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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

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

3

Direct Contact Detonation Explosives Metal Forming.  

National Technical Information Service (NTIS)

The forming of hemispheres from flat circular metal blanks by the use of compression forming dies and nitroguanidine detonated in direct contact with the workpiece is described. Direct contact detonation effects are discussed. Relationships between workpi...

J. Savitt, R. E. Conover

1965-01-01

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

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

6

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

7

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

8

Thin film process forms effective electrical contacts on semiconductor crystals  

NASA Technical Reports Server (NTRS)

Process makes microscopic, low-resistance electrical contacts on hexagonal n-type silicon carbide crystals used for microelectronic devices. A vacuum deposition of aluminum is etched to expose the bare silicon carbide where the electrical contacts are made. Sputtering alternating layers of tantalum and gold forms the alloy film.

Formigoni, N. P.; Roberts, J. S.

1967-01-01

9

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

10

Autophagosomes form at ER-mitochondria contact sites.  

PubMed

Autophagy is a tightly regulated intracellular bulk degradation/recycling system that has fundamental roles in cellular homeostasis. Autophagy is initiated by isolation membranes, which form and elongate as they engulf portions of the cytoplasm and organelles. Eventually isolation membranes close to form double membrane-bound autophagosomes and fuse with lysosomes to degrade their contents. The physiological role of autophagy has been determined since its discovery, but the origin of autophagosomal membranes has remained unclear. At present, there is much controversy about the organelle from which the membranes originate--the endoplasmic reticulum (ER), mitochondria and plasma membrane. Here we show that autophagosomes form at the ER-mitochondria contact site in mammalian cells. Imaging data reveal that the pre-autophagosome/autophagosome marker ATG14 (also known as ATG14L) relocalizes to the ER-mitochondria contact site after starvation, and the autophagosome-formation marker ATG5 also localizes at the site until formation is complete. Subcellular fractionation showed that ATG14 co-fractionates in the mitochondria-associated ER membrane fraction under starvation conditions. Disruption of the ER-mitochondria contact site prevents the formation of ATG14 puncta. The ER-resident SNARE protein syntaxin 17 (STX17) binds ATG14 and recruits it to the ER-mitochondria contact site. These results provide new insight into organelle biogenesis by demonstrating that the ER-mitochondria contact site is important in autophagosome formation. PMID:23455425

Hamasaki, Maho; Furuta, Nobumichi; Matsuda, Atsushi; Nezu, Akiko; Yamamoto, Akitsugu; Fujita, Naonobu; Oomori, Hiroko; Noda, Takeshi; Haraguchi, Tokuko; Hiraoka, Yasushi; Amano, Atsuo; Yoshimori, Tamotsu

2013-03-21

11

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

E-print Network

Contact resistance in organic transistors that use source and drain electrodes formed by soft stamps against organic semiconductor films can yield high-performance organic transistors. This article, respectively. The analysis uses models developed for characterizing amorphous silicon transistors. The results

Rogers, John A.

12

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

Federal Register 2010, 2011, 2012, 2013

...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

13

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

Federal Register 2010, 2011, 2012, 2013

...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

14

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

Federal Register 2010, 2011, 2012, 2013

...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

15

Sulphur-containing derivatives structurally related to fenoxycarb are potent growth inhibitors against the intracellular form of Trypanosoma cruzi.  

PubMed

Sulphur-containing derivatives structurally related to the insect growth regulator fenoxycarb were shown to be extremely active antiproliferative agents against the amastigote form of Trypanosoma cruzi in in vitro assays. All of these drugs had previously been proved to be remarkably potent growth inhibitors against the epimastigote form of the parasite. PMID:10724027

Rodriguez, J B; Docampo, R; Gros, E G

2000-01-01

16

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

17

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

18

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

NASA Astrophysics Data System (ADS)

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

Zhuang, Shoubing

2013-05-01

19

Preplacement Screening Patient Contact Form UF Employee/Volunteer  

E-print Network

abuse/alcoholism Drug abuse/addiction Immunosuppression Latex allergy or other skin sensitivities of the information you have given above? Yes No If yes, daytime phone ( ) How may we contact you if we need more information? E-mail address: Phone #: Mailing Address: Other #s: Signature: Date: #12;Preplacement Screening

Slatton, Clint

20

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

21

Effective 10/2013 Questions about this form? Contact HR Staffing &  

E-print Network

Effective 10/2013 Questions about this form? Contact HR Staffing & Recruitment E-mail: employment about this form? Contact HR Staffing & Recruitment E-mail: employment@uchicago.edu Page 2 of 10 Contents And Remember... When asking any type of question, your--and the applicant's--best guide is a thorough job

He, Chuan

22

Effective 10/2013 Questions about this form? Contact HR Staffing & Recruitment  

E-print Network

Effective 10/2013 Questions about this form? Contact HR Staffing & Recruitment E-mail: employment about this form? Contact HR Staffing & Recruitment E-mail: employment@uchicago.edu Page 2 of 20 Contents... When asking any type of question, your--and the applicant's--best guide is a thorough job description

He, Chuan

23

EMERGENCY CONTACT AND MEDICAL INFORMATION FORM PLEASE MAIL OR FAX BEFORE MARCH 31, 2014  

E-print Network

EMERGENCY CONTACT AND MEDICAL INFORMATION FORM PLEASE MAIL OR FAX BEFORE MARCH 31, 2014 As stated officer, employee or agent of IIT to secure any and all necessary emergency medical treatment for me by any of the foregoing parties seeking to secure me medical assistance: EMERGENCY CONTACT INFORMATION

Heller, Barbara

24

EMERGENCY CONTACT AND MEDICAL INFORMATION FORM PLEASE MAIL OR FAX BEFORE MARCH 29, 2013  

E-print Network

EMERGENCY CONTACT AND MEDICAL INFORMATION FORM PLEASE MAIL OR FAX BEFORE MARCH 29, 2013 As stated officer, employee or agent of IIT to secure any and all necessary emergency medical treatment for me by any of the foregoing parties seeking to secure me medical assistance: EMERGENCY CONTACT INFORMATION

Saniie, Jafar

25

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

Cancer.gov

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

26

EMPLOYEE CONTACT & DEPOSIT INFORMATION FORM Forward to your Human Resources Services Area Office  

E-print Network

EMPLOYEE CONTACT & DEPOSIT INFORMATION FORM Forward to your Human Resources Services Area Office (1 INFORMATION FORM Forward to your Human Resources Services Area Office (2) HR/EE/REV1.7/2007/12/04 F DEPOSIT to the University Secretary, Gilmour Hall, Room 210 McMaster University. FOR HR USE ONLY Position Code Recruitment

Haykin, Simon

27

Effective 10/2013 Questions about this form? Contact HR Staffing & Recruitment  

E-print Network

Question N Y Details Underutilized? Recruiting N Y Details Search plan developed? External job posting? Did CHECKLIST FOR RECRUITMENT & SELECTION Who conducted the phone screens? Were the phone screen questions jobEffective 10/2013 Questions about this form? Contact HR Staffing & Recruitment E-mail: employment

He, Chuan

28

A New Form of Rolling Contact Damage in Grease-Lubricated, Deep-Groove Ball Bearings  

Microsoft Academic Search

A new form of rolling contact damage was discovered in the fatigue tests of series 6206 deep groove ball bearings under pure radial load with grease lubrication. The appearance of the damage reveals a few cracks at right angles to the rolling direction of the ball, along with the formation of a dent about 20 ? m deep in the

Takeo Yoshioka; Shigeo Simizu; Hirokazu Shimoda

2009-01-01

29

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

E-print Network

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

Chu, Xi

30

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

DOEpatents

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

Hogan, S.J.

1983-03-13

31

Effective 10/2013 Questions about this form? Contact HR Employee Relations  

E-print Network

a voluntary resignation in writing especially when the resignation is received verbally. Terminate email information, cell phone, lap top, etc. Forward termination and resignation letters and Notices of TerminationEffective 10/2013 Questions about this form? Contact HR ­ Employee Relations SEPARATION CHECKLIST

Scherer, Norbert F.

32

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.

33

Optimization of contact forces in tailor-welded blanks forming process  

Microsoft Academic Search

To attain the objective of minimizing the harmful movement of the weld joint in tailor-welded blanks (TWBs) forming, a novel\\u000a optimization methodology based on dynamic explicit finite element simulation is presented to determine optimum contact forces.\\u000a In this methodology, forming limit diagram (FLD) models developed for different types of TWBs are treated as a criterion of\\u000a constraint in optimizations. Due

Jun Zhang

2007-01-01

34

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

35

Thin Film Solid-State Reactions Forming Carbides as Contact Materials for Carbon-Containing Semiconductors  

SciTech Connect

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 100 to 1100 C). W first forms W{sub 2}C and then WC; Mo forms Mo{sub 2}C; Fe forms Fe{sub 3}C; Cr first forms metastable phases Cr{sub 2}C and Cr{sub 3}C{sub 2-x}, and finally forms Cr{sub 3}C{sub 2}; V forms VC{sub x}; Nb transforms into Nb{sub 2}C followed by NbC; Ti forms TiC; Ta first forms Ta{sub 2}C 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.; Detavernier, C.; Van Meirhaeghe, R.; Lavoie, C.

2007-01-01

36

ALUMNI CAREER NETWORK REQUEST FORM The Alumni Career Network program is designed to provide career contacts to students  

E-print Network

target companies, job titles or cities (include zip codes) 2.) Fill out form completely requesting contacts? Identify target company and city where you would like a contact: Identify target city you School of Engineering __Aerospace __Biomedical __Chemical __Civil __Computer __Electrical __Engineering

Rollins, Andrew M.

37

Barrier height determination on Schottky contacts formed at the back contact-semiconductor interface of degraded solar cells  

NASA Technical Reports Server (NTRS)

A method is described of determining an equivalent circuit for solar cells which have degraded as a result of the formation of a rectifying Schottky barrier at the back contact. An excellent fit of experimental data has been achieved using SCEPTRE with an equivalent circuit derived from the shape of the measured current voltage characteristics. One key parameter of the Schottky barrier diode, the reverse saturation current, can be used to determine the barrier potential. The barrier potential increases as the cell is stressed with 0.5 volts being a typical experimentally determined value for a degraded cell.

Misiakos, K.; Lathrop, J. W.

1984-01-01

38

Structure of Apo- and Monometalated Forms of NDM-1—A Highly Potent Carbapenem-Hydrolyzing Metallo-?-Lactamase  

PubMed Central

The New Delhi Metallo-?-lactamase (NDM-1) gene makes multiple pathogenic microorganisms resistant to all known ?-lactam antibiotics. The rapid emergence of NDM-1 has been linked to mobile plasmids that move between different strains resulting in world-wide dissemination. Biochemical studies revealed that NDM-1 is capable of efficiently hydrolyzing a wide range of ?-lactams, including many carbapenems considered as “last resort” antibiotics. The crystal structures of metal-free apo- and monozinc forms of NDM-1 presented here revealed an enlarged and flexible active site of class B1 metallo-?-lactamase. This site is capable of accommodating many ?-lactam substrates by having many of the catalytic residues on flexible loops, which explains the observed extended spectrum activity of this zinc dependent ?-lactamase. Indeed, five loops contribute “keg” residues in the active site including side chains involved in metal binding. Loop 1 in particular, shows conformational flexibility, apparently related to the acceptance and positioning of substrates for cleavage by a zinc-activated water molecule. PMID:21931780

Kim, Youngchang; Sacchettini, James; Joachimiak, Andrzej

2011-01-01

39

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

40

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

PubMed

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

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

2011-01-01

41

5/29/13 Questions? Contact: employee.services@yale.edu Page 1 of 2 Form 3501 FR.31  

E-print Network

5/29/13 Questions? Contact: employee.services@yale.edu Page 1 of 2 Form 3501 FR.31 Termination of Employment: U P I Reason for Termination: Retirement Resignation Fixed Duration Discharge Layoff Casual Other: NetID: Send email to user.accounts@yale.edu (Note: Terminating access to the employee's Net

42

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

43

Ion Channel-Forming Alamethicin Is a Potent Elicitor of Volatile Biosynthesis and Tendril Coiling. Cross Talk between Jasmonate and Salicylate Signaling in Lima Bean1  

PubMed Central

Alamethicin (ALA), a voltage-gated, ion channel-forming peptide mixture from Trichoderma viride, is a potent elicitor of the biosynthesis of volatile compounds in lima bean (Phaseolus lunatus). Unlike elicitation with jasmonic acid or herbivore damage, the blend of substances emitted comprises only the two homoterpenes, 4,11-dimethylnona-1,3,7-triene and 4,8,12-trimethyltrideca-1,3,7,11-tetraene, and methyl salicylate. Inhibition of octadecanoid signaling by aristolochic acid and phenidone as well as mass spectrometric analysis of endogenous jasmonate demonstrate that ALA induces the biosynthesis of volatile compounds principally via the octadecanoid-signaling pathway (20-fold increase of jasmonic acid). ALA also up-regulates salicylate biosynthesis, and the time course of the production of endogenous salicylate correlates well with the appearance of the methyl ester in the gas phase. The massive up-regulation of the SA-pathway (90-fold) interferes with steps in the biosynthetic pathway downstream of 12-oxophytodienoic acid and thereby reduces the pattern of emitted volatiles to compounds previously shown to be induced by early octadecanoids. ALA also induces tendril coiling in various species like Pisum, Lathyrus, and Bryonia, but the response appears to be independent from octadecanoid biosynthesis, because inhibitors of lipoxygenase and phospholipase A2 do not prevent the coiling reaction. PMID:11154344

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

2001-01-01

44

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

45

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

46

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

47

Atmospherically stable nanoscale zero-valent iron particles formed under controlled air contact: characteristics and reactivity.  

PubMed

Atmospherically stable NZVI (nanoscale zero-valent iron) particles were produced by modifying shell layers of Fe(H2) NZVI particles (RNIP-10DS) by using a controlled air contact method. Shell-modified NZVI particles were resistant to rapid aerial oxidation and were shown to have TCE degradation rate constants that were equivalent to 78% of those of pristine NZVI particles. Fe(H2) NZVI particles that were vigorously contacted with air (rapidly oxidized) showed a substantially compromised reactivity. Aging of shell-modified particles in water for one day resulted in a rate increase of 54%, implying that depassivation of the shell would play an important role in enhancing reactivity. Aging of shell-modified particles in air led to rate decreases by 14% and 46% in cases of one week and two months of aging, respectively. A series of instrumental analyses using transmission electron microscopy, X-ray diffractography, X-ray photoelectron spectroscopy, and X-ray absorption near-edge structure showed that the shells of modified NZVI particles primarily consisted of magnetite (Fe(3)O(4)). Analyses also implied that the new magnetite layer produced during shell modification was protective against shell passivation. Aging of shell-modified particles in water yielded another major mineral phase, goethite (alpha-FeOOH), whereas aging in air produced additional shell phases such as wustite (FeO), hematite (alpha-Fe(2)O(3)), and maghemite (gamma-Fe(2)O(3)). PMID:20136088

Kim, Hong-Seok; Ahn, Jun-Young; Hwang, Kyung-Yup; Kim, Il-Kyu; Hwang, Inseong

2010-03-01

48

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

NASA Technical Reports Server (NTRS)

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

Pepper, S. V.

1974-01-01

49

Induction of Ca2+-Calmodulin Signaling by Hard-Surface Contact Primes Colletotrichum gloeosporioides Conidia To Germinate and Form Appressoria  

PubMed Central

Hard-surface contact primes the conidia of Colletotrichum gloeosporioides to respond to plant surface waxes and a fruit-ripening hormone, ethylene, to germinate and form the appressoria required for infection of the host. Our efforts to elucidate the molecular events in the early phase of the hard-surface contact found that EGTA (5 mM) and U73122 (16 nM), an inhibitor of phospholipase C, inhibited (50%) germination and appressorium formation. Measurements of calmodulin (CaM) transcripts with a CaM cDNA we cloned from C. gloeosporioides showed that CaM was induced by hard-surface contact maximally at 2 h and then declined; ethephon enhanced this induction. The CaM antagonist, compound 48/80, completely inhibited conidial germination and appressorium formation at a concentration of 3 ?M, implying that CaM is involved in this process. A putative CaM kinase (CaMK) cDNA of C. gloeosporioides was cloned with transcripts from hard-surface-treated conidia. A selective inhibitor of CaMK, KN93 (20 ?M), inhibited (50%) germination and appressorium formation, blocked melanization, and caused the formation of abnormal appressoria. Scytalone, an intermediate in melanin synthesis, reversed the inhibition of melanization but did not restore appressorium formation. The phosphorylation of 18- and 43-kDa proteins induced by hard-surface contact and ethephon was inhibited by the treatment with KN93. These results strongly suggest that hard-surface contact induces Ca2+-calmodulin signaling that primes the conidia to respond to host signals by germination and differentiation into appressoria. PMID:9748448

Kim, Yeon-Ki; Li, Daoxin; Kolattukudy, Pappachan E.

1998-01-01

50

Enhanced performance of a-IGZO thin-film transistors by forming AZO/IGZO heterojunction source/drain contacts  

NASA Astrophysics Data System (ADS)

A low-cost Al-doped ZnO (AZO) thin film was deposited by radio-frequency magnetron sputtering with different Ar/O2 flow ratios. The optical and electrical properties of an AZO film were investigated. A highly conductive AZO film was inserted between the amorphous InGaZnO (a-IGZO) channel and the metal Al electrode to form a heterojunction source/drain contact, and bottom-gate amorphous a-IGZO thin-film transistors (TFTs) with a high ? HfON gate dielectric were fabricated. The AZO film reduced the source/drain contact resistivity down to 79 ? cm. Enhanced device performance of a-IGZO TFT with Al/AZO bi-layer S/D electrodes (W/L = 500/40 µm) was achieved with a saturation mobility of 13.7 cm2 V-1 s-1, a threshold voltage of 0.6 V, an on-off current ratio of 4.7 × 106, and a subthreshold gate voltage swing of 0.25 V dec-1. It demonstrated the potential application of the AZO film as a promising S/D contact material for the fabrication of the high performance TFTs.

Zou, Xiao; Fang, Guojia; Wan, Jiawei; Liu, Nishuang; Long, Hao; Wang, Haolin; Zhao, Xingzhong

2011-05-01

51

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

PubMed

The sizes of unfolded proteins under highly denaturing conditions scale as N(0.59) with chain length. This suggests that denaturing conditions mimic good solvents, whereby the preference for favorable chain-solvent interactions causes intrachain interactions to be repulsive, on average. Beyond this generic inference, the broader implications of N(0.59) scaling for quantitative descriptions of denatured state ensembles (DSEs) remain unresolved. Of particular interest is the degree to which N(0.59) scaling can simultaneously accommodate intrachain attractions and detectable long-range contacts. Here we present data showing that the DSE of the N-terminal domain of the L9 (NTL9) ribosomal protein in 8.3 M urea lacks detectable secondary structure and forms expanded conformations in accord with the expected N(0.59) scaling behavior. Paramagnetic relaxation enhancements, however, indicate the presence of detectable long-range contacts in the denatured-state ensemble of NTL9. To explain these observations we used atomistic thermal unfolding simulations to identify ensembles whose properties are consistent with all of the experimental observations, thus serving as useful proxies for the DSE of NTL9 in 8.3 M urea. Analysis of these ensembles shows that residual attractions are present under mimics of good solvent conditions, and for NTL9 they result from low-likelihood, medium/long-range contacts between hydrophobic residues. Our analysis provides a quantitative framework for the simultaneous observation of N(0.59) scaling and low-likelihood long-range contacts for the DSE of NTL9. We propose that such low-likelihood intramolecular hydrophobic clusters might be a generic feature of DSEs that play a gatekeeping role to protect against aggregation during protein folding. PMID:23341588

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

2013-02-01

52

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

53

Highly functionalized and potent antiviral cyclopentane derivatives formed by a tandem process consisting of organometallic, transition-metal-catalyzed, and radical reaction steps.  

PubMed

A simple modular tandem approach to multiply substituted cyclopentane derivatives is reported, which succeeds by joining organometallic addition, conjugate addition, radical cyclization, and oxygenation steps. The key steps enabling this tandem process are the thus far rarely used isomerization of allylic alkoxides to enolates and single-electron transfer to merge the organometallic step with the radical and oxygenation chemistry. This controlled lineup of multiple electronically contrasting reactive intermediates provides versatile access to highly functionalized cyclopentane derivatives from very simple and readily available commodity precursors. The antiviral activity of the synthesized compounds was screened and a number of compounds showed potent activity against hepatitis?C and dengue viruses. PMID:25043655

Jagtap, Pratap R; Ford, Leigh; Deister, Elmar; Pohl, Radek; Císa?ová, Ivana; Hodek, Jan; Weber, Jan; Mackman, Richard; Bahador, Gina; Jahn, Ullrich

2014-08-11

54

Presenilin-1 Forms Complexes with the Cadherin\\/Catenin Cell–Cell Adhesion System and Is Recruited to Intercellular and Synaptic Contacts  

Microsoft Academic Search

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, ?-catenin, and ?-catenin, all components of adherens junctions. In confluent MDCK cells, PS1 forms complexes with cell surface E-cadherin; disruption of Ca2+-dependent cell–cell contacts reduces surface PS1 and the levels of PS1-E-cadherin complexes. PS1 overexpression

Anastasios Georgakopoulos; Philippe Marambaud; Spiros Efthimiopoulos; Junichi Shioi; Wen Cui; Heng-Chun Li; Michael Schütte; Ronald Gordon; Gay R Holstein; Giorgio Martinelli; Pankaj Mehta; Victor L Friedrich; Nikolaos K Robakis

1999-01-01

55

Synthesis, biological activity, and crystal structure of potent nonnucleoside inhibitors of HIV-1 reverse transcriptase that retain activity against mutant forms of the enzyme.  

PubMed

In an ongoing effort to develop novel and potent nonnucleoside HIV-1 reverse transcriptase (RT) inhibitors that are effective against the wild type (WT) virus and clinically observed mutants, 1,2-bis-substituted benzimidazoles were synthesized and tested. Optimization of the N1 and C2 positions of benzimidazole led to the development of 1-(2,6-difluorobenzyl)-2-(2,6-difluorophenyl)-4-methylbenzimidazole (1) (IC50 = 0.2 microM, EC50 = 0.44 microM, and TC50 >/= 100 against WT). This paper describes how substitution on the benzimidazole ring profoundly affects activity. Substituents at the benzimidazole C4 dramatically enhanced potency, while at C5 or C6 substituents were generally detrimental or neutral to activity, respectively. A 7-methyl analogue did not inhibit HIV-1 RT. Determination of the crystal structure of 1 bound to RT provided the basis for accurate modeling of additional analogues, which were synthesized and tested. Several derivatives were nanomolar inhibitors of wild-type virus and were effective against clinically relevant HIV-1 mutants. PMID:17663538

Morningstar, Marshall L; Roth, Thomas; Farnsworth, David W; Smith, Marilyn Kroeger; Watson, Karen; Buckheit, Robert W; Das, Kalyan; Zhang, Wanyi; Arnold, Eddy; Julias, John G; Hughes, Stephen H; Michejda, Christopher J

2007-08-23

56

Synthesis, Biological Activity, and Crystal Structure of Potent Nonnucleoside Inhibitors of HIV-1 Reverse Transcriptase That Retain Activity against Mutant Forms of the Enzyme†  

PubMed Central

In an ongoing effort to develop novel and potent nonnucleoside HIV-1 reverse transcriptase (RT) inhibitors that are effective against the wild type (WT) virus and clinically observed mutants, 1,2-bis-substituted benzimidazoles were synthesized and tested. Optimization of the N1 and C2 positions of benzimidazole led to the development of 1-(2,6-difluorobenzyl)-2-(2,6-difluorophenyl)-4-methylbenzimidazole (1) (IC50 = 0.2 ?M, EC50 = 0.44 ?M, and TC50 ? 100 against WT). This paper describes how substitution on the benzimidazole ring profoundly affects activity. Substituents at the benzimidazole C4 dramatically enhanced potency, while at C5 or C6 substituents were generally detrimental or neutral to activity, respectively. A 7-methyl analogue did not inhibit HIV-1 RT. Determination of the crystal structure of 1 bound to RT provided the basis for accurate modeling of additional analogues, which were synthesized and tested. Several derivatives were nanomolar inhibitors of wild-type virus and were effective against clinically relevant HIV-1 mutants. PMID:17663538

Morningstar, Marshall L.; Roth, Thomas; Farnsworth, David W.; Smith, Marilyn Kroeger; Watson, Karen; Buckheit, Robert W.; Das, Kalyan; Zhang, Wanyi; Arnold, Eddy; Julias, John G.; Hughes, Stephen H.; Michejda, Christopher J.

2010-01-01

57

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

58

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

NASA Astrophysics Data System (ADS)

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.

2013-11-01

59

Discovery of a Potent and Selective EGFR Inhibitor (AZD9291) of Both Sensitizing and T790M Resistance Mutations That Spares the Wild Type Form of the Receptor.  

PubMed

Epidermal growth factor receptor (EGFR) inhibitors have been used clinically in the treatment of non-small-cell lung cancer (NSCLC) patients harboring sensitizing (or activating) mutations for a number of years. Despite encouraging clinical efficacy with these agents, in many patients resistance develops leading to disease progression. In most cases, this resistance is in the form of the T790M mutation. In addition, EGFR wild type receptor inhibition inherent with these agents can lead to dose limiting toxicities of rash and diarrhea. We describe herein the evolution of an early, mutant selective lead to the clinical candidate AZD9291, an irreversible inhibitor of both EGFR sensitizing (EGFRm+) and T790M resistance mutations with selectivity over the wild type form of the receptor. Following observations of significant tumor inhibition in preclinical models, the clinical candidate was administered clinically to patients with T790M positive EGFR-TKI resistant NSCLC and early efficacy has been observed, accompanied by an encouraging safety profile. PMID:25271963

Finlay, M Raymond V; Anderton, Mark; Ashton, Susan; Ballard, Peter; Bethel, Paul A; Box, Matthew R; Bradbury, Robert H; Brown, Simon J; Butterworth, Sam; Campbell, Andrew; Chorley, Christopher; Colclough, Nicola; Cross, Darren A E; Currie, Gordon S; Grist, Matthew; Hassall, Lorraine; Hill, George B; James, Daniel; James, Michael; Kemmitt, Paul; Klinowska, Teresa; Lamont, Gillian; Lamont, Scott G; Martin, Nathaniel; McFarland, Heather L; Mellor, Martine J; Orme, Jonathon P; Perkins, David; Perkins, Paula; Richmond, Graham; Smith, Peter; Ward, Richard A; Waring, Michael J; Whittaker, David; Wells, Stuart; Wrigley, Gail L

2014-10-23

60

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

PubMed Central

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

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

2012-01-01

61

Lead-germanium ohmic contact on to gallium arsenide formed by the solid phase epitaxy of germanium: A microstructure study  

NASA Astrophysics Data System (ADS)

Driven by the remarkable growth in the telecommunication market, the demand for more complex GaAs circuitry continued to increase in the last decade. As a result, the GaAs industry is faced with new challenges in its efforts to fabricate devices with smaller dimensions that would permit higher integration levels. One of the limiting factors is the ohmic contact metallurgy of the metal semiconductor field effect transistor (MESFET), which, during annealing, induces a high degree of lateral diffusion into the substrate. Because of its limited reaction with the substrate, the Pd-Ge contact seems to be the most promising candidate to be used in the next generation of MESFET's. The Pd-Ge system belongs to a new class of ohmic contacts to compound semiconductors, part of an alloying strategy developed only recently, which relies on solid phase epitaxy (SPE) and solid phase regrowth to "un-pin" the Fermi level at the surface of the compound semiconductor. However, implementing this alloy into an integrated process flow proved to be difficult due to our incomplete understanding of the microstructure evolution during annealing and its implications on the electrical properties of the contact. The microstructure evolution and the corresponding solid state reactions that take place during annealing of the Pd-Ge thin films on to GaAs were studied in connection with their effects on the electrical properties of the ohmic contact. The phase transformations sequence, transition temperatures and activation energies were determined by combining differential scanning calorimetry (DSC) for thermal analysis with transmission electron microscopy (TEM) for microstructure identification. In-situ TEM annealing experiments on the Pd/Ge/Pd/GaAs ohmic contact system have permitted real time determination of the evolution of contact microstructure. The kinetics of the solid state reactions, which occur during ohmic contact formation, were determined by measuring the grain growth rates associated with each phase from the videotape recordings. With the exception of the Pd-GaAs interactions, it was found that four phase transformations occur during annealing of the Pd:Ge thin films on top of GaAs. The microstructural information was correlated with specific ohmic contact resistivity measurements performed in accordance with the transmission line method (TLM) and these results demonstrated that the Ge SPE growth on top of GaAs renders the optimal electrical properties for the contact. By using the focused ion beam (FIB) method to produce microcantilever beams, the residual stress present in the thin film system was studied in connection with the microstructure. Although, the PdGe/epi-Ge/GaAs seemed to be the optimal microstructural configuration, the presence of PdGe at the interface with GaAs did not damage the contact resistivity significantly. These results made it difficult to establish a charge transport mechanism across the interface but they explained the wide processing window associated with this contact.

Radulescu, Fabian

62

Rod Bipolar Cells and Horizontal Cells Form Displaced Synaptic Contacts With Rods in the Outer Nuclear Layer of the nob2 Retina  

PubMed Central

The nob2 mouse carries a null mutation in the Cacna1f gene, which encodes the pore-forming subunit of the L-type calcium channel, Cav1.4. The loss of the electroretinogram b-wave in these mice suggests a severe reduction in transmission between photoreceptors and second-order neurons in the retina and supports a central role for the Cav1.4 calcium channel at photoreceptor ribbon synapses, to which it has been localized. Here we show that the loss of Cav1.4 leads to the aberrant outgrowth of rod bipolar cell dendrites and horizontal cell processes into the outer nuclear layer (ONL) of the nob2 retina and to the formation of ectopic synaptic contacts with rod photoreceptors in the ONL. Ectopic contacts are predominantly between rods and rod bipolar cells, with horizontal cell processes also present at some sites. Ectopic contacts contain apposed pre-and postsynaptic specializations, albeit with malformed synaptic ribbons. Cone photoreceptor terminals do not participate in ectopic contacts in the ONL. During retinal development, ectopic contacts appear in the days after eye opening, appearing progressively farther into the ONL at later postnatal stages. Ectopic contacts develop at the tips of rod bipolar cell dendrites and are less frequently associated with the tips of horizontal cell processes, consistent with the adult phenotype. The relative occurrence of pre- and postsynaptic markers in the ONL during development suggests a mechanism for the formation of ectopic synaptic contacts that is driven by the retraction of rod photoreceptor terminals and neurite outgrowth by rod bipolar cell dendrites. PMID:17111373

BAYLEY, PHILIPPA R.; MORGANS, CATHERINE W.

2014-01-01

63

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

DOEpatents

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

Gessert, Timothy A. (Conifer, CO)

1999-01-01

64

Free form source and mask optimization for negative tone resist development for 22nm node contact holes  

NASA Astrophysics Data System (ADS)

In this paper we demonstrate the feasibility of Negative Tone Development (NTD) process to pattern 22nm node contact holes leveraging freeform source and model based assist features. We demonstrate this combined technology with detailed simulation and wafer results. Analysis also includes further improvement achievable using a freeform source compared to a conventional standard source while keeping the mask optimization approaches the same. Similar studies are performed using the Positive Tone Development (PTD) process to demonstrate the benefits of the NTD process.

Coskun, Tamer H.; Dai, Huixiong; Kamat, Vishnu; Hsu, Ching-Mei; Santoro, Gaetano; Ngai, Chris; Reybrouck, Mario; Grozev, Grozdan; Huang, Hsu-Ting

2012-03-01

65

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

66

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

67

Crystal-contact engineering to obtain a crystal form of the Kelch domain of human Keap1 suitable for ligand-soaking experiments.  

PubMed

Keap1 is a substrate adaptor protein for a Cul3-dependent ubiquitin ligase complex and plays an important role in the cellular response to oxidative stress. It binds Nrf2 with its Kelch domain and thus triggers the ubiquitinylation and degradation of Nrf2. Oxidative stress prevents the degradation of Nrf2 and leads to the activation of cytoprotective genes. Therefore, Keap1 is an attractive drug target in inflammatory diseases. The support of a medicinal chemistry effort by structural research requires a robust crystallization system in which the crystals are preferably suited for performing soaking experiments. This facilitates the generation of protein-ligand complexes in a routine and high-throughput manner. The structure of human Keap1 has been described previously. In this crystal form, however, the binding site for Nrf2 was blocked by a crystal contact. This interaction was analysed and mutations were introduced to disrupt this crystal contact. One double mutation (E540A/E542A) crystallized in a new crystal form in which the binding site for Nrf2 was not blocked and was accessible to small-molecule ligands. The crystal structures of the apo form of the mutated Keap1 Kelch domain (1.98 Å resolution) and of the complex with an Nrf2-derived peptide obtained by soaking (2.20 Å resolution) are reported. PMID:23722832

Hörer, Stefan; Reinert, Dirk; Ostmann, Katja; Hoevels, Yvette; Nar, Herbert

2013-06-01

68

Contact sensitivity induced in mice by methylene bisphenyl diisocyanate.  

PubMed

An experimental model of contact sensitivity has been developed in C57BL/6 mice using methylene bisphenyl diisocyanate (MDI), a raw material of polyurethane resins. Sensitization through a single epidermal application of 1% MDI solution in ethyl acetate to the backs of the mice resulted in marked ear swelling. The time course of the swelling was characteristic of delayed-type hypersensitivity and the increment of the ear thickness was compatible with that induced by toluene diisocyanate (TDI). Passive transfer of the MDI-induced contact sensitivity was successfully achieved using lymphocytes from the lymph nodes of MDI-sensitized syngeneic mice, and the effector cells were found to be T cells. Cross reaction between MDI and TDI has shown that MDI is not only a potent contact sensitizer but also can form a contact sensitizer group together with TDI. PMID:2827956

Tanaka, K; Takeoka, A; Nishimura, F; Hanada, S

1987-10-01

69

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, with the fall meeting held on campus and the spring meeting held at various locations throughout Texas. Social Sciences at Texas A&M University by joining the COADC! Individual ($1,000) Corporate ($2,000) Allows for 2 representatives A check for dues is enclosed. I will pay monthly through the Texas A

70

Voltammetric studies on the potent carcinogen, 7,12-dimethylbenz[ a]anthracene: Adsorptive stripping voltammetric determination in bulk aqueous forms and human urine samples and detection of DNA interaction on pencil graphite electrode  

Microsoft Academic Search

7,12-Dimethylbenz[a]anthracene (DMBA), is a widely studied polycyclic aromatic hydrocarbon that has long been recognized as a very potent carcinogen. Initially, the electrochemical oxidation of DMBA at the glassy carbon and pencil graphite electrodes in non-aqueous media (dimethylsulphoxide with lithium perchlorate) was studied by cyclic voltammetry. DMBA was irreversibly oxidized in two steps at high positive potentials, resulting in the ill-resolved

Y. Yard?m; E. Keskin; A. Levent; M. Özsöz; Z. ?entürk

2010-01-01

71

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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

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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

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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:

75

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

NASA Astrophysics Data System (ADS)

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

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

76

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  

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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

77

Islamism in Azerbaijan: How Potent?  

Microsoft Academic Search

Azerbaijan is deemed to be the most secular of all post-Soviet Muslim counties. Nevertheless, growing independent Islamic activism, inspired by the international Islamic discourse and helped by foreign Islamic actors, and combined with a repressive regime response to this activity carried out under the banner of antiterrorism may contribute to make Islamism a potent factor in Azerbaijan. This article maps

Julie Wilhelmsen

2009-01-01

78

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

ERIC Educational Resources Information Center

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

Muller, Floris

2012-01-01

79

Theory of Contact Resistance  

NASA Astrophysics Data System (ADS)

Electrical contact is an important issue for high power microwave sources, wire-array Z pinches, field emitters, and metal-insulator-vacuum junctions. Because of the surface roughness on a microscopic scale, true contact between two pieces of metal occurs only on the asperities of the two contacting surfaces. This gives rise to contact resistance [1]. We have developed a novel analytic theory of contact resistance of an asperity of transverse dimension (a) and finite axial length (h) connecting two metal blocks. For asperity of rectangular, cylindrical or funnel shape, we find that the contact resistance is of the form R[1+p(h/a)] where R is the corresponding h=0 ``a-spot'' theory limit of Holm [1] and Timsit [2], p has a simple form which we have verified against electrostatic code results. This higher-dimensional treatment links the contact resistance to the geometrical deformations in response to an applied pressure, and to the hardness of the material. This work is supported by Sandia, AFOSR, AFRL, L-3, and Northrop-Grumman. [1] R. Holm, Electric Contact (Springer-Verlag, 1967). [2] R. S. Timsit, IEEE Trans. Components Packaging Tech. 22, 85 (1999).

Tang, Wilkin; Lau, Y. Y.; Gilgenbach, R. M.; Gomez, M. R.; Zier, J.

2008-11-01

80

Voltammetric studies on the potent carcinogen, 7,12-dimethylbenz[a]anthracene: Adsorptive stripping voltammetric determination in bulk aqueous forms and human urine samples and detection of DNA interaction on pencil graphite electrode.  

PubMed

7,12-Dimethylbenz[a]anthracene (DMBA), is a widely studied polycyclic aromatic hydrocarbon that has long been recognized as a very potent carcinogen. Initially, the electrochemical oxidation of DMBA at the glassy carbon and pencil graphite electrodes in non-aqueous media (dimethylsulphoxide with lithium perchlorate) was studied by cyclic voltammetry. DMBA was irreversibly oxidized in two steps at high positive potentials, resulting in the ill-resolved formation of a couple with a reduction and re-oxidation wave at much lower potentials. Special attention was given to the use of adsorptive stripping voltammetry together with a medium exchange procedure on disposable pencil graphite electrode in aqueous solutions over the pH range of 3.0-9.0. The response was characterized with respect to pH of the supporting electrolyte, pre-concentration time and accumulation potential. Using square-wave stripping mode, the compound yielded a well-defined voltammetric response in acetate buffer, pH 4.8 at +1.15V (vs. Ag/AgCl) (a pre-concentration step being carried out at a fixed potential of +0.60V for 360s). The process could be used to determine DMBA concentrations in the range 2-10nM, with an extremely low detection limit of 0.194nM (49.7ngL(-1)). The applicability to assay of spiked human urine samples was also illustrated. Finally, the interaction of DMBA with fish sperm double-stranded DNA based on decreasing of the oxidation signal of adenine base was studied electrochemically by using differential pulse voltammetry with a pencil graphite electrode at the surface and also in solution. The favorable signal-to-noise characteristics of biosensor resulted in low detection limit (ca. 46nM) following a 300-s interaction. These results displayed that the electrochemical DNA-based biosensor could be used for the sensitive, rapid, simple and cost effective detection of DMBA-DNA interaction. PMID:20006098

Yardim, Y; Keskin, E; Levent, A; Ozsöz, M; Sentürk, Z

2010-01-15

81

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82

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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:

83

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:

84

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

85

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86

Thermal stability study of Cr/Au contact formed on n-type Ga-polar GaN, N-polar GaN, and wet-etched N-polar GaN surfaces  

NASA Astrophysics Data System (ADS)

The electrical characteristics and thermal stability of a Cr/Au contact formed on n-type Ga-polar (0 0 0 1) GaN, N-polar GaN, and wet-etched N-polar GaN were investigated. As-deposited Cr/Au showed a nearly ohmic contact behavior for all samples, i.e., the specific contact resistance was 3.2 × 10-3, 4.3 × 10-4, and 1.1 × 10-3 ? cm2 for the Ga-polar, flat N-polar, and roughened N-polar samples, respectively. However, thermal annealing performed at 250 °C for 1 min in a N2 ambient led to a significant degradation of contact, i.e., the contact resistance increased by 186, 3260, and 2030% after annealing for Ga-polar, flat N-polar, and roughened N-polar samples, respectively. This could be due to the different disruption degree of Cr/Au and GaN interface after annealing, i.e., the insignificant interfacial reaction occurred in the Ga-polar sample, while out-diffusion of Ga and N atoms was clearly observed in N-polar samples.

Choi, Yunju; Kim, Yangsoo; Ahn, Kwang-Soon; Kim, Hyunsoo

2014-10-01

87

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

88

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

89

The minor groove-binding agent ELB-21 forms multiple interstrand and intrastrand covalent cross-links with duplex DNA and displays potent bactericidal activity against methicillin-resistant Staphylococcus aureus  

PubMed Central

Objectives The antistaphylococcal pyrrolobenzodiazepine dimer ELB-21 forms multiple adducts with duplex DNA through covalent interactions with appropriately spaced guanine residues; it is now known to form interstrand and intrastrand adducts with oligonucleotide sequences of variable length. We determined the DNA sequence preferences of ELB-21 in relation to its capacity to exert a bactericidal effect by damaging DNA. Methods Formation of adducts by ELB-21 and 12- to 14-mer DNA duplexes was investigated using ion-pair reversed phase liquid chromatography and mass spectrometry. Drug-induced changes in gene expression were measured in prophage-free Staphylococcus aureus RN4220 by microarray analysis. Results ELB-21 preferentially formed intrastrand adducts with guanines separated by three nucleotide base pairs. Interstrand and intrastrand adducts were formed with duplexes both longer and shorter than the preferred target sequences. ELB-21 elicited rapid bactericidal effects against prophage-carrying and prophage-free S. aureus strains; cell lysis occurred following activation and release of resident prophages. Killing appeared to be due to irreparable damage to bacterial DNA and susceptibility to ELB-21 was governed by the capacity of staphylococci to repair DNA lesions through induction of the SOS DNA damage response mediated by the RecA-LexA pathway. Conclusions The data support the contention that ELB-21 arrests DNA replication, eliciting formation of ssDNA-RecA filaments that inactivate LexA, the SOS repressor, and phage repressors such as Cl, resulting in activation of the DNA damage response and de-repression of resident prophages. Above the MIC threshold, DNA repair is ineffective. PMID:21393142

Rosado, Helena; Rahman, Khondaker M.; Feuerbaum, Eva-Anne; Hinds, Jason; Thurston, David E.; Taylor, Peter W.

2011-01-01

90

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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.

91

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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

92

Multiple clusters of release sites formed by individual thalamic afferents onto cortical interneurons ensure reliable transmission  

PubMed Central

Summary Thalamic afferents supply the cortex with sensory information by contacting both excitatory neurons and inhibitory interneurons. Interestingly, thalamic contacts with interneurons constitute such a powerful synapse that even one afferent can fire interneurons, thereby driving feedforward inhibition. However, the spatial representation of this potent synapse on interneuron dendrites is poorly understood. Using Ca imaging and electron microscopy we show that an individual thalamic afferent forms multiple contacts with the interneuronal proximal dendritic arbor, preferentially near branch points. More contacts are correlated with larger amplitude synaptic responses. Each contact, consisting of a single bouton, can release up to 7 vesicles simultaneously, resulting in graded and reliable Ca transients. Computational modeling indicates that the release of multiple vesicles at each contact minimally reduces the efficiency of the thalamic afferent in exciting the interneuron. This strategy preserves the spatial representation of thalamocortical inputs across the dendritic arbor over a wide range of release conditions. PMID:21745647

Bagnall, Martha W.; Hull, Court; Bushong, Eric A.; Ellisman, Mark H.; Scanziani, Massimo

2012-01-01

93

On the role of RhoA/ROCK signaling in contact guidance of bone-forming cells on anisotropic Ti6Al4V surfaces.  

PubMed

Patterned surfaces direct cell spatial dynamics, yielding cells oriented along the surface geometry, in a process known as contact guidance. The Rho family of GTPases controls the assembly of focal adhesions and cytoskeleton dynamics, but its role in modulating bone-cell alignment on patterned surfaces remains unknown. This article describes the interactions of two human cell types involved in osseointegration, specifically mesenchymal stem cells and osteoblasts, with submicron- or nano-scale Ti6Al4V grooved surfaces generated by mechanical abrasion. The surface chemistry of the alloy was not affected by grinding, ensuring that the differences found in cellular responses were exclusively due to changes in topography. Patterned surfaces supported cell growth and stimulated mesenchymal stem cell viability. Anisotropic surfaces promoted cell orientation and elongation along the grates. Both cell types oriented on nanometric surfaces with grooves of 150 nm depth and 2 ?m width. The number of aligned cells increased by approximately 30% on submicrometric grooves with sizes of about 1 ?m depth and 10 ?m width. Cells were treated with drugs that attenuate the activities of the GTPase RhoA and one of its downstream effectors, Rho-associated kinase (ROCK), and contact guidance of treated cells on the grooved surfaces was investigated. The data indicate that the RhoA/ROCK pathway is a key modulator of both mesenchymal stem cell and osteoblast orientation on nanometric surface features. RhoA and its effector participate in the alignment of mesenchymal stem cells on submicrometric grooves, but not of osteoblasts. These findings show that RhoA/ROCK signaling is involved in contact guidance of bone-related cells on metallic substrates, although to a varying extent depending on the specific cell type and the dimensions of the pattern. PMID:21115140

Calzado-Martín, A; Méndez-Vilas, A; Multigner, M; Saldaña, L; González-Carrasco, J L; González-Martín, M L; Vilaboa, N

2011-04-01

94

Cross-contact chain  

NASA Technical Reports Server (NTRS)

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

Lieneweg, Udo (Inventor)

1988-01-01

95

Celebrity Patients, VIPs, and Potentates  

PubMed Central

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

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

2002-01-01

96

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

97

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, ...

98

Contact Us  

Cancer.gov

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

99

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

100

Focal Contacts as Mechanosensors  

PubMed Central

The transition of cell–matrix adhesions from the initial punctate focal complexes into the mature elongated form, known as focal contacts, requires GTPase Rho activity. In particular, activation of myosin II–driven contractility by a Rho target known as Rho-associated kinase (ROCK) was shown to be essential for focal contact formation. To dissect the mechanism of Rho-dependent induction of focal contacts and to elucidate the role of cell contractility, we applied mechanical force to vinculin-containing dot-like adhesions at the cell edge using a micropipette. Local centripetal pulling led to local assembly and elongation of these structures and to their development into streak-like focal contacts, as revealed by the dynamics of green fluorescent protein–tagged vinculin or paxillin and interference reflection microscopy. Inhibition of Rho activity by C3 transferase suppressed this force-induced focal contact formation. However, constitutively active mutants of another Rho target, the formin homology protein mDia1 (Watanabe, N., T. Kato, A. Fujita, T. Ishizaki, and S. Narumiya. 1999. Nat. Cell Biol. 1:136–143), were sufficient to restore force-induced focal contact formation in C3 transferase-treated cells. Force-induced formation of the focal contacts still occurred in cells subjected to myosin II and ROCK inhibition. Thus, as long as mDia1 is active, external tension force bypasses the requirement for ROCK-mediated myosin II contractility in the induction of focal contacts. Our experiments show that integrin-containing focal complexes behave as individual mechanosensors exhibiting directional assembly in response to local force. PMID:11402062

Riveline, Daniel; Zamir, Eli; Balaban, Nathalie Q.; Schwarz, Ulrich S.; Ishizaki, Toshimasa; Narumiya, Shuh; Kam, Zvi; Geiger, Benjamin; Bershadsky, Alexander D.

2001-01-01

101

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

102

JKR adhesion in cylindrical contacts  

NASA Astrophysics Data System (ADS)

Planar JKR adhesive solutions use the half-plane assumption and do not permit calculation of indenter approach or visualization of adhesive force-displacement curves unless the contact is periodic. By considering a conforming cylindrical contact and using an arc crack analogy, we obtain closed-form indenter approach and load-contact size relations for a planar adhesive problem. The contact pressure distribution is also obtained in closed-form. The solutions reduce to known cases in both the adhesion-free and small-contact solution ( Barquins, 1988) limits. The cylindrical system shows two distinct regimes of adhesive behavior; in particular, contact sizes exceeding the critical (maximum) size seen in adhesionless contacts are possible. The effects of contact confinement on adhesive behavior are investigated. Some special cases are considered, including contact with an initial neat-fit and the detachment of a rubbery cylinder from a rigid cradle. A comparison of the cylindrical solution with the half-plane adhesive solution is carried out, and it indicates that the latter typically underestimates the adherence force. The cylindrical adhesive system is novel in that it possesses stable contact states that may not be attained even on applying an infinite load in the absence of adhesion.

Sundaram, Narayan; Farris, T. N.; Chandrasekar, S.

2012-01-01

103

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

PubMed

Specific sugar residues and their linkages form the basis of molecular recognition for interactions of glycoproteins with other biomolecules. Seemingly small changes, like the addition of a single monosaccharide in the covalently attached glycan component of glycoproteins, can greatly affect these interactions. For instance, the sialic acid capping of glycans affects protein-ligand binding involved in cell-cell and cell-matrix interactions. CD44 is a single-pass transmembrane glycoprotein whose binding with its carbohydrate ligand hyaluronan (HA), an extracellular matrix component, mediates processes such as leukocyte homing, cell adhesion, and tumor metastasis. This binding is highly regulated by glycosylation of the N-terminal extracellular hyaluronan-binding domain (HABD); specifically, sialic acid capped N-glycans of HABD inhibit ligand binding. However, the molecular mechanism behind this sialic acid mediated regulation has remained unknown. Two of the five N-glycosyation sites of HABD have been previously identified as having the greatest inhibitory effect on HA binding, but only if the glycans contain terminal sialic acid residues. These two sites, Asn25 and Asn120, were chosen for in silico glycosylation in this study. Here, from extensive standard molecular dynamics simulations and biased simulations, we propose a molecular mechanism for this behavior based on spontaneously-formed charge-paired hydrogen bonding interactions between the negatively-charged sialic acid residues and positively-charged Arg sidechains known to be critically important for binding to HA, which itself is negatively charged. Such intramolecular hydrogen bonds would preclude associations critical to hyaluronan binding. This observation suggests how CD44 and related glycoprotein binding is regulated by sialylation as cellular environments fluctuate. Proteins 2014; 82:3079-3089. © 2014 Wiley Periodicals, Inc. PMID:25116630

Faller, Christina E; Guvench, Olgun

2014-11-01

104

Rational Design of a Potent Anticoagulant Thrombin*  

E-print Network

Rational Design of a Potent Anticoagulant Thrombin* Received for publication, October 23, 2000 Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110 Thrombin acts of thrombin in the blood poses the challenge to turn the enzyme into a potent anticoagu- lant by selectively

Di Cera, Enrico

105

The potent enhancer activity of the polycythemic strain of spleen focus-forming virus in hematopoietic cells is governed by a binding site for Sp1 in the upstream control region and by a unique enhancer core motif, creating an exclusive target for PEBP/CBF.  

PubMed Central

The polycythemic strain of the spleen focus-forming virus (SFFVp) contains the most potent murine retroviral enhancer configuration known so far for gene expression in myeloerythroid hematopoietic cells. In the present study, we mapped two crucial elements responsible for the high activity of the SFFVp enhancer to an altered upstream control region (UCR) containing a GC-rich motif (5'-GGGCGGG-3') and to a unique enhancer core (5'-TGCGGTC-3'). Acquisition of these motifs accounts for half of the activity of the complete retroviral enhancer in hematopoietic cells, irrespective of the developmental stage or lineage. Furthermore, the UCR motif contains the major determinant for the enhancer activity of SFFVp in embryonic stem (ES) cells. Using electrophoretic mobility shift assays, we show that the UCR of SFFVp, but not of Friend murine leukemia virus, is targeted by the ubiquitous transcriptional activator, Sp1. The core motif of SFFVp creates a specific and high-affinity target for polyomavirus enhancer binding protein/core binding factor (PEBP/CBF) and excludes access of CAAT/enhancer binding protein. Cotransfection experiments with ES cells imply that PEBP/CBF cooperates with the neighboring element, LVb (the only conserved Ets consensus in the SFFVp enhancer), and that the Sp1 motif in the UCR stimulates transactivation through the Ets-PEBP interaction. Putative secondary structures of the retroviral enhancers are proposed based on these data. PMID:9261349

Baum, C; Itoh, K; Meyer, J; Laker, C; Ito, Y; Ostertag, W

1997-01-01

106

Potent Anti-Cancer Toxin  

Cancer.gov

SKIP ALL NAVIGATION SKIP TO SUB MENU Search Site Technology Transfer Center of the National Cancer Institute Standard Forms & Agreements Co-Development & Resources Careers & Training Intellectual Property & Inventions About TTC Overview Biomarkers Available

107

Contact allergy to food.  

PubMed

Contact allergies to foods, spices, and food additives can occur to individuals in the workplace or at home. Seven different reaction types have been described. These include irritant contact dermatitis, allergic contact dermatitis, contact urticaria, protein contact dermatitis, phototoxic contact dermatitis, photo-allergic contact dermatitis, and systemic contact dermatitis. The causes of each of these are reviewed and an approach to the diagnosis and management of contact allergy to foods, spices, and food additives is formulated. PMID:15327475

Brancaccio, Ronald R; Alvarez, Marcy S

2004-01-01

108

Contact Information  

Cancer.gov

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

109

Designed Potent Multivalent Chemoattractants for Escherichia coli$  

E-print Network

Designed Potent Multivalent Chemoattractants for Escherichia coli$ Jason E. Gestwicki, Laura E small molecules (i.e., carbohydrates, amino acids) interact with bacterial chemoreceptors. Although bacterial chemotaxis has been the subject of intense investigations, few have explored the influence

Cairo, Christopher W.

110

beta Endorphin is a Potent Analgesic Agent  

Microsoft Academic Search

beta -Endorphin, an opiate-like peptide, has potent antinociceptive properties when it is administered directly into the brain and assayed in the tail-flick, hot-plate, and writhing tests in mice and in the wet shake test in rats. On a molar basis, beta -endorphin is 18 to 33 times more potent than morphine and its actions are blocked by the specific opiate

Horace H. Loh; L. F. Tseng; Eddie Wei; Choh Hao Li

1976-01-01

111

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

112

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,

113

Contact Lens Risks  

MedlinePLUS

... List of Contact Lenses Links Report a Problem Contact Lens Risks Wearing contact lenses puts you at ... redness blurred vision swelling pain Serious Hazards of Contact Lenses Symptoms of eye irritation can indicate a ...

114

Hospitality Booking Form Your Name Contact No  

E-print Network

, Coffee & Water) 2.71 £ Beverage 3 (Tea, Coffee, Water & Biscuits) 4.08 £ Working Breakfast 1 - 6.52 £ Hot Breakfast Roll - 1.33 £ Working Lunch 1 - 7.43 £ Working Lunch 2 - 9.75 £ Working Lunch 3 - 10.88 £ Working Lunch 4 - 13.50 £ Packed Lunch - 6.57 £ Cold Fork Buffet 1 - 11.05 £ Cold Fork Buffet 2 - 17.86 £ Daily

Maizels, Rick

115

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

116

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

117

Sinterless Formation Of Contacts On Indium Phosphide  

NASA Technical Reports Server (NTRS)

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

Weizer, Victor G.; Fatemi, Navid S.

1995-01-01

118

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

119

Symmetries of Contact Metric Manifolds  

Microsoft Academic Search

We study the Lie algebra of infinitesimal isometries on compact Sasakian and K-contact manifolds. On a Sasakian manifold which is not a space form or 3-Sasakian, every Killing vector field is an infinitesimal automorphism of the Sasakian structure. For a manifold with K-contact structure, we prove that there exists a Killing vector field of constant length which is not an

Florin Belgun; Andrei Moroianu; Uwe Semmelmann

2003-01-01

120

Vapor-liquid contacting system  

SciTech Connect

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

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

1981-10-27

121

Rolling-Contact Rheostat  

NASA Technical Reports Server (NTRS)

Contact noise in rheostats and potentiometers reduced by rolling contact design. Smooth rolling action eliminates sporadic variations in resistance caused by bouncing and stick/slip motion of conventional sliding contacts.

Ruoff, C. F.

1985-01-01

122

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

123

Dependence of contact resistance on current for ohmic contacts to quantized Hall resistors  

Microsoft Academic Search

The dependence of contact resistance on current has been measured for a large number of ohmic contacts to quantized Hall resistors under quantum Hall effect conditions. Five different functional forms of current dependence are observed at low currents. The trend from best to worst quality can be correlated with the density of defects in the contact, regardless of the physical

Kevin C. Lee

1999-01-01

124

Roughness effects on contact angle measurements  

NASA Astrophysics Data System (ADS)

We have developed a simple and economical procedure to demonstrate the effects of roughness and wetting fraction on the equilibrium contact angles of liquid droplets on solid surfaces. Contact angles for droplets placed on a rough surface, which wet only a portion of the surface, are larger than the contact angles of droplets formed by condensation of steam, which wet the surface more completely. These contact angle data facilitate assessments of changes in true surface area, due to surface roughening, as well as changes in the fractional contact areas of the water droplets, due to the formation of air pockets between the rough surface and the droplet.

Ryan, Bernard J.; Poduska, Kristin M.

2008-11-01

125

The Parasocial Contact Hypothesis  

Microsoft Academic Search

We propose a communication analogue to Allport's (1954) Contact Hypothesis called the Parasocial Contact Hypothesis (PCH). If people process mass-mediated parasocial interaction in a manner similar to interpersonal interaction, then the socially beneficial functions of intergroup contact may result from parasocial contact. We describe and test the PCH with respect to majority group members' level of prejudice in three studies,

Edward Schiappa; Peter B. Gregg; Dean E. Hewes

2005-01-01

126

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

127

Potent tyrosinase inhibitors from Trifolium balansae.  

PubMed

Trifolium balansae (Leguminosae) yielded a phytylester, phytyl-1-hexanoate, three steroids, stigmast-5-ene-3 beta,26-diol, stigmast-5-ene-3-ol and campesterol, and an alcohol, pentacosanol which were reported for the first time from T.balansae. The structures of the isolates were determined by 1D and 2D NMR techniques and MS spectroscopy. Compounds 1-5 were tested for their enzyme tyrosinase activity. While compounds 1 and 5 did not show any inhibition against the enzyme tyrosinase, compounds 2, 3, and 4 exhibited potent inhibition against tyrosinase. Highly potent (IC50 = 2.39 microM) inhibition was found by compound 2, when compared with the standard tyrosinase inhibitors Kojic acid and L-mimosine. PMID:16901809

Sabudak, Temine; Tareq Hassan Khan, Mahmut; Iqbal Choudhary, M; Oksuz, Sevil

2006-06-01

128

Quasi-Quantum Model of Potentization  

E-print Network

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

Marcin Molski

2009-11-23

129

Quasi-Quantum Model of Potentization  

E-print Network

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

Molski, Marcin

2009-01-01

130

College Timetable Representatives College Contact Contact Details  

E-print Network

College Timetable Representatives College Contact Contact Details Adult Continuing Education Fran) MedEducation.Unit@swansea.ac.uk College of Science costimetabling@swansea.ac.uk School of Management Lloyd F.J.Lloyd@swansea.ac.uk College of Arts & Humanities Ruth Lake R.Lake@swansea.ac.uk College

Harman, Neal.A.

131

Herschel and Planck contacts STFC contact  

E-print Network

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

132

Hazardous Materials Alert Departmental Contact(s)  

E-print Network

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

Hickman, Mark

133

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

134

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

2013-01-01

135

Screen printed interdigitated back contact solar cell  

NASA Astrophysics Data System (ADS)

Interdigitated back contact solar cells are made by screen printing dopant materials onto the back surface of a semiconductor substrate in a pair of interdigitated patterns. These dopant materials are then diffused into the substrate to form junctions having configurations corresponding to these patterns. Contacts having configurations which match the patterns are then applied over the junctions.

Baraona, C. R.; Mazaris, G. A.; Chai, A. T.

1984-10-01

136

Screen printed interdigitated back contact solar cell  

NASA Technical Reports Server (NTRS)

Interdigitated back contact solar cells are made by screen printing dopant materials onto the back surface of a semiconductor substrate in a pair of interdigitated patterns. These dopant materials are then diffused into the substrate to form junctions having configurations corresponding to these patterns. Contacts having configurations which match the patterns are then applied over the junctions.

Baraona, C. R.; Mazaris, G. A.; Chai, A. T. (inventors)

1984-01-01

137

Buying Cosmetic Contact Lenses?  

MedlinePLUS

... eye look of circle lenses, or switch your eye color from blue to violet for the day, cosmetic contactscontact lenses meant to change the way your eye looks rather than correct your vision — may seem ...

138

Glasses and Contact Lenses  

MedlinePLUS

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

139

Buying Contact Lenses  

MedlinePLUS

... regulated by both the FDA and the Federal Trade Commission (FTC). Before you buy any contact lenses ... label contact lens, the name of the manufacturer, trade name of the private label brand, and if ...

140

Contact solution algorithms  

NASA Technical Reports Server (NTRS)

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

Tielking, John T.

1989-01-01

141

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

142

Modeling Thermal Contact Resistance  

NASA Technical Reports Server (NTRS)

One difficulty in using cryocoolers is making good thermal contact between the cooler and the instrument being cooled. The connection is often made through a bolted joint. The temperature drop associated with this joint has been the subject of many experimental and theoretical studies. The low temperature behavior of dry joints have shown some anomalous dependence on the surface condition of the mating parts. There is also some doubts on how well one can extrapolate from the test samples to predicting the performance of a real system. Both finite element and analytic models of a simple contact system have been developed. The model assumes (a) the contact is dry (contact limited to a small portion of the total available area and the spaces in-between the actual contact patches are perfect insulators), (b) contacts are clean (conductivity of the actual contact is the same as the bulk), (c) small temperature gradients (the bulk conductance may be assumed to be temperature independent), (d) the absolute temperature is low (thermal radiation effects are ignored), and (e) the dimensions of the nominal contact area are small compared to the thickness of the bulk material (the contact effects are localized near the contact). The models show that in the limit of actual contact area much less than the nominal area (a much less than A), that the excess temperature drop due to a single point of contact scales as a(exp -1/2). This disturbance only extends a distance approx. A(exp 1/2) into the bulk material. A group of identical contacts will result in an excess temperature drop that scales as n(exp -1/2), where n is the number of contacts and n dot a is constant. This implies that flat rough surfaces will have a lower excess temperature drop than flat polished surfaces.

Kittel, Peter; Sperans, Joel (Technical Monitor)

1994-01-01

143

Non-contact measurement of contact wire  

NASA Astrophysics Data System (ADS)

The overhead contact system is the power supply unit of the electric locomotive. This article is to introduce our newly developed method to measure the height and pull out value of the contact wire. A carema dolly which can move on railway is applied to bear the weight of the measure equipment; two linear CCD cameras are installed on the dolly symmetrically about the midline of two rails. While the dolly move along the railway, two CCD cameras grasp the image synchronously, and a computer real-time process the images, the height and pull out value can be calculate out from the images.

Yi, Yaxing; Ye, Xuemei; Li, Zhongke; Yue, Kaiduan

2008-12-01

144

Contact changes near jamming  

NASA Astrophysics Data System (ADS)

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

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

2014-08-01

145

Contact Cheilitis – A Review  

Microsoft Academic Search

Contact dermatitis is a common cause of eczematous cheilitis. In a Singapore series, allergic contact dermatitis is commoner than irritant contact dermatitis. More females are affected than males. Eczematous cheilitis usually presents in the 3rd and 4th decades of life. Eczematous cheilitis tends to occur among office workers and professionals (50.5%). This is probably due to the more frequent use

C. L. Goh

2003-01-01

146

Takaaki Shiratori Contact Information  

E-print Network

Takaaki Shiratori Contact Information Disney Research, Pittsburgh, Walt Disney Imagineering 4720 Postdoctoral Associate October 2010 ­ Present Disney Research, Pittsburgh, Walt Disney Imagineering Pittsburgh

Treuille, Adrien

147

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 ...

148

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

149

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

Federal Register 2010, 2011, 2012, 2013

...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

150

Mechanistic Basis for the Potent Anti-angiogenic Activity of Semaphorin 3F  

PubMed Central

Neuropilin-1 (Nrp1), an essential type I transmembrane receptor, binds two secreted ligand families, Vascular Endothelial Growth Factor (VEGF) and class III Semaphorin (Sema3). VEGF-A and Sema3F have opposing roles in regulating Nrp1 vascular function in angiogenesis. VEGF-A functions as one of the most potent pro-angiogenic cytokines while Sema3F is a uniquely potent endogenous angiogenesis inhibitor. Sema3 family members require proteolytic processing by furin to enable competitive binding to Nrp1. We demonstrate that the furin processed C-terminal domain of Sema3F (C-furSema) potently inhibits VEGF-A dependent activation of endothelial cells. We find that this potent activity is due to unique hetero-bivalent engagement of Nrp1 by two distinct sites in the Sema3F C-terminal domain. One of the sites is the C-terminal arginine, liberated by furin cleavage, and the other is a novel upstream helical motif centered on the intermolecular disulfide. Using a novel chimeric C-furSema, we demonstrate that combining a single C-terminal arginine with the helical motif is necessary and sufficient for potent inhibition of VEGF-A binding to Nrp1. We further demonstrate that the multiple furin-processed variants of Sema3A, with altered proximity of the two binding motifs, have dramatically different potencies. This suggests that furin processing not only switches Sema3 into an activated form but, depending on the site processed, can also tune potency. These data establish the basis for potent competitive Sema3 binding to Nrp1 and provide a basis for the design of bivalent Nrp inhibitors. PMID:24079887

Guo, Hou-Fu; Li, Xiaobo; Parker, Matthew W.; Waltenberger, Johannes; Becker, Patrice M.; Vander Kooi, Craig W.

2013-01-01

151

Contact inhibition and malignancy  

Microsoft Academic Search

The role of contact inhibition in influencing the behaviour of malignant cells is discussed in a review. Although tissue culture cannot simulate the immense complexity of the conditions in vivo, some of the distinctive features of malignant invasion can be conveniently observed with this technique. The evidence derived from this technique indicates that defective contact inhibition of movement of malignant

M. Abercrombie

1979-01-01

152

NCI Staff Contacts  

Cancer.gov

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

153

NCI Staff Contacts  

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

154

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

155

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

156

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K24 Award, contact: Dr. Susan LimProgram DirectorE-mail: lims@mail.nih.gov Branch Phone:  (240)

157

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K08 Award, contact: Dr. Susan PerkinsProgram DirectorE-mail: perkinsu@mail.nih.gov Dr. Sonia

158

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 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: (240)

159

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K99/R00 Award, contact: Dr. Michael SchmidtProgram DirectorE-mail: mschmidt@mail.nih.gov Branch

160

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 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:  (240)276-5630 For

161

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K07 Award, contact: Dr. Susan N. PerkinsProgram DirectorE-mail: perkinsu@mail.nih.gov Branch

162

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application, contact: Dr. Michael SchmidtProgram DirectorE-mail: mschmidt@mail.nih.gov Dr. Mark DamicoProgram DirectorE-mail:

163

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K22 Award, contact: Dr. Sonia B. JakowlewProgram DirectorE-mail: jakowles@mail.nih.gov Branch

164

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 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. Susan

165

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 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) 276-5630Fax:

166

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 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

167

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 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

168

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the K12 Award, contact: Dr. Mark DamicoProgram DirectorE-mail: damicomw@mail.nih.gov Branch Telephone:

169

NCI Staff Contacts  

Cancer.gov

Updated: 05/28/2013 Updated: 05/28/2013 NCI Staff Contacts For additional information regarding policies and/or guidance in preparing an application for the R25T Award, contact: Dr. Susan N. PerkinsProgram DirectorE-mail: perkinsu@mail.nih.gov Branch

170

Contact Lens Solution Toxicity  

MedlinePLUS

... situations require immediate medical attention: Progressive vision loss Progressive pain Thick or pus-like discharge No improvement or worsening of your eye condition after 24 hours without the use of contact lenses or exposure to contact lens solutions Treatments Your ...

171

Using Intelligent User Interfaces to Support Contact Centre Operations  

Microsoft Academic Search

Seventeen percent of all calls received by contact centres are not resolved on the first call. Resolution of customer queries and transactions forms a pivotal role in the daily operations of most contact centres. The focus of this research is to develop a model that employs an intelligent user interface in order to improve the operations of a contact centre.

Akash Singh; Janet L Wesson

172

An Exceptionally Potent Inducer of Cytoprotective Enzymes  

PubMed Central

The Keap1/Nrf2/ARE pathway controls a network of cytoprotective genes that defend against the damaging effects of oxidative and electrophilic stress, and inflammation. Induction of this pathway is a highly effective strategy in combating the risk of cancer and chronic degenerative diseases, including atherosclerosis and neurodegeneration. An acetylenic tricyclic bis(cyano enone) bearing two highly electrophilic Michael acceptors is an extremely potent inducer in cells and in vivo. We demonstrate spectroscopically that both cyano enone functions of the tricyclic molecule react with cysteine residues of Keap1 and activate transcription of cytoprotective genes. Novel monocyclic cyano enones, representing fragments of rings A and C of the tricyclic compound, reveal that the contribution to inducer potency of the ring C Michael acceptor is much greater than that of ring A, and that potency is further enhanced by spatial proximity of an acetylenic function. Critically, the simultaneous presence of two cyano enone functions in rings A and C within a rigid three-ring system results in exceptionally high inducer potency. Detailed understanding of the structural elements that contribute to the reactivity with the protein sensor Keap1 and to high potency of induction is essential for the development of specific and selective lead compounds as clinically relevant chemoprotective agents. PMID:20801881

Dinkova-Kostova, Albena T.; Talalay, Paul; Sharkey, John; Zhang, Ying; Holtzclaw, W. David; Wang, Xiu Jun; David, Emilie; Schiavoni, Katherine H.; Finlayson, Stewart; Mierke, Dale F.; Honda, Tadashi

2010-01-01

173

Potent interaction of flavopiridol with MRP1  

PubMed Central

The multidrug resistance protein 1 (MRP1) is an ATP-dependent transport protein for organic anions, as well as neutral or positively charged anticancer agents. In this study we show that flavopiridol, a synthetic flavonoid currently studied in phase 1 trials for its anti-proliferative characteristics, interacts with MRP1 in a potent way. Flavopiridol, as well as other (iso)flavonoids stimulate the ATPase activity of MRP1 in a dose-dependent way at low micromolar concentrations. A new specific monoclonal antibody against MRP1 (MIB6) inhibits the (iso)flavonoid-induced ATPase activity of plasma membrane vesicles prepared from the MRP1 overexpressing cell line GLC4/ADR. The accumulation of daunorubicin in GLC4/ADR cells is increased by flavopiridol and by other non-glycosylated (iso)flavonoids that interact with MRP1 ATPase activity. However, flavopiridol is the only tested compound that affects the daunorubicin accumulation when present at concentrations below 1 ?M. Glycosylated (iso)flavonoids do not affect MRP1-mediated transport or ATPase activity. Finally, MRP1 overexpressing and transfected cells are resistant to flavopiridol, but not to other (iso)flavonoids tested. These findings may be of relevance for the development of anticancer therapies with flavopiridol. © 1999 Cancer Research Campaign PMID:10496352

Hooijberg, J H; Broxterman, H J; Scheffer, G L; Vrasdonk, C; Heijn, M; Jong, M C de; Scheper, R J; Lankelma, J; Pinedo, HM

1999-01-01

174

Contact Information UW Tacoma Cashier's Office  

E-print Network

Contact Information UW Tacoma Cashier's Office 1900 Commerce Street Attn: Cashier's office Box; there is a $10 service charge for participating that is due with the first payment. You may download Payment Plan Enrollment Form is only available online. Please download the form, complete and submit

Kaminsky, Werner

175

ATBC Study - Questionnaires and Forms  

Cancer.gov

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

176

Service Learning Course Designation Application Form For the results, install the latest version of Adobe Reader. Adobe Reader is a free application; users should contact their local IT support if  

E-print Network

Service Learning Course Designation Application Form For the results, install-based service learning will be required of each student in the course (must be a requirement for all students in section): #12;Service Learning Course

Sheridan, Jennifer

177

CONTACT 5-MANIFOLDS WITH SU(2)STRUCTURE  

Microsoft Academic Search

We consider 5-manifolds with a contact form arising from a hypo structure (9), which we call hypo-contact. We provide existence conditions for such a structure on an oriented hypersurface of a 6-manifold with a half-flat SU(3)-structure. For half-flat manifolds with a Killing vector field X preserving the SU(3)-structure we study the geometry of the orbits space. Moreover, we describe the

Luis C. de Andres; Marisa Fernandez; Anna Fino; Luis Ugarte

2009-01-01

178

Effect of Mg doping on increase in the life with low contact resistance of Ag-Pd alloy switching contacts in silicone vapor environments  

Microsoft Academic Search

When silicone vapor adsorbed on contact surfaces is subjected to high temperature due to electric discharge in the atmosphere, SiO2 is formed by chemical decomposition of the adsorbed silicone molecular. When SiO2 is formed on contact surfaces and is caught in the interface of contacts, contact failure is caused by an insulation property of SiO2. Newly developed contact material of

Terutaka Tamai; Akihiro Sato; Syuro Ito

2000-01-01

179

N-naphthoyl-?-naltrexamine (NNTA), a highly selective and potent activator of ?/?-opioid heteromers  

PubMed Central

Numerous G protein-coupled receptors (GPCRs) have been shown to form heteromeric receptors in cell-based assays. Among the many heteromers reported in the opioid receptor family are ?/?, ?/?, and ?/?. However, the in vivo physiological and behavioral relevance for the proposed heteromers have not yet been established. Here we report a unique example of a ligand, N-naphthoyl-?-naltrexamine (NNTA) that selectively activates heteromeric ?/?-opioid receptors in HEK-293 cells and induces potent antinociception in mice. NNTA was an exceptionally potent agonist in cells expressing ?/?-opioid receptors. Intriguingly, it was found to be a potent antagonist in cells expressing only ?-receptors. In the mouse tail-flick assay, intrathecal (i.t.) NNTA produced antinociception that was ~100-fold greater than by intracerebroventricular (i.c.v.) administration. The ?-antagonist, norBNI, decreased the i.t. potency, and the activity was virtually abolished in ?-opioid receptor knockout mice. No tolerance was induced i.t., but marginal tolerance (3-fold) was observed via the i.c.v. route. Moreover, NNTA produced neither significant physical dependence nor place preference in the ED50 dose range. Taken together, this work provides an important pharmacologic tool for investigating the in vivo functional relevance of heteromeric ?/?-opioid receptors and suggests an approach to potent analgesics with fewer deleterious side effects. PMID:21385944

Yekkirala, Ajay S.; Lunzer, Mary M.; McCurdy, Christopher R.; Powers, Michael D.; Kalyuzhny, Alexander E.; Roerig, Sandra C.; Portoghese, Philip S.

2011-01-01

180

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

181

Antibiotic sensitization using biphenyl tetrazoles as potent inhibitors of Bacteroides fragilis metallo-?-lactamase  

Microsoft Academic Search

Background: High level resistance to carbapenem antibiotics in gram negative bacteria such as Bacteroides fragilis is caused, in part, by expression of a wide-spectrum metallo-?-lactamase that hydrolyzes the drug to an inactive form. Co-administration of metallo-?-lactamase inhibitors to resistant bacteria is expected to restore the antibacterial activity of carbapenems.Results: Biphenyl tetrazoles (BPTs) are a structural class of potent competitive inhibitors

Jeffrey H. Toney; Paula M. D. Fitzgerald; Nandini Grover-Sharma; Steven H. Olson; Walter J. May; Jon G. Sundelof; Dana E. Vanderwall; Kelly A. Cleary; Stephan K. Grant; Joseph K. Wu; John W. Kozarich; David L. Pompliano; Gail G. Hammond

1998-01-01

182

Preparation of imidazoles as potent calcitonin gene-related peptide (CGRP) antagonists.  

PubMed

Several new potent CGRP receptor antagonists have been prepared in which the amide bond of lead compound 1 has been replaced by bioisosteric imidazole moieties. Substitution at N-1 of the imidazole was optimized to afford compounds with comparable potency to that of lead 1. Conformational restraint of the imidazole to form tetrahydroimidazo[1,5-a]pyrazine 43 gave substantially improved permeability. PMID:23993336

Tora, George; Degnan, Andrew P; Conway, Charles M; Kostich, Walter A; Davis, Carl D; Pin, Sokhom S; Schartman, Richard; Xu, Cen; Widmann, Kimberly A; Macor, John E; Dubowchik, Gene M

2013-10-15

183

Characteristics of protein residue-residue contacts and their application in contact prediction.  

PubMed

Contact sites between amino acids characterize important structural features of a protein. We investigated characteristics of contact sites in a representative set of proteins and their relations between protein class or topology. For this purpose, we used a non-redundant set of 5872 protein domains, identically categorized by CATH and SCOP databases. The proteins represented alpha, beta, and alpha+beta classes. Contact maps of protein structures were obtained for a selected set of physical distances in the main backbone and separations in protein sequences. For each set a dependency between contact degree and distance parameters was quantified. We indicated residues forming contact sites most frequently and unique amino acid pairs which created contact sites most often within each structural class. Contact characteristics of specific topologies were compared to the characteristics of their protein classes showing protein groups with a distinguished contact characteristic. We showed that our results could be used to improve the performance of recent top contact predictor - direct coupling analysis. Our work provides values of contact site propensities that can be involved in bioinformatic databases. PMID:25374390

Wozniak, Pawel P; Kotulska, Malgorzata

2014-11-01

184

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.

2010-06-23

185

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

186

Contacts & Information Sources  

Cancer.gov

PLCO Background Information about PLCO Sponsoring Organization Participants/Eligibility PLCO Extended Follow-Up Etiology and Early Marker Studies Cancer Data Access System PLCO Publications Contacts & Information Sources PLCO participants who

187

Contact Information Appointments  

E-print Network

Professor Department of Sociology & Institute for Mathematical Behavioral Science University of California 2009 Summer Visiting postdoctoral fellow Department of Behavioral Science Hokkaido University SapporoContact Information Appointments Education Publications Awards 2171 Social Science Plaza

Stanford, Kyle

188

Occupational contact dermatitis.  

PubMed

The dermatologist should be aware of the many facets of occupational skin diseases, which can be caused by physical, chemical, and biological insults. The most common manifestation of occupational skin diseases is contact dermatitis (both irritant and allergic). Three factors point out the importance of occupational skin diseases as diseases that have a public health impact: 1) occupational skin diseases are common; 2) they often have a poor prognosis; and 3) they result in a noteworthy economic impact for society and for an individual. They are also diseases amenable to public health interventions. Specific industries and exposures may put a worker at risk of occupational contact dermatitis. The accuracy of the diagnosis of occupational contact dermatitis is related to the skill level, experience, and knowledge of the medical professional who makes the diagnosis and confirms the relationship with a workplace exposure. Prevention of occupational contact dermatitis is important, and a variety of prevention strategies are available. PMID:15186373

Lushniak, Boris D

2004-01-01

189

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

190

Irritant Contact Dermatitis  

MedlinePLUS

... contact dermatitis is the hands, though any body surface can be involved, including the genitals. Lesions can appear pink to red. In chronic cases, affected areas may develop scale and cracks. In acute cases, areas may have ...

191

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

192

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

193

Contact Heat Exchanger  

NASA Technical Reports Server (NTRS)

Fluid pressure controls contact between heat pipe and heat exchanger. Heat exchanger system in cross section provides contact interface between fluid system and heat pipe with easy assembly/disassembly of heat-pipe/ pumped-liquid system. Originally developed for use in space, new device applicable on Earth where fluid system is linked with heat pipe, where rapid assembly/disassembly required, or where high pressures or corrosive fluids used.

Fleming, M. L.; Stalmach, D. D.; Cox, R. L.

1985-01-01

194

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

195

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

196

Potent Anti-Trypanosoma cruzi Activities of Oxidosqualene Cyclase Inhibitors  

PubMed Central

Trypanosoma cruzi is the protozoan agent that causes Chagas' disease, a major health problem in Latin America. Better drugs are needed to treat infected individuals. The sterol biosynthesis pathway is a potentially excellent target for drug therapy against T. cruzi. In this study, we investigated the antitrypanosomal activities of a series of compounds designed to inhibit a key enzyme in sterol biosynthesis, oxidosqualene cyclase. This enzyme converts 2,3-oxidosqualene to the tetracyclic product, lanosterol. The lead compound, N-(4E,8E)-5,9, 13-trimethyl-4,8, 12-tetradecatrien-1-ylpyridinium, is an electron-poor aromatic mimic of a monocyclized transition state or high-energy intermediate formed from oxidosqualene. This compound and 27 related compounds were tested against mammalian-stage T. cruzi, and 12 inhibited growth by 50% at concentrations below 25 nM. The lead compound was shown to cause an accumulation of oxidosqualene and decreased production of lanosterol and ergosterol, consistent with specific inhibition of the oxidosqualene cyclase. The data demonstrate potent anti-T. cruzi activity associated with inhibition of oxidosqualene cyclase. PMID:11257036

Buckner, Frederick S.; Griffin, John H.; Wilson, Aaron J.; Van Voorhis, Wesley C.

2001-01-01

197

A Potent Lead Induces Apoptosis in Pancreatic Cancer Cells  

PubMed Central

Pancreatic cancer is considered a lethal and treatment-refractory disease. To obtain a potent anticancer drug, the cytotoxic effect of 2-(benzo[d]oxazol-3(2H)-ylmethyl)- 5-((cyclohexylamino)methyl)benzene-1,4-diol, dihydrochloride (NSC48693) on human pancreatic cancer cells CFPAC-1, MiaPaCa-2, and BxPC-3 was assessed in vitro. The proliferation of CFPAC-1, MiaPaCa-2, and BxPC-3 is inhibited with IC50 value of 12.9±0.2, 20.6±0.3, and 6.2±0.6 µM at 48 h, respectively. This discovery is followed with additional analysis to demonstrate that NSC48693 inhibition is due to induction of apoptosis, including Annexin V staining, chromatins staining, and colony forming assays. It is further revealed that NSC48693 induces the release of cytochrome c, reduces mitochondrial membrane potential, generates reactive oxygen species, and activates caspase. These results collectively indicate that NSC48693 mainly induces apoptosis of CFPAC-1, MiaPaCa-2, and BxPC-3 cells by the mitochondrial-mediated apoptotic pathway. Excitingly, the study highlights an encouraging inhibition effect that human embryonic kidney (HEK-293) and liver (HL-7702) cells are more resistant to the antigrowth effect of NSC48693 compared to the three cancer cell lines. From this perspective, NSC48693 should help to open up a new opportunity for the treatment of patients with pancreatic cancer. PMID:22745658

Zhao, Wenjing; Zheng, Xiliang; Wang, Jin; Wang, Erkang

2012-01-01

198

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 ...

199

Effect of contact and non-contact load transfer on the stiffness of two phase materials  

SciTech Connect

Many natural and artificial two-phase materials can be described in the forms of the matrix and inclusions, or the binder and particles. Inclusions/particles are embedded randomly in the matrix/binder. Asphalt concrete (AC), saturated soil and most particle/fiber-reinforced composites fall into this description. For many particulate materials such as AC, the force/load transfer mainly takes paths of particle-particle contacts or particle-binder-particle contacts, and using the contact mechanism to study the behaviors of those materials is appropriate. Descriptively, the contact mechanism can take the forms of concentrated quantities like contact forces, relative approaches, etc. On the other hand, the binder or matrix also has its share on the force/load transfer, and its evolvement should not be over-simplified or ignored. In this article, our study aims at those two-phase particulate materials that when they undergo compression, the force/load transfer in them is primarily through the skeleton of particles in contact. We will employ the basic cell method and attempt to pursue a stiffness study in which the roles of contact and non-contact natures, and the elasticity of binder/matrix are adequately accounted for in constituting the basic cell`s mechanical behavior.

Zhu, H.; Dass, W.C. [Applied Research Assoc. Inc., Tyndall Air Force Base, FL (United States); Rish, J.W. III [Wright Lab., FIVC, Tyndall Air Force Base, FL (United States)

1995-12-31

200

Molecular mechanisms that control endothelial cell contacts.  

PubMed

Endothelial cell contacts control the permeability of the blood vessel wall. This allows the endothelium to form a barrier for solutes, macromolecules, and leukocytes between the vessel lumen and the interstitial space. Loss of this barrier function in pathophysiological situations can lead to extracellular oedema. The ability of leukocytes to enter tissue at sites of inflammation is dependent on molecular mechanisms that allow leukocytes to adhere to the endothelium and to migrate through the endothelial cell layer and the underlying basal lamina. It is a commonly accepted working hypothesis that inter-endothelial cell contacts are actively opened and closed during this process. Angiogenesis is another important process that requires well-controlled regulation of inter-endothelial cell contacts. The formation of new blood vessels by sprouting from pre-existing vessels depends on the loosening of established endothelial cell contacts and the migration of endothelial cells that form the outgrowing sprouts. This review focuses on the molecular composition of endothelial cell surface proteins and proteins of the cytoskeletal undercoat of the plasma membrane at sites of inter-endothelial cell contacts and discusses the current knowledge about the potential role of such molecules in the regulation of endothelial cell contacts. PMID:10685062

Vestweber, D

2000-02-01

201

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

202

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

203

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

204

Copper Oxide Impregnated Textiles with Potent Biocidal Activities  

Microsoft Academic Search

Impregnation or coating of cotton and polyester fibers with cationic copper endows them with potent broad-spectrum antibacterial, antiviral, antifungal, and antimite properties (Borkow, G. and Gabbay, J. (2004). Putting Copper into Action: Copper-impregnated Products with Potent Biocidal Activities, FASEB Jounal, 18(14): 1728-1730). This durable platform technology enables the mass production of woven and non-woven fabrics, such as sheets, pillow covers,

Jeffrey Gabbay; Gadi Borkow; Joseph Mishal; Eli Magen; Richard Zatcoff; Yonat Shemer-Avni

2006-01-01

205

Echistatin is a potent inhibitor of bone resorption in culture  

PubMed Central

The venom protein, s-echistatin, originally derived from the saw-scaled viper Echis carinatus, was found to be a potent inhibitor of bone resorption by isolated osteoclasts. This Arg24-Gly25-Asp26-(RGD)- containing protein inhibited the excavation of bone slices by rat osteoclasts (IC50 = 0.1 nM). It also inhibited the release of [3H]proline from labeled bone particles by chicken osteoclasts (IC50 = 100 nM). By comparison, the tetrapeptide Arg-Gly-Asp-Ser (RGDS) inhibited resorption by rat or chicken osteoclasts with an IC50 of 0.1 mM while ala24-echistatin was inactive. Video microscopy showed that rat osteoclast attachment to substrate was more sensitive to s- echistatin than was the attachment of mononuclear cells or chicken osteoclasts. The difference in sensitivity of rat and chicken osteoclasts to s-echistatin may be due to differences between receptors on rat and chicken osteoclasts for s-echistatin. Antibody localization of echistatin on these cells showed much greater echistatin binding to rat osteoclasts than to chicken osteoclasts. Laser scanning confocal microscopy after immunohistochemical staining showed that s-echistatin binds to osteoclasts, that s-echistatin receptors are most abundant at the osteoclast/glass interface, and that s-echistatin colocalizes with vinculin. Confocal interference reflection microscopy of osteoclasts incubated with s-echistatin, demonstrated colocalization of s- echistatin with the outer edges of clusters of grey contacts at the tips of some lamellipodia. Identification of the echistatin receptor as an integrin was confirmed by colocalization of echistatin fluorescence with staining for an alpha-like subunit. Attachment of bone particles labeled with [3H]proline to chicken osteoclasts confirmed that the mechanism of action of echistatin was to inhibit osteoclast binding to bone presumably by disrupting adhesion structures. These data demonstrate that osteoclasts bind to bone via an RGD-sequence as an obligatory step in bone resorption, that this RGD-binding integrin is at adhesion structures, and that it colocalizes with vinculin and has an alpha-like subunit. PMID:2211834

1990-01-01

206

Enoxacin — a potent inhibitor of theophylline metabolism  

Microsoft Academic Search

The mechanism of the theophylline-enoxacin interaction has been studied in six healthy subjects. Theophylline 250 mg was administered p.o., twice daily for 11 days in a sustained release dosage form. On the 4th day of treatment, blood samples were taken every 2 h and urine was collected over 1 dose interval. From Days 5 to 11 coated tablets of enoxacin

J. Beckmann; W. Elsäßer; U. Gundert-Remy; R. Hertrampf

1987-01-01

207

Exploring the Nature of Contact Freezing  

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

208

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

209

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

210

Media Contact Raymond Mathews  

E-print Network

, they remind us that dreams, hopes and aspirations are the center of art's ability to touch the human spiritMedia Contact Raymond Mathews Lowe Art Museum r.mathews3@umiami.edu 305.284.5422 STEPHEN KNAPP: NEW 24, 2013 at the University of Miami Lowe Art Museum. Stephen Knapp is an American artist best known

Shyu, Mei-Ling

211

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.

212

The Nuclear Contact Exists  

E-print Network

Many-body systems of strongly interacting Fermions are ubiquitous in nature, ranging from High-Tc superconductors and ultra-cold atomic gases to atomic nuclei and neutron stars. Theoretical predictions, recently verified by measurements on ultra-cold atomic gases, show that under certain conditions the universal behavior of systems composed of two kinds of fermions can be described using a single parameter, simply called the contact, which is a measure of the number of different-fermion pairs in close proximity. This paper discusses the relevance of the contact for very different systems: atomic nuclei, made of strongly-interacting neutrons and protons. Here we show that the high-momentum distributions of protons and neutrons in nuclei, dominated by correlated proton-neutron pairs mainly in a spin-triplet state, have the same momentum dependence as those of cold atoms, with a strength described by the contact. We use high-energy electron scattering data to extract a value for the nuclear contact consistent wi...

Hen, O; Piasetzky, E; Miller, G A; Sargsian, M M

2014-01-01

213

[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

214

Technology Advertising Contact Information  

E-print Network

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

Peters, Richard

215

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

216

CONTACT DETAILS International Office  

E-print Network

CONTACT DETAILS International Office Praça Gomes Teixeira s/n 4099-002 Porto - Portugal �ngela the organization of the participants' travel to Porto, we decided to centralize in our office the reservations card for local public transportation in Porto; · Information Kit; · Coffee-breaks; · Social Programme

Hasýrcý, Vasýf

217

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.

Engineering K-Phd Program

218

Entertainment Advertising Contact Information  

E-print Network

, television, music, arts, stage and books, we provide a platform for advertisers to engage with our broad and has a keen interest in film, TV, music and art. A former television and film industry professionalOverview #12;Entertainment Advertising Contact Information Toby Wiseman 02 9282 1865 twiseman

Peters, Richard

219

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

220

Contacting the Government among College Students  

ERIC Educational Resources Information Center

The literature on political participation indicates that initiating contacts with the government is a vital form of civic engagement. Using this criterion to define participation, some researchers claim that students in general are apathetic about government and have poor efficacy about public affairs. The present study examines this assumption by…

Yaghi, Abdulfattah

2009-01-01

221

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

222

Contact Graph Routing  

NASA Technical Reports Server (NTRS)

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

Burleigh, Scott C.

2011-01-01

223

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

ERIC Educational Resources Information Center

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

Crisp, Richard J.; Turner, Rhiannon N.

2009-01-01

224

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

225

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

226

Environmental airborne contact dermatoses.  

PubMed

Abstract 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

227

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

228

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

229

Promoter Activation by CII, a Potent Transcriptional Activator from Bacteriophage 186.  

PubMed

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

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

2014-11-14

230

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

231

Dimeric 2G12 as a Potent Protection against HIV-1  

PubMed Central

We previously showed that broadly neutralizing anti-HIV-1 antibody 2G12 (human IgG1) naturally forms dimers that are more potent than monomeric 2G12 in in vitro neutralization of various strains of HIV-1. In this study, we have investigated the protective effects of monomeric versus dimeric 2G12 against HIV-1 infection in vivo using a humanized mouse model. Our results showed that passively transferred, purified 2G12 dimer is more potent than 2G12 monomer at preventing CD4 T cell loss and suppressing the increase of viral load following HIV-1 infection of humanized mice. Using humanized mice bearing IgG “backpack” tumors that provided 2G12 antibodies continuously, we found that a sustained dimer concentration of 5–25 µg/ml during the course of infection provides effective protection against HIV-1. Importantly, 2G12 dimer at this concentration does not favor mutations of the HIV-1 envelope that would cause the virus to completely escape 2G12 neutralization. We have therefore identified dimeric 2G12 as a potent prophylactic reagent against HIV-1 in vivo, which could be used as part of an antibody cocktail to prevent HIV-1 infection. PMID:21187894

Luo, Xin M.; Lei, Margarida Y. Y.; Feidi, Rana A.; West, Anthony P.; Balazs, Alejandro Benjamin; Bjorkman, Pamela J.; Yang, Lili; Baltimore, David

2010-01-01

232

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): Known Dangerous Allergies (please list): (e.g. medicine, food, plant, animal, insect toxin): #12

Rothman, Daniel

233

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

234

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

235

Contact mechanics of rough surfaces in tribology: multiple asperity contact  

Microsoft Academic Search

Contact modeling of two rough surfaces under normal approach and with relative motion is carried out to predict real area\\u000a of contact and surface and subsurface stresses affecting friction and wear of an interface. When two macroscopically flat\\u000a bodies with microroughness come in contact, the contact occurs at multiple asperities of arbitrary shapes, and varying sizes\\u000a and heights. Deformation at

Bharat Bhushan

1998-01-01

236

It's the thought that counts: content vs. contact  

Microsoft Academic Search

We are currently exploring two domains where the introduction of content gathering technologies is having a negative impact on social contact, particularly telecare technologies on independent living and sensor technologies on remote regional workers. To minimise the incidental cost of such interventions we are investigating enhanced design options that include contact, in the form of presence\\/awareness, as secondary functionality of

Ahmad Hanif Ahmad Baharin; Ralf Mühlberger

2008-01-01

237

Things to Know about Cosmetic Contacts  

MedlinePLUS

... they decided to reclassify cosmetic lenses as cosmetics. Contacts are not Cosmetics Classifying cosmetic contact lenses in ... and soaking solutions. Things to Know About Cosmetic Contacts Things to Know About Cosmetic Contacts— Continued Contact ...

238

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,

239

Metal Silicides: Active elements of ULSI contacts  

NASA Astrophysics Data System (ADS)

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

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

1996-11-01

240

SDS/forms/student info STUDENT CONTACT INFORMATION  

E-print Network

: __________________________________________________________________ Residence Address: _______________________________________________________________ Cell Phone: _________________________________________________________________ _________________________________________________________________ _________________________________________________________________ Home Phone Number: _____________________________________________________ Cell Phone Number: _____________________________ Home Phone: ________________________ Email

Massachusetts at Lowell, University of

241

GO FISH! and Aquatic Ecology Registration Form Contact Information  

E-print Network

Deposit Amount ________ Emergency Information and permission to attend Are there medical conditions, asthma, ADHD)? If yes, please explain_________________________________________________________ Emergency

Dyer, Rodney J.

242

Atrium Space or Banner Request Form Contact Person  

E-print Network

in the building. 8. Helium Balloons are not permitted as it triggers the fire alarm when loose. Other balloons without Helium are fine. Failure to adhere to these conditions will result in denial for this group

Wu, Shin-Tson

243

Plasticity in fretting contact  

NASA Astrophysics Data System (ADS)

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 strains in the substrate as a function of loading and friction coefficient. Shakedown maps and cyclic plastic strain behavior maps are created to describe the relative contribution of cyclic plasticity, ratcheting and shakedown as a function of loading. Cyclic plastic strain amplitudes are presented as a function of tangential load amplitude for various levels of normal pressure and friction using extensive finite element computations. Several plasticity models are considered: elastic/perfectly-plastic, isotropic strain hardening and kinematic strain hardening. The results indicate that, while the plastic strain amplitudes decrease with increased strain hardening, the qualitative behavior is insensitive to the choice of plasticity model. The results are compared with corresponding fully elastic analyses to highlight the role of plasticity during contact deformation and to evaluate the implications of using fully elastic analyses to predict crack nucleation.

Ambrico, J. M.; Begley, M. R.

2000-11-01

244

Ohmic contacts for laser diodes  

NASA Technical Reports Server (NTRS)

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

Ladany, I.; Marinelli, D. P.

1983-01-01

245

Microparticle assembly and contact line dynamics  

NASA Astrophysics Data System (ADS)

This thesis addresses three topics. First, microparticle assembly on solid surfaces from an evaporative suspension is studied. It is well known that microparticles collect near three phase contact lines owing to evaporative fluxes. In a dip coating configuration, if the evaporative flux and plate withdrawal velocity U are matched, large colloidal crystals form. Here, I investigate the consequences of varying the plate withdrawal rate, and find that periodic striped patterns emerge which depend strongly on U. The stripes form when three phase contact lines "jump", or recede rapidly, upon detaching from well-wet particle aggregates on less wet substrates. Stripe width, spacing and height change abruptly at a transition velocity which can be related to a Landau-Levich transition in the flow. The second part of my thesis is a numerical simulation of drop spreading and retraction as a function of drop scale. The drop moves over a thin liquid film, and drop motion is initiated by an impulsive change in surface wettability. Owing to the presence of the film, these simulations require no closure condition at the 'apparent' contact line. Rather, relationships emerge between the contact line velocity and the dynamic contact angle. For nanoscopic drops, molecular effects dominate the drop motion. For drops an order of magnitude larger than the thin film, regimes emerge in which drops move according to Tanner's law, a relationship derived for macroscopic drops. Drop retraction is considerably more rapid than spreading owing to rapid dewetting events near the contact line. This thesis concludes with a discussion of a technique for creating multifunctional surfaces presenting discrete patches of several proteins. The technique relies on microcontact printing (microCP) to define active regions, and the use of a microfluidics device to deliver proteins to those regions. The surfaces are used to capture cells from a suspension, to sort cells from a mixed suspension, and to study the shear-dependent cell adhesion. Potential applications include biosensors, fundamental studies of cell adhesion, and of stem cell differentiation.

Ghosh, Moniraj

246

Medicare: Helpful Contacts  

MedlinePLUS

... fast appeal Your Medicare rights Authorization to Disclose Personal Health Information Manage Your Health Login to MyMedicare.gov Get Medicare forms Advance directives & long-term care Electronic prescribing Electronic Health Records (EHRs) Medicare's Blue Button Coordinating your care Forms, ...

247

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

Microsoft Academic Search

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

Martin H. Teicher; Gordana D. Vitaliano

2011-01-01

248

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

249

Potent pyrrolidine- and piperidine-based BACE-1 inhibitors  

SciTech Connect

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

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

2008-08-18

250

RESEARCH PAPER AF-353, a novel, potent and orally bioavailable  

E-print Network

RESEARCH PAPER AF-353, a novel, potent and orally bioavailable P2X3/P2X2/3 receptor antagonistbph; FLIPR, fluorometric imaging plate reader; HPLC, high performance liquid chromatography; IBS, irritable bowel syndrome; LC-MS/MS, liquid chromatography-mass spectrometry; P2X3-KO, P2X3 receptor knockout

Burnstock, Geoffrey

251

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

252

Reboxetine: a pharmacologically potent, selective, and specific norepinephrine reuptake inhibitor  

Microsoft Academic Search

Background: Reboxetine is a potent antidepressant, with efficacy comparable to that of imipramine, desipramine, and fluoxetine, and has improved side-effect profile. The basis of its efficacy and improved tolerability is sought through studies of reboxetine in a number of pharmacological models of depression.Methods: Pharmacological selectivity for uptake systems was defined by uptake and binding assays for the three monoamine uptake

Erik H. F. Wong; Mark S. Sonders; Susan G. Amara; Paula M. Tinholt; Montford F. P. Piercey; William P. Hoffmann; Deborah K. Hyslop; Stanley Franklin; Roger D. Porsolt; Alberto Bonsignori; Nicola Carfagna; Robert A. McArthur

2000-01-01

253

Factor VIII/von Willebrand factor has potent lectin activity.  

PubMed

Highly-purified plasma and platelet Factor VIII/von Willebrand Factor had potent lectin activity when measured in a haemagglutination assay. This lectin activity was inhibited by monoclonal and heterologous antibodies to Factor VIII/von Willebrand Factor as well as by hexosamines, mannose and net-positively charged amino acids. PMID:6422929

Booth, W J; Furby, F H; Berndt, M C; Castaldi, P A

1984-01-30

254

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

255

Peptidomimetic inhibitors of protein farnesyltransferase show potent antimalarial activity  

Microsoft Academic Search

Malaria continues to represent a very serious health problem in the tropics. The current methods of clinical treatment are showing deficiencies due to the increased incidence of resistance in the parasite. In the present paper we report the design, synthesis, and evaluation of potential antimalarial agents against a novel target, protein farnesyltransferase. We show that the most potent compounds are

Junko Ohkanda; Jeffrey W. Lockman; Kohei Yokoyama; Michael H. Gelb; Simon L. Croft; Howard Kendrick; Maria Isabel Harrell; Jean E. Feagin; Michelle A. Blaskovich; Said M. Sebti; Andrew D. Hamilton

2001-01-01

256

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

257

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

258

Equilibrium contact angle or the most-stable contact angle?  

PubMed

It is well-established that the equilibrium contact angle in a thermodynamic framework is an "unattainable" contact angle. Instead, the most-stable contact angle obtained from mechanical stimuli of the system is indeed experimentally accessible. Monitoring the susceptibility of a sessile drop to a mechanical stimulus enables to identify the most stable drop configuration within the practical range of contact angle hysteresis. Two different stimuli may be used with sessile drops: mechanical vibration and tilting. The most stable drop against vibration should reveal the changeless contact angle but against the gravity force, it should reveal the highest resistance to slide down. After the corresponding mechanical stimulus, once the excited drop configuration is examined, the focus will be on the contact angle of the initial drop configuration. This methodology needs to map significantly the static drop configurations with different stable contact angles. The most-stable contact angle, together with the advancing and receding contact angles, completes the description of physically realizable configurations of a solid-liquid system. Since the most-stable contact angle is energetically significant, it may be used in the Wenzel, Cassie or Cassie-Baxter equations accordingly or for the surface energy evaluation. PMID:24140073

Montes Ruiz-Cabello, F J; Rodríguez-Valverde, M A; Cabrerizo-Vílchez, M A

2014-04-01

259

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

260

Modeling intermittent contact for flexible multibody systems  

Microsoft Academic Search

This paper consists of two parts. The first part presents a complementarity based recursive scheme to model intermittent contact\\u000a for flexible multibody systems. A recursive divide-and-conquer framework is used to explicitly impose the bilateral constraints\\u000a in the entire system. The presented approach is an extension of the hybrid scheme for rigid multibody systems to allow for\\u000a small deformations in form

Kishor D. Bhalerao; Kurt S. Anderson

2010-01-01

261

Characterisation of UBP296: a novel, potent and selective kainate receptor antagonist.  

PubMed

Willardiine derivatives with an N3-benzyl substituent bearing an acidic group have been synthesized with the aim of producing selective antagonists for GLUK5-containing kainate receptors. UBP296 was found to be a potent and selective antagonist of native GLUK5-containing kainate receptors in the spinal cord, with activity residing in the S enantiomer (UBP302). In cells expressing human kainate receptor subunits, UBP296 selectively depressed glutamate-induced calcium influx in cells containing GLUK5 in homomeric or heteromeric forms. In radioligand displacement binding studies, the willardiine analogues displaced [3H]kainate binding with IC50 values >100 microM at rat GLUK6, GLUK2 or GLUK6/GLUK2. An explanation of the GLUK5 selectivity of UBP296 was obtained using homology models of the antagonist bound forms of GLUK5 and GLUK6. In rat hippocampal slices, UBP296 reversibly blocked ATPA-induced depressions of synaptic transmission at concentrations subthreshold for affecting AMPA receptor-mediated synaptic transmission directly. UBP296 also completely blocked the induction of mossy fibre LTP, in medium containing 2 mM (but not 4 mM) Ca2+. These data provide further evidence for a role for GLUK5-containing kainate receptors in mossy fibre LTP. In conclusion, UBP296 is the most potent and selective antagonist of GLUK5-containing kainate receptors so far described. PMID:15165833

More, Julia C A; Nistico, Robert; Dolman, Nigel P; Clarke, Vernon R J; Alt, Andrew J; Ogden, Ann M; Buelens, Floris P; Troop, Helen M; Kelland, Eve E; Pilato, Fabio; Bleakman, David; Bortolotto, Zuner A; Collingridge, Graham L; Jane, David E

2004-07-01

262

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

263

Incident Report Form [yellow form  

E-print Network

Description of Incident: Action Taken by DRS Employee: Time University Police were called: Officer responding to call: Badge # of Officer: Case #: Time University Police Arrived: Were University Police contacted

Amin, S. Massoud

264

Graphite-Graphene Contact Resistance  

NASA Astrophysics Data System (ADS)

Exploiting the exceptional electronic properties of graphene has been attempted in several applications. However, graphene based applications still lag behind conventional electronics due, in part, to the highly resistive metal-graphene junction. For example, graphene based RF transistors suffer a diminished (fmax) due to highly resistive source-drain contacts (>200 ?- ?m). Reducing this paracistic resistance can yield substantial improvement in device performance for transistors and many other applications. To achieve this, we create an electrical contact to graphene using mesoscopic, exfoliated graphite (10 - 20 nm thick). We fabricate graphite-graphene contacts by transferring pre-defined graphite contacts to graphene on silicon dioxide. Experimental measurement has shown the contact resistance to be <50 ?- ?m, a four-fold improvement over conventional contacts to graphene.

Chari, Tarun; Dean, Cory; Meric, Inanc; Wang, Lei; Shepard, Ken

2013-03-01

265

PROSPR Contact Information  

Cancer.gov

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

266

Media Information Your contact  

E-print Network

forward because, for example, the unwanted side effects of drugs could be avoided. In the current issue harmless and causes damage: for example, while one form of penicillamine is effective against arthritis, which now has five positive charges, explodes due to the high repulsion between the positively charged

Reggelin, Michael

267

Media Contact Raymond Mathews  

E-print Network

, 2013) ­ Beauty Beyond Nature presents more than 70 of Paul Stankard's intricately flame-worked still experimentation, Stankard implemented a technique he calls "cloistering" where he laminates a layer of colored weaves together color and form into complex arrangements, setting up his elements in grids that intensify

Shyu, Mei-Ling

268

Applied Research Contact Information  

Cancer.gov

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

269

Indolocarbazoles: potent, selective inhibitors of human cytomegalovirus replication  

Microsoft Academic Search

In our search for new, safer anti-HCMV agents, we discovered that the natural product Arcyriaflavin A (1a) was a potent inhibitor of HCMV replication in cell culture. A series of analogues (symmetrical indolocarbazoles) was synthesised to investigate structure–activity relationships in this series against a range of herpes viruses (HCMV, VZV, HSV1, and 2). This identified a number of novel, selective

Martin J. Slater; Stuart Cockerill; Robert Baxter; Robert W. Bonser; Kam Gohil; Clare Gowrie; J. Edward Robinson; Edward Littler; Nigel Parry; Roger Randall; Wendy Snowden

1999-01-01

270

RFI641, a Potent Respiratory Syncytial Virus Inhibitor  

Microsoft Academic Search

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

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

2002-01-01

271

Total synthesis of valerenic acid, a potent GABAA receptor modulator.  

PubMed

The first total synthesis of the sesquiterpenoid valerenic acid, a constituent of Valeriana officinalis, is described. The compound is a potent modulator of the GABA(A) receptor and may thus be useful in the treatment of various dysfunctions of the central nervous system. The synthesis is enantio-, diastereo-, and regiocontrolled and utilizes an enyne-RCM, a metal-coordinated Diels-Alder reaction, a hydroxy-directed Crabtree hydrogenation, and a Negishi methylation as key steps. PMID:19178294

Ramharter, Jürgen; Mulzer, Johann

2009-03-01

272

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

273

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

274

Peptidomimetic inhibitors of protein farnesyltransferase show potent antimalarial activity.  

PubMed

Malaria continues to represent a very serious health problem in the tropics. The current methods of clinical treatment are showing deficiencies due to the increased incidence of resistance in the parasite. In the present paper we report the design, synthesis, and evaluation of potential antimalarial agents against a novel target, protein farnesyltransferase. We show that the most potent compounds are active against Plasmodium falciparum in vitro at submicromolar concentrations. PMID:11277514

Ohkanda, J; Lockman, J W; Yokoyama, K; Gelb, M H; Croft, S L; Kendrick, H; Harrell, M I; Feagin, J E; Blaskovich, M A; Sebti, S M; Hamilton, A D

2001-03-26

275

Daidzin: a potent, selective inhibitor of human mitochondrial aldehyde dehydrogenase.  

PubMed Central

Human mitochondrial aldehyde dehydrogenase (ALDH-I) is potently, reversibly, and selectively inhibited by an isoflavone isolated from Radix puerariae and identified as daidzin, the 7-glucoside of 4',7-dihydroxyisoflavone. Kinetic analysis with formaldehyde as substrate reveals that daidzin inhibits ALDH-I competitively with respect to formaldehyde with a Ki of 40 nM, and uncompetitively with respect to the coenzyme NAD+. The human cytosolic aldehyde dehydrogenase isozyme (ALDH-II) is nearly 3 orders of magnitude less sensitive to daidzin inhibition. Daidzin does not inhibit human class I, II, or III alcohol dehydrogenases, nor does it have any significant effect on biological systems that are known to be affected by other isoflavones. Among more than 40 structurally related compounds surveyed, 12 inhibit ALDH-I, but only prunetin and 5-hydroxydaidzin (genistin) combine high selectivity and potency, although they are 7- to 15-fold less potent than daidzin. Structure-function relationships have established a basis for the design and synthesis of additional ALDH inhibitors that could both be yet more potent and specific. PMID:8433985

Keung, W M; Vallee, B L

1993-01-01

276

Potent thermogenic action of triiodothyroacetic acid in brown adipocytes.  

PubMed

Triiodothyroacetic acid (TRIAC) is a triiodothyronine (T3) metabolite with high affinity for T3 nuclear receptors. We compared the thermogenic action of TRIAC versus T3 in brown adipocytes, by studying target genes known to mediate thermogenic action: uncoupling protein 1 (UCP-1), a marker of brown adipocytes, and type II-5'deiodinase (D2), which provides the T3 required for thermogenesis. TRIAC is 10-50 times more potent than T3 at increasing the adrenergic induction of UCP-1 mRNA and D2 activities. TRIAC action on UCP-1 is exerted at the transcriptional level. In the presence of an adrenergic stimulus, TRIAC is also more potent than T3, inducing lipoprotein lipase mRNA and 5 deiodinase (D3) activity and mRNA. Maximal effects occur at very low concentrations (0.2 nM). The greater potency of TRIAC is not due to preferential cellular or nuclear uptake. Therefore, TRIAC is a potent thermogenic agent that might increase energy expenditure and regulate T3 production in brown adipocytes. PMID:14523556

Medina-Gomez, G; Hernàndez, A; Calvo, R-M; Martin, E; Obregón, M-J

2003-09-01

277

Broad neutralization coverage of HIV by multiple highly potent antibodies  

PubMed Central

Broadly neutralizing antibodies (bnAbs) against highly variable viral pathogens are much sought-after to treat or protect against global circulating viruses. We have probed the neutralizing antibody repertoires of four HIV-infected donors with remarkably broad and potent neutralizing responses and rescued 17 new monoclonal antibodies (MAbs) that neutralize broadly across clades. Many of the new MAbs are almost 10-fold more potent than the recently described PG9, PG16, and VRC01 bnMAbs and 100-fold more potent than the original prototype HIV bnMAbs1–3. The MAbs largely recapitulate the neutralization breadth found in the corresponding donor serum and many recognize novel epitopes on envelope (Env) glycoprotein gp120, illuminating new targets for vaccine design. Analysis of neutralization by the full complement of anti-HIV bnMAbs now available reveals that certain combinations of antibodies provide significantly more favorable coverage of the enormous diversity of global circulating viruses than others and these combinations might be sought in active or passive immunization regimes. Overall, the isolation of multiple HIV bnMAbs, from several donors, that, in aggregate, provide broad coverage at low concentrations is a highly positive indicator for the eventual design of an effective antibody-based HIV vaccine. PMID:21849977

Walker, Laura M.; Huber, Michael; Doores, Katie J.; Falkowska, Emilia; Pejchal, Robert; Julien, Jean-Philippe; Wang, Sheng-Kai; Ramos, Alejandra; Chan-Hui, Po-Ying; Moyle, Matthew; Mitcham, Jennifer L.; Hammond, Phillip W.; Olsen, Ole A.; Phung, Pham; Fling, Steven; Wong, Chi-Huey; Phogat, Sanjay; Wrin, Terri; Simek, Melissa D.; Koff, Wayne C.; Wilson, Ian A.; Burton, Dennis R.; Poignard, Pascal

2012-01-01

278

Policy on Media Contacts Regarding Athletes Policy on Media Contacts  

E-print Network

's intercollegiate athletics program to the public, including but not limited to all websites, social media accounts Office/Department: Athletics Keywords: athletics, social media, publicity, interview, student-athlete #12Policy on Media Contacts Regarding Athletes 9/1/2013 Policy on Media Contacts Regarding Athletics I

Sridhar, Srinivas

279

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

280

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

PubMed Central

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

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

2012-01-01

281

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

282

Healthy Contact Lens Wear and Care  

MedlinePLUS Videos and Cool Tools

... Infections Eye infections related to contact lens wear... Water & Contact Lenses Keep contact lenses away from all ... Keratitis Parasitic/Amebic Keratitis Viral Keratitis Other Complications Water & Contact Lenses Publications, Data, & Statistics Health Promotion Materials ...

283

Predictive models for moving contact line flows  

NASA Technical Reports Server (NTRS)

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

Rame, Enrique; Garoff, Stephen

2003-01-01

284

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:

285

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

286

Contact dermatitis with henna tattoo.  

PubMed

Allergic and irritant reactions to henna are rare. Para-phenylenediamine, which is sometimes added to obtain a dark, blackish henna, causes the majority of contact dermatitis reported related with tattoos. Allergic contact dermatitis due to temporary paint-on tattoo with black henna is described in two adolescents. PMID:19478355

Uzuner, Nevin; Olmez, Duygu; Babayigit, Arzu; Vayvada, Ozlem

2009-05-01

287

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...

288

Joule heat in point contacts  

Microsoft Academic Search

We considered Joule heat in point contacts which are the elementary building blocks of ballistic devices with nonlocal transport based on two dimensional electron gas. We present a theory of a point contact up to second order in the applied voltage. Out of our calculation arises the main difference in Joule heat delivery between local and nonlocal transport. While for

Michal Rokni; Y. Levinson

1995-01-01

289

Contact sensitization in the elderly.  

PubMed

Contact dermatitis from irritant and allergic sources is the reason for 6% to 10% of all dermatologic visits with considerable morbidity and economic impact. Allergic contact dermatitis is a T-cell-mediated inflammatory reaction and develops in predisposed individuals as a consequence of environmental exposure to allergens. Aging is correlated with the rate and type of contact sensitization because of "immunosenescence." The number of old people is growing around the world. This contribution reviews the main findings from published epidemiologic studies on contact allergy in elderly populations. In all examined studies, patch testing was performed in patients with cutaneous manifestations possibly related to contact dermatitis; the prevalence of contact dermatitis in the elderly was from 33% to 64%. Establishing the most frequent allergens responsible for allergic contact dermatitis in the elderly is a hard task. The commonest allergens reported were nickel sulfate, fragrance mix, diamino diphenylmethane, lanolin alcohols, paraben mix, Euxyl K400, quinoline mix, and balsam of Peru. We emphasize that allergens surveillance is needed to realize an "elderly series" for having a useful adjunct to contact allergy that may help the treatment of each patient. PMID:21146728

Balato, Anna; Balato, Nicola; Di Costanzo, Luisa; Ayala, Fabio

2011-01-01

290

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

291

Nodal sets and contact structures  

NASA Astrophysics Data System (ADS)

In this thesis the author develops techniques to study contact structures via Riemannian geometry. The main observation is a relation between characteristic surfaces of contact structures and zero sets of solutions to certain subelliptic PDEs. This relation makes it possible to derive, under a symmetry assumption, necessary and sufficient conditions for tightness of contact structures arising from a certain class of invariant curl eigenfields. Further, it has implications in the energy relaxation of this special class of fluid flows. Specifically, the author shows existence of an energy minimizing curl eigenfield which is orthogonal to an overtwisted contact structure. It provides a counterexample to the conjecture of Etnyre and Ghrist posed in their work on hydrodynamics of contact structures.

Komendarczyk, Rafal

292

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

293

Effects of arsenic n+ contact implants on memory switching in vertical polycrystalline silicon resistors  

Microsoft Academic Search

The effects of arsenic implants, which form the lower and the upper n+ contact regions of the vertical polycrystalline silicon resistor, on memory switching have been investigated. It is shown that switching in devices without the lower n+ contact is initiated due to Joule heating, whereas in devices without the upper n+ contact, it is electronic in nature. These resistors

V. Malhotra

1992-01-01

294

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

295

'Contact' in Space Leads to New Lenses  

NASA Technical Reports Server (NTRS)

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

2004-01-01

296

Modelling receding contact lines on superhydrophobic surfaces  

E-print Network

We use mesoscale simulations to study the depinning of a receding contact line on a superhydrophobic surface patterned by a regular array of posts. In order that the simulations are feasible, we introduce a novel geometry where a column of liquid dewets a capillary bounded by a superhydrophobic plane which faces a smooth hydrophilic wall of variable contact angle. We present results for the dependence of the depinning angle on the shape and spacing of the posts, and discuss the form of the meniscus at depinning. We find, in agreement with [17], that the local post concentration is a primary factor in controlling the depinning angle, and show that the numerical results agree well with recent experiments. We also present two examples of metastable pinned configurations where the posts are partially wet.

B. M. Mognetti; J. M. Yeomans

2010-09-23

297

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

E-print Network

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

Pantaleone, Jim

298

Temperature effects on adhesive wear in dry sliding contacts  

Microsoft Academic Search

In many metal forming operations, frictional heating occurs at the interface due to a sliding contact. Generally, the controlling wear mechanism in the tribological system is attributed to adhesive wear. Understanding of the influence of temperature on wear mechanisms is needed for the development of materials and for optimization of the forming process. Dry sliding tests were conducted at different

A. Gåård; N. Hallbäck; P. Krakhmalev; J. Bergström

2010-01-01

299

Mevinolin: A Highly Potent Competitive Inhibitor of Hydroxymethylglutaryl-Coenzyme A Reductase and a Cholesterol-Lowering Agent  

Microsoft Academic Search

Mevinolin, a fungal metabolite, was isolated from cultures of Aspergillus terreus. The structure and absolute configuration of mevinolin and its open acid form, mevinolinic acid, were determined by a combination of physical techniques. Mevinolin was shown to be 1,2,6,7,8,8a-hexahydro-beta , delta -dihydroxy-2,6-dimethyl-8-(2-methyl-1-oxobutoxy)-1-naphthaleneheptanoic acid delta -lactone. Mevinolin in the hydroxy acid form, mevinolinic acid, is a potent competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme

A. W. Alberts; J. Chen; G. Kuron; V. Hunt; J. Huff; C. Hoffman; J. Rothrock; M. Lopez; H. Joshua; E. Harris; A. Patchett; R. Monaghan; S. Currie; E. Stapley; G. Albers-Schonberg; O. Hensens; J. Hirshfield; K. Hoogsteen; J. Liesch; J. Springer

1980-01-01

300

Applying a multitarget rational drug design strategy: the first set of modulators with potent and balanced activity toward dopamine D3 receptor and fatty acid amide hydrolase.  

PubMed

Combining computer-assisted drug design and synthetic efforts, we generated compounds with potent and balanced activities toward both D3 dopamine receptor and fatty acid amide hydrolase (FAAH) enzyme. By concurrently modulating these targets, our compounds hold great potential toward exerting a disease-modifying effect on nicotine addiction and other forms of compulsive behavior. PMID:24691497

De Simone, Alessio; Ruda, Gian Filippo; Albani, Clara; Tarozzo, Glauco; Bandiera, Tiziano; Piomelli, Daniele; Cavalli, Andrea; Bottegoni, Giovanni

2014-05-18

301

Design of potent substrate-analogue inhibitors of canine renin  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

302

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

303

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-8700/97/0610-00 CONTENTS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

304

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

305

Discovery of a highly potent series of TLR7 agonists.  

PubMed

The discovery of a series of highly potent and novel TLR7 agonist interferon inducers is described. Structure-activity relationships are presented, along with pharmacokinetic studies of a lead molecule from this series of N9-pyridylmethyl-8-oxo-3-deazapurine analogues. A rationale for the very high potency observed is offered. An investigation of the clearance mechanism of this class of compounds in rat was carried out, resulting in aldehyde oxidase mediated oxidation being identified as a key component of the high clearance observed. A possible solution to this problem is discussed. PMID:21885277

Jones, Peter; Pryde, David C; Tran, Thien-Duc; Adam, Fiona M; Bish, Gerwyn; Calo, Frederick; Ciaramella, Guiseppe; Dixon, Rachel; Duckworth, Jonathan; Fox, David N A; Hay, Duncan A; Hitchin, James; Horscroft, Nigel; Howard, Martin; Laxton, Carl; Parkinson, Tanya; Parsons, Gemma; Proctor, Katie; Smith, Mya C; Smith, Nicholas; Thomas, Amy

2011-10-01

306

Discovery of potent and specific CXCR3 antagonists.  

PubMed

The optimization of a series of 8-aza-quinazolinone analogs for antagonist activity against the CXCR3 receptor is reported. Compounds were optimized to avoid the formation of active metabolites and time-dependent-inhibitors of CYP3A4. In addition, antagonists showed potent against CXCR3 activity in whole blood and optimized to avoid activity in the chromosomal aberration assay. Compound 25 was identified as having the optimal balance of CXCR3 activity and pharmacokinetic properties across multiple pre-clinical species, which are reported herein. PMID:22130135

Chen, Xiaoqi; Mihalic, Jeff; Deignan, Jeff; Gustin, Darin J; Duquette, Jason; Du, Xiaohui; Chan, Johann; Fu, Zice; Johnson, Michael; Li, An-Rong; Henne, Kirk; Sullivan, Tim; Lemon, Bryan; Ma, Ji; Miao, Shichang; Tonn, George; Collins, Tassie; Medina, Julio C

2012-01-01

307

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

308

Discovery of Tertiary Sulfonamides as Potent Liver X Receptor Antagonists  

SciTech Connect

Tertiary sulfonamides were identified in a HTS as dual liver X receptor (LXR, NR1H2, and NR1H3) ligands, and the binding affinity of the series was increased through iterative analogue synthesis. A ligand-bound cocrystal structure was determined which elucidated key interactions for high binding affinity. Further characterization of the tertiary sulfonamide series led to the identification of high affinity LXR antagonists. GSK2033 (17) is the first potent cell-active LXR antagonist described to date. 17 may be a useful chemical probe to explore the cell biology of this orphan nuclear receptor.

Zuercher, William J.; Buckholz† , Richard G.; Campobasso, Nino; Collins, Jon L.; Galardi, Cristin M.; Gampe, Robert T.; Hyatt, Stephen M.; Merrihew, Susan L.; Moore, John T.; Oplinger, Jeffrey A.; Reid, Paul R.; Spearing, Paul K.; Stanley, Thomas B.; Stewart, Eugene L.; Willson, Timothy M. (GSKNC)

2010-08-12

309

Trigocherrierin A, a potent inhibitor of chikungunya virus replication.  

PubMed

Trigocherrierin A (1) and trigocherriolide E (2), two new daphnane diterpenoid orthoesters (DDOs), and six chlorinated analogues, trigocherrins A, B, F and trigocherriolides A-C, were isolated from the leaves of Trigonostemon cherrieri. Their structures were identified by mass spectrometry, extensive one- and two-dimensional NMR spectroscopy and through comparison with data reported in the literature. These compounds are potent and selective inhibitors of chikungunya virus (CHIKV) replication. Among the DDOs isolated, compound 1 exhibited the strongest anti-CHIKV activity (EC?? = 0.6 ± 0.1 µM, SI = 71.7). PMID:24662077

Bourjot, Mélanie; Leyssen, Pieter; Neyts, Johan; Dumontet, Vincent; Litaudon, Marc

2014-01-01

310

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

PubMed

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

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

2008-10-01

311

16 CFR 1500.133 - Extremely flammable contact adhesives; labeling.  

...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

312

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

313

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

314

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

315

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

316

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

317

Plasma contacting - An enabling technology  

NASA Technical Reports Server (NTRS)

An experimental study of plasma contacting with an emphasis on the electron collection mode of this process is described. Results illustrating variations in plasma property profiles and potential differences that develop at hollow cathode plasma contactors are presented. A model of the electron collection plasma contacting process that is consistent with experimentally measured results is reviewed. The shortcomings of laboratory results as direct predictors of contactor performance in space and their usefulness in validating numerical models of the contacting process, that can be used to predict such performance, are discussed.

Williams, John D.; Wilbur, Paul J.

1989-01-01

318

Higher Dimensional Theory of Contact Resistance and Experimental Validation  

NASA Astrophysics Data System (ADS)

Electrical contact is an important issue to Z-pinches, pulsed power systems, field emitters, and wafer evaluation, etc. Because of the surface roughness on a microscopic scale, true contact between two pieces of metal occurs only on the asperities of the two contacting surfaces, resulting in contact resistance [1]. We recently developed a higher dimensional theory of contact resistance for an asperity of transverse dimension (a) and finite axial length (h) connecting two metal blocks [2]. For asperity of rectangular, cylindrical or funnel shape, the contact resistance is found to be of the form R[1+p(h/a)] where R is the corresponding h=0 ``a-spot'' theory limit of Holm and Timsit [1], p has a simple form which is geometry-dependent. This scaling law is verified against electrostatic code results [2]. It is also recently validated in a series of controlled experiments [3]. This work is supported by Sandia, AFOSR, AFRL, L-3, and Northrop-Grumman. [4pt] [1] R. Holm, Electric Contact (Springer-Verlag, 1967); R. S. Timsit, IEEE Trans. Components Packaging Tech. 22, 85 (1999). [0pt] [2] Y. Y. Lau and W. Tang, J. Appl. Phys. 105, 124902 (2009). [0pt] [3] M. R. Gomez et al., Appl. Phys. Lett. (submitted).

Tang, W.; Gomez, M.; French, D.; Zier, J.; Zhang, P.; Lau, Y. Y.; Gilgenbach, R.

2009-11-01

319

Monomolecular silane films on glass surfaces—contact angle measurements  

Microsoft Academic Search

Contact angle measurements have been done for silanized glass plates with 11 different coatings. For a monomolecular film of tridecafluoro-1,1,2,2-tetrahydrooctyl-1-triethoxysilyl groups on a glass surface, contact angles (water 24°C) have been measured to ?a = 111°, ?r = 99°. The figures are comparable with those obtained for bulk Teflon, but with smaller hysteresis behaviour. The silanes are believed to form

Christian Erich Zybill; How Ghee Ang; Luo Lan; Wen Ying Choy; Eric Fang Kin Meng

1997-01-01

320

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

321

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

322

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

323

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

324

A Flexible Multibody Pantograph Model for the Analysis of the Catenary–Pantograph Contact  

Microsoft Academic Search

\\u000a The pantograph–catenary system is still the most reliable form of collecting electric energy for running trains. This system\\u000a should ideally run with relatively low contact forces, in order to minimize wear and damage of the contacting elements but\\u000a without contact loss to avoid power supply interruption and electric arching. However, the quality of the pantograph–catenary\\u000a contact may be affected by

Jorge Ambrósio; Frederico Rauter; João Pombo; Manuel S. Pereira

325

Forms & Guidelines  

Cancer.gov

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, Current DCP Letter of Intent Submission Form

326

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

327

Use of contact lenses by firefighters: Part 2. Clinical evaluation.  

PubMed

Contact lenses can be worn in a variety of environmental conditions and do not increase the wearers risk of injury. In many situations they offer significant corneal protection. Currently firefighters are prohibited from using contact lenses. To evaluate whether contact lenses are a safe form of visual correction 50 firefighters were fitted, and examined after 1, 4 and 10 months of contact lens wear. Twenty-nine were fitted with soft contact lenses, and 21 with rigid gas permeable contact lenses. Statistically significant increase in lid sulcus hyperaemia was found in both the SCL and RGPCL groups (P < 0.01, P = 0.02, respectively), as well as an increase in hyperaemia of the vertical quadrant of the bulbar conjunctivae (P = 0.01, P = 0.02, respectively). In addition the RGPCL group showed a statistically significant increase in hyperaemia of the lateral portion of the bulbar conjunctivae (P < 0.01), consistent with exposure epitheliopathy. The SCL group showed statistically significant increase in corneal staining in the vertical quadrant for all visits (P = 0.02, P = 0.01, P = 0.02 for all visits, respectively), indicative of lens dehydration. These findings although clinically significant are not unique to firefighting, and are found within a "normal" population of contact lens wearers. In conjunction with questionnaire data (Owen et all, 1996) we conclude that soft contact lenses can be worn safely by firefighters without additional risk. PMID:9196662

Owen, C G; Margrain, T H; Woodward, E G

1997-05-01

328

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

329

Drug Screen Targeted at Plasmodium Liver Stages Identifies a Potent Multistage Antimalarial Drug  

PubMed Central

Plasmodium parasites undergo a clinically silent and obligatory developmental phase in the host’s liver cells before they are able to infect erythrocytes and cause malaria symptoms. To overcome the scarcity of compounds targeting the liver stage of malaria, we screened a library of 1037 existing drugs for their ability to inhibit Plasmodium hepatic development. Decoquinate emerged as the strongest inhibitor of Plasmodium liver stages, both in vitro and in vivo. Furthermore, decoquinate kills the parasite’s replicative blood stages and is active against developing gametocytes, the forms responsible for transmission. The drug acts by selectively and specifically inhibiting the parasite’s mitochondrial bc1 complex, with little cross-resistance with the antimalarial drug atovaquone. Oral administration of a single dose of decoquinate effectively prevents the appearance of disease, warranting its exploitation as a potent antimalarial compound. PMID:22396598

da Cruz, Filipa P.; Martin, Cecilie; Buchholz, Kathrin; Lafuente-Monasterio, Maria J.; Rodrigues, Tiago; Sonnichsen, Birte; Moreira, Rui; Gamo, Francisco-Javier; Marti, Matthias; Mota, Maria M.; Hannus, Michael

2012-01-01

330

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

331

Racial Disparity in Police Contacts  

PubMed Central

Criminologists agree the race disparity in arrests cannot be fully explained by differences in criminal behavior. We examine social environment factors that may lead to racial differences in police contact in early adolescence, including family, peers, school, and community. Data are from 331 8th-grade students. Blacks were almost twice as likely as Whites to report a police contact. Blacks reported more property crime but not more violent crime than Whites. Police contacts were increased by having a parent who had been arrested, a sibling involved in criminal activity, higher observed reward for negative behavior, having school disciplinary actions, and knowing adults who engaged in substance abuse or criminal behavior. Race differences in police contacts were partially attributable to more school discipline. PMID:24363956

Crutchfield, Robert D.; Haggerty, Kevin P.; McGlynn, Anne; Catalano, Richard F.

2013-01-01

332

Starved elastohydrodynamic lubricated elliptical contacts  

NASA Technical Reports Server (NTRS)

A theoretical study of the influence of lubricant starvation on film thickness and pressure in hard and soft elliptical elastohydrodynamic contacts is presented. From the results for both hard and soft EHL contacts a simple and important dimensionless inlet boundary distance is specified. This inlet boundary defines whether a fully flooded or a starved condition exists in the contact. Furthermore it is found that the film thickness for a starved condition could be written in dimensionless terms as a function of the inlet distance parameter and the film thickness for a fully flooded condition. Contour plots of pressure and film thickness in and around the contact are shown for fully flooded and starved conditions. The theoretical findings are compared directly with results obtained experimentally.

Hamrock, B. J.

1980-01-01

333

NATHAN I. HAMMER CONTACT INFORMATION  

E-print Network

NATHAN I. HAMMER CONTACT INFORMATION Department of Chemistry and Biochemistry Voice: (662) 915 President (2000 � 2001) and President (2001 � 2002) #12;Nathan I. Hammer, University of Mississippi CV - 2

Tchumper, Gregory S.

334

Connector contact-ring bus  

NASA Technical Reports Server (NTRS)

Use of device eliminates crimp connectors and ferrules, resulting in compact termination assembly and efficient use of back-shell space. Pair of insulator rings, one at each end of assembly, provides spacing between disc caps and contact rings.

Ligon, J.

1976-01-01

335

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

336

Contact Measurements on Atomic BEC  

NASA Astrophysics Data System (ADS)

For ultracold fermions, a powerful set of universal relations, centered on a quantity called the contact, connects the strength of short-range two-body correlations to the thermodynamics of a many-body system with zero-range interactions [1]. An interesting question is whether these ideas and the concept of the contact can be extended to bosons, where issues include the decreasing stability of BECs with increasing repulsive interactions and the possibility of three-body interactions. We present measurements of the contact, using RF spectroscopy, for an ^85Rb atomic Bose-Einstein condensate (BEC) near a Feshbach resonance. To connect our measurements of the contact to three-body interactions, we located an Efimov resonance in ^85Rb atoms with loss measurements and thus determine the three-body interaction parameter. [4pt] [1] S. Tan, Ann. Phys. 323, 2971 (2008)[0pt] [2] E. Braaten, D. Kang, and L. Platter, Phys. Rev. Lett. 106, 153005 (2011).

Makotyn, Philip; Klauss, Catherine; Wild, Robert; Cornell, Eric; Jin, Deborah

2012-06-01

337

Potent CYP3A4 inhibitory constituents of Piper cubeba.  

PubMed

The EtOAc-soluble fraction of the water extract of Piper cubeba, having shown potent inhibitory activity on the metabolism mediated by CYP3A4, was subjected to activity-guided isolation to yield two new lignans, (8R,8'R)-4-hydroxycubebinone (1) and (8R,8'R,9'S)-5-methoxyclusin (2), and two new sesquiterpenes, (5 alpha,8 alpha)-2-oxo-1(10),3,7(11)-guaiatrien-12,8-olide (3) and (1 alpha,2 beta,5 alpha,8 alpha 10 alpha)-1,10-epoxy-2-hydroxy-3,7(11)-guaiadien-12,8-olide (4), along with 16 known compounds (5-20). The structures of the isolated compounds were elucidated on the basis of spectroscopic and chemical analyses. The isolated compounds were tested for their inhibitory activity on the metabolism mediated by CYP3A4 or CYP2D6 using [N-methyl-(14)C]erythromycin or [O-methyl-(14)C]dextromethorphan as a substrate, respectively. The compounds (8R,8'R,9'S)-5-methoxyclusin (2), (-)-clusin (10), (-)-yatein (13), ethoxyclusin (15), and (-)-dihydroclusin (17), having one methylenedioxyphenyl moiety in their structures, showed very potent and selective inhibitory activity against CYP3A4 with IC(50) values (0.44-1.0 microM) identical to that of the positive control, ketoconazole (IC(50), 0.72 microM). PMID:15679319

Usia, Tepy; Watabe, Tadashi; Kadota, Shigetoshi; Tezuka, Yasuhiro

2005-01-01

338

Cancer immunotherapy using a potent immunodominant CTL epitope.  

PubMed

Immunotherapy has emerged as a promising approach that can be used in conjunction with conventional chemotherapy and radiotherapy to further improve the survival rate of patients with advanced cancer. We have recently shown in previous studies that chemotherapy and radiation therapy can alter the tumor microenvironment and allow intratumoral vaccination to prime the adaptive immune system leading to the generation of antigen-specific cell-mediated immune responses. Here, we investigated whether intratumoral injection of a foreign immunodominant peptide (GP33) and the adjuvant CpG into tumors following cisplatin chemotherapy could lead to potent antitumor effects and antigen-specific cell-mediated immune responses. We observed that treatment with all three agents produced the most potent antitumor effects compared to pairwise combinations. Moreover, treatment with cisplatin, CpG and GP33 was able to control tumors at a distant site, indicating that our approach is able to induce cross-presentation of the tumor antigen. Treatment with cisplatin, CpG and GP33 also enhanced the generation of GP33-specific and E7-specific CD8+ T cells and decreased the number of MDSCs in tumor loci, a process found to be mediated by the Fas-FasL apoptosis pathway. The treatment regimen presented here represents a universal approach to cancer control. PMID:25245934

Song, Liwen; Yang, Ming-Chieh; Knoff, Jayne; Sun, Zu-Yue; Wu, T-C; Hung, Chien-Fu

2014-10-21

339

Potent heterocyclic ligands for human complement c3a receptor.  

PubMed

The G-protein coupled receptor (C3aR) for human inflammatory protein complement C3a is an important component of immune, inflammatory, and metabolic diseases. A flexible compound (N2-[(2,2-diphenylethoxy)acetyl]-l-arginine, 4), known as a weak C3aR antagonist (IC50 ?M), was transformed here into potent agonists (EC50 nM) of human macrophages (Ca(2+) release in HMDM) by incorporating aromatic heterocycles. Antagonists were also identified. A linear correlation between binding affinity for C3aR and calculated hydrogen-bond interaction energy of the heteroatom indicated that its hydrogen-bonding capacity influenced ligand affinity and function mediated by C3aR. Hydrogen-bond accepting heterocycles (e.g., imidazole) conferred the highest affinity and agonist potency (e.g., 21, EC50 24 nM, Ca(2+), HMDM) with comparable efficacy and immunostimulatory activity as that of C3a in activating human macrophages (Ca(2+), IL1?, TNF?, CCL3). These potent and selective modulators of C3aR, inactivated by a C3aR antagonist, are stable C3a surrogates for interrogating roles for C3aR in physiology and disease. PMID:25259874

Reid, Robert C; Yau, Mei-Kwan; Singh, Ranee; Hamidon, Johan K; Lim, Junxian; Stoermer, Martin J; Fairlie, David P

2014-10-23

340

Continuum models for the contact line problem  

NASA Astrophysics Data System (ADS)

Continuum models are derived for the moving contact line problem through a combination of macroscopic and microscopic considerations. Macroscopic thermodynamic argument is used to place constraints on the form of the boundary conditions at the solid surface and the contact line. This information is then used to set up molecular dynamics to measure the detailed functional dependence of the boundary conditions. Long range molecular forces are taken into account in the form of a surface potential. This allows us to handle the case of complete wetting as well as the case of partial wetting. In particular, we obtain a new continuum model for both cases in a unified form. Two main parameters and different spreading regimes are identified from the analysis of the energy dissipations for the continuum model. Scaling laws in these different regimes are derived. The new continuum model also allows us to derive boundary conditions for the lubrication approximation. Numerical results are presented for the thin film model and the effect of the boundary condition is investigated.

Ren, Weiqing; Hu, Dan; E, Weinan

2010-10-01

341

Pose and motion from contact  

SciTech Connect

In the absence of vision, grasping an object often relies on tactile feedback from the fingertips. As the finger pushes the object, the fingertip can feel the contact point move. If the object is known in advance, from this motion the finger may infer the location of the contact point on the object, and thereby, the object pose. This paper primarily investigates the problem of determining the pose (orientation and position) and motion (velocity and angular velocity) of a planar object with known geometry from such contact motion generated by pushing. A dynamic analysis of pushing yields a nonlinear system that relates through contact the object pose and motion to the finger motion. The contact motion on the fingertip thus encodes certain information about the object pose. Nonlinear observability theory is employed to show that such information is sufficient for the finger to observe not only the pose, but also the motion of the object. Therefore, a sensing strategy can be realized as an observer of the nonlinear dynamic system. Two observers are subsequently introduced. The first observer, based on the work of Gautheir, Hammouri, and Othman (1992), has its gain determined by the solution of a Lyapunov-like equation; it can be activated at any time instant during a push. The second observer, based on Newton`s method, solves for the initial (motionless) object pose from three intermediate contact points during a push. Under the Coulomb-friction model, the paper deals with support friction in the plane and/or contact friction between the finger and the object. Extensive simulations have been done to demonstrate the feasibility of the two observers. Preliminary experiments (with an Adept robot) have also been conducted. A contact sensor has been implemented using strain gauges.

Jia, Y.B.; Erdmann, M. [Carnegie Mellon Univ., Pittsburgh, PA (United States). Robotics Inst.] [Carnegie Mellon Univ., Pittsburgh, PA (United States). Robotics Inst.

1999-05-01

342

Method for lubricating contacting surfaces  

SciTech Connect

A method is provided for tribological lubrication of sliding contact surfaces, where two surfaces are in contact and in motion relative to each other, operating in a vapor-phase environment containing at least one alcohol compound at a concentration sufficiently high to provide one monolayer of coverage on at least one of the surfaces, where the alcohol compound continuously reacts at the surface to provide lubrication.

Dugger, Michael T. (Tijeras, NM); Ohlhausen, James A. (Albuquerque, NM); Asay, David B. (Boalsburg, PA); Kim, Seong H. (State College, PA)

2011-12-06

343

Allergic contact dermatitis in Iran.  

PubMed

The frequency of sensitization to contact allergens varies in different countries because of both genetic and, more importantly, allergen exposure variations. The objective is to determine the frequency of sensitization to contact allergens in Iranian patients with dermatitis. 250 patients with a clinical diagnosis of contact dermatitis and/or atopic dermatitis were evaluated with a 28-allergen screening series recommended by the German Contact Dermatitis Research Group from September 2002 to April 2004 in Tehran, Iran. The patches were applied on the back of the patients, removed after 24 hr and the readings were taken on 24 hr, 48 hr and 72 hr after application. 126 patients (50.4%) showed at least 1 positive reaction, and 23 patients (9.2%) had more than 2 positive reactions. 189 (84.4%) of 224 positive reactions had past and/or present clinical relevance. The 5 most common allergens were nickel sulfate 70 (28.0%), cobalt chloride 32 (12.8%), para-tertiarybutyl phenol formaldehyde resin 20 (8.0%), potassium dichromate 13 (5.2%) and colophony 13 (5.2%). Contact allergy to nickel sulfate was significantly more common in female patients and in patients under 40 years of age (P < 0.05). Nickel sulfate is the most common contact allergen in Iran, mostly affecting women and younger patients probably because of more exposure. PMID:15811031

Kashani, Mansour Nassiri; Gorouhi, Farzam; Behnia, Feraydoun; Nazemi, Mohammad Javad; Dowlati, Yahya; Firooz, Alireza

2005-03-01

344

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

345

Form classification  

NASA Astrophysics Data System (ADS)

The problem of form classification is to assign a single-page form image to one of a set of predefined form types or classes. We classify the form images using low level pixel density information from the binary images of the documents. In this paper, we solve the form classification problem with a classifier based on the k-means algorithm, supported by adaptive boosting. Our classification method is tested on the NIST scanned tax forms data bases (special forms databases 2 and 6) which include machine-typed and handwritten documents. Our method improves the performance over published results on the same databases, while still using a simple set of image features.

Reddy, K. V. Umamaheswara; Govindaraju, Venu

2008-01-01

346

Crane-Load Contact Sensor  

NASA Technical Reports Server (NTRS)

An electronic instrument has been developed as a prototype of a portable crane-load contact sensor. Such a sensor could be helpful in an application in which the load rests on a base in a horizontal position determined by vertical alignment pins (see Figure 1). If the crane is not positioned to lift the load precisely vertically, then the load can be expected to swing once it has been lifted clear of the pins. If the load is especially heavy, large, and/or fragile, it could hurt workers and/or damage itself and nearby objects. By indicating whether the load remains in contact with the pins when it has been lifted a fraction of the length of the pins, the crane-load contact sensor helps the crane operator determine whether it is safe to lift the load clear of the pins: If there is contact, then the load is resting against the sides of the pins and, hence, it may not be safe to lift; if contact is occasionally broken, then the load is probably not resting against the pins, so it should be safe to lift. It is assumed that the load and base, or at least the pins and the surfaces of the alignment holes in the load, are electrically conductive, so the instrument can use electrical contact to indicate mechanical contact. However, DC resistance cannot be used as an indicator of contact for the following reasons: The load and the base are both electrically grounded through cables (the load is grounded through the lifting cable of the crane) to prevent discharge of static electricity. In other words, the DC resistance between the load and the pins is always low, as though they were always in direct contact. Therefore, instead of DC resistance, the instrument utilizes the AC electrical impedance between the pins and the load. The signal frequency used in the measurement is high enough (.1 MHz) that the impedance contributed by the cables and the electrical ground network of the building in which the crane and the base are situated is significantly greater than the contact impedance between the pins and the load. The instrument includes a signal generator and voltage-measuring circuitry, and is connected to the load and the base as shown in Figure 2. The output of the signal generator (typically having amplitude of the order of a volt) is applied to the load via a 50-resistor, and the voltage between the load and the pins is measured. When the load and the pins are not in contact, the impedance between them is relatively high, causing the measured voltage to exceed a threshold value. When the load and the pins are in contact, the impedance between them falls to a much lower value, causing the voltage to fall below the threshold value. The voltage-measuring circuitry turns on a red light-emitting diode (LED) to indicate the lower-voltage/ contact condition. Whenever the contact has been broken and the non-contact/higher-voltage condition has lasted for more than 2 ms, the voltage-measuring circuitry indicates this condition by blinking a green LED.

Youngquist, Robert; Mata, Carlos; Cox, Robert

2005-01-01

347

RF Sputtering of Gold Contacts On Niobium  

NASA Technical Reports Server (NTRS)

Reliable gold contacts are deposited on niobium by combination of RF sputtering and photolithography. Process results in structures having gold only where desired for electrical contact. Contacts are stable under repeated cycling from room temperature to 4.2 K and show room-temperature contact resistance as much as 40 percent below indium contacts made by thermalcompression bonding.

Barr, D. W.

1983-01-01

348

Solar cell with back side contacts  

DOEpatents

A III-V solar cell is described herein that includes all back side contacts. Additionally, the positive and negative electrical contacts contact compoud semiconductor layers of the solar cell other than the absorbing layer of the solar cell. That is, the positive and negative electrical contacts contact passivating layers of the solar cell.

Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J; Wanlass, Mark Woodbury; Clews, Peggy J

2013-12-24

349

Measuring The Contact Resistances Of Photovoltaic Cells  

NASA Technical Reports Server (NTRS)

Simple method devised to measure contact resistances of photovoltaic solar cells. Method uses readily available equipment and applicable at any time during life of cell. Enables evaluation of cell contact resistance, contact-end resistance, contact resistivity, sheet resistivity, and sheet resistivity under contact.

Burger, D. R.

1985-01-01

350

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

E-print Network

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

Siah, Sin Cheng

351

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

PubMed

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

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

2001-06-15

352

2-(4-aminophenyl) benzothiazole: a potent and selective pharmacophore with novel mechanistic action towards various tumour cell lines.  

PubMed

2-(4-aminophenyl) benzothiazole (CJM -126) (Table 1 (1) and its analogues represent a potent and highly selective class of antitumor agents. These compounds in nanomolar range elicit potent growth inhibition in human-derived breast, colon, ovarian and renal tumour cell lines. Metabolism of benzothiazole plays a central role in its mode of action. Cytocrome P450 isoform, CYP1A1, biotransforms benzothiazoles, to active, as well as inactive metabolites. In vitro studies had confirmed that N-oxidation and N-acetylation (only 3' halogen congener) as main active metabolic transformation (generating cytotoxic electrophilic species), while C-6 oxidation and N-acetylation (except 3' halogen congener) as inactive metabolic transformation pathway. Generation of an inactive metabolite 2-(4-aminophenyl)-6-hydoxybenzothiazole [6-OH 126, (Table 1) (10)] is blocked by fluorinated analogue, substituted around benzothiazole nucleus, especially at 5-position. National Cancer Institute (NCI), USA, confirms this series as a unique mechanistic class distinct from clinically used chemotherapeutic agents. Benzothiazoles are potent aryl hydrocarbon receptor (AhR) agonists, binding to AhR results in induction of CYP1A1, causes generation of electrophilic reactive species which forms DNA adduct, ultimately resulting in cell death by activation of apoptotic machinery. To overcome the poor physiochemical and pharmaceutical properties (bioavailability problem) of this compounds, prodrug of benzothiazole derivatives were synthesized, which are introduced in clinical trails. PMID:16787373

Dubey, Raghvendra; Shrivastava, Prabhat K; Basniwal, Pawan K; Bhattacharya, Snehendu; Moorthy, Narayana S Hari Narayana

2006-06-01

353

Healthy Contact Lens Wear and Care  

MedlinePLUS

... Submit What's this? Submit Button CDC Features Healthy Contact Lens Wear and Care Share Compartir You only ... a hot tub or swimming. Your Supplies Your Contact Lenses Rub and rinse your contact lenses with ...

354

Contact Information - Trans-NIH Angiogenesis Workshop  

Cancer.gov

Meetings & Events Home Agenda Speaker Biosketches Abstracts Logistics Contact Contact Information POINT OF CONTACT Capital Consulting Corporation is providing logistical support for this meeting. If you have questions or need assistance,

355

BUSINESS APPLICATION SECTION 1: BUSINESS CONTACT INFORMATION  

E-print Network

BUSINESS APPLICATION SECTION 1: BUSINESS CONTACT INFORMATION Sponsor: Company Name: Contact Name: Contact Address: Phone | Fax E-mail Type of Business Sole proprietorship Corporation Partnership Limited Liability Company SECTION 2: BUSINESS INFORMATION New Business Existing NYS Business Expanding

Suzuki, Masatsugu

356

Spinosad is a potent inhibitor of canine P-glycoprotein.  

PubMed

Inhibition of the drug transporter P-glycoprotein (P-gp) by the oral flea preventative spinosad has been suggested as the underlying cause of the drug-drug interaction with ivermectin. In this study, an in vitro model consisting of canine cells was validated to describe the inhibitory effect of drugs on canine P-gp. In this model, ivermectin, cyclosporin, verapamil, loperamide and ketoconazole inhibited P-gp function with IC50 values ranging from 0.1 to 3.7 ?mol/L. Spinosad was a potent inhibitor of canine P-gp with an IC50 value of 0.27 ?mol/L or 0.2 ?g/mL. The risk of spinosad causing P-gp related drug-drug interactions in the dog could be predicted by the IC50 value, the oral dosage and plasma concentrations. PMID:24582422

Schrickx, Johannes A

2014-04-01

357

Engineered repressors are potent inhibitors of androgen receptor activity  

PubMed Central

Prostate cancer growth is dependent upon the Androgen Receptor (AR) pathway, hence therapies for this disease often target this signalling axis. Such therapies are successful in the majority of patients but invariably fail after a median of 2 years and tumours progress to a castrate resistant stage (CRPC). Much evidence exists to suggest that the AR remains key to CRPC growth and hence remains a valid therapeutic target. Here we describe a novel method to inhibit AR activity, consisting of an interaction motif, that binds to the AR ligand-binding domain, fused to repression domains. These ‘engineered repressors’ are potent inhibitors of AR activity and prostate cancer cell growth and importantly inhibit the AR under circumstances in which conventional therapies would be predicted to fail, such as AR mutation and altered cofactor levels. PMID:24659630

Brooke, Greg N.; Powell, Sue M.; Lavery, Derek N.; Waxman, Jonathan; Buluwela, Laki; Ali, Simak; Bevan, Charlotte L.

2014-01-01

358

Discovery of Potent and Reversible Monoacylglycerol Lipase Inhibitors  

PubMed Central

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

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

2011-01-01

359

Lauroylethanolamide is a potent competitive inhibitor of lipoxygenase activity.  

PubMed

The lipoxygenase (LOX) pathway was proposed to compete with hydrolysis and be partly responsible for the metabolism of polyunsaturated N-acylethanolamines (PU-NAEs). Treatment of Arabidopsis seedlings with lauroylethanolamide (NAE 12:0) resulted in elevated levels of PU-NAE species, and this was most pronounced in plants with reduced NAE hydrolase activity. Enzyme activity assays revealed that NAE 12:0 inhibited LOX-mediated oxidation of PU lipid substrates in a dose-dependent and competitive manner. NAE 12:0 was 10-20 times more potent an inhibitor of LOX activities than lauric acid (FFA 12:0). Furthermore, treatment of intact Arabidopsis seedlings with NAE 12:0 (but not FFA 12:0) substantially blocked the wound-induced formation of jasmonic acid (JA), suggesting that NAE 12:0 may be used in planta to manipulate oxylipin metabolism. PMID:20541546

Keereetaweep, Jantana; Kilaru, Aruna; Feussner, Ivo; Venables, Barney J; Chapman, Kent D

2010-07-16

360

2-amino and 2'-aminocombretastatin derivatives as potent antimitotic agents.  

PubMed

A novel series of 2-amino and 2'-aminocombretastatin derivatives were synthesized and evaluated for antitumor activity. Several compounds had excellent antiproliferative activity as inhibitors of tubulin polymerization. Compounds 11, 20, and 21 with IC(50) values of 1.6, 1.7, and 1.8 microM, respectively, exhibited more potent inhibition of tubulin polymerization than colchicine and approximately as active as combretastatin A-4. They also displayed antiproliferative activity with an IC(50) values ranging from 11 to 44 nM in a variety of human cell lines from different organs. Structure activity relationship information suggests that the NH(2) substituent at the 2-position of either ring A or ring B in combretastatin molecular skeleton may play an important role in the bioactivity of this series of compounds. PMID:17034147

Chang, Jang-Yang; Yang, Ming-Fang; Chang, Chi-Yen; Chen, Chi-Ming; Kuo, Ching-Chuan; Liou, Jing-Ping

2006-10-19

361

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

362

Maleopimaric acid--a potent sensitizer in modified rosin.  

PubMed

The allergenicity of the maleic-modified rosins and their esters has been studied. The unesterified resins are mainly used in paper size and the esters in printing inks, varnishes and adhesives. The levopimaric-maleic anhydride Diels-Alder adduct (maleopimaric acid) is the main component obtained in the maleic-modified rosins. This compound was synthesized and its structure was determined. Its sensitizing potential was investigated in guinea pigs according to different methods. It was shown that maleopimaric acid is a very potent sensitizer, comparable with the strongest allergen isolated from unmodified gum rosin. The allergen may also be present after esterification unless the process is carried out to completion. The animals sensitized to maleopimaric acid did not react to unmodified rosin, which shows that maleopimaric acid is structurally different from the allergens in rosin. PMID:2347173

Karlberg, A T; Gäfvert, E; Hagelthorn, G; Nilsson, J L

1990-04-01

363

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

364

Deoxygedunin, a Natural Product with Potent Neurotrophic Activity in Mice  

PubMed Central

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

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

2010-01-01

365

Marine algae: screening for a potent antibacterial agent.  

PubMed

This study was done to investigate the antimicrobial potentiality of the marine algae collected from different coastal regions of Gujarat and screened for the same. Twenty-six marine algae belonging to Rhodophyceae, Chlorophyceae and Phaeophyceae were screened for their potential antibacterial activity against five clinically important bacterial strains, namely Bacillus cereus, Micrococcus flavus, Citrobacter freundii, Klebsiella pneumoniae and Pseudomonas testosterone. Acetone and methanol were used for extraction; and the extracted yield was more when the solvent used was methanol. The antibacterial activity was done by both Agar disc diffusion method and Agar ditch method. The five bacterial strains showed varied response towards marine algal extracts. The most susceptible bacteria was B. cereus followed by K. pneumoniae and C. freundii while the most resistant bacteria were M. flavus and P. testosteroni. Among the 26 algae screened, E. intestinalis was the most potent alga and thus, this alga was selected for further studies. E. intestinalis was extracted in petroleum ether, 1,4-dioxan, acetone, methanol and DMF, and their antibacterial activity was studied against the above-stated five bacterial strains using agar disc method. Maximum extractive value of E. intestinalis was in methanol (2.05%) and minimum was in acetone (0.38%). The most susceptible bacteria was K. pneumoniae and maximum antibacterial activity was shown by petroleum ether extract and minimum was shown by 1,4-dioxan extract. The most resistant bacteria were M. flavus and C. freundii. The MIC values of E. intestinalis extracts ranged from 2500-9.765 microg/0.5 ml against B. cereus and K. pneumoniae. From these results it is concluded that the acetone extract of E. intestinalis is the most potent extract and can be used as a lead molecule in drug discovery in inhibiting some of the bacterial strains. E. intestinalis can be used as a promising novel marine antimicrobial agent in the coming years. PMID:17594989

Nair, Ratish; Chabhadiya, Rajesh; Chanda, Sumitra

2007-01-01

366

Maresins: novel macrophage mediators with potent antiinflammatory and proresolving actions  

PubMed Central

The endogenous cellular and molecular mechanisms that control acute inflammation and its resolution are of wide interest. Using self-resolving inflammatory exudates and lipidomics, we have identified a new pathway involving biosynthesis of potent antiinflammatory and proresolving mediators from the essential fatty acid docosahexaenoic acid (DHA) by macrophages (M?s). During the resolution of mouse peritonitis, exudates accumulated both 17-hydroxydocosahexaenoic acid, a known marker of 17S-D series resolvin (Rv) and protectin biosynthesis, and 14S-hydroxydocosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid from endogenous DHA. Addition of either DHA or 14S-hydroperoxydocosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid to activated M?s converted these substrates to novel dihydroxy-containing products that possessed potent antiinflammatory and proresolving activity with a potency similar to resolvin E1, 5S,12R,18R-trihydroxyeicosa-6Z,8E,10E,14Z,16E-pentaenoic acid, and protectin D1, 10R,17S-dihydroxydocosa-4Z,7Z,11E,13E,15Z,19Z-hexaenoic acid. Stable isotope incorporation, intermediate trapping, and characterization of physical and biological properties of the products demonstrated a novel 14-lipoxygenase pathway, generating bioactive 7,14-dihydroxydocosa-4Z,8,10,12,16Z,19Z-hexaenoic acid, coined M? mediator in resolving inflammation (maresin), which enhances resolution. These findings suggest that maresins and this new metabolome may be involved in some of the beneficial actions of DHA and M?s in tissue homeostasis, inflammation resolution, wound healing, and host defense. PMID:19103881

Serhan, Charles N.; Yang, Rong; Martinod, Kimberly; Kasuga, Kie; Pillai, Padmini S.; Porter, Timothy F.; Oh, Sungwhan F.; Spite, Matthew

2009-01-01

367

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

368

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

369

Approximate stresses in 2-D flat elastic contact fretting problems  

NASA Astrophysics Data System (ADS)

Fatigue results from the cyclic loading of a solid body. If the body subject to fatigue is in contact with another body and relative sliding motion occurs between these two bodies, then rubbing surface damage can accelerate fatigue failure. The acceleration of fatigue failure is especially important if the relative motion between the two bodies results in surface damage without excessive surface removal via wear. The situation just described is referred to as fretting fatigue. Understanding of fretting fatigue is greatly enhanced if the stress state associated with fretting can be characterized. For Hertzian contact, this can readily be done. Unfortunately, simple stress formulae are not available for flat body contact. The primary result of the present research is the development of a new, reasonably accurate, approximate closed form expression for 2-dimensional contact stresses which has been verified using finite element modeling. This expression is also combined with fracture mechanics to provide a simple method of determining when a crack is long enough to no longer be affected by the contact stress field. Lower bounds on fatigue life can then easily be calculated using fracture mechanics. This closed form expression can also be used to calculate crack propagation within the contact stress field. The problem of determining the cycles required to generate an initial crack and what to choose as an initial crack size is unresolved as it is in non-fretting fatigue.

Urban, Michael Rene

370

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

371

Dermatitis, contact on the cheek (image)  

MedlinePLUS

... skin inflammation (dermatitis) on the cheek caused by contact with a substance that produced an allergic reaction (allergen). Contact dermatitis causes redness, itching, and small blisters (vesicles).

372

Mechanisms of current flow in metal-semiconductor ohmic contacts  

SciTech Connect

Published data on the properties of metal-semiconductor ohmic contacts and mechanisms of current flow in these contacts (thermionic emission, field emission, thermal-field emission, and also current flow through metal shunts) are reviewed. Theoretical dependences of the resistance of an ohmic contact on temperature and the charge-carrier concentration in a semiconductor were compared with experimental data on ohmic contacts to II-VI semiconductors (ZnSe, ZnO), III-V semiconductors (GaN, AlN, InN, GaAs, GaP, InP), Group IV semiconductors (SiC, diamond), and alloys of these semiconductors. In ohmic contacts based on lightly doped semiconductors, the main mechanism of current flow is thermionic emission with the metal-semiconductor potential barrier height equal to 0.1-0.2 eV. In ohmic contacts based on heavily doped semiconductors, the current flow is effected owing to the field emission, while the metal-semiconductor potential barrier height is equal to 0.3-0.5 eV. In alloyed In contacts to GaP and GaN, a mechanism of current flow that is not characteristic of Schottky diodes (current flow through metal shunts formed by deposition of metal atoms onto dislocations or other imperfections in semiconductors) is observed.

Blank, T. V., E-mail: tblank@mail.ioffe.ru; Gol'dberg, Yu. A. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

2007-11-15

373

Morphology and the Strength of Intermolecular Contact in Protein Crystals  

NASA Technical Reports Server (NTRS)

The strengths of intermolecular contacts (macrobonds) in four lysozyme crystals were estimated based on the strengths of individual intermolecular interatomic interaction pairs. The periodic bond chain of these macrobonds accounts for the morphology of protein crystals as shown previously. Further in this paper, the surface area of contact, polar coordinate representation of contact site, Coulombic contribution on the macrobond strength, and the surface energy of the crystal have been evaluated. Comparing location of intermolecular contacts in different polymorphic crystal modifications, we show that these contacts can form a wide variety of patches on the molecular surface. The patches are located practically everywhere on this surface except for the concave active site. The contacts frequently include water molecules, with specific intermolecular hydrogen-bonds on the background of non-specific attractive interactions. The strengths of macrobonds are also compared to those of other protein complex systems. Making use of the contact strengths and taking into account bond hydration we also estimated crystal-water interfacial energies for different crystal faces.

Matsuura, Yoshiki; Chernov, Alexander A.

2002-01-01

374

Shape and eccentricity effects in adhesive contacts of rodlike particles.  

PubMed

The effects of shape and eccentricity on adhesion and detachment behavior of long, rodlike particles in contact with a half-space are analyzed using contact mechanics. The particles are considered to have cross sections that are squarish, oblate, or prolate rather than circular. Such cross sections are represented very generally by using superellipses. The contact mechanics model allows deduction of closed-form expressions for the contact pressure, load-contact size relation, detachment load, and detachment contact size. It is found that even relatively small deviations in shape from a cylinder have a significant influence on the detachment load. Eccentricity also affects the adhesive behavior, but to a lesser extent, with oblate shapes requiring larger separation loads than prolate shapes. The load-contact size solution reduces to that for a right-circular, cylindrical rod when the appropriate limit is taken. The detachment behavior of right-circular cylinders is also found to be mimicked by an entire family of rod shapes with different cross sections. PMID:21882834

Sundaram, Narayan; Chandrasekar, Srinivasan

2011-10-18

375

Specific contact resistance measurements of the screen-printed Ag thick film contacts in the silicon solar cells by three-point probe methodology and TLM method  

Microsoft Academic Search

The specific contact resistance of the screen-printed Ag contacts in the silicon solar cells has been investigated by applying\\u000a two independent test methodologies such as three-point probe (TPP) and well-known transfer length model (TLM) test structure\\u000a respectively. This paper presents some comparative results obtained with these two measurement techniques for the screen-printed\\u000a Ag contacts formed on the porous silicon antireflection

P. N. Vinod

376

Ball bearing lubrication: The elastohydrodynamics of elliptical contacts  

NASA Technical Reports Server (NTRS)

The history of ball bearings is examined, taking into account rollers and the wheel in the early civilizations, the development of early forms of rolling-element bearings in the classical civilizations, the Middle Ages, the Industrial Revolution, the emergence of the precision ball bearing, scientific studies of contact mechanics and rolling friction, and the past fifty years. An introduction to ball bearings is presented, and aspects of ball bearing mechanics are explored. Basic characteristics of lubrication are considered along with lubrication equations, the lubrication of rigid ellipsoidal solids, and elastohydrodynamic lubrication theory. Attention is given to the theoretical results for fully flooded elliptical hydrodynamic contacts, the theoretical results for starved elliptical contacts, experimental investigations, the elastohydrodynamics of elliptical contacts for materials of low elastic modulus, the film thickness for different regimes of fluid-film lubrication, and applications.

Hamrock, B. J.; Dowson, D.

1981-01-01

377

Liquid bridge stability and breakup with a receding contact line  

NASA Astrophysics Data System (ADS)

We have used experimental and theoretical methods to study the evolution and pinch-off of a liquid bridge fixed at the upper attachment point, but with a free contact line at the lower attachment point. High speed video shows that the contact line motion consists of two stages: a slow retraction at the beginning and a rapid retraction immediately prior to the bridge pinch-off. During the first stage, the evolution is quasi-static, and only a function of the bridge's height and volume. Agreement between experiments and solutions to the Young-Laplace equation is excellent during this phase. At some point, however, the static solution becomes unstable, and the contact line retreats rapidly, pinching off to form a droplet on the substrate. Theoretical and numerical approaches are used to analyse and predict this motion. Excellent agreement with experiments is achieved using a Tanner-like formulation for the dynamic contact angle.

Breuer, Kenneth; Qian, Bian

2009-11-01

378

Flow-forming and flow formability simulation  

Microsoft Academic Search

Forward flow forming of tubes have been simulated using an explicit commercial finite element program. Variation of contact\\u000a geometry considering plastic flow has been calculated based on the proposed criterion. Also flow formability of tube materials\\u000a have been calculated during forward flow-forming process. Contact geometry simulation results as the variation of S-to-L ratios with feed rates and two attack angles

M. H. Parsa; A. M. A. Pazooki; M. Nili Ahmadabadi

2009-01-01

379

Thermal and electrical contact conductance studies  

NASA Technical Reports Server (NTRS)

Prediction of electrical and thermal contact resistance for pressed, nominally flat contacts is complicated by the large number of variables which influence contact formation. This is reflected in experimental results as a wide variation in contact resistances, spanning up to six orders of magnitude. A series of experiments were performed to observe the effects of oxidation and surface roughness on contact resistance. Electrical contact resistance and thermal contact conductance from 4 to 290 K on OFHC Cu contacts are reported. Electrical contact resistance was measured with a 4-wire DC technique. Thermal contact conductance was determined by steady-state longitudinal heat flow. Corrections for the bulk contribution ot the overall measured resistance were made, with the remaining resistance due solely to the presence of the contact.

Vansciver, S. W.; Nilles, M.

1985-01-01

380

Imaging surface contacts: Power law contact distributions and contact stresses in quartz, calcite, glass and acrylic plastic  

USGS Publications Warehouse

A procedure has been developed to obtain microscope images of regions of contact between roughened surfaces of transparent materials, while the surfaces are subjected to static loads or undergoing frictional slip. Static loading experiments with quartz, calcite, soda-lime glass and acrylic plastic at normal stresses to 30 MPa yield power law distributions of contact areas from the smallest contacts that can be resolved (3.5 ??m2) up to a limiting size that correlates with the grain size of the abrasive grit used to roughen the surfaces. In each material, increasing normal stress results in a roughly linear increase of the real area of contact. Mechanisms of contact area increase are by growth of existing contacts, coalescence of contacts and appearance of new contacts. Mean contacts stresses are consistent with the indentation strength of each material. Contact size distributions are insensitive to normal stress indicating that the increase of contact area is approximately self-similar. The contact images and contact distributions are modeled using simulations of surfaces with random fractal topographies. The contact process for model fractal surfaces is represented by the simple expedient of removing material at regions where surface irregularities overlap. Synthetic contact images created by this approach reproduce observed characteristics of the contacts and demonstrate that the exponent in the power law distributions depends on the scaling exponent used to generate the surface topography.

Dieterich, J.H.; Kilgore, B.D.

1996-01-01

381

Form approved:  

Cancer.gov

RETURNED AGENTS LIST Use one form for each Agent and Protocol NCI Protocol Number: Return. No.: Institution Address: Date Received: Principal Investigator (PI) for Study (Please type or print): Signature of Authorizing Official: Date of Return Shipment: Signature

382

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.

383

Carter Tribley Butts Contact Information  

E-print Network

High School, May 1992 Current Position: · Professor, Department of Sociology and InstituteCarter Tribley Butts Contact Information: · Work: Department of Sociology SSPA 2145 University: http://research.carterbutts.com/ Education: · Ph.D. in Sociology, Carnegie Mellon University, May 2002

Loudon, Catherine

384

Contact Allergy in Agricultural Workers  

Microsoft Academic Search

Agricultural workers (n = 121) referred to the Nofer Institute of Occupational Medicine for suspected occupational disease were subjected to dermatological and allergological examinations. All were patch and prick tested with standard occupational and environmental allergen sets. Contact dermatitis was diagnosed in 60 (49.6%) patients. In the women, the dominant allergy was that to nickel, benzalkonium, palladium, cobalt, thimerosal, fragrances

Marta Kiec-Swierczynska; Beata Krecisz; Dominika Swierczynska-Machura

2003-01-01

385

Media Inquiries Contact: Thomas Carey  

E-print Network

Media Inquiries Contact: Thomas Carey BioCentury Publications, Inc. tcarey@biocentury.com +1 650 their innovative science to the healthcare community. So, SciBX is a unique literature awareness and educational the newest developments in the lab into innovative healthcare solutions. This coverage is complemented

Cai, Long

386

STUDENT SUPPORT SERVICES Contact Information  

E-print Network

and academic issues. Recreation, entertainment, clubs and societies. Welfare Service open all year roundSTUDENT SUPPORT SERVICES Contact Information Academic Counsellors Students will be advised of names. Centre for Academic Practice JA & JH - 548 4064 Graham Hills Building, Room 2.08 · Time management

Mottram, Nigel

387

Dextrous manipulation with rolling contacts  

Microsoft Academic Search

Dextrous manipulation is a problem of paramount importance in the study of multifingered robotic hands. Given a grasped object, the main objectives are: (a) generate trajectories for the finger joints so that through the effects of contact constraints, the object can be transferred to a goal grasp configuration; and (b) derive control algorithms to realize planned trajectories. In this paper,

L. Han; Y. S. Guan; Z. X. Li; Q. Shi; J. C. Trinkle

1997-01-01

388

DISEASES CAUSED BY WATER CONTACT  

EPA Science Inventory

Diseases associated with water contact are reviewed with respect to the sources of etiological agents, the types of diseases and the conditions under which they occur. The sources of disease agents fall into three general groups; point sources such as sewage treatment plants; dis...

389

PROCEDURE CARDS EMERGENCY CONTACT INFORMATION  

E-print Network

/Wilmington Campus Phones 911 Georgetown/Lewes Campus Phones (9) 911 From a cell phone (302) 831-2222 Red PhonesLABORATORY EMERGENCY PROCEDURE CARDS EMERGENCY CONTACT INFORMATION Public Safety Newark in the area If the spill is small and if you are trained and it is safe to do so: 1. Use appropriate

Firestone, Jeremy

390

Eugene Kiselev Office Contact Information  

E-print Network

South Street Waltham, Ma 02454 Personal Contact Information 180 B River Street, Apartment 3 Waltham, MA Research Associate, Russian State University of Oil and Gas, Moscow Russia (Telecommuting) June 2011 of geopolitics and international security - particularly on the energy security of Russia and Central Asia

Snider, Barry B.

391

Animal behaviour Eye contact enhances  

E-print Network

an impor- tant role in how much the individuals like each other by the end of the evening. However for understand- ing the role of eye contact as a controlling signal in human non-verbal social behaviour such as face detection (Conty et al. 2006), gender discrimination (Macrae et al. 2002) and iden- tity encoding

Hamilton, Antonia

392

Electrical contact tool set station  

DOEpatents

An apparatus is provided for the precise setting to zero of electrically conductive cutting tools used in the machining of work pieces. An electrically conductive cylindrical pin, tapered at one end to a small flat, rests in a vee-shaped channel in a base so that its longitudinal axis is parallel to the longitudinal axis of the machine's spindle. Electronic apparatus is connected between the cylindrical pin and the electrically conductive cutting tool to produce a detectable signal when contact between tool and pin is made. The axes of the machine are set to zero by contact between the cutting tool and the sides, end or top of the cylindrical pin. Upon contact, an electrical circuit is completed, and the detectable signal is produced. The tool can then be set to zero for that axis. Should the tool contact the cylindrical pin with too much force, the cylindrical pin would be harmlessly dislodged from the vee-shaped channel, preventing damage either to the cutting tool or the cylindrical pin. 5 figs.

Byers, M.E.

1988-02-22

393

NASA Space Grant Contacts Directory  

NSDL National Science Digital Library

This publication provides an overview of two NASA funding programs, the National Space Grant College and Fellowship Program (Space Grant) and the Experimental Program to Stimulate Competitive Research (EPSCOR). A listing of contacts for these programs in all 50 states (20 states for EPSCOR), the District of Columbia, and Puerto Rico is provided, as well as a link to the Space Grant homepage.

394

February 29, 2012 Media Contact  

E-print Network

February 29, 2012 Media Contact: Chris Lechuga Public Affairs Specialist The University will receive a $1,000 cash prize, framed certificate, and a specially struck bronze medal designed by Hertzog accomplished book designers and printers, is designed to celebrate the importance of fine printing as an art

Ward, Karen

395

Assessing Measures of Contact Theory.  

ERIC Educational Resources Information Center

This paper consolidates findings from two related studies: William Brown's research on the predictive ability of measures of early and non-high school interracial contact/opportunities that appear to affect interracial attitudes and behaviors in high school; and Martin Patchen's investigation in Indianapolis, Indiana high schools analyzing the…

Brown, William R.; Patchen, Martin

396

Asynchronous Contact Mechanics David Harmon  

E-print Network

University Figure 1. A prescribed particle slowly moves through a set of curtains, then impulsively shifts: variational, symplectic, contact, collision, simulation 1 Motivation Even as computer hardware benefits from. A correctness guarantee is a pre- requisite for physical behavior that is consistent under rediscretiza- tion

Yang, Junfeng

397

How contact metamorphism can trigger global climate changes: Modeling gas generation around igneous sills in sedimentary basins  

NASA Astrophysics Data System (ADS)

Large volumes of greenhouse gases such as CH 4 and CO 2 form by contact metamorphism of organic-rich sediments in aureoles around sill intrusions in sedimentary basins. Thermogenic gas generation and dehydration reactions in shale are treated numerically in order to quantify basin-scale devolatilization. We show that aureole thicknesses, defined as the zone of elevated metamorphism relative to the background level, vary within 30-250% of the sill thickness, depending on the temperature of the host-rock and intrusion, besides the sill thickness. In shales with total organic carbon content of >5 wt.%, CH 4 is the dominant volatile (85-135 kg/m 3) generated through organic cracking, relative to H 2O-generation from dehydration reactions (30-110 kg/m 3). Even using conservative estimates of melt volumes, extrapolation of our results to the scale of sill complexes in a sedimentary basin indicates that devolatilization can have generated ˜2700-16200 Gt CH 4 in the Karoo Basin (South Africa), and ˜600-3500 Gt CH 4 in the Vøring and Møre basins (offshore Norway). The generation of volatiles is occurring on a time-scale of 10-1000 years within an aureole of a single sill, which makes the rate of sill emplacement the time-constraining factor on a basin-scale. This study demonstrates that thousands of gigatons of potent greenhouse gases like methane can be generated during emplacement of Large Igneous Provinces in sedimentary basins.

Aarnes, Ingrid; Svensen, Henrik; Connolly, James A. D.; Podladchikov, Yuri Y.

2010-12-01

398

Coupling Between Precipitation and Contact-Line Dynamics: Multiring Stains and Stick-Slip Motion  

NASA Astrophysics Data System (ADS)

The contact line in an evaporating drop can stay pinned to form a single ring or can shrink in a discontinuous stepwise manner and generate multiple rings. We demonstrate the latter with DNA solutions and attribute it to a pinning-depinning cycle that generates new contact lines. The new contact line recedes after depinning and is repinned at an internal precipitate ring that determines the location of the next contact line. Each precursor ring is formed when DNAs are trapped by an internal microstagnation flow and precipitation dynamics hence control this unsteady drop motion.

Maheshwari, Siddharth; Zhang, Lu; Zhu, Yingxi; Chang, Hsueh-Chia

2008-02-01

399

Aminoindoles, a Novel Scaffold with Potent Activity against Plasmodium falciparum?†  

PubMed Central

This study characterizes aminoindole molecules that are analogs of Genz-644442. Genz-644442 was identified as a hit in a screen of ?70,000 compounds in the Broad Institute's small-molecule library and the ICCB-L compound collection at Harvard Medical School. Genz-644442 is a potent inhibitor of Plasmodium falciparum in vitro (50% inhibitory concentrations [IC50s], 200 to 285 nM) and inhibits P. berghei in vivo with an efficacy of >99% in an adapted version of Peters' 4-day suppressive test (W. Peters, Ann. Trop. Med. Parasitol. 69:155–171, 1975). Genz-644442 became the focus of medicinal chemistry optimization; 321 analogs were synthesized and were tested for in vitro potency against P. falciparum and for in vitro absorption, distribution, metabolism, and excretion (ADME) properties. This yielded compounds with IC50s of approximately 30 nM. The lead compound, Genz-668764, has been characterized in more detail. It is a single enantiomer with IC50s of 28 to 65 nM against P. falciparum in vitro. In the 4-day P. berghei model, when it was dosed at 100 mg/kg of body weight/day, no parasites were detected on day 4 postinfection. However, parasites recrudesced by day 9. Dosing at 200 mg/kg/day twice a day resulted in cures of 3/5 animals. The compound had comparable activity against P. falciparum blood stages in a human-engrafted NOD-scid mouse model. Genz-668764 had a terminal half-life of 2.8 h and plasma trough levels of 41 ng/ml when it was dosed twice a day orally at 55 mg/kg/day. Seven-day rat safety studies showed a no-observable-adverse-effect level (NOAEL) at 200 mg/kg/day; the compound was not mutagenic in Ames tests, did not inhibit the hERG channel, and did not have potent activity against a broad panel of receptors and enzymes. Employing allometric scaling and using in vitro ADME data, the predicted human minimum efficacious dose of Genz-668764 in a 3-day once-daily dosing regimen was 421 mg/day/70 kg, which would maintain plasma trough levels above the IC90 against P. falciparum for at least 96 h after the last dose. The predicted human therapeutic index was approximately 3, on the basis of the exposure in rats at the NOAEL. We were unable to select for parasites with >2-fold decreased sensitivity to the parent compound, Genz-644442, over 270 days of in vitro culture under drug pressure. These characteristics make Genz-668764 a good candidate for preclinical development. PMID:21422215

Barker, Robert H.; Urgaonkar, Sameer; Mazitschek, Ralph; Celatka, Cassandra; Skerlj, Renato; Cortese, Joseph F.; Tyndall, Erin; Liu, Hanlan; Cromwell, Mandy; Sidhu, Amar Bir; Guerrero-Bravo, Jose E.; Crespo-Llado, Keila N.; Serrano, Adelfa E.; Lin, Jing-wen; Janse, Chris J.; Khan, Shahid M.; Duraisingh, Manoj; Coleman, Bradley I.; Angulo-Barturen, Inigo; Jiménez-Díaz, María Belén; Magán, Noemí; Gomez, Vanesa; Ferrer, Santiago; Martínez, María Santos; Wittlin, Sergio; Papastogiannidis, Petros; O'Shea, Thomas; Klinger, Jeffrey D.; Bree, Mark; Lee, Edward; Levine, Mikaela; Wiegand, Roger C.; Munoz, Benito; Wirth, Dyann F.; Clardy, Jon; Bathurst, Ian; Sybertz, Edmund

2011-01-01

400

78 FR 53507 - Agency Information Collection (Beneficiary Travel Mileage Reimbursement Application Form...  

Federal Register 2010, 2011, 2012, 2013

...Travel Mileage Reimbursement Application Form)'' in any correspondence. FOR FURTHER INFORMATION CONTACT: Crystal Rennie, Enterprise Records Service...Travel Mileage Reimbursement Application Form).'' SUPPLEMENTARY...

2013-08-29

401

Improved Electrical Contact For Dowhhole Drilling Networks  

DOEpatents

An electrical contact system for transmitting information across tool joints while minimizing signal reflections that occur at the tool joints includes a first electrical contact comprising an annular resilient material. An annular conductor is embedded within the annular resilient material and has a surface exposed from the annular resilient material. A second electrical contact is provided that is substantially equal to the first electrical contact. Likewise, the second electrical contact has an annular resilient material and an annular conductor. The two electrical contacts configured to contact one another such that the annular conductors of each come into physical contact. The annular resilient materials of each electrical contact each have dielectric characteristics and dimensions that are adjusted to provide desired impedance to the electrical contacts.

Hall, David R. (Provo, UT); Hall, Jr., H. Tracy (Provo, UT); Pixton, David S. (Lehi, UT); Dahlgren, Scott (Provo, UT); Fox, Joe (Spanish Fork, UT); Sneddon, Cameron (Provo, UT)

2005-08-16

402

Potent angiotensin-converting enzyme inhibitory tripeptides identified by a computer-based approach.  

PubMed

Currently, peptides and peptidomimetics are the main focus in attempts to identify inhibitors of angiotensin-converting enzyme (ACE), the dipeptidyl carboxypeptidase that causes blood vessels to constrict and blood pressure to increase. This study was conducted to identify the most potent ACE-inhibitory tripeptides with a proline C-terminus, using a novel three-step (tautomerization-docking-ADME simulation) virtual screening process and in vitro assays. Sixteen candidates were identified, and their IC50 values ranged from 5.6 to 274.4?M. ACE inhibition activity for 14 of the 16 tripeptides was reported for the first time. We also found that changing from the L-form to the D-form of the amino acid at the amino and carboxyl termini resulted in a decrease of inhibition, but a greater decrease was observed for C-terminal changes. With low IC50 values and high-predicted bioavailability, the peptides identified by our protocol are comparable in terms of ACE-inhibition to those derived from costly and time-consuming wet screening. Our in vitro and docking results showed that the configuration of the C-terminus is a critical parameter contributing to the inhibitory activity of tripeptides with proline at this position. These findings will contribute to the use of simulation tools for rational drug design, especially for ACE inhibitors. PMID:25181455

Hai-Bang, Tran; Shimizu, Kuniyoshi

2014-09-01

403

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

PubMed Central

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

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

2011-01-01

404

SIMULATION OF AEROSOL FORMATION IN GAS-LIQUID CONTACT DEVICES  

Microsoft Academic Search

In gas-liquid contact devices like absorbers, quench coolers, or condensers, aerosols can be formed by spontaneous phase transitions, initiated by homogeneous or heterogeneous nucleation, if a supersaturated gas phase emerges due to simultaneous heat and mass transfer processes or chemical reactions. Typical examples are the absorption of acid gases, like HCl or SO3, the condensation of solvents in the presence

A. Wix; K. Schaber; O. Ofenloch; R. Ehrig; P. Deuflhard

2007-01-01

405

Method and apparatus for producing co-current fluid contact  

DOEpatents

An improved packing system and method are disclosed wherein a packing section includes a liquid distributor and a separator placed above the distributor so that gas rising through the liquid distributor contacts liquid in the distributor, forming a gas-liquid combination which rises in co-current flow to the separator. Liquid is collected in the separator, from which gas rises. 13 figs.

Trutna, W.R.

1997-12-09

406

Method and apparatus for producing co-current fluid contact  

DOEpatents

An improved packing system and method are disclosed wherein a packing section includes a liquid distributor and a separator placed above the distributor so that gas rising through the liquid distributor contacts liquid in the distributor, forming a gas-liquid combination which rises in co-current flow to the separator. Liquid is collected in the separator, from which gas rises.

Trutna, William R. (6 Postwood, Austin, TX 78738-1503)

1997-01-01

407

Electrical contacts and conductors for megaamperes pulse currents  

Microsoft Academic Search

Summary form only given. The operation of electrical contacts and conductors in output circuits of pulse current sources, which generate current pulses of several megaamperes and duration of tens or hundreds microseconds, are considered. The admissible linear current density in conductors is defined from condition of the thermal stability of polymeric insulation. Such density is 160 kA\\/cm for steel, copper

B. E. Fridman; P. G. Rutberg

2001-01-01

408

Subleading contributions to the three-nucleon contact interaction  

SciTech Connect

We obtain a minimal form of the two-derivative three-nucleon contact Lagrangian, by imposing all constraints deriving from discrete symmetries, Fierz identities, and Poincare covariance. The resulting interaction, depending on 10 unknown low-energy constants, leads to a three-nucleon potential which we give in a local form in configuration space. We also consider the leading (no-derivative) four-nucleon interaction and show that there exists only one independent operator.

Girlanda, L. [Dipartimento di Fisica, Universita del Salento, and INFN Sezione di Lecce, Via Arnesano, I-73100 Lecce (Italy); Kievsky, A.; Viviani, M. [INFN, Sezione di Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa (Italy)

2011-07-15

409

Plants from Brazilian Cerrado with Potent Tyrosinase Inhibitory Activity  

PubMed Central

The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05) tyrosinase inhibitory activity exhibiting the IC50 value of 11.88 µg/mL, compared to kojic acid (IC50 value of 13.14 µg/mL). Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC50 value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations. PMID:23173036

Souza, Paula Monteiro; Elias, Silvia Taveira; Simeoni, Luiz Alberto; de Paula, Jose Elias; Gomes, Sueli Maria; Guerra, Eliete Neves Silva; Fonseca, Yris Maria; Silva, Elton Clementino; Silveira, Damaris; Magalhaes, Perola Oliveira

2012-01-01

410

Plants from Brazilian Cerrado with potent tyrosinase inhibitory activity.  

PubMed

The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05) tyrosinase inhibitory activity exhibiting the IC?? value of 11.88 µg/mL, compared to kojic acid (IC?? value of 13.14 µg/mL). Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC?? value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations. PMID:23173036

Souza, Paula Monteiro; Elias, Silvia Taveira; Simeoni, Luiz Alberto; de Paula, José Elias; Gomes, Sueli Maria; Guerra, Eliete Neves Silva; Fonseca, Yris Maria; Silva, Elton Clementino; Silveira, Dâmaris; Magalhães, Pérola Oliveira

2012-01-01

411

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, Ahcene

2014-01-01

412

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

413

Acetone Extract from Rhodomyrtus tomentosa: A Potent Natural Antioxidant.  

PubMed

Rhodomyrtus tomentosa (Myrtaceae) has been employed in traditional Thai medicine to treat colic diarrhoea, dysentery, abscesses, haemorrhage, and gynaecopathy. In addition, it has been used to formulate skin-whitening, anti-aging and skin beautifying agents. Ethnomedical activities of this plant may be due its antioxidant property. Hence, the aim of this study was to evaluate both in vitro and in vivo antioxidant activities of R. tomentosa leaf extract. In vitro antioxidant activity of the extract was assessed by lipid peroxidation inhibition capacity, ferric reducing antioxidant power, and metal chelating activity. R. tomentosa extract demonstrated its free radical scavenging effects in concentration dependent manner. In vivo antioxidant activity of the extract was conducted in Swiss Albino mice. Levels of thio-barbituric acid reactive substances (TBARS), glutathione (GSH), and the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in blood, liver, and kidney were analyzed using microtitre plate photometer. Administration of CCl(4) caused significant increase in TBARS and decrease in GSH, SOD, CAT and GPx levels. In contrast, R. tomentosa extract (0.8?g/kg) effectively prevented these alterations and maintained the antioxidant status. The results suggest that R. tomentosa extract can serve as a potent antioxidant. PMID:23125869

Lavanya, Goodla; Voravuthikunchai, Supayang Piyawan; Towatana, Nongporn Hutadilok

2012-01-01

414

Acetone Extract from Rhodomyrtus tomentosa: A Potent Natural Antioxidant  

PubMed Central

Rhodomyrtus tomentosa (Myrtaceae) has been employed in traditional Thai medicine to treat colic diarrhoea, dysentery, abscesses, haemorrhage, and gynaecopathy. In addition, it has been used to formulate skin-whitening, anti-aging and skin beautifying agents. Ethnomedical activities of this plant may be due its antioxidant property. Hence, the aim of this study was to evaluate both in vitro and in vivo antioxidant activities of R. tomentosa leaf extract. In vitro antioxidant activity of the extract was assessed by lipid peroxidation inhibition capacity, ferric reducing antioxidant power, and metal chelating activity. R. tomentosa extract demonstrated its free radical scavenging effects in concentration dependent manner. In vivo antioxidant activity of the extract was conducted in Swiss Albino mice. Levels of thio-barbituric acid reactive substances (TBARS), glutathione (GSH), and the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in blood, liver, and kidney were analyzed using microtitre plate photometer. Administration of CCl4 caused significant increase in TBARS and decrease in GSH, SOD, CAT and GPx levels. In contrast, R. tomentosa extract (0.8?g/kg) effectively prevented these alterations and maintained the antioxidant status. The results suggest that R. tomentosa extract can serve as a potent antioxidant. PMID:23125869

Lavanya, Goodla; Voravuthikunchai, Supayang Piyawan; Towatana, Nongporn Hutadilok

2012-01-01

415

Discovery of novel oxindole derivatives as potent ?-glucosidase inhibitors.  

PubMed

A series of 6-chloro-3-oxindole derivatives 1-25 were synthesized in high yields by the reaction of 6-chlorooxindole with different aromatic aldehydes in the presence of piperidine. All the synthesized compounds were isolated with E configuration. The structures were confirmed using spectroscopic techniques, including (1)H NMR and EIMS. These compounds showed varying degree of yeast ?-glucosidase inhibition and seven were found as potent inhibitors of the enzyme. Compounds 2, 3, 4, 5, 6, 23, and 25 exhibited IC50 values 2.71±0.007, 11.41±0.005, 37.93±0.002, 15.19±0.004, 24.71±0.007, 17.33±0.001, and 14.2±0.002?M, respectively, as compared to standard acarbose (IC50, 38.25±0.12?M). Docking studies helped to find interactions between the enzyme and the active compounds. As a result of this study, oxindoles have been discovered as a new class of ?-glucosidase inhibitors which have not been reported earlier. PMID:24825482

Khan, Momin; Yousaf, Muhammad; Wadood, Abdul; Junaid, Muhammad; Ashraf, Muhammad; Alam, Umber; Ali, Muhammad; Arshad, Muhammad; Hussain, Zahid; Khan, Khalid Mohammed

2014-07-01

416

Design of more potent squalene synthase inhibitors with multiple activities.  

PubMed

With the increasing realization that modulating a multiplicity of targets can be an asset in the treatment of multifactorial disorders, we hereby report the synthesis and evaluation of the first compounds in which antioxidant, anti-inflammatory as well as squalene synthase (SQS) inhibitory activities are combined by design, in a series of simple molecules, extending their potential range of activities against the multifactorial disease of atherosclerosis. The activity of the initially synthesized antihyperlipidemic morpholine derivatives (1-6), in which we combined several pharmacophore moieties, was evaluated in vitro (antioxidant, inhibition of SQS and lipoxygenase) and in vivo (anti-dyslipidemic and anti-inflammatory effect). We further compared the in vitro SQS inhibitory action of these derivatives with theoretically derived molecular interactions by performing an in silico docking study using the X-ray crystal structure of human SQS. Based on low energy preferred binding modes, we designed potentially more potent SQS ligands. We proceeded with synthesizing and evaluating these new structures (7-12) in vitro and in vivo, to show that the new derivatives were significantly more active than formerly developed congeners, both as SQS inhibitors (20-70-fold increase in activity) and antioxidants (4-30-fold increase in activity). A significant correlation between experimental activity [Log(1/IC(50))] and the corresponding binding free energy (?G(b)) of the docked compounds was shown. These results, taken together, show a promising alternative and novel approach for the design and development of multifunctional antiatherosclerosis agents. PMID:20888243

Kourounakis, Angeliki P; Matralis, Alexios N; Nikitakis, Anastasios

2010-11-01

417

Potent antiviral flavone glycosides from Ficus benjamina leaves.  

PubMed

Crude ethanol extracts from Ficus benjamina leaves strongly inhibit Herpes Simplex Virus 1 and 2 (HSV-1/2) as well as Varicella Zoster Virus (VZV) cell infection in vitro. Bioassay-guided fractionation of the crude extract demonstrated that the most efficient inhibition of HSV-1 and HSV-2 was obtained with the flavonoid fraction. The present study was aimed to further isolate, purify and identify substances with potent antiviral activity from the flavonoid fraction of F. benjamina extracts. Flavonoids were collected from the leaf ethanol extracts through repeated purification procedure and HPLC analysis. The antiviral activity of each substance was then evaluated in cell culture. Three known flavone glycosides, (1) quercetin 3-O-rutinoside, (2) kaempferol 3-O-rutinoside and (3) kaempferol 3-O-robinobioside, showing highest antiviral efficiency were selected and their structure was determined by spectroscopic analyses including NMR and mass spectrometry (MS). These three flavones were highly effective against HSV-1 reaching a selectivity index (SI) of 266, 100 and 666 for compound 1, 2 and 3, respectively, while the SI of their aglycons, quercetin and kaempferol amounted only in 7.1 and 3.2, respectively. Kaempferol 3-O-robinobioside showed similar SI to that of acyclovir (ACV), the standard anti-HSV drug. Although highly effective against HSV-1 and HSV-2, these flavone glycosides did not show any significant activity against VZV. PMID:22155188

Yarmolinsky, Ludmila; Huleihel, Mahmoud; Zaccai, Michele; Ben-Shabat, Shimon

2012-03-01

418

New, potent, and selective peptidic oxytocin receptor agonists.  

PubMed

Mothers of preterm babies frequently have difficulty establishing or maintaining lactation, thought to be due to interference with the milk ejection reflex. Administration of exogenous oxytocin can produce alveolar contraction and adequate breast emptying resulting in establishment of successful lactation. The natural hormone oxytocin is not receptor-selective and may cause hyponatremia via V2 receptor mediated antidiuresis. We have designed a series of potent oxytocin analogues containing N-alkylglycines in position 7 with excellent selectivity versus the related V1a, V1b, and V2 vasopressin receptors and short half-life: agonists 31 ([2-ThiMeGly(7)]dOT), 47 (carba-6-[Phe(2),BuGly(7)]dOT), 55 (carba-6-[3-MeBzlGly(7)]dOT), and 57 (carba-1-[4-FBzlGly(7)]dOT) have EC50 values at hOTR < 0.1 nM, selectivity ratios versus related human vasopressin receptors of >2000, IC50 at hV1aR > 500 nM, and total clearance in rats in the range of 60-80 mL min(-1) kg(-1). Compound 57 (FE 202767) is currently in clinical development for the treatment of preterm mothers requiring lactation support. PMID:24874785

Wi?niewski, Kazimierz; Alagarsamy, Sudarkodi; Galyean, Robert; Tariga, Hiroe; Thompson, Dorain; Ly, Brian; Wi?niewska, Halina; Qi, Steve; Croston, Glenn; Laporte, Regent; Rivière, Pierre J-M; Schteingart, Claudio D

2014-06-26

419

Novel thiocyanato complexes with potent cytotoxic and antimicrobial properties.  

PubMed

The aim of the present study was to assess the cytotoxic and antimicrobial properties of seven new thiocyanato complexes: Ni(C(9)H(11)N(2)O)(SCN), Cu(C(9)H(11)N(2)O)(SCN), Pd(C(9)H(11)N(2)O)(SCN), Pt(C(9)H(11)N(2) O) (SCN), K[Ti(C(9)H(11)N(2)O)(SCN)(3)], Au(C(9)H(11)N(2)O)(SCN), and K[V(O)(C(9)H(11)N(2)O)(SCN)] (T(1)-T(7), respectively). All the complexes showed toxicity against brine shrimp nauplii (Artemia salina L.). The titanium-based complex, T(5), exhibited potent toxicity, with a lethal concentration 50% (the concentration of test compound that kills 50% of A. salina) value of 1.59 microg mL(-1). These new complexes also exhibited promising antibacterial and antifungal properties. A macrodilution technique was used to estimate the minimum inhibitory concentrations of the seven bioactive complexes. Minimum inhibitory concentrations were found to be 8-64 microg mL(-1) against the tested bacterial species. PMID:15563758

Hossain, M Shamim; Easmin, Sabina; Islam, M Saidul; Rashid, Mamunur

2004-12-01

420

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

PubMed Central

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

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

2013-01-01

421

Thermal conductance of a pressed Al-Al contact  

NASA Astrophysics Data System (ADS)

Thermal conductance of a screw-fastened joint between two blocks of Al-alloys has been measured. An AlMg4.5Mn-block, the end of which is cooled by liquid helium, constitutes the upper part of the sample and the contact is formed at the face surface of a cylindrical extension of that block onto which a cylinder, made of AlMgSi1, is pressed by means of a copper-nickel screw. Pressing of the contact was carried out at room temperature by applying a defined torque, M, to the fastening screw. Three samples of the same shape but with differently treated surfaces of contact (machined flat, electro-chemically polished, with gold plated contacts) were studied. The results showed that the machined flat surfaces yield the best contact and that the contact conductance (measured in the range 4.2 K to 1.8 K) of all samples increased with increasing torque. In addition to thermal measurements, a study of the electrical conductance would be very interesting to determine the different contributions of phonon and electron heat conduction by means of the Wiedemann-Franz law. The work is useful for the GIRL (German Infra-Red Laboratory) space experiment.

Wanner, M.

1981-01-01

422

Microdroplet evaporation with a forced pinned contact line.  

PubMed

Experimental and numerical investigations of water microdroplet evaporation on heated, laser patterned polymer substrates are reported. The study is focused on both (i) controlling a droplet's contact line dynamics during evaporation to identifying how the contact line influences evaporative heat transfer and (ii) validating numerical simulations with experimental data. Droplets are formed on the polymer surface using a bottom-up methodology, where a computer-controlled syringe pump feeds water through a 200 ?m diameter fluid channel within the heated polymer substrate. This methodology facilitates precise control of the droplet's growth rate, size, and inlet temperature. In addition to this microchannel supply line, the substrate surfaces are laser patterned with a moatlike trench around the fluid-channel outlet, adding additional control of the droplet's contact line motion, area, and contact angle. In comparison to evaporation on a nonpatterned polymer surface, the laser patterned trench increases contact line pinning time by ?60% of the droplet's lifetime. Numerical simulations of diffusion controlled evaporation are compared the experimental data with a pinned contact line. These diffusion based simulations consistently over predict the droplet's evaporation rate. In efforts to improve this model, a temperature distribution along the droplet's liquid-vapor interface is imposed to account for the concentration distribution of saturated vapor along the interface, which yields improved predictions within 2-4% of the experimental data throughout the droplet's lifetime on heated substrates. PMID:25102248

Gleason, Kevin; Putnam, Shawn A

2014-09-01

423

Identification of GNE477, a potent and efficacious dual PI3K\\/mTOR inhibitor  

Microsoft Academic Search

Efforts to identify potent small molecule inhibitors of PI3 kinase and mTOR led to the discovery of the exceptionally potent 6-aryl morpholino thienopyrimidine 6. In an effort to reduce the melting point in analogs of 6, the thienopyrimidine was modified by the addition of a methyl group to disrupt planarity. This modification resulted in a general improvement in in vivo

Timothy P. Heffron; Megan Berry; Georgette Castanedo; Christine Chang; Irina Chuckowree; Jennafer Dotson; Adrian Folkes; Janet Gunzner; John D. Lesnick; Cristina Lewis; Simon Mathieu; Jim Nonomiya; Alan Olivero; Jodie Pang; David Peterson; Laurent Salphati; Deepak Sampath; Steve Sideris; Daniel P. Sutherlin; Vickie Tsui; Nan Chi Wan; Shumei Wang; Susan Wong; Bing-yan Zhu

2010-01-01

424

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

425

ABT-378, a Highly Potent Inhibitor of the Human Immunodeficiency Virus Protease  

Microsoft Academic Search

The valine at position 82 (Val 82) in the active site of the human immunodeficiency virus (HIV) protease mutates in response to therapy with the protease inhibitor ritonavir. By using the X-ray crystal structure of the complex of HIV protease and ritonavir, the potent protease inhibitor ABT-378, which has a diminished interaction with Val 82, was designed. ABT-378 potently inhibited

HING L. SHAM; DALE J. KEMPF; AKHTERUZAMMEN MOLLA; KENNAN C. MARSH; GONDI N. KUMAR; CHIH-MING CHEN; WARREN KATI; KENT STEWART; RITU LAL; ANN HSU; DAVID BETEBENNER; MARINA KORNEYEVA; SUDTHIDA VASAVANONDA; EDITH MCDONALD; AYDA SALDIVAR; NORM WIDEBURG; XIAOQI CHEN; PING NIU; CHANG PARK; VENKATA JAYANTI; BRIAN GRABOWSKI; G. RICHARD GRANNEMAN; EUGENE SUN; ANTHONY J. JAPOUR; JOHN M. LEONARD; JACOB J. PLATTNER; DANIEL W. NORBECK

1998-01-01

426

A Class of Potent Antimalarials and Their Specific Accumulation in Infected Erythrocytes  

Microsoft Academic Search

During asexual development within erythrocytes, malaria parasites synthesize considerable amounts of membrane. This activity provides an attractive target for chemotherapy because it is absent from mature erythrocytes. We found that compounds that inhibit phosphatidylcholine biosynthesis de novo from choline were potent antimalarial drugs. The lead compound, G25, potently inhibited in vitro growth of the human malaria parasites Plasmodium falciparum and

Kai Wengelnik; Valérie Vidal; Marie L. Ancelin; Anne-Marie Cathiard; Jean Louis Morgat; Clemens H. Kocken; Michèle Calas; Socrates Herrera; Alan W. Thomas; Henri J. Vial

2002-01-01

427

Structure based design of a series of potent and selective non peptidic PTP-1B inhibitors.  

PubMed

A series of benzotriazole phenyldifluoromethylphosphonic acids were found to be potent PTP-1B inhibitors. Molecular modeling on the X-ray crystal structure of the lead structure led to the design of potent PTP-1B inhibitors that show moderate selectivity against TC-PTP, a very closely related protein tyrosine phosphatase. PMID:15013020

Lau, Cheuk K; Bayly, Christopher I; Gauthier, Jacques Yves; Li, Chun Sing; Therien, Michel; Asante-Appiah, Ernest; Cromlish, Wanda; Boie, Yves; Forghani, Farnaz; Desmarais, Sylvie; Wang, Qingping; Skorey, Kathryn; Waddleton, Deena; Payette, Paul; Ramachandran, Chidambaram; Kennedy, Brian P; Scapin, Giovana

2004-02-23

428

Structure based design of a series of potent and selective non peptidic PTP1B inhibitors  

Microsoft Academic Search

A series of benzotriazole phenyldifluoromethylphosphonic acids were found to be potent PTP-1B inhibitors. Molecular modeling on the X-ray crystal structure of the lead structure led to the design of potent PTP-1B inhibitors that show moderate selectivity against TC-PTP, a very closely related protein tyrosine phosphatase.

Cheuk K. Lau; Christopher I. Bayly; Jacques Yves Gauthier; Chun Sing Li; Michel Therien; Ernest Asante-Appiah; Wanda Cromlish; Yves Boie; Farnaz Forghani; Sylvie Desmarais; Qingping Wang; Kathryn Skorey; Deena Waddleton; Paul Payette; Chidambaram Ramachandran; Brian P. Kennedy; Giovana Scapin

2004-01-01

429

Contact microscopy with synchrotron radiation  

SciTech Connect

Soft x-ray contact microscopy with synchrotron radiation offers the biologist and especially the microscopist, a way to morphologically study specimens that could not be imaged by conventional TEM, STEM or SEM methods (i.e. hydrated samples, samples easily damaged by an electron beam, electron dense samples, thick specimens, unstained low contrast specimens) at spatial resolutions approaching those of the TEM, with the additional possibility to obtain compositional (elemental) information about the sample as well. Although flash x-ray sources offer faster exposure times, synchrotron radiation provides a highly collimated, intense radiation that can be tuned to select specific discrete ranges of x-ray wavelengths or specific individual wavelengths which optimize imaging or microanalysis of a specific sample. This paper presents an overview of the applications of x-ray contact microscopy to biological research and some current research results using monochromatic synchrotron radiation to image biological samples. 24 refs., 10 figs.

Panessa-Warren, B.J.

1985-10-01

430

Contact inhibition in tissue culture  

Microsoft Academic Search

Conclusions  Contact inhibition of movement is here defined simply as the stopping of the continued locomotion of a cell in the direction\\u000a which has produced a collision with another cell; so that one cell does not use another as a substratum. Amongst fibroblasts\\u000a and epithelial cells this inhibition seems to be brought about by a mechanism which it is suggested consists

M. Abercrombie

1970-01-01

431

New Low Contact Resistance Electrode  

Microsoft Academic Search

STUDY was made of the contact resistance developed at a ferrite-electrode interface using for comparative purposes a variety of different electrode materials and methods of application. In this study individual samples measuring 0.565 in.XO.31O in. XO.065 in. were sectioned from a high-density homogeneous nickel ferrite ceramic body. Samples were cleaned in acetone immedi­ ately prior to application of electrodes. Measured

S. S. Flaschen; L. G. van Uitert

1956-01-01

432

Allergic Contact Dermatitis: Rubber Allergies  

Microsoft Academic Search

\\u000a Latex (rubber) allergy is a growing health concern among medical and nonmedical fields. Common occupational exposures include,\\u000a health care and food industry workers using disposable gloves, latex industry employees, and car ­factory workers assembling\\u000a rubber details. Additionally, high-risk groups include children with spina bifida or spinal dysraphism. Risk factors for latex\\u000a allergic ­contact dermatitis (ACD) include skin damage allowing increased

Peter Burke; Howard I. Maibach

433

HR Student Forms Checklist Undergraduate/Graduate CSM Student Employees  

E-print Network

-Disclosure Form EEO Individuals with Disabilities & Veterans Voluntary Self-Disclosure Form Emergency Contact for Nonimmigrant (F-1) Student Status - for Academic and Language Students (I-20), Certificate of Eligibility

434

Method for manufacturing 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)

1988-11-08

435

Contact structure for use in catalytic distillation  

DOEpatents

A method is described for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor, contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column. 7 figs.

Jones, E.M. Jr.

1984-03-27

436

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

437

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

Marinkovic, Aleksandar; Liu, Fei

2013-01-01

438

Potent and specific antitumor effect of CEA-targeted photoimmunotherapy.  

PubMed

Conventional photodynamic therapy (PDT) for cancer is limited by the insufficient efficacy and specificity of photosensitizers. We herein describe a highly effective and selective tumor-targeted PDT using a near-infrared (NIR) photosensitizer, IRDye700DX, conjugated to a human monoclonal antibody (Ab) specific for carcinoembryonic antigen (CEA). The antitumor effects of this Ab-assisted PDT, called photoimmunotherapy (PIT), were investigated in vitro and in vivo. The Ab-IRDye conjugate induced potent cytotoxicity against CEA-positive tumor cells after NIR-irradiation, whereas CEA-negative cells were not affected at all, even in the presence of excess photoimmunoconjugate. We found an equivalent phototoxicity and a predominant plasma membrane localization of Ab-IRDye after both one and six hours of incubation. Either no or little caspase activation and membrane peroxidation were observed in PIT-treated cells and a panel of scavengers for reactive oxygen species showed only partial inhibition of the phototoxic effect. Strikingly, Ab-IRDye retained significant phototoxicity even under hypoxia. We established a xenograft model, which allowed us to sensitively investigate the therapeutic efficacy of PIT by non-invasive bioluminescence imaging. Luciferase-expressing MKN-45-luc human gastric carcinoma cells were subcutaneously implanted into both flanks of nude mice. NIR-irradiation was performed for only the tumor on one side. In vivo imaging and measurement of the tumor size revealed that a single PIT treatment, with intraperitoneal administration of Ab-IRDye and subsequent NIR-irradiation, caused rapid cell death and significant inhibition of tumor growth, but only on the irradiated side. Together, these data suggest that Ab-IRDye-mediated PIT has great potential as an anticancer therapeutics targeting CEA-positive tumors. PMID:24740257

Shirasu, Naoto; Yamada, Hiromi; Shibaguchi, Hirotomo; Kuroki, Motomu; Kuroki, Masahide

2014-12-01

439

Direct-Write Contacts: Metallization and Contact Formation; Preprint  

SciTech Connect

Using direct-write approaches in photovoltaics for metallization and contact formation can significantly reduce the cost per watt of producing photovoltaic devices. Inks have been developed for various materials, such as Ag, Cu, Ni and Al, which can be used to inkjet print metallizations for various kinds of photovoltaic devices. Use of these inks results in metallization with resistivities close to those of bulk materials. By means of inkjet printing a metallization grid can be printed with better resolution, i.e. smaller lines, than screen-printing. Also inks have been developed to deposit transparent conductive oxide films by means of ultrasonic spraying.

van Hest, M. F. A. M.; Curtis, C. J.; Miedaner, A.; Pasquarelli, R. M.; Kaydonova, T.; Hersh, P.; Ginley, D. S.

2008-05-01

440

Humidity-induced room-temperature decomposition of Au contacted indium phosphide  

NASA Technical Reports Server (NTRS)

It has been found that Au-contacted InP is chemically unstable at room temperature in a humid ambient due to the leaching action of indium nitrate islands that continually remove In from the contact metallization and thus, in effect, from the Inp substrate. While similar appearing islands form on Au-contacted GaAs, that system appears to be stable since leaching of the group III element does not take place.

Fatemi, Navid S.; Weizer, Victor G.

1990-01-01

441

Activation of the human contact system on neutrophil extracellular traps.  

PubMed

Pattern recognition is an integral part of the innate immune system. The human contact system has been shown to interact with the surface of many bacterial and fungal pathogens, and once activated leads to the generation of antimicrobial peptides and the proinflammatory mediator bradykinin. Here we show that apart from these surfaces also neutrophil extracellular traps (NETs) provide a surface that allows the binding and activation of the contact system. In addition, we present evidence that M1 protein, a streptococcal surface protein, in concert with human fibrinogen triggers polymorphonuclear neutrophils to form NETs. PMID:20375580

Oehmcke, Sonja; Mörgelin, Matthias; Herwald, Heiko

2009-01-01

442

Soft electrical contacts for conductivity measurements of molecularly modified surfaces  

NASA Astrophysics Data System (ADS)

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 chemically modified silicon surfaces with organic molecules belonging to ethynylbenzene (EBZ) series. The measured conductivity is found to be very sensitive to the dipole moment of bonded organic molecules.

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

2009-01-01

443

75 FR 6032 - National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation...  

Federal Register 2010, 2011, 2012, 2013

...OMB Control No. 3090-0278] National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation Survey AGENCY...collection requirement regarding the National Contact Center customer evaluation survey. A...

2010-02-05

444

78 FR 30303 - National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation...  

Federal Register 2010, 2011, 2012, 2013

...Control No. 3090-0278; Docket 2012-0001; Sequence 19] National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation Survey AGENCY: Contact Center Services, Federal Citizen Information Center, Office...

2013-05-22

445

78 FR 14549 - National Contact Center; Information Collection; National Contact Center Customer Evaluation Survey  

Federal Register 2010, 2011, 2012, 2013

...Control No. 3090-0278; Docket 2012-0001; Sequence 19] National Contact Center; Information Collection; National Contact Center Customer Evaluation Survey AGENCY: Contact Center Services, Federal Citizen Information Center, Office of...

2013-03-06

446

Potent Inhibitory Effect of ?-Tocopherol on Prostate Cancer Cells Cultured in Vitro and Grown As Xenograft Tumors in Vivo.  

PubMed

In the present study, the effects of ?-tocopherol (?-T) on growth and apoptosis of human prostate cancer cells were determined and compared with that of ?-tocopherol (?-T), a commonly used form of vitamin E. Treatment of human prostate cancer cells with ?-T resulted in strong growth inhibition and apoptosis stimulation, while the effects of ?-T were modest. The strong effects of ?-T on the cells were associated with suppression of androgen receptor (AR) activity and decreased level of prostate specific antigen (PSA) that is a downstream target of the AR signaling. In the in vivo study, we found that ?-T had a more potent inhibitory effect on the formation and growth of prostate xenograft tumors than that of ?-T. Moreover, ?-T inhibited proliferation and stimulated apoptosis in the tumors. The present study identified ?-T as a better form of vitamin E than ?-T for future clinical studies of prostate cancer prevention. PMID:25322450

Huang, Huarong; He, Yan; Cui, Xiao-Xing; Goodin, Susan; Wang, Hong; Du, Zhi Yun; Li, Dongli; Zhang, Kun; Tony Kong, Ah-Ng; DiPaola, Robert S; Yang, Chung S; Conney, Allan H; Zheng, Xi

2014-11-01

447

Low frequency electrical noise across contacts between a normal conductor and superconducting bulk YBa2Cu3O7  

Microsoft Academic Search

Virtually every device that makes use of the new ceramic superconductors will need normal conductor to supercondutor contacts. The current-voltage and electrical noise characteristics of these contacts could be become important design considerations. I-V and low frequency electrical noise measurements are presented on contacts between a normal conductor and superconducting polycrystalline YBa2Cu3O7. The contacts were formed by first sputtering gold

J. Hall; T. M. Chen

1990-01-01

448

Low frequency electrical noise across contacts between a normal conductor and superconducting bulk YBa2Cu3O7  

Microsoft Academic Search

Virtually every device that makes use of the new ceramic superconductors will need normal conductor to superconductor contacts. The current-voltage and electrical noise characteristics of these contacts could become important design considerations. I-V and low frequency electrical noise measurements are presented on contacts between a normal conductor and superconducting polycrystalline YBa2Cu3O7. The contacts were formed by first sputtering gold palladium

J. Hall; T. M. Chen

1991-01-01

449

Contact dermatitis and workforce economics.  

PubMed

The roots of education in patch testing begin with Jadassohn and have been passed down through generations of dermatologists through didactic teachings and mentoring. Currently, we are faced with workforce economics tipping the balance of dermatology toward cosmetic and surgical practices. This imbalance is easily found in the subspecialty of contact dermatitis, where the current demand for patch test services is on the rise and the number of new dermatology-based patch test providers cannot keep up with the current demand. Steps are being made to remedy this discrepancy through societies and fellowships, yet the question remains: were the steps in time and were they big enough? PMID:16908402

Jacob, Sharon E; Steele, Tace

2006-06-01

450

Thermal Conductances Of Metal Contacts  

NASA Technical Reports Server (NTRS)

Report presents results of measurements of thermal conductances of aluminum and stainless-steel contacts at temperatures from 1.6 to 6.0 K. Measurement apparatus includes gearmotor assembly connected to rocker arm by music wire to load sample pair with forces up to 670 N. Heater placed above upper sample. Germanium resistance thermometers in upper and lower samples measured temperature difference across interface over range of heater powers from 0.1 to 10.0 mW. The thermal conductance calculated from temperature difference. Measurements provide data for prediction of thermal conductances of bolted joints in cryogenic infrared instruments.

Salerno, L. J.; Kittel, P.; Scherkenbach, F. E.; Spivak, A. L.

1988-01-01

451

Gradient-index contact lens  

NASA Astrophysics Data System (ADS)

A gradient-index (GRIN) contact lens (CL) is proposed to decrease spherical aberration and to increase the diopter. A plastic radial GRIN rod was successfully obtained by using the vapor-phase diffusion copolymerization technique. The resulting index distribution of the GRIN rod was almost parabolic against the distance from the center axis, and the Delta n value was -0.030. The GRIN CL was prepared by grinding and polishing the rod. It is theoretically and experimentally concluded that using the radial GRIN material can significantly improve the optical properties of CL's.

Koike, Yasuhiro; Asakawa, Akihiko; Wu, Shang Pin; Nihei, Eisuke

1995-08-01

452

Frictionless contact of aircraft tires  

NASA Technical Reports Server (NTRS)

A computational procedure for the solution of frictionless contact problems of spacecraft tires was developed using a two-dimensional laminated anisotropic shell theory incorporating the effects of variations in material and geometric parameters, transverse shear deformation, and geometric nonlinearities to model the nose-gear tire of a space shuttle. Numerical results are presented for the case when the nose-gear tire is subjected to inflation pressure and pressed against a rigid pavement. The results are compared with experimental results obtained at NASA Langley, demonstrating a high accuracy of the model and the effectiveness of the computational procedure.

Kim, Kyun O.; Tanner, John A.; Noor, Ahmed K.

1989-01-01

453

Effect of flow field and geometry on the dynamic contact angle A. V. Lukyanov1  

E-print Network

contact angle formed by an advancing liquid-gas interface with a solid substrate depends on the flow field the interfaces, which can be influenced by the flow field, one can use the overall flow conditions- fect the flow field in the vicinity of the contact line? Since the influence of the flow field

Lukyanov, Alex

454

Using Contact Work in Interactions with Adults with Learning Disabilities and Autistic Spectrum Disorders  

ERIC Educational Resources Information Center

This article describes a project about using contact work with people with learning disabilities and autistic spectrum disorder. People with learning disabilities and additional autistic spectrum disorder are at risk of becoming socially isolated because of their difficulties in interacting with others. Contact work is a form of Pre-Therapy, which…

Brooks, Sharon; Paterson, Gail

2011-01-01

455

SINGLE POINT CONTACT MEASUREMENTS OF MECHANICAL RESONANCES C. P. Hsieh and B. T. Khuri-Yakub  

E-print Network

and to the presence of surface defects. INTRODUCTION Ceramic material retains high strength under high temperature spheres at both low and high frequencies. Resonances are generated by forming a one-point Hertzian contactSINGLE POINT CONTACT MEASUREMENTS OF MECHANICAL RESONANCES C. P. Hsieh and B. T. Khuri-Yakub Edward

Khuri-Yakub, Butrus T. "Pierre"

456

Mechanisms of microstructural damage during rolling contact fatigue of bearing steels  

E-print Network

.2 Stress state during rolling contacts . . . . . . . . . . . . . . . . . . . . . . 6 2.2.1 Hertzian elastic contact theory . . . . . . . . . . . . . . . . . . . . . 8 2.2.2 Cyclic plasticity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2... forms of the damage. They are so-called because of their different etching behaviour with respect to the unaffected region. Such damage stems from microstructural changes such as carbide coarsening/dissolution as well as the formation of cellular...

Kang, JeeHyun

2014-04-08

457

The Russians Are Coming, the Russians are Dead: Myth and Historical Consciousness in Two Contact Narratives.  

ERIC Educational Resources Information Center

This research paper examines hidden cultural patterns establishing the expression of historical thought in Native Alaskan narratives which describe first contact with Russians. Historical consciousness in oral contact stories is always mythic in form, as well as in content. Native American oral cultures understood new events by "troping," or…

Ruppert, James

458

Numerical study of single bubbles with dynamic contact angle during nucleate pool boiling  

E-print Network

Numerical study of single bubbles with dynamic contact angle during nucleate pool boiling Abhijit form 27 June 2006 Available online 12 September 2006 Abstract Nucleate pool boiling is typically. All rights reserved. Keywords: Bubble; Contact angle; Boiling 1. Introduction Bubbles nucleate from

Kandlikar, Satish

459

Ohmic contacting schemes to gallium arsenide devices  

NASA Astrophysics Data System (ADS)

The goal of this project was to design ohmic contacting schemes to gallium arsenide that would sustain 400C for 1 hour and 600C for 15 minutes without significant degradation. Our approach uses a generic contacting scheme calling for two thin-film layers between the semiconducting substrate and the metal overlayer: (1) a contacting layer adjacent to the semiconductor that determines the electrical properties of the contact, and (2) a diffusion barrier layer adjacent to the metal overlayer that assures the thermal stability of the contact. A contact designed according to this scheme (silver overlayer, pure tungsten or tungsten-nitrogen layer as the diffusion barrier, and a magnesium-doped platinum film for the contacting layer to p-type gallium arsenide) changes little upon annealing at 550C for 5 hours. The contact resistivity is on the order of 1E-3 ohm sq cm or less.

1987-08-01

460

Pulsed Current Static Electrical Contact Experiment  

Microsoft Academic Search

Railguns involve both static and sliding electrical contacts, which must transmit the large transient electrical currents necessary to impart high forces onto a projectile for acceleration to hypervelocity. Static electrical contacts between metals initially take place through small asperities, or \\

Harry N. Jones; Jesse M. Neri; Craig N. Boyer; Khershed P. Cooper; Robert A. Meger

2007-01-01

461

Posaconazole Is a Potent Inhibitor of Sterol 14?-Demethylation in Yeasts and Molds  

PubMed Central

Posaconazole (POS; SCH 56592) is a novel triazole that is active against a wide variety of fungi, including fluconazole-resistant Candida albicans isolates and fungi that are inherently less susceptible to approved azoles, such as Candida glabrata. In this study, we compared the effects of POS, itraconazole (ITZ), fluconazole (FLZ), and voriconazole (VOR) on sterol biosynthesis in strains of C. albicans (both azole-sensitive and azole-resistant strains), C. glabrata, Aspergillus fumigatus, and Aspergillus flavus. Following exposure to azoles, nonsaponifiable sterols were extracted and resolved by liquid chromatography and sterol identity was confirmed by mass spectroscopy. Ergosterol was the major sterol in all but one of the strains; C. glabrata strain C110 synthesized an unusual sterol in place of ergosterol. Exposure to POS led to a decrease in the total sterol content of all the strains tested. The decrease was accompanied by the accumulation of 14?-methylated sterols, supporting the contention that POS inhibits the cytochrome P450 14?-demethylase enzyme. The degree of sterol inhibition was dependent on both dose and the susceptibility of the strain tested. POS retained activity against C. albicans isolates with mutated forms of the 14?-demethylase that rendered these strains resistant to FLZ, ITZ, and VOR. In addition, POS was a more potent inhibitor of sterol synthesis in A. fumigatus and A. flavus than either ITZ or VOR. PMID:15388421

Munayyer, Hanan K.; Mann, Paul A.; Chau, Andrew S.; Yarosh-Tomaine, Taisa; Greene, Jonathan R.; Hare, Roberta S.; Heimark, Larry; Palermo, Robert E.; Loebenberg, David; McNicholas, Paul M.

2004-01-01

462

Discovery of Q203, a potent clinical candidate for the treatment of tuberculosis.  

PubMed

New therapeutic strategies are needed to combat the tuberculosis pandemic and the spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) forms of the disease, which remain a serious public health challenge worldwide. The most urgent clinical need is to discover potent agents capable of reducing the duration of MDR and XDR tuberculosis therapy with a success rate comparable to that of current therapies for drug-susceptible tuberculosis. The last decade has seen the discovery of new agent classes for the management of tuberculosis, several of which are currently in clinical trials. However, given the high attrition rate of drug candidates during clinical development and the emergence of drug resistance, the discovery of additional clinical candidates is clearly needed. Here, we report on a promising class of imidazopyridine amide (IPA) compounds that block Mycobacterium tuberculosis growth by targeting the respiratory cytochrome bc1 complex. The optimized IPA compound Q203 inhibited the growth of MDR and XDR M. tuberculosis clinical isolates in culture broth medium in the low nanomolar range and was efficacious in a mouse model of tuberculosis at a dose less than 1 mg per kg body weight, which highlights the potency of this compound. In addition, Q203 displays pharmacokinetic and safety profiles compatible with once-daily dosing. Together, our data indicate that Q203 is a promising new clinical candidate for the treatment of tuberculosis. PMID:23913123

Pethe, Kevin; Bifani, Pablo; Jang, Jichan; Kang, Sunhee; Park, Seijin; Ahn, Sujin; Jiricek, Jan; Jung, Juyoung; Jeon, Hee Kyoung; Cechetto, Jonathan; Christophe, Thierry; Lee, Honggun; Kempf, Marie; Jackson, Mary; Lenaerts, Anne J; Pham, Ha; Jones, Victoria; Seo, Min Jung; Kim, Young Mi; Seo, Mooyoung; Seo, Jeong Jea; Park, Dongsik; Ko, Yoonae; Choi, Inhee; Kim, Ryangyeo; Kim, Se Yeon; Lim, SeungBin; Yim, Seung-Ae; Nam, Jiyoun; Kang, Hwankyu; Kwon, Haejin; Oh, Chun-Taek; Cho, Yoojin; Jang, Yunhee; Kim, Junghwan; Chua, Adeline; Tan, Bee Huat; Nanjundappa, Mahesh B; Rao, Srinivasa P S; Barnes, Whitney S; Wintjens, René; Walker, John R; Alonso, Sylvie; Lee, Saeyeon; Kim, Jungjun; Oh, Soohyun; Oh, Taegwon; Nehrbass, Ulf; Han, Sung-Jun; No, Zaesung; Lee, Jinhwa; Brodin, Priscille; Cho, Sang-Nae; Nam, Kiyean; Kim, Jaeseung

2013-09-01

463

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

464

Phenothiazine is a potent inhibitor of prostaglandin E2 production by Candida albicans biofilms.  

PubMed

Candida albicans is an important opportunistic yeast pathogen of humans and has the ability to form drug-resistant biofilms, with increased expression of multidrug ATP-binding cassette (ABC) transporters. These biofilms are also capable of secreting immune-modulating prostaglandin E2 (PGE2 ) from host-derived arachidonic acid (AA). Phenothiazine, an aromatic amine, and its derivatives display broad activity as inhibitors and antioxidants. These compounds have fungistatic and fungicidal activity against planktonic C. albicans and can inhibit ABC transporters of C. albicans. This study investigated the effect of phenothiazine on biofilm formation, ABC transporters and PGE2 production by C. albicans. This was carried out by growing C. albicans biofilms in the presence of AA and phenothiazine and measuring the biomass as well as reduction of 2,3-bis(2-methoxy-4-nitro-5-sulphophenyl)-5[(phenylamino) carbonyl]-2H tetrazolium hydroxide. The effect on ABC transporters was determined by rhodamine 6G efflux, and the concentration of PGE2 was determined by a monoclonal PGE2 enzyme-linked immunosorbent assay and LC/MS/MS. Our results indicate that phenothiazine can cause a reduction in both the metabolic activity and biomass of C. albicans biofilms, without affecting biofilm morphology or ABC transporters. However, it is a potent inhibitor of PGE2 production by C. albicans biofilms. PMID:24103090

Ells, Ruan; Kemp, Gabré; Albertyn, Jacobus; Kock, Johan L F; Pohl, Carolina H

2013-12-01

465

Rapid discovery of potent siRNA-containing lipid nanoparticles enabled by controlled microfluidic formulation.  

PubMed

The discovery of potent new materials for in vivo delivery of nucleic acids depends upon successful formulation of the active molecules into a dosage form suitable for the physiological environment. Because of the inefficiencies of current formulation methods, materials are usually first evaluated for in vitro delivery efficacy as simple ionic complexes with the nucleic acids (lipoplexes). The predictive value of such assays, however, has never been systematically studied. Here, for the first time, by developing a microfluidic method that allowed the rapid preparation of high-quality siRNA-containing lipid nanoparticles (LNPs) for a large number of materials, we have shown that gene silencing assays employing lipoplexes result in a high rate of false negatives (~90%) that can largely be avoided through formulation. Seven novel materials with in vivo gene silencing potencies of >90% at a dose of 1.0 mg/kg in mice were discovered. This method will facilitate the discovery of next-generation reagents for LNP-mediated nucleic acid delivery. PMID:22475086

Chen, Delai; Love, Kevin T; Chen, Yi; Eltoukhy, Ahmed A; Kastrup, Christian; Sahay, Gaurav; Jeon, Alvin; Dong, Yizhou; Whitehead, Kathryn A; Anderson, Daniel G

2012-04-25

466

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

467

Crystal Structure of HIV-1 Primary Receptor CD4 i Complex with a Potent Antiviral Antibody  

SciTech Connect

Ibalizumab is a humanized, anti-CD4 monoclonal antibody. It potently blocks HIV-1 infection and targets an epitope in the second domain of CD4 without interfering with immune functions mediated by interaction of CD4 with major histocompatibility complex (MHC) class II molecules. We report here the crystal structure of ibalizumab Fab fragment in complex with the first two domains (D1-D2) of CD4 at 2.2 {angstrom} resolution. Ibalizumab grips CD4 primarily by the BC-loop (residues 121125) of D2, sitting on the opposite side of gp120 and MHC-II binding sites. No major conformational change in CD4 accompanies binding to ibalizumab. Both monovalent and bivalent forms of ibalizumab effectively block viral infection, suggesting that it does not need to crosslink CD4 to exert antiviral activity. While gp120-induced structural rearrangements in CD4 are probably minimal, CD4 structural rigidity is dispensable for ibalizumab inhibition. These results could guide CD4-based immunogen design and lead to a better understanding of HIV-1 entry.

Freeman, M.M.; Hong, X.; Seaman, M.S.; Rits-Vollock, S.p Kao, C.Y.; Ho, D.D.; Chen, B.

2010-06-18

468

Potent anticancer activity of cystine-based dipeptides and their interaction with serum albumins  

PubMed Central

Background Cancer is a severe threat to the human society. In the scientific community worldwide cancer remains a big challenge as there are no remedies as of now. Cancer is quite complicated as it involves multiple signalling pathways and it may be caused by genetic disorders. Various natural products and synthetic molecules have been designed to prevent cell proliferation. Peptide-based anticancer drugs, however, are not explored properly. Though peptides have their inherent proteolytic instability, they could act as anticancer agents. Results In this present communication a suitably protected cystine based dipeptide and its deprotected form have been synthesized. Potent anticancer activities were confirmed by MTT assay (a laboratory test and a standard colorimetric assay, which measures changes in colour, for measuring cellular proliferation and phase contrast images. The IC50 value, a measure of the effectiveness of a compound in inhibiting biological or biochemical function, of these compounds ranges in the sub-micromolar level. The binding interactions with serum albumins (HSA and BSA) were performed with all these molecules and all of them show very strong binding at sub-micromolar concentration. Conclusions This study suggested that the cystine-based dipeptides were potential anticancer agents. These peptides also showed very good binding with major carrier proteins of blood, the serum albumins. We are currently working on determining the detailed mechanism of anticancer activity of these molecules. PMID:23705891

2013-01-01

469

Fabrication of highly stable configurable metal quantum point contacts.  

PubMed

Metal quantum point contacts (MQPCs), with dimensions comparable to the de Broglie wavelength of conducting electrons, reveal ballistic transport of electrons and quantized conductance in units of G0=2e(2)/h. While these contacts hold great promise for applications such as coherent controlled devices and atomic switches, their realization is mainly based on the scanning tunneling microscope (STM) and mechanically controlled break junction (MCBJ), which cannot be integrated into electronic circuits. MQPCs produced by these techniques have also limited stability at room temperature. Here we report on a new method to form MQPCs with quantized conductance values in the range of 1-4G0. The contacts appear to be stable at room temperature for hours and can be deterministically switched between conductance values, or reform in case they break, using voltage pulses. The method enables us to integrate MQPCs within nanoscale circuits to fully harness their unique advantages. PMID:18954127

Ittah, Naomi; Yutsis, Ilan; Selzer, Yoram

2008-11-01

470

Contact Pressure Measurement System in Cross Wedge Rolling  

NASA Astrophysics Data System (ADS)

In the cross wedge rolling process (CWR), plastic deformation is geared by a driving torque transmitted by friction on die surface. Friction plays a role which has to be further identified in this metal forming process. The local contact pressure between a cylindrical billet and flat dies seems to be a relevant parameter to characterize the severe contact conditions during the rolling. This paper deals with an experimental measurement technology, which has been designed and implemented on a semi-industrial CWR test bench with plate configuration. This measurement system using pin and piezoelectric sensor is presented, with an analysis of the system operation and design detail. Characterization of systematic error and calibration tests are then explained. Additional tests performed on hot steel preforms allow to check the ability of the contact pressure measurement system to resist under severe operating conditions. Realistic results for varying temperatures are then discussed.

Mangin, Philippe; Langlois, Laurent; Bigot, Régis

2011-01-01

471

Intrachain Contact Dynamics in Unfolded Cytochrome cb562  

PubMed Central

We have investigated intrachain contact dynamics in unfolded cytochrome cb562 by monitoring heme quenching of excited ruthenium photosensitizers covalently bound to residues along the polypeptide. Intrachain diffusion for chemically denatured proteins proceeds on the microsecond timescale with an upper limit of 0.1 ?s. The rate constants exhibit a power-law dependence on the number of peptide bonds between the heme and Ru complex. The power-law exponent of ?1.5 is consistent with theoretical models for freely jointed Gaussian chains, but its magnitude is smaller than that reported for several synthetic polypeptides. Contact formation within a stable loop was examined in a His63-heme ligated form of the protein under denaturing conditions. Loop formation accelerated contact kinetics for the Ru66 labeling site, owing to reduction in the length of the peptide separating redox sites. For other labeling sites within the stable loop, quenching rates were modestly reduced compared to the open chain polymer. PMID:23992117

Ford, Nicole D. Bouley; Shin, Dong-Woo; Gray, Harry B.; Winkler, Jay R.

2013-01-01

472