Sequential Fuzzy Diagnosis Method for Motor Roller Bearing in Variable Operating Conditions Based on Vibration Analysis

PubMed Central

Li, Ke; Ping, Xueliang; Wang, Huaqing; Chen, Peng; Cao, Yi

2013-01-01

A novel intelligent fault diagnosis method for motor roller bearings which operate under unsteady rotating speed and load is proposed in this paper. The pseudo Wigner-Ville distribution (PWVD) and the relative crossing information (RCI) methods are used for extracting the feature spectra from the non-stationary vibration signal measured for condition diagnosis. The RCI is used to automatically extract the feature spectrum from the time-frequency distribution of the vibration signal. The extracted feature spectrum is instantaneous, and not correlated with the rotation speed and load. By using the ant colony optimization (ACO) clustering algorithm, the synthesizing symptom parameters (SSP) for condition diagnosis are obtained. The experimental results shows that the diagnostic sensitivity of the SSP is higher than original symptom parameter (SP), and the SSP can sensitively reflect the characteristics of the feature spectrum for precise condition diagnosis. Finally, a fuzzy diagnosis method based on sequential inference and possibility theory is also proposed, by which the conditions of the machine can be identified sequentially as well. PMID:23793021

Sequential microfluidic droplet processing for rapid DNA extraction.

PubMed

Pan, Xiaoyan; Zeng, Shaojiang; Zhang, Qingquan; Lin, Bingcheng; Qin, Jianhua

2011-11-01

This work describes a novel droplet-based microfluidic device, which enables sequential droplet processing for rapid DNA extraction. The microdevice consists of a droplet generation unit, two reagent addition units and three droplet splitting units. The loading/washing/elution steps required for DNA extraction were carried out by sequential microfluidic droplet processing. The movement of superparamagnetic beads, which were used as extraction supports, was controlled with magnetic field. The microdevice could generate about 100 droplets per min, and it took about 1 min for each droplet to perform the whole extraction process. The extraction efficiency was measured to be 46% for λ-DNA, and the extracted DNA could be used in subsequent genetic analysis such as PCR, demonstrating the potential of the device for fast DNA extraction. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Faye, Sherry A.; Richards, Jason M.; Gallardo, Athena M.

Sequential extraction is a useful technique for assessing the potential to leach actinides from soils; however, current literature lacks uniformity in experimental details, making direct comparison of results impossible. This work continued development toward a standardized five-step sequential extraction protocol by analyzing extraction behaviors of 232Th, 238U, 239,240Pu and 241Am from lake and ocean sediment reference materials. Results produced a standardized procedure after creating more defined reaction conditions to improve method repeatability. A NaOH fusion procedure is recommended following sequential leaching for the complete dissolution of insoluble species.

SEQUENTIAL EXTRACTIONS FOR PARTITIONING OF ARSENIC ON HYDROUS IRON OXIDES AND IRON SULFIDES

EPA Science Inventory

The objective of this study was to use model solids to test solutions designed to extract arsenic from relatively labile solid phase fractions. The use of sequential extractions provides analytical constraints on the identification of mineral phases that control arsenic mobility...

Phenolic content and antioxidant activity of Hibiscus cannabinus L. seed extracts after sequential solvent extraction.

PubMed

Yusri, Noordin Mohd; Chan, Kim Wei; Iqbal, Shahid; Ismail, Maznah

2012-10-25

A sequential solvent extraction scheme was employed for the extraction of antioxidant compounds from kenaf (Hibiscus cannabinus L.) seeds. Yield of extracts varied widely among the solvents and was the highest for hexane extract (16.6% based on dry weight basis), while water extract exhibited the highest total phenolic content (18.78 mg GAE/g extract), total flavonoid content (2.49 mg RE/g extract), and antioxidant activities (p < 0.05). DPPH and hydroxyl radical scavenging, β-carotene bleaching, metal chelating activity, ferric thiocyanate and thiobarbituric acid reactive substances assays were employed to comprehensively assess the antioxidant potential of different solvent extracts prepared sequentially. Besides water, methanolic extract also exhibited high retardation towards the formation of hydroperoxides and thiobarbituric acid reactive substances in the total antioxidant activity tests (p < 0.05). As conclusion, water and methanol extracts of kenaf seed may potentially serve as new sources of antioxidants for food and nutraceutical applications.

Evaluating specificity of sequential extraction for chemical forms of lead in artificially-contaminated and field-contaminated soils.

PubMed

Tai, Yiping; McBride, Murray B; Li, Zhian

2013-03-30

In the present study, we evaluated a commonly employed modified Bureau Communautaire de Référence (BCR test) 3-step sequential extraction procedure for its ability to distinguish forms of solid-phase Pb in soils with different sources and histories of contamination. When the modified BCR test was applied to mineral soils spiked with three forms of Pb (pyromorphite, hydrocerussite and nitrate salt), the added Pb was highly susceptible to dissolution in the operationally-defined "reducible" or "oxide" fraction regardless of form. When three different materials (mineral soil, organic soil and goethite) were spiked with soluble Pb nitrate, the BCR sequential extraction profiles revealed that soil organic matter was capable of retaining Pb in more stable and acid-resistant forms than silicate clay minerals or goethite. However, the BCR sequential extraction for field-collected soils with known and different sources of Pb contamination was not sufficiently discriminatory in the dissolution of soil Pb phases to allow soil Pb forms to be "fingerprinted" by this method. It is concluded that standard sequential extraction procedures are probably not very useful in predicting lability and bioavailability of Pb in contaminated soils. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimizing Standard Sequential Extraction Protocol With Lake And Ocean Sediments

EPA Science Inventory

The environmental mobility/availability behavior of radionuclides in soils and sediments depends on their speciation. Experiments have been carried out to develop a simple but robust radionuclide sequential extraction method for identification of radionuclide partitioning in sed...

Collaborative Filtering Based on Sequential Extraction of User-Item Clusters

NASA Astrophysics Data System (ADS)

Honda, Katsuhiro; Notsu, Akira; Ichihashi, Hidetomo

Collaborative filtering is a computational realization of “word-of-mouth” in network community, in which the items prefered by “neighbors” are recommended. This paper proposes a new item-selection model for extracting user-item clusters from rectangular relation matrices, in which mutual relations between users and items are denoted in an alternative process of “liking or not”. A technique for sequential co-cluster extraction from rectangular relational data is given by combining the structural balancing-based user-item clustering method with sequential fuzzy cluster extraction appraoch. Then, the tecunique is applied to the collaborative filtering problem, in which some items may be shared by several user clusters.

Separation of chemical groups from bio-oil aqueous phase via sequential organic solvent extraction

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

Ren, Shoujie; Ye, Philip; Borole, Abhijeet P

Bio-oil aqueous phase contains a considerable amount of furans, alcohols, ketones, aldehydes and phenolics besides the major components of organic acids and anhydrosugars. The complexity of bio-oil aqueous phase limits its efficient utilization. To improve the efficiency of bio-oil biorefinery, this study focused on the separation of chemical groups from bio-oil aqueous phase via sequential organic solvent extractions. Due to their high recoverability and low solubility in water, four solvents (hexane, petroleum ether, chloroform, and ethyl acetate) with different polarities were evaluated, and the optimum process conditions for chemical extraction were determined. Chloroform had high extraction efficiency for furans, phenolics,more » and ketones. In addition to these chemical groups, ethyl acetate had high extraction efficiency for organic acids. The sequential extraction by using chloroform followed by ethyl acetate rendered that 62.2 wt.% of original furans, ketones, alcohols, and phenolics were extracted to chloroform, over 62 wt.% acetic acid was extracted to ethyl acetate, resulting in a high concentration of levoglucosan (~53.0 wt.%) in the final aqueous phase. Chemicals separated via the sequential extraction could be used as feedstocks in biorefinery using processes such as catalytic upgrading of furans and phenolics to hydrocarbons, fermentation of levoglucosan to produce alcohols and diols, and hydrogen production from organic acids via microbial electrolysis.« less

Separation of chemical groups from bio-oil aqueous phase via sequential organic solvent extraction

DOE PAGES

Ren, Shoujie; Ye, Philip; Borole, Abhijeet P

2017-01-05

Bio-oil aqueous phase contains a considerable amount of furans, alcohols, ketones, aldehydes and phenolics besides the major components of organic acids and anhydrosugars. The complexity of bio-oil aqueous phase limits its efficient utilization. To improve the efficiency of bio-oil biorefinery, this study focused on the separation of chemical groups from bio-oil aqueous phase via sequential organic solvent extractions. Due to their high recoverability and low solubility in water, four solvents (hexane, petroleum ether, chloroform, and ethyl acetate) with different polarities were evaluated, and the optimum process conditions for chemical extraction were determined. Chloroform had high extraction efficiency for furans, phenolics,more » and ketones. In addition to these chemical groups, ethyl acetate had high extraction efficiency for organic acids. The sequential extraction by using chloroform followed by ethyl acetate rendered that 62.2 wt.% of original furans, ketones, alcohols, and phenolics were extracted to chloroform, over 62 wt.% acetic acid was extracted to ethyl acetate, resulting in a high concentration of levoglucosan (~53.0 wt.%) in the final aqueous phase. Chemicals separated via the sequential extraction could be used as feedstocks in biorefinery using processes such as catalytic upgrading of furans and phenolics to hydrocarbons, fermentation of levoglucosan to produce alcohols and diols, and hydrogen production from organic acids via microbial electrolysis.« less

Instant controlled pressure drop technology and ultrasound assisted extraction for sequential extraction of essential oil and antioxidants.

PubMed

Allaf, Tamara; Tomao, Valérie; Ruiz, Karine; Chemat, Farid

2013-01-01

The instant controlled pressure drop (DIC) technology enabled both the extraction of essential oil and the expansion of the matrix itself which improved solvent extraction. The sequential use of DIC and Ultrasound Assisted Extraction (UAE) triggered complementary actions materialized by supplementary effects. We visualized these combination impacts by comparing them to standard techniques: Hydrodistillation (HD) and Solvent Extraction (SE). First, the extraction of orange peel Essential Oils (EO) was achieved by HD during 4h and DIC process (after optimization) during 2 min; EO yields was 1.97 mg/g dry material (dm) with HD compared to 16.57 mg/g d m with DIC. Second, the solid residue was recovered to extract antioxidant compounds (naringin and hesperidin) by SE and UAE. Scanning electron microscope showed that after HD the recovered solid shriveled as opposite to DIC treatment which expanded the product structure. HPLC analyses showed that the best kinetics and yields of naringin and hesperidin extraction was when DIC and UAE are combined. Indeed, after 1h of extraction, DIC treated orange peels with UAE were 0.825 ± 1.6 × 10(-2)g/g of dry material (dm) for hesperidin and 6.45 × 10(-2) ± 2.3 × 10(-4)g/g d m for naringin compared to 0.64 ± 2.7 × 10(-2)g/g of dry material (dm) and 5.7 × 10(-2) ± 1.6 × 10(-3)g/g d m, respectively with SE. By combining DIC to UAE, it was possible to enhance kinetics and yields of antioxidant extraction. Copyright © 2012 Elsevier B.V. All rights reserved.

Understanding Human Motion Skill with Peak Timing Synergy

NASA Astrophysics Data System (ADS)

Ueno, Ken; Furukawa, Koichi

The careful observation of motion phenomena is important in understanding the skillful human motion. However, this is a difficult task due to the complexities in timing when dealing with the skilful control of anatomical structures. To investigate the dexterity of human motion, we decided to concentrate on timing with respect to motion, and we have proposed a method to extract the peak timing synergy from multivariate motion data. The peak timing synergy is defined as a frequent ordered graph with time stamps, which has nodes consisting of turning points in motion waveforms. A proposed algorithm, PRESTO automatically extracts the peak timing synergy. PRESTO comprises the following 3 processes: (1) detecting peak sequences with polygonal approximation; (2) generating peak-event sequences; and (3) finding frequent peak-event sequences using a sequential pattern mining method, generalized sequential patterns (GSP). Here, we measured right arm motion during the task of cello bowing and prepared a data set of the right shoulder and arm motion. We successfully extracted the peak timing synergy on cello bowing data set using the PRESTO algorithm, which consisted of common skills among cellists and personal skill differences. To evaluate the sequential pattern mining algorithm GSP in PRESTO, we compared the peak timing synergy by using GSP algorithm and the one by using filtering by reciprocal voting (FRV) algorithm as a non time-series method. We found that the support is 95 - 100% in GSP, while 83 - 96% in FRV and that the results by GSP are better than the one by FRV in the reproducibility of human motion. Therefore we show that sequential pattern mining approach is more effective to extract the peak timing synergy than non-time series analysis approach.

INVESTIGATION OF ARSENIC SPECIATION ON DRINKING WATER TREATMENT MEDIA UTILIZING AUTOMATED SEQUENTIAL CONTINUOUS FLOW EXTRACTION WITH IC-ICP-MS DETECTION

EPA Science Inventory

Three treatment media, used for the removal of arsenic from drinking water, were sequentially extracted using 10mM MgCl2 (pH 8), 10mM NaH2PO4 (pH 7) followed by 10mM (NH4)2C2O4 (pH 3). The media were extracted using an on-line automated continuous extraction system which allowed...

Fractionation of trace elements in agricultural soils using ultrasound assisted sequential extraction prior to inductively coupled plasma mass spectrometric determination.

PubMed

Matong, Joseph M; Nyaba, Luthando; Nomngongo, Philiswa N

2016-07-01

The main objectives of this study were to determine the concentration of fourteen trace elements and to investigate their distribution as well as a contamination levels in selected agricultural soils. An ultrasonic assisted sequential extraction procedure derived from three-step BCR method was used for fractionation of trace elements. The total concentration of trace elements in soil samples was obtained by total digestion method in soil samples with aqua regia. The results of the extractable fractions revealed that most of the target trace elements can be transferred to the human being through the food chain, thus leading to serious human health. Enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (CF), risk assessment code (RAC) and individual contamination factors (ICF) were used to assess the environmental impacts of trace metals in soil samples. The EF revealed that Cd was enriched by 3.1-7.2 (except in Soil 1). The Igeo results showed that the soils in the study area was moderately contaminated with Fe, and heavily to extremely polluted with Cd. The soil samples from the unplanted field was found to have highest contamination factor for Cd and lowest for Pb. Soil 3 showed a high risk for Tl and Cd with RAC values of greater than or equal to 50%. In addition, Fe, Ni, Cu, V, As, Mo (except Soil 2), Sb and Pb posed low environmental risk. The modified BCR sequential extraction method provided more information about mobility and environmental implication of studied trace elements in the study area. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sequential extraction of metals from mixed and digested sludge from aerobic WWTPs sited in the south of Spain

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

Alonso, E.; Aparicio, I.; Santos, J.L.

2009-01-15

The content of heavy metals is the major limitation to the application of sewage sludge in soil. However, assessment of the pollution by total metal determination does not reveal the true environmental impact. It is necessary to apply sequential extraction techniques to obtain suitable information about their bioavailability or toxicity. In this paper, sequential extraction of metals from sludge before and after aerobic digestion was applied to sludge from five WWTPs in southern Spain to obtain information about the influence of the digestion treatment in the concentration of the metals. The percentage of each metal as residual, oxidizable, reducible andmore » exchangeable form was calculated. For this purpose, sludge samples were collected from two different points of the plants, namely, sludge from the mixture (primary and secondary sludge) tank (mixed sludge, MS) and the digested-dewatered sludge (final sludge, FS). Heavy metals, Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Ti and Zn, were extracted following the sequential extraction scheme proposed by the Standards, Measurements and Testing Programme of the European Commission and determined by inductively-coupled plasma atomic emission spectrometry. The total concentration of heavy metals in the measured sludge samples did not exceed the limits set out by European legislation and were mainly associated with the two less-available fractions (27-28% as oxidizable metal and 44-50% as residual metal). However, metals as Co (64% in MS and 52% in FS samples), Mn (82% in MS and 79% in FS), Ni (32% in MS and 26% in FS) and Zn (79% in MS and 62% in FS) were present at important percentages as available forms. In addition, results showed a clear increase of the concentration of metals after sludge treatment in the proportion of two less-available fractions (oxidizable and residual metal)« less

Sequential extraction of metals from mixed and digested sludge from aerobic WWTPs sited in the south of Spain.

PubMed

Alonso, E; Aparicio, I; Santos, J L; Villar, P; Santos, A

2009-01-01

The content of heavy metals is the major limitation to the application of sewage sludge in soil. However, assessment of the pollution by total metal determination does not reveal the true environmental impact. It is necessary to apply sequential extraction techniques to obtain suitable information about their bioavailability or toxicity. In this paper, sequential extraction of metals from sludge before and after aerobic digestion was applied to sludge from five WWTPs in southern Spain to obtain information about the influence of the digestion treatment in the concentration of the metals. The percentage of each metal as residual, oxidizable, reducible and exchangeable form was calculated. For this purpose, sludge samples were collected from two different points of the plants, namely, sludge from the mixture (primary and secondary sludge) tank (mixed sludge, MS) and the digested-dewatered sludge (final sludge, FS). Heavy metals, Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Ti and Zn, were extracted following the sequential extraction scheme proposed by the Standards, Measurements and Testing Programme of the European Commission and determined by inductively-coupled plasma atomic emission spectrometry. The total concentration of heavy metals in the measured sludge samples did not exceed the limits set out by European legislation and were mainly associated with the two less-available fractions (27-28% as oxidizable metal and 44-50% as residual metal). However, metals as Co (64% in MS and 52% in FS samples), Mn (82% in MS and 79% in FS), Ni (32% in MS and 26% in FS) and Zn (79% in MS and 62% in FS) were present at important percentages as available forms. In addition, results showed a clear increase of the concentration of metals after sludge treatment in the proportion of two less-available fractions (oxidizable and residual metal).

Sequential injection analysis with chemiluminescence detection for rapid monitoring of commercial Calendula officinalis extractions.

PubMed

Hughes, Rachel R; Scown, David; Lenehan, Claire E

2015-01-01

Plant extracts containing high levels of antioxidants are desirable due to their reported health benefits. Most techniques capable of determining the antioxidant activity of plant extracts are unsuitable for rapid at-line analysis as they require extensive sample preparation and/or long analysis times. Therefore, analytical techniques capable of real-time or pseudo real-time at-line monitoring of plant extractions, and determination of extraction endpoints, would be useful to manufacturers of antioxidant-rich plant extracts. To develop a reliable method for the rapid at-line extraction monitoring of antioxidants in plant extracts. Calendula officinalis extracts were prepared from dried flowers and analysed for antioxidant activity using sequential injection analysis (SIA) with chemiluminescence (CL) detection. The intensity of CL emission from the reaction of acidic potassium permanganate with antioxidants within the extract was used as the analytical signal. The SIA-CL method was applied to monitor the extraction of C. officinalis over the course of a batch extraction to determine the extraction endpoint. Results were compared with those from ultra high performance liquid chromatography (UHPLC). Pseudo real-time, at-line monitoring showed the level of antioxidants in a batch extract of Calendula officinalis plateaued after 100 min of extraction. These results correlated well with those of an offline UHPLC study. SIA-CL was found to be a suitable method for pseudo real-time monitoring of plant extractions and determination of extraction endpoints with respect to antioxidant concentrations. The method was applied at-line in the manufacturing industry. Copyright © 2015 John Wiley & Sons, Ltd.

INVESTIGATION OF SEQUENTIAL AND ENZYMATIC EXTRACTION OF ARSENIC FROM DRINKING WATER DISTRIBUTION SOLIDS WITH ICP-MS

EPA Science Inventory

A sequential extraction approach was utilized to estimate the distribution of arsenite [As(III)] and arsenate [As(V)] on iron oxide/hydroxide solids obtained from drinking water distribution systems. The arsenic (As) associated with these solids can be segregated into three oper...

ASSESSMENT OF A SEQUENTIAL EXTRACTION PROCEDURE FOR PERTURBED LEAD-CONTAMINATED SAMPLES WITH AND WITHOUT PHOSPHOROUS AMENDMENTS

EPA Science Inventory

Sequential extraction procedures are used to determine the solid-phase association in which elements of interest exist in soil and sediment matrices. Foundational work by Tessier et al. (1) has found widespread acceptance and has worked tolerably as an operational definition for...

Surface characterization of cottonseed meal products by SEM, SEM-EDS, XRD and XPS analysis

USDA-ARS?s Scientific Manuscript database

The utilization of cottonseed meal as a valuable industrial feedstock needs to be exploited. We have recently produced water-washed cottonseed meal, total cottonseed protein, sequentially extracted water- and alkali-soluble proteins, and two residues after the total and sequential protein extraction...

The utilization of modified BCR three-step sequential extraction procedure for the fractionation of Cd, Cr, Cu, Ni, Pb and Zn in soil reference materials of different origins.

PubMed

Zemberyová, Mária; Barteková, Jana; Hagarová, Ingrid

2006-12-15

A modified three-step sequential extraction procedure for the fractionation of heavy metals, proposed by the Commission of the European Communities Bureau of Reference (BCR) has been applied to the Slovak reference materials of soils (soil orthic luvisols, soil rendzina and soil eutric cambisol), which represent pedologically different types of soils in Slovakia. Analyses were carried out by flame or electrothermal atomic absorption spectrometry (FAAS or ETAAS). The fractions extracted were: exchangeable (extraction step 1), reducible-iron/manganese oxides (extraction step 2), oxidizable-organic matter and sulfides (extraction step 3). The sum of the element contents in the three fractions plus aqua-regia extractable content of the residue was compared to the aqua-regia extractable content of the elements in the origin soils. The accuracy obtained by comparing the determined contents of the elements with certified values, using BCR CRM 701, certified for the extractable contents (mass fractions) of Cd, Cr, Cu, Ni, Pb and Zn in sediment following a modified BCR-three step sequential extraction procedure, was found to be satisfactory.

Heavy metal extractable forms in sludge from wastewater treatment plants.

PubMed

Alvarez, E Alonso; Mochón, M Callejón; Jiménez Sánchez, J C; Ternero Rodríguez, M

2002-05-01

The analysis of heavy metals is a very important task to assess the potential environmental and health risk associated with the sludge coming from wastewater treatment plants (WWTPs). However, it is widely accepted that the determination of total elements does not give an accurate estimation of the potential environmental impact. So, it is necessary to apply sequential extraction techniques to obtain a suitable information about their bioavailability or toxicity. In this paper, a sequential extraction scheme according to the BCR's guidelines was applied to sludge samples collected from each sludge treatment step of five municipal activated sludge plants. Al. Cd, Co, Cu, Cr, Fe, Mn, Hg, Mo, Ni, Pb, Ti and Zn were determined in the sludge extracts by inductively coupled plasma atomic emission spectrometry. In relation to current international legislation for the use of sludge for agricultural purposes none of metal concentrations exceeded maximum permitted levels. In most of the metal elements under considerations, results showed a clear rise along the sludge treatment in the proportion of two less-available fractions (oxidizable metal and residual metal).

The sequential structure of brain activation predicts skill.

PubMed

Anderson, John R; Bothell, Daniel; Fincham, Jon M; Moon, Jungaa

2016-01-29

In an fMRI study, participants were trained to play a complex video game. They were scanned early and then again after substantial practice. While better players showed greater activation in one region (right dorsal striatum) their relative skill was better diagnosed by considering the sequential structure of whole brain activation. Using a cognitive model that played this game, we extracted a characterization of the mental states that are involved in playing a game and the statistical structure of the transitions among these states. There was a strong correspondence between this measure of sequential structure and the skill of different players. Using multi-voxel pattern analysis, it was possible to recognize, with relatively high accuracy, the cognitive states participants were in during particular scans. We used the sequential structure of these activation-recognized states to predict the skill of individual players. These findings indicate that important features about information-processing strategies can be identified from a model-based analysis of the sequential structure of brain activation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chemical investigations of male and female leaf extracts from Schinus molle L.

PubMed

Garzoli, Stefania; Laghezza Masci, Valentina; Turchetti, Giovanni; Pesci, Lorenzo; Tiezzi, Antonio; Ovidi, Elisa

2018-05-29

The pepper-tree Schinus molle is an evergreen ornamental plant with various and diversified list of medical uses. In this article we analysed the chemical composition of male and female leaves of this plant during the off-flowering and flowering seasons. The leaf extracts were obtained by using a sequential extraction with solvents of different polarities and the chemical composition was investigated by GC-MS. The results showed a total of twenty-three components, in which elemol is the most abundant constituent followed by bicyclogermacrene, γ-eudesmol, α-eudesmol, β-eudesmol and isocalamendiol. The petroleum ether and diethyl ether extracts from male and female flowering and off-flowering leaves consisted of sesquiterpene hydrocarbons as a major constituent followed by monoterpene hydrocarbons, while the acetone extracts showed a different composition. The obtained results show differences in the chemical composition between male and female and flowering and not flowering.

Classification of epileptic EEG signals based on simple random sampling and sequential feature selection.

PubMed

Ghayab, Hadi Ratham Al; Li, Yan; Abdulla, Shahab; Diykh, Mohammed; Wan, Xiangkui

2016-06-01

Electroencephalogram (EEG) signals are used broadly in the medical fields. The main applications of EEG signals are the diagnosis and treatment of diseases such as epilepsy, Alzheimer, sleep problems and so on. This paper presents a new method which extracts and selects features from multi-channel EEG signals. This research focuses on three main points. Firstly, simple random sampling (SRS) technique is used to extract features from the time domain of EEG signals. Secondly, the sequential feature selection (SFS) algorithm is applied to select the key features and to reduce the dimensionality of the data. Finally, the selected features are forwarded to a least square support vector machine (LS_SVM) classifier to classify the EEG signals. The LS_SVM classifier classified the features which are extracted and selected from the SRS and the SFS. The experimental results show that the method achieves 99.90, 99.80 and 100 % for classification accuracy, sensitivity and specificity, respectively.

Phosphorus Speciation of Sequential Extracts of Organic Amendments using NMR Spectroscopy

NASA Astrophysics Data System (ADS)

Akinremi, O.

2009-04-01

O.O. 1Akinremi Babasola Ajiboye and Donald N. Flaten 1Department of Soil Science, University of Manitoba, Winnipeg, R3T 2NT, Canada We carried out this study in order to determine the forms of phosphorus in various organic amendments using state-of-the art spectroscopic technique. Anaerobically digested biosolids (BIO), hog (HOG), dairy (DAIRY), beef (BEEF) and poultry (POULTRY) manures were subjected to sequential extraction. The extracts were analyzed by solution 31P nuclear magnetic resonance (NMR) spectroscopy. Most of the total P analysed by inductively coupled plasma-optical emission spectroscopy (ICP-OES) in the sequential extracts of organic amendments were orthophosphate, except POULTRY, which was dominated by organic P. The labile P fraction in all the organic amendments, excluding POULTRY, was mainly orthophosphate P from readily soluble calcium and some aluminum phosphates. In the poultry litter, however, Ca phytate was the main P species controlling P solubility. Such knowledge of the differences in the chemical forms of phosphorus in organic amendments are essential for proper management of these amendments for agro-environmental purposes Key words: organic amendments, solution NMR, sequential fractionation, labile phosphorus

Heavy metal accumulation in surface sediments at the port of Cagliari (Sardinia, western Mediterranean): Environmental assessment using sequential extractions and benthic foraminifera.

PubMed

Schintu, Marco; Marrucci, Alessandro; Marras, Barbara; Galgani, Francois; Buosi, Carla; Ibba, Angelo; Cherchi, Antonietta

2016-10-15

Superficial sediments were taken at the port of Cagliari (Sardinia, Italy), which includes the oil terminal of one of the largest oil refineries in the Mediterranean. Significant trace metal concentrations were found in the whole port area. Sequential extraction of metals from the different sediment fractions (BCR method) showed a higher risk of remobilisation for Cd, which is mostly bound to the exchangeable fraction. Foraminiferal density and richness of species were variable across the study area. The living assemblages were characterized by low diversity in samples collected close to the port areas. Ammonia tepida and bolivinids, which were positively correlated with concentrations of heavy metals and organic matter content, appeared to show tolerance to the environmental disturbance. The sampling sites characterized by the highest values of biotic indices were located far from the port areas and present an epiphytic and epifaunal biocoenosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Optimization of Fe2+ supplement in anaerobic digestion accounting for the Fe-bioavailability.

PubMed

Cai, Yafan; Zhao, Xiaoling; Zhao, Yubin; Wang, Hongliang; Yuan, Xufeng; Zhu, Wanbin; Cui, Zongjun; Wang, Xiaofen

2018-02-01

Fe is widely used as an additive in anaerobic digestion, but its bioavailability and the mechanism by which it enhances digestion are unclear. In this study, sequential extraction was used to measure Fe bioavailability, while biochemical parameters, kinetics model and Q-PCR (fluorescence quantitative PCR) were used to explore its mechanism of stimulation. The results showed that sequential extraction is a suitable method to assess the anaerobic system bioavailability of Fe, which is low and fluctuates to a limited extent (1.7 to -3.1wt%), indicating that it would be easy for Fe levels to be insufficient. Methane yield increased when the added Fe 2+ was 10-500mg/L. Appropriate amounts of Fe 2+ accelerated the decomposition of rice straw and facilitated methanogen metabolism, thereby improving reactor performance. The modified Gompertz model better fitted the results than the first-order kinetic model. Feasibility analysis showed that addition of Fe 2+ at ≤50mg/L was suitable. Copyright © 2017. Published by Elsevier Ltd.

Near real-time adverse drug reaction surveillance within population-based health networks: methodology considerations for data accrual.

PubMed

Avery, Taliser R; Kulldorff, Martin; Vilk, Yury; Li, Lingling; Cheetham, T Craig; Dublin, Sascha; Davis, Robert L; Liu, Liyan; Herrinton, Lisa; Brown, Jeffrey S

2013-05-01

This study describes practical considerations for implementation of near real-time medical product safety surveillance in a distributed health data network. We conducted pilot active safety surveillance comparing generic divalproex sodium to historical branded product at four health plans from April to October 2009. Outcomes reported are all-cause emergency room visits and fractures. One retrospective data extract was completed (January 2002-June 2008), followed by seven prospective monthly extracts (January 2008-November 2009). To evaluate delays in claims processing, we used three analytic approaches: near real-time sequential analysis, sequential analysis with 1.5 month delay, and nonsequential (using final retrospective data). Sequential analyses used the maximized sequential probability ratio test. Procedural and logistical barriers to active surveillance were documented. We identified 6586 new users of generic divalproex sodium and 43,960 new users of the branded product. Quality control methods identified 16 extract errors, which were corrected. Near real-time extracts captured 87.5% of emergency room visits and 50.0% of fractures, which improved to 98.3% and 68.7% respectively with 1.5 month delay. We did not identify signals for either outcome regardless of extract timeframe, and slight differences in the test statistic and relative risk estimates were found. Near real-time sequential safety surveillance is feasible, but several barriers warrant attention. Data quality review of each data extract was necessary. Although signal detection was not affected by delay in analysis, when using a historical control group differential accrual between exposure and outcomes may theoretically bias near real-time risk estimates towards the null, causing failure to detect a signal. Copyright © 2013 John Wiley & Sons, Ltd.

Improving enzymatic hydrolysis efficiency of wheat straw through sequential autohydrolysis and alkaline post-extraction.

PubMed

Wu, Xinxing; Huang, Chen; Zhai, Shengcheng; Liang, Chen; Huang, Caoxing; Lai, Chenhuan; Yong, Qiang

2018-03-01

In this work, a two-step pretreatment process of wheat straw was established by combining autohydrolysis pretreatment and alkaline post-extraction. The results showed that employing alkaline post-extraction to autohydrolyzed wheat straw could significantly improve its enzymatic hydrolysis efficiency from 36.0% to 83.7%. Alkaline post-extraction lead to the changes of the structure characteristics of autohydrolyzed wheat straw. Associations between enzymatic hydrolysis efficiency and structure characteristics were also studied. The results showed that the factors of structure characteristics such as delignification, xylan removal yield, crystallinity, accessibility and hydrophobicity are positively related to enzymatic hydrolysis efficiency within a certain range for alkaline post-extracted wheat straw. The results demonstrated that autohydrolysis coupled with alkaline post-extraction is an effective and promising method to gain fermentable sugars from biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modified sequential extraction for biochar and petroleum coke: Metal release potential and its environmental implications.

PubMed

von Gunten, Konstantin; Alam, Md Samrat; Hubmann, Magdalena; Ok, Yong Sik; Konhauser, Kurt O; Alessi, Daniel S

2017-07-01

A modified Community Bureau of Reference (CBR) sequential extraction method was tested to assess the composition of untreated pyrogenic carbon (biochar) and oil sands petroleum coke. Wood biochar samples were found to contain lower concentrations of metals, but had higher fractions of easily mobilized alkaline earth and transition metals. Sewage sludge biochar was determined to be less recalcitrant and had higher total metal concentrations, with most of the metals found in the more resilient extraction fractions (oxidizable, residual). Petroleum coke was the most stable material, with a similar metal distribution pattern as the sewage sludge biochar. The applied sequential extraction method represents a suitable technique to recover metals from these materials, and is a valuable tool in understanding the metal retaining and leaching capability of various biochar types and carbonaceous petroleum coke samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sequential segmental terminal lenticular side-cut dissection for safe and effective small-incision lenticule extraction in thin lenticules.

PubMed

Jacob, Soosan; Agarwal, Amar; Mazzotta, Cosimo; Agarwal, Athiya; Raj, John Michael

2017-04-01

Small-incision lenticule extraction may be associated with complications such as partial lenticular dissection, torn lenticule, lenticular adherence to cap, torn cap, and sub-cap epithelial ingrowth, some of which are more likely to occur during low-myopia corrections. We describe sequential segmental terminal lenticular side-cut dissection to facilitate minimally traumatic and smooth lenticular extraction. Anterior lamellar dissection is followed by central posterior lamellar dissection, leaving a thin peripheral rim and avoiding the lenticular side cut. This is followed by sequential segmental dissection of the lenticular side cut in a manner that fixates the lenticule and provides sufficient resistance for smooth and complete dissection of the posterior lamellar cut without undesired movements of the lenticule. The technique is advantageous in thin lenticules, where the risk for complications is high, but can also be used in thick lenticular dissection using wider sweeps to separate the lenticular side cut sequentially. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Binding intensity and metal partitioning in soils affected by mining and smelting activities in Minas Gerais, Brazil.

PubMed

Lopes, G; Costa, E T S; Penido, E S; Sparks, D L; Guilherme, L R G

2015-09-01

Mining and smelting activities are potential sources of heavy metal contamination, which pose a threat to human health and ecological systems. This study investigated single and sequential extractions of Zn, Pb, and Cd in Brazilian soils affected by mining and smelting activities. Soils from a Zn mining area (soils A, B, C, D, E, and the control soil) and a tailing from a smelting area were collected in Minas Gerais state, Brazil. The samples were subjected to single (using Mehlich I solution) and sequential extractions. The risk assessment code (RAC), the redistribution index (U ts ), and the reduced partition index (I R ) have been applied to the sequential extraction data. Zinc and Cd, in soil samples from the mining area, were found mainly associated with carbonate forms. This same pattern did not occur for Pb. Moreover, the Fe-Mn oxides and residual fractions had important contributions for Zn and Pb in those soils. For the tailing, more than 70 % of Zn and Cd were released in the exchangeable fraction, showing a much higher mobility and availability of these metals at this site, which was also supported by results of RAC and I R . These differences in terms of mobility might be due to different chemical forms of the metals in the two sites, which are attributable to natural occurrence as well as ore processing.

Selenium speciation in seleniferous agricultural soils under different cropping systems using sequential extraction and X-ray absorption spectroscopy.

PubMed

Qin, Hai-Bo; Zhu, Jian-Ming; Lin, Zhi-Qing; Xu, Wen-Po; Tan, De-Can; Zheng, Li-Rong; Takahashi, Yoshio

2017-06-01

Selenium (Se) speciation in soil is critically important for understanding the solubility, mobility, bioavailability, and toxicity of Se in the environment. In this study, Se fractionation and chemical speciation in agricultural soils from seleniferous areas were investigated using the elaborate sequential extraction and X-ray absorption near-edge structure (XANES) spectroscopy. The speciation results quantified by XANES technique generally agreed with those obtained by sequential extraction, and the combination of both approaches can reliably characterize Se speciation in soils. Results showed that dominant organic Se (56-81% of the total Se) and lesser Se(IV) (19-44%) were observed in seleniferous agricultural soils. A significant decrease in the proportion of organic Se to the total Se was found in different types of soil, i.e., paddy soil (81%) > uncultivated soil (69-73%) > upland soil (56-63%), while that of Se(IV) presented an inverse tendency. This suggests that Se speciation in agricultural soils can be significantly influenced by different cropping systems. Organic Se in seleniferous agricultural soils was probably derived from plant litter, which provides a significant insight for phytoremediation in Se-laden ecosystems and biofortification in Se-deficient areas. Furthermore, elevated organic Se in soils could result in higher Se accumulation in crops and further potential chronic Se toxicity to local residents in seleniferous areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

Manganese speciation of laboratory-generated welding fumes

PubMed Central

Andrews, Ronnee N.; Keane, Michael; Hanley, Kevin W.; Feng, H. Amy; Ashley, Kevin

2015-01-01

The objective of this laboratory study was to identify and measure manganese (Mn) fractions in chamber-generated welding fumes (WF) and to evaluate and compare the results from a sequential extraction procedure for Mn fractions with that of an acid digestion procedure for measurement of total, elemental Mn. To prepare Mn-containing particulate matter from representative welding processes, a welding system was operated in short circuit gas metal arc welding (GMAW) mode using both stainless steel (SS) and mild carbon steel (MCS) and also with flux cored arc welding (FCAW) and shielded metal arc welding (SMAW) using MCS. Generated WF samples were collected onto polycarbonate filters before homogenization, weighing and storage in scintillation vials. The extraction procedure consisted of four sequential steps to measure various Mn fractions based upon selective solubility: (1) soluble Mn dissolved in 0.01 M ammonium acetate; (2) Mn (0,II) dissolved in 25 % (v/v) acetic acid; (3) Mn (III,IV) dissolved in 0.5% (w/v) hydroxylamine hydrochloride in 25% (v/v) acetic acid; and (4) insoluble Mn extracted with concentrated hydrochloric and nitric acids. After sample treatment, the four fractions were analyzed for Mn by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). WF from GMAW and FCAW showed similar distributions of Mn species, with the largest concentrations of Mn detected in the Mn (0,II) and insoluble Mn fractions. On the other hand, the majority of the Mn content of SMAW fume was detected as Mn (III,IV). Although the concentration of Mn measured from summation of the four sequential steps was statistically significantly different from that measured from the hot block dissolution method for total Mn, the difference is small enough to be of no practical importance for industrial hygiene air samples, and either method may be used for Mn measurement. The sequential extraction method provides valuable information about the oxidation state of Mn in samples and allows for comparison to results from previous work and from total Mn dissolution methods. PMID:26345630

Manganese speciation of laboratory-generated welding fumes.

PubMed

Andrews, Ronnee N; Keane, Michael; Hanley, Kevin W; Feng, H Amy; Ashley, Kevin

The objective of this laboratory study was to identify and measure manganese (Mn) fractions in chamber-generated welding fumes (WF) and to evaluate and compare the results from a sequential extraction procedure for Mn fractions with that of an acid digestion procedure for measurement of total, elemental Mn. To prepare Mn-containing particulate matter from representative welding processes, a welding system was operated in short circuit gas metal arc welding (GMAW) mode using both stainless steel (SS) and mild carbon steel (MCS) and also with flux cored arc welding (FCAW) and shielded metal arc welding (SMAW) using MCS. Generated WF samples were collected onto polycarbonate filters before homogenization, weighing and storage in scintillation vials. The extraction procedure consisted of four sequential steps to measure various Mn fractions based upon selective solubility: (1) soluble Mn dissolved in 0.01 M ammonium acetate; (2) Mn (0,II) dissolved in 25 % (v/v) acetic acid; (3) Mn (III,IV) dissolved in 0.5% (w/v) hydroxylamine hydrochloride in 25% (v/v) acetic acid; and (4) insoluble Mn extracted with concentrated hydrochloric and nitric acids. After sample treatment, the four fractions were analyzed for Mn by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). WF from GMAW and FCAW showed similar distributions of Mn species, with the largest concentrations of Mn detected in the Mn (0,II) and insoluble Mn fractions. On the other hand, the majority of the Mn content of SMAW fume was detected as Mn (III,IV). Although the concentration of Mn measured from summation of the four sequential steps was statistically significantly different from that measured from the hot block dissolution method for total Mn, the difference is small enough to be of no practical importance for industrial hygiene air samples, and either method may be used for Mn measurement. The sequential extraction method provides valuable information about the oxidation state of Mn in samples and allows for comparison to results from previous work and from total Mn dissolution methods.

Testing sequential extraction methods for the analysis of multiple stable isotope systems from a bone sample

NASA Astrophysics Data System (ADS)

Sahlstedt, Elina; Arppe, Laura

2017-04-01

Stable isotope composition of bones, analysed either from the mineral phase (hydroxyapatite) or from the organic phase (mainly collagen) carry important climatological and ecological information and are therefore widely used in paleontological and archaeological research. For the analysis of the stable isotope compositions, both of the phases, hydroxyapatite and collagen, have their more or less well established separation and analytical techniques. Recent development in IRMS and wet chemical extraction methods have facilitated the analysis of very small bone fractions (500 μg or less starting material) for PO43-O isotope composition. However, the uniqueness and (pre-) historical value of each archaeological and paleontological finding lead to preciously little material available for stable isotope analyses, encouraging further development of microanalytical methods for the use of stable isotope analyses. Here we present the first results in developing extraction methods for combining collagen C- and N-isotope analyses to PO43-O-isotope analyses from a single bone sample fraction. We tested sequential extraction starting with dilute acid demineralization and collection of both collagen and PO43-fractions, followed by further purification step by H2O2 (PO43-fraction). First results show that bone sample separates as small as 2 mg may be analysed for their δ15N, δ13C and δ18OPO4 values. The method may be incorporated in detailed investigation of sequentially developing skeletal material such as teeth, potentially allowing for the investigation of interannual variability in climatological/environmental signals or investigation of the early life history of an individual.

Evaluation of Pollutant Leaching Potential of Coal Ashes for Recycling

NASA Astrophysics Data System (ADS)

Park, D.; Woo, N. C.; Kim, H.; Yoon, H.; Chung, D.

2011-12-01

By 2009, coal ashes produced from coal-based power plants in Korea have been reused as cement supplement materials; however, the rest is mostly disposed in landfills inside the plant properties. Continuous production of coal ashes and limited landfill sites require more recycles of coal ashes as base materials, specifically in constructions of roads and of huge industrial complex. Previous researches showed that coal ashes could contain various metals such as arsenic(As), chromium(Cr), lead(Pb), nickel(Ni), selenium(Se), etc. In this study, we collected four types of bottom ashes and two of fly ashes from four coal-based power plants. These ash samples were tested with distilled water through the column leaching process in oxidized conditions. The column test results were compared with those of total digestion, sequential extraction processes and TCLP. Concentrations of metals in outflows from columns are generally greater in fly ashes than in bottom ashes, specifically for As, Se, B, Sr and SO4. Only one fly ash (J2-F) shows high concentrations of arsenic and selenium in leachate. Sequential extraction results indicate that these metals are in readily soluble forms, such as adsorbed, carbonated, and reducible forms. Results of TCLP analysis indicate no potential contaminants leached from the ashes. In conclusion, recycling of coal combustion ashes could be encouraged with proper tests such as sequential and leaching experiments.

Speciation and transformation of heavy metals during vermicomposting of animal manure.

PubMed

Lv, Baoyi; Xing, Meiyan; Yang, Jian

2016-06-01

This work was conducted to evaluate the effects of vermicomposting on the speciation and mobility of heavy metals (Zn, Pb, Cr, and Cu) in cattle dung (CD) and pig manure (PM) using tessier sequential extraction method. Results showed that the pH, total organic carbon and C/N ratio were reduced, while the electric conductivity and humic acid increased after 90days vermicomposting. Moreover, the addition of earthworm could accelerate organic stabilization in vermicomposting. The total heavy metals in final vermicompost from CD and PM were higher than the initial values and the control without worms. Sequential extraction indicated that vermicomposting decreased the migration and availability of heavy metals, and the earthworm could reduce the mobile fraction, while increase the stable fraction of heavy metals. Furthermore, these results indicated that vermicomposting played a positive role in stabilizing heavy metals in the treatment of animal manure. Copyright © 2016 Elsevier Ltd. All rights reserved.

Determination of element affinities by density fractionation of bulk coal samples

USGS Publications Warehouse

Querol, X.; Klika, Z.; Weiss, Z.; Finkelman, R.B.; Alastuey, A.; Juan, R.; Lopez-Soler, A.; Plana, F.; Kolker, A.; Chenery, S.R.N.

2001-01-01

A review has been made of the various methods of determining major and trace element affinities for different phases, both mineral and organic in coals, citing their various strengths and weaknesses. These include mathematical deconvolution of chemical analyses, direct microanalysis, sequential extraction procedures and density fractionation. A new methodology combining density fractionation with mathematical deconvolution of chemical analyses of whole coals and their density fractions has been evaluated. These coals formed part of the IEA-Coal Research project on the Modes of Occurrence of Trace Elements in Coal. Results were compared to a previously reported sequential extraction methodology and showed good agreement for most elements. For particular elements (Be, Mo, Cu, Se and REEs) in specific coals where disagreement was found, it was concluded that the occurrence of rare trace element bearing phases may account for the discrepancy, and modifications to the general procedure must be made to account for these.

Structural characterization of polysaccharides from bamboo

NASA Astrophysics Data System (ADS)

Kamil, Ruzaimah Nik Mohamad; Yusuf, Nur'aini Raman; Yunus, Normawati M.; Yusup, Suzana

2014-10-01

The alkaline and water soluble polysaccharides were isolate by sequential extractions with distilled water, 60% ethanol containing 1%, 5% and 8% NaOH. The samples were prepared at 60 °C for 3 h from local bamboo. The functional group of the sample were examined using FTIR analysis. The most precipitate obtained is from using 60% ethanol containing 8% NaOH with yield of 2.6%. The former 3 residues isolated by sequential extractions with distilled water, 60% ethanol containing 1% and 5% NaOH are barely visible after filtering with cellulose filter paper. The FTIR result showed that the water-soluble polysaccharides consisted mainly of OH group, CH group, CO indicates the carbohydrate and sugar chain. The sample weight loss was slightly decreased with increasing of temperature.

Comparison of three sequential extraction procedures for arsenic fractionation in highly polluted sites.

PubMed

Wan, Xiang; Dong, Haochen; Feng, Liu; Lin, Zhijia; Luo, Qiuchen

2017-07-01

Three sequential extraction procedures (SEPs) including Tessier, Rauret, and Shiowatana SEPs, were compared for arsenic fractionation using highly polluted soils. In the definition context of exchangeable, reducible, oxidizable and residual fractions, with similar arsenic recovery and reproducibility, Tessier and Rauret SEPs were comparable to each other, whereas Shiowatana SEP showed higher extraction efficiency in all the first three arsenic fractions, although it might overestimate the reducible arsenic. Pot experiment indicated three SEPs all could provide an estimation of the most bioavailable arsenic fraction, and the application of Shiowatana SEP should be preferred. Accordingly, a case study with Shiowatana SEP for a site near a realgar mine area is conducted. The results show that although arsenic in this area presents predominantly in the stable fractions, the sum of most bioavailable fractions was accounted around 11% of total arsenic, and moreover, about another 10% of the total arsenic, the fourth fraction in Shiowatana SEP is likely to be transferred into bioavailable species under suitable conditions, such as strong acid impact, revealing a real major risk source being formed. The study indicated that Shiowatana should be more suitable for arsenic fractionation to provide valuable information in the framework of risk assessment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Binding characteristics of Cu2+ to natural humic acid fractions sequentially extracted from the lake sediments.

PubMed

He, En; Lü, Changwei; He, Jiang; Zhao, Boyi; Wang, Jinghua; Zhang, Ruiqing; Ding, Tao

2016-11-01

Humic acids (HAs) determine the distribution, toxicity, bioavailability, and ultimate fate of heavy metals in the environment. In this work, ten HA fractions (F1-F10) were used as adsorbent, which were sequentially extracted from natural sediments of Lake Wuliangsuhai, to investigate the binding characteristics of Cu 2+ to HA. On the basis of the characterization results, differences were found between the ten extracted HA fractions responding to their elemental compositions and acidic functional groups. The characterization results reveal that the responses of ten extracted HA fractions to their elemental compositions and acidic functional groups were different. The O/C and (O + N)/C ratio of F1-F8 approximately ranged from 0.66 to 0.53 and from 0.72 to 0.61, respectively; the measured results showed that the contents of phenolic groups and carboxyl groups decreased from 4.46 to 2.60 mmol/g and 1.60 to 0.58 mmol/g, respectively. The binding characteristics of Cu 2+ to the ten HA fractions were well modeled by the bi-Langmuir model; the binding behavior of Cu 2+ to all the ten HA fractions were strongly impacted by pH and ionic strength. The FTIR and SEM-EDX image of HA fractions (pre- and post-adsorption) revealed that carboxyl and phenolic groups were responsible for the Cu 2+ sorption on the ten sequentially extracted HA fractions process, which is the same with the analysis of the ligand binding and bi-Langmuir models Accordingly, the adsorption capacity of the former HA fractions on Cu 2+ were higher than the latter ones, which may be attributed to the difference of carboxyl and phenolic group contents between the former and latter extracted HA fractions. Additionally, the functional groups with N and S should not be neglected. This work is hopeful to understand the environmental effect of humic substances, environmental geochemical behavior, and bioavailability of heavy metals in lakes.

Sorption of Cu(2+) on humic acids sequentially extracted from a sediment.

PubMed

Yang, Kun; Miao, Gangfen; Wu, Wenhao; Lin, Daohui; Pan, Bo; Wu, Fengchang; Xing, Baoshan

2015-11-01

In addition to the diverse properties of humic acids (HAs) extracted from different soils or sediments, chemical compositions, functional groups and structures of HAs extracted from a single soil or sediment could also be diverse and thus significantly affect sorption of heavy metals, which is a key process controlling the transfer, transformation and fate of heavy metals in the environment. In this study, we sequentially extracted four HA fractions from a single sediment and conducted the sorption experiments of Cu(2+) on these HA fractions. Our results showed that aromaticity and acidic group content of HA fraction decreased with increasing extraction. Earlier extracted HA fraction had higher sorption capacity and affinity for Cu(2+). There were two fractions of adsorbed Cu(2+) on HAs, i.e., ion exchanged fraction and surface bonded fraction, which can be captured mechanically by the bi-Langmuir model with good isotherm fitting. The ion exchanged fraction had larger sorption capacity but lower sorption affinity, compared with the surface bonded fraction. The dissociated carboxyl groups of HAs were responsible for both fractions of Cu(2+) sorption, due to the more Cu(2+) sorption on the earlier extracted HA fraction with more carboxyl groups and at higher pH. The intensive competition between H(+) and the exchangeable Cu(2+) could result in the decrease of ion exchanged capacity and affinity for Cu(2+) on HAs. Copyright © 2015 Elsevier Ltd. All rights reserved.

EXTRACTION OF SEDIMENT-BOUND CHLORINATED ORGANIC COMPOUNDS: IMPLICATIONS ON FATE AND HAZARD ASSESSMENT. (R825513C007)

EPA Science Inventory

Five methods were used for the extraction of hexachlorobutadiene and chlorobenzenes from a contaminated estuarine sediment. The following extraction methods were used: Soxhlet extraction, sonication and solvent extraction, sequential solvent extraction, saponification and solv...

Assessing of distribution, mobility and bioavailability of exogenous Pb in agricultural soils using isotopic labeling method coupled with BCR approach.

PubMed

Huang, Zhi-Yong; Xie, Hong; Cao, Ying-Lan; Cai, Chao; Zhang, Zhi

2014-02-15

The contamination of Pb in agricultural soils is one of the most important ecological problems, which potentially results in serious health risk on human health through food chain. Hence, the fate of exogenous Pb contaminated in agricultural soils is needed to be deeply explored. By spiking soils with the stable enriched isotopes of (206)Pb, the contamination of exogenous Pb(2+) ions in three agricultural soils sampled from the estuary areas of Jiulong River, China was simulated in the present study, and the distribution, mobility and bioavailability of exogenous Pb in the soils were investigated using the isotopic labeling method coupled with a four-stage BCR (European Community Bureau of Reference) sequential extraction procedure. Results showed that about 60-85% of exogenous Pb was found to distribute in reducible fractions, while the exogenous Pb in acid-extractable fractions was less than 1.0%. After planting, the amounts of exogenous Pb presenting in acid-extractable, reducible and oxidizable fractions in rhizospheric soils decreased by 60-66%, in which partial exogenous Pb was assimilated by plants while most of the metal might transfer downward due to daily watering and applying fertilizer. The results show that the isotopic labeling technique coupled with sequential extraction procedures enables us to explore the distribution, mobility and bioavailability of exogenous Pb contaminated in soils, which may be useful for the further soil remediation. Copyright © 2014 Elsevier B.V. All rights reserved.

Development of a rapid method for the sequential extraction and subsequent quantification of fatty acids and sugars from avocado mesocarp tissue.

PubMed

Meyer, Marjolaine D; Terry, Leon A

2008-08-27

Methods devised for oil extraction from avocado (Persea americana Mill.) mesocarp (e.g., Soxhlet) are usually lengthy and require operation at high temperature. Moreover, methods for extracting sugars from avocado tissue (e.g., 80% ethanol, v/v) do not allow for lipids to be easily measured from the same sample. This study describes a new simple method that enabled sequential extraction and subsequent quantification of both fatty acids and sugars from the same avocado mesocarp tissue sample. Freeze-dried mesocarp samples of avocado cv. Hass fruit of different ripening stages were extracted by homogenization with hexane and the oil extracts quantified for fatty acid composition by GC. The resulting filter residues were readily usable for sugar extraction with methanol (62.5%, v/v). For comparison, oil was also extracted using the standard Soxhlet technique and the resulting thimble residue extracted for sugars as before. An additional experiment was carried out whereby filter residues were also extracted using ethanol. Average oil yield using the Soxhlet technique was significantly (P < 0.05) higher than that obtained by homogenization with hexane, although the difference remained very slight, and fatty acid profiles of the oil extracts following both methods were very similar. Oil recovery improved with increasing ripeness of the fruit with minor differences observed in the fatty acid composition during postharvest ripening. After lipid removal, methanolic extraction was superior in recovering sucrose and perseitol as compared to 80% ethanol (v/v), whereas mannoheptulose recovery was not affected by solvent used. The method presented has the benefits of shorter extraction time, lower extraction temperature, and reduced amount of solvent and can be used for sequential extraction of fatty acids and sugars from the same sample.

Dynamic fractionation of trace metals in soil and sediment samples using rotating coiled column extraction and sequential injection microcolumn extraction: a comparative study.

PubMed

Rosende, Maria; Savonina, Elena Yu; Fedotov, Petr S; Miró, Manuel; Cerdà, Víctor; Wennrich, Rainer

2009-09-15

Dynamic fractionation has been recognized as an appealing alternative to conventional equilibrium-based sequential extraction procedures (SEPs) for partitioning of trace elements (TE) in environmental solid samples. This paper reports the first attempt for harmonization of flow-through dynamic fractionation using two novel methods, the so-called sequential injection microcolumn (SIMC) extraction and rotating coiled column (RCC) extraction. In SIMC extraction, a column packed with the solid sample is clustered in a sequential injection system, while in RCC, the particulate matter is retained under the action of centrifugal forces. In both methods, the leachants are continuously pumped through the solid substrates by the use of either peristaltic or syringe pumps. A five-step SEP was selected for partitioning of Cu, Pb and Zn in water soluble/exchangeable, acid-soluble, easily reducible, easily oxidizable and moderately reducible fractions from 0.2 to 0.5 g samples at an extractant flow rate of 1.0 mL min(-1) prior to leachate analysis by inductively coupled plasma-atomic emission spectrometry. Similarities and discrepancies between both dynamic approaches were ascertained by fractionation of TE in certified reference materials, namely, SRM 2711 Montana Soil and GBW 07311 sediment, and two real soil samples as well. Notwithstanding the different extraction conditions set by both methods, similar trends of metal distribution were in generally found. The most critical parameters for reliable assessment of mobilizable pools of TE in worse-case scenarios are the size-distribution of sample particles, the density of particles, the content of organic matter and the concentration of major elements. For reference materials and a soil rich in organic matter, the extraction in RCC results in slightly higher recoveries of environmentally relevant fractions of TE, whereas SIMC leaching is more effective for calcareous soils.

Sequential extraction of chromium, molybdenum, and vanadium in basic oxygen furnace slags.

PubMed

Spanka, Marina; Mansfeldt, Tim; Bialucha, Ruth

2018-06-02

Basic oxygen furnace slags (BOS) are by-products of basic oxygen steel production. Whereas the solubility of some elements from these slags has been well investigated, information about the mineralogy and related leaching, i.e., availability of the environmentally relevant elements chromium (Cr), molybdenum (Mo), and vanadium (V), is still lacking. The aim of this study was to investigate these issues with a modified, four-fraction-based, sequential extraction procedure (F1-F4), combined with X-ray diffraction, of two BOS. Extractants with increasing strength were used (F1 demineralized water, F2 CH 3 COOH + HCl, F3 Na 2 EDTA + NH 2 OH·HCl, and F4 HF + HNO 3 + H 2 O 2 ), and after each fraction, X-ray diffraction was performed. The recovery of Cr was moderate (66.5%) for one BOS, but significantly better (100.2%) for the other one. High recoveries were achieved for the other elements (Mo, 100.8-107.9% and V, 112.6-87.0%), indicating that the sequential extraction procedure was reliable when adapted to BOS. The results showed that Cr and Mo primarily occurred in F4, representing rather immobile elements under natural conditions, which were strongly bound into/onto Fe minerals (srebrodolskite, magnetite, hematite, or wustite). In contrast, V was more mobile with proportional higher findings in F2 and F3, and the X-ray diffraction results reveal that V was not solely bound into Ca minerals (larnite, hatrurite, kirschsteinite, and calcite), but also bound to Fe minerals. The results indicated that the total amount of recovery was a poor indicator of the availability of elements and did not correspond to the leaching of elements from BOS.

High-resolution extraction of particle size via Fourier Ptychography

NASA Astrophysics Data System (ADS)

Li, Shengfu; Zhao, Yu; Chen, Guanghua; Luo, Zhenxiong; Ye, Yan

2017-11-01

This paper proposes a method which can extract the particle size information with a resolution beyond λ/NA. This is achieved by applying Fourier Ptychographic (FP) ideas to the present problem. In a typical FP imaging platform, a 2D LED array is used as light sources for angle-varied illuminations, a series of low-resolution images was taken by a full sequential scan of the array of LEDs. Here, we demonstrate the particle size information is extracted by turning on each single LED on a circle. The simulated results show that the proposed method can reduce the total number of images, without loss of reliability in the results.

Attention-Based Recurrent Temporal Restricted Boltzmann Machine for Radar High Resolution Range Profile Sequence Recognition.

PubMed

Zhang, Yifan; Gao, Xunzhang; Peng, Xuan; Ye, Jiaqi; Li, Xiang

2018-05-16

The High Resolution Range Profile (HRRP) recognition has attracted great concern in the field of Radar Automatic Target Recognition (RATR). However, traditional HRRP recognition methods failed to model high dimensional sequential data efficiently and have a poor anti-noise ability. To deal with these problems, a novel stochastic neural network model named Attention-based Recurrent Temporal Restricted Boltzmann Machine (ARTRBM) is proposed in this paper. RTRBM is utilized to extract discriminative features and the attention mechanism is adopted to select major features. RTRBM is efficient to model high dimensional HRRP sequences because it can extract the information of temporal and spatial correlation between adjacent HRRPs. The attention mechanism is used in sequential data recognition tasks including machine translation and relation classification, which makes the model pay more attention to the major features of recognition. Therefore, the combination of RTRBM and the attention mechanism makes our model effective for extracting more internal related features and choose the important parts of the extracted features. Additionally, the model performs well with the noise corrupted HRRP data. Experimental results on the Moving and Stationary Target Acquisition and Recognition (MSTAR) dataset show that our proposed model outperforms other traditional methods, which indicates that ARTRBM extracts, selects, and utilizes the correlation information between adjacent HRRPs effectively and is suitable for high dimensional data or noise corrupted data.

Inhibition of norsolorinic acid accumulation to Aspergillus parasiticus by marine actinomycetes

NASA Astrophysics Data System (ADS)

Yan, Peisheng; Shi, Cuijuan; Shen, Jihong; Wang, Kai; Gao, Xiujun; Li, Ping

2014-11-01

Thirty-six strains of marine actinomycetes were isolated from a sample of marine sediment collected from the Yellow Sea and evaluated in terms of their inhibitory activity on the growth of Aspergillus parasiticus and the production of norsolorinic acid using dual culture plate assay and agar diffusion methods. Among them, three strains showed strong antifungal activity and were subsequently identified as Streptomyces sp. by 16S rRNA gene sequencing analysis. The supernatant from the fermentation of the MA01 strain was extracted sequentially with chloroform and ethyl acetate, and the activities of the extracts were determined by tip culture assay. The assay results show that both extracts inhibited mycelium growth and toxin production, and the inhibitory activities of the extracts increased as their concentrations increased. The results of this study suggest that marine actinomycetes are biologically important for the control of mycotoxins, and that these bacteria could be used as novel biopesticides against mycotoxins.

Enzymatic treatment to improve extraction of capsaicinoids and carotenoids from chili (Capsicum annuum) fruits.

PubMed

Salgado-Roman, Manuel; Botello-Alvarez, Enrique; Rico-Martínez, Ramiro; Jiménez-Islas, Hugo; Cárdenas-Manríquez, Marcela; Navarrete-Bolaños, José Luis

2008-11-12

Enzymatic treatments using noncommercial enzymes as a means to the improve the extraction of carotenoids and capsaicinoids from chili fruits are explored in this study. The results show that it is possible to obtain chili fruit powder with a higher concentration of both capsaicinoids and carotenoids than previously reported for similar processes. Furthermore, extraction yields above 96% for carotenoids and 85% for capsaicinoids as separate fractions can be achieved using a sequential and selective two-stage extraction. Evidence is presented demonstrating that the content and extraction yield depend directly on the extent of the enzymatic hydrolysis of chili cell walls, and higher yields are obtained when the sample is completely hydrolyzed. The enzymatic treatment described here is a promising alternative to current industrial practices, and it improves the extraction of carotenoids and capsaicinoids from chili fruits.

[Relation between distribution of phosphorus form in the sediment of typical urban shallow lakes and eutrophication].

PubMed

Wang, Chao; Zou, Li-Min; Wang, Pei-Fang; Lin, Zhi-Ping

2008-05-01

The forms of phosphorus in the surface sediments were extracted and determined sequentially with ethylene dinitrilo tetracetic acid (EDTA) technique in three urban shallow lakes: Lake Xuanwu, Lake Mochou and Lake Daming. The results showed that the iron and calcium-bound phosphate, about accounting for 80%, were the main forms of total phosphorus. The contents of iron bound phosphate in Lake Xuanwu and Lake Mochou were higher than that of Lake Daming, reaching 30%-40%. The organic phosphorus existed mainly in the form of alkali extractable phosphorus, while the contents of acid extractable organic phosphorus were low. However, the proportion of acid extractable organic phosphorus to the total phosphorus can indicate the degree of lake eutrophication.

Semiautomatic sequential extraction of polycyclic aromatic hydrocarbons and elemental bio-accessible fraction by accelerated solvent extraction on a single particulate matter sample.

PubMed

Astolfi, Maria Luisa; Di Filippo, Patrizia; Gentili, Alessandra; Canepari, Silvia

2017-11-01

We describe the optimization and validation of a sequential extractive method for the determination of the polycyclic aromatic hydrocarbons (PAHs) and elements (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, V and Zn) that are chemically fractionated into bio-accessible and mineralized residual fractions on a single particulate matter filter. The extraction is performed by automatic accelerated solvent extraction (ASE); samples are sequentially treated with dichloromethane/acetone (4:1) for PAHs extraction and acetate buffer (0.01M; pH 4.5) for elements extraction (bio-accessible fraction). The remaining solid sample is then collected and subjected to acid digestion with HNO 3 :H 2 O 2 (2:1) to determine the mineralized residual element fraction. We also describe a homemade ASE cell that reduces the blank values for most elements; in this cell, the steel frit was replaced by a Teflon pierced disk and a Teflon cylinder was used as the filler. The performance of the proposed method was evaluated in terms of recovery from standard reference material (SRM 1648 and SRM 1649a) and repeatability. The equivalence between the new ASE method and conventional methods was verified for PAHs and for bio-accessible and mineralized residual fractions of elements on PM 10 twin filters. Copyright © 2017 Elsevier B.V. All rights reserved.

Learning Orthographic Structure With Sequential Generative Neural Networks.

PubMed

Testolin, Alberto; Stoianov, Ivilin; Sperduti, Alessandro; Zorzi, Marco

2016-04-01

Learning the structure of event sequences is a ubiquitous problem in cognition and particularly in language. One possible solution is to learn a probabilistic generative model of sequences that allows making predictions about upcoming events. Though appealing from a neurobiological standpoint, this approach is typically not pursued in connectionist modeling. Here, we investigated a sequential version of the restricted Boltzmann machine (RBM), a stochastic recurrent neural network that extracts high-order structure from sensory data through unsupervised generative learning and can encode contextual information in the form of internal, distributed representations. We assessed whether this type of network can extract the orthographic structure of English monosyllables by learning a generative model of the letter sequences forming a word training corpus. We show that the network learned an accurate probabilistic model of English graphotactics, which can be used to make predictions about the letter following a given context as well as to autonomously generate high-quality pseudowords. The model was compared to an extended version of simple recurrent networks, augmented with a stochastic process that allows autonomous generation of sequences, and to non-connectionist probabilistic models (n-grams and hidden Markov models). We conclude that sequential RBMs and stochastic simple recurrent networks are promising candidates for modeling cognition in the temporal domain. Copyright © 2015 Cognitive Science Society, Inc.

Assessing Metal Mobilization from Industrially Lead ...

EPA Pesticide Factsheets

A series of leaching and partitioning tests (Toxicity Characteristic Leaching Procedure (TCLP), Synthetic Precipitation Leaching Procedure (SPLP), Controlled Acidity Leaching Protocol (CALP), Acid Neutralization Capacity (ANC), and sequential extraction) were applied to three different soils to study potential mobility of metals into groundwater. Two of these soils were lead (Pb)-contaminated soils (Hotspot 1 and Hotspot 2) collected from an urban site associated with lead smelting and other industrial operations. The third sample (Stockpile) was soil affected by previous contamination in the area, removed from residential properties, stockpiled, and selected to be used as fill material in the studied site. The TCLP and CALP showed that Pb could be released from both hotspots, but were not released in the acidic rainfall extraction fluid of the SPLP. The sequential extraction showed that Pb in the hotspot soils was associated with the carbonate fraction, while As was associated with the Fe and Mn oxides. The stockpile released traces of Pb or As in the TCLP and CALP, but the ANC only released Pb under acidic conditions and the SPLP did not release Pb or As. Overall, the projected repository with Stockpile would not pose imminent danger to groundwater because, under the expected environmental conditions, Pb and As tend to remain in the solid phase. The objectives of this study were to determine if the stockpiled soil was suitable for the intended fill purpo

Sequential Extractions and Toxicity Potential of Trace Metals Absorbed into Airborne Particles in an Urban Atmosphere of Southwestern Nigeria

PubMed Central

Ediagbonya, Thompson Faraday

2018-01-01

The paper investigates the hypothesis that biotoxicities of trace metals depend not only on the concentration as expressed by the total amount, but also on their geochemical fractions and bioavailability. Airborne particles were collected using SKC Air Check XR 5000 high volume Sampler at a human breathing height of 1.5–2.0 meters, during the dry season months from November 2014 to March 2015 at different locations in Akure (7°10′N and 5°15′E). The geochemical-based sequential extractions were performed on the particles using a series of increasingly stringent solutions selected to extract metals (Cd, Cu, Cr, Ni, Pb, Zn, and Mn) into four operational geochemical phases—exchangeable, reducible, organic, and residual—and then quantified using an Atomic Absorption Spectrophotometer. The results showed metals concentration of order Pb > Cr > Cd > Zn > Ni > Cu > Mn. However, most metals in the samples exist in nonmobile fractions: exchangeable (6.43–16.2%), reducible (32.58–47.39%), organic (4.73–9.88%), and residual (18.28–27.53%). The pollution indices show ingestion as the leading route of metal exposure, with noncarcinogenic (HQ) and cancer risk (HI) for humans in the area being higher than 1.0 × 10−4, indicating a health threat. PMID:29686588

Thermal, emulsifying and rheological properties of polysaccharides sequentially extracted from Vaccinium bracteatum Thunb leaves.

PubMed

Xu, Qi-Xin; Shi, Jun-Jun; Zhang, Jian-Guo; Li, Ling; Jiang, Li; Wei, Zhao-Jun

2016-12-01

Plant polysaccharides are widely used in food industry as thickening and gelling agents and these attributes largely depend on their thermal, emulsifying and rheological properties. As known, the extraction methods always bring about the diversification of property and functions of polysaccharides. Thus, the Vaccinium bracteatum Thunb leaves polysaccharides (VBTLP) were sequentially extracted using hot buffer (HBSS), chelating agent (CHSS), dilute alkaline (DASS) and concentrated alkaline (CASS). The thermal, emulsifying and rheological properties of VBTLP were investigated in the present study. Within the range of 20-225°C, CHSS showed the highest peak temperature, whereas HBSS displayed the highest endothermic enthalpy and highest emulsifying activity, while, CASS showed the longest emulsifying stability. The VBTLP solutions exhibited non-Newtonian shear-thinning behavior within the concentrations of 0.6-2.5%. The apparent viscosity of VBTLP solution decreased under following conditions: acidic pH (4.0), alkaline pH (10.0), in the presence of Ca 2+ and at high temperature, while it increased in the presence of Na + and at freezing conditions. The modulus G' and G″ of VBTLP solutions were increased with increasing oscillation frequency, and the crossover frequency shifted to lower values when the polysaccharide content increased. The above results of thermal, emulsifying and rheological properties of VBTLPs supplied the basis for V. bracteatum leaves in potential industrial applications of foods. Copyright © 2016 Elsevier B.V. All rights reserved.

Multi-constituent synergism is responsible for anti-inflammatory effect of Azadirachta indica leaf extract.

PubMed

Umar, Muhammad Ihtisham; Asmawi, Mohd Zaini; Sadikun, Amirin; Abdul Majid, A M S; Atangwho, Item Justin; Khadeer Ahamed, Mohamed B; Altaf, Rabia; Ahmad, Ashfaq

2014-11-01

Azadirachta indica A. Juss. (Meliaceaes) leaves have been used traditionally to treat swelling and rheumatism in Indian cultures. To fractionate A. indica leaf extracts using bioactivity guided manner for identification of the active anti-inflammatory principles. Polarity-gradient sequential extracts (petroleum ether, chloroform, methanol, and water) of A. indica leaves were screened for their anti-inflammatory potential using the carrageenan-induced rat paw edema model (1 g/kg). The chloroform extract was sequentially fractionated to obtain n-hexane (F-1), n-hexane-chloroform (F-2), and chloroform (F-3) fractions and their inhibitory effect on rat paw edema was evaluated (500 mg/kg). Inhibitory effect of F-2 on granuloma formation, plasma interleukin (IL-1), and tumor necrosis factor (TNF-α) was assessed at the doses of 100, 200, and 400 mg/kg using the cotton pellet assay in rats. Three sub-fractions (SF-1, SF-2, and SF-3) were obtained upon chromatography of F-2, and their inhibitory effect on cyclooxygenase was assessed at 200 µg/mL concentration. The sub-fractions were subjected to gas chromatography-mass spectrometry (GC-MS). All the extracts showed significant anti-inflammatory effect; however, chloroform extract was the most effective against paw edema (53.25% inhibition). The three fractions of chloroform extract showed significant effect, while F-2 being the most potent (51.02%). F-2 demonstrated dose-dependent inhibition of granuloma and cytokines. Interestingly, all the sub-fractions of F-2 inhibited COX-1 and COX-2 with almost equal potential. GC-MS revealed that chemically the sub-fractions were totally different from each other. Anti-inflammatory effect of A. indica is a result of cumulative and synergistic effects of diversified constituents with varying polarities that collectively exert the effect via suppression of cyclo-oxygenases and cytokines (IL-1 and TNF-α).

Chromium fate in constructed wetlands treating tannery wastewaters.

PubMed

Dotro, Gabriela; Palazolo, Paul; Larsen, Daniel

2009-06-01

Nine experimental wetlands were built to determine chromium partitioning inside systems treating tannery wastewaters. Results showed 5-day biochemical oxygen demand and chromium removals of 95 to 99% and 90 to 99%, respectively. The majority of chromium was found in association with media (96 to 98%), followed by effluents (2.9 to 3.9%), and the least was found in plant parts (0.1%). Chemical speciation modeling of solutions and scanning electron microscope analysis suggest two potential chromium removal mechanisms--sorption/coprecipitation with iron hydroxides or oxyhydroxides and biomass sorption. The release of the majority of chromium in the iron- and organic-bound phases during sequential extractions supports the proposed dominant removal mechanisms. The use of a mixture of peat and gravel resulted in lower removal efficiencies and stronger partitioning in organic phases during sequential extractions. Chromium was efficiently removed by wetlands, retained through chemical and biological processes. Future research will focus on further exploring removal mechanisms and proposing management strategies for the chromium-containing wetland media.

Sequential low and medium frequency ultrasound assists biodegradation of wheat chaff by white rot fungal enzymes.

PubMed

Oliver, Christine M; Mawson, Raymond; Melton, Laurence D; Dumsday, Geoff; Welch, Jessica; Sanguansri, Peerasak; Singh, Tanoj K; Augustin, Mary Ann

2014-10-13

The consequences of ultrasonic pre-treatment using low (40 kHz) and medium (270 kHz) frequency (40 kHz followed by 270 kHz) on the degradation of wheat chaff (8 g 100ml(-1) acetate buffer, pH 5) were evaluated. In addition, the effects of the ultrasonic pre-treatment on the degradation of the wheat chaff when subsequently exposed to enzyme extracts from two white rot fungi (Phanerochaete chrysosporium and Trametes sp.) were investigated. Pre-treatment by sequential low and medium frequency ultrasound had a disruptive effect on the lignocellulosic matrix. Analysis of the phenolic-derived volatiles after enzymatic hydrolysis showed that biodegradation with the enzyme extract obtained from P. chrysosporium was more pronounced compared to that of the Trametes sp. The efficacy of the ultrasonic pre-treatment was attributed to increased enzyme accessibility of the cellulose fibrils due to sonication-induced disruption of the plant surface structure, as shown by changes in the microstructure. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preliminary results of sequential extraction experiments for selenium on mine waste and stream sediments from Vermont, Maine, and New Zealand

USGS Publications Warehouse

Piatak, N.M.; Seal, R.R.; Sanzolone, R.F.; Lamothe, P.J.; Brown, Z.A.

2006-01-01

We report the preliminary results of sequential partial dissolutions used to characterize the geochemical distribution of selenium in stream sediments, mine wastes, and flotation-mill tailings. In general, extraction schemes are designed to extract metals associated with operationally defined solid phases. Total Se concentrations and the mineralogy of the samples are also presented. Samples were obtained from the Elizabeth, Ely, and Pike Hill mines in Vermont, the Callahan mine in Maine, and the Martha mine in New Zealand. These data are presented here with minimal interpretation or discussion. Further analysis of the data will be presented elsewhere.

Evaluation of the mobility and pollution index of selected essential/toxic metals in paddy soil by sequential extraction method.

PubMed

Hasan, Maria; Kausar, Dilshad; Akhter, Gulraiz; Shah, Munir H

2018-01-01

Comparative distribution and mobility of selected essential and toxic metals in the paddy soil from district Sargodha, Pakistan was evaluated by the modified Community Bureau of Reference (mBCR) sequential extraction procedure. Most of the soil samples showed slightly alkaline nature while the soil texture was predominantly silty loam in nature. The metal contents were quantified in the exchangeable, reducible, oxidisable and residual fractions of the soil by flame atomic absorption spectrophotometry and the metal data were subjected to the statistical analyses in order to evaluate the mutual relationships among the metals in each fraction. Among the metals, Ca, Sr and Mn were found to be more mobile in the soil. A number of significant correlations between different metal pairs were noted in various fractions. Contamination factor, geoaccumulation index and enrichment factor revealed extremely severe enrichment/contamination for Cd; moderate to significant enrichment/contamination for Ni, Zn, Co and Pb while Cr, Sr, Cu and Mn revealed minimal to moderate contamination and accumulation in the soil. Multivariate cluster analysis showed significant anthropogenic intrusions of the metals in various fractions. Copyright © 2017 Elsevier Inc. All rights reserved.

Prediction of anaerobic biodegradability and bioaccessibility of municipal sludge by coupling sequential extractions with fluorescence spectroscopy: towards ADM1 variables characterization.

PubMed

Jimenez, Julie; Gonidec, Estelle; Cacho Rivero, Jesús Andrés; Latrille, Eric; Vedrenne, Fabien; Steyer, Jean-Philippe

2014-03-01

Advanced dynamic anaerobic digestion models, such as ADM1, require both detailed organic matter characterisation and intimate knowledge of the involved metabolic pathways. In the current study, a methodology for municipal sludge characterization is investigated to describe two key parameters: biodegradability and bioaccessibility of organic matter. The methodology is based on coupling sequential chemical extractions with 3D fluorescence spectroscopy. The use of increasingly strong solvents reveals different levels of organic matter accessibility and the spectroscopy measurement leads to a detailed characterisation of the organic matter. The results obtained from testing 52 municipal sludge samples (primary, secondary, digested and thermally treated) showed a successful correlation with sludge biodegradability and bioaccessibility. The two parameters, traditionally obtained through the biochemical methane potential (BMP) lab tests, are now obtain in only 5 days compared to the 30-60 days usually required. Experimental data, obtained from two different laboratory scale reactors, were used to validate the ADM1 model. The proposed approach showed a strong application potential for reactor design and advanced control of anaerobic digestion processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

A new perspective of using sequential extraction: To predict the deficiency of trace elements during anaerobic digestion.

PubMed

Cai, Yafan; Wang, Jungang; Zhao, Yubin; Zhao, Xiaoling; Zheng, Zehui; Wen, Boting; Cui, Zongjun; Wang, Xiaofen

2018-09-01

Trace elements were commonly used as additives to facilitate anaerobic digestion. However, their addition is often blind because of the complexity of reaction conditions, which has impeded their widespread application. Therefore, this study was conducted to evaluate deficiencies in trace elements during anaerobic digestion by establishing relationships between changes in trace element bioavailability (the degree to which elements are available for interaction with biological systems) and digestion performance. To accomplish this, two batch experiments were conducted. In the first, sequential extraction was used to detect changes in trace element fractions and then to evaluate trace element bioavailability in the whole digestion cycle. In the second batch experiment, trace elements (Co, Fe, Cu, Zn, Mn, Mo and Se) were added to the reaction system at three concentrations (low, medium and high) and their effects were monitored. The results showed that sequential extraction was a suitable method for assessment of the bioavailability of trace elements (appropriate coefficient of variation and recovery rate). The results revealed that Se had the highest (44.2%-70.9%) bioavailability, while Fe had the lowest (1.7%-3.0%). A lack of trace elements was not directly related to their absolute bioavailability, but was instead associated with changes in their bioavailability throughout the digestion cycle. Trace elements were insufficient when their bioavailability was steady or increased over the digestion cycle. These results indicate that changes in trace element bioavailability during the digestion cycle can be used to predict their deficiency. Copyright © 2018 Elsevier Ltd. All rights reserved.

SW-846 Test Method 3200: Mercury Species Fractionation and Quantification by Microwave Assisted Extraction, Selective Solvent Extraction and/or Solid Phase Extraction

EPA Pesticide Factsheets

a sequential extraction and separation procedure that maybe used in conjunction with a determinative method to differentiate mercury species that arepresent in soils and sediments. provides information on both total mercury andvarious mercury species.

Methodological Considerations for Hair Cortisol Measurements in Children

PubMed Central

Slominski, Radomir; Rovnaghi, Cynthia R.; Anand, Kanwaljeet J. S.

2015-01-01

Background Hair cortisol levels are used increasingly as a measure for chronic stress in young children. We propose modifications to the current methods used for hair cortisol analysis to more accurately determine reference ranges for hair cortisol across different populations and age groups. Methods The authors compared standard (finely cutting hair) vs. milled methods for hair processing (n=16), developed a 4-step extraction process for hair protein and cortisol (n=16), and compared liquid chromatography-mass spectrometry (LCMS) vs. ELISA assays for measuring hair cortisol (n=28). The extraction process included sequential incubations in methanol and acetone, repeated twice. Hair protein was measured via spectrophotometric ratios at 260/280 nm to indicate the hair dissolution state using a BioTek® plate reader and dedicated software. Hair cortisol was measured using an ELISA assay kit. Individual (n=13), pooled hair samples (n=12) with high, intermediate, and low cortisol values and the ELISA assay internal standards (n=3) were also evaluated by LCMS. Results Milled and standard methods showed highly correlated hair cortisol (rs=0.951, p<0.0001) and protein values (rs=0.902, p=0.0002), although higher yields of cortisol and protein were obtained from the standard method in 13/16 and 14/16 samples respectively (p<0.05). Four sequential extractions yielded additional amounts of protein (36.5%, 27.5%, 30.5%, 3.1%) and cortisol (45.4%, 31.1%, 15.1%, 0.04%) from hair samples. Cortisol values measured by LCMS and ELISA were correlated (rs=0.737; p<0.0001), although cortisol levels (median [IQR]) detected in the same samples by LCMS (38.7 [14.4, 136] ng/ml) were lower than by ELISA (172.2 [67.9, 1051] ng/ml). LCMS also detected cortisone, which comprised 13.4% (3.7%, 25.9%) of the steroids detected. Conclusion Methodological studies suggest that finely cutting hair with sequential incubations in methanol and acetone, repeated twice, extracts greater yields of cortisol than does milled hair. Based on these findings, at least three incubations may be required to extract most of the cortisol in human hair samples. In addition, ELISA-based assays showed greater sensitivity for measuring hair cortisol levels than LCMS-based assays. PMID:25811341

Potential contaminants at a dredged spoil placement site, Charles City County, Virginia, as revealed by sequential extraction

PubMed Central

Tang, Jianwu; Whittecar, G Richard; Johannesson, Karen H; Daniels, W Lee

2004-01-01

Backfills of dredged sediments onto a former sand and gravel mine site in Charles City County, VA may have the potential to contaminate local groundwater. To evaluate the mobility of trace elements and to identify the potential contaminants from the dredged sediments, a sequential extraction scheme was used to partition trace elements associated with the sediments from the local aquifer and the dredged sediments into five fractions: exchangeable, acidic, reducible, oxidizable, and residual phases. Sequential extractions indicate that, for most of the trace elements examined, the residual phases account for the largest proportion of the total concentrations, and their total extractable fractions are mainly from reducible and oxidizable phases. Only Cd, Pb, and Zn have an appreciable extractable proportion from the acidic phase in the filled dredged sediments. Our groundwater monitoring data suggest that the dredged sediments are mainly subject to a decrease in pH and a series of oxidation reactions, when exposed to the atmosphere. Because the trace elements released by carbonate dissolution and the oxidation (e.g., organic matter degradation, iron sulfide and, ammonia oxidation) are subsequently immobilized by sorption to iron, manganese, and aluminum oxides, no potential contaminants to local groundwater are expected by addition of the dredged sediments to this site.

Sequential extraction of flavonoids and pectin from yellow passion fruit rind using pressurized solvent or ultrasound.

PubMed

de Souza, Caroline G; Rodrigues, Tigressa Hs; E Silva, Lorena Ma; Ribeiro, Paulo Rv; de Brito, Edy S

2018-03-01

Passion fruit rind (PFR) represents 90% of the total fruit weight and is wasted during juice processing. Passion fruit rind is known to contain flavonoids and pectin. An alternative use for this fruit juice industrial residue is to obtain these compounds. This study aimed to verify the influence of pressurized solvent extraction (PSE) or ultrasound assisted extraction (UAE) of flavonoid and pectin in a sequential process. The PSE using ethanol at 60:40 (v/v) yielded a total polyphenol content of 4.67 g GAE kg -1 PFR, orientin-7-O-glucoside (1.57 g kg -1 PFR) and luteolin-6-C-glucoside (2.44 g kg -1 PFR). Pectin yield was 165 g kg -1 PFR, either in PSE or UAE. Pectin characterization indicates that the pectic structure has basically homogalacturonans and galacturonate followed by a galacturonic acid ester unit, with methylation degree of 70%. With this study it can be concluded that mixtures of alcohols with water favor the extraction of bioactive compounds of passion fruit peel. Both PSE and UAE were effective in sequentially extracting flavonoids and pectin. The preferred solvent is ethanol due to its lower toxicity. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Speckle pattern sequential extraction metric for estimating the focus spot size on a remote diffuse target.

PubMed

Yu, Zhan; Li, Yuanyang; Liu, Lisheng; Guo, Jin; Wang, Tingfeng; Yang, Guoqing

2017-11-10

The speckle pattern (line by line) sequential extraction (SPSE) metric is proposed by the one-dimensional speckle intensity level crossing theory. Through the sequential extraction of received speckle information, the speckle metrics for estimating the variation of focusing spot size on a remote diffuse target are obtained. Based on the simulation, we will give some discussions about the SPSE metric range of application under the theoretical conditions, and the aperture size will affect the metric performance of the observation system. The results of the analyses are verified by the experiment. This method is applied to the detection of relative static target (speckled jitter frequency is less than the CCD sampling frequency). The SPSE metric can determine the variation of the focusing spot size over a long distance, moreover, the metric will estimate the spot size under some conditions. Therefore, the monitoring and the feedback of far-field spot will be implemented laser focusing system applications and help the system to optimize the focusing performance.

Automatic extraction of building boundaries using aerial LiDAR data

NASA Astrophysics Data System (ADS)

Wang, Ruisheng; Hu, Yong; Wu, Huayi; Wang, Jian

2016-01-01

Building extraction is one of the main research topics of the photogrammetry community. This paper presents automatic algorithms for building boundary extractions from aerial LiDAR data. First, segmenting height information generated from LiDAR data, the outer boundaries of aboveground objects are expressed as closed chains of oriented edge pixels. Then, building boundaries are distinguished from nonbuilding ones by evaluating their shapes. The candidate building boundaries are reconstructed as rectangles or regular polygons by applying new algorithms, following the hypothesis verification paradigm. These algorithms include constrained searching in Hough space, enhanced Hough transformation, and the sequential linking technique. The experimental results show that the proposed algorithms successfully extract building boundaries at rates of 97%, 85%, and 92% for three LiDAR datasets with varying scene complexities.

A sequential analysis of classroom discourse in Italian primary schools: the many faces of the IRF pattern.

PubMed

Molinari, Luisa; Mameli, Consuelo; Gnisci, Augusto

2013-09-01

A sequential analysis of classroom discourse is needed to investigate the conditions under which the triadic initiation-response-feedback (IRF) pattern may host different teaching orientations. The purpose of the study is twofold: first, to describe the characteristics of classroom discourse and, second, to identify and explore the different interactive sequences that can be captured with a sequential statistical analysis. Twelve whole-class activities were video recorded in three Italian primary schools. We observed classroom interaction as it occurs naturally on an everyday basis. In total, we collected 587 min of video recordings. Subsequently, 828 triadic IRF patterns were extracted from this material and analysed with the programme Generalized Sequential Query (GSEQ). The results indicate that classroom discourse may unfold in different ways. In particular, we identified and described four types of sequences. Dialogic sequences were triggered by authentic questions, and continued through further relaunches. Monologic sequences were directed to fulfil the teachers' pre-determined didactic purposes. Co-constructive sequences fostered deduction, reasoning, and thinking. Scaffolding sequences helped and sustained children with difficulties. The application of sequential analyses allowed us to show that interactive sequences may account for a variety of meanings, thus making a significant contribution to the literature and research practice in classroom discourse. © 2012 The British Psychological Society.

Pumpkin (Cucurbita maxima) seed proteins: sequential extraction processing and fraction characterization.

PubMed

Rezig, Leila; Chibani, Farhat; Chouaibi, Moncef; Dalgalarrondo, Michèle; Hessini, Kamel; Guéguen, Jacques; Hamdi, Salem

2013-08-14

Seed proteins extracted from Tunisian pumpkin seeds ( Cucurbita maxima ) were investigated for their solubility properties and sequentially extracted according to the Osborne procedure. The solubility of pumpkin proteins from seed flour was greatly influenced by pH changes and ionic strength, with higher values in the alkaline pH regions. It also depends on the seed defatting solvent. Protein solubility was decreased by using chloroform/methanol (CM) for lipid extraction instead of pentane (P). On the basis of differential solubility fractionation and depending on the defatting method, the alkali extract (AE) was the major fraction (42.1 (P), 22.3% (CM)) compared to the salt extract (8.6 (P), 7.5% (CM)). In salt, alkali, and isopropanol extracts, all essential amino acids with the exceptions of threonine and lysine met the minimum requirements for preschool children (FAO/WHO/UNU). The denaturation temperatures were 96.6 and 93.4 °C for salt and alkali extracts, respectively. Pumpkin protein extracts with unique protein profiles and higher denaturation temperatures could impart novel characteristics when used as food ingredients.

THE LIBERATION OF ARSENOSUGARS FROM MATRIX COMPONENTS IN DIFFICULT TO EXTRACT SEAFOOD SAMPLES UTILIZING TMAOH/ACETIC ACID SEQUENTIALLY IN A TWO-STAGE EXTRACTION PROCESS

EPA Science Inventory

Sample extraction is one of the most important steps in arsenic speciation analysis of solid dietary samples. One of the problem areas in this analysis is the partial extraction of arsenicals from seafood samples. The partial extraction allows the toxicity of the extracted arse...

Evaluation of Phosphate Fertilizers for the Immobilization of Cd in Contaminated Soils

PubMed Central

Yan, Yin; Zhou, Yi Qun; Liang, Cheng Hua

2015-01-01

A laboratory investigation was conducted to evaluate the efficiency of four phosphate fertilizers, including diammonium phosphate (DAP), potassium phosphate monobasic (MPP), calcium superphosphateon (SSP), and calcium phosphate tribasic (TCP), in terms of the toxicity and bioavailability of Cd in contaminated soils. The efficiency of immobilization was evaluated on the basis of two criteria: (a) the reduction of extractable Cd concentration below the TCLP regulatory level and (b) the Cd changes associated with specific operational soil fractions on the basis of sequential extraction data. Results showed that after 50 d immobilization, the extractable concentrations of Cd in DAP, MPP, SSP, and TCP treated soils decreased from 42.64 mg/kg (in the control) to 23.86, 21.86, 33.89, and 35.59 mg/kg, respectively, with immobilization efficiency in the order of MPP > DAP > SSP > TCP. Results from the assessment of Cd speciation via the sequential extraction procedure revealed that the soluble exchangeable fraction of Cd in soils treated with phosphate fertilizers, especially TCP, was considerably reduced. In addition, the reduction was correspondingly related to the increase in the more stable forms of Cd, that is, the metal bound to manganese oxides and the metal bound to crystalline iron oxides. Treatment efficiency increased as the phosphate dose (according to the molar ratio of PO4/Cd) increased. Immobilization was the most effective under the molar ratio of PO4/Cd at 4:1. PMID:25915051

Environmental Impacts Of Zirab Coal Washing Plant, Mazandaran, Iran

NASA Astrophysics Data System (ADS)

Moore, F.; Esmaeili, A.

2009-04-01

Extraction and beneficiation operations associated with coal mining increase the rate of chemical reaction of waste material to air and water media. Zirab coal washing plant is located on the bank of the Cherat stream in Mazandaran province, Iran. coal Mined from central Alborz coalfield mines is not suitable for use in Iranian Steel Corporation. Hence, coal ash content is reduced by physical and chemical processes in this plant. These processes leave a large quantity of liquid and solid wastes that accumulate in waste dump and tailing dam. sediment and water samples taken from Sheshrudbar and Cherat streams and also from Talar river show high concentration of Cd, Mo and As in water samples of coal washing plant and the associated drainage. Eh-pH diagrams revealed the chemical species of elements in water. The enrichment factor and geoaccumulation index show that Cd, Hg, Mo and V are enriched in bottom sediments of the coal washing plant and decrease with increasing distance from the plant. Sequential extraction analysis Results of three sediment samples of Cherat stream show that silicate bound is the major phase in samples taken before and after the plant, but adjacent to the plant, organic bound is dominant. The high concentration of Cd and Mo in the water soluble phase, is noticeable and may result in high mobility and bioavailability of these elements. Mann-Whitney and Wilcoxon tests on six samples, before and after the coal washing plant support the obtained results. Keywords: Zirab; coal washing plant; Sequential extraction analysis; Mann-whitney; Wilcoxon; Enrichment factor; Geoaccumulation index.

Learning Behavior Characterization with Multi-Feature, Hierarchical Activity Sequences

ERIC Educational Resources Information Center

Ye, Cheng; Segedy, James R.; Kinnebrew, John S.; Biswas, Gautam

2015-01-01

This paper discusses Multi-Feature Hierarchical Sequential Pattern Mining, MFH-SPAM, a novel algorithm that efficiently extracts patterns from students' learning activity sequences. This algorithm extends an existing sequential pattern mining algorithm by dynamically selecting the level of specificity for hierarchically-defined features…

Molecular Characteristics of Kraft-AQ Pulping Lignin Fractionated by Sequential Organic Solvent Extraction

PubMed Central

Wang, Kun; Xu, Feng; Sun, Runcang

2010-01-01

Kraft-AQ pulping lignin was sequentially fractionated by organic solvent extractions and the molecular properties of each fraction were characterized by chemical degradation, GPC, UV, FT-IR, 13C-NMR and thermal analysis. The average molecular weight and polydispersity of each lignin fraction increased with its hydrogen-bonding capacity (Hildebrand solubility parameter). In addition, the ratio of the non-condensed guaiacyl/syringyl units and the content of β-O-4 linkages increased with the increment of the lignin fractions extracted successively with hexane, diethylether, methylene chloride, methanol, and dioxane. Furthermore, the presence of the condensation reaction products was contributed to the higher thermal stability of the larger molecules. PMID:21152286

Comparison of bioavailable vanadium in alfalfa rhizosphere soil extracted by an improved BCR procedure and EDTA, HCl, and NaNO₃ single extractions in a pot experiment with V-Cd treatments.

PubMed

Yang, Jie; Teng, Yanguo; Zuo, Rui; Song, Liuting

2015-06-01

The BCR sequential extraction procedure was compared with EDTA, HCl, and NaNO3 single extractions for evaluating vanadium bioavailability in alfalfa rhizosphere soil. The amounts of vanadium extracted by these methods were in the following order: BCR (bioavailable V) > EDTA ≈ HCl > NaNO3. Both correlation analysis and stepwise regression were adopted to illustrate the extractable vanadium between different reagents. The correlation coefficients between extracted vanadium and the vanadium contents in alfalfa roots were R NaNO3 = 0.948, R HCl = 0.902, R EDTA = 0.816, and R bioavailable V = 0.819. The stepwise multiple regression equation of the NaNO3 extraction was the most significant at a 95 % confidence interval. The influence of pH, total organic carbon, and cadmium content of soil to vanadium bioavailability were not definite. In summary, both the BCR sequential extraction and the single extraction methods were valid approaches for predicting vanadium bioavailability in alfalfa rhizosphere soil, especially the single extractions.

Selenium speciation in phosphate mine soils and evaluation of a sequential extraction procedure using XAFS.

PubMed

Favorito, Jessica E; Luxton, Todd P; Eick, Matthew J; Grossl, Paul R

2017-10-01

Selenium is a trace element found in western US soils, where ingestion of Se-accumulating plants has resulted in livestock fatalities. Therefore, a reliable understanding of Se speciation and bioavailability is critical for effective mitigation. Sequential extraction procedures (SEP) are often employed to examine Se phases and speciation in contaminated soils but may be limited by experimental conditions. We examined the validity of a SEP using X-ray absorption spectroscopy (XAS) for both whole and a sequence of extracted soils. The sequence included removal of soluble, PO 4 -extractable, carbonate, amorphous Fe-oxide, crystalline Fe-oxide, organic, and residual Se forms. For whole soils, XANES analyses indicated Se(0) and Se(-II) predominated, with lower amounts of Se(IV) present, related to carbonates and Fe-oxides. Oxidized Se species were more elevated and residual/elemental Se was lower than previous SEP results from ICP-AES suggested. For soils from the SEP sequence, XANES results indicated only partial recovery of carbonate, Fe-oxide and organic Se. This suggests Se was incompletely removed during designated extractions, possibly due to lack of mineral solubilization or reagent specificity. Selenium fractions associated with Fe-oxides were reduced in amount or removed after using hydroxylamine HCl for most soils examined. XANES results indicate partial dissolution of solid-phases may occur during extraction processes. This study demonstrates why precautions should be taken to improve the validity of SEPs. Mineralogical and chemical characterizations should be completed prior to SEP implementation to identify extractable phases or mineral components that may influence extraction effectiveness. Sequential extraction procedures can be appropriately tailored for reliable quantification of speciation in contaminated soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

Partitioning of radionuclides and trace elements in phosphogypsum and its source materials based on sequential extraction methods.

PubMed

Santos, A J G; Mazzilli, B P; Fávaro, D I T; Silva, P S C

2006-01-01

Phosphogypsum is a waste produced by the phosphate fertilizer industry. Although phosphogypsum is mainly calcium sulphate dihydrate, it contains elevated levels of impurities, which originate from the source phosphate rock used in the phosphoric acid production. Among these impurities, radionuclides from 238U and 232Th decay series are of most concern due to their radiotoxicity. Other elements, such as rare earth elements (REE) and Ba are also enriched in the phosphogypsum. The bioavailability of radionuclides (226Ra, 210Pb and 232Th), rare earth elements and Ba to the surrounding aquatic system was evaluated by the application of sequential leaching of the phosphogypsum samples from the Brazilian phosphoric acid producers. The sequential extraction results show that most of the radium and lead are located in the "iron oxide" (non-CaSO4) fraction, and that only 13-18% of these radionuclides are distributed in the most labile fraction. Th, REE and Ba were found predominantly in the residual phase, which corresponds to a small fraction of the phosphate rock or monazite that did not react and to insoluble compounds such as sulphates, phosphates and silicates. It can be concluded that although all these elements are enriched in the phosphogypsum samples they are not associated with CaSO4 itself and therefore do not represent a threat to the surrounding aquatic environment.

Sequential weighted Wiener estimation for extraction of key tissue parameters in color imaging: a phantom study

NASA Astrophysics Data System (ADS)

Chen, Shuo; Lin, Xiaoqian; Zhu, Caigang; Liu, Quan

2014-12-01

Key tissue parameters, e.g., total hemoglobin concentration and tissue oxygenation, are important biomarkers in clinical diagnosis for various diseases. Although point measurement techniques based on diffuse reflectance spectroscopy can accurately recover these tissue parameters, they are not suitable for the examination of a large tissue region due to slow data acquisition. The previous imaging studies have shown that hemoglobin concentration and oxygenation can be estimated from color measurements with the assumption of known scattering properties, which is impractical in clinical applications. To overcome this limitation and speed-up image processing, we propose a method of sequential weighted Wiener estimation (WE) to quickly extract key tissue parameters, including total hemoglobin concentration (CtHb), hemoglobin oxygenation (StO2), scatterer density (α), and scattering power (β), from wide-band color measurements. This method takes advantage of the fact that each parameter is sensitive to the color measurements in a different way and attempts to maximize the contribution of those color measurements likely to generate correct results in WE. The method was evaluated on skin phantoms with varying CtHb, StO2, and scattering properties. The results demonstrate excellent agreement between the estimated tissue parameters and the corresponding reference values. Compared with traditional WE, the sequential weighted WE shows significant improvement in the estimation accuracy. This method could be used to monitor tissue parameters in an imaging setup in real time.

Sequential deconvolution from wave-front sensing using bivariate simplex splines

NASA Astrophysics Data System (ADS)

Guo, Shiping; Zhang, Rongzhi; Li, Jisheng; Zou, Jianhua; Xu, Rong; Liu, Changhai

2015-05-01

Deconvolution from wave-front sensing (DWFS) is an imaging compensation technique for turbulence degraded images based on simultaneous recording of short exposure images and wave-front sensor data. This paper employs the multivariate splines method for the sequential DWFS: a bivariate simplex splines based average slopes measurement model is built firstly for Shack-Hartmann wave-front sensor; next, a well-conditioned least squares estimator for the spline coefficients is constructed using multiple Shack-Hartmann measurements; then, the distorted wave-front is uniquely determined by the estimated spline coefficients; the object image is finally obtained by non-blind deconvolution processing. Simulated experiments in different turbulence strength show that our method performs superior image restoration results and noise rejection capability especially when extracting the multidirectional phase derivatives.

Pulsed counter-current ultrasound-assisted extraction and characterization of polysaccharides from Boletus edulis.

PubMed

You, Qinghong; Yin, Xiulian; Ji, Chaowen

2014-01-30

Four methods for extracting polysaccharides from Boletus edulis, namely, hot-water extraction, ultrasonic clearer extraction, static probe ultrasonic extraction, and pulsed counter-current probe ultrasonic extraction (CCPUE), were studied. Results showed that CCPUE has the highest extraction efficiency among the methods studied. Under optimal CCPUE conditions, a B. edulis polysaccharide (BEP) yield of 8.21% was obtained. Three purified fractions, BEP-I, BEP-II, and BEP-III, were obtained through sequential purification by DEAE-52 and Sephadex G-75 chromatography. The average molecular weights of BEP-I, BEP-II, and BEP-III were 10,278, 23,761, and 42,736 Da, respectively. The polysaccharides were mainly composed of xylose, mannose, galactose, and glucose; of these, mannose contents were the highest. The antioxidant activities of the BEPs were further investigated by measurement of their ability to scavenge DPPH and hydroxyl radicals as well as their reducing power. The results indicated that the BEPs have good antioxidant activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

Compositional Changes and Baking Performance of Rye Dough As Affected by Microbial Transglutaminase and Xylanase.

PubMed

Grossmann, Isabel; Döring, Clemens; Jekle, Mario; Becker, Thomas; Koehler, Peter

2016-07-20

Doughs supplemented with endoxylanase (XYL) and varying amounts of microbial transglutaminase (TG) were analyzed by sequential protein extraction, quantitation of protein fractions and protein types, and determination of water-extractable arabinoxylans. With increasing TG activity, the concentration of prolamins and glutelins decreased and increased, respectively, and the prolamin-to-glutelin ratio strongly declined. The overall amount of extractable protein decreased with increasing TG level showing that cross-linking by TG provided high-molecular-weight protein aggregates. The decrease of the high-molecular-weight arabinoxylan fraction and the concurrent increase of the medium-molecular-weight fraction confirmed the degradation of arabinoxylans by XYL. However, XYL addition did not lead to significant improved cross-linking of rye proteins by TG. Volume and crumb hardness measurements of bread showed increased protein connectivity induced by XYL and TG. Significant positive effects on the final bread quality were especially obtained by XYL addition.

Pollution potential leaching index as a tool to assess water leaching risk of arsenic in excavated urban soils.

PubMed

Li, Jining; Kosugi, Tomoya; Riya, Shohei; Hashimoto, Yohey; Hou, Hong; Terada, Akihiko; Hosomi, Masaaki

2018-01-01

Leaching of hazardous trace elements from excavated urban soils during construction of cities has received considerable attention in recent years in Japan. A new concept, the pollution potential leaching index (PPLI), was applied to assess the risk of arsenic (As) leaching from excavated soils. Sequential leaching tests (SLT) with two liquid-to-solid (L/S) ratios (10 and 20Lkg -1 ) were conducted to determine the PPLI values, which represent the critical cumulative L/S ratios at which the average As concentrations in the cumulative leachates are reduced to critical values (10 or 5µgL -1 ). Two models (a logarithmic function model and an empirical two-site first-order leaching model) were compared to estimate the PPLI values. The fractionations of As before and after SLT were extracted according to a five-step sequential extraction procedure. Ten alkaline excavated soils were obtained from different construction projects in Japan. Although their total As contents were low (from 6.75 to 79.4mgkg -1 ), the As leaching was not negligible. Different L/S ratios at each step of the SLT had little influence on the cumulative As release or PPLI values. Experimentally determined PPLI values were in agreement with those from model estimations. A five-step SLT with an L/S of 10Lkg -1 at each step, combined with a logarithmic function fitting was suggested for the easy estimation of PPLI. Results of the sequential extraction procedure showed that large portions of more labile As fractions (non-specifically and specifically sorbed fractions) were removed during long-term leaching and so were small, but non-negligible, portions of strongly bound As fractions. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of chemical pollution on forms of 137Cs, 90Sr and 239,240Pu in arctic soil studied by sequential extraction.

PubMed

Puhakainen, M; Riekkinen, I; Heikkinen, T; Jaakkola, T; Steinnes, E; Rissanen, K; Suomela, M; Thørring, H

2001-01-01

The aim of the present study was to determine the forms of 137Cs, 90Sr and 239,240Pu occurring in different soil horizons using sequential extraction of samples taken from four sites located along a pollution gradient from the copper-nickel smelter at Monchegorsk in the Kola Peninsula, Russia, and from a reference site in Finnish Lapland in 1997. A selective sequential-leaching procedure was employed using a modification of the method of Tessier, Cambell and Bisson ((1979). Analytical Chemistry, 51, 844-851). For 137Cs the organic (O) and uppermost mineral (E1) layer were studied, for 90Sr and 239,240Pu only the uppermost organic layer (Of). The fraction of 137Cs occurring in readily exchangeable form in the organic layer was about 50% at the reference site and decreased as a function of pollution, being 15% at the most polluted site in the Kola Peninsula. There was a clear positive correlation in the O layer between the distance from the smelter and the percentage of 137Cs extracted in the readily exchangeable fraction (Spearman correlation rsp = 0.7805, p = 0.0001), whereas in the E1 layer no correlation was evident. The distribution of 90Sr in the Of layer was similar at all sites, with the highest amounts occurring in exchangeable form and bound to organic matter, whereas stable Sr showed a somewhat different distribution with the highest amount in the oxide fraction. Most of the 239,240Pu was bound to organic matter. Chemical pollution affected the exchangeable fraction of 239,240Pu, which was about 1% at the most polluted site and 4-6% at the other sites.

Application of Sequential Extractions and X-ray Absorption Spectroscopy to Determine the Speciation of Chromium in Northern New Jersey Marsh Soils Developed in Chromite ore Processing Residue (COPR)

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

Elzinga, E.; Cirmo, A

2010-01-01

The Cr speciation in marsh soils developed in weathering chromite ore processing residue (COPR) was characterized using sequential extractions and synchrotron microbeam and bulk X-ray absorption spectroscopic (XAS) analyses. The sequential extractions suggested substantial Cr associated with reducible and oxidizable soil components, and significant non-extractable residual Cr. Notable differences in Cr speciation estimates from three extraction schemes underscore the operationally defined nature of Cr speciation provided by these methods. Micro X-ray fluorescence maps and {mu}-XAS data indicated the presence of {micro}m-sized chromite particles scattered throughout the weathered COPR matrix. These particles derive from the original COPR material, and have relativelymore » high resistance towards weathering, and therefore persist even after prolonged leaching. Bulk XAS data further indicated Cr(III) incorporated in Fe(OH){sub 3}, and Cr(III) associated with organic matter. The low Cr contents of the weathered material (200-850 ppm) compared to unweathered COPR (20,000-60,000 ppm) point to substantial Cr leaching during COPR weathering, with partial repartitioning of released Cr into secondary Fe(OH){sub 3} phases and organics. The effects of anoxia on Cr speciation, and the potential of active COPR weathering releasing Cr(VI) deeper in the profile require further study.« less

Applications of microencapsulated Bifidobacterium longum with Eleutherine americana in fresh milk tofu and pineapple juice.

PubMed

Phoem, Atchara N; Chanthachum, Suphitchaya; Voravuthikunchai, Supayang P

2015-04-03

Bifidobacterium longum was microencapsulated by extrusion technique and added in fresh milk tofu and pineapple juice. Microencapsulation of B. longum with Eleutherine americana extract, oligosaccharides extract, and commercial fructo-oligosaccharides was assessed for the bacterial survival after sequential exposure to simulated gastric and intestinal juices, and refrigeration storage. Microencapsulated B. longum with the extract and oligosaccharides extract in the food products showed better survival than free cells under adverse conditions. Sensory analysis demonstrated that the products containing co-encapsulated bacterial cells were more acceptable by consumers than free cells. Pineapple juice prepared with co-encapsulated cells had lower values for over acidification, compared with the juice with free cells added. This work suggested that microencapsulated B. longum with E. americana could enhance functional properties of fresh milk tofu and pineapple juice.

Applications of Microencapsulated Bifidobacterium Longum with Eleutherine Americana in Fresh Milk Tofu and Pineapple Juice

PubMed Central

Phoem, Atchara N.; Chanthachum, Suphitchaya; Voravuthikunchai, Supayang P.

2015-01-01

Bifidobacterium longum was microencapsulated by extrusion technique and added in fresh milk tofu and pineapple juice. Microencapsulation of B. longum with Eleutherine americana extract, oligosaccharides extract, and commercial fructo-oligosaccharides was assessed for the bacterial survival after sequential exposure to simulated gastric and intestinal juices, and refrigeration storage. Microencapsulated B. longum with the extract and oligosaccharides extract in the food products showed better survival than free cells under adverse conditions. Sensory analysis demonstrated that the products containing co-encapsulated bacterial cells were more acceptable by consumers than free cells. Pineapple juice prepared with co-encapsulated cells had lower values for over acidification, compared with the juice with free cells added. This work suggested that microencapsulated B. longum with E. americana could enhance functional properties of fresh milk tofu and pineapple juice. PMID:25854832

Structural and functional comparison of mobile and recalcitrant humic fractions from agricultural soils

USDA-ARS?s Scientific Manuscript database

Mobile humic acid (MHA) and calcium humate (CaHA) are humic fractions sequentially extracted from soil samples. MHA is extracted by dilute NaOH, and CaHA is subsequently extracted by dilute NaOH from the dilute HCl-washed soil residues of the first extraction. This chapter reviews the recent advance...

Chromium, nickel and vanadium mobility in soils derived from fluvioglacial sands.

PubMed

Agnieszka, Jeske; Barbara, Gworek

2012-10-30

The presented study was focused on soils developed from fluvioglacial sands from the Puszcza Borecka forest complex. The mobility of chromium, nickel and vanadium was evaluated with regard to litho- and pedogenic factors. The aim of the study was to determine with which soil constituents fractions of heavy metals are bound with particular attention drawn on the mobile fractions (F1+F2). Heavy metal fractions in the soils were determined using the sequential extraction method of Tessier et al. The purpose of sequential extraction methods to soil samples provides relevant information about possible toxicity when they are discharged into the soil environment. Chromium, nickel, and vanadium occurred predominantly in the fraction bound with iron and manganese oxides and in the residual fraction, thus showed low mobility. With regard to mobility, the elements studied can be arranged as follows: V

Effects of modified zeolite on the removal and stabilization of heavy metals in contaminated lake sediment using BCR sequential extraction.

PubMed

Wen, Jia; Yi, Yuanjie; Zeng, Guangming

2016-08-01

Sediment can be applied on land as a soil conditioner. However, toxic substances such as heavy metals within the sediment often lead to soil contamination if no proper management is conducted prior to land application. In order to reduce the bioavailable portion of heavy metals such as Pb, Cu, Zn and Cd, zeolite as a kind of stabilizer was investigated on the effect of metal stabilization in sediment. Zeolite was firstly modified and screened to get the best condition for removal of heavy metals. Results showed that the granulated zeolite with NaCl conditioning had the highest CEC and metal sorption. Using BCR sequential extraction, the selected modified zeolite effectively stabilized Pb, Cu, Zn and Cd in sediment to different extents. It was most suitable for Cd stabilization by reducing its acid exchangeable fraction while increasing the contents of the reducible and residual fractions. Modified zeolite also immobilized Cu, Zn and Pb in sediment by enhancing one stable fraction while decreasing the acid exchangeable fraction. Copyright © 2016 Elsevier Ltd. All rights reserved.

Extraction of heavy metals from MSW incinerator fly ash using saponins.

PubMed

Hong, K J; Tokunaga, S; Ishigami, Y; Kajiuchi, T

2000-08-01

An extraction process with saponins was evaluated for removing heavy metals from MSW (municipal solid waste) incinerator fly ashes. Two different fly ashes, A and B, were treated on a laboratory scale with three triterpene-glycoside type of saponins, M, Q, and T, in the pH range 4-9. The results were compared with those of the HCI and EDTA treatment. The treatment with saponins extracted 20-45% of Cr from the fly ashes. Saponins were also effective in extracting Cu from fly ash A attaining 50-60% extraction. Saponin T extracted 100% of Pb from fly ash A at pH around 4. The extraction of Zn with the saponin treatment was similar to that of the HCl treatment. Further, Cr, Cu, Pb, and Zn were fractionated by sequential extraction to investigate the effect of saponins on each fraction. Extraction behavior of other elements during the saponin treatment was also studied. The leaching test on the residues received after the saponin treatment showed that the fly ashes were successfully detoxified to meet the landfilling guideline.

Assessing the Selectivity of Extractant Solutions for Recovering Labile Arsenic Associated with Iron (Hydr)oxides and Sulfides in Sediments

EPA Science Inventory

Sequential extractions can provide analytical constraints on the identification of mineral phases that control arsenic speciation in sediments. Model solids were used in this study to evaluate different solutions designed to extract arsenic from relatively labile solid phases. ...

Raman Spectroscopy of Experimental Oral Carcinogenesis: Study on Sequential Cancer Progression in Hamster Buccal Pouch Model.

PubMed

Kumar, Piyush; Bhattacharjee, Tanmoy; Ingle, Arvind; Maru, Girish; Krishna, C Murali

2016-10-01

Oral cancers suffer from poor 5-year survival rates, owing to late detection of the disease. Current diagnostic/screening tools need to be upgraded in view of disadvantages like invasiveness, tedious sample preparation, long output times, and interobserver variances. Raman spectroscopy has been shown to identify many disease conditions, including oral cancers, from healthy conditions. Further studies in exploring sequential changes in oral carcinogenesis are warranted. In this Raman spectroscopy study, sequential progression in experimental oral carcinogenesis in Hamster buccal pouch model was investigated using 3 approaches-ex vivo, in vivo sequential, and in vivo follow-up. In all these studies, spectral changes show lipid dominance in early stages while later stages and tumors showed increased protein to lipid ratio and nucleic acids. On similar lines, early weeks of 7,12-dimethylbenz(a)anthracene-treated and control groups showed higher overlap and low classification. The classification efficiency increased progressively, reached a plateau phase and subsequently increased up to 100% by 14 weeks. The misclassifications between treated and control spectra suggested some changes in controls as well, which was confirmed by a careful reexamination of histopathological slides. These findings suggests Raman spectroscopy may be able to identify microheterogeneity, which may often go unnoticed in conventional biochemistry wherein tissue extracts are employed, as well as in histopathology. In vivo findings, quite comparable to gold-standard supported ex vivo findings, give further proof of Raman spectroscopy being a promising label-free, noninvasive diagnostic adjunct for future clinical applications. © The Author(s) 2015.

Effects on soil phosphorus dynamics of municipal solid waste compost addition to a burnt and unburnt forest soil.

PubMed

Turrión, María-Belén; Bueis, Teresa; Lafuente, Francisco; López, Olga; San José, Esther; Eleftheriadis, Alexandros; Mulas, Rafael

2018-06-12

The main aim of this research was to assess the effects of municipal solid waste compost (MSWC) addition to a burnt and unburnt calcareous soil, on the distribution of soil P forms in particle-size and extractable fractions. Three MSWC doses (1, 2 and 4% w/w) were added to burnt and unburnt soil samples and were incubated for 92 days at 29 °C and 75% of field capacity moisture. A particle-size fractionation followed by a sequential P extraction procedure was carried out. The burnt soil showed significantly lower concentrations of organic P forms (P org ) and significantly higher concentrations of stable P forms than the unburnt soil. Besides, in both burnt and unburnt soils, most P-forms presented higher concentrations in the clay fractions than in the sand and silt fractions, possibly due to the different proportions of microbial synthesized and plant-derived substances in the different particle-size fractions. Finer fractions of MSWC showed higher total P and P org concentrations than coarser fractions. Our results showed that the highest dose of MSWC was the most effective one for the rehabilitation of the burnt soil. MSWC amendment also caused an increase in soil P availability in the unburnt soil which initially contained relatively low levels of P. During the incubation process, a high proportion of organic P contained in the MSWC was mineralized into inorganic P forms. These forms were precipitated with Ca cations which are very abundant in these calcareous soils, significantly increasing the P fraction extracted by HCl in both amended soils. Hence, adding compost to the soil involved an increase in the available P reservoir in the long term. The combination of particle-size fractionation, chemical sequential extraction and incubation experiments can be a valuable tool for splitting soil phosphorus into different fractions regarding their availability in relation to short and long-term transformations in soil. Copyright © 2017 Elsevier B.V. All rights reserved.

Associations of cadmium, zinc, and lead in soils from a lead and zinc mining area as studied by single and sequential extractions.

PubMed

Anju, M; Banerjee, D K

2011-05-01

An exploratory study of the area surrounding a historical Pb-Zn mining and smelting area in Zawar, India, detected significant contamination of the terrestrial environment by heavy metals. Soils (n=87) were analyzed for pH, EC, total organic matter (TOM), Pb, Zn, Mn, and Cd levels. The statistical analysis indicated that the frequency distribution of the analyzed parameters for these soils was not normal. The median concentrations of metals in surface soils were: Pb 420.21 μ g/g, Zn 870.25 μ g/g, Mn 696.70 μ g/g, and Cd 2.09 μ g/g. Zn concentrations were significantly correlated with Cd (r=0.867), indicating that levels of Cd are dependent on Zn. However, pH, electrical conductivity and total organic matter were not correlated significantly with Cd, Pb, Zn, and Mn. To assess the potential mobility of Cd, Pb, and Zn in soils, single (EDTA) as well as sequential extraction scheme (modified BCR) were applied to representative (n=23) soil samples. The amount of Cd, Pb, and Zn extracted by EDTA and their total concentrations showed linear positive correlation, which are statistically significant (r values for Cd, Pb, and Zn being 0.901, 0.971, and 0.795, respectively, and P values being <0.001). The correlation coefficients indicate a strong relation between EDTA-extractable metal and total metal. These results appear to justify the use of 'total' metal contents as a useful preliminary indicator of areas where the risks of metal excess or deficiency are high. The EDTA extractability was maximum for Cd followed by Pb and Zn in soils from all the locations. As indicated by single extraction, the apparent mobility and potential bioavailability of metals in soils followed the order: Cd ≥ Pb > > Zn. Soil samples were sequentially extracted (modified BCR) so that solid pools of Cd, Zn, and Pb could be partitioned into four operationally defined fractions viz. acid-soluble, reducible, oxidizable, and residual. Cadmium was present appreciably (39.41%) in the acid-soluble fraction and zinc was predominantly associated (32.42%) with residual fraction. Pb (66.86%) and Zn (30.44%) were present mainly in the reducible fraction. Assuming that the mobility and bioavailability are related to solubility of geochemical forms of metals and decrease in the order of extraction, the apparent mobility and potential metal bioavailability for these contaminated soil samples is Cd > Zn > Pb.

Real time on-chip sequential adaptive principal component analysis for data feature extraction and image compression

NASA Technical Reports Server (NTRS)

Duong, T. A.

2004-01-01

In this paper, we present a new, simple, and optimized hardware architecture sequential learning technique for adaptive Principle Component Analysis (PCA) which will help optimize the hardware implementation in VLSI and to overcome the difficulties of the traditional gradient descent in learning convergence and hardware implementation.

Analysis of filter tuning techniques for sequential orbit determination

NASA Technical Reports Server (NTRS)

Lee, T.; Yee, C.; Oza, D.

1995-01-01

This paper examines filter tuning techniques for a sequential orbit determination (OD) covariance analysis. Recently, there has been a renewed interest in sequential OD, primarily due to the successful flight qualification of the Tracking and Data Relay Satellite System (TDRSS) Onboard Navigation System (TONS) using Doppler data extracted onboard the Extreme Ultraviolet Explorer (EUVE) spacecraft. TONS computes highly accurate orbit solutions onboard the spacecraft in realtime using a sequential filter. As the result of the successful TONS-EUVE flight qualification experiment, the Earth Observing System (EOS) AM-1 Project has selected TONS as the prime navigation system. In addition, sequential OD methods can be used successfully for ground OD. Whether data are processed onboard or on the ground, a sequential OD procedure is generally favored over a batch technique when a realtime automated OD system is desired. Recently, OD covariance analyses were performed for the TONS-EUVE and TONS-EOS missions using the sequential processing options of the Orbit Determination Error Analysis System (ODEAS). ODEAS is the primary covariance analysis system used by the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD). The results of these analyses revealed a high sensitivity of the OD solutions to the state process noise filter tuning parameters. The covariance analysis results show that the state estimate error contributions from measurement-related error sources, especially those due to the random noise and satellite-to-satellite ionospheric refraction correction errors, increase rapidly as the state process noise increases. These results prompted an in-depth investigation of the role of the filter tuning parameters in sequential OD covariance analysis. This paper analyzes how the spacecraft state estimate errors due to dynamic and measurement-related error sources are affected by the process noise level used. This information is then used to establish guidelines for determining optimal filter tuning parameters in a given sequential OD scenario for both covariance analysis and actual OD. Comparisons are also made with corresponding definitive OD results available from the TONS-EUVE analysis.

Dillenia suffruticosa exhibited antioxidant and cytotoxic activity through induction of apoptosis and G2/M cell cycle arrest.

PubMed

Armania, Nurdin; Yazan, Latifah Saiful; Musa, Siti Noorhidayah; Ismail, Intan Safinar; Foo, Jhi Biau; Chan, Kim Wei; Noreen, Husain; Hisyam, Abdul Hamid; Zulfahmi, Said; Ismail, Maznah

2013-03-27

Dillenia suffruticosa (Family: Dilleniaceae) locally known as Simpoh air has been reported to be used traditionally to treat cancerous growth. Therefore, the present study was attempted to investigate the antioxidant and cytotoxic properties of different parts (root, flower, fruit and leaf) of D. suffruticosa extracts. In this study, direct solvent extraction (aqueous and methanol) from different parts of D. suffruticosa (root, flower, fruit and leaf) were carried out. Antioxidant activities of D. suffruticosa extract were determined by using DPPH, ABTS FRAP and β-carotene bleaching assays. Cytotoxicity and cell cycle arrest of the active extract were determined using MTT assay and flow cytometer, respectively. Sequential solvent extraction (hexane, DCM, EtOAc, and MeOH) were also carried out in root of D. suffruticosa to further evaluate the antioxidant and cytotoxic activity of the different solvent extracts. Methanol (MeOH) root extract showed the highest TPC, antioxidant and cytotoxic activities (especially towards HeLa) compared to others (P<0.05). Based on the results, sequential solvent extraction (hexane, DCM, EtOAc and MeOH) was carried out in the roots of D. suffruticosa. MeOH extract exhibited the highest antioxidant activities among others and significantly correlated (P<0.05) with TPC, suggesting the important contribution of phenolic compounds to its antioxidant activity. On the other hand, the DCM and EtOAc exhibited higher cytotoxic activity to selected cancer cells (HeLa, MCF-7, MDA-MB-231, A549 and HT29) compared to others. In short, there is no established correlation between antioxidant and cytotoxic activities of D. suffruticosa extracts indicating that an agent with high antioxidant activities will not necessarily possesses good cytotoxic activities in return. Qualitative phytochemical screening of D. suffruticosa extracts suggested the presence of saponins, triterpenes, sterols, and polyphenolic compounds which are believed to contribute to the cytotoxic activities. It is suggested that the cytotoxicity of the active extracts in HeLa was due to the induction of apoptosis and cell cycle arrest at G2/M. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Sequential Extraction Results and Mineralogy of Mine Waste and Stream Sediments Associated With Metal Mines in Vermont, Maine, and New Zealand

USGS Publications Warehouse

Piatak, N.M.; Seal, R.R.; Sanzolone, R.F.; Lamothe, P.J.; Brown, Z.A.; Adams, M.

2007-01-01

We report results from sequential extraction experiments and the quantitative mineralogy for samples of stream sediments and mine wastes collected from metal mines. Samples were from the Elizabeth, Ely Copper, and Pike Hill Copper mines in Vermont, the Callahan Mine in Maine, and the Martha Mine in New Zealand. The extraction technique targeted the following operationally defined fractions and solid-phase forms: (1) soluble, adsorbed, and exchangeable fractions; (2) carbonates; (3) organic material; (4) amorphous iron- and aluminum-hydroxides and crystalline manganese-oxides; (5) crystalline iron-oxides; (6) sulfides and selenides; and (7) residual material. For most elements, the sum of an element from all extractions steps correlated well with the original unleached concentration. Also, the quantitative mineralogy of the original material compared to that of the residues from two extraction steps gave insight into the effectiveness of reagents at dissolving targeted phases. The data are presented here with minimal interpretation or discussion and further analyses and interpretation will be presented elsewhere.

Leaching behavior of rare earth elements in fort union lignite coals of North America

DOE PAGES

Laudal, Daniel A.; Benson, Steven A.; Addleman, Raymond Shane; ...

2018-03-30

Fort Union lignite coal samples were subjected to a series of aqueous leaching experiments to understand the extraction behavior of the rare earth elements (REE). This testing was aimed at understanding the modes of occurrence of the REE in the lignite coals, as well as to provide foundational data for development of rare earth extraction processes. In a first series of tests, a sequential leaching process was used to investigate modes of occurrence of the REE of select lignite coals. The tests involved sequential exposure to solvents consisting of water, ammonium acetate and dilute hydrochloric acid (HCl). The results indicatedmore » that water and ammonium acetate extracted very little of the REE, indicating the REE are not present as water soluble or ion-exchangeable forms. However, the data shows that a large percentage of the REE were extracted with the hydrochloric acid (80–95 wt%), suggesting presence in HCl-soluble mineral forms such as carbonates, and/or presence as organic complexes. A second series of tests was performed involving single-step leaching with dilute acids and various operating parameters, including acid type, acid concentration, acid/coal contact time and coal particle size. For select samples, additional tests were performed to understand the results of leaching, including float-sink density separations and humic acid extraction. The results have shown that the majority of REE in Fort Union lignites appear to be associated weakly with the organic matrix of the coals, most likely as coordination complexes of carboxylic acid groups. The light REE and heavy REE exhibit different behaviors, however. The extractable light REE appear to have association both in acid-soluble mineral forms and as organic complexes, whereas the extractable heavy REE appear to be almost solely associated with the organics. In conclusion, scandium behavior was notably different than yttrium and the lanthanides, and the data suggests the extractable content is primarily associated as acid-soluble mineral forms.« less

Leaching behavior of rare earth elements in fort union lignite coals of North America

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

Laudal, Daniel A.; Benson, Steven A.; Addleman, Raymond Shane

Fort Union lignite coal samples were subjected to a series of aqueous leaching experiments to understand the extraction behavior of the rare earth elements (REE). This testing was aimed at understanding the modes of occurrence of the REE in the lignite coals, as well as to provide foundational data for development of rare earth extraction processes. In a first series of tests, a sequential leaching process was used to investigate modes of occurrence of the REE of select lignite coals. The tests involved sequential exposure to solvents consisting of water, ammonium acetate and dilute hydrochloric acid (HCl). The results indicatedmore » that water and ammonium acetate extracted very little of the REE, indicating the REE are not present as water soluble or ion-exchangeable forms. However, the data shows that a large percentage of the REE were extracted with the hydrochloric acid (80–95 wt%), suggesting presence in HCl-soluble mineral forms such as carbonates, and/or presence as organic complexes. A second series of tests was performed involving single-step leaching with dilute acids and various operating parameters, including acid type, acid concentration, acid/coal contact time and coal particle size. For select samples, additional tests were performed to understand the results of leaching, including float-sink density separations and humic acid extraction. The results have shown that the majority of REE in Fort Union lignites appear to be associated weakly with the organic matrix of the coals, most likely as coordination complexes of carboxylic acid groups. The light REE and heavy REE exhibit different behaviors, however. The extractable light REE appear to have association both in acid-soluble mineral forms and as organic complexes, whereas the extractable heavy REE appear to be almost solely associated with the organics. In conclusion, scandium behavior was notably different than yttrium and the lanthanides, and the data suggests the extractable content is primarily associated as acid-soluble mineral forms.« less

Fractionation of metals by sequential extraction procedures (BCR and Tessier) in soil exposed to fire of wide temperature range

NASA Astrophysics Data System (ADS)

Fajkovic, Hana; Rončević, Sanda; Nemet, Ivan; Prohić, Esad; Leontić-Vazdar, Dana

2017-04-01

Forest fire presents serious problem, especially in Mediterranean Region. Effects of fire are numerous, from climate change and deforestation to loss of soil organic matter and changes in soil properties. One of the effects, not well documented, is possible redistribution and/or remobilisation of pollutants previously deposited in the soil, due to the new physical and chemical soil properties and changes in equilibrium conditions. For understanding and predicting possible redistribution and/or remobilisation of potential pollutants from soil, affected by fire different in temperature, several laboratory investigations were carried out. To evaluate the influence of organic matter on soil under fire, three soil samples were analysed and compared: (a) the one with added coniferous organic matter; (b) deciduous organic matter (b) and (c) soil without additional organic matter. Type of organic matter is closely related to pH of soil, as pH is influencing the mobility of some pollutants, e.g. metals. For that reason pH was also measured through all experimental steps. Each of mentioned soil samples (a, b and c) were heated at 1+3 different temperatures (25°C, 200°C, 500°C and 850°C). After heating, whereby fire effect on soil was simulated, samples were analysed by BCR protocol with the addition of a first step of sequential extraction procedure by Tessier and analysis of residual by aqua regia. Element fractionation of heavy metals by this procedure was used to determine the amounts of selected elements (Al, Cd, Cr, Co, Cu, Fe, Mn, Ni, Pb and Zn). Selected metal concentrations were determined using inductively coupled plasma atomic emission spectrometer. Further on, loss of organic matter was calculated after each heating procedure as well as the mineral composition. The mineral composition was determined using an X-ray diffraction. From obtained results, it can be concluded that temperature has an influence on concentration of elements in specific step of sequential extraction procedures. The first step of Tessier and BCR extraction of samples heated at 250°C and 500°C showed increasing trend of elemental concentrations. Results of these steps are especially important since they indicate mobile fraction of the elements (exchangeable, water- and acid-soluble fraction), which can easily affect the environment. Extraction procedures of samples combusted at 850°C showed that decrease in measured elemental content occurred. Some correlation is also noticed between type of organic matter, pH and concentration of analysed elements.

Cardiac conduction velocity estimation from sequential mapping assuming known Gaussian distribution for activation time estimation error.

PubMed

Shariat, Mohammad Hassan; Gazor, Saeed; Redfearn, Damian

2016-08-01

In this paper, we study the problem of the cardiac conduction velocity (CCV) estimation for the sequential intracardiac mapping. We assume that the intracardiac electrograms of several cardiac sites are sequentially recorded, their activation times (ATs) are extracted, and the corresponding wavefronts are specified. The locations of the mapping catheter's electrodes and the ATs of the wavefronts are used here for the CCV estimation. We assume that the extracted ATs include some estimation errors, which we model with zero-mean white Gaussian noise values with known variances. Assuming stable planar wavefront propagation, we derive the maximum likelihood CCV estimator, when the synchronization times between various recording sites are unknown. We analytically evaluate the performance of the CCV estimator and provide its mean square estimation error. Our simulation results confirm the accuracy of the proposed method and the error analysis of the proposed CCV estimator.

Antioxidant activity of extracts from the bark of Chamaecyparis lawsoniana (A. Murrary) Parl.

Treesearch

Heng Gao; Todd F. Shupe; Chung Y. Hse; Thomas L. Eberhardt

2006-01-01

The bark of Chamaecyparis lawsoniana (A. Murray) Parl. was extracted with methanol and sequentially partitioned with n-hexane, ethyl acetate, n-butanol and deionized water. The antioxidant activities of the four extracts were evaluated using the DPPH• and ABTS+• methods. The total phenolic...

A sequential extraction and hydrolysis approach to understand the chemical nature of soil water repellency

NASA Astrophysics Data System (ADS)

Mao, Jiefei; Dekker, Stefan C.; Nierop, Klaas G. J.

2014-05-01

Soil water repellency (SWR) biomarkers (SWR-biomarkers) are defined as hydrophobic organic compounds in soils causing SWR and originating from vegetation or microbes (Doerr et al., 2000). Free lipids and ester-bound biopolymers (cutins and suberins) are usually seen in the aliphatic part of soil organic matter (SOM) (Nierop, 1998). The method of sequential extraction can divide hydrophobic compounds into individual fractions with different characteristics. We aim to find out the SWR-biomarkers in soils within different fractions, investigate the effects of fractions on SWR and link them to their original sources. To extract free and ester-bound lipids from sandy soils, DCM (dichloromethane)/MeOH (methanol) and IPA(isopropanol)/NH3 were used in sequential steps. As a result, three fractions were obtained during these sequential experiments: a DCM/MeOH soluble fraction (D), a DCM-MeOH soluble (AS) fraction of IPA/NH3 extracts and its insoluble (AI) fraction. To date, research was limited to (organic) extractable fractions only. To investigate the DCM-MeOH insoluble part of IPA/NH3 extracts they were depolymerised by trans-methylation using BF3-MeOH. All fractions were analysed by gas chromatography-mass spectrometry. After DCM/MeOH extraction, water repellency of 80% of the soils studied increased while SWR of the other soils remained at the same level. Straight-chain fatty acids, alcohols and alkanes were the main compound groups in the D fractions. The distribution of fatty acids (C20-C32) and alcohols (C20-C32), both of which with an even-over-odd predominance suggest their source were higher plants, and so did the odd-over-even predominated alkanes. After extraction by IPA/NH3 , most soils became non-repellent. Both fatty acids (C16-C32) and alcohols (C16-C30) with an even-over-odd predominance were also found in the AS fractions, whereas no alkanes were detected. There were four main component groups identified in the AI fractions: fatty acids, alcohols, ω-hydroxy fatty acids and α,ω-dicarboxylic acids. Aside from fatty acids and alcohols, the latter two compound groups were considered as the main groups of monomers released from suberins. Therefore, suberin-derived compounds were most abundant in the AI fractions suggesting that plant roots could be the main source of AI fractions. We will present some of the relations between fractions/compounds and SWR to show that this approach may be an effective tool to improve our understanding of SWR mechanisms. We present relations between fractions/compounds from SOM with SWR to determine SWR-biomarkers. By assessing the origin of these biomarkers, we are able to understand how SWR is formed and in which circumstances they are mainly from leaves or roots (i.e. cutin or suberin). References: Doerr, S.H., Shakesby, R.A., Walsh, R.P.D., 2000. Soil water repellency: its causes, characteristics and hydro- geomorphological significance. Earth-Sci. Rev. 51, 33-65. Nierop, K.G.J., 1998. Origin of aliphatic compounds in a forest soil. Organic Geochemistry 29, 1009-1016.

The PMHT: solutions for some of its problems

NASA Astrophysics Data System (ADS)

Wieneke, Monika; Koch, Wolfgang

2007-09-01

Tracking multiple targets in a cluttered environment is a challenging task. Probabilistic Multiple Hypothesis Tracking (PMHT) is an efficient approach for dealing with it. Essentially PMHT is based on the method of Expectation-Maximization for handling with association conflicts. Linearity in the number of targets and measurements is the main motivation for a further development and extension of this methodology. Unfortunately, compared with the Probabilistic Data Association Filter (PDAF), PMHT has not yet shown its superiority in terms of track-lost statistics. Furthermore, the problem of track extraction and deletion is apparently not yet satisfactorily solved within this framework. Four properties of PMHT are responsible for its problems in track maintenance: Non-Adaptivity, Hospitality, Narcissism and Local Maxima. 1, 2 In this work we present a solution for each of them and derive an improved PMHT by integrating the solutions into the PMHT formalism. The new PMHT is evaluated by Monte-Carlo simulations. A sequential Likelihood-Ratio (LR) test for track extraction has been developed and already integrated into the framework of traditional Bayesian Multiple Hypothesis Tracking. 3 As a multi-scan approach, also the PMHT methodology has the potential for track extraction. In this paper an analogous integration of a sequential LR test into the PMHT framework is proposed. We present an LR formula for track extraction and deletion using the PMHT update formulae. As PMHT provides all required ingredients for a sequential LR calculation, the LR is thus a by-product of the PMHT iteration process. Therefore the resulting update formula for the sequential LR test affords the development of Track-Before-Detect algorithms for PMHT. The approach is illustrated by a simple example.

Dietary fibre components and pectin chemical features of peels during ripening in banana and plantain varieties.

PubMed

Happi Emaga, Thomas; Robert, Christelle; Ronkart, Sébastien N; Wathelet, Bernard; Paquot, Michel

2008-07-01

The effects of the ripeness stage of banana (Musa AAA) and plantain (Musa AAB) peels on neutral detergent fibre, acid detergent fibre, cellulose, hemicelluloses, lignin, pectin contents, and pectin chemical features were studied. Plantain peels contained a higher amount of lignin but had a lower hemicellulose content than banana peels. A sequential extraction of pectins showed that acid extraction was the most efficient to isolate banana peel pectins, whereas an ammonium oxalate extraction was more appropriate for plantain peels. In all the stages of maturation, the pectin content in banana peels was higher compared to plantain peels. Moreover, the galacturonic acid and methoxy group contents in banana peels were higher than in plantain peels. The average molecular weights of the extracted pectins were in the range of 132.6-573.8 kDa and were not dependant on peel variety, while the stage of maturation did not affect the dietary fibre yields and the composition in pectic polysaccharides in a consistent manner. This study has showed that banana peels are a potential source of dietary fibres and pectins.

Finding False Paths in Sequential Circuits

NASA Astrophysics Data System (ADS)

Matrosova, A. Yu.; Andreeva, V. V.; Chernyshov, S. V.; Rozhkova, S. V.; Kudin, D. V.

2018-02-01

Method of finding false paths in sequential circuits is developed. In contrast with heuristic approaches currently used abroad, the precise method based on applying operations on Reduced Ordered Binary Decision Diagrams (ROBDDs) extracted from the combinational part of a sequential controlling logic circuit is suggested. The method allows finding false paths when transfer sequence length is not more than the given value and obviates the necessity of investigation of combinational circuit equivalents of the given lengths. The possibilities of using of the developed method for more complicated circuits are discussed.

Environmental Risk Implications of Metals in Sludges from Waste Water Treatment Plants: The Discovery of Vast Stores of Metal-Containing Nanoparticles.

PubMed

Tou, Feiyun; Yang, Yi; Feng, Jingnan; Niu, Zuoshun; Pan, Hui; Qin, Yukun; Guo, Xingpan; Meng, Xiangzhou; Liu, Min; Hochella, Michael F

2017-05-02

Nanoparticle (NP) assessment in sludge materials, although of growing importance in eco- and biotoxicity studies, is commonly overlooked and, at best, understudied. In the present study, sewage sludge samples from across the mega-city of Shanghai, China were investigated for the first time using a sequential extraction method coupled with single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) to quantify the abundance of metal-containing NPs in the extraction fractions and transmission electron microscopy to specifically identify the nanophases present. In general, most sludges observed showed high concentrations of Cr, Cu, Cd, Ni, Zn, and Pb, exceeding the maximum permitted values in the national application standard of acid soil in China. NPs in these sludges contribute little to the volume and mass but account for about half of the total particle number. Based on electron microscopy techniques, various NPs were further identified, including Ti-, Fe-, Zn-, Sn-, and Pb-containing NPs. All NPs, ignored by traditional metal risk evaluation methods, were observed at a concentration of 10 7 -10 11 particles/g within the bioavailable fraction of metals. These results indicate the underestimate or misestimation in evaluating the environmental risks of metals based on traditional sequential extraction methods. A new approach for the environmental risk assessment of metals, including NPs, is urgently needed.

Sequential patterns of essential trace elements composition in Gracilaria verrucosa and its generated products

NASA Astrophysics Data System (ADS)

Izzati, Munifatul; Haryanti, Sri; Parman, Sarjana

2018-05-01

Gracilaria widely known as a source of essential trace elements. However this red seaweeds also has great potential for being developed into commercial products. This study examined the sequential pattern of essential trace elements composition in fresh Gracilaria verrucosa and a selection of its generated products, nemely extracted agar, Gracilaria salt and Gracilaria residue. The sample was collected from a brackish water pond, located in north part Semarang, Central Java. The collected sample was then dried under the sun, and subsequently processed into aformentioned generated products. The Gracilaria salt was obtain by soaking the sun dried Gracilaria overnight in fresh water overnight. The resulted salt solution was then boiled leaving crystal salt. Extracted agar was obtained with alkali agar extraction method. The rest of remaining material was considered as Gracilaria residue. The entire process was repeated 3 times. The compositin of trace elements was examined using ICP-MS Spectrometry. Collected data was then analyzed by ANOVA single factor. Resulting sequential pattern of its essential trace elements composition was compared. A regular table salt was used as controls. Resuts from this study revealed that Gracilaria verrucosa and its all generated products all have similarly patterned the composition of essential trace elements, where Mn>Zn>Cu>Mo. Additionally this pattern is similar to different subspecies of Gracilaria from different location and and different season. However, Gracilaria salt has distinctly different pattern of sequential essential trace elements composition compared to table salt.

Extraction Methods in Soil Phosphorus Characterisation

NASA Astrophysics Data System (ADS)

Soinne, Helena

2010-05-01

Extraction methods are widely used to assess the bioavailability of P and to characterise soil P reserves. Even though new and more sophisticated methods to characterise soil P are constantly developed the use of extraction methods is not likely to be replaced because of the relatively simple analytical equipment needed for the analysis. However, the large variety of extractants, pre-treatments and sample preparation procedures complicate the comparison of published results. In order to improve our understanding of the behaviour and cycling of P in soil, it is important to know the role of extracted P in the soil P cycle. The knowledge of the factors affecting the analytical outcome is a prerequisite for justified interpretation of the results. In this study, the effect of sample pre-treatment and properties of the used extractant on extractable molybdate-reactive phosphorus (MRP) and molybdate-unreactive phosphorus (MUP) was studied. Furthermore, the effect of sample preparation procedures prior the analysis on measured MRP and MUP was studied. Two widely used sequential extraction procedures were compared on their ability to show management induced differences on soil P. These results revealed that pre-treatments changed soil properties and air-drying was found to affect soil P, particularly extractable MUP, thought to represent organic P, by disrupting organic matter. This was evidenced by an increase in the water-extractable small-sized (<0.2 µm) P that, at least partly, took place at the expense of the large-sized (>0.2 µm) P. In addition to the effects of sample pre-treatment, the results showed that extractable organic P was sensitive to the chemical nature of the used extractant and to the sample preparation procedures employed prior to P analysis, including centrifugation and filtering of soil suspensions. Filtering may remove a major proportion of extractable MUP; therefore filtering cannot be recommended in the characterisation of solubilised MUP. However, extractants having high ionic strength may cause the organic molecules to collapse during centrifugation and thus affect the recovered concentration of MUP. These findings highlight the importance of characterising the nature of the MUP extracted with different extractants and acknowledging the sensitivity of MUP to analytical procedures when comparing published results. Widely used sequential fractionation procedures proved to be able to detect land-use -derived differences in the distribution of P among fractions of different solubilities. The results of this study demonstrate that, although the extraction methods do not reveal the biogeochemical function of a given P pool in soil, the extraction methods can be used to detect changes in soil P pools with different solubilities. To obtain the most benefit from extraction methods, we need a better understanding of the biological availability of P and the role of extracted P fraction in the P cycle in soils from different environments (climatic and weather) and land-uses.

Antimycobacterial, anti-inflammatory and genotoxicity evaluation of plants used for the treatment of tuberculosis and related symptoms in South Africa.

PubMed

Madikizela, B; Ndhlala, A R; Finnie, J F; Van Staden, J

2014-04-28

Emergence of drug-resistant tuberculosis strains and long duration of treatment has established an urgent need to search for new effective agents. The great floral diversity of South Africa has potential for producing new bioactive compounds, therefore pharmacological screening of plant extracts within this region offers much potential. To assess the in vitro antimycobacterial, anti-inflammatory and genotoxicity activity of selected plants that are used for the treatment of TB and related symptoms in South Africa. Ground plant materials from 10 plants were extracted sequentially with four solvents (petroleum ether, dichloromethane, 80% ethanol and water) and a total of 68 extracts were produced. A broth microdilution method was used to screen extracts against Mycobacterium tuberculosis H37Ra. The cyclooxygenase-2 (COX-2) enzyme was used to evaluate the anti-inflammatory activity of the extracts and the Salmonella microsome assay using two Salmonella typhimurium strains (TA98 and TA100) to establish genotoxicity. Six out of 68 extracts showed good antimycobacterial activity. Three extracts showed good inhibition (>70%) of COX-2 enzyme. All the extracts tested were non-genotoxic against the tested Salmonella strains. The results observed in this study indicate that some of the plants such as Abrus precatorius subsp. africanus, Ficus sur, Pentanisia prunelloides and Terminalia phanerophlebia could be investigated further against drug-resistant TB strains. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Insights into physicochemical and functional properties of polysaccharides sequentially extracted from onion (Allium cepa L.).

PubMed

Zhu, Dan-Ye; Ma, Yi-Long; Wang, Cai-Hong; Wang, Hao; Ren, Ya-Fei; Zhang, Jian-Guo; Thakur, Kiran; Wei, Zhao-Jun

2017-12-01

Onion polysaccharides (ACLP) were sequentially extracted with four different solvents (hot buffer, chelating agent, dilute alkaline and concentrated alkaline) and obtained four fractions, named as HBSS, CHSS, DASS and CASS, respectively. The present studies characterized the ACLP concerning its physicochemical and functional properties. Monosaccharides analysis revealed that mannose (81.68%) was the dominant sugar in HBSS and galactose (67.59%) was the most in CASS. Similarly, CHSS and DASS possessed mannose and galactose as major sugar, which were 25.80% and 31.37%, 20.33% and 33.96%, respectively. The obtained molecular weight of ACLPs were 7.702×10 3 (HBSS), 4.690×10 3 (CHSS), 4.943×10 3 (DASS) and 1.390×10 3 kDa (CASS). CASS resulted in the strongest solubility, fat-binding capacity, foam capacity and foam stability whereas, HBSS showed the highest thermal stability. DASS showed the best hygroscopicity and the best moisture retention was obtained by CHSS. Subsequently, the emulsifying activity and emulsifying stability were the highest for HBSS and the longest for of CASS, respectively. The rheological properties of CHSS exhibited the largest viscosity. Our results indicated that all factions could be considered as functional polysaccharides according to their respective characteristics, which have vast potential in food production. Copyright © 2017 Elsevier B.V. All rights reserved.

Preferential adsorption and surface precipitation of lead(II) ions onto anatase in artificially contaminated Dixie clay.

PubMed

Suzuki, Tasuma; Okita, Miyu; Kakoyama, Satoshi; Niinae, Masakazu; Nakata, Hideki; Fujii, Hiroshi; Tasaka, Yukio

2017-09-15

During TEM-EDS (transmission electron microscopy coupled with an X-ray energy dispersive spectrometer) analysis of Dixie clay artificially contaminated with Pb(II), we observed that Pb(II) was preferentially adsorbed and precipitated on the surface of TiO 2 . To deepen the understanding of the mechanism and importance of this phenomenon, batch sorption experiments, XANES (X-ray absorption near edge spectroscopy) analysis, and sequential extraction analysis were performed. The TiO 2 in Dixie clay was found to be anatase, and anatase showed a higher Pb(II) sorption propensity than rutile, α-FeOOH, and one of two MnO 2 investigated in this study. Our experimental results indicated that the Pb precipitates preferentially formed on the surface of anatase was Pb(II) hydroxide or Pb(II) oxide. Additionally, sequential extraction analysis showed that at least 32% and 42% of Pb(II) was sorbed onto anatase in the Dixie clay contaminated with a Pb content of 736mg Pb/kg and 1,958mg Pb/kg, respectively. These results demonstrated that in addition to Fe and Mn oxides that are well-known metal oxides that serve as sinks for Pb(II) in the soil environment, TiO 2 is also a metal oxide that controls the behavior and fate of Pb(II) in soils. Copyright © 2017 Elsevier B.V. All rights reserved.

Sequential ultrasound-microwave assisted acid extraction (UMAE) of pectin from pomelo peels.

PubMed

Liew, Shan Qin; Ngoh, Gek Cheng; Yusoff, Rozita; Teoh, Wen Hui

2016-12-01

This study aims to optimize sequential ultrasound-microwave assisted extraction (UMAE) on pomelo peel using citric acid. The effects of pH, sonication time, microwave power and irradiation time on the yield and the degree of esterification (DE) of pectin were investigated. Under optimized conditions of pH 1.80, 27.52min sonication followed by 6.40min microwave irradiation at 643.44W, the yield and the DE value of pectin obtained was respectively at 38.00% and 56.88%. Based upon optimized UMAE condition, the pectin from microwave-ultrasound assisted extraction (MUAE), ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE) were studied. The yield of pectin adopting the UMAE was higher than all other techniques in the order of UMAE>MUAE>MAE>UAE. The pectin's galacturonic acid content obtained from combined extraction technique is higher than that obtained from sole extraction technique and the pectin gel produced from various techniques exhibited a pseudoplastic behaviour. The morphological structures of pectin extracted from MUAE and MAE closely resemble each other. The extracted pectin from UMAE with smaller and more regular surface differs greatly from that of UAE. This has substantiated the highest pectin yield of 36.33% from UMAE and further signified their compatibility and potentiality in pectin extraction. Copyright © 2016 Elsevier B.V. All rights reserved.

Radionuclide studies of chronic schistosomal uropathy

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

Lamki, L.M.; Lamki, N.

1981-08-01

Fifty patients with chronic urinary tract schistosomiasis were studied with /sup 99m/Tc-DTPA. All had a flow study, sequential analog imaging, and digital imaging for 25-35 minutes (20-sec. frames). Time-activity curves (DTPA renograms) were extracted; 12 patients had /sup 131/I-Hippuran probe renograms as well. Renal changes included diminished perfusion and structural abnormalities ranging from minor calyceal dilatation to overt hydronephrosis. Ureteral changes included dilatation, tortuosity, and kinking. Marked distortion of the ureterovesical tunction was seen in some patients due to periureteral and perivesicular fibrosis, which is a major factor in upper urinary tract damage. Renograms showed varying obstruction and parenchymal damage.more » Nuclear medicine complements excretory urography and is sometimes preferable for visualization of the ureters. After the initial urogram, sequential DTPA scanning and renography are sufficient for follow-up.« less

Distribution and mode of occurrence of uranium in bottom ash derived from high-germanium coals.

PubMed

Sun, Yinglong; Qi, Guangxia; Lei, Xuefei; Xu, Hui; Li, Lei; Yuan, Chao; Wang, Yi

2016-05-01

The radioactivity of uranium in radioactive coal bottom ash (CBA) may be a potential danger to the ambient environment and human health. Concerning the limited research on the distribution and mode of occurrence of uranium in CBA, we herein report our investigations into this topic using a number of techniques including a five-step Tessier sequential extraction, hydrogen fluoride (HF) leaching, Siroquant (Rietveld) quantification, magnetic separation, and electron probe microanalysis (EPMA). The Tessier sequential extraction showed that the uranium in the residual and Fe-Mn oxide fractions was dominant (59.1% and 34.9%, respectively). The former was mainly incorporated into aluminosilicates, retained with glass and cristobalite, whereas the latter was especially enriched in the magnetic fraction, of which about 50% was present with magnetite (Fe3O4) and the rest in other iron oxides. In addition, the uranium in the magnetic fraction was 2.6 times that in the non-magnetic fraction. The experimental findings in this work may be important for establishing an effective strategy to reduce radioactivity from CBA for the protection of our local environment. Copyright © 2015. Published by Elsevier B.V.

Determination of distributions of Cd, Cu, and Pb concentrations in sediments of a Mexican reservoir to infer their environmental risk.

PubMed

Barceló-Quintal, Icela Dagmar; Solís-Correa, Hugo Eduardo; Avila-Pérez, Pedro; López-Galván, Edgar; Gómez-Salazar, Sergio; García-Albortante, Julisa

2012-07-01

The José Antonio Alzate Dam in the State of Mexico, Mexico, receives wastewaters from domestic, industrial, and agricultural activities through the Lerma River. Chemical and physicochemical characteristics of the water were determined. Sediment has been studied in order to define the importance of its influence on the reservoir's state as a whole. The quantification of the metals, Cd, Cu, and Pb in total forms and the geochemical distribution and the chemical mobility of these metals in sediment have been established using a chemical sequential extraction scheme. The three metals showed a common characteristic, being more abundant in fraction F6 (residual), but the other fractions of the geochemical distribution were variable depending on the metal. First, the contamination level was evaluated with the results of the total metals, using the criteria of EPA, Thomas and Murdoch, and the Ontario Ministry of Environment for sediment in water bodies. Subsequently, the risk was assessed using the same criteria but considering the results of sequential extractions, where the geochemical distribution of each metal allowed a better understanding of metal portions with more influence on the risk, in which Cu and Pb presented low risk, but not Cd.

Source and migration of dissolved manganese in the Central Nile Delta Aquifer, Egypt

NASA Astrophysics Data System (ADS)

Bennett, P. C.; El Shishtawy, A. M.; Sharp, J. M.; Atwia, M. G.

2014-08-01

Dissolved metals in waters in shallow deltaic sediments are one of the world's major health problems, and a prime example is arsenic contamination in Bangladesh. The Central Nile Delta Aquifer, a drinking water source for more than 6 million people, can have high concentrations of dissolved manganese (Mn). Standard hydrochemical analyses coupled with sequential chemical extraction is used to identify the source of the Mn and to identify the probable cause of the contamination. Fifty-nine municipal supply wells were sampled and the results compared with published data for groundwaters and surface waters. Drill cuttings from 4 wells were collected and analyzed by sequential chemical extraction to test the hypothesized Mn-generating processes. The data from this research show that the Mn source is not deep saline water, microbial reduction of Mn oxides at the production depth, or leakage from irrigation drainage ditches. Instead, Mn associated with carbonate minerals in the surficial confining layer and transported down along the disturbed well annulus of the municipal supply wells is the likely source. This analysis provides a basis for future hydrogeological and contaminant transport modeling as well as remediation-modification of well completion practices and pumping schedules to mitigate the problem.

White grape pomace extracts, obtained by a sequential enzymatic plus ethanol-based extraction, exert antioxidant, anti-tyrosinase and anti-inflammatory activities.

PubMed

Ferri, Maura; Rondini, Greta; Calabretta, Maria Maddalena; Michelini, Elisa; Vallini, Veronica; Fava, Fabio; Roda, Aldo; Minnucci, Giordano; Tassoni, Annalisa

2017-10-25

The present work aimed at optimizing a two-step enzymatic plus solvent-based process for the recovery of bioactive compounds from white grape (Vitis vinifera L., mix of Trebbiano and Verdicchio cultivars) pomace, the winemaking primary by-product. Phenolic compounds solubilised by water enzyme-assisted and ethanol-based extractions of wet (WP) and dried (DP) pomace were characterised for composition and tested for antioxidant, anti-tyrosinase and anti-inflammatory bioactivities. Ethanol treatment led to higher phenol yields than water extraction, while DP samples showed the highest capacity of releasing polyphenols, most probably as a positive consequence of the pomace drying process. Different compositions and bioactivities were observed between water and ethanol extracts and among different treatments and for the first time the anti-tyrosinase activity of V. vinifera pomace extracts, was here reported. Enzymatic treatments did not significantly improve the total amount of solubilised compounds; Celluclast in DP led to the recovery of extracts enriched in specific compounds, when compared to control. The best extracts (enzymatic plus ethanol treatment total levels) were obtained from DP showing significantly higher amounts of polyphenols, flavonoids, flavanols and tannins and exerted higher antioxidant and anti-tyrosinase activities than WP total extracts. Conversely, anti-inflammatory capacity was only detected in water (with and without enzyme) extracts, with WP samples showing on average a higher activity than DP. The present findings demonstrate that white grape pomace constitute a sustainable source for the extraction of phytochemicals that might be exploited as functional ingredients in the food, nutraceutical, pharmaceutical or cosmetic industries. Copyright © 2017 Elsevier B.V. All rights reserved.

Sequential extraction procedure for determination of uranium, thorium, radium, lead and polonium radionuclides by alpha spectrometry in environmental samples

NASA Astrophysics Data System (ADS)

Oliveira, J. M.; Carvalho, F. P.

2006-01-01

A sequential extraction technique was developed and tested for common naturally-occurring radionuclides. This technique allows the extraction and purification of uranium, thorium, radium, lead, and polonium radionuclides from the same sample. Environmental materials such as water, soil, and biological samples can be analyzed for those radionuclides without matrix interferences in the quality of radioelement purification and in the radiochemical yield. The use of isotopic tracers (232U, 229Th, 224Ra, 209Po, and stable lead carrier) added to the sample in the beginning of the chemical procedure, enables an accurate control of the radiochemical yield for each radioelement. The ion extraction procedure, applied after either complete dissolution of the solid sample with mineral acids or co-precipitation of dissolved radionuclide with MnO2 for aqueous samples, includes the use of commercially available pre-packed columns from Eichrom® and ion exchange columns packed with Bio-Rad resins, in altogether three chromatography columns. All radioactive elements but one are purified and electroplated on stainless steel discs. Polonium is spontaneously plated on a silver disc. The discs are measured using high resolution silicon surface barrier detectors. 210Pb, a beta emitter, can be measured either through the beta emission of 210Bi, or stored for a few months and determined by alpha spectrometry through the in-growth of 210Po. This sequential extraction chromatography technique was tested and validated with the analysis of certified reference materials from the IAEA. Reproducibility was tested through repeated analysis of the same homogeneous material (water sample).

Sleep to the beat: A nap favours consolidation of timing.

PubMed

Verweij, Ilse M; Onuki, Yoshiyuki; Van Someren, Eus J W; Van der Werf, Ysbrand D

2016-06-01

Growing evidence suggests that sleep is important for procedural learning, but few studies have investigated the effect of sleep on the temporal aspects of motor skill learning. We assessed the effect of a 90-min day-time nap on learning a motor timing task, using 2 adaptations of a serial interception sequence learning (SISL) task. Forty-two right-handed participants performed the task before and after a 90-min period of sleep or wake. Electroencephalography (EEG) was recorded throughout. The motor task consisted of a sequential spatial pattern and was performed according to 2 different timing conditions, that is, either following a sequential or a random temporal pattern. The increase in accuracy was compared between groups using a mixed linear regression model. Within the sleep group, performance improvement was modeled based on sleep characteristics, including spindle- and slow-wave density. The sleep group, but not the wake group, showed improvement in the random temporal, but especially and significantly more strongly in the sequential temporal condition. None of the sleep characteristics predicted improvement on either general of the timing conditions. In conclusion, a daytime nap improves performance on a timing task. We show that performance on the task with a sequential timing sequence benefits more from sleep than motor timing. More important, the temporal sequence did not benefit initial learning, because differences arose only after an offline period and specifically when this period contained sleep. Sleep appears to aid in the extraction of regularities for optimal subsequent performance. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Mammalian mucosal α-glucosidases coordinate with α-amylase in the initial starch hydrolysis stage to have a role in starch digestion beyond glucogenesis.

PubMed

Dhital, Sushil; Lin, Amy Hui-Mei; Hamaker, Bruce R; Gidley, Michael J; Muniandy, Anbuhkani

2013-01-01

Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph), and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary glucogenesis function.

Mammalian Mucosal α-Glucosidases Coordinate with α-Amylase in the Initial Starch Hydrolysis Stage to Have a Role in Starch Digestion beyond Glucogenesis

PubMed Central

Dhital, Sushil; Lin, Amy Hui-Mei; Hamaker, Bruce R.; Gidley, Michael J.; Muniandy, Anbuhkani

2013-01-01

Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph), and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary glucogenesis function. PMID:23638112

Stormwater Effects on Heavy Metal Sequestration in a Bioretention System in Culver City, California

NASA Astrophysics Data System (ADS)

Yousavich, D. J.; Ellis, A. S.; Dorsey, J.; Johnston, K.

2017-12-01

Rain Gardens, also referred to as bioretention or biofilters, are often used to capture or filter urban runoff before it drains into surface or groundwater systems. The Culver City Rain Garden (CCRG) is one such system that is designed to capture and filter runoff from approximately 11 acres of mixed-use commercial and industrial land before it enters Ballona Creek. The EPA has designated Ballona Creek as an impaired waterway and established Total Maximum Daily Loads for heavy metals. Previous research has utilized sequential extractions to establish trends in heavy metal sequestration for Cu, Pb, and Zn in bioretention media. The aim of this project is to evaluate if there is a difference in heavy metal sequestration between dry and wetted bioretention media. To characterize the stormwater at the site, influent and surface water were collected and analyzed for sulfate and heavy metals 3 times during the 2016-2017 storm season. Two soil cores from the CCRG were acquired in the summer of 2017 to analyze soil metal sequestration trends. They will be subjected to different wetting conditions, sectioned into discrete depths, and digested with an established sequential extraction technique. Surface water in the CCRG shows average Dissolved Oxygen during wet conditions of 2.92 mg/L and average pH of 6.1 indicating reducing conditions near the surface and the possible protonation of adsorption sites during wet weather conditions. Influent metal data indicate average dissolved iron levels near 1 ppm and influent Cu, Pb, and Zn levels near 0.05, 0.01, and 0.5 ppm respectively. This coupled with average surface water sulfate levels near 3 ppm indicates the potential for iron oxide and sulfide mineral formation depending on redox conditions. The sequential extraction results will elucidate whether heavy metals are adsorbed or are being sequestered in mineral formation. These results will allow for the inclusion of heavy metal sequestration trends in the design of further bioretention projects and maintenance of current sites.

The Development of Molybdenum Speciation as a Paleoredox Tool

NASA Astrophysics Data System (ADS)

Rodley, J.; Peacock, C.; Mosselmans, J. F. W.; Poulton, S.

2017-12-01

The redox state of the oceans has changed throughout geological time and an understanding of these changes is essential to elucidate links between ocean chemistry, climate and life. Due to its abundance in seawater and redox-sensitive nature, molybdenum has enormous potential as a paleoredox proxy. Although a significant amount of research has been done on molybdenum in ancient and modern sediments in terms of its concentrations and isotopic ratios there remains a limited understanding of the drawdown mechanisms of molybdenum under different redox conditions restricting its use in identifying a range of redox states. In order to address these uncertainties, we have developed a novel sequential extraction technique to examine molybdenum concentrations in six sediment fractions from modern samples that represent oxic, nitrogenous, ferruginous and euxinic environments. In addition we use µ-XRF and µ-XANES synchrotron spectroscopy to examine the molybdenum speciation within these fractions and environments. To interpret our µ-XANES data we have developed an extensive library of molybdenum XANES standards that represent molybdenum sequestration by the sediment fractions identified from the sequential extraction. To further verify our synchrotron results we developed a series of µ-XANES micro-column experiments to examine preferential uptake pathways of molybdenum to different sediment phases under a euxinic water column. The initial data from both the sequential extraction and µ-XANES methods indicate that molybdenum is not limited to a single burial pathway in any of the redox environments. We find that each of the redox environments can be characterised by a limited set of molybdenum phase associations, with molybdenum adsorption to pyrite likely the dominant burial pathway. These findings agree with existing research for molybdenum speciation in euxinic environments suggesting that both pyrite and sulphidised organic matter act as important molybdenum sinks. Our new research shows that pyrite is also an important sink for molybdenum in other redox environments.

Simultaneous application of chemical oxidation and extraction processes is effective at remediating soil Co-contaminated with petroleum and heavy metals.

PubMed

Yoo, Jong-Chan; Lee, Chadol; Lee, Jeung-Sun; Baek, Kitae

2017-01-15

Chemical extraction and oxidation processes to clean up heavy metals and hydrocarbon from soil have a higher remediation efficiency and take less time than other remediation processes. In batch extraction/oxidation process, 3% hydrogen peroxide (H 2 O 2 ) and 0.1 M ethylenediaminetetraacetic acid (EDTA) could remove approximately 70% of the petroleum and 60% of the Cu and Pb in the soil, respectively. In particular, petroleum was effectively oxidized by H 2 O 2 without addition of any catalysts through dissolution of Fe oxides in natural soils. Furthermore, heavy metals bound to Fe-Mn oxyhydroxides could be extracted by metal-EDTA as well as Fe-EDTA complexation due to the high affinity of EDTA for metals. However, the strong binding of Fe-EDTA inhibited the oxidation of petroleum in the extraction-oxidation sequential process because Fe was removed during the extraction process with EDTA. The oxidation-extraction sequential process did not significantly enhance the extraction of heavy metals from soil, because a small portion of heavy metals remained bound to organic matter. Overall, simultaneous application of oxidation and extraction processes resulted in highly efficient removal of both contaminants; this approach can be used to remove co-contaminants from soil in a short amount of time at a reasonable cost. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

Fontenot, Krystal; Naragoni, Srivatcha; Claville, Michelle

Kola acuminate, also known as Bizzy Nut or Kola Nut, is a natural product that contains bioactive chemicals that possess hormonal properties. The purpose of this study was to characterize the putative phytoestrogenic compounds present in Bizzy Nut for estrogenic-like activity. As an initial step, five extracts (E1 - hexane, E2 - ether, E3 - acetone, E4 - methanol and E5 - water) were sequentially generated using solid-liquid phase extraction and their bioactivity was examined in MCF-7, MDA-MB-468 and LNCaP cancer cell models. MTT cell viability, dye exclusion, caspase activity and microscopic assessment of apoptotic cells demonstrated that extracts ofmore » Bizzy were cytotoxic to MCF-7, MDA-MB 468 and LNCaP cells. In MCF-7 cells, the acetone extract (E3) at 100 ppm elicited a potent cytotoxic response with a growth-inhibitory concentration (GI{sub 50}) of 67 ppm. In contrast, E3 stimulated growth in LNCaP cells. The ether extract (E2) showed a dose-dependent cytotoxic response with a GI{sub 50} of 13 ppm in the LNCaP cell line. Examination of the apoptotic response induced by E2 and E3 paralleled the level of cell cytotoxicity observed in both cell lines. The methanol extract (E4) was the only extract that showed a time-, dose-, and estrogen-receptor-dependent stimulation of pS2 gene expression. On the other hand, the acetone extract (E3), which showed the highest degree of cytotoxicity, showed no transcription stimulation of pS2 in MCF-7 cells. Altogether, these data indicate that Bizzy contains unique active hormonal compounds that have specific biological properties that are cell line-dependent.« less

Protein classification using sequential pattern mining.

PubMed

Exarchos, Themis P; Papaloukas, Costas; Lampros, Christos; Fotiadis, Dimitrios I

2006-01-01

Protein classification in terms of fold recognition can be employed to determine the structural and functional properties of a newly discovered protein. In this work sequential pattern mining (SPM) is utilized for sequence-based fold recognition. One of the most efficient SPM algorithms, cSPADE, is employed for protein primary structure analysis. Then a classifier uses the extracted sequential patterns for classifying proteins of unknown structure in the appropriate fold category. The proposed methodology exhibited an overall accuracy of 36% in a multi-class problem of 17 candidate categories. The classification performance reaches up to 65% when the three most probable protein folds are considered.

Sequential high pressure extractions applied to recover piceatannol and scirpusin B from passion fruit bagasse.

PubMed

Viganó, Juliane; Aguiar, Ana C; Moraes, Damila R; Jara, José L P; Eberlin, Marcos N; Cazarin, Cinthia B B; Maróstica, Mário R; Martínez, Julian

2016-07-01

Passion fruit seeds are currently discarded on the pulp processing but are known for their high piceatannol and scirpusin B contents. Using pressurized liquid extraction (PLE), these highly valuable phenolic compounds were efficiently extracted from defatted passion fruit bagasse (DPFB). PLE was performed using mixtures of ethanol and water (50 to 100% ethanol, w/w) as solvent, temperatures from 50 to 70°C and pressure at 10MPa. The extraction methods were compared in terms of the global yield, total phenolic content (TPC), piceatannol content and the antioxidant capacity of the extracts. The DPFB extracts were also compared with those from non-defatted passion fruit bagasse (nDPFB). Identification and quantification of piceatannol were performed using UHPLC-MS/MS. The results showed that high TPC and piceatannol content were achieved for the extracts obtained from DPFB through PLE at 70°C and using 50 and 75% ethanol as the solvent. The best PLE conditions for TPC (70°C, 75% ethanol) resulted in 55.237mgGAE/g dried and defatted bagasse, whereas PLE at 70°C and 50% ethanol achieved 18.590mg of piceatannol/g dried and defatted bagasse, and such yields were significantly higher than those obtained using conventional extraction techniques. The antioxidant capacity assays showed high correlation with the TPC (r>0.886) and piceatannol (r>0.772). The passion fruit bagasse has therefore proved to be a rich source of piceatannol and PLE showed high efficiency to recover phenolic compounds from defatted passion fruit bagasse. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of Traditional Indian Antidiabetic Medicinal Plants for Human Pancreatic Amylase Inhibitory Effect In Vitro

PubMed Central

Ponnusamy, Sudha; Ravindran, Remya; Zinjarde, Smita; Bhargava, Shobha; Ravi Kumar, Ameeta

2011-01-01

Pancreatic α-amylase inhibitors offer an effective strategy to lower the levels of post prandial hyperglycemia via control of starch breakdown. Eleven Ayurvedic Indian medicinal plants with known hypoglycemic properties were subjected to sequential solvent extraction and tested for α-amylase inhibition, in order to assess and evaluate their inhibitory potential on pancreatic α-amylase. Analysis of 91 extracts, showed that 10 exhibited strong Human Pancreatic Amylase (HPA) inhibitory potential. Of these, 6 extracts showed concentration dependent inhibition with IC50 values, namely, cold and hot water extracts from Ficus bengalensis bark (4.4 and 125 μgmL−1), Syzygium cumini seeds (42.1 and 4.1 μgmL−1), isopropanol extracts of Cinnamomum verum leaves (1.0 μgmL−1) and Curcuma longa rhizome (0.16 μgmL−1). The other 4 extracts exhibited concentration independent inhibition, namely, methanol extract of Bixa orellana leaves (49 μgmL−1), isopropanol extract from Murraya koenigii leaves (127 μgmL−1), acetone extracts from C. longa rhizome (7.4 μgmL−1) and Tribulus terrestris seeds (511 μgmL−1). Thus, the probable mechanism of action of the above fractions is due to their inhibitory action on HPA, thereby reducing the rate of starch hydrolysis leading to lowered glucose levels. Phytochemical analysis revealed the presence of alkaloids, proteins, tannins, cardiac glycosides, flavonoids, saponins and steroids as probable inhibitory compounds. PMID:20953430

Retinal blood vessel extraction using tunable bandpass filter and fuzzy conditional entropy.

PubMed

Sil Kar, Sudeshna; Maity, Santi P

2016-09-01

Extraction of blood vessels on retinal images plays a significant role for screening of different opthalmologic diseases. However, accurate extraction of the entire and individual type of vessel silhouette from the noisy images with poorly illuminated background is a complicated task. To this aim, an integrated system design platform is suggested in this work for vessel extraction using a sequential bandpass filter followed by fuzzy conditional entropy maximization on matched filter response. At first noise is eliminated from the image under consideration through curvelet based denoising. To include the fine details and the relatively less thick vessel structures, the image is passed through a bank of sequential bandpass filter structure optimized for contrast enhancement. Fuzzy conditional entropy on matched filter response is then maximized to find the set of multiple optimal thresholds to extract the different types of vessel silhouettes from the background. Differential Evolution algorithm is used to determine the optimal gain in bandpass filter and the combination of the fuzzy parameters. Using the multiple thresholds, retinal image is classified as the thick, the medium and the thin vessels including neovascularization. Performance evaluated on different publicly available retinal image databases shows that the proposed method is very efficient in identifying the diverse types of vessels. Proposed method is also efficient in extracting the abnormal and the thin blood vessels in pathological retinal images. The average values of true positive rate, false positive rate and accuracy offered by the method is 76.32%, 1.99% and 96.28%, respectively for the DRIVE database and 72.82%, 2.6% and 96.16%, respectively for the STARE database. Simulation results demonstrate that the proposed method outperforms the existing methods in detecting the various types of vessels and the neovascularization structures. The combination of curvelet transform and tunable bandpass filter is found to be very much effective in edge enhancement whereas fuzzy conditional entropy efficiently distinguishes vessels of different widths. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

BCR®-701: a review of 10-years of sequential extraction analyses.

PubMed

Sutherland, Ross A

2010-11-08

A detailed quantitative analysis was performed on data presented in the literature that focused on the sequential extraction of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) from the certified reference material BCR-701 (lake sediment) using the three-step harmonized BCR(®) procedure. The accuracy of data reported in the literature, including precision and different measures of trueness, was assessed relative to the certified values for BCR-701. Forty data sets were accepted following extreme outlier removal, and statistically summarized with measures of central tendency, dispersion, and distribution form. In general, literature data were similar in their measurement precision to the expert laboratories used to certify the trace element contents in BCR-701. The overall median precision for literature reported data was 10% (range 6-19%), compared to certifying laboratories of 9% (range 4-33%). One measure of literature data trueness was assessed via a confirmatory approach using a robust bootstrap method. Only 22% of the comparisons indicated significantly different (all were lower) concentrations reported in the literature compared to certified values. The question of whether the differences are practically significant for environmental studies is raised. Bias was computed as a measure of trueness, and literature data were more frequently negatively biased, indicating lower concentrations reported in the literature for the six trace elements for the three-step sequential procedure compared to the certified values. However, 95% confidence intervals about the average bias for the 18 comparisons indicated only four instances when a mean bias of 0 (i.e., measured=certified) was not incorporated-suggesting statistical difference. Finally, Z-scores incorporating a Horwitz-type function were used to assess the general trueness of laboratory data. Of the 468 laboratory Z-score values computed, 92% were considered to be satisfactory, 5% were questionable, and 3% were unsatisfactory. A detailed examination of the methodology sections of the various studies showed that despite claiming adherence to the harmonized BCR sequential extraction protocol, significant deviations were commonly observed; particularly in moisture correction, sample mass, centrifugation specifics, shaking specifics, and incorporation of filtration. It is likely that failure to strictly adhere to the protocol adversely impacted accuracy, by increasing the degree of imprecision and resulting in more discrepant trueness values. Copyright © 2010 Elsevier B.V. All rights reserved.

Simultaneous determination of mequindox, quinocetone, and their major metabolites in chicken and pork by UPLC-MS/MS

USDA-ARS?s Scientific Manuscript database

This research presents a sensitive and confirmatory multi-residue method for mequindox (MEQ), quinocetone (QCT), and their 11 metabolites in chicken and pork samples. After extracted with acetonitrile-ethyl acetate, acidulated, and extracted again with ethyl acetate sequentially, each sample was pu...

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, PCB DETECTION TECHNOLOGY, HYBRIZYME DELFIA TM ASSAY

EPA Science Inventory

The DELFIA PCB Assay is a solid-phase time-resolved fluoroimmunoassay based on the sequential addition of sample extract and europium-labeled PCB tracer to a monoclonal antibody reagent specific for PCBs. In this assay, the antibody reagent and sample extract are added to a strip...

Evaluating CO2 mineralization capacity of sedimentary rock Using BCR sequential extraction procedures

NASA Astrophysics Data System (ADS)

Yang, Gang-Ting; Yu, Chi-Wen; Yang, Hsiao-Ming; Chiao, Chung-Hui; Yang, Ming-Wei

2015-04-01

To relief the high concentration of carbon dioxide in the atmosphere, carbon capture and storage (CCS) is gradually becoming an important concept to reduce greenhouse gas emissions. In IPCC Special Report on CCS, the storage mechanisms for geological formations are categorized into structural/stratigraphic, hydrodynamic and geochemical trappings. Geochemical trapping is considered as a storage mechanism, which can further increase storage capacity, effectiveness and security in terms of permanent CO2 sequestration. The injected CO2 can have geochemical interactions with pore fluid and reservoir rocks and transform into minerals. It is important to evaluate the capacity of reservoir rock for sequestrating CO2. In this study, sedimentary rock samples were collected from a 2-km-deep well in Midwestern Taiwan; and, the BCR sequential extraction experiments developed by European Union Measurement and Testing Programme were conducted. BCR was designed for extracting three major phases from soil, including exchangeable phase and carbonates (the first stage), reducible phase (the second stage) and oxidizable phase (the third stage). The chemistry of extracted solutions and rock residues were measured with ICP-MS and XRF, respectively. According to the results of XRF, considerable amounts of calcium and iron can be extracted by BCR procedures but other cations are negligible. In general, shale has a higher capacity of CO2 sequestration than sandstone. The first stage of extraction can release about 6 (sandstone) to 18.5 (shale) g of calcium from 1 kg rock, which are equivalent to 6.6 and 20.4 g CO2/kg rock, respectively. In the second stage extraction, 0.71 (sandstone) to 1.38 (shale) g/kg rock of iron can be released and can mineralized 0.56 to 1.08 g CO2/kg rock. However, there are no considerable cations extracted in the third stage of BCR as shown by the XRF analysis. In addition, the results of ICP-MS show that Mg can be released in the order of 10-3 g from 1 kg rock while cations of Zn, Co, Ni, Cd, Pb, Cu and Ba are in the order of 10-4 g.

Radionuclide studies of chronic schistosomal uropathy. [/sup 99m/Tc-DTPA; /sup 131/I-hippuran

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

Lamki, L.M.; Lamki, N.

1981-08-01

Fifty patients with chronic urinary tract schistosomiasis were studied with /sup 99m/Tc-DTPA. All had a flow study, sequential analog imaging, and digital imaging for 25 to 35 min (20-sec frames). Time-activity curves (DTPA renograms) were extracted; 12 patients had /sup 131/I-Hippuran probe renograms as well. Renal changes included diminished perfusion and structural abnormalities ranging from minor calyceal dilatation to overt hydronephrosis. Ureteral changes included dilatation, tortuosity, and kinking. Marked distortion of the ureterovesical junction was seen in some patients due to periureteral and perivesicular fibrosis, which is a major factor in upper urinary tract damage. Renograms showed varying obstruction andmore » parenchymal damage. Nuclear medicine complements excretory urography and is sometimes preferable for visualization of the ureters. After the initial urogram, sequential DTPA scanning and renography are sufficient for follow-up.« less

Evaluation of the Sequential Spot Sampler (S3) for time-resolved measurement of PM2.5 sulfate and nitrate through lab and field measurements

NASA Astrophysics Data System (ADS)

Hecobian, A.; Evanoski-Cole, A.; Eiguren-Fernandez, A.; Sullivan, A. P.; Lewis, G. S.; Hering, S. V.; Collett, J. L., Jr.

2016-02-01

The Sequential Spot Sampler (S3), a newly developed instrument to collect aerosols for time-resolved chemical composition measurements, was evaluated in the laboratory and field for the measurement of particulate sulfate and nitrate. The S3 uses a multi-temperature condensation growth tube to grow individual aerosols to droplets which are then deposited as a ˜ 1 mm diameter dry spot at the end of the growth tube in a 100 µL well of a multi-well plate. The well plate advances automatically to provide a sequence of time-resolved samples. The collected aerosols are subsequently analyzed in the laboratory. The sample is concentrated during the collection process, and the laboratory extraction and analysis steps can be automated. The well plate, as received from the field, is placed onto a needle-based autosampler that adds liquid for sample extraction and injects sample extract from each well onto an ion chromatograph for analysis. Laboratory evaluation for sulfate and nitrate ions showed that poly ether ether ketone (PEEK) used as well plate material does not contribute any artifacts; a 60 min extraction procedure leads to the recovery of sulfate and nitrate from the dry spots at above 95 % extraction efficiency; and samples stored frozen and analyzed up to 23 months later show less than a 10 % change in sulfate and nitrate concentrations. The limit of detection was 0.5 µg m-3 for sulfate and 0.2 µg m-3 for nitrate for a 1 h sampling period. In a month-long field study conducted in southern California, two S3s were deployed alongside a URG denuder-filter-pack and a Particle-Into-Liquid Sampler combined with an Ion Chromatograph (PILS-IC). Collocated S3 sampler concentrations compared by linear regression show good agreement, with r2 = 0.99 and slope = 0.99 (±0.004) µg m-3 for sulfate and r2 = 0.99 and slope = 1.0 (±0.006) µg m-3 for nitrate. When compared to the URG denuder-filter-pack and the PILS-IC, the S3 sulfate and nitrate concentrations yielded correlations above 0.84 for the square of the correlation coefficient and regression slopes close to 1.

Secretome analysis of Trichoderma reesei and Aspergillus niger cultivated by submerged and sequential fermentation processes: Enzyme production for sugarcane bagasse hydrolysis.

PubMed

Florencio, Camila; Cunha, Fernanda M; Badino, Alberto C; Farinas, Cristiane S; Ximenes, Eduardo; Ladisch, Michael R

2016-08-01

Cellulases and hemicellulases from Trichoderma reesei and Aspergillus niger have been shown to be powerful enzymes for biomass conversion to sugars, but the production costs are still relatively high for commercial application. The choice of an effective microbial cultivation process employed for enzyme production is important, since it may affect titers and the profile of protein secretion. We used proteomic analysis to characterize the secretome of T. reesei and A. niger cultivated in submerged and sequential fermentation processes. The information gained was key to understand differences in hydrolysis of steam exploded sugarcane bagasse for enzyme cocktails obtained from two different cultivation processes. The sequential process for cultivating A. niger gave xylanase and β-glucosidase activities 3- and 8-fold higher, respectively, than corresponding activities from the submerged process. A greater protein diversity of critical cellulolytic and hemicellulolytic enzymes were also observed through secretome analyses. These results helped to explain the 3-fold higher yield for hydrolysis of non-washed pretreated bagasse when combined T. reesei and A. niger enzyme extracts from sequential fermentation were used in place of enzymes obtained from submerged fermentation. An enzyme loading of 0.7 FPU cellulase activity/g glucan was surprisingly effective when compared to the 5-15 times more enzyme loadings commonly reported for other cellulose hydrolysis studies. Analyses showed that more than 80% consisted of proteins other than cellulases whose role is important to the hydrolysis of a lignocellulose substrate. Our work combined proteomic analyses and enzymology studies to show that sequential and submerged cultivation methods differently influence both titers and secretion profile of key enzymes required for the hydrolysis of sugarcane bagasse. The higher diversity of feruloyl esterases, xylanases and other auxiliary hemicellulolytic enzymes observed in the enzyme mixtures from the sequential fermentation could be one major reason for the more efficient enzyme hydrolysis that results when using the combined secretomes from A. niger and T. reesei. Copyright © 2016 Elsevier Inc. All rights reserved.

Xylose-rich polysaccharides from the primary walls of embryogenic cell line of Pinus caribaea.

PubMed

Mollard, A; Domon, J M; David, H; Joseleau, J P

1997-08-01

Embryogenic cell lines of Pinus caribaea were isolated from somatic embryogenesis from zygotic embryos. Previous studies showed that the proteins and glycoproteins were characteristic of the embryogenic state. In the present work we were seeking typical feature in the polysaccharide from the cell walls of embryogenic calli at nine days of culture. Sequential extraction with water, ammonium oxalate, dimethyl sulfoxide, sodium borohydride and 4.3 M potassium hydroxide revealed that the extracted polysaccharides contained high proportions of arabinose and significant amounts of xylose. Fractionation of the hydrosoluble polymers on DEAE cellulose afforded a xylose-rich fraction (80% xylose, 24% glucose and lower properties of fucose and mannose). Methylation analysis and 13C-NMR spectra showed that the glycan backbone consisted of beta 1 --> 4 linked xylosyl residues Similar study of the fractions extracted respectively with DMSO and 4.3 M KOH showed the presence of polydisperse glycoxylans but excluded the presence of xyloglucan in significant amount. This could be a characteristic feature of embryogenic cells walls of Pinus caribaea or could be typical of cells grown as calluses. In the various fractions obtained from DEAE cellulose chromatography of the alkaline extract the infrequent occurrence of fucoxylans beside an arabinogalactan showed again the unusual nature of the cell wall polymers of this embryogenic lines, which seems to differ greatly from those found in the primary wall of cells from suspension cultures.

Effect of Mouriri pusa extracts on experimentally induced gastric lesions in rodents: role of endogenous sulfhydryls compounds and nitric oxide in gastroprotection.

PubMed

Andreo, Marcio Adriano; Ballesteros, Kátia Verônica Rodríguez; Hiruma-Lima, Clélia Akiko; Machado da Rocha, Lúcia Regina; Souza Brito, Alba Regina Monteiro; Vilegas, Wagner

2006-10-11

Several plants are used in folk medicine to treat gastrointestinal disorders. Mouriri pusa Gardn. (Melastomataceae) is a medicinal plant commonly used in the central region of Brazil against gastric ulcer. Two organic extracts methanolic (MeOH) and dichloromethane (DCM) obtained by sequential extraction from the leaves of Mouriri pusa were evaluated for their ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3M HCl/60% EtOH, absolute ethanol, non-steroidal anti-inflammatory drug, stress and pylorus ligature) in mice and rats. The best results were obtained after pretreatment with MeOH extract whereas the DCM extract did not show the same significant antiulcerogenic activity. No acute toxicity was observed in animals treated with 5 g/kg, p.o. of MeOH extract. The mechanism involving the antiulcerogenic action of MeOH extract seemed to be related to NO generation and also suggested the effective participation of endogenous sulfhydryl group in the gastroprotective action. Phytochemical investigation of the MeOH extract of Mouriri pusa yielded tannins, flavonoids and (-)-epicatechin. The presence of these phenolic compounds probably would explain the antiulcerogenic effect of the polar extract of Mouriri pusa leaves.

Evaluation of the dynamic mobilization of vanadium in tributary sediments of the Three Gorges Reservoir after water impoundment

NASA Astrophysics Data System (ADS)

Gao, Bo; Gao, Li; Zhou, Yang; Xu, Dongyu; Zhao, Xingjuan

2017-08-01

The Three Gorges Reservoir (TGR) is the largest water resource protection zone in China, and environmental safety is crucial to its operation. For both aqueous and sediment phases, diffusive gradients in thin films (DGT), total vanadium (V) concentration (CTotal-V), and community Bureau of Reference (BCR) sequential extraction data were used to measure the pollution characteristics, horizontal and vertical distributions of DGT-labile V, and the dynamic mobilization of V in a typical tributary (the Meixi River) of the TGR. The results showed that CTotal-V in the surface sediments were obviously higher than the background values in sediment and soil, indicating a potential anthropogenic input of V in this area. A positive relationship was found between total organic carbon (TOC) and CTotal-V in the sediments, indicating that the pollution characteristics of V were associated with TOC. In addition, horizontal and vertical distributions of the fluxes of DGT-labile V (FDGT-V) varied among the four DGT probes. In the same DGT probe, the horizontal distributions (0-6 mm, 6-12 mm and 12-18 mm) of FDGT-V were similar in the overlying water; however, the values showed a poor coincidence with those recorded in the sediment. The vertical distribution of FDGT-V in the same DGT probe showed similar tendencies. In fact, CDGT-V is significantly negatively correlated with CDGT-Fe, demonstrating that V had an inversely diffusive tendency with Fe. Moreover, diffusion fluxes of V at the sediment-water interface illustrated that the release characteristics of V varied among the sampling sites. In addition, the BCR fraction of V in the surface sediments of the four sampling sites showed that V mainly existed in the residual fraction (88.04-88.57%). The concentrations of DGT-labile V (CDGT-V) were considerably lower than the non-residual fractions (the sum of exchangeable, reducible, and oxidizable fractions) measured by BCR sequential extraction. Correlation analysis showed that CDGT-V had no correlation with non-residual V fractions, indicating that it is doubtful whether BCR extraction alone can be used to predict the bioavailability of V in this study.

Feature Selection based on Machine Learning in MRIs for Hippocampal Segmentation

NASA Astrophysics Data System (ADS)

Tangaro, Sabina; Amoroso, Nicola; Brescia, Massimo; Cavuoti, Stefano; Chincarini, Andrea; Errico, Rosangela; Paolo, Inglese; Longo, Giuseppe; Maglietta, Rosalia; Tateo, Andrea; Riccio, Giuseppe; Bellotti, Roberto

2015-01-01

Neurodegenerative diseases are frequently associated with structural changes in the brain. Magnetic resonance imaging (MRI) scans can show these variations and therefore can be used as a supportive feature for a number of neurodegenerative diseases. The hippocampus has been known to be a biomarker for Alzheimer disease and other neurological and psychiatric diseases. However, it requires accurate, robust, and reproducible delineation of hippocampal structures. Fully automatic methods are usually the voxel based approach; for each voxel a number of local features were calculated. In this paper, we compared four different techniques for feature selection from a set of 315 features extracted for each voxel: (i) filter method based on the Kolmogorov-Smirnov test; two wrapper methods, respectively, (ii) sequential forward selection and (iii) sequential backward elimination; and (iv) embedded method based on the Random Forest Classifier on a set of 10 T1-weighted brain MRIs and tested on an independent set of 25 subjects. The resulting segmentations were compared with manual reference labelling. By using only 23 feature for each voxel (sequential backward elimination) we obtained comparable state-of-the-art performances with respect to the standard tool FreeSurfer.

Continuous-flow extraction system for elemental association study: a case of synthetic metal-doped iron hydroxide.

PubMed

Hinsin, Duangduean; Pdungsap, Laddawan; Shiowatana, Juwadee

2002-12-06

A continuous-flow extraction system originally developed for sequential extraction was applied to study elemental association of a synthetic metal-doped amorphous iron hydroxide phase. The homogeneity and metal association of the precipitates were evaluated by gradual leaching using the system. Leachate was collected in fractions for determination of elemental concentrations. The result obtained as extractograms indicated that the doped metals were adsorbed more on the outermost surface rather than homogeneously distributed in the precipitates. The continuous-flow extraction method was also used for effective removal of surface adsorbed metals to obtain a homogeneous metal-doped synthetic iron hydroxide by a sequential extraction using acetic acid and small volume of hydroxylamine hydrochloride solution. The system not only ensures complete washing, but the extent of metal immobilization in the synthetic iron hydroxide could be determined with high accuracy from the extractograms. The initial metal/iron mole ratio (M/Fe) in solution affected the M/Fe mole ratio in homogeneous doped iron hydroxide phase. The M/Fe mole ratio of metal incorporation was approximately 0.01-0.02 and 0.03-0.06, for initial solution M/Fe mole ratio of 0.025 and 0.100, respectively.

Intensive glycaemic control for patients with type 2 diabetes: systematic review with meta-analysis and trial sequential analysis of randomised clinical trials

PubMed Central

Lund, Søren S; Gluud, Christian; Vaag, Allan; Almdal, Thomas; Wetterslev, Jørn

2011-01-01

Objective To assess the effect of targeting intensive glycaemic control versus conventional glycaemic control on all cause mortality and cardiovascular mortality, non-fatal myocardial infarction, microvascular complications, and severe hypoglycaemia in patients with type 2 diabetes. Design Systematic review with meta-analyses and trial sequential analyses of randomised trials. Data sources Cochrane Library, Medline, Embase, Science Citation Index Expanded, LILACS, and CINAHL to December 2010; hand search of reference lists and conference proceedings; contacts with authors, relevant pharmaceutical companies, and the US Food and Drug Administration. Study selection Randomised clinical trials comparing targeted intensive glycaemic control with conventional glycaemic control in patients with type 2 diabetes. Published and unpublished trials in all languages were included, irrespective of predefined outcomes. Data extraction Two reviewers independently assessed studies for inclusion and extracted data related to study methods, interventions, outcomes, risk of bias, and adverse events. Risk ratios with 95% confidence intervals were estimated with fixed and random effects models. Results Fourteen clinical trials that randomised 28 614 participants with type 2 diabetes (15 269 to intensive control and 13 345 to conventional control) were included. Intensive glycaemic control did not significantly affect the relative risks of all cause (1.02, 95% confidence interval 0.91 to 1.13; 28 359 participants, 12 trials) or cardiovascular mortality (1.11, 0.92 to 1.35; 28 359 participants, 12 trials). Trial sequential analyses rejected a relative risk reduction above 10% for all cause mortality and showed insufficient data on cardiovascular mortality. The risk of non-fatal myocardial infarction may be reduced (relative risk 0.85, 0.76 to 0.95; P=0.004; 28 111 participants, 8 trials), but this finding was not confirmed in trial sequential analysis. Intensive glycaemic control showed a reduction of the relative risks for the composite microvascular outcome (0.88, 0.79 to 0.97; P=0.01; 25 600 participants, 3 trials) and retinopathy (0.80, 0.67 to 0.94; P=0.009; 10 793 participants, 7 trials), but trial sequential analyses showed that sufficient evidence had not yet been reached. The estimate of an effect on the risk of nephropathy (relative risk 0.83, 0.64 to 1.06; 27 769 participants, 8 trials) was not statistically significant. The risk of severe hypoglycaemia was significantly increased when intensive glycaemic control was targeted (relative risk 2.39, 1.71 to 3.34; 27 844 participants, 9 trials); trial sequential analysis supported a 30% increased relative risk of severe hypoglycaemia. Conclusion Intensive glycaemic control does not seem to reduce all cause mortality in patients with type 2 diabetes. Data available from randomised clinical trials remain insufficient to prove or refute a relative risk reduction for cardiovascular mortality, non-fatal myocardial infarction, composite microvascular complications, or retinopathy at a magnitude of 10%. Intensive glycaemic control increases the relative risk of severe hypoglycaemia by 30%. PMID:22115901

Distribution and uptake dynamics of mercury in leaves of common deciduous tree species in Minnesota, U.S.A.

Treesearch

Aicam Laacouri; Edward A. Nater; Randall K. Kolka

2013-01-01

A sequential extraction technique for compartmentalizing mercury (Hg) in leaves was developed based on a water extraction of Hg from the leaf surface followed by a solvent extraction of the cuticle. The bulk of leaf Hg was found in the tissue compartment (90-96%) with lesser amounts in the surface and cuticle compartments. Total leaf concentrations of Hg varied among...

Erythrocyte antioxidant protection of rose hips (Rosa spp.).

PubMed

Widén, C; Ekholm, A; Coleman, M D; Renvert, S; Rumpunen, K

2012-01-01

Rose hips are popular in health promoting products as the fruits contain high content of bioactive compounds. The aim of this study was to investigate whether health benefits are attributable to ascorbic acid, phenols, or other rose-hip-derived compounds. Freeze-dried powder of rose hips was preextracted with metaphosphoric acid and the sample was then sequentially eluted on a C(18) column. The degree of amelioration of oxidative damage was determined in an erythrocyte in vitro bioassay by comparing the effects of a reducing agent on erythrocytes alone or on erythrocytes pretreated with berry extracts. The maximum protection against oxidative stress, 59.4 ± 4.0% (mean ± standard deviation), was achieved when incubating the cells with the first eluted meta-phosphoric extract. Removal of ascorbic acid from this extract increased the protection against oxidative stress to 67.9 ± 1.9%. The protection from the 20% and 100% methanol extracts was 20.8 ± 8.2% and 5.0 ± 3.2%, respectively. Antioxidant uptake was confirmed by measurement of catechin by HPLC-ESI-MS in the 20% methanol extract. The fact that all sequentially eluted extracts studied contributed to protective effects on the erythrocytes indicates that rose hips contain a promising level of clinically relevant antioxidant protection.

Immobilization of metals in contaminated soils using natural polymer-based stabilizers.

PubMed

Tao, Xue; Li, Aimin; Yang, Hu

2017-03-01

Three low-cost natural polymer materials, namely, lignin (Ln), carboxymethyl cellulose, and sodium alginate, were used for soil amendment to immobilize lead and cadmium in two contaminated soil samples collected from a mining area in Nanjing, China. The remediation effects of the aforementioned natural polymers were evaluated by toxicity characteristic leaching procedure (TCLP) and sequential extractions. The stabilizers could lower the bioavailability of Pb and Cd in the contaminated soils, and the amount of the exchangeable forms of the aforementioned two metals were reduced evidently. TCLP results showed that the leaching concentrations of Pb and Cd were decreased by 5.46%-71.1% and 4.25%-49.6%, respectively, in the treated soils. The contents of the organic forms of the two metals both increased with the increase in stabilizer dose on the basis of the redistribution of metal forms by sequential extractions. These findings were due to the fact that the abundant oxygen-containing groups on the polymeric amendments were effective in chelating and immobilizing Pb and Cd, which have been further confirmed from the metal adsorptions in aqueous solutions. Moreover, Ln achieved the greatest effect among the three polymers under study because of the former's distinct three-dimensional molecular structure, showing the preferential immobilization of Pb over Cd in soils also. Thus, the above-mentioned natural polymers hold great application potentials for reducing metal ion entry into the food chain at a field scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dynamics of metals in backfill of a phosphate mine of guiyang, China using a three-step sequential extraction technique.

PubMed

Shi, Ying; Gan, Lei; Li, Xibing; He, Suya; Sun, Cheng; Gao, Li

2018-02-01

Phosphate rock in Guiyang (Southwest of China) is used for the phosphate production, and hence generating a by-product phosphogypsum (PG). From 2007, part of the PG was used as main raw material for cemented backfill. The main objective of this paper is to investigate the geochemical evolution of metals before and after the PG inclusion into the backfill matrix. A sequential extraction procedure was selected to determine the chemical speciation of metals in phosphate rock, PG, binder and field backfill samples. Dynamics of metals going from phosphate rock and PG to backfill have been evaluated. The results showed that almost all the metals in the PG and binder had been effectively transferred to the backfill. Furthermore, compared to metals taken out along with phosphate rock exploitation, PG-based cemented backfill might bring some metals back but with only little metals in mobile fraction. Additionally, in order to determine the long-term behavior of metals in PG-based cemented backfill, the field samples which were backfilled from 2007 to 2016 were collected and analyzed. The results showed that total amounts of metals in backfill were all within similar range, indicating that the cemented PG backfill could be an effective method to solidify/stabilize metals in PG. Nevertheless, Due to the high water-soluble fractions detected, the concentrations of As, Mn and Zn should be continuously monitored. Copyright © 2017. Published by Elsevier Ltd.

Split Flow Online Solid-Phase Extraction Coupled with Inductively Coupled Plasma Mass Spectrometry System for One-Shot Data Acquisition of Quantification and Recovery Efficiency.

PubMed

Furukawa, Makoto; Takagai, Yoshitaka

2016-10-04

Online solid-phase extraction (SPE) coupled with inductively coupled plasma mass spectrometry (ICPMS) is a useful tool in automatic sequential analysis. However, it cannot simultaneously quantify the analytical targets and their recovery percentages (R%) in one-shot samples. We propose a system that simultaneously acquires both data in a single sample injection. The main flowline of the online solid-phase extraction is divided into main and split flows. The split flow line (i.e., bypass line), which circumvents the SPE column, was placed on the main flow line. Under program-controlled switching of the automatic valve, the ICPMS sequentially measures the targets in a sample before and after column preconcentration and determines the target concentrations and the R% on the SPE column. This paper describes the system development and two demonstrations to exhibit the analytical significance, i.e., the ultratrace amounts of radioactive strontium ( 90 Sr) using commercial Sr-trap resin and multielement adsorbability on the SPE column. This system is applicable to other flow analyses and detectors in online solid phase extraction.

Extraction of rare earth elements from a contaminated cropland soil using nitric acid, citric acid, and EDTA.

PubMed

Tang, Hailong; Shuai, Weitao; Wang, Xiaojing; Liu, Yangsheng

2017-08-01

Rare earth elements (REEs) contamination to the surrounding soil has increased the concerns of health risk to the local residents. Soil washing was first attempted in our study to remediate REEs-contaminated cropland soil using nitric acid, citric acid, and ethylene diamine tetraacetic acid (EDTA) for soil decontamination and possible recovery of REEs. The extraction time, washing agent concentration, and pH value of the washing solution were optimized. The sequential extraction analysis proposed by Tessier was adopted to study the speciation changes of the REEs before and after soil washing. The extract containing citric acid was dried to obtain solid for the X-ray fluorescence (XRF) analysis. The results revealed that the optimal extraction time was 72 h, and the REEs extraction efficiency increased as the agent concentration increased from 0.01 to 0.1 mol/L. EDTA was efficient to extract REEs over a wide range of pH values, while citric acid was around pH 6.0. Under optimized conditions, the average extraction efficiencies of the major REEs in the contaminated soil were 70.96%, 64.38%, and 62.12% by EDTA, nitric acid, and citric acid, respectively. The sequential extraction analyses revealed that most soil-bounded REEs were mobilized or extracted except for those in the residual fraction. Under a comprehensive consideration of the extraction efficiency and the environmental impact, citric acid was recommended as the most suitable agent for extraction of the REEs from the contaminated cropland soils. The XRF analysis revealed that Mn, Al, Si, Pb, Fe, and REEs were the major elements in the extract indicating a possibile recovery of the REEs.

Sequential healing at implants installed immediately into extraction sockets. An experimental study in dogs.

PubMed

Mainetti, Tomaso; Lang, Niklaus P; Bengazi, Franco; Favero, Vittorio; Soto Cantero, Luis; Botticelli, Daniele

2016-01-01

To compare the sequential healing at implants installed in a healed alveolar bony ridge or immediately after tooth extraction without functional load. In the mandible of 12 dogs, the mesial roots of the first molars were endodontically treated, the tooth hemisected, and the distal roots extracted. After 3 months, the mesial roots of the fourth premolars were endodontically treated, the tooth hemisected, and the distal roots extracted in one side of the mandible. Implants were placed immediately into extraction sockets (IPIES) of the fourth premolar and in the healed sites in the molar regions. Healing abutments were placed, and the flaps were sutured to allow a non-submerged healing. The time of surgery and of sacrifices were planned in such a way to obtain biopsies representing the healing after 1 and 2 weeks and 1 and 3 months, respectively. Ground sections were prepared for histological evaluation of tissues components on the implant surface and the coronal termination level of osseointegration (M-B). New bone apposition on the implant surface was slightly higher at the healed compared to the IPIES sites, being 7.4% and 4.1% after 1 week, and 67.3% and 65.3% after 3 months, respectively. Old bone was progressively resorbed, from 27.0% and 21.9% after 1 week, to 2.5% and 2.0% after 3 months, at healed and IPIES sites, respectively. M-B was 1.4 mm and 2.6 mm after 1 week, 1.2 mm and 1.2 mm after 3 months, at healed and IPIES sites, respectively. Similar patterns of sequential osseointegration were found at implants installed in healed alveolar bone or in alveolar sockets immediately after tooth extraction. The coronal termination level of osseointegration, that was different after 1 week, was found similar at the 3-month observation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effect Of Soil Properties On The Geochemical Speciation Of Arsenic In Contaminated Soils: A Greenhouse Study

NASA Astrophysics Data System (ADS)

Sharma, S.; Sarkar, D.; Datta, R.

2005-05-01

Land-applied arsenical pesticides have contributed elevated soil arsenic (As) levels. Many baseline risk assessments As-contaminated sites assume that all As present in the soil is bioavailable, thereby potentially overestimating the actual health risk. However, risk from As exposure is associated only with those forms of As that are potentially extractable by the human gastrointestinal juices. It has been demonstrated that As may exist in several geochemical forms depending on soil chemical properties, which may or may not be bioavailable. The current study aims at addressing the issue of soil variability on As bioavailability as a function of soil physico-chemical properties in a greenhouse setting involving dynamic interactions between soil, water and plants. Four different soils were chosen based on their potential differences with respect to As reactivity: Immokalee, an acid sand with low extractable Fe/Al, having minimal arsenic retention capacity; Millhopper, an acid sandy loam with high extractable Fe/Al oxides; Pahokee Muck soil with 85% soil organic matter (SOM) as well as high Fe/Al content; and Orelia soil with high clay and Fe/Al content. Soils were amended with sodium arsenate (675 and 1500 mg/Kg). Rice (Oryza sativa) was used as the test crop. A sequential extraction scheme was employed to identify the geochemical forms of As in soils (soluble, exchangeable, organic, Fe/Al-bound, Ca/Mg-bound, residual) immediately after spiking; after 3 mo; and after 6 mo of equilibration time. Concentrations of these As forms were correlated with the in-vitro bioavailable As fractions to identify those As fractions that are most likely to be bioavailable. Results from this study showed that there was little to no plant growth in the contaminated soils. Sequential extractions of the soil indicated that arsenic is strongly adsorbed onto soil amorphous iron/aluminum oxides, and the degree of arsenic retention is a direct function of equilibration time.

Mining local climate data to assess spatiotemporal dengue fever epidemic patterns in French Guiana

PubMed Central

Flamand, Claude; Fabregue, Mickael; Bringay, Sandra; Ardillon, Vanessa; Quénel, Philippe; Desenclos, Jean-Claude; Teisseire, Maguelonne

2014-01-01

Objective To identify local meteorological drivers of dengue fever in French Guiana, we applied an original data mining method to the available epidemiological and climatic data. Through this work, we also assessed the contribution of the data mining method to the understanding of factors associated with the dissemination of infectious diseases and their spatiotemporal spread. Methods We applied contextual sequential pattern extraction techniques to epidemiological and meteorological data to identify the most significant climatic factors for dengue fever, and we investigated the relevance of the extracted patterns for the early warning of dengue outbreaks in French Guiana. Results The maximum temperature, minimum relative humidity, global brilliance, and cumulative rainfall were identified as determinants of dengue outbreaks, and the precise intervals of their values and variations were quantified according to the epidemiologic context. The strongest significant correlations were observed between dengue incidence and meteorological drivers after a 4–6-week lag. Discussion We demonstrated the use of contextual sequential patterns to better understand the determinants of the spatiotemporal spread of dengue fever in French Guiana. Future work should integrate additional variables and explore the notion of neighborhood for extracting sequential patterns. Conclusions Dengue fever remains a major public health issue in French Guiana. The development of new methods to identify such specific characteristics becomes crucial in order to better understand and control spatiotemporal transmission. PMID:24549761

Identification and Characterization of Cell Wall Proteins of a Toxic Dinoflagellate Alexandrium catenella Using 2-D DIGE and MALDI TOF-TOF Mass Spectrometry

PubMed Central

Wang, Da-Zhi; Dong, Hong-Po; Li, Cheng; Xie, Zhang-Xian; Lin, Lin; Hong, Hua-Sheng

2011-01-01

The cell wall is an important subcellular component of dinoflagellate cells with regard to various aspects of cell surface-associated ecophysiology, but the full range of cell wall proteins (CWPs) and their functions remain to be elucidated. This study identified and characterized CWPs of a toxic dinoflagellate, Alexandrium catenella, using a combination of 2D fluorescence difference gel electrophoresis (DIGE) and MALDI TOF-TOF mass spectrometry approaches. Using sequential extraction and temperature shock methods, sequentially extracted CWPs and protoplast proteins, respectively, were separated from A. catenella. From the comparison between sequentially extracted CWPs labeled with Cy3 and protoplast proteins labeled with Cy5, 120 CWPs were confidently identified in the 2D DIGE gel. These proteins gave positive identification of protein orthologues in the protein database using de novo sequence analysis and homology-based search. The majority of the prominent CWPs identified were hypothetical or putative proteins with unknown function or no annotation, while cell wall modification enzymes, cell wall structural proteins, transporter/binding proteins, and signaling and defense proteins were tentatively identified in agreement with the expected role of the extracellular matrix in cell physiology. This work represents the first attempt to investigate dinoflagellate CWPs and provides a potential tool for future comprehensive characterization of dinoflagellate CWPs and elucidation of their physiological functions. PMID:21904561

Evaluation of the antiproliferative activity of the leaves from Arctium lappa by a bioassay-guided fractionation.

PubMed

Machado, Fabio Bahls; Yamamoto, Rafael Eidi; Zanoli, Karine; Nocchi, Samara Requena; Novello, Cláudio Roberto; Schuquel, Ivânia Teresinha Albrecht; Sakuragui, Cássia Mônica; Luftmann, Heinrich; Ueda-Nakamura, Tânia; Nakamura, Celso Vataru; de Mello, João Carlos Palazzo

2012-02-14

Arctium lappa L. (Asteraceae) is used in folk medicine around the World, and shows several kinds of biological activity, particularly in vitro antitumor activity in different cell lines. This study evaluated the antiproliferative activity of the crude extract, semipurified fractions, and isolated compounds from the leaves of A. lappa, through bioassay-guided testing in Caco-2 cells. The crude extract was obtained with a 50% hydroethanolic extract and then partitioned with hexane, ethyl acetate, and n-butanol. The ethyl-acetate fraction (EAF) showed antiproliferative activity. This fraction was subjected to sequential column chromatography over silica gel to afford onopordopicrin (1), mixtures of 1 with dehydromelitensin-8-(4'-hydroxymethacrylate) (2), a mixture of 2 with dehydromelitensin (3), mixture of 1 with melitensin (4), dehydrovomifoliol (5), and loliolide (6). The compounds were identified by spectroscopic methods (NMR, MS) and comparison with literature data. This is the first description of compounds 2-5 from this species. The compounds tested in Caco-2 cells showed the following CC(50) (µg/mL) values: 1: 19.7 ± 3.4, 1 with 2: 24.6 ± 1.5, 2 with 3: 27 ± 11.7, 1 with 4: 42 ± 13.1, 6 30 ± 6.2; compound 5 showed no activity.

Sequentially reweighted TV minimization for CT metal artifact reduction.

PubMed

Zhang, Xiaomeng; Xing, Lei

2013-07-01

Metal artifact reduction has long been an important topic in x-ray CT image reconstruction. In this work, the authors propose an iterative method that sequentially minimizes a reweighted total variation (TV) of the image and produces substantially artifact-reduced reconstructions. A sequentially reweighted TV minimization algorithm is proposed to fully exploit the sparseness of image gradients (IG). The authors first formulate a constrained optimization model that minimizes a weighted TV of the image, subject to the constraint that the estimated projection data are within a specified tolerance of the available projection measurements, with image non-negativity enforced. The authors then solve a sequence of weighted TV minimization problems where weights used for the next iteration are computed from the current solution. Using the complete projection data, the algorithm first reconstructs an image from which a binary metal image can be extracted. Forward projection of the binary image identifies metal traces in the projection space. The metal-free background image is then reconstructed from the metal-trace-excluded projection data by employing a different set of weights. Each minimization problem is solved using a gradient method that alternates projection-onto-convex-sets and steepest descent. A series of simulation and experimental studies are performed to evaluate the proposed approach. Our study shows that the sequentially reweighted scheme, by altering a single parameter in the weighting function, flexibly controls the sparsity of the IG and reconstructs artifacts-free images in a two-stage process. It successfully produces images with significantly reduced streak artifacts, suppressed noise and well-preserved contrast and edge properties. The sequentially reweighed TV minimization provides a systematic approach for suppressing CT metal artifacts. The technique can also be generalized to other "missing data" problems in CT image reconstruction.

Information Management: Publishing and Printing: Army Publishing: Action Officers Guide

DTIC Science & Technology

2002-04-30

types of lists: ordered (such as numerical, alphabetical, or sequential ), bulleted, or dashed. (4) Extracted material in an appendix must be identified...provide supporting, expanded, or sequential doctrinal manuals within a functional field (this number group must not exceed 3 digits). Table 13–2...rubup, opaquing, lineup , and register, and so forth 1,2 190 DA PAM 25–40 • 30 April 2002 Table J–5 Camera, platemaking, and related equipment—Continued

Purification and characterization of allergens from Xanthium strumarium pollen.

PubMed

Jaggi, K S; Gangal, S V

1987-12-01

The allergenic components present in whole pollen extract of Xanthium strumarium were isolated by sequential ammonium sulphate precipitation, DEAE Sephadex A50 chromatography and gel filtration. The techniques of RAST inhibition and skin test were utilized to check the allergenicity of fractionated proteins revealing the presence of Xan Ib and Xan VIa as the important allergenic components. Xan Ib was found to be devoid of carbohydrate and had a molecular weight of 103,000 daltons. Xan VIa was a glycoprotein of molecular weight 17,000 daltons. The carbohydrate moiety of Xan VIa was found to be associated with allergenicity. The characteristic pattern of whole pollen extract on CIE and TLIEF showed 36 and 21 protein bands, respectively. The use of FPLC in isolation of partially purified allergens from Xanthium is discussed.

Multi-sensor image registration based on algebraic projective invariants.

PubMed

Li, Bin; Wang, Wei; Ye, Hao

2013-04-22

A new automatic feature-based registration algorithm is presented for multi-sensor images with projective deformation. Contours are firstly extracted from both reference and sensed images as basic features in the proposed method. Since it is difficult to design a projective-invariant descriptor from the contour information directly, a new feature named Five Sequential Corners (FSC) is constructed based on the corners detected from the extracted contours. By introducing algebraic projective invariants, we design a descriptor for each FSC that is ensured to be robust against projective deformation. Further, no gray scale related information is required in calculating the descriptor, thus it is also robust against the gray scale discrepancy between the multi-sensor image pairs. Experimental results utilizing real image pairs are presented to show the merits of the proposed registration method.

Macroalgae Extracts From Antarctica Have Antimicrobial and Anticancer Potential

PubMed Central

Martins, Rosiane M.; Nedel, Fernanda; Guimarães, Victoria B. S.; da Silva, Adriana F.; Colepicolo, Pio; de Pereira, Claudio M. P.; Lund, Rafael G.

2018-01-01

Background: Macroalgae are sources of bioactive compounds due to the large number of secondary metabolites they synthesize. The Antarctica region is characterized by extreme weather conditions and abundant aggregations of macroalgae. However, current knowledge on their biodiversity and their potential for bio-prospecting is still fledging. This study evaluates the antimicrobial and cytotoxic activity of different extracts of four macroalgae (Cystosphaera jacquinotii, Iridaea cordata, Himantothallus grandifolius, and Pyropia endiviifolia) from the Antarctic region against cancer and non-cancer cell lines. Methods: The antimicrobial activity of macroalgae was evaluated by the broth microdilution method. Extracts were assessed against Staphylococcus aureus ATCC 19095, Enterococcus faecalis ATCC 4083, Escherichia coli ATCC29214, Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 62342, and the clinical isolates from the human oral cavity, namely, C. albicans (3), C. parapsilosis, C. glabrata, C. lipolytica, and C. famata. Cytotoxicity against human epidermoid carcinoma (A-431) and mouse embryonic fibroblast (NIH/3T3) cell lines was evaluated with MTT colorimetric assay. Results: An ethyl acetate extract of H. grandifolius showed noticeable antifungal activity against all fungal strains tested, including fluconazole-resistant samples. Cytotoxicity investigation with a cancer cell line revealed that the ethyl acetate extract of I. cordata was highly cytotoxic against A-431 cancer cell line, increasing the inhibitory ratio to 91.1 and 95.6% after 24 and 48 h exposure, respectively, for a concentration of 500 μg mL−1. Most of the algal extracts tested showed little or no cytotoxicity against fibroblasts. Conclusion: Data suggest that macroalgae extracts from Antarctica may represent a source of therapeutic agents. HIGHLIGHTS Different macroalgae samples from Antarctica were collected and the lyophilized biomass of each macroalgae was extracted sequentially with different solventsThe antimicrobial and anticancer potential of macroalgae extracts were evaluatedEthyl acetate extract of H. grandifolius showed noticeable antifungal activity against all the fungal strains tested, including fluconazole-resistant samplesEthyl acetate extract of I. cordata was highly cytotoxic against the A-431 cancer cell lineMost of the algal extracts tested showed little or no cytotoxicity against normal cell lines PMID:29568291

Determination and partitioning of metals in sediments along the Suez Canal by sequential extraction

NASA Astrophysics Data System (ADS)

Abd El-Azim, H.; El-Moselhy, Kh. M.

2005-06-01

The application of sequential extraction technique was used to determine the chemical association of heavy metals in five different chemical phases (exchangeable F1, bound to carbonate F2, bound to Fe-Mn oxides F3, bound to organic matter F4 and residual F5) for sediment samples collected from the Suez Canal. From the obtained data, it can be seen that the surplus of metal contaminants introduced into the sediment from sources usually exists in relatively unstable chemical forms. A high proportion of the studied metals remained in the residual fraction. Most of remaining portion of metals was bound to ferromanganese oxides fraction. The low concentrations of metals in the exchangeable fraction indicated that the sediments of Suez Canal were relatively unpolluted.

Characterization of yam bean (Pachyrhizus erosus) proteins.

PubMed

Morales-Arellano, G Y; Chagolla-López, A; Paredes-López, O; Barba de la Rosa, A P

2001-03-01

Seed proteins from Mexican yam bean seeds (Pachyrhizus erosus L.) were sequentially extracted according to the Osborne classification. Albumins were the major fraction (52.1-31.0%), followed by globulins (30.7-27.5%). The minor protein fraction was prolamins (0.8%). Defatting with chloroform/methanol remarkably affected the distribution of protein solubility classes; albumins were the most affected fraction (4.3-17.5%). Electrophoretic patterns of albumins showed bands at 55, 40, 35, and 31 kDa. After reduction of the globulin fraction exhibited two triplets, one from 35 to 31 kDa and the second from 19 to 21 kDa, these could be compared to the acid and basic polypeptides of 11S-like proteins. Prolamins showed one band at 31 kDa, and glutelins after reduction showed three main bands at 52, 27, and 14 kDa. Trypsin inhibitors were assayed in saline extracts; the values found (1232-2608 IU/g of meal) were lower than those of other legumes. In general, yam bean seed proteins showed an excellent balance of all essential amino acids; albumins contain the highest amount of essential amino acids.

Modifications of Saccharomyces pastorianus cell wall polysaccharides with brewing process.

PubMed

Bastos, Rita; Coelho, Elisabete; Coimbra, Manuel A

2015-06-25

The cell wall polysaccharides of brewers spent yeast Saccharomyces pastorianus (BSY) and the inoculum yeast (IY) were studied in order to understand the changes induced by the brewing process. The hot water and alkali extractions performed solubilized mainly mannoproteins, more branched for BSY than those of IY. Also, (31)P solid state NMR showed that the BSY mannoproteins were 3 times more phosphorylated. By electron microscopy it was observed that the final residues of alkali sequential extraction until 4M KOH preserved the yeast three-dimensional structure. The final residues, composed mainly by glucans (92%), showed that the BSY, when compared with IY, contained higher amount of (1→4)-linked Glc (43% for BSY and 16% for IY) and lower (1→3)-linked Glc (17% for BSY and 42% for IY). The enzymatic treatment of final residue showed that both BSY and IY had (α1→4)-linked Glc and (β1→4)-linked Glc, in a 2:1 ratio, showing that S. pastorianus increases their cellulose-like linkages with the brewing process. Copyright © 2015 Elsevier Ltd. All rights reserved.

Utilization of optimized BCR three-step sequential and dilute HCl single extraction procedures for soil-plant metal transfer predictions in contaminated lands.

PubMed

Kubová, Jana; Matús, Peter; Bujdos, Marek; Hagarová, Ingrid; Medved', Ján

2008-05-30

The prediction of soil metal phytoavailability using the chemical extractions is a conventional approach routinely used in soil testing. The adequacy of such soil tests for this purpose is commonly assessed through a comparison of extraction results with metal contents in relevant plants. In this work, the fractions of selected risk metals (Al, As, Cd, Cu, Fe, Mn, Ni, Pb, Zn) that can be taken up by various plants were obtained by optimized BCR (Community Bureau of Reference) three-step sequential extraction procedure (SEP) and by single 0.5 mol L(-1) HCl extraction. These procedures were validated using five soil and sediment reference materials (SRM 2710, SRM 2711, CRM 483, CRM 701, SRM RTH 912) and applied to significantly different acidified soils for the fractionation of studied metals. The new indicative values of Al, Cd, Cu, Fe, Mn, P, Pb and Zn fractional concentrations for these reference materials were obtained by the dilute HCl single extraction. The influence of various soil genesis, content of essential elements (Ca, Mg, K, P) and different anthropogenic sources of acidification on extraction yields of individual risk metal fractions was investigated. The concentrations of studied elements were determined by atomic spectrometry methods (flame, graphite furnace and hydride generation atomic absorption spectrometry and inductively coupled plasma optical emission spectrometry). It can be concluded that the data of extraction yields from first BCR SEP acid extractable step and soil-plant transfer coefficients can be applied to the prediction of qualitative mobility of selected risk metals in different soil systems.

Isolation of quercetin from the methanolic extract of Lagerstroemia speciosa by HPLC technique, its cytotoxicity against MCF-7 cells and photocatalytic activity.

PubMed

Sai Saraswathi, V; Saravanan, D; Santhakumar, K

2017-06-01

The flavonoids present in the leaves of Lagerstroemia speciosa were extracted, characterized by spectral methods and studied for its cytotoxicity activity against MCF-cell lines and photocatalytic activity against azo dye. Direct and sequential soxhlet extraction was performed and its concentrated crude extract was subjected to high performance liquid chromatography. The yield obtained by the isolated compound (MEI-quercetin) from leaves of L. speciosa was found to be 1.8g from the methanolic extract. The phytochemical analysis and the Rf value of the isolated flavonoid was found to be 3.59. The isolated compound was characterized by Infrared Spectroscopy, NMR and Mass. Based on the characterization, the structure was elucidated as quercetin - a flavonoid. The isolated compound showed the significant in vitro cytotoxicity activity against MCF-7 cell lines at 500μg/ml when compared to the crude extract. Among the various concentrations (25, 50, 100, 250, and 500μg/ml), at higher concentration the cell viability was pronounced and also compared with that of the control. It was first time to report that the isolated flavonoid showed photocatalytic against azo dye-methyl orange. The dye degradation was monitored by UV-Vis spectrophotometry. The isolated compound showed dye degradation of 91.66% with the crude extract 82.47% at 160min. Hence in the present findings, the photocatalytic degradation of MO dye under UV irradiation was investigated over isolated compound of L. speciosa. Hence we expect that this can be used to treat the waste water in near future based on the photocatalytic technique. Copyright © 2017 Elsevier B.V. All rights reserved.

Estimating bioaccessibility of trace elements in particles suspended in the Athabasca River using sequential extraction.

PubMed

Javed, Muhammad Babar; Shotyk, William

2018-05-10

Employing protocols developed for polar snow and ice, water samples were collected upstream, midstream and downstream of open pit bitumen mines and upgraders along the Lower Athabasca River (AR). The purpose was to: i) estimate the bioaccessibility of trace elements associated with particulate matter in the AR using sequential extraction, and ii) determine whether their forms have been measurably impacted by industrial activities. Of the trace metals known to be enriched in bitumen (V, Ni, Mo and Re), a substantial proportion of V (78-93%) and Ni (35-81%) was found in the residual fraction representing stable minerals. In contrast, Mo and Re were partitioned mainly into more reactive forms (water soluble, acid extractable, reducible and oxidisable). Comparing the non-residual fractions in upstream versus downstream sites, only water soluble Re was significantly (P = 0.005) greater downstream of industry. In respect to the potentially toxic chalcophile elements (Cu, Pb and Tl), no measurable change was observed in Cu and Pb distribution in upstream versus downstream sites. Only residual Tl was found at upstream and midstream sites, whereas a significant proportion of Tl was also present in the reducible fraction in downstream sites. Overall, a greater proportion of trace metals in the residual fraction at midstream sites appears to be due to inputs of atmospheric dust, clearly evident in microscopic images: energy dispersive spectroscopy and x-ray diffraction analyses showed that these particles were predominantly silicates, which are assumed to have limited bioaccessibility. Copyright © 2018 Elsevier Ltd. All rights reserved.

Determination of dextromethorphan in human plasma using pipette tip solid-phase extraction and gas chromatography-mass spectrometry.

PubMed

Hasegawa, Chika; Kumazawa, Takeshi; Uchigasaki, Seisaku; Lee, Xiao-Pen; Sato, Keizo; Terada, Masaru; Kurosaki, Kunihiko

2011-10-01

Dextromethorphan was extracted from human plasma samples (100 μL) using MonoTip C(18) tips, which are packed with C(18)-bonded monolithic silica gel that is attached to the inside of the tip. The samples, which contained dextromethorphan and trimeprazine as an internal standard (IS), were mixed with 200 μL of distilled water and 50 μL of 1 mol/L glycine-sodium hydroxide buffer (pH 10). The mixture was extracted to the C(18) phase of the tip by 20 sequential aspirating/dispensing cycles using a manual micropipettor. The analytes retained on the C(18) phase were then eluted with methanol by five sequential aspirating/dispensing cycles. The eluate was injected directly into a gas chromatograph and detected by a mass spectrometer with selected ion monitoring in positive electron ionization mode. An Equity-5 fused silica capillary column (30 m × 0.32 mm i.d., film thickness 0.5 μm) gave adequate separation of the dextromethorphan, IS, and impurities. The recoveries of dextromethorphan and the IS spiked into plasma were >87.4%. The regression equation for dextromethorphan showed excellent linearity from 2.5 to 320 ng/mL of plasma, and the limit of detection was 1.25 ng/mL of plasma. The intraday and interday coefficients of variation were less than 10.5% and 14.7%, respectively. The accuracy ranged from 91.9% to 107%. The validated method was successfully used to quantify the plasma concentration of dextromethorphan in a human subject after oral administration of the drug. © Springer-Verlag 2011

Two new xanthones from Calophyllum nodusum (Guttiferae).

PubMed

Nasir, Nadiah Mad; Rahmani, Mawardi; Shaari, Khozirah; Ee, Gwendoline Cheng Lian; Go, Rusea; Kassim, Nur Kartinee; Muhamad, Siti Noor Kamilah; Iskandar, Mohd Johadi

2011-10-25

The air-dried powdered stem bark of Calophyllum nodusum (Guttiferea) collected from Sandakan (Sabah, Malaysia), was extracted sequentially with hexane, chloroform and methanol. The solvents were removed by rotary evaporator to give dark viscous extracts. Detailed and repeated chromatographic separation of the extracts lead to isolation of two new xanthones, identified as nodusuxanthone and trapezifolixanthone A. Other common terpenoids such as betulinic acid, lupeol, stigmasterol and friedelin were also isolated from the extracts and identified. The structures of the compounds were established by detailed spectral analysis and comparison with previously reported data.

Direct Estimation of Structure and Motion from Multiple Frames

DTIC Science & Technology

1990-03-01

sequential frames in an image sequence. As a consequence, the information that can be extracted from a single optical flow field is limited to a snapshot of...researchers have developed techniques that extract motion and structure inform.4tion without computation of the optical flow. Best known are the "direct...operated iteratively on a sequence of images to recover structure. It required feature extraction and matching. Broida and Chellappa [9] suggested the use of

Sequentially Integrated Optimization of the Conditions to Obtain a High-Protein and Low-Antinutritional Factors Protein Isolate from Edible Jatropha curcas Seed Cake.

PubMed

León-López, Liliana; Dávila-Ortiz, Gloria; Jiménez-Martínez, Cristian; Hernández-Sánchez, Humberto

2013-01-01

Jatropha curcas seed cake is a protein-rich byproduct of oil extraction which could be used to produce protein isolates. The purpose of this study was the optimization of the protein isolation process from the seed cake of an edible provenance of J. curcas by an alkaline extraction followed by isoelectric precipitation method via a sequentially integrated optimization approach. The influence of four different factors (solubilization pH, extraction temperature, NaCl addition, and precipitation pH) on the protein and antinutritional compounds content of the isolate was evaluated. The estimated optimal conditions were an extraction temperature of 20°C, a precipitation pH of 4, and an amount of NaCl in the extraction solution of 0.6 M for a predicted protein content of 93.3%. Under these conditions, it was possible to obtain experimentally a protein isolate with 93.21% of proteins, 316.5 mg 100 g(-1) of total phenolics, 2891.84 mg 100 g(-1) of phytates and 168 mg 100 g(-1) of saponins. The protein content of the this isolate was higher than the content reported by other authors.

Sequentially Integrated Optimization of the Conditions to Obtain a High-Protein and Low-Antinutritional Factors Protein Isolate from Edible Jatropha curcas Seed Cake

PubMed Central

León-López, Liliana; Dávila-Ortiz, Gloria; Jiménez-Martínez, Cristian; Hernández-Sánchez, Humberto

2013-01-01

Jatropha curcas seed cake is a protein-rich byproduct of oil extraction which could be used to produce protein isolates. The purpose of this study was the optimization of the protein isolation process from the seed cake of an edible provenance of J. curcas by an alkaline extraction followed by isoelectric precipitation method via a sequentially integrated optimization approach. The influence of four different factors (solubilization pH, extraction temperature, NaCl addition, and precipitation pH) on the protein and antinutritional compounds content of the isolate was evaluated. The estimated optimal conditions were an extraction temperature of 20°C, a precipitation pH of 4, and an amount of NaCl in the extraction solution of 0.6 M for a predicted protein content of 93.3%. Under these conditions, it was possible to obtain experimentally a protein isolate with 93.21% of proteins, 316.5 mg 100 g−1 of total phenolics, 2891.84 mg 100 g−1 of phytates and 168 mg 100 g−1 of saponins. The protein content of the this isolate was higher than the content reported by other authors. PMID:25937971

Sequential protein extraction as an efficient method for improved proteome coverage in larvae of Atlantic salmon (Salmo salar).

PubMed

Nuez-Ortín, Waldo G; Carter, Chris G; Nichols, Peter D; Wilson, Richard

2016-07-01

Understanding diet- and environmentally induced physiological changes in fish larvae is a major goal for the aquaculture industry. Proteomic analysis of whole fish larvae comprising multiple tissues offers considerable potential but is challenging due to the very large dynamic range of protein abundance. To extend the coverage of the larval phase of the Atlantic salmon (Salmo salar) proteome, we applied a two-step sequential extraction (SE) method, based on differential protein solubility, using a nondenaturing buffer containing 150 mM NaCl followed by a denaturing buffer containing 7 M urea and 2 M thiourea. Extracts prepared using SE and one-step direct extraction were characterized via label-free shotgun proteomics using nanoLC-MS/MS (LTQ-Orbitrap). SE partitioned the proteins into two fractions of approximately equal amounts, but with very distinct protein composition, leading to identification of ∼40% more proteins than direct extraction. This fractionation strategy enabled the most detailed characterization of the salmon larval proteome to date and provides a platform for greater understanding of physiological changes in whole fish larvae. The MS data are available via the ProteomeXchange Consortium PRIDE partner repository, dataset PXD003366. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sequential cloud-point extraction for toxicological screening analysis of medicaments in human plasma by high pressure liquid chromatography with diode array detector.

PubMed

Madej, Katarzyna; Persona, Karolina; Wandas, Monika; Gomółka, Ewa

2013-10-18

A complex extraction system with the use of cloud-point extraction technique (CPE) was developed for sequential isolation of basic and acidic/neutral medicaments from human plasma/serum, screened by HPLC/DAD method. Eight model drugs (paracetamol, promazine, chlorpromazine, amitriptyline, salicyclic acid, opipramol, alprazolam and carbamazepine) were chosen for the study of optimal CPE conditions. The CPE technique consists in partition of an aqueous sample with addition of a surfactant into two phases: micelle-rich phase with the isolated compounds and water phase containing a surfactant below the critical micellar concentration, mainly under influence of temperature change. The proposed extraction system consists of two chief steps: isolation of basic compounds (from pH 12) and then isolation of acidic/neutral compounds (from pH 6) using surfactant Triton X-114 as the extraction medium. Extraction recovery varied from 25.2 to 107.9% with intra-day and inter-day precision (RSD %) ranged 0.88-1087 and 5.32-17.96, respectively. The limits of detection for the studied medicaments at λ 254nm corresponded to therapeutic or low toxic plasma concentration levels. Usefulness of the proposed CPE-HPLC/DAD method for toxicological drug screening was tested via its application to analysis of two serum samples taken from patients suspected of drug overdosing. Published by Elsevier B.V.

A stacked sequential learning method for investigator name recognition from web-based medical articles

NASA Astrophysics Data System (ADS)

Zhang, Xiaoli; Zou, Jie; Le, Daniel X.; Thoma, George

2010-01-01

"Investigator Names" is a newly required field in MEDLINE citations. It consists of personal names listed as members of corporate organizations in an article. Extracting investigator names automatically is necessary because of the increasing volume of articles reporting collaborative biomedical research in which a large number of investigators participate. In this paper, we present an SVM-based stacked sequential learning method in a novel application - recognizing named entities such as the first and last names of investigators from online medical journal articles. Stacked sequential learning is a meta-learning algorithm which can boost any base learner. It exploits contextual information by adding the predicted labels of the surrounding tokens as features. We apply this method to tag words in text paragraphs containing investigator names, and demonstrate that stacked sequential learning improves the performance of a nonsequential base learner such as an SVM classifier.

Effect of bamboo and rice straw biochars on the mobility and redistribution of heavy metals (Cd, Cu, Pb and Zn) in contaminated soil.

PubMed

Lu, Kouping; Yang, Xing; Gielen, Gerty; Bolan, Nanthi; Ok, Yong Sik; Niazi, Nabeel Khan; Xu, Song; Yuan, Guodong; Chen, Xin; Zhang, Xiaokai; Liu, Dan; Song, Zhaoliang; Liu, Xingyuan; Wang, Hailong

2017-01-15

Biochar has emerged as an efficient tool to affect bioavailability of heavy metals in contaminated soils. Although partially understood, a carefully designed incubation experiment was performed to examine the effect of biochar on mobility and redistribution of Cd, Cu, Pb and Zn in a sandy loam soil collected from the surroundings of a copper smelter. Bamboo and rice straw biochars with different mesh sizes (<0.25 mm and <1 mm), were applied at three rates (0, 1, and 5% w/w). Heavy metal concentrations in pore water were determined after extraction with 0.01 M CaCl 2 . Phytoavailable metals were extracted using DTPA/TEA (pH 7.3). The European Union Bureau of Reference (EUBCR) sequential extraction procedure was adopted to determine metal partitioning and redistribution of heavy metals. Results showed that CaCl 2 -and DTPA-extractable Cd, Cu, Pb and Zn concentrations were significantly (p < 0.05) lower in the bamboo and rice straw biochar treated soils, especially at 5% application rate, than those in the unamended soil. Soil pH values were significantly correlated with CaCl 2 -extractable metal concentrations (p < 0.01). The EUBCR sequential extraction procedure revealed that the acid extractable fractions of Cd, Cu, Pb and Zn decreased significantly (p < 0.05) with biochar addition. Rice straw biochar was more effective than bamboo biochar in decreasing the acid extractable metal fractions, and the effect was more pronounced with increasing biochar application rate. The effect of biochar particle size on extractable metal concentrations was not consistent. The 5% rice straw biochar treatment reduced the DTPA-extractable metal concentrations in the order of Cd < Cu < Pb < Zn, and reduced the acid extractable pool of Cd, Cu, Pb and Zn by 11, 17, 34 and 6%, respectively, compared to the control. In the same 5% rice straw biochar treatments, the organic bound fraction increased by 37, 58, 68 and 18% for Cd, Cu, Pb and Zn, respectively, compared to the control, indicating that the immobilized metals were mainly bound in the soil organic matter fraction. The results demonstrated that the rice straw biochar can effectively immobilize heavy metals, thereby reducing their mobility and bioavailability in contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electron microscopic observations of mouse sperm whole mounts after extraction for nuclear matrix and intermediate filaments.

PubMed

Markova, M D

2001-01-01

Nuclear matrix and intermediate filaments (NM-IF) can be isolated by sequential treatment with non-ionic detergent, high salt. and nuclease. Extracted cells are easily observed by unembedded whole-mount transmission electron microscopy. Different somatic cell types have been subjected to this procedure and retained their essential architecture. To our knowledge, this work describes the first application of NM-IF extraction to sperm. After chemical dissection the general appearance of mouse sperm cells was preserved, except for head-from-neck separation in some cases. The cell membrane, acrosome and mitochondria were not present. The nucleus showed no apparent changes and revealed no details excepting pore complexes in the posterior part. Tissue-specific cytoskeletal elements (perforatorium, postacrosomal sheath, capitulum, segmented columns, outer dense fibers, submitochondrial reticulum, annulus, and fibrous sheath) were retained, which permitted a parallel between them and intermediate filaments of somatic cells. Tail microtubules were also relatively well preserved, showing high intrinsic stability. Cell structures could be observed well, with some details in the tail even better visible than in ultrathin sections. Observation of mouse sperm whole mounts after NM-IF extraction not only revealed intermediate filament-like properties of their cytoskeletal elements but also offered an additional viewpoint to sperm ultrastructure.

Automobile shredded residue valorisation by hydrometallurgical metal recovery.

PubMed

Granata, Giuseppe; Moscardini, Emanuela; Furlani, Giuliana; Pagnanelli, Francesca; Toro, Luigi

2011-01-15

The aim of this work was developing a hydrometallurgical process to recover metals from automobile shredded residue (or car fluff). Automobile shredded residue (ASR) was characterised by particle size distribution, total metal content and metal speciation in order to guide the choice of target metals and the operating conditions of leaching. Characterisation results showed that Fe is the most abundant metal in the waste, while Zn was the second abundant metal in the fraction with diameter lower than 500 μm. Sequential extractions denoted that Zn was easily extractable by weak acid attack, while Fe and Al required a strong acid attack to be removed. In order to recover zinc from <500 μm fraction leaching tests were operated using acetic acid, sulphuric acid and sodium hydroxide at different concentrations. Sulphuric acid determined the highest zinc extraction yield, while acetic acid determined the highest zinc extractive selectivity. Sodium hydroxide promoted an intermediate situation between sulphuric and acetic acid. Zn recovery by electro winning using acetic leach liquor determined 95% of Zn electro deposition yield in 1h, while using sulphuric leach liquor 40% yield in 1h and 50% yield in 2h were obtained. Simulation results showed that the sulphuric leaching process was more attractive than acetic leaching process. Copyright © 2010 Elsevier B.V. All rights reserved.

Development of a simultaneous multiple solid-phase microextraction-single shot-gas chromatography/mass spectrometry method and application to aroma profile analysis of commercial coffee.

PubMed

Lee, Changgook; Lee, Younghoon; Lee, Jae-Gon; Buglass, Alan J

2013-06-21

A simultaneous multiple solid-phase microextraction-single shot-gas chromatography mass spectrometry (smSPME-ss-GC/MS) method has been developed for headspace analysis. Up to four fibers (50/30 μm DVB/CAR/PDMS) were used simultaneously for the extraction of aroma components from the headspace of a single sample chamber in order to increase sensitivity of aroma extraction. To avoid peak broadening and to maximize resolution, a simple cryofocusing technique was adopted during sequential thermal desorption of multiple SPME fibers prior to a 'single shot' chromatographic run. The method was developed and validated on a model flavor mixture, containing 81 known pure components. With the conditions of 10 min of incubation and 30 min of extraction at 50 °C, single, dual, triple and quadruple SPME extractions were compared. The increase in total peak area with increase in the number of fibers showed good linearity (R(2)=0.9917) and the mean precision was 12.0% (RSD) for the total peak sum, with quadruple simultaneous SPME extraction. Using a real sample such as commercial coffee granules, aroma profile analysis was conducted using single, dual, triple and quadruple SPME fibers. The increase in total peak intensity again showed good linearity with increase in the number of SPME fibers used (R(2)=0.9992) and the precision of quadruple SPME extraction was 9.9% (RSD) for the total peak sum. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of inorganic and organic copper fertilizers on copper nutrition in Spinacia oleracea and on labile copper in soil.

PubMed

Obrador, Ana; Gonzalez, Demetrio; Alvarez, Jose M

2013-05-22

To ensure an optimal concentration of Cu in food crops, the effectiveness of eight liquid Cu fertilizers was studied in a spinach ( Spinacia oleracea L.) crop grown on Cu-deficient soil under greenhouse conditions. Plant dry matter yields, Cu concentrations in spinach plants (total and morpholino acid (MES)- and ethylenediaminedisuccinic acid (EDDS)-extractable), and Cu uptakes were studied. The behavior of Cu in soil was evaluated by both single and sequential extraction procedures. The highest quantities of Cu in labile forms in the soil, total uptakes, and Cu concentrations in the plants were associated with the application of the two sources that contained Cu chelated by EDTA and/or DTPA. The fertilizers containing these Cu chelates represent a promising approach to achieve high levels of agronomic biofortification. The stronger correlations obtained between low-molecular-weight organic acid-extractable Cu in soil and the Cu concentrations and Cu uptakes by the plants show the suitability of this soil extraction method for predicting Cu available to spinach plants.

Endmember extraction from hyperspectral image based on discrete firefly algorithm (EE-DFA)

NASA Astrophysics Data System (ADS)

Zhang, Chengye; Qin, Qiming; Zhang, Tianyuan; Sun, Yuanheng; Chen, Chao

2017-04-01

This study proposed a novel method to extract endmembers from hyperspectral image based on discrete firefly algorithm (EE-DFA). Endmembers are the input of many spectral unmixing algorithms. Hence, in this paper, endmember extraction from hyperspectral image is regarded as a combinational optimization problem to get best spectral unmixing results, which can be solved by the discrete firefly algorithm. Two series of experiments were conducted on the synthetic hyperspectral datasets with different SNR and the AVIRIS Cuprite dataset, respectively. The experimental results were compared with the endmembers extracted by four popular methods: the sequential maximum angle convex cone (SMACC), N-FINDR, Vertex Component Analysis (VCA), and Minimum Volume Constrained Nonnegative Matrix Factorization (MVC-NMF). What's more, the effect of the parameters in the proposed method was tested on both synthetic hyperspectral datasets and AVIRIS Cuprite dataset, and the recommended parameters setting was proposed. The results in this study demonstrated that the proposed EE-DFA method showed better performance than the existing popular methods. Moreover, EE-DFA is robust under different SNR conditions.

Ethanol production from bamboo using mild alkaline pre-extraction followed by alkaline hydrogen peroxide pretreatment.

PubMed

Yuan, Zhaoyang; Wen, Yangbing; Kapu, Nuwan Sella

2018-01-01

A sequential two-stage pretreatment process comprising alkaline pre-extraction and alkaline hydrogen peroxide pretreatment (AHP) was investigated to convert bamboo carbohydrates into bioethanol. The results showed that mild alkaline pre-extraction using 8% (w/w) sodium hydroxide (NaOH) at 100°C for 180min followed by AHP pretreatment with 4% (w/w) hydrogen peroxide (H 2 O 2 ) was sufficient to generate a substrate that could be efficiently digested with low enzyme loadings. Moreover, alkali pre-extraction enabled the use of lower H 2 O 2 charges in AHP treatment. Two-stage pretreatment followed by enzymatic hydrolysis with only 9FPU/g cellulose led to the recovery of 87% of the original sugars in the raw feedstock. The use of the pentose-hexose fermenting Saccharomyces cerevisiae SR8u strain enabled the utilization of 95.7% sugars in the hydrolysate to reach 4.6%w/v ethanol titer. The overall process also enabled the recovery of 62.9% lignin and 93.8% silica at high levels of purity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sequential estimation and satellite data assimilation in meteorology and oceanography

NASA Technical Reports Server (NTRS)

Ghil, M.

1986-01-01

The role of dynamics in estimating the state of the atmosphere and ocean from incomplete and noisy data is discussed and the classical applications of four-dimensional data assimilation to large-scale atmospheric dynamics are presented. It is concluded that sequential updating of a forecast model with continuously incoming conventional and remote-sensing data is the most natural way of extracting the maximum amount of information from the imperfectly known dynamics, on the one hand, and the inaccurate and incomplete observations, on the other.

Sequential injection ionic liquid dispersive liquid-liquid microextraction for thallium preconcentration and determination with flame atomic absorption spectrometry.

PubMed

Anthemidis, Aristidis N; Ioannou, Kallirroy-Ioanna G

2012-08-01

A novel, automatic on-line sequential injection dispersive liquid-liquid microextraction (SI-DLLME) method, based on 1-hexyl-3-methylimidazolium hexafluorophosphate ([Hmim][PF(6)]) ionic liquid as an extractant solvent was developed and demonstrated for trace thallium determination by flame atomic absorption spectrometry. The ionic liquid was on-line fully dispersed into the aqueous solution in a continuous flow format while the TlBr(4)(-) complex was easily migrated into the fine droplets of the extractant due to the huge contact area of them with the aqueous phase. Furthermore, the extractant was simply retained onto the surface of polyurethane foam packed into a microcolumn. No specific conditions like low temperature are required for extractant isolation. All analytical parameters of the proposed method were investigated and optimized. For 15 mL of sample solution, an enhancement factor of 290, a detection limit of 0.86 μg L(-1) and a precision (RSD) of 2.7% at 20.0 μg L(-1) Tl(I) concentration level, was obtained. The developed method was evaluated by analyzing certified reference materials while good recoveries from environmental and biological samples proved that present method was competitive in practical applications.

Inhibitory effect of the Pseudobrickellia brasiliensis (Spreng) R.M. King & H. Rob. aqueous extract on human lymphocyte proliferation and IFN-γ and TNF-α production in vitro

PubMed Central

Almeida, V.G.; Avelar-Freitas, B.A.; Santos, M.G.; Costa, L.A.; Silva, T.J.; Pereira, W.F.; Amorim, M.L.L.; Grael, C.F.F.; Gregório, L.E.; Rocha-Vieira, E.; Brito-Melo, G.E.A.

2017-01-01

Pseudobrickellia brasiliensis (Asteraceae) is a plant commonly known as arnica-do-campo and belongs to the native flora of the Brazilian Cerrado. The alcoholic extract of the plant has been used as an anti-inflammatory agent in folk medicine, but the biological mechanism of action has not been elucidated. The present study evaluated the composition of P. brasiliensis aqueous extract and its effects on pro-inflammatory cytokine production and lymphocyte proliferation. The extracts were prepared by sequential maceration of P. brasiliensis leaves in ethanol, ethyl acetate, and water. Extract cytotoxicity was evaluated by trypan blue exclusion assay, and apoptosis and necrosis were measured by staining with annexin V-FITC and propidium iodide. The ethanolic (ETA) and acetate (ACE) extracts showed cytotoxic effects. The aqueous extract (AQU) was not cytotoxic. Peripheral blood mononuclear cells stimulated with phorbol myristate acetate and ionomycin and treated with AQU (100 μg/mL) showed reduced interferon (IFN)-γ and tumor necrosis factor (TNF)-α expression. AQU also inhibited lymphocyte proliferative response after nonspecific stimulation with phytohemagglutinin. The aqueous extract was analyzed by liquid chromatography coupled with photodiode array detection and mass spectrometry. Quinic acid and its derivatives 5-caffeoylquinic acid and 3,5-dicaffeoylquinic acid, as well as the flavonoids luteolin and luteolin dihexoside, were detected. All these compounds are known to exhibit anti-inflammatory activity. Taken together, these findings demonstrate that P. brasiliensis aqueous extract can inhibit the pro-inflammatory cytokine production and proliferative response of lymphocytes. These effects may be related to the presence of chemical substances with anti-inflammatory actions previously reported in scientific literature. PMID:28700031

Comparative anthelmintic activity investigation of selected ethno-medicinal weeds

NASA Astrophysics Data System (ADS)

Pueblos, Kirstin Rhys S.; Bajalla, Mark; Pacheco, Dixie; Ganot, Sheila; Paig, Daisy; Tapales, Radyn; Lagare, Jeanne; Quimque, Mark Tristan J.

2017-01-01

Helminth infections are one of the seriously neglected potent diseases in many parts of the world. The problems of parasitic helminthes becoming resistant to currently available anthelmintic drugs pose a challenge for the search - relying on natural products - for new and better anthelmintics. In this paper, four abundant Philippine weeds: Chrysopogon aciculatus Trin. Cyperus brevifolius Rottb., Ruellia tuberosa Linn. and Saccharum spontaneum Linn. were investigated for their anthelmintic activities to establish basis of their folkloric claim. The hexane-soluble and chloroform-soluble extracts were obtained through sequential solvent partitioning of the crude ethanolic extract of the air-dried aerial part of each plant sample. Meanwhile, the decoction was obtained from fresh aerial part of the plant samples. All extracts were then subjected to in vitro anthelmintic screening at different concentration as per method of Ghosh, et al. against African nightcrawler earthworms (Eudrillus euginiae) in which the activity of the extracts was determined by correlation with time. The anthelmintic bioassay results revealed a dose-dependent toxicity relationship. It indicated relatively low anthelmintic activities of the decoction of the four plant samples as compared to their corresponding crude ethanol extracts. Among the crude ethanol extracts, C. brevifolius (CBE) gave fastest time to bring about paralysis and death to the test organisms at all concentrations tested. For the hexane extracts, R. tuberosa (RTH) gave better activity among other plant samples. Lastly, among the chloroform-soluble extracts, both that of C. brevifolius (CBC) and R. tuberosa (RTC) comparably showed strongest anthelmintic activities at all tested concentrations, thus, exhibited best anthelmintic activity that is remarkably comparable to the positive control, Mebendazole at the highest concentration tested. In fact, CBC and RTC showed highest anthelmintic potential compared to all extracts tested in this study.

Inhibitory effect of the Pseudobrickellia brasiliensis (Spreng) R.M. King & H. Rob. aqueous extract on human lymphocyte proliferation and IFN-γ and TNF-α production in vitro.

PubMed

Almeida, V G; Avelar-Freitas, B A; Santos, M G; Costa, L A; Silva, T J; Pereira, W F; Amorim, M L L; Grael, C F F; Gregório, L E; Rocha-Vieira, E; Brito-Melo, G E A

2017-07-10

Pseudobrickellia brasiliensis (Asteraceae) is a plant commonly known as arnica-do-campo and belongs to the native flora of the Brazilian Cerrado. The alcoholic extract of the plant has been used as an anti-inflammatory agent in folk medicine, but the biological mechanism of action has not been elucidated. The present study evaluated the composition of P. brasiliensis aqueous extract and its effects on pro-inflammatory cytokine production and lymphocyte proliferation. The extracts were prepared by sequential maceration of P. brasiliensis leaves in ethanol, ethyl acetate, and water. Extract cytotoxicity was evaluated by trypan blue exclusion assay, and apoptosis and necrosis were measured by staining with annexin V-FITC and propidium iodide. The ethanolic (ETA) and acetate (ACE) extracts showed cytotoxic effects. The aqueous extract (AQU) was not cytotoxic. Peripheral blood mononuclear cells stimulated with phorbol myristate acetate and ionomycin and treated with AQU (100 μg/mL) showed reduced interferon (IFN)-γ and tumor necrosis factor (TNF)-α expression. AQU also inhibited lymphocyte proliferative response after nonspecific stimulation with phytohemagglutinin. The aqueous extract was analyzed by liquid chromatography coupled with photodiode array detection and mass spectrometry. Quinic acid and its derivatives 5-caffeoylquinic acid and 3,5-dicaffeoylquinic acid, as well as the flavonoids luteolin and luteolin dihexoside, were detected. All these compounds are known to exhibit anti-inflammatory activity. Taken together, these findings demonstrate that P. brasiliensis aqueous extract can inhibit the pro-inflammatory cytokine production and proliferative response of lymphocytes. These effects may be related to the presence of chemical substances with anti-inflammatory actions previously reported in scientific literature.

Risk assessment of trace metals in an extreme environment sediment: shallow, hypersaline, alkaline, and industrial Lake Acıgöl, Denizli, Turkey.

PubMed

Budakoglu, Murat; Karaman, Muhittin; Kumral, Mustafa; Zeytuncu, Bihter; Doner, Zeynep; Yildirim, Demet Kiran; Taşdelen, Suat; Bülbül, Ali; Gumus, Lokman

2018-02-23

The major and trace element component of 48 recent sediment samples in three distinct intervals (0-10, 10-20, and 20-30 cm) from Lake Acıgöl is described to present the current contamination levels and grift structure of detrital and evaporate mineral patterns of these sediments in this extreme saline environment. The spatial and vertical concentrations of major oxides were not uniform in the each subsurface interval. However, similar spatial distribution patterns were observed for some major element couples, due mainly to the detrital and evaporate origin of these elements. A sequential extraction procedure including five distinct steps was also performed to determine the different bonds of trace elements in the < 60-μ particulate size of recent sediments. Eleven trace elements (Ni, Fe, Cd, Pb, Cu, Zn, As, Co, Cr, Al and Mn) in nine surface and subsurface sediment samples were analyzed with chemical partitioning procedures to determine the trace element percentage loads in these different sequential extraction phases. The obtained accuracy values via comparison of the bulk trace metal loads with the total loads of five extraction steps were satisfying for the Ni, Fe, Cd, Zn, and Co. While, bulk analysis results of the Cu, Ni, and V elements have good correlation with total organic matter, organic fraction of sequential extraction characterized by Cu, As, Cd, and Pb. Shallow Lake Acıgöl sediment is characteristic with two different redox layer a) oxic upper level sediments, where trace metals are mobilized, b) reduced subsurface level, where the trace metals are precipitated.

Development of a syringe pump assisted dynamic headspace sampling technique for needle trap device.

PubMed

Eom, In-Yong; Niri, Vadoud H; Pawliszyn, Janusz

2008-07-04

This paper describes a new approach that combines needle trap devices (NTDs) with a dynamic headspace sampling technique (purge and trap) using a bidirectional syringe pump. The needle trap device is a 22-G stainless steel needle 3.5-in. long packed with divinylbenzene sorbent particles. The same sized needle, without packing, was used for purging purposes. We chose an aqueous mixture of benzene, toluene, ethylbenzene, and p-xylene (BTEX) and developed a sequential purge and trap (SPNT) method, in which sampling (trapping) and purging cycles were performed sequentially by the use of syringe pump with different distribution channels. In this technique, a certain volume (1 mL) of headspace was sequentially sampled using the needle trap; afterwards, the same volume of air was purged into the solution at a high flow rate. The proposed technique showed an effective extraction compared to the continuous purge and trap technique, with a minimal dilution effect. Method evaluation was also performed by obtaining the calibration graphs for aqueous BTEX solutions in the concentration range of 1-250 ng/mL. The developed technique was compared to the headspace solid-phase microextraction method for the analysis of aqueous BTEX samples. Detection limits as low as 1 ng/mL were obtained for BTEX by NTD-SPNT.

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

Favorito, Jessica E.; Luxton, Todd P.; Eick, Matthew J.

Selenium is a trace element found in western US soils, where ingestion of Se-accumulating plants has resulted in livestock fatalities. Therefore, a reliable understanding of Se speciation and bioavailability is critical for effective mitigation. Sequential extraction procedures (SEP) are often employed to examine Se phases and speciation in contaminated soils but may be limited by experimental conditions. We examined the validity of a SEP using X-ray absorption spectroscopy (XAS) for both whole and a sequence of extracted soils. The sequence included removal of soluble, PO4-extractable, carbonate, amorphous Fe-oxide, crystalline Fe-oxide, organic, and residual Se forms. For whole soils, XANES analysesmore » indicated Se(0) and Se(-II) predominated, with lower amounts of Se(IV) present, related to carbonates and Fe-oxides. Oxidized Se species were more elevated and residual/elemental Se was lower than previous SEP results from ICP-AES suggested. For soils from the SEP sequence, XANES results indicated only partial recovery of carbonate, Fe-oxide and organic Se. This suggests Se was incompletely removed during designated extractions, possibly due to lack of mineral solubilization or reagent specificity. Selenium fractions associated with Fe-oxides were reduced in amount or removed after using hydroxylamine HCl for most soils examined. XANES results indicate partial dissolution of solid-phases may occur during extraction processes. This study demonstrates why precautions should be taken to improve the validity of SEPs. Mineralogical and chemical characterizations should be completed prior to SEP implementation to identify extractable phases or mineral components that may influence extraction effectiveness. Sequential extraction procedures can be appropriately tailored for reliable quantification of speciation in contaminated soils.« less

Continued Data Acquisition Development

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

Schwellenbach, David

This task focused on improving techniques for integrating data acquisition of secondary particles correlated in time with detected cosmic-ray muons. Scintillation detectors with Pulse Shape Discrimination (PSD) capability show the most promise as a detector technology based on work in FY13. Typically PSD parameters are determined prior to an experiment and the results are based on these parameters. By saving data in list mode, including the fully digitized waveform, any experiment can effectively be replayed to adjust PSD and other parameters for the best data capture. List mode requires time synchronization of two independent data acquisitions (DAQ) systems: the muonmore » tracker and the particle detector system. Techniques to synchronize these systems were studied. Two basic techniques were identified: real time mode and sequential mode. Real time mode is the preferred system but has proven to be a significant challenge since two FPGA systems with different clocking parameters must be synchronized. Sequential processing is expected to work with virtually any DAQ but requires more post processing to extract the data.« less

[Isolation and purification of seven catechin compounds from fresh tea leaves by semi-preparative liquid chromatography].

PubMed

Gong, Zhihong; Chen, Si; Gao, Jiangtao; Li, Meihong; Wang, Xiaxia; Lin, Jun; Yu, Xiaomin

2017-11-08

An effective and simple method was established to simultaneously purify seven tea catechins (gallocatechin (GC), epigallocatechin (EGC), catechin (C), epigallocatechin-3- O -gallate (EGCG), epicatechin (EC), epigallocatechin-3- O -(3- O -methyl)-gallate (EGCG3"Me) and epicatechin-3- O -gallate (ECG)) from fresh tea leaves by semi-preparative high performance liquid chromatography (HPLC). Fresh leaves of Tieguanyin tea were successively extracted with methanol and chloroform. Then crude catechins were precipitated from the aqueous fraction of chloroform extraction by adding lead subacetate. Crude catechins were used for the isolation of the seven target catechin compounds by semi-preparative HPLC. Methanol-water and acetonitrile-water were sequentially used as mobile phases. After two rounds of semi-preparative HPLC, all target compounds were achieved with high purities (>90%). The proposed method was tested on two additional tea cultivars and showed similar results. This method demonstrated a simple and efficient strategy based on solvent extraction, ion precipitation and semi-preparative HPLC for the preparation of multiple catechins from tea leaves.

Structural diversity of pectins isolated from the Styrian oil-pumpkin (Cucurbita pepo var. styriaca) fruit.

PubMed

Košťálová, Zuzana; Hromádková, Zdenka; Ebringerová, Anna

2013-03-01

To evaluate the seeded fruit biomass of the Styrian oil-pumpkin in view of its pectin component, a series of acidic polysaccharides were isolated by a six-step sequential extraction using hot water, EDTA, dilute HCl (twice) and dilute and stronger NaOH solutions. Chemical, physicochemical and spectroscopy analyses revealed that the first four fractions comprised partially methyl-esterified and acetylated pectins with varying proportions of rhamnogalacturonan regions ramified with galactose- and arabinose-containing side chains and showed considerable polymolecularity. The alkali-extracted polysaccharides contained lower amounts of pectins with homogalacturonan and arabinose-rich rhamnogalacturonan regions next to hemicelluloses prevailing in the last polysaccharide. Using (1)H-(13)C HSQC and HMBC spectroscopy, the resonances of free and methylesterified galacturonic acid residues in the purified acid-extracted pectin were unambiguously established and various diads formed by both residues identified. The results might serve as a basis for searching technological conditions to produce pectin from the oil-pumpkin fruit biomass. Copyright © 2012 Elsevier Ltd. All rights reserved.

Nuclear events of apoptosis in vitro in cell-free mitotic extracts: a model system for analysis of the active phase of apoptosis

PubMed Central

1993-01-01

We have developed a cell-free system that induces the morphological transformations characteristic of apoptosis in isolated nuclei. The system uses extracts prepared from mitotic chicken hepatoma cells following a sequential S phase/M phase synchronization. When nuclei are added to these extracts, the chromatin becomes highly condensed into spherical domains that ultimately extrude through the nuclear envelope, forming apoptotic bodies. The process is highly synchronous, and the structural changes are completed within 60 min. Coincident with these morphological changes, the nuclear DNA is cleaved into a nucleosomal ladder. Both processes are inhibited by Zn2+, an inhibitor of apoptosis in intact cells. Nuclear lamina disassembly accompanies these structural changes in added nuclei, and we show that lamina disassembly is a characteristic feature of apoptosis in intact cells of mouse, human and chicken. This system may provide a powerful means of dissecting the biochemical mechanisms underlying the final stages of apoptosis. PMID:8408207

Development of a purification procedure for the isolation of nucleosides from urine prior to mass spectrometric analysis.

PubMed

Dudley, E; El-Shakawi, S; Games, D E; Newton, R P

2000-03-01

A chromatographic separation of nucleosides from urine has been developed in order to facilitate their mass spectrometric analysis for clinical diagnosis. A number of chromatographic resins were studied in order to develop an effective and efficient purification procedure. The optimized sequential protocol comprises a centrifugation, acidification and neutralization step, followed by application of an affinity chromatographic column and finally further separation on an acidic cation exchange column and a basic anion exchanger. This scheme shows effective clean-up of a standard radiolabelled nucleoside with a recovery of 92.5%, and recovery of nucleosides added to urine samples before extraction showed recoveries of 72-82%.

Mining local climate data to assess spatiotemporal dengue fever epidemic patterns in French Guiana.

PubMed

Flamand, Claude; Fabregue, Mickael; Bringay, Sandra; Ardillon, Vanessa; Quénel, Philippe; Desenclos, Jean-Claude; Teisseire, Maguelonne

2014-10-01

To identify local meteorological drivers of dengue fever in French Guiana, we applied an original data mining method to the available epidemiological and climatic data. Through this work, we also assessed the contribution of the data mining method to the understanding of factors associated with the dissemination of infectious diseases and their spatiotemporal spread. We applied contextual sequential pattern extraction techniques to epidemiological and meteorological data to identify the most significant climatic factors for dengue fever, and we investigated the relevance of the extracted patterns for the early warning of dengue outbreaks in French Guiana. The maximum temperature, minimum relative humidity, global brilliance, and cumulative rainfall were identified as determinants of dengue outbreaks, and the precise intervals of their values and variations were quantified according to the epidemiologic context. The strongest significant correlations were observed between dengue incidence and meteorological drivers after a 4-6-week lag. We demonstrated the use of contextual sequential patterns to better understand the determinants of the spatiotemporal spread of dengue fever in French Guiana. Future work should integrate additional variables and explore the notion of neighborhood for extracting sequential patterns. Dengue fever remains a major public health issue in French Guiana. The development of new methods to identify such specific characteristics becomes crucial in order to better understand and control spatiotemporal transmission. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Determination of the Pb, Cr, and Cd distribution patterns with various chlorine additives in the bottom ashes of a low-temperature two-stage fluidized bed incinerator by chemical sequential extraction.

PubMed

Peng, Tzu-Huan; Lin, Chiou-Liang; Wey, Ming-Yen

2015-09-15

A novel low-temperature two-stage fluidized bed (LTTSFB) incinerator has been successfully developed to control heavy-metal emissions during municipal solid waste (MSW) treatment. However, the characteristics of the residual metal patterns during this process are still unclear. The aim of this study was to investigate the metal patterns in the different partitions of the LTTSFB bottom ash by chemical sequential extraction. Artificial waste was used to simulate the MSW. Different parameters including the first-stage temperature, chloride additives, and operating gas velocity were also considered. Results indicated that during the low-temperature treatment process, a high metal mobility phase exists in the first-stage sand bed. The main patterns of Cd, Pb, and Cr observed were the water-soluble, exchangeable, and residual forms, respectively. With the different Cl additives, the results showed that polyvinyl chloride addition increased metal mobility in the LTTSFB bottom ash, while, sodium chloride addition may have reduced metal mobility due to the formation of eutectic material. The second-stage sand bed was found to have a lower risk of metal leaching. The results also suggested that, the residual ashes produced by the LTTSFB system must be taken into consideration given their high metal mobility. Copyright © 2015 Elsevier B.V. All rights reserved.

Speciation of heavy metals Cu, Ni and Zn by modified BCR sequential extraction procedure in sediments from Banten Bay, Banten Province, Indonesia

NASA Astrophysics Data System (ADS)

Lestari; Budiyanto, F.; Hindarti, D.

2018-02-01

Banten Bay is categorized as a marine area that is busy with marine tourism activities, settlements and also industries. One potential impact of the condition is the occurrence of pollution from both industrial and domestic sources, erosion and sedimentation in the coastal environment. Samples were collected from 25 representative stations in April 2016. Chemical speciation of three heavy metals (Cu, Ni, and Zn) was studied using a modified sequential extraction procedure proposed by the European Standard, Measurements and Testing (SM&T) program, formerly the Community Bureau of Reference (BCR). The aims of this study are to determine geochemical speciation of 4 bounds of metal: acid-soluble, reducible, oxidizable and residual, and to assess their impacts in the sediments of Banten Bay, Indonesia. The result shows that the percentage of Copper (45.90-83.75%), Nickel (18.28-65.66%), and Zinc (30.45-79.51%) were mostly accumulated in residual fraction of the total concentrations. The Risk Assessment Code (RAC) reveals that about 0-7.07% of Copper and 1.11-24.35 % of Zinc at sites exist in exchangeable fraction and therefore, they are in low risk category. While 7.34-34.90 of Ni at sites exists in exchangeable fraction and therefore, it is in medium risk category to aquatic environment.

Spatial and Temporal Variability in Sediment P Distribution and Speciation in Coastal Louisiana

NASA Astrophysics Data System (ADS)

Bowes, K.; White, J. R.; Maiti, K.

2017-12-01

Excess loading of phosphorus (P) and nitrogen (N) into aquatic systems leads to degradation of water quality and diminished important ecosystem services. In the Northern Gulf of Mexico (NGOM), excess P and N loading has led to a seasonally present hypoxic area with less than 2 mg/L O2 in bottom waters, approximating 26,000 km2 in 2017. A sequential extraction (SEDEX) method was performed on surficial sediments from five different coastal and shelf sites as a function of distance from the Mississippi River mouth in the NGOM. To better quantify temporal variability in P distribution and speciation, samples were collected during both low (August) and high (May) river flow regimes. Sequential extraction techniques have been successful in separating pools of P into exchangeable or loosely sorbed P, Fe-P, Authigenic-P, Detrital-P, and Organic-P. Preliminary results suggest Authigenic-P is approximately 3-6 times more concentrated in NGOM sediments than all other P pools. Fractionation results did not show a consistent trend with sediment depth. Sediment samples had an average moisture content of 58.72% ± 12.06% and an average bulk density of 0.582 ± 0.275 g/cm3. Continued analysis of P speciation and cycling in NGOM sediments is critical in understanding the driving force behind coastal eutrophication and informing effective nutrient management strategies.

Application of sequential extraction analysis to Pb(II) recovery by zerovalent iron-based particles.

PubMed

Zhu, Neng-Min; Xu, Yan-Sheng; Dai, Lichun; Zhang, Yun-Fei; Hu, Guo-Quan

2018-06-05

Zerovalent iron (ZVI) is an environmental-friendly reactive reagent for recovering heavy metals. However, the detailed recovery mechanism remains unclear due to a lack of quantitative analysis of recovery products. Herein, microscale ZVI, nanoscale ZVI and Ni/Fe nanoparticles were used to recover Pb(II) in aqueous solution and a sequential extraction procedure (SEP) was applied to determine the formed lead species quantitatively. At high initial Pb(II) concentration (500 mg L -1 ), more than 99.5% of Pb(II) was immobilized by Ni/Fe and n-ZVI, whereas m-ZVI caused inferior recovery efficiency (<25%). XRD and XPS results revealed that Pb(II) was reduced to Pb 0 prior to the formation of metal hydroxides as the external shell of ZVI. SEP results showed that the fraction bound to carbonates (PbO), fraction bound to iron oxides and exchangeable fraction were the main lead species conducted by Ni/Fe, n-ZVI and m-ZVI, respectively. Consequently, (co-)precipitation and specific adsorption dominated Pb(II) recovery by Ni/Fe and n-ZVI, whereas m-ZVI conducted Pb(II) recovery mainly via weak adsorption. The reactivity of ZVI toward Pb(II) followed the increasing order of m-ZVI < n-ZVI ≤ Ni/Fe. The detailed mechanisms of Pb(II) recovery conducted by different ZVI were proposed. Copyright © 2018 Elsevier B.V. All rights reserved.

Sequential injection-bead injection-lab-on-valve coupled to high-performance liquid chromatography for online renewable micro-solid-phase extraction of carbamate residues in food and environmental samples.

PubMed

Vichapong, Jitlada; Burakham, Rodjana; Srijaranai, Supalax; Grudpan, Kate

2011-07-01

A sequential injection-bead injection-lab-on-valve system was hyphenated to HPLC for online renewable micro-solid-phase extraction of carbamate insecticides. The carbamates studied were isoprocarb, methomyl, carbaryl, carbofuran, methiocarb, promecarb, and propoxur. LiChroprep(®) RP-18 beads (25-40 μm) were employed as renewable sorbent packing in a microcolumn situated inside the LOV platform mounted above the multiposition valve of the sequential injection system. The analytes sorbed by the microcolumn were eluted using 80% acetonitrile in 0.1% acetic acid before online introduction to the HPLC system. Separation was performed on an Atlantis C-18 column (4.6 × 150 mm, 5 μm) utilizing gradient elution with a flow rate of 1.0 mL/min and a detection wavelength at 270 nm. The sequential injection system offers the means of performing automated handling of sample preconcentration and matrix removal. The enrichment factors ranged between 20 and 125, leading to limits of detection (LODs) in the range of 1-20 μg/L. Good reproducibility was obtained with relative standard deviations of <0.7 and 5.4% for retention time and peak area, respectively. The developed method has been successfully applied to the determination of carbamate residues in fruit, vegetable, and water samples. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Macro- and microscale investigation of selenium speciation in Blackfoot river, Idaho sediments.

PubMed

Oram, Libbie L; Strawn, Daniel G; Marcus, Matthew A; Fakra, Sirine C; Möller, Gregory

2008-09-15

The transport and bioavailability of selenium in the environment is controlled by its chemical speciation. However, knowledge of the biogeochemistry and speciation of Se in streambed sediment is limited. We investigated the speciation of Se in sediment cores from the Blackfoot River (BFR), Idaho using sequential extractions and synchrotron-based micro-X-ray fluorescence (micro-SXRF). We collected micro-SXRF oxidation state maps of Se in sediments, which had not been done on natural sediment samples. Selective extractions showed that most Se in the sediments is present as either (1) nonextractable Se or (2) base extractable Se. Results from micro-SXRF showed three defined species of Se were present in all four samples: Se(-II,O), Se(IV), and Se(VI). Se(-II,O) was the predominant species in samples from one location, and Se(IV) was the predominant species in samples from a second location. Results from both techniques were consistent, and suggested that the predominant species were Se(-II) species associated with recalcitrant organic matter, and Se(IV) species tightly bound to organic materials. This information can be used to predict the biogeochemical cycling and bioavailability of Se in streambed sediment environments.

Combination of HPLC chromatogram and hypoglycemic effect identifies isoflavones as the principal active fraction of Belamcanda chinensis leaf extract in diabetes treatment.

PubMed

Chen, Yan; Wu, Chong-Ming; Dai, Rong-Ji; Li, Liang; Yu, Yu-Hong; Li, Yan; Meng, Wei-Wei; Zhang, Liang; Zhang, Yongqian; Deng, Yu-Lin

2011-02-15

In previous study, we demonstrated the hypoglycemic effect of aqueous extract of Belamcanda chinensis leaves in rats. Here, we separated the aqueous extract of B. chinensis leaves and investigated the spectrum-effect relationships between HPLC chromatograms and hypoglycemic activities of different isolates from B. chinensis leaf extract. Sequential solvent extraction with petroleum ether, chloroform, acetic ester and n-butanol provided several isolates showing similar hypoglycemic activities, making it difficult to discriminate the active fractions. Stepwise elution through HP20 macroporous resin by water, 40% and 95% ethanol provided isolates with distinct hypoglycemic activities, representing a simple, rapid and efficient preparative separation method. Combination of HPLC chromatogram and pharmacological effect targeted a hypoglycemic activity-related region in HPLC chromatogram. Each peak in this region was analyzed by UV spectrum scan. Most of them were flavonoids in which tectoridin and swertisin were known flavonoids with anti-diabetic activities. In together, this work provides a general model of combination of HPLC chromatography and pharmacological effect to study the spectrum-effect relationships of aqueous extract from B. chinensis leaves, which can be used to find principle components of B. chinensis on pharmacological activity. Copyright © 2011 Elsevier B.V. All rights reserved.

The BLAZE language: A parallel language for scientific programming

NASA Technical Reports Server (NTRS)

Mehrotra, P.; Vanrosendale, J.

1985-01-01

A Pascal-like scientific programming language, Blaze, is described. Blaze contains array arithmetic, forall loops, and APL-style accumulation operators, which allow natural expression of fine grained parallelism. It also employs an applicative or functional procedure invocation mechanism, which makes it easy for compilers to extract coarse grained parallelism using machine specific program restructuring. Thus Blaze should allow one to achieve highly parallel execution on multiprocessor architectures, while still providing the user with onceptually sequential control flow. A central goal in the design of Blaze is portability across a broad range of parallel architectures. The multiple levels of parallelism present in Blaze code, in principle, allow a compiler to extract the types of parallelism appropriate for the given architecture while neglecting the remainder. The features of Blaze are described and shows how this language would be used in typical scientific programming.

Characterization of Natural Organic Matter in Low-Carbon Environments: Extraction and Analytical Approaches

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

Fox, Patricia M.; Nico, Peter S.; Tfaily, Malak M.

2017-12-31

Sediment-associated natural organic matter (NOM) is a complex assemblage of organic molecules with a wide range of sizes, functional groups, and structures, which is intricately associated with mineral particles. Organic carbon (OC) concentrations in subsurface sediments are typically 10 to 200 times lower than in surface soils, posing a distinct challenge for characterization. A range of chemical extractions were evaluated for extraction of NOM, and a NOM extraction scheme was developed using a combination of sequential extraction with water (MQ) and sodium pyrophosphate at pH 10 (PP), and purification by dialysis and solid phase extraction in order to isolate differentmore » fractions of sediment-associated NOM. Analysis of these different NOM fractions was then carried out by Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-Vis) spectroscopy, and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS). The OC extraction efficiency of the tested extractions followed the order PP>NaOH>HCl=hydroxylamine hydrochloride>dithionite. Greater concentrations of OC in PP vs NaOH extracts suggest that metal complexation and/or ligand exchange plays an important role in OC stabilization. Characterization of different pools of extraction NOM by FITR shows that the water soluble fraction has a higher fraction of aliphatic and carboxylic groups, while the PP fractions have higher C=C groups. This trend from aliphatic to more aromatic is also supported by the UV-Vis and ESI-FTICR-MS data.« less

Characterization of natural organic matter in low-carbon sediments: Extraction and analytical approaches

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

Fox, Patricia M.; Nico, Peter S.; Tfaily, Malak M.

Sediment-associated natural organic matter (NOM) is a complex assemblage of organic molecules with a wide range of sizes, functional groups, and structures, which is intricately associated with mineral particles. Organic carbon (OC) concentrations in subsurface sediments are typically 10 to 200 times lower than in surface soils, posing a distinct challenge for characterization. A range of chemical extractions were evaluated for extraction of NOM, and a NOM extraction scheme was developed using a combination of sequential extraction with water (MQ) and sodium pyrophosphate at pH 10 (PP), and purification by dialysis and solid phase extraction in order to isolate differentmore » fractions of sediment-associated NOM. Analysis of these different NOM fractions was then carried out by Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-Vis) spectroscopy, and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS). The OC extraction efficiency of the tested extractions followed the order PP>NaOH>HCl=hydroxylamine hydrochloride>dithionite. Greater concentrations of OC in PP vs NaOH extracts suggest that metal complexation and/or ligand exchange plays an important role in OC stabilization. Characterization of different pools of extraction NOM by FITR shows that the water soluble fraction has a higher fraction of aliphatic and carboxylic groups, while the PP fractions have higher C=C groups. This trend from aliphatic to more aromatic is also supported by the UV-Vis and ESI-FTICR-MS data.« less

CFD simulation of hemodynamics in sequential and individual coronary bypass grafts based on multislice CT scan datasets.

PubMed

Hajati, Omid; Zarrabi, Khalil; Karimi, Reza; Hajati, Azadeh

2012-01-01

There is still controversy over the differences in the patency rates of the sequential and individual coronary artery bypass grafting (CABG) techniques. The purpose of this paper was to non-invasively evaluate hemodynamic parameters using complete 3D computational fluid dynamics (CFD) simulations of the sequential and the individual methods based on the patient-specific data extracted from computed tomography (CT) angiography. For CFD analysis, the geometric model of coronary arteries was reconstructed using an ECG-gated 64-detector row CT. Modeling the sequential and individual bypass grafting, this study simulates the flow from the aorta to the occluded posterior descending artery (PDA) and the posterior left ventricle (PLV) vessel with six coronary branches based on the physiologically measured inlet flow as the boundary condition. The maximum calculated wall shear stress (WSS) in the sequential and the individual models were estimated to be 35.1 N/m(2) and 36.5 N/m(2), respectively. Compared to the individual bypass method, the sequential graft has shown a higher velocity at the proximal segment and lower spatial wall shear stress gradient (SWSSG) due to the flow splitting caused by the side-to-side anastomosis. Simulated results combined with its surgical benefits including the requirement of shorter vein length and fewer anastomoses advocate the sequential method as a more favorable CABG method.

Monitoring of electrokinetic removal of heavy metals in tailing-soils using sequential extraction analysis.

PubMed

Kim, S O; Kim, K W

2001-08-17

This research focused on the monitoring of the electrokinetic removal of heavy metals from tailing-soils, and emphasizes the dependency of removal efficiencies upon their physico-chemical states, as demonstrated by the different extraction methods adopted, which included aqua regia and sequential extraction. The tailing-soils examined contained high concentrations of target metal contaminants (Cd=179mgkg(-1), Cu=207mgkg(-1), Pb=5175mgkg(-1), and Zn=7600mgkg(-1)). The removal efficiencies of the different metals were significantly influenced by their speciations, mobilities and affinities (adsorption capacities) in the soil matrix. The removal efficiencies of mobile and weakly bound fractions, such as the exchangeable fraction were more than 90% by electrokinetic treatment, but strongly bound fractions, such as the organically bound species and residual fraction were not significantly removed (less than 30% removal efficiencies). In accordance with the general sequence of mobilities of heavy metals in soils, the removal efficiencies of more mobile heavy metals (Cd, Cu, and Zn) were higher than that of less mobile heavy metal (Pb).

Sequential co-production of biodiesel and bioethanol with spent coffee grounds.

PubMed

Kwon, Eilhann E; Yi, Haakrho; Jeon, Young Jae

2013-05-01

The sequential co-production of bioethanol and biodiesel from spent coffee grounds was investigated. The direct conversion of bioethanol from spent coffee grounds was not found to be a desirable option because of the relatively slow enzymatic saccharification behavior in the presence of triglycerides and the free fatty acids (FFAs) found to exist in the raw materials. Similarly, the direct transformation of the spent coffee grounds into ethanol without first extracting lipids was not found to be a feasible alternative. However, the crude lipids extracted from the spent coffee grounds were themselves converted into fatty acid methyl ester (FAME) and fatty acid ethyl ester (FAEE) via the non-catalytic biodiesel transesterification reaction. The yields of bioethanol and biodiesel were 0.46 g g(-1) and 97.5±0.5%, which were calculated based on consumed sugar and lipids extracted from spent coffee grounds respectively. Thus, this study clearly validated our theory that spent coffee grounds could be a strong candidate for the production of bioethanol and biodiesel. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fractionation study in bioleached metallurgy wastes using six-step sequential extraction.

PubMed

Krasnodebska-Ostrega, Beata; Pałdyna, Joanna; Kowalska, Joanna; Jedynak, Łukasz; Golimowski, Jerzy

2009-08-15

The stored metallurgy wastes contain residues from ore processing operations that are characterized by relatively high concentrations of heavy metals. The bioleaching process makes use of bacteria to recover elements from industrial wastes and to decrease potential risk of environmental contamination. Wastes were treated by solutions containing bacteria. In this work, the optimized six-stage sequential extraction procedure was applied for the fractionation of Ni, Cr, Fe, Mn, Cu and Zn in iron-nickel metallurgy wastes deposited in Southern Poland (Szklary). Fractionation and total concentrations of elements in wastes before and after various bioleaching treatments were studied. Analyses of the extracts were performed by ICP-MS and FAAS. To achieve the most effective bioleaching of Zn, Cr, Ni, Cu, Mn, Fe the usage of both autotrophic and heterotrophic bacteria in sequence, combined with flushing of the residue after bioleaching is required. 80-100% of total metal concentrations were mobilized after the proposed treatment. Wastes treated according to this procedure could be deposited without any risk of environmental contamination and additionally the metals could be recovered for industrial purposes.

Geochemical fractionation of metals and metalloids in tailings and appraisal of environmental pollution in the abandoned Musina Copper Mine, South Africa.

PubMed

Gitari, M W; Akinyemi, S A; Ramugondo, L; Matidza, M; Mhlongo, S E

2018-04-30

The economic benefits of mining industry have often overshadowed the serious challenges posed to the environments through huge volume of tailings generated and disposed in tailings dumps. Some of these challenges include the surface and groundwater contamination, dust, and inability to utilize the land for developmental purposes. The abandoned copper mine tailings in Musina (Limpopo province, South Africa) was investigated for particle size distribution, mineralogy, physicochemical properties using arrays of granulometric, X-ray diffraction, and X-ray fluorescence analyses. A modified Community Bureau of Reference (BCR) sequential chemical extraction method followed by inductively coupled plasma mass spectrometry/atomic emission spectrometry (ICP-MS/AES) technique was employed to assess bioavailability of metals. Principal component analysis was performed on the sequential extraction data to reveal different loadings and mobilities of metals in samples collected at various depths. The pH ranged between 7.5 and 8.5 (average ≈ 8.0) indicating alkaline medium. Samples composed mostly of poorly grated sands (i.e. 50% fine sand) with an average permeability of about 387.6 m/s. Samples have SiO 2 /Al 2 O 3 and Na 2 O/(Al 2 O 3  + SiO 2 ) ratios and low plastic index (i.e. PI ≈ 2.79) suggesting non-plastic and very low dry strength. Major minerals were comprised of quartz, epidote, and chlorite while the order of relative abundance of minerals in minor quantities is plagioclase > muscovite > hornblende > calcite > haematite. The largest percentage of elements such as As, Cd and Cr was strongly bound to less extractable fractions. Results showed high concentration and easily extractable Cu in the Musina Copper Mine tailings, which indicates bioavailability and poses environmental risk and potential health risk of human exposure. Principal component analysis revealed Fe-oxide/hydroxides, carbonate and clay components, and copper ore process are controlling the elements distribution.

Integrating ecotoxicity and chemical approaches to compare the effects of ZnO nanoparticles, ZnO bulk, and ZnCl2 on plants and microorganisms in a natural soil.

PubMed

García-Gómez, C; Babin, M; Obrador, A; Álvarez, J M; Fernández, M D

2015-11-01

This work compared the toxicity of ZnO nanoparticles (ZnO-NPs), ZnO bulk, and ZnCl2 on microbial activity (C and N transformations and dehydrogenase and phosphatase activities) and their uptake and toxic effects (emergence, root elongation, and shoot growth) on three plant species namely wheat, radish, and vetch in a natural soil at 1000 mg Zn kg(-1). Additionally, plants were also tested at 250 mg Zn kg(-1). The effects of the chemical species on Zn extractability in soil were studied by performing single and sequential extractions. ZnCl2-1000 presented the highest toxicity for both taxonomic groups. For microorganisms, ZnO-NPs demonstrated adverse effects on all measured parameters, except on N transformations. The effects of both ZnO forms were similar. For plants, ZnO-NPs affected the growth of more plant species than ZnO bulk, although the effects were small in all cases. Regarding accumulation, the total Zn amounts were higher in plants exposed to ZnO-NP than those exposed to ZnO bulk, except for vetch shoots. The soil sequential extraction revealed that the Zn concentration in the most labile forms (water soluble (WS) and exchangeable (EX)) was similar in soil treated with ZnO (NP and bulk) and lower than that of ZnCl2-treated soil, indicating the higher availability of the ionic forms. The strong correlations obtained between WS-Zn fraction and the Zn concentrations in the roots, shoots, and the effects on shoot weight show the suitability of this soil extraction method for predicting bioavailable Zn soil for the three plant species when it was added as ZnO-NPs, ZnO bulk, or ZnCl2. In this work, the hazard associated with the ZnO-NPs was similar to ZnO bulk in most cases.

Quantitative proteomic characterization of the lung extracellular matrix in chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis.

PubMed

Åhrman, Emma; Hallgren, Oskar; Malmström, Lars; Hedström, Ulf; Malmström, Anders; Bjermer, Leif; Zhou, Xiao-Hong; Westergren-Thorsson, Gunilla; Malmström, Johan

2018-03-01

Remodeling of the extracellular matrix (ECM) is a common feature in lung diseases such as chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). Here, we applied a sequential tissue extraction strategy to describe disease-specific remodeling of human lung tissue in disease, using end-stages of COPD and IPF. Our strategy was based on quantitative comparison of the disease proteomes, with specific focus on the matrisome, using data-independent acquisition and targeted data analysis (SWATH-MS). Our work provides an in-depth proteomic characterization of human lung tissue during impaired tissue remodeling. In addition, we show important quantitative and qualitative effects of the solubility of matrisome proteins. COPD was characterized by a disease-specific increase in ECM regulators, metalloproteinase inhibitor 3 (TIMP3) and matrix metalloproteinase 28 (MMP-28), whereas for IPF, impairment in cell adhesion proteins, such as collagen VI and laminins, was most prominent. For both diseases, we identified increased levels of proteins involved in the regulation of endopeptidase activity, with several proteins belonging to the serpin family. The established human lung quantitative proteome inventory and the construction of a tissue-specific protein assay library provides a resource for future quantitative proteomic analyses of human lung tissues. We present a sequential tissue extraction strategy to determine changes in extractability of matrisome proteins in end-stage COPD and IPF compared to healthy control tissue. Extensive quantitative analysis of the proteome changes of the disease states revealed altered solubility of matrisome proteins involved in ECM regulators and cell-ECM communication. The results highlight disease-specific remodeling mechanisms associated with COPD and IPF. Copyright © 2018 Elsevier B.V. All rights reserved.

Geochemistry and mineralogy of arsenic in mine wastes and stream sediments in a historic metal mining area in the UK.

PubMed

Rieuwerts, J S; Mighanetara, K; Braungardt, C B; Rollinson, G K; Pirrie, D; Azizi, F

2014-02-15

Mining generates large amounts of waste which may contain potentially toxic elements (PTE), which, if released into the wider environment, can cause air, water and soil pollution long after mining operations have ceased. The fate and toxicological impact of PTEs are determined by their partitioning and speciation and in this study, the concentrations and mineralogy of arsenic in mine wastes and stream sediments in a former metal mining area of the UK are investigated. Pseudo-total (aqua-regia extractable) arsenic concentrations in all samples from the mining area exceeded background and guideline values by 1-5 orders of magnitude, with a maximum concentration in mine wastes of 1.8×10(5)mgkg(-1) As and concentrations in stream sediments of up to 2.5×10(4)mgkg(-1) As, raising concerns over potential environmental impacts. Mineralogical analysis of the wastes and sediments was undertaken by scanning electron microscopy (SEM) and automated SEM-EDS based quantitative evaluation (QEMSCAN®). The main arsenic mineral in the mine waste was scorodite and this was significantly correlated with pseudo-total As concentrations and significantly inversely correlated with potentially mobile arsenic, as estimated from the sum of exchangeable, reducible and oxidisable arsenic fractions obtained from a sequential extraction procedure; these findings correspond with the low solubility of scorodite in acidic mine wastes. The work presented shows that the study area remains grossly polluted by historical mining and processing and illustrates the value of combining mineralogical data with acid and sequential extractions to increase our understanding of potential environmental threats. Copyright © 2013 Elsevier B.V. All rights reserved.

Economic Analysis of an Integrated Annatto Seeds-Sugarcane Biorefinery Using Supercritical CO2 Extraction as a First Step

PubMed Central

Albarelli, Juliana Q.; Santos, Diego T.; Cocero, María José; Meireles, M. Angela A.

2016-01-01

Recently, supercritical fluid extraction (SFE) has been indicated to be utilized as part of a biorefinery, rather than as a stand-alone technology, since besides extracting added value compounds selectively it has been shown to have a positive effect on the downstream processing of biomass. To this extent, this work evaluates economically the encouraging experimental results regarding the use of SFE during annatto seeds valorization. Additionally, other features were discussed such as the benefits of enhancing the bioactive compounds concentration through physical processes and of integrating the proposed annatto seeds biorefinery to a hypothetical sugarcane biorefinery, which produces its essential inputs, e.g., CO2, ethanol, heat and electricity. For this, first, different configurations were modeled and simulated using the commercial simulator Aspen Plus® to determine the mass and energy balances. Next, each configuration was economically assessed using MATLAB. SFE proved to be decisive to the economic feasibility of the proposed annatto seeds-sugarcane biorefinery concept. SFE pretreatment associated with sequential fine particles separation process enabled higher bixin-rich extract production using low-pressure solvent extraction method employing ethanol, meanwhile tocotrienols-rich extract is obtained as a first product. Nevertheless, the economic evaluation showed that increasing tocotrienols-rich extract production has a more pronounced positive impact on the economic viability of the concept. PMID:28773616

Characterization of pH-fractionated humic acids derived from Chinese weathered coal.

PubMed

Zhang, Shuiqin; Yuan, Liang; Li, Wei; Lin, Zhian; Li, Yanting; Hu, Shuwen; Zhao, Bingqiang

2017-01-01

To reduce the compositional and structural heterogeneity of humic acids (HAs) and achieve better use of HA resources, in this study, we report a new sequential dissolution method for HAs derived from Chinese weathered coal. This method was used to separate HAs into seven fractions by adjusting the pH (3-10) of the extraction solution. The results showed that the HA fractions derived from Chinese weathered coal were concentrated up to 90.31% in the lower pH solutions (3-7). The compositional and structural characteristics of the HA fractions were determined by elemental analysis; ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), and solid-state 13 C-nuclear magnetic resonance (NMR) spectroscopies; and other techniques. The results showed significant differences among the HA fractions. The concentrations of the total acidic groups and the carboxyl groups decreased with the increasing pH of the extraction solution. However, the HA fractions derived from extraction solutions with pH 3-4 had relatively lower aromaticity but a higher protonated carbon content. The HA fractions derived from extraction solutions with pH 6-7 had the highest aromaticity and the greatest abundance of COO/N-C=O. This study demonstrated that adjusting the pH of the extraction solution is one way to fractionate HAs from Chinese weathered coal and to obtain HA fractions with compositions and structures that could serve as useful material for study and utilization. Copyright © 2016 Elsevier Ltd. All rights reserved.

Uranium decay daughters from isolated mines: Accumulation and sources.

PubMed

Cuvier, A; Panza, F; Pourcelot, L; Foissard, B; Cagnat, X; Prunier, J; van Beek, P; Souhaut, M; Le Roux, G

2015-11-01

This study combines in situ gamma spectrometry performed at different scales, in order to accurately locate the contamination pools, to identify the concerned radionuclides and to determine the distribution of the contaminants from soil to bearing phase scale. The potential mobility of several radionuclides is also evaluated using sequential extraction. Using this procedure, an accumulation area located downstream of a former French uranium mine and concentrating a significant fraction of radioactivity is highlighted. We report disequilibria in the U-decay chains, which are likely related to the processes implemented on the mining area. Coupling of mineralogical analyzes with sequential extraction allow us to highlight the presence of barium sulfate, which may be the carrier of the Ra-226 activities found in the residual phase (Ba(Ra)SO4). In contrast, uranium is essentially in the reducible fraction and potentially trapped in clay-iron coatings located on the surface of minerals. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cadmium partition in river sediments from an area affected by mining activities.

PubMed

Vasile, Georgiana D; Vlădescu, Luminiţa

2010-08-01

In this paper, the cadmium distribution in Certej River sediments in an area seriously affected by intense mining activities has been studied. The main objective of this study was the evaluation of partition of this metal into different operational defined fractions by sequential extractions. Community Bureau of Reference (BCR) sequential extraction was used to isolate different fractions. The sediment quality was assessed both upstream and downstream the pollution input points, along the Certej River, in order to reveal a possible accumulation of cadmium in sediments and the seasonal changes in cadmium concentrations in BCR sediment phases. Our results reveal that most of the cadmium content is divided between both the soluble and iron and manganese hydrated oxide fractions. Based on total cadmium concentrations in sediments, the enrichment factors were estimated using aluminum as normalizing element and the regression curve Cd/Al corresponding to the geochemical background of the studied area.

Investigations of Cu, Pb and Zn partitioning by sequential extraction in harbour sediments after electrodialytic remediation.

PubMed

Kirkelund, Gunvor M; Ottosen, Lisbeth M; Villumsen, Arne

2010-05-01

Electrodialytic remediation was used to remove Cu, Zn and Pb from three different contaminated harbour sediments. Electrodialytic experiments lasting 2 and 4 weeks were performed and 48-86% Cu, 74-90% Zn and 62-88% Pb were removed from the different sediments and the removal increased with longer remediation time. A three step sequential extraction scheme (BCR), with an extra residual step, was used to evaluate the heavy metal distribution in the sediments before and after electrodialytic remediation. Cu was mainly associated with the oxidisable phase of the sediment, both before and after remediation. Zn and Pb were found in the exchangeable and reducible phases before remediation. Zn was still found in the exchangeable and reducible phases after remediation, whereas most Pb was removed from these phases during electrodialytic remediation. Copyright 2010 Elsevier Ltd. All rights reserved.

Sequential Learning and Recognition of Comprehensive Behavioral Patterns Based on Flow of People

NASA Astrophysics Data System (ADS)

Gibo, Tatsuya; Aoki, Shigeki; Miyamoto, Takao; Iwata, Motoi; Shiozaki, Akira

Recently, surveillance cameras have been set up everywhere, for example, in streets and public places, in order to detect irregular situations. In the existing surveillance systems, as only a handful of surveillance agents watch a large number of images acquired from surveillance cameras, there is a possibility that they may miss important scenes such as accidents or abnormal incidents. Therefore, we propose a method for sequential learning and the recognition of comprehensive behavioral patterns in crowded places. First, we comprehensively extract a flow of people from input images by using optical flow. Second, we extract behavioral patterns on the basis of change-point detection of the flow of people. Finally, in order to recognize an observed behavioral pattern, we draw a comparison between the behavioral pattern and previous behavioral patterns in the database. We verify the effectiveness of our approach by placing a surveillance camera on a campus.

New data on the mobility of Pt emitted from catalytic converters.

PubMed

Fliegel, Daniel; Berner, Zsolt; Eckhardt, Detlef; Stüben, Doris

2004-05-01

The mobility and speciation of Pt was investigated in dust deposited in highway tunnels and in gully sediments. For this, a sequential extraction technique was used in combination with a microwave digestion procedure, followed by detection of Pt with high resolution ICP-MS. A digestion procedure using HNO(3)/HCl/H(2)O(2) was developed and its efficiency tested for environmental materials. Total Pt contents ranged from approximately 100 to 300 microg/kg. The high share of chemically mobile Pt in the tunnel dust (up to about 40%) indicates that Pt is predominantly emitted in a mobile form from the converter. The absence of a mobile fraction in the gully sediment is explained by the elution of Pt by run-off. Except for the mobile and easily mobilised fractions none of the other fractions of the sequential extraction contains Pt, neither in the dust samples nor in the gully sediment.

Formation of iron nanoparticles and increase in iron reactivity in mineral dust during simulated cloud processing.

PubMed

Shi, Zongbo; Krom, Michael D; Bonneville, Steeve; Baker, Alex R; Jickells, Timothy D; Benning, Liane G

2009-09-01

The formation of iron (Fe) nanoperticles and increase in Fe reactivity in mineral dust during simulated cloud processing was investigated using high-resolution microscopy and chemical extraction methods. Cloud processing of dust was experimentally simulated via an alternation of acidic (pH 2) and circumneutral conditions (pH 5-6) over periods of 24 h each on presieved (<20 microm) Saharan soil and goethite suspensions. Microscopic analyses of the processed soil and goethite samples reveal the neo-formation of Fe-rich nanoparticle aggregates, which were not found initially. Similar Fe-rich nanoparticles were also observed in wet-deposited Saharen dusts from the western Mediterranean but not in dry-deposited dust from the eastern Mediterranean. Sequential Fe extraction of the soil samples indicated an increase in the proportion of chemically reactive Fe extractable by an ascorbate solution after simulated cloud processing. In addition, the sequential extractions on the Mediterranean dust samples revealed a higher content of reactive Fe in the wet-deposited dust compared to that of the dry-deposited dust These results suggestthat large variations of pH commonly reported in aerosol and cloud waters can trigger neo-formation of nanosize Fe particles and an increase in Fe reactivity in the dust

Larvicidal, ovicidal and repellent activities of marine sponge Cliona celata (Grant) extracts against Anopheles stephensi Liston (Diptera: Culicidae).

PubMed

Reegan, Appadurai Daniel; Kinsalin, Arokia Valan; Paulraj, Michael Gabriel; Ignacimuthu, Savarimuthu

2015-01-01

To evaluate the larvicidal, ovicidal and repellent properties of solvent extracts of marine sponge Cliona celata (C. celata) (Grant) against the malarial vector Anopheles stephensi (An. stephensi) Liston. Marine sponge C. celata was thoroughly washed with distilled water and shade dried for 48 h. Then the sponges were homogenized and extracted sequentially with hexane, ethyl acetate and methanol. Larvicidal and ovicidal activities were tested at four different concentrations viz., 62.5, 125.0, 250.0 and 500.0 ppm. For repellent study extracts were taken in three different concentrations viz., 5.0, 2.5, 1.0 mg/cm at. Among the three solvent extracts of C. celata, methanol extract showed the highest larvicidal activity at 500 ppm against the fourth instar larvae of An. stephensi. The LC50 and LC90 values of C. celata methanol extract were recorded as 80.61 and 220.81 ppm against An. stephensi larvae respectively. High ovicidal activity of 91.2% was recorded at 500 ppm concentration of methanol extract. The haxane extract was found to be the most effective protectant against the adult female mosquitoes of An. stephensi. The mean protection time recorded in hexane extract was up to 245 min at 5 mg/cm(2) dosage against An. stephensi adults. The screening results suggest that the hexane and methanol extracts of C. celata are promising in mosquito control. Considering these bioactivities, C. celata could be probed further to obtain some novel pesticidal molecules. Copyright © 2015 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

Applications of derivatization reactions to trace organic compounds during sample preparation based on pressurized liquid extraction.

PubMed

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

2013-06-28

Pressurized liquid extraction (PLE) is an exhaustive technique used for the extraction of analytes from solid samples. Temperature, pressure, solvent type and volume, and the addition of other reagents notably influence the efficiency of the extraction. The analytical applications of this technique can be improved by coupling with appropriate derivatization reactions. The aim of this review is to discuss the recent applications of the sequential combination of PLE with derivatization and the approaches that involve simultaneous extraction and in situ derivatization. The potential of the latest developments to the trace analysis of environmental, food and biological samples is also analyzed. Copyright © 2013 Elsevier B.V. All rights reserved.

Comparative uptake of plutonium from soils by Brassica juncea and Helianthus annuus.

PubMed

Lee, J H; Hossner, L R; Attrep, M; Kung, K S

2002-01-01

Plutonium uptake by Brassica juncea (Indian mustard) and Helianthus annuus (sunflower) from soils with varying chemical composition and contaminated with Pu complexes (Pu-nitrate [239Pu(NO3)4], Pu-citrate [239Pu(C6H5O7)], and Pu-diethylenetriaminepentaacetic acid (Pu-DTPA [239Pu-C14H23O10N3]) was investigated. Sequential extraction of soils incubated with applied Pu was used to determine the distribution of Pu in the various soil fractions. The initial Pu activity levels in soils were 44.40-231.25 Bq g(-1) as Pu-nitrate Pu-citrate, or Pu-DTPA. A difference in Pu uptake between treatments of Pu-nitrate and Pu-citrate without chelating agent was observed only with Indian mustard in acidic Crowley soil. The uptake of Pu by plants was increased with increasing DTPA rates, however, the Pu concentration of plants was not proportionally increased with increasing application rate of Pu to soil. Plutonium uptake from Pu-DTPA was significantly higher from the acid Crowley soil than from the calcareous Weswood soil. The uptake of Pu from the soils was higher in Indian mustard than in sunflower. Sequential extraction of Pu showed that the ion-exchangeable Pu fraction in soils was dramatically increased with DTPA treatment and decreased with time of incubation. Extractability of Pu in all fractions was not different when Pu-nitrate and Pu-citrate were applied to the same soil. More Pu was associated with the residual Pu fraction without DTPA application. Consistent trends with time of incubation for other fractions were not apparent. The ion-exchangeable fraction, assumed as plant-available Pu, was significantly higher in acid soil compared with calcareous soil with or without DTPA treatment. When the calcareous soil was treated with DTPA, the ion-exchangeable Pu was comparatively less influenced. This fraction in the soil was more affected with time of incubation. The lowest extractable Pu was from a pH 6.55 Crockett soil that contained the highest clay compared to the other two soils. Extractable soil Pu was largely affected by soil pH and the amounts of clay, salt, metal oxide, and carbonate.

CONTINUOUS DISSOLVER EXTRACTOR FOR PROCESSING METAL

DOEpatents

Lemon, R.B.; Buckham, J.A.

1959-02-01

An apparatus is presented for the continuous dissolution of metal slugs in an aqueous acid and sequential continuous extraction of selected metal values from the acid solution by counter-current contact with an organic solvent. The apparatus comprises a cylindrical tank divided into upper and lower sections. Dissolution of the metal slug takes place in the lower section and the solution so produced is continuously fed to the topmost plate of the upper extraction section. An immiscible organic extractant is continuously passed by a pulsing pump into the lowermost unit of the extraction section. Suitable piping and valving permits of removing the aqueous raffinate solution from the lowermost portion of the extraction section, and simultaneous removal of organic solvent extractant containing the desired product from the uppermost portion of the extraction section.

Comparison of leaching characteristics of heavy metals in APC residue from an MSW incinerator using various extraction methods.

PubMed

Chiang, Kung-Yuh; Tsai, Chen-Chiu; Wang, Kuen-Sheng

2009-01-01

This study investigates four extraction methods (water extraction, toxicity characteristics leaching procedure (TCLP), modified TCLP with pH control, and sequential chemical extraction (SCE)), each representing different liquid-to-solid (L/S) ratios, pH controls, and types of leachant, and their effects on the leaching concentration of heavy metals in municipal solid waste (MSW) incinerator air pollution control (APC) residue. The results indicated that for extraction with distilled water, the heavy metal leaching concentration (mg/l) decreased with L/S ratio, but the amount of heavy metal released (AHMR), defined as the leached amount of heavy metals to the weight of the tested sample (mg/kg), increased with an increase in L/S ratio, in the range of 2-100. The results also showed that both the leaching concentration and the amount of released metals were strongly pH-dependent in the TCLP and modified TCLP tests. In the case of pHs lower than 6.5, the leaching concentrations of Cd, Pb, Cu, Zn, and Cr decreased with an increase in pH. As pH increased higher than 6.5, Cr and Zn were almost insoluble. Meanwhile, Cd and Cu also showed a similar trend but at pHs of 8.5 and 7.5, respectively. Due to the nature of amphoteric elements, in the case of pHs higher than 7, the Pb leaching concentration increased with increasing pH. In modified TCLP tests with the pH value controlled at the same level as in the SCE test, the heavy metal speciation approached the extractable carbonate bound fraction by the SCE. Both amounts of targeted metals leached from the SCE and modified TCLP tests were much higher than those for the regular TCLP and water extraction tests.

Geochemical characteristics of Au in the water systemfrom abandoned gold mines area

NASA Astrophysics Data System (ADS)

Cho, Kanghee; Kim, Bongju; Kim, Byungjoo; Park, Cheonyoung; Choi, Nagchoul

2013-04-01

The AMD (acid mine drainage) poses a threat not only to the aquatic life in mountain streams and rivers, but can also contaminate groundwater and downstream water bodies. Besides pyrite, sulfides of copper, zinc, cadmium, lead and arsenic in the drainage tunnels and tailings piles also undergo similar geochemical reactions, releasing toxic metals and more H+ into the mine drainage. The fate of gold in the AMD system is reduced and precipitated with iron oxides by oxidation-reduction reaction between ferrous/ferric iron and Au3+/Au0. The objective of this study was to investigate the influence of the transport characteristic on the distance through distribution of heavy metals and gold on the interrelation between acid mine drainage and sediments in the abandoned Gwang-yang gold mine, Korea. We conducted to confirm the chemical (chemical analysis and sequential extraction) and mineralogical property (XRD, SEM-EDS and polarization microscope) from AMD, sediments and tailing samples. The result of chemical analysis showed that Fe contents in the AMD and sediments from the upstream to the downstream ranged of 10.99 to 18.60 mg/L and 478.74 to 542.98 mg/kg, respectively. Also the contents of Au and As in the sediment were respectively ranged from 14.06 to 22.85 g/t and 0.245 to 0.612 mg/kg. In XRD analysis of the sediments, x-ray diffracted d-value belong to quartz, geothite was observed. The results of SEM-EDS analysis revealed that iron hydroxide were observed in the sediment and tailing. The result of sequential extraction for Au from the sediment showed that Au predominated in 26 to 27% of Organic matter fraction(STEP 4), and 24 to 25% of Residual fraction(STEP 5).

Immobilization of uranium in contaminated soil by natural apatite addition

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

Mrdakovic Popic, Jelena; Stojanovic, Mirjana; Milosevic, Sinisa

2007-07-01

Available in abstract form only. Full text of publication follows: The goal of this study was to evaluate the effectiveness of Serbian natural mineral apatite as soil additive for reducing the migration of uranium from contaminated sediments. In laboratory study we investigated the sorption properties of domestic apatite upon different experimental conditions, such as pH, adsorbent mass, reaction period, concentration of P{sub 2}O{sub 5} in apatite, solid/liquid ratio. In second part of study, we did the quantification of uranium in soil samples, taken from uranium mine site 'Kalna', by sequential extraction method. The same procedure was, also, used for uraniummore » determination in contaminated soil samples after apatite addition, in order to determine the changes in U distribution in soil fraction. The obtained results showed the significant level of immobilization (96.7%) upon certain conditions. Increase of %P{sub 2}O{sub 5} in apatite and process of mechano-chemical activation led to increase of immobilization capacity from 17.50% till 91.64%. The best results for uranium binding were obtained at pH 5.5 and reaction period 60 days (98.04%) The sequential extraction showed the presence of uranium (48.2%) in potentially available soil fractions, but with the apatite addition uranium content in these fractions decreased (30.64%), what is considering environmental aspect significant fact. In situ immobilization of radionuclide using inexpensive sequestering agents, such as apatite, is very adequate for big contaminated areas of soil with low level of contamination. This investigation study on natural apatite from deposit 'Lisina' Serbia was the first one of this type in our country. Key words: apatite, uranium, immobilization, soil, contamination. (authors)« less

The added value of mifepristone to non-surgical treatment regimens for uterine evacuation in case of early pregnancy failure: a systematic review of the literature.

PubMed

van den Berg, Joyce; Gordon, Bernardus B M; Snijders, Marcus P M L; Vandenbussche, Frank P H A; Coppus, Sjors F P J

2015-12-01

Early pregnancy failure (EPF) is a common complication of pregnancy. Surgical intervention carries a risk of complications and, therefore, medical treatment appears to be a safe alternative. Unfortunately, the current medical treatment with misoprostol alone has complete evacuation rates between 53% and 87%. Some reports suggest that sequential treatment with mifepristone and misoprostol leads to higher success rates than misoprostol alone. To evaluate the added value of mifepristone to current non-surgical treatment regimens in women with EPF we performed a systematic literature search. Electronic databases were searched: PubMed, Cochrane Library, Current Controlled Trials, and ClinicalTrials.gov. Clinical studies, both randomised and non-randomised trials, reporting on the added value of mifepristone to current non-surgical treatment regimens in women with EPF were included. Data of sixteen studies were extracted using a data extraction sheet (based on the Cochrane Consumers and Communication Review Group's data extraction template). The methodological quality was assessed using the Cochrane Collaboration Risk of Bias tool. In five randomised and eleven non-randomised trials, success rates of sequential treatment with mifepristone and misoprostol in case of EPF varied between 52% and 95%. Large heterogeneity existed in treatment regimens and comparators between studies. The existing evidence is insufficient to draw firm conclusions about the added value of mifepristone to misoprostol alone. A sufficiently powered randomised, double blinded placebo-controlled trial is urgently required to test whether, in EPF, the sequential combination of mifepristone with misoprostol is superior to misoprostol only. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Targeting intensive versus conventional glycaemic control for type 1 diabetes mellitus: a systematic review with meta-analyses and trial sequential analyses of randomised clinical trials

PubMed Central

Kähler, Pernille; Grevstad, Berit; Almdal, Thomas; Gluud, Christian; Wetterslev, Jørn; Vaag, Allan; Hemmingsen, Bianca

2014-01-01

Objective To assess the benefits and harms of targeting intensive versus conventional glycaemic control in patients with type 1 diabetes mellitus. Design A systematic review with meta-analyses and trial sequential analyses of randomised clinical trials. Data sources The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded and LILACS to January 2013. Study selection Randomised clinical trials that prespecified different targets of glycaemic control in participants at any age with type 1 diabetes mellitus were included. Data extraction Two authors independently assessed studies for inclusion and extracted data. Results 18 randomised clinical trials included 2254 participants with type 1 diabetes mellitus. All trials had high risk of bias. There was no statistically significant effect of targeting intensive glycaemic control on all-cause mortality (risk ratio 1.16, 95% CI 0.65 to 2.08) or cardiovascular mortality (0.49, 0.19 to 1.24). Targeting intensive glycaemic control reduced the relative risks for the composite macrovascular outcome (0.63, 0.41 to 0.96; p=0.03), and nephropathy (0.37, 0.27 to 0.50; p<0.00001. The effect estimates of retinopathy, ketoacidosis and retinal photocoagulation were not consistently statistically significant between random and fixed effects models. The risk of severe hypoglycaemia was significantly increased with intensive glycaemic targets (1.40, 1.01 to 1.94). Trial sequential analyses showed that the amount of data needed to demonstrate a relative risk reduction of 10% were, in general, inadequate. Conclusions There was no significant effect towards improved all-cause mortality when targeting intensive glycaemic control compared with conventional glycaemic control. However, there may be beneficial effects of targeting intensive glycaemic control on the composite macrovascular outcome and on nephropathy, and detrimental effects on severe hypoglycaemia. Notably, the data for retinopathy and ketoacidosis were inconsistent. There was a severe lack of reporting on patient relevant outcomes, and all trials had poor bias control. PMID:25138801

Better together: reduced compliance after sequential versus simultaneous bilateral hearing aids fitting.

PubMed

Lavie, Limor; Banai, Karen; Attias, Joseph; Karni, Avi

2014-03-01

The purpose of this study was to determine the effects of sequential versus simultaneous bilateral hearing aids fitting on patient compliance. Thirty-six older adults with hearing impairment participated in this study. Twelve were fitted with bilateral hearing aids simultaneously. The remaining participants were fitted sequentially: One hearing aid (to the left or to the right ear) was used initially; 1 month later, the other ear was also fitted with a hearing aid for bilateral use. Self-reports on usefulness and compliance were elicited after the first and second months of hearing aid use. In addition, the number of hours the hearing aids were used was extracted from the data loggings of each device. Simultaneous fitting resulted in high levels of compliance and consistent usage throughout the study period. Sequential fitting resulted in abrupt reduction in compliance and hours of use once the second hearing aid was added, both in the clinical scoring and in the data loggings. Simultaneous fitting of bilateral hearing aids results in better compliance compared with sequential fitting. The addition of a second hearing aid after a relatively short period of monaural use may lead to inconsistent use of both hearing aids.

Cloning and characterization of an 11S legumin, Car i 4, a major allergen in pecan.

PubMed

Sharma, Girdhari M; Irsigler, Andre; Dhanarajan, Pushparani; Ayuso, Rosalia; Bardina, Luda; Sampson, Hugh A; Roux, Kenneth H; Sathe, Shridhar K

2011-09-14

Among tree nut allergens, pecan allergens remain to be identified and characterized. The objective was to demonstrate the IgE-binding ability of pecan 11S legumin and characterize its sequential IgE-binding epitopes. The 11S legumin gene was amplified from a pecan cDNA library and expressed as a fusion protein in Escherichia coli. The native 11S legumin in pecan extract was identified by mass spectrometry/mass spectrometry (MS/MS). Sequential epitopes were determined by probing the overlapping peptides with three serum pools prepared from different patients' sera. A three-dimensional model was generated using almond legumin as a template and compared with known sequential epitopes on other allergenic tree nut homologues. Of 28 patients tested by dot blot, 16 (57%) bound to 11S legumin, designated Car i 4. MS/MS sequencing of native 11S legumin identified 33 kDa acidic and 20-22 kDa basic subunits. Both pecan and walnut seed protein extracts inhibited IgE binding to recombinant Car i 4, suggesting cross-reactivity with Jug r 4. Sequential epitope mapping results of Car i 4 revealed weak, moderate, and strong reactivity of serum pools against 10, 5, and 4 peptides, respectively. Seven peptides were recognized by all three serum pools, of which two were strongly reactive. The strongly reactive peptides were located in three discrete regions of the Car i 4 acidic subunit sequence (residues 118-132, 208-219, and 238-249). Homology modeling of Car i 4 revealed significant overlapping regions shared in common with other tree nut legumins.

OPTIMIZING NIST SEQUENTIAL EXTRACTION METHOD FOR LAKE SEDIMENT (SRM4354)

EPA Science Inventory

Traditionally, measurements of radionuclides in the environment have focused on the determination of total concentration. It is clear, however, that total concentration does not describe the bioavailability of contaminating radionuclides. The environmental behavior depends on spe...

Assessing Metal Mobilization from Industrially Lead-Contaminated Soils Located at an Urban Site

EPA Science Inventory

A series of leaching and partitioning tests (Toxicity Characteristic Leaching Procedure (TCLP), Synthetic Precipitation Leaching Procedure (SPLP), Controlled Acidity Leaching Protocol (CALP), Acid Neutralization Capacity (ANC), and sequential extraction) were applied to three dif...

The promotion of hair regrowth by topical application of a Perilla frutescens extract through increased cell viability and antagonism of testosterone and dihydrotestosterone.

PubMed

Li, Jing-Jie; Li, Zheng; Gu, Li-Juan; Choi, Kang-Ju; Kim, Dong-Seon; Kim, Ho-Kyoung; Sung, Chang-Keun

2018-01-01

This study investigated the potential hair regrowth effects associated with a plant extract of Perilla frutescens, which was selected due to its putative hair regrowth activity. Extracts were prepared from dried P. frutescens suspended in distilled water, where the resultant aqueous suspension was fractionated sequentially using hexane, ethyl acetate, n-butanol, and distilled water. We observed that the n-butanol fraction resulted in the highest hair regrowth activity. The n-butanol soluble fraction of P. frutescens extract (BFPE) was further separated using AB-8 macroporous resin and silica gel chromatography to obtain rosmarinic acid (RA), which demonstrated effective hair growth regeneration potential. BFPE also showed in vivo anti-androgenic activity following the use of a hair growth assay in testosterone-sensitive male C57Bl/6NCrSlc mice. Furthermore, the effects of cell viability promotion were investigated following an in vitro analysis in primary hair follicle fibroblast cells (PHFCs) treated with RA. The results suggested that RA was the active compound in P. frutescens that triggers hair growth, and RA could be a potential therapeutic agent for the promotion of hair growth and prevention of androgenetic alopecia (AGA).

Rare earth elements mobility processes in an AMD-affected estuary: Huelva Estuary (SW Spain).

PubMed

Lecomte, K L; Sarmiento, A M; Borrego, J; Nieto, J M

2017-08-15

Huelva Estuary is a transition zone where REE-rich acidic waters interact with saline-alkaline seawater. This mixing process influences the geochemical and mineralogical characteristics of particulate and dissolved fractions. The Tinto River has >11,000μgL -1 dissolved REE (pH=1.66), whereas seawater only reaches 8.75·10 -2 μgL -1 dissolved REE (pH=7.87). REE-normalized patterns in "pH<6 solutions" are parallel and show similarities, diminishing their concentration as pH increases. Sequential extraction performed on the generated precipitates of mixed solutions indicates that most REE are associated to the residual phase. In a second order, REE are associated with soluble salts at pH3 and 3.5 whereas in sediments generated at pH4 and 5, they are distributed in salts (1° extraction), poorly crystallized Fe-bearing minerals (schwertmannite, 3° extraction) and well crystallized Fe-bearing minerals (goethite - hematite, 4° extraction). Finally, precipitated REE are highest at pH6 newly formed minerals with a release to solution in higher pH. Copyright © 2017 Elsevier Ltd. All rights reserved.

Production of Recombinant Trichoderma reesei Cellobiohydrolase II in a New Expression System Based on Wickerhamomyces anomalus

PubMed Central

Díaz-Rincón, Dennis J.; Duque, Ivonne; Osorio, Erika; Rodríguez-López, Alexander; Espejo-Mojica, Angela; Parra-Giraldo, Claudia M.

2017-01-01

Cellulase is a family of at least three groups of enzymes that participate in the sequential hydrolysis of cellulose. Recombinant expression of cellulases might allow reducing their production times and increasing the low proteins concentrations obtained with filamentous fungi. In this study, we describe the production of Trichoderma reesei cellobiohydrolase II (CBHII) in a native strain of Wickerhamomyces anomalus. Recombinant CBHII was expressed in W. anomalus 54-A reaching enzyme activity values of up to 14.5 U L−1. The enzyme extract showed optimum pH and temperature of 5.0–6.0 and 40°C, respectively. Enzyme kinetic parameters (KM of 2.73 mM and Vmax of 23.1 µM min−1) were between the ranges of values reported for other CBHII enzymes. Finally, the results showed that an enzymatic extract of W. anomalus 54-A carrying the recombinant T. reesei CBHII allows production of reducing sugars similar to that of a crude extract from cellulolytic fungi. These results show the first report on the use of W. anomalus as a host to produce recombinant proteins. In addition, recombinant T. reesei CBHII enzyme could potentially be used in the degradation of lignocellulosic residues to produce bioethanol, based on its pH and temperature activity profile. PMID:28951785

Speciations of trace metals in the Danube alluvial sediments within an oil refinery.

PubMed

Relić, Dubravka; Dordević, Dragana; Popović, Aleksandar; Blagojević, Tamara

2005-07-01

A sequential extraction procedure was applied to identify forms of Ni, Zn, Pb and Cu with Fe- and Mn-oxides associated in alluvial sediments of the River Danube within Pancevo Oil Refinery (Serbia). The five steps of the sequential extraction procedure partitioned metals into: CH(3)COONH(4) extractable (S1); NH(2)OH.HCl carbonate extractable and easily reducible (S2); (NH(4))(2)C(2)O(2)/H(2)C(2)O(2) moderately reducible (S3); H(2)O(2)-HNO(3) organic extractable (S4); and HCl acid soluble residue (S5). Extracted concentrations of trace metals, analyzed after all five steps, were found to be (mg kg(-1)) for Mn: 656, Fe: 26734, Ni: 32.3, Zn: 72.8, Pb: 13.4 and Cu: 27.0. Most of the elements were found in acid soluble residue, characterizing stable compounds in sediments. Non-residual fractions of trace metals (sum of the first four fractions) were analyzed because they are more bioavailable than the residual amount. Correlation analysis and two multivariate analysis methods (principal component and cluster analysis) were used to understand and visualize the associations between the non-residual fractions of trace metals and certain forms, more or less crystalline of Fe- and Mn-oxides within the analyzed sediments, since Fe- and Mn-oxides play an important role in trace metal sorption within aquatic systems, especially within the Danube alluvium where the fluctuations of groundwater are very frequent and the level of groundwater could come close to surface.

Sequential Extraction Results in Improved Proteome Profiling of Medicinal Plant Pinellia ternata Tubers, Which Contain Large Amounts of High-Abundance Proteins

PubMed Central

An, SuFang; Gong, FangPing; Wang, Wei

2012-01-01

Pinellia ternata tuber is one of the well-known Chinese traditional medicines. In order to understand the pharmacological properties of tuber proteins, it is necessary to perform proteome analysis of P. ternata tubers. However, a few high-abundance proteins (HAPs), mainly mannose-binding lectin (agglutinin), exist in aggregates of various sizes in the tubers and seriously interfere with proteome profiling by two-dimensional electrophoresis (2-DE). Therefore, selective depletion of these HAPs is a prerequisite for enhanced proteome analysis of P. ternata tubers. Based on differential protein solubility, we developed a novel protocol involving two sequential extractions for depletion of some HAPs and prefractionation of tuber proteins prior to 2-DE. The first extraction using 10% acetic acid selectively extracted acid-soluble HAPs and the second extraction using the SDS-containing buffer extracted remaining acid-insoluble proteins. After application of the protocol, 2-DE profiles of P. ternata tuber proteins were greatly improved and more protein spots were detected, especially low-abundance proteins. Moreover, the subunit composition of P. ternata lectin was analyzed by electrophoresis. Native lectin consists of two hydrogen-bonded subunits (11 kDa and 25 kDa) and the 11 kDa subunit was a glycoprotein. Subsequently, major HAPs in the tubers were analyzed by mass spectrometry, with nine protein spots being identified as lectin isoforms. The methodology was easy to perform and required no specialized apparatus. It would be useful for proteome analysis of other tuber plants of Araceae. PMID:23185632

Sequential extraction results in improved proteome profiling of medicinal plant Pinellia ternata tubers, which contain large amounts of high-abundance proteins.

PubMed

Wu, Xiaolin; Xiong, Erhui; An, Sufang; Gong, Fangping; Wang, Wei

2012-01-01

Pinellia ternata tuber is one of the well-known Chinese traditional medicines. In order to understand the pharmacological properties of tuber proteins, it is necessary to perform proteome analysis of P. ternata tubers. However, a few high-abundance proteins (HAPs), mainly mannose-binding lectin (agglutinin), exist in aggregates of various sizes in the tubers and seriously interfere with proteome profiling by two-dimensional electrophoresis (2-DE). Therefore, selective depletion of these HAPs is a prerequisite for enhanced proteome analysis of P. ternata tubers. Based on differential protein solubility, we developed a novel protocol involving two sequential extractions for depletion of some HAPs and prefractionation of tuber proteins prior to 2-DE. The first extraction using 10% acetic acid selectively extracted acid-soluble HAPs and the second extraction using the SDS-containing buffer extracted remaining acid-insoluble proteins. After application of the protocol, 2-DE profiles of P. ternata tuber proteins were greatly improved and more protein spots were detected, especially low-abundance proteins. Moreover, the subunit composition of P. ternata lectin was analyzed by electrophoresis. Native lectin consists of two hydrogen-bonded subunits (11 kDa and 25 kDa) and the 11 kDa subunit was a glycoprotein. Subsequently, major HAPs in the tubers were analyzed by mass spectrometry, with nine protein spots being identified as lectin isoforms. The methodology was easy to perform and required no specialized apparatus. It would be useful for proteome analysis of other tuber plants of Araceae.

The removal of heavy metals from contaminated soil by a combination of sulfidisation and flotation.

PubMed

Vanthuyne, Mathias; Maes, André

2002-05-06

The possibility of removing cadmium, copper, lead and zinc from Belgian loamy soil by a combination of sulfidisation pre-treatment and Denver flotation was investigated. The potentially available--sulfide convertible--metal content of the metal polluted soil was estimated by EDTA (0.1 M, pH 4.65) extraction and BCR sequential extraction. EDTA extraction is better at approximating the metal percentage that is expected to be convertible into a metal sulfide phase, in contrast to the sequential extraction procedure of 'Int. J. Environ. Anal. Chem. 51 (1993) pp. 135-151' in which transition metals present as iron oxide co-precipitates are dissolved by hydroxylammoniumchloride in the second extraction step. To compare the surface characteristics of metal sulfides formed by sulfidisation with those of crystalline metal sulfides, two types of synthetic sediments were prepared and extracted with 0.1 M EDTA (pH 4.65) in anoxic conditions. Separate metal sulfides or co-precipitates with iron sulfide were formed by sulfide conditioning. The Denver flotation of both types of synthetic sediments (kerosene as collector at high background electrolyte concentrations) resulted in similar concentrating factors for freshly formed metal sulfides as for fine-grained crystalline metal sulfides. The selective flotation of metal sulfides after sulfide conditioning of a polluted soil, using kerosene or potassium ethyl xanthate as collectors and MIBC as frother, was studied at high background electrolyte concentrations. The sulfidisations were made in ambient air and inside an anoxic glove box. The concentrating factors corrected by the potentially available metal percentage, determined by 0.1 M EDTA extraction, lie between 2 and 3. The selective flotation of these finely dispersed, amorphous, metal sulfides can possibly be improved by optimising the bubble-particle interaction.

Asymptotic Properties of the Sequential Empirical ROC, PPV and NPV Curves Under Case-Control Sampling.

PubMed

Koopmeiners, Joseph S; Feng, Ziding

2011-01-01

The receiver operating characteristic (ROC) curve, the positive predictive value (PPV) curve and the negative predictive value (NPV) curve are three measures of performance for a continuous diagnostic biomarker. The ROC, PPV and NPV curves are often estimated empirically to avoid assumptions about the distributional form of the biomarkers. Recently, there has been a push to incorporate group sequential methods into the design of diagnostic biomarker studies. A thorough understanding of the asymptotic properties of the sequential empirical ROC, PPV and NPV curves will provide more flexibility when designing group sequential diagnostic biomarker studies. In this paper we derive asymptotic theory for the sequential empirical ROC, PPV and NPV curves under case-control sampling using sequential empirical process theory. We show that the sequential empirical ROC, PPV and NPV curves converge to the sum of independent Kiefer processes and show how these results can be used to derive asymptotic results for summaries of the sequential empirical ROC, PPV and NPV curves.

Asymptotic Properties of the Sequential Empirical ROC, PPV and NPV Curves Under Case-Control Sampling

PubMed Central

Koopmeiners, Joseph S.; Feng, Ziding

2013-01-01

The receiver operating characteristic (ROC) curve, the positive predictive value (PPV) curve and the negative predictive value (NPV) curve are three measures of performance for a continuous diagnostic biomarker. The ROC, PPV and NPV curves are often estimated empirically to avoid assumptions about the distributional form of the biomarkers. Recently, there has been a push to incorporate group sequential methods into the design of diagnostic biomarker studies. A thorough understanding of the asymptotic properties of the sequential empirical ROC, PPV and NPV curves will provide more flexibility when designing group sequential diagnostic biomarker studies. In this paper we derive asymptotic theory for the sequential empirical ROC, PPV and NPV curves under case-control sampling using sequential empirical process theory. We show that the sequential empirical ROC, PPV and NPV curves converge to the sum of independent Kiefer processes and show how these results can be used to derive asymptotic results for summaries of the sequential empirical ROC, PPV and NPV curves. PMID:24039313

Isolation and characterization of antimicrobial constituents of Searsia chirindensis L. (Anacardiaceae) leaf extracts.

PubMed

Madikizela, Balungile; Aderogba, Mutalib A; Van Staden, Johannes

2013-11-25

Searsia chirindensis is used in South African traditional medicine for management of bacterial infections such as diarrhoea. Aim of the study was to examine the phytochemical composition from the leaves of Searsia chirindensis that is responsible for the ethnomedicinal use of this plant. The crude extract (80% methanol) was extracted sequentially with dichloromethane (DCM), ethyl acetate (EtOAc) and n-butanol. The extracts and isolated compounds were tested for their antibacterial activity against Gram-negative (Campylobacter jejuni, Escherichia coli and Shigella flexneri) and Gram-positive (Staphylococcus aureus) bacterial strains using the microdilution method. Bioguided fractionation of EtOAc fraction afforded five phenolic compounds. Structural elucidation was carried out using NMR (1D and 2D) spectroscopic analyses. Of the three fractions obtained from the crude extract, EtOAc was the most active and its fractionation afforded methyl gallate (1), and four flavonol glycosides: myricetin-3-O-arabinopyranoside (2), myricetrin-3-O-rhamnoside (3), kaempferol-3-O-rhamnoside (4) and quercetin-3-O-arabinofuranoside (5). These compounds are reported from Searsia chirindensis for the first time. All the compounds showed good antibacterial activity against all bacterial strains tested. Their minimum inhibitory concentrations ranged from 30 to 250 µg/mL. Antibacterial activity demonstrated by the extracts and isolated compounds provides credence to the ethnomedicinal use of Searsia chirindensis against diarrhoea. © 2013 Elsevier Ireland Ltd. All rights reserved.

Lineup composition, suspect position, and the sequential lineup advantage.

PubMed

Carlson, Curt A; Gronlund, Scott D; Clark, Steven E

2008-06-01

N. M. Steblay, J. Dysart, S. Fulero, and R. C. L. Lindsay (2001) argued that sequential lineups reduce the likelihood of mistaken eyewitness identification. Experiment 1 replicated the design of R. C. L. Lindsay and G. L. Wells (1985), the first study to show the sequential lineup advantage. However, the innocent suspect was chosen at a lower rate in the simultaneous lineup, and no sequential lineup advantage was found. This led the authors to hypothesize that protection from a sequential lineup might emerge only when an innocent suspect stands out from the other lineup members. In Experiment 2, participants viewed a simultaneous or sequential lineup with either the guilty suspect or 1 of 3 innocent suspects. Lineup fairness was varied to influence the degree to which a suspect stood out. A sequential lineup advantage was found only for the unfair lineups. Additional analyses of suspect position in the sequential lineups showed an increase in the diagnosticity of suspect identifications as the suspect was placed later in the sequential lineup. These results suggest that the sequential lineup advantage is dependent on lineup composition and suspect position. (c) 2008 APA, all rights reserved

Sequential state discrimination and requirement of quantum dissonance

NASA Astrophysics Data System (ADS)

Pang, Chao-Qian; Zhang, Fu-Lin; Xu, Li-Fang; Liang, Mai-Lin; Chen, Jing-Ling

2013-11-01

We study the procedure for sequential unambiguous state discrimination. A qubit is prepared in one of two possible states and measured by two observers Bob and Charlie sequentially. A necessary condition for the state to be unambiguously discriminated by Charlie is the absence of entanglement between the principal qubit, prepared by Alice, and Bob's auxiliary system. In general, the procedure for both Bob and Charlie to recognize between two nonorthogonal states conclusively relies on the availability of quantum discord which is precisely the quantum dissonance when the entanglement is absent. In Bob's measurement, the left discord is positively correlated with the information extracted by Bob, and the right discord enhances the information left to Charlie. When their product achieves its maximum the probability for both Bob and Charlie to identify the state achieves its optimal value.

Antiplasmodial activity of extracts of Tridax procumbens and Phyllanthus amarus in in vitro Plasmodium falciparum culture systems.

PubMed

Appiah-Opong, R; Nyarko, A K; Dodoo, D; Gyang, F N; Koram, K A; Ayisi, N K

2011-12-01

Aqueous extracts of Tridax procumbens (TP) (Compositae) and Phyllanthus amarus (PA) (Euphorbiaceae) are used in traditional medicine in Ghana to treat malaria. Previous studies have demonstrated the anti-trypanosoma, anti-bacterial and anti-HIV effects of TP and PA. To assess the antiplasmodial activity of extracts of TP and PA. Aqueous extracts of TP and PA were prepared. A portion of each was freeze-dried and the remaining extracted sequentially with ethyl acetate and chloroform. Ethanolic extracts were also prepared. The antiplasmodial activity of the extracts was assessed with the 3H-hypoxanthine assay using chloroquine-resistant (Dd2) Plasmodium falciparum parasites. Chloroquine was used as the reference drug. The modified tetrazolium-based colorimetric assay was also used to evaluate the red blood cell (RBC)-protective/antiplasmodial activities and cytotoxicities of the extracts. Results showed that TP and PA have antiplasmodial activities. The aqueous and ethanolic extracts of PA were the most active, yielding EC50 values of 34.9 µg/ml and 31.2 µg/ml, respectively in the tetrazolium-based assay. The TP and PA produced and IC50 values of 24.8 µg/ml and 11.7 µg/ml, respectively in the hypoxanthine assay. Protection of human RBCs against P. falciparum damage by the extracts highly correlated with their antiplasmodial activities. None of the extracts, within the concentration range (1.9-500 µg/ml) studied produced any overt toxicity to human RBCs. The results indicate that both PA and TP have activities against chloroquine-resistant P. falciparum (Dd2) parasites. The antiplasmodial principles extracted into water and ethanol but not chloroform or ethyl acetate.

Bioleaching of vanadium from barren stone coal and its effect on the transition of vanadium speciation and mineral phase

NASA Astrophysics Data System (ADS)

Wang, Xin; Lin, Hai; Dong, Ying-bo; Li, Gan-yu

2018-03-01

This study determined the optimal conditions required to obtain maximum vanadium extraction and examined the transition of mineral phases and vanadium speciation during the bioleaching process. Parameters including the initial pH value, initial Fe2+ concentration, solid load, and inoculum quantity were examined. The results revealed that 48.92wt% of the vanadium was extracted through bioleaching under optimal conditions. Comparatively, the chemical leaching yield (H2SO4, pH 2.0) showed a slower and milder increase in vanadium yield. The vanadium bioleaching yield was 35.11wt% greater than the chemical leaching yield. The Community Bureau of Reference (BCR) sequential extraction results revealed that 88.62wt% of vanadium existed in the residual fraction. The bacteria substantially changed the distribution of the vanadium speciation during the leaching process, and the residual fraction decreased to 48.44wt%. The X-ray diffraction (XRD) and Fourier transform infrared (FTIR) results provided evidence that the crystal lattice structure of muscovite was destroyed by the bacteria.

In Vitro Antimicrobial Activity of Embothrium coccineum Used as Traditional Medicine in Patagonia against Multiresistant Bacteria.

PubMed

Canales, Nicole; Montenegro, Iván; Párraga, Mario; Olguín, Yusser; Godoy, Patricio; Werner, Enrique; Madrid, Alejandro

2016-10-31

Embothrium coccineum J.R. Forst. & G. Forst is an evergreen tree that has been used as a folk remedy for the treatment of neuralgia, tooth pains, wound healing, and glandular conditions, as well as an antiseptic agent against bacterial infection. The antibacterial activities of sequential extracts (hexane, dichloromethane, ethyl acetate, and ethanol) from the leaves of E. coccineum were evaluated by means of the micro-dilution assay against six ( Escherichia coli ; Klebsiella pneumoniae ; Proteus mirabilis ; Pseudomonas aeruginosa ; Staphylococcus aureus and Streptococcus pyogenes ) multiresistant bacteria strains. Ethyl acetate extract showed the best spectra of antibacterial activity against all tested bacteria, and was analyzed by gas chromatography-mass spectrometry (GC-MS) for its composition. The results of the present work provide useful baseline information for the potential development and use of nanoparticles and/or nanofibers doped with extracts of E. coccineum in the fight against multiresistant bacteria, which would allow the validation of the traditional use of E. coccineum by native peoples of Patagonia as an antimicrobial agent in the biomedical Field.

The target-to-foils shift in simultaneous and sequential lineups.

PubMed

Clark, Steven E; Davey, Sherrie L

2005-04-01

A theoretical cornerstone in eyewitness identification research is the proposition that witnesses, in making decisions from standard simultaneous lineups, make relative judgments. The present research considers two sources of support for this proposal. An experiment by G. L. Wells (1993) showed that if the target is removed from a lineup, witnesses shift their responses to pick foils, rather than rejecting the lineups, a result we will term a target-to-foils shift. Additional empirical support is provided by results from sequential lineups which typically show higher accuracy than simultaneous lineups, presumably because of a decrease in the use of relative judgments in making identification decisions. The combination of these two lines of research suggests that the target-to-foils shift should be reduced in sequential lineups relative to simultaneous lineups. Results of two experiments showed an overall advantage for sequential lineups, but also showed a target-to-foils shift equal in size for simultaneous and sequential lineups. Additional analyses indicated that the target-to-foils shift in sequential lineups was moderated in part by an order effect and was produced with (Experiment 2) or without (Experiment 1) a shift in decision criterion. This complex pattern of results suggests that more work is needed to understand the processes which underlie decisions in simultaneous and sequential lineups.

The respective effects of soil heavy metal fractions by sequential extraction procedure and soil properties on the accumulation of heavy metals in rice grains and brassicas.

PubMed

Xiao, Ling; Guan, Dongsheng; Peart, M R; Chen, Yujuan; Li, Qiqi

2017-01-01

This study was carried out to examine heavy metal accumulation in rice grains and brassicas and to identify the different controls, such as soil properties and soil heavy metal fractions obtained by the Community Bureau of Reference (BCR) sequential extraction, in their accumulation. In Guangdong Province, South China, rice grain and brassica samples, along with their rhizospheric soil, were collected from fields on the basis of distance downstream from electroplating factories, whose wastewater was used for irrigation. The results showed that long-term irrigation using the electroplating effluent has not only enriched the rhizospheric soil with Cd, Cr, Cu, and Zn but has also increased their mobility and bioavailability. The average concentrations of Cd and Cr in rice grains and brassicas from closest to the electroplating factories were significantly higher than those from the control areas. Results from hybrid redundancy analysis (hRDA) and redundancy analysis (RDA) showed that the BCR fractions of soil heavy metals could explain 29.0 and 46.5 % of total eigenvalue for heavy metal concentrations in rice grains and brassicas, respectively, while soil properties could only explain 11.1 and 33.4 %, respectively. This indicated that heavy metal fractions exerted more control upon their concentrations in rice grains and brassicas than soil properties. In terms of metal interaction, an increase of residual Zn in paddy soil or a decrease of acid soluble Cd in the brassica soil could enhance the accumulation of Cd, Cu, Cr, and Pb in both rice grains and brassicas, respectively, while the reducible or oxidizable Cd in soil could enhance the plants' accumulation of Cr and Pb. The RDA showed an inhibition effect of sand content and CFO on the accumulation of heavy metals in rice grains and brassicas. Moreover, multiple stepwise linear regression could offer prediction for Cd, Cu, Cr, and Zn concentrations in the two crops by soil heavy metal fractions and soil properties.

Mercury Speciation by X-ray Absorption Fine Structure Spectroscopy and Sequential Chemical Extractions: A Comparison of Speciation Methods

USGS Publications Warehouse

Kim, C.S.; Bloom, N.S.; Rytuba, J.J.; Brown, Gordon E.

2003-01-01

Determining the chemical speciation of mercury in contaminated mining and industrial environments is essential for predicting its solubility, transport behavior, and potential bioavailability as well as for designing effective remediation strategies. In this study, two techniques for determining Hg speciation-X-ray absorption fine structure (XAFS) spectroscopy and sequential chemical extractions (SCE)-are independently applied to a set of samples with Hg concentrations ranging from 132 to 7539 mg/kg to determine if the two techniques provide comparable Hg speciation results. Generally, the proportions of insoluble HgS (cinnabar, metacinnabar) and HgSe identified by XAFS correlate well with the proportion of Hg removed in the aqua regia extraction demonstrated to remove HgS and HgSe. Statistically significant (> 10%) differences are observed however in samples containing more soluble Hg-containing phases (HgCl2, HgO, Hg3S2O 4). Such differences may be related to matrix, particle size, or crystallinity effects, which could affect the apparent solubility of Hg phases present. In more highly concentrated samples, microscopy techniques can help characterize the Hg-bearing species in complex multiphase natural samples.

Iodine speciation in coastal and inland bathing waters and seaweeds extracts using a sequential injection standard addition flow-batch method.

PubMed

Santos, Inês C; Mesquita, Raquel B R; Bordalo, Adriano A; Rangel, António O S S

2015-02-01

The present work describes the development of a sequential injection standard addition method for iodine speciation in bathing waters and seaweeds extracts without prior sample treatment. Iodine speciation was obtained by assessing the iodide and iodate content, the two inorganic forms of iodine in waters. For the determination of iodide, an iodide ion selective electrode (ISE) was used. The indirect determination of iodate was based on the spectrophotometric determination of nitrite (Griess reaction). For the iodate measurement, a mixing chamber was employed (flow batch approach) to explore the inherent efficient mixing, essential for the indirect determination of iodate. The application of the standard addition method enabled detection limits of 0.14 µM for iodide and 0.02 µM for iodate, together with the direct introduction of the target water samples, coastal and inland bathing waters. The results obtained were in agreement with those obtained by ICP-MS and a colorimetric reference procedure. Recovery tests also confirmed the accuracy of the developed method which was effectively applied to bathing waters and seaweed extracts. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparative Effects of Biochar, Slag and Ferrous-Mn Ore on Lead and Cadmium Immobilization in Soil.

PubMed

Mehmood, Sajid; Rizwan, Muhammad; Bashir, Saqib; Ditta, Allah; Aziz, Omar; Yong, Li Zhe; Dai, Zhihua; Akmal, Muhammad; Ahmed, Waqas; Adeel, Muhammad; Imtiaz, Muhammad; Tu, Shuxin

2018-02-01

A variety of remediation approaches have been applied to the heavy metals-contaminated soils, however, the immobilization of metals in co-contaminated soils still not cleared. Therefore, an incubation study was conducted to evaluate the instantaneous effects of different concentrations of biochar (BC), slag (SL) and Fe-Mn ore (FMO) on immobilization of Pb and Cd through the Toxicity Characteristic Leaching Procedure (TCLP) by following the the European Community Bureau of Reference (BCR), CaCl 2 and NH 4 NO 3 . The sequential extraction of BCR showed decrease in acid soluble fractions, while the residual proportions of Pb and Cd were enhanced with increasing concentrations of SL and BC. Addition of BC significantly lowered the extractable fractions of both metals by TCLP, NH 4 NO 3 and CaCl 2 as compared to SL and FMO. Among all amendments, BC incorporation into co-contaminated soil offered promising results for Pb and Cd immobilization. Overall, all amendments showed positive and long-term impact on the reclamation of co-contaminated soil with heavy metals and could deserve advance monitoring studies on a field scale.

Screening antimicrobial activity of various extracts of Urtica dioica.

PubMed

Modarresi-Chahardehi, Amir; Ibrahim, Darah; Fariza-Sulaiman, Shaida; Mousavi, Leila

2012-12-01

Urtica dioica or stinging nettle is traditionally used as an herbal medicine in Western Asia. The current study represents the investigation of antimicrobial activity of U. dioica from nine crude extracts that were prepared using different organic solvents, obtained from two extraction methods: the Soxhlet extractor (Method I), which included the use of four solvents with ethyl acetate and hexane, or the sequential partitions (Method II) with a five solvent system (butanol). The antibacterial and antifungal activities of crude extracts were tested against 28 bacteria, three yeast strains and seven fungal isolates by the disc diffusion and broth dilution methods. Amoxicillin was used as positive control for bacteria strains, vancomycin for Streptococcus sp., miconazole nitrate (30 microg/mL) as positive control for fungi and yeast, and pure methanol (v/v) as negative control. The disc diffusion assay was used to determine the sensitivity of the samples, whilst the broth dilution method was used for the determination of the minimal inhibition concentration (MIC). The ethyl acetate and hexane extract from extraction method I (EA I and HE I) exhibited highest inhibition against some pathogenic bacteria such as Bacillus cereus, MRSA and Vibrio parahaemolyticus. A selection of extracts that showed some activity was further tested for the MIC and minimal bactericidal concentrations (MBC). MIC values of Bacillus subtilis and Methicillin-resistant Staphylococcus aureus (MRSA) using butanol extract of extraction method II (BE II) were 8.33 and 16.33mg/mL, respectively; while the MIC value using ethyl acetate extract of extraction method II (EAE II) for Vibrio parahaemolyticus was 0.13mg/mL. Our study showed that 47.06% of extracts inhibited Gram-negative (8 out of 17), and 63.63% of extracts also inhibited Gram-positive bacteria (7 out of 11); besides, statistically the frequency of antimicrobial activity was 13.45% (35 out of 342) which in this among 21.71% belongs to antimicrobial activity extracts from extraction method I (33 out of 152 of crude extracts) and 6.82% from extraction method II (13 out of 190 of crude extracts). However, crude extracts from method I exhibited better antimicrobial activity against the Gram-positive bacteria than the Gram-negative bacteria. The positive results on medicinal plants screening for antibacterial activity constitutes primary information for further phytochemical and pharmacological studies. Therefore, the extracts could be suitable as antimicrobial agents in pharmaceutical and food industry.

Arsenic bio-accessibility and bioaccumulation in aged pesticide contaminated soils: A multiline investigation to understand environmental risk.

PubMed

Rahman, M S; Reichelt-Brushet, A J; Clark, M W; Farzana, T; Yee, L H

2017-03-01

Bio-accessibility and bioavailability of arsenic (As) in historically As-contaminated soils (cattle tick pesticide), and pristine soils were assessed using 3 different approaches. These approaches included human bio-accessibility using an extraction test replicating gastric conditions (in vitro physiologically-based extraction test); an operationally defined bioaccessibility extraction test - 1.0M HCl extraction; and a live organism bioaccumulation test using earthworms. A sequential extraction procedure revealed the soil As-pool that controls bio-accessibility and bioaccumulation of As. Findings show that As is strongly bound to historically contaminated soil with a lower degree of As bio-accessibility (<15%) and bioaccumulation (<9%) compared with freshly contaminated soil. Key to these lower degrees of bio-accessibility and bioaccumulation is the greater fraction of As associated with crystalline Fe/Al oxy-hydroxide and residual phases. The high bio-accessibility and bioaccumulation of freshly sorbed As in pristine soils were from the exchangeable and specifically sorbed As fractions. Arsenic bioaccumulation in earthworms correlates strongly with both the human bio-accessible, and the operationally defined bioavailable fractions. Hence, results suggest that indirect As bioavailability measures, such as accumulation by earthworm, can be used as complementary lines of evidence to reinforce site-wide trends in the bio-accessibility using in vitro physiologically-based extractions and/or operationally defined extraction test. Such detailed knowledge is useful for successful reclamation and management of the As contaminated soils. Copyright © 2017 Elsevier B.V. All rights reserved.

Adenylate cyclase-stimulating, bone-resorbing and B TGF-like activities in canine apocrine cell adenocarcinoma of the anal sac.

PubMed

Weir, E C; Centrella, M; Matus, R E; Brooks, M L; Wu, T; Insogna, K L

1988-12-01

Canine apocrine cell adenocarcinoma of the anal sac (APO-AS) is a spontaneously occurring tumor that causes humorally mediated hypercalcemia in 90% of cases. To further define the nature of the responsible mediator in APO-AS, we examined tumor extracts from five APO-AS and four control tumors for adenylate cyclase-stimulating activity (ACSA). All extracts from APO-AS contained potent ACSA, whereas the four control tumors did not. The ACSA extracted from one tumor demonstrated a dose response curve parallel to that of synthetic bovinePTH-(1-34) and was 80% inhibited by Nle8,18,Tyr34 bPTH-(3-34)amide at a concentration of 10(-5) M. Extracts from three APO-AS and three control tumors were also examined for in vitro bone-resorbing activity (BRA). All APO-AS contained significant BRA, stimulating resorption 1.47 to 2.13-fold over basal, whereas none of the control tumors stimulated resorption. Purification of one extract using C18 reverse-phase high pressure liquid chromatography (RP-HPLC) resulted in a single sharp peak of ACSA which was 400-fold purified compared with the initial extract. This pool also contained significant bone-resorbing activity, whereas none of the adjacent pools did. Purification of a second extract using sequential CN and C18 RP-HPLC followed by size exclusion HPLC resulted in material that was at least 10,000-fold purified, and showed co-purification of ACSA and B TGF-like activity.

Statistical optimisation of cell growth and carotenoid production by rhodotorula mucilaginosa

PubMed Central

Maldonade, Iriani R.; Rodriguez-Amaya, Delia B.; Scamparini, Adilma R. P.

2012-01-01

Sequential statistical methods were used to maximise carotenoid production by a strain of Rhodotorula mucilaginosa, isolated from the Brazilian ecosystem. Initially, a factorial 25–1 experimental design was used, and the variables were pH and the levels of glucose, yeast extract, MgSO4.7H2O and KH2PO4. The nitrogen source (yeast extract) was the most important variable in enhancing carotenoid production; MgSO4.7H2O and KH2PO4 had a negative influence. The initial pH had no significant effect on carotenoid and cell productions. We further investigated the effects of glucose and yeast extract effects, using a second-order central composite design (CCD) to optimise carotenoid production, which was adequately approximated with a full quadratic equation obtained from a two-factor-2-level design. The analysis of quadratic surfaces showed that after 5 days of cultivation at 25 °C, the maximum carotenoid concentration (745 µg l-1) was obtained with 15 g l-1 of yeast extract and 20 g l-1 of glucose. The maximum carotenoid production (152 µg g-1) was obtained with 5 g l-1 yeast extract and 10 g l-1 glucose. Carotenoid formation was more sensitive to changes in yeast extract concentration than to changes in glucose concentration. Maximum cell production was achieved with 15–17 g l-1 of yeast extract and 15–20 g l-1 of glucose. PMID:24031809

Application of EDTA decontamination on soils affected by mining activities and impact of treatment on the geochemical partition of metal contaminants.

PubMed

Xia, Wenbin; Gao, Hui; Wang, Xianhai; Zhou, Chunhua; Liu, Yunguo; Fan, Ting; Wang, Xin

2009-05-30

Two soil samples were collected at mining areas located in southern Hunan Province, China. EDTA extraction of Pb, Zn, Cu and Cd from these two tailing soils was studied using column leaching experiments. The redistributions of heavy metals (HMs) were determined using the modified BCR (Community Bureau of Reference) sequential extraction procedure, before and after EDTA extraction. The results indicated that EDTA was an effective extractant because of its strong chelating ability for various HMs. The proportions of Pb, Zn, Cu and Cd in the four fractions varied largely after EDTA extraction. The extraction efficiency of EDTA of the acid-extractable fraction (AEX) was significant in shallow soil column, while in deeper soil column, decrease of the extraction efficiency of reduced (RED), oxidizable (OX) and residual fractions (RES) was obtained, which was mainly due to the decrease of EDTA concentration.

Comparison of solution-mixed and sequentially processed P3HT: F4TCNQ films: effect of doping-induced aggregation on film morphology

DOE PAGES

Jacobs, Ian E.; Aasen, Erik W.; Oliveira, Julia L.; ...

2016-03-23

Doping polymeric semiconductors often drastically reduces the solubility of the polymer, leading to difficulties in processing doped films. Here, we compare optical, electrical, and morphological properties of P3HT films doped with F4TCNQ, both from mixed solutions and using sequential solution processing with orthogonal solvents. We demonstrate that sequential doping occurs rapidly (<1 s), and that the film doping level can be precisely controlled by varying the concentration of the doping solution. Furthermore, the choice of sequential doping solvent controls whether dopant anions are included or excluded from polymer crystallites. Atomic force microscopy (AFM) reveals that sequential doping produces significantly moremore » uniform films on the nanoscale than the mixed-solution method. In addition, we show that mixed-solution doping induces the formation of aggregates even at low doping levels, resulting in drastic changes to film morphology. Sequentially coated films show 3–15 times higher conductivities at a given doping level than solution-doped films, with sequentially doped films processed to exclude dopant anions from polymer crystallites showing the highest conductivities. In conclusion, we propose a mechanism for doping induced aggregation in which the shift of the polymer HOMO level upon aggregation couples ionization and solvation energies. To show that the methodology is widely applicable, we demonstrate that several different polymer:dopant systems can be prepared by sequential doping.« less

Comparison of solution-mixed and sequentially processed P3HT: F4TCNQ films: effect of doping-induced aggregation on film morphology

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

Jacobs, Ian E.; Aasen, Erik W.; Oliveira, Julia L.

Doping polymeric semiconductors often drastically reduces the solubility of the polymer, leading to difficulties in processing doped films. Here, we compare optical, electrical, and morphological properties of P3HT films doped with F4TCNQ, both from mixed solutions and using sequential solution processing with orthogonal solvents. We demonstrate that sequential doping occurs rapidly (<1 s), and that the film doping level can be precisely controlled by varying the concentration of the doping solution. Furthermore, the choice of sequential doping solvent controls whether dopant anions are included or excluded from polymer crystallites. Atomic force microscopy (AFM) reveals that sequential doping produces significantly moremore » uniform films on the nanoscale than the mixed-solution method. In addition, we show that mixed-solution doping induces the formation of aggregates even at low doping levels, resulting in drastic changes to film morphology. Sequentially coated films show 3–15 times higher conductivities at a given doping level than solution-doped films, with sequentially doped films processed to exclude dopant anions from polymer crystallites showing the highest conductivities. In conclusion, we propose a mechanism for doping induced aggregation in which the shift of the polymer HOMO level upon aggregation couples ionization and solvation energies. To show that the methodology is widely applicable, we demonstrate that several different polymer:dopant systems can be prepared by sequential doping.« less

Rice bran extract: an inexpensive nitrogen source for the production of 2G ethanol from sugarcane bagasse hydrolysate.

PubMed

Milessi, Thais S S; Antunes, Felipe A F; Chandel, Anuj K; Silva, Silvio S

2013-10-01

Selection of the raw material and its efficient utilization are the critical factors in economization of second generation (2G) ethanol production. Fermentation of the released sugars into ethanol by a suitable ethanol producing microorganism using cheap media ingredients is the cornerstone of the overall process. This study evaluated the potential of rice bran extract (RBE) as a cheap nitrogen source for the production of 2G ethanol by Scheffersomyces (Pichia) stipitis NRRL Y-7124 using sugarcane bagasse (SB) hemicellulosic hydrolysate. Dilute acid hydrolysis of SB showed 12.45 g/l of xylose and 0.67 g/l of glucose along with inhibitors. It was concentrated by vacuum evaporation and submitted to sequential detoxification (neutralization by calcium hydroxide and charcoal adsorption). The detoxified hydrolysate revealed the removal of furfural (81 %) and 5-hydroxymethylfurfural (61 %) leading to the final concentration of glucose (1.69 g/l) and xylose (33.03 g/l). S. stipitis was grown in three different fermentation media composed of detoxified hydrolysate as carbon source supplemented with varying nitrogen sources i.e. medium #1 (RBE + ammonium sulfate + calcium chloride), medium #2 (yeast extract + peptone) and medium #3 (yeast extract + peptone + malt extract). Medium #1 showed maximum ethanol production (8.6 g/l, yield 0.22 g/g) followed by medium #2 (8.1 g/l, yield 0.19 g/g) and medium #3 (7.4 g/l, yield 0.18 g/g).

Chemical and physiological metal bioaccessibility assessment in surface bottom sediments from the Deba River urban catchment: Harmonization of PBET, TCLP and BCR sequential extraction methods.

PubMed

Unda-Calvo, Jessica; Martínez-Santos, Miren; Ruiz-Romera, Estilita

2017-04-01

In the present study, the physiologically based extraction test PBET (gastric and intestinal phases) and two chemical based extraction methods, the toxicity characteristic leaching procedure (TCLP) and the sequential extraction procedure BCR 701 (Community Bureau of Reference of the European Commission) have been used to estimate and evaluate the bioaccessibility of metals (Fe, Mn, Zn, Cu, Ni, Cr and Pb) in sediments from the Deba River urban catchment. The statistical analysis of data and comparison among physiological and chemical methods have highlighted the relevance of simulate the gastrointestinal tract environment since metal bioaccessibility seems to depend on water and sediment properties such as pH, redox potential and organic matter content, and, primordially, on the form in which metals are present in the sediment. Indeed, metals distributed among all fractions (Mn, Ni, Zn) were the most bioaccessible, followed by those predominantly bound to oxidizable fraction (Cu, Cr and Pb), especially near major urban areas. Finally, a toxicological risk assessment was also performed by determining the hazard quotient (HQ), which demonstrated that, although sediments from mid- and downstream sampling points presented the highest metal bioaccessibilities, were not enough to have adverse effects on human health, Cr being the most potentially toxic element. Copyright © 2017 Elsevier Inc. All rights reserved.

Extraction and speciation of arsenic in lacustrine sediments

USGS Publications Warehouse

Ficklin, W.H.

1990-01-01

Arsenic was partially extracted with 4.OM hydrochloric acid, from samples collected at 25-cm intervals in a 350-cm column of sediment at Milltown Reservoir, Montana and from a 60-cm core of sediment collected at the Cheyenne River Embayment of Lake Oahe, South Dakota. The sediment in both reservoirs is highly contaminated with arsenic. The extracted arsenic was separated into As(III) and As(V) on acetate form Dowex 1-X8 ion-exchange resin with 0.12M HCl eluent. Residual arsenic was sequentially extracted with KClO3 and HCl. Arsenic was determined by graphite-furnace atomic-absorption spectrometry. The analytical results define oxidized and reduced zones in the sediment columns. ?? 1990.

Fractionation and ecotoxicological implication of potentially toxic metals in sediments of three urban rivers and the Lagos Lagoon, Nigeria, West Africa.

PubMed

Oyeyiola, Aderonke O; Davidson, Christine M; Olayinka, Kehinde O; Alo, Babajide I

2014-11-01

The potential environmental impact of sediment-bound Cd, Cr, Cu, Pb and Zn in three trans-urban rivers in Lagos state and in the Lagos Lagoon was assessed by use of the modified Community Bureau of Reference (BCR) sequential extraction. The quality of the data was checked using BCR CRM 143R and BCR CRM 701. Good agreement was obtained between found and certified/indicative values. Of the rivers, the Odo-Iyaalaro, was generally the most contaminated and the Ibeshe the least. Higher concentrations of metals were generally found in the dry season compared to the wet season. Cadmium and Zn were released mostly in the acid exchangeable step of the sequential extraction, indicating that they have the greatest potential mobility and bioavailability of the analytes studied. Chromium and Cu were associated mainly with the reducible and oxidisable fractions, and Pb predominantly with the reducible and residual fractions. Sediments with the highest pseudototal analyte concentrations also released higher proportions of analytes earlier in the sequential extraction procedure. The study suggests that, during the dry season, potentially toxic metals (PTM) may accumulate in sediments in relatively labile forms that are released and can potentially be transported or bioaccumulate in the rainy season. Application of risk assessment codes and Hankanson potential risk indices indicated that Cd was the element of greatest concern in the Lagos Lagoon system. The study indicated that there is a need to strengthen environmental management and pollution control measures to reduce risk from PTM, but that even relatively simple strategies, such as seasonal restrictions on dredging and fishing, could be beneficial.

Assessment of a sequential extraction protocol by examining solution chemistry and mineralogical evolution

NASA Astrophysics Data System (ADS)

Maubec, Nicolas; Pauwels, Hélène; Noël, Hervé; Bourrat, Xavier

2015-04-01

Knowledge of the behavior of heavy metals, such as copper and zinc in sediments, is a key factor to improve the management of rivers. The mobility of these metals, which may be harmful to the environment, depends directly on their concentration and speciation , which in turn depend on physico-chemical parameters such as mineralogy of the sediment fraction, pH, redox potential, salinity etc ... (Anderson et al., 2000; Sterckeman et al., 2004; Van Oort et al., 2008). Several methods based on chemical extractions are currently applied to assess the behavior of heavy metals in soils and sediments. Among them, sequential extraction procedure is widely used in soil and sediment science and provides details about the origin, biological and physicochemical availability, mobilization and transports of trace metals elements. It is based on the use of a series of extracting reagents to extract selectively heavy metals according to their association within the solid phase (Cornu and Clozel, 2000) including the following different fraction : exchangeable, bound to carbonates, associated to oxides (reducible fraction), linked to organic matter and sulfides (oxidizable fraction) as well as silicate minerals so called residual fraction (Hickey and Kittrick, 1984; Tessier et al., 1979). Consequently sequential extraction method is expected to simulate a lot of potential natural and anthropogenic modifications of environmental conditions (Arey et al., 1999; Brannon and Patrick, 1987; Hickey and Kittrick, 1984; La Force et al., 1999; Tessier et al., 1979). For three decades, a large number of protocols has been proposed, characterized by specific reagents and experimental conditions (concentrations, number of steps, extraction orders and solid/solution ratio) (Das et al., 1995; Gomez Ariza et al., 2000; Quevauviller et al., 1994; Rauret, 1998; Tack and Verloo, 1995), but it appeared that several of them suffer from a lack of selectivity of applied reagents: besides target ones, some of them are able to leach several solid phases. In this context, the aim of the present study is to investigate the effectiveness and the selectivity of different reagents for metal extraction from target geochemical fraction. It is based on solid analyses with the use of X-ray diffraction and a scanning electron microscopy (SEM) coupled to a microRaman spectrometer in conjunction with chemical analyses of extracting solutions at each step. This methodology provides the opportunity to assess more accurately the effect of each reagent. The study focuses on extraction of Cu and Zn from sediment samples collected at two sites from river banks and characterized by presence of Quartz, Feldspar K, Micas, Kaolinite but with differences regarding accessory phases (pyrite, organic matter, iron oxy- hydroxide, calcite). The interaction of the samples with eight different reagents was assessed and compared (Ca(NO3)2 and CaCl2 for the exchangeable fraction; buffered solutions of sodium acetate/acetic acid at pH = 5.5 and pH = 5 for the acido-soluble fraction; hydroxylamine hydrochloride and a solution of ammonium oxalate/oxalic acid for reducible fraction; hydrogen peroxide and sodium hypochlorite for the oxidizable fraction. In-depth characterization of solid residue at each step allowed proposing the best protocol for both metals. Anderson, P., Davidson, C. M., Duncan, A. L., Littlejohn, D., Ure, A. M., and Garden, L. M. (2000). Column leaching and sorption experiments to assess the mobility of potentially toxic elements in industrially contaminated land. Journal of Environmental Monitoring, 2. Arey, J. S., Seaman, J. C., and Bertsch, P. M. (1999). Immobilization of uranium in contaminated sediments by hydroxyapatite addition. Environmental Science & Technology, 33, 337-342. Brannon, J. M., and Patrick, W. H. (1987). Fixation, transformation, and mobilization of arsenic in sediments.Environmental Science & Technology, 21, 450-459. Cornu, S., and Clozel, B. (2000). Extractions séquentielles et spéciation des éléments trace métalliques dans les sols naturels. Analyse critique. 7, 179-189. Das, A. K., Chakraborty, R., Cervera, M. L., and Delaguardia, M. (1995). Metal speciation in solid matrices. Talanta, 42. Gomez Ariza, J. L., Giraldez, I., Sanchez-Rodas, D., and Morales, E. (2000). Selectivity assessment of a sequential extraction procedure for metal mobility characterization using model phases. Talanta, 52, 545-554. Hickey, M. G., and Kittrick, J. A. (1984). Chemical partitioning of cadmium, copper, nickel and zinc in soils and sediments containing high-levels of heavy metals. Journal of Environmental Quality, 13, 372-376. La Force, M. J., Fendorf, S., Li, G. C., and Rosenzweig, R. F. (1999). Redistribution of trace elements from contaminated sediments of Lake Coeur d'Alene during oxygenation. Journal of Environmental Quality, 28, 1195-1200. Quevauviller, P., Rauret, G., Muntau, H., Ure, A. M., Rubio, R., Lopezsanchez, J. F., Fiedler, H. D., and Griepink, B. (1994). Evaluation of a sequential extraction procedure for the determination of extractable trace-metal contents in sediments. Fresenius Journal of Analytical Chemistry, 349. Rauret, G. (1998). Extraction procedures for the determination of heavy metals in contaminated soil and sediment. Talanta, 46(3), 449-455. Sterckeman, T., Douay, F., Baize, D., Fourrier, H., Proix, N., and Schvartz, C. (2004). Factors affecting trace element concentrations in soils developed on recent marine deposits from northern France. Applied Geochemistry, 19. Tack, F. M. G., and Verloo, M. G. (1995). Chemical speciation and fraéctination in soil and sediment heavy-metal analysis - a review. International Journal of Environmental Analytical Chemistry, 59, 225-238. Tessier, A., Campbell, P. G. C., and Bisson, M. (1979). Sequential extraction procedure for the speciation of particulate trace-metals. Analytical Chemistry, 51. Van Oort, F., Jongmans, A. G., Lamy, I., Baize, D., and Chevallier, P. (2008). Impacts of long-term waste-water irrigation on the development of sandy Luvisols: consequences for metal pollutant distributions. European Journal of Soil Science, 59.

Spontaneous plant colonization of brownfield soil and sludges and effects on substrate properties and pollutants mobility

NASA Astrophysics Data System (ADS)

Rocco, Claudia; Agrelli, Diana; Gonzalez, Maria Isabel; Mingo, Antonio; Motti, Riccardo; Stinca, Adriano; Coppola, Ida; Adamo, Paola

2017-04-01

This work was done on brownfield soil and sludges from a dismantled steel plant, moderately polluted by heavy metals (mainly Pb and Zn), 1) to analyzed the effects of substrate properties and environmental conditions on spontaneous vegetation; 2) to assess changes in the chemical properties of soils and sludges, with particular reference to the mobility and bioavailability of pollutants, induced by spontaneous plants revegetation. From 2006 to 2011, spontaneous plant colonization was monitored in the presence or absence of acidic peat both inside the degraded brownfield site and after transferal into a nearby Oak Park environment. During the five experimental years the vegetation growth was monitored using phytosociological method and data analyzed statistically. Both substrates, before and after plant growth, were analyzed for main chemical properties. Metals mobility and bioavailability was assessed using single (H2O; DTPA) and sequential extractions (EU-BCR). At the end of the experiment, plant ability to uptake metal was evaluated on selected species. Overall, 57 plant species grew healthily on the substrates. The combination of soil and sludges with peat resulted in an effective revegetation with a sensible increasing of plants biomass. Most of the species were found in the park (91%), showing plant colonization was mainly affected by the immediate environment rather than by substrate properties. Furthermore, after the five years, the substrate properties (pH, O.C.) were slightly affected by plant growth and, although metal pollutants in both substrates are characterized by low water solubility and DTPA availability, after plants growth an increase (even if not significant) of rhizospheric Cu, Fe, Mn and Zn solubility in H2O was detected. Metals speciation indicated a low risk of Pb and Zn mobility being either largely trapped in the mineralogical structure of oxides and silicates and occluded in easily reducible manganese or iron oxides. Restricted metal uptake and tissue accumulation by selected plants were measured, with only Daucus carota showing a higher ability to translocate metals to shoots (shoot/root metal concentration quotient >1 with peat). Water always underestimated plant uptake, while DTPA and sequential extractions better predicted Pb and Zn uptake. Phytostabilization with native plant species can be an efficient, environmentally appropriate and low cost technology for rehabilitation of industrial sites. The addition of organic matter may help the spontaneous re-vegetation and could facilitate the recovery of degraded environment. However, the changing induced by peat and plants might induced a solubilization of metal pollutants. A continuous monitoring of the potential changes of pollutants mobility-bioavailability by plants is crucial to prevent risks to the environment and human health. Key words: Heavy metals, phytoremediation, Peat addition, bioavailability, sequential extractions

Mining sequential patterns for protein fold recognition.

PubMed

Exarchos, Themis P; Papaloukas, Costas; Lampros, Christos; Fotiadis, Dimitrios I

2008-02-01

Protein data contain discriminative patterns that can be used in many beneficial applications if they are defined correctly. In this work sequential pattern mining (SPM) is utilized for sequence-based fold recognition. Protein classification in terms of fold recognition plays an important role in computational protein analysis, since it can contribute to the determination of the function of a protein whose structure is unknown. Specifically, one of the most efficient SPM algorithms, cSPADE, is employed for the analysis of protein sequence. A classifier uses the extracted sequential patterns to classify proteins in the appropriate fold category. For training and evaluating the proposed method we used the protein sequences from the Protein Data Bank and the annotation of the SCOP database. The method exhibited an overall accuracy of 25% in a classification problem with 36 candidate categories. The classification performance reaches up to 56% when the five most probable protein folds are considered.

An Immunoglobulin G1 Monoclonal Antibody Highly Specific to the Wall of Cryptosporidium Oocysts

PubMed Central

Weir, C.; Vesey, G.; Slade, M.; Ferrari, B.; Veal, D. A.; Williams, K.

2000-01-01

The detection of Cryptosporidium oocysts in drinking water is critically dependent on the quality of immunofluorescent reagents. Experiments were performed to develop a method for producing highly specific antibodies to Cryptosporidium oocysts that can be used for water testing. BALB/c mice were immunized with six different antigen preparations and monitored for immunoglobulin G (IgG) and IgM responses to the surface of Cryptosporidium oocysts. One group of mice received purified oocyst walls, a second group received a soluble protein preparation extracted from the outside of the oocyst wall, and the third group received whole inactivated oocysts. Three additional groups were immunized with sequentially prepared oocyst extracts to provide for a comparison of the immune response. Mice injected with the soluble protein extract demonstrated an IgG response to oocysts surface that was not seen in the whole-oocyst group. Mice injected with whole oocysts showed an IgM response only, while mice injected with purified oocyst walls showed little increase in IgM or IgG levels. Of the additional reported preparations only one, BME (2-mercaptoethanol treated), produced a weak IgM response to the oocyst wall. A mouse from the soluble oocyst extract group yielding a high IgG response was utilized to produce a highly specific IgG1 monoclonal antibody (Cry104) specific to the oocyst surface. Comparative flow cytometric analysis indicated that Cry104 has a higher avidity and specificity to oocysts in water concentrates than other commercially available antibodies. PMID:10973448

Identifying, Quantifying, Extracting and Enhancing Implicit Parallelism

ERIC Educational Resources Information Center

Agarwal, Mayank

2009-01-01

The shift of the microprocessor industry towards multicore architectures has placed a huge burden on the programmers by requiring explicit parallelization for performance. Implicit Parallelization is an alternative that could ease the burden on programmers by parallelizing applications "under the covers" while maintaining sequential semantics…

Experiences with digital processing of images at INPE

NASA Technical Reports Server (NTRS)

Mascarenhas, N. D. A. (Principal Investigator)

1984-01-01

Four different research experiments with digital image processing at INPE will be described: (1) edge detection by hypothesis testing; (2) image interpolation by finite impulse response filters; (3) spatial feature extraction methods in multispectral classification; and (4) translational image registration by sequential tests of hypotheses.

Particle size and chemical control of heavy metals in bed sediment from the Rouge River, southeast Michigan

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

Murray, K.S.; Cauvet, D.; Lybeer, M.

1999-04-01

Anthropogenic activities related to 100 years of industrialization in the metropolitan Detroit area have significantly enriched the bed sediment of the lower reaches of the Rouge River in Cr, Cu, Fe, Ni, Pb, and Zn. These enriched elements, which may represent a threat to biota, are predominantly present in sequentially extracted reducible and oxidizable chemical phases with small contributions from residual phases. In size-fractionated samples trace metal concentrations generally increase with decreasing particle size, with the greatest contribution to this increase from the oxidizable phase. Experimental results obtained on replicate samples of river sediment demonstrate that the accuracy of themore » sequential extraction procedure, evaluated by comparing the sums of the three individual fractions, is generally better than 10%. Oxidizable and reducible phases therefore constitute important sources of potentially available heavy metals that need to be explicitly considered when evaluating sediment and water quality impacts on biota.« less

Evaluating the Mobility of Arsenic in Synthetic Iron-containing Solids Using a Modified Sequential Extraction Method.

PubMed

Shan, Jilei; Sáez, A Eduardo; Ela, Wendell P

2010-02-01

Many water treatment technologies for arsenic removal that are used today produce arsenic-bearing residuals which are disposed in non-hazardous landfills. Previous works have established that many of these residuals will release arsenic to a much greater extent than predicted by standard regulatory leaching tests (e.g. the toxicity characteristic leaching procedure, TCLP) and, consequently, require stabilization to ensure benign behavior after disposal. In this work, a four-step sequential extraction method was developed in an effort to determine the proportion of arsenic in various phases in untreated as well as stabilized iron-based solid matrices. The solids synthesized using various potential stabilization techniques included: amorphous arsenic-iron sludge (ASL), reduced ASL via reaction with zero valent iron (RASL), amorphous ferrous arsenate (PFA), a mixture of PFA and SL (M1), crystalline ferrous arsenate (HPFA), and a mixture of HPFA and SL (M2). The overall arsenic mobility of the tested samples increased in the following order: ASL > RASL > PFA > M1 > HPFA > M2.

The composition of potentially bioactive triterpenoid glycosides in red raspberry is influenced by tissue, extraction procedure and genotype.

PubMed

McDougall, Gordon J; Allwood, J William; Pereira-Caro, Gema; Brown, Emma M; Latimer, Cheryl; Dobson, Gary; Stewart, Derek; Ternan, Nigel G; Lawther, Roger; O'Connor, Gloria; Rowland, Ian; Crozier, Alan; Gill, Chris I R

2017-10-18

The beneficial effects of consumption of berry fruits on a range of chronic diseases has been attributed (at least in part) to the presence of unique phytochemicals. Recently, we identified novel ursolic acid-based triterpenoid glycosides (TTPNs) in raspberry fruit and demonstrated their survival in human ileal fluids after feeding which confirmed their colon-availability in vivo. In this paper, in vitro digestion studies demonstrated that certain TTPNs were stable under gastrointestinal conditions and confirmed that these components may have been responsible for bioactivity noted in previous studies. Sequential extractions of raspberry puree, isolated seeds and unseeded puree showed that certain TTPN components (e.g. peak T1 m/z 679, and T2 m/z 1358) had different extractabilities in water/solvent mixes and were differentially associated with the seeds. Purified seed TTPNs (mainly T1 and T2) were shown to be anti-genotoxic in HT29 and CCD841 cell based in vitro colonocyte models. Further work confirmed that the seeds contained a wider range of TTPN-like components which were also differentially extractable in water/solvent mixes. This differential extractability could influence the TTPN composition and potential bioactivity of the extracts. There was considerable variation in total content of TTPNs (∼3-fold) and TTPN composition across 13 Rubus genotypes. Thus, TTPNs are likely to be present in raspberry juices and common extracts used for bioactivity studies and substantial variation exists in both content and composition due to genetics, tissue source or extraction conditions, which may all affect observed bioactivity.

Estimation of Cadmium uptake by tobacco plants from laboratory leaching tests.

PubMed

Marković, Jelena P; Jović, Mihajlo D; Smičiklas, Ivana D; Šljivić-Ivanović, Marija Z; Smiljanić, Slavko N; Onjia, Antonije E; Popović, Aleksandar R

2018-03-21

The objective of the present study was to determine the impact of cadmium (Cd) concentration in the soil on its uptake by tobacco plants, and to compare the ability of diverse extraction procedures for determining Cd bioavailability and predicting soil-to-plant transfer and Cd plant concentrations. The pseudo-total digestion procedure, modified Tessier sequential extraction and six standard single-extraction tests for estimation of metal mobility and bioavailability were used for the leaching of Cd from a native soil, as well as samples artificially contaminated over a wide range of Cd concentrations. The results of various leaching tests were compared between each other, as well as with the amounts of Cd taken up by tobacco plants in pot experiments. In the native soil sample, most of the Cd was found in fractions not readily available under natural conditions, but with increasing pollution level, Cd amounts in readily available forms increased. With increasing concentrations of Cd in the soil, the quantity of pollutant taken up in tobacco also increased, while the transfer factor (TF) decreased. Linear and non-linear empirical models were developed for predicting the uptake of Cd by tobacco plants based on the results of selected leaching tests. The non-linear equations for ISO 14870 (diethylenetriaminepentaacetic acid extraction - DTPA), ISO/TS 21268-2 (CaCl 2 leaching procedure), US EPA 1311 (toxicity characteristic leaching procedure - TCLP) single step extractions, and the sum of the first two fractions of the sequential extraction, exhibited the best correlation with the experimentally determined concentrations of Cd in plants over the entire range of pollutant concentrations. This approach can improve and facilitate the assessment of human exposure to Cd by tobacco smoking, but may also have wider applicability in predicting soil-to-plant transfer.

Selective dissolution followed by EDDS washing of an e-waste contaminated soil: Extraction efficiency, fate of residual metals, and impact on soil environment.

PubMed

Beiyuan, Jingzi; Tsang, Daniel C W; Valix, Marjorie; Zhang, Weihua; Yang, Xin; Ok, Yong Sik; Li, Xiang-Dong

2017-01-01

To enhance extraction of strongly bound metals from oxide minerals and organic matter, this study examined the sequential use of reductants, oxidants, alkaline solvents and organic acids followed by a biodegradable chelating agent (EDDS, [S,S]-ethylene-diamine-disuccinic-acid) in a two-stage soil washing. The soil was contaminated by Cu, Zn, and Pb at an e-waste recycling site in Qingyuan city, China. In addition to extraction efficiency, this study also examined the fate of residual metals (e.g., leachability, bioaccessibility, and distribution) and the soil quality parameters (i.e., cytotoxicity, enzyme activities, and available nutrients). The reductants (dithionite-citrate-bicarbonate and hydroxylamine hydrochloride) effectively extracted metals by mineral dissolution, but elevated the leachability and bioaccessibility of metals due to the transformation from Fe/Mn oxides to labile fractions. Subsequent EDDS washing was found necessary to mitigate the residual risks. In comparison, prior washing by oxidants (persulphate, hypochlorite, and hydrogen peroxide) was marginally useful because of limited amount of soil organic matter. Prior washing by alkaline solvents (sodium hydroxide and sodium bicarbonate) was also ineffective due to metal precipitation. In contrast, prior washing by low-molecular-weight organic acids (citrate and oxalate) improved the extraction efficiency. Compared to hydroxylamine hydrochloride, citrate and oxalate induced lower cytotoxicity (Microtox) and allowed higher enzyme activities (dehydrogenase, acid phosphatase, and urease) and soil nutrients (available nitrogen and phosphorus), which would facilitate reuse of the treated soil. Therefore, while sequential washing proved to enhance extraction efficacy, the selection of chemical agents besides EDDS should also include the consideration of effects on metal leachability/bioaccessibility and soil quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

A novel dual-valve sequential injection manifold (DV-SIA) for automated liquid-liquid extraction. Application for the determination of picric acid.

PubMed

Skrlíková, Jana; Andruch, Vasil; Sklenárová, Hana; Chocholous, Petr; Solich, Petr; Balogh, Ioseph S

2010-05-07

A novel dual-valve sequential injection system (DV-SIA) for online liquid-liquid extraction which resolves the main problems of LLE utilization in SIA has been designed. The main idea behind this new design was to construct an SIA system by connecting two independent units, one for aqueous-organic mixture flow and the second specifically for organic phase flow. As a result, the DV-SIA manifold consists of an Extraction unit and a Detection unit. Processing a mixture of aqueous-organic phase in the Extraction unit and a separated organic phase in the Detection unit solves the problems associated with the change of phases having different affinities to the walls of the Teflon tubing used in the SI-system. The developed manifold is a simple, user-friendly and universal system built entirely from commercially available components. The system can be used for a variety of samples and organic solvents and is simple enough to be easily handled by operators less familiar with flow systems. The efficiency of the DV-SIA system is demonstrated by the extraction of picric acid in the form of an ion associate with 2-[2-(4-methoxy-phenylamino)-vinyl]-1,3,3-trimethyl-3H-indolium reagent, with subsequent spectrophotometric detection. The suggested DV-SIA concept can be expected to stimulate new experiments in analytical laboratories and can be applied to the elaboration of procedures for the determination of other compounds extractable by organic solvents. It could thus form a basis for the design of simple, single-purpose commercial instruments used in LLE procedures. 2010 Elsevier B.V. All rights reserved.

The involvement of immunoglobulin E isotype switch in scleroderma skin tissue.

PubMed

Ohtsuka, Tsutomu; Yamazaki, Soji

2005-08-01

The involvement of mast cell, which is activated by immunoglobulin E (IgE), has been reported in the formation of systemic sclerosis (SSc) abnormality. IgE is generated with isotype switch. During isotype switch, switch circles resulting from direct mu to epsilon, or from sequential mu to gamma via epsilon switching will be created. We studied whether switching occurs in SSc. We used nested polymerase chain reaction to analyze the S fragments from switch circles. Fifty-two patients with SSc, and 62 healthy women were studied. Neither of 62 normal skin tissues showed direct switch, nor sequential switch. Neither of seven normal whole blood cells showed direct switch, nor sequential switch. In 52SSc skin tissues, three (5.8%) showed direct switch, and two (3.8%) showed sequential switch. As a result, five (9.6%) of SSc skin tissue showed immunogobulin E class switch. These results were confirmed by DNA sequencing. These results demonstrated that isotype switch to the epsilon locus achieved by direct and/or sequential switch are involved in SSc skin.

Inhibitory effect of Terminalia chebula Retz. fruit extracts on digestive enzyme related to diabetes and oxidative stress.

PubMed

Sasidharan, Indu; Sundaresan, A; Nisha, V M; Kirishna, Mahesh S; Raghu, K G; Jayamurthy, P

2012-08-01

Terminalia chebula fruit extracts were prepared sequentially with hexane, ethyl acetate, methanol and methanol-water (70:30) and tested for their α-glucosidase inhibitory and antioxidant potential. The study resulted in the formulation of an extract with high α-glucosidase inhibitory potential (IC(50) 0.19 ± 0.03 µg mL(-1)) enriched with hydrolysable tannins. Also, each of the extract was chemically characterized by reversed-phase high-performance liquid chromatography on the basis of their marker compounds chebulagic acid, chebulinic acid and corilagin in order to give explanation to the significant activity shown by the extracts. The antioxidant potential of the highly active extract was evaluated in the cellular level also using superoxide dismutase, glutathione S-transferase and induced oxidative stress assays. The results indicated the possibility of using the extract as a nutraceutical health supplement in the management of type 2 diabetes.

Hypocholesterolemic property of Yucca schidigera and Quillaja saponaria extracts in human body.

PubMed

Kim, Sang-Woo; Park, Sang-Kyu; Kang, Sung-Il; Kang, Han-Chul; Oh, Han-Jin; Bae, Chul-Young; Bae, Dong-Ho

2003-12-01

This study was undertaken to observe the effects of the blend of partially purified Yucca schidigera and Quillaja saponaria extracts on cholesterol levels in the human's blood and gastrointestinal functions, and to determine if a new cholesterol-lowering drug can be developed by the further purification of the extracts. Ultrafiltration and sequential diafiltration increased the amounts of steroidal saponin in aqueous yucca extract and terpenoid saponin in aqueous quillaja extract from 9.3% and 21.4% to 17.2% and 61.8%, respectively. Taking 0.9 mg of the blend (6:4, v:v) of the resulting filtrates a day for 4 weeks resulted in the decreases in total and LDL cholesterol levels in blood plasma of hyper-cholesterolemic patients with enhancement in gastrointestinal symptoms of patients.

Kurtosis-Based Blind Source Extraction of Complex Non-Circular Signals with Application in EEG Artifact Removal in Real-Time

PubMed Central

Javidi, Soroush; Mandic, Danilo P.; Took, Clive Cheong; Cichocki, Andrzej

2011-01-01

A new class of complex domain blind source extraction algorithms suitable for the extraction of both circular and non-circular complex signals is proposed. This is achieved through sequential extraction based on the degree of kurtosis and in the presence of non-circular measurement noise. The existence and uniqueness analysis of the solution is followed by a study of fast converging variants of the algorithm. The performance is first assessed through simulations on well understood benchmark signals, followed by a case study on real-time artifact removal from EEG signals, verified using both qualitative and quantitative metrics. The results illustrate the power of the proposed approach in real-time blind extraction of general complex-valued sources. PMID:22319461

Development of soft extraction method for structural characterization of boreal forest soil proteins with MALDI-TOF/MS

NASA Astrophysics Data System (ADS)

Kanerva, Sanna; Ketola, Raimo A.; Kitunen, Veikko; Smolander, Aino; Kotiaho, Tapio

2010-05-01

Nitrogen (N) is usually the nutrient restricting productivity in boreal forests. Forest soils contain a great amount of nitrogen, but only a small part of it is in mineral form. Most part of soil N is bound in the structures of different organic compounds such as proteins, peptides, amino acids and more stabilized, refractory compounds. Due to the fact that soil organic N has a very important role in soil nutrient cycling and in plant nutrition, there is a need for more detailed knowledge of its chemistry in soil. Conventional methods to extract and analyze soil organic N are usually very destructive for structures of higher molecular weight organic compounds, such as proteins. The aim of this study was to characterize proteins extracted from boreal forest soil by "soft" extraction methods in order to maintain their molecular structure. The organic layer (F) from birch forest floor containing 78% of organic matter was sieved, freeze dried, pulverized, and extracted with a citrate or phosphate buffer (pH 6 or 8). Sequential extraction with the citrate or phosphate buffer and an SDS buffer (pH 6.8), slightly modified from the method of Chen et al. (2009, Proteomics 9: 4970-4973), was also done. Proteins were purified from the soil extract by extraction with buffered phenol and precipitated with methanol + 0.1M ammonium acetate at -20°C. Characterization of proteins was performed with matrix assisted laser desorption ionization - time-of-flight mass spectrometry (MALDI-TOF/MS) and the concentration of total proteins was measured using Bradford's method. Bovine serum albumin (BSA) was used as a positive control in the extractions and as a standard protein in Bradford's method. Our results showed that sequential extraction increased the amount of extracted proteins compared to the extractions without the SDS-buffer; however, it must be noted that the use of SDS-buffer very probably increased denaturization of proteins. Purification of proteins from crude soil extracts by phenol extraction was essential prior to measurement of total proteins; there seemed to be a lot of compounds in crude soil extracts that interfere with the analysis of total proteins, causing overestimation in protein concentration. pH of the buffer solution did not seem to be very crucial for the extractability of soil natural proteins, but at the higher pH, the amount of interfering compounds increased. However, the recovery of BSA added was clearly higher at the higher pH. When the protein precipitates were analyzed with MALDI-TOF/MS, a large curve, most likely formed from wide peaks of several compounds, indicate that most of the compounds in the precipitate were <15 kDa or ~20-50 kDa in molecular weight. It seems that in order to identify individual proteins from mass spectra, a separation of compounds with varying molecular weight is needed before the MALDI-TOF/MS analysis. Due to the fact that a relatively high amount of BSA added was not recovered by the extractions and that the intensity of the signals observed in mass spectra was low, it is questionable whether it is possible to extract soil natural proteins effectively from soils containing a high amount of organic matter without destructing the structures of proteins.

Speciation of mercury in sludge solids: washed sludge

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

Bannochie, C. J.; Lourie, A. P.

2017-10-24

The objective of this applied research task was to study the type and concentration of mercury compounds found within the contaminated Savannah River Site Liquid Waste System (SRS LWS). A method of selective sequential extraction (SSE), developed by Eurofins Frontier Global Sciences1,2 and adapted by SRNL, utilizes an extraction procedure divided into seven separate tests for different species of mercury. In the SRNL’s modified procedure four of these tests were applied to a washed sample of high level radioactive waste sludge.

Efficacy of different methanolic plant extracts on anti-methanogenesis, rumen fermentation and gas production kinetics in vitro

PubMed Central

Sirohi, S.K.; Goel, N.; Pandey, P.

2012-01-01

The present study was carried out to evaluate the effect of methanolic extracts of three plants, mehandi (Lawsonia inermis), jaiphal (Myristica fragrans) and green chili (Capsicum annuum) on methanogenesis, rumen fermentation and fermentation kinetic parameters by in vitro gas production techniques. Single dose of each plant extract (1 ml / 30 ml buffered rumen fluid) and two sorghum fodder containing diets (high and low fiber diets) were used for evaluating the effect on methanogenesis and rumen fermentation pattern, while sequential incubations (0, 1, 2, 3, 6 9, 12, 24, 36, 48, 60, 72 and 96 h) were carried out for gas production kinetics. Results showed that methane production was reduced, ammonia nitrogen was increased significantly, while no significant effect was found on pH and protozoal population following addition of different plant extracts in both diets except mehandi. Green chili significantly reduced digestibility of dry matter, total fatty acid and acetate concentration at incubation with sorghum based high and low fiber diets. Among all treatments, green chili increased potential gas production, while jaiphal decreased the gas production rate constant significantly. The present results demonstrate that methanolic extracts of different plants are promising rumen modifying agents. They have the potential to modulate the methane production, potential gas production, gas production rate constant, dry matter digestibility and microbial biomass synthesis. PMID:26623296

Efficacy of different methanolic plant extracts on anti-methanogenesis, rumen fermentation and gas production kinetics in vitro.

PubMed

Sirohi, S K; Goel, N; Pandey, P

2012-01-01

The present study was carried out to evaluate the effect of methanolic extracts of three plants, mehandi (Lawsonia inermis), jaiphal (Myristica fragrans) and green chili (Capsicum annuum) on methanogenesis, rumen fermentation and fermentation kinetic parameters by in vitro gas production techniques. Single dose of each plant extract (1 ml / 30 ml buffered rumen fluid) and two sorghum fodder containing diets (high and low fiber diets) were used for evaluating the effect on methanogenesis and rumen fermentation pattern, while sequential incubations (0, 1, 2, 3, 6 9, 12, 24, 36, 48, 60, 72 and 96 h) were carried out for gas production kinetics. Results showed that methane production was reduced, ammonia nitrogen was increased significantly, while no significant effect was found on pH and protozoal population following addition of different plant extracts in both diets except mehandi. Green chili significantly reduced digestibility of dry matter, total fatty acid and acetate concentration at incubation with sorghum based high and low fiber diets. Among all treatments, green chili increased potential gas production, while jaiphal decreased the gas production rate constant significantly. The present results demonstrate that methanolic extracts of different plants are promising rumen modifying agents. They have the potential to modulate the methane production, potential gas production, gas production rate constant, dry matter digestibility and microbial biomass synthesis.

Sequential healing of open extraction sockets. An experimental study in monkeys.

PubMed

Scala, Alessandro; Lang, Niklaus P; Schweikert, Michael T; de Oliveira, José Américo; Rangel-Garcia, Idelmo; Botticelli, Daniele

2014-03-01

To describe the sequential healing of open extraction sockets at which no attempts to obtain a primary closure of the coronal access to the alveolus have been made. The third mandibular premolar was extracted bilaterally in 12 monkeys, and no sutures were applied to close the wound. The healing after 4, 10, 20, 30, 90 and 180 days was morphometrically studied. After 4 days of healing, a blood clot mainly occupied the extraction sockets, with the presence of an inflammatory cells' infiltrate. A void was confined in the central zones of the coronal and middle regions, in continuity with the entrance of the alveoli. At 10 days, the alveolus was occupied by a provisional matrix, with new bone formation lining the socket bony walls. At 20 days, the amount of woven bone was sensibly increasing. At 30 days, the alveolar socket was mainly occupied by mineralized immature bone at different stages of healing. At 90 and 180 days, the amount of mineralized bone decreased and substituted by trabecular bone and bone marrow. Bundle bone decreased from 95.5% at 4 days to 7.6% at 180 days, of the whole length of the inner alveolar surface. Modeling processes start from the lateral and apical walls of the alveolus, leading to the closure of the socket with newly formed bone within a month from extraction. Remodeling processes will follow the previous stages, resulting in trabecular and bone marrow formation and in a corticalization of the socket access. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Real-time sensing of lint quality

USDA-ARS?s Scientific Manuscript database

Modem cotton gins have the purpose of extracting lint (the cotton) from trash and seeds- usually the sticks, leaves and burrs that are entrained with the cotton. These modem gins include many individual machine components that are operated sequentially to form the gin processing line. Recent on-line...

Pitch Fractionation.

DTIC Science & Technology

1981-12-15

The solvent fractions were obtained by sequential Soxhlet extraction with solvents such as hexane, cyclohexane, toluene, and pyridine. The most severe...Continued) *.AISYRACT (Continued) fraction increased, the pyrolysis yield and bloating increased, and the msicrostructure of the coke became finer...28 8. Coking Yield and Bloating Behavior of Fractionation Sequence AG 162-4

Intrinsic fluorescence excitation-emission matrix spectral features of cottonseed protein fractions and the effects of denaturants

USDA-ARS?s Scientific Manuscript database

To better understand the functional and physicochemical properties of cottonseed protein, we investigated the intrinsic fluorescence excitation-emission matrix (EEM) spectral features of cottonseed protein isolate (CSPI) and sequentially extracted water (CSPw) and alkali (CSPa) protein fractions, an...

ASSESSING SPECIATION AND RELEASE OF HEAVY METALS FROM COAL COMBUSTION PRODUCTS

EPA Science Inventory

In this study, the speciation of heavy metals such as arsenic, selenium, lead, zinc and mercury in coal combustion products (CCPs) was evaluated using sequential extraction procedures. Coal fly ash, bottom ash and flue gas desulphurization (FGD) sludge samples were used in the ex...

Ixora coccinea Enhances Cutaneous Wound Healing by Upregulating the Expression of Collagen and Basic Fibroblast Growth Factor

PubMed Central

Upadhyay, Aadesh; Chattopadhyay, Pronobesh; Goyary, Danswrang; Mitra Mazumder, Papiya; Veer, Vijay

2014-01-01

Background. Ixora coccinea L. (Rubiaceae) has been documented for traditional use in hypertension, menstrual irregularities, sprain, chronic ulcer, and skin diseases. In the present study, I. coccinea was subjected to in vitro and in vivo wound healing investigation. Methods. Petroleum ether, chloroform, methanol, and water sequential I. coccinea leaves extracts were evaluated for in vitro antioxidant, antimicrobial, and fibroblast proliferation activities. The promising I. coccinea methanol extract (IxME) was screened for in vivo wound healing activity in Wistar rat using circular excision model. Wound contraction measurement, hydroxyproline quantification, and western blot for collagen type III (COL3A1), basic fibroblast growth factor (bFGF), and Smad-2, -3, -4, and -7 was performed with 7-day postoperative wound granulation tissue. Gentamicin sulfate (0.01% w/w) hydrogel was used as reference standard. Results. IxME showed the potent antimicrobial, antioxidant activities, with significant fibroblast proliferation inducing activity, as compared to all other extracts. In vivo study confirmed the wound healing accelerating potential of IxME, as evidenced by faster wound contraction, higher hydroxyproline content, and improved histopathology of granulation tissue. Western blot analysis revealed that the topical application of I. coccinea methanol extract stimulates the fibroblast growth factor and Smad mediated collagen production in wound tissue. PMID:24624303

Assessment of the analgesic, anti-inflammatory and sedative effects of the dichloromethanol extract of Schinus molle.

PubMed

Taylor, A; Oyedeji, O O; Aremu, O; Oyemitan, I; Gwebu, E T; Oyedeji, A O; Nkeh-Chungag, B N

2016-01-01

Determination of the active fraction and compounds of the dichloromethanol extract of Schinus molle seeds and evaluation of their biological effects. Dried seeds of Schinus molle were sequentially extracted in hexane, acetyl acetate and dichloromethane. The dichloromethane extract was separated into two fractions (1 and 2) by column chromatography. Fraction 2 was further separated into its two constituent compounds which were characterized as belonging to the lanosteroid group of compounds. Both factions were tested for their analgesic, anti-inflammatory and sedative effects. The two fractions significantly increased (p<0.05) the tail flick latency though fraction 2 provided better and more long lasting protection against thermal pain. On the other hand, the anti-inflammatory effect of ibuprofen, though inferior to the anti-inflammatory effect of fraction 2 was better than the effects of fraction 1. Fraction 2 significantly (p<0.01) reduced rat paw oedema compared to the saline treatment group throughout the experiments while fraction 2 compared to fraction 1 showed significantly (p<0.01) greater inflammatory effects. On the other hand both fractions lacked significant sedative effects. Given that fraction 2 had only two constituent compounds (isomasticadienonic and Masticatrienonate), one or both of these compounds should be contributing to the observed analgesic and anti-inflammatory effects.

Acaricidal and repellent effects of Cnidium officinale-derived material against Dermanyssus gallinae (Acari: Dermanyssidae).

PubMed

Kim, Hyun Kyung; Lee, Seung Ju; Hwang, Bang-Yeon; Yoon, Jong Ung; Kim, Gil-Hah

2018-04-01

The acaricidal activity of a methanolic extract and fractions from the rhizome of Cnidium officinale against Dermanyssus gallinae adults was investigated. The C. officinale methanolic extract exhibited 100% acaricidal activity after 48 h of treatment at a dose of 4000 ppm. The acaricidal constituents of the plant were sequentially partitioned with several solvents and then purified using silica gel column chromatography and high-performance liquid chromatography. Gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy revealed (Z)-ligustilide as a constituent of C. officinale. Acaricidal activity was examined in three experimental tests (spray, fumigation and contact), with the spraying method being the most effective. The methanolic extract of C. officinale showed both contact and fumigant activities, though only fumigant activity was observed with (Z)-ligustilide. The fumigant effects of the methanolic extract and (Z)-ligustilide caused 86.5 and 62.6% mortality, respectively, of D. gallinae adults at 48 h. Among (Z)-ligustilide, acaricides (bifenthrin, cypermethrin and spinosad) and butylidenephthalide, bifenthrin displayed the highest acaricidal activity, and the activity of butylidenephthalide was 2.3-fold higher than that of (Z)-ligustilide. These results suggest that C. officinale-derived material can be used for the development of a control agent for D. gallinae.

Intensive glycaemic control for patients with type 2 diabetes: systematic review with meta-analysis and trial sequential analysis of randomised clinical trials.

PubMed

Hemmingsen, Bianca; Lund, Søren S; Gluud, Christian; Vaag, Allan; Almdal, Thomas; Hemmingsen, Christina; Wetterslev, Jørn

2011-11-24

To assess the effect of targeting intensive glycaemic control versus conventional glycaemic control on all cause mortality and cardiovascular mortality, non-fatal myocardial infarction, microvascular complications, and severe hypoglycaemia in patients with type 2 diabetes. Systematic review with meta-analyses and trial sequential analyses of randomised trials. Cochrane Library, Medline, Embase, Science Citation Index Expanded, LILACS, and CINAHL to December 2010; hand search of reference lists and conference proceedings; contacts with authors, relevant pharmaceutical companies, and the US Food and Drug Administration. Randomised clinical trials comparing targeted intensive glycaemic control with conventional glycaemic control in patients with type 2 diabetes. Published and unpublished trials in all languages were included, irrespective of predefined outcomes. Two reviewers independently assessed studies for inclusion and extracted data related to study methods, interventions, outcomes, risk of bias, and adverse events. Risk ratios with 95% confidence intervals were estimated with fixed and random effects models. Fourteen clinical trials that randomised 28,614 participants with type 2 diabetes (15,269 to intensive control and 13,345 to conventional control) were included. Intensive glycaemic control did not significantly affect the relative risks of all cause (1.02, 95% confidence interval 0.91 to 1.13; 28,359 participants, 12 trials) or cardiovascular mortality (1.11, 0.92 to 1.35; 28,359 participants, 12 trials). Trial sequential analyses rejected a relative risk reduction above 10% for all cause mortality and showed insufficient data on cardiovascular mortality. The risk of non-fatal myocardial infarction may be reduced (relative risk 0.85, 0.76 to 0.95; P=0.004; 28,111 participants, 8 trials), but this finding was not confirmed in trial sequential analysis. Intensive glycaemic control showed a reduction of the relative risks for the composite microvascular outcome (0.88, 0.79 to 0.97; P=0.01; 25,600 participants, 3 trials) and retinopathy (0.80, 0.67 to 0.94; P=0.009; 10,793 participants, 7 trials), but trial sequential analyses showed that sufficient evidence had not yet been reached. The estimate of an effect on the risk of nephropathy (relative risk 0.83, 0.64 to 1.06; 27,769 participants, 8 trials) was not statistically significant. The risk of severe hypoglycaemia was significantly increased when intensive glycaemic control was targeted (relative risk 2.39, 1.71 to 3.34; 27,844 participants, 9 trials); trial sequential analysis supported a 30% increased relative risk of severe hypoglycaemia. Intensive glycaemic control does not seem to reduce all cause mortality in patients with type 2 diabetes. Data available from randomised clinical trials remain insufficient to prove or refute a relative risk reduction for cardiovascular mortality, non-fatal myocardial infarction, composite microvascular complications, or retinopathy at a magnitude of 10%. Intensive glycaemic control increases the relative risk of severe hypoglycaemia by 30%.

Iron content of soils as a precipitation proxy

NASA Astrophysics Data System (ADS)

Dzombak, R.; Sheldon, N. D.

2016-12-01

Given that different iron phases form under different precipitation and drainage regimes, soil iron content could be used as a proxy for both volume and seasonality of precipitation. Constraining these factors is important for predicting future precipitation trends, especially for a warmer climate that will likely see more frequent extreme weather events. Specifically, using paleoprecipitation data from periods of higher temperatures and atmospheric CO2 concentrations helps inform models of future `greenhouse' climate. Forty-five modern samples from across the continental United States were analyzed, with MAP ranging from 200 to 1200 mm yr-1 and MAT ranging from 5 to 22°C. Soil types included Alfisols (N=15), Inceptisols (N=8), Mollisols (N=15), and Aridisols (N=7), and ranged from seasonally wet to well-drained. Analytical techniques included combustion-elemental analysis and organic carbon isotope analysis, a sequential iron extraction modified with a sodium hypochlorite step for the extraction of organic matter-bound iron, and the extraction of iron sulfides. The sequential extractions yield five different `pools' of iron found in sediment: crystalline iron oxides (e.g., goethite, hematite), magnetite, carbonate-bound, organic matter-bound, and labile/easily reducible iron minerals (e.g., ferrihydrite). Analysis by ICP-OES yielded a strong relationship between magnetite-bound iron and MAP, and fair relationships between the other iron pools and MAP. Individual soil orders tended to show stronger relationships to the iron pools than all soils analyzed together, potentially indicating the need for separate proxy relationships for each soil order. Pyrite concentrations were well below 1% by weight for these soils, suggesting that none of these soils has a long enough wet season to encourage its formation and that the presence vs. absence of pyrite in paleosols may be a useful proxy for soil moisture state. In contrast to some earlier work, no significant relationship was found between A horizon δ13C and MAP, but one may emerge as the size of the dataset increases. Ongoing work will include a wider selection of modern soils, increasing the range of both precipitation and temperature, the number of soil orders, and the degree of drainage.

Biological Activities of Asteraceae (Achillea millefolium and Calendula officinalis) and Lamiaceae (Melissa officinalis and Origanum majorana) Plant Extracts.

PubMed

García-Risco, Mónica R; Mouhid, Lamia; Salas-Pérez, Lilia; López-Padilla, Alexis; Santoyo, Susana; Jaime, Laura; Ramírez de Molina, Ana; Reglero, Guillermo; Fornari, Tiziana

2017-03-01

Asteraceae (Achillea millefolium and Calendula officinalis) and Lamiaceae (Melissa officinalis and Origanum majorana) extracts were obtained by applying two sequential extraction processes: supercritical fluid extraction with carbon dioxide, followed by ultrasonic assisted extraction using green solvents (ethanol and ethanol:water 50:50). The extracts were analyzed in terms of the total content of phenolic compounds and the content of flavonoids; the volatile oil composition of supercritical extracts was analyzed by gas chromatography and the antioxidant capacity and cell toxicity was determined. Lamiaceae plant extracts presented higher content of phenolics (and flavonoids) than Asteraceae extracts. Regardless of the species studied, the supercritical extracts presented the lowest antioxidant activity and the ethanol:water extracts offered the largest, following the order Origanum majorana > Melissa officinalis ≈ Achillea millefolium > Calendula officinalis. However, concerning the effect on cell toxicity, Asteraceae (especially Achillea millefolium) supercritical extracts were significantly more efficient despite being the less active as an antioxidant agent. These results indicate that the effect on cell viability is not related to the antioxidant activity of the extracts.

Environmental monitoring and assessment of heavy metals in surface sediments at Coleroon River Estuary in Tamil Nadu, India.

PubMed

Venkatramanan, S; Chung, S Y; Ramkumar, T; Selvam, S

2015-08-01

The combined studies on grain size distribution, organic matter contents of sediments, sequential extraction and bulk concentration of heavy metals, statistical analysis, and ecological risk assessments were carried out to investigate the contamination sources and ecological risks of surface sediments at Coleroon River Estuary in Tamil Nadu, India. The sequential extraction of metals showed that a larger portion of the metals was associated with the residual phase and also in other fractions. The low concentrations of heavy metals were found in exchangeable and carbonate bounds (bioavailable phases). It revealed that sediments of Coleroon River Estuary were relatively unpolluted and were influenced mainly by natural sources. The observed order of bulk concentrations of heavy metals in the sediments was as follows: Fe > Mn > Zn > Cu > Pb > Cr > Ni > Co. Factor analyses represented that the enrichment of heavy metals was mostly resulted from lithogenic origins associated with anthropogenic sources. These sources were reconfirmed by cluster analysis. Risk assessment code (RAC) suggested that all metals were not harmful in monsoon season. However, Fe was in medium risk, and Mn and Cu were in low risk in summer. According to pollution load index (PLI) of sediments, all heavy metals were toxic. Cu might be related with adverse biological effects on the basis of sediment quality guidelines (SQG) in both seasons. These integrated approaches were very useful to identify the contamination sources and ecological risks of sediments in estuarine environment. It is expected that this research can give a useful information for the remediation of heavy metals in sediments.

Full Intelligent Cancer Classification of Thermal Breast Images to Assist Physician in Clinical Diagnostic Applications

PubMed Central

Lashkari, AmirEhsan; Pak, Fatemeh; Firouzmand, Mohammad

2016-01-01

Breast cancer is the most common type of cancer among women. The important key to treat the breast cancer is early detection of it because according to many pathological studies more than 75% – 80% of all abnormalities are still benign at primary stages; so in recent years, many studies and extensive research done to early detection of breast cancer with higher precision and accuracy. Infra-red breast thermography is an imaging technique based on recording temperature distribution patterns of breast tissue. Compared with breast mammography technique, thermography is more suitable technique because it is noninvasive, non-contact, passive and free ionizing radiation. In this paper, a full automatic high accuracy technique for classification of suspicious areas in thermogram images with the aim of assisting physicians in early detection of breast cancer has been presented. Proposed algorithm consists of four main steps: pre-processing & segmentation, feature extraction, feature selection and classification. At the first step, using full automatic operation, region of interest (ROI) determined and the quality of image improved. Using thresholding and edge detection techniques, both right and left breasts separated from each other. Then relative suspected areas become segmented and image matrix normalized due to the uniqueness of each person's body temperature. At feature extraction stage, 23 features, including statistical, morphological, frequency domain, histogram and Gray Level Co-occurrence Matrix (GLCM) based features are extracted from segmented right and left breast obtained from step 1. To achieve the best features, feature selection methods such as minimum Redundancy and Maximum Relevance (mRMR), Sequential Forward Selection (SFS), Sequential Backward Selection (SBS), Sequential Floating Forward Selection (SFFS), Sequential Floating Backward Selection (SFBS) and Genetic Algorithm (GA) have been used at step 3. Finally to classify and TH labeling procedures, different classifiers such as AdaBoost, Support Vector Machine (SVM), k-Nearest Neighbors (kNN), Naïve Bayes (NB) and probability Neural Network (PNN) are assessed to find the best suitable one. These steps are applied on different thermogram images degrees. The results obtained on native database showed the best and significant performance of the proposed algorithm in comprise to the similar studies. According to experimental results, GA combined with AdaBoost with the mean accuracy of 85.33% and 87.42% on the left and right breast images with 0 degree, GA combined with AdaBoost with mean accuracy of 85.17% on the left breast images with 45 degree and mRMR combined with AdaBoost with mean accuracy of 85.15% on the right breast images with 45 degree, and also GA combined with AdaBoost with a mean accuracy of 84.67% and 86.21%, on the left and right breast images with 90 degree, are the best combinations of feature selection and classifier for evaluation of breast images. PMID:27014608

The effect of environmental conditions and soil physicochemistry on phosphate stabilisation of Pb in shooting range soils.

PubMed

Sanderson, Peter; Naidu, Ravi; Bolan, Nanthi

2016-04-01

The stabilisation of Pb in the soil by phosphate is influenced by environmental conditions and physicochemical properties of the soils to which it is applied. Stabilisation of Pb by phosphate was examined in four soils under different environmental conditions. The effect of soil moisture and temperature on stabilisation of Pb by phosphate was examined by measurement of water extractable and bioaccessible Pb, sequential fractionation and X-ray absorption spectroscopy. The addition of humic acid, ammonium nitrate and chloride was also examined for inhibition or improvement of Pb stability with phosphate treatment. The effect of moisture level varied between soils. In soil MB and DA a soil moisture level of 50% water holding capacity was sufficient to maximise stabilisation of Pb, but in soil TV and PE reduction in bioaccessible Pb was inhibited at this moisture level. Providing moisture at twice the soil water holding capacity did not enhance the effect of phosphate on Pb stabilisation. The difference of Pb stability as a result of incubating phosphate treated soils at 18 °C and 37 °C was relatively small. However wet-dry cycles decreased the effectiveness of phosphate treatment. The reduction in bioaccessible Pb obtained was between 20 and 40% with the most optimal treatment conditions. The reduction in water extractable Pb by phosphate was substantial regardless of incubation conditions and the effect of different temperature and soil moisture regimes was not significant. Selective sequential extraction showed phosphate treatment converted Pb in fraction 1 (exchangeable, acid and water soluble) to fraction 2 (reducible). There were small difference in fraction 4 (residual) Pb and fraction 1 as a result of treatment conditions. X-ray absorption spectroscopy of stabilised PE soil revealed small differences in Pb speciation under varying soil moisture and temperature treatments. The addition of humic acid and chloride produced the greatest effect on Pb speciation in phosphate treated soils. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Sediment quality assessment in a coastal lagoon (Ravenna, NE Italy) based on SEM-AVS and sequential extraction procedure.

PubMed

Pignotti, Emanuela; Guerra, Roberta; Covelli, Stefano; Fabbri, Elena; Dinelli, Enrico

2018-09-01

Sediments from the Pialassa Piomboni coastal lagoon (NE Italy) were studied to assess the degree of contamination and ecological risk related to trace metals by combining a geochemical characterization of bulk sediments with the assessment of the bioavailable forms of trace metals. With this purpose, sediment contamination (Cd, Cu, Hg, Ni, Pb, and Zn) was assessed by Enrichment Factors (EFs), and potential bioavailability by the Simultaneously Extracted Metals and Acid Volatile Sulfides (SEM-AVS) approach (Cd, Cu, Ni, Pb, and Zn), and by Sequential Extraction Procedure (Co, Cr, Cu, Ni, Pb, and Zn). On average, Cr and Ni exhibited no contamination (EF ≤1.5), and a predominance in the residual fraction of the sediment, indicating natural origin for these metals. Cu, Pb and Zn displayed a local contamination, which resulted in a higher proportion of Cu bound to the reducible and oxidizable fractions (~30% and ~40% as median, respectively), and Pb mostly associated with the reducible phase (~60% as median). Hence, Cu and Pb could be mobilized when environmental conditions become reducing or oxidizing. Zn resulted mainly partitioned into the reducible and residual fractions (~50% as median, in both fractions). The Risk Assessment Code (RAC) indicated that approximately 30% of samples had >10% of total Zn weakly bound to the sediment, suggesting a medium risk of exposure for aquatic organisms. RAC results were consistent with the ∑SEM-AVS findings, pointing to possible adverse effects for aquatic biota in ~30% of samples, with Zn mostly accounting for the total metal bioavailability. Hg showed a moderate to very severe enrichment, indicating that a substantial amount of this metal derives from anthropogenic sources and may pose adverse effects on the aquatic biota of the Pialassa Piomboni lagoon. Copyright © 2018 Elsevier B.V. All rights reserved.

SHORT-TERM SOLAR FLARE PREDICTION USING MULTIRESOLUTION PREDICTORS

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

Yu Daren; Huang Xin; Hu Qinghua

2010-01-20

Multiresolution predictors of solar flares are constructed by a wavelet transform and sequential feature extraction method. Three predictors-the maximum horizontal gradient, the length of neutral line, and the number of singular points-are extracted from Solar and Heliospheric Observatory/Michelson Doppler Imager longitudinal magnetograms. A maximal overlap discrete wavelet transform is used to decompose the sequence of predictors into four frequency bands. In each band, four sequential features-the maximum, the mean, the standard deviation, and the root mean square-are extracted. The multiresolution predictors in the low-frequency band reflect trends in the evolution of newly emerging fluxes. The multiresolution predictors in the high-frequencymore » band reflect the changing rates in emerging flux regions. The variation of emerging fluxes is decoupled by wavelet transform in different frequency bands. The information amount of these multiresolution predictors is evaluated by the information gain ratio. It is found that the multiresolution predictors in the lowest and highest frequency bands contain the most information. Based on these predictors, a C4.5 decision tree algorithm is used to build the short-term solar flare prediction model. It is found that the performance of the short-term solar flare prediction model based on the multiresolution predictors is greatly improved.« less

Four factors underlying mouse behavior in an open field

PubMed Central

Tanaka, Shoji; Young, Jared W.; Halberstadt, Adam L.; Masten, Virginia L.; Geyer, Mark A.

2012-01-01

The observation of the locomotor and exploratory behaviors of rodents in an open field is one of the most fundamental methods used in the field of behavioral pharmacology. A variety of behaviors can be recorded automatically and can readily generate a multivariate pattern of pharmacological effects. Nevertheless, the optimal ways to characterize observed behaviors and concomitant drug effects are still under development. The aim of this study was to extract meaningful behavioral factors that could explain variations in the observed variables from mouse exploration. Behavioral data were recorded from male C57BL/6J mice (n = 268) using the Behavioral Pattern Monitor (BPM). The BPM data were subjected to the exploratory factor analysis. The factor analysis extracted four factors: activity, sequential organization, diversive exploration, and inspective exploration. The activity factor and the two types of exploration factors correlated positively with one another, while the sequential organization factor negatively correlated with the remaining factors. The extracted factor structure constitutes a behavioral model of mouse exploration. This model will provide a platform on which one can assess the effects of psychoactive drugs and genetic manipulations on mouse exploratory behavior. Further studies are currently underway to examine the factor structure of similar multivariate data sets from humans tested in a human BPM. PMID:22569582

Four factors underlying mouse behavior in an open field.

PubMed

Tanaka, Shoji; Young, Jared W; Halberstadt, Adam L; Masten, Virginia L; Geyer, Mark A

2012-07-15

The observation of the locomotor and exploratory behaviors of rodents in an open field is one of the most fundamental methods used in the field of behavioral pharmacology. A variety of behaviors can be recorded automatically and can readily generate a multivariate pattern of pharmacological effects. Nevertheless, the optimal ways to characterize observed behaviors and concomitant drug effects are still under development. The aim of this study was to extract meaningful behavioral factors that could explain variations in the observed variables from mouse exploration. Behavioral data were recorded from male C57BL/6J mice (n=268) using the Behavioral Pattern Monitor (BPM). The BPM data were subjected to the exploratory factor analysis. The factor analysis extracted four factors: activity, sequential organization, diversive exploration, and inspective exploration. The activity factor and the two types of exploration factors correlated positively with one another, while the sequential organization factor negatively correlated with the remaining factors. The extracted factor structure constitutes a behavioral model of mouse exploration. This model will provide a platform on which one can assess the effects of psychoactive drugs and genetic manipulations on mouse exploratory behavior. Further studies are currently underway to examine the factor structure of similar multivariate data sets from humans tested in a human BPM. Copyright © 2012 Elsevier B.V. All rights reserved.

The Potential of Sequential Extraction in the Characterisation and Management of Wastes from Steel Processing: A Prospective Review

PubMed Central

Rodgers, Kiri J.; Hursthouse, Andrew; Cuthbert, Simon

2015-01-01

As waste management regulations become more stringent, yet demand for resources continues to increase, there is a pressing need for innovative management techniques and more sophisticated supporting analysis techniques. Sequential extraction (SE) analysis, a technique previously applied to soils and sediments, offers the potential to gain a better understanding of the composition of solid wastes. SE attempts to classify potentially toxic elements (PTEs) by their associations with phases or fractions in waste, with the aim of improving resource use and reducing negative environmental impacts. In this review we explain how SE can be applied to steel wastes. These present challenges due to differences in sample characteristics compared with materials to which SE has been traditionally applied, specifically chemical composition, particle size and pH buffering capacity, which are critical when identifying a suitable SE method. We highlight the importance of delineating iron-rich phases, and find that the commonly applied BCR (The community Bureau of reference) extraction method is problematic due to difficulties with zinc speciation (a critical steel waste constituent), hence a substantially modified SEP is necessary to deal with particular characteristics of steel wastes. Successful development of SE for steel wastes could have wider implications, e.g., for the sustainable management of fly ash and mining wastes. PMID:26393631

The Potential of Sequential Extraction in the Characterisation and Management of Wastes from Steel Processing: A Prospective Review.

PubMed

Rodgers, Kiri J; Hursthouse, Andrew; Cuthbert, Simon

2015-09-18

As waste management regulations become more stringent, yet demand for resources continues to increase, there is a pressing need for innovative management techniques and more sophisticated supporting analysis techniques. Sequential extraction (SE) analysis, a technique previously applied to soils and sediments, offers the potential to gain a better understanding of the composition of solid wastes. SE attempts to classify potentially toxic elements (PTEs) by their associations with phases or fractions in waste, with the aim of improving resource use and reducing negative environmental impacts. In this review we explain how SE can be applied to steel wastes. These present challenges due to differences in sample characteristics compared with materials to which SE has been traditionally applied, specifically chemical composition, particle size and pH buffering capacity, which are critical when identifying a suitable SE method. We highlight the importance of delineating iron-rich phases, and find that the commonly applied BCR (The community Bureau of reference) extraction method is problematic due to difficulties with zinc speciation (a critical steel waste constituent), hence a substantially modified SEP is necessary to deal with particular characteristics of steel wastes. Successful development of SE for steel wastes could have wider implications, e.g., for the sustainable management of fly ash and mining wastes.

Potential Transport and Degradation of “Aged” Pesticide Residues in Soil

USDA-ARS?s Scientific Manuscript database

Increased pesticide residence time in soil, or “aging”, has been shown to affect the sorption-desorption of pesticides in the soil, which in turn can control transport and degradation processes. Aging effects have been characterized by batch sequential extraction methods, in which sorption coefficie...

Potential transport and degradation of “Aged” pesticide residues in soil

USDA-ARS?s Scientific Manuscript database

“Aging” has been shown to affect the sorption-desorption of pesticides in the soil, which in turn can control transport and degradation processes. Aging effects have been characterized by batch sequential extraction methods, in which sorption coefficients (i.e. Kd) are determined for the chemical re...

AN IN VITRO GASTROINTESTINAL METHOD TO ESTIMATE BIOAVAILABLE ARSENIC IN CONTAMINATED SOILS AND SOLID MEDIA. (R825410)

EPA Science Inventory

A method was developed to simulate the human gastrointestinal environment and
to estimate bioavailability of arsenic in contaminated soil and solid media. In
this in vitro gastrointestinal (IVG) method, arsenic is sequentially extracted
from contaminated soil with ...

Inorganic mercury binding with different sulfur species in anoxic sediments and their gut juice extractions.

PubMed

Zhong, Huan; Wang, Wen-Xiong

2009-09-01

To investigate the roles of different sulfur (S) species in controlling the partitioning and bioavailability of inorganic mercury (Hg) in anoxic sediments, we examined the differential binding of Hg with three key S species in anoxic sediment (mackinawite [FeS], pyrite [FeS2], and S(2-)) and then quantified their extraction by the gut juice of deposit-feeding sipunculans Sipunculus nudus. A sequential extraction method was simultaneously used to distinguish Hg sorption with different sediment components. All three S-containing sediment components could lead to a high binding of Hg in sediments, but most Hg was sorbed with FeS or FeS2 instead of formation of Hg sulfide despite the presence of S(2-) or humic acid. The gut juice extraction was relatively low and constant whenever FeS and FeS2 were in the sediment, indicating that both FeS and FeS2 controlled the Hg gut juice extraction and thus bioavailability. Mercury sorbed with FeS2 had higher gut juice extraction than that with FeS, while Hg sulfide was not extracted, strongly suggesting that Hg sorbed with FeS2 was more bioavailable than that with other S species. Mercury sorbed with FeS had very low bioavailability to sipunculans at a low Hg:S ratio in the sediment but was more bioavailable with increasing Hg:S ratio up to a maximum (approximately 1:10, mole based). The present study showed that different S species (FeS, FeS2) and Hg:S ratios significantly affected the binding and bioavailability of Hg in anoxic sediments.

Bayesian inversion analysis of nonlinear dynamics in surface heterogeneous reactions.

PubMed

Omori, Toshiaki; Kuwatani, Tatsu; Okamoto, Atsushi; Hukushima, Koji

2016-09-01

It is essential to extract nonlinear dynamics from time-series data as an inverse problem in natural sciences. We propose a Bayesian statistical framework for extracting nonlinear dynamics of surface heterogeneous reactions from sparse and noisy observable data. Surface heterogeneous reactions are chemical reactions with conjugation of multiple phases, and they have the intrinsic nonlinearity of their dynamics caused by the effect of surface-area between different phases. We adapt a belief propagation method and an expectation-maximization (EM) algorithm to partial observation problem, in order to simultaneously estimate the time course of hidden variables and the kinetic parameters underlying dynamics. The proposed belief propagation method is performed by using sequential Monte Carlo algorithm in order to estimate nonlinear dynamical system. Using our proposed method, we show that the rate constants of dissolution and precipitation reactions, which are typical examples of surface heterogeneous reactions, as well as the temporal changes of solid reactants and products, were successfully estimated only from the observable temporal changes in the concentration of the dissolved intermediate product.

VLSI Design of SVM-Based Seizure Detection System With On-Chip Learning Capability.

PubMed

Feng, Lichen; Li, Zunchao; Wang, Yuanfa

2018-02-01

Portable automatic seizure detection system is very convenient for epilepsy patients to carry. In order to make the system on-chip trainable with high efficiency and attain high detection accuracy, this paper presents a very large scale integration (VLSI) design based on the nonlinear support vector machine (SVM). The proposed design mainly consists of a feature extraction (FE) module and an SVM module. The FE module performs the three-level Daubechies discrete wavelet transform to fit the physiological bands of the electroencephalogram (EEG) signal and extracts the time-frequency domain features reflecting the nonstationary signal properties. The SVM module integrates the modified sequential minimal optimization algorithm with the table-driven-based Gaussian kernel to enable efficient on-chip learning. The presented design is verified on an Altera Cyclone II field-programmable gate array and tested using the two publicly available EEG datasets. Experiment results show that the designed VLSI system improves the detection accuracy and training efficiency.

Arabinan-rich pectic polysaccharides from buriti (Mauritia flexuosa): an Amazonian edible palm fruit.

PubMed

Cantu-Jungles, Thaisa Moro; Almeida, Carolina Pierobom de; Iacomini, Marcello; Cipriani, Thales R; Cordeiro, Lucimara M C

2015-05-20

Primary cell wall polysaccharides from aqueous extract of buriti fruit pulp (Mauritia flexuosa, an exotic tropical palm) were isolated and characterized. After freeze-thaw and α-amylase treatments, extracted polysaccharides were purified by sequential ultrafiltration through membranes. Two homogeneous fractions were obtained, SBW-100R and SBW-30R (Mw of 126 kDa and 20 kDa, respectively). Monosaccharide composition, methylation and (13)C NMR analysis showed that fraction SBW-100R contained a (1 → 5)-linked arabinan, branched at O-3 and O-2 positions, linked to a type I rhamnogalacturonan. Low amounts of these polymers were also present in fraction SBW-30R according to (13)C NMR analysis and monosaccharide composition. However, a high methyl esterified homogalacturonan (HG) was present in higher proportions. These results reinforce previous findings present in literature data which indicate that pectic polysaccharides are found in high amounts in primary cell walls of palms, which are commelinid monocotyledons. Copyright © 2015 Elsevier Ltd. All rights reserved.

Combining hydrothermal pretreatment with enzymes de-pectinates and exposes the innermost xyloglucan-rich hemicellulose layers of wine grape pomace.

PubMed

Zietsman, Anscha J J; Moore, John P; Fangel, Jonatan U; Willats, William G T; Vivier, Melané A

2017-10-01

Chardonnay grape pomace was treated with pressurized heat followed by enzymatic hydrolysis, with commercial or pure enzymes, in buffered conditions. The pomace was unfermented as commonly found for white winemaking wastes and treatments aimed to simulate biovalorization processing. Cell wall profiling techniques showed that the pretreatment led to depectination of the outer layers thereby exposing xylan polymers and increasing the extractability of arabinans, galactans, arabinogalactan proteins and mannans. This higher extractability is believed to be linked with partial degradation and opening-up of cell wall networks. Pectinase-rich enzyme preparations were presumably able to access the inner rhamnogalacturonan I dominant coating layers due to the hydrothermal pretreatment. Patterns of epitope abundance and the sequential release of cell wall polymers with specific combinations of enzymes led to a working model of the hitherto, poorly understood innermost xyloglucan-rich hemicellulose layers of unfermented grape pomace. Copyright © 2017 Elsevier Ltd. All rights reserved.

Retention and chemical speciation of uranium in an oxidized wetland sediment from the Savannah River Site.

PubMed

Li, Dien; Seaman, John C; Chang, Hyun-Shik; Jaffe, Peter R; Koster van Groos, Paul; Jiang, De-Tong; Chen, Ning; Lin, Jinru; Arthur, Zachary; Pan, Yuanming; Scheckel, Kirk G; Newville, Matthew; Lanzirotti, Antonio; Kaplan, Daniel I

2014-05-01

Uranium speciation and retention mechanisms onto Savannah River Site (SRS) wetland sediments was studied using batch (ad)sorption experiments, sequential extraction, U L3-edge X-ray absorption near-edge structure (XANES) spectroscopy, fluorescence mapping and μ-XANES. Under oxidized conditions, U was highly retained by the SRS wetland sediments. In contrast to other similar but much lower natural organic matter (NOM) sediments, significant sorption of U onto the SRS sediments was observed at pH < 4 and pH > 8. Sequential extraction indicated that the U species were primarily associated with the acid soluble fraction (weak acetic acid extractable) and organic fraction (Na-pyrophosphate extractable). Uranium L3-edge XANES spectra of the U-bound sediments were nearly identical to that of uranyl acetate. Based on fluorescence mapping, U and Fe distributions in the sediment were poorly correlated, U was distributed throughout the sample and did not appear as isolated U mineral phases. The primary oxidation state of U in these oxidized sediments was U(VI), and there was little evidence that the high sorptive capacity of the sediments could be ascribed to abiotic or biotic reduction to the less soluble U(IV) species or to secondary mineral formation. Collectively, this study suggests that U may be strongly bound to wetland sediments, not only under reducing conditions by reductive precipitation, but also under oxidizing conditions through NOM-uranium bonding. Published by Elsevier Ltd.

Efficient sequential and parallel algorithms for finding edit distance based motifs.

PubMed

Pal, Soumitra; Xiao, Peng; Rajasekaran, Sanguthevar

2016-08-18

Motif search is an important step in extracting meaningful patterns from biological data. The general problem of motif search is intractable and there is a pressing need to develop efficient, exact and approximation algorithms to solve this problem. In this paper, we present several novel, exact, sequential and parallel algorithms for solving the (l,d) Edit-distance-based Motif Search (EMS) problem: given two integers l,d and n biological strings, find all strings of length l that appear in each input string with atmost d errors of types substitution, insertion and deletion. One popular technique to solve the problem is to explore for each input string the set of all possible l-mers that belong to the d-neighborhood of any substring of the input string and output those which are common for all input strings. We introduce a novel and provably efficient neighborhood exploration technique. We show that it is enough to consider the candidates in neighborhood which are at a distance exactly d. We compactly represent these candidate motifs using wildcard characters and efficiently explore them with very few repetitions. Our sequential algorithm uses a trie based data structure to efficiently store and sort the candidate motifs. Our parallel algorithm in a multi-core shared memory setting uses arrays for storing and a novel modification of radix-sort for sorting the candidate motifs. The algorithms for EMS are customarily evaluated on several challenging instances such as (8,1), (12,2), (16,3), (20,4), and so on. The best previously known algorithm, EMS1, is sequential and in estimated 3 days solves up to instance (16,3). Our sequential algorithms are more than 20 times faster on (16,3). On other hard instances such as (9,2), (11,3), (13,4), our algorithms are much faster. Our parallel algorithm has more than 600 % scaling performance while using 16 threads. Our algorithms have pushed up the state-of-the-art of EMS solvers and we believe that the techniques introduced in this paper are also applicable to other motif search problems such as Planted Motif Search (PMS) and Simple Motif Search (SMS).

Phytochemical Analysis and Free Radical Scavenging Activity of Medicinal Plants Gnidia glauca and Dioscorea bulbifera

PubMed Central

Ghosh, Sougata; Derle, Abhishek; Ahire, Mehul; More, Piyush; Jagtap, Soham; Phadatare, Suvarna D.; Patil, Ajay B.; Jabgunde, Amit M.; Sharma, Geeta K.; Shinde, Vaishali S.; Pardesi, Karishma; Dhavale, Dilip D.; Chopade, Balu A.

2013-01-01

Gnidia glauca and Dioscorea bulbifera are traditional medicinal plants that can be considered as sources of natural antioxidants. Herein we report the phytochemical analysis and free radical scavenging activity of their sequential extracts. Phenolic and flavonoid content were determined. Scavenging activity was checked against pulse radiolysis generated ABTS•+ and OH radical, in addition to DPPH, superoxide and hydroxyl radicals by biochemical methods followed by principal component analysis. G. glauca leaf extracts were rich in phenolic and flavonoid content. Ethyl acetate extract of D. bulbifera bulbs and methanol extract of G. glauca stem exhibited excellent scavenging of pulse radiolysis generated ABTS•+ radical with a second order rate constant of 2.33×106 and 1.72×106, respectively. Similarly, methanol extract of G. glauca flower and ethyl acetate extract of D. bulbifera bulb with second order rate constants of 4.48×106 and 4.46×106 were found to be potent scavengers of pulse radiolysis generated OH radical. G. glauca leaf and stem showed excellent reducing activity and free radical scavenging activity. HPTLC fingerprinting, carried out in mobile phase, chloroform: toluene: ethanol (4: 4: 1, v/v) showed presence of florescent compound at 366 nm as well as UV active compound at 254 nm. GC-TOF-MS analysis revealed the predominance of diphenyl sulfone as major compound in G. glauca. Significant levels of n-hexadecanoic acid and octadecanoic acid were also present. Diosgenin (C27H42O3) and diosgenin (3á,25R) acetate were present as major phytoconstituents in the extracts of D. bulbifera. G. glauca and D. bulbifera contain significant amounts of phytochemicals with antioxidative properties that can be exploited as a potential source for herbal remedy for oxidative stress induced diseases. These results rationalize further investigation in the potential discovery of new natural bioactive principles from these two important medicinal plants. PMID:24367520

Phytochemical analysis and free radical scavenging activity of medicinal plants Gnidia glauca and Dioscorea bulbifera.

PubMed

Ghosh, Sougata; Derle, Abhishek; Ahire, Mehul; More, Piyush; Jagtap, Soham; Phadatare, Suvarna D; Patil, Ajay B; Jabgunde, Amit M; Sharma, Geeta K; Shinde, Vaishali S; Pardesi, Karishma; Dhavale, Dilip D; Chopade, Balu A

2013-01-01

Gnidia glauca and Dioscorea bulbifera are traditional medicinal plants that can be considered as sources of natural antioxidants. Herein we report the phytochemical analysis and free radical scavenging activity of their sequential extracts. Phenolic and flavonoid content were determined. Scavenging activity was checked against pulse radiolysis generated ABTS(•+) and OH radical, in addition to DPPH, superoxide and hydroxyl radicals by biochemical methods followed by principal component analysis. G. glauca leaf extracts were rich in phenolic and flavonoid content. Ethyl acetate extract of D. bulbifera bulbs and methanol extract of G. glauca stem exhibited excellent scavenging of pulse radiolysis generated ABTS(•+) radical with a second order rate constant of 2.33 × 10(6) and 1.72 × 10(6), respectively. Similarly, methanol extract of G. glauca flower and ethyl acetate extract of D. bulbifera bulb with second order rate constants of 4.48 × 10(6) and 4.46 × 10(6) were found to be potent scavengers of pulse radiolysis generated OH radical. G. glauca leaf and stem showed excellent reducing activity and free radical scavenging activity. HPTLC fingerprinting, carried out in mobile phase, chloroform: toluene: ethanol (4: 4: 1, v/v) showed presence of florescent compound at 366 nm as well as UV active compound at 254 nm. GC-TOF-MS analysis revealed the predominance of diphenyl sulfone as major compound in G. glauca. Significant levels of n-hexadecanoic acid and octadecanoic acid were also present. Diosgenin (C₂₇H₄₂O₃) and diosgenin (3á,25R) acetate were present as major phytoconstituents in the extracts of D. bulbifera. G. glauca and D. bulbifera contain significant amounts of phytochemicals with antioxidative properties that can be exploited as a potential source for herbal remedy for oxidative stress induced diseases. These results rationalize further investigation in the potential discovery of new natural bioactive principles from these two important medicinal plants.

Comparison of the free and bound phenolic profiles and cellular antioxidant activities of litchi pulp extracts from different solvents

PubMed Central

2014-01-01

Background The phenolic contents and antioxidant activities of fruits could be underestimated if the bound phenolic compounds are not considered. In the present study, the extraction efficiencies of various solvents were investigated in terms of the total content of the free and bound phenolic compounds, as well as the phenolic profiles and antioxidant activities of the extracts. Methods Five different solvent mixtures were used to extract the free phenolic compounds from litchi pulp. Alkaline and acidic hydrolysis methods were compared for the hydrolysis of bound phenolic compounds from litchi pulp residue. The phenolic compositions of the free and bound fractions from the litchi pulp were identified using HPLC-DAD. The antioxidant activities of the litchi pulp extracts were determined by oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity (CAA) assays. Results Of the solvents tested, aqueous acetone extracted the largest amount of total free phenolic compounds (210.7 mg GAE/100 g FW) from litchi pulp, followed sequentially by aqueous mixtures of methanol, ethanol and ethyl acetate, and water itself. The acid hydrolysis method released twice as many bound phenolic compounds as the alkaline hydrolysis method. Nine phenolic compounds were detected in the aqueous acetone extract. In contrast, not all of these compounds were found in the other four extracts. The classification and content of the bound phenolic compounds released by the acid hydrolysis method were higher than those achieved by the alkaline hydrolysis. The aqueous acetone extract showing the highest ORAC value (3406.9 μmol TE/100 g FW) for the free phenolic extracts. For the CAA method, however, the aqueous acetone and methanol extracts (56.7 and 55.1 μmol QE/100 g FW) showed the highest levels of activity of the five extracts tested. The ORAC and CAA values of the bound phenolic compounds obtained by acid hydrolysis were 2.6- and 1.9-fold higher than those obtained using the alkaline hydrolysis method. Conclusions The free and bound phenolic contents and profiles and antioxidant activities of the extracts were found to be dependent on the extraction solvent used. Litchi exhibited good cellular antioxidant activity and could be a potentially useful natural source of antioxidants. PMID:24405977

Assessment of heavy metals bioavailability and toxicity toward Vibrio fischeri in sediment of the Huelva estuary.

PubMed

Rosado, Daniel; Usero, José; Morillo, José

2016-06-01

Relationship between toxicity and bioavailable metals in sediments from the Huelva estuary and its littoral of influence was analyzed. Toxicity was assessed with Microtox® bioassay using a marine luminescent bacterium: Vibrio fischeri. Bioavailable metals were considered as both, acid extractable fraction of BCR procedure and the sum of exchangeable and bound to carbonates fractions of Tessier sequential extraction. A bioavailable metals index was calculated to integrate results in a single figure. Toxicity and bioavailable metals showed a similar pattern. Higher levels were found in the estuary than in the littoral (140 TU/g). In Huelva estuary, highest levels were found in the Tinto estuary (5725 TU/g), followed by the Odiel estuary (5100 TU/g) and the Padre Santo Canal (2500 TU/g). Results in this area were well over than those in nearby estuaries. Furthermore, they are similar to or even higher than those in other polluted sediments around the world. Bioavailable metal index showed a stronger correlation with acid extractable fraction of BCR (R(2) = 0.704) than that for the sum of exchangeable and bound to carbonates fractions of Tessier (R(2) = 0.661). These results suggest that bioavailable metals are an important source of sediment toxicity in the Huelva estuary and its littoral of influence, an area with one of the highest mortality risks of Spain. Copyright © 2016 Elsevier Ltd. All rights reserved.

Polyphenols in the woody roots of Norway spruce and European beech reduce TTC.

PubMed

Richter, Anika K; Frossard, Emmanuel; Brunner, Ivano

2007-01-01

A common method to determine the vitality of fine root tissue is the measurement of respiratory activity with triphenyltetrazolium chloride (TTC). The colorless TTC is reduced to the red-colored triphenyl formazan (TF) as a result of the dehydrogenase activity of the mitochondrial respiratory chain. However, measurements with woody fine roots of adult Norway spruce and European beech trees showed that dead control roots had a high potential to react with TTC. High reactivity was found in boiled fine roots and the bark of coarse roots, but not in the boiled wood of coarse roots. By sequential extraction of dried and ground adult Norway spruce fine roots, reactivity with TTC was reduced by about 75% (water extraction), 93% (water/methanol extraction) and 94% (water/acetone extraction). The water extract reacted with TTC in the same way as polyphenols such as lignin, catechin and epicatechin. Boiling did not affect the extent to which fine roots of adult trees reduced TTC, whereas it greatly reduced TTC reduction by seedling roots. Application of the TTC test to roots of spruce seedlings subjected to increasing drought showed a progressive decrease in TTC reduction. The decrease in TTC reduction was paralleled by a reduction in O(2) consumption, thus supporting the conclusion that for roots with a low polyphenol content the TTC test provides a valid assessment of tissue vitality. Our results suggest, however, that the TTC test should not be applied to the fine roots of adult trees because of their high content of polyphenolic compounds whose reaction with TTC masks changes in TTC reduction due to changes in the respiratory capacity of the tissue.

Distribution and mode of occurrence of radionuclides in phosphogypsum derived from Aqaba and Eshidiya Fertilizer Industry, South Jordan

USGS Publications Warehouse

Al-Hwaiti, M. S.; Zielinski, R.A.; Bundham, J.R.; Ranville, J.F.; Ross, P.E.

2010-01-01

Phosphogypsum (PG) is a by-product of the chemical reaction called the "wet process" whereby sulphuric acid reacts with phosphate rock (PR) to produce phosphoric acid, needed for fertilizer production. Through the wet process, some impurities naturally present in the PR become incorporated in PG, including U decay-series radionuclides, are the main important concern which could have an effect on the surrounding environment and prevent its safe utilization. In order to determine the distribution and bioavailability of radionuclides to the surrounding environment, we used a sequential leaching of PG samples from Aqaba and Eshidiya fertilizer industry. The results showed that the percentages of 226Ra and 210Pb in PG are over those in the corresponding phosphate rocks (PG/PR), where 85% of the 226Ra and 85% of the 210Pb fractionate to PG. The sequential extraction results exhibited that most of 226Ra and 210Pb are bound in the residual phase (non-CaSO4) fraction ranging from 45-65% and 55%-75%, respectively, whereas only 10%-15% and 10%-20% respectively of these radionuclides are distributed in the most labile fraction. The results obtained from this study showed that radionuclides are not incorporated with gypsum itself and may not form a threat to the surrounding environment. ?? 2010 Science Press, Institute of Geochemistry, CAS and Springer Berlin Heidelberg.

Metabolic routes along digestive system of licorice: multicomponent sequential metabolism method in rat.

PubMed

Zhang, Lei; Zhao, Haiyu; Liu, Yang; Dong, Honghuan; Lv, Beiran; Fang, Min; Zhao, Huihui

2016-06-01

This study was conducted to establish the multicomponent sequential metabolism (MSM) method based on comparative analysis along the digestive system following oral administration of licorice (Glycyrrhiza uralensis Fisch., leguminosae), a traditional Chinese medicine widely used for harmonizing other ingredients in a formulae. The licorice water extract (LWE) dissolved in Krebs-Ringer buffer solution (1 g/mL) was used to carry out the experiments and the comparative analysis was performed using HPLC and LC-MS/MS methods. In vitro incubation, in situ closed-loop and in vivo blood sampling were used to measure the LWE metabolic profile along the digestive system. The incubation experiment showed that the LWE was basically stable in digestive juice. A comparative analysis presented the metabolic profile of each prototype and its corresponding metabolites then. Liver was the major metabolic organ for LWE, and the metabolism by the intestinal flora and gut wall was also an important part of the process. The MSM method was practical and could be a potential method to describe the metabolic routes of multiple components before absorption into the systemic blood stream. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Gene expression profiling gut microbiota in different races of humans

NASA Astrophysics Data System (ADS)

Chen, Lei; Zhang, Yu-Hang; Huang, Tao; Cai, Yu-Dong

2016-03-01

The gut microbiome is shaped and modified by the polymorphisms of microorganisms in the intestinal tract. Its composition shows strong individual specificity and may play a crucial role in the human digestive system and metabolism. Several factors can affect the composition of the gut microbiome, such as eating habits, living environment, and antibiotic usage. Thus, various races are characterized by different gut microbiome characteristics. In this present study, we studied the gut microbiomes of three different races, including individuals of Asian, European and American races. The gut microbiome and the expression levels of gut microbiome genes were analyzed in these individuals. Advanced feature selection methods (minimum redundancy maximum relevance and incremental feature selection) and four machine-learning algorithms (random forest, nearest neighbor algorithm, sequential minimal optimization, Dagging) were employed to capture key differentially expressed genes. As a result, sequential minimal optimization was found to yield the best performance using the 454 genes, which could effectively distinguish the gut microbiomes of different races. Our analyses of extracted genes support the widely accepted hypotheses that eating habits, living environments and metabolic levels in different races can influence the characteristics of the gut microbiome.

Gene expression profiling gut microbiota in different races of humans

PubMed Central

Chen, Lei; Zhang, Yu-Hang; Huang, Tao; Cai, Yu-Dong

2016-01-01

The gut microbiome is shaped and modified by the polymorphisms of microorganisms in the intestinal tract. Its composition shows strong individual specificity and may play a crucial role in the human digestive system and metabolism. Several factors can affect the composition of the gut microbiome, such as eating habits, living environment, and antibiotic usage. Thus, various races are characterized by different gut microbiome characteristics. In this present study, we studied the gut microbiomes of three different races, including individuals of Asian, European and American races. The gut microbiome and the expression levels of gut microbiome genes were analyzed in these individuals. Advanced feature selection methods (minimum redundancy maximum relevance and incremental feature selection) and four machine-learning algorithms (random forest, nearest neighbor algorithm, sequential minimal optimization, Dagging) were employed to capture key differentially expressed genes. As a result, sequential minimal optimization was found to yield the best performance using the 454 genes, which could effectively distinguish the gut microbiomes of different races. Our analyses of extracted genes support the widely accepted hypotheses that eating habits, living environments and metabolic levels in different races can influence the characteristics of the gut microbiome. PMID:26975620

Analysis of Optimal Sequential State Discrimination for Linearly Independent Pure Quantum States.

PubMed

Namkung, Min; Kwon, Younghun

2018-04-25

Recently, J. A. Bergou et al. proposed sequential state discrimination as a new quantum state discrimination scheme. In the scheme, by the successful sequential discrimination of a qubit state, receivers Bob and Charlie can share the information of the qubit prepared by a sender Alice. A merit of the scheme is that a quantum channel is established between Bob and Charlie, but a classical communication is not allowed. In this report, we present a method for extending the original sequential state discrimination of two qubit states to a scheme of N linearly independent pure quantum states. Specifically, we obtain the conditions for the sequential state discrimination of N = 3 pure quantum states. We can analytically provide conditions when there is a special symmetry among N = 3 linearly independent pure quantum states. Additionally, we show that the scenario proposed in this study can be applied to quantum key distribution. Furthermore, we show that the sequential state discrimination of three qutrit states performs better than the strategy of probabilistic quantum cloning.

Assessment of soil stabilization by chemical extraction and bioaccumulation using earthworm, Eisenia fetida

NASA Astrophysics Data System (ADS)

Lee, Byung-Tae; Abd Aziz, Azilah; Han, Heop Jo; Kim, Kyoung-Woong

2014-05-01

Soil stabilization does not remove heavy metals from contaminated soil, but lowers their exposures to ecosystem. Thus, it should be evaluated by measuring the fractions of heavy metals which are mobile and/or bioavailable in soils. The study compared several chemical extractions which intended to quantify the mobile or bioaccessible fractions with uptake and bioaccumulation by earthworm, Eisenia fetida. Soil samples were taken from the abandoned mine area contaminated with As, Cd, Cu, Pb and/or Zn. To stabilize heavy metals, the soils were amended with limestone and steel slag at 5% and 2% (w/w), respectively. All chemical extractions and earthworm tests were applied to both the contaminated and the stabilized soils with triplicates. The chemical extractions consisted of six single extractions which were 0.01M CaCl2 (unbufferred), EDTA or DTPA (chelating), TCLP (acidic), Mehlich 3 (mixture), and aqua regia (peudo-total). Sequential extractions were also applied to fractionate heavy metals in soils. In earthworm tests, worms were exposed to the soils for uptake of heavy metals. After 28 days of exposure to soils, worms were transferred to clean soils for elimination. During the tests, three worms were randomly collected at proper sampling events. Worms were rinsed with DI water and placed on moist filter paper for 48 h for depuration. Filter paper was renewed at 24 h to prevent coprophagy. The worms were killed with liquid nitrogen, dried in the oven, and digested with aqua regia for ICP-MS analysis. In addition to the bioaccumulation, several toxicity endpoints were observed such as burrowing time, mortality, cocoon production, and body weight changes. Toxicokinetics was applied to determine the uptake and elimination heavy metals by the earthworms. Bioaccumulation factor (BAF) was estimated using total metal concentrations and body burdens. Pearson correlation and simple linear regression were applied to evaluate the relationship between metal fractions by single extractions or sequential extractions with bioaccumulations. Finally, we discussed the advantages or disadvantages of simple chemical extractions which are commonly used to estimate the efficacy of stabilization.

The effectiveness of municipal sewage sludge application on the stabilization of Pb, Zn, and Cd in a soil contaminated from mining activities.

PubMed

Xenidis, A; Stouraiti, C; Moirou, A

2001-01-01

The effectiveness of municipal sewage sludge for the stabilisation of Pb, Zn and Cd in a heavily contaminated soil was evaluated by performing pot experiments on soil-sludge mixtures. The soil sample originated from the Montevecchio mining district, Sardinia, Italy, and presented high Pb, Zn and Cd content, as well as US EPA TCLP solubility values for Pb and Cd, which exceeded the respective regulatory limits. Sewage sludge application increased the soil pH. Stabilisation experiments showed that 10% w/w sewage sludge addition effectively reduced Pb and Cd solubilities below the TCLP regulatory limits. At the same addition rate, the EDTA extractable fraction of Pb, Zn, Cd in the treated soil was reduced by 12, 47 and 50% respectively compared with the untreated sample. The five-stage sequential extraction procedure applied on the untreated and treated soil samples, showed a remarkable shift of the metals towards more stable forms. The reducible fractions of Zn and Cd and the residual fraction of Pb were increased by 12, 20 and 18% respectively, while a corresponding decrease in the mobile fractions (exchangeable and carbonate) occurred which accounted for 14, 23 and 25% respectively.

Mineralogy and geochemistry of a Late Permian coal in the Dafang Coalfield, Guizhou, China: Influence from siliceous and iron-rich calcic hydrothermal fluids

USGS Publications Warehouse

Dai, S.; Chou, C.-L.; Yue, M.; Luo, K.; Ren, D.

2005-01-01

This paper describes the influence of siliceous and iron-rich calcic low-temperature hydrothermal fluids (LTHF) on the mineralogy and geochemistry of the Late Permian No. 11 Coal (anthracitic, Rr =2.85%) in the Dafang Coalfield in northwestern Guizhou Province, China. The No. 11 Coal has high contents of vein ankerite (10.2 vol.%) and vein quartz (11.4 vol.%), with formation temperatures of 85 and 180 ??C, respectively, indicating that vein ankerite and vein quartz were derived from low-temperature calcic and siliceous hydrothermal fluids in two epigenetic episodes. The vein quartz appears to have formed earlier than vein ankerite did, and at least three distinct stages of ankerite formation with different Ca/Sr and Fe/Mn ratios were observed. The two types of mineral veins are sources of different suites of major and trace metals. Scanning electron microscope and sequential extraction studies show that, in addition to Fe, Mg, and Ca, vein ankerite is the dominant source of Mn, Cu, Ni, Pb, and Zn in the coal, and the contents of these five elements are as high as 0.09% and 74.0, 33.6, 185, and 289 ??g/g, respectively. In contrast, vein quartz is the main carrier mineral for platinum-group elements (PGEs) Pd, Pt, and Ir in the coal, and the contents of Pd, Pt, and Ir are 1.57, 0.15, and 0.007 ??g/g, respectively. Sequential extraction showed a high PGE content in the silicate fraction, up to 10.4 ??g/g Pd, 1.23 ??g/g Pt, and 0.05 ??g/g Ir, respectively. It is concluded that the formation of ankerite and quartz and the anomalous enrichment of trace elements in the No. 11 Coal in the Dafang Coalfield, Guizhou, result from the influx of calcic and siliceous low-temperature hydrothermal fluids. ?? 2004 Elsevier B.V. All rights reserved.

Effect of nanohydroxyapatite on cadmium leaching and environmental risks under simulated acid rain.

PubMed

Zhao, Chenchen; Ren, Shuxia; Zuo, Qingqing; Wang, Shutao; Zhou, Yapeng; Liu, Wei; Liang, Shuxuan

2018-06-15

Cadmium (Cd) contamination in soil is a global environmental pollution issue. Nanohydroxyapatite (NHAP) has been used in soil remediation to immobilize cadmium in contaminated soils. However, the effect of acid rain on the export of cadmium from topsoil and its behavior in deep soil and leachate is unclear. In this study, column experiments and development of parsimonious model were performed to estimate Cd leaching behavior from topsoil and environmental risk of groundwater after 0.5% NHAP remediation. Four leaching events were performed and total Cd, different fractions of Cd determined by sequential extraction procedure and pH were determined for each leaching. The results show that with the export of Cd in topsoil, the total Cd concentration in soil at different depths had the following vertical distributions: 0-5 cm > 5-10 cm > 10-15 cm > 15-20 cm. NHAP treatment increased the soil pH and decreased Cd leaching loss by 56.45% compared to the control, and the results fit the parabolic diffusion model. With sequential extraction it was observed that NHAP application increased the residual fraction of cadmium in soil. After leaching, there was a positive correlation between soil pH and Cd concentration with regards to the exchangeable, reducible, oxidizable and residual Cd fractions. The parabolic diffusion model showed that Cd-contaminated soil with NHAP remediation is harmless to humans after sufficient remediation duration, whereas the resultant concentrations from the CK treatment could be toxic. The results indicate that nanohydroxyapatite could significantly reduce the bioavailability of cadmium and the environmental risk. However, the release of Ca and P from the dissolution of NHAP should be carefully studied as this will impact the mobilization of Cd or colloid Cd, and high leaching of P may result in P-induced eutrophication risk. Copyright © 2018 Elsevier B.V. All rights reserved.

Determining the speciation of Zn in soils around the sediment ponds of chemical plants by XRD and XAFS spectroscopy and sequential extraction.

PubMed

Minkina, Tatiana; Nevidomskaya, Dina; Bauer, Tatiana; Shuvaeva, Victoria; Soldatov, Alexander; Mandzhieva, Saglara; Zubavichus, Yan; Trigub, Alexander

2018-09-01

For a correct assessment of risk of polluted soil, it is crucial to establish the speciation and mobility of the contaminants. The aim of this study was to investigate the speciation and transformation of Zn in strongly technogenically transformed contaminated Spolic Technosols for a long time in territory of sludge collectors by combining analytical techniques and synchrotron techniques. Sequential fractionation of Zn compounds in studied soils revealed increasing metal mobility. Phyllosilicates and Fe and Mn hydroxides were the main stabilizers of Zn mobility. A high degree of transformation was identified for the composition of the mineral phase in Spolic Technosols by X-ray powder diffraction. Technogenic phases (Zn-containing authigenic minerals) were revealed in Spolic Technosols samples through the analysis of their Zn K-edge EXAFS and XANES spectra. In one of the samples Zn local environment was formed by predominantly oxygen atoms, and in the other one mixed ZnS and ZnO bonding was found. Zn speciation in the studied technogenically transformed soils was due to the composition of pollutants contaminating the floodplain landscapes for a long time, and, second, this is the combination of physicochemical properties controlling the buffer properties of investigated soils. X-ray spectroscopic and X-ray powder diffraction analyses combined with sequential extraction assays is an effective tool to check the affinity of the soil components for heavy metal cations. Copyright © 2018 Elsevier B.V. All rights reserved.

Field-scale multi-phase LNAPL remediation: Validating a new computational framework against sequential field pilot trials.

PubMed

Sookhak Lari, Kaveh; Johnston, Colin D; Rayner, John L; Davis, Greg B

2018-03-05

Remediation of subsurface systems, including groundwater, soil and soil gas, contaminated with light non-aqueous phase liquids (LNAPLs) is challenging. Field-scale pilot trials of multi-phase remediation were undertaken at a site to determine the effectiveness of recovery options. Sequential LNAPL skimming and vacuum-enhanced skimming, with and without water table drawdown were trialled over 78days; in total extracting over 5m 3 of LNAPL. For the first time, a multi-component simulation framework (including the multi-phase multi-component code TMVOC-MP and processing codes) was developed and applied to simulate the broad range of multi-phase remediation and recovery methods used in the field trials. This framework was validated against the sequential pilot trials by comparing predicted and measured LNAPL mass removal rates and compositional changes. The framework was tested on both a Cray supercomputer and a cluster. Simulations mimicked trends in LNAPL recovery rates (from 0.14 to 3mL/s) across all remediation techniques each operating over periods of 4-14days over the 78day trial. The code also approximated order of magnitude compositional changes of hazardous chemical concentrations in extracted gas during vacuum-enhanced recovery. The verified framework enables longer term prediction of the effectiveness of remediation approaches allowing better determination of remediation endpoints and long-term risks. Copyright © 2017 Commonwealth Scientific and Industrial Research Organisation. Published by Elsevier B.V. All rights reserved.

Method of Real-Time Principal-Component Analysis

NASA Technical Reports Server (NTRS)

Duong, Tuan; Duong, Vu

2005-01-01

Dominant-element-based gradient descent and dynamic initial learning rate (DOGEDYN) is a method of sequential principal-component analysis (PCA) that is well suited for such applications as data compression and extraction of features from sets of data. In comparison with a prior method of gradient-descent-based sequential PCA, this method offers a greater rate of learning convergence. Like the prior method, DOGEDYN can be implemented in software. However, the main advantage of DOGEDYN over the prior method lies in the facts that it requires less computation and can be implemented in simpler hardware. It should be possible to implement DOGEDYN in compact, low-power, very-large-scale integrated (VLSI) circuitry that could process data in real time.

Infiltration Processes and Flow Velocities Across the Landscape: When and Where is Macropore Flow Relevant?

NASA Astrophysics Data System (ADS)

Demand, D.; Blume, T.; Weiler, M.

2017-12-01

Preferential flow in macropores significantly affects the distributions of water and solutes in soil and many studies showed its relevance worldwide. Although some models include this process as a second pore domain, little is known about the spatial patterns and temporal dynamics. For example, while flow in the matrix is usually modeled and parameterized based on soil texture, an influence of texture on non-capillary flow for a given land-use class is poorly understood. To investigate the temporal and spatial dynamics on preferential flow we used a four-year soil moisture dataset from the mesoscale Attert catchment (288 km²) in Luxembourg. This dataset contains time series from 126 soil profiles in different textures and two land-use classes (forest, grassland). The soil moisture probes were installed in 10, 30 and 50 cm depth and measured in a 5-minute temporal resolution. Events were defined by a soil moisture increase higher than the instrument noise after a precipitation sum of more than 1 mm. Precipitation was measured next to the profiles so that each location could be associated to its unique precipitation characteristics. For every event and profile the soil moisture reaction was classified in sequential (ordered by depth) and non-sequential response. A non-sequential soil moisture reaction was used as an indicator of preferential flow. For sequential flow, the velocity was determined by the first reaction between two vertically adjacent sensors. The sensor reaction and wetting front velocity was analyzed in the context of precipitation characteristics and initial soil water content. Grassland sites showed a lower proportion of non-sequential flow than forest sites. For forest, non-sequential response is dependent on texture, rainfall intensity and initial water content. This is less distinct for the grassland sites. Furthermore, sequential reactions show higher flow velocities at sites, which also have high percentage of non-sequential response. In contrast, grassland sites show a more homogenous wetting front independent of soil texture. Compared against common modelling approaches of soil water flow, measured velocities show clear evidence of preferential flow, especially for forest soils. The analysis also shows that vegetation can alter the soil properties above the textural properties alone.

Long-term batch study of sorption, transformation and extractability to characterize the fate of the veterinary antibiotic sulfadiazine

NASA Astrophysics Data System (ADS)

Sittig, Stephan; Kasteel, Roy; Groeneweg, Joost; Vereecken, Harry

2010-05-01

The occurrence of veterinary antibiotic substances in various environmental compartments is of growing concern. Once released into the environment (e.g. via manure), these organic substances can cause changes in the composition of microbial populations, provoke the development and spreading of resistance genes and finally reach the food chain. The substance under study is the veterinary antibiotic sulfadiazine (SDZ), which belongs to the chemical group of the sulfonamides. These compounds are widely applied in animal husbandry. There are hardly any studies on the macroscopic sorption and desorption behaviour in combination with transformation processes, particularly investigating the sorbed fraction. We are conducting long-term batch sorption experiments to characterize the partitioning between the liquid and the solid phases as well as formation of transformation products. A sequential extraction procedure enables us to analyse the composition of the various sorbed fractions. We applied 14C-labelled SDZ in aqueous solution to fresh soil, originating from an agricultural field (silty loam). Adsorption and desorption studies are conducted for the duration of 60 d and 80 d, respectively. Unique setups for single time-steps allow us to trace the development of the partition process between the liquid and the solid phase and also partitioning within the solid phase. The composition of these liquid phases concerning the parent substance and the transformation products is analyzed. Using Radio-HPLC we find at least five transformation products: 4-hydroxy-sulfadiazine (4-OH-SDZ), 4-(2-iminopyrimidin-1(2H)-yl)-aniline (An-SDZ) and additionally three yet unknown products. By means of a sequential extraction, differently strong bound fractions of the compound can be distinguished. Extractions consist of a mild method (0.01 M CaCl2-solution; 24 h) followed by a methanol extraction (4 h). Finally, a residual fraction is gained by microwave extraction at an elevated temperature (150°C) and pressure (mixture of water and acetonitril, 4:1). Bound residues are determined by combustion. The course of the kinetic adsorption/desorption processes as well as the partitioning of the compound over the various solid phase fractions is observed. Sorption is time-dependent and strongly non-linear. The topsoil shows a significantly higher sorption affinity than the subsoil. While the amount of radioactivity sorbed to the soil matrix increases with time, the extractability decreases significantly, i. e. at the end of the experimental time there is no yield with mild extraction methods. On the contrary, after 60 d, there is still a considerably mass gained with the microwave extraction. Desorption is very slow due to hysteresis. In the topsoil transformation occurs with higher rates, leading to more detectable transformation products as in the subsoil. With our experimental setup it will be possible to set up a kinetic modell for the partitioning of the solute between the liquid and the solid phase. This description will also include an estimation of the transformation parameters.

Back-extraction of trace elements from organometallic-halide extracts for determination by flameless atomic absorption spectrometry

USGS Publications Warehouse

Clark, J.R.; Viets, J.G.

1981-01-01

The Methyl isobutyl ketone-Amine synerGistic Iodkte Complex (MAGIC) extraction system offers the advantage that a large number of trace elements can be rapidly determined with a single sample preparation procedure. However, many of the elements extracted by the MAGIC system form volatile organometallic halide salts when the organic extract is heated in the graphite furnace. High concentrations of some elements such as Cu and Zn extracted by the system from anomalous geological samples produce serious interferences when certain other elements are determined by flameless atomic absorption. Stripping systems have been developed using solutions of HNO3, H2SO4, and CH3COOH individually or combined with H2O2 in order to circumvent these problems. With these systems most of the elements in the organic extract can be sequentially stripped into an aqueous phase. Organometallic volatilization and the most serious interelement interferences, therefore, can be eliminated by stripping with various combinations of reagents in a series of steps.

Sequential single shot X-ray photon correlation spectroscopy at the SACLA free electron laser

DOE PAGES

Lehmkühler, Felix; Kwaśniewski, Paweł; Roseker, Wojciech; ...

2015-11-27

In this study, hard X-ray free electron lasers allow for the first time to access dynamics of condensed matter samples ranging from femtoseconds to several hundred seconds. In particular, the exceptional large transverse coherence of the X-ray pulses and the high time-averaged flux promises to reach time and length scales that have not been accessible up to now with storage ring based sources. However, due to the fluctuations originating from the stochastic nature of the self-amplified spontaneous emission (SASE) process the application of well established techniques such as X-ray photon correlation spectroscopy (XPCS) is challenging. Here we demonstrate a single-shotmore » based sequential XPCS study on a colloidal suspension with a relaxation time comparable to the SACLA free-electron laser pulse repetition rate. High quality correlation functions could be extracted without any indications for sample damage. This opens the way for systematic sequential XPCS experiments at FEL sources.« less

Sequential single shot X-ray photon correlation spectroscopy at the SACLA free electron laser

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

Lehmkühler, Felix; Kwaśniewski, Paweł; Roseker, Wojciech

In this study, hard X-ray free electron lasers allow for the first time to access dynamics of condensed matter samples ranging from femtoseconds to several hundred seconds. In particular, the exceptional large transverse coherence of the X-ray pulses and the high time-averaged flux promises to reach time and length scales that have not been accessible up to now with storage ring based sources. However, due to the fluctuations originating from the stochastic nature of the self-amplified spontaneous emission (SASE) process the application of well established techniques such as X-ray photon correlation spectroscopy (XPCS) is challenging. Here we demonstrate a single-shotmore » based sequential XPCS study on a colloidal suspension with a relaxation time comparable to the SACLA free-electron laser pulse repetition rate. High quality correlation functions could be extracted without any indications for sample damage. This opens the way for systematic sequential XPCS experiments at FEL sources.« less

Smart Occupancy Sensor Debuts - Continuum Magazine | NREL

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occupancy, IPOS uses sequential image subtractions like this one for extracting and analyzing motion building energy performance. Noted as one of the 100 most significant innovations of 2013 by R&D device where one edge of the IC is exposed. In the background is a blackboard on which computer

PATTERN RECOGNITION APPROACH TO MEDICAL DIAGNOSIS,

DTIC Science & Technology

A sequential method of pattern recognition was used to recognize hyperthyroidism in a sample of 2219 patients being treated at the Straub Clinic in...the most prominent class features are selected. Thus, the symptoms which best distinguish hyperthyroidism are extracted at every step and the number of tests required to reach a diagnosis is reduced. (Author)

Arsenic release from arsenopyrite weathering: insights from sequential extraction and microscopic studies.

PubMed

Basu, Ankan; Schreiber, Madeline E

2013-11-15

At a former As mine site, arsenopyrite oxidation has resulted in formation of scorodite and As-bearing iron hydroxide, both in host rock and mine tailings. Electron microprobe analysis documents that arsenopyrite weathers along two pathways: one that involves formation of sulfur, and one that does not. In both pathways, arsenopyrite oxidizes to form scorodite, which dissolves incongruently to form As-bearing iron hydroxides. From a mass balance perspective, arsenopyrite oxidation to scorodite conserves As, but as scorodite dissolves incongruently to iron hydroxides, As is released to solution, resulting in elevated As concentrations in the headwater stream adjacent to the site. The As-bearing iron hydroxide is the dominant solid phase reservoir of As in mine tailings and stream sediment, as suggested by sequential extraction. This As-bearing iron hydroxide is stable under the aerobic and pH 4-6 conditions at the site; however, changes in biogeochemical conditions resulting from sediment burial or future remedial efforts, which could promote As release from this reservoir due to reductive dissolution, should be avoided. Copyright © 2012 Elsevier B.V. All rights reserved.

Study on demetalization of sewage sludge by sequential extraction before liquefaction for the production of cleaner bio-oil and bio-char.

PubMed

Leng, Lijian; Yuan, Xingzhong; Shao, Jianguang; Huang, Huajun; Wang, Hou; Li, Hui; Chen, Xiaohong; Zeng, Guangming

2016-01-01

Demetalization of sewage sludge (SS) by sequential extraction before liquefaction was implemented to produce cleaner bio-char and bio-oil. Demetalization steps 1 and 2 did not cause much organic matter loss on SS, and thus the bio-oil and bio-char yields and the compositions of bio-oils were also not affected significantly. However, the demetalization procedures resulted in the production of cleaner bio-chars and bio-oils. The total concentrations and the acid soluble/exchangeable fraction (F1 fraction, the most toxic heavy metal fraction) of heavy metals (Cu, Cr, Pb, Zn, and Cd) in these products were significantly reduced and the environmental risks of these products were also relived considerably compared with those produced from raw SS, respectively. Additionally, these bio-oils had less heavy fractions. Demetalization processes with removal of F1 and F2 fractions of heavy metals would benefit the production of cleaner bio-char and bio-oil by liquefaction of heavy metal abundant biomass like SS. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluating the Mobility of Arsenic in Synthetic Iron-containing Solids Using a Modified Sequential Extraction Method

PubMed Central

Shan, Jilei; Sáez, A. Eduardo; Ela, Wendell P.

2013-01-01

Many water treatment technologies for arsenic removal that are used today produce arsenic-bearing residuals which are disposed in non-hazardous landfills. Previous works have established that many of these residuals will release arsenic to a much greater extent than predicted by standard regulatory leaching tests (e.g. the toxicity characteristic leaching procedure, TCLP) and, consequently, require stabilization to ensure benign behavior after disposal. In this work, a four-step sequential extraction method was developed in an effort to determine the proportion of arsenic in various phases in untreated as well as stabilized iron-based solid matrices. The solids synthesized using various potential stabilization techniques included: amorphous arsenic-iron sludge (ASL), reduced ASL via reaction with zero valent iron (RASL), amorphous ferrous arsenate (PFA), a mixture of PFA and SL (M1), crystalline ferrous arsenate (HPFA), and a mixture of HPFA and SL (M2). The overall arsenic mobility of the tested samples increased in the following order: ASL > RASL > PFA > M1 > HPFA > M2. PMID:23459695

Enrichment desired quality chitosan fraction and advance yield by sequential static and static-dynamic supercritical CO2.

PubMed

Hsieh, Yi-Yin; Chin, Hui Yen; Tsai, Min-Lang

2015-11-20

This study aimed to establish the sequential static and static-dynamic supercritical carbon dioxide (SDCO2) fractionation conditions to obtain a higher yield and desired chitosan with lower polydispersity index (PDI) and higher degree of deacetylation (DD). The yield increased with increasing DD of used chitosan and amount of cosolvent. The yield of acetic acid cosolvent was higher than those of malic and citric acid cosolvents. SDCO2, compared to static supercritical carbon dioxide, has higher yield. The yield of extracted chitosan was 5.82-14.70% by SDCO2/acetic acid, which increases with increasing pressure. The DD of fractionated chitosan increased from 66.1% to 70.81-85.33%, while the PDI decreased from 3.97 to 1.69-3.16. The molecular weight changed from 622kDa to 412-649kDa, which increased as density of supercritical carbon dioxide increases. Hence, higher DD and lower PDI extracted chitosan can be obtained through controlling the temperature and pressure of SDCO2. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sequential Total Variation Denoising for the Extraction of Fetal ECG from Single-Channel Maternal Abdominal ECG

PubMed Central

Lee, Kwang Jin; Lee, Boreom

2016-01-01

Fetal heart rate (FHR) is an important determinant of fetal health. Cardiotocography (CTG) is widely used for measuring the FHR in the clinical field. However, fetal movement and blood flow through the maternal blood vessels can critically influence Doppler ultrasound signals. Moreover, CTG is not suitable for long-term monitoring. Therefore, researchers have been developing algorithms to estimate the FHR using electrocardiograms (ECGs) from the abdomen of pregnant women. However, separating the weak fetal ECG signal from the abdominal ECG signal is a challenging problem. In this paper, we propose a method for estimating the FHR using sequential total variation denoising and compare its performance with that of other single-channel fetal ECG extraction methods via simulation using the Fetal ECG Synthetic Database (FECGSYNDB). Moreover, we used real data from PhysioNet fetal ECG databases for the evaluation of the algorithm performance. The R-peak detection rate is calculated to evaluate the performance of our algorithm. Our approach could not only separate the fetal ECG signals from the abdominal ECG signals but also accurately estimate the FHR. PMID:27376296

Sequential Total Variation Denoising for the Extraction of Fetal ECG from Single-Channel Maternal Abdominal ECG.

PubMed

Lee, Kwang Jin; Lee, Boreom

2016-07-01

Fetal heart rate (FHR) is an important determinant of fetal health. Cardiotocography (CTG) is widely used for measuring the FHR in the clinical field. However, fetal movement and blood flow through the maternal blood vessels can critically influence Doppler ultrasound signals. Moreover, CTG is not suitable for long-term monitoring. Therefore, researchers have been developing algorithms to estimate the FHR using electrocardiograms (ECGs) from the abdomen of pregnant women. However, separating the weak fetal ECG signal from the abdominal ECG signal is a challenging problem. In this paper, we propose a method for estimating the FHR using sequential total variation denoising and compare its performance with that of other single-channel fetal ECG extraction methods via simulation using the Fetal ECG Synthetic Database (FECGSYNDB). Moreover, we used real data from PhysioNet fetal ECG databases for the evaluation of the algorithm performance. The R-peak detection rate is calculated to evaluate the performance of our algorithm. Our approach could not only separate the fetal ECG signals from the abdominal ECG signals but also accurately estimate the FHR.

The effect of aging on sequestration and bioaccessibility of oxytetracycline in soils.

PubMed

Liu, Yuxia; Bao, Yanyu; Cai, Zhang; Zhang, Zhenzihao; Cao, Peilin; Li, Xinqian; Zhou, Qixing

2015-07-01

Veterinary antibiotics introduced into soil environment may change the composition and functioning of soil microbial communities and promote the spreading of antibiotic resistance. Actual risks depend on the antibiotic's bioaccessibility and sequestration in soils, which may vary with contact time and soil properties. We elucidated changes in the horsebean plant's bioaccessible oxytetracycline with increasing contact time in three different soils (cinnamon, red, and brown soil) and observed discrepancy in oxytetracycline dissipation using sequential extractions with H2O-, 0.01 M CaCl2-, and Mcllvaine- in the same three soils. The results showed lower quantities of oxytetracycline with increasing contact time over 20 days than the level in freshly contaminated soils but hugely discrepant quantities among the three tested soils. In addition, aging largely reduced dissipation of H2O-, 0.01 M CaCl2-, and Mcllvaine- extracted oxytetracycline in soils before planting. However, bioturbation helped increase the H2O-, CaCl2-, and Mcllvaine- extracted oxytetracyline from cinnamon and brown soils with aging. Lastly, correlation analysis indicated that bioaccessibility of oxytetracycline significantly correlates with the total of H2O-, CaCl2-, and Mcllvaine- extracted oxytetracycline (0.676**, p < 0.01) in soils, especially the H2O- (0.789**, p < 0.01) and Mcllvaine- (0.686**, p < 0.01) extracted oxytetracycline with aging. Overall, this study provides some basic understanding of the aging effect on sequestration and bioaccessibility of veterinary antibiotics in soils.

Sequential contrast-enhanced MR imaging of the penis.

PubMed

Kaneko, K; De Mouy, E H; Lee, B E

1994-04-01

To determine the enhancement patterns of the penis at magnetic resonance (MR) imaging. Sequential contrast material-enhanced MR images of the penis in a flaccid state were obtained in 16 volunteers (12 with normal penile function and four with erectile dysfunction). Subjects with normal erectile function showed gradual and centrifugal enhancement of the corpora cavernosa, while those with erectile dysfunction showed poor enhancement with abnormal progression. Sequential contrast-enhanced MR imaging provides additional morphologic information for the evaluation of erectile dysfunction.

The effect of paraquat inhalation on parkinsonism, organ morphology and anatomy of mice and its recovery with the application of etliringea hemisphaerica (blume, r.m. smith) crude extract

NASA Astrophysics Data System (ADS)

Muslim, Choirul; Nurul Kamila, Santi

2018-03-01

This research is aimed to understand the effect of paraquat herbicide inhalation on Parkinsonism, morphology and anatomy change in mice, and its recovery with Etliringea hemisphaerica crude extract application. Sixty mice were placed into three following groups: group R0 were mice receiving standard food ransom, R1 were a group of mice receiving the regular food ransom plus inhalation of 1% paraquat, and R2 were a group of R1 plus obtaining 0,39mg/bw extract E. hemisphaerica (Bl.) R.M. Smith). After 2 X 7 days of sub-sequential application of both paraquat and “helani tulip” extract, we observed the effects. The examination included bradikinesia attitude, postural instability and rigidity, morphology and anatomy of brain, liver, blood, lung, and kidney. The data were tabulated and analyzed qualitative and semi quantitative description on the behavioural disorder, the alteration of morphology and anatomy, and their remedy based on Sander 2004, Junqueira and Carneiro, 2007. The results showed that the application of paraquat caused strong bradikinesia, postural instability and rigidity. The treatment of the extract was only resulting in the bradikinesia removal but was minor improving the consequence of postural instability and rigidity. Paraquat was not affecting the morphology of neural brain but was altering the morphology and anatomy of lung, liver, blood, and the kidney. In general, the negative impact of the paraquat was weakly eliminated by the treatment of “helani tulip” extract.

Automatic sub-pixel coastline extraction based on spectral mixture analysis using EO-1 Hyperion data

NASA Astrophysics Data System (ADS)

Hong, Zhonghua; Li, Xuesu; Han, Yanling; Zhang, Yun; Wang, Jing; Zhou, Ruyan; Hu, Kening

2018-06-01

Many megacities (such as Shanghai) are located in coastal areas, therefore, coastline monitoring is critical for urban security and urban development sustainability. A shoreline is defined as the intersection between coastal land and a water surface and features seawater edge movements as tides rise and fall. Remote sensing techniques have increasingly been used for coastline extraction; however, traditional hard classification methods are performed only at the pixel-level and extracting subpixel accuracy using soft classification methods is both challenging and time consuming due to the complex features in coastal regions. This paper presents an automatic sub-pixel coastline extraction method (ASPCE) from high-spectral satellite imaging that performs coastline extraction based on spectral mixture analysis and, thus, achieves higher accuracy. The ASPCE method consists of three main components: 1) A Water- Vegetation-Impervious-Soil (W-V-I-S) model is first presented to detect mixed W-V-I-S pixels and determine the endmember spectra in coastal regions; 2) The linear spectral mixture unmixing technique based on Fully Constrained Least Squares (FCLS) is applied to the mixed W-V-I-S pixels to estimate seawater abundance; and 3) The spatial attraction model is used to extract the coastline. We tested this new method using EO-1 images from three coastal regions in China: the South China Sea, the East China Sea, and the Bohai Sea. The results showed that the method is accurate and robust. Root mean square error (RMSE) was utilized to evaluate the accuracy by calculating the distance differences between the extracted coastline and the digitized coastline. The classifier's performance was compared with that of the Multiple Endmember Spectral Mixture Analysis (MESMA), Mixture Tuned Matched Filtering (MTMF), Sequential Maximum Angle Convex Cone (SMACC), Constrained Energy Minimization (CEM), and one classical Normalized Difference Water Index (NDWI). The results from the three test sites indicated that the proposed ASPCE method extracted coastlines more efficiently than did the compared methods, and its coastline extraction accuracy corresponded closely to the digitized coastline, with 0.39 pixels, 0.40 pixels, and 0.35 pixels in the three test regions, showing that the ASPCE method achieves an accuracy below 12.0 m (0.40 pixels). Moreover, in the quantitative accuracy assessment for the three test sites, the ASPCE method shows the best performance in coastline extraction, achieving a 0.35 pixel-level at the Bohai Sea, China test site. Therefore, the proposed ASPCE method can extract coastline more accurately than can the hard classification methods or other spectral unmixing methods.

In-situ determination of metallic variation and multi-association in single particles by combining synchrotron microprobe, sequential chemical extraction and multivariate statistical analysis.

PubMed

Zhu, Yu-Min; Zhang, Hua; Fan, Shi-Suo; Wang, Si-Jia; Xia, Yi; Shao, Li-Ming; He, Pin-Jing

2014-07-15

Due to the heterogeneity of metal distribution, it is challenging to identify the speciation, source and fate of metals in solid samples at micro scales. To overcome these challenges single particles of air pollution control residues were detected in situ by synchrotron microprobe after each step of chemical extraction and analyzed by multivariate statistical analysis. Results showed that Pb, Cu and Zn co-existed as acid soluble fractions during chemical extraction, regardless of their individual distribution as chlorides or oxides in the raw particles. Besides the forms of Fe2O3, MnO2 and FeCr2O4, Fe, Mn, Cr and Ni were closely associated with each other, mainly as reducible fractions. In addition, the two groups of metals had interrelations with the Si-containing insoluble matrix. The binding could not be directly detected by micro-X-ray diffraction (μ-XRD) and XRD, suggesting their partial existence as amorphous forms or in the solid solution. The combined method on single particles can effectively determine metallic multi-associations and various extraction behaviors that could not be identified by XRD, μ-XRD or X-ray absorption spectroscopy. The results are useful for further source identification and migration tracing of heavy metals. Copyright © 2014 Elsevier B.V. All rights reserved.

Knowledge Representation of the Melody and Rhythm in Koto Songs

NASA Astrophysics Data System (ADS)

Deguchi, Sachiko; Shirai, Katsuhiko

This paper describes the knowledge representation of the melody and rhythm in koto songs based on the structure of the domain: the scale, melisma (the melody in a syllable), and bar. We have encoded koto scores and extracted 2,3,4-note melodic patterns sequentially from the voice part of koto scores. The 2,3,4-note patterns used in the melisma are limited and the percentages of top patterns are high. The 3,4-note melodic patterns are examined at each scale degree. These patterns are more restricted than the patterns that are possible under the constraint of the scale. These typical patterns on the scale represent the knowledge of koto players. We have analyzed rhythms in two different ways. We have extracted rhythms depending on each melodic pattern, while we have extracted rhythms depending on each bar. The former are complicated and the latter are typical. This result indicates that koto players recognize melodic patterns and rhythmic patterns independently. Our analyses show the melodic patterns and rhythmic patterns that are acquired by koto players. These patterns will be applied to the description of variations of the melisma to build a score database. These patterns will also be applied to a composition and education. The melodic patterns can be extracted from other genres of Japanese traditional music, foreign old folk songs or chants by using this method.

Critical evaluation of the ability of sequential extraction procedures to quantify discrete forms of selenium in sediments and soils.

PubMed

Wright, Michael T; Parker, David R; Amrhein, Christopher

2003-10-15

Sequential extraction procedures (SEPs) have been widely used to characterize the mobility, bioavailibility, and potential toxicity of trace elements in soils and sediments. Although oft-criticized, these methods may perform best with redox-labile elements (As, Hg, Se) for which more discrete biogeochemical phases may arise from variations in oxidation number. We critically evaluated two published SEPs for Se for their specificity and precision by applying them to four discrete components in an inert silica matrix: soluble Se(VI) (selenate), Se(IV) (selenite) adsorbed onto goethite, elemental Se, and a metal selenide (FeSe; achavalite). These were extracted both individually and in a mixed model sediment. The more selective of the two procedures was modified to further improve its selectivity (SEP 2M). Both SEP 1 and SEP 2M quantitatively recovered soluble selenate but yielded incomplete recoveries of adsorbed selenite (64% and 81%, respectively). SEP 1 utilizes 0.1 M K2S2O8 to target "organically associated" Se, but this extractant also solubilized most of the elemental (64%) and iron selenide (91%) components of the model sediment. In SEP 2M, the Na2SO3 used in step III is effective in extracting elemental Se but also extracted 17% of the Se from the iron selenide, such that the elemental fraction would be overestimated should both forms coexist. Application of SEP 2M to eight wetland sediments further suggested that the Na2SO3 in step III extracts some organically associated Se, so a NaOH extraction was inserted beforehand to yield a further modification, SEP 2OH. Results using this five-step procedure suggested that the four-step SEP 2M could overestimate elemental Se by as much as 43% due to solubilization of organic Se. Although still imperfect in its selectivity, SEP 20H may be the most suitable procedure for routine, accurate fractionation of Se in soils and sediments. However, the strong oxidant (NaOCl) used in the final step cannot distinguish between refractory organic forms of Se and pyritic Se that might form under sulfur-reducing conditions.

Leachability of Arsenic and Heavy Metals from Mine Tailings of Abandoned Metal Mines

PubMed Central

Lim, Mihee; Han, Gi-Chun; Ahn, Ji-Whan; You, Kwang-Suk; Kim, Hyung-Seok

2009-01-01

Mine tailings from an abandoned metal mine in Korea contained high concentrations of arsenic (As) and heavy metals [e.g., As: 67,336, Fe: 137,180, Cu: 764, Pb: 3,572, and Zn: 12,420 (mg/kg)]. US EPA method 6010 was an effective method for analyzing total arsenic and heavy metals concentrations. Arsenic in the mine tailings showed a high residual fraction of 89% by a sequential extraction. In Toxicity Characteristic Leaching Procedure (TCLP) and Korean Standard Leaching Test (KSLT), leaching concentrations of arsenic and heavy metals were very low [e.g., As (mg/L): 0.4 for TCLP and 0.2 for KSLT; cf. As criteria (mg/L): 5.0 for TCLP and 1.5 for KSLT]. PMID:20049231

Heterogeneous Suppression of Sequential Effects in Random Sequence Generation, but Not in Operant Learning.

PubMed

Shteingart, Hanan; Loewenstein, Yonatan

2016-01-01

There is a long history of experiments in which participants are instructed to generate a long sequence of binary random numbers. The scope of this line of research has shifted over the years from identifying the basic psychological principles and/or the heuristics that lead to deviations from randomness, to one of predicting future choices. In this paper, we used generalized linear regression and the framework of Reinforcement Learning in order to address both points. In particular, we used logistic regression analysis in order to characterize the temporal sequence of participants' choices. Surprisingly, a population analysis indicated that the contribution of the most recent trial has only a weak effect on behavior, compared to more preceding trials, a result that seems irreconcilable with standard sequential effects that decay monotonously with the delay. However, when considering each participant separately, we found that the magnitudes of the sequential effect are a monotonous decreasing function of the delay, yet these individual sequential effects are largely averaged out in a population analysis because of heterogeneity. The substantial behavioral heterogeneity in this task is further demonstrated quantitatively by considering the predictive power of the model. We show that a heterogeneous model of sequential dependencies captures the structure available in random sequence generation. Finally, we show that the results of the logistic regression analysis can be interpreted in the framework of reinforcement learning, allowing us to compare the sequential effects in the random sequence generation task to those in an operant learning task. We show that in contrast to the random sequence generation task, sequential effects in operant learning are far more homogenous across the population. These results suggest that in the random sequence generation task, different participants adopt different cognitive strategies to suppress sequential dependencies when generating the "random" sequences.

On-line hyphenation of solid-phase extraction to chromatographic separation of sulfonamides with fused-core columns in sequential injection chromatography.

PubMed

Batista, Alex D; Chocholouš, Petr; Satínský, Dalibor; Solich, Petr; Rocha, Fábio R P

2015-02-01

On-line sample pretreatment (clean-up and analyte preconcentration) is for the first time coupled to sequential injection chromatography. The approach combines anion-exchange solid-phase extraction and the highly effective pentafluorophenylpropyl (F5) fused-core particle column for separation of eight sulfonamide antibiotics with similar structures (sulfathiazole, sulfanilamide, sulfacetamide, sulfadiazine, sulfamerazine, sulfadimidine, sulfamethoxazole and sulfadimethoxine). The stationary phase was selected after a critical comparison of the performance achieved by three fused-core reversed phase columns (Ascentis(®) Express RP-Amide, Phenyl-Hexyl, and F5) and two monolithic columns (Chromolith(®) High Resolution RP-18 and CN). Acetonitrile and acetate buffer pH 5.0 at 0.60 mL min(-1) were used as mobile phase to perform the separations before spectrophotometric detection. The first mobile phase was successfully used as eluent from SPE column ensuring transfer of a narrow zone to the chromatographic column. Enrichment factors up to 39.2 were achieved with a 500 µL sample volume. The developed procedure showed analysis time <10.5 min, resolutions >1.83 with peak symmetry ≤1.52, LODs between 4.9 and 27 µg L(-1), linear response ranges from 30.0 to 1000.0 µg L(-1) (r(2)>0.996) and RSDs of peak heights <2.9% (n=6) at a 100 µg L(-1) level and enabled the screening control of freshwater samples contaminated at the 100 µg L(-1) level. The proposed approach expanded the analytical potentiality of SIC and avoided the time-consuming batch sample pretreatment step, thus minimizing risks of sample contamination and analyte losses. Copyright © 2014 Elsevier B.V. All rights reserved.

Transformation of zinc-concentrate in surface and subsurface environments: Implications for assessing zinc mobility/toxicity and choosing an optimal remediation strategy.

PubMed

Kwon, Man Jae; Boyanov, Maxim I; Yang, Jung-Seok; Lee, Seunghak; Hwang, Yun Ho; Lee, Ju Yeon; Mishra, Bhoopesh; Kemner, Kenneth M

2017-07-01

Zinc contamination in near- and sub-surface environments is a serious threat to many ecosystems and to public health. Sufficient understanding of Zn speciation and transport mechanisms is therefore critical to evaluating its risk to the environment and to developing remediation strategies. The geochemical and mineralogical characteristics of contaminated soils in the vicinity of a Zn ore transportation route were thoroughly investigated using a variety of analytical techniques (sequential extraction, XRF, XRD, SEM, and XAFS). Imported Zn-concentrate (ZnS) was deposited in a receiving facility and dispersed over time to the surrounding roadside areas and rice-paddy soils. Subsequent physical and chemical weathering resulted in dispersal into the subsurface. The species identified in the contaminated areas included Zn-sulfide, Zn-carbonate, other O-coordinated Zn-minerals, and Zn species bound to Fe/Mn oxides or clays, as confirmed by XAFS spectroscopy and sequential extraction. The observed transformation from S-coordinated Zn to O-coordinated Zn associated with minerals suggests that this contaminant can change into more soluble and labile forms as a result of weathering. For the purpose of developing a soil washing remediation process, the contaminated samples were extracted with dilute acids. The extraction efficiency increased with the increase of O-coordinated Zn relative to S-coordinated Zn in the sediment. This study demonstrates that improved understanding of Zn speciation in contaminated soils is essential for well-informed decision making regarding metal mobility and toxicity, as well as for choosing an appropriate remediation strategy using soil washing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sequential Actions of the AAA-ATPase Valosin-containing Protein (VCP)/p97 and the Proteasome 19 S Regulatory Particle in Sterol-accelerated, Endoplasmic Reticulum (ER)-associated Degradation of 3-Hydroxy-3-methylglutaryl-coenzyme A Reductase*

PubMed Central

Morris, Lindsey L.; Hartman, Isamu Z.; Jun, Dong-Jae; Seemann, Joachim; DeBose-Boyd, Russell A.

2014-01-01

Accelerated endoplasmic reticulum (ER)-associated degradation (ERAD) of the cholesterol biosynthetic enzyme 3-hydroxy-3-methylglutaryl-coenzyme A reductase results from its sterol-induced binding to ER membrane proteins called Insig-1 and Insig-2. This binding allows for subsequent ubiquitination of reductase by Insig-associated ubiquitin ligases. Once ubiquitinated, reductase becomes dislocated from ER membranes into the cytosol for degradation by 26 S proteasomes through poorly defined reactions mediated by the AAA-ATPase valosin-containing protein (VCP)/p97 and augmented by the nonsterol isoprenoid geranylgeraniol. Here, we report that the oxysterol 25-hydroxycholesterol and geranylgeraniol combine to trigger extraction of reductase across ER membranes prior to its cytosolic release. This conclusion was drawn from studies utilizing a novel assay that measures membrane extraction of reductase by determining susceptibility of a lumenal epitope in the enzyme to in vitro protease digestion. Susceptibility of the lumenal epitope to protease digestion and thus membrane extraction of reductase were tightly regulated by 25-hydroxycholesterol and geranylgeraniol. The reaction was inhibited by RNA interference-mediated knockdown of either Insigs or VCP/p97. In contrast, reductase continued to become membrane-extracted, but not cytosolically dislocated, in cells deficient for AAA-ATPases of the proteasome 19 S regulatory particle. These findings establish sequential roles for VCP/p97 and the 19 S regulatory particle in the sterol-accelerated ERAD of reductase that may be applicable to the ERAD of other substrates. PMID:24860107

Transformation of zinc-concentrate in surface and subsurface environments: Implications for assessing zinc mobility/toxicity and choosing an optimal remediation strategy

DOE PAGES

Kwon, Man Jae; Boyanov, Maxim I.; Yang, Jung -Seok; ...

2017-03-24

Zinc contamination in near- and sub-surface environments is a serious threat to many ecosystems and to public health. Sufficient understanding of Zn speciation and transport mechanisms is therefore critical to evaluating its risk to the environment and to developing remediation strategies. The geochemical and mineralogical characteristics of contaminated soils in the vicinity of a Zn ore transportation route were thoroughly investigated using a variety of analytical techniques (sequential extraction, XRF, XRD, SEM, and XAFS). Imported Zn-concentrate (ZnS) was deposited in a receiving facility and dispersed over time to the surrounding roadside areas and rice-paddy soils. Subsequent physical and chemical weatheringmore » resulted in dispersal into the subsurface. The species identified in the contaminated areas included Zn-sulfide, Zn-carbonate, other O-coordinated Zn-minerals, and Zn species bound to Fe/Mn oxides or clays, as confirmed by XAFS spectroscopy and sequential extraction. The observed transformation from S-coordinated Zn to O-coordinated Zn associated with minerals suggests that this contaminant can change into more soluble and labile forms as a result of weathering. For the purpose of developing a soil washing remediation process, the contaminated samples were extracted with dilute acids. The extraction efficiency increased with the increase of O-coordinated Zn relative to S-coordinated Zn in the sediment. Furthermore, this study demonstrates that improved understanding of Zn speciation in contaminated soils is essential for well-informed decision making regarding metal mobility and toxicity, as well as for choosing an appropriate remediation strategy using soil washing.« less

Arsenic mobility in soils impacted by tailings at Zimapán, México

NASA Astrophysics Data System (ADS)

Aurora Armienta, M.; Resendiz, Isabel; Múgica, Violeta; Cruz, Olivia; Aguayo, Alejandra; Ceniceros, Nora

2014-05-01

The Zimapán mining zone, in Central México is one of the worldwide sites known for As contamination. For more than 20 years and until recently, As-rich groundwater, mainly due to mineralization in a limestone aquifer, was an important source of As exposure to the inhabitants. In addition, decades of ore processing have produced hazardous wastes (tailings), many of them settled in the town outskirts. Although mineralogical and chemical differences exist among the various deposits; every one has high As contents (up to several thousands mg/kg) and other toxic elements that may be released to the nearby soils. To assess As mobility in soils impacted by tailings, total and sequential fractionation determinations were performed in 120 superficial and 40 cm depth samples collected at various distances near three of the impoundments. Higher total As concentrations were measured in the dry (up to 51,534 mg/kg) with respect to the rainy season (up to 23,570 mg/kg) indicating the occurrence of As wash off by rain. Although concentrations were lower in the deep regarding the superficial samples at most sites, As contents reached several thousands mg/kg at 40 cm depth indicating also its vertical transport that may reach the shallow aquifer. Sequential extractions showed differences between soils impacted by highly oxidized (red) tailings and low oxidized (gray) deposits. Most of the As occurs in the Fe-Mn oxides fraction (up to 92%) followed by the organic matter and sulfides fraction (up to 52 %) in soils close to red tailings, while organic matter and sulfide fraction contain most of the As (up to 95%) in soil samples close to low-oxidized deposits. Arsenic proportion in the residual fraction increased with distance from oxidized tailings. Low pH values (from 2.0 to 2.5) in superficial soils revealed the influence of acid mine drainage at distances up to 40 m from the red deposit. In contrast, the lowest pH was 7.1 in soils impacted by low-oxidized deposits, reflecting the limestone environment. Arsenic airborne transport was evidenced by the presence of a total As concentration of 30,780 mg/kg in soils collected at 120 m in front of the tailings crossing a ravine. Although sequential extraction showed that most of the As is present in relatively low-mobility fractions, total As concentrations indicate that tailings impoundments constitute another source of environmental As exposure.

Multifunctional picoliter droplet manipulation platform and its application in single cell analysis.

PubMed

Gu, Shu-Qing; Zhang, Yun-Xia; Zhu, Ying; Du, Wen-Bin; Yao, Bo; Fang, Qun

2011-10-01

We developed an automated and multifunctional microfluidic platform based on DropLab to perform flexible generation and complex manipulations of picoliter-scale droplets. Multiple manipulations including precise droplet generation, sequential reagent merging, and multistep solid-phase extraction for picoliter-scale droplets could be achieved in the present platform. The system precision in generating picoliter-scale droplets was significantly improved by minimizing the thermo-induced fluctuation of flow rate. A novel droplet fusion technique based on the difference of droplet interfacial tensions was developed without the need of special microchannel networks or external devices. It enabled sequential addition of reagents to droplets on demand for multistep reactions. We also developed an effective picoliter-scale droplet splitting technique with magnetic actuation. The difficulty in phase separation of magnetic beads from picoliter-scale droplets due to the high interfacial tension was overcome using ferromagnetic particles to carry the magnetic beads to pass through the phase interface. With this technique, multistep solid-phase extraction was achieved among picoliter-scale droplets. The present platform had the ability to perform complex multistep manipulations to picoliter-scale droplets, which is particularly required for single cell analysis. Its utility and potentials in single cell analysis were preliminarily demonstrated in achieving high-efficiency single-cell encapsulation, enzyme activity assay at the single cell level, and especially, single cell DNA purification based on solid-phase extraction.

Algae as an electron donor promoting sulfate reduction for the bioremediation of acid rock drainage.

PubMed

Ayala-Parra, Pedro; Sierra-Alvarez, Reyes; Field, Jim A

2016-11-05

This study assessed bioremediation of acid rock drainage in simulated permeable reactive barriers (PRB) using algae, Chlorella sorokiniana, as the sole electron donor for sulfate-reducing bacteria. Lipid extracted algae (LEA), the residues of biodiesel production, were compared with whole cell algae (WCA) as an electron donor to promote sulfate-reducing activity. Inoculated columns containing anaerobic granular sludge were fed a synthetic medium containing H2SO4 and Cu(2+). Sulfate, sulfide, Cu(2+) and pH were monitored throughout the experiment of 123d. Cu recovered in the column packing at the end of the experiment was evaluated using sequential extraction. Both WCA and LEA promoted 80% of sulfate removal (12.7mg SO4(2-) d(-1)) enabling near complete Cu removal (>99.5%) and alkalinity generation raising the effluent pH to 6.5. No noteworthy sulfate reduction, alkalinity formation and Cu(2+) removal were observed in the endogenous control. In algae amended-columns, Cu(2+) was precipitated with biogenic H2S produced by sulfate reduction. Formation of CuS was evidenced by sequential extraction and X-ray diffraction. LEA and WCA provided similar levels of electron donor based on the COD balance. The results demonstrate an innovative passive remediation system using residual algae biomass from the biodiesel industry. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of first pass bolus AIFs extracted from sequential 18F-FDG PET and DSC-MRI of mice

NASA Astrophysics Data System (ADS)

Evans, Eleanor; Sawiak, Stephen J.; Ward, Alexander O.; Buonincontri, Guido; Hawkes, Robert C.; Adrian Carpenter, T.

2014-01-01

Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time-activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration-time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and 18F-FDG respectively to ascertain the technique‧s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies.

Comparison of first pass bolus AIFs extracted from sequential 18F-FDG PET and DSC-MRI of mice.

PubMed

Evans, Eleanor; Sawiak, Stephen J; Ward, Alexander O; Buonincontri, Guido; Hawkes, Robert C; Carpenter, T Adrian

2014-01-11

Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time-activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration-time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and 18 F-FDG respectively to ascertain the technique's validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies.

Sequential solvent extraction for the modes of occurrence of selenium in coals of different ranks from the Huaibei Coalfield, China

USGS Publications Warehouse

Zhang, Y.; Liu, Gaisheng; Chou, C.-L.; Wang, L.; Kang, Y.

2007-01-01

Forms of selenium in bituminous coal, anthracite, and cokeite (natural coke) from Huaibei Coalfield, Anhui, China, have been determined by sequential solvent extraction. The selenium content in bulk samples is 4.0, 2.4, and 2.0 ??g/g in bituminous coal, anthracite, and cokeite, respectively. The six forms of selenium determined by six-step solvent extraction are water-leachable, ion-exchangeable, organic matter-associated, carbonate-associated, silicate-associated, and sulfide-associated. The predominant forms of selenium in bituminous coal are organic matter-associated (39.0%), sulfide-associated (21.1%), and silicate bound (31.8%); these three forms account for 92% of the total. The organic matter bound-selenium decrease dramatically from bituminous coal (39.0%) to anthracite (11.6%) and to cokeite (0%), indicating that organic matter bound selenium is converted to other forms during metamorphism of the coal, most likely sulfide-form. The sulfide-associated form increased remarkably from bituminous coal (21.1%) to anthracite (50.4%) and cokeite (54.5%), indicating the formation of selenium sulfide, possibly in pyrite during the transformation of bituminous coal to anthracite and cokeite. The silicate-associated selenium in bituminous coal (31.8%) is much higher than that in anthracite (16.4%) and cokeite (15.8%), indicating that silicate-associated selenium is partly converted to sulfide during metamorphism. ?? 2007 Zhang et al; licensee BioMed Central Ltd.

Cranberry versus placebo in the prevention of urinary infections in multiple sclerosis: a multicenter, randomized, placebo-controlled, double-blind trial.

PubMed

Gallien, Philippe; Amarenco, Gérard; Benoit, Nicolas; Bonniaud, Véronique; Donzé, Cécile; Kerdraon, Jacques; de Seze, Marianne; Denys, Pierre; Renault, Alain; Naudet, Florian; Reymann, Jean Michel

2014-08-01

Our aim was to assess the usefulness of cranberry extract in multiple sclerosis (MS) patients suffering from urinary disorders. In total, 171 adult MS outpatients with urinary disorders presenting at eight centers were randomized (stratification according to center and use of clean intermittent self-catheterization) to cranberry versus placebo in a 1-year, prospective, double-blind study that was analyzed using a sequential method on an intent-to-treat basis. An independent monitoring board analyzed the results of the analyses each time 40 patients were assessed on the main endpoint. Cranberry extract (36 mg proanthocyanidins per day) or a matching placebo was taken by participants twice daily for 1 year. The primary endpoint was the time to first symptomatic urinary tract infection (UTI), subject to validation by a validation committee. The second sequential analyses allowed us to accept the null hypothesis (no difference between cranberry and placebo). There was no difference in time to first symptomatic UTI distribution across 1 year, with an estimated hazard ratio of 0.99, 95% CI [0.61, 1.60] (p = 0.97). Secondary endpoints and tolerance did not differ between groups. Taking cranberry extract versus placebo twice a day did not prevent UTI occurrence in MS patients with urinary disorders. Trial Registration NCT00280592. © The Author(s) 2014.

The role of chemometrics in single and sequential extraction assays: a review. Part II. Cluster analysis, multiple linear regression, mixture resolution, experimental design and other techniques.

PubMed

Giacomino, Agnese; Abollino, Ornella; Malandrino, Mery; Mentasti, Edoardo

2011-03-04

Single and sequential extraction procedures are used for studying element mobility and availability in solid matrices, like soils, sediments, sludge, and airborne particulate matter. In the first part of this review we reported an overview on these procedures and described the applications of chemometric uni- and bivariate techniques and of multivariate pattern recognition techniques based on variable reduction to the experimental results obtained. The second part of the review deals with the use of chemometrics not only for the visualization and interpretation of data, but also for the investigation of the effects of experimental conditions on the response, the optimization of their values and the calculation of element fractionation. We will describe the principles of the multivariate chemometric techniques considered, the aims for which they were applied and the key findings obtained. The following topics will be critically addressed: pattern recognition by cluster analysis (CA), linear discriminant analysis (LDA) and other less common techniques; modelling by multiple linear regression (MLR); investigation of spatial distribution of variables by geostatistics; calculation of fractionation patterns by a mixture resolution method (Chemometric Identification of Substrates and Element Distributions, CISED); optimization and characterization of extraction procedures by experimental design; other multivariate techniques less commonly applied. Copyright © 2010 Elsevier B.V. All rights reserved.

Structural characterization of alkali-soluble polysaccharides from Panax ginseng C. A. Meyer

PubMed Central

Ji, Li; Jie, Zhenjing; Ying, Xin; Yue, Qi; Zhou, Yifa

2018-01-01

Panax ginseng C. A. Meyer (ginseng) has been widely used as a herb and functional food in the world. Polysaccharides are the main active components of ginseng. In this paper, the polysaccharides were sequentially extracted by 50 mM Na2CO3, 1 M KOH and 4 M KOH from ginseng roots treated sequentially with hot water, α-amylase and ethylenediaminetetraacetic acid extraction. Na2CO3-soluble ginseng polysaccharide (NGP) was fractionated into one neutral and three acidic fractions by anion exchange and gel permeation chromatography. Fourier transform infrared, NMR and methylation analysis indicated acidic fractions in NGP were highly branched rhamnogalacturonan-I domains, with  → 4)-α-GalpA-(1 → 2)-α-Rhap-(1 → disaccharide repeating units as backbone and β-1,4-galactan, α-1,5/1,3,5-arabinan and type II arabinogalactan as side chains. 1-KGP (1 M KOH-soluble ginseng polysaccharide) and 4-KGP (4 M KOH-soluble ginseng polysaccharide) were mainly composed of hemicellulose besides starch-like polysaccharides and minor pectin. Antibody detection, enzymic hydrolysis, high performance anion exchange chromatography and methylation analysis demonstrated xylan was the major component in 1-KGP, while xyloglucan was predominant in 4-KGP. Comparing the polysaccharides obtained by different solvent extractions, we have a comprehensive understanding about total ginseng polysaccharides. PMID:29657770

Direct comparison of XAFS spectroscopy and sequential extraction for arsenic speciation in coal

USGS Publications Warehouse

Huggins, Frank E.; Huffman, G.P.; Kolker, A.; Mroczkowski, S.; Palmer, C.A.; Finkelman, R.B.

2000-01-01

The speciation of arsenic in an Ohio bituminous coal and a North Dakota lignite has been examined by the complementary methods of arsenic XAFS spectroscopy and sequential extraction by aqueous solutions of ammonium acetate, HCl, HF, and HNO3. In order to facilitate a more direct comparison of the two methods, the arsenic XAFS spectra were obtained from aliquots of the coal prepared after each stage of the leaching procedure. For the aliquots, approximately linear correlations (r2 > 0.98 for the Ohio coal, > 0.90 for the ND lignite) were observed between the height of the edge-step in the XAFS analysis and the concentration of arsenic measured by instrumental neutron activation analysis. Results from the leaching sequence indicate that there are two major arsenic forms present in both coals; one is removed by leaching with HCl and the other by HNO3. Whereas the XAFS spectral signatures of the arsenic leached by HCl are compatible with arsenate for both coals, the arsenic leached by HNO3 is identified as arsenic associated with pyrite for the Ohio coal and as an As3+ species for the North Dakota lignite. Minor arsenate forms persist in both coals after the final leaching with nitric acid. The arsenate forms extracted in HCl are believed to be oxidation products derived from the other major arsenic forms upon exposure of the pulverized coals to air.

Comparison of supercritical fluid and Soxhlet extractions for the quantification of hydrocarbons from Euphorbia macroclada.

PubMed

Ozcan, Adnan; Ozcan, Asiye Safa

2004-10-08

This study compares conventional Soxhlet extraction and analytical scale supercritical fluid extraction (SFE) for their yields in extracting of hydrocarbons from arid-land plant Euphorbia macroclada. The plant material was firstly sequentially extracted with supercritical carbon dioxide, modified with 10% methanol (v/v) in the optimum conditions that is a pressure of 400atm and a temperature of 50 degrees C and then it was sonicated in methylene chloride for an additional 4h. E. macroclada was secondly extracted by using a Soxhlet apparatus at 30 degrees C for 8h in methylene chloride. The validated SFE was then compared to the extraction yield of E. macroclada with a Soxhlet extraction by using the Student's t-test at the 95% confidence level. All of extracts were fractionated with silica-gel in a glass column to get better hydrocarbon yields. Thus, the highest hydrocarbons yield from E. macroclada was achieved with SFE (5.8%) when it compared with Soxhlet extractions (1.1%). Gas chromatography (GC) analysis was performed to determine the quantitative hydrocarbons from plant material. The greatest quantitative hydrocarbon recovery from GC was obtained by supercritical carbon dioxide extract (0.6mgg(-1)).

General unknown screening, antioxidant and anti-inflammatory potential of Dendrobium macrostachyum Lindl.

PubMed

Sukumaran, Nimisha Pulikkal; Yadav, R Hiranmai

2016-01-01

D. macrostachyum is an epiphytic orchid abundant in Southern India and is reported for pain relief in folklore. The objective of the present study was to determine in vitro free radical scavenging and anti-inflammatory activity of D. macrostachyum and to perform LCMS based metabolic profiling of the plant. Sequential stem and leaf extracts were assessed for its antioxidant and anti-inflammatory activity by in vitro methods. The antioxidant activity determined by assays based on the decolourization of the radical monocation of DPPH, ABTS and reducing power. Total amount of phenolics for quantitative analysis of antioxidative components was estimated. In vitro anti-inflammatory activity was evaluated using protein denaturation assay, membrane stabilization assay and proteinase inhibitory activity. Methanolic extract of plant was subjected to LCMS. The stem ethanolic extracts exhibited significant IC50 value of 10.21, 31.54 and 142.97 μg/ml respectively for DPPH, ABTS radical scavenging and reducing power activity. The ethanol and water extract was highly effective as albumin denaturation inhibitors (IC50 = 114.13 and 135.818 μg/ml respectively) and proteinase inhibitors (IC50 = 72.49 and 129.681 μg/ml respectively). Membrane stabilization was also noticeably inhibited by the stem ethanolic extract among other extracts (IC50 = 89.33 μg/ml) but comparatively lower to aspirin standard (IC50 = 83.926 μg/ml). The highest total phenol content was exhibited by ethanolic stem and leaf extracts respectively at 20 and 16 mg of gallic acid equivalents of dry extract. On LCMS analysis 20 constituents were identified and it included chemotaxonomic marker for Dendrobium species. The results showed a relatively high concentration of phenolics, high scavenger activity and high anti-inflammatory activity of the stem extract compared to the leaf extract. The results indicate that the plant can be a potential source of bioactive compounds.

General unknown screening, antioxidant and anti-inflammatory potential of Dendrobium macrostachyum Lindl.

PubMed Central

Sukumaran, Nimisha Pulikkal; Yadav, R. Hiranmai

2016-01-01

Context: D. macrostachyum is an epiphytic orchid abundant in Southern India and is reported for pain relief in folklore. Aims: The objective of the present study was to determine in vitro free radical scavenging and anti-inflammatory activity of D. macrostachyum and to perform LCMS based metabolic profiling of the plant. Settings and Design: Sequential stem and leaf extracts were assessed for its antioxidant and anti-inflammatory activity by in vitro methods. Materials and Methods: The antioxidant activity determined by assays based on the decolourization of the radical monocation of DPPH, ABTS and reducing power. Total amount of phenolics for quantitative analysis of antioxidative components was estimated. In vitro anti-inflammatory activity was evaluated using protein denaturation assay, membrane stabilization assay and proteinase inhibitory activity. Methanolic extract of plant was subjected to LCMS. Results: The stem ethanolic extracts exhibited significant IC50 value of 10.21, 31.54 and 142.97 μg/ml respectively for DPPH, ABTS radical scavenging and reducing power activity. The ethanol and water extract was highly effective as albumin denaturation inhibitors (IC50 = 114.13 and 135.818 μg/ml respectively) and proteinase inhibitors (IC50 = 72.49 and 129.681 μg/ml respectively). Membrane stabilization was also noticeably inhibited by the stem ethanolic extract among other extracts (IC50 = 89.33 μg/ml) but comparatively lower to aspirin standard (IC50 = 83.926 μg/ml). The highest total phenol content was exhibited by ethanolic stem and leaf extracts respectively at 20 and 16 mg of gallic acid equivalents of dry extract. On LCMS analysis 20 constituents were identified and it included chemotaxonomic marker for Dendrobium species. Conclusions: The results showed a relatively high concentration of phenolics, high scavenger activity and high anti-inflammatory activity of the stem extract compared to the leaf extract. The results indicate that the plant can be a potential source of bioactive compounds. PMID:27621524

THE PARADOX OF SIGN LANGUAGE MORPHOLOGY

PubMed Central

Aronoff, Mark; Meir, Irit; Sandler, Wendy

2011-01-01

Sign languages have two strikingly different kinds of morphological structure: sequential and simultaneous. The simultaneous morphology of two unrelated sign languages, American and Israeli Sign Language, is very similar and is largely inflectional, while what little sequential morphology we have found differs significantly and is derivational. We show that at least two pervasive types of inflectional morphology, verb agreement and classifier constructions, are iconically grounded in spatiotemporal cognition, while the sequential patterns can be traced to normal historical development. We attribute the paucity of sequential morphology in sign languages to their youth. This research both brings sign languages much closer to spoken languages in their morphological structure and shows how the medium of communication contributes to the structure of languages.* PMID:22223926

Cross-correlation patterns in social opinion formation with sequential data

NASA Astrophysics Data System (ADS)

Chakrabarti, Anindya S.

2016-11-01

Recent research on large-scale internet data suggests existence of patterns in the collective behavior of billions of people even though each of them may pursue own activities. In this paper, we interpret online rating activity as a process of forming social opinion about individual items, where people sequentially choose a rating based on the current information set comprising all previous ratings and own preferences. We construct an opinion index from the sequence of ratings and we show that (1) movie-specific opinion converges much slower than an independent and identically distributed (i.i.d.) sequence of ratings, (2) rating sequence for individual movies shows lesser variation compared to an i.i.d. sequence of ratings, (3) the probability density function of the asymptotic opinions has more spread than that defined over opinion arising from i.i.d. sequence of ratings, (4) opinion sequences across movies are correlated with significantly higher and lower correlation compared to opinion constructed from i.i.d. sequence of ratings, creating a bimodal cross-correlation structure. By decomposing the temporal correlation structures from panel data of movie ratings, we show that the social effects are very prominent whereas group effects cannot be differentiated from those of surrogate data and individual effects are quite small. The former explains a large part of extreme positive or negative correlations between sequences of opinions. In general, this method can be applied to any rating data to extract social or group-specific effects in correlation structures. We conclude that in this particular case, social effects are important in opinion formation process.

Extractability and Bioavailability of Pb and As in Historically Contaminated Orchard Soil: Effects of Compost Amendments

PubMed Central

Fleming, Margaret; Yiping, Tai; Ping, Zhuang; McBride, Murray B.

2015-01-01

The availability of Pb and As in an historically contaminated orchard soil, after amendment with compost and aging in the field, was determined by single-step chemical extraction with 1.0 M ammonium acetate at pH 4.8, sequential extraction using the modified BCR test, and a redworm bioassay in the laboratory. The efficiency of soil Pb extraction by ammonium acetate was greater at higher total soil Pb but was reduced by compost amendment. Conversely, the extraction efficiency of total soil As increased with compost amendment, but was not sensitive to total soil As. The redworm bioassay indicated Pb (but not As) bioavailability to be reduced by soil amendment with compost, a result consistent with the ammonium acetate extraction test but not reflected in modified BCR test. Electron microprobe studies of the orchard soil revealed Pb and As to be spatially associated in discrete particles along with phosphorus and iron. PMID:23474982

Chemical studies on the polysaccharides of Salicornia brachiata.

PubMed

Sanandiya, Naresh D; Siddhanta, A K

2014-11-04

A group of 12 polysaccharide extracts were prepared from the tips, stem and roots of an Indian halophyte Salicornia brachiata Roxb. obtained by sequential extractions with cold water (CW), hot water (HW), aqueous ammonium oxalate (OX) and aqueous sodium hydroxide (ALK) solutions. Monosaccharide composition analysis revealed that all the polysaccharide extract samples consisted primarily of rhamnose, arabinose, mannose, galactose, glucose, whereas ribose and xylose were present only in some of the extracts. All the extracts exhibited low apparent viscosity (1.47-2.02 cP) and sulphate and contained no prominent toxic metal ions. Fucose was detected only in OX extract of the roots. These polysaccharides were found to be heterogeneous and highly branched (glycoside linkage analysis, size-exclusion chromatography, (13)C-NMR, FT-IR, circular dichroism and optical rotation data). Physico-chemical analyses of these polysaccharides including uronic acid, sulphate and protein contents were also carried out. This constitutes the first report on the profiling of Salicornia polysaccharides. Copyright © 2014 Elsevier Ltd. All rights reserved.

Occurrence and abundance of carbohydrates and amino compounds in sequentially extracted labile soil organic matter fractions.

USDA-ARS?s Scientific Manuscript database

This study aimed to investigate the content of carbohydrates and amino compounds in three labile fraction of soil organic matter (SOM). Soil samples were collected from two agricultural fields in southern Italy and the light fraction (LF), the 500–53-µm particulate organic matter (POM) and the mobil...

Allergenicity of Peanut Proteins is Retained Following Enzymatic Hydrolysis

USDA-ARS?s Scientific Manuscript database

Rationale: Hydrolysis of peanut proteins by food-grade enzymes may reduce allergenicity and could lead to safer forms of immunotherapy. Methods: Light roasted peanut flour extracts were digested with pepsin (37°C, pH 2), Alcalase (60°C pH 8), or Flavourzyme (50°C, pH 7) up to 1 hr, or sequentially w...

A Bayesian sequential design using alpha spending function to control type I error.

PubMed

Zhu, Han; Yu, Qingzhao

2017-10-01

We propose in this article a Bayesian sequential design using alpha spending functions to control the overall type I error in phase III clinical trials. We provide algorithms to calculate critical values, power, and sample sizes for the proposed design. Sensitivity analysis is implemented to check the effects from different prior distributions, and conservative priors are recommended. We compare the power and actual sample sizes of the proposed Bayesian sequential design with different alpha spending functions through simulations. We also compare the power of the proposed method with frequentist sequential design using the same alpha spending function. Simulations show that, at the same sample size, the proposed method provides larger power than the corresponding frequentist sequential design. It also has larger power than traditional Bayesian sequential design which sets equal critical values for all interim analyses. When compared with other alpha spending functions, O'Brien-Fleming alpha spending function has the largest power and is the most conservative in terms that at the same sample size, the null hypothesis is the least likely to be rejected at early stage of clinical trials. And finally, we show that adding a step of stop for futility in the Bayesian sequential design can reduce the overall type I error and reduce the actual sample sizes.

Method for contour extraction for object representation

DOEpatents

Skourikhine, Alexei N.; Prasad, Lakshman

2005-08-30

Contours are extracted for representing a pixelated object in a background pixel field. An object pixel is located that is the start of a new contour for the object and identifying that pixel as the first pixel of the new contour. A first contour point is then located on the mid-point of a transition edge of the first pixel. A tracing direction from the first contour point is determined for tracing the new contour. Contour points on mid-points of pixel transition edges are sequentially located along the tracing direction until the first contour point is again encountered to complete tracing the new contour. The new contour is then added to a list of extracted contours that represent the object. The contour extraction process associates regions and contours by labeling all the contours belonging to the same object with the same label.

[Effects of Fulvic Acid on Absorption and Form Distribution of Heavy Metals on Sediments].

PubMed

Li, Yu-qing; He, Jiang; Lü, Chang-wei; Fan, Ming-de; Wang, Wei; Zhang, Rui-qing; Xie, Zhi- lei; Wang, Jing-hua; Yu, Bo; En, He; Ding, Tao

2016-03-15

Based on the extracted fulvic acid (FA) from Lake Wuliangsuhai sediments by sequential alkali extraction, this work studied the effects of FA on the adsorption and fraction distribution of heavy metals (HM) on sediments using original sediments and sediments treated with 30% H₂O₂ as adsorbents. The results showed both organic matter and FA had effects on the HM adsorption onto sediments; The treatments of FA-free conditions and the sediments treated by H₂O₂ showed relatively strong influence on Cu²⁺ adsorption, which decreased the Cu²⁺ adsorption by 17.85%. With the increasing FA addition, the adsorption percentage of HM on both types of sediments showed gradually decreasing trends, with the order of Cu²⁺ > Cd²⁺ > Zn²⁺ > Pb²⁺; when the FA content was more than 5% , FA became the governing factor on the decreasing adsorption percentage of HM. With increasing FA addition, forms distribution of HM showed significant changes in both types of sediments; i. e. FA additions showed significant negative and positive correlations with percentages of metals bound to carbonates and organic matter, respectively, since the FA addition increased the H⁺ concentration of the system, in which H⁺ could activate the metals bound to carbonate from the sediments. As an organophilic weak element, the fraction percentage of Cd bound to organic matter was the lowest with the minimal changes.

Prophylactic mesh to prevent parastomal hernia after end colostomy: a meta-analysis and trial sequential analysis.

PubMed

López-Cano, M; Brandsma, H-T; Bury, K; Hansson, B; Kyle-Leinhase, I; Alamino, J G; Muysoms, F

2017-04-01

Prevention of parastomal hernia (PSH) formation is crucial, given the high prevalence and difficulties in the surgical repair of PSH. To investigate the effect of a preventive mesh in PSH formation after an end colostomy, we aimed to meta-analyze all relevant randomized controlled trials (RCTs). We searched five databases. For each trial, we extracted risk ratios (RRs) of the effects of mesh or no mesh. The primary outcome was incidence of PSH with a minimum follow-up of 12 months with a clinical and/or computed tomography diagnosis. RRs were combined using the random-effect model (Mantel-Haenszel). To control the risk of type I error, we performed a trial sequential analysis (TSA). Seven RCTs with low risk of bias (451 patients) were included. Meta-analysis for primary outcome showed a significant reduction of the incidence of PSH using a mesh (RR 0.43, 95% CI 0.26-0.71; P = 0.0009). Regarding TSA calculation for the primary outcome, the accrued information size (451) was 187.1% of the estimated required information size (RIS) (241). Wound infection showed no statistical differences between groups (RR 0.77, 95% CI 0.39-1.54; P = 0.46). PSH repair rate showed a significant reduction in the mesh group (RR 0.28 (95% CI 0.10-0.78; P = 0.01). PSH prevention with mesh when creating an end colostomy reduces the incidence of PSH, the risk for subsequent PSH repair and does not increase wound infections. TSA shows that the RIS is reached for the primary outcome. Additional RCTs in the previous context are not needed.

The impact of wine components on fractionation of Cu and Fe in model wine systems: Macromolecules, phenolic and sulfur compounds.

PubMed

Kontoudakis, Nikolaos; Smith, Mark; Guo, Anque; Smith, Paul A; Scollary, Geoffrey R; Wilkes, Eric N; Clark, Andrew C

2017-08-01

A variety of techniques have been developed with the ability to measure different forms of metals in wine with the ultimate aim of providing a more accurate indicator of metal induced spoilage of wine. This study was conducted in order to identify which wine components influence the measurement of Cu and Fe in their fractionated and/or electrochemically active forms. The measurement techniques involved detection of labile Cu by stripping potentiometry and fractionation of Cu and Fe by sequential solid phase extraction, with detection by inductively coupled plasma-optical emission spectroscopy. The wine components assessed included those extracted from wine (red wine tannin, white wine protein, white wine polysaccharide, red wine polyphenol, white wine polyphenol), and commercially available monomeric compounds, including phenolic compounds and sulfur-containing compounds. For Cu, only hydrogen sulfide, which is known to induce the formation of Cu(I) sulfide, showed any appreciable influence on the fractionation and electrochemical detection of Cu. This form of Cu was also identified as the major component of red and white wines. For Fe, the fractionation was different for red versus white wine, and influenced significantly by extracted red wine polyphenol, (-)-epicatechin, gallic acid and tartaric acid. The wine components showed more influence on Fe at pH4.00 compared to pH3.25. These results enable a targeted use of these techniques in the assessment of metal-induced spoilage of wine. Copyright © 2016 Elsevier Ltd. All rights reserved.

A hybrid monolithic column based on boronate-functionalized graphene oxide nanosheets for online specific enrichment of glycoproteins.

PubMed

Zhou, Chanyuan; Chen, Xiaoman; Du, Zhuo; Li, Gongke; Xiao, Xiaohua; Cai, Zongwei

2017-05-19

A hybrid monolithic column based on aminophenylboronic acid (APBA)-functionalized graphene oxide (GO) has been developed and used for selective enrichment of glycoproteins. The APBA/GO composites were homogeneously incorporated into a polymer monolithic column with the help of oligomer matrix and followed by in situ polymerization. The effect of dispersion of APBA/GO composites in the polymerization mixture on the performance of the monolithic column was explored in detail. The presence of graphene oxide not only enlarged the BET surface area from 6.3m 2 /g to 169.4m 2 /g, but also provided abundant boronic acid moieties for glycoprotein extraction, which improved the enrichment selectivity and efficiency for glycoproteins. The APBA/GO hybrid monolithic column was incorporated into a sequential injection system, which facilitated online extraction of proteins. Combining the superior properties of extraordinary surface area of GO and the affinity interaction of APBA to glycoproteins, the APBA/GO hybrid monolithic column showed higher enrichment factors for glycoproteins than other proteins without cis-diol-containing groups. Also, under comparable or even shorter processing time and without the addition of any organic solvent, it showed higher binding capacity toward glycoproteins compared with the conventional boronate affinity monolithic column. The practical applicability of this system was demonstrated by processing of egg white samples for extraction of ovalbumin and ovotransferrin, and satisfactory results were obtained by assay with SDS-PAGE. Copyright © 2017 Elsevier B.V. All rights reserved.

Lineup Composition, Suspect Position, and the Sequential Lineup Advantage

ERIC Educational Resources Information Center

Carlson, Curt A.; Gronlund, Scott D.; Clark, Steven E.

2008-01-01

N. M. Steblay, J. Dysart, S. Fulero, and R. C. L. Lindsay (2001) argued that sequential lineups reduce the likelihood of mistaken eyewitness identification. Experiment 1 replicated the design of R. C. L. Lindsay and G. L. Wells (1985), the first study to show the sequential lineup advantage. However, the innocent suspect was chosen at a lower rate…

Learning to Monitor Machine Health with Convolutional Bi-Directional LSTM Networks

PubMed Central

Zhao, Rui; Yan, Ruqiang; Wang, Jinjiang; Mao, Kezhi

2017-01-01

In modern manufacturing systems and industries, more and more research efforts have been made in developing effective machine health monitoring systems. Among various machine health monitoring approaches, data-driven methods are gaining in popularity due to the development of advanced sensing and data analytic techniques. However, considering the noise, varying length and irregular sampling behind sensory data, this kind of sequential data cannot be fed into classification and regression models directly. Therefore, previous work focuses on feature extraction/fusion methods requiring expensive human labor and high quality expert knowledge. With the development of deep learning methods in the last few years, which redefine representation learning from raw data, a deep neural network structure named Convolutional Bi-directional Long Short-Term Memory networks (CBLSTM) has been designed here to address raw sensory data. CBLSTM firstly uses CNN to extract local features that are robust and informative from the sequential input. Then, bi-directional LSTM is introduced to encode temporal information. Long Short-Term Memory networks (LSTMs) are able to capture long-term dependencies and model sequential data, and the bi-directional structure enables the capture of past and future contexts. Stacked, fully-connected layers and the linear regression layer are built on top of bi-directional LSTMs to predict the target value. Here, a real-life tool wear test is introduced, and our proposed CBLSTM is able to predict the actual tool wear based on raw sensory data. The experimental results have shown that our model is able to outperform several state-of-the-art baseline methods. PMID:28146106

Learning to Monitor Machine Health with Convolutional Bi-Directional LSTM Networks.

PubMed

Zhao, Rui; Yan, Ruqiang; Wang, Jinjiang; Mao, Kezhi

2017-01-30

In modern manufacturing systems and industries, more and more research efforts have been made in developing effective machine health monitoring systems. Among various machine health monitoring approaches, data-driven methods are gaining in popularity due to the development of advanced sensing and data analytic techniques. However, considering the noise, varying length and irregular sampling behind sensory data, this kind of sequential data cannot be fed into classification and regression models directly. Therefore, previous work focuses on feature extraction/fusion methods requiring expensive human labor and high quality expert knowledge. With the development of deep learning methods in the last few years, which redefine representation learning from raw data, a deep neural network structure named Convolutional Bi-directional Long Short-Term Memory networks (CBLSTM) has been designed here to address raw sensory data. CBLSTM firstly uses CNN to extract local features that are robust and informative from the sequential input. Then, bi-directional LSTM is introduced to encode temporal information. Long Short-Term Memory networks(LSTMs) are able to capture long-term dependencies and model sequential data, and the bi-directional structure enables the capture of past and future contexts. Stacked, fully-connected layers and the linear regression layer are built on top of bi-directional LSTMs to predict the target value. Here, a real-life tool wear test is introduced, and our proposed CBLSTM is able to predict the actual tool wear based on raw sensory data. The experimental results have shown that our model is able to outperform several state-of-the-art baseline methods.

Delay test generation for synchronous sequential circuits

NASA Astrophysics Data System (ADS)

Devadas, Srinivas

1989-05-01

We address the problem of generating tests for delay faults in non-scan synchronous sequential circuits. Delay test generation for sequential circuits is a considerably more difficult problem than delay testing of combinational circuits and has received much less attention. In this paper, we present a method for generating test sequences to detect delay faults in sequential circuits using the stuck-at fault sequential test generator STALLION. The method is complete in that it will generate a delay test sequence for a targeted fault given sufficient CPU time, if such a sequence exists. We term faults for which no delay test sequence exists, under out test methodology, sequentially delay redundant. We describe means of eliminating sequential delay redundancies in logic circuits. We present a partial-scan methodology for enhancing the testability of difficult-to-test of untestable sequential circuits, wherein a small number of flip-flops are selected and made controllable/observable. The selection process guarantees the elimination of all sequential delay redundancies. We show that an intimate relationship exists between state assignment and delay testability of a sequential machine. We describe a state assignment algorithm for the synthesis of sequential machines with maximal delay fault testability. Preliminary experimental results using the test generation, partial-scan and synthesis algorithm are presented.

Flotation as a remediation technique for heavily polluted dredged material. 2. Characterisation of flotated fractions.

PubMed

Cauwenberg, P; Verdonckt, F; Maes, A

1998-01-19

The particle size distribution and the metal speciation of the heavy metals were investigated on dredged sediment and on the fractions obtained by mechanical agitated (Denver) flotation. The transition metal ions (cadmium, copper, lead and zinc) were flotated specifically independent of the particle size. Particle size analysis, EDTA extraction and sequential extracts indicated that during flotation a redistribution of metals occurred due to the oxidation of metal sulphides. This oxidation process was more pronounced when the flotation was performed at higher pH values and resulted in a decrease in flotation specificity.

Proposal of a sequential treatment methodology for the safe reuse of oil sludge-contaminated soil.

PubMed

Mater, L; Sperb, R M; Madureira, L A S; Rosin, A P; Correa, A X R; Radetski, C M

2006-08-25

In this study sequential steps were used to treat and immobilize oil constituents of an oil sludge-contaminated soil. Initially, the contaminated soil was oxidized by a Fenton type reaction (13 wt% for H(2)O(2); 10mM for Fe(2+)). The oxidative treatment period of 80 h was carried out under three different pH conditions: 20 h at pH 6.5, 20 h at pH 4.5, and 40 h at pH 3.0. The oxidized contaminated sample (3 kg) was stabilized and solidified for 2h with clay (1 kg) and lime (2 kg). Finally, this mixture was solidified by sand (2 kg) and Portland cement (4 kg). In order to evaluate the efficiency of different processes to treat and immobilize oil contaminants of the oil sludge-contaminated soil, leachability and solubility tests were performed and extracts were analyzed according to the current Brazilian waste regulations. Results showed that the Fenton oxidative process was partially efficient in degrading the oil contaminants in the soil, since residual concentrations were found for the PAH and BTEX compounds. Leachability tests showed that clay-lime stabilization/solidification followed by Portland cement stabilization/solidification was efficient in immobilizing the recalcitrant and hazardous constituents of the contaminated soil. These two steps stabilization/solidification processes are necessary to enhance environmental protection (minimal leachability) and to render final product economically profitable. The treated waste is safe enough to be used on environmental applications, like roadbeds blocks.

Bacterial diversity in the active stage of a bioremediation system for mineral oil hydrocarbon-contaminated soils.

PubMed

Popp, Nicole; Schlömann, Michael; Mau, Margit

2006-11-01

Soils contaminated with mineral oil hydrocarbons are often cleaned in off-site bioremediation systems. In order to find out which bacteria are active during the degradation phase in such systems, the diversity of the active microflora in a degrading soil remediation system was investigated by small-subunit (SSU) rRNA analysis. Two sequential RNA extracts from one soil sample were generated by a procedure incorporating bead beating. Both extracts were analysed separately by generating individual SSU rDNA clone libraries from cDNA of the two extracts. The sequencing results showed moderate diversity. The two clone libraries were dominated by Gammaproteobacteria, especially Pseudomonas spp. Alphaproteobacteria and Betaproteobacteria were two other large groups in the clone libraries. Actinobacteria, Firmicutes, Bacteroidetes and Epsilonproteobacteria were detected in lower numbers. The obtained sequences were predominantly related to genera for which cultivated representatives have been described, but were often clustered together in the phylogenetic tree, and the sequences that were most similar were originally obtained from soils and not from pure cultures. Most of the dominant genera in the clone libraries, e.g. Pseudomonas, Acinetobacter, Sphingomonas, Acidovorax and Thiobacillus, had already been detected in (mineral oil hydrocarbon) contaminated environmental samples. The occurrence of the genera Zymomonas and Rhodoferax was novel in mineral oil hydrocarbon-contaminated soil.

Efficacy of Plectranthus glandulosus (Lamiaceae) and Callistemon rigidus (Myrtaceae) Leaf Extract Fractions to Callosobruchus maculatus (Coleoptera: Bruchidae).

PubMed

Danga, Simon Pierre Yinyang; Nukenine, Elias Nchiwan; Younoussa, Lame; Adler, Cornel; Esimone, Charles Okechukwu

2015-01-01

As part of on-going efforts to use eco-friendly alternatives to chemical pesticides, methanol crude extracts of Plectranthus glandulosus and Callistemon rigidus leaves were sequentially fractionated in hexane, chloroform, ethyl acetate, and methanol to establish the most active fraction(s) against Callosobruchus maculatus in cowpea. Cowpea seeds (25 g) were treated with 0.5, 1, 2, and 4 g/kg of extract to evaluate the contact toxicity and F1 progeny production of the beetles in the laboratory. Mortality was recorded 1, 3, and 7 d postexposure. P. glandulosus hexane fraction was more toxic than the other fractions recording 100% mortality at 4 g/kg, within 7 d with LC50 of 0.39 g/kg. Hexane fraction of C. rigidus showed superior toxicity, causing 100% mortality at 4 g/kg within only 1 d of exposure with LC50 of 1.02 g/kg. All the fractions greatly reduced progeny emergence, with C. rigidus hexane fraction being the best progeny inhibitor. Fractions of P. glandulosus and C. rigidus leaves had sufficient efficacy to be a component of storage pest management package for C. maculatus. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

MaPLE: A MapReduce Pipeline for Lattice-based Evaluation and Its Application to SNOMED CT

PubMed Central

Zhang, Guo-Qiang; Zhu, Wei; Sun, Mengmeng; Tao, Shiqiang; Bodenreider, Olivier; Cui, Licong

2015-01-01

Non-lattice fragments are often indicative of structural anomalies in ontological systems and, as such, represent possible areas of focus for subsequent quality assurance work. However, extracting the non-lattice fragments in large ontological systems is computationally expensive if not prohibitive, using a traditional sequential approach. In this paper we present a general MapReduce pipeline, called MaPLE (MapReduce Pipeline for Lattice-based Evaluation), for extracting non-lattice fragments in large partially ordered sets and demonstrate its applicability in ontology quality assurance. Using MaPLE in a 30-node Hadoop local cloud, we systematically extracted non-lattice fragments in 8 SNOMED CT versions from 2009 to 2014 (each containing over 300k concepts), with an average total computing time of less than 3 hours per version. With dramatically reduced time, MaPLE makes it feasible not only to perform exhaustive structural analysis of large ontological hierarchies, but also to systematically track structural changes between versions. Our change analysis showed that the average change rates on the non-lattice pairs are up to 38.6 times higher than the change rates of the background structure (concept nodes). This demonstrates that fragments around non-lattice pairs exhibit significantly higher rates of change in the process of ontological evolution. PMID:25705725

Compaction Kinetics on Single DNAs: Purified Nucleosome Reconstitution Systems versus Crude Extract

PubMed Central

Wagner, Gaudeline; Bancaud, Aurélien; Quivy, Jean-Pierre; Clapier, Cédric; Almouzni, Geneviève; Viovy, Jean-Louis

2005-01-01

Kinetics of compaction on single DNA molecules are studied by fluorescence videomicroscopy in the presence of 1), Xenopus egg extracts and 2), purified nucleosome reconstitution systems using a combination of histones with either the histone chaperone Nucleosome Assembly Protein (NAP-1) or negatively charged macromolecules such as polyglutamic acid and RNA. The comparison shows that the compaction rates can differ by a factor of up to 1000 for the same amount of histones, depending on the system used and on the presence of histone tails, which can be subjected to post-translational modifications. Reactions with purified reconstitution systems follow a slow and sequential mechanism, compatible with the deposition of one (H3-H4)2 tetramer followed by two (H2A-H2B) dimers. Addition of the histone chaperone NAP-1 increases both the rate of the reaction and the packing ratio of the final product. These stimulatory effects cannot be obtained with polyglutamic acid or RNA, suggesting that yNAP-1 impact on the reaction cannot simply be explained in terms of charge screening. Faster compaction kinetics and higher packing ratios are reproducibly reached with extracts, indicating a role of additional components present in this system. Data are discussed and models proposed to account for the kinetics obtained in our single-molecule assay. PMID:16100259

MaPLE: A MapReduce Pipeline for Lattice-based Evaluation and Its Application to SNOMED CT.

PubMed

Zhang, Guo-Qiang; Zhu, Wei; Sun, Mengmeng; Tao, Shiqiang; Bodenreider, Olivier; Cui, Licong

2014-10-01

Non-lattice fragments are often indicative of structural anomalies in ontological systems and, as such, represent possible areas of focus for subsequent quality assurance work. However, extracting the non-lattice fragments in large ontological systems is computationally expensive if not prohibitive, using a traditional sequential approach. In this paper we present a general MapReduce pipeline, called MaPLE (MapReduce Pipeline for Lattice-based Evaluation), for extracting non-lattice fragments in large partially ordered sets and demonstrate its applicability in ontology quality assurance. Using MaPLE in a 30-node Hadoop local cloud, we systematically extracted non-lattice fragments in 8 SNOMED CT versions from 2009 to 2014 (each containing over 300k concepts), with an average total computing time of less than 3 hours per version. With dramatically reduced time, MaPLE makes it feasible not only to perform exhaustive structural analysis of large ontological hierarchies, but also to systematically track structural changes between versions. Our change analysis showed that the average change rates on the non-lattice pairs are up to 38.6 times higher than the change rates of the background structure (concept nodes). This demonstrates that fragments around non-lattice pairs exhibit significantly higher rates of change in the process of ontological evolution.

Assessment of the influence of traffic-related particles in urban dust using sequential selective extraction and oral bioaccessibility tests.

PubMed

Patinha, C; Durães, N; Sousa, P; Dias, A C; Reis, A P; Noack, Y; Ferreira da Silva, E

2015-08-01

Urban dust is a heterogeneous mix, where traffic-related particles can combine with soil mineral compounds, forming a unique and site-specific material. These traffic-related particles are usually enriched in potentially harmful elements, enhancing the health risk for population by inhalation or ingestion. Urban dust samples from Estarreja city and traffic-related particles (brake dust and white traffic paint) were studied to understand the relative contribution of the traffic particles in the geochemical behaviour of urban dust and to evaluate the long-term impacts of the metals on an urban environment, as well as the risk to the populations. It was possible to distinguish two groups of urban dust samples according to Cu behaviour: (1) one group with low amounts of fine particles (<38 µm), low contents of organic material, high percentage of Cu in soluble phases, and low Cu bioaccessible fraction (Bf) values. This group showed similar chemical behaviour with the brake dust samples of low- to mid-range car brands (with more than 10 years old), composed by coarser wear particles; and (2) another group with greater amounts of fine particles (<38 µm), with low percentage of Cu associated with soluble phases, and with greater Cu Bf values. This group behaved similar to those found for brake dust of mid- to high-range car brands (with less than 10 years old). The results obtained showed that there is no direct correlation between the geoavailability of metals estimated by sequential selective chemical extraction (SSCE) and the in vitro oral bioaccessibility (UBM) test. Thus, oral bioaccessibility of urban dust is site specific. Geoavailability was greatly dependent on particle size, where the bioaccessibility tended to increase with a reduction in particle diameter. As anthropogenic particles showed high metal concentration and a smaller size than mineral particles, urban dusts are of major concern to the populations' health, since fine particles are easily re-suspended, easily ingested, and show high metal bioaccessibility. In addition, Estarreja is a coastal city often influenced by winds, which favours the re-suspension of small-sized contaminated particles. Even if the risk to the population does not represent an acute case, it should not be overlooked, and this study can serve as baseline study for cities under high traffic influence.

Immobilization and phytotoxicity of chromium in contaminated soil remediated by CMC-stabilized nZVI.

PubMed

Wang, Yu; Fang, Zhanqiang; Kang, Yuan; Tsang, Eric Pokeung

2014-06-30

The toxic effect of Cr(VI)-contaminated soil remediated by sodium carboxymethyl cellulose stabilized nanoscale zero-valent iron (CMC-stabilized nZVI) was assessed through in vitro toxicity and phytotoxicity tests. In vitro tests showed that 0.09 g L(-1) of Fe(0) nanoparticles (soil-to-solution ratio was 1 g:5 mL) significantly reduced the toxicity characteristic leaching procedure (TCLP) leachability and physiological based extraction test (PBET) bioaccessibility of Cr by 82% and 58%, respectively. Sequential extraction procedures (SEP) revealed that exchangeable (EX) Cr was completely converted to Fe-Mn oxides (OX) and organic matter (OM). Accordingly, phytotoxicity tests indicated that after 72-h remediation, Cr uptakes by edible rape and Chinese cabbage were suppressed by 61% and 36%, respectively. Moreover, no significant increase in Cr uptake was observed for either species after a 1-month static period for the amended soil. Regarding Fe absorption, germination and seedling growth, both plant species were significantly affected by CMC-nZVI-exposed soils. However, similar phytotoxicity tests conducted after 1 month showed an improvement in cultivation for both plants. Overall, this study demonstrated that CMC-nZVI could significantly enhance Cr immobilization, which reduced its leachability, bioavailability and bioaccumulation by plants. From a detoxification perspective, such remediation is technologically feasible and shows great potential in field applications. Copyright © 2014 Elsevier B.V. All rights reserved.

Arsenic bioaccessibility and speciation in the soils amended with organoarsenicals and drinking-water treatment residuals based on a long-term greenhouse study

NASA Astrophysics Data System (ADS)

Nagar, Rachana; Sarkar, Dibyendu; Makris, Konstantinos C.; Datta, Rupali

2014-10-01

SummaryAlthough organoarsenical pesticides are no longer applied to agricultural fields in the US, their widespread use until recently, toxicity, and potential transformation to inorganic arsenic has raised serious concern. Drinking-water treatment residuals (WTRs) have been proposed as a low-cost amendment for remediation of organoarsenical pesticide contaminated soils. A long-term greenhouse study was initiated to evaluate the effect WTR application on bioaccessibility, geochemical partitioning, and speciation of the Dimethylarsinic acid (DMA). Two soils (Immokalee and Orelia series) were spiked with DMA (1500 mg As kg-1) and amended with an Al- and Fe-based WTR at two rates (5% and 10% by wt.). Soil sampling was done immediately after spiking (time zero) and after 0.25, 0.5, 1, and 3 (time final) years of equilibration and subjected to bioaccessibility test and sequential extraction. Results showed that compared to the unamended (no WTR) control, As bioaccessibility in the WTR-amended soils significantly (p < 0.001) decreased by 40-70% in 3 years. The Fe-WTR was more effective than Al-WTR in decreasing soil As bioaccessibility. The in vitro and water-extracted samples were subjected to As speciation at time zero and time final. Results showed transformation of DMA into inorganic As, irrespective of WTR amendments. The Orelia soil showed significantly (p < 0.001) higher transformation than the Immokalee soil.

Protein-transitions in and out of the dough matrix in wheat flour mixing.

PubMed

Wang, Xiaolong; Appels, Rudi; Zhang, Xiaoke; Bekes, Ferenc; Torok, Kitti; Tomoskozi, Sandor; Diepeveen, Dean; Ma, Wujun; Islam, Shahidul

2017-02-15

Sequential protein behavior in the wheat dough matrix under continuous mixing and heating treatment has been studied using Mixolab-dough samples from two Australian wheat cultivars, Westonia and Wyalkatchem. Size exclusion high performance liquid chromatography (SE-HPLC) and two-dimensional gel electrophoresis (2-DGE) analysis indicated that 32min (80°C) was a critical time point in forming large protein complexes and loosing extractability of several protein groups like y-type high molecular weight glutenin subunits (HMW-GSs), gamma-gliadins, beta-amylases, serpins, and metabolic proteins with higher mass. Up to 32min (80°C) Westonia showed higher protein extractability compared to Wyalkatchem although it was in the opposite direction thereafter. Twenty differentially expressed proteins could be assigned to chromosomes 1D, 3A, 4A, 4B, 4D, 6A, 6B, 7A and 7B. The results expanded the range of proteins associated with changes in the gluten-complex during processing and provided targets for selecting new genetic variants associated with altered quality attributes of the flour. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of remediation process with plant-derived biosurfactant for recovery of heavy metals from contaminated soils.

PubMed

Hong, Kyung-Jin; Tokunaga, Shuzo; Kajiuchi, Toshio

2002-10-01

A washing process was studied to evaluate the efficiency of saponin on remediating heavy metal contaminated soils. Three different types of soils (Andosol: soil A, Cambisol: soil B, Regosol: soil C) were washed with saponin in batch experiments. Utilization of saponin was effective for removal of heavy metals from soils, attaining 90-100% of Cd and 85-98% of Zn extractions. The fractionations of heavy metals removed by saponin were identified using the sequential extraction. Saponin was effective in removing the exchangeable and carbonated fractions of heavy metals from soils. In recovery procedures, the pH of soil leachates was increased to about 10.7, leading to separate heavy metals as hydroxide precipitates and saponin solute. In addition recycle of used saponin is considered to be effective for the subsequent utilization. The limits of Japanese leaching test were met for all of the soil residues after saponin treatment. As a whole, this study shows that saponin can be used as a cleaning agent for remediation of heavy metal contaminated soils.

Extraction and identification of α-amylase inhibitor peptides from Nephelium lappacheum and Nephelium mutabile seed protein using gastro-digestive enzymes.

PubMed

Evaristus, Natashya Anak; Wan Abdullah, Wan Nadiah; Gan, Chee-Yuen

2018-04-01

The potential of N. lappacheum and N. mutabile seed as a source of α-amylase inhibitor peptides was explored based on the local traditional practice of using the seed. Different gastro-digestive enzymes (i.e. pepsin or chymotrypsin) or a sequential digestion were used to extract the peptides. The effects of digestion time and enzyme to substrate (E:S) ratio on the α-amylase inhibitory activity were investigated. Results showed that chymotrypsin was effective in producing the inhibitor peptides from rambutan seed protein at E:S ratio 1:20 for 1 h, whereas pepsin was more effective for pulasan seed protein under the same condition. A total of 20 and 31 novel inhibitor peptides were identified, respectively. These peptides could bind with the subsites of α-amylase (i.e. Trp58, Trp59, Tyr62, Asp96, Arg195, Asp197, Glu233, His299, Asp300, and His305) and formed a sliding barrier that preventing the formation of enzyme/substrate intermediate leading to lower α-amylase activity. Copyright © 2018 Elsevier Inc. All rights reserved.

Two endogenous proteins that induce cell wall extension in plants

NASA Technical Reports Server (NTRS)

McQueen-Mason, S.; Durachko, D. M.; Cosgrove, D. J.

1992-01-01

Plant cell enlargement is regulated by wall relaxation and yielding, which is thought to be catalyzed by elusive "wall-loosening" enzymes. By employing a reconstitution approach, we found that a crude protein extract from the cell walls of growing cucumber seedlings possessed the ability to induce the extension of isolated cell walls. This activity was restricted to the growing region of the stem and could induce the extension of isolated cell walls from various dicot stems and the leaves of amaryllidaceous monocots, but was less effective on grass coleoptile walls. Endogenous and reconstituted wall extension activities showed similar sensitivities to pH, metal ions, thiol reducing agents, proteases, and boiling in methanol or water. Sequential HPLC fractionation of the active wall extract revealed two proteins with molecular masses of 29 and 30 kD associated with the activity. Each protein, by itself, could induce wall extension without detectable hydrolytic breakdown of the wall. These proteins appear to mediate "acid growth" responses of isolated walls and may catalyze plant cell wall extension by a novel biochemical mechanism.

METAL FRACTIONATION IN SOILS AND ASSESSMENT OF ENVIROMENTAL CONTAMINATION IN THE VALLECAMONICA, ITALY

PubMed Central

Borgese, L.; Federici, S.; Zacco, A.; Gianoncelli, A.; Rizzo, L.; Smith, D. R.; Donna, F.; Lucchini, R.; Depero, L. E.; Bontempi, E.

2013-01-01

Metal contamination was investigated in soils of the Vallecamonica, an area in the northern part of the Brescia province (Italy) where ferroalloy industries were active for a century until 2001. The extent in which emissions from ferroalloy plants affected metal concentration in soils is not known in this area. In this study the geogenic and/or anthropogenic origin of metals in soils were estimated. A modified Community Bureau of Reference sequential chemical extraction method followed by inductive coupled plasma optical emission spectroscopy analyses were employed to evaluate the potential bioavailability of Al, Cd, Mn, Fe, Cr, Zn, and Pb in soils. Principal components analysis was used to assess the relationships among metal sources in soil samples from different locations. This approach allowed to distinguish different loadings and mobilities of metals in soils collected in different areas. Results showed high concentrations and readily extractability of Mn in the Vallecamonica soils, which may suggest potential bioavailability for organisms and may create an environmental risk and potential health risk of human exposure. PMID:23338992

Characterization of trace metal removal products in vertical flow bioreactor substrates at the Mayer Ranch Passive Treatment System in the Tar Creek Superfund Site.

PubMed

LaBar, Julie A; Nairn, Robert W

2018-05-01

A passive treatment system (PTS), including two parallel vertical flow bioreactors (VFBR), was constructed in 2008 for the treatment of unabated net-alkaline ferruginous mine drainage in the Tar Creek Superfund Site in northeastern Oklahoma. Water quality data collected since the PTS began operation indicate significant removal of trace metals in the VFBR. Results of a sequential extraction procedure (SEP) performed on substrate samples showed that the majority of Cd, Co, Fe, Ni, Pb, and Zn were retained in the refractory organic/sulfide fraction. Subsequent acid volatile sulfide/simultaneously extracted metals (AVS/SEM) analyses confirmed the retention of Cd, Fe, Pb, and Zn as sulfides, but Co and Ni results were less certain. The majority of trace metals were retained as insoluble products in the VFBR, while up to 20% of most of the trace metals were retained in soluble, bioavailable fractions. Nearly 70% of Mn was retained in the soluble and bioavailable exchangeable, carbonate, and labile organic fractions. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Variation in soil Mn fractions as affected by long-term manure amendment using atomic absorption spectrophotometer in a typical grassland of inner Mongolia].

PubMed

Fu, Ming-ming; Jiang, Yong; Bai, Yong-fei; Zhang, Yu-ge; Xu, Zhu-wen; Li, Bo

2012-08-01

The effect of sheep manure amendment on soil manganese fractions was conducted in a 11 year experiment at inner Mongolia grassland, using sequential extraction procedure in modified Community Bureau of Reference, and determined by atomic absorption spectrophotometer. Five treatments with dry sheep manure addition rate 0, 50, 250, 750, and 1500 g x m(-2) x yr(-1), respectively, were carried out in this experiment. Results showed that the recovery rate for total Mn was 91.4%-105.9%, as the percentage recovered from the summation of the improved BCR results with aqua regia extractable contents, and it was 97.2%-102.9% from certified soil reference materials. Plant available exchangeable Mn could be enhanced by 47.89%, but reducible and total Mn contents decreased significantly under heavy application of manure at depth of 0-5 cm. The effect of manure amendment on Mn fractions was greater in 0-5 cm than in 5-10 cm soil layer. The results are benefit to micronutrient fractions determination and nutrient management in grassland soils.

Bilingualism modulates the white matter structure of language-related pathways.

PubMed

Hämäläinen, Sini; Sairanen, Viljami; Leminen, Alina; Lehtonen, Minna

2017-05-15

Learning and speaking a second language (L2) may result in profound changes in the human brain. Here, we investigated local structural differences along two language-related white matter trajectories, the arcuate fasciculus and the inferior fronto-occipital fasciculus (IFOF), between early simultaneous bilinguals and late sequential bilinguals. We also examined whether early exposure to two languages might lead to a more bilateral structural organization of the arcuate fasciculus. Fractional anisotropy, mean and radial diffusivities (FA, MD, and RD respectively) were extracted to analyse tract-specific changes. Additionally, global voxel-wise effects were investigated with Tract-Based Spatial Statistics (TBSS). We found that relative to late exposure, early exposure to L2 leads to increased FA along a phonology-related segment of the arcuate fasciculus, but induces no modulations along the IFOF, associated to semantic processing. Late sequential bilingualism, however, was associated with decreased MD along the bilateral IFOF. Our results suggest that early vs. late bilingualism may lead to qualitatively different kind of changes in the structural language-related network. Furthermore, we show that early bilingualism contributes to the structural laterality of the arcuate fasciculus, leading to a more bilateral organization of these perisylvian language-related tracts. Copyright © 2017 Elsevier Inc. All rights reserved.

Deconvolution of complex differential scanning calorimetry profiles for protein transitions under kinetic control.

PubMed

Toledo-Núñez, Citlali; Vera-Robles, L Iraís; Arroyo-Maya, Izlia J; Hernández-Arana, Andrés

2016-09-15

A frequent outcome in differential scanning calorimetry (DSC) experiments carried out with large proteins is the irreversibility of the observed endothermic effects. In these cases, DSC profiles are analyzed according to methods developed for temperature-induced denaturation transitions occurring under kinetic control. In the one-step irreversible model (native → denatured) the characteristics of the observed single-peaked endotherm depend on the denaturation enthalpy and the temperature dependence of the reaction rate constant, k. Several procedures have been devised to obtain the parameters that determine the variation of k with temperature. Here, we have elaborated on one of these procedures in order to analyze more complex DSC profiles. Synthetic data for a heat capacity curve were generated according to a model with two sequential reactions; the temperature dependence of each of the two rate constants involved was determined, according to the Eyring's equation, by two fixed parameters. It was then shown that our deconvolution procedure, by making use of heat capacity data alone, permits to extract the parameter values that were initially used. Finally, experimental DSC traces showing two and three maxima were analyzed and reproduced with relative success according to two- and four-step sequential models. Copyright © 2016 Elsevier Inc. All rights reserved.

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

Bae, Wookeun; Shin, Eung Bai; Lee, Kil Chul

The potential hazard of landfill wastes was previously evaluated by examining the extraction procedures for individual waste, although various wastes were co-disposed of in actual landfills. This paper investigates the reduction of extraction-procedure toxicity by co-disposing various combinations of two wastes. When two wastes are mixed homogeneously, the extraction of heavy metals from the waste mixture is critically affected by the extract pH. Thus, co-disposal wastes will have a resultant pH between the pH values of its constituent. The lower the resultant pH, the lower the concentrations of heavy metals in the extract. When these wastes are extracted sequentially, themore » latter extracted waste has a stronger influence on the final concentration of heavy metals in the extract. Small-scale lysimeter experiments confirm that when heavy-metal-bearing leachates Generated from hazardous-waste lysimeters are passed through a nonhazardous-waste lysimeter filled with compost, briquette ash, or refuse-incineration ashes, the heavy-metal concentration in the final leachates decreases significantly. Thus, the heavy-metal leaching could be attenuated if a less extraction-procedure-toxic waste were placed at the bottom of a landfill. 3 refs., 4 figs., 5 tabs.« less

Use of inorganic and organic wastes for in situ immobilisation of Pb and Zn in a contaminated alkaline soil.

PubMed

Zhou, Y-F; Haynes, R J; Naidu, R

2012-05-01

This study aims to examine whether addition of immobilising agents to a sandy, alkaline (pH = 8.1) soil, which had been contaminated with Pb and Zn by airborne particles from a Pb/Zn smelter, would substantially reduce metal bioavailability. The effectiveness of five waste materials (blast furnace (BF) slag, alum water treatment (WT) sludge, red mud, sugar mill mud and green waste compost) as metal immobilising agents was evaluated by incubating them with a contaminated soil for a period of 12 months at rates of 5% and 10% (w/w), after which, Rhodes grass was grown in the soils in a greenhouse study. Additions of WT sludge, BF slag and red mud reduced CaCl(2), CH(3)COOH, HCl and EDTA-extractable Zn but compost and mill mud had no appreciable immobilising effects. Additions of all amendments reduced levels of CaCl(2), CH(3)COOH and HCl-extractable Pb although concentrations of EDTA-extractable Pb remained unchanged. A sequential extraction procedure showed that additions of mill mud and compost increased the percentage of total Pb and Zn present in the oxidisable fraction whilst additions of the other materials increased the percentage present in the residual fraction. Rhodes grass yields were promoted greatly by additions of red mud, compost and particularly mill mud, and yields were negatively correlated with tissue Pb concentrations and extractable Pb. Red mud was the most effective material for lowering extractable Pb and Zn levels simultaneously while mill mud and compost were notably effective for Pb. A field evaluation in the study area is justified.

Sequential Modular Position and Momentum Measurements of a Trapped Ion Mechanical Oscillator

NASA Astrophysics Data System (ADS)

Flühmann, C.; Negnevitsky, V.; Marinelli, M.; Home, J. P.

2018-04-01

The noncommutativity of position and momentum observables is a hallmark feature of quantum physics. However, this incompatibility does not extend to observables that are periodic in these base variables. Such modular-variable observables have been suggested as tools for fault-tolerant quantum computing and enhanced quantum sensing. Here, we implement sequential measurements of modular variables in the oscillatory motion of a single trapped ion, using state-dependent displacements and a heralded nondestructive readout. We investigate the commutative nature of modular variable observables by demonstrating no-signaling in time between successive measurements, using a variety of input states. Employing a different periodicity, we observe signaling in time. This also requires wave-packet overlap, resulting in quantum interference that we enhance using squeezed input states. The sequential measurements allow us to extract two-time correlators for modular variables, which we use to violate a Leggett-Garg inequality. Signaling in time and Leggett-Garg inequalities serve as efficient quantum witnesses, which we probe here with a mechanical oscillator, a system that has a natural crossover from the quantum to the classical regime.

Vaccine adverse event text mining system for extracting features from vaccine safety reports.

PubMed

Botsis, Taxiarchis; Buttolph, Thomas; Nguyen, Michael D; Winiecki, Scott; Woo, Emily Jane; Ball, Robert

2012-01-01

To develop and evaluate a text mining system for extracting key clinical features from vaccine adverse event reporting system (VAERS) narratives to aid in the automated review of adverse event reports. Based upon clinical significance to VAERS reviewing physicians, we defined the primary (diagnosis and cause of death) and secondary features (eg, symptoms) for extraction. We built a novel vaccine adverse event text mining (VaeTM) system based on a semantic text mining strategy. The performance of VaeTM was evaluated using a total of 300 VAERS reports in three sequential evaluations of 100 reports each. Moreover, we evaluated the VaeTM contribution to case classification; an information retrieval-based approach was used for the identification of anaphylaxis cases in a set of reports and was compared with two other methods: a dedicated text classifier and an online tool. The performance metrics of VaeTM were text mining metrics: recall, precision and F-measure. We also conducted a qualitative difference analysis and calculated sensitivity and specificity for classification of anaphylaxis cases based on the above three approaches. VaeTM performed best in extracting diagnosis, second level diagnosis, drug, vaccine, and lot number features (lenient F-measure in the third evaluation: 0.897, 0.817, 0.858, 0.874, and 0.914, respectively). In terms of case classification, high sensitivity was achieved (83.1%); this was equal and better compared to the text classifier (83.1%) and the online tool (40.7%), respectively. Our VaeTM implementation of a semantic text mining strategy shows promise in providing accurate and efficient extraction of key features from VAERS narratives.

Dependency-based long short term memory network for drug-drug interaction extraction.

PubMed

Wang, Wei; Yang, Xi; Yang, Canqun; Guo, Xiaowei; Zhang, Xiang; Wu, Chengkun

2017-12-28

Drug-drug interaction extraction (DDI) needs assistance from automated methods to address the explosively increasing biomedical texts. In recent years, deep neural network based models have been developed to address such needs and they have made significant progress in relation identification. We propose a dependency-based deep neural network model for DDI extraction. By introducing the dependency-based technique to a bi-directional long short term memory network (Bi-LSTM), we build three channels, namely, Linear channel, DFS channel and BFS channel. All of these channels are constructed with three network layers, including embedding layer, LSTM layer and max pooling layer from bottom up. In the embedding layer, we extract two types of features, one is distance-based feature and another is dependency-based feature. In the LSTM layer, a Bi-LSTM is instituted in each channel to better capture relation information. Then max pooling is used to get optimal features from the entire encoding sequential data. At last, we concatenate the outputs of all channels and then link it to the softmax layer for relation identification. To the best of our knowledge, our model achieves new state-of-the-art performance with the F-score of 72.0% on the DDIExtraction 2013 corpus. Moreover, our approach obtains much higher Recall value compared to the existing methods. The dependency-based Bi-LSTM model can learn effective relation information with less feature engineering in the task of DDI extraction. Besides, the experimental results show that our model excels at balancing the Precision and Recall values.

Identification of DNA-Binding Proteins Using Mixed Feature Representation Methods.

PubMed

Qu, Kaiyang; Han, Ke; Wu, Song; Wang, Guohua; Wei, Leyi

2017-09-22

DNA-binding proteins play vital roles in cellular processes, such as DNA packaging, replication, transcription, regulation, and other DNA-associated activities. The current main prediction method is based on machine learning, and its accuracy mainly depends on the features extraction method. Therefore, using an efficient feature representation method is important to enhance the classification accuracy. However, existing feature representation methods cannot efficiently distinguish DNA-binding proteins from non-DNA-binding proteins. In this paper, a multi-feature representation method, which combines three feature representation methods, namely, K-Skip-N-Grams, Information theory, and Sequential and structural features (SSF), is used to represent the protein sequences and improve feature representation ability. In addition, the classifier is a support vector machine. The mixed-feature representation method is evaluated using 10-fold cross-validation and a test set. Feature vectors, which are obtained from a combination of three feature extractions, show the best performance in 10-fold cross-validation both under non-dimensional reduction and dimensional reduction by max-relevance-max-distance. Moreover, the reduced mixed feature method performs better than the non-reduced mixed feature technique. The feature vectors, which are a combination of SSF and K-Skip-N-Grams, show the best performance in the test set. Among these methods, mixed features exhibit superiority over the single features.

Chiral liquid chromatography-mass spectrometry (LC-MS/MS) method development for the detection of salbutamol in urine samples.

PubMed

Chan, Sue Hay; Lee, Warren; Asmawi, Mohd Zaini; Tan, Soo Choon

2016-07-01

A sequential solid-phase extraction (SPE) method was developed and validated using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) for the detection and quantification of salbutamol enantiomers in porcine urine. Porcine urine samples were hydrolysed with β-glucuronidase/arylsulfatase from Helix pomatia and then subjected to a double solid-phase extraction (SPE) first using the Abs-Elut Nexus SPE and then followed by the Bond Elut Phenylboronic Acid (PBA) SPE. The salbutamol enantiomers were separated using the Astec CHIROBIOTIC™ T HPLC column (3.0mm×100mm; 5μm) maintained at 15°C with a 15min isocratic run at a flow rate of 0.4mL/min. The mobile phase constituted of 5mM ammonium formate in methanol. Salbutamol and salbutamol-tert-butyl-d9 (internal standard, IS) was monitored and quantified with the multiple reaction monitoring (MRM) mode. The method showed good linearity for the range of 0.1-10ng/mL with limit of quantification at 0.3ng/mL. Analysis of the QC samples showed intra- and inter-assay precisions to be less than 5.04%, and recovery ranging from 83.82 to 102.33%. Copyright © 2016 Elsevier B.V. All rights reserved.

Flavanoid-rich fraction from Sageretia theezans leaves scavenges reactive oxygen radical species and increases the resistance of low-density lipoprotein to oxidation

USDA-ARS?s Scientific Manuscript database

To explore their bioactive fractions, S. theezans leaves were extracted 2 with 60% acetone and then fractionated sequentially with hexane, ethyl acetate, and water. ROS (HOCl, ONOO-, and O2 deg -) scavenging activity, ORAC value and total phenolic content of each fraction were investigated. The ethy...

A Permeable Active Amendment Concrete (PAAC) for Contaminant Remediation and Erosion Control

DTIC Science & Technology

2012-06-01

124: 131 -143. SRNL-STI-2012-00356 70 Tessier, A., Campbell, P.G.C., and Bisson, M. 1979. Sequential extraction procedure for the speciation of...Bulk Density, Dry, (AI( C-D)]* p, pcf 134.85 Bulk Dens ity after Immersion, [BI(C-D)]* p, pcf 146.65 Bulk Density after Immersion & Boiling1 jCI (C

Evaluation of the accessibility of CCA metals in liquefied CCA-treated wood sludge for recovery and reuse

Treesearch

Hui Pan; Todd F. Shupe; Chung-Yun Hse

2009-01-01

CCA-treated wood was liquefied with polyethylene glycol/glycerin and sulfuric acid. The heavy metals were precipitated by Ca(OH)2 from liquefied CCA-treated wood. The original CCA-treated wood and precipitated wood sludge were fractionated by a modified BCR (Community Bureau of Reference) sequential extraction procedure. The purpose of the BCR...

Geochemical and multi-isotopic ( 87Sr/ 86Sr, 143Nd/ 144Nd, 238U/ 235U) perspectives of sediment sources, depositional conditions, and diagenesis of the Marcellus Shale, Appalachian Basin, USA

DOE PAGES

Phan, Thai T.; Gardiner, James B.; Capo, Rosemary C.; ...

2017-10-25

Here, we investigate sediment sources, depositional conditions and diagenetic processes affecting the Middle Devonian Marcellus Shale in the Appalachian Basin, eastern USA, a major target of natural gas exploration. Multiple proxies, including trace metal contents, rare earth elements (REE), the Sm-Nd and Rb-Sr isotope systems, and U isotopes were applied to whole rock digestions and sequentially extracted fractions of the Marcellus shale and adjacent units from two locations in the Appalachian Basin. The narrow range of εNd values (from –7.8 to –6.4 at 390 Ma) is consistent with derivation of the clastic sedimentary component of the Marcellus Shale from amore » well-mixed source of fluvial and eolian material of the Grenville orogenic belt, and indicate minimal post-depositional alteration of the Sm-Nd system. While silicate minerals host >80% of the REE in the shale, data from sequentially extracted fractions reflect post-depositional modifications at the mineralogical scale, which is not observed in whole rock REE patterns.« less

Geochemical fractionation and pollution assessment of Zn, Cu, and Fe in surface sediments from Shadegan Wildlife Refuge, southwest of Iran.

PubMed

Chaharlang, Behnam Heidari; Bakhtiari, Alireza Riyahi; Mohammadi, Jahangard; Farshchi, Parvin

2017-09-01

This research focuses on the fractionation and distribution patterns of heavy metals (Zn, Cu, and Fe) in surficial sediments collected from Shadegan Wildlife Refuge, the biggest wetland in southern part of Iran, to provide an overall classification for the sources of metals in the study area using a sequential extraction method. For this purpose, a four-step sequential extraction technique was applied to define the partitioning of the metals into different geochemical phases of the sediment. The results illustrated that the average total level of Zn, Cu, and Fe in surface sediments were 55.20 ± 16.04, 22.86 ± 5.68, and 25,979.01 ± 6917.91 μg/g dw, respectively. On the average, the chemical partitioning of all metals in most stations was in the order of residual >oxidizable-organic > acid-reducible > exchangeable. In the same way, the results of calculated geochemical indices revealed that Cu, Zn, and Fe concentrations are mainly influenced by lithogenic origins. Compared with consensus-based SQGs, Cu was likely to result in occasionally harmful biological effects on the biota.

Characterization of co-products from producing ethanol by sequential extraction processing of corn

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

Hojilla-Evangelista, M.P.; Johnson, L.A.; Pometto, A.L. III

1996-12-31

Sequential Extraction Processing (SEP) is a new process for ethanol production that has potential to produce more valuable co-products than alternative processes. Previous work determined the yields of oil and protein and evaluated their chemical and functional properties. The properties of the crude fiber and spent solids, however, have yet to be studied. This research was conducted to evaluate the potential of SEP corn fiber to increase ethanol conversion and as replacement for gum arabic, and evaluate the potential of SEP starch and fiber to be fermented to ethanol. SEP hemicellulose from crude fiber was readily dispersible in water andmore » its solution (5%) gave low viscosity despite having high solids content. These properties indicated potential utilization as stabilizers, thickeners, and adhesive for coatings and batters in food and industrial products. Enzyme hydrolysis studies and batch fermentation of SEP starch/fiber indicated that SEP crude fiber was more readily accessible to the action of cellulases. More ethanol (about 10%) was produced from the fermentation of SEP starch/fiber than from undegermed or degermed soft dent corn, particularly when the hemicellulose fraction was absent from the SEP fiber.« less

Detection of Bacterial Pathogens from Broncho-Alveolar Lavage by Next-Generation Sequencing.

PubMed

Leo, Stefano; Gaïa, Nadia; Ruppé, Etienne; Emonet, Stephane; Girard, Myriam; Lazarevic, Vladimir; Schrenzel, Jacques

2017-09-20

The applications of whole-metagenome shotgun sequencing (WMGS) in routine clinical analysis are still limited. A combination of a DNA extraction procedure, sequencing, and bioinformatics tools is essential for the removal of human DNA and for improving bacterial species identification in a timely manner. We tackled these issues with a broncho-alveolar lavage (BAL) sample from an immunocompromised patient who had developed severe chronic pneumonia. We extracted DNA from the BAL sample with protocols based either on sequential lysis of human and bacterial cells or on the mechanical disruption of all cells. Metagenomic libraries were sequenced on Illumina HiSeq platforms. Microbial community composition was determined by k-mer analysis or by mapping to taxonomic markers. Results were compared to those obtained by conventional clinical culture and molecular methods. Compared to mechanical cell disruption, a sequential lysis protocol resulted in a significantly increased proportion of bacterial DNA over human DNA and higher sequence coverage of Mycobacterium abscessus , Corynebacterium jeikeium and Rothia dentocariosa , the bacteria reported by clinical microbiology tests. In addition, we identified anaerobic bacteria not searched for by the clinical laboratory. Our results further support the implementation of WMGS in clinical routine diagnosis for bacterial identification.

Geochemical and multi-isotopic ( 87Sr/ 86Sr, 143Nd/ 144Nd, 238U/ 235U) perspectives of sediment sources, depositional conditions, and diagenesis of the Marcellus Shale, Appalachian Basin, USA

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

Phan, Thai T.; Gardiner, James B.; Capo, Rosemary C.

Here, we investigate sediment sources, depositional conditions and diagenetic processes affecting the Middle Devonian Marcellus Shale in the Appalachian Basin, eastern USA, a major target of natural gas exploration. Multiple proxies, including trace metal contents, rare earth elements (REE), the Sm-Nd and Rb-Sr isotope systems, and U isotopes were applied to whole rock digestions and sequentially extracted fractions of the Marcellus shale and adjacent units from two locations in the Appalachian Basin. The narrow range of εNd values (from –7.8 to –6.4 at 390 Ma) is consistent with derivation of the clastic sedimentary component of the Marcellus Shale from amore » well-mixed source of fluvial and eolian material of the Grenville orogenic belt, and indicate minimal post-depositional alteration of the Sm-Nd system. While silicate minerals host >80% of the REE in the shale, data from sequentially extracted fractions reflect post-depositional modifications at the mineralogical scale, which is not observed in whole rock REE patterns.« less

Characterizing phosphorus speciation of Chesapeake Bay sediments using chemical extraction, 31P NMR, and X-ray absorption fine structure spectroscopy.

PubMed

Li, Wei; Joshi, Sunendra R; Hou, Guangjin; Burdige, David J; Sparks, Donald L; Jaisi, Deb P

2015-01-06

Nutrient contamination has been one of the lingering issues in the Chesapeake Bay because the bay restoration is complicated by temporally and seasonally variable nutrient sources and complex interaction between imported and regenerated nutrients. Differential reactivity of sedimentary phosphorus (P) pools in response to imposed biogeochemical conditions can record past sediment history and therefore a detailed sediment P speciation may provide information on P cycling particularly the stability of a P pool and the formation of one pool at the expense of another. This study examined sediment P speciation from three sites in the Chesapeake Bay: (i) a North site in the upstream bay, (ii) a middle site in the central bay dominated by seasonally hypoxic bottom water, and (iii) a South site at the bay-ocean boundary using a combination of sequential P extraction (SEDEX) and spectroscopic techniques, including (31)P NMR, P X-ray absorption near edge structure spectroscopy (XANES), and Fe extended X-ray absorption fine structure (EXAFS). Results from sequential P extraction reveal that sediment P is composed predominantly of ferric Fe-bound P and authigenic P, which was further confirmed by solid-state (31)P NMR, XANES, and EXAFS analyses. Additionally, solution (31)P NMR results show that the sediments from the middle site contain high amounts of organic P such as monoesters and diesters, compared to the other two sites, but that these compounds rapidly decrease with sediment depth indicating remineralized P could have precipitated as authigenic P. Fe EXAFS enabled to identify the changes in Fe mineral composition and P sinks in response to imposed redox condition in the middle site sediments. The presence of lepidocrocite, vermiculite, and Fe smectite in the middle site sediments indicates that some ferric Fe minerals can still be present along with pyrite and vivianite, and that ferric Fe-bound P pool can be a major P sink in anoxic sediments. These results provide improved insights into sediment P dynamics, particularly the rapid remineralization of organic P and the stability of Fe minerals and the ferric Fe-bound P pool in anoxic sediments in the Chesapeake Bay.

Decoding of finger trajectory from ECoG using deep learning.

PubMed

Xie, Ziqian; Schwartz, Odelia; Prasad, Abhishek

2018-06-01

Conventional decoding pipeline for brain-machine interfaces (BMIs) consists of chained different stages of feature extraction, time-frequency analysis and statistical learning models. Each of these stages uses a different algorithm trained in a sequential manner, which makes it difficult to make the whole system adaptive. The goal was to create an adaptive online system with a single objective function and a single learning algorithm so that the whole system can be trained in parallel to increase the decoding performance. Here, we used deep neural networks consisting of convolutional neural networks (CNN) and a special kind of recurrent neural network (RNN) called long short term memory (LSTM) to address these needs. We used electrocorticography (ECoG) data collected by Kubanek et al. The task consisted of individual finger flexions upon a visual cue. Our model combined a hierarchical feature extractor CNN and a RNN that was able to process sequential data and recognize temporal dynamics in the neural data. CNN was used as the feature extractor and LSTM was used as the regression algorithm to capture the temporal dynamics of the signal. We predicted the finger trajectory using ECoG signals and compared results for the least angle regression (LARS), CNN-LSTM, random forest, LSTM model (LSTM_HC, for using hard-coded features) and a decoding pipeline consisting of band-pass filtering, energy extraction, feature selection and linear regression. The results showed that the deep learning models performed better than the commonly used linear model. The deep learning models not only gave smoother and more realistic trajectories but also learned the transition between movement and rest state. This study demonstrated a decoding network for BMI that involved a convolutional and recurrent neural network model. It integrated the feature extraction pipeline into the convolution and pooling layer and used LSTM layer to capture the state transitions. The discussed network eliminated the need to separately train the model at each step in the decoding pipeline. The whole system can be jointly optimized using stochastic gradient descent and is capable of online learning.

Decoding of finger trajectory from ECoG using deep learning

NASA Astrophysics Data System (ADS)

Xie, Ziqian; Schwartz, Odelia; Prasad, Abhishek

2018-06-01

Objective. Conventional decoding pipeline for brain-machine interfaces (BMIs) consists of chained different stages of feature extraction, time-frequency analysis and statistical learning models. Each of these stages uses a different algorithm trained in a sequential manner, which makes it difficult to make the whole system adaptive. The goal was to create an adaptive online system with a single objective function and a single learning algorithm so that the whole system can be trained in parallel to increase the decoding performance. Here, we used deep neural networks consisting of convolutional neural networks (CNN) and a special kind of recurrent neural network (RNN) called long short term memory (LSTM) to address these needs. Approach. We used electrocorticography (ECoG) data collected by Kubanek et al. The task consisted of individual finger flexions upon a visual cue. Our model combined a hierarchical feature extractor CNN and a RNN that was able to process sequential data and recognize temporal dynamics in the neural data. CNN was used as the feature extractor and LSTM was used as the regression algorithm to capture the temporal dynamics of the signal. Main results. We predicted the finger trajectory using ECoG signals and compared results for the least angle regression (LARS), CNN-LSTM, random forest, LSTM model (LSTM_HC, for using hard-coded features) and a decoding pipeline consisting of band-pass filtering, energy extraction, feature selection and linear regression. The results showed that the deep learning models performed better than the commonly used linear model. The deep learning models not only gave smoother and more realistic trajectories but also learned the transition between movement and rest state. Significance. This study demonstrated a decoding network for BMI that involved a convolutional and recurrent neural network model. It integrated the feature extraction pipeline into the convolution and pooling layer and used LSTM layer to capture the state transitions. The discussed network eliminated the need to separately train the model at each step in the decoding pipeline. The whole system can be jointly optimized using stochastic gradient descent and is capable of online learning.

Fast determination of trace elements in organic fertilizers using a cup-horn reactor for ultrasound-assisted extraction and fast sequential flame atomic absorption spectrometry.

PubMed

Teixeira, Leonel Silva; Vieira, Heulla Pereira; Windmöller, Cláudia Carvalhinho; Nascentes, Clésia Cristina

2014-02-01

A fast and accurate method based on ultrasound-assisted extraction in a cup-horn sonoreactor was developed to determine the total content of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn in organic fertilizers by fast sequential flame atomic absorption spectrometry (FS FAAS). Multivariate optimization was used to establish the optimal conditions for the extraction procedure. An aliquot containing approximately 120 mg of the sample was added to a 500 µL volume of an acid mixture (HNO3/HCl/HF, 5:3:3, v/v/v). After a few minutes, 500 µL of deionized water was added and eight samples were simultaneously sonicated for 10 min at 50% amplitude, allowing a sample throughput of 32 extractions per hour. The performance of the method was evaluated with a certified reference material of sewage sludge (CRM 029). The precision, expressed as the relative standard deviation, ranged from 0.58% to 5.6%. The recoveries of analytes were found to 100%, 109%, 96%, 92%, 101%, 104% and 102% for Cd, Cr, Cu, Mn, Ni, Pb and Zn, respectively. The linearity, limit of detection and limit of quantification were calculated and the values obtained were adequate for the quality control of organic fertilizers. The method was applied to the analysis of several commercial organic fertilizers and organic wastes used as fertilizers, and the results were compared with those obtained using the microwave digestion procedure. A good agreement was found between the results obtained by microwave and ultrasound procedures with recoveries ranging from 80.4% to 117%. Two organic waste samples were not in accordance with the Brazilian legislation regarding the acceptable levels of contaminants. © 2013 Published by Elsevier B.V.

Comparison of efficacy and safety of levofloxacin-containing versus standard sequential therapy in eradication of Helicobacter pylori infection in Korea.

PubMed

Lee, Hyuk; Hong, Sung Noh; Min, Byung-Hoon; Lee, Jun Haeng; Rhee, Poong-Lyul; Lee, Yong Chan; Kim, Jae J

2015-02-01

Declining of eradication rates for Helicobacter pylori in Korea may be partly from the increasing prevalence of antibiotic resistance, especially clarithromycin resistance. To compare the efficacy and the safety of using 10-day standard sequential therapy and levofloxacin-containing sequential therapy as a first-line treatment for Helicobacter pylori eradication in Korea. A total of 200 patients with proven Helicobacter pylori infection randomly received 10-day standard sequential therapy (n = 100) or levofloxacin-containing sequential therapy (n = 100). The standard sequential therapy group received rabeprazole and amoxicillin for 5 days, followed by rabeprazole, clarithromycin, and metronidazole for 5 more days. The levofloxacin-containing sequential therapy group was treated with rabeprazole and amoxicillin for 5 days, followed by rabeprazole, levofloxacin, and metronidazole for 5 more days. Intention-to-treat eradication rates were 79.0% and 78.0% for groups of standard sequential and levofloxacin-containing sequential therapy, respectively (P = 0.863). Per-protocol eradication rates were 84.9% and 81.3%, respectively, for these two therapies (P = 0.498). There were no significant differences between the groups in regard to the eradication rates and adverse events. The 10-day levofloxacin-containing sequential regimen and the standard sequential regimen showed the similar eradication rates of Helicobacter pylori in Korea. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Detection of platinum species in plant material.

PubMed

Messerschmidt, J; Alt, F; Tölg, G

1995-05-01

Model experiments for the detection of platinum species in extracts from native and platinum-treated grass cultivations are described. The procedural steps are cultivation of the grass samples, extraction and concentration of the platinum species by ultrafiltration and freeze-drying, preparative separation of the species by gel chromatography followed by isotachophoresis, and sequential analytical detection of the separated platinum species by adsorptive voltammetry. After isotachophoresis, sharp peaks of platinum species could be detected. In the native grass extract only one platinum species (160-200 kDa) was found. In the platinum-treated grass extracts several platinum species were observed in the molecular mass range from 1 to > 1000 kDa. By an extremely sensitive platinum determination method (adsorptive voltammetry; detection limit, 2 pg Pt abs.) it was possible to detect platinum even in stained protein bands from horizontal gel electrophoresis of platinum containing fractions obtained after isotachophoresis.

Synergism between ultrasonic pretreatment and white rot fungal enzymes on biodegradation of wheat chaff.

PubMed

Sabarez, Henry; Oliver, Christine Maree; Mawson, Raymond; Dumsday, Geoff; Singh, Tanoj; Bitto, Natalie; McSweeney, Chris; Augustin, Mary Ann

2014-11-01

Lignocellulosic biomass samples (wheat chaff) were pretreated by ultrasound (US) (40kHz/0.5Wcm(-2)/10min and 400kHz/0.5Wcm(-2)/10min applied sequentially) prior to digestion by enzyme extracts obtained from fermentation of the biomass with white rot fungi (Phanerochaete chrysosporium or Trametes sp.). The accessibility of the cellulosic components in wheat chaff was increased, as demonstrated by the increased concentration of sugars produced by exposure to the ultrasound treatment prior to enzyme addition. Pretreatment with ultrasound increased the concentration of lignin degradation products (guaiacol and syringol) obtained from wheat chaff after enzyme addition. In vitro digestibility of wheat chaff was also enhanced by the ultrasonics pretreatment in combination with treatment with enzyme extracts. Degradation was enhanced with the use of a mixture of the enzyme extracts compared to that for a single enzyme extract. Copyright © 2014. Published by Elsevier B.V.

Anomalous gold, antimony, arsenic, and tungsten in ground water and alluvium around disseminated gold deposits along the Getchell Trend, Humboldt County, Nevada

USGS Publications Warehouse

Grimes, D.J.; Ficklin, W.H.; Meier, A.L.; McHugh, J.B.

1995-01-01

Ground-water, alluvium, and bedrock samples were collected from drill holes near the Chimney Creek, Preble, Summer Camp, and Rabbit Creek disseminated gold deposits in northern Nevada. Results of chemical analyses of drill-hole water samples show the presence of hydromorphic dispersion anomalies of Au, As, Sb, and W in the local ground-water systems associated with these deposits. In addition, analysis of sequential dissolution and extraction solutions of drill cuttings of alluvium and bedrock indicate geochemical anomalies of gold and ore-related metals in the overburden at depths corresponding to the location of the present-day water table. This relationship suggests that water-rock reactions around these buried deposits are active. -from Authors

Aggregating and Predicting Sequence Labels from Crowd Annotations

PubMed Central

Nguyen, An T.; Wallace, Byron C.; Li, Junyi Jessy; Nenkova, Ani; Lease, Matthew

2017-01-01

Despite sequences being core to NLP, scant work has considered how to handle noisy sequence labels from multiple annotators for the same text. Given such annotations, we consider two complementary tasks: (1) aggregating sequential crowd labels to infer a best single set of consensus annotations; and (2) using crowd annotations as training data for a model that can predict sequences in unannotated text. For aggregation, we propose a novel Hidden Markov Model variant. To predict sequences in unannotated text, we propose a neural approach using Long Short Term Memory. We evaluate a suite of methods across two different applications and text genres: Named-Entity Recognition in news articles and Information Extraction from biomedical abstracts. Results show improvement over strong baselines. Our source code and data are available online1. PMID:29093611

Improved radiocarbon analyses of modern human hair to determine the year-of-death by cross-flow nanofiltered amino acids: common contaminants, implications for isotopic analysis, and recommendations.

PubMed

Santos, Guaciara M; De La Torre, Hector A Martinez; Boudin, Mathieu; Bonafini, Marco; Saverwyns, Steven

2015-10-15

In forensic investigation, radiocarbon ((14)C) measurements of human tissues (i.e., nails and hair) can help determine the year-of-death. However, the frequent use of cosmetics can bias hair (14)C results as well as stable isotope values. Evidence shows that hair exogenous impurities percolate beyond the cuticle layer, and therefore conventional pretreatments are ineffective in removing them. We conducted isotopic analysis ((14)C, δ(13)C, δ(15)N and C/N) of conventionally treated and cross-flow nanofiltered amino acid (CFNAA)-treated samples (scalp- and body-hair) from a single female subject using fingernails as a reference. The subject studied frequently applies a permanent dark-brown dye kit to her scalp-hair and uses other care products for daily cleansing. We also performed pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) analyses of CFNAA-treated scalp-hair to identify contaminant remnants that could possibly interfere with isotopic analyses. The conventionally treated scalp- and body-hair showed (14)C offsets of ~21‰ and ~9‰, respectively. These offsets confirm the contamination by petrochemicals in modern human hair. A single CFNAA extraction reduced those offsets by ~34%. No significant improvement was observed when sequential extractions were performed, as it appears that the procedure introduced some foreign contaminants. A chromatogram of the CFNAA scalp-hair pyrolysis products showed the presence of petroleum and plant/animal compound residues, which can bias isotopic analyses. We have demonstrated that CFNAA extractions can partially remove cosmetic contaminants embedded in human hair. We conclude that fingernails are still the best source of keratin protein for year-of-death determinations and isotopic analysis, with body-hair and/or scalp-hair coupled with CFNAA extraction a close second. Copyright © 2015 John Wiley & Sons, Ltd.

Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Agaricomycetes), Inhibits Candida Biofilms: A Metabolomic Approach.

PubMed

Bhardwaj, Anuja; Gupta, Payal; Kumar, Navin; Mishra, Jigni; Kumar, Ajai; Rakhee, Rajput; Misra, Kshipra

2017-01-01

This article presents a comparative gas chromatography (GC)-mass spectrometry (MS)-based metabolomic analysis of mycelia and fruiting bodies of the medicinal mushroom Ganoderma lucidum. Three aqueous extracts-mycelia, fruiting bodies, and a mixture of them-and their sequential fractions (methanolic and ethyl acetate), prepared using an accelerated solvent extractor, were characterized by GC-MS to determine volatile organic compounds and by high-performance thin-layer chromatography to quantify ascorbic acid, a potent antioxidant. In addition, these extracts and fractions were assessed against Candida albicans and C. glabrata biofilms via the XTT reduction assay, and their antioxidant potential was evaluated. Application of chemometrics (hierarchical cluster analysis and principal component analysis) to GC data revealed variability in volatile organic compound profiles among G. lucidum extracts and fractions. The mycelial aqueous extract demonstrated higher anti-Candida activity and ascorbic acid content among all the extracts and fractions. Thus, this study illustrates the preventive effect of G. lucidum against C. albicans and C. glabrata biofilms along with its nutritional value.

In-line micro-matrix solid-phase dispersion extraction for simultaneous separation and extraction of Sudan dyes in different spices.

PubMed

Rajabi, Maryam; Sabzalian, Sedigheh; Barfi, Behruz; Arghavani-Beydokhti, Somayeh; Asghari, Alireza

2015-12-18

A novel, simple, fast, and miniaturized method, termed in-line micro-matrix solid-phase dispersion (in-line MMSPD), coupled with high performance liquid chromatography (HPLC) was developed for the simultaneous extraction and determination of Sudan dyes (i.e. Sudan I-IV, Sudan orange G, Sudan black B, and Sudan red G) with the aid of an experimental design strategy. In this method, a matrix solid-phase dispersion (MSPD) column including a suitable mixture of polar sorbents was inserted in the mobile phase pathway, and while the interfering compounds were retained, the analytes were eluted and entered into the analytical column. In this way, the extraction, elution, and separation of the analytes were performed sequentially. Under the optimal experimental conditions (including the amount of sample, 0.0426g; amount of dispersant phase, 0.0216g of florisil, 0.0227g of silica, 0.0141g of alumina; and blending time, 112s), the limits of detection (LODs), limits of quantification, linear dynamic ranges, and recoveries were obtained to be 0.3-15.3μgkg(-1), 1-50μgkg(-1), 50-28,000μgkg(-1), and 94.5-99.1%, respectively. The results obtained showed that determination of the selected Sudan dyes in food samples using an enough sensitive and a simple analytically validated method like in-line MMSPD may offer a suitable screening method, which could be useful for food analysis and adulteration. Copyright © 2015 Elsevier B.V. All rights reserved.

Capsicum annuum var. grossum (Bell Pepper) Inhibits β-Secretase Activity and β-Amyloid1-40 Aggregation.

PubMed

Ogunruku, Omodesola Oluwafisayo; Oboh, Ganiyu; Passamonti, Sabina; Trammer, Federica; Boligon, Aline Augusti

2017-02-01

The deposition of amyloid protein as senile plaques is the major signature of Alzheimer's disease (AD). It is produced by the sequential cleavage of the amyloid precursor protein by secretases. Moreover, peppers are noted for their antiaging and cognitive enhancing properties. Thus, in this study, the effects of polyphenol-rich extracts from bell pepper on amyloid production and aggregation in vitro were investigated. Bell pepper (ripe and unripe) was extracted with methanol-1 N HCl (1:1 v/v). Thereafter, the inhibitory potentials of the extracts on β-secretase and β-amyloid 1-40 aggregation were determined. Phenolic composition of the pepper fruits was further determined by HPLC-DAD (high performance liquid chromatography-diode array detector). There was a dose-dependent inhibition of β-secretase by the pepper fruits with the ripe fruits (2.17 ± 0.17 μg/L) showing a significantly (P < .05) higher inhibitory effect than the unripe (3.44 ± 0.11 μg/L). Furthermore, Thioflavin-T and transmission electron microscopy analyses revealed that phenolic extracts from pepper fruits (1 and 10 μg/L) could counteract the initial aggregation of Aβ 1-40 , as well as prevent further aggregation preformed fibrils. These inhibitory activities could be attributed to the predominant presence of phenolic constituents in the pepper fruits. It is possible to conclude that bell pepper could be a possible dietary intervention into the management of AD.

Chemical characterisation of dredged sediments in relation to their potential use in civil engineering.

PubMed

Zuliani, Tea; Mladenovič, Ana; Ščančar, Janez; Milačič, Radmila

2016-04-01

During capital and/or maintenance dredging operations, large amounts of material are produced. Instead of their discharge, dredged sediments may be a valuable natural resource if not contaminated. One of the possible areas of application is civil engineering. In the present work, the environmental status of seaport dredged sediment was evaluated in order to investigate its potential applicability as a secondary raw material. Sediments were analysed for element concentrations in digested samples, aqueous extracts and fractions from sequential extraction; for fluoride, chloride and sulphate concentrations in aqueous extracts; and for tributyltin (TBT). Granulometric and mineralogical compositions were also analysed. The elemental impact was evaluated by calculation of the enrichment factors. The total element concentrations determined showed moderate contamination of the dredged sediments as was confirmed also by their moderate enrichment factors, presumably as a result of industrial and port activities. Elemental concentrations in the aqueous extract were very low and therefore do not represent any hazard for the environment. The water-soluble element concentrations were under the threshold levels set by the EU Directive on the landfill of waste, on the basis of which the applicability of dredged sediments in civil engineering is evaluated, while the content of chloride and sulphate were above the threshold levels. It was found out that due to the large amounts of sediment available, civil engineering applications such as the construction of embankments and backfilling is the most beneficial recycling solution at present.

Isolation, purification, and partial characterization of Brucella abortus matrix protein.

PubMed Central

Moriyon, I; Berman, D T

1983-01-01

Peptidoglycan sacculi with peptidoglycan-associated proteins were prepared from cell envelopes of Brucella abortus by extraction with sodium dodecyl sulfate (SDS) at 50 degrees C. On extraction of these preparations with SDS at 100 degrees C, a protein was obtained whose removal from peptidoglycan was confirmed by electron microscopy. Incubation of the 50 degrees C SDS-extracted cell envelopes with 50 mM MgCl2 in SDS-2-beta-mercaptoethanol at 37 degrees C also extracted the protein, along with lipopolysaccharide. At temperatures below 60 degrees C, the protein did not bind SDS strongly and had an apparent molecular weight greater than 92,000 in SDS-polyacrylamide gel electrophoresis. At higher temperatures, SDS bound strongly, and the apparent molecular weight was 38,000. Urea at 5 M did not alter the electrophoretic mobility of this 38,000-molecular-weight form. Immunoelectrophoresis in detergents with antisera to cell envelopes, carbohydrate staining of SDS-polyacrylamide gels, and production of anti-lipopolysaccharide antibodies by mice immunized with the purified protein indicated that lipopolysaccharide was present in free and protein-bound forms. Sequential gel filtration in SDS-EDTA and SDS-NaCl removed most lipopolysaccharide. After further purification by preparative SDS-polyacrylamide gel electrophoresis, a gas-liquid chromatographic analysis showed residual lipid tightly associated with the protein. The results suggested that the interactions between matrix proteins and other outer membrane components are stronger in B. abortus than in Escherichia coli, which was used as a control throughout. Images PMID:6401696

Multilayer neural networks for reduced-rank approximation.

PubMed

Diamantaras, K I; Kung, S Y

1994-01-01

This paper is developed in two parts. First, the authors formulate the solution to the general reduced-rank linear approximation problem relaxing the invertibility assumption of the input autocorrelation matrix used by previous authors. The authors' treatment unifies linear regression, Wiener filtering, full rank approximation, auto-association networks, SVD and principal component analysis (PCA) as special cases. The authors' analysis also shows that two-layer linear neural networks with reduced number of hidden units, trained with the least-squares error criterion, produce weights that correspond to the generalized singular value decomposition of the input-teacher cross-correlation matrix and the input data matrix. As a corollary the linear two-layer backpropagation model with reduced hidden layer extracts an arbitrary linear combination of the generalized singular vector components. Second, the authors investigate artificial neural network models for the solution of the related generalized eigenvalue problem. By introducing and utilizing the extended concept of deflation (originally proposed for the standard eigenvalue problem) the authors are able to find that a sequential version of linear BP can extract the exact generalized eigenvector components. The advantage of this approach is that it's easier to update the model structure by adding one more unit or pruning one or more units when the application requires it. An alternative approach for extracting the exact components is to use a set of lateral connections among the hidden units trained in such a way as to enforce orthogonality among the upper- and lower-layer weights. The authors call this the lateral orthogonalization network (LON) and show via theoretical analysis-and verify via simulation-that the network extracts the desired components. The advantage of the LON-based model is that it can be applied in a parallel fashion so that the components are extracted concurrently. Finally, the authors show the application of their results to the solution of the identification problem of systems whose excitation has a non-invertible autocorrelation matrix. Previous identification methods usually rely on the invertibility assumption of the input autocorrelation, therefore they can not be applied to this case.

Purification and structural characterization of Chinese yam polysaccharide and its activities.

PubMed

Yang, Weifang; Wang, Ying; Li, Xiuping; Yu, Ping

2015-03-06

Purification and structural characterization of Chinese yam polysaccharide were investigated and its activities were analyzed. Results indicated that a single component polysaccharide with a molecular weight of 16,619 Da was obtained after hot water extraction with sequential sevage deproteinization, HSCCC and Sephadex G-100 size-exclusion chromatography. The FTIR analysis showed that it had characteristic absorptive peaks and contained uronic acid. The methylation and GC-MS analysis showed that it comprised of glucose and galactose with a molar ratio of 1.52:1, and that it mainly contained 1,3-linked-glc, 1-linked-gal and 1,6-linked-gal glycosidic bonds. (1)H NMR and (13)C NMR spectra analysis showed that there were two α-configurations and one β-configuration, and that β-1,3-glucose, α-1-galactose, α-1,6-galactose might exist in the structure of the purified polysaccharide. The determination of the antioxidative activity showed that it could scavenge hydroxyl and superoxide radicals. The purified polysaccharide displayed a certain inhibitory activity against Escherichia coli, with a MIC of 2.5 mg/mL. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sequential Extraction as Novel Approach to Compare 12 Medicinal Plants From Kenya Regarding Their Potential to Release Chromium, Manganese, Copper, and Zinc.

PubMed

Mogwasi, R; Zor, S; Kariuki, D K; Getenga, M Z; Nischwitz, V

2018-04-01

This study is focusing on a novel approach to screen a large number of medicinal plants from Kenya regarding their contents and availability of selected metals potentially relevant for treatment of diabetes patients. For this purpose, total levels of zinc, chromium, manganese, and copper were determined by flame atomic absorption spectrometry and inductively coupled plasma mass spectrometry as well as BCR sequential extraction to fractionate the elemental species in anti-diabetic medicinal plants collected from five natural locations in two sub counties in Nyamira County, Kenya. Solanum mauense had the highest zinc level of 123.0 ± 3.1 mg/kg while Warburgia ugandensis had the lowest level of 13.9 ± 0.4 mg/kg. The highest level of copper was in Bidens pilosa (29.0 ± 0.6 mg/kg) while the lowest was in Aloe vera (3.0 ± 0.1 mg/kg). Croton macrostachyus had the highest manganese level of 1630 ± 40 mg/kg while Clerodendrum myricoides had the lowest (80.2 ± 1.2 mg/kg). The highest level of chromium was in Solanum mauense (3.20 ± 0.06 mg/kg) while the lowest (0.04 ± 0.01 mg/kg) were in Clerodendrum myricoides and Warburgia ugandesis among the medicinal plants from Nyamira and Borabu, respectively. The levels of the elements were statistically different from that of other elements while the level of a given element was not statistically different in the medicinal plants from the different sub counties. Sequential extraction was performed to determine the solubility and thus estimate the bioavailability of the four investigated essential and potentially therapeutically relevant metals. The results showed that the easily bioavailable fraction (EBF) of chromium, manganese, zinc, and copper ranged from 6.7 to 13.8%, 4.1 to 10%, 2.4 to 10.2%, and 3.2 to 12.0% while the potentially bioavailable fraction (PBF) ranged from 50.1 to 67.6%, 32.2 to 48.7%, 23.0 to 41.1%, and 34.6 to 53.1%, respectively. Bidens pilosa, Croton macrostachyus, Ultrica dioica, and Solanum mauense medicinal plants used to treat diabetes by 80 % of the herbalists in Nyamira County were found to be rich in chromium, manganese, copper, and zinc. The EBF of zinc, manganese, and chromium constitutes adequate amounts recommended for daily intake not exceeding the ADI and delivered a low percentage of RDA when estimating daily intake during therapy from typically applied doses. The plants did not show any significant differences at p < 0.05 in terms of concentrations of the elements between the two study areas though the levels of the different elements were statistically significant. Another major observation was that high total levels of the metals in a given plant did not necessarily translate to high bioavailable levels, and hence the need to determine bioavailable form as it is the one accessible to the patient.

Evaluation of Robustness to Setup and Range Uncertainties for Head and Neck Patients Treated With Pencil Beam Scanning Proton Therapy

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

Malyapa, Robert; Lowe, Matthew; Christie Medical Physics and Engineering, The Christie NHS Foundation Trust, Manchester

Purpose: To evaluate the robustness of head and neck plans for treatment with intensity modulated proton therapy to range and setup errors, and to establish robustness parameters for the planning of future head and neck treatments. Methods and Materials: Ten patients previously treated were evaluated in terms of robustness to range and setup errors. Error bar dose distributions were generated for each plan, from which several metrics were extracted and used to define a robustness database of acceptable parameters over all analyzed plans. The patients were treated in sequentially delivered series, and plans were evaluated for both the first seriesmore » and for the combined error over the whole treatment. To demonstrate the application of such a database in the head and neck, for 1 patient, an alternative treatment plan was generated using a simultaneous integrated boost (SIB) approach and plans of differing numbers of fields. Results: The robustness database for the treatment of head and neck patients is presented. In an example case, comparison of single and multiple field plans against the database show clear improvements in robustness by using multiple fields. A comparison of sequentially delivered series and an SIB approach for this patient show both to be of comparable robustness, although the SIB approach shows a slightly greater sensitivity to uncertainties. Conclusions: A robustness database was created for the treatment of head and neck patients with intensity modulated proton therapy based on previous clinical experience. This will allow the identification of future plans that may benefit from alternative planning approaches to improve robustness.« less

Sequential memory: Binding dynamics

NASA Astrophysics Data System (ADS)

Afraimovich, Valentin; Gong, Xue; Rabinovich, Mikhail

2015-10-01

Temporal order memories are critical for everyday animal and human functioning. Experiments and our own experience show that the binding or association of various features of an event together and the maintaining of multimodality events in sequential order are the key components of any sequential memories—episodic, semantic, working, etc. We study a robustness of binding sequential dynamics based on our previously introduced model in the form of generalized Lotka-Volterra equations. In the phase space of the model, there exists a multi-dimensional binding heteroclinic network consisting of saddle equilibrium points and heteroclinic trajectories joining them. We prove here the robustness of the binding sequential dynamics, i.e., the feasibility phenomenon for coupled heteroclinic networks: for each collection of successive heteroclinic trajectories inside the unified networks, there is an open set of initial points such that the trajectory going through each of them follows the prescribed collection staying in a small neighborhood of it. We show also that the symbolic complexity function of the system restricted to this neighborhood is a polynomial of degree L - 1, where L is the number of modalities.

Sequential memory: Binding dynamics.

PubMed

Afraimovich, Valentin; Gong, Xue; Rabinovich, Mikhail

2015-10-01

Temporal order memories are critical for everyday animal and human functioning. Experiments and our own experience show that the binding or association of various features of an event together and the maintaining of multimodality events in sequential order are the key components of any sequential memories-episodic, semantic, working, etc. We study a robustness of binding sequential dynamics based on our previously introduced model in the form of generalized Lotka-Volterra equations. In the phase space of the model, there exists a multi-dimensional binding heteroclinic network consisting of saddle equilibrium points and heteroclinic trajectories joining them. We prove here the robustness of the binding sequential dynamics, i.e., the feasibility phenomenon for coupled heteroclinic networks: for each collection of successive heteroclinic trajectories inside the unified networks, there is an open set of initial points such that the trajectory going through each of them follows the prescribed collection staying in a small neighborhood of it. We show also that the symbolic complexity function of the system restricted to this neighborhood is a polynomial of degree L - 1, where L is the number of modalities.

Breast conserving treatment for breast cancer: dosimetric comparison of sequential versus simultaneous integrated photon boost.

PubMed

Van Parijs, Hilde; Reynders, Truus; Heuninckx, Karina; Verellen, Dirk; Storme, Guy; De Ridder, Mark

2014-01-01

Breast conserving surgery followed by whole breast irradiation is widely accepted as standard of care for early breast cancer. Addition of a boost dose to the initial tumor area further reduces local recurrences. We investigated the dosimetric benefits of a simultaneously integrated boost (SIB) compared to a sequential boost to hypofractionate the boost volume, while maintaining normofractionation on the breast. For 10 patients 4 treatment plans were deployed, 1 with a sequential photon boost, and 3 with different SIB techniques: on a conventional linear accelerator, helical TomoTherapy, and static TomoDirect. Dosimetric comparison was performed. PTV-coverage was good in all techniques. Conformity was better with all SIB techniques compared to sequential boost (P = 0.0001). There was less dose spilling to the ipsilateral breast outside the PTVboost (P = 0.04). The dose to the organs at risk (OAR) was not influenced by SIB compared to sequential boost. Helical TomoTherapy showed a higher mean dose to the contralateral breast, but less than 5 Gy for each patient. SIB showed less dose spilling within the breast and equal dose to OAR compared to sequential boost. Both helical TomoTherapy and the conventional technique delivered acceptable dosimetry. SIB seems a safe alternative and can be implemented in clinical routine.

Breast Conserving Treatment for Breast Cancer: Dosimetric Comparison of Sequential versus Simultaneous Integrated Photon Boost

PubMed Central

Reynders, Truus; Heuninckx, Karina; Verellen, Dirk; Storme, Guy; De Ridder, Mark

2014-01-01

Background. Breast conserving surgery followed by whole breast irradiation is widely accepted as standard of care for early breast cancer. Addition of a boost dose to the initial tumor area further reduces local recurrences. We investigated the dosimetric benefits of a simultaneously integrated boost (SIB) compared to a sequential boost to hypofractionate the boost volume, while maintaining normofractionation on the breast. Methods. For 10 patients 4 treatment plans were deployed, 1 with a sequential photon boost, and 3 with different SIB techniques: on a conventional linear accelerator, helical TomoTherapy, and static TomoDirect. Dosimetric comparison was performed. Results. PTV-coverage was good in all techniques. Conformity was better with all SIB techniques compared to sequential boost (P = 0.0001). There was less dose spilling to the ipsilateral breast outside the PTVboost (P = 0.04). The dose to the organs at risk (OAR) was not influenced by SIB compared to sequential boost. Helical TomoTherapy showed a higher mean dose to the contralateral breast, but less than 5 Gy for each patient. Conclusions. SIB showed less dose spilling within the breast and equal dose to OAR compared to sequential boost. Both helical TomoTherapy and the conventional technique delivered acceptable dosimetry. SIB seems a safe alternative and can be implemented in clinical routine. PMID:25162031

Determination of cadmium and lead in table salt by sequential multi-element flame atomic absorption spectrometry.

PubMed

Amorim, Fábio A C; Ferreira, Sérgio L C

2005-02-28

In the present paper, a simultaneous pre-concentration procedure for the sequential determination of cadmium and lead in table salt samples using flame atomic absorption spectrometry is proposed. This method is based on the liquid-liquid extraction of cadmium(II) and lead(II) ions as dithizone complexes and direct aspiration of the organic phase for the spectrometer. The sequential determination of cadmium and lead is possible using a computer program. The optimization step was performed by a two-level fractional factorial design involving the variables: pH, dithizone mass, shaking time after addition of dithizone and shaking time after addition of solvent. In the studied levels these variables are not significant. The experimental conditions established propose a sample volume of 250mL and the extraction process using 4.0mL of methyl isobutyl ketone. This way, the procedure allows determination of cadmium and lead in table salt samples with a pre-concentration factor higher than 80, and detection limits of 0.3ngg(-1) for cadmium and 4.2ngg(-1) for lead. The precision expressed as relative standard deviation (n = 10) were 5.6 and 2.6% for cadmium concentration of 2 and 20ngg(-1), respectively, and of 3.2 and 1.1% for lead concentration of 20 and 200ngg(-1), respectively. Recoveries of cadmium and lead in several samples, measured by standard addition technique, proved also that this procedure is not affected by the matrix and can be applied satisfactorily for the determination of cadmium and lead in saline samples. The method was applied for the evaluation of the concentration of cadmium and lead in table salt samples consumed in Salvador City, Bahia, Brazil.

Vigi4Med Scraper: A Framework for Web Forum Structured Data Extraction and Semantic Representation

PubMed Central

Audeh, Bissan; Beigbeder, Michel; Zimmermann, Antoine; Jaillon, Philippe; Bousquet, Cédric

2017-01-01

The extraction of information from social media is an essential yet complicated step for data analysis in multiple domains. In this paper, we present Vigi4Med Scraper, a generic open source framework for extracting structured data from web forums. Our framework is highly configurable; using a configuration file, the user can freely choose the data to extract from any web forum. The extracted data are anonymized and represented in a semantic structure using Resource Description Framework (RDF) graphs. This representation enables efficient manipulation by data analysis algorithms and allows the collected data to be directly linked to any existing semantic resource. To avoid server overload, an integrated proxy with caching functionality imposes a minimal delay between sequential requests. Vigi4Med Scraper represents the first step of Vigi4Med, a project to detect adverse drug reactions (ADRs) from social networks founded by the French drug safety agency Agence Nationale de Sécurité du Médicament (ANSM). Vigi4Med Scraper has successfully extracted greater than 200 gigabytes of data from the web forums of over 20 different websites. PMID:28122056

Dynamic leaching and fractionation of trace elements from environmental solids exploiting a novel circulating-flow platform.

PubMed

Mori, Masanobu; Nakano, Koji; Sasaki, Masaya; Shinozaki, Haruka; Suzuki, Shiho; Okawara, Chitose; Miró, Manuel; Itabashi, Hideyuki

2016-02-01

A dynamic flow-through microcolumn extraction system based on extractant re-circulation is herein proposed as a novel analytical approach for simplification of bioaccessibility tests of trace elements in sediments. On-line metal leaching is undertaken in the format of all injection (AI) analysis, which is a sequel of flow injection analysis, but involving extraction under steady-state conditions. The minimum circulation times and flow rates required to determine the maximum bioaccessible pools of target metals (viz., Cu, Zn, Cd, and Pb) from lake and river sediment samples were estimated using Tessier's sequential extraction scheme and an acid single extraction test. The on-line AIA method was successfully validated by mass balance studies of CRM and real sediment samples. Tessier's test in on-line AI format demonstrated to be carried out by one third of extraction time (6h against more than 17 h by the conventional method), with better analytical precision (<9.2% against >15% by the conventional method) and significant decrease in blank readouts as compared with the manual batch counterpart. Copyright © 2015 Elsevier B.V. All rights reserved.

Automated process for solvent separation of organic/inorganic substance

DOEpatents

Schweighardt, F.K.

1986-07-29

There is described an automated process for the solvent separation of organic/inorganic substances that operates continuously and unattended and eliminates potential errors resulting from subjectivity and the aging of the sample during analysis. In the process, metered amounts of one or more solvents are passed sequentially through a filter containing the sample under the direction of a microprocessor control apparatus. The mixture in the filter is agitated by ultrasonic cavitation for a timed period and the filtrate is collected. The filtrate of each solvent extraction is collected individually and the residue on the filter element is collected to complete the extraction process. 4 figs.

Automated process for solvent separation of organic/inorganic substance

DOEpatents

Schweighardt, Frank K.

1986-01-01

There is described an automated process for the solvent separation of organic/inorganic substances that operates continuously and unattended and eliminates potential errors resulting from subjectivity and the aging of the sample during analysis. In the process, metered amounts of one or more solvents are passed sequentially through a filter containing the sample under the direction of a microprocessor control apparatus. The mixture in the filter is agitated by ultrasonic cavitation for a timed period and the filtrate is collected. The filtrate of each solvent extraction is collected individually and the residue on the filter element is collected to complete the extraction process.

Automated apparatus for solvent separation of a coal liquefaction product stream

DOEpatents

Schweighardt, Frank K.

1985-01-01

An automated apparatus for the solvent separation of a coal liquefaction product stream that operates continuously and unattended and eliminates potential errors resulting from subjectivity and the aging of the sample during analysis. In use of the apparatus, metered amounts of one or more solvents are passed sequentially through a filter containing the sample under the direction of a microprocessor control means. The mixture in the filter is agitated by means of ultrasonic cavitation for a timed period and the filtrate is collected. The filtrate of each solvent extraction is collected individually and the residue on the filter element is collected to complete the extraction process.

Sequential search leads to faster, more efficient fragment-based de novo protein structure prediction.

PubMed

de Oliveira, Saulo H P; Law, Eleanor C; Shi, Jiye; Deane, Charlotte M

2018-04-01

Most current de novo structure prediction methods randomly sample protein conformations and thus require large amounts of computational resource. Here, we consider a sequential sampling strategy, building on ideas from recent experimental work which shows that many proteins fold cotranslationally. We have investigated whether a pseudo-greedy search approach, which begins sequentially from one of the termini, can improve the performance and accuracy of de novo protein structure prediction. We observed that our sequential approach converges when fewer than 20 000 decoys have been produced, fewer than commonly expected. Using our software, SAINT2, we also compared the run time and quality of models produced in a sequential fashion against a standard, non-sequential approach. Sequential prediction produces an individual decoy 1.5-2.5 times faster than non-sequential prediction. When considering the quality of the best model, sequential prediction led to a better model being produced for 31 out of 41 soluble protein validation cases and for 18 out of 24 transmembrane protein cases. Correct models (TM-Score > 0.5) were produced for 29 of these cases by the sequential mode and for only 22 by the non-sequential mode. Our comparison reveals that a sequential search strategy can be used to drastically reduce computational time of de novo protein structure prediction and improve accuracy. Data are available for download from: http://opig.stats.ox.ac.uk/resources. SAINT2 is available for download from: https://github.com/sauloho/SAINT2. saulo.deoliveira@dtc.ox.ac.uk. Supplementary data are available at Bioinformatics online.

[Bilateral cochlear implants in children: acquisition of binaural hearing].

PubMed

Ramos-Macías, Angel; Deive-Maggiolo, Leopoldo; Artiles-Cabrera, Ovidio; González-Aguado, Rocío; Borkoski-Barreiro, Silvia A; Masgoret-Palau, Elizabeth; Falcón-González, Juan C; Bueno-Yanes, Jorge

2013-01-01

Several studies have indicated the benefit of bilateral cochlear implants in the acquisition of binaural hearing and bilateralism. In children with cochlear implants, is it possible to achieve binaurality after a second implant? When is the ideal time to implant them? The objective of this study was to analyse the binaural effect in children with bilateral implants and the differences between subjects with simultaneous and sequential implants with both short and long intervals. There were 90 patients between 1 and 2 years of age (the first surgery), implanted between 2000 and 2008. Of these, 25 were unilateral users and 65 bilateral; 17 patients had received simultaneous implants, 29 had sequential implants before 12 months after the first one (short interimplant period) and 19 after 12 months (long period). All of them were tested for silent and noisy verbal perception and a tonal threshold audiometry was performed. The silent perception test showed that the simultaneous and short period sequential implant patients (mean: 84.67%) versus unilateral and long period sequential implants (mean: 79.66%), had a statistically-significant difference (P=0,23). Likewise, the noisy perception test showed a difference with statistical significance (P=0,22) comparing the simultaneous implanted and short period sequential implants (mean, 77.17%) versus unilateral implanted and long period sequential ones (mean: 69.32%). The simultaneous and sequential short period implants acquired the advantages of binaural hearing. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Analytical Method for Determining Tetrazene in Water.

DTIC Science & Technology

1987-12-01

8217-decanesulfonic acid sodium salt. The mobile phase pH was adjusted to 3 with glacial acetic acid. The modified mobile phase was optimal for separating of...modified with sodium tartrate, gave a well-defined reduction wave at the dropping mercury electrode. The height of the reduction wave was proportional to...anitmony trisulphide, nitrocellulose, PETN, powdered aluminum and calcium silicide . The primer samples were sequentially extracted, first with

Soil Phosphorus Fractionation during Forest Development on Landslide Scars in the Luquillo Mountains, Puerto Rico.

Treesearch

Jacqueline Frizano; Arthur H. Johnson; David R. Vann; Frederick N. Scatena

2002-01-01

Mineral soils from a chronosequence of landslide scars ranging in age from 1 to more than 55 years in a subtropical montane rain forest of eastern Puerto Rico were used to determine the rate at which labile P capital recovers during primary succession. Nine organic and inorganic soil P fractions were measured using the Hedley sequential extraction procedure. Deep soil...

Fractionation of heavy metals in liquefied chromated copper arsenate (CCA)-treated wood sludge using a modified BCR-sequential extraction procedure

Treesearch

Hui Pan; Chung-Yun Hse; Robert Gambrell; Todd F. Shupe

2009-01-01

Chromated copper arsenate (CCA)-treated wood was liquefied with polyethylene glycol/glycerin and sulfuric acid. After liquefaction, most CCA metals (98% As, 92% Cr, and 83% Cu) were removed from liquefied CCA-treated wood by precipitation with calcium hydroxide. The original CCA-treated wood and liquefied CCA-treated wood sludge were fractionated by a modified...

Feature Extraction in Sequential Multimedia Images: with Applications in Satellite Images and On-line Videos

NASA Astrophysics Data System (ADS)

Liang, Yu-Li

Multimedia data is increasingly important in scientific discovery and people's daily lives. Content of massive multimedia is often diverse and noisy, and motion between frames is sometimes crucial in analyzing those data. Among all, still images and videos are commonly used formats. Images are compact in size but do not contain motion information. Videos record motion but are sometimes too big to be analyzed. Sequential images, which are a set of continuous images with low frame rate, stand out because they are smaller than videos and still maintain motion information. This thesis investigates features in different types of noisy sequential images, and the proposed solutions that intelligently combined multiple features to successfully retrieve visual information from on-line videos and cloudy satellite images. The first task is detecting supraglacial lakes above ice sheet in sequential satellite images. The dynamics of supraglacial lakes on the Greenland ice sheet deeply affect glacier movement, which is directly related to sea level rise and global environment change. Detecting lakes above ice is suffering from diverse image qualities and unexpected clouds. A new method is proposed to efficiently extract prominent lake candidates with irregular shapes, heterogeneous backgrounds, and in cloudy images. The proposed system fully automatize the procedure that track lakes with high accuracy. We further cooperated with geoscientists to examine the tracked lakes and found new scientific findings. The second one is detecting obscene content in on-line video chat services, such as Chatroulette, that randomly match pairs of users in video chat sessions. A big problem encountered in such systems is the presence of flashers and obscene content. Because of various obscene content and unstable qualities of videos capture by home web-camera, detecting misbehaving users is a highly challenging task. We propose SafeVchat, which is the first solution that achieves satisfactory detection rate by using facial features and skin color model. To harness all the features in the scene, we further developed another system using multiple types of local descriptors along with Bag-of-Visual Word framework. In addition, an investigation of new contour feature in detecting obscene content is presented.

Predictability of refraction following immediate sequential bilateral cataract surgery (ISBCS) performed under general anaesthesia.

PubMed

Guber, Ivo; Rémont, Laurent; Bergin, Ciara

2015-01-01

To evaluate the predictability of refraction following immediate sequential bilateral cataract surgery (ISBCS) performed under general anaesthesia. This is a retrospective review of all ISBCS performed at Kantonsspital Winterthur, Switzerland, between April 2000 and September 2013. The case notes of 250 patients were reviewed. Patients having full refraction reported (110 patients/220 eyes) were included. 210 (95 %) eyes had a straight forward phacoemulsification with posterior chamber intraocular lens implantation, seven eyes had a planned extracapsular cataract extraction (ECCE); three eyes had an intracapsular cataract extraction. Both eyes of 110 patients (64 women, 46 men) with a mean age of 79.0 years, standard deviation (SD) ±11.4 (range 26 to 97 years) were included. Median preoperative best corrected visual acuity (BCVA) was 0.5 LogMAR in the first eye, the interquartile range (IQR) was [0.4, 1.2]; 0.7 LogMAR in the second eye with IQR [0.4, 1.8]. At one month, the median BCVA was 0.2 LogMAR, IQR [0.1, 0.3] in the first eye, median BCVA was 0.1 LogMAR and IQR [0.0, 0.5] in the second eye. There were 3 eyes (3 %) that lost 3 lines or more in BCVA at one month (control vs. pre-operatively). In all three cases, poor visual acuity had been recorded pre-operatively (>1 LogMAR). Achieved refraction was within ±1.0 D of the target in 83 % of eyes. There were only 5 % (n = 6) of cases where if delayed sequential bilateral extraction had been performed could potentially intraocular lens (IOL) choice have been adjusted, in four of these cases, target refraction was within ±1.0 D in the second eye. ISBCS performed under general anaesthesia achieves target refraction in 83 % of eyes after consideration of complications, ocular co-morbidities and systemic restrictions. In the majority of cases where IOL power calculation could be considered, the achieved refraction of the second surgical eye was within ±1.0 D of intended refraction. This undermines the utility of IOL power adjustments in the second surgical eye.

Determination, speciation and distribution of mercury in soil in the surroundings of a former chlor-alkali plant: assessment of sequential extraction procedure and analytical technique

PubMed Central

2013-01-01

Background The paper presents the evaluation of soil contamination with total, water-available, mobile, semi-mobile and non-mobile Hg fractions in the surroundings of a former chlor-alkali plant in connection with several chemical soil characteristics. Principal Component Analysis and Cluster Analysis were used to evaluate the chemical composition variability of soil and factors influencing the fate of Hg in such areas. The sequential extraction EPA 3200-Method and the determination technique based on capacitively coupled microplasma optical emission spectrometry were checked. Results A case study was conducted in the Turda town, Romania. The results revealed a high contamination with Hg in the area of the former chlor-alkali plant and waste landfills, where soils were categorized as hazardous waste. The weight of the Hg fractions decreased in the order semi-mobile > non-mobile > mobile > water leachable. Principal Component Analysis revealed 7 factors describing chemical composition variability of soil, of which 3 attributed to Hg species. Total Hg, semi-mobile, non-mobile and mobile fractions were observed to have a strong influence, while the water leachable fraction a weak influence. The two-dimensional plot of PCs highlighted 3 groups of sites according to the Hg contamination factor. The statistical approach has shown that the Hg fate in soil is dependent on pH, content of organic matter, Ca, Fe, Mn, Cu and SO42- rather than natural components, such as aluminosilicates. Cluster analysis of soil characteristics revealed 3 clusters, one of which including Hg species. Soil contamination with Cu as sulfate and Zn as nitrate was also observed. Conclusions The approach based on speciation and statistical interpretation of data developed in this study could be useful in the investigation of other chlor-alkali contaminated areas. According to the Bland and Altman test the 3-step sequential extraction scheme is suitable for Hg speciation in soil, while the used determination method of Hg is appropriate. PMID:24252185

Vertical Geochemical Variations and Speciation Studies of As, Fe, Mn, Zn, and Cu in the Sediments of the Central Gangetic Basin: Sequential Extraction and Statistical Approach

PubMed Central

Ramanathan, AL.

2018-01-01

A geochemical and speciation study of As, Fe, Mn, Zn, and Cu was performed using sequential extraction and statistical approaches in the core sediments taken at two locations—Rigni Chhapra and Chaube Chhapra—of the central Gangetic basin (India). A gradual increase in the grain size (varying from clay to coarse sands) was observed in both the core profiles up to 30.5 m depth. The concentrations of analyzed elements ranged as follows: 6.9–14.2 mg/kg for As, 13,849–31,088 mg/kg for Fe, 267–711 mg/kg for Mn, 45–164 mg/kg for Cu for Rigni Chhapra while for Chaube Chhapra the range was 7.5–13.2 mg/kg for As, 10,936–37,052 mg/kg for Fe, 267–1052 mg/kg for Mn, 60–198 mg/kg for Zn and 60–108 mg/kg for Cu. Significant amounts (53–95%) of all the fractionated elemental concentrations were bound within the crystal structure of the minerals as a residual fraction. The reducible fraction was the second most dominant fraction for As (7% and 8%), Fe (3%), Mn (20% and 26%), and Cu (7% and 6%) respectively for both the cores. It may be released when aquifers subjected to changing redox conditions. The acid soluble fraction was of most interest because it could quickly mobilize into the water system which formed the third most dominating among all three fractions. Four color code of sediments showed an association with total As concentration and did not show a relation with any fraction of all elements analyzed. The core sediment was observed enriched with As and other elements (Cu, Fe, Mn, and Zn). However, it fell under uncontaminated to moderately contaminate which might exhibit a low risk in prevailing natural conditions. X-ray diffraction analyses indicated the availability of siderite and magnetite minerals in the core sediments in a section of dark grey with micaceous medium sand with organic matter (black). PMID:29360767

Cytotoxicity Evaluation of Two Bis-Acryl Composite Resins Using Human Gingival Fibroblasts.

PubMed

Gonçalves, Fabiano Palmeira; Alves, Gutemberg; Guimarães, Vladi Oliveira; Gallito, Marco Antônio; Oliveira, Felipe; Scelza, Míriam Zaccaro

2016-01-01

Bis-acryl resins are used for temporary dental restorations and have shown advantages over other materials. The aim of this work was to evaluate the in vitro cytotoxicity of two bis-acryl composite resins (Protemp 4 and Luxatemp Star), obtained at 1, 7 and 40 days after mixing the resin components, using a standardized assay employing human primary cells closely related to oral tissues. Human gingival fibroblast cell cultures were exposed for 24 h to either bis-acryl composite resins, polystyrene beads (negative control) and latex (positive control) extracts obtained after incubation by the different periods, at 37 °C under 5% CO2. Cell viability was evaluated using a multiparametric procedure involving sequential assessment (using the same cells) of mitochondrial activity (XTT assay), membrane integrity (neutral red test) and total cell density (crystal violet dye exclusion test). The cells exposed to the resin extracts showed cell viability indexes exceeding 75% after 24 h. Even when cells were exposed to extracts prepared with longer conditioning times, the bis-acryl composite resins showed no significant cytotoxic effects (p>0.05), compared to the control group or in relation to the first 24 h of contact with the products. There were no differences among the results obtained for the bis-acryl composite resins evaluated 24 h, 7 days and 40 days after mixing. It may be concluded that the bis-acryl resins Protemp 4 and Luxatemp Star were cytocompatible with human gingival fibroblasts, suggesting that both materials are suitable for use in contact with human tissues.

Effects of the soil microbial community on mobile proportions and speciation of mercury (Hg) in contaminated soil.

PubMed

Száková, Jiřina; Havlíčková, Jitka; Šípková, Adéla; Gabriel, Jiří; Švec, Karel; Baldrian, Petr; Sysalová, Jiřina; Coufalík, Pavel; Červenka, Rostislav; Zvěřina, Ondřej; Komárek, Josef; Tlustoš, Pavel

2016-01-01

The precise characterization of the behavior of individual microorganisms in the presence of increased mercury contents in soil is necessary for better elucidation of the fate of mercury in the soil environment. In our investigation, resistant bacterial strains isolated from two mercury contaminated soils, represented by Paenibacillus alginolyticus, Burkholderia glathei, Burkholderia sp., and Pseudomonas sp., were used. Two differently contaminated soils (0.5 and 7 mg kg(-1) total mercury) were chosen. Preliminary soil analysis showed the presence of methylmercury and phenylmercury with the higher soil mercury level. Modified rhizobox experiments were performed to assess the ability of mercury accumulating strains to deplete the mobile and mobilizable mercury portions in the soil by modification; microbial agar cultures were used rather than the plant root zone. A sequential extraction procedure was performed to release the following mercury fractions: water soluble, extracted in acidic conditions, bound to humic substances, elemental, and bound to complexes, HgS and residual. Inductively coupled plasma mass spectrometry (ICP-MS) and a single-purpose atomic absorption spectrometer (AMA-254) were applied for mercury determination in the samples and extracts. Gas chromatography coupled to atomic fluorescence spectrometry (GC-AFS) was used for the determination of organomercury compounds. The analysis of the microbial community at the end of the experiment showed a 42% abundance of Paenibacillus sp. followed by Acetivibrio sp., Brevibacillus sp., Cohnella sp., Lysinibacillus sp., and Clostridium sp. not exceeding 2% abundance. The results suggest importance of Paenibacillus sp. in Hg transformation processes. This genus should be tested for potential bioremediation use in further research.

Reducing interaction in simultaneous paired stimulation with CI.

PubMed

Vellinga, Dirk; Bruijn, Saskia; Briaire, Jeroen J; Kalkman, Randy K; Frijns, Johan H M

2017-01-01

In this study simultaneous paired stimulation of electrodes in cochlear implants is investigated by psychophysical experiments in 8 post-lingually deaf subjects (and one extra subject who only participated in part of the experiments). Simultaneous and sequential monopolar stimulation modes are used as references and are compared to channel interaction compensation, partial tripolar stimulation and a novel sequential stimulation strategy named phased array compensation. Psychophysical experiments are performed to investigate both the loudness integration during paired stimulation at the main electrodes as well as the interaction with the electrode contact located halfway between the stimulating pair. The study shows that simultaneous monopolar stimulation has more loudness integration on the main electrodes and more interaction in between the electrodes than sequential stimulation. Channel interaction compensation works to reduce the loudness integration at the main electrodes, but does not reduce the interaction in between the electrodes caused by paired stimulation. Partial tripolar stimulation uses much more current to reach the needed loudness, but shows the same interaction in between the electrodes as sequential monopolar stimulation. In phased array compensation we have used the individual impedance matrix of each subject to calculate the current needed on each electrode to exactly match the stimulation voltage along the array to that of sequential stimulation. The results show that the interaction in between the electrodes is the same as monopolar stimulation. The strategy uses less current than partial tripolar stimulation, but more than monopolar stimulation. In conclusion, the paper shows that paired stimulation is possible if the interaction is compensated.

Larvicidal, pupicidal, repellent and adulticidal activity of Citrus sinensis orange peel extract against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae).

PubMed

Murugan, Kadarkarai; Mahesh Kumar, Palanisamy; Kovendan, Kalimuthu; Amerasan, Duraisamy; Subrmaniam, Jayapal; Hwang, Jiang-Shiou

2012-10-01

Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikunguniya fever, West Nile virus and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. The present study explored the effects of orange peel ethanol extract of Citrus sinensis on larvicidal, pupicidal, repellent and adulticidal activity against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. The orange peel material was shade dried at room temperature and powdered coarsely. From orange peel, 300 g powdered was macerated with 1 L of ethanol sequentially for a period of 72 h each and filtered. The yields of the orange peel ethanol crude extract of C. sinensis 13.86 g, respectively. The extracts were concentrated at reduced temperature on a rotary vacuum evaporator and stored at a temperature of 4 °C. The larvicidal, pupicidal and adult mortality was observed after 24 h of exposure; no mortality was observed in the control group. For C. sinensis, the median lethal concentration values (LC(50)) observed for the larvicidal and pupicidal activities against mosquito vector species A. stephensi first to fourth larval instars and pupae were 182.24, 227.93, 291.69, 398.00 and 490.84 ppm; A. aegypti values were 92.27, 106.60, 204.87, 264.26, 342.45, 436.93 and 497.41 ppm; and C. quinquefasciatus values were 244.70, 324.04, 385.32, 452.78 and 530.97 ppm, respectively. The results of maximum repellent activity were observed at 450 ppm in ethanol extracts of C. sinensis and the mean complete protection time ranged from 150 to 180 min was tested. The ethanol extract of C. sinensis showed 100% repellency in 150 min and showed complete protection in 90 min at 350 ppm against A. stephensi, A. aegypti and C. quinquefasciatus, respectively. The adult mortality was found in ethanol extract of C. sinensis with the LC(50) and LC(90) values of 272.19 and 457.14 ppm, A. stephensi; 289.62 and 494.88 ppm, A. aegypti; and 320.38 and 524.57 ppm, respectively. These results suggest that the orange peel extracts of C. sinensis have the potential to be used as an ideal eco-friendly approach for the control of the vector control programmes.

Spatial versus sequential correlations for random access coding

NASA Astrophysics Data System (ADS)

Tavakoli, Armin; Marques, Breno; Pawłowski, Marcin; Bourennane, Mohamed

2016-03-01

Random access codes are important for a wide range of applications in quantum information. However, their implementation with quantum theory can be made in two very different ways: (i) by distributing data with strong spatial correlations violating a Bell inequality or (ii) using quantum communication channels to create stronger-than-classical sequential correlations between state preparation and measurement outcome. Here we study this duality of the quantum realization. We present a family of Bell inequalities tailored to the task at hand and study their quantum violations. Remarkably, we show that the use of spatial and sequential quantum correlations imposes different limitations on the performance of quantum random access codes: Sequential correlations can outperform spatial correlations. We discuss the physics behind the observed discrepancy between spatial and sequential quantum correlations.

Distortion product otoacoustic emissions: comparison of sequential vs. simultaneous presentation of primary tones.

PubMed

Kumar, U Ajith; Maruthy, Sandeep; Chandrakant, Vishwakarma

2009-03-01

Distortion product otoacoustic emissions are one form of evoked otoacoustic emissions. DPOAEs provide the frequency specific information about the hearing status in mid and high frequency regions. But in most screening protocols TEOAEs are preferred as it requires less time compared to DPOAE. This is because, in DPOAE each stimulus is presented one after the other and responses are analyzed. Grason and Stadler Incorporation 60 (GSI-60) offer simultaneous presentation of four sets of primary tones at a time and checks for the DPOAE. In this mode of presentation, all the pairs are presented at a time and following that response is extracted separately whereas, in sequential mode primaries are presented in orderly fashion one after the other. In this article simultaneous and sequential protocols were used to compare the Distortion product otoacoustic emission amplitude, noise floor and administration time in individuals with normal hearing and mild sensori-neural (SN) hearing loss. In simultaneous protocols four sets of primary tones (i.e. 8 tones) were presented together whereas, in sequential presentation mode one set of primary tones was presented each time. Simultaneous protocol was completed in less than half the time required for the completion of sequential protocol. Two techniques yielded similar results at frequencies above 1000 Hz only in normal hearing group. In SN hearing loss group simultaneous presentation yielded signifi cantly higher noise floors and distortion product amplitudes. This result challenges the use of simultaneous presentation technique in neonatal hearing screening programmes and on other pathologies. This discrepancy between two protocols may be due to some changes in biomechanical process in the cochlear and/or due to higher distortion/noise produced by the system during the simultaneous presentation mode.

Sequential Tests of Multiple Hypotheses Controlling Type I and II Familywise Error Rates

PubMed Central

Bartroff, Jay; Song, Jinlin

2014-01-01

This paper addresses the following general scenario: A scientist wishes to perform a battery of experiments, each generating a sequential stream of data, to investigate some phenomenon. The scientist would like to control the overall error rate in order to draw statistically-valid conclusions from each experiment, while being as efficient as possible. The between-stream data may differ in distribution and dimension but also may be highly correlated, even duplicated exactly in some cases. Treating each experiment as a hypothesis test and adopting the familywise error rate (FWER) metric, we give a procedure that sequentially tests each hypothesis while controlling both the type I and II FWERs regardless of the between-stream correlation, and only requires arbitrary sequential test statistics that control the error rates for a given stream in isolation. The proposed procedure, which we call the sequential Holm procedure because of its inspiration from Holm’s (1979) seminal fixed-sample procedure, shows simultaneous savings in expected sample size and less conservative error control relative to fixed sample, sequential Bonferroni, and other recently proposed sequential procedures in a simulation study. PMID:25092948

Sequential injection spectrophotometric determination of oxybenzone in lipsticks.

PubMed

Salvador, A; Chisvert, A; Camarasa, A; Pascual-Martí, M C; March, J G

2001-08-01

A sequential injection (SI) procedure for the spectrophotometric determination of oxybenzone in lipsticks is reported. The colorimetric reaction between nickel and oxybenzone was used. SI parameters such as sample solution volume, reagent solution volume, propulsion flow rate and reaction coil length were studied. The limit of detection was 3 microg ml(-1). The sensitivity was 0.0108+/-0.0002 ml microg(-1). The relative standard deviations of the results were between 6 and 12%. The real concentrations of samples and the values obtained by HPLC were comparable. Microwave sample pre-treatment allowed the extraction of oxybenzone with ethanol, thus avoiding the use of toxic organic solvents. Ethanol was also used as carrier in the SI system. Seventy-two injections per hour can be performed, which means a sample frequency of 24 h(-1) if three replicates are measured for each sample.

Patterns and Sequences: Interactive Exploration of Clickstreams to Understand Common Visitor Paths.

PubMed

Liu, Zhicheng; Wang, Yang; Dontcheva, Mira; Hoffman, Matthew; Walker, Seth; Wilson, Alan

2017-01-01

Modern web clickstream data consists of long, high-dimensional sequences of multivariate events, making it difficult to analyze. Following the overarching principle that the visual interface should provide information about the dataset at multiple levels of granularity and allow users to easily navigate across these levels, we identify four levels of granularity in clickstream analysis: patterns, segments, sequences and events. We present an analytic pipeline consisting of three stages: pattern mining, pattern pruning and coordinated exploration between patterns and sequences. Based on this approach, we discuss properties of maximal sequential patterns, propose methods to reduce the number of patterns and describe design considerations for visualizing the extracted sequential patterns and the corresponding raw sequences. We demonstrate the viability of our approach through an analysis scenario and discuss the strengths and limitations of the methods based on user feedback.

Research on aviation unsafe incidents classification with improved TF-IDF algorithm

NASA Astrophysics Data System (ADS)

Wang, Yanhua; Zhang, Zhiyuan; Huo, Weigang

2016-05-01

The text content of Aviation Safety Confidential Reports contains a large number of valuable information. Term frequency-inverse document frequency algorithm is commonly used in text analysis, but it does not take into account the sequential relationship of the words in the text and its role in semantic expression. According to the seven category labels of civil aviation unsafe incidents, aiming at solving the problems of TF-IDF algorithm, this paper improved TF-IDF algorithm based on co-occurrence network; established feature words extraction and words sequential relations for classified incidents. Aviation domain lexicon was used to improve the accuracy rate of classification. Feature words network model was designed for multi-documents unsafe incidents classification, and it was used in the experiment. Finally, the classification accuracy of improved algorithm was verified by the experiments.

Image segmentation for biomedical applications based on alternating sequential filtering and watershed transformation

NASA Astrophysics Data System (ADS)

Gorpas, D.; Yova, D.

2009-07-01

One of the major challenges in biomedical imaging is the extraction of quantified information from the acquired images. Light and tissue interaction leads to the acquisition of images that present inconsistent intensity profiles and thus the accurate identification of the regions of interest is a rather complicated process. On the other hand, the complex geometries and the tangent objects that very often are present in the acquired images, lead to either false detections or to the merging, shrinkage or expansion of the regions of interest. In this paper an algorithm, which is based on alternating sequential filtering and watershed transformation, is proposed for the segmentation of biomedical images. This algorithm has been tested over two applications, each one based on different acquisition system, and the results illustrate its accuracy in segmenting the regions of interest.

IgG and IgM anti-snRNP reactivity in sequentially obtained serum samples from patients with connective tissue diseases.

PubMed Central

Nyman, U; Lundberg, I; Hedfors, E; Wahren, M; Pettersson, I

1992-01-01

Sequentially obtained serum samples from 30 patients with connective tissue disease positive for antibody to ribonucleoprotein (RNP) were examined to determine the specificities of IgG and IgM antibodies to snRNP during the disease course using immunoblotting of nuclear extracts. The antibody patterns were correlated with disease activity. The patterns of antibody to snRNP of individual patients were mainly stable during the study but changes in levels of antibody to snRNP were seen corresponding to changes in clinical activity. These results indicate that increased reactivity of serum IgM antibodies against the B/B' proteins seems to precede a clinically evident exacerbation of disease whereas IgG antibody reactivity to the 70 K protein peaks at the time of a disease flare. Images PMID:1485812

Antioxidant and cytotoxic activities of three species of tropical seaweeds.

PubMed

Chia, Yin Yin; Kanthimathi, M S; Khoo, Kong Soo; Rajarajeswaran, Jayakumar; Cheng, Hwee Ming; Yap, Wai Sum

2015-09-29

Three species of seaweeds (Padina tetrastromatica, Caulerpa racemosa and Turbinaria ornata) are widely consumed by Asians as nutraceutical food due to their antioxidant properties. Studies have shown that these seaweeds exhibit bioactivities which include antimicrobial, antiviral, anti-hypertensive and anticoagulant activities. However, investigations into the mechanisms of action pertaining to the cytotoxic activity of the seaweeds are limited. The aim of this study was to determine the antioxidant and cytotoxic activities of whole extracts of P. tetrastromatica, C. racemosa and T. ornata, including the cellular events leading to the apoptotic cell death of the extract treated-MCF-7 cells. Bioassay guided fractionation was carried out and the compounds identified. Powdered samples were sequentially extracted for 24 h. Their antioxidant activities were assessed by the DPPH radical, superoxide, nitric oxide and hydroxyl radical scavenging assays. The cytotoxic activity of the extract-treated MCF-7cells was assessed using the MTT assay. The most potent fraction was subjected to bioassay guided fractionation with column chromatography. All the fractions were tested for cytotoxic activity, caspase activity and effect on DNA fragmentation. All three seaweeds showed potent radical scavenging activities in the various assays. The activity of the cellular antioxidant enzymes, superoxide dismutase, catalase and glutathione reductase, in MCF-7 cells, decreased in a time-dependent manner. The partially purified fractions exhibited higher cytotoxic activity, as assessed by the MTT assay, than the whole extracts in the breast adenocarcinoma cell line, MCF-7. LC-MS analysis revealed the presence of bioactive alkaloids such as camptothecin, lycodine and pesudopelletierine. Based on the results obtained, all three seaweeds are rich sources of enzymatic and non-enzymatic antioxidants which could contribute to their reported medicinal benefits.

[Macromolecular aromatic network characteristics of Chinese power coal analyzed by synchronous fluorescence and X-ray diffraction].

PubMed

Ye, Cui-Ping; Feng, Jie; Li, Wen-Ying

2012-07-01

Coal structure, especially the macromolecular aromatic skeleton structure, has a strong influence on coke reactivity and coal gasification, so it is the key to grasp the macromolecular aromatic skeleton coal structure for getting the reasonable high efficiency utilization of coal. However, it is difficult to acquire their information due to the complex compositions and structure of coal. It has been found that the macromolecular aromatic network coal structure would be most isolated if small molecular of coal was first extracted. Then the macromolecular aromatic skeleton coal structure would be clearly analyzed by instruments, such as X-ray diffraction (XRD), fluorescence spectroscopy with synchronous mode (Syn-F), Gel permeation chromatography (GPC) etc. Based on the previous results, according to the stepwise fractional liquid extraction, two Chinese typical power coals, PS and HDG, were extracted by silica gel as stationary phase and acetonitrile, tetrahydrofuran (THF), pyridine and 1-methyl-2-pyrollidinone (NMP) as a solvent group for sequential elution. GPC, Syn-F and XRD were applied to investigate molecular mass distribution, condensed aromatic structure and crystal characteristics. The results showed that the size of aromatic layers (La) is small (3-3.95 nm) and the stacking heights (Lc) are 0.8-1.2 nm. The molecular mass distribution of the macromolecular aromatic network structure is between 400 and 1 130 amu, with condensed aromatic numbers of 3-7 in the structure units.

Membrane-associated mucins in normal human conjunctiva.

PubMed

Berry, M; Ellingham, R B; Corfield, A P

2000-02-01

To examine the presence of specific membrane-associated mucins in normal human conjunctiva. Glycoconjugates were extracted from membranes with two detergents: octylglucoside and Triton X114. Mucins were separated by cesium chloride density gradient centrifugation. Size was assessed by gel filtration on Sepharose CL2B and charge by ion-exchange chromatography on MonoQ. Cross reaction with antibodies against mucin gene products was assessed in blots of electrophoresis gels. Extraction of total tissue membranes yielded material with a buoyant density typical of mucins. Gel filtration showed material reacting with antimucin antibodies in a range of molecular sizes. Agarose electrophoresis confirmed the presence of MUC1 and MUC4 and the absence of MUC2 or MUC5AC. Isolation of membrane mucins by sequential, exhaustive extraction with octylglucoside followed by Triton X114 suggested the existence of mucins in different membrane environments. Reagents to carbohydrate epitopes revealed high mobility material, comigrating with MUC1 and MUC4. Low mobility membrane-bound mucins did not cross-react with any antibodies to mucin genes known to be expressed in human conjunctiva. Membrane-associated mucins are distinct from secreted mucins in normal human conjunctiva. MUC1 and MUC4 mature products decorate the membranes of conjunctival epithelial cells. Their segregation between octyl glucoside and the detergent and aqueous phases of Triton X114 suggests a variety of membrane anchoring modes.

Speciation and distribution characteristics of heavy metals and pollution assessments in the sediments of Nashina Lake, Heilongjiang, China.

PubMed

Li, Miao; Zang, Shuying; Xiao, Haifeng; Wu, Changshan

2014-05-01

Sediment core samples from Nashina Lake, Heilongjiang, China were collected using a gravity sampler. The cores were sliced horizontally at 1 cm each to determine the particle size, total concentrations and speciation of Cd, Cr, Cu, Mn, Ni, Pb, and Zn. Total concentrations of heavy metals were extracted using an acid mixture (containing hydro fluoric acid, nitric acid, and sulphuric acid) and analyzed using an inductively coupled plasma spectrometry. A sequential extraction procedure was employed to separate chemical species. Analysis of results indicate that the concentrations of heavy metals in the sediments of Nashina Lake in descending order are Mn, Cr, Zn, Pb, Ni, Cu, and Cd. The ratios of the average concentrations of four heavy metals (e.g.Cr, Cu, Ni, Zn) to their background values were >1; and those of Mn, Cd, and Pb were >1. Moreover, some toxic metals were mainly distributed in bioavailable fractions. For instance, both Cd and Mn were typically found in Acid-extractable species or Fe-Mn oxide species, and thus can be easily remobilized and enter the food chain. Finally, the analysis of geo-accumulation index showed that anthropogenic pollution levels of Cr, Cu, Mn, Ni, Zn were low, but those of Pb and Cd were at the moderate level. As both Pb and Cd are toxic metals, it is highly necessary to prohibit their transformation and accumulation in the sediments.