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Vertical Distance (vertical + distance)
Selected AbstractsNanoarrays: Cooperative Near-Field Surface Plasmon Enhanced Quantum Dot Nanoarrays (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Mater. Abstract Fluorescence from quantum dots (QDs) sandwiched between colloidal gold nanoparticles and lithographically created metal nanoarrays is studied using engineered peptides as binding agents. For optimized structures, a 15-fold increase is observed in the brightness of the QDs due to plasmon-enhanced fluorescence. This enhanced brightness is achieved by systematically tuning the vertical distance of the QD from the gold nanoparticles using solid-specific peptide linkers and by optimizing the localized surface plasmon resonance by varying the geometric arrangement of the patterned gold nanoarray. The size and pitch of the patterned array affect the observed enhancement, and sandwiching the QDs between the patterned features and colloidal gold nanoparticles yields even larger enhancements due to the increase in local electromagnetic hot spots induced by the increased surface roughness. The use of bifunctional biomolecular linkers to control the formation of hot spots in sandwich structures provides new ways to fabricate hybrid nanomaterials of architecturally induced functionality for biotechnology and photonics. [source] Cooperative Near-Field Surface Plasmon Enhanced Quantum Dot NanoarraysADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Kirsty Leong Abstract Fluorescence from quantum dots (QDs) sandwiched between colloidal gold nanoparticles and lithographically created metal nanoarrays is studied using engineered peptides as binding agents. For optimized structures, a 15-fold increase is observed in the brightness of the QDs due to plasmon-enhanced fluorescence. This enhanced brightness is achieved by systematically tuning the vertical distance of the QD from the gold nanoparticles using solid-specific peptide linkers and by optimizing the localized surface plasmon resonance by varying the geometric arrangement of the patterned gold nanoarray. The size and pitch of the patterned array affect the observed enhancement, and sandwiching the QDs between the patterned features and colloidal gold nanoparticles yields even larger enhancements due to the increase in local electromagnetic hot spots induced by the increased surface roughness. The use of bifunctional biomolecular linkers to control the formation of hot spots in sandwich structures provides new ways to fabricate hybrid nanomaterials of architecturally induced functionality for biotechnology and photonics. [source] Interpretation of observed fluid potential patterns in a deep sedimentary basin under tectonic compression: Hungarian Great Plain, Pannonian BasinGEOFLUIDS (ELECTRONIC), Issue 1 2001J. Tóth Abstract The , 40 000 km2 Hungarian Great Plain portion of the Pannonian Basin consists of a basin fill of 100 m to more than 7000 m thick semi- to unconsolidated marine, deltaic, lacustrine and fluviatile clastic sediments of Neogene age, resting on a strongly tectonized Pre-Neogene basement of horst-and-graben topography of a relief in excess of 5000 m. The basement is built of a great variety of brittle rocks, including flysch, carbonates and metamorphics. The relatively continuous Endr,d Aquitard, with a permeability of less than 1 md (10,15 m2) and a depth varying between 500 and 5000 m, divides the basin's rock framework into upper and lower sequences of highly permeable rock units, whose permeabilities range from a few tens to several thousands of millidarcy. Subsurface fluid potential and flow fields were inferred from 16 192 water level and pore pressure measurements using three methods of representation: pressure,elevation profiles; hydraulic head maps; and hydraulic cross-sections. Pressure,elevation profiles were constructed for eight areas. Typically, they start from the surface with a straight-line segment of a hydrostatic gradient (,st = 9.8067 MPa km,1) and extend to depths of 1400,2500 m. At high surface elevations, the gradient is slightly smaller than hydrostatic, while at low elevations it is slightly greater. At greater depths, both the pressures and their vertical gradients are uniformly superhydrostatic. The transition to the overpressured depths may be gradual, with a gradient of ,dyn = 10,15 MPa km,1 over a vertical distance of 400,1000 m, or abrupt, with a pressure jump of up to 10 MPa km,1 over less than 100 m and a gradient of ,dyn > 20 MPa km,1. According to the hydraulic head maps for 13 100,500 m thick horizontal slices of the rock framework, the fluid potential in the near-surface domains declines with depth beneath positive topographic features, but it increases beneath depressions. The approximate boundary between these hydraulically contrasting regions is the 100 m elevation contour line in the Duna,Tisza interfluve, and the 100,110 m contours in the Nyírség uplands. Below depths of ,,600 m, islets of superhydrostatic heads develop which grow in number, areal extent and height as the depth increases; hydraulic heads may exceed 3000 m locally. A hydraulic head ,escarpment' appears gradually in the elevation range of ,,1000 to ,,2800 m along an arcuate line which tracks a major regional fault zone striking NE,SW: heads drop stepwise by several hundred metres, at places 2000 m, from its north and west sides to the south and east. The escarpment forms a ,fluid potential bank' between a ,fluid potential highland' (500,2500 m) to the north and west, and a ,fluid potential basin' (100,500 m) to the south and east. A ,potential island' rises 1000 m high above this basin further south. According to four vertical hydraulic sections, groundwater flow is controlled by the topography in the upper 200,1700 m of the basin; the driving force is orientated downwards beneath the highlands and upwards beneath the lowlands. However, it is directed uniformly upwards at greater depths. The transition between the two regimes may be gradual or abrupt, as indicated by wide or dense spacing of the hydraulic head contours, respectively. Pressure ,plumes' or ,ridges' may protrude to shallow depths along faults originating in the basement. The basement horsts appear to be overpressured relative to the intervening grabens. The principal thesis of this paper is that the two main driving forces of fluid flow in the basin are gravitation, due to elevation differences of the topographic relief, and tectonic compression. The flow field is unconfined in the gravitational regime, whereas it is confined in the compressional regime. The nature and geometry of the fluid potential field between the two regimes are controlled by the sedimentary and structural features of the rock units in that domain, characterized by highly permeable and localized sedimentary windows, conductive faults and fracture zones. The transition between the two potential fields can be gradual or abrupt in the vertical, and island-like or ridge-like in plan view. The depth of the boundary zone can vary between 400 and 2000 m. Recharge to the gravitational regime is inferred to occur from infiltrating precipitation water, whereas that to the confined regime is from pore volume reduction due to the basement's tectonic compression. [source] Temporal variations of physical and hydrochemical properties of springs in the Mid-Levels area, Hong Kong: results of a 1-year comprehensive monitoring programmeHYDROLOGICAL PROCESSES, Issue 8 2008Chi-Man Leung Abstract Springs and seeps occur in the spaces around Po Hing Fong Street in the Mid-Levels area, Hong Kong. Most of the springs occur through the drainage weepholes on retaining walls at the street. This paper first examines the geology and history of the springs. The paper then reports the findings from a 1-year comprehensive spring monitoring programme. The temporal variations of flow rate, physiochemical parameters and hydrochemistry of the springs are discussed. The average temperatures of the springs were close to the mean air temperature, although there was a systematic lag time of 40 to 50 days between the peak air temperature and highest water temperatures. Spring waters from two rows of weepholes in the retaining wall showed significantly different physical and hydrochemical responses to the changes in rainfall and temperature, though their vertical distance is only about 1 m. The results suggest that water from the upper row of weepholes may represent a recharge source that is shallow or close to the spring outlets, whereas that from the lower row of weepholes may represent a recharge source that is much deeper or further up the hill. Although the spring flows increased rapidly after rainstorms, analysis of the total dissolved solids showed a delayed response to rainstorm events. The concentration of individual ions in the spring water varied in a unique way in response to rainstorm events. It is clear that the presence of underground man-made drainage systems and the leakage from water mains in the study area may add complexity to the solute responses and transport mechanisms. Further studies are required to constrain the impacts of these man-made structures on the hydrogeology of the springs. Copyright © 2007 John Wiley & Sons, Ltd. [source] Aspects on the relief of living surfaces using atomic force microscopy allow "art" to imitate natureINTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 3 2010Rosa POLYMENI Abstract The visualization of the surface of biological samples using an atomic force microscope reveals features of the external relief and can resolve very fine and detailed features of the surface. We examined specimens from the skin of the amphibians Salamandra salamandra Linnaeus, 1758, Lyciasalamandra luschani basoglui Baran & Atatür, 1980 and Mesotriton alpestris Laurenti, 1768, and from the surface of pollen grains of the plant species Cyclamen graecum Link, 1835 and Cistus salviifolius Linnaeus, 1753, which exhibit certain interesting features, imaged at the nanoscale level. It is likely that the relief influences the attributes of the interfaces between the tissues and the environment. We found that the microsculpture increases in size the surface of the examined tissues and this might be particularly important for their performance in the field. Microsculpturing of amphibians' skin may affect water regulation, dehydration and rehydration, and cutaneous gas exchange. Pollen grain relief might affect the firmness of the contact between pollen surface and water droplets. High resolution imaging of the external relief showed that roughening might induce wetting and influence the water status of the specimens. In addition, roughness affects the radius of water droplets retained in between the projections of the external relief. Roughness of the tissues was highly correlated with their vertical distance, whereas surface distances were highly correlated with horizontal distances. By enabling a more detailed characterization of the external sculptures, through sophisticated techniques, a more comprehensive examination of the samples indicates similarities among different living tissues, originated from different kingdoms, which can be attributed to environmental conditions and physiological circumstances. [source] Up, up, and away: relative importance of horizontal and vertical escape from predators for survival and senescenceJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 8 2010A. P. MØLLER Abstract Animals fleeing a potential predator can escape horizontally or vertically, although vertical flight is more expensive than horizontal flight. The ability to escape in three dimensions by flying animals has been hypothesized to result in greater survival and eventually slower senescence than in animals only fleeing in two dimensions. In a comparative study of flight initiation distance in 69 species of birds when approached by a human, I found that the amount of variance explained by flight initiation distance was more than four times as large for the horizontal than the vertical component of perch height when taking flight. The slope of the relationship between horizontal distance and flight initiation distance (horizontal slope) increased with increasing body mass across species, whereas the slope of the relationship between vertical distance and flight initiation distance (vertical slope) decreased with increasing body mass. Therefore, there was a negative relationship between horizontal and vertical slope, although this negative relationship was significantly less steep than expected for a perfect trade-off. The horizontal slope decreased with increasing density of the habitat from grassland over shrub to forest, whereas that was not the case for the vertical slope. Adult survival rate increased and rate of senescence (longevity adjusted for survival rate, body mass and sampling effort) decreased with increasing vertical, but not with horizontal slope, consistent with the prediction that vertical escape indeed provides a means of reducing the impact of predation. [source] Individual difference in the number of chewing strokes and its determinant factorsJOURNAL OF ORAL REHABILITATION, Issue 2 2006T. UEDA summary, This study was carried out to clarify the distribution and individual variation of the number of chewing strokes before last swallowing (NCS), as well as to assess the factors that affect NCS, when dentulous adults masticate the same type of food. NCS was measured in 75 dentulous adults using gummy candies. Measurements were repeated five times to obtain the average and variation. Moreover, the correlation of NCS with various physiological factors (lateral width and vertical distance of chewing loop, angle of opening and closing path, opening and closing time, occlusal time, masticatory performance, number of occlusal contact points, occlusal contact area, occlusal force, flow rate of whole saliva and viscosity of whole saliva) and 28 personality factors were analysed by both of the single variate analysis and the multivariate analysis. The results showed that the average NCS was 41·0 ± 16·0, and the coefficient of variation was 0·090 ± 0·040. Additionally, the correlation between NCS and each factor was investigated, and found that any of these factors did not function as a single determinant for NCS. Following, determinant factors were further examined by the stepwise method of linear multiple regression analysis. From these analysis we found that when opening and closing time and four personality factors were combined, they were significantly involved in determining NCS (P < 0·01). Therefore, we conclude that individual NCS until last swallowing is not determined by a sole, specific physiological factor but is affected by multiple factors including personality. [source] Measurement of Horizontal and Vertical Movement of Ralstonia solanacearum in SoilJOURNAL OF PHYTOPATHOLOGY, Issue 10 2006M. Satou Abstract Two model systems were constructed to measure horizontal and vertical movement of bacteria in soil. These systems were applied to measuring movement of Ralstonia solanacearum (race 1, biovar 3), a causal agent of bacterial wilt of tomato, in andosol and sand at 28°C. The first system was used to measure horizontal movement of the bacteria in soil packed in a narrow horizontal frame. Suspension of the pathogen was applied to soil at one end of the frame, and bacterial number per gram of soil was measured over distance from the inoculation point after 4 days. Horizontal movement of R. solanacearum in supersaturated soil, but without flow, was possibly due to diffusion and the front advanced at 2.2 cm/day in andosol, and at 8.1 cm/day in sand. Using the same experimental system, but applying water inflow to one end of the frame only, the bacterium was detected at the front of water in andosol and sand. The front of the distribution advanced at 20.4 cm/h in andosol and 66.3 cm/h in sand. In the second experimental system, a cylinder of soil packed in a short tube was soaked with water, and soil at the top of the tube was inoculated with bacterial suspension. Immediately, soil cylinders were turned upward, and the bacterial number per gram of soil was measured along vertical distance from the inoculation point after 7 days. Using the system with andosol, the capillary water front rose to 32.5 cm over 7 days after inoculation, and R. solanacearum reached to 18.8 cm height. In sand, capillary water rose to 20.0 cm and the bacteria reached to 16.3 cm height. [source] Bahnsteigerweiterung der U6 unter dem neuen Rathaus in München , Spritzbetonvortrieb mit VereisungBAUTECHNIK, Issue 7 2005Jochen Fillibeck Dr.-Ing. Im Rahmen der Infrastrukturmaßnahmen für den Bau des neuen Fußballstadions in Fröttmaning wurde es erforderlich, die Bahnsteige der U-Bahnlinie U6 unter dem Rathaus in München zu erweitern. Nach dem Entwurf des Baureferats der Landeshauptstadt München wurde hierzu parallel und im direkten Anschluß an die beiden bestehenden Tunnelröhren je ein Tunnel in Spritzbetonbauweise unter atmosphärischen Bedingungen ausgeführt. Die Vortriebe liegen in einem vertikalen Abstand von ca. 10 m zum Münchner Rathaus. Zur Sicherung der Firste und zur Reduzierung der Verformungen wurden im Rahmen eines Sondervorschlags Vereisungsschirme vorgesehen, die von einem über der Firste befindlichen Pilotstollen aus hergestellt wurden. Für die erfolgreiche Umsetzung des Bauvorhabens war es entscheidend, welche Verformungen , Hebungen in der Gefrierphase und Setzungen während des Vortriebs , sich mit dem Baufortschritt einstellen. Dies wurde vorab anhand von Frostversuchen im Labor und mit FE-Berechnungen untersucht. Durch einen Vergleich der Berechnungsergebnisse mit den umfangreichen Kraft- und Verformungsmessungen während des Vortriebs konnte zu jedem Zeitpunkt ein verformungsarmer Tunnelvortrieb mit tolerierbaren Baugrundverformungen sichergestellt werden. Im folgenden Beitrag werden die wesentlichen Berechnungen und Meßergebnisse zu den Baugrundverformungen und zur Wasserhaltung und die Maßnahmen zur Reduzierung der Frosthebungen erläutert. Ferner werden durch einen Vergleich der Bau- und Berechnungsweisen der alten Bestandstunnels mit dem neuen Erweiterungstunnel die mit der Spritzbetonbauweise einhergehenden Entwicklungen im Tunnelbau veranschaulicht. Platform extension of the subway U6 below the historical town hall in Munich , shotcrete method combined with ground freezing. The construction of the new football stadium in Munich-Fröttmaning made it necessary to extend the platform of the subway station U6 "Marienplatz" below the historical town hall of Munich. For this, two new tunnels for pedestrians were driven parallel to the existing subway tunnels. They were planned as shotcrete construction and driven under atmospheric conditions. The tunnels have a vertical distance of approx. 10 m to the foundation of the town hall. Artificial ground freezing was used to guarantee the stability and safety of the tunnel roof and to reduce the deformations. The freezing pipes were implemented in a smaller pilot tube lateral above the tunnels. Both the magnitude of the frost heave displacements and the settlements had to be predicted prior to undertake the construction. Therefore frost heave tests and FE-computations were carried out. During the construction process these results were permanently compared to measurements in order to control and ensure tolerable deformations. In the following contribution the substantial computations and results of measurement relating to the ground deformations and to the lowering of groundwater are described. Furthermore the methods for the reduction of the frost heave are explained. A comparison of the methods of construction and calculation of the old tunnels and the new tunnels illustrates the developments in tunnel construction resulting from the shotcrete method. [source] Species richness,standing crop relationship in stream bryophyte communities: patterns across multiple scalesJOURNAL OF ECOLOGY, Issue 1 2001Risto Virtanen Summary 1,We tested for a unimodal (,hump-backed') relationship between species richness and standing crop at various spatial scales in stream bryophyte communities. Bryophyte species and their biomasses were determined from 20 to 25 quadrats in eight river and six stream sites in northern Finland. 2,Regression analyses revealed a quadratic relationship between richness and biomass in only two of the river sites and a positive correlation in one other. A quadratic relationship was detected in three stream sites and richness increased linearly with biomass in another. 3,We also tested for the hump-shaped pattern across individual stream boulders, representing an elevational gradient from continuously submerged to permanently dry conditions, with an intermediate zone with fluctuating water level. 4,Species richness-standing crop relationship conformed to the hump-backed model only when samples from all three microhabitats were included in the analysis. A significant positive correlation occurred in the exposed low biomass end of the gradient which is characterized by semi-aquatic species, whereas the relationship tended to be negative in permanently submerged areas with high biomass of large canopy-forming species. Quadrats close to the water level had intermediate standing crop and highest species richness. 5,Species dominant at either end of the gradient appeared unable to monopolize space in the intermediate zone where disturbances (e.g. scouring by ice) detach mosses from the substratum, creating vacant gaps for colonization. The unimodal relationship between richness and biomass is likely to occur only in streams that contain large boulders protruding above the water line, thus providing scope for community diversification along very short vertical distances. [source] Small unilateral jaw gap variations: equilibrium changes, co-contractions and joint forcesJOURNAL OF ORAL REHABILITATION, Issue 10 2009H. J. SCHINDLER Summary, After complex prosthetic reconstructions, small differences in vertical distances between the left and right side of the jaw may occur during jaw closing, nevertheless providing bilateral tooth contacts in intercuspation by small deformations of the mandible. Their effects on the co-contraction of the masticatory muscles, the temporomandibular joint reaction forces, and the point of application of the resultant bite force vector in the maxillary occlusion plane , the so-called reduction point , have not been investigated, thus far simultaneously in one sample. The main goal of this study was to investigate variations of these measures in an experimental intercuspation simulated by one anterior and two posterior force transmission points. [source] Distribution of benthic communities in the fjord-like Bathurst Channel ecosystem, south-western Tasmania, a globally anomalous estuarine protected areaAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2010Neville S. Barrett Abstract 1.Benthic assemblages in the fjord-like Bathurst Channel estuarine system, south-western Tasmania, vary over horizontal scales of 1,5,km and vertical scales of 1,10,m. Multivariate analysis indicated a total of eight major assemblages that characterize different sections and depths of the channel. 2.Because tannins in the low-salinity surface water layer block light, foliose algae reach 5,m depth in the marine western region but do not penetrate below 1,m in the east. By contrast, sessile invertebrates are most abundant below 5,m depth in the west and below 2,m in the east. Deeper assemblages are unlikely to be continuous with assemblages in deeper waters off the Tasmanian coast as they are highly constrained by depth within particular sections of the estuary. 3.While the species composition of the Bathurst Channel biota is most similar to that found elsewhere in Tasmania, the structural character of the biota in terms of major taxonomic groups is more closely allied to that found in fjords of south-western Chile and south-western New Zealand. These three regions all possess wilderness settings, high rainfall that is channelled through estuaries as a low-salinity surface layer, deep-water emergence of fauna, rapid change in biotic communities over short horizontal and vertical distances, and high levels of local endemism. They also include some of the most threatened aquatic ecosystems on earth due to increasing human activity from a near pristine base, and the potentially catastrophic impacts of climate change. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||