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Uzochukwu C Ugochukwu, Alfred Ochonogor, Chika M Jidere, Chizoba Agu, Frida Nkoloagu, John Ewoh, Virginia U Okwu-Delunzu
In this study, the human and livestock (cattle) health risks of exposure to polycyclic aromatic hydrocarbons (PAHs) in a wetland of Obuaku, Abia State Nigeria contaminated by hydrocarbon spill due to incidents of hydrocarbon theft and pipeline vandalization were assessed. Gas chromatography-flame ionization detector and gas chromatography-mass spectrometry were employed in analyzing the TPH and PAHs respectively. The contaminated soil was delineated into sub-locations AOC-1, AOC-2, AOC-3, AOC-4, AOC-5 and AOC-6 to reflect the discrete patches (areas) of the contaminated site and for effective planning of remedial actions...
March 13, 2018: Environment International
Davy Guillarme, Vincent Desfontaine, Sabine Heinisch, Jean-Luc Veuthey
Mass spectrometry (MS) is considered today as one of the most popular detection methods, due to its high selectivity and sensitivity. In particular, this detector has become the gold standard for the analysis of complex mixtures such as biological samples. The first successful SFC-MS hyphenation was reported in the 80's, and since then, several ionization sources, mass analyzers and interfacing technologies have been combined. Due to the specific physicochemical properties and compressibility of the SFC mobile phase, directing the column effluent into the ionization source is more challenging than in LC...
March 7, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Samuel Mesihää, Ilpo Rasanen, Ilkka Ojanperä
Gas chromatography (GC) hyphenated with nitrogen chemiluminescence detection (NCD) and quadrupole time-of-flight mass spectrometry (QTOFMS) was applied for the first time to the quantitative analysis of new psychoactive substances (NPS) in urine, based on the N-equimolar response of NCD. A method was developed and validated to estimate the concentrations of three metabolites of the common stimulant NPS α-pyrrolidinovalerophenone (α-PVP) in spiked urine samples, simulating an analysis having no authentic reference standards for the metabolites and using the parent drug instead for quantitative calibration...
February 27, 2018: Forensic Science International
Siwapon Srisonphan
Advanced surface engineering aims to produce surfaces with well-controlled wettabilities; however, precise control over water imbibition and liquid spreading on patterned surfaces remains a challenge. Nonthermal atmospheric plasma (NAP) treatment can dramatically change wettability; however, for coated biological objects, such as seeds, plasma interaction is not entirely understood. Herein, we employed atmospheric hybrid cold plasma (HCP) to elucidate how NAP fundamentally interacts with seed surfaces. We show that nonthermal atmospheric plasma can control water imbibition (WI) and liquid spreading on seeds...
March 16, 2018: ACS Applied Materials & Interfaces
Bartolomeo Lorenzati, Riccardo Cristofori, Andrea Landi, Enrico Ruffini, Domenico Novero, Giuseppe Lauria, Bruno M Tartaglino, Alberto Oliaro, Luca Scaglione, Elio Rolfo
No abstract text is available yet for this article.
March 15, 2018: Panminerva Medica
David Bonnel, Raphaël Legouffe, André H Eriksson, Rasmus W Mortensen, Fabien Pamelard, Jonathan Stauber, Kim T Nielsen
Generation of skin distribution profiles and reliable determination of drug molecule concentration in the target region are crucial during the development process of topical products for treatment of skin diseases like psoriasis and atopic dermatitis. Imaging techniques like mass spectrometric imaging (MSI) offer sufficient spatial resolution to generate meaningful distribution profiles of a drug molecule across a skin section. In this study, we use matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to generate quantitative skin distribution profiles based on tissue extinction coefficient (TEC) determinations of four different molecules in cross sections of human skin explants after topical administration...
March 15, 2018: Analytical and Bioanalytical Chemistry
Xiaowen Sun, Lei Deng, You Lu
Microvessels promote proliferation of tumor cells by delivering oxygen and nutrients, but rapid growth of tumors results in unmet demands for oxygen and nutrients, thereby creating a hypoxia microenvironment. Under hypoxic conditions, vascular endothelial cells (ECs) initiate the formation of immature and abnormal microvasculature. This results in leakage and tortuosity that facilitates tumor cell invasion, metastasis and resistance to cytotoxic treatment. Radiotherapy (RT) is a vital tumor treatment modality...
February 2018: Chinese Journal of Cancer Research, Chung-kuo Yen Cheng Yen Chiu
A C M Veloo, H Jean-Pierre, U S Justesen, T Morris, E Urban, I Wybo, M Kostrzewa, A W Friedrich
Within the ENRIA project, several 'expertise laboratories' collaborated in order to optimize the identification of clinical anaerobic isolates by using a widely available platform, the Biotyper Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). Main Spectral Profiles (MSPs) of well characterized anaerobic strains were added to one of the latest updates of the Biotyper database db6903; (V6 database) for common use. MSPs of anaerobic strains nominated for addition to the Biotyper database are included in this validation...
March 12, 2018: Anaerobe
Sarah Caughlin, Shikhar Maheshwari, Yuksel Agca, Cansu Agca, Aaron J Harris, Kristina Jurcic, Ken K-C Yeung, David F Cechetto, Shawn N Whitehead
BACKGROUND: Accumulation of simple gangliosides GM2 and GM3, and gangliosides with longer long-chain bases (d20:1) have been linked to toxicity and the pathogenesis of Alzheimer's disease (AD). Conversely, complex gangliosides, such as GM1, have been shown to be neuroprotective. Recent evidence using matrix-assisted laser desorption ionization imaging mass spectrometry (MALDI-IMS) has demonstrated that a-series gangliosides are differentially altered during normal aging, yet it remains unclear how simple species are shifting relative to complex gangliosides in the prodromal stages of AD...
March 12, 2018: Biochimica et Biophysica Acta
Zhou Hong, Juan Li, Sangita Biswas, Cheng-Shuai Jiang, Yu Huang, Tao Sun, Yang Niu, Jian-Qiang Yu, Wei-Qi Li, Yao Yao
Tamarix ramosissima is a traditional Chinese herbal medicine used for rheumatoid arthritis (RA) treatment in Northwest China. Chemical investigation of EtOH/H2O extracts of T. ramosissima led to the discovery of a new flavonol, ramosissimin (1), together with the known flavonoids compounds quercetin (2), quercetin-3'4'-dimethylether (3) and kaempferol (4). By means of high resolution electrospray ionization mass spectroscopy (HRESIMS) and 1D and 2D-NMR experiments, and after comparison with literature data, the structures of the compounds were determined...
March 5, 2018: Die Pharmazie
Shuai Zhang, Burkhard Militzer, Lorin X Benedict, François Soubiran, Philip A Sterne, Kevin P Driver
Carbon-hydrogen plasmas and hydrocarbon materials are of broad interest to laser shock experimentalists, high energy density physicists, and astrophysicists. Accurate equations of state (EOSs) of hydrocarbons are valuable for various studies from inertial confinement fusion to planetary science. By combining path integral Monte Carlo (PIMC) results at high temperatures and density functional theory molecular dynamics results at lower temperatures, we compute the EOSs for hydrocarbons from simulations performed at 1473 separate (ρ, T)-points distributed over a range of compositions...
March 14, 2018: Journal of Chemical Physics
Benjamin G Janesko, Emil Proynov, Giovanni Scalmani, Michael J Frisch
Rung 3.5 functionals are a new class of approximations for density functional theory. They provide a flexible intermediate between exact (Hartree-Fock, HF) exchange and semilocal approximations for exchange. Existing Rung 3.5 functionals inherit semilocal functionals' limitations in atomic cores and density tails. Here we address those limitations using range-separated admixture of HF exchange. We present three new functionals. LRC-ωΠLDA combines long-range HF exchange with short-range Rung 3.5 ΠLDA exchange...
March 14, 2018: Journal of Chemical Physics
Sebastian Trippel, Joss Wiese, Terry Mullins, Jochen Küpper
Strong quasi-adiabatic laser alignment of the indole-water-dimer clusters, an amino-acid chromophore bound to a single water molecule through a hydrogen bond, was experimentally realized. The alignment was visualized through ion and electron imaging following strong-field ionization. Molecular-frame photoelectron angular distributions showed a clear suppression of the electron yield in the plane of the ionizing laser's polarization, which was analyzed as strong alignment of the molecular cluster with ⟨cos2 θ2D ⟩ ≥ 0...
March 14, 2018: Journal of Chemical Physics
V Moreno, J Bach, M Zarroca, Ll Font, C Roqué, R Linares
Radon levels in the soil and groundwater in the North Maladeta Fault area (located in the Aran Valley sector, Central Pyrenees) are analysed from both geological and radiation protection perspectives. This area is characterized by the presence of two important normal faults: the North Maladeta fault (NMF) and the Tredós Fault (TF). Two primary aspects make this study interesting: (i) the NMF shows geomorphic evidence of neotectonic activity and (ii) the presence of a thermal spa, Banhs de Tredós, which exploits one of the several natural springs of the area and needs to be evaluated for radiation dosing from radon according to the European regulation on basic safety standards for protection against ionizing radiation...
March 12, 2018: Journal of Environmental Radioactivity
Thanh D Do, Joseph F Ellis, Elizabeth K Neumann, Troy J Comi, Emily G Tillmaand, Ashley E Lenhart, Stanislav S Rubakhin, Jonathan Sweedler
The mammalian dorsal root ganglia (DRG) are located on the dorsal roots of the spinal nerves and contain cell bodies of primary sensory neurons. DRG cells have been classified into subpopulations based on their size, morphology, intracellular markers, response to stimuli, and neuropeptides. To understand the connections between DRG chemical heterogeneity and cellular function, we performed optically guided, high-throughput single cell profiling using sequential matrix-assisted laser desorption/ionization mass spectrometry (MS) to detect lipids, peptides, and several proteins in individual DRG cells...
March 15, 2018: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
Lu Hu, Wuchao Zhao, Jianghua He, Yuetao Zhang
This work reveals the silyl ketene acetal (SKA)/B(C₆F₅)₃ Lewis pair-catalyzed room-temperature group transfer polymerization (GTP) of polar acrylic monomers, including methyl linear methacrylate (MMA), and the biorenewable cyclic monomers γ-methyl-α-methylene-γ-butyrolactone (MMBL) and α-methylene-γ-butyrolactone (MBL) as well. The in situ NMR monitored reaction of SKA with B(C₆F₅)₃ indicated the formation of Frustrated Lewis Pairs (FLPs), although it is sluggish for MMA polymerization, such a FLP system exhibits highly activity and living GTP of MMBL and MBL...
March 15, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Jun-Hwan Park, Hoi-Seon Lee
The insecticidal toxicities of essential oils and other active components extracted from Eucalyptus dives leaves (as well as structural analogues) were studied against stored-product insects, Plodia interpunctella and Tribolium castaneum. 3-Carvomenthenone was purified from E. dives oil, and the structures were elucidated by electron ionization mass spectra,1 H-nuclear magnetic resonance (NMR),13 C-NMR, heteronuclear multiple quantum coherence,1 H-1 H correlation spectroscopy, and distortionless enhancement by polarization transfer NMR...
March 15, 2018: Journal of Food Protection
Asmaa Y Elsary, Alkassem A Elgameel, Wael S Mohammed, Osman M Zaki, Shaimaa A Taha
To assess the prevalence of hypocalcemia in outpatient clinic neonates and its relation to vitamin D and calcium supplementation.  Methods: This cross-sectional analytical study was conducted at the University Teaching Hospital from May to October 2016. Data were collected from 100 neonates by interviewing mothers using a structured questionnaire; which included socio-demographic information, maternal and neonatal history; in addition to investigations of serum calcium total and ionized and serum vitamin D level...
March 2018: Saudi Medical Journal
Ajay Kumar, Sumit Sharma, Rohit Mehra, Saurabh Narang, Rosaline Mishra
Background The inhalation doses resulting from the exposure to radon, thoron, and their progeny are important quantities in estimating the radiation risk for epidemiological studies as the average global annual effective dose due to radon and its progeny is 1.3 mSv as compared to that of 2.4 mSv due to all other natural sources of ionizing radiation. Objectives The annual inhalation dose has been assessed with an aim of investigating the health risk to the inhabitants of the studied region. Methods Time integrated deposition based222 Rn/220 Rn sensors have been used to measure concentrations in 146 dwellings of Udhampur district, Jammu and Kashmir...
March 15, 2018: International Journal of Occupational and Environmental Health
Zhaoxiang Liu, Jinping Yao, Jinming Chen, Bo Xu, Wei Chu, Ya Cheng
The generation of laserlike narrow bandwidth emissions from nitrogen molecular ions (N_{2}^{+}) generated in intense near- and mid infrared femtosecond laser fields has aroused much interest because of the mysterious physics underlying such a phenomenon. Here, we perform a pump-probe measurement on the nonlinear interaction of rotational quantum wave packets of N_{2}^{+} generated in midinfrared (e.g., at a wavelength centered at 1580 nm) femtosecond laser fields with an ultrashort probe pulse whose broad spectrum overlaps both P- and R-branch rotational transition lines between the electronic states N_{2}^{+}(B^{2}Σ_{u}^{+},v^{'}=0) and N_{2}^{+}(X^{2}Σ_{g}^{+},v=0)...
February 23, 2018: Physical Review Letters
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