The OASIS Mission

NASA Technical Reports Server (NTRS)

Adams, James H., Jr.; Barghouty, Abdulnasser F.; Binns, W. robert; Christl, Mark; Cosse, Charles B.; Guzik, T. Gregory; deNolfo, Georgia A.; Hams,Thomas; Isbert, Joachim; Israel, Martin H.;

OASIS for the Old.

ERIC Educational Resources Information Center

Franklin, Betty; Smith, Bert Kruger

This report describes Project OASIS (Older Adults Sharing Important Skills), a project designed to provide paraprofessional mental health services to nursing home residents by providing training for older adult volunteers in areas related to mental health and the elderly, supervision by OASIS staff, and consultation by staff. The background of the…

Overexpression of a modified plant thionin enhances disease resistance to citrus canker and Huanglongbing (HLB)

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB or citrus greening disease) caused by Candidatus Liberibacter asiaticus (Las) is a great threat to the United States citrus industry. There are no proven strategies to eliminate HLB disease and no cultivar has been identified with strong HLB resistance. Citrus canker is also an ec...

Endemic pathogens may interfere with HLB

USDA-ARS?s Scientific Manuscript database

Since the first citrus tree was confirmed positive for Candidatus Liberibacter asiaticus (CLas), the causal agent of Huanglongbing (HLB) in 2012, trees continue to be found in urban areas of southern California that are also positive for CLas, demonstrating a slow spread of this disease. However, C...

Multi-layer solid-phase extraction and evaporation-enrichment methods for polar organic chemicals from aqueous matrices.

PubMed

Köke, Niklas; Zahn, Daniel; Knepper, Thomas P; Frömel, Tobias

2018-03-01

Analysis of polar organic chemicals in the aquatic environment is exacerbated by the lack of suitable and widely applicable enrichment methods. In this work, we assessed the suitability of a novel combination of well-known solid-phase extraction (SPE) materials in one cartridge as well as an evaporation method and for the enrichment of 26 polar model substances (predominantly log D < 0) covering a broad range of physico-chemical properties in three different aqueous matrices. The multi-layer solid-phase extraction (mlSPE) and evaporation method were investigated for the recovery and matrix effects of the model substances and analyzed with hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS). In total, 65% of the model substances were amenable (> 10% recovery) to the mlSPE method with a mean recovery of 76% while 73% of the model substances were enriched with the evaporation method achieving a mean recovery of 78%. Target and non-target screening comparison of both methods with a frequently used reversed-phase SPE method utilizing "hydrophilic and lipophilic balanced" (HLB) material was performed. Target analysis showed that the mlSPE and evaporation method have pronounced advantages over the HLB method since the HLB material retained only 30% of the model substances. Non-target screening of a ground water sample with the investigated enrichment methods showed that the median retention time of all detected features on a HILIC system decreased in the order mlSPE (3641 features, median t R 9.7 min), evaporation (1391, 9.3 min), HLB (4414, 7.2 min), indicating a higher potential of the described methods to enrich polar analytes from water compared with HLB-SPE. Graphical abstract Schematic of the method evaluation (recovery and matrix effects) and method comparison (target and non-target analysis) of the two investigated enrichment methods for very polar chemicals in aqueousmatrices.

Develop a novel target-basis of anti-virulence strategy for controlling HLB

USDA-ARS?s Scientific Manuscript database

The goal of this CRB-funded research project is to develop target-based anti-virulence therapeutics for Huanglongbing (HLB). Since the first report of citrus HLB in Florida in 2005, the disease is now looming large in Texas and California. In Florida, citrus growers are encountering severe decline o...

42 CFR 484.20 - Condition of participation: Reporting OASIS information.

Code of Federal Regulations, 2014 CFR

2014-10-01

... layout, edit specifications, and data dictionary, and that includes the required OASIS data set. [64 FR... OASIS data collected in accordance with § 484.55. (a) Standard: Encoding and transmitting OASIS data. An... beneficiary. (b) Standard: Accuracy of encoded OASIS data. The encoded OASIS data must accurately reflect the...

42 CFR 484.20 - Condition of participation: Reporting OASIS information.

Code of Federal Regulations, 2012 CFR

2012-10-01

... layout, edit specifications, and data dictionary, and that includes the required OASIS data set. [64 FR... OASIS data collected in accordance with § 484.55. (a) Standard: Encoding and transmitting OASIS data. An... beneficiary. (b) Standard: Accuracy of encoded OASIS data. The encoded OASIS data must accurately reflect the...

42 CFR 484.20 - Condition of participation: Reporting OASIS information.

Code of Federal Regulations, 2013 CFR

2013-10-01

... layout, edit specifications, and data dictionary, and that includes the required OASIS data set. [64 FR... OASIS data collected in accordance with § 484.55. (a) Standard: Encoding and transmitting OASIS data. An... beneficiary. (b) Standard: Accuracy of encoded OASIS data. The encoded OASIS data must accurately reflect the...

42 CFR 484.20 - Condition of participation: Reporting OASIS information.

Code of Federal Regulations, 2011 CFR

2011-10-01

... layout, edit specifications, and data dictionary, and that includes the required OASIS data set. [64 FR... OASIS data collected in accordance with § 484.55. (a) Standard: Encoding and transmitting OASIS data. An... beneficiary. (b) Standard: Accuracy of encoded OASIS data. The encoded OASIS data must accurately reflect the...

Orbiting Astrophysical Spectrometer in Space (OASIS)

NASA Technical Reports Server (NTRS)

Adams, James H.

2008-01-01

This viewgraph presentation reviews the OASIS mission. The contents include: 1) Introduction to Cosmic Rays; 2) How are they accelerated?; 3) OASIS Objectives; 4) 5) HEPCaT Instrument; and 6) ENTICE Instrument

OASIS modulates hypoxia pathway activity to regulate bone angiogenesis

PubMed Central

Cui, Min; Kanemoto, Soshi; Cui, Xiang; Kaneko, Masayuki; Asada, Rie; Matsuhisa, Koji; Tanimoto, Keiji; Yoshimoto, Yuki; Shukunami, Chisa; Imaizumi, Kazunori

2015-01-01

OASIS/CREB3L1, an endoplasmic reticulum (ER)-resident transcription factor, plays important roles in osteoblast differentiation. In this study, we identified new crosstalk between OASIS and the hypoxia signaling pathway, which regulates vascularization during bone development. RT-PCR and real-time PCR analyses revealed significant decreases in the expression levels of hypoxia-inducible factor-1α (HIF-1α) target genes such as vascular endothelial growth factor A (VEGFA) in OASIS-deficient (Oasis−/−) mouse embryonic fibroblasts. In coimmunoprecipitation experiments, the N-terminal fragment of OASIS (OASIS-N; activated form of OASIS) bound to HIF-1α through the bZIP domain. Luciferase assays showed that OASIS-N promoted the transcription activities of a reporter gene via a hypoxia-response element (HRE). Furthermore, the expression levels of an angiogenic factor Vegfa was decreased in Oasis−/− osteoblasts. Immunostaining and metatarsal angiogenesis assay showed retarded vascularization in bone tissue of Oasis−/− mice. These results suggest that OASIS affects the expression of HIF-1α target genes through the protein interaction with HIF-1α, and that OASIS-HIF-1α complexes may play essential roles in angiogenesis during bone development. PMID:26558437

Effect of Abscission Zone Formation on Orange ( Citrus sinensis) Fruit/Juice Quality for Trees Affected by Huanglongbing (HLB).

PubMed

Baldwin, Elizabeth; Plotto, Anne; Bai, Jinhe; Manthey, John; Zhao, Wei; Raithore, Smita; Irey, Mike

2018-03-21

Orange trees affected by huanglongbing (HLB) exhibit excessive fruit drop, and fruit loosely attached to the tree may have inferior flavor. Fruit were collected from healthy and HLB-infected ( Candidatus liberibacter asiaticus) 'Hamlin' and 'Valencia' trees. Prior to harvest, the trees were shaken, fruit that dropped collected, tree-retained fruit harvested, and all fruit juiced. For chemical analyses, sugars and acids were generally lowest in HLB dropped (HLB-D) fruit juice compared to nonshaken healthy (H), healthy retained (H-R), and healthy dropped fruit (H-D) in early season (December) but not for the late season (January) 'Hamlin' or 'Valencia' except for sugar/acid ratio. The bitter limonoids, many flavonoids, and terpenoid volatiles were generally higher in HLB juice, especially HLB-D juice, compared to the other samples. The lower sugars, higher bitter limonoids, flavonoids, and terpenoid volatiles in HLB-D fruit, loosely attached to the tree, contributed to off-flavor, as was confirmed by sensory analyses.

Entomofauna of Ziban Oasis, Biskra, Algeria

PubMed Central

Deghiche-Diab, Nassima; Porcelli, Francisco; Belhamra, Mohamed

2015-01-01

An inventory was carried out at five stations in the oasis of Ziban, an oasis that is characterized by its high-quality dates, in order to study the relationships between the oasis ecosystem and its insect fauna. Specimens were sampled using pitfall traps containing ethylene glycol as a preservative. In total, 115 arthropod species were collected during 5 months of survey. These species belonged to 61 families, 17 orders, and 4 classes (12 orders from Insecta, 3 from Arachnida, 1 from Chilopoda, and 1 from Malocostraca). The most represented insect orders were Coleoptera (44.42%), Hymenoptera (20.86%), and Lepidoptera (7.87%). Represented in the collections were phytophagous, omnivorous, and predator/parasite species. Given the large number of species collected, and the largely unknown relationships existing between the various ecological groups, this study is a first step in the description of the oasis entomofauna. PMID:25855607

Oasis dynamics change and its influence on landscape pattern on Jinta oasis in arid China from 1963a to 2010a: Integration of multi-source satellite images

NASA Astrophysics Data System (ADS)

Xie, Yuchu; Gong, Jie; Sun, Peng; Gou, Xiaohua

2014-12-01

As one of the vital research highlights of global land use and cover change, oasis change and its interaction with landscape pattern have been regarded as an important content of regional environmental change research in arid areas. Jinta oasis, a typical agricultural oasis characterized by its dramatic exploitation and use of water and land resources in Hexi corridor, northwest arid region in China, was selected as a case to study the spatiotemporal oasis change and its effects on oasis landscape pattern. Based on integration of Keyhole satellite photographs, KATE-200 photographs, Landsat MSS, TM and ETM+ images, we evaluated and analyzed the status, trend and spatial pattern change of Jinta oasis and the characteristics of landscape pattern change by a set of mathematical models and combined this information with landscape metrics and community surveys. During the period of 1963a-2010a, Jinta oasis expanded gradually with an area increase of 219.15 km2, and the conversion between oasis and desert was frequent with a state of “imbalance-balance-extreme imbalance conditions”. Moreover, most of the changes took place in the ecotone between oasis and desert and the interior of oasis due to the reclamation of abandoned land, such as Yangjingziwan and Xiba townships. Furthermore, the area, size and spatial distribution of oasis were influenced by human activities and resulted in fundamental changes of oasis landscape pattern. The fractal characteristics, dispersion degree and fragmentation of Jinta oasis decreased and the oasis landscape tended to be simple and uniform. Oasis change trajectories and its landscape pattern were mainly influenced by water resource utilization, policies (especially land policies), demographic factors, technological advancements, as well as regional economic development. We found that time series analysis of multi-source remote sensing images and the application of an oasis change model provided a useful approach to monitor oasis change

From Workbook to Web: Building an Information Literacy OASIS.

ERIC Educational Resources Information Center

Rosen, Jeff; Castro, Gina M.

2002-01-01

Describes a Web-based information literacy tutorial, OASIS (Online Advancement of Student Information Skills), developed at San Francisco State University. Discussion includes: core competencies identified; design structure and content; planning and marketing; problems and partnerships in the pilot year of OASIS; restructuring the OASIS tutorial;…

Study on the oasis corridor landscape in the arid regions based on RS and GIS methods--application of Jinta Oasis, China.

PubMed

Ma, Ming-guo; Wang, Xue-mei; Cheng, Guo-dong

2003-03-01

The study on the oasis corridor landsape is a new hotspot in the ecological environment research in the arid regions. In oasis, main corridor landscape types include river, ditch, shelterbelt and road. This paper introduces the basic ecological effects of the corridor landscape on the transporting mass and energy and obstructing desert landscape expansion and incursion. Using Geographic Information System (GIS), we have researched the corridor distribution and its spatial relationship with other landscape types in the Jinta Oasis. Based on the dynamically monitoring on the landscape pattern change of the Jinta Oasis during the latter 10 years by using Remote Sensing (RS) and GIS, the driving functions of the corridors on this change have been analyzed in detail. The analysis results showed that all kinds of corridors' characteristics can be quantified by the indexes such as length and width, ratio of perimeter and area, density and non-heterogeneity. The total corridor length of Jinta Oasis is 1838.5 km and its density is 2.1 km/km2. The corridor density of the irrigation land, forest and resident area is maximal, which shows that affection degree of the oasis corridors on them is the most. The improvement of the corridors quality is one of the important driving factors on the irrigation land and so on. The organic combination of the RS and GIS technologies and landscape research methods would be an effective means for the corridor landscape research on arid region oasis.

Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodegradation.

PubMed

Torres, Luis G; Rojas, Neftalí; Iturbe, Rosario

2004-01-01

In a surfactant assisted biodegradation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant (i.e. chemical family) affect the biodegradation process at fixed hidrophillic-lypofillic balance (HLB) values? Microcosm assessments were developed using contaminated soil, with around of 5000 mg/kg of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to get a wide range of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to get HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodegradation was measured at the beginning, and after 8 weeks, as well as the FCU/gr(soil), as a measure of microorganisms' development during the biodegradation period. A second aim of this work was to assess the use of guar gum as a biodegradation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodegradation rate. Surfactant's synergism was clearly observed. Regarding the use of guar gum, no biodegradation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg/kg, respectively. On the contrary, TPH-diesel removal was lower as the gum concentration increased. It is quite possible that guar gum was used as a microbial substrate.

OASIS: Prototyping Graphical Interfaces to Networked Information.

ERIC Educational Resources Information Center

Buckland, Michael K.; And Others

1993-01-01

Describes the latest modifications being made to OASIS, a front-end enhancement to the University of California's MELVYL online union catalog. Highlights include the X Windows interface; multiple database searching to act as an information network; Lisp implementation for flexible data representation; and OASIS commands and features to help…

Oasis: online analysis of small RNA deep sequencing data.

PubMed

Capece, Vincenzo; Garcia Vizcaino, Julio C; Vidal, Ramon; Rahman, Raza-Ur; Pena Centeno, Tonatiuh; Shomroni, Orr; Suberviola, Irantzu; Fischer, Andre; Bonn, Stefan

2015-07-01

Oasis is a web application that allows for the fast and flexible online analysis of small-RNA-seq (sRNA-seq) data. It was designed for the end user in the lab, providing an easy-to-use web frontend including video tutorials, demo data and best practice step-by-step guidelines on how to analyze sRNA-seq data. Oasis' exclusive selling points are a differential expression module that allows for the multivariate analysis of samples, a classification module for robust biomarker detection and an advanced programming interface that supports the batch submission of jobs. Both modules include the analysis of novel miRNAs, miRNA targets and functional analyses including GO and pathway enrichment. Oasis generates downloadable interactive web reports for easy visualization, exploration and analysis of data on a local system. Finally, Oasis' modular workflow enables for the rapid (re-) analysis of data. Oasis is implemented in Python, R, Java, PHP, C++ and JavaScript. It is freely available at http://oasis.dzne.de. stefan.bonn@dzne.de Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.

HLB-associated preharvest fruit abscission is mediated by jasmonate/ethylene signaling triggered by secondary fungal infection

USDA-ARS?s Scientific Manuscript database

One symptom of citrus huanglongbing (HLB) is excessive pre-harvest fruit drop. Recently, higher incidence of Lasiodiplodia theobromae (Diplodia) was found in HLB-symptomatic orange calyx abscission zones (AZ-C) than in non-symptomatic fruit, and the infection was positively correlated with the reduc...

Our OASIS

ERIC Educational Resources Information Center

Bircher, Lisa S.; Sansenbaugher, Bonnie

2017-01-01

This article describes an elementary science summer day camp at East Palatine High School in East Palestine, Ohio, for students in grades K-4, aided by high school (grades 9-12) student mentors. The school's Outdoor Area for Studies in Science (OASIS) is used for formal and informal studies in science for an elementary science camp week. The camp…

Novel amide polar-embedded reversed-phase column for the fast liquid chromatography-tandem mass spectrometry method to determine polyether ionophores in environmental waters.

PubMed

Herrero, P; Borrull, F; Pocurull, E; Marcé, R M

2012-11-09

A fast chromatographic method has been developed that takes less than 5 min per run to determine five polyether ionophores with a novel amide polar-embedded reversed-phase column coupled to a triple quadrupole mass spectrometer. A comparison between Oasis HLB and Oasis MAX sorbents for the solid-phase extraction was done. Oasis HLB sorbent gave recoveries close to 90% and the repeatability (%RSD, 25-100 ng/L, n=3) of the method was less than 7% for all compounds in all matrices. The presence of polyether ionophores in environmental waters such as river water and sewage was investigated. Monensin and narasin were frequently determined in influent and effluent sewage at concentrations from 10 ng/L to 47 ng/L in influents and from 6 ng/L to 34 ng/L in effluents. In river waters, polyether ionophores were not detected in any sample. Copyright © 2012 Elsevier B.V. All rights reserved.

[Determination of five representative ultraviolet filters in water by gas chromatography-mass spectrometry].

PubMed

Ding, Yiran; Huang, Yun; Zhao, Tingting; Cai, Qian; Luo, Yu; Huang, Bin; Zhang, Yuxia; Pan, Xuejun

2014-06-01

A method for the determination of five representative organic UV filters: ethylhexyl methoxycinnamate (EHMC), benzophenone-3 (BP-3), 4-methylbenzylidene camphor (4-MBC), octocrylene (OC), homosalate (HMS) in water was investigated. The method was ased on derivatization, solid phase extraction (SPE), followed by determination with gas chromatography-mass spectrometry (GC-MS). The variables involved in the derivatization of BP-3 and HMS were optimized, and SPE conditions were studied. For derivatization, 100 microL N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) was used as derivatization reagent and reacted with BP-3 and HMS at 100 degrees C for 100 min. For SPE, the pH value of water sample was adjusted to 3-5. The Oasis HLB cartridges were employed and the solution of ethyl acetate and dichloromethane (1 : 1, v/v) was used as the eluting solvent, and good recoveries of the target compounds were obtained. The limits of detection (LODs) and the limits of quantification (LOQs) for the five target compounds in water samples were 0.5-1.2 ng/L and 1.4-4.0 ng/L, respectively. The recoveries of spiked water samples were 87.85%-102.34% with good repeatability and reproducibility (RSD < 5%, n = 3) for all the target compounds. Finally, the validated method was applied to analysis the representative UV filters in water samples collected from a wastewater treatment plant in Kunming city of Yunnan province.

Accurate determination of 3-alkyl-2-methoxypyrazines in wines by gas chromatography quadrupole time-of-flight tandem mass spectrometry following solid-phase extraction and dispersive liquid-liquid microextraction.

PubMed

Fontana, Ariel; Rodríguez, Isaac; Cela, Rafael

2017-09-15

A new reliable method for the determination 3-alkyl-2-methoxypyrazines (MPs) in wine samples based on the sequential combination of solid-phase extraction (SPE), dispersive liquid-liquid microextraction (DLLME) and gas chromatography (GC) quadrupole time-of-flight accurate tandem mass spectrometry (QTOF-MS/MS) is presented. Primary extraction of target analytes was carried out by using a reversed-phase Oasis HLB (200mg) SPE cartridge combined with acetonitrile as elution solvent. Afterwards, the SPE extract was submitted to DLLME concentration using 0.06mL carbon tetrachloride (CCl 4 ) as extractant. Under final working conditions, sample concentration factors above 379 times and limits of quantification (LOQs) between 0.3 and 2.1ngL -1 were achieved. Moreover, the overall extraction efficiency of the method was unaffected by the particular characteristics of each wine; thus, accurate results (relative recoveries from 84 to 108% for samples spiked at concentrations from 5 to 25ngL -1 ) were obtained using matrix-matched standards, without using standard additions over every sample. Highly selective chromatographic records were achieved considering a mass window of 5mDa, centered in the quantification product ion corresponding to each compound. Twelve commercial wines, elaborated with grapes from different varieties and geographical origins, were processed with the optimized method. The 2-isobutyl-3-methoxypyrazine (IBMP) was determined at levels above the LOQs of the method in half of the samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Simultaneous determination of mushroom toxins α-amanitin, β-amanitin and muscarine in human urine by solid-phase extraction and ultra-high-performance liquid chromatography coupled with ultra-high-resolution TOF mass spectrometry.

PubMed

Tomková, Jana; Ondra, Peter; Válka, Ivo

2015-06-01

This paper presents a method for the simultaneous determination of α-amanitin, β-amanitin and muscarine in human urine by solid-phase extraction (SPE) and ultra-high-performance liquid chromatography coupled with ultra-high-resolution TOF mass spectrometry. The method can be used for a diagnostics of mushroom poisonings. Different SPE cartridges were tested for sample preparation, namely hydrophilic modified reversed-phase (Oasis HLB) and polymeric weak cation phase (Strata X-CW). The latter gave better results and therefore it was chosen for the subsequent method optimization and partial validation. In the course of validation, limits of detection, linearity, intraday and interday precisions and recoveries were evaluated. The obtained LOD values of α-amanitin and β-amanitin were 1ng/mL and of muscarine 0.09ng/mL. The intraday and interday precisions of human urine spiked with α-amanitin (10ng/mL), β-amanitin (10ng/mL) and muscarine (1ng/mL) ranged from 6% to 10% and from 7% to 13%, respectively. The developed method was proved to be a relevant tool for the simultaneous determination of the studied mushroom toxins in human urine after mushroom poisoning. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Oasis 2: improved online analysis of small RNA-seq data.

PubMed

Rahman, Raza-Ur; Gautam, Abhivyakti; Bethune, Jörn; Sattar, Abdul; Fiosins, Maksims; Magruder, Daniel Sumner; Capece, Vincenzo; Shomroni, Orr; Bonn, Stefan

2018-02-14

Small RNA molecules play important roles in many biological processes and their dysregulation or dysfunction can cause disease. The current method of choice for genome-wide sRNA expression profiling is deep sequencing. Here we present Oasis 2, which is a new main release of the Oasis web application for the detection, differential expression, and classification of small RNAs in deep sequencing data. Compared to its predecessor Oasis, Oasis 2 features a novel and speed-optimized sRNA detection module that supports the identification of small RNAs in any organism with higher accuracy. Next to the improved detection of small RNAs in a target organism, the software now also recognizes potential cross-species miRNAs and viral and bacterial sRNAs in infected samples. In addition, novel miRNAs can now be queried and visualized interactively, providing essential information for over 700 high-quality miRNA predictions across 14 organisms. Robust biomarker signatures can now be obtained using the novel enhanced classification module. Oasis 2 enables biologists and medical researchers to rapidly analyze and query small RNA deep sequencing data with improved precision, recall, and speed, in an interactive and user-friendly environment. Oasis 2 is implemented in Java, J2EE, mysql, Python, R, PHP and JavaScript. It is freely available at https://oasis.dzne.de.

A generic method for the determination of acrylamide in thermally processed foods.

PubMed

Gökmen, Vural; Senyuva, Hamide Z

2006-07-07

A generic sample preparation method for the determination of acrylamide in foods was developed. The method entails extraction with methanol, purification with Carrez I and II solutions, evaporation and solvent change to water, and cleanup with Oasis HLB solid-phase extraction (SPE) cartridge. The final extract was analyzed by liquid chromatography-mass spectrometry (LC-MS) for quantitation. The chromatographic separation was performed on ODS-3 column using the isocratic mixture of 0.01 mM acetic acid in 0.2% aqueous solution of formic acid at a flow rate of 0.6 ml/min at 25 degrees C. The recoveries of acrylamide from potato chips, biscuits and coffee ranged between 92.8 and 101.5% with relative standard deviations of 4.1% or less. The limit of detection (LOD) and the limit of quantitation (LOQ) were 2 ng/g and 6 ng/g in the basis of signal to noise ratios of 3:1 and 9:1, respectively.

Risk-based HLB surveys: for southern California, statewide and targeted - an analysis of the increasing risk of HLB over the last five years

USDA-ARS?s Scientific Manuscript database

Evidence from Florida, and other citrus-producing areas of the world, clearly demonstrates that huanglongbing (HLB) is not a disease that can be managed effectively by individual growers. Rather, it is a disease which confronts the whole production industry and other stakeholders simultaneously. The...

Lunar oasis

NASA Technical Reports Server (NTRS)

Duke, Michael B.; Niehoff, John

1989-01-01

The 'lunar oasis' emphasizes development toward self-sufficiency in order to reduce dependence on the earth for resupply, and to enable expansion utilizing indigeneous resources. The oasis phase includes: (1) habitation and work facilities for 10 people, (2) capability for extraction of volatile consumables (H2O, O2, N2, etc.) from indigenous resources for resupply of losses and filling of reservoirs, and (3) a highly closed life support system, including food production. In the consolidation phase, the base grows from 10 to 30 crewmembers. Lunar resources are used for expanding the lunar foothold, including construction of habitats, extraction of metals for the fabrication of products for maintenance and repair, and expansion of the power system. The strategy does not produce propellants for space transportation. A 10-year scenario is laid out, which contains all elements needed to allow the base to enter a self-expanding utilization phase. Three lunar missions yer year, two cargo missions and one crew flight, are required. At the end of a decade, the base is producing more than it requires for its continued support, although it is unlikely to be completely self-sufficient.

Recreational value of an oasis in Oman.

PubMed

Zekri, Slim; Mbaga, Msafiri; Fouzai, Ayoub; Al-Shaqsi, Saif

2011-07-01

Increasing demand for water to develop non-agricultural activities is causing water to be diverted to high-value uses at the expense of irrigation. However, agriculture provides a flow of amenities in the desert environment which are not either accounted or paid. Oases are spread all over the globe and are threatened for various reasons among which is the high pressure of demand for fresh water. This paper estimates the recreation use value of an oasis. The paper is based on the Misfat Al-Abryeen oasis in Oman, a man-made area of streams and woodland. The travel cost method is used through an on-site questionnaire distributed to 230 visitors. Around 75% of visitors to the oasis also visited other historical or ecological sites during the same day-trip. The econometric model is estimated using negative binomial regression with endogenous stratification. The average consumer surplus, or benefit, from visiting Misfat Al-Abryeen is estimated at US$ 104.74 per individual per trip. The total social benefit from this oasis is estimated at $366,590 per year. These results underscore the importance of the role played by irrigated agriculture in the provision of amenity services for the tourism sector in a desert environment. The sustainability of the irrigation activity depends on the recognition of the recreation role of oases and the transfer of part of these benefits to the farmers who maintain the irrigation system. The implementation of an entrance fee to the oasis might increase farmers' profit by 6-21%.

Recreational Value of an Oasis in Oman

NASA Astrophysics Data System (ADS)

Zekri, Slim; Mbaga, Msafiri; Fouzai, Ayoub; Al-Shaqsi, Saif

2011-07-01

Increasing demand for water to develop non-agricultural activities is causing water to be diverted to high-value uses at the expense of irrigation. However, agriculture provides a flow of amenities in the desert environment which are not either accounted or paid. Oases are spread all over the globe and are threatened for various reasons among which is the high pressure of demand for fresh water. This paper estimates the recreation use value of an oasis. The paper is based on the Misfat Al-Abryeen oasis in Oman, a man-made area of streams and woodland. The travel cost method is used through an on-site questionnaire distributed to 230 visitors. Around 75% of visitors to the oasis also visited other historical or ecological sites during the same day-trip. The econometric model is estimated using negative binomial regression with endogenous stratification. The average consumer surplus, or benefit, from visiting Misfat Al-Abryeen is estimated at US 104.74 per individual per trip. The total social benefit from this oasis is estimated at 366,590 per year. These results underscore the importance of the role played by irrigated agriculture in the provision of amenity services for the tourism sector in a desert environment. The sustainability of the irrigation activity depends on the recognition of the recreation role of oases and the transfer of part of these benefits to the farmers who maintain the irrigation system. The implementation of an entrance fee to the oasis might increase farmers' profit by 6-21%.

Breeding citrus for HLB resistance at the USDA/ARS U.S. Horticultural Research Laboratory, Ft. Pierce, Florida

USDA-ARS?s Scientific Manuscript database

Citrus breeding has been conducted by the USDA since 1893. The initial objectives included improved disease-resistance, cold hardiness, and easy peeling fruit, which are still important breeding objectives today. The emergence of huanglongbing (HLB) in the US has propelled the development of HLB r...

OASIS General Introduction.

ERIC Educational Resources Information Center

Stanford Univ., CA.

Recognizing the need to balance generality and economy in system costs, the Project INFO team at Stanford University developing OASIS has sought to provide generalized and powerful computer support within the normal range of operating and analytical requirements associated with university administration. The specific design objectives of the OASIS…

Demonstration of obstacle avoidance system (OASYS) symbology in full mission simulation

NASA Astrophysics Data System (ADS)

Sharkey, Thomas J.

1994-06-01

The U. S. Army Aeroflightdynamics Directorate's (AFDD) Crew Station Research and Development Branch (CSRDB) conducted a multiphase effort to develop symbology displaying information from the Obstacle Avoidance System (OASYS) on the Aviator's Night Vision System (ANVIS) Head Up Display (HUD). The first phase of this program used static symbology displayed on a workstation to identify the types of information required from OASYS by the pilot. The second phase used a low-fidelity, pilot-in-the-loop simulation to evaluate fourteen different symbology-drive law combinations. Based on the results of phases 1 and 2 three candidate symbologies were selected, along with the baseline symbology developed by the OASYS contractor, for evaluation in full mission simulation. In addition, a full-daylight, full field-of-view condition and Night Vision Goggle (NVG) condition, both without OASYS symbology, were used as control conditions. The environmental conditions (e.g., ambient illumination, visual range) and task requirements (e.g., altitude and airspeed) used in the simulation were selected to severely tax the symbology. Reliable differences in performance between symbology conditions were found. Two of the symbologies developed during the earlier phases of this program resulted in reduced frequencies of ground strikes compared to OASYS baseline and NVG only conditions. The frequency of close approaches to wires was lower with the symbology developed in this program than with the baseline symbology. All OASYS symbologies improved performance relative to the NVG control condition. It is recommended that the OASYS symbology and drive laws developed during this program be used during OASYS flight tests.

Discovery of huanglongbing (HLB) pre-symptomatic Ribonucleic acid (RNA) biomarkers

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB) is the most devastating citrus disease and is associated with vector-borne Liberibacter. Currently there is no cure for huanglongbing. Visual disease symptoms appear in only a few leaves months after initial Liberibacter exposure compromising disease management by tree removal. S...

Long-term outcomes of the Stop Traumatic OASI Morbidity Project (STOMP).

PubMed

Basu, Maya; Smith, Dot

2018-06-09

To evaluate long-term sustainability of the Stop Traumatic OASI Morbidity Project (STOMP) in reducing the incidence of obstetric anal sphincter injury (OASI). A prospective observational study of women undergoing vaginal delivery at a UK district general hospital between September 1, 2014, and February 28, 2017. The principles of STOMP involve encouraging upright positioning, verbal coaching to avoid expulsive pushing and to slow down delivery, and tactile support to the vertex to judge speed and slow down delivery. After a training period, STOMP was implemented for all vaginal deliveries. Clinical and demographic data on women affected by OASI were collected across a 30-month period. The primary outcome measure was the incidence of OASI. There were 8782 vaginal deliveries during the 30-month period after implementation of STOMP. There was a significant decrease in the mean incidence of OASI relative to the 9 months before implementation (P<0.001). There was a significant decrease in the incidence of OASI for both spontaneous vaginal and instrumental deliveries (both P<0.05). There was no change in the frequency of episiotomy. Implementation of STOMP led to a significant decrease in OASI, confirming the sustainability of this approach to improve outcomes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Effect of Huanglongbing (HLB) disease on orange juice flavor

USDA-ARS?s Scientific Manuscript database

The disease, Huanglongbing (HLB), also called greening or yellow dragon disease was first discovered in Florida in 2005. This is a serious disease of citrus that can kill the tree in 5-10 years. It has also been rumored that the disease causes off-flavor in the fruit and subsequent juice that has be...

OASIS: A Data Fusion System Optimized for Access to Distributed Archives

NASA Astrophysics Data System (ADS)

Berriman, G. B.; Kong, M.; Good, J. C.

2002-05-01

The On-Line Archive Science Information Services (OASIS) is accessible as a java applet through the NASA/IPAC Infrared Science Archive home page. It uses Geographical Information System (GIS) technology to provide data fusion and interaction services for astronomers. These services include the ability to process and display arbitrarily large image files, and user-controlled contouring, overlay regeneration and multi-table/image interactions. OASIS has been optimized for access to distributed archives and data sets. Its second release (June 2002) provides a mechanism that enables access to OASIS from "third-party" services and data providers. That is, any data provider who creates a query form to an archive containing a collection of data (images, catalogs, spectra) can direct the result files from the query into OASIS. Similarly, data providers who serve links to datasets or remote services on a web page can access all of these data with one instance of OASIS. In this was any data or service provider is given access to the full suite of capabilites of OASIS. We illustrate the "third-party" access feature with two examples: queries to the high-energy image datasets accessible from GSFC SkyView, and links to data that are returned from a target-based query to the NASA Extragalactic Database (NED). The second release of OASIS also includes a file-transfer manager that reports the status of multiple data downloads from remote sources to the client machine. It is a prototype for a request management system that will ultimately control and manage compute-intensive jobs submitted through OASIS to computing grids, such as request for large scale image mosaics and bulk statistical analysis.

Effect of abscission zone formation on orange (Citrus sinensis) fruit/juice quality for trees affected by Huanglongbing (HLB)

USDA-ARS?s Scientific Manuscript database

Orange trees affected by huanglongbing (HLB) exhibit excessive fruit drop, and fruit loosely attached to the tree may have inferior flavor. Fruit were collected from healthy and HLB-infected (Candidatus liberibacter asiaticus) ‘Hamlin’ and ‘Valencia’ trees. Prior to harvest, the trees were shaken, f...

SPE-5 Ground-Motion Prediction at Far-Field Geophone and Accelerometer Array Sites and SPE-5 Moment and Corner-Frequency Prediction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Xiaoning; Patton, Howard John; Chen, Ting

2016-03-25

This report offers predictions for the SPE-5 ground-motion and accelerometer array sites. These predictions pertain to the waveform and spectral amplitude at certain geophone sites using Denny&Johnson source model and a source model derived from SPE data; waveform, peak velocity and peak acceleration at accelerometer sites using the SPE source model and the finite-difference simulation with LLNL 3D velocity model; and the SPE-5 moment and corner frequency.

Application of the unified mask data format based on OASIS for VSB EB writers

NASA Astrophysics Data System (ADS)

Suzuki, Toshio; Hirumi, Junji; Suga, Osamu

2005-11-01

Mask data preparation (MDP) for modern mask manufacturing becomes a complex process because many kinds of EB data formats are used in mask makers and EB data files continue to become bigger by the application of RET. Therefore we developed a unified mask pattern data format named "OASIS.VSB1" and a job deck format named "MALY2" for Variable-Shaped-Beam (VSB) EB writers. OASIS.VSB is the mask pattern data format based on OASISTM 3 (Open Artwork System Interchange Standard) released as a successive format to GDSII by SEMI. We defined restrictions on OASIS for VSB EB writers to input OASIS.VSB data directly to VSB EB writers just like the native EB data. OASIS.VSB specification and MALY specification have been disclosed to the public and will become a SEMI standard in the near future. We started to promote the spread activities of OASIS.VSB and MALY. For practical use of OASIS.VSB and MALY, we are discussing the infrastructure system of MDP processing using OASIS.VSB and MALY with mask makers, VSB EB makers, and device makers. We are also discussing the tools for the infrastructure system with EDA vendors. The infrastructure system will enable TAT, the man-hour, and the cost in MDP to be reduced. In this paper, we propose the plan of the infrastructure system of MDP processing using OASIS.VSB and MALY as an application of OASIS.VSB and MALY.

Spatial distribution of an ancient agricultural oasis in Juyan, northwestern China

NASA Astrophysics Data System (ADS)

Hu, Ningke; Li, Xin

2014-09-01

Activities related to agricultural cultivation are some of the major human drivers of landscape change on the Earth's surface. Archaeological remains can provide qualitative evidence for studies of past agricultural development and environmental conditions. The ancient Juyan Oasis, which once flourished along the historic Silk Road, was a typical oasis of downstream inland river basins in the arid zone of northwestern China. Historical records and archaeological discoveries have qualitatively shown that the oasis supported extensive agricultural activities in this historical period from the Han Dynasty to the early Ming Dynasty (B.C. 202-A.D. 1375), which can be traced back to 2,000 years ago. In this study, different types of archaeological remains (including archaeological sites, ground surface artifacts, ancient cultivation ruins, and agricultural irrigation canals) that were obtained and identified from previous archaeological reports, field inspections, and remote sensing imagery were used to determine the spatial extent of the agricultural oasis in the historical period of interest. Our approach used multiple data sources in order to increase the accuracy and reliability of the results compared to previous studies. Our results distinctly suggested that much of the oasis was cultivated during the historical periods considered. Additionally, the arable land area in the historical period considered was roughly estimated to be approximately (3.39-4.75) × 104 ha. These findings regarding the spatial distribution of this ancient agricultural oasis and its arable land were reasonably determined to represent the ancient agricultural development that occurred in the Juyan Oasis better than results obtained from single sources of data.

[Spatial change of the grain-size of aeolian sediments in Qira oasis-desert ecotone, Northwest China].

PubMed

Lin, Yong Chong; Xu, Li Shuai

2017-04-18

In order to understand the environmental influence of oasis-desert ecotone to oasis ecological system, we comparatively analyzed the grain size characteristics of various aeolian sediments, including the sediments in oasis-desert ecotone, shelterbelt and the inside oasis and in Qira River valley. The results showed that the grain size characteristics (including grain-size distribution curve, grain size parameters, and content of different size classes) of sediments in the oasis-desert ecotone were consistent along the prevailing wind direction with a grain-size range of 0.3-200 μm and modal size of 67 μm. All of the sediments were good sorting and mainly composed of suspension components and saltation components, but not denatured saltation and creeping components (>200 μm). They were typically aeolian deposits being short-range transported. The grain sizes of sediments in oasis-desert ecotone were smaller than that in the material sources of Qira River valley and desert (0.3-800 μm), but very similar to those of the modern aeolian deposits in oasis-desert ecotone, shelterbelt and the inside oasis. The denatured saltation and creep components (>200 μm) were suppressed to transport into oasis-desert ecotone because of the high vegetation cover in oasis-desert ecotone. Therefore, like the shelterbelts, the oasis-desert ecotone could also block the invasion of desert. They safeguarded the oasis ecological environment together.

Simultaneous determination of 29 pharmaceuticals in fish muscle and plasma by ultrasonic extraction followed by SPE-UHPLC-MS/MS.

PubMed

Liu, You-Yu; Hu, Xia-Lin; Bao, Yi-Fan; Yin, Da-Qiang

2018-02-12

A confirmatory method for the simultaneous detection of 29 pharmaceuticals in fish muscle and plasma was developed by using solid-phase extraction combined with ultra high performance liquid chromatography and tandem mass spectrometry. Fish samples were extracted with methanol and enriched using Oasis HLB solid-phase extraction columns in one step. Twenty-nine target pharmaceuticals were quantified by the internal standard method and the calibration curves showed good linearity in a wide range with determination coefficients of greater than 0.913. The detection limits of the pharmaceuticals ranged from 0.01 to 2.00 μg/kg (μg/L). The applicability of the method was checked by precision and recovery experiments. The average recoveries of the 29 pharmaceuticals were between 61 and 111%, and all the relative standard deviations were below 25%. Our reported method has been demonstrated to be sensitive, convenient, rapid and reliable for the simultaneous determination of 29 pharmaceuticals in fish muscle and plasma. Real sample determination showed that 25 and 9 of the 29 compounds were detected in fish muscle and plasma, respectively. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

The Outcome and Assessment Information Set (OASIS): A Review of Validity and Reliability

PubMed Central

O’CONNOR, MELISSA; DAVITT, JOAN K.

2015-01-01

The Outcome and Assessment Information Set (OASIS) is the patient-specific, standardized assessment used in Medicare home health care to plan care, determine reimbursement, and measure quality. Since its inception in 1999, there has been debate over the reliability and validity of the OASIS as a research tool and outcome measure. A systematic literature review of English-language articles identified 12 studies published in the last 10 years examining the validity and reliability of the OASIS. Empirical findings indicate the validity and reliability of the OASIS range from low to moderate but vary depending on the item studied. Limitations in the existing research include: nonrepresentative samples; inconsistencies in methods used, items tested, measurement, and statistical procedures; and the changes to the OASIS itself over time. The inconsistencies suggest that these results are tentative at best; additional research is needed to confirm the value of the OASIS for measuring patient outcomes, research, and quality improvement. PMID:23216513

Delineation of the Pahute Mesa–Oasis Valley groundwater basin, Nevada

USGS Publications Warehouse

Fenelon, Joseph M.; Halford, Keith J.; Moreo, Michael T.

2016-01-22

This report delineates the Pahute Mesa–Oasis Valley (PMOV) groundwater basin, where recharge occurs, moves downgradient, and discharges to Oasis Valley, Nevada. About 5,900 acre-feet of water discharges annually from Oasis Valley, an area of springs and seeps near the town of Beatty in southern Nevada. Radionuclides in groundwater beneath Pahute Mesa, an area of historical underground nuclear testing at the Nevada National Security Site, are believed to be migrating toward Oasis Valley. Delineating the boundary of the PMOV groundwater basin is necessary to adequately assess the potential for transport of radionuclides from Pahute Mesa to Oasis Valley.The PMOV contributing area is defined based on regional water-level contours, geologic controls, and knowledge of adjacent flow systems. The viability of this area as the contributing area to Oasis Valley and the absence of significant interbasin flow between the PMOV groundwater basin and adjacent basins are shown regionally and locally. Regional constraints on the location of the contributing area boundary and on the absence of interbasin groundwater flow are shown by balancing groundwater discharges in the PMOV groundwater basin and adjacent basins against available water from precipitation. Internal consistency for the delineated contributing area is shown by matching measured water levels, groundwater discharges, and transmissivities with simulated results from a single-layer, steady-state, groundwater-flow model. An alternative basin boundary extending farther north than the final boundary was rejected based on a poor chloride mass balance and a large imbalance in the northern area between preferred and simulated recharge.

Validation of SWEEP for creep, saltation, and suspension in a desert-oasis ecotone

USDA-ARS?s Scientific Manuscript database

Wind erosion in the desert-oasis ecotone can accelerate desertification and thus impacts oasis ecological security. Little is known about the susceptibility of the desert-oasis ecotone to wind erosion in the Tarim Basin even though the ecotone is a major source of windblown dust in China. The object...

Analysis of coffee for the presence of acrylamide by LC-MS/MS.

PubMed

Andrzejewski, Denis; Roach, John A G; Gay, Martha L; Musser, Steven M

2004-04-07

A variety of popular instant, ground, and brewed coffees were analyzed using a modified liquid chromatography-tandem mass spectrometry (LC-MS/MS) method specifically developed for the determination of acrylamide in foods. Coffee test portions were spiked with 13C3-labeled acrylamide as an internal standard prior to their extraction and cleanup. Ground coffees (1 g) and instant coffees (0.5 g) were extracted by shaking with 9 mL of water for 20 min. Brewed coffee test portions (9 mL) were taken through the cleanup procedure without further dilution with extraction solvent. Coffee test portions were cleaned up by passing 1.5 mL first through an Oasis HLB (hydrophilic/lipophilic copolymer sorbent) solid phase extraction (SPE) cartridge and then a Bond Elut-Accucat (cation and anion exchange sorbent) SPE cartridge. The cleaned up extracts were analyzed by positive ion electrospray LC-MS/MS. The MS/MS data was used to detect, confirm, and quantitate acrylamide. The limit of quantitation of the method was 10 ng/g for ground and instant coffees and 1.0 ng/mL for brewed coffee. The levels of acrylamide ranged from 45 to 374 ng/g in unbrewed coffee grounds, from 172 to 539 ng/g in instant coffee crystals, and from 6 to 16 ng/mL in brewed coffee.

Profile Changes in the Soil Microbial Community When Desert Becomes Oasis

PubMed Central

Li, Chen-hua; Tang, Li-song; Jia, Zhong-jun; Li, Yan

2015-01-01

The conversion of virgin desert into oasis farmland creates two contrasting types of land-cover. During oasis formation with irrigation and fertilizer application, however, the changes in the soil microbial population, which play critical roles in the ecosystem, remain poorly understood. We applied high-throughput pyrosequencing to investigate bacterial and archaeal communities throughout the profile (0–3 m) in an experimental field, where irrigation and fertilization began in 1990 and cropped with winter wheat since then. To assess the effects of cultivation, the following treatments were compared with the virgin desert: CK (no fertilizer), PK, NK, NP, NPK, NPKR, and NPKM (R: straw residue; M: manure fertilizer). Irrigation had a greater impact on the overall microbial community than fertilizer application. The greatest impact occurred in topsoil (0–0.2 m), e.g., Cyanobacteria (25% total abundance) were most abundant in desert soil, while Actinobacteria (26%) were most abundant in oasis soil. The proportions of extremophilic and photosynthetic groups (e.g., Deinococcus-Thermus and Cyanobacteria) decreased, while the proportions of R-strategy (e.g., Gammaproteobacteria including Xanthomonadales), nitrifying (e.g., Nitrospirae), and anaerobic bacteria (e.g., Anaerolineae) increased throughout the oasis profile. Archaea occurred only in oasis soil. The impact of fertilizer application was mainly reflected in the non-dominant communities or finer taxonomic divisions. Oasis formation led to a dramatic shift in microbial community and enhanced soil enzyme activities. The rapidly increased soil moisture and decreased salt caused by irrigation were responsible for this shift. Furthermore, difference in fertilization and crop growth altered the organic carbon contents in the soil, which resulted in differences of microbial communities within oasis. PMID:26426279

The spatio-temporal variability of groundwater depth in a typical desert-oasis ecotone

NASA Astrophysics Data System (ADS)

Wang, Guohua; Zhao, Wenzhi

2015-06-01

Eight groundwater observation wells were installed along the river plain, where the landscapes varied from floodplain, to oasis farmland, to desert-oasis ecotone to desert, in a typical desert-oasis ecotone in northwestern China. Ten years of data were used to analyze temporal and spatial changes in the groundwater depth. The results indicated that in the last decade: (1) the groundwater depths in the floodplain (GW1) and the desert (GW8) were basically stable; (2) the groundwater depths in the oasis farmland (GW2, GW3, GW4) increased dramatically: the annual fluctuations were 1.43, 1.01 and 0.79 m respectively, with the groundwater depths increasing by 0.13-0.18 m every year; (3) the groundwater depths in the desert-oasis ecotone (GW5, GW6, GW7) also increased dramatically: the annual fluctuations were 1.10, 1.06 and 1.05 m respectively, and the depths increased by 0.10-0.15 m every year; (4) the influence distance between the river and both the farmland and the desert-oasis ecotone was about 1000-2000 m in the study area. These results show that the natural seasonal fluctuation influence on groundwater depths was not significant, but the human-induced fluctuations such as intensive irrigation caused a significant increase in groundwater depth in both the farmland and the desert-oasis ecotone, seriously affecting sustainable agriculture development and the environment, in the oasis.

SPE (tm) water electrolyzers in support of mission from planet Earth

NASA Technical Reports Server (NTRS)

Mcelroy, J. F.

1991-01-01

During the 1970's, the Solid Polymer Electrolyte (SPE) water electrolyzer, which uses ion exchange membranes as its sole electrolyte, was developed for nuclear submarine metabolic oxygen production. SPE water electrolyzer developments included operation at up to 3,000 psia and at current densities in excess of 1,000 amps per square foot. The SPE water electrolyzer system has accumulated tens of thousands of system hours with the Navies of both the United States and the United Kingdom. During the 1980's, the basic SPE water electrolyzer cell structure developed for the Navies was incorporated into several demonstrators for NASA's Space Station Program. Among these were: (1) the SPE regenerative fuel cell for electrical energy storage; (2) the SPE water electrolyzer for metabolic oxygen production; and (3) the high pressure SPE water electrolyzer for reboost propellant production. In the 1990's, emphasis will be the development of SPE water electrolyzers for Mission from Planet Earth. Currently defined potential applications for the SPE water electrolyzer include: (1) SPE water electrolyzers operating at high pressure as part of a regenerative fuel cell extraterrestrial surface energy storage system; (2) SPE water electrolyzers for propellant production from extraterrestrial indigenous materials; and (3) SPE water electrolyzers for metabolic oxygen and potable water production from reclaimed water.

Adoption and validation of Ribonucleotide Reductase (RNR)-based real-time assays for detection of HLB ‘Candidatus Liberibacter asiaticus’ (CLas)

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB), aka Citrus Greening, is a well-known destructive disease that threatens the multi-billion dollar citrus industry in the United States and citrus production in other countries around the world. The presumptive causal agent of HLB, ‘Candidatus Liberibacter asiaticus' (CLas), is of...

Histopathological assessment of OASIS Ultra on critical-sized wound healing: a pilot study.

PubMed

Yeh, Daniel Dante; Nazarian, Rosalynn M; Demetri, Leah; Mesar, Tomaz; Dijkink, Suzan; Larentzakis, Andreas; Velmahos, George; Sadik, Karim Walid

2017-06-01

Dermatopathologists assess wounds secondary to trauma, infection, or oncologic resection that can be challenging to reconstruct. OASIS Ultra, an extracellular matrix, has been described for use in chronic and burn wounds. The aim of this pilot study is to assess wound healing in post-traumatic and infective wounds treated with OASIS using histological markers of repair. Adults with traumatic, infective or iatrogenic wound defects with size precluding primary closure were eligible. Half the wound was randomly assigned to receive OASIS plus standard therapy; the other half received standard of care (SOC) therapy. During dressing changes, standardized-scale photographs were taken and biopsies obtained. Histologic sections were reviewed for degree of acute inflammation and extent of tissue repair. Neutrophils, edema, hemorrhage, necrosis, fibroblasts, collagen density and neovascularization were semi-quantitatively assessed. Forty-four skin biopsies from 7 patients with 10 acute wounds met eligibility criteria. Histologically, OASIS samples demonstrated improved acute inflammation scores compared to SOC. No patients experienced OASIS-related complications. OASIS-treated wound halves trended toward more wound contraction and improved tissue repair. Our scoring system aids histopathological wound assessment. Treatment of critical-sized, post-traumatic, acute wounds with OASIS resulted in decreased inflammation, and potentially more advanced wound healing, compared to SOC. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Analysis of perfluorooctanoate (PFOA) and other perfluorinated compounds (PFCs) in the River Po watershed in N-Italy.

PubMed

Loos, Robert; Locoro, Giovanni; Huber, Tania; Wollgast, Jan; Christoph, Eugen H; de Jager, Alfred; Manfred Gawlik, Bernd; Hanke, Georg; Umlauf, Gunther; Zaldívar, José-Manuel

2008-03-01

C7-C11 perfluorinated carboxylates (PFACs) and perfluorooctansulfonate (PFOS) were analysed in selected stretches of the River Po and its major tributaries. Analyses were performed by solid-phase extraction (SPE) with Oasis HLB cartridges and methanol elution followed by LC-MS-MS detection using 13C-labelled internal standards. High concentration levels ( approximately 1.3 microg l(-1)) of perfluorooctanoate (PFOA) were detected in the Tánaro River close to the city Alessandria. After this tributary, levels between 60 and 337 ng l(-1) were measured in the Po River on several occasions. The PFOA concentration close to the river mouth in Ferrara was between 60 and 174 ng l(-1). Using the river discharge flow data in m3 s(-1) at this point (average approximately 920 m3 s(-1) for the year 2006), a mass load of approximately 0.3 kg PFOA per hour or approximately 2.6 tons per year discharged in the Adriatic Sea has been calculated. PFOS concentration levels in the Po River at Ferrara were approximately 10 ng l(-1).

Quantitative determination of 5-hydroxy-N-methylpyrrolidone in urine for biological monitoring of N-methylpyrrolidone exposure.

PubMed

Ligocka, D; Lison, D; Haufroid, V

2002-10-05

The aim of this work was to validate a sensitive method for quantitative analysis of 5-hydroxy-N-methylpyrrolidone (5-HNMP) in urine. This compound has been recommended as a marker for biological monitoring of N-methylpyrrolidone (NMP) exposure. Different solvents and alternative methods of extraction including liquid-liquid extraction (LLE) on Chem Elut and solid-phase extraction (SPE) on Oasis HLB columns were tested. The most efficient extraction of 5-HNMP in urine was LLE with Chem Elut columns and dichloromethane as a solvent (consistently 22% of recovery). The urinary extracts were derivatized by bis(trimethylsilyl)trifluoroacetamide and analysed by gas chromatography-mass spectrometry (GC-MS) with tetradeutered 5-HNMP as an internal standard. The detection limit of this method is 0.017 mg/l urine with an intraassay precision of 1.6-2.6%. The proposed method of extraction is simple and reproducible. Four different m/z signal ratios of TMS-5-HNMP and tetralabelled TMS-5-HNMP have been validated and could be indifferently used in case of unexpected impurities from urine matrix. Copyright 2002 Elsevier Science B.V.

Analysis of oxytetracycline in water using a portable analyzer

NASA Astrophysics Data System (ADS)

Chen, Guoying; Braden, Susan; Qin, Feng

2006-10-01

Oxytetracycline (OTC) is extensively used in aquaculture worldwide for preventive and therapeutic purposes. Most of the drug, however, is discharged into the marine environment due to leaching from medicated feed and poor gastrointestinal (GI) absorption. Without exposure to sun light OTC has a long lifetime in the marine environment, therefore it is important to monitor and study its occurrence, distribution, fate and impact on the ecosystem. A portable tetracycline (TC) analyzer was developed in this laboratory for this purpose based on europium-sensitized luminescence. In this study, an assay method is developed for OTC analysis in water using this instrument. Water samples are filtered with glass wool; and solid phase extraction (SPE) is performed using Oasis HLB cartridges for OTC extraction and cleanup. Following reagent application, the samples are excited by 385 nm LED pulses; and time-resolved luminescence (TRL) is measured at 610 nm by a photomultiplier tube. A 0-3 ppm linear dynamic range (r2 = 0.9988) and a 0.021 ppb limit of detection were achieved with a typical <5% relative standard deviation.

HLB1 Is a Tetratricopeptide Repeat Domain-Containing Protein That Operates at the Intersection of the Exocytic and Endocytic Pathways at the TGN/EE in Arabidopsis

DOE PAGES

Sparks, J. Alan; Kwon, Taegun; Renna, Luciana; ...

2016-03-03

The endomembrane system plays essential roles in plant development, but the proteome responsible for its function and organization remains largely uncharacterized in plants. For this study, we identified and characterized the HYPERSENSITIVE TO LATRUNCULIN B1 (HLB1) protein isolated through a forward-genetic screen in Arabidopsis thaliana for mutants with heightened sensitivity to actin-disrupting drugs. HLB1 is a plant-specific tetratricopeptide repeat domain-containing protein of unknown function encoded by a single Arabidopsis gene. HLB1 associated with the trans-Golgi network (TGN)/early endosome (EE) and tracked along filamentous actin, indicating that it could link post-Golgi traffic with the actin cytoskeleton in plants. HLB1 was foundmore » to interact with the ADP-ribosylation-factor guanine nucleotide exchange factor, MIN7/BEN1 (HOPM INTERACTOR7/BREFELDIN A-VISUALIZED ENDOCYTIC TRAFFICKING DEFECTIVE1) by coimmunoprecipitation. The min7/ben1 mutant phenocopied the mild root developmental defects and latrunculin B hypersensitivity of hlb1, and analyses of a hlb1/ min7/ben1 double mutant showed that hlb1 and min7/ben1 operate in common genetic pathways. Based on these data, we propose that HLB1 together with MIN7/BEN1 form a complex with actin to modulate the function of the TGN/EE at the intersection of the exocytic and endocytic pathways in plants.« less

Quantitative distribution of Candidatus Liberibacter asiaticus in the aerial parts of the field grown HLB-infected citrus trees in Texas

USDA-ARS?s Scientific Manuscript database

The Asian citrus psyllid, Diaphorina citri Kuwayanna, one of the vectors for citrus greening disease or Huanglongbing (HLB) has been present in Texas for over a decade, but the detection of the disease is recent. HLB has been confirmed in only two adjacent commercial citrus groves of grapefruit and...

New Insights into the Explosion Source from SPE

NASA Astrophysics Data System (ADS)

Patton, H. J.

2015-12-01

Phase I of the Source Physics Experiments (SPE) is a series of chemical explosions at varying depths and yields detonated in the same emplacement hole on Climax stock, a granitic pluton located on the Nevada National Security Site. To date, four of the seven planned tests have been conducted, the last in May 2015, called SPE-4P, with a scaled depth of burial of 1549 m/kt1/3 in order to localize the source in time and space. Surface ground motions validated that the source medium did not undergo spallation, and a key experimental objective was achieved where SPE-4P is the closest of all tests in the series to a pure monopole source and will serve as an empirical Green's function for analysis against other SPE tests. A scientific objective of SPE is to understand mechanisms of rock damage for generating seismic waves, particularly surface and S waves, including prompt damage under compressive stresses and "late-time" damage under tensile stresses. Studies have shown that prompt damage can explain ~75% of the seismic moment for some SPE tests. Spallation is a form of late-time damage and a facilitator of damage mechanisms under tensile stresses including inelastic brittle deformation and shear dilatancy on pre-existing faults or joints. As an empirical Green's function, SPE-4P allows the study of late-time damage mechanisms on other SPE tests that induce spallation and late-time damage, and I'll discuss these studies. The importance for nuclear monitoring cannot be overstated because new research shows that damage mechanisms can affect surface wave magnitude Ms more than tectonic release, and are a likely factor related to anomalous mb-Ms behavior for North Korean tests.

An Evaluation of Operational Airspace Sectorization Integrated System (OASIS) Advisory Tool

NASA Technical Reports Server (NTRS)

Lee, Paul U.; Mogford, Richard H.; Bridges, Wayne; Buckley, Nathan; Evans, Mark; Gujral, Vimmy; Lee, Hwasoo; Peknik, Daniel; Preston, William

2013-01-01

In January 2013, a human-in-the-loop evaluation of the Operational Airspace Sectorization Integrated System (OASIS) was conducted in the Airspace Operations Laboratory of the Human Systems Integration Division (Code TH) in conjunction with the Aviation Systems Division (Code AF). The development of OASIS is a major activity of the Dynamic Airspace Configuration (DAC) research focus area within the Aeronautics Research Mission Directorate (ARMD) Airspace Systems Program. OASIS is an advisory tool to assist Federal Aviation Administration (FAA) En Route Area Supervisors in their planning of sector combinedecombine operations as well as opening closing of Data-side (D-side) control positions. These advisory solutions are tailored to the predicted traffic demand over the next few hours. During the experiment, eight retired FAA personnel served as participants for a part-task evaluation of OASIS functionality, covering the user interface as well as the underlying algorithm. Participants gave positive feedback on both the user interface and the algorithm solutions for airspace configuration, including an excellent average rating of 94 on the tool usability scales. They also suggested various enhancements to the OASIS tool, which will be incorporated into the next tool development cycle for the full-scale human-in-the-loop evaluation to be conducted later this year.

Expansion of agricultural oasis in the Heihe River Basin of China: Patterns, reasons and policy implications

NASA Astrophysics Data System (ADS)

Song, Wei; Zhang, Ying

The Heihe River Basin (HRB) is the second largest inland river basin in the arid region of northwestern China. An agricultural oasis is a typical landscape in arid regions providing precious fertile soil, living space and ecological services. The agricultural oasis change has been one of the key issues in sustainable development in recent decades. In this paper, we examined the changes in the agricultural oasis in HRB and analyzed the socio-economic and climatic driving forces behind them. It was found that the agricultural oasis in HRB expanded by 25.11% and 14.82% during the periods of 1986-2000 and 2000-2011, respectively. Most of the newly added agricultural oases in HRB were converted from grassland (40.94%) and unused land (40.22%). The expansion in the agricultural oasis mainly occurred in the middle reaches of HRB, particularly in the counties of Shandan, Minle, Jinta and Jiuquan city. Changes in the rural labor force, annual temperature and precipitation have significant positive effects on agricultural oasis changes, while the ratio of irrigated agricultural oases has significant negative effects on agricultural oasis changes. The agricultural oasis expansion in HRB is the combined effect of human activity and climate change.

Transgenic Citrus Expressing an Arabidopsis NPR1 Gene Exhibit Enhanced Resistance against Huanglongbing (HLB; Citrus Greening).

PubMed

Dutt, Manjul; Barthe, Gary; Irey, Michael; Grosser, Jude

2015-01-01

Commercial sweet orange cultivars lack resistance to Huanglongbing (HLB), a serious phloem limited bacterial disease that is usually fatal. In order to develop sustained disease resistance to HLB, transgenic sweet orange cultivars 'Hamlin' and 'Valencia' expressing an Arabidopsis thaliana NPR1 gene under the control of a constitutive CaMV 35S promoter or a phloem specific Arabidopsis SUC2 (AtSUC2) promoter were produced. Overexpression of AtNPR1 resulted in trees with normal phenotypes that exhibited enhanced resistance to HLB. Phloem specific expression of NPR1 was equally effective for enhancing disease resistance. Transgenic trees exhibited reduced diseased severity and a few lines remained disease-free even after 36 months of planting in a high-disease pressure field site. Expression of the NPR1 gene induced expression of several native genes involved in the plant defense signaling pathways. The AtNPR1 gene being plant derived can serve as a component for the development of an all plant T-DNA derived consumer friendly GM tree.

Evaluation of the Nutritional Changes Caused by Huanglongbing (HLB) to Citrus Plants Using Laser-Induced Breakdown Spectroscopy.

PubMed

Ranulfi, Anielle Coelho; Romano, Renan Arnon; Bebeachibuli Magalhães, Aida; Ferreira, Ednaldo José; Ribeiro Villas-Boas, Paulino; Marcondes Bastos Pereira Milori, Débora

2017-07-01

Huanglongbing (HLB) is the most recent and destructive bacterial disease of citrus and has no cure yet. A promising alternative to conventional methods is to use laser-induced breakdown spectroscopy (LIBS), a multi-elemental analytical technique, to identify the nutritional changes provoked by the disease to the citrus leaves and associate the mineral composition profile with its health status. The leaves were collected from adult citrus trees and identified by visual inspection as healthy, HLB-symptomatic, and HLB-asymptomatic. Laser-induced breakdown spectroscopy measurements were done in fresh leaves without sample preparation. Nutritional variations were evaluated using statistical tools, such as Student's t-test and analysis of variance applied to LIBS spectra, and the largest were found for Ca, Mg, and K. Considering the nutritional profile changes, a classifier induced by classification via regression combined with partial least squares regression was built resulting in an accuracy of 73% for distinguishing the three categories of leaves.

Combining remote sensing image with DEM to identify ancient Minqin Oasis, northwest of China

NASA Astrophysics Data System (ADS)

Xie, Yaowen

2008-10-01

The developing and desertification process of Minqin oasis is representative in the whole arid area of northwest China. Combining Remote Sensing image with Digital Elevation Model (DEM) can produce the three-dimensional image of the research area which can give prominence to the spatial background of historical geography phenomenon's distribution, providing the conditions for extracting and analyzing historical geographical information thoroughly. This research rebuilds the ancient artificial Oasis based on the three-dimensional images produced by the TM digital Remote Sensing image and DEM created using 1:100000 topographic maps. The result indicates that the whole area of the ancient artificial oasis in Minqin Basin over the whole historical period reaches 321km2, in the form of discontinuous sheet, separated on the two banks of ancient Shiyang River and its branches, namely, Xishawo area, west to modern Minqin Basin and Zhongshawo area, in the center of the oasis. Except for a little of the ancient oasis unceasingly used by later people, most of it became desert. The combination of digital Remote Sensing image and DEM can integrate the advantages of both in identifying ancient oasis and improve the interpreting accuracy greatly.

Geological heritage diversity in the Faiyum Oasis (Egypt): A comprehensive assessment

NASA Astrophysics Data System (ADS)

Sallam, Emad S.; Fathy, Esraa E.; Ruban, Dmitry A.; Ponedelnik, Alena A.; Yashalova, Natalia N.

2018-04-01

The Faiyum Oasis in the Western Desert of Egypt is famous for its palaeontological localities (Cenozoic whales, primates, etc.) of global importance, but its geological heritage has been not studied in the modern theoretical frame. The new investigation based on the field studies and the literature review permits comprehensive assessment of the geological heritage diversity in this oasis. For this purposes, unique geological features are inventoried with establishment of their geological essence, rank, relative abundance, and intrinsic diversity. As a result, the existence of ten geological heritage types in the Faiyum Oasis is found. These include palaeontological, palaeogeographical, geomorphological, stratigraphical, sedimentary (merged with mineralogical), hydrological coupled with geochemical, igneous, and economical types. From them, the palaeontological and palaeogeographical types are ranked globally, and the geomorphological and hydrological types are ranked nationally. The other types are either of regional (provincial) or local importance. Some hills and cliffs can serve as viewpoint sites for observation of the local geological landscape. The relative abundance and the intrinsic diversity of the unique geological features vary between low and high. Generally, the concentration of this geological heritage in the Faiyum Oasis permits recognition of the geodiversity hotspot that requires conservation and use for tourism purposes. The protected areas located in the oasis and the existing tourism programs do not offer geoconservation and geotourism activities for the entire hotspot. The possible solution of this problem would be creation of a large geopark similar in its design to the Jeju Island Geopark in South Korea. There are important premises for geotourism development in the Faiyum Oasis and its combination with the archaeological and industrial tourism. Nature conservation failures in this geopark should be avoided; some recommendations are given on

PEM/SPE fuel cell

DOEpatents

Grot, Stephen Andreas

1998-01-01

A PEM/SPE fuel cell including a membrane-electrode assembly (MEA) having a plurality of oriented filament embedded the face thereof for supporting the MEA and conducting current therefrom to contiguous electrode plates.

Searching for Beta-Haemolysin hlb Gene in Staphylococcus pseudintermedius with Species-Specific Primers.

PubMed

Kmieciak, Wioletta; Szewczyk, Eligia M; Ciszewski, Marcin

2016-07-01

The paper presents an analysis of 51 Staphylococcus pseudintermedius clinically isolated strains from humans and from animals. Staphylococcus pseudintermedius strains' ability to produce β-haemolysin was evaluated with phenotypic methods (hot-cold effect, reverse CAMP test). In order to determine the hlb gene presence (coding for β-haemolysin) in a genomic DNA, PCR reactions were conducted with two different pairs of primers: one described in the literature for Staphylococcus aureus and recommended for analysing SIG group staphylococci and newly designed one in CLC Main Workbench software. Only reactions with newly designed primers resulted in product amplification, the presence of which was fully compatible with the results of phenotypic β-haemolysin test. Negative results for S. aureus and S. intermedius reference ATCC strains suggest that after further analysis the fragment of hlb gene amplified with primers described in this study might be included in the process of S. pseudintermedius strains identification.

ASPECTS: an automation-assisted SPE method development system.

PubMed

Li, Ming; Chou, Judy; King, Kristopher W; Yang, Liyu

2013-07-01

A typical conventional SPE method development (MD) process usually involves deciding the chemistry of the sorbent and eluent based on information about the analyte; experimentally preparing and trying out various combinations of adsorption chemistry and elution conditions; quantitatively evaluating the various conditions; and comparing quantitative results from all combination of conditions to select the best condition for method qualification. The second and fourth steps have mostly been performed manually until now. We developed an automation-assisted system that expedites the conventional SPE MD process by automating 99% of the second step, and expedites the fourth step by automatically processing the results data and presenting it to the analyst in a user-friendly format. The automation-assisted SPE MD system greatly saves the manual labor in SPE MD work, prevents analyst errors from causing misinterpretation of quantitative results, and shortens data analysis and interpretation time.

Facile purification and click labeling with 2-[ 18F]fluoroethyl azide using solid phase extraction cartridges

DOE PAGES

Zhou, Dong; Chu, Wenhua; Peng, Xin; ...

2014-11-04

In this paper, a facile method was developed to purify 2-[ 18F]fluoroethyl azide ([ 18F]FEA) using a C18 cartridge and an Oasis® HLB cartridge in series, in which [18F]FEA was exclusively trapped on the HLB cartridge. [ 18F]FEA can be eluted for reactions in solution; alternatively click labeling can be carried out on the HLB cartridge itself by loading an alkyne substrate and copper (I) catalyst dissolved in DMF onto the cartridge. Finally, this solid phase extraction methodology for purification and click labeling with [ 18F]FEA, either in solution or on the cartridge, is safe, simple, reproducible in high yield,more » and compatible with automated synthesis of 18F-labeled PET tracers.« less

Windblown sediment transport and loss in a desert-oasis ecotone in the Tarim Basin.

PubMed

Pi, Huawei; Sharratt, Brenton; Lei, Jiaqiang

2017-08-10

The Tarim Basin is regarded as one of the most highly erodible areas in China. Desert comprises 64% of the land use in the Basin, but the desert-oasis ecotone plays a prominent role in maintaining oasis ecological security and stability. Yet, little is known concerning the magnitude of windblown sediment transport in a desert-oasis ecotone. Therefore, aeolian sediment transport and loss was assessed from a desert-oasis experimental site located near Alaer City in the northwestern Tarim Basin. Sediment transport and factors governing transport were measured during three high wind events in 2012 and four events in 2013. Sediment transport was measured to a height of 10 m using passive aeolian airborne sediment samplers. The mass flux profile over the eroding surface was well represented by the power-law (R 2  > 0.77). Sediment loss from the site ranged from 118 g m -2 for the 20-24Apr 2012 wind event to 2925 g m -2 for the 31Mar-11Apr 2012 event. Suspension accounted for 67.4 to 84.8% of sediment loss across all high wind events. Our results indicate the severity of wind erosion in a desert-oasis ecotone and thus encourage adoption of management practices that will enhance oasis ecological security.

Development and validation of an HPLC method for the simultaneous determination of tocopherols, tocotrienols and carotenoids in cereals after solid-phase extraction.

PubMed

Irakli, Maria N; Samanidou, Victoria F; Papadoyannis, Ioannis N

2011-06-01

The increasing interest in antioxidant properties of cereal and cereal-based products has prompted the development of a simple and reliable HPLC method for the simultaneous determination of important phytochemicals like tocopherols (T), tocotrienols (T3) and carotenoids. Separation was carried out on a Nucleosil 100 C(18) column, 5 μm (250 mm × 4.6 mm) thermostated at 25 °C, using a linear gradient elution system starting with methanol and ending with a mixture of methanol-isopropanol-acetonitrile. All separated compounds including the internal standard (α-tocopherol acetate) were eluted within 16 min and detected by dual detection: fluorescence for tocopherols and tocotrienols at 290 nm excitation and 320 nm emission and UV-vis photodiode array detection for lutein and β-carotene at 450 nm. Detection limits ranged from 0.2 μg/g (β-carotene) to 1.60 μg/g (α-tocopherol). The intra- and inter-assay coefficients of variation were calculated by using cereals with different levels of lipophilic antioxidants. The extraction method involved sample saponification and clean-up by solid-phase extraction (SPE). The extraction recoveries obtained using OASIS HLB SPE cartridges and dichloromethane as eluent were in the range of 90.2-110.1%, with RSD lower than 10%. The method was successfully applied to cereals: durum wheat, bread wheat, rice, barley, oat, rye, corn and triticale. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The classification and assessment of vulnerability of man-land system of oasis city in arid area

NASA Astrophysics Data System (ADS)

Gao, Chao; Lei, Jun; Jin, Fengjun

2013-12-01

Oasis city system is the center of the man-land relationship in arid area and it is the most influential spatial and temporal multiple dynamic system. Oasis city system is not only the largest area where artificial disturbances occur at a regional scale but also the most concentrated area of human activity in arid area. In this study, we developed an applicable and convenient method to assess vulnerability of man-land system of oasis cities with vulnerability indicator system, respectively evaluating the sensitivity, adaptability and vulnerability of the eco-environment system, the economic system and the social system. The results showed that the sensitivity and vulnerability of oasis cities in Xinjiang, China have significant differences while their adaptability does little. In order to find the inherent differences in the vulnerability of oasis cities, triangle methodology has been adopted to divide Xinjiang oasis cities into five types. Some adaptive developing policies specific for individual cities are also proposed based on their vulnerability type and constraining factors.

PEM/SPE fuel cell

DOEpatents

Grot, S.A.

1998-01-13

A PEM/SPE fuel cell is described including a membrane-electrode assembly (MEA) having a plurality of oriented filament embedded the face thereof for supporting the MEA and conducting current therefrom to contiguous electrode plates. 4 figs.

Candidatus Liberibacter asiaticus (CLas)titer in field HLB-exposed commercial citrus cultivars

USDA-ARS?s Scientific Manuscript database

Eight Indian River groves with four or more diverse scions planted in close proximity were surveyed. Twenty trees of each scion in each grove were randomly selected to avoid bias and edge effects and an HLB diagnostic leaf sample was collected from each. CLas 16S rDNA primers were used in qPCR, a...

Geophysical Characterization of Groundwater-Fault Dynamics at San Andreas Oasis

NASA Astrophysics Data System (ADS)

Faherty, D.; Polet, J.; Osborn, S. G.

2017-12-01

The San Andreas Oasis has historically provided a reliable source of fresh water near the northeast margin of the Salton Sea, although since the recent completion of the Coachella Canal Lining Project and persistent drought in California, surface water at the site has begun to disappear. This may be an effect of the canal lining, however, the controls on groundwater are complicated by the presence of the Hidden Springs Fault (HSF), a northeast dipping normal fault that trends near the San Andreas Oasis. Its surface expression is apparent as a lineation against which all plant growth terminates, suggesting that it may form a partial barrier to subsurface groundwater flow. Numerous environmental studies have detailed the chemical evolution of waters resources at San Andreas Spring, although there remains a knowledge gap on the HSF and its relation to groundwater at the site. To better constrain flow paths and characterize groundwater-fault interactions, we have employed resistivity surveys near the surface trace of the HSF to generate profiles of lateral and depth-dependent variations in resistivity. The survey design is comprised of lines installed in Wenner Arrays, using an IRIS Syscal Kid, with 24 electrodes, at a maximum electrode spacing of 5 meters. In addition, we have gathered constraints on the geometry of the HSF using a combination of ground-based magnetic and gravity profiles, conducted with a GEM walking Proton Precession magnetometer and a Lacoste & Romberg gravimeter. Seventeen gravity measurements were acquired across the surface trace of the fault. Preliminary resistivity results depict a shallow conductor localized at the oasis and discontinuous across the HSF. Magnetic data reveal a large contrast in subsurface magnetic susceptibility that appears coincident with the surface trace and trend of the HSF, while gravity data suggests a shallow, relatively high density anomaly centered near the oasis. These data also hint at a second, previously

OASIS: Organics Analyzer for Sampling Icy Surfaces

NASA Technical Reports Server (NTRS)

Getty, S. A.; Dworkin, J. P.; Glavin, D. P.; Martin, M.; Zheng, Y.; Balvin, M.; Southard, A. E.; Ferrance, J.; Malespin, C.

2012-01-01

Liquid chromatography mass spectrometry (LC-MS) is a well established laboratory technique for detecting and analyzing organic molecules. This approach has been especially fruitful in the analysis of nucleobases, amino acids, and establishing chirol ratios [1 -3]. We are developing OASIS, Organics Analyzer for Sampling Icy Surfaces, for future in situ landed missions to astrochemically important icy bodies, such as asteroids, comets, and icy moons. The OASIS design employs a microfabricated, on-chip analytical column to chromatographically separate liquid ana1ytes using known LC stationary phase chemistries. The elution products are then interfaced through electrospray ionization (ESI) and analyzed by a time-of-flight mass spectrometer (TOF-MS). A particular advantage of this design is its suitability for microgravity environments, such as for a primitive small body.

Solid-Phase Extraction (SPE): Principles and Applications in Food Samples.

PubMed

Ötles, Semih; Kartal, Canan

2016-01-01

Solid-Phase Extraction (SPE) is a sample preparation method that is practised on numerous application fields due to its many advantages compared to other traditional methods. SPE was invented as an alternative to liquid/liquid extraction and eliminated multiple disadvantages, such as usage of large amount of solvent, extended operation time/procedure steps, potential sources of error, and high cost. Moreover, SPE can be plied to the samples combined with other analytical methods and sample preparation techniques optionally. SPE technique is a useful tool for many purposes through its versatility. Isolation, concentration, purification and clean-up are the main approaches in the practices of this method. Food structures represent a complicated matrix and can be formed into different physical stages, such as solid, viscous or liquid. Therefore, sample preparation step particularly has an important role for the determination of specific compounds in foods. SPE offers many opportunities not only for analysis of a large diversity of food samples but also for optimization and advances. This review aims to provide a comprehensive overview on basic principles of SPE and its applications for many analytes in food matrix.

Spatio-temporal analysis of an HLB epidemic in Florida and implications for spread.

USDA-ARS?s Scientific Manuscript database

Data for Huanglongbing (HLB) epidemics was collected during 5 assessment dates over a 2-year period from 11, 4-ha commercial citrus blocks in Florida. Data were analyzed for regional spatial characteristics via Ripley’s K analyses. Data were fitted to the logistic and Gompertz temporal models, the...

OASIS: PARAMETER ESTIMATION SYSTEM FOR AQUIFER RESTORATION MODELS, USER'S MANUAL VERSION 2.0

EPA Science Inventory

OASIS, a decision support system for ground water contaminant modeling, has been developed for the CPA by Rice University, through the National Center for Ground Water Research. As a decision support system, OASIS was designed to provide a set of tools which will help scientists ...

Analysis and Simulations of Near-Field Ground Motion from Source Physics Experiments (spe)

NASA Astrophysics Data System (ADS)

Vorobiev, O.; Xu, H.; Lomov, I.; Herbold, E. B.; Glenn, L. A.; Antoun, T.

2012-12-01

This work is focused on analysis of near-field measurements (up to 50-70 m from the source) recorded during Source Physics Experiments SPE1, SPE2 and SPE3 in a granitic formation (the Climax Stock) at the Nevada National Security Site (NNSS). The explosive source used in these experiments is a sensitized heavy ANFO (SHANFO) with a well characterized equation of state. The first event, SPE1, had a yield of 0.1 ton, and was detonated at a 55 m depth of burial in a spherical cavity of about 0.3 m radius. SPE2 and SPE3 had an explosive yield of 1 ton, and they were both detonated in the same cavity at a depth of burial of 45 meters. One of the main goals of these experiments was to investigate the possible mechanisms of shear wave generation in the nonlinear source region. Another objective, relating specifically to the SPE2-SPE3 sequence, was to investigate the effect of damage from one explosion on the response of the medium to a second explosion of the same yield and at the same location as the first explosion. Comparison of the results from SPE2 and SPE3 show some interesting trends. . At the shot level, and at deeper locations, the data from SPE3 seem to agree quite well with SPE2 data, indicating that damage from SPE2 had little to no effect on the response of the medium at these locations. On the other hand, SPE3 data consistently show delay in arrival times as well as reduced wave amplitudes both at 50 ft (16 m) depth and at the ground surface, indicating that above the shot horizon damage from SPE2 had a perceptible effect on the SPE3 near field motions. The quality of the near field data at some gages from the SPE1 and SPE2 events is somewhat questionable, with orientation uncertainties making it difficult to ascertain with confidence the extent to which shear wave generation in the source region affected near field motions. New gages were strategically added to the SPE3 test bed to provide the data needed to address this issue and verify previous

A novel molecular diagnostic tool for improved sensitivity and reliability detection of “Candidatus Liberibacter asiaticus”, bacterium associated with huanglongbing (HLB) bacterium Candidatus Liberibacter.

USDA-ARS?s Scientific Manuscript database

Sensitive and accurate detection is a prerequisite for efficient management and regulatory responses to prevent the introduction and spread of HLB-associated “Candidatus Liberibacter species to unaffected areas. To improve the current detection limit of HLB-associated “Ca. Liberibacter” spp, we deve...

Horticulture take-home messages. Grower Day Summary: 2011 International HLB Meeting, Orlando, Florida

USDA-ARS?s Scientific Manuscript database

The 2nd International Research Conference on Huanglongbing covered 3 full days, with 400 participants from 20 countries. There were 75 oral presentations, 96 posters, and I took 20 pages of notes. Urgency of HLB as a threat to citrus production and the engine of substantial grower investment has fu...

Active taste compounds in juice from oranges symptomatic for Huanglongbing (HLB) citrus greening disease

USDA-ARS?s Scientific Manuscript database

Citrus greening disease, also known as Huanglongbing (HLB), compromises the quality of citrus fruit and juice, causing increased bitterness, metallic taste, astringency and a burning mouthfeel. The chemical basis responsible for these changes remains largely unknown other than the roles of the bitte...

Visible/near-infrared spectroscopy for discrimination of HLB-infected citrus leaves from healthy leaves

USDA-ARS?s Scientific Manuscript database

Researchers have used various hyperspectral systems, covering several areas of the electromagnetic spectrum to investigate all types of disease/plant interactions. The purpose of this research was to investigate using visible and near-infrared (400-1100nm) spectroscopy to differentiate HLB infected...

Simultaneous determination of 15 phenolic constituents of Chinese black rice wine by HPLC-MS/MS with SPE.

PubMed

Wang, Yutang; Liu, Yuanyuan; Xiao, Chunxia; Liu, Laping; Hao, Miao; Wang, Jianguo; Liu, Xuebo

2014-06-01

This study established a new method for quantitative and qualitative determination of certain components in black rice wine, a traditional Chinese brewed wine. Specifically, we combined solid-phase extraction and high-performance liquid chromatography (HPLC) with triple quadrupole mass spectrometry (MS/MS) to determine 8 phenolic acids, 3 flavonols, and 4 anthocyanins in black rice wine. First, we clean samples with OASIS HLB cartridges and optimized extraction parameters. Next, we performed separation on a SHIM-PACK XR-ODS column (I.D. 3.0 mm × 75 mm, 2.2 μm particle size) with a gradient elution of 50% aqueous acetonitrile (V/V) and water, both containing 0.2% formic acid. We used multiple-reaction monitoring scanning for quantification, with switching electrospray ion source polarity between positive and negative modes in a single chromatographic run. We detected 15 phenolic compounds properly within 38 min under optimized conditions. Limits of detection ranged from 0.008 to 0.030 mg/L, and average recoveries ranged from 60.8 to 103.1% with relative standard deviation ≤8.6%. We validated the method and found it to be sensitive and reliable for quantifying phenolic compounds in rice wine matrices. This study developed a new, reliable HPLC-MS/MS method for simultaneous determination of 15 bioactive components in black rice wine. This method was validated and found to be sensitive and reliable for quantifying phenolic compounds in rice wine. © 2014 Institute of Food Technologists®

Determination of novel brominated flame retardants and polybrominated diphenyl ethers in serum using gas chromatography-mass spectrometry with two simplified sample preparation procedures.

PubMed

Gao, Le; Li, Jian; Wu, Yandan; Yu, Miaohao; Chen, Tian; Shi, Zhixiong; Zhou, Xianqing; Sun, Zhiwei

2016-11-01

Two simple and efficient pretreatment procedures have been developed for the simultaneous extraction and cleanup of six novel brominated flame retardants (NBFRs) and eight common polybrominated diphenyl ethers (PBDEs) in human serum. The first sample pretreatment procedure was a quick, easy, cheap, effective, rugged, and safe (QuEChERS)-based approach. An acetone/hexane mixture was employed to isolate the lipid and analytes from the serum with a combination of MgSO 4 and NaCl, followed by a dispersive solid-phase extraction (d-SPE) step using C18 particles as a sorbent. The second sample pretreatment procedure was based on solid-phase extraction. The sample extraction and cleanup were conducted directly on an Oasis HLB SPE column using 5 % aqueous isopropanol, concentrated sulfuric acid, and 10 % aqueous methanol, followed by elution with dichloromethane. The NBFRs and PBDEs were then detected using gas chromatography-negative chemical ionization mass spectrometry (GC-NCI MS). The methods were assessed for repeatability, accuracy, selectivity, limits of detection (LODs), and linearity. The results of spike recovery experiments in fetal bovine serum showed that average recoveries ranged from 77.9 % to 128.8 % with relative standard deviations (RSDs) from 0.73 % to 12.37 % for most of the analytes. The LODs for the analytes in fetal bovine serum ranged from 0.3 to 50.8 pg/mL except for decabromodiphenyl ethane. The proposed method was successfully applied to the determination of the 14 brominated flame retardants in human serum. The two pretreatment procedures described here are simple, accurate, and precise, and are suitable for the routine analysis of human serum. Graphical Abstract Workflow of a QuEChERS-based approach (top) and an SPE-based approach (bottom) for the detection of PBDEs and NBFRs in serum.

Screening method for the determination of tetracyclines and fluoroquinolones in animal drinking water by liquid chromatography with diode array detector.

PubMed

Patyra, E; Kowalczyk, E; Grelik, A; Przeniosło-Siwczyńska, M; Kwiatek, K

2015-01-01

A liquid chromatography - diode array detector (HPLC-DAD) procedure has been developed for the determination of oxytetracycline (OTC), tetracycline (TC), chlorotetracycline (CTC), doxycycline (DC), enrofloxacin (ENR), ciprofloxacin (CIP), sarafloxacin (SAR) and flumequine (FLU) residues in animal drinking water. This method was applied to animal drinking water. Solid-phase extraction (SPE) clean-up on an Oasis HLB cartridge allowed an extract suitable for liquid chromatographic analysis to be obtained. Chromatographic separation was carried out on a C18 analytical column, using gradient elution with 0.1% trifluoroacetic acid - acetonitrile - methanol at 30°C. The flow-rate was 0.7 mL/min and the eluate was analysed at 330 nm. The whole procedure was evaluated according to the requirements of the Commission Decision 2002/657/EC, determining specificity, decision limit (CCα), detection capacity (CCβ), limit of detection (LOD), limit of quantification (LOQ), precision and accuracy during validation of the method. The recoveries of TCs and FQs from spiked samples at the levels of 10, 100 and 1000 μg/L were higher than 82%. The developed method based on HPLC-DAD has been applied for the determination of four tetracyclines and four fluoroquinolones in animal drinking water samples.

Multiclass analysis of antibiotic residues in honey by ultraperformance liquid chromatography-tandem mass spectrometry.

PubMed

Vidal, Jose Luis Martínez; Aguilera-Luiz, María Del Mar; Romero-González, Roberto; Frenich, Antonia Garrido

2009-03-11

A method has been developed and validated for the simultaneous analysis of different veterinary drug residues (macrolides, tetracyclines, quinolones, and sulfonamides) in honey. Honey samples were dissolved with Na(2)EDTA, and veterinary residues were extracted from the supernatant by solid-phase extraction (SPE), using OASIS HLB cartridges. The separation and determination was carried out by ultraperformance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS), using an electrospay ionization source (ESI) in positive mode. Data acquisition under MS/MS was achieved by applying multiple reaction monitoring (MRM) of two ion transitions per compound to provide a high degree of sensitivity and specificity. The method was validated, and mean recoveries were evaluated at three concentration levels (10, 50, and 100 microg/kg), ranging from 70 to 120% except for doxycycline, erythromycin, and tylmicosin with recovery higher than 50% at the three levels assayed. Relative standard deviations (RSDs) of the recoveries were less than 20% within the intraday precision and less than 25% within the interday precision. The limits of quantification (LOQs) were always lower than 4 microg/kg. The developed procedure was applied to 16 honey samples, and erythromycin, sarafloxacin, and tylosin were found in a few samples.

SPE propulsion electrolyzer for NASA's integrated propulsion test article

NASA Technical Reports Server (NTRS)

1991-01-01

Hamilton Standard has delivered a 3000 PSI SPE Propulsion Electrolyzer Stack and Special Test Fixture to the NASA Lyndon B. Johnson Space Center (JSC) Integrated Propulsion Test Article (IPTA) program in June 1990, per contract NAS9-18030. This prototype unit demonstrates the feasibility of SPE-high pressure water electrolysis for future space applications such as Space Station propulsion and Lunar/Mars energy storage. The SPE-Propulsion Electrolyzer has met or exceeded all IPTA program goals. It continues to function as the primary hydrogen and oxygen source for the IPTA test bed at the NASA/JSC Propulsion and Power Division Thermochemical Test Branch.

The oasis effect and summer temperature rise in arid regions - case study in Tarim Basin

PubMed Central

Hao, Xingming; Li, Weihong; Deng, Haijun

2016-01-01

This study revealed the influence of the oasis effect on summer temperatures based on MODIS Land Surface Temperature (LST) and meteorological data. The results showed that the oasis effect occurs primarily in the summer. For a single oasis, the maximum oasis cold island intensity based on LST (OCILST) was 3.82 °C and the minimum value was 2.32 °C. In terms of the annual change in OCILST, the mean value of all oases ranged from 2.47 °C to 3.56 °C from 2001 to 2013. Net radiation (Rn) can be used as a key predictor of OCILST and OCItemperature (OCI based on air temperature). On this basis, we reconstructed a long time series (1961–2014) of OCItemperature and Tbase(air temperature without the disturbance of oasis effect). Our results indicated that the reason for the increase in the observed temperatures was the significant decrease in the OCItemperature over the past 50 years. In arid regions, the data recorded in weather stations not only underestimated the mean temperature of the entire study area but also overestimated the increasing trend of the temperature. These discrepancies are due to the limitations in the spatial distribution of weather stations and the disturbance caused by the oasis effect. PMID:27739500

STS-26 Discovery, OV-103, OASIS equipment is mounted in payload bay (PLB)

NASA Image and Video Library

1988-04-18

S88-37764 (18 April 1988) --- OASIS, instrumentation which will record the environment experienced by Discovery during the STS-26 Space Shuttle mission, is lowered into position for attachment to the orbiter's aft port sill. Instrumentation sensors in the payload bay which are connected to the tape recorder module will document a variety of environmental measurements during various phases of the flight including temperature, pressure, vibration, sounds, acceleration, stress, and strain. OASIS will also record data during the Flight Readiness Firing. NASA is flying OASIS aboard Discovery in support of the Inertial Upper Stage (IUS) program office of the Air Force Space Division. The system was developed by Lockheed under a NASA contract, funded by the Air Force.

Determination of fluoroquinolones in fish tissues, biological fluids, and environmental waters by liquid chromatography tandem mass spectrometry.

PubMed

Ziarrusta, Haizea; Val, Nahia; Dominguez, Haizea; Mijangos, Leire; Prieto, Ailette; Usobiaga, Aresatz; Etxebarria, Nestor; Zuloaga, Olatz; Olivares, Maitane

2017-11-01

This work describes the optimization, validation, and application in real samples of accurate and precise analytical methods to determine ten fluoroquinolones (FQs) (norfloxacin, enoxacin, pefloxacin, ofloxacin, levofloxacin, ciprofloxacin, danofloxacin, lomefloxacin, enrofloxacin, and sparfloxacin) in different environmental matrices, such as water (estuarine, seawater, and wastewater treatment plant effluent), fish tissues (muscle and liver), and fish biofluids (plasma and bile). The analysis step performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was fully optimized to improve the separation and detection steps. The extraction of analytes from fish tissues was accomplished using focused ultrasound solid-liquid extraction using methanol/acetic acid (95:5 v/v) as extractant. The preconcentration and clean-up steps were optimized in terms of extraction efficiency and cleanliness and the best strategy for each matrix was selected: (i) Oasis HLB for seawater and muscle, (ii) liquid-liquid extraction combined with Oasis HLB for the lipid-rich liver, (iii) the combination of Evolute-WAX and Oasis HLB for estuarine water and wastewater treatment plant effluent, and (iv) molecular imprinted polymers for biofluids. The methods afforded satisfactory apparent recoveries (80-126%) and repeatability (RSD < 15%), except for sparfloxacin, which showed a lack of correction with the available isotopically labeled surrogates ([ 2 H 8 ]-ciprofloxacin and [ 2 H 5 ]-enrofloxacin). Ciprofloxacin, norfloxacin, and ofloxacin were detected in both water and fish liver samples from the Biscay Coast at concentrations up to 278 ng/L and 4 ng/g, respectively. To the best of our knowledge, this work is one of the few analyzing up to ten FQs and in so many fish tissues and biofluids. Graphical abstract Determination of fluoroquinolones in different environmental matrices, such as water (estuarine, seawater, and wastewater treatment plant effluent), fish tissues (muscle

SPE (tm) regenerative hydrogen/oxygen fuel cells for extraterrestrial surface and microgravity applications

NASA Technical Reports Server (NTRS)

Mcelroy, J. F.

1990-01-01

Viewgraphs on SPE regenerative hydrogen/oxygen fuel cells for extraterrestrial surface and microgravity applications are presented. Topics covered include: hydrogen-oxygen regenerative fuel cell energy storage system; electrochemical cell reactions; SPE cell voltage stability; passive water removal SPE fuel cell; fuel cell performance; SPE water electrolyzers; hydrophobic oxygen phase separator; hydrophilic/electrochemical hydrogen phase separator; and unitized regenerative fuel cell.

The Martian Oasis Detector

NASA Astrophysics Data System (ADS)

Smith, P. H.; tomasko, M. G.; McEwen, A.; Rice, J.

2000-07-01

The next phase of unmanned Mars missions paves the way for astronauts to land on the surface of Mars. There are lessons to be learned from the unmanned precursor missions to the Moon and the Apollo lunar surface expeditions. These unmanned missions (Ranger, Lunar Orbiter, and Surveyor) provided the following valuable information, useful from both a scientific and engineering perspective, which was required to prepare the way for the manned exploration of the lunar surface: (1) high resolution imagery instrumental to Apollo landing site selection also tremendously advanced the state of Nearside and Farside regional geology; (2) demonstrated precision landing (less than two kilometers from target) and soft landing capability; (3) established that the surface had sufficient bearing strength to support a spacecraft; and (4) examination of the chemical composition and mechanical properties of the surface. The search for extinct or extant life on Mars will follow the water. However, geomorphic studies have shown that Mars has had liquid water on its surface throughout its geologic history. A cornucopia of potential landing sites with water histories (lakes, floodplains, oceans, deltas, hydrothermal regions) presently exist. How will we narrow down site selection and increase the likelihood of finding the signs of life? One way to do this is to identify 'Martian oases.' It is known that the Martian surface is often highly fractured and some areas have karst structures that support underground caves. Much of the water that formed the channels and valley networks is thought to be frozen underground. All that is needed to create the potential for liquid water is a near surface source of heat; recent lava flows and Martian meteorites attest to the potential for volcanic activity. If we can locate even one spot where fracturing, ice, and underground heat are co-located then we have the potential for an oasis. Such a discovery could truly excite the imaginations of both the

Toward Semantic Interoperability in Home Health Care: Formally Representing OASIS Items for Integration into a Concept-oriented Terminology

PubMed Central

Choi, Jeungok; Jenkins, Melinda L.; Cimino, James J.; White, Thomas M.; Bakken, Suzanne

2005-01-01

Objective: The authors aimed to (1) formally represent OASIS-B1 concepts using the Logical Observation Identifiers, Names, and Codes (LOINC) semantic structure; (2) demonstrate integration of OASIS-B1 concepts into a concept-oriented terminology, the Medical Entities Dictionary (MED); (3) examine potential hierarchical structures within LOINC among OASIS-B1 and other nursing terms; and (4) illustrate a Web-based implementation for OASIS-B1 data entry using Dialogix, a software tool with a set of functions that supports complex data entry. Design and Measurements: Two hundred nine OASIS-B1 items were dissected into the six elements of the LOINC semantic structure and then integrated into the MED hierarchy. Each OASIS-B1 term was matched to LOINC-coded nursing terms, Home Health Care Classification, the Omaha System, and the Sign and Symptom Check-List for Persons with HIV, and the extent of the match was judged based on a scale of 0 (no match) to 4 (exact match). OASIS-B1 terms were implemented as a Web-based survey using Dialogix. Results: Of 209 terms, 204 were successfully dissected into the elements of the LOINC semantics structure and integrated into the MED with minor revisions of MED semantics. One hundred fifty-one OASIS-B1 terms were mapped to one or more of the LOINC-coded nursing terms. Conclusion: The LOINC semantic structure offers a standard way to add home health care data to a comprehensive patient record to facilitate data sharing for monitoring outcomes across sites and to further terminology management, decision support, and accurate information retrieval for evidence-based practice. The cross-mapping results support the possibility of a hierarchical structure of the OASIS-B1 concepts within nursing terminologies in the LOINC database. PMID:15802480

Toward semantic interoperability in home health care: formally representing OASIS items for integration into a concept-oriented terminology.

PubMed

Choi, Jeungok; Jenkins, Melinda L; Cimino, James J; White, Thomas M; Bakken, Suzanne

2005-01-01

The authors aimed to (1) formally represent OASIS-B1 concepts using the Logical Observation Identifiers, Names, and Codes (LOINC) semantic structure; (2) demonstrate integration of OASIS-B1 concepts into a concept-oriented terminology, the Medical Entities Dictionary (MED); (3) examine potential hierarchical structures within LOINC among OASIS-B1 and other nursing terms; and (4) illustrate a Web-based implementation for OASIS-B1 data entry using Dialogix, a software tool with a set of functions that supports complex data entry. Two hundred nine OASIS-B1 items were dissected into the six elements of the LOINC semantic structure and then integrated into the MED hierarchy. Each OASIS-B1 term was matched to LOINC-coded nursing terms, Home Health Care Classification, the Omaha System, and the Sign and Symptom Check-List for Persons with HIV, and the extent of the match was judged based on a scale of 0 (no match) to 4 (exact match). OASIS-B1 terms were implemented as a Web-based survey using Dialogix. Of 209 terms, 204 were successfully dissected into the elements of the LOINC semantics structure and integrated into the MED with minor revisions of MED semantics. One hundred fifty-one OASIS-B1 terms were mapped to one or more of the LOINC-coded nursing terms. The LOINC semantic structure offers a standard way to add home health care data to a comprehensive patient record to facilitate data sharing for monitoring outcomes across sites and to further terminology management, decision support, and accurate information retrieval for evidence-based practice. The cross-mapping results support the possibility of a hierarchical structure of the OASIS-B1 concepts within nursing terminologies in the LOINC database.

SPE in Solar Cycle 24 : Flare and CME characteristic

NASA Astrophysics Data System (ADS)

Neflia, Neflia

SPE is one of the most severe hazards in the space environment. Such events, tend to occur during periods of intense solar activity, and can lead to high radiation doses in short time intervals. The proton enhancements produced by these solar events may last several days and are very hard to predict in advance and they also can cause harm to both satellite and human in space. The most significant sources of proton in the interplanetary medium are both solar flares and interplanetary shocks driven by coronal mass ejections (CMEs). In this study, I try to find the characteristic of Flare and CME that can cause the proton events in interplanetary medium. For my preliminary study, I will search flare characteristic such as class and position as an SPE causes. I also did the research with CME characteristic such as Angular Width (AW) and linier velocity. During solar cycle 24, the solar activity remain very low with several large flare and Halo CME. This low activity also occur on solar proton events in interplanetary medium. From January 2009 to May 2013, there are 25 SPEs with flux range from 12 - 6530 sfu (10 MeV). The solar flare during these events varies from C to X- class flare. From 27 X-class flare that occur during 2009 - May 2013, only 7 flares cause the SPE. Most of active region location are at solar Western Hemisphere (16/25). only 24 from 139 halo CME (AW=360) cause SPE. Although the probability of SPE from all flare and CME during this range of time is small but they have 3 common characteristics, ie, most of the SPE have active region position at Solar Western Hemisphere, the CME have AW=360 and they have a high linier velocity.

Imaging of VMAT2 binding sites in the brain by (18)F-AV-133: the effect of a pseudo-carrier.

PubMed

Zhu, Lin; Qiao, Hongwen; Lieberman, Brian P; Wu, Jingxiao; Liu, Yajing; Pan, Zhongyun; Ploessl, Karl; Choi, Seok Rye; Chan, Piu; Kung, Hank F

2012-10-01

Recently, 9-[(18)F]fluoropropyl-(+)-dihydrotetrabenazine ((18)F-AV-133) was reported as a new vesicular monoamine transporter (VMAT2) imaging agent for diagnosis of Parkinson's disease (PD). To shorten the preparation of (18)F-AV-133 and to make it more widely available, we evaluated a simple, rapid purification with a solid-phase extraction method (SPE) using an Oasis HLB cartridge instead of high pressure liquid chromatography (HPLC). The SPE method produced doses containing a pseudo-carrier, 9-hydroxypropyl-(+)-dihydrotetrabenazine (AV-149). To test the possible side effects of this pseudo-carrier, comparative dynamic PET scans of the brains of normal monkeys (2 each) and uni-laterally 6-OH-dopamine-lesioned PD monkeys (2 each) were performed using (18)F-AV-133 doses prepared by either SPE (containing pseudo-carrier) or HPLC (containing no pseudo-carrier). Autoradiographs of post mortem monkey brain sections were evaluated to confirm the relative (18)F-AV-133 uptake in the PD monkey brains and the effects of the pseudo-carrier on VMAT2 binding. The radiochemical purity of the (18)F-AV-133, whether prepared by SPE or by HPLC, was excellent (>99%). PET scans of normal and PD monkey brains showed an expected reduction of VMAT2 in the lesioned areas of the striatum. It was not affected by the presence of the pseudo-carrier, AV-149 (maximally 250 μg/dose). The reduced uptake in the striatum of the lesioned monkey brains was confirmed by autoradiography. Ex vivo inhibition studies of (18)F-AV-133 binding in rat brains, conducted with increasing amounts of AV-149, suggested that at the highest concentration (3.5mg/kg) the VMAT2 binding in the striatum was only moderately blocked (20% reduction). The pseudo-carrier, AV-149, did not affect the (18)F-AV-133/PET imaging of VMAT2 binding sites in normal or uni-laterally lesioned monkey brains. The new streamlined SPE purification method will enable (18)F-AV-133 to be widely available for routine clinical application in

Development and validation of a solid phase extraction sample cleanup procedure for the recovery of trace levels of nitro-organic explosives in soil.

PubMed

Thomas, Jennifer L; Donnelly, Christopher C; Lloyd, Erin W; Mothershead, Robert F; Miller, Mark L

2018-03-01

An improved cleanup method has been developed for the recovery of trace levels of 12 nitro-organic explosives in soil, which is important not only for the forensic community, but also has environmental implications. A wide variety of explosives or explosive-related compounds were evaluated, including nitramines, nitrate esters, nitroaromatics, and a nitroalkane. Fortified soil samples were extracted with acetone, processed via solid phase extraction (SPE), and then analyzed by gas chromatography with electron capture detection. The following three SPE sorbents in cartridge format were compared: Empore™ SDB-XC, Oasis ® HLB, and Bond Elut NEXUS cartridges. The NEXUS cartridges provided the best overall recoveries for the 12 explosives in potting soil (average 48%) and the fastest processing times (<30min). It also rejected matrix components from spent motor oil on potting soil. The SPE method was validated by assessing limit of detection (LOD), processed sample stability, and interferences. All 12 compounds were detectable at 0.02μg explosive/gram of soil or lower in the three matrices tested (potting soil, sand, and loam) over three days. Seven explosives were stable up to seven days at 2μg/g and three were stable at 0.2μg/g, both in processed loam, which was the most challenging matrix. In the interference study, five interferences above the determined LOD for soil were detected in matrices collected across the United States and in purchased all-purpose sand, potting soil, and loam. This represented a 3.2% false positive rate for the 13 matrices processed by the screening method for interferences. The reported SPE cleanup method provides a fast and simple extraction process for separating organic explosives from matrix components, facilitating sample throughput and reducing instrument maintenance. In addition, a comparison study of the validated SPE method versus conventional syringe filtration was completed and highlighted the benefits of sample cleanup for

Windblown sediment transport and loss in a desert–oasis ecotone in the Tarim Basin

USDA-ARS?s Scientific Manuscript database

The Tarim Basin is regarded as one of the most highly erodible areas in China. Desert comprises 64% of the land use in the Basin, but the desert–oasis ecotone plays a prominent role in maintaining oasis ecological security and stability. Yet, little is known concerning the magnitude of windblown sed...

Combined solid-phase extraction and gas chromatography-mass spectrometry used for determination of chloropropanols in water.

PubMed

González, Paula; Racamonde, Inés; Carro, Antonia M; Lorenzo, Rosa A

2011-10-01

A sensitive and rapid derivatization method for the simultaneous determination of 1,3-dichloro-2-propanol (1,3-DCP) and 3-chloropropane-1,2-diol (3-MCPD) in water samples has been developed. The aim was to research the optimal conditions of the derivatization process for two selected reagents. A central composite design was used to determine the influence of derivatization time, derivatization temperature and reagent volume. A global desirability function was applied for multi-response optimization. The analysis was performed by gas chromatography-mass spectrometry. During the optimization of the extraction procedure, four different types of solid-phase extraction (SPE) columns were tested. It was demonstrated that the Oasis HLB cartridge produced the best recoveries of the target analytes. The pH value and the salinity were investigated using a Doehlert design. The best results for the SPE of both analytes were obtained with 1.5 g of NaCl and pH 6. The proposed method provides high sensitivity, good linearity (R(2)≥0.999) and repeatability (relative standard deviations % between 2.9 and 3.4%). Limits of detection and quantification were in the range of 1.4-11.2 ng/mL and 4.8-34.5 ng/mL, respectively. Recoveries obtained for water samples were ca. 100% for 1,3-DCP and 3-MCPD. The method has been successfully applied to the analysis of different samples including commercially bottled water, an influent and effluent sewage. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... operating the OASIS system: (a) Establish and maintain an OASIS database. The State agency or other entity designated by CMS must— (1) Use a standard system developed or approved by CMS to collect, store, and analyze..., system back-up, and monitoring the status of the database; and (3) Obtain CMS approval before modifying...

The Skateboard Factory: Curriculum by Design--Oasis Skateboard Factory Q&A with Craig Morrison

ERIC Educational Resources Information Center

Pearson, George

2012-01-01

Since its opening three years ago, Oasis Skateboard Factory (OSF), founded by teacher Craig Morrison, has attracted considerable media exposure and received a Ken Spencer Award from the CEA for its innovative program. OSF is one of three programs offered by Oasis Alternative Secondary School, one of 22 alternative secondary schools of the Toronto…

Oasis Connections: Results from an Evaluation Study

ERIC Educational Resources Information Center

Czaja, Sara J.; Lee, Chin Chin; Branham, Janice; Remis, Peggy

2012-01-01

Purpose of the Study: The objectives of this study were to evaluate a community-based basic computer and Internet training program designed for older adults, provide recommendations for program refinement, and gather preliminary information on program sustainability. Design and Methods: The program was developed by the OASIS Institute, a nonprofit…

SpeCond: a method to detect condition-specific gene expression

PubMed Central

2011-01-01

Transcriptomic studies routinely measure expression levels across numerous conditions. These datasets allow identification of genes that are specifically expressed in a small number of conditions. However, there are currently no statistically robust methods for identifying such genes. Here we present SpeCond, a method to detect condition-specific genes that outperforms alternative approaches. We apply the method to a dataset of 32 human tissues to determine 2,673 specifically expressed genes. An implementation of SpeCond is freely available as a Bioconductor package at http://www.bioconductor.org/packages/release/bioc/html/SpeCond.html. PMID:22008066

Volatiles in the Desert: Subtle Remote-sensing Signatures of the Dakhleh Oasis Catastrophic Event, Western Desert, Egypt

NASA Technical Reports Server (NTRS)

Haldemann, A. F. C.; Kleindienst, M. R.; Churcher, C. S.; Smith, J. R.; Schwarcz, H. P.; Osinski, G.

2005-01-01

Over the past decade members of the Dakhleh Oasis Project have studied enigmatic signatures in the Pleistocene geologic record of portions of the Dakhleh oasis and palaeo-oasis in Egypt's Western Desert [1,2]. In particular, Si-Ca-Al rich glass melt (Dakhleh Glass, Fig. 1) points to a catastrophic event between c.100,000-200,000 years ago [3] in this well-studied African savannah and freshwater lake Middle Stone Age environment [4,5].

RELAP5 posttest calculation of IAEA-SPE-4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petelin, S.; Mavko, B.; Parzer, I.

The International Atomic Energy Agency`s Fourth Standard Problem Exercise (IAEA-SPE-4) was performed at the PMK-2 facility. The PMK-2 facility is designed to study processes following small- and medium-size breaks in the primary system and natural circulation in VVER-440 plants. The IAEA-SPE-4 experiment represents a cold-leg side small break, similar to the IAEA-SPE-2, with the exception of the high-pressure safety injection being unavailable, and the secondary side bleed and feed initiation. The break valve was located at the dead end of a vertical downcomer, which in fact simulates a break in the reactor vessel itself, and should be unlikely to happenmore » in a real nuclear power plant (NPP). Three different RELAP5 code versions were used for the transient simulation in order to assess the calculations with test results.« less

Implementation of the RCOG guidelines for prevention of obstetric anal sphincter injuries (OASIS) at two London Hospitals: A time series analysis.

PubMed

Mohiudin, Henna; Ali, Sajjad; Pisal, Pradyna N; Villar, Rose

2018-05-01

To audit the impact of implementation of the RCOG guidelines for prevention of Obstetric anal sphincter injuries (OASIS) by introducing antenatal perineal massage, manual perineal protection, and cutting episiotomies at 60° to the midline at the time of crowning. Time series analysis; Setting - Two London teaching hospitals; Royal Free London (RFL) and Barnet; Population or Sample - All nulliparous women undergoing vaginal birth; Methods - Training was provided for above techniques. EPISCISSORS-60 were introduced to perform 60° episiotomies. Data were extracted from maternity databases and dashboards; Main Outcome Measures - OASIS rates before and after implementation. Data from 2566 births were analysed. In operative vaginal deliveries (OVD), OASIS declined from 9.6% to 2% (p = 0.001) at Barnet and from 5.6% to 4.2% (p = 0.4) at RFL. OASIS reduced in nulliparous OVD's given episiotomies from 6.3% in the 'before' period to 0.6% in the 'after' period [p = 0.01] at Barnet. Before introduction of the EPISCISSORS-60, OASIS rate was 6.3% with episiotomies and 30% without episiotomies (p = 0.000). After introduction of the EPISCISSORS-60, OASIS rate was 0.63% with episiotomies v 16% without episiotomies (p = 0.000) at Barnet. At RFL, OASIS rate was 2.6% with episiotomies, and 42% without episiotomy (p = 0.000). In SVD's at Barnet, OASIS declined from 6.6% before to 0% after (p = 0.000) in women given episiotomies while it declined from 5.4% to 3% (p = 0.12) in those not given episiotomies. After introduction of the EPISCISSORS-60, OASIS was 0% in women with episiotomies and 3% in those without episiotomies (p = 0.04). In SVD's at RFL, OASIS was 0% in women given episiotomy v 4.7% without episiotomy (p = 0.03). Deliveries with EPISCISSORS-60 episiotomies had lesser OASIS than those without episiotomies in both nulliparous OVD's and SVD's. OASIS was lower with EPISCISSORS-60 episiotomies than those with eyeballed episiotomies

[Study on ecological risk assessment technology of fluoride pollution from arid oasis soil].

PubMed

Xue, Su-Yin; Li, Ping; Wang, Sheng-Li; Nan, Zhong-Ren

2014-03-01

According to translocation regulation of fluoride in the typical oasis soil-plant system under field, an ecological risk assessment model of fluoride was established, and this model was used to assess ecological risk to fluoride pollution from suburban oasis soils in Baiyin City, which was specifically expressed with the potential ecological risk of bioavailability (ER(bc)) model to assess ecological risk of fluoride pollution in oasis regions. Results showed that the ecological risk indices of fluoride pollution from this region were 1.37-24.81, the level of risk at most sites was high to very high, the average ecological risk index was 11.28, belonged to very high risk. This indicated that in the suburb soil of Baiyin City needs to be concerned about the remediation of fluoride pollution.

Data Release Report for Source Physics Experiments 2 and 3 (SPE-2 and SPE-3) Nevada National Security Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Townsend, Margaret; Obi, Curtis

2015-04-30

The second Source Physics Experiment shot (SPE-2) was conducted in Nevada on October 25, 2011, at 1900:00.011623 Greenwich Mean Time (GMT). The explosive source was 997 kilograms (kg) trinitrotoluene (TNT) equivalent of sensitized heavy ammonium fuel oil (SHANFO) detonated at a depth of 45.7 meters (m). The third Source Physics Experiment shot (SPE-3) was conducted in Nevada on July 24, 2012, at 1800:00.44835 GMT. The explosive source was 905 kg TNT equivalent of SHANFO detonated at a depth of 45.8 m. Both shots were recorded by an extensive set of instrumentation that includes sensors both at near-field (less than 100more » m) and far-field (100 m or greater) distances. The near-field instruments consisted of three-component accelerometers deployed in boreholes at 15, 46, and 55 m depths around the shot and a set of single-component vertical accelerometers on the surface. The far-field network was composed of a variety of seismic and acoustic sensors, including short-period geophones, broadband seismometers, three-component accelerometers, and rotational seismometers at distances of 100 m to 25 kilometers. This report coincides with the release of these data for analysts and organizations that are not participants in this program. This report describes the second and third Source Physics Experiment shots and the various types of near-field and farfield data that are available.This revised document includes reports on baseline shift corrections for the SPE-2 and SPE-3 shots that were missing from the original January 2015 version.« less

A graft-based chemotherapy method for screening effective molecules and rescuing Huanglongbing (HLB)-affected citrus plants

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB), the most devastating disease of citrus worldwide, is associated with three species of fastidious and phloem-limited a-Proteobacteria in the genus of ‘Candidatus Liberibacter’. We previously reported a regeneration-based chemical screening system using periwinkle cuttings. In ...

OASIS is Automated Statistical Inference for Segmentation, with applications to multiple sclerosis lesion segmentation in MRI.

PubMed

Sweeney, Elizabeth M; Shinohara, Russell T; Shiee, Navid; Mateen, Farrah J; Chudgar, Avni A; Cuzzocreo, Jennifer L; Calabresi, Peter A; Pham, Dzung L; Reich, Daniel S; Crainiceanu, Ciprian M

2013-01-01

Magnetic resonance imaging (MRI) can be used to detect lesions in the brains of multiple sclerosis (MS) patients and is essential for diagnosing the disease and monitoring its progression. In practice, lesion load is often quantified by either manual or semi-automated segmentation of MRI, which is time-consuming, costly, and associated with large inter- and intra-observer variability. We propose OASIS is Automated Statistical Inference for Segmentation (OASIS), an automated statistical method for segmenting MS lesions in MRI studies. We use logistic regression models incorporating multiple MRI modalities to estimate voxel-level probabilities of lesion presence. Intensity-normalized T1-weighted, T2-weighted, fluid-attenuated inversion recovery and proton density volumes from 131 MRI studies (98 MS subjects, 33 healthy subjects) with manual lesion segmentations were used to train and validate our model. Within this set, OASIS detected lesions with a partial area under the receiver operating characteristic curve for clinically relevant false positive rates of 1% and below of 0.59% (95% CI; [0.50%, 0.67%]) at the voxel level. An experienced MS neuroradiologist compared these segmentations to those produced by LesionTOADS, an image segmentation software that provides segmentation of both lesions and normal brain structures. For lesions, OASIS out-performed LesionTOADS in 74% (95% CI: [65%, 82%]) of cases for the 98 MS subjects. To further validate the method, we applied OASIS to 169 MRI studies acquired at a separate center. The neuroradiologist again compared the OASIS segmentations to those from LesionTOADS. For lesions, OASIS ranked higher than LesionTOADS in 77% (95% CI: [71%, 83%]) of cases. For a randomly selected subset of 50 of these studies, one additional radiologist and one neurologist also scored the images. Within this set, the neuroradiologist ranked OASIS higher than LesionTOADS in 76% (95% CI: [64%, 88%]) of cases, the neurologist 66% (95% CI: [52%, 78

Oasis: A high-level/high-performance open source Navier-Stokes solver

NASA Astrophysics Data System (ADS)

Mortensen, Mikael; Valen-Sendstad, Kristian

2015-03-01

Oasis is a high-level/high-performance finite element Navier-Stokes solver written from scratch in Python using building blocks from the FEniCS project (fenicsproject.org). The solver is unstructured and targets large-scale applications in complex geometries on massively parallel clusters. Oasis utilizes MPI and interfaces, through FEniCS, to the linear algebra backend PETSc. Oasis advocates a high-level, programmable user interface through the creation of highly flexible Python modules for new problems. Through the high-level Python interface the user is placed in complete control of every aspect of the solver. A version of the solver, that is using piecewise linear elements for both velocity and pressure, is shown to reproduce very well the classical, spectral, turbulent channel simulations of Moser et al. (1999). The computational speed is strongly dominated by the iterative solvers provided by the linear algebra backend, which is arguably the best performance any similar implicit solver using PETSc may hope for. Higher order accuracy is also demonstrated and new solvers may be easily added within the same framework.

OASIS 2: online application for survival analysis 2 with features for the analysis of maximal lifespan and healthspan in aging research.

PubMed

Han, Seong Kyu; Lee, Dongyeop; Lee, Heetak; Kim, Donghyo; Son, Heehwa G; Yang, Jae-Seong; Lee, Seung-Jae V; Kim, Sanguk

2016-08-30

Online application for survival analysis (OASIS) has served as a popular and convenient platform for the statistical analysis of various survival data, particularly in the field of aging research. With the recent advances in the fields of aging research that deal with complex survival data, we noticed a need for updates to the current version of OASIS. Here, we report OASIS 2 (http://sbi.postech.ac.kr/oasis2), which provides extended statistical tools for survival data and an enhanced user interface. In particular, OASIS 2 enables the statistical comparison of maximal lifespans, which is potentially useful for determining key factors that limit the lifespan of a population. Furthermore, OASIS 2 provides statistical and graphical tools that compare values in different conditions and times. That feature is useful for comparing age-associated changes in physiological activities, which can be used as indicators of "healthspan." We believe that OASIS 2 will serve as a standard platform for survival analysis with advanced and user-friendly statistical tools for experimental biologists in the field of aging research.

Validation of SWEEP for creep, saltation, and suspension in a desert-oasis ecotone

NASA Astrophysics Data System (ADS)

Pi, H.; Sharratt, B.; Feng, G.; Lei, J.; Li, X.; Zheng, Z.

2016-03-01

Wind erosion in the desert-oasis ecotone can accelerate desertification, but little is known about the susceptibility of the ecotone to wind erosion in the Tarim Basin despite being a major source of windblown dust in China. The objective of this study was to test the performance of the Single-event Wind Erosion Evaluation Program (SWEEP) in simulating soil loss as creep, saltation, and suspension in a desert-oasis ecotone. Creep, saltation, and suspension were measured and simulated in a desert-oasis ecotone of the Tarim Basin during discrete periods of high winds in spring 2012 and 2013. The model appeared to adequately simulate total soil loss (ranged from 23 to 2272 g m-2 across sample periods) according to the high index of agreement (d = 0.76). The adequate agreement of the SWEEP in simulating total soil loss was due to the good performance of the model (d = 0.71) in simulating creep plus saltation. The SWEEP model, however, inadequately simulated suspension based upon a low d (⩽0.43). The slope estimates of the regression between simulated and measured suspension and difference of mean suggested that the SWEEP underestimated suspension. The adequate simulation of creep plus saltation thus provides reasonable estimates of total soil loss using SWEEP in a desert-oasis environment.

Pre-shot simulations of far-field ground motion for the Source Physics Experiment (SPE) Explosions at the Climax Stock, Nevada National Security Site: SPE2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mellors, R J; Rodgers, A; Walter, W

2011-10-18

The Source Physics Experiment (SPE) is planning a 1000 kg (TNT equivalent) shot (SPE2) at the Nevada National Security Site (NNSS) in a granite borehole at a depth (canister centroid) of 45 meters. This shot follows an earlier shot of 100 kg in the same borehole at a depth 60 m. Surrounding the shotpoint is an extensive array of seismic sensors arrayed in 5 radial lines extending out 2 km to the north and east and approximately 10-15 to the south and west. Prior to SPE1, simulations using a finite difference code and a 3D numerical model based on themore » geologic setting were conducted, which predicted higher amplitudes to the south and east in the alluvium of Yucca Flat along with significant energy on the transverse components caused by scattering within the 3D volume along with some contribution by topographic scattering. Observations from the SPE1 shot largely confirmed these predictions although the ratio of transverse energy relative to the vertical and radial components was in general larger than predicted. A new set of simulations has been conducted for the upcoming SPE2 shot. These include improvements to the velocity model based on SPE1 observations as well as new capabilities added to the simulation code. The most significant is the addition of a new source model within the finite difference code by using the predicted ground velocities from a hydrodynamic code (GEODYN) as driving condition on the boundaries of a cube embedded within WPP which provides a more sophisticated source modeling capability linked directly to source site materials (e.g. granite) and type and size of source. Two sets of SPE2 simulations are conducted, one with a GEODYN source and 3D complex media (no topography node spacing of 5 m) and one with a standard isotropic pre-defined time function (3D complex media with topography, node spacing of 5 m). Results were provided as time series at specific points corresponding to sensor locations for both translational (x,y,z) and

Large-N Seismic Deployment at the Source Physics Experiment (SPE) Site

NASA Astrophysics Data System (ADS)

Chen, T.; Snelson, C. M.; Mellors, R. J.; Pitarka, A.

2015-12-01

The Source Physics Experiment (SPE) is multi-institutional and multi-disciplinary project that consists of a series of chemical explosion experiments at the Nevada National Security Site. The goal of SPE is to understand the complicated effect of earth structures on source energy partitioning and seismic wave propagation, develop and validate physics-based monitoring, and ultimately better discriminate low-yield nuclear explosions from background seismicity. Deployment of a large number of seismic sensors is planned for SPE to image the full 3-D wavefield with about 500 three-component sensors and 500 vertical component sensors. This large-N seismic deployment will operate near the site of SPE-5 shot for about one month, recording the SPE-5 shot, ambient noise, and additional controlled-sources. This presentation focuses on the design of the large-N seismic deployment. We show how we optimized the sensor layout based on the geological structure and experiment goals with a limited number of sensors. In addition, we will also show some preliminary record sections from deployment. This work was conducted under Contract No. DE-AC52-06NA25946 with the U.S. Department of Energy.

Development of a reliable and highly sensitive, digital PCR-based assay for early detection of HLB

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB) is caused by a phloem-limited bacterium, Ca. Liberibacter asiaticus (Las) in the United States. The bacterium often is present at a low concentration and unevenly distributed in the early stage of infection, making reliable and early diagnosis a serious challenge. Conventional d...

Oasis in Iraq: Universities Flourish in Kurdistan

ERIC Educational Resources Information Center

Krieger, Zvika

2007-01-01

The campus of Salahadin University--peaceful, bustling, and collegial-- is a rare sight in Iraq, where sectarian violence has brought the higher education system to the verge of collapse. Home to the country's historically repressed four million to five million ethnic Kurds, it is an oasis of stability and tranquility while much of the rest of…

Analysis of land cover change and its driving forces in a desert oasis landscape of southern Xinjiang, China

NASA Astrophysics Data System (ADS)

Amuti, T.; Luo, G.

2014-07-01

The combined effects of drought, warming and the changes in land cover have caused severe land degradation for several decades in the extremely arid desert oases of Southern Xinjiang, Northwest China. This study examined land cover changes during 1990-2008 to characterize and quantify the transformations in the typical oasis of Hotan. Land cover classifications of these images were performed based on the supervised classification scheme integrated with conventional vegetation and soil indexes. Change-detection techniques in remote sensing (RS) and a geographic information system (GIS) were applied to quantify temporal and spatial dynamics of land cover changes. The overall accuracies, Kappa coefficients, and average annual increase rate or decrease rate of land cover classes were calculated to assess classification results and changing rate of land cover. The analysis revealed that major trends of the land cover changes were the notable growth of the oasis and the reduction of the desert-oasis ecotone, which led to accelerated soil salinization and plant deterioration within the oasis. These changes were mainly attributed to the intensified human activities. The results indicated that the newly created agricultural land along the margins of the Hotan oasis could result in more potential areas of land degradation. If no effective measures are taken against the deterioration of the oasis environment, soil erosion caused by land cover change may proceed. The trend of desert moving further inward and the shrinking of the ecotone may lead to potential risks to the eco-environment of the Hotan oasis over the next decades.

Groundwater mixing and mineralization processes in a mountain-oasis-desert basin, northwest China: hydrogeochemistry and environmental tracer indicators

NASA Astrophysics Data System (ADS)

Ma, Bin; Jin, Menggui; Liang, Xing; Li, Jing

2018-02-01

Hydrogeochemistry and environmental tracers (2H, 18O, 87Sr/86Sr) in precipitation, river and reservoir water, and groundwater have been used to determine groundwater recharge sources, and to identify mixing characteristics and mineralization processes in the Manas River Basin (MRB), which is a typical mountain-oasis-desert ecosystem in arid northwest China. The oasis component is artificial (irrigation). Groundwater with enriched stable isotope content originates from local precipitation and surface-water leakage in the piedmont alluvial-oasis plain. Groundwater with more depleted isotopes in the north oasis plain and desert is recharged by lateral flow from the adjacent mountains, for which recharge is associated with high altitude and/or paleo-water infiltrating during a period of much colder climate. Little evaporation and isotope exchange between groundwater and rock and soil minerals occurred in the mountain, piedmont and oasis plain. Groundwater δ2H and δ18O values show more homogeneous values along the groundwater flow direction and with well depths, indicating inter-aquifer mixing processes. A regional contrast of groundwater allows the 87Sr/86Sr ratios and δ18O values to be useful in a combination with Cl, Na, Mg, Ca and Sr concentrations to distinguish the groundwater mixing characteristics. Two main processes are identified: groundwater lateral-flow mixing and river leakage in the piedmont alluvial-oasis plain, and vertical mixing in the north oasis plain and the desert. The 87Sr/86Sr ratios and selected ion ratios reveal that carbonate dissolution and mixing with silicate from the southern mountain area are primarily controlling the strontium isotope hydrogeochemistry.

Overexpression of a modified plant thionin enhances disease resistance to citrus canker and huanglongbing (HLB, citrus greening)

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB or citrus greening disease) caused by Candidatus Liberibacter asiaticus (Las) is a great threat to the United States citrus industry. Citrus canker is also an economically important disease associated with a bacterial pathogen (Xanthomonas citri). In this study, we characterized e...

18 CFR 37.8 - Obligations of OASIS users.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME INFORMATION SYSTEMS § 37.8... initiating a significant amount of automated queries. The OASIS user must also notify the Responsible Party one month in advance of expected significant increases in the volume of automated queries. [Order 605...

CAVIAR: CLASSIFICATION VIA AGGREGATED REGRESSION AND ITS APPLICATION IN CLASSIFYING OASIS BRAIN DATABASE

PubMed Central

Chen, Ting; Rangarajan, Anand; Vemuri, Baba C.

2010-01-01

This paper presents a novel classification via aggregated regression algorithm – dubbed CAVIAR – and its application to the OASIS MRI brain image database. The CAVIAR algorithm simultaneously combines a set of weak learners based on the assumption that the weight combination for the final strong hypothesis in CAVIAR depends on both the weak learners and the training data. A regularization scheme using the nearest neighbor method is imposed in the testing stage to avoid overfitting. A closed form solution to the cost function is derived for this algorithm. We use a novel feature – the histogram of the deformation field between the MRI brain scan and the atlas which captures the structural changes in the scan with respect to the atlas brain – and this allows us to automatically discriminate between various classes within OASIS [1] using CAVIAR. We empirically show that CAVIAR significantly increases the performance of the weak classifiers by showcasing the performance of our technique on OASIS. PMID:21151847

CAVIAR: CLASSIFICATION VIA AGGREGATED REGRESSION AND ITS APPLICATION IN CLASSIFYING OASIS BRAIN DATABASE.

PubMed

Chen, Ting; Rangarajan, Anand; Vemuri, Baba C

2010-04-14

This paper presents a novel classification via aggregated regression algorithm - dubbed CAVIAR - and its application to the OASIS MRI brain image database. The CAVIAR algorithm simultaneously combines a set of weak learners based on the assumption that the weight combination for the final strong hypothesis in CAVIAR depends on both the weak learners and the training data. A regularization scheme using the nearest neighbor method is imposed in the testing stage to avoid overfitting. A closed form solution to the cost function is derived for this algorithm. We use a novel feature - the histogram of the deformation field between the MRI brain scan and the atlas which captures the structural changes in the scan with respect to the atlas brain - and this allows us to automatically discriminate between various classes within OASIS [1] using CAVIAR. We empirically show that CAVIAR significantly increases the performance of the weak classifiers by showcasing the performance of our technique on OASIS.

Study of acrylamide in coffee using an improved liquid chromatography mass spectrometry method: Investigation of colour changes and acrylamide formation in coffee during roasting.

PubMed

Senyuva, Hamide Z; Gökmen, Vural

2005-03-01

An improved analytical method for the determination of acrylamide in coffee is described using liquid chromatography coupled to mass spectrometric detection (LC-MS). A variety of instant, ground and laboratory roasted coffee samples were analysed using this method. The sample preparation entails extraction of acrylamide with methanol, purification with Carrez I and II solutions, evaporation and solvent change to water, and clean-up with an Oasis HLB solid-phase extraction (SPE) cartridge. The chromatographic conditions allowed separation of acrylamide and the remaining matrix co-extractives with accurate and precise quantification of acrylamide during MS detection in SIM mode. Recoveries for the spiking levels of 50, 100, 250 and 500?microg/kg ranged between 99 and 100% with relative standard deviations of less than 2%. The effects of roasting on the formation of acrylamide and colour development were also investigated at 150, 200 and 225 degrees C. Change in the CIE (Commission Internationale de l'Eclairage) a* colour value was found to show a good correlation with the change in acrylamide. CIE a* and acrylamide data was fitted to a non-linear logarithmic function for the estimation of acrylamide level in coffee. Measured acrylamide levels in commercial roasted coffees compared well with the predicted acrylamide levels from the CIE a* values.

Trace determination of 10 beta-lactam antibiotics in environmental and food samples by capillary liquid chromatography.

PubMed

Bailón-Pérez, M I; García-Campaña, A M; del Olmo-Iruela, M; Gámiz-Gracia, L; Cruces-Blanco, C

2009-11-20

A sensitive and reliable method using capillary HPLC with UV-diode array detection (DAD) has been developed and validated for the trace determination of residues of 10 beta-lactam antibiotics of human and veterinary use, in milk, chicken meat and environmental water samples. The analytes included ampicillin, amoxicillin, penicillin V, penicillin G, cloxacillin, oxacillin, dicloxacillin, nafcillin, piperacillin and clavulanic acid. Legal levels are regulated by the EU Council regulation 2377/90 in animal edible tissues for these compounds. For food analysis, a solid-phase extraction (SPE) procedure consisting in a tandem of Oasis HLB and Alumina N cartridges was applied for off-line preconcentration and cleanup. For water analysis, the first step was only necessary. The limits of detection for the studied compounds were between 0.04-0.06 microg l(-1) for water samples and 0.80-1.40 microg l(-1) (or microg kg(-1)) in the case of foods derived from animals. Average recoveries for fortified samples at different concentration levels ranged between 82.9% and 98.2%, with relative standard deviations (RSDs) lower than 9%. The method showed the advantages of capillary HPLC for the detection of these widely applied antibiotics in different samples at very low concentration levels.

Policies, Land Use, and Water Resource Management in an Arid Oasis Ecosystem

NASA Astrophysics Data System (ADS)

Xue, Xian; Liao, Jie; Hsing, Youtian; Huang, Cuihua; Liu, Famin

2015-05-01

This paper addresses two questions concerning the relationship between state policies and environmental transformation in China in the past four decades. The first one deals with the promotion of agricultural productivity since the 1980s; the second, the water conservation measures as a response to the water crisis that peaked in the early 2000s. We had chosen Minqin County in northwestern China, one of the most fragile arid oasis systems in the world, as the study area. We found that the irrigated farmland in up and midstream areas had greatly expanded between the 1980s and the 2000s under the government policy of promoting commodity grain production. As a result, the runoff flowing into Minqin Oasis had reduced 80 % from the 1950s to early 2000s. Irrigated farmland in Minqin Oasis expanded 15.76 % from 1995 to 2000. In the 2000s, because of the changing policy discourse that has shifted from productivity to conservation, a new set of environmentally framed policies has restructured agricultural production in Minqin by 2005. These new policies included establishing a watershed-level water management system, promoting drought resistant crops, introducing water-saving irrigation measures, and forced reduction of irrigated farming acreage. These policies have produced positive results in terms of greater coverage of vegetation, rising ground water table, and reduction of evaporation. Nevertheless, new policies have also brought new challenges to both farmers and policy makers to keep the balance between poverty reduction and environmental sustainability in Minqin Oasis in the historically poor region in China's Northwest.

Effective antibiotics against 'Candidatus Liberibacter asiaticus' in HLB-affected citrus plants identified via the graft-based evaluation.

PubMed

Zhang, Muqing; Guo, Ying; Powell, Charles A; Doud, Melissa S; Yang, Chuanyu; Duan, Yongping

2014-01-01

Citrus huanglongbing (HLB), caused by three species of fastidious, phloem-limited 'Candidatus Liberibacter', is one of the most destructive diseases of citrus worldwide. To date, there is no established cure for this century-old and yet, newly emerging disease. As a potential control strategy for citrus HLB, 31 antibiotics were screened for effectiveness and phytotoxicity using the optimized graft-based screening system with 'Candidatus Liberibacter asiaticus' (Las)-infected citrus scions. Actidione and Oxytetracycline were the most phytotoxic to citrus with less than 10% of scions surviving and growing; therefore, this data was not used in additional analyses. Results of principal component (PCA) and hierarchical clustering analyses (HCA) demonstrated that 29 antibiotics were clustered into 3 groups: highly effective, partly effective, and not effective. In spite of different modes of actions, a number of antibiotics such as, Ampicillin, Carbenicillin, Penicillin, Cefalexin, Rifampicin and Sulfadimethoxine were all highly effective in eliminating or suppressing Candidatus Liberibacter asiaticus indicated by both the lowest Las infection rate and titers of the treated scions and inoculated rootstock. The non-effective group, including 11 antibiotics alone with three controls, such as Amikacin, Cinoxacin, Gentamicin, Kasugamycin, Lincomycin, Neomycin, Polymixin B and Tobramycin, did not eliminate or suppress Las in the tested concentrations, resulting in plants with increased titers of Las. The other 12 antibiotics partly eliminated or suppressed Las in the treated and graft-inoculated plants. The effective and non-phytotoxic antibiotics could be potential candidates for control of citrus HLB, either for the rescue of infected citrus germplasm or for restricted field application.

Differences in SpeB protease activity among group A streptococci associated with superficial, invasive, and autoimmune disease

PubMed Central

Walwyn, Odaelys L.; Tanz, Robert R.; Shulman, Stanford T.; Kabat, William

2017-01-01

The secreted cysteine proteinase SpeB is an important virulence factor of group A streptococci (GAS), whereby SpeB activity varies widely among strains. To establish the degree to which SpeB activity correlates with disease, GAS organisms were recovered from patients with pharyngitis, impetigo, invasive disease or acute rheumatic fever (ARF), and selected for analysis using rigorous sampling criteria; >300 GAS isolates were tested for SpeB activity by casein digestion assays, and each GAS isolate was scored as a SpeB-producer or non-producer. Highly significant statistical differences (p < 0.01) in SpeB production are observed between GAS recovered from patients with ARF (41.5% SpeB-non-producers) compared to pharyngitis (20.5%), invasive disease (16.7%), and impetigo (5.5%). SpeB activity differences between pharyngitis and impetigo isolates are also significant, whereas pharyngitis versus invasive isolates show no significant difference. The disproportionately greater number of SpeB-non-producers among ARF-associated isolates may indicate an altered transcriptional program for many rheumatogenic strains and/or a protective role for SpeB in GAS-triggered autoimmunity. PMID:28545045

Interobserver reliability of a "Standardized Psychiatric Examination" (SPE) for case ascertainment (DSM-III).

PubMed

Romanoski, A J; Nestadt, G; Chahal, R; Merchant, A; Folstein, M F; Gruenberg, E M; McHugh, P R

1988-02-01

The authors describe the Standardized Psychiatric Examination (SPE), a new method for conducting psychiatric examinations in both clinical and research settings that preserves the clinical method. The SPE provides a consistent replicable format for eliciting and recording psychiatric history, signs, and symptoms without perturbing the patient-clinician interaction. By means of the SPE, the clinician can formulate diagnoses using DSM-III or ICD-9 criteria and yet generate CATEGO profiles derived from the Present State Examination, 9th edition. Psychiatrists using the SPE demonstrated high interrater reliability in ascertaining individual psychopathological symptoms (Kappa range, 0.55 to 1.0) and in making DSM-III diagnoses (Kappa range, 0.79 to 1.0) among a sample of study subjects (N = 43) drawn from both a psychiatric inpatient population and a large community sample of nonpatients from the Epidemiological Catchment Area (ECA) study. The implications of the SPE for clinical practice and for research are discussed.

Membrane water-flow rate in electrolyzer cells with a solid polymer electrolyte (SPE)

NASA Astrophysics Data System (ADS)

Li, Xiaojin; Qu, Shuguo; Yu, Hongmei; Hou, Ming; Shao, Zhigang; Yi, Baolian

Water-flow rate across Nafion membrane in SPE electrolyzer cells was measured and modelled. From the analysis of water transport mechanisms in SPE water electrolysis, the water-flow rate through membrane can be described by the electro-osmotic drag. The calculated electro-osmotic drag coefficients, n d, for the membrane in SPE electrolysis cells at different temperatures were compared with literature and in good agreement with those of Ge et al. and Ise et al. To describe the water-flow rate through membrane more accurately, a linear fit of n d as a function of temperature for the membrane in SPE water electrolysis was proposed in this paper. This paper studied the membrane water-flow rate experimentally and mathematically, which is of importance in the designing and optimization of the process of SPE water electrolysis. This paper also provided a novel method for measuring the electro-osmotic drag coefficient of Nafion membrane in contact with liquid water, acid and methanol solutions, etc.

18 CFR 37.8 - Obligations of OASIS users.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Obligations of OASIS users. 37.8 Section 37.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME INFORMATION SYSTEMS § 37.8...

Vps33b pathogenic mutations preferentially affect VIPAS39/SPE-39-positive endosomes.

PubMed

Tornieri, Karine; Zlatic, Stephanie A; Mullin, Ariana P; Werner, Erica; Harrison, Robert; L'hernault, Steven W; Faundez, Victor

2013-12-20

Mutations in Vps33 isoforms cause pigment dilution in mice (Vps33a, buff) and Drosophila (car) and the neurogenic arthrogryposis, renal dysfunction and cholestasis syndrome in humans (ARC1, VPS33B). The later disease is also caused by mutations in VIPAS39, (Vps33b interacting protein, apical-basolateral polarity regulator, SPE-39 homolog; ARC2), a protein that interacts with the HOmotypic fusion and Protein Sorting (HOPS) complex, a tether necessary for endosome-lysosome traffic. These syndromes offer insight into fundamental endosome traffic processes unique to metazoans. However, the molecular and cellular mechanisms underlying these mutant phenotypes remain poorly understood. Here we investigate interactions of wild-type and disease-causing mutations in VIPAS39/SPE-39 and Vps33b by yeast two hybrid, immunoprecipitation and quantitative fluorescent microscopy. We find that although few mutations prevent interaction between VIPAS39/SPE-39 and Vps33b, some mutants fragment VIPAS39/SPE-39-positive endosomes, but all mutants alter the subcellular localization of Vps33b to VIPAS39/SPE-39-positive endosomes. Our data suggest that the ARC syndrome may result through impaired VIPAS39/SPE-39 and Vps33b-dependent endosomal maturation or fusion.

Environmental engineering interventions to control the expansion of salty lakes and marshes in siwa oasis.

PubMed

El-Naggar, Hesham M

2010-01-01

The main activity in Siwa Oasis society is the agriculture, it depends on the groundwater. The agricultural drainage water and the unused saline water of naturally flowing springs are poured into four main salty lakes. This leads to an increase in the surface area of the saltwater lakes, marshes and rise in water table levels. to investigate some environmental engineering interventions to control the expansion of saltwater surface area in Siwa Oasis. Field visits, observation sheets and questionnaire survey with farmers were carried out to find out the main environmental problems in the Oasis. Environmental survey was carried out to collect different rocks and stones samples as natural construction materials from the desert that surrounds Siwa Oasis. Physical analyses, chemical composition and principal mechanical parameters were conducted on the collected samples. After the analysis, the safa rocks were the best natural construction materials in the Siwa Oasis. So, it could be used to build a construction wall around the salty lakes and marshes. Walls could convert the lakes into basins. The water will be evaporated at high rate during summer season by solar energy. After evaporation, the remaining salty rock named "karshef" can be easily collected from the lakes to be used as a low cost construction material for traditional building houses in Siwa Oasis. Therefore, the water level of lakes will be reduced to dryness and land could be reused as agricultural land. Among different rocks, safa rocks proved to be the best natural construction materials to construct a defense wall around the lakes and marshes. They will save about 80% of the concrete cost. The formed karshef rocks from the lakes will be used in the construction of the traditional building houses which will save about 90% of the concrete buildings. This intervention will save energy as it exchanges fuel consuming man-made material such as cement with naturally made material. This can reduce the green

HPLC-DAD method development and validation for the quantification of hydroxymethylfurfural in corn chips by means of response surface optimisation.

PubMed

Salvatierra Virgen, Sara; Ceballos-Magaña, Silvia Guillermina; Salvatierra-Stamp, Vilma Del Carmen; Sumaya-Martínez, Maria Teresa; Martínez-Martínez, Francisco Javier; Muñiz-Valencia, Roberto

2017-12-01

In recent years, there has been an increased concern about the presence of toxic compounds derived from the Maillard reaction produced during food cooking at high temperatures. The main toxic compounds derived from this reaction are acrylamide and hydroxymethylfurfural (HMF). The majority of analytical methods require sample treatments using solvents which are highly polluting for the environment. The difficulty of quantifying HMF in complex fried food matrices encourages the development of new analytical methods. This paper provides a rapid, sensitive and environmentally-friendly analytical method for the quantification of HMF in corn chips using HPLC-DAD. Chromatographic separation resulted in a baseline separation for HMF in 3.7 min. Sample treatment for corn chip samples first involved a leaching process using water and afterwards a solid-phase extraction (SPE) using HLB-Oasis polymeric cartridges. Sample treatment optimisation was carried out by means of Box-Behnken fractional factorial design and Response Surface Methodolog y to examine the effects of four variables (sample weight, pH, sonication time and elution volume) on HMF extraction from corn chips. The SPE-HPLC-DAD method was validated. The limits of detection and quantification were 0.82 and 2.20 mg kg -1 , respectively. Method precision was evaluated in terms of repeatability and reproducibility as relative standard deviations (RSDs) using three concentration levels. For repeatability, RSD values were 6.9, 3.6 and 2.0%; and for reproducibility 18.8, 7.9 and 2.9%. For a ruggedness study the Yuden test was applied and the result demonstrated the method as robust. The method was successfully applied to different corn chip samples.

Fondaparinux and acute coronary syndromes: update on the OASIS 5-6 studies.

PubMed

Schiele, François

2010-04-15

Anticoagulant therapy is a major component in the management of acute coronary syndromes (ACS). Four anticoagulant agents are currently commercially available for ACS, namely unfractionated heparin (UFH), enoxaparin, bivalirudin and fondaparinux. We describe the advantages of fondaparinux and the reasons that have hampered its uptake into routine management of ACS. Fondaparinux was shown to be efficacious in the prevention of deep vein thrombosis vs low-molecular-weight heparins, while in the setting of venous thrombo-embolic disease, it was shown to be noninferior to enoxaparin and UFH. Two pivotal studies have demonstrated the efficacy of fondaparinux as an anticoagulant in the setting of ACS, namely OASIS-5 in non-ST elevation ACS, and OASIS-6 in ST elevation myocardial infarction (MI). In OASIS-5, fondaparinux was shown to be noninferior to enoxaparin in terms of death, MI or refractory ischemia at 9 days. Furthermore, a 50% reduction in bleeding complications was obtained with fondaparinux vs enoxaparin, leading to a risk reduction for death. In OASIS-6, fondaparinux was shown to be superior to the comparator (UFH or placebo). European and North American guidelines give fondaparinux a Grade 1A and 1B recommendation respectively, but uptake of fondaparinux in routine practice has been slow. We explore reasons for this, such as prevailing doubts about the efficacy of fondaparinux in the setting of angioplasty, the problem of catheter thrombosis, and the lack of antidote in case of bleeding complications. With the exception of primary angioplasty, fondaparinux is as effective as enoxaparin or UFH, but is also associated with a considerable reduction in bleeding complications, and thus, an undeniable net clinical benefit.

Condition and Health of Rufous Bush Robin (Cercotrichas galactotes) Nestlings in a Polluted Oasis Habitat in Southern Tunisia.

PubMed

Alaya-Ltifi, Leila; Hayder-Benyahya, Nawel; Selmi, Slaheddine

2015-06-01

We investigated whether the proximity to the Gabès-Ghannouche factory complex of phosphate treatment, in south-eastern Tunisia, was associated with notable changes in the condition and health of Rufous bush robin (Cercotrichas galactotes) nestlings hatched in the neighbouring oasis habitat. Results demonstrated that excrements of nestlings hatched in one oasis close to the factory complex contained higher concentrations of lead and zinc than the excrements of nestlings from one oasis situated 20 km away. Furthermore, when effects of age and nestling number in the nest were controlled, nestlings hatched near the factory complex showed reduced tarsus length, rectrix length, haematocrit level and haemoglobin concentration, but higher levels of fluctuating asymmetry compared to those from the more distant oasis. Overall, results suggest that the proximity to the factory complex was associated with increased exposure to metals and deterioration in nestling condition and development.

Velocity Model Using the Large-N Seismic Array from the Source Physics Experiment (SPE)

NASA Astrophysics Data System (ADS)

Chen, T.; Snelson, C. M.

2016-12-01

The Source Physics Experiment (SPE) is a multi-institutional, multi-disciplinary project that consists of a series of chemical explosions conducted at the Nevada National Security Site (NNSS). The goal of SPE is to understand the complicated effect of geological structures on seismic wave propagation and source energy partitioning, develop and validate physics-based modeling, and ultimately better monitor low-yield nuclear explosions. A Large-N seismic array was deployed at the SPE site to image the full 3D wavefield from the most recent SPE-5 explosion on April 26, 2016. The Large-N seismic array consists of 996 geophones (half three-component and half vertical-component sensors), and operated for one month, recording the SPE-5 shot, ambient noise, and additional controlled-sources (a large hammer). This study uses Large-N array recordings of the SPE-5 chemical explosion to develop high resolution images of local geologic structures. We analyze different phases of recorded seismic data and construct a velocity model based on arrival times. The results of this study will be incorporated into the large modeling and simulation efforts as ground-truth further validating the models.

Sonographic assessment of the anal sphincter after obstetric anal sphincter injury (OASI) using transperineal ultrasound (TPUS).

PubMed

Eisenberg, Vered H; Valsky, Dan V; Yagel, Simcha

2018-03-24

Obstetric anal sphincter injury (OASI) is the most common cause of anal incontinence and ano-rectal symptoms in women 1 . Reported rates of anal incontinence following primary repair of OASI range between 15-61%, with a mean of 39% 2, 3 . Other possible complications of OASI include perineal pain, dyspareunia, and less commonly, abscess formation, wound breakdown, and rectovaginal fistulae. Symptom onset may occur immediately, several years postpartum, or only late in life when aging of tissues adds to the delivery insult. Having sustained an OASI may impact significantly on women's physical and emotional health. Missed OASI, inadequate repair or lack of follow up are potential sources of litigation 4 . The reported incidence of OASI may be as high as 4-6.6% 4 , averaging 2.9% in the UK 3 . The incidence is higher in primiparae (6.1%) than in multiparae (1.7%) 3 . Recent years are seeing an increased awareness and structured training programs, which appear to have resulted in an increase in the detection rate of OASI 3 . The following risk factors have been identified with varying risk rates reported 3 : Asian ethnicity (OR 2.27, 95% CI 2.14-2.41), nulliparity (relative risk [RR] 6.97, 95% CI 5.40-8.99), birth weight greater than 4 kg (OR 2.27, 95% CI 2.18-2.36), shoulder dystocia (OR 1.90, 95% CI 1.72-2.08), occipito-posterior position (RR 2.44, 95% CI 2.07-2.89), prolonged second stage of labor (up to RR 2.02, 95% CI 1.62-2.51 after four hours duration). Instrumental deliveries and episiotomy use have been extensively studied resulting in the following evidence: Vacuum delivery without episiotomy (OR 1.89, 95% CI 1.74-2.05); vacuum delivery with episiotomy is protective (OR 0.57, 95% CI 0.51-0.63); forceps delivery without episiotomy carries the highest potential risk (OR 6.53, 95% CI 5.57-7.64); and forceps delivery with episiotomy (OR 1.34, 95% CI 1.21-1.49). Other potential risk factors have been suggested with varying evidence such as advanced maternal age at

Effective Antibiotics against ‘Candidatus Liberibacter asiaticus’ in HLB-Affected Citrus Plants Identified via the Graft-Based Evaluation

PubMed Central

Powell, Charles A.; Doud, Melissa S.; Yang, Chuanyu; Duan, Yongping

2014-01-01

Citrus huanglongbing (HLB), caused by three species of fastidious, phloem-limited ‘Candidatus Liberibacter’, is one of the most destructive diseases of citrus worldwide. To date, there is no established cure for this century-old and yet, newly emerging disease. As a potential control strategy for citrus HLB, 31 antibiotics were screened for effectiveness and phytotoxicity using the optimized graft-based screening system with ‘Candidatus Liberibacter asiaticus’ (Las)-infected citrus scions. Actidione and Oxytetracycline were the most phytotoxic to citrus with less than 10% of scions surviving and growing; therefore, this data was not used in additional analyses. Results of principal component (PCA) and hierarchical clustering analyses (HCA) demonstrated that 29 antibiotics were clustered into 3 groups: highly effective, partly effective, and not effective. In spite of different modes of actions, a number of antibiotics such as, Ampicillin, Carbenicillin, Penicillin, Cefalexin, Rifampicin and Sulfadimethoxine were all highly effective in eliminating or suppressing Candidatus Liberibacter asiaticus indicated by both the lowest Las infection rate and titers of the treated scions and inoculated rootstock. The non-effective group, including 11 antibiotics alone with three controls, such as Amikacin, Cinoxacin, Gentamicin, Kasugamycin, Lincomycin, Neomycin, Polymixin B and Tobramycin, did not eliminate or suppress Las in the tested concentrations, resulting in plants with increased titers of Las. The other 12 antibiotics partly eliminated or suppressed Las in the treated and graft-inoculated plants. The effective and non-phytotoxic antibiotics could be potential candidates for control of citrus HLB, either for the rescue of infected citrus germplasm or for restricted field application. PMID:25372135

Fighting HLB with Citrus tristeza virus (CTV): Heterogeneity in the genome ends of CTV is an important consideration

USDA-ARS?s Scientific Manuscript database

As California prepares for a potential showdown with Huanglongbing (HLB), contemporary disease control strategies that use low inputs, yet produce high value control, are needed to manage the disease. With biotechnology, Citrus tristeza virus (CTV) may be developed into a tool for protection or trea...

Soil Susceptibility to Macropore Flow Across a Desert-Oasis Ecotone of the Hexi Corridor, Northwest China

NASA Astrophysics Data System (ADS)

Zhang, Yongyong; Zhao, Wenzhi; He, Jianhua; Fu, Li

2018-02-01

Macropore flow not only provides a fast pathway for water and solute transport and increases the risks of water and nutrient loss but also enhances soil aeration and groundwater recharge. However, macropore flow characteristics in irrigated oasis soils subject to continuous crop cultivation are poorly understood. This study was to investigate the effect of continuous cultivation on soil properties and macropore flow and to quantify the changes in macropore flow characteristics in an old oasis field (>50 years of cultivation, OOF), young oasis field (20 years, YOF), and adjacent uncultivated sandy area (0 year, USL) in Northwest China. Triplicate soil samples were collected from each site to investigate soil properties. Dye tracer experiments with also three replicates were conducted at each site. The degree of macropore flow (i.e., parameters of macropore flow) was highest at the OOF, intermediate at the YOF, and minimal at the USL. The macropore flow fraction (i.e., fraction of total infiltration flows through macropore flow pathways) at the OOF was 3.4 times greater than at the USL. The heterogeneous infiltration pattern at the OOF was dominated by macropore flow, while funnel flow was predominant at the USL. Long-term irrigation with silt-laden river water has increased silt + clay contents of the oasis soils. Irrigation and high-input crop cultivation also increased organic matter. These changes in soil properties contributed to the interaggregate voids formation. The conversion of native desert soils to irrigated croplands increases the degree of macropore flow, which might enhance groundwater recharge in the desert-oasis ecotone.

Theoretical performance of hydrogen-bromine rechargeable SPE fuel cell

NASA Technical Reports Server (NTRS)

Savinell, Robert F.; Fritts, S. D.

1987-01-01

A mathematical model was formulated to describe the performance of a hydrogen-bromine fuel cell. Porous electrode theory was applied to the carbon felt flow-by electrode and was coupled to theory describing the solid polymer electrolyte (SPE) system. Parametric studies using the numerical solution to this model were performed to determine the effect of kinetic, mass transfer, and design parameters on the performance of the fuel cell. The results indicate that the cell performance is most sensitive to the transport properties of the SPE membrane. The model was also shown to be a useful tool for scale-up studies.

Spacecraft Solar Particle Event (SPE) Shielding: Shielding Effectiveness as a Function of SPE model as Determined with the FLUKA Radiation Transport Code

NASA Technical Reports Server (NTRS)

Koontz, Steve; Atwell, William; Reddell, Brandon; Rojdev, Kristina

2010-01-01

Analysis of both satellite and surface neutron monitor data demonstrate that the widely utilized Exponential model of solar particle event (SPE) proton kinetic energy spectra can seriously underestimate SPE proton flux, especially at the highest kinetic energies. The more recently developed Band model produces better agreement with neutron monitor data ground level events (GLEs) and is believed to be considerably more accurate at high kinetic energies. Here, we report the results of modeling and simulation studies in which the radiation transport code FLUKA (FLUktuierende KAskade) is used to determine the changes in total ionizing dose (TID) and single-event environments (SEE) behind aluminum, polyethylene, carbon, and titanium shielding masses when the assumed form (i. e., Band or Exponential) of the solar particle event (SPE) kinetic energy spectra is changed. FLUKA simulations have fully three dimensions with an isotropic particle flux incident on a concentric spherical shell shielding mass and detector structure. The effects are reported for both energetic primary protons penetrating the shield mass and secondary particle showers caused by energetic primary protons colliding with shielding mass nuclei. Our results, in agreement with previous studies, show that use of the Exponential form of the event

Differences in secondary metabolites in leaves from orange trees (Citrus sinensis L.) affected with greening disease (Huanglongbing) (HLB)

USDA-ARS?s Scientific Manuscript database

Preliminary analyses by HPLC-MS of methanolic extracts of two sets of orange leaves that are symptomatic of the Greening Disease (HLB) have shown several consistent differences. The main flavonoids in symptomatic and nonsymptomatic leaves were monitored in the HPLC chromatograms at 330 nm, and signi...

Scarlet fever is caused by a limited number of Streptococcus pyogenes lineages and is associated with the exotoxin genes ssa, speA and speC.

PubMed

Silva-Costa, Catarina; Carriço, Joao A; Ramirez, Mario; Melo-Cristino, Jose

2014-03-01

Several outbreaks of scarlet fever caused by Streptococcus pyogenes were recently reported. Scarlet fever is historically considered a toxin-mediated disease, dependent on the production of the exotoxins SpeA and SpeC, but a strict association between scarlet fever and these exotoxins is not always detected. The aims of this study were to characterize the scarlet fever bacterial isolates recovered from patients in a Lisbon hospital and to identify any distinctive characteristics of such isolates. We characterized a collection of 303 pharyngeal S. pyogenes collected between 2002 and 2008. One-hundred and one were isolated from scarlet fever patients and 202 were associated to a diagnosis of tonsillo-pharyngitis. Isolates were characterized by T and emm typing, pulsed field gel electrophoresis profiling and superantigen gene profiling. The diversity of the scarlet fever isolates was lower than that of the pharyngitis isolates. Specific lineages of emm87, emm4 and emm3 were overrepresented in scarlet fever isolates but only 1 pulsed field gel electrophoresis major lineage was significantly associated with scarlet fever. Multivariate analysis indicated associations of ssa, speA and speC with scarlet fever. In nonoutbreak conditions, scarlet fever is caused by a number of distinct genetic lineages. The lower diversity of these isolates and the association with specific exotoxin genes indicates that some lineages are more prone to cause this presentation than others even in nonoutbreak conditions.

Comparison of several solid-phase extraction sorbents for continuous determination of amines in water by gas chromatography-mass spectrometry.

PubMed

Jurado-Sánchez, Beatriz; Ballesteros, Evaristo; Gallego, Mercedes

2009-08-15

A semiautomatic method has been proposed for the determination of different types of amines in water samples including anilines, chloroanilines, N-nitrosamines and aliphatic amines. The analytes were retained on a solid-phase extraction sorbent column and after elution, 1 microL of the extract was analysed by gas chromatography coupled with electron impact ionization mass spectrometry. A systematic overview is given of the advantages and disadvantages of several sorbents (LiChrolut EN, Oasis HLB, RP-C(18), graphitized carbon black, fullerenes and nanotubes) in the retention of amine compounds and based on sensitivity, selectivity and reliability. The retention efficiency for the studied amines was higher (ca. 100%) with LiChrolut EN and Oasis HLB than it was with RP-C(18) and fullerenes (53 and 62%, respectively, on average). Detection limits of 0.5-16 ng L(-1) for the 27 amines studied were obtained when using a sorbent column containing 75 mg of LiChrolut EN for 100mL of sample, the RSD being lower than 6.5%. The method was applied with good accuracy and precision in the determination of amines in various types of water including river, pond, tap, well, drinking, swimming pool and waste.

Using Spectral Losses to Map a Damage Zone for the Source Physics Experiments (SPE)

NASA Astrophysics Data System (ADS)

Knox, H. A.; Abbott, R. E.; Bonal, N.; Preston, L. A.

2013-12-01

We performed a series of cross-borehole seismic experiments in support of the Source Physics Experiments (SPE). These surveys, which were conducted in a granitic body using a sparker source and hydrophone string, were designed to image the damage zone from two underground explosions (SPE2 and SPE3). We present results here from a total of six boreholes (the explosive shot emplacement hole and 5 satellite holes, 20-35 meters away) where we found a marked loss of high frequency energy in ray paths traversing the region near the SPE explosions. Specifically, the frequencies above ~400 Hz were lost in a region centered around 45 meters depth, coincident with SPE2 and SPE3 shots. We further quantified these spectral losses, developed a map of where they occur, and evaluated the attenuation effects of raypath length (i.e. source-receiver offset). We attribute this severe attenuation to the inelastic damage (i.e. cracking and pulverizing) caused by the large chemical explosions and propose that frequency attenuation of this magnitude provides yet another tool for detecting the damage due to large underground explosions. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

A cephalometric study of skulls from the Bahriyah oasis

PubMed Central

Zaki, Moushira Erfan; Soliman, Muhammad Al-Tohamy; El-Bassyouni, Hala T.

2012-01-01

Objectives: To determine the craniofacial characteristics of crania from the Bahariyah oasis dating from the Greco-Roman period and to compare their cephalometric traits with other ancient Egyptian samples from various time periods and to evaluate sexual dimorphism. Materials and Methods: The sample comprised 149 skulls (90 males and 59 females), belonging to the Greco-Roman (332 B.C. – 395 A.D.). Lateral and postero-anterior cephalograms were taken. Sixteen linear measurements were analyzed and six indices were calculated. Results: Significant differences were found between males and females almost in all measurements. All male measurements were greater than those of the females. The study shows notable differences in the craniofacial parameters of the present sample as compared to other ancient Egyptians from various periods and from various geographical areas. Conclusion: The present study suggests that the studied crania from Bahriyah oasis had a specific craniometric phenotype, which is distinguished from other Egyptian samples from different periods, suggesting some migration could have occurred along the Egyptian Nile Valley over various times. PMID:23741149

SPE5 Sub-Scale Test Series Summary Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vandersall, Kevin S.; Reeves, Robert V.; DeHaven, Martin R.

2016-01-14

A series of 2 SPE5 sub-scale tests were performed to experimentally confirm that a booster system designed and evaluated in prior tests would properly initiate the PBXN-110 case charge fill. To conduct the experiments, a canister was designed to contain the nominally 50 mm diameter booster tube with an outer fill of approximately 150 mm diameter by 150 mm in length. The canisters were filled with PBXN-110 at NAWS-China Lake and shipped back to LLNL for testing in the High Explosives Applications Facility (HEAF). Piezoelectric crystal pins were placed on the outside of the booster tube before filling, and amore » series of piezoelectric crystal pins along with Photonic Doppler Velocimetry (PDV) probes were placed on the outer surface of the canister to measure the relative timing and magnitude of the detonation. The 2 piezoelectric crystal pins integral to the booster design were also utilized along with a series of either piezoelectric crystal pins or piezoelectric polymer pads on the top of the canister or outside case that utilized direct contact, gaps, or different thicknesses of RTV cushions to obtain time of arrival data to evaluate the response in preparation for the large-scale SPE5 test. To further quantify the margin of the booster operation, the 1st test (SPE5SS1) was functioned with both detonators and the 2nd test (SPE5SS2) was functioned with only 1 detonator. A full detonation of the material was observed in both experiments as observed by the pin timing and PDV signals. The piezoelectric pads were found to provide a greater measured signal magnitude during the testing with an RTV layer present, and the improved response is due to the larger measurement surface area of the pad. This report will detail the experiment design, canister assembly for filling, final assembly, experiment firing, presentation of the diagnostic results, and a discussion of the results.« less

Fecal incontinence, sexual complaints, and anorectal function after third-degree obstetric anal sphincter injury (OASI): 5-year follow-up.

PubMed

Visscher, A P; Lam, T J; Hart, N; Felt-Bersma, R J F

2014-05-01

Our aim was to evaluate alterations in anorectal function after anal sphincteroplasty for third-degree obstetric anal sphincter injury (OASI) in relation to clinical outcome. In this retrospective, descriptive, cross-sectional study conducted between 1998 and 2008, women with persisting fecal incontinence (FI) after 3a OASI and all women with grade 3b or 3c OASI were sent for anorectal function evaluation (AFE) consisting of anal manometry and endosonography 3 months after sphincteroplasty. In 2011, questionnaires regarding FI (Vaizey/Wexner), urinary incontinence (UI) [International Consultation on Incontinence Questionnaire Short Form (ICIQ-SF)], sexual function [Female Sexual Function Index (FSFI)], and quality of life (QOL) (Rand-36) were sent and women were asked to undergo additional AFE. Sixty-six women underwent AFE. Mean follow-up was 5.0 years. Forty (61%) patients returned questionnaires regarding FI and UI. Prevalence of FI was 63% flatus, 50% liquid stool, and 20% solid stool. Thirty-two of 40 also reported on QOL and SF. Sexual dysfunction was present in the majority of women (cutoff value 26.55) and more pronounced in larger OASI. Sixteen of 40 women underwent additional AFE. Women with combined internal (IAS) and external (EAS) anal sphincter injury (n = 6) had worse FI (P < 0.050) and lower anal pressures (P = 0.040) than women with isolated EAS injury (n = 10). Follow-up after third-degree OASI suggests poor anorectal and sexual function. Women with combined external and internal OASI show more deterioration in anorectal function and experience worse FI. Therefore, special attention should be paid to these women in order to mitigate these symptoms later in life.

Overdiagnosis and rising rate of obstetric anal sphincter injuries (OASIS): time for reappraisal.

PubMed

Sioutis, D; Thakar, R; Sultan, A H

2017-11-01

To determine the accuracy of clinical diagnosis of obstetric anal sphincter injuries (OASIS) using three-dimensional (3D) endoanal ultrasound (EA-US) and to compare symptoms and anal manometry measurements between women with anal sphincters adequately repaired and those with persistent anal sphincter defects. The EA-US images of women with clinically diagnosed and repaired OASIS, defined as third- or fourth-degree perineal tear, who attended the perineal clinic at Croydon University Hospital over a 10-year period (2003-2013) were reanalyzed by a single expert blind to symptoms and the results of clinical examination. St Mark's Incontinence Scores (SMIS) and anal manometry measurements were obtained and compared between women with an intact anal sphincter and those with an anal sphincter scar and between those with an intact anal sphincter and those with a defect. Anal manometry measurements were compared between women with an external anal sphincter (EAS) defect and those with an internal anal sphincter (IAS) defect. The images of 908 women were reanalyzed. No evidence of OASIS was found in 64 (7.0%) women, an EAS scar alone was detected in 520 (57.3%) and an anal sphincter defect in 324 (35.7%). Of the 324 women with a defect, 112 had an EAS defect, 90 had an IAS defect and 122 had a combined IAS and EAS defect. SMIS results were significantly higher in women with an anal sphincter defect compared with those with no evidence of OASIS (P = 0.018), but there was no significant difference in scores between women with an intact sphincter and those with an EAS scar only. Women with a defect had a significantly lower maximum resting pressure (median (range), 44 (8-106) vs 55 (29-86) mmHg; P < 0.001) and maximum squeeze pressure (median (range), 74 (23-180) vs 103 (44-185) mmHg; P < 0.001) compared with those in the intact group. Similar, but less marked, differences were observed in women with an EAS scar compared with those who had an intact anal sphincter

WINGS-SPE Spectroscopy in the WIde-field Nearby Galaxy-cluster Survey

NASA Astrophysics Data System (ADS)

Cava, A.; Bettoni, D.; Poggianti, B. M.; Couch, W. J.; Moles, M.; Varela, J.; Biviano, A.; D'Onofrio, M.; Dressler, A.; Fasano, G.; Fritz, J.; Kjærgaard, P.; Ramella, M.; Valentinuzzi, T.

2009-03-01

Aims: We present the results from a comprehensive spectroscopic survey of the WINGS (WIde-field Nearby Galaxy-cluster Survey) clusters, a program called WINGS-SPE. The WINGS-SPE sample consists of 48 clusters, 22 of which are in the southern sky and 26 in the north. The main goals of this spectroscopic survey are: (1) to study the dynamics and kinematics of the WINGS clusters and their constituent galaxies, (2) to explore the link between the spectral properties and the morphological evolution in different density environments and across a wide range of cluster X-ray luminosities and optical properties. Methods: Using multi-object fiber-fed spectrographs, we observed our sample of WINGS cluster galaxies at an intermediate resolution of 6-9 Å and, using a cross-correlation technique, we measured redshifts with a mean accuracy of ~45 km s-1. Results: We present redshift measurements for 6137 galaxies and their first analyses. Details of the spectroscopic observations are reported. The WINGS-SPE has ~30% overlap with previously published data sets, allowing us both to perform a complete comparison with the literature and to extend the catalogs. Conclusions: Using our redshifts, we calculate the velocity dispersion for all the clusters in the WINGS-SPE sample. We almost triple the number of member galaxies known in each cluster with respect to previous works. We also investigate the X-ray luminosity vs. velocity dispersion relation for our WINGS-SPE clusters, and find it to be consistent with the form Lx ∝ σ_v^4. Table 4, containing the complete redshift catalog, is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/495/707

Automated on-line renewable solid-phase extraction-liquid chromatography exploiting multisyringe flow injection-bead injection lab-on-valve analysis.

PubMed

Quintana, José Benito; Miró, Manuel; Estela, José Manuel; Cerdà, Víctor

2006-04-15

In this paper, the third generation of flow injection analysis, also named the lab-on-valve (LOV) approach, is proposed for the first time as a front end to high-performance liquid chromatography (HPLC) for on-line solid-phase extraction (SPE) sample processing by exploiting the bead injection (BI) concept. The proposed microanalytical system based on discontinuous programmable flow features automated packing (and withdrawal after single use) of a small amount of sorbent (<5 mg) into the microconduits of the flow network and quantitative elution of sorbed species into a narrow band (150 microL of 95% MeOH). The hyphenation of multisyringe flow injection analysis (MSFIA) with BI-LOV prior to HPLC analysis is utilized for on-line postextraction treatment to ensure chemical compatibility between the eluate medium and the initial HPLC gradient conditions. This circumvents the band-broadening effect commonly observed in conventional on-line SPE-based sample processors due to the low eluting strength of the mobile phase. The potential of the novel MSFI-BI-LOV hyphenation for on-line handling of complex environmental and biological samples prior to reversed-phase chromatographic separations was assessed for the expeditious determination of five acidic pharmaceutical residues (viz., ketoprofen, naproxen, bezafibrate, diclofenac, and ibuprofen) and one metabolite (viz., salicylic acid) in surface water, urban wastewater, and urine. To this end, the copolymeric divinylbenzene-co-n-vinylpyrrolidone beads (Oasis HLB) were utilized as renewable sorptive entities in the micromachined unit. The automated analytical method features relative recovery percentages of >88%, limits of detection within the range 0.02-0.67 ng mL(-1), and coefficients of variation <11% for the column renewable mode and gives rise to a drastic reduction in operation costs ( approximately 25-fold) as compared to on-line column switching systems.

Solid-phase extraction followed by liquid chromatography quadrupole time-of-flight tandem mass spectrometry for the selective determination of fungicides in wine samples.

PubMed

Fontana, A R; Rodríguez, I; Ramil, M; Altamirano, J C; Cela, R

2011-04-22

In this work, a reliable and selective procedure for the determination of thirteen fungicides in red and white wine samples is proposed. Solid-phase extraction (SPE) and liquid chromatography (LC) tandem mass spectrometry (MS/MS), based on a hybrid quadrupole time-of-flight (QTOF) system, were used as sample preparation and determination techniques, respectively. Extraction and purification of target analytes was carried out simultaneously by using a reversed-phase Oasis HLB (200mg) SPE cartridge combined with acetonitrile as elution solvent. Fungicides were determined operating the electrospray source in the positive ionization mode, with MS/MS conditions adjusted to obtain at least two intense product ions per compound, or registering two transitions per species when a single product was noticed. High selective MS/MS chromatograms were extracted using a mass window of 20 ppms for each product ion. Considering external calibration as quantification technique, the overall recoveries (accuracy) of the procedure ranged between 81% and 114% for red and white wine samples (10-20 mL), spiked at different concentrations between 5 and 100 ng mL(-1). Relative standard deviations of the above data stayed below 12% and the limits of quantification (LOQs) of the method, calculated for 10 mL of wine, varied between 0.1 ng mL(-1) for cyprodinil (CYP) and 0.7 ng mL(-1) for myclobutanil (MYC). The optimized method was applied to seventeen commercial wines produced in Spain and obtained from local supermarkets. Nine fungicides were determined, at levels above the LOQs of the method, in the above samples. The maximum concentrations and the highest occurrence frequencies corresponded to metalaxyl (MET) and iprovalicarb (IPR). Copyright © 2011 Elsevier B.V. All rights reserved.

Development and validation of a method for determination of corticosteroids in pig fat using liquid chromatography-tandem mass spectrometry.

PubMed

Tölgyesi, Adám; Sharma, Virender K; Fekete, Jeno

2011-02-15

A new method was developed to determine five corticosteroids (prednisolone, methylprednisone, flumethasone, dexamethasone, and methylprednisolone) in pig fat samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS) utilizing an optimized liquid-liquid extraction (LLE) and subsequent solid-phase extraction (SPE) for sample clean-up. In the sample preparation, a pig fat sample was dissolved in n-hexane and then extracted into the methanol-water (50/50, v/v) mixture that enabled extraction of only medium polar corticosteroids and not the non-polar components of matrices. This extract was cleaned-up and concentrated on polymeric Oasis HLB SPE cartridge. Separation involved isocratic solvent (methanol-acetate buffer, pH 5.4) and Ascentis Express Fused-Core type HLPC column; reduced the analysis time to 7.5 min, which is at least two times lower than time required for separation using conventional techniques. Other advantage of the developed method is the minimized ion suppression of LC-MS/MS analysis, which allowed detection of corticosteroids in sub μg/kg. Method was validated according to European Union (EU) Commission Decision 2002/657/EC. Measured parameters such as selectivity, linearity, recovery, within-laboratory reproducibility, decision limit, and detection capability satisfied the EU Directive. Ranges of mean recoveries and within-laboratory reproducibility were 81-100% and 8.0-20.5%, respectively. Decision limits were calculated in the range from 4.5 to 11.9 μg/kg for MRL compounds and varied from 0.1 to 0.2 μg/kg for banned substances. Limit of detections (LODs), calculated as three time signal-to-noise ratio, were in the range of 0.1-0.3 μg/kg. Copyright © 2010 Elsevier B.V. All rights reserved.

Gas chromatographic-mass spectrometric determination of alkylphosphonic acids from aqueous samples by ion-pair solid-phase extraction on activated charcoal and methylation.

PubMed

Vijaya Saradhi, U V R; Prabhakar, S; Jagadeshwar Reddy, T; Murty, M R V S

2007-07-20

In the present paper, we report an improved ion-pair solid-phase extraction (IP-SPE) method for the analysis of alkylphosphonic acids, namely, methyl, ethyl and propylphosphonic acids, present in the aqueous sample. The aqueous sample was mixed with an ion-pair reagent, phenyltrimethylammonium hydroxide (PTMAH) and passed through activated charcoal SPE cartridge. The retained chemicals in the cartridge were extracted with methanol and analysed by gas chromatography-mass spectrometry (GC-MS) under the electron impact ionization (EI) mode. The analytes were converted to their methyl esters by pyrolytic methylation in the hot GC injection port. The recoveries of alkylphosphonic acids were above 95% and the minimum detection limits were as low as 10 ng/mL. The recovery of the test chemicals was tested with solvents, dichloromethane, n-hexane, ethyl acetate, acetone, acetonitrile and methanol. The chemicals could be efficiently extracted by the hydrophilic solvents. The method did not work at the highly acidic pH (when acidified with dilute HCl) but worked well from pH 4.0 to 14.0. The present method was also tested with other tetra-(methyl, ethyl, propyl and n-butyl)ammonium hydroxides. The test chemicals were not converted to their methyl and ethyl esters with tetramethyl and tetraethylammonium hydroxides, whereas they were converted to their corresponding propyl and n-butyl esters with tetrapropyl and tetra(n-butyl)ammonium hydroxides. The method was also applied to two highly cross-linked polymeric sorbents DSC-6S and Oasis HLB. The recovery of the chemicals on these sorbents was observed to be poor. Methylation using phenyltrimethylammonium hydroxide is non-hazardous and advantageous over methylation using diazomethane. The method was applied to the analysis of aqueous samples given in one of the official proficiency tests conducted by the Organization for the Prohibition of Chemical Weapons and all the spiked chemicals were identified as methyl esters.

Comparison of Reduced Displacement Potentials from Spe Free Field Measurements: SPE-4PRIME Versus Previous Events

NASA Astrophysics Data System (ADS)

Patton, H. J.; Rougier, E.

2015-12-01

Since 2010, the U. S. Department of Energy has funded a series of chemical tests at the National Nuclear Security Site (NNSS) in Climax Stock granite as part of the Source Physics Experiment (SPE) with the aim of gaining a better understanding of the generation and propagation of seismic energy from underground explosions in hard rock media. To date, four tests have been conducted in the same borehole with yields of 100, 1000, 900 and 100 kg at different depths of burials. The nominal scaled depths of burial are 938, 363, 376 and 1556 m/kt1/3 compared to standard containment practices of ~120 m/kt1/3. A quite dense array of free field accelerometers were installed around the borehole, both on and off shot depth. Acceleration data were corrected for shock-generated baseline-shifts, and free field ground velocity waveforms were obtained. This work concentrates on the qualitative analysis of the reduced displacement potentials and the explosion source spectra for the last shot of the series (SPE-4Prime) and the comparison of the obtained results against the previous events. Finally, the results obtained from the experimental data are compared to the Mueller-Murphy empirical explosion model both using the Heard and Ackerman and Denny and Johnson cavity radius scaling laws.

Substrate-Induced Allosteric Change in the Quaternary Structure of the Spermidine N-Acetyltransferase SpeG.

PubMed

Filippova, Ekaterina V; Weigand, Steven; Osipiuk, Jerzy; Kiryukhina, Olga; Joachimiak, Andrzej; Anderson, Wayne F

2015-11-06

The spermidine N-acetyltransferase SpeG is a dodecameric enzyme that catalyzes the transfer of an acetyl group from acetyl coenzyme A to polyamines such as spermidine and spermine. SpeG has an allosteric polyamine-binding site and acetylating polyamines regulate their intracellular concentrations. The structures of SpeG from Vibrio cholerae in complexes with polyamines and cofactor have been characterized earlier. Here, we present the dodecameric structure of SpeG from V. cholerae in a ligand-free form in three different conformational states: open, intermediate and closed. All structures were crystallized in C2 space group symmetry and contain six monomers in the asymmetric unit cell. Two hexamers related by crystallographic 2-fold symmetry form the SpeG dodecamer. The open and intermediate states have a unique open dodecameric ring. This SpeG dodecamer is asymmetric except for the one 2-fold axis and is unlike any known dodecameric structure. Using a fluorescence thermal shift assay, size-exclusion chromatography with multi-angle light scattering, small-angle X-ray scattering analysis, negative-stain electron microscopy and structural analysis, we demonstrate that this unique open dodecameric state exists in solution. Our combined results indicate that polyamines trigger conformational changes and induce the symmetric closed dodecameric state of the protein when they bind to their allosteric sites. Copyright © 2015. Published by Elsevier Ltd.

Substrate-induced allosteric change in the quaternary structure of the spermidine N-acetyltransferase SpeG

DOE PAGES

Filippova, Ekaterina V.; Weigand, Steven J.; Osipiuk, Jerzy; ...

2015-09-26

The spermidine N-acetyltransferase SpeG is a dodecameric enzyme that catalyzes the transfer of an acetyl group from acetyl coenzyme A to polyamines such as spermidine and spermine. SpeG has an allosteric polyamine-binding site and acetylating polyamines regulate their intracellular concentrations. The structures of SpeG from Vibrio cholerae in complexes with polyamines and cofactor have been characterized earlier. Here, we present the dodecameric structure of SpeG from V. cholerae in a ligand-free form in three different conformational states: open, intermediate and closed. All structures were crystallized in C2 space group symmetry and contain six monomers in the asymmetric unit cell. Twomore » hexamers related by crystallographic 2-fold symmetry form the SpeG dodecamer. The open and intermediate states have a unique open dodecameric ring. This SpeG dodecamer is asymmetric except for the one 2-fold axis and is unlike any known dodecameric structure. Using a fluorescence thermal shift assay, size-exclusion chromatography with multi-angle light scattering, small-angle X-ray scattering analysis, negative-stain electron microscopy and structural analysis, we demonstrate that this unique open dodecameric state exists in solution. As a result, our combined results indicate that polyamines trigger conformational changes and induce the symmetric closed dodecameric state of the protein when they bind to their allosteric sites.« less

The sensibility of SPE induced atmospheric photochemical response to the ionization rate variations.

NASA Astrophysics Data System (ADS)

Krivolutsky, Alexei A.; Kukoleva, Anna; Kuminov, Alexander; Maygkova, Irina

During Solar proton event (SPE) energetic particles affect neutral atmospheric chemistry (Jackman et al. 1990, Krivolutsky A.A. et al. 2001 ets. ). The calculations results for [NO] and [O3] changes have qualitative suitability with observations data from satellites (UARS, HALOE for N.P.), although the simulated result differs in value from observed ones for nitrogen compounds. It seems potential probable reasons for this diversity exist. The sensibility of SPE induced atmospheric response to the ionization rates was investigated. The solar proton fluxes data from two satellites were used for ionization rate calculations by the method Vitt and Jackman (1996): geo-stationary GOES-10 (orbit height ≈ 40000 km) and CORONAS (orbit height is ≈ 400 km) for period of SPE 28.10. 2003. Calculated time integral ion creation during SPE using low and high orbit data differs for 1.5. Differences in ionization rate vertical distribution from GOES and CORONAS were found. Using this different ionization data the atmospherical composition response has been simulated with 1D photochemical model. The corresponding differences are discussed.

Development and validation of an HPLC-method for determination of free and bound phenolic acids in cereals after solid-phase extraction.

PubMed

Irakli, Maria N; Samanidou, Victoria F; Biliaderis, Costas G; Papadoyannis, Ioannis N

2012-10-01

Whole cereal grains are a good source of phenolic acids associated with reduced risk of chronic diseases. This paper reports the development and validation of a high-performance liquid chromatography-diode array detection (HPLC-DAD) method for the determination of phenolic acids in cereals in either free or bound form. Extraction of free phenolic acids and clean-up was performed by an optimised solid-phase extraction (SPE) protocol on Oasis HLB cartridges using aqueous methanol as eluant. The mean recovery of analytes ranged between 84% and 106%. Bound phenolic acids were extracted using alkaline hydrolysis with mean recoveries of 80-95%, except for gallic acid, caffeic acid and protocatechuic acid. Both free and bound phenolic extracts were separated on a Nucleosil 100 C18 column, 5 μm (250 mm × 4.6 mm) thermostated at 30 °C, using a linear gradient elution system consisting of 1% (v/v) acetic acid in methanol. Method validation was performed by means of linearity, accuracy, intra-day and inter-day precision and sensitivity. Detection limits ranged between 0.13 and 0.18 μg/g. The method was applied to the analysis of free and bound phenolic acids contents in durum wheat, bread wheat, barley, oat, rice, rye, corn and triticale. Copyright © 2012 Elsevier Ltd. All rights reserved.

Quantitation of slow release triptorelin in beagle dog plasma by liquid chromatography-tandem mass spectrometry.

PubMed

Han, Jiangbin; Sun, Jiye; Sha, Chunjie; Zhang, Jinfeng; Gai, Yunyun; Li, Youxin; Liu, Wanhui

2012-07-01

A sensitive method based on liquid chromatography-tandem mass spectrometry has been developed for the determination of triptorelin levels in beagle dog plasma. Plasma samples were applied to Oasis(®) HLB solid-phase extraction (SPE) cartridges. Extracted samples were evaporated under a stream of nitrogen and then reconstituted with 100 μl methanol:water:formic acid (60:40:0.08, v/v/v). The separation was achieved on a Venusil MP-C18 column (2.1 mm × 50 mm, 3 μm, Agela) with a gradient elution. Detection utilized a Qtrap5500 system operated in the positive ion mode with multiple reaction monitoring of the analyte at m/z 656.5→249.1 and of the I.S. at m/z 510.8→120.1. The proposed method was validated by assessing the specificity, linearity, precision and accuracy, recovery, matrix effects, and stability. Linear calibration curves were obtained in the concentration range of 0.01-10 ng/ml (the correlation coefficients were above 0.995). The lower limit of quantification (LLOQ) of the method was 0.01 ng/ml. The method was successfully applied to a pharmacokinetic study of a slow release triptorelin formulation in beagle dogs following a single intramuscular injection. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

Geohydrology of Monitoring Wells Drilled in Oasis Valley near Beatty, Nye County, Nevada, 1997

USGS Publications Warehouse

Robledo, Armando R.; Ryder, Philip L.; Fenelon, Joseph M.; Paillet, Frederick L.

1999-01-01

Twelve monitoring wells were installed in 1997 at seven sites in and near Oasis Valley, Nevada. The wells, ranging in depth from 65 to 642 feet, were installed to measure water levels and to collect water-quality samples. Well-construction data and geologic and geophysical logs are presented in this report. Seven geologic units were identified and described from samples collected during the drilling: (1) Ammonia Tanks Tuff; (2) Tuff of Cutoff Road; (3) tuffs, not formally named but informally referred to in this report as the 'tuff of Oasis Valley'; (4) lavas informally named the 'rhyolitic lavas of Colson Pond'; (5) Tertiary colluvial and alluvial gravelly deposits; (6) Tertiary and Quaternary colluvium; and (7) Quaternary alluvium. Water levels in the wells were measured in October 1997 and February 1998 and ranged from about 18 to 350 feet below land surface. Transmissive zones in one of the boreholes penetrating volcanic rock were identified using flowmeter data. Zones with the highest transmissivity are at depths of about 205 feet in the 'rhyolitic lavas of Colson Pond' and 340 feet within the 'tuff of Oasis Valley.'

Oasis deposits in the southern margin of the Taklimakan Desert and abrupt environmental changes during the last 30 ka

NASA Astrophysics Data System (ADS)

Shu, P.; Li, B.; Wang, H.; Cheng, P.; An, Z.; Zhou, W.; Zhang, D. D.

2017-12-01

Taklimakan Desert, the largest arid landform in the Eurasia, is one of the most important dust sources in the world. Growing evidences shows that millennial-scale abrupt climate changes during the last glacial period in the region. However, records on millennial-scale climate and environmental changes remain poorly understood because dating eolian, lacustrine, and fluvial sediments and establishing the reliable environmental proxies from these records are always challenging. Here, we present 32 AMS 14C dates of bulk sediments, grain size, and Rb/Sr ratio parameters from the oasis sequence and dates of bulk loess and charcoal from the upstream source regions to examine the significance of oasis sediments on millennial-scale environmental changes in the Taklimakan Desert. We found that substantial reversal of radiocarbon dates on total organic carbon (TOC) was controlled by source region organic carbon input. Loess hills, alpine meadow north of the study region provided fluvial deposits along drainage system and deflation in the river valleys further provide eolain materials. We argue that early oasis deposits experienced deflation and re-deposition less severe than the younger oasis deposits. After refining radiocarbon age-depth relationships for an age model by Bacon package, proxy records show substantial abrupt fluctuations in climate and environments during the last glacial period, among which three wet intervals, two dry periods are identified. The wetter and warmer conditions during the Holocene facilitated human to occupy the oasis.

Spacecraft Solar Particle Event (SPE) Shielding: Shielding Effectiveness as a Function of SPE Model as Determined with the FLUKA Radiation Transport Code

NASA Astrophysics Data System (ADS)

Koontz, S. L.; Atwell, W. A.; Reddell, B.; Rojdev, K.

2010-12-01

In the this paper, we report the results of modeling and simulation studies in which the radiation transport code FLUKA (FLUktuierende KAskade) is used to determine the changes in total ionizing dose (TID) and single-event effect (SEE) environments behind aluminum, polyethylene, carbon, and titanium shielding masses when the assumed form (i.e., Band or Exponential) of the solar particle event (SPE) kinetic energy spectra is changed. FLUKA simulations are fully three dimensional with an isotropic particle flux incident on a concentric spherical shell shielding mass and detector structure. FLUKA is a fully integrated and extensively verified Monte Carlo simulation package for the interaction and transport of high-energy particles and nuclei in matter. The effects are reported of both energetic primary protons penetrating the shield mass and secondary particle showers caused by energetic primary protons colliding with shielding mass nuclei. SPE heavy ion spectra are not addressed. Our results, in agreement with previous studies, show that use of the Exponential form of the event spectra can seriously underestimate spacecraft SPE TID and SEE environments in some, but not all, shielding mass cases. The SPE spectra investigated are taken from four specific SPEs that produced ground-level events (GLEs) during solar cycle 23 (1997-2008). GLEs are produced by highly energetic solar particle events (ESP), i.e., those that contain significant fluences of 700 MeV to 10 GeV protons. Highly energetic SPEs are implicated in increased rates of spacecraft anomalies and spacecraft failures. High-energy protons interact with Earth’s atmosphere via nuclear reaction to produce secondary particles, some of which are neutrons that can be detected at the Earth’s surface by the global neutron monitor network. GLEs are one part of the overall SPE resulting from a particular solar flare or coronal mass ejection event on the sun. The ESP part of the particle event, detected by spacecraft

18 CFR 37.6 - Information to be posted on the OASIS.

Code of Federal Regulations, 2011 CFR

2011-04-01

... protocols, information regarding the transmission system necessary to enable prudent business decision... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY...

18 CFR 37.6 - Information to be posted on the OASIS.

Code of Federal Regulations, 2010 CFR

2010-04-01

... protocols, information regarding the transmission system necessary to enable prudent business decision... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY...

Interference of a speB 5' untranslated region partial deletion with mRNA degradation in Streptococcus pyogenes.

PubMed

Chen, Z; Mashburn-Warren, L; Merritt, J; Federle, M J; Kreth, J

2017-10-01

The 5' untranslated region (5' UTR) of an mRNA molecule embeds important determinants that modify its stability and translation efficiency. In Streptococcus pyogenes, a strict human pathogen, a gene encoding a secreted protease (speB) has a large 5' UTR with unknown functions. Here we describe that a partial deletion of the speB 5' UTR caused a general accumulation of mRNA in the stationary phase, and that the mRNA accumulation was due to retarded mRNA degradation. The phenotype was observed in several M serotypes harboring the partial deletion of the speB 5' UTR. The phenotype was triggered by the production of the truncated speB 5' UTR, but not by the disruption of the intact speB 5' UTR. RNase Y, a major endoribonuclease, was previously shown to play a central role in bulk mRNA turnover in stationary phase. However, in contrast to our expectations, we observed a weaker interaction between the truncated speB 5' UTR and RNase Y compared with the wild-type, which suggests that other unidentified RNA degrading components are required for the pleiotropic effects observed from the speB UTR truncation. Our study demonstrates how S. pyogenes uses distinct mRNA degradation schemes in exponential and stationary growth phases. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Ground-water discharge determined from measurements of evapotranspiration, other available hydrologic components, and shallow water-level changes, Oasis Valley, Nye County, Nevada

USGS Publications Warehouse

Reiner, S.R.; Laczniak, R.J.; DeMeo, G.A.; Smith, J. LaRue; Elliott, P.E.; Nylund, W.E.; Fridrich, C.J.

2002-01-01

Oasis Valley is an area of natural ground-water discharge within the Death Valley regional ground-water flow system of southern Nevada and adjacent California. Ground water discharging at Oasis Valley is replenished from inflow derived from an extensive recharge area that includes the northwestern part of the Nevada Test Site (NTS). Because nuclear testing has introduced radionuclides into the subsurface of the NTS, the U.S. Department of Energy currently is investigating the potential transport of these radionuclides by ground water flow. To better evaluate any potential risk associated with these test-generated contaminants, a number of studies were undertaken to accurately quantify discharge from areas downgradient in the regional ground-water flow system from the NTS. This report refines the estimate of ground-water discharge from Oasis Valley. Ground-water discharge from Oasis Valley was estimated by quantifying evapotranspiration (ET), estimating subsurface outflow, and compiling ground-water withdrawal data. ET was quantified by identifying areas of ongoing ground-water ET, delineating areas of ET defined on the basis of similarities in vegetation and soil-moisture conditions, and computing ET rates for each of the delineated areas. A classification technique using spectral-reflectance characteristics determined from satellite imagery acquired in 1992 identified eight unique areas of ground-water ET. These areas encompass about 3,426 acres of sparsely to densely vegetated grassland, shrubland, wetland, and open water. Annual ET rates in Oasis Valley were computed with energy-budget methods using micrometeorological data collected at five sites. ET rates range from 0.6 foot per year in a sparse, dry saltgrass environment to 3.1 feet per year in dense meadow vegetation. Mean annual ET from Oasis Valley is estimated to be about 7,800 acre-feet. Mean annual ground-water discharge by ET from Oasis Valley, determined by removing the annual local precipitation

Preliminary SPE Phase II Far Field Ground Motion Estimates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steedman, David W.

2014-03-06

Phase II of the Source Physics Experiment (SPE) program will be conducted in alluvium. Several candidate sites were identified. These include existing large diameter borehole U1e. One criterion for acceptance is expected far field ground motion. In June 2013 we were requested to estimate peak response 2 km from the borehole due to the largest planned SPE Phase II experiment: a contained 50- Ton event. The cube-root scaled range for this event is 5423 m/KT 1/3. The generally accepted first order estimate of ground motions from an explosive event is to refer to the standard data base for explosive eventsmore » (Perrett and Bass, 1975). This reference is a compilation and analysis of ground motion data from numerous nuclear and chemical explosive events from Nevada National Security Site (formerly the Nevada Test Site, or NTS) and other locations. The data were compiled and analyzed for various geologic settings including dry alluvium, which we believe is an accurate descriptor for the SPE Phase II setting. The Perrett and Bass plots of peak velocity and peak yield-scaled displacement, both vs. yield-scaled range, are provided here. Their analysis of both variables resulted in bi-linear fits: a close-in non-linear regime and a more distant linear regime.« less

Recent advances in SPE (tm) water electrolyzer

NASA Technical Reports Server (NTRS)

Mcelroy, James F.

1993-01-01

A new cell structure has been introduced into the SPE Water Electrolyzer which has improved overall characteristics significantly. Weight, reliability, and efficiency are the characteristics that are improved the most, with volume having a second order improvement. This paper discusses the capabilities of the new cell structure and the impact it would have in various space applications.

Solar thermotherapy reduces the titer of ‘Candidatus Liberibacter asiaticus’ while enhancing canopy growth in HLB-affected residential and commercial citrus

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB), a systemic and destructive disease of citrus, is associated with three species of a-proteobacteria, ‘Candidatus Liberibacter asiaticus’ (Las), ‘Ca. L. africanus’ and ‘Ca. L. americanus’. Previous studies have found distinct variations in temperature sensitivity and tolerance amo...

Electronic Tongue Response to Chemicals in Orange Juice that Change Concentration in Relation to Harvest Maturity and Citrus Greening or Huanglongbing (HLB) Disease.

PubMed

Raithore, Smita; Bai, Jinhe; Plotto, Anne; Manthey, John; Irey, Mike; Baldwin, Elizabeth

2015-12-02

In an earlier study, an electronic tongue system (e-tongue) has been used to differentiate between orange juice made from healthy fruit and from fruit affected by the citrus greening or Huanglongbing (HLB) disease. This study investigated the reaction of an e-tongue system to the main chemicals in orange juice that impact flavor and health benefits and are also impacted by HLB. Orange juice was spiked with sucrose (0.2-5.0 g/100 mL), citric acid (0.1%-3.0% g/100 mL) and potassium chloride (0.1-3.0 g/100 mL) as well as the secondary metabolites nomilin (1-30 µg/mL), limonin (1-30 µg/mL), limonin glucoside (30-200 µg/mL), hesperidin (30-400 µg/mL) and hesperetin (30-400 µg/mL). Performance of Alpha MOS sensor sets #1 (pharmaceutical) and #5 (food) were compared for the same samples, with sensor set #1 generally giving better separation than sensor set #5 for sucrose, sensor set #5 giving better separation for nomilin and limonin, both sets being efficient at separating citric acid, potassium chloride, hesperitin and limonin glucoside, and neither set discriminating hesperidin efficiently. Orange juice made from fruit over the harvest season and from fruit harvested from healthy or HLB-affected trees were separated by harvest maturity, disease state and disease severity.

Time-Dependent Moment Tensors of the First Four Source Physics Experiments (SPE) Explosions

NASA Astrophysics Data System (ADS)

Yang, X.

2015-12-01

We use mainly vertical-component geophone data within 2 km from the epicenter to invert for time-dependent moment tensors of the first four SPE explosions: SPE-1, SPE-2, SPE-3 and SPE-4Prime. We employ a one-dimensional (1D) velocity model developed from P- and Rg-wave travel times for Green's function calculations. The attenuation structure of the model is developed from P- and Rg-wave amplitudes. We select data for the inversion based on the criterion that they show consistent travel times and amplitude behavior as those predicted by the 1D model. Due to limited azimuthal coverage of the sources and the mostly vertical-component-only nature of the dataset, only long-period, diagonal components of the moment tensors are well constrained. Nevertheless, the moment tensors, particularly their isotropic components, provide reasonable estimates of the long-period source amplitudes as well as estimates of corner frequencies, albeit with larger uncertainties. The estimated corner frequencies, however, are consistent with estimates from ratios of seismogram spectra from different explosions. These long-period source amplitudes and corner frequencies cannot be fit by classical P-wave explosion source models. The results motivate the development of new P-wave source models suitable for these chemical explosions. To that end, we fit inverted moment-tensor spectra by modifying the classical explosion model using regressions of estimated source parameters. Although the number of data points used in the regression is small, the approach suggests a way for the new-model development when more data are collected.

The influence of surfactant HLB and oil/surfactant ratio on the formation and properties of self-emulsifying pellets and microemulsion reconstitution.

PubMed

Matsaridou, Irini; Barmpalexis, Panagiotis; Salis, Andrea; Nikolakakis, Ioannis

2012-12-01

Self-emulsifying oil/surfactant mixtures can be incorporated into pellets that have the advantages of the oral administration of both microemulsions and a multiple-unit dosage form. The purpose of this work was to study the effects of surfactant hydrophilic-lipophilic balance (HLB) and oil/surfactant ratio on the formation and properties of self-emulsifying microcrystalline cellulose (MCC) pellets and microemulsion reconstitution. Triglycerides (C(8)-C(10)) was the oil and Cremophor ELP and RH grades and Solutol the surfactants. Pellets were prepared by extrusion/spheronization using microemulsions with fixed oil/surfactant content but with different water proportions to optimize size and shape parameters. Microemulsion reconstitution from pellets suspended in water was evaluated by turbidimetry and light scattering size analysis, and H-bonding interactions of surfactant with MCC from FT-IR spectra. It was found that water requirements for pelletization increased linearly with increasing HLB. Crushing load decreased and deformability increased with increasing oil/surfactant ratio. Incorporation of higher HLB surfactants enhanced H-bonding and resulted in faster and more extensive disintegration of MCC as fibrils. Reconstitution was greater at high oil/surfactant ratios and the droplet size of the reconstituted microemulsions was similar to that in the wetting microemulsions. The less hydrophilic ELP with a double bond in the fatty acid showed weaker H-bonding and greater microemulsion reconstitution. Purified ELP gave greater reconstitution than the unpurified grade. Thus, the work demonstrates that the choice of type and quantity of the surfactant used in the formulation of microemulsions containing pellets has an important influence on their production and performance.

OASIS - ORBIT ANALYSIS AND SIMULATION SOFTWARE

NASA Technical Reports Server (NTRS)

Wu, S. C.

1994-01-01

The Orbit Analysis and Simulation Software, OASIS, is a software system developed for covariance and simulation analyses of problems involving earth satellites, especially the Global Positioning System (GPS). It provides a flexible, versatile and efficient accuracy analysis tool for earth satellite navigation and GPS-based geodetic studies. To make future modifications and enhancements easy, the system is modular, with five major modules: PATH/VARY, REGRES, PMOD, FILTER/SMOOTHER, and OUTPUT PROCESSOR. PATH/VARY generates satellite trajectories. Among the factors taken into consideration are: 1) the gravitational effects of the planets, moon and sun; 2) space vehicle orientation and shapes; 3) solar pressure; 4) solar radiation reflected from the surface of the earth; 5) atmospheric drag; and 6) space vehicle gas leaks. The REGRES module reads the user's input, then determines if a measurement should be made based on geometry and time. PMOD modifies a previously generated REGRES file to facilitate various analysis needs. FILTER/SMOOTHER is especially suited to a multi-satellite precise orbit determination and geodetic-type problems. It can be used for any situation where parameters are simultaneously estimated from measurements and a priori information. Examples of nonspacecraft areas of potential application might be Very Long Baseline Interferometry (VLBI) geodesy and radio source catalogue studies. OUTPUT PROCESSOR translates covariance analysis results generated by FILTER/SMOOTHER into user-desired easy-to-read quantities, performs mapping of orbit covariances and simulated solutions, transforms results into different coordinate systems, and computes post-fit residuals. The OASIS program was developed in 1986. It is designed to be implemented on a DEC VAX 11/780 computer using VAX VMS 3.7 or higher. It can also be implemented on a Micro VAX II provided sufficient disk space is available.

[Landscape pattern and productivity characteristics of the oasis landscape ecosystem in Linze, Gansu, China].

PubMed

Liu, Xuelu; Ren, Jizhou; Zhang, Zihe

2002-08-01

Oasis landscape ecosystem is composed of 10 landscape elements, i.e., residence land, cultivated land, grassland, forestland, water area, water system, road, rocky desert, sandy desert, and gravel desert. Among the elements, cultivated land formed by human being production covers the most of the area, is most connected, and hence, is the matrix of the oasis landscape ecosystem. Residence land, grassland, forestland, water area, rocky desert, sandy desert, and gravel desert are patches. Residence land and forestland generate from human being production, while rocky desert, gravel desert and sandy desert are the remnant with the human being disturbance. Water region and grassland are the environmental resources remnant after natural disturbance. Water system and road are corridors. Cultivated land dominated in plant production should be utilized with more productive layers through developing animal production other than expanding used-area to maintain the landscape heterogeneity and diversity of the oasis landscape ecosystem. For remnant and environmental resource patches, it should be profitable in preserving and stabilizing landscape heterogeneity and diversity, exploiting the functions of water and soil conservation, tourism, windbreak and sand fixation. For landscape elements remnant only, it should be fruitful in avoiding degeneration of the landscape pattern to explore their preceding plant production with moderate plant production.

Development of consumer-friendly transgenic citrus plants with potential broad spectrum resistance to HLB, Citrus canker, Phytopthora and other exotic diseases

USDA-ARS?s Scientific Manuscript database

The second year of this CRB funded project has started, which is focused on the development of citrus cultivars that exhibit disease resistance to multiple pathogens such as HLB, Phytophthora and citrus canker diseases. We are using precise genetic engineering to introduce into disease susceptible ...

Autonomous Monitoring of Radiation Environment and Personal Systems for Crew Enhanced SPE Protection (AMORE and PSYCHE)

NASA Astrophysics Data System (ADS)

Narici, L.; Baiocco, G.; Berrilli, F.; Giraudo, M.; Ottolenghi, A.; Rizzo, A.; Salina, G.

2018-02-01

Understand the relationship between SPE precursors, the related SPE radiation inside the Deep Space Gateway, and the associated risk levels, validating existing models, proposing countermeasures actions via a real time, autonomous intelligent system.

18 CFR 37.6 - Information to be posted on the OASIS.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME...

18 CFR 37.6 - Information to be posted on the OASIS.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME...

18 CFR 37.6 - Information to be posted on the OASIS.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME...

In Situ Miniaturised Solid Phase Extraction (m-SPE) for Organic Pollutants in Seawater Samples

PubMed Central

Abaroa-Pérez, B.; Sánchez-Almeida, G.; Hernández-Brito, J. J.

2018-01-01

Solid phase extraction (SPE) is a consolidated technique for determining pollutants in seawater samples. The current tendency is to miniaturise systems that extract and determine pollutants in the environment, reducing the use of organic solvents, while maintaining the quality in the extraction and preconcentration. On the other hand, there is a need to develop new extraction systems that can be fitted to in situ continual monitoring buoys, especially for the marine environment. This work has developed a first model of a low-pressure micro-SPE (m-SPE) for persistent organic pollutants (POPs) that can be simply applied to in situ monitoring in the marine environment. This system reduces the volumes of sample and solvents required in the laboratory in comparison with conventional SPE. In the future, it could be used in automated or robotic systems in marine technologies such as marine gliders and oceanographic buoys. This system has been optimised and validated to determine polycyclic aromatic hydrocarbons (PAH) in seawater samples, but it could also be applied to other kinds of persistent organic pollutants (POPs) and emerging pollutants. PMID:29805837

Theory of stability, and regulation and control of ecological system in oasis

NASA Astrophysics Data System (ADS)

Pan, Xiaoling; Chao, Jiping

2003-06-01

Starting with analysis on the evolving course of oasis and the characteristics and evolution of transitional zone between oasis and desert, in consideration of ecological elements including plant stomata resistance, area covered by vegetation, and physical elements including albedo of vegetation and bare soil, atmosphere temperature, and humidity, under the condition of the balance among net radiation flux, latent heat flux, and sensible heat flux, the following are calculated: temperatures of vegetation and bare soil in different conditions, as well as the evapotranspiration rate of ecosystem. Analysis on evapotranspiration rate indicates that it depends on both the climate of environment and the physiological and ecological conditions of plants. On certain conditions, the evapotranspiration rate of transitional zone between oasis and desert (i.e. area covered by vegetation less than 20%), in some parameter domains, appears in bifurcation or multiequilibrium state. Meanwhile, in such area, ecosystem is extremely unstable. Any minor change to the balance will cause either increase or reduction of area covered by vegetation in ecosystem, on the basis of discussion on the emergency of these phenomena. This paper is attempting to propose an effective way of destruction and rebuilt ecosystem in transitional zone. The way is to control the evaporation of plant through selecting anti-drought country plant with big stomata resistance, and modify the roughness of the underlying surface in ecosystem by establishing rational interspace structure of plant community, so as to put the degenerative ecosystem into the natural succession track. This primary theory is being verified through observation and analysis on historical data.

A Modified LC/MS/MS Method with Enhanced Sensitivity for the Determination of Scopolamine in Human Plasma

NASA Technical Reports Server (NTRS)

Wang, Zuwei; Vaksman, Zalman; Putcha, Lakshmi

2008-01-01

Intranasal scopolamine is a choice drug for the treatment of motion sickness during space flight because of its quick onset of action, short half-life and favorable sideeffects profile. The dose administered usually ranges between 0.1 and 0.4 mg. Such small doses make it difficult to detect concentrations of scopolamine in biological fluids using existing sensitive LC/MS/MS method, especially when the biological sample volumes are limited. To measure scopolamine in human plasma to facilitate pharmacokinetic evaluation of the drug, we developed a sensitive LC/MS/MS method using 96 well micro elution plates for solid phase extraction (SPE) of scopolamine in human plasma. Human plasma (100-250 micro L) were loaded onto Waters Oasis HLB 96 well micro elution plate and eluted with 50 L of organic solvent without evaporation and reconstitution. HPLC separation of the eluted sample was performed using an Agilent Zorbax SB-CN column (50 x 2.1 mm) at a flow rate of 0.2 mL/min for 3 minutes. The mobile phase for separation was 80:20 (v/v) methanol: ammonium acetate (30 mM) in water. Concentrations of scopolamine were determined using a Micromass Quattro Micro(TM) mass spectrometer with electrospray ionization (ESI). ESI mass spectra were acquired in positive ion mode with multiple reaction monitoring for the determination of scopolamine m/z = 304.2 right arrow 138.1 and internal standard hyoscyamine m/z = 290.2 right arrow 124.1. The method is rapid, reproducible, specific and has the following parameters: scopolamine and the IS are eluted at about 1.1 and 1.7 min respectively. The linear range is 25-10000 pg/mL for scopolamine in human plasma with correlation coefficients greater than 0.99 and CV less than 0.5%. The intra-day and inter-day CVs are less than 15% for quality control samples with concentrations of 75,300, and 750 pg/mL of scopolamine in human plasma. SPE using 96 well micro elution plates allows rapid sample preparation and enhanced sensitivity for the LC

SPE (trademark) Oxygen Generator Assembly (OGA). (Refurbishment of the technology demonstrator LFSPE oxygen generation subsystem)

NASA Technical Reports Server (NTRS)

Roy, Robert J.

1995-01-01

The SPE Oxygen Generator Assembly (OGA) has been modified to correct operational deficiencies present in the original system, and to effect changes to the system hardware and software such that its operating conditions are consistent with the latest configuration requirements for the International Space Station Alpha (ISSA). The effectiveness of these changes has recently been verified through a comprehensive test program which saw the SPE OGA operate for over 740 hours at various test conditions, including over 690 hours, or approximately 460 cycles, simulating the orbit of the space station. This report documents the changes made to the SPE OGA, presents and discusses the test results from the acceptance test program, and provides recommendations for additional development activities pertinent to evolution of the SPE OGA to a flight configuration. Copies of the test data from the acceptance test program are provided with this report on 3.5 inch diskettes in self-extracting archive files.

A novel polyamine allosteric site of SpeG from Vibrio cholerae is revealed by its dodecameric structure

PubMed Central

Filippova, Ekaterina V.; Kuhn, Misty L.; Osipiuk, Jerzy; Kiryukhina, Olga; Joachimiak, Andrzej; Ballicora, Miguel A.

2015-01-01

Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence of a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase (GNAT) superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key towards understanding the regulation of polyamine levels in bacteria during pathogenesis. PMID:25623305

Electronic Tongue Response to Chemicals in Orange Juice that Change Concentration in Relation to Harvest Maturity and Citrus Greening or Huanglongbing (HLB) Disease

PubMed Central

Raithore, Smita; Bai, Jinhe; Plotto, Anne; Manthey, John; Irey, Mike; Baldwin, Elizabeth

2015-01-01

In an earlier study, an electronic tongue system (e-tongue) has been used to differentiate between orange juice made from healthy fruit and from fruit affected by the citrus greening or Huanglongbing (HLB) disease. This study investigated the reaction of an e-tongue system to the main chemicals in orange juice that impact flavor and health benefits and are also impacted by HLB. Orange juice was spiked with sucrose (0.2–5.0 g/100 mL), citric acid (0.1%–3.0% g/100 mL) and potassium chloride (0.1–3.0 g/100 mL) as well as the secondary metabolites nomilin (1–30 µg/mL), limonin (1–30 µg/mL), limonin glucoside (30–200 µg/mL), hesperidin (30–400 µg/mL) and hesperetin (30–400 µg/mL). Performance of Alpha MOS sensor sets #1 (pharmaceutical) and #5 (food) were compared for the same samples, with sensor set #1 generally giving better separation than sensor set #5 for sucrose, sensor set #5 giving better separation for nomilin and limonin, both sets being efficient at separating citric acid, potassium chloride, hesperitin and limonin glucoside, and neither set discriminating hesperidin efficiently. Orange juice made from fruit over the harvest season and from fruit harvested from healthy or HLB-affected trees were separated by harvest maturity, disease state and disease severity. PMID:26633411

Quantification of the impacts of climate change and human agricultural activities on oasis water requirements in an arid region: a case study of the Heihe River basin, China

NASA Astrophysics Data System (ADS)

Liu, Xingran; Shen, Yanjun

2018-03-01

Ecological deterioration in arid regions caused by agricultural development has become a global issue. Understanding water requirements of the oasis ecosystems and the influences of human agricultural activities and climate change is important for the sustainable development of oasis ecosystems and water resource management in arid regions. In this study, water requirements of the main oasis in Heihe River basin during 1986-2013 were analyzed and the amount showed a sharp increase from 10.8 × 108 m3 in 1986 to 19.0 × 108 m3 in 2013. Both human agricultural activities and climate change could lead to the increase in water requirement. To quantify the contributions of agricultural activities and climate change to the increase in water requirements, partial derivative and slope method were used. Results showed that climate change and human agricultural activities, such as oasis expansion and changes in land cropping structure, has contributed to the increase in water requirement at rates of 6.9, 58.1, and 25.3 %, respectively. Overall, human agricultural activities were the dominant forces driving the increase in water requirement. In addition, the contribution of oasis expanding to the increased water requirement was significantly greater than that of other concerned variables. This reveals that controlling the oasis scale is extremely important and effective for balancing water for agriculture and ecosystems and to achieving a sustainable oasis development in arid regions.

On-line MSPD-SPE-HPLC/FLD analysis of polycyclic aromatic hydrocarbons in bovine tissues.

PubMed

Gutiérrez-Valencia, Tania M; García de Llasera, Martha P

2017-05-15

A fast method was optimized and validated for simultaneous trace determination of four polycyclic aromatic hydrocarbons: benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene and benzo[a]pyrene in bovine tissues. The determination was performed by matrix solid-phase dispersion (MSPD) coupled on-line to solid phase extraction (SPE) and high performance liquid chromatography (HPLC) with fluorescence detection (FLD). The sample was dispersed on C 18 silica sorbent and then the on-line MSPD-SPE-HPLC/FLD method was applied. Several parameters were optimized: cleaning and elution sequences applied to the MSPD cartridge, the flow rate and dilution of extract used for SPE loading. The on-line method was validated over a concentration range of 0.1-0.6ngg -1 obtaining good linearity (r⩾0.998) and precision (RSD)⩽10%. Recovery ranged from 96 to 99% and the limits of detection were 0.012ngg -1 . This methodology was applied to liver samples from unhealthy animals. The results demonstrate that MSDP-SPE-HPLC/FLD method provides reliable, sensitive, accurate and fast data to the food control. Copyright © 2016 Elsevier Ltd. All rights reserved.

A novel polyamine allosteric site of SpeG from Vibrio cholerae is revealed by Its dodecameric structure

DOE PAGES

Filippova, Ekaterina V.; Kuhn, Misty L.; Osipiuk, Jerzy; ...

2015-01-23

Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence ofmore » a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key toward understanding the regulation of polyamine levels in bacteria during pathogenesis.« less

A novel polyamine allosteric site of SpeG from Vibrio cholerae is revealed by Its dodecameric structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Filippova, Ekaterina V.; Kuhn, Misty L.; Osipiuk, Jerzy

Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence ofmore » a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key toward understanding the regulation of polyamine levels in bacteria during pathogenesis.« less

A novel polyamine allosteric site of SpeG from Vibrio cholerae is revealed by its dodecameric structure.

PubMed

Filippova, Ekaterina V; Kuhn, Misty L; Osipiuk, Jerzy; Kiryukhina, Olga; Joachimiak, Andrzej; Ballicora, Miguel A; Anderson, Wayne F

2015-03-27

Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence of a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key toward understanding the regulation of polyamine levels in bacteria during pathogenesis. Copyright © 2015. Published by Elsevier Ltd.

Development of an ultra-high-pressure liquid chromatography-tandem mass spectrometry multi-residue sulfonamide method and its application to water, manure slurry, and soils from swine rearing facilities.

PubMed

Shelver, Weilin L; Hakk, Heldur; Larsen, Gerald L; DeSutter, Thomas M; Casey, Francis X M

2010-02-19

An analytical method was developed using ultra-high-pressure liquid chromatography-triple quadrupole-tandem mass spectrometry (UHPLC-TQ-MS/MS) to simultaneously analyze 14 sulfonamides (SA) in 6 min. Despite the rapidity of the assay the system was properly re-equilibrated in this time. No carryover was observed even after high analyte concentrations. The instrumental detection limit based on signal-to-noise ratio (S/N)>3, was below 1 pg/microL (5 pg on column) for all SAs except sulfachloropyridazine. Surface water, ground water, soil, and slurry manure contained in storage ponds in and around swine [Sus scrofa domesticus] rearing facilities were analyzed. Sample cleanup for ground water and surface water included using solid phase extraction (SPE) using Oasis hydrophilic-lipophilic balance (HLB) cartridges. The soil and slurry manure required tandem strong anion exchange (SAX) and HLB solid phase extraction cartridges for sample cleanup. With few exceptions, the recoveries ranged from 60 to 100% for all matrices. The minimum detectable levels were below 2.0 ng/L for water, 30 ng/L for slurry manure, and 45 ng/kg for soil except for sulfachloropyridazine. The coefficient of variation (CV) was within 20% for most of the compounds analyzed. Using this method, sulfamethazine concentrations of 2250-5060 ng/L, sulfamethoxazole concentrations of 108-1.47 x 10(6)ng/L, and sulfathiazole concentrations of 785-1700 ng/L were found in the slurry manure. Sulfadimethoxine (2.0-32 ng/L), sulfamethazine (2.0-5.1 ng/L), and sulfamethoxazole (20.5-43.0 ng/L) were found in surface water and ground water. In top soil (0-15 cm), sulfamethazine ranged 34.5-663 ng/kg dry weight in those locations that received slurry manure as a nutrient; no SAs were found in the soil depths between 46 and 61 cm. The speed makes the method practical for medium to high throughput applications. The sensitivity and positive analyte identification make the method suitable for the demanding requirements for

Apparent Explosion Moments from Rg Waves Recorded on SPE

DOE PAGES

Larmat, Carene; Rougier, Esteban; Patton, Howard John

2016-11-29

Seismic moments for the first four chemical tests making up phase I of the Source Physics Experiments (SPE) are estimated from 6-Hz Rg waves recorded along a single radial line of geophones under the assumption that the tests are pure explosions. These apparent explosion moments are compared with moments determined from the reduced displacement potential method applied to free-field data. Light detection and ranging (lidar) observations, strong ground motions on the free surface in the vicinity of ground zero, and moment tensor inversion results are evidence that the fourth test SPE-4P is a pure explosion, and the moments show goodmore » agreement, 8×10 10 N·m for free-field data versus 9×10 10 N·m for Rg waves. In stark contrast, apparent moments for the first three tests are smaller than near-field moments by factors of 3–4. Relative amplitudes for the three tests determined from Rg interferometry using SPE-4P as an empirical Green’s function indicate that radiation patterns are cylindrically symmetric within a factor of 1.25 (25%). This fact assures that the apparent moments are reliable even though they were measured on just one azimuth. Spallation occurred on the first three tests, and ground-based lidar detected permanent deformations. As such, the source medium suffered late-time damage. In conclusion, destructive interference between Rg waves radiated by explosion and damage sources will reduce amplitudes and explain why apparent moments are smaller than near-field moments based on compressional energy emitted directly from the source.« less

Apparent Explosion Moments from Rg Waves Recorded on SPE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Larmat, Carene; Rougier, Esteban; Patton, Howard John

Seismic moments for the first four chemical tests making up phase I of the Source Physics Experiments (SPE) are estimated from 6-Hz Rg waves recorded along a single radial line of geophones under the assumption that the tests are pure explosions. These apparent explosion moments are compared with moments determined from the reduced displacement potential method applied to free-field data. Light detection and ranging (lidar) observations, strong ground motions on the free surface in the vicinity of ground zero, and moment tensor inversion results are evidence that the fourth test SPE-4P is a pure explosion, and the moments show goodmore » agreement, 8×10 10 N·m for free-field data versus 9×10 10 N·m for Rg waves. In stark contrast, apparent moments for the first three tests are smaller than near-field moments by factors of 3–4. Relative amplitudes for the three tests determined from Rg interferometry using SPE-4P as an empirical Green’s function indicate that radiation patterns are cylindrically symmetric within a factor of 1.25 (25%). This fact assures that the apparent moments are reliable even though they were measured on just one azimuth. Spallation occurred on the first three tests, and ground-based lidar detected permanent deformations. As such, the source medium suffered late-time damage. In conclusion, destructive interference between Rg waves radiated by explosion and damage sources will reduce amplitudes and explain why apparent moments are smaller than near-field moments based on compressional energy emitted directly from the source.« less

cDNA cloning, functional expression and antifungal activities of a dimeric plant defensin SPE10 from Pachyrrhizus erosus seeds.

PubMed

Song, Xiaomin; Wang, Jing; Wu, Fang; Li, Xu; Teng, Maikun; Gong, Weimin

2005-01-01

SPE10 is an antifungal protein isolated from the seeds of Pachyrrhizus erosus. cDNA encoding a 47 amino acid peptide was cloned by RT-PCR and the gene sequence proved SPE10 to be a new member of plant defensin family. The synthetic cDNA with codons preferred in yeast was cloned into the pPIC9 plasmid directly in-frame with the secretion signal alpha-mating factor, and highly expressed in methylotrophic Pichia pastoris. Activity assays showed the recombinant SPE10 inhibited specifically the growth of several pathogenic fungi as native SPE10. Circular dichroism and fluorescence spectroscopy analysis indicated that the native and recombinant protein should have same folding, though there are eight cystein residues in the sequence. Several evidence suggested SPE10 should be the first dimeric plant defensin reported so far.

Diversity of the citrus HLB bacterium, ‘Candidatus Liberibacter asiaticus’, in psyllids (Diaphorina citri) collected from Murraya paniculata and citrus spp. in Thailand

USDA-ARS?s Scientific Manuscript database

‘Candidatus Liberibacter asiaticus’ (Las) is a phloem inhabiting bacterium that causes huanglongbing disease (HLB), also known as citrus greening associated with three species of a-Proteobacteria in the genus ‘Candidatus Liberibacter sp’. Prophage is an important genetic element of bacterial genomes...

Polarization measurements made on LFRA and OASIS emitter arrays

NASA Astrophysics Data System (ADS)

Geske, Jon; Sparkman, Kevin; Oleson, Jim; Laveigne, Joe; Sieglinger, Breck; Marlow, Steve; Lowry, Heard; Burns, James

2008-04-01

Polarization is increasingly being considered as a method of discrimination in passive sensing applications. In this paper the degree of polarization of the thermal emission from the emitter arrays of two new Santa Barbara Infrared (SBIR) micro-bolometer resistor array scene projectors was characterized at ambient temperature and at 77 K. The emitter arrays characterized were from the Large Format Resistive Array (LFRA) and the Optimized Arrays for Space-Background Infrared Simulation (OASIS) scene projectors. This paper reports the results of this testing.

Apparent Explosion Moments from Rg Waves Recorded on SPE: Implications for the Late-Time Damage Source Model

NASA Astrophysics Data System (ADS)

Patton, H. J.; Larmat, C. S.; Rougier, E.

2016-12-01

Seismic moments for chemical shots making up Phase I of the Source Physics Experiments (SPE) are estimated from 6 Hz Rg waves under the assumption that the shots are pure explosions. These apparent explosion moments are compared to moments determined using the Reduced Displacement Potential (RDP) method applied to free field data. LIDAR/photogrammetry observations, strong ground motions on the free surface near ground zero, and moment tensor inversion results are evidence in support of the fourth shot SPE-4P being essentially a pure explosion. The apparent moment for SPE-4P is 9 × 1010 Nm in good agreement with the RDP moment 8 × 1010 Nm. In stark contrast, apparent moments for the first three shots are three to four times smaller than RDP moments. Data show that spallation occurred on these shots, as well as permanent deformations detected with ground-based LIDAR. As such, the source medium suffered late-time damage. The late-time damage source model predicts destructive interference between Rg waves radiated by explosion and damage sources, which reduces amplitudes and explains why apparent moments are smaller than RDP moments based on compressional energy emitted directly from the source. SPE-5 was conducted at roughly the same yield-scaled burial depth as SPE-2 and -3, but with five times the yield. As such, the damage source model predicts less reduction of apparent moment. At this writing, preliminary results from Rg interferometry and RDP moments confirm this prediction. SPE-6 is scheduled for the fall of 2016, and it should have the strongest damage source of all SPE shots. The damage model predicts that the polarity of Rg waves could be reversed. Realization of this prediction will be strong confirmation of the late-time damage source model. This abstract has a Los Alamos National Laboratory Unlimited Release Number LA-UR-16-25709.

Theoretical performance of hydrogen-bromine rechargeable SPE fuel cell. [Solid Polymer Electrolyte

NASA Technical Reports Server (NTRS)

Savinell, R. F.; Fritts, S. D.

1988-01-01

A mathematical model was formulated to describe the performance of a hydrogen-bromine fuel cell. Porous electrode theory was applied to the carbon felt flow-by electrode and was coupled to theory describing the solid polymer electrolyte (SPE) system. Parametric studies using the numerical solution to this model were performed to determine the effect of kinetic, mass transfer, and design parameters on the performance of the fuel cell. The results indicate that the cell performance is most sensitive to the transport properties of the SPE membrane. The model was also shown to be a useful tool for scale-up studies.

Biological Response to SPE Exposures

NASA Technical Reports Server (NTRS)

Wilson, J. W.; Cucinotta, F. A.; Kim, M.; Shinn, J. L.; Jones, T. D.; Chang, C. K.

2004-01-01

It has long been recognized that a single solar particle event (SPE) can produce, over a short period of time, exposures on the order of LD50 for humans under normal physiological conditions. It is further recognized that recovery from injury over the period of exposure would greatly increase the chances of survival (dose rate effects) although such effects were left unquantified. In the present report we use the bioresponse model derived from a broad range of animal and human exposure data for evaluation of troop readiness in tactical nuclear warfare to evaluate the biological risk posed by the solar event of 4 August 1972. The astronaut blood forming organ (BFO) exposure in deep space would have been 2.2 Sv (1.6 Gy) in a space suit, 1.8 Sv (1.3 Gy) in an aluminum pressure vessel, and 0.7 Sv (0.5 Gy) in an equipment room compared to an X-ray mortality threshold of 1.5 Gy (assuming high dose rate). We find BFO dose rate effectiveness factors for this SPE on the order of 3 to 4, greatly reducing the mortality risks for this event. There is an approximate 3 percent chance that an even larger event may occur for which exposures could be 2-4 times higher. Assured survival of the astronaut requires added shelter shielding and a warning system for this event. The required mass of the shelter shield can be greatly reduced by using hydrogenous materials such as polymers, water, food, and other biological materials in its construction. Limitations of the current bioresponse model arise from the exposures taking place in the microgravity environment wherein the immune system is already challenged and the effective mortality threshold may be reduced by a factor of two. Such microgravity effects could greatly affect astronaut risks.

Determination of Methotrexate, 7-Hydroxymethotrexate, and 2,4-Diamino-N10-methylpteroic Acid by LC-MS/MS in Plasma and Cerebrospinal Fluid and Application in a Pharmacokinetic Analysis of High-Dose Methotrexate

PubMed Central

Roberts, Michael S.; Selvo, Nicholas S.; Roberts, Jessica K.; Daryani, Vinay M.; Owens, Thandranese S.; Harstead, K. Elaine; Gajjar, Amar; Stewart, Clinton F.

2017-01-01

A rapid and robust method for measuring methotrexate (MTX) and its two primary metabolites, 7-hydroxymethotrexate (7-OHMTX) and 2,4-diamino-N10-methylpteroic acid (DAMPA), was developed for use in pharmacokinetic studies of plasma and cerebrospinal fluid samples collected from infants with malignant brain tumors. Sample aliquots (100μL) were prepared for bioanalysis of MTX and metabolites using a Waters Oasis HLB microelution SPE plate. Chromatography was performed using a Phenomenex Synergi Polar-RP 4μ 75 × 2.0mm ID column heated to 40°C. A rapid gradient elution on a Shimadzu HPLC system was used, with mobile phase A consisting of water/formic acid (100/0.1 v/v) and mobile phase B consisting of acetonitrile/formic acid (100/0.1 v/v). Column eluent was analyzed using AB Sciex QTRAP 5500 instrumentation in electrospray ionization mode. The ion transitions (m/z) monitored were 455.2→308.1, 471.1→324.1, and 326.2→175.1 for MTX, 7-OHMTX, and DAMPA respectively. The method was linear over a range of 0.0022 – 5.5 μM for MTX, 0.0085 – 21 μM for 7-OHMTX, and 0.0031 – 7.7 μM for DAMPA. The method was applied to the analysis of serial plasma samples obtained from infants diagnosed with malignant brain tumors receiving high-dose MTX and results were compared to MTX concentrations from a TDx-FLx FPIA. PMID:28824272

Development of a liquid chromatography–tandem mass spectrometry method for the determination of sulfonamides, trimethoprim and dapsone in honey and validation according to Commission Decision 2002/657/EC for banned compounds [corrected].

PubMed

Economou, Anastasios; Petraki, Olympia; Tsipi, Despina; Botitsi, Eleni

2012-08-15

This work reports a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for identification and quantification of seven sulfonamides, trimethoprim and dapsone in honey. The method is based on a solid-phase extraction (SPE) step of the target analytes with Oasis HLB cartridges after acidic hydrolysis of the honey sample to liberate the sugar-bound sulfonamides. Analysis was performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the positive electro-spray ionization (ESI) mode with two different isotopically labeled internal standards with the view to improve the quantitative performance of the method. The method validation has been performed according to the Commission Decision 2002/657/EC; the average recoveries, measured at three concentration levels (1.5, 2.5 and 5.0 μg kg(-1)), have been estimated in the range 70 to 106% while the respective % relative standard deviations of the within-laboratory reproducibility ranged from 6 to 18%. Mean values of the expanded uncertainties calculated were in the range 22-41% at the 99% confidence level. Decision limit (CCα) and detection capability (CCβ) values were in the ranges 0.4-0.9 and 0.7-1.4 μg kg(-1), respectively. Matrix effects have been investigated demonstrating a moderate signal suppression/enhancement for most of the target compounds. The method described has been successfully applied to the analysis of honey samples; sulfamethoxazole, sulfathiazole and trimethoprim were detected in some cases. Copyright © 2012 Elsevier B.V. All rights reserved.

Simultaneous determination of calycosin-7-O-β-D-glucoside, ononin, calycosin, formononetin, astragaloside IV, and astragaloside II in rat plasma after oral administration of Radix Astragali extraction for their pharmacokinetic studies by ultra-pressure liquid chromatography with tandem mass spectrometry.

PubMed

Liu, Xiao-hua; Zhao, Jian-bang; Guo, Long; Yang, Ying-lai; Hu, Fang; Zhu, Rui-juan; Feng, Shi-lan

2014-09-01

A sensitive and reliable ultra-pressure liquid chromatography with tandem mass spectrometry (UPLC-MS) was developed and validated for simultaneous quantification of six main bioactive components, i.e., calycosin-7-O-β-D-glucoside, ononin, calycosin, formononetin, astragaloside IV, and astragaloside II in rat plasma after oral administration of the 95 % ethanol extraction from Radix Astragali. Plasma samples were extracted with Waters Oasis(TM) HLB 1 cc (30 mg) Extraction Cartridges (SPE) separated on an UPLC™ BEH C18 column and detected by MS with electro spray ionization interface in positive selective ion monitoring mode. Calibration curves offered linear ranges of two orders of magnitude with r (2) > 0.99. The method had the lower limit quantification of 1.30, 0.73, 1.17, 2.33, 0.63, and 0.83 ng/mL for ononin, calycosin, calycosin-7-O-β-D-glucoside, formononetin, astragaloside IV, and astragaloside II, respectively, with precision less than 10 %. The RSD of intra- and inter-day variations ranged from 1.66 to 6.46 and 3.39 to 6.58 %. This developed method was applied subsequently to pharmacokinetic studies of the six compounds in rats successfully. The proposed method was for the first time to compare the pharmacokinetic difference between calycosin-7-O-β-D-glucoside and calycosin in rat plasma, so as between ononin and formononetin, and studied to the astragaloside II pharmacokinetics in rat plasma.

cDNA cloning, expression, and mutagenesis of a PR-10 protein SPE-16 from the seeds of Pachyrrhizus erosus.

PubMed

Wu, Fang; Yan, Ming; Li, Yikun; Chang, Shaojie; Song, Xiaomin; Zhou, Zhaocai; Gong, Weimin

2003-12-19

SPE-16 is a new 16kDa protein that has been purified from the seeds of Pachyrrhizus erosus. It's N-terminal amino acid sequence shows significant sequence homology to pathogenesis-related class 10 proteins. cDNA encoding 150 amino acids was cloned by RT-PCR and the gene sequence proved SPE-16 to be a new member of PR-10 family. The cDNA was cloned into pET15b plasmid and expressed in Escherichia coli. The bacterially expressed SPE-16 also demonstrated ribonuclease-like activity in vitro. Site-directed mutation of three conserved amino acids E95A, E147A, Y150A, and a P-loop truncated form were constructed and their different effects on ribonuclease activities were observed. SPE-16 is also able to bind the fluorescent probe 8-anilino-1-naphthalenesulfonate (ANS) in the native state. The ANS anion is a much-utilized "hydrophobic probe" for proteins. This binding activity indicated another biological function of SPE-16.

Interoperability and complementarity of simulation tools for beamline design in the OASYS environment

NASA Astrophysics Data System (ADS)

Rebuffi, Luca; Sanchez del Rio, Manuel

2017-08-01

In the next years most of the major synchrotron radiation facilities around the world will upgrade to 4th-generation Diffraction Limited Storage Rings using multi-bend-achromat technology. Moreover, several Free Electron Lasers are ready-to-go or in phase of completion. These events represent a huge challenge for the optics physicists responsible of designing and calculating optical systems capable to exploit the revolutionary characteristics of the new photon beams. Reliable and robust beamline design is nowadays based on sophisticated computer simulations only possible by lumping together different simulation tools. The OASYS (OrAnge SYnchrotron Suite) suite drives several simulation tools providing new mechanisms of interoperability and communication within the same software environment. OASYS has been successfully used during the conceptual design of many beamline and optical designs for the ESRF and Elettra- Sincrotrone Trieste upgrades. Some examples are presented showing comparisons and benchmarking of simulations against calculated and experimental data.

Electronic tongue response to chemicals in orange juice that change concentration in relation to harvest maturity and citrus greening or Huanglongbing (HLB) disease

USDA-ARS?s Scientific Manuscript database

In an earlier study, the electronic tongue system (etongue) was used to differentiate between orange juice made from healthy fruit and from fruit affected by the citrus greening or Huanglongbing (HLB) disease. This study investigated the reaction of an etongue system to the main chemicals in orange ...

Gravity and magnetic study of the Pahute Mesa and Oasis Valley region, Nye County, Nevada

USGS Publications Warehouse

Mankinen, Edward A.; Hildenbrand, Thomas G.; Dixon, Gary L.; McKee, Edwin H.; Fridrich, Christopher J.; Laczniak, Randell J.

1999-01-01

Regional gravity and aeromagnetic maps reveal the existence of deep basins underlying much of the southwestern Nevada volcanic field, approximately 150 km northwest of Las Vegas. These maps also indicate the presence of prominent features (geophysical lineaments) within and beneath the basin fill. Detailed gravity surveys were conducted in order to characterize the nature of the basin boundaries, delineate additional subsurface features, and evaluate their possible influence on the movement of ground-water. Geophysical modeling of gravity and aeromagnetic data indicates that many of the features may be related to processes of caldera formation. Collapse of the various calderas within the volcanic field resulted in dense basement rocks occurring at greater depths within caldera boundaries. Modeling indicates that collapse occurred along faults that are arcuate and steeply dipping. There are indications that the basement in the western Pahute Mesa - Oasis Valley region consists predominantly of granitic and/or fine-grained siliceous sedimentary rocks that may be less permeable to groundwater flow than the predominantly fractured carbonate rock basement to the east and southeast of the study area. The northeast-trending Thirsty Canyon lineament, expressed on gravity and basin thickness maps, separates dense volcanic rocks on the northwest from less dense intracaldera accumulations in the Silent Canyon and Timber Mountain caldera complexes. The source of the lineament is an approximately 2-km wide ring fracture system with step-like differential displacements, perhaps localized on a pre-existing northeast-trending Basin and Range fault. Due to vertical offsets, the Thirsty Canyon fault zone probably juxtaposes rock types of different permeability and, thus, it may act as a barrier to ground-water flow and deflect flow from Pahute Mesa along its flanks toward Oasis Valley. Within the Thirsty Canyon fault zone, highly fractured rocks may serve also as a conduit

42 CFR 484.11 - Condition of participation: Release of patient identifiable OASIS information.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Condition of participation: Release of patient... Administration § 484.11 Condition of participation: Release of patient identifiable OASIS information. The HHA and agent acting on behalf of the HHA in accordance with a written contract must ensure the...

OASIS: Ocean-Atmosphere-Sea-Ice-Snowpack Interactions in Polar Regions

NASA Astrophysics Data System (ADS)

Bottenheim, J. W.; Abbatt, J.; Beine, H.; Berg, T.; Bigg, K.; Domine, F.; Leck, C.; Lindberg, S.; Matrai, P.; MacDonald, R.; McConnell, J.; Platt, U.; Raspopov, O.; Shepson, P.; Shumilov, O.; Stutz, J.; Wolff, E.

2004-05-01

While Polar regions encompass a large part of the globe, little attention has been paid to the interactions between the atmosphere and its extensive snow-covered surfaces. Recent discoveries in the Arctic and Antarctic show that the top ten centimeters of snow is not simply a white blanket but in fact is a surprisingly reactive medium for chemical reactions in the troposphere. It has been concluded that interlinked physical, chemical, and biological mechanisms, fueled by the sun and occurring in the snow, are responsible for depletion of tropospheric ozone and gaseous mercury. At the same time production of highly reactive compounds (e.g. formaldehyde, nitrogen dioxide) has been observed at the snow surface. Air-snow interactions also have an impact on the chemical composition of the snow and hence the nature and amounts of material released in terrestrial/marine ecosystems during the melting of seasonal snow-packs. Many details of these possibly naturally occurring processes are yet to be discovered. For decades humans have added waste products including acidic particles (sulphates) and toxic contaminants such as gaseous mercury and POPs (persistent organic pollutants) to the otherwise pristine snow surface. Virtually nothing is known about transformations of these contaminants in the snowpack, making it impossible to assess the risk to the polar environment, including humans. This is especially disconcerting when considering that climate change will undoubtedly alter the nature of these transformations involving snow, ice, atmosphere, ocean, and, ultimately, biota. To address these topics an interdisciplinary group of scientists from North America, Europe and Japan is developing a set of coordinated research activities under the banner of the IGBP programs IGAC and SOLAS. The program of Ocean-Atmosphere-Sea Ice-Snowpack (OASIS) interactions has been established with a mission statement aimed at determining the impact of OASIS chemical exchange on tropospheric

An Overview of the Source Physics Experiments (SPE) at the Nevada National Security Site (NNSS)

NASA Astrophysics Data System (ADS)

Snelson, C. M.; Barker, D. L.; White, R. L.; Emmitt, R. F.; Townsend, M. J.; Graves, T. E.; Becker, S. A.; Teel, M. G.; Lee, P.; Antoun, T. H.; Rodgers, A.; Walter, W. R.; Mellors, R. J.; Brunish, W. M.; Bradley, C. R.; Patton, H. J.; Hawkins, W. L.; Corbell, B. H.; Abbott, R. E.; SPE Working Group

2011-12-01

Modeling of explosion phenomenology has been primarily empirically based when looking at the seismic, infrasound, and acoustic signals. In order to detect low-yield nuclear explosions under the Comprehensive Nuclear Test-Ban Treaty (CTBT), we must be able to understand and model the explosive source in settings beyond where we have empirical data. The Source Physics Experiments (SPE) at the Nevada National Security Site are the first step in this endeavor to link the empirically based with the physics-based modeling to develop this predictive capability. The current series of tests is being conducted in a granite body called the Climax Stock. This location was chosen for several reasons, including the site's expected "simple geology"-the granite is a fairly homogeneous body. In addition, data are available from underground nuclear tests that were conducted in the same rock body, and the nature of the geology has been well-documented. Among the project goals for the SPE is to provide fully coupled seismic energy to the seismic and acoustic seismic arrays so that the transition between the near and far-field data can be modeled and our scientists can begin to understand how non-linear effects and anisotropy control seismic energy transmission and partitioning. The first shot for the SPE was conducted in May 2011 as a calibration shot (SPE1) with 220 lb (100 kg) of chemical explosives set at a depth of 180 ft (55 m). An array of sensors and diagnostics recorded the shot data, including accelerometers, geophones, rotational sensors, short-period and broadband seismic sensors, Continuous Reflectometry for Radius vs. Time Experiment (CORRTEX), Time of Arrival (TOA), Velocity of Detonation (VOD) as well as infrasound sensors. The three-component accelerometer packages were set at depths of 180 ft (55 m), 150 ft (46 m), and 50 ft (15 m) in two rings around ground zero (GZ); the inner ring was at 10 m and the outer ring was 20 m from GZ. Six sets of surface accelerometers

SPE analysis of high efficiency PMTs for the DEAP-3600 dark matter detector

NASA Astrophysics Data System (ADS)

Olsen, Kevin; Hallin, Aksel; DEAP/CLEAN Collaboration

2011-09-01

The Dark matter Experiment using Argon Pulse-shape discrimination is a collaborative effort to develop a next-generation, tonne-scale dark matter detector at SNOLAB. The detector will feature a single-phase liquid argon (LAr) target surrounded by an array of 266 photomultiplier tubes (PMTs). A new high-efficiency Hamamatsu R877-100 PMT has been delivered to the University of Alberta for evaluation by the DEAP collaboration. The increase in efficiency could lead to a much greater light yield, but other experiments have reported a slower rise time [1],[2]. We have placed the PMT in a small dark box and had a base and preamplifier designed to be used with either an oscilloscope or a multi-channel analyzer. With this setup we have demonstrated the PMT's ability to distinguish single photo-electrons (SPE) and characterized the PMT by measuring the SPE pulse height spectrum, the peak-to-valley ratio, the dark pulse rate, the baseline, time resolution and SPE efficiency for varying the high voltage supplied to the PMT.

Spectral reflectance properties of major objects in desert oasis: a case study of the Weigan-Kuqa river delta oasis in Xinjiang, China.

PubMed

Zhang, Fei; Tiyip, Tashpolat; Ding, Jianli; Sawut, Mamat; Tashpolat, Nigara; Kung, Hsiangte; Han, Guihong; Gui, Dongwei

2012-08-01

Aiming at the remote sensing application has been increasingly relying on ground object spectral characteristics. In order to further research the spectral reflectance characteristics in arid area, this study was performed in the typical delta oasis of Weigan and Kuqa rivers located north of Tarim Basin. Data were collected from geo-targets at multiple sites in various field conditions. The spectra data were collected for different soil types including saline-alkaline soil, silt sandy soil, cotton field, and others; vegetations of Alhagi sparsifolia, Phragmites australis, Tamarix, Halostachys caspica, etc., and water bodies. Next, the data were processed to remove high-frequency noise, and the spectral curves were smoothed with the moving average method. The derivative spectrum was generated after eliminating environmental background noise so that to distinguish the original overlap spectra. After continuum removal of the undesirable absorbance, the spectrum curves were able to highlight features for both optical absorbance and reflectance. The spectrum information of each ground object is essential for fully utilizing the multispectrum data generated by remote sensing, which will need a representative spectral library. In this study using ENVI 4.5 software, a preliminary spectral library of surface features was constructed using the data surveyed in the study area. This library can support remote sensing activities such as feature investigation, vegetation classification, and environmental monitoring in the delta oasis region. Future plan will focus on sharing and standardizing the criteria of professional spectral library and to expand and promote the utilization of the spectral databases.

SPE-GC/FTD determination of N-methyl-2-pyrrolidone and its metabolites in urine.

PubMed

Kubota, Ryuichi; Endo, Yoko; Takeuchi, Akito; Inoue, Yoshinori; Ogata, Hiroko; Ogawa, Masanori; Nakagawa, Tomoo; Onda, Nobuhiko; Endo, Ginji

2007-07-01

An analytical method using a combination of solid-phase extraction (SPE) and gas chromatography with a flame thermionic detector (GC/FTD) was developed for determination of N-methyl-2-pyrrolidone (NMP), N-methylsuccinimide (MSI), and 2-hydroxy-N-methylsuccinimide (2-HMSI) in human urine. The SPE cartridge of poly(divinylbenzene/hydroxymethacrylate) used was directly loaded with urine sample, followed by elution with methyl isobutyl ketone (MIBK) and subsequent centrifugation, and the supernatant was injected into the capillary GC using a DB1701. This method allowed efficient separation of NMP, MSI, and 2-HMSI, which were nearly free of interference by other GC peaks arising from urine. Recoveries of NMP, MSI, and 2-HMSI from the SPE cartridge were about 98, 101, and 67%, respectively, with limits of detection of 0.04, 0.02, and 0.06 mg/L, respectively, which met the regulatory requirements. The present method was used for assay in biological monitoring of workers exposed to NMP in their occupational environment.

Sequence stratigraphy of the Maastrichtian-Paleocene succession at the Dakhla Oasis, Western Desert, Egypt

NASA Astrophysics Data System (ADS)

Hewaidy, Abdel Galil A.; Farouk, Sherif; Bazeen, Youssef S.

2017-12-01

The Maastrichtian-Paleocene succession at the Dakhla Oasis is marked by the presence of a typical Nile Valley Facies represented by the Dakhla and Tarawan formations in Edmonstone and Qur El Malik sections in the central and western parts of the oasis, while a mixed Nile Valley and Garra Al-Arbain facies represented by Dakhla, Kurkur and Tarawan formations in Teneida section in the eastern part of the oasis adjacent to the Abu Tartur Plateau. These sections were examined for their foraminiferal contents, lithologic characters and stratigraphic boundaries. The distribution of foraminifera in the studied sections is variable and inconstant, as the planktonics are concentrated only at certain levels, which may be considered as a time intervals of transgression and maximum flooding surfaces. Eight planktonic biozones are distinguished in this work; of theses two are of Maastrichtain age and six are of Paleocene age. Eight 3rd order depositional sequences are recognized in the studied Maastrichtian-Paleocene succession based on the time stratigraphic boundaries released from the planktonic foraminifera and sea level changes which are released from the paleoecologic interpretations. The distinguished sequences are subdivided into their systems tracts based on the paleobathymetric interpretations of P/B% and benthic biofacies analysis. These sequences are bounded by eight sequence boundaries (SB A - SB H) represented by unconformity surfaces and depositional hiatuses. The correlation of the sequence boundaries of the established depositional sequences with the eustatic sea level curve, suggesting that these depositional sequences were resulted from the interplay of eustatic sea-level changes and local tectonic activities.

Sensitivity of the reference evapotranspiration to key climatic variables during the growing season in the Ejina oasis northwest China.

PubMed

Hou, Lan-Gong; Zou, Song-Bing; Xiao, Hong-Lang; Yang, Yong-Gang

2013-01-01

The standardized FAO56 Penman-Monteith model, which has been the most reasonable method in both humid and arid climatic conditions, provides reference evapotranspiration (ETo) estimates for planning and efficient use of agricultural water resources. And sensitivity analysis is important in understanding the relative importance of climatic variables to the variation of reference evapotranspiration. In this study, a non-dimensional relative sensitivity coefficient was employed to predict responses of ETo to perturbations of four climatic variables in the Ejina oasis northwest China. A 20-year historical dataset of daily air temperature, wind speed, relative humidity and daily sunshine duration in the Ejina oasis was used in the analysis. Results have shown that daily sensitivity coefficients exhibited large fluctuations during the growing season, and shortwave radiation was the most sensitive variable in general for the Ejina oasis, followed by air temperature, wind speed and relative humidity. According to this study, the response of ETo can be preferably predicted under perturbation of air temperature, wind speed, relative humidity and shortwave radiation by their sensitivity coefficients.

Lessons Learned from Near Field Modeling and Data Collected at the SPE Chemical Explosions in Jointed Rock Masses

NASA Astrophysics Data System (ADS)

Vorobiev, O.; Ezzedine, S. M.; Hurley, R.; Antoun, T.; Glenn, L.

2016-12-01

This work describes the near-field modeling of wave propagation from underground chemicalexplosions conducted at the Nevada National Security Site (NNSS) in fractured granitic rock. Lab testsperformed on granite samples excavated from various locations at the SPE site have shown littlevariability in mechanical properties. Granite at this scale can be considered as an isotropic medium. Wehave shown, however, that on the scale of the pressure waves generated during chemical explosions(tens of meters), the effective mechanical properties may vary significantly and exhibit both elastic andplastic anisotropies due to local variations in joint properties such as spacing orientation, joint aperture,cohesion and saturation. Since including every joint in a discrete fashion in computational model is notfeasible, especially for large-scale calculations ( 1.5 km domain), we have developed a computationaltechnique to upscale mechanical properties for various scales (frequencies) using geophysicalcharacterization conducted during recent SPE tests at the NNSS. Stochastic representation of thesefeatures based on the field characterizations has been implemented into LLNL's Geodyn-L hydrocode.Scale dependency in mechanical properties is important in order to understand how the ground motionscales with yield. We hope that such an approach will not only provide a better prediction of theground motion observed in the SPE (where the yield varies from 100 kg to few tons of TNT equivalent)but also will allow us to extrapolate results of the SPE to sources with bigger yields. We have validatedour computational results by comparing the measured and computed ground motion at various rangesfor experiments of various yields (SPE1-SPE5). Using the new model we performed severalcomputational studies to identify the most important mechanical properties of the rock mass specific tothe SPE site and to understand their roles in the observed ground motion in the near-field. We willpresent a series

Analysis Study of Stevioside and Rebaudioside A from Stevia rebaudiana Bertoni by Normal Phase SPE and RP-HPLC

NASA Astrophysics Data System (ADS)

Martono, Y.; Rohman, A.; Riyanto, S.; Martono, S.

2018-04-01

Solid Phase Extraction (SPE) method using silica as sorbent for stevioside and rebaudiosida A analysis in Stevia rebaudiana Bertoni leaf have not been performed. The aim of this study is to develop SPE method using silica as sorbent for Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) analysis of stevioside and rebaudiosida A in S. rebaudiana leaf. The results of this study indicate that the optimal conditions for normal phase SPE (silica) are conditioned with 3.0 mL of hexane. The sample loading volume is 0.1 mL. Cartridge is eluted with 1.0 mL acetonitrile: water (80: 20, v/v) to separate both analytes. The cartridge is washed with chloroform and water of 0.3 mL respectively. The developed SPE sample preparation method meets the accuracy and precision test and can be used for the analysis of stevioside and rebaudioside A by RP-HPLC.

Analysis of the Source Physics Experiment SPE4 Prime Using State-Of Parallel Numerical Tools.

NASA Astrophysics Data System (ADS)

Vorobiev, O.; Ezzedine, S. M.; Antoun, T.; Glenn, L.

2015-12-01

This work describes a methodology used for large scale modeling of wave propagation from underground chemical explosions conducted at the Nevada National Security Site (NNSS) fractured granitic rock. We show that the discrete natures of rock masses as well as the spatial variability of the fabric of rock properties are very important to understand ground motions induced by underground explosions. In order to build a credible conceptual model of the subsurface we integrated the geological, geomechanical and geophysical characterizations conducted during recent test at the NNSS as well as historical data from the characterization during the underground nuclear test conducted at the NNSS. Because detailed site characterization is limited, expensive and, in some instances, impossible we have numerically investigated the effects of the characterization gaps on the overall response of the system. We performed several computational studies to identify the key important geologic features specific to fractured media mainly the joints characterized at the NNSS. We have also explored common key features to both geological environments such as saturation and topography and assess which characteristics affect the most the ground motion in the near-field and in the far-field. Stochastic representation of these features based on the field characterizations has been implemented into LLNL's Geodyn-L hydrocode. Simulations were used to guide site characterization efforts in order to provide the essential data to the modeling community. We validate our computational results by comparing the measured and computed ground motion at various ranges for the recently executed SPE4 prime experiment. We have also conducted a comparative study between SPE4 prime and previous experiments SPE1 and SPE3 to assess similarities and differences and draw conclusions on designing SPE5.

Hindlimb suspension and SPE-like radiation impairs clearance of bacterial infections.

PubMed

Li, Minghong; Holmes, Veronica; Zhou, Yu; Ni, Houping; Sanzari, Jenine K; Kennedy, Ann R; Weissman, Drew

2014-01-01

A major risk of extended space travel is the combined effects of weightlessness and radiation exposure on the immune system. In this study, we used the hindlimb suspension model of microgravity that includes the other space stressors, situational and confinement stress and alterations in food intake, and solar particle event (SPE)-like radiation to measure the combined effects on the ability to control bacterial infections. A massive increase in morbidity and decrease in the ability to control bacterial growth was observed using 2 different types of bacteria delivered by systemic and pulmonary routes in 3 different strains of mice. These data suggest that an astronaut exposed to a strong SPE during extended space travel is at increased risk for the development of infections that could potentially be severe and interfere with mission success and astronaut health.

Hindlimb Suspension and SPE-Like Radiation Impairs Clearance of Bacterial Infections

PubMed Central

Li, Minghong; Holmes, Veronica; Zhou, Yu; Ni, Houping; Sanzari, Jenine K.; Kennedy, Ann R.; Weissman, Drew

2014-01-01

A major risk of extended space travel is the combined effects of weightlessness and radiation exposure on the immune system. In this study, we used the hindlimb suspension model of microgravity that includes the other space stressors, situational and confinement stress and alterations in food intake, and solar particle event (SPE)-like radiation to measure the combined effects on the ability to control bacterial infections. A massive increase in morbidity and decrease in the ability to control bacterial growth was observed using 2 different types of bacteria delivered by systemic and pulmonary routes in 3 different strains of mice. These data suggest that an astronaut exposed to a strong SPE during extended space travel is at increased risk for the development of infections that could potentially be severe and interfere with mission success and astronaut health. PMID:24454913

OASIS Observation and Analysis of Smectic Islands in Space

NASA Technical Reports Server (NTRS)

Tin, Padetha

2014-01-01

The Observation and Analysis of Smectic Islands in Space (OASIS) project comprises a series of experiments that will probe the interfacial and hydrodynamic behavior of freely suspended liquid crystal films in space. These are the thinnest known stable condensed phase structures, making them ideal for studies of fluctuation and interface phenomena. The experiments seek to verify theories of coarsening dynamics, hydrodynamic flow, relaxation of hydrodynamic perturbations, and hydrodynamic interactions of a near two-dimensional structure. The effects of introducing islands or droplets on a very thin bubble will be studied, both as controllable inclusions that modify the flow and as markers of flow.

GCR and SPE Radiation Effects in Materials

NASA Technical Reports Server (NTRS)

Waller, Jess; Rojdev, Kristina; Nichols, Charles

2016-01-01

This Year 3 project provides risk reduction data to assess galactic cosmic ray (GCR) and solar particle event (SPE) space radiation damage in materials used in manned low-earth orbit, lunar, interplanetary, and Martian surface missions. Long duration (up to 50 years) space radiation damage is being quantified for materials used in inflatable structures (1st priority), and space suit and habitable composite materials (2nd priority). The data collected has relevance for nonmetallic materials (polymers and composites) used in NASA missions where long duration reliability is needed in continuous or intermittent space radiation fluxes.

Data Release Report for Source Physics Experiments 2 and 3 (SPE-2 and SPE-3) Nevada National Security Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Townsend, Margaret; Obi, Curtis

2015-01-26

The second Source Physics Experiment shot (SPE-2) was conducted in Nevada on October 25, 2011, at 1900:00.011623 Greenwich Mean Time (GMT). The explosive source was 997 kilograms (kg) trinitrotoluene (TNT) equivalent of sensitized heavy ammonium fuel oil (SHANFO) detonated at a depth of 45.7 meters (m). The third Source Physics Experiment shot (SPE-3) was conducted in Nevada on July 24, 2012, at 1800:00.44835 GMT. The explosive source was 905 kg TNT equivalent of SHANFO detonated at a depth of 45.8 m. Both shots were recorded by an extensive set of instrumentation that includes sensors both at near-field (less than 100more » m) and far-field (100 m or greater) distances. The near-field instruments consisted of three-component accelerometers deployed in boreholes at 15, 46, and 55 m depths around the shot and a set of single-component vertical accelerometers on the surface. The far-field network was composed of a variety of seismic and acoustic sensors, including short-period geophones, broadband seismometers, three-component accelerometers, and rotational seismometers at distances of 100 m to 25 kilometers. This report coincides with the release of these data for analysts and organizations that are not participants in this program. This report describes the second and third Source Physics Experiment shots and the various types of near-field and far-field data that are available.« less

Psychometrics of a Brief Measure of Anxiety to Detect Severity and Impairment: The Overall Anxiety Severity and Impairment Scale (OASIS)

PubMed Central

Norman, Sonya B.; Campbell-Sills, Laura; Hitchcock, Carla A.; Sullivan, Sarah; Rochlin, Alexis; Wilkins, Kendall C.; Stein, Murray B.

2010-01-01

Brief measures of anxiety related severity and impairment that can be used across anxiety disorders and with subsyndromal anxiety are lacking. The Overall Anxiety Severity and Impairment Scale (OASIS) have shown strong psychometric properties with college students and primary care patients. This study examines sensitivity, specificity, and efficiency of an abbreviated version of the OASIS that takes only 2–3 minutes to complete using a non-clinical (college student) sample. 48 participants completed the OASIS and SCID for anxiety disorders, 21 had a diagnosis of ≥1 anxiety disorder, and 4 additional participants had a subthreshold diagnosis. A cut-score of 8 best discriminated those with anxiety disorders from those without, successfully classifying 78% of the sample with 69% sensitivity and 74% specificity. Results from a larger sample (n=171) showed a single factor structure and excellent convergent and divergent validity. The availability of cut-scores for a non-clinical sample furthers the utility of this measure for settings where screening or brief assessment of anxiety is needed. PMID:20609450

42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

...— (1) Instruct each HHA on the administration of the data set, privacy/confidentiality of the data set, and integration of the OASIS data set into the facility's own record keeping system; (2) Instruct each... and data base requirements. 488.68 Section 488.68 Public Health CENTERS FOR MEDICARE & MEDICAID...

42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

...— (1) Instruct each HHA on the administration of the data set, privacy/confidentiality of the data set, and integration of the OASIS data set into the facility's own record keeping system; (2) Instruct each... and data base requirements. 488.68 Section 488.68 Public Health CENTERS FOR MEDICARE & MEDICAID...

42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

...— (1) Instruct each HHA on the administration of the data set, privacy/confidentiality of the data set, and integration of the OASIS data set into the facility's own record keeping system; (2) Instruct each... and data base requirements. 488.68 Section 488.68 Public Health CENTERS FOR MEDICARE & MEDICAID...

42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

...— (1) Instruct each HHA on the administration of the data set, privacy/confidentiality of the data set, and integration of the OASIS data set into the facility's own record keeping system; (2) Instruct each... and data base requirements. 488.68 Section 488.68 Public Health CENTERS FOR MEDICARE & MEDICAID...

Trypanosoma mega (Kinetoplastida) from Bufo viridis in Siwah Oasis, Egypt.

PubMed

Ashour, A A; Gaafar, N A

1997-04-01

A large pleomorphic trypanosome, identified as Trypanosoma mega, is described from the toad Bufo viridis collected from Siwah Oasis at the Western Desert of Egypt. The prevalence of the trypanosome is 83.3%. Three trypanosome forms are described, small, intermediate and large stumpy form. Observations were also made on the lysed (diffused) trypanosomes. This is the first record of T. mega from B. viridis in Egypt which represents a new host and new geographical location. The measurements of the present trypanosome are given and compared with related forms previously described from Egypt.

Genetic and Molecular Characterization of the Caenorhabditis Elegans Spermatogenesis-Defective Gene Spe-17

PubMed Central

L'Hernault, S. W.; Benian, G. M.; Emmons, R. B.

1993-01-01

Two self-sterile mutations that define the spermatogenesis-defective gene spe-17 have been analyzed. These mutations affect unc-22 and fail to complement each other for both Unc-22 and spermatogenesis defects. Both of these mutations are deficiencies (hcDf1 and hDf13) that affect more than one transcription unit. Genomic DNA adjacent to and including the region deleted by the smaller deficiency (hcDf1) has been sequenced and four mRNAs (including unc-22) have been localized to this sequenced region. The three non unc-22 mRNAs are shown to be sex-specific: a 1.2-kb mRNA that can be detected in sperm-free hermaphrodites and 1.2- and 0.56-kb mRNAs found in males. hDf13 deletes at least 55 kb of chromosome IV, including all of unc-22, both male-specific mRNAs and at least part of the female-specific mRNA. hcDf1, which is approximately 15.6 kb, deletes only the 5' end of unc-22 and the gene that encodes the 0.56-kb male-specific mRNA. The common defect that apparently accounts for the defective sperm in hcDf1 and hDf13 homozygotes is deletion of the spe-17 gene, which encodes the 0.56-kb mRNA. Strains carrying two copies of either deletion are self-fertile when they are transgenic for any of four extrachromosomal array that include spe-17. We have sequenced two spe-17 cDNAs, and the deduced 142 amino acid protein sequence is highly charged and rich in serine and threonine, but shows no significant homology to any previously determined protein sequence. PMID:8349108

Recruiting and Retaining High-Quality Teachers. SPeNSE Summary Sheet.

ERIC Educational Resources Information Center

Westat, Inc., Rockville, MD.

This report summarizes the data from the Study of Special Needs in Special Education (SPeNSE), a national study of personnel in special education. It focuses on data related to recruiting and retaining high-quality special education teachers. Findings indicate: (1) in 1999-2000, more than 12,000 openings for special education teachers were left…

[Spatial differentiation and impact factors of Yutian Oasis's soil surface salt based on GWR model].

PubMed

Yuan, Yu Yun; Wahap, Halik; Guan, Jing Yun; Lu, Long Hui; Zhang, Qin Qin

2016-10-01

In this paper, topsoil salinity data gathered from 24 sampling sites in the Yutian Oasis were used, nine different kinds of environmental variables closely related to soil salinity were selec-ted as influencing factors, then, the spatial distribution characteristics of topsoil salinity and spatial heterogeneity of influencing factors were analyzed by combining the spatial autocorrelation with traditional regression analysis and geographically weighted regression model. Results showed that the topsoil salinity in Yutian Oasis was not of random distribution but had strong spatial dependence, and the spatial autocorrelation index for topsoil salinity was 0.479. Groundwater salinity, groundwater depth, elevation and temperature were the main factors influencing topsoil salt accumulation in arid land oases and they were spatially heterogeneous. The nine selected environmental variables except soil pH had significant influences on topsoil salinity with spatial disparity. GWR model was superior to the OLS model on interpretation and estimation of spatial non-stationary data, also had a remarkable advantage in visualization of modeling parameters.

DOE/NV/25946--1586 Geologic Assessment of the Damage Zone from the Second Test at Source Physics Experiment-Nevada (SPE-N)

NASA Astrophysics Data System (ADS)

Townsend, M.; Huckins-Gang, H.; Prothro, L.; Reed, D.

2012-12-01

The National Center for Nuclear Security, established by the U.S. Department of Energy, National Nuclear Security Administration, is conducting a series of explosive tests at the Nevada National Security Site that are designed to increase the understanding of certain basic physical phenomena associated with underground explosions. These tests will aid in developing technologies that might be used to detect underground nuclear explosions in support of verification activities for the Comprehensive Nuclear-Test-Ban Treaty. The initial project is a series of explosive tests, known collectively as the Source Physics Experiment-Nevada (SPE-N), being conducted in granitic rocks. The SPE N test series is designed to study the generation and propagation of seismic waves. The results will help advance the seismic monitoring capability of the United States by improving the predictive capability of physics-based modeling of explosive phenomena. The first SPE N (SPE N1) test was conducted in May 2011, using 0.1 ton of explosives at the depth of 54.9 m in the U 15n source hole. SPE N2 was conducted in October 2011, using 1.0 ton of explosives at the depth of 45.7 m in the same source hole. The SPE N3 test was conducted in the same source hole in July 2012, using the same amount and type of explosive as for SPE N2, and at the same depth as SPE N2, within the damage zone created by the SPE N2 explosion to investigate damage effects on seismic wave propagation. Following the SPE N2 shot and prior to the SPE N3 shot, the core hole U-15n#10 was drilled at an angle from the surface to intercept the SPE N2 shot point location to obtain information necessary to characterize the damage zone. The desire was to determine the position of the damage zone near the shot point, at least on the northeast, where the core hole penetrated it, and obtain information on the properties of the damaged medium. Geologic characterization of the post-SPE N2 core hole included geophysical logging, a

Analysis of Human Disturbance and Ecological Security Evolution in Oasis in Arid Area Based on LUCC: A Case Study of Oasis in the Northern Tianshan Mountain Slope Economic Zone

NASA Astrophysics Data System (ADS)

Song, W. J.; Chen, M. H.; Zhang, Q.; Liu, S. S.; Yang, J. N.

2017-07-01

Oases in arid areas are environmentally and economically vulnerable regions. Study on ecological security of oases in arid areas is of great significance to the stability and the economic development of oases. Based on Land Use/Land Cover data in 1965, 1980, 1995, 2005 and 2015, the study analyze the temporal and spatial changes in human disturbance and ecological security of oases in the Northern Tianshan Mountain Slope Economic Zone (NTMSEZ) in recent 50 years by establishing the ecological security index (ESI) through human disturbance index and landscape vulnerability index. The results showed that: in recent 50 years, the human disturbance of the NTMSEZ has been increased to current moderate human impacts. Urban construction, oasis expansion and farmland reclamation are the main factors of the increment. The human disturbance in Urumchi, Shihezi, Kuitun, Miquan and Changji is higher than that in other oases and that in core areas of oasis is higher than other areas. The ESI of the NTMSEZ increases firstly and then decreases. In most areas, the ESI is “relatively unsafe” and “critical”. However, there are increasingly more vulnerable areas, moving northwestwards and expanding southwards. The ESI gradually presents a “NW-SE” trend of zonal distribution pattern.

Oceanic Area System Improvement Study (OASIS). Volume IV. Caribbean Region Air Traffic Services System Description.

DTIC Science & Technology

1981-09-01

OASIS) U Final Report This report i.s one of a set of companion documents which includes the following volumes: Volume I Executive Summary and...Northern Coastal Region of 4 the Directorate of Engineering and Systems (Direccion de Ingenieria y Sistemas ), which is responsible for maintenance of the

Imaging an Explosion with a 1000 Sensors: The SPE Large N Array

NASA Astrophysics Data System (ADS)

Mellors, R. J.; Snelson, C. M.; Pitarka, A.; Chen, T.; Matzel, E.; Walter, W. R.

2016-12-01

The Source Physics Experiment (SPE) is a series of heavily instrumented chemical explosions at the Nevada National Security Site (NNSS) designed to improve understanding of seismic wave generation and propagation from explosions. On April 26, 2016, a 5000 kg TNT equivalent chemical explosion (SPE5) was detonated at a depth of 76.5 meters (center) in a stemmed hole. The explosion was recorded by a temporary deployment of 1000 geophones with a variable spacing from 25 to 100 m and consisting of 500 vertical and 500 three-component 5 Hz geophones. Distance from ground zero to the geophones range from 400 to 3000 m. The shot is located in a weathered granite intrusive body surrounded by volcanic tuffs, Paleozoic carbonates, and alluvium. The purpose is to map the 3D waveform propagation with emphasis on the generation of S waves and to compare with synthetics. A focus is the transition from the granite to alluvium that occurs at a steeply dipping strike-slip fault. A secondary goal is to record ambient noise data for tomography. An active source experiment using a weight drop was also conducted. Data recovery was good, with approximately 95% of data recovered from the shot and up to 99% in the following weeks. In addition to the SPE5 shot, a variety of local earthquakes and teleseismic events were recorded. Prepared by LLNL under Contract DE-AC52-07NA27344.

Psychometrics of the Overall Anxiety Severity and Impairment Scale (OASIS) in a sample of women with and without trauma histories.

PubMed

Norman, Sonya B; Allard, Carolyn B; Trim, Ryan S; Thorp, Steven R; Behrooznia, Michelle; Masino, Tonya T; Stein, Murray B

2013-04-01

Many women have unidentified anxiety or trauma histories that can impact their health and medical treatment-seeking behavior. This study examined the sensitivity, specificity, efficiency, and sensitivity to change of the Overall Anxiety Severity and Impairment Scale (OASIS) for identifying an anxiety disorder in a female sample with and without trauma history related to intimate partner violence (IPV). Forty-three women with full or partial PTSD from IPV and 41 women without PTSD completed the OASIS. All participants with trauma history completed the Clinician Administered PTSD Scale. This report is a secondary analysis of a study on the neurobiology of psychological trauma in survivors of IPV recruited from the community. A cut-score of 5 best discriminated those with PTSD from those without, successfully classifying 91% of the sample with 93% sensitivity and 90% specificity. The measure showed strong sensitivity to change in a subsample of 20 participants who completed PTSD treatment and strong convergent and divergent validity in the full sample. This study suggests that the OASIS can identify the presence of an anxiety disorder among a female sample of IPV survivors when PTSD is present.

Trace analysis of endocrine disrupting compounds in environmental water samples by use of solid-phase extraction and gas chromatography with mass spectrometry detection.

PubMed

Azzouz, Abdelmonaim; Ballesteros, Evaristo

2014-09-19

A novel analytical method using a continuous solid-phase extraction system in combination with gas chromatography-mass spectrometry for the simultaneous separation and determination of endocrine disrupting compounds (EDCs) is reported. The method was applied to major EDCs of various types including parabens, alkylphenols, phenylphenols, bisphenol A and triclosan in water. Samples were preconcentrated by using an automatic solid-phase extraction module containing a sorbent column, and retained analytes eluted with acetonitrile for derivatization with a mixture of N,O-bis(trimethylsilyl)trifluoroacetamide and trimethylchlorosilane. A number of variables potentially influencing recovery of the target compounds such as the type of SPE sorbent (Silica gel, Florisil, RP-C18, Amberlite XAD-2 and XAD-4, Oasis HLB and LiChrolut EN), eluent and properties of the water including pH and ionic strength, were examined. LiChrolut EN was found to be the most efficient sorbent for retaining the analytes, with ∼100% efficiency. The ensuing method was validated with good analytical results including low limits of detection (0.01-0.08ng/L for 100mL of sample) and good linearity (r(2)>0.997) throughout the studied concentration ranges. The method exhibited good accuracy (recoveries of 90-101%) and precision (relative standard deviations less than 7%) in the determination of EDCs in drinking, river, pond, well, swimming pool and waste water. Waste water samples were found to contain the largest number and highest concentrations of analytes (3.2-390ng/L). Copyright © 2014 Elsevier B.V. All rights reserved.

A sensitive method for the determination of Sulfonamides in seawater samples by Solid Phase Extraction and UV-Visible spectrophotometry

NASA Astrophysics Data System (ADS)

Errayess, Sophia Ait; Lahcen, Abdellatif Ait; Idrissi, Laila; Marcoaldi, Caterina; Chiavarini, Salvatore; Amine, Aziz

2017-06-01

The authors have developed a sensitive spectrophotometric method for determination of sulfonamide derivatives such as sulfanilamide (SAA), sulfadiazine (SDZ), sulfacetamide (SCT) sulfamethoxazole (SMX), sulfamerazine (SMR), sulfadimethoxine (SDX), sulfamethiazole (SMT) and Sulfathiazole (STZ). This method is based on the Bratton-Marshall reaction, which involves the diazotization of sulfonamides with sodium nitrite under acidic conditions, followed by coupling with N-(1-naphtyl) ethylenediamine dihydrochloride (NED) to form a pink colored compound. Therefore, the Bratton-Marshall method was modified by optimizing the reaction conditions, which allows us to determine a low concentration range of sulfonamides compared to the reported methods. The limits of detection and quantification obtained were 0.019-0.05 and 0.06-0.16 μg mL- 1, respectively. In comparison with other reported methods using different coupling agents, the proposed method was found to be the most simple and sensitive for sulfonamides determination. In this paper, the modified method was successfully employed for the determination of sulfonamides in drinking water, seawater and pharmaceutical and veterinary formulations. The purpose of this work is to optimize and develop a simple method for extraction and concentration of sulfonamides present as residues in seawater and their quantification with the recommended spectrophotometric method. Solid phase extraction (SPE) of sulfonamides from seawater samples was evaluated using Oasis HLB cartridges (3 mL, 540 mg). The recovery efficiency was investigated in the sulfonamides concentration range comprised between 0.19 and 126 ng mL- 1. The ease of use of this extraction method makes it very useful for routine laboratory work.

A High-Quality Teacher for Every Classroom. SPeNSE Summary Sheet.

ERIC Educational Resources Information Center

Westat, Inc., Rockville, MD.

This report from the Study of Personnel Needs in Special Education (SPeNSE) focuses on working conditions that affect special education teachers and how teachers acquire needed professional skills. The report found: (1) 80% of special education teachers serve students with two or more primary disabilities; (2) almost one-fourth of students served…

The speEspeD operon of Escherichia coli. Formation and processing of a proenzyme form of S-adenosylmethionine decarboxylase.

PubMed

Tabor, C W; Tabor, H

1987-11-25

We have previously shown that the gene (speD) for S-adenosylmethionine decarboxylase is part of an operon that also contains the gene (speE) for spermidine synthase (Tabor, C. W., Tabor, H., and Xie, Q.-W. (1986) Proc. Natl. Acad. Sci. U. S. A. 83, 6040-6044). We have now determined the nucleotide sequence of this operon and have found that speD codes for a polypeptide of Mr = 30,400, which is considerably greater than the subunit size of the purified enzyme. Our studies show that S-adenosylmethionine decarboxylase is first formed as a Mr = 30,400 polypeptide and that this proenzyme is then cleaved at the Lys111-Ser112 peptide bond to form a Mr = 12,400 subunit and a Mr = 18,000 subunit. The latter subunit contains the pyruvoyl moiety that we previously showed is required for enzymatic activity. Both subunits are present in the purified enzyme. These conclusions are based on (i) pulse-chase experiments with a strain containing a speD+ plasmid which showed a precursor-product relationship between the proenzyme and the enzyme subunits, (ii) the amino acid sequence of the proenzyme form of S-adenosylmethionine decarboxylase (derived from the nucleotide sequence of the speD gene), and (iii) comparison of this sequence of the proenzyme with the N-terminal amino acid sequences of the two subunits of the purified enzyme reported by Anton and Kutny (Anton, D. L., and Kutny, R. (1987) J. Biol. Chem. 262, 2817-2822).

Beginning Special Educators: Characteristics, Qualifications, and Experiences. SPeNSE Summary Sheet.

ERIC Educational Resources Information Center

Billingsley, Bonnie S.

This report from the Study of Personnel Needs in Special Education (SPeNSE) provides a profile of the characteristics, qualifications, work experiences, and career plans of teachers with fewer than 3 years of experience. Findings indicate: (1) beginning teachers were more likely to work in suburban systems (50 percent); (2) the majority do not…

Comparative study for separation of atmospheric humic-like substance (HULIS) by ENVI-18, HLB, XAD-8 and DEAE sorbents: elemental composition, FT-IR, 1H NMR and off-line thermochemolysis with tetramethylammonium hydroxide (TMAH).

PubMed

Fan, Xingjun; Song, Jianzhong; Peng, Ping'an

2013-11-01

Humic-like substances (HULIS) are significant constituents of aerosols, and the isolation and characterization of HULIS by solid-phase extraction methods are dependent on the sorbents used. In this study, we used the following five methods: ENVI-18, HLB-M, HLB-N, XAD-8 and DEAE, to isolate atmospheric HULIS at an urban site. Then we conducted a comparative investigation of the HULIS chemical characteristics by means of elemental analysis, Fourier transform infrared spectroscopy, (1)H nuclear magnetic resonance spectroscopy and off-line thermochemolysis with tetramethylammonium hydroxide. The results indicate that HULIS isolated using different methods show many similarities in chemical composition and structure. Some differences were however also observed between the five isolated HULIS: HULISHLB-M contains a relatively high content of OCH group, compared to HULISENVI-18 and HULISXAD-8; HULISXAD-8 contains a relatively high content of hydrophobic and aromatic components, compared to HULISENVI-18 and HULISHLB-M; HULISDEAE contains the highest content of aromatic functional groups, as inferred by (1)H NMR spectra, but a great amount of salts generally present in the HULISDEAE and thereby limited the choices for characterizing the materials (i.e., elemental analysis and TMAH thermochemolysis); HULISHLB-N has relatively high levels of H and N, a high N/C atomic ratio, and includes N-containing functional groups, which suggests that it has been altered by 2% ammonia introduced in the eluents. In summary, we found that ENVI-18, HLB-M, and XAD-8 are preferable methods for isolation and characterization of HULIS in atmospheric aerosols. These results also suggest that caution is required when applying DEAE and HLB-N isolating methods for characterizing atmospheric HULIS. Copyright © 2013 Elsevier Ltd. All rights reserved.

Determination of DDT and metabolites in surface water and sediment using LLE, SPE, ACE and SE.

PubMed

Sibali, Linda L; Okonkwo, Jonathan O; Zvinowanda, Caliphs

2009-12-01

Surface water and sediment samples collected from Jukskei River in South Africa, were subjected to different extraction techniques, liquid-liquid (LLE), solid-phase extraction (SPE), activated carbon extraction (ACE) and soxhlet extraction (SE) for sediment. The samples were extracted with dichloromethane, cleaned in a silica gel column and the extracts quantified using a Varian 3800 GC-ECD. The percentage recovery test for 2,4'DDT, DDE and DDD and 4,4'DDT, DDE and DDD in water ranged from 80%-96% and 76%-95% (LLE); 56%-76% and 56%-70% (SPE) and 75%-84% (ACE), respectively; while that recoveries for sediment samples varied from 65%-95% for 2,4'DDT, DDE and DDD and 80%-91% for 4,4'DDT, DDE and DDD. The high recoveries exhibited by ACE compared very well with LLE and SE. This was not the case with SPE which exhibited the lowest value of recoveries for both 2,4 and 4,4'DDD, DDE and DDT standard samples. The mean concentrations of DDT and metabolites ranged from nd-1.10 μg/L, nd-0.80 μg/L, nd-1.21 μg/L and 1.92 μg/L for LLE, SPE, ACE and SE, respectively. The total DDT (2,4' and 4,4'-DDT) in water and sediment samples ranged from 1.20-3.25 μg/L and 1.82-5.24 μg/L, respectively. The low concentrations of the DDT metabolites obtained in the present study may suggest a recent contamination of the river by DDT.

Matrix solid-phase dispersion on column clean-up/pre-concentration as a novel approach for fast isolation of abuse drugs from human hair.

PubMed

Míguez-Framil, Martha; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar; Alvarez-Freire, Iván; Tabernero, María Jesús; Bermejo, Ana María

2010-10-08

A simple and fast sample pre-treatment method based on matrix solid-phase dispersion (MSPD) for isolating cocaine, benzoylecgonine (BZE), codeine, morphine and 6-monoacethylmorphine (6-MAM) from human hair has been developed. The MSPD approach consisted of using alumina (1.80 g) as a dispersing agent and 0.6M hydrochloric acid (4 mL) as an extracting solvent. For a fixed hair sample mass of 0.050 g, the alumina mass to sample mass ratio obtained was 36. A previously conditioned Oasis HLB cartridge (2 mL methanol, plus 2 mL ultrapure water, plus 1 mL of 0.2M/0.2M sodium hydroxide/boric acid buffer solution at pH 9.2) was attached to the end of the MSPD syringe for on column clean-up of the hydrochloric acid extract and for transferring the target compounds to a suitable solvent for gas chromatography (GC) analysis. Therefore, the adsorbed analytes were directly eluted from the Oasis HLB cartridges with 2 mL of 2% acetic acid in methanol before concentration by N(2) stream evaporation and dry extract derivatization with N-methyl-tert-butylsilyltrifluoroacetamide (BSTFA) and chlorotrimethylsilane (TMCS). The optimization/evaluation of all the factors affecting the MSPD and on column clean-up procedures has led to a fast sample treatment, and analytes extraction and pre-concentration can be finished in approximately 30 min. The developed method has been applied to eight hair samples from poli-drug abusers and measured analyte concentrations have been found to be statistically similar (95% confidence interval) to those obtained after a conventional enzymatic hydrolysis method (Pronase E). Copyright © 2010. Published by Elsevier B.V.

Geoenvironmental studies on conservation of archaeological sites at Siwa oasis, Egypt

NASA Astrophysics Data System (ADS)

Ibrahim, Hani A. M.; Kamh, Gamal E.

2006-02-01

Siwa oasis is located in the extreme western part of the Egyptian western desert. There are several archaeological sites in the oasis; the most distinct ones are Alexander the Great temple at Aghormi hill and the Gebel El Mota tomb excavations. They have suffered due to deterioration and cracks of different kinds and some parts are getting worse as rock falls occur. From field inspection and lab analysis, it is clear that lithology plays an important role on the extent of damage. Alexander the Great temple was built over the northern edge of Aghormi hill, which consists of two distinct beds—an upper limestone bed and a lower shale one. From field survey and laboratory analysis, the shale is considered as a high expanded bed and weak in its bearing capacity, as its clay content (mainly smectite) experienced swelling due to wetting from the ground water spring underneath. Consequently, the upper limestone bed suffered from map cracking associated with rock falls due to the differential settlement of the swelled lower shale one. The temple was threatened by slope instability and had experienced many cracks. At Gabal El Mota tomb excavations, it was noticed that a comparison of tombs of the same opening size revealed that those that excavated on shale beds had cracked much more than those that excavated on limestone. This may be attributed to the low bearing capacity of excavated shale walls. The remedial measures suggested to overcome the stability problems on these archaeological sites are grouting or construction of retaining walls.

[Effects of different disturbance modes on the morphological characteristics and aboveground biomass of Alhagi sparsifolia in oasis-desert ecotone].

PubMed

Li, Hai-Feng; Zeng, Fan-Jiang; Gui, Dong-Wei; An, Gui-Xiang; Liu, Zhen; Zhang, Li-Gang; Liu, Bo

2012-01-01

Taking Cele oasis at the southern fringe of Taklimakan Desert as a case, this paper studied the effects of different disturbances (burning in spring, cutting in spring, and cutting in fall) on the morphological characteristics and aboveground biomass of natural vegetation Alhagi sparsifolia in the ecotone of oasis-desert. Burning in spring decreased the A. sparsifolia plant height, crown width, and biomass significantly, being harmful to the regeneration and growth of the vegetation. Cutting in spring decreased the A. sparsifolia plant height, crown width, and biomass but increased the leaf biomass, thorn length, and thorn diameter, whereas cutting in fall decreased the plant height and crown width but increased the ramification amount and biomass of A. sparsifolia. Moderate cutting in fall could benefit the protection of A. sparsifolia at the southern fringe of Taklimakan Desert.

Perennial Antarctic lake ice: an oasis for life in a polar desert

NASA Technical Reports Server (NTRS)

Priscu, J. C.; Fritsen, C. H.; Adams, E. E.; Giovannoni, S. J.; Paerl, H. W.; McKay, C. P.; Doran, P. T.; Gordon, D. A.; Lanoil, B. D.; Pinckney, J. L.

1998-01-01

The permanent ice covers of Antarctic lakes in the McMurdo Dry Valleys develop liquid water inclusions in response to solar heating of internal aeolian-derived sediments. The ice sediment particles serve as nutrient (inorganic and organic)-enriched microzones for the establishment of a physiologically and ecologically complex microbial consortium capable of contemporaneous photosynthesis, nitrogen fixation, and decomposition. The consortium is capable of physically and chemically establishing and modifying a relatively nutrient- and organic matter-enriched microbial "oasis" embedded in the lake ice cover.

Perennial Antarctic lake ice: an oasis for life in a polar desert.

PubMed

Priscu, J C; Fritsen, C H; Adams, E E; Giovannoni, S J; Paerl, H W; McKay, C P; Doran, P T; Gordon, D A; Lanoil, B D; Pinckney, J L

1998-06-26

The permanent ice covers of Antarctic lakes in the McMurdo Dry Valleys develop liquid water inclusions in response to solar heating of internal aeolian-derived sediments. The ice sediment particles serve as nutrient (inorganic and organic)-enriched microzones for the establishment of a physiologically and ecologically complex microbial consortium capable of contemporaneous photosynthesis, nitrogen fixation, and decomposition. The consortium is capable of physically and chemically establishing and modifying a relatively nutrient- and organic matter-enriched microbial "oasis" embedded in the lake ice cover.

Moment Tensor Descriptions for Simulated Explosions of the Source Physics Experiment (SPE)

NASA Astrophysics Data System (ADS)

Yang, X.; Rougier, E.; Knight, E. E.; Patton, H. J.

2014-12-01

In this research we seek to understand damage mechanisms governing the behavior of geo-materials in the explosion source region, and the role they play in seismic-wave generation. Numerical modeling tools can be used to describe these mechanisms through the development and implementation of appropriate material models. Researchers at Los Alamos National Laboratory (LANL) have been working on a novel continuum-based-viscoplastic strain-rate-dependent fracture material model, AZ_Frac, in an effort to improve the description of these damage sources. AZ_Frac has the ability to describe continuum fracture processes, and at the same time, to handle pre-existing anisotropic material characteristics. The introduction of fractures within the material generates further anisotropic behavior that is also accounted for within the model. The material model has been calibrated to a granitic medium and has been applied in a number of modeling efforts under the SPE project. In our modeling, we use a 2D, axisymmetric layered earth model of the SPE site consisting of a weathered layer on top of a half-space. We couple the hydrodynamic simulation code with a seismic simulation code and propagate the signals to distances of up to 2 km. The signals are inverted for time-dependent moment tensors using a modified inversion scheme that accounts for multiple sources at different depths. The inversion scheme is evaluated for its resolving power to determine a centroid depth and a moment tensor description of the damage source. The capabilities of the inversion method to retrieve such information from waveforms recorded on three SPE tests conducted to date are also being assessed.

Magnetotelluric study of the Pahute Mesa and Oasis Valley regions, Nye County, Nevada

USGS Publications Warehouse

Schenkel, Clifford J.; Hildenbrand, Thomas G.; Dixon, Gary L.

1999-01-01

Magnetotelluric data delineate distinct layers and lateral variations above the pre-Tertiary basement. On Pahute Mesa, three resistivity layers associated with the volcanic rocks are defined: a moderately resistive surface layer, an underlying conductive layer, and a deep resistive layer. Considerable geologic information can be derived from the conductive layer which extents from near the water table down to a depth of approximately 2 km. The increase in conductivity is probably related to zeolite zonation observed in the volcanic rock on Pahute Mesa, which is relatively impermeable to groundwater flow unless fractured. Inferred faults within this conductive layer are modeled on several profiles crossing the Thirsty Canyon fault zone. This fault zone extends from Pahute Mesa into Oasis Valley basin. Near Colson Pond where the basement is shallow, the Thirsty Canyon fault zone is several (~2.5) kilometers wide. Due to the indicated vertical offsets associated with the Thirsty Canyon fault zone, the fault zone may act as a barrier to transverse (E-W) groundwater flow by juxtaposing rocks of different permeabilities. We propose that the Thirsty Canyon fault zone diverts water southward from Pahute Mesa to Oasis Valley. The electrically conductive nature of this fault zone indicates the presence of abundant alteration minerals or a dense network of open and interconnected fractures filled with electrically conductive groundwater. The formation of alteration minerals require the presence of water suggesting that an extensive interconnected fracture system exists or existed at one time. Thus, the fractures within the fault zone may be either a barrier or a conduit for groundwater flow, depending on the degree of alteration and the volume of open pore space. In Oasis Valley basin, a conductive surface layer, composed of alluvium and possibly altered volcanic rocks, extends to a depth of 300 to 500 m. The underlying volcanic layer, composed mostly of tuffs, fills the

A simple and selective method for determination of phthalate biomarkers in vegetable samples by high pressure liquid chromatography-electrospray ionization-tandem mass spectrometry.

PubMed

Zhou, Xi; Cui, Kunyan; Zeng, Feng; Li, Shoucong; Zeng, Zunxiang

2016-06-01

In the present study, solid-phase extraction cartridges including silica reversed-phase Isolute C18, polymeric reversed-phase Oasis HLB and mixed-mode anion-exchange Oasis MAX, and liquid-liquid extractions with ethyl acetate, n-hexane, dichloromethane and its mixtures were compared for clean-up of phthalate monoesters from vegetable samples. Best recoveries and minimised matrix effects were achieved using ethyl acetate/n-hexane liquid-liquid extraction for these target compounds. A simple and selective method, based on sample preparation by ultrasonic extraction and liquid-liquid extraction clean-up, for the determination of phthalate monoesters in vegetable samples by liquid chromatography/electrospray ionisation-tandem mass spectrometry was developed. The method detection limits for phthalate monoesters ranged from 0.013 to 0.120 ng g(-1). Good linearity (r(2)>0.991) between MQLs and 1000× MQLs was achieved. The intra- and inter-day relative standard deviation values were less than 11.8%. The method was successfully used to determine phthalate monoester metabolites in the vegetable samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of Radiation Transport Codes, HZETRN, HETC and FLUKA, Using the 1956 Webber SPE Spectrum

NASA Technical Reports Server (NTRS)

Heinbockel, John H.; Slaba, Tony C.; Blattnig, Steve R.; Tripathi, Ram K.; Townsend, Lawrence W.; Handler, Thomas; Gabriel, Tony A.; Pinsky, Lawrence S.; Reddell, Brandon; Clowdsley, Martha S.;

SPE-HPTLC of procyanidins from the barks of different species and clones of Salix.

PubMed

Pobłocka-Olech, Loretta; Krauze-Baranowska, Mirosława

2008-11-04

A SPE-HPTLC method was developed for the qualitative and quantitative analysis of procyanidin B(1) in willow barks. The chromatography was performed on HPTLC silica gel layer with the mobile phase chloroform-ethanol-formic acid (50:40:6 v/v/v), in the Automatic Developing Chamber-ADC 2. The methanol extracts from willow barks were purified by SPE method on RP-18 silica gel columns with methanol-water (7:93 v/v) as the eluent. The presence of procyanidin B(1) was revealed in the majority of investigated willow barks. The content of procyanidin B(1) varied from 0.26 mg/g in the extract of Salix purpurea clone 1067-2.24 mg/g in the extract of Salix alba clone 1100. The method was validated for linearity, precision, LOD, LOQ and repeatability.

OASYS (OrAnge SYnchrotron Suite): an open-source graphical environment for x-ray virtual experiments

NASA Astrophysics Data System (ADS)

Rebuffi, Luca; Sanchez del Rio, Manuel

2017-08-01

The evolution of the hardware platforms, the modernization of the software tools, the access to the codes of a large number of young people and the popularization of the open source software for scientific applications drove us to design OASYS (ORange SYnchrotron Suite), a completely new graphical environment for modelling X-ray experiments. The implemented software architecture allows to obtain not only an intuitive and very-easy-to-use graphical interface, but also provides high flexibility and rapidity for interactive simulations, making configuration changes to quickly compare multiple beamline configurations. Its purpose is to integrate in a synergetic way the most powerful calculation engines available. OASYS integrates different simulation strategies via the implementation of adequate simulation tools for X-ray Optics (e.g. ray tracing and wave optics packages). It provides a language to make them to communicate by sending and receiving encapsulated data. Python has been chosen as main programming language, because of its universality and popularity in scientific computing. The software Orange, developed at the University of Ljubljana (SLO), is the high level workflow engine that provides the interaction with the user and communication mechanisms.

Development of low-cost technology for the removal of iron and manganese from ground water in siwa oasis.

PubMed

El-Naggar, Hesham M

2010-01-01

Ground water is the only water resource for Siwa Oasis. It is obtained from natural freshwater wells and springs fed by the Nubian aquifer. Water samples collected from Siwa Oasis had relatively higher iron (Fe) and manganese (Mn) than the permissible limits specified in WHO Guidelines and Egyptian Standards for drinking water quality. Aeration followed by sand filtration is the most commonly used method for the removal of iron from ground water. The study aimed at development of low-cost technology for the removal of iron and manganese from ground water in Siwa Oasis. The study was carried out on Laboratory-scale columns experiments sand filters with variable depths of 15, 30, 45, 60, 75, 90 cm and three graded types of sand were studied. The graded sand (E.S. =0.205 mm, U.C. =3.366, depth of sand = 60 cm and filtration rate = 1.44 m3/m2/hr) was the best type of filter media. Iron and manganese concentrations measured in ground water with aeration only, decreased with an average removal percentage of 16%, 13% respectively. Iron and manganese concentrations after filtration with aeration came down to 0.1123, 0.05 mg/L respectively in all cases from an initial concentration of 1.14, 0.34 mg/L respectively. Advantages of such treatment unit included simplicity, low cost design, and no need for chemical addition. In addition, the only maintenance required was periodic washing of the sand filter or replacement of the sand in order to maintain reasonable flow rate through the system.

Quantitative assessment of the impact of an inter-basin surface-water transfer project on the groundwater flow and groundwater-dependent eco-environment in an oasis in arid northwestern China

NASA Astrophysics Data System (ADS)

Zhu, Xiaobin; Wu, Jichun; Nie, Huijun; Guo, Fei; Wu, Jianfeng; Chen, Kouping; Liao, Penghui; Xu, Hongxia; Zeng, Xiankui

2018-06-01

Inter-basin water transfer projects (IBWTPs) can involve basins as water donors and water receivers. In contrast to most studies on IBWTPs, which mainly impact the surface-water eco-environment, this study focuses on the impacts of an IBWTP on groundwater and its eco-environment in a water donor basin in an arid area, where surface water and groundwater are exchanged. Surface water is assumed to recharge groundwater and a groundwater numerical simulation model was constructed using MODFLOW. The model was used to quantitatively evaluate the impact of an IBWTP located in the upstream portion of Nalenggele River (the biggest river in the Qaidam basin, Northwest China). The impact involved decrease in spring flow, drawdown of groundwater, reduction in oasis area, and an increase in species replacement of oasis vegetation in the midstream and downstream of the river. Results show that the emergence sites of springs at the front of the oasis will move 2-5 km downstream, and the outflow of springs will decrease by 42 million m3/a. The maximum drawdown of groundwater level at the front of the oasis will be 3.6 m and the area across which groundwater drawdown exceeds 2.0 m will be about 59.02 km2, accounting for 2.71% of the total area of the oasis. Under such conditions, reeds will gradually be replaced by Tamarix, shrubs, and other alternative plant species. These findings have important implications for the optimization of water resource allocation and protection of the eco-environment in arid regions.

Reflection processing of the large-N seismic data from the Source Physics Experiment (SPE)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paschall, Olivia C.

2016-07-18

The purpose of the SPE is to develop a more physics-based model for nuclear explosion identification to understand the development of S-waves from explosion sources in order to enhance nuclear test ban treaty monitoring.

False color image of Safsaf Oasis in southern Egypt

NASA Technical Reports Server (NTRS)

1994-01-01

This is a false color image of the uninhabited Safsaf Oasis in southern Egypt near the Egypt/Sudan border. It was produced from data obtained from the L-band and C-band radars that are part of the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar onboard the Shuttle Endeavour on April 9, 1994. The image is centered at 22 degrees North latitude, 29 degrees East longitude. It shows detailed structures of bedrock, and the dark blue sinuous lines are braided channels that occupy part of an old broad river valley. Virtually everything visible on this radar composite image cannot be seen either when standing on the ground or when viewing photographs or satellite images such as Landsat. The Jet Propulsion Laboratory alternative photo number is P-43920.

Use of solid phase extraction (SPE) to evaluate in vitro skin permeation of aescin.

PubMed

Montenegro, L; Carbone, C; Giannone, I; Puglisi, G

2007-05-01

The aim of this work was to evaluate the feasibility of assessing aescin in vitro permeation through human skin by determining the amount of aescin permeated using conventional HPLC procedures after extraction of skin permeation samples by means of solid phase extraction (SPE). Aescin in vitro skin permeation was assessed from aqueous solutions and gels using both Franz-type diffusion cells and flow-through diffusion cells. The SPE method used was highly accurate (mean accuracy 99.66%), highly reproducible (intra-day and inter-day variations lower than 2.3% and 2.2%, respectively) and aescin recovery from normal saline was greater than 99%. The use of Franz-type diffusion cells did not allow us to determine aescin flux values through excised human skin, therefore aescin skin permeation parameters could be calculated only using flow-through diffusion cells. Plotting the cumulative amount of aescin permeated as a function of time, linear relationships were obtained from both aqueous solution and gel using flow-through diffusion cells. Aescin flux values through excised human skin from aqueous gel were significantly lower than those observed from aqueous solution (p < 0.05). Calculating aescin percutaneous absorption parameters we evidenced that aescin partition coefficient was lower from the aqueous gel with respect to the aqueous solution. Therefore, the SPE method used in this study was suitable to determine aescin in vitro skin permeation parameters from aqueous solutions and gels using a conventional HPLC method for the analysis of the skin permeation samples.

Near-Field to Far-Field Uncertainty Propagation and Quantification of Ground Motions Generated by the Source Physics Experiments (SPE)

NASA Astrophysics Data System (ADS)

Antoun, T.; Ezzedine, S. M.; Vorobiev, O.; Pitarka, A.; Hurley, R.; Hirakawa, E. T.; Glenn, L.; Walter, W. R.

2016-12-01

LLNL has developed a framework for uncertainty propagation and quantification using HPC numerical codes to simulate end-to-end, from source to receivers, the ground motions observed during the Source Physics Experiments (SPE) conducted in fractured granitic rock at the Nevada National Security Site (NNSS). SPE includes six underground chemical explosions designed with different yields initiated at different depths. To date we have successfully applied this framework to explain the near-field shear motions observed in the vicinity of SPE3 thru SPE5. However, systematic uncertainty propagation to the far-field seismic receiver has not been addressed yet. In the current study, we used a coupling between the non-linear inelastic hydrodynamic regime in the near-field and the seismic elastic regime in the far-field to conduct the analysis. Several realizations of the stochastic discrete fracture network were generated conditional to the observed sparse data. These realizations were then used to calculate the ground motions generated from the SPE shots up to the elastic radius. The latter serves as the handshake interface for the far-field simulations. By creating several realizations of near-field responses one can embed those sources into the far-field elastic wave code and further the uncertainty propagation to the receivers. We will present a full assessment from end-to-end for the near- and far-field measurements. Separate analyses of the effect of the different conceptual geological models are also carried over using a nested Monte Carlo scheme. We compare the observed frequency content at several gages with the simulated ones. We conclude that both regions experience different sampling of frequencies: small features are relevant to near-field simulations while larger feature are more dominant at the far-field. We finally rank the primary sensitive parameters for both regions to drive and refine the field characterization data collection.

LC-QTOF MS screening of more than 1,000 licit and illicit drugs and their metabolites in wastewater and surface waters from the area of Bogotá, Colombia.

PubMed

Hernández, Félix; Ibáñez, María; Botero-Coy, Ana-María; Bade, Richard; Bustos-López, Martha Cristina; Rincón, Javier; Moncayo, Alejandro; Bijlsma, Lubertus

2015-08-01

A large screening of around 1,000 emerging contaminants, focused on licit and illicit drugs and their metabolites, has been made in urban wastewaters (both influent and effluent) and surface waters from the area of Bogotá, Colombia. After a simple generic solid-phase extraction (SPE) step with Oasis hydrophilic-lipophilic balanced (HLB) cartridges, analyses were made by ultra high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS) under MS(E) mode (sequential acquisition of mass spectra at low energy (LE) and high collision energy (HE)). Accurate mass measurements and the information provided by MS(E) on the presence of the (de)protonated molecule and fragment ions allowed the reliable identification of the compounds detected, even without reference standards being available in some cases (tentative identification). The compounds most frequently found were acetaminophen/paracetamol, carbamazepine and its dihydro-dihydroxylated metabolite, clarithromycin, diclofenac, ibuprofen, gemfibrozil, lincomycin, losartan, valsartan, the two metabolites of metamizole (4-acetamido-antipyrine and 4-formylamino-antipyrine), sucralose, and cocaine and its main metabolite benzoylecgonine. Caffeine, the sweetener saccharin, and two hydroxylated metabolites of losartan were tentatively identified in almost all samples analyzed. Pharmaceutical lidocaine was tentatively identified and subsequently confirmed with reference standard. For the first time, a general overview of the occurrence of drugs and their metabolites in the aquatic environment of Colombia has been reported. In the near future, target methodologies, typically based on liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), will need to be set up for accurate and sensitive quantification of the contaminants selected on the basis on the information provided in the present paper.

[Simultaneous determination of nine estrogens in eel by ultrafast liquid chromatography-tandem mass spectrometry with isotope dilution technique and solid-phase extraction].

PubMed

Chen, Xiaohong; Yao, Shanshan; Li, Xiaoping; Zhao, Yonggang; Jin, Micong

2012-11-01

Developing a rapid and sensitive analytical method based on ultrafast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) with solid-phase extraction (SPE) for the simultaneous determination of nine estrogens (dienestrol, diethylstilbestrol, estrone, hexestrol, 17-alpha-estradiol, 17-beta-estradiol, estriol, 17alpha-ethinylestradiol and estradiol valerate) in eel. After the sample was extracted by acetonitrile and cleaned by Waters Oasis HLB solid-phase extraction cartridge, the UFLC separation was performed on a Shim-pack XR-ODS II column (100 mm x 2.0 mm, 2.2 microm) with a linear gradient elution program of methanol solution containing 0.04% ammonia (v/v) and 0.04% ammonia aqueous solution (v/v) as the mobile phase. Electrospray ionization was applied and operated in the negative multiple reaction monitoring (MRM) mode. The quantitation was used by isotope internal standard dilution technique. The results showed that the limits of quantitation (LOQs, S/N(10) were in the range of 0.07-0.4 microg/kg, the calibration curves were in good linearities for the nine analytes in the range of 0.5-50.0 microg/L with the correlative coefficients (r2) more than 0.998, the recoveries were between 81.0% and 110.0% with the relative standard deviations (RSDs) of 1.92%-8.24%. Additional, the mass spectra characterization of the nine estrogens was discussed and the fragmentation pathways were speculated. The developed method is rapid, sensitive, specific and reproducible, and adapts not only to the simultaneous determination of the nine trace estrogens including the epimer of 17-alpha-estradiol and 17-beta-estradiol but also to the identified detection in other fish tissues.

[Simultaneous determination of seven high risk pesticide residues in royal jelly by high performance liquid chromatography-tandem mass spectrometry].

PubMed

Li, Yinghong; Zhou, Ping; Xu, Quanhua; Zhao, Huan; Shao, Qiaoyun

2018-02-08

A method was developed for the simultaneous determination of seven high risk pesticides in the royal jelly, eg. tau-fluvalinate, triadimenol, coumaphos, haloxyfop, carbendazim, thiophanate-ethyl and thiophanate-methyl by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). First, the royal jelly samples were extracted with acetonitrile under alkaline conditions. After dehydration by anhydrous sodium sulfate, the extracts were enriched and purified through solid-phase extraction (SPE) with Oasis HLB cartridges. Finally, the pesticides were detected by HPLC-MS/MS method. The separation was carried out on a Venusil MP C18 column with gradient elution. Methanol (containing 0.1% (v/v) formic acid) and 0.5 mmol/L ammonium acetate aqueous solution (containing 0.1% (v/v) formic acid) were used as the mobile phases. The detection was achieved using electrospray ionization in positive ion (ESI + ) mode and multiple reaction monitoring (MRM) mode for data collection. Quantification was carried out using internal standard method. The results showed that the seven high risk pesticides were linear in the range of 5-100 μg/kg. The linear correlation coefficients ( r 2 ) were 0.9921-0.9996. The limits of detection (LODs) and limits of quantification (LOQs) of the seven high risk pesticides were 0.5-2.0 μg/kg and 1.0-5.0 μg/kg, respectively. The average recoveries at the three spiked levels were 80.5%-101.3%, and the relative standard deviations were 3.6%-9.4% ( n =3). This method is simple, effective and sensitive, and is suitable for the determination of the pesticide residues in royal jelly.

High throughput HPLC-ESI(-)-MS/MS methodology for mercapturic acid metabolites of 1,3-butadiene: Biomarkers of exposure and bioactivation.

PubMed

Kotapati, Srikanth; Esades, Amanda; Matter, Brock; Le, Chap; Tretyakova, Natalia

2015-11-05

1,3-Butadiene (BD) is an important industrial and environmental carcinogen present in cigarette smoke, automobile exhaust, and urban air. The major urinary metabolites of BD in humans are 2-(N-acetyl-L-cystein-S-yl)-1-hydroxybut-3-ene/1-(N-acetyl-L-cystein-S-yl)-2-hydroxybut-3-ene (MHBMA), 4-(N-acetyl-L-cystein-S-yl)-1,2-dihydroxybutane (DHBMA), and 4-(N-acetyl-L-cystein-S-yl)-1,2,3-trihydroxybutyl mercapturic acid (THBMA), which are formed from the electrophilic metabolites of BD, 3,4-epoxy-1-butene (EB), hydroxymethyl vinyl ketone (HMVK), and 3,4-epoxy-1,2-diol (EBD), respectively. In the present work, a sensitive high-throughput HPLC-ESI(-)-MS/MS method was developed for simultaneous quantification of MHBMA and DHBMA in small volumes of human urine (200 μl). The method employs a 96 well Oasis HLB SPE enrichment step, followed by isotope dilution HPLC-ESI(-)-MS/MS analysis on a triple quadrupole mass spectrometer. The validated method was used to quantify MHBMA and DHBMA in urine of workers from a BD monomer and styrene-butadiene rubber production facility (40 controls and 32 occupationally exposed to BD). Urinary THBMA concentrations were also determined in the same samples. The concentrations of all three BD-mercapturic acids and the metabolic ratio (MHBMA/(MHBMA+DHBMA+THBMA)) were significantly higher in the occupationally exposed group as compared to controls and correlated with BD exposure, with each other, and with BD-hemoglobin biomarkers. This improved high throughput methodology for MHBMA and DHBMA will be useful for future epidemiological studies in smokers and occupationally exposed workers. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Photomosaics and logs of trenches on the San Andreas Fault, Thousand Palms Oasis, California

USGS Publications Warehouse

Fumal, Thomas E.; Frost, William T.; Garvin, Christopher; Hamilton, John C.; Jaasma, Monique; Rymer, Michael J.

2004-01-01

We present photomosaics and logs of the walls of trenches excavated for a paleoseismic study at Thousand Palms Oasis (Fig. 1). The site is located on the Mission Creek strand of the San Andreas fault zone, one of two major active strands of the fault in the Indio Hills along the northeast margin of the Coachella Valley (Fig. 2). The Coachella Valley section is the most poorly understood major part of the San Andreas fault with regard to slip rate and timing of past large-magnitude earthquakes, and therefore earthquake hazard. No large earthquakes have occurred for more than three centuries, the longest elapsed time for any part of the southern San Andreas fault. In spite of this, the Working Group on California Earthquake Probabilities (1995) assigned the lowest 30-year conditional probability on the southern San Andreas fault to the Coachella Valley. Models of the behavior of this part of the fault, however, have been based on very limited geologic data. The Thousand Palms Oasis is an attractive location for paleoseismic study primarily because of the well-bedded late Holocene sedimentary deposits with abundant layers of organic matter for radiocarbon dating necessary to constrain the timing of large prehistoric earthquakes. Previous attempts to develop a chronology of paleoearthquakes for the region have been hindered by the scarcity of in-situ 14C-dateable material for age control in this desert environment. Also, the fault in the vicinity of Thousand Palms Oasis consists of a single trace that is well expressed, both geomorphically and as a vegetation lineament (Figs. 2, 3). Results of our investigations are discussed in Fumal et al. (2002) and indicate that four and probably five surface-rupturing earthquakes occurred along this part of the fault during the past 1200 years. The average recurrence time for these earthquakes is 215 ± 25 years, although interevent times may have been as short as a few decades or as long as 400 years. Thus, although the elapsed

Diversity and cold adaptation of microorganisms isolated from the Schirmacher Oasis, Antarctica

NASA Astrophysics Data System (ADS)

Mojib, Nazia; Bej, Asim K.; Hoover, Richard

2008-08-01

We have investigated the feasibility of the PCR amplification of the 16S rRNA genes from eubacteria and Archea on samples collected on Whatman FTA filters from Schirmacher Oasis for the study of culture-independent analysis of the microbial diversity. Both conventional PCR and real-time TaqmaTM PCR successfully amplified the targeted genes. A number of diverse groups of psychrotolerant microorganisms with various pigments have been isolated when cultured on agar medium. 16S rRNA gene analysis of these isolates helped us to identify closest taxonomic genus Pseudomonas, Frigoribacterium, Arthrobacter, Flavobacterium, and Janthinobacterium. It is possible that the pigments play protective role from solar UV radiation, which is prevalent in Antarctic continent especially during Austral summer months. Study of the expression of cold adaptive protein CapB and ice-binding protein IBP using western blots showed positive detection of both or either of these proteins in 6 out of 8 isolates. Since the CapB and IBP protein structure greatly varies in microorganisms, it is possible that the 2 isolates with negative results could have a different class of these proteins. The expression of the CapB and the IBP in these isolates suggest that these proteins are essential for the survival in the Antarctic cold and subzero temperatures and protect themselves from freeze-damage. The current study provided sufficient data to further investigate the rich and diverse biota of psychrotolerant extremophiles in the Antarctic Schirmacher Oasis using both culture-independent and culture-based approaches; and understand the mechanisms of cold tolerance.

Ternary mixed-mode silica sorbent of solid-phase extraction for determination of basic, neutral and acidic drugs in human serum.

PubMed

Jin, Shupei; Qiao, Yinghua; Xing, Jun

2018-06-01

In this study, a ternary mixed-mode silica sorbent (TMSS) with octamethylene, carboxyl, and amino groups was prepared via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction and a subsequent reduction of azide to primary amine. While used in solid-phase extraction (SPE), the retention behavior of TMSS towards a total of nine kinds of basic, neutral, and acidic drugs was investigated in detail. The results revealed that hydrophobic, ion-exchange interaction, and electrostatic repulsion between TMSS and the analytes were closely related to the retention behavior of TMSS. Besides, the log K ow value of the analyte was also a factor influencing the retention behavior of analytes on TMSS. The nine analytes could be retained by TMSS simultaneously and then, were eluted into two fractions according to the acid-base property of the analytes for further determinations. The acidic and neutral analytes were in one fraction, and the basic ones in the other fraction. When used to treat the human serum spiked with the nine drugs, TMSS offered higher recoveries than BakerBond CBA and comparable recoveries to Oasis WCX. It should be noted TMSS had better purifying capability for human serum than Oasis WCX. Under the optimized SPE conditions, a method of SPE hyphenated to high-performance liquid chromatography-ultraviolet detection (HPLC-UV) for determination of the basic, neutral, and acidic drugs spiked in human serum was established. For the nine drugs, the linear ranges were all between 5.0 and 1000 μg L -1 with correlation coefficients (R 2 ) above 0.9990, and the limits of detection (LODs) were in the range of 0.8-2.3 μg L -1 . The intra-day and inter-day relative standard deviations (RSDs) were less than 5.3 and 8.8%, respectively. Graphical abstract Treating drugs in human serum by SPE with ternary mixed-mode silica sorbent.

DroSpeGe: rapid access database for new Drosophila species genomes.

PubMed

Gilbert, Donald G

2007-01-01

The Drosophila species comparative genome database DroSpeGe (http://insects.eugenes.org/DroSpeGe/) provides genome researchers with rapid, usable access to 12 new and old Drosophila genomes, since its inception in 2004. Scientists can use, with minimal computing expertise, the wealth of new genome information for developing new insights into insect evolution. New genome assemblies provided by several sequencing centers have been annotated with known model organism gene homologies and gene predictions to provided basic comparative data. TeraGrid supplies the shared cyberinfrastructure for the primary computations. This genome database includes homologies to Drosophila melanogaster and eight other eukaryote model genomes, and gene predictions from several groups. BLAST searches of the newest assemblies are integrated with genome maps. GBrowse maps provide detailed views of cross-species aligned genomes. BioMart provides for data mining of annotations and sequences. Common chromosome maps identify major synteny among species. Potential gain and loss of genes is suggested by Gene Ontology groupings for genes of the new species. Summaries of essential genome statistics include sizes, genes found and predicted, homology among genomes, phylogenetic trees of species and comparisons of several gene predictions for sensitivity and specificity in finding new and known genes.

Colorimetric-Solid Phase Extraction Technology for Water Quality Monitoring: Evaluation of C-SPE and Debubbling Methods in Microgravity

NASA Technical Reports Server (NTRS)

Hazen-Bosveld, April; Lipert, Robert J.; Nordling, John; Shih, Chien-Ju; Siperko, Lorraine; Porter, Marc D.; Gazda, Daniel B.; Rutz, Jeff A.; Straub, John E.; Schultz, John R.;

User's Guide to OASIS, Oceanic and Atmospheric Scientific Information System. Key to Oceanic and Atmospheric Information Sources No. 1.

ERIC Educational Resources Information Center

National Oceanic and Atmospheric Administration (DOC), Washington, DC. Environmental Data Service.

OASIS (Oceanic and Atmospheric Scientific Information System) is an information retrieval service that furnishes ready reference to the technical literature and research efforts concerning the environmental sciences and marine and coastal resources. It provides computerized searches of both NOAA (National Oceanic and Atmospheric Administration)…

Broad-spectrum antibiotic or G-CSF as potential countermeasures for impaired control of bacterial infection associated with an SPE exposure during spaceflight.

PubMed

Li, Minghong; Holmes, Veronica; Ni, Houping; Sanzari, Jenine K; Romero-Weaver, Ana L; Lin, Liyong; Carabe-Fernandez, Alejandro; Diffenderfer, Eric S; Kennedy, Ann R; Weissman, Drew

2015-01-01

A major risk for astronauts during prolonged space flight is infection as a result of the combined effects of microgravity, situational and confinement stress, alterations in food intake, altered circadian rhythm, and radiation that can significantly impair the immune system and the body's defense systems. We previously reported a massive increase in morbidity with a decrease in the ability to control a bacterial challenge when mice were maintained under hindlimb suspension (HS) conditions and exposed to solar particle event (SPE)-like radiation. HS and SPE-like radiation treatment alone resulted in a borderline significant increase in morbidity. Therefore, development and testing of countermeasures that can be used during extended space missions in the setting of exposure to SPE radiation becomes a serious need. In the present study, we investigated the efficacy of enrofloxacin (an orally bioavailable antibiotic) and Granulocyte colony stimulating factor (G-CSF) (Neulasta) on enhancing resistance to Pseudomonas aeruginosa infection in mice subjected to HS and SPE-like radiation. The results revealed that treatment with enrofloxacin or G-CSF enhanced bacterial clearance and significantly decreased morbidity and mortality in challenged mice exposed to suspension and radiation. These results establish that antibiotics, such as enrofloxacin, and G-CSF could be effective countermeasures to decrease the risk of bacterial infections after exposure to SPE radiation during extended space flight, thereby reducing both the risk to the crew and the danger of mission failure.

Matrix solid phase dispersion assisted enzymatic hydrolysis as a novel approach for cocaine and opiates isolation from human hair.

PubMed

Míguez-Framil, Martha; Cabarcos, Pamela; Tabernero, María Jesús; Bermejo, Ana María; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

2013-11-05

The possibility of assisting enzymatic hydrolysis (EH) procedures by sample disruption mechanisms inherent to matrix solid phase dispersion (MSPD) has been explored in the current study. EH of hair specimens from poly-drug abusers was assisted by dispersing/blending the sample (0.05 g) with alumina (2.25 g) before loading the dissolved enzyme (6 mL of 1 mg mL(-1) Pronase E in 1.4 M/1.4 M Tris/HCl, pH 7.3) through the hair-alumina solid phase packaged inside a disposable MSPD syringe. The MSPD-EH method was developed, and it proved to offer quantitative results when isolating cocaine, benzoylecgonine (BZE), codeine, morphine and 6-monoacethylmorphine (6-MAM) from human hair samples. The procedure allows an on column clean-up/pre-concentration procedure of the isolated targets by attaching a previously conditioned Oasis HLB cartridge to the end of the MSPD syringe. The EH procedure of human hair with Pronase E can therefore be shortened to approximately 30 min. Within this time, sample blending/dispersion, MSPD syringe package, elution (EH when dissolved Pronase E is passing through the sample-dispersant bed), and extract clean-up and target pre-concentration stages are achieved. Gas chromatography-mass spectrometry (GC-MS) was used for determining each target after elution from the Oasis HLB cartridges with 2 mL of 2% (v/v) acetic acid in methanol, concentration by N2 stream evaporation, and dried extract derivatization with N-methyl-tert-butylsilyltrifluoroacetamide (BSTFA) and chlorotrimethylsilane (TMCS). The method was validated according to the guidance for bioanalytical method validation of the US Department of Health and Human Services, Food and Drug Administration. The simplicity of the proposed approach makes it a useful procedure for screening/quantifying drugs of abuse in hair specimens from poly-drug abusers. Copyright © 2013 Elsevier B.V. All rights reserved.

The SpeX Prism Library for Ultracool Dwarfs: A Resource for Stellar, Exoplanet and Galactic Science and Student-Led Research

NASA Astrophysics Data System (ADS)

Burgasser, Adam

The NASA Infrared Telescope Facility's (IRTF) SpeX spectrograph has been an essential tool in the discovery and characterization of ultracool dwarf (UCD) stars, brown dwarfs and exoplanets. Over ten years of SpeX data have been collected on these sources, and a repository of low-resolution (R 100) SpeX prism spectra has been maintained by the PI at the SpeX Prism Spectral Libraries website since 2008. As the largest existing collection of NIR UCD spectra, this repository has facilitated a broad range of investigations in UCD, exoplanet, Galactic and extragalactic science, contributing to over 100 publications in the past 6 years. However, this repository remains highly incomplete, has not been uniformly calibrated, lacks sufficient contextual data for observations and sources, and most importantly provides no data visualization or analysis tools for the user. To fully realize the scientific potential of these data for community research, we propose a two-year program to (1) calibrate and expand existing repository and archival data, and make it virtual-observatory compliant; (2) serve the data through a searchable web archive with basic visualization tools; and (3) develop and distribute an open-source, Python-based analysis toolkit for users to analyze the data. These resources will be generated through an innovative, student-centered research model, with undergraduate and graduate students building and validating the analysis tools through carefully designed coding challenges and research validation activities. The resulting data archive, the SpeX Prism Library, will be a legacy resource for IRTF and SpeX, and will facilitate numerous investigations using current and future NASA capabilities. These include deep/wide surveys of UCDs to measure Galactic structure and chemical evolution, and probe UCD populations in satellite galaxies (e.g., JWST, WFIRST); characterization of directly imaged exoplanet spectra (e.g., FINESSE), and development of low

[Determination of dimethyl fumarate in bakery food by d-SPE-HPLC-PDA].

PubMed

Yang, Jie; Luo, Mengtian; Feng, Di; Miao, Hong; Song, Shufeng; Zhao, Yunfeng

2015-05-01

To establish a simple and rapid pretreatment method with dispersive solid phase extraction ( d-SPE) by HPLC for determination of dimethyl fumarate in bakery foods. Dimethyl fumarate in samples was ultrasonically extracted by methanol, and cleaned up with d-SPE. Then, it was separated on C18 chromatographic column (4.6 mm x 25 mm, 5 μm) with a mixture of methanol--0.03 mol/L sodium acetate and 0.008 mol/L tetrabutyl ammonium bromide (40: 60, V/V) as mobile phase. The photodiode array detector was used in the determination under λ = 220 nm. In the linear range of 0.1 -25 μg/ml, the correlation coefficients was r > 0.999, and the average recoveries of the spiked samples were in the range of 82.8% - 107.5% with relative standard deviations (RSD) in the range of 3.30% - 7.30% (n = 6). The limit of detection ( LOD) was 0.4 mg/kg, and the limit of quantification was 1.0 mg/kg. The method is simple, rapid, sensitive and accurate, and suitable for determine dimethyl fumarate in bakery foods.

Liquid Metering Centrifuge Sticks (LMCS): A Centrifugal Approach to Metering Known Sample Volumes for Colorimetric Solid Phase Extraction (C-SPE)

NASA Technical Reports Server (NTRS)

Gazda, Daniel B.; Schultz, John R.; Clarke, Mark S.

2007-01-01

Phase separation is one of the most significant obstacles encountered during the development of analytical methods for water quality monitoring in spacecraft environments. Removing air bubbles from water samples prior to analysis is a routine task on earth; however, in the absence of gravity, this routine task becomes extremely difficult. This paper details the development and initial ground testing of liquid metering centrifuge sticks (LMCS), devices designed to collect and meter a known volume of bubble-free water in microgravity. The LMCS uses centrifugal force to eliminate entrapped air and reproducibly meter liquid sample volumes for analysis with Colorimetric Solid Phase Extraction (C-SPE). C-SPE is a sorption-spectrophotometric platform that is being developed as a potential spacecraft water quality monitoring system. C-SPE utilizes solid phase extraction membranes impregnated with analyte-specific colorimetric reagents to concentrate and complex target analytes in spacecraft water samples. The mass of analyte extracted from the water sample is determined using diffuse reflectance (DR) data collected from the membrane surface and an analyte-specific calibration curve. The analyte concentration can then be calculated from the mass of extracted analyte and the volume of the sample analyzed. Previous flight experiments conducted in microgravity conditions aboard the NASA KC-135 aircraft demonstrated that the inability to collect and meter a known volume of water using a syringe was a limiting factor in the accuracy of C-SPE measurements. Herein, results obtained from ground based C-SPE experiments using ionic silver as a test analyte and either the LMCS or syringes for sample metering are compared to evaluate the performance of the LMCS. These results indicate very good agreement between the two sample metering methods and clearly illustrate the potential of utilizing centrifugal forces to achieve phase separation and metering of water samples in microgravity.

Electrochemical hydrogenation of thiophene on SPE electrodes

NASA Astrophysics Data System (ADS)

Huang, Haiyan; Yuan, Penghui; Yu, Ying; Chung, Keng H.

2017-01-01

Electrochemical reduction desulfurization is a promising technology for petroleum refining which is environmental friendly, low cost and able to achieve a high degree of automation. Electrochemical hydrogenation of thiophene was performed in a three-electrode system which SPE electrode was the working electrode. The electrochemical desulfurization was studied by cyclic voltammetry and bulk electrolysis with coulometry (BEC) techniques. The results of cyclic voltammetry showed that the electrochemical hydrogenation reduction reaction occurred at -0.4V. The BEC results showed that the currents generated from thiophene hydrogenation reactions increased with temperature. According to Arrhenius equation, activation energy of thiophene electrolysis was calculated and lower activation energy value indicated it was diffusion controlled reaction. From the products of electrolytic reactions, the mechanisms of electrochemical hydrogenation of thiophene were proposed, consisting of two pathways: openingring followed by hydrogenation, and hydrogenation followed by ring opening.

"Seeing Another/Seeing Oneself": Nondisabled Audiences' Perspectives on Disability in Two South Korean Films, "Oasis" (2002) and "Malaton" (2005)

ERIC Educational Resources Information Center

Woo, Chung Wan

2012-01-01

Using qualitative research methods, this dissertation closely examines discourses and representations of disability from the cinematic images of disabled characters and their families in two South Korean films, "Oasis" (C. Lee, 2002) and "Malaton" (Y. Jung, 2005) as well as from the responses of nineteen Korean graduate…

Determination of bisphenol A in human serum by high-performance liquid chromatography with multi-electrode electrochemical detection.

PubMed

Inoue, K; Kato, K; Yoshimura, Y; Makino, T; Nakazawa, H

2000-11-10

A simple and sensitive method using high-performance liquid chromatography with multi-electrode electrochemical detection (HPLC-ED) including a coulometric array of four electrochemical sensors has been developed for the determination of bisphenol A in water and human serum. For good separation and detection of bisphenol A, a CAPCELL PAK UG 120 C18 reversed-phase column and a mobile phase consisting of 0.3% phosphoric acid-acetonitrile (60:40) were used. The detection limit obtained by the HPLC-ED method was 0.01 ng/ml (0.5 pg), which was more than 3000-times higher than the detection limit obtained by the ultraviolet (UV) method, and more than 200-times higher than the detection limit obtained by the fluorescence (FL) method. Bisphenol A in water and serum samples was pretreated by solid-phase extraction (SPE) after removing possible contamination derived from a plastic SPE cartridges and water used for the pretreatment. A trace amount (ND approximately 0.013 ng/ml) of bisphenol A was detected from the parts of cartridges (filtration column, sorbent bed and frits) by extraction with methanol, and it was completely removed by washing with at least 15 ml of methanol in the operation process. The concentrations of bisphenol A in tap water and Milli-Q-purified water were found to be 0.01 and 0.02 ng/ml, respectively. For that reason, bisphenol A-free water was made to trap bisphenol A in water using an Empore disk. In every pretreatment, SPE methods using bisphenol A-free water and washing with 15 ml of methanol were done in water and serum samples. The yields obtained from the recovery tests using water to which 0.5 or 0.05 ng/ml of bisphenol A was added were 83.8 to 98.2%, and the RSDs were 3.4 to 6.1%, respectively. The yields obtained from the recovery tests by OASIS HLB using serum to which 1.0 ng/ml or 0.1 ng/ml of bisphenol A was added were 79.0% and 87.3%, and the RSDs were 5.1% and 13.5%, respectively. The limits of quantification in water and serum sample

Extinction dynamics of a discrete population in an oasis.

PubMed

Berti, Stefano; Cencini, Massimo; Vergni, Davide; Vulpiani, Angelo

2015-07-01

Understanding the conditions ensuring the persistence of a population is an issue of primary importance in population biology. The first theoretical approach to the problem dates back to the 1950s with the Kierstead, Slobodkin, and Skellam (KiSS) model, namely a continuous reaction-diffusion equation for a population growing on a patch of finite size L surrounded by a deadly environment with infinite mortality, i.e., an oasis in a desert. The main outcome of the model is that only patches above a critical size allow for population persistence. Here we introduce an individual-based analog of the KiSS model to investigate the effects of discreteness and demographic stochasticity. In particular, we study the average time to extinction both above and below the critical patch size of the continuous model and investigate the quasistationary distribution of the number of individuals for patch sizes above the critical threshold.

Ultra preconcentration of polycyclic aromatic hydrocarbons in smoked bacon by a combination of SPE and DLLME.

PubMed

Liu, Xiaofang; Zhou, Shu; Zhu, Quanfei; Ye, Yong; Chen, Huaixia

2014-09-01

A sample pretreatment method, solid-phase extraction combined with dispersive liquid-liquid microextraction (SPE-DLLME), was established for the sensitive determination of polycyclic aromatic hydrocarbons (PAHs) in smoked bacon samples. In the SPE-DLLME process, three PAHs including naphthalene (Naph), phenanthrene (Phen) and pyrene (Pyr) were extracted from samples and transferred into C18 SPE cartridge. The target analytes were subsequently eluted with 1.2 ml of acetonitrile-dichloromethane (5:1, v/v) mixture solution. The eluent was injected directly into the 5.0 ml ultrapure water in the subsequent DLLME procedure. The sedimented phase was concentrated under a gentle nitrogen flow to 120.0 µl. Finally, the analytes in the extraction solvent were determined by high-performance liquid chromatography with a ultra-violet detector. Some important extraction parameters affecting the performance, such as the sample solution flow rate, breakthrough volume, salt addition as well as the type and volume of the elution solvent were optimized. The developed method provided an ultra enrichment factors for PAHs ranged from 3478 to 3824. The method was applied for the selective extraction and sensitive determination of PAHs in smoked bacon samples. The limits of detection (S/N = 3) were 0.05, 0.01, 0.02 μg kg(-1) for Naph, Phen, Pyr, respectively. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

OASIS connections: results from an evaluation study.

PubMed

Czaja, Sara J; Lee, Chin Chin; Branham, Janice; Remis, Peggy

2012-10-01

The objectives of this study were to evaluate a community-based basic computer and Internet training program designed for older adults, provide recommendations for program refinement, and gather preliminary information on program sustainability. The program was developed by the OASIS Institute, a nonprofit agency serving older adults and implemented in 4 cities by community trainers across the United States. One hundred and ninety-six adults aged 40-90 years were assigned to the training or a wait-list control group. Knowledge of computers and the Internet, attitudes toward computers, and computer/Internet use were assessed at baseline, posttraining, and 3 months posttraining. The program was successful in increasing the computer/Internet skills of the trainees. The data indicated a significant increase in computer and Internet knowledge and comfort with computers among those who received the training. Further, those who completed the course reported an increase in both computer and Internet use 3 months posttraining. The findings indicate that a community-based computer and Internet training program delivered by community instructors can be effective in terms of increasing computer and Internet skills and comfort with computer technology among older adults.

Alto Patache fog oasis in the Atacama Desert: Geographical basis for a sustainable development program

NASA Astrophysics Data System (ADS)

Calderón, M.; Cereceda, P.; Larrain, H.; Osses, P.; Pérez, L.; Ibáñez, M.

2010-07-01

Alto Patache coastal fog oasis is a protected area located south of Iquique, Northern Chile, being presently in charge of the Atacama Desert Center (ADC) research group of the Pontificia Universidad Católica de Chile, since 1997. On 2007, the Chilean Government bestowed a piece of land stretch covering 1,114 hectares to ADC scientific group for scientific research, ecosystem protection and environmental education. This oasis has been recently studied from different points of view: climate, biogeography, fog collection, geomorphology, soil survey and land use planning, plant distribution, conservation and archaeology. During 2009, a study of the geographical basis to elaborate a general management plan was undertaken to collect information to fulfill our planned out objectives. Through this study, georreferenciated strategic information was compiled to evaluate future actions conducting to a sustainable development within the protected area. This information was translated into thematic maps showing the spatial distribution of variables like: climate, geology, geomorphology, soils, vegetation, fauna, archaeological sites and management zones. The methodology used is the analysis of satellite imagery, using GPS by creating a cartographic Data Base incorporated in GIS. Results show that the area starts at the littoral plain, ranging from 500 m to 2.000 m, being continued in parts by a piedmont intercepted by a very abrupt mega-cliff, or hectares of climbing sand dunes leading to a short high plateau limited by a soft hilly area to the East. Two soil types are characteristic: Entisols (Torriorthent) covering the coastal beach sediments, and Aridisols along the cliff and adjacent hills. Vegetation consists not only of a very rich lichen cover, but also of endangered vascular species associations constituting a very fragile sub-tropical coastal desert community, such as Eulychnia, Cumulopuntia, Eriosyce cacti, and Lycium - Nolana- Ephedra communities. Fog oasis

Coupling Hydrodynamic and Wave Propagation Codes for Modeling of Seismic Waves recorded at the SPE Test.

NASA Astrophysics Data System (ADS)

Larmat, C. S.; Rougier, E.; Delorey, A.; Steedman, D. W.; Bradley, C. R.

2016-12-01

The goal of the Source Physics Experiment (SPE) is to bring empirical and theoretical advances to the problem of detection and identification of underground nuclear explosions. For this, the SPE program includes a strong modeling effort based on first principles calculations with the challenge to capture both the source and near-source processes and those taking place later in time as seismic waves propagate within complex 3D geologic environments. In this paper, we report on results of modeling that uses hydrodynamic simulation codes (Abaqus and CASH) coupled with a 3D full waveform propagation code, SPECFEM3D. For modeling the near source region, we employ a fully-coupled Euler-Lagrange (CEL) modeling capability with a new continuum-based visco-plastic fracture model for simulation of damage processes, called AZ_Frac. These capabilities produce high-fidelity models of various factors believed to be key in the generation of seismic waves: the explosion dynamics, a weak grout-filled borehole, the surrounding jointed rock, and damage creation and deformations happening around the source and the free surface. SPECFEM3D, based on the Spectral Element Method (SEM) is a direct numerical method for full wave modeling with mathematical accuracy. The coupling interface consists of a series of grid points of the SEM mesh situated inside of the hydrodynamic code's domain. Displacement time series at these points are computed using output data from CASH or Abaqus (by interpolation if needed) and fed into the time marching scheme of SPECFEM3D. We will present validation tests with the Sharpe's model and comparisons of waveforms modeled with Rg waves (2-8Hz) that were recorded up to 2 km for SPE. We especially show effects of the local topography, velocity structure and spallation. Our models predict smaller amplitudes of Rg waves for the first five SPE shots compared to pure elastic models such as Denny &Johnson (1991).

A New Method of Facial Expression Recognition Based on SPE Plus SVM

NASA Astrophysics Data System (ADS)

Ying, Zilu; Huang, Mingwei; Wang, Zhen; Wang, Zhewei

A novel method of facial expression recognition (FER) is presented, which uses stochastic proximity embedding (SPE) for data dimension reduction, and support vector machine (SVM) for expression classification. The proposed algorithm is applied to Japanese Female Facial Expression (JAFFE) database for FER, better performance is obtained compared with some traditional algorithms, such as PCA and LDA etc.. The result have further proved the effectiveness of the proposed algorithm.

Larger benthic foraminiferal turnover across the Eocene-Oligocene transition at Siwa Oasis, Western Desert, Egypt

NASA Astrophysics Data System (ADS)

Orabi, H.; El Beshtawy, M.; Osman, R.; Gadallah, M.

2015-05-01

In the Eocene part of the Siwa Oasis, the larger foraminifera are represented by the genera Nummulites, Arxina, Operculina, Sphaerogypsina, Asterocyclina, Grzybowskia, Silvestriella, Gaziryina and Discocyclina in order of abundance. Operculina continues up to the early Oligocene as modern representatives in tropical regions, while the other genera became extinct. Nevertheless, the most common larger foraminiferal genus Lepidocyclina (Nephrolepidina) appears only in the lowermost Oligocene. In spite of the Eocene-Oligocene (E/O) transition is thought to have been attended by major continental cooling at northern middle and high latitudes, we discover that at the Siwa Oasis, there is a clear warming trend from the late Eocene (extinction level of Nummulites, Sphaerogypsina, Asterocyclina, Grzybowskia, Silvestriella and Discocyclina) to the early Oligocene is observed due to the high abundance of Operculina and occurrence of kaolinite and gypsiferous shale deposits in both Qatrani and El Qara formations (Oligocene) at this transition. The El Qara Formation is a new rock unit proposed herein for the Oligocene (Rupelian age) in the first time. Several episodes of volcanic activity occurred in Egypt during the Cenozoic. Mid Tertiary volcanicity was widespread and a number of successive volcanic pulses are starting in the late Eocene. The release of mantle CO2 from this very active volcanic episode may have in fact directly caused the warm Eocene-Oligocene greenhouse climate effect.

Comparison of the Microbial Diversity and Abundance Between the Freshwater Land-Locked Lakes of Schirmacher Oasis and the Perennially Ice-Covered Lake Untersee in East Antarctica

NASA Technical Reports Server (NTRS)

Huang, Jonathan; Hoover, Richard B.; Swain, Ashit; Murdock, Chris; Bej, Asim K.

2010-01-01

Extreme conditions such as low temperature, dryness, and constant UV-radiation in terrestrial Antarctica are limiting factors of the survival of microbial populations. The objective of this study was to investigate the microbial diversity and enumeration between the open water lakes of Schirmacher Oasis and the permanently ice-covered Lake Untersee. The lakes in Schirmacher Oasis possessed abundant and diverse group of microorganisms compared to the Lake Untersee. Furthermore, the microbial diversity between two lakes in Schirmacher Oasis (Lake L27C and L47) was compared by culture-based molecular approach. It was determined that L27Chad a richer microbial diversity representing 5 different phyla and 7 different genera. In contrast L47 consisted of 4 different phyla and 6 different genera. The difference in microbial community could be due to the wide range of pH between L27C (pH 9.1) and L47 (pH 5.7). Most of the microbes isolated from these lakes consisted of adaptive biological pigmentation. Characterization of the microbial community found in the freshwater lakes of East Antarctica is important because it gives a further glimpse into the adaptation and survival strategies found in extreme conditions.

Simultaneous analysis of multiple classes of antimicrobials in environmental water samples using SPE coupled with UHPLC-ESI-MS/MS and isotope dilution.

PubMed

Tran, Ngoc Han; Chen, Hongjie; Do, Thanh Van; Reinhard, Martin; Ngo, Huu Hao; He, Yiliang; Gin, Karina Yew-Hoong

2016-10-01

A robust and sensitive analytical method was developed for the simultaneous analysis of 21 target antimicrobials in different environmental water samples. Both single SPE and tandem SPE cartridge systems were investigated to simultaneously extract multiple classes of antimicrobials. Experimental results showed that good extraction efficiencies (84.5-105.6%) were observed for the vast majority of the target analytes when extraction was performed using the tandem SPE cartridge (SB+HR-X) system under an extraction pH of 3.0. HPLC-MS/MS parameters were optimized for simultaneous analysis of all the target analytes in a single injection. Quantification of target antimicrobials in water samples was accomplished using 15 isotopically labeled internal standards (ILISs), which allowed the efficient compensation of the losses of target analytes during sample preparation and correction of matrix effects during UHPLC-MS/MS as well as instrument fluctuations in MS/MS signal intensity. Method quantification limit (MQL) for most target analytes based on SPE was below 5ng/L for surface waters, 10ng/L for treated wastewater effluents, and 15ng/L for raw wastewater. The method was successfully applied to detect and quantify the occurrence of the target analytes in raw influent, treated effluent and surface water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Human settlement and its influencing factors during the historicalperiod in an oasis-desert transition zone of Dunhuang, Hexi Corridor,northwest China

NASA Astrophysics Data System (ADS)

Li, H.; Dong, G.; Zhang, S.

2017-12-01

Many ancient cities and settlement sites have been found in Lucaogou, an ancient oasis near Dunhuangcity in northwest China. These settlements indicate that humans inhabited this area during the historicalperiod. However, the chronology and subsistence practices of this area remain unclear. Based on newdata from radiocarbon dating, macrobotanical analysis, and the synthesis of historical documents andhigh-resolution paleoclimatic records, we discuss the inter-relationship between human settlements andplant resource utilization strategies at Lucaogou ancient oasis during historical period. Our resultsindicate that these ancient sites in Lucaogou area were built between the Han dynasty (202 BC-AD 220)and the Ming dynasty (AD 1368-AD 1644). People mainly used foxtail millet, broomcorn millet, barleyand three types of wood (Tamarix, Salix, Populus), probably as fuel for cooking. Human settlement intensityin the area during the historical period was primarily influenced by political situations, whichmight also have been affected by fluctuations in precipitation.

Locating S-wave sources for the SPE-5 explosion using time reversal methods and a close-in, 1000 sensor network

NASA Astrophysics Data System (ADS)

Myers, S. C.; Pitarka, A.; Mellors, R. J.

2016-12-01

The Source Physics Experiment (SPE) is producing new data to study the generation of seismic waves from explosive sources. Preliminary results show that far-field S-waves are generated both within the non-elastic volume surrounding explosive sources and by P- to S-wave scattering. The relative contribution of non-elastic phenomenology and elastic-wave scattering to far-field S-waves has been debated for decades, and numerical simulations based on the SPE experiments are addressing this question. The match between observed and simulated data degrades with event-station distance and with increasing time in each seismogram. This suggests that a more accurate model of subsurface elastic properties could result in better agreement between observed and simulated seismograms. A detailed model of subsurface structure has been developed using geologic maps and the extensive database of borehole logs, but uncertainty in structural details remains high. The large N instrument deployment during the SPE-5 experiment offers an opportunity to use time-reversal techniques to back project the wave field into the subsurface to locate significant sources of scattered energy. The large N deployment was nominally 1000, 5 Hz sensors (500 Z and 500 3C geophones) deployed in a roughly rectangular array to the south and east of the SPE-5 shot. Sensor spacing was nominally 50 meters in the interior portion of the array and 100 meters in the outer region, with two dense lines at 25 m spacing. The array covers the major geologic boundary between the Yucca Flat basin and the granitic Climax Stock in which the SPE experiments have been conducted. Improved mapping of subsurface scatterers is expected to result in better agreement between simulated and observed seismograms and aid in our understanding of S-wave generation from explosions. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.

Method of making MEA for PEM/SPE fuel cell

DOEpatents

Hulett, Jay S.

2000-01-01

A method of making a membrane-electrode-assembly (MEA) for a PEM/SPE fuel cell comprising applying a slurry of electrode-forming material directly onto a membrane-electrolyte film. The slurry comprises a liquid vehicle carrying catalyst particles and a binder for the catalyst particles. The membrane-electrolyte is preswollen by contact with the vehicle before the electrode-forming slurry is applied to the membrane-electrolyte. The swollen membrane-electrolyte is constrained against shrinking in the "x" and "y" directions during drying. Following assembly of the fuel cell, the MEA is rehydrated inside the fuel cell such that it swells in the "z" direction for enhanced electrical contact with contiguous electrically conductive components of the fuel cell.

Assessing the changes in land use and ecosystem services in an oasis agricultural region of Yanqi Basin, Northwest China.

PubMed

Wang, Shuixian; Wu, Bin; Yang, Pengnian

2014-12-01

The Yanqi Basin, one of the most productive agricultural areas, has a high population density in Xinjiang, Northwest China. Land use changes, mainly driven by oasis expansion, significantly impact ecosystem services and functions, but these effects are difficult to quantify. The valuation of ecosystem services is important to clarify the ecological and environmental changes caused by agriculturalization of oasis. This study aimed to investigate variations in ecosystem services in response to land use changes during oasis agricultural expansion activities in the Yanqi Basin from 1964 to 2009. The methods used were based on formula of ecosystem service value (ESV) and ESV coefficients. Satellite data were combined with the ESV coefficients to quantify land use changes and ecosystem service changes in the study area. Sensitivity analysis determined the effect of manipulating the coefficients on the estimated values. The results show that the total ESVs in the Yanqi Basin were $1,674, $1,692, $1,471, $1,732, and $1,603 million in 1964, 1973, 1989, 1999, and 2009, respectively. The net deline in ESV was $71 million in the past 46 years, but the ESVs of each types of landscape changed significantly. The aggregated ESVs of water areas and wetlands were approximately 80 % of the total ESV. Water supply and waste treatment were the two largest service functions and contributed approximately 65 % of the total ESV. The estimated ESVs in this study were elastic with respect to the value coefficients. Therefore, the estimations were robust in spite of uncertainties on the value coefficients. These significant changes in land use occur within the entire basin over the study period. These changes cause environmental problems, such as land degradation, vegetation degeneracy, and changes in aquatic environment.

Sedimentology of the fluvial and fluvio-marine facies of the Bahariya Formation (Early Cenomanian), Bahariya Oasis, Western Desert, Egypt

NASA Astrophysics Data System (ADS)

Khalifa, M. A.; Catuneanu, O.

2008-05-01

The Lower Cenomanian Bahariya Formation in the Bahariya Oasis, Western Desert, Egypt, was deposited under two coeval environmental conditions. A fully fluvial system occurs in the southern portion of the Bahariya Oasis, including depositional products of meandering and braided streams, and a coeval fluvio-marine setting is dominant to the north. These deposits are organized into four unconformity-bounded depositional sequences, whose architecture is shaped by a complex system of incised valleys. The fluvial portion of the lower two depositional sequences is dominated by low-energy, meandering systems with a tabular geometry, dominated by overbank facies. The fluvial deposits of the upper two sequences represent the product of sedimentation within braided streams, and consist mainly of amalgamated channel-fills. The braided fluvial systems form the fill of incised valleys whose orientation follows a southeast-northwest trending direction, and which truncate the underlying sequences. Four sedimentary facies have been identified within the braided-channel systems, namely thin-laminated sandstones (Sh), cross-bedded sandstones (Sp, St), massive ferruginous sandstones (Sm) and variegated mudstones (Fm). The exposed off-channel overbank facies of the meandering systems include floodplain (Fm) and crevasse splay (Sl) facies. The fluvio-marine depositional systems consist of interbedded floodplain, coastal and shallow-marine deposits. The floodplain facies include fine-grained sandstones (Sf), laminated siltstones (Stf) and mudstones (Mf) that show fining-upward cycles. The coastal to shallow-marine facies consist primarily of mudstones (Mc) and glauconitic sandstones (Gc) organized vertically in coarsening-upward prograding cyclothems topped by thin crusts of ferricrete (Fc). The four depositional sequences are present across the Bahariya Oasis, albeit with varying degrees of preservation related to post-depositional erosion associated with the formation of sequence

Molecularly imprinted phloroglucinol-formaldehyde-melamine resin prepared in a deep eutectic solvent for selective recognition of clorprenaline and bambuterol in urine.

PubMed

Liang, Shiru; Yan, Hongyuan; Cao, Jiankun; Han, Yehong; Shen, Shigang; Bai, Ligai

2017-01-25

A new molecularly imprinted phloroglucinol-formaldehyde-melamine resin (MIPFMR) was synthesized in a deep eutectic solvent (DES) using phenylephrine as a dummy template. The MIPFMR was used as a solid phase extraction (SPE) sorbent for the selective isolation and recognition of clorprenaline (CLP) and bambuterol (BAM) in urine. Phloroglucinol and melamine were used as double functional monomers that introduced abundant hydrophilic groups (such as hydroxyl groups, imino groups, and ether linkages) into the MIPFMR, making it compatible with aqueous solvents. In addition, the formation of DES by combining the quaternary ammonium salt of choline chloride with ethylene glycol as a hydrogen bond donor was an environmentally safe alternative to toxic organic solvents such as chloroform and dimethylsulfoxide that are typically used in the preparation of most molecularly imprinted polymers (MIPs). Moreover, MIPFMR-based SPE of CLP and BAM in urine resulted in higher recoveries and purer extracts than those obtained by using other SPE materials (e.g., SCX, C 18 , HLB, and non-imprinted phloroglucinol-formaldehyde-melamine resin (NIPFMR)). The optimized MIPFMR-SPE-HPLC-UV method had good linearity (r 2  ≥ 0.9996) ranging from 15.0 to 3000.0 ng mL -1 for CLP and BAM, and the recoveries at three spiked levels ranged from 91.7% to 100.1% with RSDs ≤7.6%. The novel MIPFMR-SPE-HPLC-UV method is simple, selective, and accurate, and can be used for the determination of CLP and BAM in urine samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of Colorimetric Solid Phase Extraction (C-SPE) to Monitoring Nickel(II) and Lead(II) in Spacecraft Water Supplies

NASA Technical Reports Server (NTRS)

Diaz, Neil C.; Gazda, Daniel B.; Fritz, James S.; Porter, Marc D.; Rutz, Jeff; Mudgett, Paul; Schultz, John

2004-01-01

Archived water samples collected on the International Space Station (ISS) and returned to Earth for analysis have, in a few instances, contained trace levels of heavy metals. Building on our previous advances using Colorimetric Solid Phase Extraction (C-SPE) as a biocide monitoring technique, we are devising methods for the low level monitoring of nickel(II), lead(II) and other heavy metals. C-SPE is a sorption-spectrophotometric platform based on the extraction of analytes onto a membrane impregnated with a colorimetric reagent that are then quantified on the surface of the membrane using a diffuse reflectance spectrophotometer. Along these lines, we have determined nickel(II) via complexation with dimethylglyoxime (DMG) and begun to examine the analysis of lead(II) by its reaction with 2,5- dimercapto-1,3,4-thiadiazole (DMTD) and 4-(2- pyridylazo)-resorcinol (PAR). These developments are also extending a new variant of C-SPE in which immobilized reagents are being incorporated into this methodology in order to optimize sample reaction conditions and to introduce the colorimetric reagent. This paper describes the status of our development of these two new methods.

Ultrahigh and High Resolution Structures and Mutational Analysis of Monomeric Streptococcus pyogenes SpeB Reveal a Functional Role for the Glycine-rich C-terminal Loop

DOE Office of Scientific and Technical Information (OSTI.GOV)

González-Páez, Gonzalo E.; Wolan, Dennis W.

2012-09-05

Cysteine protease SpeB is secreted from Streptococcus pyogenes and has been studied as a potential virulence factor since its identification almost 70 years ago. Here, we report the crystal structures of apo mature SpeB to 1.06 {angstrom} resolution as well as complexes with the general cysteine protease inhibitor trans-epoxysuccinyl-L-leucylamido(4-guanidino)butane and a novel substrate mimetic peptide inhibitor. These structures uncover conformational changes associated with maturation of SpeB from the inactive zymogen to its active form and identify the residues required for substrate binding. With the use of a newly developed fluorogenic tripeptide substrate to measure SpeB activity, we determined IC{sub 50}more » values for trans-epoxysuccinyl-L-leucylamido(4-guanidino)butane and our new peptide inhibitor and the effects of mutations within the C-terminal active site loop. The structures and mutational analysis suggest that the conformational movements of the glycine-rich C-terminal loop are important for the recognition and recruitment of biological substrates and release of hydrolyzed products.« less

Proved reserves definitions proposed for adoption by SPE, AAPG, and API

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1980-09-01

A joint-association committee was organized to write a unified set of definitions for proved reserves that SPE, AAPG, API, other interested organizations, industry and units of government can adopt and use. The proposed definitions appear for the purpose of soliciting member comments before their anticipated adoption by the 3 sponsoring organizations. The committee directed its carefully written proposed definitions toward all present and future applications in industry and government circles. These definitions include the terms proved reserves, crude oil, natural gas, natural gas liquids, reservoir, and enhanced recovery.

Levels of perfluorinated compounds in human breast milk in Jordan: the impact of sociodemographic characteristics.

PubMed

Al-sheyab, Nihaya A; Al-Qudah, Khaled M; Tahboub, Yahya R

2015-08-01

There is scarcity in literature in regards to the exact levels of such compounds in the Middle Eastern region including Jordan. This study was conducted to measure the presence and levels of perfluoroalkyl substances (PFASs) (perfluoroocane sulfonate (PFOS) and perfluorooctanoic acid (PFOA)) in human milk and local fresh cow milk in northern Jordan and also to investigate the relationship between levels of PFASs and some sociodemographic characteristics of breastfeeding mothers and their infants as well as usage of Teflon kitchenware products. Seventy-nine milk samples were collected from breastfeeding women and 25 samples from local fresh cow milk in northern Jordan. Levels of PFOS and PFOA were liquid/liquid extracted (LLE) by acetone followed by purification on an Oasis hydrophilic-lipophilic balance (HLB) solid-phase extraction (SPE). Separations and detections were performed by liquid chromatography-tandem mass spectrometry. Limits of quantitation (LOQs) were 10 ng/L for both PFOA and PFOS. The measured concentrations ranged between non-detectable (ND) and 178 ng/L for PFOS and between 24 and 1120 ng/L for PFOA in human milk and between ND-178 ng/L and LOQ-160 ng/L in fresh cow milk, respectively. Median concentrations of PFOS in human milk samples from Jordan in this study were lower than those found in a recent study from Italy. Moreover, mean concentrations of PFOA and PFOS were significantly higher in milk samples provided by older women. Also, mean concentrations of PFOA was much higher in multiparas and those who have younger infants. The mean rank of PFOA was twice as high in the milk of women who had older Teflon products in kitchen compared to those who had relatively new Teflon products.

Evaluation of SPE and GCR Radiation Effects in Inflatable, Space Suit and Composite Habitat Materials Project

NASA Technical Reports Server (NTRS)

Waller, Jess M.; Nichols, Charles

2016-01-01

The radiation resistance of polymeric and composite materials to space radiation is currently based on irradiating materials with Co-60 gamma-radiation to the equivalent total ionizing dose (TID) expected during mission. This is an approximation since gamma-radiation is not truly representative of the particle species; namely, Solar Particle Event (SPE) protons and Galactic Cosmic Ray (GCR) nucleons, encountered in space. In general, the SPE and GCR particle energies are much higher than Co-60 gamma-ray photons, and since the particles have mass, there is a displacement effect due to nuclear collisions between the particle species and the target material. This effort specifically bridges the gap between estimated service lifetimes based on decades old Co-60 gamma-radiation data, and newer assessments of what the service lifetimes actually are based on irradiation with particle species that are more representative of the space radiation environment.

Recent improvements in SPE3D: a VR-based surgery planning environment

NASA Astrophysics Data System (ADS)

Witkowski, Marcin; Sitnik, Robert; Verdonschot, Nico

2014-02-01

SPE3D is a surgery planning environment developed within TLEMsafe project [1] (funded by the European Commission FP7). It enables the operator to plan a surgical procedure on the customized musculoskeletal (MS) model of the patient's lower limbs, send the modified model to the biomechanical analysis module, and export the scenario's parameters to the surgical navigation system. The personalized patient-specific three-dimensional (3-D) MS model is registered with 3-D MRI dataset of lower limbs and the two modalities may be visualized simultaneously. Apart from main planes, any arbitrary MRI cross-section can be rendered on the 3-D MS model in real time. The interface provides tools for: bone cutting, manipulating and removal, repositioning muscle insertion points, modifying muscle force, removing muscles and placing implants stored in the implant library. SPE3D supports stereoscopic viewing as well as natural inspection/manipulation with use of haptic devices. Alternatively, it may be controlled with use of a standard computer keyboard, mouse and 2D display or a touch screen (e.g. in an operating room). The interface may be utilized in two main fields. Experienced surgeons may use it to simulate their operative plans and prepare input data for a surgical navigation system while student or novice surgeons can use it for training.

CORRTEX Diagnostic Deployment for the SPE-III experiment, 24 July 2012: Fielding Report and Preliminary Data Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandoval, Thomas D.; Schultz-Fellenz, Emily S.

2012-08-29

The Continuous Reflectometry for Radius vs Time Experiments (CORRTEX) diagnostic system was deployed for the third explosives test in the Source Physics Experiment (SPE) sequence to monitor and verify several conditions of the experiment including the detonation velocity of the explosive package and functioning of explosive initiators. Six distance-marked coaxial cables were installed on the SPE-III explosives canister, and key locations documented through along-cable length measurements and photography. CORRTEX uses electrical-pulse time-domain reflectometry to continuously record the two-way transit time (TWTT) of the cables. As the shock front of the detonation advances, the coaxial cable is shorted or destroyed, andmore » the resulting TWTT also decreases. Interpretation of these changes as a function of TWTT can be converted to positional measurements using known parameters of the cables.« less

Solid-phase extraction and purification of membrane proteins using a UV-modified PMMA microfluidic bioaffinity μSPE device.

PubMed

Battle, Katrina N; Jackson, Joshua M; Witek, Małgorzata A; Hupert, Mateusz L; Hunsucker, Sally A; Armistead, Paul M; Soper, Steven A

2014-03-21

We present a novel microfluidic solid-phase extraction (μSPE) device for the affinity enrichment of biotinylated membrane proteins from whole cell lysates. The device offers features that address challenges currently associated with the extraction and purification of membrane proteins from whole cell lysates, including the ability to release the enriched membrane protein fraction from the extraction surface so that they are available for downstream processing. The extraction bed was fabricated in PMMA using hot embossing and was comprised of 3600 micropillars. Activation of the PMMA micropillars by UV/O3 treatment permitted generation of surface-confined carboxylic acid groups and the covalent attachment of NeutrAvidin onto the μSPE device surfaces, which was used to affinity select biotinylated MCF-7 membrane proteins directly from whole cell lysates. The inclusion of a disulfide linker within the biotin moiety permitted release of the isolated membrane proteins via DTT incubation. Very low levels (∼20 fmol) of membrane proteins could be isolated and recovered with ∼89% efficiency with a bed capacity of 1.7 pmol. Western blotting indicated no traces of cytosolic proteins in the membrane protein fraction as compared to significant contamination using a commercial detergent-based method. We highlight future avenues for enhanced extraction efficiency and increased dynamic range of the μSPE device using computational simulations of different micropillar geometries to guide future device designs.

Development and optimization of the determination of pharmaceuticals in water samples by SPE and HPLC with diode-array detection.

PubMed

Pavlović, Dragana Mutavdžić; Ašperger, Danijela; Tolić, Dijana; Babić, Sandra

2013-09-01

This paper describes the development, optimization, and validation of a method for the determination of five pharmaceuticals from different therapeutic classes (antibiotics, anthelmintics, glucocorticoides) in water samples. Water samples were prepared using SPE and extracts were analyzed by HPLC with diode-array detection. The efficiency of 11 different SPE cartridges to extract the investigated compounds from water was tested in preliminary experiments. Then, the pH of the water sample, elution solvent, and sorbent mass were optimized. Except for optimization of the SPE procedure, selection of the optimal HPLC column with different stationary phases from different manufacturers has been performed. The developed method was validated using spring water samples spiked with appropriate concentrations of pharmaceuticals. Good linearity was obtained in the range of 2.4-200 μg/L, depending on the pharmaceutical with the correlation coefficients >0.9930 in all cases, except for ciprofloxacin (0.9866). Also, the method has revealed that low LODs (0.7-3.9 μg/L), good precision (intra- and interday) with RSD below 17% and recoveries above 98% for all pharmaceuticals. The method has been successfully applied to the analysis of production wastewater samples from the pharmaceutical industry. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Characteristics of four SPE groups with different origins and acceleration processes

NASA Astrophysics Data System (ADS)

Kim, R.-S.; Cho, K.-S.; Lee, J.; Bong, S.-C.; Joshi, A. D.; Park, Y.-D.

2015-09-01

Solar proton events (SPEs) can be categorized into four groups based on their associations with flare or CME inferred from onset timings as well as acceleration patterns using multienergy observations. In this study, we have investigated whether there are any typical characteristics of associated events and acceleration sites in each group using 42 SPEs from 1997 to 2012. We find the following: (i) if the proton acceleration starts from a lower energy, a SPE has a higher chance to be a strong event (> 5000 particle flux per unit (pfu)) even if its associated flare and/or CME are not so strong. The only difference between the SPEs associated with flare and CME is the location of the acceleration site. (ii) For the former (Group A), the sites are very low (˜ 1 Rs) and close to the western limb, while the latter (Group C) have relatively higher (mean = 6.05 Rs) and wider acceleration sites. (iii) When the proton acceleration starts from the higher energy (Group B), a SPE tends to be a relatively weak event (< 1000 pfu), although its associated CME is relatively stronger than previous groups. (iv) The SPEs categorized by the simultaneous acceleration in whole energy range within 10 min (Group D) tend to show the weakest proton flux (mean = 327 pfu) in spite of strong associated eruptions. Based on those results, we suggest that the different characteristics of SPEs are mainly due to the different conditions of magnetic connectivity and particle density, which are changed with longitude and height as well as their origin.

Large-N Over the Source Physics Experiment (SPE) Phase I and Phase II Test Beds

NASA Astrophysics Data System (ADS)

Snelson, C. M.; Carmichael, J. D.; Mellors, R. J.; Abbott, R. E.

2014-12-01

One of the current challenges in the field of monitoring and verification is source discrimination of low-yield nuclear explosions from background seismicity, both natural and anthropogenic. Work is underway at the Nevada National Security Site to conduct a series of chemical explosion experiments using a multi-institutional, multi-disciplinary approach. The goal of this series of experiments, called the Source Physics Experiments (SPE), is to refine the understanding of the effect of earth structures on source phenomenology and energy partitioning in the source region, the transition of seismic energy from the near field to the far field, and the development of S waves observed in the far field. To fully explore these problems, the SPE series includes tests in both hard and soft rock geologic environments. The project comprises a number of activities, which range from characterizing the shallow subsurface to acquiring new explosion data from both the near field (<100 m) and the far field (>100 m). SPE includes a series of planned explosions (with different yields and depths of burials), which are conducted in the same hole and monitored by a diverse set of sensors recording characteristics of the explosions, ground-shock, seismo-acoustic energy propagation. This presentation focuses on imaging the full 3D wavefield over hard rock and soft rock test beds using a large number of seismic sensors. This overview presents statistical analyses of optimal sensor layout required to estimate wavefield discriminants and the planned deployment for the upcoming experiments. This work was conducted under Contract No. DE-AC52-06NA25946 with the U.S. Department of Energy. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Preconcentration of β-blockers using functionalized ordered mesoporous silica as sorbent for SPE and their determination in waters by chiral CE.

PubMed

Silva, Mariana; Morante-Zarcero, Sonia; Pérez-Quintanilla, Damián; Marina, María Luisa; Sierra, Isabel

2017-08-01

A method for simultaneous separation and determination of four enantiomeric pairs of β-blockers in waters by chiral CE has been developed. Off-line SPE was employed using functionalized ordered mesoporous silica as sorbent. Separation by CE was achieved using a BGE composed by methylated-β-CD (1.25% w/v) dissolved in a 50 mM phosphate buffer (pH 2.5) and 30°C, with good chiral resolution for all enantiomers. Mesoporous silica functionalized with octadecyl groups (denoted SBA15-C18) was prepared by a postsynthesis method and applied for the preconcentration of atenolol, propranolol, metoprolol, and pindolol enantiomers in waters by off-line SPE. Under optimized conditions, a preconcentration factor of 300 was achieved, employing 100 mg of SBA15-C18 as sorbent, with recoveries between 96 and 105% in tap water and good repeatability (% RSD = 7-11%, n = 6). Commercial C18 amorphous silica (ExtraBond R C 18 ) was also tested as sorbent for SPE, but results revealed better extraction capacity with higher recoveries for the SBA15-C18 material. The analytical characteristics of the off-line SPE-chiral CE method were evaluated, showing good precision, linearity, and accuracy with method quantification limits between 5.3 and 13.7 μg/L for all enantiomers. The SBA15-C18 material allowed the extraction of four enantiomeric pairs of β-blockers spiked in tap water, river water, and ground water with recoveries between 58 and 105%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Oasis impact structure, Libya: geological characteristics from ALOS PALSAR-2 data interpretation

NASA Astrophysics Data System (ADS)

van Gasselt, Stephan; Kim, Jung Rack; Choi, Yun-Soo; Kim, Jaemyeong

2017-02-01

Optical and infrared remote sensing may provide first-order clues for the identification of potential impact structures on the Earth. Despite the free availability of at least optical image data at highest resolution, research has shown that remote sensing analysis always remains inconclusive and extensive groundwork is needed for the confirmation of the impact origin of such structures. Commonly, optical image data and digital terrain models have been employed mainly for such remote sensing studies of impact structures. With the advent of imaging radar data, a few excursions have been made to also employ radar datasets. Despite its long use, capabilities of imaging radar for studying surface and subsurface structures have not been exploited quantitatively when applied for the identification and description of such features due to the inherent complexity of backscatter processes. In this work, we make use of higher-level derived radar datasets in order to gain clearer qualitative insights that help to describe and identify potential impact structures. We make use of high-resolution data products from the ALOS PALSAR-1 and ALOS PALSAR-2 L-band sensors to describe the heavily eroded Oasis impact structure located in the Libyan Desert. While amplitude radar data with single polarization have usually been utilized to accompany the suite of remote sensing datasets when interpreting impact structures in the past, we conclude that the integration of amplitude data with HH/HV/HH-HV polarization modes in standard and, in particular, in Ultra-Fine mode, as well as entropy-alpha decomposition data, significantly helps to identify and discriminate surface units based on their consolidation. Based on the overarching structural pattern, we determined the diameter of the eroded Oasis structure at 15.6 ± 0.5 km.

Real-Time Data Management, IP Telemetry, Data Integration, and Data Center Operations for the Source Physics Experiment (SPE), Nevada National Security Site

NASA Astrophysics Data System (ADS)

Plank, G.; Slater, D.; Torrisi, J.; Presser, R.; Williams, M.; Smith, K. D.

2012-12-01

The Nevada Seismological Laboratory (NSL) manages time-series data and high-throughput IP telemetry for the National Center for Nuclear Security (NCNS) Source Physics Experiment (SPE), underway on the Nevada National Security Site (NNSS). During active-source experiments, SPE's heterogeneous systems record over 350 channels of a variety of data types including seismic, infrasound, acoustic, and electro-magnetic. During the interim periods, broadband and short period instruments record approximately 200 channels of continuous, high-sample-rate seismic data. Frequent changes in sensor and station configurations create a challenging meta-data environment. Meta-data account for complete operational histories, including sensor types, serial numbers, gains, sample rates, orientations, instrument responses, data-logger types etc. To date, these catalogue 217 stations, over 40 different sensor types, and over 1000 unique recording configurations (epochs). Facilities for processing, backup, and distribution of time-series data currently span four Linux servers, 60Tb of disk capacity, and two data centers. Bandwidth, physical security, and redundant power and cooling systems for acquisition, processing, and backup servers are provided by NSL's Reno data center. The Nevada System of Higher Education (NSHE) System Computer Services (SCS) in Las Vegas provides similar facilities for the distribution server. NSL staff handle setup, maintenance, and security of all data management systems. SPE PIs have remote access to meta-data, raw data, and CSS3.0 compilations, via SSL-based transfers such as rsync or secure-copy, as well as shell access for data browsing and limited processing. Meta-data are continuously updated and posted on the Las Vegas distribution server as station histories are better understood and errors are corrected. Raw time series and refined CSS3.0 data compilations with standardized formats are transferred to the Las Vegas data server as available. For better

Why transition risk to psychosis is not declining at the OASIS ultra high risk service: The hidden role of stable pretest risk enrichment.

PubMed

Fusar-Poli, P; Palombini, E; Davies, C; Oliver, D; Bonoldi, I; Ramella-Cravaro, V; McGuire, P

2018-02-01

The reason for declining risk to psychosis across individuals assessed and meeting Ultra High Risk (UHR) criteria is still unclear. No studies have investigated the potential substantial role of the underlying risk enrichment across all the individuals undergoing an UHR assessment. Cohort study including all non-psychotic subjects who were assessed on suspicion of psychosis risk by the OASIS UHR service in the period 2001 to 2015. Posttest (after UHR assessment) and pretest risk (before UHR assessment) of psychosis were stratified and compared across three time periods (2001-2005, 2006-2010, 2011-2015) with Cox analysis and modulating factors were investigated. The posttest risk of psychosis at the OASIS service has increased from the initial pilot years of the service (2001-2005) and then stabilised and not declined over the following decade (2006-2010 and 2011-2015). This was paralleled by a similar course of pretest risk for psychosis. Stability of pretest risk for psychosis over the past decade was associated with a lack of change in ethnicity and to counterweighting changes in the type of referral sources over different time periods. The time course of transition risk to psychosis in UHR services is strictly associated with the time course of pretest risk enrichment. If the latter remains stable over time, as for the OASIS service, no declining transition risk is observed over the most recent years. Pretest risk enrichment is determined by recruitment and sampling strategies. This study confirms the need to control these factors in the UHR field. Copyright © 2017 Elsevier B.V. All rights reserved.

Stability of pharmaceuticals and other polar organic compounds stored on polar organic chemical integrative samplers and solid-phase extraction cartridges.

PubMed

Carlson, Jules C; Challis, Jonathan K; Hanson, Mark L; Wong, Charles S

2013-02-01

The stability of 24 chemicals, including pharmaceuticals and personal care products, and some agrochemicals on extraction media was evaluated by preloading them onto Oasis hydrophilic lipophilic balanced solid-phase extraction (SPE) cartridges and polar organic chemical integrative samplers (POCIS) followed by storage at -20°C over time. After 20 months, the average loss was 11% on POCIS, with only 2,4-dichlorophenoxyacetic acid, atrazine, chlorpyrifos, and gemfibrozil showing a statistically significant decline compared with initial concentrations. Losses on SPE cartridges were below 19%, with an average loss of 9%. In addition to laboratory spiked samples, multiple POCIS deployed in wastewater-impacted surface waters and SPE extracts of these waters were stored in their original coextracted matrix for nearly two years with minimal observed losses. Errors from typical sampling, handling, and concentration estimates from POCIS sampling rates were typically ± 15 to 30% relative standard deviation, so observed storage losses are minimal for most POCIS applications. While losses during storage on SPE cartridges for 20 months were small but statistically significant for many compounds, addition of labeled internal standards prior to freezing should correct for such losses. Thus, storage of processed water samples for analysis of polar organic pollutants is viable for archival purposes or studies for which samples cannot be analyzed in the short term. Copyright © 2012 SETAC.

[Archaeal diversity in permafrost deposits of Bunger Hills Oasis and King George Island (Antarctica) according to the 16S rRNA gene sequencing].

PubMed

Karaevskaia, E S; Demchenko, L S; Demidov, N É; Rivkina, E M; Bulat, S A; Gilichinskiĭ, D A

2014-01-01

Archaeal communities of permafrost deposits of King George Island and Bunger Hills Oasis (Antarctica) differing in the content of biogenic methane were analyzed using clone libraries of two 16S rRNA gene regions. Phylotypes belonging to methanogenic archaea were identified in all horizons.

[Predicting gainful employment in a population sample of 4225 statutory pension insurance members covering a prognostic period of five years using a brief subjective prognostic employment scale (SPE Scale)].

PubMed

Mittag, O; Meyer, T; Glaser-Möller, N; Matthis, C; Raspe, H

2006-05-01

Vocational (dis-)ability is a key concept in social medicine. It plays a major role in the realm of statutory pension funds (e. g. appraisal of applications for early retirement) as well as in epidemiologic or rehabilitation research. In a former population-based survey reliability of a short scale assessing the subjective prognosis of gainful employment (SPE-Scale, range = 0 - 3) had been tested. We now wanted to explore whether the SPE-Scale allows a prediction of vocational outcomes (early retirement) in the population sample over longer periods of time. Statutory pension insurees from Luebeck and surroundings aged between 40 and 55 were surveyed by questionnaire in 1999/2000. For 4225 subjects (= 95% of the original cohort) we obtained the following outcome data from pension fund records: dates of any applications for early retirement and beginning of retirement, date of death. The follow-up period covers 4.75 years on average. During this period 323 applications for early retirement (= 7.6%) were filed, and 200 subjects (= 4.7%) actually retired. First analysis including age and sex as covariates showed a threefold (SPE = 2) and eightfold (SPE = 3) risk of early retirement. Multivariate analysis (covariates: overall health status, number of chronic conditions, approved disability, subjective vocational ability, and length of sick leave measured at study onset) yielded a twofold risk of filing an application for early retirement (SPE = 3). The SPE-Scale is an appropriate screening instrument for hazards regarding gainful employment. It also can be recommended for use in epidemiologic or rehabilitation surveys.

Determination of perfluorinated chemicals in food and drinking water using high-flow solid-phase extraction and ultra-high performance liquid chromatography/tandem mass spectrometry.

PubMed

Chang, Ying-Chia; Chen, Wen-Ling; Bai, Fang-Yu; Chen, Pau-Chung; Wang, Gen-Shuh; Chen, Chia-Yang

2012-01-01

For this study, we developed methods of determining ten perfluorinated chemicals in drinking water, milk, fish, beef, and pig liver using high-flow automated solid-phase extraction (SPE) and ultra-high performance liquid chromatography/tandem mass spectrometry. The analytes were separated on a core-shell Kinetex C18 column. The mobile phase was composed of methanol and 10-mM N-methylmorpholine. Milk was digested with 0.5 N potassium hydroxide in Milli-Q water, and was extracted with an Atlantic HLB disk to perform automated SPE at a flow rate ranged from 70 to 86 mL/min. Drinking water was directly extracted by the SPE. Solid food samples were digested in alkaline methanol and their supernatants were diluted and also processed by SPE. The disks were washed with 40% methanol/60% water and then eluted with 0.1% ammonium hydroxide in methanol. Suppression of signal intensity of most analytes by matrixes was lower than 50%; it was generally lower in fish and drinking water but higher in liver. Most quantitative biases and relative standard deviations were lower than 15%. The limits of detection for most analytes were sub-nanograms per liter for drinking water and sub-nanograms per gram for solid food samples. This method greatly shortened the time and labor needed for digestion, SPE, and liquid chromatography. This method has been applied to analyze 14 types of food samples. Perfluorooctanoic acid was found to be the highest among the analytes (median at 3.2-64 ng/g wet weight), followed by perfluorodecanoic acid (0.7-25 ng/g) and perfluorododecanoic acid (0.6-15 ng/g).

Crystal structure of the zymogen form of the group A Streptococcus virulence factor SpeB: an integrin-binding cysteine protease.

PubMed

Kagawa, T F; Cooney, J C; Baker, H M; McSweeney, S; Liu, M; Gubba, S; Musser, J M; Baker, E N

2000-02-29

Pathogenic bacteria secrete protein toxins that weaken or disable their host, and thereby act as virulence factors. We have determined the crystal structure of streptococcal pyrogenic exotoxin B (SpeB), a cysteine protease that is a major virulence factor of the human pathogen Streptococcus pyogenes and participates in invasive disease episodes, including necrotizing fasciitis. The structure, determined for the 40-kDa precursor form of SpeB at 1.6-A resolution, reveals that the protein is a distant homologue of the papain superfamily that includes the mammalian cathepsins B, K, L, and S. Despite negligible sequence identity, the protease portion has the canonical papain fold, albeit with major loop insertions and deletions. The catalytic site differs from most other cysteine proteases in that it lacks the Asn residue of the Cys-His-Asn triad. The prosegment has a unique fold and inactivation mechanism that involves displacement of the catalytically essential His residue by a loop inserted into the active site. The structure also reveals the surface location of an integrin-binding Arg-Gly-Asp (RGD) motif that is a feature unique to SpeB among cysteine proteases and is linked to the pathogenesis of the most invasive strains of S. pyogenes.

SURFEX v8.0 interface with OASIS3-MCT to couple atmosphere with hydrology, ocean, waves and sea-ice models, from coastal to global scales

NASA Astrophysics Data System (ADS)

Voldoire, Aurore; Decharme, Bertrand; Pianezze, Joris; Lebeaupin Brossier, Cindy; Sevault, Florence; Seyfried, Léo; Garnier, Valérie; Bielli, Soline; Valcke, Sophie; Alias, Antoinette; Accensi, Mickael; Ardhuin, Fabrice; Bouin, Marie-Noëlle; Ducrocq, Véronique; Faroux, Stéphanie; Giordani, Hervé; Léger, Fabien; Marsaleix, Patrick; Rainaud, Romain; Redelsperger, Jean-Luc; Richard, Evelyne; Riette, Sébastien

2017-11-01

This study presents the principles of the new coupling interface based on the SURFEX multi-surface model and the OASIS3-MCT coupler. As SURFEX can be plugged into several atmospheric models, it can be used in a wide range of applications, from global and regional coupled climate systems to high-resolution numerical weather prediction systems or very fine-scale models dedicated to process studies. The objective of this development is to build and share a common structure for the atmosphere-surface coupling of all these applications, involving on the one hand atmospheric models and on the other hand ocean, ice, hydrology, and wave models. The numerical and physical principles of SURFEX interface between the different component models are described, and the different coupled systems in which the SURFEX OASIS3-MCT-based coupling interface is already implemented are presented.

Micro-solid-phase extraction (µ-SPE) of organophosphorous pesticides from wheat followed by LC-MS/MS determination.

PubMed

Della Pelle, Flavio; Di Crescenzo, Maria Chiara; Sergi, Manuel; Montesano, Camilla; Di Ottavio, Francesca; Scarpone, Rossana; Scortichini, Giampiero; Compagnone, Dario

2016-01-01

A rapid, selective and effective method of extraction, clean-up and concentration of organophosphorous pesticides from wheat followed by electrospray (ESI) LC-MS/MS analysis was developed. The μ-SPE (micro-solid-phase extraction) procedure resulted in good analytical performance and reduced at the same time matrix effects, analysis time and solvent consumption. Limits of detection (LODs) and quantification (LOQs) were in the range of 0.3-10 and 1-30 μg kg(-1), respectively, with good reproducibility (RSD ≤ 13.8) and recoveries between 75% and 109%. Coefficients of determination (r(2)) were greater than 0.996 for the studied pesticides. Despite the reduced sorbent bed mass of μ-SPE tips (4.2 mg), the analytical data showed that no saturation phenomena occurs in the tested range of concentration both for single compounds and mixtures. Several real samples were analysed and the concentrations of the selected pesticides were found to be below the respective maximum residue limit (MRLs).

A sensitive analytical procedure for monitoring acrylamide in environmental water samples by offline SPE-UPLC/MS/MS.

PubMed

Togola, Anne; Coureau, Charlotte; Guezennec, Anne-Gwenaëlle; Touzé, Solène

2015-05-01

The presence of acrylamide in natural systems is of concern from both environmental and health points of view. We developed an accurate and robust analytical procedure (offline solid phase extraction combined with UPLC/MS/MS) with a limit of quantification (20 ng L(-1)) compatible with toxicity threshold values. The optimized (considering the nature of extraction phases, sampling volumes, and solvent of elution) solid phase extraction (SPE) was validated according to ISO Standard ISO/IEC 17025 on groundwater, surface water, and industrial process water samples. Acrylamide is highly polar, which induces a high variability during the SPE step, therefore requiring the use of C(13)-labeled acrylamide as an internal standard to guarantee the accuracy and robustness of the method (uncertainty about 25 % (k = 2) at limit of quantification level). The specificity of the method and the stability of acrylamide were studied for these environmental media, and it was shown that the method is suitable for measuring acrylamide in environmental studies.

Dynamic Conservation of Date Palms: The Future of a Genetic Resource at the Nexus of Climate Change, Desertification and Salinity Stress in Oasis Ecosystems

USDA-ARS?s Scientific Manuscript database

The date palm (Phoenix dactylifera) is the only indigenous, wild desert plant definitely domesticated in its native harsh environment, and along with the camel (Camelus dromedarius), was responsible for opening the vast desert territories for human activity and the development of oasis ecosystems, w...

Design and test status for life support applications of SPE oxygen generation systems. [Solid Polymer Electrolyte

NASA Technical Reports Server (NTRS)

Titterington, W. A.; Erickson, A. C.

1975-01-01

An advanced six-man rated oxygen generation system has been fabricated and tested as part of a NASA/JSC technology development program for a long lived, manned spacecraft life support system. Details of the design and tests results are presented. The system is based on the Solid Polymer Electrolyte (SPE) water electrolysis technology and its nominal operating conditions are 2760 kN/sq m (400 psia) and 355 K (180 F) with an electrolysis module current density capability up to 350 mA/sq cm (326 ASF). The system is centered on a 13-cell SPE water electrolysis module having a single cell active area of 214 sq cm (33 sq in) and it incorporates instrumentation and controls for single pushbutton automatic startup/shutdown, component fault detection and isolation, and self-contained sensors and controls for automatic safe emergency shutdown. The system has been tested in both the orbital cyclic and continuous mode of operation. Various parametric tests have been completed to define the system capability for potential application in spacecraft environmental systems.

Evaluation of evapotranspiration and deep percolation under mulched drip irrigation in an oasis of Tarim basin, China

NASA Astrophysics Data System (ADS)

Li, Xianwen; Jin, Menggui; Zhou, Nianqing; Huang, Jinou; Jiang, Simin; Telesphore, Habiyakare

2016-07-01

Mulched drip irrigation for cotton field is an effective measure for the utilization of saline water, and the regulation of soil water and salt. However, the reasonable methods for quantifying actual evapotranspiration (ET) and deep percolation of recharge to groundwater are still not very well understood, which restricts the accurate regulation of soil water and salt for cotton growth in oasis. In this paper, a set of experiments of mulched drip irrigation with brackish water were conducted in a typical arid region of Tarim basin in southern Xinjiang, China. The irrigation events were recorded, and ET and fluctuations of groundwater table were carefully measured for two consecutive irrigation periods of flowering and bolling stages. A group of upscaling conversion methods were used to quantify the ET, in which canopy structure was considered to estimate the transpiration from leaf scale to a unit of field scale. The groundwater table had a significant response to the irrigation events, thus the deep percolation was estimated using water-table fluctuation method (WTF). Results showed that during the two irrigation events of flowering and bolling stages, the total ET was 31.1 mm with the soil surface evaporation of only 0.4 mm. The total percolation of recharge to groundwater was 48.2 mm which contributed to the groundwater run-off of 22.1 mm. Transpiration of 30.7 mm accounted for 98.6% of the total ET of 31.1 mm and 34.3% of the irrigation water of 90.6 mm. Compared with transpiration, the deep percolation accounted for 53.2% of irrigation water, indicating a serious excessive irrigation that recharged to groundwater. Soil salt budget showed that the salt leached into groundwater was 1.56 times of the input from brackish irrigation water and fertilization during the two irrigation periods. Even for the irrigation practice with brackish water, the accumulated salt of soil profile could also be leached out under large amount of irrigation water (e.g. 90.6 mm for the

Molecularly imprinted solid-phase extraction for determination of tilmicosin in feed using high performance liquid chromatography.

PubMed

Zheng, Yaqiu; Liu, Yahong; Guo, Hongbin; He, Limin; Fang, Binghu; Zeng, Zhenling

2011-04-01

A simple, sensitive and reproducible molecularly imprinted solid-phase extraction (MISPE) coupled with high performance liquid chromatographic method was developed for monitoring tilmicosin in feeds. The polymers were prepared using tylosin as mimic template molecule, methacrylic acid as functional monomer and ethylene glycol dimethacrylate as cross-linking monomer, and chloroform as a solvent by bulk polymerization. Under the optimum MISPE conditions, the novel polymer sorbent can selectively extract and enrich tilmicosin from variety of feeds. The MISPE cartridge was better than non-imprinted, C(18) and HLB cartridges in terms of both recovery and precision. Mean recoveries of tilmicosin from five kinds of feeds spiked at 1, 10 and 50 mg kg(-1) ranged from 76.9% to 95.6%, with intra-day and inter-day relative standard deviation less than 7.6%. The linearity was ranged from 1.0 to 100 mg L(-1) for matrix standard solution (r=0.9990). The limit of detection was approximately 0.35 mg kg(-1) and the limit of quantification was approximately 0.98 mg kg(-1). There was cleaner chromatogram by using MISPE than C(18) and HLB SPE. Copyright © 2011 Elsevier B.V. All rights reserved.

Exploring health-related quality of life and social functioning in adolescents with inflammatory bowel diseases after attending camp oasis and participating in a Facebook group.

PubMed

Plevinsky, Jill M; Greenley, Rachel N

2014-09-01

Youth with inflammatory bowel diseases are at risk for impaired health-related quality of life (HRQoL) and problems with social functioning. This study examined the impact of attending Camp Oasis (a disease-specific weeklong camp experience) on the HRQoL and social functioning of youth with inflammatory bowel diseases. Additionally, the study collected pilot data on whether a postcamp Facebook group contributed to maintenance or enhancement of these factors. Twenty-one youth ages 14 to 17 years who attended Camp Oasis and were Facebook users participated. HRQoL and social functioning (i.e., social support and social connectedness) were assessed through validated youth-report questionnaires at precamp, postcamp, and post-Facebook group. The Facebook group was 8 weeks in duration and encouraged campers to continue interacting in a private, protected setting. Analyses of effect sizes (i.e., Cohen's d) indicated medium and statistically significant increases in HRQoL from precamp to postcamp (d = 0.40) and small increases in social functioning (d = 0.15-0.24). Additional improvements in social functioning were seen from postcamp to post-Facebook group (d = 0.21-0.32), and overall improvements were observed in all domains (d = 0.17-0.52). Findings replicated those of previous research in documenting the value of Camp Oasis on enhancing HRQoL. Both the camp experience and the Facebook group contributed to improvements in youth social functioning. Thus, supplementing the camp experience with membership in an online community may enhance social functioning in adolescents with inflammatory bowel diseases.

Nanosized IrO2 electrocatalysts for oxygen evolution reaction in an SPE electrolyzer

NASA Astrophysics Data System (ADS)

Cruz, J. C.; Baglio, V.; Siracusano, S.; Ornelas, R.; Ortiz-Frade, L.; Arriaga, L. G.; Antonucci, V.; Aricò, A. S.

2011-04-01

Nanosized IrO2 electrocatalysts ( d 7-9 nm) with specific surface area up to 100 m2 g-1 were synthesized and characterized for the oxygen evolution reaction in a solid polymer electrolyte (SPE) electrolyzer. The catalysts were prepared by a colloidal method in aqueous solution and a subsequent thermal treatment. An iridium hydroxide hydrate precursor was obtained at 100 °C, which was, successively, calcined at different temperatures from 200 to 500 °C. The physico-chemical characterization was carried out by X-ray diffraction (XRD), thermogravimetry-differential scanning calorimetry (TG-DSC) and transmission electron microscopy (TEM). IrO2 catalysts were sprayed onto a Nafion 115 membrane up to a loading of 3 mg cm-2. A Pt catalyst was used at the cathode compartment with a loading of 0.6 mg cm-2. The electrochemical activity for water electrolysis of the membrane-electrode assemblies (MEAs) was investigated in a single cell SPE electrolyzer by steady-state polarization curves, impedance spectroscopy and chrono-amperometric measurements. A maximum current density of 1.3 A cm-2 was obtained at 1.8 V and 80 °C for the IrO2 catalyst calcined at 400 °C for 1 h. A stable performance was recorded in single cell for this anode catalyst at 80 °C. The suitable catalytic activity and stability of the most performing catalyst were interpreted in terms of proper combination between nanostructure and suitable morphology.

Development of SPE for recovery of polysaccharides and its application to the determination of monosaccharides composition of the polysaccharide sample of a lactobacillus KLB 58.

PubMed

Baik, Yoon Suk; Cheong, Won Jo

2007-07-01

A new SPE cartridge has been prepared in this study to purify polysaccharides of high molecular weights. A porous nonpolar styrene-divinylbenzene copolymer phase (Hamilton PRP-1) was used to make the new cartridge. The cartridge was conditioned with methanol, water, and ACN in sequence, and the sample dissolved in a small amount of water was loaded. Impurities of low molecular weights were removed first by elution of 80:20 or 90:10 v/v% ACN/water, and polysaccharides were quantitatively recovered by elution of 50:50 v/v% ACN/water or pure water. The recovery of pure dextran 10000 was 90-95%. The SPE method was applied to purification of the polysaccharide sample of KLB58, a new lactobacillus discovered in Korea. The purified KLB 58 sample (weight recovery after SPE purification; 60%) was hydrolyzed for analysis of composition of monosaccharides. The hydrolysate was found to be composed primarily of fructose, glucose, galactose, rhamnose, mannose with small amounts of fucose and ribose.

Osteoarthritis of the knee and hip and activity: a systematic international review and synthesis (OASIS).

PubMed

Vignon, Eric; Valat, Jean-Pierre; Rossignol, Michel; Avouac, Bernard; Rozenberg, Sylvie; Thoumie, Philippe; Avouac, Jérôme; Nordin, Margareta; Hilliquin, Pascal

2006-07-01

The goal of this study was to determine which activities in four domains, daily life, exercises, sports and occupational activities, should be recommended, in favor or against, for the patient suffering from knee or hip OA. Scientific literature was searched in Medline, Embase and Cochrane databases for articles in French or English, reporting original data. The articles were evaluated with standardized epidemiological criteria. Seventy-two articles were retained. Recommendations were graded according to the level of scientific evidence (A high, B moderate, C clinical consensus) and were formulated for primary care. For activity of daily life (ADL), the OASIS group states with a moderate level of scientific evidence, that ADL are a risk factor for knee OA and that risk increases with intensity and duration of activity. The group concludes that healthy subjects as well as OA patients in general can pursue a high level of physical activity, provided the activity is not painful and does not predispose to trauma (grade B). Radiographic or clinical OA is not a contraindication to promoting activity in patients who have a sedentary lifestyle (grade C). For exercises and other structured activities pursued with a goal of health improvement, the group states with a high level of scientific evidence that they have a favourable effect on pain and function in the sedentary knee OA patient. The OASIS group recommends the practice of exercises and other structured activities for the sedentary patient with knee OA (grade A). Static exercises are not favored over dynamic exercises, availability, preference and tolerance being the criteria for the choice of an exercise (grade A). As results deteriorate when exercises are stopped, they should be performed at a frequency of between one and three times per week (grade B). Professional assistance can be useful in improving initial compliance and perseverance (grade B). There is no scientific argument to support halting exercise in

The Climate and its Impacts on deterioration and weathering rate of EI-Nadura Temple in El- Kharga Oasis, Western Desert of Egypt.

NASA Astrophysics Data System (ADS)

Ismael, Hossam

2015-04-01

Undoubtedly, El-Kharga Oasis monumental sites are considered an important part of our world's cultural heritage in the South Western Desert of Egypt. These sites are scattered on the floor of the oasis representing ancient civilizations. The Roman stone monuments in Kharga represent cultural heritage of an outstanding universal value. Such those monuments have suffered weathering deterioration. There are various elements which affect the weathering process of stone monuments: climate conditions, shapes of cultural heritages, exposed time periods, terrains, and vegetation around them, etc. Among these, climate conditions are the most significant factor affecting the deterioration of Archeological sites in Egypt. El- Kharga Oasis belongs administratively to the New Valley Governorate. It is located in the southern part of the western desert of Egypt, lies between latitudes 22°30'14" and 26°00'00" N, and between 30°27'00" and 30°47'00" E. The area of El Kharga Oasis covers about 7500 square kilometers. Pilot studies were carried out on the EI-Nadura Temple, composed of sandstones originating from the great sand sea. The major objective of this study is to monitor and measure the weathering features and the weathering rate affecting the building stones forming El-Nadora Roman building rocks in cubic cm. To achieve these aims, the present study used analysis of climatic data such as annual and seasonal solar radiation, Monthly average number of hours of sunshine, maximum and minimum air temperatures, wind speed, which have obtained from actual field measurements and data Meteorological Authority of El-Kharga station for the period 1977 to 2010 (33 years), and from the period 1941-2050 (110 years) as a long term of temperature data. Several samples were collected and examined by polarizing microscopy (PLM), X-ray diffraction analysis (XRD) and scanning electron microscopy equipped with an energy dispersive X-ray analysis system (SEM-EDX). The results were in

Monitoring alkylphenols in water using the polar organic chemical integrative sampler (POCIS): Determining sampling rates via the extraction of PES membranes and Oasis beads.

PubMed

Silvani, Ludovica; Riccardi, Carmela; Eek, Espen; Papini, Marco Petrangeli; Morin, Nicolas A O; Cornelissen, Gerard; Oen, Amy M P; Hale, Sarah E

2017-10-01

Polar organic chemical integrative samplers (POCIS) have previously been used to monitor alkylphenol (AP) contamination in water and produced water. However, only the sorbent receiving phase of the POCIS (Oasis beads) is traditionally analyzed, thus limiting the use of POCIS for monitoring a range of APs with varying hydrophobicity. Here a "pharmaceutical" POCIS was calibrated in the laboratory using a static renewal setup for APs (from 2-ethylphenol to 4-n-nonylphenol) with varying hydrophobicity (log K ow between 2.47 and 5.76). The POCIS sampler was calibrated over its 28 day integrative regime and sampling rates (R s ) were determined. Uptake was shown to be a function of AP hydrophobicity where compounds with log K ow  < 4 were preferentially accumulated in Oasis beads, and compounds with log K ow  > 5 were preferentially accumulated in the PES membranes. A lag phase (over a 24 h period) before uptake in to the PES membranes occurred was evident. This work demonstrates that the analysis of both POCIS phases is vital in order to correctly determine environmentally relevant concentrations owing to the fact that for APs with log K ow  ≤ 4 uptake, to the PES membranes and the Oasis beads, involves different processes compared to APs with log K ow  ≥ 4. The extraction of both the POCIS matrices is thus recommended in order to assess the concentration of hydrophobic APs (log K ow  ≥ 4), as well as hydrophilic APs, most effectively. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

The COSMO-CLM 4.8 regional climate model coupled to regional ocean, land surface and global earth system models using OASIS3-MCT: description and performance

NASA Astrophysics Data System (ADS)

Will, Andreas; Akhtar, Naveed; Brauch, Jennifer; Breil, Marcus; Davin, Edouard; Ho-Hagemann, Ha T. M.; Maisonnave, Eric; Thürkow, Markus; Weiher, Stefan

2017-04-01

We developed a coupled regional climate system model based on the CCLM regional climate model. Within this model system, using OASIS3-MCT as a coupler, CCLM can be coupled to two land surface models (the Community Land Model (CLM) and VEG3D), the NEMO-MED12 regional ocean model for the Mediterranean Sea, two ocean models for the North and Baltic seas (NEMO-NORDIC and TRIMNP+CICE) and the MPI-ESM Earth system model.We first present the different model components and the unified OASIS3-MCT interface which handles all couplings in a consistent way, minimising the model source code modifications and defining the physical and numerical aspects of the couplings. We also address specific coupling issues like the handling of different domains, multiple usage of the MCT library and exchange of 3-D fields.We analyse and compare the computational performance of the different couplings based on real-case simulations over Europe. The usage of the LUCIA tool implemented in OASIS3-MCT enables the quantification of the contributions of the coupled components to the overall coupling cost. These individual contributions are (1) cost of the model(s) coupled, (2) direct cost of coupling including horizontal interpolation and communication between the components, (3) load imbalance, (4) cost of different usage of processors by CCLM in coupled and stand-alone mode and (5) residual cost including i.a. CCLM additional computations.Finally a procedure for finding an optimum processor configuration for each of the couplings was developed considering the time to solution, computing cost and parallel efficiency of the simulation. The optimum configurations are presented for sequential, concurrent and mixed (sequential+concurrent) coupling layouts. The procedure applied can be regarded as independent of the specific coupling layout and coupling details.We found that the direct cost of coupling, i.e. communications and horizontal interpolation, in OASIS3-MCT remains below 7 % of the CCLM stand

Microbial extremophiles from the 2008 Schirmacher Oasis Expedition: preliminary results

NASA Astrophysics Data System (ADS)

Hoover, Richard B.; Pikuta, Elena V.; Townsend, Alisa; Anthony, Joshua; Guisler, Melissa; McDaniel, Jasmine; Bej, Asim; Storrie-Lombardi, Michael

2008-08-01

Among the most interesting targets for Astrobiology research are the polar ice caps and the permafrost of Mars and the ice and liquid water bodies that may lie beneath the frozen crusts of comets, the icy moons of Jupiter (Europa, Io and Ganymede) and Saturn (Titan and Enceladus). The permanently ice-covered lakes of Antarctica, such as Lake Vostok and Lake Untersee, provide some of the best terrestrial analogues for these targets. The 2008 International Tawani Schirmacher Oasis/Lake Untersee Expeditions have been organized to conduct studies of novel microbial extremophiles and investigate the biodiversity of the glaciers and ice-covered lakes of Dronning Maud Land, East Antarctica. This paper describes the preliminary analysis of the anaerobic microbial extremophiles isolated from samples collected during the 2008 International Schirmacher Oasis Antarctica Reconnaissance Expedition. These samples showed great diversity of psychrophlic and psychrotolerant bacteria. Six new anaerobic strains have been isolated in pure cultures and partially characterized. Two of them (strains ARHSd-7G and ARHSd-9G) were isolated from a small tidal pool near the colony of African Penguins Spheniscus demersus. Strain ARHSd-7G was isolated on mineral anaerobic medium with 3 % NaCl, pH 7 and D-glucose, it has motile, vibrion shape cells, and is Gram variable. Strain ARHSd-9G grew on anaerobic, alkaline medium with pH 9 and 1 % NaCl at 3°C. The substrate was D-glucose supplemented with yeast extract (0.05 %). Cells of strain ARHSd-9G had morphology of straight or slightly curved elongated rods and demonstrated unusual optical effects under dark-field visible light microscopy. The cells were spore-forming and Gram positive. From the mat sample collected near Lake Zub, the new strain LZ-3 was isolated in pure culture at 3°C. Strain LZ-3 was anaerobic and grew on 0.5 % NaCl mineral medium with Dglucose as a substrate. The gram positive cells were spore-forming. They exhibited a

Effective determination of a pharmaceutical, sulpiride, in river water by online SPE-LC-MS using a molecularly imprinted polymer as a preconcentration medium.

PubMed

Kubo, Takuya; Kuroda, Kenta; Tominaga, Yuichi; Naito, Toyohiro; Sueyoshi, Kenji; Hosoya, Ken; Otsuka, Koji

2014-02-01

We report an effective and a quantitative analysis method for one of pharmaceuticals, sulpiride, in river water by online solid phase extraction (SPE) connected with liquid chromatography-mass spectrometry (LC-MS) using a molecularly imprinted polymer as a preconcentration medium. The polymer prepared with a pseudo template molecule showed the selective retention ability based on the interval recognition of functional groups in sulpiride. Also, the imprinted polymer provided an effective concentration of a trace level of sulpiride in offline SPE with dual washing processes using water and acetonitrile, although another imprinted polymer prepared by an authentic method using sulpiride and methacrylic acid as a template and a functional monomer, respectively, showed the selective adsorption only in organic solvents. Furthermore, we employed the imprinted polymer as the preconcentration column of online SPE-LC-MS and the results supposed that the proposed system allowed the quantitative analysis of sulpiride with high sensitivity and recovery (10ng/L at 96%). Additionally, the determination of sulpiride in real river water without an additional spiking was effectively achieved by the system. Copyright © 2013 Elsevier B.V. All rights reserved.

Development of an SPE/CE method for analyzing HAAs

USGS Publications Warehouse

Zhang, L.; Capel, P.D.; Hozalski, R.M.

2007-01-01

The haloacetic acid (HAA) analysis methods approved by the US Environmental Protection Agency involve extraction and derivatization of HAAs (typically to their methyl ester form) and analysis by gas chromatography (GC) with electron capture detection (ECD). Concerns associated with these methods include the time and effort of the derivatization process, use of potentially hazardous chemicals or conditions during methylation, poor recoveries because of low extraction efficiencies for some HAAs or matrix effects from sulfate, and loss of tribromoacetic acid because of decarboxylation. The HAA analysis method introduced here uses solid-phase extraction (SPE) followed by capillary electrophoresis (CE) analysis. The method is accurate, reproducible, sensitive, relatively safe, and easy to perform, and avoids the use of large amounts of solvent for liquid-liquid extraction and the potential hazards and hassles of derivatization. The cost of analyzing HAAs using this method should be lower than the currently approved methods, and utilities with a GC/ECD can perform the analysis in-house.

A multi-residue method for the analysis of pesticides and pesticide degradates in water using HLB solid-phase extraction and gas chromatography-ion trap mass spectrometry

USGS Publications Warehouse

Hladik, M.L.; Smalling, K.L.; Kuivila, K.M.

2008-01-01

A method was developed for the analysis of over 60 pesticides and degradates in water by HLB solid-phase extraction and gas-chromatography/mass spectrometry. Method recoveries and detection limits were determined using two surface waters with different dissolved organic carbon (DOC) concentrations. In the lower DOC water, recoveries and detection limits were 80%-108% and 1-12 ng/L, respectively. In the higher DOC water, the detection limits were slightly higher (1-15 ng/L). Additionally, surface water samples from four sites were analyzed and 14 pesticides were detected with concentrations ranging from 4 to 1,200 ng/L. ?? 2008 Springer Science+Business Media, LLC.

Quaternary history of the Kiseiba Oasis region, southern Egypt

NASA Astrophysics Data System (ADS)

Maxwell, Ted A.; Haynes, C. Vance; Nicoll, Kathleen; Johnston, Andrew K.; Grant, John A.; Kilani, Ali

2017-12-01

Kiseiba Oasis and depression are located in southern Egypt between the Selima Sand Sheet to the west and the Nile to the east, an important area that hosted Late Cenozoic drainage, Middle Pleistocene lakes, and numerous Paleolithic and Neolithic cultural sites. A synthesis of orbital data, field surveying and near-surface stratigraphy provides new insights into the Quaternary history of this region. Shuttle Imaging Radar data show a complex of fluvial channels that are due to stringers of surficial fluvial lag, subsurface fluvial deposits, and areas of deep alluvium. Three topographic surfaces are described: 1) the Atmur El-Kibeish, above 230 m elevation, which displays a linear pattern of light radar returns, possibly formed from northeast drainage; 2) the Acheulean Surface, at 200 m elevation, that has dark radar patterns resulting from thick alluvium bounded by pebble sand and calcrete strata, and 3) the Kiseiba Surface, below 190 m, that has a complex series of surface and subsurface fluvial and aeolian sediments. Initial drainage from the Early through Middle Pleistocene was to the northeast, which may have lasted through the Last Interglacial. Later reworking of sediments during the Last Glacial Maximum and the Holocene resulted in topographic inversion, with any subsequent local drainage on the Kiseiba Surface to the southwest, towards the Kiseiba Scarp.

Draft Genome Sequence of Janthinobacterium sp. Ant5-2-1, Isolated from Proglacial Lake Podprudnoye in the Schirmacher Oasis of East Antarctica.

PubMed

Koo, Hyunmin; Strope, Bailey M; Kim, Eddy H; Shabani, Adel M; Kumar, Ranjit; Crowley, Michael R; Andersen, Dale T; Bej, Asim K

2016-01-21

Janthinobacterium sp. Ant5-2-1, isolated from the Schirmacher Oasis of East Antarctica, produces a purple-violet pigment, manifests diverse energy metabolism abilities, and tolerates cold, ultraviolet radiation, and other environmental stressors. We report here the 6.19-Mb draft genome of strain Ant5-2-1, which will help understand its survival mechanisms in extreme Antarctic ecosystems. Copyright © 2016 Koo et al.

Implementation of ground penetrating radar and electrical resistivity tomography for inspecting the Greco-Roman Necropolis at Kilo 6 of the Golden Mummies Valley, Bahariya Oasis, Egypt

NASA Astrophysics Data System (ADS)

Abbas, Abbas M.; Ghazala, Hosni H.; Mesbah, Hany S.; Atya, Magdy A.; Radwan, Ali; Hamed, Diaa E.

2016-06-01

Bahariya Oasis is one of the lately inspected spots in Egypt and has a long historical record extending from the old kingdom till the emergence of Islam. Since June 1999, the Valley of the Golden Mummies near Bawiti (at kilometer 6 on the road leads to Farafra Oasis) became significant due to the discoveries of amazing mummies of gelded faces. The archeologists believe that the Valley has more valuable tombs that still unrevealed. Also, the possibility that the Greco-Roman Necropolis extends to areas other than Kilo-6 is sustainable. The ground penetrating radar and electrical resistivity tomography are two geophysical tools that have successful applications in archeological assessment. The two techniques were used in integration plan to assert the archeological potentiality of the studied site and to map the feasible tombs. Sum of 798 GPR profiles and 19 ERT cross sections was carried out over the study area. The results of them were analyzed to envisage these results in archeological terms.

[Determination of 44 organophosphorus pesticides in food by SPE disk extraction-capillary gas chromatography with pulsed flame photometric detection].

PubMed

Luo, Xiao-Fei; Yang, Yuan; Sun, Cheng-Jun

2012-01-01

To develop a method for the simultaneous determination of 44 organophosphorus pesticides in food by SPE disk extraction-capillary gas chromatography with pulsed flame photometric detection. Organophosphorus pesticides in food were extracted ultrasonically with water. Then the extract was cleaned-up with SPE disk and eluted with ethyl acetate. Finally the eluent was condensed to 1mL under N2 at 55 degrees C. Gas chromatography was applied for quantitative detection of the organophosphorus pesticides in the sample. The linear range of the method for all the pesticides were in the range of 0.01-0.5 mg/kg with correlation coefficients of 0.992-1.000. The detection limits of the method were in the range of 0.0005-0.01 mg/kg. The recoveries for most pesticides were 60%-120% with relative standard deviations of less than 15%. The method is simple, sensitive, environmentally friendly and suitable for the determination of organophosphorous pesticides in food.

Coupling hydrodynamic and wave propagation modeling for waveform modeling of SPE.

NASA Astrophysics Data System (ADS)

Larmat, C. S.; Steedman, D. W.; Rougier, E.; Delorey, A.; Bradley, C. R.

2015-12-01

The goal of the Source Physics Experiment (SPE) is to bring empirical and theoretical advances to the problem of detection and identification of underground nuclear explosions. This paper presents effort to improve knowledge of the processes that affect seismic wave propagation from the hydrodynamic/plastic source region to the elastic/anelastic far field thanks to numerical modeling. The challenge is to couple the prompt processes that take place in the near source region to the ones taking place later in time due to wave propagation in complex 3D geologic environments. In this paper, we report on results of first-principles simulations coupling hydrodynamic simulation codes (Abaqus and CASH), with a 3D full waveform propagation code, SPECFEM3D. Abaqus and CASH model the shocked, hydrodynamic region via equations of state for the explosive, borehole stemming and jointed/weathered granite. LANL has been recently employing a Coupled Euler-Lagrange (CEL) modeling capability. This has allowed the testing of a new phenomenological model for modeling stored shear energy in jointed material. This unique modeling capability has enabled highfidelity modeling of the explosive, the weak grout-filled borehole, as well as the surrounding jointed rock. SPECFEM3D is based on the Spectral Element Method, a direct numerical method for full waveform modeling with mathematical accuracy (e.g. Komatitsch, 1998, 2002) thanks to its use of the weak formulation of the wave equation and of high-order polynomial functions. The coupling interface is a series of grid points of the SEM mesh situated at the edge of the hydrodynamic code domain. Displacement time series at these points are computed from output of CASH or Abaqus (by interpolation if needed) and fed into the time marching scheme of SPECFEM3D. We will present validation tests and waveforms modeled for several SPE tests conducted so far, with a special focus on effect of the local topography.

Moment-Tensor Spectra of Source Physics Experiments (SPE) Explosions in Granite

NASA Astrophysics Data System (ADS)

Yang, X.; Cleveland, M.

2016-12-01

We perform frequency-domain moment tensor inversions of Source Physics Experiments (SPE) explosions conducted in granite during Phase I of the experiment. We test the sensitivity of source moment-tensor spectra to factors such as the velocity model, selected dataset and smoothing and damping parameters used in the inversion to constrain the error bound of inverted source spectra. Using source moments and corner frequencies measured from inverted source spectra of these explosions, we develop a new explosion P-wave source model that better describes observed source spectra of these small and over-buried chemical explosions detonated in granite than classical explosion source models derived mainly from nuclear-explosion data. In addition to source moment and corner frequency, we analyze other features in the source spectra to investigate their physical causes.

The Source Physics Experiments (SPE) at the Nevada National Security Site (NNSS): An Overview

NASA Astrophysics Data System (ADS)

Snelson, C. M.; Chipman, V.; White, R. L.; Emmitt, R.; Townsend, M.; Barker, D.; Lee, P.

2012-12-01

Understanding the changes in seismic energy as it travels from the near field to the far field is the ultimate goal in monitoring for explosive events of interest. This requires a clear understanding of explosion phenomenology as it relates to seismic, infrasound, and acoustic signals. Although there has been much progress in modeling these phenomena, this has been primarily based in the empirical realm. As a result, the logical next step in advancing the seismic monitoring capability of the United States is to conduct field tests that can expand the predictive capability of the physics-based modeling currently under development. The Source Physics Experiment at the Nevada National Security Site (SPE) is the first step in this endeavor to link the empirically based with the physics-based modeling. This is a collaborative project between National Security Technologies (NSTec), Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Sandia National Laboratories (SNL), the Defense Threat Reduction Agency (DTRA), and the Air Force Technical Applications Center (AFTAC). The test series require both the simple and complex cases to fully characterize the problem, which is to understand the transition of seismic energy from the near field to the far field; to understand the development of S-waves in explosives sources; and how anisotropy controls seismic energy transmission and partitioning. The current series is being conducted in a granite body called the Climax Stock. This location was chosen for several reasons, including the fairly homogenous granite; the location of previous nuclear tests in the same rock body; and generally the geology has been well characterized. The simple geology series is planned for 7 shots using conventional explosives in the same shot hole surrounded by Continuous Reflectometry for Radius vs. Time Experiment (CORRTEX), Time of Arrival (TOA), Velocity of Detonation (VOD), down-hole accelerometers, surface

Effects of climate change on phenological trends and seed cotton yields in oasis of arid regions.

PubMed

Huang, Jian; Ji, Feng

2015-07-01

Understanding the effects of climatic change on phenological phases of cotton (Gossypium hirsutum L.) in oasis of arid regions may help optimize management schemes to increase productivity. This study assessed the impacts of climatic changes on the phenological phases and productivity of spring cotton. The results showed that climatic warming led the dates of sowing seed, seeding emergence, three-leaf, five-leaf, budding, anthesis, full bloom, cleft boll, boll-opening, boll-opening filling, and stop-growing become earlier by 24.42, 26.19, 24.75, 23.28, 22.62, 15.75, 14.58, 5.37, 2.85, 8.04, and 2.16 days during the period of 1981-2010, respectively. The growth period lengths from sowing seed to seeding emergence and from boll-opening to boll-opening filling were shortened by 1.76 and 5.19 days, respectively. The other growth period lengths were prolonged by 2-9.71 days. The whole growth period length was prolonged by 22.26 days. The stop-growing date was delayed by 2.49-3.46 days for every 1 °C rise in minimum, maximum, and mean temperatures; however, other development dates emerged earlier by 2.17-4.76 days. Rising temperatures during the stage from seeding emergence to three-leaf reduced seed cotton yields. However, rising temperatures increased seed cotton yields in the two stages from anthesis to cleft boll and from boll-opening filling to the stop-growing. Increasing accumulated temperatures (AT) had different impacts on different development stages. During the vegetative phase, rising AT led to reduced seed cotton yields, but rising AT during reproductive stage increased seed cotton yields. In conclusion, climatic warming helpfully obtained more seed cotton yields in oasis of arid regions in northwest China. Changing the sowing date is another way to enhance yields for climate change in the future.

Draft Genome Sequence of Salmonella enterica subsp. enterica Serovar Infantis Strain SPE101, Isolated from a Chronic Human Infection

PubMed Central

Iriarte, Andrés; Giner-Lamia, Joaquín; Betancor, Laura; Astocondor, Lizeth; Cestero, Juan J.; Ochoa, Theresa; García, Coralith; Puente, José L.; Chabalgoity, José A.

2017-01-01

ABSTRACT We report a 4.99-Mb draft genome sequence of Salmonella enterica subsp. enterica serovar Infantis strain SPE101, isolated from feces of a 5-month-old breast-fed female showing diarrhea associated with severe dehydration and malnutrition. The infection prolonged for 6 months despite antibiotic treatment. PMID:28729277

Characteristics of Four SPE Classes According to Onset Timing and Proton Acceleration Patterns

NASA Astrophysics Data System (ADS)

Kim, Roksoon

2015-04-01

In our previous work (Kim et al., 2015), we suggested a new classification scheme, which categorizes the SPEs into four groups based on association with flare or CME inferred from onset timings as well as proton acceleration patterns using multienergy observations. In this study, we have tried to find whether there are any typical characteristics of associated events and acceleration sites in each group using 42 SPEs from 1997 to 2012. We find: (i) if the proton acceleration starts from a lower energy, a SPE has a higher chance to be a strong event (> 5000 pfu) even if the associated flare and CME are not so strong. The only difference between the SPEs associated with flare and CME is the location of the acceleration site. For the former, the sites are very low ( ~1 Rs) and close to the western limb, while the latter has a relatively higher (mean=6.05 Rs) and wider acceleration sites. (ii) When the proton acceleration starts from the higher energy, a SPE tends to be a relatively weak event (< 1000 pfu), in spite of its associated CME is relatively stronger than previous group. (iii) The SPEs categorized by the simultaneous proton acceleration in whole energy range within 10 minutes, tend to show the weakest proton flux (mean=327 pfu) in spite of strong related eruptions. Their acceleration heights are very close to the locations of type II radio bursts. Based on those results, we suggest that the different characteristics of the four groups are mainly due to the different mechanisms governing the acceleration pattern and interval, and different condition such as the acceleration location.

A new isolation method for biomass-burning tracers in snow: Measurements of p-hydroxybenzoic, vanillic, and dehydroabietic acids

NASA Astrophysics Data System (ADS)

Gao, Shaopeng; Liu, Dameng; Kang, Shichang; Kawamura, Kimitaka; Wu, Guangming; Zhang, Guoshuai; Cong, Zhiyuan

2015-12-01

Organic acids such as p-hydroxybenzoic, vanillic, and dehydroabietic acids are unique biomass-burning tracers for black carbon (BC) and dissolved organic carbon (DOC) in the snow of mountain glaciers, Arctic and Antarctic ice sheets. In this study, we developed a method by solid-phase extraction (SPE) coupled with gas chromatography/ion trap mass spectrometry for the determination of those organic acids in snow. The limit of detection (LOD) is 0.002, 0.001, 0.004 ng mL-1 for p-hydroxybenzoic, vanillic, and dehydroabietic acids, respectively. For p-hydroxybenzoic and vanillic acids, all the four SPE cartridges used produce good recoveries (>75%). However, for dehydroabietic acid, HLB cartridge has much better performance than DPA, FEP-2 and PAX cartridges. The method was applied to the snow samples collected from Zhadang Glacier in the Tibetan Plateau (TP), and demonstrated its feasibility in pretreating and detecting of these target compounds. We found that BC and DOC accumulated in the snow during winter and spring over the TP glaciers are mainly derived from biomass burning. This result demonstrates the capability of our analytical method for a deep understanding on the source of carbonaceous materials in snow.

Draft Genome Sequence of Salmonella enterica subsp. enterica Serovar Infantis Strain SPE101, Isolated from a Chronic Human Infection.

PubMed

Iriarte, Andrés; Giner-Lamia, Joaquín; Silva, Claudia; Betancor, Laura; Astocondor, Lizeth; Cestero, Juan J; Ochoa, Theresa; García, Coralith; Puente, José L; Chabalgoity, José A; García-Del Portillo, Francisco

2017-07-20

We report a 4.99-Mb draft genome sequence of Salmonella enterica subsp. enterica serovar Infantis strain SPE101, isolated from feces of a 5-month-old breast-fed female showing diarrhea associated with severe dehydration and malnutrition. The infection prolonged for 6 months despite antibiotic treatment. Copyright © 2017 Iriarte et al.

The occurrence and source identification of bisphenol compounds in wastewaters.

PubMed

Česen, Marjeta; Lenarčič, Kaja; Mislej, Vesna; Levstek, Meta; Kovačič, Ana; Cimrmančič, Bernardka; Uranjek, Nataša; Kosjek, Tina; Heath, David; Dolenc, Marija Sollner; Heath, Ester

2018-03-01

This study reports the occurrence of eight bisphenols (BPs): bisphenol AF (BPAF), bisphenol AP (BPAP), bisphenol B (BPB), bisphenol C (BPC), bisphenol E (BPE), bisphenol F (BPF), bisphenol S (BPS) and bisphenol Z (BPZ) in wastewaters (WWs). Sample preparation involved pre-concentration with SPE cartridges (Oasis HLB), followed by derivatization using N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide with 1% tert-butyldimethylchlorosilane. Chemical analysis was based on gas chromatography-mass spectrometry. A validated method with limits of detection (LODs) at ngL -1 range was applied to WWs collected at five Slovene wastewater treatment plants (WWTPs) and WW inflows from industrial, commercial and residential sources entering the sewerage systems of two catchments (Domžale-Kamnik (DK) and Ljubljana (LJ)). The presence of all BPs was confirmed in three inflows in DK and two inflows in the LJ catchments. High cumulative concentrations of all BPs were determined in WW from food processing facilities (LJ: 3030ngL -1 and DK: 599ngL -1 ). A high detection frequency was observed in the WW from two textile cleaning companies (6 BPs for LJ and 8 BPs for DK). The analysis of WW from WWTPs revealed that only BPF (36.7ngL -1 ) and BPS (40.6ngL -1 ) were >LODs in the influents, whereas other BPs were detected also in the effluents. BPZ was found in the highest concentration (403ngL -1 at WWTP-DK). WW collected at this WWTP also contained the highest amount of BPE (238ngL -1 ). Although BPs removal could not be directly compared between the WWTPs, with the exception of BPAP and BPB in the case of two smaller WWTPs (6.39%-43.2%) bisphenols were in general highly removed (≥96.2%). Finally, levels of BPC>LOD are reported for first time (WWTP in the DK catchment: 1.01ngL -1 -11.8ngL -1 ; LJ inflow from food processing plant up to 2560ngL -1 ). Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Use of Satellite Imagery to Monitor the Oasis Agriculture in the Turpan Depression, Xinjiang Uygur Autonomous Region, People’s Republic of China--A Case Study.

DTIC Science & Technology

1981-05-01

drops at its lowest point to 154 meters below sea level and presents a varied natural panorama of desert, oasis, gorges and sand dunes. The chief...Febr’iarv each :ear AraiKawa. Ab’ . -. 25 Thermal conditions in the depression are similar to those in North China, but the amount of precipitation is

Optimisation and validation of the analytical procedure for the determination of acrylamide in coffee by LC-MS/MS with SPE clean up.

PubMed

Gielecińska, Iwona; Mojska, Hanna

2013-01-01

Numerous studies have demonstrated acrylamide to be both neurotoxic and carcinogenic. At present it is widely recognised that acrylamide is mainly formed through the Maillard reaction from free asparagine and reducing sugars. The major sources of dietary acrylamide are potato products, processed cereals and coffee. To optimise and validate an analytical method for determining acrylamide in coffee by liquid chromatography and tandem mass spectrometry analysis (LC/MS/MS) using SPE clean-up. Analytical separation of acrylamide from roasted coffee was performed by liquid chromatography using a Hypercarb column followed by LC/MS/MS analysis, with 2,3,3-d3 acrylamide as an internal standard. The method was based on two purification steps: the first with hexane and Carrez solutions in order to remove of fat and to precipitate proteins, respectively; and the second with a solid-phase extraction (SPE) column which proved to be efficient in the elimination of the main chromatographic interferences. Limit of quantification (LOQ) for measuring acrylamide in coffee was 50 microg/kg. The described method demonstrates satisfactory precision (RSD = 2.5%), repeatability (RSD = 9.2%) and accuracy (mean recovery - 97.4%). Our results confirm that LC-MS/MS with SPE clean-up is selective and suitable for determination of acrylamide in coffee. Indeed, this method meets the criteria of EU Commission Recommendations (No. 2007/331/EC and No. 2010/307/EU), on the monitoring of acrylamide levels in food.

Orally administered fructose increases the numbers of peripheral lymphocytes reduced by exposure of mice to gamma or SPE-like proton radiation

NASA Astrophysics Data System (ADS)

Romero-Weaver, A. L.; Ni, J.; Lin, L.; Kennedy, A. R.

2014-07-01

Exposure of the whole body or a major portion of the body to ionizing radiation can result in Acute Radiation Sickness (ARS), which can cause symptoms that range from mild to severe, and include death. One of the syndromes that can occur during ARS is the hematopoietic syndrome, which is characterized by a reduction in bone marrow cells as well as the number of circulating blood cells. Doses capable of causing this syndrome can result from conventional radiation therapy and accidental exposure to ionizing radiation. It is of concern that this syndrome could also occur during space exploration class missions in which astronauts could be exposed to significant doses of solar particle event (SPE) radiation. Of particular concern is the reduction of lymphocytes and granulocytes, which are major components of the immune system. A significant reduction in their numbers can compromise the immune system, causing a higher risk for the development of infections which could jeopardize the success of the mission. Although there are no specific countermeasures utilized for the ARS resulting from exposure to space radiation(s), granulocyte colony-stimulating factor (G-CSF) has been proposed as a countermeasure for the low number of neutrophils caused by SPE radiation, but so far no countermeasure exists for a reduced number of circulating lymphocytes. The present study demonstrates that orally administered fructose significantly increases the number of peripheral lymphocytes reduced by exposure of mice to 2 Gy of gamma- or SPE-like proton radiation, making it a potential countermeasure for this biological end-point.

Simultaneous determination of thirteen different steroid hormones using micro UHPLC-MS/MS with on-line SPE system.

PubMed

Márta, Zoltán; Bobály, Balázs; Fekete, Jenő; Magda, Balázs; Imre, Tímea; Mészáros, Katalin Viola; Bálint, Mária; Szabó, Pál Tamás

2018-02-20

Ultratrace analysis of sample components requires excellent analytical performance in terms of limits of quantitation (LOQ). Micro UHPLC coupled to sensitive tandem mass spectrometry provides state of the art solution for such analytical problems. Using on-line SPE with column switching on a micro UHPLC-MS/MS system allowed to decrease LOQ without any complex sample preparation protocol. The presented method is capable of reaching satisfactory low LOQ values for analysis of thirteen different steroid molecules from human plasma without the most commonly used off-line SPE or compound derivatization. Steroids were determined by using two simple sample preparation methods, based on lower and higher plasma steroid concentrations. In the first method, higher analyte concentrations were directly determined after protein precipitation with methanol. The organic phase obtained from the precipitation was diluted with water and directly injected into the LC-MS system. In the second method, low steroid levels were determined by concentrating the organic phase after steroid extraction. In this case, analytes were extracted with ethyl acetate and reconstituted in 90/10 water/acetonitrile following evaporation to dryness. This step provided much lower LOQs, outperforming previously published values. The method has been validated and subsequently applied to clinical laboratory measurement. Copyright © 2017 Elsevier B.V. All rights reserved.

Draft Genome Sequence of Hymenobacter sp. Strain IS2118, Isolated from a Freshwater Lake in Schirmacher Oasis, Antarctica, Reveals Diverse Genes for Adaptation to Cold Ecosystems

PubMed Central

Ptacek, Travis; Crowley, Michael; Swain, Ashit K.; Osborne, John D.; Bej, Asim K.; Andersen, Dale T.

2014-01-01

Hymenobacter sp. IS2118, isolated from a freshwater lake in Schirmacher Oasis, Antarctica, produces extracellular polymeric substance (EPS) and manifests tolerance to cold, UV radiation (UVR), and oxidative stress. We report the 5.26-Mb draft genome of strain IS2118, which will help us to understand its adaptation and survival mechanisms in Antarctic extreme ecosystems. PMID:25103756

Ground-penetrating radar exploration for ancient monuments at the Valley of Mummies -Kilo 6, Bahariya Oasis, Egypt

NASA Astrophysics Data System (ADS)

Shaaban, Fathy A.; Abbas, Abbas M.; Atya, Magdy A.; Hafez, Mahfouz A.

2009-06-01

A Valley of Mummies was discovered recently by an Egyptian team at Bahariya Oasis, located about 380 km west of the pyramids. Four tombs were excavated, and inside them were found one hundred and five mummies (105), many of them beautifully gilded. These mummies, many sumptuously decorated with religious scenes, are the very best Roman-Period mummies ever found in Egypt. These remains are around 2000 years old, but they are in remarkable condition. A Ground-Penetrating Radar (GPR) had proved successful in detecting the cavities in resistive soil in which the mummies were found. The GPR survey conducted near the earlier-discovered tombs at Kilo-6 El-Bahariya to Farafra Oasis road is the focus of this paper. The GPR survey was conducted using the SIR-2000 attached to a 200 MHz monostatic antenna. The two areas to be surveyed were selected by the archaeologists in situ. Area one was 40 m × 40 m and Area two was 30 m × 15 m. A grid pattern survey in one direction; with one-meter profile spacing was done to both areas. In addition, a focusing survey was undertaken over the entire Area one. In addition, twenty long GPR profiles were conducted in an attempt to determine the outer, expected limits of the burial area. After the data acquisition, Reflex software was used for data processing and presentation. The final results of the radar survey: in the form of 2D radar records, time slices and 3D block diagrams; were used to guide the archaeologists during the excavation process. The excavation processes have been completed by the archaeologists, and many tombs and mummies were discovered. It is worthy to mention that, the excavations and location of tombs and cavities matched strongly with the GPR results.

Uranus' cloud structure and scattering particle properties from IRTF SpeX observations

NASA Astrophysics Data System (ADS)

Tice, D. S.; Irwin, P. G. J.; Fletcher, L. N.; Teanby, N. A.; Orton, G. S.; Davis, G. R.

2011-10-01

Observations of Uranus were made in August 2009 with the SpeX spectrograph at the NASA Infrared Telescope Facility (IRTF). Analysed spectra range from 0.8 to 1.8 μm at a spatial resolution of 0.5" and a spectral resolution of R = 1,200. Spectra from 0.818 to 0.834 μm, a region characterised by both strong hydrogen quadrupole and methane absorptions are considered to determine methane content. Evidence indicates that methane abundance varies with latitude. NEMESIS, an optimal estimation retrieval code with full-scattering capability, is employed to analyse the full range of data. Cloud and haze properties in the upper troposphere and stratosphere are characterised, and are consistent with other current literature. New information on single scattering albedos and particle size distributions are inferred.

Characterization of magnetic spherical fractions in sand deposits for interpretation of environmental change around the El- Zayyan temple, Kharga Oasis, Western Desert, Egypt

NASA Astrophysics Data System (ADS)

Watanabe, Makiko; Koizumi, Natsuko; Kato, Sayuri; Kikuchi, Ryohei; Kamei, Hiroyuki

2014-05-01

Desertification in North Africa has rapidly advanced over the last 6,000 years. Such environmental changes began in the Early Dynastic Period of Egypt (4200 - 3150 BC), and the occupation of Achaemenid Persian and Roman cultures in Egypt occurred under even drier climates. Kharga is the largest oasis of the five oases, located in the western desert of Egypt that contains a treasure trove of archaeological resources. This oasis has been highlighted to promote resource exploration and development of archaeological tourism since the 1980's. The El-Zayyan temple is located 27 km south of the central Kharga oasis. Zayyan was once called 'Tchonemyris', which has connection with the means of 'huge well' in Greek. Although major portions of the temple were rebuilt in 140 AD during the rule of the Roman Emperor Antoninus Pius, this temple is considered to be originally built in the Ptolemaic period (4c-1c BC). It is likely that the area had a sufficient water supply in the past as the El-Zayyan temple stands at the lowest point (-18 m a.s.l.) in the Kharga oasis. Furthermore, the El-Ghueita temple that stands on a hill top at 68.5 m a.s.l., 4 km northward from the El-Zayyan temple, has given name that means 'beautiful garden' in Greek. From these facts, we can imagine that the past landscape of this area contained green surroundings. The El-Ghueita temple was well known as a production centre of high quality wine since the mid-Dynastic age (2050 -1786 BC). As this area is currently arid, it is expected that there were irrigation facilities to maintain the vast farm land during the ancient period. To deepen our knowledge of how people developed their technologies and conducted their life within the natural environment of a drastic drying period, understanding the process of environmental change on a region scale is necessary. The aim of this study was to extract proxies from sand deposits in the western desert area to estimate the change in the environment. We examined the

Robust trace analysis of polar (C2-C8) perfluorinated carboxylic acids by liquid chromatography-tandem mass spectrometry: method development and application to surface water, groundwater and drinking water.

PubMed

Janda, Joachim; Nödler, Karsten; Brauch, Heinz-Jürgen; Zwiener, Christian; Lange, Frank T

2018-03-19

A simple and robust analytical method for the determination of perfluorinated carboxylic acids (PFCAs) with C 2 to C 8 chains, based on solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), was developed, validated and applied to tap water, groundwater and surface water. Two stationary phases for LC (Obelisc N and Kinetex C 18 ) and two materials with weak anion-exchange properties for SPE (Strata X-AW and Oasis WAX) were evaluated. Robust separation and retention was achieved with the reversed phase column and an acidic eluent. Quantitative extraction recoveries were generally achieved for PFCAs with C > 3, but extraction efficiencies were different for the two shortest chained analytes: 36 to 114% of perfluoropropanoate (PFPrA) and 14 to 99% of trifluoroacetate (TFA) were recovered with Strata X-AW, while 93 to 103% of PFPrA and 40 to 103% of TFA were recovered with Oasis WAX. The sample pH was identified as a key parameter in the extraction process. One-step elution-filtration was introduced in the workflow, in order to remove sorbent particles and minimise sample preparation steps. Validation resulted in limits of quantification for all PFCAs between 0.6 and 26 ng/L. Precision was between 0.7 and 15% and mean recoveries ranged from 83 to 107%. In groundwater samples from sites impacted by per- and polyfluoroalkyl substances (PFASs), PFCA concentrations ranged from 0.056 to 2.2 μg/L. TFA and perfluorooctanoate were the predominant analytes. TFA, however, revealed a more ubiquitous occurrence and was found in concentrations between 0.045 and 17 μg/L in drinking water, groundwater and surface water, which were not impacted by PFASs.

Draft Genome Sequence of Hymenobacter sp. Strain IS2118, Isolated from a Freshwater Lake in Schirmacher Oasis, Antarctica, Reveals Diverse Genes for Adaptation to Cold Ecosystems.

PubMed

Koo, Hyunmin; Ptacek, Travis; Crowley, Michael; Swain, Ashit K; Osborne, John D; Bej, Asim K; Andersen, Dale T

2014-08-07

Hymenobacter sp. IS2118, isolated from a freshwater lake in Schirmacher Oasis, Antarctica, produces extracellular polymeric substance (EPS) and manifests tolerance to cold, UV radiation (UVR), and oxidative stress. We report the 5.26-Mb draft genome of strain IS2118, which will help us to understand its adaptation and survival mechanisms in Antarctic extreme ecosystems. Copyright © 2014 Koo et al.

[Characteristics of soil nematode community along an age sequence of sandy desert soil cultivation in a marginal oasis of middle reaches of Heihe River].

PubMed

Wang, Xue-Feng; Su, Yong-Zhong; Yang, Rong

2010-08-01

This paper studied the characteristics of soil nematode community following the conversion of native sandy desert soil to irrigated farmland in a marginal oasis of the middle reaches of Heihe River basin, aimed to approach the bioindicating function of soil nematodes in soil evolution process. A total of 27921 soil nematode individuals were captured, belonging to 25 families and 34 genera. The total number of nematodes increased gradually with increasing age of cultivation. At all sampling sites, bacterivores and plant parasites were the dominant trophic groups, and made up the main parts of nematode community in oasis farmland. Through the analysis of the evenness index (J) and dominance index (lambda) of nematode community, the ecosystems were found to be fragile for the farmlands having cultivated for 0, 10, and > 50 years. The maturity index MI2-5 and MMI decreased with increasing cultivation age, suggesting that the practice of agricultural use enhanced the disturbance on farmland. The soil properties changed significantly after 10 years of cultivation, which was at a significant change stage for the structure stability of soil ecosystems. The characteristics of soil nematode community could be used as the bioindicator of soil evolution following the conversion of native desert soil to irrigated farmland.

SPE-IMS-MS: An automated platform for sub-sixty second surveillance of endogenous metabolites and xenobiotics in biofluids

DOE PAGES

Zhang, Xing; Romm, Michelle; Zheng, Xueyun; ...

2016-12-29

Characterization of endogenous metabolites and xenobiotics is essential to deconvoluting the genetic and environmental causes of disease. However, surveillance of chemical exposure and disease-related changes in large cohorts requires an analytical platform that offers rapid measurement, high sensitivity, efficient separation, broad dynamic range, and application to an expansive chemical space. Here in this article, we present a novel platform for small molecule analyses that addresses these requirements by combining solid-phase extraction with ion mobility spectrometry and mass spectrometry (SPE-IMS-MS). This platform is capable of performing both targeted and global measurements of endogenous metabolites and xenobiotics in human biofluids with highmore » reproducibility (CV ≤ 3%), sensitivity (LODs in the pM range in biofluids) and throughput (10-s sample-to-sample duty cycle). We report application of this platform to the analysis of human urine from patients with and without type 1 diabetes, where we observed statistically significant variations in the concentration of disaccharides and previously unreported chemical isomers. Lastly, this SPE-IMS-MS platform overcomes many of the current challenges of large-scale metabolomic and exposomic analyses and offers a viable option for population and patient cohort screening in an effort to gain insights into disease processes and human environmental chemical exposure.« less

SPE-IMS-MS: An automated platform for sub-sixty second surveillance of endogenous metabolites and xenobiotics in biofluids.

PubMed

Zhang, Xing; Romm, Michelle; Zheng, Xueyun; Zink, Erika M; Kim, Young-Mo; Burnum-Johnson, Kristin E; Orton, Daniel J; Apffel, Alex; Ibrahim, Yehia M; Monroe, Matthew E; Moore, Ronald J; Smith, Jordan N; Ma, Jian; Renslow, Ryan S; Thomas, Dennis G; Blackwell, Anne E; Swinford, Glenn; Sausen, John; Kurulugama, Ruwan T; Eno, Nathan; Darland, Ed; Stafford, George; Fjeldsted, John; Metz, Thomas O; Teeguarden, Justin G; Smith, Richard D; Baker, Erin S

2016-12-01

Characterization of endogenous metabolites and xenobiotics is essential to deconvoluting the genetic and environmental causes of disease. However, surveillance of chemical exposure and disease-related changes in large cohorts requires an analytical platform that offers rapid measurement, high sensitivity, efficient separation, broad dynamic range, and application to an expansive chemical space. Here, we present a novel platform for small molecule analyses that addresses these requirements by combining solid-phase extraction with ion mobility spectrometry and mass spectrometry (SPE-IMS-MS). This platform is capable of performing both targeted and global measurements of endogenous metabolites and xenobiotics in human biofluids with high reproducibility (CV 6 3%), sensitivity (LODs in the pM range in biofluids) and throughput (10-s sample-to-sample duty cycle). We report application of this platform to the analysis of human urine from patients with and without type 1 diabetes, where we observed statistically significant variations in the concentration of disaccharides and previously unreported chemical isomers. This SPE-IMS-MS platform overcomes many of the current challenges of large-scale metabolomic and exposomic analyses and offers a viable option for population and patient cohort screening in an effort to gain insights into disease processes and human environmental chemical exposure.

SPE-IMS-MS: An automated platform for sub-sixty second surveillance of endogenous metabolites and xenobiotics in biofluids

PubMed Central

Zhang, Xing; Romm, Michelle; Zheng, Xueyun; Zink, Erika M.; Kim, Young-Mo; Burnum-Johnson, Kristin E.; Orton, Daniel J.; Apffel, Alex; Ibrahim, Yehia M.; Monroe, Matthew E.; Moore, Ronald J.; Smith, Jordan N.; Ma, Jian; Renslow, Ryan S.; Thomas, Dennis G.; Blackwell, Anne E.; Swinford, Glenn; Sausen, John; Kurulugama, Ruwan T.; Eno, Nathan; Darland, Ed; Stafford, George; Fjeldsted, John; Metz, Thomas O.; Teeguarden, Justin G.; Smith, Richard D.; Baker, Erin S.

2017-01-01

Characterization of endogenous metabolites and xenobiotics is essential to deconvoluting the genetic and environmental causes of disease. However, surveillance of chemical exposure and disease-related changes in large cohorts requires an analytical platform that offers rapid measurement, high sensitivity, efficient separation, broad dynamic range, and application to an expansive chemical space. Here, we present a novel platform for small molecule analyses that addresses these requirements by combining solid-phase extraction with ion mobility spectrometry and mass spectrometry (SPE-IMS-MS). This platform is capable of performing both targeted and global measurements of endogenous metabolites and xenobiotics in human biofluids with high reproducibility (CV 6 3%), sensitivity (LODs in the pM range in biofluids) and throughput (10-s sample-to-sample duty cycle). We report application of this platform to the analysis of human urine from patients with and without type 1 diabetes, where we observed statistically significant variations in the concentration of disaccharides and previously unreported chemical isomers. This SPE-IMS-MS platform overcomes many of the current challenges of large-scale metabolomic and exposomic analyses and offers a viable option for population and patient cohort screening in an effort to gain insights into disease processes and human environmental chemical exposure. PMID:29276770

3D Groundwater Flow Model in the Arid Region of Tafilalet Oasis System (South East of Morocco)

NASA Astrophysics Data System (ADS)

Bouaamlat, I.; Larabi, A.; Faouzi, M.

2013-05-01

The plain of Tafilalet contains an important oasis located in the Southeast of Morocco in a pre-Saharan area, characterized by an arid climate with a large deficit water budget. It has a behavior of a large depression resulting from erosion of a set of geological coverage during the Quaternary period. It also forms a small Mesopotamia crossed by two main rivers from the mountains of the High Atlas: Ziz and Rheris. The oasis of Tafilalet is an area of old traditions irrigation where agriculture is the main activity of the region that represents approximately 37% of the total area (637 km2). In this study, a three-dimensional model of groundwater flow was developed for the aquifer system of Tafilalet, to assist the decision makers as a "management tool" in order to assess alternative schemes for development and exploitation of groundwater resources in the Tafilalet plain, using Modflow2000 code. It is the first mathematical model performed for this oasis plain, taking into account the most possible real hydrogeological conditions and using the geographical information system (GIS) for the organisation and treatment of data and applying a multidisciplinary approach combining geostatistical and hydrogeological modeling. The conceptual model, in terms of hydrogeological modeling was therefore considered as a monolayer model and the aquifer system is mainly heterogeneous with lateral different hydraulic conductivities, which are ranging from 3.10-7 to 5.10-2 m/s, but most of them are located between 2.10-4 and 8.10-3 m/s. The results of the model calibration under steady state (1960) and transient state conditions, starting from this time, show reasonable agreement between observed and simulated water levels for the observation wells. After calibration, the model contributed to better groundwater characterization, the hydrodynamic parameters obtained from the model are much representative of reality. As a management tool, this model can help the manager to take

The oasis of Tiout in the southwest of Algeria: Water resources and sustainable development

NASA Astrophysics Data System (ADS)

Hadidi, Abdelkader; Remini, Boualem; Habi, Mohamed; Saba, Djamel; Benmedjaed, Milloud

2016-07-01

The Tiout oasis is located in the municipality of Naama at the south west of Algeria is known by their ksour, the palm plantations and the good quality of their fruit and vegetables, in particular the dates and its varieties. This area contains enormous capacities of subsoil and superficial water. For several centuries, domestic consumption and the irrigation are carried out by the use of the traditional techniques of water collecting such as; the pendulum wells and foggaras them. Currently, this hydraulic heritage encounters technical and social problems, in particular with the contribution of drillings and the motor- pumps. The main issues are quoted: • Beating and draining of the water sources; • Degradation and abandonment of the traditional techniques.This study objective is to make an inventory of all the water sources in the study area, to study the impact of the modern technologies contribution on the ancestral techniques and finally to propose recommendations for the backup of the hydraulic heritage.

Chemical Explosion Experiments to Improve Nuclear Test Monitoring [Developing a New Paradigm for Nuclear Test Monitoring with the Source Physics Experiments (SPE)

DOE PAGES

Snelson, Catherine M.; Abbott, Robert E.; Broome, Scott T.; ...

2013-07-02

A series of chemical explosions, called the Source Physics Experiments (SPE), is being conducted under the auspices of the U.S. Department of Energy’s National Nuclear Security Administration (NNSA) to develop a new more physics-based paradigm for nuclear test monitoring. Currently, monitoring relies on semi-empirical models to discriminate explosions from earthquakes and to estimate key parameters such as yield. While these models have been highly successful monitoring established test sites, there is concern that future tests could occur in media and at scale depths of burial outside of our empirical experience. This is highlighted by North Korean tests, which exhibit poormore » performance of a reliable discriminant, mb:Ms (Selby et al., 2012), possibly due to source emplacement and differences in seismic responses for nascent and established test sites. The goal of SPE is to replace these semi-empirical relationships with numerical techniques grounded in a physical basis and thus applicable to any geologic setting or depth.« less

Use of diffusion-ordered NMR spectroscopy and HPLC-UV-SPE-NMR to identify undeclared synthetic drugs in medicines illegally sold as phytotherapies.

PubMed

Silva, Lorena M A; Filho, Elenilson G A; Thomasi, Sérgio S; Silva, Bianca F; Ferreira, Antonio G; Venâncio, Tiago

2013-09-01

The informal (and/or illegal) e-commerce of pharmaceutical formulations causes problems that governmental health agencies find hard to control, one of which concerns formulas sold as natural products. The purpose of this work was to explore the advantages and limitations of DOSY and HPLC-UV-SPE-NMR. These techniques were used to identify the components of a formula illegally marketed in Brazil as an herbal medicine possessing anti-inflammatory and analgesic properties. DOSY was able to detect the major components present at higher concentrations. Complete characterization was achieved using HPLC-UV-SPE-NMR, and 1D and 2D NMR analyses enabled the identification of known synthetic drugs. These were ranitidine and a mixture of orphenadrine citrate, piroxicam, and dexamethasone, which are co-formulated in a remedy called Rheumazim that is used to relieve severe pain, but it is prohibited in Brazil because of a lack of sufficient pharmacokinetic and pharmacodynamic information. Copyright © 2013 John Wiley & Sons, Ltd.

Application of Nanofiber-packed SPE for Determination of Urinary 1-Hydroxypyrene Level Using HPLC.

PubMed

Ifegwu, Okechukwu Clinton; Anyakora, Chimezie; Chigome, Samuel; Torto, Nelson

2014-01-01

It is always desirable to achieve maximum sample clean-up, extraction, and pre-concentration with the minimum possible organic solvent. The miniaturization of sample preparation devices was successfully demonstrated by packing 10 mg of 11 electrospun polymer nanofibers into pipette tip micro column and mini disc cartridges for efficient pre-concentration of 1-hydroxypyrene in urine samples. 1-hydroxypyrene is an extensively studied biomarker of the largest class of chemical carcinogens. Excretory 1-hydroxypyrene was monitored with HPLC/fluorescence detector. Important parameters influencing the percentage recovery such as fiber diameter, fiber packing amount, eluent, fiber packing format, eluent volume, surface area, porosity, and breakthrough parameters were thoroughly studied and optimized. Under optimized condition, there was a near perfect linearity of response in the range of 1-1000 μg/L with a coefficient of determination (r (2)) between 0.9992 and 0.9999 and precision (% RSD) ≤7.64% (n = 6) for all the analysis (10, 25, and 50 μg/L). The Limit of detection (LOD) was between 0.022 and 0.15 μg/L. When compared to the batch studies, both disc packed nanofiber sorbents and pipette tip packed sorbents exhibited evident dominance based on their efficiencies. The experimental results showed comparable absolute recoveries for the mini disc packed fibers (84% for Nylon 6) and micro columns (80% for Nylon 6), although the disc displayed slightly higher recoveries possibly due to the exposure of the analyte to a larger reacting surface. The results also showed highly comparative extraction efficiencies between the nanofibers and conventional C-18 SPE sorbent. Nevertheless, miniaturized SPE devices simplified sample preparation, reducing back pressure, time of the analysis with acceptable reliability, selectivity, detection levels, and environmental friendliness, hence promoting green chemistry.

OASIS: a data and software distribution service for Open Science Grid

NASA Astrophysics Data System (ADS)

Bockelman, B.; Caballero Bejar, J.; De Stefano, J.; Hover, J.; Quick, R.; Teige, S.

2014-06-01

The Open Science Grid encourages the concept of software portability: a user's scientific application should be able to run at as many sites as possible. It is necessary to provide a mechanism for OSG Virtual Organizations to install software at sites. Since its initial release, the OSG Compute Element has provided an application software installation directory to Virtual Organizations, where they can create their own sub-directory, install software into that sub-directory, and have the directory shared on the worker nodes at that site. The current model has shortcomings with regard to permissions, policies, versioning, and the lack of a unified, collective procedure or toolset for deploying software across all sites. Therefore, a new mechanism for data and software distributing is desirable. The architecture for the OSG Application Software Installation Service (OASIS) is a server-client model: the software and data are installed only once in a single place, and are automatically distributed to all client sites simultaneously. Central file distribution offers other advantages, including server-side authentication and authorization, activity records, quota management, data validation and inspection, and well-defined versioning and deletion policies. The architecture, as well as a complete analysis of the current implementation, will be described in this paper.

High-throughput analytical techniques for multiresidue, multiclass determination of 653 pesticides and chemical pollutants in tea--Part III: Evaluation of the cleanup efficiency of an SPE cartridge newly developed for multiresidues in tea.

PubMed

Pang, Guo-Fang; Fan, Chun-Lin; Chang, Qiao-Ying; Li, Yan; Kang, Jian; Wang, Wen-Wen; Cao, Jing; Zhao, Yan-Bing; Li, Nan; Li, Zeng-Yin; Chen, Zong-Mao; Luo, Feng-Jian; Lou, Zheng-Yun

2013-01-01

A comparative study was conducted over three stages on the cleanup efficiency of SPE cartridge Cleanert TPT, newly developed for multigroups of pesticide residues in tea. In Stage I, different SPE cartridges C18, graphite carbon black (GCB), primary secondary amine (PSA), and amino (NH2) were purchased and combined into 12 different sequences. Through the comparative test on cleanup efficiency of 84 representative pesticides in tea, Envi-Carb GCB + PSA with a good cleanup effect was selected. In Stage II, GC/MS test results from the comparative study of the extraction efficiency of 201 pesticides spiked into green tea and Woolong tea with Cleanert TPT and Envi-Carb + PSA SPE showed that average recoveries fell within 70-110% and RSD <20% for 193 and 184 pesticides, respectively, for green tea, accounting for 96.0 and 91.0% of the total number, respectively. GC/MS/MS test results also found 193 and 184 pesticides, respectively, meeting the recovery and RSD conditions, accounting for 96.0 and 91.5%, respectively, of the total number. For Woolong tea samples, GC/MS results showed that with Cleanert TPT and Envi-Carb + PSA SPE for cleanup, there were 192 and 177 pesticides, respectively, meeting the conditions, accounting for 95.5 and 88.1% of the total number, respectively. GC/MS/MS results demonstrated that there were 195 and 184 pesticides, respectively, meeting the conditions, accounting for 97.0 and 91.5% of the total number, respectively. It was seen that Cleanert TPT was superior to Envi-Carb + PSA in cleanup efficiency, whether for green or Woolong tea samples, or GC/MS or GC/MS/MS determination. In Stage III, 61104 results of the average content value of pesticides and RSD (two teas xtwo Youden pair concentrations x two kinds of SPE cartridges x two instruments x 19 tests x 201 pesticides) were derived from the 19 times stability tests over 3 months by paralleling three samples every 5 days via two instruments with two kinds of SPE cartridges for cleanup

HPLC-SPE-NMR identification of a novel metabolite containing the benzo[c]oxepin skeleton from the endophytic fungus Pestalotiopsis virgatula culture.

PubMed

Kesting, Julie R; Staerk, Dan; Tejesvi, Mysore V; Kini, Kukkundoor R; Prakash, Harishchandra S; Jaroszewski, Jerzy W

2009-08-01

HPLC-SPE-NMR analysis of a crude extract of fermentation broth of cultured PESTALOTIOPSIS VIRGATULA isolate TC-320 from TERMINALIA CHEBULA Retz. (Combretaceae) disclosed the presence of a simple but unprecedented low-molecular-weight metabolite, 9-hydroxybenzo[ C]oxepin-3[1 H]-one, subsequently isolated by a targeted purification procedure. Georg Thieme Verlag KG Stuttgart.New York.

Sensitive determination of polycyclic aromatic hydrocarbons in water samples by HPLC coupled with SPE based on graphene functionalized with triethoxysilane.

PubMed

Huang, Ke-Jing; Li, Jing; Liu, Yan-Ming; Wang, Lan

2013-02-01

The graphene functionalized with (3-aminopropyl) triethoxysilane was synthesized by a simple hydrothermal reaction and applied as SPE sorbents to extract trace polycyclic aromatic hydrocarbons (PAHs) from environmental water samples. These sorbents possess high adsorption capacity and extraction efficiency due to strong adsorption ability of carbon materials and large specific surface area of nanoparticles, and only 10 mg of sorbents are required to extract PAHs from 100 mL water samples. Several condition parameters, such as eluent and its volume, adsorbent amount, sample volume, sample pH, and sample flow rate, were optimized to achieve good sensitivity and precision. Under the optimized extraction conditions, the method showed good linearity in the range of 1-100 μg/L, repeatability of the extraction (the RSDs were between 1.8 and 2.9%, n = 6), and satisfactory detection limits of 0.029-0.1 μg/L. The recoveries of PAHs spiked in environmental water samples ranged from 84.6 to 109.5%. All these results demonstrated that this new SPE technique was a viable alternative to conventional enrichment techniques for the extraction and analysis of PAHs in complex samples. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Determination of iodinated X-ray contrast media in sewage by solid-phase extraction and liquid chromatography tandem mass spectrometry.

PubMed

Echeverría, S; Borrull, F; Fontanals, N; Pocurull, E

2013-11-15

A method for the quantitative determination of five iodinated X-ray contrast media (ICMs) in sewage was developed by solid-phase extraction and high-performance liquid chromatography-tandem mass spectrometry. A fused-core analytical column was successfully applied for the first time for the separation of ICMs. Oasis HLB was selected from the sorbents tested because of its higher recoveries. The optimized method allowed the determination of the ICMs at low ng/L levels in both influent and effluent sewage, with detection limits of 40 ng/L and 10 ng/L for most compounds in influent and effluent sewage, respectively. The five ICMs studied were determined in all samples analysed, with iopromide being the analyte found at the highest concentration (8.9 µg/L), while iopamidol was the analyte found at lowest concentration (1.3 µg/L) in influent sewage. Effluent sewage did not show a significant decrease in ICM concentrations. © 2013 Elsevier B.V. All rights reserved.

Liquid chromatographic determination of minocycline in brain-to-plasma distribution studies in the rat.

PubMed

Colovic, Milena; Caccia, Silvio

2003-07-05

An isocratic reversed-phase high-performance liquid chromatographic procedure was developed for the determination of minocycline in rat plasma and brain and applied to brain-to-blood (plasma) distribution studies. The procedure is based on isolation of the compound and the internal standard (either demeclocycline or tetracycline may be used) from plasma and brain constituents using the Oasis HLB cartridge, with satisfactory recovery and specificity, and separation on a Symmetry Shield RP8 (15 cm x 4.6 mm, 3.5 microm) column coupled with a UV detector set at 350 nm. The assay was linear over a wide range, with a lower limit of quantification of 50 ng ml(-1) or g(-1), using 0.2 ml of plasma and about 200 mg of brain tissue. Precision and accuracy were acceptable. In the rat minocycline crossed the blood-brain barrier slowly, achieving mean brain concentrations between 30 and 40% of the equivalent systemic exposure, regardless of the dose and route of administration.

Determination of polychlorinated biphenyls in transformer oil using various adsorbents for solid phase extraction.

PubMed

Na, Yun-Cheol; Kim, Kang-Jin; Hong, Jongki; Seo, Jung-Ju

2008-08-01

Various adsorbents for a solid phase extraction (SPE) method were used to study their ability to separate PCBs from transformer oil to rapidly determine their sub-ppm concentration in the transformer oil. Approximately 90% of the transformer oil could be removed from the PCBs by using a hydrophilic-lipophilic balanced copolymer (HLB) adsorbent, but the recovery of deca-chlorobiphenyl (deca-CB) used as a surrogate was only 24.5% due to lose during this cleanup process. The use of a silica adsorbent gave good results with 89.9% recovery of the deca-CB. The recovery of Aroclor 1242 and 1260 were 95.4 and 90.3% on silica, and 98.9 and 83.5% on HLB, respectively. Acid treatment was an essential step in removing the ambiguous interference peaks to help identify the PCBs. A decreased sensitivity of the electron capture detection (ECD) for PCBs was observed due to the presence of the remaining trace oil after the workup procedure. This loss in sensitivity was allowed for by using tetrachloroxylene as an internal standard, and this was found to be reliable for the criteria of quality control by employing an experiment in which LCS was spiked with 2mg/l of Aroclor 1260 and analyzed each day over a 25 day period. The MDL for the analytical method established in this study is 0.05 mg/l.

Simultaneous determination of PPCPs, EDCs, and artificial sweeteners in environmental water samples using a single-step SPE coupled with HPLC-MS/MS and isotope dilution.

PubMed

Tran, Ngoc Han; Hu, Jiangyong; Ong, Say Leong

2013-09-15

A high-throughput method for the simultaneous determination of 24 pharmaceuticals and personal care products (PPCPs), endocrine disrupting chemicals (EDCs) and artificial sweeteners (ASs) was developed. The method was based on a single-step solid phase extraction (SPE) coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and isotope dilution. In this study, a single-step SPE procedure was optimized for simultaneous extraction of all target analytes. Good recoveries (≥ 70%) were observed for all target analytes when extraction was performed using Chromabond(®) HR-X (500 mg, 6 mL) cartridges under acidic condition (pH 2). HPLC-MS/MS parameters were optimized for the simultaneous analysis of 24 PPCPs, EDCs and ASs in a single injection. Quantification was performed by using 13 isotopically labeled internal standards (ILIS), which allows correcting efficiently the loss of the analytes during SPE procedure, matrix effects during HPLC-MS/MS and fluctuation in MS/MS signal intensity due to instrument. Method quantification limit (MQL) for most of the target analytes was below 10 ng/L in all water samples. The method was successfully applied for the simultaneous determination of PPCPs, EDCs and ASs in raw wastewater, surface water and groundwater samples collected in a local catchment area in Singapore. In conclusion, the developed method provided a valuable tool for investigating the occurrence, behavior, transport, and the fate of PPCPs, EDCs and ASs in the aquatic environment. Copyright © 2013 Elsevier B.V. All rights reserved.

Analysis of some cytokinins in coconut (Cocos nucifera L.) water by micellar electrokinetic capillary chromatography after solid-phase extraction.

PubMed

Ge, Liya; Yong, Jean Wan Hong; Tan, Swee Ngin; Yang, Xin Hao; Ong, Eng Shi

2004-09-03

Micellar electrokinetic capillary chromatography (MECC) was developed for the separation of cytokinins including trans-zeatin, trans-zeatin-O-glucoside, dihydrozeatin, dihydrozeatin-O-glucoside, meta-topolin riboside, N6-isopentenyladenine and N6-benzylaminopurine. Under the optimum conditions, i.e. a combination of 10 mM phosphate and 10 mM borate as the running buffer containing 50 mM sodium dodecyl sulphate at pH 10.4, the separation of seven cytokinin standards was accomplished within 11 min. The C18 solid-phase extraction (SPE) method was used to pre-concentrate the putative cytokinins present in the coconut water. Following which, the eluate was further purified using mixed mode Oasis MCX SPE columns and this additional step helps to reduce matrix interference during MECC. After the two solid-phase extraction steps, the optimized MECC method was able to screen for certain cytokinins (zeatin-O-glucoside and dihydrozeatin-O-glucoside) present in coconut water. After this screening, the presence of zeatin-O-glucoside and dihydrozeatin-O-glucoside in coconut water was further confirmed by independent high-performance liquid chromatography and liquid chromatography-mass spectrometry experiments.

Chemical data and variation diagrams of igneous rocks from the Timber Mountain-Oasis Valley Caldera Complex, southern Nevada

USGS Publications Warehouse

Quinlivan, W.D.; Byers, F.M.

1977-01-01

Silica variation diagrams presented here are based on 162 chemical analyses of tuffs, lavas, and intrusives, representative of volcanic centers of the Timber Mountain-Oasis Valley caldera complex and cogenetic rocks of the Silent Canyon ca1dera. Most of the volcanic units sampled are shown on the U.S. Geological Survey geologic map of the Timber Mountain caldera area (I-891) and are described in U.S. Geological Survey Professional Paper 919. Early effusives of the complex, although slightly altered, are probably chemically, and petrographically, more like the calc-alkalic Fraction Tuff (Miocene) of the northern Nellis Air Force Base Bombing and Gunnery Range to the north, whereas effusives of later Miocene age, such as the Paintbrush and Timber Mountain Tuffs, are alkali-calcic.

Comprehensive non-targeted analysis of contaminated groundwater of a former ammunition destruction site using 1H-NMR and HPLC-SPE-NMR/TOF-MS.

PubMed

Godejohann, Markus; Heintz, Lea; Daolio, Cristina; Berset, Jean-Daniel; Muff, Daniel

2009-09-15

The aim of the present study was to explore the capabilities of the combination of 1H NMR (proton nuclear magnetic resonance) mixture analysis and HPLC-SPE-NMR/TOF-MS (high-performance liquid chromatography coupled to solid-phase extraction and nuclear magnetic resonance and time-of-flight mass spectrometry) for the characterization of xenobiotic contaminants in groundwater samples. As an example, solid-phase extracts of two groundwater samples taken from a former ammunition destruction site in Switzerland were investigated. 1H NMR spectra of postcolumn SPE enriched compounds, together with accurate mass measurements, allowed the structural elucidation of unknowns. This untargeted approach allowed us to identify expected residues of explosives such as 2,4,6-trinitrotoluene (2,4,6-TNT), Hexogen (RDX) and Octogen (HMX), degradation products of TNT (1,3,5-trinitrobenzene (1,3,5-TNB), 2-amino-4,6-dinitrotoluene (2-A-4,6-DNT), 3,5-dinitrophenol (3,5-DNP), 3,5-dinitroaniline (3,5-DNA), 2,6-dinitroanthranite, and 2-Hydroxy-4,6-dinitrobenzonitrile), benzoic acid, Bisphenol A (a known endocrine disruptor compound), and some toxicologically relevant additives for propelling charges: Centralite I (1,3-diethyl-1,3-diphenylurea), DPU (N,N-diphenylurethane), N,N-diphenylcarbamate (Acardite II), and N-methyl-N-phenylurethane. To our knowledge, this is the first report of the presence of these additives in environmental samples. Extraction recoveries for Centralite I and DPU have been determined. Contaminants identified by our techniques were quantified based on HPLC-UV (HPLC-ultraviolet detection) and 1H NMR mixture analysis. The concentrations of the contaminants ranged between 0.1 and 48 microg/L assuming 100% recovery for the SPE step.

Seasonal Change in Titan's Cloud Activity Observed with IRTF/SpeX

NASA Astrophysics Data System (ADS)

Schaller, Emily L.; Brown, M. E.; Roe, H. G.

2006-09-01

We have acquired whole disk spectra of Titan on nineteen nights with IRTF/SpeX over a three-month period in the spring of 2006. The data encompass the spectral range of 0.8 to 2.4 microns at a resolution of 375. These disk-integrated spectra allow us to determine Titan's total fractional cloud coverage and altitudes of clouds present. We find that Titan had less than 0.15% fractional cloud coverage on all but one of the nineteen nights. The near lack of cloud activity in these spectra is in sharp contrast to nearly every spectrum taken from 1995-1999 with UKIRT by Griffith et al. (1998 & 2000) who found rapidly varying clouds covering 0.5% of Titan's disk. The differences in these two similar datasets indicate a striking seasonal change in the behavior of Titan's clouds. Observations of the latitudes, magnitudes, altitudes, and frequencies of Titan's clouds as Titan moves toward southern autumnal equinox in 2009 will help elucidate when and how Titan's methane hydrological cycle changes with season.

Signal processing to evaluate parameters affecting SPE for multi-residue analysis of personal care products.

PubMed

Pietrogrande, Maria Chiara; Basaglia, Giulia; Dondi, Francesco

2009-05-01

This paper discusses the development of a comprehensive method for the simultaneous analysis of personal care products (PCPs) based on SPE and GC-MS. The method was developed on 29 target compounds to represent PCPs belonging to different chemical classes: surfactants in detergents (alkyl benzenes), fragrances in cosmetics (nitro and polycyclic musks), antioxidants and preservatives (phenols), plasticizers (phthalates) displaying a wide range of volatility, polarity, water solubility. In addition to the conventional C(18) stationary phase, a surface modified styrene divinylbenzene polymeric phase (Strata X SPE cartridge) has been investigated as suitable for the simultaneous extraction of several PCPs with polar and non-polar characteristics. For both sorbents different solvent compositions and eluting conditions were tested and compared in order to achieve high extraction efficiency for as many sample components as possible. Comparison of the behavior of the two cartridges reveals that, overall, Strata-X provides better efficiency with extraction recovery higher than 70% for most of the PCPs investigated. The best results were obtained under the following operative conditions: an evaporation temperature of 40 degrees C, elution on Strata-X cartridge using a volume of 15 mL of ethyl acetate (EA) as solvent and operating with slow flow rate (-10 KPa). In addition to the conventional method based on peak integration, a chemometric approach based on the computation of the experimental autocovariance function (EACVF(tot)) was applied to the complex GC-MS signal: the percentage recovery and information on peak abundance distribution can be evaluated for each procedure step. The PC-based signal processing proved very helpful in assisting the development of the analytical procedure, since it saves labor and time and increases result reliability in handling GC complex signals.

Evaluation of OASIS QSAR Models Using ToxCast™ in Vitro Estrogen and Androgen Receptor Binding Data and Application in an Integrated Endocrine Screening Approach

PubMed Central

Bhhatarai, Barun; Wilson, Daniel M.; Price, Paul S.; Marty, Sue; Parks, Amanda K.; Carney, Edward

2016-01-01

Background: Integrative testing strategies (ITSs) for potential endocrine activity can use tiered in silico and in vitro models. Each component of an ITS should be thoroughly assessed. Objectives: We used the data from three in vitro ToxCast™ binding assays to assess OASIS, a quantitative structure-activity relationship (QSAR) platform covering both estrogen receptor (ER) and androgen receptor (AR) binding. For stronger binders (described here as AC50 < 1 μM), we also examined the relationship of QSAR predictions of ER or AR binding to the results from 18 ER and 10 AR transactivation assays, 72 ER-binding reference compounds, and the in vivo uterotrophic assay. Methods: NovaScreen binding assay data for ER (human, bovine, and mouse) and AR (human, chimpanzee, and rat) were used to assess the sensitivity, specificity, concordance, and applicability domain of two OASIS QSAR models. The binding strength relative to the QSAR-predicted binding strength was examined for the ER data. The relationship of QSAR predictions of binding to transactivation- and pathway-based assays, as well as to in vivo uterotrophic responses, was examined. Results: The QSAR models had both high sensitivity (> 75%) and specificity (> 86%) for ER as well as both high sensitivity (92–100%) and specificity (70–81%) for AR. For compounds within the domains of the ER and AR QSAR models that bound with AC50 < 1 μM, the QSAR models accurately predicted the binding for the parent compounds. The parent compounds were active in all transactivation assays where metabolism was incorporated and, except for those compounds known to require metabolism to manifest activity, all assay platforms where metabolism was not incorporated. Compounds in-domain and predicted to bind by the ER QSAR model that were positive in ToxCast™ ER binding at AC50 < 1 μM were active in the uterotrophic assay. Conclusions: We used the extensive ToxCast™ HTS binding data set to show that OASIS ER and AR QSAR models had

A multiscale dataset for understanding complex eco-hydrological processes in a heterogeneous oasis system

PubMed Central

Li, Xin; Liu, Shaomin; Xiao, Qin; Ma, Mingguo; Jin, Rui; Che, Tao; Wang, Weizhen; Hu, Xiaoli; Xu, Ziwei; Wen, Jianguang; Wang, Liangxu

2017-01-01

We introduce a multiscale dataset obtained from Heihe Watershed Allied Telemetry Experimental Research (HiWATER) in an oasis-desert area in 2012. Upscaling of eco-hydrological processes on a heterogeneous surface is a grand challenge. Progress in this field is hindered by the poor availability of multiscale observations. HiWATER is an experiment designed to address this challenge through instrumentation on hierarchically nested scales to obtain multiscale and multidisciplinary data. The HiWATER observation system consists of a flux observation matrix of eddy covariance towers, large aperture scintillometers, and automatic meteorological stations; an eco-hydrological sensor network of soil moisture and leaf area index; hyper-resolution airborne remote sensing using LiDAR, imaging spectrometer, multi-angle thermal imager, and L-band microwave radiometer; and synchronical ground measurements of vegetation dynamics, and photosynthesis processes. All observational data were carefully quality controlled throughout sensor calibration, data collection, data processing, and datasets generation. The data are freely available at figshare and the Cold and Arid Regions Science Data Centre. The data should be useful for elucidating multiscale eco-hydrological processes and developing upscaling methods. PMID:28654086

[Dynamics of ecological footprints of agricultural region in Hexi oasis of Gansu Province].

PubMed

Lin, Haiming; Xie, Peng

2004-05-01

This paper studied the dynamics of ecological footprints (EF), degree of sustainable development and its tendency of Hexi oasis agricultural region in Gansu. The results showed that the EF displayed an increasing trend from 0.426 hm2 to 2.158 hm2 in 1949-2000, which was 0.693 hm2 in 1949-1970, 1.029 hm2 in 1975-1980, and 2.288 hm2 in 1985-2000. The ecological capacity (EC) was also increased from 0.550 hm2 in 1949 to 1.762 hm2 in 2000. Comparing with EF, the EC increased at low speed, which reached 0.782 hm2 in 1949-1970 and 1.715 hm2 in 1975-2000. Meanwhile, the sustainable development of Hexi region maintained ecological remainder during 1949-1975. However, it emerged ecological deficit in 1980, and resumed in 1985. The sustainable development of Hexi region has been successive ecological deficit since 1991. The degree was keeping negative increment at acceleration, and got to -0258 hm2 in 1991-2000. These results showed that the regional economic development of Hexi region was far away from sustainable development, and was in no-sustainable state.

Experimental design for TBT quantification by isotope dilution SPE-GC-ICP-MS under the European water framework directive.

PubMed

Alasonati, Enrica; Fabbri, Barbara; Fettig, Ina; Yardin, Catherine; Del Castillo Busto, Maria Estela; Richter, Janine; Philipp, Rosemarie; Fisicaro, Paola

2015-03-01

In Europe the maximum allowable concentration for tributyltin (TBT) compounds in surface water has been regulated by the water framework directive (WFD) and daughter directive that impose a limit of 0.2 ng L(-1) in whole water (as tributyltin cation). Despite the large number of different methodologies for the quantification of organotin species developed in the last two decades, standardised analytical methods at required concentration level do not exist. TBT quantification at picogram level requires efficient and accurate sample preparation and preconcentration, and maximum care to avoid blank contamination. To meet the WFD requirement, a method for the quantification of TBT in mineral water at environmental quality standard (EQS) level, based on solid phase extraction (SPE), was developed and optimised. The quantification was done using species-specific isotope dilution (SSID) followed by gas chromatography (GC) coupled to inductively coupled plasma mass spectrometry (ICP-MS). The analytical process was optimised using a design of experiment (DOE) based on a factorial fractionary plan. The DOE allowed to evaluate 3 qualitative factors (type of stationary phase and eluent, phase mass and eluent volume, pH and analyte ethylation procedure) for a total of 13 levels studied, and a sample volume in the range of 250-1000 mL. Four different models fitting the results were defined and evaluated with statistic tools: one of them was selected and optimised to find the best procedural conditions. C18 phase was found to be the best stationary phase for SPE experiments. The 4 solvents tested with C18, the pH and ethylation conditions, the mass of the phases, the volume of the eluents and the sample volume can all be optimal, but depending on their respective combination. For that reason, the equation of the model conceived in this work is a useful decisional tool for the planning of experiments, because it can be applied to predict the TBT mass fraction recovery when the

Modeling Elastic Wave Propagation from an Underground Chemical Explosion Using Higher Order Finite Difference Approximation: Theory, Validation and Application to SPE

NASA Astrophysics Data System (ADS)

Hirakawa, E. T.; Ezzedine, S. M.; Petersson, A.; Sjogreen, B.; Vorobiev, O.; Pitarka, A.; Antoun, T.; Walter, W. R.

2016-12-01

Motions from underground explosions are governed by non-linear hydrodynamic response of material. However, the numerical calculation of this non-linear constitutive behavior is computationally intensive in contrast to the elastic and acoustic linear wave propagation solvers. Here, we develop a hybrid modeling approach with one-way hydrodynamic-to-elastic coupling in three dimensions in order to propagate explosion generated ground motions from the non-linear near-source region to the far-field. Near source motions are computed using GEODYN-L, a Lagrangian hydrodynamics code for high-energy loading of earth materials. Motions on a dense grid of points sampled on two nested shells located beyond the non-linear damaged zone are saved, and then passed to SW4, an anelastic anisotropic fourth order finite difference code for seismic wave modeling. Our coupling strategy is based on the decomposition and uniqueness theorems where motions are introduced into SW4 as a boundary source and continue to propagate as elastic waves at a much lower computational cost than by using GEODYN-L to cover the entire near- and the far-field domain. The accuracy of the numerical calculations and the coupling strategy is demonstrated in cases with a purely elastic medium as well as non-linear medium. Our hybrid modeling approach is applied to SPE-4' and SPE-5 which are the most recent underground chemical explosions conducted at the Nevada National Security Site (NNSS) where the Source Physics Experiments (SPE) are performed. Our strategy by design is capable of incorporating complex non-linear effects near the source as well as volumetric and topographic material heterogeneity along the propagation path to receiver, and provides new prospects for modeling and understanding explosion generated seismic waveforms. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-698608.

Development and optimization of SPE-HPLC-UV/ELSD for simultaneous determination of nine bioactive components in Shenqi Fuzheng Injection based on Quality by Design principles.

PubMed

Wang, Lu; Qu, Haibin

2016-03-01

A method combining solid phase extraction, high performance liquid chromatography, and ultraviolet/evaporative light scattering detection (SPE-HPLC-UV/ELSD) was developed according to Quality by Design (QbD) principles and used to assay nine bioactive compounds within a botanical drug, Shenqi Fuzheng Injection. Risk assessment and a Plackett-Burman design were utilized to evaluate the impact of 11 factors on the resolutions and signal-to-noise of chromatographic peaks. Multiple regression and Pareto ranking analysis indicated that the sorbent mass, sample volume, flow rate, column temperature, evaporator temperature, and gas flow rate were statistically significant (p < 0.05) in this procedure. Furthermore, a Box-Behnken design combined with response surface analysis was employed to study the relationships between the quality of SPE-HPLC-UV/ELSD analysis and four significant factors, i.e., flow rate, column temperature, evaporator temperature, and gas flow rate. An analytical design space of SPE-HPLC-UV/ELSD was then constructed by calculated Monte Carlo probability. In the presented approach, the operating parameters of sample preparation, chromatographic separation, and compound detection were investigated simultaneously. Eight terms of method validation, i.e., system-suitability tests, method robustness/ruggedness, sensitivity, precision, repeatability, linearity, accuracy, and stability, were accomplished at a selected working point. These results revealed that the QbD principles were suitable in the development of analytical procedures for samples in complex matrices. Meanwhile, the analytical quality and method robustness were validated by the analytical design space. The presented strategy provides a tutorial on the development of a robust QbD-compliant quantitative method for samples in complex matrices.

Determination of Benzo[α]pyrene in Edible Oil Using Tetraoxocalix[2]arene[2]triazine Bonded Silica SPE Sorbent.

PubMed

Guo, Yun; Zhao, Wen-Jie; Deng, Zhi-Fen; Hongbo, Wang; Peng, Bin; Ma, Xue; Lan, Chen; Zhang, Shu-Sheng

2018-06-01

Benzo[α]pyrene (BaP) is a well-known carcinogen in edible oil. In this study, a method combined solid-phase extraction (SPE) with fluorescent detection was developed using tetraoxocalix[2]arene[2]triazine sorbent (SiO 2 -OCA) for the clean-up and enrichment of BaP. The interaction between SiO 2 -OCA and BaP involves a donor-acceptor complex mechanism. The experimental procedure was as follows: BaP was extracted from edible oil with DMF/H 2 O (9:1, v/v). Then, the ratio of DMF/H 2 O was adjusted to 1:2 prior to SPE. The final concentrate was analyzed using a fluorescence detector at excitation and emission wavelengths of 255 and 420 nm. The method was fully validated. The linearity was in the range of 0.1-100 μg kg -1 with a coefficient of 0.999. The limits of detection and quantification were 0.03 and 0.1 μg kg -1 , respectively. The average recoveries were in the range of 88.0-122.3%. The intraday and interday precisions were 6.8% and 9.2%, respectively. Compared with other methods, the method reported in this article shows a good detection limit, high reproducibility and recovery, and linearity over a broad concentration range. This established method was also applied to evaluate real samples. The concentration of six tested samples was below 5 μg kg -1 .

A Compact Laboratory Spectro-Goniometer (CLabSpeG) to Assess the BRDF of Materials. Presentation, Calibration and Implementation on Fagus sylvatica L. Leaves

PubMed Central

Biliouris, Dimitrios; Verstraeten, Willem W.; Dutré, Phillip; van Aardt, Jan A.N.; Muys, Bart; Coppin, Pol

2007-01-01

The design and calibration of a new hyperspectral Compact Laboratory Spectro-Goniometer (CLabSpeG) is presented. CLabSpeG effectively measures the bidirectional reflectance Factor (BRF) of a sample, using a halogen light source and an Analytical Spectral Devices (ASD) spectroradiometer. The apparatus collects 4356 reflectance data readings covering the spectrum from 350 nm to 2500 nm by independent positioning of the sensor, sample holder, and light source. It has an azimuth and zenith resolution of 30 and 15 degrees, respectively. CLabSpeG is used to collect BRF data and extract Bidirectional Reflectance Distribution Function (BRDF) data of non-isotropic vegetation elements such as bark, soil, and leaves. Accurate calibration has ensured robust geometric accuracy of the apparatus, correction for the conicality of the light source, while sufficient radiometric stability and repeatability between measurements are obtained. The bidirectional reflectance data collection is automated and remotely controlled and takes approximately two and half hours for a BRF measurement cycle over a full hemisphere with 125 cm radius and 2.4 minutes for a single BRF acquisition. A specific protocol for vegetative leaf collection and measurement was established in order to investigate the possibility to extract BRDF values from Fagus sylvatica L. leaves under laboratory conditions. Drying leaf effects induce a reflectance change during the BRF measurements due to the laboratory illumination source. Therefore, the full hemisphere could not be covered with one leaf. Instead 12 BRF measurements per leaf were acquired covering all azimuth positions for a single light source zenith position. Data are collected in radiance format and reflectance is calculated by dividing the leaf cycle measurement with a radiance cycle of a Spectralon reference panel, multiplied by a Spectralon reflectance correction factor and a factor to correct for the conical effect of the light source. BRF results of

A Compact Laboratory Spectro-Goniometer (CLabSpeG) to Assess the BRDF of Materials. Presentation, Calibration and Implementation on Fagus sylvatica L. Leaves.

PubMed

Biliouris, Dimitrios; Verstraeten, Willem W; Dutré, Phillip; Van Aardt, Jan A N; Muys, Bart; Coppin, Pol

2007-09-07

The design and calibration of a new hyperspectral Compact Laboratory Spectro-Goniometer (CLabSpeG) is presented. CLabSpeG effectively measures the bidirectionalreflectance Factor (BRF) of a sample, using a halogen light source and an AnalyticalSpectral Devices (ASD) spectroradiometer. The apparatus collects 4356 reflectance datareadings covering the spectrum from 350 nm to 2500 nm by independent positioning of thesensor, sample holder, and light source. It has an azimuth and zenith resolution of 30 and15 degrees, respectively. CLabSpeG is used to collect BRF data and extract BidirectionalReflectance Distribution Function (BRDF) data of non-isotropic vegetation elements suchas bark, soil, and leaves. Accurate calibration has ensured robust geometric accuracy of theapparatus, correction for the conicality of the light source, while sufficient radiometricstability and repeatability between measurements are obtained. The bidirectionalreflectance data collection is automated and remotely controlled and takes approximatelytwo and half hours for a BRF measurement cycle over a full hemisphere with 125 cmradius and 2.4 minutes for a single BRF acquisition. A specific protocol for vegetative leafcollection and measurement was established in order to investigate the possibility to extractBRDF values from Fagus sylvatica L. leaves under laboratory conditions. Drying leafeffects induce a reflectance change during the BRF measurements due to the laboratorySensors 2007, 7 1847 illumination source. Therefore, the full hemisphere could not be covered with one leaf. Instead 12 BRF measurements per leaf were acquired covering all azimuth positions for a single light source zenith position. Data are collected in radiance format and reflectance is calculated by dividing the leaf cycle measurement with a radiance cycle of a Spectralon reference panel, multiplied by a Spectralon reflectance correction factor and a factor to correct for the conical effect of the light source. BRF results

Comparison of the sampling rates and partitioning behaviour of polar and non-polar contaminants in the polar organic chemical integrative sampler and a monophasic mixed polymer sampler for application as an equilibrium passive sampler.

PubMed

Jeong, Yoonah; Schäffer, Andreas; Smith, Kilian

2018-06-15

In this work, Oasis HLB® beads were embedded in a silicone matrix to make a single phase passive sampler with a higher affinity for polar and ionisable compounds than silicone alone. The applicability of this mixed polymer sampler (MPS) was investigated for 34 aquatic contaminants (log K OW -0.03 to 6.26) in batch experiments. The influence of flow was investigated by comparing uptake under static and stirred conditions. The sampler characteristics of the MPS was assessed in terms of sampling rates (R S ) and sampler-water partition coefficients (K SW ), and these were compared to those of the polar organic chemical integrative sampler (POCIS) as a reference kinetic passive sampler. The MPS was characterized as an equilibrium sampler for both polar and non-polar compounds, with faster uptake rates and a shorter time to reach equilibrium than the POCIS. Water flow rate impacted sampling rates by up to a factor of 12 when comparing static and stirred conditions. In addition, the relative accumulation of compounds in the polyethersulfone (PES) membranes versus the inner Oasis HLB sorbent was compared for the POCIS, and ranged from <1% to 83% depending on the analyte properties. This is indicative of a potentially significant lag-phase for less polar compounds within POCIS. The findings of this study can be used to quantitatively describe the partitioning and kinetic behaviour of MPS and POCIS for a range of aquatic organic contaminants for application in field sampling. Copyright © 2018 Elsevier B.V. All rights reserved.

Urine Multi-drug Screening with GC-MS or LC-MS-MS Using SALLE-hybrid PPT/SPE.

PubMed

Lee, Junhui; Park, Jiwon; Go, Ahra; Moon, Heesung; Kim, Sujin; Jung, Sohee; Jeong, Wonjoon; Chung, Heesun

2018-05-14

To intoxicated patients in the emergency room, toxicological analysis can be considerably helpful for identifying the involved toxicants. In order to develop a urine multi-drug screening (UmDS) method, gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) were used to determine targeted and unknown toxicants in urine. A GC-MS method in scan mode was validated for selectivity, limit of detection (LOD) and recovery. An LC-MS-MS multiple reaction monitoring (MRM) method was validated for lower LOD, recovery and matrix effect. The results of the screening analysis were compared with patient medical records to check the reliability of the screen. Urine samples collected from an emergency room were extracted through a combination of salting-out assisted liquid-liquid extraction (SALLE) and hybrid protein precipitation/solid phase extraction (hybrid PPT/SPE) plates and examined by GC-MS and LC-MS-MS. GC-MS analysis was performed as unknown drug screen and LC-MS-MS analysis was conducted as targeted drug screen. After analysis by GC-MS, a library search was conducted using an in-house library established with the automated mass spectral deconvolution and identification system (AMDISTM). LC-MS-MS used Cliquid®2.0 software for data processing and acquisition in MRM mode. An UmDS method by GC-MS and LC-MS-MS was developed by using a SALLE-hybrid PPT/SPE and in-house library. The results of UmDS by GC-MS and LC-MS-MS showed that toxicants could be identified from 185 emergency room patient samples containing unknown toxicants. Zolpidem, acetaminophen and citalopram were the most frequently encountered drugs in emergency room patients. The UmDS analysis developed in this study can be used effectively to detect toxic substances in a short time. Hence, it could be utilized in clinical and forensic toxicology practices.

An optimized method for the accurate determination of patulin in apple products by isotope dilution-liquid chromatography/mass spectrometry.

PubMed

Seo, Miyeong; Kim, Byungjoo; Baek, Song-Yee

2015-07-01

Patulin, a mycotoxin produced by several molds in fruits, has been frequently detected in apple products. Therefore, regulatory bodies have established recommended maximum permitted patulin concentrations for each type of apple product. Although several analytical methods have been adopted to determine patulin in food, quality control of patulin analysis is not easy, as reliable certified reference materials (CRMs) are not available. In this study, as a part of a project for developing CRMs for patulin analysis, we developed isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC/MS/MS) as a higher-order reference method for the accurate value-assignment of CRMs. (13)C7-patulin was used as internal standard. Samples were extracted with ethyl acetate to improve recovery. For further sample cleanup with solid-phase extraction (SPE), the HLB SPE cartridge was chosen after comparing with several other types of SPE cartridges. High-performance liquid chromatography was performed on a multimode column for proper retention and separation of highly polar and water-soluble patulin from sample interferences. Sample extracts were analyzed by LC/MS/MS with electrospray ionization in negative ion mode with selected reaction monitoring of patulin and (13)C7-patulin at m/z 153→m/z 109 and m/z 160→m/z 115, respectively. The validity of the method was tested by measuring gravimetrically fortified samples of various apple products. In addition, the repeatability and the reproducibility of the method were tested to evaluate the performance of the method. The method was shown to provide accurate measurements in the 3-40 μg/kg range with a relative expanded uncertainty of around 1%.

Isolation and molecular identification of Acanthamoeba spp from oasis water in Tunisia.

PubMed

Dendana, F; Trabelsi, H; Neiji, S; Sellami, H; Kammoun, S; Makni, F; Feki, J; Cheikhrouhou, F; Ayadi, A

2018-04-01

In the southern Tunisia Oasis, we conducted 211 water with drawals from various water traffic sites. This water is used for agriculture, swimming or various other human activities. Acanthamoeba genus was detected in 82% of collected samples. Sequencing of the amplification products with primers P892C/P892 has allowed us to detect genotypic variation with predominance of T4 genotype (51%) and presence of the genotypes T14, T5, T3, T16, T15, T10, T11, T9 and T7. They T4, T3, T5, T15, T11 and T10 genotypes have a high potential for pathogenicity and a very high degree of virulence due to their production of serine proteases and extracellular cysteine enzymes involved in tissue degradation of the host. T4 genotype was the most abundant in the environment as well as in infections caused by Acanthamoeba spp. T5 genotype was ranked second and T3 genotype was less abundant in the environment and its pathogenicity is discussed. Acanthamoeba strains with the genotypes T16, T9 and T7 were considered non pathogenic. In fact, they have been isolated only from the environment. However, for these strains, their role as a reservoir can be a real risk to human health. Copyright © 2018. Published by Elsevier Inc.

The critical role of local policy effects in arid watershed groundwater resources sustainability: A case study in the Minqin oasis, China.

PubMed

Hao, Yuanyuan; Xie, Yaowen; Ma, Jinhui; Zhang, Wenpei

2017-12-01

Designed as a watershed groundwater restoration policy (WGRP), the Comprehensive Treatment Program of the Shiyang River Basin (CTSRB) was launched in 2006 to restore the groundwater resources in the Minqin oasis, northwestern China. This study sought to verify the recovery effects of CTSRB implementation from the perspective of groundwater depth. We reconstructed the spatio-temporal distribution of groundwater depth at interannual and pixel scales by using digital groundwater depth models (DGDMs), based on the ordinary kriging interpolation method. Using DGDMs data, various measures of the groundwater table (e.g., regional depths, surface areas, depletion cones, and conditions in irrigated regions including Ba, Quanshan, and Hu) were quantitatively analyzed and compared for the pre-CTSRB (2001-2006), CTSRB I (2006-2010), and CTSRB II (2010-2015) periods, for which spatial trends in the annual amplitudes of groundwater depth were compared. Finally, strategies that impacted the groundwater behavior before and during the CTSRB periods, possible indirect and adverse effects, and long-term strategies and prospects were discussed. The results showed that groundwater depth first declined sharply, before increasing slowly and stabilizing after implementation of the CTSRB. Areas of greater groundwater depth (<-20m) and four groundwater depletion cones expanded during the pre-CTSRB period, whereas variable shrinking trends were detected during the CTSRB period. Spatial analysis showed that groundwater recovery mainly occurred along the periphery of the three irrigated regions, among which recovery effects in Hu were more obvious than those in Quanshan and Ba, with pumping-well densities the main reason for the difference. Therefore, various strategies (increasing the surface water supply, reducing groundwater mining, and some other auxiliary measures) of CTSRB together supported groundwater recovery in the Minqin oasis. Overall, this research demonstrates an innovative

Solid-phase extraction of galloyl- and caffeoylquinic acids from natural sources (Galphimia glauca and Arnicae flos) using pure zirconium silicate and bismuth citrate powders as sorbents inside micro spin columns.

PubMed

Hussain, Shah; Schönbichler, Stefan A; Güzel, Yüksel; Sonderegger, Harald; Abel, Gudrun; Rainer, Matthias; Huck, Christian W; Bonn, Günther K

2013-10-01

Galloyl- and caffeoylquinic acids are among the most important pharmacological active groups of natural compounds. This study describes a pre-step in isolation of some selected representatives of these groups from biological samples. A selective solid-phase extraction (SPE) method for these compounds may help assign classes and isomer designations within complex mixtures. Pure zirconium silicate and bismuth citrate powders (325 mesh) were employed as two new sorbents for optimized SPE of phenolic acids. These sorbents possess electrostatic interaction sites which accounts for additional interactions for carbon acid moieties as compared to hydrophilic and hydrophobic sorbents alone. Based on this principle, a selective SPE method for 1,3,4,5-tetragalloylquinic acid (an anti-HIV and anti-asthamatic agent) as a starting compound was developed and then deployed upon other phenolic acids with success. The recoveries and selectivities of both sorbents were compared to most commonly applied and commercially available sorbents by using high performance liquid chromatography. The nature of interaction between the carrier sorbent and the acidic target molecules was investigated by studying hydrophilic (silica), hydrophobic (C18), mixed-mode (ionic and hydrophobic: Oasis(®) MAX) and predominantly electrostatic (zirconium silicate) materials. The newly developed zirconium silicate and bismuth citrate stationary phases revealed promising results for the selective extraction of galloyl- and caffeoylquinic acids from natural sources. It was observed that zirconium silicate exhibited maximum recovery and selectivity for tetragalloylquinic acid (84%), chlorogenic acid (82%) and dicaffeoylquinic acid (94%) among all the tested sorbents. Copyright © 2013 Elsevier B.V. All rights reserved.

Analysis of amphetamine and methamphetamine in municipal wastewater influent and effluent using weak cation-exchange SPE and LC-MS/MS.

PubMed

Boles, Tammy H; Wells, Martha J M

2016-12-01

Amphetamine and methamphetamine are emerging contaminants-those for which no regulations currently require monitoring or public reporting of their presence in our water supply. In this research, a protocol for weak cation-exchange (WCX) SPE coupled with LC-MS/MS was developed for determination of emerging contaminants amphetamine and methamphetamine in a complex wastewater matrix. Gradient LC parameters were adjusted to yield baseline separation of methamphetamine from other contaminants. Methamphetamine-D5 was used as the internal standard (IS) to compensate for sample loss during SPE and for signal loss during MS (matrix effects). Recoveries were 102.1 ± 7.9% and 99.4 ± 4.0% for amphetamine and methamphetamine, respectively, using WCX sorbent. Notably, methamphetamine was determined to be present in wastewater influent at each sampling date tested. Amphetamine was present in wastewater influent on two of four sampling dates. Amphetamine concentrations ranged from undetectable to 86.4 ng/L in influent, but it was undetectable in wastewater effluent. Methamphetamine was detected in influent at concentrations ranging from 27.0-60.3 ng/L. Methamphetamine concentration was reduced but incompletely removed at this facility. Although absent in one post-UV effluent sample, concentrations of methamphetamine ranged from 10.8-14.8 ng/L. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Automated Solid Phase Extraction (SPE) LC/NMR Applied to the Structural Analysis of Extractable Compounds from a Pharmaceutical Packaging Material of Construction.

PubMed

Norwood, Daniel L; Mullis, James O; Davis, Mark; Pennino, Scott; Egert, Thomas; Gonnella, Nina C

2013-01-01

The structural analysis (i.e., identification) of organic chemical entities leached into drug product formulations has traditionally been accomplished with techniques involving the combination of chromatography with mass spectrometry. These include gas chromatography/mass spectrometry (GC/MS) for volatile and semi-volatile compounds, and various forms of liquid chromatography/mass spectrometry (LC/MS or HPLC/MS) for semi-volatile and relatively non-volatile compounds. GC/MS and LC/MS techniques are complementary for structural analysis of leachables and potentially leachable organic compounds produced via laboratory extraction of pharmaceutical container closure/delivery system components and corresponding materials of construction. Both hyphenated analytical techniques possess the separating capability, compound specific detection attributes, and sensitivity required to effectively analyze complex mixtures of trace level organic compounds. However, hyphenated techniques based on mass spectrometry are limited by the inability to determine complete bond connectivity, the inability to distinguish between many types of structural isomers, and the inability to unambiguously determine aromatic substitution patterns. Nuclear magnetic resonance spectroscopy (NMR) does not have these limitations; hence it can serve as a complement to mass spectrometry. However, NMR technology is inherently insensitive and its ability to interface with chromatography has been historically challenging. This article describes the application of NMR coupled with liquid chromatography and automated solid phase extraction (SPE-LC/NMR) to the structural analysis of extractable organic compounds from a pharmaceutical packaging material of construction. The SPE-LC/NMR technology combined with micro-cryoprobe technology afforded the sensitivity and sample mass required for full structure elucidation. Optimization of the SPE-LC/NMR analytical method was achieved using a series of model compounds

Paleo-oncology in the Dakhleh Oasis, Egypt: Case studies and a paleoepidemiological perspective.

PubMed

Molto, El; Sheldrick, Peter

2018-06-01

This article describes six cases of cancer from the Dakhleh Oasis, Egypt. A mummy had a confirmed 'primary' diagnosis of adenocarcinoma of the rectum. The remaining diagnoses were based on the distribution and types of skeletal lesions in conjunction with age, sex, and/or the molecular phylogeny of the Human Papillomavirus (HPV). HPV is a confirmed cause of cancer of the uterine cervix (UC) and testes (TC) and it evolved in Africa long before Homo sapiens emerged. Today these cancers are common in young adult females and males, a fact which was pivotal in respectively including them in the differential diagnosis of UC and TC. The remaining diagnoses were acute lymphocytic leukemia in a 3-5 year old child and an older female with metastatic carcinoma. Due to problems of determining specific diagnoses and their prevalence in 'paleo' populations, we opted for a lifetime cancer risk statistic (LTCR). The LTCR in ancient Dakhleh was ∼5/1000 (6/1087). In modern Western societies the LTCR cancer approaches 50% (500/1000). Thus the LTCR in today's western societies is 100 times greater than in ancient Dakhleh. These cases demonstrate that oncogenes and their environmental cofactors were present in antiquity, but were significantly less pervasive than today. Copyright © 2018. Published by Elsevier Inc.

Coupling HPLC-SPE-NMR with a microplate-based high-resolution antioxidant assay for efficient analysis of antioxidants in food--validation and proof-of-concept study with caper buds.

PubMed

Wiese, Stefanie; Wubshet, Sileshi G; Nielsen, John; Staerk, Dan

2013-12-15

This work describes the coupling of a microplate-based antioxidant assay with a hyphenated system consisting of high-performance liquid chromatography-solid-phase extraction-nuclear magnetic resonance spectroscopy, i.e., HPLC-SPE-NMR/high-resolution antioxidant assay, for the analysis of complex food extracts. The applicability of the microplate-based antioxidant assay for high-resolution screening of common food phenolics as well as parameters related to their trapping efficiency, elution behavior, and recovery on/from SPE cartridges are described. It was found that the microplate-based high-resolution antioxidant assay is an attractive and easy implementable alternative to direct on-line screening methods. Furthermore, it was shown that Resin SH and Resin GP SPE material are superior to RP C18HD for trapping of phenolic compounds. Proof-of-concept study was performed with caper bud extract, revealing the most important antioxidants to be quercetin, kaempferol, rutin, kaempferol-3-O-β-rutinoside and N(1),N(5),N(10)-triphenylpropenoyl spermidine amides. Targeted isolation of the latter, and comprehensive NMR experiments showed them to be N(1),N(10)-di-(E)-caffeoyl-N(5)-p-(E)-coumaroyl spermidine, N(1)-(E)-caffeoyl-N(5),N(10)-di-p-(E)-coumaroyl spermidine, N(10)-(E)-caffeoyl-N(1),N(5)-di-p-(E)-coumaroyl spermidine, and N(1),N(5),N(10)-tri-p-(E)-coumaroyl spermidine amides. Copyright © 2013 Elsevier Ltd. All rights reserved.

High-throughput hydrophilic interaction chromatography coupled to tandem mass spectrometry for the optimized quantification of the anti-Gram-negatives antibiotic colistin A/B and its pro-drug colistimethate.

PubMed

Mercier, Thomas; Tissot, Fréderic; Gardiol, Céline; Corti, Natascia; Wehrli, Stéphane; Guidi, Monia; Csajka, Chantal; Buclin, Thierry; Couet, William; Marchetti, Oscar; Decosterd, Laurent A

2014-11-21

Colistin is a last resort's antibacterial treatment in critically ill patients with multi-drug resistant Gram-negative infections. As appropriate colistin exposure is the key for maximizing efficacy while minimizing toxicity, individualized dosing optimization guided by therapeutic drug monitoring is a top clinical priority. Objective of the present work was to develop a rapid and robust HPLC-MS/MS assay for quantification of colistin plasma concentrations. This novel methodology validated according to international standards simultaneously quantifies the microbiologically active compounds colistin A and B, plus the pro-drug colistin methanesulfonate (colistimethate, CMS). 96-well micro-Elution SPE on Oasis Hydrophilic-Lipophilic-Balanced (HLB) followed by direct analysis by Hydrophilic Interaction Liquid Chromatography (HILIC) with Ethylene Bridged Hybrid--BEH--Amide phase column coupled to tandem mass spectrometry allows a high-throughput with no significant matrix effect. The technique is highly sensitive (limit of quantification 0.014 and 0.006 μg/mL for colistin A and B), precise (intra-/inter-assay CV 0.6-8.4%) and accurate (intra-/inter-assay deviation from nominal concentrations -4.4 to +6.3%) over the clinically relevant analytical range 0.05-20 μg/mL. Colistin A and B in plasma and whole blood samples are reliably quantified over 48 h at room temperature and at +4°C (<6% deviation from nominal values) and after three freeze-thaw cycles. Colistimethate acidic hydrolysis (1M H2SO4) to colistin A and B in plasma was completed in vitro after 15 min of sonication while the pro-drug hydrolyzed spontaneously in plasma ex vivo after 4 h at room temperature: this information is of utmost importance for interpretation of analytical results. Quantification is precise and accurate when using serum, citrated or EDTA plasma as biological matrix, while use of heparin plasma is not appropriate. This new analytical technique providing optimized quantification in real

Investigation of the superconducting proximity effect (SPE) and magnetic dead layers (MDL) in thin film double layers

NASA Astrophysics Data System (ADS)

Tateishi, Go

When a thin superconducting film (S film) is condensed onto a thin normal conducting film (N film), the first layers of the S film loose their superconductivity. This phenomenon is generally called the "superconducting proximity effect (SPE)". As an investigation of SPE we focus on the transition temperature of extremely thin NS double layers in the thin regime. Normal metal is condensed on top of insulating Sb, then Pb is deposited on it in small steps. The transition temperature is plotted in an inverse Tc-reduction 1/Delta T c =1/(Ts - Tc) versus Pb thickness graph. To compare our experimental results with the theoretical prediction, a numerical calculation of the SN double layer is performed by our group using the linear gap equation. As a result, there are large discrepancies between the experimental and theoretical results generally. The results of the NS double layers can be divided into three groups in terms of their discrepancies between experiment and theory.(1) Non-coupling (Tc = 0 K): N= Mg, Ag, Cu, Au. There are large deviations between experiment and theory by a factor to the order of 2.5. (2) Weak coupling (Tc is low (< 2.5 K)) : N=Cd, Zn, Al. Deviation is present, but only by a factor of 1.5. (3) Intermediate coupling (T c is around half of Pb's (≈ 4.5 K)) : N=In, Sn. The experimental results agree with the theory. Next, we examine the detection of the magnetic dead layer (MDL) of Ni thin films in terms of the anomalous Hall effect (AHE) with several non-magnetic metal substrates. In our results, when Ni film is contact with a polyvalent metal substrate film, the sandwich film has around 2 to 3.5 at.lay. of magnetic dead layers. However we have not observed the magnetic dead Ni layers with the alkali and noble metal substrate film. Finally, we revisit the Pb/Ni system to measure the magnetic scattering of Ni with the method of Weak Localization (WL) to compare with the dephasing rate due to the Tc-reduction. In this series, we use only very thin

The Source Physics Experiments (SPE): A Physics-Based Approach to Discriminate Low-Yield Nuclear Events (Invited)

NASA Astrophysics Data System (ADS)

Snelson, C. M.; Chipman, V.; White, R. L.; Emmitt, R.; Townsend, M.

2013-12-01

Discriminating low-yield nuclear explosions is one of the current challenges in the field of monitoring and verification. Work is currently underway in Nevada to address this challenge by conducting a series of experiments using a physics-based approach. This has been accomplished by using a multifaceted, multi-disciplinary approach that includes a range of activities, from characterizing the shallow subsurface to acquiring new explosion data both in the near field (< 100 m from the source) to the far field (> 100 m to 10 s km from the source). The Source Physics Experiment (SPE) is a collaborative project between National Security Technologies, LLC, Lawrence Livermore National Laboratory, Los Alamos National Laboratory, Sandia National Laboratories, the Defense Threat Reduction Agency, and the Air Force Technical Applications Center. The goal of the SPE is to understand the transition of seismic energy from the near field to the far field; to understand the development of S-waves in explosives sources; and to understand how anisotropy controls seismic energy transmission and partitioning. To fully explore these problems, the SPE test series includes tests in both simple and complex geology cases. The current series is being conducted in a highly fractured granite body. This location was chosen, in part, because it was the location of previous nuclear tests in the same rock body and because generally the geology has been well characterized. In addition to historic data, high-resolution seismic reflection, cross-hole tomography, core samples, LIDAR, hyperspectral, and fracture mapping data have been acquired to further characterize and detect changes after each of the shot across the test bed. The complex geology series includes 7 planned shots using conventional explosives in the same shot hole surrounded by Continuous Reflectometry for Radius vs. Time Experiment (CORRTEX), Time of Arrival, Velocity of Detonation, down-hole accelerometers, surface accelerometers

Extraction of toxic compounds from saliva by magnetic-stirring-assisted micro-solid-phase extraction step followed by headspace-gas chromatography-ion mobility spectrometry.

PubMed

Criado-García, Laura; Arce, Lourdes

2016-09-01

A new sample extraction procedure based on micro-solid-phase extraction (μSPE) using a mixture of sorbents of different polarities (polymeric reversed-phase sorbent HLB, silica-based sorbent C18, and multiwalled carbon nanotubes) was applied to extract benzene, toluene, butyraldehyde, benzaldehyde, and tolualdehyde present in saliva to avoid interference from moisture and matrix components and enhance sensitivity and selectivity of the ion mobility spectrometry (IMS) methodology proposed. The extraction of target analytes from saliva samples by using μSPE were followed by the desorption step carried out in the headspace vials placed in the autosampler of the IMS device. Then, 200 μL of headspace was injected into the GC column coupled to the IMS for its analysis. The method was fully validated in terms of sensitivity, precision, and recovery. The LODs and LOQs obtained, when analytes were dissolved in saliva samples to consider the matrix effect, were within the range of 0.38-0.49 and 1.26-1.66 μg mL(-1), respectively. The relative standard deviations were <3.5 % for retention time and drift time values, which indicate that the method proposed can be applied to determine toxic compounds in saliva samples. Graphical abstract Summary of steps followed in the experimental set up of this work.

[Liquid chromatography-tandem mass spectrometry method for determination of 10 macrolide antibiotics in pork samples using on-line solid phase extraction purification].

PubMed

Zhang, Xiaoguang; Liu, Dong; Liu, Hongran; Li, Qiang; Li, Lili; Wang, Lixia; Zhang, Yan

2017-10-08

A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method based on-line solid phase extraction (SPE) purification was established to determine 10 macrolide antibiotics in pork samples. The samples were extracted with acetonitrile, and the extracts were dried with rotary evaporator at 40℃, then the analytes were dissolved with 2 mL phosphate buffer. The solutions were purified and concentrated by on-line SPE with HLB cartridges. The analytes were eluted with methanol, and then transferred to XBridge BEH C18 column, separated with the mobile phases of 10 mmol/L ammonium acetate aqueous solution and acetonitrile. Finally, the target analytes were detected by tandem mass spectrometry. The results showed that good linearity was obtained in the range of 0.1-200 μg/L for the 10 macrolide antibiotics with correlation coefficients better than 0.990. The limits of detection were in range of 0.05-0.30 μg/kg and the limits of quantitation were in range of 0.10-1.00 μg/kg. The recoveries of the method were in range of 69.6%-115.2% at the spiked levels of 0.10-10.0 μg/kg for all analytes, with the relative standard deviations less than 10%. The developed method can be used for the determination of the 10 macrolide antibiotics in pork samples.

DE-FG02-08ER64658 (OASIS) - Final Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharman, Jonathan

Project OASIS (Operation of Advanced Structures, Interfaces and Sub-components for MEAs) was a 12 month project that ran from 1st September 2008 to 31st August 2009, and was managed by the Department of Energy Office of Science, Chicago Office, as Award No DE-FG02-08ER64658, with Johnson Matthey Fuel Cells Inc. as the sole contractor. The project was completed on schedule, with technical successes (details below) and payment of the full grant award made by DOE. The aim of the project was the development of membrane electrode assemblies (MEAs) for H2/air polymer electrolyte membrane (PEM) fuel cells that would give higher performancemore » under hot/dry and dry operating conditions, ideally with no loss of performance under wet conditions. Reducing or eliminating the need for humidifying the incoming gases will allow significant system cost and size reduction for many fuel cell applications including automotive, stationary and back-up power, and portable systems. Portable systems are also of particular interest in military markets. In previous work Johnson Matthey Fuel Cells had developed very stable, corrosion-resistant catalysts suitable for resisting degradation by carbon corrosion in particular. These materials were applied within the OASIS project as they are considered necessary for systems such as automotive where multiple start-stop events are experienced. These catalysts were contrasted with more conventional materials in the design of catalyst layers and novel microporous layers (MPLs) and gas diffusion layer (GDL) combinations were also explored. Early on in the work it was shown how much more aggressive high temperature operation is than dry operation. At the same humidity, tests at 110?C caused much more dehydration than tests at 80?C and the high temperature condition was much more revealing of improvements made to MEA design. Alloy catalysts were introduced and compared with Pt catalysts with a range of particle sizes. It was apparent that the

The UHPLC-DAD fingerprinting method for analysis of extracellular metabolites of fungi of the genus Geosmithia (Acomycota: Hypocreales).

PubMed

Tylová, Tereza; Kolařík, Miroslav; Olšovská, Jana

2011-07-01

A new simple ultra-high-performance liquid chromatography method with diode array detection (UHPLC-DAD) was developed for chemical fingerprinting analysis of extracellular metabolites in fermentation broth of Geosmithia spp. The SPE method employing Oasis MCX strong cation-exchange mixed-mode polymeric sorbent was chosen for extraction of the metabolites. The analyses were performed on an Acquity UPLC BEH C18 column (100 × 2.1 mm i.d.; particle size, 1.7 μm; Waters) using a gradient elution program with an aqueous solution of trifluoroacetic acid and acetonitrile as the mobile phase. The applicability of the method was proved by analysis of 38 strains produced by different species and isolated from different sources (hosts). The results revealed the correlation of obtained UHPLC-DAD fingerprints with taxonomical identity.

Optimization of extraction methods for quantification of microcystin-LR and microcystin-RR in fish, vegetable, and soil matrices using UPLC-MS/MS.

PubMed

Manubolu, Manjunath; Lee, Jiyoung; Riedl, Kenneth M; Kua, Zi Xun; Collart, Lindsay P; Ludsin, Stuart A

2018-06-01

Human-driven environmental change has increased the occurrence of harmful cyanobacteria blooms in aquatic ecosystems. Concomitantly, exposure to microcystin (MC), a cyanobacterial toxin that can accumulate in animals, edible plants, and agricultural soils, has become a growing public health concern. For accurate estimation of health risks and timely monitoring, availability of reliable detection methods is imperative. Nonetheless, quantitative analysis of MCs in many types of biological and environmental samples has proven challenging because matrix interferences can hinder sample preparation and extraction procedures, leading to poor MC recovery. Herein, controlled experiments were conducted to enhance the use of ultra-performance liquid-chromatography tandem-mass spectrometry (UPLC-MS/MS) to recover MC-LR and MC-RR at a range of concentrations in seafood (fish), vegetables (lettuce), and environmental (soil) matrices. Although these experiments offer insight into detailed technical aspects of the MC homogenization and extraction process (i.e., sonication duration and centrifugation speed during homogenization; elution solvent to use during the final extraction), they centered on identifying the best (1) solvent system to use during homogenization (2-3 tested per matrix) and (2) single-phase extraction (SPE) column type (3 tested) to use for the final extraction. The best procedure consisted of the following, regardless of sample type: centrifugation speed = 4200 × g; elution volume = 8 mL; elution solvent = 80% methanol; and SPE column type = hydrophilic-lipophilic balance (HLB), with carbon also being satisfactory for fish. For sonication, 2 min, 5 min, and 10 min were optimal for fish, lettuce, and soil matrices, respectively. Using the recommended HLB column, the solvent systems that led to the highest recovery of MCs were methanol:water:butanol for fish, methanol:water for lettuce, and EDTA-Na 4 P 2 O 7 for soils. Given that the

Development and validation of a solid-phase extraction method coupled with HPLC-UV detection for the determination of biogenic amines in Chinese rice wine.

PubMed

Zhang, Ying; Li, Yan; Zhu, Xiao-Juan; Li, Min; Chen, Hao-Yu; Lv, Xiao-Ling; Zhang, Jian

2017-07-01

A reliable and accurate method for the determination of seven biogenic amines (BAs) was developed and validated with Chinese rice wine samples. The BAs were derivatised with dansyl chloride, cleaned up using solid-phase extraction (SPE) and separated by high-performance liquid chromatography (HPLC) coupled with ultraviolet (UV) detection. The optimised derivatisation reaction, conducted at pH 9.6 and 60°C for 30 min, ensured baseline separation and peak symmetry for each BA. SPE clean-up using Oasis MCX cartridges yielded good recovery rates for all BAs and effectively reduced matrix effects. The developed method shows good linearity with determination coefficients of more than 0.9989 over a concentration range of 0.1-100 mg l -1 . The limits of detection (LODs) for the investigated BAs ranged from 2.07 to 5.56 µg l -1 . The intra- and inter-day relative standard deviations (RSDs) ranged from 0.86% to 3.81% and from 2.13% to 3.82%, respectively. Spiking experiments showed that the overall recovery rates ranged from 85% to 113%. Thus, the proposed method was demonstrated as being suitable for simultaneous detection, with accurate and precise quantification, of BAs in Chinese rice wine.

Evaluation of Irrigation Water Use Efficiency and Water-saving in the Middle Oasis of Heihe River Basin Using a Distributed Agro-hydrological Model

NASA Astrophysics Data System (ADS)

Jiang, Y.; Huang, G., Sr.; Xu, X.; Huang, Q.; Huo, Z.

2015-12-01

Severe water scarcity and unreasonable allocation are threatening the eco-environment in the Heihe River basin (HRB), an arid and semi-arid watershed in Northwest China. The water use in the middle oasis accounts for about 70% of the total water use in the HRB, in which over 85% are consumed by irrigated agriculture. Thus the regional assessment and improvement of irrigation water use are quite essential for water-saving and eco-environmental sustainability. This paper applied a distributed agro-hydrological model (SWAP-EPIC) integrated with ArcGIS to investigate the irrigation water use efficiency (WUE) in the middle oasis. The detailed distributed data in 2012, including soil properties, irrigation schedules, crop pattern and calendar, were collected and used in the regional simulation. The spatial-temporal distribution of LAI and evapotranspiration (ETa) from remote sensing were used as observations to calibrate the model. Results showed that the simulation data was in a good agreement with the observation one. The relative WUE (i.e. divided by the mean value) ranged from 0.77 to 1.33 in different canal command areas. Large spatial variations of WUE were mainly caused by the non-uniform distribution of irrigation water. The present irrigation performance was poor, and only 50% of total irrigation amount was finally utilized through evapotranspiration in the whole district. While nearly 24% of the irrigation water were lost through field deep percolation and 26% were wasted in canal conveyance. Further analysis of water-saving scenarios was conducted through applying the improved irrigation schedule for each crop-soil unites and increasing the canal conveyance efficiency. Prediction showed that 15% of total irrigation amount can be saved without reduction of crop yield.

An endangered oasis of aquatic microbial biodiversity in the Chihuahuan desert

PubMed Central

Souza, Valeria; Espinosa-Asuar, Laura; Escalante, Ana E.; Eguiarte, Luis E.; Farmer, Jack; Forney, Larry; Lloret, Lourdes; Rodríguez-Martínez, Juan M.; Soberón, Xavier; Dirzo, Rodolfo; Elser, James J.

2006-01-01

The Cuatro Cienegas basin in the Chihuahuan desert is a system of springs, streams, and pools. These ecosystems support >70 endemic species and abundant living stromatolites and other microbial communities, representing a desert oasis of high biodiversity. Here, we combine data from molecular microbiology and geology to document the microbial biodiversity of this unique environment. Ten water samples from locations within the Cuatro Cienegas basin and two neighboring valleys as well as three samples of wet sediments were analyzed. The phylogeny of prokaryotic populations in the samples was determined by characterizing cultured organisms and by PCR amplification and sequencing of 16S rRNA genes from total community DNA. The composition of microbial communities was also assessed by determining profiles of terminal restriction site polymorphisms of 16S rRNA genes in total community DNA. There were 250 different phylotypes among the 350 cultivated strains. Ninety-eight partial 16S rRNA gene sequences were obtained and classified. The clones represented 38 unique phylotypes from ten major lineages of Bacteria and one of Archaea. Unexpectedly, 50% of the phylotypes were most closely related to marine taxa, even though these environments have not been in contact with the ocean for tens of millions of years. Furthermore, terminal restriction site polymorphism profiles and geological data suggest that the aquatic ecosystems of Cuatro Cienegas are hydrologically interconnected with adjacent valleys recently targeted for agricultural intensification. The findings underscore the conservation value of desert aquatic ecosystems and the urgent need for study and preservation of freshwater microbial communities. PMID:16618921

Carbon balance of a plastic mulch and drip irrigated cotton field in an arid oasis of Northwest China

NASA Astrophysics Data System (ADS)

Ming, G.

2017-12-01

Carbon balance of a plastic mulch and drip irrigated cotton field in an arid oasis of Northwest ChinaGuanghui Ming1, Fuqiang Tian1*, Hongchang Hu11State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing, China,Abstracts: Agricultural ecosystems have the potential to offset rising CO2 concentration in the atmosphere but the potential is often altered by agricultural management. Plastic film mulching and drip irrigation (PMDI) have been widespread for saving water and improving crop yield worldwide. To comprehensively assess the carbon balance and to detect the controlling factors of the carbon flux in a PMDI cotton field, experiments combining eddy covariance (EC) system, chamber method and crop sampling were implemented in an arid oasis of Xinjiang from the year 2012 to 2016. The annual net ecosystem exchange (NEE) was -250.18 ± 80.41 g C m-2 in the five years, which indicated that the filed was a much stronger carbon sink. After removal of the harvest of cotton as seed oil (Ch) of 108.81±7.57 g C m-2, the field was still a moderate carbon sink with net biome productivity (NBP) of 141.37±73.7 g C m-2. Soil temperature can explain 82% of seasonal variation of nighttime NEE while PAR can explain 36-81% of daytime NEE varying with crop development and photosynthetic activity. NEE was separated into total ecosystem respiration (Reco, 1214.20±144.42 g C m-2) and gross primary productivity (GPP, 1464.38±122.78 g C m-2). Interannual Reco changed more drastically than GPP and respiration may be the main determinant of carbon balance in the PMDI field. Seasonal NPP measured by cop sampling method (NPPCS) agreed well with NPP calculated with EC (NPPEC), with the annual NPP of 708.86 ± 52.26 g C m-2, which indicated that our carbon flux measurements and separating methods reasonable. The PMDI cotton field induced more GPP and Reco than other croplands with larger light use efficiency (LUE) but relatively

[Effects of residue management and fertilizer application mode on soil organic carbon pools in an oasis cotton region.

PubMed

Zhang, Peng Peng; Liu, Yan Jie; Pu, Xiao Zhen; Zhang, Guo Juan; Wang, Jin; Zhang, Wang Feng

2016-11-18

To reveal the regulation mechanisms of agricultural management practices on soil organic carbon (SOC) pools and provide scientific basis for improving soil productivity and formulating agricultural fixed carbon and reducing discharge measures, we monitored the changes of SOC pools and organic carbon fractions in an oasis cotton field under different residue management and fertilizer application modes. A split-plot experimental design was used with differing residue management including residue incorporation (S) and residue removing (NS) in the main plots and differing fertilizer application modes including no fertilizer (CK), NPK fertilizer (NPK), organic manure (OM) and NPK fertilizer plus organic manure (NPK+OM) in the subplot. The results showed that fertilization and residue incorporation significantly increased SOC pool, soil organic carbon (C T ), labile carbon (C L ), microbial biomass carbon (C MB ), water-soluble organic carbon (C WS ), hot-water-soluble organic carbon (C HWS ), accumulative amount of soil organic carbon mineralization (C TM ) and carbon management index (CMI). The SOC pool was increased by 20.6% by residue incorporation compared to residue removing. SOC pools were increased by 7.8%, 29.5% and 37.7% in NPK, OM and NPK+OM treatments compared to CK, respectively. The contents of C T , C L , C MB , C WS and C HWS under different fertilization treatments were shown as NPK+OM>OM>NPK>CK. C TM was increased by 5.9% by residue incorporation compared to residue removing and C TM was increased by 32.7%, 59.5% and 97.3% in NPK, OM and NPK+OM treatments compared to CK, respectively. There was a significant correlation between CMI and C T , C MB , C L , C WS , C HWS , C TM , C pool and C sequestration. Therefore, we concluded that CMI is an important index for evaluating the effect of agricultural management practices on soil quality. In order to construct high-standard oasis farmland in arid region and develop cotton production, we should consider

Holocene environmental change at the oasis of Tayma

NASA Astrophysics Data System (ADS)

Engel, Max; Brückner, Helmut; Wellbrock, Kai; Pint, Anna; Grottker, Matthias; Voss, Peter; Ginau, Andreas; Klasen, Nicole; Frenzel, Peter

2013-04-01

The oasis of Tayma in northwestern Saudi Arabia has a rich cultural heritage comprising a large number of historic buildings and artefacts from the late Neolithic onwards. Extensive groundwater resources and the location at a branch of the Incense Road connecting south Arabia and the eastern Mediterranean determined the site's importance in Antiquity. This paper reports about Holocene environmental change at Tayma setting the frame for the interpretation of the archaeological record. Humid conditions during the early Holocene are inferred for the Arabian Peninsula (AP) based on the investigation of sabkhas, palaeo-lakes, sand dunes, wadis, speleothems and marine sediments. Most of these climate archives are located in the southern and southeastern part of the AP, where a northward shift of the Intertropical Convergence Zone (ITCZ) triggered increased rainfall at the onset of the Holocene. At Tayma, where the influence of the ITCZ shift can be excluded, the sedimentary infill of a sabkha basin, the micro- and macrofaunal record, a digital elevation model based on DGPS measurements, and 14C-AMS data indicate the presence of a perennial lake with a minimum depth of 13 m, a stored water volume of 1.16 107 m3 and a surface of 18.45 km2 between 10,000-9000 cal BP. Foraminiferal test malformations and the shape of sieve pores on ostracod valves were used to detect trends in palaeo-salinity and ecological stress conditions. Contraction of the lake at least after 8500 cal BP is a response to a long-term aridisation trend subsequent to the early Holocene. Based on the hydrological water balance equation, quantitative data on minimum palaeo-rainfall during the early Holocene humid period were determined. Input parameters for the equation are the minimum lake level, lake surface and lake volume during the peak of the early Holocene humid period as well as palaeo-evapotranspiration, groundwater infiltration, and surface runoff. A perennial lake in the endorheic basin of the

Recent Modifications and Validation of QuEChERS-dSPE Coupled to LC-MS and GC-MS Instruments for Determination of Pesticide/Agrochemical Residues in Fruits and Vegetables: Review.

PubMed

Lawal, Abubakar; Wong, Richard Chee Seng; Tan, Guan Huat; Abdulra'uf, Lukman Bola; Alsharif, Ali Mohamed Ali

2018-04-21

Fruits and vegetables constitute a major type of food consumed daily apart from whole grains. Unfortunately, the residual deposits of pesticides in these products are becoming a major health concern for human consumption. Consequently, the outcome of the long-term accumulation of pesticide residues has posed many health issues to both humans and animals in the environment. However, the residues have previously been determined using conventionally known techniques, which include liquid-liquid extraction, solid-phase extraction (SPE) and the recently used liquid-phase microextraction techniques. Despite the positive technological effects of these methods, their limitations include; time-consuming, operational difficulty, use of toxic organic solvents, low selective property and expensive extraction setups, with shorter lifespan of instrumental performances. Thus, the potential and maximum use of these methods for pesticides residue determination has resulted in the urgent need for better techniques that will overcome the highlighted drawbacks. Alternatively, attention has been drawn recently towards the use of quick, easy, cheap, effective, rugged and safe technique (QuEChERS) coupled with dispersive solid-phase extraction (dSPE) to overcome the setback challenges experienced by the previous technologies. Conclusively, the reviewed QuEChERS-dSPE techniques and the recent cleanup modifications justifiably prove to be reliable for routine determination and monitoring the concentration levels of pesticide residues using advanced instruments such as high-performance liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry.

On-line SPE-UHPLC method using fused core columns for extraction and separation of nine illegal dyes in chilli-containing spices.

PubMed

Khalikova, Maria A; Satínský, Dalibor; Smidrkalová, Tereza; Solich, Petr

2014-12-01

The presented work describes the development of a simple, fast and effective on-line SPE-UHPLC-UV/vis method using fused core particle columns for extraction, separation and quantitative analysis of the nine illegal dyes, most frequently found in chilli-containing spices. The red dyes Sudan I-IV, Sudan Red 7B, Sudan Red G, Sudan Orange G, Para Red, and Methyl Red were separated and analyzed in less than 9 min without labor-consuming pretreatment procedure. The chromatographic separation was performed on Ascentis Express RP-Amide column with gradient elution using mixture of acetonitrile and water, as a mobile phase at a flow rate of 1.0 mL min(-1) and 55°C of temperature. As SPE sorbent for cleanup and pre-concentration of illegal dyes short guard fused core column Ascentis Express F5 was used. The applicability of proposed method was proven for three different chilli-containing commercial samples. Recoveries for all compounds were between 90% and 108% and relative standard deviation ranged from 1% to 4% for within- and from 2% to 6% for between-day. Limits of detection showed lower values than required by European Union regulations and were in the range of 3.3-10.3 µg L(-1) for standard solutions, 5.6-235.6 µg kg(-1) for chilli-containing spices. Copyright © 2014 Elsevier B.V. All rights reserved.

[Simultaneous determination of 22 typical pharmaceuticals and personal care products in environmental water using ultra performance liquid chromatography- triple quadrupole mass spectrometry].

PubMed

Wu, Chunying; Gu, Feng; Bai, Lu; Lu, Wenlong

2015-08-01

An analytical method for simultaneous determination of 22 typical pharmaceuticals and personal care products (PPCPs) in environmental water samples was developed by ultra performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-MS/MS). An Oasis HLB solid phase extraction cartridge, methanol as washing solution, water containing 0. 1% formic acid-methanol (7:3, v/v) as the mobile phases were selected for sample pretreatment and chromatographic separation. Based on the optimized sample pretreatment procedures and separation condition, the target recoveries ranged from 73% to 125% in water with the relative standard deviations ( RSDs) from 8.8% to 17.5%, and the linear ranges were from 2 to 2 000 µg/L with correlation coefficients (R2) not less than 0.997. The method can be applied to simultaneous determination of the 22 typical PPCPs in environmental water samples because of its low detection limits and high recoveries. It can provide support and help for the related research on water environmental risk assessment and control of the micro-organic pollutants.

Hair testing for cocaine and metabolites by GC/MS: criteria to quantitatively assess cocaine use.

PubMed

López-Guarnido, O; Álvarez, I; Gil, F; Rodrigo, L; Cataño, H C; Bermejo, A M; Tabernero, M J; Pla, A; Hernández, A F

2013-08-01

A simple, rapid and sensitive method has been developed and validated for the determination of cocaine and its main metabolites (benzoylecgonine and cocaethylene) in human hair. The method involved solid-phase extraction with an Oasis HLB extraction cartridge and subsequent analysis by GC/MS. The limit of detection was 0.01 ng mg(-1) for cocaine, 0.04 for benzoylecgonine and 0.03 for cocaethylene. The method validation included linearity (with a correlation coefficient >0.99 over the range 0.2-50 ng mg(-1) ), intra- and inter-day precision (always lower than 12%) and accuracy (mean relative error always below 17%) to meet the bioanalytical acceptance criteria. The procedure was further applied to 40 hair samples from self-reported cocaine users arrested by the police who provided a positive urine-analysis for cocaine, and was demonstrated to be suitable for its application in forensic toxicology. New approaches were raised to detect false-negative results that allow a better interpretation of hair testing results. Copyright © 2012 John Wiley & Sons, Ltd.

Determination of sulfonamides in selected Malaysian swine wastewater by high-performance liquid chromatography.

PubMed

Malintan, Nancy T; Mohd, Mustafa Ali

2006-09-15

An analytical HPLC method for the simultaneous determination of eight sulfonamides in swine wastewater was developed. The samples were collected from three states in Malaysia. Sample clean up was carried out by employing solid-phase extraction using a 60 mg Oasis HLB (Waters) cartridge with 3 ml reservoir. The HPLC column used was Supelcosil C18 (250 mm x 4.6mm I.D.) and elution was carried out using gradient mode. The mobile phases used were acetonitrile and 0.5% acetic acid in purified water. Antibiotics were detected using UV absorbance at 272 nm. Recoveries obtained for sulphanilamide ranged from 31.9+/-5.1% to 36.2+/-1.0%, while recoveries for other sulfa drugs studied were from 91.9+/-5.0% to 106.0+/-1.1%. The limit of quantitation (LOQ) for sulfamerazine, sulfamethazine and sulfamethoxypyridazine was 7.5 ng/L, while the LOQ for the other studied antibiotics was 5.0 ng/L. The method was used to analyse sulfonamides in wastewater collected from selected Malaysian swine facilities.

Development and validation of an LC-UV method for the determination of sulfonamides in animal feeds.

PubMed

Kumar, P; Companyó, R

2012-05-01

A simple LC-UV method was developed for the determination of residues of eight sulfonamides (sulfachloropyridazine, sulfadiazine, sulfadimidine, sulfadoxine, sulfamethoxypyridazine, sulfaquinoxaline, sulfamethoxazole, and sulfadimethoxine) in six types of animal feed. C18, Oasis HLB, Plexa and Plexa PCX stationary phases were assessed for the clean-up step and the latter was chosen as it showed greater efficiency in the clean-up of interferences. Feed samples spiked with sulfonamides at 2 mg/kg were used to assess the trueness (recovery %) and precision of the method. Mean recovery values ranged from 47% to 66%, intra-day precision (RSD %) from 4% to 15% and inter-day precision (RSD %) from 7% to 18% in pig feed. Recoveries and intra-day precisions were also evaluated in rabbit, hen, cow, chicken and piglet feed matrices. Calibration curves with standards prepared in mobile phase and matrix-matched calibration curves were compared and the matrix effects were ascertained. The limits of detection and quantification in the feeds ranged from 74 to 265 µg/kg and from 265 to 868 µg/kg, respectively. Copyright © 2011 John Wiley & Sons, Ltd.

Impact of artificial recharge and drought in Tafilalet Oasis system: First investigation by GIS and groundwater modeling

NASA Astrophysics Data System (ADS)

Bouaamlat, I.; Larabi, A.; Faouzi, M.

2013-12-01

The geographical location of Tafilalet oasis system (TOS) in the south of the valley of Ziz (Morocco) offers him a particular advantage on the plane of water potential. The surface water which comes from humid regions of the High Atlas and intercepted by a dam then converged through the watercourse of Ziz towards the plain of the TOS, have created the conditions for the formation of a water table relatively rich with regard to the local climatic conditions (arid climate with recurrent drought). Because of this situation, the region has one of the largest palms of North Africa. Thus there is an agricultural activity that is practiced in a 21 irrigation areas whose size rarely exceeds 2,000 hectare. Given the role of the water table in the economic development of the region, a hydrogeological study was conducted to understand the impact of artificial recharge and recurrent droughts on the development of the groundwater reserves of TOS. In this study, a three-dimensional model of groundwater flow was developed for the Tafilalet oasis system aquifer, to assist the decision makers as a "management tool" in order to assess alternative schemes for development and exploitation of groundwater resources based on the variation of artificial recharge and drought, using for the first time the Modflow code. This study takes into account the most possible real hydrogeological conditions and using the geographical information system (GIS) for the organisation and treatment of data and applying a multidisciplinary approach combining geostatistical and hydrogeological modeling. The results from this numerical investigation of the TOS aquifer shows that the commissioning of the dam to control the flows of extreme flood and good management of water releases, has avoided the losses of irrigation water and consequently the non-overexploitation of the groundwater. So that with one or two water releases per year from the dam of flow rate more than 14 million m3/year it is possible to

Internal evaporation and condensation characteristics in the shallow soil layer of an oasis

NASA Astrophysics Data System (ADS)

Ao, Yinhuan; Han, Bo; Lu, Shihua; Li, Zhaoguo

2016-07-01

The surface energy balance was analyzed using observations from the Jinta oasis experiment in the summer of 2005. A negative imbalance energy flux was found during daytime that could not be attributed to the soil heat storage process. Rather, the imbalance was related to the evaporation within the soil. The soil heat storage rate and the soil moisture variability always showed similar variations at a depth of 0.05 m between 0800 and 1000 (local standard time), while the observed imbalanced energy flux was very small, which implied that water vapor condensation occurred within the soil. Therefore, the distillation in shallow soil can be derived using reliable surface energy flux observations. In order to show that the importance of internal evaporation and condensation in the shallow soil layer, the soil temperatures at the depths of 0.05, 0.10, and 0.20 m were reproduced using a one-dimensional thermal diffusion equation, with the observed soil temperature at the surface and at 0.40 m as the boundary conditions. It was found that the simulated soil temperature improves substantially in the shallow layer when the water distillation is added as a sink/source term, even after the soil effective thermal conductivity has been optimized. This result demonstrates that the process of water distillation may be a dominant cause of both the temperature and moisture variability in the shallow soil layer.

An exploration of adult body shape and limb proportions at Kellis 2, Dakhleh Oasis, Egypt.

PubMed

Bleuze, Michele M; Wheeler, Sandra M; Dupras, Tosha L; Williams, Lana J; El Molto, J

2014-03-01

Several studies have shown that the human body generally conforms to the ecogeographical expectations of Bergmann's and Allen's rules; however, recent evidence suggests that these expectations may not hold completely for some populations. Egypt is located at the crossroads of Sub-Saharan Africa, Southern Europe, and the Near East, and gene flow among groups in these regions may confound ecogeographical patterning. In this study, we test the fit of the adult physique of a large sample (N = 163) of females and males from the Kellis 2 cemetery (Dakhleh Oasis, Egypt) against ecogeographical predictions. Body shape (i.e., body mass relative to stature) was assessed by the femur head diameter to bicondylar femur length index (FHD/BFL), and brachial and crural indices were calculated to examine intralimb proportions. Body shape in the Kellis 2 sample is not significantly different from high-latitude groups and a Lower Nubian sample, and intralimb proportions are not significantly different from mid-latitude and other low-latitude groups. This study demonstrates the potential uniqueness of body shape and intralimb proportions in an ancient Egyptian sample, and further highlights the complex relationship between ecogeographic patterning and adaptation. Copyright © 2013 Wiley Periodicals, Inc.

[Speciation Characteristics and Bioavailability of Heavy Metals in Oasis Soil Under Pb, Zn Combined Stress].

PubMed

Jin, Cheng; Zhao, Zhuan-jun; Nan, Zhong-ren; Wang, Sheng-li; Wu, Wen-fei; Wang, Hou-cheng

2015-05-01

Pot experiments were conducted on cole (Brassica) grown in oasis soil under combined stress of lead and zinc, to study the effect of heavy metal combined pollution on cole growth as well as the speciation conversion rules and bioavailability. The result showed that the promoting effect on cole growth was shown in the low concentration treatments, especially on stem leaves. With addition of exotic heavy metals, the main speciations of Pb and Zn in the soil transformed from tight-bound to loose-bound forms as compared to the control, and the bioavailability of heavy metals was increased. And, the exchangeable Pb and the carbonate bound form of Zn were the major contributing speciations which were absorbed in different parts of cole. What's more, the capabilities of uptake and translocation of Pb and Zn by cole were stronger at lower stress levels, and the enrichment and migration coefficients decreased with the increasing content of bioavailable fraction of the corresponding element or the coexisting element. In all treatments, the Pb concentration in the stem leaves of cole exceeded the food safety threshold, therefore it is recommended to conduct detection of relevant indicators before planting foliage vegetables in this kind of soil.

Timing of large earthquakes since A.D. 800 on the Mission Creek strand of the San Andreas fault zone at Thousand Palms Oasis, near Palm Springs, California

USGS Publications Warehouse

Fumal, T.E.; Rymer, M.J.; Seitz, G.G.

2002-01-01

Paleoseismic investigations across the Mission Creek strand of the San Andreas fault at Thousand Palms Oasis indicate that four and probably five surface-rupturing earthquakes occurred during the past 1200 years. Calendar age estimates for these earthquakes are based on a chronological model that incorporates radio-carbon dates from 18 in situ burn layers and stratigraphic ordering constraints. These five earthquakes occurred in about A.D. 825 (770-890) (mean, 95% range), A.D. 982 (840-1150), A.D. 1231 (1170-1290), A.D. 1502 (1450-1555), and after a date in the range of A.D. 1520-1680. The most recent surface-rupturing earthquake at Thousand Palms is likely the same as the A.D. 1676 ?? 35 event at Indio reported by Sieh and Williams (1990). Each of the past five earthquakes recorded on the San Andreas fault in the Coachella Valley strongly overlaps in time with an event at the Wrightwood paleoseismic site, about 120 km northwest of Thousand Palms Oasis. Correlation of events between these two sites suggests that at least the southernmost 200 km of the San Andreas fault zone may have ruptured in each earthquake. The average repeat time for surface-rupturing earthquakes on the San Andreas fault in the Coachella Valley is 215 ?? 25 years, whereas the elapsed time since the most recent event is 326 ?? 35 years. This suggests the southernmost San Andreas fault zone likely is very near failure. The Thousand Palms Oasis site is underlain by a series of six channels cut and filled since about A.D. 800 that cross the fault at high angles. A channel margin about 900 years old is offset right laterally 2.0 ?? 0.5 m, indicating a slip rate of 4 ?? 2 mm/yr. This slip rate is low relative to geodetic and other geologic slip rate estimates (26 ?? 2 mm/yr and about 23-35 mm/yr, respectively) on the southernmost San Andreas fault zone, possibly because (1) the site is located in a small step-over in the fault trace and so the rate is not be representative of the Mission Creek fault

The economic potential of El-Gedida glauconite deposits, El-Bahariya Oasis, Western Desert, Egypt

NASA Astrophysics Data System (ADS)

El-Habaak, Galal; Askalany, Mohamed; Faraghaly, Mohamed; Abdel-Hakeem, Mahmoud

2016-08-01

The mining work at El-Gedida iron mine, El-Bahariya Oasis, in the Western Desert of Egypt extracts commercial iron ore deposits without attention paid to the large glauconite deposits overlying these iron ore deposits. For this reason, the present paper aims at evaluating and attracting the attention to these glauconite deposits as alternative potassium fertilizers. The study was achieved by investigating mineralogical, physical and chemical properties of the green deposits. Mineralogical and physical properties involved the determination of glauconite pellets content in different grain size fractions relative to impurities and the analysis of the percentage of clay matrix and grain size distribution. Different pre-treatment strategies and methods including comminution, sieving, magnetic separation, and X-ray diffraction were used for investigating those mineralogical and physical properties. On the other hand, chemical analyses included potassium content, heavy metal concentrations, and pH and salinity measurements. The major elements and trace elements were measured using ICP-OES and the pH was measured using a pH conductometer. Moreover, this study investigated the nature of grain boundaries and the effect of sieving on glauconite beneficiation. Results of this study suggest that El-Gedida glauconite deposits are mineralogically, physically and chemically suitable for exploitation and can be beneficiated for use as an alternative potassium fertilizer.

Regional spatial-temporal spread of citrus huanglongbing is affected by rain in Florida.

PubMed

Shimwela, Mpoki; Schubert, Timothy S; Albritton, Matthew; Halbert, Susan E; Jones, Debra J; Sun, Xiaoan; Roberts, Pamela; Singer, Burton; Lee, Wen Suk; Jones, Jeffrey B; Ploetz, Randy; van Bruggen, Ariena H C

2018-06-06

Citrus huanglongbing (HLB), associated with Candidatus Liberibacter asiaticus (Las), disseminated by Asian Citrus Psyllid (ACP), has devastated citrus in Florida since 2005. Data on HLB occurrence were stored in databases (2005-2012). Cumulative HLB-positive citrus blocks were subjected to kernel density analysis and kriging. Relative disease incidence per county was calculated by dividing HLB numbers by relative tree numbers and maximum incidence. Spatio-temporal HLB distributions were correlated with weather. Relative HLB incidence correlated positively with rainfall. The focus expansion rate was 1626 m month-1, similar to that in Brazil. Relative HLB incidence in counties with primarily large groves increased at a lower rate (0.24 year-1) than in counties with smaller groves in hotspot areas (0.67 year-1), confirming reports that large-scale HLB management may slow epidemic progress.

Edible seaweed as future functional food: Identification of α-glucosidase inhibitors by combined use of high-resolution α-glucosidase inhibition profiling and HPLC-HRMS-SPE-NMR.

PubMed

Liu, Bingrui; Kongstad, Kenneth T; Wiese, Stefanie; Jäger, Anna K; Staerk, Dan

2016-07-15

Crude chloroform, ethanol and acetone extracts of nineteen seaweed species were screened for their antioxidant and α-glucosidase inhibitory activity. Samples showing more than 60% α-glucosidase inhibitory activity, at a concentration of 1 mg/ml, were furthermore investigated using high-resolution α-glucosidase inhibition profiling combined with high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy (HR-bioassay/HPLC-HRMS-SPE-NMR). The results showed Ascophyllum nodosum and Fucus vesicolosus to be rich in antioxidants, equaling a Trolox equivalent antioxidant capacity of 135 and 108 mM Troloxmg(-1) extract, respectively. HR-bioassay/HPLC-HRMS-SPE-NMR showed the α-glucosidase inhibitory activity of A. nodosum, F. vesoculosus, Laminaria digitata, Laminaria japonica and Undaria pinnatifida to be caused by phlorotannins as well as fatty acids - with oleic acid, linoleic acid and eicosapentaenoic acid being the most potent with IC50 values of 0.069, 0.075 and 0.10 mM, respectively, and showing a mixed-type inhibition mode. Copyright © 2016 Elsevier Ltd. All rights reserved.

Production of unusual dispiro metabolites in Pestalotiopsis virgatula endophyte cultures: HPLC-SPE-NMR, electronic circular dichroism, and time-dependent density-functional computation study.

PubMed

Kesting, Julie R; Olsen, Lars; Staerk, Dan; Tejesvi, Mysore V; Kini, Kukkundoor R; Prakash, Harishchandra S; Jaroszewski, Jerzy W

2011-10-28

The endophytic fungus Pestalotiopsis virgatula, derived from the plant Terminalia chebula and previously found to produce a large excess of a single metabolite when grown in the minimal M1D medium, was induced to produce a variety of unusual metabolites by growing in potato dextrose broth medium. Analysis of the fermentation medium extract was performed using an HPLC-PDA-MS-SPE-NMR hyphenated system, which led to the identification of a total of eight metabolites (1-8), six of which are new. Most of the metabolites are structurally related and are derivatives of benzo[c]oxepin, rare among natural products. This includes dispiro derivatives 7 and 8 (pestalospiranes A and B), having a novel 1,9,11,18-tetraoxadispiro[6.2.6.2]octadecane skeleton. Relative and absolute configurations of the latter were determined by a combination of NOESY spectroscopy and electronic circular dichroism spectroscopy supported by time-dependent density-functional theory calculations (B3LYP/TZVP level). This work demonstrates that a largely complete structure elucidation of numerous metabolites present in a raw fermentation medium extract can be performed by the HPLC-SPE-NMR technique using only a small amount of the extract, even with unstable metabolites that are difficult to isolate by traditional methods.

Uranus' post-equinox north polar brightening characterized with 2013 and 2016 IRTF SpeX observation

NASA Astrophysics Data System (ADS)

Fry, Patrick M.; Sromovsky, Lawrence A.

2017-10-01

Since its 2007 equinox, the atmosphere of Uranus, as seen in the near infrared (~800-1600 nm) has exhibited dramatic changes. Its southern polar cap, prominent prior to equinox, has faded and a similar polar cap has begun developing in the north. Karkoschka and Tomasko (2009, Icarus 202:287) demonstrated that in 2002 the south polar region, brighter than lower latitude regions when viewed at wavelengths of intermediate methane absorption, was depleted in methane compared to darker regions. Tice et al. (2013, Icarus 223:684) and Sromovsky et al. (2014, Icarus 238:137) concluded that the northern polar regions were similarly depleted. The north polar region (45N-90N) has continued to brighten; modeling of 2015 HST STIS observations (Fry et al. 2016, AAS DPS #48 421.03) suggested that the latitudinal methane distribution has remained essentially unchanged since equinox, but brightening from 2012 to 2015 was due to changes in aerosol scattering. We acquired 0.8-2.5 μm SpeX spectra in 2013 (central meridian) and 2016 (pole-aligned spectra at 0, 0.4, 0.8, and 1.2 arcsec. distant from the CM) under similar seeing conditions (0.4-0.5 arcsec.). The SpeX wavelength range gives us an additional wavelength region where H2 absorption competes with or exceeds CH4 absorption, and a wider wavelength range to characterize aerosol particle properties, compared to STIS. The multiple spectra in 2016 allow us to compare specific latitudes to 2013 at the same view angles (and to use center-to-limb constraints in modeling 2016 spectra). We will present observations, reduction procedures, comparative (2013 vs 2016) modeling of latitudinal methane abundance and vertical aerosol profiles, and compare to 2012/2015 STIS analysis. Preliminary analysis shows that lower latitudes (~30N) have not changed since 2013, but higher latitudes (~70N) have undergone continued significant brightening at pseudo-continuum wavelengths dominated by both H2 (1080 nm, up ~50%) and CH4 (1290 nm, also up ~50

Radiation dose predictions for SPE events during solar cycle 23 from NASA's Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model

NASA Astrophysics Data System (ADS)

Mertens, Christopher; Blattnig, Steve; Slaba, Tony; Kress, Brian; Wiltberger, Michael; Solomon, Stan

NASA's High Charge and Energy Transport (HZETRN) code is a deterministic model for rapid and accurate calculations of the particle radiation fields in the space environment. HZETRN is used to calculate dosimetric quantities on the International Space Station (ISS) and assess astronaut risk to space radiations, including realistic spacecraft and human geometry for final exposure evaluation. HZETRN is used as an engineering design tool for materials research for radiation shielding protection. Moreover, it is used to calculate HZE propagation through the Earth and Martian atmospheres, and to evaluate radiation exposures for epidemiological studies. A new research project has begun that will use HZETRN as the transport engine for the development of a nowcast prediction of air-crew radiation exposure for both background galactic cosmic ray (GCR) exposure and radiation exposure during solar particle events (SPE) that may accompany solar storms. The new air-crew radiation exposure model is called the Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model, which utilizes real-time observations from ground-based, atmospheric, and satellite measurements. In this paper, we compute the global distribution of atmospheric radiation dose for several SPE events during solar cycle 23, with particular emphasis on the high-latitude and polar region. We also characterize the suppression of the geomagnetic cutoff rigidity during these storm periods and their subsequent influence on atmospheric radiation exposure.

Development and Application of a Novel SPE-Method for Bioassay-Guided Fractionation of Marine Extracts

PubMed Central

Cutignano, Adele; Nuzzo, Genoveffa; Ianora, Adrianna; Luongo, Elvira; Romano, Giovanna; Gallo, Carmela; Sansone, Clementina; Aprea, Susanna; Mancini, Francesca; D’Oro, Ugo; Fontana, Angelo

2015-01-01

The biological diversity of marine habitats is a unique source of chemical compounds with potential use as pharmaceuticals, cosmetics and dietary supplements. However, biological screening and chemical analysis of marine extracts pose specific technical constraints and require adequate sample preparation. Here we report an improved method on Solid Phase Extraction (SPE) to fractionate organic extracts containing high concentration of salt that hampers the recovery of secondary metabolites. The procedure uses a water suspension to load the extracts on a poly(styrene-divynylbenzene)-based support and a stepwise organic solvent elution to effectively desalt and fractionate the organic components. The novel protocol has been tested on MeOH-soluble material from three model organisms (Reniera sarai, Dendrilla membranosa and Amphidinium carterae) and was validated on a small panel of 47 marine samples, including sponges and protists, within discovery programs for identification of immuno-stimulatory and anti-infective natural products. PMID:26378547

Seismic source functions from free-field ground motions recorded on SPE: Implications for source models of small, shallow explosions

NASA Astrophysics Data System (ADS)

Rougier, Esteban; Patton, Howard J.

2015-05-01

Reduced displacement potentials (RDPs) for chemical explosions of the Source Physics Experiments (SPE) in granite at the Nevada Nuclear Security Site are estimated from free-field ground motion recordings. Far-field P wave source functions are proportional to the time derivative of RDPs. Frequency domain comparisons between measured source functions and model predictions show that high-frequency amplitudes roll off as ω- 2, but models fail to predict the observed seismic moment, corner frequency, and spectral overshoot. All three features are fit satisfactorily for the SPE-2 test after cavity radius Rc is reduced by 12%, elastic radius is reduced by 58%, and peak-to-static pressure ratio on the elastic radius is increased by 100%, all with respect to the Mueller-Murphy model modified with the Denny-Johnson Rc scaling law. A large discrepancy is found between the cavity volume inferred from RDPs and the volume estimated from laser scans of the emplacement hole. The measurements imply a scaled Rc of ~5 m/kt1/3, more than a factor of 2 smaller than nuclear explosions. Less than 25% of the seismic moment can be attributed to cavity formation. A breakdown of the incompressibility assumption due to shear dilatancy of the source medium around the cavity is the likely explanation. New formulas are developed for volume changes due to medium bulking (or compaction). A 0.04% decrease of average density inside the elastic radius accounts for the missing volumetric moment. Assuming incompressibility, established Rc scaling laws predicted the moment reasonable well, but it was only fortuitous because dilation of the source medium compensated for the small cavity volume.

Novel radiosynthesis of PET HSV-tk gene reporter probes [18F]FHPG and [18F]FHBG employing dual Sep-Pak SPE techniques.

PubMed

Wang, Ji-Quan; Zheng, Qi-Huang; Fei, Xiangshu; Mock, Bruce H; Hutchins, Gary D

2003-11-17

Positron emission tomography (PET) herpes simplex virus thymidine kinase (HSV-tk) gene reporter probes 9-[(3-[(18)F]fluoro-1-hydroxy-2-propoxy)methyl]guanine ([(18)F]FHPG) and 9-(4-[(18)F]fluoro-3-hydroxymethylbutyl)guanine ([(18)F]FHBG) were prepared by nucleophilic substitution of the appropriate tosylated precursors with [(18)F]KF/Kryptofix 2.2.2 followed by a quick deprotection reaction and purification with a simplified dual Silica Sep-Pak solid-phase extraction (SPE) method in 15-30% radiochemical yield.

Simultaneous and confirmative detection of multi-residues of β₂-agonists and β-blockers in urine using LC-MS/MS/MS coupled with β-receptor molecular imprinted polymer SPE clean-up.

PubMed

Fan, S; Zou, J H; Miao, H; Zhao, Y F; Chen, H J; Zhao, R; Wu, Y N

2013-01-01

A liquid chromatography-linear ion-trap spectrometry (LC-MS³) method using β-receptor molecular-imprinted polymer (MIP) solid-phase extraction (SPE) as clean-up was developed to determine simultaneously and confirmatively residues of 25 β₂-agonists and 21 β-blockers in urine samples. Urine samples were subjected to enzymatic hydrolysis by β-glucoronidase/arylsulphatase, and then extracted with perchloric acid. Sample clean-up was performed using β-receptor MIP SPE. A Supelco Ascentis® express Rp-Amide column was used to separate the analytes, and MS³ detection used an electrospray ionisation source in positive-ion mode. Recovery studies were carried out using blank urine samples fortified with the 46 analytes at the levels of 0.5, 1.0 and 2.0 μg l⁻¹. Recoveries were obtained ranging from 60.1% to 109.9% with relative standard deviations (RSDs, n = 7) from 0.5% to 19.4%. The limits of detection (LODs) and limits of quantitation (LOQs) of the 46 analytes in urine were 0.02-0.18 and 0.05-0.60 μg l⁻¹, respectively. As a result of the selective clean-up by MIP SPE and MS³ detection of the target drugs, the sensitivity and accuracy of the present method was high enough for monitoring β₂-agonist and β-blocker residues in urine samples. Satisfactory results were obtained in the process of the determination of positive urine samples.

Polar low ionospheric responses to the most energetic SPE of the solar cycle#23 based on cosmic noise absorption

NASA Astrophysics Data System (ADS)

Pacini, A. A.; Garnett Marques Brum, C.

2013-12-01

We present a detailed study of the impact of solar proton event over the polar low ionosphere, occurred Jan/2005, during the descendent phase of the last solar activity cycle XXIII. This event was the hardest SPE of the last solar cycle, and was associated to a solar X-ray flare X.2 and CME halo. For this study, we are using cosmic noise absorption data measured by a riometer located in Oulu, Finland (65N) along with solar proton data from GOES satellite. Based on computation simulations we intend to explain the 30MHz riometer absorption events based on variations of the flux and spectrum of the energetic particle precipitated.

Multidetection of antibiotics in liver tissue by ultra-high-pressure-liquid-chromatography-tandem mass spectrometry.

PubMed

Freitas, Andreia; Barbosa, Jorge; Ramos, Fernando

2015-01-22

A multiresidue quantitative screening method covering 39 antibiotics from 7 different families by ultra-high-pressure-liquid-chromatography-tandem mass spectrometry (UHPLC-MS/MS) is described. Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol are simultaneously detected in liver tissue. A simple sample treatment method consisting of extraction with a mixture of acetonitrile and ethylenediaminetetraacetic acid (EDTA) followed by solid-phase extraction (SPE) with a hydrophilic-lipophilic balanced (HLB) cartridge was developed. The methodology was validated, in accordance with Decision 2002/657/EC, by evaluating the following required parameters: decision limit (CCα), detection capability (CCβ), specificity, repeatability and reproducibility. The precision, in terms of the relative standard deviation, was under 22% for all of the compounds, and the recoveries were between 80% and 110%. The CCα and CCβ were determined according to the maximum residue limit (MRL) or the minimum required performance limit (MRPL), when established. Copyright © 2014 Elsevier B.V. All rights reserved.

SPE-LEEM Studies on the Surface and Electronic Structure of 2-D Transition Metal Dichalcogenides

NASA Astrophysics Data System (ADS)

Yeh, Po-Chun; Jin, Wencan; Zaki, Nader; Zhang, Datong; Sadowski, Jerzy; Al-Mahboob, Abdullah; van de Zande, Arend; Chenet, Daniel; Dadap, Jerry; Herman, Irving; Sutter, Petter; Hone, James; Osgood, Richard

2014-03-01

In this work, we studied the surface and electronic structure of monolayer and few-layer exfoliated MoS2 and WSe2, as well as chemical-vapor-deposition (CVD) grown MoS2, using Spectroscopic Photoemission and Low Energy Electron Microscope (SPE-LEEM). LEEM measurements reveal that, unlike exfoliated MoS2, CVD-grown MoS2 exhibits grain-boundary alterations due to surface strain. However, LEEM and micro-probe low energy electron diffraction show that the quality of CVD-grown MoS2 is comparable to that of exfoliated MoS2. Micrometer-scale angle-resolved photoemission spectroscopy (ARPES) measurement on exfoliated MoS2 and WSe2 single-crystals provides direct evidence for the shifting of the valence band maximum from Γ to K, when the layer number is thinned down to one, as predicted by density functional theory. Our measurements of the k-space resolved electronic structure allow for further comparison with other theoretical predictions and with transport measurements. Session I and II

Determination of acrylamide in coffee and coffee products by GC-MS using an improved SPE clean-up.

PubMed

Soares, C; Cunha, S; Fernandes, J

2006-12-01

An improved gas chromatography-mass spectrometry (GC-MS) method to determine acrylamide (AA) in coffee and coffee products was developed. The method was based on two main purification steps: the first with ethanol and Carrez solutions in order to precipitate polysaccharides and proteins, respectively; and the second with a layered solid-phase extraction (SPE) column which proved to be efficient in the elimination of the main chromatographic interferences. The method is applicable to a wide range of coffee products. Twenty-six samples of different coffee products were analysed. The levels of AA were in the range 11.4-36.2 microg l-1 for 'espresso coffee' and 200.8-229.4 microg l-1 for coffee blends with cereals. The results indicate that the presence of cereals significantly increased the levels of AA.

Therapeutic drug monitoring of topiramate with a new HPLC method, SPE extraction and high sensitivity pre-column fluorescent derivatization.

PubMed

Bolner, Andreas; De Riva, Valentina; Galloni, Elisabetta; Perini, Francesco

2014-01-01

Topiramate is a 2nd generation antiepileptic drug (AED) recently approved by the FDA for migraine prophylaxis. Its pharmacological activity already appears significant at low doses. Unfortunately, the difficulty in determining the drug in serum at low concentrations hampers the completion of accurate pharmacokinetic studies in humans. Only chromatographic methods allow reaching the necessary sensitivities. Almost all of the HPLC methods proposed were based on the preliminary extraction of topiramate from the sample using organic solvents. In our study, the conditions for purifying topiramate through solid-liquid technique in disposable cartridges (SPE) packed with C18 reversed phase were examinated and optimised. After a pre-column derivatization step with 9-fluorenylmethyl chloroformate (FMOC-Cl) and internal standard addition, topiramate was analysed on a CN column with sodium phosphate buffer 50 mmol/L (pH 2.5) containing acetonitrile (60:40, v/v) as the mobile phase. The column effluent was monitored with a fluorescence detector (excitation and emission 1 260 and 315 nm, respectively). 122 samples from our routine laboratory work were analysed in order to confirm the existence of a relationship between topiramate dose and serum concentration and to evaluate the effect of concomitant therapies with enzyme-inducing AEDs. Sensitivity (2 ng/mL), precision (CV within assay of 3.8% and between assays of 6.6%), linearity and accuracy of the method were better than other analytical procedures previously reported. Serum topiramate levels in the group with enzyme-inducing AEDs showed a reduction with respect to the group with non-enzyme-inducing AEDs and the correlation between doses and mean serum concentration gives a linear trend (r2 = 0.916). The efficacy of SPE extraction together with the method's reliability proved very advantageous for pharmacokinetics studies and, in principle, for therapeutic drug monitoring and toxicological investigations.

Source spectra of the first four Source Physics Experiments (SPE) explosions from the frequency-domain moment-tensor inversion

DOE PAGES

Yang, Xiaoning

2016-08-01

In this study, I used seismic waveforms recorded within 2 km from the epicenter of the first four Source Physics Experiments (SPE) explosions to invert for the moment-tensor spectra of these explosions. I employed a one-dimensional (1D) Earth model for Green's function calculations. The model was developed from P- and R g-wave travel times and amplitudes. I selected data for the inversion based on the criterion that they had consistent travel times and amplitude behavior as those predicted by the 1D model. Due to limited azimuthal coverage of the sources and the mostly vertical-component-only nature of the dataset, only long-period,more » volumetric components of the moment-tensor spectra were well constrained.« less

Emergence of the Epidemic Methicillin-Resistant Staphylococcus aureus Strain USA300 Coincides with Horizontal Transfer of the Arginine Catabolic Mobile Element and speG-mediated Adaptations for Survival on Skin

PubMed Central

Planet, Paul J.; LaRussa, Samuel J.; Dana, Ali; Smith, Hannah; Xu, Amy; Ryan, Chanelle; Uhlemann, Anne-Catrin; Boundy, Sam; Goldberg, Julia; Narechania, Apurva; Kulkarni, Ritwij; Ratner, Adam J.; Geoghegan, Joan A.; Kolokotronis, Sergios-Orestis; Prince, Alice

2013-01-01

ABSTRACT The arginine catabolic mobile element (ACME) is the largest genomic region distinguishing epidemic USA300 strains of methicillin-resistant Staphylococcus aureus (MRSA) from other S. aureus strains. However, the functional relevance of ACME to infection and disease has remained unclear. Using phylogenetic analysis, we have shown that the modular segments of ACME were assembled into a single genetic locus in Staphylococcus epidermidis and then horizontally transferred to the common ancestor of USA300 strains in an extremely recent event. Acquisition of one ACME gene, speG, allowed USA300 strains to withstand levels of polyamines (e.g., spermidine) produced in skin that are toxic to other closely related S. aureus strains. speG-mediated polyamine tolerance also enhanced biofilm formation, adherence to fibrinogen/fibronectin, and resistance to antibiotic and keratinocyte-mediated killing. We suggest that these properties gave USA300 a major selective advantage during skin infection and colonization, contributing to the extraordinary evolutionary success of this clone. PMID:24345744

Stratospheric hydrogen peroxide (H2O2): Comparison between MIPAS observations and KASIMA model results with focus on the SPE 2003

NASA Astrophysics Data System (ADS)

Versick, S.

2009-04-01

H, OH and HO2 (collectively called HOx) are fast-reacting radicals in the middle atmosphere. These radicals are efficient catalysts for destroying ozone and play an important role in atmospheric chemistry. An important reservoir gas for HOx is Hydrogen Peroxide (H2O2). For all these important species at the moment only few measurements exist, e.g. in-situ measurements in the troposphere, balloon and rocket measurements, few HOx measurements by aircraft, and global satellite measurements of OH and HO2 by Aura/MLS since 2005. We present results for H2O2 for global day and night measurements with the MIPAS instrument on the ESA satellite ENVISAT. We find is a strong annual cycle with high values for H2O2 in polar summer consitent with the strong coupling to HOx chemistry. We investigated in more detail the Solar Proton Event (SPE) that occurred in October/November 2003. During SPEs, precipitation of energetic protons into the polar atmosphere produces ions in the middle atmosphere which form, partly via ion-cluster-reactions, odd hydrogen (HOx ) and odd nitrogen (NOx ). Increased levels of HOx and NOx, in turn, depletes the ozone in the polar stratosphere and mesosphere. We present the results of our retrievals of H2O2 for this event and compare the observations with results of the KASIMA model which has been upgraded to handle the ionization of the atmosphere due to the SPE and subsequent chemical reactions due to the NOx/HOx enhancements.

Polar low ionospheric responses to the most energetic SPE of the solar cycle#23 based on cosmic noise absorption

NASA Astrophysics Data System (ADS)

Pacini, A. A.; Brum, C. G.

2013-05-01

We present a detailed study of the impact of solar proton event over the polar low ionosphere, occurred in Jan/2005, during the descendent phase of the XXIII solar activity cycle. This event was the hardest SPE of the last solar cycle, and was associated to a solar X-ray flare X.2 and CME halo. For this study, we are using cosmic noise absorption data measured by a riometer located in Oulu, Finland (65oN) along with solar proton data from GOES satellite. Based on computation simulations we intend to explain the 30MHz riometer absorption events based on variations of the flux and spectrum of the energetic particle precipitated.

Analysis of nitrosamines in water by automated SPE and isotope dilution GC/HRMS Occurrence in the different steps of a drinking water treatment plant, and in chlorinated samples from a reservoir and a sewage treatment plant effluent.

PubMed

Planas, Carles; Palacios, Oscar; Ventura, Francesc; Rivera, Josep; Caixach, Josep

2008-08-15

A method based on automated solid-phase extraction (SPE) and isotope dilution gas chromatography/high resolution mass spectrometry (GC/HRMS) has been developed for the analysis of nine nitrosamines in water samples. The combination of automated SPE and GC/HRMS for the analysis of nitrosamines has not been reported previously. The method shows as advantages the selectivity and sensitivity of GC/HRMS analysis and the high efficiency of automated SPE with coconut charcoal EPA 521 cartridges. Low method detection limits (MDLs) were achieved, along with a greater facility of the procedure and less dependence on the operator with regard to the methods based on manual SPE. Quality requirements for isotope dilution-based methods were accomplished for most analysed nitrosamines, regarding to trueness (80-120%), method precision (<15%) and MDLs (0.08-1.7 ng/L). Nineteen water samples (16 samples from a drinking water treatment plant {DWTP}, 2 chlorinated samples from a sewage treatment plant {STP} effluent, and 1 chlorinated sample from a reservoir) were analysed. Concentrations of nitrosamines in the STP effluent were 309.4 and 730.2 ng/L, being higher when higher doses of chlorine were applied. N-Nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) were the main compounds identified in the STP effluent, and NDEA was detected above 200 ng/L, regulatory level for NDMA in effluents stated in Ontario (Canada). Lower concentrations of nitrosamines were found in the reservoir (20.3 ng/L) and in the DWTP samples (n.d. -28.6 ng/L). NDMA and NDEA were respectively found in the reservoir and in treated and highly chlorinated DWTP samples at concentrations above 10 ng/L (guide value established in different countries). The highest concentrations of nitrosamines were found after chlorination and ozonation processes (ozonated, treated and highly chlorinated water) in DWTP samples.

Geologic map of the Oasis Valley basin and vicinity, Nye County, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fridrich, C.J.; Minor, S.A.; Ryder, P.L.

2000-01-13

This map and accompanying cross sections present an updated synthesis of the geologic framework of the Oasis Valley area, a major groundwater discharge site located about 15 km west of the Nevada Test Site. Most of the data presented in this compilation is new geologic map data, as discussed below. In addition, the cross sections incorporate new geophysical data that have become available in the last three years (Grauch and others, 1997; written comm., 1999; Hildenbrand and others, 1999; Mankinen and others, 1999). Geophysical data are used to estimate the thickness of the Tertiary volcanic and sedimentary rocks on themore » cross sections, and to identify major concealed structures. Large contiguous parts of the map area are covered either by alluvium or by volcanic units deposited after development of the major structures present at the depth of the water table and below. Hence, geophysical data provide critical constraints on our geologic interpretations. A companion paper by Fridrich and others (1999) and the above-cited reports by Hildenbrand and others (1999) and Mankinen and others (1999) provide explanations of the interpretations that are presented graphically on this map. This map covers nine 7.5-minute quadrangles in Nye County, Nevada, centered on the Thirsty Canyon SW quadrangle, and is a compilation of one published quadrangle map (O'Connor and others, 1966) and eight new quadrangle maps, two of which have been previously released (Minor and others, 1997; 1998). The cross sections that accompany this map were drawn to a depth of about 5 km below land surface at the request of hydrologists who are modeling the Death Valley groundwater system.« less

Arctic springtime observations of volatile organic compounds during the OASIS-2009 campaign

NASA Astrophysics Data System (ADS)

Hornbrook, Rebecca S.; Hills, Alan J.; Riemer, Daniel D.; Abdelhamid, Aroob; Flocke, Frank M.; Hall, Samuel R.; Huey, L. Gregory; Knapp, David J.; Liao, Jin; Mauldin, Roy L.; Montzka, Denise D.; Orlando, John J.; Shepson, Paul B.; Sive, Barkley; Staebler, Ralf M.; Tanner, David. J.; Thompson, Chelsea R.; Turnipseed, Andrew; Ullmann, Kirk; Weinheimer, Andrew J.; Apel, Eric C.

2016-08-01

Gas-phase volatile organic compounds (VOCs) were measured at three vertical levels between 0.6 m and 5.4 m in the Arctic boundary layer in Barrow, Alaska, for the Ocean-Atmosphere-Sea Ice-Snowpack (OASIS)-2009 field campaign during March-April 2009. C4-C8 nonmethane hydrocarbons (NMHCs) and oxygenated VOCs (OVOCs), including alcohols, aldehydes, and ketones, were quantified multiple times per hour, day and night, during the campaign using in situ fast gas chromatography-mass spectrometry. Three canister samples were also collected daily and subsequently analyzed for C2-C5 NMHCs. The NMHCs and aldehydes demonstrated an overall decrease in mixing ratios during the experiment, whereas acetone and 2-butanone showed increases. Calculations of time-integrated concentrations of Br atoms, ∫[Br]dt, yielded values as high as (1.34 ± 0.27) × 1014 cm-3 s during the longest observed ozone depletion event (ODE) of the campaign and were correlated with the steady state Br calculated at the site during this time. Both chlorine and bromine chemistry contributed to the large perturbations on the production and losses of VOCs. Notably, acetaldehyde, propanal, and butanal mixing ratios dropped below the detection limit of the instrument (3 parts per trillion by volume (pptv) for acetaldehyde and propanal, 2 pptv for butanal) during several ODEs due to Br chemistry. Chemical flux calculations of OVOC production and loss are consistent with localized high Cl-atom concentrations either regionally or within a very shallow surface layer, while the deeper Arctic boundary layer provides a continuous source of precursor alkanes to maintain the OVOC mixing ratios.

Transcriptome comparison and gene coexpression network analysis provide a systems view of citrus response to ‘Candidatus Liberibacter asiaticus’ infection

PubMed Central

2013-01-01

Background Huanglongbing (HLB) is arguably the most destructive disease for the citrus industry. HLB is caused by infection of the bacterium, Candidatus Liberibacter spp. Several citrus GeneChip studies have revealed thousands of genes that are up- or down-regulated by infection with Ca. Liberibacter asiaticus. However, whether and how these host genes act to protect against HLB remains poorly understood. Results As a first step towards a mechanistic view of citrus in response to the HLB bacterial infection, we performed a comparative transcriptome analysis and found that a total of 21 Probesets are commonly up-regulated by the HLB bacterial infection. In addition, a number of genes are likely regulated specifically at early, late or very late stages of the infection. Furthermore, using Pearson correlation coefficient-based gene coexpression analysis, we constructed a citrus HLB response network consisting of 3,507 Probesets and 56,287 interactions. Genes involved in carbohydrate and nitrogen metabolic processes, transport, defense, signaling and hormone response were overrepresented in the HLB response network and the subnetworks for these processes were constructed. Analysis of the defense and hormone response subnetworks indicates that hormone response is interconnected with defense response. In addition, mapping the commonly up-regulated HLB responsive genes into the HLB response network resulted in a core subnetwork where transport plays a key role in the citrus response to the HLB bacterial infection. Moreover, analysis of a phloem protein subnetwork indicates a role for this protein and zinc transporters or zinc-binding proteins in the citrus HLB defense response. Conclusion Through integrating transcriptome comparison and gene coexpression network analysis, we have provided for the first time a systems view of citrus in response to the Ca. Liberibacter spp. infection causing HLB. PMID:23324561

A feasible methodology for groundwater resource modelling for sustainable use in sparse-data drylands: Application to the Amtoudi Oasis in the northern Sahara.

PubMed

Alcalá, Francisco J; Martín-Martín, Manuel; Guerrera, Francesco; Martínez-Valderrama, Jaime; Robles-Marín, Pedro

2018-07-15

In a previous paper, the Amtoudi Oasis, a remote area in the northern Sahara in southern Morocco, was chosen to model the dynamics of groundwater-dependent economics under different scenarios of water availability, both the wet 2009-2010 and the average 2010-2011 hydrological years. Groundwater imbalance was reflected by net aquifer recharge (R) less than groundwater allotment for agriculture and urban uses in the average year 2010-2011. Three key groundwater sustainability issues from the hydrologic perspective were raised for future research, which are addressed in this paper. Introducing a feasible methodology for groundwater resource modelling for sustainable use in sparse-data drylands, this paper updates available databases, compiles new databases, and introduces new formulations to: (1) refine the net groundwater balance (W) modelling for years 2009-2010 and 2010-2011, providing the magnitude of net lateral inflow from adjacent formations (R L ), the largest R component contributing to the oasis; (2) evaluate the non-evaporative fraction of precipitation (P) (B) from 1973 onward as a proxy of the potential renewable water resource available for use; and (3) define the critical balance period for variables to reach a comparable stationary condition, as prerequisite for long-term modelling of W. R L was about 0.07-fold P and 0.85-fold R. Historical yearly B-to-P ratios were 0.02 for dry, 0.04 for average, and 0.07 for wet hydrological years; the average yearly P being 124mm. A critical 17-year balance period with stable relative error below 0.1 was defined from the 44-year P and B time-series statistical study. This is the monitoring period proposed for the stationary evaluation of the variables involved in the long-term modelling of W. This paper seeks to offer a feasible methodology for groundwater modelling addressed for planning sustainable water policies in sparse-data drylands. Copyright © 2018 Elsevier B.V. All rights reserved.

Sequence stratigraphy of the Lower Cenomanian Bahariya Formation, Bahariya Oasis, Western Desert, Egypt

NASA Astrophysics Data System (ADS)

Catuneanu, O.; Khalifa, M. A.; Wanas, H. A.

2006-08-01

The Lower Cenomanian Bahariya Formation corresponds to a second-order depositional sequence that formed within a continental shelf setting under relatively low-rate conditions of positive accommodation (< 200 m during 3-6 My). This overall trend of base-level rise was interrupted by three episodes of base-level fall that resulted in the formation of third-order sequence boundaries. These boundaries are represented by subaerial unconformities (replaced or not by younger transgressive wave ravinement surfaces), and subdivide the Bahariya Formation into four third-order depositional sequences. The construction of the sequence stratigraphic framework of the Bahariya Formation is based on the lateral and vertical changes between shelf, subtidal, coastal and fluvial facies, as well as on the nature of contacts that separate them. The internal (third-order) sequence boundaries are associated with incised valleys, which explain (1) significant lateral changes in the thickness of incised valley fill deposits, (2) the absence of third-order highstand and even transgressive systems tracts in particular areas, and (3) the abrupt facies shifts that may occur laterally over relatively short distances. Within each sequence, the concepts of lowstand, transgressive and highstand systems tracts are used to explain the observed lateral and vertical facies variability. This case study demonstrates the usefulness of sequence stratigraphic analysis in understanding the architecture and stacking patterns of the preserved rock record, and helps to identify 13 stages in the history of base-level changes that marked the evolution of the Bahariya Oasis region during the Early Cenomanian.

Characterisation of antimicrobial extracts from dandelion root (Taraxacum officinale) using LC-SPE-NMR.

PubMed

Kenny, O; Brunton, N P; Walsh, D; Hewage, C M; McLoughlin, P; Smyth, T J

2015-04-01

Plant extracts have traditionally been used as sources of natural antimicrobial compounds, although in many cases, the compounds responsible for their antimicrobial efficacy have not been identified. In this study, crude and dialysed extracts from dandelion root (Taraxacum officinale) were evaluated for their antimicrobial properties against Gram positive and Gram negative bacterial strains. The methanol hydrophobic crude extract (DRE3) demonstrated the strongest inhibition of microbial growth against Staphylococcus aureus, methicillin-resistant S. aureus and Bacillus cereus strains. Normal phase (NP) fractionation of DRE3 resulted in two fractions (NPF4 and NPF5) with enhanced antimicrobial activity. Further NP fractionation of NPF4 resulted in two fractions (NPF403 and NPF406) with increased antimicrobial activity. Further isolation and characterisation of compounds in NPF406 using liquid chromatography solid phase extraction nuclear magnetic resonance LC-SPE-NMR resulted in the identification of 9-hydroxyoctadecatrienoic acid and 9-hydroxyoctadecadienoic acid, while the phenolic compounds vanillin, coniferaldehyde and p-methoxyphenylglyoxylic acid were also identified respectively. The molecular mass of these compounds was confirmed by LC mass spectroscopy (MS)/MS. In summary, the antimicrobial efficacy of dandelion root extracts demonstrated in this study support the use of dandelion root as a source of natural antimicrobial compounds. Copyright © 2015 John Wiley & Sons, Ltd.

Tale of the Huanglongbing Disease Pyramid in the Context of the Citrus Microbiome.

PubMed

Wang, Nian; Stelinski, Lukasz L; Pelz-Stelinski, Kirsten S; Graham, James H; Zhang, Yunzeng

2017-04-01

The Huanglongbing (HLB) disease pyramid is composed of Liberibacters, psyllid vectors, citrus hosts, and the environment. The epidemiological outcomes for Liberibacter-associated plant diseases are collectively determined by the inherent relationships among plant-Liberibacters-psyllids, and how various environmental factors affect plant-Liberibacter-psyllid interactions. Citrus-Liberibacter-psyllid interactions occur in a complex microbiome system. In this review, we focus on the progress in understanding the HLB disease pyramid, and how the microbiome affects the HLB disease pyramid including the interaction between HLB and the citrus microbiome; the interaction between Liberibacters and psyllids; the interaction between Liberibacters and gut microbiota in psyllids; and the effect of HLB on selected above- and belowground citrus pathogens. Their implications for HLB management are also discussed.

Assessment of groundwater and soil quality degradation using multivariate and geostatistical analyses, Dakhla Oasis, Egypt

NASA Astrophysics Data System (ADS)

Masoud, Alaa A.; El-Horiny, Mohamed M.; Atwia, Mohamed G.; Gemail, Khaled S.; Koike, Katsuaki

2018-06-01

Salinization of groundwater and soil resources has long been a serious environmental hazard in arid regions. This study was conducted to investigate and document the factors controlling such salinization and their inter-relationships in the Dakhla Oasis (Egypt). To accomplish this, 60 groundwater samples and 31 soil samples were collected in February 2014. Factor analysis (FA) and hierarchical cluster analysis (HCA) were integrated with geostatistical analyses to characterize the chemical properties of groundwater and soil and their spatial patterns, identify the factors controlling the pattern variability, and clarify the salinization mechanism. Groundwater quality standards revealed emergence of salinization (av. 885.8 mg/L) and extreme occurrences of Fe2+ (av. 17.22 mg/L) and Mn2+ (av. 2.38 mg/L). Soils were highly salt-affected (av. 15.2 dS m-1) and slightly alkaline (av. pH = 7.7). Evaporation and ion-exchange processes governed the evolution of two main water types: Na-Cl (52%) and Ca-Mg-Cl (47%), respectively. Salinization leads the chemical variability of both resources. Distinctive patterns of slight salinization marked the northern part and intense salinization marked the middle and southern parts. Congruence in the resources clusters confirmed common geology, soil types, and urban and agricultural practices. Minimizing the environmental and socioeconomic impacts of the resources salinization urges the need for better understanding of the hydrochemical characteristics and prediction of quality changes.

HPLC confirmatory method development for the determination of seven quinolones in salmon tissue (Salmo salar L.) validated according to the European Union Decision 2002/657/EC.

PubMed

Evaggelopoulou, Evaggelia N; Samanidou, Victoria F

2013-01-15

A confirmatory high pressure liquid chromatographic method for the determination of seven quinolone antibiotics in tissue of Atlantic salmon (Salmo salar L.) was developed. Ciprofloxacin (CIP), danofloxacin (DAN), enrofloxacin (ENR), sarafloxacin (SAR), oxolinic acid (OXO), nalidixic acid (NAL) and flumequine (FLU) were separated on a Perfectsil ODS-2 120 (250 mm × 4 mm, 5 μm) column by gradient elution with a mobile phase consisting of 0.1% trifluoroacetic acid (pH=1), acetonitrile and methanol at 25°C within 22 min. Analytes were monitored at 255 nm (for the determination of OXO, NAL and FLU) and 275 nm (for CIP, DAN, ENR and SAR) by means of photodiode array detector. Examined quinolones were isolated from salmon tissue by extraction with citrate buffer solution (pH=4.7) and purified by solid phase extraction using Oasis HLB (200mg/6 mL) cartridges. The developed method was fully validated in terms of selectivity, linearity, accuracy, precision, stability and sensitivity according to the European Union Decision 2002/657/EC. The accuracy of the method was additionally proved by its application to certified reference material of salmon tissue (BCR® 725). Copyright © 2012 Elsevier Ltd. All rights reserved.

Multiresidue analysis of sulfonamides, quinolones, and tetracyclines in animal tissues by ultra-high performance liquid chromatography-tandem mass spectrometry.

PubMed

Zhang, Zhiwen; Li, Xiaowei; Ding, Shuangyang; Jiang, Haiyang; Shen, Jianzhong; Xia, Xi

2016-08-01

A multiresidue method for the efficient identification and quantification of 38 compounds from 3 different classes of antibiotics (tetracyclines, sulfonamides, and quinolones) in animal tissues has been developed. The method optimization involved the selection of extraction solutions, comparison of different solid-phase extraction cartridges and different mobile phases. As a result, the samples were extracted with Mcllvaine and phosphate buffers, followed by clean-up step based on solid-phase extraction with Oasis HLB cartridge. All compounds were determined by ultra-high performance liquid chromatography-tandem mass spectrometry, in one single injection with a chromatographic run time of only 9min. The method efficiency was evaluated in 5 tissues including muscle, liver, and kidney, and the mean recoveries ranged from 54% to 102%, with inter-day relative standard deviation lower than 14%. The limits of quantification were between 0.5 and 10μg/kg, which were satisfactory to support future surveillance monitoring. The developed method was applied to the analysis of swine liver and chicken samples from local markets, and sulfamethazine was the most commonly detected compound in the animal samples, with the highest residue level of 998μg/kg. Copyright © 2016 Elsevier Ltd. All rights reserved.

Validated univariate and multivariate spectrophotometric methods for the determination of pharmaceuticals mixture in complex wastewater

NASA Astrophysics Data System (ADS)

Riad, Safaa M.; Salem, Hesham; Elbalkiny, Heba T.; Khattab, Fatma I.

2015-04-01

Five, accurate, precise, and sensitive univariate and multivariate spectrophotometric methods were developed for the simultaneous determination of a ternary mixture containing Trimethoprim (TMP), Sulphamethoxazole (SMZ) and Oxytetracycline (OTC) in waste water samples collected from different cites either production wastewater or livestock wastewater after their solid phase extraction using OASIS HLB cartridges. In univariate methods OTC was determined at its λmax 355.7 nm (0D), while (TMP) and (SMZ) were determined by three different univariate methods. Method (A) is based on successive spectrophotometric resolution technique (SSRT). The technique starts with the ratio subtraction method followed by ratio difference method for determination of TMP and SMZ. Method (B) is successive derivative ratio technique (SDR). Method (C) is mean centering of the ratio spectra (MCR). The developed multivariate methods are principle component regression (PCR) and partial least squares (PLS). The specificity of the developed methods is investigated by analyzing laboratory prepared mixtures containing different ratios of the three drugs. The obtained results are statistically compared with those obtained by the official methods, showing no significant difference with respect to accuracy and precision at p = 0.05.

Validated univariate and multivariate spectrophotometric methods for the determination of pharmaceuticals mixture in complex wastewater.

PubMed

Riad, Safaa M; Salem, Hesham; Elbalkiny, Heba T; Khattab, Fatma I

2015-04-05

Five, accurate, precise, and sensitive univariate and multivariate spectrophotometric methods were developed for the simultaneous determination of a ternary mixture containing Trimethoprim (TMP), Sulphamethoxazole (SMZ) and Oxytetracycline (OTC) in waste water samples collected from different cites either production wastewater or livestock wastewater after their solid phase extraction using OASIS HLB cartridges. In univariate methods OTC was determined at its λmax 355.7 nm (0D), while (TMP) and (SMZ) were determined by three different univariate methods. Method (A) is based on successive spectrophotometric resolution technique (SSRT). The technique starts with the ratio subtraction method followed by ratio difference method for determination of TMP and SMZ. Method (B) is successive derivative ratio technique (SDR). Method (C) is mean centering of the ratio spectra (MCR). The developed multivariate methods are principle component regression (PCR) and partial least squares (PLS). The specificity of the developed methods is investigated by analyzing laboratory prepared mixtures containing different ratios of the three drugs. The obtained results are statistically compared with those obtained by the official methods, showing no significant difference with respect to accuracy and precision at p=0.05. Copyright © 2015 Elsevier B.V. All rights reserved.

Pressurized liquid extraction combined with capillary electrophoresis-mass spectrometry as an improved methodology for the determination of sulfonamide residues in meat.

PubMed

Font, Guillermina; Juan-García, Ana; Picó, Yolanda

2007-08-03

A new analytical method, based on capillary electrophoresis and tandem mass spectrometry (CE-MS2), is proposed and validated for the identification and simultaneous quantification of 12 sulfonamides (SAs) in pork meat. The studied SAs include sulfathiazole, sulfadiazine, sulfamethoxypyridazine, sulfaguanidine, sulfanilamide, sulfadimethoxyne, sulfapyridine, sulfachloropyridazine, sulfisoxazole, sulfasalazine, sulfabenzamide and sulfadimidine. Different parameters (i.e. separation buffer, sheath liquid, electrospray conditions) were optimized to obtain an adequate CE separation and high MS sensitivity. MS2 experiments using an ion trap as analyzer, operating in the selected reaction monitoring (SRM) mode, were carried out to achieve the required number of identification points according to the 2002/657/EC European Decision. For the quantification in pork tissue samples, a pressurized liquid extraction (PLE) procedure, using hot water as extractant followed by an Oasis HLB cleanup, was developed. Linearity (r between 0.996 and 0.997), precision (RSD<14 %) and recoveries (from 76 to 98%) were satisfactory. The limits of detection and quantification (below 12.5 and 46.5 microg kg(-1), respectively) were in all cases lower than the maximum residue limits (MRLs), indicating the potential of CE-MS2 for the analysis of SAs, in the food quality and safety control areas.

Stimulating high impact HIV-related cardiovascular research: recommendations from a multidisciplinary NHLBI Working Group on HIV-related heart, lung, and blood disease.

PubMed

Shah, Monica R; Cook, Nakela; Wong, Renee; Hsue, Priscilla; Ridker, Paul; Currier, Judith; Shurin, Susan

2015-02-24

The clinical challenges confronting patients with human immunodeficiency virus (HIV) have shifted from acquired immunodeficiency syndrome (AIDS)-related illnesses to chronic diseases, such as coronary artery disease, chronic lung disease, and chronic anemia. With the growing burden of HIV-related heart, lung, and blood (HLB) disease, the National Heart, Lung, and Blood Institute (NHLBI) recognizes it must stimulate and support HIV-related HLB research. Because HIV offers a natural, accelerated model of common pathological processes, such as inflammation, HIV-related HLB research may yield important breakthroughs for all patients with HLB disease. This paper summarizes the cardiovascular recommendations of an NHLBI Working Group, Advancing HIV/AIDS Research in Heart, Lung, and Blood Diseases, charged with identifying scientific priorities in HIV-related HLB disease and developing recommendations to promote multidisciplinary collaboration among HIV and HLB investigators. The working group included multidisciplinary sessions, as well as HLB breakout sessions for discussion of disease-specific issues, with common themes about scientific priorities and strategies to stimulate HLB research emerging in all 3 groups. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Microextraction of non-steroidal anti-inflammatory drugs from waste water samples by rotating-disk sorptive extraction.

PubMed

Manzo, Valentina; Honda, Luis; Navarro, Orielle; Ascar, Loreto; Richter, Pablo

2014-10-01

In this study, six non-steroidal anti-inflammatory drugs (NSAIDs) were extracted from water samples using the rotating-disk sorptive extraction (RDSE) technique. The extraction disk device contains a central cavity that allows for the incorporation of a powdered sorbent phase (Oasis™ HLB). The analytes were extracted from water and pre-concentrated on the sorbent to reach the extraction equilibrium, and then they were desorbed with solvent, derivatized and determined by gas chromatography-mass spectrometry (GC-MS). The variables for the extraction were studied using high performance liquid chromatography with a diode array detector (HPLC-DAD) to avoid the derivatization step, and the optimum values were as follows: 60 mg of Oasis™ HLB, a rotation velocity of 3,000 rpm, a pH of 2, a sample volume of 50 mL, and an extraction time of approximately 90-100 min. The recoveries ranged from 71 to 104%, with relative standard deviations (RSD) between 2 and 8%. The detection limits ranged from 0.001 to 0.033 µg L(-1). The described method was applied to the analysis of influents and effluents from wastewater treatment plants (WWTP) in Santiago, Chile. The concentrations of the detected drugs ranged from 1.5 to 13.4 µg L(-1) and from 1.0 to 3.2 µg L(-1) in the influents and effluents, respectively. The samples were extracted by solid phase extraction (SPE). No significant differences were observed in the determined concentrations for most of the NSAIDs, indicating that RDSE is an alternative method for the preparation of water samples. Copyright © 2014 Elsevier B.V. All rights reserved.

A sensitive microextraction by packed sorbent-based methodology combined with ultra-high pressure liquid chromatography as a powerful technique for analysis of biologically active flavonols in wines.

PubMed

Silva, Catarina L; Gonçalves, João L; Câmara, José S

2012-08-20

A new approach based on microextraction by packed sorbent (MEPS) and reversed-phase high-throughput ultra high pressure liquid chromatography (UHPLC) method that uses a gradient elution and diode array detection to quantitate three biologically active flavonols in wines, myricetin, quercetin, and kaempferol, is described. In addition to performing routine experiments to establish the validity of the assay to internationally accepted criteria (selectivity, linearity, sensitivity, precision, accuracy), experiments are included to assess the effect of the important experimental parameters such as the type of sorbent material (C2, C8, C18, SIL, and C8/SCX), number of extraction cycles (extract-discard), elution volume, sample volume, and ethanol content, on the MEPS performance. The optimal conditions of MEPS extraction were obtained using C8 sorbent and small sample volumes (250μL) in five extraction cycle and in a short time period (about 5min for the entire sample preparation step). Under optimized conditions, excellent linearity (R(values)(2)>0.9963), limits of detection of 0.006μgmL(-1) (quercetin) to 0.013μgmL(-1) (myricetin) and precision within 0.5-3.1% were observed for the target flavonols. The average recoveries of myricetin, quercetin and kaempferol for real samples were 83.0-97.7% with relative standard deviation (RSD, %) lower than 1.6%. The results obtained showed that the most abundant flavonol in the analyzed samples was myricetin (5.8±3.7μgmL(-1)). Quercetin (0.97±0.41μgmL(-1)) and kaempferol (0.66±0.24μgmL(-1)) were found in a lower concentration. The optimized MEPS(C8) method was compared with a reverse-phase solid-phase extraction (SPE) procedure using as sorbent a macroporous copolymer made from a balanced ratio of two monomers, the lipophilic divinylbenzene and the hydrophilic N-vinylpyrrolidone (Oasis HLB) were used as reference. MEPS(C8) approach offers an attractive alternative for analysis of flavonols in wines, providing a number of

Water quality in coastal wetlands: illicit drugs in surface waters of L'Albufera Natural Park (Valencia, Spain)

NASA Astrophysics Data System (ADS)

Vazquez-Roig, P.; Blasco, C.; Andreu, V.; Pascual, J. A.; Rubio, J. L.; Picó, Y.

2010-05-01

A wide range of emerging pollutants have been identified in environment: antibiotics, hormones, personal care products, etc. But quite recently a new class of ecological threat has been reported: the presence in waters of abuse drugs coming from human consumption [1,2]. Treatment of wastewaters may remove a portion of these compounds, but sometimes, these treatments are insufficient or nonexistent, residues can reach into the aquatic environment. ĹAlbufera Natural Park (Valencia, Spain) is a marsh area of a great interest because it is the habitat of a large quantity of unique species of flora and fauna, and a zone of refuge, feeding and breeding for a large number of migratory birds. However, this area is threatened by urban, industrial and agricultural pressures. The aim of this work has been to develop a fast and sensitive multi-residue analytical method for to establish the occurrence and distribution of commonly consumed illicit drugs in surface waters of ĹAlbufera lake. A representative set of abuse drugs with different mode of action was chosen for this purpose, including: amphetaminics, opiates, cocainics and cannabinoids (THC and nor-9-carboxy-THC). In April 2008 and October 2008 a total of 16 samples of water were collected, corresponding to different sampling points previously designed, and covering the most important channels that flow in to the lake. Samples of 250 mL of water were concentrated by Solid Phase Extraction through an Oasis HLB cartridge and extracted subsequently with methanol as solvent. Quantification was carried out by LC-MS/MS with an ESI interface. Performance characteristics of the PLE-SPE followed by LC-MS/MS were established by validation procedure. Selectivity, linearity, precision, recoveries and limits of detection (LOD) and quantification (LOQ) were studied. Our search shows that current sewage treatment systems do not completely remove illicit drug residues from urban wastewater. Benzoylecgonine, the main metabolite from

Identification of phenanthrene derivatives in Aerides rosea (Orchidaceae) using the combined systems HPLC-ESI-HRMS/MS and HPLC-DAD-MS-SPE-UV-NMR.

PubMed

Cakova, Veronika; Urbain, Aurélie; Antheaume, Cyril; Rimlinger, Nicole; Wehrung, Patrick; Bonté, Frédéric; Lobstein, Annelise

2015-01-01

In our continued efforts to contribute to the general knowledge on the chemical diversity of orchids, we have decided to focus our investigations on the Aeridinae subtribe. Following our previous phytochemical study of Vanda coerulea, which has led to the identification of phenanthrene derivatives, a closely related species, Aerides rosea Lodd. ex Lindl. & Paxton, was chosen for investigation. To identify new secondary metabolites, and to avoid isolation of those already known, by means of the combined systems HPLC-DAD(diode-array detector) with high-resolution tandem mass spectrometry (HRMS/MS) and HPLC-DAD-MS-SPE(solid-phase extraction)-UV-NMR. A dereplication strategy was developed using a HPLC-DAD-HRMS/MS targeted method and applied to fractions from A. rosea stem extract. Characterisation of unknown minor compounds was then performed using the combined HPLC-DAD-MS-SPE-UV-NMR system. The dereplication method allowed the characterisation of four compounds (gigantol, imbricatin, methoxycoelonin and coelonin), previously isolated from Vanda coerulea stem extract. The analyses of two fractions permitted the identification of five additional minor constituents including one phenanthropyran, two phenanthrene and two dihydrophenanthrene derivatives. The full set of NMR data of each compound was obtained from microgram quantities. Nine secondary metabolites were characterised in A. rosea stems, utilising HPLC systems combined with high-resolution analytical systems. Two of them are newly described phenanthrene derivatives: aerosanthrene (5-methoxyphenanthrene-2,3,7-triol) and aerosin (3-methoxy-9,10-dihydro-2,5,7-phenanthrenetriol). Copyright © 2014 John Wiley & Sons, Ltd.

Phase behavior of the mixtures of poly(oxyethylene) (10) stearyl ether (Brij-76), 1-butanol, isooctane, and mixed polar solvents II. Water and ethylene glycol (EG) or tetraethylene glycol (TEG).

PubMed

Nandy, Debdurlav; Mitra, Rajib K; Paul, Bidyut K

2007-06-01

The phase diagrams of the pseudo-quaternary systems poly(oxyethylene) (10) stearyl ether (Brij-76)/1-butanol/isooctane/water (with equal amounts of oil and water in the presence of two nonaqueous polar solvents (NPS), ethylene glycol (EG), and tetraethylene glycol (TEG)), have been constructed at 30 degrees C. Regular fish-tail diagrams were obtained up to psi (weight fraction of EG or TEG in the mixture of polar solvents) equal to 0.5, confirming the establishment of hydrophile-lipophile balance (HLB) of the systems. The maximum solubilization capacity passed through a minimum at psi=0.2. No HLB was obtained at higher psi. The usual fish-tail diagrams were also obtained in temperature-induced phase mapping at fixed W(1) (weight fraction of 1-butanol in total amphiphile). Solubilization capacity and HLB temperature (T(HLB)) decreased with increasing psi at a fixed W(1), the effect being more pronounced for TEG than EG. A correlation between HLB temperature (T(HLB)) and HLB number (N(HLB)) of mixed amphiphiles (Brij-76+Bu) in pseudo-quaternary systems (in the presence of water and partial substitution of water with both NPS) has been established. The novelty of the work with respect to possible applications has been discussed.

Response of sweet orange (Citrus sinensis) to 'Candidatus Liberibacter asiaticus' infection: microscopy and microarray analyses.

PubMed

Kim, Jeong-Soon; Sagaram, Uma Shankar; Burns, Jacqueline K; Li, Jian-Liang; Wang, Nian

2009-01-01

Citrus greening or huanglongbing (HLB) is a devastating disease of citrus. HLB is associated with the phloem-limited fastidious prokaryotic alpha-proteobacterium 'Candidatus Liberibacter spp.' In this report, we used sweet orange (Citrus sinensis) leaf tissue infected with 'Ca. Liberibacter asiaticus' and compared this with healthy controls. Investigation of the host response was examined with citrus microarray hybridization based on 33,879 expressed sequence tag sequences from several citrus species and hybrids. The microarray analysis indicated that HLB infection significantly affected expression of 624 genes whose encoded proteins were categorized according to function. The categories included genes associated with sugar metabolism, plant defense, phytohormone, and cell wall metabolism, as well as 14 other gene categories. The anatomical analyses indicated that HLB bacterium infection caused phloem disruption, sucrose accumulation, and plugged sieve pores. The up-regulation of three key starch biosynthetic genes including ADP-glucose pyrophosphorylase, starch synthase, granule-bound starch synthase and starch debranching enzyme likely contributed to accumulation of starch in HLB-affected leaves. The HLB-associated phloem blockage resulted from the plugged sieve pores rather than the HLB bacterial aggregates since 'Ca. Liberibacter asiaticus' does not form aggregate in citrus. The up-regulation of pp2 gene is related to callose deposition to plug the sieve pores in HLB-affected plants.

Zinc treatment increases the titre of 'Candidatus Liberibacter asiaticus' in huanglongbing-affected citrus plants while affecting the bacterial microbiomes.

PubMed

Zhang, M Q; Guo, Y; Powell, C A; Doud, M S; Yang, C Y; Zhou, H; Duan, Y P

2016-06-01

Huanglongbing (HLB)-affected citrus often display zinc deficiency symptoms. In this study, supplemental zinc was applied to citrus to determine its effect on Candidatus Liberibacter asiaticus (Las) titre, HLB symptoms, and leaf microbiome. HLB-affected citrus were treated with various amounts of zinc. The treatments promoted Las growth and affected microbiomes in citrus leaves. Phylochip(™) -based results indicated that 5475 of over 50 000 known Operational Taxonomic Units (OTUs) in 52 phyla were detected in the midribs of HLB-affected citrus, of which Proteobacteria was the most abundant, followed by Firmicutes and Actinobacteria. In comparison, the microbiomes of zinc-treated diseased plants had overall more OTUs with higher amounts of Proteobacteria, but decreased percentages of Firmicutes and Actinobacteria. In addition, more OTUs of siderophore-producing bacteria were present. Only zinc-sensitive Staphylococcaceae had higher OTU's in the diseased plants without zinc treatments. Although HLB-affected citrus appear zinc deficient, zinc amendments increased the pathogen levels and shifted the microbiome. HLB is currently the most devastating disease of citrus worldwide. Zinc is often applied to HLB-affected citrus due to zinc deficiency symptoms. This study provided new insights into the potential effects of zinc on HLB and the microbial ecology of citrus. © 2016 The Society for Applied Microbiology.

MicroSPE-nanoLC-ESI-MS/MS Using 10-μm-i.d. Silica-Based Monolithic Columns for Proteomics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Quanzhou; Page, Jason S.; Tang, Keqi

2007-01-01

Silica-based monolithic narrow bore capillary columns (25 cm x 10 µm i.d.) with an integrated nanoESI emitter has been developed to provide high quality and robust microSPE-nanoLC-ESI-MS analyses. The integrated nanoESI emitter adds no dead volume to the LC separation, allowing stable electrospray performance to be obtained at flow rates of ~10 nL/min. In an initial application we identified 5510 unique peptides covering 1443 distinct Shewanella oneidensis proteins from a 300 ng tryptic digest sample in a single 4-h LC-MS/MS analysis using a linear ion trap MS (LTQ). We found the use of an integrated monolithic ESI emitter provided enhancedmore » resistance to clogging and good run-to-run reproducibility.« less

The Date Palm Tree Rhizosphere Is a Niche for Plant Growth Promoting Bacteria in the Oasis Ecosystem

PubMed Central

Gtari, Maher; Boudabous, Abdellatif; Daffonchio, Daniele; Ouzari, Hadda-Imene

2015-01-01

In arid ecosystems environmental factors such as geoclimatic conditions and agricultural practices are of major importance in shaping the diversity and functionality of plant-associated bacterial communities. Assessing the influence of such factors is a key to understand (i) the driving forces determining the shape of root-associated bacterial communities and (ii) the plant growth promoting (PGP) services they provide. Desert oasis environment was chosen as model ecosystem where agriculture is possible by the microclimate determined by the date palm cultivation. The bacterial communities in the soil fractions associated with the root system of date palms cultivated in seven oases in Tunisia were assessed by culture-independent and dependent approaches. According to 16S rRNA gene PCR-DGGE fingerprinting, the shapes of the date palm rhizosphere bacterial communities correlate with geoclimatic features along a north-south aridity transect. Despite the fact that the date palm root bacterial community structure was strongly influenced by macroecological factors, the potential rhizosphere services reflected in the PGP traits of isolates screened in vitro were conserved among the different oases. Such services were exerted by the 83% of the screened isolates. The comparable numbers and types of PGP traits indicate their importance in maintaining the plant functional homeostasis despite the different environmental selection pressures. PMID:25866759

The date palm tree rhizosphere is a niche for plant growth promoting bacteria in the oasis ecosystem.

PubMed

Ferjani, Raoudha; Marasco, Ramona; Rolli, Eleonora; Cherif, Hanene; Cherif, Ameur; Gtari, Maher; Boudabous, Abdellatif; Daffonchio, Daniele; Ouzari, Hadda-Imene

2015-01-01

In arid ecosystems environmental factors such as geoclimatic conditions and agricultural practices are of major importance in shaping the diversity and functionality of plant-associated bacterial communities. Assessing the influence of such factors is a key to understand (i) the driving forces determining the shape of root-associated bacterial communities and (ii) the plant growth promoting (PGP) services they provide. Desert oasis environment was chosen as model ecosystem where agriculture is possible by the microclimate determined by the date palm cultivation. The bacterial communities in the soil fractions associated with the root system of date palms cultivated in seven oases in Tunisia were assessed by culture-independent and dependent approaches. According to 16S rRNA gene PCR-DGGE fingerprinting, the shapes of the date palm rhizosphere bacterial communities correlate with geoclimatic features along a north-south aridity transect. Despite the fact that the date palm root bacterial community structure was strongly influenced by macroecological factors, the potential rhizosphere services reflected in the PGP traits of isolates screened in vitro were conserved among the different oases. Such services were exerted by the 83% of the screened isolates. The comparable numbers and types of PGP traits indicate their importance in maintaining the plant functional homeostasis despite the different environmental selection pressures.

Zinc treatment increases the titre of ‘Candidatus Liberibacter asiaticus’ in Huanglongbing-affected citrus plants while affecting the bacterial microbiomes

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB)-affected citrus often display zinc deficiency symptoms. In this study, supplemental zinc was applied to citrus to determine its effect on Candidatus Liberibacter asiaticus (Las) titer, HLB symptoms, and leaf microbiome. HLB-affected citrus were treated with various amounts of zi...

Summaries of research Sessions: 14.10 host resistance

USDA-ARS?s Scientific Manuscript database

The proceedings includes a summary of research reports relating to Citrus HLB-resistance. A number of research organizations are exploring resistance to hunaglongbing (HLB) in existing citrus varieties or citrus relatives, identifying transgenes that may provide resistance to HLB and other diseases,...

Effects on Asian Citrus Psyllid (Diaphorina citri Kuwayama) feeding behavior of fenpropathrin and chlorpyrifos within 24 hours of application

USDA-ARS?s Scientific Manuscript database

Huanglongbing (HLB), also known as citrus greening disease, is one of the most destructive diseases affecting citrus production. The phloem-limited bacterium associated with HLB is transmitted by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae). One component of HLB managem...

Analysis of ketamine and norketamine in urine by automatic solid-phase extraction (SPE) and positive ion chemical ionization-gas chromatography-mass spectrometry (PCI-GC-MS).

PubMed

Kim, Eun-mi; Lee, Ju-seon; Choi, Sang-kil; Lim, Mi-ae; Chung, Hee-sun

2008-01-30

Ketamine (KT) is widely abused for hallucination and also misused as a "date-rape" drug in recent years. An analytical method using positive ion chemical ionization-gas chromatography-mass spectrometry (PCI-GC-MS) with an automatic solid-phase extraction (SPE) apparatus was studied for the determination of KT and its major metabolite, norketamine (NK), in urine. Six ketamine suspected urine samples were provided by the police. For the research of KT metabolism, KT was administered to SD rats by i.p. at a single dose of 5, 10 and 20mg/kg, respectively, and urine samples were collected 24, 48 and 72 h after administration. For the detection of KT and NK, urine samples were extracted on an automatic SPE apparatus (RapidTrace, Zymark) with mixed mode type cartridge, Drug-Clean (200 mg, Alltech). The identification of KT and NK was by PCI-GC-MS. m/z238 (M+1), 220 for KT, m/z 224 (M+1), 207 for NK and m/z307 (M+1) for Cocaine-D(3) as internal standard were extracted from the full-scan mass spectrum and the underlined ions were used for quantitation. Extracted calibration curves were linear from 50 to 1000 ng/mL for KT and NK with correlation coefficients exceeding 0.99. The limit of detection (LOD) was 25 ng/mL for KT and NK. The limit of quantitation (LOQ) was 50 ng/mL for KT and NK. The recoveries of KT and NK at three different concentrations (86, 430 and 860 ng/mL) were 53.1 to 79.7% and 45.7 to 83.0%, respectively. The intra- and inter-day run precisions (CV) for KT and NK were less than 15.0%, and the accuracies (bias) for KT and NK were also less than 15% at the three different concentration levels (86, 430 and 860 ng/mL). The analytical method was also applied to real six KT suspected urine specimens and KT administered rat urines, and the concentrations of KT and NK were determined. Dehydronorketamine (DHNK) was also confirmed in these urine samples, however the concentration of DHNK was not calculated. SPE is simple, and needs less organic solvent than liquid

Determination of etoxazole residues in fruits and vegetables by SPE clean-up and HPLC-DAD.

PubMed

Malhat, Farag; Badawy, Hany; Barakat, Dalia; Saber, Ayman

2013-01-01

A method for determination of etoxazole residues in apples, strawberries and green beans was developed and validated. The analyte was extracted with acetonitrile from foodstuff and a charcoal-celite cartridge was used for clean-up of raw extracts. Reversed phase high performance liquid chromatography with photodiode array detector (HPLC-DAD) was used for the determination and quantification of etoxazole residues in the studied samples. The calibration graphs of etoxazole in a solvent or three blank matrixes were linear within the tested intervals 0.01-2 mg L(-1), with correlation coefficient of determination >0.999. The combined solid phase extraction (SPE) clean-up and the chromatographic method steps were sensitive and reliable for simultaneous determination of etoxazole residues in the studied samples. The average recoveries of etoxazole in the tested foodstuffs were between 93.4 to 102% at spiking levels of 0.01, 0.10, and 0.50 mg kg(-1), with relative standard deviations ranging from 2.8 to 4.7%, in agreement with directives for method validation in residue analyses. The limit of detection (LOD) of the HPLC-DAD system was 100 pg. The limit of quantification of the entire method was 0.01 mg kg(-1).

Gene expression in Citrus sinensis fruit tissues harvested from huanglongbing-infected trees: comparison with girdled fruit.

PubMed

Liao, Hui-Ling; Burns, Jacqueline K

2012-05-01

Distribution of viable Candidatus Liberibacter asiaticus (CaLas) in sweet orange fruit and leaves ('Hamlin' and 'Valencia') and transcriptomic changes associated with huanglongbing (HLB) infection in fruit tissues are reported. Viable CaLas was present in most fruit tissues tested in HLB trees, with the highest titre detected in vascular tissue near the calyx abscission zone. Transcriptomic changes associated with HLB infection were analysed in flavedo (FF), vascular tissue (VT), and juice vesicles (JV) from symptomatic (SY), asymptomatic (AS), and healthy (H) fruit. In SY 'Hamlin', HLB altered the expression of more genes in FF and VT than in JV, whereas in SY 'Valencia', the number of genes whose expression was changed by HLB was similar in these tissues. The expression of more genes was altered in SY 'Valencia' JV than in SY 'Hamlin' JV. More genes were also affected in AS 'Valencia' FF and VT than in AS 'Valencia' JV. Most genes whose expression was changed by HLB were classified as transporters or involved in carbohydrate metabolism. Physiological characteristics of HLB-infected and girdled fruit were compared to differentiate between HLB-specific and carbohydrate metabolism-related symptoms. SY and girdled fruit were smaller than H and ungirdled fruit, respectively, with poor juice quality. However, girdling did not cause misshapen fruit or differential peel coloration. Quantitative PCR analysis indicated that many selected genes changed their expression significantly in SY flavedo but not in girdled flavedo. Mechanisms regulating development of HLB symptoms may lie in the host disease response rather than being a direct consequence of carbohydrate starvation.

Control of Citrus Huanglongbing via Trunk Injection of Plant Defense Activators and Antibiotics.

PubMed

Hu, J; Jiang, J; Wang, N

2018-02-01

Citrus huanglongbing (HLB) or greening is a devastating disease of citrus worldwide and no effective control measure is currently available. Plant defense activators environmentally friendly compounds capable of inducing resistance against many plant pathogens. Earlier studies showed that foliar spray of plant defense inducers could slow down HLB disease progress. In this study, eight plant defense activators and three antibiotics were evaluated in three field trials for their effect to control HLB by trunk injection of young and mature sweet orange trees. Results showed that four trunk injections of several activators, including salicylic acid, oxalic acid, acibenzolar-S-methyl, and potassium phosphate, provided significant control of HLB by suppressing 'Candidatus Liberibacter asiaticus' titer and disease progress. Trunk injection of penicillin, streptomycin, and oxytetracycline hydrochloride resulted in excellent control of HLB. In general, antibiotics were more effective in reduction of 'Ca. L. asiaticus' titer and HLB symptom expressions than plant defense activators. These treatments also resulted in increased yield and better fruit quality. Injection of both salicylic acid and acibenzolar-S-methyl led to significant induction of pathogenesis-related (PR) genes PR-1 and PR-2 genes. Meanwhile, injection of either potassium phosphate or oxalic acid resulted in significant induction of PR-2 or PR-15 gene expression, respectively. These results suggested that HLB diseased trees remained inducible for systemic acquired resistance under field conditions. In summary, this study presents information regarding controlling HLB via trunk injection of plant defense activators and antibiotics, which helps citrus growers in decision making regarding developing an effective HLB management program.

Small RNA profiling reveals phosphorus deficiency as a contributing factor in symptom expression for citrus huanglongbing disease.

PubMed

Zhao, Hongwei; Sun, Ruobai; Albrecht, Ute; Padmanabhan, Chellappan; Wang, Airong; Coffey, Michael D; Girke, Thomas; Wang, Zonghua; Close, Timothy J; Roose, Mikeal; Yokomi, Raymond K; Folimonova, Svetlana; Vidalakis, Georgios; Rouse, Robert; Bowman, Kim D; Jin, Hailing

2013-03-01

Huanglongbing (HLB) is a devastating citrus disease that is associated with bacteria of the genus 'Candidatus Liberibacter' (Ca. L.). Powerful diagnostic tools and management strategies are desired to control HLB. Host small RNAs (sRNA) play a vital role in regulating host responses to pathogen infection and are used as early diagnostic markers for many human diseases, including cancers. To determine whether citrus sRNAs regulate host responses to HLB, sRNAs were profiled from Citrus sinensis 10 and 14 weeks post grafting with Ca. L. asiaticus (Las)-positive or healthy tissue. Ten new microRNAs (miRNAs), 76 conserved miRNAs, and many small interfering RNAs (siRNAs) were discovered. Several miRNAs and siRNAs were highly induced by Las infection, and can be potentially developed into early diagnosis markers of HLB. miR399, which is induced by phosphorus starvation in other plant species, was induced specifically by infection of Las but not Spiroplasma citri that causes citrus stubborn-a disease with symptoms similar to HLB. We found a 35% reduction of phosphorus in Las-positive citrus trees compared to healthy trees. Applying phosphorus oxyanion solutions to HLB-positive sweet orange trees reduced HLB symptom severity and significantly improved fruit production during a 3-year field trial in south-west Florida. Our molecular, physiological, and field data suggest that phosphorus deficiency is linked to HLB disease symptomology.

The SpeX Prism Library Analysis Toolkit: Design Considerations and First Results

NASA Astrophysics Data System (ADS)

Burgasser, Adam J.; Aganze, Christian; Escala, Ivana; Lopez, Mike; Choban, Caleb; Jin, Yuhui; Iyer, Aishwarya; Tallis, Melisa; Suarez, Adrian; Sahi, Maitrayee

2016-01-01

Various observational and theoretical spectral libraries now exist for galaxies, stars, planets and other objects, which have proven useful for classification, interpretation, simulation and model development. Effective use of these libraries relies on analysis tools, which are often left to users to develop. In this poster, we describe a program to develop a combined spectral data repository and Python-based analysis toolkit for low-resolution spectra of very low mass dwarfs (late M, L and T dwarfs), which enables visualization, spectral index analysis, classification, atmosphere model comparison, and binary modeling for nearly 2000 library spectra and user-submitted data. The SpeX Prism Library Analysis Toolkit (SPLAT) is being constructed as a collaborative, student-centered, learning-through-research model with high school, undergraduate and graduate students and regional science teachers, who populate the database and build the analysis tools through quarterly challenge exercises and summer research projects. In this poster, I describe the design considerations of the toolkit, its current status and development plan, and report the first published results led by undergraduate students. The combined data and analysis tools are ideal for characterizing cool stellar and exoplanetary atmospheres (including direct exoplanetary spectra observations by Gemini/GPI, VLT/SPHERE, and JWST), and the toolkit design can be readily adapted for other spectral datasets as well.This material is based upon work supported by the National Aeronautics and Space Administration under Grant No. NNX15AI75G. SPLAT code can be found at https://github.com/aburgasser/splat.

GC-MS analysis of headspace and liquid extracts for metabolomic differentiation of citrus Huanglongbing and zinc deficiency in leaves of 'Valencia' sweet orange from commercial groves.

PubMed

Cevallos-Cevallos, Juan Manuel; García-Torres, Rosalía; Etxeberria, Edgardo; Reyes-De-Corcuera, José Ignacio

2011-01-01

Citrus Huanglongbing (HLB) is considered the most destructive citrus disease worldwide. Symptoms-based detection of HLB is difficult due to similarities with zinc deficiency. To find metabolic differences between leaves from HLB-infected, zinc-deficient, and healthy 'Valencia' orange trees by using GC-MS based metabolomics. Analysis based on GC-MS methods for untargeted metabolite analysis of citrus leaves was developed and optimized. Sample extracts from healthy, zinc deficient, or HLB-infected sweet orange leaves were submitted to headspace solid phase micro-extraction (SPME) and derivatization treatments prior to GC-MS analysis. Principal components analysis achieved correct classification of all the derivatized liquid extracts. Analysis of variance revealed 6 possible biomarkers for HLB, of which 5 were identified as proline, β-elemene, (-)trans- caryophyllene, and α-humulene. Significant (P < 0.05) differences in oxo-butanedioic acid, arabitol, and neo-inositol were exclusively detected in samples from plants with zinc deficiency. Levels of isocaryophyllen, α-selinene, β-selinene, and fructose were significantly (P < 0.05) different in healthy leaves only. Results suggest the potential of using identified HLB biomarkers for rapid differentiation of HLB from zinc deficiency. Copyright © 2010 John Wiley & Sons, Ltd.