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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:4
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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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Effect of Allelochemicals of Chinese-fir root extracted by supercritical CO_2 extraction on Chinese fir 被引量:9
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作者 林思祖 曹光球 +1 位作者 杜玲 王爱萍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期122-126,共5页
Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of se... Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of seed germination. The results showed thatas to the available rate of allelochemicals, the pressure and temperature of extraction were themost important factors. The allelochemicals of Chinese-fir root extracted by pure CO_2 and ethanolmixed with CO_2 have different allelopathic activities to seed germination, and the allelochemicalsextracted by ethanol mixed with CO_2 had stronger inhibitory effects on seed germination than thatextracted by pure CO_2. 展开更多
关键词 chinese fir autointoxication supercritical CO_2 extraction BIOASSAY SEEDGERMINATION
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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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Study on Tanshinone Extracted from Salvia miltiorrhiza Bge. Dregs 被引量:2
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作者 石岭 鱼红闪 金凤燮 《Agricultural Science & Technology》 CAS 2010年第1期103-106,共4页
[Objective]The aim was to extract tanshinone from Salvia miltiorrhiza Bge. dregs and to determine tanshinone components. [Method]Organic solvent method was adopted to extract tanshinone from S. miltiorrhiza dregs and ... [Objective]The aim was to extract tanshinone from Salvia miltiorrhiza Bge. dregs and to determine tanshinone components. [Method]Organic solvent method was adopted to extract tanshinone from S. miltiorrhiza dregs and TLC was used to determine the optimum extraction solvent. The components of tanshinone were measured with HPLC. [Result]Ether was the best solvent to extract tanshinone from S. miltiorrhiza dregs. After water immersion,dry dregs of S. miltiorrhiza and Panax notoginseng were extracted with ethanol to obtain fat-soluble extracts. Then with ether as the solvent for Soxhlet extraction,the yield of crude tanshinone was 2.17%. The HPLC detection showed that the contents of tanshinone Ⅱ A,methylene tanshinquinone,cryptotanshinone,tanshinone Ⅰ were 3.62%,1.02%,2.56%,2.75% respectively. [Conclusion]The components of tanshinone in S. miltiorrhiza dregs were basically the same as tanshinone in medicine S. miltiorrhiza. S. miltiorrhiza dregs could be used as a kind of tanshinone resource,which has the value of development and utilization. 展开更多
关键词 Salvia miltiorrhiza Bge. dregs TANSHINONE EXTRACTION
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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:7
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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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Oral immune regulation using colitis extracted proteins for treatment of Crohn's disease: Results of a phase Ⅰ clinical trial 被引量:8
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作者 Eran Israeli Eran Goldin +5 位作者 Oren Shibolet Athalia Klein Nilla Hemed Dean Engelhardt Elazar Rabbani Yaron Ilan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第20期3105-3111,共7页
AIM: To evaluate safety and possible efficacy of induction of oral immune regulation using colitis extracted proteins (CEP) in Crohn's disease (CD) subjects. METHODS: Ten CDs were treated orally with autologous CE... AIM: To evaluate safety and possible efficacy of induction of oral immune regulation using colitis extracted proteins (CEP) in Crohn's disease (CD) subjects. METHODS: Ten CDs were treated orally with autologous CEP thrice weekly for 16 wk. Subjects were monitored for CDAI and IBDQ. Immune modulatory effect was assessed by T-lymphocyte FACS analysis, CEP-specific IFNγ ELISPOT assay and cytokine levels. RESULTS: Induction of oral immune regulation significantly ameliorated disease activity. All (10/10) subjects had clinical response (CDAI≤70) and 7/10 achieved clinical remission (CDAI≤150). Significant increase in mean IBDQ score was noted (134±9 vs 164±12). No treatment-related adverse events were noted. High levels of CEP-specific IFNγ spot forming colonies were detected in five subjects prior to treatment and in all five, a marked decrease was observed. The CD4+/CD8+ lymphocyte ratio and peripheral NKT cell numbers increased significantly, in 7/10 and in 5/10 subjects, respectively. Significant increase in serum IL-10 and IL-4 levels was observed in 7/10 subjects during treatment period. CONCLUSION: Immune regulation via oral administration of CEP is a safe and possibly effective treatment for subjects with moderate CD and may provide means of antigen-specific immune modulation. 展开更多
关键词 Crohn's disease Colitis extracted proteins
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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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Effect of Allelochemicals of Chinese-fir root extracted by supercritical CO2 extraction on Chinese fir 被引量:5
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作者 林思祖 曹光球 +1 位作者 杜玲 王爱萍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期122-126,185-186,共页
Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of s... Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of seed germination. The results showed that as to the available rate of allelochemicals, the pressure and temperature of extraction were the most important factors. The allelochemicals of Chinese-fir root extracted by pure CO2 and ethanol mixed with CO2 have different allelopathic activities to seed germination, and the allelochemicals extracted by ethanol mixed with CO2 had stronger inhibitory effects on seed germination than that extracted by pure CO2. 展开更多
关键词 Chinese fir Autointoxication Supercritical CO2 extraction BIOASSAY Seed germination
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Acid volatile sulfide and simultaneously extracted metals in superficial sediments from Baihua Lake, China
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作者 章吉萍 胡继伟 +4 位作者 黄先飞 沈威 金梅 付丽亚 靳小飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1079-1087,共9页
The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs... The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs) to acid volatile sulfide (AVS). Atomic absorption spectrometry (AAS) and X-ray powder diffraction (XRD) were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g (dry weight). The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake. 展开更多
关键词 Baihua Lake SEDIMENTS acid volatile sulfides simultaneously extracted metals BIOAVAILABILITY
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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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Hot water-extracted Lycium barbarum and Rehmannia glutinosa inhibit proliferation and induce apoptosis of hepatocellular carcinoma cells 被引量:31
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作者 Jane C-J Chao Shih-Wen Chiang +2 位作者 Ching-Chiung Wang Ya-Hui Tsai Ming-Shun Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第28期4478-4484,共7页
AIM: To investigate the effect of hot water-extracted Lydurn barbarum (LBE) and Rehrnannia glutinosa (RGE) on cell proliferation and apoptosis in rat and/or human hepatocellular carcinoma (HCC) cells. METHODS:... AIM: To investigate the effect of hot water-extracted Lydurn barbarum (LBE) and Rehrnannia glutinosa (RGE) on cell proliferation and apoptosis in rat and/or human hepatocellular carcinoma (HCC) cells. METHODS: Rat (H-4-Ⅱ-E) and human HCC (HA22T/ VGH) cell lines were incubated with various concentrations (0-10 g/L) of hot water-extracted LBE and RGE. After 6-24 h incubation, cell proliferation (n = 6) was measured by a colorimetric method. The apoptotic cells (n = 6) were detected by flow cytometry. The expression of p53 protein (n = 3) was determined by SDS-PAGE and Western blotting. RESULTS: Crude LBE (2-5 g/L) and RGE (2-10 g/L) dose-dependently inhibited proliferation of H-4-Ⅱ-E cells by 11% (P 〈 0.05) to 85% (P 〈 0.01) after 6-24 h treatment. Crude LBE at a dose of 5 g/L suppressed cell proliferation of H-4-Ⅱ-E cells more effectively than crude RGE after 6-24 h incubation (P 〈 0.01). Crude LBE (2-10 g/L) and RGE (2-5 g/L) also dose-dependently inhibited proliferation of HA22T/VGH cells by 14%-43% (P 〈 0.01) after 24 h. Crude LBE at a dose of 10 g/L inhibited the proliferation of HA22T/VGH cells more effectively than crude RGE (56.8% + 1.6% vs 70.3% + 3.1% of control, P = 0.0003 〈 0.01). The apoptotic cells significantly increased in H-4-Ⅱ-E cells after 24 h treatment with higher doses of crude LBE (2-5 g/L) and RGE (5-10 g/L) (P 〈 0.01). The expression of p53 protein in H-4-Ⅱ-E cells was 119% and 143% of the control group compared with the LBE-treated (2, 5 g/L) groups, and 110% and 132% of the control group compared with the RGE -treated (5, 10 g/L) groups after 24 h. CONCLUSION: Hot water-extracted crude LBE (2-5 g/L) and RGE (5-10 g/L) inhibit proliferation and stimulate p53-mediated apoptosis in HCC cells. 展开更多
关键词 Lycium barbarum extract Rehmannia glutinosa extract PROLIFERATION APOPTOSIS Hepatocellular carcinoma
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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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