567 research outputs found

    Linear data structures for storage allocation in attribute evaluators

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    Practical and theoretical results have been found concerning the use of global storage allocation for the instances of applied occurrences of an attribute.\ud The practical results focus on the necessary and sufficient conditions to decide at evaluator construction time whether an evaluator can allocate the instances of an applied occurrence to a number of global variables, stackes and queues. Checking these conditions takes polynomial time for a simple multi-visit evaluator and exponential time for an absolutely non-circular evaluator.\ud The theoretical results are concerned with the data structures that are required for the global storage allocation of the instances of applied occurrences in simple multi-X evaluators, where X € {pass, sweep, visit}. For this purpose, the general class of basic linear data structures is introduced. This class of data structures can also be used to explore the theoretical possibilities and limitations of storage allocation techniques in domains other than attribute grammars

    Endocrine Factors, Retinal Vessels, and Risk of Dementia

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    First described 100 years ago by Alois Alzheimer, the clinico-pathological entity that we now call Alzheimer disease was initially presented as a clinically unusual type of dementia. 1 Nowadays, Alzheimer disease is recognized as the main cause of dementia and one of the most disabling and burdensome health conditions worldwide.2,3 The number of people affected by dementia is estimated to double every 20 years to over 80 million by 2040.3 This will not only affect patients and their caregivers, but will also put an enormous demand on health care and welfare resources

    Poly(amido amine)s as Gene Delivery Vectors: Effects of Quaternary Nicotinamide Moieties in the Side Chains

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    To evaluate the effect of quaternary nicotinamide pendant groups on gene delivery properties, a series of poly(amido amine) (co)polymers were synthesized by Michael addition polymerization of N, N-cystaminebisacrylamide with variable ratios of 1-(4-aminobutyl)-3-carbamoylpyridinium (Nic-BuNH2), and tert-butyl-4-aminobutyl carbamate (BocNH-BuNH2), yielding poly(amido amine)s (NicX-NHBoc) with X=0, 10, 30, and 50 % of quaternary nicotinamide groups in the polymer side chains. Deprotection of the pendant Boc-NH groups afforded an analogous series of polymers (NicX-NH2) with higher charge density (due to the presence of protonated primary amino groups in the side chains) and subsequent acetylation yielded a series of polymers (NicX-NHAc) of lower hydrophobicity than the Boc-protected polymers. The polymers with the Boc-protected or the acetylated amino groups showed high buffer capacity in the range pH 5.1-7.4, which is a property that can contribute to endosomal escape of polyplexes. The presence of quaternary nicotinamide groups has distinct beneficial effects on the gene vector properties of these polymers. The polymers containing 30 % of quaternary nicotinamide groups in their side chains condense DNA into small, nanosized particles (200 nm) with positive surface charge (+15 mV). Fluorescence experiments using ethidium bromide as a competitor showed that the quaternary nicotinamide groups intercalate with DNA, contributing to a more intimate polymer-DNA binding and shielding. Polyplexes of nicotinamide-functionalized poly(amido amine)s NicX-NHBoc and NicX-NHAc, formed at 12/1 polymerDNA mass ratio, efficiently transfect COS-7 cells with efficacies up to four times higher than that of PEI (Exgen 500), and with essentially absence of cytotoxicity. NicX-NH2 polymers, possessing protonated primary amino groups in their side chains, have a higher cytotoxicity profile under these conditions, but at lower 3/1 polymer-DNA mass ratio also these polymers are capable of efficient transfection, while retaining full cell viability

    Renormalization group flows for gauge theories in axial gauges

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    Gauge theories in axial gauges are studied using Exact Renormalisation Group flows. We introduce a background field in the infrared regulator, but not in the gauge fixing, in contrast to the usual background field gauge. It is shown how heat-kernel methods can be used to obtain approximate solutions to the flow and the corresponding Ward identities. Expansion schemes are discussed, which are not applicable in covariant gauges. As an application, we derive the one-loop effective action for covariantly constant field strength, and the one-loop beta-function for arbitrary regulator

    Angiotensin II type 2 receptors and cardiac hypertrophy in women with hypertrophic cardiomyopathy

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    The development of left ventricular hypertrophy in subjects with hypertrophic cardiomyopathy (HCM) is variable, suggesting a ro

    Random and block copolymers of bioreducible poly(amido amine)s with high- and low-basicity amino groups: study of DNA condensation and buffer capacity on gene transfection

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    Poly(amido amine) (SS-PAA) random and block copolymers having bioreducible disulfide bonds in the main chain and amino groups with distinctly different basicity in the side chain were designed and synthesized by Michael addition polymerization between N, N′-cystaminebisacrylamide (CBA) and two amine monomers, i.e., histamine (HIS) and 3-(dimethylamino)-1-propylamine (DMPA). Copolymers containing variable HIS/DMPA ratios show higher ability to bind DNA than p(CBA-HIS) homopolymer and condense DNA into the polyplexes with particle sizes (< 150 nm) that are smaller than polyplexes of p(CBA-HIS) (not, vert, similar 220 nm). The buffer capacities of the copolymers increase with increasing HIS/DMPA ratio. These copolymers are able to transfect COS-7 cells in vitro with efficiencies that increase with increasing HIS/DMPA ratio. The random and block copolymers at a HIS/DMPA ratio of 70/30 combines optimal DNA condensation capability and buffer capacity, thereby inducing higher transfection efficiency in the absence and presence of serum as compared to p(CBA-HIS) homopolymer. Moreover, random and block copolymers show a similar transfection capacity, but both have higher capacity than the physical mixtures of p(CBA-HIS) and p(CBA-DMPA) homopolymers. XTT assay reveals that the polyplexes of the SS-PAA copolymers have essentially low cytotoxicity when the highest transfection activity is observed
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