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1.
The objective of this study was to determine the effect of temperature on whole milk density measured at four different temperatures: 5, 10, 15, and 20 °C. A total of ninety-three individual milk samples were collected from morning milking of thirty-two Holstein Friesian dairy cows, of national average genetic merit, once every two weeks over a period of 4 weeks and were assessed by Fourier transform infrared spectroscopy for milk composition analysis. Density of the milk was evaluated using two different analytical methods: a portable density meter DMA35 and a standard desktop model DMA4500M (Anton Paar GmbH, UK). Milk density was analysed with a linear mixed model with the fixed effects of sampling period, temperature and analysis method; triple interaction of sampling period x analysis method x temperature; and the random effect of cow to account for repeated measures. The effect of temperature on milk density (ρ) was also evaluated including temperature (t) as covariate with linear and quadratic effects within each analytic method. The regression equation describing the curvature and density–temperature relationship for the DMA35 instrument was ρ = 1.0338−0.00017T−0.0000122T2 (R2 = 0.64), while it was ρ = 1.0334 + 0.000057T−0.00001T2 (R2 = 0.61) for DMA4500 instrument. The mean density determined with DMA4500 at 5 °C was 1.0334 g cm−3, with corresponding figures of 1.0330, 1.0320 and 1.0305 g cm−3 at 10, 15 and 20 °C, respectively. The milk density values obtained in this study at specific temperatures will help to address any bias in weight–volume calculations and thus may also improve the financial and operational control for the dairy processors in Ireland and internationally.  相似文献   
2.
Scenario based architectural assessment is a well-established approach for assessing architectural designs. However scenario-based methods are not always usable in an industrial context, where in our experience, they can be perceived as complicated and expensive to use. In this paper we explore why this may be the case and define a simpler technique called TARA, which has been designed for use in situations where scenario based methods are unlikely to be successful. The method is illustrated through an experience report that explains how it was applied to the assessment of two quantitative financial analysis systems, and its strengths, weaknesses and relationship to other methods are briefly discussed.  相似文献   
3.
Due to the deficiencies of current commercially available biological bone grafts, alternative bone graft substitutes have come to the forefront of tissue engineering in recent times. The main challenge for scientists in manufacturing bone graft substitutes is to obtain a scaffold that has sufficient mechanical strength and bioactive properties to promote formation of new tissue. The ability to synthesise hydrogel based composite scaffolds using photopolymerisation has been demonstrated in this study. The prepared hydrogel based composites were characterised using techniques including Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy-dispersive X-ray spectrometry (EDX), rheological studies and compression testing. In addition, gel fraction, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), porosity and swelling studies of the composites were carried out. It was found that these novel hydrogel bioglass composite formulations did not display the inherent brittleness that is typically associated with bioactive glass based bone graft materials and exhibited enhanced biomechanical properties compared to the polyethylene glycol hydrogel scaffolds along. Together, the combination of enhanced mechanical properties and the deposition of apatite on the surface of these hydrogel based composites make them an ideal candidate as bone graft substitutes in cancellous bone defects or low load bearing applications.  相似文献   
4.
Neglected tropical diseases caused by parasitic infections are an ongoing and increasing concern. They are a burden to human and animal health, having the most devastating effect on the world′s poorest countries. Building upon our previously reported triazole analogues, in this study we describe the synthesis and biological testing of other novel heterocyclic acetogenin‐inspired derivatives, namely 3,5‐isoxazoles, furoxans, and furazans. Several of these compounds maintain low‐micromolar levels of inhibition against Trypanosoma brucei, whilst having no observable inhibitory effect on mammalian cells, leading to the possibility of novel lead compounds for selective treatment.  相似文献   
5.
Exposure to repeated social stress may cause maladaptive emotional reactions that can be reduced by healthy nutritional supplementation. Histaminergic neurotransmission has a central role in orchestrating specific behavioural responses depending on the homeostatic state of a subject, but it remains to be established if it participates in the protective effects against the insults of chronic stress afforded by a healthy diet. By using C57BL/6J male mice that do not synthesize histamine (Hdc−/−) and their wild type (Hdc+/+) congeners we evaluated if the histaminergic system participates in the protective action of a diet enriched with polyunsaturated fatty acids and vitamin A on the deleterious effect of chronic stress. Behavioural tests across domains relevant to cognition and anxiety were performed. Hippocampal synaptic plasticity, cytokine expression, hippocampal fatty acids, oxylipins and microbiota composition were also assessed. Chronic stress induced social avoidance, poor recognition memory, affected hippocampal long-term potentiation, changed the microbiota profile, brain cytokines, fatty acid and oxylipins composition of both Hdc−/− and Hdc+/+ mice. Dietary enrichment counteracted stress-induced deficits only in Hdc+/+ mice as histamine deficiency prevented almost all the diet-related beneficial effects. Interpretation: Our results reveal a previously unexplored and novel role for brain histamine as a mediator of many favorable effects of the enriched diet. These data present long-reaching perspectives in the field of nutritional neuropsychopharmacology.  相似文献   
6.
We have calculated the optical absorption for InGaNAs and GaNSb using the band anticrossing (BAC) model and a self-consistent Green’s function (SCGF) method. In the BAC model, we include the interaction of isolated and pair N levels with the host matrix conduction and valence bands. In the SCGF approach, we include a full distribution of N states, with non-parabolic conduction and light-hole bands, and parabolic heavy-hole and spin-split-off bands. The comparison with experiments shows that the first model accounts for many features of the absorption spectrum in InGaNAs; including the full distribution of N states improves this agreement. Our calculated absorption spectra for GaNSb alloys predict the band edges correctly but show more features than are seen experimentally. This suggests the presence of more disorder in GaNSb alloys in comparison with InGaNAs.  相似文献   
7.
A number of Member States of the European Union (EU) have introduced market-based policy portfolios based on quantified energy savings obligations on energy distributors or suppliers, possibly coupled with certification of project-based energy savings (via white certificates), and the option to trade the certificates or obligations. The paper provides an up-to-date review and analysis of results to date of white certificate schemes in the EU.  相似文献   
8.
By triangulating analyses of content and reception with a focus on production, this article attempts to understand the dynamics of and underlying reasons for the media stigmatisation of place. The research described contributes to a body of work examining how mass media and other social forces factor in the creation of negative stereotypes that damage the reputations of the places in which the poor reside. The overarching framework of understanding, provided by Goffman’s theory of stigma, is complemented by two further inter-related theoretical approaches, namely Social Exclusion and Political Economy. Combining analyses of media production (practices), media content (discourses) and audience reception (beliefs, attitudes), we analyse the representation of one of Ireland’s most deprived public housing estates in the print and broadcast media. Having established the stigmatising character and impact of national and local media content via this tripartite methodology, we focus on identifying and explaining the media practices that serve to (re)produce the estate’s ‘spoiled identity’. Our analysis of journalists’ explanations for these practices identifies the commercial realities, which progressively influence media production, as directly impacting media producers’ relationships with, and depictions of, poor places. We conclude by examining debates regarding the potential for rehabilitating a spoiled identity.  相似文献   
9.
Agile Practices Reduce Distance in Global Software Development   总被引:2,自引:0,他引:2  
This article explores how agile practices can reduce three kinds of “distance” - temporal, geographical, and sociocultural - in global software development (GSD). On the basis of two in-depth case studies, specific Scrum and eXtreme Programming (XP) practices are found to be useful for reducing communication, coordination, and control problems that have been associated with GSD.  相似文献   
10.
The new economy is the result of the information revolution, of shrinking and ever more powerful computers, and the emergence of an efficient, ubiquitous and invisible communications infrastructure. It is characterized by three distinctive attributes: it is global, it favors intangible things—ideas, information, knowledge, relationships, and it is intensely inter-linked. As more and more organizations prepare to go digital, only few of them really seem to recognize what implications this transition will have on their business processes and on the organization as a whole. The transformation involves much more than setting up a digital infrastructure and requires even more than the ability to enter into a virtual collaboration with other partners. Organizations need to become smart, i.e. knowledge driven, internetworked, dynamically adaptive to new organizational forms and practices, learning as well as agile in their ability to create and exploit the opportunities offered by the digital economy. The article considers technologies and trends towards inter-operable tools for organizational agility and flexibility based on distributed business operations. The European Commission has been supporting these developments through its various research programmes since the early 1980s. Besides the notable research and technological development (RTD) achievements, important progress has also been made in the area of standardization and through consensus building between the research and business communities in Europe. It is further recognised that technology alone will not be able to sustain the creative potential of the digital economy if the socio-economic, the legal and regulatory frameworks are not adequately taken into account.  相似文献   
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