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https://www.readbyqxmd.com/read/28432968/applicability-of-light-sources-and-the-inner-filter-effect-in-uv-acetylacetone-and-uv-h2o2-processes
#1
Bingdang Wu, Minghui Yang, Ran Yin, Shujuan Zhang
Light source is a crucial factor in the application of a photochemical process, which determines the energy efficiency. The performances of acetylacetone (AA) in conversion of aqueous contaminants under irradiation with a low-pressure mercury lamp, a medium-pressure mercury lamp, a xenon lamp, and natural sunlight were investigated and compared with those of H2O2 as reference. In all cases, AA was superior to H2O2 in the degradation of Acid Orange 7. Using combinations of the different light sources with various cut-off and band-pass filters, the spectra responses of the absorbed photons in the UV/AA and UV/H2O2 processes were determined for two colored and two colorless compounds...
April 10, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28422180/patterning-graphene-film-by-magnetic-assisted-uv-ozonation
#2
Yixuan Wu, Haihua Tao, Shubin Su, Huan Yue, Hao Li, Ziyu Zhang, Zhenhua Ni, Xianfeng Chen
Developing an alternative method for fabricating microscale graphene patterns that overcomes the obstacles of organic contamination, linewidth resolution, and substrate damaging is paramount for applications in optoelectronics. Here we propose to pattern chemical vapor deposition grown graphene film through a stencil mask by magnetic-assisted ultraviolet (UV) ozonation under irradiation of a xenon excimer lamp. In this process, the paramagnetic oxygen molecules and photochemically generated oxygen radicals are magnetized and attracted in an inhomogenous external magnetic field...
April 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28413526/neuroendoscopy-is-it-safe
#3
Manas Panigrahi, Bharat Gupta, Rajesh Reddy
BACKGROUND: The effect of heat in endoscopic instruments used for laparoscopy and hysteroscopy has been well-studied. Reports of thermal injury from nasal endoscopes have also been reported. However, there are no experimental studies, which have objectively documented and provided recommendations for safe use of endoscopes in neurosurgery. OBJECTIVES: To study the heat generated at the tip of the endoscope and the subsequent thermal damage caused to a cotton drape placed in proximity, by varying the intensity of light delivered through different optical cables, ambient (operating room) temperatures and working distances...
January 2017: Asian Journal of Neurosurgery
https://www.readbyqxmd.com/read/28409925/conformational-changes-in-5-methoxyindole-effects-of-thermal-vibrational-and-electronic-excitations
#4
António Jorge Lopes Jesus, Rui Fausto, Igor Reva
The molecule of 5-methoxyindole (5MOI) may adopt two conformational states, syn and anti, with respect to the relative orientation of the NH and OCH3 groups. Structure of monomeric 5MOI was characterized spectroscopically, in mid- and near-infrared domains. The conformational composition of 5MOI could be controlled in three different ways. Thermally, two conformers of 5MOI could be trapped in xenon matrixes at 16 K. Upon annealing the xenon matrix to temperatures about 30-40 K, the higher energy syn form converted to the ground state anti conformer...
April 14, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28402289/a-gas-scintillator-detector-for-2d-dose-profile-monitoring-in-pencil-beam-scanning-and-pulsed-beam-proton-radiotherapy-treatments
#5
Steven E Vigdor, Alexander Klyachko, Keith Solberg, Mark Pankuch
In order to address dosimetry demands during proton therapy treatments utilizing pencil beam scanning and/or pulsed beam accelerators, we have developed a xenon-filled Gas Scintillation Detector (GSD) that can monitor delivered dose and two-dimensional beam centroid position pulse-by-pulse in real time, with high response linearity up to high instantaneous dose rates. We present design considerations for the GSD and results of beam tests carried out at operating proton therapy clinics. In addition to demonstrating spatial resolution with σ of a few hundred microns in each transverse dimension and relative dose precision better than 1% over large treatment areas, the test beam results also reveal the dependence of the GSD dose normalization on dose rate, beam energy, and gas impurities...
April 12, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28400024/impact-of-a-combined-processing-technology-involving-ultrasound-and-pulsed-light-on-structural-and-physiological-changes-of-saccharomyces-cerevisiae-ke-162-in-apple-juice
#6
Mariana Ferrario, Sandra Guerrero
This study analyzed the effect of single ultrasound (US) (600 W, 20 kHz and 95.2 μm wave amplitude, 10 or 30 min at 20 or 44 ± 1 °C), or combined with pulsed light technology (PL) with controlled heat build-up (Xenon lamp, 3 pulses/s, 71.6 J/cm(2), temperature ranges: 2-20 ± 1 °C and 44-56 ± 1 °C) on the inactivation of Saccharomyces cerevisiae KE 162 cells in commercial (pH: 3.5 ± 0.1; 12.5 ± 0.1 °Brix) and freshly pressed (pH: 3.4 ± 0.1; 12.6 ± 0.1 °Brix) apple juices...
August 2017: Food Microbiology
https://www.readbyqxmd.com/read/28398653/the-noble-gas-xenon-provides-protection-and-trophic-stimulation-to-midbrain-dopamine-neurons
#7
Jérémie Lavaur, Déborah Le Nogue, Marc Lemaire, Jan Pype, Géraldine Farjot, Etienne C Hirsch, Patrick P Michel
Despite its low chemical reactivity, the noble gas xenon possesses a remarkable spectrum of biological effects. In particular, xenon is a strong neuroprotectant in preclinical models of hypoxic-ischemic brain injury. In the present study, we wished to determine whether xenon retained its neuroprotective potential in experimental settings that model the progressive loss of midbrain dopamine (DA) neurons in Parkinson's disease (PD). Using rat midbrain cultures, we established that xenon was partially protective for DA neurons through either direct or indirect effects on these neurons...
April 11, 2017: Journal of Neurochemistry
https://www.readbyqxmd.com/read/28394036/role-of-the-methoxy-groups-in-cryptophanes-for-complexation-of-xenon-conformational-selection-evidenced-by-129xe-1h-nmr-spinoe-experiments
#8
Thierry Brotin, Patrick Berthault, Céline Boutin, Erwann Jeanneau, Estelle Léonce
We report the laser-polarized 129Xe and 1H NMR spectra of a series of cryptophane derivatives that differ only by the number of methoxy groups attached on their benzene rings and the arrangement syn or anti of the linkers (compounds 6a-s, 9a-s, 12a-s). All these compounds bind xenon even though the characteristic signal of the gas encapsulated in the cavity of the cage-molecule cannot be always detected. Interestingly, the exchange dynamics of xenon strongly depends on the degree of substitution and is different from that of the cryptophane derivatives studied previously...
April 10, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28391073/structural-optical-and-photoluminescence-properties-of-eu-3-doped-zno-nanoparticles
#9
Odireleng Martin Ntwaeaborwa, Sefako J Mofokeng, Vinod Kumar, Robin E Kroon
The structure, particle morphology and luminescent properties of europium (Eu(3+)) doped ZnO nanoparticles (NPs) prepared by co-precipitation method are discussed. When excited using a 325nm He-Cd laser, undoped ZnO NPs exhibited weakly the well-known ultraviolet excitonic recombination emission (at ~384nm) and strongly broad band visible emissions associated with defects (at ~600nm). In addition, the ZnO NPs exhibited green emission at ~600nm associated with defects when excited using a monochromatized xenon lamp...
April 1, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28384123/magnetic-resonance-imaging-with-hyperpolarized-agents-methods-and-applications
#10
Erin Adamson, Kai Ludwig, David Mummy, Sean B Fain
In the past decade, hyperpolarized (HP) contrast agents have been under active development for MRI applications to address the twin challenges of functional and quantitative imaging. Both HP helium (<sup>3</sup>He) and xenon (<sup>129</sup>Xe) gases have reached the stage where they are under study in clinical research. HP <sup>129</sup>Xe, in particular, is poised for larger scale clinical research to investigate asthma, chronic obstructive pulmonary disease, and fibrotic lung diseases...
April 6, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28380874/high-energy-few-cycle-yb-doped-fiber-amplifier-source-based-on-a-single-nonlinear-compression-stage
#11
L Lavenu, M Natile, F Guichard, Y Zaouter, M Hanna, E Mottay, P Georges
A simple, compact, and efficient few-cycle laser source at a central wavelength of 1 µm is presented. The system is based on a high-energy femtosecond ytterbium-doped fiber amplifier delivering 130 fs, 250 µJ pulses at 200 kHz, corresponding to 1.5 GW of peak power and an average power of 50 W. The unprecedented short pulse duration at the output of this system is obtained by use of spectral intensity and phase shaping, allowing for both gain narrowing mitigation and the compensation of the nonlinear accumulated spectral phase...
April 3, 2017: Optics Express
https://www.readbyqxmd.com/read/28368505/effects-of-cranioplasty-on-cerebral-blood-flow-following-decompressive-craniectomy-a-systematic-review-of-the-literature
#12
Sameer H Halani, Jason K Chu, James G Malcolm, Rima S Rindler, Jason W Allen, Jonathan A Grossberg, Gustavo Pradilla, Faiz U Ahmad
BACKGROUND: Cranioplasty after decompressive craniectomy (DC) is routinely performed for reconstructive purposes and has been recently linked to improved cerebral blood flow (CBF) and neurological function. OBJECTIVE: To systematically review all available literature to evaluate the effect of cranioplasty on CBF and neurocognitive recovery. METHODS: A PubMed, Google Scholar, and MEDLINE search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines included studies reporting patients who underwent DC and subsequent cranioplasty in whom cerebral hemodynamics were measured before and after cranioplasty...
March 29, 2017: Neurosurgery
https://www.readbyqxmd.com/read/28362453/the-origin-of-the-measured-chemical-shift-of-129-xe-in-uio-66-and-uio-67-revealed-by-dft-investigations
#13
Kai Trepte, Jana Schaber, Sebastian Schwalbe, Franziska Drache, Irena Senkovska, Stefan Kaskel, Jens Kortus, Eike Brunner, Gotthard Seifert
The NMR chemical shift of the xenon isotope (129)Xe inside the metal-organic frameworks (MOFs) UiO-66 and UiO-67 (UiO - University of Oslo) has been investigated both with density functional theory (DFT) and in situ high-pressure (129)Xe NMR measurements. The experiments reveal a decrease of the total chemical shift comparing the larger isoreticular MOF (UiO-67) with the smaller one (UiO-66), even though one may expect an increase due to the higher amount of adsorbed Xe atoms. We are able to calculate contributions to the chemical shift individually...
April 12, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28361248/increased-risk-of-critical-cbf-levels-in-sah-patients-with-actual-cpp-below-calculated-optimal-cpp
#14
Ulf Johnson, Henrik Engquist, Anders Lewén, Tim Howells, Pelle Nilsson, Elisabeth Ronne-Engström, Elham Rostami, Per Enblad
BACKGROUND: Cerebral pressure autoregulation can be quantified with the pressure reactivity index (PRx), based on the correlation between blood pressure and intracranial pressure. Using PRx optimal cerebral perfusion pressure (CPPopt) can be calculated, i.e., the level of CPP where autoregulation functions best. The relation between cerebral blood flow (CBF) and CPPopt has not been examined. The objective was to assess to which extent CPPopt can be calculated in SAH patients and to investigate CPPopt in relation to CBF...
March 30, 2017: Acta Neurochirurgica
https://www.readbyqxmd.com/read/28359970/aryl-or-heteroaryl-based-hydrazinylphthalazine-derivatives-as-new-potential-antitrypanosomal-agents
#15
Angel H Romero, Jonathan Rodríguez, Yael García-Marchan, Jacques Leañez, Xenón Serrano-Martín, Simón E López
A series of twenty phthalazinyl-hydrazones were synthesized and tested as potential anti-Trypanosoma cruzi agents. The phthalazines containing 5-nitroheteroaryl moiety 3l and 3m displayed an excellent in vitro antitrypanosomal profile, exhibiting low micromolar EC50 values against proliferative epimastigote of T. cruzi and minimal toxicity toward Vero cells. These derivatives were more potent than the reference drug benznidazole against the epimastigote stage of the parasite. Structure-property analysis indicates that the highly conjugated 5-nitroheteroaryl moiety connected to the phthalazin scaffold play an important role in the antichagasic activity of these phthalazines...
March 21, 2017: Bioorganic Chemistry
https://www.readbyqxmd.com/read/28341262/pulsed-xenon-ultraviolet-light-disinfection-in-a-burn-unit-impact-on-environmental-bioburden-multidrug-resistant-organism-acquisition-and-healthcare-associated-infections
#16
Caroline Green, Jeremy C Pamplin, Kristine N Chafin, Clinton K Murray, Heather C Yun
Portable pulsed xenon ultraviolet disinfection (PPX-UVD) may reduce healthcare associated infections (HAI). There is limited data to inform use in burn intensive care units (BICU), where multidrug-resistant organisms (MDRO), especially gram negative rods (GNR), commonly cause disease. We evaluated PPX-UVD effects on environmental bioburden and rates of HAI and MDRO acquisition in a BICU. PPX-UVD was used for 3 months after standard cleaning of patient and operating rooms (ORs). Settle and touch plates in patient rooms and ORs were obtained after standard cleaning, pre-and post-PPX-UVD...
March 2017: Burns: Journal of the International Society for Burn Injuries
https://www.readbyqxmd.com/read/28339273/search-for-electronic-recoil-event-rate-modulation-with-4-years-of-xenon100-data
#17
E Aprile, J Aalbers, F Agostini, M Alfonsi, F D Amaro, M Anthony, F Arneodo, P Barrow, L Baudis, B Bauermeister, M L Benabderrahmane, T Berger, P A Breur, A Brown, E Brown, S Bruenner, G Bruno, R Budnik, L Bütikofer, J Calvén, J M R Cardoso, M Cervantes, D Cichon, D Coderre, A P Colijn, J Conrad, J P Cussonneau, M P Decowski, P de Perio, P Di Gangi, A Di Giovanni, S Diglio, G Eurin, J Fei, A D Ferella, A Fieguth, D Franco, W Fulgione, A Gallo Rosso, M Galloway, F Gao, M Garbini, C Geis, L W Goetzke, Z Greene, C Grignon, C Hasterok, E Hogenbirk, R Itay, B Kaminsky, G Kessler, A Kish, H Landsman, R F Lang, D Lellouch, L Levinson, Q Lin, S Lindemann, M Lindner, J A M Lopes, A Manfredini, I Maris, T Marrodán Undagoitia, J Masbou, F V Massoli, D Masson, D Mayani, M Messina, K Micheneau, B Miguez, A Molinario, M Murra, J Naganoma, K Ni, U Oberlack, P Pakarha, B Pelssers, R Persiani, F Piastra, J Pienaar, V Pizzella, M-C Piro, G Plante, N Priel, L Rauch, S Reichard, C Reuter, A Rizzo, S Rosendahl, N Rupp, J M F Dos Santos, G Sartorelli, M Scheibelhut, S Schindler, J Schreiner, M Schumann, L Scotto Lavina, M Selvi, P Shagin, M Silva, H Simgen, M V Sivers, A Stein, D Thers, A Tiseni, G Trinchero, C Tunnell, H Wang, Y Wei, C Weinheimer, J Wulf, J Ye, Y Zhang
We report on a search for electronic recoil event rate modulation signatures in the XENON100 data accumulated over a period of 4 yr, from January 2010 to January 2014. A profile likelihood method, which incorporates the stability of the XENON100 detector and the known electronic recoil background model, is used to quantify the significance of periodicity in the time distribution of events. There is a weak modulation signature at a period of 431_{-14}^{+16} day in the low energy region of (2.0-5.8) keV in the single scatter event sample, with a global significance of 1...
March 10, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28325351/flexible-fiber-optic-high-speed-imaging-of-vocal-fold-vibration-a-preliminary-report
#18
Peak Woo, Peter Baxter
OBJECTIVE: High-speed video (HSV) imaging of vocal fold vibration has been possible only through the rigid endoscope. This study reports that a fiberscope-based high-speed imaging system may allow HSV imaging of naturalistic voicing. MATERIALS AND METHODS: Twenty-two subjects were recorded using a commercially available black and white high-speed camera (Photron Motion Tools, 256 × 120 pixel, 2000 frames per second, 8 second acquisition time). The camera gain is set to +6 db...
March 2017: Journal of Voice: Official Journal of the Voice Foundation
https://www.readbyqxmd.com/read/28323916/acute-hypercortisolemia-exerts-depot-specific-effects-on-abdominal-and-femoral-adipose-tissue-function
#19
Konstantinos N Manolopoulos, Michael W O'Reilly, Iwona J Bujalska, Jeremy W Tomlinson, Wiebke Arlt
Context: Glucocorticoids have pleiotropic metabolic functions, and acute glucocorticoid excess affects fatty acid metabolism, increasing systemic lipolysis. Whether glucocorticoids exert adipose tissue depot-specific effects remains unclear. Objective: To provide an in vivo assessment of femoral and abdominal adipose tissue responses to acute glucocorticoid administration. Design and Outcome Measures: Nine healthy male volunteers were studied on two occasions, after a hydrocortisone infusion (0...
April 1, 2017: Journal of Clinical Endocrinology and Metabolism
https://www.readbyqxmd.com/read/28298006/nuclear-magnetic-resonance-diffusion-pore-imaging-experimental-phase-detection-by-double-diffusion-encoding
#20
Kerstin Demberg, Frederik Bernd Laun, Johannes Windschuh, Reiner Umathum, Peter Bachert, Tristan Anselm Kuder
Diffusion pore imaging is an extension of diffusion-weighted nuclear magnetic resonance imaging enabling the direct measurement of the shape of arbitrarily formed, closed pores by probing diffusion restrictions using the motion of spin-bearing particles. Examples of such pores comprise cells in biological tissue or oil containing cavities in porous rocks. All pores contained in the measurement volume contribute to one reconstructed image, which reduces the problem of vanishing signal at increasing resolution present in conventional magnetic resonance imaging...
February 2017: Physical Review. E
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