20 research outputs found

    Slenderness Ratio and Influencing Parameters on the NL Behaviour of RC Shear Wall

    Get PDF
    Shear walls are very efficient structural elements to resist lateral seismic disturbance. Despite the aforementioned seismic performance, recent investigations report that they have suffered from significant structural damage after recent seismic activity, even for those complying with seismic provisions. These deficiencies in resistance and deformation capacities need to be explored. This study considers the influence of plastic length Lp, concrete compressive strength f_c28, longitudinal reinforcement ratio ρl, transverse reinforcement ratio ρsh, reduced axial load ν, confinement zone depth CS and focusing on the geometric slenderness λ. The parametric study has been conducted through NL pushover analysis using Peform3D software. The chosen coupled shear-flexure fiber macro model was calibrated with well-known cyclic experimental specimens. The paper points out the discrepancy between the two well-known codes EC8 and ASCE/SEI 41-13. In fact, the value of the slenderness ratio (λ) that trigger the beginning of a purely flexural behaviour recommended by EC8 (λ>2) is very different from the value of the ASCE/SEI 41-13 (λ>3) without accounting for the effect of the reduced axial force. Finally, it was found that RCW capacities are very sensitive to f_c28, ν, ρl, Lp and less sensitive to ρsh and CS. However, (λ) is the most decisive factor affecting the NL wall response. A new limit of slenderness and appropriate deformations of rotations are recommended to provide an immediate help to designers and an assistance to those involved with drafting codes. Doi: 10.28991/cej-2021-03091777 Full Text: PD

    STR-based genetic structure of the Berber population of Bejaia (Northern Algeria) and its relationships to various ethnic groups

    Get PDF
    Patterns of genetic variation in human populations have been described for decades. However, North Africa has received little attention and Algeria, in particular, is poorly studied, Here we genotyped a Berber-speaking population from Algeria using 15 short tandem repeat (STR) loci D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA from the commercially available AmpF/STR Identifiler kit. Altogether 150 unrelated North Algerian individuals were sampled across 10 administrative regions or towns from the Bejaia Wilaya (administrative district). We found that all of the STR loci met Hardy-Weinberg equilibrium expectations, after Bonferroni correction and that the Berber-speaking population of Bejaia presented a high level of observed heterozygosity for the 15 STR system (>0.7). Genetic parameters of forensic interest such as combined power of discrimination (PD) and combined probability of exclusion (PE) showed values higher than 0.999, suggesting that this set of STRs can be used for forensic studies. Our results were also compared to those published for 42 other human populations analyzed with the same set. We found that the Bejaia sample clustered with several North African populations but that some geographically close populations, including the Berber-speaking Mozabite from Algeria were closer to Near-Eastern populations. While we were able to detect some genetic structure among samples, we found that it was not correlated to language (Berber-speaking versus Arab-speaking) or to geography (east versus west). In other words, no significant genetic differences were found between the Berber-speaking and the Arab-speaking populations of North Africa. The genetic closeness of European, North African and Near-Eastern populations suggest that North Africa should be integrated in models aiming at reconstructing the demographic history of Europe. Similarly, the genetic proximity with sub-Saharan Africa is a reminder of the links that connect all African regions.Instituto Gulbenkian de Ciência, Laboratoire d'Excellence (LABEX) entitled TULIP: (ANR-10-LABX-41)

    Anti-hyperuricemic and neuroprotective effects of Populus nigra L. (Saliacaceae) flower buds used in Algerian folk medicine

    Get PDF
    Context: Populus nigra L., is a species of cottonwood poplar that belongs to the Salicaceae family, is cultivated in multiple areas in Algeria, with an Algerian name of Safsaf. Aims: To evaluate the Populus nigra flower buds extract for its effects on brain modifications against aluminum-induced neurotoxicity in mice. The hypouricemic action of the extract was also evaluated. Methods: To evaluate the effect of extract on AlCl3-induced neurotoxicity on mice a battery of tests was performed to assess a spectrum of learning and memory functions. The hypouricemic action of the extract was studied by the measure of uric acid levels and liver xanthine oxidoreductase activity in normal and hyperuricemic mice. Results: Co-administration of P. nigra extract (200 mg/kg) and AlCl3 (100 mg/kg/day) combined with D-galactose (200 mg/kg/day) during four weeks was found to antagonize the harmful effects of AlCl3 by restoring all the test parameters. Moreover, extract restored the pyramidal cells to near normal in cerebral cortex of mice. Extract, when administered three times orally to the normal and oxonate-induced hyperuricemic mice, was able to elicit significantly hypouricemic effect comparable to that of allopurinol. Conclusions: P. nigra flower buds extract can be considered as food enabling to antagonize AlCl3 toxicity and to control serum uric acid levels

    Acetonic Extract of Buxus sempervirens Induces Cell Cycle Arrest, Apoptosis and Autophagy in Breast Cancer Cells

    Get PDF
    Plants are an invaluable source of potential new anti-cancer drugs. Here, we investigated the cytotoxic activity of the acetonic extract of Buxus sempervirens on five breast cancer cell lines, MCF7, MCF10CA1a and T47D, three aggressive triple positive breast cancer cell lines, and BT-20 and MDA-MB-435, which are triple negative breast cancer cell lines. As a control, MCF10A, a spontaneously immortalized but non-tumoral cell line has been used. The acetonic extract of Buxus sempervirens showed cytotoxic activity towards all the five studied breast cancer cell lines with an IC50 ranging from 7.74 µg/ml to 12.5 µg/ml. Most importantly, the plant extract was less toxic towards MCF10A with an IC50 of 19.24 µg/ml. Fluorescence-activated cell sorting (FACS) analysis showed that the plant extract induced cell death and cell cycle arrest in G0/G1 phase in MCF7, T47D, MCF10CA1a and BT-20 cell lines, concomitant to cyclin D1 downregulation. Application of MCF7 and MCF10CA1a respective IC50 did not show such effects on the control cell line MCF10A. Propidium iodide/Annexin V double staining revealed a pre-apoptotic cell population with extract-treated MCF10CA1a, T47D and BT-20 cells. Transmission electron microscopy analyses indicated the occurrence of autophagy in MCF7 and MCF10CA1a cell lines. Immunofluorescence and Western blot assays confirmed the processing of microtubule-associated protein LC3 in the treated cancer cells. Moreover, we have demonstrated the upregulation of Beclin-1 in these cell lines and downregulation of Survivin and p21. Also, Caspase-3 detection in treated BT-20 and T47D confirmed the occurrence of apoptosis in these cells. Our findings indicate that Buxus sempervirens extract exhibit promising anti-cancer activity by triggering both autophagic cell death and apoptosis, suggesting that this plant may contain potential anti-cancer agents for single or combinatory cancer therapy against breast cancer

    Hepatoprotective and anti-diabetic activities of Fraxinus angustifolia Vahl extracts in animal models: Characterization by HPLC analysis

    Full text link
    Background and aim: The present study was designed to explore anti-diabetic and hepato-protective potentials of Fraxinus angustifolia leaf (FAL) and bark (FAB) extracts in vivo

    An Approach of Diagnosis Based On The Hidden Markov Chains Model

    No full text
    Diagnosis is a key element in industrial system maintenance process performance. A diagnosis tool is proposed allowing the maintenance operators capitalizing on the knowledge of their trade and subdividing it for better performance improvement and intervention effectiveness within the maintenance process service. The Tool is based on the Markov Chain Model and more precisely the Hidden Markov Chains (HMC) which has the system failures determination advantage, taking into account the causal relations, stochastic context modeling of their dynamics and providing a relevant diagnosis help by their ability of dubious information use. Since the FMEA method is a well adapted artificial intelligence field, the modeling with Markov Chains is carried out with its assistance. Recently, a dynamic programming recursive algorithm, called 'Viterbi Algorithm', is being used in the Hidden Markov Chains field. This algorithm provides as input to the HMC a set of system observed effects and generates at exit the various causes having caused the loss from one or several system functions

    Hepatoprotective and antidiabetic effects of Pistacia lentiscus leaf and fruit extracts

    Get PDF
    Pistacia lentiscus (Anacardiaceae) is commonly used in folk medicine to treat various diseases. The aim of the present study was to evaluate the hepatoprotective and antioxidant activities of extracts of P. lentiscus leaves (PL) and fruits (PF) against experimentally induced liver damage. Furthermore, characterization of extracts was attempted by a spectroscopic methodology (Fourier transform infrared spectroscopy) and high-performance liquid chromatography with diode array detection analysis. A hepatoprotective potential against paracetamol [165 mg/kg body weight (b.w.)] toxicity was noticed in mice pretreated with the same dose of PL or PF extract (125 mg/kg b.w.) or a combination of both (PL/PF 63/63 mg/kg b.w.), as revealed by an analysis of biochemical parameters (alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase activities and total bilirubin). These results were confirmed by histological examination of the liver, which revealed significant protection against paracetamol-induced hepatic necrosis. Furthermore, PF extract exhibited a promising antidiabetic activity in streptozotocin-induced diabetic rats, similar to the reference drug glibenclamide (0.91 g/L), a result confirmed by in vitro inhibition of α-amylase. We demonstrated that the leaf crude extract showed the best effect in all tested methods, compared to its fruit counterpart, probably due to the presence of higher amounts of phenolic compounds, as determined by phytochemical and Fourier transform infrared spectroscopy analyses. Moreover, high-performance liquid chromatography with diode array detection led to the identification of six compounds for each part of the plant. Gallic acid, a characteristic compound of Pistacia species, was most abundant in leaves and fruits, while luteolin was detected for the first time in fruits. Obtained activities of P. lentiscus extracts may well be due, at least in part, to the presence of the above compounds

    Antioxidant, cytoprotective, anti-inflammatory and anticancer activities of Pistacia lentiscus (Anacardiaceae) leaf and fruit extracts

    No full text
    International audienceIntroduction : Pistacia lentiscus (Anacardiaceae) is used in Algeria for the treatment of inflammation, burns and gastrointestinal complaints. The present work was designed to establish the rational for the medical use of P. lentiscus, especially to determine the antioxidant, anti-inflammatory, cytoprotective and anticancer activities of leaf and fruit extracts and their fractions.Methods : The antioxidant activity was assessed using the ORAC test, and the cytoprotective effect on H2O2-induced oxidative stress was also investigated. Anti-inflammatory activity was examined by measuring the secretion of interleukin-1β by macrophages exposed to ATP or H2O2. The anticancer potential of the crude extracts against melanoma (B16F10) and mammary (EMT6) cell lines was equally evaluated. UPLC–MS analysis was carried out for compound identification.Results : The crude extracts of leaf and fruit exhibited strong antioxidant activity in the ORAC assay and showed significant cytoprotective effect with maximum protection at 100 μg/mL increasing cell viability by 108.25 ± 1.73 and 104.13 ± 0.97%, respectively. Fractions obtained from fruit extracts were ineffective, while the hydro-alcoholic-eluted fraction 3 of leaf displayed a significant cytoprotective effect. Leaf extract (100 μg/mL) showed significant anti-inflammatory activity, compared to acetylsalicylic acid (ASA). Moreover, leaf and fruit extracts inhibited the growth of B16F10 cells (IC50 = 56.40 and 58.04 μg/mL, respectively). Spectral analysis allowed the identification of six flavonol glycosides and five phenolic acids.Conclusion : Results obtained in this study indicate that P. lentiscus extracts exhibited antioxidant, anti-inflammatory and anticancer properties, in accordance with the traditional uses of the plant

    PEffect of lipid extracts of Nigella sativa L. seeds on the liver ATP reduction and alpha-glucosidase inhibition

    No full text
    Various extracts from the seeds of Nigella sativa have been used in traditional folk medicine to treat inflammation, liver disorders and arthritis. These seeds have been experimentally shown to possess antioxidant and hepatoprotective properties. Beside the hypoglycaemic and hypolipidemic effects, this study was carried out to evaluate, in vitro, toxicological effect of lipid extracts from the Nigella sativa seeds. The tested fractions were: (i) defatted methanolic extract, (ii) total lipid extract obtained by hexane extraction from methanolic extract and (iii) neutral and polar lipid fractions. The fractions were assessed, in vitro, for their inhibitory activity potential on the enzyme alphaglucosidase as suppressing the enzyme activity is one among the therapeutic approaches to attenuate postprandial hyperglycemia. High inhibition of alpha-glucosidase by the two polar lipid fractions (F6 and F7) was reflected by their IC50 (0.51±0.04mg/ml and 0.55±0.09mg/ml, respectively), compared to acarbose (0.53±0.06mg/ml) and thymoquinone (0.65±0.05mg/ml). The hypoglycaemic effect of the polar lipid fraction of Nigella sativa could be explained by the inhibition of alpha-glucosidase, which is one of early steps of carbohydrate metabolism. Toxicological evaluation was investigated on precision-cut rat liver slices (PCLS). On PCLS, lipid extracts reduced ATP levels by 27 to 35%. Results indicate suggest that Nigella sativa extracts don't show a hepatoprotective effect against acetaminophen, but don't exhibit a major hepatotoxicity when tested alone.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
    corecore