Browsing by Issue Date, starting with "2021-03"
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- Cactus: chemical, nutraceutical composition and potential bio-pharmacological propertiesPublication . Das, Gitishree; Lim, Kyung Jik; Tantengco, Ourlad Alzeus G.; Carag, Harold M.; Goncalves, Sandra; Romano, Anabela; Das, Swagat Kumar; Coy-Barrera, Ericsson; Shin, Han-Seung; Gutierrez-Grijalva, Erick Paul; Heredia, J. Basilio; Patra, Jayanta KumarCactus species are plants that grow in the arid and semiarid regions of the world. They have long fascinated the attention of the scientific community due to their unusual biology. Cactus species are used for a variety of purposes, such as food, fodder, ornamental, and as medicinal plants. In the last regard, they have been used in traditional medicine for eras by the ancient people to cure several diseases. Recent scientific investigations suggest that cactus materials may be used as a source of naturally-occurring products, such as mucilage, fiber, pigments, and antioxidants. For this reason, numerous species under this family are becoming endangered and extinct. This review provides an overview of the habitat, classification, phytochemistry, chemical constituents, extraction and isolation of bioactive compounds, nutritional and pharmacological potential with pre-clinical and clinical studies of different Cactus species. Furthermore, conservation strategies for the ornamental and endangered species have also been discussed.
- Do audit committee characteristics improve financial reporting quality in emerging markets? Evidence from IranPublication . Safari Gerayli, Mehdi; Rezaei Pitenoei, Yasser; Abdollahi, AhmadPurpose The purpose of this study is to investigate the association between certain audit committee characteristics like independence and financial expertise with financial reporting quality (FRQ) of the firms listed on the Tehran Stock Exchange (TSE). Design/methodology/approach The sample includes the 558 firm-year observations from companies listed on the TSE during the years 2012-2017, and the study's hypotheses were tested using multivariate regression model based on panel data. Findings The authors find that audit committee independence has no significant effect on corporate FRQ, whereas audit committee's financial expertise significantly improves firms' FRQ. In other words, higher financial expertise of an audit committee can lead to an increase in its FRQ. The findings of the study are robust to alternate measures of FRQ, individual analysis of the research hypotheses for each year and endogeneity problem. Originality/value To the best of the authors' knowledge, this is the first study to analyze the association between audit committee characteristics and FRQ in emerging capital markets, and so, the findings of the study not only extend the extant theoretical literature concerning the audit committee in developing countries including emerging capital market of Iran but also help investors, managers, capital market regulators, policymakers and audit profession regulators to make informed decisions.
- A decade to study deep-sea lifePublication . Howell, Kerry L.; Hilario, Ana; Allcock, A. Louise; Bailey, David; Baker, Maria; Clark, Malcolm R.; Colaco, Ana; Copley, Jon; Cordes, Erik E.; Danovaro, Roberto; Dissanayake, Awantha; Escobar, Elva; Esquete, Patricia; Gallagher, Austin J.; Gates, Andrew R.; Gaudron, Sylvie M.; German, Christopher R.; Gjerde, Kristina M.; Higgs, Nicholas D.; Le Bris, Nadine; Levin, Lisa A.; Manea, Elisabetta; McClain, Craig; Menot, Lenaick; Mestre, Nélia; Metaxas, Anna; Milligan, Rosanna; Muthumbi, Agnes W. N.; Narayanaswamy, Bhavani E.; Ramalho, Sofia P.; Ramirez-Llodra, Eva; Robson, Laura M.; Rogers, Alex D.; Sellanes, Javier; Sigwart, Julia D.; Sink, Kerry; Snelgrove, Paul V. R.; Stefanoudis, Paris V.; Sumida, Paulo Y.; Taylor, Michelle L.; Thurber, Andrew R.; Vieira, Rui; Watanabe, Hiromi K.; Woodall, Lucy C.; Xavier, Joana R.The United Nations Decade of Ocean Science for Sustainable Development presents an exceptional opportunity to effect positive change in ocean use. We outline what is required of the deep-sea research community to achieve these ambitious objectives.
- Physicochemical characteristics and antiproliferative and antioxidant activities of Moroccan Zantaz honey rich in methyl syringatePublication . Elamine, Youssef; Lyoussi, Badiaa; Miguel, Maria G.; Anjos, Ofelia; Estevinho, Leticia; Alaiz, Manuel; Giron-Calle, Julio; Martin, Jesus; Vioque, JavierZantaz honey is a monofloral variety produced from the melliferous plant Bupleurum spinosum (Apiaceae), a shrub that grows mainly in the Atlas Moroccan Mountains. Determination of the polyphenol composition revealed that methyl syringate accounts for more than 50% of total polyphenols, which represents a very useful parameter for the characterization of this monofloral honey. Epicatechin, syringic acid and catechin are also abundant. Caco-2 and THP-1 cells were used for determination of antioxidant and antiproliferative activities in Zantaz honey, respectively. All six commercial samples that were used for these studies exhibited antioxidant activity and inhibited cell proliferation. Interestingly, these activities had a positive correlation mainly with the content in methyl syringate and gallic acid. The recognition of health promoting activities in Zantaz honey should increase its commercial value, which would have a positive economic impact on the poor rural communities of Morocco where it is produced.
- Independent effects of seawater pH and high P-CO2 on olfactory sensitivity in fish: possible role of carbonic anhydrasePublication . Velez, Zélia; Costa, Rita; Wang, Wenjing; Hubbard, PeterOcean acidificationmay alter olfactory-driven behaviour in fish by direct effects on the peripheral olfactory system; olfactory sensitivity is reduced in CO2-acidified seawater. The current study tested whether this is due to elevated P-CO2 or the consequent reduction in seawater pH and, if the former, the possible involvement of carbonic anhydrase, the enzyme responsible for the hydration of CO2 and production of carbonic acid. Olfactory sensitivity to amino acids was assessed by extracellularmulti-unit recording from the olfactory nerve of the gilthead seabream (Sparus aurata L.) in normal seawater (pH similar to 8.2), and after acute exposure to acidified seawater (pH similar to 7.7) but normal P-CO2 (similar to 340 mu atm) or to high P-CO2 seawater (similar to 1400 mu atm) at normal pH (similar to 8.2). Reduced pH in the absence of elevated P-CO2 caused a reduction in olfactory sensitivity to L-serine, L-leucine, L-arginine and L-glutamine, but not L-glutamic acid. Increased P-CO2 in the absence of changes in pH caused reduced olfactory sensitivity to L-serine, L-leucine and L-arginine, including increases in their threshold of detection, but had no effect on sensitivity to L-glutamine and L-glutamic acid. Inclusion of 1 mmol l(-1) acetazolamide (a membrane-permeant inhibitor of carbonic anhydrase) in the seawater reversed the inhibition of olfactory sensitivity to L-serine caused by high P-CO2. Ocean acidification may reduce olfactory sensitivity by reductions in seawater pH and intracellular pH (of olfactory receptor neurones); the former by reducing odorant-receptor affinity, and the latter by reducing the efficiency of olfactory transduction. The physiological role of carbonic anhydrase in the olfactory receptor neurones remains to be explored.
- Comprehensive metabolomics and lipidomics profiling of prostate cancer tissue reveals metabolic dysregulations associated with disease developmentPublication . Lima, Ana Rita; Carvalho, Márcia; Aveiro, Susana; Melo, Tânia; Domingues, M. Rosário; Macedo-Silva, Catarina; Coimbra, Nuno; Jerónimo, Carmen; Henrique, Rui; Bastos, Maria de Lourdes; Guedes de Pinho, Paula; Pinto, JoanaProstate cancer (PCa) is a global health problem that affects millions of men every year. In the past decade, metabolomics and related subareas, such as lipidomics, have demonstrated an enormous potential to identify novel mechanisms underlying PCa development and progression, providing a good basis for the development of new and more effective therapies and diagnostics. In this study, a multiplatform metabolomics and lipidomics approach, combining untargeted mass spectrometry (MS) and nuclear magnetic resonance (NMR)-based techniques, was applied to PCa tissues to investigate dysregulations associated with PCa development, in a cohort of 40 patients submitted to radical prostatectomy for PCa. Results revealed significant alterations in the levels of 26 metabolites and 21 phospholipid species in PCa tissue compared with adjacent nonmalignant tissue, suggesting dysregulation in 13 metabolic pathways associated with PCa development. The most affected metabolic pathways were amino acid metabolism, nicotinate and nicotinamide metabolism, purine metabolism, and glycerophospholipid metabolism. A clear interconnection between metabolites and phospholipid species participating in these pathways was observed through correlation analysis. Overall, these dysregulations may reflect the reprogramming of metabolic responses to produce high levels of cellular building blocks required for rapid PCa cell proliferation.
- The embodiment of craft production in Bronze Age Portugal: exceptional dental wear grooves in an individual from Monte do Vale do Ouro 2 (Ferreira do Alentejo, Portugal)Publication . Willman, John Charles; Valera, António Carlos; Silva, Ana MariaTwo human lateral mandibular incisors exhibiting exceptional dental wear in the form of lingual surface grooves along the cementoenamel junction were recovered from the superficial levels of a pit grave attributed to the Bronze Age at the archaeological site of Monte do Vale do Ouro 2 (Ferreira do Alentejo, Beja, Portugal). Although a number of analyses of dental wear features acknowledge the relatively common use of the dentition for nondietary purposes (using the 'teeth as tools') during the Early/Middle Bronze Age (2200-1200 BC) of southwest Iberia, the form of dental wear documented at Monte do Vale do Ouro 2 is not only a novel finding in this region but also has seldom been described in any bioarchaeological context. the present study provides a macroscopic and low-magnification description of the atypical dental wear for this individual. Results indicate that the incisors are likely antimeres. In addition to the deep lingual grooves, asymmetrical wear removed a substantial portion of the laterolingual crown volume of each tooth. Occlusal and lingual surface wear accumulated slowly enough for tertiary dentin to form. An occlusal groove is also present on the right I-2. A review of ethnohistoric and bioarchaeological literature suggests that some form of craft production involving the manipulation of cordage or fibre with the mouth and teeth can account for the unique wear patterns from Monte do Vale do Ouro 2. the hand-spinning of flax requires wetting which can be accomplished by passing flax fibres through the mouth in a mediolateral direction while using a hand spindle. Similar habitual behaviours were probably practiced by the Bronze Age individual from Monte do Vale do Ouro 2. the wear grooves represent the embodiment of aspects of craft production and maintenance activities that occurred during this individual's lifecourse.
- Portuguese validation of the brief peer conflict scale: Validity, reliability and invariance across genderPublication . Pechorro, Pedro; Hayes, Nicole; Goncalves, Mariana; Palma, Victor Hugo; Goncalves, Rui Abrunhosa; Marsee, MonicaAggression is a multidimensional construct comprised of different forms and functions, the assessment of which has important implications for understanding externalizing problems in male and female youth. The main aim of the present study is to examine the psychometric properties of a form and function aggression measure, the Brief Peer Conflict Scale 20 (PCS-20) among a community sample of youth (N = 470,M = 15.89 years,SD = 1.00 years) from Portugal, divided into females (n = 213) and males (n = 257). The original four-factor latent structure of the PCS-20 obtained an adequate fit using confirmatory factor analysis, and strong cross gender invariance was demonstrated. The PCS-20 also demonstrated adequate reliability (measured by the Omega and Alpha coefficients), convergent and discriminant validities, criterion validity, and known-groups validity. Our findings support the use of the PCS-20 among Portuguese juveniles as a short measure of the forms and functions of aggression.
- Daily Runoff Forecasting Using a Cascade Long Short-Term Memory Model that Considers Different VariablesPublication . Bai, Yun; Bezak, Nejc; Zeng, Bo; Li, Chuan; Sapac, Klaudija; Zhang, JinAccurate forecasts of daily runoff are essential for facilitating efficient resource planning and management of a hydrological system. In practice, daily runoff is needed for various practical applications and can be predicted using precipitation and evapotranspiration data. To this end, a long short-term memory (LSTM) under a cascade framework (C-LSTM) approach is proposed for forecasting daily runoff. This C-LSTM model is composed of a 2-level forecasting process. (1) In the first level, an LSTM is established to learn the relationship between the precipitation and evapotranspiration at present and to learn several meteorological variables one day in advance. (2) In the second level, an LSTM is constructed to forecast the daily runoff using the historical and simulated precipitation and evapotranspiration data produced by the first LSTM. Through cascade modeling, the complex features of the numerous targets in the different stages can be sufficiently extracted and learned by multiple models in a single framework. In order to evaluate the performance of the C-LSTM approach, four mesoscale sub-catchments of the Ljubljanica River in Slovenia were investigated. The results indicate that based on the root-mean-square error, the Pearson correlation coefficient, and the Nash-Sutcliffe model efficiency coefficient, the proposed model yields better results than two other tested models, including the normal LSTM and other neural network approaches. Based on the results of this study, we conclude that the LSTM under the cascade architecture is a valuable approach and can be regarded as a promising model for forecasting daily runoff.
- Factors influencing firm propensity for ISO 9001 withdrawal: Evidence on decertification tendency and antecedentsPublication . Ferreira, Luís M. F. R.; Cândido, Carlos J. F.There are approximately 1,000,000 ISO 9001 certified companies worldwide. Every year, one third of these companies must decide whether to renew, or not, their certificate. The number of companies that abandon or lose the certificate has been growing and reached an average of 60,000 per year. Considering that there is currently no theory or model to explain this propensity of firms to decertify (18%), the aim of this study is to identify the underlying factors influencing firm propensity for ISO 9001 withdrawal and to analyse the relationships between these factors. In order to achieve these aims, the research develops a structural equation model (PLS-SEM), from extant literature, and estimates the model with survey data from a sample of 221 ISO 9001 certified companies. Results show that the main antecedents to decertification propensity are barriers to the initial certification, (absence of) external certification benefits, decertification motivations, and expected performance after decertification. This is the first study to address decertification from a systemic and comprehensive perspective and to present a structural equation model of the phenomenon. The study makes an integrated contribution to explain decertification propensity with the help of novel research variables. Results suggest several contributions to theory, and practice, and contribute to clarify a major contradiction in the field.