Evaluation of Superparamagnetic Silica Nanoparticles for Extraction of Triazines in Magnetic in-Tube Solid Phase Microextraction Coupled to Capillary Liquid Chromatography

PubMed Central

González-Fuenzalida, R. A.; Moliner-Martínez, Y.; Prima-Garcia, Helena; Ribera, Antonio; Campins-Falcó, P.; Zaragozá, Ramon J.

2014-01-01

The use of magnetic nanomaterials for analytical applications has increased in the recent years. In particular, magnetic nanomaterials have shown great potential as adsorbent phase in several extraction procedures due to the significant advantages over the conventional methods. In the present work, the influence of magnetic forces over the extraction efficiency of triazines using superparamagnetic silica nanoparticles (NPs) in magnetic in tube solid phase microextraction (Magnetic-IT-SPME) coupled to CapLC has been evaluated. Atrazine, terbutylazine and simazine has been selected as target analytes. The superparamagnetic silica nanomaterial (SiO2-Fe3O4) deposited onto the surface of a capillary column gave rise to a magnetic extraction phase for IT-SPME that provided a enhancemment of the extraction efficiency for triazines. This improvement is based on two phenomena, the superparamegnetic behavior of Fe3O4 NPs and the diamagnetic repulsions that take place in a microfluidic device such a capillary column. A systematic study of analytes adsorption and desorption was conducted as function of the magnetic field and the relationship with triazines magnetic susceptibility. The positive influence of magnetism on the extraction procedure was demonstrated. The analytical characteristics of the optimized procedure were established and the method was applied to the determination of the target analytes in water samples with satisfactory results. When coupling Magnetic-IT-SPME with CapLC, improved adsorption efficiencies (60%–63%) were achieved compared with conventional adsorption materials (0.8%–3%). PMID:28344221

Multiplex polymerase chain reaction detection of black-pigmented bacteria in infections of endodontic origin.

PubMed

Seol, Jung-Hwan; Cho, Byung-Hoon; Chung, Chong-Pyoung; Bae, Kwang-Shik

2006-02-01

The purpose of this study was to detect the presence of Porphyromonas endodontalis, P. gingivalis, Prevotella intermedia, P. nigrescens, and P. tannerae from clinical samples using multiplex polymerase chain reactions (PCR). Two different multiplex PCR protocols were used (one for the two Porphyromonas species and the other for the three Prevotella species), each one using a primer pair specific for each target species. The results were compared to those of the conventional culture procedures. Microbial samples were taken aseptically from 40 infected root canals and abscesses from patients. Samples were cultured in an anaerobic condition for conventional identification using a Rapid ID 32 A kit. Multiplex PCR was processed using the DNA extracted from each sample. At least one of the five species of black-pigmented bacteria (BPB) were detected in 65% (26 of 40) of the samples using multiplex PCR, and in 15% (6 of 40) using the conventional culture procedures. Multiplex PCR was more rapid, sensitive, specific, and effective in detecting BPB than the conventional culture procedures.

Sensitive determination of total particulate phosphorus and particulate inorganic phosphorus in seawater using liquid waveguide spectrophotometry.

PubMed

Ehama, Makoto; Hashihama, Fuminori; Kinouchi, Shinko; Kanda, Jota; Saito, Hiroaki

2016-06-01

Determining the total particulate phosphorus (TPP) and particulate inorganic phosphorus (PIP) in oligotrophic oceanic water generally requires the filtration of a large amount of water sample. This paper describes methods that require small filtration volumes for determining the TPP and PIP concentrations. The methods were devised by validating or improving conventional sample processing and by applying highly sensitive liquid waveguide spectrophotometry to the measurements of oxidized or acid-extracted phosphate from TPP and PIP, respectively. The oxidation of TPP was performed by a chemical wet oxidation method using 3% potassium persulfate. The acid extraction of PIP was initially carried out based on the conventional extraction methodology, which requires 1M HCl, followed by the procedure for decreasing acidity. While the conventional procedure for acid removal requires a ten-fold dilution of the 1M HCl extract with purified water, the improved procedure proposed in this study uses 8M NaOH solution for neutralizing 1M HCl extract in order to reduce the dilution effect. An experiment for comparing the absorbances of the phosphate standard dissolved in 0.1M HCl and of that dissolved in a neutralized solution [1M HCl: 8M NaOH=8:1 (v:v)] exhibited a higher absorbance in the neutralized solution. This indicated that the improved procedure completely removed the acid effect, which reduces the sensitivity of the phosphate measurement. Application to an ultraoligotrophic water sample showed that the TPP concentration in a 1075mL-filtered sample was 8.4nM with a coefficient of variation (CV) of 4.3% and the PIP concentration in a 2300mL-filtered sample was 1.3nM with a CV of 6.1%. Based on the detection limit (3nM) of the sensitive phosphate measurement and the ambient TPP and PIP concentrations of the ultraoligotrophic water, the minimum filtration volumes required for the detection of TPP and PIP were estimated to be 15 and 52mL, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

New procedure for extraction of algal lipids from wet biomass: a green clean and scalable process.

PubMed

Dejoye Tanzi, Celine; Abert Vian, Maryline; Chemat, Farid

2013-04-01

A new procedure, called Simultaneous Distillation and Extraction Process (SDEP), for lipid extraction from wet microalgae (Nannochloropsis oculata and Dunaliella salina) was reported. This method does not require a pre-drying of the biomass and employs alternative solvents such as d-limonene, α-pinene and p-cymene. This procedure has been compared with Soxhlet extraction (Sox) and Bligh & Dyer method (B&D). For N. oculata, results showed that SDEP-cymene provided similar lipid yields to B&D (21.45% and 23.78%), while SDEP-limonene and pinene provided lower yields (18.73% and 18.75% respectively). For D. salina, SDEP-pinene provided the maximum lipid yield (3.29%) compared to the other solvents, which is quite close to B&D result (4.03%). No significant differences in terms of distribution of lipid classes and fatty acid composition have been obtained for different techniques. Evaluation of energy consumption indicates a substantial saving in the extraction cost by SDEP compared to the conventional extraction technique, Soxhlet. Copyright © 2013 Elsevier Ltd. All rights reserved.

Seasonal Shifts in the Biochemical Compoments of the Light Fraction, Particulate Organic Matter, and Two Humic Acid Fractions in An Iowa Soil

USDA-ARS?s Scientific Manuscript database

Soil organic matter is conventionally extracted through either physical or chemical means. The benefits of integrating both approaches into one fractionation procedure were evaluated on an Iowa corn-soybean soil used for a cover crop study. The light fraction was first extracted from the 0-5 cm soil...

Use of different sample temperatures in a single extraction procedure for the screening of the aroma profile of plant matrices by headspace solid-phase microextraction.

PubMed

Martendal, Edmar; de Souza Silveira, Cristine Durante; Nardini, Giuliana Stael; Carasek, Eduardo

2011-06-17

This study proposes a new approach to the optimization of the extraction of the volatile fraction of plant matrices using the headspace solid-phase microextraction (HS-SPME) technique. The optimization focused on the extraction time and temperature using a CAR/DVB/PDMS 50/30 μm SPME fiber and 100mg of a mixture of plants as the sample in a 15-mL vial. The extraction time (10-60 min) and temperature (5-60 °C) were optimized by means of a central composite design. The chromatogram was divided into four groups of peaks based on the elution temperature to provide a better understanding of the influence of the extraction parameters on the extraction efficiency considering compounds with different volatilities/polarities. In view of the different optimum extraction time and temperature conditions obtained for each group, a new approach based on the use of two extraction temperatures in the same procedure is proposed. The optimum conditions were achieved by extracting for 30 min with a sample temperature of 60 °C followed by a further 15 min at 5 °C. The proposed method was compared with the optimized conventional method based on a single extraction temperature (45 min of extraction at 50 °C) by submitting five samples to both procedures. The proposed method led to better results in all cases, considering as the response both peak area and the number of identified peaks. The newly proposed optimization approach provided an excellent alternative procedure to extract analytes with quite different volatilities in the same procedure. Copyright © 2011 Elsevier B.V. All rights reserved.

A comparative study of conventional and supercritical fluid extraction methods for the recovery of secondary metabolites from Syzygium campanulatum Korth.

PubMed

Memon, Abdul Hakeem; Hamil, Mohammad Shahrul Ridzuan; Laghari, Madeeha; Rithwan, Fahim; Zhari, Salman; Saeed, Mohammed Ali Ahmed; Ismail, Zhari; Majid, Amin Malik Shah Abdul

2016-09-01

Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites (especially flavanones, chalcone, and triterpenoids). In our present study, three conventional solvent extraction (CSE) techniques and supercritical fluid extraction (SFE) techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques (maceration, soxhletion, and reflux). An enriched extract of five secondary metabolites was collected using n-hexane:methanol (1:1) soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery (25.5%‒84.9%) of selected secondary metabolites as compared to the CSE techniques (0.92%‒66.00%).

A comparative study of conventional and supercritical fluid extraction methods for the recovery of secondary metabolites from Syzygium campanulatum Korth#

PubMed Central

Memon, Abdul Hakeem; Hamil, Mohammad Shahrul Ridzuan; Laghari, Madeeha; Rithwan, Fahim; Zhari, Salman; Saeed, Mohammed Ali Ahmed; Ismail, Zhari; Majid, Amin Malik Shah Abdul

2016-01-01

Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites (especially flavanones, chalcone, and triterpenoids). In our present study, three conventional solvent extraction (CSE) techniques and supercritical fluid extraction (SFE) techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques (maceration, soxhletion, and reflux). An enriched extract of five secondary metabolites was collected using n-hexane:methanol (1:1) soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery (25.5%‒84.9%) of selected secondary metabolites as compared to the CSE techniques (0.92%‒66.00%). PMID:27604860

Antioxidant potential of mulberry and non-mulberry silk sericin and its implications in biomedicine.

PubMed

Kumar, Jadi Praveen; Mandal, Biman B

2017-07-01

Sericin, a principal constituent of silk, is widely used in various biomedical applications. In addition, conferring protection against free radicals and oxidative damage add more value to its therapeutic potential. However, the antioxidant (AO) properties of silk sericin (SS) remains contingent on extraction procedures. In the present study, we have evaluated the effect of different extraction methods (conventional, autoclaving, urea, alkali and acid-degradation) on AO properties of SS from three Indian silk varieties [Antheraea assamensis (AA), Philosamia ricini (PR) and Bombyx mori (BM)]. The physico-chemical characterization studies revealed that the molecular weight of SS isolates of each method ranged from 10 to 220kDa along with varied protein structural biochemistry. SS extracts using urea-degradation (BM, PR and AA), conventional method and alkali-degradation (BM) displayed high percentage of β-sheets, random coils and turns. Acid-degraded SS (PR, followed by AA and BM) showed the highest total flavonoid content while conventional method (PR), autoclaving (AA) and alkali-degradation (BM) displayed lowest flavonoid levels. Interestingly, SS extracted by autoclaving (BM and AA), acid-degradation (PR), conventional and alkali-degradation (BM, AA and PR) methods exhibited 50% reduction of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical. Moreover, the efficacy of antioxidant potential of SS extracted by different methods was found to be in the order of "alkali>autoclaving>conventional" as demonstrated in L929 cells. Correspondingly, the anti-lipid peroxidation activity of SS extracted by alkali method (AA, BM and PR) further confirmed better AO properties amid others. Thus, the present study demonstrates that the extraction methods may significantly affect AO activity of SS which might be of importance for potential cosmetic applications. Copyright © 2017 Elsevier Inc. All rights reserved.

Microwave-assisted extraction and mild saponification for determination of organochlorine pesticides in oyster samples.

PubMed

Carro, N; García, I; Ignacio, M-C; Llompart, M; Yebra, M-C; Mouteira, A

2002-10-01

A sample-preparation procedure (extraction and saponification) using microwave energy is proposed for determination of organochlorine pesticides in oyster samples. A Plackett-Burman factorial design has been used to optimize the microwave-assisted extraction and mild saponification on a freeze dried sample spiked with a mixture of aldrin, endrin, dieldrin, heptachlor, heptachorepoxide, isodrin, transnonachlor, p, p'-DDE, and p, p'-DDD. Six variables: solvent volume, extraction time, extraction temperature, amount of acetone (%) in the extractant solvent, amount of sample, and volume of NaOH solution were considered in the optimization process. The results show that the amount of sample is statistically significant for dieldrin, aldrin, p, p'-DDE, heptachlor, and transnonachlor and solvent volume for dieldrin, aldrin, and p, p'-DDE. The volume of NaOH solution is statistically significant for aldrin and p, p'-DDE only. Extraction temperature and extraction time seem to be the main factors determining the efficiency of extraction process for isodrin and p, p'-DDE, respectively. The optimized procedure was compared with conventional Soxhlet extraction.

Antimicrobial and Antibiofilm Activities of Citrus Water-Extracts Obtained by Microwave-Assisted and Conventional Methods.

PubMed

Caputo, Leonardo; Quintieri, Laura; Cavalluzzi, Maria Maddalena; Lentini, Giovanni; Habtemariam, Solomon

2018-06-17

Citrus pomace is a huge agro-food industrial waste mostly composed of peels and traditionally used as compost or animal feed. Owing to its high content of compounds beneficial to humans (e.g., flavonoids, phenol-like acids, and terpenoids), citrus waste is increasingly used to produce valuable supplements, fragrance, or antimicrobials. However, such processes require sustainable and efficient extraction strategies by solvent-free techniques for environmentally-friendly good practices. In this work, we evaluated the antimicrobial and antibiofilm activity of water extracts of three citrus peels (orange, lemon, and citron) against ten different sanitary relevant bacteria. Both conventional extraction methods using hot water (HWE) and microwave-assisted extraction (MAE) were used. Even though no extract fully inhibited the growth of the target bacteria, these latter (mostly pseudomonads) showed a significant reduction in biofilm biomass. The most active extracts were obtained from orange and lemon peel by using MAE at 100 °C for 8 min. These results showed that citrus peel water infusions by MAE may reduce biofilm formation possibly enhancing the susceptibility of sanitary-related bacteria to disinfection procedures.

A novel automated device for rapid nucleic acid extraction utilizing a zigzag motion of magnetic silica beads.

PubMed

Yamaguchi, Akemi; Matsuda, Kazuyuki; Uehara, Masayuki; Honda, Takayuki; Saito, Yasunori

2016-02-04

We report a novel automated device for nucleic acid extraction, which consists of a mechanical control system and a disposable cassette. The cassette is composed of a bottle, a capillary tube, and a chamber. After sample injection in the bottle, the sample is lysed, and nucleic acids are adsorbed on the surface of magnetic silica beads. These magnetic beads are transported and are vibrated through the washing reagents in the capillary tube under the control of the mechanical control system, and thus, the nucleic acid is purified without centrifugation. The purified nucleic acid is automatically extracted in 3 min for the polymerase chain reaction (PCR). The nucleic acid extraction is dependent on the transport speed and the vibration frequency of the magnetic beads, and optimizing these two parameters provided better PCR efficiency than the conventional manual procedure. There was no difference between the detection limits of our novel device and that of the conventional manual procedure. We have already developed the droplet-PCR machine, which can amplify and detect specific nucleic acids rapidly and automatically. Connecting the droplet-PCR machine to our novel automated extraction device enables PCR analysis within 15 min, and this system can be made available as a point-of-care testing in clinics as well as general hospitals. Copyright © 2015 Elsevier B.V. All rights reserved.

Application of dual-cloud point extraction for the trace levels of copper in serum of different viral hepatitis patients by flame atomic absorption spectrometry: A multivariate study

NASA Astrophysics Data System (ADS)

Arain, Salma Aslam; Kazi, Tasneem G.; Afridi, Hassan Imran; Abbasi, Abdul Rasool; Panhwar, Abdul Haleem; Naeemullah; Shanker, Bhawani; Arain, Mohammad Balal

2014-12-01

An efficient, innovative preconcentration method, dual-cloud point extraction (d-CPE) has been developed for the extraction and preconcentration of copper (Cu2+) in serum samples of different viral hepatitis patients prior to couple with flame atomic absorption spectrometry (FAAS). The d-CPE procedure was based on forming complexes of elemental ions with complexing reagent 1-(2-pyridylazo)-2-naphthol (PAN), and subsequent entrapping the complexes in nonionic surfactant (Triton X-114). Then the surfactant rich phase containing the metal complexes was treated with aqueous nitric acid solution, and metal ions were back extracted into the aqueous phase, as second cloud point extraction stage, and finally determined by flame atomic absorption spectrometry using conventional nebulization. The multivariate strategy was applied to estimate the optimum values of experimental variables for the recovery of Cu2+ using d-CPE. In optimum experimental conditions, the limit of detection and the enrichment factor were 0.046 μg L-1 and 78, respectively. The validity and accuracy of proposed method were checked by analysis of Cu2+ in certified sample of serum (CRM) by d-CPE and conventional CPE procedure on same CRM. The proposed method was successfully applied to the determination of Cu2+ in serum samples of different viral hepatitis patients and healthy controls.

Convenient Detection of the Citrus Greening (Huanglongbing) Bacterium ‘Candidatus Liberibacter asiaticus’ by Direct PCR from the Midrib Extract

PubMed Central

Fujikawa, Takashi; Miyata, Shin-Ichi; Iwanami, Toru

2013-01-01

A phloem-limited bacterium, ‘Candidatus Liberibacter asiaticus’ (Las) is a major pathogen of citrus greening (huanglongbing), one of the most destructive citrus diseases worldwide. The rapid identification and culling of infected trees and budwoods in quarantine are the most important control measures. DNA amplification including conventional polymerase chain reaction (PCR) has commonly been used for rapid detection and identification. However, long and laborious procedures for DNA extraction have greatly reduced the applicability of this method. In this study, we found that the Las bacterial cells in the midribs of infected leaves were extracted rapidly and easily by pulverization and centrifugation with mini homogenization tubes. We also found that the Las bacterial cells in the midrib extract were suitable for highly sensitive direct PCR. The performance of direct PCR using this extraction method was not inferior to that of conventional PCR. Thus, the direct PCR method described herein is characterized by its simplicity, sensitivity, and robustness, and is applicable to quarantine testing. PMID:23437295

Metal speciation of environmental samples using SPE and SFC-AED analysis

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

Mitchell, S.C.; Burford, M.D.; Robson, M.

1995-12-31

Due to growing public concern over heavy metals in the environment, soil, water and air particulate samples azre now routinely screened for their metal content. Conventional metal analysis typically involves acid digestion extraction and results in the generation of large aqueous and organic solvent waste. This harsh extraction process is usually used to obtain the total metal content of the sample, the extract being analysed by atomic emission or absorption spectroscoply techniques. A more selective method of metal extraction has been investigated which uses a supercritical fluid modified with a complexing agent. The relatively mild extraction method enables both organometallicmore » and inorganic metal species to be recovered intact. The various components from the supercritical fluid extract can be chromatographically separated using supercritical fluid chromatography (SFC) and positive identification of the metals achieved using atomic emission detection (AED). The aim of the study is to develop an analytical extraction procedure which enables a rapid, sensitive and quantitative analysis of metals in environmental samples, using just one extraction (eg SFE) and one analysis (eg SFC-AED) procedure.« less

Comparison of Piezosurgery and Conventional Rotary Instruments for Removal of Impacted Mandibular Third Molars: A Randomized Controlled Clinical and Radiographic Trial

PubMed Central

Shokry, Mohamed; Aboelsaad, Nayer

2016-01-01

The purpose of this study was to test the effect of the surgical removal of impacted mandibular third molars using piezosurgery versus the conventional surgical technique on postoperative sequelae and bone healing. Material and Methods. This study was carried out as a randomized controlled clinical trial: split mouth design. Twenty patients with bilateral mandibular third molar mesioangular impaction class II position B indicated for surgical extraction were treated randomly using either the piezosurgery or the conventional bur technique on each site. Duration of the procedure, postoperative edema, trismus, pain, healing, and bone density and quantity were evaluated up to 6 months postoperatively. Results. Test and control sites were compared using paired t-test. There was statistical significance in reduction of pain and swelling in test sites, where the time of the procedure was statistically increased in test site. For bone quantity and quality, statistical difference was found where test site showed better results. Conclusion. Piezosurgery technique improves quality of patient's life in form of decrease of postoperative pain, trismus, and swelling. Furthermore, it enhances bone quality within the extraction socket and bone quantity along the distal aspect of the mandibular second molar. PMID:27597866

Assessment of Pb, Cd, Cr and Ag leaching from electronics waste using four extraction methods.

PubMed

Keith, Ashley; Keesling, Kara; Fitzwater, Kendra K; Pichtel, John; Houy, Denise

2008-12-01

Heavy metals present in electronic components may leach upon disposal and therefore pose significant environmental hazards. The potential leaching of Pb, Cd, Cr and Ag from PC cathode ray tubes, printed circuit boards (PCBs), PC mice, TV remote controls, and mobile phones was assessed. After controlled crushing, each component was extracted using the Toxicity Characteristic Leaching Procedure (TCLP), EPA Method 1312 (SPLP), NEN 7371 (Dutch Environmental Agency), and DIN S4 (Germany). The TCLP consistently leached the greatest amounts of Pb from all components. The SPLP, NEN 7371 and DIN S4 extracted relatively small amounts of metals compared with the TCLP and were not considered effective as leaching tests for e-waste. The smallest size fraction (< 2 mm) of CRT glass and PCBs leached significantly (p < 0.05) highest Pb via the TCLP. A modified TCLP removed 50.9% more extractable Pb compared with the conventional procedure.

Analysis of trace contamination of phthalate esters in ultrapure water using a modified solid-phase extraction procedure and automated thermal desorption-gas chromatography/mass spectrometry.

PubMed

Liu, Hsu-Chuan; Den, Walter; Chan, Shu-Fei; Kin, Kuan Tzu

2008-04-25

The present study was aimed to develop a procedure modified from the conventional solid-phase extraction (SPE) method for the analysis of trace concentration of phthalate esters in industrial ultrapure water (UPW). The proposed procedure allows UPW sample to be drawn through a sampling tube containing hydrophobic sorbent (Tenax TA) to concentrate the aqueous phthalate esters. The solid trap was then demoisturized by two-stage gas drying before subjecting to thermal desorption and analysis by gas chromatography-mass spectrometry. This process removes the solvent extraction procedure necessary for the conventional SPE method, and permits automation of the analytical procedure for high-volume analyses. Several important parameters, including desorption temperature and duration, packing quantity and demoisturizing procedure, were optimized in this study based on the analytical sensitivity for a standard mixture containing five different phthalate esters. The method detection limits for the five phthalate esters were between 36 ng l(-1) and 95 ng l(-1) and recovery rates between 15% and 101%. Dioctyl phthalate (DOP) was not recovered adequately because the compound was both poorly adsorbed and desorbed on and off Tenax TA sorbents. Furthermore, analyses of material leaching from poly(vinyl chloride) (PVC) tubes as well as the actual water samples showed that di-n-butyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) were the common contaminants detected from PVC contaminated UPW and the actual UPW, as well as in tap water. The reduction of DEHP in the production processes of actual UPW was clearly observed, however a DEHP concentration of 0.20 microg l(-1) at the point of use was still being quantified, suggesting that the contamination of phthalate esters could present a barrier to the future cleanliness requirement of UPW. The work demonstrated that the proposed modified SPE procedure provided an effective method for rapid analysis and contamination identification in UPW production lines.

Extraction and derivatization of polar herbicides for GC-MS analyses.

PubMed

Ranz, Andreas; Maier, Eveline; Motter, Herbert; Lankmayr, Ernst

2008-09-01

A sample preparation procedure including a simultaneous microwave-assisted (MA) extraction and derivatization for the determination of chlorophenoxy acids in soil samples is presented. For a selective and sensitive measurement, an analytical technique such as GC coupled with MS needs to be adopted. For GC analyses, chlorophenoxy acids have to be converted into more volatile and thermally stable derivatives. Derivatization by means of microwave radiation offers new alternatives in terms of shorter derivatization time and reduces susceptibility for the formation of artefacts. Extraction and derivatization into methyl esters (ME) were performed with sulphuric acid and methanol. Due to the novelty of the simultaneous extraction and derivatization assisted by means of microwave radiation, a careful investigation and optimization of influential reaction parameters was necessary. It could be shown that the combination of sulphuric acid and methanol provides a fast sample preparation including an efficient clean up procedure. The data obtained by the described method are in good agreement with those published for the reference material. Finally, compared to conventional heating and also to the standard procedure of the EPA, the sample preparation time could be considerably shortened.

The optimization of essential oils supercritical CO2 extraction from Lavandula hybrida through static-dynamic steps procedure and semi-continuous technique using response surface method

PubMed Central

Kamali, Hossein; Aminimoghadamfarouj, Noushin; Golmakani, Ebrahim; Nematollahi, Alireza

2015-01-01

Aim: The aim of this study was to examine and evaluate crucial variables in essential oils extraction process from Lavandula hybrida through static-dynamic and semi-continuous techniques using response surface method. Materials and Methods: Essential oil components were extracted from Lavandula hybrida (Lavandin) flowers using supercritical carbon dioxide via static-dynamic steps (SDS) procedure, and semi-continuous (SC) technique. Results: Using response surface method the optimum extraction yield (4.768%) was obtained via SDS at 108.7 bar, 48.5°C, 120 min (static: 8×15), 24 min (dynamic: 8×3 min) in contrast to the 4.620% extraction yield for the SC at 111.6 bar, 49.2°C, 14 min (static), 121.1 min (dynamic). Conclusion: The results indicated that a substantial reduction (81.56%) solvent usage (kg CO2/g oil) is observed in the SDS method versus the conventional SC method. PMID:25598636

Meta-Analysis: Application to Clinical Dentistry and Dental Education.

ERIC Educational Resources Information Center

Cohen, Peter A.

1992-01-01

Meta-analysis is proposed as an effective alternative to conventional narrative review for extracting trends from research findings. This type of analysis is explained, advantages over more traditional review techniques are discussed, basic procedures and limitations are outlined, and potential applications in dental education and clinical…

Application of dual-cloud point extraction for the trace levels of copper in serum of different viral hepatitis patients by flame atomic absorption spectrometry: a multivariate study.

PubMed

Arain, Salma Aslam; Kazi, Tasneem G; Afridi, Hassan Imran; Abbasi, Abdul Rasool; Panhwar, Abdul Haleem; Naeemullah; Shanker, Bhawani; Arain, Mohammad Balal

2014-12-10

An efficient, innovative preconcentration method, dual-cloud point extraction (d-CPE) has been developed for the extraction and preconcentration of copper (Cu(2+)) in serum samples of different viral hepatitis patients prior to couple with flame atomic absorption spectrometry (FAAS). The d-CPE procedure was based on forming complexes of elemental ions with complexing reagent 1-(2-pyridylazo)-2-naphthol (PAN), and subsequent entrapping the complexes in nonionic surfactant (Triton X-114). Then the surfactant rich phase containing the metal complexes was treated with aqueous nitric acid solution, and metal ions were back extracted into the aqueous phase, as second cloud point extraction stage, and finally determined by flame atomic absorption spectrometry using conventional nebulization. The multivariate strategy was applied to estimate the optimum values of experimental variables for the recovery of Cu(2+) using d-CPE. In optimum experimental conditions, the limit of detection and the enrichment factor were 0.046μgL(-1) and 78, respectively. The validity and accuracy of proposed method were checked by analysis of Cu(2+) in certified sample of serum (CRM) by d-CPE and conventional CPE procedure on same CRM. The proposed method was successfully applied to the determination of Cu(2+) in serum samples of different viral hepatitis patients and healthy controls. Copyright © 2014 Elsevier B.V. All rights reserved.

"In situ" extraction of essential oils by use of Dean-Stark glassware and a Vigreux column inside a microwave oven: a procedure for teaching green analytical chemistry.

PubMed

Chemat, Farid; Perino-Issartier, Sandrine; Petitcolas, Emmanuel; Fernandez, Xavier

2012-08-01

One of the principal objectives of sustainable and green processing development remains the dissemination and teaching of green chemistry in colleges, high schools, and academic laboratories. This paper describes simple glassware that illustrates the phenomenon of extraction in a conventional microwave oven as energy source and a process for green analytical chemistry. Simple glassware comprising a Dean-Stark apparatus (for extraction of aromatic plant material and recovery of essential oils and distilled water) and a Vigreux column (as an air-cooled condenser inside the microwave oven) was designed as an in-situ extraction vessel inside a microwave oven. The efficiency of this experiment was validated for extraction of essential oils from 30 g fresh orange peel, a by-product in the production of orange juice. Every laboratory throughout the world can use this equipment. The microwave power is 100 W and the irradiation time 15 min. The method is performed at atmospheric pressure without added solvent or water and furnishes essential oils similar to those obtained by conventional hydro or steam distillation. By use of GC-MS, 22 compounds in orange peel were separated and identified; the main compounds were limonene (72.1%), β-pinene (8.4%), and γ-terpinene (6.9%). This procedure is appropriate for the teaching laboratory, does not require any special microwave equipment, and enables the students to learn the skills of extraction, and chromatographic and spectroscopic analysis. They are also exposed to a dramatic visual example of rapid, sustainable, and green extraction of an essential oil, and are introduced to successful sustainable and green analytical chemistry.

Direct ultrasonic agitation for rapid extraction of organic matter from airborne particulate.

PubMed

Lee, S C; Zou, S C; Ho, K F; Chan, L Y

2001-01-02

Direct ultrasonic extraction (DUE) is proposed as simple and rapid sample pretreatment method. This new approach is applied to the extraction of particulate organic matter (POM) from airborne particulate by using dichloromethane (DCM) or DCM/methanol (90/10, v/v) as extractant. The analytical determination was carried out by weighing the extractable POM on an electrobalance. Total recovery for POM could be obtained when the sample was extracted three times with 25-50 mL extractant each for about 5 min at 50 W ultrasonic power. In comparison with conventional Soxhlet extraction, less extraction time (total 15 min only) and solvent consumption (100 mL) were required by DUE. The efficiency of the DUE was similar or even higher than the routine Soxhlet method. Additionally, the new extractor is very simple and easy to use and can accelerate the extraction procedures of organic components from various solid samples.

LC-MS metabolic profiling of Arabidopsis thaliana plant leaves and cell cultures: optimization of pre-LC-MS procedure parameters.

PubMed

t'Kindt, Ruben; De Veylder, Lieven; Storme, Michael; Deforce, Dieter; Van Bocxlaer, Jan

2008-08-01

This study treats the optimization of methods for homogenizing Arabidopsis thaliana plant leaves as well as cell cultures, and extracting their metabolites for metabolomics analysis by conventional liquid chromatography electrospray ionization mass spectrometry (LC-ESI/MS). Absolute recovery, process efficiency and procedure repeatability have been compared between different pre-LC-MS homogenization/extraction procedures through the use of samples fortified before extraction with a range of representative metabolites. Hereby, the magnitude of the matrix effect observed in the ensuing LC-MS based metabolomics analysis was evaluated. Based on relative recovery and repeatability of key metabolites, comprehensiveness of extraction (number of m/z-retention time pairs) and clean-up potential of the approach (minimum matrix effects), the most appropriate sample pre-treatment was adopted. It combines liquid nitrogen homogenization for plant leaves with thermomixer based extraction using MeOH/H(2)O 80/20. As such, an efficient and highly reproducible LC-MS plant metabolomics set-up is achieved, as illustrated by the obtained results for both LC-MS (8.88%+/-5.16 versus 7.05%+/-4.45) and technical variability (12.53%+/-11.21 versus 9.31%+/-6.65) data in a comparative investigation of A. thaliana plant leaves and cell cultures, respectively.

Portable microwave assisted extraction: An original concept for green analytical chemistry.

PubMed

Perino, Sandrine; Petitcolas, Emmanuel; de la Guardia, Miguel; Chemat, Farid

2013-11-08

This paper describes a portable microwave assisted extraction apparatus (PMAE) for extraction of bioactive compounds especially essential oils and aromas directly in a crop or in a forest. The developed procedure, based on the concept of green analytical chemistry, is appropriate to obtain direct in-field information about the level of essential oils in natural samples and to illustrate green chemical lesson and research. The efficiency of this experiment was validated for the extraction of essential oil of rosemary directly in a crop and allows obtaining a quantitative information on the content of essential oil, which was similar to that obtained by conventional methods in the laboratory. Copyright © 2013 Elsevier B.V. All rights reserved.

Method of low pressure and/or evaporative drying of aerogel

DOEpatents

Mayer, Steven T.; Kaschmitter, James L.; Pekala, Richard W.

1995-01-01

A process whereby Resorcinol/Formaldehyde (RF) aerogel having a density of about 0.4-1.2 g/cc can be manufactured using a simple air drying procedure. This process is inherently simpler, quicker, and less expensive than the more conventional supercritical or subcritical CO.sub.2 extraction procedures. RF aerogels can be used as produced, such as in insulation applications, or pyrolyzed to form carbon aerogels with a density of about 0.9 g/cc for use in applications such as batteries, supercapacitors, etc.

The use of multimedia consent programs for surgical procedures: a systematic review.

PubMed

Nehme, Jean; El-Khani, Ussamah; Chow, Andre; Hakky, Sherif; Ahmed, Ahmed R; Purkayastha, Sanjay

2013-02-01

To compare multimedia and standard consent, in respect to patient comprehension, anxiety, and satisfaction, for various surgical/interventional procedures. Electronic searches of PubMed, MEDLINE, Ovid, Embase, and Google Scholar were performed. Relevant articles were assessed by 2 independent reviewers. Comparative (randomized and nonrandomized control trials) studies of multimedia and standard consent for a variety of surgical/interventional procedures were included. Studies had to report on at least one of the outcome measures. Studies were reviewed by 2 independent investigators. The first investigator extracted all relevant data, and consensus of each extraction was performed by a second investigator to verify the data. Overall, this review suggests that the use of multimedia as an adjunct to conventional consent appears to improve patient comprehension. Multimedia leads to high patient satisfaction in terms of feasibility, ease of use, and availability of information. There is no conclusive evidence demonstrating a significant reduction in preoperative anxiety.

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.

Direct PCR Offers a Fast and Reliable Alternative to Conventional DNA Isolation Methods for Gut Microbiomes.

PubMed

Videvall, Elin; Strandh, Maria; Engelbrecht, Anel; Cloete, Schalk; Cornwallis, Charlie K

2017-01-01

The gut microbiome of animals is emerging as an important factor influencing ecological and evolutionary processes. A major bottleneck in obtaining microbiome data from large numbers of samples is the time-consuming laboratory procedures required, specifically the isolation of DNA and generation of amplicon libraries. Recently, direct PCR kits have been developed that circumvent conventional DNA extraction steps, thereby streamlining the laboratory process by reducing preparation time and costs. However, the reliability and efficacy of direct PCR for measuring host microbiomes have not yet been investigated other than in humans with 454 sequencing. Here, we conduct a comprehensive evaluation of the microbial communities obtained with direct PCR and the widely used Mo Bio PowerSoil DNA extraction kit in five distinct gut sample types (ileum, cecum, colon, feces, and cloaca) from 20 juvenile ostriches, using 16S rRNA Illumina MiSeq sequencing. We found that direct PCR was highly comparable over a range of measures to the DNA extraction method in cecal, colon, and fecal samples. However, the two methods significantly differed in samples with comparably low bacterial biomass: cloacal and especially ileal samples. We also sequenced 100 replicate sample pairs to evaluate repeatability during both extraction and PCR stages and found that both methods were highly consistent for cecal, colon, and fecal samples ( r s > 0.7) but had low repeatability for cloacal ( r s = 0.39) and ileal ( r s = -0.24) samples. This study indicates that direct PCR provides a fast, cheap, and reliable alternative to conventional DNA extraction methods for retrieving 16S rRNA data, which can aid future gut microbiome studies. IMPORTANCE The microbial communities of animals can have large impacts on their hosts, and the number of studies using high-throughput sequencing to measure gut microbiomes is rapidly increasing. However, the library preparation procedure in microbiome research is both costly and time-consuming, especially for large numbers of samples. We investigated a cheaper and faster direct PCR method designed to bypass the DNA isolation steps during 16S rRNA library preparation and compared it with a standard DNA extraction method. We used both techniques on five different gut sample types collected from 20 juvenile ostriches and sequenced samples with Illumina MiSeq. The methods were highly comparable and highly repeatable in three sample types with high microbial biomass (cecum, colon, and feces), but larger differences and low repeatability were found in the microbiomes obtained from the ileum and cloaca. These results will help microbiome researchers assess library preparation procedures and plan their studies accordingly.

Focused microwave-assisted extraction combined with solid-phase microextraction and gas chromatography-mass spectrometry for the selective analysis of cocaine from coca leaves.

PubMed

Bieri, Stefan; Ilias, Yara; Bicchi, Carlo; Veuthey, Jean-Luc; Christen, Philippe

2006-04-21

An effective combination of focused microwave-assisted extraction (FMAE) with solid-phase microextraction (SPME) prior to gas chromatography (GC) is described for the selective extraction and quantitative analysis of cocaine from coca leaves (Erythroxylum coca). This approach required switching from an organic extraction solvent to an aqueous medium more compatible with SPME liquid sampling. SPME was performed in the direct immersion mode with a universal 100 microm polydimethylsiloxane (PDMS) coated fibre. Parameters influencing this extraction step, such as solution pH, sampling time and temperature are discussed. Furthermore, the overall extraction process takes into account the stability of cocaine in alkaline aqueous solutions at different temperatures. Cocaine degradation rate was determined by capillary electrophoresis using the short end injection procedure. In the selected extraction conditions, less than 5% of cocaine was degraded after 60 min. From a qualitative point of view, a significant gain in selectivity was obtained with the incorporation of SPME in the extraction procedure. As a consequence of SPME clean-up, shorter columns could be used and analysis time was reduced to 6 min compared to 35 min with conventional GC. Quantitative results led to a cocaine content of 0.70 +/- 0.04% in dry leaves (RSD <5%) which agreed with previous investigations.

Closed vessel miniaturized microwave assisted chelating extraction for determination of trace metals in plant materials

NASA Astrophysics Data System (ADS)

Czarnecki, Sezin; Duering, Rolf-Alexander

2013-04-01

In recent years, the use of closed vessel microwave assisted extraction (MAE) for plant samples has shown increasing research interest which will probably substitute conventional procedures in the future due to their general disadvantages including consumption of time and solvents. The objective of this study was to demonstrate an innovative miniaturized closed vessel microwave assisted extraction (µMAE) method under the use of EDTA (µMAE-EDTA) to determine metal contents (Cd, Co, Cu, Mn, Ni, Pb, Zn) in plant samples (Lolio-Cynosuretum) by inductively coupled plasma-optical emission spectrometry (ICP-OES). Validation of the method was done by comparison of the results with another miniaturized closed vessel microwave HNO3 method (µMAE-H) and with two other macro scale MAE procedures (MAE-H and MAE-EDTA) which were applied by using a mixture of nitric acid (HNO3) and hydrogen peroxide (H2O2) (MAE-H) and EDTA (MAE-EDTA), respectively. The already established MAE-H method is taken into consideration as a reference validation MAE method for plant material. A conventional plant extraction (CE) method, based on dry ashing and dissolving of the plant material in HNO3, was used as a confidence comparative method. Certified plant reference materials (CRMs) were used for comparison of recovery rates from different extraction protocols. This allowed the validation of the applicability of the µMAE-EDTA procedure. For 36 real plant samples with triplicates each, µMAE-EDTA showed the same extraction yields as the MAE-H in the determination of Cd, Co, Cu, Mn, Ni, Pb, and Zn contents in plant samples. Analytical parameters in µMAE-EDTA should be further investigated and adapted for other metals of interest. By the reduction and elimination of the use of hazardous chemicals in environmental analysis and thus allowing a better understanding of metal distribution and accumulation process in plants and also the metal transfer from soil to plants and into the food chain, µMAE-EDTA is seen as a promising technique for achieving green chemistry goals.

The use of titanium miniscrews for molar protraction in extraction treatment.

PubMed

Giancotti, Aldo; Greco, Mario; Mampieri, Gianluca; Arcuri, Claudio

2004-01-01

Orthodontic space closure in the mandibular arch by protraction of the mandibular second molars, after the extraction of first molars, may sometimes result in loss of incisor anchorage when using conventional orthodontic procedures. The introduction of miniscrews for immediate loading as orthodontic anchorage, has enlarged treatment possibilities. The authors illustrate their clinical experience in an adult patient treated with the extraction of mandibular first molars and the protraction of second and third molars into the extraction sites. Anchorage control was achieved with the surgical insertion of titanium miniscrews for immediate loading in the cortical bone distal to second bicuspids. Space closure was achieved by means of sliding mechanics according to Bidimensional Technique. The position of lower incisors was maintained preventing any detrimental facial effect.

Choice of solvent extraction technique affects fatty acid composition of pistachio (Pistacia vera L.) oil.

PubMed

Abdolshahi, Anna; Majd, Mojtaba Heydari; Rad, Javad Sharifi; Taheri, Mehrdad; Shabani, Aliakbar; Teixeira da Silva, Jaime A

2015-04-01

Pistachio (Pistacia vera L.) oil has important nutritional and therapeutic properties because of its high concentration of essential fatty acids. The extraction method used to obtain natural compounds from raw material is critical for product quality, in particular to protect nutritional value. This study compared the fatty acid composition of pistachio oil extracted by two conventional procedures, Soxhlet extraction and maceration, analyzed by a gas chromatography-flame ionization detector (GC-FID). Four solvents with different polarities were tested: n-hexane (Hx), dichloromethane (DCM), ethyl acetate (EtAc) and ethanol (EtOH). The highest unsaturated fatty acid content (88.493 %) was obtained by Soxhlet extraction with EtAc. The Soxhlet method extracted the most oleic and linolenic acids (51.99 % and 0.385 %, respectively) although a higher concentration (36.32 %) of linoleic acid was extracted by maceration.

Method of low pressure and/or evaporative drying of aerogel

DOEpatents

Mayer, S.T.; Kaschmitter, J.L.; Pekala, R.W.

1995-05-30

A process is described whereby Resorcinol/Formaldehyde (RF) aerogel having a density of about 0.4--1.2 g/cc can be manufactured using a simple air drying procedure. This process is inherently simpler, quicker, and less expensive than the more conventional supercritical or subcritical CO{sub 2} extraction procedures. RF aerogels can be used as produced, such as in insulation applications, or pyrolyzed to form carbon aerogels with a density of about 0.9 g/cc for use in applications such as batteries, supercapacitors, etc.

Chemical processing of three-dimensional graphene networks on transparent conducting electrodes for depleted-heterojunction quantum dot solar cells.

PubMed

Tavakoli, Mohammad Mahdi; Simchi, Abdolreza; Fan, Zhiyong; Aashuri, Hossein

2016-01-07

We present a novel chemical procedure to prepare three-dimensional graphene networks (3DGNs) as a transparent conductive film to enhance the photovoltaic performance of PbS quantum-dot (QD) solar cells. It is shown that 3DGN electrodes enhance electron extraction, yielding a 30% improvement in performance compared with the conventional device.

Extracting land use information from the earth resources technology satellite data by conventional interpretation methods

NASA Technical Reports Server (NTRS)

Vegas, P. L.

1974-01-01

A procedure for obtaining land use data from satellite imagery by the use of conventional interpretation methods is presented. The satellite is described briefly, and the advantages of various scales and multispectral scanner bands are discussed. Methods for obtaining satellite imagery and the sources of this imagery are given. Equipment used in the study is described, and samples of land use maps derived from satellite imagery are included together with the land use classification system used. Accuracy percentages are cited and are compared to those of a previous experiment using small scale aerial photography.

FOCIS: A forest classification and inventory system using LANDSAT and digital terrain data

NASA Technical Reports Server (NTRS)

Strahler, A. H.; Franklin, J.; Woodcook, C. E.; Logan, T. L.

1981-01-01

Accurate, cost-effective stratification of forest vegetation and timber inventory is the primary goal of a Forest Classification and Inventory System (FOCIS). Conventional timber stratification using photointerpretation can be time-consuming, costly, and inconsistent from analyst to analyst. FOCIS was designed to overcome these problems by using machine processing techniques to extract and process tonal, textural, and terrain information from registered LANDSAT multispectral and digital terrain data. Comparison of samples from timber strata identified by conventional procedures showed that both have about the same potential to reduce the variance of timber volume estimates over simple random sampling.

Application of Ionic Liquids in the Microwave-Assisted Extraction of Proanthocyanidins from Larix gmelini Bark

PubMed Central

Yang, Lei; Sun, Xiaowei; Yang, Fengjian; Zhao, Chunjian; Zhang, Lin; Zu, Yuangang

2012-01-01

Ionic liquid based, microwave-assisted extraction (ILMAE) was successfully applied to the extraction of proanthocyanidins from Larix gmelini bark. In this work, in order to evaluate the performance of ionic liquids in the microwave-assisted extraction process, a series of 1-alkyl-3-methylimidazolium ionic liquids with different cations and anions were evaluated for extraction yield, and 1-butyl-3-methylimidazolium bromide was selected as the optimal solvent. In addition, the ILMAE procedure for the proanthocyanidins was optimized and compared with other conventional extraction techniques. Under the optimized conditions, satisfactory extraction yield of the proanthocyanidins was obtained. Relative to other methods, the proposed approach provided higher extraction yield and lower energy consumption. The Larix gmelini bark samples before and after extraction were analyzed by Thermal gravimetric analysis, Fourier-transform infrared spectroscopy and characterized by scanning electron microscopy. The results showed that the ILMAE method is a simple and efficient technique for sample preparation. PMID:22606036

[Evaluation of mass spectrometry: MALDI-TOF MS for fast and reliable yeast identification].

PubMed

Relloso, María S; Nievas, Jimena; Fares Taie, Santiago; Farquharson, Victoria; Mujica, María T; Romano, Vanesa; Zarate, Mariela S; Smayevsky, Jorgelina

2015-01-01

The matrix-assisted laser desorption/ionization time-of-flight mass spectrometry technique known as MALDI-TOF MS is a tool used for the identification of clinical pathogens by generating a protein spectrum that is unique for a given species. In this study we assessed the identification of clinical yeast isolates by MALDI-TOF MS in a university hospital from Argentina and compared two procedures for protein extraction: a rapid method and a procedure based on the manufacturer's recommendations. A short protein extraction procedure was applied in 100 isolates and the rate of correct identification at genus and species level was 98.0%. In addition, we analyzed 201 isolates, previously identified by conventional methods, using the methodology recommended by the manufacturer and there was 95.38% coincidence in the identification at species level. MALDI TOF MS showed to be a fast, simple and reliable tool for yeast identification. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Ultrasonication followed by single-drop microextraction combined with GC/MS for rapid determination of organochlorine pesticides from fish.

PubMed

Shrivas, Kamlesh; Wu, Hui-Fen

2008-02-01

A novel, rapid and simple sample pretreatment technique termed ultrasonication followed by single-drop micro-extraction (U-SDME) has been developed and combined with GC/MS for the determination of organochlorine pesticides (OCPs) in fish. In the present work, the lengthy procedures generally used in the conventional methods like, Soxhlet extraction, supercritical fluid extraction, pressurized liquid extraction and microwave assisted solvent extraction for extraction of OCPs from fish tissues are minimized by the use of two simple extraction procedures. Firstly, OCPs from fish were extracted in organic solvent with ultrasonication and then subsequently preconcentrated by single-drop micro-extraction (SDME). Extraction parameters of ultrasonication and SDME were optimized in spiked sample solution in order to obtain efficient extraction of OCPs from fish tissues. The calibration curves for OCPs were found to be linear between 10-1000 ng/g with correlation of estimations in the range 0.990-0.994. The recoveries obtained in blank fish tissues were ranged from 82.1 to 95.3%. The LOD and RSD for determination of OCPs in fish were 0.5 ng/g and 9.4-10.0%, respectively. The proposed method was applied for the determination of bioconcentration factor in fish after exposure to different concentrations of OCPs in cultured water. The present method avoids the co-extraction of lipids, long extraction steps (>12 h) and large amount of organic solvent for the separation of OCPs. The main advantages of the present method are rapid, selective, sensitive and low cost for the determination of OCPs in fish.

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

Cavanaugh, J.E.; McQuarrie, A.D.; Shumway, R.H.

Conventional methods for discriminating between earthquakes and explosions at regional distances have concentrated on extracting specific features such as amplitude and spectral ratios from the waveforms of the P and S phases. We consider here an optimum nonparametric classification procedure derived from the classical approach to discriminating between two Gaussian processes with unequal spectra. Two robust variations based on the minimum discrimination information statistic and Renyi's entropy are also considered. We compare the optimum classification procedure with various amplitude and spectral ratio discriminants and show that its performance is superior when applied to a small population of 8 land-based earthquakesmore » and 8 mining explosions recorded in Scandinavia. Several parametric characterizations of the notion of complexity based on modeling earthquakes and explosions as autoregressive or modulated autoregressive processes are also proposed and their performance compared with the nonparametric and feature extraction approaches.« less

Extraction of α-humulene-enriched oil from clove using ultrasound-assisted supercritical carbon dioxide extraction and studies of its fictitious solubility.

PubMed

Wei, Ming-Chi; Xiao, Jianbo; Yang, Yu-Chiao

2016-11-01

Clove buds are used as a spice and food flavoring. In this study, clove oil and α-humulene was extracted from cloves using supercritical carbon dioxide extraction with and without ultrasound assistance (USC-CO2 and SC-CO2, respectively) at different temperatures (32-50°C) and pressures (9.0-25.0MPa). The results of these extractions were compared with those of heat reflux extraction and steam distillation methods conducted in parallel. The extracts obtained using these four techniques were analyzed using gas chromatography and gas chromatography/mass spectrometry (GC/MS). The results demonstrated that the USC-CO2 extraction procedure may extract clove oil and α-humulene from clove buds with better yields and shorter extraction times than conventional extraction techniques while utilizing less severe operating parameters. Furthermore, the experimental fictitious solubility data obtained using the dynamic method were well correlated with density-based models, including the Chrastil model, the Bartle model and the Kumar and Johnston model. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cost-effectiveness assessment in outpatient sinonasal surgery.

PubMed

Mortuaire, G; Theis, D; Fackeure, R; Chevalier, D; Gengler, I

2018-02-01

To assess the cost-effectiveness of outpatient sinonasal surgery in terms of clinical efficacy and control of expenses. A retrospective study was conducted from January 2014 to January 2016. Patients scheduled for outpatient sinonasal surgery were systematically included. Clinical data were extracted from surgical and anesthesiology computer files. The cost accounting methods applied in our institution were used to evaluate logistic and technical costs. The standardized hospital fees rating system based on hospital stay and severity in diagnosis-related groups (Groupes homogènes de séjours: GHS) was used to estimate institutional revenue. Over 2years, 927 outpatient surgical procedures were performed. The crossover rate to conventional hospital admission was 2.9%. In a day-1 telephone interview, 85% of patients were very satisfied with the procedure. All outpatient cases showed significantly lower costs than estimated for conventional management with overnight admission, while hospital revenue did not differ between the two. This study confirmed the efficacy of outpatient surgery in this indication. Lower costs could allow savings for the health system by readjusting the rating for the procedure. More precise assessment of cost-effectiveness will require more fine-grained studies based on micro costing at hospital level and assessment of impact on conventional surgical activity and post-discharge community care. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Microwave-assisted extraction and a new determination method for total steroid saponins from Dioscorea zingiberensis C.H. Wright.

PubMed

Ren, Yao; Chen, Yu; Hu, Bohan; Wu, Hui; Lai, Furao; Li, Xiaofeng

2015-12-01

An efficient microwave-assisted extraction (MAE) technique was applied to isolate total steroid saponins from Dioscorea zingiberensis C.H. Wright (DZW). The optimal extracting conditions were established as 75% ethanol as solvent, ratio of solid/liquid 1:20 (g/ml), temperature 75 °C, irradiation power 600 W and three extraction cycles of 6 min each. Scanning electron microscopy (SEM) images of DZW processed by four different extractions provided visual evidence of the disruption effect on DZW. Diosgenin was quantified by HPLC and examined further by LC-ESI/MS after acid hydrolysis. Total steroid saponins were calculated using diosgenin from total steroid saponins. The MAE procedure was optimized, validated and compared with other conventional extraction processes. This report provides a convenient technology for the extraction and quantification of total saponins of DZW combining MAE with HPLC and LC-ESI/MS for the first time. Copyright © 2015 Elsevier Inc. All rights reserved.

Ultrasound assisted extraction of food and natural products. Mechanisms, techniques, combinations, protocols and applications. A review.

PubMed

Chemat, Farid; Rombaut, Natacha; Sicaire, Anne-Gaëlle; Meullemiestre, Alice; Fabiano-Tixier, Anne-Sylvie; Abert-Vian, Maryline

2017-01-01

This review presents a complete picture of current knowledge on ultrasound-assisted extraction (UAE) in food ingredients and products, nutraceutics, cosmetic, pharmaceutical and bioenergy applications. It provides the necessary theoretical background and some details about extraction by ultrasound, the techniques and their combinations, the mechanisms (fragmentation, erosion, capillarity, detexturation, and sonoporation), applications from laboratory to industry, security, and environmental impacts. In addition, the ultrasound extraction procedures and the important parameters influencing its performance are also included, together with the advantages and the drawbacks of each UAE techniques. Ultrasound-assisted extraction is a research topic, which affects several fields of modern plant-based chemistry. All the reported applications have shown that ultrasound-assisted extraction is a green and economically viable alternative to conventional techniques for food and natural products. The main benefits are decrease of extraction and processing time, the amount of energy and solvents used, unit operations, and CO 2 emissions. Copyright © 2016 Elsevier B.V. All rights reserved.

"Solvent-free" ultrasound-assisted extraction of lipids from fresh microalgae cells: a green, clean and scalable process.

PubMed

Adam, Fanny; Abert-Vian, Maryline; Peltier, Gilles; Chemat, Farid

2012-06-01

In order to comply with criteria of green chemistry concepts and sustainability, a new procedure has been performed for solvent-free ultrasound-assisted extraction (UAE) to extract lipids from fresh Nannochloropsis oculata biomass. Through response surface methodology (RSM) parameters affecting the oil recovery were optimized. Optimum conditions for oil extraction were estimated as follows: (i) 1000 W ultrasonic power, (ii) 30 min extraction time and (iii) biomass dry weight content at 5%. Yields were calculated by the total fatty acids methyl esters amounts analyzed by GC-FID-MS. The maximum oil recovery was around 0.21%. This value was compared with the one obtained with the conventional extraction method (Bligh and Dyer). Furthermore, effect of temperature on the yield was also investigated. The overall results show an innovative and effective extraction method adapted for microalgae oil recovery, without using solvent and with an enable scaling up. Copyright © 2012 Elsevier Ltd. All rights reserved.

Green ultrasound-assisted extraction of carotenoids from pomegranate wastes using vegetable oils.

PubMed

Goula, Athanasia M; Ververi, Maria; Adamopoulou, Anna; Kaderides, Kyriakos

2017-01-01

The objective of this work was to develop a new process for pomegranate peels application in food industries based on ultrasound-assisted extraction of carotenoids using different vegetable oils as solvents. In this way, an oil enriched with antioxidants is produced. Sunflower oil and soy oil were used as alternative solvents and the effects of various parameters on extraction yield were studied. Extraction temperature, solid/oil ratio, amplitude level, and extraction time were the factors investigated with respect to extraction yield. Comparative studies between ultrasound-assisted and conventional solvent extraction were carried out in terms of processing procedure and total carotenoids content. The efficient extraction period for achieving maximum yield of pomegranate peel carotenoids was about 30min. The optimum operating conditions were found to be: extraction temperature, 51.5°C; peels/solvent ratio, 0.10; amplitude level, 58.8%; solvent, sunflower oil. A second-order kinetic model was successfully developed for describing the mechanism of ultrasound extraction under different processing parameters. Copyright © 2016 Elsevier B.V. All rights reserved.

Cost-Effectiveness of Procedures for Treatment of Ostium Secundum Atrial Septal Defects Occlusion Comparing Conventional Surgery and Septal Percutaneous Implant

PubMed Central

da Costa, Márcia Gisele Santos; Santos, Marisa da Silva; Sarti, Flávia Mori; Senna, Kátia Marie Simões e.; Tura, Bernardo Rangel; Goulart, Marcelo Correia

2014-01-01

Objectives The study performs a cost-effectiveness analysis of procedures for atrial septal defects occlusion, comparing conventional surgery to septal percutaneous implant. Methods A model of analytical decision was structured with symmetric branches to estimate cost-effectiveness ratio between the procedures. The decision tree model was based on evidences gathered through meta-analysis of literature, and validated by a panel of specialists. The lower number of surgical procedures performed for atrial septal defects occlusion at each branch was considered as the effectiveness outcome. Direct medical costs and probabilities for each event were inserted in the model using data available from Brazilian public sector database system and information extracted from the literature review, using micro-costing technique. Sensitivity analysis included price variations of percutaneous implant. Results The results obtained from the decision model demonstrated that the percutaneous implant was more cost effective in cost-effectiveness analysis at a cost of US$8,936.34 with a reduction in the probability of surgery occurrence in 93% of the cases. Probability of atrial septal communication occlusion and cost of the implant are the determinant factors of cost-effectiveness ratio. Conclusions The proposal of a decision model seeks to fill a void in the academic literature. The decision model proposed includes the outcomes that present major impact in relation to the overall costs of the procedure. The atrial septal defects occlusion using percutaneous implant reduces the physical and psychological distress to the patients in relation to the conventional surgery, which represent intangible costs in the context of economic evaluation. PMID:25302806

Cost-effectiveness of procedures for treatment of ostium secundum atrial septal defects occlusion comparing conventional surgery and septal percutaneous implant.

PubMed

da Costa, Márcia Gisele Santos; Santos, Marisa da Silva; Sarti, Flávia Mori; Simões e Senna, Kátia Marie; Tura, Bernardo Rangel; Correia, Marcelo Goulart; Goulart, Marcelo Correia

2014-01-01

The study performs a cost-effectiveness analysis of procedures for atrial septal defects occlusion, comparing conventional surgery to septal percutaneous implant. A model of analytical decision was structured with symmetric branches to estimate cost-effectiveness ratio between the procedures. The decision tree model was based on evidences gathered through meta-analysis of literature, and validated by a panel of specialists. The lower number of surgical procedures performed for atrial septal defects occlusion at each branch was considered as the effectiveness outcome. Direct medical costs and probabilities for each event were inserted in the model using data available from Brazilian public sector database system and information extracted from the literature review, using micro-costing technique. Sensitivity analysis included price variations of percutaneous implant. The results obtained from the decision model demonstrated that the percutaneous implant was more cost effective in cost-effectiveness analysis at a cost of US$8,936.34 with a reduction in the probability of surgery occurrence in 93% of the cases. Probability of atrial septal communication occlusion and cost of the implant are the determinant factors of cost-effectiveness ratio. The proposal of a decision model seeks to fill a void in the academic literature. The decision model proposed includes the outcomes that present major impact in relation to the overall costs of the procedure. The atrial septal defects occlusion using percutaneous implant reduces the physical and psychological distress to the patients in relation to the conventional surgery, which represent intangible costs in the context of economic evaluation.

Liquid by-products from fish canning industry as sustainable sources of ω3 lipids.

PubMed

Monteiro, Ana; Paquincha, Diogo; Martins, Florinda; Queirós, Rui P; Saraiva, Jorge A; Švarc-Gajić, Jaroslava; Nastić, Nataša; Delerue-Matos, Cristina; Carvalho, Ana P

2018-08-01

Fish canning industry generates large amounts of liquid wastes, which are discarded, after proper treatment to remove the organic load. However, alternative treatment processes may also be designed in order to target the recovery of valuable compounds; with this procedure, these wastewaters are converted into liquid by-products, becoming an additional source of revenue for the company. This study evaluated green and economically sustainable methodologies for the extraction of ω3 lipids from fish canning liquid by-products. Lipids were extracted by processes combining physical and chemical parameters (conventional and pressurized extraction processes), as well as chemical and biological parameters. Furthermore, LCA was applied to evaluate the environmental performance and costs indicators for each process. Results indicated that extraction with high hydrostatic pressure provides the highest amounts of ω3 polyunsaturated fatty acids (3331,5 mg L -1 effluent), apart from presenting the lowest environmental impact and costs. The studied procedures allow to obtain alternative, sustainable and traceable sources of ω3 lipids for further applications in food, pharmaceutical and cosmetic industries. Additionally, such approach contributes towards the organic depuration of canning liquid effluents, therefore reducing the overall waste treatment costs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Impact of ultrasound on solid-liquid extraction of phenolic compounds from maritime pine sawdust waste. Kinetics, optimization and large scale experiments.

PubMed

Meullemiestre, A; Petitcolas, E; Maache-Rezzoug, Z; Chemat, F; Rezzoug, S A

2016-01-01

Maritime pine sawdust, a by-product from industry of wood transformation, has been investigated as a potential source of polyphenols which were extracted by ultrasound-assisted maceration (UAM). UAM was optimized for enhancing extraction efficiency of polyphenols and reducing time-consuming. In a first time, a preliminary study was carried out to optimize the solid/liquid ratio (6g of dry material per mL) and the particle size (0.26 cm(2)) by conventional maceration (CVM). Under these conditions, the optimum conditions for polyphenols extraction by UAM, obtained by response surface methodology, were 0.67 W/cm(2) for the ultrasonic intensity (UI), 40°C for the processing temperature (T) and 43 min for the sonication time (t). UAM was compared with CVM, the results showed that the quantity of polyphenols was improved by 40% (342.4 and 233.5mg of catechin equivalent per 100g of dry basis, respectively for UAM and CVM). A multistage cross-current extraction procedure allowed evaluating the real impact of UAM on the solid-liquid extraction enhancement. The potential industrialization of this procedure was implemented through a transition from a lab sonicated reactor (3 L) to a large scale one with 30 L volume. Copyright © 2015 Elsevier B.V. All rights reserved.

Decision rules for unbiased inventory estimates

NASA Technical Reports Server (NTRS)

Argentiero, P. D.; Koch, D.

1979-01-01

An efficient and accurate procedure for estimating inventories from remote sensing scenes is presented. In place of the conventional and expensive full dimensional Bayes decision rule, a one-dimensional feature extraction and classification technique was employed. It is shown that this efficient decision rule can be used to develop unbiased inventory estimates and that for large sample sizes typical of satellite derived remote sensing scenes, resulting accuracies are comparable or superior to more expensive alternative procedures. Mathematical details of the procedure are provided in the body of the report and in the appendix. Results of a numerical simulation of the technique using statistics obtained from an observed LANDSAT scene are included. The simulation demonstrates the effectiveness of the technique in computing accurate inventory estimates.

A new method for microwave assisted ethanolic extraction of Mentha rotundifolia bioactive terpenoids.

PubMed

García-Sarrió, María Jesús; Sanz, María Luz; Sanz, Jesús; González-Coloma, Azucena; Cristina Soria, Ana

2018-04-14

A new microwave-assisted extraction (MAE) method using ethanol as solvent has been optimized by means of a Box-Behnken experimental design for the enhanced extraction of bioactive terpenoids from Mentha rotundifolia leaves; 100°C, 5 min, 1.125 g dry sample: 10 mL solvent and a single extraction cycle were selected as optimal conditions. Improved performance of MAE method in terms of extraction yield and/or reproducibility over conventional solid-liquid extraction and ultrasound assisted extraction was also previously assessed. A comprehensive characterization of MAE extracts was carried out by GC-MS. A total of 46 compounds, mostly terpenoids, were identified; piperitenone oxide and piperitenone were the major compounds determined. Several neophytadiene isomers were also detected for the first time in MAE extracts. Different procedures (solid-phase extraction and activated charcoal (AC) treatment) were also evaluated for clean-up of MAE extracts, with AC providing the highest enrichment in bioactive terpenoids. Finally, the MAE method here developed is shown as a green, fast, efficient and reproducible liquid extraction methodology to obtain M. rotundifolia bioactive extracts for further application, among others, as food preservatives. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Novel Procedure for the Immediate Reconstruction of Severely Resorbed Alveolar Sockets for Advanced Periodontal Disease.

PubMed

Aimetti, Mario; Manavella, Valeria; Cricenti, Luca; Romano, Federica

2017-01-01

Background. Several clinical techniques and a variety of biomaterials have been introduced over the years in an effort to overcome bone remodeling and resorption after tooth extraction. However, the predictability of these procedures in sockets with severely resorbed buccal/lingual plate due to periodontal disease is still unknown. Case Description. A patient with advanced periodontitis underwent extraction of upper right lateral and central incisors. The central incisor exhibited complete buccal bone plate loss and a 9 mm vertical bone deficiency on its palatal side. The alveolar sockets were filled with collagen sponge and covered with a nonresorbable high-density PTFE membrane. Primary closure was not attained and any rigid scaffold material was not used. Histologic analysis provided evidence of new bone formation. At 12 months a cone-beam computed tomographic scan revealed enough bone volume to insert two conventional dental implants in conjunction with minor horizontal bone augmentation procedures. Clinical Implications. This case report would seem to support the potential of the proposed reconstructive approach in changing the morphology of severely resorbed alveolar sockets, minimizing the need for advanced bone regeneration procedures during implant placement.

A Novel Procedure for the Immediate Reconstruction of Severely Resorbed Alveolar Sockets for Advanced Periodontal Disease

PubMed Central

2017-01-01

Background. Several clinical techniques and a variety of biomaterials have been introduced over the years in an effort to overcome bone remodeling and resorption after tooth extraction. However, the predictability of these procedures in sockets with severely resorbed buccal/lingual plate due to periodontal disease is still unknown. Case Description. A patient with advanced periodontitis underwent extraction of upper right lateral and central incisors. The central incisor exhibited complete buccal bone plate loss and a 9 mm vertical bone deficiency on its palatal side. The alveolar sockets were filled with collagen sponge and covered with a nonresorbable high-density PTFE membrane. Primary closure was not attained and any rigid scaffold material was not used. Histologic analysis provided evidence of new bone formation. At 12 months a cone-beam computed tomographic scan revealed enough bone volume to insert two conventional dental implants in conjunction with minor horizontal bone augmentation procedures. Clinical Implications. This case report would seem to support the potential of the proposed reconstructive approach in changing the morphology of severely resorbed alveolar sockets, minimizing the need for advanced bone regeneration procedures during implant placement. PMID:28250998

Analysis of flavor compounds by GC/MS after liquid-liquid extraction from fruit juices

NASA Astrophysics Data System (ADS)

Tuşa, F. D.; Moldovan, Z.; Schmutzer, G.; Magdaş, D. A.; Dehelean, A.; Vlassa, M.

2012-02-01

In this work we describe a rapid method for analysis of volatile profiles of several commercial fruit juices using GC/MS instrument after liquid-liquid extraction. Volatile flavor compounds have been identified based on mass spectrum obtained in EI mode. This method allows to analyses a wide range of flavor compounds (esters, aldehydes, alcohols, terpenoids) the procedure was rapid, simple and inexpensive. Moreover, by means of volatile compounds it could be possible to distinguish between juices of organic and conventional production and those with flavorings addition. More of 20 compounds were identified and quantified as relative chromatogram area taken on larges ion in mass spectrum.

Feature Vector Construction Method for IRIS Recognition

NASA Astrophysics Data System (ADS)

Odinokikh, G.; Fartukov, A.; Korobkin, M.; Yoo, J.

2017-05-01

One of the basic stages of iris recognition pipeline is iris feature vector construction procedure. The procedure represents the extraction of iris texture information relevant to its subsequent comparison. Thorough investigation of feature vectors obtained from iris showed that not all the vector elements are equally relevant. There are two characteristics which determine the vector element utility: fragility and discriminability. Conventional iris feature extraction methods consider the concept of fragility as the feature vector instability without respect to the nature of such instability appearance. This work separates sources of the instability into natural and encodinginduced which helps deeply investigate each source of instability independently. According to the separation concept, a novel approach of iris feature vector construction is proposed. The approach consists of two steps: iris feature extraction using Gabor filtering with optimal parameters and quantization with separated preliminary optimized fragility thresholds. The proposed method has been tested on two different datasets of iris images captured under changing environmental conditions. The testing results show that the proposed method surpasses all the methods considered as a prior art by recognition accuracy on both datasets.

Assessment of bioavailable B vitamin content in food using in vitro digestibility assay and LC-MS SIDA.

PubMed

Paalme, Toomas; Vilbaste, Allan; Kevvai, Kaspar; Nisamedtinov, Ildar; Hälvin-Tanilas, Kristel

2017-11-01

Standardized analytical methods, where each B vitamin is extracted from a given sample individually using separate procedures, typically ensure that the extraction conditions provide the maximum recovery of each vitamin. However, in the human gastrointestinal tract (GIT), the extraction conditions are the same for all vitamins. Here, we present an analytically feasible extraction protocol that simulates conditions in the GIT and provides a measure of the content of bioavailable vitamins using LC-MS stable isotope dilution assay. The results show that the activities of both human gastric and duodenal juices were insufficient to liberate absorbable vitamers (AV) from pure cofactors. The use of an intestinal brush border membrane (IBBM) fraction derived from the mucosal tissue of porcine small intestine ensured at least 70% AV recovery. The rate of AV liberation, however, was strongly dependent on the cofactor, e.g., in the case of NADH, it was magnitudes higher than in the case of thiamine diphosphate. For some vitamins in some food matrices, the use of the IBBM fraction assay resulted in lower values for the content of AV than conventional vitamin determination methods. Conventional methods likely overestimate the actual bioavailability of some vitamins in these cases. Graphical abstract Assessment of bioavailable B vitamin content in food.

Leadless Cardiac Pacemaker Implantation After Lead Extraction in Patients With Severe Device Infection.

PubMed

Kypta, Alexander; Blessberger, Hermann; Kammler, Juergen; Lambert, Thomas; Lichtenauer, Michael; Brandstaetter, Walter; Gabriel, Michael; Steinwender, Clemens

2016-09-01

Conventional pacemaker therapy is limited by short- and long-term complications, most notably device infection. Transcatheter pacing systems (TPS) may be beneficial in this kind of patients as they eliminate the need for a device pocket and leads and thus may reduce the risk of re-infection. We assessed a novel procedure in 6 patients with severe device infection who were pacemaker dependent. After lead extraction a single chamber TPS was implanted into the right ventricle. Of the 6 patients who underwent lead extraction due to severe device infection at our institution, 3 were diagnosed with a pocket infection only, whereas the other 3 showed symptoms of both pocket and lead infection. Successful lead extraction and TPS implantation was accomplished in all patients. Four patients were bridged with a temporary pacemaker between 2 hours and 2 days after lead extraction, whereas 2 patients had the TPS implanted during the same procedure just before traditional pacemaker system removal. All patients stayed free of infection during the follow-up period of 12 weeks. An additional positron emission tomography scan was performed in each patient and indicated no signs of an infection around the TPS. Transcather pacemaker implantation was safe and feasible in 6 patients and did not result in re-infection even if implanted before removal of the infected pacemaker system within the same procedure. Therefore, implantation of a TPS may be an option for patients with severe device infection, especially in those with blocked venous access or who are pacemaker dependent. © 2016 Wiley Periodicals, Inc.

Development of pressurized subcritical water extraction combined with stir bar sorptive extraction for the analysis of organochlorine pesticides and chlorobenzenes in soils.

PubMed

Rodil, Rosario; Popp, Peter

2006-08-18

An analytical method for the determination of several organochlorine pesticides (OCPs) like hexachlorocyclohexanes (HCHs), cyclodiene derivates (dieldrin, aldrin, endrin, heptachlor, heptachlor epoxide, endrin aldehyde, endosulfan and ensodulfan sulphate) and DDX compounds (p,p'-DDE, p,p'-DDD and p,p'-DDT) as well as chlorobenzenes in soils has been developed. The procedure is based on pressurized subcritical water extraction (PSWE) followed by stir bar sorptive extraction (SBSE) and subsequent thermodesorption-gas chromatography/mass spectrometry analysis. Significant PSWE and SBSE parameters were optimized using spiked soil and water samples. For the PSWE of the organochlorine compounds, water modified with acetonitrile as the extraction solvent, at an extraction temperature of 120 degrees C, and three cycles of 10 min extraction proved to be optimal. Under optimized conditions, the figures of merit, such as precision, accuracy and detection limits were evaluated. The detection limits obtained for soil samples were in the range 0.002-4.7 ng/g. Recoveries between 4.1 and 85.2% were achieved from samples spiked at a concentration level of 25-155 ng/g. The main advantages of this method are the avoidance of clean-up and concentration procedures as well as the significant reduction of the required volume of organic solvents. The described method was applied to the determination of the pollutants in soil samples collected from a polluted area, the Bitterfeld region (Germany). The results obtained by PSWE-SBSE were in a good agreement with those obtained by a reference method, a conventional pressurized liquid extraction (PLE).

Determination of rutin and quercetin in Chinese herbal medicine by ionic liquid-based pressurized liquid extraction-liquid chromatography-chemiluminescence detection.

PubMed

Wu, Hongwei; Chen, Meilan; Fan, Yunchang; Elsebaei, Fawzi; Zhu, Yan

2012-01-15

A novel ionic liquid-based pressurized liquid extraction (IL-PLE) procedure coupled with high performance liquid chromatography (HPLC) tandem chemiluminescence (CL) detection capable of quantifying trace amounts of rutin and quercetin in four Chinese medicine plants including Flos sophorae Immaturus, Crateagus pinnatifida Bunge, Hypericum japonicum Thunb and Folium Mori was described in this paper. To avoid environmental pollution and toxicity to the operators, ionic liquids (ILs), 1-alkyl-3-methylimidazolium chloride ([C(n)mim][Cl]) aqueous solutions were used in the PLE procedure as extractants replacing traditional organic solvents. In addition, chemiluminescence detection was utilized for its minimal interference from endogenous components of complex matrix. Parameters affecting extraction and analysis were carefully optimized. Compared with the conventional ultrasonic-assisted extraction (UAE) and heat-reflux extraction (HRE), the optimized method achieved the highest extraction efficiency in the shortest extraction time with the least solvent consumption. The applicability of the proposed method to real sample was confirmed. Under the optimized conditions, good reproducibility of extraction performance was obtained and good linearity was observed with correlation coefficients (r) between 0.9997 and 0.9999. The detection limits of rutin and quercetin (LOD, S/N=3) were 1.1×10(-2)mg/L and 3.8×10(-3)mg/L, respectively. The average recoveries of rutin and quercetin for real samples were 93.7-105% with relative standard deviation (RSD) lower than 5.7%. To the best of our knowledge, this paper is the first contribution to utilize a combination of IL-PLE with chemiluminescence detection. And the experimental results indicated that the proposed method shows a promising prospect in extraction and determination of rutin and quercetin in medicinal plants. Copyright © 2011 Elsevier B.V. All rights reserved.

Dispersed particle extraction--a new procedure for trace element enrichment from natural aqueous samples with subsequent ICP-OES analysis.

PubMed

Bauer, Gerald; Neouze, Marie-Alexandra; Limbeck, Andreas

2013-01-15

A novel sample pre-treatment method for multi trace element enrichment from environmental waters prior to optical emission spectrometry analysis with inductively coupled plasma (ICP-OES) is proposed, based on dispersed particle extraction (DPE). This method is based on the use of silica nanoparticles functionalized with strong cation exchange ligands. After separation from the investigated sample solution, the nanoparticles used for the extraction are directly introduced in the ICP for measurement of the adsorbed target analytes. A prerequisite for the successful application of the developed slurry approach is the use of sorbent particles with a mean size of 500 nm instead of commercially available μm sized beads. The proposed method offers the known advantages of common bead-injection (BI) techniques, and further circumvents the elution step required in conventional solid phase extraction procedures. With the use of 14.4 mL sample and addition of ammonium acetate buffer and particle slurry limits of detection (LODs) from 0.03 μg L(-1) for Be to 0.48 μg L(-1) for Fe, with relative standard deviations ranging from 1.7% for Fe and 5.5% for Cr and an average enrichment factor of 10.4 could be achieved. By implementing this method the possibility to access sorbent materials with irreversible bonding mechanisms for sample pre-treatment is established, thus improvements in the selectivity of sample pre-treatment procedures can be achieved. The presented procedure was tested for accuracy with NIST standard reference material 1643e (fresh water) and was applied to drinking water samples from the vicinity of Vienna. Copyright © 2012 Elsevier B.V. All rights reserved.

A simple and rapid infrared-assisted self enzymolysis extraction method for total flavonoid aglycones extraction from Scutellariae Radix and mechanism exploration.

PubMed

Wang, Liping; Duan, Haotian; Jiang, Jiebing; Long, Jiakun; Yu, Yingjia; Chen, Guiliang; Duan, Gengli

2017-09-01

A new, simple, and fast infrared-assisted self enzymolysis extraction (IRASEE) approach for the extraction of total flavonoid aglycones (TFA) mainly including baicalein, wogonin, and oroxylin A from Scutellariae Radix is presented to enhance extraction yield. Extraction enzymolysis temperature, enzymolysis liquid-to-solid ratio, enzymolysis pH, enzymolysis time and infrared power, the factors affecting IRASEE procedure, were investigated in a newly designed, temperature-controlled infrared-assisted extraction (TC-IRAE) system to acquire the optimum analysis conditions. The results illustrated that IRASEE possessed great advantages in terms of efficiency and time compared with other conventional extraction techniques. Furthermore, the mechanism of IRASEE was preliminarily explored by observing the microscopic change of the samples surface structures, studying the main chemical compositions change of the samples before and after extraction and investigating the kinetics and thermodynamics at three temperature levels during the IRASEE process. These findings revealed that IRASEE can destroy the surface microstructures to accelerate the mass transfer and reduce the activation energy to intensify the chemical process. This integrative study presents a simple, rapid, efficient, and environmental IRASEE method for TFA extraction which has promising prospects for other similar herbal medicines. Graphical Abstract ᅟ.

[Action of Calendula officinalis essence on bone preservation after the extraction].

PubMed

Uribe-Fentanes, Laura K; Soriano-Padilla, Fernando; Pérez-Frutos, Jorge Raúl; Veras-Hernández, Miriam Alejandra

2018-01-01

Calendula officinalis is a phytodrug used as analgesic, antiseptic and wound-healing agent due to its collagenogenic effect, which is why it is a convenient and affordable treatment that promotes alveolar bone preservation after tooth extraction in vivo. The aim of this study was to use Calendula officinalis during and after tooth extraction to determine its ability to preserve bone after this procedure. We established two groups matched by age, gender and position of the third molar. We used with patients on the experimental group Calendula officinalis diluted 10% as an irrigant during surgical extraction of third molars. We performed the conventional way with the control group irrigating with saline solution. Subsequently, both groups continued to make mouthwash for a week with the irrigating agent. Every week for a month, each patient underwent periapical radiography, out of which we took measurements of alveolar ridges and depth of alveolar bone, which were compared. There is statistically significant evidence to state that Calendula officinalis favorably affects bone preservation after extraction.

Extraction of hyaluronic acid (HA) from rooster comb and characterization using flow field-flow fractionation (FlFFF) coupled with multiangle light scattering (MALS).

PubMed

Kang, Dong Young; Kim, Won-Suk; Heo, In Sook; Park, Young Hun; Lee, Seungho

2010-11-01

Hyaluronic acid (HA) was extracted in a relatively large scale from rooster comb using a method similar to that reported previously. The extraction method was modified to simplify and to reduce time and cost in order to accommodate a large-scale extraction. Five hundred grams of frozen rooster combs yielded about 500 mg of dried HA. Extracted HA was characterized using asymmetrical flow field-flow fractionation (AsFlFFF) coupled online to a multiangle light scattering detector and a refractive index detector to determine the molecular size, molecular weight (MW) distribution, and molecular conformation of HA. For characterization of HA, AsFlFFF was operated by a simplified two-step procedure, instead of the conventional three-step procedure, where the first two steps (sample loading and focusing) were combined into one to avoid the adsorption of viscous HA onto the channel membrane. The simplified two-step AsFlFFF yielded reasonably good separations of HA molecules based on their MWs. The weight average MW (M(w) ) and the average root-mean-square (RMS) radius of HA extracted from rooster comb were 1.20×10(6) and 94.7 nm, respectively. When the sample solution was filtered through a 0.45 μm disposable syringe filter, they were reduced down to 3.8×10(5) and 50.1 nm, respectively. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Intraosseous anesthesia with solution injection controlled by a computerized system versus conventional oral anesthesia: a preliminary study.

PubMed

Beneito-Brotons, Rut; Peñarrocha-Oltra, David; Ata-Ali, Javier; Peñarrocha, María

2012-05-01

To compare a computerized intraosseous anesthesia system with the conventional oral anesthesia techniques, and analyze the latency and duration of the anesthetic effect and patient preference. A simple-blind prospective study was made between March 2007 and May 2008. Each patient was subjected to two anesthetic techniques: conventional and intraosseous using the Quicksleeper® system (DHT, Cholet, France). A split-mouth design was adopted in which each patient underwent treatment of a tooth with one of the techniques, and treatment of the homologous contralateral tooth with the other technique. The treatments consisted of restorations, endodontic procedures and simple extractions. The study series comprised 12 females and 18 males with a mean age of 36.8 years. The 30 subjects underwent a total of 60 anesthetic procedures. Intraosseous and conventional oral anesthesia caused discomfort during administration in 46.3% and 32.1% of the patients, respectively. The latency was 7.1±2.23 minutes for the conventional technique and 0.48±0.32 for intraosseous anesthesia--the difference being statistically significant. The depth of the anesthetic effect was sufficient to allow the patients to tolerate the dental treatments. The duration of the anesthetic effect in soft tissues was 199.3 minutes with the conventional technique versus only 1.6 minutes with intraosseous anesthesia--the difference between the two techniques being statistically significant. Most of the patients (69.7%) preferred intraosseous anesthesia. The described intraosseous anesthetic system is effective, with a much shorter latency than the conventional technique, sufficient duration of anesthesia to perform the required dental treatments, and with a much lesser soft tissue anesthetic effect. Most of the patients preferred intraosseous anesthesia.

Intraosseous anesthesia with solution injection controlled by a computerized system versus conventional oral anesthesia: A preliminary study

PubMed Central

Beneito-Brotons, Rut; Peñarrocha-Oltra, David; Ata-Ali, Javier

2012-01-01

Objective: To compare a computerized intraosseous anesthesia system with the conventional oral anesthesia techniques, and analyze the latency and duration of the anesthetic effect and patient preference. Design: A simple-blind prospective study was made between March 2007 and May 2008. Each patient was subjected to two anesthetic techniques: conventional and intraosseous using the Quicksleeper® system (DHT, Cholet, France). A split-mouth design was adopted in which each patient underwent treatment of a tooth with one of the techniques, and treatment of the homologous contralateral tooth with the other technique. The treatments consisted of restorations, endodontic procedures and simple extractions. Results: The study series comprised 12 females and 18 males with a mean age of 36.8 years. The 30 subjects underwent a total of 60 anesthetic procedures. Intraosseous and conventional oral anesthesia caused discomfort during administration in 46.3% and 32.1% of the patients, respectively. The latency was 7.1±2.23 minutes for the conventional technique and 0.48±0.32 for intraosseous anesthesia – the difference being statistically significant. The depth of the anesthetic effect was sufficient to allow the patients to tolerate the dental treatments. The duration of the anesthetic effect in soft tissues was 199.3 minutes with the conventional technique versus only 1.6 minutes with intraosseous anesthesia – the difference between the two techniques being statistically significant. Most of the patients (69.7%) preferred intraosseous anesthesia. Conclusions: The described intraosseous anesthetic system is effective, with a much shorter latency than the conventional technique, sufficient duration of anesthesia to perform the required dental treatments, and with a much lesser soft tissue anesthetic effect. Most of the patients preferred intraosseous anesthesia. Key words:Anesthesia, intraosseous, oral anesthesia, infiltrating, mandibular block, Quicksleeper®. PMID:22143722

Blood cell mRNAs and microRNAs: optimized protocols for extraction and preservation.

PubMed

Eikmans, Michael; Rekers, Niels V; Anholts, Jacqueline D H; Heidt, Sebastiaan; Claas, Frans H J

2013-03-14

Assessing messenger RNA (mRNA) and microRNA levels in peripheral blood cells may complement conventional parameters in clinical practice. Working with small, precious samples requires optimal RNA yields and minimal RNA degradation. Several procedures for RNA extraction and complementary DNA (cDNA) synthesis were compared for their efficiency. The effect on RNA quality of freeze-thawing peripheral blood cells and storage in preserving reagents was investigated. In terms of RNA yield and convenience, quality quantitative polymerase chain reaction signals per nanogram of total RNA and using NucleoSpin and mirVana columns is preferable. The SuperScript III protocol results in the highest cDNA yields. During conventional procedures of storing peripheral blood cells at -180°C and thawing them thereafter, RNA integrity is maintained. TRIzol preserves RNA in cells stored at -20°C. Detection of mRNA levels significantly decreases in degraded RNA samples, whereas microRNA molecules remain relatively stable. When standardized to reference targets, mRNA transcripts and microRNAs can be reliably quantified in moderately degraded (quality index 4-7) and severely degraded (quality index <4) RNA samples, respectively. We describe a strategy for obtaining high-quality and quantity RNA from fresh and stored cells from blood. The results serve as a guideline for sensitive mRNA and microRNA expression assessment in clinical material.

Determination of different recreational drugs in sweat by headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME GC/MS): Application to drugged drivers.

PubMed

Gentili, Stefano; Mortali, Claudia; Mastrobattista, Luisa; Berretta, Paolo; Zaami, Simona

2016-09-10

A procedure based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography/mass spectrometry (GC/MS) has been developed for the determination of most commonly used drugs of abuse in sweat of drivers stopped during roadside controls. DrugWipe 5A sweat screening device was used to collect sweat by a specific pad rubbed gently over forehead skin surface. The procedure involved an acid hydrolysis, a HS-SPME extraction for drugs of abuse but Δ(9)-tetrahydrocannabinol, which was directly extracted in alkaline medium HS-SPME conditions, a GC separation of analytes by a capillary column and MS detection by electron impact ionisation. The method was linear from the limit of quantification (LOQ) to 50ng drug per pad (r(2)≥0.99), with an intra- and inter-assay precision and accuracy always less than 15% and an analytical recovery between 95.1% and 102.8%, depending on the considered analyte. Using the validated method, sweat from 60 apparently intoxicated drivers were found positive to one or more drugs of abuse, showing sweat patches testing as a viable economic and simple alternative to conventional (blood and/or urine) and non conventional (oral fluid) testing of drugs of abuse in drugged drivers. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of ionic liquids based enzyme-assisted extraction of chlorogenic acid from Eucommia ulmoides leaves.

PubMed

Liu, Tingting; Sui, Xiaoyu; Li, Li; Zhang, Jie; Liang, Xin; Li, Wenjing; Zhang, Honglian; Fu, Shuang

2016-01-15

A new approach for ionic liquid based enzyme-assisted extraction (ILEAE) of chlorogenic acid (CGA) from Eucommia ulmoides is presented in which enzyme pretreatment was used in ionic liquids aqueous media to enhance extraction yield. For this purpose, the solubility of CGA and the activity of cellulase were investigated in eight 1-alkyl-3-methylimidazolium ionic liquids. Cellulase in 0.5 M [C6mim]Br aqueous solution was found to provide better performance in extraction. The factors of ILEAE procedures including extraction time, extraction phase pH, extraction temperatures and enzyme concentrations were investigated. Moreover, the novel developed approach offered advantages in term of yield and efficiency compared with other conventional extraction techniques. Scanning electronic microscopy of plant samples indicated that cellulase treated cell wall in ionic liquid solution was subjected to extract, which led to more efficient extraction by reducing mass transfer barrier. The proposed ILEAE method would develope a continuous process for enzyme-assisted extraction including enzyme incubation and solvent extraction process. In this research, we propose a novel view for enzyme-assisted extraction of plant active component, besides concentrating on enzyme facilitated cell wall degradation, focusing on improvement of bad permeability of ionic liquids solutions. Copyright © 2015 Elsevier B.V. All rights reserved.

Extended morphological processing: a practical method for automatic spot detection of biological markers from microscopic images.

PubMed

Kimori, Yoshitaka; Baba, Norio; Morone, Nobuhiro

2010-07-08

A reliable extraction technique for resolving multiple spots in light or electron microscopic images is essential in investigations of the spatial distribution and dynamics of specific proteins inside cells and tissues. Currently, automatic spot extraction and characterization in complex microscopic images poses many challenges to conventional image processing methods. A new method to extract closely located, small target spots from biological images is proposed. This method starts with a simple but practical operation based on the extended morphological top-hat transformation to subtract an uneven background. The core of our novel approach is the following: first, the original image is rotated in an arbitrary direction and each rotated image is opened with a single straight line-segment structuring element. Second, the opened images are unified and then subtracted from the original image. To evaluate these procedures, model images of simulated spots with closely located targets were created and the efficacy of our method was compared to that of conventional morphological filtering methods. The results showed the better performance of our method. The spots of real microscope images can be quantified to confirm that the method is applicable in a given practice. Our method achieved effective spot extraction under various image conditions, including aggregated target spots, poor signal-to-noise ratio, and large variations in the background intensity. Furthermore, it has no restrictions with respect to the shape of the extracted spots. The features of our method allow its broad application in biological and biomedical image information analysis.

Membrane protein extraction and purification using styrene-maleic acid (SMA) copolymer: effect of variations in polymer structure.

PubMed

Morrison, Kerrie A; Akram, Aneel; Mathews, Ashlyn; Khan, Zoeya A; Patel, Jaimin H; Zhou, Chumin; Hardy, David J; Moore-Kelly, Charles; Patel, Roshani; Odiba, Victor; Knowles, Tim J; Javed, Masood-Ul-Hassan; Chmel, Nikola P; Dafforn, Timothy R; Rothnie, Alice J

2016-12-01

The use of styrene-maleic acid (SMA) copolymers to extract and purify transmembrane proteins, while retaining their native bilayer environment, overcomes many of the disadvantages associated with conventional detergent-based procedures. This approach has huge potential for the future of membrane protein structural and functional studies. In this investigation, we have systematically tested a range of commercially available SMA polymers, varying in both the ratio of styrene and maleic acid and in total size, for the ability to extract, purify and stabilise transmembrane proteins. Three different membrane proteins (BmrA, LeuT and ZipA), which vary in size and shape, were used. Our results show that several polymers, can be used to extract membrane proteins, comparably to conventional detergents. A styrene:maleic acid ratio of either 2:1 or 3:1, combined with a relatively small average molecular mass (7.5-10 kDa), is optimal for membrane extraction, and this appears to be independent of the protein size, shape or expression system. A subset of polymers were taken forward for purification, functional and stability tests. Following a one-step affinity purification, SMA 2000 was found to be the best choice for yield, purity and function. However, the other polymers offer subtle differences in size and sensitivity to divalent cations that may be useful for a variety of downstream applications. © 2016 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

Use of partial dissolution techniques in geochemical exploration

USGS Publications Warehouse

Chao, T.T.

1984-01-01

Application of partial dissolution techniques to geochemical exploration has advanced from an early empirical approach to an approach based on sound geochemical principles. This advance assures a prominent future position for the use of these techniques in geochemical exploration for concealed mineral deposits. Partial dissolution techniques are classified as single dissolution or sequential multiple dissolution depending on the number of steps taken in the procedure, or as "nonselective" extraction and as "selective" extraction in terms of the relative specificity of the extraction. The choice of dissolution techniques for use in geochemical exploration is dictated by the geology of the area, the type and degree of weathering, and the expected chemical forms of the ore and of the pathfinding elements. Case histories have illustrated many instances where partial dissolution techniques exhibit advantages over conventional methods of chemical analysis used in geochemical exploration. ?? 1984.

Comparison on extraction yield of sennoside A and sennoside B from senna (Cassia angustifolia) using conventional and non conventional extraction techniques and their quantification using a validated HPLC-PDA detection method.

PubMed

Dhanani, Tushar; Singh, Raghuraj; Reddy, Nagaraja; Trivedi, A; Kumar, Satyanshu

2017-05-01

Senna is an important medicinal plant and is used in many Ayurvedic formulations. Dianthraquinone glucosides are the main bioactive phytochemicals present in leaves and pods of senna. The extraction efficiency in terms of yield and composition of the extract of senna prepared using both conventional (cold percolation at room temperature and refluxing) and non conventional (ultrasound and microwave assisted solvent extraction as well as supercritical fluid extraction) techniques were compared in the present study. Also a rapid reverse phase HPLC-PDA detection method was developed and validated for the simultaneous determination of sennoside A and sennoside B in the different extracts of senna leaves. Ultrasound and microwave assisted solvent extraction techniques were more effective in terms of yield and composition of the extracts compared to cold percolation at room temperature and refluxing methods of extraction.

Differential enumeration of subpopulations in concentrated frozen and lyophilized cultures of Lactobacillus delbrueckii ssp. bulgaricus.

PubMed

Shao, Yuyu; Wang, Zhaoxia; Bao, Qiuhua; Zhang, Heping

2017-11-01

Differential enumeration of subpopulations in concentrated frozen and lyophilized cultures of Lactobacillus delbrueckii ssp. bulgaricus ND02 derived from 2 propagation procedures was determined. The subpopulations consisted of 3 categories (physiological states): viable cells capable of forming colonies on agar plates (VC+), viable cells incapable of forming colonies on agar plates (VC-), widely referred to as viable but nonculturable (VBNC) cells, and nonviable or dead cells (NVC). Counts of VC+ were recorded using a conventional plate count procedure. A fluorescent vital staining procedure that discriminates between viable (VC+ and VC-) and NVC cells was used to determine the number of viable and nonviable cells. Both propagation procedures had 2 variables: in procedure (P)1, the propagation medium was rich in yeast extract (4.0%) and the pH was maintained at 5.7; in P2, the medium was devoid of yeast extract and the pH was maintained at 5.1. The results showed that post-propagation operations-concentration of cells by centrifugation and subsequent freezing or lyophilization of cell concentrate-induced different degrees of transience from VC+ to VC- states in cells derived from P1 and P2. Compared with cells derived from P2, cells from P1 were more labile to stress associated with centrifugation, freezing, and lyophilization, as revealed by differential counting. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Extraction of SelectSecure leads compared to conventional pacing leads in patients with congenital heart disease and congenital atrioventricular block.

PubMed

Shepherd, Emma; Stuart, Graham; Martin, Rob; Walsh, Mark A

2015-06-01

SelectSecure™ pacing leads (Medtronic Inc) are increasingly being used in pediatric patients and adults with structural congenital heart disease. The 4Fr lead is ideal for patients who may require lifelong pacing and can be advantageous for patients with complex anatomy. The purpose of this study was to compare the extraction of SelectSecure leads with conventional (stylette-driven) pacing leads in patients with structural congenital heart disease and congenital atrioventricular block. The data on lead extractions from pediatric and adult congenital heart disease (ACHD) patients from August 2004 to July 2014 at Bristol Royal Hospital for Children and the Bristol Heart Institute were reviewed. Multivariable regression analysis was used to determine whether conventional pacing leads were associated with a more difficult extraction process. A total of 57 patients underwent pacemaker lead extractions (22 SelectSecure, 35 conventional). No deaths occurred. Mean age at the time of extraction was 17.6 ± 10.5 years, mean weight was 47 ± 18 kg, and mean lead age was 5.6 ± 2.6 years (range 1-11 years). Complex extraction (partial extraction/femoral extraction) was more common in patients with conventional pacing leads at univariate (P < .01) and multivariate (P = .04) levels. Lead age was also a significant predictor of complex extraction (P < .01). SelectSecure leads can be successfully extracted using techniques that are used for conventional pacing leads. They are less likely to be partially extracted and are less likely to require extraction using a femoral approach compared with conventional pacing leads. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

The detection and analysis of point processes in biological signals

NASA Technical Reports Server (NTRS)

Anderson, D. J.; Correia, M. J.

1977-01-01

A pragmatic approach to the detection and analysis of discrete events in biomedical signals is taken. Examples from both clinical and basic research are provided. Introductory sections discuss not only discrete events which are easily extracted from recordings by conventional threshold detectors but also events embedded in other information carrying signals. The primary considerations are factors governing event-time resolution and the effects limits to this resolution have on the subsequent analysis of the underlying process. The analysis portion describes tests for qualifying the records as stationary point processes and procedures for providing meaningful information about the biological signals under investigation. All of these procedures are designed to be implemented on laboratory computers of modest computational capacity.

Variation in levels of some leaf enzymes.

PubMed

Downton, J; Slatyer, R O

1971-03-01

Several procedures were compared for efficiency in the extraction of certain leaf enzymes (phosphoenolpyruvate carboxylase, ribulose 1,5-diphosphate carboxylase and malate dehydrogenase) in Atriplex hastata (a "C3" species exhibiting conventional photosynthetic metabolism), and in A. spongiosa (a "C4" species in which the initial photosynthetic products are C4 dicarboxylic acids). Glycolate oxidase was also assayed in some cases, and Atriplex nummularia and Sorghum bicolor were also used as test material. A simple procedure, involving a mortar and pestle grind with carborundum added to the grinding mixture, was found to be as effective as glass bead grind procedures. In addition, it was more rapid and showed less variability with different operations.Using the carborundum grind procedure, sources of variability in enzyme activity in apparently uniform leaves were compared, as were effects of time of day, leaf age and storage procedure. In general, if apparently uniform leaves could be selected, variability in levels of enzyme activity appeared to be relatively small, not exceeding about 12%. Time of day also appeared to be relatively unimportant for the enzymes examined. However, the ontogentic status of the plant was found to be an important source of variability. Leaf age was also a major source of variability where the activity was expressed on a fresh weight basis, but specific activity (i.e. activity expressed on a protein basis) was relatively constant, at least with the range of species and leaf ages examined here.Storage of fresh samples in liquid nitrogen for 24 h, prior to extraction and assay, led to only a small reduction in activity, but substantial changes occurred if storage was in dry ice or in ice and also where extracts were stored in a deep freeze.

Antioxidant Capacity Determination in Plants and Plant-Derived Products: A Review

PubMed Central

Pop, Aneta; Cimpeanu, Carmen; Predoi, Gabriel

2016-01-01

The present paper aims at reviewing and commenting on the analytical methods applied to antioxidant and antioxidant capacity assessment in plant-derived products. Aspects related to oxidative stress, reactive oxidative species' influence on key biomolecules, and antioxidant benefits and modalities of action are discussed. Also, the oxidant-antioxidant balance is critically discussed. The conventional and nonconventional extraction procedures applied prior to analysis are also presented, as the extraction step is of pivotal importance for isolation and concentration of the compound(s) of interest before analysis. Then, the chromatographic, spectrometric, and electrochemical methods for antioxidant and antioxidant capacity determination in plant-derived products are detailed with respect to their principles, characteristics, and specific applications. Peculiarities related to the matrix characteristics and other factors influencing the method's performances are discussed. Health benefits of plants and derived products are described, as indicated in the original source. Finally, critical and conclusive aspects are given when it comes to the choice of a particular extraction procedure and detection method, which should consider the nature of the sample, prevalent antioxidant/antioxidant class, and the mechanism underlying each technique. Advantages and disadvantages are discussed for each method. PMID:28044094

Subcritical water extraction of organic matter from sedimentary rocks.

PubMed

Luong, Duy; Sephton, Mark A; Watson, Jonathan S

2015-06-16

Subcritical water extraction of organic matter containing sedimentary rocks at 300°C and 1500 psi produces extracts comparable to conventional solvent extraction. Subcritical water extraction of previously solvent extracted samples confirms that high molecular weight organic matter (kerogen) degradation is not occurring and that only low molecular weight organic matter (free compounds) are being accessed in analogy to solvent extraction procedures. The sedimentary rocks chosen for extraction span the classic geochemical organic matter types. A type I organic matter-containing sedimentary rock produces n-alkanes and isoprenoidal hydrocarbons at 300°C and 1500 psi that indicate an algal source for the organic matter. Extraction of a rock containing type II organic matter at the same temperature and pressure produces aliphatic hydrocarbons but also aromatic compounds reflecting the increased contributions from terrestrial organic matter in this sample. A type III organic matter-containing sample produces a range of non-polar and polar compounds including polycyclic aromatic hydrocarbons and oxygenated aromatic compounds at 300°C and 1500 psi reflecting a dominantly terrestrial origin for the organic materials. Although extraction at 300°C and 1500 psi produces extracts that are comparable to solvent extraction, lower temperature steps display differences related to organic solubility. The type I organic matter produces no products below 300°C and 1500 psi, reflecting its dominantly aliphatic character, while type II and type III organic matter contribute some polar components to the lower temperature steps, reflecting the chemical heterogeneity of their organic inventory. The separation of polar and non-polar organic compounds by using different temperatures provides the potential for selective extraction that may obviate the need for subsequent preparative chromatography steps. Our results indicate that subcritical water extraction can act as a suitable replacement for conventional solvent extraction of sedimentary rocks, but can also be used for any organic matter containing mineral matrix, including soils and recent sediments, and has the added benefit of tailored extraction for analytes of specific polarities. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Signal processing to evaluate parameters affecting SPE for multi-residue analysis of personal care products.

PubMed

Pietrogrande, Maria Chiara; Basaglia, Giulia; Dondi, Francesco

2009-05-01

This paper discusses the development of a comprehensive method for the simultaneous analysis of personal care products (PCPs) based on SPE and GC-MS. The method was developed on 29 target compounds to represent PCPs belonging to different chemical classes: surfactants in detergents (alkyl benzenes), fragrances in cosmetics (nitro and polycyclic musks), antioxidants and preservatives (phenols), plasticizers (phthalates) displaying a wide range of volatility, polarity, water solubility. In addition to the conventional C(18) stationary phase, a surface modified styrene divinylbenzene polymeric phase (Strata X SPE cartridge) has been investigated as suitable for the simultaneous extraction of several PCPs with polar and non-polar characteristics. For both sorbents different solvent compositions and eluting conditions were tested and compared in order to achieve high extraction efficiency for as many sample components as possible. Comparison of the behavior of the two cartridges reveals that, overall, Strata-X provides better efficiency with extraction recovery higher than 70% for most of the PCPs investigated. The best results were obtained under the following operative conditions: an evaporation temperature of 40 degrees C, elution on Strata-X cartridge using a volume of 15 mL of ethyl acetate (EA) as solvent and operating with slow flow rate (-10 KPa). In addition to the conventional method based on peak integration, a chemometric approach based on the computation of the experimental autocovariance function (EACVF(tot)) was applied to the complex GC-MS signal: the percentage recovery and information on peak abundance distribution can be evaluated for each procedure step. The PC-based signal processing proved very helpful in assisting the development of the analytical procedure, since it saves labor and time and increases result reliability in handling GC complex signals.

Coniferous forest classification and inventory using Landsat and digital terrain data

NASA Technical Reports Server (NTRS)

Franklin, J.; Logan, T. L.; Woodcock, C. E.; Strahler, A. H.

1986-01-01

Machine-processing techniques were used in a Forest Classification and Inventory System (FOCIS) procedure to extract and process tonal, textural, and terrain information from registered Landsat multispectral and digital terrain data. Using FOCIS as a basis for stratified sampling, the softwood timber volumes of the Klamath National Forest and Eldorado National Forest were estimated within standard errors of 4.8 and 4.0 percent, respectively. The accuracy of these large-area inventories is comparable to the accuracy yielded by use of conventional timber inventory methods, but, because of automation, the FOCIS inventories are more rapid (9-12 months compared to 2-3 years for conventional manual photointerpretation, map compilation and drafting, field sampling, and data processing) and are less costly.

A Rapid and Accurate Extraction Procedure for Analysing Free Amino Acids in Meat Samples by GC-MS

PubMed Central

Barroso, Miguel A.; Ruiz, Jorge; Antequera, Teresa

2015-01-01

This study evaluated the use of a mixer mill as the homogenization tool for the extraction of free amino acids in meat samples, with the main goal of analyzing a large number of samples in the shortest time and minimizing sample amount and solvent volume. Ground samples (0.2 g) were mixed with 1.5 mL HCl 0.1 M and homogenized in the mixer mill. The final biphasic system was separated by centrifugation. The supernatant was deproteinized, derivatized and analyzed by gas chromatography. This procedure showed a high extracting ability, especially in samples with high free amino acid content (recovery = 88.73–104.94%). It also showed a low limit of detection and quantification (3.8 · 10−4–6.6 · 10−4  μg μL−1 and 1.3 · 10−3–2.2 · 10−2  μg μL−1, resp.) for most amino acids, an adequate precision (2.15–20.15% for run-to-run), and a linear response for all amino acids (R 2 = 0.741–0.998) in the range of 1–100 µg mL−1. Moreover, it takes less time and requires lower amount of sample and solvent than conventional techniques. Thus, this is a cost and time efficient tool for homogenizing in the extraction procedure of free amino acids from meat samples, being an adequate option for routine analysis. PMID:25873963

Supercritical Carbon Dioxide Extraction of Carotenoids from Pumpkin (Cucurbita spp.): A Review

PubMed Central

Durante, Miriana; Lenucci, Marcello Salvatore; Mita, Giovanni

2014-01-01

Carotenoids are well known for their nutritional properties and health promoting effects representing attractive ingredients to develop innovative functional foods, nutraceutical and pharmaceutical preparations. Pumpkin (Cucurbita spp.) flesh has an intense yellow/orange color owing to the high level of carotenoids, mainly α-carotene, β-carotene, β-cryptoxanthin, lutein and zeaxanthin. There is considerable interest in extracting carotenoids and other bioactives from pumpkin flesh. Extraction procedures able to preserve nutritional and pharmacological properties of carotenoids are essential. Conventional extraction methods, such as organic solvent extraction (CSE), have been used to extract carotenoids from plant material for a long time. In recent years, supercritical carbon dioxide (SC-CO2) extraction has received a great deal of attention because it is a green technology suitable for the extraction of lipophylic molecules and is able to give extracts of high quality and totally free from potentially toxic chemical solvents. Here, we review the results obtained so far on SC-CO2 extraction efficiency and quali-quantitative composition of carotenoids from pumpkin flesh. In particular, we consider the effects of (1) dehydration pre-treatments; (2) extraction parameters (temperature and pressure); the use of water, ethanol and olive oil singularly or in combination as entrainers or pumpkin seeds as co-matrix. PMID:24756094

Supercritical carbon dioxide extraction of carotenoids from pumpkin (Cucurbita spp.): a review.

PubMed

Durante, Miriana; Lenucci, Marcello Salvatore; Mita, Giovanni

2014-04-21

Carotenoids are well known for their nutritional properties and health promoting effects representing attractive ingredients to develop innovative functional foods, nutraceutical and pharmaceutical preparations. Pumpkin (Cucurbita spp.) flesh has an intense yellow/orange color owing to the high level of carotenoids, mainly α-carotene, β-carotene, β-cryptoxanthin, lutein and zeaxanthin. There is considerable interest in extracting carotenoids and other bioactives from pumpkin flesh. Extraction procedures able to preserve nutritional and pharmacological properties of carotenoids are essential. Conventional extraction methods, such as organic solvent extraction (CSE), have been used to extract carotenoids from plant material for a long time. In recent years, supercritical carbon dioxide (SC-CO2) extraction has received a great deal of attention because it is a green technology suitable for the extraction of lipophylic molecules and is able to give extracts of high quality and totally free from potentially toxic chemical solvents. Here, we review the results obtained so far on SC-CO2 extraction efficiency and quali-quantitative composition of carotenoids from pumpkin flesh. In particular, we consider the effects of (1) dehydration pre-treatments; (2) extraction parameters (temperature and pressure); the use of water, ethanol and olive oil singularly or in combination as entrainers or pumpkin seeds as co-matrix.

Green extraction of grape skin phenolics by using deep eutectic solvents.

PubMed

Cvjetko Bubalo, Marina; Ćurko, Natka; Tomašević, Marina; Kovačević Ganić, Karin; Radojčić Redovniković, Ivana

2016-06-01

Conventional extraction techniques for plant phenolics are usually associated with high organic solvent consumption and long extraction times. In order to establish an environmentally friendly extraction method for grape skin phenolics, deep eutectic solvents (DES) as a green alternative to conventional solvents coupled with highly efficient microwave-assisted and ultrasound-assisted extraction methods (MAE and UAE, respectively) have been considered. Initially, screening of five different DES for proposed extraction was performed and choline chloride-based DES containing oxalic acid as a hydrogen bond donor with 25% of water was selected as the most promising one, resulting in more effective extraction of grape skin phenolic compounds compared to conventional solvents. Additionally, in our study, UAE proved to be the best extraction method with extraction efficiency superior to both MAE and conventional extraction method. The knowledge acquired in this study will contribute to further DES implementation in extraction of biologically active compounds from various plant sources. Copyright © 2016 Elsevier Ltd. All rights reserved.

Minimally invasive esthetic ridge preservation with growth-factor enhanced bone matrix.

PubMed

Nevins, Marc L; Said, Sherif

2017-12-28

Extraction socket preservation procedures are critical to successful esthetic implant therapy. Conventional surgical approaches are technique sensitive and often result in alteration of the soft tissue architecture, which then requires additional corrective surgical procedures. This case series report presents the ability of flapless surgical techniques combined with a growth factor-enhanced bone matrix to provide esthetic ridge preservation at the time of extraction for compromised sockets. When considering esthetic dental implant therapy, preservation, or further enhancement of the available tissue support at the time of tooth extraction may provide an improved esthetic outcome with reduced postoperative sequelae and decreased treatment duration. Advances in minimally invasive surgical techniques combined with recombinant growth factor technology offer an alternative for bone reconstruction while maintaining the gingival architecture for enhanced esthetic outcome. The combination of freeze-dried bone allograft (FDBA) and rhPDGF-BB (platelet-derived growth factor-BB) provides a growth-factor enhanced matrix to induce bone and soft tissue healing. The use of a growth-factor enhanced matrix is an option for minimally invasive ridge preservation procedures for sites with advanced bone loss. Further studies including randomized clinical trials are needed to better understand the extent and limits of these procedures. The use of minimally invasive techniques with growth factors for esthetic ridge preservation reduces patient morbidity associated with more invasive approaches and increases the predictability for enhanced patient outcomes. By reducing the need for autogenous bone grafts the use of this technology is favorable for patient acceptance and ease of treatment process for esthetic dental implant therapy. © 2017 Wiley Periodicals, Inc.

Optimization of Ultrasound Assisted Extraction of Functional Ingredients from Stevia Rebaudiana Bertoni Leaves

NASA Astrophysics Data System (ADS)

Šic Žlabur, Jana; Voća, Sandra; Dobričević, Nadica; Brnčić, Mladen; Dujmić, Filip; Rimac Brnčić, Suzana

2015-04-01

The aim of the present study was to reveal an effective extraction procedure for maximization of the yield of steviol glycosides and total phenolic compounds as well as antioxidant activity in stevia extracts. Ultrasound assisted extraction was compared with conventional solvent extraction. The examined solvents were water (100°C/24 h) and 70% ethanol (at 70°C for 30 min). Qualitative and quantitative analyses of steviol glycosides in the extracts obtained were performed using high performance liquid chromatography. Total phenolic compounds, flavonoids, and radical scavenging capacity by 2, 2-azino-di-3-ethylbenzothialozine- sulphonic acid) assay were also determined. The highest content of steviol glycosides, total phenolic compounds, and flavonoids in stevia extracts were obtained when ultrasound assisted extraction was used. The antioxidant activity of the extracts was correlated with the total amount of phenolic compounds. The results indicated that the examined sonication parameters represented as the probe diameter (7 and 22 mm) and treatment time (2, 4, 6, 8, and 10 min) significantly contributed to the yield of steviol glycosides, total phenolic compounds, and flavonoids. The optimum conditions for the maximum yield of steviol glycosides, total phenolic compounds, and flavonoids were as follows: extraction time 10 min, probe diameter 22 mm, and temperature 81.2°C.

On-matrix derivatization extraction of chemical weapons convention relevant alcohols from soil.

PubMed

Chinthakindi, Sridhar; Purohit, Ajay; Singh, Varoon; Dubey, D K; Pardasani, Deepak

2013-10-11

Present study deals with the on-matrix derivatization-extraction of aminoalcohols and thiodiglycols, which are important precursors and/or degradation products of VX analogues and vesicants class of chemical warfare agents (CWAs). The method involved hexamethyldisilazane (HMDS) mediated in situ silylation of analytes on the soil. Subsequent extraction and gas chromatography-mass spectrometry analysis of derivatized analytes offered better recoveries in comparison to the procedure recommended by the Organization for the Prohibition of Chemical Weapons (OPCW). Various experimental conditions such as extraction solvent, reagent and catalyst amount, reaction time and temperature were optimized. Best recoveries of analytes ranging from 45% to 103% were obtained with DCM solvent containing 5%, v/v HMDS and 0.01%, w/v iodine as catalyst. The limits of detection (LOD) and limit of quantification (LOQ) with selected analytes ranged from 8 to 277 and 21 to 665ngmL(-1), respectively, in selected ion monitoring mode. Copyright © 2013 Elsevier B.V. All rights reserved.

Non-stationary component extraction in noisy multicomponent signal using polynomial chirping Fourier transform.

PubMed

Lu, Wenlong; Xie, Junwei; Wang, Heming; Sheng, Chuan

2016-01-01

Inspired by track-before-detection technology in radar, a novel time-frequency transform, namely polynomial chirping Fourier transform (PCFT), is exploited to extract components from noisy multicomponent signal. The PCFT combines advantages of Fourier transform and polynomial chirplet transform to accumulate component energy along a polynomial chirping curve in the time-frequency plane. The particle swarm optimization algorithm is employed to search optimal polynomial parameters with which the PCFT will achieve a most concentrated energy ridge in the time-frequency plane for the target component. The component can be well separated in the polynomial chirping Fourier domain with a narrow-band filter and then reconstructed by inverse PCFT. Furthermore, an iterative procedure, involving parameter estimation, PCFT, filtering and recovery, is introduced to extract components from a noisy multicomponent signal successively. The Simulations and experiments show that the proposed method has better performance in component extraction from noisy multicomponent signal as well as provides more time-frequency details about the analyzed signal than conventional methods.

A comparison study on a sulfonated graphene-polyaniline nanocomposite coated fiber for analysis of nicotine in solid samples through the traditional and vacuum-assisted HS-SPME.

PubMed

Ghiasvand, Alireza; Koonani, Samira; Yazdankhah, Fatemeh; Farhadi, Saeid

2018-02-05

A simple, rapid, and reliable headspace solid-phase microextraction (HS-SPME) procedure, reinforced by applying vacuum in the extraction vial, was developed. It was applied for the extraction of nicotine in solid samples prior to determination by gas chromatography-flame ionization detection (GC-FID). First, the surface of a narrow stainless steel wire was made porous and adhesive by platinization to obtain a durable, higher surface area, and resistant fiber. Then, a thin film of sulfonated graphene/polyaniline (Sulf-G/PANI) nanocomposite was synthesized and simultaneously coated on the platinized fiber using the electrophoretic deposition (EPD) method. It was demonstrated that the extraction efficiency remarkably increased by applying the reduced-pressure condition in the extraction vial. To evaluate the conventional HS-SPME and vacuum-assisted HS-SPME (VA-HS-SPME) platforms, all experimental parameters affecting the extraction efficiency including desorption time and temperature, extraction time and temperature and moisture content of sample matrix were optimized. The highest extraction efficiency was obtained at 60°C, 10min (extraction temperature and time) and 280°C, 2min (desorption condition), for VA-HS-SPME strategy, while for conventional HS-SPME the extraction and desorption conditions found to be 100°C, 30min and 280°C, 2min, respectively. The Sulf-G/PANI coated fiber showed high thermal stability, good chemical/mechanical resistance, and long lifetime. For analysis of nicotine in solid samples using VA-HS-SPME-GC-FID, linear dynamic range (LDR) was 0.01-30μgg -1 (R 2 =0.996), the relative standard deviation (RSD%, n=6), for analyses of 1μgg -1 nicotine was calculated 3.4% and limit of detection (LOD) found to be 0.002μgg -1 . The VA-HS-SPME-GC-FID strategy was successfully carried out for quantitation of nicotine in hair and tobacco real samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of the potential use of hybrid LC-MS/MS for active drug quantification applying the 'free analyte QC concept'.

PubMed

Jordan, Gregor; Onami, Ichio; Heinrich, Julia; Staack, Roland F

2017-11-01

Assessment of active drug exposure of biologics may be crucial for drug development. Typically, ligand-binding assay methods are used to provide free/active drug concentrations. To what extent hybrid LC-MS/MS procedures enable correct 'active' drug quantification is currently under consideration. Experimental & results: The relevance of appropriate extraction condition was evaluated by a hybrid target capture immuno-affinity LC-MS/MS method using total and free/active quality controls (QCs). The rapid extraction (10 min) provided correct results, whereas overnight incubation resulted in significant overestimation of the free/active drug (monclonal antibody) concentration. Conventional total QCs were inappropriate to determine optimal method conditions in contrast to free/active QCs. The 'free/active analyte QC concept' enables development of appropriate extraction conditions for correct active drug quantification by hybrid LC-MS/MS.

Overestimation of organic phosphorus in wetland soils by alkaline extraction and molybdate colorimetry.

PubMed

Turner, Benjamin L; Newman, Susan; Reddy, K Ramesh

2006-05-15

Accurate information on the chemical nature of soil phosphorus is essential for understanding its bioavailability and fate in wetland ecosystems. Solution phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy was used to assess the conventional colorimetric procedure for phosphorus speciation in alkaline extracts of organic soils from the Florida Everglades. Molybdate colorimetry markedly overestimated organic phosphorus by between 30 and 54% compared to NMR spectroscopy. This was due in large part to the association of inorganic phosphate with organic matter, although the error was exacerbated in some samples by the presence of pyrophosphate, an inorganic polyphosphate that is not detected by colorimetry. The results have important implications for our understanding of phosphorus biogeochemistry in wetlands and suggest that alkaline extraction and solution 31p NMR spectroscopy is the only accurate method for quantifying organic phosphorus in wetland soils.

Comparison of different strategies for soybean antioxidant extraction.

PubMed

Chung, Hyun; Ji, Xiangming; Canning, Corene; Sun, Shi; Zhou, Kequan

2010-04-14

Three extraction strategies including Soxhlet extraction, conventional solid-liquid extraction, and ultrasonic-assisted extraction (UAE) were compared for their efficiency to extract phenolic antioxidants from Virginia-grown soybean seeds. Five extraction solvents were evaluated in UAE and the conventional extraction. The soybean extracts were compared for their total phenolic contents (TPC), oxygen radical absorbance capacity (ORAC), and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) scavenging activities. The results showed that UAE improved the extraction of soybean phenolic compounds by >54% compared to the conventional and Soxhlet extractions. Among the tested solvents, 50% acetone was the most efficient for extracting soybean phenolic compounds. There was no significant correlation between the TPC and antioxidant activities of the soybean extracts. The extracts prepared by 70% ethanol had the highest ORAC values. Overall, UAE with 50% acetone or 70% ethanol is recommended for extracting soybean antioxidants on the basis of the TPC and ORAC results.

Automated extraction of natural drainage density patterns for the conterminous United States through high performance computing

USGS Publications Warehouse

Stanislawski, Larry V.; Falgout, Jeff T.; Buttenfield, Barbara P.

2015-01-01

Hydrographic networks form an important data foundation for cartographic base mapping and for hydrologic analysis. Drainage density patterns for these networks can be derived to characterize local landscape, bedrock and climate conditions, and further inform hydrologic and geomorphological analysis by indicating areas where too few headwater channels have been extracted. But natural drainage density patterns are not consistently available in existing hydrographic data for the United States because compilation and capture criteria historically varied, along with climate, during the period of data collection over the various terrain types throughout the country. This paper demonstrates an automated workflow that is being tested in a high-performance computing environment by the U.S. Geological Survey (USGS) to map natural drainage density patterns at the 1:24,000-scale (24K) for the conterminous United States. Hydrographic network drainage patterns may be extracted from elevation data to guide corrections for existing hydrographic network data. The paper describes three stages in this workflow including data pre-processing, natural channel extraction, and generation of drainage density patterns from extracted channels. The workflow is concurrently implemented by executing procedures on multiple subbasin watersheds within the U.S. National Hydrography Dataset (NHD). Pre-processing defines parameters that are needed for the extraction process. Extraction proceeds in standard fashion: filling sinks, developing flow direction and weighted flow accumulation rasters. Drainage channels with assigned Strahler stream order are extracted within a subbasin and simplified. Drainage density patterns are then estimated with 100-meter resolution and subsequently smoothed with a low-pass filter. The extraction process is found to be of better quality in higher slope terrains. Concurrent processing through the high performance computing environment is shown to facilitate and refine the choice of drainage density extraction parameters and more readily improve extraction procedures than conventional processing.

DNA extraction on bio-chip: history and preeminence over conventional and solid-phase extraction methods.

PubMed

Ayoib, Adilah; Hashim, Uda; Gopinath, Subash C B; Md Arshad, M K

2017-11-01

This review covers a developmental progression on early to modern taxonomy at cellular level following the advent of electron microscopy and the advancement in deoxyribonucleic acid (DNA) extraction for expatiation of biological classification at DNA level. Here, we discuss the fundamental values of conventional chemical methods of DNA extraction using liquid/liquid extraction (LLE) followed by development of solid-phase extraction (SPE) methods, as well as recent advances in microfluidics device-based system for DNA extraction on-chip. We also discuss the importance of DNA extraction as well as the advantages over conventional chemical methods, and how Lab-on-a-Chip (LOC) system plays a crucial role for the future achievements.

Optimisation of phenolics recovery from Vitex agnus-castus Linn. leaves by high-pressure and temperature extraction.

PubMed

Lataoui, Mohammed; Seffen, Mongi; Aliakbarian, Bahar; Casazza, Alessandro Alberto; Converti, Attilio; Perego, Patrizia

2014-01-01

To optimise recovery of phenolics from Vitex agnus-castus Linn., a non-conventional high-pressure (2-24 bar) and temperature (100-180°C) extraction method was used under nitrogen atmosphere with methanol as a solvent. Optimal temperature was between 100 and 140°C, and optimal extraction time was about one half that of conventional solid/liquid extraction at room temperature. Final yields of total polyphenols, total flavonoids, o-diphenols and anthocyanins extraction were 2.0, 3.0, 2.5 and 11-fold those obtained by conventional extraction.

Fully 3D-Printed Preconcentrator for Selective Extraction of Trace Elements in Seawater.

PubMed

Su, Cheng-Kuan; Peng, Pei-Jin; Sun, Yuh-Chang

2015-07-07

In this study, we used a stereolithographic 3D printing technique and polyacrylate polymers to manufacture a solid phase extraction preconcentrator for the selective extraction of trace elements and the removal of unwanted salt matrices, enabling accurate and rapid analyses of trace elements in seawater samples when combined with a quadrupole-based inductively coupled plasma mass spectrometer. To maximize the extraction efficiency, we evaluated the effect of filling the extraction channel with ordered cuboids to improve liquid mixing. Upon automation of the system and optimization of the method, the device allowed highly sensitive and interference-free determination of Mn, Ni, Zn, Cu, Cd, and Pb, with detection limits comparable with those of most conventional methods. The system's analytical reliability was further confirmed through analyses of reference materials and spike analyses of real seawater samples. This study suggests that 3D printing can be a powerful tool for building multilayer fluidic manipulation devices, simplifying the construction of complex experimental components, and facilitating the operation of sophisticated analytical procedures for most sample pretreatment applications.

Ultrasound-assisted extraction of water-soluble polysaccharides from the roots of valerian (Valeriana officinalis L.).

PubMed

Hromádková, Z; Ebringerová, A; Valachovic, P

2002-01-01

The insoluble plant residues, obtained after preparation of medicinal tinctures from the roots of valerian (Valeriana officinalis L.) by classical and ultrasound-assisted extraction with aqueous ethanol in a pilot plant, were subsequently treated with hot water to isolate the accessible polysaccharide cell wall components. At almost equal amounts of the hot-water extractable material, the yields of the recovered polysaccharides were lower in the ultrasonical experiment. This is due to the fact that a part of accessible polysaccharides were already solubilised by the aqueous ethanol and recoverable from the medicinal tincture. Therefore, the net yield of extracted polysaccharides was enhanced in the ultrasonical procedure. This fact as well as the sugar composition and structural features of the isolated polysaccharides suggest that ultrasonication have attacked the integrity of cell walls, released and degraded its most accessible polysaccharides (pectic polysaccharides and starch) and increased also the extractibility of its less accessible components--xylan, mannan and glucan. The water-soluble polysaccharide fractions from both the conventional and ultrasonical experiments exhibit significant immunostimulatory activities in mitogenic and comitogenic thymocyte tests.

A modified extraction and clean-up procedure for the detection and determination of parathion-methyl and chlorpyrifos residues in tea.

PubMed

Shanker, A; Sood, C; Kumar, V; Ravindranath, S D

2001-05-01

Recent advances in methodology and instrumentation have made possible the detection and determination of pesticides at microgram kg-1 (ppb) levels. The sensitivity of a method of analysis depends greatly on the efficient extraction of the pesticide and the subsequent clean-up of the extract. The extract from green tea leaves is a mixture of aroma components, polyphenols and caffeine. The preparation of made tea from green tea leaves adds to this complexity by concentrating these coextractives. Conventional clean-up techniques provide poor recoveries for parathion-methyl and chlorpyrifos from both green tea leaves and made tea. This arises from interference by caffeine during gas chromatography, as it has a similar retention time to the two pesticides and peaks overlap. A modification to the protocol based on a solvent partitioning process using dichloromethane and subsequent washing of the extracts with warm water removed the caffeine, and pigments were removed by column chromatography. Recoveries ranging from 80 to 90% were then obtained for both pesticides.

Antibacterial effect of roselle extracts (Hibiscus sabadariffa), sodium hypochlorite and acetic acid against multidrug-resistant Salmonella strains isolated from tomatoes.

PubMed

Gutiérrez-Alcántara, E J; Rangel-Vargas, E; Gómez-Aldapa, C A; Falfan-Cortes, R N; Rodríguez-Marín, M L; Godínez-Oviedo, A; Cortes-López, H; Castro-Rosas, J

2016-02-01

Antibiotic-resistant Salmonella strains were isolated from saladette and red round type tomatoes, and an analysis done of the antibacterial activity of roselle calyx extracts against any of the identified strains. One hundred saladette tomato samples and 100 red round tomato samples were collected from public markets. Each sample consisted of four whole tomatoes. Salmonella was isolated from the samples by conventional culture procedure. Susceptibility to 16 antibiotics was tested for the isolated Salmonella strains by standard test. The antibacterial effect of four roselle calyx extracts (water, methanol, acetone and ethyl acetate), sodium hypochlorite and acetic acid against antibiotic-resistant Salmonella isolates was evaluated on contaminated tomatoes. Twenty-four Salmonella strains were isolated from 12% of each tomato type. Identified Salmonella serotypes were Typhimurium and Typhi. All isolated strains exhibited resistance to at least three antibiotics and some to as many as 12. Over contaminated tomatoes, the roselle calyx extracts produced a greater reduction (2-2·6 log) in antibiotic-resistant Salmonella strain concentration than sodium hypochlorite and acetic acid. The presence of multidrug-resistant Salmonella in vegetables is a significant public health concern. Multidrug-resistant Salmonella strains were isolated from raw tomatoes purchased in public markets in Mexico and challenged with roselle Hibiscus sabdariffa calyx extracts, sodium hypochlorite and acetic acid. On tomatoes, the extracts caused a greater reduction in the concentration of antibiotic-resistant Salmonella strains than sodium hypochlorite and acetic acid. Roselle calyx extracts are a potentially useful addition to disinfection procedures of raw tomatoes in the field, processing plants, restaurants and homes. © 2015 The Society for Applied Microbiology.

Combination pulsed electric field with ethanol solvent for Nannochloropsis sp. extraction

NASA Astrophysics Data System (ADS)

Nafis, Ghazy Ammar; Mumpuni, Perwitasari Yekti; Indarto, Budiman, Arief

2015-12-01

Nowadays, energy is one of human basic needs. As the human population increased, energy consumption also increased. This condition causes energy depletion. In case of the situation, alternative energy is needed to replace existing energy. Microalgae is chosen to become one of renewable energy resource, especially biodiesel, because it contains high amount of lipid instead of other feedstock which usually used. Fortunately, Indonesia has large area of water and high intensity of sunlight so microalgae cultivation becomes easier. Nannochloropsis sp., one of microalgae species, becomes the main focus because of its high lipid content. Many ways to break the cell wall of microalgae so the lipid content inside the microalgae will be released, for example conventional extraction, ultrasonic wave extraction, pressing, and electrical method. The most effective way for extraction is electrical method such as pulsed electric field method (PEF). The principal work of this method is by draining the electrical current into parallel plate. Parallel plate will generate the electrical field to break microalgae cell wall and the lipid will be released. The aim of this work is to evaluate two-stage procedure for extraction of useful components from microalgae Nannochloropsis sp. The first stage of this procedure includes pre-treatment of microalgae by ethanol solvent extraction and the second stage applies the PEF extraction using a binary mixture of water and ethanol solvent. Ethanol is chosen as solvent because it's safer to be used and easier to be handled than other solvent. Some variables that used to study the most effective operation conditions are frequency and duty cycle for microalgae. The optimum condition based on this research are at frequency 1 Hz and duty cycle 13%.

Conventional and unconventional extraction methods applied to the plant, Thymus serpyllum L

NASA Astrophysics Data System (ADS)

Đukić, D.; Mašković, P.; Vesković Moračanin, S.; Kurćubić, V.; Milijašević, M.; Babić, J.

2017-09-01

This study deals with the application of two conventional and three non-conventional extraction approaches for isolation of bioactive compounds from the plant Thymus serpyllum L. The extracts obtained were tested regarding their chemical profile (content of phenolics, flavonoids, condensed tannins, gallotannins and anthocyanins) and antioxidant activities. Subcritical water extract of Thymus serpyllum L. generally had the highest concentrations of the chemical bioactive compounds examined and the best antioxidant properties.

Haemostasis in Oral Surgery with Blue-Violet Light.

PubMed

Veleska-Stevkoska, Daniela; Koneski, Filip

2018-04-15

The invasive dental procedures usually result in wounds accompanied by physiological bleeding. Even though the bleeding is easily manageable, it is still one of the major concerns of the patients and a reason for their subjective discomfort. Recently, a novel approach with light-emitting diode (LED) was introduced to control the bleeding. This study aims to examine the effectiveness of the irradiation with blue-violet light LEDs on the haemostasis. The study included 40 patients with an indication for tooth extraction, divided into two groups: examination group (n = 30) and a control group (n = 10). The site of the extraction socket in the examination group was irradiated with LED (410 nm) until the bleeding stopped. The patients from the control group were treated by conventional gauze pressure to stop the bleeding (control group). The duration of irradiation and gauze pressure was measured and compared. The statistical analysis was performed with Student T-test. The examination group showed the shorter duration of bleeding compared to the control group for 13.67 seconds and 156 seconds, respectively. The most of the cases in the examination group were irradiated in 10 seconds (70%), followed by irradiation of 20 seconds (23.3%) and 30 seconds (6.6%). In the control group, the average time to stop the bleeding by the conventional method was 156 second. The blue-violet LED light shortens the bleeding time from the extraction socket after tooth extraction and may be a promising method for achieving haemostasis.

Laser Surgery of Soft Tissue in Orthodontics: Review of the Clinical Trials.

PubMed

Seifi, Massoud; Matini, Negin-Sadat

2017-01-01

Introduction: Recently, a wide variety of procedures have been done by laser application in orthodontics. Apart from the mentioned range of various treatments, laser has become a tool for many soft tissue surgeries as an alternative to conventional scalpel-based technique during orthodontic treatments in the management of soft tissue. Due to scarce information in the latter subject, this study was designed in order to include clinical trials that included soft tissue ablation by laser in orthodontics. Methods: Literature was searched based on PubMed and Google Scholar databases in 5 years (2010-2015) with English language restriction and clinical trial design. Studies that performed soft tissue application of laser during orthodontic treatment were extracted by the authors. Results: Only eight studies met the inclusion criteria. No significant difference was found between laser ablation and conventional scalpel technique in the matter of treatment outcome. However, few issues remained to clarify the differences in the mentioned procedures. Conclusion: Laser performance can be recommended in case of preceding less bleeding and discomfort during surgical procedure. There are still quandaries among clinical application of scalpel-based surgery in aesthetic region with bracket-bonded teeth. Precaution and knowledge regarding the characteristics of laser beam such as wavelength, frequency, power and timing is extremely needed.

Laser Surgery of Soft Tissue in Orthodontics: Review of the Clinical Trials

PubMed Central

Seifi, Massoud; Matini, Negin-Sadat

2017-01-01

Introduction: Recently, a wide variety of procedures have been done by laser application in orthodontics. Apart from the mentioned range of various treatments, laser has become a tool for many soft tissue surgeries as an alternative to conventional scalpel-based technique during orthodontic treatments in the management of soft tissue. Due to scarce information in the latter subject, this study was designed in order to include clinical trials that included soft tissue ablation by laser in orthodontics. Methods: Literature was searched based on PubMed and Google Scholar databases in 5 years (2010-2015) with English language restriction and clinical trial design. Studies that performed soft tissue application of laser during orthodontic treatment were extracted by the authors. Results: Only eight studies met the inclusion criteria. No significant difference was found between laser ablation and conventional scalpel technique in the matter of treatment outcome. However, few issues remained to clarify the differences in the mentioned procedures. Conclusion: Laser performance can be recommended in case of preceding less bleeding and discomfort during surgical procedure. There are still quandaries among clinical application of scalpel-based surgery in aesthetic region with bracket-bonded teeth. Precaution and knowledge regarding the characteristics of laser beam such as wavelength, frequency, power and timing is extremely needed. PMID:29263776

Refractive lenticule extraction small incision lenticule extraction: A new refractive surgery paradigm

PubMed Central

Ganesh, Sri; Brar, Sheetal; Arra, Raghavender Reddy

2018-01-01

Small incision lenticule extraction (SMILE), a variant of refractive lenticule extraction technology is becoming increasingly popular, as a flapless and minimally invasive form of laser vision correction (LVC) for the treatment of myopia and myopic astigmatism. This review aims at summarizing the principles, surgical technique, and clinical outcomes in terms of visual and refractive results, safety, efficacy, postoperative dry eye, aberrations, and biomechanics of SMILE and its comparison with other conventional techniques of LVC, such as laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK). Recent advancements in the laser frequency and energy delivery patterns, instrumentation, and surgical techniques have shown significant improvement in the visual recovery and outcomes after SMILE, compared to the initial results published by Sekundo and Shah et al. Most of the recently published literature on long-term outcomes of SMILE shows excellent stability of the procedure, especially for higher myopia. In terms of the postoperative dry eye, SMILE shows a clear advantage over LASIK as numerous studies have shown significant differences about the Schirmer's, Tear film break up time, corneal sensitivity, and corneal nerve regeneration to be better following SMILE compared to LASIK. There is some evidence that since the Bowman's membrane (BM) and the anterior lamellae remain intact after SMILE, this may be a potential advantage for corneal biomechanics over LASIK and PRK where the BM is either severed or ablated, respectively, however, the data on biomechanics are inconclusive at present. Overall, this procedure has proved to be promising, delivering equivalent, or better visual and refractive results to LASIK and providing clear advantage in terms of being a flapless, minimally invasive procedure with minimal pain and postoperative discomfort thus offering high patient satisfaction. PMID:29283117

Green ultrasound-assisted extraction of carotenoids based on the bio-refinery concept using sunflower oil as an alternative solvent.

PubMed

Li, Ying; Fabiano-Tixier, Anne Sylvie; Tomao, Valérie; Cravotto, Giancarlo; Chemat, Farid

2013-01-01

A green, inexpensive and easy-to-use method for carotenoids extraction from fresh carrots assisted by ultrasound was designed in this work. Sunflower oil was applied as a substitute to organic solvents in this green ultrasound-assisted extraction (UAE): a process which is in line with green extraction and bio-refinery concepts. The processing procedure of this original UAE was first compared with conventional solvent extraction (CSE) using hexane as solvent. Moreover, the UAE optimal conditions for the subsequent comparison were optimized using response surface methodology (RSM) and ultra performance liquid chromatography--diode array detector--mass spectroscopy (UPLC-DAD-MS). The results showed that the UAE using sunflower as solvent has obtained its highest β-carotene yield (334.75 mg/l) in 20 min only, while CSE using hexane as solvent obtained a similar yield (321.35 mg/l) in 60 min. The green UAE performed under optimal extraction conditions (carrot to oil ratio of 2:10, ultrasonic intensity of 22.5 W cm(-2), temperature of 40 °C and sonication time of 20 min) gave the best yield of β-carotene. Copyright © 2012 Elsevier B.V. All rights reserved.

Measurement of polychlorinated biphenyls in solid waste such as transformer insulation paper by supercritical fluid extraction and gas chromatography electron capture detection.

PubMed

Chikushi, Hiroaki; Fujii, Yuka; Toda, Kei

2012-09-21

In this work, a method for measuring polychlorinated biphenyls (PCBs) in contaminated solid waste was investigated. This waste includes paper that is used in electric transformers to insulate electric components. The PCBs in paper sample were extracted by supercritical fluid extraction and analyzed by gas chromatography-electron capture detection. The recoveries with this method (84-101%) were much higher than those with conventional water extraction (0.08-14%), and were comparable to those with conventional organic solvent extraction. Limit of detection was 0.0074 mg kg(-1) and measurable up to 2.5 mg kg(-1) for 0.5 g of paper sample. Data for real insulation paper by the proposed method agreed well with those by the conventional organic solvent extraction. Extraction from wood and concrete was also investigated and good performance was obtained as well as for paper samples. The supercritical fluid extraction is simpler, faster, and greener than conventional organic solvent extraction. Copyright © 2012 Elsevier B.V. All rights reserved.

Extraction of coffee silverskin to convert waste into a source of antioxidant

NASA Astrophysics Data System (ADS)

Tangguh, Patrick; Kusumocahyo, Samuel P.

2017-01-01

Coffee silverskin (CS) is a thin layer of coffee bean, and is regarded as a waste during coffee roasting process. In this work, coffee silverskin was extracted by three types of method: conventional extraction (CE) with agitation, conventional extraction (CE) without agitation and ultrasound-assisted extraction (UAE). The total phenolic content, the total flavonoid content and the antioxidant activity of the extract were analyzed. It was found that the type of extraction method, the extraction time and the extraction temperature strongly influenced the total phenolic content, the total flavonoid content and the antioxidant activity of the extract. Comparison between conventional extraction (CE) and ultrasound-assisted extraction (UAE) were statistically analyzed using 3-way ANOVA test. The optimum extraction time and temperature for each method were analyzed using 2-way ANOVA test. It was found that the optimum condition to obtain a high antioxidant activity of 68.9% was by using CE with agitation with the extraction time and temperature of 60 minutes and 60˚C, respectively.

Biliary sphincteroplasty facilitates retrieval of proximally migrated plastic biliary stent.

PubMed

Shah, Dharmesh K; Jain, Samit S; Somani, Piyush O; Rathi, Pravin M

2014-01-01

Proximal migration of biliary stents presents a technical challenge for the therapeutic endoscopist. It may require multiple, complicated corrective procedures resulting in significant morbidity to the patients. In this study we evaluated the utility of balloon biliary sphincteroplasty with CRE (Controlled Radial Expansion) Balloon Dilator on retrieval of proximally migrated biliary stents. We identified patients from our ERCP database who presented with proximal migration of biliary stent, between August 2011 and October 2013. Patients in whom the stent could not be retrieved with conventional methods, balloon sphincteroplasty was performed with a 12 mm CRETM Balloon Dilator (Boston Scientific). Stent removal was attempted with extraction balloon or basket thereafter. We identified 28 patients with proximal migration of biliary stents, placed for benign diseases of the common bile duct. Stent removal was successful in 18 patients (64.28%) with help of an extraction balloon or basket. Of the remaining 10 patients, balloon sphincteroplasty was successfully followed by stent removal in eight patients. Balloon biliary sphincteroplasty increases the success rate of retrieving proximally migrated biliary stents. The procedure is safe, technically easy and yields a good success rate in our experience.

Comparison of Enzymatic and Ultrasonic Extraction of Albumin from Defatted Pumpkin (Cucurbita pepo)
Seed Powder

PubMed Central

Tu, Gia Loi; Bui, Thi Hoang Nga; Tran, Thi Thu Tra; Ton, Nu Minh Nguyet

2015-01-01

Summary In this study, ultrasound- and enzyme-assisted extractions of albumin (water-soluble protein group) from defatted pumpkin (Cucurbita pepo) seed powder were compared. Both advanced extraction techniques strongly increased the albumin yield in comparison with conventional extraction. The extraction rate was two times faster in the ultrasonic extraction than in the enzymatic extraction. However, the maximum albumin yield was 16% higher when using enzymatic extraction. Functional properties of the pumpkin seed albumin concentrates obtained using the enzymatic, ultrasonic and conventional methods were then evaluated. Use of hydrolase for degradation of cell wall of the plant material did not change the functional properties of the albumin concentrate in comparison with the conventional extraction. The ultrasonic extraction enhanced water-holding, oil-holding and emulsifying capacities of the pumpkin seed albumin concentrate, but slightly reduced the foaming capacity, and emulsion and foam stability. PMID:27904383

Comparison of Enzymatic and Ultrasonic Extraction of Albumin from Defatted Pumpkin (Cucurbita pepo)
Seed Powder.

PubMed

Tu, Gia Loi; Bui, Thi Hoang Nga; Tran, Thi Thu Tra; Ton, Nu Minh Nguyet; Man Le, Van Viet

2015-12-01

In this study, ultrasound- and enzyme-assisted extractions of albumin (water-soluble protein group) from defatted pumpkin ( Cucurbita pepo ) seed powder were compared. Both advanced extraction techniques strongly increased the albumin yield in comparison with conventional extraction. The extraction rate was two times faster in the ultrasonic extraction than in the enzymatic extraction. However, the maximum albumin yield was 16% higher when using enzymatic extraction. Functional properties of the pumpkin seed albumin concentrates obtained using the enzymatic, ultrasonic and conventional methods were then evaluated. Use of hydrolase for degradation of cell wall of the plant material did not change the functional properties of the albumin concentrate in comparison with the conventional extraction. The ultrasonic extraction enhanced water-holding, oil-holding and emulsifying capacities of the pumpkin seed albumin concentrate, but slightly reduced the foaming capacity, and emulsion and foam stability.

A 5-year retrospective case series evaluating Brånemark Integration BioHelix (™) dental implants placed in a private practice by a specialist.

PubMed

Thomsson, Mats; Larsson Wexell, Cecilia

2013-09-01

To evaluate, in a case series, survival rate and complications of Brånemark Integration BioHelix(™) dental implants, placed according to conventional procedures in patients treated consecutively in a Swedish specialist private practice after 5 years. Eighty-three consecutively-treated patients received 89 final fixed prostheses supported by 310 implants placed according to 'conventional' procedure, i.e. no implants shorter than 10 mm, no immediate post-extraction implants and no bone-grafting procedures. In 70 patients, implants were left to heal submerged, whereas 13 patients were treated according to the one-stage protocol. All implants were incorporated in a prosthetic restoration. Probing was only performed when clinical signs of inflammation were present and this was then evaluated further with intra-oral radiographic examination. Outcome measures were implant survival and prosthetic complications. Five years after implant placement, two fixtures were removed because of loosening. One fixture was lost after 12 months in the lower jaw in one patient and one fixture was lost in the upper jaw in another patient after 3 years, both inserted using the two-stage technique. No other prosthetic complications occurred, giving a 99.3% cumulative survival rate. Brånemark Integration BioHelix(™) dental implants placed according to one- or two-stage procedures in patients in a private practice produced excellent 5-year results. Randomized clinical trials with suitable controls are suggested to confirm these results.

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.

Determination of polybrominated diphenyl ethers (PBDEs) in dust samples collected in air conditioning filters of different usage - method development.

PubMed

Śmiełowska, M; Zabiegała, B

2018-06-19

This study presents the results of studies aimed at the development of an analytical procedure for separation, identification, and determination of PBDEs compounds in dust samples collected from automotive cabin air filters and samples collected from filters installed as part of the air purification system in academic facilities. Ultrasound-assisted dispersive solid phase extraction (UA-dSPE) was found to perform better in terms of extract purification than the conventional SPE technique. GC-EIMS was used for final determination of analytes. The concentrations of PBDEs in car filters ranged from < LOD to 688 ng/g while from < LOD to 247 ng/g in dust from air conditioning filters. BDE-47 and BDE-100 were reported the dominating congeners. The estimated exposure to PBDEs via ingestion of dust from car filters varied from 0.00022 to 0.012 ng/day in toddlers and from 0.000036 to 0.0029 ng/day in adults; dust from air conditioning filters: from 0.017 to 0.25 ng/day in toddlers and from 0.0029 to 0.042 ng/day. In addition, an attempt was made at extracting PBDEs from a dust samples using the matrix solid-phase dispersion (MSPD) technique as a promising alternative to conventional SPE separations. Copyright © 2018 Elsevier B.V. All rights reserved.

Direct extraction of genomic DNA from maize with aqueous ionic liquid buffer systems for applications in genetically modified organisms analysis.

PubMed

Gonzalez García, Eric; Ressmann, Anna K; Gaertner, Peter; Zirbs, Ronald; Mach, Robert L; Krska, Rudolf; Bica, Katharina; Brunner, Kurt

2014-12-01

To date, the extraction of genomic DNA is considered a bottleneck in the process of genetically modified organisms (GMOs) detection. Conventional DNA isolation methods are associated with long extraction times and multiple pipetting and centrifugation steps, which makes the entire procedure not only tedious and complicated but also prone to sample cross-contamination. In recent times, ionic liquids have emerged as innovative solvents for biomass processing, due to their outstanding properties for dissolution of biomass and biopolymers. In this study, a novel, easily applicable, and time-efficient method for the direct extraction of genomic DNA from biomass based on aqueous-ionic liquid solutions was developed. The straightforward protocol relies on extraction of maize in a 10 % solution of ionic liquids in aqueous phosphate buffer for 5 min at room temperature, followed by a denaturation step at 95 °C for 10 min and a simple filtration to remove residual biopolymers. A set of 22 ionic liquids was tested in a buffer system and 1-ethyl-3-methylimidazolium dimethylphosphate, as well as the environmentally benign choline formate, were identified as ideal candidates. With this strategy, the quality of the genomic DNA extracted was significantly improved and the extraction protocol was notably simplified compared with a well-established method.

Supercritical CO2 assisted process for the production of high-purity and sterile nano-hydroxyapatite/chitosan hybrid scaffolds.

PubMed

Ruphuy, G; Souto-Lopes, M; Paiva, D; Costa, P; Rodrigues, A E; Monteiro, F J; Salgado, C L; Fernandes, M H; Lopes, J C; Dias, M M; Barreiro, M F

2018-04-01

Hybrid scaffolds composed of hydroxyapatite (HAp), in particular in its nanometric form (n-HAp), and chitosan (CS) are promising materials for non-load-bearing bone graft applications. The main constraints of their production concern the successful implementation of the final purification/neutralization and sterilization steps. Often, the used purification strategies can compromise scaffold structural features, and conventional sterilization techniques can result in material's thermal degradation and/or contamination with toxic residues. In this context, this work presents a process to produce n-HAp/CS scaffolds mimicking bone composition and structure, where an innovative single step based on supercritical CO 2 extraction was used for both purification and sterilization. A removal of 80% of the residual acetic acid was obtained (T = 75°C, p = 8.0 MPa, 2 extraction cycles of 2 h) giving rise to scaffolds exhibiting adequate interconnected porous structure, fast swelling and storage modulus compatible with non-load-bearing applications. Moreover, the obtained scaffolds showed cytocompatibility and osteoconductivity without further need of disinfection/sterilization procedures. Among the main advantages, the proposed process comprises only three steps (n-HAp/CS dispersion preparation; freeze-drying; and supercritical CO 2 extraction), and the supercritical CO 2 extraction show clear advantages over currently used procedures based on neutralization steps. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 965-975, 2018. © 2017 Wiley Periodicals, Inc.

Comparison of the atmospheric- and reduced-pressure HS-SPME strategies for analysis of residual solvents in commercial antibiotics using a steel fiber coated with a multiwalled carbon nanotube/polyaniline nanocomposite.

PubMed

Ghiasvand, Ali Reza; Nouriasl, Kolsoum; Yazdankhah, Fatemeh

2018-01-01

A low-cost, sensitive and reliable reduced-pressure headspace solid-phase microextraction (HS-SPME) setup was developed and evaluated for direct extraction of residual solvents in commercial antibiotics, followed by determination by gas chromatography with flame ionization detection (GC-FID). A stainless steel narrow wire was made porous and adhesive by platinization by a modified electrophoretic deposition method and coated with a polyaniline/multiwalled carbon nanotube nanocomposite. All experimental variables affecting the extraction efficiency were investigated for both atmospheric-pressure and reduced-pressure conditions. Comparison of the optimal experimental conditions and the results demonstrated that the reduced-pressure strategy leads to a remarkable increase in the extraction efficiency and reduction of the extraction time and temperature (10 min, 25 °Ϲ vs 20 min, 40 °Ϲ). Additionally, the reduced-pressure strategy showed better analytical performances compared with those obtained by the conventional HS-SPME-GC-FID method. Limit of detections, linear dynamic ranges, and relative standard deviations of the reduced-pressure HS-SPME procedure for benzene, toluene, ethylbenzene, and xylene (BTEX) in injectable solid drugs were obtained over the ranges of 20-100 pg g -1 , 0.02-40 μg g -1 , and 2.8-10.2%, respectively. The procedure developed was successful for the analysis of BTEX in commercial containers of penicillin, ampicillin, ceftriaxone, and cefazolin. Graphical abstract Schematic representation of the developed RP-HS-SPME setup.

Investigation into photostability of soybean oils by thermal lens spectroscopy

NASA Astrophysics Data System (ADS)

Savi, E. L.; Malacarne, L. C.; Baesso, M. L.; Pintro, P. T. M.; Croge, C.; Shen, J.; Astrath, N. G. C.

2015-06-01

Assessment of photochemical stability is essential for evaluating quality and the shelf life of vegetable oils, which are very important aspects of marketing and human health. Most of conventional methods used to investigate oxidative stability requires long time experimental procedures with high consumption of chemical inputs for the preparation or extraction of sample compounds. In this work we propose a time-resolved thermal lens method to analyze photostability of edible oils by quantitative measurement of photoreaction cross-section. An all-numerical routine is employed to solve a complex theoretical problem involving photochemical reaction, thermal lens effect, and mass diffusion during local laser excitation. The photostability of pure oil and oils with natural and synthetic antioxidants is investigated. The thermal lens results are compared with those obtained by conventional methods, and a complete set of physical properties of the samples is presented.

Natural colorants: Pigment stability and extraction yield enhancement via utilization of appropriate pretreatment and extraction methods.

PubMed

Ngamwonglumlert, Luxsika; Devahastin, Sakamon; Chiewchan, Naphaporn

2017-10-13

Natural colorants from plant-based materials have gained increasing popularity due to health consciousness of consumers. Among the many steps involved in the production of natural colorants, pigment extraction is one of the most important. Soxhlet extraction, maceration, and hydrodistillation are conventional methods that have been widely used in industry and laboratory for such a purpose. Recently, various non-conventional methods, such as supercritical fluid extraction, pressurized liquid extraction, microwave-assisted extraction, ultrasound-assisted extraction, pulsed-electric field extraction, and enzyme-assisted extraction have emerged as alternatives to conventional methods due to the advantages of the former in terms of smaller solvent consumption, shorter extraction time, and more environment-friendliness. Prior to the extraction step, pretreatment of plant materials to enhance the stability of natural pigments is another important step that must be carefully taken care of. In this paper, a comprehensive review of appropriate pretreatment and extraction methods for chlorophylls, carotenoids, betalains, and anthocyanins, which are major classes of plant pigments, is provided by using pigment stability and extraction yield as assessment criteria.

Are minimally invasive procedures harder to acquire than conventional surgical procedures?

PubMed

Hiemstra, Ellen; Kolkman, Wendela; le Cessie, Saskia; Jansen, Frank Willem

2011-01-01

It is frequently suggested that minimally invasive surgery (MIS) is harder to acquire than conventional surgery. To test this hypothesis, residents' learning curves of both surgical skills are compared. Residents had to be assessed using a general global rating scale of the OSATS (Objective Structured Assessment of Technical Skills) for every procedure they performed as primary surgeon during a 3-month clinical rotation in gynecological surgery. Nine postgraduate-year-4 residents collected a total of 319 OSATS during the 2 years and 3 months investigation period. These assessments concerned 129 MIS (laparoscopic and hysteroscopic) and 190 conventional (open abdominal and vaginal) procedures. Learning curves (in this study defined as OSATS score plotted against procedure-specific caseload) for MIS and conventional surgery were compared using a linear mixed model. The MIS curve revealed to be steeper than the conventional curve (1.77 vs. 0.75 OSATS points per assessed procedure; 95% CI 1.19-2.35 vs. 0.15-1.35, p < 0.01). Basic MIS procedures do not seem harder to acquire during residency than conventional surgical procedures. This may have resulted from the incorporation of structured MIS training programs in residency. Hopefully, this will lead to a more successful implementation of the advanced MIS procedures. Copyright © 2010 S. Karger AG, Basel.

Evaluation of photodynamic therapy using a light-emitting diode lamp against Enterococcus faecalis in extracted human teeth.

PubMed

Rios, Alejandro; He, Jianing; Glickman, Gerald N; Spears, Robert; Schneiderman, Emet D; Honeyman, Allen L

2011-06-01

Photodynamic therapy (PDT) with high-power lasers as the light source has been proven to be effective in disinfecting root canals. The aim of this study was to evaluate the antimicrobial effect of PDT using toluidine blue O (TBO) and a low-energy light-emitting diode (LED) lamp after the conventional disinfection protocol of 6% NaOCl. Single-rooted extracted teeth were cleaned, shaped, and sealed at the apex before incubation with Enterococcus faecalis for 2 weeks. Roots were randomly assigned to five experimental groups and three control groups. Dentin shavings were collected from the root canals of all groups with a #50/.06 rotary file, colony-forming units were determined, and the bacterial survival rate was calculated for each treatment. The bacterial survival rate of the NaOCl/TBO/light group (0.1%) was significantly lower (P < .005) than the NaOCl (0.66%) and TBO/light groups (2.9%). PDT using TBO and a LED lamp has the potential to be used as an adjunctive antimicrobial procedure in conventional endodontic therapy. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Antimutagenic and antioxidant properties of the aqueous extracts of organic and conventional grapevine Vitis labrusca cv. Isabella leaves in V79 cells.

PubMed

Trindade, Cristiano; Bortolini, Giovana Vera; Costa, Bárbara Segalotto; Anghinoni, Joanna Carra; Guecheva, Temenouga Nikolova; Arias, Ximena; Césio, Maria Verónica; Heinzen, Horácio; Moura, Dinara Jaqueline; Saffi, Jenifer; Salvador, Mirian; Henriques, João Antonio Pêgas

2016-01-01

Grapes are one of the most commonly consumed fruit, in both fresh and processed forms; however, a significant amount is disposed of in the environment. Searching for a use of this waste, the antigenotoxic, antimutagenic, and antioxidant activities of aqueous extracts from organic and conventional Vitis labrusca leaves were determined using V79 cells as model. The antigenotoxic activity was analyzed by the alkaline comet assay using endonuclease III and formamidopyrimidine DNA glycosylase enzymes. The antimutagenic property was assessed through the micronucleus (MN) formation, and antioxidant activities were assessed using 2',7'-dichlorodihydrofluorescin diacetate (DCFH-DA) assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH(●)) radical scavenging, as well as with superoxide dismutase (SOD) and catalase (CAT) activity assays. In addition, phenolic content and ascorbic acid levels of both extracts were determined. Data showed that both organic and conventional grapevine leaves extracts possessed antigenotoxic and antimutagenic properties. The extract of organic leaves significantly reduced intracellular reactive oxygen species (ROS) levels in V79 cells, and displayed greater ability for DPPH(●) scavenging and higher SOD and CAT activities than extract from conventional leaves. Further, the extract from organic leaves contained higher phenolic and ascorbic acid concentrations. In summary, extracts from organic and conventional grape leaves induced important in vitro biological effects.

Application of fermentation for isoflavone extraction from soy molasses

NASA Astrophysics Data System (ADS)

Duru, K. C.; Kovaleva, E. G.; Glukhareva, T. V.

2017-09-01

Extraction of isoflavones from soy products remains a major challenge for researchers. Different extraction techniques have been employed but the need to use a cheap green extraction technique remains the main focus. This study applied fermentation of soy molasses using Saccharomyces cerevisiae for extraction of isoflavones and compared this technique to the conventional extraction method. The aluminum chloride colorimetric method was used for the determination of total flavonoid content of extracts. The highest yield was observed from extraction using ethyl acetate after fermentation of soy molasses and the lowest one was given by the extract from conventional extraction method. The DPPH radical scavenging activities of the extracts were also compared. The extract obtained using ethyl acetate after fermentation showed the highest antioxidant activity (0.0269 meq), while extract from conventional extraction had the lowest antioxidant activity (0.0055 meq). The effect of time on daidzein yield was studied using HPLC standard addition method. Daidzein concentration was higher in extract obtained at t = 80 min (3.82 ± 0.11 mg of daidzein /g of extract) as compared to that obtained at t = 60 min (2.89 ± 0.10 mg of daidzein /g of extract).

Optimization of the microwave-assisted extraction of phlorotannins from Saccharina japonica Aresch and evaluation of the inhibitory effects of phlorotannin-containing extracts on HepG2 cancer cells

NASA Astrophysics Data System (ADS)

He, Zhizhou; Chen, Yongshun; Chen, Yongheng; Liu, Haohuai; Yuan, Guanfu; Fan, Yaming; Chen, Kun

2013-09-01

The use of a microwave-assisted extraction (MAE) method for the extraction of phlorotannins from Saccharina japonica Aresch ( S. japonica) has been evaluated with particular emphasis on the influential parameters, including the ethanol concentration, solid/liquid ratio, extraction time, extraction temperature, and microwave power. The MAE procedure was optimized using single-factor design and orthogonal array design (OAD). The content of total phlorotannins in S. japonica was determined using a Folin-Ciocalteu (FC) assay. A maximum total phlorotannin content of 0.644 mg of phloroglucinol equivalent per gram of dry weight plant (mg PGE/g DW) was obtained using the optimized model, which included an ethanol concentration of 55%, solid/liquid ratio of 1:8, extraction time of 25 min, irradiation power of 400 W, and temperature of 60°C. Under similar conditions, the application of a conventional extraction method led to a lower phlorotannin yield of 0.585 mg PGE/g WD. These results demonstrated that the MAE approach provided better results for the extraction of phlorotannins from S. japonica and was a promising technique for the extraction of phenolic compounds from S. japonica and other materials. In addition, screening tests for the inhibitory activity showed that the phlorotannin-containing extracts significantly inhibited the growth of human hepatocellular carcinoma cells (HepG2) by inducing their apoptosis. The morphological changes that occurred during cell apoptosis were characterized using Hoechst33258 staining.

40 CFR 80.131 - Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously...

Code of Federal Regulations, 2010 CFR

2010-07-01

..., certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline... Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline, and butane blenders. (a) Attest procedures for GTAB. The following are...

40 CFR 80.131 - Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously...

Code of Federal Regulations, 2011 CFR

2011-07-01

..., certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline... Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline, and butane blenders. (a) Attest procedures for GTAB. The following are...

40 CFR 80.131 - Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously...

Code of Federal Regulations, 2013 CFR

2013-07-01

..., certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline... Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline, and butane blenders. (a) Attest procedures for GTAB. The following are...

40 CFR 80.131 - Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously...

Code of Federal Regulations, 2012 CFR

2012-07-01

..., certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline... Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline, and butane blenders. (a) Attest procedures for GTAB. The following are...

40 CFR 80.131 - Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously...

Code of Federal Regulations, 2014 CFR

2014-07-01

..., certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline... Agreed upon procedures for GTAB, certain conventional gasoline imported by truck, previously certified gasoline used to produce gasoline, and butane blenders. (a) Attest procedures for GTAB. The following are...

Power of Orbitrap-based LC-high resolution-MS/MS for comprehensive drug testing in urine with or without conjugate cleavage or using dried urine spots after on-spot cleavage in comparison to established LC-MSn or GC-MS procedures.

PubMed

Michely, Julian A; Meyer, Markus R; Maurer, Hans H

2018-01-01

Reliable, sensitive, and comprehensive urine screening procedures by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS) with low or high resolution (HR) are of high importance for drug testing, adherence monitoring, or detection of toxic compounds. Besides conventional urine sampling, dried urine spots are of increasing interest. In the present study, the power of LC-HR-MS/MS was investigated for comprehensive drug testing in urine with or without conjugate cleavage or using dried urine spots after on-spot cleavage in comparison to established LC-MS n or GC-MS procedures. Authentic human urine samples (n = 103) were split in 4 parts. One aliquot was prepared by precipitation (UP), one by UP with conjugate cleavage (UglucP), one spot on filter paper cards and prepared by on-spot cleavage followed by liquid extraction (DUSglucE), and one worked-up by acid hydrolysis, liquid-liquid extraction, and acetylation for GC-MS analysis. The 3 series of LC-HR-MS/MS results were compared among themselves, to corresponding published LC-MS n data, and to screening results obtained by conventional GC-MS. The reference libraries used for the 3 techniques contained over 4500 spectra of parent compounds and their metabolites. The number of all detected hits (770 drug intakes) was set to 100%. The LC-HR-MS/MS approach detected 80% of the hits after UP, 89% after UglucP, and 77% after DUSglucE, which meant over one-third more hits in comparison to the corresponding published LC-MS n results with ≤49% detected hits. The GC-MS approach identified 56% of all detected hits. In conclusion, LC-HR-MS/MS provided the best screening results after conjugate cleavage and precipitation. Copyright © 2017 John Wiley & Sons, Ltd.

Application of ionic liquids based microwave-assisted simultaneous extraction of carnosic acid, rosmarinic acid and essential oil from Rosmarinus officinalis.

PubMed

Liu, Tingting; Sui, Xiaoyu; Zhang, Rongrui; Yang, Lei; Zu, Yuangang; Zhang, Lin; Zhang, Ying; Zhang, Zhonghua

2011-11-25

An ionic liquid based microwave-assisted simultaneous extraction and distillation (ILMSED) method has been developed for the effective extraction of carnosic acid (CA), rosmarinic acid (RA) and essential oil (EO) from Rosmarinus officinalis. A series of 1-alkyl-3-methylimidazolium ionic liquids differing in composition of anion and cation were evaluated for extraction yield in this work. The results obtained indicated that the anions and cations of ionic liquids had influences on the extraction of CA and RA, 1.0M 1-octyl-3-methylimidazolium bromide ([C8mim]Br) solution was selected as solvent. In addition, the ILMSED procedures for the three target ingredients were optimized and compared with other conventional extraction techniques. ILMSED gave the best result due to the highest extraction yield within the shortest extraction time for CA and RA. The novel process developed offered advantages in term of yield and selectivity of EO and shorter isolation time (20 min in comparison of 4h of hydrodistillation), and provides a more valuable EO (with high amount of oxygenated compounds). The microstructures and chemical structures of rosemary samples before and after extraction were also investigated. Moreover, the proposed method was validated by the stability, repeatability and recovery experiments. The results indicated that the developed ILMSED method provided a good alternative for the both extraction of non-volatile compounds (CA and RA) and EO from rosemary as well as other herbs. Copyright © 2011 Elsevier B.V. All rights reserved.

Rapid detection of Ganoderma-infected oil palms by microwave ergosterol extraction with HPLC and TLC.

PubMed

Muniroh, M S; Sariah, M; Zainal Abidin, M A; Lima, N; Paterson, R R M

2014-05-01

Detection of basal stem rot (BSR) by Ganoderma of oil palms was based on foliar symptoms and production of basidiomata. Enzyme-Linked Immunosorbent Assays-Polyclonal Antibody (ELISA-PAB) and PCR have been proposed as early detection methods for the disease. These techniques are complex, time consuming and have accuracy limitations. An ergosterol method was developed which correlated well with the degree of infection in oil palms, including samples growing in plantations. However, the method was capable of being optimised. This current study was designed to develop a simpler, more rapid and efficient ergosterol method with utility in the field that involved the use of microwave extraction. The optimised procedure involved extracting a small amount of Ganoderma, or Ganoderma-infected oil palm suspended in low volumes of solvent followed by irradiation in a conventional microwave oven at 70°C and medium high power for 30s, resulting in simultaneous extraction and saponification. Ergosterol was detected by thin layer chromatography (TLC) and quantified using high performance liquid chromatography with diode array detection. The TLC method was novel and provided a simple, inexpensive method with utility in the field. The new method was particularly effective at extracting high yields of ergosterol from infected oil palm and enables rapid analysis of field samples on site, allowing infected oil palms to be treated or culled very rapidly. Some limitations of the method are discussed herein. The procedures lend themselves to controlling the disease more effectively and allowing more effective use of land currently employed to grow oil palms, thereby reducing pressure to develop new plantations. Copyright © 2014 Elsevier B.V. All rights reserved.

Preparative isolation, fast centrifugal partition chromatography purification and biological activity of cajaflavanone from Derris ferruginea stems.

PubMed

Morel, Sylvie; Landreau, Anne; Nguyen, Van Hung; Derbré, Séverine; Grellier, Philippe; Pape, Patrice Le; Pagniez, Fabrice; Litaudon, Marc; Richomme, Pascal

2012-01-01

The Derris genus is known to contain flavonoid derivatives, including prenylated flavanones and isoflavonoids such as rotenoids, which are generally associated with significant biological activity. To develop an efficient preparative isolation procedure for bioactive cajaflavanone. Fast centrifugal partition chromatography (FCPC) was optimised to purify cajaflavanone from Derris ferruginea stems in a single step as compared to fractionation from the cyclohexane extract by successive conventional solid-liquid chromatography procedures. The purification yield, purity, time and solvent consumption per procedure are described. The anti-fungal, anti-bacterial, anti-leishmanial, anti-plasmodial, anti-oxidant activities and the inhibition of advanced glycation end-products (AGEs) by cajaflavanone accumulation are described. FCPC enabled cajaflavanone purification in a single separation step, yielding sufficient quantities to perform in vitro biological screening. Interestingly, cajaflavanone had an inhibitory effect on the formation of AGEs, without displaying any in vitro anti-oxidant activity. A simple and efficient procedure, in comparison with other preparative methods, for bioactive cajaflavone purification has been developed using FCPC. Copyright © 2011 John Wiley & Sons, Ltd.

Microwave- and ultrasound-assisted extraction of vanillin and its quantification by high-performance liquid chromatography in Vanilla planifolia.

PubMed

Sharma, Anuj; Verma, Subash Chandra; Saxena, Nisha; Chadda, Neetu; Singh, Narendra Pratap; Sinha, Arun Kumar

2006-03-01

Microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and conventional extraction of vanillin and its quantification by HPLC in pods of Vanilla planifolia is described. A range of nonpolar to polar solvents were used for the extraction of vanillin employing MAE, UAE and conventional methods. Various extraction parameters such as nature of the solvent, solvent volume, time of irradiation, microwave and ultrasound energy inputs were optimized. HPLC was performed on RP ODS column (4.6 mm ID x 250 mm, 5 microm, Waters), a photodiode array detector (Waters 2996) using gradient solvent system of ACN and ortho-phosphoric acid in water (0.001:99.999 v/v) at 25 degrees C. Regression equation revealed a linear relationship (r2 > 0.9998) between the mass of vanillin injected and the peak areas. The detection limit (S/N = 3) and limit of quantification (S/N = 10) were 0.65 and 1.2 microg/g, respectively. Recovery was achieved in the range 98.5-99.6% for vanillin. Maximum yield of vanilla extract (29.81, 29.068 and 14.31% by conventional extraction, MAE and UAE, respectively) was found in a mixture of ethanol/water (40:60 v/v). Dehydrated ethanolic extract showed the highest amount of vanillin (1.8, 1.25 and 0.99% by MAE, conventional extraction and UAE, respectively).

Environmental and toxicological planning in polymer production and disposal.

PubMed Central

Levinskas, G J

1975-01-01

There is neither a prescribed format nor a rigid sequence of testing to follow for the assessment of health and environmental effects of chemicals. Conventional animal toxicity tests plus medical surveillance and monitoring of exposed human populations will provide knowledge of the biological effects of chemicals and assurance that they can be handled safely. Useful information also can be derived from other test procedures. These include extraction studies to measure the amounts of additives which can leach from polymers, toxicity tests using aquatic organisms and birds, and determination of the biodegradability of materials and their potential for accumulation and magnification in biological systems. Current concern over pyrolysis products of polymers points up the need for defining the variables involved and development of test procedures by which meaningful evaluations of potential health hazards can be made. PMID:1175554

Efficacy of bone substitute material in preserving volume when placing a maxillary immediate complete denture: study protocol for the PANORAMIX randomized controlled trial.

PubMed

Rignon-Bret, Christophe; Hadida, Alain; Aidan, Alexis; Nguyen, Thien-Huong; Pasquet, Gerard; Fron-Chabouis, Helene; Wulfman, Claudine

2016-05-20

Bone preservation is an essential issue in the context of last teeth extraction and complete edentulism. The intended treatment, whether a complete denture or an implant placement, is facilitated with a voluminous residual ridge. Bone resorption after multiple extractions has not been as well studied as the bone resorption that occurs after the extraction of a single tooth. Recent advances in bone substitute materials have revived this issue. The purpose of this study is to evaluate the interest in using bone substitute material to fill the socket after last teeth extraction in a maxillary immediate complete denture procedure compared with the conventional protocol without socket filling. A randomized, controlled, clinical trial was designed. The 34 participants eligible for maxillary immediate complete denture were divided into two groups. Complete dentures were prepared despite persistence of the last anterior teeth. The control group received a conventional treatment including denture placement immediately after extractions. In the experimental group, in addition to the immediate denture placement, a xenograft bone-substitute material (Bio-Oss Collagen®) was placed in the fresh sockets. The primary outcome of the study is to compare mean bone ridge height loss 1 year after maxillary immediate complete denture placement, with or without bone-substitute material, in incisor and canine sockets. The secondary outcomes are to compare the average bone ridge height and width loss for each extraction site. An original quantitative evaluation method using cone beam computed tomography was designed for reproducible measurements, with a radio-opaque denture duplicate. Two independent operators perform the radiologic measurements. The immediate complete denture technique limits bone resorption in multiple extraction situations and thus allows better denture retention and better options for implant placement. To compare the benefit of using any bone socket-filling material, we proposed a quantitative evaluation protocol of resorption in the specific case of the last anterior maxillary teeth extraction with immediate denture placement. ClinicalTrials.gov, NCT02120053 . Registered on 18 April 2014.

Seismic instantaneous frequency extraction based on the SST-MAW

NASA Astrophysics Data System (ADS)

Liu, Naihao; Gao, Jinghuai; Jiang, Xiudi; Zhang, Zhuosheng; Wang, Ping

2018-06-01

The instantaneous frequency (IF) extraction of seismic data has been widely applied to seismic exploration for decades, such as detecting seismic absorption and characterizing depositional thicknesses. Based on the complex-trace analysis, the Hilbert transform (HT) can extract the IF directly, which is a traditional method and susceptible to noise. In this paper, a robust approach based on the synchrosqueezing transform (SST) is proposed to extract the IF from seismic data. In this process, a novel analytical wavelet is developed and chosen as the basic wavelet, which is called the modified analytical wavelet (MAW) and comes from the three parameter wavelet. After transforming the seismic signal into a sparse time-frequency domain via the SST taking the MAW (SST-MAW), an adaptive threshold is introduced to improve the noise immunity and accuracy of the IF extraction in a noisy environment. Note that the SST-MAW reconstructs a complex trace to extract seismic IF. To demonstrate the effectiveness of the proposed method, we apply the SST-MAW to synthetic data and field seismic data. Numerical experiments suggest that the proposed procedure yields the higher resolution and the better anti-noise performance compared to the conventional IF extraction methods based on the HT method and continuous wavelet transform. Moreover, geological features (such as the channels) are well characterized, which is insightful for further oil/gas reservoir identification.

Genotoxicity of mercury used in chromosome aberration tests.

PubMed

Akiyama, M; Oshima, H; Nakamura, M

2001-01-01

The purpose of this study was to investigate the genotoxic effects of Hg released from dental amalgams. The chromosome aberration test was conducted using original extracts and their diluted solutions of conventional type amalgam and high copper amalgam. The concentrations of Hg, Cu and Ag in the original extract of high copper amalgam were 17.64, 7.97 and 43.90 microM, respectively. Those in the original extract of conventional type amalgam were 20.63, 7.87 and 14.79 microM, respectively. 10 and 30 microM Hg(2+) were also used for comparison. The frequency of chromosome aberrations was below 5% with 0 microM Hg(2+) and with a triple dilution of high copper amalgam extract, containing 5.88 microM Hg, 14.63 microM Cu and 2.65 microM Ag. However, 9.5% of the cells showed chromosome aberrations with a quadruple dilution of conventional type amalgam, containing 5.15 microM Hg, 3.69 microM Cu and 1.96 microM Ag. The amount of Hg in the quadruple dilution of conventional type amalgam was less than that in the triple dilution of high copper amalgam extract and 10 microM Hg(2+). A concentration of 30 microM Hg(2+) caused 34.5% of the cells to show chromosome aberrations while with a two-thirds dilution of high copper amalgam extract, containing 11.76 microM Hg, 29.26 microM Cu and 5.31 microM Ag, 58.5% of the cells showed chromosome aberrations. A two-thirds dilution of high copper amalgam extract induced more chromosome aberrations than 30 microM Hg(2+), although the amount of Hg was less than 30 microM Hg(2+). A triple dilution of conventional type amalgam extract, original extracts of conventional type amalgam and high copper amalgam and 100 microM Hg(2+) were induced few metaphases. It was revealed that the conventional type amalgam induced chromosome aberrations with quadruple dilution where cell viability was about 80% and that the high copper amalgam induced a high level of chromosome aberrations with the two-thirds dilution. The effects of low level Hg on humans are not clear.

Matrix solid phase dispersion-assisted BCR sequential extraction method for metal partitioning in surface estuarine sediments.

PubMed

Martínez-Fernández, Marta; Barciela-Alonso, María Carmen; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar

2011-01-15

The BCR (the Community Bureau of Reference) of the European Union sequential extraction scheme for metal partitioning in estuarine sediments has been accelerated by using a matrix solid phase dispersion (MSPD) approach. The MSPD assisted BCR procedure consists of passing the extractants proposed by conventional BCR protocol (0.11 M acetic acid, 0.1M hydroxylammonium chloride and 8.8M hydrogen peroxide plus 1M ammonium acetate) through the dispersed sample packaged inside a disposable syringe. Different silica-, magnesium- and aluminium-based materials were tested as dispersing agents and sea sand was found to offer the best performances. Variables for assisting the three stages of the BCR protocol were optimized, and accurate results were obtained when assisting the first and the third stages (exchangeable and oxidizable fractions, respectively). However, lack of accuracy was observed when assisting the second step (reducible fraction) and this result agrees with most of the assisted BCR procedures for which extracting the reducible fraction is the most troublesome stage. The organic matter oxidation (third stage) was successfully assisted by passing hydrogen peroxide at 50°C through the dispersed sample inside de syringe just before passing ammonium acetate. Therefore, the time-consuming and unsafe conventional organic matter oxidation processes, commonly performed even for microwave/ultrasounds assisted BCR procedures, are totally avoided. Inductively coupled plasma-mass spectrometry (ICP-MS) was used as a selective detector. The target elements were Cd, Co, Cr, Mn, Ni, Sr and Zn (first stage), Cd, Co and Ni (second stage), and Co, Cr, Mn, Ni, Sr and Zn (third stage). Repeatability of the method (n=7) was good, and RSDs values of 9, 10, 10, 8, 8, 3 and 8% was obtained for Cd, Co, Cr, Mn, Ni, Sr and Zn, respectively (first stage); 10, 9 and 9% for Cd, Co and Ni, respectively (second stage); and 6, 2, 3, 4, 7 and 9% Co, Cr, Mn, Ni, Sr and Zn, respectively (third stage). The procedure was also validated by analysing two certified reference materials (CRM 601 and CRM 701). Good accuracy was obtained for the target elements extracted at the first stage: Cd (4.0 ± 0.1 and 7.3 ± 0.09 μg g(-1) in CRM 601 and CRM 701, respectively), Cr (0.36 ± 0.008 and 2.21 ± 0.08 μg g(-1) in CRM 601 and CRM 701, respectively), Ni (8.0 ± 0.3 and 15.4 ± 0.3 μg g(-1) in CRM 601 and CRM 701, respectively) and Zn (262 ± 3 and 203 ± 3 μg g(-1) in CRM 601 and CRM 701, respectively). Also, good accuracy was observed for elements extracted at the third step: Cd (1.8 ± 0.09 and 0.29 ± 0.03 μg g(-1) in CRM 601 and CRM 701, respectively), Cr (145 ± 4 μg g(-1) in CRM 701), Ni (8.2 ± 0.7 and 15.1 ± 0.5 μg g(-1) in CRM 601 and CRM 701, respectively) and Zn (45 ± 0.7 μg g(-1) in CRM 701). Copyright © 2010 Elsevier B.V. All rights reserved.

Sediment Sampling in Estuarine Mudflats with an Aerial-Ground Robotic Team

PubMed Central

Deusdado, Pedro; Guedes, Magno; Silva, André; Marques, Francisco; Pinto, Eduardo; Rodrigues, Paulo; Lourenço, André; Mendonça, Ricardo; Santana, Pedro; Corisco, José; Almeida, Susana Marta; Portugal, Luís; Caldeira, Raquel; Barata, José; Flores, Luis

2016-01-01

This paper presents a robotic team suited for bottom sediment sampling and retrieval in mudflats, targeting environmental monitoring tasks. The robotic team encompasses a four-wheel-steering ground vehicle, equipped with a drilling tool designed to be able to retain wet soil, and a multi-rotor aerial vehicle for dynamic aerial imagery acquisition. On-demand aerial imagery, properly fused on an aerial mosaic, is used by remote human operators for specifying the robotic mission and supervising its execution. This is crucial for the success of an environmental monitoring study, as often it depends on human expertise to ensure the statistical significance and accuracy of the sampling procedures. Although the literature is rich on environmental monitoring sampling procedures, in mudflats, there is a gap as regards including robotic elements. This paper closes this gap by also proposing a preliminary experimental protocol tailored to exploit the capabilities offered by the robotic system. Field trials in the south bank of the river Tagus’ estuary show the ability of the robotic system to successfully extract and transport bottom sediment samples for offline analysis. The results also show the efficiency of the extraction and the benefits when compared to (conventional) human-based sampling. PMID:27618060

Simultaneous determination of quinolones in fish by liquid chromatography coupled with fluorescence detection: comparison of sub-2 microm particles and conventional C18 columns.

PubMed

Zhang, Hong; Chen, Si; Lu, Yanbin; Dai, Zhiyuan

2010-07-01

A simple and effective multi-residue analysis method is presented for the extraction and determination of eleven quinolones (pipemidic acid, enoxacin, norfloxacin, ciprofloxacin, lomefloxacin, enrofloxacin, gatifloxacin, difloxacin, oxolinic acid, nalidixic acid and flumequine) in fish tissues. In this study, multi-residue separations on four columns packed with 5 microm or sub-2 microm particles were simultaneously developed for the purpose of comparison. Various gradients were optimized and best resolutions were achieved on each column. A short and sub-2 microm particle-sized HPLC column was chosen for its advantages in analysis time and column performance. Additionally, considering the matrix effect of the complex crude fish tissue, an effective extraction protocol was also established for sample pre-treatment procedure. Good recoveries (71-98%) were obtained from samples fortified with a mix of eleven quinolones at three levels, with satisfactory relative standard deviations and limits of detection. As a result, the sub-2 microm HPLC column and proposed analytical procedures have been evaluated and applied to the analysis of different fish tissues. Detectable residues were observed in 8 of 30 samples, at concentrations ranging from 4.74 to 23.27 microg/kg.

Comparative study on conventional, ultrasonication and microwave assisted extraction of γ-oryzanol from rice bran.

PubMed

Kumar, Pramod; Yadav, Devbrat; Kumar, Pradyuman; Panesar, Paramjeet Singh; Bunkar, Durga Shankar; Mishra, Diwaker; Chopra, H K

2016-04-01

In present study, conventional, ultrasonic and microwave assisted extraction methods were compared with the aim of optimizing best fitting solvent and method, solvent concentration and digestion time for high yield of γ-oryzanol from rice bran. Petroleum ether, hexane and methanol were used to prepare extracts. Extraction yield were evaluated for giving high crude oil yield, total phenolic content (TPC) and γ-oryzanol content. Gas chromatography-mass spectrophotometry was used for the determination of γ-oryzanol concentration. The highest concentration of γ-oryzanol was detected in methanolic extracts of microwave treatment (85.0 ppm) followed by ultrasonication (82.0 ppm) and conventional extraction method (73.5 ppm). Concentration of γ-oryzanol present in the extracts was found to be directly proportional to the total phenolic content. A combination of 80 % methanolic concentration and 55 minutes digestion time of microwave treatment yielded the best extraction method for TPC and thus γ-oryzanol (105 ppm).

Conventional and Accelerated-Solvent Extractions of Green Tea (Camellia sinensis) for Metabolomics-based Chemometrics

PubMed Central

Kellogg, Joshua J.; Wallace, Emily D.; Graf, Tyler N.; Oberlies, Nicholas H.; Cech, Nadja B.

2018-01-01

Metabolomics has emerged as an important analytical technique for multiple applications. The value of information obtained from metabolomics analysis depends on the degree to which the entire metabolome is present and the reliability of sample treatment to ensure reproducibility across the study. The purpose of this study was to compare methods of preparing complex botanical extract samples prior to metabolomics profiling. Two extraction methodologies, accelerated solvent extraction and a conventional solvent maceration, were compared using commercial green tea [Camellia sinensis (L.) Kuntze (Theaceae)] products as a test case. The accelerated solvent protocol was first evaluated to ascertain critical factors influencing extraction using a D-optimal experimental design study. The accelerated solvent and conventional extraction methods yielded similar metabolite profiles for the green tea samples studied. The accelerated solvent extraction yielded higher total amounts of extracted catechins, was more reproducible, and required less active bench time to prepare the samples. This study demonstrates the effectiveness of accelerated solvent as an efficient methodology for metabolomics studies. PMID:28787673

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

PubMed

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

2007-05-01

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

Ultrasound-assisted extraction of rare-earth elements from carbonatite rocks.

PubMed

Diehl, Lisarb O; Gatiboni, Thais L; Mello, Paola A; Muller, Edson I; Duarte, Fabio A; Flores, Erico M M

2018-01-01

In view of the increasing demand for rare-earth elements (REE) in many areas of high technology, alternative methods for the extraction of these elements have been developed. In this work, a process based on the use of ultrasound for the extraction of REE from carbonatite (an igneous rock) is proposed to avoid the use of concentrated reagents, high temperature and excessive extraction time. In this pioneer work for REE extraction from carbonatite rocks in a preliminary investigation, ultrasonic baths, cup horn systems or ultrasound probes operating at different frequencies and power were evaluated. In addition, the power released to the extraction medium and the ultrasound amplitude were also investigated and the temperature and carbonatite mass/volume of extraction solution ratio were optimized to 70°C and 20mg/mL, respectively. Better extraction efficiencies (82%) were obtained employing an ultrasound probe operating at 20kHz for 15min, ultrasound amplitude of 40% (692Wdm -3 ) and using a diluted extraction solution (3% v/v HNO 3 +2% v/v HCl). It is important to mention that high extraction efficiency was obtained even using a diluted acid mixture and relatively low temperature in comparison to conventional extraction methods for REE. A comparison of results with those obtained by mechanical stirring (500rpm) using the same conditions (time, temperature and extraction solution) was carried out, showing that the use of ultrasound increased the extraction efficiency up to 35%. Therefore, the proposed ultrasound-assisted procedure can be considered as a suitable alternative for high efficiency extraction of REE from carbonatite rocks. Copyright © 2017 Elsevier B.V. All rights reserved.

An inorganic boronate affinity in-needle monolithic device for specific capture of cis-diol containing compounds.

PubMed

Jin, Shanxia; Zhang, Wei; Yang, Qin; Dai, Lili; Zhou, Ping

2018-02-01

In this work, inorganic boronate affinity monolith was prepared by in situ synthesis in 0.33mm i.d. stainless steel needle through sol-gel process using tetraethoxysilane and tetrabutyl orthotitanate as the co-precursors. The morphology, structure and composition of the monolith were characterized. In contrast to conventional boronate affinity materials, inorganic boric acid was used as affinity ligand. Different compounds were used for the evaluation of the boronate affinity of this inorganic monolithic material. The monolith exhibited good selectivity towards cis-diol containing compounds. Recovery of greater than 90% was achieved for in-needle extraction of catechol under neutral conditions. Owing to the hydrophilic property of the monolith, the procedure of affinity chromatography could be performed in aqueous solution. This monolithic in-needle device will be useful for boronate affinity extraction of small-volume samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Antiulcerogenic effects of coconut (Cocos nucifera) extract in rats.

PubMed

Nneli, R O; Woyike, O A

2008-07-01

A warm water crude extract of coconut milk and a coconut water dispersion were investigated for their antiulcerogenic effects in male Wistar albino rats. Ulcers were induced in the male rats by subcutaneous administration of indomethacin (40 mg/kg) using standard procedures. The ulcer inhibition rate (UIR) was taken as a measure of the cytoprotection offered by test substances. Coconut milk (2 mL daily oral feeding) produced a stronger percentage (54%) reduction in the mean ulcer area than coconut water (39%). The effect of coconut milk was similar to the effect of sucralfate that reduced the mean ulcer area by 56% in this study. Sucralfate is a conventional cytoprotective agent. The results showed that coconut milk and water via macroscopic observation had protective effects on the ulcerated gastric mucosa. It is concluded that coconut milk offered stronger protection on indomethacin-induced ulceration than coconut water in rats.

15 CFR 717.1 - Clarification procedures; challenge inspection requests pursuant to Article IX of the Convention.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Clarification procedures; challenge... COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS CWC CLARIFICATION PROCEDURES (CONSULTATIONS AND CHALLENGE INSPECTIONS) § 717.1 Clarification procedures; challenge inspection requests pursuant to Article IX of the...

Generating patient-specific pulmonary vascular models for surgical planning

NASA Astrophysics Data System (ADS)

Murff, Daniel; Co-Vu, Jennifer; O'Dell, Walter G.

2015-03-01

Each year in the U.S., 7.4 million surgical procedures involving the major vessels are performed. Many of our patients require multiple surgeries, and many of the procedures include "surgical exploration". Procedures of this kind come with a significant amount of risk, carrying up to a 17.4% predicted mortality rate. This is especially concerning for our target population of pediatric patients with congenital abnormalities of the heart and major pulmonary vessels. This paper offers a novel approach to surgical planning which includes studying virtual and physical models of pulmonary vasculature of an individual patient before operation obtained from conventional 3D X-ray computed tomography (CT) scans of the chest. These models would provide clinicians with a non-invasive, intricately detailed representation of patient anatomy, and could reduce the need for invasive planning procedures such as exploratory surgery. Researchers involved in the AirPROM project have already demonstrated the utility of virtual and physical models in treatment planning of the airways of the chest. Clinicians have acknowledged the potential benefit from such a technology. A method for creating patient-derived physical models is demonstrated on pulmonary vasculature extracted from a CT scan with contrast of an adult human. Using a modified version of the NIH ImageJ program, a series of image processing functions are used to extract and mathematically reconstruct the vasculature tree structures of interest. An auto-generated STL file is sent to a 3D printer to create a physical model of the major pulmonary vasculature generated from 3D CT scans of patients.

[The anesthetic effects of Gow-Gates technique of inferior alveolar nerve block in impacted mandibular third molar extraction].

PubMed

Yang, Jieping; Liu, Wei; Gao, Qinghong

2013-08-01

To evaluate the anesthetic effects and safety of Gow-Gates technique of inferior alveolar nerve block in impacted mandibular third molar extraction. A split-mouth study was designed. The bilateral impacted mandibular third molar of 32 participants were divided into Gow-Gates technique of inferior alveolar nerve block (Gow-Gates group) and conventional technique of inferior alveolar nerve block (conventional group) randomly with third molar extracted. The anesthetic effects and adverse events were recorded. All the participants completed the research. The anesthetic success rate was 96.9% in Gow-Gates group and 90.6% in conventional group with no statistical difference ( P= 0.317); but when comparing the anesthesia grade, Gow-Gates group had a 96.9% of grade A and B, and conventional group had a rate of 78.1% (P = 0.034). And the Gow-Gates group had a much lower withdrawn bleeding than conventional group (P = 0.025). Two groups had no hematoma. Gow-Gates technique had a reliable anesthesia effects and safety in impacted mandibular third molar extraction and could be chosen as a candidate for the conventional inferior alveolar nerve block.

Adherence of Candida to complete denture surfaces in vitro: A comparison of conventional and CAD/CAM complete dentures

PubMed Central

Al-mejrad, Lamya A.; Albarrag, Ahmed M.

2017-01-01

PURPOSE The goal of this study was to compare the adhesion of Candida albicans to the surfaces of CAD/CAM and conventionally fabricated complete denture bases. MATERIALS AND METHODS Twenty discs of acrylic resin poly (methyl methacrylate) were fabricated with CAD/CAM and conventional procedures (heat-polymerized acrylic resin). The specimens were divided into two groups: 10 discs were fabricated using the CAD/CAM procedure (Wieland Digital Denture Ivoclar Vivadent), and 10 discs were fabricated using a conventional flasking and pressure-pack technique. Candida colonization was performed on all the specimens using four Candida albicans isolates. The difference in Candida albicans adhesion on the discs was evaluated. The number of adherent yeast cells was calculated by the colony-forming units (CFU) and by Fluorescence microscopy. RESULTS There was a significant difference in the adhesion of Candida albicans to the complete denture bases created with CAD/CAM and the adhesion to those created with the conventional procedure. The CAD/CAM denture bases exhibited less adhesion of Candida albicans than did the denture bases created with the conventional procedure (P<.05). CONCLUSION The CAD/CAM procedure for fabricating complete dentures showed promising potential for reducing the adherence of Candida to the denture base surface. Clinical Implications. Complete dentures made with the CAD/CAM procedure might decrease the incidence of denture stomatitis compared with conventional dentures. PMID:29142649

Adherence of Candida to complete denture surfaces in vitro: A comparison of conventional and CAD/CAM complete dentures.

PubMed

Al-Fouzan, Afnan F; Al-Mejrad, Lamya A; Albarrag, Ahmed M

2017-10-01

The goal of this study was to compare the adhesion of Candida albicans to the surfaces of CAD/CAM and conventionally fabricated complete denture bases. Twenty discs of acrylic resin poly (methyl methacrylate) were fabricated with CAD/CAM and conventional procedures (heat-polymerized acrylic resin). The specimens were divided into two groups: 10 discs were fabricated using the CAD/CAM procedure (Wieland Digital Denture Ivoclar Vivadent), and 10 discs were fabricated using a conventional flasking and pressure-pack technique. Candida colonization was performed on all the specimens using four Candida albicans isolates. The difference in Candida albicans adhesion on the discs was evaluated. The number of adherent yeast cells was calculated by the colony-forming units (CFU) and by Fluorescence microscopy. There was a significant difference in the adhesion of Candida albicans to the complete denture bases created with CAD/CAM and the adhesion to those created with the conventional procedure. The CAD/CAM denture bases exhibited less adhesion of Candida albicans than did the denture bases created with the conventional procedure ( P <.05). The CAD/CAM procedure for fabricating complete dentures showed promising potential for reducing the adherence of Candida to the denture base surface. Clinical Implications. Complete dentures made with the CAD/CAM procedure might decrease the incidence of denture stomatitis compared with conventional dentures.

Supercritical fluid extraction and ultra performance liquid chromatography of respiratory quinones for microbial community analysis in environmental and biological samples.

PubMed

Hanif, Muhammad; Atsuta, Yoichi; Fujie, Koichi; Daimon, Hiroyuki

2012-03-05

Microbial community structure plays a significant role in environmental assessment and animal health management. The development of a superior analytical strategy for the characterization of microbial community structure is an ongoing challenge. In this study, we developed an effective supercritical fluid extraction (SFE) and ultra performance liquid chromatography (UPLC) method for the analysis of bacterial respiratory quinones (RQ) in environmental and biological samples. RQ profile analysis is one of the most widely used culture-independent tools for characterizing microbial community structure. A UPLC equipped with a photo diode array (PDA) detector was successfully applied to the simultaneous determination of ubiquinones (UQ) and menaquinones (MK) without tedious pretreatment. Supercritical carbon dioxide (scCO(2)) extraction with the solid-phase cartridge trap proved to be a more effective and rapid method for extracting respiratory quinones, compared to a conventional organic solvent extraction method. This methodology leads to a successful analytical procedure that involves a significant reduction in the complexity and sample preparation time. Application of the optimized methodology to characterize microbial communities based on the RQ profile was demonstrated for a variety of environmental samples (activated sludge, digested sludge, and compost) and biological samples (swine and Japanese quail feces).

Profiling the Fatty Acids Content of Ornamental Camellia Seeds Cultivated in Galicia by an Optimized Matrix Solid-Phase Dispersion Extraction

PubMed Central

Garcia-Jares, Carmen; Sanchez-Nande, Marta; Lamas, Juan Pablo; Lores, Marta

2017-01-01

Camellia (genus of flowering plants of fam. Theaceae) is one of the main crops in Asia, where tea and oil from leaves and seeds have been utilized for thousands of years. This plant is excellently adapted to the climate and soil of Galicia (northwestern Spain) and northern Portugal where it is grown not only as an ornamental plant, but to be evaluated as a source of bioactive compounds. In this work, the main fatty acids were extracted from Camellia seeds of four varieties of Camellia: sasanqua, reticulata, japonica and sinensis, by means of matrix-solid phase dispersion (MSPD), and analyzed by gas chromatography (GC) with MS detection of the corresponding methyl esters. MSPD constitutes an efficient and greener alternative to conventional extraction techniques, moreover if it is combined with the use of green solvents such as limonene. The optimization of the MSPD extraction procedure has been conducted using a multivariate approach based on strategies of experimental design, which enabled the simultaneous evaluation of the factors influencing the extraction efficiency as well as interactions between factors. The optimized method was applied to characterize the fatty acids profiles of four Camellia varieties seeds, allowing us to compare their fatty acid composition. PMID:29039745

Minilaparotomy-Assisted Transmesenteric-Transjugular Intrahepatic Portosystemic Shunt: Comparison with Conventional Transjugular Approach

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

Jalaeian, Hamed, E-mail: hjalaeia@umn.edu; Talaie, Reza; D’Souza, Donna

PurposeThis study was performed to compare the intrahepatic shunt function outcome and procedural complications of minilaparotomy-assisted transmesenteric (MAT)-transjugular intrahepatic portosystemic shunt (TIPS) placement with the conventional transjugular method.MethodsThis is a retrospective review of all patients who had a MAT or conventional TIPS procedure over a 6-year period at our institute. The primary patency rate, fluoroscopy time, technical success, major procedure-related complications, and mortality data were compared between two treatment groups.ResultsWe included 49 patients with MAT-TIPS, and 63 with conventional TIPS, with an average follow-up of 21.43 months. The primary patency rates at 6 and 12 months were 82.9 and 66.7 % in themore » conventional TIPS group, and 81.0 and 76.5 % in the MAT-TIPS group (p = 1.000, and 0.529), respectively. There was no significant difference in technical success rate, post-procedure portosystemic pressure gradient, fluoroscopy time, and peri-procedural mortality rate between treatment groups. Major procedural-related complications were seen more frequently among MAT-TIPS patients (p = 0.012). In the MAT-TIPS group, 5 (10.2 %) patients developed post-procedure minilaparotomy, wound-related complications, and 5 (10.2 %) developed bacterial peritonitis; whereas, none of patients with conventional TIPS had either of these complications (p = 0.014).ConclusionWhile both MAT-TIPS and conventional TIPS had similar shunt primary patency rate and technical success rate, the MAT approach was associated with a significantly higher rate of minilaparotomy-related wound complications or infectious complications. These complications maybe prevented by a change in post-procedure monitoring and therapy.« less

[Study on ultrafine vibration extraction technology of Rhizoma Chuanxiong].

PubMed

Dai, Long

2009-04-01

To explore the best ultrafine vibration extraction technology of Rhizoma Chuanxiong. Using the content of ligustrazine hydrochloride and ferulic acid as determination indexes, quadrature test was used to choose extraction times, time, solvent amount and to compare with the result of conventional extraction technology. The best condition of the Rhizoma chuanxiong was with 90% ethanol of 4 times volume, extracting 2 times in 25 degrees C, 15 minutes each time. Comparing with conventional extraction technology, extraction time of UVET was 1/6, solvent amount was 4/7, the extraction rate of marker components was 1.19 and 1.09 times, respectivley. UVET can improve the extracting rate of effective constituents, reduce the time and solvent amount and be used in industrialization.

Conventional and accelerated-solvent extractions of green tea (camellia sinensis) for metabolomics-based chemometrics.

PubMed

Kellogg, Joshua J; Wallace, Emily D; Graf, Tyler N; Oberlies, Nicholas H; Cech, Nadja B

2017-10-25

Metabolomics has emerged as an important analytical technique for multiple applications. The value of information obtained from metabolomics analysis depends on the degree to which the entire metabolome is present and the reliability of sample treatment to ensure reproducibility across the study. The purpose of this study was to compare methods of preparing complex botanical extract samples prior to metabolomics profiling. Two extraction methodologies, accelerated solvent extraction and a conventional solvent maceration, were compared using commercial green tea [Camellia sinensis (L.) Kuntze (Theaceae)] products as a test case. The accelerated solvent protocol was first evaluated to ascertain critical factors influencing extraction using a D-optimal experimental design study. The accelerated solvent and conventional extraction methods yielded similar metabolite profiles for the green tea samples studied. The accelerated solvent extraction yielded higher total amounts of extracted catechins, was more reproducible, and required less active bench time to prepare the samples. This study demonstrates the effectiveness of accelerated solvent as an efficient methodology for metabolomics studies. Copyright © 2017. Published by Elsevier B.V.

Multi-stir bar sorptive extraction for analysis of odor compounds in aqueous samples.

PubMed

Ochiai, Nobuo; Sasamoto, Kikuo; Ieda, Teruyo; David, Frank; Sandra, Pat

2013-11-08

As reproducible coating of stir bars with more polar phases was found to be very difficult, a supporting grid was used in the development of an ethyleneglycol-modified Silicone (EG Silicone) coated stir bar. This new polar coating showed good performance for the extraction of polar solutes, but long term use also showed degradation of the coating due to friction while stirring. In order to address the lower robustness of the EG Silicone stir bar which has a much softer coating compared to a conventional polydimethylsiloxane (PDMS) stir bar, a novel SBSE procedure termed multi-SBSE ((m)SBSE) was developed. (m)SBSE consists of the robust PDMS stir bar stirring at the bottom of the vial and the EG Silicone stir bar attached on the inner side wall of the vial (a magnetic clip is used for the set-up). After extraction, the two stir bars are placed in a single glass desorption liner and are simultaneously thermally desorbed. The desorbed compounds were analyzed by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Compared to conventional SBSE, (m)SBSE provides more uniform enrichment of a wide range of odor compounds in aqueous sample since both stir bars can complement each other, while eliminating the damage of the EG Silicone phase during the extraction. The robustness of the EG Silicone stir bar was dramatically increased and more than 30 extraction and desorption cycles were possible without loss in performance. The recoveries for polar solutes such as 2-acetyl pyrrole (logKow: 0.55), benzyl alcohol (logKow: 1.08), guaiacol (logKow: 1.34), and indole (logKow: 2.05) were increased by a factor of about 2-7. The (m)SBSE-TD-GC-MS method showed good linearity (r(2)>0.9913) and high sensitivity (limit of detection: 0.011-0.071 ng mL(-1)) for the test compounds spiked in water. The feasibility and benefit of the method was demonstrated with analysis of odor compounds in roasted green tea. The normalized areas obtained from (m)SBSE showed the best enrichment for most of the selected compounds compared to conventional SBSE using the PDMS stir bar or the EG Silicone stir bar. Fifteen compounds were determined in the range of 0.15-210 ng mL(-1) (RSD<14%, n=6). Copyright © 2013 Elsevier B.V. All rights reserved.

Sequence analysis of the canine mitochondrial DNA control region from shed hair samples in criminal investigations.

PubMed

Berger, C; Berger, B; Parson, W

2012-01-01

In recent years, evidence from domestic dogs has increasingly been analyzed by forensic DNA testing. Especially, canine hairs have proved most suitable and practical due to the high rate of hair transfer occurring between dogs and humans. Starting with the description of a contamination-free sample handling procedure, we give a detailed workflow for sequencing hypervariable segments (HVS) of the mtDNA control region from canine evidence. After the hair material is lysed and the DNA extracted by Phenol/Chloroform, the amplification and sequencing strategy comprises the HVS I and II of the canine control region and is optimized for DNA of medium-to-low quality and quantity. The sequencing procedure is based on the Sanger Big-dye deoxy-terminator method and the separation of the sequencing reaction products is performed on a conventional multicolor fluorescence detection capillary electrophoresis platform. Finally, software-aided base calling and sequence interpretation are addressed exemplarily.

Magnetic particles as powerful purification tool for high sensitive mass spectrometric screening procedures.

PubMed

Peter, Jochen F; Otto, Angela M

2010-02-01

The effective isolation and purification of proteins from biological fluids is the most crucial step for a successful protein analysis when only minute amounts are available. While conventional purification methods such as dialysis, ultrafiltration or protein precipitation often lead to a marked loss of protein, SPE with small-sized particles is a powerful alternative. The implementation of particles with superparamagnetic cores facilitates the handling of those particles and allows the application of particles in the nanometer to low micrometer range. Due to the small diameters, magnetic particles are advantageous for increasing sensitivity when using subsequent MS analysis or gel electrophoresis. In the last years, different types of magnetic particles were developed for specific protein purification purposes followed by analysis or screening procedures using MS or SDS gel electrophoresis. In this review, the use of magnetic particles for different applications, such as, the extraction and analysis of DNA/RNA, peptides and proteins, is described.

High strength air-dried aerogels

DOEpatents

Coronado, Paul R.; Satcher, Jr., Joe H.

2012-11-06

A method for the preparation of high strength air-dried organic aerogels. The method involves the sol-gel polymerization of organic gel precursors, such as resorcinol with formaldehyde (RF) in aqueous solvents with R/C ratios greater than about 1000 and R/F ratios less than about 1:2.1. Using a procedure analogous to the preparation of resorcinol-formaldehyde (RF) aerogels, this approach generates wet gels that can be air dried at ambient temperatures and pressures. The method significantly reduces the time and/or energy required to produce a dried aerogel compared to conventional methods using either supercritical solvent extraction. The air dried gel exhibits typically less than 5% shrinkage.

Microextraction by packed sorbent: an emerging, selective and high-throughput extraction technique in bioanalysis.

PubMed

Pereira, Jorge; Câmara, José S; Colmsjö, Anders; Abdel-Rehim, Mohamed

2014-06-01

Sample preparation is an important analytical step regarding the isolation and concentration of desired components from complex matrices and greatly influences their reliable and accurate analysis and data quality. It is the most labor-intensive and error-prone process in analytical methodology and, therefore, may influence the analytical performance of the target analytes quantification. Many conventional sample preparation methods are relatively complicated, involving time-consuming procedures and requiring large volumes of organic solvents. Recent trends in sample preparation include miniaturization, automation, high-throughput performance, on-line coupling with analytical instruments and low-cost operation through extremely low volume or no solvent consumption. Micro-extraction techniques, such as micro-extraction by packed sorbent (MEPS), have these advantages over the traditional techniques. This paper gives an overview of MEPS technique, including the role of sample preparation in bioanalysis, the MEPS description namely MEPS formats (on- and off-line), sorbents, experimental and protocols, factors that affect the MEPS performance, and the major advantages and limitations of MEPS compared with other sample preparation techniques. We also summarize MEPS recent applications in bioanalysis. Copyright © 2014 John Wiley & Sons, Ltd.

Classification of pulmonary pathology from breath sounds using the wavelet packet transform and an extreme learning machine.

PubMed

Palaniappan, Rajkumar; Sundaraj, Kenneth; Sundaraj, Sebastian; Huliraj, N; Revadi, S S

2017-06-08

Auscultation is a medical procedure used for the initial diagnosis and assessment of lung and heart diseases. From this perspective, we propose assessing the performance of the extreme learning machine (ELM) classifiers for the diagnosis of pulmonary pathology using breath sounds. Energy and entropy features were extracted from the breath sound using the wavelet packet transform. The statistical significance of the extracted features was evaluated by one-way analysis of variance (ANOVA). The extracted features were inputted into the ELM classifier. The maximum classification accuracies obtained for the conventional validation (CV) of the energy and entropy features were 97.36% and 98.37%, respectively, whereas the accuracies obtained for the cross validation (CRV) of the energy and entropy features were 96.80% and 97.91%, respectively. In addition, maximum classification accuracies of 98.25% and 99.25% were obtained for the CV and CRV of the ensemble features, respectively. The results indicate that the classification accuracy obtained with the ensemble features was higher than those obtained with the energy and entropy features.

Electronic simulation of the supported liquid membrane in electromembrane extraction systems: Improvement of the extraction by precise periodical reversing of the field polarity.

PubMed

Moazami, Hamid Reza; Nojavan, Saeed; Zahedi, Pegah; Davarani, Saied Saeed Hosseiny

2014-09-02

In order to understand the limitations of electromebrane extraction procedure better, a simple equivalent circuit has been proposed for a supported liquid membrane consisting of a resistor and a low leakage capacitor in series. To verify the equivalent circuit, it was subjected to a simulated periodical polarity changing potential and the resulting time variation of the current was compared with that of a real electromembrane extraction system. The results showed a good agreement between the simulated current patterns and those of the real ones. In order to investigate the impact of various limiting factors, the corresponding values of the equivalent circuit were estimated for a real electromembrane extraction system and were attributed to the physical parameters of the extraction system. A dual charge transfer mechanism was proposed for electromembrane extraction by combining general migration equation and fundamental aspects derived from the simulation. Dual mechanism comprises a current dependent contribution of analyte in total current and could support the possibility of an improvement in performance of an electromembrane extraction by application of an asymmetric polarity changing potential. The optimization of frequency and duty cycle of the asymmetric polarity exchanging potential resulted in a higher recovery (2.17 times greater) in comparison with the conventional electromebrane extraction. The simulation also provided more quantitative approaches toward the investigation of the mechanism of extraction and contribution of different limiting factors in electromembrane extraction. Results showed that the buildup of the double layer is the main limiting factor and the Joule heating has lesser impact on the performance of an electromebrane extraction system. Copyright © 2014 Elsevier B.V. All rights reserved.

Back to basics: an evaluation of NaOH and alternative rapid DNA extraction protocols for DNA barcoding, genotyping, and disease diagnostics from fungal and oomycete samples.

PubMed

Osmundson, Todd W; Eyre, Catherine A; Hayden, Katherine M; Dhillon, Jaskirn; Garbelotto, Matteo M

2013-01-01

The ubiquity, high diversity and often-cryptic manifestations of fungi and oomycetes frequently necessitate molecular tools for detecting and identifying them in the environment. In applications including DNA barcoding, pathogen detection from plant samples, and genotyping for population genetics and epidemiology, rapid and dependable DNA extraction methods scalable from one to hundreds of samples are desirable. We evaluated several rapid extraction methods (NaOH, Rapid one-step extraction (ROSE), Chelex 100, proteinase K) for their ability to obtain DNA of quantity and quality suitable for the following applications: PCR amplification of the multicopy barcoding locus ITS1/5.8S/ITS2 from various fungal cultures and sporocarps; single-copy microsatellite amplification from cultures of the phytopathogenic oomycete Phytophthora ramorum; probe-based P. ramorum detection from leaves. Several methods were effective for most of the applications, with NaOH extraction favored in terms of success rate, cost, speed and simplicity. Frozen dilutions of ROSE and NaOH extracts maintained PCR viability for over 32 months. DNA from rapid extractions performed poorly compared to CTAB/phenol-chloroform extracts for TaqMan diagnostics from tanoak leaves, suggesting that incomplete removal of PCR inhibitors is an issue for sensitive diagnostic procedures, especially from plants with recalcitrant leaf chemistry. NaOH extracts exhibited lower yield and size than CTAB/phenol-chloroform extracts; however, NaOH extraction facilitated obtaining clean sequence data from sporocarps contaminated by other fungi, perhaps due to dilution resulting from low DNA yield. We conclude that conventional extractions are often unnecessary for routine DNA sequencing or genotyping of fungi and oomycetes, and recommend simpler strategies where source materials and intended applications warrant such use. © 2012 Blackwell Publishing Ltd.

Rapid preparation of nuclei-depleted detergent-resistant membrane fractions suitable for proteomics analysis.

PubMed

Adam, Rosalyn M; Yang, Wei; Di Vizio, Dolores; Mukhopadhyay, Nishit K; Steen, Hanno

2008-06-05

Cholesterol-rich membrane microdomains known as lipid rafts have been implicated in diverse physiologic processes including lipid transport and signal transduction. Lipid rafts were originally defined as detergent-resistant membranes (DRMs) due to their relative insolubility in cold non-ionic detergents. Recent findings suggest that, although DRMs are not equivalent to lipid rafts, the presence of a given protein within DRMs strongly suggests its potential for raft association in vivo. Therefore, isolation of DRMs represents a useful starting point for biochemical analysis of lipid rafts. The physicochemical properties of DRMs present unique challenges to analysis of their protein composition. Existing methods of isolating DRM-enriched fractions involve flotation of cell extracts in a sucrose density gradient, which, although successful, can be labor intensive, time consuming and results in dilute sucrose-containing fractions with limited utility for direct proteomic analysis. In addition, several studies describing the proteomic characterization of DRMs using this and other approaches have reported the presence of nuclear proteins in such fractions. It is unclear whether these results reflect trafficking of nuclear proteins to DRMs or whether they arise from nuclear contamination during isolation. To address these issues, we have modified a published differential detergent extraction method to enable rapid DRM isolation that minimizes nuclear contamination and yields fractions compatible with mass spectrometry. DRM-enriched fractions isolated using the conventional or modified extraction methods displayed comparable profiles of known DRM-associated proteins, including flotillins, GPI-anchored proteins and heterotrimeric G-protein subunits. Thus, the modified procedure yielded fractions consistent with those isolated by existing methods. However, we observed a marked reduction in the percentage of nuclear proteins identified in DRM fractions isolated with the modified method (15%) compared to DRMs isolated by conventional means (36%). Furthermore, of the 21 nuclear proteins identified exclusively in modified DRM fractions, 16 have been reported to exist in other subcellular sites, with evidence to suggest shuttling of these species between the nucleus and other organelles. We describe a modified DRM isolation procedure that generates DRMs that are largely free of nuclear contamination and that is compatible with downstream proteomic analyses with minimal additional processing. Our findings also imply that identification of nuclear proteins in DRMs is likely to reflect legitimate movement of proteins between compartments, and is not a result of contamination during extraction.

Extraction mechanism of ultrasound assisted extraction and its effect on higher yielding and purity of artemisinin crystals from Artemisia annua L. leaves.

PubMed

Chemat, Smain; Aissa, Abdallah; Boumechhour, Abdenour; Arous, Omar; Ait-Amar, Hamid

2017-01-01

This study proposes an ultrasound-horn system for the extraction of a natural active compound "artemisinin" from Artemisia annua L. leaves as an alternative to hot maceration technique. Ultrasound leaching improves artemisinin recovery at all temperatures where only ten minutes is required to recover 70% (4.42mgg -1 ) compared to 60min of conventional hot leaching for the same yield. For instance, ultrasound treatment at 30°C produced a higher yield than the one obtained by conventional maceration at 40°C. Kinetic study suggests that the extraction pattern can be assimilated, during the first ten minutes, to a first order steady state, from which activation energy calculations revealed that each gram of artemisinin required 7.38kJ in ultrasound versus 10.3kJ in the conventional system. Modeling results indicate the presence of two extraction stages, a faster stage with a diffusion coefficient of 19×10 -5 cm 2 min -1 for ultrasound technique at 40°C, seven times higher than the conventional one; and a second deceleration stage similar for both techniques with diffusion coefficient ranging from 1.7 to 3.1×10 -5 cm 2 min -1 . It is noted that the efficient ultrasound extraction potential implies extraction of higher amount of co-metabolites so low artemisinin crystal purity is engendered but a combination with a purification step using activated charcoal and celite adsorbents produced crystals with comparable purity for conventional and ultrasound samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Epithelial structure revealed by chemical dissection and unembedded electron microscopy.

PubMed

Fey, E G; Capco, D G; Krochmalnic, G; Penman, S

1984-07-01

Cytoskeletal structures obtained after extraction of Madin-Darby canine kidney epithelial cell monolayers with Triton X-100 were examined in transmission electron micrographs of cell whole mounts and unembedded thick sections. The cytoskeleton, an ordered structure consisting of a peripheral plasma lamina, a complex network of filaments, and chromatin-containing nuclei, was revealed after extraction of intact cells with a nearly physiological buffer containing Triton X-100. The cytoskeleton was further fractionated by extraction with (NH4)2SO4, which left a structure enriched in intermediate filaments and desmosomes around the nuclei. A further digestion with nuclease and elution with (NH4)2SO4 removed the chromatin. The stable structure that remained after this procedure retained much of the epithelial morphology and contained essentially all of the cytokeratin filaments and desmosomes and the chromatin-depleted nuclear matrices. This structural network may serve as a scaffold for epithelial organization. The cytoskeleton and the underlying nuclear matrix intermediate filament scaffold, when examined in both conventional embedded thin sections and in unembedded whole mounts and thick sections, showed the retention of many of the detailed morphological aspects of the intact cells, which suggests a structural continuum linking the nuclear matrix, the intermediate filament network, and the intercellular desmosomal junctions. Most importantly, the protein composition of each of the four fractions obtained by this sequential procedure was essentially unique. Thus, the proteins constituting the soluble fraction, the cytoskeleton, the chromatin fraction, and the underlying nuclear matrix-intermediate filament scaffold are biochemically distinct.

Epithelial structure revealed by chemical dissection and unembedded electron microscopy

PubMed Central

Fey, E. G.; Capco, D. G.; Krochmalnic, G.; Penman, S.

1984-01-01

Cytoskeletal structures obtained after extraction of Madin-Darby canine kidney epithelial cell monolayers with Triton X-100 were examined in transmission electron micrographs of cell whole mounts and unembedded thick sections. The cytoskeleton, an ordered structure consisting of a peripheral plasma lamina, a complex network of filaments, and chromatin-containing nuclei, was revealed after extraction of intact cells with a nearly physiological buffer containing Triton X-100. The cytoskeleton was further fractionated by extraction with (NH4)2SO4, which left a structure enriched in intermediate filaments and desmosomes around the nuclei. A further digestion with nuclease and elution with (NH4)2SO4 removed the chromatin. The stable structure that remained after this procedure retained much of the epithelial morphology and contained essentially all of the cytokeratin filaments and desmosomes and the chromatin-depleted nuclear matrices. This structural network may serve as a scaffold for epithelial organization. The cytoskeleton and the underlying nuclear matrix intermediate filament scaffold, when examined in both conventional embedded thin sections and in unembedded whole mounts and thick sections, showed the retention of many of the detailed morphological aspects of the intact cells, which suggests a structural continuum linking the nuclear matrix, the intermediate filament network, and the intercellular desmosomal junctions. Most importantly, the protein composition of each of the four fractions obtained by this sequential procedure was essentially unique. Thus, the proteins constituting the soluble fraction, the cytoskeleton, the chromatin fraction, and the underlying nuclear matrix-intermediate filament scaffold are biochemically distinct. PMID:6540264

Overcoming the challenges of conventional dispersive liquid-liquid microextraction: analysis of THMs in chlorinated swimming pools.

PubMed

Faraji, Hakim; Helalizadeh, Masoumeh; Kordi, Mohammad Reza

2018-01-01

A rapid, simple, and sensitive approach to the analysis of trihalomethanes (THMs) in swimming pool water samples has been developed. The main goal of this study was to overcome or to improve the shortcomings of conventional dispersive liquid-liquid microextraction (DLLME) and to maximize the realization of green analytical chemistry principles. The method involves a simple vortex-assisted microextraction step, in the absence of the dispersive solvent, followed by salting-out effect for the elimination of the centrifugation step. A bell-shaped device and a solidifiable solvent were used to simplify the extraction solvent collection after phase separation. Optimization of the independent variables was performed by using chemometric methods in three steps. The method was statistically validated based on authentic guidance documents. The completion time for extraction was less than 8 min, and the limits of detection were in the range between 4 and 72 ng L -1 . Using this method, good linearity and precision were achieved. The results of THMs determination in different real samples showed that in some cases the concentration of total THMs was more than threshold values of THMs determined by accredited healthcare organizations. This method indicated satisfactory analytical figures of merit. Graphical Abstract A novel green microextraction technique for overcoming the challenges of conventional DLLME. The proposed procedure complies with the principles of green/sustainable analytical chemistry, comprising decreasing the sample size, making easy automation of the process, reducing organic waste, diminishing energy consumption, replacing toxic reagents with safer reagents, and enhancing operator safety.

Evaluation of FTA(®) card for the rescue of infectious foot-and-mouth disease virus by chemical transfection of extracted RNA in cultured cells.

PubMed

Biswal, Jitendra K; Subramaniam, Saravanan; Ranjan, Rajeev; Pattnaik, Bramhadev

2016-08-01

Foot-and-mouth disease (FMD) is a highly contagious epidemic disease of transboundary importance. Inadequate storage and shipment of suspected clinical samples can compromise the ability to detect and characterise FMD virus (FMDV) in endemic countries, thereby, leading to the loss of valuable virological and epidemiological data. This study, investigates the potential of using FTA(®) cards for dry transportation of clinical samples and subsequent recovery of infectious FMDV by chemical transfection of FTA(®) card fixed RNA as an alternative to the conventional cell culture based virus isolation method. A higher proportion of infectious FMDV was rescued from clinical samples (cell culture isolates, tongue epithelial suspension and impression smears) by the FTA(®) card fixed RNA transfection method (76%) compared to the conventional cell culture based virus isolation (56%), suggesting a better performance of the current RNA transfection procedure. Furthermore, it was possible to rescue live virus by the transfection of RNA extracted from FTA(®) card impregnated with clinical samples that had been stored at varying temperature (4-37 °C) up to a period of six weeks. The VP1 sequence data and antigenic relationships with the vaccine strains, between viruses rescued by FTA(®) card fixed RNA transfection and conventional cell culture, were comparable. Therefore, these results support the use of the FTA(®) card for the economic, dry, non-hazardous transport of FMD suspected clinical samples from the site of collection to national/international reference laboratories. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bio-refinery of orange peels waste: a new concept based on integrated green and solvent free extraction processes using ultrasound and microwave techniques to obtain essential oil, polyphenols and pectin.

PubMed

Boukroufa, Meryem; Boutekedjiret, Chahrazed; Petigny, Loïc; Rakotomanomana, Njara; Chemat, Farid

2015-05-01

In this study, extraction of essential oil, polyphenols and pectin from orange peel has been optimized using microwave and ultrasound technology without adding any solvent but only "in situ" water which was recycled and used as solvent. The essential oil extraction performed by Microwave Hydrodiffusion and Gravity (MHG) was optimized and compared to steam distillation extraction (SD). No significant changes in yield were noticed: 4.22 ± 0.03% and 4.16 ± 0.05% for MHG and SD, respectively. After extraction of essential oil, residual water of plant obtained after MHG extraction was used as solvent for polyphenols and pectin extraction from MHG residues. Polyphenols extraction was performed by ultrasound-assisted extraction (UAE) and conventional extraction (CE). Response surface methodology (RSM) using central composite designs (CCD) approach was launched to investigate the influence of process variables on the ultrasound-assisted extraction (UAE). The statistical analysis revealed that the optimized conditions of ultrasound power and temperature were 0.956 W/cm(2) and 59.83°C giving a polyphenol yield of 50.02 mgGA/100 g dm. Compared with the conventional extraction (CE), the UAE gave an increase of 30% in TPC yield. Pectin was extracted by conventional and microwave assisted extraction. This technique gives a maximal yield of 24.2% for microwave power of 500 W in only 3 min whereas conventional extraction gives 18.32% in 120 min. Combination of microwave, ultrasound and the recycled "in situ" water of citrus peels allow us to obtain high added values compounds in shorter time and managed to make a closed loop using only natural resources provided by the plant which makes the whole process intensified in term of time and energy saving, cleanliness and reduced waste water. Copyright © 2014 Elsevier B.V. All rights reserved.

Enzyme assisted extraction of biomolecules as an approach to novel extraction technology: A review.

PubMed

Nadar, Shamraja S; Rao, Priyanka; Rathod, Virendra K

2018-06-01

An interest in the development of extraction techniques of biomolecules from various natural sources has increased in recent years due to their potential applications particularly for food and nutraceutical purposes. The presence of polysaccharides such as hemicelluloses, starch, pectin inside the cell wall, reduces the extraction efficiency of conventional extraction techniques. Conventional techniques also suffer from low extraction yields, time inefficiency and inferior extract quality due to traces of organic solvents present in them. Hence, there is a need of the green and novel extraction methods to recover biomolecules. The present review provides a holistic insight to various aspects related to enzyme aided extraction. Applications of enzymes in the recovery of various biomolecules such as polyphenols, oils, polysaccharides, flavours and colorants have been highlighted. Additionally, the employment of hyphenated extraction technologies can overcome some of the major drawbacks of enzyme based extraction such as longer extraction time and immoderate use of solvents. This review also includes hyphenated intensification techniques by coupling conventional methods with ultrasound, microwave, high pressure and supercritical carbon dioxide. The last section gives an insight on application of enzyme immobilization as a strategy for large scale extraction. Immobilization of enzymes on magnetic nanoparticles can be employed to enhance the operational performance of the system by multiple use of expensive enzymes making them industrially and economically feasible. Copyright © 2018 Elsevier Ltd. All rights reserved.

Early diagnostic of concurrent gear degradation processes progressing under time-varying loads

NASA Astrophysics Data System (ADS)

Guilbault, Raynald; Lalonde, Sébastien

2016-08-01

This study develops a gear diagnostic procedure for the detection of multi- and concurrent degradation processes evolving under time-varying loads. Instead of a conventional comparison between a descriptor and an alarm level, this procedure bases its detection strategy on a descriptor evolution tracking; a lasting descriptor increase denotes the presence of ongoing degradation mechanisms. The procedure works from time domain residual signals prepared in the frequency domain, and accepts any gear conditions as reference signature. To extract the load fluctuation repercussions, the procedure integrates a scaling factor. The investigation first examines a simplification assuming a linear connection between the load and the dynamic response amplitudes. However, while generally valuable, the precision losses associated with large load variations may mask the contribution of tiny flaws. To better reflect the real non-linear relation, the paper reformulates the scaling factor; a power law with an exponent value of 0.85 produces noticeable improvements of the load effect extraction. To reduce the consequences of remaining oscillations, the procedure also includes a filtering phase. During the validation program, a synthetic wear progression assuming a commensurate relation between the wear depth and friction assured controlled evolutions of the surface degradation influence, whereas the fillet crack growth remained entirely determined by the operation conditions. Globally, the tested conditions attest that the final strategy provides accurate monitoring of coexisting isolated damages and general surface deterioration, and that its tracking-detection capacities are unaffected by severe time variations of external loads. The procedure promptly detects the presence of evolving abnormal phenomena. The tests show that the descriptor curve shapes virtually describe the constant wear progression superimposed on the crack length evolution. At the tooth fracture, the mean values of the residual signal evince strong perturbations, while after this episode, the monitoring curves continue signaling the ongoing wear process.

Facial recognition using multisensor images based on localized kernel eigen spaces.

PubMed

Gundimada, Satyanadh; Asari, Vijayan K

2009-06-01

A feature selection technique along with an information fusion procedure for improving the recognition accuracy of a visual and thermal image-based facial recognition system is presented in this paper. A novel modular kernel eigenspaces approach is developed and implemented on the phase congruency feature maps extracted from the visual and thermal images individually. Smaller sub-regions from a predefined neighborhood within the phase congruency images of the training samples are merged to obtain a large set of features. These features are then projected into higher dimensional spaces using kernel methods. The proposed localized nonlinear feature selection procedure helps to overcome the bottlenecks of illumination variations, partial occlusions, expression variations and variations due to temperature changes that affect the visual and thermal face recognition techniques. AR and Equinox databases are used for experimentation and evaluation of the proposed technique. The proposed feature selection procedure has greatly improved the recognition accuracy for both the visual and thermal images when compared to conventional techniques. Also, a decision level fusion methodology is presented which along with the feature selection procedure has outperformed various other face recognition techniques in terms of recognition accuracy.

78 FR 21215 - Energy Conservation Program for Consumer Products: Association of Home Appliance Manufacturers...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-10

... to amend the test procedures for residential dishwashers, dehumidifiers, and conventional cooking... procedures for residential dishwashers, dehumidifiers, and conventional cooking products, go to the Federal e..., dehumidifiers, and conventional cooking products (77 FR 65942, Oct. 31, 2012) and its direct final rule to amend...

Phenolic composition, anitproliferative and anti-inflammatory properties of conventional and organic cinnamon and peppermint

USDA-ARS?s Scientific Manuscript database

Conventional and organic cinnamon and peppermint were investigated for their phenolic profile, antiproliferative, anti-inflammatory, and antioxidant properties. Accelerated solvent extraction (ASE) with 75% acetone was a better method than Soxhlet and overnight extraction for phenolic content and a...

Deep eutectic solvents as efficient solvent system for the extraction of κ-carrageenan from Kappaphycus alvarezii.

PubMed

Das, Arun Kumar; Sharma, Mukesh; Mondal, Dibyendu; Prasad, Kamalesh

2016-01-20

Three different deep eutectic solvents (DESs) prepared by the complexation of choline chloride with urea, ethylene glycol and glycerol along with their hydrated counterparts were used for the selective extraction of κ-carrageenan from Kappaphycus alvarezii. Upon comparison of the quality of the polysaccharide with the one obtained using water as extraction media as well as the one extracted using widely practiced conventional method, it was found that, the physicochemical as well as rheological properties of κ-carrageenan obtained using DESs as solvents was at par to the one obtained using conventional method and was superior in quality when compared to κ-carrageenan obtained using water as solvent. Considering the tedious nature of the extraction method employed in conventional extraction process, the DESs can be considered as suitable alternative solvents for the facile extraction of the polysaccharide directly from the seaweed. However, among the hydrated and non-hydrated DESs, the hydrated ones were found to be more effective in comparison to their non-hydrated counterparts. Copyright © 2015 Elsevier Ltd. All rights reserved.

A comparative study of the incidence of Schneiderian membrane perforations during maxillary sinus augmentation with a sonic oscillating handpiece versus a conventional turbine handpiece.

PubMed

Geminiani, Alessandro; Weitz, Daniel S; Ercoli, Carlo; Feng, Changyong; Caton, Jack G; Papadimitriou, Dimitrios E V

2015-04-01

Sonic instruments may reduce perforation rates of the schneiderian membrane during lateral window sinus augmentation procedures. This study compares the incidence of membrane perforations using a sonic handpiece with an oscillating diamond insert versus a turbine handpiece with a conventional rotary diamond stone during lateral window sinus augmentation procedures. A retrospective chart analysis identified all lateral window sinus augmentation procedures done during a defined period. Among these procedures, those performed with a sonic handpiece and an oscillating diamond insert (experimental) and those performed with a conventional turbine and rotary diamond stone (conventional) were selected for this study. Reported occurrences of sinus membrane perforations during preparation of the osteotomy and elevation of the sinus membrane, as well as postoperative complications, were recorded and compared between treatment groups. Ninety-three consecutive patients were identified for a total of 130 sinus augmentation procedures (51 conventional, 79 experimental). Schneiderian membrane perforations were noted during preparation of the lateral window osteotomy in 27.5% of the sinuses in the conventional group and 12.7% of sinuses in the experimental group. During membrane elevation, perforations were noted in 43.1% of the sinuses in the conventional group and 25.3% of sinuses in the experimental group. Both differences in perforation rates were statistically significant (p < .05). There was no statistically significant difference in postoperative complications. In this study, the use of a sonic instrument to prepare the lateral window osteotomy during sinus elevation procedures resulted in a reduced perforation rate of the Schneiderian membrane compared with the conventional turbine instrument. © 2013 Wiley Periodicals, Inc.

Turbulent flow chromatography TFC-tandem mass spectrometry supporting in vitro/vivo studies of NCEs in high throughput fashion.

PubMed

Verdirame, Maria; Veneziano, Maria; Alfieri, Anna; Di Marco, Annalise; Monteagudo, Edith; Bonelli, Fabio

2010-03-11

Turbulent Flow Chromatography (TFC) is a powerful approach for on-line extraction in bioanalytical studies. It improves sensitivity and reduces sample preparation time, two factors that are of primary importance in drug discovery. In this paper the application of the ARIA system to the analytical support of in vivo pharmacokinetics (PK) and in vitro drug metabolism studies is described, with an emphasis in high throughput optimization. For PK studies, a comparison between acetonitrile plasma protein precipitation (APPP) and TFC was carried out. Our optimized TFC methodology gave better S/N ratios and lower limit of quantification (LOQ) than conventional procedures. A robust and high throughput analytical method to support hepatocyte metabolic stability screening of new chemical entities was developed by hyphenation of TFC with mass spectrometry. An in-loop dilution injection procedure was implemented to overcome one of the main issues when using TFC, that is the early elution of hydrophilic compounds that renders low recoveries. A comparison between off-line solid phase extraction (SPE) and TFC was also carried out, and recovery, sensitivity (LOQ), matrix effect and robustness were evaluated. The use of two parallel columns in the configuration of the system provided a further increase of the throughput. Copyright 2009 Elsevier B.V. All rights reserved.

Performance of conventionally powered vehicles tested to an electric vehicle test procedure

NASA Technical Reports Server (NTRS)

Slavik, R. J.; Dustin, M. O.; Lumannick, S.

1977-01-01

A conventional Volkswagen transporter, a Renault 5, a Pacer, and a U. S. Postal Service general DJ-5 delivery van were treated to an electric vehicle test procedure in order to allow direct comparison of conventional and electric vehicles. Performance test results for the four vehicles are presented.

Ionic liquid-based ultrasonic/microwave-assisted extraction combined with UPLC-MS-MS for the determination of tannins in Galla chinensis.

PubMed

Lu, Chunxia; Wang, Hongxin; Lv, Wenping; Ma, Chaoyang; Lou, Zaixiang; Xie, Jun; Liu, Bo

2012-01-01

Ionic liquid was used as extraction solvents and applied to the extraction of tannins from Galla chinensis in the simultaneous ultrasonic- and microwave-assisted extraction (UMAE) technique. Several parameters of UMAE were optimised, and the results were compared with of the conventional extraction techniques. Under optimal conditions, the content of tannins was 630.2 ± 12.1 mg g⁻¹. Compared with the conventional heat-reflux extraction, maceration extraction, regular ultrasound- and microwave-assisted extraction, the proposed approach exhibited higher efficiency (11.7-22.0% enhanced) and shorter extraction time (from 6 h to 1 min). The tannins were then identified by ultraperformance liquid chromatography tandem mass spectrometry. This study suggests that ionic liquid-based UMAE is an efficient, rapid, simple and green sample preparation technique.

Expandable Micro-motor Bur, design of a new device for least invasive extraction of broken teeth roots

PubMed Central

2013-01-01

Background Extraction of a broken tooth root is often a traumatic experience for both the practitioner and the patient. To extract broken roots, generally invasive approaches as open window surgeries or mucoperiosteal flap and/or removal of buccal bone are performed. Presentation of the hypothesis Expandable micro-motor bur (EMB) is a hypothetical design of a dental instrument proposed for removal of broken teeth roots that cannot be extracted by the routine closed methods and in which common instrumentations cannot afford to accomplish. Implication of EMB would introduce a new technique in removal of broken teeth roots in which surgical trauma is minimized and so post-extraction disorders. It would eliminate surgical invasion to the surrounding tissues; and also it would eliminate profound hand forces by the practitioner, consequently reduces stress for both the practitioner and the patient. It would eliminate high risk aftermaths such as operative morbidity (due to bone loss), maxillary sinus exposure and probable need for additional surgery as are indicative of some conventional open access approaches. Testing the hypothesis Further studies are needed to confirm its effect in clinical cases. The effectiveness of EMB should be verified firstly by animal experiments. The likelihood of its negative influence on nearby vascular and nerve system should be well evaluated. Implications of the hypothesis Implication of EMB would be of interest to both patients and the surgeon due to the following main achievements: a) no need for mucoperiosteal flap, hence preservation of soft tissue, b) no need for osteotomy, hence retention of buccal bone, c) less risk of sinus exposure, d) minimum chance of post operative infections due to eliminated surgeries in soft tissues and bones and e) in terms of esthetics, it will have a special meaning for immediate placement of dental implants. EMB’s structural components include Bur head, Spacers and Bur base. A micro motor would power its spin. In contrast to conventional surgical approaches, EMB procedure is conservative. It is anticipated that EMB would provide less traumatic and least post-operative complications in extraction of broken teeth roots. PMID:23497515

Preparative isolation and purification of hainanmurpanin, meranzin, and phebalosin from leaves of Murraya exotica L. using supercritical fluid extraction combined with consecutive high-speed countercurrent chromatography.

PubMed

Yan, Rongwei; Shen, Jie; Liu, Xiaojing; Zou, Yong; Xu, Xinjun

2018-05-01

The objective of this study was to develop a consecutive preparation method for the isolation and purification of hainanmurpanin, meranzin, and phebalosin from leaves of Murraya exotica L. The process involved supercritical fluid extraction with CO 2 , solvent extraction, and two-step high-speed countercurrent chromatography. Pressure, temperature, and the volume of entrainer were optimized as 27 MPa, 52°C, and 60 mL by response surface methodology in supercritical fluid extraction with CO 2 , and the yield of the crude extracts was 7.91 g from 100 g of leaves. Subsequently, 80% methanol/water was used to extract and condense the three compounds from the crude extracts, and 4.23 g of methanol/water extracts was obtained. Then, a two-step high-speed countercurrent chromatography procedure was developed for the isolation of the three target compounds from methanol/water extracts, including conventional high-speed countercurrent chromatography for further enrichment and consecutive high-speed countercurrent chromatography for purification. The yield of concentrates from high-speed countercurrent chromatography was 2.50 g from 4.23 g of methanol/water extracts. Finally, the consecutive high-speed countercurrent chromatography produced 103.2 mg of hainanmurpanin, 244.7 mg of meranzin, and 255.4 mg of phebalosin with purities up to 97.66, 99.36, and 98.64%, respectively, from 900 mg of high-speed countercurrent chromatography concentrates in one run of three consecutive sample loadings without exchanging a solvent system. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Linear MALDI-ToF simultaneous spectrum deconvolution and baseline removal.

PubMed

Picaud, Vincent; Giovannelli, Jean-Francois; Truntzer, Caroline; Charrier, Jean-Philippe; Giremus, Audrey; Grangeat, Pierre; Mercier, Catherine

2018-04-05

Thanks to a reasonable cost and simple sample preparation procedure, linear MALDI-ToF spectrometry is a growing technology for clinical microbiology. With appropriate spectrum databases, this technology can be used for early identification of pathogens in body fluids. However, due to the low resolution of linear MALDI-ToF instruments, robust and accurate peak picking remains a challenging task. In this context we propose a new peak extraction algorithm from raw spectrum. With this method the spectrum baseline and spectrum peaks are processed jointly. The approach relies on an additive model constituted by a smooth baseline part plus a sparse peak list convolved with a known peak shape. The model is then fitted under a Gaussian noise model. The proposed method is well suited to process low resolution spectra with important baseline and unresolved peaks. We developed a new peak deconvolution procedure. The paper describes the method derivation and discusses some of its interpretations. The algorithm is then described in a pseudo-code form where the required optimization procedure is detailed. For synthetic data the method is compared to a more conventional approach. The new method reduces artifacts caused by the usual two-steps procedure, baseline removal then peak extraction. Finally some results on real linear MALDI-ToF spectra are provided. We introduced a new method for peak picking, where peak deconvolution and baseline computation are performed jointly. On simulated data we showed that this global approach performs better than a classical one where baseline and peaks are processed sequentially. A dedicated experiment has been conducted on real spectra. In this study a collection of spectra of spiked proteins were acquired and then analyzed. Better performances of the proposed method, in term of accuracy and reproductibility, have been observed and validated by an extended statistical analysis.

76 FR 39039 - Establishment of a New Drug Code for Marihuana Extract

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-05

... that have been derived from any plant of the genus cannabis and which contain cannabinols and... Nations Conventions on international drug control treat extracts from the cannabis plant differently than.... Cannabis and cannabis resin are listed in both schedule IV and schedule I of the Single Convention...

High-throughput STR analysis for DNA database using direct PCR.

PubMed

Sim, Jeong Eun; Park, Su Jeong; Lee, Han Chul; Kim, Se-Yong; Kim, Jong Yeol; Lee, Seung Hwan

2013-07-01

Since the Korean criminal DNA database was launched in 2010, we have focused on establishing an automated DNA database profiling system that analyzes short tandem repeat loci in a high-throughput and cost-effective manner. We established a DNA database profiling system without DNA purification using a direct PCR buffer system. The quality of direct PCR procedures was compared with that of conventional PCR system under their respective optimized conditions. The results revealed not only perfect concordance but also an excellent PCR success rate, good electropherogram quality, and an optimal intra/inter-loci peak height ratio. In particular, the proportion of DNA extraction required due to direct PCR failure could be minimized to <3%. In conclusion, the newly developed direct PCR system can be adopted for automated DNA database profiling systems to replace or supplement conventional PCR system in a time- and cost-saving manner. © 2013 American Academy of Forensic Sciences Published 2013. This article is a U.S. Government work and is in the public domain in the U.S.A.

Coupling of ultrasound-assisted extraction and expanded bed adsorption for simplified medicinal plant processing and its theoretical model: extraction and enrichment of ginsenosides from Radix Ginseng as a case study.

PubMed

Mi, Jianing; Zhang, Min; Zhang, Hongyang; Wang, Yuerong; Wu, Shikun; Hu, Ping

2013-02-01

A high-efficient and environmental-friendly method for the preparation of ginsenosides from Radix Ginseng using the method of coupling of ultrasound-assisted extraction with expanded bed adsorption is described. Based on the optimal extraction conditions screened by surface response methodology, ginsenosides were extracted and adsorbed, then eluted by the two-step elution protocol. The comparison results between the coupling of ultrasound-assisted extraction with expanded bed adsorption method and conventional method showed that the former was better than the latter in both process efficiency and greenness. The process efficiency and energy efficiency of the coupling of ultrasound-assisted extraction with expanded bed adsorption method rapidly increased by 1.4-fold and 18.5-fold of the conventional method, while the environmental cost and CO(2) emission of the conventional method were 12.9-fold and 17.0-fold of the new method. Furthermore, the theoretical model for the extraction of targets was derived. The results revealed that the theoretical model suitably described the process of preparing ginsenosides by the coupling of ultrasound-assisted extraction with expanded bed adsorption system. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phytochemical profile and anticholinesterase and antimicrobial activities of supercritical versus conventional extracts of Satureja montana.

PubMed

Silva, Filipa V M; Martins, Alice; Salta, Joana; Neng, Nuno R; Nogueira, José M F; Mira, Delfina; Gaspar, Natália; Justino, Jorge; Grosso, Clara; Urieta, José S; Palavra, António M S; Rauter, Amélia P

2009-12-23

Winter savory Satureja montana is a medicinal herb used in traditional gastronomy for seasoning meats and salads. This study reports a comparison between conventional (hydrodistillation, HD, and Soxhlet extraction, SE) and alternative (supercritical fluid extraction, SFE) extraction methods to assess the best option to obtain bioactive compounds. Two different types of extracts were tested, the volatile (SFE-90 bar, second separator vs HD) and the nonvolatile fractions (SFE-250 bar, first and second separator vs SE). The inhibitory activity over acetyl- and butyrylcholinesterase by S. montana extracts was assessed as a potential indicator for the control of Alzheimer's disease. The supercritical nonvolatile fractions, which showed the highest content of (+)-catechin, chlorogenic, vanillic, and protocatechuic acids, also inhibited selectively and significantly butyrylcholinesterase, whereas the nonvolatile conventional extract did not affect this enzyme. Microbial susceptibility tests revealed the great potential of S. montana volatile supercritical fluid extract for the growth control and inactivation of Bacillus subtilis and Bacillus cereus, showing some activity against Botrytis spp. and Pyricularia oryzae. Although some studies were carried out on S. montana, the phytochemical analysis together with the biological properties, namely, the anticholinesterase and antimicrobial activities of the plant nonvolatile and volatile supercritical fluid extracts, are described herein for the first time.

Rapid method for determination of 90Sr in seawater by liquid scintillation counting with an extractive scintillator.

PubMed

Uesugi, Masaki; Watanabe, Ryosuke; Sakai, Hiroaki; Yokoyama, Akihiko

2018-02-01

A rapid determination method of 90 Sr is developed for the monitoring of seawater around the Fukushima Daiichi Nuclear Power Plant (FDNPP). Three ideas of chemical separation and measurements to accelerate 90 Sr analysis are investigated. Strontium is co-precipitated in a two-step procedure with hydroxyapatite after the removal of magnesium phosphate in the presence of citric acid. The purification process of strontium is in combination with solid phase extraction disks. One or two sheets of Sr Rad disk and cyclic operations are examined to eliminate interfering substances and secure the exchange capacity. The suitable conditions of adsorption and stripping are determined with a 85 Sr tracer. Seawater samples up to 1L can be analyzed within 4h. Additionally, the appropriate pH conditions to extract strontium to the scintillator are studied, and the 90 Sr activity is assessed via liquid scintillation counting using an extractive scintillator based on the di-(2-etyl hexyl)-phosphoric acid (HDEHP) extraction method. The new scintillation counting method involves a small quenching effect and a low background compared to the conventional emulsion scintillator method. The minimum detectable activity (MDA) is 35mBq/L of 90 Sr in 180min of counting. The proposed method provides analytical results within a day after receipt of the samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Waveform fitting and geometry analysis for full-waveform lidar feature extraction

NASA Astrophysics Data System (ADS)

Tsai, Fuan; Lai, Jhe-Syuan; Cheng, Yi-Hsiu

2016-10-01

This paper presents a systematic approach that integrates spline curve fitting and geometry analysis to extract full-waveform LiDAR features for land-cover classification. The cubic smoothing spline algorithm is used to fit the waveform curve of the received LiDAR signals. After that, the local peak locations of the waveform curve are detected using a second derivative method. According to the detected local peak locations, commonly used full-waveform features such as full width at half maximum (FWHM) and amplitude can then be obtained. In addition, the number of peaks, time difference between the first and last peaks, and the average amplitude are also considered as features of LiDAR waveforms with multiple returns. Based on the waveform geometry, dynamic time-warping (DTW) is applied to measure the waveform similarity. The sum of the absolute amplitude differences that remain after time-warping can be used as a similarity feature in a classification procedure. An airborne full-waveform LiDAR data set was used to test the performance of the developed feature extraction method for land-cover classification. Experimental results indicate that the developed spline curve- fitting algorithm and geometry analysis can extract helpful full-waveform LiDAR features to produce better land-cover classification than conventional LiDAR data and feature extraction methods. In particular, the multiple-return features and the dynamic time-warping index can improve the classification results significantly.

Viability testing of material derived from Mycobacterium tuberculosis prior to removal from a containment level-III laboratory as part of a Laboratory Risk Assessment Program.

PubMed

Blackwood, Kym S; Burdz, Tamara V; Turenne, Christine Y; Sharma, Meenu K; Kabani, Amin M; Wolfe, Joyce N

2005-01-24

In the field of clinical mycobacteriology, Mycobacterium tuberculosis (MTB) can be a difficult organism to manipulate due to the restrictive environment of a containment level 3 (CL3) laboratory. Tests for rapid diagnostic work involving smears and molecular methods do not require CL3 practices after the organism has been rendered non-viable. While it has been assumed that after organism deactivation these techniques can be performed outside of a CL3, no conclusive study has consistently confirmed that the organisms are noninfectious after the theoretical 'deactivation' steps. Previous studies have shown that initial steps (such as heating/chemical fixation) may not consistently kill MTB organisms. An inclusive viability study (n = 226) was undertaken to determine at which point handling of culture extraction materials does not necessitate a CL3 environment. Four different laboratory protocols tested for viability included: standard DNA extractions for IS6110 fingerprinting, crude DNA preparations for PCR by boiling and mechanical lysis, protein extractions, and smear preparations. For each protocol, laboratory staff planted a proportion of the resulting material to Bactec 12B medium that was observed for growth for 8 weeks. Of the 208 isolates initially tested, 21 samples grew within the 8-week period. Sixteen (7.7%) of these yielded positive results for MTB that included samples of: deactivated culture resuspensions exposed to 80 degrees C for 20 minutes, smear preparations and protein extractions. Test procedures were consequently modified and tested again (n = 18), resulting in 0% viability. This study demonstrates that it cannot be assumed that conventional practices (i.e. smear preparation) or extraction techniques render the organism non-viable. All methodologies, new and existing, should be examined by individual laboratories to validate the safe removal of material derived from MTB to the outside of a CL3 laboratory. This process is vital to establish in house biosafety-validated practices with the aim of protecting laboratory workers conducting these procedures.

Comparison of the Antimicrobial Efficacy of the EndoVac System and Conventional Needle Irrigation in Primary Molar Root Canals.

PubMed

Buldur, Burak; Kapdan, Arife

The purpose of this study was to compare the antimicrobial efficacy of the EndoVac system and conventional needle irrigation to eliminate E faecalis in primary molar root canals. 60 extracted human primary second molar roots were instrumented up to an apical size .04/35 and randomly divided into two groups; Group 1: conventional needle (n=30) and Group 2: EndoVac (n=30), and four subgroups (two experimental subgroups; (a) 2.5% sodium hypochlorite (NaOCl) + ethylenediaminetetraacetic acid (EDTA) (n=20), (b) ozonated water (OW) + EDTA (n=20), and control groups (c) 5.25% NaOCl (n=10) and (d) saline (n=10). All roots were sterilized and then inoculated with E.faecalis. Before and after final irrigation procedures, root canals were sampled and the grown colony forming units (CFUs) were counted. Data were analyzed by Kruskall-Wallis and Mann-Whitney U tests using a 0.05 significance level. The EndoVac reduced more bacteria than the conventional needle did but it was not statistically significant (p>0.05). NaOCl alone or followed by EDTA totally eliminated bacteria. OW + EDTA showed higher reduction of bacteria but could not totally eliminate bacterias. In the context of bacterial elimination, the EndoVac was not significantly better than the conventional needle. Although, there were fewer CFU/mg when using EndoVac, there was not any statistically significant superiority to conventional needle irrigation. An OW+EDTA regimen showed antibacterial effect in the primary molar root canals but it was significantly less effective than NaOCl+EDTA.

Rapid determination of polycyclic aromatic hydrocarbons in rainwater by liquid-liquid microextraction and LC with core-shell particles column and fluorescence detection.

PubMed

Vinci, Giuliana; Antonelli, Marta L; Preti, Raffaella

2013-02-01

Liquid-liquid microextraction coupled to LC with fluorescence detection for the determination of Environmental Protection Agency's 16 priority pollutant polycyclic aromatic hydrocarbons in rainwater has been developed. The optimization of the extraction method has involved several parameters, including the comparison between an ultrasonic bath and a magnetic stirrer as extractant apparatus, the choice of the extractant solvent, and the optimization of the extraction time. Liquid-liquid microextraction gave good results in terms of recoveries (from 73.6 to 102.8% in rainwater) and repeatability, with a very simple procedure and low solvent consumption. The reported chromatographic method uses a Core-Shell technology column, with particle size <3 μm instead of classical 5-μm particles column. The resulting backpressure was below 300 bar, allowing the use of a conventional HPLC system rather than the more expensive ultrahigh performance LC (UHPLC). An average decrease of 59% in run time and 75% in eluent consumption has been obtained, compared to classical HPLC methods, keeping good separation, sensitivity, and repeatability. The proposed conditions were successfully applied to the determinations of polycyclic aromatic hydrocarbons in genuine rainwater samples. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

77 FR 70105 - Energy Conservation Program: Test Procedures for Residential Dishwashers, Dehumidifiers, and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-23

... Conservation Program: Test Procedures for Residential Dishwashers, Dehumidifiers, and Conventional Cooking... conventional cooking products under the Energy Policy and Conservation Act. DATES: The effective date of this...

Multiclass pesticide determination in olives and their processing factors in olive oil: comparison of different olive oil extraction systems.

PubMed

Amvrazi, Elpiniki G; Albanis, Triantafyllos A

2008-07-23

The processing factors (pesticide concentration found in olive oil/pesticide concentration found in olives) of azinphos methyl, chlorpyrifos, lambda-cyhalothrin, deltamethrin, diazinon, dimethoate, endosulfan, and fenthion were determined in olive oil production process in various laboratory-scale olive oil extractions based on three- or two-phase centrifugation systems in comparison with samples collected during olive oil extractions in conventional olive mills located at different olive oil production areas in Greece. Pesticide analyses were performed using a multiresidue method developed in our laboratory for the determination of different insecticides and herbicides in olive oil by solid-phase extraction techniques coupled to gas chromatography detection (electron capture detection and nitrogen phosphorus detection), optimized, and validated for olive fruits sample preparation. Processing factors were found to vary among the different pesticides studied. Water addition in the oil extraction procedure (as in a three-phase centrifugation system) was found to decrease the processing factors of dimethoate, alpha-endosulfan, diazinon, and chlorpyrifos, whereas those of fenthion, azinphos methyl, beta-endosulfan, lambda-cyhalothrin, and deltamethrin residues were not affected. The water content of olives processed was found to proportionally affect pesticide processing factors. Fenthion sulfoxide and endosulfan sulfate were the major metabolites of fenthion and endosulfan, respectively, that were detected in laboratory-produced olive oils, but only the concentration of fenthion sulfoxide was found to increase with the increase of water addition in the olive oil extraction process.

Rapid LC-MS/MS quantification of the major benzodiazepines and their metabolites on dried blood spots using a simple and cost-effective sample pretreatment.

PubMed

Déglon, Julien; Versace, François; Lauer, Estelle; Widmer, Christèle; Mangin, Patrice; Thomas, Aurélien; Staub, Christian

2012-06-01

Dried blood spots (DBS) sampling has gained popularity in the bioanalytical community as an alternative to conventional plasma sampling, as it provides numerous benefits in terms of sample collection and logistics. The aim of this work was to show that these advantages can be coupled with a simple and cost-effective sample pretreatment, with subsequent rapid LC-MS/MS analysis for quantitation of 15 benzodiazepines, six metabolites and three Z-drugs. For this purpose, a simplified offline procedure was developed that consisted of letting a 5-µl DBS infuse directly into 100 µl of MeOH, in a conventional LC vial. The parameters related to the DBS pretreatment, such as extraction time or internal standard addition, were investigated and optimized, demonstrating that passive infusion in a regular LC vial was sufficient to quantitatively extract the analytes of interest. The method was validated according to international criteria in the therapeutic concentration ranges of the selected compounds. The presented strategy proved to be efficient for the rapid analysis of the selected drugs. Indeed, the offline sample preparation was reduced to a minimum, using a small amount of organic solvent and consumables, without affecting the accuracy of the method. Thus, this approach enables simple and rapid DBS analysis, even when using a non-DBS-dedicated autosampler, while lowering the costs and environmental impact.

Automated Image Analysis of HER2 Fluorescence In Situ Hybridization to Refine Definitions of Genetic Heterogeneity in Breast Cancer Tissue

PubMed Central

Radziuviene, Gedmante; Rasmusson, Allan; Augulis, Renaldas; Lesciute-Krilaviciene, Daiva; Laurinaviciene, Aida; Clim, Eduard

2017-01-01

Human epidermal growth factor receptor 2 gene- (HER2-) targeted therapy for breast cancer relies primarily on HER2 overexpression established by immunohistochemistry (IHC) with borderline cases being further tested for amplification by fluorescence in situ hybridization (FISH). Manual interpretation of HER2 FISH is based on a limited number of cells and rather complex definitions of equivocal, polysomic, and genetically heterogeneous (GH) cases. Image analysis (IA) can extract high-capacity data and potentially improve HER2 testing in borderline cases. We investigated statistically derived indicators of HER2 heterogeneity in HER2 FISH data obtained by automated IA of 50 IHC borderline (2+) cases of invasive ductal breast carcinoma. Overall, IA significantly underestimated the conventional HER2, CEP17 counts, and HER2/CEP17 ratio; however, it collected more amplified cells in some cases below the lower limit of GH definition by manual procedure. Indicators for amplification, polysomy, and bimodality were extracted by factor analysis and allowed clustering of the tumors into amplified, nonamplified, and equivocal/polysomy categories. The bimodality indicator provided independent cell diversity characteristics for all clusters. Tumors classified as bimodal only partially coincided with the conventional GH heterogeneity category. We conclude that automated high-capacity nonselective tumor cell assay can generate evidence-based HER2 intratumor heterogeneity indicators to refine GH definitions. PMID:28752092

Automated Image Analysis of HER2 Fluorescence In Situ Hybridization to Refine Definitions of Genetic Heterogeneity in Breast Cancer Tissue.

PubMed

Radziuviene, Gedmante; Rasmusson, Allan; Augulis, Renaldas; Lesciute-Krilaviciene, Daiva; Laurinaviciene, Aida; Clim, Eduard; Laurinavicius, Arvydas

2017-01-01

Human epidermal growth factor receptor 2 gene- (HER2-) targeted therapy for breast cancer relies primarily on HER2 overexpression established by immunohistochemistry (IHC) with borderline cases being further tested for amplification by fluorescence in situ hybridization (FISH). Manual interpretation of HER2 FISH is based on a limited number of cells and rather complex definitions of equivocal, polysomic, and genetically heterogeneous (GH) cases. Image analysis (IA) can extract high-capacity data and potentially improve HER2 testing in borderline cases. We investigated statistically derived indicators of HER2 heterogeneity in HER2 FISH data obtained by automated IA of 50 IHC borderline (2+) cases of invasive ductal breast carcinoma. Overall, IA significantly underestimated the conventional HER2, CEP17 counts, and HER2/CEP17 ratio; however, it collected more amplified cells in some cases below the lower limit of GH definition by manual procedure. Indicators for amplification, polysomy, and bimodality were extracted by factor analysis and allowed clustering of the tumors into amplified, nonamplified, and equivocal/polysomy categories. The bimodality indicator provided independent cell diversity characteristics for all clusters. Tumors classified as bimodal only partially coincided with the conventional GH heterogeneity category. We conclude that automated high-capacity nonselective tumor cell assay can generate evidence-based HER2 intratumor heterogeneity indicators to refine GH definitions.

Improved solvent-free microwave extraction of essential oil from dried Cuminum cyminum L. and Zanthoxylum bungeanum Maxim.

PubMed

Wang, Ziming; Ding, Lan; Li, Tiechun; Zhou, Xin; Wang, Lu; Zhang, Hanqi; Liu, Li; Li, Ying; Liu, Zhihong; Wang, Hongju; Zeng, Hong; He, Hui

2006-01-13

Solvent-free microwave extraction (SFME) is a recently developed green technique which is performed in atmospheric conditions without adding any solvent or water. SFME has already been applied to extraction of essential oil from fresh plant materials or dried materials prior moistened. The essential oil is evaporated by the in situ water in the plant materials. In this paper, it was observed that an improved SFME, in which a kind of microwave absorption solid medium, such as carbonyl iron powders (CIP), was added and mixed with the sample, can be applied to extraction of essential oil from the dried plant materials without any pretreatment. Because the microwave absorption capacity of CIP is much better than that of water, the extraction time while using the improved SFME is no more than 30 min using a microwave power of 85 W. Compared to the conventional SFME, the advantages of improved SFME were to speed up the extraction rate and need no pretreatment. Improved SFME has been compared with conventional SFME, microwave-assisted hydrodistillation (MAHD) and conventional hydrodistillation (HD) for the extraction of essential oil from dried Cuminum cyminum L. and Zanthoxylum bungeanum Maxim. By using GC-MS system the compositions of essential oil extracted by applying four kinds of extraction methods were identified. There was no obvious difference in the quality of essential oils obtained by the four kinds of extraction methods.

Optimization of microwave-assisted extraction of flavonoids from young barley leaves

NASA Astrophysics Data System (ADS)

Gao, Tian; Zhang, Min; Fang, Zhongxiang; Zhong, Qifeng

2017-01-01

A central composite design combined with response surface methodology was utilized to optimise microwave-assisted extraction of flavonoids from young barley leaves. The results showed that using water as solvent, the optimum conditions of microwave-assisted extraction were extracted twice at 1.27 W g-1 microwave power and liquid-solid ratio 34.02 ml g-1 for 11.12 min. The maximum extraction yield of flavonoids (rutin equivalents) was 80.78±0.52%. Compared with conventional extraction method, the microwave-assisted extraction was more efficient as the extraction time was only 6.18% of conventional extraction, but the extraction yield of flavonoids was increased by 5.47%. The main flavonoid components from the young barley leaf extract were probably 33.36% of isoorientin-7-O-glueoside and 54.17% of isovitexin-7-O-glucoside, based on the HPLC-MS analysis. The barley leaf extract exhibited strong reducing power as well as the DPPH radical scavenging capacity.

Conventional, ultrasound-assisted, and accelerated-solvent extractions of anthocyanins from purple sweet potatoes.

PubMed

Cai, Zhan; Qu, Ziqian; Lan, Yu; Zhao, Shujuan; Ma, Xiaohua; Wan, Qiang; Jing, Pu; Li, Pingfan

2016-04-15

Purple sweet potatoes (PSPs) are rich in anthocyanins. In this study, we investigated the extraction efficiency of anthocyanins from PSPs using conventional extraction (CE), ultrasound-assisted extraction (UAE), and accelerated-solvent extraction (ASE). Additionally, the effects of these extraction methods on antioxidant activity and anthocyanin composition of PSP extracts were evaluated. In order of decreasing extraction efficiency, the extraction methods were ASE>UAE>CE for anthocyanins (218-244 mg/100 g DW) and CE>UAE>ASE for total phenolics (631-955 mg/100 g DW) and flavonoids (28-40 mg/100 g DW). Antioxidant activities of PSP extracts were CE≈UAE>ASE for ORAC (766-1091 mg TE/100 g DW) and ASE>CE≈UAE for FRAP (1299-1705 mg TE/100 g DW). Twelve anthocyanins were identified. ASE extracts contained more diacyl anthocyanins and less nonacyl and monoacyl anthocyanins than CE and ASE extracts (P<0.05). Copyright © 2015 Elsevier Ltd. All rights reserved.

Adaptive segmentation of cerebrovascular tree in time-of-flight magnetic resonance angiography.

PubMed

Hao, J T; Li, M L; Tang, F L

2008-01-01

Accurate segmentation of the human vasculature is an important prerequisite for a number of clinical procedures, such as diagnosis, image-guided neurosurgery and pre-surgical planning. In this paper, an improved statistical approach to extracting whole cerebrovascular tree in time-of-flight magnetic resonance angiography is proposed. Firstly, in order to get a more accurate segmentation result, a localized observation model is proposed instead of defining the observation model over the entire dataset. Secondly, for the binary segmentation, an improved Iterative Conditional Model (ICM) algorithm is presented to accelerate the segmentation process. The experimental results showed that the proposed algorithm can obtain more satisfactory segmentation results and save more processing time than conventional approaches, simultaneously.

Thermodynamics of Surfactants, Block Copolymers and Their Mixtures in Water: The Role of the Isothermal Calorimetry

PubMed Central

De Lisi, Rosario; Milioto, Stefania; Muratore, Nicola

2009-01-01

The thermodynamics of conventional surfactants, block copolymers and their mixtures in water was described to the light of the enthalpy function. The two methodologies, i.e. the van’t Hoff approach and the isothermal calorimetry, used to determine the enthalpy of micellization of pure surfactants and block copolymers were described. The van’t Hoff method was critically discussed. The aqueous copolymer+surfactant mixtures were analyzed by means of the isothermal titration calorimetry and the enthalpy of transfer of the copolymer from the water to the aqueous surfactant solutions. Thermodynamic models were presented to show the procedure to extract straightforward molecular insights from the bulk properties. PMID:19742173

A comparison study on microwave-assisted extraction of Artemisia sphaerocephala polysaccharides with conventional method: Molecule structure and antioxidant activities evaluation.

PubMed

Wang, Junlong; Zhang, Ji; Wang, Xiaofang; Zhao, Baotang; Wu, Yiqian; Yao, Jian

2009-12-01

The conventional extraction methods for polysaccharides were time-consuming, laborious and energy-consuming. Microwave-assisted extraction (MAE) technique was employed for the extraction of Artemisia sphaerocephala polysaccharides (ASP), which is a traditional Chinese food. The extracting parameters were optimized by Box-Behnken design. In microwave heating process, a decrease in molecular weight (M(w)) was detected in SEC-LLS measurement. A d(f) value of 2.85 indicated ASP using MAE exhibited as a sphere conformation of branched clusters in aqueous solution. Furthermore, it showed stronger antioxidant activities compared with hot water extraction. The data obtained showed that the molecular weights played a more important role in antioxidant activities.

Pseudophasic extraction method for the separation of ultra-fine minerals

DOEpatents

Chaiko, David J.

2002-01-01

An improved aqueous-based extraction method for the separation and recovery of ultra-fine mineral particles. The process operates within the pseudophase region of the conventional aqueous biphasic extraction system where a low-molecular-weight, water soluble polymer alone is used in combination with a salt and operates within the pseudo-biphase regime of the conventional aqueous biphasic extraction system. A combination of low molecular weight, mutually immiscible polymers are used with or without a salt. This method is especially suited for the purification of clays that are useful as rheological control agents and for the preparation of nanocomposites.

High intensity ion beams from an atmospheric pressure inductively coupled plasma

NASA Astrophysics Data System (ADS)

Al Moussalami, S.; Chen, W.; Collings, B. A.; Douglas, D. J.

2002-02-01

This work is directed towards substantially improving the sensitivity of an inductively coupled plasma mass spectrometer (ICP-MS). Ions produced in the ICP at atmospheric pressure have been extracted with comparatively high current densities. The conventional approach to ion extraction, based on a skimmed molecular beam, has been abandoned, and a high extraction field arrangement has been adopted. Although the new approach is not optimized, current densities more than 180 times greater than that of a conventional interface have been extracted and analyte sensitivities ˜10-100× greater than those reported previously for quadrupole ICP-MS have been measured.

Surfactant-enhanced spectrofluorimetric determination of total aflatoxins from wheat samples after magnetic solid-phase extraction using modified Fe3O4 nanoparticles

NASA Astrophysics Data System (ADS)

Manafi, Mohammad Hanif; Allahyari, Mehdi; Pourghazi, Kamyar; Amoli-Diva, Mitra; Taherimaslak, Zohreh

2015-07-01

The extraction and preconcentration of total aflatoxins (including aflatoxin B1, B2, G1, and G2) using magnetic nanoparticles based solid phase extraction (MSPE) followed by surfactant-enhanced spectrofluorimetric detection was proposed. Ethylene glycol bis-mercaptoacetate modified silica coated Fe3O4 nanoparticles as an efficient antibody-free adsorbent was successfully applied to extract aflatoxins from wheat samples. High surface area and strong magnetization properties of magnetic nanoparticles were utilized to achieve high enrichment factor (97), and satisfactory recoveries (92-105%) using only 100 mg of the adsorbent. Furthermore, the fast separation time (less than 10 min) avoids many time-consuming cartridge loading or column-passing procedures accompany with the conventional SPE. In determination step, signal enhancement was performed by formation of Triton X-100 micelles around the analytes in 15% (v/v) acetonitrile-water which dramatically increase the sensitivity of the method. Main factors affecting the extraction efficiency and signal enhancement of the analytes including pH of sample solution, desorption conditions, extraction time, sample volume, adsorbent amount, surfactant concentration and volume and time of micelle formation were evaluated and optimized. Under the optimum conditions, wide linear range of 0.1-50 ng mL-1 with low detection limit of 0.03 ng mL-1 were obtained. The developed method was successfully applied to the extraction and preconcentration of aflatoxins in three commercially available wheat samples and the results were compared with the official AOAC method.

Optimization of ultrasound-assisted extraction to obtain mycosterols from Agaricus bisporus L. by response surface methodology and comparison with conventional Soxhlet extraction.

PubMed

Heleno, Sandrina A; Diz, Patrícia; Prieto, M A; Barros, Lillian; Rodrigues, Alírio; Barreiro, Maria Filomena; Ferreira, Isabel C F R

2016-04-15

Ergosterol, a molecule with high commercial value, is the most abundant mycosterol in Agaricus bisporus L. To replace common conventional extraction techniques (e.g. Soxhlet), the present study reports the optimal ultrasound-assisted extraction conditions for ergosterol. After preliminary tests, the results showed that solvents, time and ultrasound power altered the extraction efficiency. Using response surface methodology, models were developed to investigate the favourable experimental conditions that maximize the extraction efficiency. All statistical criteria demonstrated the validity of the proposed models. Overall, ultrasound-assisted extraction with ethanol at 375 W during 15 min proved to be as efficient as the Soxhlet extraction, yielding 671.5 ± 0.5mg ergosterol/100 g dw. However, with n-hexane extracts with higher purity (mg ergosterol/g extract) were obtained. Finally, it was proposed for the removal of the saponification step, which simplifies the extraction process and makes it more feasible for its industrial transference. Copyright © 2015 Elsevier Ltd. All rights reserved.

Procedures and Frequencies of Embalming and Heart Extractions in Modern Period in Brittany. Contribution to the Evolution of Ritual Funerary in Europe

PubMed Central

Dedouit, Fabrice; Duchesne, Sylvie; Mokrane, Fatima-Zohra; Gendrot, Véronique; Gérard, Patrice; Dabernat, Henri; Crubézy, Éric; Telmon, Norbert

2016-01-01

The evolution of funeral practices from the Middle Ages through the Modern era in Europe is generally seen as a process of secularization. The study, through imaging and autopsy, of two mummies, five lead urns containing hearts, and more than six hundred skeletons of nobles and clergymen from a Renaissance convent in Brittany has led us to reject this view. In addition to exceptional embalming, we observed instances in which hearts alone had been extracted, a phenomenon that had never before been described, and brains alone as well, and instances in which each spouse's heart had been placed on the other's coffin. In some identified cases we were able to establish links between the religious attitudes of given individuals and either ancient Medieval practices or more modern ones generated by the Council of Trent. All of these practices, which were a function of social status, were rooted in religion. They offer no evidence of secularization whatsoever. PMID:28030554

PCR Assays for Identification of Coccidioides posadasii Based on the Nucleotide Sequence of the Antigen 2/Proline-Rich Antigen

PubMed Central

Bialek, Ralf; Kern, Jan; Herrmann, Tanja; Tijerina, Rolando; Ceceñas, Luis; Reischl, Udo; González, Gloria M.

2004-01-01

A conventional nested PCR and a real-time LightCycler PCR assay for detection of Coccidioides posadasii DNA were designed and tested in 120 clinical strains. These had been isolated from 114 patients within 10 years in Monterrey, Nuevo Leon, Mexico, known to be endemic for coccidioidomycosis. The gene encoding the specific antigen 2/proline-rich antigen (Ag2/PRA) was used as a target. All strains were correctly identified, whereas DNA from related members of the family Onygenaceae remained negative. Melting curve analysis by LightCycler and sequencing of the 526-bp product of the first PCR demonstrated either 100% identity to the GenBank sequence of the Silveira strain, now known to be C. posadasii (accession number AF013256), or a single silent mutation at position 1228. Length determination of two microsatellite-containing loci (GAC and 621) identified all 120 isolates as C. posadasii. Specific DNA was amplified by conventional nested PCR from three microscopically spherule-positive paraffin-embedded tissue samples, whereas 20 human tissue samples positive for other dimorphic fungi remained negative. Additionally, the safety of each step of a modified commercially available DNA extraction procedure was evaluated by using 10 strains. At least three steps of the protocol were demonstrated to sufficiently kill arthroconidia. This safe procedure is applicable to cultures and to clinical specimens. PMID:14766853

Decellularized Human Dental Pulp as a Scaffold for Regenerative Endodontics.

PubMed

Song, J S; Takimoto, K; Jeon, M; Vadakekalam, J; Ruparel, N B; Diogenes, A

2017-06-01

Teeth undergo postnatal organogenesis relatively late in life and only complete full maturation a few years after the crown first erupts in the oral cavity. At this stage, development can be arrested if the tooth organ is damaged by either trauma or caries. Regenerative endodontic procedures (REPs) are a treatment alternative to conventional root canal treatment for immature teeth. These procedures rely on the transfer of apically positioned stem cells, including stem cells of the apical papilla (SCAP), into the root canal system. Although clinical success has been reported for these procedures, the predictability of expected outcomes and the organization of the newly formed tissues are affected by the lack of an available suitable scaffold that mimics the complexity of the dental pulp extracellular matrix (ECM). In this study, we evaluated 3 methods of decellularization of human dental pulp to be used as a potential autograft scaffold. Tooth slices of human healthy extracted third molars were decellularized by 3 different methods. One of the methods generated the maximum observed decellularization with minimal impact on the ECM composition and organization. Furthermore, recellularization of the scaffold supported the proliferation of SCAP throughout the scaffold with differentiation into odontoblast-like cells near the dentinal walls. Thus, this study reports that human dental pulp from healthy extracted teeth can be successfully decellularized, and the resulting scaffold supports the proliferation and differentiation of SCAP. The future application of this form of an autograft in REPs can fulfill a yet unmet need for a suitable scaffold, potentially improving clinical outcomes and ultimately promoting the survival and function of teeth with otherwise poor prognosis.

Comparison of extraction induced by emulsion breaking, ultrasonic extraction and wet digestion procedures for determination of metals in edible oil samples in Turkey using ICP-OES.

PubMed

Bakircioglu, Dilek; Kurtulus, Yasemin Bakircioglu; Yurtsever, Selcuk

2013-06-01

The content of elements (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in edible oils (sunflower, hazelnut, canola, corn and olive oils) from Turkey was determined using inductively coupled plasma optical emission spectrometry (ICP-OES) after ultrasonic extraction, wet digestion, and extraction induced by emulsion breaking procedures (EIEB). In order to evaluate the best sample preparation procedure, EIEB procedure was compared by ultrasonic extraction and wet digestion procedures. The results in the samples (minimum-maximum in mgkg(-1)) were : 0.022-0.058, Cr 0.126-7.106, Cu 0.570-4.504, Fe 8.004-12.588, Mn 0.035-0.054, Ni 0.908-2.182, Pb 0.099-0.134 and Zn 2.206-8.982. The EIEB procedure was found to be fast, reliable, simple, and excellent in comparison with the other studied procedures. The recovery test was performed by spiking the samples with known amounts of the metals in the form of organometallic standards and applying the EIEB procedure. The recoveries were in the range of 96-109%. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rapid and automated analysis of aflatoxin M1 in milk and dairy products by online solid phase extraction coupled to ultra-high-pressure-liquid-chromatography tandem mass spectrometry.

PubMed

Campone, Luca; Piccinelli, Anna Lisa; Celano, Rita; Pagano, Imma; Russo, Mariateresa; Rastrelli, Luca

2016-01-08

This study reports a fast and automated analytical procedure for the analysis of aflatoxin M1 (AFM1) in milk and dairy products. The method is based on the simultaneous protein precipitation and AFM1 extraction, by salt-induced liquid-liquid extraction (SI-LLE), followed by an online solid-phase extraction (online SPE) coupled to ultra-high-pressure-liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis to the automatic pre-concentration, clean up and sensitive and selective determination of AFM1. The main parameters affecting the extraction efficiency and accuracy of the analytical method were studied in detail. In the optimal conditions, acetonitrile and NaCl were used as extraction/denaturant solvent and salting-out agent in SI-LLE, respectively. After centrifugation, the organic phase (acetonitrile) was diluted with water (1:9 v/v) and purified (1mL) by online C18 cartridge coupled with an UHPLC column. Finally, selected reaction monitoring (SRM) acquisition mode was applied to the detection of AFM1. Validation studies were carried out on different dairy products (whole and skimmed cow milk, yogurt, goat milk, and powder infant formula), providing method quantification limits about 25 times lower than AFM1 maximum levels permitted by EU regulation 1881/2006 in milk and dairy products for direct human consumption. Recoveries (86-102%) and repeatability (RSD<3, n=6) meet the performance criteria required by EU regulation N. 401/2006 for the determination of the levels of mycotoxins in foodstuffs. Moreover, no matrix effects were observed in the different milk and dairy products studied. The proposed method improves the performance of AFM1 analysis in milk samples as AFM1 determination is performed with a degree of accuracy higher than the conventional methods. Other advantages are the reduction of sample preparation procedure, time and cost of the analysis, enabling high sample throughput that meet the current concerns of food safety and the public health protection. Copyright © 2015 Elsevier B.V. All rights reserved.

Kinetic improvement of olive leaves' bioactive compounds extraction by using power ultrasound in a wide temperature range.

PubMed

Khemakhem, Ibtihel; Ahmad-Qasem, Margarita Hussam; Catalán, Enrique Barrajón; Micol, Vicente; García-Pérez, Jose Vicente; Ayadi, Mohamed Ali; Bouaziz, Mohamed

2017-01-01

In this study, the effect of temperature and ultrasonic application on extraction kinetics of polyphenols from dried olive leaf was investigated. Conventional (CVE) and ultrasonic-assisted extraction (UAE) were performed at 10, 20, 30, 50 and 70°C using water as solvent. Extracts were characterized by measuring the total phenolic content, the antioxidant capacity and the oleuropein content (HPLC-DAD/MS-MS). Moreover, Naik's model was used to mathematically describe the extraction kinetics. The experimental results showed that phenolic extraction was faster in UAE (ultrasonic-assisted extraction) than in CVE (conventional extraction), being extraction kinetics satisfactorily described using Naik model (include VAR>98%). Besides, the total phenolic content, the antioxidant capacity and the oleuropein content were significantly (p<0.05) improved by increasing the temperature in both CVE and UAE. Oleuropein content reached 6.57±0.18 being extracted approximately 88% in the first minute for UAE experiments. Copyright © 2016 Elsevier B.V. All rights reserved.

Intensive diabetes therapy and ocular surgery in type 1 diabetes.

PubMed

Aiello, Lloyd Paul; Sun, Wanjie; Das, Arup; Gangaputra, Sapna; Kiss, Szilard; Klein, Ronald; Cleary, Patricia A; Lachin, John M; Nathan, David M

2015-04-30

The Diabetes Control and Complications Trial (DCCT) showed a beneficial effect of 6.5 years of intensive glycemic control on retinopathy in patients with type 1 diabetes. Between 1983 and 1989, a total of 1441 patients with type 1 diabetes in the DCCT were randomly assigned to receive either intensive diabetes therapy or conventional therapy aimed at preventing hyperglycemic symptoms. They were treated and followed until 1993. Subsequently, 1375 of these patients were followed in the observational Epidemiology of Diabetes Interventions and Complications (EDIC) study. The self-reported history of ocular surgical procedures was obtained annually. We evaluated the effect of intensive therapy as compared with conventional therapy on the incidence and cost of ocular surgery during these two studies. Over a median follow-up of 23 years, 130 ocular operations were performed in 63 of 711 patients assigned to intensive therapy (8.9%) and 189 ocular operations in 98 of 730 patients assigned to conventional therapy (13.4%) (P<0.001). After adjustment for DCCT baseline factors, intensive therapy was associated with a reduction in the risk of any diabetes-related ocular surgery by 48% (95% confidence interval [CI], 29 to 63; P<0.001) and a reduction in the risk of all such ocular procedures by 37% (95% CI, 12 to 55; P=0.01). Forty-two patients who received intensive therapy and 61 who received conventional therapy underwent cataract extraction (adjusted risk reduction with intensive therapy, 48%; 95% CI, 23 to 65; P=0.002); 29 patients who received intensive therapy and 50 who received conventional therapy underwent vitrectomy, retinal-detachment surgery, or both (adjusted risk reduction, 45%; 95% CI, 12 to 66; P=0.01). The costs of surgery were 32% lower in the intensive-therapy group. The beneficial effects of intensive therapy were fully attenuated after adjustment for mean glycated hemoglobin levels over the entire follow-up. Intensive therapy in patients with type 1 diabetes was associated with a substantial reduction in the long-term risk of ocular surgery. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; DCCT/EDIC ClinicalTrials.gov numbers, NCT00360893 and NCT00360815.).

Primary total hip replacement versus hip resurfacing - hospital considerations.

PubMed

Ward, William G; Carter, Christina J; Barone, Marisa; Jinnah, Riyaz

2011-01-01

Multiple factors regarding surgical procedures and patient selection affect hospital staffing needs as well as hospital revenues. In order to better understand the potential impact on hospitals that hip arthroplasty device selection (standard total hip arthroplasty vs. resurfacing) creates, a review of all primary hip arthroplasties performed at one institution was designed to identify factors that impacted hospital staffing needs and revenue generation. All primary hip arthroplasties undertaken over three fiscal years (2008 to 2010) were reviewed, utilizing only hospital business office data and medical records data that had been previously extracted prior for billing purposes. Analysis confirmed differing demographics for two hip arthroplasty populations, with the resurfacing patients (compared to the conventional total hip arthroplasty population) consisting of younger patients (mean age, 50 vs. 61 years), who were more often male (75% vs. 45%), were more likely to have osteoarthritis as their primary diagnosis (83 vs. 67%) and were more often covered by managed care or commercial insurance (83 vs. 34%). They also had shorter hospital stays (mean length of stay, 2.3 vs. 4.1 days) and consequently provided a more favorable financial revenue stream to the hospital on a per patient basis. Several trends appeared during the study periods. There was a steady increase in all procedures in all groups except for the resurfacings, which decreased 26% in males and 53% in females between 2009 and 2010. Differences were observed in the demographics of patients presenting for resurfacing, compared to those presenting for conventional total hip arthroplasty. In addition to the revenue stream considerations, institutions undertaking a resurfacing program must commit the resources and planning in order to rehabilitate these patients more expeditiously than is usually required with conventional hip arthroplasty patients.

Global harmonization of quality assurance naming conventions in radiation therapy clinical trials.

PubMed

Melidis, Christos; Bosch, Walther R; Izewska, Joanna; Fidarova, Elena; Zubizarreta, Eduardo; Ulin, Kenneth; Ishikura, Satoshi; Followill, David; Galvin, James; Haworth, Annette; Besuijen, Deidre; Clark, Catharine H; Clark, Clark H; Miles, Elizabeth; Aird, Edwin; Weber, Damien C; Hurkmans, Coen W; Verellen, Dirk

2014-12-01

To review the various radiation therapy quality assurance (RTQA) procedures used by the Global Clinical Trials RTQA Harmonization Group (GHG) steering committee members and present the harmonized RTQA naming conventions by amalgamating procedures with similar objectives. A survey of the GHG steering committee members' RTQA procedures, their goals, and naming conventions was conducted. The RTQA procedures were classified as baseline, preaccrual, and prospective/retrospective data capture and analysis. After all the procedures were accumulated and described, extensive discussions took place to come to harmonized RTQA procedures and names. The RTQA procedures implemented within a trial by the GHG steering committee members vary in quantity, timing, name, and compliance criteria. The procedures of each member are based on perceived chances of noncompliance, so that the quality of radiation therapy planning and treatment does not negatively influence the trial measured outcomes. A comparison of these procedures demonstrated similarities among the goals of the various methods, but the naming given to each differed. After thorough discussions, the GHG steering committee members amalgamated the 27 RTQA procedures to 10 harmonized ones with corresponding names: facility questionnaire, beam output audit, benchmark case, dummy run, complex treatment dosimetry check, virtual phantom, individual case review, review of patients' treatment records, and protocol compliance and dosimetry site visit. Harmonized RTQA harmonized naming conventions, which can be used in all future clinical trials involving radiation therapy, have been established. Harmonized procedures will facilitate future intergroup trial collaboration and help to ensure comparable RTQA between international trials, which enables meta-analyses and reduces RTQA workload for intergroup studies. Copyright © 2014 Elsevier Inc. All rights reserved.

a New Multi-Spectral Threshold Normalized Difference Water Index Mst-Ndwi Water Extraction Method - a Case Study in Yanhe Watershed

NASA Astrophysics Data System (ADS)

Zhou, Y.; Zhao, H.; Hao, H.; Wang, C.

2018-05-01

Accurate remote sensing water extraction is one of the primary tasks of watershed ecological environment study. Since the Yanhe water system has typical characteristics of a small water volume and narrow river channel, which leads to the difficulty for conventional water extraction methods such as Normalized Difference Water Index (NDWI). A new Multi-Spectral Threshold segmentation of the NDWI (MST-NDWI) water extraction method is proposed to achieve the accurate water extraction in Yanhe watershed. In the MST-NDWI method, the spectral characteristics of water bodies and typical backgrounds on the Landsat/TM images have been evaluated in Yanhe watershed. The multi-spectral thresholds (TM1, TM4, TM5) based on maximum-likelihood have been utilized before NDWI water extraction to realize segmentation for a division of built-up lands and small linear rivers. With the proposed method, a water map is extracted from the Landsat/TM images in 2010 in China. An accuracy assessment is conducted to compare the proposed method with the conventional water indexes such as NDWI, Modified NDWI (MNDWI), Enhanced Water Index (EWI), and Automated Water Extraction Index (AWEI). The result shows that the MST-NDWI method generates better water extraction accuracy in Yanhe watershed and can effectively diminish the confusing background objects compared to the conventional water indexes. The MST-NDWI method integrates NDWI and Multi-Spectral Threshold segmentation algorithms, with richer valuable information and remarkable results in accurate water extraction in Yanhe watershed.

Dental Procedures and the Risk of Infective Endocarditis

PubMed Central

Chen, Pei-Chun; Tung, Ying-Chang; Wu, Patricia W.; Wu, Lung-Sheng; Lin, Yu-Sheng; Chang, Chee-Jen; Kung, Suefang; Chu, Pao-Hsien

2015-01-01

Abstract Infective endocarditis (IE) is an uncommon but potentially devastating disease. Recently published data have revealed a significant increase in the incidence of IE following the restriction on indications for antibiotic prophylaxis as recommended by the revised guidelines. This study aims to reexamine the basic assumption behind the rationale of prophylaxis that dental procedures increase the risk of IE. Using the Longitudinal Health Insurance Database of Taiwan, we retrospectively analyzed a total of 739 patients hospitalized for IE between 1999 and 2012. A case-crossover design was conducted to compare the odds of exposure to dental procedures within 3 months preceding hospitalization with that during matched control periods when no IE developed. In the unadjusted model, the odds ratio (OR) was 0.93 for tooth extraction (95% confidence interval [CI] 0.54–1.59), 1.64 for surgery (95% CI 0.61–4.42), 0.92 for dental scaling (95% CI 0.59–1.42), 1.69 for periodontal treatment (95% CI 0.88–3.21), and 1.29 for endodontic treatment (95% CI 0.72–2.31). The association between dental procedures and the risk of IE remained insignificant after adjustment for antibiotic use, indicating that dental procedures did not increase the risk of IE. Therefore, this result may argue against the conventional assumption on which the recommended prophylaxis for IE is based. PMID:26512586

Chip-based nanoflow high performance liquid chromatography coupled to mass spectrometry for profiling of soybean flavonoids.

PubMed

Chang, Yuwei; Zhao, Chunxia; Wu, Zeming; Zhou, Jia; Zhao, Sumin; Lu, Xin; Xu, Guowang

2012-08-01

In this work a chip-based nano HPLC coupled MS (HPLC-chip/MS) method with a simple sample preparation procedure was developed for the flavonoid profiling of soybean. The analytical properties of the method including the linearity (R(2) , 0.992-0.995), reproducibility (RSD, 1.50-7.66%), intraday precision (RSD, 1.41-5.14%) and interday precision (RSD, 2.76-16.90%) were satisfactory. Compared with the conventional HPLC/MS method, a fast extraction and analysis procedure was applied and more flavonoids were detected in a single run. Additionally, 13 flavonoids in soybean seed were identified for the first time. The method was then applied to the profiling of six varieties of soybean sowed at the same place. A clear discrimination was observed among different cultivars, three isoflavones, accounting for nearly 80% of total flavonoid contents, were found increased in the spring soybeans compared with the summer cultivars. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Identification and quantitative determination of diphenylarsenic compounds in abandoned toxic smoke canisters.

PubMed

Hanaoka, Shigeyuki; Nomura, Koji; Kudo, Shinichi

2005-09-02

Knowledge of the exact nature of the constituents of abandoned chemical weapons (ACW) is a prerequisite for their orderly destruction. Here we report the development of analytical procedures to identify diphenylchloroarsine (DA/Clark I), diphenylcyanoarsine (DC/Clark II) and related substances employed in one of the munitions known as "Red canister". Both DA and DC are relatively unstable under conventional analytical procedures without thiol derivatization. Unfortunately however, thiol drivatization affords the same volatile organo-arsenic derivative from several different diphenylarsenic compounds, making it impossible to identify and quantify the original compounds. Further, diminishing the analytical interference caused by the celluloid powder used as a stacking material in the weapons, is also essential for accurate analysis. In this study, extraction and instrumental conditions have been evaluated and an optimal protocol was determined. The analysis of Red canister samples following this protocol showed that most of the DA and DC associated with pumice had degraded to bis(diphenylarsine)oxide (BDPAO), while those associated with celluloid were dominantly degraded to diphenylarsinic acid (DPAA).

Application of inductively coupled plasma sector field mass spectrometry for low-level environmental americium-241 analysis.

PubMed

Varga, Zsolt

2007-03-28

An improved and novel sample preparation method for (241)Am analysis by inductively coupled plasma sector field mass spectrometry has been developed. The procedure involves a selective CaF(2) pre-concentration followed by an extraction chromatographic separation using TRU resin. The achieved absolute detection limit of 0.86 fg (0.11 mBq) is comparable to that of alpha spectrometry (0.1 mBq) and suitable for low-level environmental measurements. Analysis of different kinds of environmental standard reference materials (IAEA-384--Fangataufa lagoon sediment, IAEA-385--Irish Sea sediment and IAEA-308--Mixed seaweed from the Mediterranean Sea) and alpha spectrometry were used to validate the procedure. The chemical recovery of sample preparation ranged between 72 and 94%. The results obtained are in good agreement with reference values and those measured by alpha spectrometry. The proposed method offers a rapid and less labor-intensive possibility for environmental (241)Am analysis than the conventionally applied radioanalytical techniques.

Radiosurgical fistulotomy; an alternative to conventional procedure in fistula in ano.

PubMed

Gupta, Pravin J

2003-01-01

Most surgeons continue to prefer the classic lay open technique [fistulotomy] as the gold standard of treatment in anal fistula. In this randomized study, a comparison is made between conventional fistulotomy and fistulotomy performed by a radio frequency device. One hundred patients of low anal fistula posted for fistulotomy were randomized prospectively to either a conventional or radio frequency technique. Parameters measured included time taken for the procedure, amount of blood loss, postoperative pain, return to work, and recurrence rate. The patient demographic was comparable in 2 groups. The radio frequency fistulotomy was quicker as compared to a conventional one [22 versus 37 minutes, p = 0.001], amount of bleeding was significantly less [47 ml versus 134 ml, p = 0.002], and hospital stay was less when patient was operated by radio frequency method [37 hours versus 56 hours in conventional method, p = 0.001]. The postoperative pain in the first 24 hours was more in conventional group [2 to 5 versus 0 to 3 on visual analogue scale]. The patients from radio frequency group resumed their duties early with a reduced healing period of the wounds [47 versus 64 days, p = 0.01]. The recurrence or failure rates were comparable in the radio frequency and conventional groups [2% versus 6%]. Fistulotomy procedure using a radio frequency technique has significant advantages over a conventional procedure with regard to operation time, blood loss, return to normal activity, and healing time of the wound.

Extraction of organic contaminants from marine sediments and tissues using microwave energy.

PubMed

Jayaraman, S; Pruell, R J; McKinney, R

2001-07-01

In this study, we compared microwave solvent extraction (MSE) to conventional methods for extracting organic contaminants from marine sediments and tissues with high and varying moisture content. The organic contaminants measured were polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, and polycyclic aromatic hydrocarbons (PAHs). Initial experiments were conducted on dry standard reference materials (SRMs) and field collected marine sediments. Moisture content in samples greatly influenced the recovery of the analytes of interest. When wet sediments were included in a sample batch, low recoveries were often encountered in other samples in the batch, including the dry SRM. Experiments were conducted to test the effect of standardizing the moisture content in all samples in a batch prior to extraction. SRM1941a (marine sediment). SRM1974a (mussel tissue), as well as QA96SED6 (marine sediment), and QA96TIS7 (marine tissue), both from 1996 NIST Intercalibration Exercise were extracted using microwave and conventional methods. Moisture levels were adjusted in SRMs to match those of marine sediment and tissue samples before microwave extraction. The results demonstrated that it is crucial to standardize the moisture content in all samples, including dry reference material to ensure good recovery of organic contaminants. MSE yielded equivalent or superior recoveries compared to conventional methods for the majority of the compounds evaluated. The advantages of MSE over conventional methods are reduced solvent usage, higher sample throughput and the elimination of halogenated solvent usage.

Effect of ultrasonic treatment on the polyphenol content and antioxidant capacity of extract from defatted hemp, flax and canola seed cakes.

PubMed

Teh, Sue-Siang; Birch, Edward John

2014-01-01

The effectiveness of ultrasonic extraction of phenolics and flavonoids from defatted hemp, flax and canola seed cakes was compared to the conventional extraction method. Ultrasonic treatment at room temperature showed increased polyphenol extraction yield and antioxidant capacity by two-fold over the conventional extraction method. Different combinations of ultrasonic treatment parameters consisting of solvent volume (25, 50, 75 and 100 mL), extraction time (20, 30 and 40 min) and temperature (40, 50, 60 and 70 °C) were selected for polyphenol extractions from the seed cakes. The chosen parameters had a significant effect (p<0.05) on the polyphenol extraction yield and subsequent antioxidant capacity from the seed cakes. Application of heat during ultrasonic extraction yielded higher polyphenol content in extracts compared to the non-heated extraction. From an orthogonal design test, the best combination of parameters was 50 mL of solvent volume, 20 min of extraction time and 70 °C of ultrasonic temperature. Copyright © 2013. Published by Elsevier B.V.

Red Fruits: Extraction of Antioxidants, Phenolic Content, and Radical Scavenging Determination: A Review

PubMed Central

Hidalgo, Gádor-Indra; Almajano, María Pilar

2017-01-01

Red fruits, as rich antioxidant foods, have gained over recent years capital importance for consumers and manufacturers. The industrial extraction of the phenolic molecules from this source has been taking place with the conventional solvent extraction method. New non-conventional extraction methods have been devised as environmentally friendly alternatives to the former method, such as ultrasound, microwave, and pressure assisted extractions. The aim of this review is to compile the results of recent studies using different extraction methodologies, identify the red fruits with higher antioxidant activity, and give a global overview of the research trends regarding this topic. As the amount of data available is overwhelming, only results referring to berries are included, leaving aside other plant parts such as roots, stems, or even buds and flowers. Several researchers have drawn attention to the efficacy of non-conventional extraction methods, accomplishing similar or even better results using these new techniques. Some pilot-scale trials have been performed, corroborating the applicability of green alternative methods to the industrial scale. Blueberries (Vaccinium corymbosum L.) and bilberries (Vaccinium myrtillus L.) emerge as the berries with the highest antioxidant content and capacity. However, several new up and coming berries are gaining attention due to global availability and elevated anthocyanin content. PMID:28106822

Study of Burn Scar Extraction Automatically Based on Level Set Method using Remote Sensing Data

PubMed Central

Liu, Yang; Dai, Qin; Liu, JianBo; Liu, ShiBin; Yang, Jin

2014-01-01

Burn scar extraction using remote sensing data is an efficient way to precisely evaluate burn area and measure vegetation recovery. Traditional burn scar extraction methodologies have no well effect on burn scar image with blurred and irregular edges. To address these issues, this paper proposes an automatic method to extract burn scar based on Level Set Method (LSM). This method utilizes the advantages of the different features in remote sensing images, as well as considers the practical needs of extracting the burn scar rapidly and automatically. This approach integrates Change Vector Analysis (CVA), Normalized Difference Vegetation Index (NDVI) and the Normalized Burn Ratio (NBR) to obtain difference image and modifies conventional Level Set Method Chan-Vese (C-V) model with a new initial curve which results from a binary image applying K-means method on fitting errors of two near-infrared band images. Landsat 5 TM and Landsat 8 OLI data sets are used to validate the proposed method. Comparison with conventional C-V model, OSTU algorithm, Fuzzy C-mean (FCM) algorithm are made to show that the proposed approach can extract the outline curve of fire burn scar effectively and exactly. The method has higher extraction accuracy and less algorithm complexity than that of the conventional C-V model. PMID:24503563

Direct identification of bacteria from BacT/ALERT anaerobic positive blood cultures by MALDI-TOF MS: MALDI Sepsityper kit versus an in-house saponin method for bacterial extraction.

PubMed

Meex, Cécile; Neuville, Florence; Descy, Julie; Huynen, Pascale; Hayette, Marie-Pierre; De Mol, Patrick; Melin, Pierrette

2012-11-01

In cases of bacteraemia, a rapid species identification of the causal agent directly from positive blood culture broths could assist clinicians in the timely targeting of empirical antimicrobial therapy. For this purpose, we evaluated the direct identification of micro-organisms from BacT/ALERT (bioMérieux) anaerobic positive blood cultures without charcoal using the Microflex matrix-assisted laser desorption/ionization (MALDI) time of flight MS (Bruker), after bacterial extraction by using two different methods: the MALDI Sepsityper kit (Bruker) and an in-house saponin lysis method. Bruker's recommended criteria for identification were expanded in this study, with acceptance of the species identification when the first three results with the best matches with the MALDI Biotyper database were identical, whatever the scores were. In total, 107 monobacterial cultures and six polymicrobial cultures from 77 different patients were included in this study. Among monomicrobial cultures, we identified up to the species level 67 and 66 % of bacteria with the MALDI Sepsityper kit and the saponin method, respectively. There was no significant difference between the two extraction methods. The direct species identification was particularly inconclusive for Gram-positive bacteria, as only 58 and 52 % of them were identified to the species level with the MALDI Sepsityper kit and the saponin method, respectively. Results for Gram-negative bacilli were better, with 82.5 and 90 % of correct identification to the species level with the MALDI Sepsityper kit and the saponin method, respectively. No misidentifications were given by the direct procedures when compared with identifications provided by the conventional method. Concerning the six polymicrobial blood cultures, whatever the extraction method used, a correct direct identification was only provided for one of the isolated bacteria on solid medium in all cases. The analysis of the time-to-result demonstrated a reduction in the turnaround time for identification ranging from 1 h 06 min to 24 h 44 min, when performing the blood culture direct identification in comparison with the conventional method, whatever the extraction method.

Ultrasound-assisted extraction of ginseng saponins from ginseng roots and cultured ginseng cells.

PubMed

Wu, J; Lin, L; Chau, F T

2001-10-01

Ultrasound-assisted extraction was evaluated as a simpler and more effective alternative to conventional extraction methods for the isolation of ginsenosides (saponins) from various types of ginseng. The ginseng samples were extracted with different solvents, under either direct sonication by an ultrasound probe horn or indirect sonication in an ultrasound cleaning bath. The ultrasonic extraction was compared with the conventional method of refluxing boiling solvents in a soxhlet extractor, on the yields of both the total saponin isolated by thin-layer chromatography and the individual ginsenosides by high performance liquid chromatography. It was found that the sonication-assisted extraction of ginseng saponins was about three times faster than the traditional extraction method. The ultrasonic extraction was not only more efficient but also convenient for the recovery and purification of the active ingredients of plant materials. In addition, the sonication-assisted extraction can be carried out at lower temperatures which are favorable for the thermally unstable compounds.

Comparison of microwave-assisted and conventional extraction of mangiferin from mango (Mangifera indica L.) leaves.

PubMed

Zou, Tangbin; Wu, Hongfu; Li, Huawen; Jia, Qing; Song, Gang

2013-10-01

Mangiferin is the main bioactive component in mango leaves, which possesses anti-inflammatory, antioxidative, antidiabetic, immunomodulatory, and antitumor activities. In the present study, a microwave-assisted extraction method was developed for the extraction of mangiferin from mango leaves. Some parameters such as ethanol concentration, liquid-to-solid ratio, microwave power, and extraction time were optimized by single-factor experiments and response surface methodology. The optimal extraction conditions were 45% ethanol, liquid-to-solid ratio of 30:1 (mL/g), and extraction time of 123 s under microwave irradiation of 474 W. Under optimal conditions, the yield of mangiferin was 36.10 ± 0.72 mg/g, significantly higher than that of conventional extraction. The results obtained are beneficial for the full utilization of mango leaves and also indicate that microwave-assisted extraction is a very useful method for extracting mangiferin from plant materials. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improved collagen extraction from jellyfish (Acromitus hardenbergi) with increased physical-induced solubilization processes.

PubMed

Khong, Nicholas M H; Yusoff, Fatimah Md; Jamilah, B; Basri, Mahiran; Maznah, I; Chan, Kim Wei; Armania, Nurdin; Nishikawa, Jun

2018-06-15

Efficiency and effectiveness of collagen extraction process contribute to huge impacts to the quality, supply and cost of the collagen produced. Jellyfish is a potential sustainable source of collagen where their applications are not limited by religious constraints and threats of transmittable diseases. The present study compared the extraction yield, physico-chemical properties and toxicology in vitro of collagens obtained by the conventional acid-assisted and pepsin-assisted extraction to an improved physical-aided extraction process. By increasing physical intervention, the production yield increased significantly compared to the conventional extraction processes (p < .05). Collagen extracted using the improved process was found to possess similar proximate and amino acids composition to those extracted using pepsin (p > .05) while retaining high molecular weight distributions and polypeptide profiles similar to those extracted using only acid. Moreover, they exhibited better appearance, instrumental colour and were found to be non-toxic in vitro and free of heavy metal contamination. Copyright © 2017 Elsevier Ltd. All rights reserved.

New fixation method for maxillary distraction osteogenesis using locking attachments.

PubMed

Suzuki, Eduardo Yugo; Buranastidporn, Boonsiva; Ishii, Masatoshi

2006-10-01

The external traction hooks of the intraoral splint used in the rigid external distraction (RED) system for maxillary distraction osteogenesis interfere with the surgical procedures. The purpose of this study is to introduce an innovative splint fixation method for maxillary distraction osteogenesis with Locking Attachments and evaluate their advantages, such as reduction of operating time compared with the traditional intraoral splint method. Retrospective comparison of operative times of maxillary Le Fort I osteotomy procedures was carried out with the traditional protocol using the intraoral splint cemented to the maxillary dentition (n = 14), and a removable intraoral splint that is inserted postsurgically (n = 14). Operative procedure times were compared and analyzed statistically using the data extracted from the surgical records. There were no complications inserting the removable splint postsurgically, including pain, discomfort, or time-consuming procedure. Stable and secure splint fixation was obtained before the distraction procedure and the desired treatment goals were obtained in all patients. The total operative procedure times were significantly reduced in the Locking Attachments group by 24% to 41% (approximately 65 minutes) compared with earlier operations involving the conventional splints (P < .05). Maxillary distraction osteogenesis with the Locking Attachments is a highly effective fixation approach to manage severe hypoplastic maxilla, eliminating lip constraints resulting from scarring and allowing for easier, more deliberate and careful dissection. The use of the Locking Attachments is reliable in craniofacial surgery and has proved to be advantageous in the reduction of the operating time and surgical risks.

Precision of guided scanning procedures for full-arch digital impressions in vivo.

PubMed

Zimmermann, Moritz; Koller, Christina; Rumetsch, Moritz; Ender, Andreas; Mehl, Albert

2017-11-01

System-specific scanning strategies have been shown to influence the accuracy of full-arch digital impressions. Special guided scanning procedures have been implemented for specific intraoral scanning systems with special regard to the digital orthodontic workflow. The aim of this study was to evaluate the precision of guided scanning procedures compared to conventional impression techniques in vivo. Two intraoral scanning systems with implemented full-arch guided scanning procedures (Cerec Omnicam Ortho; Ormco Lythos) were included along with one conventional impression technique with irreversible hydrocolloid material (alginate). Full-arch impressions were taken three times each from 5 participants (n = 15). Impressions were then compared within the test groups using a point-to-surface distance method after best-fit model matching (OraCheck). Precision was calculated using the (90-10%)/2 quantile and statistical analysis with one-way repeated measures ANOVA and post hoc Bonferroni test was performed. The conventional impression technique with alginate showed the lowest precision for full-arch impressions with 162.2 ± 71.3 µm. Both guided scanning procedures performed statistically significantly better than the conventional impression technique (p < 0.05). Mean values for group Cerec Omnicam Ortho were 74.5 ± 39.2 µm and for group Ormco Lythos 91.4 ± 48.8 µm. The in vivo precision of guided scanning procedures exceeds conventional impression techniques with the irreversible hydrocolloid material alginate. Guided scanning procedures may be highly promising for clinical applications, especially for digital orthodontic workflows.

Multianalyte, high-throughput liquid chromatography tandem mass spectrometry method for the sensitive determination of fungicides and insecticides in wine.

PubMed

Castro, Gabriela; Pérez-Mayán, Leticia; Rodríguez-Cabo, Tamara; Rodríguez, Isaac; Ramil, Maria; Cela, Rafael

2018-01-01

Evidence of pesticide transfer from grapes to wine, added to differences in the national regulations regarding the number and the maximum concentration of these species in wine, demands analytical procedures suitable for their routine control in this foodstuff. In this research, solid-phase extraction (SPE) and ultra-performance liquid chromatography (UPLC), with tandem mass spectrometry (MS/MS) detection, are combined to obtain a sensitive and rapid procedure to determine 50 pesticides in red and white wines. Efficiency and selectivity of sample preparation are correlated with the type of sorbent, the elution solvent, and the physicochemical properties of pesticides. SPE of 2-mL wine samples followed by direct injection of the extract in the UPLC-MS/MS system provides quantification limits (LOQs) below 1 ng mL -1 for 48 out of 50 compounds, linear responses up to 200 ng mL -1 , and acceptable accuracy, employing quantification against solvent-based standards, for 45 species. A total analysis time of 10 min, including compounds separation and re-equilibration of the UPLC column, was achieved. The developed methodology was applied to 25 wines (20 conventional and 5 ecological), produced in 7 different countries. Out of 27 pesticides quantified in these wines, 12 displayed occurrence frequencies above 24%; moreover, all wines, except one of the ecological ones, contained residues from at least one pesticide.

Marginal and Internal Gap of Handmade, Milled and 3D Printed Additive Manufactured Patterns for Pressed Lithium Disilicate Onlay Restorations.

PubMed

Revilla-León, M; Olea-Vielba, M; Esteso-Saiz, A; Martínez-Klemm, I; Özcan, M

2018-03-01

On a pressed lithium disilicate restoration, the building up of a wax pattern of the future restoration is a necessary step on the fabrication process. Conventionally, a wax pattern can be produced by handmade or milled procedures; however, the development of additive manufacturing technologies allows a new fabrication method. The present study measured the marginal and internal gap of handmade, milled and additive manufactured patterns for an onlay restoration. A preparation of an onlay restoration was made on an extracted mandibular tooth. A definitive cast was fabricated from a conventional silicone impression of the prepared tooth. Three groups were established: handmade (HM), milled (ML) and additive manufactured (AM); 4 specimens per group were obtained. The marginal and internal gap of each pattern was measured on the extracted molar through a computed tomography test. Sixty measurements were done to measure the marginal gap and another 60 measurements were calculated to analyze the internal gap on each pattern on the prepared tooth. A total of 1.440 measurements were completed. Mann-Whitney and Turkey statistical tests were used for pairwise comparison. The mean of the marginal and internal gap was of 67.56 ± 6.08 μm and 80.62 ± 3.26 μm for the HM group, 85.28 ± 2.17 μm and 96 ± 1.97 μm for the ML group and 86.49 ± 1.74 μm and 91.86 ± 2.88 μm for the AM group, respectively. The HM group presented significantly lower marginal (p=0.029) and internal (p=0.029) gap compared to the ML and AM groups. There was no statistical significant difference (p=0.486) on the marginal gap between the ML and the AM groups, but the AM group, showed significantly (p=0.029) smaller internal gap than the ML group. All the groups presented less than 100 μm marginal and internal gap, which is a considered clinically acceptable. The three fabrication processes are viable option for manufacturing patterns for lithium disilicate onlay restorations, but the best marginal and internal fit was still obtained by the conventional handmade procedures. Copyright© 2018 Dennis Barber Ltd.

Analysis of free and bound chlorophenoxy acids in cereals.

PubMed

Lokke, H

1975-06-01

Extraction of the chlorophenoxy acids 2,4-D and dichlorprop in cereals has been examined by analyzing barley from spraying experiments. A procedure has been set up by combination of acid hydrolysis and enzymatic degradation followed by extraction and clean up on either silica gel or basic aluminum oxide. The final determination is based on reaction with diazomethane and subsequently GLC with ECD. This procedure was compared with two different extraction procedures previously described in the literature. The one comparative procedure uses a mixture of 50% diethyl ether/hexane in presence of sulphuric acid and resulted in residues up to ten times lower than found after the combined acid hydrolysis/enzymatic degradation procedure. In the second comparison a direct extraction was made with a mixture of 65% (v/v) acetonitrile in water. No differences were found between this and the combined acid hydrolysis/enzymatic degradation procedure.

Rapid and green analytical method for the determination of quinoline alkaloids from Cinchona succirubra based on Microwave-Integrated Extraction and Leaching (MIEL) prior to high performance liquid chromatography.

PubMed

Fabiano-Tixier, Anne-Sylvie; Elomri, Abdelhakim; Blanckaert, Axelle; Seguin, Elisabeth; Petitcolas, Emmanuel; Chemat, Farid

2011-01-01

Quinas contains several compounds, such as quinoline alkaloids, principally quinine, quinidine, cinchonine and cichonidine. Identified from barks of Cinchona, quinine is still commonly used to treat human malaria. Microwave-Integrated Extraction and Leaching (MIEL) is proposed for the extraction of quinoline alkaloids from bark of Cinchona succirubra. The process is performed in four steps, which ensures complete, rapid and accurate extraction of the samples. Optimal conditions for extraction were obtained using a response surface methodology reached from a central composite design. The MIEL extraction has been compared with a conventional technique soxhlet extraction. The extracts of quinoline alkaloids from C. succirubra obtained by these two different methods were compared by HPLC. The extracts obtained by MIEL in 32 min were quantitatively (yield) and qualitatively (quinine, quinidine, cinchonine, cinchonidine) similar to those obtained by conventional Soxhlet extraction in 3 hours. MIEL is a green technology that serves as a good alternative for the extraction of Cinchona alkaloids.

Rapid and Green Analytical Method for the Determination of Quinoline Alkaloids from Cinchona succirubra Based on Microwave-Integrated Extraction and Leaching (MIEL) Prior to High Performance Liquid Chromatography

PubMed Central

Fabiano-Tixier, Anne-Sylvie; Elomri, Abdelhakim; Blanckaert, Axelle; Seguin, Elisabeth; Petitcolas, Emmanuel; Chemat, Farid

2011-01-01

Quinas contains several compounds, such as quinoline alkaloids, principally quinine, quinidine, cinchonine and cichonidine. Identified from barks of Cinchona, quinine is still commonly used to treat human malaria. Microwave-Integrated Extraction and Leaching (MIEL) is proposed for the extraction of quinoline alkaloids from bark of Cinchona succirubra. The process is performed in four steps, which ensures complete, rapid and accurate extraction of the samples. Optimal conditions for extraction were obtained using a response surface methodology reached from a central composite design. The MIEL extraction has been compared with a conventional technique soxhlet extraction. The extracts of quinoline alkaloids from C. succirubra obtained by these two different methods were compared by HPLC. The extracts obtained by MIEL in 32 min were quantitatively (yield) and qualitatively (quinine, quinidine, cinchonine, cinchonidine) similar to those obtained by conventional Soxhlet extraction in 3 hours. MIEL is a green technology that serves as a good alternative for the extraction of Cinchona alkaloids. PMID:22174637

Evaluation of the nitrate content in leaf vegetables produced through different agricultural systems.

PubMed

Guadagnin, S G; Rath, S; Reyes, F G R

2005-12-01

The nitrate content of leafy vegetables (watercress, lettuce and arugula) produced by different agricultural systems (conventional, organic and hydroponic) was determined. The daily nitrate intake from the consumption of these crop species by the average Brazilian consumer was also estimated. Sampling was carried out between June 2001 to February 2003 in Campinas, São Paulo State, Brazil. Nitrate was extracted from the samples using the procedure recommended by the AOAC. Flow injection analysis with spectrophotometric detection at 460 nm was used for nitrate determination through the ternary complex FeSCNNO+. For lettuce and arugula, the average nitrate content varied (p < 0.05) between the three agricultural systems with the nitrate level in the crops produced by the organic system being lower than in the conventional system that, in turn, was lower than in the hydroponic system. For watercress, no difference (p < 0.05) was found between the organic and hydroponic samples, both having higher nitrate contents (p < 0.05) than conventionally cultivated samples. The nitrate content for each crop species varied among producers, between different parts of the plant and in relation to the season. The estimated daily nitrate intake, calculated from the consumption of the crops produced by the hydroponic system, represented 29% of the acceptable daily intake established for this ion.

Performance testing of NIOSH Method 5524/ASTM Method D-7049-04, for determination of metalworking fluids.

PubMed

Glaser, Robert; Kurimo, Robert; Shulman, Stanley

2007-08-01

A performance test of NIOSH Method 5524/ASTM Method D-7049-04 for analysis of metalworking fluids (MWF) was conducted. These methods involve determination of the total and extractable weights of MWF samples; extractions are performed using a ternary blend of toluene:dichloromethane:methanol and a binary blend of methanol:water. Six laboratories participated in this study. A preliminary analysis of 20 blank samples was made to familiarize the laboratories with the procedure(s) and to estimate the methods' limits of detection/quantitation (LODs/LOQs). Synthetically generated samples of a semisynthetic MWF aerosol were then collected on tared polytetrafluoroethylene (PTFE) filters and analyzed according to the methods by all participants. Sample masses deposited (approximately 400-500 micro g) corresponded to amounts expected in an 8-hr shift at the NIOSH recommended exposure levels (REL) of 0.4 mg/m(3) (thoracic) and 0.5 mg/m(3) (total particulate). The generator output was monitored with a calibrated laser particle counter. One laboratory significantly underreported the sampled masses relative to the other five labs. A follow-up study compared only gravimetric results of this laboratory with those of two other labs. In the preliminary analysis of blanks; the average LOQs were 0.094 mg for the total weight analysis and 0.136 mg for the extracted weight analyses. For the six-lab study, the average LOQs were 0.064 mg for the total weight analyses and 0.067 mg for the extracted weight analyses. Using ASTM conventions, h and k statistics were computed to determine the degree of consistency of each laboratory with the others. One laboratory experienced problems with precision but not bias. The precision estimates for the remaining five labs were not different statistically (alpha = 0.005) for either the total or extractable weights. For all six labs, the average fraction extracted was > or =0.94 (CV = 0.025). Pooled estimates of the total coefficients of variation of analysis were 0.13 for the total weight samples and 0.13 for the extracted weight samples. An overall method bias of -5% was determined by comparing the overall mean concentration reported by the participants to that determined by the particle counter. In the three-lab follow-up study, the nonconsistent lab reported results that were unbiased but statistically less precise than the others; the average LOQ was 0.133 mg for the total weight analyses. It is concluded that aerosolized MWF sampled at concentrations corresponding to either of the NIOSH RELs can generally be shipped unrefrigerated, stored refrigerated up to 7 days, and then analyzed quantitatively and precisely for MWF using the NIOSH/ASTM procedures.

Extraction of DNA from forensic-type sexual assault specimens using simple, rapid sonication procedures.

PubMed

Crouse, C A; Ban, J D; D'Alessio, J K

1993-10-01

Sonication procedures for the extraction of DNA from forensic-type semen specimens have been developed, which, when compared to currently utilized sperm DNA extraction techniques, are simple, rapid and result in comparable DNA yields. Sperm DNA extraction by sonication was performed on whole semen, seminal stains, buccal swabs and post-coital specimens. Ultrasound disruption of sperm cells and their ultimate release of cellular DNA has been conducted in the presence of sperm wash buffers followed by organic extraction or Chelex 100 with little or no compromise to DNA quality, quantity or amplifiability. Two advantages of sonication over currently used forensic techniques to extract sperm DNA include 1) sperm DNA extraction that occurs within five minutes of sonication compared with an hour or greater for water bath incubations in classic enzyme digestion DNA extractions and 2) one less preparatory step with the Chelex/sonication protocol and three less steps with the sonication/organic protocol compared with other procedures thus eliminating potential sample-to-sample cross-contamination. Sperm DNA extracted by optimum sonication procedures was used for forensic HLA DQ alpha typing and restriction fragment length polymorphisms analysis without any adverse effects on typing results.

Utilization of non-conventional systems for conversion of biomass to food components

NASA Technical Reports Server (NTRS)

Karel, M.; Nakhost, Z.

1989-01-01

The potential use of micro-algae in yielding useful macronutrients for the CELSS is investigated. Algal proteins were isolated and characterized from green algae (Scenedesmus obliquus) grown under controlled conditions. The RNA and DNA contents were determined, and methodology for reduction of the nucleic acid content to acceptable levels developed. Lipid extraction procedures using supercritical fluids were tailored to removal of undesirable lipids and pigments. Initial steps toward preparation of model foods for potential use in the CELSS were taken. The goal was to fabricate food products which contain isolated algal macronutrients such as proteins and lipids and also some components derived from higher plants including wheat flour, soy flour, potato powder (flakes), soy oil, and corn syrup.

Global Harmonization of Quality Assurance Naming Conventions in Radiation Therapy Clinical Trials

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

Melidis, Christos, E-mail: christos.melidis@eortc.be; Bosch, Walther R.; Izewska, Joanna

2014-12-01

Purpose: To review the various radiation therapy quality assurance (RTQA) procedures used by the Global Clinical Trials RTQA Harmonization Group (GHG) steering committee members and present the harmonized RTQA naming conventions by amalgamating procedures with similar objectives. Methods and Materials: A survey of the GHG steering committee members' RTQA procedures, their goals, and naming conventions was conducted. The RTQA procedures were classified as baseline, preaccrual, and prospective/retrospective data capture and analysis. After all the procedures were accumulated and described, extensive discussions took place to come to harmonized RTQA procedures and names. Results: The RTQA procedures implemented within a trial by themore » GHG steering committee members vary in quantity, timing, name, and compliance criteria. The procedures of each member are based on perceived chances of noncompliance, so that the quality of radiation therapy planning and treatment does not negatively influence the trial measured outcomes. A comparison of these procedures demonstrated similarities among the goals of the various methods, but the naming given to each differed. After thorough discussions, the GHG steering committee members amalgamated the 27 RTQA procedures to 10 harmonized ones with corresponding names: facility questionnaire, beam output audit, benchmark case, dummy run, complex treatment dosimetry check, virtual phantom, individual case review, review of patients' treatment records, and protocol compliance and dosimetry site visit. Conclusions: Harmonized RTQA harmonized naming conventions, which can be used in all future clinical trials involving radiation therapy, have been established. Harmonized procedures will facilitate future intergroup trial collaboration and help to ensure comparable RTQA between international trials, which enables meta-analyses and reduces RTQA workload for intergroup studies.« less

Recent advances in analytical methods for the determination of 4-alkylphenols and bisphenol A in solid environmental matrices: A critical review.

PubMed

Salgueiro-González, N; Castiglioni, S; Zuccato, E; Turnes-Carou, I; López-Mahía, P; Muniategui-Lorenzo, S

2018-09-18

The problem of endocrine disrupting compounds (EDCs) in the environment has become a worldwide concern in recent decades. Besides their toxicological effects at low concentrations and their widespread use in industrial and household applications, these pollutants pose a risk for non-target organisms and also for public safety. Analytical methods to determine these compounds at trace levels in different matrices are urgently needed. This review critically discusses trends in analytical methods for well-known EDCs like alkylphenols and bisphenol A in solid environmental matrices, including sediment and aquatic biological samples (from 2006 to 2018). Information about extraction, clean-up and determination is covered in detail, including analytical quality parameters (QA/QC). Conventional and novel analytical techniques are compared, with their advantages and drawbacks. Ultrasound assisted extraction followed by solid phase extraction clean-up is the most widely used procedure for sediment and aquatic biological samples, although softer extraction conditions have been employed for the latter. The use of liquid chromatography followed by tandem mass spectrometry has greatly increased in the last five years. The majority of these methods have been employed for the analysis of river sediments and bivalve molluscs because of their usefulness in aquatic ecosystem (bio)monitoring programs. Green, simple, fast analytical methods are now needed to determine these compounds in complex matrices. Copyright © 2018 Elsevier B.V. All rights reserved.

Bioprocess considerations for expanded-bed chromatography of crude canola extract: sample preparation and adsorbent reuse.

PubMed

Bai, Yun; Glatz, Charles E

2003-03-30

Compared to the conventional microbial and mammalian systems, transgenic plants produce proteins in a different matrix. This provides opportunities and challenges for downstream processing. In the context of the plant host Brassica napus (canola), this work addresses the bioprocessing challenges of solid fractionation, resin fouling by native plant components (e.g., oil, phenolics, etc.), hydrodynamic stability, and resin reuse for expanded bed adsorption for product capture. Plant tissue processing and subsequent protein extraction typically result in an extract with a high content of solids containing a wide particle-size distribution. Without removal of larger particles, the column inlet distributor plugged. The larger particles (> 50 microm) were easily removed through centrifugal settling comparable to that attainable with a scroll decanter. The remaining solids did not affect the column performance. Less than 4% of the lipids and phenolics in the fed extract bound to STREAMLINE trade mark DEAE resin, and this small proportion could be satisfactorily removed using recommended clean-in-place (CIP) procedures. Hydrodynamic expansion and adsorption kinetics of the STREAMLINE trade mark DEAE resin were maintained throughout 10 cycles of reuse, as was the structural integrity of the resin beads. No significant accumulation of N-rich (e.g., proteins) and C/O-rich components (e.g., oil and phenolics) occurred over the same period. Copyright 2003 Wiley Periodicals Inc. Biotechnol Bioeng 81: 775-782, 2003.

Risks of postextraction bleeding after receiving direct oral anticoagulants or warfarin: a retrospective cohort study

PubMed Central

Yagyuu, Takahiro; Kawakami, Mao; Ueyama, Yoshihiro; Imada, Mitsuhiko; Kurihara, Miyako; Matsusue, Yumiko; Imai, Yuichiro; Yamamoto, Kazuhiko; Kirita, Tadaaki

2017-01-01

Objective The effect of direct oral anticoagulants (DOACs) on the risk of bleeding after tooth extraction remains unclear. This study aimed to evaluate the incidence of postextraction bleeding among patients who received DOAC and vitamin K antagonists (VKAs), such as warfarin. Design This study was a retrospective cohort analysis. Incidence rates and propensity score-matched regression models were used to compare the risks of bleeding after tooth extractions involving DOACs and VKAs. Setting The study took place in a single university hospital in Japan. Participants Between April 2013 and April 2015, 543 patients underwent a total of 1196 simple tooth extractions. Primary outcome measure The primary outcome measure was the occurrence of postextraction bleeding, which was defined as bleeding that could not be stopped by biting down on gauze and required medical treatment between 30 min and 7 days after the extraction. Results A total of 1196 tooth extractions (634 procedures) in 541 patients fulfilled the study criteria, with 72 extractions (41 procedures) involving DOACs, 100 extractions (50 procedures) involving VKAs and 1024 extractions (543 procedures) involving no anticoagulants. The incidences of postextraction bleeding per tooth for the DOAC, VKA and no anticoagulant extractions were 10.4%, 12.0% and 0.9%, respectively. The incidences of postextraction bleeding per procedure for DOACs, VKAs and no anticoagulants were 9.7%, 10.0% and 1.1%, respectively. In comparison to the VKA extractions, the DOAC extractions did not significantly increase the risk of postextraction bleeding (OR 0.69, 95% CIs 0.24 to 1.97; p=0.49). Conclusions The risk of postextraction bleeding was similar for DOAC and VKA extractions. PMID:28827248

New microwave-integrated Soxhlet extraction. An advantageous tool for the extraction of lipids from food products.

PubMed

Virot, Matthieu; Tomao, Valérie; Colnagui, Giulio; Visinoni, Franco; Chemat, Farid

2007-12-07

A new process of Soxhlet extraction assisted by microwave was designed and developed. The process is performed in four steps, which ensures complete, rapid and accurate extraction of the samples. A second-order central composite design (CCD) has been used to investigate the performance of the new device. The results provided by analysis of variance and Pareto chart, indicated that the extraction time was the most important factor followed by the leaching time. The response surface methodology allowed us to determine optimal conditions for olive oil extraction: 13 min of extraction time, 17 min of leaching time, and 720 W of irradiation power. The proposed process is suitable for lipids determination from food. Microwave-integrated Soxhlet (MIS) extraction has been compared with a conventional technique, Soxhlet extraction, for the extraction of oil from olives (Aglandau, Vaucluse, France). The oils extracted by MIS for 32 min were quantitatively (yield) and qualitatively (fatty acid composition) similar to those obtained by conventional Soxhlet extraction for 8 h. MIS is a green technology and appears as a good alternative for the extraction of fat and oils from food products.

Antioxidant potential of banana: Study using simulated gastrointestinal model and conventional extraction.

PubMed

Bhatt, Anjali; Patel, Vinayak

2015-07-01

Most reports on fruit antioxidant capacities are based on extraction of antioxidants using polar solvents. In banana, little is known about the fate of bioactive compounds during the digestion process, particularly in the food matrix under the gastric and intestinal conditions. In the present study, an in vitro gastrointestinal digestion method was used to simulate physiological conditions of the stomach and small intestine to evaluate the actual antioxidant capacity of banana. The simulated gastrointestinal extracts showed significantly higher antioxidant properties. The total phenol content of the physiological enzymatic extract was higher by almost 150% than the methanolic extract. Similarly, the flavonoid and flavonol contents were higher in the physiological enzymatic extract by 330.6 and 141.7%, respectively as compared to methanolic extract. These differences were also noticed in the antioxidant capacity measurement parameters. From the results, it can be concluded that the conventional extracts underrate the antioxidant value of banana and that they may have much higher health significance, as an antioxidant in particular.

Influence of Extraction Methods on the Yield of Steviol Glycosides and Antioxidants in Stevia rebaudiana Extracts.

PubMed

Periche, Angela; Castelló, Maria Luisa; Heredia, Ana; Escriche, Isabel

2015-06-01

This study evaluated the application of ultrasound techniques and microwave energy, compared to conventional extraction methods (high temperatures at atmospheric pressure), for the solid-liquid extraction of steviol glycosides (sweeteners) and antioxidants (total phenols, flavonoids and antioxidant capacity) from dehydrated Stevia leaves. Different temperatures (from 50 to 100 °C), times (from 1 to 40 min) and microwave powers (1.98 and 3.30 W/g extract) were used. There was a great difference in the resulting yields according to the treatments applied. Steviol glycosides and antioxidants were negatively correlated; therefore, there is no single treatment suitable for obtaining the highest yield in both groups of compounds simultaneously. The greatest yield of steviol glycosides was obtained with microwave energy (3.30 W/g extract, 2 min), whereas, the conventional method (90 °C, 1 min) was the most suitable for antioxidant extraction. Consequently, the best process depends on the subsequent use (sweetener or antioxidant) of the aqueous extract of Stevia leaves.

Role of modifier in microwave assisted extraction of oleanolic acid from Gymnema sylvestre: application of green extraction technology for botanicals.

PubMed

Mandal, Vivekananda; Dewanjee, Saikat; Mandal, Subhash C

2009-08-01

This work highlights the development of a green extraction technology for botanicals with the use of microwave energy. Taking into consideration the extensive time involved in conventional extraction methods, coupled with usage of large volumes of organic solvent and energy resources, an ecofriendly green method that can overcome the above problems has been developed. The work compares the effect of sample pretreatment with untreated sample for improved yield of oleanolic acid from Gymnema sylvestre leaves. The pretreated sample with water produced 0.71% w/w oleanolic acid in one extraction cycle with 500 W microwave power, 25 mL methanol and only an 8 min extraction time. On the other hand, a conventional heat reflux extraction for 6 hours could produce only 0.62% w/w oleanolic acid. The detailed mechanism of extraction has been studied through scanning electron micrographs. The environmental impact of the proposed green method has also been evaluated.

A comparison of essential oils obtained from lavandin via different extraction processes: Ultrasound, microwave, turbohydrodistillation, steam and hydrodistillation.

PubMed

Périno-Issartier, Sandrine; Ginies, Christian; Cravotto, Giancarlo; Chemat, Farid

2013-08-30

A total of eight extraction techniques ranging from conventional methods (hydrodistillation (HD), steam distillation (SD), turbohydrodistillation (THD)), through innovative techniques (ultrasound assisted extraction (US-SD) and finishing with microwave assisted extraction techniques such as In situ microwave-generated hydrodistillation (ISMH), microwave steam distillation (MSD), microwave hydrodiffusion and gravity (MHG), and microwave steam diffusion (MSDf)) were used to extract essential oil from lavandin flowers and their results were compared. Extraction time, yield, essential oil composition and sensorial analysis were considered as the principal terms of comparison. The essential oils extracted using the more innovative processes were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained from the conventional techniques. The method which gave the best results was the microwave hydrodiffusion and gravity (MHG) method which gave reduced extraction time (30min against 220min for SD) and gave no differences in essential oil yield and sensorial perception. Copyright © 2013 Elsevier B.V. All rights reserved.

Similarity estimation for reference image retrieval in mammograms using convolutional neural network

NASA Astrophysics Data System (ADS)

Muramatsu, Chisako; Higuchi, Shunichi; Morita, Takako; Oiwa, Mikinao; Fujita, Hiroshi

2018-02-01

Periodic breast cancer screening with mammography is considered effective in decreasing breast cancer mortality. For screening programs to be successful, an intelligent image analytic system may support radiologists' efficient image interpretation. In our previous studies, we have investigated image retrieval schemes for diagnostic references of breast lesions on mammograms and ultrasound images. Using a machine learning method, reliable similarity measures that agree with radiologists' similarity were determined and relevant images could be retrieved. However, our previous method includes a feature extraction step, in which hand crafted features were determined based on manual outlines of the masses. Obtaining the manual outlines of masses is not practical in clinical practice and such data would be operator-dependent. In this study, we investigated a similarity estimation scheme using a convolutional neural network (CNN) to skip such procedure and to determine data-driven similarity scores. By using CNN as feature extractor, in which extracted features were employed in determination of similarity measures with a conventional 3-layered neural network, the determined similarity measures were correlated well with the subjective ratings and the precision of retrieving diagnostically relevant images was comparable with that of the conventional method using handcrafted features. By using CNN for determination of similarity measure directly, the result was also comparable. By optimizing the network parameters, results may be further improved. The proposed method has a potential usefulness in determination of similarity measure without precise lesion outlines for retrieval of similar mass images on mammograms.

Immuno capture PCR for rapid and sensitive identification of pathogenic Bacillus anthracis.

PubMed

Makam, Shivakiran S; Majumder, Saugata; Kingston, Joseph J; Urs, Radhika M; Tuteja, Urmil; Sripathi, Murali H; Batra, Harsh V

2013-12-01

Immuno capture PCR (IPCR) is a technique capable of detecting the pathogens with high specificity and sensitivity. Rapid and accurate detection of Bacillus anthracis was achieved using anti-EA1 antibodies to capture the cells and two primer sets targeting the virulence factors of the pathogen i.e., protective antigen (pag) and capsule (cap) in an IPCR format. Monoclonal antibodies specific to B. anthracis were generated against extractable antigen 1 protein and used as capture antibody onto 96 well polystyrene plates. Following the binding of the pathogen, the DNA extraction was carried out in the well itself and further processed for PCR assay. We compared IPCR described here with conventional duplex PCR using the same primers and sandwich ELISA using the monoclonal antibodies developed in the present study. IPCR was capable of detecting as few as 10 and 100 cfu ml⁻¹ of bacterial cells and spores, respectively. IPCR was found to be 2-3 logs more sensitive than conventional duplex PCR and the sandwich ELISA. The effect of other bacteria and any organic materials on IPCR was also analyzed and found that this method was robust with little change in the sensitivity in the presence of interfering agents. Moreover, we could demonstrate a simple process of microwave treatment for spore disruption which otherwise are resistant to chemical treatments. Also, the IPCR could clearly distinguish the pathogenic and nonpathogenic strains of B. anthracis in the same assay. This can help in saving resources on unnecessary decontamination procedures during false alarms.

The effects of temperature and frequencies in ultrasound assisted extraction of phycocyanin from microalgae Spirulina sp

NASA Astrophysics Data System (ADS)

Hadiyanto, Suttrisnorhadi, Sutanto, Heri; Suzery, Meiny; Soetrisnanto, Danny; Azizah, Nur

2015-12-01

Microalgae Spirulina sp has been identified as source of protein and other high added value compounds. One of the compounds is phycocyanin as also known for antioxidant use. The extraction of this compound by using conventional method (soxhlet extraction) resulted low yield and longer processing time. This research was aimed to extract phycocyanin by using an extraction assisted by ultrasound irradiation. The extraction was performed by using variable of ultrasound frequency and extraction temperature and ethanol was used as a solvent. The result showed that yield of phycocyanin extracted by conventional method was 11.13% while the ultrasound irradiation could increase the yield up to 15.61% at constant frequency of 42 kHz, while the optimum temperature was obtained at 45°C. The analysis of variable interactions showed that both temperature and time has an interaction and temperature was the highest variable in increasing the yield. The conclusion of this research was the ultrasound could improve significantly the efficiency of extraction as well as activity of phycocyanin extracted from microalgae.

The effects of temperature and frequencies in ultrasound assisted extraction of phycocyanin from microalgae Spirulina sp

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

Hadiyanto,, E-mail: hadiyanto@live.undip.ac.id; Suttrisnorhadi,; Soetrisnanto, Danny

Microalgae Spirulina sp has been identified as source of protein and other high added value compounds. One of the compounds is phycocyanin as also known for antioxidant use. The extraction of this compound by using conventional method (soxhlet extraction) resulted low yield and longer processing time. This research was aimed to extract phycocyanin by using an extraction assisted by ultrasound irradiation. The extraction was performed by using variable of ultrasound frequency and extraction temperature and ethanol was used as a solvent. The result showed that yield of phycocyanin extracted by conventional method was 11.13% while the ultrasound irradiation could increasemore » the yield up to 15.61% at constant frequency of 42 kHz, while the optimum temperature was obtained at 45°C. The analysis of variable interactions showed that both temperature and time has an interaction and temperature was the highest variable in increasing the yield. The conclusion of this research was the ultrasound could improve significantly the efficiency of extraction as well as activity of phycocyanin extracted from microalgae.« less

Aviation accident forensic assessment : comprehensive single-extraction urine screening procedure : final report.

DOT National Transportation Integrated Search

1996-05-01

This paper describes a new single extraction screening procedure that was developed to identify as many drugs as possible in urine, with minimal effort and cost. Urine specimens are hydrolyzed and the specimen is then extracted using commercially pur...

Control of damping-off of organic and conventional cucumber with extracts from a plant-associated bacterium rivals a seed treatment pesticide

USDA-ARS?s Scientific Manuscript database

Environmentally friendly control measures are needed for soilborne diseases of crops grown in organic and conventional production systems. We tested ethanol extracts from cultures of Serratia marcescens N4-5 and N2-4, Burkholderia cepacia BC-1 and BC-2, and B. ambifaria BC-F for control of damping-o...

The effect of different solvents and number of extraction steps on the polyphenol content and antioxidant capacity of basil leaves (Ocimum basilicum L.) extracts.

PubMed

Złotek, Urszula; Mikulska, Sylwia; Nagajek, Małgorzata; Świeca, Michał

2016-09-01

The objectives of this study were to determine best conditions for the extraction of phenolic compounds from fresh, frozen and lyophilized basil leaves. The acetone mixtures with the highest addition of acetic acid extracted most of the phenolic compounds when fresh and freeze-dried material have been used. The three times procedure was more effective than once shaking procedure in most of the extracts obtained from fresh basil leaves - unlike the extracts derived from frozen material. Surprisingly, there were not any significant differences in the content of phenolics between the two used procedures in the case of lyophilized basil leaves used for extraction. Additionally, the positive correlation between the phenolic compounds content and antioxidant activity of the studied extracts has been noted. It is concluded that the acetone mixtures were more effective than the methanol ones for polyphenol extraction. The number of extraction steps in most of the cases was also a statistically significant factor affecting the yield of phenolic extraction as well as antioxidant potential of basil leaf extracts.

Performance of Single-Use FlexorVue vs Reusable BoaVision Ureteroscope for Visualization of Calices and Stone Extraction in an Artificial Kidney Model.

PubMed

Schlager, Daniel; Hein, Simon; Obaid, Moaaz Abdulghani; Wilhelm, Konrad; Miernik, Arkadiusz; Schoenthaler, Martin

2017-11-01

To evaluate and compare Flexor ® Vue™, a semidisposable endoscopic deflection system with disposable ureteral sheath and reusable visualization source, and a nondisposable fiber optic ureteroscope in a standard in vitro setting. FlexorVue and a reusable fiber optic flexible ureteroscope were each tested in an artificial kidney model. The experimental setup included the visualization of colored pearls and the extraction of calculi with two different extraction devices (NCircle ® and NGage ® ). The procedures were performed by six experienced surgeons. Visualization time, access to calices, successful stone retraction, and time required were recorded. In addition, the surgeons' workload and subjective performance were determined according to the National Aeronautics and Space Administration-task load index (NASA-TLX). We referred to the Likert scale to assess maneuverability, handling, and image quality. Nearly all calices (99%) were correctly identified using the reusable scope, indicating full kidney access, whereas 74% of the calices were visualized using FlexorVue, of which 81% were correctly identified. Access to the lower poles of the kidney model was significantly less likely with the disposable device, and time to completion was significantly longer (755 s vs 153 s, p < 0.001). The stone clearance success rate with the disposable device was 23% using the NGage and 13% using the NCircle basket. Overall NASA-TLX scores were significantly higher using FlexorVue. The conventional reusable device also demonstrated superior maneuverability, handling, and image quality. FlexorVue offers a semidisposable deflecting endoscopic system allowing basic ureteroscopic and cystoscopic procedures. For its use as an addition or replacement for current reusable scopes, it requires substantial technical improvements.

Activated charcoal-mediated RNA extraction method for Azadirachta indica and plants highly rich in polyphenolics, polysaccharides and other complex secondary compounds

PubMed Central

2013-01-01

Background High quality RNA is a primary requisite for numerous molecular biological applications but is difficult to isolate from several plants rich in polysaccharides, polyphenolics and other secondary metabolites. These compounds either bind with nucleic acids or often co-precipitate at the final step and many times cannot be removed by conventional methods and kits. Addition of vinyl-pyrollidone polymers in extraction buffer efficiently removes polyphenolics to some extent, but, it failed in case of Azadirachta indica and several other medicinal and aromatic plants. Findings Here we report the use of adsorption property of activated charcoal (0.03%–0.1%) in RNA isolation procedures to remove complex secondary metabolites and polyphenolics to yield good quality RNA from Azadirachta indica. We tested and validated our modified RNA isolation method across 21 different plants including Andrographis paniculata, Aloe vera, Rosa damascena, Pelargonium graveolens, Phyllanthus amarus etc. from 13 other different families, many of which are considered as tough system for isolating RNA. The A260/280 ratio of the extracted RNA ranged between 1.8-2.0 and distinct 28S and 18S ribosomal RNA bands were observed in denaturing agarose gel electrophoresis. Analysis using Agilent 2100 Bioanalyzer revealed intact total RNA yield with very good RNA Integrity Number. Conclusions The RNA isolated by our modified method was found to be of high quality and amenable for sensitive downstream molecular applications like subtractive library construction and RT-PCR. This modified RNA isolation procedure would aid and accelerate the biotechnological studies in complex medicinal and aromatic plants which are extremely rich in secondary metabolic compounds. PMID:23537338

Tillandsia stricta Sol (Bromeliaceae) leaves as monitors of airborne particulate matter-A comparative SEM methods evaluation: Unveiling an accurate and odd HP-SEM method.

PubMed

de Oliveira, Martha Lima; de Melo, Edésio José Tenório; Miguens, Flávio Costa

2016-09-01

Airborne particulate matter (PM) has been included among the most important air pollutants by governmental environment agencies and academy researchers. The use of terrestrial plants for monitoring PM has been widely accepted, particularly when it is coupled with SEM/EDS. Herein, Tillandsia stricta leaves were used as monitors of PM, focusing on a comparative evaluation of Environmental SEM (ESEM) and High-Pressure SEM (HPSEM). In addition, specimens air-dried at formaldehyde atmosphere (AD/FA) were introduced as an SEM procedure. Hydrated specimen observation by ESEM was the best way to get information from T. stricta leaves. If any artifacts were introduced by AD/FA, they were indiscernible from those caused by CPD. Leaf anatomy was always well preserved. PM density was determined on adaxial and abaxial leaf epidermis for each of the SEM proceedings. When compared with ESEM, particle extraction varied from 0 to 20% in air-dried leaves while 23-78% of particles deposited on leaves surfaces were extracted by CPD procedures. ESEM was obviously the best choice over other methods but morphological artifacts increased in function of operation time while HPSEM operation time was without limit. AD/FA avoided the shrinkage observed in the air-dried leaves and particle extraction was low when compared with CPD. Structural and particle density results suggest AD/FA as an important methodological approach to air pollution biomonitoring that can be widely used in all electron microscopy labs. Otherwise, previous PM assessments using terrestrial plants as biomonitors and performed by conventional SEM could have underestimated airborne particulate matter concentration. © 2016 Wiley Periodicals, Inc.

Gas pressure assisted microliquid-liquid extraction coupled online to direct infusion mass spectrometry: a new automated screening platform for bioanalysis.

PubMed

Raterink, Robert-Jan; Witkam, Yoeri; Vreeken, Rob J; Ramautar, Rawi; Hankemeier, Thomas

2014-10-21

In the field of bioanalysis, there is an increasing demand for miniaturized, automated, robust sample pretreatment procedures that can be easily connected to direct-infusion mass spectrometry (DI-MS) in order to allow the high-throughput screening of drugs and/or their metabolites in complex body fluids like plasma. Liquid-Liquid extraction (LLE) is a common sample pretreatment technique often used for complex aqueous samples in bioanalysis. Despite significant developments that have been made in automated and miniaturized LLE procedures, fully automated LLE techniques allowing high-throughput bioanalytical studies on small-volume samples using direct infusion mass spectrometry, have not been matured yet. Here, we introduce a new fully automated micro-LLE technique based on gas-pressure assisted mixing followed by passive phase separation, coupled online to nanoelectrospray-DI-MS. Our method was characterized by varying the gas flow and its duration through the solvent mixture. For evaluation of the analytical performance, four drugs were spiked to human plasma, resulting in highly acceptable precision (RSD down to 9%) and linearity (R(2) ranging from 0.990 to 0.998). We demonstrate that our new method does not only allow the reliable extraction of analytes from small sample volumes of a few microliters in an automated and high-throughput manner, but also performs comparable or better than conventional offline LLE, in which the handling of small volumes remains challenging. Finally, we demonstrate the applicability of our method for drug screening on dried blood spots showing excellent linearity (R(2) of 0.998) and precision (RSD of 9%). In conclusion, we present the proof of principe of a new high-throughput screening platform for bioanalysis based on a new automated microLLE method, coupled online to a commercially available nano-ESI-DI-MS.

A solid-phase extraction procedure coupled to 1H NMR, with chemometric analysis, to seek reliable markers of the botanical origin of honey.

PubMed

Beretta, Giangiacomo; Caneva, Enrico; Regazzoni, Luca; Bakhtyari, Nazanin Golbamaki; Maffei Facino, Roberto

2008-07-14

The aim of this work was to establish an analytical method for identifying the botanical origin of honey, as an alternative to conventional melissopalynological, organoleptic and instrumental methods (gas-chromatography coupled to mass spectrometry (GC-MS), high-performance liquid chromatography HPLC). The procedure is based on the (1)H nuclear magnetic resonance (NMR) profile coupled, when necessary, with electrospray ionisation-mass spectrometry (ESI-MS) and two-dimensional NMR analyses of solid-phase extraction (SPE)-purified honey samples, followed by chemometric analyses. Extracts of 44 commercial Italian honeys from 20 different botanical sources were analyzed. Honeydew, chestnut and linden honeys showed constant, specific, well-resolved resonances, suitable for use as markers of origin. Honeydew honey contained the typical resonances of an aliphatic component, very likely deriving from the plant phloem sap or excreted into it by sap-sucking aphids. Chestnut honey contained the typical signals of kynurenic acid and some structurally related metabolite. In linden honey the (1)H NMR profile gave strong signals attributable to the mono-terpene derivative cyclohexa-1,3-diene-1-carboxylic acid (CDCA) and to its 1-O-beta-gentiobiosyl ester (CDCA-GBE). These markers were not detectable in the other honeys, except for the less common nectar honey from rosa mosqueta. We compared and analyzed the data by multivariate techniques. Principal component analysis found different clusters of honeys based on the presence of these specific markers. The results, although obviously only preliminary, suggest that the (1)H NMR profile (with HPLC-MS analysis when necessary) can be used as a reference framework for identifying the botanical origin of honey.

Mobility of arsenic and its compounds in soil and soil solution: the effect of soil pretreatment and extraction methods.

PubMed

Száková, J; Tlustos, P; Goessler, W; Frková, Z; Najmanová, J

2009-12-30

The effect of soil extraction procedures and/or sample pretreatment (drying, freezing of the soil sample) on the extractability of arsenic and its compounds was tested. In the first part, five extraction procedures were compared with following order of extractable arsenic portions: 2M HNO(3)>0.43 M CH(3)COOH>or=0.05 M EDTA>or=Mehlich III (0.2M CH(3)COOH+0.25 M NH(4)NO(3)+0.013 M HNO(3)+0.015 M NH(4)F+0.001 M EDTA) extraction>water). Additionally, two methods of soil solution sampling were compared, centrifugation of saturated soil and the use of suction cups. The results showed that different sample pretreatments including soil solution sampling could lead to different absolute values of mobile arsenic content in soils. However, the interpretation of the data can lead to similar conclusions as apparent from the comparison of the soil solution sampling methods (r=0.79). For determination of arsenic compounds mild extraction procedures (0.05 M (NH(4))(2)SO(4), 0.01 M CaCl(2), and water) and soil solution sampling using suction cups were compared. Regarding the real soil conditions the extraction of fresh samples and/or in situ collection of soil solution are preferred among the sample pretreatments and/or soil extraction procedures. However, chemical stabilization of the solutions should be allowed and included in the analytical procedures for determination of individual arsenic compounds.

Rapid Solid-Liquid Dynamic Extraction (RSLDE): a New Rapid and Greener Method for Extracting Two Steviol Glycosides (Stevioside and Rebaudioside A) from Stevia Leaves.

PubMed

Gallo, Monica; Vitulano, Manuela; Andolfi, Anna; DellaGreca, Marina; Conte, Esterina; Ciaravolo, Martina; Naviglio, Daniele

2017-06-01

Stevioside and rebaudioside A are the main diterpene glycosides present in the leaves of the Stevia rebaudiana plant, which is used in the production of foods and low-calorie beverages. The difficulties associated with their extraction and purification are currently a problem for the food processing industries. The objective of this study was to develop an effective and economically viable method to obtain a high-quality product while trying to overcome the disadvantages derived from the conventional transformation processes. For this reason, extractions were carried out using a conventional maceration (CM) and a cyclically pressurized extraction known as rapid solid-liquid dynamic extraction (RSLDE) by the Naviglio extractor (NE). After only 20 min of extraction using the NE, a quantity of rebaudioside A and stevioside equal to 1197.8 and 413.6 mg/L was obtained, respectively, while for the CM, the optimum time was 90 min. From the results, it can be stated that the extraction process by NE and its subsequent purification developed in this study is a simple, economical, environmentally friendly method for producing steviol glycosides. Therefore, this method constitutes a valid alternative to conventional extraction by reducing the extraction time and the consumption of toxic solvents and favouring the use of the extracted metabolites as food additives and/or nutraceuticals. As an added value and of local interest, the experiment was carried out on stevia leaves from the Benevento area (Italy), where a high content of rebaudioside A was observed, which exhibits a sweet taste compared to stevioside, which has a significant bitter aftertaste.

Development of a needle driver with multiple degrees of freedom for neonatal laparoscopic surgery.

PubMed

Ishimaru, Tetsuya; Takazawa, Shinya; Uchida, Hiroo; Kawashima, Hiroshi; Fujii, Masahiro; Harada, Kanako; Sugita, Naohiko; Mitsuishi, Mamoru; Iwanaka, Tadashi

2013-07-01

The aims of this study were to develop a thin needle driver with multiple degrees of freedom and to evaluate its efficacy in multidirectional suturing compared with a conventional needle driver. The tip (15 mm) of the novel user-friendly needle driver (3.5 mm in diameter) has three degrees of freedom for grasping, rotation, and deflection. Six pediatric surgeons performed two kinds of suturing tasks in a dry box: three stitches in continuous suturing that were perpendicular or parallel to the insertion direction of the instrument, first using the novel instrument, then using a conventional instrument, and finally using the novel instrument again. The accuracy of insertion and exit compared with the target points and the procedure time were measured. In the conventional and novel procedures the mean gaps from the insertion point to the target in perpendicular suturing were 0.8 mm and 0.7 mm, respectively; in parallel suturing they were 0.8 mm and 0.6 mm, respectively. The mean gaps from the exit point to the target in perpendicular suturing were 0.6 mm and 0.6 mm for conventional and novel procedures, respectively; in parallel suturing they were 0.6 mm and 0.8 mm, respectively. The procedure time for perpendicular suturing was 33 seconds and 64 seconds for conventional and novel procedures, respectively (P=.02); for parallel suturing it was 114 seconds and 91 seconds, respectively. Our novel needle driver maintained accuracy of suturing; parallel suturing with the novel driver may be easier than with the conventional one.

Application of natural deep eutectic solvents to the extraction of anthocyanins from Catharanthus roseus with high extractability and stability replacing conventional organic solvents.

PubMed

Dai, Yuntao; Rozema, Evelien; Verpoorte, Robert; Choi, Young Hae

2016-02-19

Natural deep eutectic solvents (NADES) have attracted a great deal of attention in recent times as promising green media. They are generally composed of neutral, acidic or basic compounds that form liquids of high viscosity when mixed in certain molar ratio. Despite their potential, viscosity and acid or basic nature of some ingredients may affect the extraction capacity and stabilizing ability of the target compounds. To investigate these effects, extraction with a series of NADES was employed for the analysis of anthocyanins in flower petals of Catharanthus roseus in combination with HPLC-DAD-based metabolic profiling. Along with the extraction yields of anthocyanins their stability in NADES was also studied. Multivariate data analysis indicates that the lactic acid-glucose (LGH), and 1,2-propanediol-choline chloride (PCH) NADES present a similar extraction power for anthocyanins as conventional organic solvents. Furthermore, among the NADES employed, LGH exhibits an at least three times higher stabilizing capacity for cyanidins than acidified ethanol, which facilitates their extraction and analysis process. Comparing NADES to the conventional organic solvents, in addition to their reduced environmental impact, they proved to provide higher stability for anthocyanins, and therefore have a great potential as possible alternatives to those organic solvents in health related areas such as food, pharmaceuticals and cosmetics. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of a trigonometric finite difference procedure to numerical analysis of compressive and shear buckling of orthotropic panels

NASA Technical Reports Server (NTRS)

Stein, M.; Housner, J. D.

1978-01-01

A numerical analysis developed for the buckling of rectangular orthotropic layered panels under combined shear and compression is described. This analysis uses a central finite difference procedure based on trigonometric functions instead of using the conventional finite differences which are based on polynomial functions. Inasmuch as the buckle mode shape is usually trigonometric in nature, the analysis using trigonometric finite differences can be made to exhibit a much faster convergence rate than that using conventional differences. Also, the trigonometric finite difference procedure leads to difference equations having the same form as conventional finite differences; thereby allowing available conventional finite difference formulations to be converted readily to trigonometric form. For two-dimensional problems, the procedure introduces two numerical parameters into the analysis. Engineering approaches for the selection of these parameters are presented and the analysis procedure is demonstrated by application to several isotropic and orthotropic panel buckling problems. Among these problems is the shear buckling of stiffened isotropic and filamentary composite panels in which the stiffener is broken. Results indicate that a break may degrade the effect of the stiffener to the extent that the panel will not carry much more load than if the stiffener were absent.

Simultaneous Microwave Extraction and Separation of Volatile and Non-Volatile Organic Compounds of Boldo Leaves. From Lab to Industrial Scale

PubMed Central

Petigny, Loïc; Périno, Sandrine; Minuti, Matteo; Visinoni, Francesco; Wajsman, Joël; Chemat, Farid

2014-01-01

Microwave extraction and separation has been used to increase the concentration of the extract compared to the conventional method with the same solid/liquid ratio, reducing extraction time and separate at the same time Volatile Organic Compounds (VOC) from non-Volatile Organic Compounds (NVOC) of boldo leaves. As preliminary study, a response surface method has been used to optimize the extraction of soluble material and the separation of VOC from the plant in laboratory scale. The results from the statistical analysis revealed that the optimized conditions were: microwave power 200 W, extraction time 56 min and solid liquid ratio of 7.5% of plants in water. Lab scale optimized microwave method is compared to conventional distillation, and requires a power/mass ratio of 0.4 W/g of water engaged. This power/mass ratio is kept in order to upscale from lab to pilot plant. PMID:24776762

15 CFR 717.1 - Clarification procedures; challenge inspection requests pursuant to Article IX of the Convention.

Code of Federal Regulations, 2011 CFR

2011-01-01

... COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS CWC CLARIFICATION PROCEDURES (CONSULTATIONS AND CHALLENGE... through consultation between themselves or through the Organization for the Prohibition of Chemical Weapons (OPCW). A State Party may also request the OPCW to conduct an on-site challenge inspection of any...

[Orthogonal experiment using SFE-CO2 in extraction of essential oil from fresh Houttuynia cordata and analysis of essential oil by GC-MS].

PubMed

Meng, Jiang; Dong, Xiao-ping; Zhou, Yi-sheng; Jiang, Zhi-hong; Leung, Kelvin Sze-Yin; Zhao, Zhong-zhen

2007-02-01

To optimize the extraction procedure of essential oil from H. cordata using the SFE-CO2 and analyze the chemical composition of the essential oil. The extraction procedure of essential oil from fresh H. cordata was optimized with the orthogonal experiment. Essential oil of fresh H. cordata was analysed by GC-MS. The optimize preparative procedure was as follow: essential oil of H. cordata was extracted at a temperature of 35 degrees C, pressure of 15,000 kPa for 20 min. 38 chemical components were identified and the relative contents were quantified. The optimum preparative procedure is reliable and can guarantee the quality of essential oil.

Use of feature extraction techniques for the texture and context information in ERTS imagery: Spectral and textural processing of ERTS imagery. [classification of Kansas land use

NASA Technical Reports Server (NTRS)

Haralick, R. H. (Principal Investigator); Bosley, R. J.

1974-01-01

The author has identified the following significant results. A procedure was developed to extract cross-band textural features from ERTS MSS imagery. Evolving from a single image texture extraction procedure which uses spatial dependence matrices to measure relative co-occurrence of nearest neighbor grey tones, the cross-band texture procedure uses the distribution of neighboring grey tone N-tuple differences to measure the spatial interrelationships, or co-occurrences, of the grey tone N-tuples present in a texture pattern. In both procedures, texture is characterized in such a way as to be invariant under linear grey tone transformations. However, the cross-band procedure complements the single image procedure by extracting texture information and spectral information contained in ERTS multi-images. Classification experiments show that when used alone, without spectral processing, the cross-band texture procedure extracts more information than the single image texture analysis. Results show an improvement in average correct classification from 86.2% to 88.8% for ERTS image no. 1021-16333 with the cross-band texture procedure. However, when used together with spectral features, the single image texture plus spectral features perform better than the cross-band texture plus spectral features, with an average correct classification of 93.8% and 91.6%, respectively.

Report on the study of the tax and rate treatment of renewable energy projects

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

Hadley, S.W.; Hill, L.J.; Perlack, R.D.

1993-12-01

This study was conducted in response to the requirements of Section 1205 of the Energy Policy Act of 1992 (EPACT), which states: The Secretary (of Energy), in conjunction with State regulatory commissions, shall undertake a study to determine if conventional taxation and ratemaking procedures result in economic barriers to or incentives for renewable energy power plants compared to conventional power plants. The purpose of the study, therefore, is not to compare the cost-effectiveness of different types of renewable and conventional electric generating plants. Rather, it is to determine the relative impact of conventional ratemaking and taxation procedures on the selectionmore » of renewable power plants compared to conventional ones. To make this determination, we quantify the technical and financial parameters of renewable and conventional electric generating technologies, and hold them fixed throughout the study. Then, we vary taxation and ratemaking procedures to determine their effects on the financial criteria that investor-owned electric utilities (IOUs) and nonutility electricity generators (NUGs) use to make technology-adoption decisions. In the planning process of a typical utility, the opposite is usually the case. That is, utilities typically hold ratemaking and taxation procedures constant and look for the least-cost mix of resources, varying the values of engineering and financial parameters of generating plants in the process.« less

Detection of SEA-type α-thalassemia in embryo biopsies by digital PCR.

PubMed

Lee, Ta-Hsien; Hsu, Ya-Chiung; Chang, Chia Lin

2017-08-01

Accurate and efficient pre-implantation genetic diagnosis (PGD) based on the analysis of single or oligo-cells is needed for timely identification of embryos that are affected by deleterious genetic traits in in vitro fertilization (IVF) clinics. Polymerase chain reaction (PCR) is the backbone of modern genetic diagnoses, and a spectrum of PCR-based techniques have been used to detect various thalassemia mutations in prenatal diagnosis (PND) and PGD. Among thalassemias, SEA-type α-thalassemia is the most common variety found in Asia, and can lead to Bart's hydrops fetalis and serious maternal complications. To formulate an efficient digital PCR for clinical diagnosis of SEA-type α-thalassemia in cultured embryos, we conducted a pilot study to detect the α-globin and SEA-type deletion alleles in blastomere biopsies with a highly sensitive microfluidics-based digital PCR method. Genomic DNA from embryo biopsy samples were extracted, and crude DNA extracts were first amplified by a conventional PCR procedure followed by a nested PCR reaction with primers and probes that are designed for digital PCR amplification. Analysis of microfluidics-based PCR reactions showed that robust signals for normal α-globin and SEA-type deletion alleles, together with an internal control gene, can be routinely generated using crude embryo biopsies after a 10 6 -fold dilution of primary PCR products. The SEA-type deletion in cultured embryos can be sensitively diagnosed with the digital PCR procedure in clinics. The adoption of this robust PGD method could prevent the implantation of IVF embryos that are destined to develop Bart's hydrops fetalis in a timely manner. The results also help inform future development of a standard digital PCR procedure for cost-effective PGD of α-thalassemia in a standard IVF clinic. Copyright © 2017. Published by Elsevier B.V.

A procedure to estimate proximate analysis of mixed organic wastes.

PubMed

Zaher, U; Buffiere, P; Steyer, J P; Chen, S

2009-04-01

In waste materials, proximate analysis measuring the total concentration of carbohydrate, protein, and lipid contents from solid wastes is challenging, as a result of the heterogeneous and solid nature of wastes. This paper presents a new procedure that was developed to estimate such complex chemical composition of the waste using conventional practical measurements, such as chemical oxygen demand (COD) and total organic carbon. The procedure is based on mass balance of macronutrient elements (carbon, hydrogen, nitrogen, oxygen, and phosphorus [CHNOP]) (i.e., elemental continuity), in addition to the balance of COD and charge intensity that are applied in mathematical modeling of biological processes. Knowing the composition of such a complex substrate is crucial to study solid waste anaerobic degradation. The procedure was formulated to generate the detailed input required for the International Water Association (London, United Kingdom) Anaerobic Digestion Model number 1 (IWA-ADM1). The complex particulate composition estimated by the procedure was validated with several types of food wastes and animal manures. To make proximate analysis feasible for validation, the wastes were classified into 19 types to allow accurate extraction and proximate analysis. The estimated carbohydrates, proteins, lipids, and inerts concentrations were highly correlated to the proximate analysis; correlation coefficients were 0.94, 0.88, 0.99, and 0.96, respectively. For most of the wastes, carbohydrate was the highest fraction and was estimated accurately by the procedure over an extended range with high linearity. For wastes that are rich in protein and fiber, the procedure was even more consistent compared with the proximate analysis. The new procedure can be used for waste characterization in solid waste treatment design and optimization.

Biological activity and chemical profile of Lavatera thuringiaca L. extracts obtained by different extraction approaches.

PubMed

Mašković, Pavle Z; Veličković, Vesna; Đurović, Saša; Zeković, Zoran; Radojković, Marija; Cvetanović, Aleksandra; Švarc-Gajić, Jaroslava; Mitić, Milan; Vujić, Jelena

2018-01-01

Lavatera thuringiaca L. is herbaceous perennial plant from Malvaceae family, which is known for its biological activity and richness in polyphenolic compounds. Despite this, the information regarding the biological activity and chemical profile is still insufficient. Aim of this study was to investigate biological potential and chemical profile of Lavatera thuringiaca L., as well as influence of applied extraction technique on them. Two conventional and four non-conventional extraction techniques were applied in order to obtain extracts rich in bioactive compound. Extracts were further tested for total phenolics, flavonoids, condensed tannins, gallotannins and anthocyanins contents using spectrophotometric assays. Polyphenolic profile was established using HPLC-DAD analysis. Biological activity was investigated regarding antioxidant, cytotoxic and antibacterial activities. Four antioxidant assays were applied as well as three different cell lines for cytotoxic and fifteen bacterial strain for antibacterial activity. Results showed that subcritical water extraction (SCW) dominated over the other extraction techniques, where SCW extract exhibited the highest biological activity. Study indicates that plant Lavatera thuringiaca L. may be used as a potential source of biologically compounds. Copyright © 2017 Elsevier GmbH. All rights reserved.

21 CFR 173.280 - Solvent extraction process for citric acid.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Solvent extraction process for citric acid. 173..., Lubricants, Release Agents and Related Substances § 173.280 Solvent extraction process for citric acid. A solvent extraction process for recovery of citric acid from conventional Aspergillus niger fermentation...

Viability testing of material derived from Mycobacterium tuberculosis prior to removal from a Containment Level-III Laboratory as part of a Laboratory Risk Assessment Program

PubMed Central

Blackwood, Kym S; Burdz, Tamara V; Turenne, Christine Y; Sharma, Meenu K; Kabani, Amin M; Wolfe, Joyce N

2005-01-01

Background In the field of clinical mycobacteriology, Mycobacterium tuberculosis (MTB) can be a difficult organism to manipulate due to the restrictive environment of a containment level 3 (CL3) laboratory. Tests for rapid diagnostic work involving smears and molecular methods do not require CL3 practices after the organism has been rendered non-viable. While it has been assumed that after organism deactivation these techniques can be performed outside of a CL3, no conclusive study has consistently confirmed that the organisms are noninfectious after the theoretical 'deactivation' steps. Previous studies have shown that initial steps (such as heating /chemical fixation) may not consistently kill MTB organisms. Methods An inclusive viability study (n = 226) was undertaken to determine at which point handling of culture extraction materials does not necessitate a CL3 environment. Four different laboratory protocols tested for viability included: standard DNA extractions for IS6110 fingerprinting, crude DNA preparations for PCR by boiling and mechanical lysis, protein extractions, and smear preparations. For each protocol, laboratory staff planted a proportion of the resulting material to Bactec 12B medium that was observed for growth for 8 weeks. Results Of the 208 isolates initially tested, 21 samples grew within the 8-week period. Sixteen (7.7%) of these yielded positive results for MTB that included samples of: deactivated culture resuspensions exposed to 80°C for 20 minutes, smear preparations and protein extractions. Test procedures were consequently modified and tested again (n = 18), resulting in 0% viability. Conclusions This study demonstrates that it cannot be assumed that conventional practices (i.e. smear preparation) or extraction techniques render the organism non-viable. All methodologies, new and existing, should be examined by individual laboratories to validate the safe removal of material derived from MTB to the outside of a CL3 laboratory. This process is vital to establish in house biosafety-validated practices with the aim of protecting laboratory workers conducting these procedures. PMID:15667662

Authentication systems for securing clinical documentation workflows. A systematic literature review.

PubMed

Schwartze, J; Haarbrandt, B; Fortmeier, D; Haux, R; Seidel, C

2014-01-01

Integration of electronic signatures embedded in health care processes in Germany challenges health care service and supply facilities. The suitability of the signature level of an eligible authentication procedure is confirmed for a large part of documents in clinical practice. However, the concrete design of such a procedure remains unclear. To create a summary of usable user authentication systems suitable for clinical workflows. A Systematic literature review based on nine online bibliographic databases. Search keywords included authentication, access control, information systems, information security and biometrics with terms user authentication, user identification and login in title or abstract. Searches were run between 7 and 12 September 2011. Relevant conference proceedings were searched manually in February 2013. Backward reference search of selected results was done. Only publications fully describing authentication systems used or usable were included. Algorithms or purely theoretical concepts were excluded. Three authors did selection independently. DATA EXTRACTION AND ASSESSMENT: Semi-structured extraction of system characteristics was done by the main author. Identified procedures were assessed for security and fulfillment of relevant laws and guidelines as well as for applicability. Suitability for clinical workflows was derived from the assessments using a weighted sum proposed by Bonneau. Of 7575 citations retrieved, 55 publications meet our inclusion criteria. They describe 48 different authentication systems; 39 were biometric and nine graphical password systems. Assessment of authentication systems showed high error rates above European CENELEC standards and a lack of applicability of biometric systems. Graphical passwords did not add overall value compared to conventional passwords. Continuous authentication can add an additional layer of safety. Only few systems are suitable partially or entirely for use in clinical processes. Suitability strongly depends on national or institutional requirements. Four authentication systems seem to fulfill requirements of authentication procedures for clinical workflows. Research is needed in the area of continuous authentication with biometric methods. A proper authentication system should combine all factors of authentication implementing and connecting secure individual measures.

Comparative Evaluation of Different Cell Lysis and Extraction Methods for Studying Benzo(a)pyrene Metabolism in HT-29 Colon Cancer Cell Cultures

PubMed Central

Myers, Jeremy N.; Rekhadevi, Perumalla V.; Ramesh, Aramandla

2011-01-01

Lysis and extraction of cells are essential sample processing steps for investigations pertaining to metabolism of xenobiotics in cell culture studies. Of particular importance to these procedures are maintaining high lysis efficiency and analyte integrity as they influence the qualitative and quantitative distribution of drug and toxicant metabolites in the intra- and extracellular milieus. In this study we have compared the efficiency of different procedures viz. homogenization, sonication, bead beating, and molecular grinding resin treatment for disruption of HT-29 colon cells exposed to benzo(a)pyrene (BaP), a polycyclic aromatic hydrocarbon (PAH) compound and a suspected colon carcinogen. Also, we have evaluated the efficiency of various procedures for extracting BaP parent compound/metabolites from colon cells and culture media prior to High Performance Liquid Chromatography (HPLC) analyses. The extraction procedures include solid phase extraction, solid-supported liquid- liquid extraction, liquid-liquid extraction, and homogeneous liquid- liquid extraction. Our findings showed that bead-beating in combination with detergent treatment of cell pellet coupled with liquid-liquid extraction yielded greater concentrations of BaP metabolites compared to the other methods employed. Our method optimization strategy revealed that disruption of HT-29 colon cells by a combination of mechanical and chemical lysis followed by liquid-liquid extraction is efficient and robust enough for analyzing BaP metabolites from cell culture studies. PMID:21865728

Manufacturing implant supported auricular prostheses by rapid prototyping techniques.

PubMed

Karatas, Meltem Ozdemir; Cifter, Ebru Demet; Ozenen, Didem Ozdemir; Balik, Ali; Tuncer, Erman Bulent

2011-08-01

Maxillofacial prostheses are usually fabricated on the models obtained following the impression procedures. Disadvantages of conventional impression techniques used in production of facial prosthesis are deformation of soft tissues caused by impression material and disturbance of the patient due to. Additionally production of prosthesis by conventional methods takes longer time. Recently, rapid prototyping techniques have been developed for extraoral prosthesis in order to reduce these disadvantages of conventional methods. Rapid prototyping technique has the potential to simplify the procedure and decrease the laboratory work required. It eliminates the need for measurement impression procedures and preparation of wax model to be performed by prosthodontists themselves In the near future this technology will become a standard for fabricating maxillofacial prostheses.

Determination of Microalgal Lipid Content and Fatty Acid for Biofuel Production

PubMed Central

Chen, Zhipeng; Wang, Lingfeng

2018-01-01

Biofuels produced from microalgal biomass have received growing worldwide recognition as promising alternatives to conventional petroleum-derived fuels. Among the processes involved, the downstream refinement process for the extraction of lipids from biomass greatly influences the sustainability and efficiency of the entire biofuel system. This review summarizes and compares the current techniques for the extraction and measurement of microalgal lipids, including the gravimetric methods using organic solvents, CO2-based solvents, ionic liquids and switchable solvents, Nile red lipid visualization method, sulfo-phospho-vanillin method, and the thin-layer chromatography method. Each method has its own competitive advantages and disadvantages. For example, the organic solvents-based gravimetric method is mostly used and frequently employed as a reference standard to validate other methods, but it requires large amounts of samples and is time-consuming and expensive to recover solvents also with low selectivity towards desired products. The pretreatment approaches which aimed to disrupt cells and support subsequent lipid extraction through bead beating, microwave, ultrasonication, chemical methods, and enzymatic disruption are also introduced. Moreover, the principles and procedures for the production and quantification of fatty acids are finally described in detail, involving the preparation of fatty acid methyl esters and their quantification and composition analysis by gas chromatography.

Determination of α-tocopherol by reversed-phase HPLC in feed and animal-derived foods without saponification.

PubMed

Claeys, Erik; Vossen, Els; De Smet, Stefaan

2016-01-30

The analysis of α-tocopherol in feed and animal-derived foods usually involves a saponification step. However, since saponification often leads to losses of α-tocopherol, a method for the determination of α-tocopherol in feed and in animal-derived foods was developed without a saponification step. In this method, α-tocopherol is extracted with hot ethanol and the co-extracted fat is removed by centrifugation. Removal of the fat fraction is made possible by the addition of water, to achieve an ethanol:water ratio of 40:7, followed by cooling on ice before centrifugation. This procedure allows removal of the fat fraction, while α-tocopherol is retained. Matrices differing in gross composition and α-tocopherol content were analyzed: fresh pork, cooked ham, subcutaneous fat, liver, egg yolk, milk and a compound pig feed. Higher α-tocopherol concentrations were found for this novel method compared to a conventional method with saponification, particularly for subcutaneous fat (P < 0.05). Recoveries were higher (P < 0.05) for the novel method (82-103%), compared to the saponification method (66-90%; for subcutaneous fat < 25%). Determining α-tocopherol in feed and animal-derived foods using pure ethanol without saponification results in higher extraction yields and recoveries compared to the saponification method. © 2015 Society of Chemical Industry.

Fast determination of four polar contaminants in soy nutraceutical products by liquid chromatography coupled to tandem mass spectrometry.

PubMed

Domingos Alves, Renata; Romero-González, Roberto; López-Ruiz, Rosalía; Jiménez-Medina, M L; Garrido Frenich, Antonia

2016-11-01

An analytical method based on a modified QuPPe (quick polar pesticide) extraction procedure coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was evaluated for the determination of four polar compounds (chlorate, fosetyl-Al, maleic hydrazide, and perchlorate) in nutraceutical products obtained from soy. Experimental conditions including extraction such as solvent, acidification, time, and clean-up sorbents were varied. Acidified acetonitrile (1 % formic acid, v/v) was used as extraction solvent instead of methanol (conventional QuPPe), which provides a doughy mixture which cannot be injected into the LC. Clean-up or derivatization steps were avoided. For analysis, several stationary phases were evaluated and Hypercarb (porous graphitic carbon) provided the best results. The optimized method was validated and recoveries ranged between 46 and 119 %, and correction factors can be used for quantification purposes bearing in mind that inter-day precision was equal to or lower than 17 %. Limits of quantification (LOQs) ranged from 4 to 100 μg kg -1 . Soy-based nutraceutical products were analyzed and chlorate was detected in five samples at concentrations between 63 and 1642 μg kg -1 . Graphical Abstract Analysis of polar compounds in soy-based nutraceutical products.

Pulpal Effects of Enamel Ablation With a Microsecond Pulsed λ=9.3-μm CO2 Laser

PubMed Central

Staninec, Michal; Darling, Cynthia L.; Goodis, Harold E.; Pierre, Daniel; Cox, Darren P.; Fan, Kenneth; Larson, Michael; Parisi, Renaldo; Hsu, Dennis; Manesh, Saman K.; Ho, Chi; Hosseini, Mehran; Fried, Daniel

2011-01-01

Background and Objectives In vitro studies have shown that CO2 lasers operating at the highly absorbed 9.3 and 9.6-μm wavelengths with a pulse duration in the range of 10–20-microsecond are well suited for the efficient ablation of enamel and dentin with minimal peripheral thermal damage. Even though these CO2 lasers are highly promising, they have yet to receive FDA approval. Clinical studies are necessary to determine if excessive heat deposition in the tooth may have any detrimental pulpal effects, particularly at higher ablative fluencies. The purpose of this study was to evaluate the pulpal safety of laser irradiation of tooth occlusal surfaces under the conditions required for small conservative preparations confined to enamel. Study Design/Materials and Methods Test subjects requiring removal of third molar teeth were recruited and teeth scheduled for extraction were irradiated using a pulsed CO2 laser at a wavelength of 9.3 μm operating at 25 or 50 Hz using a incident fluence of 20 J/cm2 for a total of 3,000 laser pulses (36 J) for both rates with water cooling. Two control groups were used, one with no treatment and one with a small cut made with a conventional high-speed hand-piece. No anesthetic was used for any of the procedures and tooth vitality was evaluated prior to treatment by heat, cold and electrical testing. Short term effects were observed on teeth extracted within 72 hours after treatment and long term effects were observed on teeth extracted 90 days after treatment. The pulps of the teeth were fixed with formalin immediately after extraction and subjected to histological examination. Additionally, micro-thermocouple measurements were used to estimate the potential temperature rise in the pulp chamber of extracted teeth employing the same irradiation conditions used in vivo. Results Pulpal thermocouple measurements showed the internal temperature rise in the tooth was within safe limits, 3.3±4°C without water cooling versus 1.7±6°C with water-cooling, n=25, P<0.05. None of the control or treatment groups showed any deleterious effects on pulpal tissues and none of the 29 test-subjects felt pain or discomfort after the procedure. Only two test-subjects felt discomfort from “cold sensitivity” during the procedure caused by the water-spray. Conclusion It appears that this CO2 laser can ablate enamel safely without harming the pulp under the rate of energy deposition employed in this study. Lasers Surg. PMID:19347946

Pulpal effects of enamel ablation with a microsecond pulsed lambda = 9.3-microm CO2 laser.

PubMed

Staninec, Michal; Darling, Cynthia L; Goodis, Harold E; Pierre, Daniel; Cox, Darren P; Fan, Kenneth; Larson, Michael; Parisi, Renaldo; Hsu, Dennis; Manesh, Saman K; Ho, Chi; Hosseini, Mehran; Fried, Daniel

2009-04-01

In vitro studies have shown that CO2 lasers operating at the highly absorbed 9.3 and 9.6-microm wavelengths with a pulse duration in the range of 10-20-microsecond are well suited for the efficient ablation of enamel and dentin with minimal peripheral thermal damage. Even though these CO2 lasers are highly promising, they have yet to receive FDA approval. Clinical studies are necessary to determine if excessive heat deposition in the tooth may have any detrimental pulpal effects, particularly at higher ablative fluencies. The purpose of this study was to evaluate the pulpal safety of laser irradiation of tooth occlusal surfaces under the conditions required for small conservative preparations confined to enamel. Test subjects requiring removal of third molar teeth were recruited and teeth scheduled for extraction were irradiated using a pulsed CO2 laser at a wavelength of 9.3 microm operating at 25 or 50 Hz using a incident fluence of 20 J/cm(2) for a total of 3,000 laser pulses (36 J) for both rates with water cooling. Two control groups were used, one with no treatment and one with a small cut made with a conventional high-speed hand-piece. No anesthetic was used for any of the procedures and tooth vitality was evaluated prior to treatment by heat, cold and electrical testing. Short term effects were observed on teeth extracted within 72 hours after treatment and long term effects were observed on teeth extracted 90 days after treatment. The pulps of the teeth were fixed with formalin immediately after extraction and subjected to histological examination. Additionally, micro-thermocouple measurements were used to estimate the potential temperature rise in the pulp chamber of extracted teeth employing the same irradiation conditions used in vivo. Pulpal thermocouple measurements showed the internal temperature rise in the tooth was within safe limits, 3.3+/-1.4 degrees C without water cooling versus 1.7+/-1.6 degrees C with water-cooling, n = 25, P<0.05. None of the control or treatment groups showed any deleterious effects on pulpal tissues and none of the 29 test-subjects felt pain or discomfort after the procedure. Only two test-subjects felt discomfort from "cold sensitivity" during the procedure caused by the water-spray. It appears that this CO2 laser can ablate enamel safely without harming the pulp under the rate of energy deposition employed in this study.

Ionic liquid-based microwave-assisted extraction for the determination of flavonoid glycosides in pigeon pea leaves by high-performance liquid chromatography-diode array detector with pentafluorophenyl column.

PubMed

Wei, Wei; Fu, Yu-jie; Zu, Yuan-gang; Wang, Wei; Luo, Meng; Zhao, Chun-jian; Li, Chun-ying; Zhang, Lin; Wei, Zuo-fu

2012-11-01

In this study, an ionic liquid-based microwave-assisted extraction (ILMAE) followed by high-performance liquid chromatography-diode array detector with a pentafluorophenyl column for the extraction and quantification of eight flavonoid glycosides in pigeon pea leaves is described. Compared with conventional extraction methods, ILMAE is a more effective and environment friendly method for the extraction of nature compounds from herbal plants. Nine different types of ionic liquids with different cations and anions were investigated. The results suggested that varying the anion and cation had significant effects on the extraction of flavonoid glycosides, and 1.0 M 1-butyl-3-methylimidazolium bromide ([C4MIM]Br) solution was selected as solvent. In addition, the extraction procedures were also optimized using a series of single-factor experiments. The optimum parameters were obtained as follows: extraction temperature 60°C, liquid-solid ratio 20:1 mL/g and extraction time 13 min. Moreover, an HPLC method using pentafluorophenyl column was established and validated. Good linearity was observed with the regression coefficients (r(2)) more than 0.999. The limit of detection (LODs) (S/N = 3) and limit of quantification (LOQs) (S/N = 10) for the components were less than 0.41 and 1.47 μg/mL, respectively. The inter- and intraday precisions that were used to evaluate the reproducibility and relative standard deviation (RSD) values were less than 4.57%. The recoveries were between 97.26 and 102.69%. The method was successfully used for the analysis of samples of pigeon pea leaves. In conclusion, the developed ILMAE-HPLC-diode array detector using pentafluorophenyl column method can be applied for quality control of pigeon pea leaves and related medicinal products. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

Isolation and purification of RNA from tissues rich in polyphenols, polysaccharides, and pigments of annatto (Bixa orellana L.).

PubMed

Rodrigues, Simone M; Soares, Virgínia L F; de Oliveira, Tahise M; Gesteira, Abelmon S; Otoni, Wagner C; Costa, Marcio G C

2007-11-01

The tropical plant Bixa orellana L. (annatto) produces an array of natural products, including the pigment bixin used in the food and cosmetics industries. In order to understand the biochemical and molecular basis of the biosynthesis of these natural products, a reliable method for isolating high yields of high-quality RNA is required. Here we described a successful and reproducible method for isolation and purification of high-quantity and high-quality RNA from different tissues of annatto. This protocol overcomes the usual problems associated with large amounts of polyphenols, polysaccharides, pigments, and other secondary metabolites that are not easily removed by conventional extraction procedures. Furthermore, the proposed protocol can be easily carried out in any laboratory and it could also be extended to isolate RNA from other plant species showing similar abundance of compounds that interfere with RNA extractions. The yield and quality of the RNA were monitored by spectrophotometric analysis, separation on agarose gel, Reverse Transcription-Polymerase Chain Reaction (RT-PCR), and construction of a cDNA library.

Development of a rapid screening technique for organochlorine pesticides using solvent microextraction (SME) and fast gas chromatography (GC).

PubMed

de Jager, L S; Andrews, A R

2000-11-01

A novel, fast screening method for organochlorine pesticides (OCPs) in water samples has been developed. Total analysis time was less than 9 min, allowing 11 samples to be screened per hour. The relatively new technique of solvent microextraction (SME) was used to extract and preconcentrate the pesticides into a single drop of hexane. The use of a conventional carbon dioxide cryotrap was investigated for introduction of the extract onto a micro-bore (0.1 mm) capillary column for fast GC analysis. A pulsed-discharge electron capture detector was used which yielded selective and sensitive measurement of the pesticide peaks. Fast GC conditions were optimised and tested with the previously developed SME procedure. Calibration curves yielded good linearity and concentrations down to 0.25 ng mL-1 were detectable with RSD values ranging from 12.0 to 28% and LOD for most OCPs at 0.25 ng mL-1. Spiked river water samples were tested and using the developed screen we were able to differentiate between spiked samples and samples containing no OCPs.

Extracting surface diffusion coefficients from batch adsorption measurement data: application of the classic Langmuir kinetics model.

PubMed

Chu, Khim Hoong

2017-11-09

Surface diffusion coefficients may be estimated by fitting solutions of a diffusion model to batch kinetic data. For non-linear systems, a numerical solution of the diffusion model's governing equations is generally required. We report here the application of the classic Langmuir kinetics model to extract surface diffusion coefficients from batch kinetic data. The use of the Langmuir kinetics model in lieu of the conventional surface diffusion model allows derivation of an analytical expression. The parameter estimation procedure requires determining the Langmuir rate coefficient from which the pertinent surface diffusion coefficient is calculated. Surface diffusion coefficients within the 10 -9 to 10 -6  cm 2 /s range obtained by fitting the Langmuir kinetics model to experimental kinetic data taken from the literature are found to be consistent with the corresponding values obtained from the traditional surface diffusion model. The virtue of this simplified parameter estimation method is that it reduces the computational complexity as the analytical expression involves only an algebraic equation in closed form which is easily evaluated by spreadsheet computation.

Spectrophotometric determination of paracetamol in urine with tetrahydroxycalix[4]arene as a coupling reagent and preconcentration with triton X-114 using cloud point extraction.

PubMed

Filik, Hayati; Sener, Izzet; Cekiç, Sema Demirci; Kiliç, Emine; Apak, Reşat

2006-06-01

In the present paper, conventional spectrophotometry in conjunction with cloud point extraction-preconcentration were investigated as alternative methods for paracetamol (PCT) assay in urine samples. Cloud point extraction (CPE) was employed for the preconcentration of p-aminophenol (PAP) prior to spectrophotometric determination using the non-ionic surfactant Triton X-114 (TX-114) as an extractant. The developed methods were based on acidic hydrolysis of PCT to PAP, which reacted at room temperature with 25,26,27,28-tetrahydroxycalix[4]arene (CAL4) in the presence of an oxidant (KIO(4)) to form an blue colored product. The PAP-CAL4 blue dye formed was subsequently entrapped in the surfactant micelles of Triton X-114. Cloud point phase separation with the aid of Triton X-114 induced by addition of Na(2)SO(4) solution was performed at room temperature as an advantage over other CPE assays requiring elevated temperatures. The 580 nm-absorbance maximum of the formed product was shifted bathochromically to 590 nm with CPE. The working range of 1.5-12 microg ml(-1) achieved by conventional spectrophotometry was reduced down to 0.14-1.5 microg ml(-1) with cloud point extraction, which was lower than those of most literature flow-through assays that also suffer from nonspecific absorption in the UV region. By preconcentrating 10 ml sample solution, a detection limit as low as 40.0 ng ml(-1) was obtained after a single-step extraction, achieving a preconcentration factor of 10. The stoichiometric composition of the dye was found to be 1 : 4 (PAP : CAL4). The impact of a number of parameters such as concentrations of CAL4, KIO(4), Triton X-100 (TX-100), and TX-114, extraction temperature, time periods for incubation and centrifugation, and sample volume were investigated in detail. The determination of PAP in the presence of paracetamol in micellar systems under these conditions is limited. The established procedures were successfully adopted for the determination of PCT in urine samples. Since the drug is rapidly absorbed and excreted largely in urine and its high doses have been associated with lethal hepatic necrosis and renal failure, development of a rapid, sensitive and selective assay of PCT is of vital importance for fast urinary screening and antidote administration before applying more sophisticated, but costly and laborious hyphenated instrumental techniques of HPLC-SPE-NMR-MS.

Assessment of Conventional Teaching Procedures: Implications for Gifted Learners

ERIC Educational Resources Information Center

Alenizi, Mogbel Aid K.

2016-01-01

The present research aims to assess the conventional teaching procedures in the development of mathematical skills of the students with learning difficulties. The study group was made up of all the children with academic learning disorders in KSA. The research questions have been scrutinized from the averages and the standard deviation of the…

Organic and conventional fertilisation procedures on the nitrate, antioxidants and pesticide content in parts of vegetables.

PubMed

Lima, G P P; Teixeira da Silva, Jaime A; Bernhard, A B; Pirozzi, D C Z; Fleuri, L F; Vianello, F

2012-01-01

Different parts of plant foods are generally discarded by consumers such as peel, stalk and leaves, which could however possess a nutritional value. However, few studies have analysed the composition of these marginal foods. The phenolic compound, flavonoid, polyamine, nitrate and pesticide contents of parts of vegetables that are usually discarded--but which were cultivated according to conventional and non-conventional procedures--were analysed to provide suggestions on how to improve the consumption of these parts and to reduce the production of urban solid waste. Few, but significant, differences between the two manuring procedures were observed. Higher nitrate content and the presence of organochlorine pesticides were found in conventional cultivated papaya peel, lemon balm leaves, jack fruit pulp, and beet stalk and peel. Discarded parts of plant foods such as stalk, leaves and peels can be used as a source of antioxidant compounds, such as phenolic compounds.

Highly efficient extraction of anthocyanins from grape skin using deep eutectic solvents as green and tunable media.

PubMed

Jeong, Kyung Min; Zhao, Jing; Jin, Yan; Heo, Seong Rok; Han, Se Young; Yoo, Da Eun; Lee, Jeongmi

2015-12-01

Deep eutectic solvents (DESs) were investigated as tunable, environmentally benign, yet superior extraction media to enhance the extraction of anthocyanins from grape skin, which is usually discarded as waste. Ten DESs containing choline chloride as hydrogen bond acceptor combined with different hydrogen bond donors were screened for high extraction efficiencies based on the anthocyanin extraction yields. As a result, citric acid, D-(+)-maltose, and fructose were selected as the effective DES components, and the newly designed DES, CM-6 that is composed of citric acid and D-(+)-maltose at 4:1 molar ratio, exhibited significantly higher levels of anthocyanin extraction yields than conventional extraction solvents such as 80% aqueous methanol. The final extraction method was established based on the ultrasound-assisted extraction under conditions optimized using response surface methodology. Its extraction yields were double or even higher than those of conventional methods that are time-consuming and use volatile organic solvents. Our method is truly a green method for anthocyanin extraction with great extraction efficiency using a minimal amount of time and solvent. Moreover, this study suggested that grape skin, the by-products of grape juice processing, could serve as a valuable source for safe, natural colorants or antioxidants by use of the eco-friendly extraction solvent, CM-6.

Subcritical water extraction of lipids from wet algal biomass

DOEpatents

Deng, Shuguang; Reddy, Harvind K.; Schaub, Tanner; Holguin, Francisco Omar

2016-05-03

Methods of lipid extraction from biomass, in particular wet algae, through conventionally heated subcritical water, and microwave-assisted subcritical water. In one embodiment, fatty acid methyl esters from solids in a polar phase are further extracted to increase biofuel production.

EXTRACTION OF ORGANIC CONTAMINANTS FROM MARINE SEDIMENTS AND TISSUES USING MICROWAVE ENERGY

EPA Science Inventory

In this study, we compared microwave solvent extraction (MSE) to conventional methods for extracting organic contaminants from marine sediments and tissues with high and varying moisture content. The organic contaminants measured were polychlorinated biphenyl (PCB) congeners, chl...

Antibacterial efficacy of Mangifera indica L. kernel and Ocimum sanctum L. leaves against Enterococcus faecalis dentinal biofilm

PubMed Central

Subbiya, Arunajatesan; Mahalakshmi, Krishnan; Pushpangadan, Sivan; Padmavathy, Kesavaram; Vivekanandan, Paramasivam; Sukumaran, Vridhachalam Ganapathy

2013-01-01

Introduction: The Enterococcus faecalis biofilm in the root canal makes it difficult to be eradicated by the conventional irrigants with no toxicity to the tissues. Hence, plant products with least side effects are explored for their use as irrigants in the root canal therapy. Aim: To evaluate and compare the antibacterial efficacy of Mangifera indica L. kernel (mango kernel) and Ocimum sanctum L. leaves (tulsi) extracts with conventional irrigants (5% sodium hypochlorite (NaOCl) and 2% chlorhexidine) against E. faecalis dentinal biofilm. Materials and Methods: Agar diffusion and broth microdilution assay was performed with the herbal extracts and conventional irrigants (2% chlorhexidine and 5% NaOCl) against E. faecalis planktonic cells. The assay was extended onto 3 week E. faecalis dentinal biofilm. Results: Significant reduction of colony forming units (CFU)/mL was observed for the herbal groups and the antibacterial activity of the herbal groups was at par with 5% NaOCl. Conclusions: The antibacterial activity of these herbal extracts is found to be comparable with that of conventional irrigants both on the biofilm and planktonic counterparts. PMID:24082577

77 FR 65941 - Energy Conservation Program: Test Procedures for Residential Dishwashers, Dehumidifiers, and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-31

...The U.S. Department of Energy (DOE) establishes new test procedures for residential dishwashers and dehumidifiers, and amends the currently applicable test procedure for conventional cooking products under the Energy Policy and Conservation Act. The new test procedures include provisions for measuring standby mode and off mode energy consumption, and update the provisions for measuring active mode energy consumption and, for dishwashers, water consumption. This final rule also amends the certification, compliance, and enforcement requirements for dishwashers, dehumidifiers and conventional cooking products, amends certain provisions in the currently applicable dishwasher test procedure, and eliminates an obsolete energy efficiency metric in the dishwasher test procedure and provisions in the cooking products test procedure that have become obsolete due to the elimination of standing pilot lights.

Evaluation of the efficiency of three extraction conditions for the immunochemical detection of allergenic soy proteins in different food matrices.

PubMed

Amponsah, Amma; Nayak, Balunkeswar

2018-04-01

Recent studies have shown the need to improve soy allergen extraction using different extraction conditions to ensure more accurate results in allergen detection. This study investigated some of these extraction conditions to confirm that these methods, especially ultrasound-assisted extraction (UAE) and the use of Laemmli buffer instead of the conventional extraction with phosphate-buffered saline (PBS), could be helpful in improving the extraction step in allergen detection. Higher total soluble protein was obtained in all samples extracted with Laemmli buffer alone and in combination with ultrasound. For immunochemical detection of soy proteins by enzyme-linked immunosorbent assay (ELISA), comparable detection was observed in extracts from all extraction conditions in all commercial samples with the exception of table cracker and veggie burger, where significantly higher detection was seen in extracts from Laemmli buffer only. For the dry mix and cookie samples, the degree of soy protein detection with ELISA varied among the different extraction conditions, but overall, extraction with only Laemmli buffer showed higher detection. Laemmli buffer with conventional extraction and UAE may be better alternatives or additional extraction methods in soy allergen detection. Different food matrices performed differently (whether it was for the recovery of total proteins or detection by ELISA) under different extraction conditions. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Application of ultrasound for enhanced extraction of prebiotic oligosaccharides from selected fruits and vegetables.

PubMed

Jovanovic-Malinovska, Ruzica; Kuzmanova, Slobodanka; Winkelhausen, Eleonora

2015-01-01

Ultrasound assisted extraction (UAE) was used to extract oligosaccharides from selected fruits (blueberry, nectarine, raspberry, watermelon) and vegetables (garlic, Jerusalem artichoke, leek, scallion, spring garlic and white onion). The individual fractions of the oligosaccharides were analyzed: 1-kestose (GF2), nystose (GF3) and 1F-β-fructofuranosylnystose (GF4) from the fructo-oligosaccharides (FOS), and raffinose and stachyose from the raffinose family oligosaccharides (RFO). Extraction parameters including solvent concentration (35-85% v/v), extraction temperature (25-50°C) and sonication time (5-15min) were examined using response surface methodology (RSM). Ethanol concentration of 63% v/v, temperature of 40°C and extraction time of 10min gave maximal concentration of the extracted oligosaccharides. The experimental values under optimal conditions were consistent with the predicted values. UAE increased the concentration of extracted oligosaccharides in all fruits and vegetables from 2 to 4-fold compared to conventional extraction. The highest increase of total oligosaccharides extracted by UAE was detected in Jerusalem artichoke, 7.17±0.348g/100gFW, compared to 1.62±0.094g/100gFW with conventional method. Copyright © 2014 Elsevier B.V. All rights reserved.

21 CFR 173.280 - Solvent extraction process for citric acid.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Solvent extraction process for citric acid. 173... Solvent extraction process for citric acid. A solvent extraction process for recovery of citric acid from conventional Aspergillus niger fermentation liquor may be safely used to produce food-grade citric acid in...

21 CFR 173.280 - Solvent extraction process for citric acid.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Solvent extraction process for citric acid. 173... Solvent extraction process for citric acid. A solvent extraction process for recovery of citric acid from conventional Aspergillus niger fermentation liquor may be safely used to produce food-grade citric acid in...

21 CFR 173.280 - Solvent extraction process for citric acid.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Solvent extraction process for citric acid. 173... Solvent extraction process for citric acid. A solvent extraction process for recovery of citric acid from conventional Aspergillus niger fermentation liquor may be safely used to produce food-grade citric acid in...

21 CFR 173.280 - Solvent extraction process for citric acid.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Solvent extraction process for citric acid. 173.280... extraction process for citric acid. A solvent extraction process for recovery of citric acid from conventional Aspergillus niger fermentation liquor may be safely used to produce food-grade citric acid in...

Competitive region orientation code for palmprint verification and identification

NASA Astrophysics Data System (ADS)

Tang, Wenliang

2015-11-01

Orientation features of the palmprint have been widely investigated in coding-based palmprint-recognition methods. Conventional orientation-based coding methods usually used discrete filters to extract the orientation feature of palmprint. However, in real operations, the orientations of the filter usually are not consistent with the lines of the palmprint. We thus propose a competitive region orientation-based coding method. Furthermore, an effective weighted balance scheme is proposed to improve the accuracy of the extracted region orientation. Compared with conventional methods, the region orientation of the palmprint extracted using the proposed method can precisely and robustly describe the orientation feature of the palmprint. Extensive experiments on the baseline PolyU and multispectral palmprint databases are performed and the results show that the proposed method achieves a promising performance in comparison to conventional state-of-the-art orientation-based coding methods in both palmprint verification and identification.

A Procedure for the supercritical fluid extraction of coal samples, with subsequent analysis of extracted hydrocarbons

USGS Publications Warehouse

Kolak, Jonathan J.

2006-01-01

Introduction: This report provides a detailed, step-by-step procedure for conducting extractions with supercritical carbon dioxide (CO2) using the ISCO SFX220 supercritical fluid extraction system. Protocols for the subsequent separation and analysis of extracted hydrocarbons are also included in this report. These procedures were developed under the auspices of the project 'Assessment of Geologic Reservoirs for Carbon Dioxide Sequestration' (see http://pubs.usgs.gov/fs/fs026-03/fs026-03.pdf) to investigate possible environmental ramifications associated with CO2 storage (sequestration) in geologic reservoirs, such as deep (~1 km below land surface) coal beds. Supercritical CO2 has been used previously to extract contaminants from geologic matrices. Pressure-temperature conditions within deep coal beds may render CO2 supercritical. In this context, the ability of supercritical CO2 to extract contaminants from geologic materials may serve to mobilize noxious compounds from coal, possibly complicating storage efforts. There currently exists little information on the physicochemical interactions between supercritical CO2 and coal in this setting. The procedures described herein were developed to improve the understanding of these interactions and provide insight into the fate of CO2 and contaminants during simulated CO2 injections.

[Learning curve of vacuum extraction in residency: a preliminary study].

PubMed

Velemir, L; Vendittelli, F; Bonnefoy, C; Accoceberry, M; Savary, D; Gallot, D

2009-09-01

The aim of this study was to assess the lurning curve of young residents for vacuum extraction. All vacuum extractions performed in our department by five residents (< or =5th semester) during a study period of nine months were systematically supervised by a senior who fulfilled an assessment questionnaire from which was calculated a score reflecting the quality of the extraction. Fifty-four vacuum extractions were assessed with a mean of 10.8+/-2.9 (range, 10-13) procedures by resident. We compared the group including the six first procedures performed by each resident (group 1, n = 30) with the group including the following procedures (group 2, n = 24). We observed in the group 2 compared to the group 1, a significant improvement of the scores mean (12.3+/-5.4 vs 8.4+/-6.2, p = 0.016) and a significant reduction of the need for manual assistance by the senior (12.5% vs 40%, p = 0.034). We report a method for the learning and assessment of vacuum extraction feasible at "the bed" of the patient. This approach allows to observe a significant progression of the resident for the technique of vacuum extraction on a dozen of procedures.

Rapid and simultaneous detection of Mycobacterium tuberculosis complex and Beijing/W genotype in sputum by an optimized DNA extraction protocol and a novel multiplex real-time PCR.

PubMed

Leung, Eric T Y; Zheng, L; Wong, Rity Y K; Chan, Edward W C; Au, T K; Chan, Raphael C Y; Lui, Grace; Lee, Nelson; Ip, Margaret

2011-07-01

Rapid diagnosis and genotyping of Mycobacterium tuberculosis by molecular methods are often limited by the amount and purity of DNA extracted from body fluids. In this study, we evaluated 12 DNA extraction methods and developed a highly sensitive protocol for mycobacterial DNA extraction directly from sputa using surface-coated magnetic particles. We have also developed a novel multiplex real-time PCR for simultaneous identification of M. tuberculosis complex and the Beijing/W genotype (a hypervirulent sublineage of M. tuberculosis) by using multiple fluorogenic probes targeting both the M. tuberculosis IS6110 and the Rv0927c-pstS3 intergenic region. With reference strains and clinical isolates, our real-time PCR accurately identified 20 non-Beijing/W and 20 Beijing/W M. tuberculosis strains from 17 different species of nontuberculosis Mycobacterium (NTM). Further assessment of our DNA extraction protocol and real-time PCR with 335 nonduplicate sputum specimens correctly identified all 74 M. tuberculosis culture-positive specimens. In addition, 15 culture-negative specimens from patients with confirmed tuberculosis were also identified. No cross-reactivity was detected with NTM specimens (n = 31). The detection limit of the assay is 10 M. tuberculosis bacilli, as determined by endpoint dilution analysis. In conclusion, an optimized DNA extraction protocol coupled with a novel multiprobe multiplex real-time PCR for the direct detection of M. tuberculosis, including Beijing/W M. tuberculosis, was found to confer high sensitivity and specificity. The combined procedure has the potential to compensate for the drawbacks of conventional mycobacterial culture in routine clinical laboratory setting, such as the lengthy incubation period and the limitation to viable organisms.

Comparison of micellar extraction combined with ionic liquid based vortex-assisted liquid-liquid microextraction and modified quick, easy, cheap, effective, rugged, and safe method for the determination of difenoconazole in cowpea.

PubMed

Chen, Xiaochu; Bian, Yanli; Liu, Fengmao; Teng, Peipei; Sun, Pan

2017-10-06

Two simple sample pretreatment for the determination of difenoconazole in cowpea was developed including micellar extraction combined with ionic liquid based vortex-assisted liquid-liquid microextraction (ME-IL-VALLME) prior to high performance liquid chromatography (HPLC), and modified quick, easy, cheap, effective, rugged, and safe method (QuEChERS) coupled with HPLC-MS/MS. In ME-IL-VALLME method, the target analyte was extracted by surfactant Tween 20 micellar solution, then the supernatant was diluted with 3mL water to decrease the solubility of micellar solution. Subsequently, the vortex-assisted liquid-liquid microextraction (VALLME) procedure was performed in the diluted extraction solution by using the ionic liquid of 1-hexyl-3-methylimidazolium hexafluorophosphate ([HMIM]PF 6 ) as the extraction solvent and Tween 20 as an emulsifier to enhance the dispersion of the water-immiscible ionic liquid into the aqueous phase. Parameters that affect the extraction have been investigated in both methods Under the optimum conditions, the limits of quantitation were 0.10 and 0.05mgkg -1 , respectively. And good linearity was achieved with the correlation coefficient higher than 0.9941. The relative recoveries ranged from 78.6 to 94.8% and 92.0 to 118.0% with the relative standard deviations (RSD) of 7.9-9.6% and 1.2-3.2%, respectively. Both methods were quick, simple and inexpensive. However, the ME-IL-VALLME method provides higher enrichment factor compared with conventional QuEChERS method. The ME-IL-VALLME method has a strong potential for the determination of difenoconazole in complex vegetable matrices with HPLC. Copyright © 2017 Elsevier B.V. All rights reserved.

Quantitative determination of juvenile hormone III and 20-hydroxyecdysone in queen larvae and drone pupae of Apis mellifera by ultrasonic-assisted extraction and liquid chromatography with electrospray ionization tandem mass spectrometry.

PubMed

Zhou, Jinhui; Qi, Yitao; Hou, Yali; Zhao, Jing; Li, Yi; Xue, Xiaofeng; Wu, Liming; Zhang, Jinzhen; Chen, Fang

2011-09-01

In this paper, a method for the rapid and sensitive analysis of juvenile hormone III (JH III) and 20-hydroxyecdysone (20E) in queen larvae and drone pupae samples was presented. Ultrasound-assisted extraction provided a significant shortening of the leaching time for the extraction of JH III and 20E and satisfactory sensitivity as compared to the conventional shake extraction procedure. After extraction, determination was carried out by liquid chromatography-tandem mass spectrometry (LC-MS/MS) operating in electrospray ionization positive ion mode via multiple reaction monitoring (MRM) without any clean-up step prior to analysis. A linear gradient consisting of (A) water containing 0.1% formic acid and (B) acetonitrile containing 0.1% formic acid, and a ZORBAX SB-Aq column (100 mm × 2.1 mm, 3.5 μm) were employed to obtain the best resolution of the target analytes. The method was validated for linearity, limit of quantification, recovery, matrix effects, precision and stability. Drone pupae samples were found to contain 20E at concentrations of 18.0 ± 0.1 ng/g (mean ± SD) and JH III was detected at concentrations of 0.20 ± 0.06 ng/g (mean ± SD) in queen larvae samples. This validated method provided some practical information for the actual content of JH III and 20E in queen larvae and drone pupae samples. Copyright © 2011 Elsevier B.V. All rights reserved.

Soxhlet Extraction of Caffeine from Beverage Plants

NASA Astrophysics Data System (ADS)

Adam, D. J.; Mainwaring, J.; Quigley, Michael N.

1996-12-01

A simple procedure is described for the extraction of caffeine from coffee beans or granules, tea leaves, mat leaves, etc. Since dichloromethane and several other hazardous substances are used, the procedure is best performed in a fume hood. Following extraction, melting point determination of the crystalline precipitate establishes its positive identity. Includes 33 references.

SU-E-T-269: Differential Hazard Analysis For Conventional And New Linac Acceptance Testing Procedures

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

Harry, T; Yaddanapudi, S; Mutic, S

Purpose: New techniques and materials have recently been developed to expedite the conventional Linac Acceptance Testing Procedure (ATP). The new ATP method uses the Electronic Portal Imaging Device (EPID) for data collection and is presented separately. This new procedure is meant to be more efficient then conventional methods. While not clinically implemented yet, a prospective risk assessment is warranted for any new techniques. The purpose of this work is to investigate the risks and establish the pros and cons between the conventional approach and the new ATP method. Methods: ATP tests that were modified and performed with the EPID weremore » analyzed. Five domain experts (Medical Physicists) comprised the core analysis team. Ranking scales were adopted from previous publications related to TG 100. The number of failure pathways for each ATP test procedure were compared as well as the number of risk priority numbers (RPN’s) greater than 100 were compared. Results: There were fewer failure pathways with the new ATP compared to the conventional, 262 and 556, respectively. There were fewer RPN’s > 100 in the new ATP compared to the conventional, 41 and 115. Failure pathways and RPN’s > 100 for individual ATP tests on average were 2 and 3.5 times higher in the conventional ATP compared to the new, respectively. The pixel sensitivity map of the EPID was identified as a key hazard to the new ATP procedure with an RPN of 288 for verifying beam parameters. Conclusion: The significant decrease in failure pathways and RPN’s >100 for the new ATP mitigates the possibilities of a catastrophic error occurring. The Pixel Sensitivity Map determining the response and inherent characteristics of the EPID is crucial as all data and hence results are dependent on that process. Grant from Varian Medical Systems Inc.« less

Predicting the difficulty of a lead extraction procedure: the LED index.

PubMed

Bontempi, Luca; Vassanelli, Francesca; Cerini, Manuel; D'Aloia, Antonio; Vizzardi, Enrico; Gargaro, Alessio; Chiusso, Francesco; Mamedouv, Rashad; Lipari, Alessandro; Curnis, Antonio

2014-08-01

According to recent surveys, many sites performing permanent lead extractions do not meet the minimum prerequisites concerning personnel training, procedures' volume, or facility requirements. The current Heart Rhythm Society consensus on lead extractions suggests that patients should be referred to more experienced sites when a better outcome could be achieved. The purpose of this study was to develop a score aimed at predicting the difficulty of a lead extraction procedure through the analysis of a high-volume center database. This score could help to discriminate patients who should be sent to a referral site. A total of 889 permanent leads were extracted from 469 patients. All procedures were performed from January 2009 to May 2012 by two expert electrophysiologists, at the University Hospital of Brescia. Factors influencing the difficulty of a procedure were assessed using a univariate and a multivariate logistic regression model. The fluoroscopy time of the procedure was taken as an index of difficulty. A Lead Extraction Difficulty (LED) score was defined, considering the strongest predictors. Overall, 873 of 889 (98.2%) leads were completely removed. Major complications were reported in one patient (0.2%) who manifested cardiac tamponade. Minor complications occurred in six (1.3%) patients. No deaths occurred. Median fluoroscopic time was 8.7 min (3.3-17.3). A procedure was classified as difficult when fluoroscopy time was more than 31.2 min [90th percentile (PCTL)].At a univariate analysis, the number of extracted leads and years from implant were significantly associated with an increased risk of fluoroscopy time above 90th PCTL [odds ratio (OR) 1.51, 95% confidence interval (CI) 1.08-2.11, P = 0.01; and OR 1.19, 95% CI 1.12-1.25, P < 0.001, respectively). After adjusting for patient age and sex, and combining with other covariates potentially influencing the extraction procedure, a multivariate analysis confirmed a 71% increased risk of fluoroscopy time above 90th PCTL for each additional lead extracted (OR 1.71, 95% CI 1.06-2.77, P = 0.028) and a 23% increased risk for each year of lead age (OR 1.23, 95% CI 1.15-1.31, P < 0.001). Further nonindependent factors increasing the risk were the presence of active fixation leads and dual-coil implantable cardiac defibrillator leads. Conversely, vegetations significantly favored lead extraction.The LED score was defined as: number of extracted leads within a procedure + lead age (years from implant) + 1 if dual-coil - 1 if vegetation. The LED score independently predicted complex procedure (with fluoroscopic time >90th PCTL) both at univariate and multivariate analysis. A receiver-operating characteristic analysis showed an area under the curve of 0.81. A LED score greater than 10 could predict fluoroscopy time above 90th PCTL with a sensitivity of 78.3% and a specificity of 76.7%. The LED score is easy to compute and potentially predicts fluoroscopy time above 90th PCTL with a relatively high accuracy.

Signal-to-noise ratio application to seismic marker analysis and fracture detection

NASA Astrophysics Data System (ADS)

Xu, Hui-Qun; Gui, Zhi-Xian

2014-03-01

Seismic data with high signal-to-noise ratios (SNRs) are useful in reservoir exploration. To obtain high SNR seismic data, significant effort is required to achieve noise attenuation in seismic data processing, which is costly in materials, and human and financial resources. We introduce a method for improving the SNR of seismic data. The SNR is calculated by using the frequency domain method. Furthermore, we optimize and discuss the critical parameters and calculation procedure. We applied the proposed method on real data and found that the SNR is high in the seismic marker and low in the fracture zone. Consequently, this can be used to extract detailed information about fracture zones that are inferred by structural analysis but not observed in conventional seismic data.

Laboratory exercises, remote sensing of the environment

NASA Technical Reports Server (NTRS)

Mintzer, O.; Ray, J.

1981-01-01

The exercises are designed to convey principles and theory of remote sensing, and methodologies of its application to civil engineering and environmental concerns, including agronomy, geography, geology, wildlife, forestry, hydrology, and other related fields. During the exercises the student is introduced to several types of remote sensing represented by imagery from conventional format: panchromatic, black-and-white infrared, color, and infrared, 35mm aerial photography, thermal infrared, radar, multispectral scanner, and LANDSAT. Upon completion of the exercises the student is expected to know: (1) the electromagnetic spectrum, its various wavelength sub-sections and their uses as sensors, (2) the limitations of each sensor, (3) the interpretation techniques used for extracting data from the various types of imagery, and (4) the cost effectiveness of remote sensing procedures for acquiring and evaluating data of the natural environment.

A three-image algorithm for hard x-ray grating interferometry.

PubMed

Pelliccia, Daniele; Rigon, Luigi; Arfelli, Fulvia; Menk, Ralf-Hendrik; Bukreeva, Inna; Cedola, Alessia

2013-08-12

A three-image method to extract absorption, refraction and scattering information for hard x-ray grating interferometry is presented. The method comprises a post-processing approach alternative to the conventional phase stepping procedure and is inspired by a similar three-image technique developed for analyzer-based x-ray imaging. Results obtained with this algorithm are quantitatively comparable with phase-stepping. This method can be further extended to samples with negligible scattering, where only two images are needed to separate absorption and refraction signal. Thanks to the limited number of images required, this technique is a viable route to bio-compatible imaging with x-ray grating interferometer. In addition our method elucidates and strengthens the formal and practical analogies between grating interferometry and the (non-interferometric) diffraction enhanced imaging technique.

METHOD FOR THE SUPERCRITICAL FLUID EXTRACTION OF SOILS/SEDIMENTS

EPA Science Inventory

Supercritical fluid extraction has been publicized as an extraction method which has several advantages over conventional methods, and it is expected to result in substantial cost and labor savings. This study was designed to evaluate the feasibility of using supercritical fluid ...

Study on the extraction, purification and quantification of jasmonic acid, abscisic acid and indole-3-acetic acid in plants.

PubMed

Zhang, Feng Juan; Jin, You Ju; Xu, Xing You; Lu, Rong Chun; Chen, Hua Jun

2008-01-01

Jasmonic acid (JA), abscisic acid (ABA) and indole-3-acetic acid (IAA) are important plant hormones. Plant hormones are difficult to analyse because they occur in small concentrations and other substances in the plant interfere with their detection. To develop a new, inexpensive procedure for the rapid extraction and purification of IAA, ABA and JA from various plant species. Samples were prepared by extraction of plant tissues with methanol and ethyl acetate. Then the extracts were further purified and enriched with C(18) cartridges. The final extracts were derivatised with diazomethane and then measured by GC-MS. The results of the new methodology were compared with those of the Creelman and Mullet procedure. Sequential elution of the assimilates from the C(18 )cartridges revealed that IAA and ABA eluted in 40% methanol, while JA subsequently eluted in 60% methanol. The new plant hormone extraction and purification procedure produced results that were comparable to those obtained with the Creelman and Mullet's procedure. This new procedure requires only 0.5 g leaf samples to quantify these compounds with high reliability and can simultaneously determine the concentrations of the three plant hormones. A simple, inexpensive method was developed for determining endogenous IAA, ABA and JA concentrations in plant tissue.

Ultrasonic-energy enhance the ionic liquid-based dual microextraction to preconcentrate the lead in ground and stored rain water samples as compared to conventional shaking method.

PubMed

Nizamani, Sooraj; Kazi, Tasneem G; Afridi, Hassan I

2018-01-01

An efficient preconcentration technique based on ultrasonic-assisted ionic liquid-based dual microextraction (UA-ILDµE) method has been developed to preconcentrate the lead (Pb +2 ) in ground and stored rain water. In the current proposed method, Pb +2 was complexed with a chelating agent (dithizone), whereas an ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) was used for extraction purpose. The ultrasonic irradiation and electrical shaking system were applied to enhance the dispersion and extraction of Pb +2 complex in aqueous samples. For second phase, dual microextraction (DµE phase), the enriched Pb +2 complex in ionic liquid, extracted back into the acidic aqueous solution and finally determined by flame atomic absorption spectrometry. Some major analytical parameters that influenced the extraction efficiency of developed method, such as pH, concentration of ligand, volume of ionic liquid and samples, time of shaking in thermostatic electrical shaker and ultrasonic bath, effect of back extracting HNO 3 volume, matrix effect, centrifugation time and rate were optimized. At the sample volume of 25mL, the calculated preconcentration factor was 62.2. The limit of detection of proposed procedure for Pb +2 ions was found to be 0.54μgL -1 . The validation of developed method was performed by the analysis of certified sample of water SRM 1643e and standard addition method in a real water sample. The extraction recovery of Pb +2 was enhanced≥2% with shaking time of 80s in ultrasonic bath as compared to used thermostatic electrical shaker, where for optimum recovery up to 10min was required. The developed procedure was successfully used for the enrichment of Pb +2 in ground and stored rain water (surface water) samples of an endemic region of Pakistan. The resulted data indicated that the ground water samples were highly contaminated with Pb +2 , while some of the surface water samples were also have higher values of Pb +2 than permissible limit of WHO. The concentration of Pb +2 in surface and ground water samples was found in the range of 17.5-24.5 and 25.6-99.1μgL - 1 respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

Necessity of purification during bacterial DNA extraction with environmental soils

PubMed Central

Choi, Jung-Hyun

2017-01-01

Complexity and heterogeneity of soil samples have often implied the inclusion of purification steps in conventional DNA extraction for polymerase chain reaction (PCR) assays. Unfortunately the purification steps are also time and labor intensive. Therefore the necessity of DNA purification was re-visited and investigated for a variety of environmental soil samples that contained various amounts of PCR inhibitors. Bead beating and centrifugation was used as the baseline (without purification) method for DNA extraction. Its performance was compared with that of conventional DNA extraction kit (with purification). The necessity criteria for DNA purification were established with environmental soil samples. Using lysis conditions at 3000 rpm for 3 minutes with 0.1 mm glass beads, centrifugation time of 10 minutes and 1:10 dilution ratio, the baseline method outperformed conventional DNA extraction on cell seeded sand samples. Further investigation with PCR inhibitors (i.e., humic acids, clay, and magnesium [Mg]) showed that sand samples containing less than 10 μg/g humic acids and 70% clay may not require purifications. Interestingly, the inhibition pattern of Mg ion was different from other inhibitors due to the complexation interaction of Mg ion with DNA fragments. It was concluded that DNA extraction method without purification is suitable for soil samples that have less than 10 μg/g of humic acids, less than 70% clay content and less than 0.01% Mg ion content. PMID:28793754

Changes in Corneal Deformation Parameters after Lenticule Creation and Extraction during Small Incision Lenticule Extraction (SMILE) Procedure

PubMed Central

Shen, Yang; Zhao, Jing; Yao, Peijun; Miao, Huamao; Niu, Lingling

2014-01-01

Purpose To investigate the effects of lenticule creation and subsequent corneal lenticule extraction on corneal deformation parameters during small incision lenticule extraction (SMILE) procedure. Materials and Methods In this prospective study, 18 eyes of 10 patients (27.90±7.11 years, −5.64±2.45 diopters) scheduled for SMILE procedure were enrolled. Changes in the corneal deformation parameters, including deformation amplitude (DA), applanation time(AT1 and AT2), applanation length(AL1 and AL2), corneal velocity(CV1 and CV2), peak distance(P.Dist.), radius and intraocular pressure values were measured preoperatively, immediately after lenticule creation and subsequent to corneal lenticule extraction in all eyes with the Corvis Scheimpflug Technology (Corvis ST, OCULUS, Wetzlar, Germany). Repeated measures analysis of variance (ANOVA) with bonferroni-adjusted post hoc comparisons was performed to investigate changes following each step of the procedure. Results All surgical procedures were uneventful. A significant difference was detected among the three time points (pre-operation, post-lenticule creation and post lenticule extraction) for AT1 (P<0.001), AT2 (P = 0.001), DA(P<0.001), and IOP(P = 0.002). Bonferroni-adjusted post hoc comparisons indicated that there was no significant change in AT1, AT2, DA, or IOP after lenticule creation (post hoc P>0.05), but there was a significant change in these parameters following subsequent corneal lenticule extraction (post hoc P<0.01), when compared to values obtained pre-operatively. The scheimpflug camera of the Corvis ST demonstrated the intralamellar small gas bubbles formed from the vaporisation of tissue after lenticule creation and a gray zone was observed between the cap and the residual stromal bed after lenticule extraction. Conclusions There is a significant change in corneal deformation parameters following SMILE procedure. The changes may be caused predominantly by stromal lenticule extraction, while lenticule creation with femtosecond laser may not have an obvious effect on corneal deformation properties. PMID:25121508

Changes in corneal deformation parameters after lenticule creation and extraction during small incision lenticule extraction (SMILE) procedure.

PubMed

Shen, Yang; Zhao, Jing; Yao, Peijun; Miao, Huamao; Niu, Lingling; Wang, Xiaoying; Zhou, Xingtao

2014-01-01

To investigate the effects of lenticule creation and subsequent corneal lenticule extraction on corneal deformation parameters during small incision lenticule extraction (SMILE) procedure. In this prospective study, 18 eyes of 10 patients (27.90 ± 7.11 years, -5.64 ± 2.45 diopters) scheduled for SMILE procedure were enrolled. Changes in the corneal deformation parameters, including deformation amplitude (DA), applanation time(AT1 and AT2), applanation length(AL1 and AL2), corneal velocity(CV1 and CV2), peak distance(P.Dist.), radius and intraocular pressure values were measured preoperatively, immediately after lenticule creation and subsequent to corneal lenticule extraction in all eyes with the Corvis Scheimpflug Technology (Corvis ST, OCULUS, Wetzlar, Germany). Repeated measures analysis of variance (ANOVA) with bonferroni-adjusted post hoc comparisons was performed to investigate changes following each step of the procedure. All surgical procedures were uneventful. A significant difference was detected among the three time points (pre-operation, post-lenticule creation and post lenticule extraction) for AT1 (P<0.001), AT2 (P = 0.001), DA(P<0.001), and IOP(P = 0.002). Bonferroni-adjusted post hoc comparisons indicated that there was no significant change in AT1, AT2, DA, or IOP after lenticule creation (post hoc P>0.05), but there was a significant change in these parameters following subsequent corneal lenticule extraction (post hoc P<0.01), when compared to values obtained pre-operatively. The scheimpflug camera of the Corvis ST demonstrated the intralamellar small gas bubbles formed from the vaporisation of tissue after lenticule creation and a gray zone was observed between the cap and the residual stromal bed after lenticule extraction. There is a significant change in corneal deformation parameters following SMILE procedure. The changes may be caused predominantly by stromal lenticule extraction, while lenticule creation with femtosecond laser may not have an obvious effect on corneal deformation properties.

Extracting Undimensional Chains from Multidimensional Datasets: A Graph Theory Approach.

ERIC Educational Resources Information Center

Yamomoto, Yoneo; Wise, Steven L.

An order-analysis procedure, which uses graph theory to extract efficiently nonredundant, unidimensional chains of items from multidimensional data sets and chain consistency as a criterion for chain membership is outlined in this paper. The procedure is intended as an alternative to the Reynolds (1976) procedure which is described as being…

A Review of Current Methods for Analysis of Mycotoxins in Herbal Medicines

PubMed Central

Zhang, Lei; Dou, Xiao-Wen; Zhang, Cheng; Logrieco, Antonio F.; Yang, Mei-Hua

2018-01-01

The presence of mycotoxins in herbal medicines is an established problem throughout the entire world. The sensitive and accurate analysis of mycotoxin in complicated matrices (e.g., herbs) typically involves challenging sample pretreatment procedures and an efficient detection instrument. However, although numerous reviews have been published regarding the occurrence of mycotoxins in herbal medicines, few of them provided a detailed summary of related analytical methods for mycotoxin determination. This review focuses on analytical techniques including sampling, extraction, cleanup, and detection for mycotoxin determination in herbal medicines established within the past ten years. Dedicated sections of this article address the significant developments in sample preparation, and highlight the importance of this procedure in the analytical technology. This review also summarizes conventional chromatographic techniques for mycotoxin qualification or quantitation, as well as recent studies regarding the development and application of screening assays such as enzyme-linked immunosorbent assays, lateral flow immunoassays, aptamer-based lateral flow assays, and cytometric bead arrays. The present work provides a good insight regarding the advanced research that has been done and closes with an indication of future demand for the emerging technologies. PMID:29393905

Radiochemical determination of 241Am and Pu(alpha) in environmental materials.

PubMed

Warwick, P E; Croudace, I W; Oh, J S

2001-07-15

Americium-241 and plutonium determinations will become of greater importance over the coming decades as 137Cs and 241Pu decay. The impact of 137Cs on environmental chronology has been great, but its potency is waning as it decays and diffuses. Having 241Am and Pu as unequivocal markers for the 1963 weapon fallout maximum is important for short time scale environmental work, but a fast and reliable procedure is required for their separation. The developed method described here begins by digesting samples using a lithium borate fusion although an aqua regia leachate is also effective in many instances. Isolation of the Am and Pu is then achieved using a combination of extraction chromatography and conventional anion exchange chromatography. The whole procedure has been optimized, validated, and assessed for safety. The straightforwardness of this technique permits the analysis of large numbers of samples and makes 241Am-based techniques for high-resolution sediment accumulation rate studies attractive. In addition, the technique can be employed for the sequential measurement of Pu and Am in environmental surveillance programs, potentially reducing analytical costs and turnround times.

Manufacturing Implant Supported Auricular Prostheses by Rapid Prototyping Techniques

PubMed Central

Karatas, Meltem Ozdemir; Cifter, Ebru Demet; Ozenen, Didem Ozdemir; Balik, Ali; Tuncer, Erman Bulent

2011-01-01

Maxillofacial prostheses are usually fabricated on the models obtained following the impression procedures. Disadvantages of conventional impression techniques used in production of facial prosthesis are deformation of soft tissues caused by impression material and disturbance of the patient due to. Additionally production of prosthesis by conventional methods takes longer time. Recently, rapid prototyping techniques have been developed for extraoral prosthesis in order to reduce these disadvantages of conventional methods. Rapid prototyping technique has the potential to simplify the procedure and decrease the laboratory work required. It eliminates the need for measurement impression procedures and preparation of wax model to be performed by prosthodontists themselves In the near future this technology will become a standard for fabricating maxillofacial prostheses. PMID:21912504

Transparent DNA/RNA Co-extraction Workflow Protocol Suitable for Inhibitor-Rich Environmental Samples That Focuses on Complete DNA Removal for Transcriptomic Analyses

PubMed Central

Lim, Natalie Y. N.; Roco, Constance A.; Frostegård, Åsa

2016-01-01

Adequate comparisons of DNA and cDNA libraries from complex environments require methods for co-extraction of DNA and RNA due to the inherent heterogeneity of such samples, or risk bias caused by variations in lysis and extraction efficiencies. Still, there are few methods and kits allowing simultaneous extraction of DNA and RNA from the same sample, and the existing ones generally require optimization. The proprietary nature of kit components, however, makes modifications of individual steps in the manufacturer’s recommended procedure difficult. Surprisingly, enzymatic treatments are often performed before purification procedures are complete, which we have identified here as a major problem when seeking efficient genomic DNA removal from RNA extracts. Here, we tested several DNA/RNA co-extraction commercial kits on inhibitor-rich soils, and compared them to a commonly used phenol-chloroform co-extraction method. Since none of the kits/methods co-extracted high-quality nucleic acid material, we optimized the extraction workflow by introducing small but important improvements. In particular, we illustrate the need for extensive purification prior to all enzymatic procedures, with special focus on the DNase digestion step in RNA extraction. These adjustments led to the removal of enzymatic inhibition in RNA extracts and made it possible to reduce genomic DNA to below detectable levels as determined by quantitative PCR. Notably, we confirmed that DNase digestion may not be uniform in replicate extraction reactions, thus the analysis of “representative samples” is insufficient. The modular nature of our workflow protocol allows optimization of individual steps. It also increases focus on additional purification procedures prior to enzymatic processes, in particular DNases, yielding genomic DNA-free RNA extracts suitable for metatranscriptomic analysis. PMID:27803690

Low-Budget Instrumentation of a Conventional Leg Press to Measure Reliable Isometric-Strength Capacity.

PubMed

Baur, Heiner; Groppa, Alessia Severina; Limacher, Regula; Radlinger, Lorenz

2016-02-02

Maximum strength and rate of force development (RFD) are 2 important strength characteristics for everyday tasks and athletic performance. Measurements of both parameters must be reliable. Expensive isokinetic devices with isometric modes are often used. The possibility of cost-effective measurements in a practical setting would facilitate quality control. The purpose of this study was to assess the reliability of measurements of maximum isometric strength (Fmax) and RFD on a conventional leg press. Sixteen subjects (23 ± 2 y, 1.68 ± 0.05 m, 59 ± 5 kg) were tested twice within 1 session. After warm-up, subjects performed 2 times 5 trials eliciting maximum voluntary isometric contractions on an instrumented leg press (1- and 2-legged randomized). Fmax (N) and RFD (N/s) were extracted from force-time curves. Reliability was determined for Fmax and RFD by calculating the intraclass correlation coefficient (ICC), the test-retest variability (TRV), and the bias and limits of agreement. Reliability measures revealed good to excellent ICCs of .80-.93. TRV showed mean differences between measurement sessions of 0.4-6.9%. The systematic error was low compared with the absolute mean values (Fmax 5-6%, RFD 1-4%). The implementation of a force transducer into a conventional leg press provides a viable procedure to assess Fmax and RFD. Both performance parameters can be assessed with good to excellent reliability allowing quality control of interventions.

Rapid identification of clinical mycobacterial isolates by protein profiling using matrix assisted laser desorption ionization-time of flight mass spectrometry.

PubMed

Panda, A; Kurapati, S; Samantaray, J C; Myneedu, V P; Verma, A; Srinivasan, A; Ahmad, H; Behera, D; Singh, U B

2013-01-01

The purpose of this study was to evaluate the identification of Mycobacterium tuberculosis which is often plagued with ambiguity. It is a time consuming process requiring 4-8 weeks after culture positivity, thereby delaying therapeutic intervention. For a successful treatment and disease management, timely diagnosis is imperative. We evaluated a rapid, proteomic based technique for identification of clinical mycobacterial isolates by protein profiling using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Freshly grown mycobacterial isolates were used. Acetonitrile/trifluoroacetic acid extraction procedure was carried out, following which cinnamic acid charged plates were subjected to identification by MALDI-TOF MS. A comparative analysis of 42 clinical mycobacterial isolates using the MALDI-TOF MS and conventional techniques was carried out. Among these, 97.61% were found to corroborate with the standard methods at genus level and 85.36% were accurate till the species level. One out of 42 was not in accord with the conventional assays because MALDI-TOF MS established it as Mycobacterium tuberculosis (log (score)>2.0) and conventional methods established it to be non-tuberculous Mycobacterium. MALDI-TOF MS was found to be an accurate, rapid, cost effective and robust system for identification of mycobacterial species. This innovative approach holds promise for early therapeutic intervention leading to better patient care.

Rapid methods for extraction and concentration of poliovirus from oyster tissues.

PubMed

Richards, G P; Goldmintz, D; Green, D L; Babinchak, J A

1982-12-01

A procedure is discussed for the extraction of poliovirus from oyster meats by modification of several enterovirus extraction techniques. The modified method uses meat extract and Cat-Floc, a polycationic electrolyte, for virus extraction and concentration. Virus recovery from inoculated oyster homogenates is 93-120%. Adsorption of viruses to oyster proteins by acidification of homogenates does not affect virus recovery. Elution of viruses from oyster proteins appears more efficient at pH 9.5 than at pH 8.0. This technique is relatively simple, economical and requires only 2.5 h to complete the combined extraction and concentration procedure.

Stormwater Characterization and Lagoon Sediment Analysis, Grand Forks Air Force Base, North Dakota

DTIC Science & Technology

1990-08-01

tetrachloroethylene, and 0.0026 mg/l ethyl benzene. Analyses showed no pesticides . 4. Extraction Procedure (EP) Analysis. An AFOEHL contractor performed EP extraction ...runoff met North Dakota state stream standards. Lagoon sediment did not contain Extraction Procedure hazardous chemicals. Stormwater runoff exceeded...Standards for Water Quality for the State of North Dakota ( Extracts ) 39 D Site/Analysis Summary 69 E Lift Station Flow Records 73 F Wastewater

Identification of polar, ionic, and highly water soluble organic pollutants in untreated industrial wastewaters

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

Castillo, M.; Alonso, M.C.; Riu, J.

1999-04-15

This paper presents a generic protocol for the determination of polar, ionic, and highly water soluble organic pollutants on untreated industrial wastewaters involving the use of two different solid-phase extraction (SPE) methodologies followed by liquid chromatography-mass spectrometry (LC-MS). Untreated industrial wastewaters might contain natural and synthetic dissolved organic compounds with total organic carbon (TOC) values varying between 100 and 3000 mg/L. All polar, ionic and highly water soluble compounds comprising more than 95% of the organic content and with major contribution to the total toxicity of the sample cannot be analyzed by conventional gas chromatography-mass spectrometry (GC-MS), and LC-MS ismore » a good alternative. In this work two extraction procedures were used to obtain fractionated extracts of the nonionic polar compounds: a polymeric Isolute ENV + SPE cartridge for the preconcentration of anionic analytes and a sequential solid-phase extraction (SSPE) method percolating the samples first in octadecylsilica cartridge in series with the polymeric Lichrolut EN cartridge. Average recoveries ranging from 72% to 103% were obtained for a variety of 23 different analytes. Determination of nonionic pollutants was accomplished by reverse-phase liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS), while anionic compounds were analyzed by ion pair chromatography-electrospray-mass spectrometry (IP-ESI-MS) and LC-ESI-MS. This protocol was applied to a pilot survey of textile and tannery wastewaters leading to the identification and quantification of 33 organic pollutants.« less

Modified procedure to determine acid-insoluble lignin in wood and pulp

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

Effland, M.J.

1977-10-01

If wood is treated with strong acid, carbohydrates are hydrolyzed and solubilized. The insoluble residue is by definition lignin and can be measured gravimetrically. The standard method of analysis requires samples of 1 or 2 g of wood or pulp. In research at this laboratory these amounts of sample are often not available for analytical determinations. Thus we developed a modification of the standard procedure suitable for much smaller sample amounts. The modification is based on the procedure of Saeman. Wood samples require extraction prior to lignin analysis to remove acid-insoluble extractives that will be measured as lignin. Usually thismore » involves only a standard extraction with ethanol--benzene. However, woods high in tannin must also be subjected to extraction with alcohol. Pulps seldom require extraction.« less

Preoperative short hookwire placement for small pulmonary lesions: evaluation of technical success and risk factors for initial placement failure.

PubMed

Iguchi, Toshihiro; Hiraki, Takao; Matsui, Yusuke; Fujiwara, Hiroyasu; Masaoka, Yoshihisa; Tanaka, Takashi; Sato, Takuya; Gobara, Hideo; Toyooka, Shinichi; Kanazawa, Susumu

2018-05-01

To retrospectively evaluate the technical success of computed tomography fluoroscopy-guided short hookwire placement before video-assisted thoracoscopic surgery and to identify the risk factors for initial placement failure. In total, 401 short hookwire placements for 401 lesions (mean diameter 9.3 mm) were reviewed. Technical success was defined as correct positioning of the hookwire. Possible risk factors for initial placement failure (i.e., requirement for placement of an additional hookwire or to abort the attempt) were evaluated using logistic regression analysis for all procedures, and for procedures performed via the conventional route separately. Of the 401 initial placements, 383 were successful and 18 failed. Short hookwires were finally placed for 399 of 401 lesions (99.5%). Univariate logistic regression analyses revealed that in all 401 procedures only the transfissural approach was a significant independent predictor of initial placement failure (odds ratio, OR, 15.326; 95% confidence interval, CI, 5.429-43.267; p < 0.001) and for the 374 procedures performed via the conventional route only lesion size was a significant independent predictor of failure (OR 0.793, 95% CI 0.631-0.996; p = 0.046). The technical success of preoperative short hookwire placement was extremely high. The transfissural approach was a predictor initial placement failure for all procedures and small lesion size was a predictor of initial placement failure for procedures performed via the conventional route. • Technical success of preoperative short hookwire placement was extremely high. • The transfissural approach was a significant independent predictor of initial placement failure for all procedures. • Small lesion size was a significant independent predictor of initial placement failure for procedures performed via the conventional route.

Piezosurgery or conventional rotatory instruments for inferior third molar extractions?

PubMed

Piersanti, Luigi; Dilorenzo, Matteo; Monaco, Giuseppe; Marchetti, Claudio

2014-09-01

The purpose of this study was to compare the discomfort and surgical outcomes of a piezosurgery device with those of rotatory instruments in lower third molar extraction. A split-mouth, randomized, unblinded clinical study was designed; the 2 molars had to have the same extraction difficulty score. The test side was extracted using a piezosurgery technique and the control side was extracted using a conventional handpiece. The primary endpoint was patient discomfort evaluated with the Postoperative Symptom Severity (PoSSe) scale, which was administered to each patient; secondary endpoints were pain, trismus, swelling, and surgical time evaluation. Paired-samples t test and repeated-measures analysis of variance were used to compare outcomes within patients. Ten consecutive patients (6 female, 4 male; mean age, 22.4 ± 2.3 yr) were recruited. The total score on the PoSSe scale was significantly lower for piezosurgery compared with the conventional rotating handpiece (24.7 ± 10.3 vs 36.0 ± 7.6; t = -4.27; P = .002). Moreover, postoperative swelling 1 week after surgery was significantly lower for piezosurgery than for the conventional rotating handpiece (2.75 ± 0.23 vs 3.1 ± 0.39 cm; t = -2.63; P = .027). Piezosurgery was associated with less postoperative discomfort and yielded better results for swelling. Piezosurgery seems to be a good technique in daily surgical practice, especially if applied in the critical steps in which safety and respect for soft tissue, bone, and nerves are necessary. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

CTEPP STANDARD OPERATING PROCEDURE FOR EXTRACTING AND PREPARING DERMAL WIPE AND SURFACE WIPE SAMPLES FOR ANALYSIS OF POLAR ORGANIC POLLUTANTS (SOP-5.27)

EPA Science Inventory

The method for extracting and preparing a dermal or surface wipe sample for analysis of acidic persistent organic pollutants is summarized in this standard operating procedure. It covers the extraction and concentration of samples that are to be analyzed by gas chromatography/mas...

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.

Development of Mackintosh Probe Extractor

NASA Astrophysics Data System (ADS)

Rahman, Noor Khazanah A.; Kaamin, Masiri; Suwandi, Amir Khan; Sahat, Suhaila; Jahaya Kesot, Mohd

2016-11-01

Dynamic probing is a continuous soil investigation technique, which is one of the simplest soil penetration test. It basically consist of repeatedly driving a metal tipped probe into the ground using a drop weight of fixed mass and travel. Testing was carried out continuously from ground level to the final penetration depth. Once the soil investigation work done, it is difficult to pull out the probe rod from the ground, due to strong soil structure grip against probe cone and prevent the probe rod out from the ground. Thus, in this case, a tool named Extracting Probe was created to assist in the process of retracting the probe rod from the ground. In addition, Extracting Probe also can reduce the time to extract the probe rod from the ground compare with the conventional method. At the same time, it also can reduce manpower cost because only one worker involve to handle this tool compare with conventional method used two or more workers. From experiment that have been done we found that the time difference between conventional tools and extracting probe is significant, average time difference is 155 minutes. In addition the extracting probe can reduce manpower usage, and also labour cost for operating the tool. With all these advantages makes this tool has the potential to be marketed.

Enzymatic digestion improves testicular sperm retrieval in non-obstructive azoospermic patients

PubMed Central

Modarresi, Tahereh; Sabbaghian, Marjan; Shahverdi, Abdolhossein; Hosseinifar, Hani; Akhlaghi, Ali Asghar; Sadighi Gilani, Mohammad Ali

2013-01-01

Background: In patients with non-obstructive azoospermia (NOA), vital spermatozoa from the tissue is obtained from testes by enzymatic treatment besides the mechanical treatment. Objective: To increase the sperm recovery success of testicular sperm extraction (TESE), with enzymatic digestion if no sperm is obtained from testis tissue by mechanical method. Materials and Methods: Tissue samples were collected from 150 men who presented with clinical and laboratory data indicating NOA by means of TESE and micro dissection TESE methods. Initially, mature spermatozoa were examined for by mechanical extraction technique shredding the biopsy fractions. In cases whom no spermatozoa was observed after maximum 30 min of initial searching under the inverted microscope, the procedure was followed by enzymatic digestion using DNaseI and collagenase type IV. Surgery type, pathology, AZF, karyotype, hormones and testis size were compared in patients. Results: Of 150 cases with NOA, conventional mincing method extended with enzymatic treatment yielded successful sperm recovery in 13 (about 9%) patients. Comparison of parameters revealed that level of FSH and LH were significantly different (p=0.04 and 0.08 respectively) between two groups that response negative and positive to enzymatic digestion. Conclusion: The combination of conventional TESE and enzymatic digestion is an effective method to recover spermatozoa. The benefit of the mincing combined with enzyme to sperm retrieval for NOA firstly shorten the mechanical searching time, leading to minimizing further cellular damage as well as exposure to external conditions, and secondly reduce the number of cases with sperm recovery failures. Also, the serum level of FSH and LH are factors that influence the chance of sperm retrieval. PMID:24639777

Prospective randomized comparison of cold snare polypectomy and conventional polypectomy for small colorectal polyps.

PubMed

Ichise, Yasuyuki; Horiuchi, Akira; Nakayama, Yoshiko; Tanaka, Naoki

2011-01-01

The ideal method to remove small colorectal polyps is unknown. We compared removal by colon snare transection without electrocautery (cold snare polypectomy) with conventional electrocautery snare polypectomy (hot polypectomy) in terms of procedure duration, difficulty in retrieving polyps, bleeding, and post-polypectomy symptoms. Patients with colorectal polyps up to 8 mm in diameter were randomized to polypectomy by cold snare technique (cold group) or conventional polypectomy (conventional group). The principal outcome measures were abdominal symptoms within 2 weeks after polypectomy. Secondary outcome measures were the rates of retrieval of colorectal polyps and bleeding. Eighty patients were randomized: cold group, n = 40 (101 polyps) and conventional group, n = 40 (104 polyps). The patients' demographic characteristics and the number and size of polyps removed were similar between the two techniques. Procedure time was significantly shorter with cold polypectomy vs. conventional polypectomy (18 vs. 25 min, p < 0.0001). Complete polyp retrieval rates were identical [96% (97/101) vs. 96% (100/104)]. No bleeding requiring hemostasis occurred in either group. Abdominal symptoms shortly after polypectomy were more common with conventional polypectomy (i.e. 20%; 8/40) than with cold polypectomy (i.e. 2.5%; 1/40; p = 0.029). Cold polypectomy was superior to conventional polypectomy in terms of procedure time and post-polypectomy abdominal symptoms. The two methods were otherwise essentially identical in terms of bleeding risk and complete polyp retrieval. Cold polypectomy is therefore the preferred method for removal of small colorectal polyps. Copyright © 2011 S. Karger AG, Basel.

Analysis of simulated angiographic procedures. Part 2: extracting efficiency data from audio and video recordings.

PubMed

Duncan, James R; Kline, Benjamin; Glaiberman, Craig B

2007-04-01

To create and test methods of extracting efficiency data from recordings of simulated renal stent procedures. Task analysis was performed and used to design a standardized testing protocol. Five experienced angiographers then performed 16 renal stent simulations using the Simbionix AngioMentor angiographic simulator. Audio and video recordings of these simulations were captured from multiple vantage points. The recordings were synchronized and compiled. A series of efficiency metrics (procedure time, contrast volume, and tool use) were then extracted from the recordings. The intraobserver and interobserver variability of these individual metrics was also assessed. The metrics were converted to costs and aggregated to determine the fixed and variable costs of a procedure segment or the entire procedure. Task analysis and pilot testing led to a standardized testing protocol suitable for performance assessment. Task analysis also identified seven checkpoints that divided the renal stent simulations into six segments. Efficiency metrics for these different segments were extracted from the recordings and showed excellent intra- and interobserver correlations. Analysis of the individual and aggregated efficiency metrics demonstrated large differences between segments as well as between different angiographers. These differences persisted when efficiency was expressed as either total or variable costs. Task analysis facilitated both protocol development and data analysis. Efficiency metrics were readily extracted from recordings of simulated procedures. Aggregating the metrics and dividing the procedure into segments revealed potential insights that could be easily overlooked because the simulator currently does not attempt to aggregate the metrics and only provides data derived from the entire procedure. The data indicate that analysis of simulated angiographic procedures will be a powerful method of assessing performance in interventional radiology.

Physician control of needle and syringe during aspiration-injection procedures with the new reciprocating syringe.

PubMed

Sibbitt, Wilmer; Sibbitt, Randy R; Michael, Adrian A; Fu, Druce I; Draeger, Hilda T; Twining, Jon M; Bankhurst, Arthur D

2006-04-01

To evaluate physician control of needle and syringe during aspiration-injection syringe procedures by comparing the new reciprocating procedure syringe to a traditional conventional syringe. Twenty-six physicians were tested for their individual ability to control the reciprocating and conventional syringes in typical aspiration-injection procedures using a novel quantitative needle-based displacement procedure model. Subsequently, the physicians performed 48 clinical aspiration-injection (arthrocentesis) procedures on 32 subjects randomized to the reciprocating or conventional syringes. Clinical outcomes included procedure time, patient pain, and operator satisfaction. Multivariate modeling methods were used to determine the experimental variables in the syringe control model most predictive of clinical outcome measures. In the model system, the reciprocating syringe significantly improved physician control of the syringe and needle, with a 66% reduction in unintended forward penetration (p < 0.001) and a 68% reduction in unintended retraction (p < 0.001). In clinical arthrocentesis, improvements were also noted: 30% reduction in procedure time (p < 0.03), 57% reduction in patient pain (p < 0.001), and a 79% increase in physician satisfaction (p < 0.001). The variables in the experimental system--unintended forward penetration, unintended retraction, and operator satisfaction--independently predicted the outcomes of procedure time, patient pain, and physician satisfaction in the clinical study (p < or = 0.001). The reciprocating syringe reduces procedure time and patient pain and improves operator satisfaction with the procedure syringe. The reciprocating syringe improves physician performance in both the validated quantitative needle-based displacement model and in real aspiration-injection syringe procedures, including arthrocentesis.

Ultrasound-assisted extraction of natural antioxidants from the flower of Limonium sinuatum: Optimization and comparison with conventional methods.

PubMed

Xu, Dong-Ping; Zheng, Jie; Zhou, Yue; Li, Ya; Li, Sha; Li, Hua-Bin

2017-02-15

Natural antioxidants are widely used as dietary supplements or food additives. An optimized method of ultrasound-assisted extraction (UAE) was proposed for the effective extraction of antioxidants from the flowers of Limonium sinuatum and evaluated by response surface methodology. In this study, ethanol concentration, ratio of solvent to solid, ultrasonication time and temperature were investigated and optimized using a central composite rotatable design. The optimum extraction conditions were as follows: ethanol concentration, 60%; ratio of solvent to solid, 56.9:1mL/g; ultrasonication time, 9.8min; and temperature, 40°C. Under the optimal UAE conditions, the experimental values (483.01±15.39μmolTrolox/gDW) matched with those predicted (494.13μmolTrolox/gDW) within a 95% confidence level. In addition, the antioxidant activities of UAE were compared with those of conventional maceration and Soxhlet extraction methods, and the ultrasound-assisted extraction could give higher yield of antioxidants and markedly reduce the extraction time. Copyright © 2016 Elsevier Ltd. All rights reserved.

Standard Operating Procedure for the Grinding and Extraction of Lead in Paint using Nitric Acid and a Rotor/Stator System Powered by a High Speed Motor

EPA Science Inventory

This Standard Operating Procedure (SOP) describes a new, rapid, and relatively inexpensive one step procedure which grinds the paint samples removed from the substrate and simultaneously quantitatively extracts the Pb from the paint in only one step in preparation for quantitativ...

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF SOIL/HOUSE DUST FOR GC/MS ANALYSIS OF PESTICIDES (BCO-L-14.0)

EPA Science Inventory

The purpose of this SOP is to describe procedures for extracting and preparing dust or soil samples for gas chromatography/mass spectrometry (GC/MS) analysis of pesticides. This procedure was followed to ensure consistent data retrieval during the Arizona NHEXAS project and the "...

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF PESTICIDES FROM SURFACE WIPE SAMPLES (BCO-L-13.0)

EPA Science Inventory

The purpose of this SOP is to describe the procedures for extracting and preparing a sill surface wipe sample for gas chromatography/mass spectrometry (GC/MS) analysis of pesticides. This procedure is also used for the pre-shipment analysis of sill wipe samples for materials sui...

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF PESTICIDES FROM DERMAL WIPE SAMPLES (BCO-L-12.1)

EPA Science Inventory

The purpose of this SOP is to describe procedures for extracting and preparing a dermal wipe sample for GC/MS analysis of pesticides. This procedure was followed to ensure consistent data retrieval during the Arizona NHEXAS project and the "Border" study. Keywords: dermal wipe;...

Extraction, composition and functional properties of pennycress (Thlaspi arvense L.) press cake protein

USDA-ARS?s Scientific Manuscript database

This study compared two methods for extracting the protein in pennycress (Thlaspi arvense L.) press cake and determined the composition and functional properties of the protein products. Proteins in pennycress press cake were extracted by using the conventional alkali solubilization-acid precipitati...

Comparison of conventional and plant-extract disinfectant solutions on the hardness and color stability of a maxillofacial elastomer after artificial aging.

PubMed

Guiotti, Aimée Maria; Goiato, Marcelo Coelho; Dos Santos, Daniela Micheline; Vechiato-Filho, Aljomar José; Cunha, Bruno Guandalini; Paulini, Marcela Borghi; Moreno, Amália; de Almeida, Margarete Teresa Gottardo

2016-04-01

Silicone elastomers undergo physical and chemical degradation with disinfecting solutions. Phytotherapy may be a suitable solution for disinfection. However, its effect on the properties of the silicone material is unknown. The purpose of this in vitro study was to evaluate the effect of disinfection with conventional and plant-extract solutions and of artificial aging on the hardness and color stability of a facial silicone associated with pigments and an opacifier. Four hundred specimens of silicone (MDX4-4210) were fabricated (5×6 mm). Two pigment shades and 1 dry opacifier were combined in the tested material, and 4 groups (n=10) were obtained: colorless (GI), colorless with opacifier (GII), medium pigment with opacifier (GIII), and black pigment with opacifier (GIV). Specimens were subjected to disinfection (30 days) using saline solution, water, and neutral soap (digital friction, 30 seconds), chlorhexidine 4%, Hydrastis canadensis, and Cymbopogon nardus extracts (immersion, 10 minutes). Shore A hardness (ASTM D2240) and color analyses were performed before and after disinfection. Specimens were then exposed to 1008 hours of artificial aging (ASTM 53) and subjected to final hardness and color readings. The results were analyzed with ANOVA and the Tukey significant difference test (α=.05). The opacifier increased the hardness (GII). For GII, the H. canadensis solution and the friction with water and soap promoted significantly reduced hardness; the friction also promoted a reduction in this property for GIV. The GIII was not affected after disinfection. A significant difference was found between the ΔE values of the specimens disinfected with H. canadensis, C. nardus, and chlorhexidine, and specimens subjected to saline solution and neutral soap. The hardness of MDX4-4210 after the experimental procedure was considered clinically acceptable for facial prostheses. All groups showed clinically unacceptable color alterations regardless of the disinfecting solution. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Identification of lesion images from gastrointestinal endoscope based on feature extraction of combinational methods with and without learning process.

PubMed

Liu, Ding-Yun; Gan, Tao; Rao, Ni-Ni; Xing, Yao-Wen; Zheng, Jie; Li, Sang; Luo, Cheng-Si; Zhou, Zhong-Jun; Wan, Yong-Li

2016-08-01

The gastrointestinal endoscopy in this study refers to conventional gastroscopy and wireless capsule endoscopy (WCE). Both of these techniques produce a large number of images in each diagnosis. The lesion detection done by hand from the images above is time consuming and inaccurate. This study designed a new computer-aided method to detect lesion images. We initially designed an algorithm named joint diagonalisation principal component analysis (JDPCA), in which there are no approximation, iteration or inverting procedures. Thus, JDPCA has a low computational complexity and is suitable for dimension reduction of the gastrointestinal endoscopic images. Then, a novel image feature extraction method was established through combining the algorithm of machine learning based on JDPCA and conventional feature extraction algorithm without learning. Finally, a new computer-aided method is proposed to identify the gastrointestinal endoscopic images containing lesions. The clinical data of gastroscopic images and WCE images containing the lesions of early upper digestive tract cancer and small intestinal bleeding, which consist of 1330 images from 291 patients totally, were used to confirm the validation of the proposed method. The experimental results shows that, for the detection of early oesophageal cancer images, early gastric cancer images and small intestinal bleeding images, the mean values of accuracy of the proposed method were 90.75%, 90.75% and 94.34%, with the standard deviations (SDs) of 0.0426, 0.0334 and 0.0235, respectively. The areas under the curves (AUCs) were 0.9471, 0.9532 and 0.9776, with the SDs of 0.0296, 0.0285 and 0.0172, respectively. Compared with the traditional related methods, our method showed a better performance. It may therefore provide worthwhile guidance for improving the efficiency and accuracy of gastrointestinal disease diagnosis and is a good prospect for clinical application. Copyright © 2016 Elsevier B.V. All rights reserved.

Microwave assisted extraction, antioxidant potential and chromatographic studies of some Rasayana drugs.

PubMed

Mishra, Ashish; Mishra, Shilpi; Bhargav, Shilpi; Bhargava, Cs; Thakur, Mayank

2015-07-01

To study and compare the conventional extraction procedure with microwave assisted extraction (MAE) for some Ayurvedic Rasayana drugs and to evaluate their antioxidant potential and carry out the characterization of extracts by thin layer chromatography. Three Ayurvedic rasayana plants Allium sativum Linn., Bombax ceiba Linn. and Inula racemosa Hook. were evaluated for an improved MAE methodology by determining the effects of grinding degree, extraction solvent, effect of dielectric constant and duration of time on the extractive value. Antioxidant potential of all three drugs was evaluated with 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and reducing power was determined by using Gallic acid as standard. Further thin layer chromatographic (TLC) analysis was performed on pre-activated Silica Gel G plates and Rf value were compared with those reported for the important biomarkers. The total extractive value for Allium sativum Linn. was 36.95% (w/w) and 49.95% (w/w) for ethanol extraction respectively. In case of Bombax ceiba Linn. the yield of aqueous extract by MAE was 50% (w/w) compared to 42% (w/w) in ethanol (50% v/v). Percent yield of Inula racemosa Hook. in aqueous extract was found to be 27.55% (w/w) which was better than ethanol extract (50%) where the yield was 25.95% (w/w). Upon antioxidant activity evaluation. sativum extract showed an absorbance of 0.980±0.92 at concentration of 500 μg with maximum reducing capacity. This was followed by. ceiba Linn. 0.825±0.98 and. racemosa Hook. with 0.799±2.01 at a concentration of 500 μg. TLC based standardization of. sativum Linn. extract shows single spot with Rf value of 0.38, B. ceiba Linn. extract shows Rf values were 0.23, 0.58, 0.77, 0.92 and I. racemosa Hook. extract spot had a Rf value of 0.72. A significant improvement in extractive values was observed as a factor of time and other advantages by using MAE technology. All three drugs have high antioxidant potential and a TLC profiling similar to reported ones. The presence of fructan type polysaccharide can be further utilized for bioactivity directed fractionation and evaluation of immunomodulatory activity.

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.

Two-dimensional solid-phase extraction strategy for the selective enrichment of aminoglycosides in milk.

PubMed

Shen, Aijin; Wei, Jie; Yan, Jingyu; Jin, Gaowa; Ding, Junjie; Yang, Bingcheng; Guo, Zhimou; Zhang, Feifang; Liang, Xinmiao

2017-03-01

An orthogonal two-dimensional solid-phase extraction strategy was established for the selective enrichment of three aminoglycosides including spectinomycin, streptomycin, and dihydrostreptomycin in milk. A reversed-phase liquid chromatography material (C 18 ) and a weak cation-exchange material (TGA) were integrated in a single solid-phase extraction cartridge. The feasibility of two-dimensional clean-up procedure that experienced two-step adsorption, two-step rinsing, and two-step elution was systematically investigated. Based on the orthogonality of reversed-phase and weak cation-exchange procedures, the two-dimensional solid-phase extraction strategy could minimize the interference from the hydrophobic matrix existing in traditional reversed-phase solid-phase extraction. In addition, high ionic strength in the extracts could be effectively removed before the second dimension of weak cation-exchange solid-phase extraction. Combined with liquid chromatography and tandem mass spectrometry, the optimized procedure was validated according to the European Union Commission directive 2002/657/EC. A good performance was achieved in terms of linearity, recovery, precision, decision limit, and detection capability in milk. Finally, the optimized two-dimensional clean-up procedure incorporated with liquid chromatography and tandem mass spectrometry was successfully applied to the rapid monitoring of aminoglycoside residues in milk. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Determination of endocrine-disrupting compounds in water samples by magnetic nanoparticle-assisted dispersive liquid-liquid microextraction combined with gas chromatography-tandem mass spectrometry.

PubMed

Pérez, Rosa Ana; Albero, Beatriz; Tadeo, José Luis; Sánchez-Brunete, Consuelo

2016-11-01

A rapid extraction procedure is presented for the determination of five endocrine-disrupting compounds, estrone, ethinylestradiol, bisphenol A, triclosan, and 2-ethylhexylsalicylate, in water samples. The analysis involves a two-step extraction procedure that combines dispersive liquid-liquid microextraction (DLLME) with dispersive micro-solid phase extraction (D-μ-SPE), using magnetic nanoparticles, followed by in situ derivatization in the injection port of a gas chromatograph coupled to triple quadrupole mass spectrometry. The use of uncoated or oleate-coated Fe 3 O 4 nanoparticles as sorbent in the extraction process was evaluated and compared. The main parameters involved in the extraction process were optimized applying experimental designs. Uncoated Fe 3 O 4 nanoparticles were selected in order to simplify and make more cost-effective the procedure. DLLME was carried out at pH 3, during 2 min, followed by the addition of the nanoparticles for D-μ-SPE employing 1 min in the extraction. Analysis of spiked water samples of different sources gave satisfactory recovery results for all the compounds with detection limits ranging from 7 to 180 ng l -1 . Finally, the procedure was applied in tap, well, and river water. Graphical abstract Diagram of the extraction method using magnetic nanoparticles (MNPs).

Chemistry in the kitchen. Making ground meat more healthful.

PubMed

Small, D M; Oliva, C; Tercyak, A

1991-01-10

The National Cholesterol Education Program recommends a diet containing less than 30 percent of calories in the form of fat, less than 10 percent in the form of saturated fat, and less than 300 mg of cholesterol per day. Since Americans' diets generally exceed these recommendations, we wished to find an easy kitchen method to reduce substantially saturated fat and cholesterol in ground meat. Raw ground meat was heated in vegetable oil and rinsed with boiling water to extract fat and cholesterol. The fat-free broth was recombined with the meat to restore flavor. The amounts of total fat, saturated fat, and cholesterol in the meat after extraction were compared with the amounts in meat cooked as patties and in stir-fried, rinsed meat. When raw ground beef containing 9.6 to 20.8 percent fat was cooked as patties and the fat poured off, 6 to 17 percent of the fat and 1.3 to 4.3 percent of the cholesterol were lost. In stir-fried, rinsed ground beef, 23 to 59 percent of the fat and 9.0 to 18.8 percent of the cholesterol were lost. When vegetable oil was used to extract fat and cholesterol from beef containing 20.7 percent fat, a mean (+/- SD) of 67.7 +/- 1.6 percent of the fat and 39.2 +/- 5.1 percent of the cholesterol were lost. The differences between conventionally cooked meat and meat prepared by the extraction of fat were significant (P less than 0.001). An average of 43 percent (range, 38 to 49) of cholesterol was extracted from a wide variety of ground meats. Although conventional cooking produced no change in fatty-acid composition as compared with raw meat, our extraction process greatly increased the ratio of unsaturated to saturated fat, from 1.32 in conventionally cooked meat to 2.92 to 4.56 in meat after extraction. Extraction resulted in the loss of 72 to 87 percent of saturated fat. This method produces a tasty meat product that is much lower in saturated fat and cholesterol than conventionally cooked meat, and that can be used in sauces, soups, and solid meat products.

Non-conventional solvents in liquid phase microextraction and aqueous biphasic systems.

PubMed

An, Jiwoo; Trujillo-Rodríguez, María J; Pino, Verónica; Anderson, Jared L

2017-06-02

The development of rapid, convenient, and high throughput sample preparation approaches such as liquid phase microextraction techniques have been continuously developed over the last decade. More recently, significant attention has been given to the replacement of conventional organic solvents used in liquid phase microextraction techniques in order to reduce toxic waste and to improve selectivity and/or extraction efficiency. With these objectives, non-conventional solvents have been explored in liquid phase microextraction and aqueous biphasic systems. The utilized non-conventional solvents include ionic liquids, magnetic ionic liquids, and deep eutectic solvents. They have been widely used as extraction solvents or additives in various liquid phase microextraction modes including dispersive liquid-liquid microextraction, single-drop microextraction, hollow fiber-liquid phase microextraction, as well as in aqueous biphasic systems. This review provides an overview into the use of non-conventional solvents in these microextraction techniques in the past 5 years (2012-2016). Analytical applications of the techniques are also discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Novel biopsy forceps for diagnosis of biliary tract diseases during endoscopic retrograde cholangiopancreatography: a prospective comparative study with 90° adjustable and conventional biopsy forceps.

PubMed

Ishii, Kentaro; Itoi, Takao; Sofuni, Atsushi; Itokawa, Fumihide; Tsuchiya, Takayoshi; Kurihara, Toshio; Tsuji, Shujiro; Ikeuchi, Nobuhito; Umeda, Junko; Moriyasu, Fuminori

2012-01-01

Recently, controllable biopsy forceps (MTW, D°sseldorf, Germany) have been developed. This biopsy forceps were 90° adjustable. In the present study, the feasibility and efficacy of the controllable biopsy forceps were compared with those of conventional biopsy forceps in patients with biliary tract disease. A total of 27 patients with biliary tract lesions were enrolled. We evaluated the procedure time, the sample tissue size and the diagnostic accuracy. In addition, the physicians performing the procedure rated their impressions about operability into 3 classes: excellent, fair and poor. The sensitivity in distinguishing benign from malignant lesions was 71.4% (15/21) for the 90° adjustable type and 66.7% (14/21) for the conventional type. The accuracy rate was 77.8% (21/27) for the 90° adjustable type and 74.0% (20/27) for the conventional type. In terms of operability as rated by each physician, the 'excellent' rate was given more frequently to the 90° adjustable type 25.9% than for the conventional type 11.1% (p=0.047). This preliminary study showed that controllable biopsy forceps compared to conventional type biopsy forceps, despite a larger diameter, enables biopsy in a similar procedure time and its ease of use was rated better.

A new organic-rich soil reference material certified for its EDTA- and acetic acid- extractable contents of Cd, Cr, Cu, Ni, Pb and Zn, following collaboratively tested and harmonised procedures.

PubMed

Pueyo, M; Rauret, G; Bacon, J R; Gomez, A; Muntau, H; Quevauviller, P; López-Sánchez, J F

2001-02-01

There is an increasing requirement for assessment of the bioavailable metal fraction and the mobility of trace elements in soils upon disposal. One of the approaches is the use of leaching procedures, but the results obtained are operationally defined; therefore, their significance is highly dependent on the extraction protocol performed. So, for this type of study, there is a need for reference materials that allow the quality of measurements to be controlled. This paper describes the steps involved in the certification of an organic-rich soil reference material, BCR-700, for the EDTA- and acetic acid-extractable contents of some trace elements, following collaboratively tested and harmonised extraction procedures. Details are given for the preparation of the soil, homogeneity and stability testing, analytical procedures and the statistical selection of data to be included in the certification.

The Hague Convention on the Protection of Children and Cooperation in Respect of Intercountry Adoption.

ERIC Educational Resources Information Center

Duncan, William

1993-01-01

Reviews chapters of the Hague Convention on Intercountry Adoption which establish requirements for intercountry adoption, provide for a system of adoption authorities in contracting states, establish procedures to be adopted by the authorities, and provide for recognition of adoptions made under the convention. Notes that the convention guarantees…

A comparison of DNA extraction procedures for the detection of Mycobacterium ulcerans, the causative agent of Buruli ulcer, in clinical and environmental specimens.

PubMed

Durnez, Lies; Stragier, Pieter; Roebben, Karen; Ablordey, Anthony; Leirs, Herwig; Portaels, Françoise

2009-02-01

Mycobacterium ulcerans is the causative agent of Buruli ulcer, the third most common mycobacterial disease in humans after tuberculosis and leprosy. Although the disease is associated with aquatic ecosystems, cultivation of the bacillus from the environment is difficult to achieve. Therefore, at the moment, research is based on the detection by PCR of the insertion sequence IS2404 present in M. ulcerans and some closely related mycobacteria. In the present study, we compared four DNA extraction methods for detection of M. ulcerans DNA, namely the one tube cell lysis and DNA extraction procedure (OT), the FastPrep procedure (FP), the modified Boom procedure (MB), and the Maxwell 16 Procedure (M16). The methods were performed on serial dilutions of M. ulcerans, followed by PCR analysis with different PCR targets in M. ulcerans to determine the detection limit (DL) of each method. The purity of the extracted DNA and the time and effort needed were compared as well. All methods were performed on environmental specimens and the two best methods (MB and M16) were tested on clinical specimens for detection of M. ulcerans DNA. When comparing the DLs of the DNA extraction methods, the MB and M16 had a significantly lower DL than the OT and FP. For the different PCR targets, IS2404 showed a significantly lower DL than mlsA, MIRU1, MIRU5 and VNTR6. The FP and M16 were considerably faster than the MB and OT, while the purity of the DNA extracted with the MB was significantly higher than the DNA extracted with the other methods. The MB performed best on the environmental and clinical specimens. This comparative study shows that the modified Boom procedure, although lengthy, provides a better method of DNA extraction than the other methods tested for detection and identification of M. ulcerans in both clinical and environmental specimens.

Aerosols and Particulates Workshop Sampling Procedures and Venues Working Group Summary

NASA Technical Reports Server (NTRS)

Pachlhofer, Peter; Howard, Robert

1999-01-01

The Sampling Procedures and Venues Workgroup discussed the potential venues available and issues associated with obtaining measurements. Some of the issues included Incoming Air Quality, Sampling Locations, Probes and Sample Systems. The following is a summary of the discussion of the issues and venues. The influence of inlet air to the measurement of exhaust species, especially trace chemical species, must be considered. Analysis procedures for current engine exhaust emissions regulatory measurements require adjustments for air inlet humidity. As a matter of course in scientific investigations, it is recommended that "background" measurements for any species, particulate or chemical, be performed during inlet air flow before initiation of combustion, if possible, and during the engine test period as feasible and practical. For current regulatory measurements, this would be equivalent to setting the "zero" level for conventional gas analyzers. As a minimum, it is recommended that measurements of the humidity and particulates in the incoming air be taken at the start and end of each test run. Additional measurement points taken during the run are desirable if they can be practically obtained. It was felt that the presence of trace gases in the incoming air is not a significant problem. However, investigators should consider the ambient levels and influences of local air pollution for species of interest. Desired measurement locations depend upon the investigation requirements. A complete investigation of phenomenology of particulate formation and growth requires measurements at a number of locations both within the engine and in the exhaust field downstream of the nozzle exit plane. Desirable locations for both extractive and in situ measurements include: (1) Combustion Zone (Multiple axial locations); (2) Combustor Exit (Multiple radial locations for annular combustors); (3) Turbine Stage (Inlet and exit of the stage); (4) Exit Nozzle (Multiple axial locations downstream of the nozzle). Actual locations with potential for extractive or non-intrusive measurements depend upon the test article and test configuration. Committee members expressed the importance of making investigators aware of various ports that could allow access to various stages of the existing engines. Port locations are engine si)ecific and might allow extractive sampling or innovative hybrid optical-probe access. The turbine stage region was one the most desirable locations for obtaining samples and might be accessed through boroscope ports available in some engine designs. Discussions of probes and sampling systems quickly identified issues dependent on particular measurement quantities. With general consensus, the group recommends SAE procedures for measurements and data analyses of currently regulated exhaust species (CO2, CO, THC, NO(x),) using conventional gas sampling techniques. Special procedures following sound scientific practices must be developed as required for species and/or measurement conditions not covered by SAE standards. Several issues arose concerning short lived radicals and highly reactive species. For conventional sampling, there are concerns of perturbing the sample during extraction, line losses, line-wall reactions, and chemical reactions during the sample transport to the analyzers. Sample lines coated with quartz.or other materials should be investigated for minimization of such effects. The group advocates the development of innovative probe techniques and non-intrusive optical techniques for measurement of short lived radicals and highly reactive species that cannot be sampled accurately otherwise. Two innovative probe concepts were discussed. One concept uses specially designed probes to transfer optical beams to and from a region of flow inaccessible by traditional ports or windows. The probe can perturb the flow field but must have a negligible impact on the region to be optically sampled. Such probes are referred to as hybrid probes and are under development at AEDC for measurement in the high pressure, high temperature of a combustor under development for power generation. The other concept consists of coupling an instrument directly to the probe. The probe would isolate a representative sample stream, freeze chemical reactions and direct the sample into the analyzer portion of the probe. Thus, the measurement would be performed in situ without sample line losses due either to reactions or binding at the wall surfaces. This concept was used to develop a fast, in situ, time-of-flight mass spectrometer measurement system for temporal quantification of NO in the IMPULSE facility at AEDC. Additional work is required in this area to determine the best probe and sampling technique for each species measurement requirement identified by the Trace Chemistry Working Group. A partial list of Venues was used as a baseline for discussion. Additional venues were added to the list and the list was broken out into the following categories: (1)Engines (a) Sea Level Test Stands (b) Altitude Chambers; (2) Annular Combustor Test Stands, (3) Sector Flametube Test Stands, (4) Fundamentals Rigs/Experiments.

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

Determination of cadmium in sediments by diluted HCI extraction and isotope dilution ICP-MS.

PubMed

Terán-Baamonde, Javier; Soto-Ferreiro, Rosa-María; Carlosena, Alatzne; Andrade, José-Manuel; Prada, Darío

2018-08-15

Isotope dilution ICP-MS is proposed to measure the mass fraction of Cd extracted by diluted HCl in marine sediments, using a fast and simple extraction procedure based on ultrasonic probe agitation. The 111 Cd isotope was added before the extraction to achieve isotope equilibration with native Cd solubilized from the sample. The parameters affecting trueness and precision of isotope ratio measurements were evaluated carefully and subsequently corrected in order to minimize errors; they were: detector dead time, spectral interferences, mass discrimination factor and optimum sample/spike ratio. The mass fraction of Cd extracted was compared with the sum of the certified contents of the three steps of the sequential extraction procedure of the Standards, Measurements and Testing Programme (SM&T) analysing the BCR 701 sediment to validate the method. The certified and measured values agreed, giving a measured / certified mass fraction ratio of 1.05. Further, the extraction procedure itself was studied by adding the enriched isotope after the extraction step, which allowed verifying that analyte losses occurred during this process. Two additional reference sediments with certified total cadmium contents were also analysed. The method provided very good precision (0.9%, RSD) and a low detection limit, 1.8 ng g -1 . The procedural uncertainty budget was estimated following the EURACHEM Guide by means of the 'GUM Workbench' software, obtaining a relative expanded uncertainty of 1.5%. The procedure was applied to determine the bioaccessible mass fraction of Cd in sediments from two environmentally and economically important areas of Galicia (rias of Arousa and Vigo, NW of Spain). Copyright © 2018 Elsevier B.V. All rights reserved.

U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF PESTICIDES FROM DERMAL WIPE SAMPLES (BCO-L-12.1)

EPA Science Inventory

The purpose of this SOP is to describe procedures for extracting and preparing a dermal wipe sample for GC/MS analysis of pesticides. This procedure was followed to ensure consistent data retrieval during the Arizona NHEXAS project and the Border study. Keywords: dermal wipe; p...

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF SOIL AND HOUSE DUST SAMPLES FOR GC/MS ANALYSIS OF PESTICIDE AND PAH (BCO-L-28.0)

EPA Science Inventory

The purpose of this SOP is to describe procedures for extracting and preparing a dust or soil sample for gas chromatography mass spectrometry (GC/MS) analysis of pesticides and polyaromatic hydrocarbons (PAHs). This procedure was followed to ensure consistent data retrieval durin...

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF AIR SAMPLES FOR GC/MS ANALYSIS OF PESTICIDES (BCO-L-11.0)

EPA Science Inventory

The purpose of this SOP is to describe the procedures for extracting and preparing an air sample consisting of a polyurethane foam (PUF) plug and Teflon-coated glass fiber filter (Pallflex T60A20) for analysis of pesticides. This procedure covers sample preparation for samples t...

Nonredundant sparse feature extraction using autoencoders with receptive fields clustering.

PubMed

Ayinde, Babajide O; Zurada, Jacek M

2017-09-01

This paper proposes new techniques for data representation in the context of deep learning using agglomerative clustering. Existing autoencoder-based data representation techniques tend to produce a number of encoding and decoding receptive fields of layered autoencoders that are duplicative, thereby leading to extraction of similar features, thus resulting in filtering redundancy. We propose a way to address this problem and show that such redundancy can be eliminated. This yields smaller networks and produces unique receptive fields that extract distinct features. It is also shown that autoencoders with nonnegativity constraints on weights are capable of extracting fewer redundant features than conventional sparse autoencoders. The concept is illustrated using conventional sparse autoencoder and nonnegativity-constrained autoencoders with MNIST digits recognition, NORB normalized-uniform object data and Yale face dataset. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nicotine Levels and Presence of Selected Tobacco-Derived Toxins in Tobacco Flavoured Electronic Cigarette Refill Liquids

PubMed Central

Farsalinos, Konstantinos E.; Gillman, I. Gene; Melvin, Matt S.; Paolantonio, Amelia R.; Gardow, Wendy J.; Humphries, Kathy E.; Brown, Sherri E.; Poulas, Konstantinos; Voudris, Vassilis

2015-01-01

Background. Some electronic cigarette (EC) liquids of tobacco flavour contain extracts of cured tobacco leaves produced by a process of solvent extraction and steeping. These are commonly called Natural Extract of Tobacco (NET) liquids. The purpose of the study was to evaluate nicotine levels and the presence of tobacco-derived toxins in tobacco-flavoured conventional and NET liquids. Methods. Twenty-one samples (10 conventional and 11 NET liquids) were obtained from the US and Greek market. Nicotine levels were measured and compared with labelled values. The levels of tobacco-derived chemicals were compared with literature data on tobacco products. Results. Twelve samples had nicotine levels within 10% of the labelled value. Inconsistency ranged from −21% to 22.1%, with no difference observed between conventional and NET liquids. Tobacco-specific nitrosamines (TSNAs) were present in all samples at ng/mL levels. Nitrates were present almost exclusively in NET liquids. Acetaldehyde was present predominantly in conventional liquids while formaldehyde was detected in almost all EC liquids at trace levels. Phenols were present in trace amounts, mostly in NET liquids. Total TSNAs and nitrate, which are derived from the tobacco plant, were present at levels 200–300 times lower in 1 mL of NET liquids compared to 1 gram of tobacco products. Conclusions. NET liquids contained higher levels of phenols and nitrates, but lower levels of acetaldehyde compared to conventional EC liquids. The lower levels of tobacco-derived toxins found in NET liquids compared to tobacco products indicate that the extraction process used to make these products did not transfer a significant amount of toxins to the NET. Overall, all EC liquids contained far lower (by 2–3 orders of magnitude) levels of the tobacco-derived toxins compared to tobacco products. PMID:25811768

Nicotine levels and presence of selected tobacco-derived toxins in tobacco flavoured electronic cigarette refill liquids.

PubMed

Farsalinos, Konstantinos E; Gillman, I Gene; Melvin, Matt S; Paolantonio, Amelia R; Gardow, Wendy J; Humphries, Kathy E; Brown, Sherri E; Poulas, Konstantinos; Voudris, Vassilis

2015-03-24

Some electronic cigarette (EC) liquids of tobacco flavour contain extracts of cured tobacco leaves produced by a process of solvent extraction and steeping. These are commonly called Natural Extract of Tobacco (NET) liquids. The purpose of the study was to evaluate nicotine levels and the presence of tobacco-derived toxins in tobacco-flavoured conventional and NET liquids. Twenty-one samples (10 conventional and 11 NET liquids) were obtained from the US and Greek market. Nicotine levels were measured and compared with labelled values. The levels of tobacco-derived chemicals were compared with literature data on tobacco products. Twelve samples had nicotine levels within 10% of the labelled value. Inconsistency ranged from -21% to 22.1%, with no difference observed between conventional and NET liquids. Tobacco-specific nitrosamines (TSNAs) were present in all samples at ng/mL levels. Nitrates were present almost exclusively in NET liquids. Acetaldehyde was present predominantly in conventional liquids while formaldehyde was detected in almost all EC liquids at trace levels. Phenols were present in trace amounts, mostly in NET liquids. Total TSNAs and nitrate, which are derived from the tobacco plant, were present at levels 200-300 times lower in 1 mL of NET liquids compared to 1 gram of tobacco products. NET liquids contained higher levels of phenols and nitrates, but lower levels of acetaldehyde compared to conventional EC liquids. The lower levels of tobacco-derived toxins found in NET liquids compared to tobacco products indicate that the extraction process used to make these products did not transfer a significant amount of toxins to the NET. Overall, all EC liquids contained far lower (by 2-3 orders of magnitude) levels of the tobacco-derived toxins compared to tobacco products.

Cryopreservation of bull semen: Evolution from egg yolk based to soybean based extenders.

PubMed

Layek, S S; Mohanty, T K; Kumaresan, A; Parks, J E

2016-09-01

Since the inception of bovine semen cryopreservation, egg yolk and milk based extenders have been used to protect sperm from the detrimental effects of cooling and freezing. In recent years, demand for alternatives to conventional commercial extenders has arisen as the risk of introducing exotic diseases through transporting egg yolk based products has been recognized. Egg yolk can also interfere with sperm evaluation and the presence of particulate material in the extender may reduce fertility. Soybeans contain lecithin, a phospholipid fraction that can substitute for high molecular weight lipoprotein and phospholipids from egg yolk and prevent or ameliorate damage to the sperm plasma membrane that occurs during extension, cooling, and cryopreservation. Soy lecithin based extenders have been evaluated for processing and freezing bovine semen, although extender from soybean milk has not been studied as extensively. Commercially available soy lecithin based extenders are used increasingly but remain under scrutiny and are not universally accepted. With these observations in mind, this review is intended to examine effects of conventional cryopreservation procedures, methods of assessment, and potential for developing soybean extract as an acceptable alternative to traditional egg yolk and milk based extenders for bull sperm cryopreservation. Copyright © 2016. Published by Elsevier B.V.

Breast cancer detection in rotational thermography images using texture features

NASA Astrophysics Data System (ADS)

Francis, Sheeja V.; Sasikala, M.; Bhavani Bharathi, G.; Jaipurkar, Sandeep D.

2014-11-01

Breast cancer is a major cause of mortality in young women in the developing countries. Early diagnosis is the key to improve survival rate in cancer patients. Breast thermography is a diagnostic procedure that non-invasively images the infrared emissions from breast surface to aid in the early detection of breast cancer. Due to limitations in imaging protocol, abnormality detection by conventional breast thermography, is often a challenging task. Rotational thermography is a novel technique developed in order to overcome the limitations of conventional breast thermography. This paper evaluates this technique's potential for automatic detection of breast abnormality, from the perspective of cold challenge. Texture features are extracted in the spatial domain, from rotational thermogram series, prior to and post the application of cold challenge. These features are fed to a support vector machine for automatic classification of normal and malignant breasts, resulting in a classification accuracy of 83.3%. Feature reduction has been performed by principal component analysis. As a novel attempt, the ability of this technique to locate the abnormality has been studied. The results of the study indicate that rotational thermography holds great potential as a screening tool for breast cancer detection.

Quantum tomography for collider physics: illustrations with lepton-pair production

NASA Astrophysics Data System (ADS)

Martens, John C.; Ralston, John P.; Takaki, J. D. Tapia

2018-01-01

Quantum tomography is a method to experimentally extract all that is observable about a quantum mechanical system. We introduce quantum tomography to collider physics with the illustration of the angular distribution of lepton pairs. The tomographic method bypasses much of the field-theoretic formalism to concentrate on what can be observed with experimental data. We provide a practical, experimentally driven guide to model-independent analysis using density matrices at every step. Comparison with traditional methods of analyzing angular correlations of inclusive reactions finds many advantages in the tomographic method, which include manifest Lorentz covariance, direct incorporation of positivity constraints, exhaustively complete polarization information, and new invariants free from frame conventions. For example, experimental data can determine the entanglement entropy of the production process. We give reproducible numerical examples and provide a supplemental standalone computer code that implements the procedure. We also highlight a property of complex positivity that guarantees in a least-squares type fit that a local minimum of a χ 2 statistic will be a global minimum: There are no isolated local minima. This property with an automated implementation of positivity promises to mitigate issues relating to multiple minima and convention dependence that have been problematic in previous work on angular distributions.

Multifrequency synthesis and extraction using square wave projection patterns for quantitative tissue imaging.

PubMed

Nadeau, Kyle P; Rice, Tyler B; Durkin, Anthony J; Tromberg, Bruce J

2015-11-01

We present a method for spatial frequency domain data acquisition utilizing a multifrequency synthesis and extraction (MSE) method and binary square wave projection patterns. By illuminating a sample with square wave patterns, multiple spatial frequency components are simultaneously attenuated and can be extracted to determine optical property and depth information. Additionally, binary patterns are projected faster than sinusoids typically used in spatial frequency domain imaging (SFDI), allowing for short (millisecond or less) camera exposure times, and data acquisition speeds an order of magnitude or more greater than conventional SFDI. In cases where sensitivity to superficial layers or scattering is important, the fundamental component from higher frequency square wave patterns can be used. When probing deeper layers, the fundamental and harmonic components from lower frequency square wave patterns can be used. We compared optical property and depth penetration results extracted using square waves to those obtained using sinusoidal patterns on an in vivo human forearm and absorbing tube phantom, respectively. Absorption and reduced scattering coefficient values agree with conventional SFDI to within 1% using both high frequency (fundamental) and low frequency (fundamental and harmonic) spatial frequencies. Depth penetration reflectance values also agree to within 1% of conventional SFDI.

Multifrequency synthesis and extraction using square wave projection patterns for quantitative tissue imaging

PubMed Central

Nadeau, Kyle P.; Rice, Tyler B.; Durkin, Anthony J.; Tromberg, Bruce J.

2015-01-01

Abstract. We present a method for spatial frequency domain data acquisition utilizing a multifrequency synthesis and extraction (MSE) method and binary square wave projection patterns. By illuminating a sample with square wave patterns, multiple spatial frequency components are simultaneously attenuated and can be extracted to determine optical property and depth information. Additionally, binary patterns are projected faster than sinusoids typically used in spatial frequency domain imaging (SFDI), allowing for short (millisecond or less) camera exposure times, and data acquisition speeds an order of magnitude or more greater than conventional SFDI. In cases where sensitivity to superficial layers or scattering is important, the fundamental component from higher frequency square wave patterns can be used. When probing deeper layers, the fundamental and harmonic components from lower frequency square wave patterns can be used. We compared optical property and depth penetration results extracted using square waves to those obtained using sinusoidal patterns on an in vivo human forearm and absorbing tube phantom, respectively. Absorption and reduced scattering coefficient values agree with conventional SFDI to within 1% using both high frequency (fundamental) and low frequency (fundamental and harmonic) spatial frequencies. Depth penetration reflectance values also agree to within 1% of conventional SFDI. PMID:26524682

Procedure optimization for green synthesis of silver nanoparticles by aqueous extract of Eucalyptus oleosa.

PubMed

Pourmortazavi, Seied Mahdi; Taghdiri, Mehdi; Makari, Vajihe; Rahimi-Nasrabadi, Mehdi

2015-02-05

The present study is dealing with the green synthesis of silver nanoparticles using the aqueous extract of Eucalyptus oleosa as a green synthesis procedure without any catalyst, template or surfactant. Colloidal silver nanoparticles were synthesized by reacting aqueous AgNO3 with E. oleosa leaf extract at non-photomediated conditions. The significance of some synthesis conditions such as: silver nitrate concentration, concentration of the plant extract, time of synthesis reaction and temperature of plant extraction procedure on the particle size of synthesized silver particles was investigated and optimized. The participations of the studied factors in controlling the particle size of reduced silver were quantitatively evaluated via analysis of variance (ANOVA). The results of this investigation showed that silver nanoparticles could be synthesized by tuning significant parameters, while performing the synthesis procedure at optimum conditions leads to form silver nanoparticles with 21nm as averaged size. Ultraviolet-visible spectroscopy was used to monitor the development of silver nanoparticles formation. Meanwhile, produced silver nanoparticles were characterized by scanning electron microscopy, energy-dispersive X-ray, and FT-IR techniques. Copyright © 2014 Elsevier B.V. All rights reserved.

A Microcontroller Operated Device for the Generation of Liquid Extracts from Conventional Cigarette Smoke and Electronic Cigarette Aerosol.

PubMed

Anderson, Chastain A; Bokota, Rachael E; Majeste, Andrew E; Murfee, Walter L; Wang, Shusheng

2018-01-18

Electronic cigarettes are the most popular tobacco product among middle and high schoolers and are the most popular alternative tobacco product among adults. High quality, reproducible research on the consequences of electronic cigarette use is essential for understanding emerging public health concerns and crafting evidence based regulatory policy. While a growing number of papers discuss electronic cigarettes, there is little consistency in methods across groups and very little consensus on results. Here, we describe a programmable laboratory device that can be used to create extracts of conventional cigarette smoke and electronic cigarette aerosol. This protocol details instructions for the assembly and operation of said device, and demonstrates the use of the generated extract in two sample applications: an in vitro cell viability assay and gas-chromatography mass-spectrometry. This method provides a tool for making direct comparisons between conventional cigarettes and electronic cigarettes, and is an accessible entry point into electronic cigarette research.

Lenticuloschisis: A "No Dissection" Technique for Lenticule Extraction in Small Incision Lenticule Extraction.

PubMed

Ganesh, Sri; Brar, Sheetal

2017-08-01

To describe a "no dissection" technique of lenticule removal in small incision lenticule extraction (SMILE). After docking and laser delivery, a microforceps is used to grasp and gently peel off the lenticule from the underlying stromal bed, without performing any dissection of the upper and lower planes of the lenticule. Prerequisites are a surgeon experienced in the conventional SMILE technique, optimized laser energy settings, and a minimum peripheral lenticule thickness of 25 to 30 µm. The interface as assessed in postoperative dilated clinical photographs was seen to be clearer with less roughness compared to the conventional dissection technique. This may potentially result in better first postoperative visual acuity and quality of vision due to less corneal tissue trauma and minimal tissue handling, thus potentially resulting in faster visual recovery. No dissection lenticule removal is a feasible and reproducible technique that may result in better immediate visual quality compared to the conventional SMILE technique. [J Refract Surg. 2017;33(8):563-566.]. Copyright 2017, SLACK Incorporated.

Conventional oil and gas development alters forest songbird communities

Treesearch

Emily H. Thomas; Margaret C. Brittingham; Scott H. Stoleson

2014-01-01

Energy extraction within forest habitat is increasing at a rapid rate throughout eastern North America from the combined presence of conventional oil and gas, shale gas, and wind energy. We examined the effects of conventional oil and gas development on forest habitat including amounts of core and edge forest, the abundance of songbird species and guilds, species...

Development of a standardized sequential extraction protocol for simultaneous extraction of multiple actinide elements

DOE PAGES

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

2017-02-07

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.

On the problem of nonsense correlations in allergological tests after routine extraction.

PubMed

Rijckaert, G

1981-01-01

The influence of extraction procedures and culturing methods of material used for the preparation of allergenic extracts on correlation patterns found in allergological testing (skin test and RAST) was investigated. In our laboratory a short extraction procedure performed at O degrees C was used for Aspergillus repens. A. penicilloides, Wallemia sebi, their rearing media and non-inoculated medium. For the commercially available extracts from house dust, house-dust mite, pollen of Dactylus glomerata and A. penicilloides a longer procedure (several days) performed at room temperature was used. Statistical analysis showed a separation of all test results into two clusters, each cluster being composed of correlations between extracts from only one the manufacturers did not show any correlation. The correlations found between the short time incubated extracts of the xerophilic fungi and their rearing media could be explained by genetical and biochemical relationships between these fungi depending on ecological conditions. However, while the correlation found between house dust and house-dust mite is understandable, correlations found between long time incubated extracts from house-dust mite and D. glomerata or A. penicilloides may be nonsense correlations, that do not adequately describe the in vivo situation. The similarity of these extracts is presumably artificially created during extraction.

Evaluation of procedural learning transfer from a virtual environment to a real situation: a case study on tank maintenance training.

PubMed

Ganier, Franck; Hoareau, Charlotte; Tisseau, Jacques

2014-01-01

Virtual reality opens new opportunities for operator training in complex tasks. It lowers costs and has fewer constraints than traditional training. The ultimate goal of virtual training is to transfer knowledge gained in a virtual environment to an actual real-world setting. This study tested whether a maintenance procedure could be learnt equally well by virtual-environment and conventional training. Forty-two adults were divided into three equally sized groups: virtual training (GVT® [generic virtual training]), conventional training (using a real tank suspension and preparation station) and control (no training). Participants then performed the procedure individually in the real environment. Both training types (conventional and virtual) produced similar levels of performance when the procedure was carried out in real conditions. Performance level for the two trained groups was better in terms of success and time taken to complete the task, time spent consulting job instructions and number of times the instructor provided guidance.

Unerupted lower third molar extractions and their risks for mandibular fracture.

PubMed

Corrêa, Ana Paula Simões; Faverani, Leonardo Perez; Ramalho-Ferreira, Gabriel; Ferreira, Sabrina; Ávila Souza, Francisley; de Oliveira Puttini, Igor; Rangel Garcia-Júnior, Idelmo

2014-05-01

As every surgical procedure extraction of third molars can result in several complications, among them the mandibular angle fracture. Predisposing factors for fracture should be analyzed during and after the surgery. This paper aims to discuss the predisposing factors to the occurrence of mandibular angle fractures during and after the procedure for third molars extraction, as well as surgical principles to avoid this complication.

Optimized microwave-assisted extraction of 6-gingerol from Zingiber officinale Roscoeand evaluation of antioxidant activity in vitro.

PubMed

Liu, Wei; Zhou, Chun-Li; Zhao, Jing; Chen, Dong; Li, Quan-Hong

2014-01-01

6-Gingerol is one of the most pharmacologically active and abundant components in ginger, which has a wide array of biochemical and pharmacologic activities. In recent years, the application of microwave-assisted extraction (MAE) for obtaining bioactive compounds from plant materials has shown tremendous research interest and potential. In this study, an efficient microwave-assisted extraction (MAE) technique was developed to extract 6-gingerol from ginger. The extraction efficiency of MAE was also compared with conventional extraction techniques. Fresh gingers (Zingiber officinale Rose.) were harvested at commercial maturity (originally from Shandong, laiwu, China). In single-factor experiments for the recovery of 6-gingerol, proper ranges of ratio of liquid to solid, ethanol proportion, microwave power, extraction time were determined. Based on the values obtained in single-factor experiments, a Box-Behnken design (BBD) was applied to determine the best combination of extraction variables on the yield of 6-gingerol. The optimum extraction conditions were as follows: microwave power 528 W, ratio of liquid to solid 26 mL·g(-1), extraction time 31 s and ethanol proportion 78%. Furthermore, more 6-gingerol and total polyphenols contents were extracted by MAE than conventional methods including Maceration (MAC), Stirring Extraction (SE), Heat reflux extraction (HRE), Ultrasound-assisted extraction (UAE), as well as the antioxidant capacity. Microwave-assisted extraction showed obvious advantages in terms of high extraction efficiency and antioxidant activity of extract within shortest extraction time. Scanning electron microscopy (SEM) images of ginger powder materials after different extractions were obtained to provide visual evidence of the disruption effect. To our best knowledge, this is the first report about usage of MAE of 6-gingerol extraction from ginger, which could be referenced for the extraction of other active compounds from herbal plants.

A new approach for downscaling of electromembrane extraction as a lab on-a-chip device followed by sensitive Red-Green-Blue detection.

PubMed

Baharfar, Mahroo; Yamini, Yadollah; Seidi, Shahram; Arain, Muhammad Balal

2018-05-30

A new design of electromembrane extraction (EME) as a lab on-a-chip device was proposed for the extraction and determination of phenazopyridine as the model analyte. The extraction procedure was accomplished by coupling of EME and the packing of a sorbent. The analyte was extracted under the applied electrical field across a membrane sheet impregnated by nitrophenyl octylether (NPOE) into an acceptor phase. It was followed by the absorption of the analyte on strong cation exchanger as a sorbent. The designed chip contained separate spiral channels for donor and acceptor phases featuring embedded platinum electrodes to enhance extraction efficiency. The selected donor and acceptor phases were 0 mM HCl and 100 mM HCl, respectively. The on-chip electromembrane extraction was carried out under the voltage level of 70 V for 50 min. The analysis was carried out by two modes of a simple Red-Green-Blue (RGB) image analysis tool and a conventional HPLC-UV system. After the absorption of the analyte on the solid phase, its color changed and a digital picture of the sorbent was taken for the RGB analysis. The effective parameters on the performance of the chip device, comprising the EME and solid phase microextraction steps, were distinguished and optimized. The accumulation of the analyte on the solid phase showed excellent sensitivity and a limit of detection (LOD) lower than 1.0 μg L-1 achieved by an image analysis using a smartphone. This device also offered acceptable intra- and inter-assay RSD% (<10%). The calibration curves were linear within the range of 10-1000 μg L-1 and 30-1000 μg L-1 (r2 > 0.9969) for HPLC-UV and RGB analysis, respectively. To investigate the applicability of the method in complicated matrices, urine samples of patients being treated with phenazopyridine were analyzed.

Mercury methylation and reduction potentials in marine water: An improved methodology using 197Hg radiotracer.

PubMed

Koron, Neža; Bratkič, Arne; Ribeiro Guevara, Sergio; Vahčič, Mitja; Horvat, Milena

2012-01-01

A highly sensitive laboratory methodology for simultaneous determination of methylation and reduction of spiked inorganic mercury (Hg(2+)) in marine water labelled with high specific activity radiotracer ((197)Hg prepared from enriched (196)Hg stable isotope) was developed. A conventional extraction protocol for methylmercury (CH(3)Hg(+)) was modified in order to significantly reduce the partitioning of interfering labelled Hg(2+) into the final extract, thus allowing the detection of as little as 0.1% of the Hg(2+) spike transformed to labelled CH(3)Hg(+). The efficiency of the modified CH(3)Hg(+) extraction procedure was assessed by radiolabelled CH(3)Hg(+) spikes corresponding to concentrations of methylmercury between 0.05 and 4ngL(-1). The recoveries were 73.0±6.0% and 77.5±3.9% for marine and MilliQ water, respectively. The reduction potential was assessed by purging and trapping the radiolabelled elemental Hg in a permanganate solution. The method allows detection of the reduction of as little as 0.001% of labelled Hg(2+) spiked to natural waters. To our knowledge, the optimised methodology is among the most sensitive available to study the Hg methylation and reduction potential, therefore allowing experiments to be done at spikes close to natural levels (1-10ngL(-1)). Copyright © 2011 Elsevier Ltd. All rights reserved.

Evaluation of Flow-Injection Tandem Mass Spectrometry for Rapid and High-Throughput Quantitative Determination of B-Vitamins in Nutritional Supplements

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

Bhandari, Deepak; Van Berkel, Gary J

2012-01-01

The use of flow-injection electrospray ionization tandem mass spectrometry for rapid and high-throughput mass spectral analysis of selected B-vitamins, viz. B1, B2, B3, B5, and B6, in nutritional formulations was demonstrated. A simple and rapid (~5 min) in-tube sample preparation was performed by adding extraction solvent to a powdered sample aliquot followed by agitation, centrifugation, and filtration to recover an extract for analysis. Automated flow injection introduced 1 L of the extracts directly into the mass spectrometer ion source without chromatographic separation. Sample-to-sample analysis time was 60 s representing significant improvement over conventional liquid chromatography approaches which typically require 25-45more » min, and often require more significant sample preparation procedures. Quantitative capabilities of the flow-injection analysis were tested using the method of standard additions and NIST standard reference material (SRM 3280) multivitamin/multielement tablets. The quantity determined for each B-vitamin in SRM 3280 was within the statistical range provided for the respective certified values. The same sample preparation and analysis approach was also applied to two different commercial vitamin supplement tablets and proved to be successful in the quantification of the selected B-vitamins as evidenced by an agreement with the labels values and the results obtained using isotope dilution liquid chromatography/mass spectrometry.« less

Systemic inflammatory response after endoscopic (TEP) vs Shouldice groin hernia repair.

PubMed

Schwab, R; Eissele, S; Brückner, U B; Gebhard, F; Becker, H P

2004-08-01

Endoscopic techniques are commonly used for many different types of surgery. It is claimed that videoendoscopic procedures have the advantage of being less traumatic and of offering higher postoperative patient comfort than conventional open techniques. The extent of tissue trauma can be evaluated on the basis of the inflammatory response observed in the wake of surgery. Available studies that have compared endoscopic and conventional techniques suggest that endoscopic cholecystectomy, laparoscopic colorectal resection, and thoracoscopic pulmonary resection have immunologic advantages over conventional approaches. The objective of this prospective study was to determine whether endoscopic hernia repair techniques are also preferable to conventional procedures and to what extent the anesthetic technique (local or general anesthesia) influences the postoperative inflammatory response. For this purpose, biochemical monitoring of cytokine activity [C-reactive protein (CRP), prostaglandin F1alpha (PGF1alpha), neopterin, interleukin-6 (IL-6)] was done prospectively in 101 patients [totally extraperitoneal approach (TEP) n=32, unilateral n=12, bilateral n=20; Shouldice n=69, local anesthesia (LA) n=23, general anesthesia (GA) n=46] before and until 3 days after surgery. The parameters IL-6 and PGF1alpha suggested that the immune trauma immediately after surgery was significantly higher in the group of patients with endoscopic hernia repair than in the group of patients who received a Shouldice repair. No significant differences were observed after the first postoperative day. A comparison between the TEP group and the patients who received conventional surgery under local anesthesia showed that the TEP approach was also associated with a higher postoperative neopterin level. Within the first 3 days after surgical intervention, bilateral endoscopic hernia repair induced no significantly higher inflammatory response than the surgical treatment of unilateral conditions. The anesthetic procedure that was used in the Shouldice operation had no significant effect on inflammatory response. Unlike other types of endoscopic surgery, the repair of groin hernias using an endoscopic technique cannot be regarded as a minimally invasive procedure that is less traumatic than conventional approaches. Instead, the conventional Shouldice procedure appears to cause the lowest inflammatory response and to be the least traumatic approach to hernia repair, especially when it is performed under local anesthesia.

Magnetic navigation system and CT roadmap-assisted percutaneous coronary intervention: a comparison to the conventional approach.

PubMed

Hao, Ruina; Zhang, Qiu; Xu, Zhuowen; Tang, Lijun; Yang, Zhijian; Cao, Kejiang; Li, Chunjian

2013-04-01

Computed tomography coronary angiography (CTCA) has been successfully integrated with the magnetic navigation system (MNS) to facilitate a roadmap-assisted percutaneous coronary intervention (PCI). The aim of this study was to compare this new approach of PCI versus conventional PCI regarding the difference of contrast usage, x-ray exposure, procedure success, and in-hospital expenses. Thirty-eight patients with stable coronary artery disease and coronary artery lesions of ≥70% diameter stenosis diagnosed by both pre-procedure CTCA and coronary angiography (CAG) were enrolled to receive the MNS and CT roadmap-assisted PCI. Another 38 patients were consecutively recruited to receive conventional PCI, matched with the MNS group by the vessel and lesion type base on American College of Cardiology/American Heart Association criteria. Regarding the process of the guidewire placement, wherein the technical difference of the two procedures exists, the median contrast usage for guidewire crossing was significantly lower in the MNS group than in the conventional group [0.0 mL (interquartile range [IQR], 0.0-3.0 mL) vs 5.0 mL (IQR, 3.1-6.8 mL); P<.001], with zero contrast usage in 25 of the 44 guidewire placements in the MNS group, but in none of the conventional group; the radiation dosage for guidewire crossing in the MNS group was also significantly lower than in the conventional group (235.8 μGym² [IQR, 134.9-455.1 μGym²] vs 364.4 μGym² [IQR, 223.4-547.2 μGym²]; P=.033). There were no significant differences between the two groups concerning the total contrast usage, total radiation dosage of the PCI, the procedural fees, or the overall in-hospital expenses. All of the enrolled vessels were successfully intervened in both groups. In PCI of simple lesions, the application of CT guidance and magnetic navigation had modest impacts on radiation dosage and contrast usage for wire crossing, but no impact on overall radiation dosage or contrast usage for the procedure. In addition, the use of CT roadmap and MNS was likely more expensive compared to PCI using conventional radiographic technique.

Surfactant assisted pulsed two-phase electromembrane extraction followed by GC analysis for quantification of basic drugs in biological samples.

PubMed

Zahedi, Pegah; Davarani, Saied Saeed Hosseiny; Moazami, Hamid Reza; Nojavan, Saeed

2016-01-05

In this work, a simple and efficient surfactant assisted pulsed two-phase electromembrane extraction (SA-PEME) procedure combined with gas chromatography (GC) has been developed for the determination of alfentanil, sufentanil and methadone in various samples. It has been found that the addition of anionic surfactant causes the accumulation of the cationic analytes at the SLM/solution interface resulting in an easier transfer of the analytes into the organic phase. The method was accomplished with 1-octanol as the acceptor phase and supported liquid membrane (SLM) by means of an 80 V pulsed electrical driving force and the extraction time of 20 min. The model analytes were extracted from 3.0 mL sample solution (pH 4.0) containing 0.02% w/v surfactant (sodium dodecyl sulfate). The duty cycle of 92% and frequency of 0.357 Hz gave the best performance. Extraction recoveries in the range of 70.5-95.2% and satisfactory repeatability (7.6

Bactericidal effect of extracts and metabolites of Robinia pseudoacacia L. on Streptococcus mutans and Porphyromonas gingivalis causing dental plaque and periodontal inflammatory diseases.

PubMed

Patra, Jayanta Kumar; Kim, Eun Sil; Oh, Kyounghee; Kim, Hyeon-Jeong; Dhakal, Radhika; Kim, Yangseon; Baek, Kwang-Hyun

2015-04-08

The mouth cavity hosts many types of anaerobic bacteria, including Streptococcus mutans and Porphyromonas gingivalis, which cause periodontal inflammatory diseases and dental caries. The present study was conducted to evaluate the antibacterial potential of extracts of Robinia pseudoacacia and its different fractions, as well as some of its natural compounds against oral pathogens and a nonpathogenic reference bacteria, Escherichia coli. The antibacterial activity of the crude extract and the solvent fractions (hexane, chloroform, ethyl acetate and butanol) of R. pseudoacacia were evaluated against S. mutans, P. gingivalis and E. coli DH5α by standard micro-assay procedure using conventional sterile polystyrene microplates. The results showed that the crude extract was more active against P. gingivalis (100% growth inhibition) than against S. mutans (73% growth inhibition) at 1.8 mg/mL. The chloroform and hexane fractions were active against P. gingivalis, with 91 and 97% growth inhibition, respectively, at 0.2 mg/mL. None of seven natural compounds found in R. pseudoacacia exerted an antibacterial effect on P. gingivalis; however, fisetin and myricetin at 8 µg/mL inhibited the growth of S. mutans by 81% and 86%, respectively. The crude extract of R. pseudoacacia possesses bioactive compounds that could completely control the growth of P. gingivalis. The antibiotic activities of the hexane and chloroform fractions suggest that the active compounds are hydrophobic in nature. The results indicate the effectiveness of the plant in clinical applications for the treatment of dental plaque and periodontal inflammatory diseases and its potential use as disinfectant for various surgical and orthodontic appliances.

Precipitate statistics in an Al-Mg-Si-Cu alloy from scanning precession electron diffraction data

NASA Astrophysics Data System (ADS)

Sunde, J. K.; Paulsen, Ø.; Wenner, S.; Holmestad, R.

2017-09-01

The key microstructural feature providing strength to age-hardenable Al alloys is nanoscale precipitates. Alloy development requires a reliable statistical assessment of these precipitates, in order to link the microstructure with material properties. Here, it is demonstrated that scanning precession electron diffraction combined with computational analysis enable the semi-automated extraction of precipitate statistics in an Al-Mg-Si-Cu alloy. Among the main findings is the precipitate number density, which agrees well with a conventional method based on manual counting and measurements. By virtue of its data analysis objectivity, our methodology is therefore seen as an advantageous alternative to existing routines, offering reproducibility and efficiency in alloy statistics. Additional results include improved qualitative information on phase distributions. The developed procedure is generic and applicable to any material containing nanoscale precipitates.

Antero mediastinal retrosternal goiter: surgical excision by combined cervical and hybrid robot-assisted approach

PubMed Central

Cicalese, Marcellino; Scaramuzzi, Roberto; Di Natale, Davide; Curcio, Carlo

2018-01-01

Most intrathoracic goiters are located in the anterior mediastinum. Surgical resection is usually recommended in case of morbidity associated with the goiter’s mass effect or for suspicion of malignancy difficult to diagnose without resection. Intrathoracic goiters are usually resected through a cervical approach, with sternotomy needed in selected cases. We report a case of antero mediastinal retrosternal goiter in old age patient undergoing surgical excision by combined cervical and hybrid robot-assisted approach. All steps of the thoracic procedure were completely performed using the da Vinci robot system with final extension of a port-site incision to extract the specimen. This approach provides more advantages than sternotomy regarding post operative clinical benefits and allows a more accurate surgical resection in the antero-superior mediastinum than conventional thoracoscopy. PMID:29707373

A standardized method for sampling and extraction methods for quantifying microplastics in beach sand.

PubMed

Besley, Aiken; Vijver, Martina G; Behrens, Paul; Bosker, Thijs

2017-01-15

Microplastics are ubiquitous in the environment, are frequently ingested by organisms, and may potentially cause harm. A range of studies have found significant levels of microplastics in beach sand. However, there is a considerable amount of methodological variability among these studies. Methodological variation currently limits comparisons as there is no standard procedure for sampling or extraction of microplastics. We identify key sampling and extraction procedures across the literature through a detailed review. We find that sampling depth, sampling location, number of repeat extractions, and settling times are the critical parameters of variation. Next, using a case-study we determine whether and to what extent these differences impact study outcomes. By investigating the common practices identified in the literature with the case-study, we provide a standard operating procedure for sampling and extracting microplastics from beach sand. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of a Novel Catheter Tracking System on Radiation Exposure during the Procedural Phases of Atrial Fibrillation and Flutter Ablation.

PubMed

Malliet, Nicolas; Andrade, Jason G; Khairy, Paul; Thanh, Hien Kiem Nguyen; Venier, Sandrine; Dubuc, Marc; Dyrda, Katia; Guerra, Peter; Mondésert, Blandine; Rivard, Léna; Tadros, Rafik; Talajic, Mario; Thibault, Bernard; Roy, Denis; Macle, Laurent

2015-07-01

Fluoroscopic guidance is used to position catheters during cardiac ablation. We evaluated the impact of a novel nonfluoroscopic sensor-guided electromagnetic navigation system (MG) on radiation exposure during catheter ablation of atrial fibrillation (AF) or atrial flutter (AFL). A total of 134 consecutive patients referred for ablation of AF (n = 44) or AFL (n = 90) ablation were prospectively enrolled. In one group the MG system was used for nonfluoroscopic catheter positioning, whereas in the conventional group standard fluoroscopy was utilized. Fluoroscopy times were assessed for each stage of procedure and total radiation exposure was quantified. Patient characteristics were similar between the groups. The procedural end point was achieved in all. Median (interquartile range [IQR]) fluoroscopy times were 12.5 minutes (7.6, 17.4) MG group versus 21.5 minutes (15.3, 23.0) conventional group (P < 0.0001) for AF ablation, and 0.8 minutes (0.4, 2.5) MG group versus 9.9 minutes (5.1, 22.5) conventional group (P < 0.0001) for AFL ablation. Median (IQR) total radiation exposure (μGy·m(2)) was 1,107 (906, 2,033) MG group versus 2,835 (1,688, 3,855) conventional group (P = 0.0001) for AF ablation, and 161 (65, 537) MG group versus 1,651 (796, 4,569) conventional group (P < 0.0001) for AFL ablation. No difference in total procedural time was seen. The use of a novel nonfluoroscopic catheter tracking system is associated with a significant reduction in radiation exposure during AF and AFL ablation (61% and 90% reduction, respectively). In the era of heightened awareness of the importance of radiation reduction, this system represents a safe and efficient tool to decrease radiation exposure during electrophysiological ablation procedures. ©2015 Wiley Periodicals, Inc.

The effect of different conventional methods of extraction on Marantodes pumila var. pumila leaves in relation to free radical scavenging activity

NASA Astrophysics Data System (ADS)

Hamid, Noor Huda Abd; Latip, Jalifah; Markom, Masturah

2018-04-01

Marantodes pumila is one of the important herbs used in traditional medicine. However, there is no report on the optimum method for the preparation of M. pumila extract enriched with bioactive compounds. Therefore, this study aim to establish the suitable method in the preparation of M. pumila extracts enriched with antioxidative compounds. Different conventional extraction methods such as maceration, reflux and Soxhlet in solvents of different polarities i.e. ethanol, 50 % aqueous ethanol and water were employed to prepare extracts. Constituents of each extract were profiled using RP-HPLC followed by the free radical scavenging assay using 2,2 diphenyl-1-picrylhydrazyl (DPPH) to determine the antioxidant activity. Among all extraction methods, maceration in 50 % aqueous ethanol gave the highest total percentage yield (22.41 %) while all extraction methods were able to extract the marker compounds, gallic acid (GA) and methyl gallate (MGA). The free radical scavenging activity of extracts varied from IC50 11.93 µg/mL (50 % aqueous ethanol via reflux) to 64.15 µg/mL (water via maceration). All extracts showed better scavenging activity as compared to synthetic antioxidant, BHT. The variation in the IC50 values is expected due to the presence of different types and/or concentration of bioactive compounds in each extract. This study may provide a preliminary insight for the preparation of standardized extracts of M. pumila enriched with bioactive compounds.

Laboratory Production of Lemon Liqueur (Limoncello) by Conventional Maceration and a Two-Syringe System to Illustrate Rapid Solid-Liquid Dynamic Extraction

ERIC Educational Resources Information Center

Naviglio, Daniele; Montesano, Domenico; Gallo, Monica

2015-01-01

Two experimental techniques of solid-liquid extraction are compared relating to the lab-scale production of lemon liqueur, most commonly named "limoncello"; the first is the official method of maceration for the solid-liquid extraction of analytes and is widely used to extract active ingredients from a great variety of natural products;…

Experimental and computational studies on molecularly imprinted solid-phase extraction for gonyautoxins 2,3 from dinoflagellate Alexandrium minutum.

PubMed

Lian, Ziru; Li, Hai-Bei; Wang, Jiangtao

2016-08-01

An innovative and effective extraction procedure based on molecularly imprinted solid-phase extraction (MISPE) was developed for the isolation of gonyautoxins 2,3 (GTX2,3) from Alexandrium minutum sample. Molecularly imprinted polymer microspheres were prepared by suspension polymerization and and were employed as sorbents for the solid-phase extraction of GTX2,3. An off-line MISPE protocol was optimized. Subsequently, the extract samples from A. minutum were analyzed. The results showed that the interference matrices in the extract were obviously cleaned up by MISPE procedures. This outcome enabled the direct extraction of GTX2,3 in A. minutum samples with extraction efficiency as high as 83 %, rather significantly, without any need for a cleanup step prior to the extraction. Furthermore, computational approach also provided direct evidences of the high selective isolation of GTX2,3 from the microalgal extracts.

Solvent-free microwave extraction of essential oil from aromatic herbs: from laboratory to pilot and industrial scale.

PubMed

Filly, Aurore; Fernandez, Xavier; Minuti, Matteo; Visinoni, Francesco; Cravotto, Giancarlo; Chemat, Farid

2014-05-01

Solvent-free microwave extraction (SFME) has been proposed as a green method for the extraction of essential oil from aromatic herbs that are extensively used in the food industry. This technique is a combination of microwave heating and dry distillation performed at atmospheric pressure without any added solvent or water. The isolation and concentration of volatile compounds is performed in a single stage. In this work, SFME and a conventional technique, hydro-distillation HD (Clevenger apparatus), are used for the extraction of essential oil from rosemary (Rosmarinus officinalis L.) and are compared. This preliminary laboratory study shows that essential oils extracted by SFME in 30min were quantitatively (yield and kinetics profile) and qualitatively (aromatic profile) similar to those obtained using conventional hydro-distillation in 2h. Experiments performed in a 75L pilot microwave reactor prove the feasibility of SFME up scaling and potential industrial applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

Optimization of orodispersible and conventional tablets using simplex lattice design: Relationship among excipients and banana extract.

PubMed

Duangjit, Sureewan; Kraisit, Pakorn

2018-08-01

The objective of this study was focused on the optimization of the pharmaceutical excipients and banana extract in the preparation of orally disintegrating banana extract tablets (OD-BET) and conventional banana extract tablets (CO-BET) using a simplex lattice design. Various ratios of banana extract (BE), dibasic calcium phosphate (DCP) and microcrystalline cellulose (MCC) were used to prepare banana extract tablets (BET). The results indicated that the optimal OD-BET and CO-BET consisted of BE: DCP: MCC at 10.0, 88.8, 1.2, 10.0, 83.8: and 6.2, respectively. AFM demonstrated that the surface of BET with BE + MCC was smooth and compacted when compared to BET with BE + DCP + MCC and BE + DCP. FTIR and XRD showed a correlation in the results and indicated that no interaction of each ingredient occurred in the process of BET formulation. Therefore, the experimental design is potentially useful in formulated OD-BET and CO-BET by using only one design simultaneously. Copyright © 2018 Elsevier Ltd. All rights reserved.

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.

Comparison of results from simple expressions for MOSFET parameter extraction

NASA Technical Reports Server (NTRS)

Buehler, M. G.; Lin, Y.-S.

1988-01-01

In this paper results are compared from a parameter extraction procedure applied to the linear, saturation, and subthreshold regions for enhancement-mode MOSFETs fabricated in a 3-micron CMOS process. The results indicate that the extracted parameters differ significantly depending on the extraction algorithm and the distribution of I-V data points. It was observed that KP values vary by 30 percent, VT values differ by 50 mV, and Delta L values differ by 1 micron. Thus for acceptance of wafers from foundries and for modeling purposes, the extraction method and data point distribution must be specified. In this paper measurement and extraction procedures that will allow a consistent evaluation of measured parameters are discussed.

Determination of available phosphorus in soils by using a new extraction procedure and a flow injection amperometric system.

PubMed

Jakmunee, Jaroon; Junsomboon, Jaroon

2009-09-15

A new extraction procedure based on an off-line extraction column was proposed for extracting of available phosphorus from soils. The column was fabricated from a plastic syringe fitted at the bottom with a cotton wool and a piece of filter paper to support a soil sample. An aliquot (50 mL) of extracting solution (0.05 M HCl+0.0125 M H(2)SO(4)) was used to extract the sample under gravity flow and the eluate was collected in a polyethylene bottle. The extract was then analyzed for phosphorus contents by a simple flow injection amperometric system, employing a set of three-way solenoid valves as an injection valve. The method is based on the electrochemical reduction of 12-molybdophosphate which is produced on-line by the reaction of orthophosphate with acidic molybdate and the electrical current produced was directly proportional to the concentration of phosphate in range of 0.1-10.0 mg L(-1) PO(4)-P, with a detection limit of 0.02 mg L(-1). Relative standard for 11 replicate injections of 5 mg L(-1) PO(4)-P was 0.5%. A sample through put of 35 h(-1) was achieved, with consumption of 14 mg KCl, 10mg ammonium molybdate and 0.05 mL H(2)SO(4) per analysis. The detection system does not suffer from the interferences that are encountered in the photometric method such as colored substances, colloids, metal ions, silicate and refractive index effect (Schlieren effect). The results obtained by the column extraction procedure were well correlated with those obtained by the steady-state extraction procedure, but showed slightly higher extraction efficiency.

Tube thoracostomy training with a medical simulator is associated with faster, more successful performance of the procedure

PubMed Central

Chung, Tae Nyoung; Kim, Sun Wook; You, Je Sung; Chung, Hyun Soo

2016-01-01

Objective Tube thoracostomy (TT) is a commonly performed intensive care procedure. Simulator training may be a good alternative method for TT training, compared with conventional methods such as apprenticeship and animal skills laboratory. However, there is insufficient evidence supporting use of a simulator. The aim of this study is to determine whether training with medical simulator is associated with faster TT process, compared to conventional training without simulator. Methods This is a simulation study. Eligible participants were emergency medicine residents with very few (≤3 times) TT experience. Participants were randomized to two groups: the conventional training group, and the simulator training group. While the simulator training group used the simulator to train TT, the conventional training group watched the instructor performing TT on a cadaver. After training, all participants performed a TT on a cadaver. The performance quality was measured as correct placement and time delay. Subjects were graded if they had difficulty on process. Results Estimated median procedure time was 228 seconds in the conventional training group and 75 seconds in the simulator training group, with statistical significance (P=0.040). The difficulty grading did not show any significant difference among groups (overall performance scale, 2 vs. 3; P=0.094). Conclusion Tube thoracostomy training with a medical simulator, when compared to no simulator training, is associated with a significantly faster procedure, when performed on a human cadaver. PMID:27752610

CTEPP STANDARD OPERATING PROCEDURE FOR EXTRACTING AND PREPARING SOLID FOOD SAMPLES FOR ANALYSIS OF PERSISTENT ORGANIC POLLUTANTS (SOP-5.20)

EPA Science Inventory

This SOP describes the procedures for homogenizing, extracting and concentrating solid food samples for persistent organic pollutants such as organochlorine compounds, organophosphate compounds, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, substituted phenols, and...

CTEPP STANDARD OPERATING PROCEDURE FOR DETECTION AND QUANTIFICATION OF TARGET ANALYTES BY GAS CHROMATOGRAPHY/MASS SPECTROMETRY (GC/MS) (SOP-5.24)

EPA Science Inventory

This standard operating procedure describes the method used for the determination of target analytes in sample extracts and related quality assurance/quality control sample extracts generated in the CTEPP study.

CTEPP STANDARD OPERATING PROCEDURE FOR EXTRACTING AND PREPARING LIQUID FOOD SAMPLES FOR ANALYSIS OF PERSISTENT ORGANIC POLLUTANTS (SOP-5.19)

EPA Science Inventory

This SOP describes the procedures for homogenizing, extracting, and concentrating liquid food samples for neutral persistent organic pollutants such as organochlorine compounds, organophosphate compounds, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and phenols.

Monitoring Impact of a Pesticide Treatment on Bacterial Soil Communities by Metabolic and Genetic Fingerprinting in Addition to Conventional Testing Procedures

PubMed Central

Engelen, Bert; Meinken, Kristin; von Wintzingerode, Friedrich; Heuer, Holger; Malkomes, Hans-Peter; Backhaus, Horst

1998-01-01

Herbogil (dinoterb), a reference herbicide, the mineral oil Oleo (paraffin oil used as an additive to herbicides), and Goltix (metamitron) were taken as model compounds for the study of impacts on microbial soil communities. After the treatment of soil samples, effects on metabolic sum parameters were determined by monitoring substrate-induced respiration (SIR) and dehydrogenase activity, as well as carbon and nitrogen mineralization. These conventional ecotoxicological testing procedures are used in pesticide registration. Inhibition of biomass-related activities and stimulation of nitrogen mineralization were the most significant effects caused by the application of Herbogil. Even though Goltix and Oleo were used at a higher dosage (10 times higher), the application of Goltix resulted in smaller effects and the additive Oleo was the least-active compound, with minor stimulation of test parameters at later observation times. The results served as a background for investigation of the power of “fingerprinting” methods in microbial ecology. Changes in catabolic activities induced by treatments were analyzed by using the 95 carbon sources provided by the BIOLOG system. Variations in the complex metabolic fingerprints demonstrated inhibition of many catabolic pathways after the application of Herbogil. Again, the effects of the other compounds were expressed at much lower levels and comprised stimulations as well as inhibitions. Testing for significance by a multivariate t test indicated that the sensitivity of this method was similar to the sensitivities of the conventional testing procedures. The variation of sensitive carbon sources, as determined by factor weights at different observation times, indicated the dynamics of the community shift induced by the Herbogil treatment in more detail. DNA extractions from soil resulted in a collection of molecules representing the genetic composition of total bacterial communities. Distinct and highly reproducible community patterns, or genetic fingerprints, resulting from application of the different herbicides were obtained by the sequence-specific separation of partial 16S rDNA amplification products in temperature gradient gel electrophoresis. Significant pattern variations were quantified. For detailed analysis, application-responsive bands from the Herbogil and Oleo treatments were sequenced and their tentative phylogenetic positions were identified. Data interpretation and the potentials and biases of the additional observation windows on microbial communities are discussed. PMID:9687435

Immobilization of microalgae cells in alginate facilitates isolation of DNA and RNA.

PubMed

Lopez, Blanca R; Hernandez, Juan-Pablo; Bashan, Yoav; de-Bashan, Luz E

2017-04-01

Isolation of nucleic acids from Chlorella is difficult, given the chemically complex nature of their cell walls and variable production of metabolites. Immobilization of microalgae in polymers adds additional difficulty. Here, we modified, amended, and standardized methods for isolation of nucleic acids and compared the yield of DNA and RNA from free-living and encapsulated microalgae C. sorokiniana. Isolation of nucleic acids from immobilized cells required two steps in dissolving the alginate matrix, releasing the cells, and mechanical disruption with glass beads. For DNA extraction, we used modified versions of a commercial kit along with the hexadecyltrimethylammonium bromide (CTAB) method. For RNA extraction, we used the commercial TRI reagent procedure and the CTAB-dithiotreitol method. Quantity and quality of nucleic acids in extracts varied with growth conditions, isolation procedures, and time of incubation of the original culture. There were consistently higher amounts of DNA and RNA in extracts from immobilized cells. Quantitatively, the modified procedure with the commercial Promega kit was the most reliable procedure for isolating DNA and a modified commercial TRI reagent procedure was the choice for isolating RNA. All four procedures eliminated proteins efficiently and had low levels of contamination from residual polysaccharides from the matrices and/or metabolites naturally produced by the microalgae. All DNA extracts under both growth conditions, time of incubation, and two isolation methods successfully amplified the 18S ribosomal RNA by PCR and quantitative reverse transcription (RT-qPCR). Copyright © 2017 Elsevier B.V. All rights reserved.

When is rotational angiography superior to conventional single-plane angiography for planning coronary angioplasty?

PubMed

Morris, Paul D; Taylor, Jane; Boutong, Sara; Brett, Sarah; Louis, Amal; Heppenstall, James; Morton, Allison C; Gunn, Julian P

2016-03-01

To investigate the value of rotational coronary angiography (RoCA) in the context of percutaneous coronary intervention (PCI) planning. As a diagnostic tool, RoCA is associated with decreased patient irradiation and contrast use compared with conventional coronary angiography (CA) and provides superior appreciation of three-dimensional anatomy. However, its value in PCI remains unknown. We studied stable coronary artery disease assessment and PCI planning by interventional cardiologists. Patients underwent either RoCA or conventional CA pre-PCI for planning. These were compared with the referral CA (all conventional) in terms of quantitative lesion assessment and operator confidence. An independent panel reanalyzed all parameters. Six operators performed 127 procedures (60 RoCA, 60 conventional CA, and 7 crossed-over) and assessed 212 lesions. RoCA was associated with a reduction in the number of lesions judged to involve a bifurcation (23 vs. 30 lesions, P < 0.05) and a reduction in the assessment of vessel caliber (2.8 vs. 3.0 mm, P < 0.05). RoCA improved confidence assessing lesion length (P = 0.01), percentage stenosis (P = 0.02), tortuosity (P < 0.04), and proximity to a bifurcation (P = 0.03), particularly in left coronary artery cases. X-ray dose, contrast agent volume, and procedure duration were not significantly different. Compared with conventional CA, RoCA augments quantitative lesion assessment, enhances confidence in the assessment of coronary artery disease and the precise details of the proposed procedure, but does not affect X-ray dose, contrast agent volume, or procedure duration. © 2015 The Authors. Catheterization and Cardiovascular Interventions. Published by Wiley Periodicals, Inc.

Isolation and characterization of coagulant extracted from Moringa oleifera seed by salt solution.

PubMed

Okuda, T; Baes, A U; Nishijima, W; Okada, M

2001-02-01

It is known that M. oleifera contains a natural coagulant in the seeds. In our previous research, the method using salt water to extract the active coagulation component from M. oleifera seeds was developed and compared with the conventional method using water. In this research, the active coagulation component was purified from a NaCl solution crude extract of Moringa oleifera seeds. The active component was isolated and purified from the crude extract through a sequence of steps that included salting-out by dialysis, removal of lipids and carbohydrates by homogenization with acetone, and anion exchange. Specific coagulation activity of the active material increased up to 34 times more than the crude extract after the ion exchange. The active component was not the same as that of water extract. The molecular weight was about 3000 Da. The Lowry method and the phenol-sulfuric acid method indicated that the active component was neither protein nor polysaccharide. The optimum pH of the purified active component for coagulation of turbidity was pH 8 and above. Different from the conventional water extracts, the active component can be used for waters with low turbidity without increase in the dissolved organic carbon concentration.

Modified extraction procedure for gas-liquid chromatography applied to the identification of anaerobic bacteria.

PubMed Central

Thomann, W R; Hill, G B

1986-01-01

Chloroform and ether commonly are used as solvents to extract metabolic organic acids for analysis by gas-liquid chromatography in the identification of anaerobic bacteria. Because these solvents are potentially hazardous to personnel, modified extraction procedures involving the use of a safer solvent, methyl tert-butyl ether were developed which remained both simple to perform and effective for organism identification. PMID:3700623

Cost analysis of conventional facial reconstruction procedures followed by face transplantation.

PubMed

Siemionow, M; Gatherwright, J; Djohan, R; Papay, F

2011-02-01

For the first time, this study analyzes the cost of multiple conventional reconstructions and face transplantation in a single patient. This patient is a 46-year-old female victim of a shotgun blast resulting in loss of multiple functional and aesthetic subunits. For over 5 years, she underwent multiple conventional reconstructions with suboptimal results. In December 2008, she became the recipient of the first U.S. face transplant. This has provided the unique opportunity to present the cost of 23 separate conventional reconstructive procedures and the first face transplant in the United States. The combined cost of conventional reconstructive procedures and the first U.S. face transplant was calculated to be $353 480 and $349 959, respectively. The combined cost posttransplant totaled $115 463. The direct cost pretransplant was $206 646, $232 893 peritransplant and $74 236 posttransplant. The two largest areas of cost utilization were surgical ($79 625; 38.5%) and nursing ($55 860; 27%), followed by anesthesia ($24 808; 12%) and pharmacy ($16 581; 8%). This study demonstrates that the cost of the first U.S. face transplant is similar to multiple conventional reconstructions. Although the cost of facial transplantation is considerable, the alleviation of psychological and physiological suffering, exceptional functional recovery and fulfillment of long-lasting hope for social reintegration may be priceless. ©2011 The Authors Journal compilation©2011 The American Society of Transplantation and the American Society of Transplant Surgeons.

Comparison of conventional versus Hybrid knife peroral endoscopic myotomy methods for esophageal achalasia: a case-control study.

PubMed

Tang, Xiaowei; Gong, Wei; Deng, Zhiliang; Zhou, Jieqiong; Ren, Yutang; Zhang, Qiang; Chen, Zhenyu; Jiang, Bo

2016-01-01

Peroral endoscopic myotomy (POEM) has been developed to treat achalasia as a novel less invasive modality. We aimed to compare the efficacy and safety of conventional knife versus Hybrid knife (HK) during POEM procedure. Between June 2012 and July 2014, 31 patients underwent POEM using HK in our department (HK group), and 36 patients underwent POEM using conventional method (injection needle and triangular tip [TT] knife, TT group). Procedure-related parameters, symptom relief, adverse events were compared between two groups. There were no significant differences in the age, sex and other baseline characteristics between the two groups. The mean procedural time was significantly shorter in HK group than TT group (53.0 ± 17.2 vs. 67.6 ± 28.4 min, p = 0.015). The mean frequency of devices exchange was 4.7 ± 1.7 in HK group and 10.9 ± 1.8 in TT group (p = 0.000). No serious adverse events occurred postoperatively in both groups. At one-year follow-up, a total of 94% treatment success was achieved in all patients (93.5% in HK group and 94.4% in TT group, p = 0.877). HK in POEM can shorten the procedural time, and achieve similar treatment success compared to conventional TT knife.

Convolutional Neural Network-Based Finger-Vein Recognition Using NIR Image Sensors

PubMed Central

Hong, Hyung Gil; Lee, Min Beom; Park, Kang Ryoung

2017-01-01

Conventional finger-vein recognition systems perform recognition based on the finger-vein lines extracted from the input images or image enhancement, and texture feature extraction from the finger-vein images. In these cases, however, the inaccurate detection of finger-vein lines lowers the recognition accuracy. In the case of texture feature extraction, the developer must experimentally decide on a form of the optimal filter for extraction considering the characteristics of the image database. To address this problem, this research proposes a finger-vein recognition method that is robust to various database types and environmental changes based on the convolutional neural network (CNN). In the experiments using the two finger-vein databases constructed in this research and the SDUMLA-HMT finger-vein database, which is an open database, the method proposed in this research showed a better performance compared to the conventional methods. PMID:28587269

Convolutional Neural Network-Based Finger-Vein Recognition Using NIR Image Sensors.

PubMed

Hong, Hyung Gil; Lee, Min Beom; Park, Kang Ryoung

2017-06-06

Conventional finger-vein recognition systems perform recognition based on the finger-vein lines extracted from the input images or image enhancement, and texture feature extraction from the finger-vein images. In these cases, however, the inaccurate detection of finger-vein lines lowers the recognition accuracy. In the case of texture feature extraction, the developer must experimentally decide on a form of the optimal filter for extraction considering the characteristics of the image database. To address this problem, this research proposes a finger-vein recognition method that is robust to various database types and environmental changes based on the convolutional neural network (CNN). In the experiments using the two finger-vein databases constructed in this research and the SDUMLA-HMT finger-vein database, which is an open database, the method proposed in this research showed a better performance compared to the conventional methods.

Accurate Modeling Method for Cu Interconnect

NASA Astrophysics Data System (ADS)

Yamada, Kenta; Kitahara, Hiroshi; Asai, Yoshihiko; Sakamoto, Hideo; Okada, Norio; Yasuda, Makoto; Oda, Noriaki; Sakurai, Michio; Hiroi, Masayuki; Takewaki, Toshiyuki; Ohnishi, Sadayuki; Iguchi, Manabu; Minda, Hiroyasu; Suzuki, Mieko

This paper proposes an accurate modeling method of the copper interconnect cross-section in which the width and thickness dependence on layout patterns and density caused by processes (CMP, etching, sputtering, lithography, and so on) are fully, incorporated and universally expressed. In addition, we have developed specific test patterns for the model parameters extraction, and an efficient extraction flow. We have extracted the model parameters for 0.15μm CMOS using this method and confirmed that 10%τpd error normally observed with conventional LPE (Layout Parameters Extraction) was completely dissolved. Moreover, it is verified that the model can be applied to more advanced technologies (90nm, 65nm and 55nm CMOS). Since the interconnect delay variations due to the processes constitute a significant part of what have conventionally been treated as random variations, use of the proposed model could enable one to greatly narrow the guardbands required to guarantee a desired yield, thereby facilitating design closure.

A New Method for Calculating Counts in Cells

NASA Astrophysics Data System (ADS)

Szapudi, István

1998-04-01

In the near future, a new generation of CCD-based galaxy surveys will enable high-precision determination of the N-point correlation functions. The resulting information will help to resolve the ambiguities associated with two-point correlation functions, thus constraining theories of structure formation, biasing, and Gaussianity of initial conditions independently of the value of Ω. As one of the most successful methods of extracting the amplitude of higher order correlations is based on measuring the distribution of counts in cells, this work presents an advanced way of measuring it with unprecedented accuracy. Szapudi & Colombi identified the main sources of theoretical errors in extracting counts in cells from galaxy catalogs. One of these sources, termed as measurement error, stems from the fact that conventional methods use a finite number of sampling cells to estimate counts in cells. This effect can be circumvented by using an infinite number of cells. This paper presents an algorithm, which in practice achieves this goal; that is, it is equivalent to throwing an infinite number of sampling cells in finite time. The errors associated with sampling cells are completely eliminated by this procedure, which will be essential for the accurate analysis of future surveys.

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.

Incidence of Trismus in Transalveolar Extraction of Lower Third Molar.

PubMed

Balakrishnan, Gowri; Narendar, Ramesh; Kavin, Thangavelu; Venkataraman, Sivasubramanian; Gokulanathan, Subramaniam

2017-11-01

Conventional mandibular third molar removal produces tissue trauma that induces an inflammatory reaction, leading to postoperative sequelae, the most common ones being trismus which influences the patient's quality of life in the postoperative period. Identifying the factors determining trismus after mandibular third molar extraction helps us to evaluate and correlate the incidence of trismus with morphological and surgical factors that are associated with its incidence in the postoperative period. Patients referred to our institution for surgical removal of their impacted lower third molar between November 2014 and February 2015 were the participants of the study. Type of impaction, indication, and level of difficulty based on Pedersen criteria were obtained. Postoperative pain, swelling, and mouth opening (MO) limitations were evaluated at postoperative day (POD) 0, POD1, POD3, POD5, and POD7 and were analyzed. P < 0.05 was considered statistically significant. In this study, out of fifty patients, only nine patients had experienced limited MO during postoperative period when the duration of procedure exceeded 30 min. However, it occurred as cumulative of pericoronitis and tooth sectioning done. The postoperative trismus was more significant in disto-angular impaction ( P < 0.05) due to postoperative sequelae, swelling and pain.

Salvia somalensis essential oil as a potential cosmetic ingredient: solvent-free microwave extraction, hydrodistillation, GC-MS analysis, odour evaluation and in vitro cytotoxicity assays.

PubMed

Villa, C; Trucchi, B; Bertoli, A; Pistelli, L; Parodi, A; Bassi, A M; Ruffoni, B

2009-02-01

Salvia somalensis Vatke, a wild sage native of Somalia, has been studied with the aim of assessing the potential cosmetic application of its essential oil, recovered from fresh aerial parts by solvent-free microwave extraction - SFME. To evaluate the efficiency and reliability of this eco-friendly procedure, the recovery of the essential oil was also processed by conventional hydrodistillation (HD) and the results compared. The essential oils obtained by both SFME and HD were analysed by gas chromatography-mass spectrometry using apolar and polar capillary columns. The essential oil recovered by SFME was submitted to an odour evaluation that revealed peculiar olfactive characteristics interesting in alcoholic male perfumery and body detergents.In vitro cytotoxicity assays were carried out using NCTC 2544 human keratinocytes as target cells. The oil displayed slight cytotoxic effects, which were three orders of magnitude lower than those found for sodium dodecyl sulphate positive control. The promising results in terms of chemical composition, scent and safety seem to indicate this essential oil as an interesting potential functional ingredient useful in a cosmetic context.

Automated extraction of temporal motor activity signals from video recordings of neonatal seizures based on adaptive block matching.

PubMed

Karayiannis, Nicolaos B; Sami, Abdul; Frost, James D; Wise, Merrill S; Mizrahi, Eli M

2005-04-01

This paper presents an automated procedure developed to extract quantitative information from video recordings of neonatal seizures in the form of motor activity signals. This procedure relies on optical flow computation to select anatomical sites located on the infants' body parts. Motor activity signals are extracted by tracking selected anatomical sites during the seizure using adaptive block matching. A block of pixels is tracked throughout a sequence of frames by searching for the most similar block of pixels in subsequent frames; this search is facilitated by employing various update strategies to account for the changing appearance of the block. The proposed procedure is used to extract temporal motor activity signals from video recordings of neonatal seizures and other events not associated with seizures.

Magnetic navigation system for percutaneous coronary intervention

PubMed Central

Qi, Zhiyong; Wu, Bangwei; Luo, Xinping; Zhu, Jun; Shi, Haiming; Jin, Bo

2016-01-01

Abstract Background: Magnetic navigation system (MNS) allows calculation of the vessel coordinates in real space within the patient's chest for percutaneous coronary intervention (PCI). However, its impact on the procedural parameters and clinical outcomes is still a matter of debate. To derive a more precise estimation of the relationship, a meta-analysis was performed. Methods and Results: Studies exploring the advantages of MNS were identified in English-language articles by search of Medline, Web of Science, and Cochrane Library Databases (inception to October 2015). A standardized protocol was used to extract details on study design, region origin, demographic data, lesion type, and clinical outcomes. The main outcome measures were contrast consumption, procedural success rate, contrast used for wire crossing, procedure time to cross the lesions, and the fluoroscopy time fluoroscopy time. A total of 12 clinical trials involving 2174 patients were included for analysis (902 patients in the magnetic PCI group and 1272 in the conventional PCI group). Overall, contrast consumption was decreased by 40.45 mL (95% confidence interval [CI] −70.98 to −9.92, P = 0.009) in magnetic PCI group compared with control group. In addition, magnetic PCI was associated with significantly decreasing procedural time by 2.17 minutes (95% CI −3.91 to −0.44, P = 0.01) and the total fluoroscopy time was significantly decreased by 1.43 minutes (95% CI −2.29 to −0.57, P = 0.001) in magnetic PCI group. However, procedural success rate, contrast used for wire crossing, procedure time to cross the lesions, and the fluoroscopy time to cross the lesions demonstrated that no statistically difference was observed between 2 groups. Conclusion: The present meta-analysis indicated an improvement of overall contrast consumption, total procedural time, and fluoroscopy time in magnetic PCI group. However, no significant advantages were observed associated with procedural success rate. PMID:27442645

Magnetic navigation system for percutaneous coronary intervention: A meta-analysis.

PubMed

Qi, Zhiyong; Wu, Bangwei; Luo, Xinping; Zhu, Jun; Shi, Haiming; Jin, Bo

2016-07-01

Magnetic navigation system (MNS) allows calculation of the vessel coordinates in real space within the patient's chest for percutaneous coronary intervention (PCI). However, its impact on the procedural parameters and clinical outcomes is still a matter of debate. To derive a more precise estimation of the relationship, a meta-analysis was performed. Studies exploring the advantages of MNS were identified in English-language articles by search of Medline, Web of Science, and Cochrane Library Databases (inception to October 2015). A standardized protocol was used to extract details on study design, region origin, demographic data, lesion type, and clinical outcomes. The main outcome measures were contrast consumption, procedural success rate, contrast used for wire crossing, procedure time to cross the lesions, and the fluoroscopy time fluoroscopy time. A total of 12 clinical trials involving 2174 patients were included for analysis (902 patients in the magnetic PCI group and 1272 in the conventional PCI group). Overall, contrast consumption was decreased by 40.45 mL (95% confidence interval [CI] -70.98 to -9.92, P = 0.009) in magnetic PCI group compared with control group. In addition, magnetic PCI was associated with significantly decreasing procedural time by 2.17 minutes (95% CI -3.91 to -0.44, P = 0.01) and the total fluoroscopy time was significantly decreased by 1.43 minutes (95% CI -2.29 to -0.57, P = 0.001) in magnetic PCI group. However, procedural success rate, contrast used for wire crossing, procedure time to cross the lesions, and the fluoroscopy time to cross the lesions demonstrated that no statistically difference was observed between 2 groups. The present meta-analysis indicated an improvement of overall contrast consumption, total procedural time, and fluoroscopy time in magnetic PCI group. However, no significant advantages were observed associated with procedural success rate.

Guide to Black Politics 1976, Part II: The Republican National Convention, Kansas City, Missouri, August 16-19, 1976.

ERIC Educational Resources Information Center

Joint Center for Political Studies, Washington, DC.

This guide was designed to assist black delegates attending the 1976 Republican National Convention. The guide is divided into four main parts. The first part contains information on convention procedures, convention committees, and various aspects of black participation in politics. The second and third parts include the names of delegates to the…

The automatic extraction of pitch perturbation using microcomputers: some methodological considerations.

PubMed

Deem, J F; Manning, W H; Knack, J V; Matesich, J S

1989-09-01

A program for the automatic extraction of jitter (PAEJ) was developed for the clinical measurement of pitch perturbations using a microcomputer. The program currently includes 12 implementations of an algorithm for marking the boundary criteria for a fundamental period of vocal fold vibration. The relative sensitivity of these extraction procedures for identifying the pitch period was compared using sine waves. Data obtained to date provide information for each procedure concerning the effects of waveform peakedness and slope, sample duration in cycles, noise level of the analysis system with both direct and tape recorded input, and the influence of interpolation. Zero crossing extraction procedures provided lower jitter values regardless of sine wave frequency or sample duration. The procedures making use of positive- or negative-going zero crossings with interpolation provided the lowest measures of jitter with the sine wave stimuli. Pilot data obtained with normal-speaking adults indicated that jitter measures varied as a function of the speaker, vowel, and sample duration.

Sensitive trace enrichment of environmental andiandrogen vinclozolin from natural waters and sediment samples using hollow-fiber liquid-phase microextraction.

PubMed

Lambropoulou, Dimitra A; Albanis, Triantafyllos A

2004-12-17

The presence of vinclozolin in the environment as far as the endocrine disruption effects in biota are concerned has raised interest in the environmental fate of this compound. In this respect, the present study attempts to investigate the feasibility of applying a novel quantitative method, liquid-phase microextraction (LPME), so as to determine this environmental andiandrogen in environmental samples such as water and sediment samples. The technique involved the use of a small amount (3 microL) of organic solvent impregnated in a hollow fiber membrane, which was attached to the needle of a conventional GC syringe. The extracted samples were analyzed by gas chromatography coupled with electron-capture detection. Experimental LPME conditions such as extraction solvent, stirring rate, content of NaCl and pH were tested. Once LPME was optimized, the performance of the proposed technique was evaluated for the determination of vinclozolin in different types of natural water samples. The recovery of spiked water samples was from 80 to 99%. The procedure was adequate for quantification of vinclozolin in waters at levels of 0.010 to 50 microg/L (r> 0.994) with a detection limit of 0.001 microg/L (S/N= 3). Natural sediment samples from the Aliakmonas River area (Macedonia, Greece) spiked with the target andiandrogen compound were liquid-liquid extracted and analyzed by the methodology developed in this work. No significant interferences from the samples matrix were noticed, indicating that the reported methodology is an innovative tactic for sample preparation in sediment analysis, with a considerable improvement in the achieved detection limits. The results demonstrated that apart from analyte enrichment, the proposed LPME procedure also serves as clean-up method and could be successfully performed to determine trace amounts of vinclozolin in water and sediment samples.

Method 1664: N-hexane extractable material (hem) and silica gel treated n-hexane extractable material (SGT-HEM) by extraction and gravimetry (oil and grease and total petroleum hydrocarbons), April 1995

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

NONE

Method 1664 was developed by the United States Environmental Protection Agency Office of Science and Technology to replace previously used gravimetric procedures that employed Freon-113, a Class I CFC, as the extraction solvent for the determination of oil and grease and petroleum hydrocarbons. Method 1664 is a performance-based method applicable to aqueous matrices that requires the use of n-hexane as the extraction solvent and gravimetry as the determinative technique. In addition, QC procedures designed to monitor precision and accuracy have been incorporated into Method 1664.

Development of an analytical procedure to study linear alkylbenzenesulphonate (LAS) degradation in sewage sludge-amended soils.

PubMed

Comellas, L; Portillo, J L; Vaquero, M T

1993-12-24

A procedure for determining linear alkylbenzenesulphonates (LASs) in sewage sludge and amended soils has been developed. Extraction by sample treatment with 0.5 M potassium hydroxide in methanol and reflux was compared with a previously described extraction procedure in Soxhlet with methanol and solid sodium hydroxide in the sample. Repeatability results were similar with savings in extraction time, solvents and evaporation time. A clean-up method involving a C18 cartridge has been developed. Analytes were quantified by a reversed-phase HPLC method with UV and fluorescence detectors. Recoveries obtained were higher than 84%. The standing procedure was applied to high doses of sewage sludge-amended soils (15%) with increasing quantities of added LASs. Degradation data for a 116-day period are presented.

Comparison of intracorporeal single-stapled and double-stapled anastomosis in laparoscopic low anterior resection for rectal cancer: a case-control study.

PubMed

Kim, Hye Jin; Choi, Gyu-Seog; Park, Jun Seok; Park, Soo Yeun

2013-01-01

Recently, a single-stapled technique (SST) was performed instead of the conventional double-stapled technique (DST) in laparoscopic low anterior resection for anastomosis, by placement of intracorporeal purse-string sutures on the distal rectum with transanal specimen extraction. This study aimed to compare the short-term outcomes between the two anastomotic techniques. Between July 2007 and April 2010, 60 patients underwent SST by laparoscopic or robotic procedure. These patients were matched 1:2 by age, gender, date of surgery, and tumor stage with 120 patients who underwent conventional DST in laparoscopic low anterior resection. The robotic-assisted operative approach was used more frequently in the SST group than in the DST group (61.7 % vs. 3.3 %, p < 0.001). The mean operative time was 203.9 (range, 120-400) min for the SST group and 167.6 (range, 90-300) min for the DST group (p < 0.001). For specimen removal, the transanal approach was used in the SST group, while the transabdominal approach was used for the DST group. The pain score (visual analogue scale) of the SST group was lower (4.5 vs. 5.6, p < 0.001), although postoperative recovery was similar. Pathological examination revealed that the distal resection margin was significantly longer in the SST group (3.1 vs. 2.5 cm, p = 0.018). Postoperative morbidity including anastomotic leakage was similar in both groups. SST yielded equivalent short-term outcomes when compared to conventional DST and provided the advantages of minimal access and a longer distal resection margin. Therefore, SST in lower anterior resection may be a useful alternative to conventional DST.

Comparison of Tooth Color Change After Bleaching With Conventional and Different Light-Activated Methods.

PubMed

Shahabi, Sima; Assadian, Hadi; Mahmoudi Nahavandi, Alireza; Nokhbatolfoghahaei, Hanieh

2018-01-01

Introduction: The demand for esthetic dental treatments is increasing in recent years mainly due to improved oral hygiene and better maintenance of oral health and teeth in older individuals. Bleaching of discolored anterior teeth is the most popular among esthetic dental treatments. Even individuals with sound teeth and adequate esthetics seek to have whiter teeth in the anterior region. The aim of this study was to evaluate tooth color changes following conventional in-office bleaching techniques compared to light-activated methods using different light sources. Methods: Seventy sound anterior teeth (devoided of caries and/or fracture), extracted for periodontal and orthodontic reasons were selected and allocated to 7 groups: (A) control, (B) conventional bleaching (C) LED-activated bleaching, (D) KTP laser-activated bleaching, (E) diode laser-activated bleaching, (F) Nd:YAG laser-activated bleaching and (G) CO2 laser-activated bleaching. Colorimetric evaluation was carried out before and after treatment using a spectrophotoradiometer. Data were analyzed by one- and two-way analysis of variance (ANOVA) as well as multiple comparison methods. Results: The results showed that all bleaching procedures were effective in reducing the yellowness index. However, the KTP laser-activated bleaching was significantly more effective than the other techniques in 95% confidence level. It was also seen that CO2 laser activated method has outperformed groups E, F and G and the conventional bleaching without light activation was not effective at all and represented similar results with the control group. Furthermore, the groups E and G had almost the same results in decreasing the yellowness index. Conclusion: The results showed that all bleaching techniques were effective however, the KTP laser-activated bleaching was significantly more efficient, closely followed by the CO2 laser-activated bleaching technique.

Clean-up of aqueous acetone vegetable extracts by solid-matrix partition for pyrethroid residue determination by gas chromatography-electron-capture detection.

PubMed

Di Muccio, A; Barbini, D A; Generali, T; Pelosi, P; Ausili, A; Vergori, F; Camoni, I

1997-03-21

Disposable, ready-to-use cartridges filled with macroporous diatomaceous material are used to carry out a partition clean-up that, in a single step, is capable of transferring pesticide residues from aqueous acetone extracts into light petroleum-dichloromethane (75:25, v/v). This procedure takes the place of some functions (such as separatory-funnel partition, drying over anhydrous sodium sulphate and partial adsorption clean-up) usually performed by separate steps in classical schemes. Fourteen pyrethroid pesticides, including tefluthrin, tetramethrin, cyphenothrin, cyfluthrin, flucythrinate, tau-fluvalinate, deltamethrin, bioallethrin, fenpropathrin, lambda-cyhalothrin, permethrin, alpha-cypermethrin, esfenvalerate and tralomethrin were determined using the described procedure with satisfactory recoveries for most of them, at spiking levels ranging from 0.08 to 0.82 mg/kg for the different compounds. Crops subjected to the described procedure included strawberry, apple, and orange gave extracts containing a mass of co-extractives that was between 5 and 30 mg. Compared with classical schemes, the described procedure is simple, less labour intensive, allows parallel handling of several extracts and does not require the preparation and maintenance of equipment. Troublesome emulsions such as those frequently observed in separation funnel partitioning do not occur.

Comparison of procedure coding systems for level 1 and 2 hospitals in South Africa.

PubMed

Montewa, Lebogang; Hanmer, Lyn; Reagon, Gavin

2013-01-01

The ability of three procedure coding systems to reflect the procedure concepts extracted from patient records from six hospitals was compared, in order to inform decision making about a procedure coding standard for South Africa. A convenience sample of 126 procedure concepts was extracted from patient records at three level 1 hospitals and three level 2 hospitals. Each procedure concept was coded using ICPC-2, ICD-9-CM, and CCSA-2001. The extent to which each code assigned actually reflected the procedure concept was evaluated (between 'no match' and 'complete match'). For the study sample, CCSA-2001 was found to reflect the procedure concepts most completely, followed by ICD-9-CM and then ICPC-2. In practice, decision making about procedure coding standards would depend on multiple factors in addition to coding accuracy.

Birch pollinosis and atopy caused by apple, peach, and hazelnut; comparison of three extraction procedures with two apple strains.

PubMed

de Groot, H; de Jong, N W; Vuijk, M H; Gerth van Wijk, R

1996-10-01

This study aimed, first, to study the prevalence in The Netherlands of atopy caused by apple, peach, and hazelnut in patients with tree pollinosis, and, second, to compare three extraction procedures for skin prick testing with two different apple strains. Skin prick tests and RAST were performed on 79 consecutive patients with tree pollinosis, visiting the department of allergology during spring 1995. In skin prick tests, we used three different extracts (juice, freeze-dried extract, and low-temperature acetone powder extract) of two apple strains, Golden Delicious and Granny Smith. Case histories for apple, peach, and hazelnut were positive in 35 (44.3%), 23 (29%), and 35 (44.3%) patients, respectively. More than two-thirds of the patients had symptoms characteristic of oral allergy syndrome. Skin prick tests for apple, peach, and hazelnut were positive in 51 (64.6%), 61 (77.2%), and 71 (89.9%) patients, respectively. Granny Smith showed more positive skin reactions and a better agreement with clinical history than Golden Delicious, and juice was superior to the two other extraction procedures for both apple strains. RAST for apple, peach, and hazelnut was positive in 53 (68.8%), 13 (16.9%), and 31 (40.3%) patients, respectively. Concordance between skin prick test and case history was found in 77%, 52%, and 54%, for apple, peach, and hazelnut, respectively. We found a high percentage of concurrence of clinical allergy to birch pollen and apple, peach, and hazelnut, confirmed by both skin prick testing and RAST. Approximately half of these patients had symptoms (especially oral allergy syndrome) after eating these products. We also found an easy extraction procedure (juice extract) suitable for apple skin prick testing, superior even to freeze-dried extraction or the low-temperature acetone powder technique.

Crew Procedures for Continuous Descent Arrivals Using Conventional Guidance

NASA Technical Reports Server (NTRS)

Oseguera-Lohr, Rosa M.; Williams, David H.; Lewis, Elliot T,

2007-01-01

This paper presents results from a simulation study which investigated the use of Continuous Descent Arrival (CDA) procedures for conducting a descent through a busy terminal area, using conventional transport-category automation. This research was part of the Low Noise Flight Procedures (LNFP) element within the Quiet Aircraft Technology (QAT) Project, that addressed development of flight guidance, and supporting pilot and Air Traffic Control (ATC) procedures for low noise operations. The procedures and chart were designed to be easy to understand, and to make it easy for the crew to make changes via the Flight Management Computer Control-Display Unit (FMC-CDU) to accommodate changes from ATC. The test runs were intended to represent situations typical of what exists in many of today's terminal areas, including interruptions to the descent in the form of clearances issued by ATC.

Digital image processing and analysis for activated sludge wastewater treatment.

PubMed

Khan, Muhammad Burhan; Lee, Xue Yong; Nisar, Humaira; Ng, Choon Aun; Yeap, Kim Ho; Malik, Aamir Saeed

2015-01-01

Activated sludge system is generally used in wastewater treatment plants for processing domestic influent. Conventionally the activated sludge wastewater treatment is monitored by measuring physico-chemical parameters like total suspended solids (TSSol), sludge volume index (SVI) and chemical oxygen demand (COD) etc. For the measurement, tests are conducted in the laboratory, which take many hours to give the final measurement. Digital image processing and analysis offers a better alternative not only to monitor and characterize the current state of activated sludge but also to predict the future state. The characterization by image processing and analysis is done by correlating the time evolution of parameters extracted by image analysis of floc and filaments with the physico-chemical parameters. This chapter briefly reviews the activated sludge wastewater treatment; and, procedures of image acquisition, preprocessing, segmentation and analysis in the specific context of activated sludge wastewater treatment. In the latter part additional procedures like z-stacking, image stitching are introduced for wastewater image preprocessing, which are not previously used in the context of activated sludge. Different preprocessing and segmentation techniques are proposed, along with the survey of imaging procedures reported in the literature. Finally the image analysis based morphological parameters and correlation of the parameters with regard to monitoring and prediction of activated sludge are discussed. Hence it is observed that image analysis can play a very useful role in the monitoring of activated sludge wastewater treatment plants.

Landsat TM data processing for lithological discrimination in the Caraculo area (Namibe Province, SW Angola)

NASA Astrophysics Data System (ADS)

Alberti, A.; Alessandro, V.; Pieruccini, U.; Pranzini, E.

1993-10-01

Landsat TM data were used for lithological discrimination and mapping in the little-known, semiarid 900 km 2 area around Caraculo station and the middle course of the Rio Giraul (Namibe Province, SW Angola) following two main procedures. The first of these was based on visual evaluation of three-band composites, band-ratio composites and Principal Component Analysis. The second method relied on the extraction of spectral signatures, and their use to obtain automatic classifications. Satisfactory results were reached with the first procedure, thus allowing - with limited support of ground information — the draft of a lithological map, while the second method was not systematically efficient, even for confirmation of data acquired with the first procedure. Image interpretation suggests that an extensive but hithertoun differentiated metasedimentary complex consisting of a heterogeneous supracrustal sequence should be subdivided into at least two units. Field observations proved that one of these is marked by a notable frequency of marbles and the other is characterized by a widespread occurrence of amphibolitic bodies. Moreover, a belt of undetermined (thermally metamorphosed ?) metamorphic rocks is interposed between them. The distinction of so far unidentified units, though restricted to interpretation of processed Landsat TM data, has significant geological implications also in the regional context and will be helpful in guiding future work with conventional geological methods.

Conventional versus traction-assisted endoscopic submucosal dissection for gastric neoplasms: a multicenter, randomized controlled trial (with video).

PubMed

Yoshida, Masao; Takizawa, Kohei; Suzuki, Sho; Koike, Yoshiki; Nonaka, Satoru; Yamasaki, Yasushi; Minagawa, Takeyoshi; Sato, Chiko; Takeuchi, Chihiro; Watanabe, Ko; Kanzaki, Hiromitsu; Morimoto, Hiroyuki; Yano, Takafumi; Sudo, Kosuke; Mori, Keita; Gotoda, Takuji; Ono, Hiroyuki

2018-05-01

The aim of this study was to clarify whether dental floss clip (DFC) traction improves the technical outcomes of endoscopic submucosal dissection (ESD). A superiority, randomized control trial was conducted at 14 institutions across Japan. Patients with single gastric neoplasm meeting the indications of the Japanese guidelines for gastric treatment were enrolled and assigned to receive conventional ESD or DFC traction-assisted ESD (DFC-ESD). Randomization was performed according to a computer-generated random sequence with stratification by institution, tumor location, tumor size, and operator experience. The primary endpoint was ESD procedure time, defined as the time from the start of the submucosal injection to the end of the tumor removal procedure. Between July 2015 and September 2016, 640 patients underwent randomization. Of these, 316 patients who underwent conventional ESD and 319 patients who underwent DFC-ESD were included in our analysis. The mean ESD procedure time was 60.7 and 58.1 minutes for conventional ESD and DFC-ESD, respectively (P = .45). Perforation was less frequent in the DFC-ESD group (2.2% vs .3%, P = .04). For lesions located in the greater curvature of the upper or middle stomach, the mean procedure time was significantly shorter in the DFC-ESD group (104.1 vs 57.2 minutes, P = .01). Our findings suggest that DFC-ESD does not result in shorter procedure time in the overall patient population, but it can reduce the risk of perforation. When selectively applied to lesions located in the greater curvature of the upper or middle stomach, DFC-ESD provides a remarkable reduction in procedure time. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Comparison of machine learned approaches for thyroid nodule characterization from shear wave elastography images

NASA Astrophysics Data System (ADS)

Pereira, Carina; Dighe, Manjiri; Alessio, Adam M.

2018-02-01

Various Computer Aided Diagnosis (CAD) systems have been developed that characterize thyroid nodules using the features extracted from the B-mode ultrasound images and Shear Wave Elastography images (SWE). These features, however, are not perfect predictors of malignancy. In other domains, deep learning techniques such as Convolutional Neural Networks (CNNs) have outperformed conventional feature extraction based machine learning approaches. In general, fully trained CNNs require substantial volumes of data, motivating several efforts to use transfer learning with pre-trained CNNs. In this context, we sought to compare the performance of conventional feature extraction, fully trained CNNs, and transfer learning based, pre-trained CNNs for the detection of thyroid malignancy from ultrasound images. We compared these approaches applied to a data set of 964 B-mode and SWE images from 165 patients. The data were divided into 80% training/validation and 20% testing data. The highest accuracies achieved on the testing data for the conventional feature extraction, fully trained CNN, and pre-trained CNN were 0.80, 0.75, and 0.83 respectively. In this application, classification using a pre-trained network yielded the best performance, potentially due to the relatively limited sample size and sub-optimal architecture for the fully trained CNN.

Development of extraction procedure for determination of mercury species using SPME-assisted dispersive derivative agent

NASA Astrophysics Data System (ADS)

Abdullah, Md Pauzi; Khalik, Wan Mohd Afiq Wan Mohd; Othman, Mohamed Rozali

2016-11-01

The extraction procedure for determination of low level mercury using solid phase microextraction was successfully carried out. Design of experimental works using factorial design and central composite design were applied to screen and predict the optimum condition for extraction step. In this study, variables namely concentration level (5 % m/v) and volume of derivatization solution (150 µL) has depicted as main effect for controlling the suitability of derivative reagent condition. Maximum of signal response (account as total peak areas for mercury species) was obtained when extraction procedure was set up at pH of water sample (5.8), extraction time (14 min), extraction temperature (43 °C) and stirring rate (450 rpm). Reducing time required to reach equilibrium is new improvement achieved in this study. Detection limit for each species (MeHg 26.17 ngL-1; EtHg 48.84 ngL-1 and IHg 14.11 ngL-1) was calculated lower than our previous work. Recovery, repeatability and reproducibility trial were recorded varied at acceptable range and relative standard deviation was calculated below than 10 %.

Extraction of vitexin from binahong (Anredera cordifolia (Ten.) Steenis) leaves using betaine - 1,4 butanediol natural deep eutectic solvent (NADES)

NASA Astrophysics Data System (ADS)

Mulia, Kamarza; Muhammad, Fajri; Krisanti, Elsa

2017-03-01

The leaves of binahong (Anredera cordifolia (Ten) Steenis) contain flavonoids as bioactive substances that have efficacy to treat wounds and diseases caused by bacteria. One of the flavonoids contained in the leaves is 8-glucopyranosyl-4'5'7-trihydroxyflavone or vitexin. Conventional extraction of flavonoids from leaves of binahong has been developed and usually using non-friendly organic solvent. To overcome these problems, a Natural Deep Eutectic Solvent (NADES) is used to replace the conventional organic solvents, as it is an environmentally friendly, non-toxic and high boiling point solvent. In this study, a betaine-based NADES combined with 1,4-butanediol in 1:3 mole ratio was used as the extraction solvent. Vitexin in the extract was analyzed qualitatively and quantitatively using an HPLC. The extraction of vitexin from binahong leaves at room temperature (27 °C) for four hours give yield of 46 ppm, much lower than 200 ppm yield obtained after extraction at 55 °C for 90 minutes. This results showed that (a) NADES consisting of betaine and 1,4 butanediol is a promising green solvent for extraction of vitexin from binahong leaves, and, (b) the extraction can be performed above ambient temperature, as long as it does not exceed the degradation temperature of the bioactive compound extracted.

A clinical evaluation of comprehensive dental treatment for children under general anesthesia.

PubMed

Su, H L; Chen, P S

1992-12-01

The purpose of this study is to evaluate the comprehensive dental treatment for children under general anesthesia. From 1989 to 1991, 57 children with mean age of 3 years 2 months were treated, followed up with a minimal of 1 year. This procedure allows the dentition to be restored in one visit. Further care including preventive options and behavior shaping was provided on a 3-6 months recall schedule. The reasons for general anesthesia are that these children were either unable to accept treatment because of handicaps, extreme fear or young age. Their mean number of decayed tooth was 15 (Standard Deviation, SD = 5) and nearly three quarters of the children were under 6 years old. The most frequent treatment procedures were the extraction of teeth, composite resin restoration and Ni-Cr crown restoration. The Ni-Cr crown (1.7% failure rate) was more successful than the amalgam and composite resin restoration (9.7% failure rate). Pedo-strip crown had the highest failure rate (22%) for anterior teeth restoration. Nineteen children needed retreatment with conventional behavior guide. Six children had new caries and required further treatment. Thirty eight children returned for regular recall during the minimal 1 year follow-up period.

On the BRST Quantization of the Massless Bosonic Particle in Twistor-Like Formulation

NASA Astrophysics Data System (ADS)

Bandos, Igor; Maznytsia, Alexey; Rudychev, Igor; Sorokin, Dmitri

We study some features of bosonic-particle path-integral quantization in a twistor-like approach by the use of the BRST-BFV-quantization prescription. In the course of the Hamiltonian analysis we observe links between various formulations of the twistor-like particle by performing a conversion of the Hamiltonian constraints of one formulation to another. A particular feature of the conversion procedure applied to turn the second-class constraints into first-class constraints is that the simplest Lorentz-covariant way to do this is to convert a full mixed set of the initial first- and second-class constraints rather than explicitly extracting and converting only the second-class constraints. Another novel feature of the conversion procedure applied below is that in the case of the D = 4 and D = 6 twistor-like particle the number of new auxiliary Lorentz-covariant coordinates, which one introduces to get a system of first-class constraints in an extended phase space, exceeds the number of independent second-class constraints of the original dynamical system. We calculate the twistor-like particle propagator in D = 3,4,6 space-time dimensions and show that it coincides with that of a conventional massless bosonic particle.

Laser versus scalpel cleaning of crustose lichens on granite

NASA Astrophysics Data System (ADS)

Rivas, T.; Pozo-Antonio, J. S.; López de Silanes, M. E.; Ramil, A.; López, A. J.

2018-05-01

This paper addresses the evaluation of the cleaning of crustose lichens developing on granite. The evaluation was performed considering the effectiveness of the cleanings and harmfulness exerted on the granite. The laser cleaning of lichen was compared with the most conventional procedure, scalpel. The combination of both procedures was also tested. The study, which was carried out with two different species of crustose lichen, was also focused on the influence of the intrinsic characteristics of the lichen on the effectiveness. The cleanings were evaluated by optic and electronic microscopies, FTIR and colour spectrophotometry. A previous characterization of the lichen and its interaction with the granite using those analytical techniques were also performed. The laser cleaning effectiveness depends on the coverage and the colour of the lichen; also, the prior mechanical weakening of the lichen by scalpel seemed to improve the laser cleaning. The darkest lichen was satisfactorily removed by laser and with the combined cleaning. Conversely, the lightest lichen was more difficult to extract with laser than the darkest lichen, being necessary to apply both methods sequentially. Despite laser and the combination of methods cleaned satisfactorily the surface, they were unable to eliminate the thalli into fissures.

Context-Based Urban Terrain Reconstruction from Uav-Videos for Geoinformation Applications

NASA Astrophysics Data System (ADS)

Bulatov, D.; Solbrig, P.; Gross, H.; Wernerus, P.; Repasi, E.; Heipke, C.

2011-09-01

Urban terrain reconstruction has many applications in areas of civil engineering, urban planning, surveillance and defense research. Therefore the needs of covering ad-hoc demand and performing a close-range urban terrain reconstruction with miniaturized and relatively inexpensive sensor platforms are constantly growing. Using (miniaturized) unmanned aerial vehicles, (M)UAVs, represents one of the most attractive alternatives to conventional large-scale aerial imagery. We cover in this paper a four-step procedure of obtaining georeferenced 3D urban models from video sequences. The four steps of the procedure - orientation, dense reconstruction, urban terrain modeling and geo-referencing - are robust, straight-forward, and nearly fully-automatic. The two last steps - namely, urban terrain modeling from almost-nadir videos and co-registration of models 6ndash; represent the main contribution of this work and will therefore be covered with more detail. The essential substeps of the third step include digital terrain model (DTM) extraction, segregation of buildings from vegetation, as well as instantiation of building and tree models. The last step is subdivided into quasi- intrasensorial registration of Euclidean reconstructions and intersensorial registration with a geo-referenced orthophoto. Finally, we present reconstruction results from a real data-set and outline ideas for future work.

Glacier surface velocity estimation in the West Kunlun Mountain range from L-band ALOS/PALSAR images using modified synthetic aperture radar offset-tracking procedure

NASA Astrophysics Data System (ADS)

Ruan, Zhixing; Guo, Huadong; Liu, Guang; Yan, Shiyong

2014-01-01

Glacier movement is closely related to changes in climatic, hydrological, and geological factors. However, detecting glacier surface flow velocity with conventional ground surveys is challenging. Remote sensing techniques, especially synthetic aperture radar (SAR), provide regular observations covering larger-scale glacier regions. Glacier surface flow velocity in the West Kunlun Mountains using modified offset-tracking techniques based on ALOS/PALSAR images is estimated. Three maps of glacier flow velocity for the period 2007 to 2010 are derived from procedures of offset detection using cross correlation in the Fourier domain and global offset elimination of thin plate smooth splines. Our results indicate that, on average, winter glacier motion on the North Slope is 1 cm/day faster than on the South Slope-a result which corresponds well with the local topography. The performance of our method as regards the reliability of extracted displacements and the robustness of this algorithm are discussed. The SAR-based offset tracking is proven to be reliable and robust, making it possible to investigate comprehensive glacier movement and its response mechanism to environmental change.

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...

Optimizing the extraction, storage, and analysis of airborne endotoxins

USDA-ARS?s Scientific Manuscript database

While the Limulus amebocyte lysate (LAL) assay is part of most procedures to assess airborne endotoxin exposure, there is no universally agreed upon standard procedure. The purpose of this study was to fill in additional knowledge gaps with respect to the extraction, storage, and analysis of endotox...

Surgical and social implications of extraction of mandibular third molars as a separate procedure before bilateral sagittal split osteotomy.

PubMed

Morton, L; Downie, I

2017-11-01

In some units, lower wisdom teeth are extracted in a separate procedure before bilateral sagittal split osteotomy (BSSO), whereas in others they are removed at the time of the osteotomy. We identified 57 patients who had BSSO at Salisbury Hospital between October 2013 and September 2015, 40 of whom had their wisdom teeth extracted at the same time. The remaining 17 did not have wisdom teeth. Patients who have these teeth extracted as a separate procedure require at least one day off work, which can result in a loss of earnings. Our findings showed that the removal of third molars at the time of orthognathic surgery has considerable social and financial benefits, and does not increase the risk of morbidity. Copyright © 2017. Published by Elsevier Ltd.

A comparison of recovery of virus from wastewaters by beef extract-Celite, ferric chloride, and filter concentration procedures.

PubMed

Dahling, D R; Wright, B A

1988-12-01

An improved concentration method using sample volumes as large as 1500 ml has been developed to monitor for viruses in wastewaters. Non-precipitating dry beef extract powder is added to wastewater samples to give a 3% concentration and mixed until dissolved. This is followed by the addition of Celite as a virus adsorbent. By manipulating pH, viruses are eluted from the Celite in small volumes of phosphate buffer. This procedure was further tested without the aid of the Celite additives using a precipitating beef extract powder and substituting FeCl3 as an alternate reagent for the Celite. Comparison testing was also made with the currently recommended cartridge and disc filter procedures. In all cases, the non-precipitating beef extract-Celite method gave higher recovery rates in highly polluted waters.

Double-label immunofluorescence method for simultaneous detection of adenovirus and herpes simplex virus from the eye.

PubMed

Walpita, P; Darougar, S

1989-07-01

The development and application of a double-label immunofluorescence method which has the potential to screen for single or dual infections from any site, in single shell vial cultures, is described. In this study, a total of 1,141 ocular specimens were inoculated in shell vials, centrifuged at 15,000 X g for 1 h, incubated at 37 degrees C for 48 h, and fixed in methanol at room temperature for 15 min. The virus inclusions were detected by staining with a double-label indirect immunofluorescence procedure using mixtures of appropriate first antibodies, followed by fluorescein- and rhodamine-conjugated second antibodies. Each specimen was also inoculated in parallel by the conventional virus isolation method. The sensitivity and specificity of the double-label shell vial procedure were comparable to those with the conventional method, and the former test took only 48 h to complete. The test offers a rapid and simple single-vial procedure which allows for individual or simultaneous detection of multiple pathogens. It results in savings in time and cost over the conventional virus isolation method and other shell vial procedures.

Single-site multiport combined splenectomy and cholecystectomy with conventional laparoscopic instruments: Case series and review of literature

PubMed Central

Ozemir, Ibrahim Ali; Bayraktar, Baris; Bayraktar, Onur; Tosun, Salih; Bilgic, Cagri; Demiral, Gokhan; Ozturk, Erman; Yigitbasi, Rafet; Alimoglu, Orhan

2015-01-01

Introduction Conventional laparoscopic procedures have been used for splenic diseases and concomitant gallbladder stones, frequently in patients with hereditary spherocytosis since 1990’s. The aim of this study is to evaluate the feasibility of single-site surgery with conventional instruments in combined procedures. Presentation of case series Six consecutive patients who scheduled for combined cholecystectomy and splenectomy because of hereditary spherocytosis or autoimmune hemolytic anemia were included this study. Both procedures were performed via trans-umbilical single-site multiport approach using conventional instruments. All procedures completed successfully without conversion to open surgery or conventional laparoscopic surgery. An additional trocar was required for only one patient. The mean operation time was 190 min (150–275 min). The mean blood loss was 185 ml (70–300 ml). Median postoperative hospital stay was two days. No perioperative mortality or major complications occurred in our series. Recurrent anemia, hernia formation or wound infection was not observed during the follow-up period. Discussion Nowadays, publications are arising about laparoscopic or single site surgery for combined diseases. Surgery for combined diseases has some difficulties owing to the placement of organs and position of the patient during laparoscopic surgery. Single site laparoscopic surgery has been proposed to have better cosmetic outcome, less postoperative pain, greater patient satisfaction and faster recovery compared to standard laparoscopy. Conclusion We consider that single-site multiport laparoscopic approach for combined splenectomy and cholecystectomy is a safe and feasible technique, after gaining enough experience on single site surgery. PMID:26708949

Insights into Comparative Antimicrobial Efficacies of Synthetic and Organic Agents: The Case of ZnS Nanoparticles and Zingiber officinale Rosc.

NASA Astrophysics Data System (ADS)

Obidi, O. F.; Nejo, A. O.; Ayeni, R. A.; Revaprasadu, N.

2018-03-01

The differences among the antimicrobial activities of synthetic nanoparticles (NPs), organic agents and conventional antibiotics against human pathogens are little known. We compared the antimicrobial activities of aqueous, ethanol and ethyl acetate extracts of Zingiber officinale rhizomes with ZnS NPs and tetracycline/nystatin using agar-diffusion techniques. Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and ultraviolet spectroscopy were used to characterize ZnS NPs. At 100 mg/ml, ethanol and ethyl acetate extract inhibited Acinetobacter baumannii, Salmonella typhimurium, Enterococcus faecium, Shigella flexneri, Klebsiella pneumoniae, Staphylococcus epidermidis and Candida albicans with zones of inhibition (ZOI) ranging between 0-42 mm and 0-39 mm, respectively. Candida albicans had a remarkable ZOI of 42 mm and 22 mm from ethanol and ZnS NPs compared with 20 mm from conventional nystatin. TEM and FTIR revealed spherically shaped polydispersed NPs with particle size of 12.5 nm and the role of banana peel extracts in ZnS NPs synthesis. Organic and synthetic NPs proved potential alternatives to conventional antimicrobial agents.

An investigation of paper based microfluidic devices for size based separation and extraction applications.

PubMed

Zhong, Z W; Wu, R G; Wang, Z P; Tan, H L

2015-09-01

Conventional microfluidic devices are typically complex and expensive. The devices require the use of pneumatic control systems or highly precise pumps to control the flow in the devices. This work investigates an alternative method using paper based microfluidic devices to replace conventional microfluidic devices. Size based separation and extraction experiments conducted were able to separate free dye from a mixed protein and dye solution. Experimental results showed that pure fluorescein isothiocyanate could be separated from a solution of mixed fluorescein isothiocyanate and fluorescein isothiocyanate labeled bovine serum albumin. The analysis readings obtained from a spectrophotometer clearly show that the extracted tartrazine sample did not contain any amount of Blue-BSA, because its absorbance value was 0.000 measured at a wavelength of 590nm, which correlated to Blue-BSA. These demonstrate that paper based microfluidic devices, which are inexpensive and easy to implement, can potentially replace their conventional counterparts by the use of simple geometry designs and the capillary action. These findings will potentially help in future developments of paper based microfluidic devices. Copyright © 2015 Elsevier B.V. All rights reserved.

Insights into Comparative Antimicrobial Efficacies of Synthetic and Organic Agents: The Case of ZnS Nanoparticles and Zingiber officinale Rosc.

NASA Astrophysics Data System (ADS)

Obidi, O. F.; Nejo, A. O.; Ayeni, R. A.; Revaprasadu, N.

2018-06-01

The differences among the antimicrobial activities of synthetic nanoparticles (NPs), organic agents and conventional antibiotics against human pathogens are little known. We compared the antimicrobial activities of aqueous, ethanol and ethyl acetate extracts of Zingiber officinale rhizomes with ZnS NPs and tetracycline/nystatin using agar-diffusion techniques. Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and ultraviolet spectroscopy were used to characterize ZnS NPs. At 100 mg/ml, ethanol and ethyl acetate extract inhibited Acinetobacter baumannii, Salmonella typhimurium, Enterococcus faecium, Shigella flexneri, Klebsiella pneumoniae, Staphylococcus epidermidis and Candida albicans with zones of inhibition (ZOI) ranging between 0-42 mm and 0-39 mm, respectively. Candida albicans had a remarkable ZOI of 42 mm and 22 mm from ethanol and ZnS NPs compared with 20 mm from conventional nystatin. TEM and FTIR revealed spherically shaped polydispersed NPs with particle size of 12.5 nm and the role of banana peel extracts in ZnS NPs synthesis. Organic and synthetic NPs proved potential alternatives to conventional antimicrobial agents.

Thermal effusivity measurement of conventional and organic coffee oils via photopyroelectric technique.

PubMed

Bedoya, A; Gordillo-Delgado, F; Cruz-Santillana, Y E; Plazas, J; Marin, E

2017-12-01

In this work, oil samples extracted from organic and conventional coffee beans were studied. A fatty acids profile analysis was done using gas chromatography and physicochemical analysis of density and acidity index to verify the oil purity. Additionally, Mid-Infrared Fourier Transform Photoacoustic Spectroscopy (FTIR-PAS) aided by Principal Component Analysis (PCA) was used to identify differences between the intensities of the absorption bands related to functional groups. Thermal effusivity values between 592±3 and 610±4Ws 1/2 m -2 K -1 were measured using the photopyroelectric technique in a front detection configuration. The acidity index was between 1.11 and 1.27% and the density changed between 0.921 and 0.94g/mL. These variables, as well as the extraction yield between 12,6 and 14,4%, showed a similar behavior than that observed for the thermal effusivity, demonstrating that this parameter can be used as a criterion for discrimination between oil samples extracted from organic and conventional coffee beans. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cleanup procedure for water, soil, animal and plant extracts for the use of electron-capture detector in the gas chromatographic analysis of organophosphorus insecticide residues.

PubMed

Kadoum, A M

1968-07-01

A simple, aqueous acetonitrile partition cleanup method for analyses of some common organophosphorus insecticide residues is described. The procedure described is for cleanup and quantitative recovery of parathion, methyl parathion, diazinon, malathion and thimet from different extracts. Those insecticides in the purified extracts of ground water, grain, soil, plant and animal tissues can be detected quantitatively by gas chromatography with an electron capture-detector at 0.01 ppm. Cleanup is satisfactory for paper and thin-layer chromatography for further identification of individual insecticides in the extracts.

15 CFR Supplement No. 2 to Part 710 - Definitions of Production

Code of Federal Regulations, 2010 CFR

2010-01-01

... reaction Produced by synthesis* Formation through chemical synthesis.Processing to extract and isolate... (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS GENERAL INFORMATION AND OVERVIEW OF THE CHEMICAL WEAPONS CONVENTION REGULATIONS (CWCR) Pt. 710, Supp. 2...

[Determination of rhynchophylline and isorhynchophylline in Uncaria rhynchophylla by HPLC].

PubMed

Yang, Xiu-Juan; Hong, Yan-Long; Wu, Fei; Ruan, Ke-Feng; Feng, Yi

2013-03-01

To explore an HPLC method for determination of rhnchophylline and isorhnchophylline in Uncaria rhnchophylla. An HPLC method has been developed for determination of rhnchophylline and isorhnchophylline. The transformation of rhnchophylline and isorhnchophylline after heating was also studied by HPLC-ESI-MS. Good linearities of rhynchophylline and isorhynchophylline were 0.064-5.100, 0.064-5.110 mg, respectively. The average recoveries were from 87.51% to 88.83% for rhynchophylline and from 107.9% to 113.9% for isorhynchophylline. The recoveries of rhynchophylline and isorhnchophylline reference solutions after extraction were 12.60% and 40.00% in the reflux extraction procedure, respectively. While in the ultrasonic extraction procedure, the average recoveries of rhynchophylline and isorhynchophylline was from 99.48% to 103.2% and from 97.00% to 99.59%, resepectively. The recoveries of rhynchophylline and isorhnchophylline reference solutions after extraction were 47.08% and 51.03%, respectively. The unqualified recovery could be elucidated by HPLC-ESI-MS analysis, indicating that trhynchophylline could be transformed mostly into isorhynchophylline and a little amount of unkown composition, while isorhynchophylline could be transformed into rhynchophylline isocorynoxeine, corynoxeine and 22-O-beta-D-glucopyranosyl isocorynoxeinic acid during the extraction procedure. Ultrasonic extraction procedure was more sutble for HPLC determination of the content of rhynchophylline and isorhynchophylline in U. rhnchophylla, however, the recovery problems should be paid attention to when it comes to the determination.

Extraction and analysis of adenosine triphosphate from aquatic environments

USGS Publications Warehouse

Stephens, Doyle W.; Shultz, David J.

1981-01-01

A variety of adenosine triphosphate (ATP) extraction procedures have been investigated for their applicability to samples from aquatic environments. The cold sulfuric-oxalic acid procedure was best suited to samples consisting of water, periphyton, and sediments. Due to cation and fulvic acid interferences, a spike with a known quantity of ATP was necessary to estimate losses when sediments were extracted. Variable colonization densities for periphyton required that several replicates be extracted to characterize acdurately the periphyton community. Extracted samples were stable at room temperature for one to five hours, depending on the ATP concentration, if the pH was below 2. Neutralized samples which were quick frozen and stored at -30°C were stable for months.

Comparison of methods for hydrocarbon analysis of marine biota

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

Gritz, R.L.; Shaw, D.G.

1977-04-01

A comparison was made of several procedures for the isolation of hydrocarbons from other matter and for the fractionation of hydrocarbons according to chemical type. The efficiency of Soxhlet extraction followed by saponification with extraction by alkaline digestion (direct saponification) was compared using two hour and 24 hour reaction times. All procedures were performed on approximately 60 g of soft parts of Saxidomus gigantea (butter clam). The 24 hour saponification and column chromatography on partially deactivated columns constituted the best procedure tested. Soxhlet extraction followed by two hour saponification did not completely remove methyl esters and was the most laboriousmore » technique. Direct two hour saponification was also questionable in the removal of esters and led to severe emulsion problems. The recoveries of hydrocarbons by the three procedures was substantially the same.« less

Ionic-liquid-based ultrasound/microwave-assisted extraction of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and 6-methoxy-benzoxazolin-2-one from maize (Zea mays L.) seedlings.

PubMed

Li, Chunying; Lu, Zhicheng; Zhao, Chunjian; Yang, Lei; Fu, Yujie; Shi, Kunming; He, Xin; Li, Zhao; Zu, Yuangang

2015-01-01

We evaluated an ionic-liquid-based ultrasound/microwave-assisted extraction method for the extraction of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and 6-methoxy-benzoxazolin-2-one from etiolated maize seedlings. We performed single-factor and central composite rotatable design experiments to optimize the most important parameters influencing this technique. The best results were obtained using 1.00 M 1-octyl-3-methylimidazolium bromide as the extraction solvent, a 50°C extraction temperature, a 20:1 liquid/solid ratio (mL/g), a 21 min treatment time, 590 W microwave power, and 50 W fixed ultrasonic power. We performed a comparison between ionic-liquid-based ultrasound/microwave-assisted extraction and conventional homogenized extraction. Extraction yields of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and 6-methoxy-benzoxazolin-2-one by the ionic-liquid-based ultrasound/microwave-assisted extraction method were 1.392 ± 0.051 and 0.205 ± 0.008 mg/g, respectively, which were correspondingly 1.46- and 1.32-fold higher than those obtained by conventional homogenized extraction. All the results show that the ionic-liquid-based ultrasound/microwave-assisted extraction method is therefore an efficient and credible method for the extraction of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one and 6-methoxy-benzoxazolin-2-one from maize seedlings. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Radar, target and ranging

NASA Astrophysics Data System (ADS)

1984-09-01

This Test Operations Procedure (TOP) provides conventional test methods employing conventional test instrumentation for testing conventional radars. Single tests and subtests designed to test radar components, transmitters, receivers, antennas, etc., and system performance are conducted with single item instruments such as meters, generators, attenuators, counters, oscillators, plotters, etc., and with adequate land areas for conducting field tests.

Green synthesis of Copper nanoparticle using ionic liquid-based extraction from Polygonum minus and their applications.

PubMed

Ullah, Habib; Wilfred, Cecilia Devi; Shaharun, Maizatul Shima

2018-06-06

The present work reports the extraction of phenolic compounds from Polygonum minus using ionic liquid as extracting solvent. In this work, 1-Butyl-3-methylimidazolium hydrogen sulfate [BMIM][HSO 4 ] was used for the extraction of bioactive compounds. Accordingly, ionic liquids based microwave-assisted extraction treatment for separating of bioactive compounds from polygonum minus was first performed in the present study. The results obtained in this work have high extraction yield in comparison with conventional solvent. UV/Vis results showed that microwave synthesis was fast, well dispersed and nanosized copper nanoparticle (CuNPs) in comparison with conventional synthesis. CuNPs was characterized by X-Rays diffractometer (XRD), Fourier transform infrared (FTIR), dynamic light scattering (DLS), field emission scanning electron microscopy combined with energy dispersive x-rays (FESEM-EDX), and thermogravimetric analysis (TGA). All the instrumental analyses confirmed the particles were nanosized. Furthermore, the antibacterial activity of as-synthesized CuNPs showed effective inhibitory zone against three different bacteria. The photocatalytic degradation of copper nanoparticles was studied using methylene blue (MB) and methyl orange (MO) dyes under UV light and degraded 99.9% within short time 8 and 7 minutes.

Potential of capillary-column-switching liquid chromatography-tandem mass spectrometry for the quantitative trace analysis of small molecules. Application to the on-line screening of drugs in water.

PubMed

Pitarch, Elena; Hernandez, Felix; ten Hove, Jan; Meiring, Hugo; Niesing, Willem; Dijkman, Ellen; Stolker, Linda; Hogendoorn, Elbert

2004-03-26

We have investigated the potential of capillary-column-switching liquid chromatography coupled to tandem mass spectrometry (cLC-MS-MS) for the quantitative on-line trace analysis of target compounds in aqueous solutions. The technical design of the nano-scale cLC system developed at our Institute for peptide and protein identification has been tested and evaluated for the direct trace analysis of drugs in water samples. Sulphametoxazole, bezafibrate, metoprolol, carbamazepine and bisoprolol occurring frequently in Dutch waters, were selected as test compounds. Adequate conditions for trapping, elution and MS-MS detection were investigated by employing laboratory made 200 microm i.d. capillary columns packed with 5 microm aqua C18 material. In the final cLC-MS-MS conditions, a 1 cm length trapping column and a 4 cm length analytical column were selected. Under these conditions, the target compounds could be directly determined in water down to a level of around 50 ng/l employing only 25 microl of water sample. Validation was done by recovery experiments in ground-, surface- and drinking-water matrices as well as by the analysis of water samples with incurred residues and previously analyzed with a conventional procedure involving off-line solid-phase extraction and narrow-bore LC with MS-MS detection. The new methodology provided recoveries (50-500 ng/l level) between 50 and 114% with RSDs (n = 3, each level) below 20% for most of the compounds. Despite the somewhat less analytical performance in comparison to the conventional procedure, the on-line approach of the new methodology is very suitable for screening of drugs in aqueous samples.

Reservoir inflow forecasting with a modified coactive neuro-fuzzy inference system: a case study for a semi-arid region

NASA Astrophysics Data System (ADS)

Allawi, Mohammed Falah; Jaafar, Othman; Mohamad Hamzah, Firdaus; Mohd, Nuruol Syuhadaa; Deo, Ravinesh C.; El-Shafie, Ahmed

2017-10-01

Existing forecast models applied for reservoir inflow forecasting encounter several drawbacks, due to the difficulty of the underlying mathematical procedures being to cope with and to mimic the naturalization and stochasticity of the inflow data patterns. In this study, appropriate adjustments to the conventional coactive neuro-fuzzy inference system (CANFIS) method are proposed to improve the mathematical procedure, thus enabling a better detection of the high nonlinearity patterns found in the reservoir inflow training data. This modification includes the updating of the back propagation algorithm, leading to a consequent update of the membership rules and the induction of the centre-weighted set rather than the global weighted set used in feature extraction. The modification also aids in constructing an integrated model that is able to not only detect the nonlinearity in the training data but also the wide range of features within the training data records used to simulate the forecasting model. To demonstrate the model's efficacy, the proposed CANFIS method has been applied to forecast monthly inflow data at Aswan High Dam (AHD), located in southern Egypt. Comparative analyses of the forecasting skill of the modified CANFIS and the conventional ANFIS model are carried out with statistical score indicators to assess the reliability of the developed method. The statistical metrics support the better performance of the developed CANFIS model, which significantly outperforms the ANFIS model to attain a low relative error value (23%), mean absolute error (1.4 BCM month-1), root mean square error (1.14 BCM month-1), and a relative large coefficient of determination (0.94). The present study ascertains the better utility of the modified CANFIS model in respect to the traditional ANFIS model applied in reservoir inflow forecasting for a semi-arid region.

Utility of conventional transbronchial needle aspiration with rapid on-site evaluation (c-TBNA-ROSE) at a tertiary care center with endobronchial ultrasound (EBUS) facility

PubMed Central

Madan, Neha Kawatra; Madan, Karan; Jain, Deepali; Walia, Ritika; Mohan, Anant; Hadda, Vijay; Mathur, Sandeep; Iyer, Venkateswaran K; Khilnani, Gopi C; Guleria, Randeep

2016-01-01

Background: Conventional transbronchial needle aspiration (c-TBNA) is an underutilized bronchoscopic modality. Endobronchial ultrasound (EBUS) guided-TBNA though efficacious is an expensive modality, facilities of which are available at only limited centers. c-TBNA is cost-effective and has potential for wide utilization especially in resource-limited settings. Rapid on-site evaluation (ROSE) improves the yield of c-TBNA. Materials and Methods: A retrospective review of the bronchoscopy records (May 2012 to July 2014) was performed. The patients who underwent c-TBNA with ROSE were included in the study and their clinical details were extracted. Convex probe EBUS-TBNA was being regularly performed during the study period by the operators performing c-TBNA. Results: c-TBNA with ROSE was performed in 41 patients with mean age of 42.4 (16.2) years. The most frequently sampled node stations (>90% patients) were the subcarinal and lower right paratracheal. Representative samples could be obtained in 33 out of the 41 patients (80.4%). c-TBNA was diagnostic in 32 [tuberculosis (TB)-8, sarcoidosis-9, and malignancy-15] patients out of the 41 patients. The overall diagnostic yield (sensitivity) of c-TBNA with ROSE was 78%. Mean procedure duration was 18.4 (3.1) min and there were no procedural complications. Conclusion: c-TBNA with ROSE is a safe, efficacious, and cost-effective bronchoscopic modality. When it was performed by operators routinely performing EBUS-TBNA, diagnostic yields similar to that of EBUS-TBNA can be obtained. Even at the centers where EBUS facilities are available, c-TBNA should be routinely performed. PMID:27011437

Light-emitting nanolattices with enhanced brightness

NASA Astrophysics Data System (ADS)

Ng, Ryan C.; Mandal, Rajib; Anthony, Rebecca J.; Greer, Julia R.

2017-02-01

Three-dimensional (3D) photonic crystals have potential in solid state lighting applications due to their advantages over conventional planar thin film devices. Periodicity in a photonic crystal structure enables engineering of the density of states to improve spontaneous light emission according to Fermi's golden rule. Unlike planar thin films, which suffer significantly from total internal reflection, a 3D architectured structure is distributed in space with many non-flat interfaces, which facilitates a substantial enhancement in light extraction. We demonstrate the fabrication of 3D nano-architectures with octahedron geometry that utilize luminescing silicon nanocrystals as active media with an aluminum cathode and indium tin oxide anode towards the realization of a 3D light emitting device. The developed fabrication procedure allows charge to pass through the nanolattice between two contacts for electroluminescence. These initial fabrication efforts suggest that 3D nano-architected devices are realizable and can reach greater efficiencies than planar devices.

Lasers in oral surgery and implantology

NASA Astrophysics Data System (ADS)

Vescovi, Paolo

2016-03-01

The usefulness of laser for oral hard tissue procedure such as caries treatment, impacted teeth extraction, periodontal therapy, peri-implantitis management, sinus lifting is reported by several Authors [1]. Conventionally, mechanical rotary instruments and hand instruments are employed for bone surgery. Rotary instruments have better accessibility and cutting efficiency, but there is a risk of excessive heating of bone tissue and caution must be exercised to avoid the bur becoming entangled with surrounding soft tissues and the reflected flap. The main clinical advantages of the lasers are represented by minimal patient discomfort, good recovery with decreased or absent post-operative pain. In the last ten years are described in the international literature great advantages of Laser Surgery and Low Level Laser Therapy (LLLT) performed with different wavelength in addition to traditional surgical techniques to improve bone and soft tissue healing and for pain and infection control.

Use of a Piezosurgery Technique to Remove a Deeply Impacted Supernumerary Tooth in the Anterior Maxilla

PubMed Central

Sukegawa, Shintaro; Kanno, Takahiro; Kawakami, Kiyokazu; Shibata, Akane; Takahashi, Yuka; Furuki, Yoshihiko

2015-01-01

Deeply impacted supernumerary teeth in the anterior maxillary cannot be generally removed by the conventional labial or palatal surgical approach because of the risk of damaging the surrounding soft tissues and the possibility of injuring the roots of adjacent permanent teeth. In piezosurgery, bony tissues are selectively cut, thereby avoiding the soft tissue damage caused by rotary cutting instruments. We report the case of a 15-year-old Japanese boy from whom a deeply impacted supernumerary tooth in the anterior maxillary was safely removed through the floor of the nasal cavity. The surgical extraction was performed without damaging the nasal mucosa or adjacent structures such as the roots of the adjacent permanent teeth. Considering that piezosurgery limits the extent of surgical invasion, this technique can be practiced as a minimally invasive and safe surgical procedure for treating suitably selected cases with a deeply impacted supernumerary tooth. PMID:26779355

Piezosurgery versus conventional surgery in radicular cyst enucleation.

PubMed

Kocyigit, Ismail Doruk; Atil, Fethi; Alp, Yunus Emre; Tekin, Umut; Tuz, Hakan H

2012-11-01

This study compared the use of piezosurgery and conventional surgery in radicular cyst enucleation. The study was conducted with 29 patients who were radiologically and cytologically prediagnosed with radicular cysts in the jaw region. Nineteen patients were treated using piezosurgery, and 10 were treated using conventional surgical procedures. Surgical procedures were evaluated according to the following criteria: hemorrhage, soft-tissue damage, manipulation complexity, major perforation areas on the enucleated cyst tissue, and approximate operation duration. Patients were monitored postoperatively and evaluated for hemorrhaging at 24, 48, and 72 hours following surgery. Follow-up was conducted to check for recurrences and ranged from 5 to 24 months. No complications were observed in any of the 20 patients treated using piezosurgery, although the duration of surgery was longer than expected. Of the 10 patients treated using conventional methods, hemorrhaging that affected the operation occurred in 3 cases, perforation of the cyst epithelium and difficulties in enucleation occurred in 5 cases, postoperative hemorrhage occurred in 2 cases, and recurrence was observed in 2 cases. Piezosurgery may be considered effective in procedures such as enucleation that require sensitive manipulation, despite the increase in the length of the overall surgical procedure. Given the results of the present study and the current lack of information in the literature regarding postoperative pain, infection, and long-term success rates associated with the use of piezosurgery in cyst enucleation, further study in this area is recommended.

Patient-specific geometrical modeling of orthopedic structures with high efficiency and accuracy for finite element modeling and 3D printing.

PubMed

Huang, Huajun; Xiang, Chunling; Zeng, Canjun; Ouyang, Hanbin; Wong, Kelvin Kian Loong; Huang, Wenhua

2015-12-01

We improved the geometrical modeling procedure for fast and accurate reconstruction of orthopedic structures. This procedure consists of medical image segmentation, three-dimensional geometrical reconstruction, and assignment of material properties. The patient-specific orthopedic structures reconstructed by this improved procedure can be used in the virtual surgical planning, 3D printing of real orthopedic structures and finite element analysis. A conventional modeling consists of: image segmentation, geometrical reconstruction, mesh generation, and assignment of material properties. The present study modified the conventional method to enhance software operating procedures. Patient's CT images of different bones were acquired and subsequently reconstructed to give models. The reconstruction procedures were three-dimensional image segmentation, modification of the edge length and quantity of meshes, and the assignment of material properties according to the intensity of gravy value. We compared the performance of our procedures to the conventional procedures modeling in terms of software operating time, success rate and mesh quality. Our proposed framework has the following improvements in the geometrical modeling: (1) processing time: (femur: 87.16 ± 5.90 %; pelvis: 80.16 ± 7.67 %; thoracic vertebra: 17.81 ± 4.36 %; P < 0.05); (2) least volume reduction (femur: 0.26 ± 0.06 %; pelvis: 0.70 ± 0.47, thoracic vertebra: 3.70 ± 1.75 %; P < 0.01) and (3) mesh quality in terms of aspect ratio (femur: 8.00 ± 7.38 %; pelvis: 17.70 ± 9.82 %; thoracic vertebra: 13.93 ± 9.79 %; P < 0.05) and maximum angle (femur: 4.90 ± 5.28 %; pelvis: 17.20 ± 19.29 %; thoracic vertebra: 3.86 ± 3.82 %; P < 0.05). Our proposed patient-specific geometrical modeling requires less operating time and workload, but the orthopedic structures were generated at a higher rate of success as compared with the conventional method. It is expected to benefit the surgical planning of orthopedic structures with less operating time and high accuracy of modeling.

Emerging Trends in Microwave Processing of Spices and Herbs.

PubMed

Rahath Kubra, Ismail; Kumar, Devender; Jagan Mohan Rao, Lingamallu

2016-10-02

Today, spices are integral part of our food as they provide sensory attributes such as aroma, color, flavour and taste to food. Further their antimicrobial, antioxidant, pharmaceutical and nutritional properties are also well known. Since spices are seasonal so their availability can be extended year round by adopting different preservation techniques. Drying and extraction are most important methods for preservation and value addition to spices. There are different techniques for drying of spices with their own advantages and limitations. A novel, non-conventional technique for drying of spices is use of microwave radiation. This technique proved to be very rapid, and also provide a good quality product. Similarly, there are a number of non-conventional extraction methods in use that are all, in principle, solid-liquid extractions but which introduce some form of additional energy to the process in order to facilitate the transfer of analytes from sample to solvent. This paper reviews latest advances in the use of microwave energy for drying of spices and herbs. Also, the review describes the potential application of microwave energy for extraction of essential oil/bioactive components from spices and herbs and the advantages of microwave-assisted process over the other extraction processes generally employed for extraction. It also showcases some recent research results on microwave drying/extraction from spices and herbs.

Influence of conventional and ultrasonic-assisted extraction on phenolic contents, betacyanin contents, and antioxidant capacity of red dragon fruit (Hylocereus polyrhizus).

PubMed

Ramli, Nurul Shazini; Ismail, Patimah; Rahmat, Asmah

2014-01-01

The aim of this study was to examine the effects of extraction methods on antioxidant capacities of red dragon fruit peel and flesh. Antioxidant capacities were measured using ethylenebenzothiozoline-6-sulfonic acid (ABTS) radical cation assay and ferric reducing antioxidant power assay (FRAP). Total phenolic content (TPC) was determined using Folin-Ciocalteu reagent while quantitative determination of total flavonoid content (TFC) was conducted using aluminium trichloride colorimetric method. Betacyanin content (BC) was measured by spectrophotometer. Red dragon fruit was extracted using conventional (CV) and ultrasonic-assisted extraction (UE) technique to determine the most efficient way of extracting its antioxidant components. Results indicated that UE increased TFC, reduced the extraction yield, BC, and TPC, but exhibited the strongest scavenging activity for the peel of red dragon fruit. In contrast, UE reduced BC, TFC, and scavenging activity but increased the yield for the flesh. Nonetheless, UE slightly increases TPC in flesh. Scavenging activity and reducing power were highly correlated with phenolic and flavonoid compounds. Conversely, the scavenging activity and reducing power were weakly correlated with betacyanin content. This work gives scientific evidences for the consideration of the type of extraction techniques for the peel and flesh of red dragon fruit in applied research and food industry.

Extraction and purification of high added value compounds from by-products of the winemaking chain using alternative/nonconventional processes/technologies.

PubMed

Yammine, Sami; Brianceau, Sylène; Manteau, Sébastien; Turk, Mohammad; Ghidossi, Rémy; Vorobiev, Eugène; Mietton-Peuchot, Martine

2018-05-24

Grape byproducts are today considered as a cheap source of valuable compounds since existent technologies allow the recovery of target compounds and their recycling. The goal of the current article is to explore the different recovery stages used by both conventional and alternative techniques and processes. Alternative pre-treatments techniques reviewed are: ultrasounds, pulsed electric fields and high voltage discharges. In addition, nonconventional solvent extraction under high pressure, specifically, supercritical fluid extraction and subcritical water extraction are discussed. Finally alternative purification technologies, for example membrane processing were also examined. The intent is to describe the mechanisms involved by these alternative technologies and to summarize the work done on the improvement of the extraction process of phenolic compounds from winery by-products. With a focus on the developmental stage of each technology, highlighting the research need and challenges to be overcome for an industrial implementation of these unitary operations in the overall extraction process. A critical comparison of conventional and alternative techniques will be reviewed for ethe pre-treatment of raw material, the diffusion of polyphenols and the purification of these high added value compounds. This review intends to give the reader some key answers (costs, advantages, drawbacks) to help in the choice of alternative technologies for extraction purposes.

Ultrasound-Assisted Extraction May Not Be a Better Alternative Approach than Conventional Boiling for Extracting Polysaccharides from Herbal Medicines.

PubMed

Yip, Ka-Man; Xu, Jun; Tong, Wing-Sum; Zhou, Shan-Shan; Yi, Tao; Zhao, Zhong-Zhen; Chen, Hu-Biao

2016-11-18

In clinical practice polysaccharides from herbal medicines are conventionally prepared by boiling water extraction (BWE), while ultrasound-assisted extraction (UAE) has often been used instead employed in laboratory research due to its strong extraction ability and efficiency. However, if and how the polysaccharides obtained by UAE and BWE are comparable, and hence whether the UAE-based research is instructive for the actual usage of herbal polysaccharides still requires further evaluation. To address this issue, here we chemically analyzed and compared the UAE- and BWE-obtained polysaccharides from three herbal medicines, i.e., Ginseng Radix, Astragali Radix and Dendrobii Officinalis Caulis. Then, the spike recovery of two series of standard dextran and pullulan by UAE and BWE was tested. The results showed that the polysaccharides from the herbal medicines by UAE were quantitatively and qualitatively different with those by BWE. The powerful extraction ability and polysaccharide degradation caused by ultrasound collectively contributed to these differences. It was then revealed that not only the UAE conditions but also the polysaccharide structures could affect the extraction ability and polysaccharide degradation. Given these, we highly recommended that the effects of UAE on polysaccharides from herbal medicines should be first carefully considered before employing it in relevant chemical and pharmacological analysis.