Sample records for laboratory flume studies

  1. Aids in designing laboratory flumes

    USGS Publications Warehouse

    Williams, Garnett P.

    1971-01-01

    The upsurge of interest in our environment has caused research and instruction in the flow of water along open channels to become increasingly popular in universities and institutes. This, in turn, has brought a greater demand for properly-designed laboratory flumes. Whatever the reason for your interest, designing and building the flume will take a little preparation. You may choose a pattern exactly like a previous design, or you may follow the more time-consuming method of studying several existing flumes and combine the most desirable features of each.

  2. Application of Structure-from-Motion photogrammetry in laboratory flumes

    NASA Astrophysics Data System (ADS)

    Morgan, Jacob A.; Brogan, Daniel J.; Nelson, Peter A.

    2017-01-01

    Structure-from-Motion (SfM) photogrammetry has become widely used for topographic data collection in field and laboratory studies. However, the relative performance of SfM against other methods of topographic measurement in a laboratory flume environment has not been systematically evaluated, and there is a general lack of guidelines for SfM application in flume settings. As the use of SfM in laboratory flume settings becomes more widespread, it is increasingly critical to develop an understanding of how to acquire and process SfM data for a given flume size and sediment characteristics. In this study, we: (1) compare the resolution and accuracy of SfM topographic measurements to terrestrial laser scanning (TLS) measurements in laboratory flumes of varying physical dimensions containing sediments of varying grain sizes; (2) explore the effects of different image acquisition protocols and data processing methods on the resolution and accuracy of topographic data derived from SfM techniques; and (3) provide general guidance for image acquisition and processing for SfM applications in laboratory flumes. To investigate the effects of flume size, sediment size, and photo overlap on the density and accuracy of SfM data, we collected topographic data using both TLS and SfM in five flumes with widths ranging from 0.22 to 6.71 m, lengths ranging from 9.14 to 30.48 m, and median sediment sizes ranging from 0.2 to 31 mm. Acquisition time, image overlap, point density, elevation data, and computed roughness parameters were compared to evaluate the performance of SfM against TLS. We also collected images of a pan of gravel where we varied the distance and angle between the camera and sediment in order to explore how photo acquisition affects the ability to capture grain-scale microtopographic features in SfM-derived point clouds. A variety of image combinations and SfM software package settings were also investigated to determine optimal processing techniques. Results from this

  3. HYDRAULIC CHARACTERISTICS OF SEWER SEDIMENT GATE FLUSHING TANKS: LABORATORY FLUME STUDIES

    EPA Science Inventory

    The objective of this study was to test the performance of gate flushing tanks, simulated in a laboratory flume, to remove sediments from combined sewers and storage tanks. A significant amount of sediment/debris/sludge may accumulate at the bottom of a sewer during dry weather o...

  4. HYDRAULIC CHARACTERISTICS OF SEWER SEDIMENT GATE-FLUSHING TANKS: LABORATORY FLUME STUDIES

    EPA Science Inventory

    The objective of this study was to test the performance of gate-flushing tanks, simulated in a laboratory flume, to remove sediments from combined sewers and storage tanks. A significant amount of sediment/debris/sludge may accumulate at the bottom of a sewer during dry weather o...

  5. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jacobson, Paul T.; Amaral, Stephen V.; Castro-Santos, Theodore

    This collection of three reports describes desktop and laboratory flume studies that provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river environments. Behavioral responses to turbine exposure also are investigated to support assessment of the potential for disruptions to upstream and downstream movements of fish. The studies: (1) conducted an assessment of potential injury mechanisms using available data from studies with conventional hydro turbines; (2) developed theoretical models for predicting blade strike probabilities and mortality rates; and (3) performed flume testing with threemore » turbine designs and several fish species and size groups in two laboratory flumes to estimate survival rates and document fish behavior. The project yielded three reports which this document comprises. The three constituent documents are addressed individually below Fish Passage Through Turbines: Application of Conventional Hydropower Data to Hydrokinetic Technologies Fish passing through the blade sweep of a hydrokinetic turbine experience a much less harsh physical environment than do fish entrained through conventional hydro turbines. The design and operation of conventional turbines results in high flow velocities, abrupt changes in flow direction, relatively high runner rotational and blade speeds, rapid and significant changes in pressure, and the need for various structures throughout the turbine passageway that can be impacted by fish. These conditions generally do not occur or are not significant factors for hydrokinetic turbines. Furthermore, compared to conventional hydro turbines, hydrokinetic turbines typically produce relatively minor changes in shear, turbulence, and pressure levels from ambient conditions in the surrounding environment. Injuries and mortality from mechanical injuries will be less as well, mainly due to low rotational

  6. Self-Formed Meanders (With Cutoffs) in a Laboratory Flume

    NASA Astrophysics Data System (ADS)

    Braudrick, C. A.; Leverich, G. T.; Sklar, L. S.; Dietrich, W. E.

    2005-12-01

    The development of a mechanistic understanding of channel geometry and morphodynamics has been inhibited by the inability to create self-formed, freely meandering, single thread channels in a laboratory flume. By being able to reliably generate such channels, studies of the influence of sediment supply and flow dynamics as well as bank strength on channel morphology can be experimentally explored. We have found that the key experimental controls are: 1) ratio of bank strength to boundary shear stress exerted on the bank; 2) bedload and suspended load rates; and 3) variable flow discharge. We have been able to create meandering channels in a sand bedded laboratory flume using alfalfa sprouts. The alfalfa sprouts decrease the bank erosion rate so that bank erosion would occur at approximately the same pace as bar growth. The addition of coarse suspended load was necessary to cause deposition on bars to grow to the floodplain height. The sprouts contributed to deposition by creating a rough floodplain surface. Steady discharge failed to produced meandering, apparently due to the lack of suspended load deposition on the bar surface. The channels were created in a 3.6-m wide and 6.1-m long flume with an adjustable slope set at 0.01. We introduced both bedload (sand) and suspended load (crushed silica) into the top of the flume, which has an initial channel with either one or two bends carved into the floodplain. Runs lasted between 1 and 4 hours and occurred once per week. Alfalfa seeds were spread evenly outside the low flow channel following each run and are allowed to grow between runs. With the same material and flow conditions, the channel rapidly braided without the alfalfa sprouts. Braided was also favored under steady flow conditions. Under dynamic flows with banks strengthened by sprouts, the resulting experimental channels had many of the features observed in meandering streams such as oxbow lakes and meander cutoffs. The cutoffs occurred during overbank flows

  7. View of the Flume above Sally May Siphon ("Steel Flume ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of the Flume above Sally May Siphon ("Steel Flume on Trestles" in narrative inventory). At far end is Flume Tunnel No. 3 (AZ-65-T) through Purple Mountain. Looking southwest - Childs-Irving Hydroelectric Project, Childs System, Steel Flume on Trestles, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  8. View of Flume Bridge #4 showing flume and trestles. Looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Flume Bridge #4 showing flume and trestles. Looking northeast - Childs-Irving Hydroelectric Project, Childs System, Flume Bridge No. 4, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  9. View of Flume Tunnel #3 through Purple Mountain, showing flume ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Flume Tunnel #3 through Purple Mountain, showing flume entering into the tunnel. Looking south - Childs-Irving Hydroelectric Project, Childs System, Flume Tunnel No. 3, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  10. Creating self-formed meandering channels in laboratory flumes (Invited)

    NASA Astrophysics Data System (ADS)

    Braudrick, C. A.

    2009-12-01

    Our ability to construct predictive numerical models for meandering rivers is hampered by the inability to create meandering channels in the laboratory where individual variables can be isolated and controlled. Typically, experimental channels braid, straighten, or cease migration once they develop curvature. By using alfalfa sprouts to provide bank strength and fine sediment to attach point bars to the floodplain, we have successfully created and maintained meandering morphology in a laboratory flume. The 6.1 by 17 m flume has a floodplain slope of approximately 0.005 with a sandy bed and banks that scales as a gravel bed river. The alfalfa sprouts slow bank erosion allowing time for the bars to create new floodplain deposits. The sprouts also increase floodplain roughness, armor new bar deposits, and promote deposition of overbank sediment. The fine sediment, a lightweight plastic that scaled as sand, was crucial for blocking chutes formed between the bar and the floodplain, isolating cut-off channels from the main flow, and creating levees. During this 136-hour long experiment, the channel width stabilized as the channel migrated across the floodplain, and the curvature was recreated following cutoffs. Although the sinuosity (about 1.2) was low relative to meandering channels observed in the field, the spacing of bends was within the upper bounds of field examples. Subsequent experiments with higher bank strength had more limited chute development were able to generate a sinuosity of about 1.4. Scaling analysis indicates that the bank migration rates in the lower sinuosity experiment were approximately 10 times faster than migration rates in the field. A particular challenge in these experiments is maintaining a healthy alfalfa crop. After 15-20 hours of flood flows, the alfalfa begins to die off and new emergent bars need to be seeded. It then takes about 7 days for the alfalfa to grow to the size used in these experiments. The 15-20 hours scale to about one

  11. Implications of flume slope on discharge estimates from 0.762-meter H flumes used in edge-of-field monitoring

    USGS Publications Warehouse

    Komiskey, Matthew J.; Stuntebeck, Todd D.; Cox, Amanda L.; Frame, Dennis R.

    2013-01-01

    The effects of longitudinal slope on the estimation of discharge in a 0.762-meter (m) (depth at flume entrance) H flume were tested under controlled conditions with slopes from −8 to +8 percent and discharges from 1.2 to 323 liters per second. Compared to the stage-discharge rating for a longitudinal flume slope of zero, computed discharges were negatively biased (maximum −31 percent) when the flume was sloped downward from the front (entrance) to the back (exit), and positively biased (maximum 44 percent) when the flume was sloped upward. Biases increased with greater flume slopes and with lower discharges. A linear empirical relation was developed to compute a corrected reference stage for a 0.762-m H flume using measured stage and flume slope. The reference stage was then used to determine a corrected discharge from the stage-discharge rating. A dimensionally homogeneous correction equation also was developed, which could theoretically be used for all standard H-flume sizes. Use of the corrected discharge computation method for a sloped H flume was determined to have errors ranging from −2.2 to 4.6 percent compared to the H-flume measured discharge at a level position. These results emphasize the importance of the measurement of and the correction for flume slope during an edge-of-field study if the most accurate discharge estimates are desired.

  12. Determination of Optimum Sanitizer Levels for Prevention of Salmonella Cross-Contamination of Mature Round Tomatoes in a Laboratory Model Flume System.

    PubMed

    Sreedharan, Aswathy; Li, You; De, Jaysankar; Gutierrez, Alan; Silverberg, Rachael; Schneider, Keith R

    2017-09-01

    Salmonella has been reported to be involved in several foodborne illness outbreaks, many of which resulted from consumption of raw tomatoes. This research aimed to optimize and evaluate the concentration of free chlorine (hypochlorous acid [HOCl]) used as a sanitizer to prevent cross-contamination of tomatoes inoculated with a cocktail of five rifampin-resistant Salmonella enterica serovars in a laboratory-based model flume system. Organic load, prepared using sterilized Scotts Premium Topsoil, was added in different quantities to the flume wash water to simulate real-world packinghouse conditions. In a typical packinghouse operation utilizing a recirculating flume system, the organic matter washed from tomato surfaces accumulates over time. In this study, different concentrations (0, 25, 50, 75, and 100 ppm) of HOCl were used as sanitizers under three organic load conditions (0, 650, and 1,000 mg/L chemical oxygen demand). Results showed that 100 ppm of HOCl was necessary to prevent Salmonella cross-contamination of uninoculated tomatoes in the model flume system in the presence of organic loading. Also, when treated with 100 ppm of HOCl, Salmonella levels were reduced by >4.5 log CFU per tomato from inoculated tomatoes in the presence of organic load. At 75 ppm of HOCl, Salmonella cross-contamination was prevented, but only in the absence of organic loading. In studies in which plate counts were negative, whole tomato enrichment studies were performed. No cross-contamination of uninoculated tomatoes was recorded when 100 ppm of HOCl was used, even in the presence of high organic load (1,000 mg/L chemical oxygen demand). Although sanitizer application reduces contamination on tomato surfaces, the primary function of sanitizers in the wash water is to prevent cross-contamination.

  13. Use of flumes in measuring discharge

    USGS Publications Warehouse

    Kilpatrick, F.A.; Schneider, V.R.

    1983-01-01

    Flumes for measuring discharge are usually of two general groups-critical-flow flumes and supercritical-flow flumes. In this chapter, the underlying design principles for each group are discussed; the most commonly used flumes are described and their discharge ratings presented. There is also discussion of considerations in choosing and fitting the appropriate flume for a given situation as well as flume construction techniques and operational experiences.

  14. Transport mechanisms of Silver Nanoparticles by runoff - A Flume Experiment

    NASA Astrophysics Data System (ADS)

    Mahdi Mahdi, Karrar NM; Commelin, Meindert; Peters, Ruud J. B.; Baartman, Jantiene E. M.; Ritsema, Coen; Geissen, Violette

    2017-04-01

    Silver Nanoparticles (AgNPs) are being used in many products as it has unique antimicrobial-biocidal properties. Through leaching, these particles will reach the soil environment which may affect soil organisms and disrupt plants. This work aims to study the potential transport of AgNPs with water and sediment over the soil surface due to soil erosion by water. This was done in a laboratory setting, using a rainfall simulator and flume. Low AgNPs concentration (50 μg.kg-1) was applied to two soil-flumes with slopes of 20% and 10%. The rainfall was applied in four events of 15 min each with the total amount of rainfall was 15mm in each event. After applying the rainfall, different samples were collected; soil clusters, background (BS) and surface sediments (Sf), from the flume surface, and, Runoff sediments (RS) and water (RW) was collected from the outlet. The results showed that AgNPs were detected in all samples collected, however, AgNPs concentration varied according samples type (soil or water), time of collection (for runoff water and sediment) and the slope of the soil flume. Further, the higher AgNPs concentrations were detected in the background soil (BS); as the BS samples have more finer parts (silt and clay). The AgNPs concentration in the runoff sediments increased with subsequent applied rain events. In addition to that, increasing the slope of the flume from 10% to 20% increased the total AgNPs transported with the runoff sediments by a factor 1.5. The study confirms that AgNPs can be transported over the soil surface by both runoff water and sediments due to erosion.

  15. Bioturbation, advection, and diffusion of a conserved tracer in a laboratory flume

    NASA Astrophysics Data System (ADS)

    Work, P. A.; Moore, P. R.; Reible, D. D.

    2002-06-01

    Laboratory experiments indicating the relative influences of advection, diffusion, and bioturbation on transport of NaCl tracer between a stream and streambed are described. Data were collected in a recirculating flume housing a box filled with test sediments. Peclet numbers ranged from 0 to 1.5. Sediment components included a medium sand (d50 = 0.31 mm), kaolinite, and topsoil. Lumbriculus variegatus were introduced as bioturbators. Conductivity probes were employed to document the flux of the tracer solution out of the bed. Measurements are compared to one-dimensional effective diffusion models assuming one or two horizontal sediment layers. These simple models provide a good indication of tracer half-life in the bed if a suitable effective diffusion coefficient is chosen but underpredict initial flux and overpredict flux at long times. Organism activity was limited to the upper reaches of the sediment test box but eventually exerts a secondary influence on flux from deeper regions.

  16. Application of a Line Laser Scanner for Bed Form Tracking in a Laboratory Flume

    NASA Astrophysics Data System (ADS)

    de Ruijsscher, T. V.; Hoitink, A. J. F.; Dinnissen, S.; Vermeulen, B.; Hazenberg, P.

    2018-03-01

    A new measurement method for continuous detection of bed forms in movable bed laboratory experiments is presented and tested. The device consists of a line laser coupled to a 3-D camera, which makes use of triangulation. This allows to measure bed forms during morphodynamic experiments, without removing the water from the flume. A correction is applied for the effect of laser refraction at the air-water interface. We conclude that the absolute measurement error increases with increasing flow velocity, its standard deviation increases with water depth and flow velocity, and the percentage of missing values increases with water depth. Although 71% of the data is lost in a pilot moving bed experiment with sand, still high agreement between flowing water and dry bed measurements is found when a robust LOcally weighted regrESSion (LOESS) procedure is applied. This is promising for bed form tracking applications in laboratory experiments, especially when lightweight sediments like polystyrene are used, which require smaller flow velocities to achieve dynamic similarity to the prototype. This is confirmed in a moving bed experiment with polystyrene.

  17. Aggression and feeding of hatchery-reared and naturally reared steelhead (Oncorhynchus mykiss) fry in a laboratory flume and a comparison with observations in natural streams

    USGS Publications Warehouse

    Riley, S.C.; Tatara, C.P.; Scheurer, J.A.

    2005-01-01

    We quantified the aggression and feeding of naturally reared steelhead (Oncorhynchus mykiss) fry stocked into a laboratory flume with naturally reared fry or hatchery-reared fry from conventional and enriched rearing environments at three densities in the presence and absence of predators, and compared the aggression and feeding observed in the flume to that observed in two streams. Steelhead fry attack rate increased with density and was reduced in the presence of predators, but was not affected by rearing treatment. Threat rate appeared to increase with density and was significantly affected by rearing treatment combination, but was not significantly affected by predator presence. Feeding rate was not affected by density or rearing treatment, but was reduced in the presence of predators. The rate of aggression by steelhead fry in two streams was lower than that observed in the laboratory and did not increase with density. Rates of aggression and feeding of hatchery-reared and wild steelhead fry were not significantly different in the streams. Overall, we found no evidence that hatchery rearing environments caused higher aggression in steelhead fry. Laboratory observations of salmonid aggression, particularly at high density, may not reflect aggression levels in the wild. ?? 2005 NRC.

  18. Modelling landscape evolution at the flume scale

    NASA Astrophysics Data System (ADS)

    Cheraghi, Mohsen; Rinaldo, Andrea; Sander, Graham C.; Barry, D. Andrew

    2017-04-01

    The ability of a large-scale Landscape Evolution Model (LEM) to simulate the soil surface morphological evolution as observed in a laboratory flume (1-m × 2-m surface area) was investigated. The soil surface was initially smooth, and was subjected to heterogeneous rainfall in an experiment designed to avoid rill formation. Low-cohesive fine sand was placed in the flume while the slope and relief height were 5 % and 20 cm, respectively. Non-uniform rainfall with an average intensity of 85 mm h-1 and a standard deviation of 26 % was applied to the sediment surface for 16 h. We hypothesized that the complex overland water flow can be represented by a drainage discharge network, which was calculated via the micro-morphology and the rainfall distribution. Measurements included high resolution Digital Elevation Models that were captured at intervals during the experiment. The calibrated LEM captured the migration of the main flow path from the low precipitation area into the high precipitation area. Furthermore, both model and experiment showed a steep transition zone in soil elevation that moved upstream during the experiment. We conclude that the LEM is applicable under non-uniform rainfall and in the absence of surface incisions, thereby extending its applicability beyond that shown in previous applications. Keywords: Numerical simulation, Flume experiment, Particle Swarm Optimization, Sediment transport, River network evolution model.

  19. Use of flumes in metering discharge at gaging stations

    USGS Publications Warehouse

    Kilpatrick, F.A.; Schneider, V.R.

    1982-01-01

    Flumes for metering discharge are usually of two general types--critical-flow flumes and supercritical-flow flumes. In this report the principles underlying the design of each are discussed, the most commonly used flumes of each of the two types are described, and discharge ratings for each are presented. Considerations in choosing and fitting the appropriate flume for a given situation are discussed along with construction techniques and operational experiences.

  20. Closed flume inlet efficiency.

    DOT National Transportation Integrated Search

    2014-04-01

    The goal of the present study was to determine the efficiency of a specific culvert geometry, labeled as : Index 216 Closed Flume Inlet (CFI) in the FDOTs Design Standards, and to determine if geometric changes : affect the efficiency of the curre...

  1. Flume experimentation and simulation of bedrock channel processes

    NASA Astrophysics Data System (ADS)

    Thompson, Douglas; Wohl, Ellen

    Flume experiments can provide cost effective, physically manageable miniature representations of complex bedrock channels. The inherent change in scale in such experiments requires a corresponding change in the scale of the forces represented in the flume system. Three modeling approaches have been developed that either ignore the scaling effects, utilize the change in scaled forces, or assume similarity of process between scales. An understanding of the nonlinear influence of a change in scale on all the forces involved is important to correctly analyze model results. Similarly, proper design and operation of flume experiments requires knowledge of the fundamental components of flume systems. Entrance and exit regions of the flume are used to provide good experimental conditions in the measurement region of the flume where data are collected. To insure reproducibility, large-scale turbulence must be removed in the head of the flume and velocity profiles must become fully developed in the entrance region. Water-surface slope and flow acceleration effects from downstream water-depth control must also be isolated in the exit region. Statistical design and development of representative channel substrate also influence model results in these systems. With proper experimental design, flumes may be used to investigate bedrock channel hydraulics, sediment-transport relations, and morphologic evolution. In particular, researchers have successfully used flume experiments to demonstrate the importance of turbulence and substrate characteristics in bedrock channel evolution. Turbulence often operates in a self perpetuating fashion, can erode bedrock walls with clear water and increase the mobility of sediment particles. Bedrock substrate influences channel evolution by offering varying resistance to erosion, controlling the location or type of incision and modifying the local influence of turbulence. An increased usage of scaled flume models may help to clarify the remaining

  2. Monitoring of surface velocity of hyper-concentrated flow in a laboratory flume by means of fully-digital PIV

    NASA Astrophysics Data System (ADS)

    Termini, Donatella; Di Leonardo, Alice

    2016-04-01

    High flow conditions, which are generally characterized by high sediment concentrations, do not permit the use of traditional measurement equipment. Traditional techniques usually are based on the intrusive measure of the vertical profile of flow velocity and on the linking of water depth with the discharge through the rating curve. The major disadvantage of these measurement techniques is that they are difficult to use and not safe for operators especially in high flow conditions. The point is that, as literature shows (see as an example Moramarco and Termini, 2015), especially in such conditions, the measurement of surface velocity distribution is important to evaluate the mean flow velocity and, thus, the flow discharge. In the last decade, image-based techniques have been increasingly used for surface velocity measurements (among others Joeau et al., 2008). Experimental program has been recently conducted at the Hydraulic laboratory of the Department of Civil, Environmental, Aerospatial and of Materials Engineering (DICAM) - University of Palermo (Italy) in order to analyze the propagation phenomenon of hyper-concentrated flow in a defense channel. The experimental apparatus includes a high-precision camera and a system allowing the images recording. This paper investigates the utility and the efficiency of the digital image-technique for remote monitoring of surface velocity in hyper-concentrated flow by the aid of data collected during experiments conducted in the laboratory flume. In particular the present paper attention is focused on the estimation procedure of the velocity vectors and on their sensitivity with parameters (number of images, spatial resolution of interrogation area,) of the images processing procedure. References Jodeau M., A. Hauet, A. Paquier, Le Coz J., Dramais G., Application and evaluation of LS-PIV technique for the monitoring of river surface in high flow conditions, Flow Measurements and Instrumentation, Vol.19, No.2, 2008, pp.117

  3. Bioflumology: Microbial mat growth in flumes

    NASA Astrophysics Data System (ADS)

    Airo, A.; Weigert, S.; Beck, C.

    2014-04-01

    The emergence of oxygenic photosynthesis resulted in a transformational change of Earth's geochemical cycles and the subsequent evolution of life. However, it remains vigorously debated when this metabolic ability had evolved in cyanobacteria. This is largely because studies of Archean microfossil morphology, molecular biomarkers, and isotopic characteristics are frequently ambiguous. However, the high degree of morphological similarities between modern photosynthetic and Archean fossil mats has been interpreted to indicate phototactic microbial behavior or oxygenic photosynthesis. In order to better evaluate the relationship between mat morphology and metabolism, we here present a laboratory set-up for conducting month-long experiments in several sterilizable circular flumes designed to allow single-species cyanobacterial growth under adjustable fluid-flow conditions and protected from contamination.

  4. 14. PECOS RIVER FLUME Photographic copy of historic photo, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. PECOS RIVER FLUME - Photographic copy of historic photo, 1890 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico), Stringfellow, Eddy, N.M., photographer 'OLD WOOD FLUME' - Carlsbad Irrigation District, Pecos River Flume, On Main Canal, .5 mile North of Carlsbad, Carlsbad, Eddy County, NM

  5. 15. PECOS RIVER FLUME Photographic copy of historic photo, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. PECOS RIVER FLUME - Photographic copy of historic photo, May 1, 1903 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico), Butler, Carlsbad, photographer. VIEW OF PECOS RIVER FLUME UNDER CONSTRUCTION - Carlsbad Irrigation District, Pecos River Flume, On Main Canal, .5 mile North of Carlsbad, Carlsbad, Eddy County, NM

  6. 38. From hilltop, Route 14, last segment of flume before ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    38. From hilltop, Route 14, last segment of flume before Broughton Lumber Company. Section of flume and broken out section. Columbia River and Oregon in background. West/southwest 240 degrees. - Broughton Flume, Hood River Junction on Columbia River at Washington/Oregon border, Hood, Skamania County, WA

  7. View of Flume Tunnel #5 showing an example of concrete ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Flume Tunnel #5 showing an example of concrete flume covered with concrete slabs as it enters a tunnel under the road (FS 502). Looking southwest - Childs-Irving Hydroelectric Project, Childs System, Flume Tunnel No. 5, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  8. 6. WORKMEN REPLACING STEEL PLATES IN FLUME NO. 10, ABOVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. WORKMEN REPLACING STEEL PLATES IN FLUME NO. 10, ABOVE SAR-1. FLUME FOR SAR-3 WAS REBUILT AT THE SAME TIME. SCE negative no. 11776, May 1, 1926. Photograph by G. Haven Bishop. - Santa Ana River Hydroelectric System, Flumes & Tunnels below Sandbox, Redlands, San Bernardino County, CA

  9. SEWER SEDIMENT GATE AND VACUUM FLUSHING TANKS: LABORATORY FLUME STUDIES

    EPA Science Inventory

    The objective of this study was to test the performance of a traditional gate-flushing device and a newly designed vacuum-flushing device in removing sediments from combined sewers and CSO storage tanks. A laboratory hydraulic flune was used to simulate a reach of sewer or storag...

  10. Determination of Adsorption Capacity and Kinetics of Amidoxime-Based Uranium Adsorbent Braided Material in Unfiltered Seawater Using a Flume Exposure System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gill, Gary A.; Kuo, Li-Jung; Strivens, Jonathan E.

    PNNL has developed a recirculating flume system for exposing braided adsorbent material to natural seawater under realistic temperature and flow-rate exposure conditions. The flumes are constructed of transparent acrylic material; they allow external light to pass into the flumes and permit photosynthetic growth of naturally present marine organisms (biofouling). Because the system consists of two flumes, replicate experiments can be conducted in which one of the flumes can be manipulated relative to the other. For example, one flume can be darkened to eliminate light exposure by placing a black tarp over the flume such that dark/light experiments can be conducted.more » Alternatively, two different braided adsorbents can be exposed simultaneously with no potential cross contamination issues. This report describes the first use of the PNNL flume system to study the impact of biofouling on adsorbent capacity. Experiments were conducted with the ORNL AI8 braided adsorbent material in light-exposed and darkened flumes for a 42-day exposure experiment. The major objective of this effort is to develop a system for the exposure of braided adsorbent material to unfiltered seawater, and to demonstrate the system by evaluating the performance of adsorption material when it is exposed to natural marine biofouling as it would be when the technology is used in the marine environment. Exposures of amidoxime-based polymeric braid adsorbents prepared by Oak Ridge Natural Laboratory (ORNL) were exposed to ambient seawater at 20°C in a flume system. Adsorption kinetics and adsorption capacity were assessed using time series determinations of uranium adsorption and one-site ligand saturation modeling. Biofouling in sunlight surface seawater has the potential to significantly add substantial biogenic mass to adsorption material when it is exposed for periods greater than 21 days. The observed biomass increase in the light flume was approximately 80% of the adsorbent mass after 42

  11. 4. THIRD FLUME ABOVE SAR1 FOREBAY, SHOWING TYPICAL CHANGE IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. THIRD FLUME ABOVE SAR-1 FOREBAY, SHOWING TYPICAL CHANGE IN CURVATURE OF METAL SHEETING AS FLUME MEETS TUNNEL AT PORTAL. VIEW TO NORTH. - Santa Ana River Hydroelectric System, Flumes & Tunnels below Sandbox, Redlands, San Bernardino County, CA

  12. Determination of Flow Resistance Coefficient for Vegetation in Open Channel: Laboratory study

    NASA Astrophysics Data System (ADS)

    Aliza Ahmad, Noor; Ali, ZarinaMd; Arish, Nur Aini Mohd; Munirah Mat Daud, Azra; Fatin Amirah Alias, Nur

    2018-04-01

    This study focused on determination of flow resistances coefficient for grass in an open channel. Laboratory works were conducted to examine the effects of varying of roughness elements on the flume to determine flow resistance coefficient and also to determine the optimum flow resistance with five different flow rate, Q. Laboratory study with two type of vegetation which are Cow Grass and Pearl Grass were implementing to the bed of a flume. The roughness coefficient, n value is determine using Manning’s equation while Soil Conservation Services (SCS) method was used to determine the surface resistance. From the experiment, the flow resistance coefficient for Cow Grass in range 0.0008 - 0.0039 while Pearl Grass value for the flow resistance coefficient are in between 0.0013 - 0.0054. As a conclusion the vegetation roughness value in open channel are depends on density, distribution type of vegetation used and physical characteristic of the vegetation itself

  13. View of Flume Bridge #5 from FS 502 looking downstream ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Flume Bridge #5 from FS 502 looking downstream (south). Bridge is on the left side of the photograph. This is similar to other flume bridges in the system and is the only photograph representing these features. - Childs-Irving Hydroelectric Project, Childs System, Flume Bridge No. 5, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  14. Vertical Flume Testing of WIPP Surrogate Waste Materials

    NASA Astrophysics Data System (ADS)

    Herrick, C. G.; Schuhen, M.; Kicker, D.

    2012-12-01

    The Waste Isolation Pilot Plant (WIPP) is a U.S. Department of Energy geological repository for the permanent disposal of defense-related transuranic (TRU) waste. The waste is emplaced in rooms excavated in the bedded Salado salt formation at a depth of 655 m below ground surface. After emplacement of the waste, the repository will be sealed and decommissioned. The DOE demonstrates compliance with 40 CFR 194 by means of performance assessment (PA) calculations conducted by Sandia National Laboratories. WIPP PA calculations estimate the probability and consequences of radionuclide releases for a 10,000 year regulatory period. Human intrusion scenarios include cases in which a future borehole is drilled through the repository. Drilling mud flowing up the borehole will apply a hydrodynamic shear stress to the borehole wall which could result in erosion of the waste and radionuclides being carried up the borehole. WIPP PA uses the parameter TAUFAIL to represent the shear strength of the degraded waste. The hydrodynamic shear strength can only be measured experimentally by flume testing. Flume testing is typically performed horizontally, mimicking stream or ocean currents. However, in a WIPP intrusion event, the drill bit would penetrate the degraded waste and drilling mud would flow up the borehole in a predominantly vertical direction. In order to simulate this, a flume was designed and built so that the eroding fluid enters an enclosed vertical channel from the bottom and flows up past a specimen of surrogate waste material. The sample is pushed into the current by a piston attached to a step motor. A qualified data acquisition system controls and monitors the fluid's flow rate, temperature, pressure, and conductivity and the step motor's operation. The surrogate materials used correspond to a conservative estimate of degraded TRU waste at the end of the regulatory period. The recipes were previously developed by SNL based on anticipated future states of the waste

  15. Vertical Flume Testing of WIPP Surrogate Waste Materials

    NASA Astrophysics Data System (ADS)

    Herrick, C. G.; Schuhen, M.; Kicker, D.

    2013-12-01

    The Waste Isolation Pilot Plant (WIPP) is a U.S. Department of Energy geological repository for the permanent disposal of defense-related transuranic (TRU) waste. The waste is emplaced in rooms excavated in the bedded Salado salt formation at a depth of 655 m below ground surface. After emplacement of the waste, the repository will be sealed and decommissioned. The DOE demonstrates compliance with 40 CFR 194 by means of performance assessment (PA) calculations conducted by Sandia National Laboratories. WIPP PA calculations estimate the probability and consequences of radionuclide releases for a 10,000 year regulatory period. Human intrusion scenarios include cases in which a future borehole is drilled through the repository. Drilling mud flowing up the borehole will apply a hydrodynamic shear stress to the borehole wall which could result in erosion of the waste and radionuclides being carried up the borehole. WIPP PA uses the parameter TAUFAIL to represent the shear strength of the degraded waste. The hydrodynamic shear strength can only be measured experimentally by flume testing. Flume testing is typically performed horizontally, mimicking stream or ocean currents. However, in a WIPP intrusion event, the drill bit would penetrate the degraded waste and drilling mud would flow up the borehole in a predominantly vertical direction. In order to simulate this, a flume was designed and built so that the eroding fluid enters an enclosed vertical channel from the bottom and flows up past a specimen of surrogate waste material. The sample is pushed into the current by a piston attached to a step motor. A qualified data acquisition system controls and monitors the fluid's flow rate, temperature, pressure, and conductivity and the step motor's operation. The surrogate materials used correspond to a conservative estimate of degraded TRU waste at the end of the regulatory period. The recipes were previously developed by SNL based on anticipated future states of the waste

  16. 8. PECOS RIVER FLUME VIEW OF UNDERSIDE OF SOUTHERNMOST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. PECOS RIVER FLUME - VIEW OF UNDERSIDE OF SOUTHERN-MOST ARCH SHOWING CCC CUTWATER. VIEW TO NORTH - Carlsbad Irrigation District, Pecos River Flume, On Main Canal, .5 mile North of Carlsbad, Carlsbad, Eddy County, NM

  17. Velocity and stage data collected in a laboratory flume for water-surface slope determination using a pipe manometer

    USGS Publications Warehouse

    Lee, Jonathan K.; Visser, H.M.; Jenter, H.L.; Duff, M.P.

    2000-01-01

    U.S. Geological Survey (USGS) hydrologists and ecologist are conducting studies to quantify vegetative flow resistance in order to improve numerical models of surface-water flow in the Florida Everglades. Water-surface slope is perhaps the most difficult of the flow resistance parameters to measure in the Everglades due to the very low gradients of the topography and flow. In an effort to measure these very small slopes, a unique pipe manometer was developed for the local measurement of water-surface slopes on the order of 1 centimeter per kilometer (cm/km). According to theory, a very precise measurement of centerline velocity obtained inside the pipe manometer should serve as a unique proxy for water-surface slope in the direction of the pipe axis. In order to confirm this theoretical relationship and calibrate the pipe manometer, water-surface elevation and pipe centerline velocity data were simultaneously measured in a set of experiments carried out in the tilting flume at the USGS Hydraulic Laboratory Facility at Stennis Space Center, Mississippi. A description of the instrumentation and methods used to evaluate this technique for measuring water-surface slope as well as a summary of the entire data set is presented.

  18. View of Steel Flume Bridge #2 crossing over wash. Looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Steel Flume Bridge #2 crossing over wash. Looking downstream, southwest - Childs-Irving Hydroelectric Project, Childs System, Flume Bridge No. 2, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  19. Closeup view of Flume Bridge #4 showing structural components. Looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Close-up view of Flume Bridge #4 showing structural components. Looking northeast - Childs-Irving Hydroelectric Project, Childs System, Flume Bridge No. 4, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  20. 20. PECOS RIVER FLUME Photographic copy of construction drawing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. PECOS RIVER FLUME - Photographic copy of construction drawing dated February 1905 (from aperture card located at Bureau of Reclamation, Salt Lake City, Utah) EXTENSION OF CONCRETE AQUEDUCT - Carlsbad Irrigation District, Pecos River Flume, On Main Canal, .5 mile North of Carlsbad, Carlsbad, Eddy County, NM

  1. 5. Typical plankcovered flume. View looks west near Luna de ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Typical plank-covered flume. View looks west near Luna de Miel Street. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA

  2. View of Steel Flume Bridge #3 crossing over Sally May ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Steel Flume Bridge #3 crossing over Sally May Wash. Looking northwest - Childs-Irving Hydroelectric Project, Childs System, Flume Bridge No. 3, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  3. View of east entrance to Flume Tunnel #2. In foreground, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of east entrance to Flume Tunnel #2. In foreground, covered decking (covered by debris) protects the flume below it (not visible). The extreme top of the tunnel entrance is visible in the middle of the picture, just beyond the covered decking. This is typical of gravity tunnel entrances and the only photograph representing these features in the system. Looking south - Childs-Irving Hydroelectric Project, Childs System, Flume Tunnel No. 2, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  4. 1. AERIAL VIEW OF BOTH ACTIVE AND INACTIVE FLUMES, TAKEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. AERIAL VIEW OF BOTH ACTIVE AND INACTIVE FLUMES, TAKEN FROM EAST, NOTE STOCK SHELTERS IN BACKGROUND AND HAYSTACKS AND STORAGE IN FOREGROUND - Grant-Kohrs Ranch, Flumes, Highway 10, Deer Lodge, Powell County, MT

  5. 2. Contextual view of flume on hillside, looking east. Trestle ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Contextual view of flume on hillside, looking east. Trestle 6 is visible in the foreground. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA

  6. View of Diversion Dam and Flume Intake of the Childs ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Diversion Dam and Flume Intake of the Childs System at the Irving Powerhouse. Looking northwest - Childs-Irving Hydroelectric Project, Childs System, Flume Intake & Forebay, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  7. 3. VIEW LOOKING NORTH AT CHINA WASH FLUME SHOWING WASH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. VIEW LOOKING NORTH AT CHINA WASH FLUME SHOWING WASH - San Carlos Irrigation Project, China Wash Flume, Main (Florence-Case Grande) Canal at Station 137+00, T4S, R10E, S14, Coolidge, Pinal County, AZ

  8. 41. VIEW FROM END OF FLUME, LOOKING WEST, SHOWING OVERFLOW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. VIEW FROM END OF FLUME, LOOKING WEST, SHOWING OVERFLOW CHUTE ON RIGHT (PARALLEL TO FLUME), RESERVOIR EMBANKMENT IN BACKGROUND, AND HOOKS ON END OF RAILING FOR SPILLBOARDS - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  9. 2. VIEW LOOKING NORTHWEST AT CHINA WASH FLUME ON MAIN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW LOOKING NORTHWEST AT CHINA WASH FLUME ON MAIN CANAL - San Carlos Irrigation Project, China Wash Flume, Main (Florence-Case Grande) Canal at Station 137+00, T4S, R10E, S14, Coolidge, Pinal County, AZ

  10. 1. VIEW LOOKING WEST AT CHINA WASH FLUME ON MAIN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW LOOKING WEST AT CHINA WASH FLUME ON MAIN CANAL. - San Carlos Irrigation Project, China Wash Flume, Main (Florence-Case Grande) Canal at Station 137+00, T4S, R10E, S14, Coolidge, Pinal County, AZ

  11. 17. VIEW OF SETTLING BASIN, SHOWING FLUME TRACK SPUR CROSSING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. VIEW OF SETTLING BASIN, SHOWING FLUME TRACK SPUR CROSSING OVER SETTLING BASIN, SPARE BENT MATERIAL IN RIGHT-HAND FOREGROUND, BYPASS FLUME, AND SHACK #6 IN BACKGROUND, LOOKING NORTHWEST - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  12. 9. HIGH LENNON FLUME, SANTA ANA NO 3, EXHIBIT L, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. HIGH LENNON FLUME, SANTA ANA NO 3, EXHIBIT L, JAN. 25, 1956. SCE drawing no. 541723 (sheet 3; for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, Warm Springs Canyon-SAR-3 Flumes, Redlands, San Bernardino County, CA

  13. 24. Lake Hodges Flume conduit enlargement. April 1930. Courtesy of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Lake Hodges Flume conduit enlargement. April 1930. Courtesy of the Mandeville Department of Special Collections, Central Library, University of California, San Diego. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA

  14. 22. Concrete trestle on Lake Hodges Flume, 1919. Courtesy of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. Concrete trestle on Lake Hodges Flume, 1919. Courtesy of the Mandeville Department of Special Collections, Central Library, University of California, San Diego. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA

  15. 11. INTAKE FLUME AND TUNNEL SECTIONS, SANTA ANA NO. 3, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. INTAKE FLUME AND TUNNEL SECTIONS, SANTA ANA NO. 3, EXHIBIT L, JAN. 25, 1956. SCE drawing no. 541728 (sheet 1; for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, Warm Springs Canyon-SAR-3 Flumes, Redlands, San Bernardino County, CA

  16. 10. TYPICAL DETAILS OF LENNON FLUME, SANTA ANA NO. 3, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. TYPICAL DETAILS OF LENNON FLUME, SANTA ANA NO. 3, EXHIBIT L, JAN. 25, 1956. SCE drawing no. 541722 (sheet 4; for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, Warm Springs Canyon-SAR-3 Flumes, Redlands, San Bernardino County, CA

  17. The influence of fish feed pellets on the stability of seabed sediment: A laboratory flume investigation

    NASA Astrophysics Data System (ADS)

    Neumeier, Urs; Friend, Patrick L.; Gangelhof, Uffe; Lunding, Jens; Lundkvist, Morten; Bergamasco, Alessandro; Amos, Carl L.; Flindt, Mogens

    2007-11-01

    Superfluous fish food settling below fish farms can have a negative impact on the seabed. To aid in the assessment of this impact a series of flume experiments, designed to mimic seabed conditions below a fish farm, was conducted with the aim of examining the effects of fish pellets on the stability of fine sediments. Artificial beds, with varying quantities of fish pellets incorporated both within the sediment matrix and lying on the sediment surface, were allowed to consolidate for different periods of time ranging from 1 to 10 days, and then subjected to erosion experiments. In flume experiments containing fish pellets, a bacterial biofilm developed at the sediment-water interface after a few days. In the control experiments (no fish pellets), a diatom biofilm caused extensive stabilisation of the surface sediment. The erosion experiments showed that the addition of fish pellets reduced the surface erosion threshold by more than 50%. The stability decrease was more pronounced in the experiments with greater amounts of pellets. Evidence of drag reduction due to high suspended sediment concentration was also observed. This phenomenon is discussed and a correction formula is proposed for the effective shear stress experienced by the bed.

  18. 21. Newly completed Lake Hodges Dam and Flume, 1919. Courtesy ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. Newly completed Lake Hodges Dam and Flume, 1919. Courtesy of the Mandeville Department of Special Collection, Central Library, University of California, San Diego. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA

  19. 1. OVERVIEW OF FIFTH FLUME ABOVE SAR1 FOREBAY, SHOWING OLD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. OVERVIEW OF FIFTH FLUME ABOVE SAR-1 FOREBAY, SHOWING OLD AND NEWER CEMENT FOOTINGS. VIEW TO NORTHEAST. - Santa Ana River Hydroelectric System, Flumes & Tunnels below Sandbox, Redlands, San Bernardino County, CA

  20. 10. DETAILS OF STEEL FLUME, TYPICAL BENTS AND TRUSSES. EXHIBIT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. DETAILS OF STEEL FLUME, TYPICAL BENTS AND TRUSSES. EXHIBIT L, SANTA ANA RIVER NO. 1 PROJECT, APR. 30, 1945. SCE drawing no. 523196 (sheet no. 6; for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, Flumes & Tunnels below Sandbox, Redlands, San Bernardino County, CA

  1. 9. DETAILS OF STEEL FLUME, TYPICAL CURVES AND TRANSITIONS. EXHIBIT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. DETAILS OF STEEL FLUME, TYPICAL CURVES AND TRANSITIONS. EXHIBIT L, SANTA ANA RIVER NO. 1 PROJECT, APR. 30, 1945. SCE drawing no. 523195 (sheet no. 5; for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, Flumes & Tunnels below Sandbox, Redlands, San Bernardino County, CA

  2. 2. OVERVIEW OF MAINTENANCE ROAD AND FOURTH FLUME ABOVE SAR1 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. OVERVIEW OF MAINTENANCE ROAD AND FOURTH FLUME ABOVE SAR-1 FOREBAY, HIGH ABOVE SANTA ANA RIVER BED, LOOKING SOUTHWEST. - Santa Ana River Hydroelectric System, Flumes & Tunnels below Sandbox, Redlands, San Bernardino County, CA

  3. Biomass and vegetative characteristics of sawgrass grown in a tilting flume as part of a study of vegetative resistance to flow

    USGS Publications Warehouse

    Rybicki, N.B.; Reel, J.T.; Ruhl, H.; Gammon, P.T.; Carter, Virginia; Lee, J.K.

    1999-01-01

    The U.S. Geological Survey is studying vegetative resistance to flow in the south Florida Everglades as part of a multidisciplinary effort to restore the South Florida Ecosystem. In order to test the flow resistance of sawgrass, one of the dominant species in the Everglades, uniform, dense stands of sawgrass were grown in a tilting flume at Stennis Space Center, Mississippi. Depth of water in the flume was controlled by adding or removing metal plates at the downstream end of the flume. A series of experiments were conducted at various flow depths, and the velocity, flow depth, and water-surface slope were measured. During each set of experiments, the sawgrass was sampled in layers from the sediment water interface for vegetative characteristics, biomass, and leaf area index. The results of the vegetation sampling are summarized in a series of tables.

  4. Deposition of Suspended Clay to Open and Sand-Filled Framework Gravel Beds in a Laboratory Flume

    NASA Astrophysics Data System (ADS)

    Mooneyham, Christian; Strom, Kyle

    2018-01-01

    Pulses of fine sediment composed of sand, silt, and clay can be introduced to gravel bed rivers through runoff from burn-impacted hillslopes, landslides, bank failure, or the introduction of reservoir sediment as a result of sluicing or dam decommissioning. Here we present a study aimed at quantifying exchange between suspensions of clay and gravel beds. The questions that motivate the work are: how do bed roughness and pore space characteristics, shear velocity (u∗), and initial concentration (C0) affect clay deposition on or within gravel beds? Where does deposition within these beds occur, and can deposited clay be resuspended while the gravel is immobile? We examine these questions in a laboratory flume using acrylic, open-framework gravel, and armored sand-gravel beds under conditions of varying u∗ and C0. Deposition of clay occurred to all beds (even with Rouse numbers ˜ 0.01). We attribute deposition under full suspension conditions to be an outcome of localized protected zones where clay can settle and available pore space in the bed. For smooth wall cases, protection came from the viscous wall region and the development of bed forms; for the rough beds, protection came from separation zones and low-velocity pore spaces. Bed porosity was the strongest influencer of nondimensional deposition rate; deposition increased with porosity. Deposition was inversely related to u∗ for the acrylic bed runs; no influence of u∗ was found for the porous bed runs. Increases in discharge resulted in resuspension of clay from acrylic beds; no resuspension was observed in the porous bed runs.

  5. 12. TYPICAL CONCRETELINED CANAL/FLUME TRANSITION (LOCATED JUST WEST OF HIGHWAY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. TYPICAL CONCRETE-LINED CANAL/FLUME TRANSITION (LOCATED JUST WEST OF HIGHWAY 190 CROSSOVER). WATER CONVEYANCE SYSTEM IS COMPRISED OF MULTIPLE INTERSET CONCRETE-LINED CANAL AND FLUME SECTIONS. VIEW TO WEST. - Tule River Hydroelectric Project, Water Conveyance System, Middle Fork Tule River, Springville, Tulare County, CA

  6. View of steel flume (Irving intake system) that is covered ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of steel flume (Irving intake system) that is covered with old flume stock, flattened to protect from debris, animals and daylight, and is supported by wood trestles, as it continues downhill toward the Irving Powerhouse. Truck in photo provides scale. Looking north - Childs-Irving Hydroelectric Project, Irving System, Intake System, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  7. Sensing fluid pressure during plucking events in a natural bedrock channel and experimental flume

    NASA Astrophysics Data System (ADS)

    Wilkinson, C.; Harbor, D. J.; Keel, D.; Levy, S.; Kuehner, J. P.

    2016-12-01

    River channel erosion by plucking is believed to be the dominant erosional process in channels with fractured or jointed bedrock. However, despite its significance as an erosional mechanism, plucking is poorly studied in both laboratory and natural channels. In previous flume studies, model bedrock was plucked by fluid forces alone in nonuniform flow near jumps and waves even where blocks do not protrude into the flow. Here we develop sensor systems to test the hypothesis that bed fluid pressure gradients lift "pluckable" bedrock blocks in a natural field setting and a hydraulic flume. The field setting closely mimics the previous flume setup; the instrumented block is downstream of a roughly 1m step and exhibits no protrusion into the flow. The presence of the step promotes nonuniform flow which changes pressure in the bedrock crack network; slabs of bedrock that have slid downstream and sediment that has been pushed upstream 3-4 m under the bed and in the cracks suggest the influence of pressure differences throughout the crack network and below the bed. In this initial deployment, we evaluate a sensor that monitors movement and simultaneous pressure above and below the block. Sensors are emplaced in a 26kg, 45-cm-long, 20-cm-wide block broken from a 4.5-m-long, 11-cm-thick sandstone bed with a dense network of cracks nearly parallel to flow direction and include a tri-axial accelerometer/gyroscope and two fluid pressure sensors. The electronics are housed in a custom-designed 3D-printed ABS waterproof capsule that is mounted in a vertical hole through the rock. A concurrent flume study develops the sensors necessary to investigate the longitudinal pressure difference below a step using multiple analog sensors (0-1 psi gauge pressure) mounted flush to a false floor under the center of a 30x14-cm test zone. The 15-mm-wide sensors are aligned along the flow centerline and are placed under 25 1-cm-thick "pluckable" bedrock blocks constructed with a proprietary

  8. Experimental studies of deposition at a debris-flow flume

    USGS Publications Warehouse

    Major, Jon J.

    1995-01-01

    Geologists commonly infer the flow conditions and the physical properties of debris flows from the sedimentologic, stratigraphic, and morphologic characteristics of their deposits. However, such inferences commonly lack corroboration by direct observation because the capricious nature of debris flows makes systematic observation and measurement of natural events both difficult and dangerous. Furthermore, in contrast to the numerous experimental studies of water flow and related fluvial deposition, few real-time observations and measurements of sediment deposition by large-scale mass flow of debris under controlled conditions have been made. Recent experiments at the U.S. Geological Survey debris-flow flume in the H. J. Andrews Experimental Forest, Oregon (Iverson and others, 1992) are shedding new insight on sediment deposition by debris flows and on the veracity of methods commonly used to reconstruct flow character from deposit characteristics.

  9. Hydrologic Triggering of Shallow Landslides in a Field-scale Flume

    NASA Astrophysics Data System (ADS)

    Reid, M. E.; Iverson, R. M.; Iverson, N. R.; Brien, D. L.; Lahusen, R. G.; Logan, M.

    2006-12-01

    Hydrologic Triggering of Shallow Landslides in a Field-scale Flume Mark E. Reid, Richard M. Iverson, Neal R. Iverson, Dianne L. Brien, Richard G. LaHusen, and Mathew Logan Shallow landslides are often triggered by pore-water pressure increases driven by 1) groundwater inflow from underlying bedrock or soil, 2) prolonged moderate-intensity rainfall or snowmelt, or 3) bursts of high-intensity rainfall. These shallow failures are difficult to capture in the field, limiting our understanding of how different water pathways control failure style or timing. We used the field-scale, USGS debris-flow flume for 7 controlled landslide initiation experiments designed to examine the influence of different hydrologic triggers and the role of soil density, relative to critical state, on failure style and timing. Using sprinklers and/or groundwater injectors, we induced failure in a 0.65m thick, 2m wide, 6m3 prism of loamy sand on a 31° slope, placed behind a retaining wall. We monitored ~50 sensors to measure soil deformation (tiltmeters & extensometers), pore pressure (tensiometers and transducers), and soil moisture (TDR probes). We also extracted soil samples for laboratory estimates of porosity, shear strength, saturated hydraulic conductivity at differing porosities, unsaturated moisture retention characteristics, and compressibility. Experiments with loose soil all resulted in abrupt failure along the concrete flume bed with rapid mobilization into a debris flow. Each of the 3 water pathways, however, resulted in slightly different pore-pressure fields at failure and different times to failure. For example, groundwater injection at the flume bed led to a saturated zone that advanced upward, wetting over half the soil prism before pressures at the bed were sufficient to provoke collapse. With moderate-intensity surface sprinkling, an unsaturated wetting front propagated downward until reaching the bed, then a saturated zone built upward, with the highest pressures at the

  10. Critical shear stress measurement of cohesive soils in streams: identifying device-dependent variability using an in-situ jet test device and conduit flume

    NASA Astrophysics Data System (ADS)

    Mahalder, B.; Schwartz, J. S.; Palomino, A.; Papanicolaou, T.

    2016-12-01

    Cohesive soil erodibility and threshold shear stress for stream bed and bank are dependent on both soil physical and geochemical properties in association with the channel vegetative conditions. These properties can be spatially variable therefore making critical shear stress measurement in cohesive soil challenging and leads to a need for a more comprehensive understanding of the erosional processes in streams. Several in-situ and flume-type test devices for estimating critical shear stress have been introduced by different researchers; however reported shear stress estimates per device vary widely in orders of magnitude. Advantages and disadvantages exist between these devices. Development of in-situ test devices leave the bed and/or bank material relatively undisturbed and can capture the variable nature of field soil conditions. However, laboratory flumes provide a means to control environmental conditions that can be quantify and tested. This study was conducted to observe differences in critical shear stress using jet tester and a well-controlled conduit flume. Soil samples were collected from the jet test locations and tested in a pressurized flume following standard operational procedure to calculate the critical shear stress. The results were compared using statistical data analysis (mean-separation ANOVA procedure) to identify possible differences. In addition to the device comparison, the mini jet device was used to measure critical shear stress across geologically diverse regions of Tennessee, USA. Statistical correlation between critical shear stress and the soil physical, and geochemical properties were completed identifying that geological origin plays a significant role in critical shear stress prediction for cohesive soils. Finally, the critical shear stress prediction equations using the jet test data were examined with possible suggestions to modify based on the flume test results.

  11. Channel responses to varying sediment input: A flume experiment modeled after Redwood Creek, California

    USGS Publications Warehouse

    Madej, Mary Ann; Sutherland, D.G.; Lisle, T.E.; Pryor, B.

    2009-01-01

    At the reach scale, a channel adjusts to sediment supply and flow through mutual interactions among channel form, bed particle size, and flow dynamics that govern river bed mobility. Sediment can impair the beneficial uses of a river, but the timescales for studying recovery following high sediment loading in the field setting make flume experiments appealing. We use a flume experiment, coupled with field measurements in a gravel-bed river, to explore sediment transport, storage, and mobility relations under various sediment supply conditions. Our flume experiment modeled adjustments of channel morphology, slope, and armoring in a gravel-bed channel. Under moderate sediment increases, channel bed elevation increased and sediment output increased, but channel planform remained similar to pre-feed conditions. During the following degradational cycle, most of the excess sediment was evacuated from the flume and the bed became armored. Under high sediment feed, channel bed elevation increased, the bed became smoother, mid-channel bars and bedload sheets formed, and water surface slope increased. Concurrently, output increased and became more poorly sorted. During the last degradational cycle, the channel became armored and channel incision ceased before all excess sediment was removed. Selective transport of finer material was evident throughout the aggradational cycles and became more pronounced during degradational cycles as the bed became armored. Our flume results of changes in bed elevation, sediment storage, channel morphology, and bed texture parallel those from field surveys of Redwood Creek, northern California, which has exhibited channel bed degradation for 30??years following a large aggradation event in the 1970s. The flume experiment suggested that channel recovery in terms of reestablishing a specific morphology may not occur, but the channel may return to a state of balancing sediment supply and transport capacity.

  12. Mapping Soil Surface Macropores Using Infrared Thermography: An Exploratory Laboratory Study

    PubMed Central

    de Lima, João L. M. P.; Abrantes, João R. C. B.; Silva, Valdemir P.; de Lima, M. Isabel P.; Montenegro, Abelardo A. A.

    2014-01-01

    Macropores and water flow in soils and substrates are complex and are related to topics like preferential flow, nonequilibrium flow, and dual-continuum. Hence, the quantification of the number of macropores and the determination of their geometry are expected to provide a better understanding on the effects of pores on the soil's physical and hydraulic properties. This exploratory study aimed at evaluating the potential of using infrared thermography for mapping macroporosity at the soil surface and estimating the number and size of such macropores. The presented technique was applied to a small scale study (laboratory soil flume). PMID:25371915

  13. Response of a channel with alternate bars to a decrease in supple of mixed-size bedload: A flume experiment

    Treesearch

    Thomas E. Lisle; Fujiko Iseya; Hiroshi Ikeda

    1993-01-01

    The response of a channel with a topography and modeled bed material size typical of gravel bed rivers to reductions in sediment supply was investigated in a laboratory flume filled and fed with a sand-gravel mixture. After a series of quasi-stationary alternate bars were formed under equilibrium sediment transport, feed rate was reduced in two steps to one third and...

  14. Formation of stationary alternate bars in a steep channel with mixed-size sediment: a flume experiment

    Treesearch

    Thomas E. Lisle; Hiroshi Ikeda; Fujiko Iseya

    1991-01-01

    Abstract - Alternate bars were formed by sediment transport in a flume with Froude-modelled flow and relative roughness characteristic of gravel-boulder channels with steep slopes. The flume (0.3 m wide x 7.5 m long) was filled with a sand-gravel mixture, which was also fed into the top of the flume at a constant rate under constant discharge. Channel slope was set at...

  15. Use of pre-fabricated Parshall flumes to measure streamflow in permafrost-dominated watersheds.

    Treesearch

    Charles W. Slaughter

    1981-01-01

    The occurrence of permafrost in stream valleys of central Alaska causes problems with conventional stream-gauging installations. To minimize both thermal and physical disturbance at measurement sites, pre-fabricated Parshall flumes have been used to monitor streamflow at sites underlain with permafrost in a subarctic research watershed. Flumes ranging in capacity from...

  16. Sawgrass Density, Biomass, and Leaf Area Index: A Flume Study in Support of Research on Wind Sheltering Effects in the Florida Everglades

    USGS Publications Warehouse

    Rybicki, Nancy B.; Reel, Justin T.; Ruhl, Henry A.; Gammon, Patricia T.; Carter, Virginia; Lee, Jonathan K.

    2000-01-01

    The U.S. Geological Survey is studying the wind sheltering effects of vegetation in the Florida Everglades. In order to test both the flow resistance and wind sheltering effects of sawgrass, uniform dense stands of sawgrass were grown in a tilting flume at Stennis Space Center, Mississippi. In June, 1997, one end of the flume was covered with a wind cowling with a removable top, and a series of experiments were conducted between June, 1997 and July, 1998. During each set of experiments, the sawgrass was sampled for vegetative characteristics, biomass, and leaf area index. The results of the analyses of the vegetation samples are summarized in a series of appendixes.

  17. Flumes, historic water yield and climatological data for Tenderfoot Creek Experimental Forest, Montana

    Treesearch

    Phillip E. Farnes; Ward W. McCaughey; Katherine J. Hansen

    1999-01-01

    The objectives of this Research Joint Venture Agreement (RJVA) were to install and calibrate three flumes on Tenderfoot Creek Experimental Forest (TCEF) in central Montana; check calibration of the existing seven flumes on TCEF; estimate the influence of fire on water yields over the 400-year fire history period; and estimate back records of monthly temperature,...

  18. Finite element simulation of cracks formation in parabolic flume above fixed service live

    NASA Astrophysics Data System (ADS)

    Bandurin, M. A.; Volosukhin, V. A.; Mikheev, A. V.; Volosukhin, Y. V.; Bandurina, I. P.

    2018-03-01

    In the article, digital simulation data on influence of defect different characteristics on cracks formation in a parabolic flume are presented. The finite element method is based on general hypotheses of the theory of elasticity. The studies showed that the values of absolute movements satisfy the standards of design. The results of the digital simulation of stresses and strains for cracks formation in concrete parabolic flumes after long-term service above the fixed service life are described. Stressed and strained state of reinforced concrete bearing elements under different load combinations is considered. Intensive threshold of danger to form longitudinal cracks in reinforced concrete elements is determined.

  19. Calibrating a numerical model's morphology using high-resolution spatial and temporal datasets from multithread channel flume experiments.

    NASA Astrophysics Data System (ADS)

    Javernick, L.; Bertoldi, W.; Redolfi, M.

    2017-12-01

    Accessing or acquiring high quality, low-cost topographic data has never been easier due to recent developments of the photogrammetric techniques of Structure-from-Motion (SfM). Researchers can acquire the necessary SfM imagery with various platforms, with the ability to capture millimetre resolution and accuracy, or large-scale areas with the help of unmanned platforms. Such datasets in combination with numerical modelling have opened up new opportunities to study river environments physical and ecological relationships. While numerical models overall predictive accuracy is most influenced by topography, proper model calibration requires hydraulic data and morphological data; however, rich hydraulic and morphological datasets remain scarce. This lack in field and laboratory data has limited model advancement through the inability to properly calibrate, assess sensitivity, and validate the models performance. However, new time-lapse imagery techniques have shown success in identifying instantaneous sediment transport in flume experiments and their ability to improve hydraulic model calibration. With new capabilities to capture high resolution spatial and temporal datasets of flume experiments, there is a need to further assess model performance. To address this demand, this research used braided river flume experiments and captured time-lapse observed sediment transport and repeat SfM elevation surveys to provide unprecedented spatial and temporal datasets. Through newly created metrics that quantified observed and modeled activation, deactivation, and bank erosion rates, the numerical model Delft3d was calibrated. This increased temporal data of both high-resolution time series and long-term temporal coverage provided significantly improved calibration routines that refined calibration parameterization. Model results show that there is a trade-off between achieving quantitative statistical and qualitative morphological representations. Specifically, statistical

  20. GATE AND VACUUM FLUSHING OF SEWER SEDIMENT: LABORATORY TESTING

    EPA Science Inventory

    The objective of this study was to test the performance of a traditional gate-flushing device and a newly-designed vacuum-flushing device in removing sediment from combined sewers and CSO storage tanks. A laboratory hydraulic flume was used to simulate a reach of sewer or storag...

  1. Soil erosion transport through multiple rainfall events in the presence of stone cover: Laboratory flume experiments and analysis with the Hairsine-Rose model

    NASA Astrophysics Data System (ADS)

    Jomaa, S.; Barry, D. A.; Brovelli, A.; Heng, B. P.; Sander, G. C.; Parlange, J.

    2011-12-01

    Soil erosion is a major environmental problem that can lead to loss of fertility and degradation of agricultural fields. In order to develop efficient strategies to mitigate the impact of precipitation and reduce the erosion rate, a process-based understanding of the mechanisms that govern sediment transport and delivery is necessary. Soil state and physical properties prior to a precipitation event can affect significantly the erosion rate. Among the most important soil variables are moisture content, compaction and infiltration capacity. Additionally, the presence of stones on the topsoil surface retards the overland flow discharge, reduces runoff generation as well as the sediment delivery and prevents the development of a surface seal, which in turn maintains the infiltration rate. The aim of this study was to examine in detail the effect of surface stones, soil compaction and sealing for a sequence of rainfall events on soil erosion. Experiments were conducted using the EPFL erosion flume, which was divided into two identical flumes (one with stone and one without). The experiment involved four rainfall events with the precipitation rates: 28, 74, 74 and 28 mm h-1. After each 2-h event, the soil was allowed to air dry for 22 h. The total sediment concentration, the concentration of seven sediment size classes and the flow discharge were measured during each event at the outlet of each flume. Experimental results were analyzed using the Hairsine and Rose (H-R) soil erosion model. Results showed that (i) within each precipitation event, the proportion of each size class for the bare/stone-covered flume pairs at steady state were similar, whereas the initial response differed significantly; (ii) in all cases the effluent was enriched in finer particles relative to the original soil; and (iii) the effluent sediment composition was different from that of the original soil, and there was no clear trend towards the parent soil sediment size composition with time. The

  2. Mechanisms linking sediment supply and bar morphology: Results from a straight flume with alternate bars

    NASA Astrophysics Data System (ADS)

    Braudrick, C. A.; Minear, J. T.; Dietrich, W. E.; Dehart, M.; Sklar, L. S.

    2008-12-01

    One of the largest uncertainties in routing sediment through drainage networks is predicting the degree to which changes in sediment supply are mitigated by changes in sediment storage in bars. We hypothesize that changes in topographic steering link sediment supply and bar morphology. This hypothesis posits that increased sediment supply would enhance topographic steering over the bar, causing the bar to advance laterally into the pool. Contrarily, decreased supply would diminish topographic steering, causing bars to shrink laterally and pools to expand. We examined this hypothesis in a 28-m long, 0.86-m wide flume with a constant discharge of 5.4 l/s and sand with a median grain size of 0.8 mm. The conditions were sufficient to support alternate bars downstream of the upper 8-10 m, and the flume was run for approximately 65 hours at a constant discharge and sediment feed. The equilibrium slope was 0.0033. Once the channel reached equilibrium, the sediment feed was turned off while the discharge was held constant. During the first 25 hours after the feed was stopped, the sediment transport rate at the downstream end of the flume increased from 9.8 to 10.5 kg/hr as sediment was provided by incision at the upstream end of the flume. Because the bed was the only sediment source, sediment supply increased with distance down the flume. Once the feed was shut off, bar response differed between the upstream and downstream portions of the flume. Bars at the downstream end of the flume, where sediment supply increased relative to equilibrium conditions, swelled into the pool. These changes in bar morphology were accompanied by a decrease in surface grain size. Further upstream, where sediment supply was lower, the bars shrunk. These results suggest that there may be a linkage between topographic steering, bar morphology, and sediment supply, but further numerical tests and experimental manipulations are necessary to verify this linkage and to account for the effect of the

  3. 1. BLACK RIVER CANAL PARSHALL FLUME AT UPPER END ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. BLACK RIVER CANAL - PARSHALL FLUME AT UPPER END OF SUPPLY (USED BY STATE ENGINEER). VIEW TO NORTHEAST - Carlsbad Irrigation District, Black River Canal, 15 miles Southeast of Carlsbad near Malaga, Carlsbad, Eddy County, NM

  4. Comparison of flume and towing methods for verifying the calibration of a suspended-sediment sampler

    USGS Publications Warehouse

    Beverage, J.P.; Futrell, J.C.

    1986-01-01

    Suspended-sediment samplers must sample isokinetically (at stream velocity) in order to collect representative water samples of rivers. Each sampler solo by the Federal Interagency Sedimentation Project or by the U.S. Geological Survey Hydrologic Instrumentation Facility has been adjusted to sample isokinetically and tested in a flume to verify the calibration. The test program for a modified U.S. P-61 sampler provided an opportunity to compare flume and towing tank tests. Although the two tests yielded statistically distinct results, the difference between them was quite small. The conclusion is that verifying the calibration of any suspended-sediment sampler by either the flume or towing method should give acceptable results.

  5. 14. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM TOWARD SETTLING BASIN, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM TOWARD SETTLING BASIN, SHOWING RIGHT FORK TO BYPASS, LEFT FORK TO BASIN - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  6. 81. VIEW OF CONNECTION BETWEEN INTAKE AND FLUME, SHOWING UNCOMPLETED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    81. VIEW OF CONNECTION BETWEEN INTAKE AND FLUME, SHOWING UNCOMPLETED RADIAL GATE IN PLACE, Print No. 240, April 1904 - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  7. 65. VIEW LOOKING UPSTREAM FROM FLUME SUBSTRUCTURE, SHOWING COLUMBIA IMPROVEMENT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    65. VIEW LOOKING UPSTREAM FROM FLUME SUBSTRUCTURE, SHOWING COLUMBIA IMPROVEMENT COMPANY'S NEISSON CREEK SAWMILL. Print No. 177, November 1903 - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  8. View of Irving Intake System showing shed and steel flume. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Irving Intake System showing shed and steel flume. Looking west-northwest - Childs-Irving Hydroelectric Project, Irving System, Intake System, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  9. Laboratory and field investigations of wave attenuation by live marsh vegetation

    USDA-ARS?s Scientific Manuscript database

    Wave attenuation by live marsh vegetation was investigated experimentally in this study. Laboratory experiments were conducted in a 20.6 m long, 0.69 m wide and 1.22 m deep wave flume under regular and random waves. The vegetation species used are Spartina alterniflora and Juncus roemerianus, which ...

  10. Video documentation of experiments at the USGS debris-flow flume 1992–2017

    USGS Publications Warehouse

    Logan, Matthew; Iverson, Richard M.

    2007-11-23

    This set of videos presents about 18 hours of footage documenting the 163 experiments conducted at the USGS debris-flow flume from 1992 to 2017. Owing to improvements in video technology over the years, the quality of footage from recent experiments generally exceeds that from earlier experiments.Use the list below to access the individual videos, which are mostly grouped by date and subject matter. When a video is selected from the list, multiple video sequences are generally shown in succession, beginning with a far-field overview and proceeding to close-up views and post-experiment documentation.Interpretations and data from experiments at the USGS debris-flow flume are not provided here but can be found in published reports, many of which are available online at: https://profile.usgs.gov/riverson/A brief introduction to the flume facility is also available online in USGS Open-File Report 92–483 [http://pubs.er.usgs.gov/usgspubs/ofr/ofr92483].

  11. Flume and field-based calibration of surrogate sensors for monitoring bedload transport

    NASA Astrophysics Data System (ADS)

    Mao, L.; Carrillo, R.; Escauriaza, C.; Iroume, A.

    2016-01-01

    Bedload transport assessment is important for geomorphological, engineering, and ecological studies of gravel-bed rivers. Bedload can be monitored at experimental stations that require expensive maintenance or by using portable traps, which allows measuring instantaneous transport rates but at a single point and at high costs and operational risks. The need for continuously measuring bedload intensity and dynamics has therefore increased the use and enhancement of surrogate methods. This paper reports on a set of flume experiments in which a Japanese acoustic pipe and an impact plate have been tested using four well-sorted and three poorly sorted sediment mixtures. Additional data were collected in a glacierized high-gradient Andean stream (Estero Morales) using a portable Bunte-type bedload sampler. Results show that the data provided by the acoustic pipe (which is amplified on 6 channels having different gains) can be calibrated for the grain size and for the intensity of transported sediments coarser than 9 mm (R2 = 0.93 and 0.88, respectively). Even if the flume-based calibration is very robust, upscaling the calibration to field applications is more challenging, and the bedload intensity could be predicted better than the grain size of transported sediments (R2 = 0.61 and 0.43, respectively). The inexpensive impact plate equipped with accelerometer could be calibrated for bedload intensity quite well in the flume but only poorly in the field (R2 = 0.16) and could not provide information on the size of transported sediments.

  12. 70. VIEW OF PARTIALLY COMPLETED FLUME BELOW THE AUTOMATIC SPILL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    70. VIEW OF PARTIALLY COMPLETED FLUME BELOW THE AUTOMATIC SPILL AT THE RESERVOIR, SHOWING MOUNT RAINIER IN THE DISTANCE, Print No. 192, December 1903 - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  13. 46. VIEW, LOOKING WEST FROM DETERIORATED END OF FLUME AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. VIEW, LOOKING WEST FROM DETERIORATED END OF FLUME AT RESERVOIR'S EAST EDGE, SHOWING DREDGE IN LEFT BACKGROUND, SIDE VIEW OF FOREBAY SHED ON RIGHT - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  14. 15. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM, LEFT FORK TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM, LEFT FORK TO SETTLING BASIN, SHOWING RIGHT FORK WITH GATE IN PLACE AND A FEW NEEDLES IN PLACE - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  15. Student-Designed Flume Arrives at NWTC | News | NREL

    Science.gov Websites

    opportunity to plan, design, and construct a flume for testing and characterizing hydrokinetic power devices . The project was one of several open to CSM students as part of the Capstone Design@Mines program transported to the National Wind Technology Center (NWTC) on Dec. 7. "The design and construction of the

  16. 78. VIEW OF UNCOMPLETED RESERVOIR, SHOWING FOREBAY AND FLUME; ALSO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    78. VIEW OF UNCOMPLETED RESERVOIR, SHOWING FOREBAY AND FLUME; ALSO SHOWING POOL ARRANGEMENT FOR TEMPORARILY UTILIZING WATER WITHOUT FILLING THE RESERVOIR, Print No. 232, April 1904 - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  17. 1. VIEW OF POWER PLANT LOOKING SOUTHEAST. SEVEN TURBINE FLUMES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW OF POWER PLANT LOOKING SOUTHEAST. SEVEN TURBINE FLUMES VISIBLE IN FRONT OF BUILDING. - Potomac Power Plant, On West Virginia Shore of Potomac River, about 1 mile upriver from confluence with Shenandoah River, Harpers Ferry, Jefferson County, WV

  18. Bead Roller, at right, used for preparing flume sheeting (still ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Bead Roller, at right, used for preparing flume sheeting (still in use, 2004); on left is a pipe cutter. Facing southeast - Childs-Irving Hydroelectric Project, Childs System, Childs Powerhouse, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  19. 9. Upstream view showing diversion flume at lower left and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Upstream view showing diversion flume at lower left and mixing plant at left center. Photographer unknown, June 9, 1924. Source: Salt River Project. - Mormon Flat Dam, On Salt River, Eastern Maricopa County, east of Phoenix, Phoenix, Maricopa County, AZ

  20. Laboratory evaluation of an OTT acoustic digital current meter and a SonTek Laboratory acoustic Doppler velocimeter

    USGS Publications Warehouse

    Vermeyen, T.B.; Oberg, Kevin A.; Jackson, Patrick Ryan

    2009-01-01

    Recently, an acoustic current meter known as the OTT * acoustic digital current meter (ADC) was introduced as an alternative instrument for stream gaging measurements. The Bureau of Reclamation and the U.S. Geological Survey collaborated on a side- by-side evaluation of the ADC and a SonTek/YSI acoustic Doppler velocimeter (ADV). Measurements were carried out in a laboratory flume to evaluate the performance characteristics of the ADC under a range of flow and boundary conditions. The flume contained a physical model of a mountain river with a diversion dam and variety of bed materials ranging from smooth mortar to a cobble bed. The instruments were installed on a trolley system that allowed them to be easily moved within the flume while maintaining a consistent probe orientation. More than 50 comparison measurements were made in an effort to verify the manufacturer’s performance specifications and to evaluate potential boundary disturbance for near-bed and vertical boundary measurements. Data and results from this evaluation are presented and discussed. 

  1. 69. VIEW OF FOREBAY AND RESERVOIR, SHOWING FLUME ENTRANCE TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    69. VIEW OF FOREBAY AND RESERVOIR, SHOWING FLUME ENTRANCE TO RESERVOIR ON THE RIGHT OF FOREBAY IN THE BACKGROUND (SHOWN BY THE WHITE X ON THE PHOTOGRAPHS), Print No. 191, December 1903 - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  2. 40. VIEW, LOOKING WEST, OF TOP OF FLUME NEAR FOREBAY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. VIEW, LOOKING WEST, OF TOP OF FLUME NEAR FOREBAY, SHOWING LUMBER SHED, TWO TRACKS, CRANEWAY SHED IN BACKGROUND, RESERVOIR TO LEFT, RIGHT TO YARDS AND FACILITIES, AND OVERFLOW SPILLWAY ON LOWER RIGHT - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  3. Evaluation of swimming performance for fish passage of longnose dace Rhinichthys cataractae using an experimental flume.

    PubMed

    Dockery, D R; McMahon, T E; Kappenman, K M; Blank, M

    2017-03-01

    The swimming performance of longnose dace Rhinichthys cataractae, the most widely distributed minnow (Cyprinidae) in North America, was assessed in relation to potential passage barriers. The study estimated passage success, maximum ascent distances and maximum sprint speed in an open-channel flume over a range of water velocities and temperatures (10·7, 15·3 and 19·3° C). Rhinichthys cataractae had high passage success (95%) in a 9·2 m flume section at mean test velocities of 39 and 64 cm s -1 , but success rate dropped to 66% at 78 cm s -1 . Only 20% of fish were able to ascend a 2·7 m section with a mean velocity of 122 cm s -1 . Rhinichthys cataractae actively selected low-velocity pathways located along the bottom and corners of the flume at all test velocities and adopted position-holding behaviour at higher water velocities. Mean volitional sprint speed was 174 cm s -1 when fish volitionally sprinted in areas of high water velocities. Swimming performance generally increased with water temperature and fish length. Based on these results, fishways with mean velocities <64 cm s -1 should allow passage of most R. cataractae. Water velocities >100 cm s -1 within structures should be limited to short distance (<1 m) and structures with velocities ≥158 cm s -1 would probably represent movement barriers. Study results highlighted the advantages of evaluating a multitude of swimming performance metrics in an open-channel flume, which can simulate the hydraulic features of fishways and allow for behavioural observations that can facilitate the design of effective passage structures. © 2016 The Fisheries Society of the British Isles.

  4. Evaluation of current operating standards for chlorine dioxide in disinfection of dump tank and flume for fresh tomatoes.

    PubMed

    Tomás-Callejas, Alejandro; López-Velasco, Gabriela; Valadez, Angela M; Sbodio, Adrian; Artés-Hernández, Francisco; Danyluk, Michelle D; Suslow, Trevor V

    2012-02-01

    Standard postharvest unit operations that rely on copious water contact, such as fruit unloading and washing, approach the criteria for a true critical control point in fresh tomato production. Performance data for approved sanitizers that reflect commercial systems are needed to set standards for audit compliance. This study was conducted to evaluate the efficacy of chlorine dioxide (ClO(2)) for water disinfection as an objective assessment of recent industry-adopted standards for dump tank and flume management in fresh tomato packing operations. On-site assessments were conducted during eight temporally distinct shifts in two Florida packinghouses and one California packinghouse. Microbiological analyses of incoming and washed fruit and dump and flume system water were evaluated. Water temperature, pH, turbidity, conductivity, and oxidation-reduction potential (ORP) were monitored. Reduction in populations of mesophilic and coliform bacteria on fruit was not significant, and populations were significantly higher (P < 0.05) after washing. Escherichia coli was near the limit of detection in dump tanks but consistently below the detection limit in flumes. Turbidity and conductivity increased with loads of incoming tomatoes. Water temperature varied during daily operations, but pH and ORP mostly remained constant. The industry standard positive temperature differential of 5.5°C between water and fruit pulp was not maintained in tanks during the full daily operation. ORP values were significantly higher in the flume than in the dump tank. A positive correlation was found between ORP and temperature, and negative correlations were found between ORP and turbidity, total mesophilic bacteria, and coliforms. This study provides in-plant data indicating that ClO(2) can be an effective sanitizer in flume and spray-wash systems, but current operational limitations restrict its performance in dump tanks. Under current conditions, ClO(2) alone is unlikely to allow the fresh

  5. VIEW OF IRVING FLUME FROM FOSSIL SPRINGS (LINE THROUGH CENTER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF IRVING FLUME FROM FOSSIL SPRINGS (LINE THROUGH CENTER OF PHOTO) AND LOCATION OF IRVING POWER PLANT (LEFT CENTER) FROM FOREST SERVICE (FS) ROAD #708 (STRAWBERRY TO IRVING). LOOKING DOWNSTREAM (SOUTH-SOUTHWEST) - Childs-Irving Hydroelectric Project, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

  6. Avulsion research using flume experiments and highly accurate and temporal-rich SfM datasets

    NASA Astrophysics Data System (ADS)

    Javernick, L.; Bertoldi, W.; Vitti, A.

    2017-12-01

    SfM's ability to produce high-quality, large-scale digital elevation models (DEMs) of complicated and rapidly evolving systems has made it a valuable technique for low-budget researchers and practitioners. While SfM has provided valuable datasets that capture single-flood event DEMs, there is an increasing scientific need to capture higher temporal resolution datasets that can quantify the evolutionary processes instead of pre- and post-flood snapshots. However, flood events' dangerous field conditions and image matching challenges (e.g. wind, rain) prevent quality SfM-image acquisition. Conversely, flume experiments offer opportunities to document flood events, but achieving consistent and accurate DEMs to detect subtle changes in dry and inundated areas remains a challenge for SfM (e.g. parabolic error signatures).This research aimed at investigating the impact of naturally occurring and manipulated avulsions on braided river morphology and on the encroachment of floodplain vegetation, using laboratory experiments. This required DEMs with millimeter accuracy and precision and at a temporal resolution to capture the processes. SfM was chosen as it offered the most practical method. Through redundant local network design and a meticulous ground control point (GCP) survey with a Leica Total Station in red laser configuration (reported 2 mm accuracy), the SfM residual errors compared to separate ground truthing data produced mean errors of 1.5 mm (accuracy) and standard deviations of 1.4 mm (precision) without parabolic error signatures. Lighting conditions in the flume were limited to uniform, oblique, and filtered LED strips, which removed glint and thus improved bed elevation mean errors to 4 mm, but errors were further reduced by means of an open source software for refraction correction. The obtained datasets have provided the ability to quantify how small flood events with avulsion can have similar morphologic and vegetation impacts as large flood events

  7. Idealized debris flow in flume with bed driven by a conveyor belt

    USGS Publications Warehouse

    Ling, Chi-Hai; Chen, Cheng-lung

    1989-01-01

    The generalized viscoplastic fluid (GVF) model is used to derive the theoretical expressions of two-dimensional velocities and surface profile for debris flow established in a flume with bed driven by a conveyor belt. The rheological parameters of the GVF model are evaluated through the comparison of theoretical results with measured data. A slip velocity of the established (steady) nonuniform flow on the moving bed (i.e., the conveyor belt) is observed, and a relation between the slip velocity and the velocity gradient at the bed is derived. Two belts, one rough and the other smooth, were tested. The flow profile in the flume is found to be linear and dependent on the roughness of the belt, but not much on its speed.

  8. Analysis of sediment particle velocity in wave motion based on wave flume experiments

    NASA Astrophysics Data System (ADS)

    Krupiński, Adam

    2012-10-01

    The experiment described was one of the elements of research into sediment transport conducted by the Division of Geotechnics of West-Pomeranian University of Technology. The experimental analyses were performed within the framework of the project "Building a knowledge transfer network on the directions and perspectives of developing wave laboratory and in situ research using innovative research equipment" launched by the Institute of Hydroengineering of the Polish Academy of Sciences in Gdańsk. The objective of the experiment was to determine relations between sediment transport and wave motion parameters and then use the obtained results to modify formulas defining sediment transport in rivers, like Ackers-White formula, by introducing basic parameters of wave motion as the force generating bed material transport. The article presents selected results of the experiment concerning sediment velocity field analysis conducted for different parameters of wave motion. The velocity vectors of particles suspended in water were measured with a Particle Image Velocimetry (PIV) apparatus registering suspended particles in a measurement flume by producing a series of laser pulses and analysing their displacement with a high-sensitivity camera connected to a computer. The article presents velocity fields of suspended bed material particles measured in the longitudinal section of the wave flume and their comparison with water velocity profiles calculated for the definite wave parameters. The results presented will be used in further research for relating parameters essential for the description of monochromatic wave motion to basic sediment transport parameters and "transforming" mean velocity and dynamic velocity in steady motion to mean wave front velocity and dynamic velocity in wave motion for a single wave.

  9. Comparisons of Derived Metrics from Computed Tomography (CT) Scanned Images of Fluvial Sediment from Gravel-Bed Flume Experiments

    NASA Astrophysics Data System (ADS)

    Voepel, Hal; Ahmed, Sharif; Hodge, Rebecca; Leyland, Julian; Sear, David

    2016-04-01

    Uncertainty in bedload estimates for gravel bed rivers is largely driven by our inability to characterize arrangement, orientation and resultant forces of fluvial sediment in river beds. Water working of grains leads to structural differences between areas of the bed through particle sorting, packing, imbrication, mortaring and degree of bed armoring. In this study, non-destructive, micro-focus X-ray computed tomography (CT) imaging in 3D is used to visualize, quantify and assess the internal geometry of sections of a flume bed that have been extracted keeping their fabric intact. Flume experiments were conducted at 1:1 scaling of our prototype river. From the volume, center of mass, points of contact, and protrusion of individual grains derived from 3D scan data we estimate 3D static force properties at the grain-scale such as pivoting angles, buoyancy and gravity forces, and local grain exposure. Here metrics are derived for images from two flume experiments: one with a bed of coarse grains (>4mm) and the other where sand and clay were incorporated into the coarse flume bed. In addition to deriving force networks, comparison of metrics such as critical shear stress, pivot angles, grain distributions, principle axis orientation, and pore space over depth are made. This is the first time bed stability has been studied in 3D using CT scanned images of sediment from the bed surface to depths well into the subsurface. The derived metrics, inter-granular relationships and characterization of bed structures will lead to improved bedload estimates with reduced uncertainty, as well as improved understanding of relationships between sediment structure, grain size distribution and channel topography.

  10. 85. INCLINED PLANE 7 EAST. FLUME AND STONE POWER HOUSE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    85. INCLINED PLANE 7 EAST. FLUME AND STONE POWER HOUSE ARE ON RIGHT SIDE OF PHOTOGRAPH. NOTE THE CABLE LEAVING THE POWER HOUSE. THIS CABLE IS ATTATCHED TO A DRUM ON THE INSIDE THE POWER HOUSE WHICH IS TURNED BY MEANS OF A WATER POWERED TURBINE. - Morris Canal, Phillipsburg, Warren County, NJ

  11. 26. Photocopy of engineering drawing. PROJECT WS315A: FLUME AND RETENTION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Photocopy of engineering drawing. PROJECT WS-315A: FLUME AND RETENTION PONDS-STRUCTURAL AND MECHANICAL, APRIL 1956. - Cape Canaveral Air Station, Launch Complex 17, Facility 28501, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

  12. Engineering Hyporheic Zones to Attenuate Heavy Metals in Constructed Urban Streams: Performance Data from Constructed Stream Flumes

    NASA Astrophysics Data System (ADS)

    Halpin, B. N.; Portmann, A. C.; Herzog, S.; Higgins, C.; McCray, J. E.

    2017-12-01

    Urban stormwater runoff is a major cause of water quality impairment along ocean shorelines and in rivers, lakes and estuaries across the United States. In addition to pathogens, nutrients, and organic contaminants, a variety of heavy metals are commonly found at elevated concentrations in urban runoff. Although such metals occur in both dissolved and particulate-bound phases, conventional stormwater controls are typically designed to remove suspended solids, while dissolved phase contaminants remain largely untreated. To address this gap in available stormwater controls, a novel technology, termed Biohydrochemical Enhancements for Streamwater Treatment (BEST), has been developed based on inspiration from the natural hyporheic zone (HZ). BEST utilizes a series of alternating streambed permeabilities to drive efficient surface water-HZ exchange. This is combined with reactive and/or sorptive streambed geomedia designed to remove dissolved phase contaminants from constructed urban drainage channels. Previous research at the Colorado School of Mines has shown that a 15-meter flume modified with BEST exhibits greater hyporheic exchange than an all-sand control flume, though both flumes provided greater contaminant attenuation than a selection of actual urban streams. This study again utilized the 15-meter flumes at Colorado School of Mines to evaluate two configurations of BEST for removal of heavy metals commonly found in stormwater runoff, including cadmium, copper, nickel, lead and zinc. In both BEST configurations, the geomedia consisted of a 30/70 (v/v) mix of woodchips and sand, with one configuration using coarse sand (K=0.48 cm/s) and the other using finer sand (K=0.16 cm/s). Both configurations were compared to an all-sand control. To evaluate metals removal, a suite of aqueous metals solution was spiked into each flume, and aqueous concentrations of the five metals of interest were monitored in both the surface and pore water over 24 hours. Differences in

  13. 7. OVERVIEW OF FLUME LINE RUNNING ALONG NORTH SIDE OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. OVERVIEW OF FLUME LINE RUNNING ALONG NORTH SIDE OF TULE RIVER MIDDLE FORK CANYON TOWARD SIPHON CANYON FROM A POINT APPROXIMATELY ONE QUARTER MILE EAST OF FORBAY. EAST END OF DOUBLE-BARREL SIPHON IS VISIBLE IN THE DISTANCE AT PHOTO RIGHT CENTER BELOW CLOUDS. VIEW TO EAST. - Tule River Hydroelectric Project, Water Conveyance System, Middle Fork Tule River, Springville, Tulare County, CA

  14. Cyclic steps due to the surge-type turbidity currents in flume experiments: effect of surge duration on the topography of steps

    NASA Astrophysics Data System (ADS)

    Yokokawa, Miwa; Yamano, Junpei; Miyai, Masatomo; Hughes Clarke, John; Izumi, Norihiro

    2017-04-01

    Field observations of turbidity currents and seabed topography on the Squamish delta in British Columbia, Canada revealed that cyclic steps formed by the surge-type turbidity currents (e.g., Hughes Clarke et al., 2014). The high-density portion of the flow, which affects the sea floor morphology, lasted only 30-60 seconds. We are doing flume experiments aiming to investigate the relationship between the condition of surges and topography of resultant steps. In this presentation, we are going to discuss about the effect of surge duration on the topography of steps. The experiments have been performed at Osaka Institute of Technology. A flume, which is 7.0 m long, 0.3 m deep and 2 cm wide, was suspended in a larger tank, which is 7.6 m long, 1.2 m deep and 0.3 m wide, filled with water. The inner flume tilted at 7 degrees. As a source of turbidity currents, mixture of salt water (1.17 g/cm^3) and plastic particles (1.3 g/cm^3, 0.1-0.18 mm in diameter) was prepared. The concentration of the sediments was 6.1 weight % (5.5 volume %) in the head tank. This mixture of salt water and plastic particles poured into the upstream end of the inner flume from head tank for 3 seconds or 7 seconds. 140 surges were made respectively. Discharge of the currents were fluctuated but range from 306 to 870 mL for 3s-surge, and from 1134 to 2030 mL for 7s-surge. As a result, five or six steps were formed respectively. At the case of 3s-surge, steps located at upstream portion of the flume moved vigorously toward upstream direction, whereas steps at downstream portion of the flume moved toward upstream direction at the case of 7s-surge. The wavelengths and wave heights of the steps by 3s-surge are larger than those of 7s-surge at the upstream portion of the flume, but the size of steps of 3s-surge are smaller than those of 7s-surge at the downstream portion of the flume. In this condition of slope and concentration, the longer surge duration, i.e. larger discharge of the current

  15. 15. OVERVIEW OF TULE RIVER POWERHOUSE FROM FLUME SECTION JUST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. OVERVIEW OF TULE RIVER POWERHOUSE FROM FLUME SECTION JUST SOUTHEAST OF FOREBAY SHOWING BYPASSED SEGMENT OF OLD HIGHWAY 190 IN FRONT OF POWERHOUSE A PHOTO RIGHT CENTER. TAILRACE FROM POWERHOUSE DISCHARGES PROJECT WATER BACK INTO TULE RIVER MIDDLE FORK JUST OUT OF VIEW AT EXTREME LEFT OF PHOTO. VIEW TO SOUTHWEST. - Tule River Hydroelectric Project, Water Conveyance System, Middle Fork Tule River, Springville, Tulare County, CA

  16. 10. WHITNEY'S FLUME AND VIEW OF THE CONFLUENCE OF TONTO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. WHITNEY'S FLUME AND VIEW OF THE CONFLUENCE OF TONTO CREEK AND THE SALT RIVER. AREA SHOWN IS PRESENTLY UNDER WATER. TONTO CREEK FLOWS FROM BACKGROUND CENTER TO LEFT, AND THE SALT RIVER FLOWS FROM RIGHT TO LEFT IN THE PHOTO. DAM IS LOCATED OFF THE PHOTO TO THE LEFT Photographer: Walter J. Lubken, March 3, 1906 - Roosevelt Power Canal & Diversion Dam, Parallels Salt River, Roosevelt, Gila County, AZ

  17. Laboratory Study on the Effect of Tidal Stream Turbines on Hydrodynamics and Sediment Dynamics

    NASA Astrophysics Data System (ADS)

    Amoudry, L.; Ramirez-Mendoza, R.; Peter, T.; McLelland, S.; Simmons, S.; Parsons, D. R.; Vybulkova, L.

    2016-02-01

    Tidal stream turbines (TST) are one potential technology for harnessing tidal energy, and the measurement and characterisation of their wakes is important both for environmental and development reasons. Indeed, wake recovery length is an important parameter for appropriate design of arrays, and wakes may result in altered dynamics both in the water column and at the seabed. We will report on laboratory scale experiments over a mobile sediment bed, which aim to quantify the detailed wake structure and its impact on sediment transport dynamics. A 0.2 m diameter model turbine was installed in a large-scale flume (16 m long, 1.6 m wide, 0.6 m deep) at the University of Hull's Total Environment Simulator and a steady current was driven over an artificial sediment bed using recirculating pumps. A high-resolution pulse-coherent acoustic Doppler profiler (Nortek Aquadopp HR) was used to measure vertical profiles of the three-dimensional mean current at different locations downstream of the model turbine. A three-dimensional Acoustic Ripple Profiler was used to map the bed and its evolution during the experiments. Acoustic backscatter systems were also deployed in two-dimensional arrays both along the flume and across the flume. These measurements revealed that the presence of the model turbine resulted in an expected reduction of the mean current and in changes in the vertical shear profiles. The bed mapping highlighted a horseshoe-shaped scour near the model turbine, and sediment deposition in the far wake region. The model turbine significantly influenced the suspension patterns, and generated significant asymmetry in the process, which was also evident from the other measurements (flow and sediment bed). These results highlight the effects induced by TSTs on near-bed hydrodynamics, suspension dynamics, and geomorphology, which may all have to be considered prior to large-scale deployments of arrays of TSTs in shelf seas.

  18. Investigations of Sediment Transportation, Middle Loup River at Dunning, Nebraska: With Application of Data from Turbulence Flume

    USGS Publications Warehouse

    Hubbell, David Wellington; Matejka, Donald Quintin

    1959-01-01

    An investigation of fluvial sediments of the Middle Loup River at Dunning, Nebr., was begun in 1946 and expanded in 1949 to provide information on sediment transportation. Construction of an artificial turbulence flume at which the total sediment discharge of the Middle Loup River at Dunning, Nebr., could be measured with suspended-sediment sampling equipment was completed in 1949. Since that time. measurements have been made at the turbulence flume and at several selected sections in a reach upstream and downstream from the flume. The Middle Loup River upstream from Dunning traverses the sandhills region of north-central Nebraska and has a drainage area of approximately 1,760 square miles. The sandhills are underlain by the Ogallala formation of Tertiary age and are mantled by loess and dune sand. The topography is characterized by northwest-trending sand dunes, which are stabilized by grass cover. The valley floor upstream from Dunning is generally about half a mile wide, is about 80 feet lower than the uplands, and is composed of sand that was mostly stream deposited. The channel is defined by low banks. Bank erosion is prevalent and is the source of most of the sediment load. The flow originates mostly from ground-water accretion and varies between about 200 and 600 cfs (cubic feet per second). Measured suspended-sediment loads vary from about 200 to 2,000 tons per day, of which about 20 percent is finer than 0.062 millimeter and 100 percent is finer than 0.50 millimeter. Total sediment discharges vary from about 500 to 3,500 tons per day, of which about 10 percent is finer than 0.062 millimeter, about 90 percent is finer than 0.50 millimeter, and about 98 percent is finer than 2.0 millimeters. The measured suspended-sediment discharge in the reach near Dunning averages about one-half of the total sediment discharge as measured at the turbulence flume. This report contains information collected during the period October 1, 1948, to September 30, 1952. The

  19. Investigation of erosion rates of field samples using FDOT's enhanced sediment erosion rate flume (SERF).

    DOT National Transportation Integrated Search

    2013-09-01

    The first part of this project was to enhance and improve the Florida Department of Transportations : Sediment Erosion Rate Flume (SERF) device. Notable improvements include a pump repair, laser : system enhancement, installation of a digital vide...

  20. Flume experiments on wind induced flow in static water bodies in the presence of protruding vegetation

    NASA Astrophysics Data System (ADS)

    Banerjee, Tirtha; Muste, Marian; Katul, Gabriel

    2015-02-01

    The problem of wind-induced flow in inland waters is drawing significant research attention given its relevance to a plethora of applications in wetlands including treatment designs, pollution reduction, and biogeochemical cycling. The present work addresses the role of wind induced turbulence and waves within an otherwise static water body in the presence of rigid and flexible emergent vegetation through flume experimentation and time series analysis. Because no prior example of Particle Imaging Velocimetry (PIV) experiments involving air-water and flexible oscillating components have been found in the literature, a spectral analysis framework is needed and proposed here to guide the analysis involving noise, wave and turbulence separation. The experiments reveal that wave and turbulence effects are simultaneously produced at the air-water interface and the nature of their coexistence is found to vary with different flow parameters including water level, mean wind speed, vegetation density and its flexibility. For deep water levels, signature of fine-scaled inertial turbulence is found at deeper layers of the water system. The wave action appears stronger close to the air-water interface and damped by the turbulence deeper inside the water system. As expected, wave action is found to be dominated in a certain frequency range driven by the wind forcing, while it is also diffused to lower frequencies by means of (wind-induced) oscillations in vegetation. Regarding the mean water velocity, existence of a counter-current flow and its switching to fully forward flow in the direction of the wind under certain combinations of flow parameters were studied. The relative importance of wave and turbulence to the overall energy, degree of anisotropy in the turbulent energy components, and turbulent momentum transport at different depths from the air-water interface and flow combinations were then quantified. The flume experiments reported here differ from previous laboratory

  1. The Role of Cyanobacteria in Stromatolite Morphogenesis, Highborn Cay Bahamas: An Integrated Field and Laboratory Simulation Study

    NASA Technical Reports Server (NTRS)

    Prufert-Bebout, Leslie; Shepard, Rebekah; Reid, Pamela R.; Fonda, Mark (Technical Monitor)

    2001-01-01

    Geomicrobiological phenomena are among the most fundamental of interactions between Earth and its biosphere. Actively growing and lithifying stromatolites at Highborne Cay Bahamas, have recently been documented and allow for detailed examination of the roles microbes play in the mineralization process. These stromatolites contain a variety of complex microbial communities with distinct distribution patterns for different microbial groups. Cyanobacteria are the primary producers in this system providing energy, directly or indirectly, for the entire stromatolite microbial community. They also play key roles in the trapping and binding of sediments. Most of these species are highly motile and can adjust their position and orientation within the sediment matrix in order to optimize their access to irradiance and nutrients. As individual species have different physical and metabolic properties, this motility generally results in segregated distributions of species, which in turn contributes to the laminated textures observed in these actively forming stromatolites. Increasingly our studies suggest that the activities and locations of various cyanobacterial species also contribute greatly to the localization of new mineral precipitation through a variety of processes. We are investigating these contributions using an integrated approach combining detailed observations of field samples with manipulative experiments using both field samples and cultures of specific organisms isolated from these stromatolites. Experiments are conducted both in standard laboratory conditions and in outdoor running seawater flumes. A variety of standard techniques; SEM (scanning electron microscopy), petrographic analyses, TEM (transmission electron microscopy), are used to compare mineralization processes in field samples with those generated in laboratory-flume simulations. Using this approach we are able to more thoroughly investigate the effects of irradiance, CaCO3 saturation, and

  2. Adjustable shear stress erosion and transport flume

    DOEpatents

    Roberts, Jesse D.; Jepsen, Richard A.

    2002-01-01

    A method and apparatus for measuring the total erosion rate and downstream transport of suspended and bedload sediments using an adjustable shear stress erosion and transport (ASSET) flume with a variable-depth sediment core sample. Water is forced past a variable-depth sediment core sample in a closed channel, eroding sediments, and introducing suspended and bedload sediments into the flow stream. The core sample is continuously pushed into the flow stream, while keeping the surface level with the bottom of the channel. Eroded bedload sediments are transported downstream and then gravitationally separated from the flow stream into one or more quiescent traps. The captured bedload sediments (particles and aggregates) are weighed and compared to the total mass of sediment eroded, and also to the concentration of sediments suspended in the flow stream.

  3. Flume tank studies to elucidate the fate and behavior of diluted bitumen spilled at sea.

    PubMed

    King, Thomas L; Robinson, Brian; Boufadel, Michel; Lee, Kenneth

    2014-06-15

    An economical alternative to conventional crudes, Canadian bitumen, harvested as a semi-liquid, is diluted with condensate to make it viable to transport by pipeline to coastal areas where it would be shipped by tankers to global markets. Not much is known about the fate of diluted bitumen (dilbit) when spilled at sea. For this purpose, we conducted dilbit (Access Western Blend; AWB and Cold Lake Blend; CLB) weathering studies for 13 days in a flume tank containing seawater. After six days of weathering, droplets detached from the AWB slick and were dense enough to sink in seawater. The density of CLB also increased, but at a slower rate compared to AWB, which was attributed to the high concentration of alkylated polycyclic aromatic hydrocarbons in it, which are more resistant to weathering. An empirical, Monod-type model was introduced and was found to closely simulate the increase in oil density with time. Such a model could be used within oil spill models. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Winnowing and Flocculation in Bio-physical Cohesive Substrate: A Flume Experimental and Estuarine Study

    NASA Astrophysics Data System (ADS)

    Ye, L.; Parsons, D. R.; Manning, A. J.

    2016-12-01

    Cohesive sediment, or mud, is ubiquitously found in most aqueous environments, such as coasts and estuaries. The study of cohesive sediment behaviors requires the synchronous description of mutual interactions of grains (e.g., winnowing and flocculation), their physical properties (e.g., grain size) and also the ambient water. Herein, a series of flume experiments (14 runs) with different substrate mixtures of sand-clay-EPS (Extracellular Polymeric Substrates: secreted by aquatic microorganisms) are combined with an estuarine field survey (Dee estuary, NW England) to investigate the behavior of suspensions over bio-physical cohesive substrates. The experimental results indicate that winnowing and flocculation occur pervasively in bio-physical cohesive flow systems. Importantly however, the evolution of the bed and bedform dynamics and hence turbulence production can be lower when cohesivity is high. The estuarine survey also revealed that the bio-physical cohesion provided by both the clay and microorganism fractions in the bed, that pervasively exists in many natural estuarine systems, plays a significant role in controlling the interactions between bed substrate and sediment suspension and deposition, including controlling processes such as sediment winnowing, flocculation and re-deposition. Full understanding of these processes are essential in advancing sediment transport modelling and prediction studies across natural estuarine systems and the work will report on an improved conceptual model for sediment sorting deposition in bio-physical cohesive substrates.

  5. Riparian Vegetation Effects on Near-Bank Turbulence During Overbank Flows: A Flume Experiment

    NASA Astrophysics Data System (ADS)

    McBride, M.; Thompson, D. M.; Owen, T. E.; Pearce, A. R.; Hession, W. C.; Rizzo, D.

    2005-12-01

    Measurements from a fixed-bed, Froude-scaled hydraulic model of a stream in northeastern Vermont demonstrated the importance of riparian vegetation effects on near-bank turbulence during overbank flood events. The prototype stream, a tributary to Sleepers River, increased in channel width within the last 40 years in response to passive reforestation of its riparian zone. Previous research has found that reaches of small streams with forested riparian zones are commonly wider that adjacent reaches with non-forested, or meadow, vegetation; however, the driving mechanisms for this morphologic difference are not fully explained. Flume experiments were performed to investigate near-bank turbulence as a mechanism for channel widening in response to reforestation. A 1:5 scale, simplified model of half a channel and its adjacent floodplain was constructed within a 6 m long recirculating flume. The test region was 3.7 m long and 0.9 m wide and oriented with the channel centerline at the flume wall. The channel bed slope was fixed at 0.03, and experiments were run at three discharges: 30, 33, and 36 l/s. Two types of riparian vegetation scenarios were simulated: forested, with rigid, randomly-distributed, wooden dowels, and non-forested, with synthetic grass carpeting. Three-dimensional velocities were measured with a Nortek Vectrino acoustic Doppler velocimeter at 41 different locations within the channel and floodplain at near-bed and 0.6-depth elevations. Observations of three-dimensional velocities and calculations of turbulent kinetic energy (TKE) showed significant differences between forested and non-forested runs. Results indicated that turbulence intensity, as quantified by TKE, roughly doubled throughout the channel and floodplain when forested vegetation was introduced. Given that sediment entrainment and transport can be amplified in flows with high turbulence intensity, our results demonstrated the potential for increased erosion during overbank flood events in

  6. Statistical description of flume experiments on mixed-size bed-load transport and bed armoring processes

    NASA Astrophysics Data System (ADS)

    Chen, D.; Zhang, Y.

    2008-12-01

    The objective of this paper is to describe the statistical properties of experiments on non-uniform bed-load transport as well as the mechanism of bed armoring processes. Despite substantial effort made over the last two decades, the ability to compute the bed-load flux in a turbulent system remains poor. The major obstacles include the poor understanding of the formation of armor lays on bed surfaces. Such a layer is much flow-resistible than the underlying material and therefore significantly inhibits sediment transport from the reach. To study the problem, we conducted a flume study for mixed sand/gravel sediments. We observed that aggregated sediment blocks were the most common characters in armor layers - the largest sizes resist hydraulic forces, while the smaller sizes add interlocking support and prevent loss of fine material through gaps between the larger particles. Fractional transport rates with the existing of armor layers were measured with time by sediment trapping method at the end of flume. To address the intermittent and time-varying behavior of bed-load transport during bed armoring processes, we investigated the probability distribution of the fractional bed-load transport rates, and the underlying dynamic model derived from the continuous time random walk framework. Results indicate that it is critical to consider the impact of armor layers when a flow is sufficient to move some of the finer particles and yet insufficient to move all the larger particles on a channel bed.

  7. Interactions of frazil and anchor ice with sedimentary particles in a flume

    USGS Publications Warehouse

    Kempema, E.W.; Reimnitz, E.; Clayton, J.R.; Payne, J.R.

    1993-01-01

    Frazil and anchor ice forming in turbulent, supercooled water have been studied extensively because of problems posed to man-made hydraulic structures. In spite of many incidental observations of interactions of these ice forms with sediment, their geologic effects remain unknown. The present flume study was designed to learn about the effects of salinity, current speed, and sediment type on sediment dynamics in supercooled water. In fresh-water, frazil ice formed flocs as large as 8 cm in diameter that tended to roll along a sandy bottom and collect material from the bed. The heavy flocs often came to rest in the shelter of ripples, forming anchor ice that subsequently was buried by migrating ripples. Burial compressed porous anchor ice into ice-bonded, sediment-rich masses. This process disrupts normal ripple cross-bedding and may produce unique sedimentary structures. Salt-water flocs were smaller, incorporated less bed load, and formed less anchor ice than their fresh-water counterparts. In four experiments, frazil carried a high sediment load only for a short period in supercooled salt water, but released it with slight warming. This suggests that salt-water frazil is either sticky or traps particles only while surrounded by supercooled water (0.05 to 0.1 ??C supercooling), a short-lived phase in simple, small tanks. Salt water anchor ice formed readily on blocks of ice-bonded sediment, which may be common in nature. The theoretical maximum sediment load in neutrally-buoyant ice/sediment mixture is 122 g/l, never reported in nature so far. The maximum sediment load measured in this laboratory study was 88 g/l. Such high theoretical and measured sediment concentrations suggest that frazil and anchor ice are important sediment transport agents in rivers and oceans. ?? 1993.

  8. Hydrograph Shape Controls Channel Morphology and Organization in a Sand-Gravel Flume

    NASA Astrophysics Data System (ADS)

    Hempel, L. A.; Grant, G.; Hassan, M. A.; Eaton, B. C.

    2016-12-01

    A fundamental research question in fluvial geomorphology is to understand what flows shape river channels. Historically, the prevailing view has been that channel dimensions adjust to a so-termed "dominant discharge", which is often approximated as the bankfull flow. But using a single flow to reference the geomorphic effectiveness of an entire flow regime discounts many observations showing that different flows control different channel processes. Some flows entrain fine sediment, some entrain the full size distribution of bed sediment; some destabilize or build bars, some erode the banks, and so forth. To explore the relation between the full flow regime and channel morphology, we conducted a series of flume experiments to examine how hydrographs with different shapes, durations, and magnitudes result in different degrees of channel organization, which we define in terms of the regularity, spacing and architecture of self-formed channel features, such as bed patches, geometry and spacing of bedforms, and channel planform. Our experiments were run in a 12m long adjustable-width flume that developed a self-formed meandering, pool-riffle pattern. We found that hydrograph shape does control channel organization. In particular, channels formed by hydrographs with slower rising limbs and broader peaks were more organized than those formed by flashier hydrographs. To become organized, hydrographs needed to exceed a minimum flow threshold, defined by the intensity of sediment transport; below which the channel lacked bedforms and a regular meander pattern. Above an upper flow threshold, bars became disorganized and the channel planform transitioned towards braiding. Field studies of channels with different flow regimes but located in a similar physiographic setting support our experimental findings. Taken together, this work points to the importance of the hydrograph as a fundamental control on channel morphology, and offers the prospect of better understanding how

  9. Design and Modification of an Installation Method to Stabilize Small Trapezoidal Flumes in Drainage Ditches

    Treesearch

    Charles A. Harrison; Susan O’Ney

    2002-01-01

    We developed procedures for installing prefabricated trapezoidal flumes in deep (10 to 12 feet) drainage ditches to monitor hydrologic functions and provide gauge locations for sampling discharge. Flows from the instrumented basins were generally low, but the ditches were occasionally subject to high flows caused by rain events of 2 to 3 inches or more. These high flow...

  10. Formation of Cyclic Steps due to the Surge-type Turbidity Currents in a Flume Experiment

    NASA Astrophysics Data System (ADS)

    Yokokawa, M.

    2016-12-01

    Supercritical turbidity currents often form crescentic step-like wavy structures, which have been found at the submarine canyons, and deltaic environments. Field observations of turbidity currents and seabed topography on the Squamish delta in British Columbia, Canada revealed that cyclic steps formed by the surge-type turbidity currents (e.g., Hughes Clarke et al., 2012a; 2012b; 2014). The high-density portion of the flow, which affects the sea floor morphology, lasted only 30-60 seconds. The questions arise if we can reconstruct paleo-flow condition from the morphologic features of these steps. We don't know answers right now because there have been no experiments about the formative conditions of cyclic steps due to the "surge-type" turbidity currents. Here we did preliminary experiments on the formation of cyclic steps due to the multiple surge-type density currents, and compare the morphology of the steps with those of Squamish delta. First of all, we measured wave length and wave height of each step from profiles of each channels of Squamish delta from the elevation data and calculated the wave steepness. Wave steepness of active steps ranges about 0.05 to 0.15, which is relatively larger compare with those of other sediment waves. And in general, wave steepness is larger in the proximal region. The experiments had been performed at Osaka Institute of Technology. A flume, which is 7.0 m long, 0.3 m deep and 2 cm wide, was suspended in a larger tank, which is 7.6 m long, 1.2 m deep and 0.3 m wide, filled with water. The inner flume tilted at 7 degrees. Mixture of salt water (1.17 g/cm3) and plastic particles (1.5 g/cm3, 0.1-0.18 mm in diameter), whose weight ratio is 10:1, poured into the upstream end of the inner flume from head tank for 5 seconds. Discharge of the mixture was 240mL/s, thus for 5seconds 1200mL of mixture was released into the inner flume. We made 130 surges. As a result, four steps were formed ultimately, which were moving toward upstream

  11. Evolution of Fine-Grained Channel Margin Deposits behind Large Woody Debris in an Experimental Gravel-Bed Flume

    NASA Astrophysics Data System (ADS)

    ONeill, B.; Marks, S.; Skalak, K.; Puleo, J. A.; Wilcock, P. R.; Pizzuto, J. E.

    2014-12-01

    Fine grained channel margin (FGCM) deposits of the South River, Virginia sequester a substantial volume of fine-grained sediment behind large woody debris (LWD). FGCM deposits were created in a laboratory setting meant to simulate the South River environment using a recirculating flume (15m long by 0.6m wide) with a fixed gravel bed and adjustable slope (set to 0.0067) to determine how fine sediment is transported and deposited behind LWD. Two model LWD structures were placed 3.7 m apart on opposite sides of the flume. A wire mesh screen with attached wooden dowels simulated LWD with an upstream facing rootwad. Six experiments with three different discharge rates, each with low and high sediment concentrations, were run. Suspended sediment was very fine grained (median grain size of 3 phi) and well sorted (0.45 phi) sand. Upstream of the wood, water depths averaged about 0.08m, velocities averaged about 0.3 m/s, and Froude numbers averaged around 0.3. Downstream of the first LWD structure, velocities were reduced tenfold. Small amounts of sediment passed through the rootwad and fell out of suspension in the area of reduced flow behind LWD, but most of the sediment was carried around the LWD by the main flow and then behind the LWD by a recirculating eddy current. Upstream migrating dunes formed behind LWD due to recirculating flow, similar to reattachment bars documented in bedrock canyon rivers partially obstructed by debouching debris fans. These upstream migrating dunes began at the reattachment point and merged with deposits formed from sediment transported through the rootwad. Downstream migrating dunes formed along the channel margin behind the LWD, downstream of the reattachment point. FGCM deposits were about 3 m long, with average widths of about 0.8 m. Greater sediment concentration created thicker FGCM deposits, and higher flows eroded the sides of the deposits, reducing their widths.

  12. Friction in debris flows: inferences from large-scale flume experiments

    USGS Publications Warehouse

    Iverson, Richard M.; LaHusen, Richard G.; ,

    1993-01-01

    A recently constructed flume, 95 m long and 2 m wide, permits systematic experimentation with unsteady, nonuniform flows of poorly sorted geological debris. Preliminary experiments with water-saturated mixtures of sand and gravel show that they flow in a manner consistent with Coulomb frictional behavior. The Coulomb flow model of Savage and Hutter (1989, 1991), modified to include quasi-static pore-pressure effects, predicts flow-front velocities and flow depths reasonably well. Moreover, simple scaling analyses show that grain friction, rather than liquid viscosity or grain collisions, probably dominates shear resistance and momentum transport in the experimental flows. The same scaling indicates that grain friction is also important in many natural debris flows.

  13. Wind Generated Rogue Waves in an Annular Wave Flume.

    PubMed

    Toffoli, A; Proment, D; Salman, H; Monbaliu, J; Frascoli, F; Dafilis, M; Stramignoni, E; Forza, R; Manfrin, M; Onorato, M

    2017-04-07

    We investigate experimentally the statistical properties of a wind-generated wave field and the spontaneous formation of rogue waves in an annular flume. Unlike many experiments on rogue waves where waves are mechanically generated, here the wave field is forced naturally by wind as it is in the ocean. What is unique about the present experiment is that the annular geometry of the tank makes waves propagating circularly in an unlimited-fetch condition. Within this peculiar framework, we discuss the temporal evolution of the statistical properties of the surface elevation. We show that rogue waves and heavy-tail statistics may develop naturally during the growth of the waves just before the wave height reaches a stationary condition. Our results shed new light on the formation of rogue waves in a natural environment.

  14. Streambed Mobility and Dispersal of Aquatic Insect Larvae: Results from a Laboratory Study.

    NASA Astrophysics Data System (ADS)

    Kenworthy, S. T.

    2002-12-01

    Three series of flume experiments were conducted to quantify relationships between entrainment of surface layer gravels and displacement of benthic insect larvae. One series (B) utilized a sediment mixture with a median size 6.9 mm, maximum size 45 mm, and 10% < 2mm. Two other series examined the effects of locally coarsening the bed surface (Bc) and increasing the < 2mm fraction to 20% (S). Aquatic insect larvae were collected in the field and placed in an upstream segment of the flume bed. Flow rate, flume slope, and sediment transport rate were varied systematically among experiments. Displaced larvae were collected in a net at the end of the flume. The distribution of larvae remaining in the bed was obtained by sorting larvae from the sediment in 25 channel segments. Flow rate and mean boundary shear stress varied among runs by factors of 1.2 and 2.4 respectively. Proportional entrainment of >11mm surface grains ranged from <0.05 to >0.90. Displacement of insect larvae increased in a regular and consistent manner with increasing flow strength and surface sediment entrainment. Significant displacement occurred for some types of larvae (Ephemerellid mayflies) over a relatively low range of shear stress and bed surface entrainment. Other larvae (Atherix sp.) were displaced only at the highest levels of bed surface entrainment. Displacement was lower from coarsened bed surfaces in series Bc, and higher from sandier sediments in series S experiments. The differential effects of bed surface entrainment upon various types of larvae are consistent with anatomical and behavioral differences that influence exposure to near-bed flow and bedload transport. These results suggest that spatial patterns of sediment mobilization are important for understanding patterns of dispersal and disturbance of streambed communities.

  15. Towing Tank and Flume Testing of Passively Adaptive Composite Tidal Turbine Blades: Preprint

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murray, Robynne; Ordonez-Sanchez, Stephanie; Porter, Kate E.

    Composite tidal turbine blades with bend-twist (BT) coupled layups allow the blade to self-adapt to local site conditions by passively twisting. Passive feathering has the potential to increase annual energy production and shed thrust loads and power under extreme tidal flows. Decreased hydrodynamic thrust and power during extreme conditions meann that the turbine support structure, generator, and other components can be sized more appropriately, resulting in a higher utilization factor and increased cost effectiveness. This paper presents new experimental data for a small-scale turbine with BT composite blades. The research team tested the turbine in the Kelvin Hydrodynamics Laboratory towingmore » tank at the University of Strathclyde in Glasgow, United Kingdom, and in the recirculating current flume at the l Institut Francais de Recherche pour l Exploitation de la Mer Centre in Boulogne-sur-Mer, France. Tests were also performed on rigid aluminum blades with identical geometry, which yielded baseline test sets for comparison. The results from both facilities agreed closely, supporting the hypothesis that increased blade flexibility can induce load reductions. Under the most extreme conditions tested the turbine with BT blades had up to 11 percent lower peak thrust loads and a 15 percent reduction in peak power compared to the turbine with rigid blades. The load reductions varied as a function of turbine rotational velocity and ambient flow velocity.« less

  16. Laboratory Studies of Wave Attenuation through Artificial and Real Vegetation

    DTIC Science & Technology

    2013-09-01

    33  Figure 35. Securing S. alterniflora in coir mats (left...alterniflora sections in the flume (left) with completed bed (right). ............. 39  Figure 42. Wave spectral transformation through coir control...44  Figure 45. Decay coefficient for S. alterniflora (N = 162 stems/m2) versus unplanted coir

  17. Engineering hyporheic zones to target nitrification versus denitrification: performance data from constructed stream flumes

    NASA Astrophysics Data System (ADS)

    Herzog, S.; Portmann, A. C.; Halpin, B. N.; Higgins, C.; McCray, J. E.

    2017-12-01

    Nonpoint source nitrogen pollution from agricultural and urban runoff is one of the leading causes of impairment to US rivers and streams. The hyporheic zone (HZ) offers a natural biogeochemical hotspot for the attenuation of nitrogen within streams, thereby complementing efforts to prevent aquatic nitrogen pollution in the first place. However, HZ in urban and agricultural streams are often degraded by scouring and colmation, which limit their potential to improve stream water quality at the reach scale. A recent effort to mitigate nitrogen pollution in the Chesapeake Bay region provides denitrification credits for hyporheic restoration projects. Unfortunately, many of the featured hyporheic zone best management practices (BMP) (e.g., weirs, cross-vanes) tend to create only localized, aerobic hyporheic flows that are not optimal for the anaerobic denitrification reaction. In short, practitioners lack an adaptable BMP that can both 1) increase hyporheic exchange, and 2) tailor HZ residence times to match reactions of interest. Here we present new performance data for an HZ engineering technique called Biohydrochemical Enhancements for Streamwater Treatment (BEST). BEST are subsurface modules that utilize low-permeability sediments to drive efficient hyporheic exchange and control residence times, along with reactive geomedia to increase reaction rates within HZ sediments. This research utilized two artificial stream flumes: One flume served as an all-sand control condition, the other featured BEST modules at 1m spacing with a mixture of 70/30 sand/woodchips (v/v). Two different BEST media were tested: a coarse sand module with K 0.5 cm/s, and a fine sand module with K 0.15 cm/s. The flume with coarse sand BEST modules created aerobic HZ conditions and demonstrated rapid nitrification of ammonia at rates significantly higher than the control. However, denitrification was much slower and not significantly different between the two streams. In contrast, the fine sand

  18. Spatial glyphosate and AMPA redistribution on the soil surface driven by sediment transport processes - A flume experiment.

    PubMed

    Bento, Célia P M; Commelin, Meindert C; Baartman, Jantiene E M; Yang, Xiaomei; Peters, Piet; Mol, Hans G J; Ritsema, Coen J; Geissen, Violette

    2018-03-01

    This study investigates the influence of small-scale sediment transport on glyphosate and AMPA redistribution on the soil surface and on their off-site transport during water erosion events. Both a smooth surface (T1) and a surface with "seeding lines on the contour" (T2) were tested in a rainfall simulation experiment using soil flumes (1 × 0.5 m) with a 5% slope. A dose of 178 mg m -2 of a glyphosate-based formulation (CLINIC ® ) was applied on the upper 0.2 m of the flumes. Four 15-min rainfall events (RE) with 30-min interval in between and a total rainfall intensity of 30 mm h -1 were applied. Runoff samples were collected after each RE in a collector at the flume outlet. At the end of the four REs, soil and sediment samples were collected in the application area and in four 20 cm-segments downslope of the application area. Samples were collected according to the following visually distinguished soil surface groups: light sedimentation (LS), dark sedimentation (DS), background and aggregates. Results showed that runoff, suspended sediment and associated glyphosate and AMPA off-site transport were significantly lower in T2 than in T1. Glyphosate and AMPA off-site deposition was higher for T2 than for T1, and their contents on the soil surface decreased with increasing distance from the application area for all soil surface groups and in both treatments. The LS and DS groups presented the highest glyphosate and AMPA contents, but the background group contributed the most to the downslope off-site deposition. Glyphosate and AMPA off-target particle-bound transport was 9.4% (T1) and 17.8% (T2) of the applied amount, while water-dissolved transport was 2.8% (T1) and 0.5% (T2). Particle size and organic matter influenced the mobility of glyphosate and AMPA to off-target areas. These results indicate that the pollution risk of terrestrial and aquatic environments through runoff and deposition can be considerable. Copyright © 2017 Elsevier Ltd

  19. Exploring the dynamic links between microbial ecology and redox state of the hyporheic zone: insight from flume experiments

    NASA Astrophysics Data System (ADS)

    Kaufman, M.; Cardenas, M. B.; Stegen, J.; Graham, E.; Cook, P. L. M.; Kessler, A. J.

    2016-12-01

    The hyporheic zone (HZ) provides key ecosystem services such as heavy metal sequestration, nutrient uptake and consumption, and habitat for a diverse collection of ecologically and commercially important species. Microbes are responsible for many of the chemical transformations in the HZ. These microbe populations are intimately linked to redox conditions, and recent work has shown that redox conditions in the HZ can be highly dynamic. Here we investigate the dynamic coupling between surface flow conditions, hyporheic redox conditions, and the hyporheic microbiome. Our window into this world is a large experimental flume (5m x 0.7m x 0.3m), prepared and incubated in a way that is relatively common to hyporheic zone research, without a strong attempt to impose a specific microbial community structure. We use computer-controlled flow combined with sand bedforms within the flume to generate a pattern of oxic and anoxic sediment zones, from which we collected sediment and water samples. Dissolved oxygen was mapped with a large planar optode. The samples were analyzed for microbial community composition through 16S rRNA gene sequencing. We compare the population structure between oxic and anoxic zones, showing that the presence of oxygen in the HZ is a strong predictor of microbial composition. Additionally, we compare both the oxic and anoxic community structure from the flume to those of samples taken from natural environments, showing both interesting similarities and differences. In the future, we plan to use time-series sampling to observe the response times of microbial communities subjected to dynamic surface channel flow and redox conditions. This work will yield greater understanding of the role that dynamic rivers play in microbe-provided ecosystem services.

  20. Exploring the dynamic links between microbial ecology and redox state of the hyporheic zone: insight from flume experiments

    NASA Astrophysics Data System (ADS)

    Kaufman, M.; Cardenas, M. B.; Stegen, J.; Graham, E.; Cook, P. L. M.; Kessler, A. J.

    2017-12-01

    The hyporheic zone (HZ) provides key ecosystem services such as heavy metal sequestration, nutrient uptake and consumption, and habitat for a diverse collection of ecologically and commercially important species. Microbes are responsible for many of the chemical transformations in the HZ. These microbe populations are intimately linked to redox conditions, and recent work has shown that redox conditions in the HZ can be highly dynamic. Here we investigate the dynamic coupling between surface flow conditions, hyporheic redox conditions, and the hyporheic microbiome. Our window into this world is a large experimental flume (5m x 0.7m x 0.3m), prepared and incubated in a way that is relatively common to hyporheic zone research, without a strong attempt to impose a specific microbial community structure. We use computer-controlled flow combined with sand bedforms within the flume to generate a pattern of oxic and anoxic sediment zones, from which we collected sediment and water samples. Dissolved oxygen was mapped with a large planar optode. The samples were analyzed for microbial community composition through 16S rRNA gene sequencing. We compare the population structure between oxic and anoxic zones, showing that the presence of oxygen in the HZ is a strong predictor of microbial composition. Additionally, we compare both the oxic and anoxic community structure from the flume to those of samples taken from natural environments, showing both interesting similarities and differences. In the future, we plan to use time-series sampling to observe the response times of microbial communities subjected to dynamic surface channel flow and redox conditions. This work will yield greater understanding of the role that dynamic rivers play in microbe-provided ecosystem services.

  1. Measuring the Bed Load velocity in Laboratory flumes using ADCP and Digital Cameras

    NASA Astrophysics Data System (ADS)

    Conevski, Slaven; Guerrero, Massimo; Rennie, Colin; Bombardier, Josselin

    2017-04-01

    Measuring the transport rate and apparent velocity of the bedload is notoriously hard and there is not a certain technique that would obtain continues data. There are many empirical models, based on the estimation of the shear stress, but only few involve direct measurement of the bed load velocity. The bottom tracking (BT) mode of an acoustic Doppler current profiler (ADCP) has been used many times to estimate the apparent velocity of the bed load. Herein is the basic idea, to exploit the bias of the BT signal towards the bed load movement and to calibrate this signal with traditional measuring techniques. These measurements are quite scarce and seldom reliable since there are not taken in controlled conditions. So far, no clear confirmation has been conducted in laboratory-controlled conditions that would attest the assumptions made in the estimation of the apparent bed load velocity, nor in the calibration of the empirical equations. Therefore, this study explores several experiments under stationary conditions, where the signal of the ADCP BT mode is recorded and compared to the bed load motion recorded by digital camera videography. The experiments have been performed in the hydraulic laboratories of Ottawa and Bologna, using two different ADCPs and two different high resolution cameras. In total, more then 30 experiments were performed for different sediment mixtures and different hydraulic conditions. In general, a good match is documented between the apparent bed load velocity measured by the ADCP and the videography. The slight deviation in single experiments can be explained by gravel particles inhomogeneity, difficult in reproducing the same hydro-sedimentological conditions and the randomness of the backscattering strength.

  2. Laminar laboratory rivers

    NASA Astrophysics Data System (ADS)

    Seizilles, Grégoire; Devauchelle, Olivier; Lajeunesse, Éric; Métivier, François

    2014-05-01

    A viscous fluid flowing over fine plastic grains spontaneously channelizes into a few centimeters-wide river. After reaching its equilibrium shape, this stable laboratory flume is able to carry a steady load of sediments, like many alluvial rivers. When the sediment discharge vanishes, the river size, shape and slope fit the threshold theory proposed by Glover and Florey (1951), which assumes that the Shields parameter is critical on the channel bed. As the sediment discharge is increased, the river widens and flattens. Surprisingly, the aspect ratio of its cross section depends on the sediment discharge only, regardless of the water discharge. We propose a theoretical interpretation of these findings based on the balance between gravity, which pulls particles towards the center of the channel, and the diffusion of bedload particles, which pushes them away from areas of intense bedload.

  3. Deciphering landslide behavior using large-scale flume experiments

    USGS Publications Warehouse

    Reid, Mark E.; Iverson, Richard M.; Iverson, Neal R.; LaHusen, Richard G.; Brien, Dianne L.; Logan, Matthew

    2008-01-01

    Landslides can be triggered by a variety of hydrologic events and they can exhibit a wide range of movement dynamics. Effective prediction requires understanding these diverse behaviors. Precise evaluation in the field is difficult; as an alternative we performed a series of landslide initiation experiments in the large-scale, USGS debris-flow flume. We systematically investigated the effects of three different hydrologic triggering mechanisms, including groundwater exfiltration from bedrock, prolonged rainfall infiltration, and intense bursts of rain. We also examined the effects of initial soil porosity (loose or dense) relative to the soil’s critical-state porosity. Results show that all three hydrologic mechanisms can instigate landsliding, but water pathways, sensor response patterns, and times to failure differ. Initial soil porosity has a profound influence on landslide movement behavior. Experiments using loose soil show rapid soil contraction during failure, with elevated pore pressures liquefying the sediment and creating fast-moving debris flows. In contrast, dense soil dilated upon shearing, resulting in slow, gradual, and episodic motion. These results have fundamental implications for forecasting landslide behavior and developing effective warning systems.

  4. A Laboratory Investigation of the Suspension, Transport, and Settling of Silver Carp Eggs Using Synthetic Surrogates

    PubMed Central

    Garcia, Tatiana; Zuniga Zamalloa, Carlo; Jackson, P. Ryan; Murphy, Elizabeth A.; Garcia, Marcelo H.

    2015-01-01

    Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter) as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this research study

  5. A laboratory investigation of the suspension, transport, and settling of silver carp eggs using synthetic surrogates

    USGS Publications Warehouse

    Garcia, Tatiana; Zuniga Zamalloa, Carlo; Jackson, P. Ryan; Murphy, Elizabeth A.; Garcia, Marcelo H.

    2015-01-01

    Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter) as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this research study

  6. Laboratory modeling of edge wave generation over a plane beach by breaking waves

    NASA Astrophysics Data System (ADS)

    Abcha, Nizar; Ezersky, Alexander; Pelinovsky, Efim

    2015-04-01

    Edge waves play an important role in coastal hydrodynamics: in sediment transport, in formation of coastline structure and coastal bottom topography. Investigation of physical mechanisms leading to the edge waves generation allows us to determine their effect on the characteristics of spatially periodic patterns like crescent submarine bars and cusps observed in the coastal zone. In the present paper we investigate parametric excitation of edge wave with frequency two times less than the frequency of surface wave propagating perpendicular to the beach. Such mechanism of edge wave generation has been studied previously in a large number of papers using the assumption of non-breaking waves. This assumption was used in theoretical calculations and such conditions were created in laboratory experiments. In the natural conditions, the wave breaking is typical when edge waves are generated at sea beach. We study features of such processes in laboratory experiments. Experiments were performed in the wave flume of the Laboratory of Continental and Coast Morphodynamics (M2C), Caen. The flume is equipment with a wave maker controlled by computer. To model a plane beach, a PVC plate is placed at small angle to the horizontal bottom. Several resistive probes were used to measure characteristics of waves: one of them was used to measure free surface displacement near the wave maker and two probes were glued on the inclined plate. These probes allowed us to measure run-up due to parametrically excited edge waves. Run-up height is determined by processing a movie shot by high-speed camera. Sub-harmonic generation of standing edge waves is observed for definite control parameters: edge waves represent themselves a spatial mode with wavelength equal to double width of the flume; the frequency of edge wave is equal to half of surface wave frequency. Appearance of sub-harmonic mode instability is studied using probes and movie processing. The dependence of edge wave exponential

  7. Experimental investigation of the wake behind a model of wind turbine in a water flume

    NASA Astrophysics Data System (ADS)

    Okulov, V. L.; Naumov, I. N.; Kabardin, I.; Mikkelsen, R.; Sørensen, J. N.

    2014-12-01

    The flow behind the model of wind turbine rotor is investigated experimentally in a water flume using Particle Image Velocimetry. The study carried out involves rotors of three bladed wind turbine designed using Glauert's optimization. The transitional regime, generally characterized as in between the regime governed by stable organized vortical structures and the turbulent wake, develops from disturbances of the tip and root vorticies through vortex paring and further complex behaviour towards the fully turbulent wake. Our PIV measurements pay special attention to the onset of the instabilities. The near wake characteristics (development of expansion, tip vortex position, deficit velocity and rotation in the wake) have been measured for different tip speed ratio to compare with main assumptions and conclusions of various rotor theories.

  8. Bedforms induced by solitary waves: laboratory studies on generation and migration rate

    NASA Astrophysics Data System (ADS)

    la Forgia, Giovanni; Adduce, Claudia; Falcini, Federico; Paola, Chris

    2017-04-01

    This study presents experiments on the formation of sandy bedforms, produced by surface solitary waves (SSWs) in shallow water conditions. The experiments were carried out in a 12.0 m long, 0.15 m wide and 0.5 m high flume, at Saint Anthony Falls Laboratory in Minneapolis. The tank is filled by fresh water and a removable gate, placed at the left hand-side of the tank, divides the flume in two regions: the lock region and the ambient fluid region. The standard lock-release method generates SSWs by producing a displacement between the free surfaces that are divided by the gate. Wave amplitude, wavelength, and celerity depend on the lock length and on the water level difference between the two regions. Natural sand particles (D50=0.64) are arranged on the bottom in order to form a horizontal flat layer with a thickness of 2 cm. A digital pressure gauge and a high-resolution acoustic velocimeter allowed us to measure, locally, both pressure and 3D water velocity induced on the bottom by each wave. Image analysis technique is then used to obtain the main wave features: amplitude, wavelength, and celerity. Dye is finally used as vertical tracer to mark the horizontal speed induced by the wave. For each experiment we generated 400 waves, having the same features and we analyzed their action on sand particles placed on the bottom. The stroke, induced by each wave, entails a shear stress on the sand particles, causing sediment transport in the direction of wave propagation. Immediately after the wave passage, a back flow occurs near the bottom. The horizontal pressure gradient and the velocity field induced by the wave cause the boundary layer separation and the consequent reverse flow. Depending on the wave features and on the water depth, the boundary shear stress induced by the reverse flow can exceed the critical value inducing the back motion of the sand particles. The experiments show that the particle back motion is localized at particular cross sections along the

  9. Short-term transport of glyphosate with erosion in Chinese loess soil--a flume experiment.

    PubMed

    Yang, Xiaomei; Wang, Fei; Bento, Célia P M; Xue, Sha; Gai, Lingtong; van Dam, Ruud; Mol, Hans; Ritsema, Coen J; Geissen, Violette

    2015-04-15

    Repeated applications of glyphosate may contaminate the soil and water and threaten their quality both within the environmental system and beyond it through water erosion related processes and leaching. In this study, we focused on the transport of glyphosate and its metabolite aminomethylphosphonic acid (AMPA) related to soil erosion at two slope gradients (10 and 20°), two rates of pesticide with a formulation of glyphosate (Roundup®) application (360 and 720 mg m(-2)), and a rain intensity of 1.0 mm min(-1) for 1 h on bare soil in hydraulic flumes. Runoff and erosion rate were significantly different within slope gradients (p<0.05) while suspended load concentration was relatively constant after 15 min of rainfall. The glyphosate and AMPA concentration in the runoff and suspended load gradually decreased. Significant power and exponent function relationship were observed between rainfall duration and the concentration of glyphosate and AMPA (p<0.01) in runoff and suspended load, respectively. Meanwhile, glyphosate and AMPA content in the eroded material depended more on the initial rate of application than on the slope gradients. The transport rate of glyphosate by runoff and suspended load was approximately 14% of the applied amount, and the chemicals were mainly transported in the suspended load. The glyphosate and AMPA content in the flume soil at the end of the experiment decreased significantly with depth (p<0.05), and approximately 72, 2, and 3% of the applied glyphosate (including AMPA) remained in the 0-2, 2-5, and 5-10 cm soil layers, respectively. The risk of contamination in deep soil and the groundwater was thus low, but 5% of the initial application did reach the 2-10 cm soil layer. The risk of contamination of surface water through runoff and sedimentation, however, can be considerable, especially in regions where rain-induced soil erosion is common. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Measurement of filtration rates by infaunal bivalves in a recirculating flume

    USGS Publications Warehouse

    Cole, B.E.; Thompson, J.K.; Cloern, J.E.

    1992-01-01

    A flume system and protocol for measuring the filtration rate of infaunal bivalves is described. Assemblages of multi-sized clams, at natural densities and in normal filter-feeding positions, removed phytoplankton suspended in a unidirectional flow of water. The free-stream velocity and friction velocity of the flow, and bottom roughness height were similar to those in natural estuarine waters. Continuous variations in phytoplankton (Chroomonas salinay) cell density were used to measure the filtration rate of the suspension-feeding clam Potamocorbula amurensis for periods of 2 to 28 h. Filtration rates of P. amurensis varied from 100 to 580 liters (gd)-1 over a free-stream velocity range of 9 to 25 cm s-1. Phytoplankton loss rates were usually constant throughout the experiments. Our results suggest that suspension-feeding by infaunal bivalves is sensitive to flow velocity. ?? 1992 Springer-Verlag.

  11. Persistence of Escherichia coli O157:H7 during pilot-scale processing of iceberg lettuce using flume water containing peroxyacetic acid-based sanitizers and various organic loads.

    PubMed

    Davidson, Gordon R; Kaminski-Davidson, Chelsea N; Ryser, Elliot T

    2017-05-02

    In order to minimize cross-contamination during leafy green processing, chemical sanitizers are routinely added to the wash water. This study assessed the efficacy of peroxyacetic acid and mixed peracid against E. coli O157:H7 on iceberg lettuce, in wash water, and on equipment during simulated commercial production in a pilot-scale processing line using flume water containing various organic loads. Iceberg lettuce (5.4kg) inoculated to contain 10 6 CFU/g of a 4-strain cocktail of non-toxigenic, GFP-labeled, ampicillin-resistant E. coli O157:H7, was shredded using a commercial shredder, step-conveyed to a flume tank, washed for 90s using water alone or two different sanitizing treatments (50ppm peroxyacetic acid or mixed peracid) in water containing organic loads of 0, 2.5, 5 or 10% (w/v) blended iceberg lettuce, and then dried using a shaker table and centrifugal dryer. Thereafter, three 5.4-kg batches of uninoculated iceberg lettuce were identically processed. Various product (25g) and water (50ml) samples collected during processing along with equipment surface samples (100cm 2 ) from the flume tank, shaker table and centrifugal dryer were then assessed for numbers of E. coli O157:H7. Organic load rarely impacted (P>0.05) the efficacy of either peroxyacetic acid or mixed peracid, with typical reductions of >5logCFU/ml in wash water throughout processing for all organic loads. Increases in organic load in the wash water corresponded to changes in total solids, chemical oxygen demand, turbidity, maximum filterable volume, and oxidation/reduction potential. After 90s of exposure to flume water, E. coli O157:H7 reductions on inoculated lettuce ranged from 0.97 to 1.74logCFU/g using peroxyacetic acid, with an average reduction of 1.35logCFU/g for mixed peracid. E. coli O157:H7 persisted on all previously uninoculated lettuce following the inoculated batch, emphasizing the need for improved intervention strategies that can better ensure end-product safety. Copyright

  12. Evaluation of the Ott Hydromet Qliner for measuring discharge in laboratory and field conditions

    USGS Publications Warehouse

    McVay, Jason C.

    2015-01-01

    The U.S. Geological Survey, in collaboration with the University of Iowa IIHR – Hydroscience and Engineering, evaluated the use of the Ott Hydromet Qliner using laboratory flume tests along with field validation tests. Analysis of the flume testing indicates the velocities measured by the Qliner at a 40-second exposure time results in higher dispersion of velocities from the mean velocity of data collected with a 5-minute exposure time. The percent data spread from the mean of a 100-minute mean of Qliner velocities for a 40-second exposure time averaged 16.6 percent for the entire vertical, and a 5-minute mean produced a 6.2 percent data spread from the 100-minute mean. This 16.6 percent variation in measured velocity would result in a 3.32 percent variation in computed discharge assuming 25 verticals while averaging 4 bins in each vertical. The flume testing also provided results that indicate the blanking distance of 0.20 meters is acceptable when using beams 1 and 2, however beam 3 is negatively biased near the transducer and the 0.20-meter blanking distance is not sufficient. Field testing included comparing the measured discharge by the Qliner to the discharge measured by a Price AA mechanical current meter and a Teledyne RDI Rio Grande 1200 kilohertz acoustic Doppler current profiler. The field tests indicated a difference between the discharges measured with the Qliner and the field reference discharge between -14.0 and 8.0 percent; however the average percent difference for all 22 field comparisons was 0.22, which was not statistically significant.

  13. Investigating the effects of transport on the preservation of soft-bodied organisms using an annular flume tank.

    NASA Astrophysics Data System (ADS)

    Bath Enright, Orla; Minter, Nicholas; Sumner, Esther; Mángano, Gabriela; Buatois, Luis

    2016-04-01

    Annular flume tank experiments offer unique opportunities to be able to investigate the effect of transport on a range of organisms; being able to create slow to fast sediment-laden flows that can be laminar to fully turbulent, and lasting over durations of minutes to hours. Understanding the effects of transport on the preservation potential of different organisms is fundamental to the study of palaeoecology. Despite this, the sedimentological processes leading up to fossil entombment remain largely overlooked. This is especially significant for fossil lagerstätte such as the Burgess Shale, whose exquisite fossil preservation has enabled insights into the anatomy of early soft-bodied organisms and their evolution during the Cambrian explosion. However there is still a fundamental debate with regards to the transport these organisms have undergone. Namely, whether they were living within or close to the environment of deposition, or could they have been transported from one environment to another? As such, does the Burgess Shale biota represent a palaeocommunity or not? To explore the limits of the effect of transport, initial experiments have been designed using an annular flume tank in order to test the influence of fully turbulent sandy suspensions (75-250μm) on organism preservation. This is a three factorial design where the three independent variables are transport duration, sediment concentration and grain angularity. In all experiments, flow velocity was kept constant along with controls on pH and salinity. The dependent variable, an index of "increasing state of damage" has been devised to classify the amount of destruction each organism exhibits after the experimental procedure. Results are presented here. From observations such as these, we can begin to set constraints on the amount of transport, if any, that these fossil organisms could have endured.

  14. Measuring Ucrit and endurance: equipment choice influences estimates of fish swimming performance.

    PubMed

    Kern, P; Cramp, R L; Gordos, M A; Watson, J R; Franklin, C E

    2018-01-01

    This study compared the critical swimming speed (U crit ) and endurance performance of three Australian freshwater fish species in different swim-test apparatus. Estimates of U crit measured in a large recirculating flume were greater for all species compared with estimates from a smaller model of the same recirculating flume. Large differences were also observed for estimates of endurance swimming performance between these recirculating flumes and a free-surface swim tunnel. Differences in estimates of performance may be attributable to variation in flow conditions within different types of swim chambers. Variation in estimates of swimming performance between different types of flumes complicates the application of laboratory-based measures to the design of fish passage infrastructure. © 2017 The Fisheries Society of the British Isles.

  15. Morphodynamics of semi-alluvial streams in northern Fennoscandia: a flume experiment to determine bedform self-organization

    NASA Astrophysics Data System (ADS)

    Polvi, Lina

    2017-04-01

    Streams in northern Fennoscandia have two characteristics that complicate a process-based understanding of sediment transport affecting channel form: (1) they are typically semi-alluvial, in that they contain coarse glacial legacy sediment, and (2) numerous mainstem lakes buffer sediment and water fluxes. Systematic studies of these streams are complicated because natural reference sites are lacking due to over a century of widespread channel simplification to aid timber-floating. This research is part of a larger project to determine controls on channel geometry and sediment transport at: (1) the catchment scale, examining downstream hydraulic geometry, (2) the reach scale, examining sediment transport, and (3) the bedform scale, examining the potential for predictable bedform formation. The objective of the current study, targeting the bedform scale, was to use a flume experiment to determine whether sediment self-organizes and creates bedforms in semi-alluvial channels. The prototype channels, tributaries to the unregulated Vindel River in northern Sweden that are being restored after timber-floating, contain coarse sediment (D16: 55 mm, D50:250 mm, D84:620 mm) with moderately steep slopes (2-5%) and typically experience snowmelt-flooding and flooding due to ice jams. Using a scaling factor of 8 for Froude number similitude, an 8-m long, 1.1 m wide fixed-bed flume was set up at the Colorado State University Engineering Research Center with a scaled-down sediment distribution analogous to the prototype channels. For two flume setups, with bed slopes of 2% and 5%, four runs were conducted with flows analogous to QBF, Q2, Q10 and Q50 flows in the prototype channels until equilibrium conditions were reached. Digital elevation models (DEMs) of bed topography were constructed before and after each run using structure-from-motion photogrammetry. To examine self-organization of sediment, DEMs of difference between pre-flow conditions and after each flow were created

  16. Resistance to uprooting of Alfalfa and Avena Sativa and related importance for flume experiments

    NASA Astrophysics Data System (ADS)

    Edmaier, K.; Crouzy, B.; Burlando, P.; Perona, P.

    2012-04-01

    Vegetation influences sediment dynamics by stabilizing the alluvial sediment with its root system. Thus, vegetation engineers the riparian ecosystem by contributing to the formation and stabilization of river bars and islands. The resistance to uprooting of young plants in non-cohesive sediment depends on the competition between flow induced drag and root growth timescales. The investigation of flow-sediment-plant interactions in situ is difficult since variables cannot be controlled and material hardly be collected. In order to investigate ecomorphological processes, laboratory experiments are essential and have gained importance in the last decade. To achieve a better understanding of the dependence of resistance to uprooting on the root system (length and structure) we conducted vertical uprooting experiments with Alfalfa and Avena Sativa which are both species that have been used in flume experiments on vegetation-flow interactions (e.g. Tal and Paola, 2010; Perona et al., in press). Seeds were seeded on quartz sand and vertically uprooted with constant velocity whereat the weight force required to uproot a seedling was measured. After uprooting, roots were scanned and analyzed and the correlation of root parameters with the uprooting work was studied. Total root length was found to be the best explanatory variable, in particular the uprooting work increases following a power law with increasing root length. The impact of other root parameters (main root length, root number, tortuosity) on the uprooting work was as well analyzed. Still, not all influencing root parameters could be captured, like the angle between roots or root hair distribution. Environmental conditions like grain size and saturation were also found to have an effect on the uprooting resistance of roots. So, lower saturated sediment results in a higher uprooting work. This work is a first step to better understand the energy regime for vegetation uprooting and its dependence on various

  17. Characteristics of sediment resuspension in Lake Taihu, China: A wave flume study

    NASA Astrophysics Data System (ADS)

    Ding, Yanqing; Sun, Limin; Qin, Boqiang; Wu, Tingfeng; Shen, Xia; Wang, Yongping

    2018-06-01

    Lake Taihu is a typical shallow lake which frequently happens sediment resuspension induced by wind-induced waves. The experiments are carried on to simulate the wave disturbance processes in wave flume by setting a series of wave periods (1.2 s, 1.5 s, 1.8 s) and wave heights (2 cm, 10 cm). It aims to analyze the characteristics of sediment resuspension and the mechanisms of nutrients release and to evaluate the effects of sediment dredging on sediment resuspension and nutrients release in Lake Taihu. The results show that wave shear stress during 2 cm and 10 cm wave height processes ranges 0.018-0.023 N/m2 and 0.221-0.307 N/m2, respectively. Wave shear stress has no significant differences between wave periods. Wave height has much more effects on sediment resuspension. Wave height of 2 cm could induce total suspended solids (TSS) reaching up to 5.21 g/m2 and resuspension flux of sediment (M) up to 1.74 g/m2. TSS sharply increases to 30.33-52.41 g/m2 and M reached up to 48.94 g/m2 when wave height reaches to 10 cm. The disturbance depth under different sediment bulk weights ranges from 0.089 to 0.161 mm. Variation of suspended solids in 3 layers (1 cm, 5 cm, 20 cm above sediment interface) has no significant differences. Organic matter, TN and TP have positive relationship with SS. Organic matter is only accounted for 5.7%-7.3% of SS. The experiments under different sediment bulk densities (1.34 g/cm3, 1.47 g/cm3 and 1.59 g/cm3) find that TSS and M fall by 44.2% and 39.8% with sediment bulk density increasing, respectively. Total TN, DTN, TP and DTP decrease by 24.3%-33.6%. It indicates that sediment dredging could effectively reduce SS concentration and nutrient levels in water column. The researches provide a theoretical basis for sediment dredging to control the shore zone of Lake Taihu for lake management.

  18. Culvert roughness elements for native Utah fish passage : phase I.

    DOT National Transportation Integrated Search

    2011-01-01

    Laboratory flume testing of native Utah non-salmonid fish was performed to observe how : they use altered flow around obstacles to swim upstream. Three experimental setups included : a bare Plexiglas flume, vertical cylinders, and natural substrate p...

  19. Exploratory laboratory study of lateral turbulent diffusion at the surface of an alluvial channel

    USGS Publications Warehouse

    Sayre, William W.; Chamberlain, A.R.

    1964-01-01

    In natural streams turbulent diffusion is one of the principal mechanisms by which liquid and suspended-particulate contaminants are dispersed in the flow. A knowledge of turbulence characteristics is therefore essential in predicting the dispersal rates of contaminants in streams. In this study the theory of diffusion by continuous movements for homogeneous turbulence is applied to lateral diffusion at the surface of an open channel in which there is uniform flow. An exploratory-laboratory investigation was conducted in which the lateral dispersion at the water surface of a sand-Led flume was studied by measuring the lateral spread from a point source of small floating polyethylene articles. The experiment was restricted to a single set of low and channel geometry conditions. The results of the study indicate that with certain restrictions lateral dispersion in alluvial channels may be successfully described by the theory of diffusion by continuous movements. The experiment demonstrates a means for evaluating the lateral diffusion coefficient and also methods for quantitatively estimating fundamental turbulence properties, such as the intensity and the Lagrangian integral scale of turbulence in an alluvial channel. The experimental results show that with increasing distance from the source the coefficient of lateral turbulent diffusion increases initially but tends toward a constant limiting value. This result is in accordance with turbulent diffusion theory. Indications are that the distance downstream from the source required for the diffusion coefficient to reach its limiting value is actually very small when compared to the length scale of most diffusion phenomena in natural streams which are of practical interest.

  20. Wave-flume experiments of soft-rock cliff erosion under monochromatic waves

    NASA Astrophysics Data System (ADS)

    Regard, Vincent; Astruc, Dominique; Caplain, Bastien

    2017-04-01

    We investigate how cliffs erode under wave attack. Rocky coast erosion works through cycles, each one corresponding to three successive phases: (i) notch creation at cliff toe by mechanical action of waves, (ii) cliff fracturation leading to collapse, and (iii) evacuation of scree aprons by waves and currents. We performed experiments in a 5m x 14cm x 25cm wave flume (15 cm water depth) to investigate how waves are eroding a rocky coast. The cliff is made of wet sand and models a relatively soft rock. We used 3 different grain size (D50 = 0.28-0.41-0.48 mm), changing the cliff rheology. Waves are monochromatic; their height and period differ for the various experiments. Actual wave parameters are estimated by capacitive probes located offshore. The experiments are monitored by two video cameras both on the side and above the flume. Pictures are taken at a rate of 1Hz during the first 4h and then the rate is decreased to 0.1Hz till the end of experiment (about 1 day). The monitoring ensure a confident characterization of experiments in terms of waves (surf similarity parameter ξ and the incident wave energy flux F) and in terms of sediment (Dean number Ω and Shields number θb at breakers). Experiments begin by an initial phase of quick cliff retreat. Then the system evolves with slower cliff retreat. We focus on bottom morphology which we characterize in function of wave forcing (ξ, F). We show that the bottom morphology mainly depends on ξ. For our reference sediment (Dm = 0.41 mm), we observed: (i) surging breakers on a steep terrace (type T1) for ξ > 0.65; (ii)collapsing breakers on a bared profile attached to the inner platform (type T2) for 0.55< ξ <0.6; (iii) spilling breakers on gentle terrace (type T3) for F < 1.3 W/m and 0.55< ξ <0.6. Another bottom morphology, type T4, displays two sub-systems, an outer system with a double-bar profile where breaking waves are plunging, and an inner system with a T1, T2 or T3 profile. Some of these bottom

  1. Effectiveness of distinct mulch application rates and schemes under laboratory conditions

    NASA Astrophysics Data System (ADS)

    Prats, Sergio; Abrantes, Joao; Crema, Isabela; Keizer, Jacob; de Lima, Joao

    2017-04-01

    Post-fire forest residue mulching using eucalypt bark strands have been proven effective for reducing hillslope runoff and erosion in field plots of different sizes. Application rates of around 8-10 Mg ha-1 achieved about 80% of protective soil surface. Lower application rates, however, would reduce costs and, possibly, also allow faster application, which could be especially critical in late summer high-severity fires. Such lower rates could be achieved by applying less mulch per unit area, by applying mulch in specific zones (strips) and by removing the finest fractions, especially since these can be expected to contribute little to reduce erosion risk. The objective of this laboratory study was to identify the threshold, or the minimum application rate, at which a new mulch blend (without the fraction ≤4 cm) would effectively control runoff and erosion. Two levels of ground cover by forest residue mulch (50 and 70%) and three mulch strips (of 1/3, 2/3 and 3/3) at the bottom of the flume were tested against the untreated bare soil, by applying simulated rainfall and simulated inflow. The seven treatments were replicated three times using a 2.7 m x 0.3 m soil flume with a 40% slope, filled with a dry loamy sand soil. Each experiment included: (i) a "Dry" soil run comprising 20 min of simulated rainfall at a rate of 56 mm h-1; (ii) a "Wet" soil run with the same rainfall characteristics; (iii) a "Flow" run combining 20 min of rainfall with three inflows at increasing rates (52, 110, 232 mm h-1) on nearly saturated soil. The results showed that runoff, interrill and rill erosion were strongly reduced by covering 3/3 and 2/3 of the flume with mulch at 70% ground cover (overall mulch application rates of 2.6 and 1.3 Mg ha-1). The 1/3 mulch strip at 70% mulch cover (application rate of 1 Mg ha-1) also reduced significantly erosion but not runoff. The mulch strips at 50% were less effective, and only the application over the whole plot was able to reduce interrill and

  2. Sprinting performance of two Iberian fish: Luciobarbus bocagei and Pseudochondrostoma duriense in an open channel flume

    USGS Publications Warehouse

    Sanz-Ronda, Francisco Javier; Ruiz-Legazpi, Jorge; Bravo-Cordoba, Francisco Javier; Makrakis, Sergio; Castro-Santos, Theodore R.

    2015-01-01

    This paper presents sprinting data from Iberian barbel (Luciobarbus bocagei) and northern straight-mouth nase (Pseudochondrostoma duriense), volitionally swimming against high velocity flows (1.5, 2.5 and 3 m s−1) in an open channel flume. Swimming endurance and speed greatly exceeded previously published observations with both species attaining swim speeds >20 body lengths s−1. Flow velocity was the primary variable limiting the distance both species were able to traverse. Barbel swam greater distances than nase at higher flow velocities, with longer individuals attaining greater distances than smaller ones. The results challenge established fish passage guidelines, suggesting that in some cases these species are capable of passing much higher velocities than was previously believed.

  3. Field and laboratory determination of water-surface elevation and velocity using noncontact measurements

    USGS Publications Warehouse

    Nelson, Jonathan M.; Kinzel, Paul J.; Schmeeckle, Mark Walter; McDonald, Richard R.; Minear, Justin T.

    2016-01-01

    Noncontact methods for measuring water-surface elevation and velocity in laboratory flumes and rivers are presented with examples. Water-surface elevations are measured using an array of acoustic transducers in the laboratory and using laser scanning in field situations. Water-surface velocities are based on using particle image velocimetry or other machine vision techniques on infrared video of the water surface. Using spatial and temporal averaging, results from these methods provide information that can be used to develop estimates of discharge for flows over known bathymetry. Making such estimates requires relating water-surface velocities to vertically averaged velocities; the methods here use standard relations. To examine where these relations break down, laboratory data for flows over simple bumps of three amplitudes are evaluated. As anticipated, discharges determined from surface information can have large errors where nonhydrostatic effects are large. In addition to investigating and characterizing this potential error in estimating discharge, a simple method for correction of the issue is presented. With a simple correction based on bed gradient along the flow direction, remotely sensed estimates of discharge appear to be viable.

  4. Numerical simulation of failure behavior of granular debris flows based on flume model tests.

    PubMed

    Zhou, Jian; Li, Ye-xun; Jia, Min-cai; Li, Cui-na

    2013-01-01

    In this study, the failure behaviors of debris flows were studied by flume model tests with artificial rainfall and numerical simulations (PFC(3D)). Model tests revealed that grain sizes distribution had profound effects on failure mode, and the failure in slope of medium sand started with cracks at crest and took the form of retrogressive toe sliding failure. With the increase of fine particles in soil, the failure mode of the slopes changed to fluidized flow. The discrete element method PFC(3D) can overcome the hypothesis of the traditional continuous medium mechanic and consider the simple characteristics of particle. Thus, a numerical simulations model considering liquid-solid coupled method has been developed to simulate the debris flow. Comparing the experimental results, the numerical simulation result indicated that the failure mode of the failure of medium sand slope was retrogressive toe sliding, and the failure of fine sand slope was fluidized sliding. The simulation result is consistent with the model test and theoretical analysis, and grain sizes distribution caused different failure behavior of granular debris flows. This research should be a guide to explore the theory of debris flow and to improve the prevention and reduction of debris flow.

  5. Field and flume investigations of the effects of logjams and woody debris on streambed morphology

    NASA Astrophysics Data System (ADS)

    Leung, V.; Montgomery, D. R.; McHenry, M. L.

    2014-12-01

    Interactions among wood debris, fluid flow and sediment transport in rivers are first-order controls on channel morphodynamics, affecting streambed morphology, sediment transport, sediment storage and aquatic habitat. Woody debris increases the hydraulic and topographic complexity in rivers, leading to a greater diversity of aquatic habitats and an increase in the number of large pools that are important fish habitat and breeding grounds. In the past decade, engineered logjams have become an increasingly used tool in river management for simultaneously decreasing the rate of riverbank migration and improving aquatic habitat. Sediment deposits around woody debris build up riverbanks and counteract bank migration caused by erosion. Previous experiments on flow visualization around model woody debris suggest the amount of sediment scour and deposition are primarily related to the presence of roots and the obstructional area of the woody debris. We present the results of fieldwork and sediment transport experiments of streambed morphology around stationary woody debris. Field surveys on the Hoh River and the Elwha River, WA, measure the local streambed morphology around logjams and individual pieces of woody debris. We quantified the amount of local scour and dam-removal related fine sediment deposition around natural and engineered logjams of varying sizes and construction styles, located in different geomorphic settings. We also quantified the amount of local scour around individual pieces of woody debris of varying sizes, geometries and orientations relative to flow. The flume experiments tested the effects of root geometry and log orientation of individual stationary trees on streambed morphology. The flume contained a deformable sediment bed of medium sand. We find that: 1) the presence of roots on woody debris leads to greater areas of both sediment scour and deposition; and 2) the amount of sediment scour and deposition are related to the wood debris cross

  6. The use of an in situ portable flume to examine the effect of flow properties on the capture probability of juvenile Atlantic salmon

    NASA Astrophysics Data System (ADS)

    Roy, M. L.; Roy, A. G.; Grant, J. W.

    2013-12-01

    For stream fish, flow properties have been shown to influence energy expenses and habitat selection. Furthermore, flow properties directly influence the velocity of drifting prey items, therefore influencing the probability of fish at catch prey. Flow properties might also have an effect on prey trajectories that can become more unpredictable with increased turbulence. In this study, we combined field and experimental approaches to examine the foraging behaviour and position choice of juvenile Atlantic salmon in various flow conditions. We used an in situ portable flume, which consists in a transparent enclosure (observation section) equipped with hinged doors upstream allowing to funnel the water inside and modify flow properties. Portable flumes have been developed and used to simulate benthic invertebrate drift and sediment transport, but have not been previously been used to examine fish behaviour. Specifically, we tested the predictions that 1) capture probability declined with turbulence, 2) the number of attacks and the proportion of time spent on the substrate decreased with turbulence and 3) parr will preferably selected focal positions with lower turbulence than random locations across the observation section. The portable flume allowed creating four flow treatments on a gradient of mean downstream velocity and turbulence. Fish were fed with brine shrimps and filmed through translucent panels using a submerged camera. Twenty-three juvenile salmon were captured and submitted to each flow treatment for 20 minutes feeding trials. Our results showed high inter-individual variability in the foraging success and time budget within each flow treatment associated to levels of velocity and turbulence. However, the average prey capture probability for the two lower velocity treatments was higher than that for the two higher velocity treatments. An inverse relationship between flow velocity and prey capture probability was observed and might have resulted from a

  7. Field, laboratory and numerical approaches to studying flow through mangrove pneumatophores

    NASA Astrophysics Data System (ADS)

    Chua, V. P.

    2014-12-01

    The circulation of water in riverine mangrove swamps is expected to be influenced by mangrove roots, which in turn affect the nutrients, pollutants and sediments transport in these systems. Field studies were carried out in mangrove areas along the coastline of Singapore where Avicennia marina and Sonneratia alba pneumatophore species are found. Geometrical properties, such as height, diameter and spatial density of the mangrove roots were assessed through the use of photogrammetric methods. Samples of these roots were harvested from mangrove swamps and their material properties, such as bending strength and Young's modulus were determined in the laboratory. It was found that the pneumatophores under hydrodynamic loadings in a mangrove environment could be regarded as fairly rigid. Artificial root models of pneumatophores were fabricated from downscaling based on field observations of mangroves. Flume experiments were performed and measurements of mean flow velocities, Reynolds stress and turbulent kinetic energy were made. The boundary layer formed over the vegetation patch is fully developed after x = 6 m with a linear mean velocity profile. High shear stresses and turbulent kinetic energy were observed at the interface between the top portion of the roots and the upper flow. The experimental data was employed to calibrate and validate three-dimensional simulations of flow in pneumatophores. The simulations were performed with the Delft3D-FLOW model, where the vegetation effect is introduced by adding a depth-distributed resistance force and modifying the k-ɛ turbulence model. The model-predicted profiles for mean velocity, turbulent kinetic energy and concentration were compared with experimental data. The model calibration is performed by adjusting the horizontal and vertical eddy viscosities and diffusivities. A skill assessment of the model is performed using statistical measures that include the Pearson correlation coefficient (r), the mean absolute error

  8. Water Power News | Water Power | NREL

    Science.gov Websites

    the National Renewable Energy Laboratory. February 8, 2018 New Wave Energy Converter Design Inspired new wave energy converter design. January 3, 2018 Student-Designed Flume Arrives at NWTC An NREL collaboration with the Colorado School of Mines stimulated an innovative water flume design. Archives 2018

  9. Rheological properties of simulated debris flows in the laboratory environment

    USGS Publications Warehouse

    Ling, Chi-Hai; Chen, Cheng-lung; Jan, Chyan-Deng; ,

    1990-01-01

    Steady debris flows with or without a snout are simulated in a 'conveyor-belt' flume using dry glass spheres of a uniform size, 5 or 14 mm in diameter, and their rheological properties described quantitatively in constants in a generalized viscoplastic fluid (GVF) model. Close agreement of the measured velocity profiles with the theoretical ones obtained from the GVF model strongly supports the validity of a GVF model based on the continuum-mechanics approach. Further comparisons of the measured and theoretical velocity profiles along with empirical relations among the shear stress, the normal stress, and the shear rate developed from the 'ring-shear' apparatus determine the values of the rheological parameters in the GVF model, namely the flow-behavior index, the consistency index, and the cross-consistency index. Critical issues in the evaluation of such rheological parameters using the conveyor-belt flume and the ring-shear apparatus are thus addressed in this study.

  10. Preferential Flow Paths and Recirculation-Disrupting Jets in the Leeside of Self-Forming Coarse-Grained Laboratory Bedforms

    NASA Astrophysics Data System (ADS)

    Lichtner, D.; Christensen, K. T.; Best, J.; Blois, G.

    2014-12-01

    Exchange of fluid in the near-subsurface of a streambed is influenced by turbulence in the free flow, as well as by bed topography and permeability. Macro-roughness elements such as bedforms are known to produce pressure gradients that drive fluid into the streambed on their stoss sides and out of the bed on their lee sides. To study the modification of the near-bed flow field by self-forming permeable bedforms, laboratory experiments were conducted in a 5 mm wide flume filled with 1.3 mm glass beads. The narrow width of the flume permitted detailed examination of the fluid exiting the bed immediately downstream of a bedform. Dense 2-D velocity field measurements were gathered using particle image velocimetry (PIV). In up to 8% of instantaneous PIV realizations, the flow at the near-bed presented a component perpendicular to the streambed, indicating flow across the interface. At the downstream side of the bedform, such flow disrupted the mean recirculation pattern that is typically observed in finer sediment beds. It is hypothesized that the coarse grain size and the resulting high bed permeability promote such near-surface jet events. A qualitative analysis of raw image frames indicated that an in-place jostling of sediment is associated with these jets thus suggesting that subsurface flow may be characterized by impulsive events. These observations are relevant to hyporheic exchange rates in coarse sediments and can have strong morphodynamic implications as they can explain the lack of ripples and characteristics of dunes in high permeability gravels. Overall, further study of the flow structure over highly permeable streambeds is needed to understand subsurface exchange and bedform initiation.

  11. Laboratory Investigation of Rill Erosion on Compost Blankets under Concentrated Flow Conditions

    EPA Science Inventory

    A flume study was conducted using a soil, yard waste compost, and an erosion control compost to investigate the response to concentrated flow and determine if the shear stress model could be used to describe the response. Yard waste compost (YWC) and the bare Cecil soil (CS) cont...

  12. Flume Experiments on the Influence of Salmon Spawning Density on Grain Stability and Bedload Transport in Gravel-bed Streams

    NASA Astrophysics Data System (ADS)

    Buxton, T. H.

    2015-12-01

    Salmon spawning in streams involves the female salmon digging a pit in the bed where she deposits eggs for fertilization before covering them with gravel excavated from the next pit upstream. Sequences of pit excavation and filling winnow fines, loosen sediment, and move bed material into a tailspill mound resembling the shape of a dune. Research suggests salmonid nests (redds) destabilize streambeds by reducing friction between loosened grains and converging flow that elevates shear stress on redd topography. However, bed stability may be enhanced by form drag from redds in clusters that lower shear stress on the granular bed, but this effect will vary with the proportion of the bed surface that is occupied by redds (P). I used simulated redds and water-worked ("unspawned") beds in a laboratory flume to evaluate these competing influences on grain stability and bedload transport rates with P=0.12, 0.34, and 0.41. Results indicate that competence (largest-grain) and reference transport rate estimates of critical conditions for particle entrainment inversely relate to P. Bedload transport increased as exponential functions of P and excess boundary shear stress. Therefore, redd form drag did not overcome the destabilizing effects of spawning. Instead, grain mobility and bedload transport increased with P because larger areas of the bed were composed of relatively loose, unstable grains and redd topography that experienced elevated shear stress. Consequently, the presence of redds in fish-bearing streams likely reduces the effects of sedimentation from landscape disturbance on stream habitats that salmon use for reproduction.

  13. Large-scale laboratory testing of bedload-monitoring technologies: overview of the StreamLab06 Experiments

    USGS Publications Warehouse

    Marr, Jeffrey D.G.; Gray, John R.; Davis, Broderick E.; Ellis, Chris; Johnson, Sara; Gray, John R.; Laronne, Jonathan B.; Marr, Jeffrey D.G.

    2010-01-01

    A 3-month-long, large-scale flume experiment involving research and testing of selected conventional and surrogate bedload-monitoring technologies was conducted in the Main Channel at the St. Anthony Falls Laboratory under the auspices of the National Center for Earth-surface Dynamics. These experiments, dubbed StreamLab06, involved 25 researchers and volunteers from academia, government, and the private sector. The research channel was equipped with a sediment-recirculation system and a sediment-flux monitoring system that allowed continuous measurement of sediment flux in the flume and provided a data set by which samplers were evaluated. Selected bedload-measurement technologies were tested under a range of flow and sediment-transport conditions. The experiment was conducted in two phases. The bed material in phase I was well-sorted siliceous sand (0.6-1.8 mm median diameter). A gravel mixture (1-32 mm median diameter) composed the bed material in phase II. Four conventional bedload samplers – a standard Helley-Smith, Elwha, BLH-84, and Toutle River II (TR-2) sampler – were manually deployed as part of both experiment phases. Bedload traps were deployed in study Phase II. Two surrogate bedload samplers – stationarymounted down-looking 600 kHz and 1200 kHz acoustic Doppler current profilers – were deployed in experiment phase II. This paper presents an overview of the experiment including the specific data-collection technologies used and the ambient hydraulic, sediment-transport and environmental conditions measured as part of the experiment. All data collected as part of the StreamLab06 experiments are, or will be available to the research community.

  14. Larval habitat choice in still water and flume flows by the opportunistic bivalve Mulinia lateralis

    NASA Astrophysics Data System (ADS)

    Grassle, Judith P.; Snelgrove, Paul V. R.; Butman, Cheryl Ann

    Competent pediveligers of the coot clam Mulinia lateralis (Say) clearly preferred an organically-rich mud over abiotic glass beads in 24-h flume experiments, and often demonstrated the same choice in still-water experiments. We hypothesize that peediveligers with characteristic helical swimming paths above the bottom can exercise habitat choice in both still water nad flow, but that the limited swimming ambits of physiologically older periveligers require near-bottom flows to move the larvae between sediment patches so that they can exercise habitat choice. Although M. lateralis larvae are planktotrophic, their ability to delay metamorphosis in the absence of a preferred sediment cue is limited to about five days, a shorter time than the lecithotrophi larvae of the opportunistic polychaete species, Capitella spp. I and II. Field distributions of all three opportunistic species may result, at least in part, from active habitat selection for high-organic sediments by settling larvae.

  15. Laboratory Governance: Issues for the Study Group on Regional Laboratories.

    ERIC Educational Resources Information Center

    Schultz, Thomas; Dominic, Joseph

    Background information and an analysis of issues involved in the governance of new regional educational laboratories are presented. The new laboratories are to be established through a 1984 competition administered by the National Institute of Education (NIE). The analysis is designed to assist the Study Group on Regional Laboratories to advise…

  16. Hydraulic Physical Model of Debris Flow for Malaysia Case Study

    NASA Astrophysics Data System (ADS)

    Arif Zainol, M. R. R. Mohd; Awahab, M. K.

    2018-06-01

    In the recent decade, several debris flow events occurred and caused hundreds of deaths, missing or injury and damaged many facilities. In addition to causing significant morphological changes along riverbeds and mountain slopes, these flows are frequently reported to bring about extensive property damage and loss of life. Debris flow phenomena occasionally occur in Malaysia and numbers of death reported cause by this event. In order to investigate the debris flow and its deposition process, experiments were conducted at the School of Civil Engineering Laboratory, Universiti Sains Malaysia. The models consists of three main parts which are water tank, rectangular flume and deposition board. A high speed video camera (HSVC) had been placed nearly downstream of the rectangular flume to capture the movement characteristics of particle grain. From this study, the characteristics of particle routing segregation can be understand clearly, therefore this input will be a very useful information to other researchers for further investigation in terms of knowledge sharing between researchers. Catastrophic cause by debris flow event can be minimized therefore in term of economy losses can be reduce and human life can be safe.

  17. Effects of wind waves versus ship waves on tidal marsh plants: a flume study on different life stages of Scirpus maritimus.

    PubMed

    Silinski, Alexandra; Heuner, Maike; Schoelynck, Jonas; Puijalon, Sara; Schröder, Uwe; Fuchs, Elmar; Troch, Peter; Bouma, Tjeerd J; Meire, Patrick; Temmerman, Stijn

    2015-01-01

    Recent research indicates that many ecosystems, including intertidal marshes, follow the alternative stable states theory. This theory implies that thresholds of environmental factors can mark a limit between two opposing stable ecosystem states, e.g. vegetated marshes and bare mudflats. While elevation relative to mean sea level is considered as the overall threshold condition for colonization of mudflats by vegetation, little is known about the individual driving mechanisms, in particular the impact of waves, and more specifically of wave period. We studied the impact of different wave regimes on plants in a full scale flume experiment. Seedlings and adult shoots of the pioneer Scirpus maritimus were subjected to two wave periods at two water levels. Drag forces acting on, and sediment scouring occurring around the plants were quantified, as these are the two main mechanisms determining plant establishment and survival. Depending on life stage, two distinct survival strategies emerge: seedlings present a stress avoidance strategy by being extremely flexible, thus limiting the drag forces and thereby the risk of breaking. Adult shoots present a stress tolerance strategy by having stiffer stems, which gives them a higher resistance to breaking. These strategies work well under natural, short period wind wave conditions. For long period waves, however, caused e.g. by ships, these survival strategies have a high chance to fail as the flexibility of seedlings and stiffness of adults lead to plant tissue failure and extreme drag forces respectively. This results in both cases in strongly bent plant stems, potentially limiting their survival.

  18. Effects of Wind Waves versus Ship Waves on Tidal Marsh Plants: A Flume Study on Different Life Stages of Scirpus maritimus

    PubMed Central

    Schoelynck, Jonas; Puijalon, Sara; Schröder, Uwe; Fuchs, Elmar; Troch, Peter; Bouma, Tjeerd J.; Meire, Patrick; Temmerman, Stijn

    2015-01-01

    Recent research indicates that many ecosystems, including intertidal marshes, follow the alternative stable states theory. This theory implies that thresholds of environmental factors can mark a limit between two opposing stable ecosystem states, e.g. vegetated marshes and bare mudflats. While elevation relative to mean sea level is considered as the overall threshold condition for colonization of mudflats by vegetation, little is known about the individual driving mechanisms, in particular the impact of waves, and more specifically of wave period. We studied the impact of different wave regimes on plants in a full scale flume experiment. Seedlings and adult shoots of the pioneer Scirpus maritimus were subjected to two wave periods at two water levels. Drag forces acting on, and sediment scouring occurring around the plants were quantified, as these are the two main mechanisms determining plant establishment and survival. Depending on life stage, two distinct survival strategies emerge: seedlings present a stress avoidance strategy by being extremely flexible, thus limiting the drag forces and thereby the risk of breaking. Adult shoots present a stress tolerance strategy by having stiffer stems, which gives them a higher resistance to breaking. These strategies work well under natural, short period wind wave conditions. For long period waves, however, caused e.g. by ships, these survival strategies have a high chance to fail as the flexibility of seedlings and stiffness of adults lead to plant tissue failure and extreme drag forces respectively. This results in both cases in strongly bent plant stems, potentially limiting their survival. PMID:25799017

  19. Cross-polarization microwave radar return at severe wind conditions: laboratory model and geophysical model function.

    NASA Astrophysics Data System (ADS)

    Troitskaya, Yuliya; Abramov, Victor; Ermoshkin, Alexey; Zuikova, Emma; Kazakov, Vassily; Sergeev, Daniil; Kandaurov, Alexandr

    2014-05-01

    Satellite remote sensing is one of the main techniques of monitoring severe weather conditions over the ocean. The principal difficulty of the existing algorithms of retrieving wind based on dependence of microwave backscattering cross-section on wind speed (Geophysical Model Function, GMF) is due to its saturation at winds exceeding 25 - 30 m/s. Recently analysis of dual- and quad-polarization C-band radar return measured from satellite Radarsat-2 suggested that the cross-polarized radar return has much higher sensitivity to the wind speed than co-polarized back scattering [1] and conserved sensitivity to wind speed at hurricane conditions [2]. Since complete collocation of these data was not possible and time difference in flight legs and SAR images acquisition was up to 3 hours, these two sets of data were compared in [2] only statistically. The main purpose of this paper is investigation of the functional dependence of cross-polarized radar cross-section on the wind speed in laboratory experiment. Since cross-polarized radar return is formed due to scattering at small-scale structures of the air-sea interface (short-crested waves, foam, sprays, etc), which are well reproduced in laboratory conditions, then the approach based on laboratory experiment on radar scattering of microwaves at the water surface under hurricane wind looks feasible. The experiments were performed in the Wind-wave flume located on top of the Large Thermostratified Tank of the Institute of Applied Physics, where the airflow was produced in the flume with the straight working part of 10 m and operating cross section 0.40?0.40 sq. m, the axis velocity can be varied from 5 to 25 m/s. Microwave measurements were carried out by a coherent Doppler X-band (3.2 cm) scatterometer with the consequent receive of linear polarizations. Experiments confirmed higher sensitivity to the wind speed of the cross-polarized radar return. Simultaneously parameters of the air flow in the turbulent boundary layer

  20. Use of Fiber Bragg Grating (FBG) sensors for performing automated bridge pier structural damage detection and scour monitoring.

    DOT National Transportation Integrated Search

    2012-04-01

    The goal of this study was to evaluate the performance of Fiber Bragg Grating (FBG) sensors able to detect impacts with : different frequencies on a bridge pier. The FBG technology was evaluated under controlled conditions in a laboratory : flume set...

  1. Tsunamis generated by long and thin granular landslides in a large flume

    NASA Astrophysics Data System (ADS)

    Miller, Garrett S.; Andy Take, W.; Mulligan, Ryan P.; McDougall, Scott

    2017-01-01

    In this experimental study, granular material is released down slope to investigate landslide-generated waves. Starting with a known volume and initial position of the landslide source, detailed data are obtained on the velocity and thickness of the granular flow, the shape and location of the submarine landslide deposit, the amplitude and shape of the near-field wave, the far-field wave evolution, and the wave runup elevation on a smooth impermeable slope. The experiments are performed on a 6.7 m long 30° slope on which gravity accelerates the landslides into a 2.1 m wide and 33.0 m long wave flume that terminates with a 27° runup ramp. For a fixed landslide volume of 0.34 m3, tests are conducted in a range of still water depths from 0.05 to 0.50 m. Observations from high-speed cameras and measurements from wave probes indicate that the granular landslide moves as a long and thin train of material, and that only a portion of the landslide (termed the "effective mass") is engaged in activating the leading wave. The wave behavior is highly dependent on the water depth relative to the size of the landslide. In deeper water, the near-field wave behaves as a stable solitary-like wave, while in shallower water, the wave behaves as a breaking dissipative bore. Overall, the physical model observations are in good agreement with the results of existing empirical equations when the effective mass is used to predict the maximum near-field wave amplitude, the far-field amplitude, and the runup of tsunamis generated by granular landslides.

  2. A comparison of two infiltration models applied to simulation of overland flow over a two-dimensional flume.

    PubMed

    Mallari, K J B; Kim, H; Pak, G; Aksoy, H; Yoon, J

    2015-01-01

    At the hillslope scale, where the rill-interrill configuration plays a significant role, infiltration is one of the major hydrologic processes affecting the generation of overland flow. As such, it is important to achieve a good understanding and accurate modelling of this process. Horton's infiltration has been widely used in many hydrologic models, though it has been occasionally found limited in handling adequately the antecedent moisture conditions (AMC) of soil. Holtan's model, conversely, is thought to be able to provide better estimation of infiltration rates as it can directly account for initial soil water content in its formulation. In this study, the Holtan model is coupled to an existing overland flow model, originally using Horton's model to account for infiltration, in an attempt to improve the prediction of runoff. For calibration and validation, experimental data from a two-dimensional flume which is incorporated with hillslope configuration have been used. Calibration and validation results showed that Holtan's model was able to improve the modelling results with better performance statistics than the Horton-coupled model. Holtan's infiltration equation, which allows accounting for AMC, provided an advantage and resulted in better runoff prediction of the model.

  3. Effect of sediment transport boundary conditions on the numerical modeling of bed morphodynamics

    USDA-ARS?s Scientific Manuscript database

    Experimental sediment transport studies in laboratory flumes can use two sediment-supply methods: an imposed feed at the upstream end or recirculation of sediment from the downstream end to the upstream end. These methods generally produce similar equilibrium bed morphology, but temporal evolution c...

  4. The role of varying flow on channel morphology: a flume experiment

    NASA Astrophysics Data System (ADS)

    Hempel, L. A.; Grant, G.; Eaton, B. C.; Hassan, M. A.; Lewis, S.

    2017-12-01

    Numerous studies have explored how alluvial channels develop under different sediment and flow conditions, yet we still know very little about how channels adjust and respond to changing flow conditions. One reason for this oversight is the long-held idea that channels with complex flow regimes are adjusted to a single, channel-forming discharge. But growing evidence shows that channel form reflects time-dependent processes occuring over multiple flows. To better understand how stream channels adjust to a range of flows, and identify the timescales associated with those adjustments, we conducted a series of hydrograph experiments in a freely-adjustable flume that developed a self-formed, meander pattern with pool-riffle morphology. Hydrographs had different shapes, magnitudes, and durations, but the total sediment volume fed under equilibrium conditions was kept constant among experiments. We found that hydrograph shape controlled channel morphology, the rate of channel development, and degree of regularity in the pool-riffle pattern. Hydrographs with slowly rising rates of rise and fall produced channels that were equivalent in size to channels generated from constant flow experiments, and had regularly spaced pool-riffle and meander patterns, while hydrographs with fast rates of rise and fall produced undersized channels with a chaotic bed structure and pool-riffle pattern. The latter suggests that during quickly rising hydrographs, the flow rate increases faster than the channel capacity and planform pattern adjusts. We confirmed these observations by comparing the timescales associated with pool-riffle and planform curvature development, which were identified under simple, constant flow conditions, to the total duration of the hydrograph. Hydrographs with step durations equal to or longer than the channel adjustment time produced channels with a more regular pool-riffle patterns compared to channels with step durations shorter than the adjustment time. This

  5. Field flume reveals aquatic vegetation's role in sediment and particulate phosphorus transport in a shallow aquatic ecosystem

    USGS Publications Warehouse

    Harvey, J.W.; Noe, G.B.; Larsen, L.G.; Nowacki, D.J.; McPhillips, L.E.

    2011-01-01

    Flow interactions with aquatic vegetation and effects on sediment transport and nutrient redistribution are uncertain in shallow aquatic ecosystems. Here we quantified sediment transport in the Everglades by progressively increasing flow velocity in a field flume constructed around undisturbed bed sediment and emergent macrophytes. Suspended sediment 100 μm became dominant at higher velocity steps after a threshold shear stress for bed floc entrainment was exceeded. Shedding of vortices that had formed downstream of plant stems also occurred on that velocity step which promoted additional sediment detachment from epiphyton. Modeling determined that the potentially entrainable sediment reservoir, 46 g m−2, was similar to the reservoir of epiphyton (66 g m−2) but smaller than the reservoir of flocculent bed sediment (330 g m−2). All suspended sediment was enriched in phosphorus (by approximately twenty times) compared with bulk sediment on the bed surface and on plant stems, indicating that the most easily entrainable sediment is also the most nutrient rich (and likely the most biologically active).

  6. The effect of coarse gravel on cohesive sediment entrapment in an annular flume

    NASA Astrophysics Data System (ADS)

    Glasbergen, K.; Stone, M.; Krishnappan, B.; Dixon, J.; Silins, U.

    2015-03-01

    While cohesive sediment generally represents a small fraction (<0.5%) of the total sediment mass stored in gravel-bed rivers, it can strongly influence physical and biogeochemical processes in the hyporheic zone and alter aquatic habitat. This research was conducted to examine mechanisms governing the interaction of cohesive sediments with gravel beds in the Elbow River, Alberta, Canada. A series of erosion and deposition experiments with and without a gravel bed were conducted in a 5-m diameter annular flume. The critical shear stress for deposition and erosion of cohesive sediment without gravel was 0.115 Pa and 0.212 Pa, respectively. In experiments with a gravel bed, cohesive sediment moved from the water column into the gravel bed via the coupling of surface and pore water flow. Once in the gravel bed, cohesive sediments were not mobilized under the maximum applied shear stresses (1.11 Pa) used in the experiment. The gravel bed had an entrapment coefficient (ratio between the entrapment flux and the settling flux) of 0.2. Accordingly, when flow conditions are sufficient to produce a shear stress that will mobilize the armour layer of the gravel bed (>16 Pa), cohesive materials trapped within the gravel bed will be entrained and transported into the Glenmore Reservoir, where sediment-associated nutrients may pose treatment challenges to the drinking water supply.

  7. Clinical Laboratory Automation: A Case Study

    PubMed Central

    Archetti, Claudia; Montanelli, Alessandro; Finazzi, Dario; Caimi, Luigi; Garrafa, Emirena

    2017-01-01

    Background This paper presents a case study of an automated clinical laboratory in a large urban academic teaching hospital in the North of Italy, the Spedali Civili in Brescia, where four laboratories were merged in a unique laboratory through the introduction of laboratory automation. Materials and Methods The analysis compares the preautomation situation and the new setting from a cost perspective, by considering direct and indirect costs. It also presents an analysis of the turnaround time (TAT). The study considers equipment, staff and indirect costs. Results The introduction of automation led to a slight increase in equipment costs which is highly compensated by a remarkable decrease in staff costs. Consequently, total costs decreased by 12.55%. The analysis of the TAT shows an improvement of nonemergency exams while emergency exams are still validated within the maximum time imposed by the hospital. Conclusions The strategy adopted by the management, which was based on re-using the available equipment and staff when merging the pre-existing laboratories, has reached its goal: introducing automation while minimizing the costs. Significance for public health Automation is an emerging trend in modern clinical laboratories with a positive impact on service level to patients and on staff safety as shown by different studies. In fact, it allows process standardization which, in turn, decreases the frequency of outliers and errors. In addition, it induces faster processing times, thus improving the service level. On the other side, automation decreases the staff exposition to accidents strongly improving staff safety. In this study, we analyse a further potential benefit of automation, that is economic convenience. We study the case of the automated laboratory of one of the biggest hospital in Italy and compare the cost related to the pre and post automation situation. Introducing automation lead to a cost decrease without affecting the service level to patients

  8. Using the raindrop size distribution to quantify the soil detachment rate at the laboratory scale

    NASA Astrophysics Data System (ADS)

    Jomaa, S.; Jaffrain, J.; Barry, D. A.; Berne, A.; Sander, G. C.

    2010-05-01

    Rainfall simulators are beneficial tools for studying soil erosion processes and sediment transport for different circumstances and scales. They are useful to better understand soil erosion mechanisms and, therefore, to develop and validate process-based erosion models. Simulators permit experimental replicates for both simple and complex configurations. The 2 m × 6 m EPFL erosion flume is equipped with a hydraulic slope control and a sprinkling system located on oscillating bars 3 m above the surface. It provides a near-uniform spatial rainfall distribution. The intensity of the precipitation can be adjusted by changing the oscillation interval. The flume is filled to a depth of 0.32 m with an agricultural loamy soil. Raindrop detachment is an important process in interrill erosion, the latter varying with the soil properties as well as the raindrop size distribution and drop velocity. Since the soil detachment varies with the kinetic energy of raindrops, an accurate characterization of drop size distribution (DSD, measured, e.g., using a laser disdrometer) can potentially support erosion calculations. Here, a laser disdrometer was used at different rainfall intensities in the EPFL flume to quantify the rainfall event in terms of number of drops, diameter and velocity. At the same time, soil particle motion was measured locally using splash cups. These cups measured the detached material rates into upslope and downslope compartments. In contrast to previously reported splash cup experiments, the cups used in this study were equipped at the top with upside-down funnels, the upper part having the same diameter as the soil sampled at the bottom. This ensured that the soil detached and captured by the device was not re-exposed to rainfall. The experimental data were used to quantify the relationship between the raindrop distribution and the splash-driven sediment transport.

  9. Clinical Laboratory Automation: A Case Study.

    PubMed

    Archetti, Claudia; Montanelli, Alessandro; Finazzi, Dario; Caimi, Luigi; Garrafa, Emirena

    2017-04-13

    This paper presents a case study of an automated clinical laboratory in a large urban academic teaching hospital in the North of Italy, the Spedali Civili in Brescia, where four laboratories were merged in a unique laboratory through the introduction of laboratory automation. The analysis compares the preautomation situation and the new setting from a cost perspective, by considering direct and indirect costs. It also presents an analysis of the turnaround time (TAT). The study considers equipment, staff and indirect costs. The introduction of automation led to a slight increase in equipment costs which is highly compensated by a remarkable decrease in staff costs. Consequently, total costs decreased by 12.55%. The analysis of the TAT shows an improvement of nonemergency exams while emergency exams are still validated within the maximum time imposed by the hospital. The strategy adopted by the management, which was based on re-using the available equipment and staff when merging the pre-existing laboratories, has reached its goal: introducing automation while minimizing the costs.

  10. Zero-gravity cloud physics laboratory: Experiment program definition and preliminary laboratory concept studies

    NASA Technical Reports Server (NTRS)

    Eaton, L. R.; Greco, E. V.

    1973-01-01

    The experiment program definition and preliminary laboratory concept studies on the zero G cloud physics laboratory are reported. This program involves the definition and development of an atmospheric cloud physics laboratory and the selection and delineations of a set of candidate experiments that must utilize the unique environment of zero gravity or near zero gravity.

  11. First laboratory insight on the behavioral rhythms of the bathyal crab Geryon longipes

    NASA Astrophysics Data System (ADS)

    Nuñez, J. D.; Sbragaglia, V.; García, J. A.; Company, J. B.; Aguzzi, J.

    2016-10-01

    The deep sea is the largest and at the same time least explored biome on Earth, but quantitative studies on the behavior of bathyal organisms are scarce because of the intrinsic difficulties related to in situ observations and maintaining animals in aquaria. In this study, we reported, for the first time, laboratory observations on locomotor rhythms and other behavioral observations (i.e. feeding, exploring and self-grooming) for the bathyal crab Geryon longipes. Crabs were collected on the middle-lower slope (720-1750 m) off the coast of Blanes (Spain). Inertial (18 h) water currents and monochromatic blue (i.e. 470 nm) light-darkness (24 h) cycles were simulated in two different experiments in flume tanks endowed with burrows. Both cycles were simulated in order to investigate activity rhythms regulation in Mediterranean deep-sea benthos. Crabs showed rhythmic locomotor activity synchronized to both water currents and light-darkness cycles. In general terms, feeding and exploring behaviors also followed the same pattern. Results presented here indicate the importance of local inertial (18 h) periodicity of water currents at the seabed as a temporal cue regulating the behavior of bathyal benthic fauna in all continental margin areas where the effects of tides is negligible.

  12. Depletion and biodegradation of hydrocarbons in dispersions and emulsions of the Macondo 252 oil generated in an oil-on-seawater mesocosm flume basin.

    PubMed

    Brakstad, Odd G; Daling, Per S; Faksness, Liv-G; Almås, Inger K; Vang, Siv-H; Syslak, Line; Leirvik, Frode

    2014-07-15

    Physically and chemically (Corexit 9500) generated Macondo 252 oil dispersions, or emulsions (no Corexit), were prepared in an oil-on-seawater mesocosm flume basin at 30-32 °C, and studies of oil compound depletion performed for up to 15 days. The use of Corexit 9500 resulted in smaller median droplet size than in a physically generated dispersion. Rapid evaporation of low boiling point oil compounds (C⩽15) appeared in all the experiments. Biodegradation appeared to be an important depletion process for compounds with higher boiling points in the dispersions, but was negligible in the surface emulsions. While n-alkane biodegradation was faster in chemically than in physically dispersed oil no such differences were determined for 3- and 4-ring PAH compounds. In the oil dispersions prepared by Corexit 9500, increased cell concentrations, reduction in bacterial diversity, and a temporary abundance of bacteria containing an alkB gene were associated with oil biodegradation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Tethered gravity laboratories study

    NASA Technical Reports Server (NTRS)

    Lucchetti, F.

    1989-01-01

    Variable Gravity Laboratory studies are discussed. The following subject areas are covered: (1) conceptual design and engineering analysis; (2) control strategies (fast crawling maneuvers, main perturbations and their effect upon the acceleration level); and (3) technology requirements.

  14. Large wood transport and jam formation in a series of flume experiments

    NASA Astrophysics Data System (ADS)

    Davidson, S. L.; MacKenzie, L. G.; Eaton, B. C.

    2015-12-01

    Large wood has historically been removed from streams, resulting in the depletion of in-stream wood in waterways worldwide. As wood increases morphological and hydraulic complexity, the addition of large wood is commonly employed as a means to rehabilitate in-stream habitat. At present, however, the scientific understanding of wood mobilization and transport is incomplete. This paper presents results from a series of four flume experiments in which wood was added to a reach to investigate the piece and reach characteristics that determine wood stability and transport, as well as the time scale required for newly recruited wood to self-organize into stable jams. Our results show that wood transitions from a randomly distributed newly recruited state to a self-organized, or jam-stabilized state, over the course of a single bankfull flow event. Statistical analyses of piece mobility during this transitional period indicate that piece irregularities, especially rootwads, dictate the stability of individual wood pieces; rootwad presence or absence accounts for up to 80% of the variance explained by linear regression models for transport distance. Furthermore, small pieces containing rootwads are especially stable. Large ramped pieces provide nuclei for the formation of persistent wood jams, and the frequency of these pieces in the reach impacts the travel distance of mobile wood. This research shows that the simulation of realistic wood dynamics is possible using a simplified physical model, and also has management implications, as it suggests that randomly added wood may organize into persistent, stable jams, and characterizes the time scale for this transition.

  15. Bed forms created by simulated waves and currents in a large flume

    USGS Publications Warehouse

    Lacy, Jessica R.; Rubin, David M.; Ikeda, Hiroshi; Mokudai, Kuniyasu; Hanes, Daniel M.

    2007-01-01

    The morphology and evolution of bed forms created by combinations of waves and currents were investigated using an oscillating plate in a 4-m-wide flume. Current speed ranged from 0 to 30 cm/s, maximum oscillatory velocity ranged from 20 to 48 cm/s, oscillation period was 8 s (except for one run with 12 s period), and the median grain size was 0.27 mm. The angle between oscillations and current was 90°, 60°, or 45°. At the end of each run the sand bed was photographed and ripple dimensions were measured. Ripple wavelength was also determined from sonar images collected throughout the runs. Increasing the ratio of current to wave (i.e., oscillatory) velocity decreased ripple height and wavelength, in part because of the increased fluid excursion during the wave period. Increasing the ratio of current to waves, or decreasing the angle between current and waves, increased the three-dimensionality of bed forms. During the runs, ripple wavelength increased by a factor of about 2. The average number of wave periods for evolution of ripple wavelength to 90% of its final value was 184 for two-dimensional ripples starting from a flat bed. Bed form orientations at the end of each run were compared to four potential controlling factors: the directions of waves, current, maximum instantaneous bed shear stress, and maximum gross bed form normal transport (MGBNT). The directions of waves and of MGBNT were equally good predictors of bed form orientations, and were significantly better than the other two factors.

  16. Local sediment scour model tests for the Woodrow Wilson Bridge piers

    USGS Publications Warehouse

    Sheppard, D.M.; Jones, J.S.; Odeh, M.; Glasser, T.

    2004-01-01

    The Woodrow Wilson Bridge on I-495 over the Potomac River in Prince Georges County, Maryland is being replaced. Physical local scour model studies for the proposed piers for the new bridge were performed in order to help establish design scour depths. Tests were conducted in two different flumes, one in the USGS-BRD Conte Research Center in Turners Falls, Massachusetts and one in the FHWA Turner Fairbanks Laboratory in McLean, Virginia. Due to space limitations in this publication only the tests conducted in the USGS flume are presented in this paper. Two different pier designs were tested. One of the piers was also tested with two different diameter dolphin systems. Copyright ASCE 2004.

  17. Laboratory Plasma Studies

    DTIC Science & Technology

    1989-05-23

    Intense Rela- tivistic Electron Beams S . A Compact Accelerator Powercd by the Relativistic Klystron Amplifier T. Numerical and Experimental Studies of...Research Laboratory Washingto, IX 2075.6000 NRL Memorandum Report 6419 Megavolt, Multi-Kiloamp K - Band Gyrotron Oscillator Experiment W. M. BLACK,* S . H...Ka- Band Gyrotron Oscillator Experiments with Slotted and Unslotted Cavities S . H. GOLD, MEMBER, IEEE. A. W. FLIFLET, MEMBER, IEEE, W. M. MANHEIMER

  18. Instrumentation for a dry-pond detention study

    USGS Publications Warehouse

    Pope, L.M.; Jennings, M.E.; Thibodeaux, K.G.

    1988-01-01

    A 12.3-acre, fully urbanized, residential land-use catchment was instrumented by the U. S. Geological Survey in Topeka, Kansas. Hydraulic instrumentation for flow measurement includes two types of flumes, a pipe-insert flume and a culvert-inlet (manhole) flume. Samples of rainfall and runoff for water-quality analyses were collected by automatic, 3-liter, 24-sample capacity water samples controlled by multichannel data loggers. Ancillary equipment included a raingage and wet/dry atmospheric-deposition sampler. Nineteen stormwater runoff events were monitored at the site using the instrumentation system. The system has a high reliability of data capture and permits an accurate determination of storm-water loads.

  19. The effect of bedload transport rates on bedform and planform morphological development in a laboratory meandering stream under varying flow conditions

    NASA Astrophysics Data System (ADS)

    Sullivan, C.; Good, R. G. R.; Binns, A. D.

    2017-12-01

    Sediment transport processes in streams provides valuable insight into the temporal evolution of planform and bedform geometry. The majority of previous experimental research in the literature has focused on bedload transport and corresponding bedform development in rectangular, confined channels, which does not consider planform adjustment processes in streams. In contrast, research conducted with laboratory streams having movable banks can investigate planform development in addition to bedform development, which is more representative of natural streams. The goal of this research is to explore the relationship between bedload transport rates and the morphological adjustments in meandering streams. To accomplish this, a series of experimental runs were conducted in a 5.6 m by 1.9 m river basin flume at the University of Guelph to analyze the bedload impacts on bed formations and planform adjustments in response to varying flow conditions. In total, three experimental runs were conducted: two runs using steady state conditions and one run using unsteady flow conditions in the form of a symmetrical hydrograph implementing quasi steady state flow. The runs were performed in a series of time-steps in order to monitor the evolution of the stream morphology and the bedload transport rates. Structure from motion (SfM) was utilized to capture the channel morphology after each time-step, and Agisoft PhotoScan software was used to produce digital elevation models to analyze the morphological evolution of the channel with time. Bedload transport rates were quantified using a sediment catch at the end of the flume. Although total flow volumes were similar for each run, the morphological evolution and bedload transport rates in each run varied. The observed bedload transport rates from the flume are compared with existing bedload transport formulas to assess their accuracy with respect to sediment transport in unconfined meandering channels. The measured sediment transport

  20. Field swimming performance of bluegill sunfish, Lepomis macrochirus: implications for field activity cost estimates and laboratory measures of swimming performance.

    PubMed

    Cathcart, Kelsey; Shin, Seo Yim; Milton, Joanna; Ellerby, David

    2017-10-01

    Mobility is essential to the fitness of many animals, and the costs of locomotion can dominate daily energy budgets. Locomotor costs are determined by the physiological demands of sustaining mechanical performance, yet performance is poorly understood for most animals in the field, particularly aquatic organisms. We have used 3-D underwater videography to quantify the swimming trajectories and propulsive modes of bluegills sunfish ( Lepomis macrochirus , Rafinesque) in the field with high spatial (1-3 mm per pixel) and temporal (60 Hz frame rate) resolution. Although field swimming trajectories were variable and nonlinear in comparison to quasi steady-state swimming in recirculating flumes, they were much less unsteady than the volitional swimming behaviors that underlie existing predictive models of field swimming cost. Performance analyses suggested that speed and path curvature data could be used to derive reasonable estimates of locomotor cost that fit within measured capacities for sustainable activity. The distinct differences between field swimming behavior and performance measures obtained under steady-state laboratory conditions suggest that field observations are essential for informing approaches to quantifying locomotor performance in the laboratory.

  1. Experimental tsunami deposits: Linking hydrodynamics to sediment entrainment, advection lengths and downstream fining

    NASA Astrophysics Data System (ADS)

    Johnson, Joel P. L.; Delbecq, Katie; Kim, Wonsuck; Mohrig, David

    2016-01-01

    A goal of paleotsunami research is to quantitatively reconstruct wave hydraulics from sediment deposits in order to better understand coastal hazards. Simple models have been proposed to predict wave heights and velocities, based largely on deposit grain size distributions (GSDs). Although seemingly consistent with some recent tsunamis, little independent data exist to test these equations. We conducted laboratory experiments to evaluate inversion assumptions and uncertainties. A computer-controlled lift gate instantaneously released 6.5 m3 of water into a 32 m flume with shallow ponded water, creating a hydraulic bore that transported sand from an upstream source dune. Differences in initial GSDs and ponded water depths influenced entrainment, transport, and deposition. While the source dune sand was fully suspendable based on size alone, experimental tsunamis produced deposits dominated by bed load sand transport in the upstream 1/3 of the flume and suspension-dominated transport downstream. The suspension deposits exhibited downstream fining and thinning. At 95% confidence, a published advection-settling model predicts time-averaged flow depths to approximately a factor of two, and time-averaged downstream flow velocities to within a factor of 1.5. Finally, reasonable scaling is found between flume and field cases by comparing flow depths, inundation distances, Froude numbers, Rouse numbers and grain size trends in suspension-dominated tsunami deposits, justifying laboratory study of sediment transport and deposition by tsunamis.

  2. High speed video shooting with continuous-wave laser illumination in laboratory modeling of wind - wave interaction

    NASA Astrophysics Data System (ADS)

    Kandaurov, Alexander; Troitskaya, Yuliya; Caulliez, Guillemette; Sergeev, Daniil; Vdovin, Maxim

    2014-05-01

    measured air velocity fluctuations. This data was then compared to values retrieved from wind speed profiles [2]. Visualization of water surface structure and droplets under strong wind conditions was carried out at the Wind - wave stratified flume of IAP RAS with high-speed camera NAC Memrecam HX-3 having a record-breaking performance at the moment. Shooting was performed at frame rates over 4500 Hz in 1080p resolution (1920 x 1080 px). Experimental study of droplets under strong winds has discovered a "bag breakup" droplet-production mechanism (observed previously in technical devices for liquid disintegration [3]). The investigation on this mechanism in the laboratory can improve the parameterization of heat fluxes in the models of hurricanes and intense sea storms. This work was supported by RFBR grants (project code 13-05-00865, 13-05-12093, 12-05-01064, 14-08-31740, 14-05-31415), President Grant for young scientists MK-3550.2014.5 and grant of the Government of the Russian Federation designed to support scientific research project implemented under the supervision of leading scientists at Russian institutions of higher learning (project code 11.G34.31.0048). References 1. Troitskaya Yu., D. Sergeev, O. Ermakova, G. Balandina (2011), Statistical Parameters of the Air Turbulent Boundary Layer over Steep Water Waves Measured by the PIV Technique, J. Phys. Oceanogr., 41, 1421-1454 2. Troitskaya, Y. I., D. A. Sergeev, A. A. Kandaurov, G. A. Baidakov, M. A. Vdovin, and V. I. Kazakov "Laboratory and theoretical modeling of air-sea momentum transfer under severe wind conditions" J. Geophys. Res., 117, C00J21, 2012. 3. Villermaux, E. (2007), Fragmentation, Ann. Review Fluid Mech., 39,419-446, doi:10.1146/annurev.fluid.39.050905.110214.

  3. Variety of Sedimentary Process and Distribution of Tsunami Deposits in Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Yamaguchi, N.; Sekiguchi, T.

    2017-12-01

    As an indicator of the history and magnitude of paleotsunami events, tsunami deposits have received considerable attention. To improve the identification and interpretation of paleotsunami deposits, an understanding of sedimentary process and distribution of tsunami deposits is crucial. Recent detailed surveys of onshore tsunami deposits including the 2004 Indian Ocean tsunami and the 2011 Tohoku-oki tsunami have revealed that terrestrial topography causes a variety of their features and distributions. Therefore, a better understanding of possible sedimentary process and distribution on such influential topographies is required. Flume experiments, in which sedimentary conditions can be easily controlled, can provide insights into the effects of terrestrial topography as well as tsunami magnitude on the feature of tsunami deposits. In this presentation, we report laboratory experiments that focused on terrestrial topography including a water body (e.g. coastal lake) on a coastal lowland and a cliff. In both cases, the results suggested relationship between the distribution of tsunami deposits and the hydraulic condition of the tsunami flow associated with the terrestrial topography. These experiments suggest that influential topography would enhance the variability in thickness of tsunami deposits, and thus, in reconstructions of paleotsunami events using sedimentary records, we should take into account such anomalous distribution of tsunami deposits. Further examination of the temporal sequence of sedimentary process in laboratory tsunamis may improve interpretation and estimation of paleotsunami events.

  4. Deformed barchans under alternating flows: Flume experiments and comparison with barchan dunes within Proctor Crater, Mars

    NASA Astrophysics Data System (ADS)

    Taniguchi, Keisuke; Endo, Noritaka

    2007-10-01

    It is generally considered that barchans, isolated crescentic-shaped dunes, develop where wind is unidirectional and the available sand is insufficient to cover the entire dune field; however, Bishop [Bishop, M.A., 2001. Seasonal variation of crescentic dune morphology and morphometry, Strzelecki Simpson desert, Australia. Earth Surface Process and Landforms 26, 783 791.] observed barchans that developed in areas where winds blow seasonally in opposite directions and described a peculiar deformation feature, the “rear slipface,” that is not found in ordinary barchans. Barchans under such bidirectional flows are poorly understood, and it is necessary to study barchans that formed under many different flow conditions. We conducted flume experiments to investigate the deformation of barchans under alternating water flow, and observed new deformation features in addition to rear slipfaces. We conclude that the deformation of barchans can be categorized into four types, one of which shows morphologies similar to barchans within Proctor Crater, Mars. The deformation type depends on the strength of the reverse flow relative to the forward flow and the absolute velocity of the forward flow. Comparison of our results with barchan dunes within Proctor Crater enable us to qualitatively estimate the wind strength and direction related to dune formation on Mars. These results are in agreement with those of Fenton et al. [Fenton, L.K., Toigo, A.D., Richardson, M.I., 2005. Aeolian processes in Proctor Crater on Mars: Mesoscale modeling of dune-forming winds. Journal of Geophysical Research 110 (E6), E06005.].

  5. Hydrologic control on the root growth of Salix cuttings at the laboratory scale

    NASA Astrophysics Data System (ADS)

    Bau', Valentina; Calliari, Baptiste; Perona, Paolo

    2017-04-01

    Riparian plant roots contribute to the ecosystem functioning and, to a certain extent, also directly affect fluvial morphodynamics, e.g. by influencing sediment transport via mechanical stabilization and trapping. There is much both scientific and engineering interest in understanding the complex interactions among riparian vegetation and river processes. For example, to investigate plant resilience to uprooting by flow, one should quantify the probability that riparian plants may be uprooted during specific flooding event. Laboratory flume experiments are of some help to this regard, but are often limited to use grass (e.g., Avena and Medicago sativa) as vegetation replicate with a number of limitations due to fundamental scaling problems. Hence, the use of small-scale real plants grown undisturbed in the actual sediment and within a reasonable time frame would be particularly helpful to obtain more realistic flume experiments. The aim of this work is to develop and tune an experimental technique to control the growth of the root vertical density distribution of small-scale Salix cuttings of different sizes and lengths. This is obtained by controlling the position of the saturated water table in the sedimentary bed according to the sediment size distribution and the cutting length. Measurements in the rhizosphere are performed by scanning and analysing the whole below-ground biomass by means of the root analysis software WinRhizo, from which root morphology statistics and the empirical vertical density distribution are obtained. The model of Tron et al. (2015) for the vertical density distribution of the below-ground biomass is used to show that experimental conditions that allow to develop the desired root density distribution can be fairly well predicted. This augments enormously the flexibility and the applicability of the proposed methodology in view of using such plants for novel flow erosion experiments. Tron, S., Perona, P., Gorla, L., Schwarz, M., Laio, F

  6. MINErosion 3: Using measurements on a tilting flume-rainfall simulator facility to predict erosion rates from post-mining landscapes in Central Queensland, Australia

    PubMed Central

    Khalifa, Ashraf M.; Yu, Bofu; Caroll, Chris; Burger, Peter; Mulligan, David

    2018-01-01

    Open-cut coal mining in Queensland results in the formation of extensive saline overburden spoil-piles with steep slopes at the angle of repose (approximately 75% or 37o). These spoil-piles are generally found in multiple rows, several kilometers in length and heights of up to 50 or 60 m above the original landscape. They are highly dispersive and erodible. Legislation demands that these spoil piles be rehabilitated to minimize on-site and off-site discharges of sediment and salt into the surrounding environment. To achieve this, the steep slopes must be reduced, stabilized against erosion, covered with topsoil and re-vegetated. Key design criteria (slope gradient, slope length and vegetation cover) are required for the construction of post-mining landscapes that will result in acceptable erosion rates. A novel user-friendly hillslope computer model MINErosion 3.4 was developed that can accurately predict potential erosion rates from field scale hillslopes using parameters measured with a 3m laboratory tilting flume-rainfall simulator or using routinely measured soil physical and chemical properties. This model links MINErosion 2 with a novel consolidation and above ground vegetation cover factors, to the RUSLE and MUSLE equations to predict the mean annual and storm event erosion rates. The RUSLE-based prediction of the mean annual erosion rates allow minesites to derive the key design criteria of slope length, slope gradient and vegetation cover that would lead to acceptable erosion rates. The MUSLE-based prediction of storm event erosion rates will be useful as input into risk analysis of potential damage from erosion. MINErosion 3.4 was validated against erosion measured on 20 m field erosion plots established on post-mining landscapes at the Oakey Creek and Curragh coalmines, as well as on 120 and 70 m erosion plots on postmining landscapes at Kidston Gold Mine. PMID:29590190

  7. MINErosion 3: Using measurements on a tilting flume-rainfall simulator facility to predict erosion rates from post-mining landscapes in Central Queensland, Australia.

    PubMed

    So, Hwat Bing; Khalifa, Ashraf M; Yu, Bofu; Caroll, Chris; Burger, Peter; Mulligan, David

    2018-01-01

    Open-cut coal mining in Queensland results in the formation of extensive saline overburden spoil-piles with steep slopes at the angle of repose (approximately 75% or 37o). These spoil-piles are generally found in multiple rows, several kilometers in length and heights of up to 50 or 60 m above the original landscape. They are highly dispersive and erodible. Legislation demands that these spoil piles be rehabilitated to minimize on-site and off-site discharges of sediment and salt into the surrounding environment. To achieve this, the steep slopes must be reduced, stabilized against erosion, covered with topsoil and re-vegetated. Key design criteria (slope gradient, slope length and vegetation cover) are required for the construction of post-mining landscapes that will result in acceptable erosion rates. A novel user-friendly hillslope computer model MINErosion 3.4 was developed that can accurately predict potential erosion rates from field scale hillslopes using parameters measured with a 3m laboratory tilting flume-rainfall simulator or using routinely measured soil physical and chemical properties. This model links MINErosion 2 with a novel consolidation and above ground vegetation cover factors, to the RUSLE and MUSLE equations to predict the mean annual and storm event erosion rates. The RUSLE-based prediction of the mean annual erosion rates allow minesites to derive the key design criteria of slope length, slope gradient and vegetation cover that would lead to acceptable erosion rates. The MUSLE-based prediction of storm event erosion rates will be useful as input into risk analysis of potential damage from erosion. MINErosion 3.4 was validated against erosion measured on 20 m field erosion plots established on post-mining landscapes at the Oakey Creek and Curragh coalmines, as well as on 120 and 70 m erosion plots on postmining landscapes at Kidston Gold Mine.

  8. Tethered gravity laboratories study

    NASA Technical Reports Server (NTRS)

    Lucchetti, F.

    1990-01-01

    The scope of the study is to investigate ways of controlling the microgravity environment of the International Space Station by means of a tethered system. Four main study tasks were performed. First, researchers analyzed the utilization of the tether systems to improve the lowest possible steady gravity level on the Space Station and the tether capability to actively control the center of gravity position in order to compensate for activities that would upset the mass distribution of the Station. The purpose of the second task was to evaluate the whole of the experiments performable in a variable gravity environment and the related beneficial residual accelerations, both for pure and applied research in the fields of fluid, materials, and life science, so as to assess the relevance of a variable g-level laboratory. The third task involves the Tethered Variable Gravity Laboratory. The use of the facility that would crawl along a deployed tether and expose experiments to varying intensities of reduced gravity is discussed. Last, a study performed on the Attitude Tether Stabilizer concept is discussed. The stabilization effect of ballast masses tethered to the Space Station was investigated as a means of assisting the attitude control system of the Station.

  9. Human Laboratory Studies on Cannabinoids and Psychosis.

    PubMed

    Sherif, Mohamed; Radhakrishnan, Rajiv; D'Souza, Deepak Cyril; Ranganathan, Mohini

    2016-04-01

    Some of the most compelling evidence supporting an association between cannabinoid agonists and psychosis comes from controlled laboratory studies in humans. Randomized, double-blind, placebo-controlled, crossover laboratory studies demonstrate that cannabinoid agonists, including phytocannabinoids and synthetic cannabinoids, produce a wide range of positive, negative, and cognitive symptoms and psychophysiologic deficits in healthy human subjects that resemble the phenomenology of schizophrenia. These effects are time locked to drug administration, are dose related, and are transient and rarely necessitate intervention. The magnitude of effects is similar to the effects of ketamine but qualitatively distinct from other psychotomimetic drugs, including ketamine, amphetamine, and salvinorin A. Cannabinoid agonists have also been shown to transiently exacerbate symptoms in individuals with schizophrenia in laboratory studies. Patients with schizophrenia are more vulnerable than healthy control subjects to the acute behavioral and cognitive effects of cannabinoid agonists and experience transient exacerbation of symptoms despite treatment with antipsychotic medications. Furthermore, laboratory studies have failed to demonstrate any "beneficial" effects of cannabinoid agonists in individuals with schizophrenia-challenging the cannabis self-medication hypothesis. Emerging evidence suggests that polymorphisms of several genes related to dopamine metabolism (e.g., COMT, DAT1, and AKT1) may moderate the effects of cannabinoid agonists in laboratory studies. Cannabinoid agonists induce dopamine release, although the magnitude of release does not appear to be commensurate to the magnitude and spectrum of their acute psychotomimetic effects. Interactions between the endocannabinoid, gamma-aminobutyric acid, and glutamate systems and their individual and interactive effects on neural oscillations provide a plausible mechanism underlying the psychotomimetic effects of

  10. Laboratory and Physical Modelling of Building Ventilation Flows

    NASA Astrophysics Data System (ADS)

    Hunt, Gary

    2001-11-01

    Heating and ventilating buildings accounts for a significant fraction of the total energy budget of cities and an immediate challenge in building physics is for the design of sustainable, low-energy buildings. Natural ventilation provides a low-energy solution as it harness the buoyancy force associated with temperature differences between the internal and external environment, and the wind to drive a ventilating flow. Modern naturally-ventilated buildings use innovative design solutions, e.g. glazed atria and solar chimneys, to enhance the ventilation and demand for these and other designs has far outstripped our understanding of the fluid mechanics within these buildings. Developing an understanding of the thermal stratification and movement of air provides a considerable challenge as the flows involve interactions between stratification and turbulence and often in complex geometries. An approach that has provided significant new insight into these flows and which has led to the development of design guidelines for architects and ventilation engineers is laboratory modelling at small-scale in water tanks combined with physical modelling. Density differences to drive the flow in simplified plexiglass models of rooms or buildings are provided by fresh and salt water solutions, and wind flow is represented by a mean flow in a flume tank. In tandom with the experiments, theoretical models that capture the essential physics of these flows have been developed in order to generalise the experimental results to a wide range of typical building geometries and operating conditions. This paper describes the application and outcomes of these modelling techniques to the study of a variety of natural ventilation flows in buildings.

  11. Case Studies in Sustainability Used in an Introductory Laboratory Course to Enhance Laboratory Instruction

    ERIC Educational Resources Information Center

    Luster-Teasley, Stephanie; Hargrove-Leak, Sirena; Gibson, Willietta; Leak, Roland

    2017-01-01

    This educational research seeks to develop novel laboratory modules by using Case Studies in the Science Teaching method to introduce sustainability and environmental engineering laboratory concepts to 21st century learners. The increased interest in "going green" has led to a surge in the number of engineering students studying…

  12. [External quality assessment in clinical biochemistry laboratories: pilot study in 11 laboratories of Lomé (Togo)].

    PubMed

    Kouassi, Kafui; Fétéké, Lochina; Assignon, Selom; Dorkenoo, Ameyo; Napo-Koura, Gado

    2015-01-01

    This study aims to evaluate the performance of a few biochemistry analysis and make recommendations to the place of the stakeholders. It is a cross-sectional study conducted between the October 1(st), 2012 and the July 31, 2013 bearing on the results of 5 common examinations of clinical biochemistry, provided by 11 laboratories volunteers opening in the public and private sectors. These laboratories have analysed during the 3 cycles, 2 levels (medium and high) of serum concentration of urea, glucose, creatinine and serum aminotransferases. The performance of laboratories have been determined from the acceptable limits corresponding to the limits of total errors, defined by the French Society of Clinical Biology (SFBC). A system of internal quality control is implemented by all laboratories and 45% of them participated in international programs of external quality assessment (EQA). The rate of acceptable results for the entire study was of 69%. There was a significant difference (p<0.002) between the performance of the group of laboratories engaged in a quality approach and the group with default implementation of the quality approach. Also a significant difference was observed between the laboratories of the central level and those of the peripheral level of our health system (p<0.047). The performance of the results provided by the laboratories remains relatively unsatisfactory. It is important that the Ministry of Health put in place a national program of EQA with mandatory participation.

  13. Investigation of the Use of Geobags to Immobilize Submerged Munitions: A Report on the Concept, Development, and Testing

    DTIC Science & Technology

    2013-09-01

    Halls Ferry Road; Bldg 3270; RM 1810 Vicksburg, MS 39180 Raymond S. Chapman Coastal and Hydraulics Laboratory U.S. Army Engineer Research and...11  Figure 6. Olmsted 1:5 scale hydraulic flume, Phase 2 test bed...Bailey, Environmental Engineering Branch (EEB) of EPED; Andy Martin, EEB; Dr. Ray Chapman, ERDC Coastal and Hydraulics Laboratory (CHL); and Pam

  14. Standardization of Laboratory Methods for the PERCH Study

    PubMed Central

    Karron, Ruth A.; Morpeth, Susan C.; Bhat, Niranjan; Levine, Orin S.; Baggett, Henry C.; Brooks, W. Abdullah; Feikin, Daniel R.; Hammitt, Laura L.; Howie, Stephen R. C.; Knoll, Maria Deloria; Kotloff, Karen L.; Madhi, Shabir A.; Scott, J. Anthony G.; Thea, Donald M.; Adrian, Peter V.; Ahmed, Dilruba; Alam, Muntasir; Anderson, Trevor P.; Antonio, Martin; Baillie, Vicky L.; Dione, Michel; Endtz, Hubert P.; Gitahi, Caroline; Karani, Angela; Kwenda, Geoffrey; Maiga, Abdoul Aziz; McClellan, Jessica; Mitchell, Joanne L.; Morailane, Palesa; Mugo, Daisy; Mwaba, John; Mwansa, James; Mwarumba, Salim; Nyongesa, Sammy; Panchalingam, Sandra; Rahman, Mustafizur; Sawatwong, Pongpun; Tamboura, Boubou; Toure, Aliou; Whistler, Toni; O’Brien, Katherine L.; Murdoch, David R.

    2017-01-01

    Abstract The Pneumonia Etiology Research for Child Health study was conducted across 7 diverse research sites and relied on standardized clinical and laboratory methods for the accurate and meaningful interpretation of pneumonia etiology data. Blood, respiratory specimens, and urine were collected from children aged 1–59 months hospitalized with severe or very severe pneumonia and community controls of the same age without severe pneumonia and were tested with an extensive array of laboratory diagnostic tests. A standardized testing algorithm and standard operating procedures were applied across all study sites. Site laboratories received uniform training, equipment, and reagents for core testing methods. Standardization was further assured by routine teleconferences, in-person meetings, site monitoring visits, and internal and external quality assurance testing. Targeted confirmatory testing and testing by specialized assays were done at a central reference laboratory. PMID:28575358

  15. [Quality Management and Quality Specifications of Laboratory Tests in Clinical Studies--Challenges in Pre-Analytical Processes in Clinical Laboratories].

    PubMed

    Ishibashi, Midori

    2015-01-01

    The cost, speed, and quality are the three important factors recently indicated by the Ministry of Health, Labour and Welfare (MHLW) for the purpose of accelerating clinical studies. Based on this background, the importance of laboratory tests is increasing, especially in the evaluation of clinical study participants' entry and safety, and drug efficacy. To assure the quality of laboratory tests, providing high-quality laboratory tests is mandatory. For providing adequate quality assurance in laboratory tests, quality control in the three fields of pre-analytical, analytical, and post-analytical processes is extremely important. There are, however, no detailed written requirements concerning specimen collection, handling, preparation, storage, and shipping. Most laboratory tests for clinical studies are performed onsite in a local laboratory; however, a part of laboratory tests is done in offsite central laboratories after specimen shipping. As factors affecting laboratory tests, individual and inter-individual variations are well-known. Besides these factors, standardizing the factors of specimen collection, handling, preparation, storage, and shipping, may improve and maintain the high quality of clinical studies in general. Furthermore, the analytical method, units, and reference interval are also important factors. It is concluded that, to overcome the problems derived from pre-analytical processes, it is necessary to standardize specimen handling in a broad sense.

  16. Self-formed meandering river created in the laboratory using an upstream migrating boundary

    NASA Astrophysics Data System (ADS)

    van Dijk, W. M.; van de Lageweg, W. I.; Kleinhans, M. G.

    2010-12-01

    Braided rivers are relatively easily formed in the laboratory, whereas self-formed meandering rivers in the lab have proven very difficult to form, indicating a lack of understanding of the necessary and sufficient conditions for meandering. Our objective is to create self-formed dynamic meandering rivers and floodplains in a laboratory. Early experiments attempted to initiate meandering with upstream inflow at a fixed angle different from the general flow direction. The resulting bends were fixed at one position, which is not the dynamic meandering observed in nature. Another important condition for meandering is to have banks stronger than the non-cohesive bed sediment, which has been attained by growing vegetation. Furthermore, finer or light-weight sediment has been used to let chute channels fill up where otherwise multi-thread channels would have evolved, which is braiding. Yet the fixed-angle inflow kept meander migration and channel belt width and complexity limited. We accomplished dynamic meandering in the laboratory by using an upstream migrating boundary, which simulates a meander migrating into the flume. Our experiments were conducted in a circulated flume of 11x6 meter, with a constant discharge and sediment feed consisting of a sediment mixture ranging from silt to fine gravel (Kleinhans et al., 2010, this conference). The downstream boundary is a lake into which the river built a branched fan delta (Van de Lageweg et al., 2010, this conference). The morphology was recorded by high-resolution (0.5 mm) line-laser scanning and digital Single Lens Reflex (SLR) camera used for channel-floodplain segmentation and particle size estimation, at an interval of 8 hours. Furthermore a large number of smaller-scale auxiliary experiments were conducted to explore meandering tendency in a large range of parameters. Initial alternate ‘forced’ bars were formed at fixed positions with low sinuosity when the upstream boundary was at one fixed position. Migration

  17. Use of waste cellophane in the control of sediment : Final report.

    DOT National Transportation Integrated Search

    1978-01-01

    Based on laboratory flume tests, it was concluded that waste cellophane could be used effectively for trapping and filtering waterborne sediment. It was also priced competitively and, like straw and burlap, it was found to be biodegradable in a soil ...

  18. Flume experiments elucidate relationships between stream morphology, hyporheic residence time, and nitrous oxide production

    NASA Astrophysics Data System (ADS)

    Quick, Annika; Farrell, Tiffany B.; Reeder, William Jeffrey; Feris, Kevin P.; Tonina, Daniele; Benner, Shawn G.

    2015-04-01

    The hyporheic zone is a potentially important producer of nitrous oxide, a powerful greenhouse gas. The location and magnitude of nitrous oxide generation within the hyporheic zone involves complex interactions between multiple nitrogen species, redox conditions, microbial communities, and hydraulics. To better understand nitrous oxide generation and emissions from streams, we conducted large-scale flume experiments in which we monitored pore waters along hyporheic flow paths within stream dune structures. Measurements of dissolved oxygen, ammonia, nitrate, nitrite, and dissolved nitrous oxide showed distinct spatial relationships reflecting redox changes along flow paths. Using residence times along a flow path, clear trends in oxygen conditions and nitrogen species were observed. Three dune sizes were modeled, resulting in a range of residence times, carbon reactivity levels and respiration rates. We found that the magnitude and location of nitrous oxide production in the hyporheic zone is related to nitrate loading, dune morphology, and residence time. Specifically, increasing exogenous nitrate levels in surface water to approximately 3 mg/L resulted in an increase in dissolved N2O concentrations greater than 500% (up to 10 µg/L N-N2O) in distinct zones of specific residence times. We also found, however, that dissolved N2O concentrations decreased to background levels further along the flow path due to either reduction of nitrous oxide to dinitrogen gas or degassing. The decrease in measurable N2O along a flow path strongly suggests an important relationship between dune morphology, residence time, and nitrous oxide emissions from within stream sediments. Relating streambed morphology and loading of nitrogen species allows for prediction of nitrous oxide production in the hyporheic zone of natural systems.

  19. Survival and behavioral effects of exposure to a hydrokinetic turbine on juvenile Atlantic salmon and adult American shad

    USGS Publications Warehouse

    Castro-Santos, Theodore R.; Haro, Alex

    2015-01-01

    This paper describes a series of experiments designed to measure the effect of exposure to a full-scale, vertical axis hydrokinetic turbine on downstream migrating juvenile Atlantic salmon (N=75) and upstream migrating adult American shad (N=208). Controlled studies were performed in a large-scale, open-channel flume, and all individuals approached the turbine under volitional control. No injuries were observed, and there was no measurable increase in mortality associated with turbine passage. Exposure to the turbine elicited behavioral responses from both species, however, with salmon passing primarily over the downrunning blades. Shad movement was impeded by the device, as indicated by fewer attempts of shorter duration and reduced distance of ascent up the flume. More work should be performed in both laboratory and field conditions to determine to what extent these effects are likely to influence free-swimming fish.

  20. LABORATORY SCALE STEAM INJECTION TREATABILITY STUDIES

    EPA Science Inventory

    Laboratory scale steam injection treatability studies were first developed at The University of California-Berkeley. A comparable testing facility has been developed at USEPA's Robert S. Kerr Environmental Research Center. Experience has already shown that many volatile organic...

  1. Characterization of bedload transport in steep-slope streams

    NASA Astrophysics Data System (ADS)

    Mettra, F.; Heyman, J.; Ancey, C.

    2012-04-01

    Large fluctuations in the sediment transport rate are observed in rivers, particularly in mountain streams at intermediate flow rates. These fluctuations seem to be, to some degree, correlated to the formation and migration of bedforms. Today the central question is still how to understand and account for the strong bedload variability. Recent experimental studies shed new light on the processes. The objective of this presentation is to show some of our results. To understand the behavior and the origins of sediment transport rate fluctuations in the case of steep-slope streams, we conducted laboratory experiments in a 3-m long, 8-cm wide, transparent flume. The experimental parameters are the flume inclination, flow rate and sediment input rate. Well-sorted natural gravel (8.5 mm mean diameter) were used. We focused on two-dimensional flows and incipient bedforms (i.e., for flow rates just above the threshold of incipient motion). A technique based on accelerometers was developed to record every particle passing through the flume outlet (more specifically, we measured the vibrations of a metallic slab, which was impacted by the falling particles). Analysis of bedload transport rates was then possible on all time scales. Moreover, the bed and flow were monitored using 2 cameras. We computed bed elevation, water depth and erosion/deposition at high temporal and spatial rates from camera shots (one image per second during several hours or days). In our laboratory experiments, the fluctuations of the sediment rate were large even for steady flow conditions involving well-sorted particles. Time series exhibited fluctuations at all scales and displayed long range correlations with a Hurst exponent close to 0.8. The results were compared for different input solid discharges. The main bedforms observed in our flume were anti-dunes migrating upstream. Bedform formation and propagation showed intermittency with pulses (high activity) followed by long sequences of low

  2. Turning the tide: comparison of tidal flow by periodic sea level fluctuation and by periodic bed tilting in scaled landscape experiments of estuaries

    NASA Astrophysics Data System (ADS)

    Kleinhans, Maarten G.; van der Vegt, Maarten; Leuven, Jasper; Braat, Lisanne; Markies, Henk; Simmelink, Arjan; Roosendaal, Chris; van Eijk, Arjan; Vrijbergen, Paul; van Maarseveen, Marcel

    2017-11-01

    Analogue models or scale experiments of estuaries and short tidal basins are notoriously difficult to create in the laboratory because of the difficulty to obtain currents strong enough to transport sand. Our recently discovered method to drive tidal currents by periodically tilting the entire flume leads to intense sediment transport in both the ebb and flood phase, causing dynamic channel and shoal patterns. However, it remains unclear whether tilting produces periodic flows with characteristic tidal properties that are sufficiently similar to those in nature for the purpose of landscape experiments. Moreover, it is not well understood why the flows driven by periodic sea level fluctuation, as in nature, are not sufficient for morphodynamic experiments. Here we compare for the first time the tidal currents driven by sea level fluctuations and by tilting. Experiments were run in a 20 × 3 m straight flume, the Metronome, for a range of tilting periods and with one or two boundaries open at constant head with free inflow and outflow. Also, experiments were run with flow driven by periodic sea level fluctuations. We recorded surface flow velocity along the flume with particle imaging velocimetry and measured water levels along the flume. We compared the results to a one-dimensional model with shallow flow equations for a rough bed, which was tested on the experiments and applied to a range of length scales bridging small experiments and large estuaries. We found that the Reynolds method results in negligible flows along the flume except for the first few metres, whereas flume tilting results in nearly uniform reversing flow velocities along the entire flume that are strong enough to move sand. Furthermore, tidal excursion length relative to basin length and the dominance of friction over inertia is similar in tidal experiments and reality. The sediment mobility converges between the Reynolds method and tilting for flumes hundreds of metres long, which is impractical

  3. Ability of One-Dimensional Hairsine-Rose Erosion Model to Predict Sediment Transport over a Soil with Significant Surface Stones

    NASA Astrophysics Data System (ADS)

    Jomaa, S.; Barry, D. A.; Sander, G. C.; Parlange, J.-Y.; Heng, B. C. P.; Tromp-van Meerveld, H. J.

    2010-05-01

    Surface stones affect erosion rates by reducing raindrop-driven detachment and protecting the original soil against overland flow induced-hydraulic stress. Numerous studies have shown that the effect of surface stones on erosion depends on both the stone characteristics (e.g., size, distribution) and the soil properties. The aim of this study was (i) to quantify how the stone characteristics can affect the total sediment concentration and the concentrations of the individual size classes, (ii) to test if stones affect preferentially a particular size class within the eroded sediment and (iii) to determine whether the 1D Hairsine-Rose (H-R) erosion model can represent the experimental data. A series of laboratory experiments were conducted using the 2 m × 6 m EPFL erosion flume for a high rainfall intensity (60 mm/h) event on a gentle slope (2.2%). The flume was divided into two identical 1-m wide flumes. This separation was done to allow simultaneous replicate experiments. Experiments were conducted with different configurations and scenarios (stone coverage, size and emplacement). Three coverage proportions (20%, 40%, and 70%), two stone diameters (3-4 and 6-7 cm) and two emplacement types (topsoil and partially embedded) were tested. For each experiment, the total sediment concentration, the concentration for the individual size classes, and the flume discharge were measured. Infiltration rates were measured at different depths and locations. A high resolution laser scanner provided details of the surface change due to erosion during the experiments. This technique allowed us to quantify the spatial distribution of eroded soil and to understand better if sediment transport is 1D or rather 2D over the flumes. The one-dimensional Hairsine-Rose (H-R) erosion model was used to fit the integrated data and to provide estimates of the parameters. The ability of the 1D H-R model to predict the measured sediment concentrations in the presence of stones in the soil matrix

  4. [Study of quality of a branch laboratory--an opinion of a laboratory manager].

    PubMed

    Yazawa, Naoyuki

    2006-11-01

    At the stage of establishing a branch laboratory, quality evaluation is extremely difficult. Even the results of a control survey by the headquarters of the branch laboratory are unhelpful. For a clinical laboratory, the most important function is to provide reliable data all the time, and to maintain the reliability of clinical doctors with informed responses. We mostly refer to control surveys and daily quality control data to evaluate a clinical laboratory, but we rarely check its fundamental abilities, such as planning events, preserving statistical data about the standard range, using the right method for quality control and others. This is generally disregarded and it is taken for granted that they will be correct the first time. From my six years of experience working with X's branch laboratory, I realized that there might be some relation between the quality of a branch laboratory and the fundamental abilities of the company itself. I would never argue that all branch laboratories are ineffective, but they should be conscious of fundamental activities. The referring laboratory, not the referral laboratory, should be responsible for ensuring that the referral laboratory's examination results and findings are correct.

  5. Groundwater sapping valleys: Experimental studies, geological controls and implications to the interpretation of valley networks on Mars

    NASA Technical Reports Server (NTRS)

    Kochel, R. Craig

    1988-01-01

    An integrated approach using experimental laboratory models, field studies of terrestrial analogs, and remote studies of terrestrial field sites were applied to the goals of understanding the nature and morphology of valley networks formed by groundwater sapping. In spite of problems with scaling, the experimental studies provide valuable insights into concepts relating to the initiation, development, and evolution of valleys by groundwater sapping. These investigations are also aimed at developing geomorphic criteria for distinguishing valleys formed by surface runoff from those formed by groundwater sapping processes. Channels that were field classified as sapping vs. runoff were successfully distinguished using statistical analysis of their respective morphologies; therefore, it may be possible to use similar techniques to interpret channel genesis on Mars. The terrestrial and flume studies provide the ground truth dataset which can be used (and will be during the present year) to help interpret the genesis of valley networks on Mars.

  6. Laboratory studies in ultraviolet solar physics

    NASA Technical Reports Server (NTRS)

    Parkinson, W. H.; Kohl, J. L.; Gardner, L. D.; Raymond, J. C.; Smith, P. L.

    1991-01-01

    The research activity comprised the measurement of basic atomic processes and parameters which relate directly to the interpretation of solar ultraviolet observations and to the development of comprehensive models of the component structures of the solar atmosphere. The research was specifically directed towards providing the relevant atomic data needed to perform and to improve solar diagnostic techniques which probe active and quiet portions of the solar chromosphere, the transition zone, the inner corona, and the solar wind acceleration regions of the extended corona. The accuracy with which the physical conditions in these structures can be determined depends directly on the accuracy and completeness of the atomic and molecular data. These laboratory data are used to support the analysis programs of past and current solar observations (e.g., the Orbiting solar Observatories, the Solar Maximum Mission, the Skylab Apollo Telescope Mount, and the Naval Research Laboratory's rocket-borne High Resolution Telescope and Spectrograph). In addition, we attempted to anticipate the needs of future space-borne solar studies such as from the joint ESA/NASA Solar and Heliospheric Observatory (SOHO) spacecraft. Our laboratory activities stressed two categories of study: (1) the measurement of absolute rate coefficients for dielectronic recombination and electron impact excitation; and (2) the measurement of atomic transition probabilities for solar density diagnostics. A brief summary of the research activity is provided.

  7. Sediment dynamics in shallow Lake Markermeer, The Netherlands: field/laboratory surveys and first results for a 3-D suspended solids model.

    PubMed

    Kelderman, P; De Rozari, P; Mukhopadhyay, S; Ang'weya, R O

    2012-01-01

    In 2007/08, a study was undertaken on sediment dynamics in shallow Lake Markermeer, The Netherlands. Firstly, the sediment characteristics median grain size, mud content and loss on ignition showed a spatial as well as water depth related pattern indicating wind-induced sediment transport. Sediment dynamics were investigated in a sediment trap field survey at two stations. Sediment yields, virtually all coming from sediment resuspension, were significantly correlated with wind speeds. Resuspension rates for Lake Markermeer were very high, viz. ca. 1,000 g/m(2)day as an annual average, leading to high suspended solids (SS) contents, due to the large lake area and its shallowness (high 'Dynamic Ratio'). Sediment resuspension behaviour was further investigated in preliminary laboratory experiments using a 'micro-flume', applying increasing water currents onto five Lake Markermeer sediments. Resuspension showed a clear exponential behaviour. Finally, a 3-D model was set up for water quality and SS contents in Lake Markermeer; first results showed a good agreement between modelled and actual SS contents. Construction of artificial islands and dams will reduce wind fetches and may be expected to cause a substantial decrease in lake water turbidity.

  8. Spatial patterns of streambed morphology around woody debris: flume experiments and field observations on the effects of woody debris on streambed morphology

    NASA Astrophysics Data System (ADS)

    Leung, V.; Montgomery, D. R.

    2010-12-01

    The interactions between woody debris, fluid flow and sediment transport in rivers play a fundamental role in ecogeomorphology, affecting channel roughness, streambed morphology, and sediment transport and storage. In particular, woody debris increases the hydraulic and topographic complexity in rivers, leading to a greater diversity of aquatic habitats and an increase in the number of large pools that are important fish habitat and breeding grounds. In the past decade, engineered logjams have become an increasingly used tool in river management for simultaneously decreasing the rate of riverbank migration and improving aquatic habitat. Sediment deposits around woody debris build up riverbanks and counteract bank migration caused by erosion. Previous experiments of flow visualization around model woody debris suggest the amount of sediment scour and deposition are primarily related to the presence of roots and the obstructional area of the woody debris. We present the results of field surveys and sediment transport experiments of streambed morphology around stationary woody debris on a mobile bed. These experiments test the effects of root presence, root geometry and log orientation of individual stationary trees on streambed morphology. The flume contains a deformable sediment bed of medium sand, and has subcritical and turbulent flow, corresponding to flow conditions found in nature. Field surveys on the Hoh River, WA, measure the local streambed morphology around woody debris (e.g. pool and gravel-bar length, width and depth), as well as woody debris characteristics (e.g. tree diameter, tree length, root diameter and root depth). We quantified the amount of local sediment scour and deposition around woody debris of varying sizes, geometries and orientations relative to flow. We find that: 1) the presence of roots on woody debris leads to greater areas of both sediment scour and deposition; and 2) the amount of sediment scour and deposition are related to the

  9. Experimental observations of granular debris flows

    NASA Astrophysics Data System (ADS)

    Ghilardi, P.

    2003-04-01

    Various tests are run using two different laboratory flumes with rectangular cross section and transparent walls. The grains used in a single experiment have an almost constant grain sizes; mean diameter ranges from 5 mm to 20 mm. In each test various measurements are taken: hydrograms, velocity distribution near the transparent walls and on the free surface, average flow concentration. Concentration values are measured taking samples. Velocity distributions are obtained from movies recorded by high speed video cameras capable of 350 frames per second; flow rates and depth hydrograms are computed from the same velocity distributions. A gate is installed at the beginning of one of the flumes; this gate slides normally to the bed and opens very quickly, reproducing a dam-break. Several tests are run using this device, varying channel slope, sediment concentration, initial mixture thickness before the gate. Velocity distribution in the flume is almost constant from left to right, except for the flow sections near the front. The observed discharges and velocities are less than those given by a classic dam break formula, and depend on sediment concentration. The other flume is fed by a mixture with constant discharge and concentration, and is mainly used for measuring velocity distributions when the flow is uniform, with both rigid and granular bed, and to study erosion/deposition processes near debris flow dams or other mitigation devices. The equilibrium slope of the granular bed is very close to that given by the classical equilibrium formulas for debris flow. Different deposition processes are observed depending on mixture concentration and channel geometry.

  10. The Essential Role for Laboratory Studies in Atmospheric Chemistry.

    PubMed

    Burkholder, James B; Abbatt, Jonathan P D; Barnes, Ian; Roberts, James M; Melamed, Megan L; Ammann, Markus; Bertram, Allan K; Cappa, Christopher D; Carlton, Annmarie G; Carpenter, Lucy J; Crowley, John N; Dubowski, Yael; George, Christian; Heard, Dwayne E; Herrmann, Hartmut; Keutsch, Frank N; Kroll, Jesse H; McNeill, V Faye; Ng, Nga Lee; Nizkorodov, Sergey A; Orlando, John J; Percival, Carl J; Picquet-Varrault, Bénédicte; Rudich, Yinon; Seakins, Paul W; Surratt, Jason D; Tanimoto, Hiroshi; Thornton, Joel A; Tong, Zhu; Tyndall, Geoffrey S; Wahner, Andreas; Weschler, Charles J; Wilson, Kevin R; Ziemann, Paul J

    2017-03-07

    Laboratory studies of atmospheric chemistry characterize the nature of atmospherically relevant processes down to the molecular level, providing fundamental information used to assess how human activities drive environmental phenomena such as climate change, urban air pollution, ecosystem health, indoor air quality, and stratospheric ozone depletion. Laboratory studies have a central role in addressing the incomplete fundamental knowledge of atmospheric chemistry. This article highlights the evolving science needs for this community and emphasizes how our knowledge is far from complete, hindering our ability to predict the future state of our atmosphere and to respond to emerging global environmental change issues. Laboratory studies provide rich opportunities to expand our understanding of the atmosphere via collaborative research with the modeling and field measurement communities, and with neighboring disciplines.

  11. A qualitative case study of instructional support for web-based simulated laboratory exercises in online college chemistry laboratory courses

    NASA Astrophysics Data System (ADS)

    Schulman, Kathleen M.

    This study fills a gap in the research literature regarding the types of instructional support provided by instructors in online introductory chemistry laboratory courses that employ chemistry simulations as laboratory exercises. It also provides information regarding students' perceptions of the effectiveness of that instructional support. A multiple case study methodology was used to carry out the research. Two online introductory chemistry courses were studied at two community colleges. Data for this study was collected using phone interviews with faculty and student participants, surveys completed by students, and direct observation of the instructional designs of instructional support in the online Blackboard web sites and the chemistry simulations used by the participating institutions. The results indicated that the instructors provided multiple types of instructional support that correlated with forms of effective instructional support identified in the research literature, such as timely detailed feedback, detailed instructions for the laboratory experiments, and consistency in the instructional design of lecture and laboratory course materials, including the chemistry lab simulation environment. The students in one of these courses identified the following as the most effective types of instructional support provided: the instructor's feedback, opportunities to apply chemistry knowledge in the chemistry lab exercises, detailed procedures for the simulated laboratory exercises, the organization of the course Blackboard sites and the chemistry lab simulation web sites, and the textbook homework web sites. Students also identified components of instructional support they felt were missing. These included a desire for more interaction with the instructor, more support for the simulated laboratory exercises from the instructor and the developer of the chemistry simulations, and faster help with questions about the laboratory exercises or experimental

  12. Flume experiments elucidate relationships between microbial genetics, nitrogen species and hydraulics in controlling nitrous oxide production in the hyporheic zone

    NASA Astrophysics Data System (ADS)

    Quick, A. M.; Farrell, T. B.; Reeder, W. J.; Feris, K. P.; Tonina, D.; Benner, S. G.

    2014-12-01

    The hyporheic zone is a potentially important producer of nitrous oxide, a powerful greenhouse gas. The location and magnitude of nitrous oxide generation within the hyporheic zone involves complex interactions between multiple nitrogen species, redox conditions, microbial communities, and hydraulics. To better understand nitrous oxide generation and emissions from streams, we conducted large-scale flume experiments in which we monitored pore waters along hyporheic flow paths within stream dune structures. Measured dissolved oxygen, ammonia, nitrate, nitrite, and dissolved nitrous oxide showed distinct spatial relationships reflecting redox changes along flow paths. Denitrifying genes (nosZ, nirS, and nirK), determined using qPCR, were spatially associated with abundances of nitrogen species. Using residence times along a flow path, clear trends in oxygen conditions, genes encoding for microbial catalysis, and nitrogen species were observed. Hotspots of targeted genes correlated with hotspots for conversion of nitrogen species, including nitrous oxide production and conversion to dinitrogen. Trends were apparent regardless of dune size, allowing for the possibility to apply observed relationships to multiple streambed morphologies. Relating streambed morphology and loading of nitrogen species allows for prediction of nitrous oxide production in the hyporheic zone.

  13. The Essential Role for Laboratory Studies in Atmospheric Chemistry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burkholder, James B.; Abbatt, Jonathan P. D.; Barnes, Ian

    Laboratory studies of atmospheric chemistry characterize the nature of atmospherically relevant processes down to the molecular level, providing fundamental information used to assess how human activities drive environmental phenomena such as climate change, urban air pollution, ecosystem health, indoor air quality, and stratospheric ozone depletion. Laboratory studies have a central role in addressing the incomplete fundamental knowledge of atmospheric chemistry. This paper highlights the evolving science needs for this community and emphasizes how our knowledge is far from complete, hindering our ability to predict the future state of our atmosphere and to respond to emerging global environmental change issues. Finally,more » laboratory studies provide rich opportunities to expand our understanding of the atmosphere via collaborative research with the modeling and field measurement communities, and with neighboring disciplines.« less

  14. Laboratory Information Management System (LIMS): A case study

    NASA Technical Reports Server (NTRS)

    Crandall, Karen S.; Auping, Judith V.; Megargle, Robert G.

    1987-01-01

    In the late 70's, a refurbishment of the analytical laboratories serving the Materials Division at NASA Lewis Research Center was undertaken. As part of the modernization efforts, a Laboratory Information Management System (LIMS) was to be included. Preliminary studies indicated a custom-designed system as the best choice in order to satisfy all of the requirements. A scaled down version of the original design has been in operation since 1984. The LIMS, a combination of computer hardware, provides the chemical characterization laboratory with an information data base, a report generator, a user interface, and networking capabilities. This paper is an account of the processes involved in designing and implementing that LIMS.

  15. A Three-Year Feedback Study of a Remote Laboratory Used in Control Engineering Studies

    ERIC Educational Resources Information Center

    Chevalier, Amélie; Copot, Cosmin; Ionescu, Clara; De Keyser, Robin

    2017-01-01

    This paper discusses the results of a feedback study for a remote laboratory used in the education of control engineering students. The goal is to show the effectiveness of the remote laboratory on examination results. To provide an overview, the two applications of the remote laboratory are addressed: 1) the Stewart platform, and 2) the quadruple…

  16. Effects of Cohesive Sediment on Estuarine Morphology in Laboratory Scale Experiments

    NASA Astrophysics Data System (ADS)

    Braat, L.; Leuven, J.; Lokhorst, I.; Kleinhans, M. G.

    2017-12-01

    Mud plays a major role in forming and filling of river estuaries. River estuaries are typically build of sand and flanked by mudflats, which affect channel-shoal dynamics on time scales of centuries to millennia. In our research we aim to study the effects of mud on the shape and evolution of estuaries and where the largest effects occur. Recently a 20 m by 3 m flume (the Metronome) was developed at Utrecht University for tidal experiments. Complete estuaries are simulated in the Metronome by driving tidal flow by periodically tilting of the flume to counteract scaling problems. To simulate the effects of cohesive mud we supply nutshell grains to the system together with the river discharge. Three scenarios were tested, one with only sand, one with a low supply concentration of nutshell and one with a high concentration (left to right in figure).Estuaries that developed from an initial convergent shape are self-formed through bank erosion, continuous channel-shoal migration and bar and mud flat sedimentation (figure shows development over 15000 tilting cycles). The cohesive sediment deposits occur mainly on bars, but also on the flanks of the estuary and in abandoned channels. Due to its different erosional and depositional characteristics, the nutshell increases the elevation of the bars, which reduces storage and ebb-dominance and causes reduction of bar mobility and short cuts. These results agree with numerical model results. The large-scale effect is less widening of the estuary in the presence of mud and a decrease in channel-shoal migration, suggesting that mud confines estuary width in a similar manner as river floodplains.

  17. Knowledge Retention for Computer Simulations: A study comparing virtual and hands-on laboratories

    NASA Astrophysics Data System (ADS)

    Croom, John R., III

    The use of virtual laboratories has the potential to change physics education. These low-cost, interactive computer activities interest students, allow for easy setup, and give educators a way to teach laboratory based online classes. This study investigated whether virtual laboratories could replace traditional hands-on laboratories and whether students could retain the same long-term knowledge in virtual laboratories as compared to hands-on laboratories. This study is a quantitative quasi-experiment that used a multiple posttest design to determine if students using virtual laboratories would retain the same knowledge as students who performed hands-on laboratories after 9 weeks. The study was composed of 336 students from 14 school districts. Students had their performances on the laboratories and their retention of the laboratories compared to a series of factors that might have affected their retention using a pretest and two posttests, which were compared using a t test. The results showed no significant difference in short-term learning between the hands-on laboratory groups and virtual laboratory groups. There was, however, a significant difference (p = .005) between the groups in long-term retention; students in the hands-on laboratory groups retained more information than those in the virtual laboratory groups. These results suggest that long-term learning is enhanced when a laboratory contains a hands-on component. Finally, the results showed that both groups of students felt their particular laboratory style was superior to the alternative method. The findings of this study can be used to improve the integration of virtual laboratories into science curriculum.

  18. 21 CFR 58.185 - Reporting of nonclinical laboratory study results.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Reporting of nonclinical laboratory study results. 58.185 Section 58.185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Reporting of nonclinical laboratory study results. (a) A final report shall be prepared for each nonclinical...

  19. 21 CFR 58.185 - Reporting of nonclinical laboratory study results.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Reporting of nonclinical laboratory study results. 58.185 Section 58.185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Reporting of nonclinical laboratory study results. (a) A final report shall be prepared for each nonclinical...

  20. 21 CFR 58.185 - Reporting of nonclinical laboratory study results.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Reporting of nonclinical laboratory study results. 58.185 Section 58.185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Reporting of nonclinical laboratory study results. (a) A final report shall be prepared for each nonclinical...

  1. Sediment Transport of Fine Sand to Fine Gravel on Transverse Bed Slopes in Rotating Annular Flume Experiments

    NASA Astrophysics Data System (ADS)

    Baar, Anne W.; de Smit, Jaco; Uijttewaal, Wim S. J.; Kleinhans, Maarten G.

    2018-01-01

    Large-scale morphology, in particular meander bend depth, bar dimensions, and bifurcation dynamics, are greatly affected by the deflection of sediment transport on transverse bed slopes due to gravity and by secondary flows. Overestimating the transverse bed slope effect in morphodynamic models leads to flattening of the morphology, while underestimating leads to unrealistically steep bars and banks and a higher braiding index downstream. However, existing transverse bed slope predictors are based on a small set of experiments with a minor range of flow conditions and sediment sizes, and in practice models are calibrated on measured morphology. The objective of this research is to experimentally quantify the transverse bed slope effect for a large range of near-bed flow conditions with varying secondary flow intensity, sediment sizes (0.17-4 mm), sediment transport mode, and bed state to test existing predictors. We conducted over 200 experiments in a rotating annular flume with counterrotating floor, which allows control of the secondary flow intensity separate from the streamwise flow velocity. Flow velocity vectors were determined with a calibrated analytical model accounting for rough bed conditions. We isolated separate effects of all important parameters on the transverse slope. Resulting equilibrium transverse slopes show a clear trend with varying sediment mobilities and secondary flow intensities that deviate from known predictors depending on Shields number, and strongly depend on bed state and sediment transport mode. Fitted functions are provided for application in morphodynamic modeling.

  2. Successful Sampling Strategy Advances Laboratory Studies of NMR Logging in Unconsolidated Aquifers

    NASA Astrophysics Data System (ADS)

    Behroozmand, Ahmad A.; Knight, Rosemary; Müller-Petke, Mike; Auken, Esben; Barfod, Adrian A. S.; Ferré, Ty P. A.; Vilhelmsen, Troels N.; Johnson, Carole D.; Christiansen, Anders V.

    2017-11-01

    The nuclear magnetic resonance (NMR) technique has become popular in groundwater studies because it responds directly to the presence and mobility of water in a porous medium. There is a need to conduct laboratory experiments to aid in the development of NMR hydraulic conductivity models, as is typically done in the petroleum industry. However, the challenge has been obtaining high-quality laboratory samples from unconsolidated aquifers. At a study site in Denmark, we employed sonic drilling, which minimizes the disturbance of the surrounding material, and extracted twelve 7.6 cm diameter samples for laboratory measurements. We present a detailed comparison of the acquired laboratory and logging NMR data. The agreement observed between the laboratory and logging data suggests that the methodologies proposed in this study provide good conditions for studying NMR measurements of unconsolidated near-surface aquifers. Finally, we show how laboratory sample size and condition impact the NMR measurements.

  3. A Science Librarian in the Laboratory: A Case Study

    ERIC Educational Resources Information Center

    Tomaszewski, Robert

    2011-01-01

    A science librarian in the laboratory can become a "point of access" for database instruction and provide a learning opportunity for students to develop their information literacy skills. A case study describes how a librarian in an organic chemistry laboratory helps the class run smoothly and identifies the science librarian as an ally and a…

  4. Large-scale laboratory study of breaking wave hydrodynamics over a fixed bar

    NASA Astrophysics Data System (ADS)

    van der A, Dominic A.; van der Zanden, Joep; O'Donoghue, Tom; Hurther, David; Cáceres, Iván.; McLelland, Stuart J.; Ribberink, Jan S.

    2017-04-01

    A large-scale wave flume experiment has been carried out involving a T = 4 s regular wave with H = 0.85 m wave height plunging over a fixed barred beach profile. Velocity profiles were measured at 12 locations along the breaker bar using LDA and ADV. A strong undertow is generated reaching magnitudes of 0.8 m/s on the shoreward side of the breaker bar. A circulation pattern occurs between the breaking area and the inner surf zone. Time-averaged turbulent kinetic energy (TKE) is largest in the breaking area on the shoreward side of the bar where the plunging jet penetrates the water column. At this location, and on the bar crest, TKE generated at the water surface in the breaking process reaches the bottom boundary layer. In the breaking area, TKE does not reduce to zero within a wave cycle which leads to a high level of "residual" turbulence and therefore lower temporal variation in TKE compared to previous studies of breaking waves on plane beach slopes. It is argued that this residual turbulence results from the breaker bar-trough geometry, which enables larger length scales and time scales of breaking-generated vortices and which enhances turbulence production within the water column compared to plane beaches. Transport of TKE is dominated by the undertow-related flux, whereas the wave-related and turbulent fluxes are approximately an order of magnitude smaller. Turbulence production and dissipation are largest in the breaker zone and of similar magnitude, but in the shoaling zone and inner surf zone production is negligible and dissipation dominates.

  5. Zero-gravity cloud physics laboratory: Candidate experiments definition and preliminary concept studies

    NASA Technical Reports Server (NTRS)

    Eaton, L. R.; Greco, R. V.; Hollinden, A. B.

    1973-01-01

    The candidate definition studies on the zero-g cloud physics laboratory are covered. This laboratory will be an independent self-contained shuttle sortie payload. Several critical technology areas have been identified and studied to assure proper consideration in terms of engineering requirements for the final design. Areas include chambers, gas and particle generators, environmental controls, motion controls, change controls, observational techniques, and composition controls. This unique laboratory will allow studies to be performed without mechanical, aerodynamics, electrical, or other type techniques to support the object under study. This report also covers the candidate experiment definitions, chambers and experiment classes, laboratory concepts and plans, special supporting studies, early flight opportunities and payload planning data for overall shuttle payload requirements assessments.

  6. Laboratory Studies of Interstellar PAH Analogs

    NASA Technical Reports Server (NTRS)

    Salama, Farid; DeVincenzi, Donald (Technical Monitor)

    2000-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are now considered to be an important and ubiquitous component of the organic material in space. PAHs are found in a large variety of extraterrestrial materials such as interplanetary dust particles (IDPs) and meteoritic materials. PAHs are also good candidates to account for the infrared emission bands (UIRs) and the diffuse interstellar optical absorption bands (DIBs) detected in various regions of the interstellar medium. The recent observations made with the Infrared Space Observatory (ISO) have confirmed the ubiquitous nature of the UIR bands and their carriers. PAHs are though to form through chemical reactions in the outflow from carbon-rich stars in a process similar to soot formation. Once injected in the interstellar medium, PAHs are further processed by the interstellar radiation field, interstellar shocks and energetic particles. A major, dedicated, laboratory effort has been undertaken over the past years to measure the physical and chemical characteristics of these complex molecules and their ions under experimental conditions that mimic the interstellar conditions. These measurements require collision-free conditions where the molecules and ions are cold and chemically isolated. The spectroscopy of PAHs under controlled conditions represents an essential diagnostic tool to study the evolution of extraterrestrial PAHs. The Astrochemistry Laboratory program will be discussed through its multiple aspects: objectives, approach and techniques adopted, adaptability to the nature of the problem(s), results and implications for astronomy as well as for molecular spectroscopy. A review of the data generated through laboratory simulations of space environments and the role these data have played in our current understanding of the properties of interstellar PAHs will be presented. The discussion will also introduce the newest generation of laboratory experiments that are currently being developed in order to provide a

  7. Size stratification in a Gilbert delta due to a varying base level: flume experiments.

    NASA Astrophysics Data System (ADS)

    Chavarrias, Victor; Orru, Clara; Viparelli, Enrica; Vide, Juan Pedro Martin; Blom, Astrid

    2014-05-01

    A foreset-dominated Gilbert delta is a delta that is dominated by sediment avalanches (i.e., discontinuous grain flows) over its front. It forms when a river flows into a basin or sea characterized by a flow depth that is much larger than the one in the fluvial reach, and the conditions are such that the transported sediment passing the brinkpoint forms a wedge at the topmost part of the foreset, which results in avalanches down the foreset and a fining upward pattern within the foreset deposit. A Gilbert delta is typically described in terms of a low-slope topset (resulting from deposition over the fluvial reach), a steep-slope foreset (resulting from sediment avalanches over the lee face), and a bottomset (resulting from deposition of fine sediment passing the brinkpoint as suspended load). The objective of the present study is to gain insight into the mechanisms taking part in Gilbert delta formation and progradation under variable base level conditions. In order to do so, three flume experiments were conducted in which the water discharge and sediment feed rate were maintained constant but the base level varied between the experiments: (I) constant base level, (II) a gradually rising base level, and (III) a slowly varying base level. The stratigraphy within the delta deposit was measured using image analysis combined with particle coloring. A steady base level resulted in aggradation over the fluvial reach in order to maintain a slope required to transport the supplied sediment downstream. Sea level rise enhanced the amount of aggradation over the fluvial reach due to the presence of an M1 backwater curve. The aggrading flux to the substrate was slightly coarser than the fed sediment. The sediment at the base of the foreset deposit appeared to become coarser in streamwise direction. Eventually, a fall of the base level induced an M2 backwater curve over the fluvial reach that caused degradation of the fluvial reach. Base level fall first induced erosion of the

  8. Hysteretic sediment fluxes in rainfall-driven soil erosion

    NASA Astrophysics Data System (ADS)

    Cheraghi, Mohsen; Jomaa, Seifeddine; Sander, Graham C.; Barry, D. Andrew

    2017-04-01

    Hysteresis patterns of different sediment particle sizes were studied via a detailed laboratory study and modelling. Seven continuous rainfall events with stepwise- varying rainfall intensities (30, 37.5, 45, 60, 45, 37.5 and 30 mm h-1, each 20 min duration) were conducted using a 5-m × 2-m erosion flume. Flow rates and sediment concentration data were measured using flume discharge samples, and interpreted using the Hairsine and Rose (HR) soil erosion model. The total sediment concentration and concentrations of seven particle size classes (< 2, 2-20, 20-50, 50-100, 100-315, 315-1000 and > 1000 μm) were measured. For the total eroded soil and the finer particle sizes (< 2, 2-20 and 20-50 μm), there was a clockwise pattern in the sediment concentration versus discharge curves. However, as the particle size increased, concentrations tended to vary linearly with discharge. The HR model predictions for the total eroded soil and the finer particle size classes (up to 100 μm) were in good agreement with the experimental results. For the larger particles, the model provided qualitative agreement with the measurements but concentration values were different. In agreement with previous investigations using the HR model, these differences were attributed to the HR model's assumption of suspended sediment flow, which does not account for saltation and rolling motions. Keywords: Hysteresis effects, Sediment transport, Flume experiment, Splash soil erosion, Hairsine and Rose model, Particle Swarm Optimization.

  9. Summary of Adsorption Capacity and Adsorption Kinetics of Uranium and Other Elements on Amidoxime-based Adsorbents from Time Series Marine Testing at the Pacific Northwest National Laboratory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gill, Gary A.; Kuo, Li-Jung; Strivens, Jonathan E.

    The Pacific Northwest National Laboratory (PNNL) has been conducting marine testing of uranium adsorbent materials for the Fuel Resources Program, Department of Energy, Office of Nuclear Energy (DOE-NE) beginning in FY 2012. The marine testing program is being conducted at PNNL’s Marine Sciences Laboratory (MSL), located at Sequim Bay, along the coast of Washington. One of the main efforts of the marine testing program is the determination of adsorption capacity and adsorption kinetics for uranium and selected other elements (e.g. vanadium, iron, copper, nickel, and zinc) for adsorbent materials provided primarily by Oak Ridge National Laboratory (ORNL), but also includesmore » other Fuel Resources Program participants. This report summarizes the major marine testing results that have been obtained to date using time series sampling for 42 to 56 days using either flow-through column or recirculating flume exposures. The major results are highlighted in this report, and the full data sets are appended as a series of Excel spreadsheet files. Over the four year period (2012-2016) that marine testing of amidoxime-based polymeric adsorbents was conducted at PNNL’s Marine Science Laboratory, there has been a steady progression of improvement in the 56-day adsorbent capacity from 3.30 g U/kg adsorbent for the ORNL 38H adsorbent to the current best performing adsorbent prepared by a collaboration between the University of Tennessee and ORNL to produce the adsorbent SB12-8, which has an adsorption capacity of 6.56 g U/kg adsorbent. This nearly doubling of the adsorption capacity in four years is a significant advancement in amidoxime-based adsorbent technology and a significant achievement for the Uranium from Seawater program. The achievements are evident when compared to the several decades of work conducted by the Japanese scientists beginning in the 1980’s (Kim et al., 2013). The best adsorbent capacity reported by the Japanese scientists was 3.2 g U

  10. Laboratory-based versus non-laboratory-based method for assessment of cardiovascular disease risk: the NHANES I Follow-up Study cohort

    PubMed Central

    Gaziano, Thomas A; Young, Cynthia R; Fitzmaurice, Garrett; Atwood, Sidney; Gaziano, J Michael

    2008-01-01

    Summary Background Around 80% of all cardiovascular deaths occur in developing countries. Assessment of those patients at high risk is an important strategy for prevention. Since developing countries have limited resources for prevention strategies that require laboratory testing, we assessed if a risk prediction method that did not require any laboratory tests could be as accurate as one requiring laboratory information. Methods The National Health and Nutrition Examination Survey (NHANES) was a prospective cohort study of 14 407 US participants aged between 25–74 years at the time they were first examined (between 1971 and 1975). Our follow-up study population included participants with complete information on these surveys who did not report a history of cardiovascular disease (myocardial infarction, heart failure, stroke, angina) or cancer, yielding an analysis dataset N=6186. We compared how well either method could predict first-time fatal and non-fatal cardiovascular disease events in this cohort. For the laboratory-based model, which required blood testing, we used standard risk factors to assess risk of cardiovascular disease: age, systolic blood pressure, smoking status, total cholesterol, reported diabetes status, and current treatment for hypertension. For the non-laboratory-based model, we substituted body-mass index for cholesterol. Findings In the cohort of 6186, there were 1529 first-time cardiovascular events and 578 (38%) deaths due to cardiovascular disease over 21 years. In women, the laboratory-based model was useful for predicting events, with a c statistic of 0·829. The c statistic of the non-laboratory-based model was 0·831. In men, the results were similar (0·784 for the laboratory-based model and 0·783 for the non-laboratory-based model). Results were similar between the laboratory-based and non-laboratory-based models in both men and women when restricted to fatal events only. Interpretation A method that uses non-laboratory

  11. Sheet flow and suspended sediment due to wave groups in a large wave flume

    USGS Publications Warehouse

    Dohmen-Janssen, C. M.; Hanes, D.M.

    2005-01-01

    A series of sand bed experiments was carried out in the Large Wave Flume in Hannover, Germany as a component of the SISTEX99 experiment. The experiments focussed on the dynamic sediment response due to wave group forcing over a flat sand bed in order to improve understanding of cross-shore sediment transport mechanisms and determine sediment concentrations, fluxes and net transport rates under these conditions. Sediment concentrations were measured within the sheet flow layer (thickness in the order of 10 grain diameters) and in the suspension region (thickness in the order of centimetres). Within the sheet flow layer, the concentrations are highly coherent with the instantaneous near-bed velocities due to each wave within the wave group. However, in the suspension layer concentrations respond much more slowly to changes in near-bed velocity. At several centimetres above the bed, the suspended sediment concentrations vary on the time scale of the wave group, with a time delay relative to the peak wave within the wave group. The thickness of the sheet flow changes with time. It is strongly coherent with the wave forcing, and is not influenced by the history or sequence of the waves within the group. The velocity of the sediment was also measured within the sheet flow layer some of the time (during the larger wave crests of the group), and the velocity of the fluid was measured at several cm above the sheet flow layer. The grain velocity and concentration estimates can be combined to estimate the sediment flux. The estimates were found to be consistent with previous measurements under monochromatic waves. Under these conditions, without any significant mean current, the sediment flux within the sheet flow layer was found to greatly exceed the sediment flux in the suspension layer. As a result, net transport rates under wave groups are similar to those under monochromatic waves. ?? 2004 Elsevier Ltd. All rights reserved.

  12. Variability of creatinine measurements in clinical laboratories: results from the CRIC study.

    PubMed

    Joffe, Marshall; Hsu, Chi-yuan; Feldman, Harold I; Weir, Matthew; Landis, J R; Hamm, L Lee

    2010-01-01

    Estimating equations using serum creatinine (SCr) are often used to assess glomerular filtration rate (GFR). Such creatinine (Cr)-based formulae may produce biased estimates of GFR when using Cr measurements that have not been calibrated to reference laboratories. In this paper, we sought to examine the degree of this variation in Cr assays in several laboratories associated with academic medical centers affiliated with the Chronic Renal Insufficiency Cohort (CRIC) Study; to consider how best to correct for this variation, and to quantify the impact of such corrections on eligibility for participation in CRIC. Variability of Cr is of particular concern in the conduct of CRIC, a large multicenter study of subjects with chronic renal disease, because eligibility for the study depends on Cr-based assessment of GFR. A library of 5 large volume plasma specimens from apheresis patients was assembled, representing levels of plasma Cr from 0.8 to 2.4 mg/dl. Samples from this library were used for measurement of Cr at each of the 14 CRIC laboratories repetitively over time. We used graphical displays and linear regression methods to examine the variability in Cr, and used linear regression to develop calibration equations. We also examined the impact of the various calibration equations on the proportion of subjects screened as potential participants who were actually eligible for the study. There was substantial variability in Cr assays across laboratories and over time. We developed calibration equations for each laboratory; these equations varied substantially among laboratories and somewhat over time in some laboratories. The laboratory site contributed the most to variability (51% of the variance unexplained by the specimen) and variation with time accounted for another 15%. In some laboratories, calibration equations resulted in differences in eligibility for CRIC of as much as 20%. The substantial variability in SCr assays across laboratories necessitates calibration

  13. Scaling of Sediment Dynamics in a Reach-Scale Laboratory Model of a Sand-Bed Stream with Riparian Vegetation

    NASA Astrophysics Data System (ADS)

    Gorrick, S.; Rodriguez, J. F.

    2011-12-01

    A movable bed physical model was designed in a laboratory flume to simulate both bed and suspended load transport in a mildly sinuous sand-bed stream. Model simulations investigated the impact of different vegetation arrangements along the outer bank to evaluate rehabilitation options. Preserving similitude in the 1:16 laboratory model was very important. In this presentation the scaling approach, as well as the successes and challenges of the strategy are outlined. Firstly a near-bankfull flow event was chosen for laboratory simulation. In nature, bankfull events at the field site deposit new in-channel features but cause only small amounts of bank erosion. Thus the fixed banks in the model were not a drastic simplification. Next, and as in other studies, the flow velocity and turbulence measurements were collected in separate fixed bed experiments. The scaling of flow in these experiments was simply maintained by matching the Froude number and roughness levels. The subsequent movable bed experiments were then conducted under similar hydrodynamic conditions. In nature, the sand-bed stream is fairly typical; in high flows most sediment transport occurs in suspension and migrating dunes cover the bed. To achieve similar dynamics in the model equivalent values of the dimensionless bed shear stress and the particle Reynolds number were important. Close values of the two dimensionless numbers were achieved with lightweight sediments (R=0.3) including coal and apricot pips with a particle size distribution similar to that of the field site. Overall the moveable bed experiments were able to replicate the dominant sediment dynamics present in the stream during a bankfull flow and yielded relevant information for the analysis of the effects of riparian vegetation. There was a potential conflict in the strategy, in that grain roughness was exaggerated with respect to nature. The advantage of this strategy is that although grain roughness is exaggerated, the similarity of

  14. A new model for bed load sampler calibration to replace the probability-matching method

    Treesearch

    Robert B. Thomas; Jack Lewis

    1993-01-01

    In 1977 extensive data were collected to calibrate six Helley-Smith bed load samplers with four sediment particle sizes in a flume at the St. Anthony Falls Hydraulic Laboratory at the University of Minnesota. Because sampler data cannot be collected at the same time and place as ""true"" trap measurements, the ""probability-matching...

  15. Going GLP: Conducting Toxicology Studies in Compliance with Good Laboratory Practices.

    PubMed

    Carroll, Erica Eggers

    2016-01-01

    Good laboratory practice standards are US federal regulations enacted as part of the Federal Insecticide, Fungicide, and Rodenticide Act (40 CFR Part 160), the Toxic Substance Control Act (40 CFR Part 792), and the Good Laboratory Practice for Nonclinical Laboratory Studies (21 CFR Part 58) to support protection of public health in the areas of pesticides, chemicals, and drug investigations in response to allegations of inaccurate data acquisition. Essentially, good laboratory practices (GLPs) are a system of management controls for nonclinical research studies involving animals to ensure the uniformity, consistency, reliability, reproducibility, quality, and integrity of data collected as part of chemical (including pharmaceuticals) tests, from in vitro through acute to chronic toxicity tests. The GLPs were established in the United States in 1978 as a result of the Industrial Bio-Test Laboratory scandal which led to congressional hearings and actions to prevent fraudulent data reporting and collection. Although the establishment of infrastructure for GLPs compliance is labor-intensive and time-consuming, achievement and maintenance of GLP compliance ensures the accuracy of the data collected from each study, which is critical for defending results, advancing science, and protecting human and animal health. This article describes how and why those in the US Army Medical Department responsible for protecting the public health of US Army and other military personnel made the policy decision to have its toxicology laboratory achieve complete compliance with GLP standards, the first such among US Army laboratories. The challenges faced and how they were overcome are detailed.

  16. Semiconductor laser joint study program with Rome Laboratory

    NASA Astrophysics Data System (ADS)

    Schaff, William J.; Okeefe, Sean S.; Eastman, Lester F.

    1994-09-01

    A program to jointly study vertical-cavity surface emitting lasers (VCSEL) for high speed vertical optical interconnects (VOI) has been conducted under an ES&E between Rome Laboratory and Cornell University. Lasers were designed, grown, and fabricated at Cornell University. A VCSEL measurement laboratory has been designed, built, and utilized at Rome Laboratory. High quality VCSEL material was grown and characterized by fabricating conventional lateral cavity lasers that emitted at the design wavelength of 1.04 microns. The VCSEL's emit at 1.06 microns. Threshold currents of 16 mA at 4.8 volts were obtained for 30 microns diameter devices. Output powers of 5 mW were measured. This is 500 times higher power than from the light emitting diodes employed previously for vertical optical interconnects. A new form of compositional grading using a cosinusoidal function has been developed and is very successful for reducing diode series resistance for high speed interconnection applications. A flip-chip diamond package compatible with high speed operation of 16 VCSEL elements has been designed and characterized. A flip-chip device binding effort at Rome Laboratory was also designed and initiated. This report presents details of the one-year effort, including process recipes and results.

  17. An Exploratory Study of Objective Attainment in the Divergent Physics Laboratory.

    ERIC Educational Resources Information Center

    Lerch, Robert Donald

    Students enrolled in the introductory physics laboratory at New Mexico State University participated in this study. A stated set of objectives, developed by Dr. John M. Fowler of the Commission on College Physics, was used in the laboratory. This study attempted to measure student achievement based on the use of these objectives as opposed to the…

  18. Staffing benchmarks for clinical laboratories: a College of American Pathologists Q-Probes study of laboratory staffing at 98 institutions.

    PubMed

    Jones, Bruce A; Darcy, Teresa; Souers, Rhona J; Meier, Frederick A

    2012-02-01

    Publicly available information concerning laboratory staffing benchmarks is scarce. One of the few publications on this topic summarized the findings of a Q-Probes study performed in 2004. This publication reports a similar survey with data collected in 2010. To assess the relationship between staffing levels in specified laboratory sections and test volumes in these sections and quantify management span of control. The study defined 4 laboratory sections: anatomic pathology (including cytology), chemistry/hematology/immunology, microbiology, and transfusion medicine. It divided staff into 3 categories: management, nonmanagement (operational or bench staff), and doctoral (MD, PhD) supervisory staff. People in these categories were tabulated as full-time equivalents and exclusions specified. Tests were counted in uniform formats, specified for each laboratory section, according to Medicare rules for the bundling and unbundling of tests. Ninety-eight participating institutions provided data that showed significant associations between test volumes and staffing for all 4 sections. There was wide variation in productivity based on volume. There was no relationship between testing volume per laboratory section and management span of control. Higher productivity in chemistry/hematology/immunology was associated with a higher fraction of tests coming from nonacute care patients. In both the 2004 and 2010 studies, productivity was inseparably linked to test volume. Higher test volume was associated with higher productivity ratios in chemistry/hematology/immunology and transfusion medicine sections. The impact of various testing services on productivity is section-specific.

  19. Hiero-Dermato-Glyphics: Laboratory Study of the Skin

    ERIC Educational Resources Information Center

    Roark, Oakley F.

    1977-01-01

    Explains several laboratory exercises using the skin, including the mapping of receptors, counting of sweat glands, computation of total skin area, comparison of various animal skins, measurement of the palm triradius angle, and study of epidermal ridges (dermatoglyphics) in males and females. (CS)

  20. Laboratory Practices of Beginning Secondary Science Teachers: A Five-Year Study

    ERIC Educational Resources Information Center

    Wong, Sissy S.; Firestone, Jonah B.; Luft, Julie A.; Weeks, Charles B.

    2013-01-01

    During the beginning years of teaching, science teachers develop the knowledge and skills needed to design and implement science laboratories. In this regard, this quantitative study focused on the reported laboratory practices of 61 beginning secondary science teachers who participated in four different induction programs. The results…

  1. Developing Medicare Competitive Bidding: A Study of Clinical Laboratories

    PubMed Central

    Hoerger, Thomas J.; Meadow, Ann

    1997-01-01

    Competitive bidding to derive Medicare fees promises several advantages over administered fee systems. The authors show how incentives for cost savings, quality, and access can be incorporated into bidding schemes, and they report on a study of the clinical laboratory industry conducted in preparation for a bidding demonstration. The laboratory industry is marked by variable concentration across geographic markets and, among firms themselves, by social and economic heterogeneity. The authors conclude that these conditions can be accommodated by available bidding design options and by careful selection of bidding markets. PMID:10180003

  2. Sampling efficiency of the Moore egg collector

    USGS Publications Warehouse

    Worthington, Thomas A.; Brewer, Shannon K.; Grabowski, Timothy B.; Mueller, Julia

    2013-01-01

    Quantitative studies focusing on the collection of semibuoyant fish eggs, which are associated with a pelagic broadcast-spawning reproductive strategy, are often conducted to evaluate reproductive success. Many of the fishes in this reproductive guild have suffered significant reductions in range and abundance. However, the efficiency of the sampling gear used to evaluate reproduction is often unknown and renders interpretation of the data from these studies difficult. Our objective was to assess the efficiency of a modified Moore egg collector (MEC) using field and laboratory trials. Gear efficiency was assessed by releasing a known quantity of gellan beads with a specific gravity similar to that of eggs from representatives of this reproductive guild (e.g., the Arkansas River Shiner Notropis girardi) into an outdoor flume and recording recaptures. We also used field trials to determine how discharge and release location influenced gear efficiency given current methodological approaches. The flume trials indicated that gear efficiency ranged between 0.0% and 9.5% (n = 57) in a simple 1.83-m-wide channel and was positively related to discharge. Efficiency in the field trials was lower, ranging between 0.0% and 3.6%, and was negatively related to bead release distance from the MEC and discharge. The flume trials indicated that the gellan beads were not distributed uniformly across the channel, although aggregation was reduced at higher discharges. This clustering of passively drifting particles should be considered when selecting placement sites for an MEC; further, the use of multiple devices may be warranted in channels with multiple areas of concentrated flow.

  3. Laboratory studies of imitation/field studies of tradition: towards a synthesis in animal social learning.

    PubMed

    Galef, Bennett G

    2015-03-01

    Here I discuss: (1) historical precedents that have resulted in comparative psychologists accepting the two-action method as the "gold standard" in laboratory investigations of imitation learning, (2) evidence suggesting that the two-action procedure may not be adequate to answer questions concerning the role of imitation in the development of traditional behaviors of animals living in natural habitat, and (3) an alternative approach to the laboratory study of imitation that might increase the relevance of laboratory studies of imitation to the work of behavioral ecologists/primatologists interested in animal traditions and their relationship to human cumulative culture. This article is part of a Special Issue entitled: Tribute to Tom Zentall. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. A Manpower Study of Technical Personnel in Hospital Clinical Laboratories. Final Report.

    ERIC Educational Resources Information Center

    Harkness, James P., And Others

    As one of the efforts related to closing the gap between the growing demands for clinical laboratory workers and the supply of well-trained workers, the volume and quality of laboratory procedures and the general characteristics of workers in North Carolina hospitals were studied. Approaches to the study included tests on "unknowns" by…

  5. Knowledge, attitude, and practice (KAP) of 'teaching laboratory' technicians towards laboratory safety and waste management: a pilot interventional study.

    PubMed

    El-Gilany, A-H; El-Shaer, S; Khashaba, E; El-Dakroory, S A; Omar, N

    2017-06-01

    A quasi-experimental study was performed on 20 technicians working in the Faculty of Medicine, Mansoura University, Egypt. The knowledge, attitude, and practice (KAP) of laboratory technicians was measured before and two months after enrolling them in an intervention programme about laboratory best practice procedures. The programme addressed laboratory safety and medical waste management. The assessment was performed using a validated Arabic self-administered questionnaire. Pre- and post-intervention scores were compared using non-parametric tests. There are significant increases in the scores of KAP after implementation of the training programme. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  6. [Tuberculosis Laboratory Surveillance Network (TuLSA) study group. The first step for national tuberculosis laboratory surveillance: Ankara, 2011].

    PubMed

    Sezen, Figen; Albayrak, Nurhan; Özkara, Şeref; Karagöz, Alper; Alp, Alpaslan; Duyar Ağca, Filiz; İnan Süer, Asiye; Müderris, Tuba; Ceyhan, İsmail; Durmaz, Rıza; Ertek, Mustafa

    2015-04-01

    The most effective method for monitoring country-level drug resistance frequency and to implement the necessary control measures is the establishment of a laboratory-based surveillance system. The aim of this study was to summarize the follow up trend of the drug-resistant tuberculosis (TB) cases, determine the load of resistance and evaluate the capacities of laboratories depending on laboratory quality assurance system for the installation work of National Tuberculosis Laboratory Surveillance Network (TuLSA) which has started in Ankara in 2011. TuLSA studies was carried out under the coordination of National Tuberculosis Reference Laboratory (NRL) with the participation of TB laboratories and dispensaries. Specimens of TB patients, reported from health institutions, were followed in TB laboratories, and the epidemiological information was collected from the dispensaries. One isolate per patient with the drug susceptibility test (DST) results were sent to NRL from TB laboratories and in NRL the isolates were rechecked with the genotypical (MTBDRplus, Hain Lifescience, Germany) and phenotypical (MGIT 960, BD, USA) DST methods. Molecular epidemiological analysis were also performed by spoligotyping and MIRU/VNTR. Second-line DST was applied to the isolates resistant to rifampin. A total of 1276 patients were reported between January 1st to December 31th 2011, and 335 cases were defined as "pulmonary TB from Ankara province". The mean age of those patients was 43.4 ± 20 years, and 67.5% were male. Three hundred seventeen (94.6%) patients were identified as new cases. The average sample number obtained from pulmonary TB cases was 3.26 ± 2.88, and 229 (68.3%) of them was culture positive. DST was applied to all culture positive isolates; 90.4% (207/229) of cases were susceptible to the five drugs tested (ethambutol, isoniazid, pyrazinamide, rifampicin, streptomycin). Eight (3.5%) of the isolates were multidrug-resistant (MDR-TB), while no extensively drug

  7. Correlating field and laboratory rates of particle abrasion, Rio Medio, Sangre de Cristo Mountains, New Mexico

    NASA Astrophysics Data System (ADS)

    Polito, P. J.; Sklar, L. S.

    2006-12-01

    River bed sediments commonly fine downstream due to a combination of particle abrasion, selective transport of finer grains, and fining of the local sediment supply from hillslopes and tributaries. Particle abrasion rates can be directly measured in the laboratory using tumbling barrels and annular flumes, however, scaling experimental particle abrasion rates to the field has proven difficult due to the confounding effects of selective transport and local supply variations. Here we attempt to correlate laboratory and field rates of particle abrasion in a field setting where these confounding effects can be controlled. The Rio Medio, which flows westward from the crest of the Sangre de Cristo Mountains in north central New Mexico, is one of several streams studied by John P. Miller in the early 1960's. Several kilometers downstream of its headwaters, the river crosses the Picuris-Pecos fault. Upstream of the fault the river receives quartzite, sandstone and shale clasts from the Ortega Formation, while downstream sediments are supplied by the Embudo Granite. Because the upstream lithologies are not resupplied downstream of the fault, any observed fining of these clasts should be due only to abrasion and selective transport. We hypothesize that we can account for the effects of selective transport by comparing relative fining rates for the different upstream lithologies from both the field and a laboratory tumbler. By correlating laboratory abrasion rates with rock strength, we can predict the relative fining rates due solely to abrasion expected in the field; differences between the predicted and observed fining rates could then be attributed to selective transport. We used point counts to measure bed surface sediment grain size distributions at 15 locations along a 25 kilometer reach of the Rio Medio, beginning just downstream of the fault and ending upstream of a developed area with disturbed channel conditions. We recorded intermediate particle diameter as well

  8. Clinical laboratory studies of disinfection with Sporicidin.

    PubMed Central

    Isenberg, H D

    1985-01-01

    The clinical microbiology laboratory evaluation of disinfectants can serve as a guide for their application to reduce hospital-acquired infections. The use of Sporicidin, a glutaraldehyde-phenol formulation, was evaluated by the application of modified MIC and MBC determinations for standard organisms. In addition, the effect of this formulation on bacteria that may proliferate in water at ambient temperatures was studied. This investigation indicated that such studies can help the clinical microbiologist to guide the use of disinfectants and sterilants for the maintenance of a safe hospital environment. PMID:3932457

  9. An Experimental Study of a BSCS-Style Laboratory Approach for University General Biology.

    ERIC Educational Resources Information Center

    Leonard, William H.

    1983-01-01

    A Biological Sciences Curriculum Study (BSCS) inquiry approach for university general biology laboratory was tested against a well-established commercial program judged to be highly directive. The BSCS was found to be more effective in learning biology laboratory concepts than the commercial program as measured by a laboratory concepts test.…

  10. Safety in the Chemical Laboratory. Epidemiology of Accidents in Academic Chemistry Laboratories, Part 2. Accident Intervention Study, Legal Aspects, and Observations.

    ERIC Educational Resources Information Center

    Hellmann, Margaret A.; And Others

    1986-01-01

    Reports on a chemistry laboratory accident intervention study conducted throughout the state of Colorado. Addresses the results of an initial survey of institutions of higher learning. Discusses some legal aspects concerning academic chemistry accidents. Provides some observations about academic chemistry laboratory accidents on the whole. (TW)

  11. Tracer Studies In A Laboratory Beach Subjected To Waves

    EPA Science Inventory

    This work investigated the washout of dissolved nutrients from beaches due to waves by conducting tracer studies in a laboratory beach facility. The effects of waves were studied in the case where the beach was subjected to the tide, and that in which no tidal action was present...

  12. Preliminary study: Formaldehyde exposure in laboratories of Sharjah university in UAE

    PubMed Central

    Ahmed, Hafiz Omer

    2011-01-01

    Objectives Laboratory technicians, students, and instructors are at high risk, because they deal with chemicals including formaldehyde. Thus, this preliminary study was conducted to measure the concentration of formaldehyde in the laboratories of the University of Sharjah in UAE. Materials and Methods: Thirty-two air samples were collected and analyzed for formaldehyde using National Institute for Occupational Safety and Health (NIOSH) method 3500. In this method, formaldehyde reacts with chromotropic acid in the presence of sulfuric acid to form a colored solution. The absorbance of the colored solution is read in spectrophotometer at wavelength 580 nm and is proportional to the quantity of the formaldehyde in the solution. Results: For the anatomy laboratory and in the presence of the covered cadaver, the mean concentration of formaldehyde was found to be 0.100 ppm with a range of 0.095–0.105 ppm. Whereas for the other laboratories, the highest mean concentration of formaldehyde was 0.024 ppm in the general microbiology laboratory and the lowest mean concentration of formaldehyde was 0.001 ppm in the environmental health laboratory. The 8-hour (time-weighted average) concentration of formaldehyde was found to be ranging between 0.0003 ppm in environmental health laboratory and 0.026 ppm in the anatomy laboratory. Conclusions: The highest level of concentration of formaldehyde in the presence of the covered cadaver in anatomy laboratory exceeded the recommended ceiling standard established by USA-NIOSH which is 0.1 ppm, but below the ceiling standard established by American Conference of Governmental Industrial Hygienists which is 0.3 ppm. Thus, it is recommended that formaldehyde levels should be measured periodically specially during the dissection in the anatomy laboratory, and local exhaust ventilation system should be installed and personal protective equipment such as safety glass and gloves should be available and be used to prevent direct skin or eye

  13. [Quality assessment of microscopic examination in tuberculosis diagnostic laboratories: a preliminary study].

    PubMed

    Simşek, Hülya; Ceyhan, Ismail; Tarhan, Gülnur; Güner, Uğur

    2010-10-01

    Recently, the diagnosis of pulmonary tuberculosis (TB) has based on smear microscopy in the Direct Observed Treatment Strategy (DOTS) programme which provides the basis of treatment worldwide. Microscopic detection of AFB (Acid-Fast Bacilli) is one of the main components in the National TB Control Programmes (NTCP). Precision level in microscopy procedures and evaluations are the most important steps for accurate diagnosis of the disease and to initiate proper treatment. Therefore, the external quality assessment (EQA) is the most important implement to provide the reliability and validity of tests. In countries where NTCP are performed, this task is fulfilled by the National Reference Laboratories (NRL) according to the guidelines of the World Health Organization (WHO). For this purpose a pilot study was initiated by the central NRL of Turkey for EQA of AFB smear microscopy as part of the NTCP on January 1, 2005. A total of 5 laboratories of which 2 were district TB laboratories (A, B), 2 were tuberculosis control dispensaries (C, D), 1 was a national reference laboratory (E), participated in this study. Blind re-checking method (re-examination of randomly selected slides) was used for the evaluation, and the slides were sent to the central NRL with 3 months interval, four times a year, selected according to LQAS (Lot Quality Assurance Sampling) guides. In the re-evaluation of the slides, false positivity (FP), false negativity (FN) and quantification errors (QE) were noted. Laboratory A, sent totally 525 slides between January 1, 2005 and April 1, 2008. In the result of re-checking, 514 (97.9%) slides were found concordant, and 11 (2.1%) were discordant (10 FP, 1 FN). Laboratory B, participated in the study between October 1, 2005 and July 1, 2006 and of the 67 re-examined slides, 60 (89.5%) were concordant and 7 (10.5%) were discordant (2 FP, 0 FN, 5 QE). Laboratory C, sent 235 slides between January 1, 2005 and April 1, 2006; of them 218 (92.8%) were detected

  14. How toxic is coal ash? A laboratory toxicity case study

    DOE PAGES

    Sherrard, Rick M.; Carriker, Neil; Greeley, Jr., Mark Stephen

    2014-12-08

    Under a consent agreement among the Environmental Protection Agency (EPA) and proponents both for and against stricter regulation, EPA is to issue a new coal ash disposal rule by the end of 2014. Laboratory toxicity investigations often yield conservative estimates of toxicity because many standard test species are more sensitive than resident species, thus could provide information useful to the rule-making. However, few laboratory studies of coal ash toxicity are available; most studies reported in the literature are based solely on field investigations. In this paper, we describe a broad range of toxicity studies conducted for the Tennessee Valley Authoritymore » (TVA) Kingston ash spill, results of which help provide additional perspective on the toxicity of coal ash.« less

  15. Bed Load Variability and Morphology of Gravel Bed Rivers Subject to Unsteady Flow: A Laboratory Investigation

    NASA Astrophysics Data System (ADS)

    Redolfi, M.; Bertoldi, W.; Tubino, M.; Welber, M.

    2018-02-01

    Measurement and estimation of bed load transport in gravel bed rivers are highly affected by its temporal fluctuations. Such variability is primarily driven by the flow regime but is also associated with a variety of inherent channel processes, such as flow turbulence, grain entrainment, and bed forms migration. These internal and external controls often act at comparable time scales, and are therefore difficult to disentangle, thus hindering the study of bed load variability under unsteady flow regime. In this paper, we report on laboratory experiments performed in a large, mobile bed flume where typical hydromorphological conditions of gravel bed rivers were reproduced. Data from a large number of replicated runs, including triangular and square-wave hydrographs, were used to build a statistically sound description of sediment transport processes. We found that the inherent variability of bed load flux strongly depends on the sampling interval, and it is significantly higher in complex, wandering or braided channels. This variability can be filtered out by computing the mean response over the experimental replicates, which allows us to highlight two distinctive phenomena: (i) an overshooting (undershooting) response of the mean bed load flux to a sudden increase (decrease) of discharge, and (ii) a clockwise hysteresis in the sediment rating curve. We then provide an interpretation of these findings through a conceptual mathematical model, showing how both phenomena are associated with a lagging morphological adaptation to unsteady flow. Overall, this work provides basic information for evaluating, monitoring, and managing gravel transport in morphologically active rivers.

  16. Use of water towing tanks for aerodynamics and hydrodynamics

    NASA Technical Reports Server (NTRS)

    Gadelhak, Mohamed

    1987-01-01

    Wind tunnels and flumes have become standard laboratory tools for modeling a variety of aerodynamic and hydrodynamic flow problems. Less available, although by no means less useful, are facilities in which a model can be towed (or propelled) through air or water. This article emphasizes the use of the water towing tank as an experimental tool for aerodynamic and hydrodynamic studies. Its advantages and disadvantages over other flow rigs are discussed, and its usefullness is illustrated through many examples of research results obtained over the past few years in a typical towing tank facility.

  17. Predicting organic floc transport dynamics in shallow aquatic ecosystems: Insights from the field, the laboratory, and numerical modeling

    USGS Publications Warehouse

    Harvey, Judson W.; Noe, Gregory B.; Larsen, Laurel G.; Crimaldi, John P.

    2009-01-01

    Transport of particulate organic material can impact watershed sediment and nutrient budgets and can alter the geomorphologic evolution of shallow aquatic environments. Prediction of organic aggregate (“floc”) transport in these environments requires knowledge of how hydraulics and biota affect the entrainment, settling, and aggregation of particles. This study evaluated the aggregation and field transport dynamics of organic floc from a low‐gradient floodplain wetland with flow‐parallel ridges and sloughs in the Florida Everglades. Floc dynamics were evaluated in a rotating annular flume and in situ in the field. Under present managed conditions in the Everglades, floc is not entrained by mean flows but is suspended via biological production in the water column and bioturbation. Aggregation was a significant process affecting Everglades floc at high flume flow velocities (7.0 cm s−1) and during recovery from high flow; disaggregation was not significant for the tested flows. During moderate flows when floc dynamics are hydrodynamically controlled, it is possible to model floc transport using a single “operative floc diameter” that accurately predicts fluxes downstream and to the bed. In contrast, during high flows and recovery from high flows, aggregation dynamics should be simulated. When entrained by flow in open‐water sloughs, Everglades floc will be transported downstream in multiple deposition and reentrainment events but will undergo net settling when transported onto ridges of emergent vegetation. We hypothesize that net transport of material from open to vegetated areas during high flows is critical for forming and maintaining distinctive topographic patterning in the Everglades and other low‐gradient floodplains.

  18. An international study of how laboratories handle and evaluate patient samples after detecting an unexpected APTT prolongation.

    PubMed

    Ajzner, Éva; Rogic, Dunja; Meijer, Piet; Kristoffersen, Ann Helen; Carraro, Paolo; Sozmen, Eser; Faria, Ana Paula; Sandberg, Sverre

    2015-09-01

    An unexpectedly detected prolonged activated partial thromboplastin time (APTT) can be a harmless laboratory finding, but can also reflect a thrombotic tendency or a bleeding disorder. The assistance of laboratory professionals in the interpretation of an unexpectedly detected prolonged APTT (uAPTT) is often required. The way in which uAPTTs are evaluated in laboratories was assessed in this international study with the aim of determining whether laboratory professionals are able to fulfill this need. Postanalytical practices after uAPTT were investigated and the mixing study methodology (if used) was studied by circulating a case report with a questionnaire to staff in the invited laboratories. In addition, the interpretations of those staff regarding the presence or absence of inhibitors in three APTT mixing study scenarios were examined. Large within- and between-country variations were detected in both postanalytical practices and mixing study methodologies among the 990 responding laboratories, 90% of which were in 13 countries. Shortcomings regarding the investigation of uAPTTs leading to potentially incorrect or delayed clinical diagnoses were found in 88% of the laboratories. Of the laboratories to which the interpretative questions were sent, 49% interpreted all mixing study scenarios correctly. uAPTTs were investigated appropriately and all mixing study scenarios interpreted correctly in parallel in only 9.6% of the participating laboratories. The clinical requirement for the assistance of laboratory professionals in the interpretation of uAPTTs cannot be met at most of the participating laboratories. Laboratory professionals should be trained in the evaluation of ordinary laboratory tests, such as that for uAPTTs.

  19. Report of the Field and Laboratory Utilization Study Group. Appendix

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1975-12-01

    These appendices (ERDA organization and management, summary of other resources, and FLU study considerations/inputs) provide detailed and quantitative information in support of the findings and recommendations presented in the report of the field and laboratory utilization study group. (RWR)

  20. Understanding behavioral responses of fish to pheromones in natural freshwater environments

    USGS Publications Warehouse

    Johnson, Nicholas S.; Li, Weiming

    2010-01-01

    There is an abundance of experimental studies and reviews that describe odorant-mediated behaviors of fish in laboratory microcosms, but research in natural field conditions has received considerably less attention. Fish pheromone studies in laboratory settings can be highly productive and allow for controlled experimental designs; however, laboratory tanks and flumes often cannot replicate all the physical, physiological and social contexts associated with natural environments. Field experiments can be a critical step in affirming and enhancing understanding of laboratory discoveries and often implicate the ecological significance of pheromones employed by fishes. When findings from laboratory experiments have been further tested in field environments, often different and sometimes contradictory conclusions are found. Examples include studies of sea lamprey (Petromyzon marinus) mating pheromones and fish alarm substances. Here, we review field research conducted on fish pheromones and alarm substances, highlighting the following topics: (1) contradictory results obtained in laboratory and field experiments, (2) how environmental context and physiological status influences behavior, (3) challenges and constraints of aquatic field research and (4) innovative techniques and experimental designs that advance understanding of fish chemical ecology through field research.

  1. Laboratory and Space Plasma Studies

    NASA Astrophysics Data System (ADS)

    Hyman, Ellis

    1996-08-01

    The work performed by Science Applications International Corporation (SAIC), encompasses a wide range of topics in experimental, computational, and analytical laboratory and space plasma physics. The accomplishments described in this report have been in support of the programs of the Laser Plasma Branch (Code 6730) and other segments of the Plasma Physics Division at the Naval Research Laboratory (NRL) and cover the period 27 September 1993 to August 1, 1996. SAIC's efforts have been supported by sub-contracts or consulting agreements with Pulse Sciences, Inc., Clark Richardson, and Biskup Consulting Engineers, Pharos Technical Enterprises, Plex Corporation, Cornell University, Stevens Institute of Technology, the University of Connecticut, Plasma Materials and Technologies, Inc., and GaSonics International, Inc. In the following discussions section we will describe each of the topics investigated and the results obtained. Much of the research work has resulted in journal publications and NRL Memorandum Reports in which the investigation is described in detail. These reports are included as Appendices to this Final Report.

  2. NETL Extreme Drilling Laboratory Studies High Pressure High Temperature Drilling Phenomena

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lyons, K.D.; Honeygan, S.; Moroz, T.H.

    2008-12-01

    The U.S. Department of Energy's National Energy Technology Laboratory (NETL) established the Extreme Drilling Laboratory to engineer effective and efficient drilling technologies viable at depths greater than 20,000 ft. This paper details the challenges of ultradeep drilling, documents reports of decreased drilling rates as a result of increasing fluid pressure and temperature, and describes NETL's research and development activities. NETL is invested in laboratory-scale physical simulation. Its physical simulator will have capability of circulating drilling fluids at 30,000 psi and 480°F around a single drill cutter. This simulator is not yet operational; therefore, the results will be limited to themore » identification of leading hypotheses of drilling phenomena and NETL's test plans to validate or refute such theories. Of particular interest to the Extreme Drilling Laboratory's studies are the combinatorial effects of drilling fluid pressure, drilling fluid properties, rock properties, pore pressure, and drilling parameters, such as cutter rotational speed, weight on bit, and hydraulics associated with drilling fluid introduction to the rock-cutter interface. A detailed discussion of how each variable is controlled in a laboratory setting will be part of the conference paper and presentation.« less

  3. Laboratory Based Case Studies: Closer to the Real World

    ERIC Educational Resources Information Center

    Dinan, Frank J.

    2005-01-01

    Case-based laboratories offer students the chance to approximate real science. Based on interesting stories that pose problems requiring experimental solutions, they avoid the cookbook approach characteristic of traditional undergraduate laboratory instruction. Instead, case-based laboratories challenge students to develop, as much as possible,…

  4. Laboratory studies of in vivo fluorescence of phytoplankton

    NASA Technical Reports Server (NTRS)

    Brown, C. A., Jr.; Farmer, F. H.; Jarrett, O., Jr.; Staton, W. L.

    1978-01-01

    A lidar system is developed that uses four selected excitation wavelengths to induce chlorophyll 'a' fluorescence which is indicative of both the concentration and diversity of phytoplankton. The operating principles of the system and the results of measurements of phytoplankton fluorescence in a controlled laboratory environment are presented. A comparative study of results from lidar fluorosensor laboratory tank tests using representative species of phytoplankton in single and multispecies cultures from each of four color groups reveals that (1) there is good correlation between the fluorescence of chlorophyll 'a' remotely simulated and detected by the lidar system and in-situ measurements using four similar excitation wavelengths in a flow-through fluorometer; (2) good correlation exists between the total chlorophyll 'a' calculated from lidar-fluorosensor data and measurements obtained by the Strickland-Parsons method; and (3) the lidar fluorosensor can provide an index of population diversity.

  5. Studying Sexual Aggression: A Review of the Evolution and Validity of Laboratory Paradigms

    PubMed Central

    Davis, Kelly Cue; George, William H.; Nagayama Hall, Gordon C.; Parrott, Dominic J.; Tharp, Andra Teten; Stappenbeck, Cynthia A.

    2018-01-01

    Objective Researchers have endeavored for decades to develop and implement experimental assessments of sexual aggression and its precursors to capitalize on the many scientific advantages offered by laboratory experiments, such as rigorous control of key variables and identification of causal relationships. The purpose of this review is to provide an overview of and commentary on the evolution of these laboratory-based methods. Conclusions To date, two primary types of sexual aggression laboratory studies have been developed: those that involve behavioral analogues of sexual aggression and those that assess postulated precursors to sexually aggressive behavior. Although the study of sexual aggression in the laboratory is fraught with methodological challenges, validity concerns, and ethical considerations, advances in the field have resulted in greater methodological rigor, more precise dependent measures, and improved experimental validity, reliability, and realism. Because highly effective sexual aggression prevention strategies remain elusive, continued laboratory-based investigation of sexual aggression coupled with translation of critical findings to the development and modification of sexual aggression prevention programs remains an important task for the field. PMID:29675289

  6. Evaluation of Non-Laboratory and Laboratory Prediction Models for Current and Future Diabetes Mellitus: A Cross-Sectional and Retrospective Cohort Study

    PubMed Central

    Hahn, Seokyung; Moon, Min Kyong; Park, Kyong Soo; Cho, Young Min

    2016-01-01

    Background Various diabetes risk scores composed of non-laboratory parameters have been developed, but only a few studies performed cross-validation of these scores and a comparison with laboratory parameters. We evaluated the performance of diabetes risk scores composed of non-laboratory parameters, including a recently published Korean risk score (KRS), and compared them with laboratory parameters. Methods The data of 26,675 individuals who visited the Seoul National University Hospital Healthcare System Gangnam Center for a health screening program were reviewed for cross-sectional validation. The data of 3,029 individuals with a mean of 6.2 years of follow-up were reviewed for longitudinal validation. The KRS and 16 other risk scores were evaluated and compared with a laboratory prediction model developed by logistic regression analysis. Results For the screening of undiagnosed diabetes, the KRS exhibited a sensitivity of 81%, a specificity of 58%, and an area under the receiver operating characteristic curve (AROC) of 0.754. Other scores showed AROCs that ranged from 0.697 to 0.782. For the prediction of future diabetes, the KRS exhibited a sensitivity of 74%, a specificity of 54%, and an AROC of 0.696. Other scores had AROCs ranging from 0.630 to 0.721. The laboratory prediction model composed of fasting plasma glucose and hemoglobin A1c levels showed a significantly higher AROC (0.838, P < 0.001) than the KRS. The addition of the KRS to the laboratory prediction model increased the AROC (0.849, P = 0.016) without a significant improvement in the risk classification (net reclassification index: 4.6%, P = 0.264). Conclusions The non-laboratory risk scores, including KRS, are useful to estimate the risk of undiagnosed diabetes but are inferior to the laboratory parameters for predicting future diabetes. PMID:27214034

  7. Characterization and testing of amidoxime-based adsorbent materials to extract uranium from natural seawater

    DOE PAGES

    Kuo, Li-Jung; Janke, Christopher James; Wood, Jordana; ...

    2015-11-19

    Extraction of uranium (U) from seawater for use as a nuclear fuel is a significant challenge due to the low concentration of U in seawater (~3.3 ppb) and difficulties to selectively extract U from the background of major and trace elements in seawater. The Pacific Northwest National Laboratory (PNNL) s Marine Sciences Laboratory (MSL) has been serving as a marine test site for determining performance characteristics (adsorption capacity, adsorption kinetics, and selectivity) of novel amidoxime-based polymeric adsorbents developed at Oak Ridge National Laboratory (ORNL) under natural seawater exposure conditions. This report describes the performance of three formulations (38H, AF1, AI8)more » of amidoxime-based polymeric adsorbent produced at ORNL in MSL s ambient seawater testing facility. The adsorbents were produced in two forms, fibrous material (40-100 mg samples) and braided material (5-10 g samples), exposed to natural seawater using flow-through columns and recirculating flumes. All three formulations demonstrated high 56 day uranium adsorption capacity (>3 gU/kg adsorbent). The AF1 formulation had the best uranium adsorption performance, with 56-day capacity of 3.9 g U/kg adsorbent, saturation capacity of 5.4 g U/kg adsorbent, and ~25 days half-saturation time. The two exposure methods, flow-through columns and flumes were demonstrated to produce similar performance results, providing confidence that the test methods were reliable, that scaling up from 10 s of mg quantities of exposure in flow-through columns to gram quantities in flumes produced similar results, and that the manufacturing process produces a homogenous adsorbent. Adsorption kinetics appear to be element specific, with half-saturation times ranging from minutes for the major cations in seawater to 8-10weeks for V and Fe. Reducing the exposure time provides a potential pathway to improve the adsorption capacity of U by reducing the V/U ratio on the adsorbent.« less

  8. Characterization and Testing of Amidoxime-Based Adsorbent Materials to Extract Uranium from Natural Seawater

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kuo, Li-Jung; Janke, Christopher J.; Wood, Jordana R.

    Extraction of uranium (U) from seawater for use as a nuclear fuel is a significant challenge due to the low concentration of U in seawater (~3.3 ppb) and difficulties to selectively extract U from the background of major and trace elements in seawater. The Pacific Northwest National Laboratory (PNNL)’s Marine Sciences Laboratory (MSL) has been serving as a marine test site for determining performance characteristics (adsorption capacity, adsorption kinetics, and selectivity) of novel amidoxime-based polymeric adsorbents developed at Oak Ridge National Laboratory (ORNL) under natural seawater exposure conditions. This manuscript describes the performance of three formulations (38H, AF1, AI8) ofmore » amidoxime-based polymeric adsorbents produced at ORNL in MSL’s ambient seawater testing facility. The adsorbents were produced in two forms, fibrous material (40-100 mg samples) and braided material (5-10 g samples), and exposed to natural seawater using flow-through columns and recirculating flumes. All three formulations demonstrated high 56 day uranium adsorption capacity (>3 g U/kg adsorbent). The AF1 formulation had the best uranium adsorption performance, with a 56 day capacity of 3.9 g U/ kg adsorbent, a saturation capacity of 5.4 g U/kg adsorbent, and ~25 days half-saturation time. The two exposure methods, flowthrough columns and flumes, were demonstrated to produce similar performance results, providing confidence that the test methods were reliable, that scaling up from 10’s of mg quantities of exposure in flow-through columns to gram quantities in flumes produced similar results, and confirm that the manufacturing process produces a homogeneous adsorbent. Adsorption kinetics appear to be element specific, with half-saturation times ranging from minutes for the major cations in seawater, to 8-10 weeks for V and Fe. Reducing the exposure time provides a potential pathway to improve the adsorption capacity of U by reducing the V/U ratio on the adsorbent.« less

  9. Characterization and testing of amidoxime-based adsorbent materials to extract uranium from natural seawater

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kuo, Li-Jung; Janke, Christopher James; Wood, Jordana

    Extraction of uranium (U) from seawater for use as a nuclear fuel is a significant challenge due to the low concentration of U in seawater (~3.3 ppb) and difficulties to selectively extract U from the background of major and trace elements in seawater. The Pacific Northwest National Laboratory (PNNL) s Marine Sciences Laboratory (MSL) has been serving as a marine test site for determining performance characteristics (adsorption capacity, adsorption kinetics, and selectivity) of novel amidoxime-based polymeric adsorbents developed at Oak Ridge National Laboratory (ORNL) under natural seawater exposure conditions. This report describes the performance of three formulations (38H, AF1, AI8)more » of amidoxime-based polymeric adsorbent produced at ORNL in MSL s ambient seawater testing facility. The adsorbents were produced in two forms, fibrous material (40-100 mg samples) and braided material (5-10 g samples), exposed to natural seawater using flow-through columns and recirculating flumes. All three formulations demonstrated high 56 day uranium adsorption capacity (>3 gU/kg adsorbent). The AF1 formulation had the best uranium adsorption performance, with 56-day capacity of 3.9 g U/kg adsorbent, saturation capacity of 5.4 g U/kg adsorbent, and ~25 days half-saturation time. The two exposure methods, flow-through columns and flumes were demonstrated to produce similar performance results, providing confidence that the test methods were reliable, that scaling up from 10 s of mg quantities of exposure in flow-through columns to gram quantities in flumes produced similar results, and that the manufacturing process produces a homogenous adsorbent. Adsorption kinetics appear to be element specific, with half-saturation times ranging from minutes for the major cations in seawater to 8-10weeks for V and Fe. Reducing the exposure time provides a potential pathway to improve the adsorption capacity of U by reducing the V/U ratio on the adsorbent.« less

  10. Laboratory Experiments and Instrument Intercomparison Studies of Carbonaceous Aerosol Particles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Davidovits, Paul

    Aerosols containing black carbon (and some specific types of organic particulate matter) directly absorb incoming light, heating the atmosphere. In addition, all aerosol particles backscatter solar light, leading to a net-cooling effect. Indirect effects involve hydrophilic aerosols, which serve as cloud condensation nuclei (CCN) that affect cloud cover and cloud stability, impacting both atmospheric radiation balance and precipitation patterns. At night, all clouds produce local warming, but overall clouds exert a net-cooling effect on the Earth. The effect of aerosol radiative forcing on climate may be as large as that of the greenhouse gases, but predominantly opposite in sign andmore » much more uncertain. The uncertainties in the representation of aerosol interactions in climate models makes it problematic to use model projections to guide energy policy. The objective of our program is to reduce the uncertainties in the aerosol radiative forcing in the two areas highlighted in the ASR Science and Program Plan. That is, (1) addressing the direct effect by correlating particle chemistry and morphology with particle optical properties (i.e. absorption, scattering, extinction), and (2) addressing the indirect effect by correlating particle hygroscopicity and CCN activity with particle size, chemistry, and morphology. In this connection we are systematically studying particle formation, oxidation, and the effects of particle coating. The work is specifically focused on carbonaceous particles where the uncertainties in the climate relevant properties are the highest. The ongoing work consists of laboratory experiments and related instrument inter-comparison studies both coordinated with field and modeling studies, with the aim of providing reliable data to represent aerosol processes in climate models. The work is performed in the aerosol laboratory at Boston College. At the center of our laboratory setup are two main sources for the production of aerosol

  11. Change Analysis of Laser Scans of Laboratory Rock Slopes Subject to Wave Attack Testing

    NASA Astrophysics Data System (ADS)

    Shen, Y.; Lindenbergh, R.; Hofland, B.; Kramer, R.

    2017-09-01

    For better understanding how coastal structures with gentle slopes behave during high energy events, a wave attack experiment representing a storm of 3000 waves was performed in a flume facility. Two setups with different steepness of slope were compared under the same conditions. In order to quantify changes in the rock slopes after the wave attack, a terrestrial laser scanner was used to obtain 3D coordinates of the rock surface before and after each experiment. Next, through a series of processing steps, the point clouds were converted to a suitable 2D raster for change analysis. This allowed to estimate detailed and quantitative change information. The results indicate that the area around the artificial coast line, defined as the intersection between sloped surface and wave surface, is most strongly affected by wave attacks. As the distances from the sloped surface to the waves are shorter, changes for the mildly sloped surface, slope 1 (1 : 10), are distributed over a larger area compared to the changes for the more steeply sloped surface, slope 2 (1 : 5). The results of this experiment show that terrestrial laser scanning is an effective and feasible method for change analysis of rock slopes in a laboratory setting. Most striking results from a process point of view is that the transport direction of the rocks change between the two different slopes: from seaward transport for the steeper slope to landward transport for the milder slope.

  12. A study of 6S workplace improvement in Ergonomic Laboratory

    NASA Astrophysics Data System (ADS)

    Sari, AD; Suryoputro, MR; Rahmillah, FI

    2017-12-01

    This article discusses 6S implementation in Ergonomic Laboratory, Department of Industrial Engineering, Islamic University of Indonesia. This research is improvement project of 5S implementation in Ergonomic laboratory. Referring to the 5S implementation of the previous year, there have been improvements from environmental conditions or a more organized workplace however there is still a lack of safety aspects. There are several safeties problems such as equipment arrangement, potential hazards of room dividers that cause injury several times, placement of fire extinguisher, no evacuation path and assembly point in case of fire, as well as expired hydrant condition and lack of awareness of stakeholders related to safety. Therefore, this study aims to apply the 6S kaizen method to the Ergonomic laboratory to facilitate the work process, reduce waste, improve work safety and improve staff performance. Based on the score 6S assessment increased audit results by 32 points, before implementation is 75 point while after implementation is 107 point. This has implications for better use for mitigate people in laboratory area, save time when looking for tools and materials, safe workplace, as well as improving the culture and spirit of ‘6S’ on staff due to better and safetier working environment.

  13. Urine culture contamination: a College of American Pathologists Q-Probes study of 127 laboratories.

    PubMed

    Bekeris, Leonas G; Jones, Bruce Allen; Walsh, Molly K; Wagar, Elizabeth A

    2008-06-01

    While urine culture contamination may not be completely avoidable, some laboratories have lower contamination rates than others. A College of American Pathologists (CAP) 1998 Q-Probes study showed that many interventions commonly assumed to reduce contamination were not demonstrably effective. This article revisits the issue. To examine the frequency of urine culture contamination, review current laboratory practices in the collection of urine culture specimens, and determine practice characteristics that may be associated with the contamination rate. Laboratories participating in a CAP Q-Probes study were required to prospectively collect data on 120 consecutive urine culture specimens and provide information on the patient's demographics (age and sex), the location where the specimen was collected, how the specimen was handled, the number of isolates in quantities greater than or equal to 10,000 colony-forming units (CFU)/mL, and whether the laboratory considered the specimen to be contaminated. Specific inclusion and exclusion criteria were provided to the participants. Each laboratory completed a supplemental questionnaire that probed for specific laboratory urine culture collection practices. One hundred twenty-seven laboratories participated in the study. Results from a total of 14,739 urine specimens were received. For the purpose of this study, a urine specimen was determined to be contaminated if the culture yielded more than 2 isolates in quantities greater than or equal to 10,000 CFU/mL. Using these criteria the median institution had a contamination rate of 15.0%. Laboratories in the 10th percentile (low performance) had an average contamination rate of 41.7%, while laboratories in the 90th percentile had an average rate of 0.8%. The collection site had no influence on the contamination rate, but postcollection processing, especially refrigeration of the specimen, had a substantial effect. Providing instruction to patients produced a statistically

  14. Uprooting of flexible riparian vegetation: field and laboratory observations

    NASA Astrophysics Data System (ADS)

    Solari, L.; Calvani, G.; Francalanci, S.

    2017-12-01

    Vegetation is a key element in fluvial systems, controlling river corridor form and dynamics. Plants actively interact with fluvial processes; their aboveground biomass can affect the flow field and sediment transport and therefore river morphological evolution, whereas their belowground biomass modifies the hydraulic and mechanical properties of the substrate, and consequently the moisture regime and erodibility of the soil (Gurnell, 2014; Solari et al., 2015). Vegetation biomass can either increase over time or can die through the mechanism of uprooting. Despite its important implications in river morphodynamics, vegetation uprooting due to sediment transport during flood events have been poorly investigated (Edmaier et al., 2011). Most of previous research focused on the mechanism of root breakage and on measuring the vegetation resistance to uprooting in the vertical direction (Bywater-Reyes et al., 2015, among others). In this work, we focus on the uprooting of flexible juvenile seedlings vegetation due to flow and to bed erosion. First, we derive a physics-based model for the prediction of vegetation uprooting for given root geometry, soil strength characteristics, flow bed shear stress and bed erosion. The model is then tested in a laboratory flume using two different species of vegetation: Avena sativa and Salix purpurea. Various experiments were run considering increasing flow discharges and a quasi- parallel bed erosion. The vegetation model is then applied to a sediment bar in the Ombrone Pistoiese river where we observed the removal of Salix Purpurea during the flood of November 2016. We implemented a 2D hydraulic model to reconstruct the pattern of bed shear stresses on the bar and we compared the prediction of the vegetation model with the field surveys of Salix purpurea before and after the flood. Results suggest that juvenile seedlings can be easily removed by the flow provided sediment transport takes place.

  15. GeoBrain Computational Cyber-laboratory for Earth Science Studies

    NASA Astrophysics Data System (ADS)

    Deng, M.; di, L.

    2009-12-01

    Computational approaches (e.g., computer-based data visualization, analysis and modeling) are critical for conducting increasingly data-intensive Earth science (ES) studies to understand functions and changes of the Earth system. However, currently Earth scientists, educators, and students have met two major barriers that prevent them from being effectively using computational approaches in their learning, research and application activities. The two barriers are: 1) difficulties in finding, obtaining, and using multi-source ES data; and 2) lack of analytic functions and computing resources (e.g., analysis software, computing models, and high performance computing systems) to analyze the data. Taking advantages of recent advances in cyberinfrastructure, Web service, and geospatial interoperability technologies, GeoBrain, a project funded by NASA, has developed a prototype computational cyber-laboratory to effectively remove the two barriers. The cyber-laboratory makes ES data and computational resources at large organizations in distributed locations available to and easily usable by the Earth science community through 1) enabling seamless discovery, access and retrieval of distributed data, 2) federating and enhancing data discovery with a catalogue federation service and a semantically-augmented catalogue service, 3) customizing data access and retrieval at user request with interoperable, personalized, and on-demand data access and services, 4) automating or semi-automating multi-source geospatial data integration, 5) developing a large number of analytic functions as value-added, interoperable, and dynamically chainable geospatial Web services and deploying them in high-performance computing facilities, 6) enabling the online geospatial process modeling and execution, and 7) building a user-friendly extensible web portal for users to access the cyber-laboratory resources. Users can interactively discover the needed data and perform on-demand data analysis and

  16. Atmospheric cloud physics laboratory project study

    NASA Technical Reports Server (NTRS)

    Schultz, W. E.; Stephen, L. A.; Usher, L. H.

    1976-01-01

    Engineering studies were performed for the Zero-G Cloud Physics Experiment liquid cooling and air pressure control systems. A total of four concepts for the liquid cooling system was evaluated, two of which were found to closely approach the systems requirements. Thermal insulation requirements, system hardware, and control sensor locations were established. The reservoir sizes and initial temperatures were defined as well as system power requirements. In the study of the pressure control system, fluid analyses by the Atmospheric Cloud Physics Laboratory were performed to determine flow characteristics of various orifice sizes, vacuum pump adequacy, and control systems performance. System parameters predicted in these analyses as a function of time include the following for various orifice sizes: (1) chamber and vacuum pump mass flow rates, (2) the number of valve openings or closures, (3) the maximum cloud chamber pressure deviation from the allowable, and (4) cloud chamber and accumulator pressure.

  17. Laboratory studies of the interaction of ions with condensed gases: Planetary applications

    NASA Technical Reports Server (NTRS)

    Boring, J. W.; Johnson, R. E.

    1990-01-01

    The work described is concerned with laboratory studies of the processes that produce the ejection of molecules from the surfaces of condensed gas solids, the change in the chemistry of the surface materials, and the relationship of these results to processes occurring in the solar system. Included is a discussion of the experimental techniques employed in making these laboratory measurements.

  18. Comparison of microbiological diagnosis of urinary tract infection in young children by routine health service laboratories and a research laboratory: Diagnostic cohort study.

    PubMed

    Birnie, Kate; Hay, Alastair D; Wootton, Mandy; Howe, Robin; MacGowan, Alasdair; Whiting, Penny; Lawton, Michael; Delaney, Brendan; Downing, Harriet; Dudley, Jan; Hollingworth, William; Lisles, Catherine; Little, Paul; O'Brien, Kathryn; Pickles, Timothy; Rumsby, Kate; Thomas-Jones, Emma; Van der Voort, Judith; Waldron, Cherry-Ann; Harman, Kim; Hood, Kerenza; Butler, Christopher C; Sterne, Jonathan A C

    2017-01-01

    To compare the validity of diagnosis of urinary tract infection (UTI) through urine culture between samples processed in routine health service laboratories and those processed in a research laboratory. We conducted a prospective diagnostic cohort study in 4808 acutely ill children aged <5 years attending UK primary health care. UTI, defined as pure/predominant growth ≥105 CFU/mL of a uropathogen (the reference standard), was diagnosed at routine health service laboratories and a central research laboratory by culture of urine samples. We calculated areas under the receiver-operator curve (AUC) for UTI predicted by pre-specified symptoms, signs and dipstick test results (the "index test"), separately according to whether samples were obtained by clean catch or nappy (diaper) pads. 251 (5.2%) and 88 (1.8%) children were classified as UTI positive by health service and research laboratories respectively. Agreement between laboratories was moderate (kappa = 0.36; 95% confidence interval [CI] 0.29, 0.43), and better for clean catch (0.54; 0.45, 0.63) than nappy pad samples (0.20; 0.12, 0.28). In clean catch samples, the AUC was lower for health service laboratories (AUC = 0.75; 95% CI 0.69, 0.80) than the research laboratory (0.86; 0.79, 0.92). Values of AUC were lower in nappy pad samples (0.65 [0.61, 0.70] and 0.79 [0.70, 0.88] for health service and research laboratory positivity, respectively) than clean catch samples. The agreement of microbiological diagnosis of UTI comparing routine health service laboratories with a research laboratory was moderate for clean catch samples and poor for nappy pad samples and reliability is lower for nappy pad than for clean catch samples. Positive results from the research laboratory appear more likely to reflect real UTIs than those from routine health service laboratories, many of which (particularly from nappy pad samples) could be due to contamination. Health service laboratories should consider adopting procedures used in

  19. Comparison of microbiological diagnosis of urinary tract infection in young children by routine health service laboratories and a research laboratory: Diagnostic cohort study

    PubMed Central

    Birnie, Kate; Hay, Alastair D.; Wootton, Mandy; Howe, Robin; MacGowan, Alasdair; Whiting, Penny; Lawton, Michael; Delaney, Brendan; Downing, Harriet; Dudley, Jan; Hollingworth, William; Lisles, Catherine; Little, Paul; O’Brien, Kathryn; Pickles, Timothy; Rumsby, Kate; Thomas-Jones, Emma; Van der Voort, Judith; Waldron, Cherry-Ann; Harman, Kim; Hood, Kerenza; Butler, Christopher C.; Sterne, Jonathan A. C.

    2017-01-01

    Objectives To compare the validity of diagnosis of urinary tract infection (UTI) through urine culture between samples processed in routine health service laboratories and those processed in a research laboratory. Population and methods We conducted a prospective diagnostic cohort study in 4808 acutely ill children aged <5 years attending UK primary health care. UTI, defined as pure/predominant growth ≥105 CFU/mL of a uropathogen (the reference standard), was diagnosed at routine health service laboratories and a central research laboratory by culture of urine samples. We calculated areas under the receiver-operator curve (AUC) for UTI predicted by pre-specified symptoms, signs and dipstick test results (the “index test”), separately according to whether samples were obtained by clean catch or nappy (diaper) pads. Results 251 (5.2%) and 88 (1.8%) children were classified as UTI positive by health service and research laboratories respectively. Agreement between laboratories was moderate (kappa = 0.36; 95% confidence interval [CI] 0.29, 0.43), and better for clean catch (0.54; 0.45, 0.63) than nappy pad samples (0.20; 0.12, 0.28). In clean catch samples, the AUC was lower for health service laboratories (AUC = 0.75; 95% CI 0.69, 0.80) than the research laboratory (0.86; 0.79, 0.92). Values of AUC were lower in nappy pad samples (0.65 [0.61, 0.70] and 0.79 [0.70, 0.88] for health service and research laboratory positivity, respectively) than clean catch samples. Conclusions The agreement of microbiological diagnosis of UTI comparing routine health service laboratories with a research laboratory was moderate for clean catch samples and poor for nappy pad samples and reliability is lower for nappy pad than for clean catch samples. Positive results from the research laboratory appear more likely to reflect real UTIs than those from routine health service laboratories, many of which (particularly from nappy pad samples) could be due to contamination. Health service

  20. Productivity of Veterans Health Administration laboratories: a College of American Pathologists Laboratory Management Index Program (LMIP) study.

    PubMed

    Valenstein, Paul N; Wang, Edward; O'Donohue, Tom

    2003-12-01

    The Veterans Health Administration (VA) operates the largest integrated laboratory network in the United States. To assess whether the unique characteristics of VA laboratories impact efficiency of operations, we compared the productivity of VA and non-VA facilities. Financial and activity data were prospectively collected from 124 VA and 131 non-VA laboratories enrolled in the College of American Pathologists Laboratory Management Index Program (LMIP) during 2002. In addition, secular trends in 5 productivity ratios were calculated for VA and non-VA laboratories enrolled in LMIP from 1997 through 2002. Veterans Health Administration and non-VA facilities did not differ significantly in size. Inpatients accounted for a lower percentage of testing at VA facilities than non-VA facilities (21.7% vs 37.3%; P <.001). Technical staff at the median VA facility were paid more than at non-VA facilities (28.11/h dollars vs 22.60/h dollars, salaries plus benefits; P <.001), VA laboratories employed a smaller percentage of nontechnical staff (30.0% vs 41.9%; P <.001), and workers at VA laboratories worked less time per hour paid (85.5% vs 88.5%; P <.001). However, labor productivity was significantly higher at VA than at non-VA facilities (30 448 test results/total full-time equivalent (FTE)/y vs 19 260 results/total FTE; P <.001), resulting in lower labor expense per on-site test at VA sites than at non-VA sites (1.79 dollars/result vs 2.08 dollars/result; P <.001). Veterans Health Administration laboratories paid less per test for consumables (P =.003), depreciation, and maintenance than their non-VA counterparts (all P <.001), resulting in lower overall cost per on-site test result (2.64 dollars vs 3.40 dollars; P <.001). Cost per referred (sent-out) test did not differ significantly between the 2 groups. Analysis of 6-year trends showed significant increases in both VA (P <.001) and non-VA (P =.02) labor productivity (on-site tests/total FTE). Expenses at VA laboratories

  1. Expermental Investigation of Supercavitating Motion of Bodies

    DTIC Science & Technology

    2001-02-01

    information is ensured by studying of the model motion kinematics and photo- cinematography of its flow pictures. 4-9 Synchronization of work of the...on the depth 0.5 m along the flume axis. Photo- cinematography of the flow pictures was realized through the glass windows in walls of the flume and

  2. Virtual Laboratory "vs." Traditional Laboratory: Which Is More Effective for Teaching Electrochemistry?

    ERIC Educational Resources Information Center

    Hawkins, Ian; Phelps, Amy J.

    2013-01-01

    The use of virtual laboratories has become an increasing issue regarding science laboratories due to the increasing cost of hands-on laboratories, and the increase in distance education. Recent studies have looked at the use of virtual tools for laboratory to be used as supplements to the regular hands-on laboratories but many virtual tools have…

  3. Laboratory experiments in the study of the chemistry of the outer planets.

    PubMed

    Scattergood, T W

    1987-01-01

    The investigation of chemical evolution of bodies in our solar system has, in the past, included observations, theoretical modeling, and laboratory simulations. Of these programs, the last one has been the most criticized due to the inherent difficulties in accurately recreating alien environments in the laboratory. Processes such as wall reactions and changes in chemistry due to difficulties in achieving realistic conditions of temperature, pressure, composition, and energy flux may yield results which are not truly representative of the systems being modeled. However, many laboratory studies have been done which have yielded data useful in planetary science. Gross simulations of atmospheric chemistry have placed constraints on the nature of complex molecules expected in planetary atmospheres. More precise studies of specific chemical processes have provided information about the sources and properties of product gases and aerosols. Determinations of basic properties such as spectral features and reaction rate constants yield data useful in the interpretation of observations and in computational modeling. Alone, and in conjunction with modeling, laboratory experiments will continue to be used to further our understanding of the outer solar system, and some experiments that need to be done are listed.

  4. Laboratory Needs for Interstellar Ice Studies

    NASA Astrophysics Data System (ADS)

    Boogert, Abraham C. A.

    2012-05-01

    A large fraction of the molecules in dense interstellar and circumstellar environments is stored in icy grain mantles. The mantles are formed by a complex interplay between chemical and physical processes. Key questions on the accretion and desorption processes and the chemistry on the grain surfaces and within the icy mantles can only be answered by laboratory experiments. Recent infrared (2-30 micron) spectroscopic surveys of large samples of Young Stellar Objects (YSOs) and background stars tracing quiescent cloud material have shown that the ice band profiles and depths vary considerably as a function of environment. Using laboratory spectra in the identification process, it is clear that a rather complex mixture of simple species (CH3OH, CO2, H2O, CO) exists even in the quiescent cloud phase. Variations of the local physical conditions (CO freeze out) and time scales (CH3OH formation) appear to be key factors in the observed variations. Sublimation and thermal processing dominate as YSOs heat their environments. The identification of several ice absorption features is still disputed. I will outline laboratory work (e.g., on salts, PAHs, and aliphatic hydrocarbons) needed to further constrain the ice band identification as well as the thermal and chemical history of the carriers. Such experiments will also be essential to interpret future high spectral resolution SOFIA and JWST observations.

  5. Exploring the links between quality assurance and laboratory resources. An audit-based study.

    PubMed

    Singh, Navjeevan; Panwar, Aru; Masih, Vipin Fazal; Arora, Vinod K; Bhatia, Arati

    2003-01-01

    To investigate and rectify the problems related to Ziehl-Neelsen (Z-N) staining in a cytology laboratory in the context of quality assurance. An audit based quality assurance study of 1,421 patients with clinical diagnoses of tubercular lymphadenopathy who underwent fine needle aspiration cytology. Data from 8 months were audited (group 1). Laboratory practices related to selection of smears for Z-N staining were studied. A 2-step corrective measure based on results of the audit was introduced for 2 months (group 2). Results were subjected to statistical analysis using the chi 2 test. Of 1,172 patients in group 1,368 had diagnoses other than tuberculosis. Overall acid-fast bacillus (AFB) positivity was 42%. AFB positivity in 249 patients in group 2 was 89% (P < .0001). Several issues in the laboratory are linked to quality assurance. Solving everyday problems can have far-reaching benefits for the performance of laboratory personnel, resources and work flow.

  6. How do laboratory technicians perceive their role in the tuberculosis diagnostic process? A cross-sectional study among laboratory technicians in health centers of Central Java Province, Indonesia.

    PubMed

    Widjanarko, Bagoes; Widyastari, Dyah Anantalia; Martini, Martini; Ginandjar, Praba

    2016-01-01

    Detection of acid-fast bacilli in respiratory specimens serves as an initial pulmonary tuberculosis (TB) diagnosis. Laboratories are the essential and fundamental part of all health systems. This study aimed to describe how laboratory technicians perceived their own self and work. This included perceived self-efficacy, perceived role, perceived equipment availability, perceived procedures, perceived reward and job, and perceived benefit of health education, as well as level of knowledge and attitudes related to work performance of laboratory technicians. This was a cross-sectional quantitative study involving 120 laboratory technicians conducted in Central Java. Interviews and observation were conducted to measure performance and work-related variables. Among 120 laboratory technicians, 43.3% showed fairly good performance. They complied with 50%-75% of all procedures, including sputum collection, laboratory tools utilization, sputum smearing, staining, smear examination, grading of results, and universal precaution practice. Perceived role, perceived self-efficacy, and knowledge of laboratory procedures were significantly correlated to performance, besides education and years of working as a laboratory technician. Perceived equipment availability was also significantly correlated to performance after the education variable was controlled. Most of the laboratory technicians believed that they have an important role in TB patients' treatment and should display proper self-efficacy in performing laboratory activities. The result may serve as a basic consideration to develop a policy for enhancing motivation of laboratory technicians in order to improve the TB control program.

  7. How do laboratory technicians perceive their role in the tuberculosis diagnostic process? A cross-sectional study among laboratory technicians in health centers of Central Java Province, Indonesia

    PubMed Central

    Widjanarko, Bagoes; Widyastari, Dyah Anantalia; Martini, Martini; Ginandjar, Praba

    2016-01-01

    Purpose Detection of acid-fast bacilli in respiratory specimens serves as an initial pulmonary tuberculosis (TB) diagnosis. Laboratories are the essential and fundamental part of all health systems. This study aimed to describe how laboratory technicians perceived their own self and work. This included perceived self-efficacy, perceived role, perceived equipment availability, perceived procedures, perceived reward and job, and perceived benefit of health education, as well as level of knowledge and attitudes related to work performance of laboratory technicians. Methods This was a cross-sectional quantitative study involving 120 laboratory technicians conducted in Central Java. Interviews and observation were conducted to measure performance and work-related variables. Results Among 120 laboratory technicians, 43.3% showed fairly good performance. They complied with 50%–75% of all procedures, including sputum collection, laboratory tools utilization, sputum smearing, staining, smear examination, grading of results, and universal precaution practice. Perceived role, perceived self-efficacy, and knowledge of laboratory procedures were significantly correlated to performance, besides education and years of working as a laboratory technician. Perceived equipment availability was also significantly correlated to performance after the education variable was controlled. Conclusion Most of the laboratory technicians believed that they have an important role in TB patients’ treatment and should display proper self-efficacy in performing laboratory activities. The result may serve as a basic consideration to develop a policy for enhancing motivation of laboratory technicians in order to improve the TB control program. PMID:27660502

  8. Development of performance properties of ternary mixtures : laboratory study on concrete.

    DOT National Transportation Integrated Search

    2011-03-01

    This research project is a comprehensive study of how supplementary cementitious materials (SCMs) can be used to : improve the performance of concrete mixtures. This report summarizes the findings of the Laboratory Study on Concrete : phase of this w...

  9. Transferability and within- and between-laboratory reproducibilities of EpiSensA for predicting skin sensitization potential in vitro: A ring study in three laboratories.

    PubMed

    Mizumachi, Hideyuki; Sakuma, Megumi; Ikezumi, Mayu; Saito, Kazutoshi; Takeyoshi, Midori; Imai, Noriyasu; Okutomi, Hiroko; Umetsu, Asami; Motohashi, Hiroko; Watanabe, Mika; Miyazawa, Masaaki

    2018-05-03

    The epidermal sensitization assay (EpiSensA) is an in vitro skin sensitization test method based on gene expression of four markers related to the induction of skin sensitization; the assay uses commercially available reconstructed human epidermis. EpiSensA has exhibited an accuracy of 90% for 72 chemicals, including lipophilic chemicals and pre-/pro-haptens, when compared with the results of the murine local lymph node assay. In this work, a ring study was performed by one lead and two naive laboratories to evaluate the transferability, as well as within- and between-laboratory reproducibilities, of EpiSensA. Three non-coded chemicals (two lipophilic sensitizers and one non-sensitizer) were tested for the assessment of transferability and 10 coded chemicals (seven sensitizers and three non-sensitizers, including four lipophilic chemicals) were tested for the assessment of reproducibility. In the transferability phase, the non-coded chemicals (two sensitizers and one non-sensitizer) were correctly classified at the two naive laboratories, indicating that the EpiSensA protocol was transferred successfully. For the within-laboratory reproducibility, the data generated with three coded chemicals tested in three independent experiments in each laboratory gave consistent predictions within laboratories. For the between-laboratory reproducibility, 9 of the 10 coded chemicals tested once in each laboratory provided consistent predictions among the three laboratories. These results suggested that EpiSensA has good transferability, as well as within- and between-laboratory reproducibility. Copyright © 2018 John Wiley & Sons, Ltd.

  10. Laboratory studies of cometary ice analogues

    NASA Astrophysics Data System (ADS)

    Schmitt, B.; Espinasse, S.; Grim, R. J. A.; Greenberg, J. M.; Klinger, J.

    1989-12-01

    Laboratory studies were performed in order to simulate the physico-chemical processes that are likely to occur in the near surface layers of short and intermediate period comets. Pure H2O ice as well as CO:H2O, CO2:H2O, CH4:H2O, CO:CO2:H2O, and NH3:H2O ice mixtures were studied in the temperature range between 10 and 180 K. The evolution of the composition of ice mixtures, the crystallization of H2O ice as well as the formation and decompostion of clathrate hydrate by different processes were studied as a function of temperature and time. Using the results together with numerical modeling, predictions are made about the survival of amorphous ice, CO, CO2, CH4, and NH3 in the near surface layers of short period comets. The likeliness of finding clathrate and molecular hydrates is discussed. It is proposed that the analytical methods developed here could be fruitfully adapted to the analysis of returned comet samples.

  11. A Feasibility Study for Mobile Marketing and Distribution Occupational Laboratories in North Dakota.

    ERIC Educational Resources Information Center

    Kohns, Donald P.

    A study determined the feasibility of a mobile laboratory for marketing and distribution in North Dakota. It attempted to answer four questions: (1) What types of staffing, equipment, curriculum, and delivery systems are presently being utilized in mobile laboratories throughout the nation? (2) What significant information obtained from mobile…

  12. Turbulent Intensities and Velocity Spectra for Bare and Forested Gentle Hills: Flume Experiments

    NASA Astrophysics Data System (ADS)

    Poggi, Davide; Katul, Gabriel G.

    2008-10-01

    To investigate how velocity variances and spectra are modified by the simultaneous action of topography and canopy, two flume experiments were carried out on a train of gentle cosine hills differing in surface cover. The first experiment was conducted above a bare surface while the second experiment was conducted within and above a densely arrayed rod canopy. The velocity variances and spectra from these two experiments were compared in the middle, inner, and near-surface layers. In the middle layer, and for the canopy surface, longitudinal and vertical velocity variances ({σ_u^2,σ_w^2}) were in phase with the hill-induced spatial mean velocity perturbation (Δ u) around the so-called background state (taken here as the longitudinal mean at a given height) as predicted by rapid distortion theory (RDT). However, for the bare surface case, {σ_u^2 } and {σ_w^2 } remained out of phase with Δ u by about L/2, where L is the hill half-length. In the canopy layer, wake production was a significant source of turbulent energy for {σ_w^2 } , and its action was to re-align velocity variances with Δ u in those layers, a mechanism completely absent for the bare surface case. Such a lower ‘boundary condition’ resulted in longitudinal variations of {σ_w^2} to be nearly in phase with Δ u above the canopy surface. In the inner and middle layers, the spectral distortions by the hill remained significant for the background state of the bare surface case but not for the canopy surface case. In particular, in the inner and middle layers of the bare surface case, the effective exponents derived from the locally measured power spectra diverged from their expected - 5/3 value for inertial subrange scales. These departures spatially correlated with the hill surface. However, for the canopy surface case, the spectral exponents were near - 5/3 above the canopy though the minor differences from - 5/3 were also correlated with the hill surface. Inside the canopy, wake production

  13. Sediment laboratory quality-assurance project: studies of methods and materials

    USGS Publications Warehouse

    Gordon, J.D.; Newland, C.A.; Gray, J.R.

    2001-01-01

    In August 1996 the U.S. Geological Survey initiated the Sediment Laboratory Quality-Assurance project. The Sediment Laboratory Quality Assurance project is part of the National Sediment Laboratory Quality-Assurance program. This paper addresses the fmdings of the sand/fme separation analysis completed for the single-blind reference sediment-sample project and differences in reported results between two different analytical procedures. From the results it is evident that an incomplete separation of fme- and sand-size material commonly occurs resulting in the classification of some of the fme-size material as sand-size material. Electron microscopy analysis supported the hypothesis that the negative bias for fme-size material and the positive bias for sand-size material is largely due to aggregation of some of the fine-size material into sand-size particles and adherence of fine-size material to the sand-size grains. Electron microscopy analysis showed that preserved river water, which was low in dissolved solids, specific conductance, and neutral pH, showed less aggregation and adhesion than preserved river water that was higher in dissolved solids and specific conductance with a basic pH. Bacteria were also found growing in the matrix, which may enhance fme-size material aggregation through their adhesive properties. Differences between sediment-analysis methods were also investigated as pan of this study. Suspended-sediment concentration results obtained from one participating laboratory that used a total-suspended solids (TSS) method had greater variability and larger negative biases than results obtained when this laboratory used a suspended-sediment concentration method. When TSS methods were used to analyze the reference samples, the median suspended sediment concentration percent difference was -18.04 percent. When the laboratory used a suspended-sediment concentration method, the median suspended-sediment concentration percent difference was -2

  14. Bedform migration in steep channels: from local avalanches to large scale changes

    NASA Astrophysics Data System (ADS)

    Mettra, F.; Heyman, J.; Ancey, C.

    2013-12-01

    Many studies have emphasized the strength of bedload transport fluctuations in steep streams, especially at low and intermediate transport conditions (relative to the threshold of incipient motion). The origins of these fluctuations, which appear on a wide range of time scales, are still not well understood. In this study, we present the data obtained from a 2D idealized laboratory experiment with the objective of simultaneously recording the channel bed evolution and bedload transport rate at a high temporal resolution. A 3-m long by 8-cm wide transparent flume filled with well-sorted natural gravel (d50=6.5 mm) was used. An efficient technique using accelerometers has been developed to record the arrival time of every particle at the outlet of the flume for long experimental durations (up to a few days). In addition, bed elevation was monitored using cameras filming from the side of the channel, allowing the observation of global aggradation/degradation as well as bedform migration. The experimental parameters were the water discharge, the flume inclination (from 2° to 5°) and the constant feeding rate of sediments. Large-scale bed evolution showed successive aggradation and rapid degradation periods. Indeed, the measured global channel slope, i.e. mean slope over the flume length, fluctuated continuously within a range sometimes wider than 1° (experimental parameters were constant over the entire run). The analysis of these fluctuations provides evidence that steep channels behave like metastable systems, similarly to grain piles. The metastable effects increased for steeper channels and lower transport conditions. In this measurement campaign, we mainly observed upstream-migrating antidunes. For each run, various antidune heights and celerities were measured. On average, the mean antidune migration rate increased with decreasing channel slope and increasing sediment feeding rate. Relatively rare tall and fast-moving antidunes appeared more frequently at high

  15. [Comparability study of analytical results between a group of clinical laboratories].

    PubMed

    Alsius-Serra, A; Ballbé-Anglada, M; López-Yeste, M L; Buxeda-Figuerola, M; Guillén-Campuzano, E; Juan-Pereira, L; Colomé-Mallolas, C; Caballé-Martín, I

    2015-01-01

    To describe the study of the comparability of the measurements levels of biological tests processed in biochemistry in Catlab's 4 laboratories. Quality requirements, coefficients of variation and total error (CV% and TE %) were established. Controls were verified with the precision requirements (CV%) in each test and each individual laboratory analyser. Fresh serum samples were used for the comparability study. The differences were analysed using a Microsoft Access® application that produces modified Bland-Altman plots. The comparison of 32 biological parameters that are performed in more than one laboratory and/or analyser generated 306 Bland-Altman graphs. Of these, 101 (33.1%) fell within the accepted range of values based on biological variability, and 205 (66.9%) required revision. Data were re-analysed based on consensus minimum specifications for analytical quality (consensus of the Asociación Española de Farmacéuticos Analistas (AEFA), the Sociedad Española de Bioquímica Clínica y Patología Molecular (SEQC), the Asociación Española de Biopatología Médica (AEBM) and the Sociedad Española de Hematología y Hemoterapia (SEHH), October 2013). With the new specifications, 170 comparisons (56%) fitted the requirements and 136 (44%) required additional review. Taking into account the number of points that exceeded the requirement, random errors, range of results in which discrepancies were detected, and range of clinical decision, it was shown that the 44% that required review were acceptable, and the 32 tests were comparable in all laboratories and analysers. The analysis of the results showed that the consensus requirements of the 4 scientific societies were met. However, each laboratory should aim to meet stricter criteria for total error. Copyright © 2015 SECA. Published by Elsevier Espana. All rights reserved.

  16. STORM-SEWER FLOW MEASUREMENT AND RECORDING SYSTEM.

    USGS Publications Warehouse

    Kilpatrick, Frederick A.; Kaehrle, William R.

    1986-01-01

    A comprehensive study and development of instruments and techniques for measuring all components of flow in a storm-sewer drainage system were undertaken by the U. S. Geological Survey under the sponsorship of FHWA. The study involved laboratory and field calibration and testing of measuring flumes, pipe insert meters, weirs, and electromagnetic velocity meters as well as the development and calibration of pneumatic bubbler and pressure transducer head-measuring systems. Tracer dilution and acoustic-flowmeter measurements were used in field verification tests. A single micrologger was used to record data from all the instruments and also to activate on command the electromagnetic velocity meter and tracer dilution systems.

  17. Laboratory studies with the systemic trichononacide, metronidazole

    PubMed Central

    Jennison, R. F.; Stenton, P.; Watt, Leslie

    1961-01-01

    Laboratory studies with the trichomonacidal agent, metronidazole, show that 66 strains of T. vaginalis were killed in three days by concentrations of 0·0625 μg./ml. to 1 μg./ml. Estimations of serum and urine levels in nine volunteers, the serum levels in 31 women, and the urine levels in 33 women show that metronidazole is rapidly absorbed and excreted in high concentration in the urine. Development of resistance to metronidazole by T. vaginalis has not been demonstrated either in vivo or in vitro. No toxic effect was demonstrated in the blood, liver, or kidney. PMID:13789871

  18. The case for investigating social context in laboratory studies of smoking.

    PubMed

    Dimoff, John D; Sayette, Michael A

    2017-03-01

    With increasing frequency, addiction is conceived of as a brain disease, and such accounts seem especially pertinent with regard to the rapid delivery of nicotine to the brain via cigarette smoke. Moreover, drug administration trials (cigarette puffs) suggest that the behavior of smoking becomes automatized, with individuals developing prototypical approaches to smoking a cigarette. Compared with presumably more social activities, such as drinking alcohol, there may be little opportunity for social processes to influence smoking behavior. However, survey research examining smoking motivation often reveals a broadly defined 'social' factor and field research suggests that social context does influence smoking. We posit that laboratory smoking research has largely ignored social contextual factors that may help to understand better the precise mechanisms underlying smoking behavior and smoking motivation. We reviewed laboratory studies examining the effect of social context (operationalized as modeling) on smoking behavior. Studies were identified by searching PsychInfo and Medline using the following keywords: smoking, nicotine, tobacco, cigarette, consumption, topography, puff, smoking behavior, cigarettes smoked, modeling, imitation, social context, social influence and peer pressure. The reference and citation lists of these studies were then searched to identify additional studies. Few laboratory smoking studies target social context. Those few studies indicate that smoking behavior can be influenced by the presence of others. There is also some evidence that social context influences the effects of smoking as well as processes related to self-perception and self-regulation that reinforce smoking and hamper smoking cessation efforts. © 2016 Society for the Study of Addiction.

  19. Bed structure and bedload transport: Sediment grain reorientation in response to high and low flows in an experimental flume

    NASA Astrophysics Data System (ADS)

    Gurer, M.; Sullivan, S.; Masteller, C.

    2016-12-01

    Bedload is a regime of sediment transport that occurs when particles roll, hop, or bounce downstream. This mode of transport represents an important portion of the sediment load in a gravel river. Despite numerous studies focused on bedload transport, it still remains difficult to predict accurately due to the complex arrangement of riverbed particles. The formation of gravel clusters, stones being imbricated, or streamlined, and other interlocked arrangements, as well as grains armoring the bed, all tend to stabilize gravel channels and decrease bed mobility. Typically, the development of bed structure usually occurs as sediment moves downstream. However, it is unclear that gravel bed structure can be developed during weaker flows that do not generate significant sediment transport. We examine how individual sediment grains reorient themselves during low flow conditions, in the absence of sediment transport, and during high flow conditions, as bedload transport occurs. We then perform flume experiments where we expose a gravel bed to varying durations of low flow and raise the water level, simulating a flood and transporting sediment. We also compare the long-axis orientations of grains before and after each low flow period and transport. We find that sediment grains reorient themselves differently during low and high flows. During low flow, grains appear to reorient themselves with the long-axes towards cross-stream direction, or perpendicular to the flow, with longer duration flows resulting in more pronounced cross-stream orientation. During high flow, grains orient themselves with their long-axes facing downstream or parallel to the flow, similar to imbricated grains observed in the sedimentary record. Further, when transport occurs, we find that median grain orientation is strongly correlated with bedload transport rates (R^2 = 0.98). We also observe that median grain orientations more perpendicular to downstream flow result in reduced transport rates. This

  20. Detection of Cryptosporidium and Giardia in clinical laboratories in Europe--a comparative study.

    PubMed

    Manser, M; Granlund, M; Edwards, H; Saez, A; Petersen, E; Evengard, B; Chiodini, P

    2014-01-01

    To determine the routine diagnostic methods used and compare the performance in detection of oocysts of Cryptosporidium species and cysts of Giardia intestinalis in faecal samples by European specialist parasitology laboratories and European clinical laboratories. Two sets of seven formalin-preserved faecal samples, one containing cysts of Giardia intestinalis and the other, containing oocysts of Cryptosporidium, were sent to 18 laboratories. Participants were asked to examine the specimens using their routine protocol for detecting these parasites and state the method(s) used. Eighteen laboratories answered the questionnaire. For detection of Giardia, 16 of them used sedimentation/concentration followed by light microscopy. Using this technique the lower limit of detection of Giardia was 17.2 cysts/mL of faeces in the best performing laboratories. Only three of 16 laboratories used fluorescent-conjugated antibody-based microscopy. For detection of Cryptosporidium acid-fast staining was used by 14 of the 17 laboratories that examined the samples. With this technique the lower limit of detection was 976 oocysts/mL of faeces. Fluorescent-conjugated antibody-based microscopy was used by only five of the 17 laboratories. There was variation in the lower limit of detection of cysts of Giardia and oocysts of Cryptosporidium between laboratories using the same basic microscopic methods. Fluorescent-conjugated antibody-based microscopy was not superior to light microscopy under the conditions of this study. There is a need for a larger-scale multi-site comparison of the methods used for the diagnosis of these parasites and the development of a Europe-wide laboratory protocol based upon its findings. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

  1. Laboratory Study of Wave Generation Near Dipolarization Fronts

    NASA Astrophysics Data System (ADS)

    Tejero, E. M.; Enloe, C. L.; Amatucci, B.; Crabtree, C. E.; Ganguli, G.; Malaspina, D.

    2017-12-01

    Experiments conducted in the Space Physics Simulation Chamber at the Naval Research Laboratory (NRL) create plasma equilibria that replicate those found in dipolarization fronts. These experiments were designed to study the dynamics of boundary layers, such as dipolarization fronts, and it was found that there are instabilities generated by highly inhomogeneous plasma flows. It has previously been shown that these highly inhomogeneous flows can generate waves in the lower hybrid frequency range. Analysis of satellite observations indicate that the sheared flows are a plausible explanation for the observed lower hybrid waves at dipolarization fronts since they can generate longer wavelengths compared to the electron gyroradius, which is consistent with observations. Recent experiments at NRL have demonstrated that these flows can also generate electromagnetic waves in the whistler band. These waves are large amplitude, bursty waves that exhibit frequency chirps similar to whistler mode chorus. Recent results from these experiments and comparisons to in situ observations will be presented. * Work supported by the Naval Research Laboratory Base Program and NASA Grant No. NNH17AE70I.

  2. An experimental study of subaqueous slipface deposition.

    USGS Publications Warehouse

    Hunter, R.E.; Kocurek, G.

    1986-01-01

    A flume study indicates that grainflow on slipfaces accounts for most cross-strata formed in unidirectional, shallow-water flows. The slipfaces studied were on small megaripples and delta-like steps (0.06-0.28 m high). During intermittent avalanching, at relatively low flow velocities, periods between avalanches were marked by grainfall onto the slipface, the intensity of which was greatest near the brink of the slipface and increased with current velocity. The lee eddy proved very significant in slipface processes by redistributing grainfall sediments and both promoting and impeding grainflow. -from Authors

  3. Vertical Transport of Sediment from Muddy Buoyant River Plumes in the Presence of Different Modes of Interfacial Instabilities

    NASA Astrophysics Data System (ADS)

    Strom, K.; Rouhnia, M.

    2016-12-01

    Previous studies have suggested that sedimentation from buoyant, muddy plumes lofting over clear saltwater can take place at rates higher than that expected from individual particle settling (i.e., CWs). Two potential drivers of enhanced sedimentation are flocculation and interfacial instabilities. We experimentally measured the sediment fluxes from each of these processes using two sets of laboratory experiments that investigate two different modes of instability, one driven by sediment settling and one driven by fluid shear. The settling-driven and shear-driven instability experiments were carried out in a stagnant stratification tank and a stratification flume respectively. In both sets, continuous interface monitoring and concentration measurements were made to observe developments of instabilities and their effects on the removal of sediment. Floc size was measured during the experiments using a floc camera and image analysis routines. This presentation will provide an overview of the stagnant tank experiments, but will focus on results from the stratified flume experiments and an analysis that attempts to synthesizes the results from the entirety of the study. The results from the stratified flume experiments show that under shear instabilities, the effective settling velocity is greater than the floc settling velocity, and that the rate increases with plume velocity and interface mixing. The difference between effective and floc settling velocity was denoted as the shear-induced settling velocity. This rate was found to be a strong function of the Richardson number, and was attributed to mixing processes at the interface. Conceptual and empirical analysis shows that the shear-induced settling velocity is proportional to URi-2. The resulting effective settling velocity models developed from these experiments are then used to examine the rates and potential locations of operations of these mechanism over the length of a river mouth plume.

  4. Influence of anomalous temperature dependence of water density on convection at lateral heating

    NASA Astrophysics Data System (ADS)

    Bukreev, V. I.; Gusev, A. V.

    2012-12-01

    The article provides results of experimental investigation of a fresh water motion in a flume with limited dimensions at lateral heating. The initial water temperature in the flume ranged from 0 to 22 °C. It is shown that there are qualitative changes of the motion picture in the vicinity of initial temperature in the flume equal to the one at which water has maximal density (approximately 4 °C). At an initial temperature in the flume exceeding or equal to 4 °C, the heated water propagates in the form of a relatively thin surface jet, and at jet reflection from the flume end walls the heated water is accumulated only in the upper layer. When the initial temperature in the flume is below 4 °C the convective instability develops. A part of the heated water sinks to the bottom. The paper provides respective illustrations and quantitative data on the distribution of temperature and velocity.

  5. Laboratory study of spectral waves over a muddy bottom

    NASA Astrophysics Data System (ADS)

    Maxeiner, E.; Dalrymple, R. A.

    2010-12-01

    The attenuation of water waves propagating over a muddy ocean floor has been studied extensively both analytically and experimentally over the past 30 years. Possible mechanisms for this include surface wave interactions with the bottom, surface wave interactions with waves formed at the water/mud interface (lutocline) and shear instability at the water/mud interface. Typically these studies have focused on monochromatic waves. Observations of wave attenuation in the field, however, are subject to a spectrum of wave frequencies and sizes. A few field studies (Sheremet and Stone, 2003; Elgar and Raubenheimer, 2008) have explored the possible effects that a wide spectrum of wave frequencies may have on wave damping mechanisms. In this study, the wave attenuation exhibited by a sea spectrum over a muddy bottom is studied experimentally in a laboratory for the first time. Using an 18 m-long wave tank at the Coastal Engineering Laboratory at Johns Hopkins University, a piston-style wave maker is used to create both monochromatic and spectral waves. A 10 m-long section of the tank floor incorporates a recessed layer of kaolinite clay which subsequently mixes with the overlying water in the presence of waves. Testing consists of three phases. First, a series of monochromatic wave trains are produced over a range of wave frequencies and in a range of water depths to assess the damping behavior with respect to a variety of parameters such as wave frequency, wave height and water depth. Damping is assessed by comparing wave height at various longitudinal locations in the tank. Second, “wave beats” are created by superimposing waves of two frequencies to create a longer envelope. Third, the wave maker is used to generate a representative random sea condition, based on the Pierson-Moskowitz sea spectrum. For this type of testing, damping is assessed by measuring wave energy flux over a period of time at various longitudinal locations in the tank. Spectral analysis is also

  6. Factors controlling the size and shape of stream channels in coarse noncohesive sands

    USGS Publications Warehouse

    Wolman, M. Gordon; Brush, Lucien M.

    1961-01-01

    The size and shape of equilibrium channels in uniform, noncohesive sands, 0.67 mm and 2.0 mm in diameter, were studied experimentally in a laboratory flume 52 feet long in which discharge, slope, sediment load, and bed and bank material could be varied independently. For each run a straight trapezoidal channel was molded in the sand and the flume set at a predetermined slope. Introduction of the discharge was accompanied by widening and aggradation until a stable channel was established. By definition a stable equilibrium existed when channel width, water surface slope, and rate of transport became constant. The duration of individual runs ranged from 2 to 52 hours depending upon the time required for establishing equilibrium. Stability of the banks determined channel shape. In the 2.0 mm sand at a given slope and discharge, only one depth was stable. At this depth the flow was just competent to move particles along the bed of the channel. An increase in discharge produced a wider channel of the same depth and thus transport per unit width remained at a minimum. Channels in the 0.67 mm sand were somewhat more stable and permitted a 1.5 fold increase in depth above that required to start movement of the bed material. An increased transport was associated with the increase in depth. The rate of transport is adequately described in terms of the total shear or in terms of the difference between the total shear and the critical shear required to begin movement. In these experiments the finer, or 0.67 mm, sand, began to move along the bed of the channel at a constant shear stress. Incipient movement of the coarser, or 2.0 mm, sand, varied with the shear stress as well as the mean velocity. At the initiation of movement a lower shear was associated with a higher velocity and vice versa. Anabranches of braided rivers and some natural river channels formed in relatively noncohesive materials resemble the essential characteristics of the flume channels. For a given slope and

  7. Variances and uncertainties of the sample laboratory-to-laboratory variance (S(L)2) and standard deviation (S(L)) associated with an interlaboratory study.

    PubMed

    McClure, Foster D; Lee, Jung K

    2012-01-01

    The validation process for an analytical method usually employs an interlaboratory study conducted as a balanced completely randomized model involving a specified number of randomly chosen laboratories, each analyzing a specified number of randomly allocated replicates. For such studies, formulas to obtain approximate unbiased estimates of the variance and uncertainty of the sample laboratory-to-laboratory (lab-to-lab) STD (S(L)) have been developed primarily to account for the uncertainty of S(L) when there is a need to develop an uncertainty budget that includes the uncertainty of S(L). For the sake of completeness on this topic, formulas to estimate the variance and uncertainty of the sample lab-to-lab variance (S(L)2) were also developed. In some cases, it was necessary to derive the formulas based on an approximate distribution for S(L)2.

  8. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... specimen in a manner that precludes error in the recording and storage of data. (d) Records of gross... that specimen histopathologically. (e) All data generated during the conduct of a nonclinical laboratory study, except those that are generated by automated data collection systems, shall be recorded...

  9. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... specimen in a manner that precludes error in the recording and storage of data. (d) Records of gross... that specimen histopathologically. (e) All data generated during the conduct of a nonclinical laboratory study, except those that are generated by automated data collection systems, shall be recorded...

  10. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... specimen in a manner that precludes error in the recording and storage of data. (d) Records of gross... that specimen histopathologically. (e) All data generated during the conduct of a nonclinical laboratory study, except those that are generated by automated data collection systems, shall be recorded...

  11. Interactions Between Hydropeaking and Thermopeaking Waves and Their Effect on the Benthic Community in Flume Simulations

    NASA Astrophysics Data System (ADS)

    Bruno, M.; Carolli, M.; Maiolini, B.; Siviglia, A.; Zolezzi, G.

    2013-12-01

    induced responses on benthic macroinvertebrates, i.e., the active (behavioral) and passive (catastrophic) drift. Although the achieved changes in temperature were within the tolerability range for benthic invertebrates, their drift propensity increased threefold and fivefold, and twofold and fourfold in the two cold and two warm thermopeaking experiments, respectively. Drift was probably behavioral, given the immediate responses of invertebrates which seek habitat patches downstream, that are within their temperature tolerance and/or preference levels. Catastrophic and behavioral drift can occur as distinct events in hydropeaking-impacted streams, thus we analyzed the effects of a hydropeaking wave followed by a thermopeaking wave in the same flume. We observed that the slight but abrupt increase in discharge caused an increase in drift of elevenfold the basedrift, but the abrupt decrease in temperature caused a stronger response, of thirty-ninefold the basedrift. Our experimental results suggest that effects of thermopeaking are mixed and synergic with those due to hydropeaking, and in the long-term may alter the longitudinal distribution of benthic communities. Such complex responses should be taken into account in simulation studies, in modelling of aquatic ecosystems and in proposing remediation strategies to hydropeaking-impacted rivers.

  12. Safety in laboratories: Indian scenario.

    PubMed

    Mustafa, Ajaz; Farooq, A Jan; Qadri, Gj; S A, Tabish

    2008-07-01

    Health and safety in clinical laboratories is becoming an increasingly important subject as a result of emergence of highly infectious diseases such as Hepatitis and HIV. A cross sectional study was carried out to study the safety measures being adopted in clinical laboratories of India. Heads of laboratories of teaching hospitals of India were subjected to a standardized, pretested questionnaire. Response rate was 44.8%. only 60% of laboratories had person in-charge of safety in laboratory. Seventy three percent of laboratories had safety education program regarding hazards. In 91% of laboratories staff is using protective clothing while working in laboratories. Hazardous material regulations are followed in 78% of laboratories. Regular health check ups are carried among laboratory staff in 43.4% of laboratories.Safety manual is available in 56.5% of laboratories. 73.9% of laboratories are equipped with fire extinguishers. Fume cupboards are provided in 34.7% of laboratories and they are regularly checked in 87.5% of these laboratories. In 78.26% of laboratories suitable measures are taken to minimize formation of aerosols.In 95.6% of laboratories waste is disposed off as per bio-medical waste management handling rules. Laboratory of one private medical college was accredited with NABL and safety parameters were better in that laboratory. Installing safety engineered devices apparently contributes to significant decrease in injuries in laboratories; laboratory safety has to be a part of overall quality assurance programme in hospitals. Accreditation has to be made necessary for all laboratories.

  13. A cross-laboratory preclinical study on the effectiveness of interleukin-1 receptor antagonist in stroke

    PubMed Central

    Maysami, Samaneh; Wong, Raymond; Pradillo, Jesus M; Denes, Adam; Dhungana, Hiramani; Malm, Tarja; Koistinaho, Jari; Orset, Cyrille; Rahman, Mahbubur; Rubio, Marina; Schwaninger, Markus; Vivien, Denis; Bath, Philip M; Rothwell, Nancy J

    2015-01-01

    Stroke represents a global challenge and is a leading cause of permanent disability worldwide. Despite much effort, translation of research findings to clinical benefit has not yet been successful. Failure of neuroprotection trials is considered, in part, due to the low quality of preclinical studies, low level of reproducibility across different laboratories and that stroke co-morbidities have not been fully considered in experimental models. More rigorous testing of new drug candidates in different experimental models of stroke and initiation of preclinical cross-laboratory studies have been suggested as ways to improve translation. However, to our knowledge, no drugs currently in clinical stroke trials have been investigated in preclinical cross-laboratory studies. The cytokine interleukin 1 is a key mediator of neuronal injury, and the naturally occurring interleukin 1 receptor antagonist has been reported as beneficial in experimental studies of stroke. In the present paper, we report on a preclinical cross-laboratory stroke trial designed to investigate the efficacy of interleukin 1 receptor antagonist in different research laboratories across Europe. Our results strongly support the therapeutic potential of interleukin 1 receptor antagonist in experimental stroke and provide further evidence that interleukin 1 receptor antagonist should be evaluated in more extensive clinical stroke trials. PMID:26661169

  14. Laboratory performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

    USGS Publications Warehouse

    Gordon, John D.; Newland, Carla A.; Gagliardi, Shane T.

    2000-01-01

    Analytical results from all sediment quality-control samples are compiled and statistically summarized by the USGS, Branch of Quality Systems, both on an intra- and interlaboratory basis. When evaluating these data, the reader needs to keep in mind that every measurement has an error component associated with it. It is premature to use the data from the first five SLQA studies to judge any of the laboratories as performing in an unacceptable manner. There were, however, some notable differences in the results for the 12 laboratories that participated in the five SLQA studies. For example, the overall median percent difference for suspended-sediment concentration on an individual laboratory basis ranged from –18.04 to –0.33 percent. Five of the 12 laboratories had an overall median percent difference for suspended-sediment concentration of –2.02 to –0.33 percent. There was less variability in the median difference for the measured fine-size material mass. The overall median percent difference for fine-size material mass ranged from –10.11 to –4.27 percent. Except for one laboratory, the median difference for fine-size material mass was within a fairly narrow range of –6.76 to –4.27 percent. The median percent difference for sand-size material mass differed among laboratories more than any other physical sediment property measured in the study. The overall median percent difference for the sand-size material mass ranged from –1.49 percent to 26.39 percent. Five of the nine laboratories that do sand/fine separations had overall median percent differences that ranged from –1.49 to 2.98 percent for sand-size material mass. Careful review of the data reveals that certain laboratories consistently produced data within statistical control limits for some or all of the physical sediment properties measured in this study, whereas other laboratories occasionally produced data that exceeded the control limits.

  15. Biofilm resilience to desiccation in groundwater aquifers: a laboratory and field study.

    PubMed

    Weaver, L; Webber, J B; Hickson, A C; Abraham, P M; Close, M E

    2015-05-01

    Groundwater is used as a precious resource for drinking water worldwide. Increasing anthropogenic activity is putting increasing pressure on groundwater resources. One impact of increased groundwater abstraction coupled with increasing dry weather events is the lowering of groundwater levels within aquifers. Biofilms within groundwater aquifers offer protection to the groundwater by removing contaminants entering the aquifer systems from land use activities. The study presented investigated the impact of desiccation events on the biofilms present in groundwater aquifers using field and laboratory experiments. In both field and laboratory experiments a reduction in enzyme activity (glucosidase, esterase and phosphatase) was seen during desiccation compared to wet controls. However, comparing all the data together no significant differences were seen between either wet or desiccated samples or between the start and end of the experiments. In both field and laboratory experiments enzyme activity recovered to start levels after return to wet conditions. The study shows that biofilms within groundwater systems are resilient and can withstand periods of desiccation (4 months). Copyright © 2014 Elsevier B.V. All rights reserved.

  16. A STUDY OF SMALL GROUP DYNAMICS AND PRODUCTIVITY IN THE BSCS LABORATORY BLOCK PROGRAM.

    ERIC Educational Resources Information Center

    HURD, PAUL DEHART; ROWE, MARY BUDD

    THE RELATIONSHIP BETWEEN SMALL GROUP COMPATIBILITY AND ACHIEVEMENT IN THE BIOLOGICAL SCIENCE CURRICULUM STUDY LABORATORY BLOCK PROGRAM WAS TESTED. STUDENTS IN 14 CLASSES FROM FOUR HIGH SCHOOLS WERE ASSIGNED TO FOUR-MEMBER LABORATORY GROUPS CLASSIFIED AS COMPATIBLE OR INCOMPATIBLE. GROUP CLASSIFICATION WAS VALIDATED BY OBSERVERS WHO WERE NOT AWARE…

  17. [Laboratory and clinical study of intravenous miconazole].

    PubMed

    Sawae, Y; Okada, K; Kumagai, Y

    1987-02-01

    Laboratory and clinical study was carried out on miconazole (MCZ), a new synthetic imidazole. The antifungal activity of MCZ was studied and expressed as MICs for clinical isolates. The drug proved to have the highest activity against Cryptococcus neoformans, with MICs of no more than 0.16 micrograms/ml for all isolates of this species. MICs of Torulopsis glabrata were 0.08-5 micrograms/ml for all isolates and those of Candida albicans and Candida tropicalis were 5-20 micrograms/ml for more than 90% of the isolates. Most of other strains were less than 10 micrograms/ml. When 3 healthy adult men were administered each with 200 mg of MCZ by intravenous drip infusion for 1.25 hours, the mean serum MCZ concentration was 1.39 micrograms/ml at the end of the infusion, then decreased rapidly to 0.49 microgram/ml in following 30 minutes, and then decreased gradually to 0.17 microgram/ml 6 hours later. The mean cumulative urinary excretion rate of the drug was as low as 3.0% at this stage. A total of 25 patients with ages of 30-78 years, comprising 17 men and 8 women, were treated with 200-1,800 mg of MCZ daily for 3-93 days. The clinical effectiveness was ascertained in 19 cases among the patients; 9 cases with candidiasis, 3 with cryptococcosis and 7 with aspergillosis. Clinical responses were excellent in 2, good in 9 and poor in 8 cases, and its efficacy rates was 58%. The efficacy rate of the combination therapy with other antifungal agents was 60% in comparison with 57% of MCZ alone. Adverse reactions to the drug such as nausea, vomiting and anorexia were observed in 3 cases (12%). Abnormal changes in laboratory parameters were also observed: 3 patients with elevations of GOT and GPT, and another with eosinophilia.

  18. [The external evaluation of study quality: the role in maintaining the reliability of laboratory information].

    PubMed

    Men'shikov, V V

    2013-08-01

    The external evaluation of quality of clinical laboratory examinations was gradually introduced in USSR medical laboratories since 1970s. In Russia, in the middle of 1990 a unified all-national system of external evaluation quality was organized known as the Federal center of external evaluation of quality at the basis of laboratory of the state research center of preventive medicine. The main positions of policy in this area were neatly formulated in the guidance documents of ministry of Health. Nowadays, the center of external evaluation of quality proposes 100 and more types of control studies and permanently extends their specter starting from interests of different disciplines of clinical medicine. The consistent participation of laboratories in the cycles of external evaluation of quality intrinsically promotes improvement of indicators of properness and precision of analysis results and increases reliability of laboratory information. However, a significant percentage of laboratories does not participate at all in external evaluation of quality or takes part in control process irregularly and in limited number of tests. The managers of a number of medical organizations disregard the application of the proposed possibilities to increase reliability of laboratory information and limit financing of studies in the field of quality control. The article proposes to adopt the national standard on the basis of ISO 17043 "Evaluation of compliance. The common requirements of professional competence testing".

  19. The effect of vegetation height and biomass on the sediment budget of a European saltmarsh

    NASA Astrophysics Data System (ADS)

    Reef, Ruth; Schuerch, Mark; Christie, Elizabeth K.; Möller, Iris; Spencer, Tom

    2018-03-01

    Sediment retention in saltmarshes is often attributed to the presence of vegetation, which enhances accretion by slowing water flow, reduces erosion by attenuating wave energy and increases surface stability through the presence of organic matter. Saltmarsh vegetation morphology varies considerably on a range of spatial and temporal scales, but the effect of different above ground morphologies on sediment retention is not well characterised. Understanding the biophysical interaction between the canopy and sediment trapping in situ is important for improving numerical shoreline models. In a novel field flume study, we measured the effect of vegetation height and biomass on sediment trapping using a mass balance approach. Suspended sediment profilers were placed at both openings of a field flume built across-shore on the seaward boundary of an intertidal saltmarsh in the Dengie Peninsula, UK. Sequential removal of plant material from within the flume resulted in incremental loss of vegetation height and biomass. The difference between the concentration of suspended sediment measured at each profiler was used to determine the sediment budget within the flume. Deposition of material on the plant/soil surfaces within the flume occurred during flood tides, while ebb flow resulted in erosion (to a lesser degree) from the flume area, with a positive sediment budget of on average 6.5 g m-2 tide-1 with no significant relationship between sediment trapping efficiency and canopy morphology. Deposition (and erosion) rates were positively correlated to maximum inundation depth. Our results suggest that during periods of calm conditions, changes to canopy morphology do not result in significant changes in sediment budgets in marshes.

  20. Seven Principles of Instructional Content Design for a Remote Laboratory: A Case Study on ERRL

    ERIC Educational Resources Information Center

    Cagiltay, N. E.; Aydin, E.; Aydin, C. C.; Kara, A.; Alexandru, M.

    2011-01-01

    This paper discusses the results of a study of the requirements for developing a remote radio frequency (RF) laboratory for electrical engineering students. It investigates students' preferred usage of the technical content of a state-of-the-art RF laboratory. The results of this study are compared to previous findings, which dealt with other user…

  1. Case study: improving efficiency in a large hospital laboratory.

    PubMed

    Bartel, Marilynn

    2004-01-01

    Saint Francis Health System (SFHS) consists of three hospitals and one clinic: Saint Francis Hospital (SFH); Broken Arrow Medical Center; Laureate Psychiatric Hospital; and Warren Clinic. SFHS has 670 physicians on staff and serves medical (oncology, orthopedic, neurology, and renal), surgical, cardiac, women and infant, pediatric, transplant, and trauma patients in Tulsa County, Oklahoma, which has a population of 660,000. SFH incorporates 706 staffed beds, including 126 pediatric beds and 119 critical care beds. Each year, the health system averages 38,000 admissions, 70,000 emergency department visits, 25,000 surgeries, and 3,500 births. Saint Francis Laboratory is located within the main hospital facility (SFH) and functions as a core lab for the health system. The lab also coordinates lab services with Saint Francis Heart Hospital, a physician-system joint venture. The Optimal Equipment Configuration (OEC) Project was designed by the Clinical Laboratory Services division of Premier, a group purchasing organization, with the goal of determining whether laboratories could improve efficiency and decrease unit cost by using a single-source vendor. Participants included seven business partners (Abbott, Bayer, Beckman/Coulter, Dade/Behring, J&J/ Ortho, Olympus, and Roche) and 21 laboratory sites (a small, mid-sized, and large site for each vendor). SFH laboratory staff embraced Premier's concept and viewed the OEC project as an opportunity to "energize" laboratory operations. SFH partnered with Abbott, their primary equipment vendor, for the project. Using resources and tools made available through the project, the laboratory was re-engineered to simplify workflow, increase productivity, and decrease costs by adding automation and changing to centralized specimen processing. Abbott and SFH shared a common vision for the project and enhanced their partnership through increased communication and problem solving. Abbott's area representatives provided for third

  2. Rainfall simulators - innovations seeking rainfall uniformity and automatic flow rate measurements

    NASA Astrophysics Data System (ADS)

    Bauer, Miroslav; Kavka, Petr; Strouhal, Luděk; Dostál, Tomáš; Krása, Josef

    2016-04-01

    single pressure operating mode, which is ensured by the pressure probe controlled electromagnetic valve. Previous experiments implied the need of automatic continuous measurements of selected variables. To this end the control unit was equipped with a datalogger. In a several seconds time step it collects the values of water pressure, nozzle-valves operation, control point rainfall intensity from a tipping bucket rain gauge, topsoil moisture from several Theta ML2x probes and most recently the plot outlet runoff rate. For a continuous runoff rate measurement a 0,4-foot HS-flume was constructed and equipped with S18U ultrasonic sensor. Assemble setting was optimised both in flow rate laboratory flume and in laboratory rainfall simulator. Namely the rating curves for particular flume bottom slopes were derived. Employment of the flume in the terrain is scheduled for the experimental season 2016, but laboratory results already show sufficient measurement accuracy and are promising in terms of experimental campaigns simplification. The abovementioned activities have been supported by the research grants SGS14/180/OHK1/3T/11, QJ1530181, QJ1520265 and QJ1330118.

  3. Field Research Studying Whales in an Undergraduate Animal Behavior Laboratory

    ERIC Educational Resources Information Center

    MacLaren, R. David; Schulte, Dianna; Kennedy, Jen

    2012-01-01

    This work describes a new field research laboratory in an undergraduate animal behavior course involving the study of whale behavior, ecology and conservation in partnership with a non-profit research organization--the Blue Ocean Society for Marine Conservation (BOS). The project involves two weeks of training and five weekend trips on whale watch…

  4. Partnering at the National Laboratories: Catalysis as a Case Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    JACKSON,NANCY B.

    1999-09-14

    The role of the national laboratories, particularly the defense program laboratories, since the end of the cold war, has been a topic of continuing debate. The relationship of national laboratories to industry spurred debate which ranged from designating the labs as instrumental to maintaining U.S. economic competitiveness to concern over the perception of corporate welfare to questions regarding the industrial globalization and the possibility of U.S. taxpayer dollars supporting foreign entities. Less debated, but equally important, has been the national laboratories' potential competition with academia for federal research dollars and discussions detailing the role of each in the national researchmore » enterprise.« less

  5. A SURVEY OF LABORATORY AND STATISTICAL ISSUES RELATED TO FARMWORKER EXPOSURE STUDIES

    EPA Science Inventory

    Developing internally valid, and perhaps generalizable, farmworker exposure studies is a complex process that involves many statistical and laboratory considerations. Statistics are an integral component of each study beginning with the design stage and continuing to the final da...

  6. Feasibility study of a zero-gravity (orbital) atmospheric cloud physics experiments laboratory

    NASA Technical Reports Server (NTRS)

    Hollinden, A. B.; Eaton, L. R.

    1972-01-01

    A feasibility and concepts study for a zero-gravity (orbital) atmospheric cloud physics experiment laboratory is discussed. The primary objective was to define a set of cloud physics experiments which will benefit from the near zero-gravity environment of an orbiting spacecraft, identify merits of this environment relative to those of groundbased laboratory facilities, and identify conceptual approaches for the accomplishment of the experiments in an orbiting spacecraft. Solicitation, classification and review of cloud physics experiments for which the advantages of a near zero-gravity environment are evident are described. Identification of experiments for potential early flight opportunities is provided. Several significant accomplishments achieved during the course of this study are presented.

  7. Cost-price estimation of clinical laboratory services based on activity-based costing: A case study from a developing country

    PubMed Central

    Mouseli, Ali; Barouni, Mohsen; Amiresmaili, Mohammadreza; Samiee, Siamak Mirab; Vali, Leila

    2017-01-01

    Background It is believed that laboratory tariffs in Iran don’t reflect the real costs. This might expose private laboratories at financial hardship. Activity Based Costing is widely used as a cost measurement instrument to more closely approximate the true cost of operations. Objective This study aimed to determine the real price of different clinical tests of a selected private clinical laboratory. Methods This study was a cross sectional study carried out in 2015. The study setting was the private laboratories in the city of Kerman, Iran. Of 629 tests in the tariff book of the laboratory (relative value), 188 tests were conducted in the laboratory that used Activity Based Costing (ABC) methodology to estimate cost-price. Analyzing and cost-price estimating of laboratory services were performed by MY ABCM software Version 5.0. Results In 2015, the total costs were $641,645. Direct and indirect costs were 78.3% and 21.7% respectively. Laboratory consumable costs by 37% and personnel costs by 36.3% had the largest share of the costing. Also, group of hormone tests cost the most $147,741 (23.03%), and other tests group cost the least $3,611 (0.56%). Also after calculating the cost of laboratory services, a comparison was made between the calculated price and the private sector’s tariffs in 2015. Conclusion This study showed that there was a difference between costs and tariffs in the private laboratory. One way to overcome this problem is to increase the number of laboratory tests with regard to capacity of the laboratories. PMID:28607638

  8. Cost-price estimation of clinical laboratory services based on activity-based costing: A case study from a developing country.

    PubMed

    Mouseli, Ali; Barouni, Mohsen; Amiresmaili, Mohammadreza; Samiee, Siamak Mirab; Vali, Leila

    2017-04-01

    It is believed that laboratory tariffs in Iran don't reflect the real costs. This might expose private laboratories at financial hardship. Activity Based Costing is widely used as a cost measurement instrument to more closely approximate the true cost of operations. This study aimed to determine the real price of different clinical tests of a selected private clinical laboratory. This study was a cross sectional study carried out in 2015. The study setting was the private laboratories in the city of Kerman, Iran. Of 629 tests in the tariff book of the laboratory (relative value), 188 tests were conducted in the laboratory that used Activity Based Costing (ABC) methodology to estimate cost-price. Analyzing and cost-price estimating of laboratory services were performed by MY ABCM software Version 5.0. In 2015, the total costs were $641,645. Direct and indirect costs were 78.3% and 21.7% respectively. Laboratory consumable costs by 37% and personnel costs by 36.3% had the largest share of the costing. Also, group of hormone tests cost the most $147,741 (23.03%), and other tests group cost the least $3,611 (0.56%). Also after calculating the cost of laboratory services, a comparison was made between the calculated price and the private sector's tariffs in 2015. This study showed that there was a difference between costs and tariffs in the private laboratory. One way to overcome this problem is to increase the number of laboratory tests with regard to capacity of the laboratories.

  9. Studying Human Disease Genes in "Caenorhabditis Elegans": A Molecular Genetics Laboratory Project

    ERIC Educational Resources Information Center

    Cox-Paulson, Elisabeth A.; Grana, Theresa M.; Harris, Michelle A.; Batzli, Janet M.

    2012-01-01

    Scientists routinely integrate information from various channels to explore topics under study. We designed a 4-wk undergraduate laboratory module that used a multifaceted approach to study a question in molecular genetics. Specifically, students investigated whether "Caenorhabditis elegans" can be a useful model system for studying genes…

  10. The Laboratory for Terrestrial Physics

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Laboratory for Terrestrial Physics is dedicated to the advancement of knowledge in Earth and planetary science, by conducting innovative research using space technology. The Laboratory's mission and activities support the work and new initiatives at NASA's Goddard Space Flight Center (GSFC). The Laboratory's success contributes to the Earth Science Directorate as a national resource for studies of Earth from Space. The Laboratory is part of the Earth Science Directorate based at the GSFC in Greenbelt, MD. The Directorate itself is comprised of the Global Change Data Center (GCDC), the Space Data and Computing Division (SDCD), and four science Laboratories, including Laboratory for Terrestrial Physics, Laboratory for Atmospheres, and Laboratory for Hydrospheric Processes all in Greenbelt, MD. The fourth research organization, Goddard Institute for Space Studies (GISS), is in New York, NY. Relevant to NASA's Strategic Plan, the Laboratory ensures that all work undertaken and completed is within the vision of GSFC. The philosophy of the Laboratory is to balance the completion of near term goals, while building on the Laboratory's achievements as a foundation for the scientific challenges in the future.

  11. Laboratory study of biological retention for urban stormwater management.

    PubMed

    Davis, A P; Shokouhian, M; Sharma, H; Minami, C

    2001-01-01

    Urban stormwater runoff contains a broad range of pollutants that are transported to natural water systems. A practice known as biological retention (bioretention) has been suggested to manage stormwater runoff from small, developed areas. Bioretention facilities consist of porous soil, a topping layer of hardwood mulch, and a variety of different plant species. A detailed study of the characteristics and performance of bioretention systems for the removal of several heavy metals (copper, lead, and zinc) and nutrients (phosphorus, total Kjeldahl nitrogen [TKN], ammonium, and nitrate) from a synthetic urban stormwater runoff was completed using batch and column adsorption studies along with pilot-scale laboratory systems. The roles of the soil, mulch, and plants in the removal of heavy metals and nutrients were evaluated to estimate the treatment capacity of laboratory bioretention systems. Reductions in concentrations of all metals were excellent (> 90%) with specific metal removals of 15 to 145 mg/m2 per event. Moderate reductions of TKN, ammonium, and phosphorus levels were found (60 to 80%). Little nitrate was removed, and nitrate production was noted in several cases. The importance of the mulch layer in metal removal was identified. Overall results support the use of bioretention as a stormwater best management practice and indicate the need for further research and development.

  12. Study of LTPP laboratory resilient modulus test data and response characteristics.

    DOT National Transportation Integrated Search

    2002-10-01

    The resilient modulus of every unbound structural layer of the Long Term Pavement Performance (LTPP) Specific Pavement and : General Pavement Studies Test Sections is being measured in the laboratory using LTPP test protocol P46. A total of 2,014 : r...

  13. Harmonization of good laboratory practice requirements and laboratory accreditation programs.

    PubMed

    Royal, P D

    1994-09-01

    Efforts to harmonize Good Laboratory Practice (GLP) requirements have been underway through the Organization for Economic Cooperation and Development (OECD) since 1981. In 1985, a GLP panel was established to facilitate the practical implementation of the OECD/GLP program. Through the OECD/GLP program, Memoranda of Understanding (MOU) agreements which foster requirements for reciprocal data and study acceptance and unified GLP standards have been developed among member countries. Three OECD Consensus Workshops and three inspectors training workshops have been held. In concert with these efforts, several OECD countries have developed GLP accreditation programs, managed by local health and environmental ministries. In addition, Canada and the United States are investigating Laboratory Accreditation programs for environmental monitoring assessment and GLP-regulated studies. In the European Community (EC), the need for quality standards specifying requirements for production and international trade has promoted International Standards Organization (ISO) certification for certain products. ISO-9000 standards identify requirements for certification of quality systems. These certification programs may affect the trade and market of laboratories conducting GLP studies. Two goals identified by these efforts are common to both programs: first, harmonization and recognition of requirements, and second, confidence in the rigor of program components used to assess the integrity of data produced and study activities. This confidence can be promoted, in part, through laboratory inspection and screening processes. However, the question remains, will data produced by sanctioned laboratories be mutually accepted on an international basis?(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Change in argonne national laboratory: a case study.

    PubMed

    Mozley, A

    1971-10-01

    Despite traditional opposition to change within an institution and the known reluctance of an "old guard" to accept new managerial policies and techniques, the reactions suggested in this study go well beyond the level of a basic resistance to change. The response, indeed, drawn from a random sampling of Laboratory scientific and engineering personnel, comes close to what Philip Handler has recently described as a run on the scientific bank in a period of depression (1, p. 146). It appears that Argonne's apprehension stems less from the financial cuts that have reduced staff and diminished programs by an annual 10 percent across the last 3 fiscal years than from the administrative and conceptual changes that have stamped the institution since 1966. Administratively, the advent of the AUA has not forged a sense of collaborative effort implicit in the founding negotiations or contributed noticeably to increasing standards of excellence at Argonne. The AUA has, in fact, yet to exercise the constructive powers vested in them by the contract of reviewing and formulating long-term policy on the research and reactor side. Additionally, the University of Chicago, once the single operator, appears to have forfeited some of the trust and understanding that characterized the Laboratory's attitude to it in former years. In a period of complex and sensitive management the present directorate at Argonne is seriously dissociated from a responsible spectrum of opinion within the Laboratory. The crux of discontent among the creative scientific and engineering community appears to lie in a developed sense of being overadministered. In contrast to earlier periods, Argonne's professional staff feels a critical need for a voice in the formulation of Laboratory programs and policy. The Argonne senate could supply this mechanism. Slow to rally, their present concern springs from a firm conviction that the Laboratory is "withering on the vine." By contrast, the Laboratory director Powers

  15. Laboratory Studies Of Astrophysically-interesting Phosphorus-bearing Molecules

    NASA Astrophysics Data System (ADS)

    Ziurys, Lucy M.; Halfen, D. T.; Sun, M.; Clouthier, D. J.

    2009-05-01

    Over the past year, there has been a renewed interest in the presence of phosphorus-containing molecules in the interstellar medium. Recent observations have increased the number of known interstellar phosphorus-bearing species from two (PN, CP) to six with the identification of HCP, CCP, and PH3 in the carbon-rich circumstellar shell of IRC+10216 and PO in the oxygen-rich envelope of VY Canis Majoris. More species of this type may be present in the ISM, but laboratory rest frequencies, necessary for such detections, are not generally known for many potential molecules. To fill in this gap, we have been conducting measurements of the pure rotational spectra of phosphorus-containing molecules of astrophysical interest, using both millimeter/submm direct absorption and Fourier transform microwave (FTMW) spectroscopy. We have developed a new phosphorus source for this purpose. These methods cover the frequency ranges 65-850 GHz and 4-40 GHz, respectively. Our recent study of the CCP radical (X2Πr) using both of these techniques has resulted in its identification in IRC+10216. Rotational spectra of other molecules such as PCN, HPS, and CH3PH2 have been recorded. We will report on these species and additional new laboratory developments

  16. Laboratory Studies Offer New Insights for Mesospheric Nightglow

    NASA Astrophysics Data System (ADS)

    Kalogerakis, K. S.; Matsiev, D.

    2017-12-01

    The hydroxyl radical has a key role in the chemistry and energetics of the Earth's middle atmosphere. A detailed knowledge of the rate constants and relevant pathways for OH(high v) vibrational relaxation by atomic and molecular oxygen and their temperature dependence is absolutely critical for understanding mesospheric OH and extracting reliable chemical heating rates from atmospheric observations. We have developed laser-based experimental approaches to study the complex collisional energy transfer processes involving the OH radical and other relevant atmospheric species. Work in our laboratory indicated that the total removal rate constant for OH(v = 9) + O at room temperature is more than one order of magnitude larger than that for removal by O2. Thus, O atoms are expected to significantly influence the intensity and vibrational distribution extracted from the Meinel OH(v) emissions. Our recent laboratory measurements corroborated the aforementioned result for OH(v = 9) + O and provided important new insights on the multi-quantum energy transfer pathways involved. We will discuss relevant atmospheric implications, including warranted revisions of mesospheric nightglow models. Research supported by SRI International Internal R&D and NSF Aeronomy Grant AGS-1441896. Previously funded by NASA Geospace Science Grant NNX12AD09G.

  17. Life Sciences Laboratory 2 Fan Exhaust Mixing Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Flaherty, Julia E.; Antonio, Ernest J.

    An SF 6 tracer release was performed in the LSL-II ventilation stack over the weekend of March 5, 2016. The primary purpose of this study was to experimentally determine the gaseous concentration of material from a fume hood to the fan outlet, as well as at typical worker locations, to gain an understanding of potential worker exposures impacts. Five different fan operating configurations were utilized to ensure that the full spectrum of historical operating configurations was addressed. Some summary points from this study include: •Relatively high concentrations were observed within the stack area. –Between 50 and 100% of the exhaustmore » concentration may be observed within the stack. •Background concentrations were observed outside the stack area. –Workers outside the stack itself, but on the roof, are unlikely to be impacted by the exhaust. •Elevated concentrations on the order of 25% of the exhaust concentrations were observed within the Penthouse. •Transport time from a laboratory fume hood to the exhaust fan is within one to two minutes. •Penthouse concentrations climb from background levels to steady state over 15+ minutes. •Wind speed and wind direction did not play a significant role in the test outcomes. –A slight bias in the concentration distribution may be discernable based on wind speed and direction. •When both fans are operating, material from fume hoods on the east side preferentially flow through the east fan, while material from fume hoods on the west side preferentially flow through the west fan. This effectively doubles the concentration at that fan. This mixing study will inform other study components to develop a more complete picture of the worker potential exposure from LSL-II Rooftop activities. Estimating the mean concentration in the stack from chemical inventories and fume hood emissions for both current and historical laboratory activities is a separate effort. These estimates of mean ventilation concentrations

  18. LABORATORY STUDY ON THE OXIDATION OF ARSENIC III TO ARSENIC V

    EPA Science Inventory

    A one-year laboratory study was performed to determine the ability of seven oxidants to oxidize As(III) to As(V). These included chlorine, permanganate, ozone, chlorine dioxide, monochloramine, a solid-phase oxidizing media, and 254 nm ultraviolet light. Chlorine and permanganate...

  19. Effect of biofouling on the performance of amidoxime-based polymeric uranium adsorbents

    DOE PAGES

    Park, Jiyeon; Gill, Gary A.; Strivens, Jonathan E.; ...

    2016-01-27

    Here, the Marine Science Laboratory at the Pacific Northwest National Laboratory evaluated the impact of biofouling on uranium adsorbent performance. A surface modified polyethylene adsorbent fiber provided by Oak Ridge National Laboratory, AF adsorbent, was tested either in the presence or absence of light to simulate deployment in shallow or deep marine environments. 42-day exposure tests in column and flume settings showed decreased uranium uptake by biofouling. Uranium uptake was reduced by up to 30 %, in the presence of simulated sunlight, which also increased biomass accumulation and altered the microbial community composition on the fibers. These results suggest thatmore » deployment below the photic zone would mitigate the effects of biofouling, resulting in greater yields of uranium extracted from seawater.« less

  20. Laboratory studies of volcanic jets

    NASA Astrophysics Data System (ADS)

    Kieffer, Susan Werner; Sturtevant, Bradford

    1984-09-01

    The study of the fluid dynamics of violent volcanic eruptions by laboratory experiment is described, and the important fluid-dynamic processes that can be examined in laboratory models are discussed in detail. In preliminary experiments, pure gases are erupted from small reservoirs. The gases used are Freon 12 and Freon 22, two gases of high molecular weight and high density that are good analogs of heavy and particulate-laden volcanic gases; nitrogen, a moderate molecular weight, moderate density gas for which the thermodynamic properties are well known; and helium, a low molecular weight, lowdensity gas that is used as a basis for comparison with the behavior of the heavier gases and as an analog of steam, the gas that dominates many volcanic eruptions. Transient jets erupt from the reservoir into the laboratory upon rupture of a thin diaphragm at the exit of a convergent nozzle. The gas accelerates from rest in the reservoir to high velocity in the jet. Reservoir pressures and geometries are such that the fluid velocity in the jets is initially supersonic and later decays to subsonic. The measured reservoir pressure decreases as the fluid expands through repetitively reflecting rarefaction waves, but for the conditions of these experiments, a simple steady-discharge model is sufficient to explain the pressure decay and to predict the duration of the flow. Density variations in the flow field have been visualized with schlieren and shadowgraph photography. The observed structure of the jet is correlated with the measured pressure history. The starting vortex generated when the diaphragm ruptures becomes the head of the jet. Though the exit velocity is sonic, the flow head in the helium jet decelerates to about one-third of sonic velocity in the first few nozzle diameters, the nitrogen head decelerates to about three-fourths of sonic velocity, while Freon maintains nearly sonic velocity. The impulsive acceleration of reservoir fluid into the surrounding atmosphere

  1. DHM and serious games: a case-study oil and gas laboratories.

    PubMed

    Santos, V; Zamberlan, M; Streit, P; Oliveira, J; Guimarães, C; Pastura, F; Cid, G

    2012-01-01

    The aim in this paper is to present a research on the application of serious games for the design of laboratories in the oil and gas industries. The focus is in human virtual representation acquired from 3D scanning, human interaction, workspace layout and equipment designed considering ergonomics standards. The laboratory studies were simulated in Unity3D platform, which allows the users to control the DHM1 on the dynamic virtual scenario, in order to simulate work activities. This methodology can change the design process by improving the level of interaction between final users, managers and human factor teams. That helps to better visualize future work settings and improve the level of participation between all stakeholders.

  2. Diagnostic and laboratory test ordering in Northern Portuguese Primary Health Care: a cross-sectional study

    PubMed Central

    Sá, Luísa; Teixeira, Andreia Sofia Costa; Tavares, Fernando; Costa-Santos, Cristina; Couto, Luciana; Costa-Pereira, Altamiro; Hespanhol, Alberto Pinto; Santos, Paulo

    2017-01-01

    Objectives To characterise the test ordering pattern in Northern Portugal and to investigate the influence of context-related factors, analysing the test ordered at the level of geographical groups of family physicians and at the level of different healthcare organisations. Design Cross-sectional study. Setting Northern Primary Health Care, Portugal. Participants Records about diagnostic and laboratory tests ordered from 2035 family physicians working at the Northern Regional Health Administration, who served approximately 3.5 million Portuguese patients, in 2014. Outcomes To determine the 20 most ordered diagnostic and laboratory tests in the Northern Regional Health Administration; to identify the presence and extent of variations in the 20 most ordered diagnostic and laboratory tests between the Groups of Primary Care Centres and between health units; and to study factors that may explain these variations. Results The 20 most ordered diagnostic and laboratory tests almost entirely comprise laboratory tests and account for 70.9% of the total tests requested. We can trace a major pattern of test ordering for haemogram, glucose, lipid profile, creatinine and urinalysis. There was a significant difference (P<0.001) in test orders for all tests between Groups of Primary Care Centres and for all tests, except glycated haemoglobin (P=0.06), between health units. Generally, the Personalised Healthcare Units ordered more than Family Health Units. Conclusions The results from this study show that the most commonly ordered tests in Portugal are laboratory tests, that there is a tendency for overtesting and that there is a large variability in diagnostic and laboratory test ordering in different geographical and organisational Portuguese primary care practices, suggesting that there may be considerable potential for the rationalisation of test ordering. The existence of Family Health Units seems to be a strong determinant in decreasing test ordering by Portuguese family

  3. Investigating the effect of storm events on the particle size distribution in a combined sewer simulator.

    PubMed

    Biggs, C A; Prall, C; Tait, S; Ashley, R

    2005-01-01

    The changes in particle size of sewer sediment particles rapidly eroded from a previously deposited sediment bed are described, using a rotating annular flume as a laboratory scale sewer simulator. This is the first time that particle size distributions of eroded sewer sediments from a previously deposited sediment bed have been monitored in such a controlled experimental environment. Sediments from Loenen, The Netherlands and Dundee, UK were used to form deposits in the base of the annular flume (WL Delft Netherlands) with varying conditions for consolidation in order to investigate the effect of changing consolidation time, temperature and sediment type on the amount and size of particles eroded from a bed under conditions of increasing shear. The median size of the eroded particles did not change significantly with temperature, although the eroded suspended solids concentration was greater for the higher temperature under the same shear stresses, indicating a weaker bed deposit. An increase in consolidation time caused an increase in median size of eroded solids at higher bed shear stresses, and this was accompanied by higher suspended solids concentrations. As the shear stress increased, the solids eroded from the bed developed under a longer consolidation time (56 hours) tended towards a broad unimodal distribution, whilst the size distribution of solids eroded from beds developed under shorter consolidation times (18 or 42 hours) retained a bi- or tri-modal distribution. Using different types of sediment in the flume had a marked effect on the size of particles eroded.

  4. Laboratory Studies of Atmospheric Heterogeneous Chemistry

    NASA Technical Reports Server (NTRS)

    Keyser, L. F.; Leu, M-T.

    1993-01-01

    In the laboratory, ice films formed by freezing from the liquid or more frequently by deposition from the vapor phase have been used to simulate stratospheric cloud surfaces for measurements of reaction and uptake rates. To obtain intrinsic surface reaction probabilities that can be used in atmospheric models, the area of the film surface that actually takes part in the reaction must be known. It is important to know not only the total surface area but also the film morphology in order to determine where and how the surface is situated and, thus, what fraction of it is available for reaction. Information on the structure of these ice films has been obtained by using several experimental methods. In the sections that follow, these methods will be discussed, then the results will be used to construct a working model of the ice films, and finally the model will be applied to an experimental study of HC1 uptake by H_2O ice.

  5. Physical property studies in the USGS GHASTLI Laboratory

    USGS Publications Warehouse

    Winters, William J.; Waite, William F.; Hutchinson, Deborah R.; Mason, David H.

    2008-01-01

    One of the many challenges in studying methane hydrate is that it is unstable at typical surface pressure and temperature conditions. To enable methane hydrates and hydrate-bearing sediments to be formed, analyzed, and experimented with, the National Energy Technology Laboratory (NETL), and the U.S. Geological Survey (USGS) in Woods Hole, MA collaborated in the development of the Gas Hydrate And Sediment Test Laboratory Instrument (GHASTLI). Over the past decade, the USGS has been operating GHASTLI and collaborating in the development of new sample handling tools and procedures, in an effort to improve our ability to analyze methane hydrate in the lab. These tools will enable hydrate researchers to more confidently link field studies (for example geophysics or drilling) with theoretical and predictive studies, leading to a better understanding of the geological conditions and processes that control the growth and concentration of natural gas hydrates, how hydrates affect the properties of the host sediments, and how the hydrate-sediment system changes when hydrate dissociates and releases the previously bound gas. To date, GHASTLI has been used to measure natural samples from ODP Leg 164 (Blake Ridge off the U.S. southeast Atlantic margin), Leg 204 (Hydrate Ridge off the Pacific Northwest margin) and the Mallik well (Mackenzie Delta in northwestern Canada). Additional samples in the queue for analysis are from the Chevron Joint Industry Project Experiment in the Gulf of Mexico and most recently, from IODP Leg 311 off Vancouver Island. Several foreign nations have asked whether GHASTLI will be available to analyze samples that might be recovered during national drilling programs. The ability to perform lab testing of hydrates within sediments is one of the unique capabilities of GHASTLI that separates it from other simulators at NETL and elsewhere.

  6. A Laboratory Study Investigating the Feasibility of Applying Calcite-Type Coatings to Segregated Ballast Tanks

    DTIC Science & Technology

    1981-08-01

    A LABORATORY STUDY INVESTIGATIING THE FEASIBILITY OF APPLYING CALCITE -TYPE COATINGS TO SEGREGATED BALLAST TANKS AUGUST, 1981 Prepared by: Ocean City...Laboratory Study Investigating The Feasibility of Applying Calcite -Type Coatings to Segregated Ballast Tanks 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...Executive Summary List of Figures I. Conclusions II. Introduction III. Background-The Development and Use of Calcite -Type Coatings IV. Experimental

  7. Hydrology [Chapter 9

    Treesearch

    V. C. Hasfurther; G. L. Kerr; G. Parks; J. Wetstein

    1994-01-01

    Three Parshall flumes were installed within East and West Glacier Lakes watersheds during the summer of 1987. Each Parshall flume was prefabricated fiberglass construction fitted with a hypolon liner to bring as much groundwater flow as possible to the surface so that it could be measured by passing the water through the flume. The liner was buried as deep as was...

  8. Laboratory Activities in Israel

    ERIC Educational Resources Information Center

    Mamlok-Naaman, Rachel; Barnea, Nitza

    2012-01-01

    Laboratory activities have long had a distinctive and central role in the science curriculum, and science educators have suggested that many benefits accrue from engaging students in science laboratory activities. Many research studies have been conducted to investigate the educational effectiveness of laboratory work in science education in…

  9. Turning the tide: effects of river inflow and tidal amplitude on sandy estuaries in laboratory landscape experiments

    NASA Astrophysics Data System (ADS)

    Kleinhans, Maarten; Braat, Lisanne; Leuven, Jasper; Baar, Anne; van der Vegt, Maarten; van Maarseveen, Marcel; Markies, Henk; Roosendaal, Chris; van Eijk, Arjan

    2016-04-01

    Many estuaries formed over the Holocene through a combination of fluvial and coastal influxes, but how estuary planform shape and size depend on tides, wave climate and river influxes remains unclear. Here we use a novel tidal flume setup of 20 m length by 3 m width, the Metronome (http://www.uu.nl/metronome), to create estuaries and explore a parameter space for the simple initial condition of a straight river in sandy substrate. Tidal currents capable of transporting sediment in both the ebb and flood phase because they are caused by periodic tilting of the flume rather than the classic method of water level fluctuation. Particle imaging velocimetry and a 1D shallow flow model demonstrate that this principle leads to similar sediment mobility as in nature. Ten landscape experiments recorded by timelapse overhead imaging and AGIsoft DEMs of the final bed elevation show that absence of river inflow leads to short tidal basins whereas even a minor discharge leads to long convergent estuaries. Estuary width and length as well as morphological time scale over thousands of tidal cycles strongly depend on tidal current amplitude. Paddle-generated waves subdue the ebb delta causing stronger tidal currents in the basin. Bar length-width ratios in estuaries are slightly larger to those in braided rivers in experiments and nature. Mutually evasive ebb- and flood-dominated channels are ubiquitous and appear to be formed by an instability mechanism with growing bar and bifurcation asymmetry. Future experiments will include mud flats and live vegetation.

  10. Laboratory medicine education in Lithuania.

    PubMed

    Kucinskiene, Zita Ausrele; Bartlingas, Jonas

    2011-01-01

    In Lithuania there are two types of specialists working in medical laboratories and having a university degree: laboratory medicine physicians and medical biologists. Both types of specialists are officially being recognized and regulated by the Ministry of Health of Lithuania. Laboratory medicine physicians become specialists in laboratory medicine after an accredited 4-year multidisciplinary residency study program in Laboratory Medicine. The residency program curriculum for laboratory medicine physicians is presented. On December 9, 2009 the Equivalence of Standards for medical specialists was accepted and Lithuanian medical specialists in Clinical Chemistry and Laboratory Medicine can now apply for EC4 registration. Medical biologists become specialists in laboratory medicine after an accredited 2-year master degree multidisciplinary study program in Medical Biology, consisting of 80 credits. Various postgraduate advanced training courses for the continuous education of specialists in laboratory medicine were first introduced in 1966. Today it covers 1-2-week courses in different subspecialties of laboratory medicine. They are obligatory for laboratory medicine physicians for the renewal of their license. It is not compulsory for medical biologists to participate in these courses. The Centre of Laboratory Diagnostics represents a place for the synthesis and application of the basic sciences, the performance of research in various fields of laboratory medicine, as well as performance of thousands of procedures daily and provision of specific teaching programs.

  11. Good Laboratory Practice. Part 3. Implementing Good Laboratory Practice in the Analytical Lab

    ERIC Educational Resources Information Center

    Wedlich, Richard C.; Pires, Amanda; Fazzino, Lisa; Fransen, Joseph M.

    2013-01-01

    Laboratories submitting experimental results to the Food and Drug Administration (FDA) or the Environmental Protection Agency (EPA) in support of Good Laboratory Practice (GLP) nonclinical laboratory studies must conduct such work in compliance with the GLP regulations. To consistently meet these requirements, lab managers employ a "divide…

  12. Phase transition behavior of sediment transport at the sand-mud interface, across scales from flumes to the large rivers

    NASA Astrophysics Data System (ADS)

    Ma, H.; Nittrouer, J. A.; Wu, B.; Zhang, Y.; Mohrig, D. C.; Lamb, M. P.; Wang, Y.; Fu, X.; Moodie, A. J.; Naito, K.; Parker, G.

    2017-12-01

    Sediment dispersal and deposition creates deltaic landscapes, establishes coastlines, and produces fertile floodplains, all of which serve as critical landforms inhabited by a large proportion of humankind. If poorly managed, sediment loads in these environments can elevate and clog channels, thereby enhancing hazards such as severe flooding. Predictive descriptions of sediment loads, however, are not well constrained, especially for fine-grained (silt and very-fine sand) dispersal systems, which often include river deltas and coastlines. Here, we show efforts to collect and analyze an extensive sediment load database for fine-grained channels, spanning from small flume experiments to large rivers, in order to evaluate the nature of sediment flux. Our analyses determined that sediment transport exhibits two distinct transport phases, separated by a discontinuous transition, whereby sediment flux differs by one to two orders of magnitude. It is determined that the transition responds to the bed material grain size, and we propose a phase diagram based on this metric alone. These findings help elucidate why previous theories of sediment transport at the sand-silt interface, which are typically continuous, are not able to give satisfactory predictions across different scales and environments. Our work serves to help evaluate anthropic influences on rivers, deltas, and coastlines, and can be applied to better constrain sediment flux of paleo-fluvial systems found on Earth and Mars. For example, in situ measurements of sediment flux for the silty-sandy bed of the lower Yellow River, China, validate the aforementioned phase transition behavior, and illustrate that the channel resides near the transition of high to low efficiency transport modes. Recent dam construction and resulting downstream coarsening of the bed via armoring, however, might lead to the unintended consequence of enhancing flood risk by driving the system to a low efficiency transport mode with high

  13. Habitat selection and adult-recruit interactions in Pectinaria koreni (Malmgren) (Annelida: Polychaeta) post-larval populations: Results of flume experiments

    NASA Astrophysics Data System (ADS)

    Olivier, Frédéric; Desroy, Nicolas; Retière, Christian

    1996-12-01

    The fate of recently settled populations of soft-bottom invertebrates depends not only on dispersal of pelagic larvae by tidal currents but also on other physical ( e. g. resuspension) and biological mechanisms ( e.g. habitat selection and adult-recruit interactions) acting at the water-substratum interface. To assess the relative importance of such processes under megatidal conditions in the Abra alba community of the eastern Baie de Seine (English Channel), flume experiments were conducted on post-larvae of the dominant polychaete species, Pectinaria koreni. Habitat selection by post-larvae of P. koreni was determined in a first set of experiments, where individuals were sowed either on a suitable or on an unsuitable substratum. Once resuspended, post-larvae were given a choice between two highly contrasting treatments with a natural organic-rich muddy sand and a bare flat PVC surface. P. koreni post-larvae were able to leave an unfavourable substratum into which they had initially burrowed and reach a more suitable substrate by drifting (induced by the secretion of mucus) before final settlement. The influence of adults on habitat selection and survival of P. koreni post-larvae was analysed in a second set of experiments, where individuals were sowed onto a suitable sediment with adults (test treatment) or without (control treatment). The presence of conspecific adults induced a high resuspension rate of the post-larvae. Drifting occurred mainly just after the introduction of the current and affected the whole experimental population, regardless of size. Such a response seems to be related to the intense bioturbation caused by the sub-surface deposit-feeding habit of the adults, which alters the boundary-layer flow. In contrast, the presence of adults of Owenia fusiformis, another dominant polychaete of the Abra alba community, led to an enhanced recruitment by a reduction in post-larvae resuspension. In fact, at low shear velocities, dense aggregates of tubes

  14. Procedures of Exercise Physiology Laboratories

    NASA Technical Reports Server (NTRS)

    Bishop, Phillip A.; Fortney, Suzanne; Greenisen, Michael; Siconolfi, Steven F.; Bamman, Marcas M.; Moore, Alan D., Jr.; Squires, William

    1998-01-01

    This manual describes the laboratory methods used to collect flight crew physiological performance data at the Johnson Space Center. The Exercise Countermeasures Project Laboratory is a standard physiology laboratory; only the application to the study of human physiological adaptations to spaceflight is unique. In the absence of any other recently published laboratory manual, this manual should be a useful document staffs and students of other laboratories.

  15. Laboratories | NREL

    Science.gov Websites

    | Z A Accelerated Exposure Testing Laboratory Advanced Optical Materials Laboratory Advanced Thermal Laboratory Structural Testing Laboratory Surface Analysis Laboratory Systems Performance Laboratory T Thermal Storage Materials Laboratory Thermal Storage Process and Components Laboratory Thin-Film Deposition

  16. The Effect of Suspended Sediment Transport and Deposition on Streambed Clogging Under Losing and Gaining Flow Conditions

    NASA Astrophysics Data System (ADS)

    Fox, A.; Packman, A. I.; Preziosi-Ribero, A.; Li, A.; Arnon, S.

    2017-12-01

    Sediment transport and deposition in streams can affect streambed hydraulic characteristics due to clogging, reduce water fluxes through the hyporheic zone, and thus expected to affect biogeochemical processes. Processes affecting deposition of suspended particles were systematically studied under various overlying velocities but without taking into account the interactions with groundwater. This is despite the fact that the interaction with groundwater were shown to play an important role in deposition patterns of fine sediments in field studies. The objective of this study was to evaluate the effect of losing and gaining fluxes on suspended sediment depositional patterns and on hyporheic exchange fluxes. Experiments were conducted in a laboratory flume system (640 cm long and 30 cm wide) that has a capacity to enforce losing or gaining flow conditions. The flume was packed with homogenous sand, while suspended sediment deposition was evaluated by adding kaolinite particles to the water and following the deposition rate by particle disappearance from the bulk water. Consecutive additions of kaolinite were done, while hyporheic exchange fluxes were evaluated by conducting NaCl tracer experiments between each kaolinite additions. Furthermore, dye injections were used to visualize the flow patterns in the streambed using time-lapse photography through the transparent sidewalls of the flume. Hyporheic exchange and particle tracking simulations were done to assess the results of particle deposition and feedbacks between hyporheic flow, particle transport, and streambed clogging. Experimental results showed that the deposition of clay decreases with increasing amount of clay concentration in the sediment. Hyporheic exchange flux decreases linearly with increasing amount of clay added to the system and the region of active hyporheic exchange was confined to the upper part of the sediment. Understanding the particle deposition mechanisms under losing and gaining flow

  17. The Effect of Guided-Inquiry Laboratory Experiments on Science Education Students' Chemistry Laboratory Attitudes, Anxiety and Achievement

    ERIC Educational Resources Information Center

    Ural, Evrim

    2016-01-01

    The study aims to search the effect of guided inquiry laboratory experiments on students' attitudes towards chemistry laboratory, chemistry laboratory anxiety and their academic achievement in the laboratory. The study has been carried out with 37 third-year, undergraduate science education students, as a part of their Science Education Laboratory…

  18. 21 CFR 58.49 - Laboratory operation areas.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Laboratory operation areas. 58.49 Section 58.49... LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Facilities § 58.49 Laboratory operation areas... procedures required by nonclinical laboratory studies. [52 FR 33780, Sept. 4, 1987] ...

  19. 21 CFR 58.49 - Laboratory operation areas.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Laboratory operation areas. 58.49 Section 58.49... LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Facilities § 58.49 Laboratory operation areas... procedures required by nonclinical laboratory studies. [52 FR 33780, Sept. 4, 1987] ...

  20. 21 CFR 58.49 - Laboratory operation areas.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Laboratory operation areas. 58.49 Section 58.49... LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Facilities § 58.49 Laboratory operation areas... procedures required by nonclinical laboratory studies. [52 FR 33780, Sept. 4, 1987] ...

  1. Laboratory plant study on the melting process of asbestos waste

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sakai, Shinichi; Terazono, Atsushi; Takatsuki, Hiroshi

    The melting process was studied as a method of changing asbestos into non-hazardous waste and recovering it as a reusable resource. In an initial effort, the thermal behaviors of asbestos waste in terms of physical and chemical structure have been studied. Then, 10 kg/h-scale laboratory plant experiments were carried out. By X-ray diffraction analysis, the thermal behaviors of sprayed-on asbestos waste revealed that chrysotile asbestos waste change in crystal structure at around 800 C, and becomes melted slag, mainly composed of magnesium silicate, at around 1,500 C. Laboratory plant experiments on the melting process of sprayed-on asbestos have shown thatmore » melted slag can be obtained. X-ray diffraction analysis of the melted slag revealed crystal structure change, and SEM analysis showed the slag to have a non-fibrous form. And more, TEM analysis proved the very high treatment efficiency of the process, that is, reduction of the asbestos content to 1/10{sup 6} as a weight basis. These analytical results indicate the effectiveness of the melting process for asbestos waste treatment.« less

  2. Variability in baseline laboratory measurements of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    PubMed

    Ladwig, R; Vigo, A; Fedeli, L M G; Chambless, L E; Bensenor, I; Schmidt, M I; Vidigal, P G; Castilhos, C D; Duncan, B B

    2016-08-01

    Multi-center epidemiological studies must ascertain that their measurements are accurate and reliable. For laboratory measurements, reliability can be assessed through investigation of reproducibility of measurements in the same individual. In this paper, we present results from the quality control analysis of the baseline laboratory measurements from the ELSA-Brasil study. The study enrolled 15,105 civil servants at 6 research centers in 3 regions of Brazil between 2008-2010, with multiple biochemical analytes being measured at a central laboratory. Quality control was ascertained through standard laboratory evaluation of intra- and inter-assay variability and test-retest analysis in a subset of randomly chosen participants. An additional sample of urine or blood was collected from these participants, and these samples were handled in the same manner as the original ones, locally and at the central laboratory. Reliability was assessed with the intraclass correlation coefficient (ICC), estimated through a random effects model. Coefficients of variation (CV) and Bland-Altman plots were additionally used to assess measurement variability. Laboratory intra and inter-assay CVs varied from 0.86% to 7.77%. From test-retest analyses, the ICCs were high for the majority of the analytes. Notably lower ICCs were observed for serum sodium (ICC=0.50; 95%CI=0.31-0.65) and serum potassium (ICC=0.73; 95%CI=0.60-0.83), due to the small biological range of these analytes. The CVs ranged from 1 to 14%. The Bland-Altman plots confirmed these results. The quality control analyses showed that the collection, processing and measurement protocols utilized in the ELSA-Brasil produced reliable biochemical measurements.

  3. 23. DETAIL VIEW OF THE C. 1905 DAYTON GLOBE TURBINE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. DETAIL VIEW OF THE C. 1905 DAYTON GLOBE TURBINE THAT IS STILL EXTANT IN THE SECOND FLUME (COUNTING FROM THE DOWNSTREAM FLUME TOWARDS THE UPSTREAM FLUMES) BENEATH THE GENERATOR FLOOR. THE DYNAMO THIS TURBINE WAS ATTACHED TO IS NO LONGER EXTANT. - Potomac Power Plant, On West Virginia Shore of Potomac River, about 1 mile upriver from confluence with Shenandoah River, Harpers Ferry, Jefferson County, WV

  4. Folsomia Candida--An Ideal Organism for Population Studies in the Laboratory

    ERIC Educational Resources Information Center

    Usher, M. B.; Stoneman, C. F.

    1977-01-01

    Folsomia candida is presented as an ideal organism for population studies that can be carried out cheaply and easily in school laboratory conditions. Means of identifying, obtaining, and culturing these organisms are described together with some indication of the kinds of investigations which can be performed. (Author/MA)

  5. FLARE (Facility for Laboratory Reconnection Experiments): A Major Next-Step for Laboratory Studies of Magnetic Reconnection

    NASA Astrophysics Data System (ADS)

    Ji, Hantao; Bhattacharjee, A.; Prager, S.; Daughton, W.; Bale, Stuart D.; Carter, T.; Crocker, N.; Drake, J.; Egedal, J.; Sarff, J.; Fox, W.; Jara-Almonte, J.; Myers, C.; Ren, Y.; Yamada, M.; Yoo, J.

    2015-04-01

    A new intermediate-scale plasma experiment, called the Facility for Laboratory Reconnection Experiments or FLARE (flare.pppl.gov), is under construction at Princeton as a joint project by five universities and two national labs to study magnetic reconnection in regimes directly relevant to heliophysical and astrophysical plasmas. The currently existing small-scale experiments have been focusing on the single X-line reconnection process in plasmas either with small effective sizes or at low Lundquist numbers, both of which are typically very large in natural plasmas. These new regimes involve multiple X-lines as guided by a reconnection "phase diagram", in which different coupling mechanisms from the global system scale to the local dissipation scale are classified into different reconnection phases [H. Ji & W. Daughton, Phys. Plasmas 18, 111207 (2011)]. The design of the FLARE device is based on the existing Magnetic Reconnection Experiment (MRX) (mrx.pppl.gov) and is to provide experimental access to the new phases involving multiple X-lines at large effective sizes and high Lundquist numbers, directly relevant to magnetospheric, solar wind, and solar coronal plasmas. After a brief summary of recent laboratory results on the topic of magnetic reconnection, the motivating major physics questions, the construction status, and the planned collaborative research especially with heliophysics communities will be discussed.

  6. Pre-Service Chemistry Teachers' Competencies in the Laboratory: A Cross-Grade Study in Solution Preparation

    ERIC Educational Resources Information Center

    Karatas, F. O.

    2016-01-01

    One of the prerequisites for chemistry teacher candidates is to demonstrate certain laboratory skills. This article aims to determine and discuss the competencies of pre-service chemistry teachers in a chemistry laboratory context working with solution chemistry content. The participants in this study consisted of a group of pre-service chemistry…

  7. Calgary Laboratory Services

    PubMed Central

    2015-01-01

    Calgary Laboratory Services provides global hospital and community laboratory services for Calgary and surrounding areas (population 1.4 million) and global academic support for the University of Calgary Cumming School of Medicine. It developed rapidly after the Alberta Provincial Government implemented an austerity program to address rising health care costs and to address Alberta’s debt and deficit in 1994. Over roughly the next year, all hospital and community laboratory test funding within the province was put into a single budget, fee codes for fee-for-service test billing were closed, roughly 40% of the provincial laboratory budget was cut, and roughly 40% of the pathologists left the province of Alberta. In Calgary, in the face of these abrupt changes in the laboratory environment, private laboratories, publicly funded hospital laboratories and the medical school department precipitously and reluctantly merged in 1996. The origin of Calgary Laboratory Services was likened to an “unhappy shotgun marriage” by all parties. Although such a structure could save money by eliminating duplicated services and excess capacity and could provide excellent city-wide clinical service by increasing standardization, it was less clear whether it could provide strong academic support for a medical school. Over the past decade, iterations of the Calgary Laboratory Services model have been implemented or are being considered in other Canadian jurisdictions. This case study analyzes the evolution of Calgary Laboratory Services, provides a metric-based review of academic performance over time, and demonstrates that this model, essentially arising as an unplanned experiment, has merit within a Canadian health care context. PMID:28725754

  8. Definition of experiments and instruments for a communication/navigation research laboratory. Volume 3: Laboratory descriptions

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The following study objectives are covered: (1) identification of major laboratory equipment; (2) systems and operations analysis in support of the laboratory design; and (3) conceptual design of the comm/nav research laboratory.

  9. Participation in Performance-Evaluation Studies by U.S. Geological Survey National Water Quality Laboratory

    USGS Publications Warehouse

    Glodt, Stephen R.; Pirkey, Kimberly D.

    1998-01-01

    Performance-evaluation studies provide customers of the U.S. Geological Survey National Water Quality Laboratory (NWQL) with data needed to evaluate performance and to compare of select laboratories for analytical work. The NWQL participates in national and international performance-evaluation (PE) studies that consist of samples of water, sediment, and aquatic biological materials for the analysis of inorganic constituents, organic compounds, and radionuclides. This Fact Sheet provides a summary of PE study results from January 1993 through April 1997. It should be of particular interest to USGS customers and potential customers of the NWQL, water-quality specialists, cooperators, and agencies of the Federal Government.

  10. A comparison of a biological sciences curriculum study (BSCS) laboratory and a traditional laboratory on student achievement at two private liberal arts colleges

    NASA Astrophysics Data System (ADS)

    Hall, Donald A.; McCurdy, Donald W.

    The purpose of this experiment was to compare an inquiry-oriented Biological Sciences Curriculum Study (BSCS) style laboratory approach with a more directive traditional approach on student outcomes in the cognitive and affective domains of learning at two private, midwestern liberal-arts colleges. The BSCS approach emphasized basic and integrated science processes, concept development through extensive questioning, and increased student discretion, while the traditional approach contained highly structured, more prescriptive, teacher-oriented activities. Intact laboratory sections of students enrolled in introductory general biology at two private liberal-arts colleges were randomly selected into two treatment groups. Pretest and posttest measures were taken on three dependent variables: (1) biological content achievement, measured with a researcher-generated Test on Biology Laboratory Concepts, (2) reasoning ability, measured with the Group Assessment of Logical Thinking, and (3) attitude toward biology, measured with the Biology Student Behavior Inventory. Analysis of covariance indicated the experimental group (n = 60) using the BSCS-style laboratory approach scored significantly higher than the comparison group (n = 59) in levels of performance on biology content achievement, F(1, 114) = 4.07, p < 0.05. There were no significant differences between the two groups in performance levels on attitude toward biology or on reasoning ability. However, both groups experienced a 15-percent increase in the number of formal thinkers as indicated by pretest-posttest gain scores on the reasoning ability test. These results lend support to the hypothesis that a BSCS-style laboratory approach fosters desired learner outcomes at the postsecondary level. In addition, these findings support the notion that the science laboratory may be used as a primary vehicle to promote formal reasoning skills.

  11. Evaluation of critical shear stresses for consolidated cohesive sediment depositions by using PIV compared with field measurements

    NASA Astrophysics Data System (ADS)

    Harb, Gabriele; Haun, Stefan

    2013-04-01

    Reservoir sedimentation is a common problem today. Due to the reduced flow velocities, turbulences and bed shear stresses the transported sediment load start to settle. These depositions reduce the worldwide average storage capacity in the range of about 1% per year. However, depending on the climate conditions and the geology in the catchment area this value may vary strongly. Therefore sediment management tasks, especially the removal of already accumulated sediments, have to be developed for each reservoir separately. The critical bed shear stress is a key parameter used to evaluate the different management tasks and depend strongly on the grain size distribution of the inflowing sediments. However, depositions which contain fine particles like clay and silt increase the critical bed shear stress due to occurring cohesive forces and the use of the Shield curve for evaluating the critical shear stress is no longer valid. Additional data is required for estimating the valid critical shear stress at the reservoir bed. In this study the critical shear stress was evaluated for cohesive sediment samples, taken from two different reservoirs, in a flume in the laboratory. The sediment samples were placed in an installed double bottom in the research flume and the discharge was increased stepwise until mass erosion took place (determined by visual inspection). A 2D PIV device was used to measure the flow conditions (velocities and turbulences) over the sediment sample. The obtained values were used to calculate the bed shear stress for the specific discharge rate by the gravity method and the Reynolds stress method. The results of both methods showed good agreement in the comparison of the values, what indicates that nearly uniform flow conditions occurred in the flume. The results from this study showed that the behaviour of natural cohesive sediments depend strongly on the natural conditions as a result of physical, chemical and biological processes. In this case

  12. Teaching Laboratory Renovation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Zuhairi, Ali Jassim; Al-Dahhan, Wedad; Hussein, Falah

    Scientists at universities across Iraq are actively working to report actual incidents and accidents occurring in their laboratories, as well as structural improvements made to improve safety and security, to raise awareness and encourage openness, leading to widespread adoption of robust Chemical Safety and Security (CSS) practices. The improvement of students’ understanding of concepts in science and its applications, practical scientific skills and understanding of how science and scientists work in laboratory experiences have been considered key aspects of education in science for over 100 years. Facility requirements for the necessary level of safety and security combined with specific requirementsmore » relevant to the course to be conducted dictate the structural design of a particular laboratory, and the design process must address both. This manuscript is the second in a series of five case studies describing laboratory incidents, accidents, and laboratory improvements. We summarize the process used to guide a major renovation of the chemistry instructional laboratory facilities at Al-Nahrain University and discuss lessons learned from the project.« less

  13. Gene Polymorphism Studies in a Teaching Laboratory

    ERIC Educational Resources Information Center

    Shultz, Jeffry

    2009-01-01

    I present a laboratory procedure for illustrating transcription, post-transcriptional modification, gene conservation, and comparative genetics for use in undergraduate biology education. Students are individually assigned genes in a targeted biochemical pathway, for which they design and test polymerase chain reaction (PCR) primers. In this…

  14. Addressing the key communication barriers between microbiology laboratories and clinical units: a qualitative study

    PubMed Central

    Skodvin, Brita; Aase, Karina; Brekken, Anita Løvås; Charani, Esmita; Lindemann, Paul Christoffer; Smith, Ingrid

    2017-01-01

    Abstract Background Many countries are on the brink of establishing antibiotic stewardship programmes in hospitals nationwide. In a previous study we found that communication between microbiology laboratories and clinical units is a barrier to implementing efficient antibiotic stewardship programmes in Norway. We have now addressed the key communication barriers between microbiology laboratories and clinical units from a laboratory point of view. Methods Qualitative semi-structured interviews were conducted with 18 employees (managers, doctors and technicians) from six diverse Norwegian microbiological laboratories, representing all four regional health authorities. Interviews were recorded and transcribed verbatim. Thematic analysis was applied, identifying emergent themes, subthemes and corresponding descriptions. Results The main barrier to communication is disruption involving specimen logistics, information on request forms, verbal reporting of test results and information transfer between poorly integrated IT systems. Furthermore, communication is challenged by lack of insight into each other’s area of expertise and limited provision of laboratory services, leading to prolonged turnaround time, limited advisory services and restricted opening hours. Conclusions Communication between microbiology laboratories and clinical units can be improved by a review of testing processes, educational programmes to increase insights into the other’s area of expertise, an evaluation of work tasks and expansion of rapid and point-of-care test services. Antibiotic stewardship programmes may serve as a valuable framework to establish these measures. PMID:28633405

  15. Service Quality and Patient Satisfaction: An Exploratory Study of Pathology Laboratories in Jaipur.

    PubMed

    Agarwal, Anuradha; Singh, Maithili R P

    2016-01-01

    One of the most important parts of healthcare system is diagnostics. Nowadays, Indians have become more aware of their health, due to improved and better availability of health related information, increase in medical tourism, and expanding health insurance. The demand for better diagnostic facilities have increased with the increase in lifestyle related diseases, excesses use of chemicals in agriculture practices and change in food habits. It is expected that the Indian diagnostic market will grow from USD $5 billion in the year 2012 to USD $32 billion by the year 2020 with 20% CAGR (India Brand Equity Foundation 2015 ). Today patients have easy access of information regarding the health services and they have become more concerned about it as they look forward to receiving the maximum value for their money. To win the confidence of the patients and to maintain that trust, it is required to deliver the right services to the right person at the right time. The purpose of this study was to develop a scale to measure the service quality at pathology laboratory. A thorough review of literature revealed that there are studies related to healthcare service quality but there is no such established scale to measure service quality of pathology laboratory. Thus, the authors strived to develop a reliable and valid instrument to measure the patients' perception toward pathology laboratory service quality. For this exploratory study was conducted on the sample of 80 patients of the laboratories in Jaipur city. The reliability and factor structures were tested to purify the scale. The findings revealed 13 items, comprising of three dimensions of service quality: responsiveness, tangibility, and reliability.

  16. Change Agent Strategies: A Study of the Michigan-Ohio Regional Educational Laboratory.

    ERIC Educational Resources Information Center

    Miller, Peggy Lynne

    This dissertation reports on a study of the planning and development activities of the Michigan-Ohio Regional Educational Laboratory (MOREL). The study attempted to assess (1) whether MOREL has accepted a change agent role, and (2) whether it has taken action that indicates recognition of what is known through the literature and research about…

  17. Perception and action in swimming: Effects of aquatic environment on upper limb inter-segmental coordination.

    PubMed

    Guignard, Brice; Rouard, Annie; Chollet, Didier; Ayad, Omar; Bonifazi, Marco; Dalla Vedova, Dario; Seifert, Ludovic

    2017-10-01

    This study assessed perception-action coupling in expert swimmers by focusing on their upper limb inter-segmental coordination in front crawl. To characterize this coupling, we manipulated the fluid flow and compared trials performed in a swimming pool and a swimming flume, both at a speed of 1.35ms -1 . The temporal structure of the stroke cycle and the spatial coordination and its variability for both hand/lower arm and lower arm/upper arm couplings of the right body side were analyzed as a function of fluid flow using inertial sensors positioned on the corresponding segments. Swimmers' perceptions in both environments were assessed using the Borg rating of perceived exertion scale. Results showed that manipulating the swimming environment impacts low-order (e.g., temporal, position, velocity or acceleration parameters) and high-order (i.e., spatial-temporal coordination) variables. The average stroke cycle duration and the relative duration of the catch and glide phases were reduced in the flume trial, which was perceived as very intense, whereas the pull and push phases were longer. Of the four coordination patterns (in-phase, anti-phase, proximal and distal: when the appropriate segment is leading the coordination of the other), flume swimming demonstrated more in-phase coordination for the catch and glide (between hand and lower arm) and recovery (hand/lower arm and lower arm/upper arm couplings). Conversely, the variability of the spatial coordination was not significantly different between the two environments, implying that expert swimmers maintain consistent and stable coordination despite constraints and whatever the swimming resistances. Investigations over a wider range of velocities are needed to better understand coordination dynamics when the aquatic environment is modified by a swimming flume. Since the design of flumes impacts significantly the hydrodynamics and turbulences of the fluid flow, previous results are mainly related to the

  18. Reliability on intra-laboratory and inter-laboratory data of hair mineral analysis comparing with blood analysis.

    PubMed

    Namkoong, Sun; Hong, Seung Phil; Kim, Myung Hwa; Park, Byung Cheol

    2013-02-01

    Nowadays, although its clinical value remains controversial institutions utilize hair mineral analysis. Arguments about the reliability of hair mineral analysis persist, and there have been evaluations of commercial laboratories performing hair mineral analysis. The objective of this study was to assess the reliability of intra-laboratory and inter-laboratory data at three commercial laboratories conducting hair mineral analysis, compared to serum mineral analysis. Two divided hair samples taken from near the scalp were submitted for analysis at the same time, to all laboratories, from one healthy volunteer. Each laboratory sent a report consisting of quantitative results and their interpretation of health implications. Differences among intra-laboratory and interlaboratory data were analyzed using SPSS version 12.0 (SPSS Inc., USA). All the laboratories used identical methods for quantitative analysis, and they generated consistent numerical results according to Friedman analysis of variance. However, the normal reference ranges of each laboratory varied. As such, each laboratory interpreted the patient's health differently. On intra-laboratory data, Wilcoxon analysis suggested they generated relatively coherent data, but laboratory B could not in one element, so its reliability was doubtful. In comparison with the blood test, laboratory C generated identical results, but not laboratory A and B. Hair mineral analysis has its limitations, considering the reliability of inter and intra laboratory analysis comparing with blood analysis. As such, clinicians should be cautious when applying hair mineral analysis as an ancillary tool. Each laboratory included in this study requires continuous refinement from now on for inducing standardized normal reference levels.

  19. Laboratory Astrophysics in Support of the Study of Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    den Hartog, Betsy

    2017-04-01

    One of the outstanding questions in our understanding of the Universe is how the elements were made. Only a few of the lightest or primordial nuclei were made just after the Big Bang. Other light nuclei up to the iron (Fe)-group are made by fusion reactions in the interior of stars. Heavier nuclei are made primarily via neutron-capture events which are categorized as either slow or rapid, the s-process or r-process, respectively. Although s-process neutron-capture is fairly well understood, the r-process, which occurs in neutron dense (explosive) environments, remains more elusive. In recent years, progress has been made in the understanding of r-process nucleosynthesis through the study of elemental abundances in metal-poor stars. These stars, which are among the oldest objects in our Galaxy, contain a fossil record of the elemental mix of the surrounding interstellar medium when they formed. The improvement of both the accuracy and precision of elemental abundances in metal-poor stars has required a long-term effort to improve the necessary laboratory data - first for the rare earth elements and more recently for the Fe-group. In this talk I will describe our laboratory effort measuring atomic transition probabilities, which are determined from a combination of radiative lifetimes and emission branching fractions. I will then show some examples of the application of our laboratory data to the determination of metal-poor star elemental abundances and discuss insights that can be gleaned from these improved data. Work in collaboration with (and supported by) Jim Lawler (NSF Grant AST-1516182, NASA Grant NNX16AE96G), Chris Sneden (NSF Grant AST-1211585) and John Cowan (NSF Grant PHY-1430152 (JINA Center for the Evolution of the Elements)), among others.

  20. Evaluation of Intake Efficiencies and Associated Sediment-Concentration Errors in US D-77 Bag-Type and US D-96-Type Depth-Integrating Suspended-Sediment Samplers

    NASA Astrophysics Data System (ADS)

    Sabol, T. A.; Topping, D. J.; Griffiths, R. E.

    2011-12-01

    Accurate measurements of suspended-sediment concentration require suspended-sediment samplers to operate isokinetically with an intake-efficiency of 1.0 ± 0.10. Results from 1940s Federal Interagency Sedimentation Project (FISP) laboratory experiments show that when the intake efficiency does not equal 1.0, suspended-sediment samplers either under- or oversample sediment relative to water, leading to biases in suspended-sediment concentration. The majority of recent FISP sampler development and testing has been conducted under uniform flow conditions using flume and slack-water tow tests, with little testing in actual turbulent rivers. Recent work has focused on the hydraulic characteristics and intake efficiencies of these samplers, without field investigations of the accuracy of the suspended-sediment data collected with these samplers. When depth-integrating suspended-sediment samplers are deployed under the non-uniform and turbulent conditions that exist in rivers, multiple factors may contribute to departures from isokinetic sampling. This introduces errors into the suspended-sediment data that may not be predictable on the basis of flume and tow tests alone. This study (1) evaluates the intake efficiencies of the older US D-77 bag-type and newer, FISP-approved US D-96 samplers at multiple river cross sections under a range of flow conditions; (2) examines if water temperature and sampling duration explain measured differences in intake efficiency between samplers and between laboratory and field tests; (3) models and predicts the directions and magnitudes of errors in measured suspended-sand concentration; and (4) determines if the relative differences in suspended-sediment concentration in a variety of size classes are consistent with the differences expected on the basis of the 1940s FISP-laboratory experiments. Results indicate that under river conditions, the intake efficiency of the US D-96 sampler is superior to that of the US D-77 bag-type sampler and

  1. An Evaluation of a Human Development Laboratory. A Study of the Outcome and Process of a Laboratory Learning Experience

    DTIC Science & Technology

    1977-08-01

    major emphasis was on the self-understanding of one’s interpersonal behavior and attitudes , and how they impacted on interpersonal relationships. The...in behavior and attitudes related to increased interpersonal effectiveness? The second part of the study focuses on the relationship of specific 22...process measures are discussed below. Outcome Measurement Two basic instruments were used to assess change from pre-laboratory attitudes and behavior

  2. Monitoring CCS Sites: Lessons Learned Studying Natural Laboratories.

    NASA Astrophysics Data System (ADS)

    Tartarello, M. C.; Beaubien, S. E.; Graziani, S.; Lombardi, S.; Ruggiero, L.

    2016-12-01

    Monitoring is one of the most important aspects of Carbon Capture and Storage (CCS), both for early recognition of leaks from the reservoir and for public safety. Natural analogues could be useful to understand the potential impact of a leakage on the local ecosystem and to develop new techniques of monitoring. These sites, called also "natural laboratories", are characterized by natural, geologically-produced CO2 constantly leaking from the seafloor or from the groundsurface. In the last 10 years, our group as partner of some EC funded projects focused on CCS (NASCENT (2000-2003), CO2GeoNet (2004-2009), CO2ReMoVe (2006-2011), RISCS (2010-2013), and ECO2 (2011-2015)), studied gas migration mechanisms in these "natural laboratories", applying near-surface geochemistry to monitoring. This method provides one of the most powerful tools to assess whether a CCS site is leaking and, if it is, to quantify that leakage. This is because rather than being a remote method that estimates amounts based on proxy associations, such as some geophysical tools, it is an exact measurement of the item of interest (in this case CO2) in the accessible biosphere where there is concern regarding its potential impact. In particular, we have been studied two sites in Italy, characterized by significant emissions of CO2, related to volcanic emissions: the Latera Caldera (in Central Italy) and the offshore emissions near Panarea Island. We combined continuous and discontinuous monitoring, structural surveys and gas flux measurements. The results show a strong correlation between fault architecture and leakage rates. Moreover, the monitoring of an area for long periods allows defining the baseline, which is the fluctuation of gas concentrations both spatially and temporally as a function of biological, chemical, geological, land-use and meteorological processes.

  3. NETL Extreme Drilling Laboratory Studies High Pressure High Temperature Drilling Phenomena

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lyons, K.D.; Honeygan, S.; Moroz, T

    2007-06-01

    The U.S. Department of Energy’s National Energy Technology Laboratory (NETL) established an Extreme Drilling Lab to engineer effective and efficient drilling technologies viable at depths greater than 20,000 feet. This paper details the challenges of ultra-deep drilling, documents reports of decreased drilling rates as a result of increasing fluid pressure and temperature, and describes NETL’s Research and Development activities. NETL is invested in laboratory-scale physical simulation. Their physical simulator will have capability of circulating drilling fluids at 30,000 psi and 480 °F around a single drill cutter. This simulator will not yet be operational by the planned conference dates; therefore,more » the results will be limited to identification of leading hypotheses of drilling phenomena and NETL’s test plans to validate or refute such theories. Of particular interest to the Extreme Drilling Lab’s studies are the combinatorial effects of drilling fluid pressure, drilling fluid properties, rock properties, pore pressure, and drilling parameters, such as cutter rotational speed, weight on bit, and hydraulics associated with drilling fluid introduction to the rock-cutter interface. A detailed discussion of how each variable is controlled in a laboratory setting will be part of the conference paper and presentation.« less

  4. Anthropometric measures in cardiovascular disease prediction: comparison of laboratory-based versus non-laboratory-based model.

    PubMed

    Dhana, Klodian; Ikram, M Arfan; Hofman, Albert; Franco, Oscar H; Kavousi, Maryam

    2015-03-01

    Body mass index (BMI) has been used to simplify cardiovascular risk prediction models by substituting total cholesterol and high-density lipoprotein cholesterol. In the elderly, the ability of BMI as a predictor of cardiovascular disease (CVD) declines. We aimed to find the most predictive anthropometric measure for CVD risk to construct a non-laboratory-based model and to compare it with the model including laboratory measurements. The study included 2675 women and 1902 men aged 55-79 years from the prospective population-based Rotterdam Study. We used Cox proportional hazard regression analysis to evaluate the association of BMI, waist circumference, waist-to-hip ratio and a body shape index (ABSI) with CVD, including coronary heart disease and stroke. The performance of the laboratory-based and non-laboratory-based models was evaluated by studying the discrimination, calibration, correlation and risk agreement. Among men, ABSI was the most informative measure associated with CVD, therefore ABSI was used to construct the non-laboratory-based model. Discrimination of the non-laboratory-based model was not different than laboratory-based model (c-statistic: 0.680-vs-0.683, p=0.71); both models were well calibrated (15.3% observed CVD risk vs 16.9% and 17.0% predicted CVD risks by the non-laboratory-based and laboratory-based models, respectively) and Spearman rank correlation and the agreement between non-laboratory-based and laboratory-based models were 0.89 and 91.7%, respectively. Among women, none of the anthropometric measures were independently associated with CVD. Among middle-aged and elderly where the ability of BMI to predict CVD declines, the non-laboratory-based model, based on ABSI, could predict CVD risk as accurately as the laboratory-based model among men. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  5. Laboratory Instructions and Study Guide for Human Anatomy. Part Two, Fourth Edition.

    ERIC Educational Resources Information Center

    Conrey, Kathleen

    During the process of studying the specific course content of human anatomy, students are being educated to expand their vocabulary, learn to deal successfully with complex tasks, and use a specific way of thinking. This is the second volume in a set of laboratory instructions and study notes which are designed to accompany a lecture series in…

  6. Laboratory Instructions and Study Guide for Human Anatomy. Part One, Fourth Edition.

    ERIC Educational Resources Information Center

    Conrey, Kathleen

    During the process of studying the specific course content of human anatomy, students are being educated to expand their vocabulary, deal successfully with complex tasks, and use a specific way of thinking. This is the first volume in a set of laboratory instructions and study notes which are designed to accompany a lecture series in human…

  7. Hydrodynamic Mediation of Killifish Predation on Infaunal Polychaetes

    NASA Astrophysics Data System (ADS)

    Hentschel, B. T.; Hayman, N. T.; Anderson, T. W.

    2016-02-01

    To explore predator-prey interactions between California killifish (Fundulus parvipinnis) and spionid polychaetes (Polydora cornuta and Streblospio benedicti) in tidal creeks, we conducted a laboratory flume experiment to quantify whether killifish prey-patch selectivity varies with flow speed. The flume included a 300-cm2 area of defaunated sediment within which we centrally positioned 24 P. cornuta, 24 S. benedicti, or no worms as a prey-free control. We videotaped groups of three killifish for 50 min at one of six unidirectional flow speeds (3, 6, 9, 12, 15, or 18 cm/s measured 1.5 cm above bottom) and recorded their bite rate anywhere in the sediment area vs. bites directed at the central prey patch (98 cm2). Each flow speed and prey treatment was replicated by four independent flume runs (i.e., 72 total flume runs). The percentage of bites directed at the central patch varied significantly with flow speed and worm presence. With defaunated sediment only, 33% of bites were directed at the central patch at all flow speeds, consistent with a null model of non-selective foraging. When either worm species inhabited the central patch, 65% of bites were directed at the central patch at 3 and 6 cm/s, and patch selectivity declined linearly as flow increased. Despite differences in morphology and behavior, the two prey species elicited similar foraging activity by killifish. We pooled the P. cornuta and S. benedicti treatments to determine the flow speed at which prey-patch selectivity by killifish became statistically indistinguishable from non-selective biting in the absence of prey. At flow speeds of 3, 6, and 9 cm/s, the percentage of bites located in the 98-cm2 patch was significantly greater when live worms were present compared to the prey-free controls. At 12, 15, and 18 cm/s, there was not a significant difference between the control patches and those containing live worms, indicating 12 cm/s is a flow threshold above which killifish cannot selectively forage

  8. Investigating Student Perceptions of the Chemistry Laboratory and Their Approaches to Learning in the Laboratory

    NASA Astrophysics Data System (ADS)

    Berger, Spencer Granett

    This dissertation explores student perceptions of the instructional chemistry laboratory and the approaches students take when learning in the laboratory environment. To measure student perceptions of the chemistry laboratory, a survey instrument was developed. 413 students responded to the survey during the Fall 2011 semester. Students' perception of the usefulness of the laboratory in helping them learn chemistry in high school was related to several factors regarding their experiences in high school chemistry. Students' perception of the usefulness of the laboratory in helping them learn chemistry in college was also measured. Reasons students provided for the usefulness of the laboratory were categorized. To characterize approaches to learning in the laboratory, students were interviewed midway through semester (N=18). The interviews were used to create a framework describing learning approaches that students use in the laboratory environment. Students were categorized into three levels: students who view the laboratory as a requirement, students who believe that the laboratory augments their understanding, and students who view the laboratory as an important part of science. These categories describe the types of strategies students used when conducting experiments. To further explore the relationship between students' perception of the laboratory and their approaches to learning, two case studies are described. These case studies involve interviews in the beginning and end of the semester. In the interviews, students reflect on what they have learned in the laboratory and describe their perceptions of the laboratory environment. In order to encourage students to adopt higher-level approaches to learning in the laboratory, a metacognitive intervention was created. The intervention involved supplementary questions that students would answer while completing laboratory experiments. The questions were designed to encourage students to think critically about the

  9. Quality Assessment of Urinary Stone Analysis: Results of a Multicenter Study of Laboratories in Europe

    PubMed Central

    Siener, Roswitha; Buchholz, Noor; Daudon, Michel; Hess, Bernhard; Knoll, Thomas; Osther, Palle J.; Reis-Santos, José; Sarica, Kemal; Traxer, Olivier; Trinchieri, Alberto

    2016-01-01

    After stone removal, accurate analysis of urinary stone composition is the most crucial laboratory diagnostic procedure for the treatment and recurrence prevention in the stone-forming patient. The most common techniques for routine analysis of stones are infrared spectroscopy, X-ray diffraction and chemical analysis. The aim of the present study was to assess the quality of urinary stone analysis of laboratories in Europe. Nine laboratories from eight European countries participated in six quality control surveys for urinary calculi analyses of the Reference Institute for Bioanalytics, Bonn, Germany, between 2010 and 2014. Each participant received the same blinded test samples for stone analysis. A total of 24 samples, comprising pure substances and mixtures of two or three components, were analysed. The evaluation of the quality of the laboratory in the present study was based on the attainment of 75% of the maximum total points, i.e. 99 points. The methods of stone analysis used were infrared spectroscopy (n = 7), chemical analysis (n = 1) and X-ray diffraction (n = 1). In the present study only 56% of the laboratories, four using infrared spectroscopy and one using X-ray diffraction, fulfilled the quality requirements. According to the current standard, chemical analysis is considered to be insufficient for stone analysis, whereas infrared spectroscopy or X-ray diffraction is mandatory. However, the poor results of infrared spectroscopy highlight the importance of equipment, reference spectra and qualification of the staff for an accurate analysis of stone composition. Regular quality control is essential in carrying out routine stone analysis. PMID:27248840

  10. Quality Assessment of Urinary Stone Analysis: Results of a Multicenter Study of Laboratories in Europe.

    PubMed

    Siener, Roswitha; Buchholz, Noor; Daudon, Michel; Hess, Bernhard; Knoll, Thomas; Osther, Palle J; Reis-Santos, José; Sarica, Kemal; Traxer, Olivier; Trinchieri, Alberto

    2016-01-01

    After stone removal, accurate analysis of urinary stone composition is the most crucial laboratory diagnostic procedure for the treatment and recurrence prevention in the stone-forming patient. The most common techniques for routine analysis of stones are infrared spectroscopy, X-ray diffraction and chemical analysis. The aim of the present study was to assess the quality of urinary stone analysis of laboratories in Europe. Nine laboratories from eight European countries participated in six quality control surveys for urinary calculi analyses of the Reference Institute for Bioanalytics, Bonn, Germany, between 2010 and 2014. Each participant received the same blinded test samples for stone analysis. A total of 24 samples, comprising pure substances and mixtures of two or three components, were analysed. The evaluation of the quality of the laboratory in the present study was based on the attainment of 75% of the maximum total points, i.e. 99 points. The methods of stone analysis used were infrared spectroscopy (n = 7), chemical analysis (n = 1) and X-ray diffraction (n = 1). In the present study only 56% of the laboratories, four using infrared spectroscopy and one using X-ray diffraction, fulfilled the quality requirements. According to the current standard, chemical analysis is considered to be insufficient for stone analysis, whereas infrared spectroscopy or X-ray diffraction is mandatory. However, the poor results of infrared spectroscopy highlight the importance of equipment, reference spectra and qualification of the staff for an accurate analysis of stone composition. Regular quality control is essential in carrying out routine stone analysis.

  11. Service quality framework for clinical laboratories.

    PubMed

    Ramessur, Vinaysing; Hurreeram, Dinesh Kumar; Maistry, Kaylasson

    2015-01-01

    The purpose of this paper is to illustrate a service quality framework that enhances service delivery in clinical laboratories by gauging medical practitioner satisfaction and by providing avenues for continuous improvement. The case study method has been used for conducting the exploratory study, with focus on the Mauritian public clinical laboratory. A structured questionnaire based on the SERVQUAL service quality model was used for data collection, analysis and for the development of the service quality framework. The study confirms the pertinence of the following service quality dimensions within the context of clinical laboratories: tangibility, reliability, responsiveness, turnaround time, technology, test reports, communication and laboratory staff attitude and behaviour. The service quality framework developed, termed LabSERV, is vital for clinical laboratories in the search for improving service delivery to medical practitioners. This is a pioneering work carried out in the clinical laboratory sector in Mauritius. Medical practitioner expectations and perceptions have been simultaneously considered to generate a novel service quality framework for clinical laboratories.

  12. A Laboratory Experiment on the Evolution of a Sand Gravel Reach Under a Lack of Sediment Supply

    NASA Astrophysics Data System (ADS)

    Orru, C.; Chavarrias, V.; Ferrara, V.; Blom, A.

    2014-12-01

    A flume experiment was conducted to examine the evolution of a sand-gravel reach under a lack of sediment supply. The experimental data are used to validate a numerical sand-gravel model. A bed composed of a bi-modal sediment mixture is installed with a uniform slope and an imposed gradual fining pattern. Initially, the sand fraction gradually increases in streamwise direction until the bed is fully composed of sand. The water discharge and downstream water level were constant, and the sediment feed rate was equal to zero. The experiment was dominated by bed load, partial transport, and a subcritical flow regime was imposed. The flow rate was such that only sand was mobile (partial transport), which led to a coarsening over the upstream reach and a gradual reduction of the sediment transport rate during the experiment. New equipment was used to measure the evolution of the grain size distribution of the bed surface during the experiment over the entire flume using image analysis. In the upstream reach we observed a gradual coarsening over time and the formation of an armour layer, which resulted in a more abrupt transition in grain size of the bed surface. Bed degradation increased in streamwise direction. This is due to the initial streamwise increase in the availability of sand in the bed. The different volume fraction content of sand in the bed allowed for the gravel to sink more in the downstream part of the upstream reach. The sand reach suffered from a larger degradation. Finally, we see one reach dominated by sand, small bedforms, and a small bed slope, and a gravel reach dominated by a larger bed slope.

  13. Influence of study approaches and course design on academic success in the undergraduate anatomy laboratory.

    PubMed

    Eleazer, Courtney D; Scopa Kelso, Rebecca

    2018-01-04

    Many pre-health professional programs require completion of an undergraduate anatomy course with a laboratory component, yet grades in these courses are often low. Many students perceive anatomy as a more challenging subject than other coursework, and the resulting anxiety surrounding this perception may be a significant contributor to poor performance. Well-planned and deliberate guidance from instructors, as well as thoughtful course design, may be necessary to assist students in finding the best approach to studying for anatomy. This article assesses which study habits are associated with course success and whether course design influences study habits. Surveys (n = 1,274) were administered to students enrolled in three undergraduate human anatomy laboratory courses with varying levels of cooperative learning and structured guidance. The surveys collected information on potential predictors of performance, including student demographics, educational background, self-assessment ability, and study methods (e.g., flashcards, textbooks, diagrams). Compared to low performers, high performers perceive studying in laboratory, asking the instructor questions, quizzing alone, and quizzing others as more effective for learning. Additionally, students co-enrolled in a flipped, active lecture anatomy course achieve higher grades and find active learning activities (e.g., quizzing alone and in groups) more helpful for their learning in the laboratory. These results strengthen previous research suggesting that student performance is more greatly enhanced by an active classroom environment that practices successful study strategies rather than one that simply encourages students to employ such strategies inside and outside the classroom. Anat Sci Educ. © 2018 American Association of Anatomists. © 2018 American Association of Anatomists.

  14. Addressing the key communication barriers between microbiology laboratories and clinical units: a qualitative study.

    PubMed

    Skodvin, Brita; Aase, Karina; Brekken, Anita Løvås; Charani, Esmita; Lindemann, Paul Christoffer; Smith, Ingrid

    2017-09-01

    Many countries are on the brink of establishing antibiotic stewardship programmes in hospitals nationwide. In a previous study we found that communication between microbiology laboratories and clinical units is a barrier to implementing efficient antibiotic stewardship programmes in Norway. We have now addressed the key communication barriers between microbiology laboratories and clinical units from a laboratory point of view. Qualitative semi-structured interviews were conducted with 18 employees (managers, doctors and technicians) from six diverse Norwegian microbiological laboratories, representing all four regional health authorities. Interviews were recorded and transcribed verbatim. Thematic analysis was applied, identifying emergent themes, subthemes and corresponding descriptions. The main barrier to communication is disruption involving specimen logistics, information on request forms, verbal reporting of test results and information transfer between poorly integrated IT systems. Furthermore, communication is challenged by lack of insight into each other's area of expertise and limited provision of laboratory services, leading to prolonged turnaround time, limited advisory services and restricted opening hours. Communication between microbiology laboratories and clinical units can be improved by a review of testing processes, educational programmes to increase insights into the other's area of expertise, an evaluation of work tasks and expansion of rapid and point-of-care test services. Antibiotic stewardship programmes may serve as a valuable framework to establish these measures. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.

  15. The Development and Evaluation of Industrial Case Studies to Support a New Laboratory Course in Electrical Engineering.

    ERIC Educational Resources Information Center

    Bolton, B.; Adderley, K. J.

    1978-01-01

    After viewing videotaped case studies indicating the relevance of electrical laboratory work to professional engineers, student attitudes showed a positive improvement toward laboratory work. Semantic differential tests, questionnaires, and interviews were used. (Author/MH)

  16. Development and testing of highway storm-sewer flow measurement and recording system

    USGS Publications Warehouse

    Kilpatrick, F.A.; Kaehrle, W.R.; Hardee, Jack; Cordes, E.H.; Landers, M.N.

    1985-01-01

    A comprehensive study and development of measuring instruments and techniques for measuring all components of flow in a storm-sewer drainage system was undertaken by the U.S. Geological Survey under the sponsorship of the Federal Highway Administration. The study involved laboratory and field calibration and testing of measuring flumes, pipe insert meters, weirs, electromagnetic velocity meters as well as the development and calibration of pneumatic-bubbler pressure transducer head measuring systems. Tracer-dilution and acoustic flow meter measurements were used in field verification tests. A single micrologger was used to record data from all the above instruments as well as from a tipping-bucket rain gage and also to activate on command the electromagnetic velocity meter and tracer-dilution systems. (Author 's abstract)

  17. How compliant are technicians with universal safety measures in medical laboratories in Croatia?--A pilot study.

    PubMed

    Dukic, Kristina; Zoric, Matea; Pozaic, Petra; Starcic, Jelena; Culjak, Marija; Saracevic, Andrea; Miler, Marijana

    2015-01-01

    This pilot study aimed to investigate the use of personal protective equipment (PPE) and compliance to the code of conduct (rules defined in institutional, governmental and professional guidelines) among laboratory technicians in Croatian medical laboratories. In addition, we explored the differences in compliance between participants of different age groups, laboratory ownership and accreditation status. An anonymous and voluntary survey with 15 questions was conducted among Croatian medical laboratory technicians (N=217). The questions were divided into two groups: demographic characteristics and the use of PPE. The questions of the second part were graded according to the Likert scale (1-4) and an overall score, shown as median and range (min-max), was calculated for each participant. Differences between the overall scores were tested for each group of participants. The majority of participants always wear protective clothes at work, 38.7% of them always wear gloves in daily routine, more than 30.0% consume food and almost half of them drink beverages at workplace. A significantly lower overall score was found for participants working in public compared to private laboratories (36 (16-40) vs. 40 (31-40), P<0.001). There were no statistically significant differences in overall scores for participants of different age groups (P=0.456) and laboratory accreditation status (P=0.081). A considerable percentage of laboratory technicians in Croatian medical laboratories do not comply with safety measures. Lack of compliance is observed in all personnel regardless laboratory accreditation and participants' age. However, those working in private laboratories adhere more to the code of conduct.

  18. An Electronics "Unit Laboratory"

    ERIC Educational Resources Information Center

    Davies, E. R.; Penton, S. J.

    1976-01-01

    Describes a laboratory teaching technique in which a single topic (in this case, bipolar junction transistors) is studied over a period of weeks under the supervision of one staff member, who also designs the laboratory work. (MLH)

  19. Fred Hutchinson Cancer Research Center, Seattle, Washington: Laboratories for the 21st Century Case Studies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    2001-12-01

    This case study was prepared by participants in the Laboratories for the 21st Century program, a joint endeavor of the U.S. Environmental Protection Agency and the U.S. Department of Energy's Federal Energy Management Program. The goal of this program is to foster greater energy efficiency in new laboratory buildings for both the public and the private sectors. Retrofits of existing laboratories are also encouraged. The energy-efficient features of the laboratories in the Fred Hutchinson Cancer Research Center complex in Seattle, Washington, include extensive use of efficient lighting, variable-air-volume controls, variable-speed drives, motion sensors, and high-efficiency chillers and motors. With aboutmore » 532,000 gross square feet, the complex is estimated to use 33% less electrical energy than most traditional research facilities consume because of its energy-efficient design and features.« less

  20. Assessing Clinical Laboratory Quality: A College of American Pathologists Q-Probes Study of Prothrombin Time INR Structures, Processes, and Outcomes in 98 Laboratories.

    PubMed

    Howanitz, Peter J; Darcy, Theresa P; Meier, Frederick A; Bashleben, Christine P

    2015-09-01

    The anticoagulant warfarin has been identified as the second most frequent drug responsible for serious, disabling, and fatal adverse drug events in the United States, and its effect on blood coagulation is monitored by the laboratory test called international normalized ratio (INR). To determine the presence of INR policies and procedures, INR practices, and completeness and timeliness of reporting critical INR results in participants' clinical laboratories. Participants reviewed their INR policies and procedure requirements, identified their practices by using a questionnaire, and studied completeness of documentation and timeliness of reporting critical value INR results for outpatients and emergency department patients. In 98 participating institutions, the 5 required policies and procedures were in place in 93% to 99% of clinical laboratories. Fifteen options for the allowable variations among duplicate results from different analyzers, 12 different timeliness goals for reporting critical values, and 18 unique critical value limits were used by participants. All required documentation elements were present in 94.8% of 192 reviewed INR validation reports. Critical value INR results were reported within the time frame established by the laboratory for 93.4% of 2604 results, but 1.0% of results were not reported. Although the median laboratories successfully communicated all critical results within their established time frames and had all the required validation elements based in their 2 most recent INR calculations, those participants at the lowest 10th percentile were successful in 80.0% and 85.7% of these requirements, respectively. Significant opportunities exist for adherence to INR procedural requirements and for practice patterns and timeliness goals for INR critical results' reporting.

  1. Towards the development of laboratory methods for studying drinking games: Initial findings, methodological considerations, and future directions

    PubMed Central

    Silvestri, Mark M.; Lewis, Jennifer M.; Borsari, Brian; Correia, Christopher J.

    2014-01-01

    Background Drinking games are prevalent among college students and are associated with increased alcohol use and negative alcohol-related consequences. There has been substantial growth in research on drinking games. However, the majority of published studies rely on retrospective self-reports of behavior and very few studies have made use of laboratory procedures to systematically observe drinking game behavior. Objectives The current paper draws on the authors’ experiences designing and implementing methods for the study of drinking games in the laboratory. Results The paper addressed the following key design features: (a) drinking game selection; (b) beverage selection; (c) standardizing game play; (d) selection of dependent and independent variables; and (e) creating a realistic drinking game environment. Conclusions The goal of this methodological review paper is to encourage other researchers to pursue laboratory research on drinking game behavior. Use of laboratory-based methodologies will facilitate a better understanding of the dynamics of risky drinking and inform prevention and intervention efforts. PMID:25192209

  2. Fire vs. Metal: A Laboratory Study Demonstrating Microbial Responses to Soil Disturbances

    ERIC Educational Resources Information Center

    Stromberger, Mary E.

    2005-01-01

    Incubation studies are traditionally used in soil microbiology laboratory classes to demonstrate microbial respiration and N mineralization-immobilization processes. Sometimes these exercises are done to calculate a N balance in N fertilizer-amended soils. However, examining microbial responses to environmental perturbations would appeal to soil…

  3. Design of laboratory experiments to study radiation-driven implosions

    DOE PAGES

    Keiter, P. A.; Trantham, M.; Malamud, G.; ...

    2017-02-03

    The interstellar medium is heterogeneous with dense clouds amid an ambient medium. Radiation from young OB stars asymmetrically irradiate the dense clouds. Bertoldi (1989) developed analytic formulae to describe possible outcomes of these clouds when irradiated by hot, young stars. One of the critical parameters that determines the cloud’s fate is the number of photon mean free paths in the cloud. For the extreme cases where the cloud size is either much greater than or much less than one mean free path, the radiation transport should be well understood. However, as one transitions between these limits, the radiation transport ismore » much more complex and is a challenge to solve with many of the current radiation transport models implemented in codes. In this paper, we present the design of laboratory experiments that use a thermal source of x-rays to asymmetrically irradiate a low-density plastic foam sphere. The experiment will vary the density and hence the number of mean free paths of the sphere to study the radiation transport in different regimes. Finally, we have developed dimensionless parameters to relate the laboratory experiment to the astrophysical system and we show that we can perform the experiment in the same transport regime.« less

  4. Feasibility study of medical isotope production at Sandia National Laboratories

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Massey, C.D.; Miller, D.L.; Carson, S.D.

    1995-12-01

    In late 1994, Sandia National Laboratories in Albuquerque, New Mexico, (SNL/NM), was instructed by the Department of Energy (DOE) Isotope Production and Distribution Program (IPDP) to examine the feasibility of producing medically useful radioisotopes using the Annular Core Research Reactor (ACRR) and the Hot Cell Facility (HCF). Los Alamos National Laboratory (LANL) would be expected to supply the targets to be irradiated in the ACRR. The intent of DOE would be to provide a capability to satisfy the North American health care system demand for {sup 99}Mo, the parent of {sup 99m}Tc, in the event of an interruption in themore » current Canadian supply. {sup 99m}Tc is used in 70 to 80% of all nuclear medicine procedures in the US. The goal of the SNL/NM study effort is to determine the physical plant capability, infrastructure, and staffing necessary to meet the North American need for {sup 99}Mo and to identify and examine all issues with potential for environmental impact.« less

  5. Modeling of Waves Propagating in Water with a Crushed Ice Layer on the Free Surface

    NASA Astrophysics Data System (ADS)

    Szmidt, Kazimierz

    2017-12-01

    A transformation of gravitational waves in fluid of constant depth with a crushed ice layer floating on the free fluid surface is considered. The propagating waves undergo a slight damping along their path of propagation. The main goal of the study is to construct an approximate descriptive model of this phenomenon.With regard to small displacements of the free surface, a viscous type model of damping is considered, which corresponds to a continuous distribution of dash-pots at the free surface of the fluid. A constant parameter of the dampers is assumed in advance as known parameter of damping. This parameter may be obtained by means of experiments in a laboratory flume.

  6. Effect of Soil Fumigation on Degradation of Pendimethalin and Oxyfluorfen in Laboratory and Ginger Field Studies.

    PubMed

    Huang, Bin; Li, Jun; Fang, Wensheng; Liu, Pengfei; Guo, Meixia; Yan, Dongdong; Wang, Qiuxia; Cao, Aocheng

    2016-11-23

    Herbicides are usually applied to agricultural fields following soil fumigation to provide effective weed control in high-value cash crops. However, phytotoxicity has been observed in ginger seedlings following the application of herbicides in fumigated fields. This study tested a mixture of herbicides (pendimethalin and oxyfluorfen) and several fumigant treatments in laboratory and field studies to determine their effect on the growth of ginger. The results showed that soil fumigation significantly (P < 0.05) extended the degradation period of these herbicides in the field and in laboratory studies. The half-life of pendimethalin was extended by an average of approximately 1.29 times in the field and 1.74 times in the laboratory. The half-life of oxyfluorfen was extended by an average of about 1.19 times in the field and 1.32 times in the laboratory. Moreover, the extended period of herbicide degradation in the fumigant and nonfumigant treatments significantly reduced ginger plant height, leaf number, stem diameter, and the chlorophyll content. The study concluded that applying a dose below the recommended rate of these herbicides in chloropicrin (CP) or CP + 1,3-dichloropropene fumigated ginger fields is appropriate, as application of the recommended herbicide dose in fumigated soil may be phytotoxic to ginger.

  7. Gene Polymorphism Studies in a Teaching Laboratory

    NASA Astrophysics Data System (ADS)

    Shultz, Jeffry

    2009-02-01

    I present a laboratory procedure for illustrating transcription, post-transcriptional modification, gene conservation, and comparative genetics for use in undergraduate biology education. Students are individually assigned genes in a targeted biochemical pathway, for which they design and test polymerase chain reaction (PCR) primers. In this example, students used genes annotated for the steroid biosynthesis pathway in soybean. The authoritative Kyoto encyclopedia of genes and genomes (KEGG) interactive database and other online resources were used to design primers based first on soybean expressed sequence tags (ESTs), then on ESTs from an alternate organism if soybean sequence was unavailable. Students designed a total of 50 gene-based primer pairs (37 soybean, 13 alternative) and tested these for polymorphism state and similarity between two soybean and two pea lines. Student assessment was based on acquisition of laboratory skills and successful project completion. This simple procedure illustrates conservation of genes and is not limited to soybean or pea. Cost per student estimates are included, along with a detailed protocol and flow diagram of the procedure.

  8. Oak Ridge National Laboratory`s (ORNL) ecological and physical science study center: A hands-on science program for K-12 students

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bradshaw, S.P.

    1994-12-31

    In our tenth year of educational service and outreach, Oak Ridge National Laboratory`s Ecological and Physical Science Study Center (EPSSC) provides hands-on, inquiry-based science activities for area students and teachers. Established in 1984, the EPSSC now hosts over 20,000 student visits. Designed to foster a positive attitude towards science, each unit includes activities which reinforce the science concept being explored. Outdoor science units provide field experience at the Department of Energy`s Oak Ridge National Environmental Research Park and outreach programs are offered on-site in area schools. Other programs are offered as extensions of the EPSSC core programs, including on-site studentmore » science camps, all-girl programs, outreach science camps, student competitions, teacher in-service presentations and teacher workshops.« less

  9. Human Laboratory Paradigms in Alcohol Research

    PubMed Central

    Plebani, Jennifer G.; Ray, Lara A.; Morean, Meghan E.; Corbin, William R.; Mackillop, James; Amlung, Michael; King, Andrea C.

    2014-01-01

    Human laboratory studies have a long and rich history in the field of alcoholism. Human laboratory studies have allowed for advances in alcohol research in a variety of ways, including elucidating of the neurobehavioral mechanisms of risk, identifying phenotypically distinct sub-types of alcohol users, investigating of candidate genes underlying experimental phenotypes for alcoholism, and testing mechanisms of action of alcoholism pharmacotherapies on clinically-relevant translational phenotypes, such as persons exhibiting positive-like alcohol effects or alcohol craving. Importantly, the field of human laboratory studies in addiction has progressed rapidly over the past decade and has built upon earlier findings of alcohol's neuropharmacological effects to advancing translational research on alcoholism etiology and treatment. To that end, the new generation of human laboratory studies has focused on applying new methodologies, further refining alcoholism phenotypes, and translating these findings to studies of alcoholism genetics, medication development, and pharmacogenetics. The combination of experimental laboratory approaches with recent developments in neuroscience and pharmacology has been particularly fruitful in furthering our understanding of the impact of individual differences in alcoholism risk and in treatment response. This review of the literature focuses on human laboratory studies of subjective intoxication, alcohol craving, anxiety, and behavioral economics. Each section discusses opportunities for phenotype refinement under laboratory conditions, as well as its application to translational science of alcoholism. A summary and recommendations for future research are also provided. PMID:22309888

  10. Field and Laboratory Studies of Atmospheric Organic Aerosol

    NASA Astrophysics Data System (ADS)

    Coggon, Matthew Mitchell

    This thesis is the culmination of field and laboratory studies aimed at assessing processes that affect the composition and distribution of atmospheric organic aerosol. An emphasis is placed on measurements conducted using compact and high-resolution Aerodyne Aerosol Mass Spectrometers (AMS). The first three chapters summarize results from aircraft campaigns designed to evaluate anthropogenic and biogenic impacts on marine aerosol and clouds off the coast of California. Subsequent chapters describe laboratory studies intended to evaluate gas and particle-phase mechanisms of organic aerosol oxidation. The 2013 Nucleation in California Experiment (NiCE) was a campaign designed to study environments impacted by nucleated and/or freshly formed aerosol particles. Terrestrial biogenic aerosol with > 85% organic mass was observed to reside in the free troposphere above marine stratocumulus. This biogenic organic aerosol (BOA) originated from the Northwestern United States and was transported to the marine atmosphere during periodic cloud-clearing events. Spectra recorded by a cloud condensation nuclei counter demonstrated that BOA is CCN active. BOA enhancements at latitudes north of San Francisco, CA coincided with enhanced cloud water concentrations of organic species such as acetate and formate. Airborne measurements conducted during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE) were aimed at evaluating the contribution of ship emissions to the properties of marine aerosol and clouds off the coast of central California. In one study, analysis of organic aerosol mass spectra during periods of enhanced shipping activity yielded unique tracers indicative of cloud-processed ship emissions (m/z 42 and 99). The variation of their organic fraction (f42 and f 99) was found to coincide with periods of heavy (f 42 > 0.15; f99 > 0.04), moderate (0.05 < f42 < 0.15; 0.01 < f99 < 0.04), and negligible (f42 < 0.05; f99 < 0.01) ship influence. Application of

  11. A Laboratory Study of X-to-Frequency Converters.

    ERIC Educational Resources Information Center

    Kartalopoulos, Stamatios V.

    1979-01-01

    Describes a laboratory demonstration that can be used to convert an analog quantity into frequency, which can then be converted into a binary measure using either an oscilloscope or a frequency counter. (MA)

  12. Wake effect on a uniform flow behind wind-turbine model

    NASA Astrophysics Data System (ADS)

    Okulov, V. L.; Naumov, I. V.; Mikkelsen, R. F.; Sørensen, J. N.

    2015-06-01

    LDA experiments were carried out to study the development of mean velocity profiles of the very far wake behind a wind turbine model in a water flume. The model of the rotor is placed in a middle of the flume. The initial flume flow is subjected to a very low turbulence level, limiting the influence of external disturbances on the development of the inherent wake instability. The rotor is three-bladed and designed using Glauert's optimum theory at a tip speed ratio λ = 5 with a constant of the lift coefficient along the span, CL= 0.8. The wake development has been studied in the range of tip speed ratios from 3 to 9, and at different cross-sections from 10 to 100 rotor radii downstream from the rotor. By using regression techniques to fit the velocity profiles it was possible to obtain accurate velocity deficits and estimate length scales of the wake attenuation. The data are compared with different analytical models for wind turbine wakes.

  13. Laboratory Studies of Larval Cannibalism in ’Toxorhynchites amboinensis’ (Diptera: Culicidae)

    DTIC Science & Technology

    1990-09-01

    1986. However, there have been few laboratory studies Container Volume. Eggs of Tx. amboinensis of the phenomenon. Rubio & Avesta (1984) sug- were...predator ratio and frequency of cannibalism, as competition for food may limit growth. Alterna- proposed by Rubio & Avesta (1984). A careful ex- tively, the

  14. A FMEA clinical laboratory case study: how to make problems and improvements measurable.

    PubMed

    Capunzo, Mario; Cavallo, Pierpaolo; Boccia, Giovanni; Brunetti, Luigi; Pizzuti, Sante

    2004-01-01

    The authors have experimented the application of the Failure Mode and Effect Analysis (FMEA) technique in a clinical laboratory. FMEA technique allows: a) to evaluate and measure the hazards of a process malfunction, b) to decide where to execute improvement actions, and c) to measure the outcome of those actions. A small sample of analytes has been studied: there have been determined the causes of the possible malfunctions of the analytical process, calculating the risk probability index (RPI), with a value between 1 and 1,000. Only for the cases of RPI > 400, improvement actions have been implemented that allowed a reduction of RPI values between 25% to 70% with a costs increment of < 1%. FMEA technique can be applied to the processes of a clinical laboratory, even if of small dimensions, and offers a high potential of improvement. Nevertheless, such activity needs a thorough planning because it is complex, even if the laboratory already operates an ISO 9000 Quality Management System.

  15. Laboratory study of orographic cloud-like flow

    NASA Astrophysics Data System (ADS)

    Singh, Kanwar Nain; Sreenivas, K. R.

    2013-11-01

    Clouds are one of the major sources of uncertainty in climate prediction, listed in ``the most urgent scientific problems requiring attention'' IPCC. Also, convective clouds are of utmost importance to study the dynamics of tropical meteorology and therefore, play a key role in understanding monsoons. The present work is to study the dynamics of orographic clouds. Parameterization of these clouds will help in forecasting the precipitation accurately. Also, one could validate laboratory results from our study by actually measuring cloud development along a sloping terrain. In this context a planar buoyant turbulent wall jet is considered as an appropriate low order fluid-dynamical model for studying the turbulence and entrainment in orographic-clouds. Flow is volumetrically heated to mimic the latent heat release due to condensation in an actual cloud. This is the first step in studying the entrainment dynamics of the evolving orographic cloud. We are going to present some results on the cloud development using techniques that allows us to construct a 3-dimensional flow field at each instance and its development over the time. By combining velocity field from PIV and flow volume from PLIF at successive instances, we estimate the entrainment coefficient. Since the life-cycle of a cloud is determined by the entrainment of ambient air, these results could be extremely helpful in understanding the dynamics of the clouds. Detailed results will be presented at the conference.

  16. Laboratory Characteristics in Technical Education.

    ERIC Educational Resources Information Center

    Ives, Quay D.

    The research reported is intended to provide a body of information on technical-scientific shop and laboratory education in the field of technological education. The study seeks to address the dearth of organized information on the utilization of laboratories in the technical education context. Various programs involving use of laboratories are…

  17. Laboratory grown subaerial biofilms on granite: application to the study of bioreceptivity.

    PubMed

    Vázquez-Nion, Daniel; Silva, Benita; Troiano, Federica; Prieto, Beatriz

    2017-01-01

    Simulated environmental colonisation of granite was induced under laboratory conditions in order to develop an experimental protocol for studying bioreceptivity. The experimental set-up proved suitable for producing subaerial biofilms by inoculating granite blocks with planktonic multi-species phototrophic cultures derived from natural biofilms. The ability of four different cultures to form biofilms was monitored over a three-month growth period via colour measurements, quantification of photosynthetic pigments and EPS, and CLSM observations. One of the cultures under study, which comprised several taxa including Bryophyta, Charophyta, Chlorophyta and Cyanobacteria, was particularly suitable as an inoculum, mainly because of its microbial richness, its rapid adaptability to the substratum and its high colonisation capacity. The use of this culture as an inoculum in the proposed experimental set-up to produce subaerial biofilms under laboratory conditions will contribute to standardising the protocols involved, thus enabling more objective assessment of the bioreceptivity of granite in further experiments.

  18. Baccalaureate nursing students' perspectives of peer tutoring in simulation laboratory, a Q methodology study.

    PubMed

    Li, Ting; Petrini, Marcia A; Stone, Teresa E

    2018-02-01

    The study aim was to identify the perceived perspectives of baccalaureate nursing students toward the peer tutoring in the simulation laboratory. Insight into the nursing students' experiences and baseline data related to their perception of peer tutoring will assist to improve nursing education. Q methodology was applied to explore the students' perspectives of peer tutoring in the simulation laboratory. A convenience P-sample of 40 baccalaureate nursing students was used. Fifty-eight selected Q statements from each participant were classified into the shape of a normal distribution using an 11-point bipolar scale form with a range from -5 to +5. PQ Method software analyzed the collected data. Three discrete factors emerged: Factor I ("Facilitate or empower" knowledge acquisition), Factor II ("Safety Net" Support environment), and Factor III ("Mentoring" learn how to learn). The findings of this study support and indicate that peer tutoring is an effective supplementary strategy to promote baccalaureate students' knowledge acquisition, establishing a supportive safety net and facilitating their abilities to learn in the simulation laboratory. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Cognitive Responses to Mass Communication: Results from Laboratory Studies and a Field Experiment.

    ERIC Educational Resources Information Center

    Ward, Scott; Ray, Michael L.

    This paper examines some of the cognitive responses people experience while attending to messages. Two laboratory studies and a field experiment were conducted. In the lab studies, three different audience groups (junior and senior high school students and parents) were shown three different anti-drug abuse messages. Various levels of audio…

  20. Anisotropic Rotational Diffusion Studied by Nuclear Spin Relaxation and Molecular Dynamics Simulation: An Undergraduate Physical Chemistry Laboratory

    ERIC Educational Resources Information Center

    Fuson, Michael M.

    2017-01-01

    Laboratories studying the anisotropic rotational diffusion of bromobenzene using nuclear spin relaxation and molecular dynamics simulations are described. For many undergraduates, visualizing molecular motion is challenging. Undergraduates rarely encounter laboratories that directly assess molecular motion, and so the concept remains an…

  1. SENIORLAB: a prospective observational study investigating laboratory parameters and their reference intervals in the elderly.

    PubMed

    Risch, Martin; Nydegger, Urs; Risch, Lorenz

    2017-01-01

    In clinical practice, laboratory results are often important for making diagnostic, therapeutic, and prognostic decisions. Interpreting individual results relies on accurate reference intervals and decision limits. Despite the considerable amount of resources in clinical medicine spent on elderly patients, accurate reference intervals for the elderly are rarely available. The SENIORLAB study set out to determine reference intervals in the elderly by investigating a large variety of laboratory parameters in clinical chemistry, hematology, and immunology. The SENIORLAB study is an observational, prospective cohort study. Subjectively healthy residents of Switzerland aged 60 years and older were included for baseline examination (n = 1467), where anthropometric measurements were taken, medical history was reviewed, and a fasting blood sample was drawn under optimal preanalytical conditions. More than 110 laboratory parameters were measured, and a biobank was set up. The study participants are followed up every 3 to 5 years for quality of life, morbidity, and mortality. The primary aim is to evaluate different laboratory parameters at age-related reference intervals. The secondary aims of this study include the following: identify associations between different parameters, identify diagnostic characteristics to diagnose different circumstances, identify the prevalence of occult disease in subjectively healthy individuals, and identify the prognostic factors for the investigated outcomes, including mortality. To obtain better grounds to justify clinical decisions, specific reference intervals for laboratory parameters of the elderly are needed. Reference intervals are obtained from healthy individuals. A major obstacle when obtaining reference intervals in the elderly is the definition of health in seniors because individuals without any medical condition and any medication are rare in older adulthood. Reference intervals obtained from such individuals cannot be

  2. Physical Sciences Laboratory 1 Rooftop Stack Mixing Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Flaherty, Julia E.; Antonio, Ernest J.

    To address concerns about worker exposures on the Physical Science Laboratory (PSL) rooftop, a tracer study was conducted to measure gaseous tracer concentrations downwind of six stacks on the southern half of the PSL building (PSL-1). These concerns were raised, in part, due to the non-standard configuration of the stacks on this building. Five of the six stacks were only about 8 feet tall, with one shorter stack that was essentially level with the roof deck. These stacks were reconfigured in August 2016, and these exhaust points on PSL-1 are now 18 feet tall. This report describes the objectives ofmore » the tracer tests performed on PSL-1, provides an overview of how the tests were executed, and presents results of the tests. The tests on the PSL rooftop were a follow-on project from a similar study performed on the LSL-II ventilation exhaust (Flaherty and Antonio, 2016).« less

  3. Laboratory study of effects of sonic boom shaping on subjective loudness and acceptability

    NASA Technical Reports Server (NTRS)

    Leatherwood, Jack D.; Sullivan, Brenda M.

    1992-01-01

    A laboratory study was conducted to determine the effects of sonic boom signature shaping on subjective loudness and acceptability. The study utilized the sonic boom simulator at the Langley Research Center. A wide range of symmetrical, front-shock-minimized signature shapes were investigated together with a limited number of asymmetrical signatures. Subjective loudness judgments were obtained from 60 test subjects by using an 11-point numerical category scale. Acceptability judgments were obtained using the method of constant stimuli. Results were used to assess the relative predictive ability of several noise metrics, determine the loudness benefits of detailed boom shaping, and derive laboratory sonic boom acceptability criteria. These results indicated that the A-weighted sound exposure level, the Stevens Mark 7 Perceived Level, and the Zwicker Loudness Level metrics all performed well. Significant reductions in loudness were obtained by increasing front-shock rise time and/or decreasing front-shock overpressure of the front-shock minimized signatures. In addition, the asymmetrical signatures were rated to be slightly quieter than the symmetrical front-shock-minimized signatures of equal A-weighted sound exposure level. However, this result was based on a limited number of asymmetric signatures. The comparison of laboratory acceptability results with acceptability data obtained in more realistic situations also indicated good agreement.

  4. Vermicomposting of winery wastes: a laboratory study.

    PubMed

    Nogales, Rogelio; Cifuentes, Celia; Benítez, Emilio

    2005-01-01

    In Mediterranean countries, millions of tons of wastes from viticulture and winery industries are produced every year. This study describes the ability of the earthworm Eisenia andrei to compost different winery wastes (spent grape marc, vinasse biosolids, lees cakes, and vine shoots) into valuable agricultural products. The evolution of earthworm biomass and enzyme activities was tracked for 16 weeks of vermicomposting, on a laboratory scale. Increases in earthworm biomass for all winery wastes proved lower than in manure. Changes in hydrolytic enzymes and overall microbial activities during the vermicomposting process indicated the biodegradation of the winery wastes. Vermicomposting improved the agronomic value of the winery wastes by reducing the C:N ratio, conductivity and phytotoxicity, while increasing the humic materials, nutrient contents, and pH in all cases. Thus, winery wastes show potential as raw substrates in vermicomposting, although further research is needed to evaluate the feasibility of such wastes in large-scale vermicomposting systems.

  5. Laboratory Spectroscopy of Large Carbon Molecules and Ions in Support of Space Missions. A New Generation of Laboratory & Space Studies

    NASA Technical Reports Server (NTRS)

    Salama, Farid; Tan, Xiaofeng; Cami, Jan; Biennier, Ludovic; Remy, Jerome

    2006-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. A long-standing and major challenge for laboratory astrophysics has been to measure the spectra of large carbon molecules in laboratory environments that mimic (in a realistic way) the physical conditions that are associated with the interstellar emission and absorption regions [1]. This objective has been identified as one of the critical Laboratory Astrophysics objectives to optimize the data return from space missions [2]. An extensive laboratory program has been developed to assess the properties of PAHs in such environments and to describe how they influence the radiation and energy balance in space. We present and discuss the gas-phase electronic absorption spectra of neutral and ionized PAHs measured in the UV-Visible-NIR range in astrophysically relevant environments and discuss the implications for astrophysics [1]. The harsh physical conditions of the interstellar medium characterized by a low temperature, an absence of collisions and strong VUV radiation fields - have been simulated in the laboratory by associating a pulsed cavity ringdown spectrometer (CRDS) with a supersonic slit jet seeded with PAHs and an ionizing, penning-type, electronic discharge. We have measured for the {\\it first time} the spectra of a series of neutral [3,4] and ionized [5,6] interstellar PAHs analogs in the laboratory. An effort has also been attempted to quantify the mechanisms of ion and carbon nanoparticles production in the free jet expansion and to model our simulation of the diffuse interstellar medium in the laboratory [7]. These experiments provide {\\it unique} information on the spectra of free, large carbon-containing molecules and ions in the gas phase. We are now, for the first time, in the position to directly compare laboratory spectral data on free, cold, PAH ions and carbon nano-sized carbon particles with astronomical observations in the

  6. An inter-laboratory comparison study of the ANSI/BIFMA standard test method M7.1 for furniture

    EPA Science Inventory

    Five laboratories using five different test chambers participated in the study to quantify within- and between-laboratory variability in the measurement of emissions of volatile organic compounds (VOCs) from new commercial furniture test items following ANSI/BIFMA M7.1. Test item...

  7. Portuguese Family Physicians’ Awareness of Diagnostic and Laboratory Test Costs: A Cross-Sectional Study

    PubMed Central

    Sá, Luísa; Costa-Santos, Cristina; Teixeira, Andreia; Couto, Luciana; Costa-Pereira, Altamiro; Hespanhol, Alberto; Santos, Paulo; Martins, Carlos

    2015-01-01

    Background Physicians’ ability to make cost-effective decisions has been shown to be affected by their knowledge of health care costs. This study assessed whether Portuguese family physicians are aware of the costs of the most frequently prescribed diagnostic and laboratory tests. Methods A cross-sectional study was conducted in a representative sample of Portuguese family physicians, using computer-assisted telephone interviews for data collection. A Likert scale was used to assess physician’s level of agreement with four statements about health care costs. Family physicians were also asked to estimate the costs of diagnostic and laboratory tests. Each physician’s cost estimate was compared with the true cost and the absolute error was calculated. Results One-quarter (24%; 95% confidence interval: 23%–25%) of all cost estimates were accurate to within 25% of the true cost, with 55% (95% IC: 53–56) overestimating and 21% (95% IC: 20–22) underestimating the true actual cost. The majority (76%) of family physicians thought they did not have or were uncertain as to whether they had adequate knowledge of diagnostic and laboratory test costs, and only 7% reported receiving adequate education. The majority of the family physicians (82%) said that they had adequate access to information about the diagnostic and laboratory test costs. Thirty-three percent thought that costs did not influence their decision to order tests, while 27% were uncertain. Conclusions Portuguese family physicians have limited awareness of diagnostic and laboratory test costs, and our results demonstrate a need for improved education in this area. Further research should focus on identifying whether interventions in cost knowledge actually change ordering behavior, in identifying optimal methods to disseminate cost information, and on improving the cost-effectiveness of care. PMID:26356625

  8. DESIGN OF A SURFACTANT REMEDIATION FIELD DEMONSTRATION BASED ON LABORATORY AND MODELINE STUDIES

    EPA Science Inventory

    Surfactant-enhanced subsurface remediation is being evaluated as an innovative technology for expediting ground-water remediation. This paper reports on laboratory and modeling studies conducted in preparation for a pilot-scale field test of surfactant-enhanced subsurface remedia...

  9. 21 CFR 58.49 - Laboratory operation areas.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Laboratory operation areas. 58.49 Section 58.49... LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Facilities § 58.49 Laboratory operation areas. Separate laboratory space shall be provided, as needed, for the performance of the routine and specialized...

  10. Insights into organic carbon oxidation potential during fluvial transport from laboratory and field experiments

    NASA Astrophysics Data System (ADS)

    Scheingross, J. S.; Dellinger, M.; Eglinton, T. I.; Fuchs, M. C.; Golombek, N.; Hilton, R. G.; Hovius, N.; Lupker, M.; Repasch, M. N.; Sachse, D.; Turowski, J. M.; Vieth-Hillebrand, A.; Wittmann, H.

    2017-12-01

    Over geologic timescales, the exchange of organic carbon (OC) between the atmosphere, hydropshere, biosphere and geosphere can be a major control on atmospheric carbon dioxide concentrations. The carbon fluxes from the oxidation of rock-derived OC (a CO2 source) and erosion, transport, and burial of biospheric OC (a potential CO2 sink) during fluvial transit are approximately the same order of magnitude or larger than those from silicate weathering. Despite field data showing increasing oxidation of OC moving downstream in lowland rivers, it is unclear if losses occur primarily during active fluvial transport, where OC is in continual motion within an aerated river, or during periods of temporary storage in river floodplains which may be anoxic. The unknown location of OC oxidation (i.e., river vs. floodplain) limits our ability to mechanistically link geochemical and geomorphic processes which are required to develop models capable of predicting OC losses, constrain carbon budgets, and unravel links between climate, tectonics, and erosion. To fill this knowledge gap, we investigated OC oxidation in controlled laboratory experiments and a simplified field setting. We performed experiments in annular flumes that simulate fluvial transport without floodplain storage, allowing mixtures of OC-rich and siliciclastic sediment to be transported for distances of 1000 km. Preliminary experiments exploring both rock-derived and biospheric OC sources show minimal OC oxidation during active river transport, consistent with the idea that the majority of OC loss occurs during transient floodplain storage. These results are also consistent with new field data collected in the Rio Bermejo, Argentina, a lowland river traversing 800 km with no tributary inputs, where aged floodplain deposits have 3 to 10 times lower OC concentrations compared to modern river sediments. Together our field data and experiments support the hypothesis that oxidation of OC occurs primarily during

  11. Effects of Combined Hands-on Laboratory and Computer Modeling on Student Learning of Gas Laws: A Quasi-Experimental Study

    ERIC Educational Resources Information Center

    Liu, Xiufeng

    2006-01-01

    Based on current theories of chemistry learning, this study intends to test a hypothesis that computer modeling enhanced hands-on chemistry laboratories are more effective than hands-on laboratories or computer modeling laboratories alone in facilitating high school students' understanding of chemistry concepts. Thirty-three high school chemistry…

  12. Laboratory Studies of Sea-Ice-Wave Interactions

    NASA Astrophysics Data System (ADS)

    Monty, J.; Meylan, M. H.; Babanin, A. V.; Toffoli, A.; Bennetts, L.

    2016-12-01

    A world-first facility for studying the Marginal Ice Zone has been constructed in the Michell Hydrodynamics Laboratory at the University of Melbourne. A 14m long wave tank (0.75m wide, 0.6m deep) resides in a freezer, where air temperature can be controlled down to -15C. This permits the freezing of the water surface. Large stainless steel ice-making trays (up to 4 m long) are also available to create ice of desired thickness and microstructure, which can be lowered onto the water surface. A computer controlled wave generator is capable of creating waves of any desired form. The temperature of the water in the tank can also be controlled between 2 and 30C. The tank frame is constructed of marine-treated wood and the entire tank is glass and acrylic, permitting the use of corrosive fluids, such as salt water. Here we present the first laboratory experiments of break-up of a controlled thickness, fresh water ice sheet impacted by regular and JONSWAP spectrum surface waves. The geometry of the resultant ice-floes is measured with high-resolution, time-resolved imaging, providing the crucial data of floe size distribution. Initial observations show that, in the case of high steepness waves, the primary mechanisms of ice break-up at the ice edge are overwash and rafting, both of which put weight on the ice interior to the ice-water interface. This additional weight (and impact in the case of rafting) breaks more ice, which allows overwash and rafting deeper into the ice sheet, breaking more ice and so on. For lower steepness waves, overwash and rafting are still present but far less significant. Finally, results of vertical ice movement using laser height gauges will be presented showing the attenuation of waves into an ice sheet and through a pack of ice floes. These results are compared with field data and theory available (e.g. Squire & Moore, Nature, 1980 and Kohout et al., Nature, 2014).

  13. National survey on intra-laboratory turnaround time for some most common routine and stat laboratory analyses in 479 laboratories in China.

    PubMed

    Fei, Yang; Zeng, Rong; Wang, Wei; He, Falin; Zhong, Kun; Wang, Zhiguo

    2015-01-01

    To investigate the state of the art of intra-laboratory turnaround time (intra-TAT), provide suggestions and find out whether laboratories accredited by International Organization for Standardization (ISO) 15189 or College of American Pathologists (CAP) will show better performance on intra-TAT than non-accredited ones. 479 Chinese clinical laboratories participating in the external quality assessment programs of chemistry, blood gas, and haematology tests organized by the National Centre for Clinical Laboratories in China were included in our study. General information and the median of intra-TAT of routine and stat tests in last one week were asked in the questionnaires. The response rate of clinical biochemistry, blood gas, and haematology testing were 36% (479/1307), 38% (228/598), and 36% (449/1250), respectively. More than 50% of laboratories indicated that they had set up intra-TAT median goals and almost 60% of laboratories declared they had monitored intra-TAT generally for every analyte they performed. Among all analytes we investigated, the intra-TAT of haematology analytes was shorter than biochemistry while the intra-TAT of blood gas analytes was the shortest. There were significant differences between median intra-TAT on different days of the week for routine tests. However, there were no significant differences in median intra-TAT reported by accredited laboratories and non-accredited laboratories. Many laboratories in China are aware of intra-TAT control and are making effort to reach the target. There is still space for improvement. Accredited laboratories have better status on intra-TAT monitoring and target setting than the non-accredited, but there are no significant differences in median intra-TAT reported by them.

  14. National survey on intra-laboratory turnaround time for some most common routine and stat laboratory analyses in 479 laboratories in China

    PubMed Central

    Fei, Yang; Zeng, Rong; Wang, Wei; He, Falin; Zhong, Kun

    2015-01-01

    Introduction To investigate the state of the art of intra-laboratory turnaround time (intra-TAT), provide suggestions and find out whether laboratories accredited by International Organization for Standardization (ISO) 15189 or College of American Pathologists (CAP) will show better performance on intra-TAT than non-accredited ones. Materials and methods 479 Chinese clinical laboratories participating in the external quality assessment programs of chemistry, blood gas, and haematology tests organized by the National Centre for Clinical Laboratories in China were included in our study. General information and the median of intra-TAT of routine and stat tests in last one week were asked in the questionnaires. Results The response rate of clinical biochemistry, blood gas, and haematology testing were 36% (479 / 1307), 38% (228 / 598), and 36% (449 / 1250), respectively. More than 50% of laboratories indicated that they had set up intra-TAT median goals and almost 60% of laboratories declared they had monitored intra-TAT generally for every analyte they performed. Among all analytes we investigated, the intra-TAT of haematology analytes was shorter than biochemistry while the intra-TAT of blood gas analytes was the shortest. There were significant differences between median intra-TAT on different days of the week for routine tests. However, there were no significant differences in median intra-TAT reported by accredited laboratories and non-accredited laboratories. Conclusions Many laboratories in China are aware of intra-TAT control and are making effort to reach the target. There is still space for improvement. Accredited laboratories have better status on intra-TAT monitoring and target setting than the non-accredited, but there are no significant differences in median intra-TAT reported by them. PMID:26110033

  15. ASSESSMENT OF GENETIC DAMAGE INDICATORS IN FISH IN LABORATORY, MESOCOSM AND WATERSHED STUDIES

    EPA Science Inventory

    The micronucleus (MN) and single cell gel electrophoresis (SCG) ("Comet") techniques for measuring DNA damage are being evaluated for their potential use as indicators of exposure of fish populations. Laboratory studies employed acute exposures of bluegill sunfish to five model g...

  16. CUNNER(TAUTOGOLABRUS ADSPERSUS) AS A MODEL FISH FOR REPRODUCTIVE STUDIES IN THE LABORATORY

    EPA Science Inventory

    Cunner (Tautogolabrus adspersus) are being studied at our laboratory as a model species to determine the effects of endocrine disrupting chemicals (EDCs) on estuarine fish populations. Cunner was selected because this species is common in estuarine areas, is easily obtainable, an...

  17. Studying human disease genes in Caenorhabditis elegans: a molecular genetics laboratory project.

    PubMed

    Cox-Paulson, Elisabeth A; Grana, Theresa M; Harris, Michelle A; Batzli, Janet M

    2012-01-01

    Scientists routinely integrate information from various channels to explore topics under study. We designed a 4-wk undergraduate laboratory module that used a multifaceted approach to study a question in molecular genetics. Specifically, students investigated whether Caenorhabditis elegans can be a useful model system for studying genes associated with human disease. In a large-enrollment, sophomore-level laboratory course, groups of three to four students were assigned a gene associated with either breast cancer (brc-1), Wilson disease (cua-1), ovarian dysgenesis (fshr-1), or colon cancer (mlh-1). Students compared observable phenotypes of wild-type C. elegans and C. elegans with a homozygous deletion in the assigned gene. They confirmed the genetic deletion with nested polymerase chain reaction and performed a bioinformatics analysis to predict how the deletion would affect the encoded mRNA and protein. Students also performed RNA interference (RNAi) against their assigned gene and evaluated whether RNAi caused a phenotype similar to that of the genetic deletion. As a capstone activity, students prepared scientific posters in which they presented their data, evaluated whether C. elegans was a useful model system for studying their assigned genes, and proposed future directions. Assessment showed gains in understanding genotype versus phenotype, RNAi, common bioinformatics tools, and the utility of model organisms.

  18. Studying Human Disease Genes in Caenorhabditis elegans: A Molecular Genetics Laboratory Project

    PubMed Central

    Cox-Paulson, Elisabeth A.; Grana, Theresa M.; Harris, Michelle A.; Batzli, Janet M.

    2012-01-01

    Scientists routinely integrate information from various channels to explore topics under study. We designed a 4-wk undergraduate laboratory module that used a multifaceted approach to study a question in molecular genetics. Specifically, students investigated whether Caenorhabditis elegans can be a useful model system for studying genes associated with human disease. In a large-enrollment, sophomore-level laboratory course, groups of three to four students were assigned a gene associated with either breast cancer (brc-1), Wilson disease (cua-1), ovarian dysgenesis (fshr-1), or colon cancer (mlh-1). Students compared observable phenotypes of wild-type C. elegans and C. elegans with a homozygous deletion in the assigned gene. They confirmed the genetic deletion with nested polymerase chain reaction and performed a bioinformatics analysis to predict how the deletion would affect the encoded mRNA and protein. Students also performed RNA interference (RNAi) against their assigned gene and evaluated whether RNAi caused a phenotype similar to that of the genetic deletion. As a capstone activity, students prepared scientific posters in which they presented their data, evaluated whether C. elegans was a useful model system for studying their assigned genes, and proposed future directions. Assessment showed gains in understanding genotype versus phenotype, RNAi, common bioinformatics tools, and the utility of model organisms. PMID:22665589

  19. The Uranium from Seawater Program at the Pacific Northwest National Laboratory: Overview of Marine Testing, Adsorbent Characterization, Adsorbent Durability, Adsorbent Toxicity, and Deployment Studies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gill, Gary A.; Kuo, Li-Jung; Janke, Chris J.

    The Pacific Northwest National Laboratory’s (PNNL) Marine Science Laboratory (MSL) located along the coast of Washington State is evaluating the performance of uranium adsorption materials being developed for seawater extraction under realistic marine conditions with natural seawater. Two types of exposure systems were employed in this program: flow-through columns for testing of fixed beds of individual fibers and pellets and a recirculating water flume for testing of braided adsorbent material. Testing consists of measurements of the adsorption of uranium and other elements from seawater as a function of time, typically 42 to 56 day exposures, to determine the adsorbent capacitymore » and adsorption rate (kinetics). Analysis of uranium and other trace elements collected by the adsorbents was conducted following strong acid digestion of the adsorbent with 50% aqua regia using either Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) or Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The ORNL 38H adsorbent had a 56 day adsorption capacity of 3.30 ± 0.68 g U/ kg adsorbent (normalized to a salinity of 35 psu), a saturation adsorption capacity of 4.89 ± 0.83 g U/kg of adsorbent material (normalized to a salinity of 35 psu) and a half-saturation time of 28 ± 10 days. The AF1 adsorbent material had a 56 day adsorption capacity of 3.9 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu), a saturation capacity of 5.4 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu) and a half saturation time of 23 ± 2 days. The ORNL amidoxime-based adsorbent materials are not specific for uranium, but also adsorb other elements from seawater. The major doubly charged cations in seawater (Ca and Mg) account for a majority of the cations adsorbed (61% by mass and 74% by molar percent). For the ORNL AF1 adsorbent material, U is the 4th most abundant element adsorbed by mass and 7th most abundant by molar percentage« less

  20. Wiki Laboratory Notebooks: Supporting Student Learning in Collaborative Inquiry-Based Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Lawrie, Gwendolyn Angela; Grøndahl, Lisbeth; Boman, Simon; Andrews, Trish

    2016-06-01

    Recent examples of high-impact teaching practices in the undergraduate chemistry laboratory that include course-based undergraduate research experiences and inquiry-based experiments require new approaches to assessing individual student learning outcomes. Instructors require tools and strategies that can provide them with insight into individual student contributions to collaborative group/teamwork throughout the processes of experimental design, data analysis, display and communication of their outcomes in relation to their research question(s). Traditional assessments in the form of laboratory notebooks or experimental reports provide limited insight into the processes of collaborative inquiry-based activities. A wiki environment offers a collaborative domain that can potentially support collaborative laboratory processes and scientific record keeping. In this study, the effectiveness of the wiki in supporting laboratory learning and assessment has been evaluated through analysis of the content and histories for three consenting, participating groups of students. The conversational framework has been applied to map the relationships between the instructor, tutor, students and laboratory activities. Analytics that have been applied to the wiki platform include: character counts, page views, edits, timelines and the extent and nature of the contribution by each student to the wiki. Student perceptions of both the role and the impact of the wiki on their experiences and processes have also been collected. Evidence has emerged from this study that the wiki environment has enhanced co-construction of understanding of both the experimental process and subsequent communication of outcomes and data. A number of features are identified to support success in the use of the wiki platform for laboratory notebooks.

  1. Plasma creatinine in dogs: intra- and inter-laboratory variation in 10 European veterinary laboratories

    PubMed Central

    2011-01-01

    Background There is substantial variation in reported reference intervals for canine plasma creatinine among veterinary laboratories, thereby influencing the clinical assessment of analytical results. The aims of the study was to determine the inter- and intra-laboratory variation in plasma creatinine among 10 veterinary laboratories, and to compare results from each laboratory with the upper limit of its reference interval. Methods Samples were collected from 10 healthy dogs, 10 dogs with expected intermediate plasma creatinine concentrations, and 10 dogs with azotemia. Overlap was observed for the first two groups. The 30 samples were divided into 3 batches and shipped in random order by postal delivery for plasma creatinine determination. Statistical testing was performed in accordance with ISO standard methodology. Results Inter- and intra-laboratory variation was clinically acceptable as plasma creatinine values for most samples were usually of the same magnitude. A few extreme outliers caused three laboratories to fail statistical testing for consistency. Laboratory sample means above or below the overall sample mean, did not unequivocally reflect high or low reference intervals in that laboratory. Conclusions In spite of close analytical results, further standardization among laboratories is warranted. The discrepant reference intervals seem to largely reflect different populations used in establishing the reference intervals, rather than analytical variation due to different laboratory methods. PMID:21477356

  2. Rocket and laboratory studies in astronomy

    NASA Technical Reports Server (NTRS)

    Feldman, Paul D.

    1994-01-01

    This report covers the period from September 1, 1993 to August 31, 1994. During the reporting period we launched the Faint Object Telescope to measure the absolute flux of a hot white dwarf star in the spectral range below 1200 A. This experiment was not successful due to a failure of an electronics unit in the onboard TV acquisition system. The source of the failure has been identified and corrected and is described in detail below. The payload was recovered in excellent condition and we are planning to refurbish it for flight during the November 1995 Australia campaign. We have continued our laboratory studies of the ultraviolet performance of charge-coupled-detector (CCD) arrays and plan to include a UV-sensitive CCD in a new payload that was assembled during the current period. The objective of the experiment is the ultraviolet imaging of Jupiter and we are scheduled to launch the payload, 36.115UG, in May-June 1995. We have also begun the design of a high-resolution FUV spectrograph for a future flight of the FOT and have just recently received a high line density grating fabricated by Jobin-Yvon, S.A. (France) for evaluation. Work has continued on the analysis of data from previous rocket experiments.

  3. EFFECTS OF FOOD AVAILABILITY ON SURVIVAL, GROWTH, AND REPRODUCTION OF THE GRASS SHRIMP PALAEMONETES PUGIO: A LABORATORY STUDY

    EPA Science Inventory

    Grass shrimp are abundant, ecologically important inhabitants of estuarine ecosystems; adults and embryos have been used extensively in laboratory experiments, including studies of the impacts of environmental toxicants. However, optimal laboratory feeding conditions for grass sh...

  4. Fred Hutchinson Cancer Research Center, Seattle, Washington: Laboratories for the 21st Century Case Studies (Revision)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    2002-03-01

    This case study was prepared by participants in the Laboratories for the 21st Century program, a joint endeavor of the U.S. Environmental Protection Agency and the U.S. Department of Energy's Federal Energy Management Program. The goal of this program is to foster greater energy efficiency in new laboratory buildings for both the public and the private sectors. Retrofits of existing laboratories are also encouraged. The energy-efficient features of the laboratories in the Fred Hutchinson Cancer Research Center complex in Seattle, Washington, include extensive use of efficient lighting, variable-air-volume controls, variable-speed drives, motion sensors, and high-efficiency chillers and motors. With aboutmore » 532,000 gross square feet, the complex is estimated to use 33% less electrical energy than most traditional research facilities consume because of its energy-efficient design and features.« less

  5. Laboratory Modelling of the Effect of Bend Orientation on the Morphological Development of Alluvial Channels

    NASA Astrophysics Data System (ADS)

    Good, R. G. R.; Sullivan, C.; Binns, A. D.

    2017-12-01

    Bend orientation, or skewness, in natural streams is often caused by riparian vegetation or underlying geology that lead to a meandering stream following a non-sinuous path. The bend orientation affects how the fluid momentum interacts with the bed and banks, which can alter the location and shape of bedforms as well as the channel planform geometry. An experimental study in a laboratory sand flume with movable bed and banks (5.6 m long, 1.9 m wide; D50 = 0.7 mm; B = 0.2m; 3 wavelengths) was carried out to quantify the effect of bend orientation on bedform development and planform changes. While previous research in the literature has found that channels with an upstream bend orientation had a less developed secondary flow than a downstream orientation, few studies on the morphological development of streams having varying bend orientation have been conducted. In total, three runs were carried out using channels with upstream, downstream, and no skewness. The runs progressed in a series of time-steps to monitor the morphological evolution of the streams with time. Sediment transport rates were quantified at the outlet, flow was measured using an ultrasonic flow meter at the inlet, flow depths were measured at the apex of the bends, and channel morphology was measured at each time step using Structure-from-Motion photogrammetry with Agisoft Photoscan. Bend orientation was found to influence the position of the point bar development as well as the locations of maximum and minimum channel migration. Relative to the bend apex, point bars tended to be positioned in the same direction as the channel skewness. Channel width showed the greatest variation with the upstream orientation, with the channel narrowing before the apex where the channel flows in the up-valley direction, and widening downstream of the apex. These results show that the channel orientation influences the morphological development of the channel bed and banks. The effect of velocity structure and

  6. ATTENUATION/STABILIZATION OF ARSENIC BY IRON (HYDR)OXIDES IN SOILS/SEDIMENTS: LABORATORY STUDY.

    EPA Science Inventory

    Laboratory studies will be performed to assess the role of naturally occurring soil/sediment iron (hydr)oxides on the attenuation/stabilization of arsenic. Changes in the reversibility of arsenic partitioning will be assessed as a function of aging time using model experimental ...

  7. Pre-Analytical Components of Risk in Four Branches of Clinical Laboratory in Romania--Prospective Study.

    PubMed

    David, Remona E; Dobreanu, Minodora

    2016-01-01

    Development of quality measurement principles is a strategic point for each clinical laboratory. Preexamination process is the most critical and the most difficult to be managed. The aim of this study is to identify, quantify, and monitor the nonconformities of the pre-analytical process using quality indicators that can affect the patient's health safety in four different locations of a Romanian private clinical laboratory. The study group consisted of all the analysis requests received by the departments of biochemistry, hematology, and coagulation from January through March 2015. In order to collect the pre-analytical nonconformities, we created a "Risk Budget", using the entries from the "Evidence notebook--non-conform samples" from the above mentioned departments. The laboratory established the quality indicators by means of the risk management technique in order to identify and control the sources of errors, FMEA (Failure Modes and Effects Analyses), which had been implemented and monitored for its purposes and special needs. For the assessment of the control level over the processes, the results were transformed on the Six Sigma scale, using the Westgard calculation method and being obtained in this way the frequency with which an error may occur. (https://www.westgard. com/six-sigma-calculators.htm). The obtained results prove that the quantification and monitoring of the indicators can be a control instrument for the pre-analytic activities. The calculation of the Six Sigma value adds extra information to the study because it allows the detection of the processes which need improvement (Sigma value higher than 4 represents a well controlled process). The highest rates were observed for the hemolyzed and the lipemic samples, in the department of biochemistry and hemolyzed, insufficient sample volume, or clotted samples for the department of hematology and coagulation. Significant statistical differences between laboratories participating in the study have

  8. An inter-laboratory comparison study on transfer, persistence and recovery of DNA from cable ties.

    PubMed

    Steensma, Kristy; Ansell, Ricky; Clarisse, Lindy; Connolly, Edward; Kloosterman, Ate D; McKenna, Louise G; van Oorschot, Roland A H; Szkuta, Bianca; Kokshoorn, Bas

    2017-11-01

    To address questions on the activity that led to the deposition of biological traces in a particular case, general information on the probabilities of transfer, persistence and recovery of cellular material in relevant scenarios is necessary. These figures may be derived from experimental data described in forensic literature when conditions relevant to the case were included. The experimental methodology regarding sampling, DNA extraction, DNA typing and profile interpretation that were used to generate these published data may differ from those applied in the case and thus the applicability of the literature data may be questioned. To assess the level of variability that different laboratories obtain when similar exhibits are analysed, we performed an inter-laboratory study between four partner laboratories. Five sets of 20 cable ties bound by different volunteers were distributed to the participating laboratories and sampled and processed according to the in-house protocols. Differences were found for the amount of retrieved DNA, as well as for the reportability and composition of the DNA profiles. These differences also resulted in different probabilities of transfer, persistence and recovery for each laboratory. Nevertheless, when applied to a case example, these differences resulted in similar assignments of weight of evidence given activity-level propositions. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. REMOVAL OF TANK AND SEWER SEDIMENT BY GATE FLUSHING: COMPUTATIONAL FLUID DYNAMICS MODEL STUDIES

    EPA Science Inventory

    This presentation will discuss the application of a computational fluid dynamics 3D flow model to simulate gate flushing for removing tank/sewer sediments. The physical model of the flushing device was a tank fabricated and installed at the head-end of a hydraulic flume. The fl...

  10. Interactions between sediment storage and bed material transport: A field and flume study

    Treesearch

    Bonnie J. Smith; Thomas E. Lisle; Diane G. Sutherland; Sue Hilton; Harvey M. Kelsey; Eileen M. Cashman

    2002-01-01

    Significant channel aggradation events have occurred in numerous coastal northern California watersheds over the past 50 years, leaving lasting impacts on stream channel morphology and habitats. Our study focuses on sediment movement and channel morphology following large aggradation events and specifically focuses on the relationship between volume of stored sediment...

  11. Morpho-dynamics of mountain streams: from laboratory experiments to field observations

    NASA Astrophysics Data System (ADS)

    Mettra, François; Lane, Stuart Nicholas; Heyman, Joris; Ancey, Christophe

    2017-04-01

    Due to the complexity of mountain stream evolution and its causes, it is judicious to conduct flume experiments to better understand the morpho-dynamics of steep river channels. A series of long-term experiments under steady conditions revealed the high internal variability of transport processes (including erosion and deposition events). In particular, high fluctuations over time of the sediment volume stored in the channel (or released from the channel) were observed for the steepest channel experiments at intermittent transport conditions. These conditions imply an autogenic regulation of the sediment transport process. When these were extended to non-steady conditions, repeated flood events suggested a hysteresis effect on sediment transport but where the forcing frequency (of the repeated floods) plays an important role in the response of the channel system. The results are compared with preliminary field observations from continuous measurements in Swiss Alpine rivers. Simple mechanisms of steep river channel behavior are proposed.

  12. Laboratory Identity: A Linguistic Landscape Analysis of Personalized Space within a Microbiology Laboratory

    ERIC Educational Resources Information Center

    Hanauer, David I.

    2010-01-01

    This study provides insights into what constitutes a laboratory identity and the ways in which it is spatially constructed. This article explores students' professional identities as microbiologists as manifest in their usage of representational space in a laboratory and as such extends understandings of science identity and spatial identity. The…

  13. LABORATORY STUDIES ON THE STABILITY AND TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL

    EPA Science Inventory

    The stability and transport of radio-labeled Fe2O3 particles were studied using laboratory batch and column techniques. Core material collected from shallow sand and gravel aquifer was used as the immobile column matrix material. Variables in the study included flow rate, pH, i...

  14. Sediment erosion and transport at the Rio Grande mouth : report for the National Border Technology Program and International Boundary and Water Commission.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chapin, D. Michael, Jr.; Langford, Richard; Neu, Roene

    2003-11-01

    The mouth of the Rio Grande has become silted up, obstructing its flow into the Gulf of Mexico. This is problematic in that it has created extensive flooding. The purpose of this study was to determine the erosion and transport potential of the sediments obstructing the flow of the Rio Grande by employing a unique Mobile High Shear Stress flume developed by Sandia's Carlsbad Programs Group for the US Army Corps of Engineers. The flume measures in-situ sediment erosion properties at shear stresses ranging from normal flow to flood conditions for a variable depth sediment core. The flume is inmore » a self-contained trailer that can be placed on site in the field. Erosion rates and sediment grain size distributions were determined from sediment samples collected in and around the obstruction and were subsequently used to characterize the erosion potential of the sediments under investigation.« less

  15. Laboratory Studies of FeO and NiO Chemiluminescence

    NASA Astrophysics Data System (ADS)

    Kalogerakis, K. S.; Bartlett, N. C.; Copeland, R. A.; Slanger, T. G.

    2013-12-01

    Although the terrestrial nightglow spectrum has been studied for over a century, new identifications of spectral features continue to be made. Recently, FeO* continuum emissions in the mesosphere were identified by comparison of results from the OSIRIS spectrometer to existing laboratory spectra [1]. This discovery has sparked a renewal of interest in the reactions of meteoric metals with mesospheric gases [2,3], and has motivated the current study. We report laboratory-based chemiluminescence spectra from the reactions Fe + O3 and Ni + O3 produced under various conditions. Iron and nickel vapor was prepared in a vacuum cell using laser ablation at 248 and 800 nm in the presence of ozone. Emission spectra from FeO* and NiO* were recorded in the region of 450-700 nm using a commercial fiber-coupled spectrometer and compared to previous results using different methods. Knowledge of the excited-state production efficiency of Fe + O3 → FeO* + O2 and the analogous reaction with Ni is critical in modeling upper atmospheric dynamics of meteoric metal layers. The only relevant experimental study in the literature for iron oxide is from West and Broida [4], who reported a yield of approximately 2% at around 1 Torr, in stark contrast with the 100% efficiency used in relevant model calculations [5]. This work was supported by the National Science Foundation's Aeronomy Program under grant AGS-0637433. References 1. W.F.J. Evans, R.L. Gattinger, T.G. Slanger, D.V. Saran, D.A. Degenstein, and E.J. Llewellyn, Geophys. Res. Lett., 37, L22105 (2010). 2. D.V. Saran, T.G. Slanger, W. Feng, and J.M.C. Plane, J. Geophys. Res. 116, D12303 (2011). 3. R.L. Gattinger, W.F.J. Evans, and E.J. Llewellyn, Canadian Journal of Physics 89, 869 (2011). 4. J.B. West and H.P. Broida, J. Chem. Phys. 62, 2566 (1975 ). 5. C.S. Gardner, J.M.C. Plane, W.L. Pan, T. Vondrak, B.J. Murray, and X.Z. Chu, J. Geophys. Res. 110, D10302 (2005).

  16. The Characteristics of Turbulent Flows on Forested Floodplains

    NASA Astrophysics Data System (ADS)

    Darby, S. E.; Richardson, K.; Sear, D. A.

    2008-12-01

    Forested floodplain environments represent the undisturbed land cover of most river systems, but they are under threat from human activities. An understanding of forest floodplain processes therefore has relevance to ecosystem conservation and restoration, and the interpretation of pre-historic river and floodplain evolution. However, relatively little research has been undertaken within forested floodplain environments, a particular limitation being an absence of empirical data regarding the hydraulic characteristics of over bank flows, which inhibits the development of flow, sediment and solute transport models. Forest floodplain flows are strongly modified by floodplain topography and the presence of vegetation and organic debris on the woodland floor. In such instances flow blockage and diversions are common, and there is the possibility of intense turbulence generation, both by wakes and by shear. To address this gap we have undertaken a study based on a floodplain reach located in the Highland Water Research Catchment (southern England), a UK national reference site for lowland floodplain forest streams. Given the difficulties of acquiring spatially-distributed hydraulic data sets during floods, our methodological approach has been to attempt to replicate over bank flow observed at the study site within a laboratory flume. This is necessary to acquire flow velocity data at sufficiently high spatial resolution to evaluate the underlying flow mechanics and has been achieved using (i) a large (21m) flume to achieve 1:1 hydraulic scaling and (ii) a novel method of precisely replicating the floodplain topography within the flume. Specifically, accurate replication of a representative floodplain patch was achieved by creating a 1:1 scale Physical Terrain Model (PTM) from high-density polyurethane using a computer-controlled milling process based on Digital Terrain Model (DTM) data, the latter acquired via terrestrial laser scanning (TLS) survey. The PTM was

  17. How compliant are technicians with universal safety measures in medical laboratories in Croatia? – A pilot study

    PubMed Central

    Dukic, Kristina; Zoric, Matea; Pozaic, Petra; Starcic, Jelena; Culjak, Marija; Saracevic, Andrea; Miler, Marijana

    2015-01-01

    Introduction This pilot study aimed to investigate the use of personal protective equipment (PPE) and compliance to the code of conduct (rules defined in institutional, governmental and professional guidelines) among laboratory technicians in Croatian medical laboratories. In addition, we explored the differences in compliance between participants of different age groups, laboratory ownership and accreditation status. Materials and methods An anonymous and voluntary survey with 15 questions was conducted among Croatian medical laboratory technicians (N = 217). The questions were divided into two groups: demographic characteristics and the use of PPE. The questions of the second part were graded according to the Likert scale (1-4) and an overall score, shown as median and range (min-max), was calculated for each participant. Differences between the overall scores were tested for each group of participants. Results The majority of participants always wear protective clothes at work, 38.7% of them always wear gloves in daily routine, more than 30.0% consume food and almost half of them drink beverages at workplace. A significantly lower overall score was found for participants working in public compared to private laboratories (36 (16-40) vs. 40 (31-40), P < 0.001). There were no statistically significant differences in overall scores for participants of different age groups (P = 0.456) and laboratory accreditation status (P = 0.081). Conclusion A considerable percentage of laboratory technicians in Croatian medical laboratories do not comply with safety measures. Lack of compliance is observed in all personnel regardless laboratory accreditation and participants’ age. However, those working in private laboratories adhere more to the code of conduct. PMID:26526817

  18. Postharvest Reduction of Coliphage MS2 from Romaine Lettuce during Simulated Commercial Processing with and without a Chlorine-Based Sanitizer.

    PubMed

    Wengert, Samantha L; Aw, Tiong Gim; Ryser, Elliot T; Rose, Joan B

    2017-02-01

    Viral foodborne outbreaks are a serious threat to public health, and fresh produce is becoming increasingly recognized as a transmission vehicle. To limit foodborne disease, ready-to-eat leafy greens are typically washed with a chlorine-based sanitizer during commercial production. This study assessed the efficacy of a chlorine-based sanitizer against coliphage MS2, as a potential surrogate for foodborne viruses, on fresh-cut romaine lettuce during simulated commercial production using a small-scale processing line. Before processing, romaine lettuce was inoculated to contain approximately 10 5 and 10 6 PFU/g of MS2 for experiments with and without sanitizer, respectively. Lettuce samples were collected following each stage of processing, which included mechanical shredding, 2 min of flume washing (with or without 25 ppm of free chlorine), shaker table dewatering, and centrifugal drying. In addition, the spent centrifuge water and flume wash water were collected, with the flume water concentrated using hollow-fiber ultrafiltration. MS2 was recovered from lettuce in Tris-glycine buffer and quantified as PFUs in a double-agar overlay assay. The greatest reduction in MS2 occurred between shredding and flume washing, with levels remaining relatively stable following flume washing with or without 25 ppm of free chlorine. Average total reductions of 0.8 and 1.0 log PFU/g were seen after processing with and without the sanitizer, respectively, with no statistical difference observed between the two treatments (P > 0.05). The average MS2 level in the spent centrifugation water started at 4.0 log PFU/ml for experiments with sanitizer and the average MS2 reduction in the flume wash water was 4 log (PFU) for experiments with sanitizer, demonstrating that removals could be achieved in the water itself. These findings suggest that the currently recommended commercial production practices are unable to effectively decrease viruses once they have attached to leafy greens during

  19. Emotional intelligence in medical laboratory science

    NASA Astrophysics Data System (ADS)

    Price, Travis

    The purpose of this study was to explore the role of emotional intelligence (EI) in medical laboratory science, as perceived by laboratory administrators. To collect and evaluate these perceptions, a survey was developed and distributed to over 1,400 medical laboratory administrators throughout the U.S. during January and February of 2013. In addition to demographic-based questions, the survey contained a list of 16 items, three skills traditionally considered important for successful work in the medical laboratory as well as 13 EI-related items. Laboratory administrators were asked to rate each item for its importance for job performance, their satisfaction with the item's demonstration among currently working medical laboratory scientists (MLS) and the amount of responsibility college-based medical laboratory science programs should assume for the development of each skill or attribute. Participants were also asked about EI training in their laboratories and were given the opportunity to express any thoughts or opinions about EI as it related to medical laboratory science. This study revealed that each EI item, as well as each of the three other items, was considered to be very or extremely important for successful job performance. Administrators conveyed that they were satisfied overall, but indicated room for improvement in all areas, especially those related to EI. Those surveyed emphasized that medical laboratory science programs should continue to carry the bulk of the responsibility for the development of technical skills and theoretical knowledge and expressed support for increased attention to EI concepts at the individual, laboratory, and program levels.

  20. Multi-Laboratory Study of Five Methods for the Determination of Brevetoxins in Shellfish Tissue Extracts.

    PubMed

    Dickey, Robert W; Plakas, Steven M; Jester, Edward L E; El Said, Kathleen R; Johannessen, Jan N; Flewelling, Leanne J; Scott, Paula; Hammond, Dan G; Van Dolah, Frances M; Leighfield, Tod A; Bottein Dachraoui, Marie-Yasmine; Ramsdell, John S; Pierce, Richard H; Henry, Mike S; Poli, Mark A; Walker, Calvin; Kurtz, Jan; Naar, Jerome; Baden, Daniel G; Musser, Steve M; White, Kevin D; Truman, Penelope; Miller, Aaron; Hawryluk, Timothy P; Wekell, Marleen M; Stirling, David; Quilliam, Michael A; Lee, Jung K

    A thirteen-laboratory comparative study tested the performance of four methods as alternatives to mouse bioassay for the determination of brevetoxins in shellfish. The methods were N2a neuroblastoma cell assay, two variations of the sodium channel receptor binding assay, competitive ELISA, and LC/MS. Three to five laboratories independently performed each method using centrally prepared spiked and naturally incurred test samples. Competitive ELISA and receptor binding (96-well format) compared most favorably with mouse bioassay. Between-laboratory relative standard deviations (RSDR) ranged from 10 to 20% for ELISA and 14 to 31% for receptor binding. Within-laboratory (RSDr) ranged from 6 to 15% for ELISA, and 5 to 31% for receptor binding. Cell assay was extremely sensitive but data variation rendered it unsuitable for statistical treatment. LC/MS performed as well as ELISA on spiked test samples but was inordinately affected by lack of toxin-metabolite standards, uniform instrumental parameters, or both, on incurred test samples. The ELISA and receptor binding assay are good alternatives to mouse bioassay for the determination of brevetoxins in shellfish.

  1. Studying epigenetic DNA modifications in undergraduate laboratories using complementary bioinformatic and molecular approaches.

    PubMed

    Militello, Kevin T

    2013-01-01

    Epigenetic inheritance is the inheritance of genetic information that is not based on DNA sequence alone. One type of epigenetic information that has come to the forefront in the last few years is modified DNA bases. The most common modified DNA base in nature is 5-methylcytosine. Herein, we describe a laboratory experiment that combines bioinformatic and molecular approaches to study the presence and abundance of 5-methylcytosine in different organisms. Students were originally provided with the protein sequence of the Xenopus laevis DNMT1 cytosine-5 DNA methyltransferase and used BLASTP searches to detect the presence of protein orthologs in the genomes of several organisms including Homo sapiens, Mus musculus, Plasmodium falciparum, Drosophila melanogaster, Saccharomyces cerevisiae, Arabidopsis thaliana, and Caenorhabditis elegans. Students generated hypotheses regarding the presence and abundance of 5-methylcytosine in these organisms based on their bioinformatics data, and directly tested their predictions on a subset of DNAs using restriction enzyme isoschizomer assays. A southern blotting assay to answer the same question is also presented. In addition to exposure to the field of epigenetics, the strengths of the laboratory are students are able to make predictions using bioinformatic tools and quickly test them in the laboratory. In addition, students are exposed to two potential misinterpretations of bioinformatic search data. The laboratory is easily modified to incorporate outside research interests in epigenetics. © 2013 by The International Union of Biochemistry and Molecular Biology.

  2. Non-physics peer demonstrators in undergraduate laboratories: a study of students’ perceptions

    NASA Astrophysics Data System (ADS)

    Braun, Michael; Kirkup, Les

    2016-01-01

    Laboratory demonstrators play a crucial role in facilitating students’ learning in physics subjects. Inspired by the success of peer-led activities, we introduced peer demonstrators to support student learning in first-year physics subjects that enrol students not intending to major in physics. Surveys were administered to 1700 students over 4 years in four subjects to examine student perceptions of how demonstrators assisted them in the laboratory. Scores awarded to peer demonstrators by students were no lower than those awarded to demonstrators traditionally employed in the first year physics laboratory. These latter demonstrators were drawn mainly from the ranks of physics research students. The findings validate the recruitment of peer demonstrators and will be used to inform the recruitment and support programmes for laboratory demonstrators.

  3. Microwave remote sensing laboratory design

    NASA Technical Reports Server (NTRS)

    Friedman, E.

    1979-01-01

    Application of active and passive microwave remote sensing to the study of ocean pollution is discussed. Previous research efforts, both in the field and in the laboratory were surveyed to derive guidance for the design of a laboratory program of research. The essential issues include: choice of radar or radiometry as the observational technique; choice of laboratory or field as the research site; choice of operating frequency; tank sizes and material; techniques for wave generation and appropriate wavelength spectrum; methods for controlling and disposing of pollutants used in the research; and pollutants other than oil which could or should be studied.

  4. 1. View of Lake Hodges Dam showing the origin of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View of Lake Hodges Dam showing the origin of the flume at left. View is looking east. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA

  5. 20. Detail, looking west, beneath Trestle 4, showing the metal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. Detail, looking west, beneath Trestle 4, showing the metal flume channel, and the sediment clean-out valve. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA

  6. Inquiring Scaffolds in Laboratory Tasks: An Instance of a "Worked Laboratory Guide Effect"?

    ERIC Educational Resources Information Center

    Schmidt-Borcherding, Florian; Hänze, Martin; Wodzinski, Rita; Rincke, Karsten

    2013-01-01

    The study explores if established support devices for paper-pencil problem solving, namely worked examples and incremental scaffolds, are applicable to laboratory tasks. N?=?173 grade eight students solved in dyads a physics laboratory task in one of three conditions. In condition A (unguided problem solving), students were asked to determine the…

  7. A 2-year study of patient safety competency assessment in 29 clinical laboratories.

    PubMed

    Reed, Robyn C; Kim, Sara; Farquharson, Kara; Astion, Michael L

    2008-06-01

    Competency assessment is critical for laboratory operations and is mandated by the Clinical Laboratory Improvement Amendments of 1988. However, no previous reports describe methods for assessing competency in patient safety. We developed and implemented a Web-based tool to assess performance of 875 laboratory staff from 29 laboratories in patient safety. Question categories included workplace culture, categorizing error, prioritization of patient safety interventions, strength of specific interventions, and general patient safety concepts. The mean score was 85.0%, with individual scores ranging from 56% to 100% and scores by category from 81.3% to 88.6%. Of the most difficult questions (<72% correct), 6 were about intervention strength, 3 about categorizing error, 1 about workplace culture, and 1 about prioritization of interventions. Of the 13 questions about intervention strength, 6 (46%) were in the lowest quartile, suggesting that this may be a difficult topic for laboratory technologists. Computer-based competency assessments help laboratories identify topics for continuing education in patient safety.

  8. Extraneous tissue in surgical pathology: a College of American Pathologists Q-Probes study of 275 laboratories.

    PubMed

    Gephardt, G N; Zarbo, R J

    1996-11-01

    To develop a multi-institutional reference database of extraneous tissue (contaminants) in surgical pathology. In 1994, participants in the College of American Pathologists Q-Probes quality improvement program performed prospective and retrospective evaluations of extraneous tissue found in surgical pathology microscopic sections for a period of 4 weeks or until 1000 slides were reviewed in each participating laboratory. Two hundred seventy-five surgical pathology laboratories institutions, predominantly from North America. Extraneous tissue contamination rate for slides in prospective and retrospective reviews; staffing and practice procedures; location of extraneous tissue on slides; type of extraneous tissue (normal, abnormal, nonneoplastic, neoplasm, microorganisms, etc); class of extraneous tissue (slide or block contaminants); source of extraneous tissue (different or same case); origin of extraneous tissue (pathology laboratory, physician's office or operating room); and degree of diagnostic difficulty caused by extraneous tissue. Three hundred twenty-one thousand seven hundred fifty-seven slides were reviewed in the prospective study and 57083 slides in the retrospective study. There was an overall extraneous tissue rate of 0.6% of slides (2074/321757) in the prospective study and 2.9% of slides (1653/57083) in the retrospective study. Of those slides with extraneous tissue, the extraneous tissue was located near diagnostic tissue sections in 59.5% of the slides reviewed prospectively and in 25.3% of slides reviewed retrospectively; deeper sections were performed to evaluate extraneous tissue in 12.2% of prospective cases and in 3.1% of retrospective cases. Of the laboratories, 98% had written guidelines for changing solution in tissue processors, and 64.9% had guidelines for maintaining water baths free of extraneous tissue. A total of 98.9% used lens paper, filter bags, or sponges for processing fragmented and small specimens. Written protocols for

  9. Measuring meaningful learning in the undergraduate chemistry laboratory

    NASA Astrophysics Data System (ADS)

    Galloway, Kelli R.

    The undergraduate chemistry laboratory has been an essential component in chemistry education for over a century. The literature includes reports on investigations of singular aspects laboratory learning and attempts to measure the efficacy of reformed laboratory curriculum as well as faculty goals for laboratory learning which found common goals among instructors for students to learn laboratory skills, techniques, experimental design, and to develop critical thinking skills. These findings are important for improving teaching and learning in the undergraduate chemistry laboratory, but research is needed to connect the faculty goals to student perceptions. This study was designed to explore students' ideas about learning in the undergraduate chemistry laboratory. Novak's Theory of Meaningful Learning was used as a guide for the data collection and analysis choices for this research. Novak's theory states that in order for meaningful learning to occur the cognitive, affective, and psychomotor domains must be integrated. The psychomotor domain is inherent in the chemistry laboratory, but the extent to which the cognitive and affective domains are integrated is unknown. For meaningful learning to occur in the laboratory, students must actively integrate both the cognitive domain and the affective domains into the "doing" of their laboratory work. The Meaningful Learning in the Laboratory Instrument (MLLI) was designed to measure students' cognitive and affective expectations and experiences within the context of conducting experiments in the undergraduate chemistry laboratory. Evidence for the validity and reliability of the data generated by the MLLI were collected from multiple quantitative studies: a one semester study at one university, a one semester study at 15 colleges and universities across the United States, and a longitudinal study where the MLLI was administered 6 times during two years of general and organic chemistry laboratory courses. Results from

  10. Biosafety and biosecurity in veterinary laboratories

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Finley, Melissa R.; Astuto-Gribble, Lisa M.; Brass, Van Hildren

    Here, with recent outbreaks of MERS-Cov, Anthrax, Nipah, and Highly Pathogenic Avian Influenza, much emphasis has been placed on rapid identification of infectious agents globally. As a result, laboratories are building capacity, conducting more advanced and sophisticated research, increasing laboratory staff, and establishing collections of dangerous pathogens in an attempt to reduce the impact of infectious disease outbreaks and characterize disease causing agents. With this expansion, the global laboratory community has started to focus on laboratory biosafety and biosecurity to prevent the accidental and/or intent ional release o f these agents. Laboratory biosafety and biosecurity systems are used around themore » world to help mit igate the risks posed by dangerous pathogens in the laboratory. Veterinary laboratories carry unique responsibilities to workers and communities to safely and securely handle disease causing microorganisms. Many microorganisms studied in veterinary laboratories not only infect animals, but also have the potential to infect humans. This paper will discuss the fundamentals of laboratory biosafety and biosecurity.« less

  11. Iterative outlier removal: A method for identifying outliers in laboratory recalibration studies

    PubMed Central

    Parrinello, Christina M.; Grams, Morgan E.; Sang, Yingying; Couper, David; Wruck, Lisa M.; Li, Danni; Eckfeldt, John H.; Selvin, Elizabeth; Coresh, Josef

    2016-01-01

    Background Extreme values that arise for any reason, including through non-laboratory measurement procedure-related processes (inadequate mixing, evaporation, mislabeling), lead to outliers and inflate errors in recalibration studies. We present an approach termed iterative outlier removal (IOR) for identifying such outliers. Methods We previously identified substantial laboratory drift in uric acid measurements in the Atherosclerosis Risk in Communities (ARIC) Study over time. Serum uric acid was originally measured in 1990–92 on a Coulter DACOS instrument using an uricase-based measurement procedure. To recalibrate previous measured concentrations to a newer enzymatic colorimetric measurement procedure, uric acid was re-measured in 200 participants from stored plasma in 2011–13 on a Beckman Olympus 480 autoanalyzer. To conduct IOR, we excluded data points >3 standard deviations (SDs) from the mean difference. We continued this process using the resulting data until no outliers remained. Results IOR detected more outliers and yielded greater precision in simulation. The original mean difference (SD) in uric acid was 1.25 (0.62) mg/dL. After four iterations, 9 outliers were excluded, and the mean difference (SD) was 1.23 (0.45) mg/dL. Conducting only one round of outlier removal (standard approach) would have excluded 4 outliers (mean difference [SD] = 1.22 [0.51] mg/dL). Applying the recalibration (derived from Deming regression) from each approach to the original measurements, the prevalence of hyperuricemia (>7 mg/dL) was 28.5% before IOR and 8.5% after IOR. Conclusion IOR is a useful method for removal of extreme outliers irrelevant to recalibrating laboratory measurements, and identifies more extraneous outliers than the standard approach. PMID:27197675

  12. Measuring Meaningful Learning in the Undergraduate Chemistry Laboratory: A National, Cross-Sectional Study

    ERIC Educational Resources Information Center

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    Research on laboratory learning points to the need to better understand what and how students learn in the undergraduate chemistry laboratory. The Meaningful Learning in the Laboratory Instrument (MLLI) was administered to general and organic chemistry students from 15 colleges and universities across the United States in order to measure the…

  13. Laboratory Studies of Vibrational Relaxation: Important Insights for Mesospheric OH

    NASA Astrophysics Data System (ADS)

    Kalogerakis, K. S.; Matsiev, D.

    2016-12-01

    The hydroxyl radical has a key role in the chemistry and energetics of the Earth's middle atmosphere. A detailed knowledge of the rate constants and relevant pathways for OH(high v) vibrational relaxation by atomic and molecular oxygen and their temperature dependence is absolutely critical for understanding mesospheric OH and extracting reliable chemical heating rates from atmospheric observations. We have developed laser-based experimental approaches to study the complex collisional energy transfer processes involving the OH radical and other relevant atmospheric species. Previous work in our laboratory indicated that the total removal rate constant for OH(v = 9) + O at room temperature is more than one order of magnitude larger than that for removal by O2. Thus, O atoms are expected to significantly influence the intensity and vibrational distribution extracted from the Meinel OH(v) emissions. We will report our most recent laboratory experiments that corroborate the aforementioned result for fast OH(v = 9) + O and provide important new insights on the mechanistic pathways involved. We will also highlight relevant atmospheric implications, including warranted revisions of current mesospheric OH models. Research supported by SRI International Internal R&D and NSF Aeronomy grant AGS-1441896. Previously supported by NASA Geospace Science grant NNX12AD09G.

  14. Direct measurements of local bed shear stress in the presence of pressure gradients

    NASA Astrophysics Data System (ADS)

    Pujara, Nimish; Liu, Philip L.-F.

    2014-07-01

    This paper describes the development of a shear plate sensor capable of directly measuring the local mean bed shear stress in small-scale and large-scale laboratory flumes. The sensor is capable of measuring bed shear stress in the range 200 Pa with an accuracy up to 1 %. Its size, 43 mm in the flow direction, is designed to be small enough to give spatially local measurements, and its bandwidth, 75 Hz, is high enough to resolve time-varying forcing. Typically, shear plate sensors are restricted to use in zero pressure gradient flows because secondary forces on the edge of the shear plate caused by pressure gradients can introduce large errors. However, by analysis of the pressure distribution at the edges of the shear plate in mild pressure gradients, we introduce a new methodology for correcting for the pressure gradient force. The developed sensor includes pressure tappings to measure the pressure gradient in the flow, and the methodology for correction is applied to obtain accurate measurements of bed shear stress under solitary waves in a small-scale wave flume. The sensor is also validated by measurements in a turbulent flat plate boundary layer in open channel flow.

  15. Flow resistance dynamics in step‐pool stream channels: 1. Large woody debris and controls on total resistance

    USGS Publications Warehouse

    Wilcox, Andrew C.; Wohl, Ellen E.

    2006-01-01

    Flow resistance dynamics in step‐pool channels were investigated through physical modeling using a laboratory flume. Variables contributing to flow resistance in step‐pool channels were manipulated in order to measure the effects of various large woody debris (LWD) configurations, steps, grains, discharge, and slope on total flow resistance. This entailed nearly 400 flume runs, organized into a series of factorial experiments. Factorial analyses of variance indicated significant two‐way and three‐way interaction effects between steps, grains, and LWD, illustrating the complexity of flow resistance in these channels. Interactions between steps and LWD resulted in substantially greater flow resistance for steps with LWD than for steps lacking LWD. LWD position contributed to these interactions, whereby LWD pieces located near the lip of steps, analogous to step‐forming debris in natural channels, increased the effective height of steps and created substantially higher flow resistance than pieces located farther upstream on step treads. Step geometry and LWD density and orientation also had highly significant effects on flow resistance. Flow resistance dynamics and the resistance effect of bed roughness configurations were strongly discharge‐dependent; discharge had both highly significant main effects on resistance and highly significant interactions with all other variables.

  16. Evaluation of mean velocity and turbulence measurements with ADCPs

    USGS Publications Warehouse

    Nystrom, E.A.; Rehmann, C.R.; Oberg, K.A.

    2007-01-01

    To test the ability of acoustic Doppler current profilers (ADCPs) to measure turbulence, profiles measured with two pulse-to-pulse coherent ADCPs in a laboratory flume were compared to profiles measured with an acoustic Doppler velocimeter, and time series measured in the acoustic beam of the ADCPs were examined. A four-beam ADCP was used at a downstream station, while a three-beam ADCP was used at a downstream station and an upstream station. At the downstream station, where the turbulence intensity was low, both ADCPs reproduced the mean velocity profile well away from the flume boundaries; errors near the boundaries were due to transducer ringing, flow disturbance, and sidelobe interference. At the upstream station, where the turbulence intensity was higher, errors in the mean velocity were large. The four-beam ADCP measured the Reynolds stress profile accurately away from the bottom boundary, and these measurements can be used to estimate shear velocity. Estimates of Reynolds stress with a three-beam ADCP and turbulent kinetic energy with both ADCPs cannot be computed without further assumptions, and they are affected by flow inhomogeneity. Neither ADCP measured integral time scales to within 60%. ?? 2007 ASCE.

  17. OB's high voltage laboratory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1966-01-01

    The January issue of Hi-Tension News provides a detailed description of the advanced surge test facilities and procedures in daily operation at the OB High Voltage Laboratory in Barberton, Ohio. Technical competences achieved in this laboratory contribute to the essential factors of design confirmation to basic studies of ehv insulation systems, conductor and hardware performance, and optimum tower construction. Known throughout the industry for authenticity of its full scale, all weather outdoor testing, OB's High Voltage Laboratory is a full-fledged participant in the NEMA-sponsored program to make testing facilities available on a cooperative basis.

  18. Depth-dependent erodibility: representing burnt soils as a two-layered cohesive/non-cohesive system

    NASA Astrophysics Data System (ADS)

    Nyman, P.; Sheridan, G. J.; Moody, J. A.; Smith, H. G.; Lane, P. N.

    2011-12-01

    Immediately after wildfire there is an abundant supply of non-cohesive ash, soil and gravel which is easily entrained by overland flow. Under these conditions the sediment flux on hillslopes can be assumed to be equal to the transport capacity of the flow. However, the supply of material is finite and at some point the hillslope could shift towards a system where entrainment is restricted by armouring and soil cohesion. In this study we test the notion that burnt hillslopes can be represented as a two-layered system of non-cohesive and cohesive soils. Using a combination of i) shear vane measurements, ii) confined hillslope flow experiments and iii) a laboratory flume, we demonstrate how erosion on burnt hillslopes primarily takes place in a distinct layer of non-cohesive soil with erosion properties that are very different to the underlying soil matrix. Shear vane measurements were taken at 5 soil depths at more than 50 points along transects in order to quantify the depth and spatial distribution of non-cohesive soil in two small (0.5 ha) and steep (30 deg) convergent basins (SE Australia) that were burnt at high severity. The measurements showed that the recently burnt hillslopes were mantled with non-cohesive soil to an average depth of 18mm and 20mm at the two sites which were situated in different geologic terrain but in similar eucalyptus dominated forests. In the hillslope flow experiments, the rapid entrainment of non-cohesive material resulted in very high sediment concentration (50-60% by volume) in the initial surge from the test area. During the flow experiments the sediment concentration decreased exponentially with time until the erosion rate reached a steady state reflecting the erodibility of the underlying cohesive soil. The formation of shallow rills and the presence of large clasts (>16cm) within the test area resulted in incomplete removal of the non-cohesive material at shear stress < 50 Ncm-2. At shear stress > 50 Ncm-2 all material was

  19. 7. Photocopy of photographca. 1927 (2 1/4 X 2 1/4' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Photocopy of photograph--ca. 1927 (2 1/4 X 2 1/4' negative) DETAIL SHOWING ADAPTATION THAT ALLOWED USE OF UPPER END OF ORIGINAL FLUME AND LOWER END JUST RECONSTRUCTED - Power Flume No. 1, Tacoma, La Plata County, CO

  20. Soil erosion under multiple time-varying rainfall events

    NASA Astrophysics Data System (ADS)

    Heng, B. C. Peter; Barry, D. Andrew; Jomaa, Seifeddine; Sander, Graham C.

    2010-05-01

    Soil erosion is a function of many factors and process interactions. An erosion event produces changes in surface soil properties such as texture and hydraulic conductivity. These changes in turn alter the erosion response to subsequent events. Laboratory-scale soil erosion studies have typically focused on single independent rainfall events with constant rainfall intensities. This study investigates the effect of multiple time-varying rainfall events on soil erosion using the EPFL erosion flume. The rainfall simulator comprises ten Veejet nozzles mounted on oscillating bars 3 m above a 6 m × 2 m flume. Spray from the nozzles is applied onto the soil surface in sweeps; rainfall intensity is thus controlled by varying the sweeping frequency. Freshly-prepared soil with a uniform slope was subjected to five rainfall events at daily intervals. In each 3-h event, rainfall intensity was ramped up linearly to a maximum of 60 mm/h and then stepped down to zero. Runoff samples were collected and analysed for particle size distribution (PSD) as well as total sediment concentration. We investigate whether there is a hysteretic relationship between sediment concentration and discharge within each event and how this relationship changes from event to event. Trends in the PSD of the eroded sediment are discussed and correlated with changes in sediment concentration. Close-up imagery of the soil surface following each event highlight changes in surface soil structure with time. This study enhances our understanding of erosion processes in the field, with corresponding implications for soil erosion modelling.

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