Sample records for s-methylidene agents preparation

  1. A DFT Study of Tungsten-Methylidene Formation on a W/ZSM-5 Zeolite: The Metathesis Active Site.

    PubMed

    Maihom, Thana; Probst, Michael; Limtrakul, Jumras

    2015-10-26

    Tungsten-methylidene formation from ethene on either the W(IV) , W(V) , or W(VI) active sites of a W/ZSM-5 zeolite is investigated by using the M06-L functional. The reaction is assumed to proceed in two steps; the first step is the [2+2] cycloaddition between ethene and the W-O active site to form an oxametallacycle intermediate. The intermediate is then decomposed to produce the W-methylidene active site from the metathesis reaction. The overall activation barrier of the reaction on W(VI) (27.3 kcal mol(-1) ) is considerably lower than the ones for W(IV) and W(V) (69.4 and 37.1 kcal mol(-1) , respectively). Moreover, the reaction involving the W(VI) site also stabilizes intermediates and products to a larger extent than the ones on the W(IV) and W(V) sites. As a result, we have demonstrated that the reaction of the W-methylidene metathesis active site is both kinetically and thermodynamically favored to occur on the W(VI) active site of the zeolite. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Synthesis and solid-state characterisation of 4-substituted methylidene oxindoles

    PubMed Central

    2013-01-01

    Background 4-substituted methylidene oxindoles are pharmacologically important. Detailed analysis and comparison of all the interactions present in crystal structures is necessary to understand how these structures arise. The XPac procedure allows comparison of complete crystal structures of related families of compounds to identify assemblies that are mainly the result of close-packing as well as networks of directed interactions. Results Five 4-substituted methylidene oxindoles have been synthesized by the Knoevenagel condensation of oxindole with para-substituted aromatic aldehydes and were characterized in the solid state by x-ray crystallography. Hence, the structures of (3E)-3-(4-Bromobenzylidene)-1,3-dihydro-2H-indol-2-one, 3a, (3E)-3-(4-Chlorobenzylidene)-1,3-dihydro-2H-indol-2-one, 3b, (3E)-3-(4-Methoxybenzylidene)-1,3-dihydro-2H-indol-2-one, 3c, (3E)-3-(4-Methylbenzylidene)-1,3-dihydro-2H-indol-2-one, 3d and (3E)-3-(4-Nitrobenzylidene)-1,3-dihydro-2H-indol-2-one, 3e, were elucidated using single crystal X-ray crystallography. Conclusions A hydrogen bonded dimer molecular assembly or supramolecular construct was identified in all the crystal structures examined along with a further four 1D supramolecular constructs which were common to at least two of the family of structures studied. The 1D supramolecular constructs indicate that once the obvious strong interaction is satisfied to form hydrogen bonded dimer it is the conventionally weaker interactions, such as steric bulk and edge-to-face interactions which compete to influence the final structure formation. PMID:24517531

  3. Molecular docking, vibrational, structural, electronic and optical studies of {4 - (2, 6) dichlorophenyl amino 2 - methylidene 4 - oxobutanoic acid and 4- (2, 5)} dichlorophenyl amino 2 - methylidene 4 - oxobutanoic acid - A comparative study

    NASA Astrophysics Data System (ADS)

    Vanasundari, K.; Balachandran, V.; Kavimani, M.; Narayana, B.

    2018-03-01

    Spectroscopic and structural investigations of 4 - [(2, 6 - dichlorophenyl) amino] 2 -methylidene 4 - oxobutanoic acid (6DAMB) and 4-[(2, 5- dichlorophenyl) amino] 2 - methylidene 4 - oxobutanoic acid (5DAMB) are presented by using experimental (FT-IR and FT-Raman) spectra and theoretical (DFT approach) calculations. Seventy-two characteristic vibrational bands of the title compounds were assigned and compared with available experimental data. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization was analyzed using natural bond orbital (NBO) analysis. Several descriptors determined from the energies of frontier molecular orbital (HOMO and LUMO) were applied to describe the reactivity of the title compound. The dipole moment and first hyperpolarizabilities of the studied compounds indicate that the compound is a good candidate of nonlinear optical materials. Theoretical Ultraviolet-Visible spectra of title compounds have been analyzed using the TD-DFT method. The noncovalent interactions like hydrogen bonding and Van der Waals interaction were identified from the molecular geometry and electron localization function. These interactions in molecules have been studied by using reduced density gradient (RDG) and graphed by Multiwfn. Auto-dock studies reveal that butanoic acid derivatives play a vital role in bonding and results draw us to the concluded that both compounds inhibit Placenta growth factor (PIGF-1) and that have good biological activities. This study may also provide further investigation on butanoic acid derivatives for pharmacological importance.

  4. Preparation of O/I1-type Emulsions and S/I1-type Dispersions Encapsulating UV-Absorbing Agents.

    PubMed

    Aramaki, Kenji; Kimura, Minami; Masuda, Kazuki

    2015-01-01

    Oil-in-cubic phase (O/I1) emulsions encapsulating the cosmetic UV absorbing agents 2-ethylhexyl 4-methoxycinnamate (EHMC), 2-ethylhexyl 2-cyano-3,3-diphenylacrylate (octocrylene, OCR) and 1-(4-tertbutylphenyl)-3-(4-methoxyphenyl)-1,3-propanedione (Avobenzone, TBMP) were prepared by vortex mixing accompanied by a heating-cooling process. A ternary phase diagram in a water/C12EO25/EHMC system at 25°C was constructed and the two-phase equilibrium of an oil phase and an I1 phase, which is necessary to prepare the O/I1-type emulsions, was confirmed. Also, the melting of the I1 phase into a fluid micellar solution phase was confirmed, allowing emulsification by a heating-cooling process. The O/I1-type emulsions were formulated in the ternary system as well as a quaternary system. The four-component system contained an additional cosolvent, isopropyl myristate (IPM). The use of the cosolvent allows the use of reduced amounts of EHMC, which is desirable because EHMC can cause temporary skin irritation. Formulation of the O/I1-type emulsions with other UV absorbing agents (OCR and TBMP) was also possible using the same emulsification method. When IPM was changed to tripalmitin, which has a melting point greater than room temperature, a solid-oil dispersion in I1 phase was formed. We have termed this a "solidin-cubic phase (S/I1) type dispersion". These novel emulsions have not been reported previously. The UV absorbability of the O/I1-type emulsions and S/I1-type dispersions that encapsulate the UV absorbing agents was confirmed by measurement of UV absorption spectra.

  5. Preparing Students for Future Learning with Teachable Agents

    ERIC Educational Resources Information Center

    Chin, Doris B.; Dohmen, Ilsa M.; Cheng, Britte H.; Oppezzo, Marily A.; Chase, Catherine C.; Schwartz, Daniel L.

    2010-01-01

    One valuable goal of instructional technologies in K-12 education is to prepare students for future learning. Two classroom studies examined whether Teachable Agents (TA) achieves this goal. TA is an instructional technology that draws on the social metaphor of teaching a computer agent to help students learn. Students teach their agent by…

  6. Efficacy of prokinetic agents in improving bowel preparation for colonoscopy.

    PubMed

    Mishima, Yuko; Amano, Yuji; Okita, Koichi; Takahashi, Yoshiko; Moriyama, Nobuyuki; Ishimura, Norihisa; Furuta, Kenji; Ishihara, Shunji; Adachi, Kyoichi; Kinoshita, Yoshikazu

    2008-01-01

    Colonoscopy plays an important role in the diagnosis and treatment of gastrointestinal illness in both Western countries and Japan. However, preparative bowel cleansing for colonoscopy is frequently troublesome for elderly and/or constipated patients, since they must drink larger volumes of lavage solution for adequate cleansing. We investigated the use of prokinetic agents for improving the efficacy and tolerability of bowel cleansing prior to colonoscopy. 613 patients were divided into two groups according to oral lavage solution used (polyethylene glycol or magnesium citrate), and were further randomized to receive either vehicle (100 ml water) alone, vehicle with 5 mg mosapride citrate, or vehicle with 50 mg itopride hydrochloride 30 min before administration of lavage solution. Experimental parameters included bowel cleansing quality, times to first defecation and completion of bowel cleansing, and incidence of uncomfortable abdominal symptoms during colonoscopy preparation. Administration of mosapride citrate or itopride hydrochloride prior to oral lavage solution did not significantly improve bowel cleansing quality. However, statistically significantly fewer uncomfortable abdominal symptoms were found in patients who received mosapride citrate or itopride hydrochloride versus vehicle alone. Prokinetic agents effectively decreased the incidence of uncomfortable abdominal symptoms experienced during colonoscopy preparation. Copyright 2008 S. Karger AG, Basel.

  7. A Theoretical Study on N'-[(Z)-(4-Methylphenyl)Methylidene]-4-Nitrobenzohydrazide (NMPMN)

    NASA Astrophysics Data System (ADS)

    Okur, Muhammet; Albayrak, Nazmiye; Tamer, Ömer; Avcı, Davut; Atalay, Yusuf

    2018-05-01

    Quantum mechanical calculations of ground state energy, vibration wavenumbers, and electronic absorption wavelengths of N'-[(Z)-(4-methylphenyl)methylidene]-4-nitrobenzohydrazide with C15H13N3O3 empirical formula was performed by using Gaussian 09 program. Becke's three-parameter exchange functional in conjunction with the Lee-Yang-Parr correlation functional and Heyd-Scuseria-Ernzerhof functional levels of density functional theory (DFT) with the 6-311++G(d,p) basis set were used in the performing of above mentioned calculations. The highest occupied and lowest unoccupied molecular orbital (HOMO and LUMO) energies have been also calculated at the same levels. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. Nonlinear optical (NLO) behavior of the title molecule has been examined by the determining of electric dipole moment (μ), polarizability (α), and static first-order hyperpolarizability (β). Finally, molecular electrostatic potential (MEP) surface as well as Mulliken and NBO atomic charges were calculated by using Gaussian 09 program.

  8. Thiazolo[3,2-b]-1,2,4-triazole-5(6H)-one substituted with ibuprofen: novel non-steroidal anti-inflammatory agents with favorable gastrointestinal tolerance.

    PubMed

    Uzgören-Baran, Ayşe; Tel, Banu Cahide; Sarıgöl, Deniz; Oztürk, Elif İnci; Kazkayası, Inci; Okay, Gürol; Ertan, Mevlüt; Tozkoparan, Birsen

    2012-11-01

    In an effort to establish new candidates with improved analgesic and anti-inflammatory activities and lower ulcerogenic risk, a series of thiazolo[3,2-b]-1,2,4-triazole-5(6H)-one derivatives of ibuprofen were synthesized. All compounds were evaluated for their in vivo anti-inflammatory and analgesic activities in mice. Furthermore, the ulcerogenic risks of the compounds were determined. In general, none of the compounds represent a risk for developing stomach injury as much as observed in the reference drugs ibuprofen and indomethacin. The compounds carrying a 3-phenyl-2-propenylidene (1a), (biphenyl-4-yl)methylidene (1f) and (1-methylpyrrol-2-yl)methylidene (1n) at the 6th position of the fused ring have been evaluated as potential analgesic/anti-inflammatory agents without a gastrointestinal side effect. These new compounds, therefore, deserve further attention to develop new lead drugs. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  9. Effect of blowing agents on the oxidation resistance of carbon foams prepared from molten sucrose

    NASA Astrophysics Data System (ADS)

    Narasimman, R.; Prabhakaran, K.

    2013-06-01

    We have prepared low density carbon foams from molten sucrose using aluminium nitrate and boric acid blowing agents. A comparative study of the oxidation resistance of the carbon foams prepared using the two blowing agents are reported in the present paper. Oxidation of the carbon foams was evaluated under isothermal and non-isothermal conditions in air atmosphere using thermogravimetric analysis (TGA). We have observed that the alumina produced from the aluminium nitrate blowing agent acts as a catalyst whereas the boron produced from boric acid inhibits the oxidation of the carbon foams. The oxidation resistance of carbon foams increases with boron concentration. The oxidation onset temperature for the carbon foams prepared using boric acid blowing agent was nearly 60°C higher than that prepared using aluminium nitrate blowing agent. Carbon foams prepared using aluminium nitrate blowing agent undergoes complete oxidation at temperature less than 700°C. Whereas that prepared using boric acid blowing agent leave ˜ 50 wt.% residue at 900°C. Further evidence is provided by the kinetic analysis of the TGA using Coats-Redfern (CR) equation.

  10. Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents

    DTIC Science & Technology

    2017-10-01

    factor in the development of skin graft contraction. Using a porcine model of skin graft contraction, we will screen for anti- inflammatory agents (dose...Award Number: W81XWH-14-2-0153 TITLE: Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents ...09/14/2017 4. TITLE AND SUBTITLE “Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents ” 5a

  11. Method for preparing radionuclide-labeled chelating agent-ligand complexes

    DOEpatents

    Meares, Claude F.; Li, Min; DeNardo, Sally J.

    1999-01-01

    Radionuclide-labeled chelating agent-ligand complexes that are useful in medical diagnosis or therapy are prepared by reacting a radionuclide, such as .sup.90 Y or .sup.111 In, with a polyfunctional chelating agent to form a radionuclide chelate that is electrically neutral; purifying the chelate by anion exchange chromatography; and reacting the purified chelate with a targeting molecule, such as a monoclonal antibody, to form the complex.

  12. Diastereoselective preparation of (R)- and (S)-2-methoxy-2-phenylpent-3-ynoic acids and their use as reliable chiral derivatizing agents.

    PubMed

    Pérez-Estrada, Salvador; Joseph-Nathan, Pedro; Jiménez-Vázquez, Hugo A; Medina-López, Manuel E; Ayala-Mata, Francisco; Zepeda, L Gerardo

    2012-02-17

    Benzoyl-S,O-acetals 1a and 1b were used as chiral auxiliaries to achieve the diastereoselective preparation of both enantiomers of 2-methoxy-2-phenylpent-3-ynoic acids (MPPAs). The latter were condensed with several chiral secondary alcohols and some primary amines to evaluate their potential as chiral derivatizing agents (CDAs). The (1)H NMR spectra of the corresponding esters and amides showed strong consistency with the absolute configuration of the carbinol and amine moieties, whose observed ΔδL(1) and ΔδL(2) values were in the ranges of 0.1-0.4 and 0.02-0.12 ppm, respectively.

  13. Nanodispersive mixed oxides for destruction of warfare agents prepared by homogeneous hydrolysis with urea

    NASA Astrophysics Data System (ADS)

    Daněk, Ondřej; Štengl, Václav; Bakardjieva, Snejana; Murafa, Nataliya; Kalendová, Andrea; Opluštil, Frantisek

    2007-05-01

    Nanocrystalline mixed oxides of Ti, Zn, Al and Fe were prepared by a homogeneous hydrolysis of sulphates with urea at temperature of 100 °C in an aqueous solution. The prepared samples were characterized by BET and BJH measurements, an X-ray powder diffraction and scanning electron microscopy. These oxides were taken for an experimental evaluation of their reactivity with yperite (2,2‧-dichloroethyl sulphide), soman (3,3-dimethyl-2-butyl methylphosphonofluoridate) and matter VX (O-ethyl S-2-(diisopropylamino)ethyl methylphosphonothionate). An excellent activity in decomposition of chemical warfare agents was observed in these materials (conversion degree higher then 96%/h).

  14. Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents

    DTIC Science & Technology

    2015-10-01

    AWARD NUMBER: W81XWH-14-2-0153 TITLE: Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti - Inflammatory Agents...Sep 2015 4. TITLE AND SUBTITLE Decreasing Skin Graft Contraction Through Topical Wound Bed Preparation with Anti - Inflammatory Agents 5a. CONTRACT...applied anti - inflammatory drugs that will reduce recipient site inflammation and skin graft contraction. 15. SUBJECT TERMS Graft contraction, anti

  15. Optical Properties of Synthesized Nanoparticles ZnS Using Methacrylic Acid as the Capping Agent

    NASA Astrophysics Data System (ADS)

    Nazerdeylami, Somayeh; Saievar Iranizad, Esmaiel; Molaei, Mehdi

    Optical analysis (UV-vis spectroscopy) of solution of ZnS nanoparticles prepared at room temperature by a chemical capping method using methacrylic acid (MAA) capping agent at concentration of 0.05, 0.2, 0.5 and 1.17 molar is investigated. The spectroscopy results indicate increasing of band gap of ZnS through increasing concentration of the methacrylic acid as capping agent in the solution. According to the relation of Effective Mass Approximation, it is concluded that the size of nanoparticles decreased with the increasing concentration of the capping agent in the tested solutions. The size of the particles is found to be in 1.77-2.05 nm range.

  16. A New Approach in the Preparation of Dendrimer-Based Bifunctional Diethylenetriaminepentaacetic Acid MR Contrast Agent Derivatives

    PubMed Central

    Nwe, Kido; Xu, Heng; Regino, Celeste Aida S.; Bernardo, Marcelino; Ileva, Lilia; Riffle, Lisa; Wong, Karen J.; Brechbiel, Martin W.

    2009-01-01

    In this paper we report a new method to prepare and characterize a contrast agent based on a fourth-generation (G4) polyamidoamine (PAMAM) dendrimer conjugated to the gadolinium complex of the bifunctional diethylenetriamine pentaacetic acid derivative (1B4M-DTPA). The method involves pre-forming the metal-ligand chelate in alcohol prior to conjugation to the dendrimer. The dendrimer-based agent was purified by a Sephadex® G-25 column and characterized by elemental analysis. The analysis and SEHPLC data gave a chelate to dendrimer ratio of 30:1 suggesting conjugation at approximately every other amine terminal on the dendrimer. Molar relaxivity of the agent measured at pH 7.4 displayed a higher value than that of the analogous G4 dendrimer based agent prepared by the post-metal incorporation method (r1 = 26.9 vs. 13.9 mM-1s-1 at 3T and 22°C). This is hypothesized to be due to the higher hydrophobicity of this conjugate, and the lack of available charged carboxylate groups from non-complexed free ligands that might coordinate to the metal and thus also reduce water exchange sites. Additionally, the distribution populations of compounds that result from the post-metal incorporation route are eliminated from the current product simplifying characterization as quality control issues pertaining to the production of such agents for clinical use as MR contrast agents. In vivo imaging in mice showed a reasonably fast clearance (t1/2 = 24 min) suggesting a viable agent for use in clinical application. PMID:19555072

  17. A new approach in the preparation of dendrimer-based bifunctional diethylenetriaminepentaacetic acid MR contrast agent derivatives.

    PubMed

    Nwe, Kido; Xu, Heng; Regino, Celeste Aida S; Bernardo, Marcelino; Ileva, Lilia; Riffle, Lisa; Wong, Karen J; Brechbiel, Martin W

    2009-07-01

    In this paper, we report a new method to prepare and characterize a contrast agent based on a fourth-generation (G4) polyamidoamine (PAMAM) dendrimer conjugated to the gadolinium complex of the bifunctional diethylenetriamine pentaacetic acid derivative (1B4M-DTPA). The method involves preforming the metal-ligand chelate in alcohol prior to conjugation to the dendrimer. The dendrimer-based agent was purified by a Sephadex G-25 column and characterized by elemental analysis. The analysis and SE-HPLC data gave a chelate to dendrimer ratio of 30:1 suggesting conjugation at approximately every other amine terminal on the dendrimer. Molar relaxivity of the agent measured at pH 7.4 displayed a higher value than that of the analogous G4 dendrimer based agent prepared by the postmetal incorporation method (r(1) = 26.9 vs 13.9 mM(-1) s(-1) at 3 T and 22 degrees C). This is hypothesized to be due to the higher hydrophobicity of this conjugate and the lack of available charged carboxylate groups from noncomplexed free ligands that might coordinate to the metal and thus also reduce water exchange sites. Additionally, the distribution populations of compounds that result from the postmetal incorporation route are eliminated from the current product simplifying characterization as quality control issues pertaining to the production of such agents for clinical use as MR contrast agents. In vivo imaging in mice showed a reasonably fast clearance (t(1/2) = 24 min) suggesting a viable agent for use in clinical application.

  18. Preparation and characterization of silver chloride nanoparticles as an antibacterial agent

    NASA Astrophysics Data System (ADS)

    Duong Trinh, Ngoc; Thanh Binh Nguyen, Thi; Hai Nguyen, Thanh

    2015-12-01

    Silver chloride nanoparticles were prepared by the precipitation reaction between silver nitrate and sodium chloride in an aqueous solution containing poly(vinyl alcohol) as a stabilizing agent. Different characteristics of the nanoparticles in suspension and in lyophilized powder such as size, morphology, chemical nature, interaction with stabilizing agent and photo-stability were investigated. Biological tests showed that the obtained silver chloride nanoparticles displayed antibacterial activities against Escherichia coli and Staphylococcus aureus.

  19. Preparing Change Agents for Change Agent Roles.

    ERIC Educational Resources Information Center

    Sedlacek, James R.

    Seventy-seven Spanish- and Portuguese-speaking agricultural change agents from developing Central and South American countries responded to a questionnaire which sought perceptions of the roles in which the change agents felt they were involved and the roles for which they felt they were being trained. The agents were participating in training…

  20. Preparation of Shrinkage Compensating Concrete with HCSA Expansive Agent

    NASA Astrophysics Data System (ADS)

    Li, Changcheng; Jia, Fujia

    2017-10-01

    Shrinkage compensating concrete (SCC) has become one of the best effective methods of preventing and reducing concrete cracking. SCC is prepared by HCSA high performance expansive agent for concrete which restrained expansion rate is optimized by 0.057%. Slump, compressive strength, restrained expansion rate and cracking resistance test were carried out on SCC. The results show that the initial slump of fresh SCC was about 220mm-230mm, while slump after 2 hours was 180mm-200mm. The restrained expansion rate of SCC increased with the mixing amount of expansive agent. After cured in water for 14 days, the restrained expansion rate of C35 and C40 SCC were 0.020%-0.032%. With the dosage of expansive agent increasing, restrained expansion rate of SCC increased, maximum compressive stress and cracking stress improved, cracking temperature fell, thus cracking resistance got effectively improvement.

  1. Preparation of In2S3 nanopraricle by ultrasonic dispersion and its tribology property.

    PubMed

    Li, Zhiwei; Tao, Xiaojun; Wu, Zhishen; Zhang, Pingyu; Zhang, Zhijun

    2009-02-01

    In this paper, we describe a facile and rapid method for preparing In2S3 nanoparticles via ultrasound dispersion. This method allows us to prepare In2S3 nanoparticles from bulk indium and sulfur with ease and without using expensive agents and in a short time. The possible growing mechanism of the In2S3 nanoparticles was presented. In addition, we provide detailed characterizations including TEM, XRD, TG-DTA, and XPS to study the shape, composition and structure of In2S3 nanoparticles. We also studied the tribology property of In2S3 nanoparticles made using this novel recipe.

  2. Preparing School Leaders to Serve as Agents for Social Transformation

    ERIC Educational Resources Information Center

    Brown, Kathleen M.

    2010-01-01

    The major priorities that should guide leadership education in preparing leaders for their work of leading schools in a democratic society are: (1) Teaching leaders to understand the inequities of society; (2) Teaching leaders to serve as agents for social transformation; and (3) Teaching leaders to help each and every student learn and succeed.…

  3. Divergent Pathways Involving 1,3-Dipolar Addition and N-N Bond Splitting of an Organic Azide across a Zirconium Methylidene.

    PubMed

    Kurogi, Takashi; Mane, Manoj V; Zheng, Shuai; Carroll, Patrick J; Baik, Mu-Hyun; Mindiola, Daniel J

    2018-02-12

    The zirconium methylidene (PNP)Zr=CH 2 (OAr) (1) reacts with N 3 Ad to give two products (PNP)Zr=NAd(OAr) (2) and (PNP)Zr(η 2 -N=NAd)(N=CH 2 )(OAr) (3), both resulting from a common cycloaddition intermediate (PNP)Zr(CH 2 N 3 Ad)(OAr) (A). Using a series of control experiments in combination with DFT calculations, it was found that 2 results from a nitrene by a carbene metathesis reaction in which N 2 acts as a delivery vehicle and forms N 2 CH 2 as a side product. In the case of 3, N-N bond splitting of the azide at the α-position allowed the isolation of a rare example of a parent ketimide complex of zirconium. Isotopic labeling studies and solid-state X-ray analysis are presented for 2 and 3, in addition to an independent synthesis for the former. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Preparation of near-infrared-labeled targeted contrast agents for clinical translation

    NASA Astrophysics Data System (ADS)

    Olive, D. Michael

    2011-03-01

    Targeted fluorophore-labeled contrast agents are moving toward translation to human surgical use. To prepare for future clinical use, we examined the performance of potential ligands targeting the epidermal growth factor receptor, α5β3 integrins, and GLUT transporters for their suitability as directed contrast agents. Each agent was labeled with IRDye 800CW, and near-infrared dye with excitation/emission wavelengths of 789/805 nm, which we determined had favorable toxicity characteristics. The probe molecules examined consisted of Affibodies, nanobodies, peptides, and the sugar 2-deoxy-D-glucose. Each probe was tested for specific and non-specific binding in cell based assays. All probe types showed good performance in mouse models for detecting either spontaneous tumors or tumor xenografts in vivo. Each of the probes tested show promise for future human clinical studies.

  5. Hierarchical porous carbon materials prepared using nano-ZnO as a template and activation agent for ultrahigh power supercapacitors.

    PubMed

    Wang, Haoran; Yu, Shukai; Xu, Bin

    2016-09-20

    Hierarchical porous carbon materials with high surface areas and a localized graphitic structure were simply prepared from sucrose using nano-ZnO as a hard template, activation agent and graphitization catalyst simultaneously, which exhibit an outstanding high-rate performance and can endure an ultrafast scan rate of 20 V s -1 and ultrahigh current density of 1000 A g -1 .

  6. Investigation of Air-Liquid Interface Rings in Buffer Preparation Vessels: the Role of Slip Agents.

    PubMed

    Shi, Ting; Ding, Wei; Kessler, Donald W; De Mas, Nuria; Weaver, Douglas G; Pathirana, Charles; Martin, Russell D; Mackin, Nancy A; Casati, Michael; Miller, Scott A; Pla, Itzcoatl A

    2016-01-01

    Air-liquid interface rings were observed on the side walls of stainless steel buffer vessels after certain downstream buffer preparations. Those rings were resistant to regular cleaning-in-place procedures but could be removed by manual means. To investigate the root cause of this issue, multiple analytical techniques, including liquid chromatography with tandem mass spectrometry detection (LC-MS/MS), high-resolution accurate mass liquid chromatography with mass spectrometry, nuclear magnetic resonance, Fourier transform infrared spectroscopy, and scanning electron microscopy with energy-dispersive X-ray spectroscopy have been employed to characterize the chemical composition of air-liquid interface rings. The main component of air-liquid interface rings was determined to be slip agents, and the origin of the slip agents can be traced back to their presence on raw material packaging liners. Slip agents are commonly used in plastic industry as additives to reduce the coefficient of friction during the manufacturing process of thin films. To mitigate this air-liquid interface ring issue, an alternate liner with low slip agent was identified and implemented with minimal additional cost. We have also proactively tested the packaging liners of other raw materials currently used in our downstream buffer preparation to ensure slip agent levels are appropriate. Air-liquid interface rings were observed on the side walls of stainless steel buffer vessels after certain downstream buffer preparations. To investigate the root cause of this issue, multiple analytical techniques have been employed to characterize the chemical composition of air-liquid interface rings. The main components of air-liquid interface rings were determined to be slip agents, which are common additives used in the manufacturing process of thin films. The origin of the slip agents can be traced back to their presence on certain raw material packaging liners. To mitigate this air-liquid interface ring

  7. Preparation and mechanism analysis of an environment-friendly maize seed coating agent.

    PubMed

    Zeng, Defang; Fan, Zhao; Tian, Xu; Wang, Wenjin; Zhou, Mingchun; Li, Haochuan

    2018-06-01

    Traditional seed coating agents often contain toxic ingredients, which contaminate the environment and threaten human health. This paper expounds a method of preparing a novel environment-friendly seed coating agent for maize and researches its mechanism of action. The natural polysaccharide polymer, which is the main active ingredient of this environment-friendly seed coating agent, has the characteristics of innocuity and harmlessness, and it can replace the toxic ingredients used in traditional seed coating agents. This environment-friendly seed coating agent for maize was mainly made up of the natural polysaccharide polymer and other additives. The field trials results showed that the control efficacy of Helminthosporium maydis came to 93.72%, the anti-feeding rate of cutworms came to 81.29%, and the maize yield was increased by 17.75%. Besides, the LD 50 value (half the lethal dose in rats) of this seed coating agent was 10 times higher than that of the traditional seed coating agents. This seed coating agent could improve the activity of plant protective enzymes (peroxidase, catalase and superoxidase dismutase) and increase the chlorophyll content. This seed coating agent has four characteristics of disease prevention, desinsectization, increasing yield and safety. Results of mechanism analyses showed that this seed coating agent could enhance disease control effectiveness by improving plant protective enzymes activity and increase maize yield by improving chlorophyll content. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  8. Preparation of amine-impregnated silica foams using agar as the gelling agent

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jardim, Iara M., E-mail: iaramj01@yahoo.com.br

    In this work we successfully prepared amine-impregnated gel-cast silica foams using agar and atmospheric air as the gelling agent and heat treatment atmosphere, respectively. The concentration of 3,6-anhydrogalactose in agar was evaluated by ultraviolet–visible spectroscopy (UV–Vis). The obtained foams were examined by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG) coupled to mass spectrometry (TG-MS), scanning electron microscopy (SEM), X-ray microtomography (micro-CT), and Archimedes method. The cold crushing strength of the materials prepared in this work was assessed using a mechanical testing stage available in the micro-CT system. The obtained foams exhibited a highly interconnected pore network, with an expressivemore » presence of open pores. Samples heat-treated at 1300 °C for 2 h showed both an expressive porosity (≈ 77%) and a significant cold crushing strength (≈ 1.4 MPa). It was observed that the calcination of the prepared materials at 1200 °C for times as long as 16 h may lead to the rupture of pore walls. FTIR and TG-MS revealed that amine groups were properly incorporated into the foams structure. - Highlights: •Successful preparation of amine-impregnated gel-cast silica foams •Agar used as the gelling agent •Samples with expressive porosity and cold crushing strength •Sintering times as long as 16 h led to the rupture of the pore network.« less

  9. A two-dimensional ZnII coordination polymer constructed from benzene-1,2,3-tricarboxylic acid and N,N'-bis[(pyridin-4-yl)methylidene]hydrazine.

    PubMed

    Wang, Xiangfei; Yang, Fang; Tang, Meng; Yuan, Limin; Liu, Wenlong

    2015-07-01

    The hydrothermal synthesis of the novel complex poly[aqua(μ4-benzene-1,2,3-tricarboxylato)[μ2-4,4'-(hydrazine-1,2-diylidenedimethanylylidene)dipyridine](μ3-hydroxido)dizinc(II)], [Zn(C9H3O6)(OH)(C12H10N4)(H2O)]n, is described. The benzene-1,2,3-tricarboxylate ligand connects neighbouring Zn4(OH)2 secondary building units (SBUs) producing an infinite one-dimensional chain. Adjacent one-dimensional chains are connected by the N,N'-bis[(pyridin-4-yl)methylidene]hydrazine ligand, forming a two-dimensional layered structure. Adjacent layers are stacked to generate a three-dimensional supramolecular architecture via O-H...O hydrogen-bond interactions. The thermal stability of this complex is described and the complex also appears to have potential for application as a luminescent material.

  10. Foaming Betadine Spray as a potential agent for non-labor-intensive preoperative surgical site preparation.

    PubMed

    Kargupta, Roli; Hull, Garret J; Rood, Kyle D; Galloway, James; Matthews, Clinton F; Dale, Paul S; Sengupta, Shramik

    2015-04-02

    The Centers for Disease Control and Prevention's (CDC) National Healthcare Safety Network (NHSN) report published in 2009 shows that there were about 16,000 cases of surgical site infection (SSI) following ~ 850,000 operative procedures making SSI one of the most predominant infection amongst nosocomial infections. Preoperative skin preparation is a standard procedure utilized to prevent SSIs thereby improving patient outcomes and controlling associated healthcare costs. Multiple techniques/ products have been used for pre-operative skin preparation, like 2 step scrubbing and painting, 2 step scrubbing and drying, and 1 step painting with a drying time. However, currently used products require strict, time consuming and labor-intensive protocols that involve repeated mechanical scrubbing. It can be speculated that a product requiring a more facile protocol will increase compliance, thus promoting a reduction in SSIs. Hence, the antimicrobial efficacy of a spray-on foaming formulation containing Betadine (povidone-iodine aerosol foam) that can be administered with minimum effort is compared to that of an existing formulation/technique (Wet Skin Scrub). In vitro antimicrobial activities of (a) 5% Betadine delivered in aerosolized foam, (b) Wet Skin Scrub Prep Tray and (c) liquid Betadine are tested against three clinically representative microorganisms (S. aureus, S. epidermidis and P. aeruginosa,) on two surfaces (agar-gel on petri-dish and porcine skin). The log reduction/growth of the bacteria in each case is noted and ANOVA statistical analysis is used to establish the effectiveness of the antimicrobial agents, and compare their relative efficacies. With agar gel as the substrate, no growth of bacteria is observed for all the three formulations. With porcine skin as the substrate, the spray-on foam's performance was not statistically different from that of the Wet Skin Scrub Prep technique for the microorganisms tested. The povidone-iodine aerosolized foam

  11. A novel bubble-forming material for preparing hydrophobic-agent-loaded bubbles with theranostic functionality.

    PubMed

    Yang, Pei-Sin; Tung, Fu-I; Chen, Hsiao-Ping; Liu, Tse-Ying; Lin, Yi-Ying

    2014-08-01

    In the present study, a new bubble-forming material (carboxymethyl hexanoyl chitosan, CHC), together with superparamagnetic iron oxide (SPIO) nanoparticles, was employed to prepare image-guided bubbles for efficiently encapsulating and delivering hydrophobic agents to kill tumor cells. The results showed that CHC could be used for preparing not only micronized bubbles (CHC/SPIO MBs) to exhibit ultrasound imaging functionality but also nanosized bubbles (CHC/SPIO NBs) to exhibit magnetic resonance T2 image contrast. It was found that the amounts of SPIO nanoparticles and hexane during preparation process were the key factors to obtaining CHC/SPIO NBs. Most importantly, under in vitro cell culture conditions with the same amount of camptothecin (CPT) and therapeutic sonication, CPT-loaded CHC/SPIO NBs demonstrated more significant transcellular delivery and cytotoxicity than free CPT. Subsequently, an intratumoral injection was proposed for the in vivo administration of hydrophobic-agent-loaded CHC/SPIO NBs. After injection, the distribution of a hydrophobic dye (DiR, an agent with near-infrared (NIR) fluorescence used as a model drug) released from the CHC/SPIO NBs was tracked by an NIR imaging technique. A significant tumor-specific accumulation was observed in the mouse that received the DiR-loaded CHC/SPIO NBs; the same was not observed in the mouse that received the free dye (without incorporating with CHC/SPIO NBs). It is expected, in the future, both the dose of the therapeutic agent administered and its side effects can be significantly lowered by using novel CHC/SPIO NBs together with local delivery (intratumoral injection), targeted imaging and enhanced cellular uptake of the drug. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Preparing Medical Students as Agentic Learners through Enhancing Student Engagement in Clinical Education

    ERIC Educational Resources Information Center

    Richards, Janet; Sweet, Linda; Billett, Stephen

    2013-01-01

    Preparing medical students to be agentic learners is held to be increasingly important. This is because beyond sequencing, enhancing and varying of experiences across university and health care settings, medical students require epistemological agency to optimize their learning. The positioning of students in these settings, and their engagement…

  13. Studies on the inhibition of tumor cell growth and microtubule assembly by 3-hydroxy-4-[(E)-(2-furyl)methylidene]methyl-3-cyclopentene-1,2-dione, an intensively coloured Maillard reaction product.

    PubMed

    Marko, D; Kemény, M; Bernady, E; Habermeyer, M; Weyand, U; Meiers, S; Frank, O; Hofmann, T

    2002-01-01

    Very recently, 3-hydroxy-4-[(E)-(2-furyl)methylidene]methyl-3-cyclopentene-1,2-dione (1) has been successfully identified as an intensively coloured Maillard product formed from glucose and L-proline upon thermal food processing. Using a biomimetic synthetic strategy, reference material of compound 1 was prepared and purified, and then used to study its effect on the growth of human tumor cells. Compound 1 was found to potently inhibit the growth of human tumor cells in vitro. Using a reporter gene assay we could show that in growth inhibitory concentrations compound 1 effectively inhibits the phosphorylation of the transcription factor Elk-1. In addition, 1 was found to affect the microtubule skeleton. The human mammary carcinoma cell line MCF-7 exhibits a decrease of the microtubule organisation when treated for 24 h with 1 (> or =20 microM). At concentrations of 30 microM and above a loss of microtubule integrity is observed after 1 h incubation. In vitro studies demonstrated that the polymerisation and, to a minor extent, also the depolymerisation of tubulin, isolated and purified from bovine brain, is inhibited in a dose-dependent manner at concentrations of 30 microM and above. This is the first time that a non-enzymatically formed browning compound of known structure was reported to effectively inhibit tumor cell growth and microtubule assembly.

  14. Entrepreneurial Attitudes and Behaviors that Can Help Prepare Successful Change-Agents in Education

    ERIC Educational Resources Information Center

    Borasi, Raffaella; Finnigan, Kara

    2010-01-01

    This article explores how the preparation of educators committed to improving education can capitalize on entrepreneurship when broadly defined as "transforming ideas into enterprises that generate economic, intellectual and/or social value." The article reports on the case-studies of six educators who have been successful change-agents in a…

  15. Preparation and thermal properties of Glauber’s salt-based phase-change materials for Qinghai-Tibet Plateau solar greenhouses

    NASA Astrophysics Data System (ADS)

    Jiang, Zipeng; Tie, Shengnian

    2017-07-01

    This paper reports the preparation and characterization of eutectic Glauber’s salt-based composite, phase-change materials (G-PCMs). PCMs were prepared using industrial-grade sodium sulfate decahydrate (Na2SO4 ṡ 10H2O) as the basic material. Other salts were added to obtain the eutectic Glauber’s salt-based PCMs with phase-change temperatures of 25∘C, 15∘C and 10∘C. The modification of the G-PCMs was designed using the same experimental method to select the efficient nucleating, thickening and thermal conductive agents. The results show that borax can be an effective nucleating agent, sodium carboxymethyl cellulose is an excellent thickener and carbon powder is a good thermal conductive agent. The phase-change temperature, latent heat and thermal conductivity of the three different PCMs are 23.9∘C, 15.4∘C and 9.5∘C; 179.6, 129 and 116.2 J/g; and 1.02, 1.10 and 1.23 W/(m K), respectively. These PCMs possess suitable phase-change temperature, high latent heat and good thermal conductivity, and can be used in Qinghai-Tibet Plateau agricultural solar greenhouses.

  16. Preparation of thermo-responsive graft copolymer by using a novel macro-RAFT agent and its application for drug delivery.

    PubMed

    Song, Cunfeng; Yu, Shirong; Liu, Cheng; Deng, Yuanming; Xu, Yiting; Chen, Xiaoling; Dai, Lizong

    2016-05-01

    A methodology to prepare thermo-responsive graft copolymer by using a novel macro-RAFT agent was proposed. The macro-RAFT agent with pendant dithioester (ZC(S)SR) was facilely prepared via the combination of RAFT polymerization and esterification reaction. By means of ZC(S)SR-initiated RAFT polymerization, the thermo-responsive graft copolymer consisting of poly(methyl methacrylate-co-hydroxylethyl methacrylate) (P(MMA-co-HEMA)) backbone and hydrophilic poly(N-isopropylacrylamide) (PNIPAAm) side chains was constructed through the "grafting from" approach. The chemical compositions and molecular weight distributions of the synthesized polymers were respectively characterized by (1)H nuclear magnetic resonance ((1)H NMR) and gel permeation chromatography (GPC). Self-assembly behavior of the amphiphilic graft copolymers (P(MMA-co-HEMA)-g-PNIPAAm) was studied by transmission electron microscopy (TEM), dynamic light scattering (DLS) and spectrofluorimeter. The critical micelle concentration (CMC) value was 0.052 mg mL(-1). These micelles have thermo-responsibility and a low critical solution temperature (LCST) of 33.5°C. Further investigation indicated that the guest molecule release property of these micelles, which can be well described by a first-order kinetic model, was significantly affected by temperature. Besides, the micelles exhibited excellent biocompatibility and cellular uptake property. Hence, these micelles are considered to have potential application in controlled drug delivery. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. An evaluation of smear layer with various desensitizing agents after tooth preparation.

    PubMed

    Zaimoglu, A; Aydin, A K

    1992-09-01

    According to hydrodynamics, any agent blocking the dentinal tubules reduces the flow of fluids and diminishes hypersensitivity. The properties of the desensitizing agents that sponsor tubular occlusion and the barrier efficiency resulting from the interaction of the smear layer with test materials were examined with the scanning electron microscope and energy-dispersive x-ray microanalysis. Selected dentinal desensitizing was accomplished with burnishing procedures, cavity varnish, calcium hydroxide, and topical fluoride. Subjective evaluations were also recorded clinically after tooth preparation. This investigation indicated that the smear layer did not protect against zinc phosphate cement, and that cavity varnish prevented the formation of the smear plugs. The smear layer and plugs were basically composed of calcium and phosphorus, the major ingredients of dentin.

  18. Spectroscopic (FT-IR and UV-Vis) and theoretical (HF and DFT) investigation of 2-Ethyl-N-[(5-nitrothiophene-2-yl)methylidene]aniline

    NASA Astrophysics Data System (ADS)

    Ceylan, Ümit; Tarı, Gonca Özdemir; Gökce, Halil; Ağar, Erbil

    2016-04-01

    Crystal structure of the title compound, 2-Ethyl-N-[(5-nitrothiophene-2-yl)methylidene]aniline, C13H12N2O2S, has been synthesized and characterized by FT-IR and UV-Vis spectrum. The compound crystallized in the monoclinic space group P 21/c with a = 11.3578 (4) Å, b = 7.4923 (2) Å, c = 14.9676 (6) Å and β = 99.589 (3)° and Z = 4 in the unit cell. The molecular geometry was also calculated using the Gaussian 03 software and structure was optimized using the HF and DFT/B3LYP methods with the 6-311++G(d,p) basis set in ground state. Using the TD-DFT method, the electronic absorption spectra of the title compound was computed in both the gas phase and ethanol solvent. The harmonic vibrational frequencies of the title compound were calculated using the same methods with the 6-311++G(d,p) basis set. The calculated results were compared with the experimental determination results of the compound. It was seen that the optimized structure was in excellent agreement with the X-ray crystal structure. The energetic behaviors of the title compound in solvent media were examined using the HF and DFT/B3LYP methods with the 6-311++G(d,p) basis set applying the polarizable continuum model (PCM). In addition, the molecular orbitals (FMOs) analysis, molecular electrostatic potential (MEP), nonlinear optical and thermodynamic properties of the title compound were performed using the same methods with the 6-311++G(d,p) basis set.

  19. [Preparation and preliminary evaluation of KGDS-targeted ultrasound contrast agent].

    PubMed

    Gao, Feng; Ding, Yanfei; Sheng, Xiaoxi; Wang, Wei; Liang, Qi; Luo, Zhuoqiong; Zhou, Ping; Li, Hui

    2009-12-01

    To prepare a thrombus-targeted ultrasonic contrast agent and to investigate its targeted ability to fresh blood clots. We first synthesized FITC-KGDS-Palm compound, and then prepared thrombus-targeted microbubbles using "ultrasound & high speed shearing method". Fluorescence labeling thrombus-specific peptides and KGDS, directed at the activated glycoprotein(GP)IIb/IIIa receptor of platelets were attached to the surface of lipid microbubbles. The concentration and size of TUCA were measured by Malvern Zeta Sizer Nano-ZS590 and Coulter counter. Immunofluorescence was applied to confirm the conjugation. The conjunct ratio was assessed by flow cytometer (FCM). The KGDS-TUCA was straw yellow turbid liquor, and the concentration was 1.5 x 10(9)/mL, and the average size was 1.5 microm. The targeted microbubbles conjugated with the thrombus-specific peptides showed bright green rings by fluorescence microscope. FCM demonstrated that the wavelength of shell of KGDS-TUCA changed greatly, and the conjunct ratio was 90.04%. In vitro study showed KGDS-TUCA remained stable for 48 h at 4 degree C and target-attached to blood clots and showed good stability. The ultrasound & high speed shearing method to prepare TUCA is easy and in favor of purification. KGDS-TUCA has high specific biological activity. The conjunct ratio and stability of KGDS-TUCA are excellent.

  20. A case study of preservation of semi-solid preparations using the European Pharmacopoeia test: comparative efficacy of antimicrobial agents in zinc gelatin.

    PubMed

    Favet, J; Chappuis, M L; Doelker, E

    2001-09-01

    The present study was undertaken with the aim of finding an alternative preservative system to methyl parahydroxybenzoate in zinc gelatin, which was described in the monographs of the Swiss Pharmacopoeia (until Ph. Helv. 8) and in previous editions of the German Pharmacopoeia (until DAB 7). This antimicrobial agent has now been withdrawn in the DAB, because of its potential allergy risks. As for the USP and DAB-DDR zinc gelatin preparations, they have always been devoid of any preservative agent, probably relying on the mild antimicrobial activity of zinc. A literature survey did not reveal if such an aqueous preparation containing the water-insoluble zinc oxide shows efficacious antimicrobial activity by itself. Thus, a comparative evaluation of differently preserved zinc gelatin preparations was performed using a test for the efficacy of antimicrobial preservation that has been modified with regard to the European Pharmacopoeia (EP) test to take into account the solid state of the preparations and the bactericidal effect of the zinc. Three zinc gelatin preparations were checked, either: (i), without any agent; or (ii), with 0.1% methyl parahydroxybenzoate; or (iii), with 0.5% phenoxyethanol, a broad-spectrum antimicrobial agent almost devoid of allergy risks. The three preparations behave quite differently, in particular with respect to fungi. All three preparations passed the modified EP test as far as bacteria are concerned. Even zinc gelatin without preservative is very effective, not only because of the mild antimicrobial activity of zinc (the soluble fraction of zinc oxide in the liquid phase of zinc gelatin was determined to be 13 microg/ml), but most probably because of the low water activity of the preparation (measured as around 0.81), as shown by the absence of growth of a zinc-resistant strain of Pseudomonas aeruginosa. Zinc gelatin preserved with methyl parahydroxybenzoate has a weak, although satisfactory, activity against Staphylococcus aureus

  1. Structure and spectroscopic investigations of a bi-dentate N‧-[(4-ethylphenyl)methylidene]-4-hydroxybenzohydrazide and its Co(II), Ni(II), Cu(II) and Cd(II) complexes: Insights relevant to biological properties

    NASA Astrophysics Data System (ADS)

    Gopal Reddy, N. B.; Krishna, P. Murali; Shantha Kumar, S. S.; Patil, Yogesh P.; Nethaji, Munirathinam

    2017-06-01

    The present paper describes the synthesis of novel ligand, N‧-[(4-ethylphenyl)methylidene]-4-hydroxy benzohydrazide (HL) and its Co(II), Ni(II), Cu(II) and Cd(II) complexes. The ligand (HL) crystallizes in orthorhombic lattice in P212121 space group with a = 7.9941 (7) Å, b = 11.6154 (10) Å, c = 15.2278 (13) Å, α = β = γ = 90°. Spectroscopic data gives the strong evidence that ligand is coordinated through azomethine nitrogen and enolic oxygen with metal ion. The DNA binding studies revealed that the complexes bind to CT-DNA via intercalation/electrostatic interaction. All the targeted compounds showed more pronounced DNA cleavage activity in the presence of H2O2 and also inhibit the growth of in vitro antibacterial activity against Gram-positive and Gram-negative bacteria.

  2. Synthesis, spectroscopic, structural and optical studies of Ru2S3 nanoparticles prepared from single-source molecular precursors

    NASA Astrophysics Data System (ADS)

    Mbese, Johannes Z.; Ajibade, Peter A.

    2017-09-01

    Homonuclear tris-dithiocarbamato ruthenium(III) complexes, [Ru(S2CNR2)3] were prepared and characterized by spectroscopic techniques and thermogravimetric analyses. The thermogravimetric analyses (TGA) of the ruthenium complexes showed that the complexes decompose to ruthenium(III) sulfide nanoparticles. The ruthenium(III) complexes were dispersed in oleic acid and thermolysed in hexadecylamine to prepared oleic acid/hexadecylamine capped Ru2S3 nanoparticles. FTIR revealed that Ru2S3 nanoparticles are capped through the interaction of the -NH2 group of hexadecylamine HDA adsorbed on the surfaces of nanoparticles and it also showed that oleic acid (OA) is acting as both coordinating stabilizing surfactant and capping agent. EDS spectra revealed that the prepared nanoparticles are mainly composed of Ru and S, confirming the formation of Ru2S3 nanoparticles. Powder XRD confirms that the nanoparticles are in cubic phase. The inner morphology of nanoparticles obtained from transmission electron microscopy (TEM) showed nanoparticles with narrow particle size distributions characterized by an average diameter of 8.45 nm with a standard deviation of 1.6 nm. The optical band gap (Eg) determined from Tauc plot are in the range 3.44-4.18 eV.

  3. Metal-isonitrile adducts for preparing radionuclide complexes for labelling and imaging agents

    DOEpatents

    Jones, Alun G.; Davison, Alan; Abrams, Michael J.

    1987-01-01

    A method for preparing a coordination complex of an isonitrile ligand and radionuclide such as Tc, Ru, Co, Pt, Fe, Os, Ir, W, Re, Cr, Mo, Mn, Ni, Rh, Pd, Nb and Ta is disclosed. The method comprises preparing a soluble metal adduct of said isonitrile ligand by admixing said ligand with a salt of a displaceable metal having a complete d-electron shell selected from the group consisting of Zn, Ga, Cd, In, Sn, Hg, Tl, Pb and Bi to form a soluble metal-isonitrile salt, and admixing said metal isonitrile salt with a salt comprising said radioactive metal in a suitable solvent to displace said displaceable metal with the radioactive metal thereby forming said coordination. The complex is useful as a diagnostic agent for labelling liposomes or vesicles, and selected living cells containing lipid membranes, such as blood clots, myocardial tissue, gall bladder tissue, etc.

  4. The Promise of Neuroprotective Agents in Parkinson’s Disease

    PubMed Central

    Seidl, Stacey E.; Potashkin, Judith A.

    2011-01-01

    Parkinson’s disease (PD) is characterized by loss of dopamine neurons in the substantia nigra of the brain. Since there are limited treatment options for PD, neuroprotective agents are currently being tested as a means to slow disease progression. Agents targeting oxidative stress, mitochondrial dysfunction, and inflammation are prime candidates for neuroprotection. This review identifies Rasagiline, Minocycline, and creatine, as the most promising neuroprotective agents for PD, and they are all currently in phase III trials. Other agents possessing protective characteristics in delaying PD include stimulants, vitamins, supplements, and other drugs. Additionally, combination therapies also show benefits in slowing PD progression. The identification of neuroprotective agents for PD provides us with therapeutic opportunities for modifying the course of disease progression and, perhaps, reducing the risk of onset when preclinical biomarkers become available. PMID:22125548

  5. Regeneration of Three-Way Automobile Catalysts using Biodegradable Metal Chelating AgentS, S-Ethylenediamine Disuccinic Acid (S, S-EDDS)

    EPA Science Inventory

    Regeneration of the activity of three-way catalytic converters (TWCs) was tested for the first time using a biodegradable metal chelating agent (S, S. Ethylenediamine disuccinic acid (S, S-EDDS). The efficiency of this novel environmentally friendly solvent in removing various c...

  6. Therapeutic strategies with oral fluoropyrimidine anticancer agent, S-1 against oral cancer.

    PubMed

    Harada, Koji; Ferdous, Tarannum; Ueyama, Yoshiya

    2017-08-01

    Oral cancer has been recognized as a tumor with low sensitivity to anticancer agents. However, introduction of S-1, an oral cancer agent is improving treatment outcome for patients with oral cancer. In addition, S-1, as a main drug for oral cancer treatment in Japan can be easily available for outpatients. In fact, S-1 exerts high therapeutic effects with acceptable side effects. Moreover, combined chemotherapy with S-1 shows higher efficacy than S-1 alone, and combined chemo-radiotherapy with S-1 exerts remarkable therapeutic effects. Furthermore, we should consider the combined therapy of S-1 and molecular targeting agents right now as these combinations were reportedly useful for oral cancer treatment. Here, we describe our findings related to S-1 that were obtained experimentally and clinically, and favorable therapeutic strategies with S-1 against oral cancer with bibliographic considerations.

  7. Regioselective reaction: synthesis and pharmacological study of Mannich bases containing ibuprofen moiety.

    PubMed

    Sujith, K V; Rao, Jyothi N; Shetty, Prashanth; Kalluraya, Balakrishna

    2009-09-01

    A series of 4-[(4-aryl)methylidene]amino-2-(substituted-4-ylmethyl)-5-{1-[4-(2-methylpropyl)phenyl]ethyl}-2,4-dihydro-3H-1,2,4-triazole-3-thione (6) were synthesized from an arylpropionic acid namely, ibuprofen by a three-component Mannich reaction. Aminomethylation of 4-[(4-aryl)methylidene]amino-5-{1-[4-(2-methylpropyl)phenyl] ethyl}-4H-1,2,4-triazole-3-thiol (5) with formaldehyde and a secondary amine furnished this novel series of Mannich bases (6). Both Schiff bases (5) and Mannich bases (6) were well characterized on the basis of IR, NMR, mass spectral data and elemental analysis. They were screened for their anti-inflammatory, analgesic, antibacterial and antifungal activities. Some of the Mannich bases (6) carrying morpholino and N-methylpiperazino residues were found to be promising anti-inflammatory and analgesic agents.

  8. Preparation of gold nanoparticles by surfactant-promoted reductive reaction without extra reducing agent.

    PubMed

    Tang, Junqi; Huang, Jiamin; Man, Shi-Qing

    2013-02-15

    Cetyltrimethyl ammonium bromide (CTAB) has been extensively applied in the solution-phase synthesis of many types of colloidal nanoparticles. However, the uses of CTAB were mainly considered as template or capping agents to form controllable shape and protect the product from agglomeration. Here it was discovered that CATB could serve as a very mild reductant to reduce gold salt precursors preparing gold nanoparticles (GNPs) at base environment. CTAB acted as the reducing agent suffering a partial degradation and forming CTA macro radicals. FTIR proved the formation of CCl and/or CBr bond after CTAB degraded. The characterization of synthesized GNPs was examined by UV-Vis spectra, TEM and XRD. Several factors affecting the process of reaction, such as the amount of NaOH, the molar ratio of CTAB and HAuCl(4), the reaction temperature, the effect of light and oxygen, and stirring were discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. The treatment of human cancer with agents prepared from bovine cartilage.

    PubMed

    Prudden, J F

    1985-12-01

    Oral and subcutaneous administration of specific preparations of bovine tracheal cartilage rings (Catrix), a nontoxic agent, has resulted in a high response rate in 31 cases of a variety of clinical malignancies (response rate 90%, 61% complete). The demonstrated responder include present therapeutic disasters such as glioblastoma multiforme and cancers of the pancreas and lung. Other types which were treated with success included cancers of the ovary, rectum, prostate, cervix, thyroid, and an inoperable squamous cancer of the nose. These responses were observed when full dose therapy was given over prolonged courses of treatment (years). This wide range of Catrix efficacy now invites investigation by others to confirm the effectiveness of the material and to isolate the molecular entities responsible for these unexpectedly favorable results.

  10. Persuasive Embodied Agents: Using Embodied Agents to Change People's Behavior, Beliefs, and Assessments

    ERIC Educational Resources Information Center

    Pickard, Matthew David

    2012-01-01

    Embodied Conversational Agents (i.e., avatars; ECAs) are appearing in increasingly many everyday contexts, such as e-commerce, occupational training, and airport security. Also common to a typical person's daily life is persuasion. Whether being persuaded or persuading, the ability to change another person's attitude or behavior is a…

  11. Preparation of Hybrid Nanoparticle Nucleating Agents and Their Effects on the Crystallization Behavior of Poly(ethylene terephthalate)

    PubMed Central

    Han, Zhenzhen; Wang, Yao; Wang, Jiuxing; Wang, Shichao; Zhuang, Hongwei; Liu, Jixian; Huang, Linjun; Wang, Yanxin; Wang, Wei; Belfiore, Laurence A.; Tang, Jianguo

    2018-01-01

    In this research contribution, the primary objective was to enhance the crystallization behavior of poly(ethylene terephthalate) (PET). To accomplish this tack, three kinds of new nucleating agents SiO2-diethylene glycol-LMPET (PET-3), SiO2-triethylene glycol–LMPET(PET-4) and SiO2-tetraethylene glycol-LMPET (PET-5) nucleating agents were prepared via grafting different oligomers (diethylene glycol; triethylene glycol and tetraethylene glycol) to the surface of nano-SiO2 and then linking to the low molecular weight poly(ethylene terephthalate) (LMPET). These nano-particle nucleating agents facilitated the crystallization of PET. Differential scanning calorimetry (DSC) studies of the composites that pure PET blended with PET-3, PET-4 and PET-5 indicated that the longer ethoxy segment in the nucleating agents exhibited (i) higher degrees of crystallinity; (ii) faster rates of crystallization; and (iii) higher crystallization temperatures. The Jeziorny method was employed to analyze the non-isothermal crystallization kinetics of the composites. These works demonstrated that the PET-3, PET-4 and PET-5 were attractive nucleating agents for poly(ethylene terephthalate), and the longer the chain length of the ethoxy segment in the nucleating agents, the more efficient the nucleation effect. PMID:29641456

  12. Derivatizations of Sgc8-c aptamer to prepare metallic radiopharmaceuticals as imaging diagnostic agents: Syntheses, isolations, and physicochemical characterizations.

    PubMed

    Sicco, Estefanía; Báez, Jessica; Margenat, Jimena; García, Fernanda; Ibarra, Manuel; Cabral, Pablo; Moreno, María; Cerecetto, Hugo; Calzada, Victoria

    2018-03-01

    Aptamers, oligonucleotides with the capability to bind to a target through non-covalent bonds with high affinity and specificity, have a great number of advantages as scaffold to prepare molecular imaging agents. In this sense, we have performed post-SELEX modifications of a truncated aptamer, Sgc8-c, which bind to protein tyrosine kinase 7 to obtain a specific molecular targeting probe for in vivo diagnosis and in vivo therapy. Herein, we describe the synthetic efforts to prepare conjugates between Sgc8-c and different metallic ions chelator moieties in short times, high purities, and adequate yields. The selected chelator moieties, derived from 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid, 2-benzyl-1,4,7-triazacyclononane-1,4,7-triacetic acid, and 6-hydrazinonicotinic acid, were covalently attached at the 5'-aptamer position yielding the expected products which were stable in aqueous solution up to 75°C and in typical aptamer storage conditions at least for 30 days. © 2017 John Wiley & Sons A/S.

  13. Synthetic Ni3S2/Ni hybrid architectures as potential contrast agents in MRI

    NASA Astrophysics Data System (ADS)

    Ma, J.; Chen, K.

    2016-04-01

    Traditional magnetic resonance imaging (MRI) contrast agents mainly include superparamagnetic (SPM) iron oxide nanoparticle as T 2 contrast agent for liver and paramagnetic Gd (III)-chelate as T 1 contrast agent for all organs. In this work, weak ferromagnetic kale-like and SPM cabbage-like Ni3S2@Ni hybrid architectures were synthesized and evaluated as potential T 1 MRI contrast agents. Their relatively small r 2/r 1 ratios of 2.59 and 2.38, and high r 1 values of 11.27 and 4.89 mmol-1 L s-1 (for the kale-like and cabbage-like Ni3S2@Ni, respectively) will shed some light on the development of new-type MRI contrast agents.

  14. Structure–Activity Relationship Studies of the Tricyclic Indoline Resistance-Modifying Agent

    PubMed Central

    2015-01-01

    Previously we discovered a tricyclic indoline, N-[2-(6-bromo-4-methylidene-2,3,4,4a,9,9a-hexahydro-1H-carbazol-4a-yl)ethyl]-4-chlorobenzene-1-sulfonamide (1, Of1), from bioinspired synthesis of a highly diverse polycyclic indoline alkaloid library, that selectively resensitizes methicillin-resistant Staphylococcus aureus strains to β-lactam antibiotics. Herein, we report a thorough structure–activity relationship investigation of 1, which identified regions of 1 that tolerate modifications without compromising activity and afforded the discovery of a more potent analogue with reduced mammalian toxicity. PMID:24694192

  15. Low-temperature solid-state preparation of ternary CdS/g-C3N4/CuS nanocomposites for enhanced visible-light photocatalytic H2-production activity

    NASA Astrophysics Data System (ADS)

    Cheng, Feiyue; Yin, Hui; Xiang, Quanjun

    2017-01-01

    Low-temperature solid-state method were gradually demonstrated as a high efficiency, energy saving and environmental protection strategy to fabricate composite semiconductor materials. CdS-based multiple composite photocatalytic materials have attracted increasing concern owning to the heterostructure constituents with tunable band gaps. In this study, the ternary CdS/g-C3N4/CuS composite photocatalysts were prepared by a facile and novel low-temperature solid-state strategy. The optimal ternary CdS/g-C3N4/CuS composite exhibits a high visible-light photocatalytic H2-production rate of 57.56 μmol h-1 with the corresponding apparent quantum efficiency reaches 16.5% at 420 nm with Na2S/Na2SO3 mixed aqueous solution as sacrificial agent. The ternary CdS/g-C3N4/CuS composites show the enhanced visible-light photocatalytic H2-evolution activity comparing with the binary CdS-based composites or simplex CdS. The enhanced photocatalytic activity is ascribed to the heterojunctions and the synergistic effect of CuS and g-C3N4 in promotion of the charge separation and charge mobility. This work shows that the low-temperature solid-state method is efficient and environmentally benign for the preparation of CdS-based multiple composite photocatalytic materials with enhanced visible-light photocatalytic H2-production activity.

  16. Multifunctional foaming agent to prepare aluminum foam with enhanced mechanical properties

    NASA Astrophysics Data System (ADS)

    Li, Xun; Liu, Ying; Ye, Jinwen; An, Xuguang; Ran, Huaying

    2018-03-01

    In this paper, CuSO4 was used as foaming agent to prepare close cell Aluminum foam(Al foam) at the temperature range of 680 °C ∼ 758 °C for the first time. The results show that CuSO4 has multifunctional such as, foaming, viscosity increasing, reinforcement in Al matrix, it has a wide decomposition temperature range of 641 °C ∼ 816 °C, its sustain-release time is 5.5 min at 758 °C. The compression stress and energy absorption of CuSO4-Al foam is 6.89 Mpa and 4.82 × 106 J m‑3(compression strain 50%), which are 77.12% and 99.17% higher than that of TiH2-Al foam at the same porosity(76% in porosity) due to the reinforcement in Al matrix and uniform pore dispersion.

  17. Polyurethane with Tethered Copper(II)-Cyclen Complex: Preparation, Characterization and Catalytic Generation of Nitric Oxide from S-Nitrosothiols

    PubMed Central

    Hwang, Sangyeul

    2008-01-01

    The preparation and characterization of a commercial biomedical grade polyurethane (Tecophilic, SP-93A-100) material possessing covalently linked copper(II)-cyclen moieties as a nitric oxide (NO) generating polymer are described. Chemiluminescence NO measurements demonstrate that the prepared polymer can decompose endogenous S-nitrosothiols (RSNOs) such as S-nitrosoglutathione and S-nitrosocysteine to NO in the presence of thiol reducing agents (RSHs; e.g., glutathione and cysteine) at physiological pH. Since such RSNO and RSH already exist in blood, the proposed polymer is capable of spontaneously generating NO when in contact with fresh blood. This is demonstrated by utilizing the polymer as an outer coating at the distal end of an amperometric NO sensor to create a device that generates response toward the RSNO species in the blood. This polymer possesses the combined benefits of a commercial biomedical grade polyurethane with the ability to generate biologically active NO when on contact with blood, and thus may serve as a useful coating to improve the hemocompatibility of various medical devices. PMID:18314189

  18. Preparing Students for Future Learning with Teachable Agents

    ERIC Educational Resources Information Center

    Chin, Doris B.; Dohmen, Ilsa M.; Cheng, Britte H.; Oppezzo, Marily A.; Chase, Catherine C.; Schwartz, Daniel L.

    2010-01-01

    Over the past several years, the authors have been developing an instructional technology, called Teachable Agents (TA), which draws on the social metaphor of teaching to help students learn. Students teach a computer character, their "agent," by creating a concept map of nodes connected by qualitative causal links. The authors hypothesize that…

  19. Preparing cytotoxic agents in an isolator.

    PubMed

    Favier, M; Hansel, S; Bressolle, F

    1993-11-01

    The design of an isolator and its use by an oncology satellite pharmacy for preparing cytotoxic drugs are described. The isolator (Iso Concept, Boulogne, France) is a totally enclosed ventilated biological-safety cabinet of class III polyvinyl chloride (PVC) with positive air pressure, a half-suit with a rotating seal, and attached neoprene gloves. There are three work-stations, one for the half-suit and two along one side of the isolator. The ventilation and air filtration system consists of one entry pipe with a full ventilation-filtration box fitted with one prefilter, one blower, one ball valve, one high-efficiency particulate air (HEPA) filter, one airtight nipple connected to an automatic sterilizer, alarms, and one exhaust pipe protected by a HEPA filter. The air lock consists of a rigid, transparent Plexiglas pass-through. The chamber is sterilized with heated compressed air mixed with 3.5% peracetic acid. Maintenance includes regular changing of gloves and HEPA filters; checking of the integrity of the PVC, half-suit, and gloves; and washing and decontamination procedures. Preparation of cytotoxics is planned in advance with prescription data and manufacturing sheets. In the half-suit, a pharmacy technician reads the label, supervises preparation of the sterile admixture, and writes a label. The operators on the side of the unit read the manufacturing sheet and prepare the dose identified by the label.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Preparation of a new Fenton-like catalyst from red mud using molasses wastewater as partial acidifying agent.

    PubMed

    Wei, Guangtao; Shao, Luhua; Mo, Jihua; Li, Zhongmin; Zhang, Linye

    2017-06-01

    Using molasses wastewater as partial acidifying agent, a new Fenton-like catalyst (ACRM sm ) was prepared through a simple process of acidification and calcination using red mud as main material. With molasses wastewater, both the free alkali and the chemically bonded alkali in red mud were effectively removed under the action of H 2 SO 4 and molasses wastewater, and the prepared ACRM sm was a near-neutral catalyst. The ACRM sm preparation conditions were as follows: for 3 g of red mud, 9 mL of 0.7 mol/L H 2 SO 4 plus 2 g of molasses wastewater as the acidifying agent, calcination temperature 573 K, and calcination time 1 h. Iron phase of ACRM sm was mainly α-Fe 2 O 3 and trace amount of carbon existed in ACRM sm . The addition of molasses wastewater not only effectively reduced the consumption of H 2 SO 4 in acidification of red mud but also resulted in the generation of carbon and significantly improved the distribution of macropore in prepared ACRM sm . It was found that near-neutral pH of catalyst, generated carbon, and wide distribution of macropore were the main reasons for the high catalytic activity of ACRM sm . The generated carbon and wide distribution of macropore were entirely due to the molasses wastewater added. In degradation of orange II, ACRM sm retained most of its catalytic stability and activity after five recycling times, indicating ACRM sm had an excellent long-term stability in the Fenton-like process. Furthermore, the performance test of settling showed ACRM sm had an excellent settleability. ACRM sm was a safe and green catalytic material used in Fenton-like oxidation for wastewater treatment.

  1. Should bowel preparation, antifoaming agents, or prokinetics be used before video capsule endoscopy? A systematic review and meta-analysis.

    PubMed

    Kotwal, Vikram S; Attar, Bashar M; Gupta, Saurabh; Agarwal, Rajender

    2014-02-01

    The ideal bowel preparation regime before small bowel video capsule endoscopy (VCE) is not known. We carried out a systematic review and meta-analysis to study the effect of purgatives, antifoaming agents, and prokinetics on the outcomes associated with VCE. We performed literature searches in MEDLINE and Cochrane Library and included randomized-controlled trials studying the effect of purgatives, antifoaming agents, and prokinetics in patients undergoing VCE. Our outcomes of interest were visualization quality, diagnostic yield, and completion rate. Meta-analyses were carried out using the RevMan software and heterogeneity was assessed using the I statistic. Fifteen studies fulfilled the inclusion criteria. As compared with no bowel preparation, bowel preparation with polyethylene glycol (PEG) led to adequate visualization in a significantly higher number of patients undergoing VCE [odds ratio (OR) 3.13; 95% confidence interval (CI) 1.70-5.75]. Both PEG and sodium phosphate significantly improved the diagnostic yield (OR 1.68; 95% CI 1.16-2.42 and OR 1.77; 95% CI 1.18-2.64, respectively) but did not affect the completion rate. All studies with simethicone showed significantly improved visualization quality with its use as compared with overnight fasting or purgatives alone. Prokinetics did not significantly improve the completion rate of VCE. On the basis of the data available, a combination of PEG and simethicone appears to be the best approach for small bowel preparation before VCE. However, large multicenter randomized-controlled trials are needed to validate this recommendation and to evaluate the ideal dose of PEG and timing of bowel preparation before VCE. Prokinetics administered before VCE do not improve the completion rate and should not be used.

  2. Apollo 9 crew prepares to cut cake on U.S.S. Guadalcanal

    NASA Image and Video Library

    1969-03-13

    The Apollo 9 crew prepares to cut the 350-pound cake which was baked on the U.S.S. Guadalcanal in their honor. Left to right, are Astronauts Russell L. Schweickart, David R. Scott, and James A. McDivitt. Looking on at right is Capt. Roy M. Sudduth, commanding officer of the U.S.S. Guadalcanal.

  3. Strongly luminescent monolayered MoS2 prepared by effective ultrasound exfoliation.

    PubMed

    Štengl, Václav; Henych, Jiří

    2013-04-21

    Intense ultrasound in a pressurized batch reactor was used for preparation of monolayered MoS2 nanosheets from natural mineral molybdenite. Exfoliation of bulk MoS2 using ultrasound is an attractive route to large-scale preparation of monolayered crystals. To evaluate the quality of delamination, methods like X-ray diffraction, Raman spectroscopy and microscopic techniques (TEM and AFM) were employed. From single- or few-layered products obtained from intense sonication, MoS2 quantum dots (MoSQDs) were prepared by a one-pot reaction by refluxing exfoliated nanosheets of MoS2 in ethylene glycol under atmospheric pressure. The synthesised MoSQDs were characterised by photoluminescence spectroscopy and laser-scattering particle size analysis. Our easy preparation leads to very strongly green luminescing quantum dots.

  4. Preparation of hyperbranched poly (amidoamine)-grafted graphene nanolayers as a composite and curing agent for epoxy resin

    NASA Astrophysics Data System (ADS)

    Gholipour-Mahmoudalilou, Meysam; Roghani-Mamaqani, Hossein; Azimi, Reza; Abdollahi, Amin

    2018-01-01

    Thermal properties of epoxy resin were improved by preparation of a curing agent of poly (amidoamine) (PAMAM) dendrimer-grafted graphene oxide (GO). Hyperbranched PAMAM-modified GO (GD) was prepared by a divergent dendrimer synthesis methodology. Modification of GO with (3-Aminopropyl)triethoxysilane (APTES), Michael addition of methacrylic acid, and amidation reaction with ethylenediamine results in the curing agent of GD. Then, epoxy resin was cured in the presence of different amounts of GD and the final products were compared with ethylenediamine-cured epoxy resin (E) in their thermal degradation temperature and char contents. Functionalization of GO with APTES and hyperbranched dendrimer formation at the surface of GO were evaluated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and thermogravimetric analysis (TGA) results. TGA results showed that the weight loss associated with chemical moieties in GONH2, GOMA, and GD is estimated to be 10.1, 12.2, and 14.1%, respectively. Covalent attachment of dendrimer at the surface of GO increases its thermal stability. TGA also showed that decomposition temperature and char content are higher for composites compared with E. Scanning and transmission electron microscopies show that flat and smooth graphene nanolayers are wrinkled in GO and re-stacking and flattening of nanolayers is observed in GD.

  5. Effects of complexing agents on electrochemical deposition of FeS x O y in ZnO/FeS x O y heterostructures

    NASA Astrophysics Data System (ADS)

    Supee, A.; Ichimura, M.

    2017-12-01

    Heterostructures which consist of ZnO and FeS x O y were deposited via electrochemical deposition (ECD) for application to solar cells. Galvanostatic ECD was used in FeS x O y deposition with a solution containing 100 mM Na2S2O3 and 30 mM FeSO4. To alter the film properties, L(+)-tartaric acid (C4H6O6) and lactic acid [CH3CH(OH)COOH] were introduced as the complexing agents into the FeS x O y deposition solution. Larger film thickness and smaller oxygen content were obtained for the films deposited with the complexing agents. ZnO was deposited on FeS x O y by two-step pulse ECD from a solution containing Zn(NO3)2. For the ZnO/FeS x O y heterostructures fabricated with/without complexing agents, rectifying properties were confirmed in the current density-voltage ( J- V) characteristics. However, photovoltaic properties were not improved with addition of both complexing agents.

  6. Hydroxypyridonate and hydroxypyrimidinone chelating agents

    DOEpatents

    Raymond, Kenneth N.; Doble, Daniel M.; Sunderland, Christopher J.; Thompson, Marlon

    2005-01-25

    The present invention provides hydroxypyridinone and hydroxypyrimidone chelating agents. Also provides are Gd(III) complexes of these agents, which are useful as contrast enhancing agents for magnetic resonance imaging. The invention also provides methods of preparing the compounds of the invention, as well as methods of using the compounds in magnetic resonance imaging applications.

  7. Influence of aluminium nitride as a foaming agent on the preparation of foam glass-ceramics from high-titanium blast furnace slag

    NASA Astrophysics Data System (ADS)

    Shi, Huan; Feng, Ke-qin; Wang, Hai-bo; Chen, Chang-hong; Zhou, Hong-ling

    2016-05-01

    To effectively reuse high-titanium blast furnace slag (TS), foam glass-ceramics were successfully prepared by powder sintering at 1000°C. TS and waste glass were used as the main raw materials, aluminium nitride (AlN) as the foaming agent, and borax as the fluxing agent. The influence of the amount of AlN added (1wt%-5wt%) on the crystalline phases, microstructure, and properties of the produced foam glass-ceramics was studied. The results showed that the main crystal phases were perovskite, diopside, and augite. With increasing AlN content, a transformation from diopside to augite occurred and the crystallinity of the pyroxene phases slightly decreased. Initially, the average pore size and porosity of the foam glass-ceramics increased and subsequently decreased; similarly, their bulk density and compressive strength decreased and subsequently increased. The optimal properties were obtained when the foam glass-ceramics were prepared by adding 4wt% AlN.

  8. JPRS Report, Soviet Union, Political Affairs, Preparations for the 19th Party Conference.

    DTIC Science & Technology

    1988-10-30

    Russia’s trade union movement in 1910. The secret police, whose agent he was, was preparing him for a big game. Unfortunately, it largely succeeded in... agent of the secret police department. In the fall of 1918 Malinovskiy returned to Petrograd and, after being sentenced by the All-Russian Central...structures which would give authorized agents (the workers and peasants themselves) an opportunity to inspect any documents and materials concerning

  9. 21 CFR 640.55 - U.S. Standard preparation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false U.S. Standard preparation. 640.55 Section 640.55 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Cryoprecipitate § 640.55 U.S. Standard...

  10. 21 CFR 640.55 - U.S. Standard preparation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true U.S. Standard preparation. 640.55 Section 640.55 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Cryoprecipitate § 640.55 U.S. Standard...

  11. The Curricular Indian Agent: Discursive Colonization and Indigenous (Dys)Agency in U.S. History Textbooks

    ERIC Educational Resources Information Center

    Stanton, Christine Rogers

    2014-01-01

    In the 1800s and early 1900s, the United States assigned Indian Agents--non-Native employees of the federal government--to coordinate intergovernmental efforts, to encourage the assimilation of Native peoples into European-American society, and to serve as advocates for individual tribes. Although Indian Agents no longer exist in an official…

  12. 21 CFR 172.785 - Listeria-specific bacteriophage preparation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... preparation. The additive may be safely used as an antimicrobial agent specific for Listeria monocytogenes (L... 725.421(d). No sequences derived from genes encoding bacterial 16S ribosomal RNA are present in the..., as determined by the “Method to Determine Microbial Contamination,” dated July 11, 2003, and printed...

  13. 21 CFR 172.785 - Listeria-specific bacteriophage preparation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... preparation. The additive may be safely used as an antimicrobial agent specific for Listeria monocytogenes (L... 725.421(d). No sequences derived from genes encoding bacterial 16S ribosomal RNA are present in the..., as determined by the “Method to Determine Microbial Contamination,” dated July 11, 2003, and printed...

  14. 21 CFR 172.785 - Listeria-specific bacteriophage preparation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... preparation. The additive may be safely used as an antimicrobial agent specific for Listeria monocytogenes (L... 725.421(d). No sequences derived from genes encoding bacterial 16S ribosomal RNA are present in the..., as determined by the “Method to Determine Microbial Contamination,” dated July 11, 2003, and printed...

  15. Synthesis, DFT calculations, spectroscopic and photovoltaic of the novel N″, N‴-bis[(4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromen-6-yl)methylidene] thiocarbonohydrazide (BFCMT) and its photodiode application

    NASA Astrophysics Data System (ADS)

    Farag, A. A. M.; Ibrahim, Magdy A.; Halim, Shimaa Abdel; Roushdy, N.; El-Gohary, Nasser M.

    2018-03-01

    Condensation reaction of 6-formylkhellin (1) with thiocarbohydrazide in 2:1 M ratio afforded the novel N″, N‴-bis [(4, 9-dimethoxy-5-oxo-5H-furo [3,2-g]chromen-6-yl) methylidene]thiocarbonohydrazide (BFCMT) and its electronic absorption spectrum was interpreted by TD-DFT calculations. The electronic transition is direct allowed with onset and fundamental energy gaps of 1.06 and 3.36 eV, respectively. The estimated optical constants were applied to evaluate the optical transition type as well as the effective optical parameters. The current density-voltage characteristics of BFCMT/p-Si heterojunction at 300 K in dark and under illumination of 100 mW/cm2 showed rectifying characteristics. The capacitance-voltage characteristic parameters under illumination showed a reduction in the built-in potential and increasing the active carrier concentration. The loaded J-V characteristics of BFCMT/p-Si heterojunction under illumination were investigated and showed a remarkable power conversion efficiency of 0.83% without consideration of the refection correction or losses from the upper electrode absorption.

  16. Inverse supercritical fluid extraction as a sample preparation method for the analysis of the nanoparticle content in sunscreen agents.

    PubMed

    Müller, David; Cattaneo, Stefano; Meier, Florian; Welz, Roland; de Vries, Tjerk; Portugal-Cohen, Meital; Antonio, Diana C; Cascio, Claudia; Calzolai, Luigi; Gilliland, Douglas; de Mello, Andrew

    2016-04-01

    We demonstrate the use of inverse supercritical carbon dioxide (scCO2) extraction as a novel method of sample preparation for the analysis of complex nanoparticle-containing samples, in our case a model sunscreen agent with titanium dioxide nanoparticles. The sample was prepared for analysis in a simplified process using a lab scale supercritical fluid extraction system. The residual material was easily dispersed in an aqueous solution and analyzed by Asymmetrical Flow Field-Flow Fractionation (AF4) hyphenated with UV- and Multi-Angle Light Scattering detection. The obtained results allowed an unambiguous determination of the presence of nanoparticles within the sample, with almost no background from the matrix itself, and showed that the size distribution of the nanoparticles is essentially maintained. These results are especially relevant in view of recently introduced regulatory requirements concerning the labeling of nanoparticle-containing products. The novel sample preparation method is potentially applicable to commercial sunscreens or other emulsion-based cosmetic products and has important ecological advantages over currently used sample preparation techniques involving organic solvents. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Preparation of mesoporous titanium dioxide anode by a film- and pore-forming agent for the dye-sensitized solar cell

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hou, Wenjing; Xiao, Yaoming, E-mail: ymxiao@sxu.edu.cn; Han, Gaoyi, E-mail: han_gaoyis@sxu.edu.cn

    2016-04-15

    Highlights: • PVP is used as a film- and pore-forming agent to prepare the mesoporous TiO{sub 2} anode. • The TiO{sub 2} anode supplies high surface area for the dye adsorption. • The DSSC efficiency is strongly dependent on the pore properties of the TiO{sub 2} anode. • The DSSC efficiency with the TiO{sub 2} anode prepared by 20 wt% PVP reaches 8.39%. - Abstract: A novel mean of generating mesoporous titanium dioxide (TiO{sub 2}) anodes by employing polyvinylpyrrolidone (PVP) as the film- and pore-forming agent are proposed for dye-sensitized solar cells (DSSCs). The influences on the morphology and photovoltaicmore » performances of the TiO{sub 2} anodes are investigated by adjusting the PVP content in synthesizing the mesoporous TiO{sub 2} anodes. The photovoltaic conversion efficiency of the DSSC is found to be strongly dependent on the pore properties of the TiO{sub 2} anode. After the sintering process, the removal of the PVP leaves porously interconnected channel structures inside the TiO{sub 2} anode, supplying enhanced specific surface area for the dye adsorption as well as the efficient electron transmission. As a result, the TiO{sub 2} anode prepared by 20 wt% PVP presents the highest performances, based on which the DSSC achieves the highest conversion efficiency of 8.39%, approximately increased by 56.53% than that of the DSSC fabricated without PVP (5.36%).« less

  18. N and S co-doped porous carbon spheres prepared using L-cysteine as a dual functional agent for high-performance lithium-sulfur batteries.

    PubMed

    Niu, Shuzhang; Lv, Wei; Zhou, Guangmin; He, Yanbing; Li, Baohua; Yang, Quan-Hong; Kang, Feiyu

    2015-12-28

    Nitrogen and sulfur co-doped porous carbon spheres (NS-PCSs) were prepared using L-cysteine to control the structure and functionalization during the hydrothermal reaction of glucose and the subsequent activation process. As the sulfur hosts in Li-S batteries, NS-PCSs combine strong physical confinement and surface chemical interaction to improve the affinity of polysulfides to the carbon matrix.

  19. Dephosphorylation of receptor tyrosine kinases as target of regulation by radiation, oxidants or alkylating agents.

    PubMed Central

    Knebel, A; Rahmsdorf, H J; Ullrich, A; Herrlich, P

    1996-01-01

    Several non-physiologic agents such as radiation, oxidants and alkylating agents induce ligand-independent activation of numerous receptor tyrosine kinases (RTKs) and of protein tyrosine kinases at the inner side of the plasma membrane (e.g. Dévary et al., 1992; Sachsenmaier et al., 1994; Schieven et al., 1994; Coffer et al., 1995). Here we show additional evidence for the activation of epidermal growth factor receptor (EGFR), and we show activation of v-ErbB, ErbB2 and platelet-derived growth factor receptor. As a common principle of action the inducing agents such as UVC, UVB, UVA, hydrogen peroxide and iodoacetamide inhibit receptor tyrosine dephosphorylation in a thiol-sensitive and, with the exception of the SH-alkylating agent, reversible manner. EGFR dephosphorylation can also be modulated by these non-physiologic agents in isolated plasma membranes in the presence of Triton X-100. Further, substrate (EGFR) and phosphatase have been separated: a membrane preparation of cells that have been treated with epidermal growth factor (EGF) and whose dephosphorylating enzymes have been permanently destroyed by iodoacetamide can be mixed with a membrane preparation from untreated cells which re-establishes EGFR dephosphorylation. This dephosphorylation can be modulated in vitro by UV and thiol agents. We conclude that RTKs exhibit significant spontaneous protein kinase activity; several adverse agents target (an) essential SH-group(s) carried by (a) membrane-bound protein tyrosine phosphatase(s). Images PMID:8895576

  20. Effect of preparation methods and doping on the structural and tunable emissions of CdS

    NASA Astrophysics Data System (ADS)

    Mohamed, Mohamed Bakr; Abdel-Kader, M. H.; Alhazime, Ali A.; Almarashi, Jamal Q. M.

    2018-03-01

    Fe, Mn and Mg doped CdS samples were prepared by thermolysis method in air and under flow of nitrogen. Structural, compositional and optical properties of the prepared samples were investigated using x-ray powder diffraction (XRD), scanning electron microscope (SEM/EDS mapping), Fourier transform infrared red (FTIR), UV-vis absorption and photoluminescence (PL) spectroscopes. Rietveld refinement of x-ray data showed that all the undoped and doped CdS samples prepared in air and under flow of nitrogen have both cubic and hexagonal structures. The percentages of hexagonal and cubic phases for all prepared samples were determined. The crystallite size increased for CdS prepared under flow of N2 compared with the sample prepared in air. The energy gap of all the samples was calculated using UV data. The intensity of PL emission changed according to the method of preparation and the kind of doping elements. PL emission revealed a blue shift for CdS prepared in air compared with CdS prepared under flow of nitrogen; also all doped samples showed a red shift of PL spectra compared with undoped samples. Undoped and doped CdS with Fe and Mg samples emitted violet and blue sub-spectra. Mn doped CdS prepared in air revealed violet, blue and yellow sub-spectra, while the sample prepared under flow of N2 emitted violet, blue and green sub-spectra.

  1. Preparation and in vitro evaluation of poly(D,L-lactide-co-glycolide) air-filled nanocapsules as a contrast agent for ultrasound imaging.

    PubMed

    Néstor, Mendoza-Muñoz; Kei, Noriega-Peláez Eddy; Guadalupe, Nava-Arzaluz María; Elisa, Mendoza-Elvira Susana; Adriana, Ganem-Quintanar; David, Quintanar-Guerrero

    2011-10-01

    The aim of this study was to prepare air-filled nanocapsules intended ultrasound contrast agents (UCAs) with a biodegradable polymeric shell composed of poly(d,l-lactide-co-glycolide) (PLGA). Because of their size, current commercial UCAs are not capable of penetrating the irregular vasculature that feeds growing tumors. The new generation of UCAs should be designed on the nanoscale to enhance tumor detection, in addition, the polymeric shell in contrast with monomolecular stabilized UCAs improves the mechanical properties against ultrasound pressure and lack of stability. The preparation method of air-filled nanocapsules was based on a modification of the double-emulsion solvent evaporation technique. Air-filled nanocapsules with a mean diameter of 370±96nm were obtained. Electronic microscopies revealed spherical-shaped particles with smooth surfaces and a capsular morphology, with a shell thickness of ∼50nm. Air-filled nanocapsules showed echogenic power in vitro, providing an enhancement of up to 15dB at a concentration of 0.045mg/mL at a frequency of 10MHz. Loss of signal for air-filled nanocapsules was 2dB after 30min, suggesting high stability. The prepared contrast agent in this work has the potential to be used in ultrasound imaging. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Preparation of (S)-1-Halo-2-octanols Using Ionic Liquids and Biocatalysts.

    PubMed

    Oromí-Farrús, Mireia; Eras, Jordi; Sala, Núria; Torres, Mercè; Canela, Ramon

    2009-10-23

    Preparation of (S)-1-chloro-2-octanol and (S)-1-bromo-2-octanol was carried out by the enzymatic hydrolysis of halohydrin palmitates using biocatalysts. Halohydrin palmitates were prepared by various methods from palmitic acid and 1,2-octanediol. A tandem hydrolysis was carried out using lipases from Candida antarctica (Novozym 435), Rhizomucor miehei (Lipozyme IM), and "resting cells" from a Rhizopus oryzae strain that was not mycotoxigenic. The influence of the enzyme and the reaction medium on the selective hydrolysis of isomeric mixtures of halohydrin esters is described. Novozym 435 allowed preparation of (S)-1-chloro-2-octanol and (S)-1-bromo-2-octanol after 1-3 h of reaction at 40 degrees C in [BMIM][PF(6)].

  3. Forest Service special agents, assistant special agents in charge, senior special agents, and supervisory special agents report: nationwide study

    Treesearch

    Deborah J. Chavez; Joanne F. Tynon

    2007-01-01

    This is the fourth in a series of studies to evaluate perceptions of U.S. Department of Agriculture Forest Service law enforcement personnel of the roles, responsibilities, and issues related to their jobs. An e-mail survey was administered to the 89 Forest Service special agents, assistant special agents in charge, senior special agents, and supervisory special agents...

  4. Antimicrobial salicylaldehyde Schiff bases: synthesis, characterization and evaluation.

    PubMed

    Adeel-Sharif, Hafiz Muhammad; Ahmed, Dildar; Mir, Hira

    2015-03-01

    As the pathogens soon develop resistance to the existing antibiotics, the demand for new and more effective anti-microbial agents is a continuous phenomenon. In this paper we are reporting synthesis and spectral data of eight Schiff bases of salicylaldehyde with different amines, and evaluation of their anti-microbial activities against different bacterial strains. The bases were synthesized by reflux method, and their structures were determined based FT-IR, (1)H-NMR, (13)C-NMR and Mass spectrometric data. The Schiff bases synthesized included 2-{[(Z)-(2-hydroxyphenyl) methylidene] amino}benzoicacid (SB1), 4-{[(Z)-(2-hydroxyphenyl) methylidene] amino} benzoic acid (SB2),2-[(naphthalene-2-ylimino)methyl] phenol(SB3),2-2'-[benzene-1,4-diylbis(nitrilomethylylidene)]diphenol (SB4), 2-2'-[benzene-1,2-diylbis (nitrile-(E)-methylylidene)]diphenol (SB5), 2-[(2-phenylhydrazineylidene)methyl]phenol (SB6), 2-2'-[ethene-1,2-diylbis(iminomethanediyl)]diphenol (SB7) and 2-[(Z)-(phenylimino)methyl]phenol (SB8). The anti-microbial activities of synthesized Schiff bases were determined in terms of zones of inhibition and minimum inhibitory concentrations (MICs). All the bases showed moderate to good activities against all the tested microorganisms. The MICs of most compounds were 100-200βg/mL against different microorganisms. However, it was 50βg/mL for SB1 against P. aeruginosa (1), SB3 against P. aurantiaca, P. aeruginosa (1), E. coli (2), S. typhi (2) and C. freundii, SB4against E. coli (2), S. typhi (1) and S. maltophilia, SB5 against K. pneumoniae and S. typhi (2), SB6 against P. aeruginosa (3) and C. freundii, SB7 against E. cloacae and A. lipoferum, and SB8 against E. coli (2). Considerably active bases may prove to be potential candidates for future antibiotic drugs.

  5. Poly(ethylene glycol)s as grinding additives in the mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins.

    PubMed

    Mascitti, Andrea; Lupacchini, Massimiliano; Guerra, Ruben; Taydakov, Ilya; Tonucci, Lucia; d'Alessandro, Nicola; Lamaty, Frederic; Martinez, Jean; Colacino, Evelina

    2017-01-01

    The mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins was investigated in the presence of various poly(ethylene) glycols (PEGs), as safe grinding assisting agents (liquid-assisted grinding, LAG). A comparative study under dry-grinding conditions was also performed. The results showed that the cyclization reaction was influenced by the amount of the PEG grinding agents. In general, cleaner reaction profiles were observed in the presence of PEGs, compared to dry-grinding procedures.

  6. Synthesis of novel (2R,4R)- and (2S,4S)-iso dideoxynucleosides with exocyclic methylene as potential antiviral agents.

    PubMed

    Yoo, Su Jeong; Kim, Hea Ok; Lim, Yoongho; Kim, Jeongmin; Jeong, Lak Shin

    2002-01-01

    Novel (2R,4R)- and (2S,4S)-iso dideoxynucleosides with exocyclic methylene have been designed and synthesized, based on the lead BMS-200475 (3) which exhibited potent anti-HBV activity. For the synthesis of D types of (2R,4R)-nucleosides, L-xylose was converted to the key intermediate 14. The intermediate 14 was converted to the uracil derivative 4a and the cytosine derivative 4b. Compound 14 was also converted to the purine derivatives such as adenine derivative 4c, hypoxanthine derivative 4d, and guanine derivative 4e. The corresponding L types of (2S,4S)-enantiomers were more efficiently synthesized from the commercially available 1,2-isopropylidene-D-xylose (20) than the synthetic method used in the synthesis of (2R,4R)-nucleosides. The key intermediate 25 was converted to the pyrimidine analogues 5a and 5b and the purine derivatives 5c, 5d, and 5e using the similar method used in the preparation of 4c, 4d, and 4e. The synthesized final (2R,4R)- and (2S,4S)-nucleosides were tested against several viruses such as HIV-1, HSV-1, HSV-2, HCMV and HBV. (2R,4R)-Adenine analogue 4c exhibited potent anti-HBV activity (EC(50)=1.5 microM in 2.2.15 cells) among compounds tested, while (2R,4R)-uracil derivative 4a was the most active against HCMV among compounds tested and (2R,4R)-adenine derivative 4c was found to be moderately active against the same virus. However, the corresponding (2S,4S)-isomers were found to be totally inactive against all tested viruses. Both (2R,4R)-adenine derivative 4c and (2S,4S)-adenine analogue 5c were totally resistant to the adenosine deaminase like iso-ddA (1). From the molecular modeling study the hydroxymethyl side chains of BMS-200475 (3) and 4c were almost overlapped, indicating that 4c may be suitable for phosphorylation by cellular kinases like the lead 3, but some discrepancy between two bases was observed, indicating why 4c is less potent against HBV than 3. It is concluded that discovery of (2R,4R)-adenine analogue 4c as potent

  7. MoS2 thin films prepared by sulfurization

    NASA Astrophysics Data System (ADS)

    Sojková, M.; Chromik, Å.; Rosová, A.; Dobročka, E.; Hutár, P.; Machajdík, D.; Kobzev, A. P.; Hulman, M.

    2017-08-01

    Sulfurization of a Mo layer is one of the most used methods for preparation of thin MoS2 films. In the method, a sulfur powder and Mo covered substrate are placed in different positions within a furnace, and heated separately. This requires a furnace having at least two zones. Here, we present a simplified version of the method where a one-zone tube furnace was used. A molybdenum film on a substrate and a sulfur powder were placed in the center of the furnace and heated at temperatures above 800°C. Mo films transform into MoS2 in vapors of sulphur at high temperatures. As-prepared films were characterized by number of techniques including X-ray diffraction (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM), Raman, Rutherford backscattering (RBS) and X-ray photoelectron spectroscopy (XPS). It appears that one-zone sulfurization, with just one annealing temperature used, is a suitable method for fabrication of MoS2 thin films. This method is fast, cheap and easy to scale up.

  8. Veg-03 Pillows Preparation for Flight

    NASA Image and Video Library

    2016-03-21

    Inside a laboratory in the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida, research scientists prepare the plant pillows for the Veg-03 experiment that will be delivered to the International Space Station aboard the eighth SpaceX Dragon commercial resupply mission. Dr. Mathew Mickens, a post-doctoral researcher, inserts a bonding agent into one of the Veg-03 plant pillows. The Veg-03 plant pillows will contain ‘Tokyo Bekana’ cabbage seeds and lettuce seeds for NASA’s third Veggie plant growth system experiment. The experiment will continue NASA’s deep space plant growth research to benefit the Earth and the agency’s journey to Mars.

  9. Veg-03 Pillows Preparation for Flight

    NASA Image and Video Library

    2016-03-21

    Inside a laboratory in the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida, plant pillows for the Veg-03 experiment are prepared for delivery to the International Space Station aboard the eighth SpaceX Dragon commercial resupply mission. Dr. Mathew Mickens, a post-doctoral researcher, inserts a bonding agent into one of the Veg-03 plant pillows. The Veg-03 plant pillows will contain ‘Tokyo Bekana’ cabbage seeds and lettuce seeds for NASA’s third Veggie plant growth system experiment. The experiment will continue NASA’s deep space plant growth research to benefit the Earth and the agency’s journey to Mars.

  10. Biomaterials for mediation of chemical and biological warfare agents.

    PubMed

    Russell, Alan J; Berberich, Jason A; Drevon, Geraldine F; Koepsel, Richard R

    2003-01-01

    Recent events have emphasized the threat from chemical and biological warfare agents. Within the efforts to counter this threat, the biocatalytic destruction and sensing of chemical and biological weapons has become an important area of focus. The specificity and high catalytic rates of biological catalysts make them appropriate for decommissioning nerve agent stockpiles, counteracting nerve agent attacks, and remediation of organophosphate spills. A number of materials have been prepared containing enzymes for the destruction of and protection against organophosphate nerve agents and biological warfare agents. This review discusses the major chemical and biological warfare agents, decontamination methods, and biomaterials that have potential for the preparation of decontamination wipes, gas filters, column packings, protective wear, and self-decontaminating paints and coatings.

  11. Achieving the best bowel preparation for colonoscopy

    PubMed Central

    Parra-Blanco, Adolfo; Ruiz, Alex; Alvarez-Lobos, Manuel; Amorós, Ana; Gana, Juan Cristóbal; Ibáñez, Patricio; Ono, Akiko; Fujii, Takahiro

    2014-01-01

    Bowel preparation is a core issue in colonoscopy, as it is closely related to the quality of the procedure. Patients often find that bowel preparation is the most unpleasant part of the examination. It is widely accepted that the quality of cleansing must be excellent to facilitate detecting neoplastic lesions. In spite of its importance and potential implications, until recently, bowel preparation has not been the subject of much study. The most commonly used agents are high-volume polyethylene glycol (PEG) electrolyte solution and sodium phosphate. There has been some confusion, even in published meta-analyses, regarding which of the two agents provides better cleansing. It is clear now that both PEG and sodium phosphate are effective when administered with proper timing. Consequently, the timing of administration is recognized as one of the central factors to the quality of cleansing. The bowel preparation agent should be administered, at least in part, a few hours in advance of the colonoscopy. Several low volume agents are available, and either new or modified schedules with PEG that usually improve tolerance. Certain adjuvants can also be used to reduce the volume of PEG, or to improve the efficacy of other agents. Other factors apart from the choice of agent can improve the quality of bowel cleansing. For instance, the effect of diet before colonoscopy has not been completely clarified, but an exclusively liquid diet is probably not required, and a low-fiber diet may be preferable because it improves patient satisfaction and the quality of the procedure. Some patients, such as diabetics and persons with heart or kidney disease, require modified procedures and certain precautions. Bowel preparation for pediatric patients is also reviewed here. In such cases, PEG remains the most commonly used agent. As detecting neoplasia is not the main objective with these patients, less intensive preparation may suffice. Special considerations must be made for patients

  12. Agonist and antagonist actions of antipsychotic agents at 5-HT1A receptors: a [35S]GTPgammaS binding study.

    PubMed

    Newman-Tancredi, A; Gavaudan, S; Conte, C; Chaput, C; Touzard, M; Verrièle, L; Audinot, V; Millan, M J

    1998-08-21

    Recombinant human (h) 5-HT1A receptor-mediated G-protein activation was characterised in membranes of transfected Chinese hamster ovary (CHO) cells by use of guanosine-5'-O-(3-[35S]thio)-triphosphate ([35S]GTPgammaS binding). The potency and efficacy of 21 5-HT receptor agonists and antagonists was determined. The agonists, 5-CT (carboxamidotryptamine) and flesinoxan displayed high affinity (subnanomolar Ki values) and high efficacy (Emax > 90%, relative to 5-HT = 100%). In contrast, ipsapirone, zalospirone and buspirone displayed partial agonist activity. EC50s for agonist stimulation of [35S]GTPgammaS binding correlated well with Ki values from competition binding (r = +0.99). Among the compounds tested for antagonist activity, methiothepin and (+)butaclamol exhibited 'inverse agonist' behaviour, inhibiting basal [35S]GTPgammaS binding. The actions of 17 antipsychotic agents were investigated. Clozapine and several putatively 'atypical' antipsychotic agents, including ziprasidone, quetiapine and tiospirone, exhibited partial agonist activity and marked affinity at h5-HT1A receptors, similar to their affinity at hD2 dopamine receptors. In contrast, risperidone and sertindole displayed low affinity at h5-HT1A receptors and behaved as 'neutral' antagonists, inhibiting 5-HT-stimulated [35S]GTPgammaS binding. Likewise the 'typical' neuroleptics, haloperidol, pimozide, raclopride and chlorpromazine exhibited relatively low affinity and 'neutral' antagonist activity at h5-HT1A receptors with Ki values which correlated with their respective Kb values. The present data show that (i) [35S]GTPgammaS binding is an effective method to evaluate the efficacy and potency of agonists and antagonists at recombinant human 5-HT1A receptors. (ii) Like clozapine, several putatively 'atypical' antipsychotic drugs display balanced serotonin h5-HT1A/dopamine hD2 receptor affinity and partial agonist activity at h5-HT1A receptors. (iii) Several 'typical' and some putatively 'atypical

  13. 75 FR 14539 - Furnishing Identifying Number of Tax Return Preparer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-26

    ..., certified public accountants, enrolled agents, as well as tax return preparers who pass a minimum competency... obtain a PTIN, an individual must be an attorney, certified public accountant, enrolled agent, or..., certified public accountant, enrolled agent, or registered tax return preparer authorized to practice before...

  14. Poly(ethylene glycol)s as grinding additives in the mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins

    PubMed Central

    Guerra, Ruben; Taydakov, Ilya; Tonucci, Lucia; d’Alessandro, Nicola; Lamaty, Frederic; Martinez, Jean

    2017-01-01

    The mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins was investigated in the presence of various poly(ethylene) glycols (PEGs), as safe grinding assisting agents (liquid-assisted grinding, LAG). A comparative study under dry-grinding conditions was also performed. The results showed that the cyclization reaction was influenced by the amount of the PEG grinding agents. In general, cleaner reaction profiles were observed in the presence of PEGs, compared to dry-grinding procedures. PMID:28179944

  15. Ulcer Prevention Effect Of 3,4,5-Tihydroxy-N0-[(2-Methyl-1H-Indol-3yl)Methylidene]Benzohydrazide In HCl/Ethanol-Induced Gastric Mucosal Damage In Rats.

    PubMed

    Tayeby, Faezeh; Salman, Abbas Abdul Ameer; Kamran, Sareh; Khaing, Si Lay; Salehen, Nur'ain Binti; Mohan, Gokula Mohan A/L Duchiyanda

    2017-01-01

    The newly synthesized, 3,4,5-Trihydroxy-N 0-[(2-methyl-1H-indol-3-yl)-methylidene] benzohydrazide (TIBH), is an indole and gallic acid derivative. The aim of this research investigation was to evaluate the acute toxicity and the ulcer prevention potential of TIBH in HCl/Ethanol-induced gastric ulcer rat model. Six groups of rats were orally received 5ml/kg of vehicle (1 % Carboxy methyl cellulose) for the normal and ulcer control groups each, Omeprazole (20mg/kg) for positive control, 50 mg/kg, 100 mg/kg and 200 mg/kg of TIBH for experimental groups, respectively. After one hour, instead of rats in the normal group which received 5ml/kg of 1% CMC, other groups received 5ml/kg of HCl/Ethanol. All rats were sacrificed after one additional hour. Gastric juice, gastric mucosa, morphologies of gastric ulcers and protein expressions of both control and treatment groups were evaluated. TIBH showed a ulcer prevention potential by increase of the mucus secretion, decrease of the gastric acidity, up-regulation of HSP70 protein, down-regulation of Bax protein, decrease of the lipid peroxidation and the increase of the Superoxide dismutase (SOD) activity in gastric tissue homogenate. Acute toxicity assay exposed valuable information on the safety of this compound. TIBH had a dose dependent ulcer prevention potential against HCl/Ethanol-triggered gastric ulcer.

  16. Ulcer Prevention Effect Of 3,4,5-Tihydroxy-N0-[(2-Methyl-1H-Indol-3yl)Methylidene]Benzohydrazide In HCl/Ethanol-Induced Gastric Mucosal Damage In Rats

    PubMed Central

    Tayeby, Faezeh; Salman, Abbas Abdul Ameer; Kamran, Sareh; Khaing, Si Lay; Salehen, Nur'ain Binti; Mohan, Gokula Mohan A/L Duchiyanda

    2017-01-01

    The newly synthesized, 3,4,5-Trihydroxy-N 0-[(2-methyl-1H-indol-3-yl)-methylidene] benzohydrazide (TIBH), is an indole and gallic acid derivative. The aim of this research investigation was to evaluate the acute toxicity and the ulcer prevention potential of TIBH in HCl/Ethanol-induced gastric ulcer rat model. Six groups of rats were orally received 5ml/kg of vehicle (1 % Carboxy methyl cellulose) for the normal and ulcer control groups each, Omeprazole (20mg/kg) for positive control, 50 mg/kg, 100 mg/kg and 200 mg/kg of TIBH for experimental groups, respectively. After one hour, instead of rats in the normal group which received 5ml/kg of 1% CMC, other groups received 5ml/kg of HCl/Ethanol. All rats were sacrificed after one additional hour. Gastric juice, gastric mucosa, morphologies of gastric ulcers and protein expressions of both control and treatment groups were evaluated. TIBH showed a ulcer prevention potential by increase of the mucus secretion, decrease of the gastric acidity, up-regulation of HSP70 protein, down-regulation of Bax protein, decrease of the lipid peroxidation and the increase of the Superoxide dismutase (SOD) activity in gastric tissue homogenate. Acute toxicity assay exposed valuable information on the safety of this compound. TIBH had a dose dependent ulcer prevention potential against HCl/Ethanol-triggered gastric ulcer. PMID:29200945

  17. Oxidizer gels for detoxification of chemical and biological agents

    DOEpatents

    Hoffman, Dennis M.; McGuire, Raymond R.

    2002-01-01

    A gel composition containing oxidizing agents and thickening or gelling agents is used to detoxify chemical and biological agents by application directly to a contaminated area. The gelling agent is a colloidal material, such as silica, alumina, or alumino-silicate clays, which forms a viscous gel that does not flow when applied to tilted or contoured surfaces. Aqueous or organic solutions of oxidizing agents can be readily gelled with less than about 30% colloidal material. Gel preparation is simple and suitable for field implementation, as the gels can be prepared at the site of decontamination and applied quickly and uniformly over an area by a sprayer. After decontamination, the residue can be washed away or vacuumed up for disposal.

  18. In situ capping for size control of monochalcogenides (ZnS, CdS, and SnS) nanocrystals produced by anaerobic metal-reducing bacteria

    DOE PAGES

    Jang, Gyoung Gug; Jacobs, Christopher B.; Ivanov, Ilia N.; ...

    2015-07-24

    Metal monochalcogenide quantum dot nanocrystals of ZnS, CdS and SnS were prepared by anaerobic, metal-reducing bacteria using in situ capping by oleic acid or oleylamine. Furthermore, the capping agent preferentially adsorbs on the surface of the nanocrystal, suppressing the growth process in the early stages, thus leading to production of nanocrystals with a diameter of less than 5 nm.

  19. Preparation of carbon fiber unsaturated sizing agent for enhancing interfacial strength of carbon fiber/vinyl ester resin composite

    NASA Astrophysics Data System (ADS)

    Jiao, Weiwei; Cai, Yemeng; Liu, Wenbo; Yang, Fan; Jiang, Long; Jiao, Weicheng; Wang, Rongguo

    2018-05-01

    The practical application of carbon fiber (CF) reinforced vinyl ester resin (VE) composite was hampered seriously by the poor interfacial adhesion property. In this work, a novel unsaturated sizing agent was designed and prepared to improve the interfacial strength by covalently bonding CF with VE matrix. The main component of the sizing agent, N-(4‧4-diaminodiphenyl methane)-2-hydroxypropyl methacrylate (DMHM), was synthesized and confirmed by FTIR and NMR. XPS results of sized carbon fiber (SCF) showed that DMHM has adhered to desized fiber surface and reacted with some active functional groups on the surface. The SCF was characterized by high surface roughness and surface energy (especially the polar component), which means better wettability by VE. As a result, the interface shear strength and interlaminar shear strength of SCF/VE composite were enhanced by 96.56% and 66.07% respectively compared with CF/VE composite, benefited mainly from the strong and tough interphase.

  20. Preparation and Characterization of Ion-Irradiated Nanodiamonds as Photoacoustic Contrast Agents.

    PubMed

    Fang, Chia-Yi; Chang, Cheng-Chun; Mou, Chung-Yuan; Chang, Huan-Cheng

    2015-02-01

    Highly radiation-damaged or irradiated nanodiamonds (INDs) are a new type of nanomaterial developed recently as a potential photoacoustic (PA) contrast agent for deep-tissue imaging. This work characterized in detail the photophysical properties of these materials prepared by ion irradiation of natural diamond powders using various spectroscopic methods. For 40-nm NDs irradiated with 40-keV He+ at a dose of 3 x 10(15) ions/cm2, an average molar extinction coefficient of 4.2 M-1 cm-1 per carbon atom was measured at 1064 nm. Compared with gold nanorods of similar dimensions (10 nm x 67 nm), the INDs have a substantially smaller (by > 4 orders of magnitude) molar extinction coefficient per particle. However, the deficit is readily compensated by the much higher thermal stability, stronger hydrophilic interaction with water, and a lower nanobubble formation threshold (~30 mJ/cm2) of the sp3-carbon-based nanomaterial. No sign of photodamage was detected after high-energy (>100 mJ/cm2) illumination of the INDs for hours. Cell viability assays at the IND concentration of up to 100 µg/mL showed that the nanomaterial is non-cytotoxic and potentially useful for long-term PA bioimaging applications.

  1. Properties and characterization of agar/CuNP bionanocomposite films prepared with different copper salts and reducing agents.

    PubMed

    Shankar, Shiv; Teng, Xinnan; Rhim, Jong-Whan

    2014-12-19

    Various types of agar-based bio-nanocomposite (BNC) films were prepared by blending agar and six different copper nanoparticles (CuNPs) with different shapes and sizes obtained from three different sources of copper salts and two different reducing agents. The BNC films were characterized by UV-visible, FE-SEM, FT-IR, and XRD. The thermogravimetric study showed that the melting point of BNC films was increased when ascorbic acid was used as a reducing agent for CuNPs synthesis. Apparent surface color and transmittance of agar film was greatly influenced by the reinforcement of CuNPs. However, mechanical and water vapor barrier properties did not change significantly (p>0.05) by blending with CuNPs. Tensile modulus and tensile strength decreased slightly for all types of CuNPs reinforced while elongation at break slightly increased when CuNPs produced by ascorbic acid were blended. The agar bio-nanocomposite films showed profound antibacterial activity against both Gram-positive and Gram-negative food-borne pathogenic bacteria. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Re-Examining of Moffitt’s Theory of Delinquency through Agent Based Modeling

    PubMed Central

    Leaw, Jia Ning; Ang, Rebecca P.; Huan, Vivien S.; Chan, Wei Teng; Cheong, Siew Ann

    2015-01-01

    Moffitt’s theory of delinquency suggests that at-risk youths can be divided into two groups, the adolescence- limited group and the life-course-persistent group, predetermined at a young age, and social interactions between these two groups become important during the adolescent years. We built an agent-based model based on the microscopic interactions Moffitt described: (i) a maturity gap that dictates (ii) the cost and reward of antisocial behavior, and (iii) agents imitating the antisocial behaviors of others more successful than themselves, to find indeed the two groups emerging in our simulations. Moreover, through an intervention simulation where we moved selected agents from one social network to another, we also found that the social network plays an important role in shaping the life course outcome. PMID:26062022

  3. Copper sulfide nanodisk as photoacoustic contrast agent for ovarian tumor detection

    NASA Astrophysics Data System (ADS)

    Wang, Junxin; Hsu, Su-Wen; Tao, Andrea R.; Jokerst, Jesse V.

    2017-03-01

    Ultrasound is broadly used in the clinics yet is limited in early cancer detection because of its poor contrast between healthy and diseased tissues. Photoacoustic imaging can improve this limitation and has been extensively studied in pre-clinical models. Contrast agents can help improve the accuracy of diagnosis. We recently reported a novel copper sulfide (CuS) nanodisk with strong directionally-localized surface plasmon resonance in the near infrared region. This plasmonic resonance of nanodisks is tunable by changing the size and aspect ratio of CuS nanodisk. Here, we demonstrate this CuS nanodisk is a strong photoacoustic contrast agent. We prepared CuS nanodisks via a solvent-based synthesis followed by surface modification of poly(ethylene glycol) methyl ether thiol for in vivo applications. These CuS nanodisks can be detected at a concentration as low as 26 pM at 920 nm. Their nanosize and strong photoacoustic response make this novel CuS nanodisk a strong candidate for photoacoustic cancer imaging.

  4. Soil and Water – What is Detectable through Microbiological Sample Preparation Techniques

    EPA Science Inventory

    The concerns of a potential terrorist’s use of biological agents in soil and ground water are articulated by comparisons to major illnesses in this Country involving contaminated drinking water sources. Objectives are focused on the importance of sample preparation in the rapid, ...

  5. Synthesis, electrochemical, structural, spectroscopic and biological activities of mixed ligand copper (II) complexes with 2-{[(Z)-(5-bromo-2-hydroxyphenyl)methylidene]amino}benzoic acid and nitrogenous bases

    NASA Astrophysics Data System (ADS)

    Choudhary, Mukesh; Patel, R. N.; Rawat, S. P.

    2014-02-01

    Three new copper (II) complexes viz. [Cu(L1)(bipy)]ṡ2H2O 1, [Cu(L1)(dmp)]ṡCH3CN 2, [Cu(L1)(phen)] 3 where L1H2 = 2-{[(Z)-(5-bromo-2-hydroxyphenyl)methylidene]amino}benzoic acid, bipy = 2,2‧-bipyridine; dmp = 2,9-dimethyl 1,10-phenanthroline, phen = 1,10-phenanthroline have been synthesized and characterized by physic-chemical and spectroscopic methods. The solid-state structures of 1 and 2 were determined by single crystal X-ray crystallography, which revealed distorted square pyramidal geometry. In solid-state structure, 1 is self-assembled via intermolecular π…π stacking and the distances between centroids of aromatic ring is 3.525 Å. L1H2 is a diprotic tridentate Schiff base ligand having ONO donor site. Infrared spectra, ligand field spectra and magnetic susceptibility measurements agree with the observed crystal structures. The EPR spectra of these complexes in frozen DMSO solutions showed a single at g ca. 2. The trend in g-value (g|| > g⊥ > 2.0023) suggests that the unpaired electron on copper (II) has d character. Copper (II) complexes 1-3 yielded an irreversible couple corresponding to the Cu (II)/Cu (I) redox process. Superoxide dismutase activity of all these complexes has been revealed to catalyze the dismutation of superoxide (O2-) and IC50 values were evaluated and discussed. Antimicrobial and antifungal activities of these complexes were also investigated.

  6. Preparation for Compensatory Forward Stepping in Parkinson’s Disease

    PubMed Central

    King, Laurie A.; St George, Rebecca J.; Carlson-Kuhta, Patricia; Nutt, John G.; Horak, Fay B.

    2010-01-01

    Objective To characterize preparation for compensatory stepping in people with Parkinson’s disease (PD) compared with healthy control subjects, and to determine whether levodopa medication improves preparation or the execution phases of the step. Design Observational study. Setting Outpatient neuroscience laboratory. Participants Nineteen participants with idiopathic PD tested both in the on and off levodopa states and 17 healthy subjects. Intervention Moveable platform with posterior translations of 24cm at 56cm/s. Main Outcome Measures Compensatory steps forward, in response to a backward surface translation (24cm amplitude at 56cm/s), were categorized according to the presence of an anticipatory postural adjustment (APA) before stepping: no APA, single APA, or multiple APAs. The following step parameters were calculated: step latency, step length, center of mass (CoM) average velocity, and CoM displacement at the step initiation. Results Lateral APAs were evident in 57% and 42% of trials for people with PD in the off and on medication states, respectively, compared with only 10% of trials for control subjects. Compared with subjects with PD who did not have APAs, those subjects with PD who did make an APA prior to stepping had significantly later (mean ± SEM, 356 ± 16ms vs 305 ± 8ms) and shorter (mean ± SEM, 251 ± 27mm vs 300 ± 16mm) steps, their CoM was significantly farther forward (185 ± 7mm vs 171 ± 5mm) at foot-off, and they took significantly more steps to regain equilibrium. Levodopa did not affect the preparation or execution phase of compensatory stepping. Poor axial scores and reports of freezing in the United Parkinson’s Disease Rating Scale were associated with use of 1 or more APAs before compensatory stepping. Conclusions Lateral postural preparation prior to compensatory stepping in subjects with PD was associated with inefficient balance recovery from external perturbations. PMID:20801249

  7. Hierarchical Controlled Remote State Preparation by Using a Four-Qubit Cluster State

    NASA Astrophysics Data System (ADS)

    Ma, Peng-Cheng; Chen, Gui-Bin; Li, Xiao-Wei; Zhan, You-Bang

    2018-06-01

    We propose a scheme for hierarchical controlled remote preparation of an arbitrary single-qubit state via a four-qubit cluster state as the quantum channel. In this scheme, a sender wishes to help three agents to remotely prepare a quantum state, respectively. The three agents are divided into two grades, that is, an agent is in the upper grade and other two agents are in the lower grade. In this process of remote state preparation, the agent of the upper grade only needs the assistance of any one of the other two agents for recovering the sender's original state, while an agent of the lower grade needs the collaboration of all the other two agents. In other words, the agents of two grades have different authorities to reconstruct sender's original state.

  8. Nano-ZnO/ZnO-HAPw prepared via sol-gel method and antibacterial activities of inorganic agents on six bacteria associated with oral infections

    NASA Astrophysics Data System (ADS)

    Jin, Jianfeng; Liu, Wenying; Zhang, Wenyun; Chen, Qinghua; Yuan, Yanbo; Yang, Lidou; Wang, Qintao

    2014-10-01

    The antibacterial activity of zinc oxide (ZnO) and the strengthening of hydroxylapatite whiskers (HAPws) have been widely studied and applied. However, the antibacterial properties of ZnO-HAPws have scarcely been researched. The aim of this study was to further investigate several types of nano-ZnO morphologies of ZnO-HAPws that were prepared using the sol-gel method at different pondus hydrogenii (pH) values and temperatures. The four morphologies of ZnO-HAPws that were investigated here were granule, triangle, short rod and disc type, and these morphologies were investigated at 70 °C at pH 6.4, 37 °C at pH 6.6, 70 °C at pH 6.6 and 70 °C at pH 6.6, respectively. Next, the antibacterial activity of ZnO-HAPw was compared to that of nano-ZnO, commercially available ZnO and tetrapod-like ZnO whiskers (T-ZnOw) with six bacteria that are associated with oral infections: Streptococcus mutans, Lactobacillus casei, Candida albicans, Actinomyces viscosus, Staphylococcus aureus and Escherichia coli. The results of examinations of the minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) showed that the antibacterial activity of ZnO-HAPw exceeded that of the commercially available ZnO and T-ZnOw. Additionally, analysis of variance (ANOVA) analysis of the MBCs revealed that the four tested antibacterial agents had significantly different effects on S. mutans ( F = 8.940; P = 0.006), S. aureus ( F = 6.924; P = 0.013) and E. coli ( F = 4.468; P = 0.04). ANOVA analyses of the MICs revealed that the four tested antibacterial agents had significantly different effects on S. mutans ( F = 6.183; P = 0.018), A. viscosus ( F = 4.531; P = 0.039) and S. aureus ( F = 18.976; P = 0.001).

  9. Morphology and crystallinity of ZnS nanocolumns prepared by glancing angle deposition.

    PubMed

    Lu, Lifang; Zhang, Fujun; Xu, Zheng; Zhao, Suling; Wang, Yongsheng

    2010-03-01

    ZnS films with different morphologies and nanometer structures were fabricated via high vacuum electron beam deposition by changing the oblique angle alpha between the incoming particle flux and the substrate normal. The morphology and crystallinity of ZnS nanocrystalline films prepared on the substrates at alpha = 0 degrees and 80 degrees were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction. These experimental results show that the ZnS nanocolumn structure was formed at the situation of alpha = 80 degrees. The incidence angle also strongly influenced the crystallinity of thin films. The most intensive diffraction peaks changed from (220) to (111) when the incidence angle was set to 0 degrees and 80 degrees. The dynamic growth process of ZnS films at alpha = 0 degrees and 80 degrees has been analyzed by shadow effect and atomic surface diffusion. The transmittance spectra of the ZnS thin films prepared at different oblique angles were measured, and the transmissivity of ZnS nanocolumn thin films was enhanced compared with ZnS thin films prepared by normal deposition in the visible light range.

  10. Development of polyimide foams with blowing agents

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Sorathia, Usman A. K. (Inventor); Lee, Raymond (Inventor)

    1985-01-01

    A method of preparing a polyimide foam which includes the steps of: preparing, foaming, and curing a precursor containing at least one alkyl ester of 3,3'4,4'-benzophenonetetracarboxylic acid; a meta- or para-substituted aromatic diamine; a heterocyclic diamine; an aliphatic diamine; and a solid blowing agent. The blowing agent is added to said precursor in a concentration which is sufficient to effect at least one of the following attributes of the foam: cell size, proportion of open cells, cell density, and indentation load deflection.

  11. Comparative Evaluation of Using NOTA and DOTA Derivatives as Bifunctional Chelating Agents in the Preparation of 68Ga-Labeled Porphyrin: Impact on Pharmacokinetics and Tumor Uptake in a Mouse Model.

    PubMed

    Guleria, Mohini; Das, Tapas; Amirdhanayagam, Jeyachitra; Sarma, Haladhar D; Dash, Ashutosh

    2018-02-01

    Both NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid) and DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) derivatives have been used as bifunctional chelating agents (BFCAs) for the preparation of 68 Ga-labeled target-specific agents having potential for positron emission tomography (PET) imaging of cancerous lesions. In the present work, the authors have attempted a comparative pharmacokinetic evaluation between 68 Ga-labeled porphyrins prepared using NOTA and DOTA derivatives as the BFCAs. A symmetrical porphyrin derivative, 5,10,15,20-tetrakis(p-carboxymethyleneoxyphenyl)porphyrin, was synthesized and coupled with two different BFCAs viz. p-NH 2 -benzyl-NOTA and p-NH 2 -benzyl-DOTA. Both the porphyrin-BFCA conjugates were radiolabeled with 68 Ga. A comparative bioevaluation involving pharmacokinetics and tumor affinity was performed in a tumor-bearing small animal model. Gallium-68-labeled porphyrin-amido-benzyl-NOTA and porphyrin-amido-benzyl-DOTA complexes were prepared with high radiochemical purity. Both radiolabeled complexes exhibited almost similar stability in human serum and near-identical tumor affinity and pharmacokinetic behavior in animal studies. The present study demonstrates that the pharmacokinetic behavior of 68 Ga-labeled porphyrin derivatives, prepared using either NOTA or DOTA derivatives as BFCAs, remains almost identical and hence both NOTA and DOTA derivatives could be considered equivalent for developing 68 Ga-based PET agents for imaging of tumorous lesions.

  12. Cell-permeable Ln(III) chelate-functionalized InP quantum dots as multimodal imaging agents.

    PubMed

    Stasiuk, Graeme J; Tamang, Sudarsan; Imbert, Daniel; Poillot, Cathy; Giardiello, Marco; Tisseyre, Céline; Barbier, Emmanuel L; Fries, Pascal Henry; de Waard, Michel; Reiss, Peter; Mazzanti, Marinella

    2011-10-25

    Quantum dots (QDs) are ideal scaffolds for the development of multimodal imaging agents, but their application in clinical diagnostics is limited by the toxicity of classical CdSe QDs. A new bimodal MRI/optical nanosized contrast agent with high gadolinium payload has been prepared through direct covalent attachment of up to 80 Gd(III) chelates on fluorescent nontoxic InP/ZnS QDs. It shows a high relaxivity of 900 mM(-1) s(-1) (13 mM(-1 )s(-1) per Gd ion) at 35 MHz (0.81 T) and 298 K, while the bright luminescence of the QDs is preserved. Eu(III) and Tb(III) chelates were also successfully grafted to the InP/ZnS QDs. The absence of energy transfer between the QD and lanthanide emitting centers results in a multicolor system. Using this convenient direct grafting strategy additional targeting ligands can be included on the QD. Here a cell-penetrating peptide has been co-grafted in a one-pot reaction to afford a cell-permeable multimodal multimeric MRI contrast agent that reports cellular localization by fluorescence and provides high relaxivity and increased tissue retention with respect to commercial contrast agents.

  13. 22 CFR 51.22 - Passport agents and passport acceptance agents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Passport agents and passport acceptance agents. 51.22 Section 51.22 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.22 Passport agents and passport acceptance agents. (a) U.S. citizen employees of the...

  14. 22 CFR 51.22 - Passport agents and passport acceptance agents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Passport agents and passport acceptance agents. 51.22 Section 51.22 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.22 Passport agents and passport acceptance agents. (a) U.S. citizen employees of the...

  15. 22 CFR 51.22 - Passport agents and passport acceptance agents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Passport agents and passport acceptance agents. 51.22 Section 51.22 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.22 Passport agents and passport acceptance agents. (a) U.S. citizen employees of the...

  16. 22 CFR 51.22 - Passport agents and passport acceptance agents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Passport agents and passport acceptance agents. 51.22 Section 51.22 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.22 Passport agents and passport acceptance agents. (a) U.S. citizen employees of the...

  17. 22 CFR 51.22 - Passport agents and passport acceptance agents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Passport agents and passport acceptance agents. 51.22 Section 51.22 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.22 Passport agents and passport acceptance agents. (a) U.S. citizen employees of the...

  18. Exploration of agent of change’s role in biodiesel energy transition process using agent-based model

    NASA Astrophysics Data System (ADS)

    Hidayatno, A.; Vicky, L. R.; Destyanto, A. R.

    2017-11-01

    As the world’s largest Crude Palm Oil (CPO) producer, Indonesia uses CPO as raw material for biodiesel. A number of policies have been designed by the Indonesian government to support adoption of biodiesel. However, the role of energy alternatives faced complex problems. Agent-based modeling can be applied to predict the impact of policies on the actors in the business process to acquire a rich discernment of the behavior and decision making by the biodiesel industries. This study evaluates government policy by attending at the adoption of the biodiesel industry in the tender run by a government with the intervention of two policy options biodiesel energy utilization by developing an agent-based model. The simulation result show that the policy of adding the biodiesel plant installed capacity has a good impact in increasing the production capacity and vendor adoption in the tender. Even so, the government should consider the cost to be incurred and the profits for vendors, so the biodiesel production targets can be successfully fulfilled.

  19. Waste Material of Propolis as a Film Forming Agent Intended to Modify the Metronidazole Release: Preparation and Characterization.

    PubMed

    de Toledo, Lucas de Alcântara Sica; Rosseto, Hélen Cássia; Ravani, Laura; Cortesi, Rita; Bruschi, Marcos Luciano

    2016-01-01

    Metronidazole is an antimicrobial agent utilized for the treatment of protozoa and anaerobic bacteria infections. Many times, it is necessary to modify the metronidazole release, and the development of modified release systems may be suggested. In this study, we are able to investigate the use of the residue normally thrown out from the preparation of propolis extracts (BP) as strategy to modify the metronidazole release. We prepared films containing polymeric adjuvant (gelatin or ethylcellulose) and metronidazole, by solvent casting method. Density, mechanical properties, water vapor permeability (WVP), moisture uptake capacity (MUC), thermogravimetry, differential scanning calorimetry, Fourier transform infrared spectroscopy (FT-IR), and in vitro metronidazole release were investigated. Thickness and density of the preparations indicated that the compounds were homogeneously dispersed throughout. Mechanical properties were influenced by film composition. Films containing gelatin showed higher resistance to stress while those containing ethylcellulose presented greater flexibility. The greater the adjuvant concentrations lower the resistance to rupture and the elasticity, but higher MUC and WVP of formulations. FT-IR tests suggested interactions between BP and the adjuvants. Films were capable to protect the metronidazole and changed its release profile. BP films are of great practical importance constituting a novel strategy to modify the metronidazole release.

  20. Studies on the preparation of Caro’s acid by ultrasonic enhanced electrochemistry

    NASA Astrophysics Data System (ADS)

    Li, Linbo; Yu, Zeli; Hong, Tao; Fang, Zhao; Peng, Jishi; Yang, Zhao

    2017-06-01

    Ultrasonic cavitation effects can generate hydroxyl radicals and high energy, which is widely applied in the field of oxidation currently. Ultrasound-enhanced electrochemical is used to prepare Caro’s acid, which improves the generate rate of Caro’s acid. In this article, the influences of ultrasonic frequency and ultrasonic power on the electrolysis voltage, electrolyte temperature, electrolyte concentration and the concentration of additive in the process of electrochemical preparation of Caro’s acid was studied. And the optimal production conditions were determined. The research results showed that ultrasonic can significantly improve the production of Caro’s acid and the product can increase by about 20 g/L under the best condition.

  1. [Comparative protein analytic studies of various intravenous 7S-immunoglobulin preparations].

    PubMed

    Fateh-Moghadam, A; Wick, M; Simon, H

    1984-02-01

    Seven different commercial intravenous 7S-immunoglobulin preparations have been examined by electrophoresis, immunoelectrophoresis, quantitative determination of immunoglobulins and other proteins, gel chromatography and analytical ultracentrifugation. No significant difference concerning IgG and monomeric immunoglobulin concentrations was observed. The content of IgM, dimers and polymers showed slight, that of IgA considerable differences. All immunoglobulin preparations comply with the European Pharmacopoea requirements. The rate of adverse reactions should be equally low due to similar dimer and polymer contents. IgA-free preparations are considered to be more suitable in primary hypogammaglobulinaemia whereas IgA-containing preparations could be of benefit in acquired hypogammaglobulinaemia. While the presence of an intact immunoglobulin molecule is thought to be essential for its full therapeutic efficacy, the influence of the preparation method is still in debate.

  2. Hydrolysis and photolysis of oxytetracycline in aqueous solution

    USDA-ARS?s Scientific Manuscript database

    Oxytetracycline ((2Z,4S,4aR,5S,5aR,6S,12aS)-2-(amino-hydroxy-methylidene)-4-dimethylamino-5,6,10,11,12a-pentahydroxy-6-methyl-4,4a,5,5a-tetrahydrotetracene-1,3,12-trione) is a member of tetracycline antibiotics family and is widely administered to farm animals for the purpose of therapeutical treatm...

  3. Morphological study of polymethyl methacrylate microcapsules filled with self-healing agents

    NASA Astrophysics Data System (ADS)

    Ahangaran, Fatemeh; Hayaty, Mehran; Navarchian, Amir H.

    2017-03-01

    Polymethyl methacrylate (PMMA) microcapsules filled with epoxy prepolymer, 3-aminomethyl-3,5,5-trimethylcyclohexylamine, and pentaerythritol tetrakis (3-mercaptopropionate) as healing agents have been prepared separately through internal phase separation method for self-healing purposes. PMMA with two different molecular weights (M bar1 = 36,000 g/mol and M bar2 = 550,000 g/mol) were used with two types of different emulsifiers (ionic and polymeric) to prepare microcapsules. The morphology of healing agent microcapsules was investigated using field emission scanning electron microscopy (FESEM). It was found that PMMA microcapsules separately filled with epoxy and amine had core-shell morphologies with smooth surfaces. The mercaptan/PMMA particles exhibited core-shell and acorn-shape morphologies. The surface morphology of mercaptan microcapsules changed from holed to plain in different emulsion systems. The spreading coefficient (S) of phases in the prepared emulsion systems were calculated from interfacial tension (σ) and contact angle (θ) measurements. The theoretical equilibrium morphology of PMMA microcapsules was predicted according to spreading coefficient values of phases in emulsion systems. It was also found that the surface morphology of PMMA microcapsules depended strongly on the nature of the core, molecular weight of PMMA, type and concentration of emulsifier.

  4. 75 FR 6397 - AMC USA, Inc. v. International First Service S.A. a/k/a IFS S.A, its Agents, Affiliated, Related...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-09

    .../k/a IFS S.A, its Agents, Affiliated, Related and Partner Companies, and International First Service Argentina a/k/a AR-IFS, its Agents, Affiliated, Related and Partner Companies, and International First Service USA, Inc. a/k/a IFS USA, Inc. d/b/a Global Wine Logistics USA Inc. a/k/a GWL USA, Inc., and Global...

  5. Bionic multisilicon copolymers used as novel cross-linking agents for preparing anion exchange hybrid membranes.

    PubMed

    Wu, Yonghui; Luo, Jingyi; Wu, Cuiming; Xu, Tongwen; Fu, Yanxun

    2011-05-26

    Bionic multisilicon copolymers have long-main chains and many branched chains, and contain multifunctional groups of -N(+)(CH(3))(3)Cl(-) and -Si(OCH(3))(3), which are similar to the stem, branch, fruit, and acetabula of a vine from bionic aspect, respectively. They have high flexibility, charge density, and cross-linking ability and thus can be used as novel cross-linking agents for preparing anion-exchange hybrid membranes. High content of -Si(OCH(3))(3) groups (68-78%) is suitable to enhance membrane stabilities. The membranes are stable in 65 °C water up to 120 h and can keep integrity in 2 mol/L NaOH for 192 h. High content of -N(+)(CH(3))(3)Cl(-) groups (42-55%) is suitable to enhance membrane electrical properties. The membranes have low membrane resistance (R(m), 0.59-0.94 Ω cm(2)) and high diffusion dialysis performance. The acid (H(+)) dialysis coefficients (U(H)) are in the range of 0.007-0.075 m h(-1) at room temperature and 0.015-0.115 m h(-1) at 40 °C. The separation factor (S(H/Fe)) can reach up to 43 at room temerature and 49 at 40 °C. All of the membranes are highly homogeneous, mechanically stable (21-31 MPa, 25-147%), and thermally stable (227-275 °C for halide form membranes, and 157-172 °C for OH(-) form membranes). Hence, the investigation of multisilicon copolymers will give rise to a new developing field in material and membrane sciences.

  6. 77 FR 8753 - Furnishing Identifying Number of Tax Return Preparer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... return preparer must be an attorney, certified public accountant, enrolled agent, or registered tax... ``decided to allow certain individuals who are not attorneys, certified public accountants, enrolled agents... may obtain a PTIN: (1) Tax return preparers supervised by attorneys, certified public accountants...

  7. 21 CFR 516.22 - Permanent-resident U.S. agent for foreign sponsor.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS NEW ANIMAL DRUGS FOR MINOR USE AND MINOR SPECIES Designation of a Minor Use or Minor Species New Animal Drug § 516.22 Permanent-resident U.S. agent..., decisions, requirements, and other communications may be made on behalf of the sponsor. Notifications of...

  8. 21 CFR 516.22 - Permanent-resident U.S. agent for foreign sponsor.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS NEW ANIMAL DRUGS FOR MINOR USE AND MINOR SPECIES Designation of a Minor Use or Minor Species New Animal Drug § 516.22 Permanent-resident U.S. agent..., decisions, requirements, and other communications may be made on behalf of the sponsor. Notifications of...

  9. Preparation and Cyclodextrin Solubilization of the Antibacterial Agent Benzoyl Metronidazole

    PubMed Central

    Yang, Shuo

    2013-01-01

    A one-pot method for the preparation of benzoyl metronidazole was achieved by using N,N′-carbonyldiimidazole as a coupling reagent. Moreover, it was found that the byproduct imidazole as the catalyst promoted the reaction. In addition, the β-cyclodextrin solubilization of benzoyl metronidazole was investigated by phase-solubility method. The phase-solubility studies indicated that the solubility of benzoyl metronidazole (S = 0.1435 g/L) was substantially increased 9.7-fold (S′ = 1.3881 g/L) by formation of 1 : 1 benzoyl metronidazole/β-cyclodextrin complexes in water, and the association constant K a value was determined to be 251 (±23) dm3/mol. Therefore, β-cyclodextrin can work as a pharmaceutical solubilizer for benzoyl metronidazole and may improve its oral bioavailability. PMID:23970831

  10. Surface Structure Spread Single Crystals (S4C): Preparation and characterization

    NASA Astrophysics Data System (ADS)

    de Alwis, A.; Holsclaw, B.; Pushkarev, V. V.; Reinicker, A.; Lawton, T. J.; Blecher, M. E.; Sykes, E. C. H.; Gellman, A. J.

    2013-02-01

    A set of six spherically curved Cu single crystals referred to as Surface Structure Spread Single Crystals (S4Cs) has been prepared in such a way that their exposed surfaces collectively span all possible crystallographic surface orientations that can be cleaved from the face centered cubic Cu lattice. The method for preparing these S4Cs and for finding the high symmetry pole point is described. Optical profilometry has been used to determine the true shapes of the S4Cs and show that over the majority of the surface, the shape is extremely close to that of a perfect sphere. The local orientations of the surfaces lie within ± 1° of the orientation expected on the basis of the spherical shape; their orientation is as good as that of many commercially prepared single crystals. STM imaging has been used to characterize the atomic level structure of the Cu(111) ± 11°-S4C. This has shown that the average step densities and the average step orientations match those expected based on the spherical shape. In other words, although there is some distribution of step-step spacing and step orientations, there is no evidence of large scale reconstruction or faceting. The Cu S4Cs have local structures based on the ideal termination of the face centered cubic Cu lattice in the direction of termination. The set of Cu S4Cs will serve as the basis for high throughput investigations of structure sensitive surface chemistry on Cu.

  11. 75 FR 60316 - User Fees Relating to Enrollment and Preparer Tax Identification Numbers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-30

    ... a PTIN, a tax return preparer must be an attorney, certified public accountant, enrolled agent, or... that tax return preparers who are attorneys, certified public accountants, or enrolled agents already... who are not otherwise licensed as an attorney, certified public accountant, or enrolled agent...

  12. An experimental study on the preparation of tochilinite-originated intercalation compounds comprised of Fe 1-xS host layers and various kinds of guest layers

    NASA Astrophysics Data System (ADS)

    Peng, Yiya; Xi, Guangcheng; Zhong, Chang; Wang, Linping; Lu, Jun; Sun, Ximeng; Zhu, Lu; Han, Qikun; Chen, Lin; Shi, Lei; Sun, Mei; Li, Qianrong; Yu, Min; Yin, Mingwen

    2009-08-01

    Tochilinite represents a mineral group of ordered mixed-layer structures containing alternating Fe 1-xS layers with mackinawite-like structure and metal hydroxide layers with Mg(OH) 2-like structure. In this article, we report the preparation of a series of tochilinite-originated (or Fe 1-xS-based) intercalation compounds (ICs). According to their preparation procedures, these ICs can be divided into four kinds. The first kind of IC was sodium tochilinite (Na-tochilinite), which was prepared by the hydrothermal reaction of metallic Fe particles with concentrated Na 2S·9H 2O aqueous solutions. The hydroxide layer of the Na-tochilinite was a mixed hydroxide of Na + ions along with a certain amount of Fe 2+ ions. When the hydroxide layer of the Na-tochilinite completely dissolved in aqueous solutions, a Fe-deficient mackinawite-like phase Fe 1-xS was obtained, which was probably an electron-deficient p-type conductor. The second kind of ICs was prepared by 'low-temperature direct intercalation in aqueous solutions, using Na-tochilinite as a parental precursor. When the Na-tochilinite was ultrasonicated in aqueous solutions containing Lewis basic complexing agents (like NH 3, N 2H 4, 2,2'-bipyridine (bipy), and 1,10-phenanthroline (phen)), the Na + ions of the Na-tochilinite were removed and the Lewis basic complexing agents entered the hydroxide layer of the Na-tochilinite and became coordinated with the Fe 2+ ions, and the second kind of ICs was thus produced. The second kind of ICs includes NH 3 IC, N 2H 4 IC, N 2H 4-NH 3 IC, [Fe(bipy) 3] 2+-containing IC and [Fe(phen) 3] 2+-containing IC. The third kind of ICs, which includes NH 3 IC, N 2H 4-NH 3 IC and N 2H 4-LiOH (NaOH) IC, was prepared by the hydrothermal reaction of metallic Fe particles with (NH 4) 2S aqueous solution, S (elemental) + N 2H 4·H 2O aqueous solution, and S + N 2H 4·H 2O + LiOH (NaOH) aqueous solution, respectively. The third kind of ICs has a close relationship with the second kind of ICs both

  13. Preparation and characterization of graphene/CdS nanocomposites

    NASA Astrophysics Data System (ADS)

    Wu, Jili; Bai, Song; Shen, Xiaoping; Jiang, Lei

    2010-11-01

    Graphene-based nanocomposites are emerging as a new class of materials that hold promise for many applications. In this paper, we present a facile approach for the preparation of graphene/CdS nanocomposites through simple reflux processes, in which thiourea (CS(NH 2) 2) and thioacetamide (C 2H 5NS) act as a sulphide source, respectively. The samples were characterized by the X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectrum (FT-IR), ultraviolet-visible (UV-vis) spectroscopy and thermogravimetry analysis. It was shown that in the nanocomposites, the CdS nanoparticles were densely and uniformly deposited on the graphene sheets, and the sulphide source used has a great influence on the morphology, structure and property of the graphene/CdS nanocomposites. The good distribution of CdS nanoparticles on graphene sheets guarantees the efficient optoelectronic properties of graphene/CdS and would be promising for practical applications in future nanotechnology.

  14. Sensitive and Rapid Identification of Biological Threat Agents

    DTIC Science & Technology

    1999-12-01

    plague, and Bruceila abortis , the etiologic agent of brucellosis, indicate that the Qiagen procedures will also be effective in preparing these agents for...procedure for two bacteria, Yersinia pestis and Bruceila abortis , and found that DNA isolated with this method yielded PCR detection limits at least

  15. Current Status and Prospects for Cannabidiol Preparations as New Therapeutic Agents.

    PubMed

    Fasinu, Pius S; Phillips, Sarah; ElSohly, Mahmoud A; Walker, Larry A

    2016-07-01

    States and the federal government are under growing pressure to legalize the use of cannabis products for medical purposes in the United States. Sixteen states have legalized (or decriminalized possession of) products high in cannabidiol (CBD) and with restricted ∆(9) -tetrahydrocannabinol (∆(9) -THC) content. In most of these states, the intent is for use in refractory epileptic seizures in children, but in a few states, the indications are broader. This review provides an overview of the pharmacology and toxicology of CBD; summarizes some of the regulatory, safety, and cultural issues relevant to the further exploitation of its antiepileptic or other pharmacologic activities; and assesses the current status and prospects for clinical development of CBD and CBD-rich preparations for medical use in the United States. Unlike Δ(9) -THC, CBD elicits its pharmacologic effects without exerting any significant intrinsic activity on the cannabinoid receptors, whose activation results in the psychotropic effects characteristic of Δ(9) -THC, and CBD possesses several pharmacologic activities that give it a high potential for therapeutic use. CBD exhibits neuroprotective, antiepileptic, anxiolytic, antipsychotic, and antiinflammatory properties. In combination with Δ(9) -THC, CBD has received regulatory approvals in several European countries and is currently under study in trials registered by the U.S. Food and Drug Administration in the United States. A number of states have passed legislation to allow for the use of CBD-rich, limited Δ(9) -THC-content preparations of cannabis for certain pathologic conditions. CBD is currently being studied in several clinical trials and is at different stages of clinical development for various medical indications. Judging from clinical findings reported so far, CBD and CBD-enriched preparations have great potential utility, but uncertainties regarding sourcing, long-term safety, abuse potential, and regulatory dilemmas remain.

  16. Child Soldiers: Are U.S. Military Members Prepared to Deal with the Threat?

    DTIC Science & Technology

    2006-02-15

    killing child soldiers. Additional attention should also be invested into identifying interventions that would decrease the negative stigma of mental...AIR WAR COLLEGE AIR UNIVERSITY CHILD SOLDIERS: ARE U.S. MILITARY MEMBERS PREPARED TO DEAL WITH THE THREAT? by Judith Hughes, LtCol, USAF A...COVERED 00-00-2006 to 00-00-2006 4. TITLE AND SUBTITLE Child Soldiers: Are U.S. Military Members Prepared to Deal with the Threat? 5a. CONTRACT

  17. Deals Among Rational Agents,

    DTIC Science & Technology

    1985-03-01

    ARD-AI57 966 DEALS AMONG RATIONAL AGENTS(U) STANFORD UNIV CA DEPT OF 1/1lit COMPUTER SCIENCE J S ROSENSCHEIN ET AL. MAR 857 STAN-CS-85-1e42 NOO039-83... Rational Agents by Jeffrey S. Rosenschemn Michael R. Genesereth Contract N00039-83-c-0136 Department of Computer Science Stanford University Stanford, CA... Rational Agents Jeffrey S. Rosenschein Michael R. Genesereth COMPUTER SCIENCE DEPARTME NT Stanford University Sta-;!ord, California 94305 A ~ ,2 TA

  18. Preparation and investigation of Ge-S-I glasses for infrared fiber optics

    NASA Astrophysics Data System (ADS)

    Velmuzhov, A. P.; Sukhanov, M. V.; Plekhovich, A. D.; Snopatin, G. E.; Churbanov, M. F.; Iskhakova, L. D.; Ermakov, R. P.; Kotereva, T. V.; Shiryaev, V. S.

    2016-02-01

    Glass samples of [GeSx]90I10 (x = 1.5, 1.7, 2.0, 2.3, 2.45, 2.6) compositions were prepared, and some their thermal, optical properties as well as tendency to crystallization were investigated. The compositional dependences of glass transition temperature, volume fraction of crystallized phase and activation energy of glass formation (Eg) have nonmonotonic character with a maximum for [GeS2.0]90I10 glass. Glasses of 85.8GeS2-14.2GeI4 and [GeS1.5]90I10 compositions are identified as promising for preparation of optical fiber. For the first time, Ge-S-I glass fibers were produced. Minimum optical losses in 85.8GeS2-14.2GeI4 glass fiber were 2.7 dB/m at a wavelength of 5.1 μm, and that in [GeS1.5]90I10 glass fiber were 14.5 dB/m at 5.5 μm.

  19. Preparation and bactericide activity of gallic acid stabilized gold nanoparticles

    NASA Astrophysics Data System (ADS)

    Moreno-Álvarez, S. A.; Martínez-Castañón, G. A.; Niño-Martínez, N.; Reyes-Macías, J. F.; Patiño-Marín, N.; Loyola-Rodríguez, J. P.; Ruiz, Facundo

    2010-10-01

    In this work, gold nanoparticles with three different sizes (13.7, 39.4, and 76.7 nm) were prepared using a simple aqueous method with gallic acid as the reducing and stabilizing agent, the different sizes were obtained varying some experimental parameters as the pH of the reaction and the amount of the gallic acid. The prepared nanoparticles were characterized using X-ray diffraction, transmission electron microscopy, dynamic light scattering, and UV-Vis spectroscopy. Samples were identified as elemental gold and present spherical morphology, a narrow size distribution and good stabilization according to TEM and DLS results. The antibacterial activity of this gallic acid stabilized gold nanoparticles against S. mutans (the etiologic agent of dental caries) was assessed using a microdilution method obtaining a minimum inhibitory concentration of 12.31, 12.31, and 49.25 μg/mL for 13.7, 39.4, and 76.7 nm gold nanoparticles, respectively. The antibacterial assay showed that gold nanoparticles prepared in this work present a bactericide activity by a synergistic action with gallic acid. The MIC found for this nanoparticles are much lower than those reported for mixtures of gold nanoparticles and antibiotics.

  20. Preparation and characterization of ZnS thin films by the chemical bath deposition method (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Ando, Shizutoshi; Iwashita, Taisuke

    2017-06-01

    Nowadays, the conversion efficiency of Cu(In・Ga)Se2 (CIGS)-based solar cell already reached over 20%. CdS thin films prepared by chemical bath deposition (CBD) method are used for CIGS-based thin film solar cells as the buffer layer. Over the past several years, a considerable number of studies have been conducted on ZnS buffer layer prepared by CBD in order to improve in conversion efficiency of CIGS-based solar cells. In addition, application to CIGS-based solar cell of ZnS buffer layer is expected as an eco-friendly solar cell by cadmium-free. However, it was found that ZnS thin films prepared by CBD included ZnO or Zn(OH)2 as different phase [1]. Nakata et. al reported that the conversion efficiency of CIGS-based solar cell using ZnS buffer layer (CBD-ZnS/CIGS) reached over 18% [2]. The problem which we have to consider next is improvement in crystallinity of ZnS thin films prepared by CBD. In this work, we prepared ZnS thin films on quarts (Si02) and SnO2/glass substrates by CBD with the self-catalysis growth process in order to improve crystallinity and quality of CBD-ZnS thin films. The solution to use for CBD were prepared by mixture of 0.2M ZnI2 or ZnSO4, 0.6M (NH2)2CS and 8.0M NH3 aq. In the first, we prepared the particles of ZnS on Si02 or SnO2/glass substrates by CBD at 80° for 20 min as initial nucleus (1st step ). After that, the particles of ZnS on Si02 or SnO2/glass substrates grew up to be ZnS thin films by CBD method at 80° for 40 min again (2nd step). We found that the surface of ZnS thin films by CBD with the self-catalyst growth process was flat and smooth. Consequently, we concluded that the CBD technique with self-catalyst growth process in order to prepare the particles of ZnS as initial nucleus layer was useful for improvement of crystallinity of ZnS thin films on SnO2/glass. [1] J.Vidal et,al., Thin Solid Films 419 (2002) 118. [2] T.Nakata et.al., Jpn. J. Appl. Phys. 41(2B), L165-L167 (2002)

  1. Capping agents in nanoparticle synthesis: Surfactant and solvent system

    NASA Astrophysics Data System (ADS)

    Gulati, Shivani; Sachdeva, M.; Bhasin, K. K.

    2018-05-01

    The preparation of nanomaterials by organometallic precursors require a capping agent, which primarily acts as stabilizing agent and provide colloidal stability along with preventing agglomeration and stopping uncontrolled growth. Final morphology of nanocrystal largely depends on the type of capping agent which is adsorbed on the surface of nanocrystal. Thus capping agents are the keys to obtain the small-sized nanoparticles and are very frequently used in colloidal synthesis of nanoparticles to avoid its overgrowth.

  2. Natural chelating agents for radionuclide decorporation

    DOEpatents

    Premuzic, E.T.

    1985-06-11

    This invention relates to the production of metal-binding compounds useful for the therapy of heavy metal poisoning, for biological mining and for decorporation of radionuclides. The present invention deals with an orderly and effective method of producing new therapeutically effective chelating agents. This method uses challenge biosynthesis for the production of chelating agents that are specific for a particular metal. In this approach, the desired chelating agents are prepared from microorganisms challenged by the metal that the chelating agent is designed to detoxify. This challenge induces the formation of specific or highly selective chelating agents. The present invention involves the use of the challenge biosynthetic method to produce new complexing/chelating agents that are therapeutically useful to detoxify uranium, plutonium, thorium and other toxic metals. The Pseudomonas aeruginosa family of organisms is the referred family of microorganisms to be used in the present invention to produce the new chelating agent because this family is known to elaborate strains resistant to toxic metals.

  3. The Effects of Die Relief Agent on the Retention of Full Coverage Castings,

    DTIC Science & Technology

    1981-02-19

    autopolymerizing resin. A diamond rotary instrument and a high speed dental handpiece using air- water coolant were employed to prepare the crown of each tooth...777 109 502 ARMY INST OF DENTAL RESEARCH WASHINGTON DC F/6 6/5 THE EFFECTS OF DIE RELIEF AGENT ON THE RETENTION OF FULL COYERA--ETC(U) FES 81 S 6...Kuffler" 4W Eugene F.Huget, COL, (Ret.) .9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT, TASK U.S. Army Institute of Dental

  4. Using an agent-based model to simulate children’s active travel to school

    PubMed Central

    2013-01-01

    Background Despite the multiple advantages of active travel to school, only a small percentage of US children and adolescents walk or bicycle to school. Intervention studies are in a relatively early stage and evidence of their effectiveness over long periods is limited. The purpose of this study was to illustrate the utility of agent-based models in exploring how various policies may influence children’s active travel to school. Methods An agent-based model was developed to simulate children’s school travel behavior within a hypothetical city. The model was used to explore the plausible implications of policies targeting two established barriers to active school travel: long distance to school and traffic safety. The percent of children who walk to school was compared for various scenarios. Results To maximize the percent of children who walk to school the school locations should be evenly distributed over space and children should be assigned to the closest school. In the case of interventions to improve traffic safety, targeting a smaller area around the school with greater intensity may be more effective than targeting a larger area with less intensity. Conclusions Despite the challenges they present, agent based models are a useful complement to other analytical strategies in studying the plausible impact of various policies on active travel to school. PMID:23705953

  5. Biothreat agents and pathology laboratories.

    PubMed

    Nelson, Ann; Wilson, Michael L

    2007-11-01

    Pathologists and laboratory staff are likely to be among the first health care workers to be aware that a potential bioterrorism attack has occurred. To prepare for such an event, it is necessary to be familiar with 1) the characteristics of bioterrorism attacks versus natural disease outbreaks, 2) which pathogens are potential bioterrorism agents; 3) the types of lesions that each causes; 4) the microbiological characteristics of each agent; 5) the Laboratory Response Network and reporting requirements, and 6) what resources are available.

  6. Combination could be another tool for bowel preparation?

    PubMed Central

    Soh, Jae Seung; Kim, Kyung-Jo

    2016-01-01

    Optimal bowel preparation increases the cecal intubation rate and detection of neoplastic lesions while decreasing the procedural time and procedural-related complications. Although high-volume polyethylene glycol (PEG) solution is the most frequently used preparation for bowel cleansing, patients are often unwilling to take PEG solution due to its large volume, poor palatability, and high incidence of adverse events, such as abdominal bloating and nausea. Other purgatives include osmotic agents (e.g., sodium phosphate, magnesium citrate, and sodium sulfate), stimulant agents (e.g., senna, bisacodyl, and sodium picosulfate), and prokinetic agents (e.g., cisapride, mosapride, and itopride). A combination of PEG with an osmotic, stimulant, or prokinetic agent could effectively reduce the PEG solution volume and increase patients’ adherence. Some such solutions have been found in several published studies to not be inferior to PEG alone in terms of bowel cleansing quality. Although combination methods showed similar efficacy and safety, the value of these studies is limited by shortcomings in study design. New effective and well-tolerated combination preparations are required, in addition to rigorous new validated studies. PMID:26973388

  7. Epoxy foams using multiple resins and curing agents

    DOEpatents

    Russick, Edward M.; Rand, Peter B.

    2000-01-01

    An epoxy foam comprising a plurality of resins, a plurality of curing agents, at least one blowing agent, at least one surfactant and optionally at least one filler and the process for making. Preferred is an epoxy foam comprising two resins of different reactivities, two curing agents, a blowing agent, a surfactant, and a filler. According to the present invention, an epoxy foam is prepared with tailorable reactivity, exotherm, and pore size by a process of admixing a plurality of resins with a plurality of curing agents, a surfactant and blowing agent, whereby a foamable mixture is formed and heating said foamable mixture at a temperature greater than the boiling temperature of the blowing agent whereby said mixture is foamed and cured.

  8. Formulation and method for preparing gels comprising hydrous aluminum oxide

    DOEpatents

    Collins, Jack L.

    2014-06-17

    Formulations useful for preparing hydrous aluminum oxide gels contain a metal salt including aluminum, an organic base, and a complexing agent. Methods for preparing gels containing hydrous aluminum oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including aluminum, an organic base, and a complexing agent.

  9. Formulation and method for preparing gels comprising hydrous cerium oxide

    DOEpatents

    Collins, Jack L; Chi, Anthony

    2013-05-07

    Formulations useful for preparing hydrous cerium oxide gels contain a metal salt including cerium, an organic base, and a complexing agent. Methods for preparing gels containing hydrous cerium oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including cerium, an organic base, and a complexing agent.

  10. Multi-stimuli responsive Cu2S nanocrystals as trimodal imaging and synergistic chemo-photothermal therapy agents

    NASA Astrophysics Data System (ADS)

    Poulose, Aby Cheruvathoor; Veeranarayanan, Srivani; Mohamed, M. Sheikh; Nagaoka, Yutaka; Romero Aburto, Rebeca; Mitcham, Trevor; Ajayan, Pulickel M.; Bouchard, Richard R.; Sakamoto, Yasushi; Yoshida, Yasuhiko; Maekawa, Toru; Sakthi Kumar, D.

    2015-04-01

    A size and shape tuned, multifunctional metal chalcogenide, Cu2S-based nanotheranostic agent is developed for trimodal imaging and multimodal therapeutics against brain cancer cells. This theranostic agent was highly efficient in optical, photoacoustic and X-ray contrast imaging systems. The folate targeted NIR-responsive photothermal ablation in synergism with the chemotherapeutic action of doxorubicin proved to be a rapid precision guided cancer-killing module. The multi-stimuli, i.e., pH-, thermo- and photo-responsive drug release behavior of the nanoconjugates opens up a wider corridor for on-demand triggered drug administration. The simple synthesis protocol, combined with the multitudes of interesting features packed into a single nanoformulation, clearly demonstrates the competing role of this Cu2S nanosystem in future cancer treatment strategies.A size and shape tuned, multifunctional metal chalcogenide, Cu2S-based nanotheranostic agent is developed for trimodal imaging and multimodal therapeutics against brain cancer cells. This theranostic agent was highly efficient in optical, photoacoustic and X-ray contrast imaging systems. The folate targeted NIR-responsive photothermal ablation in synergism with the chemotherapeutic action of doxorubicin proved to be a rapid precision guided cancer-killing module. The multi-stimuli, i.e., pH-, thermo- and photo-responsive drug release behavior of the nanoconjugates opens up a wider corridor for on-demand triggered drug administration. The simple synthesis protocol, combined with the multitudes of interesting features packed into a single nanoformulation, clearly demonstrates the competing role of this Cu2S nanosystem in future cancer treatment strategies. Electronic supplementary information (ESI) available: Methodology and additional experimental results. See DOI: 10.1039/c4nr07139e

  11. Prepared Food Availability in U.S. Food Stores: A National Study.

    PubMed

    Zenk, Shannon N; Powell, Lisa M; Isgor, Zeynep; Rimkus, Leah; Barker, Dianne C; Chaloupka, Frank J

    2015-10-01

    Prepared, ready-to-eat foods comprise a significant part of Americans' diets and are increasingly obtained from food stores. Yet, little is known about the availability and healthfulness of prepared, ready-to-eat food offerings at stores. This study examines associations among community characteristics (racial/ethnic composition, poverty level, urbanicity) and availability of both healthier and less-healthy prepared foods in U.S. supermarkets, grocery stores, and convenience stores. Observational data were collected from 4,361 stores in 317 communities spanning 42 states in 2011 and 2012. Prepared food availability was assessed via one healthier food (salads or salad bar), three less-healthy items (pizza, hot dog/hamburger, taco/burrito/taquito), and one cold sandwich item. In 2014, multivariable generalized linear models were used to test associations with community characteristics. Overall, 63.6% of stores sold prepared foods, with 20.0% offering prepared salads and 36.4% offering at least one less-healthy item. Rural stores were 26% less likely to carry prepared salads (prevalence ratio [PR]=0.74, 95% CI=0.62, 0.88) and 14% more likely to carry at least one less-healthy prepared food item (PR=1.14, 95% CI=1.00, 1.30). Convenience stores in high-poverty communities were less likely to carry prepared salads than those in low-poverty communities (PR=0.64, 95% CI=0.47, 0.87). Among supermarkets, prepared salads were more likely to be carried in majority-white, low-poverty communities than in non-white, high-poverty communities. Increasing the healthfulness of prepared foods within stores may offer an important opportunity to improve the food environment. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  12. [Continuous observation of canal aberrations in S-shaped simulated root canal prepared by hand-used ProTaper files].

    PubMed

    Xia, Ling-yun; Leng, Wei-dong; Mao, Min; Yang, Guo-biao; Xiang, Yong-gang; Chen, Xin-mei

    2009-08-01

    To observe the formation of canal aberrations in S-shaped root canals prepared by every file of hand-used ProTaper. Fifteen S-shaped simulated resin root canals were selected. Each root canal was prepared by every file of hand-used ProTaper following the manufacturer instruction. The images of canals prepared by S1, S2, F1, F2 and F3 were taken and stored, which were divided into group S1, S2, F1, F2 and F3. One image of canal unprepared was superposed with the images of the same root canal in these five groups respectively to observe the types and number of canal aberrations, which included unprepared area, danger zone, ledge, elbow, zip and perforation. SPSS12.0 software pakage was used for Fisher's exact probabilities in 2x2 table. Unprepared area decreased following preparation by every file of ProTaper, but it still existed when the canal preparation was finished. The incidence of danger zone, elbow and zip in group F1 was 15/15, 11/15, 4/15, respectively, which was significantly higher than that in group S2(2/15,0,0) (P<0.001). Ledge appeared after prepared by F2, and increased sharply in group F3. None perforation was found in all groups. The incidence of canal aberrations begins to increase after prepared by finishing files of ProTaper.The presence of unprepared area suggests that it is essential to rinse canal abundantly during complicated canal preparation and canal antisepsis after preparation.

  13. Evaluation of real-time data obtained from gravimetric preparation of antineoplastic agents shows medication errors with possible critical therapeutic impact: Results of a large-scale, multicentre, multinational, retrospective study.

    PubMed

    Terkola, R; Czejka, M; Bérubé, J

    2017-08-01

    Medication errors are a significant cause of morbidity and mortality especially with antineoplastic drugs, owing to their narrow therapeutic index. Gravimetric workflow software systems have the potential to reduce volumetric errors during intravenous antineoplastic drug preparation which may occur when verification is reliant on visual inspection. Our aim was to detect medication errors with possible critical therapeutic impact as determined by the rate of prevented medication errors in chemotherapy compounding after implementation of gravimetric measurement. A large-scale, retrospective analysis of data was carried out, related to medication errors identified during preparation of antineoplastic drugs in 10 pharmacy services ("centres") in five European countries following the introduction of an intravenous workflow software gravimetric system. Errors were defined as errors in dose volumes outside tolerance levels, identified during weighing stages of preparation of chemotherapy solutions which would not otherwise have been detected by conventional visual inspection. The gravimetric system detected that 7.89% of the 759 060 doses of antineoplastic drugs prepared at participating centres between July 2011 and October 2015 had error levels outside the accepted tolerance range set by individual centres, and prevented these doses from reaching patients. The proportion of antineoplastic preparations with deviations >10% ranged from 0.49% to 5.04% across sites, with a mean of 2.25%. The proportion of preparations with deviations >20% ranged from 0.21% to 1.27% across sites, with a mean of 0.71%. There was considerable variation in error levels for different antineoplastic agents. Introduction of a gravimetric preparation system for antineoplastic agents detected and prevented dosing errors which would not have been recognized with traditional methods and could have resulted in toxicity or suboptimal therapeutic outcomes for patients undergoing anticancer treatment.

  14. Technical considerations in the preparation and dispensing of chemotherapy.

    PubMed

    Peters, B G

    1995-01-01

    The safe handling of cytotoxic agents is intimately related to the technical aspects of drug preparation, dispensing, and administration. The appropriate equipment, supplies, protective clothing, and waste disposal systems must be available to the health care worker who is called upon to prepare cytotoxic agents. In addition, the health care worker must be adequately trained in and familiar with the safe use of these products and equipment and the preparation techniques or manipulations necessary during cytotoxic drug compounding. The article describes in detail and reviews the technical considerations, such as aseptic technique, proper use of the biological safety cabinet, gowning and gloving, labeling, and waste disposal, that are essential to the safe preparation and dispensing of chemotherapy.

  15. Dialogic Praxis in Teacher Preparation: A Discourse Analysis of Mentoring Talk

    ERIC Educational Resources Information Center

    Bieler, Deborah

    2010-01-01

    This study examined the complexities of mentoring discourse and agentive teacher preparation. I argue that such an examination is necessary to better prepare student teachers to engage agentively with the powerful status quo in schools. I begin by discussing the intersections of current thinking about mentoring and dialogue, and I describe how…

  16. Formulation and method for preparing gels comprising hydrous hafnium oxide

    DOEpatents

    Collins, Jack L; Hunt, Rodney D; Montgomery, Frederick C

    2013-08-06

    Formulations useful for preparing hydrous hafnium oxide gels contain a metal salt including hafnium, an acid, an organic base, and a complexing agent. Methods for preparing gels containing hydrous hafnium oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including hafnium, an acid, an organic base, and a complexing agent.

  17. CCP Astronaut Eric Boe, GOES-S Prepared for Launch

    NASA Image and Video Library

    2018-02-28

    NASA astronaut Eric Boe, one of four astronauts working with the agency’s Commercial Crew Program, had the opportunity to check out the Crew Access Tower at Space Launch Complex 41 (SLC-41) Wednesday with a United Launch Alliance Atlas V on the pad. Boe, along with launch operations engineers from NASA, Boeing, and ULA, climbed the launch pad tower to evaluate lighting and spotlights after dark. The survey helped ensure crew members will have acceptable visibility as they prepare to launch aboard Boeing’s Starliner spacecraft on the Crew Flight Test to the International Space Station targeted for later this year.

  18. Polylactide-co-glycolide nanoparticles for controlled delivery of anticancer agents

    PubMed Central

    Dinarvand, R; Sepehri, N; Manoochehri, S; Rouhani, H; Atyabi, F

    2011-01-01

    The effectiveness of anticancer agents may be hindered by low solubility in water, poor permeability, and high efflux from cells. Nanomaterials have been used to enable drug delivery with lower toxicity to healthy cells and enhanced drug delivery to tumor cells. Different nanoparticles have been developed using different polymers with or without surface modification to target tumor cells both passively and/or actively. Polylactide-co-glycolide (PLGA), a biodegradable polyester approved for human use, has been used extensively. Here we report on recent developments concerning PLGA nanoparticles prepared for cancer treatment. We review the methods used for the preparation and characterization of PLGA nanoparticles and their applications in the delivery of a number of active agents. Increasing experience in the field of preparation, characterization, and in vivo application of PLGA nanoparticles has provided the necessary momentum for promising future use of these agents in cancer treatment, with higher efficacy and fewer side effects. PMID:21720501

  19. Preparation and enhanced daylight-induced photocatalytic activity of C,N,S-tridoped titanium dioxide powders.

    PubMed

    Zhou, Minghua; Yu, Jiaguo

    2008-04-15

    A simple method for preparing highly daylight-induced photoactive nanocrystalline C,N,S-tridoped TiO2 powders was developed by a solid-phase reaction. The as-prepared TiO2 powders were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra, N2 adsorption-desorption measurements and transmission electron microscopy (TEM). The photocatalytic activity was evaluated by the photocatalytic oxidation of formaldehyde under daylight irradiation in air. The results show that daylight-induced photocatalytic activities of the as-prepared TiO2 powders were improved by C,N,S-tridoping. The C,N,S-tridoped TiO2 powders exhibited stronger absorption in the near UV and visible-light region with red shift in the band-gap transition. When the molar ratio of CS(NH2)2 to xerogel TiO2 powders (prepared by hydrolysis of Ti(OC4H9)4 in distilled water) (R) was kept in 3, the daylight-induced photocatalytic activities of the as-prepared C,N,S-tridoped TiO2 powders were about more than six times greater than that of Degussa P25 and un-doped TiO2 powders. The high activities of the C,N,S-tridoped TiO2 can be attributed to the results of the synergetic effects of strong absorption in the near UV and visible-light region, red shift in adsorption edge and two phase structures of un-doped TiO2 and C,N,S-tridoped TiO2.

  20. The U.S. Rosetta Project: Preparations for Prime Mission, 2014

    NASA Technical Reports Server (NTRS)

    Alexander, C.; Chmielewski, A.; Aguinaldo, A. M.; Ko, A.; Accomazzo, A.; Taylor, M. G. G.

    2014-01-01

    In 2014, the International Rosetta mission will place a spacecraft in orbit around comet 67P/Churyumov-Gerasimenko and deliver a lander to the comet's surface. The National Aeronautics and Space Administration's (NASA) contribution to the International Rosetta mission, designated the U.S. Rosetta Project, includes several instruments, tracking support, and science support for some non-US payloads. In July 2011 the spacecraft was placed in a long-duration hibernation mode planned to last approximately 37 months to conserve electrical power. Rosetta will rendezvous with 67P/Churyumov-Gerasimenko in 2014. On the eve of the mission's arrival at its target, this paper highlights three issues related to Rosetta's looming prime mission: (A) measures taken in 2009 to prepare the US Rosetta Project for the long-duration hibernation mode; (B) risk reviews conducted in 2013 to prepare the US Rosetta Project for exit from hibernation; (C) ESA and NASA preparations for use of NASA Deep Space Network (DSN) assets related to keyword files.

  1. Biotemplated preparation of CdS nanoparticles/bacterial cellulose hybrid nanofibers for photocatalysis application.

    PubMed

    Yang, Jiazhi; Yu, Junwei; Fan, Jun; Sun, Dongping; Tang, Weihua; Yang, Xuejie

    2011-05-15

    In this work, we describe a novel facile and effective strategy to prepare micrometer-long hybrid nanofibers by deposition of CdS nanoparticles onto the substrate of hydrated bacterial cellulose nanofibers (BCF). Hexagonal phase CdS nanocrystals were achieved via a simple hydrothermal reaction between CdCl(2) and thiourea at relatively low temperature. The prepared pristine BCF and the CdS/BCF hybrid nanofibers were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-vis absorption spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results reveal that the CdS nanoparticles were homogeneously deposited on the BCF surface and stabilized via coordination effect. The CdS/BCF hybrid nanofibers demonstrated high-efficiency photocatalysis with 82% methyl orange (MO) degradation after 90 min irradiation and good recyclability. The results indicate that the CdS/BCF hybrid nanofibers are promising candidate as robust visible light responsive photocatalysts. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. African American Women’s Preparation for Childbirth From the Perspective of African American Health-Care Providers

    PubMed Central

    Abbyad, Christine; Robertson, Trina Reed

    2011-01-01

    Preparation for birthing has focused primarily on Caucasian women. No studies have explored African American women’s birth preparation. From the perceptions of 12 African American maternity health-care providers, this study elicited perceptions of the ways in which pregnant African American women prepare for childbirth. Focus group participants answered seven semistructured questions. Four themes emerged: connecting with nurturers, traversing an unresponsive system, the need to be strong, and childbirth classes not a priority. Recommendations for nurses and childbirth educators include: (a) self-awareness of attitudes toward African Americans, (b) empowering of clients for birthing, (c) recognition of the role that pregnant women’s mothers play, (d) tailoring of childbirth classes for African American women, and (e) research on how racism influences pregnant African American women’s preparation for birthing. PMID:22211059

  3. Mission planning and simulation via intelligent agents

    NASA Technical Reports Server (NTRS)

    Gargan, Robert A., Jr.; Tilley, Randall W.

    1987-01-01

    A system that can operate from a flight manifest to plan and simulate payload preparation and transport via Shuttle flights is described. The design alternatives and the prototype implementation of the payload hardware and inventory tracking system are discussed. It is shown how intelligent agents can be used to generate mission schedules, and how, through the use of these intelligent agents, knowledge becomes separated into small manageable knowledge bases.

  4. Connexin 43-targeted T1 contrast agent for MRI diagnosis of glioma.

    PubMed

    Abakumova, Tatiana; Abakumov, Maxim; Shein, Sergey; Chelushkin, Pavel; Bychkov, Dmitry; Mukhin, Vladimir; Yusubalieva, Gaukhar; Grinenko, Nadezhda; Kabanov, Alexander; Nukolova, Natalia; Chekhonin, Vladimir

    2016-01-01

    Glioblastoma multiforme is the most aggressive form of brain tumor. Early and accurate diagnosis of glioma and its borders is an important step for its successful treatment. One of the promising targets for selective visualization of glioma and its margins is connexin 43 (Cx43), which is highly expressed in reactive astrocytes and migrating glioma cells. The purpose of this study was to synthesize a Gd-based contrast agent conjugated with specific antibodies to Cx43 for efficient visualization of glioma C6 in vivo. We have prepared stable nontoxic conjugates of monoclonal antibody to Cx43 and polylysine-DTPA ligands complexed with Gd(III), which are characterized by higher T1 relaxivity (6.5 mM(-1) s(-1) at 7 T) than the commercial agent Magnevist® (3.4 mM(-1) s(-1)). Cellular uptake of Cx43-specific T1 contrast agent in glioma C6 cells was more than four times higher than the nonspecific IgG-contrast agent, as detected by flow cytometry and confocal analysis. MRI experiments showed that the obtained agents could markedly enhance visualization of glioma C6 in vivo after their intravenous administration. Significant accumulation of Cx43-targeted contrast agents in glioma and the peritumoral zone led not only to enhanced contrast but also to improved detection of the tumor periphery. Fluorescence imaging confirmed notable accumulation of Cx43-specific conjugates in the peritumoral zone compared with nonspecific IgG conjugates at 24 h after intravenous injection. All these features of Cx43-targeted contrast agents might be useful for more precise diagnosis of glioma and its borders by MRI. Copyright © 2015 John Wiley & Sons, Ltd.

  5. Preparation of ZnS microdisks using chemical bath deposition and ZnS/p-Si heterojunction solar cells

    NASA Astrophysics Data System (ADS)

    Hsiao, Y. J.; Meen, T. H.; Ji, L. W.; Tsai, J. K.; Wu, Y. S.; Huang, C. J.

    2013-10-01

    The synthesis and heterojunction solar cell properties of ZnS microdisks prepared by the chemical bath deposition method were investigated. The ZnS deposited on the p-Si blanket substrate exhibits good coverage. The lower reflectance spectra were found as the thickness of the ZnS film increased. The optical absorption spectra of the 80 °C ZnS microdisk exhibited a band-gap energy of 3.4 eV and the power conversion efficiency (PCE) of the AZO/ZnS/p-Si heterojunction solar cell with a 300 nm thick ZnS film was η=2.72%.

  6. The preparation and degradation performance of CdS photocatalysts to methyl orange solution.

    PubMed

    Duan, Limei; Zhao, Weiqiang; Xu, Ling; Chen, Xiaohong; Lita, A; Liu, Zongrui

    2013-03-01

    In this paper, the CdS samples were prepared using thiourea or sodium sulfide as sulfur source by hydrothermal or solvothermal synthesis method, the results of XRD, TEM and SEM showed all the samples belong to hexagonal CdS nano-material with different morphologies. Using the degradation of methyl orange solution as a model reaction, the photocatalytic performance of different CdS samples was measured, and the samples prepared using thiourea as sulfur source exhibited better photocatalytic activity than those using sodium sulfide as sulfur source. The factors on degradation effect were discussed including the pH value of degradation system and the type of light source. The degradation effect of CdS samples increased with the pH value decreased, and the degradation effect was better when the methyl orange solution was irradiated under sunlight than under 250 W mercury lamp.

  7. Biosynthesis of CdS nanoparticles in banana peel extract.

    PubMed

    Zhou, Guang Ju; Li, Shuo Hao; Zhang, Yu Cang; Fu, Yun Zhi

    2014-06-01

    Cadmium sulfide (CdS) nanoparticles (NPs) were synthesized by using banana peel extract as a convenient, non-toxic, eco-friendly 'green' capping agent. Cadmium nitrate and sodium sulfide are main reagents. A variety of CdS NPs are prepared through changing reaction conditions (banana extracts, the amount of banana peel extract, solution pH, concentration and reactive temperature). The prepared CdS colloid displays strong fluorescence spectrum. X-ray diffraction analysis demonstrates the successful formation of CdS NPs. Fourier transform infra-red (FTIR) spectrogram indicates the involvement of carboxyl, amine and hydroxyl groups in the formation of CdS NPs. Transmission electron microscope (TEM) result reveals that the average size of the NPs is around 1.48 nm.

  8. Preparing ultrafine PbS powders from the scrap lead-acid battery by sulfurization and inert gas condensation

    NASA Astrophysics Data System (ADS)

    Xia, Huipeng; Zhan, Lu; Xie, Bing

    2017-02-01

    A novel method for preparing ultrafine PbS powders involving sulfurization combined with inert gas condensation is developed in this paper, which is applicable to recycle Pb from lead paste of spent lead-acid batteries. Initially, the effects of the evaporation and condensation temperature, the inert gas pressure, the condensation distance and substrate on the morphology of as-obtained PbS ultrafine particles are intensively investigated using sulfur powders and lead particles as reagents. Highly dispersed and homogeneous PbS nanoparticles can be prepared under the optimized conditions which are 1223 K heating temperature, 573 K condensation temperature, 100 Pa inert gas pressure and 60 cm condensation distance. Furthermore, this method is successfully applied to recycle Pb from the lead paste of spent lead acid battery to prepare PbS ultrafine powders. This work does not only provide the theoretical fundamental for PbS preparation, but also provides a novel and efficient method for recycling spent lead-acid battery with high added-value products.

  9. Precursors to radiopharmaceutical agents for tissue imaging

    DOEpatents

    Srivastava, Prem C.; Knapp, Jr., Furn F.

    1988-01-01

    A class of radiolabeled compounds to be used in tissue imaging that exhibits rapid brain uptake, good brain:blood radioactivity ratios, and long retention times. The imaging agents are more specifically radioiodinated aromatic amines attached to dihydropyridine carriers, that exhibit heart as well as brain specificity. In addition to the radiolabeled compounds, classes of compounds are also described that are used as precursors and intermediates in the preparation of the imaging agents.

  10. [Microfungicid--a preparation based on trichoderma viride for plant diseases control].

    PubMed

    Kolombet, L V; Zhigletsova, S K; Derbyshev, V V; Ezhov, D V; Kosareva, N I; Bystrova, E V

    2001-01-01

    A technology was designed for manufacturing a preparation based on Trichoderma viride Pers ex S.F. Gray that strongly suppresses the development of causative agents of certain plant diseases and displays a growth-stimulating activity. Cultivation of the strain in a liquid medium for 18-24 h produced up to 60 g dry biomass per liter nutrient medium. A marketable form created in this work conserves the activity of the mycelial preparation for six months. The preparation is compatible with insecticides (carbofos, vismetrin, talstar, and applaud) and certain fungicides (such as baitan). Tests performed with the liquid form of Mycofungicid (seeds were treated with this preparation at a dose of 20-30 g per metric ton before sowing) showed its high efficiency in protecting cereal crops from plant pathogens. The incidence of plant diseases decreased by 65%, and crop yields increased by 15-20%.

  11. Reading Preparation of Secondary ELA Teachers: A U.S. Survey of State Licensure Requirements

    ERIC Educational Resources Information Center

    Lovette, Gail E.

    2013-01-01

    Secondary teacher preparation in reading in the U.S. has received minimal attention from the research community despite the almost universal implementation of the Common Core State Standards. In response, numerous publications have demanded that secondary teachers be fully prepared to support the needs of struggling readers, especially ELA…

  12. Joint chemical agent detector (JCAD): the future of chemical agent detection

    NASA Astrophysics Data System (ADS)

    Laljer, Charles E.

    2003-08-01

    The Joint Chemical Agent Detector (JCAD) has continued development through 2002. The JCAD has completed Contractor Validation Testing (CVT) that included chemical warfare agent testing, environmental testing, electromagnetic interferent testing, and platform integration validation. The JCAD provides state of the art chemical warfare agent detection capability to military and homeland security operators. Intelligence sources estimate that over twenty countries have active chemical weapons programs. The spread of weapons of mass destruction (and the industrial capability for manufacture of these weapons) to third world nations and terrorist organizations has greatly increased the chemical agent threat to U.S. interests. Coupled with the potential for U.S. involvement in localized conflicts in an operational or support capacity, increases the probability that the military Joint Services may encounter chemical agents anywhere in the world. The JCAD is a small (45 in3), lightweight (2 lb.) chemical agent detector for vehicle interiors, aircraft, individual personnel, shipboard, and fixed site locations. The system provides a common detection component across multi-service platforms. This common detector system will allow the Joint Services to use the same operational and support concept for more efficient utilization of resources. The JCAD detects, identifies, quantifies, and warns of the presence of chemical agents prior to onset of miosis. Upon detection of chemical agents, the detector provides local and remote audible and visual alarms to the operators. Advance warning will provide the vehicle crew and other personnel in the local area with the time necessary to protect themselves from the lethal effects of chemical agents. The JCAD is capable of being upgraded to protect against future chemical agent threats. The JCAD provides the operator with the warning necessary to survive and fight in a chemical warfare agent threat environment.

  13. U.S. Dental Schools' Preparation for the Integrated National Board Dental Examination.

    PubMed

    Duong, Mai-Ly T; Cothron, Annaliese E; Lawson, Nathaniel C; Doherty, Eileen H

    2018-03-01

    An Integrated National Board Dental Examination (INBDE) combining basic, behavioral, and clinical sciences will be implemented in 2020 to replace the current two-part National Board Dental Examination required for all candidates who seek to practice dentistry in the U.S. The aims of this study were to determine how U.S. dental schools are preparing for implementation of the INBDE and to assess their top administrators' attitudes about the new exam. A total of 150 deans, academic deans, and other administrators at all 64 U.S. dental schools with graduating classes in 2016 were emailed a 19-question electronic survey. The survey questions addressed the respondents' level of support, perceived benefits and challenges, and planned preparation strategies for the INBDE. The individual response rate was 59%, representing 57 of the 64 schools. Approximately 60% of the respondents either agreed or strongly agreed that they support the integrated exam, while roughly 25% either somewhat or strongly disagreed. While most respondents (72%) reported that their institutions would be prepared for the INBDE, 74% reported that the merged exam created additional strain for their institutions. Respondents reported viewing content integration and clinical applicability as benefits of the INBDE, while required curriculum changes and student preparedness and stress were seen as challenges. Most of the respondents reported their schools were currently employing strategies to prepare for the INBDE including meetings with faculty and students and changes to curricula and course content. The beginning of the fourth year and the end of the third year were the most frequently reported times when schools planned to require students to take the INBDE, although almost half of the respondents did not yet know what it would be required at their school. Several schools were reconsidering using the boards as a passing requirement. This study found that support for the INBDE was not universal, but

  14. Mechanochemical approach for the capping of mixed core CdS/ZnS nanocrystals: Elimination of cadmium toxicity.

    PubMed

    Bujňáková, Zdenka; Baláž, Matej; Dutková, Erika; Baláž, Peter; Kello, Martin; Mojžišová, Gabriela; Mojžiš, Ján; Vilková, Mária; Imrich, Ján; Psotka, Miroslav

    2017-01-15

    The wet mechanochemical procedure for the capping of the CdS and CdS/ZnS quantum dot nanocrystals is reported. l-cysteine and polyvinylpyrrolidone (PVP) were used as capping agents. When using l-cysteine, the dissolution of cadmium(II) was almost none for CdS/ZnS nanocrystals. Moreover, prepared CdS- and CdS/ZnS-cysteine nanosuspensions exhibited unimodal particle size distributions with very good stability, which was further supported by the zeta potential measurements. The Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy showed the successful embedment of cysteine into the structure of the nanocrystals. Additionally, the optical properties were examined, and the results showed that the cysteine nanosuspension has promising fluorescence properties. On the other hand, PVP was not determined to be a very suitable capping agent for the present system. In this case, the release of cadmium(II) was higher in comparison to the l-cysteine capped samples. The nanosuspensions were successfully used for in vitro studies on selected cancer cell lines. Using fluorescence microscopy, it was evidenced that the nanocrystals enter the cell and that they can serve as imaging agents in biomedical applications. Copyright © 2016. Published by Elsevier Inc.

  15. A novel crosslinking strategy for preparing poly(vinyl alcohol)-based proton-conducting membranes with high sulfonation

    NASA Astrophysics Data System (ADS)

    Tsai, Chun-En; Lin, Chi-Wen; Hwang, Bing-Joe

    This study synthesizes poly(vinyl alcohol) (PVA)-based polymer electrolyte membranes by a two-step crosslinking process involving esterization and acetal ring formation reactions. This work also uses sulfosuccinic acid (SSA) as the first crosslinking agent to form an inter-crosslinked structure and a promoting sulfonating agent. Glutaraldehyde (GA) as the second crosslinking agent, reacts with the spare OH group of PVA and forms, not only a dense structure at the outer membrane surface, but also a hydrophobic protective layer. Compared with membranes prepared by a traditional one-step crosslinking process, membranes prepared by the two-step crosslinking process exhibit excellent dissolution resistance in water. The membranes become water-insoluble even at a molar ratio of SO 3H/PVA-OH as high as 0.45. Moreover, the synthesized membranes also exhibit high proton conductivities and high methanol permeability resistance. The current study measures highest proton conductivity of 5.3 × 10 -2 S cm -1 at room temperature from one of the synthesized membranes, higher than that of the Nafion ® membrane. Methanol permeability of the synthesized membranes measures about 1 × 10 -7 cm 2 S -1, about one order of magnitude lower than that of the Nafion ® membrane.

  16. Preparation of flower-like CuS by solvothermal method for photocatalytic, UV protection and EMI shielding applications

    NASA Astrophysics Data System (ADS)

    Hu, Xiao-Sai; Shen, Yong; Xu, Li-Hui; Wang, Li-Ming; Lu, Li-sha; Zhang, Ya-ting

    2016-11-01

    The flower-like CuS hierarchical structures were synthesized by solvothermal method. The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared(FTIR) spectroscopy, UV-vis optical absorption spectroscopy and thermogravimetric analysis (TGA). The results demonstrated that the as-prepared flower-like CuS with the diameter of 1-5 um was pure hexagonal phase CuS and had well-defined flower-like structures. (1) The as-prepared CuS was proved to possess high photocatalytic performance with band gap of 1.45 eV. The degradation rate of Methylene blue (MB) was up to, 98.26%, 100% after 30 min under UV and visible irradiation. (2)The UPF of cotton fabric treated with CuS reached up to 174 compared with the original untreated fabric with the UPF 20.62. (3) The electromagnetic interference shielding effectiveness (EMI SE) of CuS coating was up to 27-31 dB when the content of CuS increased to 28.6%wt in the frequency of 300 KHz-3 GHz. Furthermore, the influence of reaction conditions on the morphology of the as-prepared CuS was investigated systematically and the possible formation mechanism of the CuS hierarchical structure was also proposed.

  17. Low-Temperature Surface Preparation and Epitaxial Growth of ZnS and Cu 2ZnSnS 4 on ZnS(110) and GaP(100)

    DOE PAGES

    Harvey, Steven P; Wilson, Samual; Moutinho, Helio R; ...

    2017-08-12

    Here we give a summary of the low-temperature preparation methods of ZnS(110) and GaP(100) crystals for epitaxial growth of ZnS and Cu 2ZnSnS 4 (CZTS) via molecular beam epitaxy. Substrates were prepared for epitaxial growth by means of room-temperature aqueous surface treatments and subsequent ultra-high vacuum transfer to the deposition system. Epitaxial growth of ZnS was successful at 500 K on both ZnS(110) and GaP(100) as only single domains were observed with electron backscatter diffraction; furthermore, transmission electron microscopy measurements confirmed an epitaxial interface. Epitaxial growth of CZTS was successful on ZnS at 700 K. However, epitaxial growth was notmore » possible on GaP at 700 K due to Ga xS y formation, which significantly degraded the quality of the GaP crystal surface. Although CZTS was grown epitaxially on ZnS, growth of multiple crystallographic domains remains a problem that could inherently limit the viability of epitaxial CZTS for model system studies.« less

  18. Low-Temperature Surface Preparation and Epitaxial Growth of ZnS and Cu 2ZnSnS 4 on ZnS(110) and GaP(100)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harvey, Steven P; Wilson, Samual; Moutinho, Helio R

    Here we give a summary of the low-temperature preparation methods of ZnS(110) and GaP(100) crystals for epitaxial growth of ZnS and Cu 2ZnSnS 4 (CZTS) via molecular beam epitaxy. Substrates were prepared for epitaxial growth by means of room-temperature aqueous surface treatments and subsequent ultra-high vacuum transfer to the deposition system. Epitaxial growth of ZnS was successful at 500 K on both ZnS(110) and GaP(100) as only single domains were observed with electron backscatter diffraction; furthermore, transmission electron microscopy measurements confirmed an epitaxial interface. Epitaxial growth of CZTS was successful on ZnS at 700 K. However, epitaxial growth was notmore » possible on GaP at 700 K due to Ga xS y formation, which significantly degraded the quality of the GaP crystal surface. Although CZTS was grown epitaxially on ZnS, growth of multiple crystallographic domains remains a problem that could inherently limit the viability of epitaxial CZTS for model system studies.« less

  19. Preparation, quality control and biodistribution assessment of ¹⁵³Sm-BPAMD as a novel agent for bone pain palliation therapy.

    PubMed

    Rabie, Ali; Enayati, Razieh; Yousefnia, Hassan; Jalilian, Amir Reza; Shamsaei, Mojtaba; Zolghadri, Samaneh; Bahrami-Samani, Ali; Hosntalab, Mohammad

    2015-12-01

    Various phosphonate ligands labeled with β(-)-emitting radionuclides have shown good efficacy for bone pain palliation. In this study, a new agent for bone pain palliation has been developed. ¹⁵³Sm-(4-{[(bis(phosphonomethyl))carbamoyl]methyl}-7,10-bis(carboxymethyl)-1,4,7,10-tetraazacyclododec-1-yl) acetic acid (¹⁵³Sm-BPAMD) complex was prepared using BPAMD ligand and ¹⁵³SmCl3. The effect of various parameters on the labeling yield of ¹⁵³Sm-BPAMD including ligand concentration, pH, temperature and reaction time were studied. Radiochemical purity of the radiolabeled complex was checked by instant thin layer chromatography (ITLC). Stability studies of the complex in the final preparation and in the presence of human serum were performed up to 48 h. Partition coefficient and hydroxyapatite (HA) binding of the complex were investigated and biodistribution studies (SPECT imaging and scarification) were performed after injection of the complex to Syrian mice up to 48 h post-injection. The biodistribution of the complex was compared with the biodistribution of the ¹⁵³Sm cation in the same type mice. ¹⁵³Sm-BPAMD was prepared in high radiochemical purity >98% and specific activity of 267 GBq/mmol at the optimal conditions. The complex demonstrated significant stability at room temperature and in human serum at least for 48 h. HA binding assay demonstrated that at the amount of more than 5 mg, approximately, all radiolabeled complex was bound to HA. At the pH 7.4, LogP o/w was -1.86 ± 0.02. Both SPECT and scarification showed major accumulation of the labeled compound in the bone tissue. The results show that ¹⁵³Sm-BPAMD has interesting characteristics as an agent for bone pain palliation; however, further biological studies in other mammals are still needed.

  20. Highly luminescent core-shell InP/ZnX (X = S, Se) quantum dots prepared via a phosphine synthetic route.

    PubMed

    Mordvinova, Natalia; Vinokurov, Alexander; Kuznetsova, Tatiana; Lebedev, Oleg I; Dorofeev, Sergey

    2017-01-24

    Here we report a simple method for the creation of highly luminescent core-shell InP/ZnX (X = S, Se) quantum dots (QDs) on the basis of a phosphine synthetic route. In this method a Zn precursor was added to the reaction mixture at the beginning of the synthesis to form an In(Zn)P alloy structure, which promoted the formation of a ZnX shell. Core-shell InP/ZnX QDs exhibit highly intensive emission with a quantum yield over 50%. The proposed method is primarily important for practical applications. Advantages of this method compared to the widely used SILAR technique are discussed. We further demonstrate that the SILAR approach consisting of consequent addition of Zn and chalcogen precursors to pre-prepared non-doped InP colloidal nanoparticles is not quite suitable for shell growth without the addition of special activator agents or the use of very reactive precursors.

  1. Optimizing the relaxivity of GdIII complexes appended to InP/ZnS quantum dots by linker tuning.

    PubMed

    Stasiuk, Graeme J; Tamang, Sudarsan; Imbert, Daniel; Gateau, Christelle; Reiss, Peter; Fries, Pascal; Mazzanti, Marinella

    2013-06-21

    Three bimodal MRI/optical nanosized contrast agents with high per-nanoparticle relaxivity (up to 2523 mM(-1) s(-1) at 35 MHz and 932 mM(-1) s(-1) at 200 MHz) have been prepared connecting up to 115 tris-aqua Gd(III) complexes to fluorescent non-toxic InP/ZnS quantum dots. The structure of the linker has an important effect on the relaxivity of the final multimeric contrast agent.

  2. 46 CFR Sec. 3 - Preparation of invoices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... NSA ORDER NO. 47 Sec. 3 Preparation of invoices. (a) Pursuant to Article 4 of the Service Agreement... under the applicable provisions of NSA Order No. 47. (1) Invoices shall be prepared so as to show... provisions of NSA Order No. 47 due the undersigned General Agent for the month of _____ under Service...

  3. 46 CFR Sec. 3 - Preparation of invoices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... NSA ORDER NO. 47 Sec. 3 Preparation of invoices. (a) Pursuant to Article 4 of the Service Agreement... under the applicable provisions of NSA Order No. 47. (1) Invoices shall be prepared so as to show... provisions of NSA Order No. 47 due the undersigned General Agent for the month of _____ under Service...

  4. 46 CFR Sec. 3 - Preparation of invoices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... NSA ORDER NO. 47 Sec. 3 Preparation of invoices. (a) Pursuant to Article 4 of the Service Agreement... under the applicable provisions of NSA Order No. 47. (1) Invoices shall be prepared so as to show... provisions of NSA Order No. 47 due the undersigned General Agent for the month of _____ under Service...

  5. 46 CFR Sec. 3 - Preparation of invoices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... NSA ORDER NO. 47 Sec. 3 Preparation of invoices. (a) Pursuant to Article 4 of the Service Agreement... under the applicable provisions of NSA Order No. 47. (1) Invoices shall be prepared so as to show... provisions of NSA Order No. 47 due the undersigned General Agent for the month of _____ under Service...

  6. 46 CFR Sec. 3 - Preparation of invoices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... NSA ORDER NO. 47 Sec. 3 Preparation of invoices. (a) Pursuant to Article 4 of the Service Agreement... under the applicable provisions of NSA Order No. 47. (1) Invoices shall be prepared so as to show... provisions of NSA Order No. 47 due the undersigned General Agent for the month of _____ under Service...

  7. Synthesis, structure, luminescence, and magnetic properties of a single-ion magnet "mer"-[tris(N-[(imidazol-4-yl)-methylidene]-DL-phenylalaninato)terbium(III) and related "fac"-DL-alaninato derivative.

    PubMed

    Yamauchi, Suguru; Fujinami, Takeshi; Matsumoto, Naohide; Mochida, Naotaka; Ishida, Takayuki; Sunatsuki, Yukinari; Watanabe, Masayuki; Tsuchimoto, Masanobu; Coletti, Cecilia; Re, Nazzareno

    2014-06-16

    Two Tb(III) complexes with the same N6O3 donor atoms but different coordination geometries, "fac"-[Tb(III)(HL(DL-ala))3]·7H2O (1) and "mer"-[Tb(III)(HL(DL-phe))3]·7H2O (2), were synthesized, where H2L(DL-ala) and H2L(DL-phe) are N-[(imidazol-4-yl)methylidene]-DL-alanine and -DL-phenylalanine, respectively. Each Tb(III) ion is coordinated by three electronically mononegative NNO tridentate ligands to form a coordination geometry of a tricapped trigonal prism. Compound 1 consists of enantiomers "fac"-[Tb(III)(HL(D-ala))3] and "fac"-[Tb(III)(HL(L-ala))3], while 2 consists of "mer"-[Tb(III)(HL(D-phe))2(HL(L-phe))] and "mer"-[Tb(III)(HL(D-phe))(HL(L-phe))2]. Magnetic data were analyzed by a spin Hamiltonian including the crystal field effect on the Tb(III) ion (4f(8), J = 6, S = 3, L = 3, gJ = 3/2, (7)F6). The Stark splitting of the ground state (7)F6 was evaluated from magnetic analysis, and the energy diagram pattern indicated easy-plane and easy-axis (Ising type) magnetic anisotropies for 1 and 2, respectively. Highly efficient luminescences with Φ = 0.50 and 0.61 for 1 and 2, respectively, were observed, and the luminescence fine structure due to the (5)D4 → (7)F6 transition is in good accordance with the energy diagram determined from magnetic analysis. The energy diagram of 1 shows an approximate single-well potential curve, whereas that of 2 shows a double- or quadruple-well potential within the (7)F6 multiplets. Complex 2 displayed an onset of the out-of-phase signal in alternating current (ac) susceptibility at a direct current bias field of 1000 Oe on cooling down to 1.9 K. A slight frequency dependence was recorded around 2 K. On the other hand, 1 did not show any meaningful out-of-phase ac susceptibility. Pulsed-field magnetizations of 1 and 2 were measured below 1.6 K, and only 2 exhibited magnetic hysteresis. This finding agrees well with the energy diagram pattern from crystal field calculation on 1 and 2. DFT calculation allowed us to estimate the

  8. Production, Quality Control and Biological Evaluation of 166Ho-PDTMP as a Possible Bone Palliation Agent

    PubMed Central

    Zolghadri, Samaneh; Jalilian, Amir Reza; Naseri, Zohreh; Yousefnia, Hassan; Bahrami-Samani, Ali; Ghannadi-Maragheh, Mohammad; Afarideh, Hossein

    2013-01-01

    Objective(s): In this study, 166Ho-1,2-propylene di-amino tetra(methy1enephosphonicAcid) (166Ho-PDTMP) complex was prepared as a bone palliation agent. Materials and Methods: The complex was successfully prepared using an in-house synthesized EDTMP ligand and 166HoCl3. Ho-166 chloride was obtained by thermal neutron irradiation (1 × 1013 n.cm-2.s-1) of natural Ho(NO3)3 samples followed by radiolabeling and stability studies. Biodistribution in wild type rats was also peformed. Results: The complex was prepared with the specific activity of 278 GBq/mg and high radiochemical purity (>99%, checked by ITLC). 166Ho-PDTMP complex was stabilized in the final preparation and in the presence of human serum (>90%) up to 72 hr. The biodistribution of 166Ho-PDTMP in wild-type rats demonstrated significant bone uptake was up to 48 hr compared to 166HoCl3. Conclusion: The produced 166Ho-PDTMP properties suggest a possible new bone palliative therapeutic to overcome the metastatic bone pains. PMID:23826495

  9. Synthesis of cytocompatible Fe3O4@ZSM-5 nanocomposite as magnetic resonance imaging contrast agent

    NASA Astrophysics Data System (ADS)

    Atashi, Zahra; Divband, Baharak; Keshtkar, Ahmad; Khatamian, Maasoumeh; Farahmand-Zahed, Farzane; Nazarlo, Ali Kiani; Gharehaghaji, Nahideh

    2017-09-01

    In this study, ZSM-5 nano zeolite was used as a support material for iron oxide nanoparticles and the potential ability of the nanocomposite for magnetic resonance imaging (MRI) contrast agent was investigated. The nanocomposite was synthesized by hydrothermal method and characterized using X-ray diffraction and scanning electron microscopy. MRI was carried out by use of a 1.5 Tesla clinical scanner. The T2 weighted images were prepared and the r2 relaxivity was calculated. The sizes of Fe3O4 nanoparticles and related nanocomposite were 13-24 nm and 80-150 nm, respectively. Results of MTT assay confirmed that the prepared nanocomposite is cytocompatible. The r2 relaxivity of the Fe3O4@ZSM-5 nanocomposite was 457.1 mM-1 s-1. This study suggests that the Fe3O4@ZSM-5 nanocomposite has potential to use as an MRI T2 contrast agent.

  10. Index of flood maps prepared by the U.S. Geological Survey through 1973

    USGS Publications Warehouse

    Carrigan, Philip Hadley

    1974-01-01

    A listing is presented of flood maps prepared by the U.S. Geological Survey through 1973. Maps are listed by State and county and the list provides information on the type of flooding depicted and the reliability of the delineation.The list was prepared from a computer file, and an available program allows retrieval of data by land-line location, State and county, and Standard Metropolitan Statistical Area (SMSA). The file will be continuously updated.

  11. Vietnamese Victims of Agent Orange and U.S.-Vietnam Relations

    DTIC Science & Technology

    2009-05-28

    Hercules Inc., Monsanto Company, T-H Agricultural & Nutrition Company, Thompson Chemicals Corporation, and Uniroyal Inc. Agent Orange was one of 15...ban the import of agricultural and aquatic goods from Vietnam for health reasons. 85 Tom Fawthrop, “Agent Orange Victims Sue Monsanto ,” Corpwatch

  12. Preparation of NiS/ZnIn2S4 as a superior photocatalyst for hydrogen evolution under visible light irradiation

    PubMed Central

    Wei, Liang; Chen, Yongjuan; Zhao, Jialin

    2013-01-01

    Summary In this study, NiS/ZnIn2S4 nanocomposites were successfully prepared via a facile two-step hydrothermal process. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Their photocatalytic performance for hydrogen evolution under visible light irradiation was also investigated. It was found that the photocatalytic hydrogen evolution activity over hexagonal ZnIn2S4 can be significantly increased by loading NiS as a co-catalyst. The formation of a good junction between ZnIn2S4 and NiS via the two step hydrothermal processes is beneficial for the directional migration of the photo-excited electrons from ZnIn2S4 to NiS. The highest photocatalytic hydrogen evolution rate (104.7 μmol/h), which is even higher than that over Pt/ZnIn2S4 nanocomposite (77.8 μmol/h), was observed over an optimum NiS loading amount of 0.5 wt %. This work demonstrates a high potential of the developing of environmental friendly, cheap noble-metal-free co-catalyst for semiconductor-based photocatalytic hydrogen evolution. PMID:24455453

  13. Benzamide Derivatives as Protective Agents against the Action of Xenotoxic Agents on Human Cells.

    DTIC Science & Technology

    1984-05-31

    4D-AlI45 396 BENZAMIDE DERIVATIVES AS PROTECTIVE AGENTS AGAINST THE I/i ACTION OF XENOTOXI..(U) OHIO STATE UNIV RESEARCH I FOUNDATION COLUMBUS G E...AS PROTECTIVE AGENTS AGAINST THE ACTION OF XENOTOXIC AGENTS ON HUMAN CELLS CD George E. Milo * Department of Physiological Chemistry and...TITLE (and Subtitle) S. .YPE OF REPORT & PERIOD COVERED Benzamide Derivatives as Protective Agents Annual Scientific Report 5 Against the Action of

  14. Preparation, spectral, X-ray powder diffraction and computational studies and genotoxic properties of new azo-azomethine metal chelates

    NASA Astrophysics Data System (ADS)

    Bitmez, Şirin; Sayin, Koray; Avar, Bariş; Köse, Muhammet; Kayraldız, Ahmet; Kurtoğlu, Mükerrem

    2014-11-01

    A new tridentate azo-azomethine ligand, N‧-[{2-hydroxy-5-[(4-nitrophenyl)diazenyl]phenyl}methylidene]benzohydrazidemonohydrate, (sbH·H2O) (1), is prepared by condensation of benzohydrazide and 2-hydroxy-5-[(4-nitrophenyl)diazenyl]benzaldehyde (a) with treatment of a solution of diazonium salt of p-nitroaniline and 2-hydroxybenzaldehyde in EtOH. The five coordination compounds, [Co(sb)2]·4H2O (2), [Ni(sb)2]·H2O (3), [Cu(sb)2]·4H2O (4), [Zn(sb)2]·H2O (5) and [Cd(sb)2]·H2O (6) are prepared by reacting the Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) ions with the ligand. The structures of the compounds are elucidated from the elemental analyses data and spectroscopic studies. It is found the ligand acts as a tridentate bending through phenolic and carbonyl oxygens and nitrogen atom of the Cdbnd Nsbnd group similar to the most of salicylaldimines. Comparison of the infrared spectra of the ligand and its metal complexes confirm that azo-Schiff base behaves as a monobasic tridentate ligand towards the central metal ion with an ONO donor sequence. Upon complexation with the ligand, the Cd(II), and Zn(II) ions form monoclinic structures, while Co(II), Cu(II) and Ni(II) ions form orthorhombic structures. Quantum chemical calculations are performed on tautomers and its metal chelates by using DFT/B3LYP method. Most stable tautomer is determined as tautomer (1a). The geometrical parameters of its metal chelates are obtained as theoretically. The NLO properties of tautomer (1a) and its metal complexes are investigated. Finally, the ligand and its metal complexes are assessed for their genotoxicity.

  15. Zirconium doped nano-dispersed oxides of Fe, Al and Zn for destruction of warfare agents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stengl, Vaclav, E-mail: stengl@uach.cz; Houskova, Vendula; Bakardjieva, Snejana

    2010-11-15

    Zirconium doped nano dispersive oxides of Fe, Al and Zn were prepared by a homogeneous hydrolysis of the respective sulfate salts with urea in aqueous solutions. Synthesized metal oxide hydroxides were characterized using Brunauer-Emmett-Teller (BET) surface area and Barrett-Joiner-Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDX). These oxides were taken for an experimental evaluation of their reactivity with sulfur mustard (HD or bis(2-chloroethyl)sulfide), soman (GD or (3,3'-Dimethylbutan-2-yl)-methylphosphonofluoridate) and VX agent (S-[2-(diisopropylamino)ethyl]-O-ethyl-methylphosphonothionate). The presence of Zr{sup 4+} dopant can increase both the surface area and the surface hydroxylation of the resultingmore » doped oxides, decreases their crystallites' sizes thereby it may contribute in enabling the substrate adsorption at the oxide surface thus it can accelerate the rate of degradation of warfare agents. Addition of Zr{sup 4+} converts the product of the reaction of ferric sulphate with urea from ferrihydrite to goethite. We found out that doped oxo-hydroxides Zr-FeO(OH) - being prepared by a homogeneous hydrolysis of ferric and zirconium oxo-sulfates mixture in aqueous solutions - exhibit a comparatively higher degradation activity towards chemical warfare agents (CWAs). Degradation of soman or VX agent on Zr-doped FeO(OH) containing ca. 8.3 wt.% of zirconium proceeded to completion within 30 min.« less

  16. Antimicrobial activity of topical anaesthetic preparations.

    PubMed Central

    Badenoch, P R; Coster, D J

    1982-01-01

    Eight commercial topical anaesthetic preparations were tested for their ability to inhibit microbial growth in vitro by incubating serial dilutions with each of 4 micro-organisms. In addition corneas of mice were infected with Staphylococcus aureus, and the effect of the anaesthetics on isolation rates of bacteria was investigated. The preparations were shown to have a wide range of antimicrobial activity, correlating both with the active agents and the preservatives. We suggest that some preparations are unsuitable for use prior to collection of specimens from human corneal ulcers. PMID:6805500

  17. S - and N-alkylating agents diminish the fluorescence of fluorescent dye-stained DNA.

    PubMed

    Giesche, Robert; John, Harald; Kehe, Kai; Schmidt, Annette; Popp, Tanja; Balzuweit, Frank; Thiermann, Horst; Gudermann, Thomas; Steinritz, Dirk

    2017-01-25

    Sulfur mustard (SM), a chemical warfare agent, causes DNA alkylation, which is believed to be the main cause of its toxicity. SM DNA adducts are commonly used to verify exposure to this vesicant. However, the required analytical state-of-the-art mass-spectrometry methods are complex, use delicate instruments, are not mobile, and require laboratory infrastructure that is most likely not available in conflict zones. Attempts have thus been made to develop rapid detection methods that can be used in the field. The analysis of SM DNA adducts (HETE-G) by immunodetection is a convenient and suitable method. For a diagnostic assessment, HETE-G levels must be determined in relation to the total DNA in the sample. Total DNA can be easily visualized by the use of fluorescent DNA dyes. This study examines whether SM and related compounds affect total DNA staining, an issue that has not been investigated before. After pure DNA was extracted from human keratinocytes (HaCaT cells), DNA was exposed to different S- and N-alkylating agents. Our experiments revealed a significant, dose-dependent decrease in the fluorescence signal of fluorescent dye-stained DNA after exposure to alkylating agents. After mass spectrometry and additional fluorescence measurements ruled out covalent modifications of ethidium bromide (EthBr) by SM, we assumed that DNA crosslinks caused DNA condensation and thereby impaired access of the fluorescent dyes to the DNA. DNA digestion by restriction enzymes restored fluorescence, a fact that strengthened our hypothesis. However, monofunctional agents, which are unable to crosslink DNA, also decreased the fluorescence signal. In subsequent experiments, we demonstrated that protons produced during DNA alkylation caused a pH decrease that was found responsible for the reduction in fluorescence. The use of an appropriate buffer system eliminated the adverse effect of alkylating agents on DNA staining with fluorescent dyes. An appropriate buffer system is thus

  18. Sample preparation and detection device for infectious agents

    DOEpatents

    Miles, Robin R.; Wang, Amy W.; Fuller, Christopher K.; Lemoff, Asuncion V.; Bettencourt, Kerry A.; Yu, June

    2003-06-10

    A sample preparation and analysis device which incorporates both immunoassays and PCR assays in one compact, field-portable microchip. The device provides new capabilities in fluid and particle control which allows the building of a fluidic chip with no moving parts, thus decreasing fabrication cost and increasing the robustness of the device. The device can operate in a true continuous (not batch) mode. The device incorporates magnetohydrodynamic (MHD) pumps to move the fluid through the system, acoustic mixing and fractionation, dielectropheretic (DEP) sample concentration and purification, and on-chip optical detection capabilities.

  19. Synthesis and characterization of ZnS with controlled amount of S vacancies for photocatalytic H2 production under visible light

    PubMed Central

    Wang, Gang; Huang, Baibiao; Li, Zhujie; Lou, Zaizhu; Wang, Zeyan; Dai, Ying; Whangbo, Myung-Hwan

    2015-01-01

    Controlling amount of intrinsic S vacancies was achieved in ZnS spheres which were synthesized by a hydrothermal method using Zn and S powders in concentrated NaOH solution with NaBH4 added as reducing agent. These S vacancies efficiently extend absorption spectra of ZnS to visible region. Their photocatalytic activities for H2 production under visible light were evaluated by gas chromatograph, and the midgap states of ZnS introduced by S vacancies were examined by density functional calculations. Our study reveals that the concentration of S vacancies in the ZnS samples can be controlled by varying the amount of the reducing agent NaBH4 in the synthesis, and the prepared ZnS samples exhibit photocatalytic activity for H2 production under visible-light irradiation without loading noble metal. This photocatalytic activity of ZnS increases steadily with increasing the concentration of S vacancies until the latter reaches an optimum value. Our density functional calculations show that S vacancies generate midgap defect states in ZnS, which lead to visible-light absorption and responded. PMID:25712901

  20. Process for the preparation of organoclays

    DOEpatents

    Chaiko, David J.

    2003-01-01

    A method for preparing organoclays from smectites for use as rheological control agents and in the preparation of nanocomposites. Typically, the clay is dispersed in water, and a substantially monomolecular layer of a water soluble polymer is applied to the surfaces of the clay. A surfactant is also applied to the clay to modify the surface hydrophilic/hydrophobic balance of the clay, and the organoclay is separated out for subsequent use.

  1. Agents for replacement of NAD+/NADH system in enzymatic reactions

    DOEpatents

    Fish, Richard H.; Kerr, John B.; Lo, Christine H.

    2004-04-06

    Novel agents acting as co-factors for replacement of NAD(P).sup.+ /NAD(P)H co-enzyme systems in enzymatic oxido-reductive reactions. Agents mimicking the action of NAD(P).sup.+ /NAD(P)H system in enzymatic oxidation/reduction of substrates into reduced or oxidized products. A method for selection and preparation of the mimicking agents for replacement of NAD(P).sup.+ /NAD(P)H system and a device comprising co-factors for replacement of NAD(P).sup.+ /NAD(P)H system.

  2. Effects of coordination agents on the morphology of CdS nanocrystallites synthesized by the hydrothermal method

    NASA Astrophysics Data System (ADS)

    Nie, Qiulin; Yuan, Qiuli; Chen, Weixiang; Xu, Zhude

    2004-05-01

    CdS nanocrystallites were synthesized by the hydrothermal method and characterized by XRD, TEM, and XPS, respectively. Different coordination agents were chosen as the template to investigate their effects on the product morphology. It was found that the CdS nanocrystallites displayed a rod-like shape when ethylenediamine or methylamine were employed as the template. In contrast, only nanoparticles of CdS were observed when ammonia or pyridine were used. Based on our experimental results, a complex structure-controlling mechanism is proposed.

  3. Preparation and characterization of Chitosan/Konjac glucomannan/CdS nanocomposite film with low infrared emissivity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Feng-Ying; Zhou, Yu-Ming, E-mail: fchem@seu.edu.cn; Sun, Yan-qing

    Novel organic-inorganic nanocomposite films were prepared with Chitosan (CS), Konjac glucomannan (KGM) and CdS by one-step synthesis. As-prepared films were characterized by IR spectra, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and infrared emissometer (IR). The results indicated that grown CdS dendrites were formed with reaction time of 12 h for Cd{sup 2+} and CS/KGM, and were well dispersed in CS/KGM with an average diameter of 40 nm. The CS/KGM/CdS nanocomposite films had significantly low infrared emissivity. When the mole ratio of CdS to summation of CS and KGM construction units was 1.0 with CdS size of 10-20 nm,more » the film got the lowest infrared emissivity value of 0.011, which could be attributed to the strong synergism effect existing between CS/KGM and CdS dendrites.« less

  4. Optimal preparation-to-colonoscopy interval in split-dose PEG bowel preparation determines satisfactory bowel preparation quality: an observational prospective study.

    PubMed

    Seo, Eun Hee; Kim, Tae Oh; Park, Min Jae; Joo, Hee Rin; Heo, Nae Yun; Park, Jongha; Park, Seung Ha; Yang, Sung Yeon; Moon, Young Soo

    2012-03-01

    Several factors influence bowel preparation quality. Recent studies have indicated that the time interval between bowel preparation and the start of colonoscopy is also important in determining bowel preparation quality. To evaluate the influence of the preparation-to-colonoscopy (PC) interval (the interval of time between the last polyethylene glycol dose ingestion and the start of the colonoscopy) on bowel preparation quality in the split-dose method for colonoscopy. Prospective observational study. University medical center. A total of 366 consecutive outpatients undergoing colonoscopy. Split-dose bowel preparation and colonoscopy. The quality of bowel preparation was assessed by using the Ottawa Bowel Preparation Scale according to the PC interval, and other factors that might influence bowel preparation quality were analyzed. Colonoscopies with a PC interval of 3 to 5 hours had the best bowel preparation quality score in the whole, right, mid, and rectosigmoid colon according to the Ottawa Bowel Preparation Scale. In multivariate analysis, the PC interval (odds ratio [OR] 1.85; 95% CI, 1.18-2.86), the amount of PEG ingested (OR 4.34; 95% CI, 1.08-16.66), and compliance with diet instructions (OR 2.22l 95% CI, 1.33-3.70) were significant contributors to satisfactory bowel preparation. Nonrandomized controlled, single-center trial. The optimal time interval between the last dose of the agent and the start of colonoscopy is one of the important factors to determine satisfactory bowel preparation quality in split-dose polyethylene glycol bowel preparation. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  5. Preparation of demipermanent and semipermanent hair dyes gels from ethanol extract of Caesalpinia sappan L. using carbomer as gelling agent

    NASA Astrophysics Data System (ADS)

    Indrawati, T.; Syahrin, A.; Irpan

    2017-07-01

    Caesalpinia sappan L. (Cs L) contains of essential oils, saponin, brazilin, brazilein, alkaloids, flavonoids and tannins that have a function as cationic natural dyes. The aim of this research was to prepare the ethanol extract of Cs L wood and to prepare demi-permanent and semi-permanent of hair dye gels by using Carbomer of 2 % and 1.5 % as gelling agent and Cs L extract as cationic dyes. The Extract of Cs L was macerated by using ethanol of 96 % as the solvent, and then thickened. Three formula of demi-permanent hair dye gels were made by using Cs L extract of 3 %, 6% and 9 %. Three formula of semi-permanent hair dye gels were made by using Cs L extract of 2.50 %, 7.00 % and 10.50 %. Those hair dyes gels were prepared by swelling and mixing methods. All products of hair dyes gels were evaluated with organoleptic test, homogeneity test, pH test, consistency test, rheological properties test and dyeing effect test. The demi-permanent hair dye gels products had brown to brown dark black colors, pH of 5.05-5.43, homogeny, specific Cs L odor, and had pseudoplastic thixotropic flow characteristic. The semi-permanent hair dye gels products had red color pH of 6.5-6.25, homogeny, Cs L odor, and have pseudoplastic thixotropic flow characteristics. The optimum formula of demi-permanent was formula gel that contained of 6 % extract of Cs L and the optimum formula of permanent hair dyes gel was formula that contained of 10.50 % extract of Cs L.

  6. Preparation of theophylline inhalable microcomposite particles by wet milling and spray drying: The influence of mannitol as a co-milling agent.

    PubMed

    Malamatari, Maria; Somavarapu, Satyanarayana; Kachrimanis, Kyriakos; Bloxham, Mark; Taylor, Kevin M G; Buckton, Graham

    2016-11-30

    Inhalable theophylline particles with various amounts of mannitol were prepared by combining wet milling in isopropanol followed by spray drying. The effect of mannitol as a co-milling agent on the micromeritic properties, solid state and aerosol performance of the engineered particles was investigated. Crystal morphology modelling and geometric lattice matching calculations were employed to gain insight into the intermolecular interactions that may influence the mechanical properties of theophylline and mannitol. The addition of mannitol facilitated the size reduction of the needle-like crystals of theophylline and also their assembly in microcomposites by forming a porous structure of mannitol nanocrystals wherein theophylline particles are embedded. The microcomposites were found to be in the same crystalline state as the starting material(s) ensuring their long-term physical stability upon storage. Incorporation of mannitol resulted in microcomposite particles with smaller size, more spherical shape and increased porosity. The aerosol performance of the microcomposites was markedly enhanced compared to the spray-dried suspension of theophylline wet milled without mannitol. Overall, wet co-milling with mannitol in an organic solvent followed by spray drying may be used as a formulation approach for producing respirable particles of water-soluble drugs or drugs that are prone to crystal transformation in an aqueous environment (i.e. formation of hydrates). Copyright © 2016. Published by Elsevier B.V.

  7. Ultrasonic chemical synthesis of CdS-reduced graphene oxide nanocomposites with an enhanced visible light photoactivity

    NASA Astrophysics Data System (ADS)

    Lin, Yi-Chen; Tsai, Du-Cheng; Chang, Zue-Chin; Shieu, Fuh-Sheng

    2018-05-01

    In this study, we report a facile ultrasonic method to prepare a series of CdS and reduced graphene oxide (CdS/rGO) composites with different weight ratios of graphene at temperature as low as 70 °C for 20 min by employing ammonia as a complexing agent of Cd2+ ions and reducing agent of graphene oxide (GO). Pure CdS particles had a poor crystallinity and aggregated to large particles size. As GO was incorporated into CdS, a uniform dispersion of CdS particles with high crystallinity on rGO sheets was clearly observed. The as-prepared CdS/rGO composites have a wide and strong photo absorption in the visible region and display a substantially improved photocatalytic activity for the degradation of methylene blue under visible light irradiation by forming a heterojunction of rGO and CdS. However, too much rGO will shield the light of the active sites for the CdS nanoparticle surface and thus limit further improvement in the photocatalytic efficiency.

  8. Sodium hydrogen carbonate as an alternative blowing agent in the preparation of palm-based polyurethane foam

    NASA Astrophysics Data System (ADS)

    Shakir, Amira Shakim Abdul; Badri, Khairiah Haji; Hua, Chia Chin

    2016-11-01

    An environmental-friendly blowing agent has been used to fabricate flexible polyurethane (PU) foam. Polyurethane foam was prepared from palm kernel oil-based monoester polyol (PKO-p) via prepolymerization method. Acetone has been used as solvent in this study. The developed polyurethane foam was characterized using tensile, differential scanning calorimetry analysis (DSC), thermogravimetric analysis (TGA), optical microscope and drop shape analyzer. The mechanical properties of the PU-reference (PU-R) and PU-NaHCO3 foam was analyzed by tensile using ASTM D 3574-01. From the results, the elongation of PU- NaHCO3 shows reduction to 26.3 % compared to PU-R. The DSC showed two glass transition temperatures in all samples that belonged to the PU-R and PU-NaHCO3. TGA revealed that the incorporation of sodium hydrogen carbonate into the PU system did not show significant difference as compared to the control PU. The morphology of both PU was investigated using optical microscope. Contact angle has been measured to determine the hydrophobicity of the PU. The PU- NaHCO3 exhibited an increase in contact angle (93.1°).

  9. Preparation, properties and anticancer effects of mixed As4S4/ZnS nanoparticles capped by Poloxamer 407.

    PubMed

    Bujňáková, Z; Baláž, M; Zdurienčíková, M; Sedlák, J; Čaplovičová, M; Čaplovič, Ľ; Dutková, E; Zorkovská, A; Turianicová, E; Baláž, P; Shpotyuk, O; Andrejko, S

    2017-02-01

    Arsenic sulfide compounds have a long history of application in a traditional medicine. In recent years, realgar has been studied as a promising drug in cancer treatment. In this study, the arsenic sulfide (As 4 S 4 ) nanoparticles combined with zinc sulfide (ZnS) ones in different molar ratio have been prepared by a simple mechanochemical route in a planetary mill. The successful synthesis and structural properties were confirmed and followed via X-ray diffraction and high-resolution transmission electron microscopy measurements. The morphology of the particles was studied via scanning electron microscopy and transmission electron microscopy methods and the presence of nanocrystallites was verified. For biological tests, the prepared As 4 S 4 /ZnS nanoparticles were further milled in a circulation mill in a water solution of Poloxamer 407 (0.5wt%), in order to cover the particles with this biocompatible copolymer and to obtain stable nanosuspensions with unimodal distribution. The average size of the particles in the nanosuspensions (~120nm) was determined by photon cross-correlation spectroscopy method. Stability of the nanosuspensions was determined via particle size distribution and zeta potential measurements, confirming no physico-chemical changes for several months. Interestingly, with the increasing amount of ZnS in the sample, the stability was improved. The anti-cancer effects were tested on two melanoma cell lines, A375 and Bowes, with promising results, confirming increased efficiency of the samples containing both As 4 S 4 and ZnS nanocrystals. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Process for the preparation of organoclays

    DOEpatents

    Chaiko, David J.

    2004-11-23

    A method for preparing organoclays for use as rheological control agents and in the preparation of nanocomposites. Typically, the clay is dispersed in water, and a specific amount of polymeric hydrotrope, ranging from 0.1 to 15 weight percent relative to the weight of the clay, is adsorbed onto the clay surface. Quaternary amine exchange is also performed on the clay to modify the surface hydrophilic/lipophilic balance (HLB) of the clay.

  11. Characterization of Cu2ZnSnS4 thin films prepared by photo-chemical deposition

    NASA Astrophysics Data System (ADS)

    Moriya, Katsuhiko; Watabe, Jyunichi; Tanaka, Kunihiko; Uchiki, Hisao

    2006-09-01

    Cu2ZnSnS4 (CZTS) thin films were prepared by post-annealing films of metal sulfides of Cu2S, ZnS and SnS2 precursors deposited on soda-lime glass substrates by photo-chemical deposition (PCD) from aqueous solution containing CuSO4, ZnSO4, SnSO4 and Na2S2O3. In this study, sulfurization was employed to prepare high quality CZTS thin films. Deposited films of metal sulfides were annealed in a furnace in an atmosphere of N2 or N2+H2S(5%) at the temperature of 300°, 400° or 500 °C. The sulfured films showed X-ray diffraction peaks from (112), (220), and (312) planes of CZTS and the peaks became sharp by an increase in the sulfurization temperature. CZTS thin film annealed in atmosphere of N2 was S-poor. After annealing atmosphere was changed from N2 into N2+H2S(5%), the decrease of a composi- tional ratio of sulfur could be suppressed.

  12. Joffre’s Second Chance: Leadership in Preparing for and Conducting War

    DTIC Science & Technology

    2010-04-07

    Preparing for and Conducting N /A War Sb. GRANT NUMBER N /A 5c. PROGRAM ELEMENT NUMBER N /A 6. AUTHOR(S) 5d. PROJECT NUMBER MajorEdwardC...Greeley_, United StatesMarine _ _Gg_rps __ ·-"-·- .. N /A ---~···· .. ·-- - --~-- -- ---- - --------~-" --~-- ------- ·-- -·- --- . . .. --~ ·- 5e. TASK...NUMBER N /A 5f. WORK UNIT NUMBEfl. N /A 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) a. PERFORMING ORGANIZATION USMC Command and Staff College

  13. S100B Protein concentration in milk-formulas for preterm and term infants. Correlation with industrial preparation procedures.

    PubMed

    Nigro, Francesco; Gagliardi, Luigi; Ciotti, Sabina; Galvano, Fabio; Pietri, Amedeo; Tina, Gabriella Lucia; Cavallaro, Daniela; La Fauci, Luca; Iacopino, Leonardo; Bognanno, Matteo; Li Volti, Giovanni; Scacco, Antonio; Michetti, Fabrizio; Gazzolo, Diego

    2008-05-01

    Human milk S100B protein possesses important neurotrophic properties. However, in some conditions human milk is substituted by milk formulas. The aims of the present study were: to assess S100B concentrations in milk formulas, to verify any differences in S100B levels between preterm and term infant formulas and to evaluate the impact of industrial preparation at predetermined phases on S100B content. Two different set of samples were tested: (i) commercial preterm (n = 36) and term (n = 36) infant milk formulas; ii) milk preterm (n = 10) and term infant (n = 10) formulas sampled at the following predetermined industrial preparation time points: skimmed cow milk (Time 0); after protein sources supplementation (Time 1); after pasteurization (Time 2); after spray-drying (Time 3). Our results showed that S100B concentration in preterm formulas were higher than in term ones (p < 0.01). In addition, S100B concentrations during industrial preparation showed a significant increase (p < 0.001) at Time 1 followed by a slight decrease (p > 0.05) at Time 2, whereas a significant (p < 0.001) dip was observed at Time 3. In conclusion, S100B showed a sufficient thermostability to resist pasteurization but not spry-drying. New feeding strategies in preterm and term infants are therefore warranted in order to preserve S100B protein during industrial preparation.

  14. Possible Long-Term Health Effects of Short-Term Exposure to Chemical Agents. Volume 3. Current Health Status of Test Subjects

    DTIC Science & Technology

    1985-12-31

    AtMfh.D y) S. PAai COUNTFinal FROM B2/11/1 "rS/1 9l/1 85/12/31 104 i. URNOTATION Report prepared under contracts titled " Study of Possible Long-Term...Effects of Chemical Agents Used in Human Testing--Morbidity Studies " (DAMD17-83-C-3185-- (over) _____________________ CODSS. SUBJECT TERMS (ConteW an en e... study that investigated possible € delayed ’and long-term effects of experimental chemicals administered to soldiers at the U.S. SArmy Laboratories

  15. ZnS Buffer Layers Grown by Modified Chemical Bath Deposition for CIGS Solar Cells

    NASA Astrophysics Data System (ADS)

    Lee, Dongchan; Ahn, Heejin; Shin, Hyundo; Um, Youngho

    2018-03-01

    ZnS thin films were prepared by the chemical bath deposition method using disodium ethylene-diaminetetraacetic acid and hexamethylenetetramine as complexing agents in acidic conditions. The film prepared using a preheated S-ion source showed full surface coverage, but some clusters were found that were generated by the cluster-by-cluster reaction mechanism. On the other hand, the film prepared without this source had a uniform, dense, and smooth surface and showed fewer clusters than the film prepared using a preheated S-ion source. The x-ray photoelectron spectroscopy spectra showed the energy core levels of Zn, O, and S components, and Zn-OH bonding decreased on the film using the preheated S-ion source. Especially, various binding energy peaks were found in the Zn 2p 3/2 spectrum by Gaussian function fitting, and no peak corresponding to Zn-OH bonding was found for the film prepared using a preheated S-ion source. Moreover, the x-ray diffraction spectrum of the ZnS thin film using a non-preheated S-ion source showed amorphous or nanoscale crystallinity, but the emission peaks indicated that the structure of the film using preheated S-ion source was zincblende.

  16. ZnS Buffer Layers Grown by Modified Chemical Bath Deposition for CIGS Solar Cells

    NASA Astrophysics Data System (ADS)

    Lee, Dongchan; Ahn, Heejin; Shin, Hyundo; Um, Youngho

    2018-07-01

    ZnS thin films were prepared by the chemical bath deposition method using disodium ethylene-diaminetetraacetic acid and hexamethylenetetramine as complexing agents in acidic conditions. The film prepared using a preheated S-ion source showed full surface coverage, but some clusters were found that were generated by the cluster-by-cluster reaction mechanism. On the other hand, the film prepared without this source had a uniform, dense, and smooth surface and showed fewer clusters than the film prepared using a preheated S-ion source. The x-ray photoelectron spectroscopy spectra showed the energy core levels of Zn, O, and S components, and Zn-OH bonding decreased on the film using the preheated S-ion source. Especially, various binding energy peaks were found in the Zn 2 p 3/2 spectrum by Gaussian function fitting, and no peak corresponding to Zn-OH bonding was found for the film prepared using a preheated S-ion source. Moreover, the x-ray diffraction spectrum of the ZnS thin film using a non-preheated S-ion source showed amorphous or nanoscale crystallinity, but the emission peaks indicated that the structure of the film using preheated S-ion source was zincblende.

  17. Evaluation of Adhesive Bonding of Lithium Disilicate Ceramic Material with Duel Cured Resin Luting Agents

    PubMed Central

    Gundawar, Sham M.; Radke, Usha M.

    2015-01-01

    Purpose: The purpose of this vitro study was to comparatively evaluate the adhesive bonding of dual cured resin luting agents with lithium disilicate ceramic material. Materials and Methods: Porcelain laminate veneers were prepared with lithium disilicate ceramic material i.e. IPS Empress II( E-Max Press). These laminates were bonded with RelyX ARC, Panavia F 2.0, Variolink II, Duolink and Nexus NX3.The porcelain laminates were etched with 9.6% hydrofluoric acid (Pulpdent Corporation) for one minute, washed for 15 sec with three way syringe and dried for 15 sec with air syringe. The silane (Ultradent) was applied with the help of applicator tip in a single coat and kept undisturbed for one minute. The prepared surfaces of the premolars were treated with 37% phosphoric acid (Prime dent) for 15 sec, thoroughly rinsed and dried as per manufactures instructions. The shear bond test was carried out on all samples with the Universal testing machine (Instron U.S.A.) The scanning electron microscopic study was performed at the fractured interface of representative samples from each group of luting agents. Result: In this study, the highest value of shear bond strength was obtained for NEXUS NX3 and the lowest for VARIOLINK II. Conclusion: The difference in bond strength can be interpreted as the difference in fracture resistance of luting agents, to which shearing load was applied during the shear bond strength test. It is inferred from this study that the composition of the luting agent determines the adhesive characteristics in addition to surface treatment and bonding surface area. PMID:25859514

  18. A comprehensive review on removal of arsenic using activated carbon prepared from easily available waste materials.

    PubMed

    Mondal, Monoj Kumar; Garg, Ravi

    2017-05-01

    Arsenic contamination in water bodies is a serious problem and causes various health problems due to which US Environment Protection Agency (USEPA) set its maximum permissible limit of 10 ppb. The present review article starts with the removal of toxic arsenic using adsorbents prepared from easily available waste materials. Adsorbent either commercial or low-cost adsorbent can be used for arsenic removal but recent research was focused on the low-cost adsorbent. Preparation and activation of various adsorbents were discussed. Adsorption capacities, surface area, thermodynamic, and kinetics data of various adsorbents for As(III) and As(V) removal were compiled. Desorption followed by regeneration and reuse of adsorbents is an important step in adsorption and leads to economical process. Various desorbing and regenerating agents were discussed for arsenic decontamination from the adsorbent surface. Strong acids, bases, and salts are the main desorbing agents. Disposal of arsenic-contaminated adsorbent and arsenic waste was also a big problem because of the toxic and leaching effect of arsenic. So, arsenic waste was disposed of by proper stabilization/solidification (S/S) technique by mixing it in Portland cement, iron, ash, etc. to reduce the leaching effect.

  19. Comparison of preparation of curved root canals with Hyflex CM and Revo-S rotary nickel-titanium instruments.

    PubMed

    Bürklein, S; Börjes, L; Schäfer, E

    2014-05-01

    To compare the shaping ability of three different nickel-titanium rotary instruments during the preparation of curved root canals in extracted teeth. A total of 60 root canals with curvatures ranging between 25° and 35° were divided into three groups of 20 canals. Based on radiographs taken prior to instrumentation, the groups were balanced with respect to the angle and the radius of canal curvature. Canals were prepared to a final apical size of 35 using Mtwo, Hyflex CM, and Revo-S. Using pre- and post-instrumentation radiographs, straightening of the canal curvatures was determined with a computer image analysis program. Preparation time, changes of working length and instrument failures were also recorded. These data were analysed statistically using anova and Student-Newman-Keuls test. During preparation, no file fractured. Mtwo and Hyflex CM maintained the original canal curvature significantly better than Revo-S (P < 0.05). Instrumentation with Mtwo and Hyflex CM was significantly faster than with Revo-S and resulted in less loss of working length (P < 0.05), whilst no significant differences were obtained between Mtwo and Hyflex CM (P > 0.05). Under the conditions of this study, Mtwo and Hyflex CM respected the original canal curvature well and were safe to use. The use of Revo-S instruments required more time to prepare the curved canals and resulted in more pronounced canal straightening compared with Mtwo and Hyflex CM. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  20. A Micro-Level Data-Calibrated Agent-Based Model: The Synergy between Microsimulation and Agent-Based Modeling.

    PubMed

    Singh, Karandeep; Ahn, Chang-Won; Paik, Euihyun; Bae, Jang Won; Lee, Chun-Hee

    2018-01-01

    Artificial life (ALife) examines systems related to natural life, its processes, and its evolution, using simulations with computer models, robotics, and biochemistry. In this article, we focus on the computer modeling, or "soft," aspects of ALife and prepare a framework for scientists and modelers to be able to support such experiments. The framework is designed and built to be a parallel as well as distributed agent-based modeling environment, and does not require end users to have expertise in parallel or distributed computing. Furthermore, we use this framework to implement a hybrid model using microsimulation and agent-based modeling techniques to generate an artificial society. We leverage this artificial society to simulate and analyze population dynamics using Korean population census data. The agents in this model derive their decisional behaviors from real data (microsimulation feature) and interact among themselves (agent-based modeling feature) to proceed in the simulation. The behaviors, interactions, and social scenarios of the agents are varied to perform an analysis of population dynamics. We also estimate the future cost of pension policies based on the future population structure of the artificial society. The proposed framework and model demonstrates how ALife techniques can be used by researchers in relation to social issues and policies.

  1. Forensic Analysis of Human DNA from Samples Contamined with Bioweapons Agents

    DTIC Science & Technology

    2011-10-01

    Forensic analysis of human DNA from samples contaminated with bioweapons agents Jason Timbers Kathryn Wright Royal Canadian Mounted...Police Forensic Science and Identification Service Prepared By: Royal Canadian Mounted Police RCMP Forensic Science Identification Services... Royal Canadian Mounted Police Forensic Science and Identification Service Prepared By: Royal Canadian Mounted Police RCMP Forensic Science

  2. Fragmentation pathways and structural characterization of organophosphorus compounds related to the Chemical Weapons Convention by electron ionization and electrospray ionization tandem mass spectrometry.

    PubMed

    Hosseini, Seyed Esmaeil; Saeidian, Hamid; Amozadeh, Ali; Naseri, Mohammad Taghi; Babri, Mehran

    2016-12-30

    For unambiguous identification of Chemical Weapons Convention (CWC)-related chemicals in environmental samples, the availability of mass spectra, interpretation skills and rapid microsynthesis of suspected chemicals are essential requirements. For the first time, the electron ionization single quadrupole and electrospray ionization tandem mass spectra of a series of O-alkyl N-[bis(dimethylamino)methylidene]-P-methylphosphonamidates (Scheme 1, cpd 4) were studied for CWC verification purposes. O-Alkyl N-[bis(dimethylamino)methylidene]-P-methylphosphonamidates were prepared through a microsynthetic method and were analyzed using electron ionization and electrospray ionization mass spectrometry with gas and liquid chromatography, respectively, as MS-inlet systems. General EI and ESI fragmentation pathways were proposed and discussed, and collision-induced dissociation studies of the protonated derivatives of these compounds were performed to confirm proposed fragment ion structures by analyzing mass spectra of deuterated analogs. Mass spectrometric studies revealed some interesting fragmentation pathways during the ionization process, such as McLafferty rearrangement, hydrogen rearrangement and a previously unknown intramolecular electrophilic aromatic substitution reaction. The EI and ESI fragmentation routes of the synthesized compounds 4 were investigated with the aim of detecting and identifying CWC-related chemicals during on-site inspection and/or off-site analysis and toxic chemical destruction monitoring. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  3. Relationship between thin-film bond strength as measured by a scratch test, and indentation hardness for bonding agents.

    PubMed

    Kusakabe, Shusuke; Rawls, H Ralph; Hotta, Masato

    2016-03-01

    To evaluate thin-film bond strength between a bonding agent and human dentin, using a scratch test, and the characteristics and accuracy of measurement. One-step bonding agents (BeautiBond; Bond Force; Adper Easy Bond; Clearfil tri-S Bond) and two-step bonding agents (Cleafil SE Bond; FL-Bond II) were investigated in this study. Flat dentin surfaces were prepared for extracted human molars. The dentin surfaces were ground and bonding agents were applied and light cured. The thin-film bond strength test of the specimens was evaluated by the critical load at which the coated bonding agent failed and dentin appeared. The scratch mark sections were then observed under a scanning electron microscope. Indentation hardness was evaluated by the variation in depth under an applied load of 10gf. Data were compared by one-way ANOVA with the Scheffé's post hoc multiple comparison test (p<0.05). In addition, thin-film bond strength and indentation hardness were analyzed using analysis of correlation and covariance. The thin-film bond strength of two-step bonding agents were found to be significantly higher than that of one-step bonding agents with small standard deviations. Scratch marks consistently showed adhesive failure in the vicinity of the bonding agent/dentin interface. The indentation hardness showed a trend that two-step bonding agents have greater hardness than one-step bonding agents. A moderately significant correlation (r(2)=0.31) was found between thin-film bond strength and indentation hardness. Thin-film bond strength test is a valid and reliable means of evaluating bond strength in the vicinity of the adhesive interface and is more accurate than other methods currently in use. Further, the thin-film bond strength is influenced by the hardness of the cued bonding agent. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  4. High reactive sulphide chemically supported on silica surface to prepare functional nanoparticle

    NASA Astrophysics Data System (ADS)

    Chen, Lijuan; Guo, Xiaohui; Jia, Zhixin; Tang, Yuhan; Wu, Lianghui; Luo, Yuanfang; Jia, Demin

    2018-06-01

    A solid-phase preparation method was applied to obtain a novel, green and effective functional nanoparticle, silica-supported sulfur monochloride (silica-s-S2Cl2), by the chemical reaction between chlorine atom and silicon hydroxyl on the silica surface. Through this chemical reaction, silica surface supported with high content of sulfur, and the functional nanoparticles can not only vulcanize the rubber instead of sulfur or other vulcanizing agent with high performance, but also improve the filler-rubber interaction as a modifier due to the improved modification effect. 29Si NMR, Raman spectroscopy, Element analysis and TGA confirm that the sulfur monochloride is chemically bonded on the silica surface. Cure properties measurement, morphology of filler dispersion, mechanical properties measurement, immobilized polymer layer and oxidation induction time increment together show that the novel vulcanizing agent silica-s-S2Cl2 instead of sulfur in rubber vulcanization gives rise to significant improvement in the crosslinking density and the interfacial adhesion between silica particles and the rubber matrix, which is on account of the promoted vulcanizing on the functional silica nanoparticles surface with the supported sulfur.

  5. Peptide-Like Molecules (PLMs): A Journey from Peptide Bond Isosteres to Gramicidin S Mimetics and Mitochondrial Targeting Agents

    PubMed Central

    Wipf, Peter; Xiao, Jingbo; Stephenson, Corey R. J.

    2010-01-01

    Peptides are natural ligands and substrates for receptors and enzymes and exhibit broad physiological effects. However, their use as therapeutic agents often suffers from poor bioavailability and insufficient membrane permeability. The success of peptide mimicry hinges on the ability of bioisosteres, in particular peptide bond replacements, to adopt suitable secondary structures relevant to peptide strands and position functional groups in equivalent space. This perspective highlights past and ongoing studies in our group that involve new methods development as well as specific synthetic library preparations and applications in chemical biology, with the goal to enhance the use of alkene and cyclopropane peptide bond isosteres. PMID:20725595

  6. Hierarchically controlled remote preparation of an arbitrary single-qubit state by using a four-qubit |χ > entangled state

    NASA Astrophysics Data System (ADS)

    Ma, Peng-Cheng; Chen, Gui-Bin; Li, Xiao-Wei; Zhan, You-Bang

    2018-05-01

    In this paper, we present a scheme for Hierarchically controlled remote preparation of an arbitrary single-qubit state via a four-qubit |χ > state as the quantum channel. In this scheme, a sender wishes to help three agents to remotely prepare a quantum state, respectively. The three agents are divided into two grades, that is, an agent is in the upper grade and other two agents are in the lower grade. It is shown that the agent of the upper grade only needs the assistance of any one of the other two agents for recovering the sender's original state, while an agent of the lower grade needs the collaboration of all the other two agents. In other words, the agents of two grades have different authorities to recover sender's original state.

  7. [FEATURES OF MASS-SPECTROMETRIC PROTEIN PROFILES OF STRAINS OF BRUCELLOSIS CAUSATIVE AGENT DURING PREPARATION OF CULTURE ON VARIOUS NUTRIENT MEDIA].

    PubMed

    Ulshina, D V; Kovalev, D A; Zhirov, A M; Zharinova, N V; Khudoleev, A A; Kogotkova, O I; Efremenko, V I; Evchenko, N I; Kulichenko, A N

    2016-01-01

    Carry out comparative analysis using time-of-flight mass-spectrometry with matrix laser desorption/ionization (MALDI-TOF MS) of protein profiles of brucellosis causative agents (Brucella melitensis Rev-1 and Brucella abortus 19BA), cultivated in various nutrient media: Albimi agar, brucellagar and erythrit-agar. Vaccine,strains: Brucella melitensis Rev-1 and Brucella abortus 19BA. Protein profiling in linear mode on Microflex "Bruker Daltonics" MALDI-TOF mass-spectrometer. A number of characteristic features of brucella mass-spectra was detected: in particular, preservation of the total qualitative composition of protein profiles of cultures and significant differences in the intensity of separate peaks depending on the nutrient medium used. Based on the analysis of the data obtained, use of Albimi agar as the nutrient medium for preparation of brucella culture samples for mass-spectrometric analysis was shown to be optimal.

  8. Food and Nutrition: Supplemental Lessons for Training Extension Aides: Food Preparation.

    ERIC Educational Resources Information Center

    Johnson, Evelyn H.; And Others

    The lessons were written to help trainer agents prepare aides for work with families in Extension's Expanded Food and Nutrition Program. The purpose is to enrich the aides' background in food preparation and to provide practical teaching methods that can be used in presenting food preparation information to families. The 21 lessons are an…

  9. Preparation of DPPE-Stabilized Gold Nanoparticles

    ERIC Educational Resources Information Center

    Dungey, Keenan E.; Muller, David P.; Gunter, Tammy

    2005-01-01

    An experiment is presented that introduces students to nanotechnology through the preparation of nanoparticles and their visualization using transmission electron microscopy (TEM). The experiment familiarizes the students with nonaqueous solvents, biphasic reactions, phase-transfer agents, ligands to stabilize growing nanoparticles, and bidentate…

  10. Preparation and characterization of (St-DVB-MAA) ion exchange resins

    NASA Astrophysics Data System (ADS)

    Jiang, Shanquan; Sun, Xiangwei; Ling, Lixing; Wang, Shumin; Wu, Wufeng; Cheng, Shihong; Hu, Yue; Zhong, Chunyan

    2017-08-01

    In this paper, used polyvinyl alcohol as dispersing agent, Benzoyl peroxide as initiator of polymerization, Divinyl benzene as cross-linking agent, Styrene and 2-Methylpropenoic acid as monomer, ion exchange resin (copolymer of St-DVB-MAA)were prepared by suspension polymerization on 80°C. The structures, components and properties of the prepared composite micro gels were characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA). The experiment of ion exchange was conducted by resin to deal with copper ions in the solution. The result showed that performance of the ion exchange capacity was excellent, which impacted by pH.

  11. Reproducible insulin secretion from isolated rat pancreas preparations using an organ bath.

    PubMed

    Morita, Asuka; Ouchi, Motoshi; Terada, Misao; Kon, Hiroe; Kishimoto, Satoko; Satoh, Keitaro; Otani, Naoyuki; Hayashi, Keitaro; Fujita, Tomoe; Inoue, Ken-Ichi; Anzai, Naohiko

    2018-02-09

    Diabetes mellitus is a lifestyle-related disease that is characterized by inappropriate or diminished insulin secretion. Ex vivo pharmacological studies of hypoglycemic agents are often conducted using perfused pancreatic preparations. Pancreas preparations for organ bath experiments do not require cannulation and are therefore less complex than isolated perfused pancreas preparations. However, previous research has generated almost no data on insulin secretion from pancreas preparations using organ bath preparations. The purpose of this study was to investigate the applicability of isolated rat pancreas preparations using the organ bath technique in the quantitative analysis of insulin secretion from β-cells. We found that insulin secretion significantly declined during incubation in the organ bath, whereas it was maintained in the presence of 1 µM GLP-1. Conversely, amylase secretion exhibited a modest increase during incubation and was not altered in the presence of GLP-1. These results demonstrate that the pancreatic organ bath preparation is a sensitive and reproducible method for the ex vivo assessment of the pharmacological properties of hypoglycemic agents.

  12. Preparation and Physiological activities of sulphated derivative extracted from corn bran

    NASA Astrophysics Data System (ADS)

    Mo, Qing; Dai, Linghao; Ma, Jianjun; Zhao, Xiaojing; Zhu, Linghui

    2017-05-01

    In the present study, the sulphated derivative (S-CBP) with the degree of substitution (0.46) was successfully prepared from the polysaccharide extracted from corn bran. Compared with native polysaccharide, the structures of the sulphated derivative were confirmed by FT-IR and SEC-LLS and the molecular weight were changed by chemical modification. Sulfation enhanced the antioxidant activities in a dose-dependent way, which seemed to be dependent on the character of the substituted group. The results suggest that the sulphated derivative, extracted from corn bran, are potential natural antioxidant and blood fat reduce agent.

  13. U.S. Policy and the Uncertain State of Military Usage of Riot Control Agents.

    DTIC Science & Technology

    1998-04-30

    capsicum, a naturally occurring oily resin found in the cayenne pepper . Known as pepper spray or OC, it is different from CS, 23 CN, and other RCA...Non-Lethals 7 Riot Control Agents 11 The U.S. Army and CS 13 The RCA Policy Debate: Seventy Years of Uncertainty 15 Non-Chemical Pepper Spray: A...of the crowd to use their recently-issued pepper spray, but two soldiers were quickly injured by flying debris. The mob seemed

  14. Pomalidomide desensitization in a patient hypersensitive to immunomodulating agents

    PubMed Central

    Seki, J.T.; Sakurai, N.; Lam, W.; Reece, D.E.

    2017-01-01

    Despite progressive treatments with tandem stem-cell transplantation, patients with incurable myeloma eventually succumb to relapsed or refractory disease if left untreated. Promising agents such as proteasome inhibitors and immunomodulating imide drugs (imids), including the newer-generation agent pomalidomide, in combination with lower-dose dexamethasone, have been shown to be effective and to significantly improve and prolong survival in pretreated patients. Although the incidence of pomalidomide hypersensitivity reaction (hsr) in this class of drugs is not as well known, we have documented cutaneous toxicity (grade 3 by the Common Terminology Criteria for Adverse Events, version 4) in 2 separate cases (not yet published). Because the imids are chemically, structurally, and pharmacologically similar, it is not unreasonable to consider possible cross-reactivity in pomalidomide recipients who developed hsr when receiving previous lines of imids. As a patient’s advocate, it is only prudent to provide a responsible, and yet practical, means to better address cross-sensitivity for patients. Intervention with the use of a rapid desensitization program (rdp) as a preventive measure should be introduced before initiating pomalidomide. Such a proactive measure for the patient’s safety will ensure a smooth transition into pomalidomide treatment. A hsr can be either related or non-related to immunoglobulin E. As imids become an essential treatment backbone for myeloma and other plasma-cell diseases, an increasing number of patients could experience skin and other life-threatening toxicities, resulting in unnecessary discontinuation of these life-prolonging agents. An extemporaneously prepared pomalidomide suspension developed at our centre enables patients to undergo rdp safely. Patients enjoy a good quality of life and clinical response after the rdp procedure. PMID:28874903

  15. CdSe/AsS core-shell quantum dots: preparation and two-photon fluorescence.

    PubMed

    Wang, Junzhong; Lin, Ming; Yan, Yongli; Wang, Zhe; Ho, Paul C; Loh, Kian Ping

    2009-08-19

    Arsenic(II) sulfide (AsS)-coated CdSe core-shell nanocrystals can be prepared by a cluster-complex deposition approach under mild conditions. At 60 degrees C, growth of an AsS shell onto a CdSe nanocrystal can be realized through the crystallization of a cluster complex of AsS/butylamine in a mixed solvent of isopropanol/chloroform. The new, type I core-shell nanocrystal exhibits markedly enhanced one-photon fluorescence as well two-photon upconversion fluorescence. The nanocrystals can be used for infrared-excited upconversion cellular labeling.

  16. Performance Evaluation and Adaptability Research of Flowing Gel System Prepared with Re-injected Waste Water

    NASA Astrophysics Data System (ADS)

    Shi, Lei; You, Jing; Liu, Na; Liu, Xinmin; Wang, Zhiqiang; Zhang, Tiantian; Gu, Yi; Guo, Suzhen; Gao, Shanshan

    2017-12-01

    The crosslinking intensity and stability of flowing gel system prepared with re-injected waste water are seriously affected as the high salinity waste water contains a high concentration of Na+, Fe2+, S2-, Ca2+, etc. The influence of various ions on the flowing gel system can be reduced by increasing polymer concentration, adding new ferric ion stabilizing agent (MQ) and calcium ion eliminating agent (CW). The technique of profile controlling and oil-displacing is carried out in Chanan multi-purpose station, Chabei multi-purpose station and Chayi multi-purpose station of Huabei Oilfield. The flowing gel system is injected from 10 downflow wells and the 15 offsetting production wells have increased the yield by 1770 tons.

  17. Chemical agents for the control of plaque and plaque microflora: an overview.

    PubMed

    Gaffar, A; Afflitto, J; Nabi, N

    1997-10-01

    This presentation provides an overview of the technologies available for the chemical control of plaque. It is generally accepted that the formation of dental plaque at the interfaces of tooth/gingiva is one of the major causes of gingival inflammation and dental caries. Several therapeutic approaches have been used to control dental plaque and supragingival infections. These include fluoride preparations such as stannous fluoride, oxygenating agents, anti-attachment agents, and cationic and non-cationic antibacterial agents. Among the fluoride preparations, stable stannous fluoride pastes and gels have been shown to reduce supragingival plaque, gingivitis, hypersensitivity and caries. The effect of the oxygenating agents on the supragingival plaque has been equivocal, but recent data indicate that a stable agent which provides sustained active oxygen release is effective in controlling plaque. A polymer, PVPA, which reduced attachment of bacteria to teeth was shown to significantly reduce plaque formation in humans. A new generation of antibacterials includes non-ionics such as triclosan, which in combination with a special polymer delivery system, has been shown to reduce plaque, gingivitis, supragingival calculus and dental caries in long-term studies conducted around the world. Unlike the first generation of agents, the triclosan/copolymer/sodium fluoride system is effective in long-term clinicals and does not cause staining of teeth, increase in calculus, or disturbance in the oral microbial ecology.

  18. Reducing agent-free synthesis of curcumin-loaded albumin nanoparticles by self-assembly at room temperature.

    PubMed

    Safavi, Maryam Sadat; Shojaosadati, Seyed Abbas; Yang, Hye Gyeong; Kim, Yejin; Park, Eun Ji; Lee, Kang Choon; Na, Dong Hee

    2017-08-30

    The purpose of this study was to prepare curcumin-loaded bovine serum albumin nanoparticles (CCM-BSA-NPs) by reducing agent-free self-assembly at room temperature. A 2 4 factorial design approach was used to investigate the CCM-BSA-NP preparation process at different pH values, temperatures, dithiothreitol amounts, and CCM/BSA mass ratios. Increasing the ionic strength enabled preparation of CCM-BSA-NPs at 25°C without reducing agent. CCM-BSA-NPs prepared under the optimized conditions at 25°C showed a particle size of 110±6nm, yield of 88.5%, and drug loading of 7.1%. The CCM-BSA-NPs showed strong antioxidant activity and neuroprotective effects in glutamate-induced mouse hippocampal neuronal HT22 cells. This study suggests that ionic strength can be a key parameter affecting the preparation of albumin-based NPs. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. [Preparation and spectral characterization of CdS(y)Te(1-y) thin films].

    PubMed

    Li, Wei; Feng, Liang-Huan; Wu, Li-Li; Zhang, Jing-Quan; Li, Bing; Lei, Zhi; Cai, Ya-Ping; Zheng, Jia-Gui; Cai, Wei; Zhang, Dong-Min

    2008-03-01

    CdS(y)Te(1-y) (0 < or = y < or = 1) polycrystalline thin films were prepared on glass substrates by co-evaporation of powders of CdTe and CdS. For the characterization of the structure and composition of the CdS(y)Te(1-y) thin films the X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) were used. The results indicate that the values of sulfur content y detected and controlled by the quartz wafer detector show good agreement with the EDS results. The films were found to be cubic for x < 0. 3, and hexagonal for x > or = 0.3. The 20-50 nm of grain sizes for CdS(y)Te(1-y) thin films were calculated using a method of XRD analysis. Finally, the optical properties of CdS(y)Te(1-y) thin films were characterized by UV-Vis-NIR spectroscopy alone. According to a method from Swanepoel, together with the first-order Sellmeier model, the thickness, of d-535 nm, energy gap of E(g)-1.41 eV, absorption coefficient, alpha(lambda) and refractive index, n(lambda) of CdS(0.22) Te(0.78) thin films were determined from the transmittance at normal incidence of light in the wavelength range 300-2 500 nm. The results also indicate that the CdS(y)Te(1-y) thin films with any composition (0 < or = y < or = 1) can be prepared by co-evaporation, and the method to characterize the optical properties of CdS(y)Te(1-y) thin films can be implemented for other semiconductor thin films.

  20. Strategies for the preparation of bifunctional gadolinium(III) chelators

    PubMed Central

    Frullano, Luca; Caravan, Peter

    2012-01-01

    The development of gadolinium chelators that can be easily and readily linked to various substrates is of primary importance for the development high relaxation efficiency and/or targeted magnetic resonance imaging (MRI) contrast agents. Over the last 25 years a large number of bifunctional chelators have been prepared. For the most part, these compounds are based on ligands that are already used in clinically approved contrast agents. More recently, new bifunctional chelators have been reported based on complexes that show a more potent relaxation effect, faster complexation kinetics and in some cases simpler synthetic procedures. This review provides an overview of the synthetic strategies used for the preparation of bifunctional chelators for MRI applications. PMID:22375102

  1. TRICARE; TRICARE sanction authority for third-party billing agents. Final rule.

    PubMed

    2013-02-26

    This final rule will provide the Director, TRICARE Management Activity (TMA), or designee, with the authority to sanction third-party billing agents by invoking the administrative remedy of exclusion or suspension from the TRICARE program. Such sanctions may be invoked in situations involving fraud or abuse on the part of third-party billing agents that prepare or submit claims presented to TRICARE for payment.

  2. Preparation of AgInS2 quantum dot/In2S3 co-sensitized photoelectrodes by a facile aqueous-phase synthesis route and their photovoltaic performance

    NASA Astrophysics Data System (ADS)

    Wang, Yuanqiang; Zhang, Qinghong; Li, Yaogang; Wang, Hongzhi

    2015-03-01

    In an aqueous-phase system, AgInS2 quantum dot (QD) sensitized TiO2 photoanodes were prepared in situ by the reaction of β-In2S3 nanocrystals and as-prepared TiO2/Ag2S-QD electrodes, followed by a covering process with a ZnS passivation layer. A facile successive ionic layer adsorption and reaction (SILAR) method was adopted to obtain TiO2/Ag2S-QD electrodes. β-In2S3 nanocrystals synthesized by the chemical bath deposition (CBD) process serve as the reactant of AgInS2 as well as a buffer layer between the interfaces of TiO2 and AgInS2-QDs. A polysulfide electrolyte and a Pt-coated FTO glass count electrode were used to test the photovoltaic performance of the constructed devices. The characteristics of the sensitized photoelectrodes were studied in more detail by electron microscopy, X-ray techniques, and optical and photoelectric performance measurements. AgInS2 is the main photo-sensitizer for TiO2/AgInS2-QD/In2S3 electrodes and excess In2S3 appears on the surface of the electrodes. Based on the optimal Ag2S SILAR cycle, the best photovoltaic performance of the prepared TiO2/AgInS2-QD/In2S3 electrode with the short-circuit photocurrent density (Jsc) of 7.87 mA cm-2 and power conversion efficiency (η) of 0.70% under full one-sun illumination was achieved.In an aqueous-phase system, AgInS2 quantum dot (QD) sensitized TiO2 photoanodes were prepared in situ by the reaction of β-In2S3 nanocrystals and as-prepared TiO2/Ag2S-QD electrodes, followed by a covering process with a ZnS passivation layer. A facile successive ionic layer adsorption and reaction (SILAR) method was adopted to obtain TiO2/Ag2S-QD electrodes. β-In2S3 nanocrystals synthesized by the chemical bath deposition (CBD) process serve as the reactant of AgInS2 as well as a buffer layer between the interfaces of TiO2 and AgInS2-QDs. A polysulfide electrolyte and a Pt-coated FTO glass count electrode were used to test the photovoltaic performance of the constructed devices. The characteristics of the

  3. Analysis of Nerve Agent Metabolites from Hair for Long-Term Verification of Nerve Agent Exposure

    DTIC Science & Technology

    2016-05-09

    Analysis of Nerve Agent Metabolites from Hair for Long-Term Verification of Nerve Agent Exposure Amanda S. Appel,† John H. McDonough,‡ Joseph D...feasible. In this study, hair was evaluated as a long-term repository of nerve agent hydrolysis products. Pinacolyl methylphosphonic acid (PMPA...hydrolysis product of soman) and isopropyl methylphosphonic acid (IMPA; hydrolysis product of sarin) were extracted from hair samples with N,N

  4. A simple structure of Cu2ZnSnS4/CdS solar cells prepared by sputtering

    NASA Astrophysics Data System (ADS)

    Li, Zhishan; Wang, Shurong; Ma, Xun; Yang, Min; Jiang, Zhi; Liu, Tao; Lu, Yilei; Liu, Sijia

    2017-12-01

    In this work, Cu2ZnSnS4 (CZTS) thin films were grown on Mo-coated Soda-lime-glass (SLG) substrates by annealing of sputtered ZnS/Sn/CuS precursors at 580 ℃ for 15 min. As a try, the CZTS solar cells were fabricated using simple structure of Mo-coated SLG/CZTS/CdS/Al and traditional structure of Mo-coated SLG/CZTS/CdS/i-ZnO/In2O3:SnO2 (ITO)/Al, respectively. The results show that the CZTS device with simple structure can achieve same level of the open circuit voltage (Voc) compared with that of traditional structure. In addition, the power conversion efficiency of 2.95% and 3.59% were obtained with simple structure and traditional structure, respectively. The CZTS solar cell with simple structure provides a promising way and an easy process to prepare high-performance CZTS thin film solar cells which is available to large-scale industrial production in the future.

  5. Interaction of insulin with colloidal ZnS quantum dots functionalized by various surface capping agents.

    PubMed

    Hosseinzadeh, Ghader; Maghari, Ali; Farniya, Seyed Morteza Famil; Keihan, Amir Homayoun; Moosavi-Movahedi, Ali A

    2017-08-01

    Interaction of quantum dots (QDs) and proteins strongly influenced by the surface characteristics of the QDs at the protein-QD interface. For a precise control of these surface-related interactions, it is necessary to improve our understanding in this field. In this regard, in the present work, the interaction between the insulin and differently functionalized ZnS quantum dots (QDs) were studied. The ZnS QDs were functionalized with various functional groups of hydroxyl (OH), carboxyl (COOH), amine (NH 2 ), and amino acid (COOH and NH 2 ). The effect of surface hydrophobicity was also studied by changing the alkyl-chain lengths of mercaptocarboxylic acid capping agents. The interaction between insulin and the ZnS QDs were investigated by fluorescence quenching, synchronous fluorescence, circular dichroism (CD), and thermal aggregation techniques. The results reveal that among the studied QDs, mercaptosuccinic acid functionalized QDs has the strongest interaction (∆G ° =-51.50kJ/mol at 310K) with insulin, mercaptoethanol functionalized QDs destabilize insulin by increasing the beta-sheet contents, and only cysteine functionalized QDs improves the insulin stability by increasing the alpha-helix contents of the protein, and. Our results also indicate that by increasing the alkyl-chain length of capping agents, due to an increase in hydrophobicity of the QDs surface, the beta-sheet contents of insulin increase which results in the enhancement of insulin instability. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Preparation and Pharmacokinetics Evaluation of Solid Self-Microemulsifying Drug Delivery System (S-SMEDDS) of Osthole.

    PubMed

    Sun, Chaojie; Gui, Yun; Hu, Rongfeng; Chen, Jiayi; Wang, Bin; Guo, Yuxing; Lu, Wenjie; Nie, Xiangjiang; Shen, Qiang; Gao, Song; Fang, Wenyou

    2018-05-29

    The study was performed aiming to enhance the solubility and oral bioavailability of poorly water-soluble drug osthole by formulating solid self-microemulsifying drug delivery system (S-SMEDDS) via spherical crystallization technique. Firstly, the liquid self-microemulsifying drug delivery system (L-SMEDDS) of osthole was formulated with castor oil, Cremophor RH40, and 1,2-propylene glycol after screening various lipids and emulsifiers. The type and amount of polymeric materials, good solvents, bridging agents, and poor solvents in S-SMEDDS formulations were further determined by single-factor study. The optimal formulation contained 1:2 of ethyl cellulose (EC) and Eudragit S100, which served as matrix forming and enteric coating polymers respectively. Anhydrous ethanol and dichloromethane with a ratio of 5:3 are required to perform as good solvent and bridging agent, respectively, with the addition of 0.08% SDS aqueous solution as poor solvent. The optimized osthole S-SMEDDS had a high yield (83.91 ± 3.31%) and encapsulation efficiency (78.39 ± 2.25%). Secondly, osthole L-SMEDDS was solidified to osthole S-SMEDDS with no significant changes in terms of morphology, particle size, and zeta potential. In vitro release study demonstrated a sustained release of the drug from osthole S-SMEDDS. Moreover, in vivo pharmacokinetic study showed that the T max and mean residence time (MRT (0-t) ) of osthole were significantly prolonged and further confirmed that osthole S-SMEDDS exhibited sustained release effect in rabbits. Comparing with osthole aqueous suspension and L-SMEDDS, osthole S-SMEDDS increased bioavailability by 205 and 152%, respectively. The results suggested that S-SMEDDS was an effective oral solid dosage form, which can improve the solubility and oral bioavailability of poorly water-soluble drug osthole.

  7. Luminescence characteristics of impurities-activated ZnS nanocrystals prepared in microemulsion with hydrothermal treatment

    NASA Astrophysics Data System (ADS)

    Xu, S. J.; Chua, S. J.; Liu, B.; Gan, L. M.; Chew, C. H.; Xu, G. Q.

    1998-07-01

    Cu-, Eu-, or Mn-doped ZnS nanocrystalline phosphors were prepared at room temperature using a chemical synthesis method. Transmission electron microscopy observation shows that the size of the ZnS clusters is in the 3-18 nm range. New luminescence characteristics such as strong and stable visible-light emissions with different colors were observed from the doped ZnS nanocrystals at room temperature. These results strongly suggest that impurities, especially transition metals and rare-earth metals-activated ZnS nanoclusters form a new class of luminescent materials.

  8. Preparation of ZnS/ZnO core - Shell nanocomposite and its photocatalytic behaviour for dye degradation

    NASA Astrophysics Data System (ADS)

    Patil, Bharati N.; Acharya, Smita A.

    2018-05-01

    In the present work ZnS-ZnO core-shell-type composite nanostructures was prepared by hydrothermal method. The prepared samples were characterized by X-ray diffraction (XRD) for structural confirmation. Microstructural study by scanning electron microscopy (SEM) exhibit nanoscale dimensions of as-synthesized composite. UV/VIS spectra were recorded for evaluation of photophysical properties. The composite was explored as photocatalysts to study dye degradation using methylene blue in aqueous slurry under irradiation of 663 nm wavelength and congo red under irradiation of 493 nm wavelength. Under the same conditions the photocatalytic activity of the individual phases ZnS and ZnO were also examined, just for sake of comparison. The ZnS-ZnO composite is found to be enhancing the rate of photo degradation of toxic dyes in presence of visible light as compared to ZnS and ZnO individual phases. Thus ZnS based metal sulphide/oxide semiconductor nanocomposites are potential material for Photo-degradation of toxic dyes, and act as good photocatalyst.

  9. The effect of temperature and addition of reducing agent on sodium stannate preparation from cassiterite by the alkaline roasting process

    NASA Astrophysics Data System (ADS)

    Lalasari, Latifa Hanum; Andriyah, Lia; Arini, Tri; Firdiyono, F.

    2018-04-01

    Sodium stannate is an intermediate compound with the formula Na2SnO3. This compound is easily dissolved in water and has many applications in the electroplating industry, tin alloy production, and catalysts for organic synthesis. In this occasion was investigated the effect of temperature and the addition of reducing agent on making of sodium stannate phase from cassiterite by an alkaline roasting process using sodium carbonate (Na2CO3). Firstly, cassiterite was roasted at 700 °C for 3 hours and continued leaching process using 10% HCl solution at 110 °C for 2 hours. The cassiterite residue than was dried at 110 °C and mixed homogenously with a Na2CO3 decomposer at a mass ratio Na2CO3/cassiterite as 5:3 for the decomposition process. It was done by variation temperatures (300 °C, 700 °C, 800 °C, 870 °C, 900 °C) for 3 hours, variation times (3, 4, 5 hours) at a roasting temperature of 700 °C and addition of reducing agent such as sub-bituminous coal. The result of the experiment shows that cassiterite prepared by roasting and acid leaching process has the chemical composition as follows: 59.98% Sn, 22.58% O, 3.20% Ce, 3.15% La, 2.57% Nd, 1.67% Ti, 1.56% Fe, 1.24% P, 0.62% Ca and others. The Na2SnO3 phase begins to form at a roasting temperature of 870 °C for 3 hours. Although the roasting times was extended from 3 hours to 5 hours at 700 °C, the Na2SnO3 phase also has not yet formed. In other conditions, the addition of coal reducing agent to the roasting process would cause formations of Sn metal besides Na2SnO3 phase at 870 °C. At temperatures lower than 870 °C, the addition of coal only forms Sn metal, whereas the sodium stannate phase is not formed.

  10. Aqueous synthesis of highly luminescent AgInS2-ZnS quantum dots and their biological applications

    NASA Astrophysics Data System (ADS)

    Regulacio, Michelle D.; Win, Khin Yin; Lo, Seong Loong; Zhang, Shuang-Yuan; Zhang, Xinhai; Wang, Shu; Han, Ming-Yong; Zheng, Yuangang

    2013-02-01

    Highly emissive and air-stable AgInS2-ZnS quantum dots (ZAIS QDs) with quantum yields of up to 20% have been successfully synthesized directly in aqueous media in the presence of polyacrylic acid (PAA) and mercaptoacetic acid (MAA) as stabilizing and reactivity-controlling agents. The as-prepared water-dispersible ZAIS QDs are around 3 nm in size, possess the tetragonal chalcopyrite crystal structure, and exhibit long fluorescence lifetimes (>100 ns). In addition, these ZAIS QDs are found to exhibit excellent optical and colloidal stability in physiologically relevant pH values as well as very low cytotoxicity, which render them particularly suitable for biological applications. Their potential use in biological labelling of baculoviral vectors is demonstrated.Highly emissive and air-stable AgInS2-ZnS quantum dots (ZAIS QDs) with quantum yields of up to 20% have been successfully synthesized directly in aqueous media in the presence of polyacrylic acid (PAA) and mercaptoacetic acid (MAA) as stabilizing and reactivity-controlling agents. The as-prepared water-dispersible ZAIS QDs are around 3 nm in size, possess the tetragonal chalcopyrite crystal structure, and exhibit long fluorescence lifetimes (>100 ns). In addition, these ZAIS QDs are found to exhibit excellent optical and colloidal stability in physiologically relevant pH values as well as very low cytotoxicity, which render them particularly suitable for biological applications. Their potential use in biological labelling of baculoviral vectors is demonstrated. Electronic supplementary information (ESI) available: Quantum yields, EDX spectrum and photoluminescence decay curves. See DOI: 10.1039/c3nr34159c

  11. Automated Agent Ontology Creation for Distributed Databases

    DTIC Science & Technology

    2004-03-01

    relationships between themselves if one exists. For example, if one agent’s ontology was ‘ NBA ’ and the second agent’s ontology was ‘College Hoops...the two agents should discover their relationship ‘ basketball ’ [28]. The authors’ agents use supervised inductive learning to learn their individual

  12. Operation of the Chemical Agent Munitions Disposal System (CAMDS) at Tooele Army Depot, Utah.

    DTIC Science & Technology

    1978-09-01

    parts furnace where the container is opened to expose the agent; the agent is boiled out and burned ; and the residual container is heat treated for...fuze booster to expose the booster pellet so it will burn instead of detonate in the Deactivation Furnace. A portion of the solution in the coolant...demilitarization equipment exposed to agent GB will be chemically decontaminated to prepare for operations with burstered mustard projectiles. The

  13. The Preparation of Master's-Level Professional Counselors for Positions in College and University Counseling Centers

    ERIC Educational Resources Information Center

    Shaw, Brian M.; Remley, Theodore P., Jr.; Ward, Christine

    2014-01-01

    This study investigated college and university counseling center directors' perceptions of the adequacy of the preparation of master's-level counselors for work in college and university counseling centers. Results indicated that counselors were rated on average as prepared; however, many directors had concerns about counselors'…

  14. Response surface method (RSM) for optimization of ionic conductivity of membranes polymer electrolyte poly (vinylidene fluoride) (PVDF) with polyvinyl pyrrolidone (PVP) as pore forming agent

    NASA Astrophysics Data System (ADS)

    Dyartanti, E. R.; Susanto, H.; Widiasa, I. N.; Purwanto, A.

    2017-06-01

    The Membranes Polymer Gel Electrolyte (MPGEs) based poly (vinylidene fluoride) (PVDF) was prepared by a phase inversion method using polyvinyl pyrrolidone (PVP) as a pore-forming agent and N, N-dimethyl acetamide (DMAc) as a solvent and water as non solvet. The membranes were then soaked in 1 M lithium hexafluorophosphate (LiPF6) in ethylene carbonate (EC) / dimethyl carbonate (DMC) / Diethyl carbonate (DEC) (4:2:4 %vol) solution in order to prepare polymer electrolyte membranes. The MPEGs PVDF/PVP/Nanoclay was applied using central composite design (CCD) experimental design to obtain a quantitative relationship between selected membranes prepared parameters namely (PVDF, PVP as pore forming agent and nanoclay filler concentration) and Ionic conductivity MPEGs. The model was used to find the optimum ionic conductivity from polymer electrolyte membranes. The polymer electrolyte membranes show good ionic conductivity on the order of 6.3 - 8.7 x 10-3 S cm-1 at the ambient temperatures. The ionic conductivity tended to increase with PVP and nanoclay concentration and decrease with PVDF composition. The model predicted the maximum ionic conductivity of 8.47 x 10-3 S cm-1 when the PVDF, PVP and nanoclay concentration were set at 8.01 %, 8.04 % and 10.12%, respectively. The first section in your paper.

  15. Fate of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX) on soil following accelerant-based fire and liquid decontamination.

    PubMed

    Gravett, M R; Hopkins, F B; Self, A J; Webb, A J; Timperley, C M; Riches, J R

    2014-08-01

    In the event of alleged use of organophosphorus nerve agents, all kinds of environmental samples can be received for analysis. These might include decontaminated and charred matter collected from the site of a suspected chemical attack. In other scenarios, such matter might be sampled to confirm the site of a chemical weapon test or clandestine laboratory decontaminated and burned to prevent discovery. To provide an analytical capability for these contingencies, we present a preliminary investigation of the effect of accelerant-based fire and liquid decontamination on soil contaminated with the nerve agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX). The objectives were (a) to determine if VX or its degradation products were detectable in soil after an accelerant-based fire promoted by aviation fuel, including following decontamination with Decontamination Solution 2 (DS2) or aqueous sodium hypochlorite, (b) to develop analytical methods to support forensic analysis of accelerant-soaked, decontaminated and charred soil and (c) to inform the design of future experiments of this type to improve analytical fidelity. Our results show for the first time that modern analytical techniques can be used to identify residual VX and its degradation products in contaminated soil after an accelerant-based fire and after chemical decontamination and then fire. Comparison of the gas chromatography-mass spectrometry (GC-MS) profiles of VX and its impurities/degradation products from contaminated burnt soil, and burnt soil spiked with VX, indicated that the fire resulted in the production of diethyl methylphosphonate and O,S-diethyl methylphosphonothiolate (by an unknown mechanism). Other products identified were indicative of chemical decontamination, and some of these provided evidence of the decontaminant used, for example, ethyl 2-methoxyethyl methylphosphonate and bis(2-methoxyethyl) methylphosphonate following decontamination with DS2. Sample preparation

  16. Guidelines for preparing a quality assurance plan for district offices of the U.S. Geological Survey

    USGS Publications Warehouse

    Schroder, L.J.; Shampine, W.J.

    1992-01-01

    The U.S. Geological Survey has a policy that requires each District office to prepare a Quality Assurance Plan. This plan is a combination of a District's management principles and quality assurance processes. The guidelines presented in this report provide a framework or expanded outline that a District can use to prepare a plan. Parti- cular emphasis is given to a District's: (1) quality assurance policies; (2) organization and staff responsibilities; and (3) program and project planning. The guidelines address the 'how', 'what', and 'who' questions that need to be answered when a District Quality Assurance Plan is prepared.

  17. Chemical Agents: Facts about Evacuation

    MedlinePlus

    ... Resources for Emergency Health Professionals Training & Education Social Media What’s New Preparation & Planning More on Preparedness What CDC is ... Resources for Emergency Health Professionals Training & Education Social Media What’s New Preparation & Planning More on Preparedness What CDC is ...

  18. Cu(In,Ga)S2, Thin-Film Solar Cells Prepared by H2S Sulfurization of CuGa-In Precursor

    NASA Technical Reports Server (NTRS)

    Dhere, Neelkanth G.; Kulkarni, Shashank R.; Chavan, Sanjay S.; Ghongadi, Shantinath R.

    2005-01-01

    Thin-film CuInS2 solar cell is the leading candidate for space power because of bandgap near the optimum value for AM0 solar radiation outside the earth's atmosphere, excellent radiation hardness, and freedom from intrinsic degradation mechanisms unlike a-Si:H cells. Ultra-lightweight thin-film solar cells deposited on flexible polyimide plastic substrates such as Kapton(trademark), Upilex(trademark), and Apical(trademark) have a potential for achieving specific power of 1000 W/kg, while the state-of-art specific power of the present day solar cells is 66 W/kg. This paper describes the preparation of Cu-rich CuIn(sub 1-x)Ga(sub x)S(sub 2) (CIGS2) thin films and solar cells by a process of sulfurization of CuGa-In precursor similar to that being used for preparation of large-compact-grain CuIn(sub 1-x)Ga(sub x)Se2 thin films and efficient solar cells at FSEC PV Materials Lab.

  19. Optimal Bowel Preparation for Video Capsule Endoscopy

    PubMed Central

    Song, Hyun Joo; Moon, Jeong Seop; Shim, Ki-Nam

    2016-01-01

    During video capsule endoscopy (VCE), several factors, such as air bubbles, food material in the small bowel, and delayed gastric and small bowel transit time, influence diagnostic yield, small bowel visualization quality, and cecal completion rate. Therefore, bowel preparation before VCE is as essential as bowel preparation before colonoscopy. To date, there have been many comparative studies, consensus, and guidelines regarding different kinds of bowel cleansing agents in bowel preparation for small bowel VCE. Presently, polyethylene glycol- (PEG-) based regimens are given primary recommendation. Sodium picosulphate-based regimens are secondarily recommended, as their cleansing efficacy is less than that of PEG-based regimens. Sodium phosphate as well as complementary simethicone and prokinetics use are considered. In this paper, we reviewed previous studies regarding bowel preparation for small bowel VCE and suggested optimal bowel preparation of VCE. PMID:26880894

  20. Feasibility of adjuvant chemotherapy with S-1 plus carboplatin followed by single-agent maintenance therapy with S-1 for completely resected non-small-cell lung cancer: results of the Setouchi Lung Cancer Group Study 1001.

    PubMed

    Okumura, Norihito; Sonobe, Makoto; Okabe, Kazunori; Nakamura, Hiroshige; Kataoka, Masafumi; Yamashita, Motohiro; Nakata, Masao; Kataoka, Kazuhiko; Yamashita, Yoshinori; Soh, Junichi; Yoshioka, Hiroshige; Hotta, Katsuyuki; Matsuo, Keitaro; Sakamoto, Junichi; Toyooka, Shinichi; Date, Hiroshi

    2017-04-01

    This multicenter study evaluated the feasibility of novel adjuvant chemotherapy with S-1 plus carboplatin followed by single-agent, long-term maintenance with S-1 in patients with completely resected stage II-IIIA non-small-cell lung cancer (NSCLC). Patients received four cycles of S-1 (80 mg/m 2 /day for 2 weeks, followed by 2 weeks rest) plus carboplatin (area under the curve 5, day 1) followed by S-1 (80 mg/m 2 /day for 2 weeks, followed by a 1-week rest). Patients unable to continue S-1 plus carboplatin because of severe toxicity converted to single-agent S-1 maintenance. The duration of adjuvant chemotherapy was 10 months in both situations. The primary endpoint was feasibility, defined as the proportion of patients who completed four cycles of S-1 plus carboplatin and single-agent S-1 maintenance for 10 months. The treatment completion rate was determined; treatment was considered feasible if the lower 90% confidence interval (CI) was ≥50%. Eighty-nine patients were enrolled, of whom 87 were eligible and assessable. Seventy-eight patients (89.7%) completed four cycles of S-1 plus carboplatin and 55 (63.2%) completed the following S-1 maintenance therapy for a total of 10 months. The treatment completion rate was 63.2% (90% CI, 54.4-71.2%), indicating feasibility. There were no treatment-related deaths. Grade 3/4 toxicities included neutropenia (13.8%), thrombocytopenia (11.5%), and anorexia (4.6%). The 2-year relapse-free survival rate was 59.8%. We concluded that adjuvant chemotherapy with S-1 plus carboplatin followed by single-agent maintenance therapy with S-1 is feasible and tolerable in patients with completely resected NSCLC. UMIN000005041.

  1. Mental and Active Preparation: Examining Variations in Women's Processes of Preparing to Leave Abusive Relationships.

    PubMed

    Bermea, Autumn M; Khaw, Lyndal; Hardesty, Jennifer L; Rosenbloom, Lindsay; Salerno, Craig

    2017-02-01

    Although the process of leaving abusive relationships has received increased research attention, preparing to leave is still largely understudied. Despite an emphasis on safety planning, not all women take active steps to prepare, and the characteristics and experiences of those who do or do not actively prepare are unknown. We address this gap with a secondary data analysis of interviews with 25 abused mothers in the process of leaving. All women initially engaged in mental planning, where they had emotionally disconnected from their partners. Using constructivist grounded theory techniques, we identified two distinct groups: those whose mental planning led to active planning ( n = 11), and those who moved directly from mental planning to leaving ( n = 14) with little time or need to actively plan. The groups differed on several individual, relationship, and child factors, which may have impacted the ability or decisions to prepare. This study supports the feminist view that survivors are not helpless victims but active agents who strategize for safety. Those who engage solely in mental planning still prepare to leave, even if they do not engage in active planning. Practitioners should consider factors affecting preparations and acknowledge mental planning as a necessary effort in leaving.

  2. Aqueous phase preparation of ultrasmall MoSe2 nanodots for efficient photothermal therapy of cancer cells

    NASA Astrophysics Data System (ADS)

    Yuwen, Lihui; Zhou, Jiajia; Zhang, Yuqian; Zhang, Qi; Shan, Jingyang; Luo, Zhimin; Weng, Lixing; Teng, Zhaogang; Wang, Lianhui

    2016-01-01

    Photothermal therapy (PTT) is a promising cancer treatment with both high effectiveness and fewer side effects. However, an ideal PTT agent not only needs strong absorption of near-infrared (NIR) light and high photothermal conversion efficiency, but also needs good biocompatibility, stability, and small size, which makes the design and preparation of a novel PTT agent a great challenge. In this work, we developed an ultrasonication-assisted liquid exfoliation method for the direct preparation of ultrasmall (2-3 nm) MoSe2 nanodots (NDs) in aqueous solution and demonstrated their superior properties as a PTT agent. The as-prepared MoSe2 NDs have strong absorption of NIR light and high photothermal conversion efficiency of about 46.5%. In vitro cellular experiments demonstrate that MoSe2 NDs have negligible cytotoxicity and can efficiently kill HeLa cells (human cervical cell line) under NIR laser (785 nm) irradiation.Photothermal therapy (PTT) is a promising cancer treatment with both high effectiveness and fewer side effects. However, an ideal PTT agent not only needs strong absorption of near-infrared (NIR) light and high photothermal conversion efficiency, but also needs good biocompatibility, stability, and small size, which makes the design and preparation of a novel PTT agent a great challenge. In this work, we developed an ultrasonication-assisted liquid exfoliation method for the direct preparation of ultrasmall (2-3 nm) MoSe2 nanodots (NDs) in aqueous solution and demonstrated their superior properties as a PTT agent. The as-prepared MoSe2 NDs have strong absorption of NIR light and high photothermal conversion efficiency of about 46.5%. In vitro cellular experiments demonstrate that MoSe2 NDs have negligible cytotoxicity and can efficiently kill HeLa cells (human cervical cell line) under NIR laser (785 nm) irradiation. Electronic supplementary information (ESI) available: Characterization, size distribution and EDS spectrum of MoSe2 NDs, calculation of

  3. Glide path preparation in S-shaped canals with rotary pathfinding nickel-titanium instruments.

    PubMed

    Ajuz, Natasha C C; Armada, Luciana; Gonçalves, Lucio S; Debelian, Gilberto; Siqueira, José F

    2013-04-01

    This study compared the incidence of deviation along S-shaped (double-curved) canals after glide path preparation with 2 nickel-titanium (NiTi) rotary pathfinding instruments and hand K-files. S-shaped canals from 60 training blocks were filled with ink, and preinstrumentation images were obtained by using a stereomicroscope. Glide path preparation was performed by an endodontist who used hand stainless steel K-files (up to size 20), rotary NiTi PathFile instruments (up to size 19), or rotary NiTi Scout RaCe instruments (up to size 20). Postinstrumentation images were taken by using exactly the same conditions as for the preinstrumentation images, and both pictures were superimposed. Differences along the S-shaped canal for the mesial and distal aspects were measured to evaluate the occurrence of deviation. Intragroup analysis showed that all instruments promoted some deviation in virtually all levels. Overall, regardless of the group, deviations were observed in the mesial wall at the canal terminus and at levels 4, 5, 6 and 7 mm and in the distal wall at levels 1, 2, and 3 mm. These levels corresponded to the inner walls of each curvature. Both rotary NiTi instruments performed significantly better than hand K-files at all levels (P < .05), except for PathFiles at the 0-mm level. ScoutRaCe instruments showed significantly better results than PathFiles at levels 0, 2, 3, 5, and 6 mm (P < .05). Findings suggest that rotary NiTi instruments are suitable for adequate glide path preparation because they promoted less deviation from the original canal anatomy when compared with hand-operated instruments. Of the 2 rotary pathfinding instruments, Scout RaCe showed an overall significantly better performance. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  4. GC-MS and LC-MS analysis of nerve agents in body fluids: intra-laboratory verification test using spiked plasma and urine samples.

    PubMed

    Koller, Marianne; Becker, Christian; Thiermann, Horst; Worek, Franz

    2010-05-15

    The purpose of this study was to check the applicability of different analytical methods for the identification of unknown nerve agents in human body fluids. Plasma and urine samples were spiked with nerve agents (plasma) or with their metabolites (urine) or were left blank. Seven random samples (35% of all samples) were selected for the verification test. Plasma was worked up for unchanged nerve agents and for regenerated nerve agents after fluoride-induced reactivation of nerve agent-inhibited butyrylcholinesterase. Both extracts were analysed by GC-MS. Metabolites were extracted from plasma and urine, respectively, and were analysed by LC-MS. The urinary metabolites and two blank samples could be identified without further measurements, plasma metabolites and blanks were identified in six of seven samples. The analysis of unchanged nerve agent provided five agents/blanks and the sixth agent after further investigation. The determination of the regenerated agents also provided only five clear findings during the first screening because of a rather noisy baseline. Therefore, the sample preparation was extended by a size exclusion step performed before addition of fluoride which visibly reduced baseline noise and thus improved identification of the two missing agents. The test clearly showed that verification should be performed by analysing more than one biomarker to ensure identification of the agent(s). Copyright (c) 2010 Elsevier B.V. All rights reserved.

  5. Human Carboxylesterase 1 Stereoselectively Binds the Nerve Agent Cyclosarin and Spontaneously Hydrolyzes the Nerve Agent Sarin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hemmert, Andrew C.; Otto, Tamara C.; Wierdl, Monika

    Organophosphorus (OP) nerve agents are potent toxins that inhibit cholinesterases and produce a rapid and lethal cholinergic crisis. Development of protein-based therapeutics is being pursued with the goal of preventing nerve agent toxicity and protecting against the long-term side effects of these agents. The drug-metabolizing enzyme human carboxylesterase 1 (hCE1) is a candidate protein-based therapeutic because of its similarity in structure and function to the cholinesterase targets of nerve agent poisoning. However, the ability of wild-type hCE1 to process the G-type nerve agents sarin and cyclosarin has not been determined. We report the crystal structure of hCE1 in complex withmore » the nerve agent cyclosarin. We further use stereoselective nerve agent analogs to establish that hCE1 exhibits a 1700- and 2900-fold preference for the P{sub R} enantiomers of analogs of soman and cyclosarin, respectively, and a 5-fold preference for the P{sub S} isomer of a sarin analog. Finally, we show that for enzyme inhibited by racemic mixtures of bona fide nerve agents, hCE1 spontaneously reactivates in the presence of sarin but not soman or cyclosarin. The addition of the neutral oxime 2,3-butanedione monoxime increases the rate of reactivation of hCE1 from sarin inhibition by more than 60-fold but has no effect on reactivation with the other agents examined. Taken together, these data demonstrate that hCE1 is only reactivated after inhibition with the more toxic P{sub S} isomer of sarin. These results provide important insights toward the long-term goal of designing novel forms of hCE1 to act as protein-based therapeutics for nerve agent detoxification.« less

  6. Preparation and Biological Study of 68Ga-DOTA-alendronate

    PubMed Central

    Fakhari, Ashraf; Jalilian, Amir R.; Johari-Daha, Fariba; Shafiee-Ardestani, Mehdi; Khalaj, Ali

    2016-01-01

    Objective(s): In line with previous research on the development of conjugated bisphosphonate ligands as new bone-avid agents, in this study, DOTA-conjugated alendronate (DOTA-ALN) was synthesized and evaluated after labeling with gallium-68 (68Ga). Methods: DOTA-ALN was synthesized and characterized, followed by 68Ga-DOTA-ALN preparation, using DOTA-ALN and 68GaCl3 (pH: 4-5) at 92-95° C for 10 min. Stability tests, hydroxyapatite assay, partition coefficient calculation, biodistribution studies, and imaging were performed on the developed agent in normal rats. Results: The complex was prepared with high radiochemical purity (>99% as depicted by radio thin-layer chromatography; specific activity: 310-320 GBq/mmol) after solid phase purification and was stabilized for up to 90 min with a log P value of -2.91. Maximum ligand binding (65%) was observed in the presence of 50 mg of hydroxyapatite; a major portion of the activity was excreted through the kidneys. With the exception of excretory organs, gastrointestinal tract organs, including the liver, intestine, and colon, showed significant uptake; however, the bone uptake was low (<1%) at 30 min after the injection. The data were also confirmed by sequential imaging at 30-90 min following the intravenous injection. Conclusion: The high solubility and anionic properties of the complex led to major renal excretion and low hydroxyapatite uptake; therefore, the complex failed to demonstrate bone imaging behaviors. PMID:27408898

  7. Representation in dynamical agents.

    PubMed

    Ward, Ronnie; Ward, Robert

    2009-04-01

    This paper extends experiments by Beer [Beer, R. D. (1996). Toward the evolution of dynamical neural networks for minimally cognitive behavior. In P. Maes, M. Mataric, J. Meyer, J. Pollack, & S. Wilson (Eds.), From animals to animats 4: Proceedings of the fourth international conference on simulation of adaptive behavior (pp. 421-429). MIT Press; Beer, R. D. (2003). The dynamics of active categorical perception in an evolved model agent (with commentary and response). Adaptive Behavior, 11 (4), 209-243] with an evolved, dynamical agent to further explore the question of representation in cognitive systems. Beer's environmentally-situated visual agent was controlled by a continuous-time recurrent neural network, and evolved to perform a categorical perception task, discriminating circles from diamonds. Despite the agent's high levels of discrimination performance, Beer found no evidence of internal representation in the best-evolved agent's nervous system. Here we examine the generality of this result. We evolved an agent for shape discrimination, and performed extensive behavioral analyses to test for representation. In this case we find that agents developed to discriminate equal-width shapes exhibit what Clark [Clark, A. (1997). The dynamical challenge. Cognitive Science, 21 (4), 461-481] calls "weak-substantive representation". The agent had internal configurations that (1) were understandably related to the object in the environment, and (2) were functionally used in a task relevant way when the target was not visible to the agent.

  8. Military chemical warfare agent human subjects testing: part 2--long-term health effects among participants of U.S. military chemical warfare agent testing.

    PubMed

    Brown, Mark

    2009-10-01

    Military chemical warfare agent testing from World War I to 1975 produced thousands of veterans with concerns about how their participation affected their health. A companion article describes the history of these experiments, and how the lack of clinical data hampers evaluation of long-term health consequences. Conversely, much information is available about specific agents tested and their long-term health effects in other populations, which may be invaluable for helping clinicians respond effectively to the health care and other needs of affected veterans. The following review describes tested agents and their known long-term health consequences. Although hundreds of chemicals were tested, they fall into only about a half-dozen pharmaceutical classes, including common pharmaceuticals; anticholinesterase agents including military nerve agents and pesticides; anticholinergic glycolic acid esters such as atropine; acetylcholine reactivators such as 2-PAM; psychoactive compounds including cannabinoids, phencyclidine, and LSD; and irritants including tear gas and riot control agents.

  9. Preparing culture change agents for academic medicine in a multi-institutional consortium: the C - change learning action network.

    PubMed

    Pololi, Linda H; Krupat, Edward; Schnell, Eugene R; Kern, David E

    2013-01-01

    Research suggests an ongoing need for change in the culture of academic medicine. This article describes the structure, activities and evaluation of a culture change project: the C - Change Learning Action Network (LAN) and its impact on participants. The LAN was developed to create the experience of a culture that would prepare participants to facilitate a culture in academic medicine that would be more collaborative, inclusive, relational, and that supports the humanity and vitality of faculty. Purposefully diverse faculty, leaders, and deans from 5 US medical schools convened in 2 1/2-day meetings biannually over 4 years. LAN meetings employed experiential, cognitive, and affective learning modes; innovative dialogue strategies; and reflective practice aimed at facilitating deep dialogue, relationship formation, collaboration, authenticity, and transformative learning to help members experience the desired culture. Robust aggregated qualitative and quantitative data collected from the 5 schools were used to inform and stimulate culture-change plans. Quantitative and qualitative evaluation methods were used. Participants indicated that a safe, supportive, inclusive, collaborative culture was established in LAN and highly valued. LAN members reported a deepened understanding of organizational change, new and valued interpersonal connections, increased motivation and resilience, new skills and approaches, increased self-awareness and personal growth, emotional connection to the issues of diversity and inclusion, and application of new learnings in their work. A carefully designed multi-institutional learning community can transform the way participants experience and view institutional culture. It can motivate and prepare them to be change agents in their own institutions. Copyright © 2013 The Alliance for Continuing Education in the Health Professions, the Society for Academic Continuing Medical Education, and the Council on CME, Association for Hospital Medical

  10. [Research of preparation craft of Danshen phenolic acid fast release unit in multi-drug delivery system of Tongmai micro-pellets].

    PubMed

    Chen, Bin; Xiao, Wei; Jia, Xiao-Bin; Huang, Yang

    2012-07-01

    To prepare Danshen phenolic acid fast release micro-pellets and study its preparation craft. The factors which could impact yield, extrude shaping, dissolution of Danshen phenolic acid micro-pellets such as wetting agent, drug loading dose, adjuvant, lactose dose, disintegrant, CMS-Na dose and wetting agent dose was investigated. The optimum preparation craft of Danshen phenolic acid fast release micro-pellets was screened out by orhogonal design. Formula of Danshen phenolic acid fast release micro-pellets was calculated as volume dose 50 g. The formula was as follows: principal agent 22.5 g, lactose 5 g, CMS-Na 2 g, MCC 20.5 g, 27 mL 30% ethanol as wetting agent. Extrusion-spheronization was applied. The optimum conditions were screened out as follows: extrusion frequency (25 Hz), spheronization machine frequency (50 Hz), spheronization time (4 min). The process was scientific and rational. The preparation is stable settles basis for multi-drug delivery system of Tongmai micro-pellets.

  11. 75 FR 43110 - User Fees Relating to Enrollment and Preparer Tax Identification Numbers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... certified public accountants, attorneys, enrolled agents, or registered tax return preparers are denied.... Except as provided in any transitional period, only attorneys, certified public accountants, enrolled... public accountants (NAICS code 541211). Entities identified as tax preparation services and offices of...

  12. Effect of nanoparticle encapsulation on the photostability of the sunscreen agent, 2-ethylhexyl-p-methoxycinnamate.

    PubMed

    Perugini, P; Simeoni, S; Scalia, S; Genta, I; Modena, T; Conti, B; Pavanetto, F

    2002-10-10

    The aim of this study was to investigate the influence of nanoparticle-based systems on the light-induced decomposition of the sunscreen agent, trans-2-ethylhexyl-p-methoxycinnamate (trans-EHMC). Ethylcellulose (EC) and poly-D,L-lactide-co-glycolide (PLGA) were used as biocompatible polymers for the preparation of the particulate systems. The "salting out" method was used for nanoparticle preparation and several variables were evaluated in order to optimize product characteristics. The photodegradation of the sunscreen agent in emulsion vehicles was reduced by encapsulation into the PLGA nanoparticles (the extent of degradation was 35.3% for the sunscreen-loaded nanoparticles compared to 52.3% for free trans-EHMC) whereas the EC nanoparticle system had no significant effect. Therefore, PLGA nanoparticles loaded with trans-EHMC improve the photostability of the sunscreen agent.

  13. Preparation of active antibacterial LDPE surface through multistep physicochemical approach: I. Allylamine grafting, attachment of antibacterial agent and antibacterial activity assessment.

    PubMed

    Bílek, František; Křížová, Táňa; Lehocký, Marián

    2011-11-01

    Low-density polyethylene (LDPE) samples were treated in air plasma discharge, coated by polyallyamine brush thought copolymeric grafting surface-from reaction and deposited four common antibacterial agents (benzalkonium chloride, bronopol, chlorhexidine and triclosan) to gain material with active antibacterial properties. Surface characteristics were evaluated by static contact angle measurement with surface energy evaluation ATR-FTIR, X-ray Photoelectron Spectroscopy (XPS) and SEM analysis. Inhibition zone on agar was used as in vitro test of antibacterial properties on two representative gram positive Staphylococcus aureus (S. aureus) and gram negative Escherichia coli (E. coli) strains. It was confirmed, that after grafting of polyallyamine, more antibacterial agent is immobilized on the surface. The highest increase of antibacterial activity was observed by the sample containing triclosan. Samples covered by bronopol did not show significant antibacterial activity. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. PREPARATION OF HIGH PURITY UF$sub 4$

    DOEpatents

    Magner, J.E.; Long, R.S.; Ellis, D.A.; Grinstead, R.R.

    1962-04-17

    S>A process for preparing very highly pure uranous tetrafluoride from impure uranium laden solvent extraction strip solutions, ion exchange process and resin-inpulp process eluate solutions which are at least 8M in hydrochloric acid is described. The process first comprises treating any of the above-mentioned solutions with a reducing agent to reduce the uranium to the + 4 oxidation state, and then contacting the reduced solution with an extractant phase comprising about 10 to 70% of tri-butyl phosphate in an organic solvent-diluent selected from benzene, ethyl-benzene, chlorobenzene, xylene, kerosene, or the like. The uranium is extracted into the extractant phase and is subsequently precipitated by treating the extractant with an aqueous fluoride solution. The highly pure uranous tetrafluoride precipitate is separated from the phases and recovered for subsequent utilization. (AEC)

  15. Infrared and Raman spectroscopy study of AsS chalcogenide films prepared by plasma-enhanced chemical vapor deposition.

    PubMed

    Mochalov, Leonid; Dorosz, Dominik; Kudryashov, Mikhail; Nezhdanov, Aleksey; Usanov, Dmitry; Gogova, Daniela; Zelentsov, Sergey; Boryakov, Aleksey; Mashin, Alexandr

    2018-03-15

    AsS chalcogenide films, where As content is 60-40at.%, have been prepared via a RF non-equilibrium low-temperature argon plasma discharge, using volatile As and S as the precursors. Optical properties of the films were studied in UV-visible-NIR region in the range from 0.2 to 2.5μm. Infrared and Raman spectroscopy have been employed for the elucidation of the molecular structure of the newly developed material. It was established that PECVD films possess a higher degree of transparency (up to 80%) and a wider transparency window (>20μm) in comparison with the "usual" AsS thin films, prepared by different thermal methods, which is highly advantageous for certain applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Preparation and in vitro characterization of chitosan nanobubbles as theranostic agents.

    PubMed

    Cavalli, R; Argenziano, M; Vigna, E; Giustetto, P; Torres, E; Aime, S; Terreno, E

    2015-05-01

    Theranostic delivery systems are nanostructures that combine the modality of therapy and diagnostic imaging. Polymeric micro- and nanobubbles, spherical vesicles containing a gas core, have been proposed as new theranostic carriers for MRI-guided therapy. In this study, chitosan nanobubbles were purposely tuned for the co-delivery of prednisolone phosphate and a Gd(III) complex, as therapeutic and MRI diagnostic agent, respectively. Perfluoropentane was used for filling up the internal core of the formulation. These theranostic nanobubbles showed diameters of about 500nm and a positive surface charge that allows the interaction with the negatively charged Gd-DOTP complex. Pluronic F68 was added to the nanobubble aqueous suspension as stabilizer agent. The encapsulation efficiency was good for both the active compounds, and a prolonged drug release profile was observed in vitro. The effect of ultrasound stimulation on prednisolone phosphate release was evaluated at 37°C. A marked increase on drug release kinetics with no burst effect was obtained after the exposure of the system to ultrasound. Furthermore, the relaxivity of the MRI probe changed upon incorporation in the nanobubble shell, thereby offering interesting opportunity in dual MRI-US experiments. The ultrasound characterization showed a good in vitro echogenicity of the theranostic nanobubbles. In summary, chitosan drug-loaded nanobubbles with Gd(III) complex bound to their shell might be considered a new platform for imaging and drug delivery with the potential of improving anti-cancer treatments. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Insights into Comparative Antimicrobial Efficacies of Synthetic and Organic Agents: The Case of ZnS Nanoparticles and Zingiber officinale Rosc.

    NASA Astrophysics Data System (ADS)

    Obidi, O. F.; Nejo, A. O.; Ayeni, R. A.; Revaprasadu, N.

    2018-03-01

    The differences among the antimicrobial activities of synthetic nanoparticles (NPs), organic agents and conventional antibiotics against human pathogens are little known. We compared the antimicrobial activities of aqueous, ethanol and ethyl acetate extracts of Zingiber officinale rhizomes with ZnS NPs and tetracycline/nystatin using agar-diffusion techniques. Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and ultraviolet spectroscopy were used to characterize ZnS NPs. At 100 mg/ml, ethanol and ethyl acetate extract inhibited Acinetobacter baumannii, Salmonella typhimurium, Enterococcus faecium, Shigella flexneri, Klebsiella pneumoniae, Staphylococcus epidermidis and Candida albicans with zones of inhibition (ZOI) ranging between 0-42 mm and 0-39 mm, respectively. Candida albicans had a remarkable ZOI of 42 mm and 22 mm from ethanol and ZnS NPs compared with 20 mm from conventional nystatin. TEM and FTIR revealed spherically shaped polydispersed NPs with particle size of 12.5 nm and the role of banana peel extracts in ZnS NPs synthesis. Organic and synthetic NPs proved potential alternatives to conventional antimicrobial agents.

  18. Insights into Comparative Antimicrobial Efficacies of Synthetic and Organic Agents: The Case of ZnS Nanoparticles and Zingiber officinale Rosc.

    NASA Astrophysics Data System (ADS)

    Obidi, O. F.; Nejo, A. O.; Ayeni, R. A.; Revaprasadu, N.

    2018-06-01

    The differences among the antimicrobial activities of synthetic nanoparticles (NPs), organic agents and conventional antibiotics against human pathogens are little known. We compared the antimicrobial activities of aqueous, ethanol and ethyl acetate extracts of Zingiber officinale rhizomes with ZnS NPs and tetracycline/nystatin using agar-diffusion techniques. Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and ultraviolet spectroscopy were used to characterize ZnS NPs. At 100 mg/ml, ethanol and ethyl acetate extract inhibited Acinetobacter baumannii, Salmonella typhimurium, Enterococcus faecium, Shigella flexneri, Klebsiella pneumoniae, Staphylococcus epidermidis and Candida albicans with zones of inhibition (ZOI) ranging between 0-42 mm and 0-39 mm, respectively. Candida albicans had a remarkable ZOI of 42 mm and 22 mm from ethanol and ZnS NPs compared with 20 mm from conventional nystatin. TEM and FTIR revealed spherically shaped polydispersed NPs with particle size of 12.5 nm and the role of banana peel extracts in ZnS NPs synthesis. Organic and synthetic NPs proved potential alternatives to conventional antimicrobial agents.

  19. Cast-In-Situ, Large-Sized Monolithic Silica Xerogel Prepared in Aqueous System.

    PubMed

    Ding, Wenhui; Wang, Xiaodong; Chen, Dong; Li, Tiemin; Shen, Jun

    2018-05-15

    This paper reports the preparation of cast-in-situ, large-sized monolithic silica xerogels by a two-step acid⁻base catalyzed approach under ambient pressure drying. Low-cost industrial silica sol and deionized water were used as the silicon source and the solvent, respectively. Hexadecetyltrimethylammonium bromide (CTAB) was used as a modification agent. Different amounts of polyethylene glycol 400 (PEG400) was added as a pore-forming agent. The prepared silica xerogels under ambient pressure drying have a mesoporous structure with a low density of 221 mg·cm -3 and a thermal conductivity of 0.0428 W·m -1 ·K -1 . The low-cost and facile preparation process, as well as the superior performance of the monolithic silica xerogels make it a promising candidate for industrial thermal insulation materials.

  20. Properties of realgar bioleaching using an extremely acidophilic bacterium and its antitumor mechanism as an anticancer agent.

    PubMed

    Chen, Peng; Xu, Ruixiang; Yan, Lei; Wu, Zhengrong; Wei, Yan; Zhao, Wenbin; Wang, Xin; Xie, Qinjian; Li, Hongyu

    2017-05-22

    Realgar is a naturally occurring arsenic sulfide (or Xionghuang, in Chinese). It contains over 90% tetra-arsenic tetra-sulfide (As 4 S 4 ). Currently, realgar has been confirmed the antitumor activities, both in vitro and in vivo, of realgar extracted using Acidithiobacillus ferrooxidans (A. ferrooxidans). Bioleaching, a new technology to greatly improve the use rate of arsenic extraction from realgar using bacteria, is a novel methodology that addressed a limitation of the traditional method for realgar preparation. The present systematic review reports on the research progress in realgar bioleaching and its antitumor mechanism as an anticancer agent. A total of 93 research articles that report on the biological activity of extracts from realgar using bacteria and its preparation were presented in this review. The realgar bioleaching solution (RBS) works by inducing apoptosis when it is used to treat tumor cells in vitro and in vivo. When it is used to treat animal model organisms in vivo, such as mice and Caenorhabditis elegans, tumor tissues grew more slowly, with mass necrosis. Meanwhile, the agent also showed obvious inhibition of tumor cell growth. Bioleaching technology greatly improves the utilization of realgar and is a novel methodology to improve the traditional method.

  1. Dynamics and Steady States in Excitable Mobile Agent Systems

    NASA Astrophysics Data System (ADS)

    Peruani, Fernando; Sibona, Gustavo J.

    2008-04-01

    We study the spreading of excitations in 2D systems of mobile agents where the excitation is transmitted when a quiescent agent keeps contact with an excited one during a nonvanishing time. We show that the steady states strongly depend on the spatial agent dynamics. Moreover, the coupling between exposition time (ω) and agent-agent contact rate (CR) becomes crucial to understand the excitation dynamics, which exhibits three regimes with CR: no excitation for low CR, an excited regime in which the number of quiescent agents (S) is inversely proportional to CR, and, for high CR, a novel third regime, model dependent, where S scales with an exponent ξ-1, with ξ being the scaling exponent of ω with CR.

  2. Synthesis of a New Titanate Coupling Agent for the Modification of Calcium Sulfate Whisker in Poly(Vinyl Chloride) Composite

    PubMed Central

    Yuan, Wenjin; Lu, Yunhua; Xu, Shiai

    2016-01-01

    A new titanate coupling agent synthesized from polyethylene glycol (PEG), isooctyl alcohol, and phosphorus pentoxide (P2O5) was used for the modification of calcium sulfate whiskers (CSWs) and the preparation of high-performance CSW/poly(vinyl chloride) (PVC) composites. The titanate coupling agent (sTi) and the modified CSWs (sTi–CSW) were characterized by Fourier transform infrared (FTIR) spectroscopy, and the mechanical, dynamic mechanical, and heat resistant properties and thermostability of sTi–CSW/PVC and CSW/PVC composites were compared. The results show that sTi–CSW/PVC composite with 10 wt. % whisker content has the best performance, and its tensile strength, Young’s modulus, elongation at break, break strength, and impact strength are 67.2 MPa, 1926 MPa, 233%, 51.1 MPa, and 12.75 KJ·m−2, with an increase of 20.9%, 11.5%, 145.3%, 24.6%, and 65.4% compared to that of CSW/PVC composite at the same whisker content. As the whisker content increases, the storage modulus increases, the Vicat softening temperature decreases slightly, and the glass transition temperature increases at first and then decreases. PMID:28773748

  3. Biocatalytic organic synthesis of optically pure (S)-scoulerine and berbine and benzylisoquinoline alkaloids.

    PubMed

    Schrittwieser, Joerg H; Resch, Verena; Wallner, Silvia; Lienhart, Wolf-Dieter; Sattler, Johann H; Resch, Jasmin; Macheroux, Peter; Kroutil, Wolfgang

    2011-08-19

    A chemoenzymatic approach for the asymmetric total synthesis of the title compounds is described that employs an enantioselective oxidative C-C bond formation catalyzed by berberine bridge enzyme (BBE) in the asymmetric key step. This unique reaction yielded enantiomerically pure (R)-benzylisoquinoline derivatives and (S)-berbines such as the natural product (S)-scoulerine, a sedative and muscle relaxing agent. The racemic substrates rac-1 required for the biotransformation were prepared in 4-8 linear steps using either a Bischler-Napieralski cyclization or a C1-Cα alkylation approach. The chemoenzymatic synthesis was applied to the preparation of fourteen enantiomerically pure alkaloids, including the natural products (S)-scoulerine and (R)-reticuline, and gave overall yields of up to 20% over 5-9 linear steps.

  4. Computerized bioterrorism education and training for nurses on bioterrorism attack agents.

    PubMed

    Nyamathi, Adeline M; Casillas, Adrian; King, Major L; Gresham, Louise; Pierce, Elaine; Farb, Daniel; Wiechmann, Carrie; Weichmann, Carrie

    2010-08-01

    Biological agents have the ability to cause large-scale mass casualties. For this reason, their likely use in future terrorist attacks is a concern for national security. Recent studies show that nurses are ill prepared to deal with agents used in biological warfare. Achieving a goal for bioterrorism preparedness is directly linked to comprehensive education and training that enables first-line responders such as nurses to diagnose infectious agents rapidly. The study evaluated participants' responses to biological agents using a computerized bioterrorism education and training program versus a standard bioterrorism education and training program. Both programs improved participants' ability to complete and solve case studies involving the identification of specific biological agents. Participants in the computerized bioterrorism education and training program were more likely to solve the cases critically without reliance on expert consultants. However, participants in the standard bioterrorism education and training program reduced the use of unnecessary diagnostic tests.

  5. Electrochemical Sensor Based on Rh(III) Ion-Imprinted Polymer as a New Modifying Agent for Rhodium Determination.

    PubMed

    Bai, Huiping; Xiong, Caiyun; Wang, Chunqiong; Liu, Peng; Dong, Su; Cao, Qiue

    2018-05-01

    A rhodium (III) ion carbon paste electrode (CPE) based on an ion imprinted polymer (IIP) as a new modifying agent has been prepared and studied. Rh(III) ion imprinted polymer was synthesized by copolymerization of acrylamide-Rh(III) complex and ethylene glycol dimethacrylate according to the precipitation polymerization. Acrylamide acted as both functional monomer and complexing agent to create selective coordination sites in a cross-linked polymer. The ion imprinted carbon paste electrode (IIP-CPE) was prepared by mixing rhodium IIP-nanoparticles and graphite powder in n-eicosane as an adhesive and then embedding them in a Teflon tube. Amperometric i-t curve method was applied as the determination technique. Several parameters, including the functional monomer, molar ratio of template, monomer and cross-linking agent, the amounts of IIP, the applied potential, the buffer solution and pH have been studied. According to the results, IIP-CPE showed a considerably higher response in comparison with the electrode embedded with non-imprinted polymer (NIP), indicating the formation of suitable recognition sites in the IIP structure during the polymerization stage. The introduced electrode showed a linear range of 1.00×10-8~3.0×10-5 mol·L-1 and detection limit of 6.0 nmol L-1 (S/N = 3). The IIP-CPE was successfully applied for the trace rhodium determination in catalyst and plant samples with RSD of less than 3.3% (n = 5) and recoveries in the range of 95.5~102.5%.

  6. Assessment of the best N(3-) donors in preparation of [M(N)(PNP)]-based (M=(99m)Tc-; (188)Re) target-specific radiopharmaceuticals: Comparison among succinic dihydrazide (SDH), N-methyl-S-methyl dithiocarbazate (HDTCZ) and PEGylated N-methyl-S-methyl dithiocarbazate (HO2C-PEG600-DTCZ).

    PubMed

    Carta, Davide; Jentschel, Christian; Thieme, Stefan; Salvarese, Nicola; Morellato, Nicolò; Refosco, Fiorenzo; Ruzza, Paolo; Bergmann, Ralf; Pietzsch, Hans-Jurgen; Bolzati, Cristina

    2014-08-01

    Succinic dihydrazide (SDH), N-methyl-S-methyl dithiocarbazate (HDTCZ) and PEGylated N-methyl-S-methyl dithiocarbazate (HO2C-PEG600-DTCZ) are nitrido nitrogen atom donors employed for the preparation of nitride [M(N)]-complexes (M=(99m)Tc and (188)Re). This study aims to compare the capability and the efficiency of these three N(3-) group donors, in the preparation of [M(N)PNP]-based target-specific compounds (M=(99m)Tc, (188)Re; PNP=aminodiphosphine). For this purpose, three different kit formulations (SDH kit; HO2C-PEG600-DTCZ kit; HDTCZ kit) were assembled and used in the preparation of [M(N)(cys~)(PNP3)](0/+) complexes (cys~=cysteine derivate ligands). For each formulation, the radiochemical yield (RCY) of the [M(N)(~cys)(PNP3)] compounds, was determined by HPLC. The deviation of the percentage of RCY, due to changes in concentration of the N(3-) donors and of the exchanging ligand, was determined. For (99m)Tc, data clearly show that HDTCZ is the most efficient donor of N(3-); however, SDH is the most suitable nitrido nitrogen atom donor for the preparation of [(99m)Tc(N)(PNP)]-based target-specific agents with high specific activity. When HO2C-PEG600-DTCZ or HDTCZ are used in N(3-) donation, high amounts of the exchanging ligand (10(-4)M) were required for the formation of the final complex in acceptable yield. The possibility to use microgram amounts of HDTCZ also in [(188)Re(N)] preparation (0.050mg) reduces its ability to compete in ligand exchange reactions, minimizing the quantity of chelators required to obtain the final complex in high yield. This finding can be exploit for increasing the radiolabeling efficiency in [(188)Re(N)]-radiopharmaceutical preparations compared to the previously reported HDTCZ-based procedure, notwithstanding a purification process could be necessary to improve the specific activity of the complexes. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. [Utilization of polymeric micelle magnetic resonance imaging (MRI) contrast agent for theranostic system].

    PubMed

    Shiraishi, Kouichi

    2013-01-01

    We applied a polymeric micelle carrier system for the targeting of a magnetic resonance imaging (MRI) contrast agent. Prepared polymeric micelle MRI contrast agent exhibited a long circulation characteristic in blood, and considerable amount of the contrast agent was found to accumulate in colon 26 solid tumor by the EPR effect. The signal intensities of tumor area showed 2-folds increase in T1-weighted images at 24 h after i.v. injection. To observe enhancement of the EPR effect by Cderiv pretreatment on tumor targeting, we used the contrast agent for the evaluation by means of MRI. Cderiv pretreatment significantly enhanced tumor accumulation of the contrast agent. Interestingly, very high signal intensity in tumor region was found at 24 h after the contrast agent injection in Cderiv pretreated mice. The contrast agent visualized a microenvironmental change in tumor. These results indicate that the contrast agent exhibits potential use for tumor diagnostic agent. To combine with a polymeric micelle carrier system for therapeutic agent, the usage of the combination makes a new concept of "theranostic" for a better cancer treatment.

  8. Diethylenetriaminepentaacetic acid-gadolinium (DTPA-Gd)-conjugated polysuccinimide derivatives as magnetic resonance imaging contrast agents.

    PubMed

    Lee, Ha Young; Jee, Hye Won; Seo, Sung Mi; Kwak, Byung Kook; Khang, Gilson; Cho, Sun Hang

    2006-01-01

    Biocompatible polysuccinimide (PSI) derivatives conjugated with diethylenetriaminepentaacetic acid gadolinium (DTPA-Gd) were prepared as magnetic resonance imaging (MRI) contrast agents. In this study, we synthesized PSI derivatives incorporating methoxy-poly(ethylene glycol) (mPEG) as hydrophilic ligand, hexadecylamine as hydrophobic ligand, and DTPA-Gd as contrast agent. PSI was synthesized by the polycondensation polymerization of aspartic acid. All the synthesized materials were characterized by proton nuclear magnetic resonance (1H NMR). Critical micellization concentrations were determined using fluorescent probes (pyrene). Micelle size and shape were measured by electro-photometer light scattering (ELS) and atomic force microscopy (AFM). The formed micelle size ranged from 100 to 300 nm. The T1-weighted MR images of the phantom prepared with PSI-mPEG-C16-(DTPA-Gd) were obtained in a 3.0 T clinical MR imager, and the conjugates showed a great potential as MRI contrast agents.

  9. High potential of Mn-doped ZnS nanoparticles with different dopant concentrations as novel MRI contrast agents: synthesis and in vitro relaxivity studies

    NASA Astrophysics Data System (ADS)

    Jahanbin, Tania; Gaceur, Meriem; Gros-Dagnac, Hélène; Benderbous, Soraya; Merah, Souad Ammar

    2015-06-01

    Over several decades, metal-doped quantum dots (QDs) with core-shell structure have been studied as dual probes: fluorescence and magnetic resonance imaging (MRI) probes (Dixit et al., Mater Lett 63(30):2669-2671, 2009). However, metal-doped nanoparticles, in which the majority of metal ions are close to the surface, can affect their efficacy as MRI contrast agents (CAs). In this context, herein the high potential of synthesized Mn-doped ZnS QDs via polyol method as imaging probe is demonstrated. The mean diameters of QDs were measured via transmission electron microscopy (TEM) and X-ray diffraction (XRD). Optical and magnetic properties of MnZnS nanoparticles were characterized using fluorescence spectroscopy and super quanducting interference devices magnetometer and electron paramagnetic resonance system, respectively. T1- and T2-weighted images of nanoparticles in aqueous solution were acquired from spin-echo sequences at 3 T. From TEM images and XRD spectra of the prepared nanoparticles, it is observed that the average diameter of particles does not significantly change with Mn dopant content ( 1.6-1.9 nm). All three samples exhibit broad blue emission under UV light excitation. According to the MRI studies, MnZnS nanoparticles generate strong T1 contrast enhancement (bright T1-weighted images) at the low concentration (<0.1 mM). The MnZnS nanoparticles exhibit the high longitudinal ( r 1) relaxivity that increases from 20.34 to 75.5 mM-1 s-1 with the Mn dopant contents varying between 10 and 30 %. Strong signal intensity on T1-weighted images and high r 1 with {r2 }/{r_{1 }} ≈ 1 can demonstrate the high potential of the synthesized Mn:ZnS nanoparticles, which can serve as an effective T1 CA.

  10. Charge transfer in crystalline germanium/monolayer MoS 2 heterostructures prepared by chemical vapor deposition

    DOE PAGES

    Lin, Yung-Chen; Bilgin, Ismail; Ahmed, Towfiq; ...

    2016-09-21

    Heterostructuring provides novel opportunities for exploring emergent phenomena and applications by developing designed properties beyond those of homogeneous materials. Advances in nanoscience enable the preparation of heterostructures formed incommensurate materials. Two-dimensional (2D) materials, such as graphene and transition metal dichalcogenides, are of particular interest due to their distinct physical characteristics. There have been recent changes in new research areas related to 2D/2D heterostructures. But, other heterostructures such as 2D/three-dimensional (3D) materials have not been thoroughly studied yet although the growth of 3D materials on 2D materials creating 2D/3D heterostructures with exceptional carrier transport properties has been reported. Here also wemore » report a novel heterostructure composed of Ge and monolayer MoS 2, prepared by chemical vapor deposition. A single crystalline Ge (110) thin film was grown on monolayer MoS 2. The electrical characteristics of Ge and MoS 2 in the Ge/MoS 2 heterostructure were remarkably different from those of isolated Ge and MoS 2. The field-effect conductivity type of the monolayer MoS 2 is converted from n-type to p-type by growth of the Ge thin film on top of it. Undoped Ge on MoS 2 is highly conducting. The observations can be explained by charge transfer in the heterostructure as opposed to chemical doping via the incorporation of impurities, based on our first-principles calculations.« less

  11. CdS nanoparticles-enhanced chemiluminescence and determination of baicalin in pharmaceutical preparations.

    PubMed

    Chen, Xiaolan; Tan, Xinmei; Wang, Jianxiu

    2013-01-01

    CdS nanoparticles (CdS NPs) of different sizes were synthesized by the citrate reduction method. It was found that CdS NPs could enhance the chemiluminescence (CL) of the luminol-potassium ferricyanide system and baicalin could inhibit CdS NPs-enhanced luminol-potassium ferricyanide CL signals in alkaline solution. Based on this inhibition, a flow-injection CL method was established for determination of baicalin in pharmaceutical preparations and human urine samples. Under optimized conditions, the linear range for determination of baicalin was 5.0 x 10(-6) to 1.0 x 10(-3) g/L. The detection limit at a signal-to-noise ratio of 3 was 1.7 x 10(-6) g/L. CL spectra, UV-visible spectra and transmission electron microscopy (TEM) were used to investigate the CL mechanism. The method described is simple, selective and obviates the need of extensive sample pretreatment. Copyright © 2012 John Wiley & Sons, Ltd.

  12. The Use of Published Clinical Study Reports to Support U.S. Food and Drug Administration Approval of Imaging Agents.

    PubMed

    Rieves, Dwaine; Jacobs, Paula

    2016-12-01

    Pharmaceutical companies typically perform prospective, multicenter phase 3 clinical studies to support approval of a new imaging agent by the U.S. Food and Drug Administration (FDA). In uncommon situations, the FDA has approved imaging agents based solely, or in large part, on the clinical study experience described in published reports, including reports of exploratory (i.e., phase 1 or 2) studies performed at a single clinical site. We performed a survey of published reports to assess the potential of the reported information to support FDA approval of a commonly cited investigational imaging agent. Our survey revealed critical data limitations in most publications, all of which reported exploratory clinical studies. Here we summarize the precedent for FDA approval of imaging agents using effectiveness data from publications, FDA guidance, and our experience in reviewing publications. We also present a key-data checklist for investigators to consider in the design, conduct, and reporting of exploratory clinical studies for publication. We encourage editors and peer reviewers to consider requiring these key data when reviewing these reports for publication. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  13. Novel polymers and method of preparing same

    NASA Technical Reports Server (NTRS)

    Hirshfield, S. M. (Inventor)

    1973-01-01

    Polymers are prepared with terminal functional groups by reacting a compound selected from the group consisting of lithium p-lithiophenoxide and tetrabutylammonium p-lithiophenoxide as an initiator with material such as butadiene. The resulting functionally terminated new polymers are then capable of reacting with coupling agents to form star polymers.

  14. Edible Bird’s nest extract as a chondro-protective agent for human chondrocytes isolated from osteoarthritic knee: in vitro study

    PubMed Central

    2013-01-01

    Background Osteoarthritis (OA) is a degenerative joint disease that results in the destruction of cartilage. Edible Bird’s Nest (EBN) extract contains important components, which can reduce the progression of osteoarthritis and helps in the regeneration of the cartilage. The present study aimed to investigate the effect of EBN extract on the catabolic and anabolic activities of the human articular chondrocytes (HACs) isolated from the knee joint of patients with OA. Methods A single batch of EBN extract was prepared with hot-water extraction and coded as HMG. HACs were isolated from the knee joint cartilage removed during surgery. The optimum concentration of HMG for HAC cultures was determined using MTT assay. The effect of HMG on the catabolic and anabolic genes’ expression in HACs was measured by real-time PCR. The total amount of prostaglandin E2 (PGE2) production was determined by ELISA method, and the total sulphated glycosaminoglycan (GAGs) production was quantified by 1,9-dimethylmethylene blue (DMMB) assay. Results MTT assay showed 0.50% - 1.00% HMG supplementation promoted HACs proliferation. HMG supplementation was able to reduce the catabolic genes’ expression in cultured HACs such as matrix metalloproteinases (MMP1 & MMP3), Interleukin 1, 6 and 8 (IL-1, IL-6 & IL-8), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). Prostaglandin E2 (PGE2) production was significantly reduced in HAC cultures supplemented with HMG. With regard to anabolic activity assessment, type II collagen, Aggrecan and SOX-9 gene expression as well as sGAG production was increased in the HMG supplemented groups. Conclusion Edible Bird’s Nest extract coded as HMG demonstrated chondro-protection ability on human articular chondrocytes in vitro. It reduced catabolic activities and increased cartilage extracellular matrix synthesis. It is concluded that HMG is a potential agent in the treatment of osteoarthritis. PMID:23339380

  15. [Preparation and characterization of a polyvinylpyrrolidone water-based magnetic fluid].

    PubMed

    Xie, Jian-feng; Zhang, Yang-de; Zeng, Zhao-wu; Wang, Xiao-li; Liu, Xing-yan; Zhou, Wei-hua

    2008-03-01

    To prepare a stable water-based magnetic fluid. A water-based magnetic fluid was prepared by addition of polyvinylpyrrolidone (PVP) as the coating agent for the magnetic particles. After preparation of Fe3O4 by co-precipitation method, PVP was added for its coating, followed by ultrasonic agitation and purification. The magnetic nanoparticles of homogeneously small size and water-based magnetic fluid were obtained, which had good dispersion in water with strong magnetism. PVP can be used as a surfactant to stabilize the magnetic fluid.

  16. Dual Rationality and Deliberative Agents

    NASA Astrophysics Data System (ADS)

    Debenham, John; Sierra, Carles

    Human agents deliberate using models based on reason for only a minute proportion of the decisions that they make. In stark contrast, the deliberation of artificial agents is heavily dominated by formal models based on reason such as game theory, decision theory and logic—despite that fact that formal reasoning will not necessarily lead to superior real-world decisions. Further the Nobel Laureate Friedrich Hayek warns us of the ‘fatal conceit’ in controlling deliberative systems using models based on reason as the particular model chosen will then shape the system’s future and either impede, or eventually destroy, the subtle evolutionary processes that are an integral part of human systems and institutions, and are crucial to their evolution and long-term survival. We describe an architecture for artificial agents that is founded on Hayek’s two rationalities and supports the two forms of deliberation used by mankind.

  17. Is exposure to Agent Orange a risk factor for hepatocellular cancer?-A single-center retrospective study in the U.S. veteran population.

    PubMed

    Krishnamurthy, Padmini; Hazratjee, Nyla; Opris, Dan; Agrawal, Sangeeta; Markert, Ronald

    2016-06-01

    Approximately 15% to 35% of those with chronic hepatitis C (CHC) related cirrhosis will develop hepatocellular cancer (HCC). With this burden increasing across the globe, identification of risk factors for HCC has become imperative. Exposure to Agent Orange has been implicated as a possible risk factor for liver cancer in a study from the Republic of Korea. However, there has been no study in U.S. veterans with CHC and cirrhosis that has evaluated exposure to Agent Orange as a risk factor for HCC. We conducted a retrospective study of U.S. military veterans diagnosed with CHC and cirrhosis over a period of 14 years to evaluate potential risk factors for HCC including exposure to Agent Orange. We retrospectively reviewed 390 patients with confirmed CHC-related cirrhosis between 2000 and 2013 and identified patients with HCC. We compared demographic, laboratory, and other clinical characteristics of patients with and without HCC. The mean age of the cohort was 51 years (SD =7.5), with the majority being male (98.5%). Seventy-nine of 390 (20.2%) patients developed HCC, diagnosed on average 8 (SD =4.8) years after diagnosis of CHC. Nearly half (49.4%) were Childs A, 40.5% were Childs B, and 10.1% were Childs C. HCC patients were more likely to be African American than non-HCC patients (40.5% vs. 25.4%, P=0.009) and to be addicted to alcohol (86.1% vs. 74.3%, P=0.027). A trend toward significance was seen in the HCC group for exposure to Agent Orange (16.5% vs. 10.0%, P=0.10) and smoking addiction (88.6% vs. 80.7%, P=0.10). Consequently, race, alcohol addiction, Agent Orange exposure, and smoking addiction were included in the multivariable logistic regression (MLR) analysis. Alcohol addiction [odds ratio (OR) =2.17; 95% confidence interval (CI), 1.07-4.43] and African American race (OR =2.07; 95% CI, 1.22-3.51) were found to be the only two definitive independent risk factors for HCC in our sample. African American race and alcohol addiction were independent risk

  18. 76 FR 72619 - User Fee To Take the Registered Tax Return Preparer Competency Examination

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-25

    ..., 2011)), provide that only attorneys, certified public accountants, enrolled agents, and registered tax... Fee To Take the Registered Tax Return Preparer Competency Examination AGENCY: Internal Revenue Service... regulations. The final regulations redesignate rules pertaining to fees for obtaining a preparer tax...

  19. Exposure of hospital workers to airborne antineoplastic agents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    deWerk Neal, A.; Wadden, R.A.; Chiou, W.L.

    Practices for handling antineoplastic drugs were surveyed, and ambient-air sampling for four antineoplastic agents was conducted in outpatient oncology clinics. A questionnaire was administered in 1981 to the nurse or pharmacist in charge of drug preparation at 10 hospital oncology clinics. At three sites, air samples were collected during working hours in medication-preparation rooms and nearby offices. The air-sampling pumps contained filters at breathing-zone height; room air was drawn through each filter for 40 hours. Extracts from the filters were assayed by high-performance liquid chromatography (HPLC) for fluorouracil and cyclophosphamide in seven sets of samples and methotrexate and doxorubicin inmore » five sets of samples. Mass spectrometry (MS) was used to confirm detection of fluorouracil. Total use of each monitored drug was recorded at each site. Nine clinics had no ventilation hood, and drugs were prepared by nurses in eight clinics. Routine use of gloves (three clinics) and masks (one clinic) was uncommon, and wastes were disposed of in uncovered receptacles in four of the clinics. Eating and drinking occurred in seven of the preparation rooms. At the main air-sampling site, fluorouracil (0.12-82.26 ng/cu m) was detected in air during 200 of the 320 hours monitored. Cyclophosphamide (370 ng/cu m) was present during 80 hours. In the two other sites, fluorouracil was detected by HPLC but not confirmed by MS, and no cyclophosphamide was detected. No detectable amounts of methotrexate and doxorubicin were present. Fluorouracil was the most frequently used drug, and cyclophosphamide was second. Results suggest that personnel handling antineoplastic drugs are subject to potential systemic absorption of these agents by inhalation.« less

  20. History of chemical and biological warfare agents.

    PubMed

    Szinicz, L

    2005-10-30

    Chemical and biological warfare agents constitute a low-probability, but high-impact risk both to the military and to the civilian population. The use of hazardous materials of chemical or biological origin as weapons and for homicide has been documented since ancient times. The first use of chemicals in terms of weapons of mass destruction goes back to World War I, when on April 22, 1915 large amounts of chlorine were released by German military forces at Ypres, Belgium. Until around the 1970s of the 20th century, the awareness of the threat by chemical and biological agents had been mainly confined to the military sector. In the following time, the development of increasing range delivery systems by chemical and biological agents possessors sensitised public attention to the threat emanating from these agents. Their proliferation to the terrorists field during the 1990s with the expanding scale and globalisation of terrorist attacks suggested that these agents are becoming an increasing threat to the whole world community. The following article gives a condensed overview on the history of use and development of the more prominent chemical and biological warfare agents.

  1. Preparation and characterization of safe microparticles based on xylan.

    PubMed

    Cartaxo da Costa Urtiga, Silvana; Aquino Azevedo de Lucena Gabi, Camilla; Rodrigues de Araújo Eleamen, Giovanna; Santos Souza, Bartolomeu; Pessôa, Hilzeth de Luna Freire; Marcelino, Henrique Rodrigues; Afonso de Moura Mendonça, Elisângela; Egito, Eryvaldo Sócrates Tabosa do; Oliveira, Elquio Eleamen

    2017-10-01

    This work describes the preparation and evaluation of safe xylan-based microparticles prepared by cross-linking polymerization using sodium trimetaphosphate. The resulting microparticles were evaluated for morphology, particle size, polymer-cross-link agent interaction, and in vitro toxicity. The microparticles showed narrow monodisperse size distributions with their mean sizes being between 3.5 and 12.5 µm in dried state. FT-IR analyzes confirmed the interaction between sodium trimetaphosphate and xylan during the cross-linking process with formation of phosphate ester bonds. Additionally, the X-ray diffraction patterns and FT-IR analyzes suggested that little or no cross-linking agent remained inside the microparticles. Furthermore, the in-vitro studies using Artemia salina and human erythrocytes revealed that the microparticles are not toxic. Therefore, the overall results suggest that these xylan microparticles can be used as a platform for new drug delivery system.

  2. Preparation of small bio-compatible microspheres

    NASA Technical Reports Server (NTRS)

    Rembaum, Alan (Inventor); Yen, Shiao-Ping S. (Inventor); Dreyer, William J. (Inventor)

    1979-01-01

    Small, round, bio-compatible microspheres capable of covalently bonding proteins and having a uniform diameter below about 3500 A are prepared by substantially instantaneously initiating polymerization of an aqueous emulsion containing no more than 35% total monomer including an acrylic monomer substituted with a covalently bondable group such a hydroxyl, amino or carboxyl and a minor amount of a cross-linking agent.

  3. Preparation, characterization, and potential application of chitosan, chitosan derivatives, and chitosan metal nanoparticles in pharmaceutical drug delivery

    PubMed Central

    Ahmed, Tarek A; Aljaeid, Bader M

    2016-01-01

    Naturally occurring polymers, particularly of the polysaccharide type, have been used pharmaceutically for the delivery of a wide variety of therapeutic agents. Chitosan, the second abundant naturally occurring polysaccharide next to cellulose, is a biocompatible and biodegradable mucoadhesive polymer that has been extensively used in the preparation of micro-as well as nanoparticles. The prepared particles have been exploited as a potential carrier for different therapeutic agents such as peptides, proteins, vaccines, DNA, and drugs for parenteral and nonparenteral administration. Therapeutic agent-loaded chitosan micro- or nanoparticles were found to be more stable, permeable, and bioactive. In this review, we are highlighting the different methods of preparation and characterization of chitosan micro- and nanoparticles, while reviewing the pharmaceutical applications of these particles in drug delivery. Moreover, the roles of chitosan derivatives and chitosan metal nanoparticles in drug delivery have been illustrated. PMID:26869768

  4. Photoluminescence study of Mn doped ZnS nanoparticles prepared by co-precipitation method

    NASA Astrophysics Data System (ADS)

    Deshpande, M. P.; Patel, Kamakshi; Gujarati, Vivek P.; Chaki, S. H.

    2016-05-01

    ZnS nanoparticles co-doped with different concentration (5,10,15%) of Mn were synthesized using polyvinylpyrrolidone (PVP) as a capping agent under microwave irradiation. We confirmed doping of Mn in the host ZnS by EDAX whereas powder X-ray diffractogram showed the cubic zinc blende structure of all these samples. TEM images did showed agglomeration of particles and SAED pattern obtained indicated polycrystalline nature. From SAED pattern we calculated lattice parameter of the samples which have close resemblance from that obtained from XRD pattern. The band gap values of pure and doped ZnS nanoparticles were calculated from UV-Visible absorption spectra. ZnS itself is a luminescence material but when we dope it with transition metal ion such as Mn, Co, and Cu they exhibits strong and intense luminescence in the particular region. The photoluminescence spectra of pure ZnS nanoparticles showed an emission at 421 and 485nm which is blue emission which was originated from the defect sites of ZnS itself and also sulfur deficiency and when doped with Mn2+ an extra peak with high intensity was observed at 530nm which is nearly yellow-orange emission which isrelated to the presence of Mn in the host lattice.

  5. Preparation of Activated Carbon from Palm Shells Using KOH and ZnCl2 as the Activating Agent

    NASA Astrophysics Data System (ADS)

    Yuliusman; Nasruddin; Afdhol, M. K.; Amiliana, R. A.; Hanafi, A.

    2017-07-01

    Palm shell is a potential source of raw materials for the produce of activated carbon as biosorbent for quite large numbers. The purpose of this study is to produce activated carbon qualified Indonesian Industrial Standard (SNI), which will be used as biosorbent to purify the impurities in the off gas petroleum refinery products. Stages of manufacture of activated carbon include carbonization, activation of chemistry and physics. Carbonization of activated carbon is done at a temperature of 400°C followed by chemical activation with active agent KOH and ZnCl2. Then the physical activation is done by flowing N2 gas for 1 hour at 850°C and followed by gas flow through the CO2 for 1 hour at 850°C. Research results indicate that activation of the active agent KOH produce activated carbon is better than using the active agent ZnCl2. The use of KOH as an active agent to produce activated carbon with a water content of 13.6%, ash content of 9.4%, iodine number of 884 mg/g and a surface area of 1115 m2/g. While the use of ZnCl2 as the active agent to produce activated carbon with a water content of 14.5%, total ash content of 9.0%, iodine number 648 mg/g and a surface area of 743 m2/g.

  6. Preparation and Optical Properties of CuS Nanofilms by a Facile Two-Step Process

    NASA Astrophysics Data System (ADS)

    Cui, Zhankui; Zhou, Junqiang; Ge, Suxiang; Zhao, Hongxiao

    CuS nanofilms were prepared by a facile two-step process including chemical bath deposition of Cu nanofilms first and the subsequent thermal sulfuration step. The composition and structure of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and Raman spectroscopy. The optical properties of CuS nanofilms were determined by Ultraviolet-visible (UV-Vis) technique. The results show that the nanofilms composed by Cu spherical nanoparticles were completely transformed to the nanofilms composed by CuS nanosheets when the sulfuration temperature was 350∘C. The light absorption edges of CuS nanofilms exhibit red shift when sulfuration occurred at lower temperature. A plausible growth mechanism related with gas phase reaction for formation of CuS nanofilms was also proposed.

  7. RESISTANCE AND CROSS-RESISTANCE OF ESCHERICHIA COLI S MUTANTS TO THE RADIOMIMETIC AGENT PROFLAVINE

    PubMed Central

    Woody-Karrer, Pearl; Greenberg, Joseph

    1964-01-01

    Woody-Karrer, Pearl (Palo Alto Medical Research Foundation, Palo Alto, Calif.), and Joseph Greenberg. Resistance and cross-resistance of Escherichia coli S mutants to the radiomimetic agent proflavine. J. Bacteriol. 87:536–542. 1964.—All 50 of the first-step mutants of Escherichia coli S selected for resistance to proflavine were resistant to ultraviolet light and each of five different radiomimetic chemicals. The mutants were classified into eight types on the basis of their relative resistance to six different radiomimetic drugs and on the basis of the shape of their ultraviolet survival curves. Three of these types are identical to types previously isolated with other radiomimetic drugs; five of the types are new. A high proportion of the clones surviving proflavine treatment were phenotypically but not genetically resistant, and no strains were isolated which were resistant to proflavine but were not resistant to radiation. PMID:14129667

  8. Mössbauer study of novel iron(II) complexes synthesized with Schiff bases

    NASA Astrophysics Data System (ADS)

    Várhelyi, Cs.; Lengyel, A.; Homonnay, Z.; Szalay, R.; Pokol, Gy.; Szilágyi, I.-M.; Huszthy, P.; Papp, J.; Goga, F.; Golban, L.-M.; Várhelyi, M.; Tomoaia-Cotisel, M.; Szőke, Á.; Kuzmann, E.

    2017-11-01

    Novel [Fe(4-benzyl-2-hydroxyphenyl-propylidene)2ethylene-diamine], and [Fe (2,4,6-trihydroxy-benzyl-4-metoxiphenyl-methylidene)2ethylene-diamine] complexes were synthesized by reacting FeII salt with the indicated Schiff-base ligands. The compounds were characterized by57Fe Mössbauer spectroscopy, FTIR, UV-VIS, TG-DTA-DTG, MS, AFM, XRD, cyclic voltammetry and biological activity measurements. 295 K and 78 K Mössbauer spectra revealed that iron is dominantly in high spin FeII state in both complexes while simultaneously a minor low spin FeII was also present in both complexes, furthermore a minor high spin FeIII was observed in [Fe(2,4,6-trihydroxy-benzyl-4-metoxiphenyl- methylidene) 2ethylene-diamine], too.

  9. X-ray spatial frequency heterodyne imaging of protein-based nanobubble contrast agents

    PubMed Central

    Rand, Danielle; Uchida, Masaki; Douglas, Trevor; Rose-Petruck, Christoph

    2014-01-01

    Spatial Frequency Heterodyne Imaging (SFHI) is a novel x-ray scatter imaging technique that utilizes nanoparticle contrast agents. The enhanced sensitivity of this new technique relative to traditional absorption-based x-ray radiography makes it promising for applications in biomedical and materials imaging. Although previous studies on SFHI have utilized only metal nanoparticle contrast agents, we show that nanomaterials with a much lower electron density are also suitable. We prepared protein-based “nanobubble” contrast agents that are comprised of protein cage architectures filled with gas. Results show that these nanobubbles provide contrast in SFHI comparable to that of gold nanoparticles of similar size. PMID:25321797

  10. Superhydrophobic silica nanoparticles as ultrasound contrast agents.

    PubMed

    Jin, Qiaofeng; Lin, Chih-Yu; Kang, Shih-Tsung; Chang, Yuan-Chih; Zheng, Hairong; Yang, Chia-Min; Yeh, Chih-Kuang

    2017-05-01

    Microbubbles have been widely studied as ultrasound contrast agents for diagnosis and as drug/gene carriers for therapy. However, their size and stability (lifetime of 5-12min) limited their applications. The development of stable nanoscale ultrasound contrast agents would therefore benefit both. Generating bubbles persistently in situ would be one of the promising solutions to the problem of short lifetime. We hypothesized that bubbles could be generated in situ by providing stable air nuclei since it has been found that the interfacial nanobubbles on a hydrophobic surface have a much longer lifetime (orders of days). Mesoporous silica nanoparticles (MSNs) with large surface areas and different levels of hydrophobicity were prepared to test our hypothesis. It is clear that the superhydrophobic and porous nanoparticles exhibited a significant and strong contrast intensity compared with other nanoparticles. The bubbles generated from superhydrophobic nanoparticles sustained for at least 30min at a MI of 1.0, while lipid microbubble lasted for about 5min at the same settings. In summary MSNs have been transformed into reliable bubble precursors by making simple superhydrophobic modification, and made into a promising contrast agent with the potentials to serve as theranostic agents that are sensitive to ultrasound stimulation. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Adsorption study of a macro-RAFT agent onto SiO2-coated Gd2O3:Eu3+ nanorods: Requirements and limitations

    NASA Astrophysics Data System (ADS)

    Zou, Hua; Melro, Liliana; de Camargo Chaparro, Thaissa; de Souza Filho, Isnaldi Rodrigues; Ananias, Duarte; Bourgeat-Lami, Elodie; dos Santos, Amilton Martins; Barros-Timmons, Ana

    2017-02-01

    The use of a macromolecular RAFT (macro-RAFT) agent to encapsulate anisotropic nano-objects via emulsion polymerization is an emerging route to prepare polymer/inorganic colloidal nanocomposites. However, a number of requirements have to be fulfilled. This work aims at highlighting the effects of the preparative procedure and dispersion method on the amount of macro-RAFT agent adsorbed onto SiO2-coated Gd2O3:Eu3+ nanorods. The adsorption of macro-RAFT agent was studied using the depletion method with UV-vis spectrophotometry. Measurements were performed at a fixed concentration of nanorods and varying concentrations of the macro-RAFT agent in aqueous dispersion at room temperature. The adsorption isotherms showed that for the same initial macro-RAFT agent concentration, the highest adsorption capacity of the macro-RAFT agent on nanorods was usually achieved for non-calcined thin SiO2-coated nanorods under mild bath sonication.

  12. Stability of solutions of antineoplastic agents during preparation and storage for in vitro assays. General considerations, the nitrosoureas and alkylating agents.

    PubMed

    Bosanquet, A G

    1985-01-01

    In vitro drug sensitivity of tumour biopsies is currently being determined using a variety of methods. For these chemosensitivity assays many drugs are required at short notice, and this in turn means that the drugs must generally be stored in solution. There are, however, a number of potential problems associated with dissolving and storing drugs for in vitro use, which include (a) drug adsorption; (b) effects of freezing; (c) drug stability under the normal conditions of dilution and setting up of an in vitro assay; and (d) insolubility of drugs in normal saline (NS) or phosphate-buffered saline (PBS). These problems are considered in general, and some recommendations for use of solutions of drugs in in vitro assays are suggested. The nitrosoureas and alkylating agents are also investigated in greater detail in this respect. The nitrosoureas are found to be very labile in PBS at pH 7, with 5% degradation (t0.95) occurring in 10-50 min at room temperature. These values are increased about 10-fold on refrigeration and about 5- to 10-fold on reduction of the pH of the medium to pH 4-5. At pH 7 and room temperature, t0.95 is observed in under 1 h with the alkylating agents nitrogen mustard, chlorambucil, melphalan, 2,5-diaziridinyl-3,6-bis(2-hydroxyethylamino)-1,4-benzoquinone (BZQ), dibromodulcitol, dibromomannitol, treosulphan, and procarbazine. Of the other alkylating agents, 4-hydroperoxycylophosphamide (sometimes used in vitro in place of cyclophosphamide), busulphan, dianhydrogalactitol, aziridinylbenzoquinone (AZQ), and dacarbazine have a t0.95 of between 2 and 24 h, while ifosfamide and pentamethylmelamine are both stable in aqueous solution for greater than 7 days. About half the drugs studied in detail have been stored frozen in solution for in vitro use, although very little is known about their stability under these conditions.

  13. Contact Active Antimicrobial Coatings Prepared by Polymer Blending.

    PubMed

    Cuervo-Rodríguez, Rocío; López-Fabal, Fátima; Gómez-Garcés, José L; Muñoz-Bonilla, Alexandra; Fernández-García, Marta

    2017-11-01

    Herein, contact active antimicrobial films are prepared by simply blending cationic amphiphilic block copolymers with commercial polystyrene (PS). The copolymers are prepared by combining atom transfer radical polymerization and "click chemistry." A variety of copolymers are synthesized, and composed of a PS segment and an antimicrobial block bearing flexible side chain with thiazole and triazole groups, 4-(1-(2-(4-methylthiazol-5-yl)ethyl)-1H-1,2,3-triazol-4-yl) butyl methacrylate (TTBM). The length of the TTBM block is varied as well as the alkylating agent. Different films are prepared from N,N-dimethylformamide solution, containing variable PS-b-PTTBM/PS ratio: from 0 to 100 wt%. Remarkably, the blend films, especially those with 30 and 50 wt% of copolymers, exhibit excellent antimicrobial activities against Gram-positive, Gram-negative bacteria and fungi, even higher than films prepared exclusively from the cationic copolymers. Blends composed of 50 wt% of the copolymers present a more than 99.999% killing efficiency against the studied microorganisms. The better activity found in blends can be due to the higher roughness, which increases the surface area and consequently the contact with the microorganisms. These results demonstrate that the use of blends implies a reduction of the content of antimicrobial agent and also enhances the antimicrobial activity, providing new insights for the better designing of antimicrobial coatings. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. The preparation of steatite suspension for spray drying

    NASA Technical Reports Server (NTRS)

    Jirousek, L.; Spicak, K.

    1983-01-01

    Liquifying agents were investigated for preparation of highly concentrated steatite suspensions which are to be spray-dried. Organic additives for improving the molding properties and strength of green compacts are described. Demands on properties of the spray-dried granules are defined with regard to shrinkage of the molded compacts.

  15. Potassium Ferrate: A Novel Chemical Warfare Agent Decontaminant

    DTIC Science & Technology

    2004-11-16

    POTASSIUM FERRATE : A NOVEL CHEMICAL WARFARE AGENT DECONTAMINANT Russell Greene greener@battelle.org (Battelle Memorial Institute, West...difficulties, and/or unsatisfactory CWA destruction efficiencies. Potassium ferrate (K2FeO4) addresses all of these issues through its high oxidation...used and proposed, are unstable (with respect to loss of activity) and/or difficult to prepare, store and transport. Potassium ferrate (K2FeO4) has

  16. 76 FR 59329 - User Fees Relating to the Registered Tax Return Preparer Competency Examination and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ... and requiring tax return preparers who are not attorneys, certified public accountants, or enrolled... only attorneys, certified public accountants, enrolled agents, and registered tax return preparers are...-6 permits specified individuals who are supervised by the attorney, certified public accountant...

  17. Initial formal toxicity evaluation of APC-2, a novel fluorescent tracer agent for real-time measurement of glomerular filtration rate in preparation for a first-in-man clinical trial

    NASA Astrophysics Data System (ADS)

    Bugaj, Joseph E.; Dorshow, Richard B.

    2014-03-01

    The fluorescent tracer agent 2,5-bis[N-(1-carboxy-2-hydroxy)]carbamoyl-3,6-diaminopyrazine, designated APC-2, has been developed with properties and attributes necessary for use as a direct measure of glomerular filtration rate (GFR). Comparison to known standard exogenous GFR agents in animal models has demonstrated an excellent correlation. A clinical trial to demonstrate this same correlation in humans is in preparation. A battery of formal toxicity tests necessary for regulatory clearance to proceed with a clinical trial has been recently completed on this new fluorescent tracer agent. These include single dose toxicity studies in rats and dogs to determine overall toxicity and toxicokinetics of the compound. Blood compatibility, mutation assay, chromosomal aberration assay, and several other assays were also completed. Toxicity assessments were based on mortality, clinical signs, body weight, food consumption and anatomical pathology. Blood samples were collected to assess pharmacokinetic parameters including half-life, area under the curve, and clearance. Urine samples were collected to assess distribution. Doses of up to 200-300 times the estimated human dose were administered. No test-article related effects were noted on body weight, food consumption, ophthalmic observations and no abnormal pathology was seen in either macroscopic or microscopic evaluations of any organs or tissues. All animals survived to scheduled sacrifice. Transient discoloration of skin and urine was noted at the higher dose levels in both species as expected from a highly fluorescent compound and was not considered pathological. Thus initial toxicology studies of this new fluorescent tracer agent APC-2 have resulted in no demonstrable pathological test article concerns.

  18. Green Preparation of Epoxy/Graphene Oxide Nanocomposites Using a Glycidylamine Epoxy Resin as the Surface Modifier and Phase Transfer Agent of Graphene Oxide.

    PubMed

    Tang, Xinlei; Zhou, Yang; Peng, Mao

    2016-01-27

    In studies of epoxy/graphene oxide (GO) nanocomposites, organic solvents are commonly used to disperse GO, and vigorous mechanical processes and complicated modification of GO are usually required, increasing the cost and hindering the development and application of epoxy nanocomposites. Here, we report a green, facile, and efficient method of preparing epoxy/GO nanocomposites. When triglycidyl para-aminophenol (TGPAP), a commercially available glycidyl amine epoxy resin with one tertiary amine group per molecule, is used as both the surface modifier and phase transfer agent of GO, GO can be directly and rapidly transferred from water to diglycidyl ether of bisphenol A and other types of epoxy resins by manual stirring under ambient conditions, whereas GO cannot be transferred to these epoxy resins in the absence of TGPAP. The interaction between TGPAP and GO and the effect of the TGPAP content on the dispersion of GO in the epoxy matrix were investigated systematically. Superior dispersion and exfoliation of GO nanosheets and remarkably improved mechanical properties, including tensile and flexural properties, toughness, storage modulus, and microhardness, of the epoxy/GO nanocomposites with a suitable amount of TGPAP were demonstrated. This method is organic-solvent-free and technically feasible for large-scale preparation of high-performance nanocomposites; it opens up new opportunities for exploiting the unique properties of graphene or even other nanofillers for a wide range of applications.

  19. Potential therapeutic agents derived from the cannabinoid nucleus.

    PubMed

    Pars, H G; Howes, J F

    1977-01-01

    Drugs derived from Cannabis sativa (Cannabinceae) were used until the 1940's for their stimulant and depressant effects for treating somatic and psychiatric illnesses. Renewed interest in marihuana research began in the 1970's and again pointed to the therapeutic potential of cannabinoids. Safer and more useful therapeutic agents may be generated from cannabinoids similarly to morphine, lysergic acid diethylamide, and cocaine which have structurally related analgesics, oxytoxics, and local anesthetics respectively. It has been shown that the C-ring in cannabinoids can be substituted with a variety of nitrogen and sulfur-containing rings without loss of CNS (central nervous system) activity. Cannabinoids have been shown to inhibit prostaglandin synthesis, intensify pressor effects of endogenous amines like norepinephrine, and enhance the stimulant effects of amphetamine. Cannabinoids' therapeutic potential lies in the areas of analgesics and anticonvulsants, and for use as a sedative-hypnotic, an antiglaucoma agent, an antiasthmatic agent, an antidiarrheal agent, and possibly as an anticancer and immunosuppressant agent.

  20. Preparation of a Phosphor, ZnS:Cupric.

    ERIC Educational Resources Information Center

    Suib, Steven L.; Tanaka, John

    1984-01-01

    Background information (including optical properties of inorganic materials) and procedures are provided for an experiment which introduces students to preparation of a doped semiconductor; phosphorescence; gettering procedures; reducing atmospheres; and use of a high-temperature furnace with associated thermocouples, temperature controllers, and…

  1. 9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Procedures for preparing egg yolk... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic... chapter. (a) Under the supervision of an Authorized Agent or State Inspector, the eggs which are used in...

  2. Effect of complexing agent on the photoelectrochemical properties of bath deposited CdS thin films

    NASA Astrophysics Data System (ADS)

    Patil, S. B.; Singh, A. K.

    2010-02-01

    In the present paper photoelectrochemical (PEC) performance of bath deposited CdS thin films based on complexing agents i.e. ammonia and triethanolamine (TEA) has been discussed. Effect of annealing has also been analyzed. The as-deposited and annealed (at 523 K for 1 h in air) films were characterized by X-ray diffraction (XRD), ultraviolet-visible (UV-vis) absorption spectroscopy, SEM, electrochemical impedance spectroscopy (EIS), and PEC properties. XRD studies revealed that the films were nanocrystalline in nature with mixed hexagonal and cubic phases. TEA complex resulted in better crystallinity. Further improvement in the crystallinity of the films was observed after air annealing. The marigold flower-like structure, in addition to flakes morphology, was observed with TEA complex, whereas for ammonia complex only flakes morphology was observed. The UV-vis absorption studies revealed that the optical absorption edge for the films with ammonia and TEA complex was around 475 nm and 500 nm, respectively. Annealing of the films resulted in red shift in the UV-vis absorption. The PEC cell performance of CdS films was found to be strongly affected by crystallinity and morphology of the films resulted due to complexing agent and annealing. The air annealed film deposited using TEA complex showed maximum short circuit current density ( Jsc) and open circuit voltage ( Voc) i.e. 99 μA/cm 2 and 376 mV respectively, under 10 mW/cm 2 of illumination. The films deposited using TEA complex showed good stability under PEC cell conditions.

  3. CuIn(S,Se)(2) thin films prepared from a novel thioacetic acid-based solution and their photovoltaic application.

    PubMed

    Xie, Yian; Liu, Yufeng; Wang, Yaoming; Zhu, Xiaolong; Li, Aimin; Zhang, Lei; Qin, Mingsheng; Lü, Xujie; Huang, Fuqiang

    2014-04-28

    Low-cost and high-yield preparation of CuInSe2 films is the bottleneck for promising CuInSe2-based thin film solar cells. Here, we developed a simple, safe and cost-effective method using thioacetic acid to fabricate the absorber films of CuIn(S,Se)2 (CISSe). Dissolution of Cu2O and In(OH)3 in thioacetic acid was attributed to the strong coordination ability of S. The adhesive precursor solution can be prepared without any heating, centrifugation and inert gas protection, superior to the previously reported methods. The precursor CISSe layer was easily deposited in air by spin coating to ensure low cost. Uniform and compact CISSe thin films with well-crystallized and pure-phased CISSe grains were obtained after one step annealing. The as-prepared CISSe thin films were successfully applied to solar cells and a energy conversion efficiency of 6.75% was achieved. This facile preparation provides a low-cost and easy method to fabricate Cu-based thin film solar cells.

  4. Design, synthesis, and evaluation of VEGFR-targeted macromolecular MRI contrast agent based on biotin-avidin-specific binding.

    PubMed

    Liu, Yongjun; Wu, Xiaoyun; Sun, Xiaohe; Wang, Dan; Zhong, Ying; Jiang, Dandan; Wang, Tianqi; Yu, Dexin; Zhang, Na

    2017-01-01

    Developing magnetic resonance imaging (MRI) contrast agents with high relaxivity and specificity was essential to increase MRI diagnostic sensitivity and accuracy. In this study, the MRI contrast agent, vascular endothelial growth factor receptor (VEGFR)-targeted poly (l-lysine) (PLL)-diethylene triamine pentacetate acid (DTPA)-gadolinium (Gd) (VEGFR-targeted PLL-DTPA-Gd, VPDG), was designed and prepared to enhance the MRI diagnosis capacity of tumor. Biotin-PLL-DTPA-Gd was synthesized first, then, VEGFR antibody was linked to biotin-PLL-DTPA-Gd using biotin-avidin reaction. In vitro cytotoxicity study results showed that VPDG had low toxicity to MCF-7 cells and HepG2 cells at experimental concentrations. In cell uptake experiments, VPDG could significantly increase the internalization rates (61.75%±5.22%) in VEGFR-positive HepG2 cells compared to PLL-DTPA-Gd (PDG) (25.16%±4.71%, P <0.05). In MRI studies in vitro, significantly higher T1 relaxivity (14.184 mM -1 s -1 ) was observed compared to Magnevist ® (4.9 mM -1 s -1 ; P <0.01). Furthermore, in vivo MRI study results showed that VPDG could significantly enhance the tumor signal intensity and prolong the diagnostic time (from <1 h to 2.5 h). These results indicated that macromolecular VPDG was a promising MRI contrast agent and held great potential for molecular diagnosis of tumor.

  5. High longitudinal relaxivity of ultra-small gadolinium oxide prepared by microsecond laser ablation in diethylene glycol

    NASA Astrophysics Data System (ADS)

    Luo, Ningqi; Tian, Xiumei; Xiao, Jun; Hu, Wenyong; Yang, Chuan; Li, Li; Chen, Dihu

    2013-04-01

    Ultra-small gadolinium oxide (Gd2O3) can be used as T1-weighted Magnetic Resonance Imaging (MRI) contrast agent own to its high longitudinal relaxivity (r1) and has attracted intensive attention in these years. In this paper, ultra-small Gd2O3 nanoparticles of 3.8 nm in diameter have been successfully synthesized by a microsecond laser ablating a gadolinium (Gd) target in diethylene glycol (DEG). The growth inhibition effect induced by the large viscosity of DEG makes it possible to synthesize ultra-small Gd2O3 by laser ablation in DEG. The r1 value and T1-weighted MR images are measured by a 3.0 T MRI spectroscope. The results show these nanoparticles with a high r1 value of 9.76 s-1 mM-1 to be good MRI contrast agents. We propose an explanation for the high r1 value of ultra-small Gd2O3 by considering the decreasing factor (surface to volume ratio of the nanoparticles, S/V) and the increasing factor (water hydration number of the Gd3+ on Gd2O3 surface, q), which offer a new look into the relaxivity studies of MRI contrast agents. Our research provides a new approach to preparing ultra-small Gd2O3 of high r1 value by laser ablation in DEG and develops the understanding of high relaxivity of ultra-small Gd2O3 MRI contrast agents.

  6. Mother ship and physical agents collaboration

    NASA Astrophysics Data System (ADS)

    Young, Stuart H.; Budulas, Peter P.; Emmerman, Philip J.

    1999-07-01

    This paper discusses ongoing research at the U.S. Army Research Laboratory that investigates the feasibility of developing a collaboration architecture between small physical agents and a mother ship. This incudes the distribution of planning, perception, mobility, processing and communications requirements between the mother ship and the agents. Small physical agents of the future will be virtually everywhere on the battlefield of the 21st century. A mother ship that is coupled to a team of small collaborating physical agents (conducting tasks such as Reconnaissance, Surveillance, and Target Acquisition (RSTA); logistics; sentry; and communications relay) will be used to build a completely effective and mission capable intelligent system. The mother ship must have long-range mobility to deploy the small, highly maneuverable agents that will operate in urban environments and more localized areas, and act as a logistics base for the smaller agents. The mother ship also establishes a robust communications network between the agents and is the primary information disseminating and receiving point to the external world. Because of its global knowledge and processing power, the mother ship does the high-level control and planning for the collaborative physical agents. This high level control and interaction between the mother ship and its agents (including inter agent collaboration) will be software agent architecture based. The mother ship incorporates multi-resolution battlefield visualization and analysis technology, which aids in mission planning and sensor fusion.

  7. Optical X-ray density of composite resin luting agents.

    PubMed

    Carracho, Helena G; da Silveira, Ivori D; Soares, Clarissa G; Paranhos, Maria Paula G; Júnior, Luiz Henrique Burnett; Spohr, Ana Maria

    2011-01-01

    This study verified the optical density of four composite resin luting agents - RelyX ARC (RY), Enforce (E), C&B Cement (CB) and Flow it (FI), at thicknesses of 2, 3, and 4 mm. The optical density of the luting agents was compared with that of enamel and dentin at the same thicknesses. Fifteen tooth crowns were embedded in PVC cylinders with self-cured acrylic resin. In addition, acrylic resin was poured into 5 PVC cylinders and four equidistant 5 mm diameter holes were prepared, with one luting material inserted in each. A laboratory cutting machine was used to prepare 4-, 3- and 2-mm thick slices of the tooth crowns and materials. Digital images were obtained with a Digora system. Three radiographs of each thickness were obtained, totalizing 135 radiographs of the crowns and 45 of the materials. Three readings were carried out on each radiograph: three in enamel, three in dentin and three in each material, totalizing 1350. According to Students t-test (pagents E and FI can be distinguished from dental structures, while the CB and RY are not easily distinguished.

  8. As-prepared MoS2 quantum dot as a facile fluorescent probe for long-term tracing of live cells

    NASA Astrophysics Data System (ADS)

    Zhou, Kai; Zhang, Yue; Xia, Zhining; Wei, Weili

    2016-07-01

    Recently, the newly emerged two-dimensional nanomaterials, layered transition metal dichalcogenide (e.g. MoS2) nanosheets, have drawn tremendous attentions due to their extraordinary electronic and optical properties, and MoS2 quantum dots (MoS2 QDs) with lateral sizes less than 10 nm have been found to be highly luminescent. In the present study, a facile approach for large-scale preparation of MoS2 QDs by Na intercalation reaction without using any toxic organic reagents is proposed. MoS2 QDs were carefully characterized by various techniques including transmission electron microscopy, atomic force microscopy, dynamic light scattering, spectroscopy, in vitro cytotoxicology, and capillary electrophoresis. The as-prepared MoS2 QDs were strongly fluorescent, highly photo-stable, low in cytotoxicity, and readily reactive to thiols. These inherent properties of MoS2 QDs make them excellent fluorescent probes for long-term live cell tracing. The results of live cells imaging indicated that MoS2 QD stained cells remained highly fluorescent after long-term culture, and could be easily traced from other co-cultured cell lines.

  9. The kuru infectious agent is a unique geographic isolate distinct from Creutzfeldt–Jakob disease and scrapie agents

    PubMed Central

    Manuelidis, Laura; Chakrabarty, Trisha; Miyazawa, Kohtaro; Nduom, Nana-Aba; Emmerling, Kaitlin

    2009-01-01

    Human sporadic Creutzfeldt–Jakob disease (sCJD), endemic sheep scrapie, and epidemic bovine spongiform encephalopathy (BSE) are caused by a related group of infectious agents. The new U.K. BSE agent spread to many species, including humans, and clarifying the origin, specificity, virulence, and diversity of these agents is critical, particularly because infected humans do not develop disease for many years. As with viruses, transmissible spongiform encephalopathy (TSE) agents can adapt to new species and become more virulent yet maintain fundamentally unique and stable identities. To make agent differences manifest, one must keep the host genotype constant. Many TSE agents have revealed their independent identities in normal mice. We transmitted primate kuru, a TSE once epidemic in New Guinea, to mice expressing normal and ≈8-fold higher levels of murine prion protein (PrP). High levels of murine PrP did not prevent infection but instead shortened incubation time, as would be expected for a viral receptor. Sporadic CJD and BSE agents and representative scrapie agents were clearly different from kuru in incubation time, brain neuropathology, and lymphoreticular involvement. Many TSE agents can infect monotypic cultured GT1 cells, and unlike sporadic CJD isolates, kuru rapidly and stably infected these cells. The geographic independence of the kuru agent provides additional reasons to explore causal environmental pathogens in these infectious neurodegenerative diseases. PMID:19633190

  10. RGDS-conjugated CdSeTe/CdS quantum dots as near-infrared fluorescent probe: preparation, characterization and bioapplication

    NASA Astrophysics Data System (ADS)

    Li, Zhenzhen; Zhang, Qiyi; Huang, Huaying; Ren, Changjing; Pan, Yujin; Wang, Qing; Zhao, Qiang

    2016-12-01

    In the experiments, high-quality, water-soluble and near-infrared (NIR)-emitting CdSeTe and CdSeTe/CdS quantum dots (QDs) were successfully prepared. The average size of CdSeTe⁄CdS QDs was 7.68 nm and CdSeTe QDs was 4.33 nm. Arginine-glycine-aspartic-serine acid (RGDS) peptides were linked to CdSeTe/CdS QDs by N-(3-(dimethylamino)propyl)-N'-ehtylcarbodiimide hydrochloride (EDC) and N'-hydroxysuccinimide (NHS). The prepared RGDS-tagged NIR CdSeTe/CdS QDs (denoted as RGDS-CdSeTe/CdS) had an average diameter of 24.83 nm and were used for cancer cell immunofluorescence imaging. The characteristics of RGDS-conjugated CdSeTe/CdS such as morphology, structure, spectra, stability, cytotoxicity, and near-infrared microscopic imaging were investigated in detail. HepG2 cells were incubated with the novel fluorescent probe (RGDS-CdSeTe/CdS), which realized immunofluorescence targeting and imaging. The results reported here open up new perspectives for integrin-targeted near-infrared imaging and may aid in tumor detection including imaging-guided surgery.

  11. Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents

    DTIC Science & Technology

    2015-10-01

    This proposal aims to identify topically applied anti-inflammatory drugs that will reduce recipient site inflammation and skin graft contraction. We...hypothesize that the elevated and prolonged inflammatory state of the recipient wound bed is a causative factor in the development of skin graft contraction...Using a porcine model of skin graft contraction, we will screen for anti-inflammatory agents (dose, schedule of administration, drug class

  12. Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents

    DTIC Science & Technology

    2016-10-01

    inflammatory agents - Wound healing -Contraction ACCOMPLISHMENTS: What were the major goals of the project? Develop treatments that modulate...1 AD _____________________ (Leave blank) Award Number: W81XWH-14-2-0153 TITLE: Decreasing Skin Graft Contraction through Topical Wound Bed...TYPE Annual 3. DATES COVERED (From - To) 15 Sep 2015 - 14 Sep 2016 4. TITLE AND SUBTITLE Decreasing Skin Graft Contraction through Topical Wound Bed

  13. Antibacterial and remineralization effects of orthodontic bonding agents containing bioactive glass

    PubMed Central

    Kim, Dong-Hyun; Song, Chang Weon; Yoon, Seog-Young; Kim, Se-Yeon; Na, Hee Sam; Chung, Jin

    2018-01-01

    Objective The aim of this study was to evaluate the mechanical and biological properties of orthodontic bonding agents containing silver- or zinc-doped bioactive glass (BAG) and determine the antibacterial and remineralization effects of these agents. Methods BAG was synthesized using the alkali-mediated solgel method. Orthodontic bonding agents containing BAG were prepared by mixing BAG with flowable resin. Transbond™ XT (TXT) and Charmfil™ Flow (CF) were used as controls. Ion release, cytotoxicity, antibacterial properties, the shear bond strength, and the adhesive remnant index were evaluated. To assess the remineralization properties of BAG, micro-computed tomography was performed after pH cycling. Results The BAG-containing bonding agents showed no noticeable cytotoxicity and suppressed bacterial growth. When these bonding agents were used, demineralization after pH cycling began approximately 200 to 300 µm away from the bracket. On the other hand, when CF and TXT were used, all surfaces that were not covered by the adhesive were demineralized after pH cycling. Conclusions Our findings suggest that orthodontic bonding agents containing silver- or zinc-doped BAG have stronger antibacterial and remineralization effects compared with conventional orthodontic adhesives; thus, they are suitable for use in orthodontic practice. PMID:29732302

  14. Guidelines for Managing Suspected Chemical and Biological Agent Incidents in Rail Tunnel Systems

    DOT National Transportation Integrated Search

    2002-03-01

    These emergency management guidelines are designed to help transit managers (1) prepare and implement standard operating procedures (SOPs) for handling potential and actual chemical or biological agent attacks in their rail tunnel system and (2) unde...

  15. 21 CFR 173.357 - Materials used as fixing agents in the immobilization of enzyme preparations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... manufacture of high fructose corn syrup, in accordance with § 184.1372 of this chapter. Cellulose triacetate... glucose isomerase enzyme preparations for use in the manufacture of high fructose corn syrup, in... enzyme preparations for use in the manufacture of high fructose corn syrup, in accordance with § 184.1372...

  16. 21 CFR 173.357 - Materials used as fixing agents in the immobilization of enzyme preparations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... manufacture of high fructose corn syrup, in accordance with § 184.1372 of this chapter. Cellulose triacetate... glucose isomerase enzyme preparations for use in the manufacture of high fructose corn syrup, in... enzyme preparations for use in the manufacture of high fructose corn syrup, in accordance with § 184.1372...

  17. 21 CFR 173.357 - Materials used as fixing agents in the immobilization of enzyme preparations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... manufacture of high fructose corn syrup, in accordance with § 184.1372 of this chapter. Cellulose triacetate... glucose isomerase enzyme preparations for use in the manufacture of high fructose corn syrup, in... enzyme preparations for use in the manufacture of high fructose corn syrup, in accordance with § 184.1372...

  18. 21 CFR 173.357 - Materials used as fixing agents in the immobilization of enzyme preparations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... manufacture of high fructose corn syrup, in accordance with § 184.1372 of this chapter. Cellulose triacetate... glucose isomerase enzyme preparations for use in the manufacture of high fructose corn syrup, in... enzyme preparations for use in the manufacture of high fructose corn syrup, in accordance with § 184.1372...

  19. Preparation of Potential Radioprotective Agents Derived from Aminothiols

    DTIC Science & Technology

    1985-09-01

    H, 8.55 %; N, 4.25 %; S,19.43 % Found: C, 47.47%; H, 8.67%; N, 4.24%; S,19.43 % C. 2-MERCAPTOPHENOTHIAZINE 1. CoDDer29 Cupric sulfate pentahydrate ...extracts were collected and dried (anhydrous magnesium sulfate ). The solvent was removed by rotary evaporation at reduced pressure to 16 yield 5.28 g of a...extracted with three 50 mL portions of benzene. The combined benzene layers were washed with water, dried (magnesium sulfate ) and the solvent removed under

  20. Preparation and characterization of polystyrene/neodymium hydroxide (PS/Nd(OH)3) nano-composites

    NASA Astrophysics Data System (ADS)

    Alsewailem, Fares D.; Bagabas, Abdulaziz A.; Binkhodor, Yazeed A.

    2018-03-01

    Composites of polystyrene and Neodymium hydroxide nanrods (PS/Nd(OH)3) were formulated and characterized in this study. Cetyl (1-hexadccyl) trimethyl ammonium bromide (CTAB) was used as dispersion agent for the Nd(OH)3 rods in the PS matrix. PS/Nd(OH)3 composites were prepared by solution and melt compounding. Morphological, thermal, and mechanical properties of the prepared composites were investigated. CTAB was found to be more effective as dispersion agent in composites prepared by solution compounding in comparison with those prepared by melt compounding, and that was due to the mild conditions used in solution compounding. Nonetheless, impact strength of the composite at 0.5 wt% Nd(OH)3 was drastically reduced in the absence of CTAB. Both tensile and impact strengths were found to greatly decreased at higher loading of Nd(OH)3, e.g. 5 wt%, even with the use of CTAB. Thermal stability of the PS/Nd(OH)3 composites was noticeably increased at relatively low loading of Nd(OH)3, e.g. 0.5 wt%.

  1. Chemical Agents: Facts about Sheltering in Place

    MedlinePlus

    ... Populations Disaster Relief Volunteers Health Alert Network (HAN) Social Media Zombie Apocalypse What’s New Are You Prepared? Coping ... Groups Resources for Emergency Health Professionals Training & Education Social Media What’s New Preparation & Planning More on Preparedness What ...

  2. Model-Drive Architecture for Agent-Based Systems

    NASA Technical Reports Server (NTRS)

    Gradanin, Denis; Singh, H. Lally; Bohner, Shawn A.; Hinchey, Michael G.

    2004-01-01

    The Model Driven Architecture (MDA) approach uses a platform-independent model to define system functionality, or requirements, using some specification language. The requirements are then translated to a platform-specific model for implementation. An agent architecture based on the human cognitive model of planning, the Cognitive Agent Architecture (Cougaar) is selected for the implementation platform. The resulting Cougaar MDA prescribes certain kinds of models to be used, how those models may be prepared and the relationships of the different kinds of models. Using the existing Cougaar architecture, the level of application composition is elevated from individual components to domain level model specifications in order to generate software artifacts. The software artifacts generation is based on a metamodel. Each component maps to a UML structured component which is then converted into multiple artifacts: Cougaar/Java code, documentation, and test cases.

  3. Cinnamoylated chloroquine analogues: A new structural class of antimalarial agents.

    PubMed

    Gayam, Venkatareddy; Ravi, Subban

    2017-07-28

    A novel series of cinnamoylated chloroquine hybrid analogues were synthesized and evaluated as antimalarial agents. The trans cinnamic acid derivatives (3-8) were synthesized by utilizing substituted aldehydes and malanoic acid in DMF catalysed by DABCO. The final cinnamoylated chloroquine analogues (9-14) were synthesized by utilizing DCC coupling reagent. The amido chloroquine (17) was prepared from acid (16) and compound 2 in benzene using SOCl 2 as chlorinating agent. The corresponding ester (15) was prepared from 2-hydroxy acetophenone and 2-bromoacetates in actonitrile in presence of K 2 CO 3  as base followed by basic hydrolysis. The preparation of amide based chloroquine-chalcone analogues (18-22), were obtained by the combination of amido chloroquine (17) and aldehydes in 10% aq. KOH in methanol at room temperature. Further we prepared epichlorohydrin based chloroquine-chalcone analogues (25-28), by reacting the epoxide (24a, 24b and 24c) with 2 and methelenedioxy aniline. In vitro antimalarial activity against chloroquine sensitive strain 3D7, chloroquine resistant strain K1 of P. falciparum and in vitro cytotoxicity of compounds using VERO cell line was carried out. The synthesized molecules showed significant in vitro antimalarial activity especially against CQ resistant strain (K1). Among tested compounds, 13, 9 and 10 were found to be the most potent compounds of the series with IC 50 value of 44.06, 48.04 and 59.37 nM against chloroquine resistant K1 strain. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  4. Evaluation of New Cleanup Agents for Analysis of Pesticide Residues in Tea.

    PubMed

    Ueda, Yuko; Honda, Katsuhisa

    2017-01-01

    We evaluated the effectiveness of new cleanup agents (S-NH 2 and S-Si) compared with other previously reported cleanup agents (octadecylsilane, graphitized carbon, aminopropyl and silica gel) for removal of interfering substances such as catechin and caffeine prior to analysis of pesticide residues in tea. S-NH 2 and S-Si were highly efficient in removal of catechin and caffeine, respectively. Recoveries of 80 pesticides using S-NH 2 and S-Si were tested, and more than 70% of pesticides showed recovery greater than 70%. These results indicate that S-NH 2 and S-Si agents will be useful for analysis of pesticide residues in tea.

  5. Preparation of multifunctional polysaccharide microcontainers for lipophilic bioactive agents.

    PubMed

    Borodina, Tatiana N; Grigoriev, Dmitry O; Carillo, Maria A; Hartmann, Jürgen; Moehwald, Helmuth; Shchukin, Dmitry G

    2014-05-14

    Chitosan/xanthan gum microcontainers with a core-shell structure formed due to chemical interactions between polysaccharide chains induced by ultrasonication are presented. Containers were prepared by sonication of water-immiscible (oil-like) liquids in the solution of polysaccharides. One-step fabrication of the container permanent shell is possible, because of the contribution of ultrasonically caused formation of hydrogen bonds and amide linkages. We synthesized containers in a wide size range from 350 nm to 7500 nm, varying in oil/water ratio. The microcontainers were modified with oppositely charged polyelectrolytes and microparticles, which could be used to impart the specified properties to the system. The biocide 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one (DCOIT) was loaded into the proposed containers by utilizing its solution as an oil phase. The following incorporation of the DCOIT containers into the polymer coating demonstrated more sustained antimicrobial activity (∼30%) of the biocide in the encapsulated state, compared to its non-encapsulated form.

  6. One-step electrochemical deposition of a graphene-ZrO 2 nanocomposite: Preparation, characterization and application for detection of organophosphorus agents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Du, Dan; Liu, Juan; Zhang, Xiao-Yan

    2011-04-27

    This paper described the preparation, characterization, and electrochemical properties of a graphene-ZrO 2 nanocomposite (GZN) and its application for both the enrichment and detection of methyl parathion (MP). GZN was fabricated using electrochemical deposition and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), which showed the successful formation of nanocomposites. Due to the strong affinity to the phosphoric group and the fast electron-transfer kinetics of GZN, both the extraction and electrochemical detection of organophosphorus (OP) agents at the same GZN modified electrochemical sensor was possible. The combination of solid-phase extractionmore » and stripping voltammetric analysis allowed fast, sensitive, and selective determination of MP in garlic samples. The stripping response was highly linear over the MP concentrations ranging from 0.5 ng mL -1 to 100 ng mL -1, with a detection limit of 0.1 ng mL -1. This new nanocomposite-based electrochemical sensor provides an opportunity to develop a field-deployable, sensitive, and quantitative method for monitoring exposure to OPs.« less

  7. Effect of a bonding agent on in vitro biochemical activities of remineralizing resin-based calcium phosphate cements.

    PubMed

    Dickens, Sabine H; Flaim, Glenn M

    2008-09-01

    To test whether fluoride in a resin-based Ca-PO4 ion releasing cement or coating with an acidic bonding agent for improved adhesion compromised the cement remineralization potential. Cements were formulated without fluoride (Cement A) or with fluoride (Cement B). The treatment groups were A=Cement A; A2=Cement A+bonding agent; B=Cement B; B2=Cement B+bonding agent. The calcium, phosphate, and fluoride ion release in saliva-like solution (SLS) was determined from hardened cement disks without or with a coating of bonding agent. For the remineralization, two cavities were prepared in dentin of extracted human molars and demineralized. One cavity received composite resin (control); the other received treatment A, A2, B or B2. After 6 week incubation in SLS, 180 microm cross-sections were cut. The percentage remineralization was determined by transverse microradiography comparing the dentin mineral density under the cement to that under the control. The percentage of remineralization (mean+/-S.D.) was A (39+/-14)=B (37+/-18), A2 (23+/-13), B2 (14+/-7). Two-way analysis of variance (ANOVA) and Holm-Sidak test showed a significant effect from the presence of bonding agent (p<0.05), but not from fluoride (p>0.05). The ion solution concentrations of all groups showed undersaturation with respect to dicalcium phosphate dihydrate and calcium fluoride and supersaturation for fluorapatite and hydroxyapatite suggesting a positive remineralization potential. Compared to the control all treatments resulted in mineral increase. The remineralization was negatively affected by the presence of the bonding agent.

  8. A Study of Equity in Mathematics Education: Lessons from Japan for U.S. Teacher Preparation

    ERIC Educational Resources Information Center

    Furuto, Linda H. L.

    2015-01-01

    This study comes at an opportune moment for Japanese and U.S. educators, policymakers, and researchers given the trends of global policy and equity-based reform. Discussions of academic achievement in both societies allow us to examine accessibility in mathematics education in order to best prepare teachers to serve the needs of students.…

  9. CdS/ZnS nanocomposites: from mechanochemical synthesis to cytotoxicity issues.

    PubMed

    Baláž, Peter; Baláž, Matej; Dutková, Erika; Zorkovská, Anna; Kováč, Jaroslav; Hronec, Pavol; Kováč, Jaroslav; Čaplovičová, Mária; Mojžiš, Ján; Mojžišová, Gabriela; Eliyas, Alexander; Kostova, Nina G

    2016-01-01

    CdS/ZnS nanocomposites have been prepared by a two-step solid-state mechanochemical synthesis. CdS has been prepared from cadmium acetate and sodium sulfide precursors in the first step. The obtained cubic CdS (hawleyite, JCPDS 00-010-0454) was then mixed in the second step with the cubic ZnS (sphalerite, JCPDS 00-005-0566) synthesized mechanochemically from the analogous precursors. The crystallite sizes of the new type CdS/ZnS nanocomposite, calculated based on the XRD data, were 3-4 nm for both phases. The synthesized nanoparticles have been further characterized by high-resolution transmission electron microscopy (HRTEM) and micro-photoluminescence (μPL) spectroscopy. The PL emission peaks in the PL spectra are attributed to the recombination of holes/electrons in the nanocomposites occurring in depth associated with Cd, Zn vacancies and S interstitials. Their photocatalytic activity was also measured. In the photocatalytic activity tests to decolorize Methyl Orange dye aqueous solution, the process is faster and its effectivity is higher when using CdS/ZnS nanocomposite, compared to single phase CdS. Very low cytotoxic activity (high viability) of the cancer cell lines (selected as models of living cells) has been evidenced for CdS/ZnS in comparison with CdS alone. This fact is in a close relationship with Cd(II) ions dissolution tested in a physiological solution. The concentration of cadmium dissolved from CdS/ZnS nanocomposites with variable Cd:Zn ratio was 2.5-5.0 μg.mL(-1), whereas the concentration for pure CdS was much higher - 53 μg.ml(-1). The presence of ZnS in the nanocrystalline composite strongly reduced the release of cadmium into the physiological solution, which simulated the environment in the human body. The obtained CdS/ZnS quantum dots can serve as labeling media and co-agents in future anti-cancer drugs, because of their potential in theranostic applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Preparation of CNC-dispersed Fe3O4 nanoparticles and their application in conductive paper.

    PubMed

    Liu, Kai; Nasrallah, Joseph; Chen, Lihui; Huang, Liulian; Ni, Yonghao

    2015-08-01

    Well-dispersed Fe3O4 nanoparticles (NPs) were synthesized by a co-precipitation method in the presence of cellulose nano-crystals (CNC) as the template. The thus prepared Fe3O4 NPs were then used as a coating agent for the preparation of conductive paper. Fourier transform infrared spectroscopy (FTIR) results revealed that the Fe3O4 NPs were immobilized on the CNC through interactions between the hydroxyl groups of CNC and Fe3O4. Scanning transmission electron microscopy (STEM) images showed that the Fe3O4 NPs prepared in the presence of CNC can be dispersed in the CNC network, while the Fe3O4 NPs prepared in the absence of CNC tended to aggregate in aqueous solutions. The conductivity of the Fe3O4 NPs coated paper can reach to 0.0269 S/m at the coating amount of 14.75 g/m(2) Fe3O4/CNC nanocomposites. Therefore, the thus obtained coated paper can be potentially used as anti-static packaging material in the packaging field. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. A comparative study of the effects of Ag2S films prepared by MPD and HRTD methods on the performance of polymer solar cells

    NASA Astrophysics Data System (ADS)

    Zhai, Yong; Li, Fumin; Ling, Lanyun; Chen, Chong

    2016-10-01

    In this work, the Ag2S nanocrystalline thin films are deposited on ITO glass via molecular precursor decomposition (MPD) method and newly developed HRTD method for organic solar cells (ITO/Ag2S/P3HT:PCBM/MoO3/Au) as an electron selective layer and a light absorption material. The surface morphology, structure characterization, and optical property of the Ag2S films prepared by these two methods were compared and the effect of the prepared Ag2S film on the device performance is investigated. It is found that the Ag2S films prepared by HRTD method have lower roughness and better uniformity than the corresponding films prepared by the MPD method. In addition, a more effective and rapid transporting ability for the electrons and holes in the ITO/Ag2S(HRTD, n)/P3HT:PCBM/MoO3/Au cells is found, which reduces the charge recombination, and thus, improves the device performance. The highest efficiency of 3.21% achieved for the ITO/Ag2S(HRTD, 50)/P3HT:PCBM/MoO3/Au cell is 93% higher than that of the ITO/Ag2S(MPD, 2)/P3HT:PCBM/MoO3/Au cell.

  12. The formation of ReS(2) inorganic fullerene-like structures containing Re(4) parallelogram units and metal-metal bonds.

    PubMed

    Coleman, Karl S; Sloan, Jeremy; Hanson, Neal A; Brown, Gareth; Clancy, Gerald P; Terrones, Mauricio; Terrones, Humberto; Green, Malcolm L H

    2002-10-02

    The encapsulation of ReO(x) within ReS(2) inorganic fullerene-like cages is described for the first time. The encapsulate was prepared by the sulfidization of both hand-milled and ball-milled samples of ReO(2); partial conversion of the oxide to the sulfide was achieved with the degree of sulfidization depending on the exposure to the sulfidizing agent, H(2)S.

  13. Zirconium Hydroxide-coated Nanofiber Mats for Nerve Agent Decontamination.

    PubMed

    Kim, Sohee; Ying, Wu Bin; Jung, Hyunsook; Ryu, Sam Gon; Lee, Bumjae; Lee, Kyung Jin

    2017-03-16

    Diverse innovative fabrics with specific functionalities have been developed for requirements such as self-decontamination of chemical/biological pollutants and toxic nerve agents. In this work, Zr(OH) 4 -coated nylon-6,6 nanofiber mats were fabricated for the decontamination of nerve agents. Nylon-6,6 fabric was prepared via the electrospinning process, followed by coating with Zr(OH) 4 , which was obtained by the hydrolysis of Zr(OBu) 4 by a sol-gel reaction on nanofiber surfaces. The reaction conditions were optimized by varying the amounts of Zr(OBu) 4 ,the reaction time, and the temperature of the sol-gel reaction. The composite nanofibers show high decontamination efficiency against diisopropylfluorophosphate, which is a nerve agent analogue, due to its high nucleophilicity that aids in the catalysis of the hydrolysis of the phosphonate ester bonds. Composite nanofiber mats have a large potential and can be applied in specific fields such as military and medical markets. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Thermal migration of alloying agents in aluminium

    NASA Astrophysics Data System (ADS)

    Cooil, S. P.; Mørtsell, E. A.; Mazzola, F.; Jorge, M.; Wenner, S.; Edmonds, M. T.; Thomsen, L.; Klemm, H. W.; Peschel, G.; Fuhrich, A.; Prieto, M.; Schmidt, Th; Miwa, J. A.; Holmestad, R.; Wells, J. W.

    2016-11-01

    The in situ thermal migration of alloying agents in an Al-Mg-Si-Li alloy is studied using surface sensitive photo-electron and electron diffraction/imaging techniques. Starting with the preparation of an almost oxide free surface (oxide thickness = 0.1 nm), the relative abundance of alloying agents (Mg, Li and Si) at the surface are recorded at various stages of thermal annealing, from room temperature to melting (which is observed at 550 ◦C). Prior to annealing, the surface abundances are below the detection limit ≪1%, in agreement with their bulk concentrations of 0.423% Si, 0.322% Mg and 0.101% Li (atomic %). At elevated temperatures, all three alloying agents appear at drastically increased concentrations (13.3% Si, 19.7% Mg and 45.3% Li), but decrease again with further elevation of the annealing temperature or after melting. The temperature at which the migration occurs is species dependent, with Li migration occurring at significantly higher temperatures than Si and Mg. The mechanism of migration also appears to be species dependent with Li migration occurring all over the surface but Mg migration being restricted to grain boundaries.

  15. Quicker Q-Learning in Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Agogino, Adrian K.; Tumer, Kagan

    2005-01-01

    Multi-agent learning in Markov Decisions Problems is challenging because of the presence ot two credit assignment problems: 1) How to credit an action taken at time step t for rewards received at t' greater than t; and 2) How to credit an action taken by agent i considering the system reward is a function of the actions of all the agents. The first credit assignment problem is typically addressed with temporal difference methods such as Q-learning OK TD(lambda) The second credit assi,onment problem is typically addressed either by hand-crafting reward functions that assign proper credit to an agent, or by making certain independence assumptions about an agent's state-space and reward function. To address both credit assignment problems simultaneously, we propose the Q Updates with Immediate Counterfactual Rewards-learning (QUICR-learning) designed to improve both the convergence properties and performance of Q-learning in large multi-agent problems. Instead of assuming that an agent s value function can be made independent of other agents, this method suppresses the impact of other agents using counterfactual rewards. Results on multi-agent grid-world problems over multiple topologies show that QUICR-learning can achieve up to thirty fold improvements in performance over both conventional and local Q-learning in the largest tested systems.

  16. Proceedings of the Indo-U.S. bilateral workshop on accelerating botanicals/biologics agent development research for cancer chemoprevention, treatment, and survival

    PubMed Central

    B. Kumar, Nagi; Dhurandhar, Medha; Aggarwal, Bharat; Anant, Shrikant; Daniel, Kenyon; Deng, Gary; Djeu, Julie; Dou, Jinhui; Hawk, Ernest; Jayaram, B.; Jia, Libin; Joshi, Rajendra; Kararala, Madhuri; Karunagaran, Devarajan; Kucuk, Omer; Kumar, Lalit; Malafa, Mokenge; Samathanam, G. J.; Sarkar, Fazlul; Siddiqi, Maqsood; Singh, Rana P.; Srivastava, Anil; White, Jeffrey D.

    2013-01-01

    With the evolving evidence of the promise of botanicals/biologics for cancer chemoprevention and treatment, an Indo-U.S. collaborative Workshop focusing on “Accelerating Botanicals Agent Development Research for Cancer Chemoprevention and Treatment” was conducted at the Moffitt Cancer Center, 29–31 May 2012. Funded by the Indo-U.S. Science and Technology Forum, a joint initiative of Governments of India and the United States of America and the Moffitt Cancer Center, the overall goals of this workshop were to enhance the knowledge (agents, molecular targets, biomarkers, approaches, target populations, regulatory standards, priorities, resources) of a multinational, multidisciplinary team of researcher's to systematically accelerate the design, to conduct a successful clinical trials to evaluate botanicals/biologics for cancer chemoprevention and treatment, and to achieve efficient translation of these discoveries into the standards for clinical practice that will ultimately impact cancer morbidity and mortality. Expert panelists were drawn from a diverse group of stakeholders, representing the leadership from the National Cancer Institute's Office of Cancer Complementary and Alternative Medicine (OCCAM), NCI Experimental Therapeutics (NExT), Food and Drug Administration, national scientific leadership from India, and a distinguished group of population, basic and clinical scientists from the two countries, including leaders in bioinformatics, social sciences, and biostatisticians. At the end of the workshop, we established four Indo-U.S. working research collaborative teams focused on identifying and prioritizing agents targeting four cancers that are of priority to both countries. Presented are some of the key proceedings and future goals discussed in the proceedings of this workshop. PMID:24279005

  17. Proceedings of the Indo-U.S. bilateral workshop on accelerating botanicals/biologics agent development research for cancer chemoprevention, treatment, and survival.

    PubMed

    Kumar, Nagi B; Dhurandhar, Medha; Aggarwal, Bharat; Anant, Shrikant; Daniel, Kenyon; Deng, Gary; Djeu, Julie; Dou, Jinhui; Hawk, Ernest; Jayaram, B; Jia, Libin; Joshi, Rajendra; Kararala, Madhuri; Karunagaran, Devarajan; Kucuk, Omer; Kumar, Lalit; Malafa, Mokenge; Samathanam, G J; Sarkar, Fazlul; Siddiqi, Maqsood; Singh, Rana P; Srivastava, Anil; White, Jeffrey D

    2013-02-01

    With the evolving evidence of the promise of botanicals/biologics for cancer chemoprevention and treatment, an Indo-U.S. collaborative Workshop focusing on “Accelerating Botanicals Agent Development Research for Cancer Chemoprevention and Treatment” was conducted at the Moffitt Cancer Center, 29–31 May 2012. Funded by the Indo-U.S. Science and Technology Forum, a joint initiative of Governments of India and the United States of America and the Moffitt Cancer Center, the overall goals of this workshop were to enhance the knowledge (agents, molecular targets, biomarkers, approaches, target populations, regulatory standards, priorities, resources) of a multinational, multidisciplinary team of researcher's to systematically accelerate the design, to conduct a successful clinical trials to evaluate botanicals/biologics for cancer chemoprevention and treatment, and to achieve efficient translation of these discoveries into the standards for clinical practice that will ultimately impact cancer morbidity and mortality. Expert panelists were drawn from a diverse group of stakeholders, representing the leadership from the National Cancer Institute's Office of Cancer Complementary and Alternative Medicine (OCCAM), NCI Experimental Therapeutics (NExT), Food and Drug Administration, national scientific leadership from India, and a distinguished group of population, basic and clinical scientists from the two countries, including leaders in bioinformatics, social sciences, and biostatisticians. At the end of the workshop, we established four Indo-U.S. working research collaborative teams focused on identifying and prioritizing agents targeting four cancers that are of priority to both countries. Presented are some of the key proceedings and future goals discussed in the proceedings of this workshop.

  18. Urchin-like CdS/ZrO2 nanocomposite prepared by microwave-assisted hydrothermal combined with ion-exchange and its multimode photocatalytic activity

    NASA Astrophysics Data System (ADS)

    Li, Li; Wang, Lili; Zhang, Wenzhi; Zhang, Xiuli; Chen, Xi; Dong, Xue

    2014-12-01

    A series of urchin-like CdS/ZrO2 nanocomposites with different mole ratios of Cd/Zr were prepared by a two-step method combining the microwave-assisted hydrothermal and ion exchange methods. The products were characterized by X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and N2 adsorption-desorption measurements. The results of the study revealed that the CdS/ZrO2 nanocomposites had mixed phases of tetragonal ZrO2 and hexagonal CdS. Moreover, the samples prepared by the microwave-assisted hydrothermal method possessed the urchin-like structure with a surface composed of protrude-like nanoparticles in large quantities. The absorption in the visible region changed slightly with increasing mole ratio of Cd/Zr. Moreover, compared to the nanocomposites prepared by the conventional heating, the nanocomposites prepared by the microwave-assisted hydrothermal synthesis showed significantly different Brunauer-Emmett-Teller values, and the urchin-like CdS/ZrO2 structures were obtained. The photocatalytic degradation of methyl orange under ultraviolet (UV) light irradiation indicated that the photocatalytic activity of the CdS/ZrO2 nanocomposite with CdS/ZrO2 molar ratio of 30 % was higher than those of CdS, ZrO2, and other different ratios of CdS/ZrO2 nanocomposites. Moreover, under UV light, visible light, and microwave-assisted multimode photocatalytic degradation, the urchin-like CdS/ZrO2 nanocomposites significantly affected the photodegradation of various dyes. To understand the possible reaction mechanism of the photocatalysis by the CdS/ZrO2 nanocomposites, a series of controlled experiments were performed, and the stability and reusability of the CdS/ZrO2 nanocomposites were further investigated by the photocatalytic reaction.

  19. Surface impact on nanoparticle-based magnetic resonance imaging contrast agents

    PubMed Central

    Zhang, Weizhong; Liu, Lin; Chen, Hongmin; Hu, Kai; Delahunty, Ian; Gao, Shi; Xie, Jin

    2018-01-01

    Magnetic resonance imaging (MRI) is one of the most widely used diagnostic tools in the clinic. To improve imaging quality, MRI contrast agents, which can modulate local T1 and T2 relaxation times, are often injected prior to or during MRI scans. However, clinically used contrast agents, including Gd3+-based chelates and iron oxide nanoparticles (IONPs), afford mediocre contrast abilities. To address this issue, there has been extensive research on developing alternative MRI contrast agents with superior r1 and r2 relaxivities. These efforts are facilitated by the fast progress in nanotechnology, which allows for preparation of magnetic nanoparticles (NPs) with varied size, shape, crystallinity, and composition. Studies suggest that surface coatings can also largely affect T1 and T2 relaxations and can be tailored in favor of a high r1 or r2. However, the surface impact of NPs has been less emphasized. Herein, we review recent progress on developing NP-based T1 and T2 contrast agents, with a focus on the surface impact. PMID:29721097

  20. What's New in Teacher Preparation?

    ERIC Educational Resources Information Center

    Phi Delta Kappan, 2013

    2013-01-01

    Teacher educators have not been sitting quietly by the side as others have demanded changes in teacher preparation programs. Across the nation, scores of efforts are underway to recruit, train, induct, and retain a highly skilled class of professionals for American schools. The stories presented in this article cover just a fraction of the…

  1. The Fe(III) and Ga(III) coordination chemistry of 3-(1-hydroxymethylidene) and 3-(1-hydroxydecylidene)-5-(2-hydroxyethyl)pyrrolidine-2,4-dione: Novel tetramic acid degradation products of homoserine lactone bacterial quorum sensing molecules

    PubMed Central

    Romano, Ariel A.; Hahn, Tobias; Davis, Nicole; Lowery, Colin A.; Struss, Anjali K.; Janda, Kim D.; Böttger, Lars H.; Matzanke, Berthold F.; Carrano, Carl J.

    2011-01-01

    Bacteria use small diffusible molecules to exchange information in a process called quorum sensing (QS). An important class of quorum sensing molecules used by Gram-negative bacteria is the family of N-acylhomoserine lactones (HSL). It was recently discovered that a degradation product of the QS molecule 3-oxo-C12-homoserine lactone, the tetramic acid 3-(1-hydroxydecylidene)-5-(2-hydroxyethyl)pyrrolidine-2,4-dione, is a potent antibacterial agent, thus implying roles for QS outside of simply communication. Because these tetramic acids also appear to bind iron with appreciable affinity it was suggested that metal binding might contribute to their biological activity. Here, using a variety of spectroscopic tools, we describe the coordination chemistry of both the methylidene and decylidene tetramic acid derivatives with Fe(III) and Ga(III) and discuss the potential biological significance of such metal binding. PMID:22178671

  2. Preparation and recrystallization behavior of spray-dried co-amorphous naproxen-indomethacin.

    PubMed

    Beyer, Andreas; Radi, Lydia; Grohganz, Holger; Löbmann, Korbinian; Rades, Thomas; Leopold, Claudia S

    2016-07-01

    To improve the dissolution properties and the physical stability of amorphous active pharmaceutical ingredients, small molecule stabilizing agents may be added to prepare co-amorphous systems. The objective of the study was to investigate if spray-drying allows the preparation of co-amorphous drug-drug systems such as naproxen-indomethacin and to examine the influence of the process conditions on the resulting initial sample crystallinity and the recrystallization behavior of the drug(s). For this purpose, the process parameters inlet temperature and pump feed rate were varied according to a 2(2) factorial design and the obtained samples were analyzed with X-ray powder diffractometry and Fourier-transformed infrared spectroscopy. Evaluation of the data revealed that the preparation of fully amorphous samples could be achieved depending on the process conditions. The resulting recrystallization behavior of the samples, such as the total recrystallization rate, the individual recrystallization rates of naproxen and indomethacin as well as the polymorphic form of indomethacin that was formed were influenced by these process conditions. For initially amorphous samples, it was found that naproxen and indomethacin recrystallized almost simultaneously, which supports the theory of formation of drug-drug heterodimers in the co-amorphous phase. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Hydrophilic nano-silica coating agents with platinum and diamond nanoparticles for denture base materials.

    PubMed

    Yoshizaki, Taro; Akiba, Norihisa; Inokoshi, Masanao; Shimada, Masayuki; Minakuchi, Shunsuke

    2017-05-31

    Preventing microorganisms from adhering to the denture surface is important for ensuring the systemic health of elderly denture wearers. Silica coating agents provide high hydrophilicity but lack durability. This study investigated solutions to improve the durability of the coating layer, determine an appropriate solid content concentration of SiO 2 in the silica coating agent, and evaluate the effect of adding platinum (Pt) and diamond nanoparticles (ND) to the agent. Five coating agents were prepared with different SiO 2 concentrations with/without Pt and ND additives. The contact angle was measured, and the brush-wear test was performed. Scanning electron microscopy was used to investigate the silica coating layer. The appropriate concentration of SiO 2 was found to be 0.5-0.75 wt%. The coating agents with additives showed significantly high hydrophilicity immediately after coating and after the brush-wear test. The coating agents with/without additives formed a durable coating layer even after the brush-wear test.

  4. Autonomous microfluidic sample preparation system for protein profile-based detection of aerosolized bacterial cells and spores.

    PubMed

    Stachowiak, Jeanne C; Shugard, Erin E; Mosier, Bruce P; Renzi, Ronald F; Caton, Pamela F; Ferko, Scott M; Van de Vreugde, James L; Yee, Daniel D; Haroldsen, Brent L; VanderNoot, Victoria A

    2007-08-01

    For domestic and military security, an autonomous system capable of continuously monitoring for airborne biothreat agents is necessary. At present, no system meets the requirements for size, speed, sensitivity, and selectivity to warn against and lead to the prevention of infection in field settings. We present a fully automated system for the detection of aerosolized bacterial biothreat agents such as Bacillus subtilis (surrogate for Bacillus anthracis) based on protein profiling by chip gel electrophoresis coupled with a microfluidic sample preparation system. Protein profiling has previously been demonstrated to differentiate between bacterial organisms. With the goal of reducing response time, multiple microfluidic component modules, including aerosol collection via a commercially available collector, concentration, thermochemical lysis, size exclusion chromatography, fluorescent labeling, and chip gel electrophoresis were integrated together to create an autonomous collection/sample preparation/analysis system. The cycle time for sample preparation was approximately 5 min, while total cycle time, including chip gel electrophoresis, was approximately 10 min. Sensitivity of the coupled system for the detection of B. subtilis spores was 16 agent-containing particles per liter of air, based on samples that were prepared to simulate those collected by wetted cyclone aerosol collector of approximately 80% efficiency operating for 7 min.

  5. Studies in Multifunctional Drug Development: Preparation and Evaluation of 11beta-Substituted Estradiol-Drug Conjugates, Cell Membrane Targeting Imaging Agents, and Target Multifunctional Nanoparticles

    NASA Astrophysics Data System (ADS)

    Dao, KinhLuan Lenny D.

    Cancer is the second leading cause of death after cardiovascular disease in the United State. Despite extensive research in development of antitumor drugs, most of these therapeutic entities often possess nonspecific toxicity, thus they can only be used to treat tumors in higher doses or more frequently. Because of the cytotoxicity and severe side effects, the drug therapeutic window normally is limited. Beside the toxicity issue, antitumor drug are also not selectively taken up by tumor cells, thus the necessitating concentrations that would eradicate the tumor can often not be used. In addition, tumor cells tend to develop resistance against the anticancer drugs after prolonged treatment. Therefore, alleviating the systemic cytotoxicity and side effects, improving in tumor selectivity, high potency, and therapeutic efficacy are still major obstacles in the area of anticancer drug development. A more promising approach for developing a selective agent for cancer is to conjugate a potent therapeutic drug, or an imaging agent with a targeting group, such as antibody or a high binding-specificity small molecule, that selectively recognize the overexpressed antigens or proteins on tumor cells. My research combines several approaches to describe this strategy via using different targeting molecules to different diseases, as well as different potent cytotoxic drugs for different therapies. Three studies related to the preparation and biological evaluation of new therapeutic agents, such as estradiol-drug hybrids, cell membrane targeted molecular imaging agents, and multifunctional NPs will be discussed. The preliminary results of these studies indicated that our new reagents achieved their initial objectives and can be further improved for optimized synthesis and in vivo experiments. The first study describes the method in which we employed a modular assembly approach to synthesize a novel 11beta-substituted steroidal anti-estrogen. The key intermediate was synthesized

  6. Innovation and the Evolving System of U.S. Teacher Preparation

    ERIC Educational Resources Information Center

    Wilson, Suzanne M.

    2014-01-01

    A longstanding tradition criticizes education schools for their presumed vapid curriculum, out-of-touch faculty, irrelevance, and suffocating ideology. What is different at present is the enthusiasm for alternatives to university-based teacher preparation, as well as the increasing interest in holding teacher preparation programs accountable. I…

  7. Preparation and Evaluation of Ribonuclease-Resistant Viral HIV RNA Standards Based on Armored RNA Technology

    PubMed

    Gholami, Mohammad; Ravanshad, Mehrdad; Baesi, Kazem; Samiee, Siamak M.; Hosseini Rozbahani, Negin; Mohraz, Minoo

    2018-05-19

    The human immunodeficiency virus type 1 (HIV-1) is an infectious viral agent that gradually extinguishes the immune system, resulting in acquired immune deficiency syndrome (AIDS). The aim of this study was to construct an RNA-positive control based on armored (AR) RNA technology, using HIV-1 RNA as a model. The MS2 maturase, a coat protein gene (at positions 1765 to 1787) and HIV-1 pol gene were cloned into pET-32a plasmid. The prepared plasmid was transformed into Escherichia coli strain BL2 (DE3), and the expression of the construct was induced by 1 mM of isopropyl-L-thio-D-galactopyranoside (IPTG) at 37 °C for 16 h to obtain the fabricated AR RNA. The AR RNA was precipitated and purified using polyethylene glycol and Sephacryl S-200 chromatography. The stability of AR RNA was evaluated by treatment with DNase I and RNase A and confirmed by transmission electron microscopy and gel agarose electrophoresis. Tenfold serial dilution of AR RNA from 101 to 105 was prepared; real-time PCR assays had a range of detection between 101 and 105, R2 value was 0.998, and the slope of the standard curve was -3.33. Prepared AR RNA, as a positive control, could be used as a basis for launching an in-house HIV-1 virus assay and other infectious agents. It can be readily available to laboratories and HIV research centers. The AR RNA is non-infectious and highly resistant to ribonuclease enzyme and can reduce the risk of infection in the clinical laboratory.

  8. Preparation and validation of gross alpha/beta samples used in EML`s quality assessment program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scarpitta, S.C.

    1997-10-01

    A set of water and filter samples have been incorporated into the existing Environmental Measurements Laboratory`s (EML) Quality Assessment Program (QAP) for gross alpha/beta determinations by participating DOE laboratories. The participating laboratories are evaluated by comparing their results with the EML value. The preferred EML method for measuring water and filter samples, described in this report, uses gas flow proportional counters with 2 in. detectors. Procedures for sample preparation, quality control and instrument calibration are presented. Liquid scintillation (LS) counting is an alternative technique that is suitable for quantifying both the alpha ({sup 241}Am, {sup 230}Th and {sup 238}Pu) andmore » beta ({sup 90}Sr/{sup 90}Y) activity concentrations in the solutions used to prepare the QAP water and air filter samples. Three LS counting techniques (Cerenkov, dual dpm and full spectrum analysis) are compared. These techniques may be used to validate the activity concentrations of each component in the alpha/beta solution before the QAP samples are actually prepared.« less

  9. Factors Contributing to the Preference of Korean Patients with Crohn’s Disease When Selecting an Anti-Tumor Necrosis Factor Agent (CHOICE Study)

    PubMed Central

    Kim, Eun Soo; Kim, Kyeong Ok; Jang, Byung Ik; Lee, Chang Kyun; Kim, Hyo Jong; Lee, Kang-Moon; Kim, You Sun; Eun, Chang Soo; Jung, Sung-Ae; Yang, Suk-Kyun; Lee, Jun; Kim, Tae-Oh; Jung, Yunho; Seo, Geom Seog; Yoon, Soon Man

    2016-01-01

    Background/Aims Two comparable anti-tumor necrosis factor (TNF) agents with different routes of administration (intravenous [iv] infliximab [IFX] vs subcutaneous [sc] adalimumab [ADA]) are available for patients with Crohn’s disease (CD) in Korea. This study aimed to identify the preferences of Korean CD patients for a specific anti-TNF agent and the factors contributing to the decision. Methods A prospective survey was performed among anti-TNF-naive CD patients in 10 tertiary referral hospitals. A 16-item questionnaire addressed patient preferences and the factors contributing to the decision in favor of a particular anti-TNF agent. A logistic regression was conducted to assess predictive factors for ADA preference. Results Overall, 189 patients (139 males; mean age, 32.47±11.71 years) completed the questionnaire. IFX and ADA were preferred by 63.5% (120/189) and 36.5% (69/189) of patients, respectively. The most influential reason for choosing IFX was ‘doctor’s presence’ (68.3%, 82/120), and ADA was “easy to use” (34.8%, 24/69). Amid various clinicodemographic data, having a >60-minute travel time to the hospital was a significant independent predictive factor for ADA preference. Conclusions A large number of anti-TNF-naive Korean patients with CD preferred anti-TNFs with an iv route of administration. The reassuring effect of a doctor’s presence might be the main contributing factor for this decision. PMID:26347512

  10. Cushing’s Syndrome: All variants, detection, and treatment

    PubMed Central

    Sharma, Susmeeta T.; Nieman, Lynnette K.

    2010-01-01

    Synopsis Cushing’s syndrome is caused by prolonged exposure to excess glucocorticoids. Diagnosis of Cushing’s syndrome involves a step-wise approach and establishing the cause can be challenging in some cases. Hypertension is present in about 80% of patients with Cushing’s syndrome and can lead to significant morbidity and mortality. Several pathogenic mechanisms have been proposed for glucocorticoid-induced hypertension including a functional mineralocorticoid excess state, up-regulation of the renin angiotensin system and deleterious effects of cortisol on the vasculature. Surgical excision of the cause of excess glucocorticoids remains the optimal treatment for Cushing’s syndrome. Anti-glucocorticoid and antihypertensive agents and steroidogenesis inhibitors can be used as adjunctive treatment modalities in preparation for surgery, and in cases where surgery is contraindicated or has not led to cure. PMID:21565673

  11. Facile synthesis and biological evaluation of novel symmetrical biphenyls as antitumor agents.

    PubMed

    Zhang, Jie; Zhang, Yanmin; Pan, Xiaoyan; Wang, Chen; Hu, Zhigang; Wang, Sicen; He, Langchong

    2012-03-01

    As a continuation to our previous work in developing anticancer agents, eighteen symmetrical biphenyl derivatives structurally related to taspine were synthesized and evaluated in vitro and in vivo. All the compounds were prepared with varied substitutions in the phenyl ring of aniline moiety. The cytotoxicity and anticancer activity of biphenyls was evaluated against various human tumor and normal cell line. Antiproliferative assays indicated that some of them exhibited potent anticancer activity. The potent antiproliferative activity of these compounds against ECV304 suggested that these biphenyls could be served as antiangiogenic agents. The highly active compound (2) also exhibited potent growth inhibition against cancer cell lines in vivo. Our findings demonstrated that these symmetrical biphenyl derivatives would be a promising candidate as novel anticancer agents.

  12. Comparative Evaluation of Firefighting Foam Agents

    DTIC Science & Technology

    1979-08-01

    incorporating these basic concepts under a military specification, are being produced on a world-wide MIL - F - 24385 , Navy (reference 6). basis. The original...Program Office for 24385 (Navy), Fire Extinguishing Aircraft Ground Fire Suppression and Agent, Aqueous- F Ilm-Forming-Foam Rescue, SMF, AGFSkS 71-1...fluoroprotein foams (FPF), and three protein foam (?’ F ) agents. Large-scale fire tests were performed under fixed fire conditions employing air

  13. Decontamination of biological warfare agents by a microwave plasma torch

    NASA Astrophysics Data System (ADS)

    Lai, Wilson; Lai, Henry; Kuo, Spencer P.; Tarasenko, Olga; Levon, Kalle

    2005-02-01

    A portable arc-seeded microwave plasma torch running stably with airflow is described and applied for the decontamination of biological warfare agents. Emission spectroscopy of the plasma torch indicated that this torch produced an abundance of reactive atomic oxygen that could effectively oxidize biological agents. Bacillus cereus was chosen as a simulant of Bacillus anthracis spores for biological agent in the decontamination experiments. Decontamination was performed with the airflow rate of 0.393l/s, corresponding to a maximum concentration of atomic oxygen produced by the torch. The experimental results showed that all spores were killed in less than 8 s at 3 cm distance, 12 s at 4 cm distance, and 16 s at 5 cm distance away from the nozzle of the torch.

  14. Cusp Fracture Resistance of Maxillary Premolars Restored with the Bonded Amalgam Technique Using Various Luting Agents

    PubMed Central

    Marchan, Shivaughn M.; Coldero, Larry; White, Daniel; Smith, William A. J.; Rafeek, Reisha N.

    2009-01-01

    Objective. This in vitro study uses measurements of fracture resistance to compare maxillary premolars restored with the bonded amalgam technique using a new resin luting cement, glass ionomer, and resin-modified glass ionomer as the bonding agents. Materials. Eighty-five sound maxillary premolars were selected and randomly assigned to one of five test groups of 17 teeth each. One group of intact teeth served as the control. The remaining groups were prepared to a standard cavity form relative to the dimensions of the overall tooth and restored with amalgam alone or a bonded amalgam using one of three luting agents: RelyX Arc (a new resin luting cement), RelyX luting (a resin-modified glass ionomer), or Ketac-Cem μ (a glass ionomer) as the bonding agents. Each tooth was then subjected to compressive testing until catastrophic failure occurred. The mean loads at failure of each group were statistically compared using ANOVA with a post hoc Bonferroni test. Results. It was found that regardless of the luting cement used for the amalgam bonding technique, there was little effect on the fracture resistance of teeth. Conclusion. Cusp fracture resistance of premolars prepared with conservative MOD cavity preparations is not improved by using an amalgam-bonding technique compared to similar cavities restored with amalgam alone. PMID:20339450

  15. Quality aspects of fibrinolytic agents based on biochemical characterization.

    PubMed

    Werner, R G; Bassarab, S; Hoffmann, H; Schlüter, M

    1991-11-01

    The purity, composition and in vitro fibrinolytic activity of four commercially available fibrinolytic agents, alteplase (recombinant tissue plasminogen activator, rt-PA, Actilyse; CAS 105857-23-6), streptokinase, urokinase and anistreplase (ansioyl-plasminogen-streptokinase activator-complex, APSAC), have been compared in this investigation. The fibrinolytic activity was measured in an in vitro thrombolytic assay. In this assay a human blood thrombus is dissolved in an environment of human plasma. This assay is representative for the in vivo situation, where plasminogen activation is also a limiting step in thrombolysis. In the in vitro thrombolytic assay alteplase is about 10 times more effective in clot lysis than either streptokinase or urokinase and more than 300 times more active than anistreplase. In addition, the ratio of active ingredient to total protein content in the preparations was analysed by RP-HPLC, SDS-PAGE, GPC-HPLC and amino acid analysis. The portion of active ingredient per total protein was 99.9% for alteplase, 55% for anistreplase, 20% for urokinase and 1% for streptokinase. This demonstrates that alteplase is the only fibrinolytic agent tested which is essentially free of protein additives of human origine and potential contaminants associated therewith. The superior purity of alteplase compared to the other fibrinolytics was confirmed by SDS-PAGE, RP-HPLC, and HPLC-GPC. Significant levels of aggregates were detected in streptokinase and urokinase preparations, whereas alteplase and anistreplase were essentially free of aggregates. These data demonstrate that there are significant differences in composition, purity and in vitro activity between different fibrinolytic agents.

  16. Preparation and characterization of poly (arylene ether isoxazole)s by fluoride ion-mediated aromatic nucleophilic displacement reactions

    NASA Technical Reports Server (NTRS)

    Herbert, C. G.; Bass, R. G.

    1994-01-01

    As part of a continuing effort to prepare novel thermally stable high-performance polymers, poly(arylene ether isoxazole)s have been prepared by fluoride ion-catalyzed aromatic nucleophilic substitution reactions with bis(trimethylsiloxyphenyl) isoxazoles and activated bisarylhalides in diphenyl sulfone. Initial investigation involving the preparation of these materials with isoxazole bisphenols and activated bisarylhalides in the presence of potassium carbonate indicated that, under reaction conditions necessary to prepare high-molecular-weight materials, the isoxazole monomer was converted to an enamino ketone. This side reaction was avoided by using fluoride as a base. However, trimethylsilyl ether derivatives of the isoxazole bisphenols were required in these polymerizations for the preparation of high-molecular-weight materials. Moderate to high inherent viscosity eta(sub inh): 0.43-0.87 dl/g) materials with good thermal stability (air: 409-477 C, helium: 435-512 C) can be prepared by the silyl ether method. Glass transition temperatures ranged from 182 to 225 C for polymers with phenyl pendants and from 170 to 214 C for those without. Molecular weight control by 2% endcapping and the incorporation of a phenyl pendant at the 4 position of the isoxazole is necessary to yield polymers soluble in polar aprotic solvents at room temperature. There is evidence, however, indicating the existence of crosslinks between the polymer chains when the silyl ether approach is utilized.

  17. Assessing Public Issues Knowledge and Needs of Extension Agents in Florida

    ERIC Educational Resources Information Center

    Gay, Keegan D.; Owens, Courtney T.; Lamm, Alexa J.; Rumble, Joy N.

    2017-01-01

    It has been argued that to remain relevant in today's society, Extension must expand its role to provide public issues education. We conducted a web-based survey to determine whether Extension agents in Florida were prepared to deal with contentious issues. Survey respondents identified issues affecting their clientele, levels of frequency with…

  18. Blood Ammonia as a Possible Etiological Agent for Alzheimer’s Disease

    PubMed Central

    Jin, Yan Yan; Singh, Parul; Chung, Hea-Jong; Hong, Seong-Tschool

    2018-01-01

    Alzheimer’s disease (AD), characterized by cognitive decline and devastating neurodegeneration, is the most common age-related dementia. Since AD is a typical example of a complex disease that is affected by various genetic and environmental factors, various factors could be involved in preventing and/or treating AD. Extracellular accumulation of beta-amyloid peptide (Aβ) and intracellular accumulation of tau undeniably play essential roles in the etiology of AD. However, interestingly enough, medications targeting Aβ or tau all failed and the only clinically efficient medications for AD are drugs targeting the cholinergic pathway. Also, a very intriguing discovery in AD is that the Mediterranean diet (MeDi), containing an unusually large quantity of Lactobacilli, is very effective in preventing AD. Based on recently emerging findings, it is our opinion that the reduction of blood ammonia levels by Lactobacilli in MeDi is the therapeutic agent of MeDi for AD. The recent evidence of Lactobacilli lowering blood ammonia level not only provides a link between AD and MeDi but also provides a foundation of pharmabiotics for hyperammonemia as well as various neurological diseases. PMID:29734664

  19. Development of spacecraft toxic gas removal agents

    NASA Technical Reports Server (NTRS)

    Moore, R. S.

    1974-01-01

    The development of agents suitable for removal of CO, NH3, NO2 SO2, and other spacecraft contaminants was approached. An extensive technology review was conducted, yielding a large number of potentially useful materials and/or concepts. Because the two toxic gases of greatest interest, CO and NH3, suggested the use of catalysis principles emphasis was placed on the intestigation of transition metals on various supports. Forty-three materials were prepared or obtained and 25 were tested. Gas chromatographic techniques were used to find seven candidates that effectively managed various combinations of the four toxic gases: none managed all. These candidates included six transition metal-containing preparations and a supported LiOH material. Three commercial charcoals showed some efficiency for the toxic gases and may constitute candidates for enhancement by doping with transition metals.

  20. Effects of chelating agents on the mineral content of root canal dentin.

    PubMed

    Cobankara, Funda Kont; Erdogan, Hilal; Hamurcu, Mehmet

    2011-12-01

    The objective of this in vitro study was to assess the effect of several chelating agents on the mineral content of root dentin. Extracted human mandibular incisor roots were prepared and divided into groups according to the following irrigation protocols: 1) 17% ethylenediaminetetraacetic acid (EDTA); 2) 10% citric acid solution; 3) 18% etidronate; 4) 2.25% peracetic acid; 5) and deionized water (control). Dentin chips were obtained (Gates-Glidden nos. 3, 4, and 5). The levels of different minerals were analyzed with the use of inductively coupled plasma-atomic emission spectrometry (ICP-AES). 1) Peracetic acid significantly decreased P, K, Mg, Na, and S levels compared with the other groups (P < .05). 2) S decreased by different levels in all of the chelating solutions (P < .05), and the greatest decrease was observed in peracetic acid. 3) Ca levels significantly decreased in peracetic acid, citric acid, and EDTA (P < .05). 4) Mn levels significantly decreased in the citric acid and peracetic acid groups (P < .05). 5) Na and Zn levels significantly decreased in the peracetic acid, citric acid, and etidronate groups (P < .05). The chelation agents can create different effects on mineral contents of root dentin, so it is important to know what effects each solution will have on root dentin before their clinical use. In addition, according to the results of this in vitro study, it might be recommended that peracetic acid, in particular, should be used with caution. Copyright © 2011 Mosby, Inc. All rights reserved.

  1. Many-Agent Controlled Teleportation of Multi-qubit Quantum Information via Quantum Entanglement Swapping

    NASA Astrophysics Data System (ADS)

    Zhang, Zhan-Jun; Liu, Yi-Min; Man, Zhong-Xiao

    2005-11-01

    We present a method to teleport multi-qubit quantum information in an easy way from a sender to a receiver via the control of many agents in a network. Only when all the agents collaborate with the quantum information receiver can the unknown states in the sender's qubits be fully reconstructed in the receiver's qubits. In our method, agents's control parameters are obtained via quantum entanglement swapping. As the realization of the many-agent controlled teleportation is concerned, compared to the recent method [C.P. Yang, et al., Phys. Rev. A 70 (2004) 022329], our present method considerably reduces the preparation difficulty of initial states and the identification difficulty of entangled states, moreover, it does not need local Hadamard operations and it is more feasible in technology. The project supported by National Natural Science Foundation of China under Grant No. 10304022

  2. Use of ESI-MS to determine reaction pathway for hydrogen sulphide scavenging with 1,3,5-tri-(2-hydroxyethyl)-hexahydro-s-triazine.

    PubMed

    Madsen, Henrik T; Søgaard, Erik G

    2012-01-01

    To study the reaction between hydrogen sulphide and 1,3,5-tri-(2-hydroxyethyl)-hexahydro-s-triazine, which is an often used hydrogen sulphide scavenger, electro spray ionisation mass spectrometry (ESI-MS) was used. The investigation was carried out in positive mode, and tandem mass spectrometry was used to investigate the nature of unknown peaks in the mass spectra. The reaction was found to proceed as expected from theory with the triazine reacting with hydrogen sulphide to form the corresponding thiadiazine. This species subsequently reacted with a second hydrogen sulphide molecule to form the dithiazine species, hereby confirming previously obtained results and showing the ability of the ESI-MS method for studying the scavenging reaction. The final theoretical product s-trithiane was not detected. Furthermore, fragmentation products of thiadiazine and dithiazine were detected in the solution, and possible pathways and structures were suggested to describe the observed fragments. In these, thiadiazine fragmented to 2-(methylidene amino)-ethanol and 2-(1,3-thiazetidin-3-yl)-ethanol and N-(2-hydroxyethyl)-N-(sulfanylmethyl)-ethaniminium, which underwent a further fragmentation to N-methyl-N-(2-oxoethyl)-methaniminium. Dithiazine fragmented to N-methyl-N-(2-oxoethyl)-methaniminium as well. The by-product from this reaction is methanedithiol, which was not detected due to its low polarity.

  3. Enhanced oxidation stability of quasi core-shell alloyed CdSeS quantum dots prepared through aqueous microwave synthesis technique.

    PubMed

    Zhan, Hong-Ju; Zhou, Pei-Jiang; Ma, Rong; Liu, Xi-Jing; He, Yu-Ning; Zhou, Chuan-Yun

    2014-01-01

    Quasi core shell alloyed CdSeS quantum dots (QDs) have been prepared through a facile aqueous-phase route employing microwave irradiation technique. The optical spectroscopy and structure characterization evidenced the quasi core shell alloyed structures of CdSeS QDs. The X-ray diffraction patterns of the obtained CdSeS QDs displayed peak positions very close to those of bulk cubic CdS crystal structures and the result of X-ray photoelectron spectroscopy data re-confirmed the thick CdS shell on the CdSe core. The TEM images and HRTEM images of the CdSeS QDs ascertained the well-defined spherical particles and a relatively narrow size distribution. On the basis, the stability of the obtained QDs in an oxidative environment was also discussed using etching reaction by H2O2. The experiments result showed the as-prepared QDs present high tolerance towards H2O2, obviously superior to the commonly used CdTe QDs and core-shell CdTe/CdS QDs, which was attributed to the unique quasi core-shell CdSeS crystal structure and the small lattice mismatch between CdSe and CdS semiconductor materials. This assay provided insight to obtain high stable crystal structured semiconductor nanocrystals in the design and synthesis process.

  4. Amino acid–based surfactants: New antimicrobial agents.

    PubMed

    Pinazo, A; Manresa, M A; Marques, A M; Bustelo, M; Espuny, M J; Pérez, L

    2016-02-01

    The rapid increase of drug resistant bacteria makes necessary the development of new antimicrobial agents. Synthetic amino acid-based surfactants constitute a promising alternative to conventional antimicrobial compounds given that they can be prepared from renewable raw materials. In this review, we discuss the structural features that promote antimicrobial activity of amino acid-based surfactants. Monocatenary, dicatenary and gemini surfactants that contain different amino acids on the polar head and show activity against bacteria are revised. The synthesis and basic physico-chemical properties have also been included.

  5. Comparison of Radiation Dose Studies of the 2011 Fukushima Nuclear Accident Prepared by the World Health Organization and the U.S. Department of Defense

    DTIC Science & Technology

    2012-11-01

    R T Comparison of Radiation Dose Studies of the 2011 Fukushima Nuclear Accident Prepared by the World Health Organization and the U.S. Department...AND SUBTITLE Comparison of Radiation Dose Studies of the 2011 Fukushima Nuclear Accident Prepared by the World Health Organization and the U.S...in Japan on March 11, 2011 led to releases of radioactive materials from the Tokyo Electric Power Company’s Fukushima Daiichi Nuclear Power Station

  6. Preparation and gas sensing properties of novel CdS-supramolecular organogel hybrid films

    NASA Astrophysics Data System (ADS)

    Xia, Huiyun; Peng, Junxia; Liu, Kaiqiang; Li, Chen; Fang, Yu

    2008-05-01

    A novel CdS-supramolecular organogel hybrid film with unusual morphology has been fabricated by exposing a supramolecular organogel film containing Cd(Ac)2 in an H2S atmosphere at room temperature. The organogel film was prepared by spin-coating a LMOG (low-molecular weight organic gelator) gel of dmethyl sulfoxide onto a glass plate substrate. XRD, SEM, EDS, TG-DTA, UV-vis, PL (photoluminescence) spectroscopy and PL lifetime measurements were employed to characterize the film. It was shown that the organogel film had functioned as a template to control the morphology of the final hybrid film. The quantities and sizes of the CdS particles embedded in the organogel films can be easily altered by varying the initial concentration of Cd(Ac)2. Importantly, the PL of the hybrid film is sensitive to the presence of some volatile organic monoamines and diamines. The selectivity and reversibility of the sensing process were investigated.

  7. Preparation, in vitro release, and pharmacokinetics in rabbits of lyophilized injection of sorafenib solid lipid nanoparticles

    PubMed Central

    Zhang, Hong; Zhang, Fu-Ming; Yan, Shi-Jun

    2012-01-01

    Sorafenib solid lipid nanoparticles (S-SLN) were prepared by emulsion evaporation–solidification at low temperature. Morphology was examined by transmission electron microscope. Particle size and zeta potential were determined by laser granularity equipment. Encapsulation efficiency (EE) was detected by Sephadex gel chromatography and high-performance liquid chromatography (HPLC). The in vitro release profile of S-SLN was studied with dialysis technology. The lyophilized injection of S-SLN was prepared by freeze drying and analyzed by differential scanning calorimetry. The plasma concentration of sorafenib in blood was determined by HPLC. The solid lipid nanoparticles assumed a spherical shape with an even distribution of diameter and particle size 108.23 ± 7.01 nm (n = 3). The polydispersity index, zeta potential, and EE were determined to be 0.25 ± 0.02, −16.37 ± 0.65 mV, and 93.49% ± 1.87%, respectively (n = 3). The in vitro release accorded with the Weibull distribution model. An equal volume of 15% (w/v) mannitol performed better as the protective agent for a lyophilized injection of S-SLN with a new material phase formation. The pharmacokinetic processes of sorafenib solution and lyophilized injection of S-SLN in vivo were in accordance with the two-compartment and one-compartment models, respectively. S-SLN nanoparticles are thus considered a promising drug-delivery system. PMID:22787390

  8. Enhanced control of end-group composition in poly(3-hexylthiophene)s prepared by GRIM

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kochemba, William Michael; Kilbey, II, S Michael; Pickel, Deanna L

    The ability to prepare well-defined semiconducting polymers is essential for understanding the link between structure and function in organic photovoltaic devices. A general method for enhanced control of the degree of functionality of end-functionalized poly(3-hexylthiophene)s (P3HT) prepared by Grignard Metathesis (GRIM) polymerization has been developed. In the absence of additives, the degree of functionality of end-functional P3HTs prepared by quenching of the GRIM polymerization with a Grignard reagent is dependent on the Grignard reagent utilized. In this study, additives such as styrene and 1-pentene are shown to alter the end-group composition of tolyl-functionalized P3HTs as determined by MALDI-TOF MS. Inmore » particular, when quenching the GRIM polymerization with tolylmagnesium bromide a modest decrease in the difunctional product is observed, and the yield of the monofunctional product increases significantly. Temperature and lithium chloride (LiCl) addition also play impactful roles. Monofunctional P3HT is found to be the major product (65%) when the functionalization is done in the presence of LiCl and styrene at 0oC, whereas in the absence of additives the monofunctional product is present at only 20%.« less

  9. A facile and green preparation of reduced graphene oxide using Eucalyptus leaf extract

    NASA Astrophysics Data System (ADS)

    Li, Chengyang; Zhuang, Zechao; Jin, Xiaoying; Chen, Zuliang

    2017-11-01

    In this paper, a green and facile synthesis of reduced graphene oxide (GO) by Eucalyptus leaf extract (EL-RGO) was investigated, which was characterized with ultraviolet-visible spectroscopy (UV), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and Thermal gravimetric analysis (TG). Eucalyptus leaf extract also play both reducing and capping stabilizing agents prepared EL-RGO as shown a good stability and electrochemical properties. This approach could provide an alternative method to prepare EL-RGO in large-scale production. Moreover, the good electrochemical property and biocompatibility can be used in various applications. In addition, the merit of this study is that both the oxidized products and the reducing agents are environmental friendly by green reduction.

  10. Nanoparticle-Based Electrochemical Immunosensor for the Detection of Phosphorylated Acetylcholinesterase: An Exposure Biomarker of Organophosphate Pesticides and Nerve AgentsOrganophosphate Pesticides and Nerve Agents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Guodong; Wang, Jun; Barry, Richard C.

    A nanoparticle-based electrochemical immunosensor has been developed for the detection of phosphorylated acetylcholinesterase (AChE) adducts, which is a potential exposure biomarker for organophosphate pesticides (OP) and chemical warfare nerve agent exposures. Zirconia nanoparticles (ZrO2 NPs) were used as selective sorbents to capture the phosphorylated AChE adduct, and quantum dots (ZnS@CdS, QDs) were used as tags to label monoclonal anti-AChE antibody to track the immunorecognition events. The sandwich-like immunoreactions were performed among the ZrO2 NPs, which were pre-coated on a screen printed electrode (SPE) by electrodeposition, phosphorylated AChE and QD-anti-AChE. The captured QD tags were determined on the SPE by electrochemicalmore » stripping analysis of its metallic component (cadmium) after an acid-dissolution step. Paraoxon was used as a model OP insecticide to prepare the phosphorylated AChE adduct to demonstrate the proof of principle for this sensor technology. The paraoxon-AChE adduct was characterized by Fourier Transform Infrared Spectrum, and the binding affinity of anti-AChE to the paraoxon-AChE was validated with an enzyme-linked immunosorbent assay. The parameters (e.g., amount of ZrO2 NP, QD-anti-AChE concentration,) that govern the electrochemical response of immunosensors were optimized. The voltammetric response of the immunosensor is highly linear over the range of 10 pM to 4 nM paraoxon-AChE, and the limit of detection is estimated to be 8 pM. This new nanoparticle-based electrochemical immunosensor thus provides a sensitive and quantitative tool for biomonitoring exposure to OP pesticides and nerve agents.« less

  11. A novel gallium bisaminothiolate complex as a myocardial perfusion imaging agent

    PubMed Central

    Plössl, Karl; Chandra, Rajesh; Qu, Wenchao; Lieberman, Brian P.; Kung, Mei-Ping; Zhou, Rong; Huang, Bin; Kung, Hank F.

    2010-01-01

    The development of new myocardial perfusion imaging agents for positron emission tomography (PET) may improve the resolution and quantitation of changes in regional myocardial perfusion measurement. It is known that a 68Ge/68Ga generator can provide a convenient source of PET tracers because of the long physical half-life of 68Ge (271 days). A new ligand, 7,8-dithia-16,24-diaza-trispiro[5.2.5.2.5.3] pentacosa-15,24-diene, which consists of a N2S2-chelating core incorporated into three cyclohexyl rings, was prepared. To test feasibility and potential utility, the N2S2 ligand was successfully labeled and tested with 67Ga (half-life=3.26 day; γ=93.3, 184.6 and 300.2 keV), which showed >92% radiochemical purity. The corresponding “cold” Ga complex was synthesized, and its structure containing a pyramidal N2S2 chloride core was elucidated with X-ray crystallography. In vivo biodistribution of this novel 67Ga complex, evaluated in normal rats, exhibited excellent heart uptake and retention, with 2.1% and 0.9% initial dose/organ at 2 and 60 min, respectively, after an intravenous injection. Autoradiography was performed in normal rats and in rats that had the left anterior descending coronary artery permanently ligated surgically. Autoradiography showed an even uptake of activity in the normal heart, and there was a distinctively lower uptake in the damaged side of the surgically modified heart. In conclusion, the new N2S2 ligand was readily prepared and labeled with radioactive 67Ga. Biodistribution in rats revealed high initial heart uptake and relatively high retention reflecting regional myocardial perfusion. PMID:18158947

  12. Effect of sulfur source on photocatalytic degradation performance of CdS/MoS2 prepared with one-step hydrothermal synthesis.

    PubMed

    Wang, Yanfeng; Chen, Wei; Chen, Xiao; Feng, Huajun; Shen, Dongsheng; Huang, Bin; Jia, Yufeng; Zhou, Yuyang; Liang, Yuxiang

    2018-03-01

    CdS/MoS 2 , an extremely efficient photocatalyst, has been extensively used in hydrogen photoproduction and pollutant degradation. CdS/MoS 2 can be synthesized by a facile one-step hydrothermal process. However, the effect of the sulfur source on the synthesis of CdS/MoS 2 via one-step hydrothermal methods has seldom been investigated. We report herein a series of one-step hydrothermal preparations of CdS/MoS 2 using three different sulfur sources: thioacetamide, l-cysteine, and thiourea. The results revealed that the sulfur source strongly affected the crystallization, morphology, elemental composition and ultraviolet (UV)-visible-light-absorption ability of the CdS/MoS 2 . Among the investigated sulfur sources, thioacetamide provided the highest visible-light absorption ability for CdS/MoS 2 , with the smallest average particle size and largest surface area, resulting in the highest efficiency in Methylene Blue (MB) degradation. The photocatalytic activity of CdS/MoS 2 synthesized from the three sulfur sources can be arranged in the following order: thioacetamide>l-cysteine>thiourea. The reaction rate constants (k) for thioacetamide, l-cysteine, and thiourea were estimated to be 0.0197, 0.0140, and 0.0084min -1 , respectively. However, thioacetamide may be limited in practical application in terms of its price and toxicity, while l-cysteine is relatively economical, less toxic and exhibited good photocatalytic degradation performance toward MB. Copyright © 2017. Published by Elsevier B.V.

  13. Transcrystalline interphases in natural fiber-PP composites: effect of coupling agent

    Treesearch

    A.R. Sanadi; D.F. Caulfield

    2000-01-01

    The interest in lignocellulosic fiber composites has been growing in recent years because of their high specific properties. In this work, a new technique was used to prepare specimen to observe the transcrystalline zones in kenaf fiber-polypropylene composites. A maleated polypropylene (MAPP) coupling agent was used to improve the stress-transfer efficiency in the...

  14. Chelating agents.

    PubMed

    Bergan, T; Klaveness, J; Aasen, A J

    2001-01-01

    The antibacterial activity of metal ions, metal chelates, and molecules with chelating ability for polyvalent cations have been evaluated. The chelator N, N'-ethylenebis[2-(2-hydroxyphenyl)-glycine] (EHPG) exerted moderate-to-good activity against isolates of pathogenic bacteria and fungi. Other chelating agents such as ethylenediamine-tetraacetic acid (EDTA) and diethylene-triamine-pentaacetic acid (DTPA) revealed weak-to-moderate activity. Metal chelation of ligands reduced the activity of EDTA and DTPA. Copyright 2001 S. Karger AG, Basel

  15. Assessment of water-soluble thiourea-formaldehyde (WTF) resin for stabilization/solidification (S/S) of heavy metal contaminated soils.

    PubMed

    Liu, She-Jiang; Jiang, Jia-Yu; Wang, Shen; Guo, Yu-Peng; Ding, Hui

    2018-03-15

    Stabilization/Solidification (S/S) can be regarded as necessary for remediation of heavy metal contaminated soil. There is, however, solid agent is not very convenient to use. Water-soluble thiourea-formaldehyde (WTF) is a novel chelating agent, which has more practical applications. The process of WTF resin for S/S process of heavy metal contaminated soils was studied. Laboratory-prepared slurries, made of field soils spiked with Cd 2+ and Cr 6+ were treated with WTF resin. The toxicity characteristic leaching procedure (TCLP) showed that with 2 wt% WTF, in the neutral condition of soil after treatment for 7 d, the leaching concentrations of Cd 2+ and Cr 6+ in contaminated soil were decreased by 80.3% and 92.6% respectively. Moreover, Tessier sequence extraction procedure showed WTF resin reduced the leaching concentration by transforming heavy metal from exchange form to organic form. The structure of WTF is obtained according to elemental analysis result and reaction mechanism. Through analysis of the infrared spectrogram of WTF and WTF heavy mental chelating precipitation, WTF can form stable chelate with heavy mental through coordination. The significant groups are hydroxyl, nitrogen and sulphur function groups in WTF mainly. Toxicology test revealed that the WTF resin is nontoxic to microorganism in the soils. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Endogenous Price Bubbles in a Multi-Agent System of the Housing Market

    PubMed Central

    2015-01-01

    Economic history shows a large number of boom-bust cycles, with the U.S. real estate market as one of the latest examples. Classical economic models have not been able to provide a full explanation for this type of market dynamics. Therefore, we analyze home prices in the U.S. using an alternative approach, a multi-agent complex system. Instead of the classical assumptions of agent rationality and market efficiency, agents in the model are heterogeneous, adaptive, and boundedly rational. We estimate the multi-agent system with historical house prices for the U.S. market. The model fits the data well and a deterministic version of the model can endogenously produce boom-and-bust cycles on the basis of the estimated coefficients. This implies that trading between agents themselves can create major price swings in absence of fundamental news. PMID:26107740

  17. Preparation of tyrosinase inhibitors and antibrowning agents using green technology.

    PubMed

    Dong, Xue; Zhang, Yinan; He, Jia-Liang; Zhang, Shuang; Zeng, Mao-Mao; Chen, Jie; Zheng, Zong-Ping

    2016-04-15

    Chalcones and their derivatives have attracted great interests in recent years for their comprehensive biological activities. In this study, 2,4,2',4'-tetrahydroxychalcone and its two derivatives, 1,3,5-tris-(2,4-dihydroxy-phenyl)pentane-1,5-dione (new compound) and 7,2',4'-trihydroxyflavanone, were synthesized through one-pot green procedure catalyzed by boric acid in polyethylene glycol 400. Their structures were identified by ESI-MS and NMR spectral. Tyrosinase inhibitory activity and antibrowning test results showed that compounds 1-3 exhibited strong tyrosinase inhibitory activities and significant antibrowning effects on the fresh-cut lotus root slices at room temperature in 48 h. Among them, 0.01% 1,3,5-tris-(2,4-dihydroxy-phenyl)pentane-1,5-dione combined with 0.5% VC showed the best antibrowning ability. In brief, this study offers a protocol for one-pot green synthesis of high efficiency tyrosinase inhibitors which may be suitable as antibrowning agents for fresh-cut vegetables. More important, this study developed a new type of 1,5-dione derivative which may serve as new lead structures for novel tyrosinase inhibitors discovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Adaptivity in Agent-Based Routing for Data Networks

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Kirshner, Sergey; Merz, Chris J.; Turner, Kagan

    2000-01-01

    Adaptivity, both of the individual agents and of the interaction structure among the agents, seems indispensable for scaling up multi-agent systems (MAS s) in noisy environments. One important consideration in designing adaptive agents is choosing their action spaces to be as amenable as possible to machine learning techniques, especially to reinforcement learning (RL) techniques. One important way to have the interaction structure connecting agents itself be adaptive is to have the intentions and/or actions of the agents be in the input spaces of the other agents, much as in Stackelberg games. We consider both kinds of adaptivity in the design of a MAS to control network packet routing. We demonstrate on the OPNET event-driven network simulator the perhaps surprising fact that simply changing the action space of the agents to be better suited to RL can result in very large improvements in their potential performance: at their best settings, our learning-amenable router agents achieve throughputs up to three and one half times better than that of the standard Bellman-Ford routing algorithm, even when the Bellman-Ford protocol traffic is maintained. We then demonstrate that much of that potential improvement can be realized by having the agents learn their settings when the agent interaction structure is itself adaptive.

  19. One-step synthesis of water-dispersible ultra-small Fe3O4 nanoparticles as contrast agents for T1 and T2 magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Wang, Guannan; Zhang, Xuanjun; Skallberg, Andreas; Liu, Yaxu; Hu, Zhangjun; Mei, Xifan; Uvdal, Kajsa

    2014-02-01

    Uniform, highly water-dispersible and ultra-small Fe3O4 nanoparticles were synthesized via a modified one-step coprecipitation approach. The prepared Fe3O4 nanoparticles not only show good magnetic properties, long-term stability in a biological environment, but also exhibit good biocompatibility in cell viability and hemolysis assay. Due to the ultra-small sized and highly water-dispersibility, they exhibit excellent relaxivity properties, the 1.7 nm sized Fe3O4 nanoparticles reveal a low r2/r1 ratio of 2.03 (r1 = 8.20 mM-1 s-1, r2 = 16.67 mM-1 s-1) and the 2.2 nm sized Fe3O4 nanoparticles also appear to have a low r2/r1 ratio of 4.65 (r1 = 6.15 mM-1 s-1, r2 = 28.62 mM-1 s-1). This demonstrates that the proposed ultra-small Fe3O4 nanoparticles have great potential as a new type of T1 magnetic resonance imaging contrast agents. Especially, the 2.2 nm sized Fe3O4 nanoparticles, have a competitive r1 value and r2 value compared to commercial contrasting agents such as Gd-DTPA (r1 = 4.8 mM-1 s -1), and SHU-555C (r2 = 69 mM-1 s-1). In vitro and in vivo imaging experiments, show that the 2.2 nm sized Fe3O4 nanoparticles exhibit great contrast enhancement, long-term circulation, and low toxicity, which enable these ultra-small sized Fe3O4 nanoparticles to be promising as T1 and T2 dual contrast agents in clinical settings.Uniform, highly water-dispersible and ultra-small Fe3O4 nanoparticles were synthesized via a modified one-step coprecipitation approach. The prepared Fe3O4 nanoparticles not only show good magnetic properties, long-term stability in a biological environment, but also exhibit good biocompatibility in cell viability and hemolysis assay. Due to the ultra-small sized and highly water-dispersibility, they exhibit excellent relaxivity properties, the 1.7 nm sized Fe3O4 nanoparticles reveal a low r2/r1 ratio of 2.03 (r1 = 8.20 mM-1 s-1, r2 = 16.67 mM-1 s-1) and the 2.2 nm sized Fe3O4 nanoparticles also appear to have a low r2/r1 ratio of 4.65 (r1 = 6.15 mM-1 s

  20. Alkylating agent (MNU)-induced mutation in space environment

    NASA Astrophysics Data System (ADS)

    Ohnishi, T.; Takahashi, A.; Ohnishi, K.; Takahashi, S.; Masukawa, M.; Sekikawa, K.; Amano, T.; Nakano, T.; Nagaoka, S.

    2001-01-01

    In recent years, some contradictory data about the effects of microgravity on radiation-induced biological responses in space experiments have been reported. We prepared a damaged template DNA produced with an alkylating agent (N-methyl-N-nitroso urea; MNU) to measure incorrect base-incorporation during DNA replication in microgravity. We examined whether mutation frequency is affected by microgravity during DNA replication for a DNA template damaged by an alkylating agent. Using an in vitro enzymatic reaction system, DNA synthesis by Taq polymerase or polymerase III was done during a US space shuttle mission (Discovery, STS-91). After the flight, DNA replication and mutation frequencies were measured. We found that there was almost no effect of microgravity on DNA replication and mutation frequency. It is suggested that microgravity might not affect at the stage of substrate incorporation in induced-mutation frequency.

  1. Fabrication of solar cells based on Cu2ZnSnS4 prepared from Cu2SnS3 synthesized using a novel chemical procedure

    NASA Astrophysics Data System (ADS)

    Correa, John M.; Becerra, Raúl A.; Ramírez, Asdrubal A.; Gordillo, Gerardo

    2016-11-01

    Solar cells based on kesterite-type Cu2ZnSnS4 (CZTS) thin films were fabricated using a chemical route to prepare the CZTS films, consisting in sequential deposition of Cu2SnS3 (CTS) and ZnS thin films followed by annealing at 550 °C in nitrogen atmosphere. The CTS compound was prepared in a one-step process using a novel chemical procedure consisting of simultaneous precipitation of Cu2S and SnS2 performed by diffusion membranes assisted CBD (chemical bath deposition) technique. Diffusion membranes were used to optimize the kinetic growth through a moderate control of release of metal ions into the work solution. As the conditions for the formation in one step of the Cu2SnS3 compound have not yet been reported in literature, special emphasis was put on finding the parameters that allow growing the Cu2SnS3 thin films by simultaneous precipitation of Cu2S and SnS2. For that, we propose a methodology that includes numerical solution of the equilibrium equations that were established through a study of the chemical equilibrium of the system SnCl2, Na3C6H5O7·2H2O, CuCl2 and Na2S2O3·5H2O. The formation of thin films of CTS and CZTS free of secondary phases grown with a stoichiometry close to that corresponding to the Cu2SnS3 and Cu2ZnSnS4 phases, was verified through measurements of X-ray diffraction (XRD) and Raman spectroscopy. Solar cell with an efficiency of 4.2%, short circuit current of 16.2 mA/cm2 and open-circuit voltage of 0.49 V was obtained.

  2. Microstructure control of SOFC cathode material: The role of dispersing agent

    NASA Astrophysics Data System (ADS)

    Ismail, Ismariza; Jani, Abdul Mutalib Md; Osman, Nafisah

    2017-09-01

    In the present works, La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode powders were synthesized by a sol-gel method with the aid of ethylene glycol which served as the dispersing agent. The phase formation and morphology of the powders were examined by X-Ray diffractometer (XRD) and field emission scanning electron microscopy (FESEM), respectively. The electrochemical properties of the synthesized cathode were obtained using an electrochemical impedance spectroscopy (EIS). The characteristic peaks for LSCF phase appears in the X-ray diffractogram after calcined at 500 °C and complete formation of LSCF single phase was attained at 700 °C. FESEM micrographs showed the presence of spherical particles of the powders with approximate particle size between 10 to 60 nm along with agglomerate morphologies. Well dispersed particles and fewer aggregates were observed for samples prepared with addition of ethylene glycol as the synthesizing aid. The surface area obtained for powder sample prepared with the aid of dispersing agent is 12.0 m2g-1. The EIS measurement results depicts a lower area specific resistance (ASR) obtained for sample prepared with addition of the ethylene glycol as compared to the pristine sample. The present results encourage the optimization of the cathode particle design in order to further improve the cathode performance.

  3. Biocompatible, Biodegradable, and Enzymatic-Cleavable MRI Contrast Agents for Early Detection of Bone Metastatic Breast Cancer

    DTIC Science & Technology

    2012-04-01

    detection of bone metastasis from breast cancer. The proposed imaging agent is consist of bone targeting moiety of Asp8 and MRI imaging moiety of DOTA ...peptide onto DOTA followed by Gd complexation was performed to achieve the proposed imaging agent. Non-targeting and CTSK-insensitive controls were...synthesis (SPPS) strategy, and purified by preparative HPLC. The chemical structures of peptides were shown below. Peptides reacted with DOTA -NHS

  4. Hybrid evolutionary computing model for mobile agents of wireless Internet multimedia

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    2001-03-01

    The ecosystem is used as an evolutionary paradigm of natural laws for the distributed information retrieval via mobile agents to allow the computational load to be added to server nodes of wireless networks, while reducing the traffic on communication links. Based on the Food Web model, a set of computational rules of natural balance form the outer stage to control the evolution of mobile agents providing multimedia services with a wireless Internet protocol WIP. The evolutionary model shows how mobile agents should behave with the WIP, in particular, how mobile agents can cooperate, compete and learn from each other, based on an underlying competition for radio network resources to establish the wireless connections to support the quality of service QoS of user requests. Mobile agents are also allowed to clone themselves, propagate and communicate with other agents. A two-layer model is proposed for agent evolution: the outer layer is based on the law of natural balancing, the inner layer is based on a discrete version of a Kohonen self-organizing feature map SOFM to distribute network resources to meet QoS requirements. The former is embedded in the higher OSI layers of the WIP, while the latter is used in the resource management procedures of Layer 2 and 3 of the protocol. Algorithms for the distributed computation of mobile agent evolutionary behavior are developed by adding a learning state to the agent evolution state diagram. When an agent is in an indeterminate state, it can communicate to other agents. Computing models can be replicated from other agents. Then the agents transitions to the mutating state to wait for a new information-retrieval goal. When a wireless terminal or station lacks a network resource, an agent in the suspending state can change its policy to submit to the environment before it transitions to the searching state. The agents learn the facts of agent state information entered into an external database. In the cloning process, two

  5. Preparation high photocatalytic activity of CdS/halloysite nanotubes (HNTs) nanocomposites with hydrothermal method

    NASA Astrophysics Data System (ADS)

    Xing, Weinan; Ni, Liang; Huo, Pengwei; Lu, Ziyang; Liu, Xinlin; Luo, Yingying; Yan, Yongsheng

    2012-10-01

    A novel nanocatalyst CdS/halloysite nanotubes (HNTs) was synthesized by hydrothermal method with direct growth of CdS nanoparticles on the surface of HNTs. The as-prepared photocatalysts had been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), UV-vis diffuse reflectance spectra (UV-vis DRS), Fourier transform infrared (FT-IR) and the thermo gravimetric analysis (TGA). The photocatalytic activity of the sample was evaluated by the degradation of tetracycline (TC) under visible light irradiation. Benefit from the excellent properties of CdS and HNTs, the photocatalyst exhibited good photocatalytic activity and stability. In order to find out the optimum synthesis condition to obtain the best photocatalytic activity, a series of experiments were performed with different CdS loading capacity, different sources of sulfide and different hydrothermal temperatures, etc. The best photodegradation rate could reach 93% in 60 min under visible light irradiation. Therefore, the combination of CdS nanoparticles with HNTs endowed this material with a potential use in environmental treatments in industries.

  6. Properties of novel bone hemostat prepared using sugar-modified hydroxyapatite, phosphoryl oligosaccharides of calcium and thermoplastic resin

    NASA Astrophysics Data System (ADS)

    Mimira, Tokio; Umeda, Tomohiro; Musha, Yoshiro; Itatani, Kiyoshi

    2013-12-01

    A novel hemostatic agent was prepared using phosphoryl oligosaccharides of calcium (POs-Ca), hydroxyapatite (Ca10(PO4)6(OH)2; HAp) obtained by the hydrolysis of POs-Ca or sugar-containing HAp (s-HAp; 60.3 mass% calcium-deficient HAp and 39.5 mass% organic materials, Ca/P ratio = 1.56) and thermoplastic resin (the mixture of random copolymer of ethylene oxide/propylene oxide (EPO) and polyethylene oxide (EO); EPO : EO : water = 25 : 15 : 60 (mass ratio); 25EPO-15EO). The gel formed by mixing 25EPO-15EO with water (25EPO-15EO/water mass ratio: 0.20) was flash frozen at -80°C, freeze-dried at -50°C for 15 h and then ground using mixer. The consistency conditions of hemostats mixed with POs-Ca or s-HAp were optimized for the practical uses. The mean stanching times of hemostats were: s-HAp/25EPO-15EO (8.2 h; s-HAp/25EPO-15EO = 0.20) > 25EPO-15EO (5.3 h) > POs-Ca/25EPO-15EO (4.7 h; POs-Ca/25EPO-15EO = 0.20). The gentamicin, a typical antibiotic agent, loaded s-HAp/25EPO-15EO composite hemostat showed the steady state releasing in phosphate buffered saline till 10 h immersion at 37.0°C.

  7. Characterization of chemical agent transport in paints.

    PubMed

    Willis, Matthew P; Gordon, Wesley; Lalain, Teri; Mantooth, Brent

    2013-09-15

    A combination of vacuum-based vapor emission measurements with a mass transport model was employed to determine the interaction of chemical warfare agents with various materials, including transport parameters of agents in paints. Accurate determination of mass transport parameters enables the simulation of the chemical agent distribution in a material for decontaminant performance modeling. The evaluation was performed with the chemical warfare agents bis(2-chloroethyl) sulfide (distilled mustard, known as the chemical warfare blister agent HD) and O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX), an organophosphate nerve agent, deposited on to two different types of polyurethane paint coatings. The results demonstrated alignment between the experimentally measured vapor emission flux and the predicted vapor flux. Mass transport modeling demonstrated rapid transport of VX into the coatings; VX penetrated through the aliphatic polyurethane-based coating (100 μm) within approximately 107 min. By comparison, while HD was more soluble in the coatings, the penetration depth in the coatings was approximately 2× lower than VX. Applications of mass transport parameters include the ability to predict agent uptake, and subsequent long-term vapor emission or contact transfer where the agent could present exposure risks. Additionally, these parameters and model enable the ability to perform decontamination modeling to predict how decontaminants remove agent from these materials. Published by Elsevier B.V.

  8. Effect of complexing agents on the electrochemical performance of LiFePO4/C prepared by sol-gel method

    PubMed Central

    2012-01-01

    LiFePO4/C is synthesized via sol-gel method using Fe3+ as iron sources and different complexing agents, followed by sintering at high temperature for crystallization. The amount of carbon in these composites is less than 6.8 wt.%, and the X-ray diffraction experiment confirms that all samples are pure single phase indexed with the orthorhombic Pnma space group. The particle size of the LiFePO4/C synthesized by acetic acid as a complexing agent is very fine with a size of 200 nm. The electrochemical performance of this material, including reversible capacity, cycle number, and charge-discharge characteristics, is better than those of LiFePO4/C synthesized by other complexing agents. The cell of this sample can deliver a discharge capacity of 161.1 mAh g-1 at the first cycle. After 30 cycles, the capacity decreases to 157.5 mAh g-1, and the capacity fading rate is 2.2%. The mechanism is studied to explain the effect of a complexing agent on the synthesis of LiFePO4/C by sol-gel method. The results show that the complexing agent with a low stability constant may be proper for the synthetic process of LiFePO4/C via sol-gel method. PMID:22221711

  9. Effect of complexing agents on the electrochemical performance of LiFePO4/C prepared by sol-gel method

    NASA Astrophysics Data System (ADS)

    Yang, Rong; Kang, Erwei; Jiang, Bailing; Ahn, Jou-Hyeon

    2012-01-01

    LiFePO4/C is synthesized via sol-gel method using Fe3+ as iron sources and different complexing agents, followed by sintering at high temperature for crystallization. The amount of carbon in these composites is less than 6.8 wt.%, and the X-ray diffraction experiment confirms that all samples are pure single phase indexed with the orthorhombic Pnma space group. The particle size of the LiFePO4/C synthesized by acetic acid as a complexing agent is very fine with a size of 200 nm. The electrochemical performance of this material, including reversible capacity, cycle number, and charge-discharge characteristics, is better than those of LiFePO4/C synthesized by other complexing agents. The cell of this sample can deliver a discharge capacity of 161.1 mAh g-1 at the first cycle. After 30 cycles, the capacity decreases to 157.5 mAh g-1, and the capacity fading rate is 2.2%. The mechanism is studied to explain the effect of a complexing agent on the synthesis of LiFePO4/C by sol-gel method. The results show that the complexing agent with a low stability constant may be proper for the synthetic process of LiFePO4/C via sol-gel method.

  10. Preparation and evaluation of effect on Escherichia coli and Staphylococcus aureus of radiolabeled ampicillin-loaded graphene oxide nanoflakes.

    PubMed

    Yurt, Fatma; Ersöz, Onur Alp; Harputlu, Ersan; Ocakoglu, Kasim

    2018-06-01

    Ampicillin is a one of effective antibiotics against Gram-positive and Gram-negative bacteria. This study aimed to label ampicillin-loaded graphene oxide nanoflake (AMP-GO) with 99m Tc and evaluate of its in vitro binding to Staphylococcus aureus and Escherichia coli. Firstly, ampicillin was loaded into graphene oxide nanoflake prepared. AMP-GO was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) techniques, and the amount of loaded ampicillin onto GO was determined by UV-Vis absorption spectroscopy. AMP and AMP-GO were labeled with 99m Tc using stannous chloride reducing agent. Labeling efficiency of 99m Tc-AMP-GO was found to be 97.66 ± 2.06%. 99m Tc-AMP-GO has higher binding efficiencies to both S. aureus and E. coli than 99m Tc-AMP. 99m Tc-AMP-GO could be promising candidate as agent infection nuclear imaging. Furthermore, in vivo studies of 99m Tc-AMP-GO with infected rats are planned to be performed. © 2018 John Wiley & Sons A/S.

  11. Polymeric contrast agents for medical imaging.

    PubMed

    Torchilin, V P

    2000-09-01

    Synthetic polymers and co-polymers are described, to be used as carriers of reporter groups for gamma-, magnetic resonance (MR), and computed tomography (CT) imaging. Those compounds include polychelating and amphiphilic polymers and serve as key components of various contrast agents. Single terminus-activated polychelating polymers were synthesized using poly-L-lysine (PLL) as a main chain and chelating moieties (such as diethylene triamine pentaacetic acid or DTPA) as side groups. These polymers were used for the modification of diagnostic monoclonal antibodies to increase their load with reporter metal atoms. As a result, better images within shorter time intervals were obtained in animal experiments. The application of liposomes and micelles as carriers for diagnostic imaging agents in experimental and clinical medicine is considered. The load of liposomes and micelles with contrast agents for gamma- and MR imaging (MRI) was sharply increased by using polychelating polymers additionally modified on one end with a hydrophobic phospholipid residue to give amphiphilic polymers. Such polymers easily incorporate the liposome membrane or micelle core and provide better loading of liposomes and micelles with reporter metals and, consequently, better and faster imaging of various physiological compartments, such as lymphatic and vascular systems. A block-copolymer of methoxy-poly(ethylene glycol) (MPEG) and iodine-substituted PLL was synthesized to prepare long-circulating contrast agent for CT imaging of the blood pool. In the aqueous solution, this copolymer forms stable and heavily loaded with iodine (up to 30% of iodine by weight) micelles. These micelle were successfully used for CT visualization of the vascular network in experimental animals. General trends in developing contrast polymers are discussed.

  12. Synergistic thermoradiotherapy based on PEGylated Cu3BiS3 ternary semiconductor nanorods with strong absorption in the second near-infrared window.

    PubMed

    Li, Ang; Li, Xiang; Yu, Xujiang; Li, Wei; Zhao, Ruyi; An, Xiao; Cui, Daxiang; Chen, Xiaoyuan; Li, Wanwan

    2017-01-01

    In this work, we report a successful synthesis of copper bismuth sulfide nanorods (NRs) with broad and strong photoabsorption ranging from ultraviolet (UV) to near-infrared (NIR) wavelengths, which can be used as a 1064 nm-laser-driven photothermal agent with the photothermal conversion efficiency of 40.7%, noticeably higher than most of the reported PTT agents working in NIR-II window. The as-prepared PEGylated Cu 3 BiS 3 NRs were used as photoacoustic imaging (PAI) and CT imaging agents due to their strong NIR absorption and large X-ray attenuation coefficient of bismuth. We are the first to demonstrate that a small quantity of PEGylated Cu 3 BiS 3 NRs in tumors can concentrate radiation energy and trigger mild PTT under NIR-II irradiation and thus, these particles could be used as a novel, synergistic thermoradiotheraputic agent that enhances the efficacy of radiotherapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Preparation of Chitin Nanofibers-Gold Metallic Nanocomposite by Phase Transfer Method

    NASA Astrophysics Data System (ADS)

    Shervani, Zameer; Taisuke, Yukawa; Ifuku, Shinsuke; Saimoto, Hiroyuki; Morimoto, Minoru

    2012-10-01

    Chitin nanofibers (CNFs)-Au(0) nanoparticles (Au NPs) blends in dispersion, flakes and thin film or sheet forms were first prepared by mixing pre-organized Au NPs prepared in triblock copolymer with diluted CNFs suspension. Water soluble polymer triblock copolymer poly (methyl vinyl ether, PMVE) in the amount 0.6 wt.% was used to prepare NPs and 0.12 wt.% net chitin content was used as CNFs suspension to prepare the blended composite. Au NPs of size 4.4 nm (σ = 1.2) were obtained when Au salt (HAuCl4ṡ3H2O (hydrogen tetrachloroaurate (III) trihydrate) was reduced by 5 equivalents of NaBH4. PMVE polymer acted as a stabilizing or capping agent for pre-organized NPs. Completion of reaction was fast, all salt reduced to metallic form in just 15 min after the addition of NaBH4. CNFs (1 wt.% chitin) which was used to prepare CNFs-Au NPs blend composite were prepared from crab shell in never dried acidic condition by established combination of chemical and mechanical processes that gave 25-40 nm width and high aspect ratio CNFs. When polymer capped Au NPs mixed with CNF suspension, all Au NPs and 56% polymer were mass transferred from water phase to entangle with more polar moieties of CNFs-water suspension as no trace of Au NPs were noticed in water-polymer mother liquor after blending with CNFs suspension. Particles size of CNFs-Au NPs composite was measured by employing TEM, SAXS and SEM techniques. CNFs-Au NPs composite were characterized in solution and compressed dried sheet form by recording digital images, UV-vis and XRD spectroscopies. CNFs-Au NPs suspension had antibacterial activity against gram positive bacteria S. aureus.

  14. SU-E-I-84: MRI Relaxation Properties of a Pre-Clinical Hypoxia-Sensitive MRI Contrast Agent

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yee, S; Wilson, G; Chavez, F

    2014-06-01

    Purpose: A possible hypoxia-sensitive MRI agent, hexamethyldisiloxane (HMDSO), has been tried to image oxygen level in proton-based MRI (Kodibagkar et al, NMR Biomed, 2008). The induced changes of T1 (or R1) value by the HMDSO as the oxygenation level changes are the principle that the hypoxia agent is based on: the R1 increases as the oxygen level increases. However, as reported previously, the range of R1 values (0.1–0.3 s-1, corresponding to 3–10 s of T1) is not in the range where a regular MRI technique can easily detect the change. In order for this agent to be widely applied inmore » an MRI environment, more relaxation properties of this agent, including T1 in the rotating frame (T1rho) and T2, need to be explored. Here, the relaxation properties of this agent are explored. Methods: A phantom was made with HMDSO, water and mineral oil, each of which was prepared with oxygen and nitrogen, and was imaged in a 3T MRI system. The T1 properties were explored by the inversion recovery (TR=3000ms, TE=65ms) while varying the inversion time (TI), and also by the fast-field-echo (TR=2 ms, TE=2.8ms) while varying the flip angle (FA). T1rho was explored with a 5-pulse spin-locking technique (TR=5000ms, TE=10ms, spin-lock field=500Hz) while varying the spin-lock duration. T2 was explored with multi-shot TSE (TR=2500ms) while varying TE. Results: With the variable FA and TI, the signals of HMDSO with oxygen and nitrogen change in a similar way and do not respond well by the change of oxygen level, which confirms the large T1 value of HMDSO. The T1rho and T2, however, have a better sensitivity. Conclusion: For the possible pre-clinical hypoxia MRI agent (HMDSO), the detection of T1 (or R1) changes may be more challenging than the detection of other relaxation properties, particularly T2, as the oxygen level changes.« less

  15. Preparation of W and N, S-codoped titanium dioxide with enhanced photocatalytic activity under visible light irradiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huo, Rui; Yang, Jing-Yu; Liu, You-Qin

    2016-04-15

    Highlights: • W, N, S codoped TiO{sub 2} nanoparticles were synthesized by precipitation-impregnation method. • New linkages N–Ti–O, Ti–O–S and Ti–O–W were formed. • The activity of 0.011W, 0.030(N,S)-TiO{sub 2} is 10 times higher than that of TiO{sub 2}. • The doping enhanced visible light absorbance and accelerated the charge carrier separation. - Abstract: In this work, the preparation and physiochemical characterization of tungsten, nitrogen and sulfur codoping TiO{sub 2} photocatalysts (W, N, S-TiO{sub 2}) was undertaken. W, N, S-TiO{sub 2} nanoparticles were synthesized via the precipitation-impregnation method. To investigate the structural, optical, and electronic properties, the as-prepared W, N,more » S-TiO{sub 2} photocatalysts were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet-visible diffuse reflection spectrum (DRS). W, N, S-TiO{sub 2} samples showed photo-absorption in the visible light region and higher visible light photocatalytic activity than TiO{sub 2}. 0.011W, 0.030(N, S)-TiO{sub 2} exhibited the highest visible light photocatalytic activity, and the photocatalyic degradation activity of 0.011W,0.030(N,S)-TiO{sub 2} is nearly 10 times higher than that of TiO{sub 2}. Compared with the undoped TiO{sub 2}, the improved photocatalytic activity of W, N, S-TiO{sub 2} samples under visible light irradiation is attributed to the increase of the visible light absorption and the reduction in photogenerated electron-hole recombination.« less

  16. Study on the preparation process of cross-linked porous cassava starch

    NASA Astrophysics Data System (ADS)

    Yin, Xiulian; You, Qinghong; Wan, Miaomiao; Zhang, Xuejuan; Dai, Chunhua

    2017-04-01

    Using cassava starch as raw material, preparation process of porous cross-linked cassava starch was studied. Using TSTP as cross-linking agents, Orthogonal design was applied for the optimization of cross-linked porous starch preparation process. The results showed that the opitmal conditions of cross-linked porous cassava starch were as follows: reaction temperature 45°C, reaction time 20 h, 1% of the amount of the enzyme, the enzyme ratio of 1:5, pH 5.50, substrate concentration of 40%.

  17. Preservice Teachers as Change Agents: Going the Extra Mile in Service-Learning Experiences

    ERIC Educational Resources Information Center

    Marchel, Carol A.; Shields, Carol; Winter, Linda

    2011-01-01

    Educational psychologists involved in teacher education are expected to develop professional teacher dispositions of preservice students. The professional disposition "teacher as change agent" is used to frame actions in service-learning field experiences in a teacher preparation program. Preservice teacher service-learning journals, self-ratings,…

  18. Integration of Gas Chromatography Mass Spectrometry Methods for Differentiating Ricin Preparation Methods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wunschel, David S.; Melville, Angela M.; Ehrhardt, Christopher J.

    2012-05-17

    The investigation of crimes involving chemical or biological agents is infrequent, but presents unique analytical challenges. The protein toxin ricin is encountered more frequently than other agents and is found in the seeds of the castor plant Ricinus communis. Typically, the toxin is extracted from castor seeds utilizing a variety of different recipes that result in varying purity of the toxin. Moreover, these various purification steps can also leave or differentially remove a variety of exogenous and endogenous residual components with the toxin that may indicate the type and number of purification steps involved. We have applied three gas chromatographicmore » - mass spectrometric (GC-MS) based analytical methods to measure the variation in seed carbohydrates and castor oil ricinoleic acid as well as the presence of solvents used for purification. These methods were applied to the same samples prepared using four previously identified toxin preparation methods starting from four varieties of castor seeds. The individual data sets for seed carbohydrate profiles, ricinoleic acid or acetone amount each provided information capable of differentiating different types of toxin preparations across seed types. However, the integration of the data sets using multivariate factor analysis provided a clear distinction of all samples based on the preparation method and independent of the seed source. In particular the abundance of mannose, arabinose, fucose, ricinoleic acid and acetone were shown to be important differentiating factors. These complementary tools provide a more confident determination of the method of toxin preparation.« less

  19. [Alkylating agents].

    PubMed

    Pourquier, Philippe

    2011-11-01

    With the approval of mechlorethamine by the FDA in 1949 for the treatment of hematologic malignancies, alkylating agents are the oldest class of anticancer agents. Even though their clinical use is far beyond the use of new targeted therapies, they still occupy a major place in specific indications and sometimes represent the unique option for the treatment of refractory diseases. Here, we are reviewing the major classes of alkylating agents and their mechanism of action, with a particular emphasis for the new generations of alkylating agents. As for most of the chemotherapeutic agents used in the clinic, these compounds are derived from natural sources. With a complex but original mechanism of action, they represent new interesting alternatives for the clinicians, especially for tumors that are resistant to conventional DNA damaging agents. We also briefly describe the different strategies that have been or are currently developed to potentiate the use of classical alkylating agents, especially the inhibition of pathways that are involved in the repair of DNA lesions induced by these agents. In this line, the development of PARP inhibitors is a striking example of the recent regain of interest towards the "old" alkylating agents.

  20. N-Picolyl Derivatives of Kemp’s Triamine as Potential Antitumor Agents: A Preliminary Investigation

    PubMed Central

    Regino, Celeste Aida S.; Torti, Suzy V.; Ma, Rong; Yap, Glenn P.A.; Kreisel, Kevin A.; Torti, Frank M.; Planalp, Roy P.; Brechbiel, Martin W.

    2008-01-01

    Pre-organized tripodal ligands such as the N-picolyl derivatives of cis,cis-1,3,5-triamino-cis,cis-1,3,5-trimethylcyclohexane (Kemp’s triamine) were prepared as analogs to N,N’,N”- tris(2-pyridylmethyl)-cis,cis-1,3,5-triaminocyclohexane (tachpyr) in hopes of enhancing the rate of formation and stability of the metal complexes. A tricyclic bisaminal was formed via the reduction of the Schiff base while the tri(picolyl) derivative was synthesized via reductive amination of pyridine carboxaldehyde. Their cytotoxicities to the HeLa cell line were evaluated and directly compared to tachpyr and N,N’,N”- tris(2-pyridylmethyl)-tris(2-aminoethyl)amine (trenpyr). Results indicate that N,N’,N”-tris(2-pyridylmethyl)-cis,cis-1,3,5-triamino-cis,cis-1,3,5-trimethylcyclohexane (Kemp’s pyr) exhibits cytotoxic activity against the HeLa cancer cell line comparable to tachpyr (IC50 ~ 8.0 µM). Both Kemp’s pyr and tachpyr show higher cytotoxic activity over the aliphatic analogue of trenpyr (IC50 ~ 14 µM) suggesting that the major contributor to the activity is the ligand’s ability to form a stable and tight complex and that the equatorial/axial equilibrium impacting the complex formation for the cyclohexane-based ligands is not significant. PMID:16335923

  1. Rheological characterization of modified foodstuffs with food grade thickening agents

    NASA Astrophysics Data System (ADS)

    Reyes-Ocampo, I.; Aguayo-Vallejo, JP; Ascanio, G.; Córdova-Aguilar, MS

    2017-01-01

    This work describes a rheological characterization in terms of shear and extensional properties of whole milk, modified with food grade thickening agents (xanthan and carboxymethyl cellulose) with the purpose of being utilized in dysphagia treatment. Shear viscosity of the thickened fluids (2% wt. of xanthan and CMC) were measured in a stress-controlled rheometer and for extensional viscosity, a custom-built orifice flowmeter was used, with elongation rates from 20 to 3000 s-1. Such elongation-rate values represent the entire swallowing process, including the pharyngeal and esophageal phases. The steady-state shear and extensional flow curves were compared with the flow curve of a pudding consistency BaSO4 suspension (α=05), typically used as a reference fluid for the specialized commercial dysphagia products. The modified fluids presented non-Newtonian behavior in both, shear and extensional flows, and the comparison with the reference fluid show that the thickened milk prepared here, can be safely used for consumption by patients with severe dysphagia.

  2. Identification and evaluation of agents isolated from traditionally used herbs against Ophiophagus hannah venom.

    PubMed

    Salama, R; Sattayasai, J; Gande, A K; Sattayasai, N; Davis, M; Lattmann, E

    2012-02-01

    The aim of this study was firstly to identify active molecules in herbs, that are traditionally used for the treatment of snake bite, such as Curcuma antinaia, Curcuma contravenenum, Andrographis paniculata, and Tanacetum parthenium; secondly to test similar structurally related molecules and finally to prepare and evaluate an efficient formulation against Ophiophagus hannah venom intoxification. Three labdane based compounds, including labdane dialdehyde, labdane lactone, and labdane trialdehyde and two lactones including 14-deoxy-11,12-didehydroandrographolide and parthenolide were isolated by column chromatography and characterised. Using the isolated rat phrenic nerve-hemidiaphragm preparation, the antagonistic effect of crude extracts, isolated compounds and prepared formulations were measured in vitro on the inhibition of the neuromuscular transmission. Inhibition on muscle contraction, produced by the 5 μg/mL venom, was reversed by test agents in organ bath preparations. A labdane trialdehyde, isolated from C. contravenenum, was identified as the best antagonising agent in the low micromolar range. Tests on formulations of the most potent C. contravenenum extract showed, that the suppository with witepsol H15 was an effective medicine against O. hannah venom. This study elucidated the active compounds, accounting for the antivenin activity of traditionally used herbs and suggested the most suitable formulation, which may help to develop potent medicines for the treatment of snake bite in the future.

  3. Effect of S-doping on structural, optical and electrochemical properties of vanadium oxide thin films prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Mousavi, M.; Kompany, A.; Shahtahmasebi, N.; Bagheri-Mohagheghi, M.-M.

    2013-12-01

    In this research, S-doped vanadium oxide thin films, with doping levels from 0 to 40 at.%, are prepared by spray pyrolysis technique on glass substrates. For electrochemical measurements, the films were deposited on florin-tin oxide coated glass substrates. The effect of S-doping on structural, electrical, optical and electrochemical properties of vanadium oxide thin films was studied. The x-ray diffractometer analysis indicated that most of the samples have cubic β-V2O5 phase structure with preferred orientation along [200]. With increase in the doping levels, the structure of the samples tends to be amorphous. The scanning electron microscopy images show that the structure of the samples is nanobelt-shaped and the width of the nanobelts decreases from nearly 100 to 40 nm with increase in the S concentration. With increase in the S-doping level, the sheet resistance and the optical band gap increase from 940 to 4015 kΩ/square and 2.41 to 2.7 eV, respectively. The cyclic voltammogram results obtained for different samples show that the undoped sample is expanded and the sample prepared at 20 at.% S-doping level has sharper anodic and cathodic peaks.

  4. Preparation and Quality Control of 68Ga-Citrate for PET Applications

    PubMed Central

    Aghanejad, Ayuob; Jalilian, Amir Reza; Ardaneh, Khosro; Bolourinovin, Fatemeh; Yousefnia, Hassan; Samani, Ali Bahrami

    2015-01-01

    Objective(s): In nuclear medicine studies, gallium-68 (8Ga) citrate has been recently known as a suitable infection agent in positron emission tomography (PET). In this study, by applying an in-house produced 68Ge/68Ga generator, a simple technique for the synthesis and quality control of 68Ga-citrate was introduced; followed by preliminary animal studies. Methods: 68GaCl3 eluted from the generator was studied in terms of quality control factors including radiochemical purity (assessed by HPLC and RTLC), chemical purity (assessed by ICP-EOS), radionuclide purity (evaluated by HPGe), and breakthrough. 68Ga-citrate was prepared from eluted 68GaCl3 and sodium citrate under various reaction conditions. Stability of the complex was evaluated in human serum for 2 h at 370C, followed by biodistribution studies in rats for 120 min. Results: 68Ga-citrate was prepared with acceptable radiochemical purity (>97 ITLC and >98% HPLC), specific activity (4-6 GBq/mM), chemical purity (Sn, Fe<0.3 ppm and Zn<0.2 ppm) within 15 min at 500C. The biodistribution of 68Ga-citrate was consistent with former reports up to 120 minutes. Conclusion: This study demonstrated the possible in-house preparation and quality control of 68Ga-citrate, using a commercially available 68Ge/68Ga generator for PET imaging throughout the country. PMID:27408889

  5. Enhanced hydrogen peroxide release from macrophages stimulated with streptococcal preparation OK-432.

    PubMed Central

    Saito, H; Tomioka, H

    1979-01-01

    Wheat germ lectin was found to be a potent triggering agent for hydrogen peroxide release from mouse peritoneal macrophages. Macrophages stimulated by intraperitoneal injection of OK-432, a lyophilized attenuated streptococcal preparation, were highly responsive to wheat germ lectin. PMID:546795

  6. Enhancement of anion-exchange chromatography of DNA using compaction agents

    NASA Technical Reports Server (NTRS)

    Murphy, Jason C.; Fox, George E.; Willson, Richard C.

    2003-01-01

    The use of adsorptive chromatography for preparative nucleic acid separations is often limited by low capacity. The possibility that the adsorbent surface area sterically accessible to nucleic acid molecules could be increased by reducing their radius of gyration with compaction agents has been investigated. The equilibrium adsorption capacity of Q Sepharose anion-exchange matrix for plasmid DNA at 600 mM NaCl was enhanced by up to ca. 40% in the presence of 2.5 mM spermine. In addition, compaction agent selectivity has been demonstrated. Spermine, for example, enhances the adsorption of both plasmid and genomic DNA, spermidine enhances binding only of plasmid, and hexamine cobalt enhances only the binding of genomic DNA. Compaction may be generally useful for enhancing adsorptive separations of nucleic acids.

  7. Development of piperic acid derivatives from Piper nigrum as UV protection agents.

    PubMed

    Choochana, Piyapong; Moungjaroen, Jirapan; Jongkon, Nathjanan; Gritsanapan, Wandee; Tangyuenyongwatana, Prasan

    2015-04-01

    There is a need for the discovery of novel natural and semi-synthetic sunscreen that is safe and effective. Piperine has a UV absorption band of 230-400 nm with high molar absorptivity. This compound has a high potential to be developed to sunscreen. This study develops new UV protection compounds from piperine by using chemical synthesis. Piperine was isolated from Piper nigrum L. (Piperaceae) fruits, converted to piperic acid by alkaline hydrolysis, and prepared as ester derivatives by chemical synthesis. The piperate derivatives were prepared as 5% o/w emulsion, and the SPF values were evaluated. The best compound was submitted to cytotoxicity test using MTT assay. Piperic acid was prepared in 86.96% yield. Next, piperic acid was reacted with alcohols using Steglich reaction to obtain methyl piperate, ethyl piperate, propyl piperate, isopropyl piperate, and isobutyl piperate in 62.39-92.79% yield. All compounds were prepared as 5% oil in water emulsion and measured its SPF and UVA/UVB values using an SPF-290S analyzer. The SPF values (n = 6) of the piperate derivatives were 2.68 ± 0.17, 8.89 ± 0.46, 6.86 ± 0.91, 16.37 ± 1.8, and 9.68 ± 1.71. The UVA/UVB ratios of all compounds ranged from 0.860 to 0.967. Cytotoxicity of isopropyl piperate was evaluated using human skin fibroblast cells and the IC50 was equal to 120.2 μM. From the results, isopropyl piperate is an outstanding compound that can be developed into a UV protection agent.

  8. Thermoelectric SnS and SnS-SnSe solid solutions prepared by mechanical alloying and spark plasma sintering: Anisotropic thermoelectric properties

    PubMed Central

    Asfandiyar; Wei, Tian-Ran; Li, Zhiliang; Sun, Fu-Hua; Pan, Yu; Wu, Chao-Feng; Farooq, Muhammad Umer; Tang, Huaichao; Li, Fu; Li, Bo; Li, Jing-Feng

    2017-01-01

    P–type SnS compound and SnS1−xSex solid solutions were prepared by mechanical alloying followed by spark plasma sintering (SPS) and their thermoelectric properties were then studied in different compositions (x = 0.0, 0.2, 0.5, 0.8) along the directions parallel (//) and perpendicular (⊥) to the SPS–pressurizing direction in the temperature range 323–823 Κ. SnS compound and SnS1−xSex solid solutions exhibited anisotropic thermoelectric performance and showed higher power factor and thermal conductivity along the direction ⊥ than the // one. The thermal conductivity decreased with increasing contents of Se and fell to 0.36 W m−1 K−1 at 823 K for the composition SnS0.5Se0.5. With increasing selenium content (x) the formation of solid solutions substantially improved the electrical conductivity due to the increased carrier concentration. Hence, the optimized power factor and reduced thermal conductivity resulted in a maximum ZT value of 0.64 at 823 K for SnS0.2Se0.8 along the parallel direction. PMID:28240324

  9. Thermoelectric SnS and SnS-SnSe solid solutions prepared by mechanical alloying and spark plasma sintering: Anisotropic thermoelectric properties.

    PubMed

    Asfandiyar; Wei, Tian-Ran; Li, Zhiliang; Sun, Fu-Hua; Pan, Yu; Wu, Chao-Feng; Farooq, Muhammad Umer; Tang, Huaichao; Li, Fu; Li, Bo; Li, Jing-Feng

    2017-02-27

    P-type SnS compound and SnS 1-x Se x solid solutions were prepared by mechanical alloying followed by spark plasma sintering (SPS) and their thermoelectric properties were then studied in different compositions (x = 0.0, 0.2, 0.5, 0.8) along the directions parallel (//) and perpendicular (⊥) to the SPS-pressurizing direction in the temperature range 323-823 Κ. SnS compound and SnS 1-x Se x solid solutions exhibited anisotropic thermoelectric performance and showed higher power factor and thermal conductivity along the direction ⊥ than the // one. The thermal conductivity decreased with increasing contents of Se and fell to 0.36 W m -1  K -1 at 823 K for the composition SnS 0.5 Se 0.5 . With increasing selenium content (x) the formation of solid solutions substantially improved the electrical conductivity due to the increased carrier concentration. Hence, the optimized power factor and reduced thermal conductivity resulted in a maximum ZT value of 0.64 at 823 K for SnS 0.2 Se 0.8 along the parallel direction.

  10. Cognitive conflict without explicit conflict monitoring in a dynamical agent.

    PubMed

    Ward, Robert; Ward, Ronnie

    2006-11-01

    We examine mechanisms for resolving cognitive conflict in an embodied, situated, and dynamic agent, developed through an evolutionary learning process. The agent was required to solve problems of response conflict in a dual-target "catching" task, focusing response on one of the targets while ignoring the other. Conflict in the agent was revealed at the behavioral level in terms of increased latencies to the second target. This behavioral interference was correlated to peak violations of the network's stable state equation. At the level of the agent's neural network, peak violations were also correlated to periods of disagreement in source inputs to the agent's motor effectors. Despite observing conflict at these numerous levels, we did not find any explicit conflict monitoring mechanisms within the agent. We instead found evidence of a distributed conflict management system, characterized by competitive sources within the network. In contrast to the conflict monitoring hypothesis [Botvinick, M. M., Braver, T. S., Barch, D. M., Carter, C. S., & Cohen, J. D. (2001). Conflict monitoring and cognitive control. Psychological Review, 108(3), 624-652], this agent demonstrates that resolution of cognitive conflict does not require explicit conflict monitoring. We consider the implications of our results for the conflict monitoring hypothesis.

  11. Application of cow milk-derived carbon dots/Ag NPs composite as the antibacterial agent

    NASA Astrophysics Data System (ADS)

    Han, Shuai; Zhang, He; Xie, Yujie; Liu, Liangliang; Shan, Changfu; Li, Xiangkai; Liu, Weisheng; Tang, Yu

    2015-02-01

    Cow milk-derived carbon dots (CMCDs) were prepared by hydrothermal treatment of cow milk, and the as-prepared CMCDs were further extracted by ethyl acetate to obtain amphiphilic CMCDs (ACMCDs). Using the ACMCDs both as a reducing agent and a template, the ACMCDs-supported silver nanoparticles (ACMCD-Ag nanocomposites) were prepared, which showed good biocidal effect on both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacterias. After that, a novel ACMCD-Ag/polymethylmethacrylate nanocomposite antibacterial film was fabricated by solvent casting method. Due to the excellent antibacterial, light admitting, and flexible properties, the nanocomposite antibacterial film is considered to be of great potential in applications.

  12. Oxyresveratrol and ascorbic acid O/W microemulsion: Preparation, characterization, anti-isomerization and potential application as antibrowning agent on fresh-cut lotus root slices.

    PubMed

    He, Jianfei; Zhu, Qin; Dong, Xue; Pan, Hongyang; Chen, Jie; Zheng, Zong-Ping

    2017-01-01

    The purpose of this study is to prepare an oxyresveratrol (Oxy) microemulsion (ME) with improved Oxy's solubility and stability and to investigate its antibrowning effects on fresh-cut lotus root slices. The formula of OxyME consisted of ethyl butyrate, Tween 80, PEG400, and water with w/w of 4%, 10.67%, 5.33%, and 80%, respectively. Encapsulating Oxy into OxyME greatly increased its solubility and stability compared with that of in water. Strong antibrowning effects were observed on fresh-cut lotus root slices treated with OxyME, even better than 4-hexylresorcinol. The addition of ascorbic acid (VC) into OxyME greatly improved the Oxy stability in long-term storage and antibrowning effects on fresh-cut lotus root slices. However, the simultaneous addition of calcium chloride and VC did not obviously improve the antibrowning effects compared with the addition of VC alone. These results indicated that Oxy+VCME may be suitable as an antibrowning agent for fresh-cut vegetables. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Preparation and isolation of dithiolene thiophosphoryl molecules as stable, protected forms of dithiolene ligands.

    PubMed

    Arumugam, Kuppuswamy; Bollinger, James E; Fink, Mark; Donahue, James P

    2007-04-16

    The reaction of P4S10 with acyloins, RC(O)CH(OH)R, in refluxing dioxane, followed by the addition of alkylating agents, forms dithiolene thiophosphoryl thiolate compounds, (R2C2S2)P(S)(SR'), which are readily isolated and purified. The compounds that have been prepared and identified spectroscopically are those with R = p-anisyl, R' = Me (1); R = p-anisyl, R' = Bz (2); R = Ph, R' = Me (4); R = Et, R' = Bz (5). Compounds 1, 2, and 4 were structurally characterized by X-ray crystallography and found to possess a tetrahedral coordination geometry about the phosphorus atom, with overall Cs symmetry. In each case, the mirror plane bisects the dithiolene S-P-S chelate and contains the thiophosphoryl bond, which ranges in length from 1.9241(8) to 1.9361(7) A. The use of 2-(bromomethyl)naphthalene as organic electrophile in the P4S10/acyloin reaction produced bis(2-methylnaphthalenyl) disulfide as the only identifiable product. The substitution of Lawesson's reagent for P4S10 in reactions with acyloins produced deoxy acyloin rather than products resulting from chalcogen exchange. Compounds 1-2 and 4-5 are Group 5 analogues of 1,3-dithiol-2-ones, (R2C2S2)C=O, and undergo a similar hydrolysis in aqueous base to liberate ene-1,2-dithiolate dianions from which corresponding metal dithiolene complexes may be prepared. Deprotection of 1 in MeO-/MeOH, followed by the addition of NiCl2.6H2O and then I2, produces square planar [Ni(S2C2(C6H4-p-OCH3)2)2] (8) in 93% yield. A high-resolution structure of 8 (P) reveals dithiolene C-C and C-S bond lengths that are clearly indicative of the thionyl radical monoanionic nature of the ligand. The use of isolated (R2C2S2)P(S)(SR') compounds as a dithiolene ligand source for the preparation of metal dithiolene complexes offers the advantages of clean reactivity and high yield.

  14. Effect of mixing method on the mixing degree during the preparation of triturations.

    PubMed

    Nakamura, Hitoshi; Yanagihara, Yoshitsugu; Sekiguchi, Hiroko; Komada, Fusao; Kawabata, Haruno; Ohtani, Michiteru; Saitoh, Yukiya; Kariya, Satoru; Suzuki, Hiroshi; Uchino, Katsuyoshi; Iga, Tatsuji

    2004-03-01

    By using lactose colored with erythrocin, we investigated the effects of mixing methods on mixing degree during the preparation of trituration with a mortar and pestle. The extent of powder dilution was set to 4 to 64 fold in the experiments. We compared the results obtained by using two methods: (1) one-step mixing of powders after addition of diluents and (2) gradual mixing of powders after addition of diluents. As diluents, we used crystallized lactose and powdered lactose for the preparation of trituration. In the preparation of 64-fold trituration, an excellent degree of mixing was obtained, with CV values of less than 6.08%, for both preparation methods and for the two kinds of diluents. The mixing of two kinds of powders whose distributions of particle sizes were similar resulted in much better degree of mixing, with CV values of less than 3.0%. However, the concentration of principal agents in 64-fold trituration was reduced by 20% due to the adsorption of dye to the apparatus. Under conditions in which a much higher dilution rate and/or much better degree of dilution was required, it must be necessary to dilute powders with considering their physicality and to determine the concentrations of principal agents after the mixing.

  15. Global Village versus Culture Shock: The Recruitment and Preparation of Foreign Teachers for U. S. Urban Schools

    ERIC Educational Resources Information Center

    Dunn, Alyssa Hadley

    2011-01-01

    Though international teachers have been present in U.S. schools for decades, their recruitment for urban schools as a response to the supposed teacher shortage is a relatively new phenomenon with little research to support it. This study examines international teachers' recruitment and preparation for urban environments. Informed by classroom…

  16. Novel Treatment of Staphylococcus aureus Device-Related Infections Using Fibrinolytic Agents.

    PubMed

    Hogan, S; O'Gara, J P; O'Neill, E

    2018-02-01

    Staphylococcal infections involving biofilms represent a significant challenge in the treatment of patients with device-related infections. Staphylococcus aureus biofilms have been shown to be SaeRS regulated and dependent on the coagulase-catalyzed conversion of fibrinogen into fibrin on surfaces coated with human plasma. Here we investigated the treatment of staphylococcal biofilm device-related infections by digesting the fibrin biofilm matrix with and without existing antimicrobials. The fibrinolytic agents plasmin, streptokinase, and nattokinase, and TrypLE, a recombinant trypsin-like protease, were used to digest and treat S. aureus biofilms grown in vitro using in vivo -like static biofilm assays with and without antimicrobials. Cytotoxicity, the potential to induce a cytokine response in whole human blood, and the risk of induction of tolerance to fibrinolytic agents were investigated. A rat model of intravascular catheter infection was established to investigate the efficacy of selected fibrinolytic agents in vivo Under biomimetic conditions, the fibrinolytic agents effectively dispersed established S. aureus biofilms and, in combination with common antistaphylococcal antimicrobials, effectively killed bacterial cells being released from the biofilm. These fibrinolytic agents were not cytotoxic and did not affect the host immune response. The rat model of infection successfully demonstrated the activity of the selected fibrinolytic agents alone and in combination with antimicrobials on established biofilms in vivo TrypLE and nattokinase most successfully removed adherent cells from plasma-coated surfaces and significantly improved the efficacy of existing antimicrobials against S. aureus biofilms in vitro and in vivo These biofilm dispersal agents represent a viable future treatment option for S. aureus device-related infections. Copyright © 2018 American Society for Microbiology.

  17. Microencapsulation of Self Healing Agents for Corrosion Control Coatings

    NASA Technical Reports Server (NTRS)

    Jolley, S. T.; Li, W.; Buhrow, J. W.; Calle, L. M.

    2011-01-01

    Corrosion, the environmentally induced degradation of materials, is a very costly problem that has a major impact on the global economy. Results from a 2-year breakthrough study released in 2002 by the U.S. Federal Highway Administration (FHWA) showed that the total annual estimated direct cost associated with metallic corrosion in nearly every U.S. industry sector was a staggering $276 billion, approximately 3.1% of the nation's Gross Domestic Product (GOP). Corrosion protective coatings are widely used to protect metallic structures from the detrimental effects of corrosion but their effectiveness can be seriously compromised by mechanical damage, such as a scratch, that exposes the metallic substrate. The incorporation of a self healing mechanism into a corrosion control coating would have the potential to significantly increase its effectiveness and useful lifetime. This paper describes work performed to incorporate a number of microcapsule-based self healing systems into corrosion control coatings. The work includes the preparation and evaluation of self-healing systems based on curable epoxy, acrylate, and siloxane resins, as well as, microencapsulated systems based on passive, solvent born, healing agent delivery. The synthesis and optimization of microcapsule-based self healing systems for thin coating (less than 100 micron) will be presented.

  18. Carbon Nanoparticles decorated with cupric oxide Nanoparticles prepared by laser ablation in liquid as an antibacterial therapeutic agent

    NASA Astrophysics Data System (ADS)

    Khashan, Khawla S.; Jabir, Majid S.; Abdulameer, Farah A.

    2018-03-01

    Carbon nanoparticles (CNPs) decorated with cupric oxide nanoparticles (CuO NPs) were prepared by laser ablation in water, and their antibacterial activity was examined. X-ray diffraction measurements demonstrated the presence of carbon phases and different CuO phases, and results were confirmed by Fourier transform infrared analysis. Energy- Dispersive spectra showed the presence of C, O, and Cu in the final product. Transmission electron micrographs revealed that the CNPs were 10-80 nm in size and spherical; after being decorated with CuO NPs, particles became 5-50 nm in size and uniform in shape. The absorption spectrum of decorated Nanoparticles indicated the appearance of a new peak at 254-264 nm in addition to the fundamental peak at 228 nm. We then examined the antibacterial activity of the decorated CNPs for both gram-negative and -positive bacteria using the agar-well-diffusion method. The mode of action was determined using acridine orange-ethidium bromide staining to detect reactive oxygen species, and bacterial morphological change was studied by scanning electron microscopy. Results showed that CNPs decorated with 43% CuO NPs had the highest antibacterial activity for gram-positive bacteria. The CNPs acted on the cytoplasmic membrane and nucleic acid of bacteria, which led to a loss of cell-wall integrity, increased cell-wall permeability, and nucleic acid damage. The results offer a novel way to synthesis Carbon nanoparticles decorated with cupric oxide nanoparticles and could use them as novel antibacterial agent in future for pharmaceutical and biomedical applications.

  19. Thyroid Dysfunction from Antineoplastic Agents

    PubMed Central

    Larsen, P. Reed; Marqusee, Ellen

    2011-01-01

    Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%–50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient’s quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents. PMID:22010182

  20. Y-90-DOTA-hLL2: An Agent for Radioimmunotherapy of Non-Hodgkin's Lymphoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Griffiths, Gary L.; Govindan, Serengulam V.; Sharkey, Robert M.

    2003-01-01

    The goal of this work was to determine an optimal radioimmunotherapy agent for non-Hodgkin's lymphoma. We established the stability profile of yttrium-90-labeled humanized LL2 (hLL2) monoclonal antibody prepared with different chelating agents, and from these data estimated the improvement using the most stable yttrium-90 chelate-hLL2 complex. Methods: The complementary-determining region- (cdr)-grafted (humanized) anti-CD22 mAb, hLL2 (epratuzumab), was conjugated to derivatives of DTPA and 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA). The conjugates were labeled with Y-90 and tested against a 10,000-fold molar excess of free DTPA and against human serum. The conjugates were also labeled with Y-88 and compared for biodistribution in normal andmore » lymphoma xenograft-bearing athymic mice. In vivo data were analyzed for uptake of yttrium in bone and washed bone when either the DOTA or the Mx-DTPA chelates were used, and dosimetry calculations were made for each. Results: Y-90-DOTA -mAb were stable to either DTPA or serum challenge. DTPA complexes of hLL2 lost 3-4% of Y-90 (days 1-4) and 10-15% thereafter. In vivo, stability differences showed lower Y-90 uptake in bone using DOTA. Absorbed doses per 37 MBq (1 mCi) Y-90-mAb were 3555 and 5405 cGy for bone, and 2664 and 4524 cGy for washed-bone for 90Y-DOTA-hLL2 and 90Y-MxDTPA-hLL2, respectively, amounting to 52% and 69.8% increases in absorbed radiation doses for bone and washed-bone when switching from a DOTA to a Mx-DTPA chelate. Conclusion: Y-90-hLL2 prepared with the DOTA chelate represents a preferred agent for RAIT of non-Hodgkin's lymphoma, with an in vivo model demonstrating a large reduction in bone-deposited yttrium, as compared to yttrium-90-hLL2 agents prepared with open-chain DTPA-type chelating agents. Dosimetry suggests that this will result in a substantial toxicological advantage for a DOTA-based hLL2 conjugate.« less

  1. Incorporating BDI Agents into Human-Agent Decision Making Research

    NASA Astrophysics Data System (ADS)

    Kamphorst, Bart; van Wissen, Arlette; Dignum, Virginia

    Artificial agents, people, institutes and societies all have the ability to make decisions. Decision making as a research area therefore involves a broad spectrum of sciences, ranging from Artificial Intelligence to economics to psychology. The Colored Trails (CT) framework is designed to aid researchers in all fields in examining decision making processes. It is developed both to study interaction between multiple actors (humans or software agents) in a dynamic environment, and to study and model the decision making of these actors. However, agents in the current implementation of CT lack the explanatory power to help understand the reasoning processes involved in decision making. The BDI paradigm that has been proposed in the agent research area to describe rational agents, enables the specification of agents that reason in abstract concepts such as beliefs, goals, plans and events. In this paper, we present CTAPL: an extension to CT that allows BDI software agents that are written in the practical agent programming language 2APL to reason about and interact with a CT environment.

  2. Use of 2,5-dimethyl-2,5-hexane diamine as a curing agent for epoxy resins. [Patent application

    DOEpatents

    Rinde, J.A.; Newey, H.A.

    Primary diamines are prepared for use as a curing agent for epoxy resins. These curing agents can be used to form epoxy resin mixtures useful in filament winding and preimpregnated fiber molding and in formulating film adhesives, powder coatings and molding powders. The epoxy mixtures form for such uses a room temperature non-reacting, intermediate stable state which has a latent cross-linking capability.

  3. Poly(iohexol) nanoparticles as contrast agents for in vivo X-ray computed tomography imaging.

    PubMed

    Yin, Qian; Yap, Felix Y; Yin, Lichen; Ma, Liang; Zhou, Qin; Dobrucki, Lawrence W; Fan, Timothy M; Gaba, Ron C; Cheng, Jianjun

    2013-09-18

    Biocompatible poly(iohexol) nanoparticles, prepared through cross-linking of iohexol and hexamethylene diisocyanate followed by coprecipitation of the resulting cross-linked polymer with mPEG-polylactide, were utilized as contrast agents for in vivo X-ray computed tomography (CT) imaging. Compared to conventional small-molecule contrast agents, poly(iohexol) nanoparticles exhibited substantially protracted retention within the tumor bed and a 36-fold increase in CT contrast 4 h post injection, which makes it possible to acquire CT images with improved diagnosis accuracy over a broad time frame without multiple administrations.

  4. Chemical warfare agents.

    PubMed

    Kuca, Kamil; Pohanka, Miroslav

    2010-01-01

    Chemical warfare agents are compounds of different chemical structures. Simple molecules such as chlorine as well as complex structures such as ricin belong to this group. Nerve agents, vesicants, incapacitating agents, blood agents, lung-damaging agents, riot-control agents and several toxins are among chemical warfare agents. Although the use of these compounds is strictly prohibited, the possible misuse by terrorist groups is a reality nowadays. Owing to this fact, knowledge of the basic properties of these substances is of a high importance. This chapter briefly introduces the separate groups of chemical warfare agents together with their members and the potential therapy that should be applied in case someone is intoxicated by these agents.

  5. Surface Properties and Photocatalytic Activities of the Colloidal ZnS:Mn Nanocrystals Prepared at Various pH Conditions

    PubMed Central

    Heo, Jungho; Hwang, Cheong-Soo

    2015-01-01

    Water-dispersible ZnS:Mn nanocrystals (NC) were synthesized by capping the surface with mercaptoacetic acid (MAA) molecules at three different pH conditions. The obtained ZnS:Mn-MAA NC products were physically and optically characterized by corresponding spectroscopic methods. The UV-Visible absorption spectra and PL emission spectra showed broad peaks at 310 and 590 nm, respectively. The average particle sizes measured from the HR-TEM images were 5 nm, which were also supported by the Debye-Scherrer calculations using the X-ray diffraction (XRD) data. Moreover, the surface charges and the degrees of aggregation of the ZnS:Mn-MAA NCs were determined by electrophoretic and hydrodynamic light scattering methods, indicating formation of agglomerates in water with various sizes (50–440 nm) and different surface charge values accordingly the preparation conditions of the NCs (−7.59 to −24.98 mV). Finally, the relative photocatalytic activities of the ZnS:Mn-MAA NCs were evaluated by measuring the degradation rate of methylene blue (MB) molecule in a pseudo first-order reaction condition under the UV-visible light irradiation. As a result, the ZnS:Mn-MAA NC prepared at the pH 7 showed the best photo-degradation efficiency of the MB molecule with the first-order rate constant (kobs) of 2.0 × 10−3·min−1. PMID:28347105

  6. Hydrolysis of DFP and the Nerve Agent (S)-Sarin by DFPase Proceeds along Two Different Reaction Pathways: Implications for Engineering Bioscavengers

    PubMed Central

    2015-01-01

    Organophosphorus (OP) nerve agents such as (S)-sarin are among the most highly toxic compounds that have been synthesized. Engineering enzymes that catalyze the hydrolysis of nerve agents (“bioscavengers”) is an emerging prophylactic approach to diminish their toxic effects. Although its native function is not known, diisopropyl fluorophosphatase (DFPase) from Loligo vulgaris catalyzes the hydrolysis of OP compounds. Here, we investigate the mechanisms of diisopropylfluorophosphate (DFP) and (S)-sarin hydrolysis by DFPase with quantum mechanical/molecular mechanical umbrella sampling simulations. We find that the mechanism for hydrolysis of DFP involves nucleophilic attack by Asp229 on phosphorus to form a pentavalent intermediate. P–F bond dissociation then yields a phosphoacyl enzyme intermediate in the rate-limiting step. The simulations suggest that a water molecule, coordinated to the catalytic Ca2+, donates a proton to Asp121 and then attacks the tetrahedral phosphoacyl intermediate to liberate the diisopropylphosphate product. In contrast, the calculated free energy barrier for hydrolysis of (S)-sarin by the same mechanism is highly unfavorable, primarily because of the instability of the pentavalent phosphoenzyme species. Instead, simulations suggest that hydrolysis of (S)-sarin proceeds by a mechanism in which Asp229 could activate an intervening water molecule for nucleophilic attack on the substrate. These findings may lead to improved strategies for engineering DFPase and related six-bladed β-propeller folds for more efficient degradation of OP compounds. PMID:24720808

  7. Investigation of a potential macromolecular MRI contrast agent prepared from PPI (G = 2, polypropyleneimine, generation 2) dendrimer bifunctional chelates

    NASA Astrophysics Data System (ADS)

    Wang, Jianxin Steven

    The long-term objective is to develop magnetic resonance (MR) contrast agents that actively and passively target tumors for diagnosis and therapy. Many diagnostic imaging techniques for cancer lack specificity. A dendrimer based magnetic resonance imaging contrast agent has been developed with large proton relaxation enhancements and high molecular relaxivities. A new type of linear dendrimer based MRI contrast agent that is built from the polypropyleneimine and polyamidoamine dendrimers in which free amines have been conjugated to the chelate DTPA, which further formed the complex with Gadolinium (Gd) was studied. The specific research goals were to test the hypothesis that a linear chelate with macromolecular agents can be used in vitro and in vivo. This work successfully examined the adequacy and viability of the application for this agent in vitro and in vivo. A small animal whole body counter was designed and constructed to allow us to monitor biodistribution and kinetic mechanisms using a radioisotope labeled complex. The procedures of metal labeling, separation and purification have been established from this work. A biodistribution study has been performed using radioisotope induced organ/tissue counting and gamma camera imaging. The ratio of percentage of injected dose per gram organ/tissue for kidney and liver is 3.71 from whole body counter and 3.77 from the gamma camera. The results suggested that retention of Gd (III) is too high and a more kinetically stable chelate should be developed. The pharmacokinetic was evaluated in the whole animal model with the whole body clearance, and a kinetics model was developed. The pharmacokinetic results showed a bi-exponential decay in the animal model with two component excretion constants 1.43e(-5) and 0.0038511, which give half-lives of 3 hours and 33.6 days, respectively. Magnetic resonance imaging of this complex resulted in a 52% contrast enhancement in the rat kidney following the agents' administration in

  8. Anti-cancer agents based on 6-trifluoromethoxybenzimidazole derivatives and method of making

    DOEpatents

    Gakh, Andrei A.; Vovk, Mykhaylo V.; Mel'nychenko, Nina V.; Sukach, Volodymyr A.

    2012-08-14

    The present disclosure relates to novel compounds having the structural Formulas (1a,1b), stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof as chemotherapy agents for treating of cancer, particularly androgen-independent prostate cancer. The disclosure also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  9. Anti-cancer agents based on 6-trifluoromethoxybenzimidazole derivatives and method of making

    DOEpatents

    Gakh, Andrei A; Vovk, Mykhaylo V; Mel& #x27; nychenko, Nina V; Sukach, Volodymyr A

    2012-10-23

    The present disclosure relates to novel compounds having the structural Formulas (1a,1b), stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof as chemotherapy agents for treating of cancer, particularly androgen-independent prostate cancer. The disclosure also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  10. Measurement of drug facilitated sexual assault agents in simulated sweat by ion mobility spectrometry.

    PubMed

    Demoranville, Leonard T; Verkouteren, Jennifer R

    2013-03-15

    Ion mobility spectrometry has found widespread use for the detection of explosives and illicit drugs. The technique offers rapid results with high sensitivity and little sample preparation. As such, it is well suited for field deployed screening settings. Here the response of ion mobility spectrometers for three drug-facilitated sexual assault (DFSA) agents - flunitrazepam, ketamine, and MDMA - and related metabolites has been studied in the presence of a simulated sweat. While all three DFSA agents present certain challenges for qualitative identification, IMS can provide useful information to guide the early treatment and investigation of sexual assault cases. Used as a presumptive test, the identification of DFSA agents would later require confirmatory analysis by other techniques. Published by Elsevier B.V.

  11. Biological Agents

    MedlinePlus

    ... E-Tools Safety and Health Topics / Biological Agents Biological Agents This page requires that javascript be enabled ... 202) 693-2300 if additional assistance is required. Biological Agents Menu Overview In Focus: Ebola Frederick A. ...

  12. Preparation of Hemoglobin-Containing Microcapsules.

    DTIC Science & Technology

    1982-04-01

    L -i2 801 PREPARRTION OF HEMOGLOBIN-CONTAINING MICROCAPSULES (U) i/i I SRI INTERNATIONAL MENLO PRK CA Z REYES APR 82 UNLSSFE SRI1-2254-2 DRMDi,7-8@-C...R oI• _ AD I PREPARATION OF HEMOGLOBIN- /2 o ) CONTAINING MICROCAPSULES . 00 ANNUAL AND FINAL REPORT ZOILA REYES, Ph.D. APRIL 1982 Supported by U.S...1/31/82) PREPARATION OF HEMOGLOBIN-CONTAINING MICROCAPSULES 6. PERFORMING ORG. REPOR’ NUMBER 2254-2 7. AUTHOR(s) 8. CONTRACT OR GRANT NUMBER(s) Zoila

  13. Garlic-derived S-allylmercaptocysteine is a novel in vivo antimetastatic agent for androgen-independent prostate cancer.

    PubMed

    Howard, Edward W; Ling, Ming-Tat; Chua, Chee Wai; Cheung, Hiu Wing; Wang, Xianghong; Wong, Yong Chuan

    2007-03-15

    There is epidemiologic evidence that high garlic consumption decreases the incidence of prostate cancer, and compounds isolated from garlic have been shown to have cancer-preventive and tumor-suppressive effects. Recent in vitro studies in our laboratory have shown that garlic-derived organosulfur compound S-allylmercaptocysteine suppresses invasion and cell motility of androgen-independent prostate cancer cells via the up-regulation of cell-adhesion molecule E-cadherin. S-allylmercaptocysteine is therefore a potential antimetastatic drug with broad clinical applications that we tested in vivo for the first time in this study. We used a newly established fluorescent orthotopic androgen-independent prostate cancer mouse model to assess the ability of S-allylmercaptocysteine to inhibit tumor growth and dissemination. We showed that oral S-allylmercaptocysteine not only inhibited the growth of primary tumors by up to 71% (P < 0.001) but also reduced the number of lung and adrenal metastases by as much as 85.5% (P = 0.001) without causing notable toxicity. This metastatic suppression was accompanied by a 91% reduction of viable circulating tumor cells (P = 0.041), suggesting that S-allylmercaptocysteine prevents dissemination by decreasing tumor cell intravasation. Our results provide in vivo evidence supporting the potential use of S-allylmercaptocysteine as an E-cadherin up-regulating antimetastatic agent for the treatment of androgen-independent prostate cancer. This is the first report of the in vivo antimetastatic properties of garlic, which may also apply to other cancer types.

  14. An Advanced Computational Approach to System of Systems Analysis & Architecting Using Agent-Based Behavioral Model

    DTIC Science & Technology

    2012-09-30

    System N Agent « datatype » SoS Architecture -Receives Capabilities1 -Provides Capabilities1 1 -Provides Capabilities1 1 -Provides Capabilities1 -Updates 1...fitness, or objective function. The structure of the SoS Agent is depicted in Figure 10. SoS Agent Architecture « datatype » Initial SoS...Architecture «subsystem» Fuzzy Inference Engine FAM « datatype » Affordability « datatype » Flexibility « datatype » Performance « datatype » Robustness Input Input

  15. About the Chemopreventive Agent Development Research Group | Division of Cancer Prevention

    Cancer.gov

    The Chemopreventive Agent Development Research Group promotes and supports research on early chemopreventive agent development, from preclinical studies to phase I clinical trials. The group’s projects aim to identify and develop prevention agents with the potential to block, reverse, or delay the early stages of cancer. The overarching goal is to determine positive and

  16. Synthesis of Mn-doped ZnS architectures in ternary solution and their optical properties

    NASA Astrophysics Data System (ADS)

    Wang, Xinjuan; Zhang, Qinglin; Zou, Bingsuo; Lei, Aihua; Ren, Pinyun

    2011-10-01

    Mn-doped ZnS sea urchin-like architectures were fabricated by a one-pot solvothermal route in a ternary solution made of ethylenediamine, ethanolamine and distilled water. The as-prepared products were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and photoluminescence spectra (PL). It was demonstrated that the as-prepared sea urchin-like architectures with diameter of 0.5-1.5 μm were composed of nanorods, possessing a wurtzite structures. The preferred growth orientation of nanorods was found to be the [0 0 2] direction. The PL spectra of the Mn-doped ZnS sea urchin-like architectures show a strong orange emission at 587 nm, indicating the successful doping of Mn 2+ ions into ZnS host. Ethanolamine played the role of oriented-assembly agent in the formation of sea urchin-like architectures. A possible growth mechanism was proposed to explain the formation of sea urchin-like architectures.

  17. Preparation of polyaniline/PbS core-shell nano/microcomposite and its application for photocatalytic H2 electrogeneration from H2O.

    PubMed

    Rabia, Mohamed; Mohamed, H S H; Shaban, Mohamed; Taha, S

    2018-01-18

    Lead sulfide (PbS) and polyaniline (PANI) nano/microparticles were prepared. Then, PANI/PbS core-shell nano/microcomposites (I, II, and III) were prepared by oxidative polymerization of different aniline concentrations (0.01, 0.03, and 0.05 M), respectively, in the presence of 0.05 M PbS. FT-IR, XRD, SEM, HR-TEM, and UV-Vis analyses were carried out to characterize the samples. From the FT-IR data, there are redshifts in PbS and PANI nano/microparticles bands in comparison with PANI/PbS nano/microcomposites. The average crystallite sizes of PANI/PbS core-shell nano/microcomposites (I, II, and III) from XRD analyses were 46.5, 55, and 42.16 nm, respectively. From the optical analyses, nano/microcomposite (II) has the optimum optical properties with two band gaps values of 1.41 and 2.79 eV. Then, the nano/microcomposite (II) membrane electrode supported on ITO glass was prepared and applied on the photoelectrochemical (PEC) H 2 generation from H 2 O. The characteristics current-voltage and current-time behaviors were measured at different wavelengths from 390 to 636 nm. Also, the incident photon-to-current conversion efficiency (IPCE) under monochromatic illumination condition was calculated. The optimum values for IPCE were 36.5 and 35.2% at 390 and 405 nm, respectively. Finally, a simple mechanism for PEC H 2 generation from H 2 O using the nano/microcomposite (II) membrane electrode was mentioned.

  18. One-pot mass preparation of MoS2/C aerogels for high-performance supercapacitors and lithium-ion batteries.

    PubMed

    Zhang, Yan; He, Ting; Liu, Guanglei; Zu, Lianhai; Yang, Jinhu

    2017-07-20

    In this paper, we report the successful design and synthesis of a hierarchically porous MoS 2 /C composite aerogel by simple one-pot mass preparation. The synthesis involves the in situ formation of MoS 2 nanosheets on agarose molecular chains, the gelation of MoS 2 -deposited agarose monomers to generate a composite hydrogel, and in situ transformation of the composite hydrogel into a MoS 2 /C composite aerogel through carbonization. This composite aerogel can be used as a high-performance electrode material for supercapacitors and lithium-ion batteries. When tested as a supercapacitor electrode, it achieves a high specific capacitance of 712.6 F g -1 at 1 A g -1 and 97.3% capacity retention after 13 000 cycles at 6 A g -1 . In addition, as a lithium-ion battery electrode, it exhibits a superior rate capability (653.2 mA h g -1 at 0.1 A g -1 and 334.5 mA h g -1 at 5.0 A g -1 ) and an ultrahigh capacity retention of nearly 100% after 1000 cycles at 1 A g -1 . These performances may be ascribed to the unique structure of the MoS 2 /C composite aerogel, such as hierarchical pores, (002) plane-expanded MoS 2 and interconnected carbon networks embedded uniformly with MoS 2 nanosheets. This work may provide a general and simple approach for mass preparation of composite aerogel materials and pave the way for promising materials applied in both supercapacitors and lithium-ion batteries.

  19. Growth of different phases and morphological features of MnS thin films by chemical bath deposition: Effect of deposition parameters and annealing

    NASA Astrophysics Data System (ADS)

    Hannachi, Amira; Maghraoui-Meherzi, Hager

    2017-03-01

    Manganese sulfide thin films have been deposited on glass slides by chemical bath deposition (CBD) method. The effects of preparative parameters such as deposition time, bath temperature, concentration of precursors, multi-layer deposition, different source of manganese, different complexing agent and thermal annealing on structural and morphological film properties have been investigated. The prepared thin films have been characterized using the X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). It exhibit the metastable forms of MnS, the hexagonal γ-MnS wurtzite phase with preferential orientation in the (002) plane or the cubic β-MnS zinc blende with preferential orientation in the (200) plane. Microstructural studies revealed the formation of MnS crystals with different morphologies, such as hexagons, spheres, cubes or flowers like.

  20. Designing Agent Utilities for Coordinated, Scalable and Robust Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Tumer, Kagan

    2005-01-01

    Coordinating the behavior of a large number of agents to achieve a system level goal poses unique design challenges. In particular, problems of scaling (number of agents in the thousands to tens of thousands), observability (agents have limited sensing capabilities), and robustness (the agents are unreliable) make it impossible to simply apply methods developed for small multi-agent systems composed of reliable agents. To address these problems, we present an approach based on deriving agent goals that are aligned with the overall system goal, and can be computed using information readily available to the agents. Then, each agent uses a simple reinforcement learning algorithm to pursue its own goals. Because of the way in which those goals are derived, there is no need to use difficult to scale external mechanisms to force collaboration or coordination among the agents, or to ensure that agents actively attempt to appropriate the tasks of agents that suffered failures. To present these results in a concrete setting, we focus on the problem of finding the sub-set of a set of imperfect devices that results in the best aggregate device. This is a large distributed agent coordination problem where each agent (e.g., device) needs to determine whether to be part of the aggregate device. Our results show that the approach proposed in this work provides improvements of over an order of magnitude over both traditional search methods and traditional multi-agent methods. Furthermore, the results show that even in extreme cases of agent failures (i.e., half the agents failed midway through the simulation) the system's performance degrades gracefully and still outperforms a failure-free and centralized search algorithm. The results also show that the gains increase as the size of the system (e.g., number of agents) increases. This latter result is particularly encouraging and suggests that this method is ideally suited for domains where the number of agents is currently in the

  1. Nonylphenolethoxylates as Malarial Chloroquine Resistance Reversal Agents

    PubMed Central

    Crandall, Ian; Charuk, Jeffrey; Kain, Kevin C.

    2000-01-01

    Malaria-associated morbidity and mortality are increasing because of widespread resistance to one of the safest and least expensive antimalarials, chloroquine. The availability of an inexpensive agent that is capable of reversing chloroquine resistance would have a major impact on malaria treatment worldwide. The interaction of nonylphenolethoxylates (NPEs, commercially available synthetic surfactants) with drug-resistant Plasmodium falciparum was examined to determine if NPEs inhibited the growth of the parasites and if NPEs could sensitize resistant parasites to chloroquine. NPEs inhibited the development of the parasite when present in the low- to mid-micromolar range (5 to 90 μM), indicating that they possess antimalarial activity. Further, the presence of <10 μM concentrations of NPEs caused the 50% inhibitory concentrations for chloroquine-resistant lines to drop to levels (≤12 nM) observed for sensitive lines and generally considered to be achievable with treatment courses of chloroquine. Long-chain (>30 ethoxylate units) NPEs were found to be most active in P. falciparum, which contrasts with previously observed maximal activity of short-chain (∼9 ethoxylate units) NPEs in multidrug-resistant mammalian cell lines. NPEs may be attractive chloroquine resistance reversal agents since they are inexpensive and may be selectively directed against P. falciparum without inhibiting mammalian tissue P glycoproteins. Antimalarial preparations that include these agents may prolong the effective life span of chloroquine and other antimalarials. PMID:10952591

  2. Gd-functionalised Au nanoparticles as targeted contrast agents in MRI: relaxivity enhancement by polyelectrolyte coating.

    PubMed

    Warsi, Muhammad Farooq; Adams, Ralph W; Duckett, Simon B; Chechik, Victor

    2010-01-21

    Monolayer-protected, Gd(3+)-functionalised gold nanoparticles with enhanced spin-lattice relaxivity (r(1)) were prepared; adsorption of polyelectrolytes on these materials further increased r(1) and ligand exchange with a biotin-derivatised disulfide led to a prototype avidin-targeted contrast agent.

  3. Integration of gas chromatography mass spectrometry methods for differentiating ricin preparation methods.

    PubMed

    Wunschel, David S; Melville, Angela M; Ehrhardt, Christopher J; Colburn, Heather A; Victry, Kristin D; Antolick, Kathryn C; Wahl, Jon H; Wahl, Karen L

    2012-05-07

    The investigation of crimes involving chemical or biological agents is infrequent, but presents unique analytical challenges. The protein toxin ricin is encountered more frequently than other agents and is found in the seeds of Ricinus communis, commonly known as the castor plant. Typically, the toxin is extracted from castor seeds utilizing a variety of different recipes that result in varying purity of the toxin. Moreover, these various purification steps can also leave or differentially remove a variety of exogenous and endogenous residual components with the toxin that may indicate the type and number of purification steps involved. We have applied three gas chromatography-mass spectrometry (GC-MS) based analytical methods to measure the variation in seed carbohydrates and castor oil ricinoleic acid, as well as the presence of solvents used for purification. These methods were applied to the same samples prepared using four previously identified toxin preparation methods, starting from four varieties of castor seeds. The individual data sets for seed carbohydrate profiles, ricinoleic acid, or acetone amount each provided information capable of differentiating different types of toxin preparations across seed types. However, the integration of the data sets using multivariate factor analysis provided a clear distinction of all samples based on the preparation method, independent of the seed source. In particular, the abundance of mannose, arabinose, fucose, ricinoleic acid, and acetone were shown to be important differentiating factors. These complementary tools provide a more confident determination of the method of toxin preparation than would be possible using a single analytical method.

  4. Collaborating with Autonomous Agents

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Cross, Charles D.; Fan, Henry; Hempley, Lucas E.; Motter, Mark A.; Neilan, James H.; Qualls, Garry D.; Rothhaar, Paul M.; Tran, Loc D.; Allen, B. Danette

    2015-01-01

    With the anticipated increase of small unmanned aircraft systems (sUAS) entering into the National Airspace System, it is highly likely that vehicle operators will be teaming with fleets of small autonomous vehicles. The small vehicles may consist of sUAS, which are 55 pounds or less that typically will y at altitudes 400 feet and below, and small ground vehicles typically operating in buildings or defined small campuses. Typically, the vehicle operators are not concerned with manual control of the vehicle; instead they are concerned with the overall mission. In order for this vision of high-level mission operators working with fleets of vehicles to come to fruition, many human factors related challenges must be investigated and solved. First, the interface between the human operator and the autonomous agent must be at a level that the operator needs and the agents can understand. This paper details the natural language human factors e orts that NASA Langley's Autonomy Incubator is focusing on. In particular these e orts focus on allowing the operator to interact with the system using speech and gestures rather than a mouse and keyboard. With this ability of the system to understand both speech and gestures, operators not familiar with the vehicle dynamics will be able to easily plan, initiate, and change missions using a language familiar to them rather than having to learn and converse in the vehicle's language. This will foster better teaming between the operator and the autonomous agent which will help lower workload, increase situation awareness, and improve performance of the system as a whole.

  5. Effects of sub-minimum inhibitory concentrations of antimicrobial agents on Streptococcus mutans biofilm formation.

    PubMed

    Dong, Liping; Tong, Zhongchun; Linghu, Dake; Lin, Yuan; Tao, Rui; Liu, Jun; Tian, Yu; Ni, Longxing

    2012-05-01

    Many studies have demonstrated that sub-minimum inhibitory concentrations (sub-MICs) of antimicrobial agents can inhibit bacterial biofilm formation. However, the mechanisms by which antimicrobial agents at sub-MICs inhibit biofilm formation remain unclear. At present, most studies are focused on Gram-negative bacteria; however, the effects of sub-MICs of antimicrobial agents on Gram-positive bacteria may be more complex. Streptococcus mutans is a major cariogenic bacterium. In this study, the S. mutans growth curve as well as the expression of genes related to S. mutans biofilm formation were evaluated following treatment with 0.5× MIC of chlorhexidine (CHX), tea polyphenols and sodium fluoride (NaF), which are common anticaries agents. The BioFlux system was employed to generate a biofilm under a controlled flow. Morphological changes of the S. mutans biofilm were observed and analysed using field emission scanning electron microscopy and confocal laser scanning microscopy. The results indicated that these three common anticaries agents could significantly upregulate expression of the genes related to S. mutans biofilm formation, and S. mutans exhibited a dense biofilm with an extensive extracellular matrix following treatment with sub-MICs of NaF and CHX. These findings suggest that sub-MICs of anticaries agents favour S. mutans biofilm formation, which might encourage dental caries progression. Copyright © 2012 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  6. Corneal Injury from Presurgical Chlorhexidine Skin Preparation.

    PubMed

    Bever, Gregory J; Brodie, Frank L; Hwang, David G

    2016-12-01

    Chlorhexidine skin preparation has been shown to provide highly effective antimicrobial presurgical skin cleansing. However, there is a significant risk of ocular toxicity when it is used in periocular areas. We describe 2 cases of significant corneal damage resulting from 4% chlorhexidine gluconate preoperative skin cleanser, despite the use of protective occlusive dressing over the eyes. Because of the potential for severe corneal toxicity resulting from use of chlorhexidine, alternative agents such as 10% povidone-iodine should be considered for skin preparation near periocular areas whenever possible. If chlorhexidine gluconate must be employed near periocular areas, great care must be exercised to avoid contact with the eyes, and additional protective measures (e.g., absorbent eye pads along with tightly occlusive dressings) must be used whenever possible. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Stability of extemporaneous oral ribavirin liquid preparation.

    PubMed

    Chan, John P; Tong, Henry H Y; Chow, Albert H L

    2004-01-01

    Ribavirin is an antiviral agent commonly used in Hong Kong for the treatment of severe acute respiratory syndrome. The choice of oral ribavirin therapeutic products available in the local market is currently limited to capsules. The present study investigated the chemical stability of an oral ribavirin suspension (200 mg/5mL) prepared extemporaneously from oral capsules using a sugar-free suspension formula. The suspension was subjected to stability testing at 4 deg C for up to 28 days. Employing a validated stability-indicating high-performance liquid chromatographic method, the ribavirin content of the extemporaneous preparation has been demonstrated to exhibit negligible changes throughout the storage period. No degradation product was observable in all high-peroformance liquid chromatograms, suggesting that the suspension remained chermically stable under the stated conditions.

  8. Evaluation of the effect of a home bleaching agent on surface characteristics of indirect esthetic restorative materials--part II microhardness.

    PubMed

    Torabi, Kianoosh; Rasaeipour, Sasan; Ghodsi, Safoura; Khaledi, Amir Ali Reza; Vojdani, Mahroo

    2014-07-01

    The exponential usage of esthetic restorative materials is beholden to society needs and desires. Interaction between the bleaching agents and the esthetic restorative materials is of critical importance. This in vitro study has been conducted to evaluate the effect of a home bleaching agent, carbamide peroxide (CP) 38%, on the microhardness of the fiber reinforced composite (FRC), overglazed, autoglazed, or polished porcelain specimens. For overglazed, autoglazed, polished ceramics and also FRC cylindrical specimens (n = 20 per group) were prepared. The specimens were stored in distilled water at 37°C for 48 hours prior to testing. Six samples from each group were selected randomly as negative controls which were stored in distilled water at 37°C that was changed daily. CP 38% was applied on the test specimens for 15 minutes, twice a day for 14 days. By using Knoop-microhardness tester microhardness testing for baseline, control and test specimens was conducted. Data were statistically analyzed using paired t-test, Mann-Whitney test, and Kruskal-Wallis test. Home bleaching significantly decreased the surface microhardness of all the test samples (p < 0.05), whereas the control groups did not show statistically significant changes after 2 weeks. The polished porcelain and polished composite specimens showed the most significant change in microhard-ness after bleaching process (p < 0.05). Although the type of surface preparation affects the susceptibility of the porcelain surface to the bleaching agent, no special preparation can preclude such adverse effects. The contact of home bleaching agents with esthetic restorative materials is unavoidable. Therefore protecting these restorations from bleaching agents and reglazing or at least polishing the restorations after bleaching is recommended.

  9. Evaluation of carrier agents for hyperpolarized xenon MRI

    NASA Technical Reports Server (NTRS)

    Venkatesh, A. K.; Zhao, L.; Balamore, D.; Jolesz, F. A.; Albert, M. S.

    2000-01-01

    Several biocompatible carrier agents, in which xenon is highly soluble and has a long T(1), were tested, and injected in living rats. These included saline, Intralipid suspension, perfluorocarbon emulsion and (129)Xe gas-filled liposomes. The T(1) of (129)Xe in these compounds ranged from 47 to 116 s. Vascular injection of these carrier agents was tolerated well, encouraging their use for further experiments in live animals. In vivo spectra, obtained from gas-filled liposomes and perfluorocarbon solutions, suggest that these carrier agents have potential for use in angiography and perfusion imaging. Copyright 2000 John Wiley & Sons, Ltd.

  10. Nanostructured Metal Oxides for Stoichiometric Degradation of Chemical Warfare Agents.

    PubMed

    Štengl, Václav; Henych, Jiří; Janoš, Pavel; Skoumal, Miroslav

    2016-01-01

    Metal oxides have very important applications in many areas of chemistry, physics and materials science; their properties are dependent on the method of preparation, the morphology and texture. Nanostructured metal oxides can exhibit unique characteristics unlike those of the bulk form depending on their morphology, with a high density of edges, corners and defect surfaces. In recent years, methods have been developed for the preparation of metal oxide powders with tunable control of the primary particle size as well as of a secondary particle size: the size of agglomerates of crystallites. One of the many ways to take advantage of unique properties of nanostructured oxide materials is stoichiometric degradation of chemical warfare agents (CWAs) and volatile organic compounds (VOC) pollutants on their surfaces.

  11. Cytocompatibility and Mechanical Properties of Short Phosphate Glass Fibre Reinforced Polylactic Acid (PLA) Composites: Effect of Coupling Agent Mediated Interface

    PubMed Central

    Hasan, Muhammad Sami; Ahmed, Ifty; Parsons, Andrew; Walker, Gavin; Scotchford, Colin

    2012-01-01

    In this study three chemical agents Amino-propyl-triethoxy-silane (APS), sorbitol ended PLA oligomer (SPLA) and Hexamethylene diisocyanate (HDI) were identified to be used as coupling agents to react with the phosphate glass fibre (PGF) reinforcement and the polylactic acid (PLA) polymer matrix of the composite. Composites were prepared with short chopped strand fibres (l = 20 mm, ϕ = 20 µm) in a random arrangement within PLA matrix. Improved, initial composite flexural strength (~20 MPa) was observed for APS treated fibres, which was suggested to be due to enhanced bonding between the fibres and polymer matrix. Both APS and HDI treated fibres were suggested to be covalently linked with the PLA matrix. The hydrophobicity induced by these coupling agents (HDI, APS) helped to resist hydrolysis of the interface and thus retained their mechanical properties for an extended period of time as compared to non-treated control. Approximately 70% of initial strength and 65% of initial modulus was retained by HDI treated fibre composites in contrast to the control, where only ~50% of strength and modulus was retained after 28 days of immersion in PBS at 37 °C. All coupling agent treated and control composites demonstrated good cytocompatibility which was comparable to the tissue culture polystyrene (TCP) control, supporting the use of these materials as coupling agent’s within medical implant devices. PMID:24955744

  12. Development of a Multifaceted Ovarian Cancer Therapeutic and Imaging Agent

    DTIC Science & Technology

    2011-04-01

    by 1-ethyl-3- [3-(dimethylamino) propyl ]carbodiimide (EDC) and N-hydroxysulfonosuccinimide (SNHS) at pH 5.5 for 30 min with a molar ratio of...particle-coated migratory substrate that can act as a permanent record of cellular movement. The gold chloride solution was prepared using 0.342 g... Synthesis and clinical Evaluation. Anticancer Agents Med. Chem. McLane, M.A., Joerger, T., Mahmoud, A., 2008. Disintegrins in health and disease. Front

  13. [Research on the marketing status of antimicrobial products and the use of antimicrobial agents indicated on product labels from 1991 through 2005].

    PubMed

    Nakashima, Harunobu; Miyano, Naoko; Matsunaga, Ichiro; Nakashima, Naomi; Kaniwa, Masa-aki

    2007-05-01

    To clarify the marketing status of antimicrobial products, descriptions on the labels of commercially available antimicrobial products were investigated from 1991 through 2005, and the results were analyzed using a database system on antimicrobial deodorant agents. A classification table of household antimicrobial products was prepared and revised, based on which target products were reviewed for any changes in the product type. The number of antimicrobial products markedly increased over 3 years starting from 1996, among which there were many products apparently not requiring antimicrobial processing. More recently, in the 2002 and 2004 surveys, while sales of kitchenware and daily necessities decreased, chemical products, baby articles, and articles for pets increased; this poses new problems. To clarify the use of antimicrobial agents in the target products, a 3-step (large, intermediate, small) classification table of antimicrobial agents was also prepared, based on which antimicrobial agents indicated on the product labels were checked. The rate of identifying the agents increased. However, this is because of the increase of chemical products and baby articles, both of which more frequently indicated the ingredient agents on the labels, and the decrease of kitchenware and daily necessities, which less frequently indicated them on the labels. Therefore there has been little change in the actual identification rate. The agents used are characterized by product types: quaternary ammonium salts, metal salts, and organic antimicrobials are commonly used in textiles, plastics, and chemical products, respectively. Since the use of natural organic agents has recently increased, the safety of these agents should be evaluated.

  14. Performance of cold-set binding agents in re-formed beef steaks.

    PubMed

    Lennon, A M; McDonald, K; Moon, S S; Ward, P; Kenny, T A

    2010-08-01

    Four cold-setting gel-forming binding agents were compared in preparation of re-formed steaks from strips of each of two muscles, M. triceps brachii-caput longum (TB) from the shoulder, and M. pectoralis profundus (PP) from the brisket, of steer forequarter. The binding agents, which were commercial preparations, were Activa, containing transglutaminase enzyme as active ingredient, Fibrimex, containing the blood plasma fractions fibrinogen and thrombin, Textor, containing a modified starch, and alginate, containing sodium alginate and Ca(++). Binding of the cooked steaks and of slices therefrom, was satisfactory for the first three of the above but relatively weak for the alginate agent. Colour of steaks was affected by binder, in that Activa and Textor treatments gave lighter, redder and yellower (higher L*, a*, b* values) steaks than did the other two. Overall acceptability ratings by taste panels corresponded with those for flavour in the case of TB steaks, with Activa and Fibrimex samples scoring highest (P<0.05). For the less tender PP steaks, the highest acceptability score was for the Textor samples, reflecting their scoring best for tenderness. Warner-Bratzler shear force values corresponded with tenderness ratings in that Textor samples had lowest shear values for both muscles, but the differences were not significant. The overall conclusion, considering cohesion, appearance, cooking yield and sensory quality of the products, was that the Activa binder performed best and would facilitate the production of good-quality chilled re-formed beef steaks from various low-value beef muscles, and without addition of sodium chloride if so desired. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  15. Kinetics and Mechanism of Bioactivation via S-Oxygenation of Anti-Tubercular Agent Ethionamide by Peracetic Acid.

    PubMed

    Chipiso, Kudzanai; Logan, Isabelle E; Eskew, Matthew W; Omondi, Benard; Simoyi, Reuben H

    2016-10-11

    The kinetics and mechanism of the oxidation of the important antitubercular agent, ethionamide, ETA (2-ethylthioisonicotinamide), by peracetic acid (PAA) have been studied. It is effectively a biphasic reaction with an initial rapid first phase of the reaction which is over in about 5 s and a second slower phase of the reaction which can run up to an hour. The first phase involves the addition of a single oxygen atom to ethionamide to form the S-oxide. The second phase involves further oxidation of the S-oxide to desulfurization of ETA to give 2-ethylisonicotinamide. In contrast to the stability of most organosulfur compounds, the S-oxide of ETA is relatively stable and can be isolated. In conditions of excess ETA, the stoichiometry of the reaction was strictly 1:1: CH 3 CO 3 H + Et(C 5 H 4 )C(═S)NH 2 → CH 3 CO 2 H + Et(C 5 H 4 )C(═NH)SOH. In this oxidation, it was apparent that only the sulfur center was the reactive site. Though ETA was ultimately desulfurized, only the S-oxide was stable. Electrospray ionization (ESI) spectral analysis did not detect any substantial formation of the sulfinic and sulfonic acids. This suggests that cleavage of the carbon-sulfur bond occurs at the sulfenic acid stage, resulting in the formation of an unstable sulfur species that can react further to form more stable sulfur species. In this oxidation, no sulfate formation was observed. ESI spectral analysis data showed a final sulfur species in the form of a dimeric sulfur monoxide species, H 3 S 2 O 2 . We derived a bimolecular rate constant for the formation of the S-oxide of (3.08 ± 0.72) × 10 2 M -1 s -1 . Oxidation of the S-oxide further to give 2-ethylisonicotinamide gave zero order kinetics.

  16. Effect of surface treatments on the flexural properties and adhesion of glass fiber-reinforced composite post to self-adhesive luting agent and radicular dentin.

    PubMed

    Elnaghy, Amr M; Elsaka, Shaymaa E

    2016-01-01

    This study evaluated the effect of different surface treatments on the flexural properties and adhesion of glass fiber post to self-adhesive luting agent and radicular dentin. Seventy-five single-rooted human teeth were prepared to receive a glass fiber post (Reblida). The posts were divided into five groups according to the surface treatment: Gr C (control; no treatment), Gr S (silanization for 60 s), Gr AP (airborne-particle abrasion), Gr HF (etching with 9 % hydrofluoric acid for 1 min), and Gr M10 (etching with CH2Cl2 for 10 min). Dual-cure self-adhesive luting agent (Rely X Unicem) was applied to each group for testing the adhesion using micropush-out test. Failure types were examined with stereomicroscope and surface morphology of the posts was characterized using a scanning electron microscopy (SEM). Flexural properties of posts were assessed using a three-point bending test. Data were analyzed using ANOVA and Tukey's HSD test. Statistical significance was set at the 0.05 probability level. Groups treated with M10 showed significantly higher bond strength than those obtained with other surface treatments (P < 0.05). In general, improvements in bond strength (MPa) were found in the following order: M10 > C > S > AP > HF. Most failure modes were adhesive type of failures between dentin and luting agent (48.2%). SEM analysis revealed that the fiber post surfaces were modified after surface treatments. The surface treatments did not compromise the flexural properties of fiber posts. Application of M10 to the fiber post surfaces enhanced the adhesion to self-adhesive luting agent and radicular dentin.

  17. Agent-based Modeling with MATSim for Hazards Evacuation Planning

    NASA Astrophysics Data System (ADS)

    Jones, J. M.; Ng, P.; Henry, K.; Peters, J.; Wood, N. J.

    2015-12-01

    Hazard evacuation planning requires robust modeling tools and techniques, such as least cost distance or agent-based modeling, to gain an understanding of a community's potential to reach safety before event (e.g. tsunami) arrival. Least cost distance modeling provides a static view of the evacuation landscape with an estimate of travel times to safety from each location in the hazard space. With this information, practitioners can assess a community's overall ability for timely evacuation. More information may be needed if evacuee congestion creates bottlenecks in the flow patterns. Dynamic movement patterns are best explored with agent-based models that simulate movement of and interaction between individual agents as evacuees through the hazard space, reacting to potential congestion areas along the evacuation route. The multi-agent transport simulation model MATSim is an agent-based modeling framework that can be applied to hazard evacuation planning. Developed jointly by universities in Switzerland and Germany, MATSim is open-source software written in Java and freely available for modification or enhancement. We successfully used MATSim to illustrate tsunami evacuation challenges in two island communities in California, USA, that are impacted by limited escape routes. However, working with MATSim's data preparation, simulation, and visualization modules in an integrated development environment requires a significant investment of time to develop the software expertise to link the modules and run a simulation. To facilitate our evacuation research, we packaged the MATSim modules into a single application tailored to the needs of the hazards community. By exposing the modeling parameters of interest to researchers in an intuitive user interface and hiding the software complexities, we bring agent-based modeling closer to practitioners and provide access to the powerful visual and analytic information that this modeling can provide.

  18. The effect of bleaching agents on the microhardness of dental aesthetic restorative materials.

    PubMed

    Türker, S B; Biskin, T

    2002-07-01

    This study investigated the effects of three home bleaching agents on the microhardness of various dental aesthetic restorative materials. The restorative materials were: feldspatic porcelain, microfilled composite resin and light-cured modified glass-ionomer cement and the bleaching agents Nite-White (16% carbamide peroxide), Opalescence (10% carbamide peroxide and carbapol jel) and Rembrandt (10% carbamide peroxide jel). A total of 90 restorative material samples were prepared 1 cm diameter and 6 mm thick and kept in distilled water for 24 h before commencing bleaching which was carried out for 8 h day-1 for 4 weeks. Microhardness measurements were then made using a Tukon tester. Statistically significant differences with respect to unbleached controls were found only for the feldspatic porcelain and microfilled composite resins (P <0.05) for Nite-White and Opalescence. All the bleaching agents decreased the microhardness of the porcelain and increased that of the light cured modified glass-ionomer cement. For the composite resin, whereas Nite-White increased its microhardness, the other bleaching agents decreased it. There were no significant differences between the bleaching agents for any of the restorative materials.

  19. Structural and optical properties of Ni-doped CdS thin films prepared by chemical bath deposition method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Premarani, R.; Saravanakumar, S., E-mail: sarophy84@gmail.com; Chandramohan, R.

    2015-06-24

    The structural and optical behavior of undoped Cadmiun Sulphide (CdS) and Ni-doped CdS thinfilms prepared by Chemical Bath Deposition (CBD) technique is reported. The crystallite sizes of the thinfilms have been characterized by X-ray diffraction pattern (XRD). The particle sizes increase with the increase of Ni content in the CdS thinfilms. Scanning Electron Microscope (SEM) results indicated that CdS thinfilms is made up of aggregate of spherical-like particles. The composition was estimated by Energy Dispersive Analysis of X-ray (EDX) and reported. Spectroscopic studies revealed considerable improvement in transmission and the band gap of the films changes with addition of Nimore » dopant that is associated with variation in crystallite sizes in the nano regime.« less

  20. Polysaccharide Production Benefits Dry Storage Survival of the Biocontrol Agent Pseudomonas fluorescens S11:P:12 Effective Against Several Maladies of Stored Potatoes

    USDA-ARS?s Scientific Manuscript database

    Pseudomonas fluorescens S11:P:12 (NRRL B-21133) is a biological control agent able to suppress several potato diseases and sprouting. Notably, it produces a polysaccharide during liquid cultivation; and the objective of this work was to determine the role of this material in the bio-control process...

  1. Synthesis of fluorine-18 labeled rhodamine B: A potential PET myocardial perfusion imaging agent

    PubMed Central

    Heinrich, Tobias K.; Gottumukkala, Vijay; Snay, Erin; Dunning, Patricia; Fahey, Frederic H; Treves, S. Ted; Packard, Alan B.

    2009-01-01

    There is considerable interest in developing an 18F-labeled PET myocardial perfusion agent. Rhodamine dyes share several properties with 99mTc-MIBI, the most commonly used single-photon myocardial perfusion agent, suggesting that an 18F-labeled rhodamine dye might prove useful for this application. In addition to being lipophilic cations, like 99mTc-MIBI, rhodamine dyes are known to accumulate in the myocardium and are substrates for Pgp, the protein implicated in MDR1 multidrug resistance. As the first step in determining whether 18F-labeled rhodamines might be useful as myocardial perfusion agents for PET, our objective was to develop synthetic methods for preparing the 18F-labeled compounds so that they could be evaluated in vivo. Rhodamine B was chosen as the prototype compound for development of the synthesis because the ethyl substituents on the amine moieties of rhodamine B protect them from side reactions, thus eliminating the need to include (and subsequently remove) protecting groups. The 2′-[18F]fluoroethyl ester of rhodamine B was synthesized by heating rhodamine B lactone with [18F]fluoroethyltosylate in acetonitrile at 165°C for 30 min.using [18F]fluoroethyl tosylate, which was prepared by the reaction of ethyleneglycol ditosylate with Kryptofix 2.2.2, K2CO3, and [18F]NaF in acetonitrile for 10 min. at 90°C. The product was purified by semi-preparative HPLC to produce the 2′-[18F]-fluoroethylester in >97% radiochemical purity with a specific activity of 1.3 GBq/μmol, an isolated decay corrected yield of 35%, and a total synthesis time of 90 min. PMID:19783150

  2. Nanoemulsions of cancer chemopreventive agent benzyl isothiocyanate display enhanced solubility, dissolution, and permeability.

    PubMed

    Qhattal, Hussaini Syed Sha; Wang, Shu; Salihima, Tri; Srivastava, Sanjay K; Liu, Xinli

    2011-12-14

    Benzyl isothiocyanate (BITC), a compound found in cruciferous vegetables, is an effective chemopreventive agent. The objective of this study was to develop nanoemulsion formulations for the oral delivery of BITC. Optimized oil-in-water BITC nanoemulsions were prepared by a spontaneous self-nanoemulsification method and a homogenization-sonication method. Both nanoemulsions entrapped high amounts of BITC (15-17 mg/mL), with low polydispersity and good colloidal stability. The BITC nanoemulsions showed enhanced solubility and dissolution compared to pure BITC. These formulations markedly increased the apical to basolateral transport of BITC in Caco-2 cell monolayers. The apparent permeability values were 3.6 × 10(-6) cm/s for pure BITC and (1.1-1.3) × 10(-5) cm/s for BITC nanoemulsions. The nanoemulsions were easily taken up by human cancer cells A549 and SKOV-3 and inhibited tumor growth in vitro. This work shows for the first time that BITC can be formulated into nanoemulsions and may show promise in enhancing absorption and bioavailability.

  3. Processes for preparing carbon fibers using gaseous sulfur trioxide

    DOEpatents

    Barton, Bryan E.; Lysenko, Zenon; Bernius, Mark T.; Hukkanen, Eric J.

    2016-01-05

    Disclosed herein are processes for preparing carbonized polymers, such as carbon fibers, comprising: sulfonating a polymer with a sulfonating agent that comprises SO.sub.3 gas to form a sulfonated polymer; treating the sulfonated polymer with a heated solvent, wherein the temperature of said solvent is at least 95.degree. C.; and carbonizing the resulting product by heating it to a temperature of 500-3000.degree. C.

  4. Partner switching promotes cooperation among myopic agents on a geographical plane

    NASA Astrophysics Data System (ADS)

    Li, Yixiao; Min, Yong; Zhu, Xiaodong; Cao, Jie

    2013-02-01

    We study the coupling dynamics between the evolution of cooperation and the evolution of partnership network on a geographical plane. While agents play networked prisoner’s dilemma games, they can dynamically adjust their partnerships based on local information about reputation. We incorporate geographical features into the process of the agent’s partner switching and investigate the corresponding effects. At each time step of the coevolution, a random agent can either update his strategy by imitation or adjust his partnership by switching from the lowest reputation partner to the highest reputation one among his neighbors. We differentiate two types of neighbors: geographical neighbors (i.e., the set of agents who are close to the focal agent in terms of geographical distance) and connectivity neighbors (i.e., the set of agents who are close to the focal agent in the partnership network in terms of geodesic distance). We find that switching to either geographical neighbors or connectivity neighbors enhances cooperation greatly in a wide parameter range. Cooperation can be favored in a much stricter condition when agents switch to connectivity neighbors more frequently. However, an increasing tendency of reconnecting to geographical neighbors shortens the geographical distance between a pair of partners on average. When agents consider the cost of geographical distance in adjusting the partnership, they are prone to reconnect to geographical neighbors.

  5. Facile preparation and characterization of ZnCdS nanocrystals for interfacial applications in photovoltaic devices.

    PubMed

    Duan, Chenghao; Luo, Weining; Jiu, Tonggang; Li, Jiangsheng; Wang, Yao; Lu, Fushen

    2018-02-15

    Recently, ZnCdS nanocrystals (NCs) have attracted intense attention because of their specific optical properties and electrical characteristics. In this paper, a green and facile solution method is reported for the preparation of ZnCdS nanocrystals using dimethylsulfoxide as small molecular ligands. The ZnCdS nanocrystals are used as an interface modification material in the photovoltaic devices. It is found that the modification of ZnCdS on TiO 2 surface not only suppresses the recombination loss of carriers but also reduces the series resistance of TiO 2 /active layer. Consequently, both of the short circuit current (J sc ) and the fill factor (FF) of the solar cells were significantly improved. Power conversion efficiency (PCE) of 7.75% based on TiO 2 /ZnCdS was achieved in contrast to 6.65% of the reference devices based on pure TiO 2 film in organic solar cells. Furthermore, the PCE of perovskite solar cells based on TiO 2 /ZnCdS was observed with 8.3% enhancement compared to that of pure TiO 2 -based ones. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Adaptive, Distributed Control of Constrained Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Bieniawski, Stefan; Wolpert, David H.

    2004-01-01

    Product Distribution (PO) theory was recently developed as a broad framework for analyzing and optimizing distributed systems. Here we demonstrate its use for adaptive distributed control of Multi-Agent Systems (MASS), i.e., for distributed stochastic optimization using MAS s. First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (Probability dist&&on on the joint state of the agents. When the game in question is a team game with constraints, that equilibrium optimizes the expected value of the team game utility, subject to those constraints. One common way to find that equilibrium is to have each agent run a Reinforcement Learning (E) algorithm. PD theory reveals this to be a particular type of search algorithm for minimizing the Lagrangian. Typically that algorithm i s quite inefficient. A more principled alternative is to use a variant of Newton's method to minimize the Lagrangian. Here we compare this alternative to RL-based search in three sets of computer experiments. These are the N Queen s problem and bin-packing problem from the optimization literature, and the Bar problem from the distributed RL literature. Our results confirm that the PD-theory-based approach outperforms the RL-based scheme in all three domains.

  7. An albumin-based gold nanocomposites as potential dual mode CT/MRI contrast agent

    NASA Astrophysics Data System (ADS)

    Zhao, Wenjing; Chen, Lina; Wang, Zhiming; Huang, Yuankui; Jia, Nengqin

    2018-02-01

    In pursuit of the biological detection applications, recent years have witnessed the prosperity of novel multi-modal nanoprobes. In this study, biocompatible bovine serum albumin (BSA)-coated gold nanoparticles (Au NPs) containing Gd (III) as the contrast agent for both X-ray CT and T1-weighted MR imaging is reported. Firstly, the Au NPs with BSA coating (Au@BSA) was prepared through a moderate one-pot reduction route in the presence of hydrazine hydrate as reducer. Sequentially, the BSA coating enables modification of diethylenetriaminepentaacetic acid (DTPA) as well as targeting reagent hyaluronic acid (HA), and further chelation of Gd (III) ions led to the formation of biomimetic nanoagent HA-targeted Gd-Au NPs (HA-targeted Au@BSA-Gd-DTPA). Several techniques were used to thoroughly characterize the formed HA-targeted Gd-Au NPs. As expected, the as-prepared nanoagent with mean diameter of 13.82 nm exhibits not only good colloid stablility and water dispersibility, but also satisfying low cytotoxicity and hemocompatibility in the tested concentration range. Additionally, for the CT phantoms, the obtained nanocomplex shows an improved contrast in CT scanning than that of Au@BSA as well as small molecule iodine-based CT contrast agents such as iopromide. Meanwhile, for the T1-weighted MRI images, there is a linear increase of contrast with concentration of Gd for the two cases of HA-targeted Gd-Au NPs and Magnevist. Strikingly, the nanoagent we explored displays a relatively higher r1 relaxivity than that of commercial MR contrast agents. Therefore, this newly constructed nanoagent could be used as contrast agents for synergistically enhanced X-ray CT and MR phantoms, holding promising potential for future biomedical applications.

  8. Bowel preparation for elective procedures in children: a systematic review and meta-analysis

    PubMed Central

    Karlsen, Fiona; Isaji, Sahira; Teck, Guan-Ong

    2017-01-01

    Objective Reviews have investigated preparation for colonoscopy, but not for surgery, They are also often limited to patients up to 16 years, despite many paediatric gastroenterologists caring for older patients. We carried out a systematic review investigating the optimum bowel preparation agents for all indications in children and young people. Design A Cochrane format systematic review of randomised controlled trials (RCTs). Data extraction and assessment of methodological quality were performed independently by two reviewers. Methodological quality was assessed using the Cochrane risk of bias tool. Patients Young people requiring bowel preparation for any elective procedure, as defined by the primary studies. Interventions RCTs comparing bowel preparation with placebo or other interventions. Main outcome measures Adequacy of bowel preparation, tolerability and adverse events. Results The search yielded 2124 results and 15 randomised controlled studies (n=1435)but heterogeneity limited synthesis. Meta-analysis of two studies comparing polyethylene glycol (PEG) with sodium phosphate showed no difference in the quality of bowel preparation (risk ratio (RR) 1.27(95% CI 0.66 to 2.44)). Two studies comparing sodium picosulfate/magnesium citrate with PEG found no difference in bowel preparation but significantly higher number of patients needing nasogastric tube insertion in the polyethylene glycol-electrolyte lavage solution (RR 0.04(95% CI 0.01 to 0.18), 45 of 117 in PEG group vs 2 of 121 in sodium picosulfate group). Meta-analysis of three studies (n=241) found no difference between PEG and sennasoids (RR 0.73(95% CI 0.31 to 1.71)). Conclusions The evidence base is clinically heterogeneous and methodologically at risk of bias. There is evidence that all regimens are equally effective. However, sodium picosulfate was better tolerated than PEG. Future research is needed with all agents and should seek to consider safety and tolerability as well as efficacy. PMID

  9. L-Cysteine capped CdTe-CdS core-shell quantum dots: preparation, characterization and immuno-labeling of HeLa cells.

    PubMed

    Zhang, Hongyan; Sun, Pan; Liu, Chang; Gao, Huanyu; Xu, Linru; Fang, Jin; Wang, Meng; Liu, Jinling; Xu, Shukun

    2011-01-01

    Functionalized CdTe-CdS core-shell quantum dots (QDs) were synthesized in aqueous solution via water-bathing combined hydrothermal method using L-cysteine (L-Cys) as a stabilizer. This method possesses both the advantages of water-bathing and hydrothermal methods for preparing high-quality QDs with markedly reduced synthesis time, and better stability than a lone hydrothermal method. The QDs were characterized by transmission electronic microscopy and powder X-ray diffraction and X-ray photoelectron spectroscopy. The CdTe-CdS QDs with core-shell structure showed both enhanced fluorescence and better photo stability than nude CdTe QDs. After conjugating with antibody rabbit anti-CEACAM8 (CD67), the as-prepared l-Cys capped CdTe-CdS QDs were successfully used as fluorescent probes for the direct immuno-labeling and imaging of HeLa cells. It was indicated that this kind of QD would have application potential in bio-labeling and cell imaging. Copyright © 2009 John Wiley & Sons, Ltd.

  10. Biological agents with potential for misuse: a historical perspective and defensive measures.

    PubMed

    Bhalla, Deepak K; Warheit, David B

    2004-08-15

    Biological and chemical agents capable of producing serious illness or mortality have been used in biowarfare from ancient times. Use of these agents has progressed from crude forms in early and middle ages, when snakes and infected cadavers were used as weapons in battles, to sophisticated preparations for use during and after the second World War. Cults and terrorist organizations have attempted the use of biological agents with an aim to immobilize populations or cause serious harm. The reasons for interest in these agents by individuals and organizations include relative ease of acquisition, potential for causing mass casualty or panic, modest financing requirement, availability of technology, and relative ease of delivery. The Centers for Disease Control and Prevention has classified Critical Biological Agents into three major categories. This classification was based on several criteria, which include severity of impact on human health, potential for delivery in a weapon, capacity to cause panic and special needs for development, and stockpiling of medication. Agents that could cause the greatest harm following deliberate use were placed in category A. Category B included agents capable of producing serious harm and significant mortality but of lower magnitude than category A agents. Category C included emerging pathogens that could be developed for mass dispersion in future and their potential as a major health threat. A brief description of the category A bioagents is included and the pathophysiology of two particularly prominent agents, namely anthrax and smallpox, is discussed in detail. The potential danger from biological agents and their ever increasing threat to human populations have created a need for developing technologies for their early detection, for developing treatment strategies, and for refinement of procedures to ensure survival of affected individuals so as to attain the ultimate goal of eliminating the threat from intentional use of

  11. Preparation of therapeutic dose of 177Lu-DOTA-TATE using a novel single vial freeze-dried kit: a comparison with 'in-situ' preparation at hospital radiopharmacy.

    PubMed

    Das, Tapas; Banerjee, Sharmila; Shinto, Ajit; Kamaleshwaran, K K; Sarma, H D

    2014-01-01

    Patient dose of (177)Lu-DOTA-TATE, used for providing radiotherapeutic treatment to the patients suffering from cancers of neuroendocrine origin, could be prepared at the hospital radiopharmacy either 'in-situ' or by using freezedried kits. The objective of the present work is to formulate and evaluate a single vial freeze-dried DOTA-TATE kit, which is capable of producing up to 7.4 GBq (200 mCi) dose of (177)Lu-DOTA-TATE and to compare the two methodologies presently used for the preparation of the agent. Freeze-dried DOTA-TATE kits, comprising a lyophilized mixture of DOTA-TATE, gentisic acid and ammonium acetate, were prepared and used for the formulation of patient doses of (177)Lu-DOTA-TATE. The kits were subjected to detailed radiochemical evaluation and the shelf-life of the kits was determined. The pharmacokinetic behavior of the agent was studied in normal Wistar rats. These kits were utilized for treating the patients suffering from various types of neuroendocrine cancers. The freeze-dried kits were used for the preparation of up to 7.4 GBq (200 mCi) therapeutic doses of (177)Lu- DOTA-TATE with a radiochemical purity of >99% and were found to have sufficiently long shelf-life. Biological studies carried out in normal Wistar rats exhibited no significant accumulation of activity in any of the vital organs/tissue except in kidneys and non-accumulated activity showed major renal clearance. Clinical studies carried out in cancer patients exhibited accumulation of activity in the cancerous lesions and metastatic sites. The kit was useful for the convenient preparation of therapeutic dose of (177)Lu-DOTA-TATE, suitable for human administration. The use of kit is expected to reduce the batch failure and radiation exposure to the working personnel.

  12. Investigation on the interface between Li10GeP2S12 electrolyte and carbon conductive agents in all-solid-state lithium battery.

    PubMed

    Yoon, Kyungho; Kim, Jung-Joon; Seong, Won Mo; Lee, Myeong Hwan; Kang, Kisuk

    2018-05-23

    All-solid-state batteries are considered as one of the attractive alternatives to conventional lithium-ion batteries, due to their intrinsic safe properties benefiting from the use of non-flammable solid electrolytes in ASSBs. However, one of the issues in employing the solid-state electrolyte is the sluggish ion transport kinetics arising from the chemical and physical instability of the interfaces among solid components including electrode material, electrolyte and additive agents. In this work, we investigate the stability of the interface between carbon conductive agents and Li 10 GeP 2 S 12 in a composite cathode and its effect on the electrochemical performance of ASSBs. It is found that the inclusion of various carbon conductive agents in composite cathode leads to inferior kinetic performance of the cathode despite expectedly enhanced electrical conductivity of the composite. We observe that the poor kinetic performance is attributed to a large interfacial impedance which is gradually developed upon the inclusions of the various carbon conductive agents regardless of their physical differences. The analysis through X-ray Photoelectron Spectroscopy suggests that the carbon additives in the composite cathode stimulate the electrochemical decomposition of LGPS electrolyte degrading its surface during cycling, indicating the large interfacial resistance stems from the undesirable decomposition of the electrolyte at the interface.

  13. Effects of Contamination by Hemostatic Agents and Use of Cleaning Agent on Etch-and-Rinse Dentin Bond Strength.

    PubMed

    Pucci, César Rogério; Araújo, Rodrigo Maximo de; Lacerda, Ana Julia Farias de; Souza, Mirella Anjos de; Huhtala, Maria Filomena Rocha Lima; Feitosa, Fernanda Alves

    2016-01-01

    The aim of this study was to evaluate the influence of contamination by hemostatic agents and rinsing with chlorhexidine on bond strength between dentin and resin composite. Ninety-six bovine teeth were sectioned to expose a flat dentin surface area. A standardized cavity with 2.0 mm in thickness, superficial diameter of 4.0 mm and bottom diameter of 3.0 mm was prepared with a diamond bur in each dentin specimen. The teeth were divided into four groups according to the hemostatic employed: G1: control; G2: use of ViscoStat, Ultradent; G3: Hemosthasegel, FGM; and G4: Hemostop, Dentsply. The groups were divided into two subgroups according to the cleaning protocol method (n=12): A: without any further cleaning; and B: cleaning with chlorhexidine at 0.2%. All cavities were filled using a dentin adhesive and a resin composite, following the manufacturer's instructions. After 24 h, the specimens were aged by thermal and mechanical cycling. The bond strength was determined by the push out bond test (MPa), Statistical analysis was performed using two-way ANOVA and Tukey test (p<0.05). Statistically significant differences were detected among all groups treated with hemostatic agents and the control group. The post-hoc test showed that cleaning the cavity with chlorhexidine significantly improves the bond strength between dentin and resin composite. Our results suggested that the use of chlorhexidine can reestablish the bond strength between dentin and resin composite when a hemostatic agent was applied.

  14. Preparation of antimicrobial fabric using magnesium-based PET masterbatch

    NASA Astrophysics Data System (ADS)

    Zhu, Yimin; Wang, Ying; Sha, Lin; Zhao, Jiao

    2017-12-01

    The magnesium-based antimicrobial polyethylene terephthalate (PET) masterbatch (MAPM) was extruded from twin screw extruder by melting-and-mixing method, using magnesium-based antimicrobial agent (MAA) as the functional material for the first time. The magnesium-based antimicrobial fabric (MAPF) was prepared using MAPM and pure PET resin by high-speed melt-spinning technology and weaving technology for the first time. The materials used in this work were healthy to human body and friendly to environment. The characteristics of MAA, MAPM and MAPF were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). When the MAPM (MAA) content reached to 25 wt.% (5 wt.%) in MAPF, the MAA had excellent dispersion and compatibility in MAPF, and the MAPF had good physico-mechanical properties. Then the MAPF presented excellent spinnability and antimicrobial property against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Candida albicans (C. albicans) and Aspergillus niger (A. niger), with pretty good laundering durability.

  15. A virally inactivated functional growth factor preparation from human platelet concentrates.

    PubMed

    Su, C-Y; Kuo, Y P; Lin, Y C; Huang, C-T; Tseng, Y H; Burnouf, T

    2009-08-01

    Human platelet growth factors (HPGF) are essential for tissue regeneration and may replace fetal bovine serum (FBS) in cell therapy. No method for the manufacture of standardized virally inactivated HPGF has been developed yet. Platelet concentrates (PC) were subjected to solvent/detergent (S/D) treatment (1% TnBP/1% Triton X-45), oil extraction, hydrophobic interaction chromatography and sterile filtration. Platelet-derived growth factor (PDGF)-AB, -BB and -AA, transforming growth factor-beta1 (TGF-beta1), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1) and vascular endothelium growth factor (VEGF) were measured by ELISA. Composition in proteins and lipids was determined, protein profiles were obtained by SDS-PAGE, and TnBP and Triton X-45 were assessed by gas chromatography and high-performance liquid chromatography, respectively. Cell growth promoting activity of HPGF was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay using human embryonic kidney (HEK293A) fibroblast and Statens Seruminstitute rabbit corneal (SIRC) epithelial cell lines. The GF preparation contained a mean of 16.66, 2.04, 1.53, 72.19, 0.33, 48.59 and 0.44 ng/ml of PDGF-AB, -BB, -AA, TGF-beta1, EGF, IGF-1 and VEGF, respectively. The protein profile was typical of platelet releasates and had less than 2 p.p.m. of residual S/D agents. MTS assay of HEK293A and SIRC cultures showed that the GF preparation at 10% and 0.1% (v/v), respectively, could successfully replace 10% FBS for cell proliferation. Cell-stimulating activity of HPGF on HEK293A was over twice that of PC releasates. STANDARDIZED and functional virally inactivated HPGF can be prepared from human PC for possible applications in cell therapy and regenerative medicine.

  16. Well-defined single polymer nanoparticles for the antibody-targeted delivery of chemotherapeutic agents.

    PubMed

    Lane, D D; Chiu, D Y; Su, F Y; Srinivasan, S; Kern, H B; Press, O W; Stayton, P S; Convertine, A J

    2015-02-28

    Aqueous reversible addition-fragmentation chain transfer (RAFT) polymerization was employed to prepare a series of linear copolymers of N,N-dimethylacrylamide (DMA) and 2-hydroxyethylacrylamide (HEAm) with narrow Đ values over a molecular weight range spanning three orders of magnitude (10 3 to 10 6 Da). Trithiocarbonate-based RAFT chain transfer agents (CTAs) were grafted onto these scaffolds using carbodiimide chemistry catalyzed with DMAP. The resultant graft chain transfer agent (gCTA) was subsequently employed to synthesize polymeric brushes with a number of important vinyl monomer classes including acrylamido, methacrylamido, and methacrylate. Brush polymerization kinetics were evaluated for the aqueous RAFT polymerization of DMA from a 10 arm gCTA. Polymeric brushes containing hydroxyl functionality were further functionalized in order to prepare 2nd generation gCTAs which were subsequently employed to prepare polymers with a brushed-brush architecture with molecular weights in excess of 10 6 Da. These resultant single particle nanoparticles (SNPs) were employed as drug delivery vehicles for the anthracycline-based drug doxorubicin via copolymerization of DMA with a protected carbazate monomer (bocSMA). Cell-specific targeting functionality was also introduced via copolymerization with a biotin-functional monomer (bioHEMA). Drug release of the hydrazone linked doxorubicin was evaluated as function of pH and serum and chemotherapeutic activity was evaluated in SKOV3 ovarian cancer cells.

  17. 39 CFR 2.2 - Agent for receipt of process.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 39 Postal Service 1 2013-07-01 2013-07-01 false Agent for receipt of process. 2.2 Section 2.2 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE GENERAL AND TECHNICAL PROVISIONS (ARTICLE II) § 2.2 Agent for receipt of process. The General Counsel of the Postal...

  18. 39 CFR 2.2 - Agent for receipt of process.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Agent for receipt of process. 2.2 Section 2.2 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE GENERAL AND TECHNICAL PROVISIONS (ARTICLE II) § 2.2 Agent for receipt of process. The General Counsel of the Postal...

  19. 39 CFR 2.2 - Agent for receipt of process.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Agent for receipt of process. 2.2 Section 2.2 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE GENERAL AND TECHNICAL PROVISIONS (ARTICLE II) § 2.2 Agent for receipt of process. The General Counsel of the Postal...

  20. 39 CFR 2.2 - Agent for receipt of process.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Agent for receipt of process. 2.2 Section 2.2 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE GENERAL AND TECHNICAL PROVISIONS (ARTICLE II) § 2.2 Agent for receipt of process. The General Counsel of the Postal...