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1

Cytochrome P450-mediated activation of the fragrance compound geraniol forms potent contact allergens  

SciTech Connect

Contact sensitization is caused by low molecular weight compounds which penetrate the skin and bind to protein. In many cases, these compounds are activated to reactive species, either by autoxidation on exposure to air or by metabolic activation in the skin. Geraniol, a widely used fragrance chemical, is considered to be a weak allergen, although its chemical structure does not indicate it to be a contact sensitizer. We have shown that geraniol autoxidizes and forms allergenic oxidation products. In the literature, it is suggested but not shown that geraniol could be metabolically activated to geranial. Previously, a skin-like CYP cocktail consisting of cutaneous CYP isoenzymes, was developed as a model system to study cutaneous metabolism. In the present study, we used this system to investigate CYP-mediated activation of geraniol. In incubations with the skin-like CYP cocktail, geranial, neral, 2,3-epoxygeraniol, 6,7-epoxygeraniol and 6,7-epoxygeranial were identified. Geranial was the main metabolite formed followed by 6,7-epoxygeraniol. The allergenic activities of the identified metabolites were determined in the murine local lymph node assay (LLNA). Geranial, neral and 6,7-epoxygeraniol were shown to be moderate sensitizers, and 6,7-epoxygeranial a strong sensitizer. Of the isoenzymes studied, CYP2B6, CYP1A1 and CYP3A5 showed high activities. It is likely that CYP1A1 and CYP3A5 are mainly responsible for the metabolic activation of geraniol in the skin, as they are expressed constitutively at significantly higher levels than CYP2B6. Thus, geraniol is activated through both autoxidation and metabolism. The allergens geranial and neral are formed via both oxidation mechanisms, thereby playing a large role in the sensitization to geraniol.

Hagvall, Lina [Department of Chemistry, Dermatochemistry and Skin Allergy, University of Gothenburg, SE-412 96 Gothenburg (Sweden); Baron, Jens Malte [Department of Dermatology and Allergology, University Hospital RWTH Aachen, Aachen (Germany); Boerje, Anna [Department of Chemistry, Dermatochemistry and Skin Allergy, University of Gothenburg, SE-412 96 Gothenburg (Sweden); Weidolf, Lars [Discovery DMPK and Bioanalytical Chemistry, AstraZeneca R and D Moelndal, SE-421 83 Moelndal (Sweden); Merk, Hans [Department of Dermatology and Allergology, University Hospital RWTH Aachen, Aachen (Germany); Karlberg, Ann-Therese [Department of Chemistry, Dermatochemistry and Skin Allergy, University of Gothenburg, SE-412 96 Gothenburg (Sweden)], E-mail: karlberg@chem.gu.se

2008-12-01

2

Hydroperoxides in oxidized d -limonene identified as potent contact allergens  

Microsoft Academic Search

Hydroperoxides of d-limonene were shown to be potent contact allergens when studied in guinea-pigs. Limonene-2-hydroperoxide (2-hydroperoxy-p-mentha-6,8-diene, a mixture of trans and cis isomers) was synthesized for the first time. The ratio between the trans and cis forms was 3:1. These two hydroperoxides were identified as the major hydroperoxides in autoxidized d-limonene. In photooxidized d-limonene, they constituted a minor part of

A.-T. Karlberg; L. P. Shao; U. Nilsson; E. GÄfvert; J. L. G. Nilsson

1994-01-01

3

Method for forming metal contacts  

DOEpatents

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.

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

4

Front contact solar cell with formed emitter  

DOEpatents

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.

Cousins, Peter John (Menlo Park, CA)

2012-07-17

5

Front contact solar cell with formed emitter  

DOEpatents

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.

Cousins, Peter John

2014-11-04

6

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

PubMed

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

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

2014-10-01

7

Ink-Jet Printer Forms Solar-Cell Contacts  

NASA Technical Reports Server (NTRS)

Contacts formed in controllable patterns with metal-based inks. System forms upper metal contact patterns on silicon photovoltaic cells. Uses metallo-organic ink, decomposes when heated, leaving behind metallic, electrically conductive residue in printed area.

Alexander, Paul, Jr.; Vest, R. W.; Binford, Don A.; Tweedell, Eric P.

1988-01-01

8

Systemic immunogenicity of para-Phenylenediamine and Diphenylcyclopropenone: two potent contact allergy-inducing haptens.  

PubMed

p-Phenylenediamine (PPD) and Diphenylcyclopropenone (DPCP) are two potent haptens. Both haptens are known to cause delayed-type hypersensitivity, involving a cytokine response and local infiltration of T-cell subpopulations, resulting in contact dermatitis. We investigated the systemic immune effects of PPD and DPCP, two relatively unexplored skin allergens. The dorsal sides of the ears of BALB/c mice were exposed to PPD or DPCP (0.1% w/v or 0.01% w/v), or vehicle alone. Mice were treated once daily for 3 days (induction period) and subsequently twice per week for 8 weeks. Local and systemic immune responses in the auricular and pancreatic lymph nodes, spleen, liver, serum, and ears were analyzed with cytokine profiling MSD, flow cytometry, and qPCR. Ear swelling increased significantly in mice treated with 1% PPD, 0.01% DPCP or 0.1% DPCP, compared with vehicle treatment, indicating that the mice were sensitized and that there was a local inflammation. Auricular lymph nodes, pancreatic lymph nodes, spleen, and liver showed changes in regulatory T-cell, B-cell, and NKT-cell frequencies, and increased activation of CD8(+) T cells and B cells. Intracellular cytokine profiling revealed an increase in the IFN-?- and IL-4-positive NKT cells present in the liver following treatment with both haptens. Moreover, we saw a tendency toward a systemic increase in IL-17A. We observed systemic immunological effects of PPD and DPCP. Furthermore, concentrations too low to increase ear thickness and cause clinical symptoms may still prime the immune system. These systemic immunological effects may potentially predispose individuals to certain diseases. PMID:24385090

Svalgaard, Jesper Dyrendom; Særmark, Carina; Dall, Morten; Buschard, Karsten; Johansen, Jeanne D; Engkilde, Kåre

2014-01-01

9

Novel composite plastics containing silver(i) acylpyrazolonato additives display potent antimicrobial activity by contact.  

PubMed

New silver(I) acylpyrazolonato derivatives displaying a mononuclear, polynuclear, or ionic nature, as a function of the ancillary azole ligands used in the synthesis, have been fully characterized by thermal analysis, solution NMR spectroscopy, solid-state IR and NMR spectroscopies, and X-ray diffraction techniques. These derivatives have been embedded in polyethylene (PE) matrix, and the antimicrobial activity of the composite materials has been tested against three bacterial strains (E.?coli, P.?aeruginosa, and S.?aureus): Most of the composites show antimicrobial action comparable to PE embedded with AgNO3 . Tests by contact and release tests for specific migration of silver from PE composites clearly indicate that, at least in the case of the PE, for composites containing polynuclear silver(I) additives, the antimicrobial action is exerted by contact, without release of silver ions. Moreover, PE composites can be re-used several times, displaying the same antimicrobial activity. Membrane permeabilization studies and induced reactive oxygen species (ROS) generation tests confirm the disorganization of bacterial cell membranes. The cytotoxic effect, evaluated in CD34(+) cells by MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazoliumbromide) and CFU (colony forming units) assays, indicates that the PE composites do not induce cytotoxicity in human cells. Studies of ecotoxicity, based on the test of Daphnia magna, confirm tolerability of the PE composites by higher organisms and exclude the release of Ag(+) ions in sufficient amounts to affect water environment. PMID:25358838

Marchetti, Fabio; Palmucci, Jessica; Pettinari, Claudio; Pettinari, Riccardo; Condello, Francesca; Ferraro, Stefano; Marangoni, Mirko; Crispini, Alessandra; Scuri, Stefania; Grappasonni, Iolanda; Cocchioni, Mario; Nabissi, Massimo; Chierotti, Michele R; Gobetto, Roberto

2015-01-01

10

A reproducing kernel smooth contact formulation for metal forming simulations  

NASA Astrophysics Data System (ADS)

This paper presents a meshfree smooth contact formulation for application to metal forming problems. The continuum-based contact formulation requires continuity in the approximation of contact surface geometry and displacement variables, which is difficult for the conventional finite elements. In this work, we introduce a reproducing kernel approximation to achieve arbitrary degree of smoothness for contact surface representation and displacement field approximation. This approach allows the employment of continuum-based contact formulation, leading to a continuous contact force vector and a consistent tangent particularly advantageous in the Newton iteration of contact analysis. The proposed meshfree smooth contact formulation has been applied to the simulation of metal forming processes and is shown to improve the convergence significantly in comparison with the finite element-based contact formulation.

Wang, Hui-Ping; Wu, Cheng-Tang; Chen, Jiun-Shyan

2014-07-01

11

Method of forming contacts for a back-contact solar cell  

DOEpatents

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.

Manning, Jane

2013-07-23

12

3-Aminopropanal, formed during cerebral ischaemia, is a potent lysosomotropic neurotoxin.  

PubMed

Cytotoxic polyamine-derived amino aldehydes, formed during cerebral ischaemia, damage adjacent tissue (the so-called 'penumbra') not subject to the initial ischaemic insult. One such product is 3-aminopropanal (3-AP), a potent cytotoxin that accumulates in ischaemic brain, although the precise mechanisms responsible for its formation are still unclear. More relevant to the present investigations, the mechanisms by which such a small aldehydic compound might be cytotoxic are also not known, but we hypothesized that 3-AP, having the structure of a weak lysosomotropic base, might concentrate within lysosomes, making these organelles a probable focus of initial toxicity. Indeed, 3-AP leads to lysosomal rupture of D384 glioma cells, a process which clearly precedes caspase activation and apoptotic cell death. Immunohistochemistry reveals that 3-AP concentrates in the lysosomal compartment and prevention of this accumulation by the lysosomotropic base ammonia, NH(3), protects against 3-AP cytotoxicity by increasing lysosomal pH. A thiol compound, N-(2-mercaptopropionyl)glycine, reacts with and neutralizes 3-AP and significantly inhibits cytoxocity. Both amino and aldehyde functions of 3-AP are necessary for toxicity: the amino group confers lysosomotropism and the aldehyde is important for additional, presently unknown, reactions. We conclude that 3-AP exerts its toxic effects by accumulating intralysosomally, causing rupture of these organelles and releasing lysosomal enzymes which initiate caspase activation and apoptosis (or necrosis if the lysosomal rupture is extensive). These results may have implications for the development of new therapeutics designed to lessen secondary damage arising from focal cerebral ischaemia. PMID:12513695

Li, Wei; Yuan, Xi-Ming; Ivanova, Svetlana; Tracey, Kevin J; Eaton, John W; Brunk, Ulf T

2003-04-15

13

3-Aminopropanal, formed during cerebral ischaemia, is a potent lysosomotropic neurotoxin.  

PubMed Central

Cytotoxic polyamine-derived amino aldehydes, formed during cerebral ischaemia, damage adjacent tissue (the so-called 'penumbra') not subject to the initial ischaemic insult. One such product is 3-aminopropanal (3-AP), a potent cytotoxin that accumulates in ischaemic brain, although the precise mechanisms responsible for its formation are still unclear. More relevant to the present investigations, the mechanisms by which such a small aldehydic compound might be cytotoxic are also not known, but we hypothesized that 3-AP, having the structure of a weak lysosomotropic base, might concentrate within lysosomes, making these organelles a probable focus of initial toxicity. Indeed, 3-AP leads to lysosomal rupture of D384 glioma cells, a process which clearly precedes caspase activation and apoptotic cell death. Immunohistochemistry reveals that 3-AP concentrates in the lysosomal compartment and prevention of this accumulation by the lysosomotropic base ammonia, NH(3), protects against 3-AP cytotoxicity by increasing lysosomal pH. A thiol compound, N-(2-mercaptopropionyl)glycine, reacts with and neutralizes 3-AP and significantly inhibits cytoxocity. Both amino and aldehyde functions of 3-AP are necessary for toxicity: the amino group confers lysosomotropism and the aldehyde is important for additional, presently unknown, reactions. We conclude that 3-AP exerts its toxic effects by accumulating intralysosomally, causing rupture of these organelles and releasing lysosomal enzymes which initiate caspase activation and apoptosis (or necrosis if the lysosomal rupture is extensive). These results may have implications for the development of new therapeutics designed to lessen secondary damage arising from focal cerebral ischaemia. PMID:12513695

Li, Wei; Yuan, Xi-Ming; Ivanova, Svetlana; Tracey, Kevin J; Eaton, John W; Brunk, Ulf T

2003-01-01

14

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Information Collection (Accredited Laboratory Contact Update Form) AGENCY: Food Safety and...collection regarding the compilation of updated contact information for Accredited Laboratories...through Friday. FOR FURTHER INFORMATION CONTACT: Contact John O'Connell,...

2013-04-23

15

Method of forming contacts for a back-contact solar cell  

DOEpatents

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.

Manning, Jane

2014-07-15

16

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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...

2010-10-04

17

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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...

2013-09-24

18

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

DOEpatents

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.

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

2013-11-19

19

Contact-spring forming machine for flat conductor cable receptacles  

NASA Technical Reports Server (NTRS)

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.

Angele, W.; Martineck, H. G.

1968-01-01

20

N,N'-Diacetyl-L-cystine-the disulfide dimer of N-acetylcysteine-is a potent modulator of contact sensitivity/delayed type hypersensitivity reactions in rodents.  

PubMed

Oral N-acetyl-L-cysteine (NAC) is used clinically for treatment of chronic obstructive pulmonary disease. NAC is easily oxidized to its disulfide. We show here that N,N'-diacetyl-L-cystine (DiNAC) is a potent modulator of contact sensitivity (CS)/delayed type hypersensitivity (DTH) reactions in rodents. Oral treatment of BALB/c mice with 0.003 to 30 micromol/kg DiNAC leads to enhancement of a CS reaction to oxazolone; DiNAC is 100 to 1000 times more potent than NAC in this respect, indicating that it does not act as a prodrug of NAC. Structure-activity studies suggest that a stereochemically-defined disulfide element is needed for activity. The DiNAC-induced enhancement of the CS reaction is counteracted by simultaneous NAC-treatment; in contrast, the CS reaction is even more enhanced in animals treated with DiNAC together with the glutathione-depleting agent buthionine sulfoximine. These data suggest that DiNAC acts via redox processes. Immunohistochemically, ear specimens from oxazolone-sensitized and -challenged BALB/c mice treated with DiNAC display increased numbers of CD8(+) cells. DiNAC treatment augments the CS reaction also when fluorescein isothiocyanate is used as a sensitizer in BALB/c mice; this is a purported TH2 type of response. However, when dinitrofluorobenzene is used as a sensitizer, inducing a purported TH1 type of response, DiNAC treatment reduces the reaction. Treatment with DiNAC also reduces a DTH footpad-swelling reaction to methylated BSA. Collectively, these data indicate that DiNAC in vivo acts as a potent and effective immunomodulator that can either enhance or reduce the CS or DTH response depending on the experimental conditions. PMID:10027856

Särnstrand, B; Jansson, A H; Matuseviciene, G; Scheynius, A; Pierrou, S; Bergstrand, H

1999-03-01

21

Potent Trypanocidal Curcumin Analogs Bearing a Monoenone Linker Motif Act on Trypanosoma brucei by Forming an Adduct with Trypanothione.  

PubMed

We have previously reported that curcumin analogs with a C7 linker bearing a C4-C5 olefinic linker with a single keto group at C3 (enone linker) display midnanomolar activity against the bloodstream form of Trypanosoma brucei. However, no clear indication of their mechanism of action or superior antiparasitic activity relative to analogs with the original di-ketone curcumin linker was apparent. To further investigate their utility as antiparasitic agents, we compare the cellular effects of curcumin and the enone linker lead compound 1,7-bis(4-hydroxy-3-methoxyphenyl)hept-4-en-3-one (AS-HK014) here. An AS-HK014-resitant line, trypanosomes adapted to AS-HK014 (TA014), was developed by in vitro exposure to the drug. Metabolomic analysis revealed that exposure to AS-HK014, but not curcumin, rapidly depleted glutathione and trypanothione in the wild-type line, although almost all other metabolites were unchanged relative to control. In TA014 cells, thiol levels were similar to untreated wild-type cells and not significantly depleted by AS-HK014. Adducts of AS-HK014 with both glutathione and trypanothione were identified in AS-HK014-exposed wild-type cells and reproduced by chemical reaction. However, adduct accumulation in sensitive cells was much lower than in resistant cells. TA014 cells did not exhibit any changes in sequence or protein levels of glutathione synthetase and ?-glutamylcysteine synthetase relative to wild-type cells. We conclude that monoenone curcuminoids have a different mode of action than curcumin, rapidly and specifically depleting thiol levels in trypanosomes by forming an adduct. This adduct may ultimately be responsible for the highly potent trypanocidal and antiparasitic activity of the monoenone curcuminoids. PMID:25527638

Alkhaldi, Abdulsalam A M; Creek, Darren J; Ibrahim, Hasan; Kim, Dong-Hyun; Quashie, Neils B; Burgess, Karl E; Changtam, Chatchawan; Barrett, Michael P; Suksamrarn, Apichart; de Koning, Harry P

2015-03-01

22

Back contacted and small form factor GAAS solar cell.  

SciTech Connect

We present a newly developed microsystem enabled, back-contacted, shade-free GaAs solar cell. Using microsystem tools, we created sturdy 3 {micro}m thick devices with lateral dimensions of 250 {micro}m, 500 {micro}m, 1 mm, and 2 mm. The fabrication procedure and the results of characterization tests are discussed. The highest efficiency cell had a lateral size of 500 {micro}m and a conversion efficiency of 10%, open circuit voltage of 0.9 V and a current density of 14.9 mA/cm{sup 2} under one-sun illumination.

Clews, Peggy Jane; Wanlass, Mark W. (National Renewable Energy Laboratory); Sanchez, Carlos A.; Pluym, Tammy; Cruz-Campa, Jose Luis; Okandan, Murat; Gupta, Vipin P.; Nielson, Gregory N.; Resnick, Paul James

2010-06-01

23

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

NASA Astrophysics Data System (ADS)

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.

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

2011-05-01

24

Undergraduate* Change of Campus Form *Graduate students should contact the graduate school or their major department.  

E-print Network

or spring semester. Fill out the online Intercampus Enrollment Request form to request one-time enrollment. Who should fill out a change of campus form? Submit a change of campus form to the campus where youUndergraduate* Change of Campus Form *Graduate students should contact the graduate school

Collins, Gary S.

25

Experimental Tooling for Contact Stress Measurement in Bulk Metal Forming Processes  

NASA Astrophysics Data System (ADS)

Knowledge of contact stresses in metal forming operations is essential not only for optimal die design, but also for theoretical and numerical analysis of the metal forming processes. Determination of contact stresses can be performed theoretically and experimentally. This paper presents a tool construction with built-in pin-load cells for experimental determination of contact stresses and friction coefficient at upsetting of prismatic specimen with cylindrical dies. This construction allows measurement of contact stresses in any point of the contact surface of specimen, due to adjustable location of pin-load cells. The adjustments are performed by turning cylindrical dies around its own axis in combination with the change of axial position of the specimen. Experimental determination of contact stresses in upsetting of Ck35 prismatic specimens using cylindrical tools was performed at the Laboratory for technology of plasticity, FTN Novi Sad.

Viloti?, Dragiša; Plan?ak, Miroslav

2011-01-01

26

Atrium Space or Banner Request Form Contact Person  

E-print Network

times (during and after the activity) 4. No profanity or smoking allowed in Atrium or inside Signature (if student club request): Date: Section below to be completed by Associate Dean College complete this form and return to the College of Engineering & Computer Science, Office of the Dean, Bldg

Wu, Shin-Tson

27

Characterization of contact tensions during incremental forming of metal composites  

Microsoft Academic Search

The realization of light weight design of components with local, load adapted properties is a major goal in the development\\u000a of new manufacturing and processing methods of metal composite materials. A main challenge in the manufacturing of compounds\\u000a by forming consists in the realization of the necessary conditions for the initiation of the diffusion process and the generation\\u000a of metallic

R. Neugebauer; S. Meinel; R. Glaß; M. Popp

2010-01-01

28

Method of forming emitters for a back-contact solar cell  

DOEpatents

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.

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

2014-12-16

29

Method or forming emitters for a back-contact solar cell  

DOEpatents

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.

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

2014-08-12

30

FE-Analysis of the Sheet Metal Forming Processes using Continuous Contact Treatment  

SciTech Connect

In general, the sheet metal and die are described by finite elements for the simulation of the metal forming processes. Because the characteristics as continuum of the sheet metal are represented with triangles and rectangles, the errors occur inevitably in finite element analysis. Many contact schemes to describe the deformation modes exactly have been introduced in order to decrease these errors. In this study, a scheme for continuous contact treatment is proposed in order to consider the realistic behavior of contact phenomena during the forming process. The discrete mesh causes stepwise propagation of contact nodes of the sheet even though the contact region of the real forming process is altered very smoothly. It gives rise to convergence problem in case that the process, for example bending process, is sensitive to the contact between the sheet and the tools. For the verification of the proposed method, the compression forming of a tube is simulated and the contact pressures at each integration points are evaluated during deformation of the sheet. The analysis of hemi-spherical punch forming without blank holder is also presented in order to investigate the effects of the proposed algorithm.

Kim, Tae-Jeong; Yang, Dong-Yol [Dept. of Mech. Eng., KAIST, Science Town, Daejeon, 305-701 (Korea, Republic of)

2005-08-05

31

Microsoft Word - App 3-2 Participant Contact Form Specs .doc  

Cancer.gov

Lung Screening Study Version 3.0 Manual of Operations and Procedures 11/15/00 Appendix 3-2 Lung Screening Study Specifications for Completion of the Participant Contact Form (PCF) This form is self-administered. It is to be completed at time

32

Inferring Ideal Amino Acid Interaction Forms From Statistical Protein Contact Potentials  

E-print Network

increasingly heavily used over the last 20 years for ligand docking, fold recognition, and protein structureInferring Ideal Amino Acid Interaction Forms From Statistical Protein Contact Potentials Piotr. Baker Center for Bioinformatics and Biological Statistics, Iowa State University, Ames, Iowa 3 Faculty

Pokarowski, Piotr

33

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

E-print Network

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

Harms, Kyle E.

34

Formulation of Contact Problems in Sheet Metal Forming Simulation Using Local Interpolation for Tool Surfaces  

NASA Astrophysics Data System (ADS)

The treatment of contact between a sheet and tools is one of the most difficult problems to deal with in finite-element simulations of the sheet metal forming processes. In order to obtain more accurate tool models without increasing the number of elements, this paper describes new techniques for the contact problem using a local interpolation for tool surfaces proposed by Nagata. The Nagata patch enables the creation of tool models that are much more accurate in shape than those of the conventional polyhedral representations. Contact search algorithms between the sheet nodes and the interpolated tool surfaces and a consistent contact tangent stiffness matrix for the sliding sheet nodes were formulated. The proposed contact search algorithms allow robust and accurate contact analyses. The developed algorithms were introduced into the static-explicit elastoplastic finite-element method code STAMP3D. Simulations of a square-cup deep-drawing process with a very coarsely discretized punch model were carried out. The simulated results showed that the proposed algorithms yield the proper deformation process, thus demonstrating the validity of the proposed techniques.

Hama, Takayuki; Takamura, Masato; Makinouchi, Akitake; Teodosiu, Cristian; Takuda, Hirohiko

35

The chlamydial organism Simkania negevensis forms ER vacuole contact sites and inhibits ER-stress.  

PubMed

Most intracellular bacterial pathogens reside within membrane-surrounded host-derived vacuoles. Few of these bacteria exploit membranes from the host's endoplasmic reticulum (ER) to form a replicative vacuole. Here, we describe the formation of ER-vacuole contact sites as part of the replicative niche of the chlamydial organism Simkania negevensis. Formation of ER-vacuole contact sites is evolutionary conserved in the distantly related protozoan host Acanthamoeba castellanii. Simkania growth is accompanied by mitochondria associating with the Simkania-containing vacuole (SCV). Super-resolution microscopy as well as 3D reconstruction from electron micrographs of serial ultra-thin sections revealed a single vacuolar system forming extensive ER-SCV contact sites on the Simkania vacuolar surface. Simkania infection induced an ER-stress response, which was later downregulated. Induction of ER-stress with Thapsigargin or Tunicamycin was strongly inhibited in cells infected with Simkania. Inhibition of ER-stress was required for inclusion formation and efficient growth, demonstrating a role of ER-stress in the control of Simkania infection. Thus, Simkania forms extensive ER-SCV contact sites in host species evolutionary as diverse as human and amoeba. Moreover, Simkania is the first bacterial pathogen described to interfere with ER-stress induced signalling to promote infection. PMID:24528559

Mehlitz, Adrian; Karunakaran, Karthika; Herweg, Jo-Ana; Krohne, Georg; van de Linde, Sebastian; Rieck, Elke; Sauer, Markus; Rudel, Thomas

2014-08-01

36

Solar cell with improved N-region contact and method of forming the same  

NASA Technical Reports Server (NTRS)

An improved solar cell, and method of forming the same are disclosed. It is characterized by a semiconductor silicon wafer of P-type material having diffused therein a shallow N-type region. A sintered silver contact is affixed to the surface of the N-type region at the outer surface. The improved solar cell is formulated from silver powder blended with silver metaphosphate for establishing a zone of increased carrier concentration. An aluminum or silver-aluminum alloy contact is affixed to the P-type wafer at the outer surface opposite the N-type region.

Bube, K. R. (inventor)

1979-01-01

37

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

DOEpatents

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.

Cousins, Peter John

2012-06-26

38

Heterodimers of the SnoN and Ski oncoproteins form preferentially over homodimers and are more potent transforming agents.  

PubMed

sno is a member of the ski oncogene family and shares ski 's ability to transform avian fibroblasts and induce muscle differentiation. Ski and SnoN are transcription factors that form both homodimers and heterodimers. They recognize a specific DNA binding site (GTCTAGAC) through which they repress transcription. Efficient homodimerization of Ski, mediated by a bipartite C-terminal domain consisting of five tandem repeats (TR) and a leucine zipper (LZ), correlates with efficient DNA binding and cellular transformation. The present study assesses the role of SnoN homodimerization and SnoN:Ski heterodimerization in the activities of these proteins. Unlike Ski, efficient homodimerization by SnoN is shown to require an upstream region of the protein in addition to the TR/LZ domain. Deletion of the TR/LZ from SnoN decreases its activity in transcriptional repression and cellular transformation. When co-expressed in vitro, c-Ski and SnoN preferentially form heterodimers. In vivo, they form heterodimers that bind the GTCTAGAC element. Tethered Ski:Sno hetero-dimers that lack TR/LZ domains are more active than either their monomeric counterparts, tethered Ski:Ski homodimers or full-length SnoN and c-Ski. This work demonstrates, for the first time, the differences between dimer formation by Ski and SnoN and underscores the importance of dimerization in their activity. PMID:9927733

Cohen, S B; Zheng, G; Heyman, H C; Stavnezer, E

1999-02-15

39

Contacts  

Cancer.gov

Contacts Questions regarding responsiveness of the proposed studies to the BIQSFP should be directed to the one of the following NCI Program Staff: For CTEP:Margaret M. Mooney, M.D.ChiefClinical Investigations BranchNational Cancer Institute9609 Medical

40

Thin film solid-state reactions forming carbides as contact materials for carbon-containing semiconductors  

NASA Astrophysics Data System (ADS)

Metal carbides are good candidates to contact carbon-based semiconductors (SiC, diamond, and carbon nanotubes). Here, we report on an in situ study of carbide formation during the solid-state reaction between thin films. The solid-state reaction was examined between 11 transition metals (W, Mo, Fe, Cr, V, Nb, Mn, Ti, Ta, Zr, and Hf) and an amorphous carbon layer. Capping layers (C or TiN) of different thicknesses were applied to prevent oxidation. Carbide formation is evidenced for nine metals and the phases formed have been identified (for a temperature ranging from 100to1100°C). W first forms W2C and then WC; Mo forms Mo2C; Fe forms Fe3C; Cr first forms metastable phases Cr2C and Cr3C2-x, and finally forms Cr3C2; V forms VCx; Nb transforms into Nb2C followed by NbC; Ti forms TiC; Ta first forms Ta2C and then TaC; and Hf transforms into HfC. The activation energy for the formation of the various carbide phases has been obtained by in situ x-ray diffraction.

Leroy, W. P.; Detavernier, C.; Van Meirhaeghe, R. L.; Lavoie, C.

2007-03-01

41

Effects of varying machine stiffness and contact area in UltraForm Finishing  

NASA Astrophysics Data System (ADS)

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.

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

2013-09-01

42

Non-contact automatic measurement of free-form surface profiles on CNC machines  

NASA Astrophysics Data System (ADS)

This paper describes the work to develop a non-contact type automatic measurement system for any free-form surfaces on a CNC machine tool or a coordinate measuring machine (CMM) and its CAD/CAM integration. A laser probe made by Keyence Co. model LC-2220 was integrated into the CNC machine as the non-contact sensor. A measurement software has been developed for automatic surface tracing of any free-form profile. Data transfer to any commercially available CAD/CAM system for reverse engineering is also available via proper DXF file. Extensive calibration work has been carried out on the systematic accuracy of the laser probe with respect to the color material surface slope and edge detection of the workpiece by the use of a HP5528 laser interferometer system. Having employed the surface painting technique the shape error of the copied object relative to its master piece was found within 30 micrometers which is deemed adequate enough to the mold industry.

Fan, Kuang-Chao; Wen, Kuang-Pu

1993-09-01

43

Open form of syntaxin-1A is a more potent inhibitor than wild-type syntaxin-1A of Kv2.1 channels.  

PubMed

We have shown that SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor) proteins not only participate directly in exocytosis, but also regulate the dominant membrane-repolarizing Kv channels (voltage-gated K+ channels), such as Kv2.1, in pancreatic beta-cells. In a recent report, we demonstrated that WT (wild-type) Syn-1A (syntaxin-1A) inhibits Kv2.1 channel trafficking and gating through binding to the cytoplasmic C-terminus of Kv2.1. During beta-cell exocytosis, Syn-1A converts from a closed form into an open form which reveals its active H3 domain to bind its SNARE partners SNAP-25 (synaptosome-associated protein of 25 kDa) and synaptobrevin. In the present study, we compared the effects of the WT Syn-1A and a mutant open form Syn-1A (L165A, E166A) on Kv2.1 channel trafficking and gating. When co-expressed in HEK-293 cells (human embryonic kidney-293 cells), the open form Syn-1A decreased Kv2.1 current density more than (P<0.05) the WT Syn-1A (166+/-35 and 371+/-93 pA/pF respectively; control=911+/-91 pA/pF). Confocal microscopy and biotinylation experiments showed that both the WT and open form Syn-1A inhibited Kv2.1 expression at the plasma membrane to a similar extent, suggesting that the stronger reduction of Kv2.1 current density by the open form compared with the WT Syn-1A is probably due to a stronger direct inhibition of channel activity. Consistently, dialysis of the recombinant open form Syn-1A protein into Kv2.1-expressing HEK-293 cells caused stronger inhibition of Kv2.1 current amplitude (P<0.05) than the WT Syn-1A protein (73+/-2 and 82+/-3% of the control respectively). We found that the H3 but not H(ABC) domain is the putative active domain of Syn-1A, which bound to and inhibited the Kv2.1 channel. When co-expressed in HEK-293 cells, the open-form Syn-1A slowed down Kv2.1 channel activation (tau=12.3+/-0.8 ms) much more than (P<0.05) WT Syn-1A (tau=7.9+/-0.8 ms; control tau=5.5+/-0.6 ms). In addition, only the open form Syn-1A, but not the WT Syn-1A, caused a significant (P<0.05) left-shift in the steady-state inactivation curve (V(1/2)=33.1+/-1.3 and -29.4+/-1.1 mV respectively; control V(1/2)=-24.8+/-2 mV). The present study therefore indicates that the open form of Syn-1A is more potent than the WT Syn-1A in inhibiting the Kv2.1 channel. Such stronger inhibition by the open form of Syn-1A may limit K+ efflux and thus decelerate membrane repolarization during exocytosis, leading to optimization of insulin release. PMID:15518587

Leung, Yuk M; Kang, Youhou; Xia, Fuzhen; Sheu, Laura; Gao, Xiaodong; Xie, Huanli; Tsushima, Robert G; Gaisano, Herbert Y

2005-04-01

44

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

E-print Network

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

Gruner, Daniel S.

45

Formation of ohmic contacts to p-type diamond using carbide forming metals  

NASA Astrophysics Data System (ADS)

The measurement of the specific contact resistance, rho(sub C), and microstructural analysis at the metal/diamond interface were carried out for diamond with various acceptor concentrations, N(sub A), in order to understand the carrier transport mechanism at the metal/diamond interface. The rho(sub C) measurements were carried out for polycrystalline boron-doped semiconducting diamonds which were prepared by the microwave plasma chemical vapor deposition. The acceptor concentrations, estimated by the boron concentrations measured by secondary ion mass spectroscopy, ranged from 3 x 10(exp 18) to 3 x 10(exp 20)/cu cm. Ti and Mo films, which form carbides with diamond, were deposited on the diamonds using the electron-beam evaporation technique. The rho(sub C) values were measured by the cricular transmission line method before and after annealing at temperatures in the range of 400-600 C. The dependence of the rho(sub C) values on the acceptor concentrations suggested that the dominant transport mechanism was the field-emission for the diamond with N(sub A) around 10(exp 20)/cu cm and the thermionic-field-emission for the diamond with N(sub A) from 3 x 10(exp 18)/cu cm to 4 x 10(exp 19)/cu cm. The rho(sub C) values of the Ti contacts were observed to decrease upon annealing, whereas those of the Mo contacts decreased gradually with increasing annealing temperature. However, the rho(sub C) values of both the Ti and Mo contacts reached at the same value of approximately 1 x 10(exp -6) Ohm sq cm after annealing at 600 C for the diamonds with N(sub A) higher than 10(exp 20)/cu cm. Note that the rho(sub C) values of the Mo contact were extremely stable at high temperatures: the rho(sub C) values did not deteriorate after annealing at 600 C for more than 3 h. The thermally stable molybdenum carbide (alpha-Mo2C) and amorphous layers were observed at the Mo/diamond interface after annealing at 600 C by cross-sectional transmission electron microscopy and x-ray diffraction.

Nakanishi, Jiro; Otsuki, A.; Oku, T.; Ishiwata, O.; Murakami, Masanori

1994-08-01

46

EQUALITY AND DIVERSITY STAFF STARTER FORM This form is to be completed by all new starters. This form can be obtained in an alternative format if required please contact the  

E-print Network

Form SSF EQUALITY AND DIVERSITY STAFF STARTER FORM This form is to be completed by all new starters. This form can be obtained in an alternative format if required ­ please contact the Equality and Diversity Officer. Please RETURN THIS FORM TO the Equality and Diversity Officer. Departmental Administrators please

Henderson, Gideon

47

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)

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.

Vinod, P. Narayanan

2013-10-01

48

Drug resistance profile and biofilm forming potential of Pseudomonas aeruginosa isolated from contact lenses in Karachi-Pakistan  

PubMed Central

Background The contaminated contact lens provides Pseudomonas aeruginosa an ideal site for attachment and biofilm production. Continuous contact of the eye to the biofilm-infested lens can lead to serious ocular diseases, such as keratitis (corneal ulcers). The biofilms also prevent effective penetration of the antibiotics, which increase the chances of antibiotic resistance. Methods For this study, 22 Pseudomonas aeruginosa isolates were obtained from 36 contact lenses and 14 contact lens protective fluid samples. These isolates were tested against eight commonly used antibiotics using Kirby-Bauer disk diffusion method. The biofilm forming potential of these isolates was also evaluated using various qualitative and quantitative techniques. Finally, a relationship between biofilm formation and antibiotic resistance was also examined. Results The isolates of Pseudomonas aeruginosa tested were found resistant to most of the antibiotics tested. Qualitative and quantitative biofilm analysis revealed that most of the isolates exhibited strong biofilm production. The biofilm production was significantly higher in isolates that were multi-drug resistant (p?forming Pseudomonas aeruginosa isolates are mainly involved in contact lens associated infections. This appears to be the first report from Pakistan, which analyzes both antibiotic resistance profile and biofilm forming potential of Pseudomonas aeruginosa isolates from contact lens of the patients with contact lens associated infections. PMID:24134792

2013-01-01

49

Property of Tin Oxide Film Formed on Tin-Plated Connector Contacts  

Microsoft Academic Search

A tin (Sn)-plated surface Is usually covered with tin oxide film such as SnO. The tin oxide film influences greatly contact resistance characteristics. Therefore, it is important to study contact resistance characteristics under low contact load. In this study, a growth law of the oxide film (relationship between film thickness and exposure time) was found for exposure temperature range from

Terutaka Tamai; Yuya Nabeta; Shigeru Sawada; Yasuhiro Hattori

2010-01-01

50

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

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

51

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

PubMed Central

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

2011-01-01

52

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

DOEpatents

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.

Narayan, Jagdish (Knoxville, TN)

1981-01-01

53

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

PubMed

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

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

2015-01-14

54

Edge contacts of graphene formed by using a controlled plasma treatment  

NASA Astrophysics Data System (ADS)

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

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

2014-12-01

55

Request for Animal Transfer for Imaging Completed form is to be forwarded to appropriate contact person at initiating Institute  

E-print Network

Request for Animal Transfer for Imaging Completed form is to be forwarded to appropriate contact Animal Transfer Information: Date of Arrival STRAIN No./Sex DOB Room/Rack/Cage Biohazard No Yes - Explain Protocol # Expiration Date MRI Scan Animal Information: Date of Arrival Strain: Number of Animals: Sex: Age

Krovi, Venkat

56

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

E-print Network

Campus Courtesy Card Order Form Campus Courtesy cards are available to private individuals only. BYU Departments must contact Treasury Services, 801-422-4701, to order gift cards (http://home.byu.edu/webapp/finserve/content/page/Gift_Cards.html). Campus Courtesy cards cost $1.00 each and have a $0.50 balance. Courtesy cards are valid at all Signature

Martinez, Tony R.

57

High-temperature point-contact transistors and Schottky diodes formed on synthetic boron-doped diamond  

Microsoft Academic Search

Point-contact transistors and Schottky diodes have been formed on synthetic boron-doped diamond. This is the first report of diamond transistors that have power gain. Further, the transistors exhibited power gain at 510°C and the Schottky diodes were operational at 700°C.

M. W. Geis; D. D. Rathman; D. J. Ehrlich; R. A. Murphy; W. T. Lindley

1987-01-01

58

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

NASA Astrophysics Data System (ADS)

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.

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

1990-04-01

59

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

NASA Astrophysics Data System (ADS)

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.

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

2009-07-01

60

Lithium fluoride injection layers can form quasi-Ohmic contacts for both holes and electrons  

NASA Astrophysics Data System (ADS)

Thin LiF interlayers are typically used in organic light-emitting diodes to enhance the electron injection. Here, we show that the effective work function of a contact with a LiF interlayer can be either raised or lowered depending on the history of the applied bias. Formation of quasi-Ohmic contacts for both electrons and holes is demonstrated by electroluminescence from symmetric LiF/polymer/LiF diodes in both bias polarities. The origin of the dynamic switching is charging of electrically induced Frenkel defects. The current density-electroluminescence-voltage characteristics can qualitatively be explained. The interpretation is corroborated by unipolar memristive switching and by bias dependent reflection measurements.

Bory, Benjamin F.; Rocha, Paulo R. F.; Janssen, René A. J.; Gomes, Henrique L.; De Leeuw, Dago M.; Meskers, Stefan C. J.

2014-09-01

61

Back-contacted and small form factor GaAs solar cell  

Microsoft Academic Search

We present a newly developed microsystem enabled, back-contacted, shade-free GaAs solar cell. Using microsystem tools, we created sturdy 3 ?m thick devices with lateral dimensions of 250 ?m, 500 ?m, 1 mm, and 2 mm. The fabrication procedure and the results of characterization tests are discussed below. The highest efficiency cell had a lateral size of 500 ?m and a

J. L. Cruz-Campa; G. N. Nielson; M. Okandan; M. W. Wanlass; C. A. Sanchez; P. J. Resnick; P. J. Clews; T. Pluym; V. P. Gupta

2010-01-01

62

Forming and breaking of contacts in jammed granular media by nonlinear acoustic waves  

NASA Astrophysics Data System (ADS)

We investigate the nonlinear response of pulsed sound transmission in weakly compressed granular materials, composed of glass beads and sand. Amplitude and velocity of longitudinal waves are simultaneously measured. We observe that weakly compressed packings can both exhibit strengthening and weakening of the sound velocity and transmission amplitude when excited by high amplitude sound. These effects are due to the changes of the contacts between the particles and although the effective medium theory qualitatively describes these effects it fails to quantitatively account for them.

Wildenberg, S.; Yang, Y.; van Hecke, M.; Jia, X.

2013-06-01

63

Back-contacted and small form factor GaAs solar cell.  

SciTech Connect

We present a newly developed microsystem enabled, back-contacted, shade-free GaAs solar cell. Using microsystem tools, we created sturdy 3 {micro}m thick devices with lateral dimensions of 250 {micro}m, 500 {micro}m, 1 mm, and 2 mm. The fabrication procedure and the results of characterization tests are discussed. The highest efficiency cell had a lateral size of 500 {micro}m and a conversion efficiency of 10%, open circuit voltage of 0.9 V and a current density of 14.9 mA/cm{sup 2} under one-sun illumination.

Clews, Peggy Jane; Wanlass, Mark W. (National Renewable Energy Laboratory, Golden, CO); Sanchez, Carlos A.; Pluym, Tammy; Cruz-Campa, Jose Luis; Okandan, Murat; Gupta, Vipin P.; Nielson, Gregory N.; Resnick, Paul James

2010-07-01

64

Inferring ideal amino acid interaction forms from statistical protein contact potentials.  

PubMed

We have analyzed 29 different published matrices of protein pairwise contact potentials (CPs) between amino acids derived from different sets of proteins, either crystallographic structures taken from the Protein Data Bank (PDB) or computer-generated decoys. Each of the CPs is similar to 1 of the 2 matrices derived in the work of Miyazawa and Jernigan (Proteins 1999;34:49-68). The CP matrices of the first class can be approximated with a correlation of order 0.9 by the formula e(ij) = h(i) + h(j), 1 contact of amino acid pairs within an average protein environment. PMID:15688450

Pokarowski, Piotr; Kloczkowski, Andrzej; Jernigan, Robert L; Kothari, Neha S; Pokarowska, Maria; Kolinski, Andrzej

2005-04-01

65

Modelling thermal contact resistance on glass forming processes with special interface finite elements  

Microsoft Academic Search

The forming process of glass containers is a complex coupled thermal\\/mechanical problem with interaction between the heat\\u000a transfer analysis and the viscous flow of molten glass. The transfer of heat and change of viscosity are fundamental phenomena\\u000a in this process. The changes in temperature influence the very process of heat transfer since the thermal properties of glass\\u000a change with temperature.

José César Sá; Sébastien Grégoire; Philippe Moreau; Dominique Lochegnies

66

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

67

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

NASA Astrophysics Data System (ADS)

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 CuOx 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 CuOx 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.

Gao, Xu; Aikawa, Shinya; Mitoma, Nobuhiko; Lin, Meng-Fang; Kizu, Takio; Nabatame, Toshihide; Tsukagoshi, Kazuhito

2014-07-01

68

Nanosulfur: A Potent Fungicide Against Food Pathogen, Aspergillus niger  

NASA Astrophysics Data System (ADS)

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.

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

2010-10-01

69

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

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.

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

70

POTENT REGULATORS OF METABOLISM  

PubMed Central

Retinoids (vitamin A and its analogs) are highly potent regulators of cell differentiation, cell proliferation, and apoptosis. Because of these activities, retinoids have been most extensively studied in the contexts of embryonic development and of proliferative diseases, especially cancer and skin disease. Recently, there has been considerable new research interest focused on gaining understanding of the roles that retinoids and/or retinoid-related proteins may have in the development of metabolic diseases, primarily obesity, diabetes, and dyslipidemia. This review will summarize recent advances that have been made in these areas, focusing on the role of retinoids in modulating adipogenesis, the roles of retinoids and retinoid-related proteins as signaling molecules linking obesity with the development of type II diabetes, the roles of retinoids in pancreatic ?-cell biology/insulin secretion, and the actions of retinoids in hepatic steatosis. PMID:23281051

Brun, Pierre-Jacques; Yang, Kryscilla Jian Zhang; Lee, Seung-Ah; Yuen, Jason J.; Blaner, William S.

2012-01-01

71

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)

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.

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

2011-12-01

72

DIMETHYLARSINE AND TRIMETHYLARSINE ARE POTENT GENOTOXINS IN VITRO.  

EPA Science Inventory

Dimethylarsine and Trimethylarsine are potent genotoxins in vitro Andrewes, P; Kitchin, KT; and Wallace, KA Abstract The mechanism of arsenic carcinogenesis is unclear. A complicating factor receiving increasing attention is that arsenic is biomethylated to form vari...

73

Direct Observation of Contact Behaviour to Interpret the Pressure Dependence of the Coefficient of Friction in Sheet Metal Forming  

Microsoft Academic Search

In a previous work, for the determination of the relationship between coefficient of friction and contact pressure to be used in the numerical process simulation, the author found experimentally that the coefficient was constant in the lower pressure range, whilst over 0.3 ?, it decreased with increasing pressure. In the present work, a flat tool drawing apparatus which consists of

A. Azushima; H. Kudo

1995-01-01

74

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

PubMed

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

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

2013-12-01

75

Presenilin-1 forms complexes with the cadherin/catenin cell-cell adhesion system and is recruited to intercellular and synaptic contacts.  

PubMed

In MDCK cells, presenilin-1 (PS1) accumulates at intercellular contacts where it colocalizes with components of the cadherin-based adherens junctions. PS1 fragments form complexes with E-cadherin, beta-catenin, and alpha-catenin, all components of adherens junctions. In confluent MDCK cells, PS1 forms complexes with cell surface E-cadherin; disruption of Ca(2+)-dependent cell-cell contacts reduces surface PS1 and the levels of PS1-E-cadherin complexes. PS1 overexpression in human kidney cells enhances cell-cell adhesion. Together, these data show that PS1 incorporates into the cadherin/catenin adhesion system and regulates cell-cell adhesion. PS1 concentrates at intercellular contacts in epithelial tissue; in brain, it forms complexes with both E- and N-cadherin and concentrates at synaptic adhesions. That PS1 is a constituent of the cadherin/catenin complex makes that complex a potential target for PS1 FAD mutations. PMID:10635315

Georgakopoulos, A; Marambaud, P; Efthimiopoulos, S; Shioi, J; Cui, W; Li, H C; Schütte, M; Gordon, R; Holstein, G R; Martinelli, G; Mehta, P; Friedrich, V L; Robakis, N K

1999-12-01

76

The influence of contact conditions on surface reaction layers formed between steel surfaces lubricated by an aviation oil  

Microsoft Academic Search

This study focuses on the influence of load and temperature on the formation and stability of tribo-films for bearing steel on bearing steel contacts lubricated with an aviation oil, EXXON Turbo 2380 (TCP based - tricresyl phosphate) at ambient temperatures. Experiments were carried out on a pin-on-disc (POD) tribometer (with a ball-on-flat geometry) under an average loading rate of 0.17Ns?1

L. Wang; R. J. K. Wood

2007-01-01

77

Durable contact active antimicrobial materials formed by a one-step covalent modification of polyvinyl alcohol, cellulose and glass surfaces.  

PubMed

In this work we have applied a direct covalent linkage of quaternary ammonium salts (QAS) to prepare a series of contact active antimicrobial surfaces based on widely utilized materials. Formation of antimicrobial polyvinyl alcohol (PVA-QAS), cellulose (cellulose-QAS) and glass (glass-QAS) surfaces was achieved by one step synthesis with no auxiliary linkers. The X-ray photoelectron spectroscopy (XPS) revealed tridentate binding mode of the antimicrobial agent. The antimicrobial activity of the prepared materials was tested on Bacillus cereus, Alicyclobacillus acidoterrestris, Escherichia coli and Pseudomonas aeruginosa. Active site density of the modified materials was examined and found to correlate with their antimicrobial activity. Stability studies at different pH values and temperatures confirmed that the linkage of the bioactive moiety to the surface is robust and resistant to a range of pH and temperatures. Prolonged long-term effectiveness of the contact active materials was demonstrated by their repeated usage, without loss of the antimicrobial efficacy. PMID:24012705

Poverenov, Elena; Shemesh, Moshe; Gulino, Antonino; Cristaldi, Domenico A; Zakin, Varda; Yefremov, Tatiana; Granit, Rina

2013-12-01

78

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)

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.

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

2011-06-01

79

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

80

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

Microsoft Academic Search

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

Sucharit Bhakdi; Roswitha Fussle; Jorgen Tranum-Jensen

1981-01-01

81

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

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

82

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

83

Highly potent silver-organoalkoxysilane antimicrobial porous nanomembrane  

PubMed Central

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

2013-01-01

84

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

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

TANAKA, Hiroyuki K. M.; YOKOYAMA, Izumi

2008-01-01

85

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

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

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

2015-01-01

86

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

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??m(2). 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??m(2). 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

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

2015-01-01

87

Platelets, complement, and contact activation: partners in inflammation and thrombosis.  

PubMed

Platelet activation during thrombotic events is closely associated with complement and contact system activation, which in turn leads to inflammation inflammation . Here we review the interactions between activated platelets platelets and the complement and contact activation contact activation systems in clotting blood. Chondroitin sulfate Chondroitin sulfate Chondroitin sulfate A (CS-A), released from alpha granules during platelet activation, is a potent mediator of crosstalk between platelets platelets and the complement system. CS-A activates complement in the fluid phase, generating anaphylatoxins that mediate leukocyte activation. No complement activation seems to occur on the activated platelet surface, but C3 in the form of C3(H(2)O) is bound to the surfaces of activated platelets platelets . This finding is consistent with the strong expression of membrane-bound complement regulators present at the platelet surface. CS-A exposed on the activated platelets platelets is to a certain amount responsible for recruiting soluble regulators to the surface. Platelet-bound C3(H(2)O) acts as a ligand for leukocyte CR1 (CD35), potentially enabling platelet-leukocyte interactions. In addition, platelet activation leads to the activation of contact system enzymes, which are specifically inhibited by antithrombin, rather than by C1INH, as is the case when contact activation contact activation is induced by material surfaces. Thus, in addition to their traditional role as initiators of secondary hemostasis, platelets platelets also act as mediators and regulators of inflammation inflammation in thrombotic events. PMID:21948369

Hamad, Osama A; Bäck, Jennie; Nilsson, Per H; Nilsson, Bo; Ekdahl, Kristina N

2012-01-01

88

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 ...

89

Environmental Health & Safety Department -Chemical Storage and Distribution Facility (CSDF) Use this form if you would like the EH&S Department to ship DOT regulated materials. Contact the Chemical Hygiene  

E-print Network

this form if you would like the EH&S Department to ship DOT regulated materials. Contact the Chemical to be DOT regulated. The CSDF will prepare all packages for Hazmat shipping and your Banner Index account will be charged for packaging materials, labels, customs fee, and shipping costs. Please allow 7-10 business days

90

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,

91

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

92

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

93

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)

94

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

95

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

96

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:

97

Activated human platelets induce factor XIIa-mediated contact activation.  

PubMed

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

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

2010-01-01

98

Noneczematous Contact Dermatitis  

PubMed Central

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

Foti, Caterina; Vestita, Michelangelo; Angelini, Gianni

2013-01-01

99

Structures and mechanism for the design of highly potent glucocorticoids.  

PubMed

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

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

100

Potent inhibition of ribonuclease A by oligo(vinylsulfonic acid).  

PubMed

Ribonuclease A (RNase A) can make multiple contacts with an RNA substrate. In particular, the enzymatic active site and adjacent subsites bind sequential phosphoryl groups in the RNA backbone through Coulombic interactions. Here, oligomers of vinylsulfonic acid (OVS) are shown to be potent inhibitors of RNase A that exploit these interactions. Inhibition is competitive with substrate and has Ki = 11 pm in assays at low salt concentration. The effect of salt concentration on inhibition indicates that nearly eight favorable Coulombic interactions occur in the RNase A.OVS complex. The phosphonic acid and sulfuric acid analogs of OVS are also potent inhibitors although slightly less effective. OVS is also shown to be a contaminant of MES and other buffers that contain sulfonylethyl groups. Oligomers greater than nine units in length can be isolated from commercial MES buffer. Inhibition by contaminating OVS is responsible for the apparent decrease in catalytic activity that has been observed in assays of RNase A at low salt concentration. Thus, OVS is both a useful inhibitor of RNase A and a potential bane to chemists and biochemists who use ethanesulfonic acid buffers. PMID:12649287

Smith, Bryan D; Soellner, Matthew B; Raines, Ronald T

2003-06-01

101

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:

102

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:

103

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:

104

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:

105

Contact electrification  

Microsoft Academic Search

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

J. Lowell; A. C. Rose-Innes

1980-01-01

106

Solar cell contact formation using laser ablation  

DOEpatents

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.

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

2014-07-22

107

Solar cell contact formation using laser ablation  

DOEpatents

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.

Harley, Gabriel; Smith, David; Cousins, Peter

2012-12-04

108

Anilinotriazoles as potent gamma secretase modulators.  

PubMed

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

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

109

Chaenomeles Sinensis: A Potent ?-and ?-Glucosidase Inhibitor  

Microsoft Academic Search

Problem statement: Glycosidase inhibitors are vital sources for the tr eatment of diabetes type II with a special importance in pharmacology, food industry and biotechnology, since for diabetes control, different diets and drugs, especially herb al medicines are recommended in this era. Approach: While screening for the potent natural glycosidase inhibitors, we found the fruits of Chaenomeles sinensis (C. sinensis

Shruti Sancheti; Sandesh Sancheti; Sung-Yum Seo

2009-01-01

110

Electrical contacts to ultrananocrystalline diamond  

NASA Astrophysics Data System (ADS)

The contact behavior of various metals on n-type nitrogen-doped ultrananocrystalline diamond (UNCD) thin films has been investigated. The influences of the following parameters on the current-voltage characteristics of the contacts are presented: (1) electronegativity and work function of various metals, (2) an oxidizing acid surface cleaning step, and (3) oxide formation at the film/contact interface. Near-ideal ohmic contacts are formed in every case, while Schottky barrier contacts prove more elusive. These results counter most work discussed to date on thin diamond films, and are discussed in the context of the unique grain-boundary conductivity mechanism of the nitrogen-doped UNCD.

Gerbi, J. E.; Auciello, O.; Birrell, J.; Gruen, D. M.; Alphenaar, B. W.; Carlisle, J. A.

2003-09-01

111

Contact DCP  

Cancer.gov

Contact the Division of Cancer Prevention U.S. Mail Address: Division of Cancer Prevention National Cancer Institute 9609 Medical Center Drive Bethesda, MD 20892 Commercial Delivery Address: Division of Cancer Prevention National Cancer Institute 9609

112

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.

113

Contact Information  

Cancer.gov

Contact Information If you have questions concerning the Sallie Rosen Kaplan Fellowship, please send an email to kaplanfellowship@mail.nih.gov. You may also write to the following address: Center for Cancer TrainingNational Cancer Institute9609 Medical

114

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

115

Compact contacting device  

NASA Technical Reports Server (NTRS)

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.

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

116

Types of Contact Lenses  

MedlinePLUS

... Contact Lenses Links Report a Problem 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, ...

117

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

NASA Astrophysics Data System (ADS)

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.

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

2014-07-01

118

Tetrahydrogestrinone Is a Potent Androgen and Progestin  

Microsoft Academic Search

Tetrahydrogestrinone (THG) was recently identified as a novel steroid used illicitly to improve athletic performance. Althoughitsstructureiscloselyrelatedtogestrinone,a19-nor progestin, and resembles that of trenbolone, THG was never marketed, so information on its hormonal properties is not known. In this study, we demonstrate that THG is a highly potent androgen and progestin in a yeast-based in vitro bio- assay system expressing human androgen

ALISON K. DEATH; KRISTINE C. Y. MCGRATH; RYMANTAS KAZLAUSKAS; DAVID J. HANDELSMAN

2010-01-01

119

Potent D-Peptide Inhibitors of HIV-1 Entry  

SciTech Connect

During HIV-1 entry, the highly conserved gp41 N-trimer pocket region becomes transiently exposed and vulnerable to inhibition. Using mirror-image phage display and structure-assisted design, we have discovered protease-resistant D-amino acid peptides (D-peptides) that bind the N-trimer pocket with high affinity and potently inhibit viral entry. We also report high-resolution crystal structures of two of these D-peptides in complex with a pocket mimic that suggest sources of their high potency. A trimeric version of one of these peptides is the most potent pocket-specific entry inhibitor yet reported by three orders of magnitude (IC50 = 250 pM). These results are the first demonstration that D-peptides can form specific and high-affinity interactions with natural protein targets and strengthen their promise as therapeutic agents. The D-peptides described here address limitations associated with current L-peptide entry inhibitors and are promising leads for the prevention and treatment of HIV/AIDS.

Welch,B.; VanDemark, A.; Heroux, A.; Hill, C.; Kay, M.

2007-01-01

120

Potent inhibition of tau fibrillization with a multivalent ligand  

SciTech Connect

Small-molecule inhibitors of tau fibrillization are under investigation as tools for interrogating the tau aggregation pathway and as potential therapeutic agents for Alzheimer's disease. Established inhibitors include thiacarbocyanine dyes, which can inhibit recombinant tau fibrillization in the presence of anionic surfactant aggregation inducers. In an effort to increase inhibitory potency, a cyclic bis-thiacarbocyanine molecule containing two thiacarbocyanine moieties was synthesized and characterized with respect to tau fibrillization inhibitory activity by electron microscopy and ligand aggregation state by absorbance spectroscopy. Results showed that the inhibitory activity of the bis-thiacarbocyanine was qualitatively similar to a monomeric cyanine dye, but was more potent with 50% inhibition achieved at {approx}80 nM concentration. At all concentrations tested in aqueous solution, the bis-thiacarbocyanine collapsed to form a closed clamshell structure. However, the presence of tau protein selectively stabilized the open conformation. These results suggest that the inhibitory activity of bis-thiacarbocyanine results from multivalency, and reveal a route to more potent tau aggregation inhibitors.

Honson, Nicolette S.; Jensen, Jordan R. [Center for Molecular Neurobiology, Department of Molecular and Cellular Biochemistry, College of Medicine, Ohio State University, Columbus, OH 43210 (United States); Darby, Michael V. [College of Pharmacy, Ohio State University, Columbus, OH 43210 (United States); Kuret, Jeff [Center for Molecular Neurobiology, Department of Molecular and Cellular Biochemistry, College of Medicine, Ohio State University, Columbus, OH 43210 (United States)], E-mail: kuret.3@osu.edu

2007-11-09

121

Identification of a Potent Endothelium-Derived Angiogenic Factor  

PubMed Central

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

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

122

Design and Synthesis of Imidazopyrimidine Derivatives as Potent iNOS Dimerization Inhibitors.  

PubMed

A series of imidazopyrimidine derivatives with the general formula I was synthesized and identified as potent inhibitors of iNOS dimer formation, a prerequisite for proper functioning of the enzyme. Stille and Negishi coupling reactions were used as key steps to form the carbon-carbon bond connecting the imidazopyrimidine core to the central cycloalkenyl, cycloalkyl and phenyl ring templates. PMID:19966921

Chu, Guo-Hua; Le Bourdonnec, Bertrand; Gu, Minghua; Ajello, Christopher W; Leister, Lara K; Sellitto, Ian; Cassel, Joel A; Tuthill, Paul A; O' Hare, Heather; Dehaven, Robert N; Dolle, Roland E

2009-01-01

123

Design and Synthesis of Imidazopyrimidine Derivatives as Potent iNOS Dimerization Inhibitors  

PubMed Central

A series of imidazopyrimidine derivatives with the general formula I was synthesized and identified as potent inhibitors of iNOS dimer formation, a prerequisite for proper functioning of the enzyme. Stille and Negishi coupling reactions were used as key steps to form the carbon-carbon bond connecting the imidazopyrimidine core to the central cycloalkenyl, cycloalkyl and phenyl ring templates. PMID:19966921

Chu, Guo-Hua; Le Bourdonnec, Bertrand; Gu, Minghua; Ajello, Christopher W; Leister, Lara K; Sellitto, Ian; Cassel, Joel A; Tuthill, Paul A; O’ Hare, Heather; DeHaven, Robert N; Dolle, Roland E

2009-01-01

124

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

E-print Network

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

Hergenrother, Paul J.

125

Formation Of Ohmic Gold Contacts On Epitaxial GaAs  

NASA Technical Reports Server (NTRS)

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.

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

1991-01-01

126

Hemin as a generic and potent protein misfolding inhibitor.  

PubMed

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

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

2014-11-14

127

Contact dermatitis in children  

PubMed Central

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

2010-01-01

128

Flavaglines as potent anticancer and cytoprotective agents.  

PubMed

Flavaglines represent a family of plant natural products that display potent anticancer, cardioprotective, and neuroprotective activities. Novel flavagline derivatives were synthesized and examined for their cytotoxicity on a panel of human cancer cell lines, their cardioprotection against doxorubicin-induced apoptosis in cardiomyocytes, and their neuroprotection in culture models of Parkinson's disease and cisplatin-induced neurotoxicity. The structural requirements of flavaglines for cardio- and neuroprotection were for the first time unraveled and appeared to be slightly different from those for cytotoxicity on cancer cells. We provide also the first evidence that flavaglines may alleviate cisplatin-induced neurotoxicity, suggesting a prophylactic potential of these compounds to prevent this frequently encountered adverse effect of cancer chemotherapies. PMID:23072299

Ribeiro, Nigel; Thuaud, Frédéric; Bernard, Yohann; Gaiddon, Christian; Cresteil, Thierry; Hild, Audrey; Hirsch, Etienne C; Michel, Patrick Pierre; Nebigil, Canan G; Désaubry, Laurent

2012-11-26

129

Allergic contact dermatitis due to a herbicide (barban).  

PubMed Central

Canadian farmers are using increasing amounts of herbicides. Often they do not use adequate skin protection. Two cases of severe allergic contact dermatitis due to the herbicide barban are described. Patch testing with various substances, including barban, confirmed the diagnosis. Sensitization studies in guinea pigs and in one of the authors showed that barban is a potent sensitizer. It is recommended that if skin contact with barban occurs the skin be washed immediately with soap and water. Images Fig. 1 PMID:3971254

Hogan, D J; Lane, P R

1985-01-01

130

CRCHD - PNP Contact  

Cancer.gov

CRCHD - PNP Contact  Back to CRCHD Ongoing Research PNP Contact PNP Contact For questions about the Patient Navigation Programs contact: Roland Garcia, Ph.D.| PNP Project Leader Center to Reduce Cancer Health Disparities National Cancer Institute 6116

131

CRCHD - Contact CNP  

Cancer.gov

CRCHD - Contact CNP  Back to CRCHD Ongoing Research Contact CNP Contact CNP For questions about the Community Networks Program contact: Kenneth Chu, Ph.D.| Chief, Disparities Research Branch, CNP Project Leader 6116 Executive Boulevard Room 602,

132

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

PubMed Central

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

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

133

Semiconductor ohmic contact  

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

134

EDITORIAL: Close contact Close contact  

NASA Astrophysics Data System (ADS)

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

Demming, Anna

2010-07-01

135

Mechanism of Dynamic Contact Line Instability  

NASA Astrophysics Data System (ADS)

Dynamic contact line instability and air entrainment is one of the most limiting problems in liquid coating and other dynamic wetting. It is well known that when the speed of wetting (substrate speed) increases beyond a limit, the originally straight contact line breaks into a sawtooth pattern where thin triangular air films form. The mechanism of this transition is not well understood. In a series of experiments we have found that at the transition point, prior to formation of the sawtooth contact line, a two-dimensional film of air forms while the contact line moves downstream. Immediately after this event, a triangular air stream pattern forms while the contact line remains straight. The contact line then breaks and forms a triangular shape around the triangular air stream. The contact line structure after the transition seems to be driven by the shape of the adjacent air stream. These experiments reveal a mechanism of contact line instability that depends primarily on the air stream pattern and not entirely on the contact line, as previously beleived. This opens the possibility of stability analysis to capture this transition without having to deal with the obstacle of contact line singularity. Supported by NSF grant CTS-9258667.

Aidun, C. K.; Veverka, P. J.

1996-11-01

136

Sifuvirtide, a potent HIV fusion inhibitor peptide  

SciTech Connect

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.

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

137

Solution-Assisted Optical Contacting  

NASA Technical Reports Server (NTRS)

A modified version of a conventional optical-contact procedure has been found to facilitate alignment of optical components. The optical-contact procedure (called simply optical contacting in the art) is a standard means of bonding two highly polished and cleaned glass optical components without using epoxies or other adhesives. In its unmodified form, the procedure does not involve the use of any foreign substances at all: components to be optically contacted are dry. The main disadvantage of conventional optical contacting is that it is difficult or impossible to adjust the alignment of the components once they have become bonded. In the modified version of the procedure, a drop of an alcohol-based optical cleaning solution (isopropyl alcohol or similar) is placed at the interface between two components immediately before putting the components together. The solution forms a weak bond that gradually strengthens during a time interval of the order of tens of seconds as the alcohol evaporates. While the solution is present, the components can be slid, without loss of contact, to perform fine adjustments of their relative positions. After about a minute, most of the alcohol has evaporated and the optical components are rigidly attached to each other. If necessary, more solution can be added to enable resumption or repetition of the adjustment until the components are aligned to the required precision.

Shaddock, Daniel; Abramovici, Alexander

2004-01-01

138

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

139

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

PubMed Central

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

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

140

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

PubMed

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

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

141

Nonlinear Modal Analysis of Mechanical Systems with Frictionless Contact Interfaces  

E-print Network

Nonlinear Modal Analysis of Mechanical Systems with Frictionless Contact Interfaces Denis Laxalde analysis, in the form of nonlinear modes, of mechanical systems undergoing unilateral frictionless contact in contact with a rigid casing is proposed. Sensitivity of the nonlinear modal parameters to contact

Paris-Sud XI, Université de

142

Potent antimicrobial small molecules screened as inhibitors of tyrosine recombinases and Holliday junction-resolving enzymes.  

PubMed

Holliday junctions (HJs) are critical intermediates in many recombination-dependent DNA repair pathways. Our lab has previously identified several hexameric peptides that target HJ intermediates formed in DNA recombination reactions. One of the most potent peptides, WRWYCR, is active as a homodimer and has shown bactericidal activity partly because of its ability to interfere with DNA repair proteins that act upon HJs. To increase the possibility of developing a therapeutic targeting DNA repair, we searched for small molecule inhibitors that were functional surrogates of the peptides. Initial screens of heterocyclic small molecule libraries resulted in the identification of several N-methyl aminocyclic thiourea inhibitors. Like the peptides, these inhibitors trapped HJs formed during recombination reactions in vitro, but were less potent than the peptides in biochemical assays and had little antibacterial activity. In this study, we describe the screening of a second set of libraries containing somewhat larger and more symmetrical scaffolds in an effort to mimic the symmetry of a WRWYCR homodimer and its target. From this screen, we identified several pyrrolidine bis-cyclic guanidine inhibitors that also interfere with processing of HJs in vitro and are potent inhibitors of Gram-negative and especially Gram-positive bacterial growth. These molecules are proof-of-principle of a class of compounds with novel activities, which may in the future be developed into a new class of antibiotics that will expand the available choices for therapy against drug-resistant bacteria. PMID:21938393

Rideout, Marc C; Boldt, Jeffrey L; Vahi-Ferguson, Gabriel; Salamon, Peter; Nefzi, Adel; Ostresh, John M; Giulianotti, Marc; Pinilla, Clemencia; Segall, Anca M

2011-11-01

143

Superstring amplitudes and contact interactions  

Microsoft Academic Search

We show that scattering amplitudes computed from light-cone superstring field theory are divergent at tree level. The divergences can be eliminated, and supersymmetry restored, by the addition of certain counter terms to the light-cone hamiltonian. These counter terms have the form of local contact interactions, whose existence we had previously deduced on grounds of vacuum stability and closure of the

J. Greensite; F. R. Klinkhamer

1988-01-01

144

Statewide Contact Information Columbia College  

E-print Network

://www.westminster-mo.edu/studentlife/chs For further information on wellness issues facing college students, contact: Missouri Partners in Prevention. These problems can take many forms such as depression, anxiety, eating disorders, or stress. Some students about partners in prevention PARTNERS IN PREVENTION (PIP) IS A STATEWIDE COALITION FOCUSED ON PREVENTING

Missouri-Rolla, University of

145

Biological evaluation and molecular modelling study of podophyllotoxin derivatives as potent inhibitors of tubulin polymerization.  

PubMed

Microtubules are considered as important targets of anticancer therapy. Podophyllotoxin and its structural derivative are major microtubule-interfering agents with potent anticancer activity. In this study, we reported the anticancer effects of 10 representative podophyllotoxin derivatives on a panel of four human cancer cell lines. Deoxypodophyllotoxin (6b) and ?-apopicropodophyllotoxin (6g) elicited strong antiproliferative effects (IC??) at a range of 0.0073-0.14 ?M. Direct tubulin depolymerization assay in vitro was also performed. Results showed that that the two compounds can inhibit microtubule polymerization. Experimental measurements were also supported by molecular dynamic simulations, which showed that the two active compounds formed interactions with the colchicine-binding site of the tubulin protein. Our results helped us understand the nature of tubulin binding and determine the core design of a new series of potent inhibitors of tubulin polymerization. PMID:23786349

Ma, Yaqiong; Fang, Senbiao; Li, Huanhuan; Han, Chao; Lu, Yan; Zhao, Yonglong; Liu, Yingqian; Zhao, Chunyan

2013-07-01

146

Pterocarpans and flavanones from Sophora flavescens displaying potent neuraminidase inhibition  

E-print Network

Pterocarpans and flavanones from Sophora flavescens displaying potent neuraminidase inhibition Revised 6 September 2008 Accepted 8 October 2008 Available online 11 October 2008 Keywords: Neuraminidase Sophora flavescens and screened for their ability to inhibit neuraminidase (an enzyme crucial

Lee, Keun Woo

147

Quinoxalinediones: Potent Competitive Non-NMDA Glutamate Receptor Antagonists  

Microsoft Academic Search

The N-methyl-D-aspartate (NMDA)-subtype of glutamate receptors has been well described as a result of the early appearance of NMDA antagonists, but no potent antagonist for the ``non-NMDA'' glutamate receptors has been available. Quinoxalinediones have now been found to be potent and competitive antagonists at non-NMDA glutamate receptors. These compounds will be useful in the determination of the structure-activity relations of

Tage Honore; Steve N. Davies; Jorgen Drejer; Elizabeth J. Fletcher; Poul Jacobsen; David Lodge; Flemming E. Nielsen

1988-01-01

148

Discovery of a Potent And Selective Aurora Kinase Inhibitor  

SciTech Connect

This communication describes the discovery of a novel series of Aurora kinase inhibitors. Key SAR and critical binding elements are discussed. Some of the more advanced analogues potently inhibit cellular proliferation and induce phenotypes consistent with Aurora kinase inhibition. In particular, compound 21 (SNS-314) is a potent and selective Aurora kinase inhibitor that exhibits significant activity in pre-clinical in vivo tumor models.

Oslob, J.D.; Romanowski, M.J.; Allen, D.A.; Baskaran, S.; Bui, M.; Elling, R.A.; Flanagan, W.M.; Fung, A.D.; Hanan, E.J.; Harris, S.; Heumann, S.A.; Hoch, U.; Jacobs, J.W.; Lam, J.; Lawrence, C.E.; McDowell, R.S.; Nannini, M.A.; Shen, W.; Silverman, J.A.; Sopko, M.M.; Tangonan, B.T.

2009-05-21

149

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

NASA Astrophysics Data System (ADS)

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.

Mathews, Daniel

150

A Series of Potent CREBBP Bromodomain Ligands Reveals an Induced-Fit Pocket Stabilized by a Cation–? Interaction**  

PubMed Central

The benzoxazinone and dihydroquinoxalinone fragments were employed as novel acetyl lysine mimics in the development of CREBBP bromodomain ligands. While the benzoxazinone series showed low affinity for the CREBBP bromodomain, expansion of the dihydroquinoxalinone series resulted in the first potent inhibitors of a bromodomain outside the BET family. Structural and computational studies reveal that an internal hydrogen bond stabilizes the protein-bound conformation of the dihydroquinoxalinone series. The side chain of this series binds in an induced-fit pocket forming a cation–? interaction with R1173 of CREBBP. The most potent compound inhibits binding of CREBBP to chromatin in U2OS cells. PMID:24821300

Rooney, Timothy P C; Filippakopoulos, Panagis; Fedorov, Oleg; Picaud, Sarah; Cortopassi, Wilian A; Hay, Duncan A; Martin, Sarah; Tumber, Anthony; Rogers, Catherine M; Philpott, Martin; Wang, Minghua; Thompson, Amber L; Heightman, Tom D; Pryde, David C; Cook, Andrew; Paton, Robert S; Müller, Susanne; Knapp, Stefan; Brennan, Paul E; Conway, Stuart J

2014-01-01

151

Index and Dynamics of Quantized Contact Transformations  

Microsoft Academic Search

Quantized contact transformations are Toeplitz operators over a contact manifold $(X,\\\\alpha)$ of the form $U_{\\\\chi} = \\\\Pi A \\\\chi \\\\Pi$, where $\\\\Pi : H^2(X) \\\\to L^2(X)$ is a Szego projector, where $\\\\chi$ is a contact transformation and where $A$ is a pseudodifferential operator over $X$. They provide a flexible alternative to the Kahler quantization of symplectic maps, and encompass many

Steve Zelditch

2000-01-01

152

Photocatalytic cellulosic electrospun fibers for the degradation of potent cyanobacteria toxin microcystin-LR  

E-print Network

Photocatalytic cellulosic electrospun fibers for the degradation of potent cyanobacteria toxin treatment purposes and tested for photocatalytic decomposition of the potent cyanobacteria toxin microcystin

Steckl, Andrew J.

153

MEDICAL AND EMERGENCY INFORMATION FORM  

E-print Network

MEDICAL AND EMERGENCY INFORMATION FORM Field Trip Name: __________________________ Trip Dates from information about your medical coverage that might be useful. Emergency Contact Information Emergency Personal;___________________________________________________________________________________ Please return completed form to the trip coordinator two weeks prior to departure. Known Medical

Rothman, Daniel

154

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

PubMed

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

Srivastava, Abhishek; Hui, Chung-Yuen

2013-12-01

155

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

PubMed Central

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

Srivastava, Abhishek; Hui, Chung-Yuen

2013-01-01

156

Hydrodynamic lubrication in fully plastic asperity contacts  

NASA Astrophysics Data System (ADS)

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.

Zhang, Yongbin

2012-01-01

157

The Analgesic Activity of Bestatin as a Potent APN Inhibitor  

PubMed Central

Bestatin, a small molecular weight dipeptide, is a potent inhibitor of various aminopeptidases as well as LTA4 hydrolase. Various physiological functions of Bestatin have been identified, viz.: (1) an immunomodifier for enhancing the proliferation of normal human bone marrow granulocyte–macrophage progenitor cells to form CFU-GM colonies; Bestatin exerts a direct stimulating effect on lymphocytes via its fixation on the cell surface and an indirect effect on monocytes via aminopeptidase B inhibition of tuftsin catabolism; (2) an immunorestorator and curative or preventive agent for spontaneous tumor; Bestatin alone or its combination with chemicals can prolongate the disease-free interval and survival period in adult acute or chronic leukemia, therefore, it was primarily marketed in 1987 in Japan as an anticancer drug and servers as the only marketed inhibitor of Aminopeptidase N (APN/CD13) to cure leukemia to date; (3) a pan-hematopoietic stimulator and restorator; Bestatin promotes granulocytopoiesis and thrombocytopoiesis in vitro and restores them in myelo-hypoplastic men; (4) an inhibitor of several natural opioid peptides. Based on the knowledge that APN can cleave several bioactive neuropeptides such as Met-enkaphalins, Leu-enkaphalins, ?-Endorphin, and so on, the anti-aminopeptidase action of Bestatin also allows it to protect endopeptides against their catabolism, exhibiting analgesic activity. Although many scientific studies and great accomplishments have been achieved in this field, a large amount of problems are unsolved. This article reviews the promising results obtained for future development of the analgesic activity of Bestatin that can be of vital interest in a number of severe and chronic pain syndromes. PMID:20631848

Jia, Mei-Rong; Wei, Tao; Xu, Wen-Fang

2010-01-01

158

Cucurbitacins-type triterpene with potent activity on mouse embryonic fibroblast from Cucumis prophetarum, cucurbitaceae  

PubMed Central

Background: Higher plants are considered as a well-known source of the potent anticancer metabolites with diversity of chemical structures. For instance, taxol is an amazing diterpene alkaloid had been lunched since 1990. Objective: To isolate the major compounds from the fruit extract of Cucumis prophetarum, Cucurbitaceae, which are mainly responsible for the bioactivities as anticancer. Materials and Methods: Plant material was shady air dried, extracted with equal volume of chloroform/methanol, and fractionated with different adsorbents. The structures of obtained pure compounds were elucidated with different spectroscopic techniques employing 1D (1H and 13C) and 2D (COSY, HMQC and HMBC) NMR (Nuclear Magnetic Resonance Spectrometry) and ESI-MS (Eelectrospray Ionization Mass Spectrometry) spectroscopy. The pure isolates were tested towards human cancer cell lines, mouse embryonic fibroblast (NIH3T3) and virally transformed form (KA3IT). Results: Two cucurbitacins derivatives, dihydocucurbitacin B (1) and cucurbitacin B (2), had been obtained. Compounds 1 and 2 showed (showed potent inhibitory activities toward NIH3T3 and KA31T with IC50 0.2, 0.15, 2.5 and 2.0 ?g/ml, respectively. Conclusion: The naturally cucurbitacin derivatives (dihydocucurbitacin B and cucurbitacin B) showed potent activities towards NIH3T3 and KA31T, could be considered as a lead of discovering a new anticancer natural drug. PMID:22022168

Ayyad, Seif-Eldin N.; Abdel-Lateff, Ahmed; Basaif, Salim A.; Shier, Thomas

2011-01-01

159

The personal information requested on this form is collected under the authority of Section 33 (c) of the Alberta Freedom of Information and Protection of Privacy Act for the purpose of registering students, contacting students and tracking enrolment stat  

E-print Network

, contacting students and tracking enrolment statistics. Questions concerning the collection, use or disposal of Alberta, Edmonton, AB T5J 4P6. Phone 780.492.5047. LEGAL FIRST NAME LEGAL MIDDLE NAME LEGAL LAST NAME FORMER LAST NAME (if Applicable) DATE OF BIRTH (mm-dd-yyyy) Male Female TELEPHONE Home Cell Work

MacMillan, Andrew

160

Magnetic moment formation in quantum point contacts  

NASA Astrophysics Data System (ADS)

We study the formation of local magnetic moments in quantum point contacts. Using a Hubbard-like model to describe point contacts formed in a two-dimensional system, we calculate the magnetic moment using the unrestricted Hartree approximation. We analyze different type of potentials to define the point contact, for a simple square potential we calculate a phase diagram in the parameter space (Coulomb-repulsion-gate voltage). We also present an analytical calculation of the susceptibility to give explicit conditions for the occurrence of a local moment, we present a simple scaling argument to analyze how the stability of the magnetic moment depends on the point contact dimensions.

Cornaglia, P. S.; Balseiro, C. A.; Avignon, M.

2005-01-01

161

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

PubMed Central

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

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

162

Of Contact Interactions and Colliders  

E-print Network

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.

Sacha Davidson; Sebastien Descotes-Genon; Patrice Verdier

2014-10-17

163

Mixed formulation for frictionless contact problems  

NASA Technical Reports Server (NTRS)

Simple mixed finite element models and a computational precedure are presented for the solution of frictionless contact problems. The analytical formulation is based on a form of Reissner's large rotation theory of the structure with the effects of transverse shear deformation included. The contact conditions are incorporated into the formulation by using a perturbed Lagrangian approach with the fundamental unknowns consisting of the internal forces (stress resultants), the generalized displacements, and the Lagrange multipliers associated with the contact conditions. The element characteristic array are obtained by using a modified form of the two-field Hellinger-Reissner mixed variational principle. The internal forces and the Lagrange multipliers are allowed to be discontinuous at interelement boundaries. The Newton-Raphson iterative scheme is used for the solution of the nonlinear algebraic equations, and the determination of the contact area and the contact pressures.

Noor, Ahmed K.; Kim, Kyun O.

1989-01-01

164

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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...

2011-06-07

165

Chromosomal contact permits transcription between coregulated genes.  

PubMed

Transcription of coregulated genes occurs in the context of long-range chromosomal contacts that form multigene complexes. Such contacts and transcription are lost in knockout studies of transcription factors and structural chromatin proteins. To ask whether chromosomal contacts are required for cotranscription in multigene complexes, we devised a strategy using TALENs to cleave and disrupt gene loops in a well-characterized multigene complex. Monitoring this disruption using RNA FISH and immunofluorescence microscopy revealed that perturbing the site of contact had a direct effect on transcription of other interacting genes. Unexpectedly, this effect on cotranscription was hierarchical, with dominant and subordinate members of the multigene complex engaged in both intra- and interchromosomal contact. This observation reveals the profound influence of these chromosomal contacts on the transcription of coregulated genes in a multigene complex. PMID:24243018

Fanucchi, Stephanie; Shibayama, Youtaro; Burd, Shaun; Weinberg, Marc S; Mhlanga, Musa M

2013-10-24

166

Amorphous Ge bipolar blocking contacts on Ge detectors  

SciTech Connect

Semiconductor nuclear radiation detectors are usually operated in a full depletion mode and blocking contacts are required to maintain low leakage currents and high electric fields for charge collection. Blocking contacts on Ge detectors typically consist of n-type contacts formed by lithium diffusion and p-type contacts formed by boron ion implantation. Electrical contacts formed using sputtered amorphous Ge (a-Ge) films on high-purity Ge crystals were found to exhibit good blocking behavior in both polarities with low leakage currents. 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. Multi-electrode detectors can be fabricated with very simple processing steps using these contacts. 12 refs.

Luke, P.N.; Cork, C.P.; Madden, N.W.; Rossington, C.S.; Wesela, M.F.

1991-10-01

167

Contact Lens Solution Toxicity  

MedlinePLUS

... solutions include: Cleaning solutions Rinsing solutions Disinfecting solutions Multipurpose solutions Rewetting solutions Artificial tear products Who's At Risk A large percentage of contact lens wearers experience reactions to contact lens solutions at ...

168

Buying Contact Lenses  

MedlinePLUS

... Examination date Date patient receives prescription after a contact lens fitting (issue date) and expiration date of prescription Name, address, phone number and fax number of prescriber Power Material and/or manufacturer of the prescribed contact ...

169

Thermal contact resistance  

E-print Network

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 ...

Mikic, B. B.

1966-01-01

170

Cylindrical thermal contact conductance  

E-print Network

temperatures and heat transfer rates. Many situations call for contact heat transfer through nominally cylindrical interfaces, yet relatively few studies of contact conductance through cylindrical interfaces have been undertaken. This study presents a review...

Ayers, George Harold

2004-09-30

171

Irritant Contact Dermatitis  

MedlinePLUS

... by direct chemical injury to the skin. Unlike allergic contact dermatitis, which appears 48–72 hours after exposure to ... Provider May Prescribe References/Trusted Links Related diseases: Allergic Contact Dermatitis Dyshidrotic Eczema (Dyshidrotic Dermatitis) Eczema (Atopic Dermatitis) Erythrasma ...

172

CONTACT URTICARIA: PRESENT SCENARIO  

PubMed Central

Immunological contact urticaria is a hypersensitivity reaction that appears on the skin following contact with an eliciting substance. Recent advances in our understanding of the molecular mechanism and pathogenesis of this reaction have altered its classification, diagnosis, and treatment. We discuss classification, epidemiology, diagnosis, testing, and treatment options that are available to patients with contact urticaria. PMID:20161861

Bhatia, Ruchi; Alikhan, Ali; Maibach, Howard I

2009-01-01

173

Lab Contact: After Hours Phone  

E-print Network

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

Shull, Kenneth R.

174

[Correct contact lens hygiene].  

PubMed

Although contact lenses have long been established in ophthalmology, practical aspects of handling contact lenses is becoming increasingly less important in the clinical training as specialist for ophthalmology. Simultaneously, for many reasons injuries due to wearing contact lenses are increasing. In order to correct this discrepancy, information on contact lenses and practical experience with them must be substantially increased from a medical perspective. This review article deals with the most important aspects for prevention of complications, i.e. contact lens hygiene. PMID:23783996

Blümle, S; Kaercher, T; Khaireddin, R

2013-06-01

175

Contact lens in keratoconus.  

PubMed

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

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

2013-08-01

176

Contact lens in keratoconus  

PubMed Central

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

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

2013-01-01

177

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

PubMed

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

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

2014-01-01

178

Synthesis of tripeptides as potent Yersinia protein tyrosine phosphatase inhibitors  

E-print Network

reserved. Yersinia pestis, a Gram-negative bacillus, is the causa- tive agent of plague.1Synthesis of tripeptides as potent Yersinia protein tyrosine phosphatase inhibitors Kyeong Lee,2 The pathogenicity of Yersinia re- lies on the activity of a bacterial virulence factor called YopH, a eukaryotic

179

Amino-substituted thalidomide analogs: Potent inhibitors of TNF-? production  

Microsoft Academic Search

Thalidomide, (1), is a known inhibitor of TNF-? release in LPS stimulated human PBMC. Herein we describe the TNF-? inhibitory activity of amino substituted analogs of thalidomide (1) and its isoindolin-1-one analog, EM-12 (2). The 4-amino substituted analogs were found to be potent inhibitors of TNF-? release in LPS stimulated human PBMC.

George W. Muller; Roger Chen; Shaei-Yun Huang; Laura G. Corral; Lu Min Wong; Rebecca T. Patterson; Yuxi Chen; Gilla Kaplan; David I. Stirling

1999-01-01

180

Isolation of peptides of the brevinin-1 family with potent  

E-print Network

Isolation of peptides of the brevinin-1 family with potent candidacidal activity from the skin types of antifungal agents. Six peptides with antimicrobial activity were isolated from norepinephrine therapeutic potential for systemic use is limited by its strong hemolytic activity (HC50 ¼ 4 lM). The single

Davidson, Carlos

181

Extensive screening for herbal extracts with potent antioxidant properties  

PubMed Central

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

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

2011-01-01

182

The discovery of potent selective NPY Y(2) antagonists.  

PubMed

A series of small molecules with a piperidinyl core were synthesized and tested for binding affinity (IC50) at human Neuropeptide Y Y2 receptor. Various amide related analogs (ureas, reversed amides, and sulfonamides) were evaluated. Several potent and selective NPY Y2 antagonists were identified. PMID:23756063

Chai, Wenying; Wong, Victoria D; Nepomuceno, Diane; Bonaventure, Pascal; Lovenberg, Timothy W; Carruthers, Nicholas I

2013-07-15

183

Flurbiprofen: A Potent Inhibitor of Alveolar Bone Resorption in Beagles  

Microsoft Academic Search

The nonsteroidal anti-inflammatory drug, flurbiprofen, a potent cyclooxygenase inhibitor, significantly decreases the resorption of alveolar bone in naturally occurring chronic destructive periodontal disease in beagles. This observation indicates that arachidonic acid metabolites are important in the alveolar bone loss of periodontitis and suggests a use for flurbiprofen in the management of bone resorption disease.

R. C. Williams; M. K. Jeffcoat; M. L. Kaplan; P. Goldhaber; H. G. Johnson; W. J. Wechter

1985-01-01

184

Potent Antielastase and Antityrosinase Activities of Astilbe chinensis  

Microsoft Academic Search

Problem statement: In the current scenario, photo-aging is a major pr oblem causing skin wrinkling and hyperpigmentation. Therefore, elastas e and tyrosinase inhibitors play an important role in the treatment of skin aging and thus, gaining a special attention in cosmetic industries. Approach: In the screening of Korean medicinal plants to sea rch the potent elastase and tyrosinase inhibitors, the

Seung-Hun Lee; Sandesh Sancheti; Shruti Sancheti; Sung-Yum Seo

2009-01-01

185

Better Ohmic Contacts For InP Semiconductor Devices  

NASA Technical Reports Server (NTRS)

Four design modifications enable fabrication of improved ohmic contacts on InP-based semiconductor devices. First modification consists of insertion of layer of gold phosphide between n-doped InP and metal or other overlayer of contact material. Second, includes first modification plus use of particular metal overlayer to achieve very low contact resistivities. Third, also involves deposition of Au(2)P(3) interlayer; in addition, refractory metal (W or Ta) deposited to form contact overlayer. In fourth, contact layer of Auln alloy deposited directly on InP. Improved contacts exhibit low electrical resistances and fabricated without exposing devices to destructive predeposition or postdeposition treatments.

Weizer, Victor G.; Fatemi, Navid S.

1995-01-01

186

Contact Symmetries and Hamiltonian Thermodynamics  

E-print Network

In this work we analyze several aspects of the application of contact geometry to thermodynamics. We first investigate the role of gauge transformations and Legendre symmetries in thermodynamics, with respect to both the contact and the metric structures. Then we present a novel mathematical characterization of first order phase transitions as equilibrium processes on the thermodynamic phase space for which the Legendre symmetry is broken. Moreover, using contact Hamiltonian dynamics, we propose a formalism for thermodynamics that resembles the classical Hamiltonian formulation of conservative mechanics. We find out the general functional form for the relevant contact Hamiltonian in thermodynamics and show that it is a measure of the entropy production along thermodynamic processes. Therefore, we use such property to give a precise definition of thermodynamically admissible processes according to the Second Law of thermodynamics. Finally, we also show that we can give an equivalent formulation in terms of the Fisher-Rao metric, in analogy with the Theory of Relativity, where the metric structure defines admissible paths.

A. Bravetti; C. S. Lopez-Monsalvo; F. Nettel

2014-09-25

187

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 ...

188

Composite electric contact materials  

NASA Astrophysics Data System (ADS)

Two-phase composite materials, i.e., a high-melting component combined with a material exhibiting good electrical and thermal properties find a wide range of application for the manufacture of small- and medium-load relays and switches. Composite contacts can be used in air circuit-breakers (W-Ag, Ag-Ni), oil circuit-breakers (W-Cu, Mo-Cn), vacuum-type switches (W-CuSb, CuCr), and also switches operating in an atmosphere of SF sub 6 (W-Cu). Present-day trends aimed at increasing operating reliability and extending the service life of electrical equipment are finding their expression in efforts being made to modify the classical composites with a veiw to imparting new properties to them by suitably changing their composition and structure. These trends are also aimed at reducing the consumption of noble metals and of strategically important ones. Modern materials engineering and metallurgical technologies are being used, including isostatic sintering or explosive forming. Owing to the high activity of the constituents, all processes are conducted under high vacuum or in pure reducing atmospheres.

Senkara, J.; Kowalczyk, J.

1985-12-01

189

Optical contact micrometer  

DOEpatents

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.

Jacobson, Steven D.

2014-08-19

190

TIGER FUND REQUEST FORM Organization Name  

E-print Network

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

Bogaerts, Steven

191

Specific contact resistance of the porous silicon and silver metal Ohmic contact structure  

NASA Astrophysics Data System (ADS)

We report the experimental result of the specific contact resistance (?c) of porous silicon and silver metal Ohmic contact structure formed on the n+ region (doped with phosphorous atoms) to boron-doped p-type single crystalline silicon. The contact structure consists of sintered Ag metal grid contact on a porous silicon surface, which was formed on the n+ region by an electrochemical etching process. The electrical properties of the Ohmic contact thus formed are estimated by measuring the specific contact resistance at the interface of the porous silicon/silver Ohmic contact structure as a function of surface doping concentration. The measured value of ?c as a function of the surface doping shows that ?c is a strong function of surface doping, and decreases with increasing doping. The measured data provide reliable values of ?c for the silver metal/porous silicon/p-type c-Si structure, which enable us to study the electrical properties of the porous silicon/silver Ohmic contact.

Vinod, P. N.

2005-09-01

192

Relaxation damping in oscillating contacts  

E-print Network

If a contact of two purely elastic bodies with no sliding (infinite coefficient of friction) is subjected to superimposed oscillations in the normal and tangential directions, then a specific damping appears, that is not dependent on friction or dissipation in the material. We call this effect "relaxation damping". The rate of energy dissipation due to relaxation damping is calculated in a closed analytic form for arbitrary axially-symmetric contacts. In the case of equal frequency of normal and tangential oscillations, the dissipated energy per cycle is proportional to the square of the amplitude of tangential oscillation and to the absolute value of the amplitude of normal oscillation, and is dependent on the phase shift between both oscillations. In the case of low frequency tangential motion with superimposed high frequency normal oscillations, the system acts as a tunable linear damper. Generalization of the results for macroscopically planar, randomly rough surfaces is discussed.

M. Popov; V. L. Popov; R. Pohrt

2014-10-13

193

Contact force identification using the subharmonic resonance of a contact-mode atomic force microscopy.  

PubMed

We propose a step-by-step experimental procedure for characterization of the nonlinear contact stiffness on surfaces using contact-mode atomic force microscopy. Our approach directly estimates the first-, second-, and third-order coefficients of the contact stiffness. It neither uses nor requires the underlying assumptions of the Hertzian contact theory. We use a primary resonance excitation of the probe to estimate the linear coefficient of the contact stiffness. We use the method of multiple scales to obtain closed-form expressions approximating the response of the probe to a subharmonic resonance excitation of order one-half. We utilize these expressions and higher-order spectral measurements to independently estimate the quadratic and cubic coefficients of the contact stiffness. PMID:21727423

Abdel-Rahman, Eihab M; Nayfeh, Ali H

2005-02-01

194

Potent Urea and Carbamate Inhibitors of Soluble Epoxide Hydrolases  

NASA Astrophysics Data System (ADS)

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 of trans-stilbene oxide, which is active as the epoxide, but reduce cytotoxicity of leukotoxin, which is activated by epoxide hydrolase to its toxic diol. They also reduce toxicity of leukotoxin in vivo in mice and prevent symptoms suggestive of acute respiratory distress syndrome. These potent inhibitors may be valuable tools for testing hypotheses of involvement of diol and epoxide lipids in chemical mediation in vitro or in vivo systems.

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

1999-08-01

195

Anilino-monoindolylmaleimides as potent and selective JAK3 inhibitors.  

PubMed

We designed a series of anilino-indoylmaleimides based on structural elements from literature JAK3 inhibitors 3 and 4, and our lead 5. These new compounds were tested as inhibitors of JAKs 1, 2 and 3 and TYK2 for therapeutic intervention in rheumatoid arthritis (RA). Our requirements, based on current scientific rationale for optimum efficacy against RA with reduced side effects, was for potent, mixed JAK1 and 3 inhibition, and selectivity over JAK2. Our efforts yielded a potent JAK3 inhibitor 11d and its eutomer 11e. These compounds were highly selective for inhibition of JAK3 over JAK2 and TYK. The compounds displayed only modest JAK1 inhibition. PMID:24461299

McDonnell, Mark E; Bian, Haiyan; Wrobel, Jay; Smith, Garry R; Liang, Shuguang; Ma, Haiching; Reitz, Allen B

2014-02-15

196

Identification of potent inhibitors of the chicken soluble epoxide hydrolase.  

PubMed

In vertebrates, soluble epoxide hydrolase (sEH) hydrolyzes natural epoxy-fatty acids (EpFAs), which are chemical mediators modulating inflammation, pain, and angiogenesis. Chick embryos are used to study angiogenesis, particularly its role in cardiovascular biology and pathology. To find potent and bio-stable inhibitors of the chicken sEH (chxEH) a library of human sEH inhibitors was screened. Derivatives of 1(adamantan-1-yl)-3-(trans-4-phenoxycyclohexyl) urea were found to be very potent tight binding inhibitors (KI <150pM) of chxEH while being relatively stable in chicken liver microsomes, suggesting their usefulness to study the role of EpFAs in chickens. PMID:25479771

Shihadih, Diyala S; Harris, Todd R; Yang, Jun; Merzlikin, Oleg; Lee, Kin Sing S; Hammock, Bruce D; Morisseau, Christophe

2015-01-15

197

UNC1062, a new and potent Mer inhibitor  

PubMed Central

Abnormal activation of Mer kinase has been implicated in the oncogenesis of many human cancers including acute lymphoblastic and myeloid leukemia, non-small cell lung cancer, and glioblastoma. We have discovered a new family of small molecule Mer inhibitors, pyrazolopyrimidine sulfonamides, that potently inhibit the kinase activity of Mer. Importantly, these compounds do not demonstrate significant hERG activity in the PatchXpress assay. Through structure-activity relationship studies, 35 (UNC1062) was identified as a potent (IC50 = 1.1 nM) and selective Mer inhibitor. When applied to live tumor cells, UNC1062 inhibited Mer phosphorylation and colony formation in soft agar. Given the potential of Mer as a therapeutic target, UNC1062 is a promising candidate for further drug development. PMID:23693152

Liu, Jing; Zhang, Weihe; Stashko, Michael A; DeRyckere, Deborah; Cummings, Christopher T.; Hunter, Debra; Yang, Chao; Jayakody, Chatura N.; Cheng, Nancy; Simpson, Catherine; Norris-Drouin, Jacqueline; Sather, Susan; Kireev, Dmitri; Janzen, William P.; Earp, H Shelton; Graham, Douglas K.; Frye, Stephen V.; Wang, Xiaodong

2013-01-01

198

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

PubMed Central

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

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

199

Potent Urea and Carbamate Inhibitors of Soluble Epoxide Hydrolases  

Microsoft Academic Search

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

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

1999-01-01

200

Highly Potent, Chemically Stable Quorum Sensing Agonists for Vibrio Cholerae.  

PubMed

In the Vibrio cholerae pathogen, initiation of bacterial quorum sensing pathways serves to suppress virulence. We describe herein a potent and chemically stable small molecule agonist of V. cholerae quorum sensing, which was identified through rational drug design based on the native quorum sensing signal. This novel agonist may serve as a useful lead compound for the control of virulence in V. cholerae. PMID:24436778

Perez, Lark J; Karagounis, Theodora K; Hurley, Amanda; Bassler, Bonnie L; Semmelhack, Martin F

2014-01-01

201

AMG 837: A Potent, Orally Bioavailable GPR40 Agonist  

Microsoft Academic Search

The discovery that certain long chain fatty acids potentiate glucose stimulated insulin secretion through the previously orphan receptor GPR40 sparked interest in GPR40 agonists as potential antidiabetic agents. Optimization of a series of ?-substituted phenylpropanoic acids led to the identification of (S)-3-(4-((4’-(trifluoromethyl)biphenyl-3-yl)methoxy)phenyl)hex-4-ynoic acid (AMG 837) as a potent GPR40 agonist with a superior pharmacokinetic profile and robust glucose-dependent stimulation of

Jonathan B. Houze; Liusheng Zhu; Ying Sun; Michelle Akerman; Wei Qiu; Alex J. Zhang; Rajiv Sharma; Michael Schmitt; Yingcai Wang; Jiwen Liu; Jinqian Liu; Julio C. Medina; Jeff D. Reagan; Jian Luo; George Tonn; Jane Zhang; Jenny Ying-Lin Lu; Michael Chen; Edwin Lopez; Kathy Nguyen; Li Yang; Liang Tang; Hui Tian; Steven J. Shuttleworth; Daniel C.-H. Lin

202

Astaxanthin and canthaxanthin are potent antioxidants in a membrane model.  

PubMed

When the conjugated keto-carotenoids, either astaxanthin or canthaxanthin, are added to rat liver microsomes undergoing radical-initiated lipid peroxidation under air, they are as effective as alpha-tocopherol in inhibiting this process. This contrasts with the effect of beta-carotene, which is a much less potent antioxidant when added in this system, without the addition of other antioxidants. PMID:1497349

Palozza, P; Krinsky, N I

1992-09-01

203

Amphibian glucagon family peptides: potent metabolic regulators in fish hepatocytes  

Microsoft Academic Search

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

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

2001-01-01

204

A novel potent vasoconstrictor peptide produced by vascular endothelial cells  

Microsoft Academic Search

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

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

1988-01-01

205

Diversity Against Adversity: How Adaptive Immune System Evolves Potent Antibodies  

NASA Astrophysics Data System (ADS)

Adaptive immunity is an amazing mechanism, whereby new protein functions—affinity of antibodies (Immunoglobulins) to new antigens—evolve through mutation and selection in a matter of a few days. Despite numerous experimental studies, the fundamental physical principles underlying immune response are still poorly understood. In considerable departure from past approaches, here, we propose a microscopic multiscale model of adaptive immune response, which consists of three essential players: The host cells, viruses, and B-cells in Germinal Centers (GC). Each moiety carries a genome, which encodes proteins whose stability and interactions are determined from their sequences using laws of Statistical Mechanics, providing an exact relationship between genomic sequences and strength of interactions between pathogens and antibodies and antibodies and host proteins (autoimmunity). We find that evolution of potent antibodies (the process known as Affinity Maturation (AM)) is a delicate balancing act, which has to reconcile the conflicting requirements of protein stability, lack of autoimmunity, and high affinity of antibodies to incoming antigens. This becomes possible only when antibody producing B cells elevate their mutation rates (process known as Somatic Hypermutation (SHM)) to fall into a certain range—not too low to find potency increasing mutations but not too high to destroy stable Immunoglobulins and/or already achieved affinity. Potent antibodies develop through clonal expansion of initial B cells expressing marginally potent antibodies followed by their subsequent affinity maturation through mutation and selection. As a result, in each GC the population of mature potent Immunoglobulins is monoclonal being ancestors of a single cell from initial (germline) pool. We developed a simple analytical theory, which provides further rationale to our findings. The model and theory reveal the molecular factors that determine the efficiency of affinity maturation, thereby providing insight into the variability of the immune response to cytopathic viruses (the direct response by germline antibodies) and poorly cytopathic viruses (a crucial role of SHM in the response).

Heo, Muyoung; Zeldovich, Konstantin B.; Shakhnovich, Eugene I.

2011-07-01

206

Shear strength of metal-sapphire contacts  

NASA Technical Reports Server (NTRS)

The shear strength of polycrystalline Ag, Cu, Ni, and Fe contacts on clean (0001) sapphire has been studied in ultrahigh vacuum. Both clean metal surfaces and surfaces exposed to O2, Cl2, and C2H4 were used. The results indicate that there are two sources of strength of Al2O3-metal contacts: an intrinsic one that depends on the particular clean metal in contact with Al2O3 and an additional one due to intermediate films. The shear strength of the clean metal contacts correlated directly with the free energy of oxide formation for the lowest metal oxide, in accord with the hypothesis that a chemical bond is formed between metal cations and oxygen anions in the sapphire surface. Contacts formed by metals exposed to chlorine exhibited uniformly low shear strength indicative of van der Waals bonding between chlorinated metal surfaces and sapphire. Contacts formed by metals exposed to oxygen exhibited enhanced shear strength, in accord with the hypothesis that an intermediate oxide layer increases interfacial strength.

Pepper, S. V.

1976-01-01

207

OMEGA AND BIASING FROM OPTICAL GALAXIES VERSUS POTENT MASS  

E-print Network

The mass density field in the local universe, recovered by the POTENT method from peculiar velocities of $\\sim$3000 galaxies, is compared with the density field of optically-selected galaxies. Both density fields are smoothed with a Gaussian filter of radius 12 $h^{-1}$ Mpc. Under the assumptions of gravitational instability and a linear biasing parameter $b\\sbo$ between optical galaxies and mass, we obtain $\\beta\\sbo \\equiv \\om^{0.6}/b\\sbo = 0.74 \\pm 0.13$. This result is obtained from a regression of POTENT mass density on optical density after correcting the mass density field for systematic biases in the velocity data and POTENT method. The error quoted is just the $1\\sigma$ formal error estimated from the observed scatter in the density--density scatterplot; it does not include the uncertainty due to cosmic scatter in the mean density or in the biasing relation. We do not attempt a formal analysis of the goodness of fit, but the scatter about the fit is consistent with our estimates of the uncertainties.

M. J. Hudson; A. Dekel; S. Courteau; S. M. Faber; J. A. Willick

1995-01-19

208

Omega and biasing from optical galaxies vs. potent mass  

E-print Network

The mass density field in the local universe, recovered by the POTENT method from peculiar velocities of \\sim3000 galaxies, is compared with the density field of optically-selected galaxies. Both density fields are smoothed with a Gaussian filter of radius 12 h^{-1} Mpc. Under the assumptions of gravitational instability and a linear biasing parameter b\\sbo between optical galaxies and mass, we obtain \\beta\\sbo \\equiv \\om^{0.6}/b\\sbo = 0.74 \\pm 0.13. This result is obtained from a regression of POTENT mass density on optical density after correcting the mass density field for systematic biases in the velocity data and POTENT method. The error quoted is just the 1\\sigma formal error estimated from the observed scatter in the density--density scatterplot; it does not include the uncertainty due to cosmic scatter in the mean density or in the biasing relation. We do not attempt a formal analysis of the goodness of fit, but the scatter about the fit is consistent with our estimates of the uncertainties.

Hudson, M J; Courteau, S; Faber, S M; Willick, J A; Hudson, M J; Dekel, A; Courteau, S; Faber, S M; Willick, J A

1995-01-01

209

Please note: If you are interested in forming a nonprofit or applying for tax exempt status, please do not complete this application but contact 313-577-9429 or buscomlaw@wayne.edu for additional information.  

E-print Network

Identification Number? 12. Do you have an Employee Identification Number? No Yes If no, will you need help filing Preparation of application for recognition of federal tax exemption Loan application and closing contractPlease note: If you are interested in forming a nonprofit or applying for tax exempt status, please

VandeVord, Pamela

210

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

-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

Yates, Andrew

211

ACCELERATED COMMUNICATION Di(2-ethylhexyl) phthalate Is a Highly Potent Agonist for the  

E-print Network

ACCELERATED COMMUNICATION Di(2-ethylhexyl) phthalate Is a Highly Potent Agonist for the Human the common plasticizer, di(2- ethylhexyl) phthalate (DEHP), as a highly potent and uniquely selective agonist

Omiecinski, Curtis

212

Discovery of a Potent and Orally Bioavailable CCR2 and CCR5 Dual Antagonist  

PubMed Central

This report describes the discovery of a potent, orally bioavailable CC chemokine receptor 2 (CCR2) antagonist which, while optimized for CCR2 potency, also had potent CC chemokine receptor 5 (CCR5) activity.

2009-01-01

213

Hertzian contact Lamb wave sensors  

NASA Astrophysics Data System (ADS)

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.

Degertekin, Fahrettin Levent

1997-08-01

214

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 R25E Award, contact: Dr. Jeannette KorczakProgram directorE-mail: korczakj@mail.nih.gov Branch

215

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Updated: May 28, 2013 Updated: May 28, 2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application, contact: Dr. Sonia B. JakowlewProgram DirectorE-mail: jakowles@mail.nih.gov Branch Telephone:

216

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217

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218

NCI Staff Contacts  

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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

219

NCI Staff Contacts  

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220

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221

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222

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223

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Updated: May 28, 2013 Updated: May 28, 2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application, contact: Dr. Mark DamicoProgram DirectorE-mail: damicomw@mail.nih.gov Branch Telephone: (240)

224

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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 T32 Award, contact: Dr. Mark DamicoProgram DirectorE-mail: damicomw@mail.nih.gov Dr.

225

NCI Staff Contacts  

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226

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227

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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 K23 Award, contact: Dr. Susan LimProgram DirectorE-mail: lims@mail.nih.gov Branch Phone:

228

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

229

Language Contact: An Introduction.  

ERIC Educational Resources Information Center

This book surveys situations in which language contact arises and focuses on what happens to the languages themselves: sometimes nothing, sometimes the incorporation of new words, sometimes the spread of new sounds and sentence structures across many languages and wide swathes of territory. It outlines the origins and results of contact-induced…

Thomason, Sarah G.

230

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Cancer.gov

NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K18 Award, contact: Dr. Sonia B. JakowlewProgram DirectorTelephone: (301) 496-8580Fax: (301) 480-1744E-mail: jakowles@mail.nih.gov For

231

NCI Staff Contacts  

Cancer.gov

NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application, contact: Dr. Sonia B. JakowlewProgram DirectorTelephone: (240) 276-5630Fax: (240) 276-5659E-mail: jakowles@mail.nih.gov For information regarding

232

NCI Staff Contacts  

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NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K25 Award, contact: Dr. Sonia B. JakowlewProgram DirectorTelephone: (301) 496-8580Fax: (301) 480-1744E-mail: jakowles@mail.nih.gov For

233

NCI Staff Contacts  

Cancer.gov

NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K01 Award, contact: Ms. Nancy C. Lohrey, M.S., MT-ASCPProgram DirectorTelephone: (301) 496-8580Fax: (301) 480-1744E-mail: Lohreyn@mail.nih.gov For

234

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

235

Systemic contact dermatitis.  

PubMed

Systemic contact dermatitis is an inflammatory skin disease that may occur in persons with contact allergy when they are exposed to the hapten orally, transcutaneously, per rectum, intravesically, intravenously, or by inhalation. The most common causes of systemic contact dermatitis are drugs used both topically and systemically. Other causes are ubiquitously occurring haptens, such as the metals nickel, cobalt, gold, and chromate, and aromatic substances such as spices. Avoidance of the offending hapten is the most obvious treatment. For some haptens, such as nickel, diet treatment may be effective. Chelation therapy with disulfiram is another therapeutic option in nickel-allergic patients with systemic contact dermatitis. Hyposensitization therapy has been attempted with some success in systemic contact dermatitis caused by nickel and Parthenium hysterophorus. PMID:22097987

Veien, Niels K

2011-12-01

236

Multivalent Antibiotics via Metal Complexes: Potent Divalent Vancomycins against Vancomycin-Resistant Enterococci  

E-print Network

Multivalent Antibiotics via Metal Complexes: Potent Divalent Vancomycins against Vancomycin, Hong Kong, China, Center of Infection and Department of Microbiology, Faculty of Medicine by a rigid metal complex, [Pt(en)(H2O)2]2+ , exhibit potent activities (MIC 0.8 µg/mL, 720 times more potent

Xing, Bengang

237

Mixed complexes formed by lithioacetonitrile and chiral lithium amides: observation of (6)li,(15)N and (6)Li,(13)C couplings due to both C-Li and N-Li contacts.  

PubMed

NMR spectroscopic studies have been performed on the mixed complexes formed by the lithium salt of acetonitrile (LiCH(2)CN) and the chiral lithium amides Li-(S)-N-(2-methoxybenzyl)-1-amino-1-phenyl-2-ethoxyethane (Li-1) and Li-(S)-N-isopropyl-2-amino-1-phenyl-3-methoxypropane (Li-2) in diethyl ether and tetrahydrofuran solvent. In diethyl ether Li-1 and LiCH(2)CN form a mixed dimeric (1:1) complex, while Li-2 and LiCH(2)CN form a mixed trimeric (2:1) complex. The dimer undergoes fast exchange between ketenimine and bridged structures. Both (1)J((15)N,(6)Li) and (1)J((13)C,(6)Li) couplings were observed for the respectively isotopically labeled compounds. In the trimeric complex the CH(2)CN anion also undergoes fast degenerate exchange between ketenimine and bridged structures, and the complex appears C(2)-symmetric on the NMR spectroscopy time scale. Both the dimer and trimer complexes have the bridged acetonitrile anion in common, as indicated by the highly shielded alpha-carbon (13)C NMR shifts (delta -6.1 and -7.4, respectively). In tetrahydrofuran only N-metalated mixed LiCH(2)CN dimers were observed for both Li-1 and Li-2 with the less shielded (13)C NMR shifts of delta -2.5 and -2.2 for the alpha-carbon of LiCH(2)CN of the complexes. PMID:15161308

Sott, Richard; Granander, Johan; Hilmersson, Göran

2004-06-01

238

Identifying the causes of contact dermatitis.  

PubMed

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

Jones, Ruth; Horn, Helen M

2014-06-01

239

Allergic contact dermatitis.  

PubMed

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

Becker, Detlef

2013-07-01

240

Contact problem for a transversely isotropic half-space with an unknown contact region  

NASA Astrophysics Data System (ADS)

A three-dimensional contact problem with an unknown contact region for a transversely isotropic half-space, when the isotropy planes are perpendicular to the half-space boundary, is investigated. The method described makes it possible to evaluate effectively the Brinell and Vickers hardness and the contact strength of materials, the near-surface properties of which can substantially depend on the direction (titanium, zinc, beryllium, cobalt, aluminum and zinc oxides, graphite, wood, temoral bone, sapphire, etc; five elastic constants). We use the fact that the kernel of the integral equation of a contact problem can be represented in a form free of quadratures. Such a form of the kernel, in view of the simplicity of its regularization in singular points, makes it possible to apply the method of nonlinear boundary integral equations developed by Galanov to solve the contact problem with an unknown contact region. To debug the computer program, an exact solution of the contact problem for a stamp shaped like an elliptic paraboloid is used. Calculations are made for various materials with the incorporation of the stamp shaped as a rectangular pyramid. The contact regions, pressures, and the values of the impressing force with the specified stamp immersion are determined.

Pozharskii, D. A.

2014-03-01

241

Lipophilic 1,1-bisphosphonates are potent squalene synthase inhibitors and orally active cholesterol lowering agents in vivo.  

PubMed

Squalene synthase catalyzes the reductive dimerization of two molecules of farnesyl diphosphate to form squalene at the final branchpoint of the cholesterol biosynthetic pathway. We report herein that isoprenyl 1,1-bisphosphonates and related analogs are potent inhibitors of rat microsomal squalene synthase (I50 = 0.7-32 nM). In addition, members of this family are potent inhibitors of cholesterol biosynthesis in rats on intravenous and oral dosing, as well as cholesterol lowering agents in rats and hamsters. Significant inhibition of cholesterol biosynthesis in rats by lovastatin occurs with a concomitant inhibition of dolichol and coenzyme-Q9 synthesis. In contrast, bisphosphonate 4 has no effect on dolichol and coenzyme-Q9 biosynthesis in rats under conditions where cholesterol biosynthesis is > 90% inhibited. PMID:8227045

Ciosek, C P; Magnin, D R; Harrity, T W; Logan, J V; Dickson, J K; Gordon, E M; Hamilton, K A; Jolibois, K G; Kunselman, L K; Lawrence, R M

1993-11-25

242

Low-contact-resistance graphene devices with nickel-etched-graphene contacts.  

PubMed

The performance of graphene-based transistors is often limited by the large electrical resistance across the metal-graphene contact. We report an approach to achieve ultralow resistance metal contacts to graphene transistors. Through a process of metal-catalyzed etching in hydrogen, multiple nanosized pits with zigzag edges are created in the graphene portions under source/drain metal contacts while the graphene channel remains intact. The porous graphene source/drain portions with pure zigzag-termination form strong chemical bonds with the deposited nickel metallization without the need for further annealing. This facile contact treatment prior to electrode metallization results in contact resistance as low as 100 ?·?m in single-layer graphene field-effect transistors, and 11 ?·?m in bilayer graphene transistors. Besides 96% reduction in contact resistance, the contact-treated graphene transistors exhibit 1.5-fold improvement in mobility. More importantly, the metal-catalyzed etching contact treatment is compatible with complementary metal-oxide-semiconductor (CMOS) fabrication processes, and holds great promise to meet the contact performance required for the integration of graphene in future integrated circuits. PMID:24328346

Leong, Wei Sun; Gong, Hao; Thong, John T L

2014-01-28

243

PROCEDURE CARDS EMERGENCY CONTACT INFORMATION  

E-print Network

/area off limits 3. Contact EHS or UD Public Safety for emergency assistance 4. If imminent danger exists and personal items while in shower · Contact UD Public Safety for emergency medical assistance or contact(s) open between finger and thumb · Contact UD Public Safety for emergency assistance CHEMICAL SPILL

Firestone, Jeremy

244

Occupational Contact Dermatitis  

PubMed Central

Occupational contact dermatitis accounts for 90% of all cases of work-related cutaneous disorders. It can be divided into irritant contact dermatitis, which occurs in 80% of cases, and allergic contact dermatitis. In most cases, both types will present as eczematous lesions on exposed parts of the body, notably the hands. Accurate diagnosis relies on meticulous history taking, thorough physical examination, careful reading of Material Safety Data Sheets to distinguish between irritants and allergens, and comprehensive patch testing to confirm or rule out allergic sensitization. This article reviews the pathogenesis and clinical manifestations of occupational contact dermatitis and provides diagnostic guidelines and a rational approach to management of these often frustrating cases. PMID:20525126

2008-01-01

245

Medicare: Helpful Contacts  

MedlinePLUS

... learn more about related websites Download Helpful Contacts Database You have the option of downloading the data ... data will be downloadable as zipped Microsoft Access databases. Health policy researchers and the media primarily use ...

246

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.

247

Contact alternatives to nickel.  

PubMed

Allergic contact dermatitis to nickel is a continued health concern internationally. Nickel has been found to be the most prevalent and relevant allergen in tested populations for the last 3 decades. Furthermore, recent data from the North American Contact Dermatitis Group demonstrate positive patch-test reactions to nickel at approximately 19.5% of their tested population and a significant increase in the positivity rates for the last decade (Dermatitis. 2013;24:10-21. J Am Acad Dermatol. 1998;38:911-918). Because of the rise in allergic contact dermatitis rates to nickel, the American Contact Dermatitis Society recognized nickel to be the 2008 Allergen of the Year (J Am Acad Dermatol. 2009;60:1067-1069; Dermatitis. 2008;19:3-8). This article recognizes the importance of nickel avoidance and highlights potential alternatives. PMID:24030370

Nijhawan, Rajiv I; Jacob, Sharon E

2013-01-01

248

Contacting My Donor Family  

MedlinePLUS

... Donor Family Newsroom Minorities Contacting My Donor Family Writing anything can be a challenge. Staring at a ... can take to get started. The process of writing your letter may take some time, but at ...

249

Admission Requirements Contact/ Information  

E-print Network

Integration, Teacher Professional Development, Literacy Education, Critical Literacy, Family LiteracyAdmission Requirements Contact/ Information Graduate Programs Dr. Emery Hyslop-Margison Department to the doctoral program · Two letters of recommendation Important information about applying to Graduate School

Fernandez, Eduardo

250

Admission Requirements Contact/ Information  

E-print Network

Integration, Teacher Professional Development, Literacy Education, Critical Literacy, Family LiteracyAdmission Requirements Contact/ Information Graduate Programs Dr. Emery Hyslop-Margison Department of recommendation · Statement of objectives Important information about applying to Graduate School: Transcripts

Fernandez, Eduardo

251

Admission Requirements Contact/ Information  

E-print Network

Integration, Teacher Professional Development, Literacy Education, Critical Literacy, Family LiteracyAdmission Requirements Contact/ Information Graduate Programs Dr. Barbara Ridener Department test score of 154 (verbal) and 144 (quantitative) Important information about applying to Graduate

Richman, Fred

252

Admission Requirements Contact/ Information  

E-print Network

Integration, Teacher Professional Development, Literacy Education, Critical Literacy, Family LiteracyAdmission Requirements Contact/ Information Graduate Programs Dr. Emery Hyslop-Margison Department certification or temporary certification · GRE Analytical Writing score of 3.5 Important information about

Richman, Fred

253

Contact thermal lithography  

E-print Network

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 ...

Schmidt, Aaron Jerome, 1979-

2004-01-01

254

Wetting and Contact Angle  

NSDL National Science Digital Library

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.

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

255

Buying Cosmetic Contact Lenses?  

MedlinePLUS

... information about the type of lenses, their manufacturer, power, base curve, and diameter. This article was previously available as Avoiding an Eyesore: What to Know Before You Buy Cosmetic Contacts.

256

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

257

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

258

Vaginal concentrations of lactic acid potently inactivate HIV  

PubMed Central

Objectives When Lactobacillus spp. dominate the vaginal microbiota of women of reproductive age they acidify the vagina to pH <4.0 by producing ?1% lactic acid in a nearly racemic mixture of d- and l-isomers. We determined the HIV virucidal activity of racemic lactic acid, and its d- and l-isomers, compared with acetic acid and acidity alone (by the addition of HCl). Methods HIV-1 and HIV-2 were transiently treated with acids in the absence or presence of human genital secretions at 37°C for different time intervals, then immediately neutralized and residual infectivity determined in the TZM-bl reporter cell line. Results l-lactic acid at 0.3% (w/w) was 17-fold more potent than d-lactic acid in inactivating HIVBa-L. Complete inactivation of different HIV-1 subtypes and HIV-2 was achieved with ?0.4% (w/w) l-lactic acid. At a typical vaginal pH of 3.8, l-lactic acid at 1% (w/w) more potently and rapidly inactivated HIVBa-L and HIV-1 transmitter/founder strains compared with 1% (w/w) acetic acid and with acidity alone, all adjusted to pH 3.8. A final concentration of 1% (w/w) l-lactic acid maximally inactivated HIVBa-L in the presence of cervicovaginal secretions and seminal plasma. The anti-HIV activity of l-lactic acid was pH dependent, being abrogated at neutral pH, indicating that its virucidal activity is mediated by protonated lactic acid and not the lactate anion. Conclusions l-lactic acid at physiological concentrations demonstrates potent HIV virucidal activity distinct from acidity alone and greater than acetic acid, suggesting a protective role in the sexual transmission of HIV. PMID:23657804

Aldunate, Muriel; Tyssen, David; Johnson, Adam; Zakir, Tasnim; Sonza, Secondo; Moench, Thomas; Cone, Richard; Tachedjian, Gilda

2013-01-01

259

Allergic contact dermatitis: cosmetics  

Microsoft Academic Search

\\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

Anton C. de Groot; Carolus-Liduina Ziekenhuis

260

Contact Allergy in Children  

Microsoft Academic Search

\\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

Marie-Anne Morren; An Goossens

261

Synthesis of Novel Compounds as New Potent Tyrosinase Inhibitors  

PubMed Central

In the present paper, we report the synthesis and pharmacological evaluation of a new series of azo compounds with different groups (1-naphthol, 2-naphthol, and N,N-dimethylaniline) and trifluoromethoxy and fluoro substituents in the scaffold. All synthesized compounds (5a–5f) showed the most potent mushroom tyrosinase inhibition (IC50 values in the range of 4.39 ± 0.76–1.71 ± 0.49?µM), comparable to the kojic acid, as reference standard inhibitor. All the novel compounds were characterized by FT-IR, 1H NMR, 13C NMR, and elemental analysis. PMID:24260737

Hamidian, Hooshang

2013-01-01

262

Pyrazolopyridines as potent PDE4B inhibitors: 5-Heterocycle SAR  

SciTech Connect

Following the discovery of 4-(substituted amino)-1-alkyl-pyrazolo[3,4-b]pyridine-5-carboxamides as potent and selective phosphodiesterase 4B inhibitors, [Hamblin, J. N.; Angell, T.; Ballentine, S., et al. Bioorg. Med. Chem. Lett.2008, 18, 4237] the SAR of the 5-position was investigated further. A range of substituted heterocycles showed good potencies against PDE4. Optimisation using X-ray crystallography and computational modelling led to the discovery of 16, with sub-nM inhibition of LPS-induced TNF-{alpha} production from isolated human peripheral blood mononuclear cells.

Mitchell, Charlotte J.; Ballantine, Stuart P.; Coe, Diane M.; Cook, Caroline M.; Delves, Christopher J.; Dowle, Mike D.; Edlin, Chris D.; Hamblin, J. Nicole; Holman, Stuart; Johnson, Martin R.; Jones, Paul S.; Keeling, Sue E.; Kranz, Michael; Lindvall, Mika; Lucas, Fiona S.; Neu, Margarete; Solanke, Yemisi E.; Somers, Don O.; Trivedi, Naimisha A.; Wiseman, Joanne O. (GSK)

2012-05-03

263

Discovery of Potent Dual PPAR? Agonists/CB1 Ligands  

PubMed Central

This letter describes the synthesis and in vitro and in vivo evaluation of dual ligands targeting the cannabinoid and peroxisome proliferator-activated receptors (PPAR). These compounds were obtained from fusing the pharmacophores of fibrates and the diarylpyrazole rimonabant, a cannabinoid receptor antagonist. They are the first examples of dual compounds with nanomolar affinity for both PPAR? and cannabinoid receptors. Besides, lead compound 2 proved to be CB1 selective. Unexpectedly, the phenol intermediates tested were equipotent (compound 1 as compared to 2) or even more potent (compound 3 as compared with 4). This discovery opens the way to design new dual ligands. PMID:24936232

2011-01-01

264

Discovery of potent, selective sulfonylfuran urea endothelial lipase inhibitors.  

PubMed

Endothelial lipase (EL) activity has been implicated in HDL catabolism, vascular inflammation, and atherogenesis, and inhibitors are therefore expected to be useful for the treatment of cardiovascular disease. Sulfonylfuran urea 1 was identified in a high-throughput screening campaign as a potent and non-selective EL inhibitor. A lead optimization effort was undertaken to improve potency and selectivity, and modifications leading to improved LPL selectivity were identified. Radiolabeling studies were undertaken to establish the mechanism of action for these inhibitors, which were ultimately demonstrated to be irreversible inhibitors. PMID:19058966

Goodman, Krista B; Bury, Michael J; Cheung, Mui; Cichy-Knight, Maria A; Dowdell, Sarah E; Dunn, Allison K; Lee, Dennis; Lieby, Jeffrey A; Moore, Michael L; Scherzer, Daryl A; Sha, Deyou; Suarez, Dominic P; Murphy, Dennis J; Harpel, Mark R; Manas, Eric S; McNulty, Dean E; Annan, Roland S; Matico, Rosalie E; Schwartz, Benjamin K; Trill, John J; Sweitzer, Thomas D; Wang, Da-Yuan; Keller, Paul M; Krawiec, John A; Jaye, Michael C

2009-01-01

265

Novel racemic tetrahydrocurcuminoid dihydropyrimidinone analogues as potent acetylcholinesterase inhibitors.  

PubMed

The synthesis of racemic tetrahydrocurcumin- (THC-), tetrahydrodemethoxycurcumin- (THDC-) and tetrahydrobisdemethoxycurcumin- (THBDC-) dihydropyrimidinone (DHPM) analogues was achieved by utilizing the multi-component Biginelli reaction in the presence of copper sulphate as a catalyst. The evaluation of acetylcholinesterase inhibitors for Alzheimer's disease of these compounds showed that they exhibited higher inhibitory activity than their parent analogues. THBDC-DHPM demonstrated the most potent inhibitory activity with an IC50 value of 1.34±0.03?M which was more active than the approved drug galanthamine (IC50=1.45±0.04?M). PMID:23583510

Arunkhamkaew, Sarawalee; Athipornchai, Anan; Apiratikul, Nuttapon; Suksamrarn, Apichart; Ajavakom, Vachiraporn

2013-05-15

266

Aurones: A Promising Heterocyclic Scaffold for the Development of Potent Antileishmanial Agents  

PubMed Central

A series of (Z)-2-benzylidenebenzofuran-3-(2H)-ones (aurones) bearing a variety of substituents on rings A and B were synthesized and evaluated for their antiparasitic activity against the intracellular amastigote form of Leishmania infantum and their cytotoxicity against human THP1-differentiated macrophages. In general, aurones bearing no substituents on ring A (compounds 4a–4f) exhibit higher toxicity than aurones with 4,6-dimethoxy substitution (compounds 4g–4l). Among the latter, two aurones possessing a 2?-methoxy or a 2?-methyl group (compounds 4i and 4j) exhibit potent antileishmanial activity (IC50 = 1.3 ± 0.1??M and IC50 = 1.6 ± 0.2??M, resp.), comparable to the activity of the reference drug Amphotericin B, whereas they present significantly lower cytotoxicity than Amphotericin B as deduced by the higher selectivity index. PMID:25374683

Roussaki, Marina; Costa Lima, Sofia; Kypreou, Anna-Maria; Kefalas, Panagiotis; Cordeiro da Silva, Anabela; Detsi, Anastasia

2012-01-01

267

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

PubMed Central

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

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

2013-01-01

268

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

PubMed

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

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

269

2-(Hetero(aryl)methylene)hydrazine-1-carbothioamides as Potent Urease Inhibitors.  

PubMed

A small series of 2-(hetero(aryl)methylene) hydrazine-1-carbothioamides including two aryl derivatives was synthesized and tested for their inhibitory activity against urease. Compound (E)-2-(Furan-2-ylmethylene) hydrazine-1-carbothioamide (3f), having a furan ring, was the most potent inhibitor of urease with an IC50 value of 0.58 ?m. Molecular modeling was carried out through docking the designed compounds into the urease binding site to predict whether these derivatives have analogous binding mode to the urease inhibitors. The study revealed that all of the tested compounds bind with both metal atoms at the active site of the enzyme. The aromatic ring of the compounds forms ionic interactions with the residues, Ala(440), Asp(494), Ala(636), and Met(637). PMID:24938644

Saeed, Aamer; Imran, Aqeel; Channar, Pervaiz A; Shahid, Mohammad; Mahmood, Wajahat; Iqbal, Jamshed

2015-02-01

270

Contact mechanics - Computational techniques; Proceedings of the 1st International Conference on Contact Mechanics, Southampton, United Kingdom, July 1993  

NASA Astrophysics Data System (ADS)

The papers presented in this volume focus on mechanical models, such as rolling, impact and shock, and unilateral contact; numerical models, such as finite element method, boundary element method, and mathematical programming; engineering applications, including fracture mechanics, composite materials, and forming processes; and mathematical models, such as variational inequalities and the Lagrangian multiplier. Specific topics discussed include neural networks for computing contact problems; multigrid method applied to mixed formulation for frictional contact problems; a competitive game formulation for large scale frictional contact problems; and numerical modeling of contact for low velocity impact damage in composite laminates.

Aliabadi, M. H.; Brebbia, C. A.

271

Contact Lenses for Vision Correction  

MedlinePLUS

... Eye Health News Consumer Alerts Contact Lenses for Vision Correction Tweet What are contacts? Contact lenses are ... on the surface of the eye. They correct vision like eyeglasses do and are safe when used ...

272

Potent hypoglycemic effect of Nigerian anti-diabetic medicinal plants.  

PubMed

The objective of this paper was to investigate the phytochemistry and hypoglycemic activities of aqueous extracts of Anisopus mannii, Daniella olivieri, Detarium macrocarpum, Leptedenia hastate and Mimosa invisa, traditionally prescribed for diabetes mellitus. The aqueous extracts were tested for phytochemicals and free radical scavenging activity by the DPPH assay. The antidiabetic tests were performed in normoglycemic and alloxan induced diabetic mice. High intensity of saponins, xanthones, tannins and glycosides were detected in A. mannii, D. macrocarpum and M. invisa, respectively. For the free radical scavenging activity, D. macrocarpum showed the highest activity with an IC50 of 0.027 mg/ml which was 2.1 folds of ascorbic acid. All extracts showed potent hypoglycemic effects in alloxan induced diabetic mice with the highest fasting blood glucose reduction of 70.39 percent in A. mannii which was 1.54 and 0.98 fold of glibenclamide and human insulin, respectively. A. mannii showed the potent hypoglycemic activity which was 1.54 and 0.98 fold of glibenclamide and insulin, respectively. This study confirmed the traditional use of these Nigerian medicinal plants in diabetes treatment. These plants showed high potential for further investigation to novel anti-diabetic drugs. PMID:22754948

Manosroi, Jiradej; Zaruwa, Moses Z; Manosroi, Aranya

2011-01-01

273

Celecoxib: a potent cyclooxygenase-2 inhibitor in cancer prevention.  

PubMed

Non-steroidal anti-inflammatory drugs (NSAIDs) are the most widely used therapeutic agents in the treatment of pain, inflammation and fever. They may also have a role in the management of cancer prevention, Alzheimer's disease and prophylaxis against cardiovascular disease. These drugs act primarily by inhibiting cyclooxygenase enzyme, which has two isoforms, cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). Selective COX-2 inhibitors provide potent anti-inflammatory and analgesic effects without the side effects of gastric and renal toxicity and inhibition of platelet function. Celecoxib is a potent COX-2 inhibitor being developed for the treatment of rheumatoid arthritis and osteoarthritis. Chemoprevention is the use of pharmacological or natural agents to prevent, suppress, interrupt or reverse the process of carcinogenesis. For this purpose, celecoxib is being used for different cancer types. The effects of NSAIDs on tumor growth remain unclear, but are most likely to be multifocal. In this article, we reviewed COX-2 selectivity, the pharmacological properties of celecoxib, the use of celecoxib for cancer prevention and the mechanisms of chemoprevention. PMID:15068837

Kismet, Kemal; Akay, M Turan; Abbasoglu, Osman; Ercan, Aygün

2004-01-01

274

Potent inhibitors of LXXLL-based protein-protein interactions.  

PubMed

Protein-protein interactions between estrogen receptors, ERalpha and ERbeta, and their coactivators (CoAs) are an attractive target for drug intervention. This interaction is mediated by a small pentapeptide motif (LXXLL), termed the NR box. Based on this motif, a variety of cyclic and linear peptides were synthesized in order to gain a better understanding of the association of CoA proteins with the ER isoforms. Utilizing a time-resolved florescence-based coactivator interaction assay, we determined the abilities of these peptides to inhibit this interaction. Using molecular modeling and CD spectroscopy, we have examined the structural basis of their bioactivities with both hormone receptor isoforms. Either homocysteine or penicillamine was utilized as a substitute for cysteine in the disulfide-bridged peptides, while tertiary leucine and neopentyl glycine were used as the surrogates for the NR box leucines. The most potent disufide-bridged peptide (K(i)= 70 pM, with ERalpha) incorporates neopentyl glycine in the NR box, while the most active peptide in this series with ERbeta (K(i)=350 pM) incorporates tertiary leucine. Surprisingly, several linear peptides containing a single cysteine residue showed activities with low nanomolar K(i) values. Collectively, our results suggest a synthetic approach for designing potent and selective peptidomimetics for ERalpha and ERbeta interactions with CoA proteins effecting estrogen action. PMID:16222726

Galande, Amit K; Bramlett, Kelli S; Trent, John O; Burris, Thomas P; Wittliff, James L; Spatola, Arno F

2005-11-01

275

Potent Reversible Inhibition of Myeloperoxidase by Aromatic Hydroxamates*  

PubMed Central

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

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

276

Contact induced deformation of enamel  

NASA Astrophysics Data System (ADS)

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.

He, Li Hong; Swain, Michael V.

2007-04-01

277

LEAD FREE SOLDERING ON CONTACT PADS  

Microsoft Academic Search

In this article are presented results from the investigations of some peculiarities in the process of soldering on small topological forms in PCBs. The investigation is dedicated to the surface mount technology and deals with lead contained and lead free solder alloy pastes. Attention is paid on the implementation of contact pads with lead free surface finish. For this purpose

Valentin Hristov Videkov; Svetozar Krastev Andreev; Nikola Stefanov

278

Bisbenzimidazole derivatives as potent inhibitors of the trypsin-like sites of the immunoproteasome core particle.  

PubMed

In this study, a monomeric (MB) and a dimeric (DB) bisbenzimidazoles were identified as novel proteasome inhibitors of the trypsin-like activity located on ?2c sites of the constitutive 20S proteasome (IC50 values at 2-4 ?M range). Remarkably, they were further shown to be 100- and 200-fold more potent inhibitors of the immunoproteasome trypsin-like activity (?2i sites, IC50 = 24 nM) than of the homologous constitutive activity. Molecular models of inhibitor/enzyme complexes in the two types of trypsin-like sites and corresponding computed binding energy values corroborated kinetic data. Different binding modes were suggested for MB and DB to the ?2c and ?2i trypsic sites. Each pointed to better contacts of the ligand inside the ?2i active site than for ?2c site. MB and DB represent the first selective inhibitors of the immunoproteasome trypsin-like activity described to date and can be considered as prototypes for inhibiting this activity. PMID:25446655

Koroleva, Olga N; Pham, The Hien; Bouvier, Dominique; Dufau, Laure; Qin, Lixian; Reboud-Ravaux, Michèle; Ivanov, Alexander A; Zhuze, Alexei L; Gromova, Elizaveta S; Bouvier-Durand, Michelle

2015-01-01

279

Oral mucosal progenitor cells are potently immunosuppressive in a dose-independent manner.  

PubMed

Oral mucosal lamina propria progenitor cells (OMLP-PCs) are a novel, clonally derived PC population of neural crest origin with the potential to differentiate down both mesenchymal and neuronal cell lineages. In this study we aimed to determine the immunological properties of OMLP-PCs and to establish whether they would be suitable candidates for allogeneic tissue engineering and in the treatment of immune-related diseases. OMLP-PCs demonstrated no inherent immunogenicity with insignificant expression of costimulatory molecules (CD40, CD80, CD86, CD154, and CD178) or human leukocyte antigen (HLA) class II. OMLP-PCs required 7 days of stimulation with interferon-? (IFN-?) to induce cell surface expression of HLA II. Mixed lymphocyte cultures and mitogen stimulation demonstrated the potent immunosuppressive capability of OMLP-PCs in a contact-independent manner. Complete inhibition of lymphocyte proliferation was seen at doses as low as 0.001% OMLP-PCs to responder lymphocytes, while annexin V staining confirmed that this immunosuppressive effect was not due to the induction of lymphocyte apoptosis. These data demonstrate, for the first time, that OMLP-PC immunomodulation, unlike that for mesenchymal stem cells, occurs via a dose- and HLA II-independent mechanism by the release of immunosuppressive soluble factors and suggests these cells may have wide ranging potential in future immune-related therapies. PMID:21988324

Davies, Lindsay C; Lönnies, Helena; Locke, Matthew; Sundberg, Berit; Rosendahl, Kerstin; Götherström, Cecilia; Le Blanc, Katarina; Stephens, Phil

2012-06-10

280

Intergroup contact theory.  

PubMed

Allport specified four conditions for optimal intergroup contact: equal group status within the situation, common goals, intergroup cooperation and authority support. Varied research supports the hypothesis, but four problems remain. 1. A selection bias limits cross-sectional studies, since prejudiced people avoid intergroup contact. Yet research finds that the positive effects of cross-group friendship are larger than those of the bias. 2. Writers overburden the hypothesis with facilitating, but not essential, conditions. 3. The hypothesis fails to address process. The chapter proposes four processes: learning about the outgroup, changed behavior, affective ties, and ingroup reappraisal. 4. The hypothesis does not specify how the effects generalize to other situations, the outgroup or uninvolved outgroups. Acting sequentially, three strategies enhance generalization-decategorization, salient categorization, and recategorization. Finally, both individual differences and societal norms shape intergroup contact effects. The chapter outlines a longitudinal intergroup contact theory. It distinguishes between essential and facilitating factors, and emphasizes different outcomes for different stages of contact. PMID:15012467

Pettigrew, T F

1998-01-01

281

Electrical contacts for a thin-film semiconductor device  

DOEpatents

A method of fabricating spaced-apart back contacts on a thin film of semiconductor material by forming strips of buffer material on top of the semiconductor material in locations corresponding to the desired dividing lines between back contacts, forming a film of metal substantially covering the semiconductor material and buffer strips, and scribing portions of the metal film overlying the buffer strips with a laser without contacting the underlying semiconductor material to separate the metal layer into a plurality of back contacts. The buffer material serves to protect the underlying semiconductor material from being damaged during the laser scribing. Back contacts and multi-cell photovoltaic modules incorporating such back contacts also are disclosed.

Carlson, David E. (Yardley, PA); Dickson, Charles R. (Pennington, NJ); D'Aiello, Robert V. (East Brunswick, NJ)

1989-08-08

282

Shoe allergic contact dermatitis.  

PubMed

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

Matthys, Erin; Zahir, Amir; Ehrlich, Alison

2014-01-01

283

Method for forming materials  

DOEpatents

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.

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

284

Design and fabrication stable LNF contact for future IC application  

NASA Astrophysics Data System (ADS)

Enable the design of a small contact spring for applications requiring high density, high speed and high durability. A low normal force (LNF) contact spring with high performance is fabricated using a unique combined MEMS photo resist lithography and electro fine forming (EFF) technology. Reducing a total contact material cost of a connector, a high-Hertz stress with LNF contact will be a key technology in the future. Only radius R 5?m tip with 0.1N force contact provides an excellent electrical performance which is much sharper than conventional contact. 0.30million cycle's durability test was passed at 300?m displacement and the contact resistance was <=50m?.

Bhuiyan, M. M. I.; Rashid, M. M.; Ahmed, Sayem; Bhuiyan, M.; Kajihara, M.

2013-12-01

285

[Contact dermatitis: an approach used by a medical officer].  

PubMed

The article deals with contact dermatitis issues, that are of interest not only for dermatologists and specialists in professional pathology, but as well as for general practitioners. Issues of contact dermatitis classification, pathogenic peculiarities of the disease main forms and their basic causes are discussed. Clinical manifestations of irritative and allergic contact dermatitis are described in detail, aspects of differential diagnostics analysed. A detailed consideration is given to allergic diagnostics of contact dermatitis using application test-systems with the most common contact allergens. Main principles of contact dermatitis treatment are outlined in the article. The necessity of a complex approach to this disease therapy that requires not only external therapy, but the compliance with an appropriate treatment regimen, diet as well as application of a particular system therapy is shown. Recommendations for contact dermatitis prophylaxis are given. PMID:22545447

Vologzhanin, D A; Bozhchenko, A A; Bala, A M

2012-01-01

286

Hidden contacts with penicillin*  

PubMed Central

There is much evidence to indicate that the most common cause of drug allergy in recent years has been penicillin, and sensitive patients are warned to avoid treatment with this antibiotic. There are, however, a number of less obvious ways in which the penicillin-sensitive person may be exposed to the risk of contact with this drug, even minute amounts of which have been shown to cause allergic reactions. Four of the main hidden sources of such contact are discussed in detail in this paper. PMID:14446462

Siegel, Bernard B.

1959-01-01

287

Friction, wear and electrical contact resistance of precious metal alloys  

NASA Astrophysics Data System (ADS)

The preferred selection of precious metal electrical contact materials depends on the contact geometry, contact stress, test ambient values of electrical contact resistance and whether friction and/or wear must be controlled. Wiper-type contact couples that operate in dry hydrocarbon-free atmospheres, particularly if low and steady friction coefficients and minimal wear are required, are typically that of a palladium alloy pin (ASTM B540) sliding on a gold alloy plate (ASTM B541). These materials have a contact resistance of approximately ten milliohms and a friction coefficient less than 0.5 for the most common operational environments. Segregation of sulfur up to a few atomic percent to wear tracks formed on the gold alloy is not detrimental. The accumulation of larger concentrations of sulfur can form surface films of cuprous sulfide which increases the contact resistance to a few tens of milliohms. Large electrical contact resistances (greater than one ohm) are measured only when rider wear becomes dominant and ridges of Pd-containing material are formed in wear tracks. Ion implantation of carbon into the Au alloy decreases the friction coefficient without increasing the electrical contact resistance.

Pope, L. E.; Peebles, D. E.; Barton, B. M.

288

Cystobactamids: myxobacterial topoisomerase inhibitors exhibiting potent antibacterial activity.  

PubMed

The development of new antibiotics faces a severe crisis inter?alia owing to a lack of innovative chemical scaffolds with activities against Gram-negative and multiresistant pathogens. Herein, we report highly potent novel antibacterial compounds, the myxobacteria-derived cystobactamids 1-3, which were isolated from Cystobacter sp. and show minimum inhibitory concentrations in the low ?g?mL(-1) range. We describe the isolation and structure elucidation of three congeners as well as the identification and annotation of their biosynthetic gene cluster. By studying the self-resistance mechanism in the natural producer organism, the molecular targets were identified as bacterial type?IIa topoisomerases. As quinolones are largely exhausted as a template for new type II topoisomerase inhibitors, the cystobactamids offer exciting alternatives to generate novel antibiotics using medicinal chemistry and biosynthetic engineering. PMID:25510965

Baumann, Sascha; Herrmann, Jennifer; Raju, Ritesh; Steinmetz, Heinrich; Mohr, Kathrin I; Hüttel, Stephan; Harmrolfs, Kirsten; Stadler, Marc; Müller, Rolf

2014-12-22

289

The Potent Oxidant Anticancer Activity of Organoiridium Catalysts**  

PubMed Central

Platinum complexes are the most widely used anticancer drugs; however, new generations of agents are needed. The organoiridium(III) complex [(?5-Cpxbiph)Ir(phpy)(Cl)] (1-Cl), which contains ?-bonded biphenyltetramethylcyclopentadienyl (Cpxbiph) and C?N-chelated phenylpyridine (phpy) ligands, undergoes rapid hydrolysis of the chlorido ligand. In contrast, the pyridine complex [(?5-Cpxbiph)Ir(phpy)(py)]+ (1-py) aquates slowly, and is more potent (in nanomolar amounts) than both 1-Cl and cisplatin towards a wide range of cancer cells. The pyridine ligand protects 1-py from rapid reaction with intracellular glutathione. The high potency of 1-py correlates with its ability to increase substantially the level of reactive oxygen species (ROS) in cancer cells. The unprecedented ability of these iridium complexes to generate H2O2 by catalytic hydride transfer from the coenzyme NADH to oxygen is demonstrated. Such organoiridium complexes are promising as a new generation of anticancer drugs for effective oxidant therapy. PMID:24616129

Liu, Zhe; Romero-Canelón, Isolda; Qamar, Bushra; Hearn, Jessica M; Habtemariam, Abraha; Barry, Nicolas P E; Pizarro, Ana M; Clarkson, Guy J; Sadler, Peter J

2014-01-01

290

DXR inhibition by potent mono- and disubstituted fosmidomycin analogues.  

PubMed

The antimalarial compound fosmidomycin targets DXR, the enzyme that catalyzes the first committed step in the MEP pathway, producing the essential isoprenoid precursors, isopentenyl diphosphate and dimethylallyl diphosphate. The MEP pathway is used by a number of pathogens, including Mycobacterium tuberculosis and apicomplexan parasites, and differs from the classical mevalonate pathway that is essential in humans. Using a structure-based approach, we designed a number of analogues of fosmidomycin, including a series that are substituted in both the C? and the hydroxamate positions. The latter proved to be a stable framework for the design of inhibitors that extend from the polar and cramped (and so not easily druggable) substrate-binding site and can, for the first time, bridge the substrate and cofactor binding sites. A number of these compounds are more potent than fosmidomycin in terms of killing Plasmodium falciparum in an in vitro assay; the best has an IC50 of 40 nM. PMID:23819803

Jansson, Anna M; Wi?ckowska, Anna; Björkelid, Christofer; Yahiaoui, Samir; Sooriyaarachchi, Sanjeewani; Lindh, Martin; Bergfors, Terese; Dharavath, Shyamraj; Desroses, Matthieu; Suresh, Surisetti; Andaloussi, Mounir; Nikhil, Rautela; Sreevalli, Sharma; Srinivasa, Bachally R; Larhed, Mats; Jones, T Alwyn; Karlén, Anders; Mowbray, Sherry L

2013-08-01

291

Biosynthesis of the Potent Antimalarial Compound FR900098  

PubMed Central

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

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

2008-01-01

292

Genomic discovery of potent chromatin insulators for human gene therapy.  

PubMed

Insertional mutagenesis and genotoxicity, which usually manifest as hematopoietic malignancy, represent major barriers to realizing the promise of gene therapy. Although insulator sequences that block transcriptional enhancers could mitigate or eliminate these risks, so far no human insulators with high functional potency have been identified. Here we describe a genomic approach for the identification of compact sequence elements that function as insulators. These elements are highly occupied by the insulator protein CTCF, are DNase I hypersensitive and represent only a small minority of the CTCF recognition sequences in the human genome. We show that the elements identified acted as potent enhancer blockers and substantially decreased the risk of tumor formation in a cancer-prone animal model. The elements are small, can be efficiently accommodated by viral vectors and have no detrimental effects on viral titers. The insulators we describe here are expected to increase the safety of gene therapy for genetic diseases. PMID:25580597

Liu, Mingdong; Maurano, Matthew T; Wang, Hao; Qi, Heyuan; Song, Chao-Zhong; Navas, Patrick A; Emery, David W; Stamatoyannopoulos, John A; Stamatoyannopoulos, George

2015-02-01

293

Development of potent inhibitors of the coxsackievirus 3C protease  

SciTech Connect

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.

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

294

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

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

295

Are genotoxic carcinogens more potent than nongenotoxic carcinogens?  

PubMed Central

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

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

1991-01-01

296

Polyoxometalates-Potent and selective ecto-nucleotidase inhibitors.  

PubMed

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: 3.88nM). Other investigated POMs selectively inhibited human NPP1, [TiW11CoO40](8-) (4, PSB-POM141, Ki: 1.46nM) and [NaSb9W21O86](18-) (6, PSB-POM143, Ki: 4.98nM) 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

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

2014-11-13

297

Allergic contact dermatitis in children.  

PubMed

Allergic contact dermatitis is an inflammatory skin disease (delayed type hypersensitivity reaction) that accounts for up to 20% of all childhood dermatitis. Allergic contact dermatitis represents a clinical manifestation of contact sensitization and usually occurs at skin sites that have come into contact with the allergen. The clinical features of allergic contact dermatitis are itchy eczematous lesions. Prevalence of contact sensitization varies between 27% and 96% of children with suspected contact dermatitis. The relationship between contact sensitization and atopic dermatitis has been widely discussed but only conflicting data have been reported. Epicutaneous patch testing is the gold standard for the diagnosis of allergic contact dermatitis. The most common allergens detected in children are: metals, topical medicaments, fragrances, and preservatives. The first line management of allergic contact dermatitis in children is to avoid the offending allergens identified with the patch test and a topical corticosteroid therapy. PMID:25315290

Fontana, E; Belloni Fortina, A

2014-12-01

298

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:

299

Does Contact Area Matter?  

NSDL National Science Digital Library

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.

2014-09-18

300

Program Contact Anthropology 62210  

E-print Network

62500 Classics (Ancient Greek & Roman Studies) 62180 Comparative Humanities 63045 Computational Studio Art 62655 Teaching Hebrew 62950 Teaching Chinese as a Foreign Language 62961 Theater Arts: Acting 63356 Women's & Gender Studies 63045 Departmental Contact List Graduate School of Arts and Sciences

Fraden, Seth

301

Have Confidence in Contact  

ERIC Educational Resources Information Center

In an article in the May-June 2009 "American Psychologist," we discussed a new approach to reducing prejudice and encouraging more positive intergroup relations (Crisp & Turner, 2009). We named the approach imagined intergroup contact and defined it as "the mental simulation of a social interaction with a member or members of an outgroup category"…

Crisp, Richard J.; Turner, Rhiannon N.

2010-01-01

302

Technology Advertising Contact Information  

E-print Network

space travel, nano-technology, medical breakthroughs and more! News Breaking technology news, fromOverview #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

Peters, Richard

303

[Contact allergies in musicians].  

PubMed

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

Gasenzer, E R; Neugebauer, E A M

2012-12-01

304

Multilingual Contacts in Brussels.  

ERIC Educational Resources Information Center

This article attempts to present an exhaustive, fully-documented discussion of recent and current work around the world on questions related to French/Dutch multilingual contact in Brussels. An attempt has been made to go beyond mere bibliographical listing to an evaluation of everything of importance written around this topic, primarily in the…

Universite Libre de Bruxelles (Belgium). Institut de Phonetique.

305

Contact: Releasing the news  

NASA Astrophysics Data System (ADS)

The problem of mass behavior after man's future contacts with other intelligences in the universe is not only a challenge for social scientists and political leaders all over the world, but also a cultural time bomb as well. In fact, since the impact of CETI (Contact with Extraterrestrial Intelligence) on human civilization, with its different cultures, might cause a serious socio-anthropological shock, a common and predetermined worldwide strategy is necessary in releasing the news after the contact, in order to keep possible manifestations of fear, panic and hysteria under control. An analysis of past studies in this field and of parallel historical situations as analogs suggests a definite "authority crisis" in the public as a direct consequence of an unexpected release of the news, involving a devastating "chain reaction" process (from both the psychological and sociological viewpoints) of anomie and maybe the collapse of today's society. The only way to prevent all this is to prepare the world's public opinion concerning contact before releasing the news, and to develop a long-term strategy through the combined efforts of scientists, political leaders, intelligence agencies and the mass media, in order to create the cultural conditions in which a confrontation with ETI won't affect mankind in a traumatic way. Definite roles and tasks in this multi-level model are suggested.

Pinotti, Roberto

306

Plasticity in fretting contact  

Microsoft Academic Search

The fretting problem of a cyclically loaded cylinder on a flat elastic–plastic surface is analyzed under the assumption of plane strain. Severe fretting conditions are modeled by applying a constant normal load and a cyclic tangential load to the cylinder and describing the contact behavior using a Coulomb friction law. Detailed numerical results are presented for the evolution of plastic

J. M. Ambrico; M. R. Begley

2000-01-01

307

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.

308

Thermal Contact Conductance  

NASA Technical Reports Server (NTRS)

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.

Salerno, Louis J.; Kittel, Peter

1997-01-01

309

Non-hinge-binding pyrazolo[1,5-a]pyrimidines as potent B-Raf kinase inhibitors  

SciTech Connect

As part of our research effort to discover B-Raf kinase inhibitors, we prepared a series of C-3 substituted N-(3-(pyrazolo[1,5-a]pyrimidin-7-yl)phenyl)-3-(trifluoromethyl)benzamides. X-ray crystallography studies revealed that one of the more potent inhibitors (10n) bound to B-Raf kinase without forming a hinge-binding hydrogen bond. With basic amine residues appended to C-3 aryl residues, cellular activity and solubility were enhanced over previously described compounds of this class.

Berger, Dan M.; Torres, Nancy; Dutia, Minu; Powell, Dennis; Ciszewski, Greg; Gopalsamy, Ariamala; Levin, Jeremy I.; Kim, Kyung-Hee; Xu, Weixin; Wilhelm, James; Hu, YongBo; Collins, Karen; Feldberg, Larry; Kim, Steven; Frommer, Eileen; Wojciechowicz, Donald; Mallon, Robert; (Wyeth)

2010-11-19

310

Chemokine CXCL1 dimer is a potent agonist for the CXCR2 receptor.  

PubMed

The CXCL1/CXCR2 axis plays a crucial role in recruiting neutrophils in response to microbial infection and tissue injury, and dysfunction in this process has been implicated in various inflammatory diseases. Chemokines exist as monomers and dimers, and compelling evidence now exists that both forms regulate in vivo function. Therefore, knowledge of the receptor activities of both CXCL1 monomer and dimer is essential to describe the molecular mechanisms by which they orchestrate neutrophil function. The monomer-dimer equilibrium constant (~20 ?m) and the CXCR2 binding constant (1 nm) indicate that WT CXCL1 is active as a monomer. To characterize dimer activity, we generated a trapped dimer by introducing a disulfide across the dimer interface. This disulfide-linked CXCL1 dimer binds CXCR2 with nanomolar affinity and shows potent agonist activity in various cellular assays. We also compared the receptor binding mechanism of this dimer with that of a CXCL1 monomer, generated by deleting the C-terminal residues that stabilize the dimer interface. We observe that the binding interactions of the dimer and monomer to the CXCR2 N-terminal domain, which plays an important role in determining affinity and activity, are essentially conserved. The potent activity of the CXCL1 dimer is novel: dimers of the CC chemokines CCL2 and CCL4 are inactive, and the dimer of the CXC chemokine CXCL8 (which is closely related to CXCL1) is marginally active for CXCR1 but shows variable activity for CXCR2. We conclude that large differences in dimer activity among different chemokine-receptor pairs have evolved for fine-tuned leukocyte function. PMID:23479735

Ravindran, Aishwarya; Sawant, Kirti V; Sarmiento, Jose; Navarro, Javier; Rajarathnam, Krishna

2013-04-26

311

Systemic contact dermatitis to foods: nickel, BOP, and more.  

PubMed

Systemic contact dermatitis (SCD), a cutaneous reaction that is a direct manifestation of systemic exposure to a known allergen in a sensitized individual, has been increasingly recognized as a cause of persistent cutaneous contact dermatitis that is refractory to conventional therapies. While SCD in response to drugs has been described well in the literature, SCD to allergens in common foodstuffs is a less well-articulated phenomenon. Several foods that are universally consumed throughout the world contain potent allergens including nickel, balsam of Peru, trace metals, urushiol, and sesquiterpene lactones as well as a host of others that may cause a distinctive clinical picture. In this review article, the authors review the typical presentation and prevalence of SCD to foods, pathophysiology, the most common offensive ingestible food allergens, several appropriate diets, and effectiveness of dietary avoidance for situations in which SCD is suspected. PMID:25149165

Fabbro, Stephanie K; Zirwas, Matthew J

2014-10-01

312

Contact dermatitis from a presumed allergy to paraphenylenediamine.  

PubMed

Paraphenylenediamine (PPD) is a potent skin allergen found in permanent hair dye and temporary henna tattoo ink. Several cases of adverse skin reactions to PPD have been reported in the literature. Here we present a case involving a patient who acquired a temporary tattoo while vacationing in Mexico and subsequently developed contact dermatitis at the tattoo site. He provided a history of permanent hair dye use in the past with associated cutaneous reaction. Temporary tattoos have become increasingly popular with travelers and as a result so have reports of associated allergic contact dermatitis. Of concern is cross-reaction of PPD to related compounds, severe reactions in younger populations and sequelae including increased sensitization, permanent scarring, and persistent postinflammatory hyperpigmentation. PMID:19958436

Hansen, Daniel; Voutsalath, Melissa

2009-12-01

313

Seal for fluid forming tools  

DOEpatents

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.

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

2012-03-20

314

STABILITY OF FINITE ELEMENT MIXED INTERPOLATIONS FOR CONTACT PROBLEMS  

E-print Network

contact between bodies are, for example, analysed in mechanical designs of seals, in soil-structure interactions, in the analyses of bridges, in metal forming simulations, and in automobile crash and crush

Brezzi, Franco

315

76 FR 29243 - Agency Forms Undergoing Paperwork Reduction Act Review  

Federal Register 2010, 2011, 2012, 2013, 2014

...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...

2011-05-20

316

Statistical properties of contact vectors  

NASA Astrophysics Data System (ADS)

We study the statistical properties of contact vectors, a construct to characterize a protein's structure. The contact vector of an N-residue protein is a list of N integers ni, representing the number of residues in contact with residue i. We study analytically (at mean-field level) and numerically the amount of structural information contained in a contact vector. Analytical calculations reveal that a large variance in the contact numbers reduces the degeneracy of the mapping between contact vectors and structures. Exact enumeration for lengths up to N=16 on the three-dimensional cubic lattice indicates that the growth rate of number of contact vectors as a function of N is only 3% less than that for contact maps. In particular, for compact structures we present numerical evidence that, practically, each contact vector corresponds to only a handful of structures. We discuss how this information can be used for better structure prediction.

Kabakçio?lu, A.; Kanter, I.; Vendruscolo, M.; Domany, E.

2002-04-01

317

Statistical properties of contact vectors.  

PubMed

We study the statistical properties of contact vectors, a construct to characterize a protein's structure. The contact vector of an N-residue protein is a list of N integers n(i), representing the number of residues in contact with residue i. We study analytically (at mean-field level) and numerically the amount of structural information contained in a contact vector. Analytical calculations reveal that a large variance in the contact numbers reduces the degeneracy of the mapping between contact vectors and structures. Exact enumeration for lengths up to N=16 on the three-dimensional cubic lattice indicates that the growth rate of number of contact vectors as a function of N is only 3% less than that for contact maps. In particular, for compact structures we present numerical evidence that, practically, each contact vector corresponds to only a handful of structures. We discuss how this information can be used for better structure prediction. PMID:12005870

Kabakçioglu, A; Kanter, I; Vendruscolo, M; Domany, E

2002-04-01

318

Crystal structures of tRNA-guanine transglycosylase (TGT) in complex with novel and potent inhibitors unravel pronounced induced-fit adaptations and suggest dimer formation upon substrate binding.  

PubMed

The bacterial tRNA-guanine transglycosylase (TGT) is a tRNA modifying enzyme catalyzing the exchange of guanine 34 by the modified base preQ1. The enzyme is involved in the infection pathway of Shigella, causing bacterial dysentery. As no crystal structure of the Shigella enzyme is available the homologous Zymomonas mobilis TGT was used for structure-based drug design resulting in new, potent, lin-benzoguanine-based inhibitors. Thorough kinetic studies show size-dependent inhibition of these compounds resulting in either a competitive or non-competitive blocking of the base exchange reaction in the low micromolar range. Four crystal structures of TGT-inhibitor complexes were determined with a resolution of 1.58-2.1 A. These structures give insight into the structural flexibility of TGT necessary to perform catalysis. In three of the structures molecular rearrangements are observed that match with conformational changes also noticed upon tRNA substrate binding. Several water molecules are involved in these rearrangement processes. Two of them demonstrate the structural and catalytic importance of water molecules during TGT base exchange reaction. In the fourth crystal structure the inhibitor unexpectedly interferes with protein contact formation and crystal packing. In all presently known TGT crystal structures the enzyme forms tightly associated homodimers internally related by crystallographic symmetry. Upon binding of the fourth inhibitor the dimer interface, however, becomes partially disordered. This result prompted further analyses to investigate the relevance of dimer formation for the functional protein. Consultation of the available TGT structures and sequences from different species revealed structural and functional conservation across the contacting residues. This suggests that bacterial and eukaryotic TGT could possibly act as homodimers in catalysis. It is hypothesized that one unit of the dimer performs the catalytic reaction whereas the second is required to recognize and properly orient the bound tRNA for the catalytic reaction. PMID:17524419

Stengl, Bernhard; Meyer, Emmanuel A; Heine, Andreas; Brenk, Ruth; Diederich, François; Klebe, Gerhard

2007-07-13

319

Missing Person Inquiry and Confidential Contact Information Form  

E-print Network

is considered missing. Law enforcement officials (including campus police) also will be notified of a student the investigation considerably. BE AWARE THAT IF YOU ARE A MINOR (UNDER 18 AND NOT EMANCIPATED), YOUR PARENT_______________ First, middle, last If applicable Relation to you: ____________________________________________ Address

Swaddle, John

320

/Au Back Contacts  

NASA Astrophysics Data System (ADS)

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.

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

2014-08-01

321

Contact dynamics math model  

NASA Technical Reports Server (NTRS)

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.

Glaese, John R.; Tobbe, Patrick A.

1986-01-01

322

[Contact allergy to cosmetics].  

PubMed

This article gives the results of contact allergic reactions to cosmetics seen between 1985 and 1990 (462 patients investigated) and between 1991 and 1996 (486 patients investigated). Perfume components remain the most frequently occurring allergens in cosmetics. They are followed by preservative agents, a class within which important shifts have occurred over time (e.g. as with the isothiazolinone mixture). Excipients and certainly emulsifiers (e.g. cocamidopropylbetaine) are potentially not only irritants but also allergens. Among the "active" or category-specific ingredients, oxidative hair dyes, based on paraphenylenediamine and derivatives, and nail care products, based on (meth)acrylates are particularly apt to cause professional dermatoses. Finally, the share of sunscreens as cosmetic allergens remains limited, which may well be because a contact or photocontactallergy is often not recognized since the differential diagnosis with a primary sun intolerance is not always obvious. PMID:9479432

Goossens, A; Merckx, L

1997-12-01

323

Contact stress sensor  

SciTech Connect

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.

Kotovsky, Jack

2014-02-11

324

Contact stress sensor  

DOEpatents

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.

Kotovsky, Jack (Oakland, CA)

2012-02-07

325

Measuring the specific contact resistance of contacts to semiconductor nanowires  

NASA Astrophysics Data System (ADS)

Ohmic contacts to semiconductor nanowires are essential components of many new nanoscale electronic devices. Equations for extracting specific contact resistance (or contact resistivity) from several different test structures have been developed by modeling the metal/semiconductor contact as a transmission line, leading to the development of equations analogous to those used for planar contacts. The advantages and disadvantages of various test structures are discussed. To fabricate test structures using a convenient four-point approach, silicon nanowires have been aligned using field-assisted assembly and contacts fabricated. Finally, specific contact resistances near 5 × 10 -4 ? cm 2 have been measured for Ti/Au contacts to p-type Si nanowires with diameters of 78 and 104 nm.

Mohney, S. E.; Wang, Y.; Cabassi, M. A.; Lew, K. K.; Dey, S.; Redwing, J. M.; Mayer, T. S.

2005-02-01

326

Contact Sensing: A Sequential Decision Approach to Sensing Manipulation Contact  

E-print Network

This paper describes a new statistical, model-based approach to building a contact state observer. The observer uses measurements of the contact force and position, and prior information about the task encoded in a ...

Eberman, Brian Scott

1995-05-01

327

Environmental airborne contact dermatoses.  

PubMed

This chapter is complementary to Chapter 4 published in the same series. Airborne contact dermatitis (ABCD) is considered a prototype in the field of environmental dermatology. It is often underestimated in most textbooks of general dermatology, despite its frequent occurrence in daily life. ABCD may be irritant, allergic, phototoxic, or photoallergic. Airborne contact urticaria is another example. A particular clinical aspect is the "head and neck dermatitis", which occurs in atopic adult patients. Occupational ABCD represents a most difficult issue in terms of diagnostic procedures. It is obvious that non-occupational ABCD cases involve similar problems, usually easier to solve, and our comments refer to both conditions. Two examples of potentially airborne skin infections (e.g., anthrax and Ebola virus hemorrhagic fever) are also described because they are closely related to the same problematics. A new example of airborne irritant contact dermatitis, not reported so far, is linked with the use of continuous airway pressure in the treatment of obstructive sleep apnea. PMID:25252746

Lachapelle, Jean-Marie

2014-01-01

328

Pediatric contact dermatitis.  

PubMed

Allergic contact dermatitis (ACD) in children, until recently, was considered rare. ACD was considered as a disorder of the adult population and children were thought to be spared due to a lack of exposure to potential allergens and an immature immune system. Prevalence of ACD to even the most common allergens in children, like poison ivy and parthenium, is relatively rare as compared to adults. However, there is now growing evidence of contact sensitization of the pediatric population, and it begins right from early childhood, including 1-week-old neonates. Vaccinations, piercing, topical medicaments and cosmetics in younger patients are potential exposures for sensitization. Nickel is the most common sensitizer in almost all studies pertaining to pediatric contact dermatitis. Other common allergens reported are cobalt, fragrance mix, rubber, lanolin, thiomersol, neomycin, gold, mercapto mix, balsum of Peru and colophony. Different factors like age, sex, atopy, social and cultural practices, habit of parents and caregivers and geographic changes affect the patterns of ACD and their variable clinical presentation. Patch testing should be considered not only in children with lesions of a morphology suggestive of ACD, but in any child with dermatitis that is difficult to control. PMID:20826990

Sharma, Vinod K; Asati, Dinesh P

2010-01-01

329

Human Skin Absorption and Metabolism of the Contact Allergens, Cinnamic Aldehyde, and Cinnamic Alcohol  

Microsoft Academic Search

trans-Cinnamaldehyde and trans-cinnamic alcohol have been commonly reported to cause allergic contact dermatitis (ACD) in humans. Cinnamaldehyde is a more potent skin sensitizer than cinnamic alcohol. It has been hypothesized that cinnamic alcohol is a “prohapten” that requires metabolic activation, presumably by oxidoreductase enzymes such as alcohol dehydrogenase (ADH) or cytochrome P450 2E1 (CYP2E1), to the protein-reactive cinnamaldehyde (a hapten).

Camilla K. Smith; Caroline A. Moore; Eiram N. Elahi; Alan T. S. Smart; Sharon A. M. Hotchkiss

2000-01-01

330

Surface coating for blood-contacting devices  

NASA Astrophysics Data System (ADS)

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.

Nair, Ajit Kumar Balakrishnan

331

Research and Enterprise Contacts R&E Contacts 25th  

E-print Network

Research and Enterprise Contacts R&E Contacts ­ 25th June 2014 NB: All above telephone numbers have prefix of 87 unless marked otherwise (67) G:/Shared/R&E Contact docs Subject Area School Research Development Research Finance R&E Co-ordinator Arts & Humanities English Amelia Wakeford a

Sussex, University of

332

Electroless copper contacts for low concentration silicon solar cells  

NASA Astrophysics Data System (ADS)

The purpose of this work was to form highly conductive and low cost copper contacts on shallow and hence optically thin p-n junctions (<0.4?m deep) on a randomly textured solar cells for low concentration PV (LCPV) module. At first, window formation process in SiNx by femtosecond UV laser pulse ablation on the textured surface was introduced. Then nickel silicide contacts were formed and subsequent contact thickening was performed by electroless copper plating in an industrially feasible way. Characteristics of finished solar cells were investigated in this work. The cells were successfully implemented into the low concentration (C=15x) PV module.

Janušonis, Julius; Galdikas, Algirdas; Juzumas, Valdemaras; JaraminÄ--, Lina; Lukštaraupis, Tomas; Andrijauskas, Darius; JanušonienÄ--, Vida; Janušonis, Darius; Ulbikas, Juras

2012-10-01

333

Antistiction technique using elastomer contact structure in woven electronic textiles  

NASA Astrophysics Data System (ADS)

In this paper, we present an antistiction technique using an elastomer contact structure in woven electronic textiles (e-textiles). A coating of poly(3,4-ethylenedioxythiophene):poly(4-styrene sulfonate) (PEDOT:PSS) in the form of a solid conductive film on a hemispherical silicone elastomer structure is employed in creating an electrical circuit embedded into the fabric of a woven e-textile, where the contact structure reduces the contact area and capillary force generated by the moisture in air between weft and warp ribbons. Stiction occurs between a weft and a warp without the contact structure under an RH of 80%, and the detachment of the stuck ribbon requires a delamination load of about 0.2 N. On the other hand, in the case of contact between the contact structure and the ribbon coated with plain PEDOT:PSS, stiction does not occur as the relative humidity increases from 20 to 80%.

Yamashita, Takahiro; Takamatsu, Seiichi; Miyake, Koji; Itoh, Toshihiro

2014-01-01

334

Contact Sport Concussion Incidence  

PubMed Central

Reference/Citation: Koh JO, Cassidy JD, Watkinson EJ. Incidence of concussion in contact sports: a systematic review of the evidence. Brain Inj.20031790191712963556. Clinical Question: What is the incidence of concussion in various contact sports? Data Sources: Studies for the review were found through a MEDLINE search (1985–2000) and by gathering and reviewing older articles referenced in the searched articles. The main terms that were included in the search were brain injuries, brain concussion, and incidence. Text words that were also included were mild traumatic brain injury, concussion, incidence, injury, and head injury, along with the names of 8 contact sports ( American football, boxing, ice hockey, judo, karate, tae kwon do, rugby, and soccer). Study Selection: For this review, concussion was defined as “a mild brain injury resulting from a direct blow to the head resulting in physiological changes in brain function.” Cohort studies with documented incidence of concussion in athletes from 8 identified contact sports were the target of the search. All studies of male and female athletes in any of the 8 contact sports, including practices and games and regardless of level of competition, were included in the study search. Possible articles for review were identified through a 3-step screening process. Article titles were initially screened by one of the authors. If the title seemed to be relevant to the purpose of the review, the abstract of the article was then screened for inclusion/exclusion criteria as the second step. To be included, studies had to relate to the incidence of injury to the head and brain, report results relevant to concussion, involve 1 of the 8 identified contact sports, and be published between 1985 and 2000. All systematic reviews about mild traumatic brain injury (TBI) or concussion were also included. Studies were excluded if they discussed concussion due to whiplash injury or concussion associated with spinal cord injury, facial bone fracture, or soft tissue injuries; if they reported prevalence, rather than incidence, of concussion; if they addressed chronic TBI; if they comprised case reports or letters to the editor; or if they lacked a denominator to determine risk rates. Finally, relevant and unknown articles from the abstract screening were reviewed again for the inclusion and exclusion criteria by an independent, outside party. Data Extraction: A general methodologic criteria design was used to critically appraise all articles that met the inclusion and exclusion criteria. This design appraised 11 study design and reporting criteria. In order for an article to be accepted into the systematic review, it had to meet at least the 5 mandatory criteria: description of the source population, appropriate description of inclusion and exclusion criteria, verifiable results from the raw data, differentiation of the incidence of injury between practice and game settings, and adequately measured denominator of population or person-time at risk. For each individual study, the 5 mandatory criteria listed above were rated with regard to whether they were included or addressed in the paper ( yes), were missing from the paper ( no), or were included but not described fully or in a way characterized by sound quality ( substandard). If any of the 5 mandatory criteria were rated no, the article was not evaluated any further. Data taken from these articles included sex, types of sessions in which concussion occurred, and numbers defining incidence of concussion within a contact sport. In some studies, rates were recalculated from the raw data in order to check accuracy, or if they were not presented in the published material, rates were calculated. These rates were recalculated with the denominator presented in the original study, athletes at risk for injury or time at risk for injury. Athlete-exposure was not defined in the review but is commonly used as the denominator in epidemiologic studies and represents one time in which an athlete takes part in a game or practice that expo

Tommasone, Beth A; Valovich McLeod, Tamara C

2006-01-01

335

Graphdiyne-metal contacts and graphdiyne transistors.  

PubMed

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

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

2015-01-22

336

Discovery of two new classes of potent monoamine oxidase-B inhibitors by tricky chemistry.  

PubMed

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

Cagide, F; Silva, T; Reis, J; Gaspar, A; Borges, F; Gomes, L R; Low, J N

2015-02-01

337

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

338

LETTER doi:10.1038/nature13601 Broad and potent HIV-1 neutralization by a human  

E-print Network

LETTER doi:10.1038/nature13601 Broad and potent HIV-1 neutralization by a human antibody that binds- ability on HIV Env, which serum analysis indicates to be commonly elicited by natural infection. Binding-based approaches to immunotherapies, prophylaxis and vaccine design. Induction of a potent neutralizing antibody

Cai, Long

339

Ribosome-inactivating proteins: potent poisons and molecular tools.  

PubMed

Ribosome-inactivating proteins (RIPs) were first isolated over a century ago and have been shown to be catalytic toxins that irreversibly inactivate protein synthesis. Elucidation of atomic structures and molecular mechanism has revealed these proteins to be a diverse group subdivided into two classes. RIPs have been shown to exhibit RNA N-glycosidase activity and depurinate the 28S rRNA of the eukaryotic 60S ribosomal subunit. In this review, we compare archetypal RIP family members with other potent toxins that abolish protein synthesis: the fungal ribotoxins which directly cleave the 28S rRNA and the newly discovered Burkholderia lethal factor 1 (BLF1). BLF1 presents additional challenges to the current classification system since, like the ribotoxins, it does not possess RNA N-glycosidase activity but does irreversibly inactivate ribosomes. We further discuss whether the RIP classification should be broadened to include toxins achieving irreversible ribosome inactivation with similar turnovers to RIPs, but through different enzymatic mechanisms. PMID:24071927

Walsh, Matthew J; Dodd, Jennifer E; Hautbergue, Guillaume M

2013-11-15

340

Iota-Carrageenan is a potent inhibitor of rhinovirus infection  

PubMed Central

Background Human rhinoviruses (HRVs) are the predominant cause of common cold. In addition, HRVs are implicated in the worsening of COPD and asthma, as well as the loss of lung transplants. Despite significant efforts, no anti-viral agent is approved for the prevention or treatment of HRV-infection. Results In this study we demonstrate that Iota-Carrageenan, a sulphated polysaccharide derived from red seaweed, is a potent anti-rhinoviral substance in-vitro. Iota-Carrageenan reduces HRV growth and inhibits the virus induced cythopathic effect of infected HeLa cells. In addition, Iota-Carrageenan effectively prevents the replication of HRV1A, HRV2, HRV8, HRV14, HRV16, HRV83 and HRV84 in primary human nasal epithelial cells in culture. The data suggest that Iota-Carrageenan acts primarily by preventing the binding or the entry of virions into the cells. Conclusion Since HRV infections predominately occur in the nasal cavity and the upper respiratory tract, a targeted treatment with a product containing Iota-Carrageenan is conceivable. Clinical trials are needed to determine whether Iota-Carrageenan-based products are effective in the treatment or prophylaxis of HRV infections. PMID:18817582

Grassauer, Andreas; Weinmuellner, Regina; Meier, Christiane; Pretsch, Alexander; Prieschl-Grassauer, Eva; Unger, Hermann

2008-01-01

341

microRNA-101 is a potent inhibitor of autophagy.  

PubMed

Autophagy is an evolutionarily conserved mechanism of cellular self-digestion in which proteins and organelles are degraded through delivery to lysosomes. Defects in this process are implicated in numerous human diseases including cancer. To further elucidate regulatory mechanisms of autophagy, we performed a functional screen in search of microRNAs (miRNAs), which regulate the autophagic flux in breast cancer cells. In this study, we identified the tumour suppressive miRNA, miR-101, as a potent inhibitor of basal, etoposide- and rapamycin-induced autophagy. Through transcriptome profiling, we identified three novel miR-101 targets, STMN1, RAB5A and ATG4D. siRNA-mediated depletion of these genes phenocopied the effect of miR-101 overexpression, demonstrating their importance in autophagy regulation. Importantly, overexpression of STMN1 could partially rescue cells from miR-101-mediated inhibition of autophagy, indicating a functional importance for this target. Finally, we show that miR-101-mediated inhibition of autophagy can sensitize breast cancer cells to 4-hydroxytamoxifen (4-OHT)-mediated cell death. Collectively, these data establish a novel link between two highly important and rapidly growing research fields and present a new role for miR-101 as a key regulator of autophagy. PMID:21915098

Frankel, Lisa B; Wen, Jiayu; Lees, Michael; Høyer-Hansen, Maria; Farkas, Thomas; Krogh, Anders; Jäättelä, Marja; Lund, Anders H

2011-11-16

342

Marizomib, a potent second generation proteasome inhibitor from natural origin.  

PubMed

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

Ma, Long; Diao, Aipo

2014-11-14

343

Potent Antimalarial Activity of Histone Deacetylase Inhibitor Analogues? †  

PubMed Central

The malaria parasite Plasmodium falciparum has at least five putative histone deacetylase (HDAC) enzymes, which have been proposed as new antimalarial drug targets and may play roles in regulating gene transcription, like the better-known and more intensively studied human HDACs (hHDACs). Fourteen new compounds derived from l-cysteine or 2-aminosuberic acid were designed to inhibit P. falciparum HDAC-1 (PfHDAC-1) based on homology modeling with human class I and class II HDAC enzymes. The compounds displayed highly potent antiproliferative activity against drug-resistant (Dd2) or drug sensitive (3D7) strains of P. falciparum in vitro (50% inhibitory concentration of 13 to 334 nM). Unlike known hHDAC inhibitors, some of these new compounds were significantly more toxic to P. falciparum parasites than to mammalian cells. The compounds inhibited P. falciparum growth in erythrocytes at both the early and late stages of the parasite's life cycle and caused altered histone acetylation patterns (hyperacetylation), which is a marker of HDAC inhibition in mammalian cells. These results support PfHDAC enzymes as being promising targets for new antimalarial drugs. PMID:18212103

Andrews, K. T.; Tran, T. N.; Lucke, A. J.; Kahnberg, P.; Le, G. T.; Boyle, G. M.; Gardiner, D. L.; Skinner-Adams, T. S.; Fairlie, D. P.

2008-01-01

344

Potent antihypertensive action of dietary flaxseed in hypertensive patients.  

PubMed

Flaxseed contains ?-3 fatty acids, lignans, and fiber that together may provide benefits to patients with cardiovascular disease. Animal work identified that patients with peripheral artery disease may particularly benefit from dietary supplementation with flaxseed. Hypertension is commonly associated with peripheral artery disease. The purpose of the study was to examine the effects of daily ingestion of flaxseed on systolic (SBP) and diastolic blood pressure (DBP) in peripheral artery disease patients. In this prospective, double-blinded, placebo-controlled, randomized trial, patients (110 in total) ingested a variety of foods that contained 30 g of milled flaxseed or placebo each day over 6 months. Plasma levels of the ?-3 fatty acid ?-linolenic acid and enterolignans increased 2- to 50-fold in the flaxseed-fed group but did not increase significantly in the placebo group. Patient body weights were not significantly different between the 2 groups at any time. SBP was ? 10 mm Hg lower, and DBP was ? 7 mm Hg lower in the flaxseed group compared with placebo after 6 months. Patients who entered the trial with a SBP ? 140 mm Hg at baseline obtained a significant reduction of 15 mm Hg in SBP and 7 mm Hg in DBP from flaxseed ingestion. The antihypertensive effect was achieved selectively in hypertensive patients. Circulating ?-linolenic acid levels correlated with SBP and DBP, and lignan levels correlated with changes in DBP. In summary, flaxseed induced one of the most potent antihypertensive effects achieved by a dietary intervention. PMID:24126178

Rodriguez-Leyva, Delfin; Weighell, Wendy; Edel, Andrea L; LaVallee, Renee; Dibrov, Elena; Pinneker, Reinhold; Maddaford, Thane G; Ramjiawan, Bram; Aliani, Michel; Guzman, Randolph; Pierce, Grant N

2013-12-01

345

A Synthetic Chalcone as a Potent Inducer of Glutathione Biosynthesis  

PubMed Central

Chalcones continue to attract considerable interest due to their anti-inflammatory and antiangiogenic properties. We recently reported the ability of 2?,5?-dihydroxychalcone (2?,5?-DHC) to induce both breast cancer resistance protein-mediated export of glutathione (GSH) and c-Jun N-terminal kinase-mediated increased intracellular GSH levels. Herein, we report a structure–activity relationship study of a series of 30 synthetic chalcone derivatives with hydroxyl, methoxyl, and halogen (F and Cl) substituents and their ability to increase intracellular GSH levels. This effect was drastically improved with one or two electrowithdrawing groups on phenyl ring B and up to three methoxyl and/or hydroxyl groups on phenyl ring A. The optimal structure, 2-chloro-4?,6?-dimethoxy-2?-hydroxychalcone, induced both a potent NF-E2-related factor 2-mediated transcriptional response and an increased formation of glutamate cysteine ligase holoenzyme, as shown using a human breast cancer cell line stably expressing a luciferase reporter gene driven by antioxidant response elements. PMID:22239485

Kachadourian, Remy; Day, Brian J.; Pugazhenti, Subbiah; Franklin, Christopher C.; Genoux-Bastide, Estelle; Mahaffey, Gregory; Gauthier, Charlotte; Di Pietro, Attilio; Boumendjel, Ahcène

2014-01-01

346

Novel potent inhibitors of A. thaliana cytokinin oxidase/dehydrogenase.  

PubMed

The synthesis of a new group of 2-X-6-anilinopurines, including compounds with potential cytokinin-like activities, with various substitutions (X=H, halogen, amino, methylthio or nitro) on the phenyl ring is described. The prepared compounds have been characterized using standard physico-chemical methods, and the influence of individual substituents on biological activity has been compared in three different bioassays, based on the stimulation of tobacco callus growth, retention of chlorophyll in excised wheat leaves and the dark induction of betacyanin synthesis in Amaranthus cotyledons. The biological activity of the prepared compounds was also assessed in receptor assays, in which the ability of the compounds to activate the cytokinin receptors AHK3 and AHK4/CRE1 was studied. Finally, the interactions of the compounds with the Arabidopsis cytokinin oxidase/dehydrogenase AtCKX2 (heterologously expressed) were investigated. Systematic testing led to the identification of two very potent inhibitors of AtCKX2: 2-chloro-6-(3-methoxyphenyl)aminopurine and 2-fluoro-6-(3-methoxyphenyl)aminopurine. PMID:18818088

Zatloukal, Marek; Gemrotová, Markéta; Dolezal, Karel; Havlícek, Libor; Spíchal, Lukás; Strnad, Miroslav

2008-10-15

347

Contact Lens Use in Industry  

MedlinePLUS

... supervisors should be informed of employees who wear contact lenses. 7. Medical and first aid personnel should be trained in the proper procedures and equipment for removing both hard and soft contacts from conscious and unconscious workers. ...

348

PROCEDURE CARDS EMERGENCY CONTACT INFORMATION  

E-print Network

or UD Public Safety for emergency assistance 4. If imminent danger exists activate building alarm Contact UD Public Safety for emergency medical assistance or contact Supervisor, Instructor, or EHS EYE UD Public Safety for emergency assistance CHEMICAL SPILL/ SPLASH #12;

Firestone, Jeremy

349

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,

350

Tax Forms  

NSDL National Science Digital Library

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.

Ledvina, Mary J.

1997-01-01

351

Correlation of contact deformation with contact electrification of identical materials  

NASA Astrophysics Data System (ADS)

We report an experimental study on the contact electrification produced by two chemically identical glass plates under different contact forces. For the given plate sizes, the mean value of the surface charge density is independent of the contact force, but the standard deviation of the surface charge density increases with increasing contact force, which indicates that the magnitude of charge transfer is enhanced with increasing contact force. The contact between plates of different sizes leads to the systematic transfer of charge in one direction. To understand this effect, finite element modelling was carried out, which shows that the contact between plates of different sizes leads to different in-plane strains developing in the two plates. The surface charge density from contact electrification correlates with the difference in the in-plane strain between the contacted plates. The results suggest that the in-plane strain difference between contact surfaces plays an essential role in contact electrification and may be a key driving force for the charge transfer between chemically identical surfaces.

Xie, L.; He, P. F.; Zhou, J.; Lacks, D. J.

2014-05-01

352

Contact position sensor using constant contact force control system  

NASA Technical Reports Server (NTRS)

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).

Sturdevant, Jay (Inventor)

1995-01-01

353

Adhesive Contact Sweeper  

NASA Technical Reports Server (NTRS)

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.

Patterson, Jonathan D.

1993-01-01

354

Pitstop 2 Is a Potent Inhibitor of Clathrin-Independent Endocytosis  

PubMed Central

Clathrin independent endocytosis (CIE) is a form of endocytosis present in all cells that mediates the entry of nutrients, macromolecules and membrane proteins into cells. When compared to clathrin-dependent endocytosis (CDE), however, much less is known about the machinery involved in forming CIE endosomes. One way to distinguish CIE from CDE has been to deplete cells of coat proteins involved in CDE such as clathrin or the dynamin GTPase, leading to a block of CDE but not CIE. A drawback of such genetic manipulations is that depletion of proteins important for mediating CDE over a period of days can have complex indirect effects on cellular function. The identification of chemical compounds that specifically and rapidly block CDE or CIE would facilitate the determination of whether a process involved CDE or CIE. To date, all of those compounds have targeted CDE. Dynasore and the dynoles specifically target and block dynamin activity thus inhibiting CDE but not most forms of CIE. Recently, a new compound called pitstop 2 was identified as an inhibitor of the interaction of amphiphysin with the amino terminal domain of clathrin, and shown to inhibit CDE in cells. Here we show that pitstop 2 is also a potent inhibitor of CIE. The effects of pitstop 2 are not restricted to inhibition of clathrin since knockdown of clathrin fails to rescue the inhibition of endocytosis of CIE proteins by the drug. Thus pitstop 2 has additional cellular targets besides the amino terminal domain of clathrin and thus cannot be used to distinguish CIE from CDE. PMID:23029248

Dutta, Dipannita; Williamson, Chad D.; Cole, Nelson B.; Donaldson, Julie G.

2012-01-01

355

Discovery of Potent Broad Spectrum Antivirals Derived from Marine Actinobacteria  

PubMed Central

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

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

356

Matrices of Physiologic Stiffness Potently Inactivate Idiopathic Pulmonary Fibrosis Fibroblasts  

PubMed Central

Fibroblasts from patients with idiopathic pulmonary fibrosis (IPF) have been shown to differ from normal lung fibroblasts in functional behaviors that contribute to the pathogenesis of IPF, including the expression of contractile proteins and proliferation, but how such behaviors vary in matrices with stiffness matched to normal and fibrotic lung tissue remains unknown. Here, we tested whether pathologic changes in matrix stiffness control IPF and normal lung tissue–derived fibroblast functions, and compared the relative efficacy of mechanical cues to an antifibrotic lipid mediator, prostaglandin E2 (PGE2). Fibroblasts were grown on collagen I–coated glass or hydrogel substrates of discrete stiffnesses, spanning the range of normal and fibrotic lung tissue. Traction microscopy was used to quantify contractile function. The CyQuant Cell Proliferation Assay (Invitrogen, Carlsbad, CA) was used to assess changes in cell number, and PGE2 concentrations were measured by ELISA. We confirmed differences in proliferation and PGE2 synthesis between IPF and normal tissue–derived fibroblasts on rigid substrates. However, IPF fibroblasts remained highly responsive to changes in matrix stiffness, and both proliferative and contractile differences between IPF and normal fibroblasts were ablated on physiologically soft matrices. We also confirmed the relative resistance of IPF fibroblasts to PGE2, while demonstrating that decreases in matrix stiffness and the inhibition of Rho kinase both potently attenuate contractile function in IPF-derived fibroblasts. We conclude that pathologic changes in the mechanical environment control important IPF fibroblast functions. Understanding how mechanical cues control fibroblast function may offer new opportunities for targeting these cells, even when they are resistant to antifibrotic pharmacological agents or biological mediators. PMID:23258227

Marinkovi?, Aleksandar; Liu, Fei

2013-01-01

357

Allergic Contact Dermatitis  

PubMed Central

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

Nelson, Jenny L.

2010-01-01

358

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

E-print Network

Reclassification Steve Marley Marybeth Wilcox Posting Student Jobs Christie Gilliland Steve Marley or MarybethTOPIC 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

359

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

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

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

360

[News on occupational contact dermatitis].  

PubMed

Contact dermatitis--irritant contact dermatitis, allergic contact dermatitis and protein contact dermatitis--are the most common occupational skin diseases, most often localized to the hands. Contact urticaria is rarer The main occupational irritants are wet work, detergents and disinfectants, cutting oils, and solvents. The main occupational allergens are rubber additives, metals (chromium, nickel, cobalt), plastics (epoxy resins, acrylic), biocides and plants. Diagnosis is based on clinical examination, medical history and allergy testing. For a number of irritating or sensitizing agents, irritant or allergic dermatitis can be notified as occupational diseases. The two main prevention measures are reducing skin contact with irritants and complete avoidance of skin contact with offending allergens. PMID:24851370

Crépy, Marie-Noëlle; Bensefa-Colas, Lynda

2014-03-01

361

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

DOEpatents

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.

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

2001-01-01

362

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

DOEpatents

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.

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

2000-01-01

363

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: ...

364

National Cancer Institute - CPFP Intranet - Forms  

Cancer.gov

Skip navigation. CPFP Intranet Responsibilities Advisory Board Outside Activities Manuscripts, Abstracts and Presentations Ethics and Ethical Issues Forms and Schedules Travel Training Reports General Information Employment Resources Home Page Contact

365

Clostridium perfringens epsilon toxin: The third most potent bacterial toxin known.  

PubMed

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

Alves, Guilherme Guerra; Machado de Ávila, Ricardo Andrez; Chávez-Olórtegui, Carlos Delfin; Lobato, Francisco Carlos Faria

2014-12-01

366

The 2'-Trifluoromethyl Analogue of Indomethacin Is a Potent and Selective COX-2 Inhibitor.  

PubMed

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

Blobaum, Anna L; Uddin, Md Jashim; Felts, Andrew S; Crews, Brenda C; Rouzer, Carol A; Marnett, Lawrence J

2013-05-01

367

Structural Basis of Potent and Broad HIV-1 Fusion Inhibitor CP32M*  

PubMed Central

CP32M is a newly designed peptide fusion inhibitor possessing potent anti-HIV activity, especially against T20-resistant HIV-1 strains. In this study, we show that CP32M can efficiently inhibit a large panel of diverse HIV-1 variants, including subtype B?, CRF07_BC, and CRF01_AE recombinants and naturally occurring or induced T20-resistant viruses. To elucidate its mechanism of action, we determined the crystal structure of CP32M complexed with its target sequence. Differing from its parental peptide, CP621-652, the 621VEWNEMT627 motif of CP32M folds into two ?-helix turns at the N terminus of the pocket-binding domain, forming a novel layer in the six-helix bundle structure. Prominently, the residue Asn-624 of the 621VEWNEMT627 motif is engaged in the polar interaction with a hydrophilic ridge that borders the hydrophobic pocket on the N-terminal coiled coil. The original inhibitor design of CP32M provides several intra- and salt bridge/hydrogen bond interactions favoring the stability of the helical conformation of CP32M and its interactions with N-terminal heptad repeat (NHR) targets. We identified a novel salt bridge between Arg-557 on the NHR and Glu-648 of CP32M that is critical for the binding of CP32M and resistance against the inhibitor. Therefore, our data present important information for developing novel HIV-1 fusion inhibitors for clinical use. PMID:22679024

Yao, Xue; Chong, Huihui; Zhang, Chao; Qiu, Zonglin; Qin, Bo; Han, Ruiyun; Waltersperger, Sandro; Wang, Meitian; He, Yuxian; Cui, Sheng

2012-01-01

368

Supramolecular assembly of multifunctional maspin-mimetic nanostructures as a potent peptide-based angiogenesis inhibitor.  

PubMed

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

Zha, R Helen; Sur, Shantanu; Boekhoven, Job; Shi, Heidi Y; Zhang, Ming; Stupp, Samuel I

2015-01-15

369

Glycosylated Enfuvirtide: A Long-Lasting Glycopeptide with Potent Anti-HIV Activity.  

PubMed

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

Cheng, Shuihong; Chang, Xuesong; Wang, Yan; Gao, George F; Shao, Yiming; Ma, Liying; Li, Xuebing

2015-02-12

370

Immunopotentiating nano-chitosan as potent vaccine carter for efficacious prophylaxis of filarial antigens.  

PubMed

Lymphatic filariasis (LF), a morbid vector-borne parasitic infection affects millions in tropical areas. Complete eradication can only be achieved by the development of a potent vaccine. Among the various filarial antigens that have been characterized, antigens Brugia malayi thioredoxin (TRX) and abundant larval transcript (ALT) have produced recognizable level of protection in Jirds, thereby evidenced to be good vaccine candidates. In this study an attempt was made to enhance their immunoprophylactic activity by encapsulating them in natural polysaccharide chitosan forming nanospheres (CN). High encapsulation efficiency for TRX (93%) in CN (TCN) and ALT-2 (90%) in CN (ACN) was achieved. Morphological studies confirmed the spherical and uniform distribution of nanospheres to be 220nm. The electrostatic interaction between chitosan and the antigens were confirmed using differential scanning calorimetry and FT-IR. The study revealed the immunostimulatory property of chitosan providing enhanced level of proliferation for encapsulated antigens in peripheral blood mononuclear cells from endemic normal personals, at low concentration (TCN mean stimulation index (SI)=4.23±0.15 and ACN (SI)=4.05±0.33) compared to stimulation obtained by antigens alone. Hence, our study demonstrated that natural macromolecule derived CN can be used as efficacious immunostimulatory vaccine carter for LF thereby diminishing pathological sequel. PMID:25433130

Malathi, Balasubramaniyan; Mona, Santhanam; Thiyagarajan, Devasena; Kaliraj, Perumal

2015-02-01

371

Fulvene-5 potently inhibits NADPH oxidase 4 and blocks the growth of endothelial tumors in mice  

PubMed Central

Hemangiomas are the most common type of tumor in infants. As they are endothelial cell–derived neoplasias, their growth can be regulated by the autocrine-acting Tie2 ligand angiopoietin 2 (Ang2). Using an experimental model of human hemangiomas, in which polyoma middle T–transformed brain endothelial (bEnd) cells are grafted subcutaneously into nude mice, we compared hemangioma growth originating from bEnd cells derived from wild-type, Ang2+/–, and Ang2–/– mice. Surprisingly, Ang2-deficient bEnd cells formed endothelial tumors that grew rapidly and were devoid of the typical cavernous architecture of slow-growing Ang2-expressing hemangiomas, while Ang2+/– cells were greatly impaired in their in vivo growth. Gene array analysis identified a strong downregulation of NADPH oxidase 4 (Nox4) in Ang2+/– cells. Correspondingly, lentiviral silencing of Nox4 in an Ang2-sufficient bEnd cell line decreased Ang2 mRNA levels and greatly impaired hemangioma growth in vivo. Using a structure-based approach, we identified fulvenes as what we believe to be a novel class of Nox inhibitors. We therefore produced and began the initial characterization of fulvenes as potential Nox inhibitors, finding that fulvene-5 efficiently inhibited Nox activity in vitro and potently inhibited hemangioma growth in vivo. In conclusion, the present study establishes Nox4 as a critical regulator of hemangioma growth and identifies fulvenes as a potential class of candidate inhibitor to therapeutically interfere with Nox function. PMID:19620773

Bhandarkar, Sulochana S.; Jaconi, Marisa; Fried, Levi E.; Bonner, Michael Y.; Lefkove, Benjamin; Govindarajan, Baskaran; Perry, Betsy N.; Parhar, Ravi; Mackelfresh, Jamie; Sohn, Allie; Stouffs, Michael; Knaus, Ulla; Yancopoulos, George; Reiss, Yvonne; Benest, Andrew V.; Augustin, Hellmut G.; Arbiser, Jack L.

2009-01-01

372

Fulvene-5 potently inhibits NADPH oxidase 4 and blocks the growth of endothelial tumors in mice.  

PubMed

Hemangiomas are the most common type of tumor in infants. As they are endothelial cell-derived neoplasias, their growth can be regulated by the autocrine-acting Tie2 ligand angiopoietin 2 (Ang2). Using an experimental model of human hemangiomas, in which polyoma middle T-transformed brain endothelial (bEnd) cells are grafted subcutaneously into nude mice, we compared hemangioma growth originating from bEnd cells derived from wild-type, Ang2+/-, and Ang2-/- mice. Surprisingly, Ang2-deficient bEnd cells formed endothelial tumors that grew rapidly and were devoid of the typical cavernous architecture of slow-growing Ang2-expressing hemangiomas, while Ang2+/- cells were greatly impaired in their in vivo growth. Gene array analysis identified a strong downregulation of NADPH oxidase 4 (Nox4) in Ang2+/- cells. Correspondingly, lentiviral silencing of Nox4 in an Ang2-sufficient bEnd cell line decreased Ang2 mRNA levels and greatly impaired hemangioma growth in vivo. Using a structure-based approach, we identified fulvenes as what we believe to be a novel class of Nox inhibitors. We therefore produced and began the initial characterization of fulvenes as potential Nox inhibitors, finding that fulvene-5 efficiently inhibited Nox activity in vitro and potently inhibited hemangioma growth in vivo. In conclusion, the present study establishes Nox4 as a critical regulator of hemangioma growth and identifies fulvenes as a potential class of candidate inhibitor to therapeutically interfere with Nox function. PMID:19620773

Bhandarkar, Sulochana S; Jaconi, Marisa; Fried, Levi E; Bonner, Michael Y; Lefkove, Benjamin; Govindarajan, Baskaran; Perry, Betsy N; Parhar, Ravi; Mackelfresh, Jamie; Sohn, Allie; Stouffs, Michael; Knaus, Ulla; Yancopoulos, George; Reiss, Yvonne; Benest, Andrew V; Augustin, Hellmut G; Arbiser, Jack L

2009-08-01

373

Acyclic nucleoside thiophosphonates as potent inhibitors of HIV and HBV replication.  

PubMed

9-[2-(Thiophosphonomethoxy)ethyl]adenine 3 and (R)-9-[2-(Thiophosphonomethoxy)propyl]adenine 4 were synthesized as the first thiophosphonate nucleosides bearing a sulfur atom at the ?-position of the acyclic nucleoside phosphonates PMEA and PMPA. Thiophosphonates S-PMEA 3 and S-PMPA 4 were evaluated for in vitro activity against HIV-1 (subtypes A to G), HIV-2 and HBV-infected cells, and found to exhibit potent antiretroviral activity. We showed that their diphosphate forms S-PMEApp 5 and S-PMPApp 6 are readily incorporated by wild-type (WT) HIV-1 RT into DNA and act as DNA chain terminators. Compounds 3 and 4 were evaluated for in vitro activity against a broad panel of DNA and RNA viruses and displayed beside HIV a moderate activity against herpes simplex virus and vaccinia viruses. In order to measure enzymatic stabilities of the target derivatives 3 and 4, kinetic data and decomposition pathways were studied at 37 °C in several media. PMID:21803462

Barral, Karine; Weck, Clément; Payrot, Nadine; Roux, Loic; Durafour, Céline; Zoulim, Fabien; Neyts, Johan; Balzarini, Jan; Canard, Bruno; Priet, Stéphane; Alvarez, Karine

2011-09-01

374

Potent 19-norvitamin D analogs for prostate and liver cancer therapy  

PubMed Central

The active form of vitamin D3, 1?,25(OH)2D3 or calcitriol, is known to inhibit the proliferation and invasiveness of many types of cancer cells, including prostate and liver cancer cells. These findings support the use of 1?,25(OH)2D3 for prostate and liver cancer therapy. However, 1?,25(OH)2D3 can cause hypercalcemia, thus, analogs of 1?,25(OH)2D3 that are less calcemic but exhibit potent antiproliferative activity would be attractive as therapeutic agents. We have developed 2?-functional group substituted 19-norvitamin D3 analogs with and without 14-epimerization. Among them, 2?- and 2?-(3-hydroxypropyl)-1?,25-dihydroxy-19-norvitamin D3 (MART-10 and -11, respectively) and 14-epi-2?- and 14-epi-2?-(3-hydroxypropyl)-1?,25-dihydroxy-19-norvitamin D3 (14-epi-MART-10 and 14-epi-MART-11, respectively) were found to be the most promising. In this review, we discuss the synthesis of this unique class of vitamin D analogs, the molecular mechanism of anticancer actions of vitamin D, and the biological evaluation of these analogs for potential application to the prevention and treatment of prostate and liver cancer. PMID:23157238

Kittaka, Atsushi; Yoshida, Akihiro; Chiang, Kun-Chun; Takano, Masashi; Sawada, Daisuke; Sakaki, Toshiyuki; Chen, Tai C

2013-01-01

375

Extracellular amastigotes of Trypanosoma cruzi are potent inducers of phagocytosis in mammalian cells  

PubMed Central

The protozoan parasite Trypanosoma cruzi, the aetiological agent of Chagas' disease, has two infective life cycle stages, trypomastigotes and amastigotes. While trypomastigotes actively enter mammalian cells, highly infective extracellular amastigotes (type I T. cruzi) rely on actin-mediated uptake, which is generally inefficient in non-professional phagocytes. We found that extracellular amastigotes (EAs) of T. cruzi G strain (type I), but not Y strain (type II), were taken up 100-fold more efficiently than inert particles. Mammalian cell lines showed levels of parasite uptake comparable to macrophages, and extensive actin recruitment and polymerization was observed at the site of entry. EA uptake was not dependent on parasite-secreted molecules and required the same molecular machinery utilized by professional phagocytes during large particle phagocytosis. Transcriptional silencing of synaptotagmin VII and CD63 significantly inhibited EA internalization, demonstrating that delivery of supplemental lysosomal membrane to form the phagosome is involved in parasite uptake. Importantly, time-lapse live imaging using fluorescent reporters revealed phagosome-associated modulation of phosphoinositide metabolism during EA uptake that closely resembles what occurs during phagocytosis by macrophages. Collectively, our results demonstrate that T. cruzi EAs are potent inducers of phagocytosis in non-professional phagocytes, a process that may facilitate parasite persistence in infected hosts. PMID:23241026

Fernandes, Maria Cecilia; Flannery, Andrew R; Andrews, Norma; Mortara, Renato A

2013-01-01

376

Na?-K?-ATPase, a potent neuroprotective modulator against Alzheimer disease.  

PubMed

Alzheimer disease (AD) is a neurodegenerative disorder clinically characterized by progressive cognitive and memory dysfunction, which is the most common form of dementia. Although the pathogenesis of neuronal injury in AD is not clear, recent evidences suggest that Na?-K?-ATPase plays an important role in AD, and may be a potent neuroprotective modulator against AD. This review aims to provide readers with an in-depth understanding of Na?-K?-ATPase in AD through these modulations of some factors that are as follows, which leads to the change of learning and memory in the process of AD. 1. The deficiency in Na?, K?-ATPase ?1, ?2 and ?3 isoform genes induced learning and memory deficits, and ? isoform was evidently changed in AD, revealing that Na?, K?-ATPase ? isoform genes may play an important role in AD. 2. Some factors, such as ?-amyloid, cholinergic and oxidative stress, can modulate learning and memory in AD through the mondulation of Na?-K?-ATPase activity. 3. Some substances, such as Zn, s-Ethyl cysteine, s-propyl cysteine, citicoline, rivastigmine, Vit E, memantine, tea polyphenol, curcumin, caffeine, Alpinia galanga (L.) fractions, and Bacopa monnieri could play a role in improving memory performance and exert protective effects against AD by increasing expression or activity of Na?, K?-ATPase. PMID:23033963

Zhang, Li-Nan; Sun, Yong-Jun; Pan, Shuo; Li, Jun-Xia; Qu, Yin-E; Li, Yao; Wang, Yong-Li; Gao, Zi-Bin

2013-02-01

377

Equilibrium forms of protein crystals  

NASA Astrophysics Data System (ADS)

Models for equilibrium forms of protein crystals were suggested using classical methods, such as Stranski-Kaischew's mean-separation-work method and the Gibbs-Curie-Wulff law. Although absolute bonding energies in protein crystal lattices are unknown, their relative strength was estimated from the type of lattice contacts observed in the protein x-ray structures. Equilibrium forms of ferritin crystals deduced on this basis were compared with experimental observations of Yau and Vekilov.

Nanev, Christo N.

2012-12-01

378

Laser Forming of Aerospace Alloys  

Microsoft Academic Search

Non-contact forming by application of a thermal source has been known for some time. Recently, it has been shown that much greater controllability can be introduced by replacing the thermal source with a laser. This yields a process with strong potential for application in aerospace, including the rapid manufacture of prototypes and the adjustment of misaligned components. This paper briefly

K. G. Watkins; S. P. Edwardson; J. Magee; G. Dearden; R. L. Cooke; J. Sidhu; N. J. Calder

379

Comparison of Pt-Based Ohmic Contacts with Ti-Al Ohmic Contacts for p-Type SiC  

NASA Astrophysics Data System (ADS)

In this study, two Pt-based ohmic contacts were systematically compared with a conventional Ti-Al ohmic contact on p-type 4H- and 6H-SiC substrates in terms of specific contact resistance, contact morphology, and phase chemistry. The average specific contact resistance (SCR) values measured for the Ti/Al, Pt and Pt/Si ohmic contacts on 4H-SiC were 7.0 × 10-5 ? cm2, 1.5 × 10-4 ? cm2 and 4.4 × 10-5 ? cm2, respectively. The corresponding standard deviations of the SCR values are 3.4 × 10-5 ? cm2, 3.8 × 10-5 ? cm2 and 1.3 × 10-5 ? cm2. Microstructural analysis showed that both Ti/Al and Pt ohmic contacts reacted with the SiC substrate during annealing to form several phases and a rough interface. In contrast, single-phase PtSi contacts, formed using the required thickness ratio of 1:1.32 Pt/Si, yield a smooth interface. A correlation between the electrical properties and the morphology is discussed.

Mohammad, F. A.; Cao, Y.; Chang, K.-C.; Porter, L. M.

2005-08-01

380

Nonlinear cyclical transport phenomena in copper point contacts  

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

381

Status of wraparound contact solar cells and arrays  

NASA Technical Reports Server (NTRS)

Solar cells with wraparound contacts provide the following advantages in array assembly: (1) eliminate the need for discretely formed, damage susceptible series tabs; (2) eliminate the n gap problem by allowing the use of uniform covers over the entire cell surface; (3) allow a higher packing factor by reducing the additional series spacing formly required for forming, and routing the series tab; and (4) allow the cell bonding to the interconnect system to be a single-side function wherein series contacts can be made at the same time parallel contracts are made.

Baraona, C. R.; Young, L. E.

1978-01-01

382

Permission Forms  

ERIC Educational Resources Information Center

The prevailing practice in public schools is to routinely require permission or release forms for field trips and other activities that pose potential for liability. The legal status of such forms varies, but they are generally considered to be neither rock-solid protection nor legally valueless in terms of immunity. The following case and the…

Zirkel, Perry A.

2005-01-01

383

Contact mechanics with adhesion: Interfacial separation and contact area  

E-print Network

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.

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

2008-08-26

384

Capacitive Contacts:. Making Four-Point Characterizations Without Ohmic Contacts  

NASA Astrophysics Data System (ADS)

Four-point measurements are carried out on a Hall bar using specially designed capacitive contacts, reproducing the transport characteristics Rxx measured using standard ohmic contacts. All Rxx measurements using various combinations of ohmic and capacitive contacts are in quantitative agreement, with a calibrated scaling factor arising because of the device and measurement setup capacitances. Also amplitude and phase measurements represented with the Bode plots for all combinations of ohmic and capacitive contacts are carried out and the results compare favorably with our circuit analysis.

Isik, N.; Bichler, M.; Roth, S.; Grayson, M.

385

Factors influencing bacterial adhesion to contact lenses  

PubMed Central

The process of any contact lens related keratitis generally starts with the adhesion of opportunistic pathogens to contact lens surface. This article focuses on identifying the factors which have been reported to affect bacterial adhesion to contact lenses. Adhesion to lenses differs between various genera/species/strains of bacteria. Pseudomonas aeruginosa, which is the predominant causative organism, adheres in the highest numbers to both hydrogel and silicone hydrogel lenses in vitro. The adhesion of this strain reaches maximum numbers within 1h in most in vitro studies and a biofilm has generally formed within 24 h of cells adhering to the lens surface. Physical and chemical properties of contact lens material affect bacterial adhesion. The water content of hydroxyethylmethacrylate (HEMA)-based lenses and their iconicity affect the ability of bacteria to adhere. The higher hydrophobicity of silicone hydrogel lenses compared to HEMA-based lenses has been implicated in the higher numbers of bacteria that can adhere to their surfaces. Lens wear has different effects on bacterial adhesion, partly due to differences between wearers, responses of bacterial strains and the ability of certain tear film proteins when bound to a lens surface to kill certain types of bacteria. PMID:22259220

Dutta, Debarun; Willcox, Mark

2012-01-01

386

Energetics of chlorins: a potent photosensitizer of PDT  

NASA Astrophysics Data System (ADS)

A number of derivatives of chlorin e6 (mono, di and trimethyl ethers) and purpurin-18 (monomethyl ether) potential sensitizers of PDT have been prepared and spectral-kinetic properties of their lowest electronic singlet and triplet states have been studied. The extinction of Q-band of the studied chlorins is much higher than convenient porphyrin photosensitizers and varies between 3 - 6 (DOT) 104 M-1 cm-1. The highest degree of polarization is 0.45 and related to S1-S0 transition. Quantum yields of fluorescence (rho) purpurin-18 in diethyl ether is lowest among the other studied chlorins and consists of 0.10 and decreases with increasing concentration as a result of the aggregation. The chlorin e6 derivatives have close values of quantum yields of fluorescence (0.16 - 0.18). Appreciable quantum yield of fluorescence is promising for application of chlorins for tumor detection due to photosensitizer retention in tumor tissues. The quantum yield of triplet formation (gamma) measured flash photolysis method was 0.70 - 0.76. The energy of the lowest triplet level estimated by maximum of phosphorescence band of chlorins is between 830 - 900 nm. The rate constant of oxygen quenching of triplets in solutions is one order less than diffusion rate constant. The luminescence of singlet oxygen has been observed as a result of energy transfer from triplet state of chlorins to molecular oxygen in organic solvents and deuterated water. Relative intensity of singlet oxygen luminescence 1272 nm photosensitized by different chlorins correlated with quantum yields of its triplets formation. The difference 0.05 - 0.20 between the unit and the sum of (rho) plus (gamma) for the number of chlorins has been assigned to the channel of internal conversion. The internal conversion was eliminated by deuteration of an NH group of chlorins showing that high frequency NH vibrations are responsible for radiationless deactivation of electron energy of the S1 state of chlorins. The comparison of photodynamic action chlorins and photofrin on cells level and tumors in vivo demonstrates that chlorins are more potent photosensitizers of PDT.

Losev, Anatoly P.; Nichiporovich, I. N.; Zhuravkin, Ivan N.; Zhavrid, Edvard A.

1996-04-01

387

Energetics of chlorins as potent photosensitizers of PDT  

NASA Astrophysics Data System (ADS)

A number of derivatives of chlorin e6 (mono, di and trimethyl ethers), purpurin-18 (monomethyl ether) and tetracarboxyphenylporphyrin -- potential sensitizers of PDT have been prepared and spectral-kinetic properties of their lowest electronic excited singlet and triplet states have been studied. The extinction of Q-band of studied chlorins is much higher than conventional porphyrin photosensitizers and varies between 3 - 6 multiplied by 104 M-1 cm-1. The highest degree of polarization is 0.45 and related to S1 - S0 transition. Quantum yields of fluorescence (rho) purpurin-18 in diethyl ether are lowest among other studied chlorins and consists of 0.10 and decreases with increasing concentration as a result of the aggregation. The chlorin e6 derivatives have close values of quantum yields of fluorescence (0.16 - 0.18). Appreciable quantum yield of fluorescence is promising for application of chlorins for tumor detection due to photosensitizer retention in tumor tissues. The quantum yield of triplet formation (gamma) measured flash photolysis method was 0.70 - 0.76. The energy of the lowest triplet level estimated by maximum of phosphorescence band of chlorins is between 830 - 900 nm. The rate constant of oxygen quenching of triplets in solutions is one order less than diffusion rate constant. The luminescence of singlet oxygen has been observed as a result of energy transfer from triplet state of chlorins to molecular oxygen in organic solvents and deuterated water. Relative intensity of singlet oxygen luminescence 1272 nm photosensitized by different chlorins correlated with quantum yields of its triplets formation. The difference 0.05 - 0.20 between the unit and the sum of (rho) plus (gamma) for a number of sensitizers has been assigned to the channel of internal conversion. The internal conversion was eliminated by deuteration of NH group of macrocycle showing that high frequency NH vibrations are responsible for radiationless deactivation of electron energy of the S1 state of sensitizers. The comparison of photodynamic action chlorins and photofrin on cells level and tumors in vivo demonstrates that chlorins are more potent photosensitizers of PDT.

Losev, Anatoly P.; Nichiporovich, I. N.; Zhuravkin, Ivan N.; Zhavrid, Edvard A.

1996-12-01

388

The insecticidal neurotoxin Aps III is an atypical knottin peptide that potently blocks insect voltage-gated sodium channels  

PubMed Central

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

Bende, Niraj S.; Kang, Eunji; Herzig, Volker; Bosmans, Frank; Nicholson, Graham M.; Mobli, Mehdi; King, Glenn F.

2013-01-01

389

Identification of a ?-opioid agonist as a potent and selective lead for drug development against human African trypanosomiasis.  

PubMed

A resazurin-based cell viability assay was developed for phenotypic screening of the LOPAC 1280 'library of pharmacologically active compounds' against bloodstream forms of Trypanosoma brucei in vitro identifying 33 compounds with EC(50) values <1 ?M. Counter-screening vs. normal diploid human fibroblasts (MRC5 cells) was used to rank these hits for selectivity, with the most potent (<70 nM) and selective (>700-fold) compounds being suramin and pentamidine. These are well-known antitrypanosomal drugs which demonstrate the robustness of the resazurin cell viability assay. The most selective novel inhibitor was (+)-trans-(1R,2R)-U50,488 having an EC(50) value of 60 nM against T. brucei and 270-fold selectivity over human fibroblasts. Interestingly, (-)-U50,488, a known CNS-active ?-opioid receptor agonist and other structurally related compounds were >70-fold less active or inactive, as were several ?- and ?-opioid antagonists. Although (+)-U50,488 was well tolerated by the oral route and displayed good pharmaceutical properties, including high brain penetration, the compound was not curative in the mouse model of infection. Nonetheless, the divergence of antinociceptive and antitrypanosomal activity represents a promising start point for further exploratory chemistry. Bioinformatic studies did not reveal any obvious candidate opioid receptors and the target of this cytostatic compound is unknown. Among the other potent, but less selective screening hits were compound classes with activity against protein kinases, topoisomerases, tubulin, as well as DNA and energy metabolism. PMID:20696141

Jones, Deuan C; Hallyburton, Irene; Stojanovski, Laste; Read, Kevin D; Frearson, Julie A; Fairlamb, Alan H

2010-11-15

390

Novel analogues of istaroxime, a potent inhibitor of Na+,K+-ATPase: synthesis and structure-activity relationship.  

PubMed

We report the synthesis and biological properties of novel inhibitors of the Na(+),K(+)-ATPase as positive inotropic compounds. Following our previously described model from which Istaroxime was generated, the 5alpha,14alpha-androstane skeleton was used as a scaffold to study the space around the basic chain of our lead compound. Some compounds demonstrated higher potencies than Istaroxime on the receptor and the (E)-3-[(R)-3-pyrrolidinyl]oxime derivative, 15, was the most potent; as further confirmation of our model, the E isomers of the oxime are more potent than the Z form. The compounds tested in the guinea pig model induced positive inotropic effects, which are correlated to the in vitro inhibitory potency on the Na(+),K(+)-ATPase. The finding that all tested compounds resulted less proarrhythmogenic than digoxin, a currently clinically used positive inotropic agent, suggests that this could be a feature of the 3-aminoalkyloxime derivative class of 5alpha,14alpha-androstane. PMID:18637667

Gobbini, Mauro; Armaroli, Silvia; Banfi, Leonardo; Benicchio, Alessandra; Carzana, Giulio; Fedrizzi, Giorgio; Ferrari, Patrizia; Giacalone, Giuseppe; Giubileo, Michele; Marazzi, Giuseppe; Micheletti, Rosella; Moro, Barbara; Pozzi, Marco; Scotti, Piero Enrico; Torri, Marco; Cerri, Alberto

2008-08-14

391

Potent antitumor activities of recombinant human PDCD5 protein in combination with chemotherapy drugs in K562 cells  

SciTech Connect

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.

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

392

Molecular mechanism of viral resistance to a potent non-nucleoside inhibitor unveiled by molecular simulations.  

PubMed

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

Asthana, Shailendra; Shukla, Saumya; Ruggerone, Paolo; Vargiu, Attilio V

2014-11-11

393

Au/p-diamond ohmic contacts deposited by RF sputtering  

NASA Astrophysics Data System (ADS)

Ohmic contacts have been formed on diamond films using a monolayer Au. Au film was deposited by radio frequency sputtering. I- V measurements show the good ohmic behavior of the contacts in the as-deposited and annealed states and the specific contact resistivity obtained by circular transmission line model was 1.27 × 10 -3 and 5.43 × 10 -4 ? cm 2, respectively. Radio frequency sputtering makes an obvious interdiffusion between Au and diamond in the as-deposited contacts. Annealing the contact enhances the interdiffusion. X-ray photoelectron spectroscopy analyses and cross-sectional scan electron microscopy reveal the presence of an intermediate layer at the interface due to the intermixing between Au and diamond. Surface native oxide of the diamond film was effectively removed by treating the substrate film in boiling aqua regia solution.

Zhen, C. M.; Wang, X. Q.; Wu, X. C.; Liu, C. X.; Hou, D. L.

2008-12-01

394

A single-pixel wireless contact lens display  

NASA Astrophysics Data System (ADS)

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.

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

395

Low resistivity ohmic contacts to moderately doped n-GaAs with low temperature processing  

SciTech Connect

A low-temperature process for forming ohmic contacts to moderately doped GaAs has been optimized using a PdGe metallization scheme. Minimum specific contact resistivity of 1.5 {times} 10{sup {minus}6} {minus}cm{sup 2} has been obtained with a low anneal temperature of 250 C. Results for optimizing both time and temperature are reported and compared to GeAu n-GaAs contacts. Material compositions was analyzed by x-ray photoelectron spectroscopy and circuit metal interconnect contact resisitivity to the low-temperature processed PdGe contacts is reported. For the lowest temperature anneals considered, excess Ge on the ohmic contact layer is suspected of degrading interconnect metal contacts, while higher temperature anneals permitted interconnect metal formation with negligible contact resistivity. Atomic force microscopy measurements showed that the PdGe surface morphology is much more uniform than standard GeAu contacts.

Lovejoy, M.L.; Howard, A.J.; Zavadil, K.R.; Rieger, D.J.; Shul, R.J. [Sandia National Labs., Albuquerque, NM (United States); Barnes, P.A. [Auburn Univ., AL (United States). Dept. of Physics

1994-12-31

396

Circumbinary Components of Contact Binaries  

E-print Network

The period changes of contact binaries obtained by the analysis of eclipse minima timing are found mostly chaotic in nature. However, they are representable by a few cyclic changes superposed on a secular change. The cyclic changes are caused most probably by the third components revolving around the contact binaries. Some typical examples of the period changes of contact binaries are presented in the present contribution.

Demircan, O

2014-01-01

397

A gauge theory of nucleonic interactions by contact  

NASA Astrophysics Data System (ADS)

A gauge theory of contact is presented, based on the general idea that the local deformation of the nucleon surface at contact should be gauged by the variation of curvature. A contact force is then defined so as to cope with both the variation of curvature and the deformation. This force generalizes the classical definition of surface tension, in that it depends on the mean curvature, but also depends on the variance of the second fundamental form of surface, considered as a statistical variable over the ensemble of contact spots. It turns out that the variance of the second fundamental form does not depend but on the metric of the space of curvature parameters, organized as Riemann space. This result compels us to review the definition of physical surface of a nucleon.

Mazilu, Nicolae; Ioannou, Pavlos D.; Agop, Maricel

2014-04-01

398

Potent Delivery of Functional Proteins into Mammalian Cells in Vitro and in Vivo Using a  

E-print Network

cells have been developed including lipid-linked compounds (1), nanoparticles (2), and fu- sions cytotoxicity. We hypothesized that 36 GFP may also serve as a potent and general platform for the delivery

Liu, David R.

399

A review on cylindrospermopsin: The global occurrence, detection, toxicity and degradation of a potent cyanotoxin  

EPA Science Inventory

Abstract: Cylindrospermopsin is now recognized as a potent cyanobacterial toxin found in water bodies worldwide. The ever-increasing and global occurrence of massive and prolonged blooms of cylindrospermopsin-producing cyanobacteria in freshwater poses a potential threat to both ...

400

Lipopeptide nanoparticles for potent and selective siRNA delivery in rodents and nonhuman primates  

E-print Network

siRNA therapeutics have promise for the treatment of a wide range of genetic disorders. Motivated by lipoproteins, we report lipopeptide nanoparticles as potent and selective siRNA carriers with a wide therapeutic index. ...

Dong, Yizhou

401

METHYLATION INACTIVATES PENTAVALENT ARSENIC SPECIES BUT ACTIVATES TRIVALENT ARSENIC SPECIES TO POTENT GENOTOXICANTS  

EPA Science Inventory

Methylation Inactivates Pentavalent Arsenic Species but Activates Trivalent Arsenic Species to Potent Genotoxicants The sensitivity ofhumans to arsenic-induced cancer is thought to be related in part to the limited ability of humans to detoxify arsenic. Recently, methyl- ...

402

Assessment Forms  

NSDL National Science Digital Library

This site contains printable, downloadable forms for teachers to use in the classroom. It includes a daily point sheet, group self-evaluation, portfolio assessment chart, student progress report, student progress self-evaluation, and others.

403

Forms & Guidelines  

Cancer.gov

2003 DCP Consortia for Early Phase Prevention Trials 2003 Step 1: Developing a Cancer Prevention Clinical Trial Forms & Guidelines General Guidelines for Consortia Lead Organization to add Participating to Consortium (doc, 63kb) NCI Request for Proposals,

404

Dynamic contact angles and hydrodynamics near a moving contact line  

Microsoft Academic Search

The contact angle is an important boundary condition needed to predict the shape of menisci. However, its measurement and use under dynamic conditions are not well understood. We have measured the shape of menisci very close to moving contact lines over a suite of geometric shapes for the macroscopic menisci. The excellent agreement between theory and experiment establishes that the

John A. Marsh; S. Garoff; E. B. Dussan v

1993-01-01

405

Mitigation of epidemics in contact networks through optimal contact adaptation *  

PubMed Central

This paper presents an optimal control problem formulation to minimize the total number of infection cases during the spread of susceptible-infected-recovered SIR epidemics in contact networks. In the new approach, contact weighted are reduced among nodes and a global minimum contact level is preserved in the network. In addition, the infection cost and the cost associated with the contact reduction are linearly combined in a single objective function. Hence, the optimal control formulation addresses the tradeoff between minimization of total infection cases and minimization of contact weights reduction. Using Pontryagin theorem, the obtained solution is a unique candidate representing the dynamical weighted contact network. To find the near-optimal solution in a decentralized way, we propose two heuristics based on Bang-Bang control function and on a piecewise nonlinear control function, respectively. We perform extensive simulations to evaluate the two heuristics on different networks. Our results show that the piecewise nonlinear control function outperforms the well-known Bang-Bang control function in minimizing both the total number of infection cases and the reduction of contact weights. Finally, our results show awareness of the infection level at which the mitigation strategies are effectively applied to the contact weights. PMID:23906209

Youssef, Mina; Scoglio, Caterina

2013-01-01

406

Ferroptosis: An Iron-Dependent Form of Nonapoptotic Cell Death  

E-print Network

.03.042 SUMMARY Nonapoptotic forms of cell death may facilitate the selective elimination of some tumor cells as a potent inhibitor of ferroptosis in cancer cells and glutamate-induced cell death in organotypic rat brain results in the nonapoptotic destruction of certain cancer cells, whereas inhibition of this process may

Stockwell, Brent R.

407

Superconductor-normal-superconductor with distributed Sharvin point contacts  

DOEpatents

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.

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

1994-01-01

408

Soft electrical contacts for conductivity measurements of molecularly modified surfaces  

Microsoft Academic Search

A portable conductivity setup, using soft electrical contacts, is proposed to measure the charge transport properties of molecularly modified solid surfaces. The present technique facilitates the conductivity measurements of both single and back-to-back metal–semiconductor junctions formed on soft matter using liquid mercury columns as electrical contacts. The utility of the above setup is demonstrated for back-to-back junctions using bare and

R K Hiremath; M K Rabinal; B G Mulimani

2009-01-01

409

Soft electrical contacts for conductivity measurements of molecularly modified surfaces  

Microsoft Academic Search

A portable conductivity setup, using soft electrical contacts, is proposed to measure the charge transport properties of molecularly modified solid surfaces. The present technique facilitates the conductivity measurements of both single and back-to-back metal-semiconductor junctions formed on soft matter using liquid mercury columns as electrical contacts. The utility of the above setup is demonstrated for back-to-back junctions using bare and

R. K. Hiremath; M. K. Rabinal; B. G. Mulimani

2009-01-01

410

Contact analysis of elastic-plastic fractal surfaces  

Microsoft Academic Search

Rough surfaces are characterized by fractal geometry using a modified two-variable Weierstrass-Mandelbrot function. The developed algorithm yields three-dimensional fractal surface topographies representative of engineering rough surfaces. This surface model is incorporated into an elastic-plastic contact mechanics analysis of two approaching rough surfaces. Closed form solutions for the elastic and plastic components of the total normal force and real contact area

W. Yan; K. Komvopoulos

1998-01-01

411

Graphdiyne-metal contacts and graphdiyne transistors  

NASA Astrophysics Data System (ADS)

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

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

412

Fabrication of optically reflecting ohmic contacts for semiconductor devices  

DOEpatents

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.

Sopori, B.L.

1995-07-04

413

Aurelia aurita (Cnidaria) Oocytes' Contact Plate Structure and Development  

PubMed Central

One of the A. aurita medusa main mesoglea polypeptides, mesoglein, has been described previously. Mesoglein belongs to ZP-domain protein family and therefore we focused on A.aurita oogenesis. Antibodies against mesoglein (AB RA47) stain the plate in the place where germinal epithelium contacts oocyte on the paraffin sections. According to its position, we named the structure found the “contact plate”. Our main instrument was AB against mesoglein. ZP-domain occupies about half of the whole amino acid sequence of the mesoglein. Immunoblot after SDS-PAGE and AU-PAGE reveals two charged and high Mr bands among the female gonad germinal epithelium polypeptides. One of the gonads' polypeptides Mr corresponds to that of mesogleal cells, the other ones' Mr is higher. The morphological description of contact plate formation is the subject of the current work. Two types of AB RA47 positive granules were observed during progressive oogenesis stages. Granules form the contact plate in mature oocyte. Contact plate of A.aurita oocyte marks its animal pole and resembles Zona Pellucida by the following features: (1) it attracts spermatozoids; (2) the material of the contact plate is synthesized by oocyte and stored in granules; (3) these granules and the contact plate itself contain ZP domain protein(s); (4) contact plate is an extracellular structure made up of fiber bundles similar to those of conventional Zona Pellucida. PMID:23185235

Adonin, Leonid S.; Shaposhnikova, Tatyana G.; Podgornaya, Olga

2012-01-01

414

16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.  

Code of Federal Regulations, 2012 CFR

...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...

2012-01-01

415

16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.  

Code of Federal Regulations, 2014 CFR

...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...

2014-01-01

416

16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.  

Code of Federal Regulations, 2013 CFR

...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...

2013-01-01

417

16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.  

Code of Federal Regulations, 2011 CFR

...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...

2011-01-01

418

16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.  

Code of Federal Regulations, 2010 CFR

...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...

2010-01-01

419

Contacts in Higher Education. Guide.  

ERIC Educational Resources Information Center

This guide lists the universities and colleges in England directly funded by the Higher Education Funding Council for England, with contact information. It also includes other useful sources of information on higher education. The guide is divided into these sections: (1) higher education institutions; (2) regional contacts; (3) further education…

Higher Education Funding Council for England, Bristol.

420

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...

421

Contact modeling for robotics applications  

SciTech Connect

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.

Lafarge, R.A.; Lewis, C.

1998-08-01

422

Contact dermatitis in military personnel.  

PubMed

Military personnel encounter the same allergens and irritants as their civilian counterparts and are just as likely to develop contact dermatitis from common exposures encountered in everyday life. In addition, they face some unique exposures that can be difficult to avoid owing to their occupational duties. Contact dermatitis can be detrimental to a military member's career if he or she is unable to perform core duties or avoid the inciting substances. An uncontrolled contact dermatitis can result in the member's being placed on limited-duty (ie, nondeployable) status, needing a job or rate change, or separation from military service. We present some common causes of contact dermatitis in military personnel worldwide and some novel sources of contact dermatitis in this population that may not be intuitive. PMID:22653003

Dever, Tara T; Walters, Michelle; Jacob, Sharon

2011-01-01

423

Contact processes on the integers  

NASA Astrophysics Data System (ADS)

The three state contact process is the modification of the contact process at rate ? in which first infections occur at rate ? instead. Chapters 2 and 3 consider the three state contact process on (graphs that have as set of sites) the integers with nearest neighbours interaction (that is, edges are placed among sites at Euclidean distance one apart). Results in Chapter 2 are meant to illustrate regularity of the growth of the process under the assumption that ? geq ?, that is, reverse immunization. While in Chapter 3 two results regarding the convergence rates of the process are given. Chapter 4 is concerned with the i.i.d. behaviour of the right endpoint of contact processes on the integers with symmetric, translation invariant interaction. Finally, Chapter 5 is concerned with two monotonicity properties of the three state contact process.

Tzioufas, Achillefs

2010-10-01

424

THIS FORM SHOULD BE USED BY STAFF AND STUDENTS TO REPORT ANY INCIDENT OR NEAR MISS. PLEASE PROVIDE AS MUCH INFORMATION AS YOU CAN. IN SOME CASES THE SAFETY, HEALTH & WELLBEING DEPARTMENT MAY CONTACT YOU FOR MORE INFORMATION. THE UNIVERSITY OF EXETER ENCOU  

E-print Network

to hazardous substance Vehicle road traffic incident (off campus) Contact with heat/cold Vehicle road traffic in place e.g. separate people from an area, turned power supply off, reset alarms, contained a spillage

Bearhop, Stuart

425

Central domain of IL-33 is cleaved by mast cell proteases for potent activation of group-2 innate lymphoid cells.  

PubMed

Interleukin-33 (IL-33) is an alarmin cytokine from the IL-1 family. IL-33 activates many immune cell types expressing the interleukin 1 receptor-like 1 (IL1RL1) receptor ST2, including group-2 innate lymphoid cells (ILC2s, natural helper cells, nuocytes), the major producers of IL-5 and IL-13 during type-2 innate immune responses and allergic airway inflammation. IL-33 is likely to play a critical role in asthma because the IL33 and ST2/IL1RL1 genes have been reproducibly identified as major susceptibility loci in large-scale genome-wide association studies. A better understanding of the mechanisms regulating IL-33 activity is thus urgently needed. Here, we investigated the role of mast cells, critical effector cells in allergic disorders, known to interact with ILC2s in vivo. We found that serine proteases secreted by activated mast cells (chymase and tryptase) generate mature forms of IL-33 with potent activity on ILC2s. The major forms produced by mast cell proteases, IL-33(95-270), IL-33(107-270), and IL-33(109-270), were 30-fold more potent than full-length human IL-33(1-270) for activation of ILC2s ex vivo. They induced a strong expansion of ILC2s and eosinophils in vivo, associated with elevated concentrations of IL-5 and IL-13. Murine IL-33 is also cleaved by mast cell tryptase, and a tryptase inhibitor reduced IL-33-dependent allergic airway inflammation in vivo. Our study identifies the central cleavage/activation domain of IL-33 (amino acids 66-111) as an important functional domain of the protein and suggests that interference with IL-33 cleavage and activation by mast cell and other inflammatory proteases could be useful to reduce IL-33-mediated responses in allergic asthma and other inflammatory diseases. PMID:25313073

Lefrançais, Emma; Duval, Anais; Mirey, Emilie; Roga, Stéphane; Espinosa, Eric; Cayrol, Corinne; Girard, Jean-Philippe

2014-10-28

426

Back contact buffer layer for thin-film solar cells  

DOEpatents

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.

Compaan, Alvin D.; Plotnikov, Victor V.

2014-09-09

427

The nature of electrical interaction of Schottky contacts  

SciTech Connect

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.

Torkhov, N. A., E-mail: trkf@mail.ru [Research Institute of Semiconductor Devices (Russian Federation)

2011-08-15

428

Optofluidic realization and retaining of cell-cell contact using an abrupt tapered optical fibre  

NASA Astrophysics Data System (ADS)

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.

Xin, Hongbao; Zhang, Yao; Lei, Hongxiang; Li, Yayi; Zhang, Huixian; Li, Baojun

2013-06-01

429

Tidal Forms  

Microsoft Academic Search

We give an overview of some recent investigations on the mechanics of the processes whereby forms develop in tidal environments. The viewpoint taken here is mechanistic. Some of the questions which deserve an answer may be summarised as follows: i) do tidal channels tend to some altimetric long term equilibrium? ii) why are they typically convergent and weakly meandering? iii)

M. Bolla Pittaluga; G. Seminara; N. Tambroni

2003-01-01

430

Potent inhibition of HIV-1 by TRIM5-cyclophilin fusion proteins engineered from human components.  

PubMed

New World monkeys of the genus Aotus synthesize a fusion protein (AoT5Cyp) containing tripartite motif-containing 5 (TRIM5) and cyclophilin A (CypA) that potently blocks HIV-1 infection. We attempted to generate a human HIV-1 inhibitor modeled after AoT5Cyp, by fusing human CypA to human TRIM5 (hT5Cyp). Of 13 constructs, 3 showed substantial HIV-1-inhibitory activity when expressed in human cell lines. This activity required capsid binding by CypA and correlated with CypA linkage to the TRIM5a capsid-specificity determinant and the ability to form cytoplasmic bodies. CXCR4- and CCR5-tropic HIV-1 clones and primary isolates were inhibited from infecting multiple human macrophage and T cell lines and primary cells by hT5Cyp, as were HIV-2ROD, SIVAGMtan, FIVPET, and a circulating HIV-1 isolate previously reported to be AoT5Cyp resistant. The anti-HIV-1 activity of hT5Cyp was surprisingly more effective than that of the well-characterized rhesus TRIM5alpha, especially in T cells. hT5Cyp also blocked HIV-1 infection of primary CD4+ T cells and macrophages and conferred a survival advantage to these cells without disrupting their function. Extensive attempts to elicit HIV-1 resistance to hT5Cyp were unsuccessful. Finally, Rag2-/-gammac-/- mice were engrafted with human CD4+ T cells that had been transduced by optimized lentiviral vectors bearing hT5Cyp. Upon challenge with HIV-1, these mice showed decreased viremia and productive infection in lymphoid organs and preserved numbers of human CD4+ T cells. We conclude that hT5Cyp is an extraordinarily robust inhibitor of HIV-1 replication and a promising anti-HIV-1 gene therapy candidate. PMID:19741300

Neagu, Martha R; Ziegler, Patrick; Pertel, Thomas; Strambio-De-Castillia, Caterina; Grütter, Christian; Martinetti, Gladys; Mazzucchelli, Luca; Grütter, Markus; Manz, Markus G; Luban, Jeremy

2009-10-01

431

Engineered Single Human CD4 Domains as Potent HIV-1 Inhibitors and Components of Vaccine Immunogens ? †  

PubMed Central

Soluble forms of the HIV-1 receptor CD4 (sCD4) have been extensively characterized for more than 2 decades as promising inhibitors and components of vaccine immunogens. However, they were mostly based on the first two CD4 domains (D1D2), and numerous attempts to develop functional, high-affinity, stable soluble one-domain sCD4 (D1) have not been successful because of the strong interactions between the two domains. We have hypothesized that combining the power of structure-based design with sequential panning of large D1 mutant libraries against different HIV-1 envelope glycoproteins (Envs) and screening for soluble mutants could not only help solve the fundamental stability problem of isolated D1, but may also allow improvement of D1 affinity while preserving its cross-reactivity. By using this strategy, we identified two stable monomeric D1 mutants, mD1.1 and mD1.2, which were significantly more soluble and bound Env gp120s more strongly (50-fold) than D1D2, neutralized a panel of HIV-1 primary isolates from different clades more potently than D1D2, induced conformational changes in gp120, and sensitized HIV-1 for neutralization by CD4-induced antibodies. mD1.1 and mD1.2 exhibited much lower binding to human blood cell lines than D1D2; moreover, they preserved a ?-strand secondary structure and stability against thermally induced unfolding, trypsin digestion, and degradation by human serum. Because of their superior properties, mD1.1 and mD1.2 could be potentially useful as candidate therapeutics, components of vaccine immunogens, and research reagents for exploration of HIV-1 entry and immune responses. Our approach could be applied to other cases where soluble isolated protein domains are needed. PMID:21715496

Chen, Weizao; Feng, Yang; Gong, Rui; Zhu, Zhongyu; Wang, Yanping; Zhao, Qi; Dimitrov, Dimiter S.

2011-01-01

432

Potent cyclic enkephalin analogues for delta opioid receptors in the rat brain  

SciTech Connect

(/sup 3/H) (D-Pen/sup 2/,D-Pen/sup 5/) enkephalin ((/sup 3/H)DPDPE) and (/sup 3/H) (D-Pen/sup 2/, L-Pen/sup 5/) enkephalin ((/sup 3/H)DPLPE) characterization studies showed high affinity binding of these radioligands to rat brain membranes with dissociation constants of 1.8 and 1.0 nM, respectively, while a similar number of receptor density was found with both radiolabeled ligands (77 fmoles/mg protein). Unlabeled DPDPE inhibited both radioligands with high affinity (IC50 = 7 nM0 while morphine (IC50 = 80 nM), DAGO (IC50 = 250 nM) and PLO17 (no inhibition at 1000 nM) were less effective in inhibiting the binding, thus, illustrating the selective action of these radiolabeled ligands at the delta opioid receptor. A series of conformationally restricted D-penicillamine containing cyclic enkephalin analogues were synthesized using standard solid phase methods and their ability to inhibit (/sup 3/H)DPDPE and (/sup 3/H)DPLPE were examined in rat brain radioreceptor assays. Substitutions in the DPDPE molecule were made in phe/sup 4/. These substitutions were pNO/sub 2/-phe/sup 4/, beta-methyl-phe/sup 4/, pNO/sub 2/-beta-methyl-phe/sub 4/, pNO/sub 2/-beta-methyl-phe/sup 4/ (three isomeric forms: A,B,D). The IC50 values for the above enkephalin analogues were 3.7, 16, 7, 7, 200 nM, respectively. Thus, these potent analogues of DPDPE should be useful in determining the structure activity relationships of the delta opioid receptor in rat brain.

Lui, G.; Kao, J.; Hruby, V.; Morelli, M.; Gulya, K.; Yamamura, H.I.

1986-03-01

433

Synthetic peptides of human lysosomal cathepsin G with potent antipseudomonal activity.  

PubMed Central

Enzymatically active and inactive (diisopropylfluorophosphate-treated) cathepsin G exerted antibacterial action in vitro against Staphylococcus aureus, whereas only enzymatically active cathepsin G displayed bactericidal action against Pseudomonas aeruginosa. In order to further test the requirement for protease activity for the antipseudomonal action of cathepsin G, synthetic peptides spanning the full-length mature protein were prepared and examined for antibacterial action. Surprisingly, three structurally distinct peptides that correspond to residues 61 to 80, 117 to 136, and 198 to 223 within the full-length protein were found to exert potent antipseudomonal action (> 4.5 logs of killing at 500 micrograms/ml) against P. aeruginosa ATCC 27853 and four mucoid clinical isolates. Only the peptide (CG117-136) corresponding to residues 117 to 136 (117-RPGTLCTVAGWGRVSMRRGT-136) within cathepsin G exerted antibacterial action against the gram-positive pathogen S. aureus. The antipseudomonal action of CG117-136 was rapid and could be inhibited either by increasing concentrations of NaCl or by 0.5 mM MgCl2 plus 0.5 mM CaCl2, and these conditions appeared to reduce binding of the peptide to whole bacteria. Variants of peptide CG117-136 lacking either a hydrophobic N-terminal domain or a positively charged C-terminal domain were found to have significantly less antipseudomonal action than CG117-136. The antibacterial capacity of the all-D-enantiomeric form of peptide CG117-136 was found to be identical to that of the all-L-peptide, suggesting that the mechanism of killing does not require the recognition of a target site possessing a chiral center. Images PMID:8478079

Shafer, W M; Shepherd, M E; Boltin, B; Wells, L; Pohl, J

1993-01-01

434

Azapeptides structurally based upon inhibitory sites of cystatins as potent and selective inhibitors of cysteine proteases.  

PubMed

A series of azapeptides as potential inhibitors of cysteine proteases were synthesized. Their structures, based on the binding center of cystatins, contain an azaglycine residue (Agly) in place of the evolutionarily conserved glycine residue in the N-terminal part of the enzyme binding region of cystatins. Incorporation of Agly should lead to deactivation of the acyl-enzyme complex formed against nucleophilic attack by water molecules in the final step of peptide bond hydrolysis. The majority of synthesized azapeptides shows high inhibitory potency toward the investigated cysteine proteases, papain, cathepsin B, and cathepsin K. One of them, Z-Arg-Leu-Val-Agly-Ile-Val-OMe (compound 17), which contains in its sequence the amino acid residues from the N-terminal binding segment as well as the hydrophobic residues from the first binding loop of human cystatin C, proved to be a highly potent and selective inhibitor of cathepsin B. It inhibits cathepsin B with a K(i) value of 0.088 nM. To investigate the influence of the structure of compound 17 for its inhibitory properties, we determined its conformation by means of NMR studies and theoretical calculations. The Z-Arg-Leu-Val-Agly fragment, covalently linked to Cys29 of cathepsin B, was also developed and modeled, in the catalytic pocket of the enzyme, through a molecular dynamics approach, to analyze ligand-protein interactions in detail. Analysis of the simulation trajectories generated using the AMBER force field provided us with atomic-level understanding of the conformational variability of this inhibitor, which is discussed in the context of other experimental and theoretical data. PMID:12213061

Wieczerzak, Ewa; Drabik, Piotr; ?ankiewicz, Leszek; O?dziej, Stanis?aw; Grzonka, Zbigniew; Abrahamson, Magnus; Grubb, Anders; Brömme, Dieter

2002-09-12

435

High-level semi-synthetic production of the potent antimalarial artemisinin.  

PubMed

In 2010 there were more than 200?million cases of malaria, and at least 655,000 deaths. The World Health Organization has recommended artemisinin-based combination therapies (ACTs) for the treatment of uncomplicated malaria caused by the parasite Plasmodium falciparum. Artemisinin is a sesquiterpene endoperoxide with potent antimalarial properties, produced by the plant Artemisia annua. However, the supply of plant-derived artemisinin is unstable, resulting in shortages and price fluctuations, complicating production planning by ACT manufacturers. A stable source of affordable artemisinin is required. Here we use synthetic biology to develop strains of Saccharomyces cerevisiae (baker's yeast) for high-yielding biological production of artemisinic acid, a precursor of artemisinin. Previous attempts to produce commercially relevant concentrations of artemisinic acid were unsuccessful, allowing production of only 1.6?grams per litre of artemisinic acid. Here we demonstrate the complete biosynthetic pathway, including the discovery of a plant dehydrogenase and a second cytochrome that provide an efficient biosynthetic route to artemisinic acid, with fermentation titres of 25?grams per litre of artemisinic acid. Furthermore, we have developed a practical, efficient and scalable chemical process for the conversion of artemisinic acid to artemisinin using a chemical source of singlet oxygen, thus avoiding the need for specialized photochemical equipment. The strains and processes described here form the basis of a viable industrial process for the production of semi-synthetic artemisinin to stabilize the supply of artemisinin for derivatization into active pharmaceutical ingredients (for example, artesunate) for incorporation into ACTs. Because all intellectual property rights have been provided free of charge, this technology has the potential to increase provision of first-line antimalarial treatments to the developing world at a reduced average annual price. PMID:23575629

Paddon, C J; Westfall, P J; Pitera, D J; Benjamin, K; Fisher, K; McPhee, D; Leavell, M D; Tai, A; Main, A; Eng, D; Polichuk, D R; Teoh, K H; Reed, D W; Treynor, T; Lenihan, J; Fleck, M; Bajad, S; Dang, G; Dengrove, D; Diola, D; Dorin, G; Ellens, K W; Fickes, S; Galazzo, J; Gaucher, S P; Geistlinger, T; Henry, R; Hepp, M; Horning, T; Iqbal, T; Jiang, H; Kizer, L; Lieu, B; Melis, D; Moss, N; Regentin, R; Secrest, S; Tsuruta, H; Vazquez, R; Westblade, L F; Xu, L; Yu, M; Zhang, Y; Zhao, L; Lievense, J; Covello, P S; Keasling, J D; Reiling, K K; Renninger, N S; Newman, J D

2013-04-25

436

Bacterial contact-dependent growth inhibition (CDI)  

PubMed Central

Bacteria cooperate to form multicellular communities and compete against one another for environmental resources. Here, we review recent advances in our understanding of bacterial competition mediated by contact-dependent growth inhibition (CDI) systems. Different CDI+ bacteria deploy a variety of toxins to inhibit neighboring cells and protect themselves from autoinhibition by producing specific immunity proteins. The genes encoding CDI toxin–immunity pairs appear to be exchanged between cdi loci and are often associated with other toxin-delivery systems in diverse bacteria. CDI also appears to facilitate cooperative behavior between kin, suggesting that these systems may have other roles beyond competition. PMID:23473845

Ruhe, Zachary C.; Low, David A.; Hayes, Christopher S.

2013-01-01

437

Adapted connections on metric contact manifolds  

NASA Astrophysics Data System (ADS)

In this paper, we describe the space of adapted connections on a metric contact manifold through the space of their torsion tensors. The torsion tensor is an element of the space of TM-valued two-forms which splits into various subspaces. We study the parts of the torsion tensor according to this splitting to completely describe the space of adapted connections. We use this description to obtain characterizations of the generalized Tanaka-Webster connection and to describe adapted connections whose Dirac operators are essentially self-adjoint. Finally, Schrödinger-Lichnerowicz-type formulae are provided for these operators.

Stadtmüller, Christoph

2012-11-01

438

Bacterial contact-dependent growth inhibition.  

PubMed

Bacteria cooperate to form multicellular communities and compete against one another for environmental resources. Here, we review recent advances in the understanding of bacterial competition mediated by contact-dependent growth inhibition (CDI) systems. Different CDI+ bacteria deploy a variety of toxins to inhibit neighboring cells and protect themselves from autoinhibition by producing specific immunity proteins. The genes encoding CDI toxin-immunity protein pairs appear to be exchanged between cdi loci and are often associated with other toxin-delivery systems in diverse bacterial species. CDI also appears to facilitate cooperative behavior between kin, suggesting that these systems may have other roles beyond competition. PMID:23473845

Ruhe, Zachary C; Low, David A; Hayes, Christopher S

2013-05-01

439

Non-natural acetogenin analogues as potent Trypanosoma brucei inhibitors  

PubMed Central

A series of novel bis-tetrahydropyran 1,4-triazole analogues based on the acetogenin framework display low micromolar trypanocidal activities towards both bloodstream and insect forms of Trypanosoma brucei, the causative agent of African sleeping sickness. A divergent synthetic strategy was adopted for the synthesis of the key tetrahydropyran intermediates to enable rapid access to diastereochemical variation either side of the 1,4-triazole core. The resulting diastereomeric analogues displayed varying degrees of trypanocidal activity and selectivity in structure activity relationship studies. PMID:25145275

Florence, Gordon J.; Fraser, Andrew L.; Gould, Eoin R.; King, Elizabeth F.; Menzies, Stefanie K.; Morris, Joanne C.; Tulloch, Lindsay B.; Smith, Terry K.

2015-01-01

440

Contact mechanics of rough spheres  

NASA Astrophysics Data System (ADS)

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

Pastewka, Lars; Robbins, Mark

2013-03-01

441

Elastohydrodynamic lubrication of elliptical contacts  

NASA Technical Reports Server (NTRS)

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.

Hamrock, B. J.

1981-01-01

442

Moving Contact Lines 1 Moving Contact Lines: Scales, Regimes and  

E-print Network

, France. Key Words Wetting, spreading, wetting transitions, lubrication, contact angle, interface dynamics Abstract The speed at which liquid can move over a solid surface is strongly limited when a three

443

Stapled ??helical peptide drug development: A potent dual inhibitor of MDM2 and MDMX for p53-dependent cancer therapy  

PubMed Central

Stapled ??helical peptides have emerged as a promising new modality for a wide range of therapeutic targets. Here, we report a potent and selective dual inhibitor of MDM2 and MDMX, ATSP-7041, which effectively activates the p53 pathway in tumors in vitro and in vivo. Specifically, ATSP-7041 binds both MDM2 and MDMX with nanomolar affinities, shows submicromolar cellular activities in cancer cell lines in the presence of serum, and demonstrates highly specific, on-target mechanism of action. A high resolution (1.7-Å) X-ray crystal structure reveals its molecular interactions with the target protein MDMX, including multiple contacts with key amino acids as well as a role for the hydrocarbon staple itself in target engagement. Most importantly, ATSP-7041 demonstrates robust p53-dependent tumor growth suppression in MDM2/MDMX-overexpressing xenograft cancer models, with a high correlation to on-target pharmacodynamic activity, and possesses favorable pharmacokinetic and tissue distribution properties. Overall, ATSP-7041 demonstrates in vitro and in vivo proof-of-concept that stapled peptides can be developed as therapeutically relevant inhibitors of protein–protein interaction and may offer a viable modality for cancer therapy. PMID:23946421

Chang, Yong S.; Graves, Bradford; Guerlavais, Vincent; Tovar, Christian; Packman, Kathryn; To, Kwong-Him; Olson, Karen A.; Kesavan, Kamala; Gangurde, Pranoti; Mukherjee, Aditi; Baker, Theresa; Darlak, Krzysztof; Elkin, Carl; Filipovic, Zoran; Qureshi, Farooq Z.; Cai, Hongliang; Berry, Pamela; Feyfant, Eric; Shi, Xiangguo E.; Horstick, James; Annis, D. Allen; Manning, Anthony M.; Fotouhi, Nader; Nash, Huw; Vassilev, Lyubomir T.; Sawyer, Tomi K.

2013-01-01

444

Epitope Mapping of M36, a Human Antibody Domain with Potent and Broad HIV-1 Inhibitory Activity  

PubMed Central

M36 is the first member of a novel class of potent HIV-1 entry inhibitors based on human engineered antibody domains (eAds). It exhibits broad inhibitory activity suggesting that its CD4-induced epitope is highly conserved. Here, we describe fine mapping of its epitope by using several approaches. First, a panel of mimotopes was affinity-selected from a random peptide library and potential m36-binding residues were computationally predicted. Second, homology modeling of m36 and molecular docking of m36 onto gp120 revealed potentially important residues in gp120-m36 interactions. Third, the predicted contact residues were verified by site-directed mutagenesis. Taken together, m36 epitope comprising three discontinuous sites including six key gp120 residues (Site C1: Thr123 and Pro124; Site C3: Glu370 and Ile371; Site C4: Met426 and Trp427) were identified. In the 3D structure of gp120, the sites C1 and C4 are located in the bridging sheet and the site C3 is within the ?15-?3 excursion, which play essential roles for the receptor- and coreceptor-binding and are major targets of neutralizing antibodies. Based on these results we propose a precise localization of the m36 epitope and suggest a mechanism of its broad inhibitory activity which could help in the development of novel HIV-1 therapeutics based on eAds. PMID:23776690

Chen, Weizao; Yuan, Xiaohui; Chong, Huihui; Prabakaran, Ponraj; Dimitrov, Dimiter S.; He, Yuxian

2013-01-01

445

Epitope mapping of M36, a human antibody domain with potent and broad HIV-1 inhibitory activity.  

PubMed

M36 is the first member of a novel class of potent HIV-1 entry inhibitors based on human engineered antibody domains (eAds). It exhibits broad inhibitory activity suggesting that its CD4-induced epitope is highly conserved. Here, we describe fine mapping of its epitope by using several approaches. First, a panel of mimotopes was affinity-selected from a random peptide library and potential m36-binding residues were computationally predicted. Second, homology modeling of m36 and molecular docking of m36 onto gp120 revealed potentially important residues in gp120-m36 interactions. Third, the predicted contact residues were verified by site-directed mutagenesis. Taken together, m36 epitope comprising three discontinuous sites including six key gp120 residues (Site C1: Thr123 and Pro124; Site C3: Glu370 and Ile371; Site C4: Met426 and Trp427) were identified. In the 3D structure of gp120, the sites C1 and C4 are located in the bridging sheet and the site C3 is within the ?15-?3 excursion, which play essential roles for the receptor- and coreceptor-binding and are major targets of neutralizing antibodies. Based on these results we propose a precise localization of the m36 epitope and suggest a mechanism of its broad inhibitory activity which could help in the development of novel HIV-1 therapeutics based on eAds. PMID:23776690

Wan, Chao; Sun, Jianping; Chen, Weizao; Yuan, Xiaohui; Chong, Huihui; Prabakaran, Ponraj; Dimitrov, Dimiter S; He, Yuxian

2013-01-01

446

Heavy metal ions are potent inhibitors of protein folding  

SciTech Connect

Environmental and occupational exposure to heavy metals such as cadmium, mercury and lead results in severe health hazards including prenatal and developmental defects. The deleterious effects of heavy metal ions have hitherto been attributed to their interactions with specific, particularly susceptible native proteins. Here, we report an as yet undescribed mode of heavy metal toxicity. Cd{sup 2+}, Hg{sup 2+} and Pb{sup 2+} proved to inhibit very efficiently the spontaneous refolding of chemically denatured proteins by forming high-affinity multidentate complexes with thiol and other functional groups (IC{sub 50} in the nanomolar range). With similar efficacy, the heavy metal ions inhibited the chaperone-assisted refolding of chemically denatured and heat-denatured proteins. Thus, the toxic effects of heavy metal ions may result as well from their interaction with the more readily accessible functional groups of proteins in nascent and other non-native form. The toxic scope of heavy metals seems to be substantially larger than assumed so far.

Sharma, Sandeep K. [Biochemisches Institut, Universitaet Zuerich, CH-8057 Zuerich (Switzerland); Departement de Biologie Moleculaire Vegetale, Universite de Lausanne, CH-1015 Lausanne (Switzerland); Goloubinoff, Pierre [Departement de Biologie Moleculaire Vegetale, Universite de Lausanne, CH-1015 Lausanne (Switzerland); Christen, Philipp [Biochemisches Institut, Universitaet Zuerich, CH-8057 Zuerich (Switzerland)], E-mail: christen@bioc.uzh.ch

2008-07-25

447

Antimicrobial 14-helical beta-peptides: potent bilayer disrupting agents.  

PubMed

The interactions of two amphiphilic and cationic, nine-residue beta-peptides with liposomal membranes were studied. These beta-peptides are shown to form 14-helices in the presence of bilayers. Membrane binding and membrane permeabilization occur preferentially in the presence of anionic lipids. The beta-peptides have the ability to cause tranbilayer diffusion of phospholipids, form pores, and promote lipid mixing between liposomes. These beta-peptides have previously been shown to display antimicrobial activity comparable to that of a longer beta-peptide, beta-17, which adopts a different type of helical conformation (12-helix), and to the 23 amino acid (Ala(8,13,18))-magainin-II-amide, which adopts an alpha-helical conformation. In addition, these 14-helical beta-peptides show relatively low hemolytic activity. The biological potency and microbial specificity of the 14-helical beta-peptides, despite their relatively short length, suggests that 14-helices can be particularly disruptive to microbial membranes. PMID:15260496

Epand, Raquel F; Raguse, Tami L; Gellman, Samuel H; Epand, Richard M

2004-07-27

448

Mutant Tristetraprolin: a Potent Inhibitor of Malignant Glioma Cell Growth  

PubMed Central

Malignant gliomas rely on the production of certain critical growth factors including VEGF, interleukin (IL)-6 and IL-8, to fuel rapid tumor growth, angiogenesis, and treatment resistance. Post-transcriptional regulation through adenine and uridine-rich elements (ARE) of the 3? untranslated region (UTR) is one mechanism for upregulating these and other growth factors. In glioma cells, we have shown that the post-transcriptional machinery is optimized for growth factor upregulation secondary to overexpression of the mRNA stabilizer, HuR. The negative regulator, tristetraprolin (TTP), on the other hand, may be suppressed because of extensive phosphorylation. Here we test that possibility by analyzing the phenotypic effects of a mutated form of TTP (mt-TTP) in which 8 phosphoserine residues were converted to alanines. We observed a significantly enhanced negative effect on growth factor expression in glioma cells at the post-transcriptional and transcriptional levels. The protein became stabilized and displayed significantly increased antiproliferative effects compared to wild-type TTP. Macroautophagy was induced with both forms of TTP, but inhibition of autophagy did not affect cell viability. We conclude that glioma cells suppress TTP function through phosphorylation of critical serine residues which in turn contributes to growth factor upregulation and tumor progression. PMID:23525947

Suswam, Esther A.; Shacka, John J.; Walker, Kiera; Lu, Liang; Li, Xuelin; Si, Ying; Zhang, Xiaowen; Zheng, Lei; Nabors, L. Burt; Cao, Heping; King, Peter H.

2013-01-01

449

Method and apparatus for high-efficiency direct contact condensation  

DOEpatents

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.

Bharathan, Desikan (Lakewood, CO); Parent, Yves (Golden, CO); Hassani, A. Vahab (Golden, CO)

1999-01-01

450

Method and apparatus for high-efficiency direct contact condensation  

DOEpatents

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.

Bharathan, D.; Parent, Y.; Hassani, A.V.

1999-07-20

451

Schottky contacts to In2O3  

NASA Astrophysics Data System (ADS)

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.

von Wenckstern, H.; Splith, D.; Schmidt, F.; Grundmann, M.; Bierwagen, O.; Speck, J. S.

2014-04-01

452

Thermal contact conductance of spherical, rough metals  

SciTech Connect

Junction thermal conductance is an important consideration in such applications as thermally induced stresses in supersonic and hypersonic flight vehicles, nuclear reactor cooling, electronics packaging, spacecraft thermal control, gas turbine and internal combustion engine cooling, and cryogenic liquid storage. A fundamental problem in analyzing and predicting junction thermal conductance is thermal contact conductance of non-flat, rough metals. Workable models have been previously derived for the limiting idealized cases of flat, rough and spherical, smooth surfaces. However, until now, no tractable models have been advanced for non-flat, rough surfaces (so called engineering surfaces) which are much more commonly dealt with in practice. The present investigation details the synthesis of previously derived models for macroscopically non-uniform thermal contact conductance and contact of non-flat, rough spheres, into a thermo-mechanical model, its refinement, and its presentation in an easily applied format. The present model is compared to representative experimental conductance results form the literature for stainless steel 304 with widely varying flatness deviation and roughness. Also included in the comparisons is a previous, often cited model for flat, rough metals to which the present model reduces in the limit of flat surfaces. The present model agrees well with the experimental results over the wide ranges of flatness deviation and roughness for which data was available. Conversely, the previous, well known model becomes increasingly overpredictive with increasing flatness deviation.

Lambert, M.A. [San Jose State Univ., CA (United States). Dept. of Mechanical Engineering; Fletcher, L.S. [Texas A and M Univ., College Station, TX (United States). Dept. of Mechanical Engineering

1996-12-31

453

Allergic contact dermatitis from ketoconazole.  

PubMed

Ketoconazole is a widely used imidazole antifungal agent. True contact allergy to topical ketoconazole is rare, and few cases of patients with contact allergy to ketoconazole have been reported. We present the case of a patient with a history of undiagnosed recurrent dermatitis who developed acute facial swelling and pruritus after using ketoconazole cream and shampoo for the treatment of seborrheic dermatitis. Patch testing revealed true contact allergy to ketoconazole without cross-reactivity to 4 other imidazole antifungals. Review of the patient's medical record suggested that prior incidences of dermatitis might have been due to ketoconazole exposure. When the patient avoided this imidazole agent, the dermatitis resolved. PMID:25279470

Liu, Jing; Warshaw, Erin M

2014-09-01

454

Airborne contact dermatitis to drugs.  

PubMed

Contact dermatitis is defined as "airborne" when the causative factor is present in the environment and may determine irritative or allergic skin reactions. It is often work-related. In this review of the literature, we focus our attention on airborne contact dermatitis due to pharmaceutical compounds. Contact reactions to medications, often occupation-related, occur mainly in two exposed groups: employees of pharmaceutical industries involved in the production of the drugs and healthcare workers who use the drugs for therapeutic aims. PMID:22445186

Minciullo, P L; Imbesi, S; Tigano, V; Gangemi, S

2013-01-01

455

[Contact lenses--an overview].  

PubMed

Contact lenses are a modern possibility to correct defective sights as an alternative to glasses. They are not only used because of cosmetic reasons but also if there is optical or therapeutical indication from the medical point of view. For keratoconus and cornea globosa are hard contact lenses not only the unique efficient possibility for correction but also contemporary therapy. If cornea is irregular-for instance when there are cicatrices-an essential improvement can be achieved with hard contact lenses in comparison to glasses. PMID:9340926

Azem, H

1997-01-01

456

Wraparound-contact solar cells  

NASA Technical Reports Server (NTRS)

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.

Baraona, C. R.; Klucher, T. M.; Thornhill, J. W.; Scott-Monck, J.

1979-01-01

457

UC Davis MIND Institute Donor Payment Form  

E-print Network

UC Davis MIND Institute Donor Payment Form Contact Information: Name the need is greatest within MIND Institute (ND40567) ADHD (ADHDMND) Autism (AUTISM1) Chromosome 22q11: ____________________________ (Please Specify) Send the completed form to: c/o UC Davis MIND Institute Health Science Advancement 4900

Leistikow, Bruce N.

458

Contact Pressure and Shear Stress Analysis on Conforming Contact Problem  

NASA Astrophysics Data System (ADS)

Two methods to solve a conforming contact problem are proposed. First method is general and can be applicable to the contact case between elastic arbitrary shape bodies. For verification FEA is performed on the convex-concave sphere contact, and the result of this method is well corresponding to the FEA result. However, the accuracy deteriorates when the mesh aspect ratio is extremely large. This phenomenon is caused by the usage of numerical integration for the calculation of influence coefficient. The second method is devised to avoid this problem, while this improved method is applicable only to the case when the contact area can be considered to be on a cylinder surface. By using this method, the contact pressure can be obtained without the deterioration even in the case of edge load occurring between ball bearing race shoulder and ball. The results of the contact pressure and the shear stress that is necessary for bearing life estimation are compared with the FEA result, which showed well correspondence.

Nagatani, Haruo; Imou, Akitoshi

459

Thienorphine is a potent long-acting partial opioid agonist: a comparative study with buprenorphine.  

PubMed

A strategy in the development of new treatment for opioid addiction is to find partial opioid agonists with properties of long duration of action and high oral bioavailability. In a search for such compounds, thienorphine, a novel analog of buprenorphine, was synthesized. Here, we reported that, like buprenorphine, thienorphine bound potently and nonselectively to mu-, delta-, and kappa-opioid receptors stably expressed in CHO (Chinese hamster ovary) cells and behaved as a partial agonist at mu-opioid receptor. However, some differences were observed between the pharmacological profiles of thienorphine and buprenorphine. In vitro, thienorphine was more potent than buprenorphine in inhibiting [3H]diprenorphine and stimulating guanosine 5'-O-(3-[35S]thio)triphosphate binding to rat mu-opioid receptor stably expressed in CHO cells. In vivo, thienorphine exhibited a less potent but more efficacious antinociceptive effect with an ED50 value of 0.25 mg/kg s.c. and more potent antimorphine effect with an ED50 value of 0.64 mg/kg intragastric, compared with buprenorphine. Additionally, the bioavailability of thienorphine was greatly higher than that of buprenorphine after oral administration. Moreover, compared with buprenorphine, thienorphine showed a similar long-lasting antinociceptive effect but a much longer antagonism of morphine-induced lethality (more than 15 days). These results indicate that thienorphine is a potent, long-acting partial opioid agonist with high oral bioavailability and may have possible application in treating addiction. PMID:16569757

Yu, Gang; Yue, Yong-Juan; Cui, Meng-Xun; Gong, Ze-Hui

2006-07-01

460

First principles study of metal contacts to monolayer black phosphorous  

NASA Astrophysics Data System (ADS)

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.

Chanana, Anuja; Mahapatra, Santanu

2014-11-01

461

Soft toric contact lens prescribing in different countries.  

PubMed

There have been significant improvements in toric soft contact lens design over the past decade. Data from our international contact lens prescribing survey were mined to assess recent trends in toric soft contact lens fitting. This survey was conducted by sending up to 1000 survey forms to contact lens fitters in Australia, Canada, Japan, the Netherlands, Norway, the UK and the USA each year between 2000 and 2009. Practitioners were asked to record data relating to the first 10 contact lens fits or refits performed after receiving the forms and to return them to us for analysis. The data revealed a gradual increase in the extent of toric soft lens fitting this century. Excluding Japan--which had a consistently low rate of soft toric lens fitting over the survey period--soft toric lenses now represent over 35% of all soft lenses prescribed; it can be assumed that, on average (and again excluding Japan), all cases of astigmatism 0.75 D or less remains uncorrected among contact lens wearers. Toric lenses are fitted more to those who are older, full-time wearers and reusable lens wearers, and less to those wearing silicone hydrogel and extended wear lenses. PMID:20869903

Efron, Nathan; Morgan, Philip B; Helland, Magne; Itoi, Motozumi; Jones, Deborah; Nichols, Jason J; van der Worp, Eef; Woods, Craig A

2011-02-01

462

Using Tutte polynomials to characterize sexual contact networks  

NASA Astrophysics Data System (ADS)

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.

Cadavid Muñoz, Juan José

2014-06-01

463

Non-natural acetogenin analogues as potent Trypanosoma brucei inhibitors.  

PubMed

Neglected tropical diseases remain a serious global health concern. Here, a series of novel bis-tetrahydropyran 1,4-triazole analogues based on the framework of chamuvarinin, a polyketide natural product isolated from the annonaceae plant species are detailed. The analogues synthesized display low micromolar trypanocidal activities towards both bloodstream and insect forms of Trypanosoma brucei, the causative agent of African sleeping sickness, also known as Human African Trypanosomiasis (HAT). A divergent synthetic strategy was adopted for the synthesis of the key tetrahydropyran intermediates to enable rapid access to diastereochemical variation either side of the 1,4-triazole core. The resulting diastereomeric analogues displayed varying degrees of trypanocidal activity and selectivity in structure-activity relationship studies. Together, the biological potency and calculated lipophilicity values indicate that while there is room for improvement, these derivatives may represent a promising novel class of anti-HAT agents. PMID:25145275

Florence, Gordon J; Fraser, Andrew L; Gould, Eoin R; King, Elizabeth F B; Menzies, Stefanie K; Morris, Joanne C; Tulloch, Lindsay B; Smith, Terry K

2014-11-01

464

Localized ohmic contact through a passivation dielectric for solar cell rear surface design  

NASA Astrophysics Data System (ADS)

We report the demonstration of a method for forming localized ohmic contact through dielectric passivation layers, via a laser doped region, with no etching prior to metal deposition. A simple bench top voltage source contacted to the gate and bulk of a test Metal-Insulator-Semiconductor device facilitates localized heating leading to ohmic contact formation. The surface passivation qualities of the dielectrics are preserved away from the contact region using this method, as hard dielectric breakdown is restricted to the laser doped region. This is a potential technique for precisely contacting rear surface of high efficiency solar cells.

Western, Ned J.; Sung, Andrew; Wenham, Stuart R.; Bremner, Stephen P.

2013-06-01

465

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

466

Enhancing the imagined contact effect.  

PubMed

Recent research has found that mentally simulating positive out-group contact experiences can promote tolerance and more positive intergroup perceptions. We investigated two ways of enhancing this imagined contact effect. In Study 1 we found that asking participants to generate more detail in their imagined encounter led to expectations of their having a greater number of out-group acquaintances in the future. In Study 2 we found that instructing participants to close their eyes during an imagined encounter led to heightened intentions to engage in future actual contact. These findings add further support to the notion that imagining intergroup contact may be a valuable addition to existing interventions aimed at improving intergroup relations. PMID:21375129

Husnu, Senel; Crisp, Richard John

2011-01-01

467

[Contact lens-related keratitis].  

PubMed

Nowadays, keratitis, corneal infection due to wearing contact lens means an increasingly serious problem. Neglected cases may lead to corneal damage that can cause blindness in cases of otherwise healthy eyes. Early diagnosis based on the clinical picture and the typical patient history is an important way of prevention. Prophylaxis is substantial to avoid bacterial and viral infection that is highly essential in this group of diseases. Teaching contact lens wearers the proper contact lens care, storage, sterility, and hygiene regulations is of great importance. In case of corneal inflammation early accurate diagnosis supported by microbiological culture from contact lenses, storage boxes or cornea is very useful. Thereafter, targeted drug therapy or in therapy-resistant cases surgical treatment may even be necessary in order to sustain suitable visual acuity. PMID:24184930

Steiber, Zita; Berta, András; Módis, László

2013-11-10

468

Elastohydrodynamic lubrication of rectangular contacts  

NASA Technical Reports Server (NTRS)

An isothermal elastohydrodynamically lubricated rectangular contact was evaluated numerically. This required the simultaneous solution of the elasticity and Reynolds equations. In the elasticity analysis the contact zone was divided into equal rectangular areas, and it was assumed that a uniform pressure was applied over each area. The elastohydrodynamic lubrication theory thus developed was used to investigate the influence of the dimensionless speed, load, and materials parameters on minimum film thickness. Ten cases were used in obtaining the minimum film thickness formula. Plots are shown that indicate the details of the pressure distribution, film shape, and flow. The characteristic pressure spike is clearly in evidence as is the parallel film shape through the central portion of the contact, with a minimum film thickness occurring near the outlet of the contact.

Hamrock, B. J.; Jacobson, B. O.

1983-01-01

469

Elastohydrodynamic lubrication of line contacts  

NASA Technical Reports Server (NTRS)

An isothermal elastohydrodynamically lubricated rectangular contact was evaluated numerically. This required the simultaneous solution of the elasticity and Reynolds equations. In the elasticity analysis the contact zone was divided into equal rectangular areas, and it was assumed that a uniform pressure was applied over each area. The elastohydrodynamic lubrication theory thus developed was used to investigate the influence of the dimensionless speed, load, and materials parameters on minimum film thickness. Ten cases were used in obtaining the minimum film thickness formula. Plots are shown that indicate the details of the pressure distribution, film shape, and flow. The characteristic pressure spike is clearly in evidence as is the parallel film shape through the central portion of the contact, with a minimum film thickness occurring near the outlet of the contact.

Hamrock, B. J.; Jacobson, B. O.

1984-01-01

470

Contact Us: MedlinePlus  

MedlinePLUS

... Videos & Cool Tools ESPAÑOL Contact the U.S. National Library of Medicine Thank you for visiting MedlinePlus. We ... your inquiry. For further information see the National Library of Medicine's Customer Service Policy . Please note that ...

471

Model of contact transitioning with \\  

Microsoft Academic Search

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 \\

John P. Barber; Yuri A. Dreizin

1995-01-01

472

Structure-guided discovery of 1,3,5 tri-substituted benzenes as potent and selective matriptase inhibitors exhibiting in vivo antitumor efficacy.  

PubMed

Matriptase is a serine protease implicated in cancer invasion and metastasis. Expression of matriptase is frequently dysregulated in human cancers and matriptase has been reported to activate latent growth factors such as hepatocyte growth factor/scatter factor, and proteases such as urokinase plasminogen activator suggesting that matriptase inhibitors could have therapeutic potential in treatment of cancer. Here we report a structure-based approach which led to the discovery of selective and potent matriptase inhibitors with benzene as central core having 1,3,5 tri-substitution pattern. X-ray crystallography of one of the potent analogs in complex with matriptase revealed strong hydrogen bonding and salt-bridge interactions in the S1 pocket, as well as strong CH-? contacts between the P2/P4 cyclohexyl and Trp215 side-chain. An additional interaction of the pendant amine at cyclohexyl with Gln175 side-chain results in substantial improvement in matriptase inhibition and selectivity against other related serine proteases. Compounds 15 and 26 showed tumor growth inhibition in a subcutaneous DU-145 prostate cancer mouse model. These compounds could be useful as tools to further explore the biology of matriptase as a drug target. PMID:24794746

Goswami, Rajeev; Mukherjee, Subhendu; Ghadiyaram, Chakshusmathi; Wohlfahrt, Gerd; Sistla, Ramesh K; Nagaraj, Jwala; Satyam, Leena K; Subbarao, Krishnaprasad; Palakurthy, Rajendra K; Gopinath, Sreevalsam; Krishnamurthy, Narasimha R; Ikonen, Tarja; Moilanen, Anu; Subramanya, Hosahalli S; Kallio, Pekka; Ramachandra, Murali

2014-06-15

473

Social contact synchronizes free-running activity rhythms of diurnal palm squirrels.  

PubMed

Social contact with conspecifics entrains rhythms of a number of species, although convincing demonstrations of the phenomenon in diurnal mammals are limited. The present study examined the question of whether social contact mutually synchronizes free-running locomotor activity rhythms of the diurnal Indian palm squirrel, Funambulus pennanti. Twelve male squirrels were housed individually, without visual contact, in two separate laboratories (six in each laboratory). The squirrels were initially held under opposing light-dark (LD) schedules (with an 11 h phase difference), and were then placed under constant bright light (LL). Squirrels from separate laboratories were paired together, and each pair was placed into a fresh cage on the day of the pairing. After 48 days of social contact, the squirrel pairs were separated, and returned to their original positions in the two laboratories in fresh cages. Free-running phase and period were assessed prior to and after the social contact for each squirrel. The phase difference in the free-running rhythms of pairs of squirrels was significantly decreased following social contact. Actogram records revealed strong evidence of social synchronization of free-running rhythms in four of the six pairs. For the remaining two pairs, the data were ambiguous. This study confirmed the findings in other species, that social cues are a potent zeitgeber for F. pennanti. PMID:10222468

Rajaratnam, S M; Redman, J R