Nature of Viscoelasticity in Lamellar Block Copolymers: Contraction Correlated to Strain Localization

We determined the local strain profile in sheared lamellar block copolymers. A trilayer model, based on elastic brushes separated by viscous interpenetration zones, captures the rheological response of these materials and provides a measure of the relative contributions of elastic versus viscous strain. The elastic chain distortions were evident from a reversible lamellar contraction, as measured from in situ small-angle x-ray scattering. The contraction was directly correlated to the elastic strain from our trilayer model; three distinct diblock copolymers conform to the predicted relationship, thus suggesting universal behavior

Environmental risk assessment studies on new plant protection products which have been elaborated from coniferous tree bark

ArticleNowadays there are still various chemical pesticides being applied in the course of ensuring plant protection. Since 2010, we have been working on the development of new, environmentally-friendly plant protection products which will provide an effective tool against pathogenic fungi and bacteria which cause disease in crop plants. The specific aim of this study was to evaluate a risk assessment for new plant protection products that have been elaborated on the basis of coniferous tree bark. Various products were tested which are extracted during the processing of wood bark from pine (Pinus sylvestris L.) and spruce (Picea abies (L.) Karst.). Ethanol extracts were formulated and applied during these experiments. Two formulations, which showed anti-fungal activity in vitro and in field trials on fruit crops (involving strawberries and raspberries) were selected for the risk assessment studies. The impact was studied of formulation treatment on crop plants and soil biological activity, and the accumulation of residues of active substances in crop plants and soil. The application of new formulations did not show any negative effect on the chlorophyll content and the chlorophyll fluorescence of plant leaves. The results showed that pine and spruce bark extract formulations contain active compounds (coumaric acid, quercetin, epicatechin, and ferulic acid) within the range of 5.1–5.9 mg kg-1 and 11.1– 443.9 mg kg-1 respectively. The amount of active substances which were determined in most cases was higher in the spruce bark extract formulation when compared to the pine bark extract formulation. Our results confirmed the presence of active compounds – epicatechin, quercetin, and coumaric acid – in strawberry fruits which remained untreated and in those that were treated with spruce ethanol extract formulation. Untreated raspberry fruits contained all four active substances within the range of 81–5,300 µg kg-1. We observed a significant increase of coumaric acid and quercetin in raspberries after their having been treated with spruce bark extract formulation in a 2% concentration, P < 0.05, and did not find any negative impact for spruce bark extract formulations when used on soil microbial biomass

Cannibalism as a life boat mechanism

Under certain conditions a cannibalistic population can survive when food for the adults is too scarce to support a non-cannibalistic population. Cannibalism can have this lifeboat effect if (i) the juveniles feed on a resource inaccessible to the adults; and (ii) the adults are cannibalistic and thus incorporate indirectly the inaccessible resource. Using a simple model we conclude that the mechanism works when, at low population densities, the average yield, in terms of new offspring, due to the energy provided by one cannibalized juvenile is larger than one

Childhood hepatitis C virus infection: An Australian national surveillance study of incident cases over five years

NHMRC: Enabling Grant No: 402784ARC Linkage Project Grant(LP110200277

Analytical solution of a model for complex food webs

We investigate numerically and analytically a recently proposed model for food webs [Nature {\bf 404}, 180 (2000)] in the limit of large web sizes and sparse interaction matrices. We obtain analytical expressions for several quantities with ecological interest, in particular the probability distributions for the number of prey and the number of predators. We find that these distributions have fast-decaying exponential and Gaussian tails, respectively. We also find that our analytical expressions are robust to changes in the details of the model.Comment: 4 pages (RevTeX). Final versio

The Thot Sign List. Recording paleographic diversity in diachrony

peer reviewedDuring the last International Congress of Egyptologists in Cairo (2019), we presented the Thot Sign List (TSL), the first digital repertoire of hieroglyphic signs (http://tsl.philo.ulg.ac.be). It quickly became an important tool for scholars and students alike, as well as for Unicode specialists who are working towards a standardized encoding of the ancient Egyptian texts (Polis et al. 2021). However, the TSL is virtually limited to the hieroglyphic signs that are attested in texts written during the classical period (c. 1900–1350 BCE) and barely covers the repertoire and paleographical variety of other periods. An extension of its scope towards earlier and later periods, as well as a geographically and palaeographically more balanced approach to the ancient Egyptian written material, is therefore a requirement if this digital repertoire is to become a proper standard and research tool for the Egyptological community. In this lecture, we discussed two evolutions of the TSL that address these issues. From a methodological point of view, we present a way to document more systematically the hieroglyphic signs that are attested in texts written both before and after the classical period (c. 3000–1900 BCE and c. 1350 BCE–150 CE), and we showcase the first results. From a technical point of view, we show how the capabilities of the tools can be extended in order to record more accurately the different types of paleographical variations across time and space.DiaTho

Effect on Fasting Serum Glucose Levels of Adding Ezetimibe to Statins in Patients With Nondiabetic Hypercholesterolemia

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