68 research outputs found

    Attitudes towards science among senior secondary students in Fiji

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    In order to investigate gender and ethnicity-based differences in scientific attitudes among Fijian students, the widely studied Test of Scientific Related Attitudes (TOSRA) was administered to 1401 senior secondary Fijian students (Years 11–13; approximately 15–18 years of age). Students generally had a positive attitude towards science overall in Years 11–13, with females showing a more positive attitude than males. By Year 13, the attitudes of females towards science had become more negative. The attitude of iTaukei students towards science started out lower than other ethnicities in Year 11 and increased during Year 12, before falling to below the starting attitude levels in Year 13. Fijian students of Indian descent generally had a positive attitude towards science that remained consistent throughout Years 11–13, with an increase in leisure and career interest in science in Year 13. A strong correlation was found between the ethnicity of a student and their first language. Continued science outreach programmes, particularly in Year 12, are important to achieve and retain scientific interest and attitudes among Fijian secondary students. © 2020, Wilf Malcolm Institute of Educational Research. All rights reserved

    Sewage sludge heavy metal analysis and agricultural prospects for Fiji

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    Insoluble residues produced in Waste Water Treatment Plants (WWTP) as by products are known as sewage sludge (SS). Land application of SS, particularly in agricultural lands, is becoming an alternative disposal method in Fiji. However, currently there is no legislative framework governing its use. SS together with its high nutrient and organic matter contents, constitutes some undesired pollutants such as heavy metals, which may limit its extensive use. The focus of this study therefore was to determine the total concentrations of Pb, Zn, Cd, Cu, Cr, Ni and Mn in the SS produced at the Kinoya WWTP (Fiji) and in the non-fertile soil amended with the SS at 20, 40, 60, 80% application rates and in the control (100% Soil). The bioavailable heavy metals were also determined as it depicts the true extent of metal contamination. The treatment mixtures were then used to cultivate cabbage plants in which the total heavy metal uptake was investigated. Total Zn (695.6 mg/kg) was present in the highest amounts in the 100% SS (control), followed by Pb (370.9 mg/kg), Mn (35.0 mg/kg), Cu (65.5 mg/kg), Cr (20.5 mg/kg) and finally Cd (13.5 mg/kg) and hence a similar trend was seen in all treatment mixtures. The potential mobility of sludgeborne heavy metals can be classified as Ni > Cu > Cd > Zn > Mn > Cr > Pb. Total metal uptake in plant leaves and stems showed only the bioavailable metals Cu, Cd, Zn and Mn, with maximum uptake occurring in the leaves. Ni, despite being highly mobile was not detected, due to minute concentrations in the SS treatments. Optimum growth occurred in the 20 and 40% SS treatments. However maximum Cu and Mn uptake occurred in the 40% SS treatment thereby making the 20% treatment the most feasible. Furthermore the total and bioavailable metal concentrations observed were within the safe and permitted limits of the EEC and USEPA legislations

    Attitude and achievement of first-year chemistry undergraduate students at the university of the South Pacific

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    Student attitude toward chemistry may influence engagement and achievement in chemistry-related courses, however, equivocal results in studies conducted in Western countries to date indicate this relationship requires further investigation. In this study, we investigated the correlation between attitude toward chemistry and achievement amongst a cohort of first-year undergraduate students from The University of the South Pacific (USP). A cluster analysis was used to identify low- and high-achieving groups of students to further explore potential correlations. There was a positive correlation between the cognitive and affective components of attitude among low-achieving students, but not among high-achieving students. The cognitive component of attitude did not appear to be strongly correlated with achievement in students from either group, although the affective component was positively correlated with achievement. The single item most strongly correlated with student achievement was their response on the Worthless-Beneficial scale. One of the notable findings was the differences in the attitude-achievement relationship between low-achieving and high-achieving students, suggesting that combining these clusters of students into a single group for analysis may obscure underlying correlations. Chemistry educators should continue to target their teaching styles to cater to different learning styles and achievement levels of students, including cognitive and non-cognitive learning styles. Copyright © 2022 Johnson, Reddy, Sharma, Wakeling, Mani, Benveniste, Naiker and Brown

    Australian ethnomedicinal plant extracts promote apoptosis-mediated cell death In human hepatocellular carcinoma in vitro

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    Introduction: Hepatocellular carcinoma (HCC) Is the leading cause of primary liver cancer with Its prevalence continuing to rise. Although the number of cases continues to rise In both developing and developed countries, prognosis remains poor due to a lack of successful treatments. Inspired by the prospect of developing complementary medicines for this condition, we explore several native Australian plants for anti-carcinogenic activity, especially against HCC. Methods: Cytotoxicity assays against HCC cell lines were conducted using various plant extracts. Biochemical profiling of the plant species was conducted for total phenolics and antioxidant capacity, while reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the active apoptotic pathways. Results: Westringia fruticosa and Prostanthera ovalifolia (small-leaved variety) had high antioxidant (410 and 227 mg/g, respectively) and phenolic contents (72.7 and 42.7 mg/g, respectively). P ovalifolia (small-leaved variety) demonstrated the greatest cytotoxic activity against HepG2 cells (IC50 4.61 ± 0.98 pg/mL) followed by Solanum laciniatum leaves (11.79 ± 0.43 pg/mL) and fruit extracts (ripe, unripe) (14.85 ± 1.80 and 19 ± 1.32 pg/mL, respectively). RT-PCR results confirmed apoptotic events in HepG2 cells, exposed to ripe and unripe S. laciniatum fruit extracts, via caspase-3 pathway. The highest apoptotic induction occurred after 8 hr. Compared to unripe fruits, ripe fruits induced a greater level of apoptosis, as evidenced by a 73 % higher level of caspase-3 mRNA expression and 22 % lower IC50 value. Conclusion: With further investigation, these fruits may provide a valuable source of anticarcinogenic compounds for use as chemotherapeutic or complementary therapies

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Phytochemical and Bioassay Dataset

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    Phytochemistry: Phytochemical assays, HPLC phenolic profile, LC-MS/MS data, and GC-MS data. Bioassays: Anticancer and antimicrobial bioassays.</p

    An Analysis of Commercial Noni Juice: LC-MS/MS Phenolic Profiles and Cytotoxic Activity

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    Fermented juice from the noni tree (Morinda citrifolia) is a traditional medicinal product used by South Pacific Islanders to treat a wide range of ailments, including cancer, inflammation and obesity, as well as improving overall wellbeing. Many of its bioactive properties have been suggested to arise from the high antioxidant capacity and phenolic content found in the juice. However, there have been limited investigations into the phenolic profiles of noni juice produced locally in the Pacific. This study aimed to investigate the chemical composition and bioactive properties of noni juice. The first phase of this study used liquid chromatography with tandem mass spectrometry (LC-MS/MS) to characterise the phenolic composition of five brands of commercial noni juice produced in the South Pacific region. A total of 21 phenolic compounds were putatively identified, with the most abundant generally being rutin, 4-hydroxybenzoic acid and gentisic acid. Vastly differing phenolic profiles were found between the noni juice brands. Significant differences were also found in their antioxidant capacities and total phenolic contents. Of the three major phenolic compounds identified, gentisic acid showed the highest antioxidant activity (640% higher than Trolox). Additionally, the noni juice showed no significant anti-acetylcholinesterase activity and no to moderate cytotoxicity against two cancer cell lines (HeLa and HT29). These results indicate that the phytochemical profiles&mdash;and hence, the expected bioactive properties&mdash;are likely to vary significantly between different noni juice brands. Furthermore, the anti-cancer activity of non-concentrated noni juice appears to be relatively low

    Potential for Fourier transform infrared (FTIR) spectroscopy toward predicting antioxidant and phenolic contents in powdered plant matrices

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    Mid-infrared spectroscopy is finding an increasing number of applications; however, many of its potential uses remain unexplored. In this study, mid-infrared spectroscopy is applied to predict total antioxidant capacity and phenolic contents of powdered matrices of 14 diverse plant species. In all instances, the optimum prediction models were found using standard normal variate smoothing as a pre-processing method. The results show high correlation between the FTIR predicted and chemically determined values, namely R2 values of 0.962 for total phenolics, 0.829 for cupric reducing antioxidant potential (CUPRAC) and 0.911 for ferric reducing antioxidant potential (FRAP). The relative RMSE found for validation indicated that total phenolic content could be predicted with higher accuracy than CUPRAC or FRAP. This pilot study highlights the promise of this technology for plant breeders and a range of industries where rapid screening of many samples for antioxidant and/or phenolic content is envisaged

    Correlations between Capsaicin, Dihydrocapsaicin and Phenolic Content in Habanero Chillies

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    Australia is a minor producer of chilli, with the industry producing around 2500 tonnes of chillies per year. Due to the small size of the industry, there is currently limited research on the typical levels of capsaicinoids in the Australian crop and the relationship between these constituents and other agronomic and nutritional factors. This study applied a rapid, maceration-based extraction protocol with end-over-end shaking, coupled with a HPLC-DAD method for the analysis of capsaicin and dihydrocapsaicin in 20 Habanero chilli samples from Queensland, Australia. All samples were from the same growing season (2020) but were taken from different within-field locations to ensure that all of the variability within the growing site was sampled. In addition to the capsaicinoid measurements, the total phenolic content was measured using the Folin-Ciocalteu assay, while antioxidant activity was measured using the Ferric Reducing Antioxidant Power (FRAP) method. The capsaicin concentration of the samples ranged from 1474&ndash;3916 mg/kg, while the dihydrocapsaicin content ranged between 638&ndash;1757 mg/kg, giving total pungencies of approximately 32,000 to 83,000 Scoville Heat Units. Similarly, the total phenolic content varied from 1000&ndash;1608 mg gallic acid equivalents/100 g, while the antioxidant activity ranged from 301 to 455 mg Trolox equivalents/100 g. Pearson linear correlation analysis revealed that the capsaicin and dihydrocapsaicin contents were strongly positively correlated with one another (R2 = 0.73; p &lt; 0.001), with a mean capsaicin: dihydrocapsaicin ratio of 2.4:1. Furthermore, there was a moderate positive correlation between the total capsaicinoid content and total phenolic content of the samples (R2 = 0.58; p &lt; 0.01), as well as a strong correlation between the total capsaicinoid content and FRAP (R2 = 0.81; p &lt; 0.001). However, dry matter content was not significantly correlated with capsaicinoid content, total phenolic content or antioxidant activity (p &gt; 0.05 for all). These results may be used to inform future breeding programs for high-capsaicin chilli varieties and support further research into the agronomic and genetic factors driving capsaicin and dihydrocapsaicin content

    The Phytochemistry and Anticarcinogenic Activity of Noni Juice

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    Noni juice, obtained from the fruit of the noni tree (Morinda citrifolia L.), is a popular commodity in the market, particularly in the South Pacific. It is widely used by consumers for the prevention of several lifestyle diseases. Although there is increasing interest in the potential therapeutic use of noni plants, there are no comparative studies on the various commercialized noni fruit juices available to decipher their phytochemical composition and properties against carcinomas. The present study, therefore, aims to fill this research gap and investigate the juice&rsquo;s anecdotal use as complementary alternative medicine to manage cancer. Five commercial brands of noni juice were included in this study, namely, Tahitian Organic Noni (TON), Cook Island Noni (CIN), Dynamic Health Noni (DHN), Fijian Noni (FN), and Life Health Noni (LHN). The juice samples were vacuum-filtered and freeze-dried to obtain crystal products for methanolic extraction. Total phenolic content (TPC) and antioxidant capacity (FRAP&mdash;ferric reducing antioxidant power) were determined on the methanolic extracts. The cytotoxicity of the noni juices was also tested on human cervical adenocarcinoma (HeLa cell lines) by dissolving 2 mg of the crystal product in sterile deionized water and diluting to 1000 &mu;g/mL in the media culture. The final concentration of the extracts in the well plate was 500 &mu;g/mL. The MTS cell viability assay was performed after the cells were incubated with the extracts for 48 h at 37 &deg;C with 5% CO2. The DHN and FN extracts were found to have the highest TPC of 5393 &plusmn; 298 and 5060 &plusmn; 23 mg gallic acid equivalent /100 g dry weight (DW), respectively, whereas the highest antioxidant capacity was seen in the CIN extract (6389 &plusmn; 49 mg Trolox equivalent/100 g DW). The CIN extract also showed the most promising effect with only 63 &plusmn; 1% cell viability, whilst the other extracts showed lower cytotoxic effects (76&ndash;90% cell viability) on the HeLa cell line. It is possible that greater cytotoxicity could be observed over long exposure times. The noni juice samples contain high levels of TP and antioxidant capacity and appear to show some level of cytotoxic activity, which were statistically different from the negative control. Further work involving more extensive in vitro and in vivo studies are necessary to elucidate its anticarcinogenic activities
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