1,428 research outputs found
From Grain to Feed
Horse beans are used as an example of grain, which have potentials to substitute fish meal in fish feed. After several grinding and fractionation steps it was possible to obtain a protein-rich horse bean fraction with a yield of 19 %. This fraction contained 55.9 % protein. The high protein content together with the amino acid profile makes the fraction very suitable as a substitute to fish meal in fish feed. The protein-rich fraction was used as a successful additive in extruded fish pellets
Attraction and diffusion in nature-inspired optimization algorithms
Nature-inspired algorithms usually use some form of attraction and diffusion as a mechanism for exploitation and exploration. In this paper, we investigate the role of attraction and diffusion in algorithms and their ways in controlling the behaviour and performance of nature-inspired algorithms. We highlight different ways of the implementations of attraction in algorithms such as the firefly algorithm, charged system search, and the gravitational search algorithm. We also analyze diffusion mechanisms such as random walks for exploration in algorithms. It is clear that attraction can be an effective way for enhancing exploitation, while diffusion is a common way for exploration. Furthermore, we also discuss the role of parameter tuning and parameter control in modern metaheuristic algorithms, and then point out some key topics for further research
Approximate solutions in space mission design
In this paper, we address multi-objective space mission design problems. From a practical point of view, it is often the case that,during the preliminary phase of the design of a space mission, the solutions that are actually considered are not 'optimal' (in the Pareto sense)but belong to the basin of attraction of optimal ones (i.e. they are nearly
optimal). This choice is motivated either by additional requirements that the decision maker has to take into account or, more often, by robustness considerations. For this, we suggest a novel MOEA which is a modification of the well-known NSGA-II algorithm equipped with a recently
proposed archiving strategy which aims at storing the set of approximate solutions of a given MOP. Using this algorithm we will examine some space trajectory design problems and demonstrate the benefit of the novel approach
Undersøgelse af sammenhængen mellem udviklingen af skarvkolonien ved Toftesø og forekomsten af fladfiskeyngel i Ålborg Bugt
Bacterial viruses enable their host to acquire antibiotic resistance genes from neighbouring cells
Prophages are quiescent viruses located in the chromosomes of bacteria. In the human
pathogen, Staphylococcus aureus, prophages are omnipresent and are believed to be responsible
for the spread of some antibiotic resistance genes. Here we demonstrate that release of
phages from a subpopulation of S. aureus cells enables the intact, prophage-containing
population to acquire beneficial genes from competing, phage-susceptible strains present in
the same environment. Phage infection kills competitor cells and bits of their DNA are
occasionally captured in viral transducing particles. Return of such particles to the prophagecontaining
population can drive the transfer of genes encoding potentially useful traits such
as antibiotic resistance. This process, which can be viewed as ‘auto-transduction’, allows
S. aureus to efficiently acquire antibiotic resistance both in vitro and in an in vivo virulence
model (wax moth larvae) and enables it to proliferate under strong antibiotic selection
pressure. Our results may help to explain the rapid exchange of antibiotic resistance genes
observed in S. aureus
Discreet heterotrophs:green plants that receive fungal carbon through <i>Paris-type </i>arbuscular mycorrhiza
Hepatic Ultrasonography Compared with Computed Tomography and Magnetic Resonance Imaging at Diagnosis of Metastatic Uveal Melanoma
Purpose To evaluate the consistency of hepatic ultrasonography (US) with staging computed tomography (CT) and magnetic resonance imaging (MRI), to analyze why US was inconsistent with CT/MRI, and to compare CT/MRI. DESIGN Reliability analysis. METHODS Two hundred fifteen patients whose primary uveal melanoma was managed in the Helsinki University Hospital and who were diagnosed with hepatic metastases by US within 60 days of staging CT/MRI from January 1999 to December 2016, were included. Patients attended a real-life follow-up schedule including hepatic US, liver function tests (LFT), and a confirmatory CT/MRI. We evaluated the consistency of US with staging CT/MRI regarding the presence and number of metastases. RESULTS The enrolled patients underwent 215 US, 167 CT, and 69 MRI examinations, and 67% of them had biopsy-confirmed metastases. Screening was regular for 98% of the patients, and 66% were asymptomatic. US was fully consistent with CT/MRI in detecting metastases in 113 (53%) patients, in 63 (29%) CT/MRI showed more metastases, and in 16 (7%) less metastases than US. CT/MRI was inconsistent with US in 23 (11%) patients. The sensitivity of US in detecting metastases was 96% (95% confidence interval, 92-98). US failed to suggest metastases in 10 patients. LFT were abnormal in six of them, and a newly-detected hepatic lesion was present by US in four. CONCLUSIONS Hepatic US is a sensitive screening modality in detecting metastases in patients with primary uveal melanoma, if combined with LFT and in case of any new detected lesion, a confirmatory MRI.Peer reviewe
Artefacts: a multi-voiced collection of paraphernalia, documentation and reflection on the space and words for dancers work-week
Artefacts is a multi-voiced collection of paraphernalia, documentation and reflection relating to a week-long event (July 2015) that revolved around the work of dancers and poets Julyen Hamilton (Spain) and Billie Hanne (Belgium). Hosted by Chisenhale Dance Space, London, and curated by dance-artist Antonio de la Fe and artist/scholar Robert Vesty, the Space and Words for Dancers event consisted of a six-day workshop for 25 dancers led by Hamilton and Hanne that focused on the use of space and words in performance; two solo performances by Hamilton (Play) and Hanne (Deep Brown Sea); an Evening Talk event with Hamilton and Hanne talking in-depth about their work and the making of poetry and dance; as well as an open-to-the-public Discussion Day that used Open Space Technology (OST) as an organizing tool to discuss the question ‘What skills are required of the dancer and poet to produce poetry and dance in performance?’. Artefacts is a collaboration with graphic designer Tomas Di Giovanni and includes Billie’s Outline, a rationale for bringing words and dance together in the workshop, written by Hanne; poetry by Hamilton and Hanne composed especially for this Words and Dance issue of Choreographic Practices; programme notes from Play and Deep Brown Sea; a reflective piece by Antonio de la Fe on the nature of work for the dance artist as performer entitled That You Took the Workshop Doesn’t Mean You Have Done the Work; a photo-essay by resident photographer Maria Andrews; extracts from the transcript of Evening Talk collated around the headings On Poetry and Dance, On Space, On Making Pieces, On Repeating Pieces and On How it Works; and finally, a nod to the discussion day. Overall, the aim of Artefacts is to pull together some coordinates of the different and multifarious strands of activity that went into and came out of the Space and Words for Dancers work-week, which inspired this special Words and Dance edition of Choreographic Practices, but to do so in a way that might begin to perform and applaud the aesthetic quality of the work with space and words
The heme sensing response regulator HssR in Staphylococcus aureus but not the homologous RR23 in Listeria monocytogenes modulates susceptibility to the antimicrobial peptide plectasin
<p>Abstract</p> <p>Background</p> <p>Host defence peptides (HDPs), also known as antimicrobial peptides (AMPs), have emerged as potential new therapeutics and their antimicrobial spectrum covers a wide range of target organisms. However, the mode of action and the genetics behind the bacterial response to HDPs is incompletely understood and such knowledge is required to evaluate their potential as antimicrobial therapeutics. Plectasin is a recently discovered HDP active against Gram-positive bacteria with the human pathogen, <it>Staphylococcus aureus </it>(<it>S. aureus</it>) being highly susceptible and the food borne pathogen, <it>Listeria monocytogenes </it>(<it>L. monocytogenes</it>) being less sensitive. In the present study we aimed to use transposon mutagenesis to determine the genetic basis for <it>S. aureus </it>and <it>L. monocytogenes </it>susceptibility to plectasin.</p> <p>Results</p> <p>In order to identify genes that provide susceptibility to plectasin we constructed bacterial transposon mutant libraries of <it>S. aureus </it>NCTC8325-4 and <it>L. monocytogenes </it>4446 and screened for increased resistance to the peptide. No resistant mutants arose when <it>L. monocytogenes </it>was screened on plates containing 5 and 10 fold Minimal Inhibitory Concentration (MIC) of plectasin. However, in <it>S. aureus</it>, four mutants with insertion in the heme response regulator (<it>hssR</it>) were 2-4 fold more resistant to plectasin as compared to the wild type. The <it>hssR </it>mutation also enhanced resistance to the plectasin-like defensin eurocin, but not to other classes of HDPs or to other stressors tested. Addition of plectasin did not influence the expression of <it>hssR </it>or <it>hrtA</it>, a gene regulated by HssR. The genome of <it>L. monocytogenes </it>LO28 encodes a putative HssR homologue, RR23 (in <it>L. monocytogenes </it>EGD-e lmo2583) with 48% identity to the <it>S. aureus </it>HssR, but a mutation in the <it>rr23 </it>gene did not change the susceptibility of <it>L. monocytogenes </it>to plectasin.</p> <p>Conclusions</p> <p><it>S. aureus </it>HssR, but not the homologue RR23 from <it>L. monocytogenes</it>, provides susceptibility to the defensins plectasin and eurocin. Our data suggest that a functional difference between response regulators HssR and RR23 is responsible for the difference in plectasin susceptibility observed between <it>S. aureus </it>and <it>L. monocytogenes</it>.</p
Attraction and diffusion in nature-inspired optimization algorithms
Nature-inspired algorithms usually use some form of attraction and diffusion as a mechanism for exploitation and exploration. In this paper, we investigate the role of attraction and diffusion in algorithms and their ways in controlling the behaviour and performance of nature-inspired algorithms. We highlight different ways of the implementations of attraction in algorithms such as the firefly algorithm, charged system search, and the gravitational search algorithm. We also analyze diffusion mechanisms such as random walks for exploration in algorithms. It is clear that attraction can be an effective way for enhancing exploitation, while diffusion is a common way for exploration. Furthermore, we also discuss the role of parameter tuning and parameter control in modern metaheuristic algorithms, and then point out some key topics for further research
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