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Search Results: 1 - 10 of 5647 matches for " extraction "
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Chunk Parsing and Entity Relation Extracting to Chinese Text by Using Conditional Random Fields Model  [PDF]
Junhua Wu, Longxia Liu
Journal of Intelligent Learning Systems and Applications (JILSA) , 2010, DOI: 10.4236/jilsa.2010.23017
Abstract: Currently, large amounts of information exist in Web sites and various digital media. Most of them are in natural lan-guage. They are easy to be browsed, but difficult to be understood by computer. Chunk parsing and entity relation extracting is important work to understanding information semantic in natural language processing. Chunk analysis is a shallow parsing method, and entity relation extraction is used in establishing relationship between entities. Because full syntax parsing is complexity in Chinese text understanding, many researchers is more interesting in chunk analysis and relation extraction. Conditional random fields (CRFs) model is the valid probabilistic model to segment and label sequence data. This paper models chunk and entity relation problems in Chinese text. By transforming them into label solution we can use CRFs to realize the chunk analysis and entities relation extraction.
Comparison between Forceps, Single Blade Forceps and Manual Extraction of Fetal Head in Elective Caesarean Section: A Randomized Control Trial—Forceps Delivery in Cesarean Section  [PDF]
Ahmed Sherif Abdel Hamid Abdel Wahab, Ashraf Sobhy Aboulouz
Open Journal of Obstetrics and Gynecology (OJOG) , 2018, DOI: 10.4236/ojog.2018.81004
Abstract: Objective: The fundal pressure exerted by the assistant to deliver fetal head is often painful to the patient. This study assesses the use of double blade forceps in delivery of fetal head at time of elective Cesarean Section (CS). Methods: A prospective single-blinded randomized controlled trial was conducted among 150 women with repeat elective CS at Ain Shams university hospital, Air Force Specialized hospital and October 6th university hospital. Women were classified into 3 groups (each 50 women). Forceps group: A double blade of forceps was used without fundal pressure. Single blade group: single blade of forceps was used assisted by fundal pressure. Manual group: manual extraction was used assisted by fundal pressure. The outcome of study were; Pain expectation score , pain score during delivery of head, unintended uterine extension, uterine vessels injury and need for additional stitches. The collected data were statistically analyzed using SPSS version 20. Results: High Statistically significant difference in pain score during delivery of head in favor of forceps group (P = 0.001). No differences were found among 3 groups as regarding pain expectation, uterine extension, uterine vessel injury and in need of haemostatic stitches (P > 0.05).
A Simple Approach for Evaluating Total MicroRNA Extraction from Mouse Brain Tissues  [PDF]
Jack G. Walleshauser III, Trace Kessler, Danielle Morse, Bakhos A. Tannous, Norman H. L. Chiu
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2012, DOI: 10.4236/jasmi.2012.21002
Abstract: For the analysis of microRNA, a common approach is to first extract microRNA from cellular samples prior to any specific microRNA detection. Thus, it is important to determine the quality and yield of extracted microRNA. In this study, solid-phase extraction was used to isolate small RNA (<200 nt), which included microRNA, from mouse brain tissues. By using standard UV absorbance measurements, the amount of small RNA in the extracted RNA samples was determined. To determine the presence of microRNA, each RNA sample was analyzed by PAGE with SYBR? Green II staining. Testing for contamination of any small DNA fragments, RNase and cellular peptides or proteins were systematically carried out. By scanning the gel image obtained from PAGE analysis, the average percentage of total microRNA (19 - 25 nt) in the extracted RNA samples was determined to be equal to 2.3 ± 0.5%. The yield of total microRNA was calculated to be ~0.5ng of microRNA per milligram of frozen mouse brain tissue. In comparison to other methods that require the use of expensive specialized instrumentation, the approach of combining the standard UV absorbance and PAGE analysis represents a simple and viable method for evaluating the quality and yield of microRNA extraction from tissue samples.
Studies on Extraction Behaviour of Cobalt(II) with Nitrobenzoylprazolone-5  [PDF]
Onyedika Gerald, Arinze Judith, Ogwuegbu Martin
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2013, DOI: 10.4236/jmmce.2013.13017
Abstract: The extraction of Cobalt(II) from aqueous solution using 1-phenyl-3-methyl-4-(p-nitrobenzoyl)pyrazolone (HPMNP) in various organic solvents was studied as a function of pH and extractant concentration. Extraction into organic chloroform phase was more efficient than with any other solvent. The extraction equilibrium constant was found to be log Kex= -7.04. Optimum conditions for extraction of Co(II) exist at pH of between 5.5 and 7.0, ionic strength of 0.3 Mand constant extractant concentration of 0.02 M. Shaking the organic Co(II) chelate complex with 0.2 Macid strips the Co(II) ions into the aqueous phase. It was established that Co(II) complex extracted is of composition, Co(PMNP)2.
Extraction and Modelling of Oil from Eucalyptus camadulensis by Organic Solvent  [PDF]
Khalid M. Abed, Badoor M. Kurji, Basma A. Abdul-Majeed
Journal of Materials Science and Chemical Engineering (MSCE) , 2015, DOI: 10.4236/msce.2015.38006
Abstract: This work was conducted to study the extraction of eucalyptus oil from natural plants (Eucalyptus camadulensis leaves) by organic solvents. the effects of the main operating parameters were studied; type of solvent (n-hexane and ethanol), time to reach equilibrium, the temperature (45°C to 65°C) for n-hexane and (45°C to 75°C) for ethanol, solvent to solid ratio (5:1 to 8:1 (v/w)), agitation speed (0 to 900 rpm) and the particle size (0.5 to 2.5 cm) of fresh leaves to find the best processing conditions for the achieving maximum oil yield. The concentration of eucalyptus oil in solvent was measured by using UV-spectrophotometer. The results (for n-hexane) showed that the agitation speed of 900 rpm, temperature 65°C with solvent to solid ratio 7:1 (v/w) of particle size 0.5 cm for 210 minute give the highest value of oil (68.5 wt%). Similar conditions for ethanol with the exception of the temperature (75°C) give the highest yield of oil (65.07 wt%).
DNA Extraction from Insects by Using Different Techniques: A Review  [PDF]
Usman Asghar, Muhammad Faheem Malik, Fakhra Anwar, Ayesha Javed, Ali Raza
Advances in Entomology (AE) , 2015, DOI: 10.4236/ae.2015.34016
Abstract: This review paper was prepared at Department of Zoology, University of Gujrat, Pakistan during 2014-2015. The data for the two decades, DNA Extraction from Insects by Using Different Techniques was compiled through a thorough review of many research articles published in various journals of international repute. Insects are very important economically and ecologically for human due to their various roles, as pests, decomposer in nutrition cycle, vector for the transmission of certain diseases and a source of medically and economically important products. To identify insect, and for research on their role, different molecular techniques are used. For each molecular technique, high quality DNA is required, which is extracted from the insects by different techniques. The selection of DNA extraction technique is depended upon specimen under study, time required for extraction, economical stander of technique due to reagents and equipment used for extraction and most importantly extracted DNA quality. In this paper, most frequently used techniques for DNA extraction from insect with different size and condition are outlined. This paper is only a guide for these techniques and we describe them briefly.
Real-Time Static Hand Gesture Recognition for American Sign Language (ASL) in Complex Background  [PDF]
Jayashree R. Pansare, Shravan H. Gawande, Maya Ingle
Journal of Signal and Information Processing (JSIP) , 2012, DOI: 10.4236/jsip.2012.33047
Abstract: Hand gestures are powerful means of communication among humans and sign language is the most natural and expressive way of communication for dump and deaf people. In this work, real-time hand gesture system is proposed. Experimental setup of the system uses fixed position low-cost web camera with 10 mega pixel resolution mounted on the top of monitor of computer which captures snapshot using Red Green Blue [RGB] color space from fixed distance. This work is divided into four stages such as image preprocessing, region extraction, feature extraction, feature matching. First stage converts captured RGB image into binary image using gray threshold method with noise removed using median filter [medfilt2] and Guassian filter, followed by morphological operations. Second stage extracts hand region using blob and crop is applied for getting region of interest and then “Sobel” edge detection is applied on extracted region. Third stage produces feature vector as centroid and area of edge, which will be compared with feature vectors of a training dataset of gestures using Euclidian distance in the fourth stage. Least Euclidian distance gives recognition of perfect matching gesture for display of ASL alphabet, meaningful words using file handling. This paper includes experiments for 26 static hand gestures related to A-Z alphabets. Training dataset consists of 100 samples of each ASL symbol in different lightning conditions, different sizes and shapes of hand. This gesture recognition system can reliably recognize single-hand gestures in real time and can achieve a 90.19% recognition rate in complex background with a “minimum-possible constraints” approach.
Pressurized Hot Water Extraction of Alkaloids in Goldenseal  [PDF]
Janes Mokgadi, Nelson Torto, Charlotta Turner
American Journal of Analytical Chemistry (AJAC) , 2013, DOI: 10.4236/ajac.2013.48050

A quick, efficient and environmentally beneficial approach for the extraction of alkaloids in goldenseal based on pressurized hot water extraction (PHWE) is presented. PHWE was evaluated following the extraction of hydrastine and berberine which are the two main alkaloids of goldenseal. The effects of temperature and other parameters on extraction yields were monitored by high performance liquid chromatography coupled to diode array detector (HPLC-DAD). The extraction yields were compared to those achieved through reflux and ultrasonic extraction methods. PHWE employed hot water at an optimal temperature of 140℃, a pressure of 50 bars and flow rate of 1 mL.min-1 for extraction experiments conducted in the dynamic mode. Both PHWE and conventional methods achieved comparable extraction yields. Reflux and ultrasonic extractions had procedures that were slower (over 6 h) and employed large quantities (200 mL) of organic solvents. The PHWE method was simple and relatively fast as extraction was achieved in 15 min. At 95% confidence level (n = 3), reflux and ultrasonic methods recorded extraction yields that were not

Applicability of Static Supercritical Carbon Dioxide Extraction in Biogeochemical Characterization of Oil Shales  [PDF]
Hans Luik, Lea Luik, Vilja Palu, Galina Sharayeva, Andre Gregor
American Journal of Analytical Chemistry (AJAC) , 2014, DOI: 10.4236/ajac.2014.53021
Abstract: This study aimed at the assessment of applicability of static supercritical carbon dioxide extraction method (SFE) in biogeochemical characterization of oil shales as an alternative to the standard Soxhlet extration. A comparative investigation on yields and compositions of the solvent soluble bitumoids and their constituents extracted from Estonian Kukersite and Dictyonema oil shales by using Soxhlet extraction method (SEM) and static CO2 supercritical fluid extraction in an autoclave at varied subpyrolysis temperatures was carried out. Resulting from TLC- and GC-MS-analyses, aliphatic and aromatic hydrocarbons and neutral oxygen compounds were separated and identified. For the first time, in the composition of the Kukersite bitumoid, homologous series of n-alkanones-3 to n-alkanones-7 were detected. The extracts obtained were similar in both group and individual composition, and geochemical parametres calculated on the basis of aliphatic hydrocarbons including that made static SFE applicable to geochemical investigation of oil shales.
Optimization of Sesame Oil Extraction Process Conditions  [PDF]
Abubakr Elkhaleefa, Ihab Shigidi
Advances in Chemical Engineering and Science (ACES) , 2015, DOI: 10.4236/aces.2015.53031
Abstract: In this study, the optimum operating conditions for sesame oil extraction were studied. N-hexane was used as a solvent. Different variables were investigated; sesame seeds particle sizes, ratio of solvent to seeds mass, contact time, stirring effect, roasting impact and extraction temperatures. Results obtained showed that higher rates of extraction were obtained when roasting sesame seed to 15. The ratio of solvent to seeds found to be 6:1 gave higher extraction. Moreover, stirring speed was tested and had been optimized to 600 rpm. Finally, the extraction under heating was studied and results showed that increasing operating temperature to more than 40 did not increase extraction efficiency.
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