147 research outputs found

    Effects of Interaction on Reading Comprehension in the Secondary School Classrooms: An Action Research

    Get PDF
    This study investigates the EFL classrooms to identify the role of interaction in reading comprehension classes Student-student interaction through the form of pairwork was introduced while the pre-test and post-test measured its effect Adequate classes were observed to identify the level of the control group students This study tried to find out the role of interaction in facilitating students reading comprehension It had found that when the students got the opportunity to interact through pair-work they became their source of input And it was evident that after the introduction of interaction their comprehension ability enhanced as they correctly answered more questions in the post-test than in the pre-test Based on the results the study also recommends the introduction of interaction to enhance students skill in listening speaking and writin

    SMART PAYMENTS: METHOD AND SYSTEM FOR INTEGRATING STORED VALUE WALLETS WITH VISA INSTALMENTS SERVICE (VIS)

    Get PDF
    The present disclosure relates to a method and a system for integrating stored value wallets with a Visa Instalments Service (VIS). The present disclosure suggests uploading a Bank Identification Number (BIN) file including BINs eligible for an Equated Monthly Installment (EMI) payment and creating specific plans associated with the uploaded BINs. Thereafter, a cardholder selects a digital wallet which includes a stored value wallet for payment during the checkout process on an electronic commerce (e-commerce) merchant website or a mobile application. Once the selection process is successful, the present disclosure suggests initiating a VIS Application Program Interface (API) to facilitate comprehensive data exchange, wherein data includes, without limited to, primary account number, purchase amount, and wallet amount. After the initiation of the VIS API, the present disclosure suggests determining the best savings EMI plan by combining the VIS API data with an issuer server data. Subsequently, offering/presenting the determined EMI plan along with a suggested down-payment option to the cardholder. Further, the cardholder may actively select the offered EMI plan and proceed to finalize the financial transaction

    Stability of Piceatannol in Dulbecco's Modified Eagle's Medium by In Situ UPLC-MS/MS Analysis

    Get PDF
    Piceatannol is a stilbenoid, which has shown bioactivities in various cell culture models. However, its stability in cell culture medium is not clear. Here, UPLC-MS/MS was applied in situ to analyze the degradation products of piceatannol in Dulbecco's Modified Eagle's Medium (DMEM) and cell culture to investigate the compound's stability in DMEM. During the incubation with cell culture medium (at 4 and 37 °C), several piceatannol derivatives, such as an oxidation product ( m/z 243.06), a reduction product ( m/z 247.09), dimers ( m/z 485.12 and 487.14) and trimers ( m/z 727.18) were detected, which demonstrated the instability of piceatannol in cell culture conditions. To confirm if the new products during the incubation were generated due to the instability of piceatannol, ascorbic acid was added. The presence of ascorbic acid could significantly slow the degradation rate of piceatannol and the generation of piceatannol derivatives, which proved that the new products were generated by the degradation of piceatannol and indicated that the instability of piceatannol might be related to its antioxidant activity

    Highly Oxygenated Flavonoids from the Leaves of Nicotiana plumbaginifolia (Solanaceae)

    Get PDF
    Nicotiana plumbaginifolia Viv. is an annual herb of the family Solanaceae, which grows abundantly in the weedy lands of Bangladesh. This plant possesses analgesic, antibacterial, anti-anxiety and hepatoprotective properties, and produces various phenolic compounds including flavonoids. The present study afforded determination of total phenolic and flavonoid contents, and for the first time, the isolation and characterization of highly oxygenated flavonoids, e.g., 3,3',5,6,7,8-hexamethoxy-4',5'-methylenedioxyflavone (1), 3,3',4',5',5,6,7,8-octamethoxyflavone (2, exoticin), 6,7,4',5'-dimethylenedioxy-3,5,3'-trimethoxyflavone (3) and (3,3',4',5,5',8-hexamethoxy-6,7-methylenedioxyflavone (4) from the leaves of N. plumbaginifolia. All these flavonoids are rather rare natural products, and only found in a few genera, e.g., Polygonum and Murraya. The structures of the isolated flavonoids were elucidated by comprehensive spectroscopic analyses, e.g., UV, 1H, 13C NMR, DEPT, HSQC, HMBC and MS

    Stepwise complexometric determination of aluminium, titanium and iron concentrations in silica sand and allied materials

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>This study aimed at measuring the quantities of Al, Ti and Fe in silica sand and allied materials employing a complexometric method in the same analyte and a stepwise indirect titration with EDTA. The method involves the complexation of Al, Ti and Fe with excess EDTA and the selective de-complexation of TiO-EDTA and Al-EDTA complexes with tartaric acid and NaF respectively. In addition to its simplicity, rapidity and accuracy, the proposed method does not require the use of a separation technique or any sophisticated instrumentation.</p> <p>Results</p> <p>Each of the test samples were analyzed five times using the proposed method. The method's accuracy was confirmed by analyzing the US National Institute of Standards and Technology's (NIST) Standard Reference Materials (SRM) 81a, 89 and IPT SRM 61 using the procedure proposed, in addition to analyzing Ti and Fe levels by spectrophotometry and that of Al by complexometry.</p> <p>Conclusion</p> <p>The study shows that there is good agreement between the proposed and existing methods. The standard deviations of the measurements were calculated by analyzing five replicates of each sample, and were found to be less than 1.5% in our method.</p

    Isolation and Characterization of Antibacterial Compounds from <i>Aspergillus fumigatus:</i> An Endophytic Fungus from a Mangrove Plant of the Sundarbans.

    Get PDF
    The Sundarbans, a UNESCO world heritage site, is one of the largest mangrove forests in one stretch. Mangrove plants from this forest are little studied for their endophytic fungi. In this study, we isolated fourteen endophytic fungi from the plants Ceriops decandra and Avicennia officinalis collected from the Sundarbans. Five of them were identified as Aspergillus sp. and one as Penicillium sp. by macroscopic and microscopic observation. Antibacterial activity of the crude extracts obtained from these endophytes was determined against Staphylococcus aureus, Micrococcus luteus, Escherichia coli, and Pseudomonas aeruginosa using resazurin-based microtiter assay. The isolated endophytes showed varying degrees of antibacterial activity with MICs ranging between 5 and 0.078 mg/mL. Molecular identification of the most active endophyte revealed its identity as Aspergillus fumigatus obtained from the leaves of C. decandra. Acute toxicity study of the ethyl acetate extract of A. fumigatus in mice revealed no mortality even at the highest dose of 2000 mg/kg bodyweight, though some opposing results are found in the subacute toxicity study. The extract was subjected to silica gel and Sephadex column chromatography resulting in the isolation of three pure compounds. LC-MS analysis of these pure compounds revealed their identity as fumigaclavine C, azaspirofuran B, and fraxetin. This is the first report of fraxetin from A. fumigatus. All three identified compounds were previously reported for their antibacterial activity against different strains of both Gram-positive and Gram-negative bacteria. Therefore, the observed antibacterial activity of the ethyl acetate (EtOAc) extract of A. fumigatus could be due to the presence of these compounds. These results support the notion of investigating fungal endophytes from the Sundarbans for new antimicrobial compounds

    GC–MS analysis and pharmacological evaluations of Phoenix sylvestris (Roxb.) seeds provide new insights into the management of oxidative stress and hyperglycemia

    Get PDF
    Phoenix sylvestris Roxb. (Arecaceae) seeds are used in the treatment of diabetes in the traditional system of medicine. The present study evaluated antihyperglycemic and antioxidant activities as well as the total phenolic and flavonoid content of the methanol extract of P. sylvestris seeds (MEPS). The constituents of the extract were identified by GC–MS analysis. MEPS demonstrated strong antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50 = 162.70 ± 14.99 μg) and nitric oxide (NO) (IC50 = 101.56 ± 9.46 μg/ml) free radicals. It also possesses a substantial amount of phenolics and flavonoids. It significantly (p < .05) reduced blood glucose levels in glucose-loaded and alloxan-induced diabetic mice at the doses of 150 and 300 mg/kg b.w., respectively. A total of 46 compounds were detected and identified by gas chromatography–mass spectroscopy (GC–MS) analysis, among which 8-methylisoquinoline N-oxide (32.82%) was predominant. The phytochemical study by GC–MS revealed that the MEPS possesses compounds which could be related to its antidiabetic and antioxidant activities. To recapitulate, P. sylvestris seeds can be a very good option for antidiabetic and antioxidant activity though further studies are still recommended to figure out the responsible phytochemicals and establish their exact mechanism of action

    A systematic review on antioxidant and anti-inflammatory activity of Sesame (Sesamum indicum L.) oil and further confirmation of anti-inflammatory activity by chemical profiling and molecular docking

    Get PDF
    Traditionally sesame oil has been used as a popular food and medicine. The review aims to summarize the antioxidant and anti-inflammatory effects of sesame oil (SO) and its identified compounds as well as further fatty acid profiling and molecular docking study to correlate the interaction of its identified constituents with COX-2. For this, a literature study was made using Google Scholar, Pubmed and SciFinder databases. Literature study demonstrated that SO has potential antioxidant and anti-inflammatory effects in various test systems, including humans, animals and cultured cells through various pathways such as inhibition of COX, non-enzymatic defense mechanism, inhibition of pro-inflammatory cytokines, NF-kB or MAPK signaling and prostaglandin synthesis pathway. Fatty acidanalysis of SO using gas chromatography identified known 9 fatty acids.In-silico study revealed thatsesamin, sesaminol, sesamolin, stigmasterol, Δ5-avenasterol, and Δ7-avenasterol(-9.6 to -10.7 kcal/mol) were the most efficient ligand for interaction and binding with COX-2. The known fatty acid were also showed binding efficiency with COX-2 to some extent (-6.0 to -8.4 kcal/mol).In summary, it is evident that sesame oil may be one of promising traditional medicine that we could use in the prevention and management of diseases associated with oxidative stress and inflammation

    A systematic review on anti-diabetic and cardioprotective effects of gallic acid: A widespread dietary phytoconstituent

    Get PDF
    Gallic acid (GA) is a bioactive phytoconstituent that has been reported to prevent a number of diseases. However, there is no systematic review to-date on its anti-diabetic and cardioprotective potential including molecular mechanisms for such activities. This review aims to summarize the anti-diabetic and cardioprotective effects of GA and further propose a molecular mechanism of its anti-diabetic effects. Accumulation of associated literature was conducted through the use of databases including Google Scholar, PubMed, Web of Science, Science Direct and Scopus databases. Articles published until December 2018 were extracted and all the retracted articles were sorted based on the inclusion and exclusion criteria and relevant articles were further consulted for necessary information. We have found substantial investigations in animals and cultured cells that supports anti-diabetic and cardioprotective effects of GA with several underlying mechanisms including antioxidant enzyme systems and non-enzymatic defense mechanisms. The reported antioxidant activity of GA as well as the modulation of some key proteins linked to diabetes could be a part of the mechanisms by which GA showed anti-diabetic effect. In summary, it is evident that GA is one of the promising dietary phytochemicals that could be beneficial for the treatment and management of diabetes and associated myocardial damage
    • …
    corecore