Areas Of High Flow Research Articles

Mobile Particle and NOx Emission Characterization at Helsinki Downtown: Comparison of Different Traffic Flow Areas

A two weeks measurement campaign by a mobile laboratory van was performed at downtown Helsinki, Finland, in winter 2010. The characteristics of air pollutants such as fine particles in the size ranges of 7–40 nm (Np40) and 40–1000 nm (Np1000), black carbon (BC), fine particle mass (PM2.5), as well as gaseous compounds NO, NO2, NOx, CO and CO2 were studied. The statistical analysis showed that the air pollution conditions strongly depended on the traffic flow area; therefore, the street sections were classified as high traffic flow areas (HTF1-HTF4), low traffic flow areas (LTF1-LTF5), and urban background areas (BG1-BG3). Large variation of particle emissions was observed, and the momentary peak particle concentrations were 8 × 105 cm–3. At the HTF areas exhaust emissions followed clearly daily average heavy duty vehicle counts rather than the average daily vehicle counts. Higher correlation coefficients were found between CO2 and NO than between CO2 and Ntot. The dispersion studies indicated that the air pollution conditions strongly improved from high traffic flow areas to low traffic flow areas. Therefore, proper city planning and locating, for example, cycle tracks, schools and hospitals farther from busy city streets might significantly reduce exposure risk for humans.

Behavioral correction to prevent overhydration and increase survival by larvae of the net-spinning caddisflies in relation to water flow.

We report behavioral regulation of body water content in caddisfly larvae, Hydropsyche morosa and Cheumatopsyche pettiti, by selecting microhabitats with different water flow rates. The purpose of our study was to examine features necessary for survival in the same apparent habitat, because the two species co-exist in riffle areas of freshwater streams. Both species are highly sensitive to water loss as a result of high water loss rates and depend on immersion in fresh water (hypo-osmotic) to maintain water stores. In contrast to C. pettiti, H. morosa is larger, retains water more effectively, and features reduced water loss rates with suppressed activation energies. When H. morosa was confined to areas of low or no water flow, overhydration led to rapid mortality, whereas the same conditions favored water balance maintenance and survival in C. pettiti. In attraction bioassays, H. morosa moved and remained within areas of high water flow and C. pettiti preferred areas with low water flow. Because water flow rates are unlikely to directly impact water gain, the mechanism responsible for increased survival and water balance maintenance is likely related to the impact of water flow on oxygen availability, differences in feeding ecology, or other underlying factors.

The diagenetic destruction of porosity in plutoniclastic petrofacies: The Miocene Diligencia and Eocene Maniobra formations, Orocopia Mountains, southern California, USA

Abstract The Miocene Diligencia Formation of southern California was deposited in an alluvial/fluvial depositional system developed within the Diligencia basin. This basin formed as an extensional half-graben during latest Oligocene–Early Miocene crustal extension. This continental half-graben was superposed on an Eocene fault-controlled submarine canyon, in which the Maniobra Formation was deposited. The arkosic composition of the sandstone framework would predict a high-quality reservoir with preserved primary porosity or at least important intergranular volume (IGV). However, inspection of sandstone samples indicates that diagenesis was intense, as several diagenetic processes drastically reduced the reservoir quality. Dominant diagenetic processes were compaction and cementation. Mechanical compaction, expressed as intense deformation of ductile grains and chemical compaction in the form of pressure solution, reduced the IGV of sandstone at the bases of the Maniobra and Diligencia formations to low levels (10–20%). In the upper parts of both units, early diagenetic cements partially inhibited compaction, maintaining IGV values close to 35%. Several mineral phases constitute cements responsible for occlusion of primary porosity. Many of these phases also replaced framework components and early cements. The more important cements are: (1) quartz and K-feldspar, which appear mainly as grain overgrowths, although quartz mosaics have been observed at the base of the Maniobra Formation; (2) carbonates, such as ankerite, dolomite and calcite in diverse textures and with significant occluding character; (3) phyllosilicates, such as kaolin, that developed mainly in Diligencia sandstone as early pore fillings, and locally as illite coats around detrital grains; and (4) other mineral phases, such as Fe-oxides and fluorite, which occur exclusively at the base of the Maniobra Formation, exhibiting aggressive textures against framework grains and older cements. The chronology of diagenetic processes includes marine early diagenesis (eodiagenesis) for Maniobra sandstone, characterized by K-feldspar, ankerite and dolomite cements. Continental early diagenesis is identified in Diligencia sandstone, manifested by the presence of smectite (replaced by illite), kaolin and Fe-oxide cements. Mesodiagenetic processes are similar in both formations. In addition, hydrothermal phases (fluorite and quartz mosaics) are identified at the base of the Maniobra Formation. Diagenetic mineral associations suggest palaeotemperatures above 130 °C. The geotectonic scenario in which diagenesis occurred explains these post-depositional processes. During latest Oligocene–Early Miocene crustal extension, the Diligencia basin developed in an area of high heat flow, as expressed in the eruption of interbedded basaltic–andesitic lavas. High heat flow favoured compaction and cementation, accelerating these diagenetic processes during a relative short time interval. Hydrothermal fluxes produced mineral phases that contributed to the destruction of a potentially good reservoir by intense diagenesis. Supplementary material: Optical analysis: point count and recalculated parameters are available at http://www.geolsoc.org.uk/SUP18650 .

Blood pressure cuffs as a vector for transmission of multi‐resistant organisms: Colonisation rates and effects of disinfection

Blood pressure (BP) cuffs are potential vectors for transmission of multi-resistant organisms (MROs). The present study aims to determine MRO colonisation rates in BP cuffs from areas of high patient flow as an assessment of the quality of disinfection and infection control practices. BP cuffs in the ED, high dependency unit (HDU) and operating theatres (OT) were prospectively examined after routine disinfection procedures. Swabs collected from the inner and outer surfaces of BP cuffs during inter-patient intervals were plated onto replicate organism detection and counting, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) chromogenic agar plates to detect rates of bacterial, MRSA and VRE colonisation, respectively. High bacterial colonisation rates were detected in BP cuffs from all three areas. BP cuffs from OT were significantly less colonised compared with cuffs from HDU and ED; 76% versus 96% and 100% (P < 0.0001) for inner surfaces and 86% versus 98% and 100% (P < 0.0001) for outer surfaces, respectively. Equivalent or higher bacterial growth was observed on the inner surface compared with outer surface in 54%, 84% and 86% of BP cuffs from OT, HDU and ED, respectively. MRSA was detected in 3 of 150 (2%) swabs collected, but no VRE was detected. Although MRSA and VRE were infrequently isolated, current disinfection and infection control protocols need to be improved given the greater recovery of organisms from the inner compared with outer surfaces of BP cuffs.

Hydrothermally altered mudrock of the Ciñera-Matallana coal basin, Cantabrian Zone, northern Spain

An X-ray diffraction and electron microscopy study of very-low-grade metamorphic clay mineral assemblages of Upper Carboniferous (Stephanian) mudrocks from the coal-bearing Cinera-Matallana basin of NW Spain reveals a complex mineralization history related to localized igneous and hydrothermal activity associated with strike-slip-faulting. This thermally active, pull-apart basin experienced peak temperatures (up to ca . 296 C) that reached anchizonal grades in areas of high heat and fluid flow, with hot hydrothermal growth of well crystallized 2 M 1 illite–muscovite, chlorite, and pyrophyllite occurring pre- and synchronous with Late Carboniferous/Early Permian folding and faulting of the sedimentary sequence. No burial pattern could be recognized in the clay mineral reactions with stratigraphic depth due to the complexities of hydrothermal alteration. Clay mineral growth was controlled by the location of igneous activity and the circulation of CH 4 -bearing fluids released during the maturation of coal seams and dispersed organic matter. Extensive retrograde reaction to illite-smectite (1 M d polytype) with abundant R1 rectorite (50–50) in altered rocks adjacent to igneous intrusions and along faults is attributed to the circulation of cooler (

Noninvasive parametric blood flow imaging of head and neck tumours using [15O]H2O and PET/CT

The aim of this study was to develop a simple noninvasive method for measuring blood flow using [15O]H2O PET/CT for the head and neck area applicable in daily clinical practice. Fifteen dynamic [15O]H2O PET emission scans with simultaneous online radioactivity measurements of radial arterial blood [Blood-input functions (IFs)] were performed. Two noninvasively obtained population-based input functions were calculated by averaging all Blood-IF curves corrected for patients' body mass and injected dose [standardized uptake value (SUV)-IF] and for body surface area (BSA-IF) and injected dose. Parametric perfusion images were calculated for each set of IFs using a linearized two-compartment model, and values for several tissues were compared using Blood-IF as the gold standard. On comparing all tissues, the correlation between blood flow obtained with the invasive Blood-IF and both SUV-IF and BSA-IF was significant (R2=0.785 with P<0.001 and R2=0.813 with P<0.001, respectively). In individual tissues, the performance of the two noninvasive methods was most reliable in resting muscle and slightly less reliable in tumour and cerebellar regions. In these two tissues, only BSA-IF showed a significant correlation with Blood-IF (R2=0.307 with P=0.032 in tumours and R2=0.398 with P<0.007 in the cerebellum). The BSA-based noninvasive method enables clinically relevant delineation between areas of low and high blood flow in tumours. The blood flow of low-perfusion tissues can be reliably quantified using either of the evaluated noninvasive methods.

Phenotypic variability in a family with capillary malformations caused by a mutation in the RASA1 gene

Hereditary capillary malformations are known to be caused by mutations in the RASA1 gene. The associated phenotype is still subject of debate. The purpose of this study was to conduct a RASA1 mutation analysis in the family that led to the initial discovery of the 5q locus, and to delineate the associated phenotype. A novel truncating mutation was identified in all clinically affected individuals and in none of the unaffected members. The associated phenotype was widely variable; all individuals had multifocal CM with at least one area of high flow. Various additional features were observed, some previously reported and others novel, including limb overgrowth, varicosities, possible lymphatic malformations, localized hyperhidrosis and exercise induced redness. The cause of this wide intramutational phenotypic variability remains to be elucidated.

Influences of wave fetch, tidal flow and ocean colour on subtidal rocky communities

Community assemblages on subtidal rock change markedly along gradients of wave energy, tidal flow, and turbidity. The importance of these assemblages for rare and delicate spe- cies, for shellfish, as nursery areas for fish, and for their contribution to ecosystem functioning in coastal areas has prompted much conservation effort in many countries. I applied a rapid method of calculating a large high-resolution (200 m scale) map of wave exposure 40% cover had a median of 22 species. Laminaria hyper- borea, and the most diverse communities, is found in areas of estimated low chlorophyll concen- trations and in the most wave-exposed environments, which are often but not always in areas of high tidal flow.

Green Crab (Carcinus maenas) Foraging Efficiency Reduced by Fast Flows

Predators can strongly influence prey populations and the structure and function of ecosystems, but these effects can be modified by environmental stress. For example, fluid velocity and turbulence can alter the impact of predators by limiting their environmental range and altering their foraging ability. We investigated how hydrodynamics affected the foraging behavior of the green crab (Carcinus maenas), which is invading marine habitats throughout the world. High flow velocities are known to reduce green crab predation rates and our study sought to identify the mechanisms by which flow affects green crabs. We performed a series of experiments with green crabs to determine: 1) if their ability to find prey was altered by flow in the field, 2) how flow velocity influenced their foraging efficiency, and 3) how flow velocity affected their handling time of prey. In a field study, we caught significantly fewer crabs in baited traps at sites with fast versus slow flows even though crabs were more abundant in high flow areas. This finding suggests that higher velocity flows impair the ability of green crabs to locate prey. In laboratory flume assays, green crabs foraged less efficiently when flow velocity was increased. Moreover, green crabs required significantly more time to consume prey in high velocity flows. Our data indicate that flow can impose significant chemosensory and physical constraints on green crabs. Hence, hydrodynamics may strongly influence the role that green crabs and other predators play in rocky intertidal communities.

Lack of Primary Cilia Primes Shear-Induced Endothelial-to-Mesenchymal Transition

Primary cilia are cellular protrusions that serve as mechanosensors for fluid flow. In endothelial cells (ECs), they function by transducing local blood flow information into functional responses, such as nitric oxide production and initiation of gene expression. Cilia are present on ECs in areas of low or disturbed flow and absent in areas of high flow. In the embryonic heart, high-flow regime applies to the endocardial cushion area, and the absence of cilia here coincides with the process of endothelial-to-mesenchymal transition (EndoMT). In this study, we investigated the role of the primary cilium in defining the responses of ECs to fluid shear stress and in EndoMT. Nonciliated mouse embryonic ECs with a mutation in Tg737/Ift88 were used to compare the response to fluid shear stress to that of ciliated ECs. In vitro, nonciliated ECs undergo shear-induced EndoMT, which is accompanied by downregulation of Klf4. This Tgfβ/Alk5-dependent transformation is prevented by blocking Tgfβ signaling, overexpression of Klf4, or rescue of the primary cilium. In the hearts of Tg737(orpk/orpk) embryos, Tgfβ/Alk5 signaling was activated in areas in which ECs would normally be ciliated but now lack cilia because of the mutation. In these areas, ECs show increased Smad2 phosphorylation and expression of α-smooth muscle actin. This study demonstrates the central role of primary cilia in rendering ECs prone to shear-induced activation of Tgfβ/Alk5 signaling and EndoMT and thereby provides a functional link between primary cilia and flow-related endothelial performance.

Aggregations and temporal changes in the activity and bioturbation contribution of the sea cucumber Holothuria whitmaei (Echinodermata: Holothuroidea)

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 415:127-139 (2010) - DOI: https://doi.org/10.3354/meps08685 Aggregations and temporal changes in the activity and bioturbation contribution of the sea cucumber Holothuria whitmaei (Echinodermata: Holothuroidea) Glenn R. Shiell1,2,*, Brenton Knott1 1Animal Biology (MO92), The University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA 6009, Australia 2Present address: Oceanica Consulting Pty. Ltd., PO Box 3172, Broadway, Nedlands, Perth, WA 6009, Australia *Email: glenn.shiell@oceanica.com.au ABSTRACT: The population density, activity and bioturbation contribution of the sea cucumber Holothuria whitmaei was investigated on Ningaloo Reef, Western Australia. Two methods, stratified manta tows and blanket manta tows, recorded population densities between 11.4 and >100 individuals (ind.) ha–1. Further analysis revealed a heterogeneous pattern of distribution, with individuals tending to aggregate (Moran’s I; 0.039; p < 0.05) on the outer reef lagoon and particularly in areas of high flow. Densities within aggregations were up to 7.2 times greater than those obtained after blanket manta tows (17.1 ind. ha–1), and 4.5 to 6.3 times greater than those obtained after traditional stratified manta tows (19.3 to 27.1 ind. ha–1). Behavioural studies, including investigations of activity and bioturbation, were conducted over a 2 yr time frame (2002–2003) incorporating 3 monitoring periods within each year: January, April and August. Rates of activity varied diurnally, increasing between morning and afternoon, and seasonally, increasing in April, relative to January and August. Temporal patterns of feeding were more difficult to characterise; although rates of sediment egestion were in many cases higher in the morning, no conclusive diurnal or seasonal patterns could be established. Subsequent regression analysis, however, did find a significant positive correlation between the distance travelled and the volume of sediment egested. The volume of sediment bioturbated by H. whitmaei at a population level was found to represent only a small fraction of the sediments available (ca. 2 to 14% per annum), even though the contribution per individual was greater than that of smaller sea cucumber species. However, at maximum densities and typical rates of activity, H. whitmeai makes physical contact with approximately 2 times the available coral reef sediments per annum per hectare, simply by crawling. This may represent an important ecological contribution, particularly in light of previously documented links between sea cucumber activity, nutrient recycling and the enhancement of benthic microalgal communities. KEY WORDS: Aggregation · Behavioural activity · Bioturbation · Coral reef lagoon · Densitydependent effects Full text in pdf format PreviousNextCite this article as: Shiell GR, Knott B (2010) Aggregations and temporal changes in the activity and bioturbation contribution of the sea cucumber Holothuria whitmaei (Echinodermata: Holothuroidea). Mar Ecol Prog Ser 415:127-139. https://doi.org/10.3354/meps08685Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 415. Online publication date: September 29, 2010 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2010 Inter-Research.

Heat flow, depth–temperature variations and stored thermal energy for enhanced geothermal systems in Canada

In order to help assessment of enhanced geothermal energy potential in Canada, we constructed a new series of heatflow and depth–temperature distribution maps (down to 10 km). We focus on high-temperature resources (>150 °C) capable of electrical production. Maps presented show large temperature variability, related mainly to heat flow patterns. The highest temperatures occur in western and northern Canada. Here temperatures greater than 150 °C, required for enhanced geothermal systems (EGS), can be reached at reasonable drilling depths of <5 km. Heat flow, by itself however, is not a sufficient tool to predict areas of high energy content. A combination of thick low thermal conductivity sedimentary blankets and moderate to high heat flow areas can generate targets that are as favorable as regions with high conductivity and high heat flow. Some moderate heat flow areas in the deeper parts of the Western Canada Sedimentary Basin have heat content comparable to high heat flow zones of the the Canadian Cordillera. The magnitude of in-place thermal energy available for future heat ‘mining/farming’ was esitmated throughout Canada by calculating heat released through cooling a defined rock volume through a fixed temperature change. These estimates show the first-order appoximation of available geothermal heat content. The fraction of true heat energy available will be as low as 0.02 of these values. However, even this more limited energy production could be large enough to be a considerable future renewable energy resource for Canada.

Computational modeling of flow-induced shear stresses within 3D salt-leached porous scaffolds imaged via micro-CT

Flow-induced shear stresses have been found to be a stimulatory factor in pre-osteoblastic cells seeded in 3D porous scaffolds and cultured under continuous flow perfusion. However, due to the complex internal structure of porous scaffolds, analytical estimation of the local shear forces is impractical. The primary goal of this work is to investigate the shear stress distributions within Poly( l-lactic acid) scaffolds via computation. Scaffolds used in this study are prepared via salt leeching with various geometric characteristics (80–95% porosity and 215–402.5 μm average pore size). High resolution micro-computed tomography is used to obtain their 3D structure. Flow of osteogenic media through the scaffolds is modeled via lattice Boltzmann method. It is found that the surface stress distributions within the scaffolds are characterized by long tails to the right (a positive skewness). Their shape is not strongly dependent on the scaffold manufacturing parameters, but the magnitudes of the stresses are. Correlations are prepared for the estimation of the average surface shear stress experienced by the cells within the scaffolds and of the probability density function of the surface stresses. Though the manufacturing technique does not appear to affect the shape of the shear stress distributions, presence of manufacturing defects is found to be significant: defects create areas of high flow and high stress along their periphery. The results of this study are applicable to other polymer systems provided that they are manufactured by a similar salt leeching technique, while the imaging/modeling approach is applicable to all scaffolds relevant to tissue engineering.

Correlations of Seismicity Patterns in Southern California with Surface Heat Flow Data

We investigate the relations between properties of seismicity patterns in Southern California and the surface heat flow using a relocated earthquake catalog. We first search for earthquake sequences that are well separated in time and space from other seismicity and then determine the epidemic type aftershock sequence (ETAS) model parameters for the sequences with a sufficient number of events. We focus on the productivity parameter α of the ETAS model that quantifies the relative efficiency of an earthquake with magnitude M to produce aftershocks. By stacking sequences with relatively small and relatively large α values separately, we observed clear differences between the two groups. Sequences with a smaller α have a relatively large number of foreshocks and relatively small number of after- shocks. In contrast, more typical sequences with larger α have relatively few fore- shocks and larger number of aftershocks. The stacked premainshock activity for the more typical latter sequences has a clear increase in the day before the occurrence of the main event. The spatial distribution of the α values correlates well with the surface heat flow: areas of high heat flow are characterized by relatively small α, indicating that in such regions the swarm-type earthquake activity is more common. Our results are compatible with a damage rheology model that predicts swarm-type seismic activity in areas with relatively high heat flow and more typical foreshock- mainshock-aftershock sequences in regions with normal or low surface heat flow. The high variability of α in regions with either high or low heat flow values indicates that at local scales additional factors (e.g., fluid content and rock type) may influence the seismicity generation process.

Ecology of small neritic fishes in the western Gulf of Alaska. I. Geographic distribution in relation to prey density and the physical environment

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 392:223-237 (2009) - DOI: https://doi.org/10.3354/meps08160 Ecology of small neritic fishes in the western Gulf of Alaska. I. Geographic distribution in relation to prey density and the physical environment Matthew T. Wilson* Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 7600 Sand Point Way NE, Seattle, Washington 98115, USA *Email: matt.wilson@noaa.gov ABSTRACT: Physical heterogeneity affects the geographic structure of coastal ocean ecosystems by influencing the spatial distribution of zooplankton and their nektonic predators. This was examined in the western Gulf of Alaska (GOA) during late summer (2000, 2001, and 2003) when seasonal increases in the Alaska Coastal Current flow and additions of Age-0 fishes to the nektonic community of small neritic fishes coincided with declining zooplankton abundance. The 48-site sampling grid was divided into 5 meso-scale areas based on physical condition (temperature, salinity, net current velocity). Larval crabs and fishes, and krill were the only zooplankton taxa for which the population density consistently differed by area regardless of diel period (day, night) or year. Larval crabs and fishes concentrated near shore in warm, low-salinity water. Krill concentrated in high-flow areas, which, over the shelf, were associated with sea valleys. Dominant fishes were walleye pollock Theragra chalcogramma, capelin Mallotus villosus, and eulachon Thaleichthys pacificus. Few fish occurred beyond the shelf in the cold, swift-flowing Alaskan Stream boundary current. Over the shelf, Age-1+ walleye pollock and eulachon aggregated with krill in high-flow areas. Smaller fishes (Age-0 walleye pollock and capelin) were more variably distributed, and were not well associated with taxon-specific zooplankton densities. Thus, relatively high flow in proximity to sea valleys was associated with concentrations of krill and fishes that presumably were able to efficiently forage on krill in high-flow areas. The year-to-year consistency in patterns is a noteworthy indication that geographic structure in the coastal GOA ecosystem may resist climate forcing. KEY WORDS: Walleye pollock · Capelin · Eulachon · Zooplankton · Population density · Body size Full text in pdf format PreviousNextCite this article as: Wilson MT (2009) Ecology of small neritic fishes in the western Gulf of Alaska. I. Geographic distribution in relation to prey density and the physical environment. Mar Ecol Prog Ser 392:223-237. https://doi.org/10.3354/meps08160Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 392. Online publication date: October 19, 2009 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2009 Inter-Research.

Ecology of small neritic fishes in the western Gulf of Alaska. II. Consumption of krill in relation to krill standing stock and the physical environment

Krill (Euphausiacea) is a patchily distributed taxon whose availability may limit neritic fishes in temperate oceans. In the western Gulf of Alaska, krill-fish aggregations were associated with high-flow areas over the shelf. We examined fish impacts on krill standing stocks in areas of dif- ferent temperature, salinity, and net current velocity. Samples were collected during September 2000, 2001, and 2003 over a 48-site grid within a known walleye pollock nursery. Krill were a dietary staple of the dominant fishes: walleye pollock Theragra chalcogramma, capelin Mallotus villosus, and eulachon Thaleichthys pacificus, but their proportion in diets varied by predator species and predator length. Predators daily consumed ≤12% of standing stocks; thus, krill appeared to be amply available. However, the krill consumed by eulachon and large (>120 mm) walleye pollock were, on average, large compared to krill in plankton samples; therefore, standing stock sizes might have been overestimated by including small krill. A compensatory response in consumption occurred dur- ing 2001 in proximity to the Shelikof sea valley due to increased per capita predation rates and local concentration of Age-1+ walleye pollock and eulachon. High abundance of krill in 2001 was associ- ated with high ocean current flow. No compensatory response was observed where local standing stocks were dominated by small krill. Thus, apparent bottom-up influences of ocean currents on krill abundance in neritic areas can be partly compensated by localized top-down predation from nek- tonic fishes having prey size preferences that match available prey sizes.

Using Spatial Features to Review Application, Effectiveness, and Compliance of Forestry Best Management Practices in West Virginia

The application, effectiveness, and compliance of forestry best management practices (BMPs) were assessed based on 33 randomly selected sites with streamside management zones (SMZs) in West Virginia. Application of BMPs was assessed based upon the methods and techniques of applying the BMP, while compliance was assessed based on the presence of required BMPs. Effectiveness was determined based upon the durability and longevity of an applied BMP. A series of 12 checklists were used to examine 29 BMPs on haul roads, skid trails, landings, and in SMZs. Spatial data, soil, stream type, and population density were also collected for the sites to identify how these spatial attributes affect BMP application, effectiveness, and compliance. Results indicated that higher levels of application, effectiveness, and compliance were found on sites with either intermittent or ephemeral streams, wider SMZs, or low soil moisture index; no significant differences were presented in BMP application, effectiveness, and compliance among stream type, SMZ width, soil series, moisture index, and population category. Road and landing layouts located outside of high water cumulative flow areas also contributed to higher rates of BMP application, effectiveness, and compliance, which substantiated the importance of pre-harvest planning.

Anatomo-pathological analysis after CoreValve Revalving system implantation

Significant technological improvements have made percutaneous aortic valve replacement (PAVR) simpler and safer, but the behaviour of the implanted valve over time remains unknown. We report the anatomo-pathological analysis of patients who died at different time intervals post PAVR with the CoreValve Revalving System. In our early experience, 21 patients underwent CoreValve implantation between 12/2005 and 02/2007. Among the 11 deaths at one year follow-up, four patients had an autopsy with macro and microscopic analysis. The device was divided in three parts during pathological assessment: the lower portion (area 1), the leaflets (area 2) and the upper part (area 3). The CoreValves were implanted for 3, 13, 104 and 350 days. Gross examination showed neointimal tissue covering most of the frame struts in contact with the aortic wall, but areas of high velocity blood flow were bare. Histopathology examination demonstrated fibrin deposition and inflammatory response early after valve implantation, followed by neointimal coverage with progressive regression of the inflammatory response over time. While waiting for results of longer term PAVR echocardiographic follow-up, the anatomic assessment is encouraging with neointimal coverage of the native valve site and no excessive pannus formation occurring over the valve leaflets.

Bioimprovement of Soils for Highway Applications Using Rolled Erosion Control Products

Highway departments are regularly faced with minimizing the soil erosion from highway construction sites. One of the most effective ways of minimizing soil erosion is to provide ground cover that can intercept raindrops. Although bioimprovement (vegetation) is commonly used, it is difficult to establish on steep slopes and in high flow areas, and to a suitable density to provide adequate ground coverage. As a result, rolled erosion control products (RECPs) are often used to provide immediate ground cover protection for soils, enhance the growth of vegetation, and reinforce vegetation once it is established. The success of RECPs has led to development of a wide variety of different RECPs that can vary significantly in basic properties and performance. Although many studies have been published documenting the successful use of RECPs, limited work has been done to compare the rainsplash erosion performance of different types of vegetated RECPs and their mechanisms in minimizing soil erosion. On the basis of results of more than 200 laboratory rainsplash erosion tests on 13 different types of vegetated RECPs, it was found that the use of vegetated RECPs can significantly reduce soil losses on bare soil slopes by an average of 95% to 100% in comparison with bare soil alone. Vegetation improved the performance of the RECPs alone by an average of 54% and 95%. Care must be taken in the design and selection of RECPs to optimize their performance.

Outdoor and Indoor Respirable Air Particulate Concentrations in Differing Urban Traffic Microenvironments

To study the adverse health effects associated with ambient respirable particulates it is necessary to assess population exposure. However, measurements are usually carried out by fixed-site air monitoring units and do not take into consideration the range of urban microenvironments. In particular, vehicular emissions are a major source of particulates in cities and it is therefore necessary to consider traffic density when investigating the adverse health effects of air particulates. This study assessed both PM5 and total particle number (TPN) in areas of high and low traffic flow within the city of Cardiff, UK. Daytime measurements were made outdoors throughout the period January 2004–June 2005. Simultaneous indoor measurements were made in 73 participating households in areas of high traffic flow (exposed) and 50 households in areas of low traffic flow (controls). The median outdoor PM5 concentration in the exposed area (16.7 μg cm−3) was 45% significantly higher than that in the unexposed area (11.5 μg cm−3) and the median TPN in the exposed area (18,130 particles cm−3) was almost double that in the unexposed area (9951 particles cm−3). The median indoor concentration of PM5 in the exposed area (13.2 μg cm−3) was also 40% significantly higher than that in the unexposed area (9.4 μg cm−3), but there was almost no difference in indoor median TPN between the two areas: 8999 particles cm−3 and 8549 particles cm−3, respectively. The observed differences in respirable particles between areas of high and low traffic flow underline the importance of obtaining exposure measurements in microenvironments.