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https://www.readbyqxmd.com/read/28448049/controlled-release-of-chlorine-dioxide-in-a-perforated-packaging-system-to-extend-the-storage-life-and-improve-the-safety-of-grape-tomatoes
#1
Xiuxiu Sun, Elizabeth Baldwin, Anne Plotto, Jan Narciso, Christopher Ference, Mark Ritenour, Ken Harrison, Joseph Gangemi, Jinhe Bai
A controlled-release chlorine dioxide (ClO2) pouch was developed by sealing a slurry form of ClO2 into semipermeable polymer film; the release properties of the pouch were monitored in containers with or without fruit. The pouch was affixed to the inside of a perforated clamshell containing grape tomatoes, and the effect on microbial population, firmness, and weight loss was evaluated during a 14 day storage period at 20 °C. Within 3 days, the ClO2 concentration in the clamshells reached 3.5 ppm and remained constant until day 10...
April 7, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28447883/c-h-infrared-absorption-and-solubility-of-ethylene-propyne-2-methyl-2-butene-and-2-methyl-1-3-butadiene-isoprene-in-liquid-argon-solutions
#2
Parashu R Nyaupane, Helena Diez-Y-Riega, Daniel Cordier, Carlos E Manzanares
The solubility of ethylene (H2C=CH2), propyne (CH3-C≡C-H), 2-methyl-2-butene (CH3-CH=C(CH3)2), and isoprene or 2-methyl-1, 3-butadiene (H2C=C(CH3)-CH=CH2) in liquid argon has been measured using mid-infrared and near-infrared (NIR) absorption. Spectra were recorded in the C-H infrared (IR) region. Spectra were obtained at increasing solution composition until the magnitude of the integrated absorption band reached a maximum value, indicating a saturated solution. The approximate experimental solubilities are: (600 ± 100) ppm at 92 K for ethylene, (22 ± 9) ppm at 100 K for propyne, (9 ± 5) ppm at 100 K for 2-methyl-2-butene, and (12 ± 2) ppm at 86 K for isoprene...
January 1, 2017: Applied Spectroscopy
https://www.readbyqxmd.com/read/28447482/quantitative-potassium-measurements-with-laser-induced-breakdown-spectroscopy-using-low-energy-lasers-application-to-in-situ-k-ar-geochronology-for-planetary-exploration
#3
Yuichiro Cho, Misa Horiuchi, Kazuo Shibasaki, Shingo Kameda, Seiji Sugita
In situ radiogenic isotope measurements to obtain the absolute age of geologic events on planets are of great scientific value. In particular, K-Ar isochrons are useful because of their relatively high technical readiness and high accuracy. Because this isochron method involves spot-by-spot K measurements using laser-induced breakdown spectroscopy (LIBS) and simultaneous Ar measurements with mass spectrometry, LIBS measurements are conducted under a high vacuum condition in which emission intensity decreases significantly...
January 1, 2017: Applied Spectroscopy
https://www.readbyqxmd.com/read/28447477/simultaneous-visualization-of-hydrogen-peroxide-and-water-concentrations-using-photofragmentation-laser-induced-fluorescence
#4
Kajsa Larsson, Marcus Aldén, Joakim Bood
A concept based on photofragmentation laser-induced fluorescence (PFLIF) is for the first time demonstrated for simultaneous detection of hydrogen peroxide (H2O2) and water (H2O) vapor in various mixtures containing the two constituents in a bath of argon gas. A photolysis laser pulse at 248 nm dissociates H2O2 into OH fragments, whereupon a probe pulse, delayed 100 ns and tuned to an absorption line in the A(2)Σ(+) (v = 1) ← X(2)Π(v = 0) band of OH near 282 nm, induces fluorescence. The total OH fluorescence reflects the H2O2 concentration, while its spectral shape is utilized to determine the H2O concentration via a model predicting the ratio between the fluorescence intensities of the A(2)Σ(+) (v = 1) → X(2)Π(v = 1) and the A(2)Σ(+) (v = 0) → X(2)Π(v = 0) bands...
January 1, 2017: Applied Spectroscopy
https://www.readbyqxmd.com/read/28447152/expression-changes-in-metal-resistance-genes-in-microbacterium-liquefaciens-under-nickel-and-vanadium-exposure
#5
Grisel Fierros-Romero, José A Wrosek-Cabrera, Marlenne Gómez-Ramírez, Reynaldo C Pless, A M Rivas-Castillo, Norma G Rojas-Avelizapa
Microbacterium liquefaciens MNSH2-PHGII-2 is a nickel-vanadium-resistant bacterium isolated from mine tailings located in Guanajuato, Mexico. In PHGII liquid media, M. liquefaciens has the ability to remove 29.5 ppm of Ni and 168.3 ppm of V. The present study reports, for the first time in M. liquefaciens, the presence of the genes nccA (Ni-Co-Cd resistance), hant (high-affinity nickel transporter), smtA, a metal-binding protein gene, and VAN2 (V resistance), which showed an increased expression under exposure to 200 ppm of Ni and 200 ppm of V during the logarithmic growth phase of the microorganism in PHGII liquid media...
April 27, 2017: Current Microbiology
https://www.readbyqxmd.com/read/28444591/biotechnological-application-of-sustainable-biogas-production-through-dry-anaerobic-digestion-of-napier-grass
#6
Natthawud Dussadee, Rameshprabu Ramaraj, Tapana Cheunbarn
Napier grass (Pennisetum purpureum), represents an interesting substrate for biogas production. The research project evaluated biogas potential production from dry anaerobic digestion of Napier grass using batch experiment. To enhance the biogas production from ensiled Napier grass, thermal and alkaline pre-treatments were performed in batch mode. Alkali hydrolysis of Napier grass was performed prior to batch dry anaerobic digestion at three different mild concentrations of sodium hydroxide (NaOH). The study results confirmed that NaOH pretreated sample produced high yield of biogas than untreated (raw) and hot water pretreated samples...
May 2017: 3 Biotech
https://www.readbyqxmd.com/read/28443936/effects-of-graphene-defects-on-gas-sensing-properties-towards-no2-detection
#7
Filiberto Ricciardella, Sten Vollebregt, Tiziana Polichetti, Mario Miscuglio, Brigida Alfano, Maria L Miglietta, Ettore Massera, Girolamo Di Francia, Pasqualina M Sarro
The crystal structure of graphene flakes is expected to significantly affect their sensing properties. Here we report an experimental investigation on the crystalline structure of graphene aimed at exploring the effects on the gas sensing properties. The morphology of graphene, prepared via Chemical Vapor Deposition (CVD), Liquid Phase Exfoliation (LPE) and Mechanical Exfoliation (ME), is inspected through Raman spectroscopy, Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). CVD and LPE-graphene structures are found to be more defective with respect to ME-graphene...
April 26, 2017: Nanoscale
https://www.readbyqxmd.com/read/28442723/effects-of-elevated-co2-on-the-fitness-and-potential-population-damage-of-helicoverpa-armigera-based-on-two-sex-life-table
#8
Jinping Liu, Wenkun Huang, Hsin Chi, Chonghui Wang, Hongxia Hua, Gang Wu
We evaluated the direct effects of three different atmospheric CO2 concentrations (380 ppm, 550 ppm and 750 ppm) on the population parameters of the cotton bollworm, Helicoverpa armigera fed an artificial diet. The life history and fitness of H. armigera were analyzed using an age-stage, two-sex life table. Our results showed significantly longer larval durations and lower female pupal weight under elevated CO2 than under ambient CO2. Additionally, the fecundity of H. armigera was lower under elevated CO2 than under ambient CO2...
April 25, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28441553/determination-of-critical-operational-conditions-favoring-sulfide-production-from-domestic-wastewater-treated-by-a-sulfur-utilizing-denitrification-process
#9
L Ghorbel, L Coudert, Y Gilbert, G Mercier, J F Blais
The aim of this study was to determine the critical operational conditions leading to the generation of sulfide in a domestic wastewater treated by a sulfur-utilizing denitrification process. The influence of various important parameters on the reduction of the sulfates present in denitrified domestic wastewaters to sulfide was studied. Experiments were carried out in batch mode with denitrified domestic wastewaters containing various amounts of both organic matter and sulfates. Preliminary results showed that aqueous sulfide was generated for DOC and sulfate contents higher than 56 mg/L and 371 mg/L, respectively, while DOC and sulfate contents of 77 mg/L and 412 mg/L, respectively, were required to allow the release of gaseous H2S...
April 22, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28441022/a-low-valent-lead-hydride-and-its-extreme-low-field-1h-nmr-chemical-shift
#10
Julia Schneider, Christian Patrick Sindlinger, Klaus Eichele, Hartmut Schubert, Lars Wesemann
Although hydrides of the group 14 elements are well known as versatile starting materials in many chemical transformations, a hydride of lead in oxidation state II is so far unknown. In this work we finally complete the jigsaw puzzle by reporting the isolation of the first low valent organolead hydride. The thermolabile dimeric organolead hydride was synthesized at low temperature and fea-tures a hydride 1H NMR signal (in solution 35.61 ppm; in the solid state 31.1 ppm) at the lowest field observed so far for a diamagnetic compound in agreement with quantum chemical predictions...
April 25, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28440982/-intelligence-quotient-loss-in-mexican-pottery-artisan-s-children
#11
Daniel Estrada-Sánchez, Bret Ericson, Cuauhtémoc Arturo Juárez-Pérez, Guadalupe Aguilar-Madrid, Lina Hernández, Sandra Gualtero, Jack Caravanos
BACKGROUND: In Mexico, artisans frequently use lead oxide or greta in order to produce utensils, which are destined to preparation and storage of food and drinks. Additionally, the risk of lead poisoning of artisans and their families is greater than in general population, and within these families, children are the most susceptible to lead poisoning. The aim of this study was to estimate IQ loss in Mexican children from potter families exposed to lead. METHODS: Lead concentrations in soil were determined in 19 potter's homes that functioned as pottery workshops in seven Mexican states between 2009 and 2012...
May 2017: Revista Médica del Instituto Mexicano del Seguro Social
https://www.readbyqxmd.com/read/28440621/gas-phase-sensing-of-alcohols-by-metal-organic-framework-polymer-composite-materials
#12
Sumit Sachdeva, Sander J H Koper, Anahid Sabetghadam, Dimitri Soccol, Dirk J Gravesteijn, Freek Kapteijn, Ernst J R Sudhölter, Jorge Gascon, Louis C P M de Smet
Affinity layers play a crucial role in chemical sensors for the selective and sensitive detection of analytes. Here, we report the use of composite affinity layers containing Metal Organic Frameworks (MOFs) in a polymeric matrix for sensing purposes. Nanoparticles of NH2-MIL-53(Al) were dispersed in a Matrimid polymer matrix with different weight ratios (0-100 wt %) and drop-casted on planar capacitive transducer devices. These coated devices were electrically analyzed using impedance spectroscopy and investigated for their sensing properties toward the detection of a series of alcohols and water in the gas phase...
April 25, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28440601/measurement-of-exhaled-breath-carbon-monoxide-in-clinical-practice-a-study-of-levels-in-central-pennsylvania-community-members
#13
Shari Hrabovsky, Jessica M Yingst, Susan Veldheer, Erin Hammett, Jonathan Foulds
BACKGROUND AND PURPOSE: Exhaled breath carbon monoxide (eBCO) reading is a useful tool for nurse practitioners to evaluate smoking status and other exposures to carbon monoxide (CO) to identify risk for cancer and chronic disease. This study aimed to measure one community's eBCO and identify potential environmental factors that may affect eBCO among nonsmokers. METHODS: Data collected by convenience sampling at community health events included self-reported tobacco use and potential CO exposure...
April 25, 2017: Journal of the American Association of Nurse Practitioners
https://www.readbyqxmd.com/read/28440003/advanced-sers-sensor-based-on-capillarity-assisted-preconcentration-through-gold-nanoparticle-decorated-porous-nanorods
#14
Longjian Xue, Wei Xie, Leonie Driessen, Katrin F Domke, Yong Wang, Sebastian Schlücker, Stanislav N Gorb, Martin Steinhart
A preconcentrating surface-enhanced Raman scattering (SERS) sensor for the analysis of liquid-soaked tissue, tiny liquid droplets and thin liquid films without the necessity to collect the analyte is reported. The SERS sensor is based on a block-copolymer membrane containing a spongy-continuous pore system. The sensor's upper side is an array of porous nanorods having tips functionalized with Au nanoparticles. Capillarity in combination with directional evaporation drives the analyte solution in contact with the flat yet nanoporous underside of the SERS sensor through the continuous nanopore system toward the nanorod tips where non-volatile components of the analyte solution precipitate at the Au nanoparticles...
April 25, 2017: Small
https://www.readbyqxmd.com/read/28439784/practical-calculation-method-to-estimate-the-absolute-boron-concentration-in-tissues-using-18-f-fbpa-pet
#15
Tadashi Watabe, Kohei Hanaoka, Sadahiro Naka, Yasukazu Kanai, Hayato Ikeda, Masanao Aoki, Eku Shimosegawa, Mitsunori Kirihata, Jun Hatazawa
PURPOSE: The purpose of this study was to establish a practical method to estimate the absolute boron concentrations in the tissues based on the standardized uptake values (SUVs) after administration of 4-borono-phenylalanine (BPA) using 4-borono-2-(18)F-fluoro-phenylalanine ((18)F-FBPA) PET. METHODS: Rat xenograft models of C6 glioma (n = 7, body weight 241 ± 28.0 g) were used for the study. PET was performed 60 min after intravenous injection of (18)F-FBPA (30...
April 24, 2017: Annals of Nuclear Medicine
https://www.readbyqxmd.com/read/28438155/the-malaria-testing-and-treatment-landscape-in-the-southern-lao-people-s-democratic-republic-pdr
#16
Saysana Phanalasy
BACKGROUND: In the context of national and regional goals to eliminate malaria by 2030, the Center for Malaria Parasitology and Entomology in the Lao PDR is implementing strategies to ensure all malaria cases are detected and appropriately treated with first-line artemisinin combination therapy, artemether-lumefantrine (AL). Timely and relevant evidence to inform policies and strategies is needed to ensure the most effective and efficient use of resources, and to accelerate progress towards elimination goals...
April 25, 2017: Malaria Journal
https://www.readbyqxmd.com/read/28437768/glomeromycota-communities-survive-extreme-levels-of-metal-toxicity-in-an-orphan-mining-site
#17
I Sánchez-Castro, V Gianinazzi-Pearson, J C Cleyet-Marel, E Baudoin, D van Tuinen
Abandoned tailing basins and waste heaps of orphan mining sites are of great concern since extreme metal contamination makes soil improper for any human activity and is a permanent threat for nearby surroundings. Although spontaneous revegetation can occur, the process is slow or unsuccessful and rhizostabilisation strategies to reduce dispersal of contaminated dust represent an option to rehabilitate such sites. This requires selection of plants tolerant to such conditions, and optimization of their fitness and growth...
April 21, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28437164/factors-affecting-the-levels-of-heavy-metals-in-juices-processed-with-filter-aids
#18
Zhengfang Wang, Lauren S Jackson, Joseph E Jablonski
This study investigated factors that may contribute to the presence of arsenic and other heavy metals in apple and grape juices processed with filter aids. Different types and grades of filter aids were analyzed for arsenic, lead, and cadmium with inductively coupled plasma-tandem mass spectrometry. Potential factors affecting the transfer of heavy metals to juices during filtration treatments were evaluated. Effects of washing treatments on removal of heavy metals from filter aids were also determined. Results showed that diatomaceous earth (DE) generally contained a higher level of arsenic than perlite, whereas perlite had a higher lead content than DE...
April 24, 2017: Journal of Food Protection
https://www.readbyqxmd.com/read/28436643/ultrathin-in2o3-nanosheets-with-uniform-mesopores-for-highly-sensitive-nitric-oxide-detection
#19
Xue Wang, Juan Su, Hui Chen, Guo-Dong Li, Zhifang Shi, Haifeng Zou, Xiaoxin Zou
Nitric oxide (NOx, including NO and NO2) is one of the most dangerous environmental toxins and pollutants, mainly origins from vehicle exhaust and industrial emission. The development of sensitive NOx gas sensors is quite urgent for human health and environmental friendly. Up to now, it still remains a great challenge to develop NOx gas sensor, which can satisfy multiple application demands for sensing performance (such as high response, low detection temperature and limit). In this work, ultrathin In2O3 nanosheets with uniform mesopores were successfully synthesized through a facile two-step synthetic method...
April 24, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28435191/occurrence-of-multidrug-resistant-escherichia-coli-in-groundwater-of-brij-region-uttar-pradesh-and-its-public-health-implications
#20
Barkha Sharma, Parul, A K Verma, Udit Jain, Janaradan K Yadav, Ravneet Singh, Raghvendra Mishra
AIM: The study evaluates the microbial as well as physicochemical pollution of groundwater of Brij region of Uttar Pradesh, a major tourist destination in the country along with estimating the drug resistance evident in the isolated Escherichia coli. MATERIALS AND METHODS: A total of 60 samples of groundwater were collected from six different sites and assessed for physicochemical (pH, color, taste, turbidity, total dissolved solids [TDS], total hardness [TH], chlorides, fluorides, nitrates, and iron) and microbiological parameters (standard plate count [SPC], most probable number test [MPN], E...
March 2017: Veterinary World
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