825 research outputs found

    Finite size effects and scaling in lattice CP(N-1)

    Full text link
    We present model predictions for the spectrum of CPN−1CP^{N-1} in a periodic box and use them to interpret the strong finite size effects observed in lattice simulations at medium values of NN. The asymptotic scaling behaviour of alternative lattice actions is discussed along with some aspects of multigrid algorithm efficiency.Comment: 6 pages of text plus 2 pages of figures, Liverpool Preprint LTH28

    Leuk dat je als CEO de onderneming duurzaam wilt maken, maar niet ten koste van het rendement!

    Get PDF
    Coherent privaatrech

    Uniform kernelization complexity of hitting forbidden minors

    Get PDF
    The F-MINOR-FREE DELETION problem asks, for a fixed set F and an input consisting of a graph G and integer k, whether κ vertices can be removed from G such that the resulting graph does not contain any member of F as a minor. At FOCS 2012, Fomin et al. showed that the special case when F contains at least one planar graph has a kernel of size f (F) · κg(F) for some functions f and g. They left open whether this PLANAR F-MINOR-FREE DELETION problem has kernels whose size is uniformly polynomial, of the form f (F) · κc for some universal constant c. We prove that some PLANAR F-MINOR-FREE DELETION problems do not have uniformly polynomial kernels (unless NP ⊆ coNP/poly), not even when parameterized by the vertex cover number. On the positive side, we consider the problem of determining whether κ vertices can be removed to obtain a graph of treedepth at most η. We prove that this problem admits uniformly polynomial kernels with O(κ6) vertices for every fixed η.</p

    Cathepsin L of Triatoma brasiliensis (Reduviidae, Triatominae): Sequence characterization, expression pattern and zymography

    Get PDF
    AbstractTriatoma brasiliensis is considered one of the main vectors of Chagas disease commonly found in semi-arid areas of northeastern Brazil. These insects use proteases, such as carboxypeptidase B, aminopeptidases and different cathepsins for blood digestion. In the present study, two genes encoding cathepsin L from the midgut of T. brasiliensis were identified and characterized. Mature T. brasiliensis cathepsin L-like proteinases (TBCATL-1, TBCATL-2) showed a high level of identity to the cathepsin L-like proteinases of other insects, with highest similarity to Rhodnius prolixus. Both cathepsin L transcripts were highly abundant in the posterior midgut region, the main region of the blood digestion. Determination of the pH in the whole intestine of unfed T. brasiliensis revealed alkaline conditions in the anterior midgut region (stomach) and acidic conditions in the posterior midgut region (small intestine). Gelatine in-gel zymography showed the activity of at least four distinct proteinases in the small intestine and the cysteine proteinase inhibitors transepoxysuccinyl-l-leucylamido-(4-guanidino)butane (E-64) and cathepsin B inhibitor and N-(l-3-trans-propylcarbamoyl-oxirane-2-carbonyl)-l-isoleucyl-l-proline (CA-074) were employed to characterize enzymatic activity. E-64 fully inhibited cysteine proteinase activity, whereas in the samples treated with CA-074 residual proteinase activity was detectable. Thus, proteolytic activity could at least partially be ascribed to cathepsin L. Western blot analysis using specific anti cathepsin L antibodies confirmed the presence of cathepsin L in the lumen of the small intestine of the insects

    Effecten van mosselvisserij op de bodemstructuur, een analyse van Sidescan sonar opnames

    Get PDF
    Mosselzaadbanken in de Waddenzee worden bevist. In 2006 is een onderzoek gestart naar de effecten van mosselzaadvisserij op sublitorale natuurwaarden, het PRODUS onderzoek. Omdat de biodiversiteit in de Waddenzee nauw samenhangt met de driedimensionale structuur van de zeebodem wordt binnen PRODUS het effect van visserij op deze structuur bestudeerd aan de hand van sidescan sonar opnames die voor en na visserij worden uitgevoer

    Groei en gedrag van schelpdieren in vijverteelt, samenvattend eindrapport Zeeuwse tong werkpakket 2

    Get PDF
    De binnendijkse kweek van schelpdieren en micro-algen is in het kader van het project Zeeuwse Tong onderzocht en uitgetest op verschillende schaalniveaus. In de pilots is op praktijkschaal getest wat er nodig is voor een commercieel haalbare productie. In één van de pilots (Colijnsplaat) zijn de algen en schelpdieren gekweekt in samenhang met zager en tong kweek, in de andere pilots (Zeeland Aquacultuur en Wilhelminapolder) was de kweek gericht op algen en schelpdieren. In het laboratorium en in nagebootste ecosystemen (mesocosms) is een reeks deelvragen onderzocht, onder meer wat betreft de benodigdheden voor algenkweek en de kwaliteit van algen voor schelpdieren. In de pilots zijn specifieke proces metingen uitgevoerd. De resultaten van de procesmetingen en de lab en mesocosm experimenten worden in onderhavig rapport samengevat

    Epilepsy surgery in tuberous sclerosis: The Dutch experience

    Get PDF
    SummaryIntroductionEpilepsy associated with tuberous sclerosis complex (TSC) is drug resistant in more than half of the patients. Epilepsy surgery may be an alternative treatment option, if the epileptogenic tuber can be identified reliably and if seizure reduction is not at the expense of cognitive or other functions. We report the pre-surgical identification of the epileptogenic tuber and post-surgical outcome of patients with TSC in The Netherlands.MethodsTwenty-five patients underwent the pre-surgical evaluation of the Dutch Comprehensive Epilepsy Surgery Programme, including a detailed seizure history, interictal and ictal video EEG registrations, 3D FLAIR MRI scans and neuropsychological testing. Suitability of the candidates was decided in consensus. Seizure outcome, scored with the Engel classification, and cognition were reassessed at fixed post-surgery intervals.ResultsEpilepsy surgery was performed in six patients. At follow-up, four patients had Engel classification 1, two had classification 4. Improved development and behaviour was perceived by the parents of two patients. Epilepsy surgery was not performed in 19 patients because seizures were not captured, ictal onset zones could not be localised or were multiple, interictal EEG, video EEG and MEG results were not concordant, or seizure burden had diminished during decision making. A higher cognition index was found in the surgical patients compared to the non-surgical candidates.ConclusionsEpilepsy surgery can be performed safely and successfully in patients in whom semiology, interictal EEG, ictal EEG, MEG and the location of tubers are concordant. In other cases the risk of surgery should be weighed against the chance of seizure relief and in case of children subsequent impact on neurodevelopment
    • …
    corecore