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Terrorism Attack Classification Using Machine Learning: The Effectiveness of Using Textual Features Extracted from GTD Dataset
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作者 Mohammed Abdalsalam Chunlin Li +1 位作者 Abdelghani Dahou Natalia Kryvinska 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1427-1467,共41页
One of the biggest dangers to society today is terrorism, where attacks have become one of the most significantrisks to international peace and national security. Big data, information analysis, and artificial intelli... One of the biggest dangers to society today is terrorism, where attacks have become one of the most significantrisks to international peace and national security. Big data, information analysis, and artificial intelligence (AI) havebecome the basis for making strategic decisions in many sensitive areas, such as fraud detection, risk management,medical diagnosis, and counter-terrorism. However, there is still a need to assess how terrorist attacks are related,initiated, and detected. For this purpose, we propose a novel framework for classifying and predicting terroristattacks. The proposed framework posits that neglected text attributes included in the Global Terrorism Database(GTD) can influence the accuracy of the model’s classification of terrorist attacks, where each part of the datacan provide vital information to enrich the ability of classifier learning. Each data point in a multiclass taxonomyhas one or more tags attached to it, referred as “related tags.” We applied machine learning classifiers to classifyterrorist attack incidents obtained from the GTD. A transformer-based technique called DistilBERT extracts andlearns contextual features from text attributes to acquiremore information from text data. The extracted contextualfeatures are combined with the “key features” of the dataset and used to perform the final classification. Thestudy explored different experimental setups with various classifiers to evaluate the model’s performance. Theexperimental results show that the proposed framework outperforms the latest techniques for classifying terroristattacks with an accuracy of 98.7% using a combined feature set and extreme gradient boosting classifier. 展开更多
关键词 Artificial intelligence machine learning natural language processing data analytic DistilBERT feature extraction terrorism classification GTD dataset
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Applications of SMILE-extracted lenticules in ophthalmology
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作者 Hossein Aghamollaei Hassan Hashemi +3 位作者 Mahsa Fallahtafti Seyed-Hashem Daryabari Mehdi Khabazkhoob Khosrow Jadidi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期173-187,共15页
AIM:To review recent innovations,challenges,and applications of small incision lenticule extraction(SMILE)extracted lenticule for treating ocular disorders.METHODS:A literature review was performed in the PubMed datab... AIM:To review recent innovations,challenges,and applications of small incision lenticule extraction(SMILE)extracted lenticule for treating ocular disorders.METHODS:A literature review was performed in the PubMed database,which was last updated on 30 December 2021.There was no limit regarding language.The authors evaluated the reference lists of the collected papers to find any relevant research.RESULTS:Due to the simplicity and accuracy of modern femtosecond lasers and the extensive development of SMILE surgery,many healthy human corneal stromal lenticules were extracted during surgery,motivating some professionals to investigate the SMILE lenticule reusability in different ocular disorders.In addition,new approaches had been developed to preserve,modify,and bioengineer the corneal stroma,leading to the optimal use of discarded byproducts such as lenticules from SMILE surgery.The lenticules can be effectively re-implanted into the autologous or allogenic corneas of human subjects to treat refractive errors,corneal ectasia,and corneal perforation and serve as a patch graft for glaucoma drainage devices with better cosmetic outcomes.CONCLUSION:SMILE-extracted lenticules could be a viable alternative to human donor corneal tissue. 展开更多
关键词 small incision lenticule extraction corneal lenticule implantation KERATOCONUS corneal perforation femtosecond laser stromal keratophakia
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Extraction, Production and Quality Evaluation of Margarine from Oil Extracted from Waste Biomass Peels of Avocado and Virgin Coconut Oil, Using Chitosan from Reared Shells as Preservative
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作者 Suh-Ndale Svetlana Miyanui Pride Ndasi Ngwasiri +3 位作者 Wiyeh Claudette Bakisu Muala Noumo Thierry Ngangmou Wilson Agwanande Ambindei Martin Benoit Ngassoum 《Journal of Agricultural Chemistry and Environment》 2024年第1期142-168,共27页
The production and consumption of avocado pears generates tons of wastes, mainly the pear peels which are usually discarded, although they have been reported to contain important phyto-chemicals with biological activi... The production and consumption of avocado pears generates tons of wastes, mainly the pear peels which are usually discarded, although they have been reported to contain important phyto-chemicals with biological activities. The adverse health effect associated with the consumption of saturated lipid based foods has ignited research on reformulation of lipid based foods to eliminate Trans Fatty Acids (TFAs). This study was thus aimed at the extraction and characterization of oil from Avocado Peels (APO) and evaluation of the quality of margarine produced from it. Five verities of pear were used for oil extraction by soxhlet method and physiochemical, oxidative, functional and antioxidant characterization was done. Margarines were formulated using a central composite design using oil blends of APO and Virgin Coconut Oil (VCO) with an oil ratio of 10:90, 40:60, 70:30 respectively, varied blending speed, blending time, and chitosan concentration. Samples were characterized and the effect of process parameters on the physiochemical and functional properties of the margarine studied. Optimized conditions were used to produce samples for sensory evaluation. Color, spreadability, aroma, taste and general acceptability was evaluated using ranking difference test. The results showed that the yield, density, and iodine values of APOs oils ranged from 14.91 ± 0.18 to 11.76 ± 0.46;0.93 ± 0.001 to 0.99 ± 0.1;46.63 ± 1.70 to 52.4 ± 0.63, their acid values, TBA and PV values ranged from 1.42 ± 0.39 to 1.97 ± 0.5;0.11 ± 0.002 to 0.18 ± 0.04;and 2.72 ± 0.14 to 4.43 ± 0.36 respectively, with Brogdon avocado peel variety having the overall best properties prepared blends of trans-free APO margarines showed that increase in APO ratio decreased melting point, increased oxidative stability and reduced moisture content of margarine samples. Chitosan addition leads to decrease moisture content and increase functional properties. VCO lead to increase in phenolic and flavonoid content of the margarines. Samples were spreadable and palatable with R20 being most palatable and the most accepted being R26 with a mean score of 7.07 ± 0.70. Decrease in color intensity increased acceptability. This study therefore demonstrated that avocado peel waste biomass can be valorized by using it as raw material for oil extraction, which can serve as good material for the production of trans-free margarines with good oxidative stability, functional and antioxidant properties. 展开更多
关键词 Food Waste Avocado Peels EXTRACTION OIL Biological Activity MARGARINE CHITOSAN
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Physicochemical properties and biological activities of polysaccharides from the peel of Dioscorea opposita Thunb.extracted by four different methods 被引量:2
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作者 Zuowei Zhao Li Wang +4 位作者 Yuan Ruan Chunnan Wen Menghuan Ge Yanyan Qian Bingji Ma 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期130-139,共10页
Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-com... Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP. 展开更多
关键词 Dioscorea opposita Thunb peel POLYSACCHARIDES Different extraction methods Physicochemical characteristics Biological activities
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Biosynthesis and Characterization of Silver Nanoparticles Coated with Metabolites Extracted from Clerodendron phlomoides with Its Biochemical Studies in Liver Tissue
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作者 Subha Veeramani Kirubanandan Shanmugam 《Proceedings of Anticancer Research》 2023年第4期1-19,共19页
Silver nanoparticles(AgNPs)have been used as a potential nanomaterial-based drug delivery vehicle for liver cancer treatment,as it induces cell death and produces cytotoxicity against cancerous cells at a low concentr... Silver nanoparticles(AgNPs)have been used as a potential nanomaterial-based drug delivery vehicle for liver cancer treatment,as it induces cell death and produces cytotoxicity against cancerous cells at a low concentration.The biosynthesis of green metallic nanoparticles uses secondary metabolites in plant extracts instead of toxic chemicals for a reduction-oxidation(redox)reaction.The biosynthesis of AgNPs with the aqueous extract of Clerodendron phlomoides was performed in this study.The phytochemical analysis of C.phlomoides extract using gas chromatography-mass spectrometry(GC-MS)confirmed the presence of redox metabolites.The peak at 489 nm in UV-visible spectra confirmed the formation of bioactive AgNPs reduced from silver nitrate solution,whereas the Fourier-transform infrared(FTIR)spectra indicated the bioactive molecules of plant extracts that are responsible for the formation.Scanning electron microscope(SEM)micrograph revealed the formation of spherical and ovoid structures of AgNPs,whereas transmission electron microscope(TEM)micrograph confirmed the size of AgNPs,which varies from 25 nm to 100 nm.X-ray diffraction(XRD)spectra showed the crystalline nature of AgNPs,and the size of crystallite was 4 nm,while dynamic light scattering(DLS)analysis confirmed the average particle size of AgNPs to be around 125 nm.In vivo studies showed that bioactive AgNPs have a significant anticancer potential against liver cancer,whereas biochemical studies of rats’liver tissue samples confirmed that bioactive AgNPs produced a potential hepatoprotective effect against diethylnitrosamine-induced liver cancer. 展开更多
关键词 Silver nanoparticles Clerodendron phlomoides Aqueous extract SEM TEM Liver cancer
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Polyphenols extracted from Aronia melanocarpa by combined enzymatic and ultrasonication and their antioxidant potential and antimicrobial activity
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作者 Xinzhu Zhang Ming Song +1 位作者 Weizhuo Xu Wei Xu 《Journal of Polyphenols》 2023年第1期35-47,共13页
The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction condit... The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction conditions were 1%enzyme,1:40 material-to-liquid ratio,55℃,60 min ultrasonication,70%ethanol,and the final extraction amount was 88.634 mg/g,which displayed a 25.15%and 34.08%improvement compared with the single ultrasonication and enzymatic extraction methods,respectively.Significant antibacterial effects of polyphenols were shown against Staphylococcus aureus,Escherichia coli and Bacillus subtilis.Further antioxidation effects were evaluated,and the superoxide anion radical scavenging rate,hydroxyl radical scavenging rate and DPPH free radical scavenging rate reached 45.2%,83.5%and 85.4%,respectively.This combined enzymatic and ultrasonic extraction method exhibited the advantages of high extraction rate,saving solvent consumption and extraction time,but also provided a new method for the development and utilization of natural antimicrobial and antioxidant health products. 展开更多
关键词 Aronia melanocarpa phenolic compounds enzymatic extraction ultrasonication antibacterial effect antioxidation effect
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Chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor promotes sciatic nerve repair 被引量:7
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作者 Yanru Zhang Hui Zhang +1 位作者 Kaka Katiella Wenhua Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第14期1358-1364,共7页
A chemically extracted acellular allogeneic nerve graft can reduce postoperative immune rejection, similar to an autologous nerve graft, and can guide neural regeneration. However, it remains poorly understood whether... A chemically extracted acellular allogeneic nerve graft can reduce postoperative immune rejection, similar to an autologous nerve graft, and can guide neural regeneration. However, it remains poorly understood whether a chemically extracted acellular allogeneic nerve graft combined with neurotrophic factors provides a good local environment for neural regeneration. This study investigated the repair of injured rat sciatic nerve using a chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor. An autologous nerve anastomosis group and a chemical acellular allogeneic nerve bridging group were prepared as controls. At 8 weeks after repair, sciatic functional index, evoked potential amplitude of the soleus muscle, triceps wet weight recovery rate, total number of myelinated nerve fibers and myelin sheath thickness were measured. For these indices, values in the three groups showed the autologous nerve anastomosis group 〉 chemically extracted acellular nerve graft + ciliary neurotrophic factor group 〉 chemical acellular allogeneic nerve bridging group. These results suggest that chemically extracted acellular nerve grafts combined with ciliary neurotrophic factor can repair sciatic nerve defects, and that this repair is inferior to autologous nerve anastomosis, but superior to chemically extracted acellular allogeneic nerve bridging alone. 展开更多
关键词 nerve regeneration peripheral nerve injury chemically extracted acellular allogeneic nerve DEFECT repair TRANSPLANTATION ciliary neurotrophic factor autologous nerve neural regeneration
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Repair of peripheral nerve defects with chemically extracted acellular nerve allografts loaded with neurotrophic factors-transfected bone marrow mesenchymal stem cells 被引量:6
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作者 Yan-ru Zhang Ka Ka +4 位作者 Ge-chen Zhang Hui Zhang Yan Shang Guo-qiang Zhao Wen-hua Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第9期1498-1506,共9页
Chemically extracted acellular nerve allografts loaded with brain-derived neurotrophic fac- tor-transfected or ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells have been shown to repair sciat... Chemically extracted acellular nerve allografts loaded with brain-derived neurotrophic fac- tor-transfected or ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells have been shown to repair sciatic nerve injury better than chemically extracted acellular nerve allografts alone, or chemically extracted acellular nerve allografts loaded with bone marrow mesenchymal stem cells. We hypothesized that these allografts compounded with both brain-derived neurotrophic factor- and ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells may demonstrate even better effects in the repair of peripheral nerve injury. We cultured bone marrow mesenchymal stem cells expressing brain-derived neuro- trophic factor and/or ciliary neurotrophic factor and used them to treat sciatic nerve injury in rats. We observed an increase in sciatic functional index, triceps wet weight recovery rate, myelin thickness, number of myelinated nerve fibers, amplitude of motor-evoked potentials and nerve conduction velocity, and a shortened latency of motor-evoked potentials when al- lografts loaded with both neurotrophic factors were used, compared with allografts loaded with just one factor. Thus, the combination of both brain-derived neurotrophic factor and cili- ary neurotrophic factor-transfected bone marrow mesenchymal stem cells can greatly improve nerve injury. 展开更多
关键词 nerve regeneration peripheral nerve injury brain-derived neurotrophic factor ciliaryneurotrophic factor chemically extracted acellular nerve allografis bone marrow mesenchymal stemcells peripheral nerve neural regeneration
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THE MECHANISM OF ANTITUMOR ACTIVITY OF TOTAL GLUCOSIDES EXTRACTED FROM CYNANCHUM AURICULA-TUM ROYLE (CA) 被引量:1
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作者 胡素坤 赵瑾 +1 位作者 王少君 韩进红 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第1期36-43,共8页
Since the chemical structure of total glucosides from Cynanchum Auriculatum Royle (CA) is similar to that of the steroline of Marsdenia Condurago Reich, a compound which exhibits antitumor activity, research into the ... Since the chemical structure of total glucosides from Cynanchum Auriculatum Royle (CA) is similar to that of the steroline of Marsdenia Condurago Reich, a compound which exhibits antitumor activity, research into the antitumor activity of CA was carried out. Its mechanism of action was studied in vivo with C 57BL/6 mice bearing Lewis lung carcinoma and in vitro, with two mouse tumor cell lines: S180 and EAC. CA inhibited to a certain extent the growth of subcutaneously inoculated Lewis lung carcinoma and its pulmonary metastasis, and augmented the antitumor effect of cyclophosphamide. It showed a killing effect on the EAC and S180 tumor cells of mice in vitro as well. It blocked the tumor cells of solid Lewis lung carcinoma from entering into the S stage from G1 and inhibited DNA synthesis of S180 and EAC tumor cells of mice in vitro. It also markedly increased the number of mononuclear Mφ of tumor bearing mice, stimulated the macrophagic activity of their intraperitoneal Mφ, raised the percentage of ANAE(+) lymphocytes in peripheral blood and enhanced the ABC reaction and antibody formation in tumor bearing mice. 展开更多
关键词 CA THE MECHANISM OF ANTITUMOR ACTIVITY OF TOTAL GLUCOSIDES extracted FROM CYNANCHUM AURICULA-TUM ROYLE
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THE EXTRACTED COMPLEX FORMED BY MONO (2-ETHYLHEXYL)-2-ETHYLHEXYL PHOSPHATE WITH DIVALENT Mn
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作者 HUANG Kelong SHU Wanyin +2 位作者 DING Dunhuang LIU Guogen DONG Ping, Central South University of Technology, Changsha, China HUANG Kelong, Lecturer, Department of Chemistry, Central South University of Technology, Changsha 410083, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第7期16-20,共5页
In order to clarify the mechanism and the complex formed in the extraction of divalent Mn by alkylphosphonic acid monoester, the solid complex has been prepared by mono (2-ethylhexyl)-2-ethylhexyl phosphate, HEH(EH)P,... In order to clarify the mechanism and the complex formed in the extraction of divalent Mn by alkylphosphonic acid monoester, the solid complex has been prepared by mono (2-ethylhexyl)-2-ethylhexyl phosphate, HEH(EH)P, HA with divalent Mn. The elemental analysis, magnetic susceptibility and thermogravimetry have been determined for the solid complex of HEH(EH)P-Mn(II) and the infrared spectrum has been carried out in comparison to the extractant HEH(EH)P. The extracted compound has also been studied by electronic and electron spin resonance spectroscopy in octane solvent and solid state at room temperature. On the basis of the measurements, it is concluded that the structure of the solid polymeric species MnA_2 is in a tetrahedral arrangement. 展开更多
关键词 solvent extraction mono (2-ethylhexyl)-2-ethylhexyl phosphate MN extracted complex
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Apoptosis of neoplasm cell lines induced byhepatic peptides extracted from sucking porcine hepatocytes 被引量:11
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作者 Kong XP Zou QY +3 位作者 Li RB Zheng PL Yang LP Jin SW 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第5期435-439,共5页
关键词 NEOPLASM cell lines APOPTOSIS HEPATIC PEPTIDES HEPATIC extracts liver neoplasms HEPATOCYTES
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Biodegradability of soil water soluble organic carbon extracted from seven different soils 被引量:7
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作者 SCAGLIA Barbara ADANI Fabrizio 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期641-646,共6页
Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WS... Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water (soil/water ratio of 1:2, W/V) for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on the both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, and provided useful information to soil fertility. 展开更多
关键词 biodegradability test cumulated oxygen uptake water extractable organic carbon water soluble organic carbon
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Anti-oxidant and anti-inflammatory activities of ultrasonicassistant extracted polyphenol-rich compounds from Sargassum muticum 被引量:3
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作者 YU Yuan WANG Le +6 位作者 FU Xiaoting WANG Lei FU Xiaodan YANG Min HAN Zhenlian MOU Haijin JEON You-Jin 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第3期836-847,共12页
Polypehnol is an important,potentially bioactive component of Sargassum muticum.In this study,ultrasonic assisted extraction of polyphenol-rich substances was performed using a 38%ethanol solution at a solid:liquid ra... Polypehnol is an important,potentially bioactive component of Sargassum muticum.In this study,ultrasonic assisted extraction of polyphenol-rich substances was performed using a 38%ethanol solution at a solid:liquid ratio of 1:30 at 68℃ for 32min,determined by single-factor and response surface methodology(RSM)optimization.The content of polyphenol was 5.66mg/g in the crude extract.Further extraction showed that the polyphenol mainly distributed in ethyl acetate(SKEE)and water phases(SKEW).The anti-oxidation test by electron spin resonance(ESR)spectrum showed that the SKEE had the strongest scavenging activity on DPPH(1,1-diphenyl-2-picrylhydrazyl)and alkyl radicals.SKEE was shown noncytotoxic but could inhibit the generation of cellular ROS,showing protective effects in H2O2 and AAPHinduced Vero cells and UV-B irradiated HaCaT cells.SKEE also signifi cantly inhibited the release of NO of LPS-induced RAW 264.7 cells.Therefore,the polyphenol-rich extracts in ethanol and ethyl acetate showed excellent anti-oxidant and anti-infl ammatory activities,which is beneficial to the development of high-value bio-substances. 展开更多
关键词 SARGASSUM muticum POLYPHENOL extraction ESR ANTI-OXIDANT ANTI-INFLAMMATORY
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Antibacterial activity of sequentially extracted organic solvent extracts of fruits,flowers and leaves of Lawsonia inermis L.from Jaffna 被引量:3
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作者 E Christy Jeyaseelan S Jenothiny +1 位作者 MK Pathmanathan JP Jeyadevan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第10期798-802,共5页
Objective:To reveal the antibacterial activity of sequentially extracted different cold organic solvent extracts of fruits,flowers and leaves of Lawsonia inermis(L against)some pathogenic bacteria.Methods:Powders of f... Objective:To reveal the antibacterial activity of sequentially extracted different cold organic solvent extracts of fruits,flowers and leaves of Lawsonia inermis(L against)some pathogenic bacteria.Methods:Powders of fruits,flowers and leaves of L inermis were continuously extracted with dichloromethane(DCM),ethyl acetate and ethanol at ambient temperature.The dried extracts were prepared into different concentrations and tested for antibacterial activity by agar well diffusion method,and also the extracts were tested to detennine the available phytochemicals.Results:Except DCM extract of flower all other test extracts revealed inhibitory effect on all tested bacteria and their inhibitory effect differed significantly(P<0.05).The highest inhibitory effect was showed by ethyl acetate extract of flower against Staphylococcus aureus(S.aureus)and Pseudomonas aeruginosa(P.aeruginosa),and ethyl acetate extract of fruit on Escherichia coli(E.coli)and Bacillus subtilis(6.subtilis).The ethyl acetate and ethanol extracts of flower,fruit and leaf expressed inhibition even at 1 mg/100μl against all test bacteria.Among the tested phytochemicals flavonoids were detected in all test extracts except DCM extract of flower.Conclusions:The study demonstrated that the ethyl acetate and ethanol extracts of fruit and flower of L inermis are potentially better source of antibacterial agents compared to leaf extracts of respective solvents. 展开更多
关键词 Lawsonia inermis ANTIBACTERIAL activity SEQUENTIAL extraction Well diffusion method
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Competitive Complexation of Copper and Zinc by Sequentially Extracted Humic Substances from Manure Compost 被引量:4
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作者 LIU Shuai WANG Xu-dong LU Li-lan DIAO Shi-rong ZHANG Jun-feng 《Agricultural Sciences in China》 CAS CSCD 2008年第10期1253-1259,共7页
Chicken manure with similar content of copper and zinc was changes of organic carbon and humus substance complexed chosen to conduct a composting experiment to investigate the copper (HS-Cu) and zinc (HS-Zn), whic... Chicken manure with similar content of copper and zinc was changes of organic carbon and humus substance complexed chosen to conduct a composting experiment to investigate the copper (HS-Cu) and zinc (HS-Zn), which were extracted by water (H2O), sodium hydroxide (NaOH), and sodium pyrophate-NaOH mixture (Na4P2O7-NaOH), sequentially. Distributions of copper and zinc in fulvic acids (FA) and humic acids (HA) in the three extracts were studied. During manure composting, the concentrations of copper and zinc increased from about 500 mg kg^-1 in the raw material to 1 100 mg kg^-1 in the final products. HS-Cu in H2O, NaOH, and Na4P2O7-NaOH extracts occupied 6.7, 26.7, and 19% averagely of total copper and HS-Zn represented 2.7, 13.7, and 17% averagely of total zinc in compost, respectively. In water extracts, both HA and FA mainly complexed with Cu and the mole ratio of Cu to Zn was 2.8 in HA fractions and was 2.6 in FA fractions, respectively. HA mainly complexed with copper, so that the ratios of HA-Cu to HA-Zn averaged 3.4 in NaOH extracts. FA had a similar potential to complex with copper and zinc, so that the ratio of FA-Cu to FA-Zn was close to 1. In Na4P2O7-NaOH extracts, HA or FA had a similar potential to complex with copper and zinc. The ratio of HS-Cu to HS-Zn was close to 1. With manure composting, Na4P2O7-NaOH extractable HS-Zn increased to a level as high as HS-Cu. This indicated that more and more stable complexes of HS-Zn were formed in the late decomposition period. The competition between copper and zinc to be complexed with humic substance became weaker and weaker with the decomposition process. 展开更多
关键词 MANURE copper and zinc decomposition process humic substance sequential extraction
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The pilot test of Pt-Pd and Pt-Rh feeds extracted and separated with a new sulfoxide extractant 被引量:3
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作者 ZHU Ping GU Guobang +2 位作者 QU Zhiping HUANG Yanfei YAO Wenxue 《Rare Metals》 SCIE EI CAS CSCD 2006年第2期99-105,共7页
Platinum, palladium and rhodium of the raw feeds extracted and separated with a new sulfoxide extractant (MSO) were studied in the paper. The pilot test results showed that the percentage extractions are more than 9... Platinum, palladium and rhodium of the raw feeds extracted and separated with a new sulfoxide extractant (MSO) were studied in the paper. The pilot test results showed that the percentage extractions are more than 99% for platinum and palladium in Pt-Pd feed, and the percentage strippings are 100% and 99.2% with HCl and ammonia, respectively. The ratio of palladium to platinum is 0.0016 in stripping platinum solution, and the ratio of platinum to palladium is 0.0020 in stripping palladium solution. The percentage extraction of platinum is 99% in Pt-Rh feed, and the percentage stripping is 100%. The ratio of rhodium to platinum is 0.0002 in stripping platinum solution. Therefore, platinum, palladium, and rhodium feeds are separated effectively with MSO. 展开更多
关键词 solvent extraction pilot test SULFOXIDE platinum group metals
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A NEW DIGITAL MODULATION RECOGNITION METHOD USING FEATURES EXTRACTED FROM GAR MODEL PARAMETERS 被引量:3
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作者 Lu Mingquan Xiao Xianci Li Lemin (University of Electronic Science and Technology of China, Chengdu 610054) 《Journal of Electronics(China)》 1999年第3期244-250,共7页
Based on the features extracted from generalized autoregressive (GAR) model parameters of the received waveform, and the use of multilayer perceptron(MLP) neural network classifier, a new digital modulation recognitio... Based on the features extracted from generalized autoregressive (GAR) model parameters of the received waveform, and the use of multilayer perceptron(MLP) neural network classifier, a new digital modulation recognition method is proposed in this paper. Because of the better noise suppression ability of the GAR model and the powerful pattern classification capacity of the MLP neural network classifier, the new method can significantly improve the recognition performance in lower SNR with better robustness. To assess the performance of the new method, computer simulations are also performed. 展开更多
关键词 MODULATION RECOGNITION GAR model FEATURE extraction NEURAL network CLASSIFIER
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A New Pattern Recognition Method for Detection and Localization of Myocardial Infarction Using T-Wave Integral and Total Integral as Extracted Features from One Cycle of ECG Signal 被引量:5
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作者 Naser Safdarian Nader Jafarnia Dabanloo Gholamreza Attarodi 《Journal of Biomedical Science and Engineering》 2014年第10期818-824,共7页
In this paper we used two new features i.e. T-wave integral and total integral as extracted feature from one cycle of normal and patient ECG signals to detection and localization of myocardial infarction (MI) in left ... In this paper we used two new features i.e. T-wave integral and total integral as extracted feature from one cycle of normal and patient ECG signals to detection and localization of myocardial infarction (MI) in left ventricle of heart. In our previous work we used some features of body surface potential map data for this aim. But we know the standard ECG is more popular, so we focused our detection and localization of MI on standard ECG. We use the T-wave integral because this feature is important impression of T-wave in MI. The second feature in this research is total integral of one ECG cycle, because we believe that the MI affects the morphology of the ECG signal which leads to total integral changes. We used some pattern recognition method such as Artificial Neural Network (ANN) to detect and localize the MI, because this method has very good accuracy for classification of normal signal and abnormal signal. We used one type of Radial Basis Function (RBF) that called Probabilistic Neural Network (PNN) because of its nonlinearity property, and used other classifier such as k-Nearest Neighbors (KNN), Multilayer Perceptron (MLP) and Naive Bayes Classification. We used PhysioNet database as our training and test data. We reached over 76% for accuracy in test data for localization and over 94% for detection of MI. Main advantages of our method are simplicity and its good accuracy. Also we can improve the accuracy of classification by adding more features in this method. A simple method based on using only two features which were extracted from standard ECG is presented and has good accuracy in MI localization. 展开更多
关键词 ECG SIGNAL Classification SIGNAL Processing Myocardial INFARCTION FEATURES Extraction Neural Network
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Organic matter extracted from activated sludge with ammonium hydroxide and its characterization 被引量:1
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作者 Liangliang Wei Kun Wang +3 位作者 Qingliang Zhao Junqiu Jiang Chunmei Xie Wei Qiu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期641-647,共7页
In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated i... In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated into five fractions using XAD-8/XAD-4 resins.Up to a 63.8%-71.1% of organic matter within the sludge could be efficiently extracted by NH 3 ·H 2 O.Fractionation results showed that hydrophobic acid and hydrophilic fraction were two main components among the sludge organic matter (accounting for 32.2% and 48.0% of the bulk organic matter,respectively),whereas transphilic acid,hydrophobic neutral and transphilic neutral were quite low (accounting for 9.2%,5.8% and 4.8%,respectively).Despite that the extractant of NH 3 ·H 2 O showed a relatively higher extraction efficiency of the aromatic components,the relatively low aromaticity of the organic fractions implied that those non-aromatic components could also be effectively extracted,especially for neutral and hydrophilic fractions.In addition,acidic fractions contained more aromatic humic-like components,whereas the neutral fractions had a greater content of aromatic proteins and soluble microbial byproduct-like components.Extraction of sludge organics with NH3·H2O and subsequential fractionation using XAD resins could be a novel method for further characterization of sludge organics. 展开更多
关键词 sludge organic matter extraction FRACTIONATION CHARACTERIZATION
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Comparative Assessment of the Fatty Acid Profiles of Crude Oils Extracted from Seeds of Selected Tea ( Camellia sinensis L.) Cultivars 被引量:2
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作者 Kelvin Omondi George John K. Wanyoko +2 位作者 Thomas Kinyanjui Kelvin O. Moseti Francis N. Wachira 《Food and Nutrition Sciences》 2016年第1期1-7,共7页
Tea seeds resulting from the cultivation of tea in many parts of the world, often regarded as waste, have been found to contain oil of exceptional quality that can be harnessed for use as an oleo-chemical or chemical ... Tea seeds resulting from the cultivation of tea in many parts of the world, often regarded as waste, have been found to contain oil of exceptional quality that can be harnessed for use as an oleo-chemical or chemical intermediate. A comparative study was carried out to examine the free fatty acid profiles of crude oils chemically extracted by Soxhlet extraction from tea seeds collected from different cultivars of Kenyan tea. All the tea seeds of the studied tea cultivars yielded oil, though to different extents (p > 0.05) after the 8-hour extraction. The oils were golden yellow in color. The contents of oleic, linoleic and stearic acids in all the crude test oils have no significant difference (p > 0.05) from each other. However, statistically significant differences (p < 0.05) in the linolenic and palmitic acids contents were evident. Based on the current findings, the test tea oils were predominantly constituted of unsaturated fatty acids, oleic acid being the major unsaturated fatty acid, other fatty acids being present in different but smaller proportions. 展开更多
关键词 Soxhlet Extraction TSO GC FAMEs Clonal Variations
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