keyword
MENU ▼
Read by QxMD icon Read
search

UV

keyword
https://www.readbyqxmd.com/read/28645148/a-soft-environmental-control-effect-of-apatite-doped-with-mineral-traces-in-the-fowl-droppings
#1
M Minamisawa, T Taniai, S Yoshida
Fowl-dropping apatite (Ca10-z[PO4]6-z[OH]2-z) synthesized from carbonized, incinerated fowl droppings contains PO4 and OH groups that are partially substituted by CO32- ions. It shows stronger ion conductivity than commercially available hydroxyapatite in a wide range of temperatures from 23°C to 800°C. Fowl-dropping apatite readily adsorbs NO2 and SO2 gases and, without re-releasing these gases, slowly decomposes them at room temperature under sunlight via ultraviolet-visible (UV-Vis) irradiation. A limited amount of minerals and organics contained in fowl droppings causes light-induced activities in fowl-dropping apatite with a crystal structure that has a developed c face; this initiates excitation-induced atomic transfer on the solid surface derived from PO4 exposed on the c face, which then advances the decomposition reaction...
June 21, 2017: Poultry Science
https://www.readbyqxmd.com/read/28644908/photoactive-surface-grafted-polymer-brushes-with-phthalocyanine-bridging-groups-as-an-advanced-architecture-for-light-harvesting
#2
Michał Szuwarzyński, Karol Wolski, Agata Pomorska, Tomasz Uchacz, Arkadiusz Gut, Łukasz Łapok, Szczepan Zapotoczny
Surface-grafted polymer brushes of novel ladder-like architecture were proposed for inducing ordering of chromophores embedded therein. The brushes with acetylene side groups were obtained by surface-initiated photoiniferter-mediated polymerization. The acetylene moieties reacted then via "click" process with an axially azide-bifunctionalized silicon phthalocyanine bridging the neighboring chains that inherently adopt extended conformations in dense brushes. FTIR, quartz crystal microbalance, atomic force microscopy were used to study formation and structure of the photoactive brushes varying in grafting densities...
June 23, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28644644/highly-nuclear-spin-polarized-deuterium-atoms-from-the-uv-photodissociation-of-deuterium-iodide
#3
Dimitris Sofikitis, Pavle Glodic, Greta Koumarianou, Hongyan Jiang, Lykourgos Bougas, Peter C Samartzis, Alexander Andreev, T Peter Rakitzis
We report a novel highly spin-polarized deuterium (SPD) source, via the photodissociation of deuterium iodide at 270 nm. I(^{2}P_{3/2}) photofragments are ionized with m-state selectivity, and their velocity distribution measured via velocity-map slice imaging, from which the D polarization is determined. The process produces ∼100% electronically polarized D at the time of dissociation, which is then converted to ∼60% nuclear D polarization after ∼1.6  ns. These production times for SPD allow collision-limited densities of ∼10^{18}  cm^{-3} and at production rates of ∼10^{21}  s^{-1} which are 10^{6} and 10^{4} times higher than conventional (Stern-Gerlach separation) methods, respectively...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28644630/expanding-the-therapeutic-potential-of-the-iron-chelator-deferasirox-in-the-development-of-aqueous-stable-ti-iv-anticancer-complexes
#4
Sergio A Loza-Rosas, Alexandra M Vázquez-Salgado, Kennett I Rivero, Lenny J Negrón, Yamixa Delgado, Josué A Benjamín-Rivera, Angel L Vázquez-Maldonado, Timothy B Parks, Charlene Munet-Colón, Arthur D Tinoco
The recent X-ray structure of titanium(IV)-bound human serum transferrin (STf) exhibiting citrate as a synergistic anion reveals a difference in Ti(IV) coordination versus iron(III), the metal endogenously delivered by the protein to cells. This finding enriches our bioinspired drug design strategy for Ti(IV)-based anticancer therapeutics, which applies a family of Fe(III) chelators termed chemical transferrin mimetic (cTfm) ligands to inhibit Fe bioavailability in cancer cells. Deferasirox, a drug used for iron overload disease, is a cTfm ligand that models STf coordination to Fe(III), favoring Fe(III) binding versus Ti(IV)...
June 23, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28644611/transient-fiber-mats-of-electrospun-poly-propylene-carbonate-composites-with-remarkable-mechanical-strength
#5
Peter Ohlendorf, Alexander Ruyack, Amanda K Leonardi, Chengjian Shi, Christine Cuppoletti, Ian Bruce, Amit Lal, Christopher K Ober
Polymers with a triggered decomposition are attractive for an array of applications ranging from patterning to transient packaging materials as well as for environmental protection. This work showed for the first time UV and thermally triggered transience in fiber mats using poly(propylene carbonate) (PPC) composites. The electrospun PPC-composite fiber mats combine excellent decomposition performance (due to the high surface to volume ratio) with high stiffness and thus represent a new class of materials enabling innovative applications such as transient filter materials, short-time plant protection materials as well as temporary lightweight materials for aerospace engineering...
June 23, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28644503/the-first-re-i-organometallic-complex-with-an-organoimido-polyoxometalate-ligand
#6
Patricio Hermosilla-Ibáñez, Kerry Wrighton-Araneda, Gaspar Prado, Verónica Paredes-García, Nancy Pizarro, Andrés Vega, Diego Venegas-Yazigi
The spectroscopic, electrochemical and photophysical properties of the first Re(I) organometallic organoimido-polyoxometalate complex [n-Bu4N][Mo6O18NC6H4-CH2-N3C2H2-Re-phen(CO)3] compared with all fragments are reported. The UV-Vis spectra are analysed using experimental and theoretical tools. In contrast to the reported studies in the literature, our results show that a new more intense band is present in the spectra of the hybrid ligand obscuring the intra-polyanion charge transfer. The electrochemical results show that the strong acceptor character of the polyoxometalate fragment is quenched by the condensation of the phenyl-triazole molecule...
June 23, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28644497/novel-tunable-green-red-emitting-oxynitride-phosphors-co-activated-with-ce-3-tb-3-and-eu-3-photoluminescence-and-energy-transfer
#7
Jiansheng Huo, Langping Dong, Wei Lü, Baiqi Shao, Hongpeng You
A series of novel Ce(3+), Tb(3+) and Eu(3+) ion doped Y4SiAlO8N-based oxynitride phosphors were synthesized by the solid-state method and characterized by X-ray powder diffraction, scanning electron microscopy, photoluminescence, lifetimes and thermo-luminescence. The excitation of the Ce(3+)/Tb(3+) co-doped and Ce(3+)/Tb(3+)/Eu(3+) tri-doped phosphor with near-UV radiation results in strong linear Tb(3+) green and Eu(3+) red emission. The occurrence of Ce(3+)-Tb(3+) and Ce(3+)-Tb(3+)-Eu(3+) energy transfer processes is responsible for the bright green or red luminescence...
June 23, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28644466/characterization-of-a-selenocysteine-ligated-p450-compound-i-reveals-direct-link-between-electron-donation-and-reactivity
#8
Elizabeth L Onderko, Alexey Silakov, Timothy H Yosca, Michael T Green
Strong electron-donation from the axial thiolate ligand of cytochrome P450 has been proposed to increase the reactivity of compound I with respect to C-H bond activation. However, it has proven difficult to test this hypothesis, and a direct link between reactivity and electron donation has yet to be established. To make this connection, we have prepared a selenolate-ligated cytochrome P450 compound I intermediate. This isoelectronic perturbation allows for direct comparisons with the wild-type enzyme. Selenium incorporation was achieved using a cysteine auxotrophic Escherichia coli strain...
July 2017: Nature Chemistry
https://www.readbyqxmd.com/read/28644401/the-investigation-of-electrochemistry-behaviors-of-tyrosinase-based-on-directly-electrodeposited-grapheneon-choline-gold-nanoparticles
#9
Yaping He, Xiaohui Yang, Quan Han, Jianbin Zheng
A novel catechol (CA) biosensor was developed by embedding tyrosinase (Tyr) onto in situ electrochemical reduction graphene (EGR) on choline-functionalized gold nanoparticle (AuNPs-Ch) film. The results of UV-Vis spectra indicated that Tyr retained its original structure in the film, and an electrochemical investigation of the biosensor showed a pair of well-defined, quasi-reversible redox peaks with Epa = -0.0744 V and Epc = -0.114 V (vs. SCE) in 0.1 M, pH 7.0 sodium phosphate-buffered saline at a scan rate of 100 mV/s...
June 23, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28644383/use-of-ultrasonication-technology-for-the-increased-production-of-plant-secondary-metabolites
#10
REVIEW
Md Mohidul Hasan, Tufail Bashir, Hanhong Bae
Plant secondary metabolites (PSMs) provide taste, color, odor, and resistance to plants, and they are also used to treat cancer and cardiovascular diseases. Synthesis of PSMs in plants is stimulated in response to different forms of external stress. Use of ultrasonication (US) to clean or decontaminate fruits and vegetables leads to physical stress that finally results in the accumulation of PSMs. US can stimulate accumulation of taxol, ginsenoside saponins, shikonin, and resveratrol, e.g., up to 319-fold increase of resveratrol synthesis has been observed in grape due to US...
June 23, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28643895/light-switchable-azobenzene-containing-macromolecules-from-uv-to-near-infrared
#11
REVIEW
Philipp Weis, Si Wu
Azobenzene-containing macromolecules (azo-macromolecules) such as azobenzene-containing polymers (azopolymers) and azobenzene-functionalized biomacromolecules are photoswitchable macromolecules. Trans-to-cis photoisomerization in conventional azo-macromolecules is induced by ultraviolet (UV) light. However, UV light cannot penetrate deeply into issue and has a very small fraction in sunlight. Therefore, conventional azo-macromolecules are problematic for biomedical and solar-energy-related applications. In this Feature Article, the strategies for constructing visible and near-infrared (NIR) light-responsive azo-macromolecules are reviewed, and the potential applications of visible- and NIR-light-responsive azo-macromolecules in biomedicine and solar energy conversion are highlighted...
June 23, 2017: Macromolecular Rapid Communications
https://www.readbyqxmd.com/read/28643838/organics-filled-one-dimensional-tio2-nanowires-array-ultraviolet-detector-with-enhanced-photo-conductivity-and-dark-resistivity
#12
Dezhong Zhang, Chunyu Liu, Bo Yin, Ruiliang Xu, Jingran Zhou, Xindong Zhang, Shengping Ruan
A heterojunction photo-conductive ultraviolet (UV) detector was developed based on TiO2 nanowires array (NWA) surrounded by N,N'-bis-(1-naphthalenyl)-N,N'-bis-phenyl-(1,1'-biphenyl)-4,4'-diamine (NPB). The novel and effective two-step method of static infusion and dynamic solution-cleaning was employed to fill NPB into TiO2 NWA gaps and simultaneously remove the unwelcomed top NPB layer. The device fabricated via the two-step method exhibited optimal performance compared to TiO2/NPB device with top NPB layer and TiO2 NWA device...
June 23, 2017: Nanoscale
https://www.readbyqxmd.com/read/28643834/understanding-the-remarkable-luminescence-enhancement-via-sio2-coating-on-tio2-eu-3-nanofibers
#13
Meiqi Chang, Yanhua Song, Ye Sheng, Jie Chen, Haifeng Zou
TiO2:Eu(3+) nanofibers diameters can be tuned by changing the mixed solvent ratio are synthesized via the electrospinning technique. Concentration quenching phenomena and the relationship of the PL intensity ratio I((5)D0-(7)F2)/I((5)D0-(7)F1) with the Eu doping concentration are discussed. Notably, the luminescence intensity is enhanced by about 7.8 fold by coating SiO2 gel layer on the TiO2:Eu(3+) nanofibers, which is successfully performed via a sol-gel process followed by calcination. Furthermore, these fibers are characterized systematically via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), Fourier transform infrared spectroscopy (FT-IR), and photoluminescence (PL) spectroscopy...
June 23, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28643284/hydroxyl-radical-mediated-degradation-of-diclofenac-revisited-a-computational-approach-to-assessment-of-reaction-mechanisms-and-by-products
#14
Sesil Agopcan Cinar, Asu Ziylan-Yavaş, Saron Catak, Nilsun H Ince, Viktorya Aviyente
Advanced oxidation processes (AOPs) are based on the in situ production of hydroxyl radicals (•OH) and reactive oxygen species (ROS) in water upon irradiation of the sample by UV light, ultrasound, electromagnetic radiation, and/or the addition of ozone or a semiconductor. Diclofenac (DCF), one of the emerging organic contaminants (EOC), is of environmental concern due to its abundancy in water and is known to be subjected to AOPs. The current study uses density functional theory (DFT) to elucidate the mechanisms of the reactions between •OH and DCF leading to degradation by-products, P1-P9...
June 23, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28643281/removal-of-the-emerging-contaminant-bisphenol-a-by-an-ureasil-peo-hybrid-membrane-experimental-study-and-molecular-dynamic-simulation
#15
Lilian K de Oliveira, André L A Moura, Valdir Barbosa, Renato L T Parreira, Rodrigo S Banegas, Giovanni F Caramori, Katia J Ciuffi, Eduardo F Molina
This work reports the use of a cross-linked ureasil-PEO hybrid matrix (designated PEO800) as an efficient adsorbent to retain the emerging contaminant bisphenol A (BPA) from an aqueous medium. The in-deep experimental and theoretical results provide information about the interactions between PEO800 and BPA. The in situ UV-vis spectroscopy data and the pseudo-first order, pseudo-second order, Elovich, and Morris-Webber intraparticle diffusion models allowed us to propose a three-step mechanism for the adsorption of BPA onto PEO800...
June 22, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28643099/-beyond-antibiotic-therapy-future-antiinfective-strategies-update-2017
#16
REVIEW
D Vogt, S Sperling, T Tkhilaishvili, A Trampuz, J-P Pirnay, C Willy
BACKGROUND: The key elements in the therapy of surgical site infections (SSI) are surgical debridement and local and systemic antibiotic therapy; however, due to increasing antibiotic resistance, the development of additional therapeutic measures is of great interest for future trauma and orthopedic surgery. METHOD: Against the background of our own experimental and clinical experiences and on the basis of the current literature, possible future anti-infective strategies were elaborated...
June 22, 2017: Der Unfallchirurg
https://www.readbyqxmd.com/read/28642952/solventless-mechanochemical-preparation-of-novel-magnetic-bioconjugates
#17
Daily Rodriguez-Padrón, Alain R Puente-Santiago, Alina M Balu, Antonio A Romero, Rafael Luque
A solventless mechanochemical approach was employed to obtain a bioconjugate (BSA-DA-Fe2O3) based on bovine serum albumin (BSA) and dopamine (DA) coated iron oxide magnetic nanoparticles. UV-vis measurements of the obtained material showed a distinctive peak at 280 nm which, together with the presence of N on the surface of the nanomaterial (a band at 400 eV in the XPS spectrum) and zeta potential measurements, confirmed the successful immobilization of the protein. Additionally, the presence of two bands at 1652 and 1545 cm(-1) in the FT-IR spectra of both BSA and BSA-DA-Fe2O3 and steady-state fluorescence analysis validated that the protein preserved its native-like structure after the mechanochemical milling process...
June 23, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28642944/magnetic-circular-dichroism-of-ucl6-in-the-ligand-to-metal-charge-transfer-spectral-region
#18
Frédéric Gendron, Valerie E Fleischauer, Thomas J Duignan, Brian L Scott, Matthias W Löble, Samantha K Cary, Stosh A Kozimor, Hélène Bolvin, Michael L Neidig, Jochen Autschbach
We present a combined ab initio theoretical and experimental study of the magnetic circular dichroism (MCD) spectrum of the octahedral UCl6(-) complex ion in the UV-Vis spectral region. The ground state is an orbitally non-degenerate doublet E5/2u and the MCD is a -term spectrum caused by spin-orbit coupling. Calculations of the electronic spectrum at various levels of theory indicate that differential dynamic electron correlation has a strong influence on the energies of the dipole-allowed transitions and the envelope of the MCD spectrum...
June 23, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28642919/correlation-between-antioxidant-activity-and-bonding-strength-on-bleached-enamel
#19
Hellen Caroliny De Carvalho, Ricardo Danil Guiraldo, Regina Célia Poli-Frederico, Sandra Mara Maciel, Sandra Kiss Moura, Murilo Baena Lopes, Sandrine Bittencourt Berger
Objective: This study used the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) method to evaluate the percentage of antioxidant activity (%AA) of green tea (GT) and sodium ascorbate (SA) gel in three concentrations (10%, 20% and 30%), and the influence of these concentrations on the microshear bond strength (μ-SBT) values of bleached enamel, using 10% carbamide peroxide (CP). Materials and methods: Eighty intact third molars were selected to perform the μ-SBT test, and were randomly divided into eight experimental groups: G1: positive control - no treatment; G2: negative control - bleached with CP; G3: PC +10% GT; G4: PC +20% GT; G5: PC +30% GT; G6: PC +10% SA; G7: PC +20% SA and G8: PC +30% SA...
December 2016: Acta Biomaterialia Odontologica Scandinavica
https://www.readbyqxmd.com/read/28642787/mutational-signatures-are-critical-for-proper-estimation-of-purifying-selection-pressures-in-cancer-somatic-mutation-data-when-using-the-dn-ds-metric
#20
Jimmy Van den Eynden, Erik Larsson
Large cancer genome sequencing initiatives have led to the identification of cancer driver genes based on signals of positive selection in somatic mutation data. Additionally, the identification of purifying (negative) selection has the potential to identify essential genes that may be of therapeutic interest. The most widely used way of quantifying selection pressures in protein-coding genes is the dN/dS metric, which compares non-synonymous to synonymous substitution rates. In this study, we examine whether and how this metric is influenced by the mutational processes that have been active during tumor evolution...
2017: Frontiers in Genetics
keyword
keyword
56252
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"