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Abstract: Beyond the linear model of Schulze et al. [J. Adhes. Sci. Technol. 3 (1) (1989) 39–48], a more comprehensive model for predicting the Young contact angle of rough and chemically homogeneous surfaces from contact angle hysteresis measurements is proposed. This new model incorporates the barrier effect, described by Shuttleworth and Bailey, and the Wenzel model as well. Both the linear and nonlinear models were evaluated using a thermoplastic polyether-based elastomer and PDMS and two liquids. The elastomer surfaces were textured on purpose at differing degrees of roughness. Both models provided similar values of Young angle, although the nonlinear model also provided information about the distribution of practical metastable configurations around the most stable equilibrium configuration. Despite the linear model showed slightly better goodness-of-fit and minor uncertainties in its parameters, the nonlinear model is more reliable and theoretically consistent. [Copyright &y& Elsevier]

Abstract: The present work has analysed the gas–liquid mass transfer process of carbon dioxide to aqueous solutions polluted with the presence of different surface active substances. The influence of the hydrocarbonate chain length of surfactant employed upon the value of mass transfer coefficient has been analysed. The influences of surfactant nature, solutes concentration and the gas flow-rate fed to the bubble column contactor have been studied in the present work. Different models have been employed to fit experimental values of mass transfer coefficient. [Copyright &y& Elsevier]

Abstract: Proposals for wind farms in areas of known importance for breeding seabirds highlight the need to understand the impacts of these structures. Using an energetic modelling approach, we examine the effects of wind farms as barriers to movement on seabirds of differing morphology. Additional costs, expressed in relation to typical daily energetic expenditures, were highest per unit flight for seabirds with high wing loadings, such as cormorants. Taking species-specific differences into account, costs were relatively higher in terns, due to the high daily frequency of foraging flights. For all species, costs of extra flight to avoid a wind farm appear much less than those imposed by low food abundance or adverse weather, although such costs will be additive to these. We conclude that adopting a species-specific approach is essential when assessing the impacts of wind farms on breeding seabird populations, to fully anticipate the effects of avoidance flights. [Copyright &y& Elsevier]

The Danube River has always been a natural barrier as well as a navigable channel - these two major aspects being crucial for the economic development of its common border states for a long period of time. In the context of economic globalization, the barrier effect of the Danube tends to lose importance, becoming a major issue in regional development. The problems raised by the Danube in the territorial policies of development have a direct influence on the regional development of the South- West Oltenia Region. This represents one of the strongest issues for the future strategies of development. The Danube River must be contextualized again and transformed from a nonpermissive barrier into a permissive one. [ABSTRACT FROM AUTHOR]

Abstract: The “fragmentation–barrier” effect of road network expansion on landscape function draws attention throughout the world. Presently, there is a lack of quantitative analysis to integrate different ecological effects of road networks at landscape scale to depict, compare and evaluate landscape changes. In this study, the “Probability of Connectivity (PC)” index was used to evaluate the effects of road networks on landscape connectivity for an area in Xishuangbanna, Southwest China. The results indicate that the fragmentation effect of road networks decreased in PC value by 15.81%, the barrier effect of road networks decreased in PC value by 11.73% and the combination of the two effects decreased PC value by 32.78%. In conclusion, the combined fragmentation and barrier effects of road networks considerably degraded landscape connectivity more than either individual effect. In addition, the fragmentation effect influenced connectivity to a greater degree for ecological processes having low movement abilities. The barrier effect influenced connectivity to a greater degree for medium to high movement abilities. The combined effects influenced connectivity for those ecological processes of low movement ability within the study area. [Copyright &y& Elsevier]

Abstract: The tidal regime modeling system for ocean tides in the seas bordering the Korean Peninsula is designed to cover an area that is broad in scope and size, yet provide a high degree of resolution in coastal development areas, including the Saemangeum area in the eastern Yellow Sea and the Ariake Sea in Japan, where serious environmental problems have occurred after the completion of interior tidal dikes. With this simulation system, we have estimated the changes in tidal regime due to barriers at Saemangeum and Isahaya Bay in the Ariake Sea. Some results in terms of perturbations in tidal elevations due to the construction of coastal dikes are presented and discussed. [Copyright &y& Elsevier]

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Roads and traffic are pervasive components of landscapes throughout the world: they cause wildlife mortality, disrupt animal movements, and increase the risk of extinction. Expensive engineering solutions, such as overpasses and tunnels, are increasingly being adopted to mitigate these effects. Although some species readily use such structures, their success in preventing population extinction remains unknown. Here, we use population viability modeling to assess the effectiveness of tunnels for the endangered Mountain Pygmy-possum (Burramys parvus) in Australia. The underpasses reduced, but did not completely remove, the negative effects of a road. The expected minimum population size of a "reconnected" population remained 15% lower than that of a comparable "undivided" population. We propose that the extent to which the risk of extinction decreases should be adopted as a measure of effectiveness of mitigation measures and that the use of population modeling become routine in these evaluations. [ABSTRACT FROM AUTHOR]

Recently, polymer/polymer composite insulating systems have been widely used in high-voltage equipment and power cables. Such composite insulating systems always have an interface between two polymeric insulating materials. This interface may cause partial discharge and electrical treeing under high electric stresses. The electrical properties of this polymer/polymer interface have not yet been fully understood. It has been shown that the propagation characteristics of electrical trees in polymer/polymer composite insulating materials considerably vary depending on the combination of polymers. It has also been shown that a cavity or a thin gas layer generates near the polymer barrier molded in the base polymer, by the pressure of decomposing gas occurring in the tree channels during AC tree extension. In this study, we will investigate the three-dimensional simulated tree utilizing a three-layer model considering a thin gas layer on a barrier based on a DBM model with growth probability. The results show that the critical fields of air layer are related to the easiness of tree propagation in the air layer. Moreover, it is suggested that the three-layer model is more effective than the two-layer model when the tree propagation is discussed in detail. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(3): 1–9, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20808 [ABSTRACT FROM AUTHOR]

Masden, E. A., Haydon, D. T., Fox, A. D., Furness, R. W., Bullman, R., and Desholm, M. 2009. Barriers to movement: impacts of wind farms on migrating birds. – ICES Journal of Marine Science, 66: 746–753. Advances in technology and engineering are enhancing the contribution that wind power makes to renewable energy generation. Wind farms, both operational and in planning, can be expected to impact negatively on wildlife populations, particularly birds. We propose a novel approach to assess the impacts through the energetic costs of avoidance behaviour for a long-distance, migratory seaduck. Flight trajectories were recorded using surveillance radar at a Danish offshore wind farm with emphasis placed on the 200 000+ migrating common eiders that pass through the area annually. Minimum distance to wind farm and curvature of trajectories were compared pre- and post-construction. Additional costs of the avoidance response were estimated using an avian energetic model. The curvature of eider trajectories was greatest post-construction and within 500 m of the wind farm, with a median curvature significantly greater than pre-construction, suggesting that the birds adjusted their flight paths in the presence of the wind farm. Additional distance travelled as a consequence of the wind farm's presence was ca. 500 m and trivial compared with the total costs of a migration episode of 1400 km. However, construction of further wind farms along the migration route could have cumulative effects on the population, especially when considered in combination with other human actions. [ABSTRACT FROM PUBLISHER]

This paper proposes an elastic solution for evaluating tunneling-induced vertical ground displacements due to the restraint of embedded isolation piles. Based on the modified Loganathan-Poulos (L&P) formula and the general form of the Melan/Mindlin solution, the restrained tunneling-induced vertical ground displacements can be calculated according to the displacement compatibility condition at the pile-soil interface. The solution can consider the relative vertical slip between the pile shaft and the surrounding soil and the embedding of the pile tip into the supported soil. The method is verified through comparisons with existing analytical solutions, boundary element program and field-measured data. Parametric analysis indicates that the parameters associated with the isolation pile (the distance of the tunnel axis from the pile axis, the pile length and the relative pile axis stiffness) and the soil (Poisson's ratio, the friction angle and the ground volume loss) have important influences on the ground surface settlement troughs and the barrier efficiency. The results also show that the pile skin-soil shear stiffness, which characterizes the relative slip between the pile shaft and the surrounding soil, determines the barrier efficiency. When the pile-soil interface is completely bonded, the contact state of the pile tip with the supported soil also has a nonnegligible impact on the barrier efficiency. [ABSTRACT FROM AUTHOR]

Landscape effects might impede or increase spore dispersal and disease risk for crops, as trees and hedges buffer winds and can behave as spore traps, therefore limiting diffusion of fungi, or, on the contrary, behave as disease relay once vegetation is infected and become inoculum sources. In this study, we investigated weekly prevalence of the pathogenic fungus Colletotrichum gloeosporioides on guava tree leaves, differentiating impacts of leaf height on tree, age, and location within leaf. We first estimated differences in prevalence for each covariate, and then related infection rates to weather effects during the year. Our results highlighted a great variance of prevalence among individual trees, and a lower contamination of tree tops, as well as a tendency for greater odds of infection in tips of young leaves compared to older ones. Last, we show evidence that individual tree contaminations are associated with different disease dynamics: early and dispersal-based, late and growth-based, as well as with intermediate dynamic ranges. Pathogen infection dynamics will thus be greatly impacted by cover characteristics at local scale, and tree cover should not be perceived as homogeneously driving disease levels. [ABSTRACT FROM AUTHOR]

A new multigrid method based on high-order vector finite elements is proposed in this paper. Low-level discretizations in this method are obtained by using low-order vector finite elements for the same mesh. The Gauss–Seidel method is used as a smoother, and a linear equation of lowest level is solved by the ICCG method. But it is often found that multigrid solutions do not converge into ICCG solutions. An elimination algorithm of constant term using a null space of the coefficient matrix is also described. In three-dimensional magnetostatic field analysis, convergence time and number of iteration of this multigrid method are discussed with the conventional ICCG method. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(1): 39–45, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10228 [ABSTRACT FROM AUTHOR]

Coffee berry disease (CBD), caused by Colletotrichum kahawae, is a major constraint for Arabica coffee cultivation in Africa. The disease is specific to green berries and can lead to 60% harvest losses. In Cameroon, mixed cropping systems of coffee with other crops, such as fruit trees, are very widespread agricultural practices. Fruit trees are commonly planted at random on coffee farms, providing a heterogeneous shading pattern for coffee trees growing underneath. Based on a recent study of CBD, it is known that those plants can reduce disease incidence. To assess the specific effect of shade, in situ and in vitro disease development was compared between coffee trees shaded artificially by a net and trees located in full sunlight. In the field, assessments confirmed a reduction in CBD on trees grown under shade compared with those grown in full sunlight. Artificial inoculations in the laboratory showed that shade did not have any effect on the intrinsic susceptibility of coffee berries to CBD. Coffee shading mainly acts on environmental parameters in limiting disease incidence. In addition to reducing yield losses, agroforestry system may also be helpful in reducing chemical control of the disease and in diversifying coffee growers' incomes. [ABSTRACT FROM AUTHOR]

Roads can act as barriers to animal movement through mortality during crossing attempts or behavioral avoidance. This barrier effect has negative demographic and genetic consequences that can ultimately result in local or regional extinction. Here we use radio-telemetry data on three terrestrial vertebrates (eastern massasauga Sistrurus catenatus, eastern box turtle Terrapene carolina and ornate box turtle Terrapene ornata) to test whether roads acted as barriers to movement. Specifically, we test whether individuals avoided crossing roads by comparing the number of observed crossings with the number of road crossings predicted by randomizations of individual movement paths. All species crossed roads significantly less often than predicted by chance, indicating strong road avoidance. Results of this study showing behavioral avoidance and previous studies on road mortality indicate that roads are strong barriers to these species. High mortality during crossing attempts would select for road avoidance, reducing the number of individuals killed on roads over time but leading to genetically partitioned subpopulations due to a lack of gene flow. In species that are long-lived and late-maturing, negative genetic effects might not be observable over short time-scales, thus placing populations at high risk of extinction because of a failure to detect an incrementally worsening problem. Formulating successful management strategies for many species in decline will require integrating data on road mortality, animal behavior and population genetics in order to understand more clearly the barrier effect of roads. [ABSTRACT FROM AUTHOR]

Abstract: Novel polymer/ceramic nanocomposite membranes were fabricated, characterized and tested for their barrier performance. Atomic layer deposition (ALD) was used to deposit alumina films on primary, micron-sized (16 and 60μm) high-density polyethylene (HDPE) particles at a rate of ∼0.5nm/cycle at 77°C. Well-dispersed polymer/ceramic nanocomposites were obtained by extruding alumina coated HDPE particles. The dispersion of alumina flakes can be controlled by varying the number of ALD coating cycles and substrate polymer particle size. The diffusion coefficient of fabricated nanocomposite membranes can be reduced to half with the inclusion of 7.29vol.% alumina flakes. However, a corresponding increase in permeability was also observed due to the voids formed at or near the interface of the polymer and alumina flakes during the extrusion process, as evidenced by electron microscopy. The low surface wettability of the alumina outerlayers was believed to be one of the main reasons of void formation. Particle surface wettability was improved using 3-aminopropyltriethoxysilane (APS) to coat the particle ALD surface modified polymer particles prior to extrusion. The diffusion coefficient and permeability of the membrane using surfactant-modified particles decreased by 20%, relative to the non-modified case. [Copyright &y& Elsevier]

Abstract: Numerous road and railway construction projects include costly mitigation measures to offset the barrier effect produced on local fauna, despite the scarcity of data on the effectiveness of such mitigation measures. In this study, we evaluate the utility of different types of crossing structures. Vertebrate use of 43 transverse crossing structures along the A-52 motorway (north-western Spain) was studied during spring 2001. Research centered on wildlife passages (9), wildlife-adapted box culverts (7), functional passages (6 overpasses, 7 underpasses) and culverts (14), with marble dust being used to record animal tracks. A total of 424 track-days were recorded, with most of the larger vertebrate groups present in the area being detected. All crossing structure types were used by animals, although the intensity of use varied significantly among them (Kruskal–Wallis test, p<0.05); culverts were used less frequently than other structures. Crossing structure type and width were identified as the most important factors in their selection for use. Wildlife passages and adapted culverts allowed crossing by certain species (wild boar, roe deer, Eurasian badger), which do not tend to cross elsewhere. These results highlight the importance of using both mixed-type structures and wildlife passages in reducing the barrier effect of roads. [Copyright &y& Elsevier]

Abstract: The human intestinal microbiota plays a pivotal role in human nutrition and health by promoting the supply of nutrients, preventing pathogen colonization and shaping and maintaining normal mucosal immunity. The depletion of the individual microbiota can result in a higher susceptibility to enteropathogenic bacteria infection. In order to reduce this risk, the use of food supplements containing probiotic bacteria has been recently addressed. In this paper, we investigate the protective role toward enteropathogen infection of probiotic strains belonging to Lactobacillus and Bifidobacterium. According to our experimental data, Lactobacillus acidophilus Bar13, L. plantarum Bar10, Bifidobacterium longum Bar33 and B. lactis Bar30 were effective in displacing the enteropathogens Salmonella typhimurium and Escherichia coli H10407 from a Caco-2 cell layer. Moreover, L. acidophilus Bar13 and B. longum Bar33 have been assessed for their immunomodulatory activity on IL-8 production by HT29 cells. Both strains showed the potential to protect enterocytes from an acute inflammatory response. These probiotic strains are potential candidates for the development of new functional foods helpful in counteracting enteropathogen infections. [Copyright &y& Elsevier]

We conducted a carcass census of Mongolian gazelles (Procapra gutturosa) along the Trans-Mongolian railroad in June 2005. We counted 241 gazelles that had died within the previous 12 months. Carcass numbers were greater on the southwestern side in the northern 3 zones, but we found carcasses only on the northeastern side in the southernmost zone. It suggests that impact of the railroad was stronger on one side and that the strength of this impact varied among regions. [ABSTRACT FROM AUTHOR]

With the Longitudinal Range-Gorge Region (LRGR) in the southwestern China as the object, this research studied how land use pattern varies with the complex topographic features. Based on the 1:50000 digital elevation model (DEM) data and the remote sensing images in 1980, 2001, and by using GIS map algebra method, we investigated the relationship between landform (e.g. elevation and stream networks) and land use, especially the correlation of human activities with the spatial arrangement of the stream networks. This paper reveals that land use and land cover changes in valleys with rich water source at lower elevations are characterized by distinct successional gradients from the river to the upland, which was possibly due to the distance and the availability of water resource. And by dividing the region into four vertical zones according to their elevations, we found that the land use and human activities in each zone were significantly different. Finally, it is indicated that the jamming effects of human activities in the LRGR were spatially heterogeneous and thus led to the barrier effect of stream corridors. [ABSTRACT FROM AUTHOR]

A polymer/polymer composite system is widely used in high-voltage equipment and power cables. The interface of this composite system plays an important role in the electrical degradation, such as electrical treeing or partial discharge, of the composite system. Therefore, it is important to study the effect of an interface on the electrical treeing of polymer/polymer-composite insulating materials. In this paper, we describe the tree growth and complete breakdown characteristics of specimens with a polymer barrier film layer molded in ethylene vinyl acetate copolymer (EVA), in which the interface of EVA and the barrier film is perpendicular to the electric field under an ac voltage. It is found that with a barrier film, the tree growth is retarded on the barrier film, which then punctures the film, or develops along the edge of the film. It is also found that the pressure of decomposing gas in the tree channels plays an important role in tree propagation. [ABSTRACT FROM AUTHOR]

Abstract: Fenced roads fragment terrestrial vertebrate populations, the individuals of which are forced to cross these infrastructures using transverse structures inherent to the road’s construction (culverts, over- and underpasses) or other structures specially adapted or constructed for use by the fauna (enlarged culverts and bridges, ecoducts). The information available on the use of different crossing structure types by vertebrates, and the role played by the structural variables, of the surroundings and of the human use of these passages is still scarce. The use of 82 crossing structures of the A-52 motorway (Zamora, North-western Spain) by terrestrial vertebrates was monitored in summer 2002 using marble dust beds and electronic cameras. A total of 1122 species track-days were recorded, with an average of 1.37 species crossing structure−1 day−1. The results showed that structural aspects were the most determining factors for the species using these passages (MANCOVA test, p &#60;0.001), and a direct positive relationship between the size of the animal and the size of the pass used existing in general terms. This complementary use of the different passage types by vertebrate species suggest that, mitigation measures in new roads should focus to the establishment of several passages of different characteristics instead of investment in a reduced number of large fauna-specific passages. [Copyright &y& Elsevier]

Abstract: Roads and traffic affect animal populations detrimentally in four ways: they decrease habitat amount and quality, enhance mortality due to collisions with vehicles, prevent access to resources on the other side of the road, and subdivide animal populations into smaller and more vulnerable fractions. Roads will affect persistence of animal populations differently depending on (1) road avoidance behavior of the animals (i.e., noise avoidance, road surface avoidance, and car avoidance); (2) population sensitivity to the four road effects; (3) road size; and (4) traffic volume. We have created a model based on these population and road characteristics to study the questions: (1) what types of road avoidance behaviors make populations more vulnerable to roads?; (2) what types of roads have the greatest impact on population persistence?; and (3) how much does the impact of roads vary with the relative population sensitivity to the four road effects? Our results suggest that, in general, the most vulnerable populations are those with high noise and high road surface avoidance, and secondly, those with high noise avoidance only. Conversely, the least vulnerable populations are those with high car avoidance only, and secondly, high road surface and high car avoidance. Populations with low overall road avoidance and those with high overall road avoidance tend to respond in opposite ways when the sensitivity to the four road effects is varied. The same is true of populations with high road surface avoidance when compared to those with high car and high noise avoidance. The model further predicted that traffic volume has a larger effect than road size on the impact of roads on population persistence. One potential application of our model (to run the model on the web or to download it go to www.glel.carleton.ca/ or www.nls.ethz.ch/roadmodel/index.htm or contact the first author) is to generate predictions for more structured field studies of road avoidance behavior and its influence on persistence of wildlife populations. [Copyright &y& Elsevier]

Roads affect animal populations in three adverse ways. They act as barriers to movement, enhance mortality due to collisions with vehicles, and reduce the amount and quality of habitat. Putting fences along roads removes the problem of road mortality but increases the barrier effect. We studied this trade-off through a stochastic, spatially explicit, individual-based model of population dynamics. We investigated the conditions under which fences reduce the impact of roads on population persistence. Our results showed that a fence may or may not reduce the effect of the road on population persistence, depending on the degree of road avoidance by the animal and the probability that an animal that enters the road is killed by a vehicle. Our model predicted a lower value of traffic mortality below which a fence was always harmful and an upper value of traffic mortality above which a fence was always beneficial. Between these two values the suitability offences depended on the degree of road avoidance. Fences were more likely to be beneficial the lower the degree of road avoidance and the higher the probability of an animal being killed on the road. We recommend the use of fences when traffic is so high that animals almost never succeed in their attempts to cross the road or the population of the species of concern is declining and high traffic mortality is known to contribute to the decline. We discourage the use of fences when population size is stable or increasing or if the animals need access to resources on both sides of the road, unless fences are used in combination with wildlife crossing structures. In many cases, the use offences may be beneficial as an interim measure until more permanent measures are implemented. [ABSTRACT FROM AUTHOR]

The ability of animal species to disperse through matrix habitats is likely to have important implications for species' responses to habitat fragmentation. Within fragmented forests, open fields are among the most common matrix habitats. However, few empirical studies have measured the effects of open habitats on dispersal success of forest- dwelling species. We used two experiments to determine the effects of open habitats and distance on dispersal and colonization by red-backed salamanders, Plethodon cinereus. In the first experiment, salamanders were displaced from habitat edges 25 m and 55 m into an open field and farther into the forest. Return rates from salamanders crossing the field vs. the forest were then used to determine the barrier effects of open habitats. Although return rate declined with distance, salamanders returned successfully through open habitat as often as they returned successfully through forest. In the second experiment, we constructed "islands" of forest-like habitat within an open field. As in the previous experiment, colonization declined with distance. However, salamanders did colonize most of these field plots within one year. Initial colonists tended to be in the size range of young adults, suggesting that there may be a distinct dispersal phase for terrestrial salamanders. Collectively, these results suggest that even relatively sedentary species may be able to move through matrix habitats that are otherwise little used. Given that red-backed salamanders appear to be relatively abundant in fragmented forests, we suggest that movement through open habitats could help to offset some of the negative effects of habitat fragmentation. [ABSTRACT FROM AUTHOR]

Abstract: We studied the in vitro effects of a range of ciprofloxacin (CI) concentrations on the human intestinal flora’s colonization resistance (CR) to Salmonella kedougou NCTC 12173. Four steady state microbial communities were established in chemostats using inocula from a single pool of human feces. Three chemostats were exposed to CI (0.1, 0.43 and 5 μg/mL, respectively); one served as a no-drug control. The CR of each community was tested by three successive daily challenges of 108 S. kedougou, each delivered in a 1 mL bolus. There was no colonization of the no-drug chemostat. Likewise, after exposure to only 0.1 μg/mL CI there was no loss of CR and S. kedougou did not colonize. Conversely, both the 0.43 and the 5 μg/mL-exposed floras suffered a loss of CR and these chemostats were colonized. S. kedougou overgrew faster and reached higher counts in the presence of 0.43 than it did in the presence of 5 μg/mL. One possible explanation is that CI had a dose-dependent effect on both the challenge strain and CR. Thus, at higher levels, even though CR was disrupted by CI, so too was the growth of the challenge strain. Since exposure to CI elicited a dose-dependent reduction in Escherichia coli counts [Reg. Pharmacol. Toxicol. 33 (2001) 276] our new data suggest that E. coli may contribute to the CR against salmonella. We further conclude that, even at fecal levels below those reached during therapy, CI may impact the human gut flora sufficiently to facilitate colonization by S. kedougou. [Copyright &y& Elsevier]

Up to 90% of the fatigue life of engineering alloys results from the initiation and propagation of microstructurally short cracks. Owing to their strong interactions with microstructural features, e.g. grain and phase boundaries, they exhibit substantially non-uniform propagation kinetics as compared with the growth rate of long cracks, which can be well described using a power-law function of the range of the stress-intensity factor Δ K. In the present paper interactions between the crystallographic misorientation of grain and phase boundaries and microcracks in an austenitic/ferritic stainless steel are discussed and quantified by means of fatigue experiments in combination with the electron backscattered diffraction technique. In the second part a numerical model for the simulation of microcracks is introduced, which is capable of taking real microstructural arrangements into consideration. [ABSTRACT FROM AUTHOR]

In the response to an increasing demand for electrical energy, much effort aimed to develop and commercialise HTS power equipments is going on around the world. For the development, it is necessary to establish the dielectric technology in LN2. Hence many types of dielectric tests should be carried out to understand the dielectric phenomena at cryogenic temperature and to gather various dielectric data. Among the many types dielectric tests, the characteristic of surface flashover and the barrier effect were conducted with the simulated electrode after analysing the insulating configuration of the pancake-coil-type HTS transformer. The influence of a barrier on the dielectric strength was measured according to the size of the barrier, the position of the barrier and the effect of the back-electrode. It was shown that the effectiveness, namely the ratio of the breakdown voltage in presence of barrier to the voltage without barrier, is highest when the barrier is placed at the needle electrode side. The effect increased up to 1.8 times when collar length is 10 mm. The flashover characteristic with back-electrode was remarkably lower than the characteristic without one in the case the electrodes located at the same surface of dielectric plate. On the contrary, in the case the barrier was placed between the electrodes, the characteristic was even improved slightly. [Copyright &y& Elsevier]

Intensively coloured mica pigments based on mica flakes covered with surface oxide–hydroxide layer of different metals, such as Ti, Cr, Fe, Al, Co, Ni, Zn and Cu were prepared by homogeneous precipitation of metal sulphates with urea in the presence of mica flakes. The final colour was obtained by thermal annealing of precipitates at temperature 150–800 °C. [Copyright &y& Elsevier]

Summary1.Drainage culverts are ubiquitous features in road corridors, yet little is known about the efficacy of culverts for increasing road permeability and habitat connectivity for terrestrial wildlife. Culvert use by small- and medium-sized mammals was investigated along roads in Banff National Park, Alberta, Canada. An array of culvert types was sampled varying in dimensions, habitat and road features during the winters of 1999 and 2000. Expected passage frequencies were obtained by sampling relative species abundance along transects at the ends of each culvert. 2.Weasels Mustela erminea and M. frenata and deer mice Peromyscus maniculatus used the culverts for passage most frequently, whereas red squirrels Tamiasciurus hudsonicus and snowshoe hares Lepus americanus were the most common small mammals in the study area according to transects sampled near each culvert. 3.Species’ performance indices (observed crossing vs. expected crossing) were calculated for five species by comparing their tracks inside and adjacent to 36 culverts. Culvert performance indices were significantly different between the five species: culvert attributes influenced species’ use but different attributes appeared to affect use by different species. 4.At all scales of resolution (species, species group and community level), traffic volume, noise levels and road width ranked high as significant factors affecting species’ use of the culverts. Passage by American martens Martes americana , snowshoe hares and red squirrels all increased with traffic volume, the most important variable. Coyote Canis latrans use of culverts was negatively correlated with traffic volume. Increasing noise and road width appeared to be negative influences on culvert passage by coyotes, snowshoe hares and red squirrels. 5.Structural variables partially explained passage by weasels and martens. Weasel passage was positively correlated with culvert height but negatively correlated with culvert openness. Martens preferred culverts with low clearance and high openness ratios. High through-culvert visibility was important for snowshoe hares but not for weasels. The passage by weasels and snowshoe hares was positively correlated with the amount of vegetative cover adjacent to culverts. 6.For many small- and medium-sized mammals drainage culverts can mitigate the potentially harmful effects of busy transport corridors by providing a vital habitat linkage. To maximize connectivity across roads for mammals, future road construction schemes should include frequently spaced culverts of mixed size classes and should have abundant vegetative cover present near culvert entrances. Further work is required to assess the effects of culverts on population demography and gene flow adjacent to large roads. [ABSTRACT FROM AUTHOR]

Electrical mass transfer of amino acids through ion-exchange membranes is modeled experimentally by the laser-interferometry method. A direct proof is obtained for the barrier effect in electrodialysis of solutions of amino acids at current densities exceeding the limiting value. [ABSTRACT FROM AUTHOR]