In this work, a new numerical technique is proposed for the resolution of a fluid model based on three Boltzmann moments. The main purpose of this technique is to calculate electric and physical properties in the non-...In this work, a new numerical technique is proposed for the resolution of a fluid model based on three Boltzmann moments. The main purpose of this technique is to calculate electric and physical properties in the non-equilibrium electric discharge at low pressure. The transport and Poisson＇s equations form a self-consistent model. This equation system is written in cylindrical coordinates following the geometric shape of a plasma reactor. Our transport equation system is discretized using the finite volume approach and resolved by the N-BEE explicit scheme coupled to the time splitting method. This programming structure reduces computation time considerably. The 2D code is carried out and tested by comparing our results with those found in literature.展开更多
Objective:To screen crude extracts of propolis,bee pollen and honey from four stingless bee species[Trigona incisa(T.incisa)],Timia apicalis,Trigona fuso-baltata and Trigona filscibasis)native to East Kalimantan.Indon...Objective:To screen crude extracts of propolis,bee pollen and honey from four stingless bee species[Trigona incisa(T.incisa)],Timia apicalis,Trigona fuso-baltata and Trigona filscibasis)native to East Kalimantan.Indonesia for cytotoxic activity against five human cancer cell lines(HepG2,SW620,ChaGo-1,KATO-Ⅲand BT474).Methods:All samples were extracted with methanol,and then subpartitioned with n-hexane and ethyl acetate.Each crude extract was screened at 20μg/mL for in vitro cytotoxicity against the cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.Tn addition,four previously shown bioactive components from propolis(apigenin,cafieic acid phenyl ester,kaempferol and naringenin)and two chemotherapeutic drugs(doxorubicin and 5-fluorouracil)were used to evaluate the sensitivity of the cell lines.Results:Overall,crude extracts from propolis and honey had higher cytotoxic activities than bee pollen,but the activity was dependent upon the extraction solvent,bee species and cell line.Propolis extracts from T.incisa and Tarda apicalis showed the highest and lowest cytotoxic activity,respectively.Only the HepG2 cell line was broadly sensitive to the honey extracts.For pure compounds,doxorubicin was the most cytotoxic,the four propolis compounds the least,but the ChaGo-I cell line was sensitive to kaempferol at 10μg/mL and KATO-Ⅲwas sensitive to kaempferol and apigenin at 10μg/mL,.All pure compounds were effective against the BT474 cell line.Conclusions:Propolis from f,incisa and Trigona fusco-balteata contain an in vitro cytotoxic activity against human cancer cell lines.Further study is required,including the isolation and characterization of the active antiproliferative agent(s).展开更多
文摘In this work, a new numerical technique is proposed for the resolution of a fluid model based on three Boltzmann moments. The main purpose of this technique is to calculate electric and physical properties in the non-equilibrium electric discharge at low pressure. The transport and Poisson＇s equations form a self-consistent model. This equation system is written in cylindrical coordinates following the geometric shape of a plasma reactor. Our transport equation system is discretized using the finite volume approach and resolved by the N-BEE explicit scheme coupled to the time splitting method. This programming structure reduces computation time considerably. The 2D code is carried out and tested by comparing our results with those found in literature.
基金Supported by East Kalimantan,Indonesia,the National Research Council of Thailand the Japan Society for the Promotion of Science and the Integrated Innovation Academic Center:HAC Chulalongkorn University Centenary Academic Development Project(Grant No.RES560530041)
文摘Objective:To screen crude extracts of propolis,bee pollen and honey from four stingless bee species[Trigona incisa(T.incisa)],Timia apicalis,Trigona fuso-baltata and Trigona filscibasis)native to East Kalimantan.Indonesia for cytotoxic activity against five human cancer cell lines(HepG2,SW620,ChaGo-1,KATO-Ⅲand BT474).Methods:All samples were extracted with methanol,and then subpartitioned with n-hexane and ethyl acetate.Each crude extract was screened at 20μg/mL for in vitro cytotoxicity against the cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.Tn addition,four previously shown bioactive components from propolis(apigenin,cafieic acid phenyl ester,kaempferol and naringenin)and two chemotherapeutic drugs(doxorubicin and 5-fluorouracil)were used to evaluate the sensitivity of the cell lines.Results:Overall,crude extracts from propolis and honey had higher cytotoxic activities than bee pollen,but the activity was dependent upon the extraction solvent,bee species and cell line.Propolis extracts from T.incisa and Tarda apicalis showed the highest and lowest cytotoxic activity,respectively.Only the HepG2 cell line was broadly sensitive to the honey extracts.For pure compounds,doxorubicin was the most cytotoxic,the four propolis compounds the least,but the ChaGo-I cell line was sensitive to kaempferol at 10μg/mL and KATO-Ⅲwas sensitive to kaempferol and apigenin at 10μg/mL,.All pure compounds were effective against the BT474 cell line.Conclusions:Propolis from f,incisa and Trigona fusco-balteata contain an in vitro cytotoxic activity against human cancer cell lines.Further study is required,including the isolation and characterization of the active antiproliferative agent(s).
