Lipid productivity and cell wall ultrastructure of six strains of Nannochloropsis: Implications for biofuel production and downstream processing

Microalgae are generating considerable interest for third generation biodiesel production. However, appropriate strain selection is proving challenging due to the significant variation in cellular physiology, metabolic potential and genetics observed even amongst strains deemed morphologically similar. Six strains of Nannochloropsis from the CCAP culture collection were assessed for their lipid productivity and cellular structure, as proxies for oil production and harvesting ease, to assess their suitability as biodiesel production platforms. Differences in growth rate and lipid accumulation across the strains were observed. Nannochloropsis oculata strain 849/7 showed significantly reduced doubling time compared to Nannochloropsis salina strain 849/3, whilst Nannochloropsis oceanica 849/10 produced the highest lipid content. In addition the six strains could be differentiated into 3 distinct classes based on their cell wall thickness, which varied across the strains from 63 to 119 nm and which is independent of both species and geographical isolation location. The importance of these variations in ultrastructure and physiology for biodiesel production is discussed.

Characterization of the Rheological, Mucoadhesive, and Drug Release Properties of Highly Structured Gel Platforms for Intravaginal Drug Delivery

This investigation describes the formulation and characterization of theologically structured vehicles (RSVs) designed for improved drug delivery to the vagina. Interactive, multicomponent, polymeric platforms were manufactured containing hydroxyethylcellulose (HEC, 5% w/w) polyvinylpyrrolidone (PVP, 4% w/w), Pluronic (PL, 0 or 10% w/w), and either polycarbophil (PC, 3% w/w) or poly(methylvinylether-co-maleic anhydride) (Gantrez S97, 3% w/w) as a mucoadhesive agent. The rheological (torsional and dynamic), mechanical (compressional), and mucoadhesive properties were characterized and shown to be dependent upon the mucoadhesive agent used and the inclusion/exclusion of PL. The dynamic theological properties of the gel platforms were also assessed following dilution with simulated vaginal fluid (to mimic in vivo dilution). RSVs containing PC were more rheologically structured than comparator formulations containing GAN. This trend was also reflected in formulation hardness, compressibility, consistency, and syringeability. Moreover, formulations containing PL (10% w/w) were more theologically structured than formulations devoid of PL. Dilution with simulated vaginal fluids significantly decreased rheological structure, although RSVs still retained a highly elastic stnicture (G' > G '' and tan delta <1). Furthermore, RSVs exhibited sustained drug release properties that were shown to be dependent upon their rheological structure. It is considered that these semisolid drug delivery systems may be useful as site-retentive platforms for the sustained delivery of therapeutic agents to the vagina.

Characterisation of the Thermal, Spectroscopic and Drug Dissolution Properties of Mefenamic Acid and Polyoxyethylene–Polyoxypropylene Solid Dispersions

The aim of this study was to investigate the solubility of mefenamic acid (MA), a highly cohesive, poorly water-soluble drug in a copolymer of polyoxyethylene–polyoxypropylene (Lutrol F681), and to understand the effect drug polymer solubility has on in vitro dissolution of MA. Solid dispersions (SD) of MA were prepared by a hot melt method, using Lutrol F681 as a thermoplastic polymeric platform. High-speed differential scanning calorimetry (Hyper-DSC), Raman spectroscopy, powder X-ray diffractometry (PXRD) and hot-stage/?uorescence microscopy were used to assess the solubility of the drug in molten and solid polymer. Drug dissolution studies were subsequently conducted on single-phase solid solutions and biphasic SD using phosphate buffer pH 6.8 as dissolution media. Solubility investigations using Hyper-DSC, Raman spectroscopy and hot-stage microscopy suggested MA was soluble in molten Lutrol F681 up to a concentration of 35% (w/w). Conversely, the solubility in the solidstate matrix was limited to<15% (w/w); determined by Raman spectroscopy, PXRD and ?uorescence microscopy. As expected the dissolution properties of MA were signi?cantly in?uenced by the solubility of the drug in the polymer matrix. At a concentration of 10% (w/w) MA (a single phase solid solution) dissolution of MA in phosphate buffer 6.8 was rapid, whereas at a concentration of 50% (w/w) MA (biphasic SD) dissolution was signi?cantly slower. This study has clearly demonstrated the complexity of drug– polymer binary blends and in particular de?ning the solubility of a drug within a polymeric platform. Moreover, this investigation has demonstrated the signi?cant effect drug solubility within a polymeric matrix has upon the in vitro dissolution properties of solid polymer/drug binary blends.

An ingress and a complete transit of HD80606 b

We have used four telescopes at different longitudes to obtain near-continuous light-curve coverage of the star HD80606 as it was transited by its ~4-MJup planet. The observations were performed during the predicted transit windows around 2008 October 25 and 2009 February 14. Our data set is unique in that it simultaneously constrains the duration of the transit and the planet's period. Our Markov Chain Monte Carlo analysis of the light curves, combined with constraints from radial-velocity data, yields system parameters consistent with previously reported values. We find a planet-to-star radius ratio marginally smaller than previously reported, corresponding to a planet radius of Rp = 0.921 +/- 0.036RJup.

Recent advances in the analysis of behavioural organization and interpretation as indicators of animal welfare

While the incorporation of mathematical and engineering methods has greatly advanced in other areas of the life sciences, they have been under-utilized in the field of animal welfare. Exceptions are beginning to emerge and share a common motivation to quantify 'hidden' aspects in the structure of the behaviour of an individual, or group of animals. Such analyses have the potential to quantify behavioural markers of pain and stress and quantify abnormal behaviour objectively. This review seeks to explore the scope of such analytical methods as behavioural indicators of welfare. We outline four classes of analyses that can be used to quantify aspects of behavioural organization. The underlying principles, possible applications and limitations are described for: fractal analysis, temporal methods, social network analysis, and agent-based modelling and simulation. We hope to encourage further application of analyses of behavioural organization by highlighting potential applications in the assessment of animal welfare, and increasing awareness of the scope for the development of new mathematical methods in this area.

Physicochemical characterisation and drug release properties of celecoxib hot melt extruded glass solutions

Formulation of Celecoxib into solid dosage forms is difficult due to the physical properties of the drug powder. However for the first time, this paper reports on the drug delivery characteristics glass solutions of celecoxib and polyvinylpyrrolidone prepared by hot melt extrusion, together with use of supercritical carbon dioxide to achieve a porous structure, in order to achieve a stable and enhanced drug release.

Tracing Inspiration in Proverbial Material: From 'The Royal Dictionary' (1699 & 1729) of Abel Boyer to 'The English-Irish Dictionary' (1732) of Begley-McCurtin.

This metalexicographic study examines the relationship between the proverbial material in The English-Irish Dictionary (1732) of Begley and McCurtin, Abel Boyer’s The Royal Dictionary (First edition 1699, second edition 1729), and Nathaniel Bailey’s An Universal Etymological English Dictionary (1721). It will show, for the first time, that both the English macrostructure and microstructure of the proverbial entries in Begley and McCurtin (1732) were reproduced directly from Boyer’s dictionary and, in spite of claims to the contrary, the impact of Bailey’s (1721) dictionary was negligible. Furthermore, empirical data gleaned from a comparative linguistic analysis of the various editions of The Royal Dictionary prior to 1732, will prove that it was the second official edition (1729) that was used as the framework for The English-Irish Dictionary. A quantitative and qualitative analysis of the nature of the proverbial entries will also outline the various translation strategies that were used to compose the Irish material— particularly literal translation—and show that there are extremely high-levels of borrowings from Boyer (1729), both in terms of the English entries under the lemma, and the French entries in the comment.