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https://www.readbyqxmd.com/read/28101404/model-for-indirect-laser-surgery
#1
Natalia Sapogova, Vladimir Bredikhin, Nikita Bityurin, Vladislav Kamensky, Vjacheslav Zhigarcov, Vladimir Yusupov
We present a theoretical model for laser cutting of biological tissue by a strongly heated fiber tip with a highly absorbing coating. A significant dependence of the cutting speed and cutting depth on the inclination angle of the scalpel to the surface when scattering exceeds absorption in the biological tissue is shown. Experimental evidences of this effect are presented. In the experiment, we used silica fiber with coating made of carbon and silicon organic varnish, the 0.97-µm wavelength laser and porcine skin...
January 1, 2017: Biomedical Optics Express
https://www.readbyqxmd.com/read/28101130/silica-titania-xerogel-doped-with-mo-p-heteropoly-compounds-for-solid-phase-spectrophotometric-determination-of-ascorbic-acid-in-fruit-juices-pharmaceuticals-and-synthetic-urine
#2
Maria A Morosanova, Elena I Morosanova
BACKGROUND: Ascorbic acid is one of the most important vitamins to monitor in dietary sources (juices and vitamins) and biological liquids. RESULTS: Silica and silica-titania xerogels doped with Mo,P-heteropoly compounds (HPC) have been synthesized varying titanium(IV) and HPC content in sol. Their surface area and porosity have been studied with nitrogen adsorption and scanning electron microscopy, their elemental composition has been studied with energy-dispersive X-ray analysis...
2017: Chemistry Central Journal
https://www.readbyqxmd.com/read/28100887/production-of-a-health-beneficial-food-emulsifier-by-enzymatic-partial-hydrolysis-of-phospholipids-obtained-from-the-head-of-autumn-chum-salmon
#3
A K M Azad Shah, Toshihiro Nagao, Hideyuki Kurihara, Koretaro Takahashi
Phospholipids and their partial hydrolysates, namely lysophospholipids (LPLs), have been widely used in food, pharmaceutical, and cosmetic products as highly efficient emulsifiers. This study was conducted to produce docosahexaenoic acid (DHA)-esterified LPLs by enzymatic modification of phospholipids obtained from the head of autumn chum salmon (Oncorhynchus keta). The emulsifying properties of the obtained LPLs were also evaluated. Two different types of substrates of salmon head phospholipids were prepared via silica gel and cold acetone precipitation...
January 18, 2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/28100048/unanticipated-stickiness-of-%C3%AE-pinene
#4
Hilary M Chase, Junming Ho, Mary Alice Upshur, Regan J Thomson, Victor S Batista, Franz M Geiger
Hilary M. Chase1#, Junming Ho2#, Mary Alice Upshur1, Regan J. Thomson1, Victor S. Batista3, Franz M. Geiger1* 1Department of Chemistry, Northwestern University, Evanston, IL. 60208, United States; 2 Agency for Science, Technology and Research, Institute of High Performance Computing, 1 Fusionopolis Way #16-16 Connexis North, Singapore 138632; 3Department of Chemistry, Yale University, P.O. Box 208107, New Haven, CT. 06520, United States # These authors contributed equally to this work. *corresponding author: geigerf@chem...
January 19, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28099024/surface-interactions-and-confinement-of-methane-a-high-pressure-magic-angle-spinning-nmr-and-computational-chemistry-study
#5
Salim Ok, David W Hoyt, Amity Andersen, Julie Sheets, Susan A Welch, David R Cole, Karl Todd Mueller, Nancy M Washton
Characterization and modeling of the molecular-level behavior of simple hydrocarbon gases, such as methane, in the presence of both nonporous and nano-porous mineral matrices allows for predictive understanding of important processes in engineered and natural systems. In this study, changes in local electromagnetic environments of the carbon atoms in methane under conditions of high pressure (up to 130 bar) and moderate temperature (up to 346 K) were observed with 13C magic-angle spinning (MAS) NMR spectroscopy while the methane gas was mixed with two model solid substrates: a fumed non-porous, 12 nm particle size silica and a mesoporous silica with 200 nm particle size and 4 nm average pore diameter...
January 18, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28098970/strong-enhancement-of-photoelectric-conversion-efficiency-of-co-hybridized-polymer-solar-cell-by-silver-nanoplates-and-core-shell-nanoparticles
#6
Wenfei Shen, Jianguo Tang, Yao Wang, Jixian Liu, Linjun Huang, Weichao Chen, Lanlan Yang, Wei Wang, Yanxin Wang, Renqiang Yang, Jungheum Yun, Laurence A Belfiore
A new way was meticulously designed to utilize the localized surface plasmon resonance (LSPR) effect and the light scattering effect of silver nanoplate (Ag-nPl) and core-shell Ag@SiO2 nanoparticles (Ag@SiO2-NPs) to enhance the photovoltaic performances of polymer solar cells (PSCs). To prevent direct contact between silver nanoparticles (Ag-NPs) and photo-active materials which will cause electrons quenching, bare Ag-nPl were spin-coated on indium tin oxide and silica capsulated Ag-NPs were incorporated to PBDTTT-C-T:PC71BM active layer...
January 18, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28098840/comparative-solid-state-stability-of-perindopril-active-substance-vs-pharmaceutical-formulation
#7
Valentina Buda, Minodora Andor, Adriana Ledeti, Ionut Ledeti, Gabriela Vlase, Titus Vlase, Carmen Cristescu, Mirela Voicu, Liana Suciu, Mirela Cleopatra Tomescu
This paper presents the results obtained after studying the thermal stability and decomposition kinetics of perindopril erbumine as a pure active pharmaceutical ingredient as well as a solid pharmaceutical formulation containing the same active pharmaceutical ingredient (API). Since no data were found in the literature regarding the spectroscopic description, thermal behavior, or decomposition kinetics of perindopril, our goal was the evaluation of the compatibility of this antihypertensive agent with the excipients in the tablet under ambient conditions and to study the effect of thermal treatment on the stability of perindopril erbumine...
January 15, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28097753/fully-copper-exchanged-high-silica-lta-zeolites-as-unrivaled-hydrothermally-stable-nh3-scr-catalysts
#8
Taekyung Ryu, Nak Ho Ahn, Seungwan Seo, Jung Cho, Hyojun Kim, Donghui Jo, Gi Tae Park, Pyung Soon Kim, Chang Hwan Kim, Elliott L Bruce, Paul A Wright, In-Sik Nam, Suk Bong Hong
Diesel engine technology is still the most effective solution to meet tighter CO2 regulations in the mobility and transport sector. In implementation of fuel-efficient diesel engines, the poor thermal durability of lean nitrogen oxides (NOx ) aftertreatment systems remains as one major technical hurdle. Divalent copper ions when fully exchanged into high-silica LTA zeolites are demonstrated to exhibit excellent activity maintenance for NOx reduction with NH3 under vehicle simulated conditions even after hydrothermal aging at 900 °C, a critical temperature that the current commercial Cu-SSZ-13 catalyst cannot overcome owing to thermal deactivation...
January 18, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28097273/integration-of-multiple-active-sites-on-large-pore-mesoporous-silica-for-enantioselective-tandem-reactions
#9
Xuelin Xia, Jingjing Meng, Hanxin Wu, Tanyu Cheng, Guohua Liu
Facile construction of a multifunctional heterogeneous catalyst through the assembly of Au/carbene and chiral ruthenium/diamine dual complexes in large-pore mesoporous silica was developed. This enables an efficient one-pot hydration-asymmetric transfer hydrogenation enantioselective tandem reaction of haloalkynes, affording chiral halohydrins with up to 99% enantioselectivity. Combined multifunctionalities, such as substrate-promoted silanol-functionality, BF4(-) anion-bonding gold/carbene and covalent-bonding chiral ruthenium/diamine active centers, contributed cooperatively to the catalytic performance...
January 18, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28094955/using-diffusion-to-characterize-interfacial-heterogeneity
#10
Krystyna Kijewska, Gary J Blanchard
We report on the use of molecular diffusional motion over a range of length scales to characterize compositional heterogeneity in monolayer structures. This work focuses on the diffusional motion of perylene in two types of films supported on functionalized silica surfaces; single component (stearic acid) and two-component (hydrocarbon/fluorocarbon) films. Langmuir-Blodgett (LB) monolayers were deposited directly on silica or were bound to surface-modified silica by means of metal ion complexation. The LB films were characterized by their π-A isotherms and by Brewster angle microscopy (BAM) during formation and deposition...
January 17, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28094535/comparing-the-coral-and-random-forest-approaches-for-modelling-the-in-vitro-cytotoxicity-of-silica-nanomaterials
#11
Antonio Cassano, Richard L Marchese Robinson, Anna Palczewska, Tomasz Puzyn, Agnieszka Gajewicz, Lang Tran, Serena Manganelli, Mark T D Cronin
Nanotechnology is one of the most important technological developments of the 21st century. In silico methods to predict toxicity, such as quantitative structure-activity relationships (QSARs), promote the safe-by-design approach for the development of new materials, including nanomaterials. In this study, a set of cytotoxicity experimental data corresponding to 19 data points for silica nanomaterials were investigated, to compare the widely employed CORAL and Random Forest approaches in terms of their usefulness for developing so-called 'nano-QSAR' models...
December 2016: Alternatives to Laboratory Animals: ATLA
https://www.readbyqxmd.com/read/28094400/synthesis-of-3-azabicyclo-3-1-0-hexane-derivatives-via-palladium-catalyzed-cyclopropanation-of-maleimides-with-n-tosylhydrazones-practical-and-facile-access-to-cp-866-087
#12
Pengquan Chen, Chuanle Zhu, Rui Zhu, Zhiming Lin, Wanqing Wu, Huanfeng Jiang
A palladium-catalyzed cyclopropanation of internal alkenes with N-tosylhydrazones is presented. This gram-scale cyclopropanation reaction of maleimides provides a wide spectrum of 3-azabicyclo[3.1.0]hexane derivatives in high yields and diastereoselectivities. The major diastereoisomers could be easily isolated by chromatography on silica gel. This protocol provides a practical route to the mu opioid receptor antagonist CP-866,087.
January 17, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28094308/silicon-availability-modifies-nutrient-use-efficiency-and-content-c-n-p-stoichiometry-and-productivity-of-winter-wheat-triticum-aestivum-l
#13
Silke Neu, Jörg Schaller, E Gert Dudel
Silicon (Si) is known as beneficial element for graminaceous plants. The importance of Si for plant functioning of cereals was recently emphasized. However, about the effect of Si availability on biomass production, grain yield, nutrient status and nutrient use efficiency for wheat (Triticum aestivum L.), as one of the most important crop plants worldwide, less is known so far. Consequently, we assessed the effect of a broad range of supply levels of amorphous SiO2 on wheat plant performance. Our results revealed that Si is readily taken up and accumulated basically in aboveground vegetative organs...
January 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28094240/ectopic-bone-formation-by-gel-derived-bioactive-glass-poly-l-lactide-co-glycolide-composites-in-a-rabbit-muscle-model
#14
Joanna Filipowska, Katarzyna Cholewa-Kowalska, Jarosław Wieczorek, Danuta Semik, Zbigniew Dąbrowski, Maria Łączka, Anna M Osyczka
In this study we aimed to assess the in vivo osteoinductive properties of two composite scaffolds made of PLGA (poly-L-lactide-co-glycolide) and two types of gel-derived bioactive glasses, namely a high silica S2 bioactive glass (S2-PLGA composites) or high lime A2 bioactive glass (A2-PLGA composites). To achieve that, the potential of the composites to induce ectopic bone formation in a rabbit muscle has been examined along with the control PLGA scaffold. Cylinder-like scaffolds of 7  ×  3 mm (width  ×  height) were implanted into pouches created in the latissimus dorsi muscle of 18 New Zealand rabbits...
January 17, 2017: Biomedical Materials
https://www.readbyqxmd.com/read/28094023/monodisperse-silica-filled-composite-restoratives-mechanical-and-light-transmission-properties
#15
Eric Habib, Ruili Wang, X X Zhu
OBJECTIVES: The aim of this study was to formulate resin-based composites using spherical silica particulate fillers with graded size (75, 150, 350, 500, and 1000nm), and to evaluate the influence of their size and loading on the mechanical and light transmission properties of the resulting material. METHODS: A series of five spherical silica fillers were synthesized, and then formulated with BisGMA/TEGDMA or UDMA/TEGDMA resins. These were then tested for maximum filler loading, flexural strength and modulus, as well as transparency and depth of cure...
January 13, 2017: Dental Materials: Official Publication of the Academy of Dental Materials
https://www.readbyqxmd.com/read/28093898/effect-of-heat-treatment-on-the-nitrogen-content-and-its-role-on-the-co2-adsorption-capacity-of-highly-ordered-mesoporous-carbon-nitride
#16
Kripal S Lakhi, Dae-Hwan Park, Stalin Joseph, Siddulu N Talapaneni, Ugo Ravon, Khalid Al-Bahily, Ajayan Vinu
Mesoporous carbon nitrides (MCN) with rod shaped morphology and tunable nitrogen contents have been synthesized via calcination free method using ethanol-washed mesoporous SBA-15 as templates at different carbonization temperatures. Carbon tetrachloride (CTC) and ethylenediamine (EDA) were used as the sources of carbon and nitrogen respectively. The resulting MCN materials were characterized with low and high angle power XRD, N2 adsorption, HR-SEM, HR-TEM, CHN elemental analysis, XPS and. XANES techniques. It is observed that the carbonization temperature plays a critical role in controlling not only the crystallinity but also the nitrogen content and the textural parameters of the samples including specific surface area and specific pore volume...
January 16, 2017: Chemistry, An Asian Journal
https://www.readbyqxmd.com/read/28092076/determination-of-trace-elements-in-cow-placenta-by-tungsten-coil-atomic-emission-spectrometry
#17
Daniel A Gonçalves, Ana C Soncin, George L Donati, Mirian C Dos Santos
Tungsten coil atomic emission spectrometry (WCAES) is used to determine trace levels of Mn (403.1 nm) and Cr (425.5 nm) in cow placenta. All samples were collected in Ilha Solteira, SP, Brazil. The instrumental setup is based on a tungsten filament extracted from 150 W, 15 V microscope light bulbs, a solid state power supply, fused silica lens, crossed Czerny-Turner spectrograph, and a thermoelectrically cooled charge-coupled device detector. The limits of detection (LOD) and quantification (LOQ) for Cr are 2 and 8 μg L(-1), and 20 and 60 μg L(-1) for Mn, respectively...
January 16, 2017: Biological Trace Element Research
https://www.readbyqxmd.com/read/28091890/a-theoretical-study-of-the-inhibition-effect-of-pamam-molecule-on-silica-scale
#18
Chunyu Chen, Ni Bai, Yan Zhang, Lina Jiao, Mingzhu Xia, Gang Chen
In this work, the molecular modeling method was performed to study adsorption interaction between PAMAM molecules of different generations and silicic acid molecules, and the inhibition effect on silica scale were discussed. The results show that adsorption energies of PAMAM molecule of generation 1.0 with amine-terminated groups are stronger than those of generation 1.5 with terminated carboxyl group. The composition of adsorption interactions are the dominating electrostatic interactions and van de Waals interactions as well as H-bond interactions...
January 2017: Journal of Molecular Modeling
https://www.readbyqxmd.com/read/28091808/occupational-and-environmental-scleroderma-systematic-review-and-meta-analysis
#19
Manuel Rubio-Rivas, Rafael Moreno, Xavier Corbella
The etiology of systemic sclerosis (SSc) remains unknown; however, several occupational and environmental factors have been implicated. Our objective was to perform a meta-analysis of all studies published on SSc associated with occupational and environmental exposure. The review was undertaken by means of MEDLINE and SCOPUS from 1960 to 2014 and using the terms: "systemic," "scleroderma," or "systemic sclerosis/chemically induced" [MesH]. The Newcastle-Ottawa Scale was used for the qualifying assessment. The inverse variance-weighted method was performed...
January 14, 2017: Clinical Rheumatology
https://www.readbyqxmd.com/read/28090036/fabrication-and-functionalization-of-inorganic-materials-using-amphiphilic-molecules
#20
Hirobumi Shibata
In this review, the synthesis of inorganic materials with various properties using amphiphilic molecules is examined. Amphiphilic molecules are used for the formation of highly ordered mesostructures and the surface modification. Two examples of the mesostructures are crystalline mesoporous titania (TiO2) and the novel visible light responsive mesostuructured titania modified with dye in the pores, which can be fabricated using the molecular self-assemblies of amphiphiles as templates. Surface modification using amphiphilic molecules enables the construction of self-assembled arrays of silica particles and the preparation of a film that can control adsorption/desorption behavior of bovine serum albumin (BSA) by light irradiation...
January 16, 2017: Journal of Oleo Science
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