Studies in isothiazole chemistry: I. isothiazolo [5,4-b] pyridines. II. approaches to isothiazolynes

The first part of this thesis describes investigations on the synthesis and chemistry of isothiazolo[5,4-b] pyridines. The syntheses of a number of alkyl isothiazolo[5,4-b] pyridines from 5-amino-3-methylisothiazole under conditions of the Skraup reaction are described and their nuclear magnetic resonance spectra are discussed. The reactions of 3-methyl- and 3,6-dimethylisothiazolo[5,4-b] pyridine have been studied. In particular they did not undergo nitration under the conditions employed and whereas the 3-methyl compound did not condense with benzaldehyde, 3,6-dimethylisothiazolo[5,4-b] pyridine gave mono-styryl products with benzaldehyde, and p-nitrobenzaldehyde. Potassium permanganate oxidation gave isothiazolo[5,4-b] pyrid-3(2H)-one 1,1-dioxides rather than the expected isothiazolo[5,4-b] pyridine carboxylic acids and chromic acid oxidation resulted in cleavage of the isothiazole ring to give 2,3-disubstituted pyridines. Ethyl 4-hydroxy-3-methylisothiazolo[5,4-b] pyridine-5-earboxylabe was readily obtained by thermal cyclisation of the malonate from 5-amino-3-methylisothiazole and ethoxymethylenemalonic ester. The hydroxyl ester was converted to a number of substituted isothiazolo[5,4-b] pyridines. In addition it has been established that methylation at nitrogen rather than oxygen occurs with both the 4-hydroxy ester and the 4-hydroxy compound which has been shown to exist preferentially in the carbonyl form, namely 3-methylisothiazolo[5,4-b] _7pyrid-4-one. The reaction of 5-amino-3-methylisothiazole with ethylacetoacetate and with acetylacetone under the conditions of the Conrad Limpach reaction and the Combes reaction respectively, did not give isothiazolo[5,4-b] pyridines. The latter gave a product which has been tentatively formulated as 5-acetyl-3,4-dimethylisothiazole. The second part of this work describes the synthesis of 5-amino-3-chloroisothiazole-4-carboxylic acid, 4-amino-3-methylisothiazole- 5-carboxylic acid and 4-aminoisothiazole-3-carboxylic acid and experiments aimed at investigating the possible intermediacy of isothiazolynes. Attempts to generate and trap isothiazolynes by their aprotic diazotisation with isoainyl nitrite in the presence of 2,3,4,5-tetraphenylcyclopentadienone gave only small quantities of isothiazoles in addition to a variety of oxidation products derived from the arynophile. 4-Amino3-methylisothiazole-5-carboxylic acid gave isothiazolyl-substituted products when furan and anthracene were used as trapping agents, and it was found that the reaction of isothiazole-4-diazonium carboxylate hydrochloride and propylene oxide in the presence of furan gave 4,-cyano-1,2,3-thiadiazole. In none of the reactions investigated was there any evidence for the formation of inothiazolyne intermediates

Making gazes explicit: facilitating epistemic access in the humanities

The final publication of this article is available at Springer via http://dx.doi.org/10.1007/s10734-013-9651-7.This paper addresses the problem of curriculum design in the Humanities and Social Sciences, and more specifically the challenge of designing foundation courses for first-generation or 'disadvantaged' learners. Located in the social realist school of the sociology of education studies that builds on the legacy of Basil Bernstein, we emphasise the importance of knowledge and understanding the principles that generate 'what counts' in particular courses and disciplines. In order to operationalise this, we used Maton's Legitimation Code Theory to uncover the knowledge/knower structures in eight first year courses in four of the most popular majors in a Faculty of Humanities. Our data sources were curriculum documents and exam papers in particular. The findings are presented and the 'codes', 'gazes, and 'lenses' for each set of courses delineated. The findings are being used to inform the design of a set of curriculum and pedagogic interventions that aim to offer powerful ways of knowing to novices in the Humanities and Social Sciences

The social uses of the online chatroom as a boundary object for the acquisition of academic literacy in pandemic times

The Covid-19 pandemic has been a catalyst for ongoing pedagogic changes in the higher education landscape, especially with the use of online modes of delivery. The digital shift triggered questions around student engagement and the need to ensure that, despite physical distancing, students did not feel alienated from online learning spaces. This was part and parcel of our ethics of care prerogative. In the context of teaching academic literacy online, our teaching experiences have prompted us to interrogate how we understand student participation and sense-making in online spaces during the pandemic. This is particularly important for us, as we view academic literacy as a set of socially embedded practices rather than decontextualised skills (Street, 1983). We argue that during the Covid-19 pandemic, the online chatroom as a boundary object (Bowker & Star, 2000) was recruited as a proxy for the traditional classroom. We focus on how this boundary object was recruited by us as academic literacy lecturers in our first-year academic literacy course to realise certain features of our pedagogy of discomfort. Through a critical discourse analysis of written interactions in the chatroom, we explore how we as lecturers constrained the multiple social uses of the chatroom in order to imbue it with a particular function, a sense-making space for the acquisition of academic literacy in the context of ‘Emergency Remote Teaching’

Locating academic development within the decolonial turn in higher education: The affordances of systems thinking for decolonial practice

The student protests of 2015 and 2016 (re)surfaced the call to decolonise South African higher education (HE), highlighting the alienation experienced by black students within historically white institutions. This article describes how an academic development unit at one such institution responds as part of its reconceptualisation process. We consider the interplay between policy, structure, and practice within our context, and the extent to which these enable decolonial work. We also show how approaches to decolonisation within HE work to reinscribe coloniality and argue that these must be holistic and intentional to transform exclusionary institutional practices and the structures that sustain them.  Drawing on the area of support services, which is typically designed around individualistic approaches to help-seeking, we illustrate, through a case study, how systems thinking principles enable productive decolonial work within colonial structures, and their affordances to inform policy for an integrated and responsive student support system

The Messiness of Meaning Making: Examining the Affordances of the Digital Space as a Mentoring and Tutoring Space for the Acquisition of Academic Literacy

Having incorporated a digital aspect to our academic literacy course, and having monitored this over the last three years, we have come to believe that online mentoring can serve as an essential form of tutoring and mentoring. Our study is located in the field of New Literacy Studies and examines the affordancesof a digital space in a first year academic literacy course in the Humanities. We focus on students’ acquisition of academic literacy, as well as critical thinking and reflexivity around a core social science concept; identity. Here, we refer to the ability to think critically and reflexively, as the ‘analytical mode’,a key driver in shaping the pedagogy of the course. In this paper, we explore the online participation of two students and how they engage with the theme of identity, not only as an academic concept but also as one intrinsically linked with how they see themselves in a diverse post-apartheid SouthAfrican context. We argue that the digital space promotes a particular form of the ‘analytical mode’ as students grapple with texts and concepts on the academic literacy course. Using a qualitative case study methodology, our analysis of students’ online interaction revealed that the digital space allowed students to express themselves with a level of depth and sophistication, and to share dissident views that could not be expressed in the traditional classroom space. Furthermore, we argue that the digital space can suspend students’ urgency to agree or disagree with the arguments of authors they read. By holdingstudents between the two positions of agreement and disagreement, we propose that the digital space becomes a space of reflexive1 discomfort which captures various moments in students’ drafting processes as they operate within the analytical mode. Therefore, we argue that the digital space, if harnessed with a particular type of mentoring philosophy and pedagogy that activates the analytical mode, can free up the traditional forms of academic mentoring and tutoring within the academy. This allows students the freedom to live with the messiness of their texts and to grapple with their conceptual understanding, and in doing so, develop their ‘authorial self’ (Clark & Ivanič, 1997)

The Messiness of Meaning Making: Examining the Affordances of the Digital Space as a Mentoring and Tutoring Space for the Acquisition of Academic Literacy

Having incorporated a digital aspect to our academic literacy course, and having monitored this over the last three years, we have come to believe that online mentoring can serve as an essential form of tutoring and mentoring. Our study is located in the field of New Literacy Studies and examines the affordances of a digital space in a first year academic literacy course in the Humanities. We focus on students’ acquisition of academic literacy, as well as critical thinking and reflexivity around a core social science concept; identity. Here, we refer to the ability to think critically and reflexively, as the ‘analytical mode’, a key driver in shaping the pedagogy of the course. In this paper, we explore the online participation of two students and how they engage with the theme of identity, not only as an academic concept but also as one intrinsically linked with how they see themselves in a diverse post-apartheid South African context. We argue that the digital space promotes a particular form of the ‘analytical mode’ as students grapple with texts and concepts on the academic literacy course. Using a qualitative case study methodology, our analysis of students’ online interaction revealed that the digital space allowed students to express themselves with a level of depth and sophistication, and to share dissident views that could not be expressed in the traditional classroom space. Furthermore, we argue that the digital space can suspend students’ urgency to agree or disagree with the arguments of authors they read. By holding students between the two positions of agreement and disagreement, we propose that the digital space becomes a space of reflexive1 discomfort which captures various moments in students’ drafting processes as they operate within the analytical mode. Therefore, we argue that the digital space, if harnessed with a particular type of mentoring philosophy and pedagogy that activates the analytical mode, can free up. the traditional forms of academic mentoring and tutoring within the academy. This allows students the freedom to live with the messiness of their texts and to grapple with their conceptual understanding, and in doing so, develop their ‘authorial self’ (Clark & Ivanič, 1997)

Don’t throw the colonial text out with its ideology!: Recruiting a colonial text to do decolonial work on a university academic literacy course

Since 2015, South African universities have undergone a major overhaul, with students nationwide calling for curriculum reform to introduce texts and approaches that do not perpetuate colonial ideologies. This presented an opportunity to shed untransformed ways of knowing, and recent publications in the region reflect this impetus. It is in this climate, in 2019, that our course, Writing Across Borders, was launched to foster critical literacy practices, exposing students to diverse texts, including a history textbook published in 1909. Our use of this textbook presently could be questioned. We argue, however, that instead of throwing the colonial text out with its ideology, it can be recruited differently to reveal its problematic constructions of race and contradictions. This article models the class discussions around the history textbook, applying a critical discourse analysis lens, which allows for multi-layered analysis, and surfaces asymmetries of power that created the conditions for social injustices in colonial and postcolonial contexts. The analysis demonstrates that meaning does not reside in the text alone, but in how it is used to achieve its decolonial meaning potential, and to invite us all to unlearn our enduring racial biases. It thus offers us pedagogical possibilities by harnessing colonial texts differently

Body composition-derived BMI cut-offs for overweight and obesity in Indians and Creoles of Mauritius: comparison with Caucasians

Global estimates of overweight and obesity prevalence are based on the World Health Organisation (WHO) body mass index (BMI) cut-off values of 25 and 30 kg m⁻², respectively. To validate these BMI cut-offs for adiposity in the island population of Mauritius, we assessed the relationship between BMI and measured body fat mass in this population according to gender and ethnicity.Methods: In 175 young adult Mauritians (age 20-42 years) belonging to the two main ethnic groups—Indians (South Asian descent) and Creoles (African/Malagasy descent), body weight, height and waist circumference (WC) were measured, total body fat assessed by deuterium oxide (D2O) dilution and trunk (abdominal) fat by segmental bioimpedance analysis.Results: Compared to body fat% predicted from BMI using Caucasian-based equations, body fat% assessed by D2O dilution in Mauritians was higher by 3–5 units in Indian men and women as well as in Creole women, but not in Creole men. This gender-specific ethnic difference in body composition between Indians and Creoles is reflected in their BMI–Fat% relationships, as well as in their WC–Trunk Fat% relationships. Overall, WHO BMI cut-offs of 25 and 30 kg m⁻² for overweight and obesity, respectively, seem valid only for Creole men (~24 and 29.5, respectively), but not for Creole women whose BMI cut-offs are 2–4 units lower (21–22 for overweight; 27–28 for obese) nor for Indian men and women whose BMI cut-offs are 3–4 units lower (21–22 for overweight; 26–27 for obese).Conclusions: The use of BMI cut-off points for classifying overweight and obesity need to take into account both ethnicity and gender to avoid gross adiposity status misclassification in this population known to be at high risk for type-2 diabetes and cardiovascular diseases. This is particularly of importance in obesity prevention strategies both in clinical medicine and public health