Solution calorimetry as a tool for investigating drug interaction with intestinal fluid

Solution calorimetry offers a reproducible technique for measuring the enthalpy of solution (ΔsolH) of a solute dissolving into a solvent. The ΔsolH of two solutes, propranolol HCl and mannitol were determined in simulated intestinal fluid (SIF) solutions designed to model the fed and fasted states within the gut, and in Hanks’ balanced salt solution (HBSS) of varying pH. The bile salt and lipid within the SIF solutions formed mixed micelles. Both solutes exhibited endothermic reactions in all solvents. The ΔsolH for propranolol HCl in the SIF solutions differed from those in the HBSS and was lower in the fed state than the fasted state SIF solution, revealing an interaction between propranolol and the micellar phase in both SIF solutions. In contrast, for mannitol the ΔsolH was constant in all solutions indicating minimal interaction between mannitol and the micellar phases of the SIF solutions. In this study, solution calorimetry proved to be a simple method for measuring the enthalpy associated with the dissolution of model drugs in complex biological media such as SIF solutions. In addition, the derived power–time curves allowed the time taken for the powdered solutes to form solutions to be estimated.

Strategies for combating gendered perceptions of careers

Purpose – Earlier work on career choice has identified that career choice involves gendered processes which lead to differentiated career outcomes for women and men. However, this literature remained anaemic in offering career counselling strategies for addressing the negative impacts of these processes. The paper aims to explore the creativity cycle and other tools derived from personal construct psychology (PCP) and other feminist literature as potential means for dissolving gendered perceptions of various professions and organisational practices. Design/methodology/approach – This is a conceptual paper. Findings – The paper argues that PCP can provide a theoretical and methodological framework for discussing how dichotomous and gender identified the perceptions of professions can be and how such perceptions might be challenged. Practical implications – This theory and its techniques allow us an exploration of the flexibility of one’s constructions system, which determines a person’s ability to construe alternative views and to develop new ways of understanding oneself and others. Originality/value – The PCP’s potential as a technique to combat gendered perceptions of a career is examined.

A NEW METHOD TO OBTAIN GOOD ANATOMICAL SLIDES OF HETEROGENEOUS PLANT PARTS

A new method is presented to prepare anatomical slides of plant materials including a combination of soft and hard tissues, such as stems with cambial variants, arboreal monocotyledons, and tree bark The method integrates previous techniques aimed at softening the samples and making them thereby more homogeneous, with the use of anti-tearing polystyrene foam solution In addition, we suggest two other alternatives to protect the sections from tearing adhesive tape and/or Mayer`s albumin adhesive, both combined with the polystyrene foam solution This solution is cheap and easy to make by dissolving any packaging polystyrene m butyl acetate It is applied before each section is cut on a sliding microtome and ensures that all the tissues in the section will hold together This novel microtechnical procedure will facilitate the study of heterogeneous plant portions, as shown in some illustrated examples

The direct determination of rare earth elements in basaltic and related rocks using ICP-MS: Testing the efficiency of microwave oven sample decomposition procedures

Tests are described showing the results obtained for the determination of REE and the trace elements Rb, Y, Zr, Nb, Cs, Ba, Hf, Ta, Pb, Th and U with ICP-MS methodology for nine basaltic reference materials, and thirteen basalts and amphibolites from the mafic-ultramafic Niquelandia Complex, central Brazil. Sample decomposition for the reference materials was performed by microwave oven digestion (HF and HNO(3), 100 mg of sample), and that for the Niquelandia samples also by Parr bomb treatment (5 days at 200 degrees C, 40 mg of sample). Results for the reference materials were similar to published values, thus showing that the microwave technique can be used with confidence for basaltic rocks. No fluoride precipitates were observed in the microwave-digested solutions. Total recovery of elements, including Zr and Hf, was obtained for the Niquelandia samples, with the exception of an amphibolite. For this latter sample, the Parr method achieved a total digestion, but not so the microwave decomposition; losses, however, were observed only for Zr and Hf, indicating difficulty in dissolving Zr-bearing minerals by microwave acid attack.

Synthesis and Characterization of Magnetic Composites Based on Cis-Polyisoprene and CoFe(2)O(4) Nanoparticles

CoFe(2)O(4) nanoparticles were obtained by the co-precipitation method. They were further modified by the adsorption of ricinoleic acid (RA). The non-modified and modified CoFe(2)O(4)/RA nanoparticles were characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), Raman, and Fourier transform infrared (FTIR) spectroscopy. The modified particles present a mean diameter < 20 nm. The adsorption of RA on the CoFe(2)O(4) surface is characterized by the IR absorptions of the RA while in the Raman spectrum the predominant signals are those from the CoFe(2)O(4). The cis-polyisoprene (PI) composite was prepared by dissolving PI in cyclohexane followed by the addition of a magnetic fluid based on CoFe(2)O(4)/RA nanoparticles dispersed in cyclohexane. After solvent evaporation a magnetic composite was obtained and characterized by AFM, Raman, and FTIR measurements. AFM images show uniformly CoFe(2)O(4)/RA particles distributed in the PI matrix. Raman spectra obtained for the composites reveal the characteristic Raman peaks of PI and CoFe(2)O(4) nanoparticles.

Valorization of an Industrial Organosolv-Sugarcane Bagasse Lignin: Characterization and Use as a Matrix in Biobased Composites Reinforced With Sisal Fibers

In the present study, the main focus was the characterization and application of the by-product lignin isolated through an industrial organosolv acid hydrolysis process from sugarcane bagasse, aiming at the production of bioethanol. The sugarcane lignin was characterized and used to prepare phenolic-type resins. The analysis confirmed that the industrial sugarcane lignin is of HGS type, with a high proportion of the less substituted aromatic ring p-hydroxyphenyl units, which favors further reaction with formaldehyde. The lignin-formaldehyde resins were used to produce biobased composites reinforced with different proportions of randomly distributed sisal fibers. The presence of lignin moieties in both the fiber and matrix increases their mutual affinity, as confirmed by SEM images, which showed good adhesion at the biocomposite fiber/matrix interface. This in turn allowed good load transference from the matrix to the fiber, leading to biobased composites with good impact strength (near 500 J m(-1) for a 40 wt% sisal fiber-reinforced composite). The study demonstrates that sugarcane bagasse lignin obtained from a bioethanol plant can be used without excessive purification in the preparation of lignocellulosic fiber-reinforced biobased composites displaying high mechanical properties. Biotechnol. Bioeng. 2010;107: 612-621. (C) 2010 Wiley Periodicals, Inc.

Chitosan, sisal cellulose, and biocomposite chitosan/sisal cellulose films prepared from thiourea/NaOH aqueous solution

Environmentally friendly biocomposites were successfully prepared by dissolving chitosan and cellulose in a NaOH/thiourea solvent with subsequent heating and film casting. Under the considered conditions, NaOH/thiourea led to chain depolymerization of both biopolymers without a dramatic loss of film forming capacities. Compatibility of both biopolymers in the biocomposite was firstly assessed through scanning electron microscopy, revealing an intermediate organization between cellulose fiber network and smoothness of pure chitosan. DSC analyses led to exothermic peaks close to 285 and 315 degrees C for the biocomposite, compared to the exothermic peaks of chitosan (275 degrees C) and cellulose (265 and 305 degrees C), suggesting interactions between chitosan and cellulose. Contact angle analyses pointed out the deformation that can occur at the surface due to the high affinity of the;e materials with water. T(2) NMR relaxometry behavior of biocomposites appeared to be dominated by chitosan. Other properties of films, as crystallinity, water sorption isotherms, among others, are also discussed. (C) 2010 Published by Elsevier Ltd.

The Philosophy of Dissonant Children : Stanley Cavell's Wittgensteinian Philosophical Therapies as an Educational Conversation

Education is often understood as a process whereby children come to conform to the norms teachers believe should govern our practices. This picture problematically presumes that educators know in advance what it means for children to go on the way that is expected of them. In this essay Viktor Johansson suggests a revision of education, through the philosophy of Stanley Cavell, that can account for both the attunement in our practices and the possible dissonance that follows when the teacher and child do not go on together. There is an anxiety generated by the threat of disharmony in our educational undertakings that may drive teachers toward philosophy in educational contexts. Here Johansson offers a philosophical treatment of this intellectual anxiety that teachers may experience when they, upon meeting dissonant children, search for epistemic justifications of their practices—a treatment whereby dissonant children can support teachers in dissolving their intellectual frustrations.

Självet, rollerna och pågående koordinationer av mänskliga handlingar : Om att försöka se ’samhället’ som något annat än fängelse eller marionetteater

The self, roles and the ongoing coordination of human action. Trying to see ‘society’ as neither prison nor puppet theatre In the article it is argued that structural North-American role-sociology may be integrated with theories emphasizing ‘society’ as ongoing processes (f. ex. Giddens’ theory of structuration). This is possible if the concept of role is defined as a recurrence oriented to the action of others standing out as a regularity in a societal process. But this definition makes it necessary to in a fundamental way understand what kind of social being the role-actor is. This is done with the help of Hans Joas’ theory of creativity and Merleau-Pontys concept of ‘flesh’ arguing that Meads concept of the ‘I’ maybe understood as an embodied self-asserting I, which at least in reflexive modernity has the creative power to split Meads ‘me’ into a self-voiced subject-me and an other voiced object-me. The embodied I communicating with the subject-me may be viewed as that role-actor which is something else than the role played. But this kind of role-actor is making for new troubles because it is hard to understand how this kind of self is creating self-coherence by using Meads concept of ‘the generalized other’. This trouble is handled by using Alain Touraines concept of the ‘subject’ and arguing that the generalized other is dissolving in de-modernized modernity. In split modernity self-coherence may instead be created by what in the article is called the generalized subject. This concept means a kind of communicative future based evaluation, which has its base in the ‘subject’ opposing the split powers of both the instrumentality of markets and of life-worlds trying to create ‘fundamentalistic’ self-identities. This kind of self is communicative because it also must respect the other as ‘subject’. It exists only in the battle against the forces of the market or a community. It never constructs an ideal city or a higher type of individual. It creates and protects a clearing that is constantly being invaded, to use the words of the old Frenchman himself. Asa kind of test-case it is by the way in the article shown how Becks concept of individualization may be understood in a deeply social and role-sociological way.

A rapid test for heroin (3,6-Diacetylmorphine) based on two chemiluminescence reactions

A rapid method for screening drug seizure samples for 3,6-diacetylmorphine (heroin), which consists of a simple hydrolysis procedure and flow-injection analysis with two chemiluminescence reagents, is described. Before hydrolysis, 3,6-diacetylmorphine evokes an intense response with a tris(2,2'-bipyridyl)ruthenium(III) reagent (prepared by dissolving the perchlorate salt in acetonitrile), and a relatively weak chemiluminescence response with a second reagent: potassium permanganate in an aqueous acidic polyphosphate solution. However, the permanganate reagent is extremely sensitive toward the hydrolysis products of 3,6-diacetylmorphine (i.e., 6-monoacetylmorphine and morphine). Some compounds commonly found in drug laboratories may cause false positives with tris(2,2'-bipyridyl)ruthenium(III), but do not produce the markedly increased response with the permanganate reagent after the hydrolysis procedure. The combination of these two tests therefore provides an effective presumptive test for the presence of 3,6-diacetylmorphine, which we have verified with 14 samples obtained from a forensic science laboratory.

Within and against performativity : discursive engagement in adult literacy and basic education

The field of adult literacy and basic education (ALBE) has undergone dramatic changes in recent years with the advent of labour market programs, accreditation, competency-based assessment and competitive tendering for program funds. Teachers' working conditions have deteriorated and their professional autonomy has been eroded. ALBE has been increasingly instrumentalised to fulfil the requirements of a marketised economy and conform to its norms. The beliefs and value systems which traditionally underpinned the work of ALBE teachers have been reframed according to the principle of 'performativity' and the demands of the 'performative State' (Lyotard, 1984: 46, Yeatman 1994: 110). The destabilisation of teachers' working lives can be understood as a manifestation of the 'postmodern condition' (Lyotard 1984; Harvey 1989): the collapse of the certainties and purposes of the past; the proliferation of technologies; the impermanence and intensification of work; the commodification of knowledge and curricula; and the dissolving of boundaries between disciplines and fields of knowledge. The critiques of the modernist grand narratives which underpin progressivist and critical approaches to adult literacy pedagogy have further undermined the traditional points of reference of ALBE teachers. In this thesis I examine how teachers are teaching, surviving, resisting, and 'living the contradictions' (Seddon 1994) in the context of struggles to comply with and resist the requirements of performativity. Following Foucault and a number of feminist poststructuralist authors, I have applied the notions of 'discursive engagement' and 'the politics of discourse' (Yeatman 1990a) as a way of theorising the interplay between imposed change and teachers' practice. I explore the discursive practices which take place at the interface between the 'new' policy discourses and older, naturalised discourses; how teachers are engaged by and are engaging with discourses of performativity; how teachers are discursively constructing adult literacy pedagogy; what new, hybrid discourses of 'good practice' are emerging; and the micropractices of resistance which teachers are enacting in their speech and in their practice. My purpose was to develop knowledge which would support the reflexivity of teachers; to enrich the theoretical languages that teachers could draw upon in trying to make sense of their situation; and to use those languages in speaking about the dilemmas of practice. I used participatory action research as a means of producing knowledge about teachers' practices, structured around their agency, and reflecting their standpoint (Harding 1993). I describe two separate action research projects in which teachers of ALBE participated. I reflect on both projects in the light of poststructuralist theory and consider them as instances of what Lather calls 'within/against research' (Lather 1989: 27). I analyse written and spoken texts produced in both projects which reflect teachers' responses to competency-based assessment and other features of the changing context. I use a method of discourse mapping to describe the discursive field and the teachers' discursive practices. Three main configurations of discourse are delineated: 'progressivism', 'professional teacher' and 'performativity'. The teachers mainly position themselves within a hybridising 'progressivist /professional teacher' discourse, as a discourse of resistance to 'performative' discourse. In adapting their pedagogies, the teachers are in some degree taking the language and world view of performativity into their own vocabularies and practices. The discursive picture I have mapped is complex and contradictory. On one hand, the 'progressivist /professional teacher' discourse appears to endure and to take strength from the articulation into it of elements of performative discourse, creating new possibilities for discursive transformation. On the other hand, there are signs that performative discourse is colonising and subsuming progressivist /professional teacher discourse. At times, both of these tendencies are apparent in the one text. Six micropractices of resistance are identified within the texts: 'rational critique', 'objectification', 'subversion', 'refusal', 'humour' and 'the affirmation of desire'. These reflect the teachers' agency in making discursive choices on the micro level of their every day practices. Through those micropractices, the teachers are engaging with and resisting the micropractices and meanings of performativity. I apply the same multi-layered method of analysis to an examination of discursive engagement in pedagogy by analysing a transcript of the teachers' discussion of critical incidents in their classrooms. Their classroom pedagogies are revealed as complex, situated and eclectic. They are combining and integrating their 'embodied' and their 'institutional' powers, both 'seducing' (McWilliam 1995) and 'regulating' (Gore 1993) as they teach. A strong ethical project is apparent in the teachers' sense of social responsibility, in their determination to adhere to valued traditions of previous times, and in their critical self-awareness of the ways in which they use their institutional and embodied powers in the classroom. Finally, l look back on the findings, and reflect on the possibilities of discursive engagement and the politics of discourse as a framework for more strategic practice in the current context. This research provides grounds for hope that, by becoming more self-conscious about how we engage discursively, we might become more strategic in our everyday professional practice. Not withstanding the constraints (evident in this study) which limit the strategic potential of the politics of discourse, there is space for teachers to become more reflexive in their professional, pedagogical and political praxis. Development of more deliberate, self-reflexive praxis might lead to a 'postmodern democratic polities' (Yeatman 1994: 112) which would challenge the performative state and the system of globalised capital which it serves. Short abstract Adult literacy and basic education (ALBE) teachers have experienced a period of dramatic policy change in recent years; in particular, the introduction of competency-based assessment and competitive tendering for program funds. 'Discourse politics' provides a way of theorising the interplay between policy-mediated institutional change and teachers' practice. The focus of this study is 'discursive engagement'; how teachers are engaged by and are engaging with discourses of performativity. Through two action research projects, texts were generated of teachers talking and writing about how they were responding to the challenges, and developing their pedagogies in the new policy environment. These texts have been analysed and several patterns of discursive engagement delineated, named and illustrated. The strategic potential of 'discourse polities' is explored in the light of the findings.

An analysis of microband orientation in hot deformed aluminium alloy AA5052 using forward and reverse torsion

The effects of strain path reversal on the macroscopic orientation of microbands in AA5052 have been studied using high resolution electron backscatter diffraction. Deformation was carried using two equal steps of forward/forward or forward/reverse torsion at a temperature of 300°C and strain rate of 1s-1 to a total equivalent tensile strain of 0.5. In both cases microbands were found in the majority of grains examined with many having more than one set. The microbands appear to cluster at specific angles to the macroscopic deformation. For the forward/forward condition microbands clustered around -20° and +45° to the maximum principle stress direction and at ± 30-35° to the principal strain direction. For the forward/reverse condition significantly more spread in microband angle was observed though peaks were visible at ±35° with respect to principal stress direction and at -40° and +30° with respect to the principal strain direction of the reverse torsion. This suggests the microbands formed in the forward deformation have or are dissolving and any new microbands formed are related to the deformation conditions of the final strain path.

Localized relaxational dynamics of succinonitrile

Succinonitrile (N≡C—CH₂—CH₂—C≡N) is a good ionic conductor, when doped with an ionic compound, at room temperature, where it is in its plastic crystalline phase (Long et al. Solid State Ionics 2003, 161, 105; Alarco et al. Nat. Mater. 2004, 3, 476). We report on the relaxational dynamics of the plastic phase near the two first-order phase transitions and on the effect of dissolving a salt in the plastic matrix by quasi-elastic neutron scattering. At 240 K, the three observed relaxations are localized and we can describe their dynamics (τ ≈ 1.7, 17, and 140 ps) to a certain extent from a model using a single molecule that was proposed by B_ée et al. allowing for all conformations in its unit cell (space group IM3M). The extent of the localized motion as observed is however larger than that predicted by the model and suggests that the isomerization of succinonitrile is correlated with a jump to the nearest neighbor site in the unit cell. The salt containing system is known to be a good ionic conductor, and our results show that the effect of the ions on the succinonitrile matrix is homogeneous. Because the isomerizations and rotations are governed by intermolecular interactions, the dissolved ions have an effect over an extended range. Due to the addition of the salt, the dynamics of one of the components (τ ≈ 17 ps) shows more diffusive character at 300 K. The calculated upper limit of the corresponding diffusion constant of succinonitrile in the electrolyte is a factor 30 higher than what is reported for the ions. Our results suggest that the succinonitrile diffusion is caused by nearest neighbor jumps that are localized on the observed length and time scales.

Mana Taonga and the public sphere: a dialogue between indigenous practice and Western theory

Recent re-conceptualizations of the ‘public sphere’ facilitated a much needed shift in thinking about identity politics ‘from a substance … to a movement’ (Weibel and Latour, 2007). This laid the foundation for dissolving the ‘emanatist vision’ (Bourdieu, 1990) of self-explanatory and perpetual systems and structures towards the interrogation of actions and performances that simultaneously constitute and are affected by such wider socio-political realities. Most academic contributions, however, remain on a normative or theoretical level without offering empirical insights.

This article introduces Mana Taonga as an Indigenous Māori concept of cultural politics embedded in current museum practice at the Museum of New Zealand Te Papa Tongarewa (Te Papa). It creates a dialogue between Indigenous Māori practice and Western theory leading to a refined understanding of performative democracy within a museum as forum, or public sphere. The authors argue that a specific museum offers a particular place, space and empirical reality to interrogate seemingly universal concepts such as ‘culture’ and ‘politics’ by blending theoretical notions with an awareness of institutional contexts and practices.