9,167 research outputs found
A study of the enzymatic hydrolysis of fish frames using model systems
A model system was employed to study the operating conditions and primary parameters of enzymic hydrolysis of cod proteins. Pancreatin, papain, and bromelain were used to hydrolyse minced cod fillets under controlled conditions and with the rate of hydrolysis being continually monitored via both the pH-stat and TNBS method. The two methods were compared and evaluated. The rate of protein solubilisation was plotted against the degree of hydrolysis (DH). Dry fish protein hydrolysate (FPH) powders having short, medium and high degrees of hydrolysis (DH of approximately 8%, 11% and 16% respectively) were produced and analysed for their molecular weight distribution, using size exclusion chromatography. Almost complete protein solubilisation (75 g soluble protein per kg hydrolysis solution) could be achieved within an hour, at 40°C, at 1% enzyme/substrate ratio (w/w) with papain and bromelain. The pH-stat was found capable of continuously following the rate of hydrolysis but only at low DH. The TNBS could be accurately used even at high DH to estimate the percentage of the peptide bonds cleaved, but required chemical analysis of withdrawn samples
Research in progress: Assessing marine radiocarbon reservoir effect variation in greater Utqiaġvik, Alaska
No abstract available
Enzymatic hydrolysis of fish frames using pilot plant scale systems
Papain was used to hydrolyse fish frames under controlled conditions at a batch-pilot plant scale-process, for the pro-duction of fish protein hydrolysates (FPH). Mass balance calculations were carried out so that the rate of hydrolysis, rate of protein solubilisation and yields could be estimated. Almost complete hydrolysis could be achieved in 1 hour, at 40°C, with no pH adjustment, at 0.5% (5 g·kg−1) enzyme to substrate ratio (E/S, were S is Kjeldahl protein) using whole fish frames (including heads and flaps). This was achieved both with the addition of water (1/1 to 2/1 frames/water) but more importantly from commercial considerations without the initial addition of water (after mincing of the fish mate-rial). The degree of protein solubilisation ranged between 71% - 86% w/w. Four different processes are described, namely: 1) a soluble spray-dried FPH powder; 2) a liquid FPH; 3) a partly soluble, spray dried FPH powder and; 4) a crude, drum-dried protein for animal consumption. The amino acid profile of the FPH was identical to that of the par-ent substrate (fish frames)
Independent confirmation of {\beta} Pictoris b imaging with NICI
Context. {\beta} Pictoris b is one of the most studied objects nowadays since
it was identified with VLT/NaCo as a bona-fide exoplanet with a mass of about 9
times that of Jupiter at an orbital separation of 8-9 AU. The link between the
planet and the dusty disk is unambiguously attested and this system provides an
opportunity to study the disk/planet interactions and to constrain formation
and evolutionary models of gas giant planets. Still, {\beta} Pictoris b had
never been confirmed with other telescopes so far. Aims. We aimed at an
independent confirmation using a different instrument. Methods. We retrieved
archive images from Gemini South obtained with the instrument NICI, which is
designed for high contrast imaging. The observations combine coronagraphy and
angular differential imaging and were obtained at three epochs in Nov. 2008,
Dec. 2009 and Dec. 2010. Results. We report the detection with NICI of the
planet {\beta} Pictoris b in Dec. 2010 images at a separation of 404 \pm 10 mas
and P A = 212.1 \pm 0.7{\deg} . It is the first time this planet is observed
with a telescope different than the VLT.Comment: Letter accepted for publication in Astronomy and Astrophysics on Feb.
21, 2013. 4 pages, 2 figure
Tools for quantitative form description : an evaluation of different software packages for semi-landmark analysis
The challenging complexity of biological structures has led to the development of several methods for quantitative analyses of form. Bones are shaped by the interaction of historical (phylogenetic), structural, and functional constrains. Consequently, bone shape has been investigated intensively in an evolutionary context. Geometric morphometric approaches allow the description of the shape of an object in all of its biological complexity. However, when biological objects present only few anatomical landmarks, sliding semi-landmarks may provide good descriptors of shape. The sliding procedure, mandatory for sliding semi-landmarks, requires several steps that may be time-consuming. We here compare the time required by two different software packages ('Edgewarp' and 'Morpho') for the same sliding task, and investigate potential differences in the results and biological interpretation. 'Morpho' is much faster than 'Edgewarp,' notably as a result of the greater computational power of the 'Morpho' software routines and the complexity of the 'Edgewarp' workflow. Morphospaces obtained using both software packages are similar and provide a consistent description of the biological variability. The principal differences between the two software packages are observed in areas characterized by abrupt changes in the bone topography. In summary, both software packages perform equally well in terms of the description of biological structures, yet differ in the simplicity of the workflow and time needed to performthe analyses
Improving e-therapy for mood disorders among lesbians and gay men
Introduction
This toolkit provides the first comprehensive set of guidelines for tailoring mood-disorder e-therapies to the needs of same-sex attracted people. It gives developers of e-therapies a set of practical recommendations for adjusting e-therapies to more effectively accommodate lesbians and gay men. These recommendations are supported by in-depth research that was designed specifically to inform this toolkit.
Summaries of this research are provided in the toolkit and detailed findings are available in published research articles. This toolkit also provides information on the mental health-related challenges that are often faced by same-sex attracted people and links readers to key resources and organisations for further information. Checklists and other tools are included as aids for developers to assess the inclusiveness and relevance of e-therapies to lesbians and gay men. In short, this toolkit contains an extensive set of tools and explains why and how they could be implemented
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