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MAKALUVAMINES AS CHITINASE INHIBITORS ISOLATED FROM AN ASCIDIAN OF THE GREAT BARRIER REEF
Get PDFThis thesis investigates the secondary metabolites isolated from a marine tunicate species of the Great Barrier Reef, Australia. Structural elucidation techniques led to the identification of at least two known compounds belonging to a family of secondary metabolites more commonly isolated from marine sponges. One of the isolated compounds, Makaluvamine H, was used in a preliminary enzyme kinetics assay to assess potential inhibitive properties against chitinase. Additional Makaluvamine compounds from previous studies were obtained and assessed in this assay. This included a purified sample of Makaluvamine P, which was one of the two known compounds isolated and identified from the sample of this investigation. The findings of this research demonstrate that the Makaluvamine compounds assessed do possess inhibitive properties against Streptomyces chitinase enzyme. Makaluvamine A demonstrated the highest level of biological activity against the Streptomyces chitinase enzyme, with inhibition observed at a molar concentration of 12.4 μM. The lowest molar concentration at which inhibition was observed for the other Makaluvamine compounds were as follows; Makaluvamine P (15.4 μM), Makaluvamine H (23.1 μM) and Makaluvamine C (117 μM). Further investigation into the inhibitive properties of these compounds could potentially lead to their application in commercial sectors such as agriculture and healthcare
Uneven second language competency in the English for Academic Purposes context: ‘spiky profiles’ and the role of self-efficacy beliefs
Get PDFUneven language competency has been documented in multiple educational contexts with authors alluding to the ‘spiky profiles’ of English second language [L2] learners. These accounts have thus far been anecdotal, so this mixed-method study contributes original empirical research into the competency profiles and the self-efficacy [SE] beliefs of English for Academic Purposes [EAP] students in the UK Higher Education [HE] context. It is crucial to identify and treat ‘spiky profiles’ where they occur due to the considerable language demands of tertiary study, moreover, understanding the SE beliefs that accompany students’ profiles further informs EAP teaching approaches.
In the study’s quantitative phase, 2114 sets of test scores from the skill areas of speaking, listening, reading, and writing, were collected from students with varying first languages [L1s] from six sittings of a B2 English language test between December 2016 and September 2019. An innovative approach measured these students’ degree of uneven competency, and their score sets were profiled. Correlational and standard multiple regression analyses were conducted, as were t-testing of profiles and ANOVA of three L1 groupings. In the qualitative phase, interviews elicited fifteen students’ SE beliefs vis-à-vis their competency profiles. Bandura’s (1997) model of self-efficacy underpinned the interview guide, but open coding and thematic analysis allowed new themes to emerge.
The unique contribution of this study is evidence that uneven competency is very common and patterned. Many students exhibited an uneven profile, with one third of the sample scoring highest in speaking, followed by listening, reading, and writing. Significant differences according to L1 were identified with L1 Arabic students being more unevenly competent. The qualitative findings uncovered SE’s self-regulatory and motivational impacts on L2 development. Differing beliefs across skill areas were implicated in differing reports of self-regulation, motivation, and ensuing language performance via negative, resilient, and positive feedback loops.
Both phases of the study highlighted the importance of the productive skills in students’ profiles. The disparities observed were explained by the influence of students’ L1s and educational experiences, as well as students’ conceptions and expectations of these skills areas. It is argued that closing the gap between the speaking and writing competencies of UK EAP students can be achieved through process-genre instruction that incorporates careful management of students’ SE beliefs
Music and dance in the service of modern Poland in Polish films of the 1930s
No full textThis chapter discusses the role of music, dance and sound technologies in Polish romantic comedies of the 1930s: Piętro wyżej ([One Floor Above], dir. Leon Trystan, 1937), Paweł i Gaweł ([Paweł and Gaweł], dir. Mieczysław Krawicz, 1938), Zapomniana melodia ([Forgotten Melody], dir. Konrad Tom and Jan Fethke, 1938) and Będzie lepiej ([Things Will Get Better], dir. Michał Waszyński, 1936). It argues that in these films music and sound serve the main narrative about love and are used to show Polish modernisation during this period by including the motif of the radio. Utopianism is juxtaposed with an affirmation of the political and economic status quo
Trust Us—We Are the (COVID-19 Misinformation) Experts: A Critical Scoping Review of Expert Meanings of “Misinformation” in the Covid Era
Get PDFSince the WHO declared COVID-19 a pandemic, prominent social actors and institutions have warned about the threat of misinformation, calling for policy action to address it. However, neither the premises underlying expert claims nor the standards to separate truth from falsehood have been appraised. We conducted a scoping review of the medical and social scientific literature, informed by a critical policy analysis approach, examining what this literature means by misinformation. We searched academic databases and refereed publications, selecting a total of 68 articles for review. Two researchers independently charted the data. Our most salient finding was that verifiability relied largely on the claims of epistemic authorities, albeit only those vetted by the establishment, to the exclusion of independent evidentiary standards or heterodox perspectives. Further, “epistemic authority” did not depend necessarily on subject matter expertise, but largely on a new type of “expertise”: in misinformation itself. Finally, policy solutions to the alleged threat that misinformation poses to democracy and human rights called for suppressing unverified information and debate unmanaged by establishment approved experts, in the name of protecting democracy and rights, contrary to democratic practice and respect for human rights. Notably, we identified no pockets of resistance to these dominant meanings and uses. We assessed the implications of our findings for democratic public policy, and for fundamental rights and freedoms
Resistance to Tyranny versus the Public Good: John Locke and Counter-Terror Law in the United Kingdom
Get PDFJohn Locke was a social contract theorist. He envisaged that individuals had domiciled in a state of nature, enjoying natural rights. But because of the insecurities of the natural state, individuals transitioned to the stability of civil society, guaranteed by a sovereign. There were fetters on the sovereign, however, such as passing laws for the public good. Is modern legislation to counter terrorism for the public good? Locke also expressly granted a right of resistance on the people. But is this right terrorism? Reflecting on these principles, this study examines counter-terror statutes and determines whether Locke would support them
Omega-3 Fatty Acids Mitigating Isotretinoin-Induced Cheilitis
Get PDFWhilst isotretinoin is an effective treatment for severe acne vulgaris, isotretinoin induced cheilitis is one of the most troubling side effects of the treatment. In their excellent review, which briefly covers the treatments for isotretinoin induced cheilitis, Narayaran et al have overlooked the utility of Omega-3 Fatty Acids (O3FA). O3FA, a cluster of long-chain and very-long-chain polyunsaturated fatty acids that the human body cannot synthesise intrinsically, have demonstrated efficacy in improving specific conditions characterised by inflammation, dryness, and moisture loss
Evaluating the Effectiveness of the Peer Data Labelling System (PDLS)
No full textThe Peer Data Labelling System (PDLS) is a novel and extensible approach to generating labelled data suitable for training supervised machine learning (ML) algorithms for use in Child Computer Interaction (CCI) research and development. For a supervised ML model to make accurate predictions it requires accurate data on which to train. Poor quality input data to systems results in poor quality outputs often referred to as garbage in, garbage out (GIGO) systems.
PDLS is an alternative system to commonly employed approaches to facial and emotion recognition such as the Facial Action Coding System (FACS) or algorithmic approaches such as AFFDEX or FACET.
This paper presents the approaches taken to evaluate the effectiveness of PDLS. Algorithmic approaches did not produce consistent classifications and major amendments to the PDLS would be required if that validation route was pursued. The human review process found that the pupil observers and reviewers reached consensus in classifying most of the data as engaged. Recognising disengagement is more challenging, and further work is required to ensure that there is more consistency in what the participants recognise as engagement and disengagement
Stimulation of hair regrowth in an animal model of androgenic alopecia using 2-deoxy-D-ribose
Get PDFAndrogenic alopecia (AGA) affects both men and women worldwide. New blood vessel formation can restore blood supply and stimulate the hair regrowth cycle. Recently, our group reported that 2-deoxy-D-ribose (2dDR) is 80%–90% as effective as VEGF in the stimulation of neovascularization in in vitro models and in a chick bioassay. In this study, we aimed to assess the effect of 2dDR on hair growth. We prepared an alginate gel containing 2dDR, polypropylene glycol, and phenoxyethanol. AGA was developed in C57BL6 mice by intraperitoneally injecting testosterone (TE). A dihydrotestosterone (DHT)-treated group was used as a negative control, a minoxidil group was used as a positive control, and we included groups treated with 2dDR gel and a combination of 2dDR and minoxidil. Each treatment was applied for 20 days. Both groups treated with 2dDR gel and minoxidil stimulated the morphogenesis of hair follicles. H&E-stained skin sections of C57BL/6 mice demonstrated an increase in length, diameter, hair follicle density, anagen/telogen ratio, diameter of hair follicles, area of the hair bulb covered in melanin, and an increase in the number of blood vessels. Masson’s trichrome staining showed an increase in the area of the hair bulb covered in melanin. The effects of the FDA-approved drug (minoxidil) on hair growth were similar to those of 2dDR (80%–90%). No significant benefit were observed by applying a combination of minoxidil with 2dDR. We conclude that 2dDR gel has potential for the treatment of androgenic alopecia and possibly other alopecia conditions where stimulation of hair regrowth is desirable, such as after chemotherapy. The mechanism of activity of 2dDR remains to be established
Food fortification programmes and zinc deficiency
Get PDFThe complex realities of most countries grappling with zinc deficiency pose challenges to the implementation of highly compliant, mandatory, large-scale food fortification programmes