bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of Listeria spp. Using ACTERO Listeria Enrichment Media
Authors: Claveau David , Olishevskyy Sergiy , Giuffre Michael , Martinez Gabriela 
Published: July 2014

Abstract
ACTERO™ Listeria Enrichment Media (ACTERO Listeria) is a selective medium developed for a single-step recovery and enrichment of Listeria spp. from environmental samples. Robustness testing of the ACTERO Listeria medium demonstrated good performance when minor changes were introduced to the incubation temperature and time. All 54 Listeria strains tested, representing the most frequently isolated Listeria species from food (L. monocytogenes, L. ivanovii, L. seeligeri, L. welshimeri, and L. grayi), were successfully enriched in ACTERO Listeria. None of the 30 nontarget strains tested in the exclusivity study was recovered after incubation in ACTERO Listeria. Recovery of Listeria was consistent across three independently produced lots of the ACTERO Listeria, and the prepared medium was stable for 45 days when stored at 4°C in the dark. Matrix studies performed with environmental sponge samples from plastic and stainless steel surfaces demonstrated similar recovery of Listeria spp. in a single-step enrichment using ACTERO Listeria from plastic, and significantly better recovery from stainless steel surfaces when compared to the U.S. Department of Agriculture-Food Safety and Inspection Service reference method. The results of this study prove that ACTERO Listeria Enrichment Media can be effectively used in replacement of the two-step enrichment suggested by the reference method without affecting the recovery of Listeria spp. from environmental samples.
Determination of Folate in Infant Formula and Adult/Pediatric Nutritional Formula by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry: First Action 2013.13
Authors: Meisser-Redeuil Karine , Bénet Sylvie , Gimenez Catherine , Campos-Giménez Esther , Nelson Maria 
Published: July 2014

Abstract
A UHPLC-MS/MS method for the determination of folate (vitamin B9) in infant formula and adult/pediatric nutritional formula was assessed for compliance with standard method performance requirements set forth by the AOAC INTERNATIONAL Stakeholder Panel for Infant Formula and Adult Nutritionals (SPIFAN). A single-laboratory validation (SLV) study was conducted as the first step in the process to validate the method. In the study, 12 matrixes, representing the range of infant and adult nutritional products, were evaluated for folate [the sum of supplemental folic acid plus 5-methyl tetrahydrofolic acid (5-Me THF)]. Method response was linear in the range of 1.0–900 ng/mL, corresponding to 0.33–300 μg/100 g in reconstituted sample. LOD for folic acid and 5-Me THF, expressed in reconstituted product, were 0.10 μg/100 g and 0.05 μg/100 g, respectively, and LOQ were 0.33 μg/100 g and 0.10 μg/100 g, respectively. Repeatability was &lt;5.3% and intermediate precision was &lt;5.5%. Recovery rates of spiking at 50 and 100% of target values in nonfortified products were within 90–110%. Evaluation of trueness was performed on Certified Reference Material (SRM 1849 Infant/Adult Nutritional Formula) and gave 96.4% of theoretical value. Based on the results of the SLV, the method meets the SPIFAN requirements for AOAC First Action status for the determination of folates in infant formula and adult/pediatric nutritional formula.
Multiresidue Analysis of Insecticides and Other Selected Environmental Contaminants in Poultry Manure by Gas Chromatography/Mass Spectrometry
Authors: Aznar Ramón , Albero Beatriz , Sánchez-Brunete Consuelo , Miguel Esther , Tadeo José L 
Published: July 2014

Abstract
An analytical method was developed for the simultaneous determination in poultry manure of 41 organic contaminants belonging to different chemical classes: pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and polybrominated diphenyl ethers. Poultry manure was extracted with a modified QuEChERS method, and the extracts were analyzed by isotope dilution GC/MS. Recovery of these contaminants from samples spiked at levels ranging from 25 to 100 ng/g was satisfactory for all the compounds. The developed procedure provided LODs from 0.8 to 9.6 ng/g. The analysis of poultry manure samples collected on different farms confirmed the presence of some of the studied contaminants. Pyrethroids and polycyclic aromatic hydrocarbons were the main contaminants detected. DDT and its metabolite DDE were also found but at relatively low concentrations.
Pesticide Multiresidue Determination in Rice Paddy Water by Gas Chromatography Coupled with Triple Quadrupole Mass Spectrometry
Authors: Pereira Mateus B , Facco Janice F , Zemolin Gabriela M , Martins Manoel L , Prestes Osmar D , Zanella Renato , Adaime Martha B 
Published: July 2014

Abstract
Pollution of water sources by pesticides is a result of intensive use of these compounds, and the establishment of analytical methods for monitoring programs is very important. This paper presents a method for the determination of multiclass pesticide residues in rice paddy water based on SPE and GC/MS/MS. The validation results were satisfactory. All compounds showed adequate linearity (r2 ≥ 0.99), and analysis by GC/MS/MS with a triple quadrupole mass spectrometer gave high selectivity and sensitivity. With the proposed SPE step an LOD of 0.06 μg/L was achieved. Recoveries from blank samples spiked at 0.2, 04, and 0.8 μg/L were between 70 and 120% with RSD &lt;20% for most analyzed compounds, despite their different chemical nature, indicating good accuracy and precision. The proposed method is efficient for pesticide residue determination, including some metabolites, and gave good performance when applied to real samples.
Electro-Oxidation and Determination of Benomyl by Square-Wave Adsorptive Stripping Voltammetry
Authors: Sarıgül Tuba , İnam Recai , Demir Ersin , Aboul-Enein Hassan Y 
Published: July 2014

Abstract
The electro-oxidation of the benomyl fungicide was studied by square-wave adsorptive stripping voltammetry. The voltammetric current at a glassy carbon electrode was acquired within the pH range 1.0–10.0. The quantitation was performed using the peak generated at +1144 mV by scanning the potential from +0.00 to +1600 mV (versus an Ag/AgCl reference electrode, 3 M NaCl). Accumulation potential = 0.0 mV, accumulation time = 45 s, frequency = 75 Hz, pulse amplitude = –60 mV, and staircase step potential = 7 mV were used as square-wave parameters. The peak current versus concentrations plot were rectilinear over the range from 0.081 to 1.496 μg/mL with an LOD of 0.024 μg/mL. Mean recovery was 99.0% (0.198 ± 0.011 μg/mL), which was very close to the benomyl content spiked into river water (0.20 μg/mL). The method was efficiently applied for benomyl determination in the pesticide formulation Minelate 50WG®, and the average determined content of 49.8 ± 0.16 (n = 5) was consistent with the 50% benomyl (w/w) quoted by the manufacturer. The benomyl voltammograms recorded between days exhibited a negligible degradation into carbendazim metabolite, and therefore all results were given as the total benomyl concentration. The high recoveries and low RSD gave evidence of good accuracy and precision.
Targeting Cancer Stem Cell Plasticity Through Modulation of Epidermal Growth Factor and Insulin-Like Growth Factor Receptor Signaling in Head and Neck Squamous Cell Cancer
Authors: Leong Hui Sun , Chong Fui Teen , Sew Pui Hoon , Lau Dawn P. , Wong Bernice H. , Teh Bin-Tean , Tan Daniel S.W. , Iyer N. Gopalakrishna 
Published: July 2014

Abstract

Emerging data suggest that cancer stem cells (CSCs) exist in equilibrium with differentiated cells and that stochastic transitions between these states can account for tumor heterogeneity and drug resistance. The aim of this study was to establish an in vitro system that recapitulates stem cell plasticity in head and neck squamous cell cancers (HNSCCs) and identify the factors that play a role in the maintenance and repopulation of CSCs. Tumor spheres were established using patient-derived cell lines via anchorage-independent cell culture techniques. These tumor spheres were found to have higher aldehyde dehydrogenase (ALD) cell fractions and increased expression of Kruppel-like factor 4, SRY (sex determining region Y)-box 2, and Nanog and were resistant to γ-radiation, 5-fluorouracil, cisplatin, and etoposide treatment compared with monolayer culture cells. Monolayer cultures were subject to single cell cloning to generate clones with high and low ALD fractions. ALDHigh clones showed higher expression of stem cell and epithelial-mesenchymal transition markers compared with ALDLow clones. ALD fractions, representing stem cell fractions, fluctuated with serial passaging, equilibrating at a level specific to each cell line, and could be augmented by the addition of epidermal growth factor (EGF) and/or insulin. ALDHigh clones showed increased EGF receptor (EGFR) and insulin-like growth factor-1 receptor (IGF-1R) phosphorylation, with increased activation of downstream pathways compared with ALDLow clones. Importantly, blocking these pathways using specific inhibitors against EGFR and IGF-1R reduced stem cell fractions drastically. Taken together, these results show that HNSCC CSCs exhibit plasticity, with the maintenance of the stem cell fraction dependent on the EGFR and IGF-1R pathways and potentially amenable to targeted therapeutics.
Seafloor basalt alteration and chemical change in the ultra thinly sedimented South Pacific
Authors: Zhang Guo‐Liang , Smith‐Duque Christopher 
Published: July 2014

AbstractDetermining the relationship between ocean floor basalt alteration and sedimentation is fundamental to understanding how oceanic crust evolves with time. Ocean floor basalts recovered at IODP Sites U1365 (∼100 Ma) and U1368 (∼13.5 Ma) in the South Pacific have been subjected to remarkably low sedimentation rates (0.71 and 1.1 m/Myr−1, respectively). We report detailed petrographic and geochemical analysis of basalt cores from these sites in order to investigate what impact sediment insulation has on seafloor alteration beyond 10–15 Myr of ocean crust formation. Both sites exhibit low‐temperature (<150°C) alteration (e.g., iron‐hydroxides, carbonate, and quartz) within a predominantly oxidative regime, albeit with markedly different alteration styles and intensity. Alteration at Site U1365, which is predominantly composed of sheet flows, occurs mainly near sheet flow boundaries and fractures. In contrast, Site U1368 comprises interlayered pillows and thin sheet flows that have been subjected to relatively even levels of alteration. Variation of alteration style and intensity between Sites U1365 and U1368 appear closely tied to lithology and crustal structure. Although alteration‐induced elemental changes at both sites are similar in, e.g., increasing K, Rb, U, Ba, and Fe3+ and decreasing Fe2+, Ca, and Ni, they show distinct differences in Th, which is significantly decreased at Site U1365 but relatively constant at Site U1368. At both sites enrichment of LREEs relative to HREEs is ascribed to alteration. The greater vein abundance and notably higher Fe3+/TiO2, K2O/TiO2, LOI/TiO2, and Rb/TiO2 ratios of representative samples at Site U1365 compared to Site U1368 are attributed to increased alteration intensity. This is mirrored by greater overall chemical change (Fe2O3, FeO, CaO, K2O, Li, Rb, Pb, and U) observed at Site U1365 than those of Site U1368 and other DSDP/ODP sites between 6 and 46 Ma. Since both Sites U1365 and U1368 endured only minimal sedimentation, we attribute the differences in overall chemical change across the two sites to duration of exposure to seawater.
Calcium sulfate veins characterized by ChemCam/Curiosity at Gale crater, Mars
Authors: Nachon M. , Clegg S. M. , Mangold N. , Schröder S. , Kah L. C. , Dromart G. , Ollila A. , Johnson J. R. , Oehler D. Z. , Bridges J. C. , Le Mouélic S. , Forni O. , Wiens R.C. , Anderson R. B. , Blaney D. L. , Bell J.F. , Clark B. , Cousin A. , Dyar M. D. , Ehlmann B. , Fabre C. , Gasnault O. , Grotzinger J. , Lasue J. , Lewin E. , Léveillé R. , McLennan S. , Maurice S. , Meslin P.‐Y. , Rapin W. , Rice M. , Squyres S. W. , Stack K. , Sumner D. Y. , Vaniman D. , Wellington D. 
Published: July 2014

AbstractThe Curiosity rover has analyzed abundant light‐toned fracture‐fill material within the Yellowknife Bay sedimentary deposits. The ChemCam instrument, coupled with Mastcam and ChemCam/Remote Micro Imager images, was able to demonstrate that these fracture fills consist of calcium sulfate veins, many of which appear to be hydrated at a level expected for gypsum and bassanite. Anhydrite is locally present and is found in a location characterized by a nodular texture. An intricate assemblage of veins crosses the sediments, which were likely formed by precipitation from fluids circulating through fractures. The presence of veins throughout the entire ~5 m thick Yellowknife Bay sediments suggests that this process occurred well after sedimentation and cementation/lithification of those sediments. The sulfur‐rich fluids may have originated in previously precipitated sulfate‐rich layers, either before the deposition of the Sheepbed mudstones or from unrelated units such as the sulfates at the base of Mount Sharp. The occurrence of these veins after the episodes of deposition of fluvial sediments at the surface suggests persistent aqueous activity in relatively nonacidic conditions.
Characterization of flow parameters and evidence of pore clogging during limestone dissolution experiments
Authors: Luquot L. , Roetting T. S. , Carrera J. 
Published: July 2014

AbstractRock dissolution induces changes in texture (porosity, pore‐size distribution, or tortuosity) which modify multiphase flow and transport properties (permeability, diffusion coefficient, retention curve). Limestone dissolution will occur during CO2 storage or acid injection for well stimulation. Therefore, characterizing those changes is essential for understanding flow and transport during and after the CO2 injection because they can affect the storage capacity, injectivity, and trapping mechanisms. Yet, few published studies evaluate the changes of hydrodynamic properties due to fluid‐rock interactions. We report seven dissolution experiments performed on four limestone samples by injecting water with pH ranging from 3.5 to 5.0. Sample porosity, diffusion coefficient, and pore‐size distribution were measured before and after each rock attack, which was repeated twice on three of the samples. Permeability was monitored continuously and chemical samples were taken to evaluate calcite dissolution. We find that overall porosity increases over time as expected. But the increase is nonuniform along the sample. At the samples inlets, large pores increase significantly while small pores remain unchanged, which is consistent with wormhole initiation. However, the size of largest pores is reduced at the outlet, which we attribute to clogging by particles dragged from the inlet. As a result, the overall permeability is reduced. Particle dragging is unlikely during supercritical CO2 storage because head gradients are small, but may be expected in the case of dissolved CO2 injection or during well stimulation by acid injection. Our results imply that dissolution is highly localized, which will result in a significant increase in capillary trapping.
Approximately 1.78 Ga mafic dykes in the Lüliang Complex, North China Craton: Zircon ages and Lu‐Hf isotopes, geochemistry, and implications
Authors: Wang Xi , Zhu Wenbin , Luo Meng , Ren Xingmin , Cui Xiang 
Published: July 2014

AbstractMafic dyke swarms are excellent time markers and paleostress indicators. Numerous late Paleoproterozoic mafic dykes are exposed throughout the Trans‐North China Orogen (TNCO). Most of these dykes trend NW‐SE or NNW‐SSE, nearly parallel to the orogen, while a series of E‐W trending mafic dykes are restricted in the Lüliang and southern Taihang areas in the central segment of the TNCO. These dykes were mostly considered to be linked with breakup of the supercontinent Columbia previously. In this study, 16 mafic dykes were investigated in the Lüliang Complex. Zircon LA‐ICP‐MS dating of four samples yields magmatic crystallization ages of 1.78–1.79 Ga. These dykes belong to the tholeiite series and consist of basalt, basaltic andesite, and andesite. They are enriched in LREE and LILE and depleted in HFSE, and have negative zircon εHf(t) values of −1.7 to −12.2. The E‐W trending mafic dykes show similar geochemical and isotopic features compared to the NW‐SE trending dykes in other complexes. They were most likely originated from a lithospheric mantle metasomatized by subduction‐related fluids and later emplaced along extensional fractures in a postcollisional setting. NW‐SE trending fractures were formed due to gravitational collapse and thinning of the lithosphere. E‐W trending fractures in the central segment of the orogen constitute a transverse accommodation belt to equilibrate the different amounts of extension between the northern and southern TNCO. The impact of the postorogenic extension might have continued to approximately 1680 Ma as evidenced by the presence of abundant approximately 1750–1680 Ma anorthosite‐gabbro‐mangerite‐rapakivi granite suites (AMCG‐like) occurring in the northern NCC.
Multiphase OH oxidation kinetics of organic aerosol: The role of particle phase state and relative humidity
Authors: Slade Jonathan H. , Knopf Daniel A. 
Published: July 2014

AbstractOrganic aerosol can exhibit different phase states in response to changes in relative humidity (RH), thereby influencing heterogeneous reaction rates with trace gas species. OH radical uptake by laboratory‐generated levoglucosan and methyl‐nitrocatechol particles, serving as surrogates for biomass burning aerosol, is determined as a function of RH. Increasing RH lowers the viscosity of amorphous levoglucosan aerosol particles enabling enhanced OH uptake. Conversely, OH uptake by methyl‐nitrocatechol aerosol particles is suppressed at higher RH as a result of competitive coadsorption of H2O that occupies reactive sites. This is shown to have substantial impacts on organic aerosol lifetimes with respect to OH oxidation. The results emphasize the importance of organic aerosol phase state to accurately describe the multiphase chemical kinetics and thus chemical aging process in atmospheric models to better represent the evolution of organic aerosol and its role in air quality and climate.
Upper atmosphere cooling over the past 33 years
Authors: Ogawa Y. , Motoba T. , Buchert S. C. , Häggström I. , Nozawa S. 
Published: July 2014

AbstractTheoretical models and observations have suggested that the increasing greenhouse gas concentration in the troposphere causes the upper atmosphere to cool and contract. However, our understanding of the long‐term trends in the upper atmosphere is still quite incomplete, due to a limited amount of available and well‐calibrated data. The European Incoherent Scatter radar has gathered data in the polar ionosphere above Tromsø for over 33 years. Using this long‐term data set, we have estimated the first significant trends of ion temperature at altitudes between 200 and 450 km. The estimated trends indicate a cooling of 10–15 K/decade near the F region peak (220–380 km altitude), whereas above 400 km the trend is nearly zero or even warming. The height profiles of the observed trends are close to those predicted by recent atmospheric general circulation models. Our results are the first quantitative confirmation of the simulations and of the qualitative expectations.
A posteriori adjustment of near‐term climate predictions: Accounting for the drift dependence on the initial conditions
Authors: Fučkar Neven S. , Volpi Danila , Guemas Virginie , Doblas‐Reyes Francisco J. 
Published: July 2014

AbstractClimate predictions initialized from an observationally based state (OBS) drift toward the state of the unconstrained model, which makes the use of a posteriori correction methods essential to disentangle the climate signal of interest from the model bias. We propose that applying a linear regression of the predictions and corresponding OBS on the OBS initial conditions (IC), and substituting the latter for the former, offers an effective method for bias correction. The impact of this new method is examined on monthly means of large‐scale sea surface temperature indices and the Northern Hemisphere sea ice extent in EC‐Earth2.3 predictions. This postprocessing adjustment through a linear regression on the averaged OBS over the first forecast month as a temporarily smoothed proxy for OBS IC shows a reduction of model error with respect to the two established bias correction methods. Improvements are seen for at least two seasons and for some variables up to 5 years.
Investigation of the seasonal and local time variations of the high‐altitude sporadic Na layer (Nas) formation and the associated midlatitude descending E layer (Es) in lower E region
Authors: Yuan T. , Wang Jihong , Cai Xuguang , Sojka J. , Rice D. , Oberheide J. , Criddle N. 
Published: July 2014

AbstractRecent studies have suggested that the major reservoir for the sporadic sodium layer (Nas) above 95 km in altitude is likely the sodium ion (Na+) within the sporadic E layer (Es) in the lower E region. However, theoretical and laboratory works have demonstrated that the metal ion's neutralization process is quite difficult above 100 km, while intensive neutral metal layers are consistently observed in the lower E region between 100 km and 125 km. In this paper, the multiyear observations of a Na lidar and an ionosonde at Utah State University (41.7°N, 111.8°W) and the nearby Bear Lake Observatory (41.9°N, 111.4°W) are utilized to understand their seasonal and local time variations. The comparison study between this set of the Nas and the nocturnal Nas observations in Beijing China (40.2°N, 116.1°E) reveals similar variations, but major differences are also noticed. To investigate the mechanism of these variations, the Hamburg Model of the Neutral and Ionized Atmosphere and the Climatological Tidal Model of the Thermosphere are utilized to simulate the ion vertical drift in the lower E region. The simulation shows that the lower E region is dominated by convergence of metal ions in summer, and ion diffusion prevails during winter. The tidal wind modulates the ion vertical drift speed and increases the likelihood of Es evolution at certain local times during the summer, while the tidal components of atmospheric density facilitate Nas formation by neutralizing the Na+ within the Es.
Southern Ocean velocity and geostrophic transport fields estimated by combining Jason altimetry and Argo data
Authors: Kosempa Michael , Chambers Don P. 
Published: July 2014

AbstractZonal geostrophic velocity fields above 1975 dbar have been estimated for the Southern Ocean from 2004 into 2011 based on sea surface topography observed by Jason altimetry and temperature/salinity measured by Argo autonomous floats. The velocity at 1000 dbar estimated with the method has been compared to Argo drift trajectory at the same pressure level available from the Asia Pacific Data Research Center (APDRC). The inferred velocities agree with those from the Argo drift within the estimated sampling error of the latter, but have fewer gaps in space and time. The velocity has also been integrated from depth to surface to determine the mean and time‐variable zonal geostrophic transport in the Southern Ocean between 29.5°S and 58.5°S, primarily in the South Atlantic and South Indian Ocean basins, due to limitations in coverage of Argo. Analysis shows errors can be reduced by >70% by averaging gridded results over wide areas. Zonal transport averaged over the entire Indian Ocean basin shows a significant correlation with the Antarctic Oscillation (AAO) at low frequencies: transport is higher than normal during a positive phase of the AAO, and lower during the negative phase.