96,187 research outputs found

    Tests of random density models of terrestrial planets

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    Random density models are analyzed to determine the low degree harmonics of the gravity field of a planet, and therefrom two properties: an axiality P_l , the percent of the degree variance in the zonal term referred to an axis through the maximum for degree l; and an angularity E_(ln) , the angle between the maxima for two degrees l, n. The random density distributions give solutions reasonably consistent with the axialities and angularities for the low degrees, l < 5, of Earth, Venus, and Moon, but not for Mars, which has improbably large axialities and small angularities. Hence the random density model is an unreliable predictor for the non‐hydrostatic second‐degree gravity of Mars, and thus for the moment‐of‐inertia, which is more plausibly close to 0.365MR^2

    Adiabat_1ph: A new public front-end to the MELTS, pMELTS, and pHMELTS models

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    The program adiabat_1ph is a simple text-menu driver for subroutine versions of the algorithms MELTS, pMELTS, and pHMELTS [Asimow et al., 2004; Ghiorso et al., 2002; Ghiorso and Sack, 1995]. It may be used to calculate equilibrium assemblages along a thermodynamic path set by the user and can simultaneously calculate trace element distributions. The MELTS family of algorithms is suitable for multicomponent systems, which may be anhydrous, water-undersaturated, or water-saturated, with the options of buffering oxygen fugacity and/or water activity. A wide variety of calculations can be performed either subsolidus or with liquid(s) present; melting and crystallization may be batch, fractional, or continuous. The software is suitable for Linux, MacOS X, and Windows, and many aspects of program execution are controlled by environment variables. Perl scripts are also provided that may be used to invoke adiabat_1ph with some command line options and to produce output that may be easily imported into spreadsheet programs, such as Microsoft Excel. Benefits include a batch mode, which allows almost complete automation of the calculation process when suitable input files are written. This technical brief describes version 1.04, which is provided as ancillary material. Binaries, scripts, documentation, and example files for this and future releases may be downloaded at http://www.gps.caltech.edu/~asimow/adiabat. On a networked computer, adiabat_1ph automatically checks whether a newer version is available

    Antimicrobial antagonists against food pathogens; a bacteriocin perspective

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    peer-reviewedEfforts are continuing to find novel bacteriocins with enhanced specificity and potency. Traditional plating techniques are still being used for bacteriocin screening studies, however, the availability of ever more bacterial genome sequences and the use of in silico gene mining tools have revealed novel bacteriocin gene clusters that would otherwise have been overlooked. Furthermore, synthetic biology and bioengineering-based approaches are allowing scientists to harness existing and novel bacteriocin gene clusters through expression in different hosts and by enhancing functionalities. The same principles apply to bacteriocin producing probiotic cultures and their application to control pathogens in the gut. We can expect that the recent developments on bacteriocins from Lactic Acid Bacteria (LAB) described here will contribute greatly to increased commercialisation of bacteriocins in food systems.This work was funded by the Alimentary Pharmabiotic Centre, a research centre funded by Science Foundation Ireland (SFI), through the Irish Government’s National Development Plan. The authors and their work were supported by SFI (grant no. 12/RC/2273

    Towards zero solid waste: utilising tannery waste as a protein source for poultry feed

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    Zero waste is now a strongly emerging issue for sustainable industrial development where minimisation and utilisation of waste are a priority in the leather industry. In a tannery hides and skins converted in to leather through various processes. Approximately 20% (w/w) of the chrome containing tannery solid waste (TSW) is generated from one tonne of raw hides and skins. However, tannery solid waste may also be a resource if it is managed expertly as we move towards zero waste. This research illustrates the potential of tannery solid waste as a poultry feed additive. An oxidation method was used to achieve 95% of dechroming rate of chrome tanned waste followed with thermal and enzymatic treatment to produce gelatin solution and collagen concentrates. The thermal stability and fibre structure of samples were analysed by Differential Scanning Calorimeter (DSC) and Scanning Electron Microscope (SEM). Protein content and fourteen amino acid concentrations were determined using amino acid analysis. High Performance Liquid Chromatography (HPLC) was used to compare the amino acid composition with wheat and soya bean meal that is conventionally used in poultry feed. The nutrient requirements for poultry feed vary according to the purpose for which they have been developed. The high content of arginine, leucine, threonine, serine and methionine in the extract were of a sufficient level for poultry feed. Hexavalent chromium test was performed and showed that levels of the metal were low enough to be used in feed additives. In addition, the extracted product showed 75% digestibility (in vitro) and appears that treated TSW may be utilised in poultry feed, this demonstrates a clear example of waste utilisation. In Bangladesh plans are being formed to use the extract in poultry feed production

    Understanding practitioner professionalism in Aboriginal and Torres Strait Islander health: lessons from student and registrar placements at an urban Aboriginal and Torres Strait Islander primary health care service

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    Aboriginal and Torres Strait Islander peoples continue to be pathologised in medical curriculum, leaving graduates feeling unequipped to effectively work cross-culturally. These factors create barriers to culturally safe health care for Aboriginal and Torres Strait Islander peoples. In this pilot pre-post study, we followed the learning experiences of 7 medical students and 4 medical registrars undertaking clinical placements at an urban Aboriginal and Torres Strait Islander primary health care service in 2014. Through analysis and comparison of pre- and post-placement responses to a paper-based case study of a fictitious Aboriginal patient, we identified four learning principles for medical professionalism: student exposure to nuanced, complex and positive representations of Aboriginal peoples; positive practitioner role modelling; interpersonal skills that build trust and minimise patient-practitioner relational power imbalances; and, knowledge, understanding and skills for providing patient centred, holistic care. Though not exhaustive, these principles can increase the capacity of practitioners to foster culturally safe and optimal health care for Aboriginal peoples. Furthermore, competence and effectiveness in Aboriginal health contexts is an essential component of medical professionalism
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