Design of experiments to study the impact of process parameters on droplet size and development of non-invasive imaging techniques in tablet coating

Atomisation of an aqueous solution for tablet film coating is a complex process with multiple factors determining droplet formation and properties. The importance of droplet size for an efficient process and a high quality final product has been noted in the literature, with smaller droplets reported to produce smoother, more homogenous coatings whilst simultaneously avoiding the risk of damage through over-wetting of the tablet core. In this work the effect of droplet size on tablet film coat characteristics was investigated using X-ray microcomputed tomography (XμCT) and confocal laser scanning microscopy (CLSM). A quality by design approach utilising design of experiments (DOE) was used to optimise the conditions necessary for production of droplets at a small (20 μm) and large (70 μm) droplet size. Droplet size distribution was measured using real-time laser diffraction and the volume median diameter taken as a response. DOE yielded information on the relationship three critical process parameters: pump rate, atomisation pressure and coating-polymer concentration, had upon droplet size. The model generated was robust, scoring highly for model fit (R2 = 0.977), predictability (Q2 = 0.837), validity and reproducibility. Modelling confirmed that all parameters had either a linear or quadratic effect on droplet size and revealed an interaction between pump rate and atomisation pressure. Fluidised bed coating of tablet cores was performed with either small or large droplets followed by CLSM and XμCT imaging. Addition of commonly used contrast materials to the coating solution improved visualisation of the coating by XμCT, showing the coat as a discrete section of the overall tablet. Imaging provided qualitative and quantitative evidence revealing that smaller droplets formed thinner, more uniform and less porous film coats

Selected Letters of Ananda K. Coomaraswamy

Terlepas dari pengaruh unik A. K. Coomaraswamy di timur dan barat, sedikit yang diketahui tentang orang di balik tulisan tersebut. Coomaraswamy membenci tulisan otobiografi dan menganggapnya vulgar yang melayani keingintahuan yang tidak sah. Namun pria ini menulis ribuan surat, di setiap surat menjalin kontak pribadi yang intim dengan koresponden. Kata demi kata, kalimat demi kalimat, dengan ketelitian yang sangat tajam, dia mengikuti proses berpikir orang lain. Seperti yang dikatakan Eric Gill tentang dia: 'Kamu memukul lurus dan berdarah keras dan sering berdarah'.Surat-surat yang termasuk dalam jilid ini, yang diterbitkan untuk pertama kalinya, mengungkapkan keberadaan pria tanpa kompromi ini yang tidak percaya pada teori atau ideologi, politik atau filsafat. Dengan ketelitian ilmiah yang diperoleh melalui pelatihannya sebagai seorang ahli geologi, dikombinasikan dengan kepekaannya yang luar biasa, dia mengarahkan dirinya pada disiplin ilmu sejarah, filsafat, agama, seni dan kerajinan. Surat-surat itu ditulis kepada orang-orang sezaman, ilmuwan, Sansekerta, biksu dan penyair Buddha, dan termasuk orang-orang seperti Schweitzer, Eric Gill, Northov, Herman Goetz, Muirhead, Needham, George Sarton, dan banyak lainnya. Mereka mengungkapkan jangkauan pikiran yang luar biasa yang melintasi peradaban, budaya, bahasa, seni dan kerajinan, yang mencakup keseluruhan

The ethical ambivalence of resistant violence: notes from postcolonial south Asia

In the face of mounting militarism in south Asia, this essay turns to anti-state, ‘liberatory’ movements in the region that employ violence to achieve their political aims. It explores some of the ethical quandaries that arise from the embrace of such violence, particularly for feminists for whom political violence and militarism is today a moot point. Feminist responses towards resistant political violence have, however, been less straightforward than towards the violence of the state, suggesting a more ambivalent ethical position towards the former than the latter. The nature of this ambivalence can be located in a postcolonial feminist ethics that is conceptually committed to the use of political violence in certain, albeit exceptional circumstances on the basis of the ethical ends that this violence (as opposed to other oppressive violence) serves. In opening up this ethical ambivalence – or the ethics of ambiguity, as Simone de Beauvoir says – to interrogation and reflection, I underscore the difficulties involved in ethically discriminating between forms of violence, especially when we consider the manner in which such distinctions rely on and reproduce gendered modes of power. This raises particular problems for current feminist appraisals of resistant political violence as an expression of women's empowerment and ‘agency’