex sugar chains. However, functionally dominant Hyp O-galactosyltransferases, such that their disruption produces phenocopies of AGP-deficient mutants, remain to be identified. Here, we purified and identified three potent Hyp O-galactosyltransferases, HPGT1, HPGT2 and HPGT3, from Arabidopsis microsomal fractions. Loss-of-function analysis indicated that approximately 90% of the endogenous Hyp O-galactosylation activity is attributable to these three enzymes. AGP14 expressed in the triple mutant migrated much faster on SDS-PAGE than when expressed in wild-type, confirming a considerable decrease in levels of glycosylation of AGPs in the mutant. Loss-of-function mutant plants exhibited a pleiotropic phenotype of longer lateral roots, longer root hairs, radial expansion of the cells in the root tip, small leaves, shorter inflorescence stems, reduced fertility and shorter siliques. Our findings provide genetic evidence that Hyp-linked arabinogalactan polysaccharide chains are critical for AGP function and clues to how arabinogalactan moieties of AGPs contribute to cell-to-cell communication during plant growth and development. PMID:25600942

  4. Marizomib, a potent second generation proteasome inhibitor from natural origin.

    PubMed

    Ma, Long; Diao, Aipo

    2014-11-14

    The malignance of cancers reinforces the need to find potent antineoplastic agents. In the past decades, proteasome has been witnessed as a potential target to fulfil this purpose, as evidenced by the fact the first-in-class proteasome inhibitor Bortezomib was marketed in 2003. Marizomib (Salinosporamide A, NPI-0052), as a marine natural product, promises to be of high efficacy against multiple myeloma (MM), relapsed/refractory MM and other types of solid tumours. Compared with Bortezomib, it arguably has fewer severe side effects. Marizomib has been granted orphan drug against multiple myeloma by US Food and Drug Administration (FDA) in 2013 and by European Medicines Agency (EMA) in 2014. As one of the second generation proteasome inhibitors (PIs), Marizomib is expected to bring about a sustained and complete therapeutic to extend cancer patients' life span. In this article, we intended to briefly review the historical developments, mechanisms, pharmacology, biosynthesis, side effects of this agent, aiming to provide concise coverage for a broad readership. In the end, we added our perspective for its futuristic applications. PMID:25403165

  5. Small Molecule Anticonvulsant Agents with Potent In Vitro Neuroprotection

    PubMed Central

    Smith, Garry R.; Zhang, Yan; Du, Yanming; Kondaveeti, Sandeep K.; Zdilla, Michael J.; Reitz, Allen B.

    2012-01-01

    Severe seizure activity is associated with recurring cycles of excitotoxicity and oxidative stress that result in progressive neuronal damage and death. Intervention to halt these pathological processes is a compelling disease-modifying strategy for the treatment of seizure disorders. In the present study, a core small molecule with anticonvulsant activity has been structurally optimized for neuroprotection. Phenotypic screening of rat hippocampal cultures with nutrient medium depleted of antioxidants was utilized as a disease model. Increased cell death and decreased neuronal viability produced by acute treatment with glutamate or hydrogen peroxide were prevented by our novel molecules. The neuroprotection associated with this chemical series has marked structure activity relationships that focus on modification of the benzylic position of a 2-phenyl-2-hydroxyethyl sulfamide core structure. Complete separation between anticonvulsant activity and neuroprotective action was dependent on substitution at the benzylic carbon. Chiral selectivity was evident in that the S-enantiomer of the benzylic hydroxy group had neither neuroprotective nor anticonvulsant activity, while the R-enantiomer of the lead compound had full neuroprotective action at ?40 nM and antiseizure activity in three animal models. These studies indicate that potent, multifunctional neuroprotective anticonvulsants are feasible within a single molecular entity. PMID:22535312

  6. [Contact dermatitis in children].

    PubMed

    Desmons, F

    1975-01-01

    After reviewing the frequency differences between the two great eczema varieties in child, in which atopic eczema develops in early childhood and contact dermatitis at age six, this work includes a total of 37 cases of atopic dermatitis observed within a period of three years in a "Pediatric Dermatology Service". Orto-ergic dermatitis (10 cases): Predominance in small children. Provoked by irritating drugs, hygiene products and synthetic clothing. Allergic dermatitis (27 cases): Most frequent at age six. Due to various sensitizing agents, drugs, sulphamids, antibiotics, phenotiazins, clothing, detergent and wild plants. There was a total of 27 cases of atopic dermatitis, divided in two groups in order to facilitate the diagnosis with patch tests. The first group included a total of 12 positives; the most common allergens were plastic materials, drugs, paraphenilendiamine and wild plants. Most of the group corresponded to drug induced dermatitis. A total of 15 cases were considered in the second group yielding doubtful results. In this group and causative agents most commonly involved were drugs and clothing (mainly shoewear). PMID:126641

  7. Contact Issue 8

    E-print Network

    Multiple Contributors

    1982-01-01

    ~ again .t~ ~~ue, and OM h~6e.U .than~ .to M~e Ve~k~ 6M .the j~.t-peJr.6ect ~ov~ duign. To OM ~eadeM, .than~ 6M YOM c.ontiYll.1.ed 6UppO~ and the LOC~ .to let ~ know how you 6eel. To you we'd Uke .to expf.a.in that be~~e. 06 ~eaUy demanding peMonal M....hedulu, CONTACT ~ oMen ~low in being mailed and ~ually f.a.te on pubUMtion, .too. We do .the bu.t we ~an and we do il 60~ you, to enjoy, .to ~hMe OM 6antMiu and dJt~. We'd Uke .to apologize 60~ .thue Mequent but a1wa.y~ unavoidable def.a.y~ (we' Jte no.t going...

  8. Optofluidic realization and retaining of cell–cell contact using an abrupt tapered optical fibre

    PubMed Central

    Xin, Hongbao; Zhang, Yao; Lei, Hongxiang; Li, Yayi; Zhang, Huixian; Li, Baojun

    2013-01-01

    Studies reveal that there exists much interaction and communication between bacterial cells, with parts of these social behaviors depending on cell–cell contacts. The cell–cell contact has proved to be crucial for determining various biochemical processes. However, for cell culture with relatively low cell concentration, it is difficult to precisely control and retain the contact of a small group of cells. Particularly, the retaining of cell–cell contact is difficult when flows occur in the medium. Here, we report an optofluidic method for realization and retaining of Escherichia coli cell–cell contact in a microfluidic channel using an abrupt tapered optical fibre. The contact process is based on launching a 980-nm wavelength laser into the fibre, E. coli cells were trapped onto the fibre tip one after another, retaining cell–cell contact and forming a highly organized cell chain. The formed chains further show the ability as bio-optical waveguides. PMID:23771190

  9. Optofluidic realization and retaining of cell-cell contact using an abrupt tapered optical fibre

    NASA Astrophysics Data System (ADS)

    Xin, Hongbao; Zhang, Yao; Lei, Hongxiang; Li, Yayi; Zhang, Huixian; Li, Baojun

    2013-06-01

    Studies reveal that there exists much interaction and communication between bacterial cells, with parts of these social behaviors depending on cell-cell contacts. The cell-cell contact has proved to be crucial for determining various biochemical processes. However, for cell culture with relatively low cell concentration, it is difficult to precisely control and retain the contact of a small group of cells. Particularly, the retaining of cell-cell contact is difficult when flows occur in the medium. Here, we report an optofluidic method for realization and retaining of Escherichia coli cell-cell contact in a microfluidic channel using an abrupt tapered optical fibre. The contact process is based on launching a 980-nm wavelength laser into the fibre, E. coli cells were trapped onto the fibre tip one after another, retaining cell-cell contact and forming a highly organized cell chain. The formed chains further show the ability as bio-optical waveguides.

  10. Contact Interactions at the LHC

    E-print Network

    Monica Vazquez Acosta

    2007-09-17

    Contact interactions offer a general framework for describing a new interaction with a scale above the energy scale probed. These interactions can occur if the Standard Model particles are composite or if new heavy particles are exchanged. The discovery potential of contact interactions at the LHC in dimuon and dijet final states at startup and the asymptotic reach are presented.

  11. Contact transformations for difference schemes

    E-print Network

    Decio Levi; Zora Thomova; Pavel Winternitz

    2011-10-15

    We define a class of transformations of the dependent and independent variables in an ordinary difference scheme. The transformations leave the solution set of the system invariant and reduces to a group of contact transformations in the continuous limit. We use a simple example to show that the class is not empty and that such "contact transformations for discrete systems" genuinely exist.

  12. Contact modeling for robotics applications

    SciTech Connect

    Lafarge, R.A.; Lewis, C.

    1998-08-01

    At Sandia National Laboratories (SNL), the authors are developing the ability to accurately predict motions for arbitrary numbers of bodies of arbitrary shapes experiencing multiple applied forces and intermittent contacts. In particular, the authors are concerned with the simulation of systems such as part feeders or mobile robots operating in realistic environments. Preliminary investigation of commercial dynamics software packages led them to the conclusion that they could use commercial software to provide everything they needed except for the contact model. They found that ADAMS best fit their needs for a simulation package. To simulate intermittent contacts, they need collision detection software that can efficiently compute the distances between non-convex objects and return the associated witness features. They also require a computationally efficient contact model for rapid simulation of impact, sustained contact under load, and transition to and from contact conditions. This paper provides a technical review of a custom hierarchical distance computation engine developed at Sandia, called the C-Space Toolkit (CSTk). In addition, they describe an efficient contact model using a non-linear damping term developed by SNL and Ohio State. Both the CSTk and the non-linear damper have been incorporated in a simplified two-body testbed code, which is used to investigate how to correctly model the contact using these two utilities. They have incorporated this model into the ADAMS software using the callable function interface. An example that illustrates the capabilities of the 9.02 release of ADAMS with their extensions is provided.

  13. CHARACTERIZING HUMAN CONTACT WITH SEDIMENT

    EPA Science Inventory

    People contact sediment during a variety of activities such as fishing, wading and boating. A number of default assumptions are used today to characterize dermal contact with sediments in terms of magnitude, frequency and duration. The accuracy of these default values are widel...

  14. Applied Research Contact Information

    Cancer.gov

    Skip to Main Content at the National Institutes of Health | www.cancer.gov Print Page E-mail Page Search: Please wait while this form is being loaded.... Home Browse by Resource Type Browse by Area of Research Research Networks Funding Information About

  15. PROSPR Contact Information

    Cancer.gov

    Skip to Main Content at the National Institutes of Health | www.cancer.gov Print Page E-mail Page Search: Please wait while this form is being loaded.... Home Browse by Resource Type Browse by Area of Research Research Networks Funding Information About

  16. Discrimination against contact lens wearers.

    PubMed

    Blais, B R

    1998-10-01

    Employers' attitudes toward the use of contact lenses at work have become less discriminatory as lenses have improved and numerous studies have demonstrated their safety, provided that additional personal protective equipment is used when necessary. In 1994, the Occupational Safety and Health Administration published its relevant Standard (29 CFR 1910), stating that "contact lenses do not pose additional hazards to the wearer...". Accommodations required by wearers of contact lenses must comply with Title I of the Americans with Disabilities Act. However, many companies still oppose their use. The recently published policy of the American College of Occupational and Environmental Medicine and the American Academy of Ophthalmology on the use of contact lenses should lead to their wider acceptance. Elements of a corporate contact lens policy are outlined. International aspects are summarized as well. PMID:9800172

  17. The nature of electrical interaction of Schottky contacts

    SciTech Connect

    Torkhov, N. A., E-mail: trkf@mail.ru [Research Institute of Semiconductor Devices (Russian Federation)

    2011-08-15

    Electrical interaction between metal-semiconductor contacts combined in a diode matrix with a Schottky barrier manifests itself in an appreciable variation in their surface potentials and static current-volt-characteristics. The necessary condition for appearance of electrical interaction between such contacts consists in the presence of a peripheral electric field (a halo) around them; this field propagates to a fairly large distances (<30 {mu}m). The sufficient condition is the presence of regions where the above halos overlap. It has been shown that variation in the surface potential and the current-voltage characteristics of contacts occurs under the effect of the intrinsic electric field of the contact's periphery and also under the effect of an electric field at matrix periphery; the latter field is formed as a result of superposition of electric fields of halos which form its contacts. The degree of the corresponding effect is governed by the distance between contacts and by the total charge of the space charge regions for all contacts of the matrix: their number, sizes (diameter D{sub i,j}), concentration of doping impurities in the semiconductor N{sub D}, and physical nature of a metal-semiconductor system with a Schottky barrier (with the barrier height {phi}{sub b}). It is established that bringing the contacts closer leads to a relative decrease in the threshold value of the 'dead' zone in the forward current-voltage characteristics, an increase in the effective height of the barrier, and an insignificant increase in the nonideality factor. An increase in the total area of contacts (a total electric charge in the space charge region) in the matrix brings about an increase in the threshold value of the 'dead' zone, a relative decrease in the effective barrier height, and an insignificant increase in the ideality factor.

  18. Tax Forms

    NSDL National Science Digital Library

    Ledvina, Mary Jane.

    As thoughts in the US turn to taxes (April 15 is just around the corner), Mary Jane Ledvina of the Louisiana State University regional government depository library has provided a simple, effective pointers page to downloadable tax forms. Included are federal tax forms and those for 43 states. Of course, available forms vary by state. Most forms are in Adobe Acrobat (.pdf) format. This is a simple, crisply designed page that should save time, although probably not headaches.

  19. Method and apparatus for high-efficiency direct contact condensation

    DOEpatents

    Bharathan, Desikan (Lakewood, CO); Parent, Yves (Golden, CO); Hassani, A. Vahab (Golden, CO)

    1999-01-01

    A direct contact condenser having a downward vapor flow chamber and an upward vapor flow chamber, wherein each of the vapor flow chambers includes a plurality of cooling liquid supplying pipes and a vapor-liquid contact medium disposed thereunder to facilitate contact and direct heat exchange between the vapor and cooling liquid. The contact medium includes a plurality of sheets arranged to form vertical interleaved channels or passageways for the vapor and cooling liquid streams. The upward vapor flow chamber also includes a second set of cooling liquid supplying pipes disposed beneath the vapor-liquid contact medium which operate intermittently in response to a pressure differential within the upward vapor flow chamber. The condenser further includes separate wells for collecting condensate and cooling liquid from each of the vapor flow chambers. In alternate embodiments, the condenser includes a cross-current flow chamber and an upward flow chamber, a plurality of upward flow chambers, or a single upward flow chamber. The method of use of the direct contact condenser of this invention includes passing a vapor stream sequentially through the downward and upward vapor flow chambers, where the vapor is condensed as a result of heat exchange with the cooling liquid in the contact medium. The concentration of noncondensable gases in the resulting condensate-liquid mixtures can be minimized by controlling the partial pressure of the vapor, which depends in part upon the geometry of the vapor-liquid contact medium. In another aspect of this invention, the physical and chemical performance of a direct contact condenser can be predicted based on the vapor and coolant compositions, the condensation conditions. and the geometric properties of the contact medium.

  20. An analytical method for computing atomic contact areas in biomolecules.

    PubMed

    Mach, Paul; Koehl, Patrice

    2013-01-15

    We propose a new analytical method for detecting and computing contacts between atoms in biomolecules. It is based on the alpha shape theory and proceeds in three steps. First, we compute the weighted Delaunay triangulation of the union of spheres representing the molecule. In the second step, the Delaunay complex is filtered to derive the dual complex. Finally, contacts between spheres are collected. In this approach, two atoms i and j are defined to be in contact if their centers are connected by an edge in the dual complex. The contact areas between atom i and its neighbors are computed based on the caps formed by these neighbors on the surface of i; the total area of all these caps is partitioned according to their spherical Laguerre Voronoi diagram on the surface of i. This method is analytical and its implementation in a new program BallContact is fast and robust. We have used BallContact to study contacts in a database of 1551 high resolution protein structures. We show that with this new definition of atomic contacts, we generate realistic representations of the environments of atoms and residues within a protein. In particular, we establish the importance of nonpolar contact areas that complement the information represented by the accessible surface areas. This new method bears similarity to the tessellation methods used to quantify atomic volumes and contacts, with the advantage that it does not require the presence of explicit solvent molecules if the surface of the protein is to be considered. © 2012 Wiley Periodicals, Inc. PMID:22965816

  1. Method and apparatus for high-efficiency direct contact condensation

    DOEpatents

    Bharathan, D.; Parent, Y.; Hassani, A.V.

    1999-07-20

    A direct contact condenser having a downward vapor flow chamber and an upward vapor flow chamber, wherein each of the vapor flow chambers includes a plurality of cooling liquid supplying pipes and a vapor-liquid contact medium disposed thereunder to facilitate contact and direct heat exchange between the vapor and cooling liquid. The contact medium includes a plurality of sheets arranged to form vertical interleaved channels or passageways for the vapor and cooling liquid streams. The upward vapor flow chamber also includes a second set of cooling liquid supplying pipes disposed beneath the vapor-liquid contact medium which operate intermittently in response to a pressure differential within the upward vapor flow chamber. The condenser further includes separate wells for collecting condensate and cooling liquid from each of the vapor flow chambers. In alternate embodiments, the condenser includes a cross-current flow chamber and an upward flow chamber, a plurality of upward flow chambers, or a single upward flow chamber. The method of use of the direct contact condenser of this invention includes passing a vapor stream sequentially through the downward and upward vapor flow chambers, where the vapor is condensed as a result of heat exchange with the cooling liquid in the contact medium. The concentration of noncondensable gases in the resulting condensate-liquid mixtures can be minimized by controlling the partial pressure of the vapor, which depends in part upon the geometry of the vapor-liquid contact medium. In another aspect of this invention, the physical and chemical performance of a direct contact condenser can be predicted based on the vapor and coolant compositions, the condensation conditions, and the geometric properties of the contact medium. 39 figs.

  2. Discovery of potent broad spectrum antivirals derived from marine actinobacteria.

    PubMed

    Raveh, Avi; Delekta, Phillip C; Dobry, Craig J; Peng, Weiping; Schultz, Pamela J; Blakely, Pennelope K; Tai, Andrew W; Matainaho, Teatulohi; Irani, David N; Sherman, David H; Miller, David J

    2013-01-01

    Natural products provide a vast array of chemical structures to explore in the discovery of new medicines. Although secondary metabolites produced by microbes have been developed to treat a variety of diseases, including bacterial and fungal infections, to date there has been limited investigation of natural products with antiviral activity. In this report, we used a phenotypic cell-based replicon assay coupled with an iterative biochemical fractionation process to identify, purify, and characterize antiviral compounds produced by marine microbes. We isolated a compound from Streptomyces kaviengensis, a novel actinomycetes isolated from marine sediments obtained off the coast of New Ireland, Papua New Guinea, which we identified as antimycin A1a. This compound displays potent activity against western equine encephalitis virus in cultured cells with half-maximal inhibitory concentrations of less than 4 nM and a selectivity index of greater than 550. Our efforts also revealed that several antimycin A analogues display antiviral activity, and mechanism of action studies confirmed that these Streptomyces-derived secondary metabolites function by inhibiting the cellular mitochondrial electron transport chain, thereby suppressing de novo pyrimidine synthesis. Furthermore, we found that antimycin A functions as a broad spectrum agent with activity against a wide range of RNA viruses in cultured cells, including members of the Togaviridae, Flaviviridae, Bunyaviridae, Picornaviridae, and Paramyxoviridae families. Finally, we demonstrate that antimycin A reduces central nervous system viral titers, improves clinical disease severity, and enhances survival in mice given a lethal challenge with western equine encephalitis virus. Our results provide conclusive validation for using natural product resources derived from marine microbes as source material for antiviral drug discovery, and they indicate that host mitochondrial electron transport is a viable target for the continued development of broadly active antiviral compounds. PMID:24349254

  3. Potent antioxidant role of pirfenidone in experimental cirrhosis.

    PubMed

    Salazar-Montes, Adriana; Ruiz-Corro, Luis; López-Reyes, Alberto; Castrejón-Gómez, Eugenio; Armendáriz-Borunda, Juan

    2008-10-24

    Three important features must be considered when proposing therapeutic strategies in liver cirrhosis: inflammation, oxidative stress and fibrogenesis. Pirfenidone is a synthetic molecule which oxidative action has not been tested in cirrhosis. Cirrhosis was induced in rats by ligation of the common bile duct or carbon tetrachloride (CCl(4)) chronic intoxication and treated with pirfenidone or diphenyleneiodonium (a potent known antioxidant) for the last two weeks for bile duct ligation model or for the last three weeks for CCl(4) chronic intoxication. A 60% reduction in fibrosis index for bile duct ligation model and 42% for CCl(4) along with reduced inflammation was observed. Considerable reduction on hepatic enzymes and total and direct bilirubins were detected with pirfenidone in both models. Pirfenidone antioxidant capacity rendered a 28% and 30% reduction in nitrites and malonyldealdehide concentration in bile duct ligation and 52% and 38% in CCl(4). With respect to gene expression, fibrotic genes like transforming growth factor-beta (TGF-beta) and collagen Ialpha (Col-1alpha) were down-regulated by pirfenidone and increased expression of regenerative genes like hepatocyte growth factor (HGF) and c-met . Superoxide dismutase (SOD), catalase (CAT) and inducible nitric oxide synthase (iNOS) gene expression were importantly down-regulated where nuclear factor kappa B (NF-kappaB) binding activity also decreased with pirfenidone treatment. Also, SOD and CAT functional activity decreased after pirfenidone action. On the other hand, diphenyleneiodonium induced a drop in oxidative stress similar in extent to pirfenidone, but it was not as effective as pirfenidone in reducing fibrosis. In this work, we showed antioxidant properties of pirfenidone beyond its well-known antifibrotic effect. These features make pirfenidone an attractive drug for trying fibrotic diseases accompanied by oxidative stress processes. PMID:18652820

  4. Anticancer agents are potent neurotoxins in vitro and in vivo.

    PubMed

    Rzeski, Wojciech; Pruskil, Susanne; Macke, Alexander; Felderhoff-Mueser, Ursula; Reiher, Anne Katrin; Hoerster, Friederike; Jansma, Corina; Jarosz, Bozena; Stefovska, Vanya; Bittigau, Petra; Ikonomidou, Chrysanthy

    2004-09-01

    Neurotoxicity of anticancer agents complicates treatment of children with cancer. We investigated neurotoxic effects of common cytotoxic drugs in neuronal cultures and in the developing rat brain. When neurons were exposed to cisplatin (5-100 microM), cyclophosphamide (5-100 microM), methotrexate (5-100 microM), vinblastin (0.1-1 microM), or thiotepa (5-100 microM), a concentration-dependent neurotoxic effect was observed. Neurotoxicity was potentiated by nontoxic glutamate concentrations. The N-methyl-D-aspartate receptor antagonist MK 801 (10 microM), the AMPA receptor antagonists GYKI 52466 (10 microM) and NBQX (10 microM), and the pancaspase inhibitor Ac-DEVD-CHO (1 nM) ameliorated neurotoxicity of cytotoxic drugs. To investigate neurotoxicity in vivo, we administered to 7-day-old rats the following: cisplatin (5-15 mg/kg i.p.), cyclophosphamide (200-600 mg/kg i.p.), thiotepa (15-45 mg/kg), or ifosfamide (100-500 mg/kg) and their brains were analyzed at 4 to 24 hours. Cytotoxic drugs produced widespread lesions within cortex, thalamus, hippocampal dentate gyrus, and caudate nucleus in a dose-dependent fashion. Early histological analysis demonstrated dendritic swelling and relative preservation of axonal terminals, which are morphological features indicating excitotoxicity. After longer survival periods, degenerating neurons displayed morphological features consistent with active cell death. These results demonstrate that anticancer drugs are potent neurotoxins in vitro and in vivo; they activate excitotoxic mechanisms but also trigger active neuronal death. PMID:15349862

  5. Dynorphin–Still an Extraordinarily Potent Opioid Peptide

    PubMed Central

    2013-01-01

    This issue of Molecular Pharmacology is dedicated to Dr. Avram Goldstein, the journal’s founding editor and one of the leaders in the development of modern pharmacology. This article focuses on his contributions to the discovery of the dynorphins and evidence that members of this family of opioid peptides are endogenous agonists for the kappa opioid receptor. In his original publication describing the purification and sequencing of dynorphin A, Avram described this peptide as ”extraordinarily potent” (“dyn” from the Greek, dynamis = power and “orphin” for endogenous morphine peptide). The name originally referred to its high affinity and great potency in the bioassay that was used to follow its activity during purification, but the name has come to have a second meaning: studies of its physiologic function in brain continue to provide powerful insights to the molecular mechanisms controlling mood disorders and drug addiction. During the 30 years since its discovery, we have learned that the dynorphin peptides are released in brain during stress exposure. After they are released, they activate kappa opioid receptors distributed throughout the brain and spinal cord, where they trigger cellular responses resulting in different stress responses: analgesia, dysphoria-like behaviors, anxiety-like responses, and increased addiction behaviors in experimental animals. Avram predicted that a detailed molecular analysis of opiate drug actions would someday lead to better treatments for drug addiction, and he would be gratified to know that subsequent studies enabled by his discovery of the dynorphins resulted in insights that hold great promise for new treatments for addiction and depressive disorders. PMID:23152558

  6. Elastohydrodynamic lubrication of elliptical contacts

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1981-01-01

    The determination of the minimum film thickness within contact is considered for both fully flooded and starved conditions. A fully flooded conjunction is one in which the film thickness is not significantly changed when the amount of lubricant is increased. The fully flooded results presented show the influence of contact geometry on minimum film thickness as expressed by the ellipticity parameter and the dimensionless speed, load, and materials parameters. These results are applied to materials of high elastic modulus (hard EHL), such as metal, and to materials of low elastic modulus(soft EHL), such as rubber. In addition to the film thickness equations that are developed, contour plots of pressure and film thickness are given which show the essential features of elastohydrodynamically lubricated conjunctions. The crescent shaped region of minimum film thickness, with its side lobes in which the separation between the solids is a minimum, clearly emerges in the numerical solutions. In addition to the 3 presented for the fully flooded results, 15 more cases are used for hard EHL contacts and 18 cases are used for soft EHL contacts in a theoretical study of the influence of lubricant starvation on film thickness and pressure. From the starved results for both hard and soft EHL contacts, a simple and important dimensionless inlet boundary distance is specified. This inlet boundary distance defines whether a fully flooded or a starved condition exists in the contact. Contour plots of pressure and film thickness in and around the contact are shown for conditions.

  7. Contact mechanics of rough spheres

    NASA Astrophysics Data System (ADS)

    Pastewka, Lars; Robbins, Mark

    2013-03-01

    We use large scale numerical calculations to study the contact mechanics of rough spheres on flat elastic solids. Such geometries are encountered in systems that range from ball bearings to atomic force microscope tips, but the influence of roughness is seldom considered explicitly. Our calculations show that the contact area A grows linearly with load N at small loads and crosses over to Hertzian behavior A N^2/3 at large loads. The total contact stiffness is defined as K = dN/dz where z is the normal displacement of the sphere. It shows power-law K N^? behavior at all loads with an exponent ? that is close to the value of 1/3 expected from Hertzian contact mechanics. The results are discussed in the context of recent theories for flat rough contacts [1] and Greenwood-Williams theory as modified for spherical contacts [2]. [4pt] [1] B.N.J. Persson, J. Chem. Phys. 115, 3840 (2001); S. Hyun, L. Pei, J.-F. Molinari, M.O. Robbins, Phys. Rev. E 70, 026117 (2004); S. Akarapu, T. Sharp, M.O. Robbins, Phys. Rev. Lett. 106, 204301 (2011) [0pt] [2] K.L. Johnson, Contact Mechanics, Cambridge University Press, 1987

  8. The Kinematics of Contact and Grasp

    Microsoft Academic Search

    David J. Montana

    1988-01-01

    The kinematics of contact describe the motion of a point of contact over the surfaces of two contacting objects in response to a relative motion of these objects. Using concepts from differential geometry, I derive a set of equations, called the contact equations, that embody this relationship. I employ the contact equations to design the following applications to be executed

  9. Measuring The Contact Resistances Of Photovoltaic Cells

    NASA Technical Reports Server (NTRS)

    Burger, D. R.

    1985-01-01

    Simple method devised to measure contact resistances of photovoltaic solar cells. Method uses readily available equipment and applicable at any time during life of cell. Enables evaluation of cell contact resistance, contact-end resistance, contact resistivity, sheet resistivity, and sheet resistivity under contact.

  10. Back contact buffer layer for thin-film solar cells

    SciTech Connect

    Compaan, Alvin D.; Plotnikov, Victor V.

    2014-09-09

    A photovoltaic cell structure is disclosed that includes a buffer/passivation layer at a CdTe/Back contact interface. The buffer/passivation layer is formed from the same material that forms the n-type semiconductor active layer. In one embodiment, the buffer layer and the n-type semiconductor active layer are formed from cadmium sulfide (CdS). A method of forming a photovoltaic cell includes the step of forming the semiconductor active layers and the buffer/passivation layer within the same deposition chamber and using the same material source.

  11. Using Tutte polynomials to characterize sexual contact networks

    NASA Astrophysics Data System (ADS)

    Cadavid Muñoz, Juan José

    2014-06-01

    Tutte polynomials are used to characterize the dynamic and topology of the sexual contact networks, in which pathogens are transmitted as an epidemic. Tutte polynomials provide an algebraic characterization of the sexual contact networks and allow the projection of spread control strategies for sexual transmission diseases. With the usage of Tutte polynomials, it allows obtaining algebraic expressions for the basic reproductive number of different pathogenic agents. Computations are done using the computer algebra software Maple, and it's GraphTheory Package. The topological complexity of a contact network is represented by the algebraic complexity of the correspondent polynomial. The change in the topology of the contact network is represented as a change in the algebraic form of the associated polynomial. With the usage of the Tutte polynomials, the number of spanning trees for each contact network can be obtained. From the obtained results in the polynomial form, it can be said that Tutte polynomials are of great importance for designing and implementing control measures for slowing down the propagation of sexual transmitted pathologies. As a future research line, the analysis of weighted sexual contact networks using weighted Tutte polynomials is considered.

  12. First principles study of metal contacts to monolayer black phosphorous

    NASA Astrophysics Data System (ADS)

    Chanana, Anuja; Mahapatra, Santanu

    2014-11-01

    Atomically thin layered black phosphorous (BP) has recently appeared as an alternative to the transitional metal dichalcogenides for future channel material in a metal-oxide-semiconductor transistor due to its lower carrier effective mass. Investigation of the electronic property of source/drain contact involving metal and two-dimensional material is essential as it impacts the transistor performance. In this paper, we perform a systematic and rigorous study to evaluate the Ohmic nature of the side-contact formed by the monolayer BP (mBP) and metals (gold, titanium, and palladium), which are commonly used in experiments. Employing the Density Functional Theory, we analyse the potential barrier, charge transfer and atomic orbital overlap at the metal-mBP interface in an optimized structure to understand how efficiently carriers could be injected from metal contact to the mBP channel. Our analysis shows that gold forms a Schottky contact with a higher tunnel barrier at the interface in comparison to the titanium and palladium. mBP contact with palladium is found to be purely Ohmic, where as titanium contact demonstrates an intermediate behaviour.

  13. Newton constant, contact terms and entropy

    E-print Network

    Sergey N. Solodukhin

    2015-03-02

    We discuss the renormalization of the Newton constant due to fields of various spin $s$. We first briefly review the cases of $s=0, \\, 1/2, \\, 1,\\, 3/2$ already discussed in the literature and notice the appearance of the well-known contact terms for the vector bosons. We then extend this discussion of the contact terms to massive vector fields, $p$-forms and to the case of spin $s=2$ particles (gravitons). We observe that, in general, the contact terms originate from the fields which mediate the interactions (such as vector gauge bosons and gravitons). We then discuss entanglement entropy and the conical entropy and their relation to the renormalized Newton constant. We address the puzzle of the non-analytic terms due to fields of spin $s=2$ and suggest that the resolution of this puzzle comes from the non-equivalence of the orbifold and $n$-fold cover constructions which are used in the entropy calculations. Finally, we propose a mechanism by which the Bekenstein-Hawking entropy is identified with entanglement entropy in any theory which includes both matter fields and the mediators of interactions (vector gauge bosons and gravitons).

  14. Schottky contacts to In2O3

    NASA Astrophysics Data System (ADS)

    von Wenckstern, H.; Splith, D.; Schmidt, F.; Grundmann, M.; Bierwagen, O.; Speck, J. S.

    2014-04-01

    n-type binary compound semiconductors such as InN, InAs, or In2O3 are especial because the branch-point energy or charge neutrality level lies within the conduction band. Their tendency to form a surface electron accumulation layer prevents the formation of rectifying Schottky contacts. Utilizing a reactive sputtering process in an oxygen-containing atmosphere, we demonstrate Schottky barrier diodes on indium oxide thin films with rectifying properties being sufficient for space charge layer spectroscopy. Conventional non-reactive sputtering resulted in ohmic contacts. We compare the rectification of Pt, Pd, and Au Schottky contacts on In2O3 and discuss temperature-dependent current-voltage characteristics of Pt/In2O3 in detail. The results substantiate the picture of oxygen vacancies being the source of electrons accumulating at the surface, however, the position of the charge neutrality level and/or the prediction of Schottky barrier heights from it are questioned.

  15. RV Piscium: a marginal contact binary system

    NASA Astrophysics Data System (ADS)

    He, Jiajia; Qian, Shengbang

    2009-06-01

    The first complete charge-coupled device (CCD) light curves in B and V bands of the short-period binary system, RV Psc, are presented. It is found that the light curves of RV Psc are symmetric and belong to the EW type rather than the EA type as described in the 4th edition of the GCVS. Photometric solutions were derived by using the 2003 version of the Wilson-Devinney (W-D) method. It is shown that RV Psc is a marginal contact system ( f=5.8%±6.6%) with a mass ratio of q=0.5978±0.0096. The temperature difference between both components is only 17 K. Analysis of the O-C curve suggests that the period of RV Psc shows a long-term continuous decrease at a rate of dP/ dt=-5.89×10-8 days/year. The long-time period decrease, the marginal-contact configuration, and the astrophysical parameters of the binary system, all suggest that it is a newly formed marginal contact binary from a case A mass transfer and will evolve into a normal overcontact binary.

  16. Details of Forestry Commission and DARDNI Plant Health Contacts for UK Points of Entry UK Principle Ports Contacts Contact Details

    E-print Network

    Details of Forestry Commission and DARDNI Plant Health Contacts for UK Points of Entry UK Principle Ports Contacts Contact Details Felixstowe Richard Fergusson Pat Mitchell Philip Evans Roland Fry Fax

  17. Wraparound-contact solar cells

    NASA Technical Reports Server (NTRS)

    Baraona, C. R.; Klucher, T. M.; Thornhill, J. W.; Scott-Monck, J.

    1979-01-01

    Positive and negative electrical contacts are on back surface of wraparound-contact solar cell. With both terminals on nonilluminated side, cells can be connected back-to-back, and interconnection of many cells can be automated by using printed-circuit techniques. Cells are made by screen-printing layer of dielectric around edge of cell and extending top contact over dielectric to back surface. Wraparound also facilitates application of transparent covers and encapsulants. Efficiencies of cells are in excess of seventeen percent.

  18. Morphology and the Strength of Intermolecular Contact in Protein Crystals

    NASA Technical Reports Server (NTRS)

    Matsuura, Yoshiki; Chernov, Alexander A.

    2002-01-01

    The strengths of intermolecular contacts (macrobonds) in four lysozyme crystals were estimated based on the strengths of individual intermolecular interatomic interaction pairs. The periodic bond chain of these macrobonds accounts for the morphology of protein crystals as shown previously. Further in this paper, the surface area of contact, polar coordinate representation of contact site, Coulombic contribution on the macrobond strength, and the surface energy of the crystal have been evaluated. Comparing location of intermolecular contacts in different polymorphic crystal modifications, we show that these contacts can form a wide variety of patches on the molecular surface. The patches are located practically everywhere on this surface except for the concave active site. The contacts frequently include water molecules, with specific intermolecular hydrogen-bonds on the background of non-specific attractive interactions. The strengths of macrobonds are also compared to those of other protein complex systems. Making use of the contact strengths and taking into account bond hydration we also estimated crystal-water interfacial energies for different crystal faces.

  19. Discoipyrroles A-D: Isolation, Structure Determination and Synthesis of Potent Migration Inhibitors from Bacillus hunanensis

    PubMed Central

    Hu, Youcai; Potts, Malia B.; Colosimo, Dominic; Herrera-Herrera, Mireya L.; Legako, Aaron G.; Yousufuddin, Muhammed; White, Michael A.; MacMillan, John B.

    2013-01-01

    Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase involved in a variety of cellular response pathways, including regulation of cell growth, proliferation and motility. Using a newly developed platform to identify the signaling pathway/molecular target of natural products, we identified a family of alkaloid natural products, discoipyrroles A–D (1–4), from Bacillus hunanensis that inhibit the DDR2 signaling pathway. The structure of 1–4, determined by detailed 2D NMR methods and confirmed by X-ray crystallographic analysis has an unusual 3H-benzo[ d]pyrrolo][1,3]oxazine-3,5-dione core. Discoipyrroles A–D potently inhibit DDR2 dependent migration of BR5 fibroblasts and show selective cytotoxicity to DDR2 mutant cell lung cancer cell lines (IC50 120–400 nM). Examination of the biosynthesis has led to the conclusion that the discoipyrroles are formed through a non-enzymatic process, leading to a one-pot total synthesis of 1. PMID:23984625

  20. Clostridium perfringens epsilon toxin: the third most potent bacterial toxin known.

    PubMed

    Alves, Guilherme Guerra; Machado de Ávila, Ricardo Andrez; Chávez-Olórtegui, Carlos Delfin; Lobato, Francisco Carlos Faria

    2014-12-01

    Epsilon toxin (ETX) is produced by Clostridium perfringens type B and D strains and causes enterotoxemia, a highly lethal disease with major impacts on the farming of domestic ruminants, particularly sheep. ETX belongs to the aerolysin-like pore-forming toxin family. Although ETX has striking similarities to other toxins in this family, ETX is often more potent, with an LD50 of 100 ng/kg in mice. Due to this high potency, ETX is considered as a potential bioterrorism agent and has been classified as a category B biological agent by the Centers for Disease Control and Prevention (CDC) of the United States. The protoxin is converted to an active toxin through proteolytic cleavage performed by specific proteases. ETX is absorbed and acts locally in the intestines then subsequently binds to and causes lesions in other organs, including the kidneys, lungs and brain. The importance of this toxin for veterinary medicine and its possible use as a biological weapon have drawn the attention of researchers and have led to a large number of studies investigating ETX. The aim of the present work is to review the existing knowledge on ETX from C. perfringens type B and D. PMID:25234332

  1. Developing Potent Human Uric Acid Transporter 1 (hURAT1) Inhibitors

    PubMed Central

    Wempe, Michael F.; Jutabha, Promsuk; Quade, Bettina; Iwen, Timothy J.; Frick, Morin M.; Ross, Ian R.; Rice, Peter J.; Anzai, Naohiko; Endou, Hitoshi

    2011-01-01

    The kidneys are a vital organ in the human body. They serve several purposes including homeostatic functions such as regulating extracellular fluid volume, maintaining acid-base and electrolyte balance, and are essential regarding the excretion of metabolic waste. Furthermore, the kidneys play an important role in uric acid secretion/re-absorption. Abnormalities associated with kidney transporters have been associated with various diseases, such as gout. The current study utilized Xenopus oocytes expressing human uric acid transporter 1 (hURAT1; SLC22A12) as an in vitro method to investigate novel compounds and their ability to inhibit 14C-uric acid uptake via hURAT1. We have prepared and tested a series of 2-ethyl-benzofuran compounds and probed the hURAT1 in vitro inhibitor structure-activity relationship (SAR). Compared to di-methoxy analogs, mono-phenols formed on the C-Ring showed the best in vitro inhibitory potential. Compounds with sub-micromolar (i.e. IC50 < 1000 nM) inhibitors were prepared by brominating the corresponding phenols to produce compounds with potent uricosuric activity. PMID:21449597

  2. Developing potent human uric acid transporter 1 (hURAT1) inhibitors.

    PubMed

    Wempe, Michael F; Jutabha, Promsuk; Quade, Bettina; Iwen, Timothy J; Frick, Morin M; Ross, Ian R; Rice, Peter J; Anzai, Naohiko; Endou, Hitoshi

    2011-04-28

    The kidneys are a vital organ in the human body. They serve several purposes including homeostatic functions such as regulating extracellular fluid volume and maintaining acid-base and electrolyte balance and are essential regarding the excretion of metabolic waste. Furthermore, the kidneys play an important role in uric acid secretion/reabsorption. Abnormalities associated with kidney transporters have been associated with various diseases, such as gout. The current study utilized Xenopus oocytes expressing human uric acid transporter 1 (hURAT1; SLC22A12) as an in vitro method to investigate novel compounds and their ability to inhibit (14)C-uric acid uptake via hURAT1. We have prepared and tested a series of 2-ethyl-benzofuran compounds and probed the hURAT1 in vitro inhibitor structure-activity relationship. As compared to dimethoxy analogues, monophenols formed on the C ring showed the best in vitro inhibitory potential. Compounds with submicromolar (i.e., IC(50) < 1000 nM) inhibitors were prepared by brominating the corresponding phenols to produce compounds with potent uricosuric activity. PMID:21449597

  3. The 2?-Trifluoromethyl Analogue of Indomethacin Is a Potent and Selective COX-2 Inhibitor

    PubMed Central

    2013-01-01

    Indomethacin is a potent, time-dependent, nonselective inhibitor of the cyclooxygenase enzymes (COX-1 and COX-2). Deletion of the 2?-methyl group of indomethacin produces a weak, reversible COX inhibitor, leading us to explore functionality at that position. Here, we report that substitution of the 2?-methyl group of indomethacin with trifluoromethyl produces CF3–indomethacin, a tight-binding inhibitor with kinetic properties similar to those of indomethacin and unexpected COX-2 selectivity (IC50 mCOX-2 = 267 nM; IC50 oCOX-1 > 100 ?M). Studies with site-directed mutants reveal that COX-2 selectivity results from insertion of the CF3 group into a small hydrophobic pocket formed by Ala-527, Val-349, Ser-530, and Leu-531 and projection of the methoxy group toward a side pocket bordered by Val-523. CF3–indomethacin inhibited COX-2 activity in human head and neck squamous cell carcinoma cells and exhibited in vivo anti-inflammatory activity in the carrageenan-induced rat paw edema model with similar potency to that of indomethacin. PMID:23687559

  4. Supramolecular assembly of multifunctional maspin-mimetic nanostructures as a potent peptide-based angiogenesis inhibitor.

    PubMed

    Zha, R Helen; Sur, Shantanu; Boekhoven, Job; Shi, Heidi Y; Zhang, Ming; Stupp, Samuel I

    2015-01-01

    Aberrant angiogenesis plays a large role in pathologies ranging from tumor growth to macular degeneration. Anti-angiogenic proteins have thus come under scrutiny as versatile, potent therapeutics but face problems with purification and tissue retention. We report here on the synthesis of supramolecular nanostructures that mimic the anti-angiogenic activity of maspin, a class II tumor suppressor protein. These maspin-mimetic nanostructures are formed via self-assembly of small peptide amphiphiles containing the g-helix motif of maspin. Using tubulogenesis assays with human umbilical vein endothelial cells, we demonstrate that maspin-mimetic nanostructures show anti-angiogenic activity at concentrations that are significantly lower than those necessary for the g-helix peptide. Furthermore, in vivo assays in the chick chorioallantoic membrane show maspin-mimetic nanostructures to be effective over controls at inhibiting angiogenesis. Thus, the nanostructures investigated here offer an attractive alternative to the use of anti-angiogenic recombinant proteins in the treatment of cancer or other diseases involving abnormal blood vessel formation. PMID:25462852

  5. BINOL-amino acid conjugates as triggerable carriers of DNA-targeted potent photocytotoxic agents.

    PubMed

    Doria, Filippo; Richter, Sara N; Nadai, Matteo; Colloredo-Mels, Stefano; Mella, Mariella; Palumbo, Manlio; Freccero, Mauro

    2007-12-27

    Mild photoactivation of new BINOL-amino acid and -amino ester conjugates (BINOLAMs) yielded alkylating and DNA cross-linking agents with high photoefficiency and superior cytotoxicity. Detection of the transient electrophile, by laser flash photolysis (LFP), suggests that BINOL-quinone methides (QMs) are key intermediates in the process. QMs trapping by water, monitored in a time-dependent product distribution analysis, demonstrated that the phototriggered reactivity of BINOLAMs as bis-alkylating agents is the result of a two-step process involving sequential photogeneration of monoalkylating QMs. Light activation of the BINOL-L-amino esters produced cytotoxic QMs very effective against human tumor LoVo cells with EC50 in the 130-230 nM range. Trimethylpsoralen (PS) is about 4 times less potent than our newly tested compounds. BINOL-L-proline methyl ester showed notable photoselectivity because it displayed cytotoxic effects upon irradiation only and was able to efficiently reach the target DNA inside the cells, where it forms both alkylated and cross-linked species. PMID:18047263

  6. Glycosylated enfuvirtide: a long-lasting glycopeptide with potent anti-HIV activity.

    PubMed

    Cheng, Shuihong; Chang, Xuesong; Wang, Yan; Gao, George F; Shao, Yiming; Ma, Liying; Li, Xuebing

    2015-02-12

    Many peptide-based therapeutics have short circulatory half-lives. We report here that the pharmacokinetics of an anti-HIV peptide drug enfuvirtide (ENF) can be dramatically improved by a chemical glycosylation approach. A set of glycosylated ENFs with varying glycosylation sites and glycan structures were synthesized. Among these, a sialic acid-introduced peptide (SL-ENF) demonstrated a 15-fold extended half-life in rats relative to ENF (T1/2: 23.1 vs 1.5 h), and its antiviral potency was comparable to that of ENF (EC50: 2 vs 3 nM). SL-ENF bound to a functional fragment of the HIV fusogenic protein gp41 and formed complexes with high affinity and ?-helicity, revealing the mechanism behind its potent antiviral activity. Because it is widely accepted in biology that glycosylation protects proteins from denaturation and proteases, our approach may be useful for the development of novel protein and peptide drugs with enhanced pharmaceutical properties. PMID:25594223

  7. Contact Geometry of Hyperbolic Equations of Generic Type

    E-print Network

    Dennis The

    2008-08-19

    We study the contact geometry of scalar second order hyperbolic equations in the plane of generic type. Following a derivation of parametrized contact-invariants to distinguish Monge-Ampere (class 6-6), Goursat (class 6-7) and generic (class 7-7) hyperbolic equations, we use Cartan's equivalence method to study the generic case. An intriguing feature of this class of equations is that every generic hyperbolic equation admits at most a nine-dimensional contact symmetry algebra. The nine-dimensional bound is sharp: normal forms for the contact-equivalence classes of these maximally symmetric generic hyperbolic equations are derived and explicit symmetry algebras are presented. Moreover, these maximally symmetric equations are Darboux integrable. An enumeration of several submaximally symmetric (eight and seven-dimensional) generic hyperbolic structures is also given.

  8. Ball bearing lubrication: The elastohydrodynamics of elliptical contacts

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1981-01-01

    The history of ball bearings is examined, taking into account rollers and the wheel in the early civilizations, the development of early forms of rolling-element bearings in the classical civilizations, the Middle Ages, the Industrial Revolution, the emergence of the precision ball bearing, scientific studies of contact mechanics and rolling friction, and the past fifty years. An introduction to ball bearings is presented, and aspects of ball bearing mechanics are explored. Basic characteristics of lubrication are considered along with lubrication equations, the lubrication of rigid ellipsoidal solids, and elastohydrodynamic lubrication theory. Attention is given to the theoretical results for fully flooded elliptical hydrodynamic contacts, the theoretical results for starved elliptical contacts, experimental investigations, the elastohydrodynamics of elliptical contacts for materials of low elastic modulus, the film thickness for different regimes of fluid-film lubrication, and applications.

  9. Emerging magnetic order in platinum atomic contacts and chains

    PubMed Central

    Strigl, Florian; Espy, Christopher; Bückle, Maximilian; Scheer, Elke; Pietsch, Torsten

    2015-01-01

    The development of atomic-scale structures revealing novel transport phenomena is a major goal of nanotechnology. Examples include chains of atoms that form while stretching a transition metal contact or the predicted formation of magnetic order in these chains, the existence of which is still debated. Here we report an experimental study of the magneto-conductance (MC) and anisotropic MC with atomic-size contacts and mono-atomic chains of the nonmagnetic metal platinum. We find a pronounced and diverse MC behaviour, the amplitude and functional dependence change when stretching the contact by subatomic distances. These findings can be interpreted as a signature of local magnetic order in the chain, which may be of particular importance for the application of atomic-sized contacts in spintronic devices of the smallest possible size. PMID:25649440

  10. Contact Constraint Analysis and Determination of Geometrically Valid Contact Formations from

    E-print Network

    Xiao, Jing

    Contact Constraint Analysis and Determination of Geometrically Valid Contact Formations from Possible Contact Primitives Jing Xiaoy and Lixin Zhangz Abstract A complete, precise, and systematic analysis on the geometrical nature of contacts between two arbitrary polygons and derivation

  11. Information, Contact Paul Ferguson, Director,

    E-print Network

    Hutcheon, James M.

    , distractive driving including cell phone use/texting, speeding, risk reductions and other destructiveInformation, Contact Paul Ferguson, Director, Health Services Phone: 912-478-7288 Georgia Southern

  12. NCI: SBIR & STTR - Contact Us

    Cancer.gov

    Skip to main content Sign Up for Updates | Follow us on Twitter | Connect with us on LinkedIn | Contact Us | Site Map Search About Program Information Program Structure Goals Eligibility Criteria Employment Opportunities Meet the Team Funding Opportunities Find

  13. Contact Lens Use in Industry

    MedlinePLUS

    ... for updates. FS96 7/10 © 2010 Prevent Blindness America ® All rights reserved. According to the Contact Lens ... Occupational Safety and Health (NIOSH). Recommendations Prevent Blindness America makes the following recommendations to management that directs ...

  14. Model of contact transitioning with \\

    Microsoft Academic Search

    John P. Barber; Yuri A. Dreizin

    1995-01-01

    Arcing transition of metal-to-metal contacts is a key technical challenge in the development of railgun launchers. Theoretical understanding of the process remains poor and controversial. Several authors have explained transitioning by a velocity skin effect driven \\

  15. Racial Disparity in Police Contacts

    PubMed Central

    Crutchfield, Robert D.; Haggerty, Kevin P.; McGlynn, Anne; Catalano, Richard F.

    2013-01-01

    Criminologists agree the race disparity in arrests cannot be fully explained by differences in criminal behavior. We examine social environment factors that may lead to racial differences in police contact in early adolescence, including family, peers, school, and community. Data are from 331 8th-grade students. Blacks were almost twice as likely as Whites to report a police contact. Blacks reported more property crime but not more violent crime than Whites. Police contacts were increased by having a parent who had been arrested, a sibling involved in criminal activity, higher observed reward for negative behavior, having school disciplinary actions, and knowing adults who engaged in substance abuse or criminal behavior. Race differences in police contacts were partially attributable to more school discipline. PMID:24363956

  16. 5 CFR 2600.102 - Contact information.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Contact information. 2600.102 Section 2600...OF GOVERNMENT ETHICS § 2600.102 Contact information. (a) Address. ...Persons who are deaf or speech impaired may contact OGE at the following TDD...

  17. 5 CFR 2600.102 - Contact information.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Contact information. 2600.102 Section 2600...OF GOVERNMENT ETHICS § 2600.102 Contact information. (a) Address. ...Persons who are deaf or speech impaired may contact OGE at the following TDD...

  18. Table of Contents Welcome and contacts................................................................... 3

    E-print Network

    Lin, Zhiqun

    #12;- 2 - Table of Contents Welcome and contacts. Contact us if you have any questions. We look forward to working with you and hope that you enjoy your Learning Community experience. Contact Information LC Administration For general administrative questions

  19. 5 CFR 2600.102 - Contact information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Contact information. 2600.102 Section 2600...OF GOVERNMENT ETHICS § 2600.102 Contact information. (a) Address. ...Persons who are deaf or speech impaired may contact OGE at the following TDD...

  20. SARS Patients and Their Close Contacts

    MedlinePLUS

    ... Fact Sheet for SARS Patients and Their Close Contacts Format: Select one PDF [256 KB] Recommend on ... that are not now known. What does "close contact" mean? In the context of SARS, close contact ...

  1. Contact Information - Trans-NIH Angiogenesis Workshop

    Cancer.gov

    Meetings & Events Home Agenda Speaker Biosketches Abstracts Logistics Contact Contact Information POINT OF CONTACT Capital Consulting Corporation is providing logistical support for this meeting. If you have questions or need assistance,

  2. BUSINESS APPLICATION SECTION 1: BUSINESS CONTACT INFORMATION

    E-print Network

    Suzuki, Masatsugu

    BUSINESS APPLICATION SECTION 1: BUSINESS CONTACT INFORMATION Sponsor: Company Name: Contact Name: Contact Address: Phone | Fax E-mail Type of Business Sole proprietorship Corporation Partnership Limited Liability Company SECTION 2: BUSINESS INFORMATION New Business Existing NYS Business Expanding

  3. Method for lubricating contacting surfaces

    DOEpatents

    Dugger, Michael T. (Tijeras, NM); Ohlhausen, James A. (Albuquerque, NM); Asay, David B. (Boalsburg, PA); Kim, Seong H. (State College, PA)

    2011-12-06

    A method is provided for tribological lubrication of sliding contact surfaces, where two surfaces are in contact and in motion relative to each other, operating in a vapor-phase environment containing at least one alcohol compound at a concentration sufficiently high to provide one monolayer of coverage on at least one of the surfaces, where the alcohol compound continuously reacts at the surface to provide lubrication.

  4. Postural stabilization from fingertip contact

    Microsoft Academic Search

    François Tremblay; Annie-Claude Mireault; Liam Dessureault; Hélène Manning; Heidi Sveistrup

    2005-01-01

    In the present report, we extend our previous observations on the effect of age on postural stabilization from fingertip contact (Exp Brain Res 157 (2004) 275) to examine the possible influence of sensory thresholds measured at the fingertip on the magnitude of contact forces. Participants (young, n=25, 19–32 years; old, n=35, 60–86 years) underwent psychophysical testing of the right index finger to

  5. Contact flows and integrable systems

    NASA Astrophysics Data System (ADS)

    Jovanovi?, Božidar; Jovanovi?, Vladimir

    2015-01-01

    We consider Hamiltonian systems restricted to the hypersurfaces of contact type and obtain a partial version of the Arnold-Liouville theorem: the system need not be integrable on the whole phase space, while the invariant hypersurface is foliated on an invariant Lagrangian tori. In the second part of the paper we consider contact systems with constraints. As an example, the Reeb flows on Brieskorn manifolds are considered.

  6. 2,4-Dithiothymine as a potent UVA chemotherapeutic agent.

    PubMed

    Pollum, Marvin; Jockusch, Steffen; Crespo-Hernández, Carlos E

    2014-12-31

    Substitution of both oxygen atoms in the exocyclic carbonyl groups of the thymine chromophore by sulfur atoms results in a remarkable redshift of its absorption spectrum from an absorption maximum at 267 nm in thymidine to 363 nm in 2,4-dithiothymine (?E = 9905 cm(-1)). A single sulfur substitution of a carbonyl group in the thymine chromophore at position 2 or 4 results in a significantly smaller redshift in the absorption maximum, which depends sensitively on the position at which the sulfur atom is substituted, varying from 275 nm in 2-thiothymine to 335 nm in 4-thiothymidine. Femtosecond transient absorption spectroscopy reveals that excitation of 2,4-dithiothymine at 335 or 360 nm leads to the ultrafast population of the triplet state, with an intersystem crossing lifetime of 180 ± 40 fs—the shortest intersystem crossing lifetime of any DNA base derivative studied so far in aqueous solution. Surprisingly, the degree and position at which the sulfur atom is substituted have important effects on the magnitude of the intersystem crossing rate constant, showing a 1.2-, 3.2-, and 4.2-fold rate increases for 2-thiothymine, 4-thiothymidine, and 2,4-dithiothymine, respectively, relative to that of thymidine, whereas the triplet yield increases 60-fold to near unity, independent of the site of sulfur atom substitution. While the natural thymine monomers owe their high degree of photostability to ultrafast internal conversion to the ground state and low triplet yields, the near-unity triplet yields in the thiothymine series account for their potent photosensitization properties. Nanosecond time-resolved luminescence spectroscopy shows that 4-thiothymidine and 2,4-dithiothymine are efficient singlet oxygen generators, with singlet oxygen quantum yields of 0.42 ± 0.02 and 0.46 ± 0.02, respectively, in O2-saturated acetonitrile solution. Taken together, these photophysical measurements strongly suggest that 2,4-dithiothymine can act as a more effective UVA chemotherapeutic agent than the currently used 4-thiothymidine, especially in deeper-tissue chemotherapeutic applications. PMID:25506742

  7. Ohmic contacts for wide bandgap semiconductors: Processing, properties and mechanisms

    NASA Astrophysics Data System (ADS)

    Park, Mi-Ran

    Stable Ohmic contacts are essential for reliable operation of wide bandgap semiconductor electronic and optoelectronic devices. Such contacts have been made to molecular beam epitaxy (MBE) grown n-type and p-type ZnSe on (100) semi-insulating GaAs substrates and metalorganic chemical vapor deposition (MOCVD) grown p-type GaN on (0001) sapphire substrates. Various metals have been deposited by thermal evaporation and annealing techniques at different temperatures. Chemical etching and cleaning, plasma treatment using reactive ion etching (RIE), and cryogenic treatment in liquid nitrogen have been studied. Ion implantation was also performed to obtain highly doped materials. The electrical characteristics for the contacts were examined by the current versus voltage data and the specific contact resistance was determined by use of the transmission line method (TLM) for II-VI n-type and p-type ZnSe and the circular transmission line method (c-TLM) for III-V p-type GaN, respectively. Contacts formed by In/Au to n-type ZnSe and Cu/Au to p-type ZnSe showed the lowest specific contact resistance values of 1.04 x 10--2 Ocm2 and 1.67 x 10--1 Ocm 2, respectively. A nitrogen plasma treatment of the ZnSe surface prior to metallization was proven to lower the contact resistance to p-type ZnSe. Two different current flow mechanisms involving thermionic emission and thermionic field emission were shown for the Cu/Au contact to low doped p-ZnSe (1 x 1017 cm--3) and three involving thermionic emission, thermionic field emission, and tunneling for the Mg/Au contact to highly doped n-ZnSe (1.15 x 1019 cm--3). MOCVD grown p-type Mg-doped GaN with hole concentration of 1.41 x 1017 cm--3 was used to study Ohmic contacts to p-type GaN. The effects of the cryogenic process on improving Ohmic behavior (I-V linearity) and reducing the specific contact resistance were investigated and may result from a combination of the improved surface morphology and the recrystallizing of new compounds such as NiO and Au:Pd solid solution. The I-V-T measurement for both contacts had similar behavior and closely fit thermionic field emission current mechanisms with little deviation but dominant transport mechanisms were not clear since the contacts were practically Ohmic. (Abstract shortened by UMI.)

  8. Chemistry and pharmacology of the piperidine-based analogues of cocaine. Identification of potent DAT inhibitors lacking the tropane skeleton.

    PubMed

    Kozikowski, A P; Araldi, G L; Boja, J; Meil, W M; Johnson, K M; Flippen-Anderson, J L; George, C; Saiah, E

    1998-05-21

    To discover agents that might be useful in the treatment of cocaine abuse, we have chosen to re-explore a class of molecules that was first reported by Clarke et al. in 1973 and that was and shown to lack locomotor stimulatory activity in mice. These compounds are piperidine-3-carboxylic acid esters bearing a 4-chlorophenyl group in position 4, and as such, these structures may be viewed as truncated versions of the WIN series compounds, i.e., they lack the two-carbon bridge of the tropanes. All members of this class were synthesized starting from arecoline hydrobromide and obtained in optically pure form through resolution methods using either (+)- or (-)-dibenzoyltartaric acid. Interestingly, we have found that these piperidines do, in fact, exhibit substantial affinity in both WIN 35, 428 binding at the dopamine transporter and in the inhibition of [3H]dopamine uptake. Of all of the compounds synthesized, the 3-n-propyl derivative (-)-9 was found to be the most potent with a binding affinity of 3 nM. This simple piperidine is thus 33-fold more potent than cocaine in binding affinity and 29-fold more potent in its inhibition of dopamine uptake. Although no efforts have presently been made to "optimize" binding affinity at the DAT, the substantive activity found for the n-propyl derivative (-)-9 is remarkable; the compound is only about 10-fold less active than the best of the high-affinity tropanes of the WIN series. As a further point of interest, it was found that the cis-disubstituted piperidine (-)-3 is only about 2-fold more potent than its trans isomer (+)-11. This result stands in sharp contrast to the data reported for the tropane series, for the epimerization of the substituent at C-2 from beta to alpha has been reported to result in a lowering of activity by 30-200-fold. This smaller spread in binding affinities for the piperidines may reflect the smaller size of these molecules relative to the tropanes, which allows both the cis and the trans isomers to adjust themselves to the binding site on the DAT. Our present demonstration that these piperidine structures do, in fact, possess significant DAT activity, taken together with their reported lack of locomotor activity, provides a compelling argument for exploring this class of molecules further in animal behavioral experiments. The present work thus broadens the scope of structures that may be considered as lead structures in the search for cocaine abuse medications. PMID:9599245

  9. Mechanisms of rolling contact spalling

    NASA Technical Reports Server (NTRS)

    Kumar, A. M.; Kulkarni, S. M.; Bhargava, V.; Hahn, G. T.; Rubin, C. A.

    1987-01-01

    The results of a study aimed at analyzing the mechanical material interactions responsible for rolling contact spalling of the 440 C steel, high pressure oxygen turbopump bearings are presented. A coupled temperature displacement finite element analysis of the effects of friction heating under the contact is presented. The contact is modelled as a stationary, heat generating, 2 dimensional indent in an elastic perfectly plastic half-space with heat fluxes up to 8.6 x 10000 KW/m sq comparable to those generated in the bearing. Local temperatures in excess of 1000 C are treated. The calculations reveal high levels of residual tension after the contact is unloaded and cools. Efforts to promote Mode 2/Mode 3 fatigue crack growth under cyclic torsion in hardened 440 C steel are described. Spalls produced on 440 C steel by a 3 ball/rod rolling contact testing machine were studied with scanning microscopy. The shapes of the cyclic, stress strain hysteresis loops displayed by hardened 440 C steel in cyclic torsion at room temperature are defined for the plastic strain amplitudes encountered in rolling/sliding contact. Results of these analyses are discussed in detail.

  10. The insecticidal neurotoxin Aps III is an atypical knottin peptide that potently blocks insect voltage-gated sodium channels

    PubMed Central

    Bende, Niraj S.; Kang, Eunji; Herzig, Volker; Bosmans, Frank; Nicholson, Graham M.; Mobli, Mehdi; King, Glenn F.

    2013-01-01

    One of the most potent insecticidal venom peptides described to date is Aps III from the venom of the trapdoor spider Apomastus schlingeri. Aps III is highly neurotoxic to lepidopteran crop pests, making it a promising candidate for bioinsecticide development. However, its disulfide-connectivity, three-dimensional structure, and mode of action have not been determined. Here we show that recombinant Aps III (rAps III) is an atypical knottin peptide; three of the disulfide bridges form a classical inhibitor cystine knot motif while the fourth disulfide acts as a molecular staple that restricts the flexibility of an unusually large ? hairpin loop that often houses the pharmacophore in this class of toxins. We demonstrate that the irreversible paralysis induced in insects by rAps III results from a potent block of insect voltage-gated sodium channels. Channel block by rAps III is voltage-independent insofar as it occurs without significant alteration in the voltage-dependence of channel activation or steady-state inactivation. Thus, rAps III appears to be a pore blocker that plugs the outer vestibule of insect voltage-gated sodium channels. This mechanism of action contrasts strikingly with virtually all other sodium channel modulators isolated from spider venoms that act as gating modifiers by interacting with one or more of the four voltage-sensing domains of the channel. PMID:23473802

  11. The insecticidal neurotoxin Aps III is an atypical knottin peptide that potently blocks insect voltage-gated sodium channels.

    PubMed

    Bende, Niraj S; Kang, Eunji; Herzig, Volker; Bosmans, Frank; Nicholson, Graham M; Mobli, Mehdi; King, Glenn F

    2013-05-15

    One of the most potent insecticidal venom peptides described to date is Aps III from the venom of the trapdoor spider Apomastus schlingeri. Aps III is highly neurotoxic to lepidopteran crop pests, making it a promising candidate for bioinsecticide development. However, its disulfide-connectivity, three-dimensional structure, and mode of action have not been determined. Here we show that recombinant Aps III (rAps III) is an atypical knottin peptide; three of the disulfide bridges form a classical inhibitor cystine knot motif while the fourth disulfide acts as a molecular staple that restricts the flexibility of an unusually large ? hairpin loop that often houses the pharmacophore in this class of toxins. We demonstrate that the irreversible paralysis induced in insects by rAps III results from a potent block of insect voltage-gated sodium channels. Channel block by rAps III is voltage-independent insofar as it occurs without significant alteration in the voltage-dependence of channel activation or steady-state inactivation. Thus, rAps III appears to be a pore blocker that plugs the outer vestibule of insect voltage-gated sodium channels. This mechanism of action contrasts strikingly with virtually all other sodium channel modulators isolated from spider venoms that act as gating modifiers by interacting with one or more of the four voltage-sensing domains of the channel. PMID:23473802

  12. Potent antitumor activities of recombinant human PDCD5 protein in combination with chemotherapy drugs in K562 cells

    SciTech Connect

    Shi, Lin [Department of Hematology, The Third Hospital, Peking University, 49 Huayuan North Road, Beijing 100191 (China)] [Department of Hematology, The Third Hospital, Peking University, 49 Huayuan North Road, Beijing 100191 (China); Song, Quansheng; Zhang, Yingmei [Peking University Center for Human Disease Genomics, 38 Xueyuan Road, Beijing 100191 (China) [Peking University Center for Human Disease Genomics, 38 Xueyuan Road, Beijing 100191 (China); Department of Medical Immunology, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191 (China); Lou, Yaxin [Peking University Medical and Health Analysis Center, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191 (China)] [Peking University Medical and Health Analysis Center, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191 (China); Wang, Yanfang [Department of Hematology, The Third Hospital, Peking University, 49 Huayuan North Road, Beijing 100191 (China)] [Department of Hematology, The Third Hospital, Peking University, 49 Huayuan North Road, Beijing 100191 (China); Tian, Linjie; Zheng, Yi; Ma, Dalong [Peking University Center for Human Disease Genomics, 38 Xueyuan Road, Beijing 100191 (China) [Peking University Center for Human Disease Genomics, 38 Xueyuan Road, Beijing 100191 (China); Department of Medical Immunology, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191 (China); Ke, Xiaoyan, E-mail: xiaoyank@yahoo.com [Department of Hematology, The Third Hospital, Peking University, 49 Huayuan North Road, Beijing 100191 (China)] [Department of Hematology, The Third Hospital, Peking University, 49 Huayuan North Road, Beijing 100191 (China); Wang, Ying, E-mail: yw@bjmu.edu.cn [Peking University Center for Human Disease Genomics, 38 Xueyuan Road, Beijing 100191 (China) [Peking University Center for Human Disease Genomics, 38 Xueyuan Road, Beijing 100191 (China); Department of Medical Immunology, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191 (China)

    2010-05-28

    Conventional chemotherapy is still frequently used. Programmed cell death 5 (PDCD5) enhances apoptosis of various tumor cells triggered by certain stimuli and is lowly expressed in leukemic cells from chronic myelogenous leukemia patients. Here, we describe for the first time that recombinant human PDCD5 protein (rhPDCD5) in combination with chemotherapy drugs has potent antitumor effects on chronic myelogenous leukemia K562 cells in vitro and in vivo. The antitumor efficacy of rhPDCD5 protein with chemotherapy drugs, idarubicin (IDR) or cytarabine (Ara-C), was examined in K562 cells in vitro and K562 xenograft tumor models in vivo. rhPDCD5 protein markedly increased the apoptosis rates and decreased the colony-forming capability of K562 cells after the combined treatment with IDR or Ara-C. rhPDCD5 protein by intraperitoneal administration dramatically improved the antitumor effects of IDR treatment in the K562 xenograft model. The tumor sizes and cell proliferation were significantly decreased; and TUNEL positive cells were significantly increased in the combined group with rhPDCD5 protein and IDR treatment compared with single IDR treatment groups. rhPDCD5 protein, in combination with IDR, has potent antitumor effects on chronic myelogenous leukemia K562 cells and may be a novel and promising agent for the treatment of chronic myelogenous leukemia.

  13. Broad and potent HIV-1 neutralization by a human antibody that binds the gp41-gp120 interface.

    PubMed

    Huang, Jinghe; Kang, Byong H; Pancera, Marie; Lee, Jeong Hyun; Tong, Tommy; Feng, Yu; Imamichi, Hiromi; Georgiev, Ivelin S; Chuang, Gwo-Yu; Druz, Aliaksandr; Doria-Rose, Nicole A; Laub, Leo; Sliepen, Kwinten; van Gils, Marit J; de la Peña, Alba Torrents; Derking, Ronald; Klasse, Per-Johan; Migueles, Stephen A; Bailer, Robert T; Alam, Munir; Pugach, Pavel; Haynes, Barton F; Wyatt, Richard T; Sanders, Rogier W; Binley, James M; Ward, Andrew B; Mascola, John R; Kwong, Peter D; Connors, Mark

    2014-11-01

    The isolation of human monoclonal antibodies is providing important insights into the specificities that underlie broad neutralization of HIV-1 (reviewed in ref. 1). Here we report a broad and extremely potent HIV-specific monoclonal antibody, termed 35O22, which binds a novel HIV-1 envelope glycoprotein (Env) epitope. 35O22 neutralized 62% of 181 pseudoviruses with a half-maximum inhibitory concentration (IC50) <50 ?g ml(-1). The median IC50 of neutralized viruses was 0.033 ?g ml(-1), among the most potent thus far described. 35O22 did not bind monomeric forms of Env tested, but did bind the trimeric BG505 SOSIP.664. Mutagenesis and a reconstruction by negative-stain electron microscopy of the Fab in complex with trimer revealed that it bound to a conserved epitope, which stretched across gp120 and gp41. The specificity of 35O22 represents a novel site of vulnerability on HIV Env, which serum analysis indicates to be commonly elicited by natural infection. Binding to this new site of vulnerability may thus be an important complement to current monoclonal-antibody-based approaches to immunotherapies, prophylaxis and vaccine design. PMID:25186731

  14. Crane-Load Contact Sensor

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert; Mata, Carlos; Cox, Robert

    2005-01-01

    An electronic instrument has been developed as a prototype of a portable crane-load contact sensor. Such a sensor could be helpful in an application in which the load rests on a base in a horizontal position determined by vertical alignment pins (see Figure 1). If the crane is not positioned to lift the load precisely vertically, then the load can be expected to swing once it has been lifted clear of the pins. If the load is especially heavy, large, and/or fragile, it could hurt workers and/or damage itself and nearby objects. By indicating whether the load remains in contact with the pins when it has been lifted a fraction of the length of the pins, the crane-load contact sensor helps the crane operator determine whether it is safe to lift the load clear of the pins: If there is contact, then the load is resting against the sides of the pins and, hence, it may not be safe to lift; if contact is occasionally broken, then the load is probably not resting against the pins, so it should be safe to lift. It is assumed that the load and base, or at least the pins and the surfaces of the alignment holes in the load, are electrically conductive, so the instrument can use electrical contact to indicate mechanical contact. However, DC resistance cannot be used as an indicator of contact for the following reasons: The load and the base are both electrically grounded through cables (the load is grounded through the lifting cable of the crane) to prevent discharge of static electricity. In other words, the DC resistance between the load and the pins is always low, as though they were always in direct contact. Therefore, instead of DC resistance, the instrument utilizes the AC electrical impedance between the pins and the load. The signal frequency used in the measurement is high enough (.1 MHz) that the impedance contributed by the cables and the electrical ground network of the building in which the crane and the base are situated is significantly greater than the contact impedance between the pins and the load. The instrument includes a signal generator and voltage-measuring circuitry, and is connected to the load and the base as shown in Figure 2. The output of the signal generator (typically having amplitude of the order of a volt) is applied to the load via a 50-resistor, and the voltage between the load and the pins is measured. When the load and the pins are not in contact, the impedance between them is relatively high, causing the measured voltage to exceed a threshold value. When the load and the pins are in contact, the impedance between them falls to a much lower value, causing the voltage to fall below the threshold value. The voltage-measuring circuitry turns on a red light-emitting diode (LED) to indicate the lower-voltage/ contact condition. Whenever the contact has been broken and the non-contact/higher-voltage condition has lasted for more than 2 ms, the voltage-measuring circuitry indicates this condition by blinking a green LED.

  15. Molecular mechanism of viral resistance to a potent non-nucleoside inhibitor unveiled by molecular simulations.

    PubMed

    Asthana, Shailendra; Shukla, Saumya; Ruggerone, Paolo; Vargiu, Attilio V

    2014-11-11

    Recently, we reported on a potent benzimidazole derivative (227G) that inhibits the growth of the bovine viral diarrhea virus (BVDV) in cell-based and enzyme assays at nanomolar concentrations. The target of 227G is the viral RNA-dependent RNA polymerase (RdRp), and the I261M mutation located in motif I of the RdRp finger domain was found to induce drug resistance. Here we propose a molecular mechanism for the retained functionality of the enzyme in the presence of the inhibitor, on the basis of a thorough computational study of the apo and holo forms of the BVDV RdRp either in the wild type (wt) or in the form carrying the I261M mutation. Our study shows that although the mutation affects to some extent the structure of the apoenzyme, the functional dynamics of the protein appear to be largely maintained, which is consistent with the retained functionality of this natural mutant. Despite the binding site of 227G not collapsing or undergoing drastic structural changes upon introduction of the I261M substitution, these alterations reflect crucially on the binding mode of 227G, which is significantly different from that found in wt RdRp. In particular, while in the wt system the four loops lining the template entrance site embrace 227G and close the template passageway, in the I261M variant the template entrance is only marginally occluded, allowing in principle the translocation of the template to the interior of the enzyme. In addition, the mutated enzyme in the presence of 227G retains several characteristics of the wt apoprotein. Our work provides an original molecular picture of a resistance mechanism that is consistent with published experimental data. PMID:25338932

  16. Structural characterization of more potent alternatives to HAMLET, a tumoricidal complex of ?-lactalbumin and oleic acid.

    PubMed

    Nemashkalova, Ekaterina L; Kazakov, Alexei S; Khasanova, Leysan M; Permyakov, Eugene A; Permyakov, Sergei E

    2013-09-10

    HAMLET is a complex of human ?-lactalbumin (hLA) with oleic acid (OA) that kills various tumor cells and strains of Streptococcus pneumoniae. More potent protein-OA complexes were previously reported for bovine ?-lactalbumin (bLA) and ?-lactoglobulin (bLG), and pike parvalbumin (pPA), and here we explore their structural features. The concentration dependencies of the tryptophan fluorescence of hLA, bLA, and bLG complexes with OA reveal their disintegration at protein concentrations below the micromolar level. Chemical cross-linking experiments provide evidence that association with OA shifts the distribution of oligomeric forms of hLA, bLA, bLG, and pPA toward higher-order oligomers. This effect is confirmed for bLA and bLG using the dynamic light scattering method, while pPA is shown to associate with OA vesicles. Like hLA binding, OA binding increases the affinity of bLG for small unilamellar dipalmitoylphosphatidylcholine vesicles, while pPA efficiently binds to the vesicles irrespective of OA binding. The association of OA with bLG and pPA increases their ?-helix and cross-?-sheet content and resistance to enzymatic proteolysis, which is indicative of OA-induced protein structuring. The lack of excess heat sorption during melting of bLG and pPA in complex with OA and the presence of a cooperative thermal transition at the level of their secondary structure suggest that the OA-bound forms of bLG and pPA lack a fixed tertiary structure but exhibit a continuous thermal transition. Overall, despite marked differences, the HAMLET-like complexes that were studied exhibit a common feature: a tendency toward protein oligomerization. Because OA-induced oligomerization has been reported for other proteins, this phenomenon is inherent to many proteins. PMID:23947814

  17. Contact Phone: Petition to Reinstate Class Schedule

    E-print Network

    Arnold, Jonathan

    Contact Phone: Petition to Reinstate Class Schedule Reinstatement Deadline (September 23, 2014 dropped. Reinstatement Fee: $150.00 STUDENT INFORMATION Academic Term:Student ID # Email Address: Contact

  18. Dermatitis, contact on the cheek (image)

    MedlinePLUS

    ... skin inflammation (dermatitis) on the cheek caused by contact with a substance that produced an allergic reaction (allergen). Contact dermatitis causes redness, itching, and small blisters (vesicles).

  19. Low-resistance and thermally stable ohmic contact on p-type GaN using Pd/Ni metallization

    NASA Astrophysics Data System (ADS)

    Jang, Ho Won; Kim, Ki Hong; Kim, Jong Kyu; Hwang, Soon-Won; Yang, Jung Ja; Lee, Kang Jae; Son, Sung-Jin; Lee, Jong-Lam

    2001-09-01

    We report a low-resistance thermally stable ohmic contact on p-type GaN using a promising contact scheme of Pd/Ni. Specific contact resistance as low as 5.7×10-5 ? cm2 was obtained from the Pd (30 Å)/Ni (70 Å) contact annealed at 500 °C under an oxidizing ambient. NiO that formed at the surface prevented Pd atoms from outdiffusing, promoting the formation of Pd gallides, Ga2Pd5 and Ga5Pd. This reaction produces Ga vacancies below the contact, leading to enhancement of the thermal stability as well as reduction of the contact resistivity.

  20. Low-resistance Pt/Pd/Au ohmic contacts to p-type AlGaN

    NASA Astrophysics Data System (ADS)

    Kim, Han-Ki; Seong, Tae-Yeon; Adesida, Ilesanmi; Tang, Chak Wah; Lau, Kei May

    2004-03-01

    We report on a Pt/Pd/Au metallization scheme for producing low-resistance ohmic contacts to moderately doped p-AlGaN:Mg (1.5×1017 cm-3). Annealed Pt/Pd/Au contact exhibits linear current-voltage characteristics, showing that a high-quality ohmic contact is formed. The Pt/Pd/Au contact exhibits a specific contact resistivity of 3.1×10-4 ? cm2 when annealed at 600 °C for 1 min in a flowing N2 atmosphere. Using Auger electron spectroscopy and x-ray photoelectron spectroscopy, a preliminary explanation for ohmic contact formation is described.