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951.
The artificial bee colony (ABC) algorithm is a popular metaheuristic that was originally conceived for tackling continuous function optimization tasks. Over the last decade, a large number of variants of ABC have been proposed, making it by now a well-studied swarm intelligence algorithm. Typically, in a paper on algorithmic variants of ABC algorithms, one or at most two of its algorithmic components are modified. Possible changes include variations on the search equations, the selection of candidate solutions to be explored, or the adoption of features from other algorithmic techniques. In this article, we propose to follow a different direction and to build a generalized ABC algorithm, which we call ABC-X. ABC-X collects algorithmic components available from known ABC algorithms into a common algorithm framework that allows not only to instantiate known ABC variants but, more importantly, also many ABC algorithm variants that have never been explored before in the literature. Automatic algorithm configuration techniques can generate from this template new ABC variants that perform better than known ABC algorithms, even when their numerical parameters are fine-tuned using the same automatic configuration process. 相似文献
952.
İsmail Yapıcı Ahmet Altay Beyza Öztürk Sarıkaya Mustafa Korkmaz Alptuğ Atila İlhami Gülçin Ekrem Köksal 《化学与生物多样性》2021,18(3):e2000812
In this study, phenolic composition, and in vitro biological activities of ethyl acetate (EAE) and methanol (ME) extracts obtained from the aerial parts of endemic Tanacetum erzincanense were investigated. Total phenolic and flavonoid content of the extracts were determined by Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively. Antioxidant capacity of the extracts was evaluated over radical scavenging (DPPH and ABTS) and metal ion reducing power (FRAP and CUPRAC) tests. Individual phenolic compounds in ME was analyzed by high-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS). Cell inhibitory potential of the extracts was tested against colorectal adenocarcinoma (HT-29), breast adenocarcinoma (MCF-7), and hepatocarcinoma (HepG2) cells by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay. The results showed that ME contains higher TPC (64.4 mg GAE/g) and TFC (62.2 mg QE/g) than those of EAE (41.5 mg GAE/g and 40.0 mg QE/g). LC-ESI-QTOF/MS analysis revealed that ME is rich in phenolic compounds, namely, chlorogenic acid, apigenin, quercetin, luteolin, and diosmetin. Antioxidant assay results indicated that ME possess stronger activity than EAE and a power that competes with synthetic antioxidants. XTT assay results demonstrated that although both extracts displayed a considerable cytotoxicity against the tested cancer cell lines in a time and dose-dependent manner, ME expressed its selective inhibitory action towards MCF-7 cells with an IC50 value of 20.4 μg/mL for 72 h. These results may serve as a basis for further in vivo studies to examine the potential applications of T. erzincanense in food and pharmaceutical industries. 相似文献
953.
Füsun Ertuğ 《Economic botany》2000,54(2):155-182
This study examines both edible plants and non-food uses of plants in a limited area to provide clues for archaeologists, to interpret their findings including the reconstruction of former diets. The results are based on an ethnoarchaeological study conducted in 1994-1995 on the traditional subsistence economy of a contemporary village, in close proximity to a pre-ceramic Neolithic site, A?ikli, in the Aksaray province of Central Anatolia. As a part of this study, about 600 plant specimens were collected, of which over 300 were considered useful by the villagers. Through this study the floral potential of a limited area, and the richness of the traditional knowledge of plants was documented to provide clues to archaeologists, archaeobotanists, botanists, pharmacologists, economists, and perhaps to the planners of future local development projects. 相似文献
954.
To estimate genetic relationships among 46 local grape cultivars, RAPD analysis was performed with 25 decamer primers selected from a total of 60 primers. Genetic relationships among these cultivars were determined by calculating similarity indexes, from which a dendogram was derived. There was high genetic variation among the cultivars, with values of genetic diversity ranging from 0.553 to 0.952 using the Jaccard coefficient. UPGMA analysis of a distance matrix produced a dendogram with six clusters. The relatively high genetic similarity ratios observed for the cultivars was also reflected in the dendogram. In general, no relationship was encountered between the genetic similarity ratios of the cultivars and the results of previous ampelographic analyses. 相似文献
955.
Conversion of olive pomace oil to cocoa butter-like fat in a packed-bed enzyme reactor 总被引:1,自引:0,他引:1
Refined olive pomace oil (ROPO) was utilized as a source oil for production of cocoa butter-like fat. Immobilized sn-1,3 specific lipase catalyzed acidolysis of ROPO with palmitic (PA) and stearic (SA) acids was performed in a laboratory scale packed-bed reactor. Effect of reactor conditions on product formation was studied at various substrate mole ratios (ROPO:PA:SA; 1:1:1, 1:1:3, 1:3:3, 1:2:6), enzyme loads (10%, 20%, 40%), substrate flow rates (1.5, 4.5, 7.5, 15 ml/min) and solvent amounts (150, 400 ml). The highest yield (10.9% POP, 19.7% POS and 11.2% SOS) was obtained at 40% enzyme load, 1:2:6 substrate mole ratio, 45 degrees C, 7.5 ml/min substrate flow rate, 150 ml solvent and 3h reaction time. The melting profile and SFC of the product were comparable to those of CB. Polarized light microscope (PLM) images showed no drastic changes in polymorphic behavior between CB and product. 相似文献
956.
The potential use of the immobilized fresh water algae (in Ca-alginate) of Scenedesmus quadricauda to remove Cu(II), Zn(II) and Ni(II) ions from aqueous solutions was evaluated using Ca-alginate beads as a control system. Ca-alginate beads containing immobilized algae were incubated for the uniform growth at 22 degrees C for 5d ays. Adsorption of Cu(II), Zn(II) and Ni(II) ions on the immobilized algae showed highest values at around pH 5.0. Adsorption of Cu(II), Zn(II) and Ni(II) ions on the immobilized algae increased as the initial concentration of metal ions increased in the medium. The maximum adsorption capacities of the immobilized algal biosorbents for Cu(II), Zn(II) and Ni(II) were 75.6, 55.2 and 30.4 mg/g (or 1.155, 0.933 and 0.465 mmol/g) biosorbent, respectively. When the heavy metal ions were in competition, the amounts of adsorbed metal ions were found to be 0.84 mol/g for Cu(II), 0.59 mol/g for Ni(II) and 0.08 mol/g for Zn(II), the immobilised algal biomass was significantly selective for Cu(II) ions. The adsorption-equilibrium was also represented with Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherms. The adsorption of Cu(II), Zn(II) and Ni(II) ions on the immobilized algae followed second-order kinetic. 相似文献
957.
Chilo iridescent virus (CIV) is the type species for genus Iridovirus, and belongs to the family Iridoviridae. Since the discovery of CIV in 1966, many attempts were made to elucidate the viral genome structure. The virions contain a single linear ds DNA molecule that is circularly permuted and terminally redundant. The genome of CIV has been entirely sequenced. The CIV virion consists of an unusual three-layer structure containing an outer proteinaceous capsid, an intermediate lipid membrane, and a core DNA-protein complex containing the genome. CIV has a broad host spectrum and has, in general, a limited mortality effect on its hosts. Up to now there have been several studies about CIV describing its structure, ecology, and molecular biology. In this review study we present all these studies together to describe the CIV. 相似文献
958.
Ayse Guveli Harry B. G. Ganzeboom Helen Baykara-Krumme Lucinda Platt Şebnem Eroğlu Niels Spierings 《Ethnic and racial studies》2017,40(14):2558-2576
Despite recent advances, critical areas in the analysis of European migration remain underdeveloped. We have only a limited understanding of the consequences of migration for migrants and their descendants, relative to staying behind; and our insights of intergenerational transmission is limited to two generations of those living in the destination countries. These limitations stem from a paucity of studies that incorporate comparison with non-migrants – and return migrants – in countries of origin and which trace processes of intergenerational transmission over multiple generations. This paper outlines the theoretical and methodological discussions in the field, design and data of the 2,000 Families study. The study comprises almost 50,000 members of migrant and non-migrant Turkish families across three family generations, living in Turkey and eight European countries. We provide indicative findings from the study, framed within a theoretical perspective of “dissimilation” from origins, and reflect on its potential for future migration research. 相似文献
959.
In the present work, simple and sensitive extraction methods for selective determination of manganese have been successfully developed. The methods were based on solubilization of manganese in deep eutectic solvent medium. Three deep eutectic solvents with choline chloride (vitamin B4) and tartaric/oxalic/citric acids have been prepared. Extraction parameters were optimized with using standard reference material (1573a tomato leaves). The quantitative recovery values were obtained with 1.25 g/L sample to deep eutectic solvent (DES) volume, at 95 °C for 2 h. The limit of detection was found as 0.50, 0.34, and 1.23 μg/L for DES/tartaric, DES/oxalic, and DES/citric acid, respectively. At optimum conditions, the analytical signal was linear for the range of 10–3000 μg/L for all studied DESs with the correlation coefficient >0.99. The extraction methods were applied to different real samples such as basil herb, spinach, dill, and cucumber barks. The known amount of manganese was spiked to samples, and good recovery results were obtained. 相似文献
960.