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Strongly degraded cellulosic artworks usually need deacidification and consolidation. Alkaline nanoparticles are known to be effective in neutralizing the acidity, while cellulose nanocrystals have the potential to be used as compatible and effective strengthening agents. We have grafted cellulose nanocrystals with oleic acid using a 1′1-carbonyldiimidazole-mediated procedure, to increase their dispersibility in organic solvents, and synthesized Ca(OH) 2 or CaCO 3 nanoparticles via a solvothermal process. Grafted nanocellulose and alkaline nanoparticles were used to prepare ethanol-based "hybrids". Prior to the application, the physico-chemical properties of nanocellulose dispersions and "hybrids" were studied by rheology and small-angle X-ray scattering. Cellulose nanocrystals were effectively grafted and stably dispersed in ethanol. It was shown that the use of ethanol as a dispersing medium, and the addition of alkaline nanoparticles act in a synergistic way, increasing the interactions between grafted cellulose nanocrystals, leading to the formation of clusters. These dispersions are thixotropic, a behavior particularly appealing to conservation purposes, since they can be applied in the liquid state, or, when a more confined application is required, they can be applied in a gel-like state. As a result of the application, an improvement in the mechanical properties of paper and an increase of pH were obtained. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Hypothesis The rate of stain growth of a sessile droplet deposited on paper has been previously studied (Kissa, 1981; Danino and Marmur, 1994; Kawase et al., 1986; Borhan and Rungta, 1993) but is not fully understood. In particular, the mechanism by which the abrupt decrease in growth rate occurs is unknown. This process is expected to follow a model where the disappearance of the droplet is represented by a change to the boundary condition at the droplet-paper interface when the volume of the fluid inside the paper is equal to the volume of the simulated droplet. Experiments The stain size of sessile droplets on paper was monitored against time. A series of fluids varying in surface tension and viscosity was studied. The kinetics of stain growth was modelled and compared with experiments and existing models of stain growth. Findings The measured stain area formed by a sessile droplet deposited on paper follows a two regime mechanism (Danino and Marmur, 1994). In the initial regime, the dynamics are governed by the filling of pores. However, in the later stage, the process is influenced by the emptying/redistribution of fluid. Simulations show that experimental results are well described by a model that identifies the change in boundary conditions after the droplet is no longer present above the paper, coupled with the change to a redistribution dominated mechanism. [ABSTRACT FROM AUTHOR]

Pseudoestrogene bisphenol A (BPA) can be important ingredient of thermochromic inks, increasingly used materials in thermal printing paper, security printing, advertising, design and as temperature indicators in medicine and food industry. BPA mass fraction in thermochromic inks can be up to several percent. Hence, disposal of items with thermochromic prints pose a risk of environmental pollution. In this work BPA mass fraction was monitored during anaerobic degradation of papers with thermochromic prints in soil in both matrices: papers and soil. The degradation conditions simulated deeper layers of waste at a landfill site. Six types of papers with prints of thermochromic ink containing 2% of BPA were subjected to anaerobic degradation over up to 150 days. Initial mass fractions of BPA in papers decreased form (126–460) μg/g to (

Hypotheses (1) The equilibrium size and characteristics of a radially wicked fluid on porous material such as paper is expected to be dependent on the fluid properties and therefore could serve as a diagnostic tool. (2) The change in wicked stain size between biological fluids is dependent on a change in solid-liquid surface interfacial energy due to protein adsorption. Experiments Sessile droplets of increasing volume of blood, its components, and model fluids were deposited onto paper and the equilibrium stain size after coming to a halt was recorded. The contact angle of fluid droplets on model cellulose surfaces was measured to quantify the effect that blood protein adsorption at the solid-liquid interface has on radially wicked equilibrium size. Finally the significance of droplet evaporation for the time scale of interest was analysed. Findings The final stain area of all fluids tested on paper scales remarkably linearly with droplet volume. Different fluids were compared and the gradient of this linear relation was measured. Model fluids varying in surface tension and viscosity all behave similarly and exhibit a constant gradient. Blood and its components produce smaller stains, demonstrated by lower gradients. The gradient is a function of protein concentration, thus the mechanism of this phenomenon was identified as protein adsorption at the cellulose-liquid interface. The slope of the area/volume relationship for droplets is an important quantitative mechanistic variable. [ABSTRACT FROM AUTHOR]

The rock–paper–scissors (RPS) game is known as one of the simplest cyclic dominance models. This game is key to understanding biodiversity. Three species, rock ( R ), paper ( P ) and scissors ( S ), can coexist in nature. In the present paper, we first present a metapopulation model for RPS game with mutation. Only mutation from R to S is allowed. The total population consists of spatially separated patches, and the mutation occurs in particular patches. We present reaction–diffusion equations which have two terms: reaction and migration terms. The former represents the RPS game with mutation, while the latter corresponds to random walk. The basic equations are solved analytically and numerically. It is found that the mutation induces one of three phases: the stable coexistence of three species, the stable phase of two species, and a single-species phase. The phase transitions among three phases occur by varying the mutation rate. We find the conditions for coexistence are largely changed depending on metapopulation models. We also find that the mutation induces different paradoxes in different patches. [ABSTRACT FROM AUTHOR]

Paper-based materials have attracted a great deal of attention in sensor applications because they are readily available, biodegradable, inexpensive, and mechanically flexible. Although paper-based sensors have been developed, but important obstacles remian, which include the retention of chemical and mechanical stabilities when paper is wetted. Herein, we develop a simple and scalable process for fabrication of newspaper-based platforms by coating of parylene C and patterning of metal layers. As-prepared parylene C-coated newspaper (PC-paper) provides low-cost, disposable, and mechanically and chemically stable electrochemical platforms for the development of potentiometric ion sensors for the detection of electrolyte cations, such as, H + and K + . The pH and K + sensors produced show near ideal Nernstian sensitivity, good repeatability, good ion selectivity, and low potential drift. These disposable, flexible ion sensors based on PC-paper platforms could provide new opportunities for the development of point-of-care testing sensors, for diagnostics, healthcare, and environment testing. [ABSTRACT FROM AUTHOR]

Paper is kind of essential materials in our daily life. However, it can be easily destroyed by water owing to its superhydrophilic surface. Here, we reported a simple and green fabrication of coloured superhydrophobic paper via swelling and approximate dissolution of cotton followed by precipitation of cellulose and doping coloured stearates. The obtained paper exhibited uniform colour and superhydrophobicity, of which the colour was consistent with the doped stearates owing to the adhesion of stearate powders to the tiny floc fiber surface and we proved that the superhydrophobicity could not be damaged after abrasion resulting from the inner and outer superhydrophobicity and the increased surface roughness. This coloured superhydrophobic paper would be avoided from moisture damage and may be useful in different fields. [ABSTRACT FROM AUTHOR]

Chymotrypsin (CHT) is an important proteolytic enzyme that can quickly decompose denatured proteins. Herein, we reported a new, simple, rapid method for the detection of CHT and its inhibitors by a paper-based flow sensor for the first time. The principle of the sensor is the interconversion of solidification and dissolution of gelatin. Generally, the 3D structure of gelatin can be enzymatically hydrolyzed by CHT releasing internal water, leading to a gradual increase in the water mark coverage area. Conversely, water cannot be released and the water mark coverage area is 0 in the absence of CHT, which is attributed to the water being trapped in the gelatin hydrogel. The limit of detection of CHT is determined to be 0.8 U/mL. In addition, the detection of CHT in milk, screening of CHT inhibitors and determination of Bowman-Birk inhibitors in soymilk were successfully achieved. Interestingly, the sensor only requires gelatin hydrogel, pH indicator strips, and PVC plates. In summary, a rapid, high-throughput, low-cost strategy for the detection of CHT and screening of CHT inhibitors was developed. Moreover, this method also allows the detection of CHT in non-transparent samples such as milk and soymilk. Paper-based flow sensors are highly promising for applications in food quality control, new medicine discovery and disease diagnosis, which also have a high potential for commercialization. [Display omitted] • Gelatin hydrogel can be enzymatically hydrolyzed by chymotrypsin. • Paper-based flow sensor can detect the concentration of chymotrypsin in milk. • The sensor can determine the content of Bowman-Birk inhibitor in soymilk. • The screening of functional compounds from foods can be finished by the sensor. • The sensor only requires gelatin hydrogel, pH indicator strips and PVC substrates. [ABSTRACT FROM AUTHOR]

Mold deterioration of historical documents in archives and libraries is a frequent and complex phenomenon that may have important economic and cultural consequences. In addition, exposure to toxic fungal metabolites might produce health problems. In this work, samples of broths of fungal species isolated from the documentary material and from indoor environmental samples of the Archive of Bogotá have been analyzed to investigate the presence of mycotoxins. High resolution mass spectrometry made possible to search for a large number of mycotoxins, even without reference standards available at the laboratory. For this purpose, a screening strategy based on ultra-high pressure liquid chromatography coupled to quadrupole-time of flight mass spectrometry (UHPLC–QTOF MS) under MS E mode was applied. A customized home-made database containing elemental composition for around 600 mycotoxins was compiled. The presence of the (de)protonated molecule measured at its accurate mass was evaluated in the samples. When a peak was detected, collision induced dissociation fragments and characteristic isotopic ions were also evaluated and used for tentative identification, based on structure compatibility and comparison with literature data (if existing). Up to 44 mycotoxins were tentatively identified by UHPLC–QTOF MS. 34 of these tentative compounds were confirmed by subsequent analysis using a targeted LC–MS/MS method, supporting the strong potential of QTOF MS for identification/elucidation purposes. The presence of mycotoxins in these samples might help to reinforce safety measures for researchers and staff who work on reception, restoration and conservation of archival material, not only at the Archive of Bogotá but worldwide. [ABSTRACT FROM AUTHOR]

Alternatives to bisphenol A (BPA) are more and more used in thermal paper receipts. To get an overview of the situation in Switzerland, 124 thermal paper receipts were collected and analyzed. Whereas BPA was detected in most samples ( n = 100), some alternatives, namely bisphenol S (BPS), Pergafast® 201 and D-8 have been found in 4, 11 and 9 samples respectively. As no or few data on their endocrine activity are available, these chemicals and bisphenol F (BPF) were tested in vitro using the H295R steroidogenesis assay. 17β-Estradiol production was induced by BPA and BPF, whereas free testosterone production was inhibited by BPA and BPS. Both non-bisphenol substances did not show significant effects. The binding affinity to 16 proteins and the toxicological potential (TP) were further calculated in silico using VirtualToxLab™. TP values lay between 0.269 and 0.476 and the main target was the estrogen receptor β (84.4 nM to 1.33 μM). A substitution of BPA by BPF and BPS should be thus considered with caution, since they exhibit almost a similar endocrine activity as BPA. D-8 and Pergafast® 201 could be alternatives to replace BPA, however further analyses are needed to better characterize their effects on the hormonal system. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Lucas–Washburn equation is inadequate in predicting water intake at short contact times. [•] The Lucas–Washburn equation inadequate for predicting intake as a function of temperature. [•] The absorption rate increase with temperature is controlled by molecular processes. [•] The adsorbed water on fiber surfaces lowers the solid–gas interfacial energy. [ABSTRACT FROM AUTHOR]

Highlights: [•] AuNPs on paper were functionalized to develop SERS biodiagnostic platform. [•] Reproducible SERS spectra of antibody–antigen were achieved. [•] Modification of antibody structure upon antigen binding resulted in Raman shifts. [•] SERS intensity increased as a function of antigen concentration. [ABSTRACT FROM AUTHOR]

The amount of compostable bioplastics collected with the food waste is constantly growing, particularly due to the bags used for collection. According to the Italian legislation, compostable bioplastics must be accepted by all biological treatment plants, including aerobic and anaerobic facilities. Anyway, the compostability standard requires only the assessment of the aerobic degradability, while it is generally not required to test the behaviour under anaerobic conditions. This aspect is evaluated in the paper, where the anaerobic degradability of bioplastic bags used for the food waste collection is assessed. First, Biochemical Methane Potential (BMP) tests were performed on four commercial types of bioplastic bags, including those designed only for the collection of food waste and the shoppers, that can be reused for the same purpose. Subsequently, an innovative approach for this kind of substrate was applied, subjecting two bags to semi-continuous co-digestion tests together with the food waste. Both tests were performed by comparing the behaviour of bioplastic bags with that of an alternative collection paper bag. Finally, tests to evaluate the influence of physical phenomena on the degradation of bioplastics were performed to better understand the results of biological tests. BMP tests indicated a good degradability (>71%) of bioplastic bags, while semi-continuous tests showed a much lower degradability (<27%), confirmed by the observation of the undigested bag pieces. On the contrary, the paper bag presents interesting characteristics, because its degradability in the semi-continuous tests (82%) resulted even higher than that observed in the BMP tests (74%). These results highlight an important difference between the bags mono-digestion by means of BMP tests and the semi-continuous co-digestion tests with food waste, which better simulate the full-scale operational conditions. [Display omitted] • Bioplastic and paper bags were tested with BMP and semi-continuous digestion tests. • Paper bags show a good degradability in both the tests (>74%). • The BMP tests on bioplastic bags indicate a good degradability (>71%). • Semi-continuous digestion of bioplastics with food waste shows a low degradability. • The degradability of bioplastics is influenced by physical factors. [ABSTRACT FROM AUTHOR]

Highlights: [•] Gold nanoparticle–polyelectrolyte necklace structures were formed on paper. [•] The effect of polymer properties on necklace characteristics was quantified. [•] Optimized conditions and mechanism were proposed. [ABSTRACT FROM AUTHOR]

Abstract: This study examines and quantifies the effect of cationic polyelectrolyte adsorption on paper on the aggregation and retention of gold nanoparticles (AuNPs) to optimize their Surface Enhanced Raman Scattering (SERS) enhancement factor and sensitivity. Aggregation of metallic nanoparticles is known as a key factor for intense SERS enhancement. Paper substrates were treated with aqueous solutions of cationic polyacrylamide (CPAM) varying in concentration, charge density, and molecular weight to control the AuNPs’ aggregate size distribution and surface coverage on paper. The Raman Enhancement Factor of AuNPs-CPAM paper was almost an order of magnitude greater than for the untreated AuNPs paper. The high loading and uniform distribution of AuNPs aggregates on CPAM pre-treated paper contributed toward the excellent SERS reproducibility, sensitivity, and high enhancement factor. This configuration of AuNP on paper was favoured by treating the substrate with CPAM solutions of higher concentrations, higher charge density, and greater molecular weight. [Copyright &y& Elsevier]

Abstract: This paper estimates the effects of humidity and temperature on mortality rates in the United States (c. 1973–2002) in order to provide an insight into the potential health impacts of climate change. I find that humidity, like temperature, is an important determinant of mortality. Coupled with Hadley CM3 climate-change predictions, I project that mortality rates are likely to change little on the aggregate for the United States. However, distributional impacts matter: mortality rates are likely to decline in cold and dry areas, but increase in hot and humid areas. Further, accounting for humidity has important implications for evaluating these distributional effects. [Copyright &y& Elsevier]

Abstract: The surface chemical and physical character of offset paper was studied before and after application of model fountain solutions based on isopropyl alcohol and an alcohol-free surfactant solution. The paper surface features were characterised with atomic force microscopy and the surface energies were determined by contact angle measurements. Changes in the surface chemical properties induced by the fountain solutions were investigated with X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectroscopy. Coated papers wetted with the surfactant solution revealed a slight increase in the root mean square roughness, but the isopropyl alcohol solution led to no observable changes. The change in sub-micro roughness is ascribed not only to substrate swelling or migration of coating constituents but also to the presence of surfactant on the surface. A change in the surface energy and particularly the polar contribution was observed after application of the surfactant solution. The X-ray photoelectron spectroscopy showed an increase in the oxygen-to-carbon ratio, which confirms the presence of surfactant on the surface. Time-of-flight secondary ion mass spectroscopy showed that the isopropyl alcohol solution did not change the elemental composition of the surface whereas the surfactant solution clearly did so. The distribution of surfactant on the surface was confirmed by mapping the characteristic fragments of the molecule. [Copyright &y& Elsevier]

Abstract: The treatment of additive-free hand sheet paper samples with cold plasma was carried out and showed that cellulose can be chemically linked with reactive natural products, namely myrcene (My) and limonene (LM). Contact-angle measurement and X-ray photoelectron spectroscopy (XPS) were used to ascertain the occurrence of the grafting. Indeed, the contact-angle value of a drop of water deposited at the surface of paper increased from 30° for unmodified substrate to about 105 and 107°, for LM- and My-treated samples, respectively. In fact, LM- and My-treated surfaces were rendered totally apolar. Indeed, the polar contribution to the surface energy decreased from about 23 mJ/m2 for pristine samples to practically zero for treated ones. The treated surfaces displayed water-barrier properties; the penetration of the liquid was reduced significantly after LM and My treatments. The XPS spectra showed that the modification with LM and My gave rise to very significant change in the O/C ratio, as well as in the intensity of the C1 peak assigned to aliphatic carbon sequences. [Copyright &y& Elsevier]

Abstract: This paper compares the influence of the molecular weight of polylelectrolytes forming polyelectrolyte multilayers (PEM) on wood fibers on adhesion and paper strength. Sheets were made from fibers treated with poly(allylamine hydrochloride) (PAH)/poly(acrylic acid) (PAA) of molecular mass 70,000 and 240,000, respectively, and of poly(dimethyldiallylammonium chloride) (PDADMAC)/poly(styrene sulfonate) (PSS) of molecular mass 30,000 and 80,000, respectively. The results were compared to what has recently been reported for PEM formation on fibers using a low-molecular-mass combination of PAH and PAA and a high-molecular-mass combination of PDADMAC/PSS. There was a less significant improvement in the case of the low-molecular-mass PDADMAC/PSS and the high-molecular-mass PAH/PAA. The adsorbed amounts of PAH and PDADMAC were also determined, showing a lower adsorbed amount of the low-molecular-mass PAH than of the high-molecular-mass PDADMAC. The amount of low-molecular-mass PDADMAC was similar to that found for high-molecular-mass PDADMAC/PSS. Individual fibers were partly treated and studied, showing a less significant decrease in wettability with low-molecular-mass PDADMAC/PSS than with the high-molecular-mass combination. The effect of the molecular weight on the adhesion was discussed in terms of the structure and wettability of the PEMs. [Copyright &y& Elsevier]

Abstract: The immersed boundary method has evolved into one of the most useful computational methods in studying fluid structure interaction. On the other hand, the immersed boundary method is also known to suffer from a severe timestep stability restriction when using an explicit time discretization. In this paper, we propose several efficient semi-implicit schemes to remove this stiffness from the immersed boundary method for the two-dimensional Stokes flow. First, we obtain a novel unconditionally stable semi-implicit discretization for the immersed boundary problem. Using this unconditionally stable discretization as a building block, we derive several efficient semi-implicit schemes for the immersed boundary problem by applying the small scale decomposition to this unconditionally stable discretization. Our stability analysis and extensive numerical experiments show that our semi-implicit schemes offer much better stability property than the explicit scheme. Unlike other implicit or semi-implicit schemes proposed in the literature, our semi-implicit schemes can be solved explicitly in the spectral space. Thus the computational cost of our semi-implicit schemes is comparable to that of an explicit scheme, but with a much better stability property. [Copyright &y& Elsevier]

Abstract: The paper proves a pumping lemma for a certain subclass of mildly context-sensitive languages, the one defined by commutation-augmented pregroup grammars; in addition, an automaton equivalent to such grammars is introduced, augmenting push-down automata by cancellation in the bottom of its stack. [Copyright &y& Elsevier]

Abstract: This paper presents an experimental study of a mechanism that is commonly used to sell multiple heterogeneous goods. The novel feature of this procedure is that instead of selling each good in a separate auction, the seller executes a single auction in which buyers, who may be interested in completely different goods, compete for the right to choose a good. We provide experimental evidence that a Right-to-Choose (RTC) auction can generate more revenue than the theoretically optimal auction. Moreover, in contrast to the “optimal” auction, the RTC auction is approximately efficient in the sense that the surplus it generates is close to the maximal one. Furthermore, a seller who would like to retain some of his goods can generate more revenue with a restricted RTC auction in which not all rights-to-choose are sold, than with the theoretically optimal auction. [Copyright &y& Elsevier]

Abstract: There are two main results in the paper. In the first one, Theorem 1, we prove that if the Sobolev embedding theorem holds in Ω, in any of all the possible cases, then Ω satisfies the measure density condition. The second main result, Theorem 5, provides several characterizations of the -extension domains for . As a corollary we prove that the property of being a -extension domain, , is invariant under bi-Lipschitz mappings, Theorem 8. [Copyright &y& Elsevier]

Abstract: Individual wood fibres were partly treated with polyelectrolyte multilayers (PEMs) consisting of two different polymer combinations, poly allylamine (PAH)/poly acrylic acid (PAA) and polyethylene oxide (PEO)/PAA in order to study the influence of these polymers on fibre wettability. Single fibres were partly treated and analysed using a so-called dynamic contact analyser (DCA) where the fibres are wet under controlled conditions. When PAH/PAA was used, a stronger influence on fibre wettability was detected when PAH was adsorbed in the outermost layer of the multilayer than when PAA was adsorbed in the outermost layer. The wettability of fibres treated with PAH/PAA PEMs was also influenced by the pH of the adsorption. With the PEO/PAA system, however, the type of polymer adsorbed in the outermost layer caused no detectable difference. Tests of sheets prepared from fibres treated with PEO/PAA showed an increase of about 90% in the tensile index when 9 layers were adsorbed. These and other recently published results from similar experiments using PAH/PAA [S.M. Notley, M. Eriksson, L. Wågberg, J. Colloid Interface Sci. 292 (2005) 29] are compared to the results for the PEM-treated individual fibres. The results indicate that fibres with low wettability contribute to greater paper strength. AFM-force measurements, with the aid of a colloidal probe technique, have also been performed using PAH/PAA, showing that there is also a close correlation between lower wettability of the surfaces and a higher pull-off force between the PEM treated surfaces, i.e. the flat surface and the colloidal probe. This is valid for the two pH strategies that are used for the formation for the PAH/PAA PEMs, which are studied using AFM-force measurements. [Copyright &y& Elsevier]

Abstract: This is the final paper in a series of four on fixed point ratios in non-subspace actions of finite classical groups. Our main result states that if G is a finite almost simple classical group and Ω is a faithful transitive non-subspace G-set then either for all elements of prime order, or is one of a small number of known exceptions. In this paper we assume is either an almost simple irreducible subgroup in Aschbacher''s collection, or a subgroup in a small additional set which arises when G has socle (q even) or . This completes the proof of the main theorem. [Copyright &y& Elsevier]

Abstract: In this paper, we give some characterizations of the integral and Carleson type measure both associated with higher radial derivative for holomorphic functions of and spaces in the unit ball of . As applications, some sharp forms of the relations between Dirichlet type spaces and spaces are shown by means of higher radial derivative, Carleson type measure and constructive methods for the cases of determinism and randomization, respectively. [Copyright &y& Elsevier]

Abstract: This paper studies the characteristics and structure of the weak surface of the production possibility set. We apply techniques and methods of transferring a polyhedral cone from its intersection form to its sum form, identify an intersection representation of the production possibility set. We give the structure theorem of weak surface of the production possibility set, which includes three complementary slackness conditions. We define the input weak efficiency and output weak efficiency for different DEA models according to the representation of the intersection form. It investigates the characteristics of the weak surfaces, and proves the structure theorems of input weak DEA efficiency and output weak DEA efficiency. The structure theorems establish weighted combination of inputs and outputs that are weak DEA efficient. Numerical examples are provided for illustration. [Copyright &y& Elsevier]

Abstract: The purpose of this paper is to show that various classes of operators having a common collection of root spaces whose closed linear span equals the entire space have dense sets of common cyclic vectors. [Copyright &y& Elsevier]

Abstract: In this paper, we study a boundary feedback system of a class of nonuniform undamped Timoshenko beam with both ends free. We give some sufficient conditions and some necessary conditions for the system to have exponential stability. Our method is based on the operator semigroup technique, the multiplier technique, and the contradiction argument of the frequency domain method. [Copyright &y& Elsevier]

Abstract: This paper deals with a parabolic system, cross-coupled via a nonlinear source and a nonlinear boundary flux. We get a necessary and sufficient condition for the existence of non-simultaneous blow-up. In particular, four different simultaneous blow-up rates are obtained in different regions of parameters, described by an introduced characteristic algebraic system. It is observed that different initial data may result in different simultaneous blow-up rates even in the same region of parameters. [Copyright &y& Elsevier]

Abstract: Polydimethyldiallylammonium chloride (PDADMAC) and polystyrene sulfonate (PSS) have been used to build-up polyelectrolyte multilayers (PEMs) on chemical soft wood fibres and on SiO2 at various electrolyte concentrations. Adsorption onto SiO2 was studied using a stagnation point adsorption reflectometer (SPAR), and the adsorbed amount of PDADMAC and PSS on the fibres was determined using nitrogen analysis and Schöniger burning, respectively. The adsorption onto the two substrates was then compared. Paper testing showed that the tensile index (TI) increased by about 90% when 11 layers had been adsorbed, and that there was a correlation between the adsorbed amount and the increase in TI. It was also shown that the particular polymer present in the outermost layer significantly influenced the TI, and that PDADMAC produced a higher TI. A correlation between the adsorbed amount and the TI was also found. Individual fibres were partly treated with a PEM and analysed using a dynamic contact angle analyser (DCA) and environmental scanning electron microscopy (ESEM). [Copyright &y& Elsevier]

Abstract: In this paper, we study the dynamics of predator–prey interaction systems between two species with ratio-dependent functional responses. First we provide sufficient and necessary conditions for positive steady-state solutions, and then we investigate the relationships between positive equilibria and positive solutions of the system over a large domain. Furthermore, we deal with the uniqueness and the stability of positive steady-states solutions with some assumptions. In addition, we discuss the extinction and the persistence results of time-dependent positive solutions to the system. [Copyright &y& Elsevier]

Abstract: In this paper, a novel approach to the impulsive noise removal in color images is presented. The proposed technique employs the switching scheme based on the impulse detection mechanism using the so-called peer group concept. Compared to the vector median filter and other commonly used multichannel filters, the proposed technique consistently yields very good results in suppressing both the random and fixed-valued impulsive noise. The main advantage of the proposed noise detection framework is its enormous computational speed, which enables efficient filtering of color images in real-time applications. [Copyright &y& Elsevier]

Abstract: The present paper explores the notion that an important difference between prior operational definitions of “cue” or “heuristic” information versus “message argument” information has to do with differential processing difficulty, and relative ordinal position of these two information types. In previous work, “cue/heuristic” information typically differed from “message argument” information not only in its contents, but also in it being (1) briefer, and (2) presented prior to the message information. We find that it is relative brevity and ordinal position rather than contents that ultimately explain the differences in persuasive impact between “cue/heuristic” versus “message argument” information. In so far as both “cues” and “message arguments” can vary in brevity and order with which they are presented, these findings are consistent with the view that these two information types do not necessarily differ in their persuasive impact. [Copyright &y& Elsevier]

Abstract: This paper discusses the relationship between environmental and economic performance and the influence of corporate strategies with regard to sustainability and the environment. After formulating a theoretical model, results are reported from an empirical analysis of the European paper manufacturing industry. New data are used to test hypotheses derived from the theoretical model, using environmental performance indices representing different corporate environmental strategy orientations. In particular, an emissions-based index largely reflecting end-of-pipe strategies and an inputs-based index reflecting integrated pollution prevention are distinguished. For the emissions-based index, a predominantly negative relationship between environmental and economic performance is found, whereas for the inputs-based index no significant link is found. This is consistent with the theoretical model, which predicts the possibility of different relationships. The results also show that for firms with pollution prevention-oriented corporate environmental strategies, the relationship between environmental and economic performance is more positive, thus making improvements in corporate sustainability more likely. Based on this last insight, managerial implications of this are discussed with regard to strategy choices, investment decisions and operations management. [Copyright &y& Elsevier]

A watermark hidden in an image is retrieved differently from the original watermark due to the frequently used rounding approach. The simple rounding will cause numerous errors in the embedded watermark especially when it is large. A novel technique based on genetic algorithms (GAs) is presented in this paper to correct the rounding errors. The fundamental is to adopt a fitness function for choosing the best chromosome which determines the conversion rule of real numbers into integers during the cosine transformation. Experimental results show that the dramatic improvement in reducing the errors is successful when GAs are used in decision making. Furthermore, we develop an initial chromosome by comparing the difference between the original image and the rounded watermarked image to speed up the process. In additional to correct fragile-watermarking rounding errors, our algorithm can also be applied in robust watermarking to achieve higher watermarked image quality. [ABSTRACT FROM AUTHOR]

Abstract: A void network model, named Pore-Cor, has been used to study the permeation of an ink solvent into paper coating formulations coated onto a synthetic substrate. The network model generated anisotropic void networks of rectangular cross-sectional pores connected by elliptical cross-sectional throats. These structures had porosities and mercury intrusion properties which closely matched those of the experimental samples. The permeation of hexadecane, used as an analogue for the experimental test oil, was then simulated through these void structures. The simulations were compared to measurements of the permeation of mineral oil into four types of paper coating formulation. The simulations showed that the inertia of the fluid as it enters void features causes a considerable change in wetting over a few milliseconds, a timescale relevant to printing in a modern press. They also showed that in the more anisotropic samples, fast advance wetting occurred through narrow void features. It was found that the match between experimental and simulated wetting could be improved by correcting the simulation for the number of surface throats. The simulations showed a more realistic experimental trend, and much greater preferential flow, than the traditional Lucas–Washburn and effective hydraulic radius approaches. [Copyright &y& Elsevier]

Abstract: This paper presents a detailed description of a real-time correlation-based stereo algorithm running completely on the graphics processing unit (GPU). This is important since it allows to free up the main processor for other tasks including high-level interpretation of the stereo results. We first introduce a two-view stereo algorithm that includes some advanced features such as adaptive windows and cross-checking. Then we extend it using a plane-sweep approach to allow multiple frames without rectification. By taking advantage of advanced features of recent GPUs the proposed algorithm runs in real-time. Our implementation running on an ATI Radeon 9800 graphics card achieves up to 289 million disparity evaluations per second including all the overhead to download images and read-back the disparity map, which is several times faster than commercially available CPU-based implementations. [Copyright &y& Elsevier]

In this paper, we show that two Zariski dense subgroups consisting of hyperbolic elements in SO(n+1,n)⋉R2n+1 with the same marked Margulis invariant, are conjugate. We also consider in affine deformations an analogue of quasifuchsian deformation of Fuchsian groups. [Copyright &y& Elsevier]

In this paper we deal with movement-independent individual muscle properties derived from Hill''s equation. Relations between these properties are found by theoretical considerations. We define a dimensionless quantity that turns out to play a major role in characterizing individual muscle properties, and we analyse normalization and symmetry behaviour of the parameters in Hill''s equation. This leads to a systematic, transparent, and useful overview of mathematical relations involving muscle parameters. We examine the experimentally determined parameters of 62 subjects to find additional empirical relations between the muscle properties described by the parameters of Hill''s equation. In the light of the theoretical end empirical results we investigate the connections between maximum efficiency, endurance, and fibre composition. [Copyright &y& Elsevier]

Abstract: In a previous paper, the author introduced a new class of multivariate rational interpolants, which are called Optimal Padé-type Approximants (OPTA). There, for this class of rational interpolants, which extends classical univariate Padé Approximants, a direct extension of the “de Montessus de Ballore''s Theorem” for meromorphic functions in several variables is established. In the univariate case, this theorem ensures uniform convergence of a row of Pade Approximants when the denominator degree equals the number of poles (counting multiplicities) in a certain disc. When one overshoots the number of poles when fixing the denominator degree, convergence in measure or capacity has been proved and, under certain additional restrictions, the uniform convergence of a subsequence of the row. The author tackles the latter case and studies its generalization to functions in several variables by using OPTA. [Copyright &y& Elsevier]

The use of a portable NMR device allows a non-invasive investigation of the paper in order to assess the state of conservation of books and documents of historical or artistic interest. The NMR investigation has been found mainly on relaxation measurements whose results seem compatible with different relaxation rates in crystalline and amorphous cellulose domains. By a simplified physical picture based on spin–diffusion it appears possible to detect the alteration of the crystalline/amorphous cellulose balance and therefore to get information on some deterioration processes of paper. The use of a portable NMR device shows great potentiality because of its safe and simple in situ approach to Cultural Heritage documents. In this work, we present a research carried out on a 17th century manuscript. [Copyright &y& Elsevier]

In this paper we investigate the following question: if NP is slightly hard on average, is it very hard on average? We give a positive answer: if there is a function in NP which is infinitely often balanced and (1-1/poly(n))-hard for circuits of polynomial size, then there is a function in NP which is infinitely often (1/2+n-1/2+#x03B5;)-hard for circuits of polynomial size. Our proof technique is to generalize the Yao XOR Lemma, allowing us to characterize nearly tightly the hardness of a composite function g( f(x1),…,f(xn)) in terms of: (i) the original hardness of f, and (ii) the expected bias of the function g when subjected to random restrictions. The computational result we prove essentially matches an information-theoretic bound. [Copyright &y& Elsevier]

The nonlinear dynamics of the impact and penetration of a liquid droplet in a radial capillary is studied numerically. The radial capillary is formed by two parallel plates at a distance of δg. The top plate has an orifice at its center. A droplet impacting on the orifice-plate partly spreads over the top plate, and the rest penetrates into the capillary gap between the two plates. The rate of spread of the fluid on the orifice plate, ξout, is governed by the contact angle, β, between the liquid and the orifice plate and the droplet initial momentum, whereas the rate of fluid spread inside the capillary gap, ξin, is decided by the contact angles with both plates and the plate gap, δg. [Copyright &y& Elsevier]

Paper–TiO 2 –Ag 2 O floating photocatalysts were produced under mild condition and their photocatalytic activity for the degradation of aromatic amine under sunlight stimulant was investigated. Characterizations by Raman, XRD, XPS, DRS and PL confirmed the presence of TiO 2 and Ag 2 O, and the morphology of the appended TiO 2 /Ag 2 O layer was probed by FE-SEM. The photocatalytic activity of the prepared samples was investigated by the degradation of aniline (AN) in water under simulated sun-light illumination and constrained conditions, i.e. non-stirring and non-oxygenation. The presence of Ag 2 O combined with TiO 2 was shown to improve the resistance of paper to bacteria attack, thus increasing the durability of the photocatalyst. Thanks to its hydrophobic character, the paper–TiO 2 –Ag 2 O NPs can be employed as useful floating photocatalyst and can be reused in continuous cycles. • Paper–TiO 2 decorated with Ag 2 O nanoparticles was prepared by a facile method. •Generation of TiO 2 anatase and Ag 2 O phases was confirmed by XRD, Raman and XPS. •Paper–TiO 2 –Ag 2 O exhibits excellent photodegradation activity toward of aniline. •Paper–TiO 2 –Ag 2 O displays good antibacterial activity against E. Coli under sunlight. [ABSTRACT FROM AUTHOR]