Planning Guide for Fish Passage at Pittsburgh District Dams

Science.gov (United States)

2013-08-01

attracted to a downstream flow at the entrance gate of the lift. 2) Immigrants pass around a moveable crowder that, when engaged, forces fish into the...might influence fish passage over a large number of sites. REFERENCES Bailey, M. M., J. J. Isely, and W. C. Bridges , Jr. 2004. Movement and

Fish Passage Center : Fish Passage Center of the Columbia Basin Fish and Wildlife Authority; Annual report 1998

International Nuclear Information System (INIS)

DeHart, Michele

1999-01-01

The 1998 operations of the Columbia and Snake rivers system illustrated that there was potential flexibility in the operation of the hydrosystem to improve fish passage for juvenile salmon and increase the degree to which the NMS Biological Opinion measures could have been implemented successfully. This additional flexibility was not exercised. Some measures of the Biological Opinion were not implemented. The 1998 operation showed that the Hells Canyon Complex, operation, the Upper Snake River operation and Non-treaty storage operation could have provided flexibility to meet early spring and later summer flows

Can north american fish passage tools work for South american migratory fishes?

Directory of Open Access Journals (Sweden)

Claudio Rafael Mariano Baigún

Full Text Available In North America, the Numerical Fish Surrogate (NFS is used to design fish bypass systems for emigrating juvenile salmon as they migrate from hatchery outfalls and rearing habitats to adult habitat in the oceans. The NFS is constructed of three linked modules: 1 a computational fluid dynamics model describes the complex flow fields upstream of dams at a scale sufficiently resolved to analyze, understand and forecast fish movement, 2 a particle tracking model interpolates hydraulic information from the fixed nodes of the computational fluid model mesh to multiple locations relevant to migrating fish, and 3 a behavior model simulates the cognition and behavior of individual fish in response to the fluid dynamics predicted by the computational fluid dynamics model. These three modules together create a virtual reality where virtual fish exhibit realistic dam approach behaviors and can be counted at dam exits in ways similar to the real world. Once calibrated and validated with measured fish movement and passage data, the NFS can accurately predict fish passage proportions with sufficient precision to allow engineers to select one optimum alternative from among many competing structural or operational bypass alternatives. Although South American fish species are different from North American species, it is likely that the basic computational architecture and numerical methods of the NFS can be used for fish conservation in South America. Consequently, the extensive investment made in the creation of the NFS need not be duplicated in South America. However, its use in South America will require that the behavioral response of the continent's unique fishes to hydrodynamic cues must be described, codified and tested before the NFS can be used to conserve fishes by helping design efficient South American bypass systems. To this end, we identify studies that could be used to describe the movement behavior of South American fishes of sufficient detail

Walla Walla River Fish Passage Operations Project : Annual Progress Report October 2007 - September 2008.

Energy Technology Data Exchange (ETDEWEB)

Bronson, James P.; Duke, Bill; Loffink, Ken

2008-12-30

In the late 1990s, the Confederated Tribes of the Umatilla Indian Reservation, Oregon Department of Fish and Wildlife, and Washington Department of Fish and Wildlife, along with many other agencies, began implementing fisheries restoration activities in the Walla Walla Basin. An integral part of these efforts is to alleviate the inadequate fish migration conditions in the basin. Migration concerns are being addressed by removing diversion structures, constructing fish passage facilities, implementing minimum instream flow requirements, and providing trap and haul efforts when needed. The objective of the Walla Walla River Fish Passage Operations Project is to increase the survival of migrating adult and juvenile salmonids in the Walla Walla River basin. The project is responsible for coordinating operation and maintenance of ladders, screen sites, bypasses, trap facilities, and transportation equipment. In addition, the project provides technical input on passage and trapping facility design, operation, and criteria. Operation of the various passage facilities and passage criteria guidelines are outlined in an annual operations plan that the project develops. Beginning in March of 2007, two work elements from the Walla Walla Fish Passage Operations Project were transferred to other projects. The work element Enumeration of Adult Migration at Nursery Bridge Dam is now conducted under the Walla Walla Basin Natural Production Monitoring and Evaluation Project and the work element Provide Transportation Assistance is conducted under the Umatilla Satellite Facilities Operation and Maintenance Project. Details of these activities can be found in those project's respective annual reports.

Effect of stress on turbine fish passage mortality estimates

International Nuclear Information System (INIS)

Ruggles, C.P.

1993-01-01

Tests were conducted with juvenile alewife to determine the effects of four experimental protocols upon turbine fish passage mortality estimates. Three protocols determined the effect of cumulative stresses upon fish, while the fourth determined the effect of long range truck transportation prior to release into the penstock or tailrace. The wide range in results were attributed to the presence or absence of additional stress factors associated with the experiments. For instance, fish may survive passage through a turbine, or non-turbine related stresses imposed by the investigator; however, when both are imposed, the cumulative stresses may be lethal. The impact of protocol stress on turbine mortality estimates becomes almost exponential after control mortality exceeds 10%. Valid turbine related mortalities may be determined only after stresses associated with experimental protocol are adequately reduced. This is usually indicated by a control mortality of less than 10%. 14 refs., 5 figs., 6 tabs

A new technique for assessing fish passage survival at hydro power stations

International Nuclear Information System (INIS)

Heisey, P.G.; Mathur, D.; D'Allesandro, L.

1993-01-01

The HI-Z Turb'N Tag recovery method is presented as a new technique that has been successfully used at ten hydropower stations to determine turbine or spillway passage survival of fish. According to this technique, fish are tagged with the Turb'N Tag, which is pear-shaped, made of inflatable latex, and ca 35 mm long and 13 mm wide. The tag is designed to inflate after passage through the turbine, where it then floats the fish to the surface where it can be easily spotted and netted. One tag is sufficient to retrieve fish less than 18 cm long, while three tags may be needed for fish longer than 30 cm. In tests, fish were recovered in under 10 minutes from the tailrace after being tagged and released into a turbine. The tag allowed over 90% recovery of fish in most tests. The technique had minimal effect on the well-being of both hardy and sensitive species and provided an opportunity to examine recovered fish for injuries and retain them up to 72 h to assess possible delayed effects. The technique overcomes most of the logistical problems associated with conventional methods (netting, radio telemetry, mass mark-recapture) to determine turbine passage survival. The technique can also be used to assess effects of spill and fish bypass structures. 9 refs., 2 figs., 1 tab

Environmental mitigation at hydroelectric projects. Volume 2, Benefits and costs of fish passage and protection

Energy Technology Data Exchange (ETDEWEB)

Francfort, J.E.; Rinehart, B.N.; Sommers, G.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Cada, G.F.; Jones, D.W. [Oak Ridge National Lab., TN (United States); Dauble, D.D. [Pacific Northwest Lab., Richland, WA (United States); Hunt, R.T. [Hunt (Richard) Associates, Inc., Concord, NH (United States); Costello, R.J. [Northwest Water Resources Advisory Services (United States)

1994-01-01

This study examines envirorunental mitigation practices that provide upstream and downstream fish passage and protection at hydroelectric projects. The study includes a survey of fish passage and protection mitigation practices at 1,825 hydroelectric plants regulated by the Federal Energy Regulatory Commission (FERC) to determine frequencies of occurrence, temporal trends, and regional practices based on FERC regions. The study also describes, in general terms, the fish passage/protection mitigation costs at 50 non-Federal hydroelectric projects. Sixteen case studies are used to examine in detail the benefits and costs of fish passage and protection. The 16 case studies include 15 FERC licensed or exempted hydroelectric projects and one Federally-owned and-operated hydroelectric project. The 16 hydroelectric projects are located in 12 states and range in capacity from 400 kilowatts to 840 megawatts. The fish passage and protection mitigation methods at the case studies include fish ladders and lifts, an Eicher screen, spill flows, airburst-cleaned inclined and cylindrical wedgewire screens, vertical barrier screens, and submerged traveling screens. The costs, benefits, monitoring methods, and operating characteristics of these and other mitigation methods used at the 16 case studies are examined.

Walla Walla River Fish Passage Operations Program, 2003-2004 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Bronson, James P. (Confederated Tribes of the Umatilla Indian Reservation, Department of Natural Resources, Pendleton, OR)

2004-12-01

In the late 1990s, the Confederated Tribes of the Umatilla Indian Reservation, Oregon Department of Fish and Wildlife, and Washington Department of Fish and Wildlife, along with many other agencies, began implementing fisheries restoration activities in the Walla Walla Basin. An integral part of these efforts is to alleviate the inadequate fish migration conditions in the basin. The migration concerns are being addressed by removing diversion structures, constructing fish passage facilities, implementing minimum instream flow requirements, and providing trap and haul efforts when needed. The objective of the Walla Walla River Fish Passage Operations Project is to increase the survival of migrating adult and juvenile salmonids in the Walla Walla River basin. The project is responsible for coordinating operation and maintenance of ladders, screen sites, bypasses, trap facilities, and transportation equipment. In addition, the project provides technical input on passage criteria and passage and trapping facility design and operation. Operation of the various passage facilities and passage criteria guidelines are outlined in an annual operations plan that the project develops. During the 2003-2004 project year, there were 379 adult summer steelhead (Oncorhynchus mykiss), 36 adult bull trout (Salvelinus confluentus); 108 adult and 3 jack spring chinook (O. tshawytscha) enumerated at the Nursery Bridge Dam fishway video counting window between December 21, 2003, and June 30, 2004. Summer steelhead and spring chinook were observed moving upstream while bull trout were observed moving both upstream and downstream of the facility. In addition, the old ladder trap was operated by the WWBNPME project in order to radio tag spring chinook adults. A total of 2 adult summer steelhead, 4 bull trout, and 23 adult spring chinook were enumerated at the west ladder at Nursery Bridge Dam during the trapping operations between May 6 and May 23, 2004. Operation of the Little Walla Walla

Influence of seasonal, diel, lunar, and other environmental factors on upstream fish passage in the igarapava fish ladder, Brazil

Science.gov (United States)

Bizzotto, P.M.; Godinho, Alexandre L.; Vono, V.; Kynard, B.; Godinho, Hugo P.

2009-01-01

Upstream fish passage was evaluated during 12 months in the vertical-slot Igarapava Fish Ladder constructed around Igarapava Dam, in the heavily dammed Grande River, Southeast Brazil. A video monitoring system was used to observe 61,621 fish that passed the ladder, of which 93.5% were identified to 15 taxa. Among the migratory species, the most abundant were Pimelodus maculatus (33.6% of all fish), Leporinus octofasciatus (31.4%), Leporinus friderici (4.5%), and Prochilodus lineatus (3.1%). Seven taxa were classified as nonmigratory, and of these taxa, the small Bryconamericus stramineus was the most abundant (12.7%) of all fishes. Passage of the 'nonmigratory' taxa upstream in the ladder shows they are migratory in this system and have a strong behavioural drive to move to upstream habitat. Passage of most taxa had a strong seasonal pattern. While some species passed primarily during the day, others showed a distinct nocturnal pattern. Lunar phase and water temperature also strongly affected passage of some taxa. Rainfall and dam discharge had a small or null influence on most taxa; perhaps due to the fairly small catchment area of the reservoir and the highly regulated discharge at Igarapava Dam. ?? 2009 John Wiley & Sons A/S.

Downstream passage of fish larvae and eggs through a small-sized reservoir, Mucuri river, Brazil

Directory of Open Access Journals (Sweden)

Paulo S. Pompeu

2011-12-01

Full Text Available In South America, one important symptom of the failure of fish passages to sustain fish migratory recruitment is the inability of eggs and larvae to reach the nurseries. This is especially so when the breeding areas are located upstream of a reservoir, and the floodplain is downstream of the dam. Therefore, the transport of fish larvae and eggs across reservoir barriers is a key factor in the development of effective conservation strategies. In this paper, we evaluate the potential for migratory fish larvae and egg transportation across a small size reservoir in eastern Brazil. We sampled fish daily between 15th October 2002 and 15th February 2003 (spawning period in the Mucuri River, immediately upstream of the reservoir and downstream of the Santa Clara Power Plant dam. Our study was the first to indicate the possibility of successful larval passage through the reservoir of a hydroelectric reservoir and dam in South America, and showed that the passage of migratory fish larvae was associated significantly with residence time of water in the reservoir. The relatively short water residence time and elevated turbidity of the Santa Clara's reservoir waters during the rainy season certainly contributed to the successful passage, and can be considered as key factors for a priori evaluations of the feasibility of a downstream larval passage.

Fish movement ecology in high gradient headwater streams: Its relevance to fish passage restoration through stream culvert barriers

Science.gov (United States)

Hoffman, Robert L.; Dunham, Jason B.

2007-01-01

Restoration of fish passage through culvert barriers has emerged as a major issue in the Pacific Northwest and nationwide, in part, because of their potential influence on fish movement. Movement is an essential mechanism by which mobile animals acquire the resources necessary for the successful completion of their life-cycles. In this report, we provide a brief review of some essential characteristics of animal movement and examples from a focal group of fishes in Washington State: salmon, trout, and char. We begin by outlining some basic characteristics of animal movement and then apply that foundation to the case of salmonid fishes. Next we consider the consequences of disrupting fish movement with human-constructed barriers, such as culverts. Finally, this body of evidence is summarized, and we propose a short list of what we view as high priority information needs to support more effective restoration of fish passage through culverts.

Comparative Study of Barotrauma Risk during Fish Passage through Kaplan Turbines

Energy Technology Data Exchange (ETDEWEB)

Richmond, Marshall C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Hydrology Group; Romero-Gomez, Pedro [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Hydrology Group; Serkowski, John A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Hydrology Group; Rakowski, Cynthia L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Hydrology Group; Graf, Michael J. [Voith Hydro, York, PA (United States)

2015-10-01

Rapid pressure changes in hydroelectric turbine flows can cause barotrauma that can be hazardous to the passage of fish, in particular migratory juvenile salmonids. Although numerous laboratory tests have evaluated the effect of rapid decompression in fish species of relevance, numerical modeling studies offer the advantage of predicting, for new turbine designs, the potential risks of mortality and injury from rapid pressure change during turbine passage. However, rapid pressure change is only one of several hydraulic risks encountered by fish during turbine passage in addition to blade strike, shear, and turbulence. To better understand the role of rapid pressure changes, the present work focuses on the application of a computational fluid dynamics based method for evaluating the risk of pressure-related mortality to fish passing through an early 1960s era original hydroelectric Kaplan turbine at Wanapum Dam (Columbia River, Washington), and a modern advanced Kaplan turbine installed in 2005. The results show that the modeling approach acceptably reproduced the nadir pressure distributions compared to field data previously collected at the site using an autonomous sensor. Our findings show that the new advanced-design unit performs better, in terms of reduced barotrauma risk to fish from exposure to low pressures, than the original turbine unit. The outcomes allow for comparative analyses of turbine designs and operations prior to installation, an advantage that can potentially be integrated in the process of designing new turbine units to achieve superior environmental performance. Overall, the results show that modern turbine designs can achieve the multiple objectives of increasing power generation, lowering cavitation potential, and reducing barotrauma risks to passing fish.

Evaluation of Fish Passage at Whitewater Parks Using 2D and 3D Hydraulic Modeling

Science.gov (United States)

Hardee, T.; Nelson, P. A.; Kondratieff, M.; Bledsoe, B. P.

2016-12-01

In-stream whitewater parks (WWPs) are increasingly popular recreational amenities that typically create waves by constricting flow through a chute to increase velocities and form a hydraulic jump. However, the hydraulic conditions these structures create can limit longitudinal habitat connectivity and potentially inhibit upstream fish migration, especially of native fishes. An improved understanding of the fundamental hydraulic processes and potential environmental effects of whitewater parks is needed to inform management decisions about Recreational In-Channel Diversions (RICDs). Here, we use hydraulic models to compute a continuous and spatially explicit description of velocity and depth along potential fish swimming paths in the flow field, and the ensemble of potential paths are compared to fish swimming performance data to predict fish passage via logistic regression analysis. While 3d models have been shown to accurately predict trout movement through WWP structures, 2d methods can provide a more cost-effective and manager-friendly approach to assessing the effects of similar hydraulic structures on fish passage when 3d analysis in not feasible. Here, we use 2d models to examine the hydraulics in several WWP structures on the North Fork of the St. Vrain River at Lyons, Colorado, and we compare these model results to fish passage predictions from a 3d model. Our analysis establishes a foundation for a practical, transferable and physically-rigorous 2d modeling approach for mechanistically evaluating the effects of hydraulic structures on fish passage.

Experimental investigation of fish downstream passage and turbine related fish mortality at an innovative hydro power setup

International Nuclear Information System (INIS)

Geiger, Franz; Cuchet, Mathilde; Rutschmann, Peter

2016-01-01

The fish downstream passage of small fish at the innovative TUM hydro shaft power plant concept was investigated experimentally. The behavior of 1974 inserted individuals of brown trout, grayling, barbel, minnow and bullhead of 45 mm to 220 mm body length was observed in a fully functional test setup which included a 35 kW Kaplan turbine and a horizontal screen with 20 mm bar clearance. The 24 h tests were conducted under nature like conditions whereas the laboratory environment also enabled targeted hydraulic situations and modifications of the bypass during the test series. A recapture rate of the fish of 99% and a subsequent 96 h observation period yielded detailed information about the migration behavior and instant as well as long term mortality. The results reveal the actual passage distribution of small fish between bypass and turbine and the turbine related injury and mortality rates in dependency of fish species, fish length, turbine discharge and bypass arrangement. General trends as well as species specific particularities could be deduced. The work confirms the suitability of the employed experimental approach and the ecological potential of the investigated hydro power plant concept. The behavioral barrier effect of the screen on small fish and the necessary of appropriate downstream migration corridor were proved and quantified. (authors)

Time-to-event analysis as a framework for quantifying fish passage performance: Chapter 9.1

Science.gov (United States)

Castro-Santos, Theodore R.; Perry, Russell W.; Adams, Noah S.; Beeman, John W.; Eiler, John H.

2012-01-01

Fish passage is the result of a sequence of processes, whereby fish must approach, enter, and pass a structure. Each of these processes takes time, and fishway performance is best quantified in terms of the rates at which each process is completed. Optimal performance is achieved by maximizing the rates of approach, entry, and passage through safe and desirable routes. Sometimes, however, it is necessary to reduce rates of passage through less desirable routes in order to increase proportions passing through the preferred route. Effectiveness of operational or structural modifications for achieving either of these goals is best quantified by applying time-to-event analysis, commonly known as survival analysis methods, to telemetry data. This set of techniques allows for accurate estimation of passage rates and covariate effects on those rates. Importantly, it allows researchers to quantify rates that vary over time, as well as the effects of covariates that also vary over time. Finally, these methods are able to control for competing risks, i.e., the presence of alternate passage routes, failure to pass, or other fates that remove fish from the pool of candidates available to pass through a particular route. In this chapter, we present a model simulation of telemetered fish passing a hydroelectric dam, and provide step-by-step guidance and rationales for performing time-to-event analysis on the resulting data. We demonstrate how this approach removes bias from performance estimates that can result from using methods that focus only on proportions passing each route. Time-to-event analysis, coupled with multinomial models for measuring survival, provides a comprehensive set of techniques for quantifying fish passage, and a framework from which performance among different sites can be better understood.

Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2003 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

DeHart, Michele (Columbia Basin Fish and Wildlife Authority, Fish Passage Center, Portland, OR)

2004-09-01

The runoff volumes in 2003 were below average for the January to July period above Lower Granite Dam (79%) and The Dalles Dam (82%). The year 2003 hydrosystem operations and runoff conditions resulted in flows that met the spring seasonal Biological Opinion flow objectives at Lower Granite Dam, McNary Dam and Priest Rapids Dam. However, summer seasonal flows at Lower Granite Dam and McNary Dam were considerably below the Biological Opinion objectives of 50.7 Kcfs at Lower Granite Dam and 2000 Kcfs at McNary Dam. Actual summer seasonal flows were just 32.3 Kcfs and 135.5 Kcfs, respectively. In most instances spill was provided as described by the Biological Opinion program for fish passage, within the constraints of the State waivers for total dissolved gas supersaturation levels. Spill was altered during spill testing and most notably during the month of August at Ice Harbor dam. At this project spill was modified from a 24-hour program to a 12-hour nightly spill period pending the evaluation of studies being conducted in-season. Spill was not returned to full implementation of the Biological Opinion levels even after data showed that spillway passage had the highest associated fish survival. This experience demonstrated the difficulty of managing the hydrosystem for fish passage based on preliminary data and data collected in-season. Increased hatchery releases and higher wild fish production resulted in a population of yearling chinook at Lower Granite Dam being one of the highest observed in recent years. However, the increased hatchery production may have been offset to some extent by decreased survival from release to Lower Granite Dam as suggested by the lower than average survival observed for the PIT tagged trap released fish to Lower Monumental Dam. Travel times were also longer for hatchery spring chinook compared to recent past years. The short duration of high flows that occurred in the Lower Snake River was too late for yearling chinook, but likely was

The Application of Traits-Based Assessment Approaches to Estimate the Effects of Hydroelectric Turbine Passage on Fish Populations

Energy Technology Data Exchange (ETDEWEB)

Cada, Glenn F [ORNL; Schweizer, Peter E [ORNL

2012-04-01

One of the most important environmental issues facing the hydropower industry is the adverse impact of hydroelectric projects on downstream fish passage. Fish that migrate long distances as part of their life cycle include not only important diadromous species (such as salmon, shads, and eels) but also strictly freshwater species. The hydropower reservoirs that downstream-moving fish encounter differ greatly from free-flowing rivers. Many of the environmental changes that occur in a reservoir (altered water temperature and transparency, decreased flow velocities, increased predation) can reduce survival. Upon reaching the dam, downstream-migrating fish may suffer increased mortality as they pass through the turbines, spillways and other bypasses, or turbulent tailraces. Downstream from the dam, insufficient environmental flow releases may slow downstream fish passage rates or decrease survival. There is a need to refine our understanding of the relative importance of causative factors that contribute to turbine passage mortality (e.g., strike, pressure changes, turbulence) so that turbine design efforts can focus on mitigating the most damaging components. Further, present knowledge of the effectiveness of turbine improvements is based on studies of only a few species (mainly salmon and American shad). These data may not be representative of turbine passage effects for the hundreds of other fish species that are susceptible to downstream passage at hydroelectric projects. For example, there are over 900 species of fish in the United States. In Brazil there are an estimated 3,000 freshwater fish species, of which 30% are believed to be migratory (Viana et al. 2011). Worldwide, there are some 14,000 freshwater fish species (Magurran 2009), of which significant numbers are susceptible to hydropower impacts. By comparison, in a compilation of fish entrainment and turbine survival studies from over 100 hydroelectric projects in the United States, Winchell et al. (2000

Fish passage hydroelectric power plant Linne, Netherlands. Didson measurements; Vispassage waterkrachtcentrale Linne. Didson metingen

Energy Technology Data Exchange (ETDEWEB)

Van Keeken, O.A.; Griffioen, A.B. [Institute for Marine Resources and Ecosystem Studies IMARES, Wageningen UR, IJmuiden (Netherlands)

2011-11-15

The hydroelectric power plant in the Dutch Maas River near Linne has a fish deflection and passage system. For this study, two evenings in the months of August and September 2011 were dedicated to examining the extent to which fish approached and used the fish passage system. To establish the swimming behavior of the fish, a high-resolution sonar (DIDSON) was used, which generates moving images of fish in turbid waters, to study their behavior. [Dutch] Bij de waterkrachtcentrale in de Maas bij Linne is een visafweer- en geleidingssysteem aangelegd. In deze studie werd op twee avonden verdeeld over de maanden augustus en september 2011 gekeken in hoeverre vissen het visgeleidingssysteem benaderden en gebruikten. Voor het vaststellen van het zwemgedrag van de vissen is gebruik gemaakt van de DIDSON, een hoge resolutie sonar waarmee bewegende beelden kunnen worden gemaakt van vis in troebel water om het gedrag te bestuderen.

A computational fluid dynamics modeling study of guide walls for downstream fish passage

Science.gov (United States)

Mulligan, Kevin; Towler, Brett; Haro, Alexander J.; Ahlfeld, David P.

2017-01-01

A partial-depth, impermeable guidance structure (or guide wall) for downstream fish passage is typically constructed as a series of panels attached to a floating boom and anchored across a water body (e.g. river channel, reservoir, or power canal). The downstream terminus of the wall is generally located nearby to a fish bypass structure. If guidance is successful, the fish will avoid entrainment in a dangerous intake structure (i.e. turbine intakes) while passing from the headpond to the tailwater of a hydroelectric facility through a safer passage route (i.e. the bypass). The goal of this study is to determine the combination of guide wall design parameters that will most likely increase the chance of surface-oriented fish being successfully guided to the bypass. To evaluate the flow field immediately upstream of a guide wall, a parameterized computational fluid dynamics model of an idealized power canal was constructed in © ANSYS Fluent v 14.5 (ANSYS Inc., 2012). The design parameters investigated were the angle and depth of the guide wall and the average approach velocity in the power canal. Results call attention to the importance of the downward to sweeping flow ratio and demonstrate how a change in guide wall depth and angle can affect this important hydraulic cue to out-migrating fish. The key findings indicate that a guide wall set at a small angle (15° is the minimum in this study) and deep enough such that sweeping flow dominant conditions prevail within the expected vertical distribution of fish approaching the structure will produce hydraulic conditions that are more likely to result in effective passage.

A comparison of metrics to evaluate the effects of hydro-facility passage stressors on fish

Energy Technology Data Exchange (ETDEWEB)

Colotelo, Alison H.; Goldman, Amy E.; Wagner, Katie A.; Brown, Richard S.; Deng, Z. Daniel; Richmond, Marshall C.

2017-03-01

Hydropower is the most common form of renewable energy, and countries worldwide are considering expanding hydropower to new areas. One of the challenges of hydropower deployment is mitigation of the environmental impacts including water quality, habitat alterations, and ecosystem connectivity. For fish species that inhabit river systems with hydropower facilities, passage through the facility to access spawning and rearing habitats can be particularly challenging. Fish moving downstream through a hydro-facility can be exposed to a number of stressors (e.g., rapid decompression, shear forces, blade strike and collision, and turbulence), which can all affect fish survival in direct and indirect ways. Many studies have investigated the effects of hydro-turbine passage on fish; however, the comparability among studies is limited by variation in the metrics and biological endpoints used. Future studies investigating the effects of hydro-turbine passage should focus on using metrics and endpoints that are easily comparable. This review summarizes four categories of metrics that are used in fisheries research and have application to hydro-turbine passage (i.e., mortality, injury, molecular metrics, behavior) and evaluates them based on several criteria (i.e., resources needed, invasiveness, comparability among stressors and species, and diagnostic properties). Additionally, these comparisons are put into context of study setting (i.e., laboratory vs. field). Overall, injury and molecular metrics are ideal for studies in which there is a need to understand the mechanisms of effect, whereas behavior and mortality metrics provide information on the whole body response of the fish. The study setting strongly influences the comparability among studies. In laboratory-based studies, stressors can be controlled by both type and magnitude, allowing for easy comparisons among studies. In contrast, field studies expose fish to realistic passage environments but the comparability is

Indirect effects of impoundment on migrating fish: temperature gradients in fish ladders slow dam passage by adult Chinook salmon and steelhead.

Directory of Open Access Journals (Sweden)

Christopher C Caudill

Full Text Available Thermal layering in reservoirs upstream from hydroelectric dams can create temperature gradients in fishways used by upstream migrating adults. In the Snake River, Washington, federally-protected adult salmonids (Oncorhynchus spp. often encounter relatively cool water in dam tailraces and lower ladder sections and warmer water in the upstream portions of ladders. Using radiotelemetry, we examined relationships between fish passage behavior and the temperature difference between the top and bottom of ladders (∆T at four dams over four years. Some spring Chinook salmon (O. tshawytscha experienced ∆T ≥ 0.5 °C. Many summer and fall Chinook salmon and summer steelhead (O. mykiss experienced ∆T ≥ 1.0 °C, and some individuals encountered ΔT > 4.0°C. As ΔT increased, migrants were consistently more likely to move down fish ladders and exit into dam tailraces, resulting in upstream passage delays that ranged from hours to days. Fish body temperatures equilibrated to ladder temperatures and often exceeded 20°C, indicating potential negative physiological and fitness effects. Collectively, the results suggest that gradients in fishway water temperatures present a migration obstacle to many anadromous migrants. Unfavorable temperature gradients may be common at reservoir-fed fish passage facilities, especially those with seasonal thermal layering or stratification. Understanding and managing thermal heterogeneity at such sites may be important for ensuring efficient upstream passage and minimizing stress for migratory, temperature-sensitive species.

Automatic system for monitoring fish passage at dams

Science.gov (United States)

Castignolles, Nathalie; Cattoen, Michel; Larinier, M.

1994-09-01

Devices called fishways or fish passes are constructed in rivers to help migratory fish get over obstacles (dams). There counting windows are used to monitor fish passage by video-based counting. Our goal is to design and construct a vision system to automate this process. Images are taken by a video camera fitted with an electronic shutter in a backlit fishway. They are stored on optical disks in real time but are processed in delayed time. Faced with high volumes of data, a compression is necessary and an electronic board has been designed to accomplish it in real time. The coding method used is based on a run description of binarized images. Then, a tracking process is implemented on a micro-computer to count the fish crossing the pass. It includes fish recognition, which is based on a Bayesian classification process. In order to reduce processing times, recognition operations (labelling, parameter extraction) are accomplished on coded images. Classification results are satisfactory and are improved by the temporal redundancy generated by the tracking process. Image processing time permits the user, on average, to process images faster than they have been stored. Thus there is no data accumulation. At the end of the processing it is possible to edit a result file, to choose a fish, view its crossing images and change its species if wrong.

Evaluation of Fish Passage Sites in the Walla Walla River Basin, 2008

Energy Technology Data Exchange (ETDEWEB)

Chamness, Mickie A. [Pacific Northwest National Laboratory

2008-08-29

In 2008, Pacific Northwest National Laboratory evaluated the Hofer Dam fish screen and provided technical assistance at two other fish passage sites as requested by the Bonneville Power Administration, the Walla Walla Watershed Council, or the Confederated Tribes of the Umatilla Indian Reservation. Evaluation of new sites such as Hofer Dam focuses on their design, construction, operation, and maintenance to determine if they effectively provide juvenile salmonids with safe passage through irrigation diversions. There were two requests for technical assistance in 2008. In the first, the Confederated Tribes of the Umatilla Indian Reservation requested an evaluation of the Nursery Bridge fish screens associated with the fish ladder on the east side of the Walla Walla River. One set of brushes that clean the screens was broken for an extended period. Underwater videography and water velocity measurements were used to determine there were no potential adverse effects on juvenile salmonids when the west set of screens was clean enough to pass water normally. A second request, received from the National Marine Fisheries Service and the Walla Walla Watershed Council, asked for evaluation of water velocities through relatively new head gates above and adjacent to the Eastside Ditch fish screens on the Walla Walla River. Water moving through the head gates and not taken for irrigation is diverted to provide water for the Nursery Bridge fish ladder on the east side of the river. Elevations used in the design of the head gates were incorrect, causing excessive flow through the head gates that closely approached or exceeded the maximum swimming burst speed of juvenile salmonids. Hofer Dam was evaluated in June 2008. PNNL researchers found that conditions at Hofer Dam will not cause impingement or entrainment of juvenile salmonids but may provide habitat for predators and lack strong sweeping flows to encourage juvenile salmonid passage downstream. Further evaluation of

Risk assessment for fish passage through small, low-head turbines

Energy Technology Data Exchange (ETDEWEB)

Turnpenny, A.W.H.; Clough, S.; Hanson, K.P.; Ramsay, R.; McEwan, D.

2000-07-01

This report summarises the findings of a study to improve the accuracy of prediction methods for fish fatalities for small-head Francis and Kaplan propeller turbine designs and gives details of computational fluid dynamic modelling to estimate pressure fluxes and shear stresses. Biological data is reviewed, and the STRIKER Excel spreadsheet model is used to predict death caused by pressure flux, shear turbulence, and blade strike. Field validation is discussed, and drawings of the Francis 1 and Kaplan 1 turbines, results of the fish passage trials, and STRIKER instructions and sample runs are presented in the appendices.

Risk assessment for fish passage through small, low-head turbines

International Nuclear Information System (INIS)

Turnpenny, A.W.H.; Clough, S.; Hanson, K.P.; Ramsay, R.; McEwan, D.

2000-01-01

This report summarises the findings of a study to improve the accuracy of prediction methods for fish fatalities for small-head Francis and Kaplan propeller turbine designs and gives details of computational fluid dynamic modelling to estimate pressure fluxes and shear stresses. Biological data is reviewed, and the STRIKER Excel spreadsheet model is used to predict death caused by pressure flux, shear turbulence, and blade strike. Field validation is discussed, and drawings of the Francis 1 and Kaplan 1 turbines, results of the fish passage trials, and STRIKER instructions and sample runs are presented in the appendices

Knowledge exchange for efficient passage of fish in the southern hemispere (KEEPFISH)

DEFF Research Database (Denmark)

Wilkes, M. A.; Aarestrup, Kim; Jepsen, Niels

The decline of freshwater fish biodiversity is proceeding at an alarming and persistent rate. Given that most fish must undertake some form of migration in order to complete their life-cycle, of particular concern is the proliferation of hydropower schemes that block migration routes, as well as ...... passage science and policy. This will be achieved through systematic review, expert consultation, ecological modelling, postgraduate training programmes, networking and stakeholder engagement using a novel combination of approaches....

Natural Propagation and Habitat Improvement, Volume 1, Oregon, Supplement B, White River Falls Fish Passage, 1983 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1984-04-01

White River Falls are located in north central Oregon approximately 25 miles south of the City of The Dalles. The project site is characterized by a series of three natural waterfalls with a combined fall of 180 ft. In the watershed above the falls are some 120 miles of mainstem habitat and an undetermined amount of tributary stream habitat that could be opened to anadromous fish, if passage is provided around the falls. The purpose of this project is to determine feasibility of passage, select a passage scheme, and design and construct passage facilities. This report provides information on possible facilities that would pass adult anadromous fish over the White River Falls. 25 references, 29 figures, 12 tables. (ACR)

Passage of north temperate fish through the Cowan Dam Denil fishway

International Nuclear Information System (INIS)

Christense, B.

1994-01-01

Fish passage through a standard Denil fishway under low tailwater conditions was studied at Cowan Dam in Saskatchewan in 1990. In 1991 and 1992, fish passage through an experimental two-level Denil fishway was studied at the same location under similar flow conditions. Six species of fish used the Cowan Dam Denil fishway in 1990: northern pike, walleye, white sucker, longnose sucker, cisco, and lake whitefish. Tag returns suggest that most fish that congregate below Cowan Dam in the spring originate in Lac Ile-a-la-Crosse 150-200 km downstream. Northern pike waited until spawning had been completed before ascending the fishway. Only 12.1% of the pike congregated below the dam are estimated to have ascended the fishway. During 1990 and 1991, the number of pike ascending the fishway appeared to decline as water velocities in the standard and two-level Denil fishways increased. Mean pike length also declined over the period of fish movement, and as water velocities in the standard Denil declined. Walleye did not appear to have any difficulty ascending the standard Denil in 1990, but they did appear to have difficulty ascending the two-level Denil in 1991. Only 29% of the white suckers that ascended the fishway did so prior to spawning. According to recaptures of tagged fish, 58.8% of white suckers present in the tailwater pool ascended the standard Denil in 1990. White suckers also appeared to be able to ascend the two-level Denil without difficulty. Of the longnose suckers, 98% ascended the fishway prior to spawning in 1990, and appeared to ascend both the standard and two-level fishways without obvious delay or difficulty. Only small numbers of cisco and lake whitefish utilized the standard Denil fishway in 1990. 68 refs., 56 figs., 24 tabs

Upstream movements of Atlantic Salmon in the Lower Penobscot River, Maine following two dam removals and fish passage modifications

Science.gov (United States)

Izzo, Lisa K.; Maynard, George A.; Zydlewski, Joseph D.

2016-01-01

The Penobscot River Restoration Project (PRRP), to be completed in 2016, involved an extensive plan of dam removal, increases in hydroelectric capacity, and fish passage modifications to increase habitat access for diadromous species. As part of the PRRP, Great Works and Veazie dams were removed, making Milford Dam the first impediment to federally endangered Atlantic Salmon Salmo salar. Upstream habitat access for Atlantic Salmon is dependent upon successful and timely passage at Milford Dam because nearly all suitable spawning habitat is located upstream. In 2014 and 2015, a total of 73 adult salmon were radio-tagged to track their upstream movements through the Penobscot River to assess potential delays at (1) the dam remnants, (2) the confluence of the Stillwater Branch and the main stem of the Penobscot River below the impassable Orono Dam, and (3) the Milford Dam fish lift (installed in 2014). Movement rates through the dam remnants and the Stillwater confluence were comparable to open river reaches. Passage efficiency of the fish lift was high in both years (95% and 100%). However, fish experienced long delays at Milford Dam, with approximately one-third of fish taking more than a week to pass in each year, well below the Federal Energy Regulatory Commission passage standard of 95% within 48 h. Telemetry indicates most fish locate the fishway entrance within 5 h of arrival and were observed at the entrance at all hours of the day. These data indicate that overall transit times through the lower river were comparable to reported movement rates prior to changes to the Penobscot River due to the substantial delays seen at Milford Dam. The results of this study show that while adult Atlantic Salmon locate the new fish lift entrance quickly, passage of these fish was significantly delayed under 2014–2015 operations.

Effects of grade control structures on fish passage, biological assemblages, and hydraulic environments in western Iowa streams: a multidisciplinary review

Science.gov (United States)

Thomas, J.T.; Culler, M.E.; Dermisis, D.C.; Pierce, Clay; Papanicolaou, A.N.; Stewart, T.W.; Larson, C.J.

2011-01-01

Land use changes and channelization of streams in the deep loess region of western Iowa have led to stream channel incision, altered flow regimes, increased sediment inputs, decreased habitat diversity and reduced lateral connectivity of streams and floodplains. Grade control structures (GCSs) are built in streams to prevent further erosion, protect infrastructure and reduce sediment loads. However, GCS can have a detrimental impact on fisheries and biological communities. We review three complementary biological and hydraulic studies on the effects of GCS in these streams. GCS with steep (≥1:4 rise : run) downstream slopes severely limited fish passage, but GCS with gentle slopes (≤1:15) allowed greater passage. Fish assemblages were dominated by species tolerant of degradation, and Index of Biotic Integrity (IBI) scores were indicative of fair or poor biotic integrity. More than 50% of fish species had truncated distributions. After modification of GCS to reduce slopes and permit increased passage, IBI scores increased and several species were detected further upstream than before modification. Total macroinvertebrate density, biomass and taxonomic diversity and abundance of ecologically sensitive taxa were greater at GCS than in reaches immediately upstream, downstream or ≥1 km from GCS. A hydraulic study confirmed results from fish passage studies; minimum depths and maximum current velocities at GCS with gentle slopes (≤1:15) were more likely to meet minimum criteria for catfish passage than GCS with steeper slopes. Multidisciplinary approaches such as ours will increase understanding of GCS-associated factors influencing fish passage, biological assemblage structure and other ecological relationships in streams.

Improving hydroturbine pressures to enhance salmon passage survival and recovery

Energy Technology Data Exchange (ETDEWEB)

Trumbo, Bradly A. [U.S. Army Corp. of Engineers, Walla Walla, WA (United States); Ahmann, Martin L. [U.S. Army Corp. of Engineers, Walla Walla, WA (United States); Renholods, Jon F. [U.S. Army Corp. of Engineers, Walla Walla, WA (United States); Brown, Richard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Colotelo, Alison H. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Deng, Zhiqun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2013-12-12

This paper provides an overview of turbine pressure data collection and barotrauma studies relative to fish passage through large Kaplan turbines and how this information may be applied to safer fish passage through turbines. The specific objectives are to 1) discuss turbine pressures defined by Sensor Fish releases; 2) discuss what has been learned about pressure effects on fish and the factors influencing barotrauma associated with simulated turbine passage; 3) elucidate data gaps associated with fish behavior and passage that influence barotrauma during turbine passage; 4) discuss how the results of these studies have led to turbine design criteria for safer fish passage; and 5) relate this information to salmon recovery efforts and safer fish passage for Atlantic and Pacific salmonids.

Hungry Horse Dam fisheries mitigation program: Fish passage and habitat improvement in the Upper Flathead River basin

International Nuclear Information System (INIS)

Knotek, W.L.; Deleray, M.; Marotz, B.

1997-08-01

In the past 50 years, dramatic changes have occurred in the Flathead Lake and River system. Degradation of fishery resources has been evident, in part due to deterioration of aquatic habitat and introduction of non-endemic fish and invertebrate species. Habitat loss has been attributed to many factors including the construction and operation of Hungry Horse Dam, unsound land use practices, urban development, and other anthropogenic and natural disturbances. Fish migration has also been limited by barriers such as dams and impassible culverts. Cumulatively, these factors have contributed to declines in the distribution and abundance of native fish populations. Recovery of fish populations requires that a watershed approach be developed that incorporates long-term aquatic habitat needs and promotes sound land use practices and cooperation among natural resource management agencies. In this document, the authors (1) describe completed and ongoing habitat improvement and fish passage activities under the Hungry Horse Fisheries Mitigation Program, (2) describe recently identified projects that are in the planning stage, and (3) develop a framework for identifying prioritizing, implementing, and evaluating future fish habitat improvement and passage projects

Fish as vectors in the dispersal of Bythotrephes cederstroemi: Diapausing eggs survive passage through the gut

Science.gov (United States)

Jarnagin, S.T.; Swan, B.K.; Kerfoot, W.C.

2000-01-01

1. Bythotrephes cederstroemi (Crustacea: Onychopoda: Cercopagidae) is an introduced invertebrate predator currently spreading through the Laurentian Great Lakes region of North America. We examined a previously unsuspected way in which B. cederstroemi may be dispersed by fish by their consumption of diapausing eggs. 2. Ninety-four percentage of the mature B. cederstroemi diapausing eggs consumed by fish were egested apparently intact. This proportion is considerably above previous estimates for the ephippial eggs of Daphnia. The hatching success of diapausing eggs was compared among four categories: (a) eggs released naturally by B. cederstroemi (control, 73% hatched (b) eggs released during 'stressful confinement' (46% hatched) (c) eggs dissected from dead females (13% hatched) and (d) eggs recovered from faecal pellets following consumption by fish (viable gut passage experiment, 41% hatched). 3. Samples of small fish and B. cederstroemi were collected simultaneously. Examination of gut contents revealed that fish contained B. cederstroemi diapausing eggs and that B. cederstroemi bearing resting eggs were consumed selectively over those without eggs. Moreover, fish selected B. cederstroemi bearing mature rather than immature diapausing eggs. 4. The fact that diapausing eggs survive gut passage is important for the dispersal of B. cederstroemi. Fish often move between the pelagic and littoral zones of lakes and may thus disperse diapausing eggs widely. Fish may also move between lakes connected by river systems and can be caught and passively dispersed by anglers or piscivorous birds. Our results demonstrate the potential for fish to act as vectors in the spread of B. cederstroemi.

Fish passage assessment of an advanced hydropower turbine and conventional turbine using blade-strike modeling

Energy Technology Data Exchange (ETDEWEB)

Deng, Z.; Carlson, T. J.; Dauble, D. D.; Ploskey, G. R. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States)

2011-07-01

Hydropower is the largest renewable energy source in the world. However, in the Columbia and Snake River basins, several species of Pacific salmon and steelhead have been listed for protection under the Endangered Species Act due to significant declines of fish population. Dam operators and design engineers are thus faced with the task of making hydroelectric facilities more fish friendly through changes in hydro-turbine design and operation. Public Utility District No. 2 of Grant County, Washington, applied for relicensing from the U.S. Federal Energy Regulatory Commission to replace the 10 turbines at Wanapum Dam with advanced hydropower turbines that were designed to increase power generation and improve fish passage conditions. We applied both deterministic and stochastic blade-strike models to compare fish passage performance of the newly installed advanced turbine to an existing turbine. Modeled probabilities were compared to the results of a large-scale live-fish survival study and a Sensor Fish study under the same operational parameters. Overall, injury rates predicted by the deterministic model were higher than experimental rates of injury, while those predicted by the stochastic model were in close agreement with experimental results. Fish orientation at the time of entry into the plane of the leading edges of the turbine runner blades was an important factor contributing to uncertainty in modeled results. The advanced design turbine had slightly higher modeled injury rates than the existing turbine design; however, no statistical evidence suggested significant differences in blade-strike injuries between the two turbines, thus the hypothesis that direct fish survival rate through the advanced hydropower turbine is equal to or higher than that for fish passing through the conventional turbine could not be rejected. (authors)

Fish Passage Assessment of an Advanced Hydropower Turbine and Conventional Turbine Using Blade-Strike Modeling

Directory of Open Access Journals (Sweden)

Zhiqun Deng

2011-01-01

Full Text Available Hydropower is the largest renewable energy source in the world. However, in the Columbia and Snake River basins, several species of Pacific salmon and steelhead have been listed for protection under the Endangered Species Act due to significant declines of fish population. Dam operators and design engineers are thus faced with the task of making hydroelectric facilities more fish friendly through changes in hydro-turbine design and operation. Public Utility District No. 2 of Grant County, Washington, applied for relicensing from the U.S. Federal Energy Regulatory Commission to replace the 10 turbines at Wanapum Dam with advanced hydropower turbines that were designed to increase power generation and improve fish passage conditions. We applied both deterministic and stochastic blade-strike models to compare fish passage performance of the newly installed advanced turbine to an existing turbine. Modeled probabilities were compared to the results of a large-scale live-fish survival study and a Sensor Fish study under the same operational parameters. Overall, injury rates predicted by the deterministic model were higher than experimental rates of injury, while those predicted by the stochastic model were in close agreement with experimental results. Fish orientation at the time of entry into the plane of the leading edges of the turbine runner blades was an important factor contributing to uncertainty in modeled results. The advanced design turbine had slightly higher modeled injury rates than the existing turbine design; however, no statistical evidence suggested significant differences in blade-strike injuries between the two turbines, thus the hypothesis that direct fish survival rate through the advanced hydropower turbine is equal to or higher than that for fish passing through the conventional turbine could not be rejected.

Optimizing Hydro Power Turbines in Order to Secure the Passage of Fishes in Khuzestan province

Directory of Open Access Journals (Sweden)

Moona Mohammadi

2015-04-01

Full Text Available Nowadays,it is important to consider environmental issues,as ecological problems and their severe effect intensify in Iran,particularly in Khuzestan province.The environmental effects of hydroelectric plants are highly regarded due to their significant impact on an extensive area.The lack of safe path for fish passing through the turbines is one of these damages. In order to deal with these challenges,researchers are trying to optimize hydro power turbines.In this optimization,old runners were replaced,while conditions of fish passing through the turbines and fish survival have been improved.Considering the existence of six hydroelectric power plants in Khuzestan province,it would be possible to conduct optimization or constructing studies with a fish-friendly approach for the safe passage of fishes to slightly reduce the extent of environmental damages.

Fish Passage Center 2001 annual report.; ANNUAL

International Nuclear Information System (INIS)

Fish Passage Center

2002-01-01

Extremely poor water conditions within the Columbia River Basin along with extraordinary power market conditions created an exceptionally poor migration year for juvenile salmon and steelhead. Monthly 2001 precipitation at the Columbia above Grand Coulee, the Snake River above Ice Harbor, and the Columbia River above The Dalles was approximately 70% of average. As a result the 2001 January-July runoff volume at The Dalles was the second lowest in Columbia River recorded history. As a compounding factor to the near record low flows in 2001, California energy deregulation and the resulting volatile power market created a financial crisis for the Bonneville Power Administration (BPA). Power emergencies were first declared in the summer and winter of 2000 for brief periods of time. In February of 2001, and on April 3, the BPA declared a ''power emergency'' and suspended many of the Endangered Species Act (ESA) and Biological Opinion (Opinion) measures that addressed mainstem Columbia and Snake Rivers juvenile fish passage. The river and reservoir system was operated primarily for power generation. Power generation requirements in January through March coincidentally provided emergence and rearing flows for the Ives-Pierce Islands spawning area below Bonneville Dam. In particular, flow and spill measures to protect juvenile downstream migrant salmon and steelhead were nearly totally suspended. Spring and summer flows were below the Opinion migration target at all sites. Maximum smolt transportation was implemented instead of the Opinion in-river juvenile passage measures. On May 16, the BPA Administrator decided to implement a limited spill for fish passage at Bonneville and The Dalles dams. On May 25, a limited spill program was added at McNary and John Day dams. Spill extended to July 15. Juvenile migrants, which passed McNary Dam after May 21, experienced a noticeable, improved survival, as a benefit of spill at John Day Dam. The suspension of Biological Opinion

Synthesis of downstream fish passage information at projects owned by the U.S. Army Corps of Engineers in the Willamette River Basin, Oregon

Science.gov (United States)

Hansen, Amy C.; Kock, Tobias J.; Hansen, Gabriel S.

2017-08-07

The U.S. Army Corps of Engineers (USACE) operates the Willamette Valley Project (Project) in northwestern Oregon, which includes a series of dams, reservoirs, revetments, and fish hatcheries. Project dams were constructed during the 1950s and 1960s on rivers that supported populations of spring Chinook salmon (Oncorhynchus tshawytscha), winter steelhead (O. mykiss), and other anadromous fish species in the Willamette River Basin. These dams, and the reservoirs they created, negatively affected anadromous fish populations. Efforts are currently underway to improve passage conditions within the Project and enhance populations of anadromous fish species. Research on downstream fish passage within the Project has occurred since 1960 and these efforts are documented in numerous reports and publications. These studies are important resources to managers in the Project, so the USACE requested a synthesis of existing literature that could serve as a resource for future decision-making processes. In 2016, the U.S. Geological Survey conducted an extensive literature review on downstream fish passage studies within the Project. We identified 116 documents that described studies conducted during 1960–2016. Each of these documents were obtained, reviewed, and organized by their content to describe the state-of-knowledge within four subbasins in the Project, which include the North Santiam, South Santiam, McKenzie, and Middle Fork Willamette Rivers. In this document, we summarize key findings from various studies on downstream fish passage in the Willamette Project. Readers are advised to review specific reports of interest to insure that study methods, results, and additional considerations are fully understood.

Hungry Horse Dam Fisheries Mitigation : Fish Passage and Habitat Improvement in the Upper Flathead River Basin, 1991-1996 Progress Report.

Energy Technology Data Exchange (ETDEWEB)

Knotek, W.Ladd; Deleray, Mark; Marotz, Brian L.

1997-08-01

In the past 50 years, dramatic changes have occurred in the Flathead Lake and River system. Degradation of fishery resources has been evident, in part due to deterioration of aquatic habitat and introduction of non-endemic fish and invertebrate species. Habitat loss has been attributed to many factors including the construction and operation of Hungry Horse Dam, unsound land use practices, urban development, and other anthropogenic and natural disturbances. Fish migration has also been limited by barriers such as dams and impassible culverts. Cumulatively, these factors have contributed to declines in the distribution and abundance of native fish populations. Recovery of fish populations requires that a watershed approach be developed that incorporates long-term aquatic habitat needs and promotes sound land use practices and cooperation among natural resource management agencies. In this document, the authors (1) describe completed and ongoing habitat improvement and fish passage activities under the Hungry Horse Fisheries Mitigation Program, (2) describe recently identified projects that are in the planning stage, and (3) develop a framework for identifying prioritizing, implementing, and evaluating future fish habitat improvement and passage projects.

Fish Passage Center 2007 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

DeHart, Michele [Fish Passage Center of the Columbia Basin Fish & Wildlife Authority

2008-11-25

and McNary dams), whereas prior to 2005 spill was terminated at these projects after the spring period. In addition, the 2007 operations agreement provided regardless of flow conditions. For the first time spill for fish passage was provided in the low flow conditions that prevailed in the Snake River throughout the spring and summer migration periods. Gas bubble trauma (GBT) monitoring continued throughout the spill period. A higher incidence of rank 1, GBT signs were observed in late arriving steelhead smolts arriving after the 95% passage date had occurred. During this time dissolved gas levels were generally below the 110% water quality standard in the forebay where fish were sampled. This occurrence was due to prolonged exposure and extended travel times due to low migration flows. The 2007 migration conditions differed from any year in the historic record. The migration conditions combined low river flows in the Snake River with spill throughout the spring and summer season. The juvenile migration characteristics observed in 2007 were unique compared to past years in that high levels of 24 hour spill for fish passage were provided in low flow conditions, and with a delayed start to the smolt transportation program a smaller proportion of the total run being transported. This resulted in relatively high spring juvenile survival despite the lower flows. The seasonal spring average flow in the Snake River was 61 Kcfs much lower than the spring time average of 120 Kcfs that occurred in 2006. However juvenile steelhead survival through the Lower Granite to McNary reach in 2007 was nearly 70% which was similar to the juvenile steelhead survival seen in 2006 under higher migration flows. The low flows in the May-July period of 2007 were similar to the 2001 low flow year, yet survival for fall chinook juveniles in this period in 2007 was much higher. In 2001 the reach survival estimate for juvenile fall Chinook from Lower Granite to McNary Dam ranged from 0

Downstream fish passage guide walls: A hydraulic scale model analysis

Science.gov (United States)

Mulligan, Kevin; Towler, Brett; Haro, Alexander J.; Ahlfeld, David P.

2018-01-01

Partial-depth guide walls are used to improve passage efficiency and reduce the delay of out-migrating anadromous fish species by guiding fish to a bypass route (i.e. weir, pipe, sluice gate) that circumvents the turbine intakes, where survival is usually lower. Evaluation and monitoring studies, however, indicate a high propensity for some fish to pass underneath, rather than along, the guide walls, compromising their effectiveness. In the present study we evaluated a range of guide wall structures to identify where/if the flow field shifts from sweeping (i.e. flow direction primarily along the wall and towards the bypass) to downward-dominant. Many migratory fish species, particularly juveniles, are known to drift with the flow and/or exhibit rheotactic behaviour during their migration. When these behaviours are present, fish follow the path of the flow field. Hence, maintaining a strong sweeping velocity in relation to the downward velocity along a guide wall is essential to successful fish guidance. Nine experiments were conducted to measure the three-dimensional velocity components upstream of a scale model guide wall set at a wide range of depths and angles to flow. Results demonstrated how each guide wall configuration affected the three-dimensional velocity components, and hence the downward and sweeping velocity, along the full length of the guide wall. In general, the velocities produced in the scale model were sweeping dominant near the water surface and either downward dominant or close to the transitional depth near the bottom of the guide wall. The primary exception to this shift from sweeping do downward flow was for the minimum guide wall angle tested in this study (15°). At 15° the flow pattern was fully sweeping dominant for every cross-section, indicating that a guide wall with a relatively small angle may be more likely to produce conditions favorable to efficient guidance. A critical next step is to evaluate the behaviour of migratory fish as

Cowlitz Falls fish passage

International Nuclear Information System (INIS)

1995-09-01

The upper Cowlitz was once home to native salmon and steelhead. But the combined impacts of overharvest, farming, logging and road building hammered fish runs. And in the 1960s, a pair of hydroelectric dams blocked the migration path of ocean-returning and ocean-going fish. The lower Cowlitz still supports hatchery runs of chinook, coho and steelhead. But some 200 river miles in the upper river basin--much of it prime spawning and rearing habitat--have been virtually cut off from the ocean for over 26 years. Now the idea is to trap-and-haul salmon and steelhead both ways and bypass previously impassable obstacles in the path of anadromous fish. The plan can be summarized, for the sake of explanation, in three steps: (1) trap and haul adult fish--collect ocean-returning adult fish at the lowermost Cowlitz dam, and truck them upstream; (2) reseed--release the ripe adults above the uppermost dam, and let them spawn naturally, at the same time, supplement these runs with hatchery born fry that are reared and imprinted in ponds and net pens in the watershed; (3) trap and haul smolts--collection the new generation of young fish as they arrive at the uppermost Cowlitz dam, truck them past the three dams, and release them to continue their downstream migration to the sea. The critical part of any fish-collection system is the method of fish attraction. Scientists have to find the best combination of attraction system and screens that will guide young fish to the right spot, away from the turbine intakes. In the spring of 1994 a test was made of a prototype system of baffles and slots on the upriver face of the Cowlitz Falls Dam. The prototype worked at 90% efficiency in early tests, and it worked without the kind of expensive screening devices that have been installed on other dams. Now that the success of the attraction system has been verified, Harza engineers and consultants will design and build the appropriate collection part of the system

Behaviour and locomotor activity of a migratory catostomid during fishway passage.

Directory of Open Access Journals (Sweden)

Ana T Silva

Full Text Available Fishways have been developed to restore longitudinal connectivity in rivers. Despite their potential for aiding fish passage, fishways may represent a source of significant energetic expenditure for fish as they are highly turbulent environments. Nonetheless, our understanding of the physiological mechanisms underpinning fishway passage of fish is still limited. We examined swimming behaviour and activity of silver redhorse (Moxostoma anisurum during its upriver spawning migration in a vertical slot fishway. We used an accelerometer-derived instantaneous activity metric (overall dynamic body acceleration to estimate location-specific swimming activity. Silver redhorse demonstrated progressive increases in activity during upstream fishway passage. Moreover, location-specific passage duration decreased with an increasing number of passage attempts. Turning basins and the most upstream basin were found to delay fish passage. No relationship was found between basin-specific passage duration and activity and the respective values from previous basins. The results demonstrate that successful fishway passage requires periods of high activity. The resultant energetic expenditure may affect fitness, foraging behaviour and increase susceptibility to predation, compromising population sustainability. This study highlights the need to understand the physiological mechanisms underpinning fishway passage to improve future designs and interpretation of biological evaluations.

Fish elevator and method of elevating fish

Science.gov (United States)

Truebe, Jonathan; Drooker, Michael S.

1984-01-01

A means and method for transporting fish from a lower body of water to a higher body of water. The means comprises a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water.

Hydroacoustic Evaluation of Juvenile Salmonid Passage and Distribution at Lookout Point Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Johnson, Gary E.; Royer, Ida M.; Hughes, James S.; Fischer, Eric S.; Trott, Donna M.; Ploskey, Gene R.

2011-07-01

This report presents the results of an evaluation of juvenile salmonid passage and distribution at Lookout Point Dam (LOP) on the Middle Fork Willamette River. The study was conducted by the Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers, Portland District (USACE). The goal of the study was to provide fish passage and distribution data to support decisions on long-term measures to enhance downstream passage at LOP and others dams in USACE’s Willamette Valley Project in response to the listing of Upper Willamette River Spring Chinook salmon (Oncorhynchus tshawytscha) and Upper Willamette River steelhead (O. mykiss) as threatened under the Endangered Species Act. During the year-long study period - February 1, 2010 to January 31, 2011the objectives of the hydroacoustic evaluation of fish passage and distribution at LOP were to: 1. Estimate passage rates, run timing, horizontal distribution, and diel distribution at turbine penstock intakes for smolt-size fish. 2. Estimate passage rates, run timing and diel distribution at turbine penstock intakes for small-size fish. 3. Estimate passage rates and run timing at the regulating outlets for smolt-size fish. 4. Estimate vertical distribution of smolt-size fish in the forebay near the upstream face of the dam. The fixed-location hydroacoustic technique was used to accomplish the objectives of this study. Transducers (420 kHz) were deployed in each penstock intake, above each RO entrance, and on the dam face; a total of nine transducers (2 single-beam and 7 split-beam) were used. We summarize the findings from the hydroacoustic evaluation of juvenile salmonid passage and distribution at LOP during February 2010 through January 2011 as follows. • Fish passage rates for smolt-size fish (> ~90 mm) were highest during December-January and lowest in mid-summer through early fall. • During the entire study period, an estimated total of 142,463 fish ± 4,444 (95% confidence interval) smolt

Brook trout passage performance through culverts

Science.gov (United States)

Goerig, Elsa; Castro-Santos, Theodore R.; Bergeron, Normand

2016-01-01

Culverts can restrict access to habitat for stream-dwelling fishes. We used passive integrated transponder telemetry to quantify passage performance of >1000 wild brook trout (Salvelinus fontinalis) attempting to pass 13 culverts in Quebec under a range of hydraulic and environmental conditions. Several variables influenced passage success, including complex interactions between physiology and behavior, hydraulics, and structural characteristics. The probability of successful passage was greater through corrugated metal culverts than through smooth ones, particularly among smaller fish. Trout were also more likely to pass at warmer temperatures, but this effect diminished above 15 °C. Passage was impeded at higher flows, through culverts with steep slopes, and those with deep downstream pools. This study provides insight on factors influencing brook trout capacity to pass culverts as well as a model to estimate passage success under various conditions, with an improved resolution and accuracy over existing approaches. It also presents methods that could be used to investigate passage success of other species, with implications for connectivity of the riverscape.

Hydroacoustic Evaluation of Juvenile Salmonid Passage and Distribution at Detroit Dam, 2011

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Royer, Ida M.; Johnson, Gary E.; Ham, Kenneth D.

2012-11-15

Pacific Northwest National Laboratory evaluated juvenile salmonid passage and distribution at Detroit Dam (DET) on the North Santiam River, Oregon for the U.S. Army Corps of Engineers (USACE) to provide data to support decisions on long-term measures to enhance downstream passage at DET and others dams in USACE’s Willamette Valley Project. This study was conducted in response to regulatory requirements necessitated by the listing of Upper Willamette River Spring Chinook salmon (Oncorhynchus tshawytscha) and Upper Willamette River steelhead (O. mykiss) as threatened under the Endangered Species Act. The goal of the study was to provide information of juvenile salmonid passage and distribution at DET from February 2011 through February 2012. The results of the hydroacoustic study provide new and, in some cases, first-ever data on passage estimates, run timing, distributions, and relationships between fish passage and environmental variables at the dam. This information will inform management decisions on the design and development of surface passage and collection devices to help restore Chinook salmon populations in the North Santiam River watershed above DET. During the entire study period, an estimated total of 182,526 smolt-size fish (±4,660 fish, 95% CI) passed through turbine penstock intakes. Run timing peaked in winter and early spring months. Passage rates were highest during late fall, winter and early spring months and low during summer. Horizontal distribution for hours when both turbine units were operated simultaneously indicated Unit 2 passed almost twice as much fish as Unit 1. Diel distribution for smolt-size fish during the study period was fairly uniform, indicating fish were passing the turbines at all times of the day. A total of 5,083 smolt-size fish (± 312 fish, 95% CI) were estimated passed via the spillway when it was open between June 23 and September 27, 2011. Daily passage was low at the spillway during the June-August period, and

Migratory delay leads to reduced passage success of Atlantic salmon smolts at a hydroelectric dam

Science.gov (United States)

Nyqvist, Daniel; Greenberg, L.; Goerig, E.; Calles, O.; Bergman, E.; Ardren, William R.; Castro-Santos, Theodore R.

2017-01-01

Passage of fish through hydropower dams is associated with mortality, delay, increased energy expenditure and migratory failure for migrating fish and the need for remedial measures for both upstream and downstream migration is widely recognised. A functional fish passage must ensure safe and timely passage routes that a substantial portion of migrating fish will use. Passage solutions must address not only the number or percentage of fish that successfully pass a barrier, but also the time it takes to pass. Here, we used radiotelemetry to study the functionality of a fish bypass for downstream-migrating wild-caught and hatchery-released Atlantic salmon smolts. We used time-to-event analysis to model the influence of fish characteristics and environmental variables on the rates of a series of events associated with dam passage. Among the modelled events were approach rate to the bypass entry zone, retention rates in both the forebay and the entry zone and passage rates. Despite repeated attempts, only 65% of the tagged fish present in the forebay passed the dam. Fish passed via the bypass (33%), via spill (18%) and via turbines (15%). Discharge was positively related to approach, passage and retention rates. We did not detect any differences between wild and hatchery fish. Even though individual fish visited the forebay and the entry zone on multiple occasions, most fish passed during the first exposures to these zones. This study underscores the importance of timeliness to passage success and the usefulness of time-to-event analysis for understanding factors governing passage performance.

Synthesis of Sensor Fish Data for Assessment of Fish Passage Conditions at Turbines, Spillways, and Bypass Facilities – Phase 1: The Dalles Dam Spillway Case Study

Energy Technology Data Exchange (ETDEWEB)

Deng, Zhiqun; Serkowski, John A.; Fu, Tao; Carlson, Thomas J.; Richmond, Marshall C.

2007-12-31

This report summarizes the characterization of spillway passage conditions at The Dalles Dam in 2006 and the effort to complete a comprehensive database for data sets from The Dalles Dam spillway Sensor Fish and balloon-tagged live fish experiments. Through The Dalles Dam spillway case study, Pacific Northwest National Laboratory (PNNL) researchers evaluated the database as an efficient means for accessing and retrieving system-wide data for the U.S Army Corps of Engineers (USACE).

White River Falls Fish Passage Project, Tygh Valley, Oregon : Final Technical Report, Volume III, Appendix B, Fisheries Report; Appendix C, Engineering Alternative Evaluation; Appendix D, Benefit/Cost Analysis.

Energy Technology Data Exchange (ETDEWEB)

Oregon. Dept. of Fish and Wildlife; Mount Hood National Forest (Or.)

1985-06-01

Studies were conducted to describe current habitat conditions in the White River basin above White River Falls and to evaluate the potential to produce anadromous fish. An inventory of spawning and rearing habitats, irrigation diversions, and enhancement opportunities for anadromous fish in the White River drainage was conducted. Survival of juvenile fish at White River Falls was estimated by releasing juvenile chinook and steelhead above the falls during high and low flow periods and recapturing them below the falls in 1983 and 1984. Four alternatives to provide upstream passage for adult salmon and steelhead were developd to a predesign level. The cost of adult passage and the estimated run size of anadromous fish were used to determine the benefit/cost of the preferred alternative. Possible effects of the introduction of anadromous fish on resident fish and on nearby Oak Springs Hatchery were evaluated. This included an inventory of resident species, a genetic study of native rainbow, and the identification of fish diseases in the basin. This volume contains appendices of habitat survey data, potential production, resident fish population data, upstream passage designs, and benefit/cost calculations. (ACR)

Fish elevator and method of elevating fish

Energy Technology Data Exchange (ETDEWEB)

Truebe, J.; Drooker, M.S.

1984-02-14

A means and method are disclosed for transporting fish from a lower body of water to a higher body of water. The means comprise a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water. 6 figs.

Hydroacoustic Evaluation of Juvenile Salmonid Passage and Distribution at Lookout Point Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Johnson, Gary E.; Royer, Ida M.; Hughes, James S.; Fischer, Eric S.; Trott, Donna M.; Ploskey, Gene R.

2012-05-31

Pacific Northwest National Laboratory evaluated juvenile salmonid passage and distribution at Lookout Point Dam (LOP) on the Middle Fork Willamette River for the U.S. Army Corps of Engineers, Portland District (USACE), to provide data to support decisions on long-term measures to enhance downstream passage at LOP and others dams in USACE's Willamette Valley Project. This study was conducted in response to the listing of Upper Willamette River Spring Chinook salmon (Oncorhynchus tshawytscha) and Upper Willamette River steelhead (O. mykiss) as threatened under the Endangered Species Act. We conducted a hydroacoustic evaluation of juvenile salmonid passage and distribution at LOP during February 2010 through January 2011. Findings from this 1 year of study should be applied carefully because annual variation can be expected due to variability in adult salmon escapement, egg-to-fry and fry-to-smolt survival rates, reservoir rearing and predation, dam operations, and weather. Fish passage rates for smolt-size fish (> {approx}90 mm and < 300 mm) were highest during December-January and lowest in mid-summer through early fall. Passage peaks were also evident in early spring, early summer, and late fall. During the entire study period, an estimated total of 142,463 fish {+-} 4,444 (95% confidence interval) smolt-size fish passed through turbine penstock intakes. Of this total, 84% passed during December-January. Run timing for small-size fish ({approx}65-90 mm) peaked (702 fish) on December 18. Diel periodicity of smolt-size fish showing crepuscular peaks was evident in fish passage into turbine penstock intakes. Relatively few fish passed into the Regulating Outlets (ROs) when they were open in summer (2 fish/d) and winter (8 fish/d). Overall, when the ROs were open, RO efficiency (RO passage divided by total project passage) was 0.004. In linear regression analyses, daily fish passage (turbines and ROs combined) for smolt-size fish was significantly related to

Fish Passage Assessment: Big Canyon Creek Watershed, Technical Report 2004.

Energy Technology Data Exchange (ETDEWEB)

Christian, Richard

2004-02-01

This report presents the results of the fish passage assessment as outlined as part of the Protect and Restore the Big Canyon Creek Watershed project as detailed in the CY2003 Statement of Work (SOW). As part of the Northwest Power Planning Council's Columbia Basin Fish and Wildlife Program (FWP), this project is one of Bonneville Power Administration's (BPA) many efforts at off-site mitigation for damage to salmon and steelhead runs, their migration, and wildlife habitat caused by the construction and operation of federal hydroelectric dams on the Columbia River and its tributaries. The proposed restoration activities within the Big Canyon Creek watershed follow the watershed restoration approach mandated by the Fisheries and Watershed Program. Nez Perce Tribal Fisheries/Watershed Program vision focuses on protecting, restoring, and enhancing watersheds and treaty resources within the ceded territory of the Nez Perce Tribe under the Treaty of 1855 with the United States Federal Government. The program uses a holistic approach, which encompasses entire watersheds, ridge top to ridge top, emphasizing all cultural aspects. We strive toward maximizing historic ecosystem productive health, for the restoration of anadromous and resident fish populations. The Nez Perce Tribal Fisheries/Watershed Program (NPTFWP) sponsors the Protect and Restore the Big Canyon Creek Watershed project. The NPTFWP has the authority to allocate funds under the provisions set forth in their contract with BPA. In the state of Idaho vast numbers of relatively small obstructions, such as road culverts, block thousands of miles of habitat suitable for a variety of fish species. To date, most agencies and land managers have not had sufficient, quantifiable data to adequately address these barrier sites. The ultimate objective of this comprehensive inventory and assessment was to identify all barrier crossings within the watershed. The barriers were then prioritized according to the

Anadromous fish behaviour important for fish passage

International Nuclear Information System (INIS)

Kynard, B.E.

1993-01-01

An understanding of the behavior of target fish species is necessary for proper design, location, and operation of a successful upstream or downstream fishway for anadromous migrants. Important fish behaviors are seasonal and daily timing of migration; rheotaxis and near field behavior; stimulus-response behavior; swimming capability; shoaling behavior; response to physical environmental factors such as illumination, sound, water depth, current velocity, and structure; response to chemicals; and response to biological factors such as competition for space and response to predators. The information on migrant fish behavior is reviewed, using examples from the literature on the behavior of eastern anadromous species, particularly Atlantic salmon (Salmo salar) and American shad (Alosa sapidissima). 87 refs

Design and implementation of a new autonomous sensor fish to support advanced hydropower development.

Science.gov (United States)

Deng, Z D; Lu, J; Myjak, M J; Martinez, J J; Tian, C; Morris, S J; Carlson, T J; Zhou, D; Hou, H

2014-11-01

Acceleration in development of additional conventional hydropower requires tools and methods to perform laboratory and in-field validation of turbine performance and fish passage claims. The new-generation Sensor Fish has been developed with more capabilities to accommodate a wider range of users over a broader range of turbine designs and operating environments. It provides in situ measurements of three-dimensional (3D) linear accelerations, 3D rotational velocities, 3D orientation, pressure, and temperature at a sampling frequency of 2048 Hz. It also has an automatic floatation system and built-in radio-frequency transmitter for recovery. The relative errors of the pressure, acceleration, and rotational velocity were within ±2%, ±5%, and ±5%, respectively. The accuracy of orientation was within ±4° and accuracy of temperature was ±2 °C. The new-generation Sensor Fish is becoming a major technology and being deployed for evaluating the conditions for fish passage of turbines or other hydraulic structures in both the United States and several other countries.

Passage of fish larvae and eggs through the Funil, Itutinga and Camargos Reservoirs on the upper Rio Grande (Minas Gerais, Brazil

Directory of Open Access Journals (Sweden)

Fábio Mineo Suzuki

Full Text Available The objective of this study was to evaluate the passage of fish eggs and larvae through the Funil, Itutinga and Camargos Reservoirs, located in the upper Rio Grande basin, Minas Gerais, Brazil. Samples were taken downstream and upstream of the dams using a conical ichthyoplankton net and were collected every two weeks, twice per sampling day, between November 2008 and March 2009. Although eggs and larvae were abundant immediately upstream of the reservoirs, no ichthyoplankton were captured immediately downstream of the dams, possibly indicating that eggs and larvae do not pass through the reservoirs. The arrival of ichthyoplankton in the reservoirs without its effective passage downstream makes the survival of these eggs and larvae unlikely. Furthermore, this lack of downstream movement may compromise the recruitment of species to downstream stretches, especially in the case of the Funil Reservoir (because of the presence of a fish pass in this dam. We emphasize that the fish lift operation at the Funil Dam must be carefully assessed, considering not only its efficiency but also its short- and long-term effects on the recruitment of migratory fish species from the river.

Umatilla River Fish Passage Operations Program, 2002-2003 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Bronson, James P. (Confederated Tribes of the Umatilla Indian Reservation, Department of Natural Resources, Pendleton, OR); Duke, Bill B. (Oregon Department of Fish and Wildlife, Pendleton, OR)

2004-03-01

Threemile Falls Dam (Threemile Dam), located near the town of Umatilla, is the major collection and counting point for adult salmonids returning to the Umatilla River. Returning salmon and steelhead were enumerated at Threemile Dam from August 17, 2002 to September 29, 2003. A total of 3,080 summer steelhead (Oncorhynchus mykiss); 1716 adult, 617 jack, and 1,709 subjack fall chinook (O. tshawytscha); 3,820 adult and 971 jack coho (O. kisutch); and 3,607 adult and 135 jack spring chinook (O. tshawytscha) were counted. All fish were enumerated at the east bank facility. Of the fish counted, 6 summer steelhead and 330 adult and 49 jack spring chinook were hauled upstream from Threemile Dam. There were 2,882 summer steelhead; 1161 adult, 509 jack and 1,546 subjack fall chinook; 3,704 adult and 915 jack coho; and 2,406 adult and 31 jack spring chinook either released at, or allowed to volitionally migrate past, Threemile Dam. Also, 109 summer steelhead; 532 adult and 32 jack fall chinook; and 560 adult and 28 jack spring chinook were collected for brood. In addition, 282 spring chinook were collected for the outplanting efforts in the Walla Walla Basin. The Westland Canal juvenile facility (Westland), located near the town of Echo at rivermile (RM) 27, is the major collection point for outmigrating juvenile salmonids and steelhead kelts. The canal was open for 159 days between January 27 and July 4, 2003. During that period, fish were bypassed back to the river 145 days and were trapped 11 days. An estimated 205 pounds of juvenile fish were transported from Westland to the Umatilla River boat ramp (RM 0.5). Approximately 82% of the juveniles transported were salmonids. No steelhead kelts were hauled from Westland this year. The Threemile Dam west bank juvenile bypass was opened on September 16, 2002. and continued until November 1, 2002. The bypass was reopened March 3, 2003 and ran until July 3, 2003. The juvenile trap was operated by the Umatilla Passage Evaluation

Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2004 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

DeHart, Michele (Columbia Basin Fish and Wildlife Authority, Portland, OR)

2005-07-01

The runoff volume for 2004 was below average throughout the Columbia Basin. At The Dalles the January-July runoff volume was 77% of average or 83.0 MAF. Grand Coulee, Hungry Horse, and Libby were below their Biological Opinion reservoir target elevations on April 10 at the beginning of the spring salmon migration season. All major storage reservoirs except Libby, Grand Coulee, Hungry Horse, Dworshak, and Brownlee were within a few feet of full by the end of June and early July. Overall, NOAA Biological Opinion seasonal flow targets were not met at any project for either spring or summer migrations of salmon and steelhead. Overall, spill was reduced in 2004. Implementation of Biological Opinion spill for fish passage measures was wrought with contention in 2004, particularly for summer spill which was finally the subject of litigation. The spring migration spill season began with debate among the fishery mangers and tribes and action agencies regarding spill at Bonneville Dam for the Spring Creek Hatchery release. The USFWS agreed to a spill test versus a corner collector operation to determine the best route for survival for these fish. The USFWS agreement includes no spill for early Spring Creek Hatchery releases for the next two years. Spring spill at Snake River transportation sites was eliminated after April 23, and transportation was maximized. The federal operators and regulators proposed to reduce Biological Opinion summer spill measures, while testing the impact of those reductions. This proposal was eventually rejected in challenges in the Federal Ninth Circuit Court. The Corps of Engineers reported that spill at Bonneville Dam in the 2002 to 2004 period was actually lower than reported due to a spill calibration error at the project. Because flows were low and spill levels were easily controlled few fish were observed with any signs of Gas Bubble Trauma. The annual Smolt Monitoring Program was implemented and provided in-season timing and passage

Hydroacoustic Evaluation of Juvenile Salmonid Passage at The Dalles Dam Spillway, 2006

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Khan, Fenton; Skalski, John R.; Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.

2007-05-24

The objective of this study was to determine detailed vertical, horizontal, intensive, and diel distributions of juvenile salmonid passage at the spillway at The Dalles Dam from April 12 to July16, 2006. These data are being applied in the Spillway Improvements Program to position release pipes for direct injury and mortality studies and to provide baseline data for assessment of the vortex suppression devices scheduled for deployment in 2007. We estimated fish distributions from hydroacoustic data collected with split-beam transducers arrayed across Bays 1 through 9 and 14. Spill at ~20 kcfs per bay was bulked at Bays 1-6, although the other bays were opened at times during the study to maintain a 40% spill percentage out of total project discharge. The vertical distribution of fish was skewed toward the surface during spring, but during summer, passage peaked at 2-3 m above the spillway ogee. Fish passage rates (number per hour) and fish densities (number per kcfs) were highest at Bay 6, followed by passage at Bay 5. This result comports with spillway horizontal distribution data from radio telemetry and hydroacoustic studies in 2004. The vertical and horizontal distribution of fish passage at bays 5 and 6 was much more variable during spring than summer and more variable at bay 5 than bay 6. Diel distribution data revealed that fish passage was highest during 0600-0700 h in spring; otherwise passage was reasonably uniform on a diel basis. This study substantiates the purpose of the spillway vortex suppression device to re-distribute downstream migrants away from Bay 6 toward Bays 1-5.

A barrier to upstream migration in the fish passage of Itaipu Dam (Canal da Piracema), Paraná River basin

Science.gov (United States)

,; Fontes Júnior, Hélio Martins; Makrakis, Sergio; Gomes, Luiz Carlos; Latini, João Dirço

2012-01-01

The majority of the fish passages built in the Neotropical region are characterised by low efficiency and high selectivity; in many cases, the benefits to fish populations are uncertain. Studies conducted in the Canal da Piracema at Itaipu dam on the Parana River indicate that the system component designated as the Discharge channel in the Bela Vista River (herein named Canal de deságue no rio Bela Vista or CABV), a 200 m long technical section, was the main barrier to the upstream migration. The aim of this study was to evaluate the degree of restriction imposed by the CABV on upstream movements of Prochilodus lineatus and Leporinus elongatus, Characiformes. Fish were tagged with passive integrated transponders (PIT tags) and released both downstream and upstream of this critical section. Individuals of both species released downstream of the CABV took much more time to reach the upper end of the system (43.6 days vs. 15.9 days), and passed in much lower proportions (18% vs. 60.8%) than those tagged upstream of this component. Although more work is needed to differentiate between fishway effects and natural variation in migratory motivation, the results clearly demonstrate passage problems at the CABV.

Improving fish survival through turbines

International Nuclear Information System (INIS)

Ferguson, J.W.

1993-01-01

Much of what is known about fish passage through hydroturbines has been developed by studying migratory species of fish passing through large Kaplan turbine units. A review of the literature on previous fish passage research presented in the accompanying story illustrates that studies have focused on determining mortality levels, rather than identifying the causal mechanism involved. There is a need for understanding how turbine designs could be altered to improve fish passage conditions, how to retrofit existing units, and how proposed hydro plant operational changes may affect fish survival. The US Army Corps of Engineers has developed a research program to define biologically based engineering criteria for improving fish passage conditions. Turbine designs incorporating these criteria can be evaluated for their effects on fish survival, engineering issues, costs, and power production. The research program has the following objectives: To gain a thorough knowledge of the mechanisms of fish mortality; To define the biological sensitivities of key fish species to these mechanisms of mortality; To develop new turbine design criteria to reduce fish mortality; To construct prototype turbine designs, and to test these designs for fish passage, hydro-mechanical operation, and power production; and To identify construction and power costs associated with new turbine designs

Development of computational fluid dynamics--habitat suitability (CFD-HSI) models to identify potential passage--Challenge zones for migratory fishes in the Penobscot River

Science.gov (United States)

Haro, Alexander J.; Dudley, Robert W.; Chelminski, Michael

2012-01-01

A two-dimensional computational fluid dynamics-habitat suitability (CFD–HSI) model was developed to identify potential zones of shallow depth and high water velocity that may present passage challenges for five anadromous fish species in the Penobscot River, Maine, upstream from two existing dams and as a result of the proposed future removal of the dams. Potential depth-challenge zones were predicted for larger species at the lowest flow modeled in the dam-removal scenario. Increasing flows under both scenarios increased the number and size of potential velocity-challenge zones, especially for smaller species. This application of the two-dimensional CFD–HSI model demonstrated its capabilities to estimate the potential effects of flow and hydraulic alteration on the passage of migratory fish.

Fish passage through hydropower turbines: Simulating blade strike using the discrete element method

International Nuclear Information System (INIS)

Richmond, M C; Romero-Gomez, P

2014-01-01

Among the hazardous hydraulic conditions affecting anadromous and resident fish during their passage though hydro-turbines two common physical processes can lead to injury and mortality: collisions/blade-strike and rapid decompression. Several methods are currently available to evaluate these stressors in installed turbines, e.g. using live fish or autonomous sensor devices, and in reduced-scale physical models, e.g. registering collisions from plastic beads. However, a priori estimates with computational modeling approaches applied early in the process of turbine design can facilitate the development of fish-friendly turbines. In the present study, we evaluated the frequency of blade strike and rapid pressure change by modeling potential fish trajectories with the Discrete Element Method (DEM) applied to fish-like composite particles. In the DEM approach, particles are subjected to realistic hydraulic conditions simulated with computational fluid dynamics (CFD), and particle-structure interactions-representing fish collisions with turbine components such as blades-are explicitly recorded and accounted for in the calculation of particle trajectories. We conducted transient CFD simulations by setting the runner in motion and allowing for unsteady turbulence using detached eddy simulation (DES), as compared to the conventional practice of simulating the system in steady state (which was also done here for comparison). While both schemes yielded comparable bulk hydraulic performance values, transient conditions exhibited an improvement in describing flow temporal and spatial variability. We released streamtraces (in the steady flow solution) and DEM particles (transient solution) at the same locations where sensor fish (SF) were released in previous field studies of the advanced turbine unit. The streamtrace- based results showed a better agreement with SF data than the DEM-based nadir pressures did because the former accounted for the turbulent dispersion at the

Restoring stream habitat connectivity: a proposed method for prioritizing the removal of resident fish passage barriers.

Science.gov (United States)

O'Hanley, Jesse R; Wright, Jed; Diebel, Matthew; Fedora, Mark A; Soucy, Charles L

2013-08-15

Systematic methods for prioritizing the repair and removal of fish passage barriers, while growing of late, have hitherto focused almost exclusively on meeting the needs of migratory fish species (e.g., anadromous salmonids). An important but as of yet unaddressed issue is the development of new modeling approaches which are applicable to resident fish species habitat restoration programs. In this paper, we develop a budget constrained optimization model for deciding which barriers to repair or remove in order to maximize habitat availability for stream resident fish. Habitat availability at the local stream reach is determined based on the recently proposed C metric, which accounts for the amount, quality, distance and level of connectivity to different stream habitat types. We assess the computational performance of our model using geospatial barrier and stream data collected from the Pine-Popple Watershed, located in northeast Wisconsin (USA). The optimization model is found to be an efficient and practical decision support tool. Optimal solutions, which are useful in informing basin-wide restoration planning efforts, can be generated on average in only a few minutes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Migration depth and residence time of juvenile salmonids in the forebays of hydropower dams prior to passage through turbines or juvenile bypass systems: implications for turbine-passage survival.

Science.gov (United States)

Li, Xinya; Deng, Zhiqun D; Brown, Richard S; Fu, Tao; Martinez, Jayson J; McMichael, Geoffrey A; Skalski, John R; Townsend, Richard L; Trumbo, Bradly A; Ahmann, Martin L; Renholds, Jon F

2015-01-01

Little is known about the three-dimensional depth distributions in rivers of individually marked fish that are in close proximity to hydropower facilities. Knowledge of the depth distributions of fish approaching dams can be used to understand how vulnerable fish are to injuries such as barotrauma as they pass through dams. To predict the possibility of barotrauma injury caused by pressure changes during turbine passage, it is necessary to understand fish behaviour relative to acclimation depth in dam forebays as they approach turbines. A guiding study was conducted using high-resolution three-dimensional tracking results of salmonids implanted with Juvenile Salmon Acoustic Telemetry System transmitters to investigate the depth distributions of subyearling and yearling Chinook salmon (Oncorhynchus tshawytscha) and juvenile steelhead (Oncorhynchus mykiss) passing two dams on the Snake River in Washington State. Multiple approaches were evaluated to describe the depth at which fish were acclimated, and statistical analyses were performed on large data sets extracted from ∼28 000 individually tagged fish during 2012 and 2013. Our study identified patterns of depth distributions of juvenile salmonids in forebays prior to passage through turbines or juvenile bypass systems. This research indicates that the median depth at which juvenile salmonids approached turbines ranged from 2.8 to 12.2 m, with the depths varying by species/life history, year, location (which dam) and diel period (between day and night). One of the most enlightening findings was the difference in dam passage associated with the diel period. The amount of time that turbine-passed fish spent in the immediate forebay prior to entering the powerhouse was much lower during the night than during the day. This research will allow scientists to understand turbine-passage survival better and enable them to assess more accurately the effects of dam passage on juvenile salmon survival.

Enloe Dam Passage Project, Volume I, 1984 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Fanning, M.L.

1985-07-01

This report discusses issues related to the provision of fish passage facilities at Enloe Dam and the introduction of anadromous salmonid fish to the upper Similkameen River basin. The species of fish being considered is a summer run of steelhead trout adapted to the upper Columbia basin. (ACR)

Evaluation of swimming capability and potential velocity barrier problems for fish. Part A: Swimming performance of selected warm and cold water fish species relative to fish passage and fishway design

International Nuclear Information System (INIS)

Scruton, D. A.; Goosney, R. G.; McKinley, R. S.; Booth, R. K.; Peake, S.

1998-08-01

The objective of this study was to provide information about the swimming capability of several widely distributed, economically or recreationally important fish species, for use in mitigating potential velocity barrier problems associated with hydroelectric power facilities. Swimming capability of anadromous and landlocked Atlantic salmon, brook trout, brown trout, lake sturgeon, and walleye, collected from various locations throughout Canada, were investigated to develop criteria for sustained, prolonged, burst swimming performance characteristics of the study species, fish physiology, life history and migration distance on swimming performance. Swimming performance characteristics in the wild, especially the use of physiological telemetry, as well as development of new methodology for the measurement of burst speed was also central to the study. Models were derived to describe swimming capabilities for each study species/life stage in relation to fish length, water velocity, water temperature, and other significant environmental factors. The data will form the basis of guideline development and decision making to improve design and evaluation of fish passage facilities. A series of annotated bibliographies resulting from the study are described in Appendix B. 74 refs., 8 tabs., figs., 2 appendices

Identifying and Evaluating Options for Improving Sediment Management and Fish Passage at Hydropower Dams in the Lower Mekong River Basin

Science.gov (United States)

Wild, T. B.; Reed, P. M.; Loucks, D. P.

2015-12-01

The Mekong River basin in Southeast Asia is undergoing intensive and pervasive hydropower development to satisfy demand for increased energy and income to support its growing population of 60 million people. Just 20 years ago this river flowed freely. Today some 30 large dams exist in the basin, and over 100 more are being planned for construction. These dams will alter the river's natural water, sediment and nutrient flows, thereby impacting river morphology and ecosystems, and will fragment fish migration pathways. In doing so, they will degrade one of the world's most valuable and productive freshwater fish habitats. For those dams that have not yet been constructed, there still exist opportunities to modify their siting, design and operation (SDO) to potentially achieve a more balanced set of tradeoffs among hydropower production, sediment/nutrient passage and fish passage. We introduce examples of such alternative SDO opportunities for Sambor Dam in Cambodia, planned to be constructed on the main stem of the Mekong River. To evaluate the performance of such alternatives, we developed a Python-based simulation tool called PySedSim. PySedSim is a daily time step mass balance model that identifies the relative tradeoffs among hydropower production, and flow and sediment regime alteration, associated with reservoir sediment management techniques such as flushing, sluicing, bypassing, density current venting and dredging. To date, there has been a very limited acknowledgement or evaluation of the significant uncertainties that impact the evaluation of SDO alternatives. This research is formalizing a model diagnostic assessment of the key assumptions and parametric uncertainties that strongly influence PySedSim SDO evaluations. Using stochastic hydrology and sediment load data, our diagnostic assessment evaluates and compares several Sambor Dam alternatives using several performance measures related to energy production, sediment trapping and regime alteration, and

Behavior and dam passage of juvenile Chinook salmon at Cougar Reservoir and Dam, Oregon, March 2011 - February 2012

Science.gov (United States)

Beeman, John W.; Hansel, Hal C.; Hansen, Amy C.; Haner, Philip V.; Sprando, Jamie M.; Smith, Collin D.; Evans, Scott D.; Hatton, Tyson W.

2013-01-01

The movements and dam passage of juvenile Chinook salmon implanted with acoustic transmitters and passive integrated transponder tags were studied at Cougar Reservoir and Dam, near Springfield, Oregon. The purpose of the study was to provide information to aid with decisions about potential alternatives for improving downstream passage conditions for juvenile salmonids in this flood-control reservoir. In 2011, a total of 411 hatchery fish and 26 wild fish were tagged and released during a 3-month period in the spring, and another 356 hatchery fish and 117 wild fish were released during a 3-month period in the fall. A series of 16 autonomous hydrophones throughout the reservoir and 12 hydrophones in a collective system near the dam outlet were used to determine general movements and dam passage of the fish over the life of the acoustic transmitter, which was expected to be about 3 months. Movements within the reservoir were directional, and it was common for fish to migrate repeatedly from the head of the reservoir downstream to the dam outlet and back to the head of the reservoir. Most fish were detected near the temperature control tower at least once. The median time from release near the head of the reservoir to detection within about 100 meters of the dam outlet at the temperature control tower was between 5.7 and 10.8 days, depending on season and fish origin. Dam passage events occurred over a wider range of dates in the spring and summer than in the fall and winter, but dam passage numbers were greatest during the fall and winter. A total of 10.5 percent (43 of 411) of the hatchery fish and 15.4 percent (4 of 26) of the wild fish released in the spring are assumed to have passed the dam, whereas a total of 25.3 percent (90 of 356) of the hatchery fish and 16.9 percent (30 of 117) of the wild fish released in the fall are assumed to have passed the dam. A small number of fish passed the dam after their transmitters had stopped working and were detected at

Evaluation of Application Space Expansion for the Sensor Fish

Energy Technology Data Exchange (ETDEWEB)

DeRolph, Christopher R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevelhimer, Mark S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-02-01

The Pacific Northwest National Laboratory has developed an instrument known as the sensor fish that can be released into downstream passage routes at hydropower facilities to collect data on the physical conditions that a fish might be exposed to during passage through a turbine. The US Department of Energy Wind and Water Power Program sees value in expanding the sensor fish application space beyond large Kaplan turbines in the northwest United States to evaluate conditions to which a greater variety of fish species are exposed. Development of fish-friendly turbines requires an understanding of both physical passage conditions and biological responses to those conditions. Expanding the use of sensor fish into other application spaces will add to the knowledge base of physical passage conditions and could also enhance the use of sensor fish as a site-specific tool in mitigating potential impacts to fish populations from hydropower. The Oak Ridge National Laboratory (ORNL) National Hydropower Assessment Program (NHAAP) database contains hydropower facility characteristics that, along with national fish distribution data, were used to evaluate potential interactions between fish species and project characteristics related to downstream passage issues. ORNL developed rankings for the turbine types in the NHAAP database in terms of their potential to impact fish through injury or mortality during downstream turbine passage. National-scale fish distributions for 31 key migratory species were spatially intersected with hydropower plant locations to identify facilities where turbines with a high threat to fish injury or mortality overlap with the potential range of a sensitive fish species. A dataset was produced that identifies hydropower facilities where deployment of the sensor fish technology might be beneficial in addressing issues related to downstream fish passage. The dataset can be queried to target specific geographic regions, fish species, license expiration

Is motivation important to brook trout passage through culverts?

Science.gov (United States)

Goerig, Elsa; Castro-Santos, Theodore R.

2017-01-01

Culverts can restrict movement of stream-dwelling fish. Motivation to enter and ascend these structures is an essential precursor for successful passage. However, motivation is challenging to quantify. Here, we use attempt rate to assess motivation of 447 brook trout (Salvelinus fontinalis) entering three culverts under a range of hydraulic, environmental, and biological conditions. A passive integrated transponder system allowed for the identification of passage attempts and success of individual fish. Attempt rate was quantified using time-to-event analysis allowing for time-varying covariates and recurrent events. Attempt rate was greatest during the spawning period, at elevated discharge, at dusk, and for longer fish. It decreased during the day and with increasing number of conspecifics downstream of the culvert. Results also show a positive correlation between elevated motivation and successful passage. This study enhances understanding of factors influencing brook trout motivation to ascend culverts and shows that attempt rate is a dynamic phenomenon, variable over time and among individuals. It also presents methods that could be used to investigate other species’ motivation to pass natural or anthropogenic barriers.

Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2011

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Batten, G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cushing, Aaron W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Jin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Gary E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skalski, J. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Townsend, Richard L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Seaburg, Adam [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodley, Christa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hughes, James S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carpenter, Scott M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Deng, Zhiqun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Etherington, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fischer, Eric S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fu, Tao [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Greiner, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hennen, Matthew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Martinez, Jayson J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mitchell, T. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rayamajhi, Bishes [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zimmerman, Shon A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2013-02-15

Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2011. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a virtual/paired-release model. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon using a virtual release, paired reference release survival model. This study supports the U.S. Army Corps of Engineers’ continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Proceedings of a workshop on American Eel passage technologies

Science.gov (United States)

Haro, Alexander J.

2013-01-01

Recent concerns regarding a decline in recruitment of American eels (Anguilla rostrata) have prompted efforts to restore this species to historic habitats by providing passage for both upstream migrant juveniles and downstream migrant adults at riverine barriers, including low-head and hydroelectric dams (Castonguay et al. 1994, Haro et al. 2000). These efforts include development of management plans and stock assessment reviews in both the US and Canada (COSEWIC 2006, Canadian Eel Working Group 2009, DFO 2010, MacGregor et al. 2010, ASMFC 2000, ASMFC 2006, ASMFC 2008, Williams and Threader 2007), which target improvement of upstream and downstream passage for eels, as well as identification and prioritization of research needs for development of new and more effective passage technologies for American eels. Traditional upstream fish passage structures, such as fishways and fish lifts, are often ineffective passing juvenile eels, and specialized passage structures for this species are needed. Although designs for such passage structures are available and diverse (Knights and White 1998, Porcher 2002, FAO/DVWK 2002, Solomon and Beach 2004a,b, Environment Agency UK 2011), many biologists, managers, and engineers are unfamiliar with eel pass design and operation, or unaware of the technical options available for upstream eel passage, Better coordination is needed to account for eel passage requirements during restoration efforts for other diadromous fish species. Also, appropriately siting eel passes at hydropower projects is critical, and siting can be difficult and complex due to physical restrictions in access to points of natural concentrations of eels, dynamic hydraulics of tailrace areas, and presence of significant competing flows from turbine outfalls or spill. As a result, some constructed eel passes are sited poorly and may pass only a fraction of the number of eels attempting to pass the barrier. When sited and constructed appropriately, however, eel passes

Turbine related fish mortality

International Nuclear Information System (INIS)

Eicher, G.J.

1993-01-01

A literature review was conducted to assess the factors affecting turbine-related fish mortality. The mechanics of fish passage through a turbine is outlined, and various turbine related stresses are described, including pressure and shear effects, hydraulic head, turbine efficiency, and tailwater level. The methodologies used in determining the effects of fish passage are evaluated. The necessity of adequate controls in each test is noted. It is concluded that mortality is the result of several factors such as hardiness of study fish, fish size, concentrations of dissolved gases, and amounts of cavitation. Comparisons between Francis and Kaplan turbines indicate little difference in percent mortality. 27 refs., 5 figs

Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Kim, Jin A.; Royer, Ida M.; Batten, George W.; Cushing, Aaron W.; Carpenter, Scott M.; Etherington, D. J.; Faber, Derrek M.; Fischer, Eric S.; Fu, Tao; Hennen, Matthew J.; Mitchell, Tyler; Monter, Tyrell J.; Skalski, John R.; Townsend, Richard L.; Zimmerman, Shon A.

2011-12-01

Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing Through Bonneville Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Kim, Jin A.; Royer, Ida M.; Batten, George W.; Cushing, Aaron W.; Carpenter, Scott M.; Etherington, D. J.; Faber, Derrek M.; Fischer, Eric S.; Fu, Tao; Hennen, Matthew J.; Mitchell, T. D.; Monter, Tyrell J.; Skalski, J. R.; Townsend, Richard L.; Zimmerman, Shon A.

2012-09-01

Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Compliance Monitoring of Subyearling Chinook Salmon Survival and Passage at The Dalles Dam, Summer 2012

Energy Technology Data Exchange (ETDEWEB)

Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Johnson, Gary E.

2013-05-01

The purpose of this compliance study was to estimate dam passage survival of subyearling Chinook salmon at The Dalles Dam during summer 2012. Under the 2008 Federal Columbia River Power System Biological Opinion, dam passage survival is required to be greater than or equal to 0.93 and estimated with a standard error (SE) less than or equal to 0.015. The study also estimated survival from the forebay 2 km upstream of the dam and through the tailrace to 2 km downstream of the dam, forebay residence time, tailrace egress time, spill passage efficiency (SPE), and fish passage efficiency (FPE), as required by the 2008 Columbia Basin Fish Accords.

Compliance Monitoring of Yearling Chinook Salmon and Juvenile Steelhead Survival and Passage at Bonneville Dam, Spring 2011

Energy Technology Data Exchange (ETDEWEB)

Skalski, John R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Carlson, Thomas J.

2012-06-07

The study was designed to estimate dam passage survival at Bonneville Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and to provide additional fish passage performance measures at that site as stipulated in the Columbia Basin Fish Accords.

Compliance Monitoring of Yearling Chinook Salmon and Juvenile Steelhead Survival and Passage at Bonneville Dam, Spring 2011

Energy Technology Data Exchange (ETDEWEB)

Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Carlson, Thomas J.

2012-03-01

The study was designed to estimate dam passage survival at Bonneville Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and to provide additional fish passage performance measures at that site as stipulated in the Columbia Basin Fish Accords.

Mussel Spat Ropes Assist Redfin Bully Gobiomorphus huttoni Passage through Experimental Culverts with Velocity Barriers

Directory of Open Access Journals (Sweden)

Jonathan D. Tonkin

2012-09-01

Full Text Available The application of mussel spat rope for enabling the passage of redfin bully Gobiomorphus huttoni through culverts, which create velocity barriers, was trialled in the laboratory. No fish were able to access the un-roped control pipes whereas 52% successfully negotiated the pipes in the rope treatments. The success of fish ascending treatment pipes suggests mussel spat rope may be effective for enabling the passage of this and other similar fish species through otherwise impassable culverts with velocity barriers.

A multi-year analysis of passage and survival at McNary Dam, 2004-09

Science.gov (United States)

Adams, Noah S.; Walker, C.E.; Perry, R.W.

2011-01-01

We analyzed 6 years (2004–09) of passage and survival data collected at McNary Dam to determine how dam operations and environmental conditions affect passage and survival of juvenile salmonids. A multinomial logistic regression was used to examine how environmental variables and dam operations relate to passage behavior of juvenile salmonids at McNary Dam. We used the Cormack-Jolly-Seber release-recapture model to determine how the survival of juvenile salmonids passing through McNary Dam relates to environmental variables and dam operations. Total project discharge and the proportion of flow passing the spillway typically had a positive effect on survival for all species and routes. As the proportion of water through the spillway increased, the number of fish passing the spillway increased, as did overall survival. Additionally, survival generally was higher at night. There was no meaningful difference in survival for fish that passed through the north or south portions of the spillway or powerhouse. Similarly, there was no difference in survival for fish released in the north, middle, or south portions of the tailrace. For subyearling Chinook salmon migrating during the summer season, increased temperatures had a drastic effect on passage and survival. As temperature increased, survival of subyearling Chinook salmon decreased through all passage routes and the number of fish that passed through the turbines increased. During years when the temporary spillway weirs (TSWs) were installed, passage through the spillway increased for spring migrants. However, due to the changes made in the location of the TSW between years and the potential effect of other confounding environmental conditions, it is not certain if the increase in spillway passage was due solely to the presence of the TSWs. The TSWs appeared to improve forebay survival during years when they were operated.

Effect of electric barrier on passage and physical condition of juvenile and adult rainbow trout

Science.gov (United States)

Layhee, Megan J.; Sepulveda, Adam; Shaw, Amy; Smuckall, Matthew; Kapperman, Kevin; Reyes, Alejandro

2016-01-01

Electric barriers can inhibit passage and injure fish. Few data exist on electric barrier parameters that minimize these impacts and on how body size affects susceptibility, especially to nontarget fish species. The goal of this study was to determine electric barrier voltage and pulse-width settings that inhibit passage of larger bodied rainbow trout Oncorhynchus mykiss (215–410 mm fork length) while allowing passage of smaller bodied juvenile rainbow trout (52–126 mm) in a static laboratory setting. We exposed rainbow trout to 30-Hz pulsed-direct current voltage gradients (0.00–0.45 V cm−1) and pulse widths (0.0–0.7 ms) and recorded their movement, injury incidence, and mortality. No settings tested allowed all juveniles to pass while impeding all adult passage. Juvenile and adult rainbow trout avoided the barrier at higher pulse widths, and fewer rainbow trout passed the barrier at 0.7-ms pulse width compared to 0.1 ms and when the barrier was turned off. We found no effect of voltage gradient on fish passage. No mortality occurred, and we observed external bruising in 5 (7%) juvenile rainbow trout and 15 (21%) adult rainbow trout. This study may aid managers in selecting barrier settings that allow for increased juvenile passage.

Access to Workplace Accommodations to Support Breastfeeding after Passage of the Affordable Care Act.

Science.gov (United States)

Kozhimannil, Katy B; Jou, Judy; Gjerdingen, Dwenda K; McGovern, Patricia M

2016-01-01

This study examines access to workplace accommodations for breastfeeding, as mandated by the Affordable Care Act, and its associations with breastfeeding initiation and duration. We hypothesize that women with access to reasonable break time and private space to express breast milk would be more likely to breastfeed exclusively at 6 months and to continue breastfeeding for a longer duration. Data are from Listening to Mothers III, a national survey of women ages 18 to 45 who gave birth in 2011 and 2012. The study population included women who were employed full or part time at the time of survey. Using two-way tabulation, logistic regression, and survival analysis, we characterized women with access to breastfeeding accommodations and assessed the associations between these accommodations and breastfeeding outcomes. Only 40% of women had access to both break time and private space. Women with both adequate break time and private space were 2.3 times (95% CI, 1.03-4.95) as likely to be breastfeeding exclusively at 6 months and 1.5 times (95% CI, 1.08-2.06) as likely to continue breastfeeding exclusively with each passing month compared with women without access to these accommodations. Employed women face unique barriers to breastfeeding and have lower rates of breastfeeding initiation and shorter durations, despite compelling evidence of associated health benefits. Expanded access to workplace accommodations for breastfeeding will likely entail collaborative efforts between public health agencies, employers, insurers, and clinicians to ensure effective workplace policies and improved breastfeeding outcomes. Copyright © 2016 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Technologies for evaluating fish passage through turbines

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2003-10-01

This study evaluated the feasibility of two types of technologies to observe fish and near neutrally buoyant drogues as they move through hydropower turbines. Existing or reasonably modified light-emitting and ultrasonic technologies were used to observe flow patterns, the response of fish to flow, and interactions between fish and turbine structures with good spatial and temporal accuracy. This information can be used to assess the biological benefits of turbine design features such as reductions in gaps at the tips and hub of turbine runner blades, reshaping wicket gates and stay vanes, modifications to draft tube splitter piers, and design changes that enhance egress through the powerhouse and tailrace.

Water intake fish diversion apparatus

International Nuclear Information System (INIS)

Taft, E.P. III; Cook, T.C.

1995-01-01

A fish diversion apparatus uses a plane screen to divert fish for variety of types of water intakes in order to protect fish from injury and death. The apparatus permits selection of a relatively small screen angle, for example ten degrees, to minimize fish injury. The apparatus permits selection of a high water velocity, for example ten feet per second, to maximize power generation efficiency. The apparatus is especially suitable retrofit to existing water intakes. The apparatus is modular to allow use plural modules in parallel to adjust for water flow conditions. The apparatus has a floor, two opposite side walls, and a roof which define a water flow passage and a plane screen within the passage. The screen is oriented to divert fish into a fish bypass which carries fish to a safe discharge location. The dimensions of the floor, walls, and roof are selected to define the dimensions of the passage and to permit selection of the screen angle. The floor is bi-level with a level upstream of the screen and a level beneath screen selected to provide a uniform flow distribution through the screen. The apparatus may include separation walls to provide a water flow channel between the apparatus and the water intake. Lead walls may be used to adjust water flow conditions into the apparatus. The apparatus features stoplog guides near its upstream and downstream ends to permit the water flow passage to be dewatered. 3 figs

Monitoring of Subyearling Chinook Salmon Survival and Passage at Bonneville Dam, Summer 2010

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Weiland, Mark A.; Carlson, Thomas J.

2012-09-01

The purpose of this study was to estimate dam passage and route specific survival rates for subyearling Chinook salmon smolts to a primary survival-detection array located 81 km downstream of the dam, evaluate a BGS located in the B2 forebay, and evaluate effects of two spill treatments. The 2010 study also provided estimates of forebay residence time, tailrace egress time, spill passage efficiency (SPE), and spill + B2 Corner Collector (B2CC) efficiency, as required in the Columbia Basin Fish Accords. In addition, the study estimated forebay passage survival and survival of fish traveling from the forebay entrance array, through the dam and downstream through 81 km of tailwater.

Compliance Monitoring of Yearling Chinook Salmon and Juvenile Steelhead Survival and Passage at John Day Dam, Spring 2011

Energy Technology Data Exchange (ETDEWEB)

Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Weiland, Mark A.; Woodley, Christa M.; Hughes, James S.; Carlson, Thomas J.

2012-06-01

The study was designed to estimate dam passage survival at John Day Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and to provide additional fish passage performance measures at that site as stipulated in the Columbia Basin Fish Accords.

Compliance Monitoring of Yearling Chinook Salmon and Juvenile Steelhead Survival and Passage at John Day Dam, Spring 2011

Energy Technology Data Exchange (ETDEWEB)

Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Weiland, Mark A.; Woodley, Christa M.; Hughes, James S.; Carlson, Thomas J.

2012-02-01

The study was designed to estimate dam passage survival at John Day Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and to provide additional fish passage performance measures at that site as stipulated in the Columbia Basin Fish Accords.

Survival and Passage of Yearling and Subyearling Chinook Salmon and Juvenile Steelhead at McNary Dam, 2012

Energy Technology Data Exchange (ETDEWEB)

Hughes, James S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodley, Christa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ploskey, Gene R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carpenter, Scott M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hennen, Matthew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fischer, Eric S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Batton, George [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cushing, Aaron W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Deng, Zhiqun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Etherington, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fu, Tao [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Greiner, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ingraham, John M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Jin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Li, Xi [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Martinez, Jayson J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mitchell, T. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rayamajhi, Bishes [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Seaburg, Adam [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skalski, J. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Townsend, Richard L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wagner, Katie A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zimmerman, Shon A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2013-12-23

The study was designed to evaluate the passage and survival of yearling and subyearling Chinook salmon and juvenile steelhead at McNary Dam as stipulated by the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a virtual/paired-release model. This study supports the USACE’s continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Hydroacoustic Evaluation of Juvenile Salmonid Passage at The Dalles Dam Sluiceway, 2005

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Khan, Fenton; Hedgepeth, J; Mueller, Robert P.; Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.; Skalski, John R.

2006-06-01

The U.S. Army Corps of Engineers Portland District engaged the Pacific Northwest National Laboratory to evaluate fish passage at The Dalles Dam powerhouse in 2005. The goal of the study was to provide information on smolt passage that will inform decisions on long-term measures and operations to enhance sluiceway passage and reduce turbine passage to improve smolt survival at the dam. The study addressed one of the main programs dedicated to improving juvenile salmonid survival at The Dalles Dam: Surface Flow Bypass. The study objectives (see below) were met using a combination of hydroacoustic and hydraulic data. The study incorporated fixed-location hydroacoustic methods across the entire powerhouse, with especially intense sampling using multiple split-beam transducers at all sluiceway portals. We did not sample fish passage at the spillway in 2005. In the sluiceway nearfield, we used an acoustic camera to track fish movements. The fish data were interpreted with hydraulic data from a computational fluid dynamics (CFD) model. Fish passage data were collected in the framework of an “experiment” using a randomized block design (3-day treatments; two treatments) to compare two sluiceway operational configurations: Sluice 2+5 and Sluice 2+19 (six gates open for each configuration). Total project outflow was 76% of the 10-year average for spring and 71% of the 10-year average for summer. Based on these findings, we make the following recommendations: 1) The sluice should be operated 24 h/d from April until November. 2) Open six rather than three sluice gates to take advantage of the maximum hydraulic capacity of the sluiceway. 3) Open the three gates above the western-most operating main turbine unit and the three gates at MU 8 where turbine passage rates are relatively high. 4) Operate the turbine units below open sluice gates as a standard fish operations procedure. 5) Develop hydraulic and entrance enhancements to the sluiceway to tap the potential of The

Mussel Spat Ropes Assist Redfin Bully Gobiomorphus huttoni Passage through Experimental Culverts with Velocity Barriers

Directory of Open Access Journals (Sweden)

Liam A.H. Wright

2012-09-01

Full Text Available The application of mussel spat rope for enabling the passage of redfin bully Gobiomorphus huttoni through culverts, which create velocity barriers, was trialled in the laboratory. No fish were able to access the un-roped control pipes whereas 52% successfully negotiated the pipes in the rope treatments. The success of fish ascending treatment pipes suggests mussel spat rope may be effective for enabling the passage of this and other similar fish species through otherwise impassable culverts with velocity barriers.

Migration depth and residence time of juvenile salmonids in the forebays of hydropower dams prior to passage through turbines or juvenile bypass systems: implications for turbine-passage survival

OpenAIRE

Li, Xinya; Deng, Zhiqun D.; Brown, Richard S.; Fu, Tao; Martinez, Jayson J.; McMichael, Geoffrey A.; Skalski, John R.; Townsend, Richard L.; Trumbo, Bradly A.; Ahmann, Martin L.; Renholds, Jon F.

2015-01-01

Little is known about the three-dimensional depth distributions in rivers of individually marked fish that are in close proximity to hydropower facilities. Knowledge of the depth distributions of fish approaching dams can be used to understand how vulnerable fish are to injuries such as barotrauma as they pass through dams. To predict the possibility of barotrauma injury caused by pressure changes during turbine passage, it is necessary to understand fish behaviour relative to acclimation dep...

Acoustic Telemetry Evaluation of Juvenile Salmonid Passage and Survival at John Day Dam, 2011

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A.; Woodley, Christa M.; Ploskey, Gene R.; Hughes, James S.; Hennen, Matthew J.; Kim, Jin A.; Deng, Zhiqun; Fu, Tao; Skalski, J. R.; Townsend, Richard L.; Wagner, Katie A.; Fischer, Eric S.; Duncan, Joanne P.; Batten, G.; Carlson, Thomas J.; Carpenter, Scott M.; Cushing, Aaron W.; Elder, T.; Etherington, D. J.; Johnson, Gary E.; Khan, Fenton; Miracle, Ann L.; Mitchell, T. D.; Prather, K.; Rayamajhi, Bishes; Royer, Ida; Seaburg, Adam; Zimmerman, Shon A.

2013-06-21

This report presents survival, behavioral, and fish passage results for tagged yearling Chinook salmon and juvenile steelhead as part of a survival study conducted at John Day Dam during spring 2011. This study was designed to evaluate the passage and survival of yearling Chinook salmon and juvenile steelhead to assist managers in identifying dam operations for compliance testing as stipulated by the 2008 Federal Columbia River Power System Biological Opinion and the 2008 Columbia Basin Fish Accords. Survival estimates were based on a paired-release survival model.

Using computational fluid dynamics to address fish passage concerns at the Grand Falls-Windsor hydroelectric development

International Nuclear Information System (INIS)

Woolgar, R.; Eddy, W.

2006-01-01

As a result of replacing the penstocks used to divert water to the generating station with a power canal, the study of out-migration survival of Atlantic salmon at Abitibi-Consolidated Company of Canada's (Abitibi) Grand Falls-Windsor Hydroelectric Development began in 1997. Using a behavioral louvre system, a fish bypass diversion system was implemented within the power canal. When the power canal first commenced operation in 1997 and after a new 30 MW Unit was installed in 2003, the efficiency of the system to divert the migrating smolt was low. In order to test improvements to the system, physical modeling was conducted at the University of Waterloo between 1997 and 2002. This led to increased efficiencies of fish passage before the new unit was installed. However, recent results of the physical modeling, including the new unit, did not detail the extent of changes required to the system to increase fish bypass efficiency. Abitibi then engaged SGE Acres Limited in the winter of 2004 to investigate alternatives for increasing the effectiveness of the Grand Falls Power Canal Fish Bypass Diversion System. Abitibi then re-engaged SGE Acres in July 2005 for follow-up work after the collection of physical data in the power canal by Environment Canada in June 2005. This paper presented documentation on the original analysis conducted in 2004 and 2005, and the follow-up work conducted in 2005 and 2006. Specifically, the paper discussed the development of a computational fluid dynamics model (FLOW-3D) to represent the existing condition of the power canal; simulations of the existing condition for various flows; review of model results to confirm if the model is representing overall canal hydraulics; simulation of various alternatives to increase fish bypass efficiency; and, selection of a preferred alternative. As part of the follow-up work, the paper presented a review of Environment Canada measurements and comparison with FLOW-3D model results, and additional

Passage and survival probabilities of juvenile Chinook salmon at Cougar Dam, Oregon, 2012

Science.gov (United States)

Beeman, John W.; Evans, Scott D.; Haner, Philip V.; Hansel, Hal C.; Hansen, Amy C.; Smith, Collin D.; Sprando, Jamie M.

2014-01-01

This report describes studies of juvenile-salmon dam passage and apparent survival at Cougar Dam, Oregon, during two operating conditions in 2012. Cougar Dam is a 158-meter tall rock-fill dam used primarily for flood control, and passes water through a temperature control tower to either a powerhouse penstock or to a regulating outlet (RO). The temperature control tower has moveable weir gates to enable water of different elevations and temperatures to be drawn through the dam to control water temperatures downstream. A series of studies of downstream dam passage of juvenile salmonids were begun after the National Oceanic and Atmospheric Administration determined that Cougar Dam was impacting the viability of anadromous fish stocks. The primary objectives of the studies described in this report were to estimate the route-specific fish passage probabilities at the dam and to estimate the survival probabilities of fish passing through the RO. The first set of dam operating conditions, studied in November, consisted of (1) a mean reservoir elevation of 1,589 feet, (2) water entering the temperature control tower through the weir gates, (3) most water routed through the turbines during the day and through the RO during the night, and (4) mean RO gate openings of 1.2 feet during the day and 3.2 feet during the night. The second set of dam operating conditions, studied in December, consisted of (1) a mean reservoir elevation of 1,507 ft, (2) water entering the temperature control tower through the RO bypass, (3) all water passing through the RO, and (4) mean RO gate openings of 7.3 feet during the day and 7.5 feet during the night. The studies were based on juvenile Chinook salmon (Oncorhynchus tshawytscha) surgically implanted with radio transmitters and passive integrated transponder (PIT) tags. Inferences about general dam passage percentage and timing of volitional migrants were based on surface-acclimated fish released in the reservoir. Dam passage and apparent

Fish injury and mortality during passage through pumping stations

NARCIS (Netherlands)

Esch, van B.P.M.

2012-01-01

An unwanted side effect of pumping stations is that fish suffer from injury and mortality when passing through the pumps and that fish migration is hampered. In recent years, the development of so-called fish-friendly pumping stations has received increasing attention from European governmental

Upstream Atlantic salmon (Salmo salar) passage

International Nuclear Information System (INIS)

Clay, C.H.

1993-01-01

Upstream salmon passage though a dam is discussed with respect to three main components: the fishway entrance, the fishway, and the exit. Design considerations and alternative types of components are presented. For fishway entrances, an important consideration is the positioning of the entrance as far upstream as the fish can swim with respect to obstacles. For powerhouses using water diverted from a river, the problem of leading fish past the powerhouse may be overcome by either installing a tailrace barrier or increasing the flow until the home stream odor is sufficient to attract fish. Swimming ability should be the first consideration in fishway design. Fishways with 50 cm drops per pool would be satisfactory in most cases. The problem of headwater fluctuation is overcome through careful fishway selection. Fish locks, hoists, and elevators are other alternatives to pool/weir fishways. The location for a fish exit must be decided on the basis of whether the fishway will be used only for upstream migrations. 5 refs., 1 fig., 1 tab

Comparative physiology and relative swimming performance of three redhorse (Moxostoma spp.) species: associations with fishway passage success.

Science.gov (United States)

Hatry, Charles; Thiem, Jason D; Binder, Thomas R; Hatin, Daniel; Dumont, Pierre; Stamplecoskie, Keith M; Molina, Juan M; Smokorowski, Karen E; Cooke, Steven J

2014-01-01

Our understanding of biological criteria to inform fish passage design is limited, partially due to the lack of understanding of biological motivators, cues, and constraints, as well as a lack of biological performance evaluations of structures once they are built. The Vianney-Legendre vertical slot fishway on the Richelieu River, Quebec, Canada, passes large numbers of migrating redhorse (Moxostoma spp.) upriver to spawning grounds each year. We evaluated the physiological capacity and relative swimming ability of three redhorse species (Moxostoma anisurum, Moxostoma carinatum, Moxostoma macrolepidotum; silver, river, and shorthead redhorse, respectively) to determine how these biotic factors relate to variation in fishway passage success and duration. Shorthead redhorse had higher maximum metabolic rates and were faster swimmers than silver and river redhorse at their species-specific peak migration temperatures. Blood lactate and glucose concentrations recovered more quickly for river redhorse than for silver and shorthead redhorse, and river redhorse placed second in terms of metabolic recovery and swim speed. Interestingly, fish sampled from the top of the fishway had nearly identical lactate, glucose, and pH values compared to control fish. Using passive integrated transponders in 2010 and 2012, we observed that passage success and duration were highly variable among redhorse species and were not consistent among years, suggesting that other factors such as water temperature and river flows may modulate passage success. Clearly, additional research is needed to understand how organismal performance, environmental conditions, and other factors (including abundance of conspecifics and other comigrants) interact with fishway features to dictate which fish will be successful and to inform research of future fishways. Our research suggests that there may be an opportunity for a rapid assessment approach where fish chased to exhaustion to determine maximal values

A semi-automated method of monitoring dam passage of American Eels Anguilla rostrata

Science.gov (United States)

Welsh, Stuart A.; Aldinger, Joni L.

2014-01-01

Fish passage facilities at dams have become an important focus of fishery management in riverine systems. Given the personnel and travel costs associated with physical monitoring programs, automated or semi-automated systems are an attractive alternative for monitoring fish passage facilities. We designed and tested a semi-automated system for eel ladder monitoring at Millville Dam on the lower Shenandoah River, West Virginia. A motion-activated eel ladder camera (ELC) photographed each yellow-phase American Eel Anguilla rostrata that passed through the ladder. Digital images (with date and time stamps) of American Eels allowed for total daily counts and measurements of eel TL using photogrammetric methods with digital imaging software. We compared physical counts of American Eels with camera-based counts; TLs obtained with a measuring board were compared with TLs derived from photogrammetric methods. Data from the ELC were consistent with data obtained by physical methods, thus supporting the semi-automated camera system as a viable option for monitoring American Eel passage. Time stamps on digital images allowed for the documentation of eel passage time—data that were not obtainable from physical monitoring efforts. The ELC has application to eel ladder facilities but can also be used to monitor dam passage of other taxa, such as crayfishes, lampreys, and water snakes.

Acoustic Telemetry Evaluation of Juvenile Salmonid Passage and Survival at John Day Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A.; Woodley, Christa M.; Ploskey, Gene R.; Hughes, James S.; Kim, Jin A.; Deng, Zhiqun; Fu, Tao; Fischer, Eric S.; Skalski, J. R.; Townsend, Richard L.; Duncan, Joanne P.; Hennen, Matthew J.; Wagner, Katie A.; Arntzen, Evan V.; Miller, Benjamin L.; Miracle, Ann L.; Zimmerman, Shon A.; Royer, Ida M.; Khan, Fenton; Cushing, Aaron W.; Etherington, D. J.; Mitchell, T. D.; Elder, T.; Batton, George; Johnson, Gary E.; Carlson, Thomas J.

2013-05-01

This report presents survival, behavioral, and fish passage results for yearling and subyearling Chinook salmon smolts and juvenile steelhead tagged with JSATS acoustic micro-transmitters as part of a survival study conducted at John Day Dam during 2010. This study was designed to evaluate the passage and survival of yearling and subyearling Chinook salmon and juvenile steelhead to assist managers in identifying dam operations for compliance testing as stipulated by the 2008 Federal Columbia River Power System Biological Opinion and the 2008 Columbia Basin Fish Accords. Survival estimates were based on a single-release survival estimate model.

Culvert Length and Interior Lighting Impacts to Topeka Shiner Passage

Science.gov (United States)

2017-11-01

Culverts can act as barriers to fish passage for a number of reasons including insufficient water depth or excess velocity. In addition, concern is being raised over behavioral barriers where culvert conditions elicit an avoidance response that deter...

Evolution of the sensor fish device for measuring physical conditions in sever hydraulic environments

Energy Technology Data Exchange (ETDEWEB)

Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Duncan, J. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2003-03-01

To assist in deriving biological specifications for design of turbine rehabilitation measures, new “fish-friendly” turbines, and spillway designs and operations, Pacific Northwest National Laboratory (PNNL) scientists have developed and tested an autonomous multi-sensor device called a Sensor Fish that can acquire pressure and tri-axial linear acceleration data during passage through severe hydraulic conditions. The purpose of the Sensor Fish is to characterize physical conditions fish experience during passage through hydro turbines, spill stilling basins, high-discharge outfalls, and other dam passage routes. This report discusses the development and field tests of the Sensor Fish at Rock Island, McNary, The Dalles, Bonneville, and Wanapum dams on the Columbia River and the Prosser Irrigation District on the Yakima River, which have shown that the device can withstand the severe environments of turbine, spill, and fish bypass passage and provide useful environmental data that can ultimately aid in the design and operation of new and existing turbines, spill, and dam fish bypass facilities.

Compliance Monitoring of Subyearling Chinook Salmon Smolt Survival and Passage at Bonneville Dam, Summer 2012

Energy Technology Data Exchange (ETDEWEB)

Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.

2013-05-01

The purpose of this compliance study was to estimate dam passage survival of subyearling Chinook salmon at Bonneville Dam during summer 2012, as required by the 2008 Federal Columbia River Power System Biological Opinion. The study also estimated smolt passage survival from the forebay 2 km upstream of the dam to the tailrace 1 km below the dam, as well as forebay residence time, tailrace egress, and spill passage efficiency, as required in the 2008 Columbia Basin Fish Accords.

Hydroacoustic Evaluation of Overwintering Summer Steelhead Fallback and Kelt Passage at The Dalles Dam, 2009-2010

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Johnson, Gary E.; Weiland, Mark A.

2010-07-31

This report presents the results of an evaluation of overwintering summer steelhead (Oncorhynchus mykiss) fallback and early out-migrating steelhead kelts downstream passage at The Dalles Dam (TDA) sluiceway and turbines during fall/winter 2009 through early spring 2010. The study was conducted by the Pacific Northwest National Laboratory (PNNL) for the U.S. Army Corps of Engineers, Portland District (USACE). The goal of this study was to characterize adult steelhead spatial and temporal distributions and passage rates at the sluiceway and turbines for fisheries managers and engineers to use in decision-making relative to sluiceway operations. The study was from November 1, 2009 to April 10, 2010. The study was divided into three study periods: Period 1, November 1 - December 15, 2009 for a fall/winter sluiceway and turbine study; Period 2, December 16, 2009 - February 28, 2010 for a turbine only study; Period 3, March 1 - April 10, 2010 for a spring sluiceway and turbine study. Sluiceway operations were scheduled to begin on March 1 for this study; however, because of an oil spill cleanup near the sluice outfall, sluiceway operations were delayed until March 8, 2010, therefore the spring study period did not commence until March 8. The study objectives were to (1) estimate the number and distribution of overwintering summer steelhead fallbacks and kelt-sized acoustic targets passing into the sluiceway and turbines at TDA between November 1 and December 15, 2009 and March 1 and April 10, 2010, and (2) estimate the numbers and distribution of adult steelhead and kelt-sized targets passing into turbine units between December 16, 2009 and February 28, 2010. We obtained fish passage data using fixed-location hydroacoustics. For Period 1, overwintering summer steelhead fallback occurred throughout the 45-day study period. A total of 879 {+-} 165 (95% CI) steelhead targets passed through the powerhouse and sluiceway during November 1 to December 15, 2009. Ninety two

Improvement of Anadromous Fish Habitat and Passage in Omak Creek, 2008 Annual Report : February 1, 2008 to January 31, 2009.

Energy Technology Data Exchange (ETDEWEB)

Dasher, Rhonda; Fisher, Christopher [Colville Confederated Tribes

2009-06-09

During the 2008 season, projects completed under BPA project 2000-100-00 included installation of riparian fencing, maintenance of existing riparian fencing, monitoring of at-risk culverts and installation of riparian vegetation along impacted sections of Omak Creek. Redd and snorkel surveys were conducted in Omak Creek to determine steelhead production. Canopy closure surveys were conducted to monitor riparian vegetation recovery after exclusion of cattle since 2000 from a study area commonly known as the Moomaw property. Additional redd and fry surveys were conducted above Mission Falls and in the lower portion of Stapaloop Creek to try and determine whether there has been successful passage at Mission Falls. Monitoring adult steelhead trying to navigate the falls resulted in the discovery of shallow pool depth at an upper pool that is preventing many fish from successfully navigating the entire falls. The Omak Creek Habitat and Passage Project has worked with NRCS to obtain additional funds to implement projects in 2009 that will address passage at Mission Falls, culvert replacement, as well as additional riparian planting. The Omak Creek Technical Advisory Group (TAG) is currently revising the Omak Creek Watershed Assessment. In addition, the group is revising strategy to focus efforts in targeted areas to provide a greater positive impact within the watershed. In 2008 the NRCS Riparian Technical Team was supposed to assess areas within the watershed that have unique problems and require special treatments to successfully resolve the issues involved. The technical team will be scheduled for 2009 to assist the TAG in developing strategies for these special areas.

Passage and behaviour of cultured Lake Sturgeon in a prototype side-baffle fish ladder: I. Ladder hydraulics and fish ascent

Science.gov (United States)

Kynard, B.; Pugh, D.; Parker, T.

2011-01-01

Research and development of a fish ladder for sturgeons requires understanding ladder hydraulics and sturgeon behaviour in the ladder to insure the ladder is safe and provides effective passage. After years of research and development, we designed and constructed a full-scale prototype side-baffle ladder inside a spiral flume (38.3m long??1m wide??1m high) on a 6% (1:16.5) slope with a 1.92-m rise in elevation (bottom to top) to test use by sturgeons. Twenty-eight triangular side baffles, each extending part way across the flume, alternated from inside wall to outside wall down the ladder creating two major flow habitats: a continuous, sinusoidal flow down the ladder through the vertical openings of side-baffles and an eddy below each side baffle. Ascent and behaviour was observed on 22 cultured Lake Sturgeon=LS (Acipenser fulvescens) repeatedly tested in groups as juveniles (as small as 105.1cm TL, mean) or as adults (mean TL, 118cm) during four periods (fall 2002 and 2003; spring 2003 and 2007). Percent of juveniles entering the ladder that ascended to the top was greater in spring (72.7%) than in fall (40.9-45.5%) and 90.9% of 11 adults, which ascended as juveniles, ascended to the top. Six LS (27.3%) never swam to the top and seven (31.8%) swam to the top in all tests, indicating great variability among individuals for ascent drive. Some LS swam directly to the top in <1min, but most rested in an eddy during ascent. Juveniles swimming through outside wall baffle slots (mean velocity, 1.2ms-1) swam at 1.8-2.2body lengthss-1 and 3.2-3.3tail beatss-1, either at or approaching prolonged swimming speed. The side-baffle ladder was stream-like and provided key factors for a sturgeon ladder: a continuous flow and no full cross-channel walls, abundant eddies for resting, an acceptable water depth, and a water velocity fish could ascend swimming 2bls-1. A side-baffle ladder passes LS and other moderate-swimming fishes. ?? 2011 Blackwell Verlag, Berlin.

Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project, Annual Report 2002-2003.

Energy Technology Data Exchange (ETDEWEB)

Sears, Sheryl

2004-01-01

The construction of Chief Joseph and Grand Coulee Dams completely and irrevocably blocked anadromous fish migrations to the Upper Columbia River. Historically this area hosted vast numbers of salmon returning to their natal waters to reproduce and die. For the native peoples of the region, salmon and steelhead were a principle food source, providing physical nourishment and spiritual sustenance, and contributing to the religious practices and the cultural basis of tribal communities. The decaying remains of spawned-out salmon carcasses contributed untold amounts of nutrients into the aquatic, aerial, and terrestrial ecosystems of tributary habitats in the upper basin. Near the present site of Kettle Falls, Washington, the second largest Indian fishery in the state existed for thousands of years. Returning salmon were caught in nets and baskets or speared on their migration to the headwater of the Columbia River in British Columbia. Catch estimates at Kettle Falls range from 600,000 in 1940 to two (2) million around the turn of the century (UCUT, Report No.2). The loss of anadromous fish limited the opportunities for fisheries management and enhancement exclusively to those actions addressed to resident fish. The Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project is a mitigation project intended to enhance resident fish populations and to partially mitigate for anadromous fish losses caused by hydropower system impacts. This substitution of resident fish for anadromous fish losses is considered in-place and out-of-kind mitigation. Upstream migration and passage barriers limit the amount of spawning and rearing habitat that might otherwise be utilized by rainbow trout. The results of even limited stream surveys and habitat inventories indicated that a potential for increased natural production exists. However, the lack of any comprehensive enhancement measures prompted the Upper Columbia United Tribes Fisheries Center (UCUT), Colville Confederated

Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project, Annual Report 2001-2002.

Energy Technology Data Exchange (ETDEWEB)

Sears, Sheryl

2003-01-01

The construction of Chief Joseph and Grand Coulee Dams completely and irrevocably blocked anadromous fish migrations to the Upper Columbia River. Historically this area hosted vast numbers of salmon returning to their natal waters to reproduce and die. For the native peoples of the region, salmon and steelhead were a principle food source, providing physical nourishment and spiritual sustenance, and contributing to the religious practices and the cultural basis of tribal communities. The decaying remains of spawned-out salmon carcasses contributed untold amounts of nutrients into the aquatic, aerial, and terrestrial ecosystems of tributary habitats in the upper basin. Near the present site of Kettle Falls, Washington, the second largest Indian fishery in the state existed for thousands of years. Returning salmon were caught in nets and baskets or speared on their migration to the headwater of the Columbia River in British Columbia. Catch estimates at Kettle Falls range from 600,000 in 1940 to two (2) million around the turn of the century (UCUT, Report No.2). The loss of anadromous fish limited the opportunities for fisheries management and enhancement exclusively to those actions addressed to resident fish. The Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project is a mitigation project intended to enhance resident fish populations and to partially mitigate for anadromous fish losses caused by hydropower system impacts. This substitution of resident fish for anadromous fish losses is considered in-place and out-of-kind mitigation. Upstream migration and passage barriers limit the amount of spawning and rearing habitat that might otherwise be utilized by rainbow trout. The results of even limited stream surveys and habitat inventories indicated that a potential for increased natural production exists. However, the lack of any comprehensive enhancement measures prompted the Upper Columbia United Tribes Fisheries Center (UCUT), Colville Confederated

Estimating reach-specific fish movement probabilities in rivers with a Bayesian state-space model: application to sea lamprey passage and capture at dams

Science.gov (United States)

Holbrook, Christopher M.; Johnson, Nicholas S.; Steibel, Juan P.; Twohey, Michael B.; Binder, Thomas R.; Krueger, Charles C.; Jones, Michael L.

2014-01-01

Improved methods are needed to evaluate barriers and traps for control and assessment of invasive sea lamprey (Petromyzon marinus) in the Great Lakes. A Bayesian state-space model provided reach-specific probabilities of movement, including trap capture and dam passage, for 148 acoustic tagged invasive sea lamprey in the lower Cheboygan River, Michigan, a tributary to Lake Huron. Reach-specific movement probabilities were combined to obtain estimates of spatial distribution and abundance needed to evaluate a barrier and trap complex for sea lamprey control and assessment. Of an estimated 21 828 – 29 300 adult sea lampreys in the river, 0%–2%, or 0–514 untagged lampreys, could have passed upstream of the dam, and 46%–61% were caught in the trap. Although no tagged lampreys passed above the dam (0/148), our sample size was not sufficient to consider the lock and dam a complete barrier to sea lamprey. Results also showed that existing traps are in good locations because 83%–96% of the population was vulnerable to existing traps. However, only 52%–69% of lampreys vulnerable to traps were caught, suggesting that traps can be improved. The approach used in this study was a novel use of Bayesian state-space models that may have broader applications, including evaluation of barriers for other invasive species (e.g., Asian carp (Hypophthalmichthys spp.)) and fish passage structures for other diadromous fishes.

Evolution of the Sensor Fish Device for Measuring Physical Conditions in Severe Hydraulic Environments

Energy Technology Data Exchange (ETDEWEB)

Carlson, Thomas J.; Duncan, Joanne P.

2003-02-28

To assist in deriving biological specifications for design of turbine rehabilitation measures, new ''fish-friendly'' turbines, and spillway designs and operations, scientists at the Pacific Northwest National Laboratory (PNNL) have developed and tested an autonomous multi-sensor device called a Sensor Fish that can acquire pressure and tri-axial linear acceleration data during passage through severe hydraulic conditions. The purpose of the Sensor Fish is to characterize physical conditions fish experience during passage through hydro turbines, spill stilling basins, high-discharge outfalls, and other dam passage routes. The Sensor Fish was developed with the support of the U.S. Department of Energy's Advanced Hydropower Turbine System program. Field tests of the Sensor Fish at Rock Island, McNary, The Dalles, Bonneville, and Wanapum dams on the Columbia River and the Prosser Irrigation District on the Yakima River have shown that the device can withstand the severe environments of turbine, spill, and fish bypass passage and provide useful environmental data that can ultimately aid in the design and operation of new and existing turbines, spill, and dam fish bypass facilities.

Fish Passage Center 2000 annual report.; ANNUAL

International Nuclear Information System (INIS)

Fish Passage Center

2001-01-01

The year 2000 hydrosystem operations illustrated two main points: (1) that the NMFS Biological Opinion on the operations of the Federal Columbia River Power System (FCRPS) fish migration measures could not be met in a slightly below average water year, and; (2) the impacts and relationships of energy deregulation and volatile wholesale energy prices on the ability of the FCRPS to provide the Biological Opinion fish migration measures. In 2000, a slightly below average water year, the flow targets were not met and, when energy ''emergencies'' were declared, salmon protection measures were reduced. The 2000 migration year was a below average runoff volume year with an actual run off volume of 61.1 MAF or 96% of average. This year illustrated the ability of the hydro system to meet the migration protection measures established by the NMFS Biological Opinion. The winter operation of storage reservoirs was based upon inaccurate runoff volume forecasts which predicted a January-July runoff volume forecast at The Dalles of 102 to 105% of average, from January through June. Reservoir flood control drafts during the winter months occurred according to these forecasts. This caused an over-draft of reservoirs that resulted in less volume of water available for fish flow augmentation in the spring and the summer. The season Biological Opinion flow targets for spring and summer migrants at Lower Granite and McNary dams were not met. Several power emergencies were declared by BPA in the summer of 2000. The first in June was caused by loss of resources (WNP2 went off-line). The second and third emergencies were declared in August as a result of power emergencies in California and in the Northwest. The unanticipated effects of energy deregulation, power market volatility and rising wholesale electricity prices, and Californian energy deregulation reduced the ability of the FCRPS to implement fish protection measures. A Spill Plan Agreement was implemented in the FCRPS. Under this

Reduced Spill at Hydropower Dams: Opportunities for More Generation and Increased Fish Population

Energy Technology Data Exchange (ETDEWEB)

Coutant, Charles C [ORNL; Mann, Roger [RMecon, Davis, California; Sale, Michael J [ORNL

2006-09-01

This report indicates that reduction of managed spill at hydropower dams can speed implementation of technologies for fish protection and achieve economic goals. Spill of water over spillways is managed in the Columbia River basin to assist downstream-migrating juvenile salmon, and is generally believed to be the most similar to natural migration, benign and effective passage route; other routes include turbines, intake screens with bypasses, and surface bypasses. However, this belief may be misguided, because spill is becoming recognized as less than natural, with deep intakes below normal migration depths, and likely causing physical damages from severe shear on spillways, high turbulence in tail waters, and collisions with baffle blocks that lead to disorientation and predation. Some spillways induce mortalities comparable to turbines. Spill is expensive in lost generation, and controversial. Fish-passage research is leading to more fish-friendly turbines, screens and bypasses that are more effective and less damaging, and surface bypasses that offer passage of more fish per unit water volume than does spill (leaving more water for generation). Analyses by independent economists demonstrated that goals of increased fish survival over the long term and net gain to the economy can be obtained by selectively reducing spill and diverting some of the income from added power generation to research, development, and installation of fish-passage technologies. Such a plan would selectively reduce spill when and where least damaging to fish, increase electricity generation using the water not spilled and use innovative financing to direct monetary gains to improving fish passage.

Passage survival of juvenile steelhead, coho salmon, and Chinook salmon in Lake Scanewa and at Cowlitz Falls Dam, Cowlitz River, Washington, 2010–16

Science.gov (United States)

Liedtke, Theresa L.; Kock, Tobias J.; Hurst, William

2018-04-03

A multi-year evaluation was conducted during 2010–16 to evaluate passage survival of juvenile steelhead (Oncorhynchus mykiss), Chinook salmon (O. tshawytscha), and coho salmon (O. kisutch) in Lake Scanewa, and at Cowlitz Falls Dam in the upper Cowlitz River Basin, Washington. Reservoir passage survival was evaluated in 2010, 2011, and 2016, and included the tagging and release of 1,127 juvenile salmonids. Tagged fish were released directly into the Cowlitz and Cispus Rivers, 22.3 and 8.9 km, respectively, upstream of the reservoir, and were monitored as they moved downstream into, and through the reservoir. A single release-recapture survival model was used to analyze detection records and estimate reservoir passage survival, which was defined as successful passage from reservoir entry to arrival at Cowlitz Falls Dam. Tagged fish generally moved quickly downstream of the release sites and, on average, arrived in the dam forebay within 2 d of release. Median travel time from release to first detection at the dam ranged from 0.23 to 0.96 d for juvenile steelhead, from 0.15 to 1.11 d for juvenile coho salmon, and from 0.18 to 1.89 d for juvenile Chinook salmon. Minimum reservoir passage survival probabilities were 0.960 for steelhead, 0.855 for coho salmon and 0.900 for Chinook salmon.Dam passage survival was evaluated at the pilot-study level during 2013–16 and included the tagging and release of 2,512 juvenile salmonids. Juvenile Chinook salmon were evaluated during 2013–14, and juvenile steelhead and coho salmon were evaluated during 2015–16. A paired-release study design was used that included release sites located upstream and downstream of Cowlitz Falls Dam. The downstream release site was positioned at the downstream margin of the dam’s tailrace, which allowed dam passage survival to be measured in a manner that included mortality that occurred in the passage route and in the dam tailrace. More than one-half of the tagged Chinook salmon (52 percent

Evaluation of Behavioral Guidance Structure on Juvenile Salmonid Passage and Survival at Bonneville Dam in 2009

Energy Technology Data Exchange (ETDEWEB)

Faber, Derrek M.; Ploskey, Gene R.; Weiland, Mark A.; Deng, Zhiqun; Hughes, James S.; Kim, Jin A.; Fu, Tao; Fischer, Eric S.; Monter, Tyrell J.; Skalski, J. R.

2011-03-01

Pacific Northwest National Laboratory (PNNL) conducted an acoustic-telemetry study at Bonneville Dam in 2009 to evaluate the effects of a behavioral guidance structure (BGS) in the Bonneville Dam second powerhouse forebay on fish passage and survival through the second powerhouse (B2), the dam as a whole, and through the first powerhouse and spillway combined. The BGS was deployed to increase the survival of fish passing through B2 by increasing the percentage of outmigrating smolts entering the B2 Corner Collector (B2CC)—a surface flow outlet known to be a relatively benign route for downstream passage at this dam. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. Study results indicated that having turbine 11 in service is important for providing flow conditions that are comparable to those observed in pre-BGS years (2004 and 2005) and in 2008. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Hydroacoustic Evaluation of Overwintering Summer Steelhead Fallback and Kelt Passage at The Dalles Dam Turbines, Early Spring 2011

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Royer, Ida M.

2012-02-01

This report presents the results of an evaluation of overwintering summer steelhead (Oncorhynchus mykiss) fallback and early out-migrating steelhead kelts downstream passage at The Dalles Dam turbines during early spring 2011. The study was conducted by Pacific Northwest National Laboratory (PNNL) for the U.S. Army Corps of Engineers, Portland District (USACE) to investigate whether adult steelhead are passing through turbines during early spring before annual sluiceway operations typically begin. The sluiceway surface flow outlet is the optimal non-turbine route for adult steelhead, although operating the sluiceway reduces hydropower production. This is a follow-up study to similar studies of adult steelhead passage at the sluiceway and turbines we conducted in the fall/winter 2008, early spring 2009, fall/winter 2009, and early spring 2010. The goal of the 2011 study was to characterize adult steelhead passage rates at the turbines while the sluiceway was closed so fisheries managers would have additional information to use in decision-making relative to sluiceway operations. Sluiceway operations were not scheduled to begin until April 10, 2011. However, based on a management decision in late February, sluiceway operations commenced on March 1, 2011. Therefore, this study provided estimates of fish passage rates through the turbines, and not the sluiceway, while the sluiceway was open. The study period was March 1 through April 10, 2011 (41 days total). The study objective was to estimate the number and distribution of adult steelhead and kelt-sized targets passing into turbine units. We obtained fish passage data using fixed-location hydroacoustics with transducers deployed at all 22 main turbine units at The Dalles Dam. Adult steelhead passage through the turbines occurred on 9 days during the study (March 9, 12, 30, and 31 and April 2, 3, 5, 7, and 9). We estimated a total of 215 {+-} 98 (95% confidence interval) adult steelhead targets passed through the

Evaluation of juvenile salmonid bypass facilities and passage at water diversions on the lower Umatilla River. Final report

International Nuclear Information System (INIS)

Cameron, W.A.; Knapp, S.M.; Carmichael, R.W.

1997-07-01

Outdated juvenile and adult fish passage facilities were recently reconstructed at the five major irrigation dams on the lower Umatilla River, Oregon to meet National marine Fisheries Service (NMFS) design standards. Changes in design at juvenile fish bypass facilities included reduced mesh size on the rotating drum screens, larger screening area, a more oblique orientation of the drum screens to canal flow, improved screen seals, replacement of bypass portals with vertical slot bypass channels, and increased bypass pipe diameters. Weir-and-pool adult fish ladders and jump pools were replaced with vertical-slot ladders. From 1991--1995, they investigated injury and travel rate of juvenile fish moving through the facilities, and efficiency of screens in preventing fish entry into the canals. Water velocities in front of canal screens, at bypass channel entrances, and at ladder diffusers were measured to assess adherence to NMFS criteria and identify hydraulic patterns. Biological evaluations were conducted by releasing and recapturing marked yearling summer steelhead (Oncorhynchus mykiss), yearling spring chinook salmon (O. tshawytscha), and subyearling fall chinook salmon (O. tshawytscha) in varying locations within the fish passage facilities

Fixed-location hydroacoustic monitoring designs for estimating fish passage using stratified random and systematic sampling

International Nuclear Information System (INIS)

Skalski, J.R.; Hoffman, A.; Ransom, B.H.; Steig, T.W.

1993-01-01

Five alternate sampling designs are compared using 15 d of 24-h continuous hydroacoustic data to identify the most favorable approach to fixed-location hydroacoustic monitoring of salmonid outmigrants. Four alternative aproaches to systematic sampling are compared among themselves and with stratified random sampling (STRS). Stratifying systematic sampling (STSYS) on a daily basis is found to reduce sampling error in multiday monitoring studies. Although sampling precision was predictable with varying levels of effort in STRS, neither magnitude nor direction of change in precision was predictable when effort was varied in systematic sampling (SYS). Furthermore, modifying systematic sampling to include replicated (e.g., nested) sampling (RSYS) is further shown to provide unbiased point and variance estimates as does STRS. Numerous short sampling intervals (e.g., 12 samples of 1-min duration per hour) must be monitored hourly using RSYS to provide efficient, unbiased point and interval estimates. For equal levels of effort, STRS outperformed all variations of SYS examined. Parametric approaches to confidence interval estimates are found to be superior to nonparametric interval estimates (i.e., bootstrap and jackknife) in estimating total fish passage. 10 refs., 1 fig., 8 tabs

Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2000 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

DeHart, Michele (Columbia Basin Fish and Wildlife Authority, Fish Passage Center, Portland, OR)

2001-06-01

The year 2000 hydrosystem operations illustrated two main points: (1) that the NMFS Biological Opinion on the operations of the Federal Columbia River Power System (FCRPS) fish migration measures could not be met in a slightly below average water year, and; (2) the impacts and relationships of energy deregulation and volatile wholesale energy prices on the ability of the FCRPS to provide the Biological Opinion fish migration measures. In 2000, a slightly below average water year, the flow targets were not met and, when energy ''emergencies'' were declared, salmon protection measures were reduced. The 2000 migration year was a below average runoff volume year with an actual run off volume of 61.1 MAF or 96% of average. This year illustrated the ability of the hydro system to meet the migration protection measures established by the NMFS Biological Opinion. The winter operation of storage reservoirs was based upon inaccurate runoff volume forecasts which predicted a January-July runoff volume forecast at The Dalles of 102 to 105% of average, from January through June. Reservoir flood control drafts during the winter months occurred according to these forecasts. This caused an over-draft of reservoirs that resulted in less volume of water available for fish flow augmentation in the spring and the summer. The season Biological Opinion flow targets for spring and summer migrants at Lower Granite and McNary dams were not met. Several power emergencies were declared by BPA in the summer of 2000. The first in June was caused by loss of resources (WNP2 went off-line). The second and third emergencies were declared in August as a result of power emergencies in California and in the Northwest. The unanticipated effects of energy deregulation, power market volatility and rising wholesale electricity prices, and Californian energy deregulation reduced the ability of the FCRPS to implement fish protection measures. A Spill Plan Agreement was implemented in

Performance of a surface bypass structure to enhance juvenile steelhead passage and survival at Lower Granite Dam, Washington

Science.gov (United States)

Adams, Noah S.; Plumb, John M.; Perry, Russell W.; Rondorf, Dennis W.

2014-01-01

An integral part of efforts to recover stocks of Pacific salmon Oncorhynchus spp. and steelhead O. mykiss in Pacific Northwest rivers is to increase passage efficacy and survival of juveniles past hydroelectric dams. As part of this effort, we evaluated the efficacy of a prototype surface bypass structure, the removable spillway weir (RSW), installed in a spillbay at Lower Granite Dam, Washington, on the Snake River during 2002, 2003, 2005, and 2006. Radio-tagged juvenile steelhead were released upstream from the dam and their route of passage through the turbines, juvenile bypass, spillway, or RSW was recorded. The RSW was operated in an on-or-off condition and passed 3–13% of the total discharge at the dam when it was on. Poisson rate models were fit to the passage counts of hatchery- and natural-origin juvenile steelhead to predict the probability of fish passing the dam. Main-effect predictor variables were RSW operation, diel period, day of the year, proportion of flow passed by the spillway, and total discharge at the dam. The combined fish passage through the RSW and spillway was 55–85% during the day and 37–61% during the night. The proportion of steelhead passing through nonturbine routes was 95% when the RSW was on during the day. The ratio of the proportion of steelhead passed to the proportion of water passing the RSW was from 6.3:1 to 10.0:1 during the day and from 2.7:1 to 5.2:1 during the night. Steelhead passing through the RSW exited the tailrace about 15 min faster than fish passing through the spillway. Mark–recapture single-release survival estimates for steelhead passing the RSW ranged from 0.95 to 1.00. The RSW appeared to be an effective bypass structure compared with other routes of fish passage at the dam.

Hydroacoustic Evaluation of Juvenile Salmonid Passage at The Dalles Dam in 2004

International Nuclear Information System (INIS)

Johnson, Gary E.; Hanks, Michael E.; Khan, Fenton; Cook, Chris B.; Hedgepeth, J.; Mueller, Robert P.; Rakowski, Cynthia L.; Richmond, Marshall C.; Sargeant, Susan L.; Serkowski, John A.; Skalski, John R.

2005-01-01

The U.S. Army Corps of Engineers Portland District engaged the Pacific Northwest National Laboratory to evaluate juvenile salmon passage at The Dalles Dam in 2004 to inform decisions about long-term measures and operations to enhance sluiceway and spill passage and reduce turbine passage to improve smolt survival at the dam. PNNL used fixed-location hydroacoustic sampling across the entire project, especially at the sluiceway and spillway, using multiple split-beam transducers at selected locations. At the sluiceway nearfield, we used an acoustic camera to track fish. The fish data were interpreted and integrated with hydraulic data from a CFD model and in-field ADCP measurements. Two sluiceway operations were compared: West only (SL 1) vs. West+East (SL 1 + SL 18). Based on our findings, we concluded that The Dalles Dam sluiceway has the potential to be highly efficient and effective at passing juvenile salmonids. This potential could be tapped with hydraulic and entrance enhancements to the sluiceway. We recommended the following: (1) six rather than three sluice gates should be opened to take advantage of the maximum hydraulic capacity of the sluiceway. (2) The turbine units below open sluice gates should be operated as a standard fish operations procedure. (3) In 2005, the Corps and fisheries agencies should consider operating sluice gates in one or more of the following combinations of six gates: (a) SL 1-1, 1-2, 1-3 and SL 18-1, 18-2, 18-3 (repeat 2004 operation), (b) SL 1-1, 1-2, 1-3 and SL 11-1, 11-2, 11-3, or (c) SL 1-1, 1-2, 1-3 and SL 2-1, 2-2, 2-3. The following elements for surface flow bypasses which should be considered during design of any sluiceway enhancements at The Dalles Dam: (1) form an extensive surface flow bypass flow net (surface bypass discharge greater than ∼7% of total project discharge), (2) create a gradual increase in water velocity approaching the surface flow bypass (ideally, acceleration 3 m/s) to entrain the subject juvenile

The Effect of an Externally Attached Neutrally Buoyant Transmitter on Mortal Injury during Simulated Hydroturbine Passage

Energy Technology Data Exchange (ETDEWEB)

Brown, Richard S.; Pflugrath, Brett D.; Carlson, Thomas J.; Deng, Zhiqun

2012-02-03

On their seaward migration, juvenile salmonids commonly pass hydroelectric dams. Fish passing through hydroturbines experience a rapid decrease in pressure as they pass by the turbine blade and the severity of this decompression can be highly variable. This rapid decrease in pressure can result in injuries such as swim bladder rupture, exophthalmia, and emboli and hemorrhaging in the fins and tissues. However, recent research indicates that the presence of a telemetry tag (acoustic, radio, inductive) implanted inside the coelom of a juvenile salmon increases the likelihood that the fish will be injured or die during turbine passage. Thus, previous research conducted using telemetry tags implanted into the coelom of fish may have been inaccurate. Thus, a new technique is needed to provide unbiased estimates of survival through turbines. This research provides an evaluation of the effectiveness of a neutrally buoyant externally attached acoustic transmitter. Both nontagged fish and fish tagged with a neutrally buoyant external transmitter were exposed to a range of rapid decompressions simulating turbine passage. Juvenile Chinook salmon tagged with a neutrally buoyant externally attached acoustic transmitter did not receive a higher degree of barotrauma than their nontagged counterparts. We suggest that future research include field-based comparisons of survival and behavior among fish tagged with a neutrally buoyant external transmitter and those internally implanted with transmitters.

Washington Phase II Fish Diversion Screen Evaluations in the Yakima River Basin, 2004-2005 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Vucelick, Jessica; McMichael, Geoffrey; Chamness, Mickie [Pacific Northwest National Laboratory

2006-02-01

In 2004, the Pacific Northwest National Laboratory (PNNL) evaluated 25 Phase II fish screen sites in the Yakima River Basin as part of a multi-year project for the Bonneville Power Administration on the effectiveness of fish screening devices. PNNL collected data to determine whether velocities in front of the screens and in the bypasses met the National Oceanic and Atmospheric Administration Fisheries (NOAA Fisheries, formerly the National Marine Fisheries Service (NMFS)) criteria to promote safe and timely fish passage. In addition, PNNL conducted underwater video surveys to evaluate the environmental and operational conditions of the screen sites with respect to fish passage. Based on evaluations in 2004, PNNL concluded that: (1) In general, water velocity conditions at the screen sites met fish passage criteria set by NOAA Fisheries. (2) Conditions at most facilities would be expected to provide for safe juvenile fish passage. (3) Automated cleaning brushes generally functioned properly; chains and other moving parts were typically well-greased and operative. (4) Removal of sediment buildup and accumulated leafy and woody debris could be improved at some sites. (5) Conditions at some facilities indicate that operation and/or maintenance should be modified to improve passage conditions for juvenile fish. For example, Taylor has had problems meeting bypass flow and submergence operating criteria since the main river channel shifted away from the site 2 years ago, and Fruitvale consistently has had problems meeting bypass flow criteria when the water is low. (6) Continued problems at Gleed point to design flaws. This site should be considered for redesign or replacement.

Fish Passage Through Dams on the Upper Mississippi River

National Research Council Canada - National Science Library

Wilcox, Daniel

1999-01-01

.... I identified UMR migratory fish species, estimated current velocities through gate openings on UMR dams, compiled information on migration behavior, and estimated the swimming for north performance...

Physiological responses of adult rainbow trout experimentally released through a unique fish conveyance device

Science.gov (United States)

Mesa, Matthew G.; Gee, Lisa P.; Weiland, Lisa K.; Christiansen, Helena E.

2013-01-01

We assessed the physiological stress responses (i.e., plasma levels of cortisol, glucose, and lactate) of adult Rainbow Trout Oncorhynchus mykiss at selected time intervals after they had passed a distance of 15 m through a unique fish conveyance device (treatment fish) or not (controls). This device differs from traditional fish pumps in two important ways: (1) it transports objects in air, rather than pumping them from and with water; and (2) it uses a unique tube for transport that has a series of soft, deformable baffles spaced evenly apart and situated perpendicular within a rigid, but flexible outer shell. Mean concentrations of the plasma constituents never differed (P > 0.05) between control and treatment fish at 0, 1, 4, 8, or 24 h after passage, and only minor differences were apparent between the different time intervals within a group. We observed no obvious injuries on any of our fish. Our results indicate that passage through this device did not severely stress or injure fish and it may allow for the rapid and safe movement of fish at hatcheries, sorting or handling facilities, or passage obstacles.

Fish and hydroelectricity

International Nuclear Information System (INIS)

Zorpette, G.

1990-01-01

This paper reports on the problems that hydroelectric plants have regarding fish populations. The utilities that operate these plants are finding that accommodating migrating fish presents unique engineering challenges, not the least of which involves designing and building systems to protect fish species whose migratory behavior remains something of a mystery. Where such systems cannot be built, the status of hydroelectric dams may be in doubt, as is now the case with several dams in the United States. A further twist in some regions in the possibility that certain migratory fish will be declared threatened or endangered-a development that could wreak havoc on the hydroelectric energy supply in those regions

Evaluation of Boundary Dam spillway using an Autonomous Sensor Fish Device

Energy Technology Data Exchange (ETDEWEB)

Deng, Z. D.; Duncan, J. P.; Arnold, J. L.; Fu, T.; Martinez, J.; Lu, J.; Titzler, P. S.; Zhou, D.; Mueller, R. P.

2017-03-01

Fish passage conditions over spillways are important for the operations of hydroelectric dams because spillways are usually considered as a common alternative passage route to divert fish from the turbines. The objectives of this study were to determine the relative potential of fish injury during spillway passage both before and after the installation of baffle blocks at Boundary Dam, and to provide validation data for a model being used to predict total dissolved gas levels. Sensor Fish were deployed through a release system mounted on the face of the dam in the forebay. Three treatments, based on the lateral position on the spillway, were evaluated for both the baseline and post-modification evaluations: Left Middle, Right Middle, and Right. No significant acceleration events were detected in the forebay, gate, or transition regions for any release location; events were only observed on the chute and in the tailrace. Baseline acceleration events observed in the chute region were all classified as strikes, whereas post-modification events included strike and shear on the chute. While the addition of baffle blocks increased the number of significant events observed on the spillway chute, overall fewer events were observed in the tailrace post-modification. Analysis of lateral positioning of passage indicated that the Right Middle treatment was potentially less injurious to fish based on relative frequency of significant events at each location. The construction of baffle blocks on the spillway visibly changed the flow regime. Prior to installation the flow jet was relatively thin, impacting the tailrace as a coherent stream that plunged deeply, possibly contributing to total dissolved gas production. Following baffle block construction, the discharge jet was more fragmented, potentially disrupting the plunge depth and decreasing the time that bubbles would be at depth in the plunge pool. The results in this study support the expected performance of the modified

Sensitivity of the downward to sweeping velocity ratio to the bypass flow percentage along a guide wall for downstream fish passage

Science.gov (United States)

Mulligan, Kevin; Towler, Brett; Haro, Alexander J.; Ahlfeld, David P.

2017-01-01

Partial-depth impermeable guidance structures (or guide walls) are used as a method to assist in the downstream passage of fish at a hydroelectric facility. However, guide walls can result in a strong downward velocity causing the approaching fish to pass below the wall and into the direction of the turbine intakes. The objective of this study was to describe how the ratio of the vertical velocity to the sweeping velocity magnitude changes along the full length and depth of a guide wall under a wide range of bypass flow percentages within a power canal. This paper focused on two guide wall configurations, each set at an angle of 45 ° to the approaching flow field and at a depth of 10 and 20 ft (3.05 and 6.10 m). The hydraulic conditions upstream of each guide wall configuration were shown to be impacted by a change in the bypass flow percentage, not only near the bypass but also at upstream sections of the guide wall. Furthermore, the effect of changing the bypass flow percentage was similar for both guide wall depths. In both cases, the effect of increasing the bypass flow percentage was magnified closer to the bypass and deeper in the water column along the guide wall.

Differences in the Stimulus Accommodative Convergence/Accommodation Ratio using Various Techniques and Accommodative Stimuli.

Science.gov (United States)

Satou, Tsukasa; Ito, Misae; Shinomiya, Yuma; Takahashi, Yoshiaki; Hara, Naoto; Niida, Takahiro

2018-04-04

To investigate differences in the stimulus accommodative convergence/accommodation (AC/A) ratio using various techniques and accommodative stimuli, and to describe a method for determining the stimulus AC/A ratio. A total of 81 subjects with a mean age of 21 years (range, 20-23 years) were enrolled. The relationship between ocular deviation and accommodation was assessed using two methods. Ocular deviation was measured by varying the accommodative requirement using spherical plus/minus lenses to create an accommodative stimulus of 10.00 diopters (D) (in 1.00 D steps). Ocular deviation was assessed using the alternate prism cover test in method 1 at distance (5 m) and near (1/3 m), and the major amblyoscope in method 2. The stimulus AC/A ratios obtained using methods 1 and 2 were calculated and defined as the stimulus AC/A ratios with low and high accommodation, respectively, using the following analysis method. The former was calculated as the difference between the convergence response to an accommodative stimulus of 3 D and 0 D, divided by 3. The latter was calculated as the difference between the convergence response to a maximum (max) accommodative stimulus with distinct vision of the subject and an accommodative stimulus of max minus 3.00 D, divided by 3. The median stimulus AC/A ratio with low accommodation (1.0 Δ/D for method 1 at distance, 2.0 Δ/D for method 1 at near, and 2.7 Δ/D for method 2) differed significantly among the measurement methods (P accommodation (4.0 Δ/D for method 1 at distance, 3.7 Δ/D for method 1 at near, and 4.7 Δ/D for method 2) between method 1 at distance and method 2 were statistically significant (P accommodative stimuli. However, differences caused by measurement technique may be reduced by using a high accommodative stimulus during measurements.

A field evaluation of an external and neutrally buoyant acoustic transmitter for juvenile salmon: implications for estimating hydroturbine passage survival.

Directory of Open Access Journals (Sweden)

Richard S Brown

Full Text Available Turbine-passed fish are exposed to rapid decreases in pressure which can cause barotrauma. The presence of an implanted telemetry tag increases the likelihood of injury or death from exposure to pressure changes, thus potentially biasing studies evaluating survival of turbine-passed fish. Therefore, a neutrally buoyant externally attached tag was developed to eliminate this bias in turbine passage studies. This new tag was designed not to add excess mass in water or take up space in the coelom, having an effective tag burden of zero with the goal of reducing pressure related biases to turbine survival studies. To determine if this new tag affects fish performance or susceptibility to predation, it was evaluated in the field relative to internally implanted acoustic transmitters (JSATS; Juvenile Salmon Acoustic Telemetry System used widely for survival studies of juvenile salmonids. Survival and travel time through the study reach was compared between fish with either tag type in an area of high predation in the Snake and Columbia rivers, Washington. An additional group of fish affixed with neutrally-buoyant dummy external tags were implanted with passive integrated transponder (PIT tags and recovered further downstream to assess external tag retention and injury. There were no significant differences in survival to the first detection site, 12 river kilometers (rkm downstream of release. Travel times were also similar between groups. Conversely, externally-tagged fish had reduced survival (or elevated tag loss to the second detection site, 65 rkm downstream. In addition, the retention study revealed that tag loss was first observed in fish recaptured approximately 9 days after release. Results suggest that this new tag may be viable for short term (<8 days single-dam turbine-passage studies and under these situations, may alleviate the turbine passage-related bias encountered when using internal tags, however further research is needed to

A field evaluation of an external and neutrally buoyant acoustic transmitter for juvenile salmon: implications for estimating hydroturbine passage survival.

Science.gov (United States)

Brown, Richard S; Deng, Z Daniel; Cook, Katrina V; Pflugrath, Brett D; Li, Xinya; Fu, Tao; Martinez, Jayson J; Li, Huidong; Trumbo, Bradly A; Ahmann, Martin L; Seaburg, Adam G

2013-01-01

Turbine-passed fish are exposed to rapid decreases in pressure which can cause barotrauma. The presence of an implanted telemetry tag increases the likelihood of injury or death from exposure to pressure changes, thus potentially biasing studies evaluating survival of turbine-passed fish. Therefore, a neutrally buoyant externally attached tag was developed to eliminate this bias in turbine passage studies. This new tag was designed not to add excess mass in water or take up space in the coelom, having an effective tag burden of zero with the goal of reducing pressure related biases to turbine survival studies. To determine if this new tag affects fish performance or susceptibility to predation, it was evaluated in the field relative to internally implanted acoustic transmitters (JSATS; Juvenile Salmon Acoustic Telemetry System) used widely for survival studies of juvenile salmonids. Survival and travel time through the study reach was compared between fish with either tag type in an area of high predation in the Snake and Columbia rivers, Washington. An additional group of fish affixed with neutrally-buoyant dummy external tags were implanted with passive integrated transponder (PIT) tags and recovered further downstream to assess external tag retention and injury. There were no significant differences in survival to the first detection site, 12 river kilometers (rkm) downstream of release. Travel times were also similar between groups. Conversely, externally-tagged fish had reduced survival (or elevated tag loss) to the second detection site, 65 rkm downstream. In addition, the retention study revealed that tag loss was first observed in fish recaptured approximately 9 days after release. Results suggest that this new tag may be viable for short term (<8 days) single-dam turbine-passage studies and under these situations, may alleviate the turbine passage-related bias encountered when using internal tags, however further research is needed to confirm this.

Ammonia production, excretion, toxicity, and defense in fish: A Review

Directory of Open Access Journals (Sweden)

Alex Y K Ip

2010-10-01

Full Text Available Many fishes are ammonotelic but some species can detoxify ammonia to glutamine or urea. Certain fish species can accumulate high levels of ammonia in the brain or defense against ammonia toxicity by enhancing the effectiveness of ammonia excretion through active NH4+ transport, manipulation of ambient pH, or reduction in ammonia permeability through the branchial and cutaneous epithelia. Recent reports on ammonia toxicity in mammalian brain reveal the importance of permeation of ammonia through the blood-brain barrier and passages of ammonia and water through transporters in the plasmalemma of brain cells. Additionally, brain ammonia toxicity could be related to the passage of glutamine through the mitochondrial membranes into the mitochondrial matrix. On the other hand, recent reports on ammonia excretion in fish confirm the involvement of Rhesus glycoproteins in the branchial and cutaneous epithelia. Therefore, this review focuses on both the earlier literature and the up-to-date information on the problems and mechanisms concerning the permeation of ammonia, as NH3, NH4+ or proton-neutral nitrogenous compounds, across mitochondrial membranes, the blood-brain barrier, the plasmalemma of neurons, and the branchial and cutaneous epithelia of fish. It also addresses how certain fishes with high ammonia tolerance defend against ammonia toxicity through the regulation of the permeation of ammonia and related nitrogenous compounds through various types of membranes. It is hoped that this review would revive the interests in investigations on the passage of ammonia through the mitochondrial membranes and the blood-brain barrier of ammonotelic fishes and fishes with high brain ammonia-tolerance, respectively.

Fish-friendly future

International Nuclear Information System (INIS)

Brookshier, P.; Newman, Gemma

2001-01-01

The latest US research into ways of reducing the harm to fish from hydroelectric turbines is outlined. Laboratory studies, field studies and advanced computational studies are being carried out to improve the understanding of and reduce the effects of stress and injury to fish from turbines. The Advanced Hydro Turbine System programme is part of the Department of Energy's Hydropower Programme. Turbine passage injuries are caused by a number of mechanisms, leaving the fish either dead or stunned. Advanced turbine technology can help to minimise fish injury and can add dissolved oxygen to the discharged water, thus improving water quality. Turbine modifications are aimed at all species, but studies have focussed on salmon, trout and eels. The new minimum gap runner (MGR) appear as efficient as standard Kaplan turbines

Assessment of whether upstream passage for Lake Sturgeon is needed at the Pointe du Bois Generating Station (Winnipeg River)

International Nuclear Information System (INIS)

Pratt, T.

2010-01-01

This document reviewed Manitoba Hydro's proposal to modernize the Pointe du Bois Generating Station (GS) on the Winnipeg River, with particular reference to the potential impacts on Lake Sturgeon in Management Unit 5 (MU5) where large numbers of the fish spawn at the base of the falls. The modernization will involve replacing the spillway, dam segments and replacing or repairing the powerhouse. The pros and cons of providing upstream fish passage for Lake Sturgeon and the generating station were outlined. The only spawning area in the MU5 area may be altered considerably due to changes in water flow, depending on the design chosen for modernization. A potential benefit of providing upstream fish passage for Lake Sturgeon would be to increase genetic diversity within the Winnipeg River. Another potential benefit would be to allow Lake Sturgeon, from the relatively dense population below the GS, to move upstream into MU4 where unfilled habitat may be available and Lake Sturgeon abundance is lower. A potential disadvantage of providing fish passage would be the loss of individual Lake Sturgeon from the healthy population in MU5 with no accompanying benefit to MU4. There would be no net gain to MU4 or MU5 if migrating Lake Sturgeon returned to MU5 rather than proceeding upstream. It was concluded that these current gaps in knowledge must be filled in order to fully assess the environmental impacts. 2 figs.

Development of a more fish-tolerant turbine runner, advanced hydropower turbine project

International Nuclear Information System (INIS)

Cook, T.C.; Hecker, G.E.

1997-02-01

Alden Research Laboratory, Inc. (ARL) and Northern Research and Engineering Corporation (NREC) conducted a research program to develop a turbine runner which will minimize fish injury and mortality at hydroelectric projects. ARL?NREC have developed a runner shape which minimizes the number of blade leading edges, reduces the pressure versus time and the velocity versus distance gradients within the runner, minimizes or eliminates the clearance between the runner and runner housing, and maximizes the size of the flow passages, all with minimal penalty on turbine efficiency. An existing pump impeller provided the starting point for developing the fish tolerant turbine runner. The Hidrostal pump is a single bladed combined screw/centrifugal pump which has been proven to transport fish with minimal injury. The focus of the ARL/NREC research project was to develop a new runner geometry which is effective in downstream fish passage and hydroelectric power generation. A flow of 1,000 cfs and a head in the range of 75 ft to 100 ft were selected for conceptual design of the new runner. Conceptual design of the new runner began with a re-evaluation of studies which have been previously conducted to identify probable sources of injury to fish passing through hydraulic turbines. Criteria relative to hydraulic characteristics which are favorable for fish passage were prepared based on a reassessment of the available information. Important criteria used to develop the new runner design included low pressure change rates, minimum absolute pressures, and minimum shear. Other criteria which are reflected in the runner design are a minimum number of blades (only two), minimum total length of leading edges, and large flow passages. 86 figs., 5 tabs

Hydroacoustic Evaluation of Juvenile Salmonid Passage at The Dalles Dam in 2004

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Hanks, Michael E.; Khan, Fenton; Cook, Chris B.; Hedgepeth, J; Mueller, Robert P.; Rakowski, Cynthia L.; Richmond, Marshall C.; Sargeant, Susan L.; Serkowski, John A.; Skalski, John R.

2005-06-01

The U.S. Army Corps of Engineers Portland District engaged the Pacific Northwest National Laboratory to evaluate juvenile salmon passage at The Dalles Dam in 2004 to inform decisions about long-term measures and operations to enhance sluiceway and spill passage and reduce turbine passage to improve smolt survival at the dam. PNNL used fixed-location hydroacoustic sampling across the entire project, especially at the sluiceway and spillway, using multiple split-beam transducers at selected locations. At the sluiceway nearfield, we used an acoustic camera to track fish. The fish data were interpreted and integrated with hydraulic data from a CFD model and in-field ADCP measurements. Two sluiceway operations were compared: West only (SL 1) vs. West+East (SL 1 + SL 18). Based on our findings, we concluded that The Dalles Dam sluiceway has the potential to be highly efficient and effective at passing juvenile salmonids. This potential could be tapped with hydraulic and entrance enhancements to the sluiceway. We recommended the following: (1) six rather than three sluice gates should be opened to take advantage of the maximum hydraulic capacity of the sluiceway. (2) The turbine units below open sluice gates should be operated as a standard fish operations procedure. (3) In 2005, the Corps and fisheries agencies should consider operating sluice gates in one or more of the following combinations of six gates: (a) SL 1-1, 1-2, 1-3 and SL 18-1, 18-2, 18-3 (repeat 2004 operation), (b) SL 1-1, 1-2, 1-3 and SL 11-1, 11-2, 11-3, or (c) SL 1-1, 1-2, 1-3 and SL 2-1, 2-2, 2-3. The following elements for surface flow bypasses which should be considered during design of any sluiceway enhancements at The Dalles Dam: (1) form an extensive surface flow bypass flow net (surface bypass discharge greater than {approx}7% of total project discharge), (2) create a gradual increase in water velocity approaching the surface flow bypass (ideally, acceleration < 1 m/s/m), (3) make water

Fish entrainment and mortality at the French Landing Hydroelectric Powerhouse

International Nuclear Information System (INIS)

Sundquist, M.J.

1991-01-01

This paper is a case study which explains the fish mortality study performed and results obtained at an existing hydroelectric powerhouse in Michigan. Undertaken in 1989 and 1990, this study provides data for determining effects of turbine passage on area fish

Compliance Monitoring of Yearling and Subyearling Chinook Salmon and Juvenile Steelhead Survival and Passage at John Day Dam, 2012

Energy Technology Data Exchange (ETDEWEB)

Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Weiland, Mark A.; Woodley, Christa M.; Hughes, James S.; Ploskey, Gene R.; Deng, Zhiqun; Carlson, Thomas J.

2013-05-01

The purpose of this compliance study was to estimate dam passage survival of yearling and subyearling Chinook salmon and steelhead smolts at John Day Dam during the spring and summer outmigrations in 2012. Under the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp), dam passage survival should be greater than or equal to 0.96 for spring migrants and greater than or equal to 0.93 for summer migrants, estimated with a standard error (SE) less than or equal to 0.015. The study also estimated smolt passage survival from the forebay 2 km upstream of the dam to the tailrace 3 km downstream of the dam, as well as the forebay residence time, tailrace egress time, spill passage efficiency (SPE), and fish passage efficiency (FPE), as required in the Columbia Basin Fish Accords (Fish Accords). A virtual/paired-release design was used to estimate dam passage survival at John Day Dam. The approach included releases of smolts, tagged with acoustic micro-transmitters, above John Day Dam that contributed to the formation of a virtual release at the face of John Day Dam. A survival estimate from this release was adjusted by a paired release below John Day Dam. A total of 3376 yearling Chinook salmon, 5726 subyearling Chinook salmon, and 3239 steelhead smolts were used in the virtual releases. Sample sizes for the below-dam paired releases (R2 and R3, respectively) were 997 and 995 for yearling Chinook salmon smolts, 986 and 983 for subyearling Chinook salmon smolts, and 1000 and 1000 for steelhead smolts. The Juvenile Salmon Acoustic Telemetry System (JSATS) tags were manufactured by Advanced Telemetry Systems. Model SS300 tags, weighing 0.304 g in air, were surgically implanted in yearling and subyearling Chinook salmon, and Model SS130 tag, weighing 0.438 g in air, were surgically implanted in juvenile steelhead for this investigation. The intent of the spring study was to estimate dam passage survival during both 30% and 40% spill conditions. The two

Does boat traffic cause displacement of fish in estuaries?

Science.gov (United States)

Becker, Alistair; Whitfield, Alan K; Cowley, Paul D; Järnegren, Johanna; Næsje, Tor F

2013-10-15

Estuaries are increasingly under threat from a variety of human impacts. Recreational and commercial boat traffic in urban areas may represent a significant disturbance to fish populations and have particularly adverse effects in spatially restricted systems such as estuaries. We examined the effects of passing boats on the abundance of different sized fish within the main navigation channel of an estuary using high resolution sonar (DIDSON). Both the smallest (100-300 mm) and largest (>501 mm) size classes had no change in their abundance following the passage of boats. However, a decrease in abundance of mid-sized fish (301-500 mm) occurred following the passage of boats. This displacement may be attributed to a number of factors including noise, bubbles and the rapidly approaching object of the boat itself. In highly urbanised estuarine systems, regular displacement by boat traffic has the potential to have major negative population level effects on fish assemblages. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fish monitoring project -- Oregon: Smolt monitoring activities at Little Goose Dam in 1996. Annual Report 1996

International Nuclear Information System (INIS)

Setter, A.

1998-01-01

The juvenile fish facility at Little Goose Dam is operated seasonally to collect and bypass downstream migrating smolts and keep them from passing through the turbine blades. Fish are diverted from turbines by traveling screens as they sound in the forebay to pass the dam. A small percentage of the passing fish are sampled on a daily basis to provide information on fish condition, species composition, migration timing, and size distribution. Oregon Department of Fish and Wildlife personnel perform daily fish sampling and data collection. Physical operation of the facility is the responsibility of the US Army Corps of Engineers. Data is reported to the Fish Passage Center daily by means of electronic data transfer. Funding for this project was provided through the Smolt Monitoring Program administered by the Fish Passage Center. Overall, the number of fish collected and sampled in 1996 was a reduction from the previous years of operation. The 1996 migration season was characterized by higher than average flows and greater spill frequency at the dam. It was the first year that coho salmon were obtained in the sample. The predominant species collected was steelhead with hatchery fish outnumbering wild fish by a ratio of 8:1. An increased emphasis was placed on gas bubble trauma examination and a routine, consistent effort was implemented using a protocol established by the Fish Passage Center. The objective of the gas bubble trauma (GBT) examinations was to document the relative incidence of symptoms throughout the migration season

Non-linearity of the response accommodative convergence to accommodation ratio.

Science.gov (United States)

Johnston, Miriam S; Firth, Alison Y

2013-09-01

Previous studies have reported variation in stimulus accommodative convergence to accommodation (AC/A) ratio across differing accommodative stimuli. Response AC/A ratio was assessed across 4 accommodative demands to determine if these differences could be due to accommodative inaccuracies to stimuli. Twenty-three student participants aged 18 to 26 years (mean age 20.3 ± 1.7 years) successfully completed all testing conditions. The modified Thorington technique was used at 4 m to measure heterophoria. The Shin Nippon SRW 5000 infrared autorefractor was used to determine accommodative change to -1.50, -3.00, -4.50, and -6.00D lens stimuli. Significant differences were found in response AC/A ratio between different minus lens stimulated accommodative demands (p accommodative stimuli, but tended to increase with accommodative demand. Significant variability in response AC/A ratio was found, both within individuals to different accommodative demands, and between individuals across the data set.

Effects of barge traffic on distribution and survival of ichthyoplankton and small fishes in the upper Mississippi River

Science.gov (United States)

Holland, L.E.

1986-01-01

Short-term impacts of commercial barge traffic on fish eggs, larvae, young-of-the-year (age-0) fishes, and small adults in the main channel of the upper Mississippi River were examined. Barge passages caused significant changes in the distribution of eggs and larvae in the study area. The mean catch of ichthyoplankton was reduced in both surface and bottom waters for 90 min after passage of vessels downstream. The effects of upstream traffic on catch ranged from nil in surface or bottom samples to short-term increases in surface samples immediately after passage. No consistent effect on the catch of age-0 or small adult fishes in surface or bottom trawls was evident.

Frankenmuth Dam Fish Passage, Cass River, Saginaw County, Michigan

Science.gov (United States)

2012-11-01

2009letter, our office and the Alpena Fish and Wildlife Conservation Office have been worldng with you to develop monitoring programs to assess changes...Sargent. MDNR. Wildlife Division. Lansing, MI Andrea Ania, USFWS, Alpena , M1 EA - C-7 ZIIBIWING CENTER ot A~t.:..~ c •. lt • .,..~ 1’¥- ,..1

Pathways of Barotrauma in Juvenile Salmonids Exposed to Simulated Hydroturbine Passage: Boyle’s Law vs. Henry’s Law

Energy Technology Data Exchange (ETDEWEB)

Brown, Richard S.; Pflugrath, Brett D.; Colotelo, Alison HA; Brauner, Colin J.; Carlson, Thomas J.; Deng, Zhiqun; Seaburg, Adam

2012-06-01

On their seaward migration, juvenile salmonids commonly pass hydroelectric dams. Fish passing by the turbine blade may experience rapid decompression, the severity of which can be highly variable and may result in a number of barotraumas. The mechanisms of these injuries can be due to expansion of existing bubbles or gases coming out of solution; governed by Boyle’s Law and Henry’s Law, respectively. This paper combines re-analysis of published data with new experiments to gain a better understanding of the mechanisms of injury and mortality for fish experiencing rapid decompression associated with hydroturbine passage. From these data it appears that the majority of decompression related injuries are due to the expansion of existing bubbles in the fish, particularly the expansion and rupture of the swim bladder. This information is particularly useful for fisheries managers and turbine manufacturers, demonstrating that reducing the rate of swim bladder ruptures by reducing the frequency of occurrence and severity of rapid decompression during hydroturbine passage could reduce the rates of injury and mortality for hydroturbine passed juvenile salmonids.

Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish

Energy Technology Data Exchange (ETDEWEB)

Neitzel, Duane A.

2009-09-14

Migratory and resident fish in the Columbia River Basin are exposed to stresses associated with hydroelectric power production, including changes in pressure as they pass through turbines and dissolved gas supersaturation (resulting from the release of water from the spillway). To examine pressure changes as a source of turbine-passage injury and mortality, Pacific Northwest National Laboratory scientists conducted specific tests using a hyperbaric chamber. Tests were designed to simulate Kaplan turbine passage conditions and to quantify the response of fish to rapid pressure changes, with and without the complication of fish being acclimated to gas-supersaturated water.

Monitoring of Juvenile Yearling Chinook Salmon and Steelhead Survival and Passage at John Day Dam, Spring 2010

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A.; Ploskey, Gene R.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Skalski, J. R.; Townsend, Richard L.

2012-11-15

The purpose of this study was to compare dam passage survival, at two spill treatment levels, of yearling Chinook salmon and steelhead smolts at John Day Dam during spring 2010. The two treatments were 30% and 40% spill out of total project discharge. Under the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp), dam passage survival should be greater than or equal to 0.96 and estimated with a standard error (SE) less than or equal 0.015. The study also estimated forebay residence time, tailrace egress time, and spill passage efficiency (SPE), as required in the Columbia Basin Fish Accords. However, by agreement among the stakeholders, this study was not an official BiOp compliance test because the long-term passage measures at John Day Dam have yet to be finalized and another year of spill-treatment testing was desired.

Effects of passage barriers on demographics and stability properties of a virtual trout populations

Science.gov (United States)

Bret Harvey; Steven Railsback

2011-01-01

Habitat fragmentation is widely assumed to have negative effects on populations and communities, but some effects of fragmentation are subtle, difficult to measure and not always negative. For stream fish, barriers to upstream passage, such as waterfalls or culverts with perched outlets, are a common cause of fragmentation. We explored the effects of barriers on a...

Survival and Passage of Yearling Chinook Salmon and Steelhead at The Dalles Dam, Spring 2011 - FINAL REPORT

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Hennen, Matthew J.; Zimmerman, Shon A.; Batten, G.; Carpenter, Scott M.; Deng, Zhiqun; Fu, Tao; Hughes, James S.; Martinez, Jayson J.; Ploskey, Gene R.; Royer, Ida M.; Townsend, Richard L.; Woodley, Christa M.; Kim, Jeongkwon; Etherington, D. J.; Skalski, J. R.; Carlson, Thomas J.; Cushing, Aaron W.; Fisher, Erik J.; Greiner, Michael J.; Khan, Fenton; Mitchell, T. D.; Rayamajhi, Bishes; Seaburg, Adam; Weiland, Mark A.

2012-10-01

The study reported herein was conducted by the Pacific Northwest National Laboratory (PNNL) and the University of Washington (UW) for the U.S. Army Corps of Engineers, Portland District (USACE). The PNNL and UW project managers were Drs. Thomas J. Carlson and John R. Skalski, respectively. The USACE technical lead was Mr. Brad Eppard. The study was designed to estimate dam passage survival and other performance measures at The Dalles Dam as stipulated by the 2008 Federal Columbia River Power System Biological Opinion (BiOp) and the 2008 Columbia Basin Fish Accords. The study is being documented in two types of reports: compliance and technical. A compliance report is delivered within 6 months of the completion of the field season and focuses on results of the performance metrics outlined in the 2008 BiOp and Fish Accords. A technical report is produced within the 18 months after field work, providing comprehensive documentation of a given study and results on route-specific survival estimates and fish passage distributions, which are not included in compliance reports. This technical report concerns the 2011 acoustic telemetry study at The Dalles Dam.

Approach, passage, and survival of juvenile salmonids at Little Goose Dam, Washington: Post-construction evaluation of a temporary spillway weir, 2009

Science.gov (United States)

Beeman, J.W.; Braatz, A.C.; Hansel, H.C.; Fielding, S.D.; Haner, P.V.; Hansen, G.S.; Shurtleff, D.J.; Sprando, J.M.; Rondorf, D.W.

2010-01-01

This report describes a study of dam passage and survival of radio-tagged juvenile salmonids after installation of a temporary spillway weir (TSW) at Little Goose Dam, Washington, in 2009. The purpose of the study was to document fish passage and survival when the dam was operated with the TSW in place. Spillway weirs are one of several methods used to improve downstream passage of juvenile salmonids. Each spillway weir design is based on the concept of providing an overflow weir with a depth more similar to the natural migration depth of juvenile salmonids than conventional spill bays. Little Goose Dam was the last of the four lower Snake River dams to have a spillway weir installed. This was the first year that some form of surface passage device was operating at all Snake River and Columbia River dams between Lewiston, Idaho, and the Columbia River estuary. The study design stipulated that a total of 30 percent of the river discharge would continuously be passed over the TSW and the conventional spill bays, and this percentage was achieved. The TSW also was to be operated at the 'low crest' elevation during the spring and the 'high crest' elevation during the summer, but the TSW was only operated at the low crest elevation during this study. Behavior, passage, and survival of spring and summer juvenile salmonid migrants passing through Little Goose Dam were examined using radio telemetry. Survival was estimated using the Route Specific Survival Model (RSSM) by releasing tagged fish near Central Ferry State Park 21 kilometers upstream of the dam and in the tailrace approximately 0.5 kilometer downstream of the dam. From April 18 to May 21, 2009, 1,520 yearling Chinook salmon (Oncorhynchus tshawytscha) and 1,517 juvenile steelhead (O. mykiss) were radio tagged and released. From June 6 to July 5, 2009, 4,251 subyearling Chinook salmon (O. tshawytscha) were radio tagged and released. Release dates of subyearling Chinook salmon were selected to avoid 'reservoir

Invasive zebra mussels (Driessena polymorpha) and Asian clams (Corbicula fluminea) survive gut passage of migratory fish species: implications for dispersal

Science.gov (United States)

Gatlin, Michael R.; Shoup, Daniel E.; Long, James M.

2013-01-01

The introduction and spread of invasive species is of great concern to natural resource managers in the United States. To effectively control the spread of these species, managers must be aware of the multitude of dispersal methods used by the organisms. We investigated the potential for survival through the gut of a migrating fish (blue catfish, Ictalurus furcatus) as a dispersal mechanism for two invasive bivalves: zebra mussel (Driessena polymorpha) and Asian clam (Corbicula fluminea). Blue catfish (N = 62) were sampled over several months from Sooner Lake, Oklahoma, transported to a laboratory and held in individual tanks for 48 h. All fecal material was collected and inspected for live mussels. Survival was significantly related to water temperature in the lake at the time of collection, with no mussels surviving above 21.1 C°, whereas 12 % of zebra mussels (N = 939) and 39 % of Asian clams (N = 408) consumed in cooler water survived gut passage. This research demonstrates the potential for blue catfish to serve as a dispersal vector for invasive bivalves at low water temperatures.

Acoustic Telemetry Evaluation of Juvenile Salmonid Passage and Survival Proportions at John Day Dam, 2009

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A.; Ploskey, Gene R.; Hughes, James S.; Deng, Zhiqun; Fu, Tao; Kim, Jin A.; Johnson, Gary E.; Fischer, Eric S.; Khan, Fenton; Zimmerman, Shon A.; Faber, Derrek M.; Carter, Kathleen M.; Boyd, James W.; Townsend, Richard L.; Skalski, J. R.; Monter, Tyrell J.; Cushing, Aaron W.; Wilberding, Matthew C.; Meyer, Matthew M.

2011-09-28

The overall purpose of the acoustic telemetry study at JDA during 2009 was to determine the best configuration and operation for JDA prior to conducting BiOp performance standard tests. The primary objective was to determine the best operation between 30% and 40% spill treatments. Route-specific and JDA to TDA forebay survival estimates, passage distribution, and timing/behavior metrics were used for comparison of 30% to a 40% spill treatments. A secondary objective was to evaluate the performance of TSWs installed in spill bays 15 and 16 and to estimate fish survival rates and passage efficiencies under 30% and 40% spill-discharge treatments each season.

Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish

International Nuclear Information System (INIS)

Abernethy, Cary S; Amidan, Brett G

2001-01-01

The objective of this study was to examine the relative importance of pressure changes as a source of turbine-passage injury and mortality. Specific tests were designed to quantify the response of fish to rapid pressure changes typical of turbine passage, with and without the complication of the fish being acclimated to gas supersaturated water. We investigated the responses of rainbow trout (Oncorhynchus mykiss), chinook salmon (O. tshawytscha), and bluegill sunfish (Lepomis macrochirus) to these two stresses, both singly and in combination

Functional testing of a fish sluice, Buchholz small hydro plant - Final report; Funktionskontrolle Fischschleuse, KWKW Buchholz - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Ruhle, Ch. [Buero fuer Jagd- und Fischereifragen, Schmerikon (Switzerland); Scherrer, I. [Entegra Wasserkraft AG, St. Gallen (Switzerland)

2009-01-15

Since more than 100 years the diversion hydropower plant of Buchholz at the river Glatt (canton Saint Gall) has been out of operation. With its reactivation as run-of-river scheme, the river meadow, originated due to sedimentation in the former storage basin, with its beaver habitat, could be preserved. For the first time in Switzerland, a fish lock was implemented for the upstream passage way for fish. The fish lock was built directly into for stability reasons newly constructed secondary concrete at the downstream side of the old dam. At the upper lock opening a weir basked is installed, where the migrating fish are recorded. The examination proofed that the fish lock in principle is working for strong swimming fish species (qualitative proof of the performance control). In case of flood caused drift, the migrating fish seem to accept the fish passage. The attempt to quantify the proportion of the migrating willing fish which actually swim through the lock (quantitative proof of the performance control) did not produce satisfactory results. (authors)

Monitoring of Juvenile Subyearling Chinook Salmon Survival and Passage at John Day Dam, Summer 2010

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A.; Ploskey, Gene R.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Skalski, J. R.; Townsend, Richard L.

2012-11-15

The purpose of this study was to evaluate dam passage survival of subyearling Chinook salmon (Oncorhynchus tshawytscha; CH0) at John Day Dam (JDA) during summer 2010. This study was conducted by researchers from the Pacific Northwest National Laboratory (PNNL) in collaboration with the Pacific States Marine Fisheries Commission (PSMFC) and the University of Washington (UW). The study was designed to estimate the effects of 30% and 40% spill treatment levels on single release survival rates of CH0 passing through two reaches: (1) the dam, and 40 km of tailwater, (2) the forebay, dam, and 40 km of tailwater. The study also estimated additional passage performance measures which are stipulated in the Columbia Basin Fish Accords.

Reconnecting fragmented sturgeon populations in North American rivers

Science.gov (United States)

Jager, Henriette; Parsley, Michael J.; Cech, Joseph J. Jr.; McLaughlin, R.L.; Forsythe, Patrick S.; Elliott, Robert S.

2016-01-01

The majority of large North American rivers are fragmented by dams that interrupt migrations of wide-ranging fishes like sturgeons. Reconnecting habitat is viewed as an important means of protecting sturgeon species in U.S. rivers because these species have lost between 5% and 60% of their historical ranges. Unfortunately, facilities designed to pass other fishes have rarely worked well for sturgeons. The most successful passage facilities were sized appropriately for sturgeons and accommodated bottom-oriented species. For upstream passage, facilities with large entrances, full-depth guidance systems, large lifts, or wide fishways without obstructions or tight turns worked well. However, facilitating upstream migration is only half the battle. Broader recovery for linked sturgeon populations requires safe “round-trip” passage involving multiple dams. The most successful downstream passage facilities included nature-like fishways, large canal bypasses, and bottom-draw sluice gates. We outline an adaptive approach to implementing passage that begins with temporary programs and structures and monitors success both at the scale of individual fish at individual dams and the scale of metapopulations in a river basin. The challenge will be to learn from past efforts and reconnect North American sturgeon populations in a way that promotes range expansion and facilitates population recovery.

Effect of Multiple Turbine Passage on Juvenile Snake River Salmonid Survival

International Nuclear Information System (INIS)

Ham, Kenneth D.; Anderson, James J.; Vucelick, Jessica A.

2005-01-01

This report describes a study conducted by Pacific Northwest National Laboratory to identify populations of migrating juvenile salmonids with a potential to be impacted by repeated exposure to turbine passage conditions. This study is part of a research program supported by the U.S. Department of Energy Wind/Hydropower Program. The program's goal is to increase hydropower generation and capacity while enhancing environmental performance. Our study objective is to determine whether the incremental effects of turbine passage during downstream migration impact populations of salmonids. When such a potential is found to exist, a secondary objective is to determine what level of effect of passing multiple turbines is required to decrease the number of successful migrants by 10%. This information will help identify whether future laboratory or field studies are feasible and design those studies to address conditions that present the greatest potential to improve dam survival and thus benefit fish and power generation

Can current models of accommodation and vergence predict accommodative behavior in myopic children?

Science.gov (United States)

Sreenivasan, Vidhyapriya; Irving, Elizabeth L; Bobier, William R

2014-08-01

Investigations into the progression of myopia in children have long considered the role of accommodation as a cause and solution. Myopic children show high levels of accommodative adaptation, coupled with accommodative lag and high response AC/A (accommodative convergence per diopter of accommodation). This pattern differs from that predicted by current models of interaction between accommodation and vergence, where weakened reflex responses and a high AC/A would be associated with a low not high levels of accommodative adaptation. However, studies of young myopes were limited to only part of the accommodative vergence synkinesis and the reciprocal components of vergence adaptation and convergence accommodation were not studied in tandem. Accordingly, we test the hypothesis that the accommodative behavior of myopic children is not predicted by current models and whether that departure is explained by differences in the accommodative plant of the myopic child. Responses to incongruent stimuli (-2D, +2D adds, 10 prism diopter base-out prism) were investigated in 28 myopic and 25 non-myopic children aged 7-15 years. Subjects were divided into phoria groups - exo, ortho and eso based upon their near phoria. The school aged myopes showed high levels of accommodative adaptation but with reduced accommodation and high AC/A. This pattern is not explained by current adult models and could reflect a sluggish gain of the accommodative plant (ciliary muscle and lens), changes in near triad innervation or both. Further, vergence adaptation showed a predictable reciprocal relationship with the high accommodative adaptation, suggesting that departures from adult models were limited to accommodation not vergence behavior. Copyright © 2014 Elsevier Ltd. All rights reserved.

Compliance Monitoring of Juvenile Yearling Chinook Salmon and Steelhead Survival and Passage at The Dalles Dam, Spring 2011

Energy Technology Data Exchange (ETDEWEB)

Skalski, John R.; Townsend, Richard L.; Seaburg, Adam; Johnson, Gary E.; Ploskey, Gene R.; Carlson, Thomas J.

2012-06-12

The study estimated dam passage survival at The Dalles Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and provided additional performance measures as stipulated in the Columbia Basin Fish Accords. This summary report focuses on spring run stocks, yearling Chinook salmon and steelhead.

Compliance Monitoring of Juvenile Yearling Chinook Salmon and Steelhead Survival and Passage at The Dales Dam, Spring 2011

Energy Technology Data Exchange (ETDEWEB)

Skalski, John R.; Townsend, Richard L.; Seaburg, Adam; Johnson, Gary E.; Ploskey, Gene R.; Carlson, Thomas J.

2012-02-01

The study estimated dam passage survival at The Dalles Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and provided additional performance measures as stipulated in the Columbia Basin Fish Accords. This summary report focuses on spring run stocks, yearling Chinook salmon and steelhead.

Lake Roosevelt Rainbow Trout : Habitat/Passage Improvement Project Annual Report 2000.

Energy Technology Data Exchange (ETDEWEB)

Sear, Sheri

2001-02-01

Lake Franklin D. Roosevelt was created with the completion of the Grand Coulee Dam in 1942. The lake stretches 151 miles up-stream to the International border between the United States and Canada at the 49th parallel. Increased recreational use, subsistence and sport fishing has resulted in intense interest and possible exploitation of the resources within the lake. Previous studies of the lake and its fishery have been limited. Early studies indicate that natural reproduction within the lake and tributaries are not sufficient to support a rainbow trout (Onchoryhnchus mykiss) fishery (Scholz et. al., 1988). These studies indicate that the rainbow trout population may be limited by lack of suitable habitat for spawning and rearing (Scholz et. al., 1988). The initial phase of this project (Phase I, baseline data collection- 1990-91) was directed at the assessment of limiting factors such as quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other limiting factors. Population estimates were conducted using the Seber/LeCren removal/depletion method. After the initial assessment of stream parameters, several streams were selected for habitat/passage improvement projects (Phase II, implementation-1992-96). At the completion of project habitat improvements, the final phase (Phase III, monitoring) began. This phase will assess changes and gauge the success achieved through the improvements. The objective of the project is to correct passage barriers and improve habitat conditions of selected tributaries to Lake Roosevelt for adfluvial rainbow trout that utilize tributary streams for spawning and rearing. Streams with restorable habitats were selected for improvements. Completion of improvement efforts should increase the adfluvial rainbow trout contribution to the resident fishery in Lake Roosevelt. Three co-operating agencies, the Confederated Tribes of the Colville Reservation (CCT), the Spokane Tribe of Indians (STI

Lake Roosevelt Rainbow Trout : Habitat/Passage Improvement Project Annual Report 1999.

Energy Technology Data Exchange (ETDEWEB)

Jones, Charles D.

2000-02-01

Lake Franklin D. Roosevelt was created with the completion of the Grand Coulee Dam in 1942. The lake stretches 151 miles up-stream to the International border between the United States and Canada at the 49th parallel. Increased recreational use, subsistence and sport fishing has resulted in intense interest and possible exploitation of the resources within the lake. Previous studies of the lake and its fishery have been limited. Early studies indicate that natural reproduction within the lake and tributaries are not sufficient to support a rainbow trout (Onchoryhnchus mykiss) fishery (Scholz et. al., 1988). These studies indicate that the rainbow trout population may be limited by lack of suitable habitat for spawning and rearing (Scholz et. al., 1988). The initial phase of this project (Phase I, baseline data collection- 1990-91) was directed at the assessment of limiting factors such as quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other limiting factors. Population estimates were conducted using the Seber/LeCren removal/depletion method. After the initial assessment of stream parameters, several streams were selected for habitat/passage improvement projects (Phase II, implementation-1992-96). At the completion of project habitat improvements, the final phase (Phase III, monitoring) began. This phase will assess changes and gauge the success achieved through the improvements. The objective of the project is to correct passage barriers and improve habitat conditions of selected tributaries to Lake Roosevelt for adfluvial rainbow trout that utilize tributary streams for spawning and rearing. Streams with restorable habitats were selected for improvements. Completion of improvement efforts should increase the adfluvial rainbow trout contribution to the resident fishery in Lake Roosevelt. Three co-operating agencies, the Confederated Tribes of the Colville Reservation (CCT), the Spokane Tribe of Indians (STI

Fish dispersal in a seasonal wetland: influence of anthropogenic structures

Czech Academy of Sciences Publication Activity Database

Hohausová, Eva; Lavoy, R. J.; Allen, M. S.

2010-01-01

Roč. 61, č. 6 (2010), s. 682-694 ISSN 1323-1650. [Behaviour and Ecology of Freshwater Fish. Silkeborg, 22.08.2004-26.08.2004] Grant - others:GA MŠk(CZ) ME 659 Institutional research plan: CEZ:AV0Z60170517 Keywords : fish dispersal speed * sedentary and non-migratory species * minimum passage depth * freshwater marsh Subject RIV: EH - Ecology, Behaviour Impact factor: 1.572, year: 2010

Fish ladder of Lajeado Dam: migrations on one-way routes?

Directory of Open Access Journals (Sweden)

Angelo Antônio Agostinho

Full Text Available Fish ladders are generally conceived to reestablish connectivity among critical habitats for migratory species, thus mitigating the impacts of the blockage of migration routes by dams. If this management tool is to be meaningful for conserving fish species, it must provide a fully permeable connection and assure both upward and downward movements. However, because reservoirs have very different hydrodynamics than the original river, it is expected that, at least in the inner area, they may constitute an additional barrier to this movement, especially for descending fish. Thus, the present study sought to determine if migratory fish and their offspring disperse downstream from the dam after ascending a ladder and spawning in the upper reaches of a basin. To achieve this purpose, we evaluated the limitation imposed by lentic areas to the descent of eggs, larvae and adults of migratory species; we also determined the abundance and composition of larvae present in the plankton near the dam, and compared the intensity of the upward and downward movements of adult fish. Samples of ichthyoplankton were taken upriver, inside the reservoir, in the river downstream from the dam, and in the forebay of the Lajeado Dam on the Tocantins River (Luis Eduardo Magalhães Hydroelectric Plant, from October, 1999 through September, 2004. The densities of fish ascending and descending the ladder were determined experimentally on eight occasions, from June, 2004 to March, 2005. Due to difficulties in identifying the true fish origin (up or down in the environments connected by the fish passage system, the evaluation of the distribution of migratory fish in reservoirs was based on the landings of the commercial fishery conducted along the Itaipu Reservoir during the four years preceding (2001 through 2003 the construction of the lateral channel (fish-passage mechanism. Fish eggs and larvae drifting down the Tocantins River did not appear in samples taken in the lower

The Influence of Tag Presence on the Mortality of Juvenile Chinook Salmon Exposed to Simulated Hydroturbine Passage: Implications for Survival Estimates and Management of Hydroelectric Facilities

Energy Technology Data Exchange (ETDEWEB)

Carlson, Thomas J.; Brown, Richard S.; Stephenson, John R.; Pflugrath, Brett D.; Colotelo, Alison HA; Gingerich, Andrew J.; Benjamin, Piper L.; Langeslay, Mike; Ahmann, Martin L.; Johnson, Robert L.; Skalski, John R.; Seaburg, Adam; Townsend, Richard L.

2012-05-01

Each year, millions of fish have telemetry tags (acoustic, radio, inductive) surgically implanted to assess their passage and survival through hydropower facilities. One route of passage of particular concern is through hydro turbines, in which fish may be exposed to a range of potential injuries, including barotraumas from rapid decompression. The change in pressure from acclimation to exposure (nadir) has been found to be an important factor in predicting the likelihood of mortality and injury for juvenile Chinook salmon undergoing rapid decompression associated with simulated turbine passage. The presence of telemetry tags has also been shown to influence the likelihood of injury and mortality for juvenile Chinook salmon. This research investigated the likelihood of mortality and injury for juvenile Chinook salmon carrying telemetry tags and exposed to a range of simulated turbine passage. Several factors were examined as predictors of mortal injury for fish undergoing rapid decompression, and the ratio of pressure change and tag burden were determined to be the most predictive factors. As the ratio of pressure change and tag burden increase, the likelihood of mortal injury also increases. The results of this study suggest that previous survival estimates of juvenile Chinook salmon passing through hydro turbines may have been biased due to the presence of telemetry tags, and this has direct implications to the management of hydroelectric facilities. Realistic examples indicate how the bias in turbine passage survival estimates could be 20% or higher, depending on the mass of the implanted tags and the ratio of acclimation to exposure pressures. Bias would increase as the tag burden and pressure ratio increase, and have direct implications on survival estimates. It is recommended that future survival studies use the smallest telemetry tags possible to minimize the potential bias that may be associated with carrying the tag.

Characterizing the Fish Passage Environment at The Dalles Dam Spillway: 2001-2004

Energy Technology Data Exchange (ETDEWEB)

Richmond, Marshall C.; Carlson, Thomas J.; Serkowski, John A.; Cook, Chris B.; Duncan, Joanne P.; Perkins, William A.

2007-10-10

The spill environment at The Dalles Dam in 2001-2004 was characterized using a field-deployed autonomous sensor (the so-called Sensor Fish), computational fluid dynamics (CFD) modeling, and Lagrangian particle tracking. The sensor fish has a self-contained capability to digitally the record pressure and triaxial accelerations it was exposed to following its release into the spillway. After recovery downstream of the tailrace, the data stored in the memory of the sensor are downloaded and stored for analysis. The spillway, stilling basin, and tailrace hydrodynamics were simulated using an unsteady, free-surface, three-dimensional CFD code that solved the Reynolds-averaged Navier-Stokes equations in conjunction with a two-equation turbulence model. The results from the CFD simulations were then used in a Lagrangian particle tracking model that included the effects of mass, drag, and buoyancy in the particle equation of motion. A random walk method was used to simulate the effects of small-scale turbulence on the particle motion. Several operational and structural conditions were evaluated using the Sensor Fish, CFD, and particle tracking. Quantifying events such as strike and stilling basin retention time characterized exposure conditions in the spill environment.

Application of a multistate model to estimate culvert effects on movement of small fishes

Science.gov (United States)

Norman, J.R.; Hagler, M.M.; Freeman, Mary C.; Freeman, B.J.

2009-01-01

While it is widely acknowledged that culverted road-stream crossings may impede fish passage, effects of culverts on movement of nongame and small-bodied fishes have not been extensively studied and studies generally have not accounted for spatial variation in capture probabilities. We estimated probabilities for upstream and downstream movement of small (30-120 mm standard length) benthic and water column fishes across stream reaches with and without culverts at four road-stream crossings over a 4-6-week period. Movement and reach-specific capture probabilities were estimated using multistate capture-recapture models. Although none of the culverts were complete barriers to passage, only a bottomless-box culvert appeared to permit unrestricted upstream and downstream movements by benthic fishes based on model estimates of movement probabilities. At two box culverts that were perched above the water surface at base flow, observed movements were limited to water column fishes and to intervals when runoff from storm events raised water levels above the perched level. Only a single fish was observed to move through a partially embedded pipe culvert. Estimates for probabilities of movement over distances equal to at least the length of one culvert were low (e.g., generally ???0.03, estimated for 1-2-week intervals) and had wide 95% confidence intervals as a consequence of few observed movements to nonadjacent reaches. Estimates of capture probabilities varied among reaches by a factor of 2 to over 10, illustrating the importance of accounting for spatially variable capture rates when estimating movement probabilities with capture-recapture data. Longer-term studies are needed to evaluate temporal variability in stream fish passage at culverts (e.g., in relation to streamflow variability) and to thereby better quantify the degree of population fragmentation caused by road-stream crossings with culverts. ?? American Fisheries Society 2009.

Accommodative loss after retinal cryotherapy.

Science.gov (United States)

Uno, Tsuyoshi; Okuyama, Michiko; Tanabe, Tatsuro; Kawamura, Ryosuke; Ideta, Hidenao

2009-01-01

To investigate the effects of peripheral retinal cryotherapy on accommodative amplitude in patients with retinal lattice degeneration. Prospective, observational case series. We studied 92 eyes in 69 patients (age range, 13 to 79 years) treated with cryotherapy for lattice degeneration between December 2001 and September 2004. Pretreatment and posttreatment accommodative amplitudes were measured. Acute accommodative loss was calculated from the difference between accommodative amplitudes before treatment and one week after treatment. We investigated the time course of accommodative amplitudes, acute accommodative loss in different age groups and in pretreatment accommodative amplitude groups, the influence of cryotherapy numbers on accommodative amplitude, and the influence of cryotherapy sites on accommodative amplitude. No significant difference was noted between pretreatment and posttreatment accommodative amplitudes in the overall subject cohort. Dividing subjects by age revealed significant decreases in accommodative amplitude only among patients in their 10s and 20s at one and three weeks after treatment. Accommodative amplitude was lowest among those in their 10s, followed by that among those in their 20s (P < .01). Accommodative amplitudes recovered to pretreatment level by six weeks. Acute accommodative loss was greatest in those in their 10s compared with other age groups (P < .01). A significant correlation was observed between acute accommodative loss and cryotherapy numbers (P = .03; r = 0.41). The decrease in accommodative amplitude was greatest at one week after treatment and recovered to pretreatment levels after six weeks. Accommodative amplitude showed the greatest decrease after cryotherapy among patients in their 10s and 20s. A decrease in accommodative amplitude was observed with increased numbers of cryotherapy spots administered.

The influence of interactions between accommodation and convergence on the lag of accommodation.

Science.gov (United States)

Schor, C

1999-03-01

Several models of myopia predict that growth of axial length is stimulated by blur. Accommodative lag has been suggested as an important source of blur in the development of myopia and this study has modeled how cross-link interactions between accommodation and convergence might interact with uncorrected distance heterophoria and refractive error to influence accommodative lag. Accommodative lag was simulated with two models of interactions between accommodation and convergence (one with and one without adaptable tonic elements). Simulations of both models indicate that both uncorrected hyperopia and esophoria increase the lag of accommodative and uncorrected myopia and exophoria decrease the lag or introduce a lead of accommodation in response to the near (40 cm) stimulus. These effects were increased when gain of either cross-link, accommodative convergence (AC/A) or convergence accommodation (CA/C), was increased within a moderate range of values while the other was fixed at a normal value (clamped condition). These effects were exaggerated when both the AC/A and CA/C ratios were increased (covaried condition) and affects of cross-link gain were negated when an increase of one cross-link (e.g. AC/A) was accompanied by a reduction of the other cross-link (e.g. CA/C) (reciprocal condition). The inclusion of tonic adaptation in the model reduced steady state errors of accommodation for all conditions except when the AC/A ratio was very high (2 MA/D). Combinations of cross-link interactions between accommodation and convergence that resemble either clamped or reciprocal patterns occur naturally in clinical populations. Simulations suggest that these two patterns of abnormal cross-link interactions could affect the progression of myopia differently. Adaptable tonic accommodation and tonic vergence could potentially reduce the progression of myopia by reducing the lag of accommodation.

Arctic warming will promote Atlantic-Pacific fish interchange

DEFF Research Database (Denmark)

Wisz, Mary; Broennimann, O.; Grønkjær, Peter

2015-01-01

the interchange of marine biota between the two seas. Here, we forecast the potential northward progression of 515 fish species following climate change, and report the rate of potential species interchange between the Atlantic and the Pacific via the Northwest Passage and the Northeast Passage. For this, we...... projected niche-based models under climate change scenarios and simulated the spread of species through the passages when climatic conditions became suitable. Results reveal a complex range of responses during this century, and accelerated interchange after 2050. By 2100 up to 41 species could enter......Throughout much of the Quaternary Period, inhospitable environmental conditions above the Arctic Circle have been a formidable barrier separating most marine organisms in the North Atlantic from those in the North Pacific. Rapid warming has begun to lift this barrier, potentially facilitating...

Fish screens at hydroelectric diversions

International Nuclear Information System (INIS)

Ott, R.F.

1994-01-01

Preventing downstream migrating fish from entering the turbines at hydroelectric projects is a standard mitigation goal of state and federal fishery management agencies. The object is to minimize the adverse impacts to the fish associated with the exclusion and passage through the bypass water conveyance facilities. In the western United States, most of the fishery management agencies have fish screen design criteria that focus on the approach and transportational velocities, maximum opening dimensions of the screen material, and the cleaning standards. Recently, more attention has been given to fish behavioral traits such as attraction and sustained and darting swimming speed, which has resulted in more attention to the position of the screens to the flow and the length of time the downstream migrants are exposed to the screens. Criteria for length of time of exposure, size and position of bypass, flow and velocities in the bypass entrances, discharge requirements back into the receiving water, and exposure to predation have created unique challenges to the fish screen designer. This paper discusses some of the more recent types of fixed fish screens that are being installed at hydroelectric plants that meet these challenges

Legal Protections in Public Accommodations Settings: A Critical Public Health Issue for Transgender and Gender-Nonconforming People

Science.gov (United States)

Reisner, Sari L; Hughto, Jaclyn M White; Dunham, Emilia E; Heflin, Katherine J; Begenyi, Jesse Blue Glass; Coffey-Esquivel, Julia; Cahill, Sean

2015-01-01

). Conclusions Discrimination in public accommodations is common and is associated with adverse health outcomes among transgender and gender-nonconforming adults in Massachusetts. Discrimination in health care settings creates a unique health risk for gender minority people. The passage and enforcement of transgender rights laws that include protections against discrimination in public accommodations—inclusive of health care—are a public health policy approach critically needed to address transgender health inequities. PMID:26219197

Fish pass assessment by remote control: a novel framework for quantifying the hydraulics at fish pass entrances

Science.gov (United States)

Kriechbaumer, Thomas; Blackburn, Kim; Gill, Andrew; Breckon, Toby; Everard, Nick; Wright, Ros; Rivas Casado, Monica

2014-05-01

Fragmentation of aquatic habitats can lead to the extinction of migratory fish species with severe negative consequences at the ecosystem level and thus opposes the target of good ecological status of rivers defined in the EU Water Framework Directive (WFD). In the UK, the implementation of the EU WFD requires investments in fish pass facilities of estimated 532 million GBP (i.e. 639 million Euros) until 2027 to ensure fish passage at around 3,000 barriers considered critical. Hundreds of passes have been installed in the past. However, monitoring studies of fish passes around the world indicate that on average less than half of the fish attempting to pass such facilities are actually successful. There is a need for frameworks that allow the rapid identification of facilities that are biologically effective and those that require enhancement. Although there are many environmental characteristics that can affect fish passage success, past research suggests that variations in hydrodynamic conditions, reflected in water velocities, velocity gradients and turbulences, are the major cues that fish use to seek migration pathways in rivers. This paper presents the first steps taken in the development of a framework for the rapid field-based quantification of the hydraulic conditions downstream of fish passes and the assessment of the attractivity of fish passes for salmonids and coarse fish in UK rivers. For this purpose, a small-sized remote control platform carrying an acoustic Doppler current profiler (ADCP), a GPS unit, a stereo camera and an inertial measurement unit has been developed. The large amount of data on water velocities and depths measured by the ADCP within relatively short time is used to quantify the spatial and temporal distribution of water velocities. By matching these hydraulic features with known preferences of migratory fish, it is attempted to identify likely migration routes and aggregation areas at barriers as well as hydraulic features that

Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2002 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

DeHart, Michele; Berggren, Thomas J.; Filardo, Margaret (Columbia Basin Fish and Wildlife Authority, Fish Passage Center, Portland, OR)

2003-09-01

The runoff volumes in 2002 were near average for the January to July period above Lower Granite Dam (80%) and The Dalles Dam (97%). The year 2002 hydrosystem operations and runoff conditions resulted in flows that were less than the seasonal Biological Opinion (Opinion) flow objectives at Lower Granite Dam for both the spring and summer period. The seasonal flow objectives for Priest Rapids and McNary dams were exceeded for the spring period, but at McNary Dam summer flow objectives were not met. While seasonal flow objectives were exceeded for the spring at McNary Dam, the 2002 season illustrated that Biological Opinion management to seasonal flow targets can result in conditions where a major portion of the juvenile fish migration migrates in conditions that are less than the flow objectives. The delay in runoff due to cool weather conditions and the inability of reservoirs to augment flows by drafting lower than the flood control elevations, resulted in flows less than the Opinion objectives until May 22, 2002. By this time approximately 73% of the yearling chinook and 56% of steelhead had already passed the project. For the most part, spill in 2002 was managed below the gas waiver limits for total dissolved gas levels and the NMFS action criteria for dissolved gas signs were not exceeded. The exception was at Lower Monumental Dam where no Biological Opinion spill occurred due to the need to conduct repairs in the stilling basin. Survival estimates obtained for PIT tagged juveniles were similar in range to those observed prior to 2001. A multi-year analysis of juvenile survival and the factors that affect it was conducted in 2002. A water transit time and flow relation was demonstrated for spring migrating chinook and steelhead of Snake River and Mid Columbia River origin. Returning numbers of adults observed at Bonneville Dam declined for spring chinook, steelhead and coho, while summer and fall chinook numbers increased. However, all numbers were far greater

Fish-Friendly Hydropower Turbine Development & Deployment: Alden Turbine Preliminary Engineering and Model Testing

Energy Technology Data Exchange (ETDEWEB)

Foust, J. [Voith Hydro, Inc., York, PA (USA); Hecker, G. [Alden Research Laboratory, Inc., Holden, MA (USA); Li, S. [Alden Research Laboratory, Inc., Holden, MA (USA); Allen, G. [Alden Research Laboratory, Inc., Holden, MA (USA)

2011-10-01

The Alden turbine was developed through the U.S. Department of Energy's (DOE's) former Advanced Hydro Turbine Systems Program (1994-2006) and, more recently, through the Electric Power Research Institute (EPRI) and the DOE's Wind & Water Power Program. The primary goal of the engineering study described here was to provide a commercially competitive turbine design that would yield fish passage survival rates comparable to or better than the survival rates of bypassing or spilling flow. Although the turbine design was performed for site conditions corresponding to 92 ft (28 m) net head and a discharge of 1500 cfs (42.5 cms), the design can be modified for additional sites with differing operating conditions. During the turbine development, design modifications were identified for the spiral case, distributor (stay vanes and wicket gates), runner, and draft tube to improve turbine performance while maintaining features for high fish passage survival. Computational results for pressure change rates and shear within the runner passage were similar in the original and final turbine geometries, while predicted minimum pressures were higher for the final turbine. The final turbine geometry and resulting flow environments are expected to further enhance the fish passage characteristics of the turbine. Computational results for the final design were shown to improve turbine efficiencies by over 6% at the selected operating condition when compared to the original concept. Prior to the release of the hydraulic components for model fabrication, finite element analysis calculations were conducted for the stay vanes, wicket gates, and runner to verify that structural design criteria for stress and deflections were met. A physical model of the turbine was manufactured and tested with data collected for power and efficiency, cavitation limits, runaway speed, axial and radial thrust, pressure pulsations, and wicket gate torque. All parameters were observed to fall

Disabling accommodation barriers: A study exploring how to better accommodate government employees with anxiety disorders.

Science.gov (United States)

Mellifont, Damian; Smith-Merry, Jennifer; Scanlan, Justin Newton

2016-11-22

Accommodating mental health in the workplace is challenging. Despite policy efforts to encourage the availability of mental health accommodations in the workplace, employees experiencing mental illness are missing out on accommodations that they need. To inform vocational rehabilitation professionals and managers in the public service of best practice accommodations for government employees with anxiety disorders. Thematic analysis was applied to data collected from the online Accommodating Government Employees with Anxiety Disorders Survey undertaken by 71 Australian public service employees diagnosed with at least one anxiety disorder. Our research results include theme and sub-theme representations of accommodations received, accommodations reported as missing, accommodations that study participants felt they couldn't request, along with rejected accommodations. From the study participants' accounts, three key findings supporting desirable vocational outcomes become apparent. First, that the availability of 'standard' flexible work arrangements, along with personalised accommodations, can assist persons with anxiety disorders (where needed) to reach and retain government positions. Second, the chief barriers reported to making accommodation requests revolve around fears of being stigmatised and penalised. Finally, there is a need for managerial decision-makers to remain open-minded, particularly when assessing requests for accommodations that may break from government norms.

Upper Caraş River (Danube watershed fish populations fragmentation – technical rehabilitation proposal

Directory of Open Access Journals (Sweden)

Voicu Răzvan

2018-01-01

Full Text Available We propose a technical solution for fish movement based on the flow of water over a spill threshold. Such barriers are common in the Danube system. The proposed system has a range of operating components which are easily detachable from the spill threshold, are resistant to corrosion and will not harm the fish. In fact, if designed to complement swimming abilities of target fish, it should provide adequate passage for both adults and juveniles. If implemented correctly, the design may offer a solution to help displaced fish recolonize upstream habitats.

Temporary Restoration of Bull Trout Passage at Albeni Falls Dam

Energy Technology Data Exchange (ETDEWEB)

Paluch, Mark; Scholz, Allan; McLellan, Holly [Eastern Washington University Department of Biology; Olson, Jason [Kalispel Tribe of Indians Natural Resources Department

2009-07-13

This study was designed to monitor movements of bull trout that were provided passage above Albeni Falls Dam, Pend Oreille River. Electrofishing and angling were used to collect bull trout below the dam. Tissue samples were collected from each bull trout and sent to the U. S. Fish and Wildlife Service Abernathy Fish Technology Center Conservation Genetics Lab, Washington. The DNA extracted from tissue samples were compared to a catalog of bull trout population DNA from the Priest River drainage, Lake Pend Oreille tributaries, and the Clark Fork drainage to determine the most probable tributary of origin. A combined acoustic radio or radio tag was implanted in each fish prior to being transported and released above the dam. Bull trout relocated above the dam were able to volitionally migrate into their natal tributary, drop back downstream, or migrate upstream to the next dam. A combination of stationary radio receiving stations and tracking via aircraft, boat, and vehicle were used to monitor the movement of tagged fish to determine if the spawning tributary it selected matched the tributary assigned from the genetic analysis. Seven bull trout were captured during electrofishing surveys in 2008. Of these seven, four were tagged and relocated above the dam. Two were tagged and left below the dam as part of a study monitoring movements below the dam. One was immature and too small at the time of capture to implant a tracking tag. All four fish released above the dam passed by stationary receivers stations leading into Lake Pend Oreille and no fish dropped back below the dam. One of the radio tags was recovered in the tributary corresponding with the results of the genetic test. Another fish was located in the vicinity of its assigned tributary, which was impassable due to low water discharge at its mouth. Two fish have not been located since entering the lake. Of these fish, one was immature and not expected to enter its natal tributary in the fall of 2008. The other

Umatilla River Fish Passage Operations Project : Annual Progress Report October 2007 - September 2008.

Energy Technology Data Exchange (ETDEWEB)

Bronson, James P.; Loffink, Ken; Duke, Bill

2008-12-31

Threemile Falls Dam (Threemile Dam), located near the town of Umatilla, is the major collection and counting point for adult salmonids returning to the Umatilla River. Returning salmon and steelhead were enumerated at Threemile Dam from June 7, 2007 to August 11, 2008. A total of 3,133 summer steelhead (Oncorhynchus mykiss); 1,487 adult, 1,067 jack, and 999 subjack fall Chinook (O. tshawytscha); 5,140 adult and 150 jack coho (O. kisutch); and 2,009 adult, 517 jack, and 128 subjack spring Chinook (O. tshawytscha) were counted. All fish were enumerated at the east bank facility. Of the fish counted, 1,442 summer steelhead and 88 adult and 84 jack spring Chinook were hauled upstream from Threemile Dam. There were 1,497 summer steelhead; 609 adult, 1,018 jack and 979 subjack fall Chinook; 5,036 adult and 144 jack coho; and 1,117 adult, 386 jack and 125 subjack spring Chinook either released at, or allowed to volitionally migrate past, Threemile Dam. Also, 110 summer steelhead; 878 adult and 43 jack fall Chinook; and 560 adult and 28 jack spring Chinook were collected as broodstock for the Umatilla River hatchery program. In addition, there were 241 adult and 15 jack spring Chinook collected at Threemile Dam for outplanting in the South Fork Walla Walla River and Mill Cr, a tributary of the mainstem Walla Walla River. The Westland Canal juvenile facility (Westland), located near the town of Echo at river mile (RM) 27, is the major collection point for out-migrating juvenile salmonids and steelhead kelts. The canal was open for 158 days between February 11, 2008 and July 18, 2008. During that period, fish were bypassed back to the river 150 days and were trapped 6 days. There were also 2 days when fish were directed into and held in the canal forebay between the time the bypass was closed and the trap opened. An estimated 64 pounds of fish were transported from the Westland trapping facility. Approximately 25.8% of the fish transported were salmonids. In addition, one

Biological Evaluations of an Off-Stream Channel, Horizontal Flat-Plate Fish Screen-The Farmers Screen

Science.gov (United States)

Mesa, Matthew G.; Rose, Brien P.; Copeland, Elizabeth S.

2010-01-01

Screens are commonly installed at water diversion sites to reduce entrainment of fish. Recently, the Farmers Irrigation District in Hood River, Oregon, developed a new flat-plate screen design that offers passive operation and may result in reduced operation and installation costs to irrigators. To evaluate the performance (its biological effect on fish) of this type of screen, two size classes of juvenile coho salmon (Oncorhynchus kistuch) were released over a small version of this screen in the field-the Herman Creek screen. The performance of the screen was evaluated over a range of inflow [0.02 to 0.42 m3/s (cubic meters per second)] and diversion flows (0.02 to 0.34 m3/s) at different weir wall heights. The mean approach velocities for the screen ranged from 0 to 5 cm/s (centimeters per second) and mean sweeping velocities ranged from 36 to 178 cm/s. Water depths over the screen surface ranged from 1 to 25 centimeters and were directly related to weir wall height and inflow. Passage of juvenile coho salmon over the screen under a variety of hydraulic conditions did not severely injure them or cause delayed mortality. For all fish, the mean percentage of body surface area that was injured after passage over the screen ranged from about 0.4 to 3.0%. This occurred even though many fish contacted the screen surface during passage. No fish were observed becoming impinged on the screen surface (greater than 1 second contact with the screen). When operated within its design criteria (diversion flows of about 0.28 m3/s), the screen provided safe and effective downstream passage of juvenile salmonids under a variety of hydraulic conditions. However, we do not recommend operating the screen at inflows less than 0.14 m3/s (5 ft3/s) because water depth can get quite shallow and the screen can completely dewater, particularly at very low flows.

Variações temporais na passagem de peixes pelo elevador da Usina Hidrelétrica de Santa Clara, rio Mucuri, leste brasileiro Temporal patterns of fish passage in Santa Clara Power Plant's fish lift, Mucuri River, east Brazil

Directory of Open Access Journals (Sweden)

Paulo dos S. Pompeu

2006-06-01

Full Text Available O presente estudo teve como objetivo determinar padrões temporais na passagem de peixes pelo elevador da Usina Hidrelétrica de Santa, localizado no rio Mucuri. Durante quatro meses, de novembro de 2003 a março de 2004, foram realizados ciclos de transposição a cada duas horas, quando todos os indivíduos foram contados e identificados. Durante este período foram transpostos 67.838 indivíduos de 31 espécies. A abundância de Characiformes migradores no elevador foi maior no período diurno, enquanto Siluriformes foram observados em maior quantidade à noite. A abundância de peixes no elevador foi relacionada significativamente com as vazões no rio Mucuri. O padrão encontrado torna possível a melhor utilização do elevador, priorizando sua operação durante o dia e em períodos de maior vazão.The current study had the objective of determining temporal patterns of fish passage in Santa Clara Power Plant's fish lift, Mucuri River. During four months, from November 2003 to March 2004, transposition cycles were performed each two hours, when the specimens were counted and identified. During this migration period 67,838 individuals of 31 species passed through the lift. Migratory Characiformes abundance was larger during the day, whereas the Siluriformes were registered mainly at night. Fish abundance in the lift was significantly related to the Mucuri river flow. The temporal pattern found makes possible a better utilization of the lift, focusing cycles during the day and high flows periods.

[Energy and memory efficient calculation of the accommodation demand in the artificial accommodation system].

Science.gov (United States)

Nagel, J A; Beck, C; Harms, H; Stiller, P; Guth, H; Stachs, O; Bretthauer, G

2010-12-01

Presbyopia and cataract are gaining more and more importance in the ageing society. Both age-related complaints are accompanied with a loss of the eye's ability to accommodate. A new approach to restore accommodation is the Artificial Accommodation System, an autonomous micro system, which will be implanted into the capsular bag instead of a rigid intraocular lens. The Artificial Accommodation System will, depending on the actual demand for accommodation, autonomously adapt the refractive power of its integrated optical element. One possibility to measure the demand for accommodation non-intrusively is to analyse eye movements. We present an efficient algorithm, based on the CORDIC technique, to calculate the demand for accommodation from magnetic field sensor data. It can be shown that specialised algorithms significantly shorten calculation time without violating precision requirements. Additionally, a communication strategy for the wireless exchange of sensor data between the implants of the left and right eye is introduced. The strategy allows for a one-sided calculation of the demand for accommodation, resulting in an overall reduction of calculation time by 50 %. The presented methods enable autonomous microsystems, such as the Artificial Accommodation System, to save significant amounts of energy, leading to extended autonomous run-times. © Georg Thieme Verlag KG Stuttgart · New York.

[Effects of orthokeratology lenses on the magnitude of accommodative lag and accommodativeconvergence/accommodation].

Science.gov (United States)

Ren, Qiujin; Yue, Hui; Zhou, Qing

2016-02-01

To evaluate the change in accommodative lag and accommodation convergence/accommodation (AC/A) after patients with myopia wear orthokeratology lenses. 
 A total of 48 myopic subjects (a test group), who wore orthokeratology lenses regularly, and 48 myopic subjects (a control group), who wore spectacles regularly, were enrolled for this study from January 2011 to January 2013 in Optometric Center, the Forth Hospital of Changsha. Accommodative lag was measured by fused cross cylinder method, where the patients should gaze at the front optotypes 40 cm away. Gradient of the AC/A ratio was measured by Von Grafe method to check closer distance heterophoria. Accommodative lag and AC/A ratio were analyzed by statistics.
 After 1-year follow-up, accommodative lag and AC/A rate in patients with low or moderate myopia in the test group was decreased in 1, 3, 6 months or 1 year compared with that in the control group (Paccommodative lag and high AC/A rate in patients with low or moderate myopia. The relationship between accommodation and convergence is improved by orthokeratology lenses. Orthokeratology is an effective way to control myopia.

Laboratory Studies on the Effects of Shear on Fish

Energy Technology Data Exchange (ETDEWEB)

Neitzel, Duane A.; Richmond, Marshall C.; Dauble, Dennis D.; Mueller, Robert P.; Moursund, Russell A.; Abernethy, Cary S.; Guensch, Greg R.

2000-09-20

The overall objective of our studies was to specify an index describing the hydraulic force that fish experience when subjected to a shear environment. Fluid shear is a phenomenon that is important to fish. However, elevated levels of shear may result in strain rates that injure or kill fish. At hydroelectric generating facilities, concerns have been expressed that strain rates associated with passage through turbines, spillways, and fish bypass systems may adversely affect migrating fish. Development of fish friendly hydroelectric turbines requires knowledge of the physical forces (injury mechanisms) that impact entrained fish and the fish's tolerance to these forces. It requires up-front, pre-design specifications for the environmental conditions that occur within the turbine system, in other words, determining or assuming that those conditions known to injure fish will provide the descriptions of conditions that engineers must consider in the design of a turbine system. These biological specifications must be carefully and thoroughly documented throughout the design of a fish friendly turbine. To address the development of biological specifications, we designed and built a test facility where juvenile fish could be subjected to a range of shear environments and quantified their biological response.

Marine litter on the seafloor of the Faial-Pico Passage, Azores Archipelago.

Science.gov (United States)

Rodríguez, Yasmina; Pham, Christopher K

2017-03-15

Plastic pollution in the marine environment attracts much attention from both researchers and the general public. Plastic items and other debris are commonly observed everywhere in the ocean, from the surface down to the deep ocean floor. In this study, we analysed 45.2km of video footage, collected during 56 transects surveying the seafloor of the Faial-Pico Passage in order to quantify the abundance of marine litter and its interactions with benthic fauna. The footage was collected by a Remotely Operated Vehicle (ROV) and a manned submersible at depths ranging between 40 and 525m. The mean litter density in the passage was 0.26±0.03 items·100m -1 (±SE) and was significantly higher between 151 and 250m compared to other depth strata. Overall, derelict fishing gear, mostly made of plastic, were the most common objects found on the seafloor, representing 64% of all items. Although we observed few evidence of direct deleterious effects by the litter, interactions with fauna were observed in more than half of the items. This study makes an important contribution in quantifying the abundance of marine litter on the seafloor of the Azores. The location of the Faial-Pico Passage, close to shore, makes it an appropriate site for long-term monitoring of litter on the seafloor and evaluate the efficiency of upcoming public policies aimed at reducing litter input into the oceans. Copyright © 2017 Elsevier Ltd. All rights reserved.

Smolt Passage Behavior and Flow-Net Relationships in the Forebay of John Day Dam, 1983 [Amended] Annual Report of Research.

Energy Technology Data Exchange (ETDEWEB)

Giorgi, Albert E.

1984-04-01

During 1983, the research program had three separate but complementary phases--monitoring current patterns in the forebay, defining fish distribution with purse seine sampling, and describing the migration routes of salmonid smolts using radio tracking techniques. Preliminary results from the radio-tracking and purse seining operations in FY83 suggest that the discharge from the John Day River and the turbid plume it forms in the forebay may have a pronounced effect on the distribution of smolts, especially chinook and sockeye salmon, as they approach the dam. The implication of these data is that the plume may be shunting salmon toward the Washington (spill) side of the river where they would be more susceptible to spill passage. This resulted in higher spill passage of tagged chinook salmon than the proportion of water being spilled. In contrast, spillway passage of steelhead not influenced by the plume is approximately the same as the proportion of water being spilled. These findings are based on limited data and must be considered preliminary at this time. Data describing the current patterns have just recently been reduced to a usable format and have not yet been correlated with findings from radio tracking and purse seining. Such data will be incorporated into an overall analysis of the relations of current patterns and John Day River discharge to fish migration patterns. Representative examples of prevailing current patterns during the spring migration have been completed and are included in this document.

A Preliminary Assessment of Barotrauma Injuries and Acclimation Studies for Three Fish Species

Energy Technology Data Exchange (ETDEWEB)

Brown, Richard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Walker, Ricardo W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephenson, John R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-12-15

Fish that pass hydro structures either through turbine passage, deep spill, or other deep pathways can experience rapid decreases in pressure that can result in barotrauma. In addition to morphology and physiology of the fish’s swim bladder, the severity of barotrauma is directly related to the volume of undissolved gas in fish prior to rapid decompression and the lowest pressure the fish experience as they pass hydro structures (termed the “nadir”). The volume of undissolved gas in fish is influenced by the depth of acclimation (the pressure at which the fish is neutrally buoyant); therefore, determining the depth where fish are neutrally buoyant is a critical precursor to determining the relationship between pressure changes and injury or mortality.

EBooks and Accommodations: Is This the Future of Print Accommodation?

Science.gov (United States)

Cavanaugh, Terence

2002-01-01

This article explains the three components of eBooks: an eBook file, software to read the eBook, and a hardware device to read it on. The use of eBooks for students with special needs, the advantages of eBooks, built in accommodations, and creating accommodations are discussed. EBook resources are included. (Contains references.) (CR)

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

Energy Technology Data Exchange (ETDEWEB)

Jacobson, Paul T. [Electric Power Research Institute; Amaral, Stephen V. [Alden Research Laboratory; Castro-Santos, Theodore [U.S. Geological Survey; Giza, Dan [Alden Research Laboratory; Haro, Alexander J. [U.S. Geological Survey; Hecker, George [Alden Research Laboratory; McMahon, Brian [Alden Research Laboratory; Perkins, Norman [Alden Research Laboratory; Pioppi, Nick [Alden Research Laboratory

2012-12-31

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 three 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 speeds and

Nonverbal Accommodation in Healthcare Communication

OpenAIRE

D’Agostino, Thomas A.; Bylund, Carma L.

2013-01-01

This exploratory study examined patterns of nonverbal accommodation within healthcare interactions and investigated the impact of communication skills training and gender concordance on nonverbal accommodation behavior. The Nonverbal Accommodation Analysis System (NAAS) was used to code the nonverbal behavior of physicians and patients within 45 oncology consultations. Cases were then placed in one of seven categories based on patterns of accommodation observed across the interaction. Results...

Retinal image quality during accommodation.

Science.gov (United States)

López-Gil, Norberto; Martin, Jesson; Liu, Tao; Bradley, Arthur; Díaz-Muñoz, David; Thibos, Larry N

2013-07-01

We asked if retinal image quality is maximum during accommodation, or sub-optimal due to accommodative error, when subjects perform an acuity task. Subjects viewed a monochromatic (552 nm), high-contrast letter target placed at various viewing distances. Wavefront aberrations of the accommodating eye were measured near the endpoint of an acuity staircase paradigm. Refractive state, defined as the optimum target vergence for maximising retinal image quality, was computed by through-focus wavefront analysis to find the power of the virtual correcting lens that maximizes visual Strehl ratio. Despite changes in ocular aberrations and pupil size during binocular viewing, retinal image quality and visual acuity typically remain high for all target vergences. When accommodative errors lead to sub-optimal retinal image quality, acuity and measured image quality both decline. However, the effect of accommodation errors of on visual acuity are mitigated by pupillary constriction associated with accommodation and binocular convergence and also to binocular summation of dissimilar retinal image blur. Under monocular viewing conditions some subjects displayed significant accommodative lag that reduced visual performance, an effect that was exacerbated by pharmacological dilation of the pupil. Spurious measurement of accommodative error can be avoided when the image quality metric used to determine refractive state is compatible with the focusing criteria used by the visual system to control accommodation. Real focusing errors of the accommodating eye do not necessarily produce a reliably measurable loss of image quality or clinically significant loss of visual performance, probably because of increased depth-of-focus due to pupil constriction. When retinal image quality is close to maximum achievable (given the eye's higher-order aberrations), acuity is also near maximum. A combination of accommodative lag, reduced image quality, and reduced visual function may be a useful

Smolt Passage Behavior and Flow-Net Relationships in the Forebay of John Day Dam, 1983 Annual Report of Research.

Energy Technology Data Exchange (ETDEWEB)

Giorgi, Albert E.

1984-04-01

During 1983, the research program had three separate but complementary phases - monitoring current patterns in the forebay, defining fish distribution with purse seine sampling, and describing the migration routes of salmonid smolts using radio tracking techniques. Preliminary results from the radio-tracking and purse seining operations in FY 1983 suggest that the discharge from the John Day River and the turbid plume it forms in the forebay may have a pronounced effect on the distribution of smolts, especially chinook and sockeye salmon, as they approach the dam. The implication of these data is that the plume may be shunting salmon toward the Washington (spill) side of the river where they would be more susceptible to spill passage. This resulted in higher spill passage of tagged chinook salmon than the proportion of water being spilled. In contrast, sillway passage of steelhead not influenced by the plume is approximately the same as the proportion of water being spilled. These findings are based on limited data and must be considered preliminary at this time. Data describing the current patterns have just recently been reduced to a usable format and have not yet been correlated with findings from radio tracking and purse seining. Such data will be icorporated into an overall analysis of the relations of current patterns and John Day River discharge to fish migration patterns. Representative examples of prevailing current patterns during the spring migration have been completed and are included in this document. 10 refs., 14 figs., 6 tabs.

Passage of American shad: paradigms and realities

Science.gov (United States)

Haro, Alex; Castro-Santos, Theodore

2012-01-01

Despite more than 250 years of development, the passage of American shad Alosa sapidissima at dams and other barriers frequently remains problematic. Few improvements in design based on knowledge of the swimming, schooling, and migratory behaviors of American shad have been incorporated into passage structures. Large-scale technical fishways designed for the passage of adult salmonids on the Columbia River have been presumed to have good performance for American shad but have never been rigorously evaluated for this species. Similar but smaller fishway designs on the East Coast frequently have poor performance. Provision of effective downstream passage for both juvenile and postspawning adult American shad has been given little consideration in most passage projects. Ways to attract and guide American shad to both fishway entrances and downstream bypasses remain marginally understood. The historical development of passage structures for American shad has resulted in assumptions and paradigms about American shad behavior and passage that are frequently unsubstantiated by supporting data or appropriate experimentation. We propose that many of these assumptions and paradigms are either unfounded or invalid and that significant improvements to American shad upstream and downstream passage can be made via a sequential program of behavioral experimentation, application of experimental results to the physical and hydraulic design of new structures, and controlled tests of large-scale prototype structures in the laboratory and field.

Survival and Passage of Yearling and Subyearling Chinook Salmon and Steelhead at The Dalles Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Skalski, J. R.; Carlson, Thomas J.; Ploskey, Gene R.; Weiland, Mark A.; Deng, Zhiqun; Fischer, Eric S.; Hughes, James S.; Khan, Fenton; Kim, Jin A.; Townsend, Richard L.

2011-12-01

The acoustic telemetry study reported here was conducted by researchers at Pacific Northwest National Laboratory (PNNL) and the University of Washington (UW) for the U.S. Army Corps of Engineers, Portland District (USACE). The purpose of the study was to estimate dam passage survival and other performance measures for yearling and subyearling Chinook salmon and steelhead at The Dalles Dam as stipulated by the 2008 Biological Opinion on operation of the Federal Columbia River Power System (FCRPS) and 2008 Columbia Basin Fish Accords.

High-flow, low-head pumps provide safe passage for Pacific salmon

International Nuclear Information System (INIS)

Anon

2004-01-01

The installation of 29 ultra-low head, high capacity submersible pump and auxiliary equipment at the Rocky Reach Dam in Washington State to allow juvenile salmon safe passage on their journey down the Columbia River to the Pacific Ocean is described. The reputed cost of the project is US$160 million; its purpose is to get juvenile salmon safely around the Rocky Reach Dam without interfering with the dam's original mission of generating electric power. The project is the most expensive fish bypass on any Columbia River dam. Getting the salmon safely around the dam is intended to reduce the impact of hydroelectric power projects on the basin's salmon stocks which are now estimated at less than 10 per cent of their historic size, despite major hatchery programs. The Columbia River has the second largest volume flow of any river in the United States, and millions of people depend on it for employment in water-related industries, and for transportation. The new horizontally installed propeller pump was developed by ITT Flygt; it utilizes planetary gear reduced to match the motor speed with the propeller rpm. Each 90 kW propeller pump has a flow rate of seven cubic meters per second at a head of 0.55 metres. The auxiliary equipment includes 10 racks of flap gates to prevent reverse flow, electric controls, remote supervision, testing, installation and maintenance facilities. It is anticipated that the new bypass will allow the Chelan County Public Utility Department, owners of the facility, to phase out all current spills, except for a 16 per cent spill for 40 days each spring for Sockeye salmon which tend to travel too deep to use the bypass. Prior to installation of this new facility, 60 to 70 per cent of average daily flow in the spring and summer had to be sacrificed to accommodate all species of salmon and steelhead, with corresponding losses of power generating capacity

Exploring the Relationship Between Students with Accommodations and Instructor Self-Efficacy in Complying with Accommodations

Directory of Open Access Journals (Sweden)

Anna M. Wright

2017-06-01

Full Text Available The willingness and flexibility of university instructors to comply with and provide accommodations for students with disabilities is critical to academic success. The authors examine how communication between students needing accommodations and university instructors impacts instructor self-efficacy, or instructors’ perception that they can meet the accommodation. Specifically, the authors’ explored the relationship between student self-disclosure of a disability and instructor empathy, flexibility, and self-efficacy in meeting student accommodation needs. Results revealed that the more a student self-discloses about a needed accommodation, the more self-efficacy an instructor has in making that accommodation. For the low-disclosure condition, empathy and flexibility were both significant predictors of self-efficacy, whereas, for the high-disclosure condition, only flexibility was a significant predictor of self-efficacy. Finally, instructors’ levels of empathy and flexibility both decreased after reading both the high and low self-disclosure scenarios.

Legal Protections in Public Accommodations Settings: A Critical Public Health Issue for Transgender and Gender-Nonconforming People.

Science.gov (United States)

Reisner, Sari L; Hughto, Jaclyn M White; Dunham, Emilia E; Heflin, Katherine J; Begenyi, Jesse Blue Glass; Coffey-Esquivel, Julia; Cahill, Sean

2015-09-01

health care was independently associated with adverse self-reported health, adjusting for discrimination in other public accommodations settings. Overall, 65% of respondents reported public accommodations discrimination in the past 12 months. The 5 most prevalent discrimination settings were transportation (36%), retail (28%), restaurants (26%), public gatherings (25%), and health care (24%). Public accommodations discrimination in the past 12 months in health care settings was independently associated with a 31% to 81% increased risk of adverse emotional and physical symptoms and a 2-fold to 3-fold increased risk of postponement of needed care when sick or injured and of preventive or routine health care, adjusting for discrimination in other public accommodations settings (which also conferred an additional 20% to 77% risk per discrimination setting endorsed). Discrimination in public accommodations is common and is associated with adverse health outcomes among transgender and gender-nonconforming adults in Massachusetts. Discrimination in health care settings creates a unique health risk for gender minority people. The passage and enforcement of transgender rights laws that include protections against discrimination in public accommodations-inclusive of health care-are a public health policy approach critically needed to address transgender health inequities. © 2015 Milbank Memorial Fund.

Accommodation | Information | Indian Academy of Sciences

Indian Academy of Sciences (India)

Accommodation. The Academy has made arrangements to accommodate all participants who have requested for it. Details ​of accommodation ​have been sent to ​all registered participants. Volunteers at the airport will assist the participants in reaching their respective places of accommodation. For any queries ...

Studies on water turbine runner which fish can pass through: In case of single stage axial runner

International Nuclear Information System (INIS)

Shimizu, Yukimari; Maeda, Takao; Nagoshi, Osamu; Ieda, Kazuma; Shinma, Hisako; Hagimoto, Michiko

1994-01-01

The relationship between water turbine runner design and operation and the safe passage of fish through the turbine is studied. The kinds of fish used in the tests are a dace, a sweet fish and a small salmon. A single stage axial runner is used. The velocity and pressure distributions were measured inside the turbine casing and along the casing wall. Many pictures showing fish passing through the rotating runner were taken and analyzed. The swimming speed of the fish was examined from video recordings. Fish pass through the runner more rapidly when they can determine and choose the easier path. Injury and mortality of fish are affected by the runner speed and the location of impact of the runner on the fish body

Passage relevance models for genomics search

Directory of Open Access Journals (Sweden)

Frieder Ophir

2009-03-01

Full Text Available Abstract We present a passage relevance model for integrating syntactic and semantic evidence of biomedical concepts and topics using a probabilistic graphical model. Component models of topics, concepts, terms, and document are represented as potential functions within a Markov Random Field. The probability of a passage being relevant to a biologist's information need is represented as the joint distribution across all potential functions. Relevance model feedback of top ranked passages is used to improve distributional estimates of query concepts and topics in context, and a dimensional indexing strategy is used for efficient aggregation of concept and term statistics. By integrating multiple sources of evidence including dependencies between topics, concepts, and terms, we seek to improve genomics literature passage retrieval precision. Using this model, we are able to demonstrate statistically significant improvements in retrieval precision using a large genomics literature corpus.

Development of live attenuated Streptococcus agalactiae vaccine for tilapia via continuous passage in vitro.

Science.gov (United States)

Li, L P; Wang, R; Liang, W W; Huang, T; Huang, Y; Luo, F G; Lei, A Y; Chen, M; Gan, X

2015-08-01

Fish Streptococcus agalactiae (S. agalactiae) seriously harms the world's aquaculture industry and causes huge economic losses. This study aimed to develop a potential live attenuated vaccine of S. agalactiae. Pre-screened vaccine candidate strain S. agalactiae HN016 was used as starting material to generate an attenuated strain S. agalactiae YM001 by continuous passage in vitro. The biological characteristics, virulence, and stability of YM001 were detected, and the protective efficacy of YM001 immunization in tilapia was also determined. Our results indicated that the growth, staining, characteristics of pulsed-field gel electrophoresis (PFGE) genotype, and virulence of YM001 were changed significantly as compared to the parental strain HN016. High doses of YM001 by intraperitoneal (IP) injection (1.0 × 10(9) CFU/fish) and oral gavage (1.0 × 10(10) CFU/fish) respectively did not cause any mortality and morbidity in tilapia. The relative percent survivals (RPSs) of fishes immunized with YM001 (1.0 × 10(8) CFU/fish, one time) via injection, immersion, and oral administration were 96.88, 67.22, and 71.81%, respectively, at 15 days, and 93.61, 60.56, and 53.16%, respectively, at 30 days. In all tests with 1-3 times of immunization in tilapia, the dosages at 1 × 10(8) and 1 × 10(9) CFU/fish displayed the similar best results, whereas the immunoprotection of the dosages at 1 × 10(6) and 1 × 10(7) CFU/fish declined significantly (P 0.05). The level of protective antibody elicited by oral immunization was significantly higher compared to that of the control group (P S. agalactiae strain YM001; oral immunization of tilapia with this strain produced a good immune protection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assemblages of micronektonic fishes and invertebrates in a gradient of regional warming along the Western Antarctic Peninsula

Science.gov (United States)

Parker, Melanie L.; Fraser, William R.; Ashford, Julian; Patarnello, Tomaso; Zane, Lorenzo; Torres, Joseph J.

2015-12-01

Micronektonic fishes and invertebrates were sampled with 32 midwater trawls at nine sites along the Western Antarctic Peninsula (WAP) in the austral fall (March-April) of 2010. Study sites were located within four hypothesized hydrographic regions: near Joinville Island in Region I, at Croker Passage, near Anvers Island, and near Renaud Island in Region II, within Marguerite Bay and the Marguerite Trough in Region III, and near Charcot Island in Region IV. A total of 62 taxa representing 12 taxonomic groups of pelagic invertebrates and 9 families of fish were captured, but assemblages were dominated by only a few species. The most numerically abundant taxa were the euphausiids, Thysanoessa macrura, Euphausia superba, and E. crystallorophias, combining to contribute nearly 79% of the total catch. Biomass dominants included E. superba, which contributed more than 44% of the total catch, the notothenioid Pleuragramma antarctica, and the salp, Salpa thompsoni. A comparison of total catches among sites revealed that the largest volumetric abundances and biomasses were captured at the Marguerite Bay site. Cluster analysis of abundance data identified distinct multispecies assemblages at Joinville Island in Region I, Croker Passage in Region II, Marguerite Bay in Region III, and Charcot Island in Region IV. A fifth distinct assemblage included samples from sites near Anvers and Renaud Island in Region II, and from the Marguerite Trough in Region III. Assemblages at Joinville Island and Croker Passage were both dominated by E. superba and S. thompsoni, but hydrographic conditions at Joinville Island favored a neritic assemblage, underscored by substantial numbers of P. antarctica. The assemblage at Croker Passage was more oceanic in nature with major inputs from the myctophid, Electrona antarctica and the hyperiid amphipod, Themisto gaudichaudii. Marguerite Bay and Charcot Island were well-mixed assemblages with strong representation by both neritic and oceanic fauna. The

Vestibular-ocular accommodation reflex in man

Science.gov (United States)

Clark, B.; Randle, R. J.; Stewart, J. D.

1975-01-01

Stimulation of the vestibular system by angular acceleration produces widespread sensory and motor effects. The present paper studies a motor effect which has not been reported in the literature, i.e., the influence of rotary acceleration of the body on ocular accommodation. The accommodation of 10 young men was recorded before and after a high-level deceleration to zero velocity following 30 sec of rotating. Accommodation was recorded continuously on an infrared optometer for 110 sec under two conditions: while the subjects observed a target set at the far point, and while they viewed the same target through a 0.3-mm pinhole. Stimulation by high-level rotary deceleration produced positive accommodation or a pseudomyopia under both conditions, but the positive accommodation was substantially greater and lasted much longer during fixation through the pinhole. It is hypothesized that this increase in accommodation is a result of a vestibular-ocular accommodation reflex.

Influence of accommodative lag upon the far-gradient measurement of accommodative convergence to accommodation ratio in strabismic patients.

Science.gov (United States)

Miyata, Manabu; Hasebe, Satoshi; Ohtsuki, Hiroshi

2006-01-01

To determine the influence of the lag of accommodation (LOA) on the accommodative convergence to accommodation (AC/A) ratio measured by the far-gradient method in strabismic patients. The AC/A ratio was measured with a distance target viewed with and without -3.00 diopter (D) addition lenses in 63 patients with different types of strabismus (age range, 7-34 years; range of strabismic angle, -60 to +40 prism diopters; refractive error range, -7.33 to +6.63 D). The LOA for the same lens was measured with an open-view-type autorefractometer. The stimulus AC/A ratio and the AC/A ratio adjusted by the individually measured LOA (adjusted AC/A ratio) were compared. The mean +/- SD of the LOA to the -3.00 D lenses was 1.06 +/- 0.43 D. The mean adjusted AC/A ratio was 41% greater than the stimulus AC/A ratio. The LOA differed widely among patients (0.13 to 2.14 D), and a large LOA tended to appear in myopic or young patients. The AC/A ratio obtained using the conventional far-gradient method is significantly biased by the LOA, and thus does not always represent the actual relationship between accommodation and vergence control systems. Copyright Japanese Ophthalmological Society 2006.

Selectivity of fish ladders: a bottleneck in Neotropical fish movement

Directory of Open Access Journals (Sweden)

Carlos Sérgio Agostinho

their proportions in the downriver stretch: fish samples in the ladder were clearly dominated by a few species, including some that do not need to be translocated. Thus, selectivity constitutes an important bottleneck to initiatives for translocating fish aimed at conserving their stocks or biodiversity. It is urgent to review the decision-making process for the construction of fish passages and to evaluate the functioning of those already operating.

Medial rectus Faden operations with or without recession for partially accommodative esotropia associated with a high accommodative convergence to accommodation ratio.

Science.gov (United States)

Akar, Serpil; Gokyigit, Birsen; Sayin, Nihat; Demirok, Ahmet; Yilmaz, Omer Faruk

2013-01-01

To evaluate the results of Faden operations on the medial rectus (MR) muscles with or without recession for the treatment of partially accommodative esotropia associated with a high accommodative convergence to accommodation (AC : A) ratio and to determine whether there was a decrease in the effects of posterior fixation over time. In this retrospective study, 108 of 473 patients who underwent surgery for partially accommodative esotropia with a high AC : A ratio received Faden operations on both MR muscles, and 365 received symmetric MR muscle recessions combined with a Faden operation. For the Faden operation, a satisfactory outcome of 76.9% at 1 month postoperation, decreased to 71.3% by the final follow-up visit (mean 4.8 years). A moderate positive correlation was observed between the increase in the postoperative near deviation and postoperative time. For the Faden operations combined with MR recession, a satisfactory outcome of 78.9% at 1 month post-operation, decreased to 78.4% by the final follow-up visit. A Faden operation of the MR muscles with or without recession is an effective surgical option for treating partially accommodative esotropia associated with a high AC : A ratio. For Faden operations of the MR muscles without recession, the effects of the posterior fixation decline over time.

Migratory behavior of adult sea lamprey and cumulative passage performance through four fishways

Science.gov (United States)

Castro-Santos, Theodore R.; Shi, Xiaotao; Haro, Alexander

2017-01-01

This article describes a study of PIT-tagged sea lamprey (Petromyzon marinus) ascending four fishways comprising three designs at two dams on the Connecticut River, USA. Migration between dams was rapid (median migration rate = 23 km·day−1). Movement through the fishways was much slower, however (median = 0.02–0.33 km·day−1). Overall delay at dams was substantial (median = 13.6–14.6 days); many fish failed to pass (percent passage ranged from 29% to 55%, depending on fishway), and repeated passage attempts compounded delay for both passers and failers. Cox regression revealed that fishway entry rates were influenced by flow, temperature, and diel cycle, with most lampreys entering at night and at elevated flows, but with no apparent effect of sex or length. Overall delay was influenced by slow movement through the fishways, but repeated failures were the primary factor determining delay. These data suggest that although some lamprey were able to pass fishways, they did so with difficulty, and delays incurred as they attempted to pass may act to limit their distribution within their native range.

Accommodative Ability in Prepresbyopic Diabetic Patients

Directory of Open Access Journals (Sweden)

Mohammad Etezad Razavi

2015-04-01

Full Text Available Introduction: To compare various accommodative parameters in prepresbyopic diabetic patients with age-matched healthy individuals. Materials and Methods: Study populationconsisted of 32 younger-onset diabetic patients (30-40 years of age and 28 age-matched healthy normal individuals. Using the best correction for distance visual acuity (20.20 by Snellen chart, multiple accommodative ability tests such as near point of accommodation, accommodative amplitude, negative or positive accommodative facility and near point of convergence were measured in both groups. Results: Mean near point of accommodation in diabetic patients was significantly greater than the control group (18.5±4.4 centimeters [cm] versus 9.5±2 centimeters, p= 0.000. Mean accommodative amplitude was (5.93±1.75 Diopter (D and (10.95±2.16 Diopter in diabetics and normal individuals, respectively (p=0.000. Mean accommodation facility was (3.19±3.04 cycle/minute [cyl/min] in patients and 10.01±5.09 cycle/minute in the control group (p= 0.000. Mean positive relative accommodation was (–3.37±1.19 D in diabetic and (-2.11±0.99 D in healthy participants (p=0.000. Mean negative relative accommodation was lower in diabetic patients compared with the control group, however, this difference did not reach statistical significance (2.61±0.65 D versus (2.61±0.60 D, p= 0.23. Mean near point of convergence was (8.23±1.43 cm and (7.13±0.67 cm in normal and diabetic groups, respectively which had insignificant difference (p= 0.45. Conclusion: Majority of accommodative ability functions decreased in prepresbyopic diabetic patients. Early detection and rehabilitation of such patients with corrective near spectacles are strongly recommended.

Treatment of Partly Accommodative Esotropia With a High Accommodative Convergence-Accommodation Ratio

NARCIS (Netherlands)

H.J. Simonsz (Huib)

1988-01-01

textabstractIn the June 1987 issue of the Archives, the results were published of a study by Kushner et al1 on the treatment of accommodative convergence excess, with bilateral medial rectus recessions or recessions with 14-mm posterior fixation sutures. Posterior fixation surgery was considered an

The effects of power plant passage on zooplankton mortalities: Eight years of study at the Donald C. Cook Nuclear Plant

International Nuclear Information System (INIS)

Evans, M.S.; Warren, G.J.; Page, D.I.

1986-01-01

Zooplankton mortalities resulting from passage through the Donald C. Cook Nuclear Plant (southeastern Lake Michigan) were studied over an 8-year (1975-1982) period. The power plant operated at a low ΔT ( 0 C) and discharge water temperatures did not exceed 35 0 C (except September 1978). While zooplankton mortalities were significantly greater in discharge than intake waters, differences were small, averaging <3%. There was no evidence of additional delayed effects on zooplankton mortality following plant passage. There was no relationship between zooplankton mortalities and temperature (ΔT, discharge water temperature). Mechanical stresses appeared to be the major cause of zooplankton mortality. The authors hypothesize that fish predation, rather than power plant operation, probably was the major source of zooplankton mortality in inshore waters during much of the year. (author)

Nocturnality constrains morphological and functional diversity in the eyes of reef fishes

Directory of Open Access Journals (Sweden)

Schmitz Lars

2011-11-01

Full Text Available Abstract Background Ambient light levels are often considered to drive the evolution of eye form and function. Diel activity pattern is the main mechanism controlling the visual environment of teleost reef fish, with day-active (diurnal fish active in well-illuminated conditions, whereas night-active (nocturnal fish cope with dim light. Physiological optics predicts several specific evolutionary responses to dim-light vision that should be reflected in visual performance features of the eye. Results We analyzed a large comparative dataset on morphological traits of the eyes in 265 species of teleost reef fish in 43 different families. The eye morphology of nocturnal reef teleosts is characterized by a syndrome that indicates better light sensitivity, including large relative eye size, high optical ratio and large, rounded pupils. Improved dim-light image formation comes at the cost of reduced depth of focus and reduction of potential accommodative lens movement. Diurnal teleost reef fish, released from the stringent functional requirements of dim-light vision have much higher morphological and optical diversity than nocturnal species, with large ranges of optical ratio, depth of focus, and lens accommodation. Conclusions Physical characteristics of the environment are an important factor in the evolution and diversification of the vertebrate eye. Both teleost reef fish and terrestrial amniotes meet the functional requirements of dim-light vision with a similar evolutionary response of morphological and optical modifications. The trade-off between improved dim-light vision and reduced optical diversity may be a key factor in explaining the lower trophic diversity of nocturnal reef teleosts.

Evaluation of swimming capability and potential velocity barrier problems for fish. Part B: New telemetric approaches to the assessment of fish swimming performance

International Nuclear Information System (INIS)

Scruton, D. A.; Goosney, R. G.; McKinley, R. S.; Booth, R. K.; Colavecchia, M.

1998-08-01

This report represents the second part of a study undertaken to develop information related to swimming capability of several important fish species. The study will provide biological design criteria to mitigate potential velocity barrier problems associated with hydroelectric power plants. This part of the report focuses on the development and evaluation of approaches to assessing locomotory activity, swimming performance and energy load costs to fish under naturally occurring conditions and in relation to potential barriers. The study involved implantation of a bio-sensitive radio transmitter (electromyogram (EMG)) tag in the swimming muscle of fish, calibration of locomotory ability and energetic scope, and subsequent use of EMG signals to assess swimming performance and metabolic costs in situ. Digital signal processing (DSP) with antennae switching was also used to study high speed swimming performance, behaviour, and migratory strategy in relation to ascent of an experimental flume. The techniques and technologies developed indicate the complexity of factors that regulate fish swimming energy expenditure that need to be considered in the design and operation of fish passage facilities. 84 refs., 6 tabs., figs., 2 appendices

Reasonable Accommodation Information Tracking System

Data.gov (United States)

U.S. Environmental Protection Agency — The Reasonable Accommodation Information Tracking System (RAITS) is a case management system that allows the National Reasonable Accommodation Coordinator (NRAC) and...

Analysis of Environmental Issues Related to Small-Scale Hydroelectric Development II: Design Consideration for Passing Fish Upstream Around Dams

Energy Technology Data Exchange (ETDEWEB)

Hildebrandt, S. G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bell, M. C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Anderson, J. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Richey, E. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Parkhurst, Z. E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

1980-08-01

The purpose of this report is to provide general information for use by potential developers of small scale hydroelectric projects that will include facilities to pass migrating fish upstream around dams. The document is not intended to be a textbook on design of fish passage facilities, but rather to be a general guide to some factors that are important when designing such facilities.

Nonverbal accommodation in health care communication.

Science.gov (United States)

D'Agostino, Thomas A; Bylund, Carma L

2014-01-01

This exploratory study examined patterns of nonverbal accommodation within health care interactions and investigated the impact of communication skills training and gender concordance on nonverbal accommodation behavior. The Nonverbal Accommodation Analysis System (NAAS) was used to code the nonverbal behavior of physicians and patients within 45 oncology consultations. Cases were then placed in one of seven categories based on patterns of accommodation observed across the interaction. Results indicated that across all NAAS behavior categories, physician-patient interactions were most frequently categorized as joint convergence, followed closely by asymmetrical-patient convergence. Among paraverbal behaviors, talk time, interruption, and pausing were most frequently characterized by joint convergence. Among nonverbal behaviors, eye contact, laughing, and gesturing were most frequently categorized as asymmetrical-physician convergence. Differences were predominantly nonsignificant in terms of accommodation behavior between pre- and post-communication skills training interactions. Only gesturing proved significant, with post-communication skills training interactions more likely to be categorized as joint convergence or asymmetrical-physician convergence. No differences in accommodation were noted between gender-concordant and nonconcordant interactions. The importance of accommodation behavior in health care communication is considered from a patient-centered care perspective.

Soyasaponins resist extrusion cooking and are not degraded during gut passage in Atlantic salmon (Salmo salar L.)

DEFF Research Database (Denmark)

Knudsen, Sven David Lausten; Røn, Ø.; Baardsen, G.

2006-01-01

The stability of soyasaponins in fish feed formulations was investigated. The level of soyasaponin Ab, Bb, Bc, Ba-2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one (Ba-DDMP), Bb-DDMP, and BcDDMP was quantified in 15 samples of defatted soybean meal, two full fat soybean meals, and two soybean pro....... The present work demonstrates that non-DDMP-conjugated group B soyasaponins resist extrusion cooking and remain intact during gut passage in Atlantic salmon. The latter is contrary to earlier findings in endothermic animals....

Effect of heterophoria measurement technique on the clinical accommodative convergence to accommodation ratio.

Science.gov (United States)

Escalante, Jaime Bernal; Rosenfield, Mark

2006-05-01

Measurement of the stimulus accommodative convergence to accommodation (AC/A) ratio is a standard procedure in clinical optometric practice. Typically, heterophoria is assessed at several accommodative stimulus levels, and the gradient of the vergence to accommodation function computed. A number of procedures are available for the subjective measurement of heterophoria, but it is unclear whether the use of different vergence measurement techniques will alter the obtained AC/A value. Accordingly, the current study compared AC/A ratios measured using 3 clinical subjective heterophoria tests, namely the von Graefe (VG), Maddox Rod (MR), and Modified Thorington (MT) procedures. The AC/A ratio was measured in 60 visually normal subjects between 20 and 25 years of age using each of the 3 procedures listed above. The accommodative stimulus was varied by the introduction of +/-1.00 diopter (D) spherical lenses over the distance refractive correction while subjects viewed a target at a viewing distance of 40 cm. To examine the repeatability of each procedure, the AC/A ratio was measured on 2 separate occasions for each measurement technique, with the 2 sessions being separated by at least 24 hours. Mean values of stimulus AC/A ratio measured using the VG, MR, and MT procedures were 3.47, 2.99, and 2.46Delta/D, respectively. These differences were significant (p=0.0001). In addition, the coefficient of repeatability for the 3 techniques was 2.22, 1.99, and 1.20 Delta/D, respectively. Ratios obtained using the Modified Thorington technique with +/-1.00 D lenses showed the best repeatability, whereas the poorest repeatability was found with the von Graefe technique when only +1.00 D lenses were used to vary the accommodative stimulus. Accordingly, we recommend that that Modified Thorington procedure with +/-1.00 D lenses be used to quantify heterophoria during clinical measurement of the stimulus AC/A ratio.

Skeptical notes on a physics of passage.

Science.gov (United States)

Huggett, Nick

2014-10-01

This paper investigates the mathematical representation of time in physics. In existing theories, time is represented by the real numbers, hence their formal properties represent properties of time: these are surveyed. The central question of the paper is whether the existing representation of time is adequate, or whether it can or should be supplemented: especially, do we need a physics incorporating some kind of "dynamical passage" of time? The paper argues that the existing mathematical framework is resistant to such changes, and might have to be rejected by anyone seeking a physics of passage. Then it rebuts two common arguments for incorporating passage into physics, especially the claim that it is an element of experience. Finally, the paper investigates whether, as has been claimed, causal set theory provides a physics of passage. © 2014 New York Academy of Sciences.

A review of non-strabismic accommodative and vergence anomalies in school-age children. Part 2: Accommodative anomalies

Directory of Open Access Journals (Sweden)

Samuel O. Wajuihian

2015-08-01

Full Text Available Comfortable reading and the performance of related near point activities involve efficient accommodative and vergence systems. However, accommodative and convergence anomalies are associated with various symptoms of asthenopia that impair efficient near point tasks. In Part 1 of this two-part article, studies on vergence anomalies were reviewed. In the current paper (Part 2, anomalies of accommodation are reviewed. The aims of the latter paper were to derive the prevalence and distribution estimates of anomalies of accommodation in school-age children and address variations in the study methods and findings. Despite variations in the study methods and findings, anomalies of accommodation are prevalent among school-age populations. Variations and limitations of previous studies are discussed and recommendations for improving future studies are suggested.

46 CFR 108.143 - Accommodation space.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Accommodation space. 108.143 Section 108.143 Shipping... EQUIPMENT Construction and Arrangement Structural Fire Protection § 108.143 Accommodation space. (a) Each corridor bulkhead in an accommodation space must be an A class or B class bulkhead except if an A class...

Evaluating the effectiveness of restoring longitudinal connectivity for stream fish communities: towards a more holistic approach.

Science.gov (United States)

Tummers, Jeroen S; Hudson, Steve; Lucas, Martyn C

2016-11-01

A more holistic approach towards testing longitudinal connectivity restoration is needed in order to establish that intended ecological functions of such restoration are achieved. We illustrate the use of a multi-method scheme to evaluate the effectiveness of 'nature-like' connectivity restoration for stream fish communities in the River Deerness, NE England. Electric-fishing, capture-mark-recapture, PIT telemetry and radio-telemetry were used to measure fish community composition, dispersal, fishway efficiency and upstream migration respectively. For measuring passage and dispersal, our rationale was to evaluate a wide size range of strong swimmers (exemplified by brown trout Salmo trutta) and weak swimmers (exemplified by bullhead Cottus perifretum) in situ in the stream ecosystem. Radio-tracking of adult trout during the spawning migration showed that passage efficiency at each of five connectivity-restored sites was 81.3-100%. Unaltered (experimental control) structures on the migration route had a bottle-neck effect on upstream migration, especially during low flows. However, even during low flows, displaced PIT tagged juvenile trout (total n=153) exhibited a passage efficiency of 70.1-93.1% at two nature-like passes. In mark-recapture experiments juvenile brown trout and bullhead tagged (total n=5303) succeeded in dispersing upstream more often at most structures following obstacle modification, but not at the two control sites, based on a Laplace kernel modelling approach of observed dispersal distance and barrier traverses. Medium-term post-restoration data (2-3years) showed that the fish assemblage remained similar at five of six connectivity-restored sites and two control sites, but at one connectivity-restored headwater site previously inhabited by trout only, three native non-salmonid species colonized. We conclude that stream habitat reconnection should support free movement of a wide range of species and life stages, wherever retention of such

Critical behavior of the two-dimensional first passage time

International Nuclear Information System (INIS)

Chayes, J.T.; Chayes, L.; Durrett, R.

1986-01-01

We study the two-dimensional first passage problem in which bonds have zero and unit passage times with probability p and 1-p, respectively. We provide that as the zero-time bonds approach the percolation threshold p/sub c/, the first passage time exhibits the same critical behavior as the correlation function of the underlying percolation problem. In particular, if the correlation length obeys ξ(p)--chemical bondp-p/sub c/chemical bond/sup -//sup v/, then the first passage time constant satisfies μ(p)--chemical bondp-p/sub c/chemical bond/sup v/. At p/sub c/, where it has been asserted that the first passage time from 0 to x scales as chemical bondxchemical bond to a power psi with 0< psi<1, we show that the passage times grow like log chemical bondxchemical bond, i.e., the fluid spreads exponentially rapidly

Columbia River Basin Fish and Wildlife Program Work Plan for Fiscal Year 1988.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration; Northwest Power Planning Council (U.S.); Columbia Basin Fish and Wildlife Authority

1987-10-01

The FY 1988 Columbia River Basin Fish and Wildlife Program Work Plan (Work Plan) presents Bonneville Power Administration's plans for implementing the Columbia River Basin Fish and Wildlife Program (Program) in FY 1988. The Work Plan focuses on individual Action Items found in the amended Program for which Bonneville Power Administration (BPA) has determined it has authority and responsibility to implement. The FY 1988 Work Plan emphasizes continuation of 95 ongoing projects, most of which involve protection, mitigation, or enhancement of anadromous fishery resources. These continuing activities are summarized briefly by Program area: (1) mainstem passage; (2) artificial propagation; (3) natural propagation; (4) resident fish and wildlife; and (5) planning activities.

Navigable windows of the Northwest Passage

Science.gov (United States)

Liu, Xing-he; Ma, Long; Wang, Jia-yue; Wang, Ye; Wang, Li-na

2017-09-01

Artic sea ice loss trends support a greater potential for Arctic shipping. The information of sea ice conditions is important for utilizing Arctic passages. Based on the shipping routes given by ;Arctic Marine Shipping Assessment 2009 Report;, the navigable windows of these routes and the constituent legs were calculated by using sea ice concentration product data from 2006 to 2015, by which a comprehensive knowledge of the sea ice condition of the Northwest Passage was achieved. The results showed that Route 4 (Lancaster Sound - Barrow Strait - Prince Regent Inlet and Bellot Strait - Franklin Strait - Larsen Sound - Victoria Strait - Queen Maud Gulf - Dease Strait - Coronation Gulf - Dolphin and Union Strait - Amundsen Gulf) had the best navigable expectation, Route 2 (Parry Channel - M'Clure Strait) had the worst, and the critical legs affecting the navigation of Northwest Passage were Viscount Melville Sound, Franklin Strait, Victoria Strait, Bellot Strait, M'Clure Strait and Prince of Wales Strait. The shortest navigable period of the routes of Northwest Passage was up to 69 days. The methods used and the results of the study can help the selection and evaluation of Arctic commercial routes.

Accommodation, accommodative convergence, and response AC/A ratios before and at the onset of myopia in children.

Science.gov (United States)

Gwiazda, Jane; Thorn, Frank; Held, Richard

2005-04-01

The purpose of this study was to investigate accommodation, accommodative convergence, and AC/A ratios before and at the onset of myopia in children. Refractive error, accommodation, and phorias were measured annually over a period of 3 years in 80 6- to 18-year-old children (mean age at first visit = 11.1 years), including 26 who acquired myopia of at least -0.50 D and 54 who remained emmetropic (-0.25 to + 0.75 D). Refraction was measured by noncycloplegic distance retinoscopy. Concomitant measures of accommodation and phorias were taken for letter targets at 4.0 m and 0.33 m using the Canon R-1 open field-of-view autorefractor with an attached motorized Risley prism and Maddox rod. The accommodation and phoria measurements were used to calculate response AC/A ratios. Compared with children who remained emmetropic, those who became myopic had elevated response AC/A ratios at 1 and 2 years before the onset of myopia, in addition to at onset and 1 year later (t's = -2.97 to -4.04, p accommodation. Accommodative convergence was significantly greater in myopes only at onset. These findings suggest that the abnormal oculomotor factors found before the onset of myopia may contribute to myopigenesis by producing hyperopic retinal defocus when a child is engaged in near-viewing tasks.

Fishing activities

Science.gov (United States)

Oberle, Ferdinand; Puig, Pere; Martin, Jacobo; Micallef, Aaron; Krastel, Sebastian; Savini, Alessandra

2018-01-01

Unlike the major anthropogenic changes that terrestrial and coastal habitats underwent during the last centuries such as deforestation, river engineering, agricultural practices or urbanism, those occurring underwater are veiled from our eyes and have continued nearly unnoticed. Only recent advances in remote sensing and deep marine sampling technologies have revealed the extent and magnitude of the anthropogenic impacts to the seafloor. In particular, bottom trawling, a fishing technique consisting of dragging a net and fishing gear over the seafloor to capture bottom-dwelling living resources has gained attention among the scientific community, policy makers and the general public due to its destructive effects on the seabed. Trawling gear produces acute impacts on biota and the physical substratum of the seafloor by disrupting the sediment column structure, overturning boulders, resuspending sediments and imprinting deep scars on muddy bottoms. Also, the repetitive passage of trawling gear over the same areas creates long-lasting, cumulative impacts that modify the cohesiveness and texture of sediments. It can be asserted nowadays that due to its recurrence, mobility and wide geographical extent, industrial trawling has become a major force driving seafloor change and affecting not only its physical integrity on short spatial scales but also imprinting measurable modifications to the geomorphology of entire continental margins.

Passage Distribution and Federal Columbia River Power System Survival for Steelhead Kelts Tagged Above and at Lower Granite Dam, Year 2

Energy Technology Data Exchange (ETDEWEB)

Colotelo, Alison HA; Harnish, Ryan A.; Jones, Bryan W.; Hanson, Amanda C.; Trott, Donna M.; Greiner, Michael J.; McMichael, Geoffrey A.; Ham, Kenneth D.; Deng, Zhiqun; Brown, Richard S.; Weiland, Mark A.; Li, X.; Fu, Tao

2014-03-28

Steelhead (Oncorhynchus mykiss) populations have declined throughout their range in the last century and many populations, including those of the Snake River Basin are listed under the Endangered Species Act of 1973. The reasons for their decline are many and complex, but include habitat loss and degradation, overharvesting, and dam construction. The 2008 Biological Opinion calls for an increase in the abundance of female steelhead through an increase in iteroparity (i.e., repeat spawning) and this can be realized through a combination of reconditioning and in-river survival of migrating kelts. The goal of this study is to provide the data necessary to inform fisheries managers and dam operators of Snake River kelt migration patterns, survival, and routes of dam passage. Steelhead kelts (n = 487) were captured and implanted with acoustic transmitters and passive integrated transponder (PIT)-tags at the Lower Granite Dam (LGR) Juvenile Fish Facility and at weirs located in tributaries of the Snake and Clearwater rivers upstream of LGR. Kelts were monitored as they moved downstream through the Federal Columbia River Power System (FCRPS) by 15 autonomous and 3 cabled acoustic receiver arrays. Cabled receiver arrays deployed on the dam faces allowed for three-dimensional tracking of fish as they approached the dam face and were used to determine the route of dam passage. Overall, 27.3% of the kelts tagged in this study successfully migrated to Martin Bluff (rkm 126, as measured from the mouth of the Columbia River), which is located downstream of all FCRPS dams. Within individual river reaches, survival per kilometer estimates ranged from 0.958 to 0.999; the lowest estimates were observed in the immediate forebay of FCRPS dams. Steelhead kelts tagged in this study passed over the spillway routes (spillway weirs, traditional spill bays) in greater proportions and survived at higher rates compared to the few fish passed through powerhouse routes (turbines and juvenile

Passage Distribution and Federal Columbia River Power System Survival for Steelhead Kelts Tagged Above and at Lower Granite Dam, Year 2

Energy Technology Data Exchange (ETDEWEB)

Colotelo, Alison H.A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Harnish, Ryan A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Bryan W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hanson, Amanda C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Trott, Donna M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Greiner, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mcmichael, Geoffrey A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ham, Kenneth D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Deng, Zhiqun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Brown, Richard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Li, Xinya [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fu, Tao [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2014-12-15

Steelhead (Oncorhynchus mykiss) populations have declined throughout their range in the last century and many populations, including those of the Snake River Basin are listed under the Endangered Species Act of 1973. The reasons for their decline are many and complex, but include habitat loss and degradation, overharvesting, and dam construction. The 2008 Biological Opinion calls for an increase in the abundance of female steelhead through an increase in iteroparity (i.e., repeat spawning) and this can be realized through a combination of reconditioning and in-river survival of migrating kelts. The goal of this study is to provide the data necessary to inform fisheries managers and dam operators of Snake River kelt migration patterns, survival, and routes of dam passage. Steelhead kelts (n = 487) were captured and implanted with acoustic transmitters and passive integrated transponder (PIT)-tags at the Lower Granite Dam (LGR) Juvenile Fish Facility and at weirs located in tributaries of the Snake and Clearwater rivers upstream of LGR. Kelts were monitored as they moved downstream through the Federal Columbia River Power System (FCRPS) by 15 autonomous and 3 cabled acoustic receiver arrays. Cabled receiver arrays deployed on the dam faces allowed for three-dimensional tracking of fish as they approached the dam face and were used to determine the route of dam passage. Overall, 27.3% of the kelts tagged in this study successfully migrated to Martin Bluff (rkm 126, as measured from the mouth of the Columbia River), which is located downstream of all FCRPS dams. Within individual river reaches, survival per kilometer estimates ranged from 0.958 to 0.999; the lowest estimates were observed in the immediate forebay of FCRPS dams. Steelhead kelts tagged in this study passed over the spillway routes (spillway weirs, traditional spill bays) in greater proportions and survived at higher rates compared to the few fish passed through powerhouse routes (turbines and juvenile

Laboratory studies on the effects of shear on fish: Final report

Energy Technology Data Exchange (ETDEWEB)

Neitzel, Duane A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Richmond, M. C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dauble, D. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mueller, R. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Moursund, R. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Abernethy, C. S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Guensch, G. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cada, G. F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2000-09-01

The overall objective of these studies was to specify an index describing the hydraulic force that fish experience when subjected to a shear environment. Fluid shear is a phenomenon that is important to fish. However, elevated levels of shear may result in strain rates that injure or kill fish. At hydroelectric generating facilities, concerns have been expressed that strain rates associated with passage through turbines, spillways, and fish bypass systems may adversely affect migrating fish. Development of fish-friendly hydroelectric turbines requires knowledge of the physical forces (injury mechanisms) that impact entrained fish and the fish’s tolerance to these forces. It requires up-front, pre-design specifications for the environmental conditions that occur within the turbine system; in other words, determining or assuming conditions known to injure fish will assist engineers in the design of a fish-friendly turbine system. To address the development of biological specifications, this experiment designed and built a test facility where juvenile fish could be subjected to a range of shear environments and quantified their biological response. The test data reported here provide quantified strain rates and the relationship of these forces to direct and indirect biological effects on fish. The study concludes that juvenile salmonids and American shad should survive shear environments where strain rates do not exceed 500 cm/s/cm at a Dy of 1.8 cm. Additional studies are planned with a sensor fish to better link hydraulic conditions found within the laboratory and field environments.

Excess bottom radon 222 distribution in deep ocean passages

International Nuclear Information System (INIS)

Sarmiento, J.L.; Broecker, W.S.; Biscaye, P.E.

1978-01-01

Radon 222 and STD profiles were obtained as part of the Geosecs program in the Vema Channel in the southwest Atlantic Ocean and in the Samoan, Clarion, and Wake Island passages in the Pacific Ocean. The standing crop of excess radon 222 is higher in the passages than at other nearby locations. The most likely explanation for this is that there is a high flux of radon 222 from the floor of the passages. Since much of the floor is covered with manganese nodules and encrustations, the high flux of radon 222 may be attributable to the high concentrations of radium 226 in the outer few millimeters of such deposits. Laboratory measurements of radon 222 emissivity from maganese encrustations obtained in Vema Channel support this hypothesis. The excess radon 222 in the Vema Channel and Wake Island Passage is found in substantial quantities at heights above bottom greatly exceeding the heights at which excess radon 222 is found in nonpassage areas. The horizontal diffusion of radon emanating from the walls of the passages is unlikely to be the cause of the observed concentrations because the ratio of wall surface area to water volume is very low. The profiles must therefore be a result of exceptionally high apparent vertical mixing in the passages. Further work is needed to determine the nature of this apparent vertical mixing. The excess radon 222 and STD data in all four passages have been fit with an empirical model in which it is assumed that the bouyancy flux is constant with distance above bottom. The fits are very good and yield apparent buoyancy fluxes that are between 1 and 3 orders of magnitude greater than those obtained at nearby stations outside the passages for three of the four passages

Forestry practices and aquatic biodiversity: Fish

Science.gov (United States)

Gresswell, Robert E.

2005-01-01

In the Pacific Northwest, fish communities are found in a diverse array of aquatic habitats ranging from the large coastal rivers of the temperate rainforests, to the fragmented and sometimes ephemeral streams of the xeric interior basins, and high-elevation streams and lakes in the mountainous areas (Rieman et al. 2003). Only high-elevation lakes and streams isolated above barriers to fish passage remained historically devoid of fish because they were never invaded following Pleistocene glaciation (Smith 1981). Despite this widespread distribution and once great population abundances, taxonomic diversity of fishes in these forested systems is naturally lower than in aquatic habitats in the eastern U.S. (Reeves, Bisson, and Dambacher 1998). Interactions among factors that influence species richness in aquatic systems (e.g., basin size, long-term stability of habitat, and barriers to colonization; Smith 1981) continue to influence the occurrence and persistence of fishes in these systems today. Consequently, the larger low-elevation rivers and estuaries support the greatest variety of fish species. In the high-elevation tributary streams, fish communities are less complex because these aquatic systems were less climatically and geologically stable, and fish populations were smaller and more prone to local extirpation. Furthermore, barriers to fish passage inhibited dispersal and colonization (Smith 1981). Streams in forested landscapes generally support salmon and trout, Oncorhynchus spp., whitefish Prosopium spp., sculpins Cottus spp., suckers Catostomus spp., and minnows (Cyprinidae), but in some of the colder streams, chars (e.g., Salvelinus confluentus and Salvelinus malma) and lampreys (Petromyzontidae)may also occur (Rieman et al. 2003).Although biodiversity defined in terms of fish species richness is low in the Pacific Northwest, intraspecific variability is high, and polytypic fish species are common in the diverse aquatic habitats of the region. For

A Review of Worksite Lactation Accommodations.

Science.gov (United States)

Hilliard, Elizabeth Dianne

2017-01-01

The purpose of this review was to examine workplace lactation accommodations, and their association with breastfeeding duration, and identify strategies occupational health professionals can use to promote lactation improvements. This study included literature published from 1985 through 2015 and listed in PubMed and CINAHL. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), 11 articles were identified for review. Presence of a corporate lactation program, on-site child care, and return to work/telephone lactation consultation were consistently associated with breastfeeding at 6 months. Other breastfeeding accommodations (i.e., lactation spaces, lactation breaks, worksite lactation policies, and supervisor/coworker support) were not consistently associated with breastfeeding duration. Occupational health professionals can play key roles in improving the effectiveness of lactation accommodations. Assuring adequate implementation of accommodations, increasing communication and marketing of accommodations, and promoting supervisor and coworker support are areas that occupational health professionals should explore for improving lactation duration.

BRANDING ORIENTATION IN THE ACCOMMODATION INDUSTRY

Directory of Open Access Journals (Sweden)

Melissa Li Sa Liow

2015-04-01

Full Text Available This paper starts by clarifying the role of branding orientation (BO among academic studies. It shortly introduces the development of the BO concepts. The empirical part consists of a search for and analysing of academic articles using a meta-analysis that consider BO in the accommodation industry. According to the results, significant appraisal of the branding building activities among higher star rating and luxury accommodation businesses are taking place due to the increasingly demanding guests. Thus, there is an upward pressure on small and medium accommodation businesses to survive or perform well. This paper recommends that scholars study the owners-managers, employees, and customer perspectives altogether, to better comprehend how large accommodation businesses displaying BO can generate superior performance. For the small and medium accommodation businesses, the emphasis is the owners-managers perceptions since they are the main decision-makers, and due to infancy of the small and medium enterprise (SME branding application.

Accommodative spasm in siblings: A unique finding

Directory of Open Access Journals (Sweden)

Rutstein Robert

2010-01-01

Full Text Available Accommodative spasm is a rare condition occurring in children, adolescents, and young adults. A familial tendency for this binocular vision disorder has not been reported. I describe accommodative spasm occurring in a brother and sister. Both children presented on the same day with complaints of headaches and blurred vision. Treatment included cycloplegia drops and bifocals. Siblings of patients having accommodative spasm should receive a detailed eye exam with emphasis on recognition of accommodative spasm.

Accommodative spasm in siblings: A unique finding

Science.gov (United States)

Rutstein, Robert P

2010-01-01

Accommodative spasm is a rare condition occurring in children, adolescents, and young adults. A familial tendency for this binocular vision disorder has not been reported. I describe accommodative spasm occurring in a brother and sister. Both children presented on the same day with complaints of headaches and blurred vision. Treatment included cycloplegia drops and bifocals. Siblings of patients having accommodative spasm should receive a detailed eye exam with emphasis on recognition of accommodative spasm. PMID:20534925

Accommodative Amplitude in School-Age Children

Directory of Open Access Journals (Sweden)

Ikaunieks Gatis

2017-10-01

Full Text Available In children, intensive near-work affects the accommodation system of the eye. Younger children, due to anatomical parameters, read at smaller distance than older children and we can expect that the accommodation system of younger can be affected more than that of older children. We wanted to test this hypothesis. Some authors showed that the norms of amplitude of accommodation (AA developed by Hofstetter (1950 not always could be applied for children. We also wanted to verify these results. A total of 106 (age 7-15 children participated in the study. Distance visual acuity was measured for all children and only data of children with good visual acuity 1.0 or more (dec. units were analysed (73 children. Accommodative amplitude was measured before and after lessons using subjective push-up technique (with RAF Near Point Ruler. The results showed that the amplitude of accommodation reduced significantly (p < 0.05 during the day and decrease of AA was similar in different age groups (about ~0.70 D. Additional measurements are needed to verify that the observed changes in AA were associated with fatigue effect. The results showed lower accommodation values compared to average values calculated according to the Hofstetter equation (p < 0.05.

Effect of Phenylephrine on the Accommodative System

Directory of Open Access Journals (Sweden)

José J. Esteve-Taboada

2016-01-01

Full Text Available Accommodation is controlled by the action of the ciliary muscle and mediated primarily by parasympathetic input through postganglionic fibers that originate from neurons in the ciliary and pterygopalatine ganglia. During accommodation the pupil constricts to increase the depth of focus of the eye and improve retinal image quality. Researchers have traditionally faced the challenge of measuring the accommodative properties of the eye through a small pupil and thus have relied on pharmacological agents to dilate the pupil. Achieving pupil dilation (mydriasis without affecting the accommodative ability of the eye (cycloplegia could be useful in many clinical and research contexts. Phenylephrine hydrochloride (PHCl is a sympathomimetic agent that is used clinically to dilate the pupil. Nevertheless, first investigations suggested some loss of functional accommodation in the human eye after PHCl instillation. Subsequent studies, based on different measurement procedures, obtained contradictory conclusions, causing therefore an unexpected controversy that has been spread almost to the present days. This manuscript reviews and summarizes the main research studies that have been performed to analyze the effect of PHCl on the accommodative system and provides clear conclusions that could help clinicians know the real effects of PHCl on the accommodative system of the human eye.

Development of fish populations in seismostrsss conditions of the south of Russia

Directory of Open Access Journals (Sweden)

P. V. Lyushvin

2009-01-01

Full Text Available The last decades communications between reproduction of many food fishes and traditionally considered factors are lost, is unpredictable time recessions food are observed. The purpose of thepresent work to show, that in the seismo-seas of the south of Russia where there is a unloading litosheric fluids, seismo factors often are defining in reproduction fishes. Earthquakes lead to shortterm unloadings on breaks of an earth's crust through the made active volcanos and griffins of hundreds tons litosheric waters and km³ gases (metane, hydrogen, hydrogen sulphide, radon, etc.. Presence of some of these fluids even in midget concentration (less than 0.1-1 ml/½ causes destruction young fishes, infringement of reproductive functions due to what the food base crabs grows, and after their reproduction and extraction. Landslide reductions of fish populations in current decade it is caused by passage of a maximum of century cyclicity of earthquakes.

Temporary Restoration of Bull Trout Passage at Albeni Falls Dam, 2008 Progress Report.

Energy Technology Data Exchange (ETDEWEB)

Bellgraph, Brian J. [Pacific Northwest National Laboratory

2009-03-31

The goal of this project is to provide temporary upstream passage of bull trout around Albeni Falls Dam on the Pend Oreille River, Idaho. Our specific objectives are to capture fish downstream of Albeni Falls Dam, tag them with combination acoustic and radio transmitters, release them upstream of Albeni Falls Dam, and determine if genetic information on tagged fish can be used to accurately establish where fish are located during the spawning season. In 2007, radio receiving stations were installed at several locations throughout the Pend Oreille River watershed to detect movements of adult bull trout; however, no bull trout were tagged during that year. In 2008, four bull trout were captured downstream of Albeni Falls Dam, implanted with transmitters, and released upstream of the dam at Priest River, Idaho. The most-likely natal tributaries of bull trout assigned using genetic analyses were Grouse Creek (N = 2); a tributary of the Pack River, Lightning Creek (N = 1); and Rattle Creek (N = 1), a tributary of Lightning Creek. All four bull trout migrated upstream from the release site in Priest River, Idaho, were detected at monitoring stations near Dover, Idaho, and were presumed to reside in Lake Pend Oreille from spring until fall 2008. The transmitter of one bull trout with a genetic assignment to Grouse Creek was found in Grouse Creek in October 2008; however, the fish was not found. The bull trout assigned to Rattle Creek was detected in the Clark Fork River downstream from Cabinet Gorge Dam (approximately 13 km from the mouth of Lightning Creek) in September but was not detected entering Lightning Creek. The remaining two bull trout were not detected in 2008 after detection at the Dover receiving stations. This report details the progress by work element in the 2008 statement of work, including data analyses of fish movements, and expands on the information reported in the quarterly Pisces status reports.

Quantum first passage problem

International Nuclear Information System (INIS)

Kumar, N.

1984-07-01

Quantum first passage problem (QUIPP) is formulated and solved in terms of a constrained Feynman path integral. The related paradox of blocking of unitary evolution by continuous observation on the system implicit in QUIPP is briefly discussed. (author)

Ebola virus genome plasticity as a marker of its passaging history: a comparison of in vitro passaging to non-human primate infection.

Directory of Open Access Journals (Sweden)

Jeffrey R Kugelman

Full Text Available To identify polymorphic sites that could be used as biomarkers of Ebola virus passage history, we repeatedly amplified Ebola virus (Kikwit variant in vitro and in vivo and performed deep sequencing analysis of the complete genomes of the viral subpopulations. We then determined the sites undergoing selection during passage in Vero E6 cells. Four locations within the Ebola virus Kikwit genome were identified that together segregate cell culture-passaged virus and virus obtained from infected non-human primates. Three of the identified sites are located within the glycoprotein gene (GP sequence: the poly-U (RNA editing site at position 6925, as well as positions 6677, and 6179. One site was found in the VP24 gene at position 10833. In all cases, in vitro and in vivo, both populations (majority and minority variants were maintained in the viral swarm, with rapid selections occurring after a few passages or infections. This analysis approach will be useful to differentiate whether filovirus stocks with unknown history have been passaged in cell culture and may support filovirus stock standardization for medical countermeasure development.

Privately Provided Accommodation Service Quality and Customer Satisfaction

Directory of Open Access Journals (Sweden)

Joshua Mugambwa

2016-04-01

Full Text Available Privately provided accommodation is a growing service in Uganda’s higher education sector due to education liberalization and demand for education. This research took a case study of Nsamizi Training Institute of Social Development (NTISD to determine the relationship between privately provided accommodation service quality and customer satisfaction. Specifically, the objectives of the study were (a to find out the relationship between security and NTISD students’ satisfaction with privately provided accommodation, and (b to find out the hierarchical level of importance of NTISD student satisfaction of the three service quality dimensions (reliability, security, and tangibles with privately provided accommodation. Using quantitative and qualitative modes of data analysis and a sample of 300 students from 20 private hostels, this study established a strong positive significant relationship between security and satisfaction regarding privately provided accommodation. This implies that accommodation service providers should increase the quality of security so as to increase the satisfaction of students regarding privately provided accommodation. The study established the hierarchical order of importance from the most important service quality dimension, respectively, as follows: reliability, security, and tangibles. Therefore, private accommodation service managers should pay extra attention to the dimensions in the same order.

Six-degree-of-freedom Sensor Fish design - Governing equations and motion modeling

Energy Technology Data Exchange (ETDEWEB)

Zeng, D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Richmond, M. C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Simmons, C. S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carlson, T. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2004-07-01

The Sensor Fish device is being used at Northwest hydropower projects to better understand the conditions fish experience during passage through hydro turbines and other dam bypass alternatives. Since its initial development in 1997, the Sensor Fish has undergone numerous design changes to improve its function and extend the range of its use. The most recent Sensor Fish design, the three degree of freedom (3DOF) device, has been used successfully to characterize the environment fish experience when passing through turbines, in spill, or in engineered fish bypass facilities at dams. Pacific Northwest National Laboratory (PNNL) is in the process of redesigning the current 3DOF Sensor Fish device package to improve its field performance. Rate gyros will be added to the new six degree of freedom (6DOF) device so that it will be possible to observe the six linear and angular accelerations of the Sensor Fish as it passes the dam. Before the 6DOF Sensor Fish device can be developed and deployed, governing equations of motion must be developed in order to understand the design implications of instrument selection and placement within the body of the device. The report describes a fairly general formulation for the coordinate systems, equations of motion, force and moment relationships necessary to simulate the 6DOF movement of an underwater body.

Detection of eyeshine by flashlight fishes of the family Anomalopidae.

Science.gov (United States)

Howland, H C; Murphy, C J; McCosker, J E

1992-04-01

Flashlight fishes of the family Anomalopidae live in clear tropical waters and are nocturnally active. They have luminescent organs located just below the pupils of their eyes. The relation of the luminescent organ to the pupil of the anomalopid eye is similar to that of the illumination and pupil system of the ophthalmoscope and identical to that of some photoretinoscopes. Indeed, one species of flashlight fish, Anomalops katoptron, actually moves its luminous organ away from its pupils in the process of occluding its light organ, making a retinoscopic-like movement. By photographing the eyeshine of a number of fishes with a photoretinoscope and by analyzing the optics of light organs of fish of the family Anomalopidae as well as the optics of reflecting eyes, we show under what light conditions and ranges flashlight fishes may reasonably be able to detect eyeshine from other fishes in the environment. Further, we suggest that flashlight fishes may be able to communicate with each other by altering the accommodation of their eyes. In such a communication system, the sender radiates no energy and communicates only with the interrogating receiver of the information. To our knowledge, this utilization of eyeshine, both for detection and for communication, is unique in the animal kingdom.

Decreased accommodation during decompensation of distance exotropia.

Science.gov (United States)

Horwood, Anna M; Riddell, Patricia M

2012-04-01

Disparity cues can be a major drive to accommodation via the convergence accommodation to convergence (CA/C) linkage, but, on decompensation of exotropia, disparity cues are extinguished by suppression so this drive is lost. This study investigated accommodation and vergence responses to disparity, blur and proximal cues in a group of distance exotropes aged between 4 and 11 years both during decompensation and when exotropic. 19 participants with distance exotropia were tested using a PlusoptiXSO4 photo refractor set in a remote haploscopic device that assessed simultaneous vergence and accommodation to a range of targets incorporating different combinations of blur, disparity and proximal cues at four fixation distances between 2 m and 33 cm. Responses on decompensation were compared with those from the same children when their deviation was controlled. Manifest exotropia was more common in the more impoverished cue conditions. When decompensated for near, mean accommodation gain for the all-cue (naturalistic) target was significantly reduced (paccommodation of 2.33 D at 33 cm. The profile of near cues usage changed after decompensation, with blur and proximity driving residual responses, but these remaining cues did not compensate for loss of accommodation caused by the removal of disparity. Accommodation often reduces on decompensation of distance exotropia as the drive from convergence is extinguished, providing a further reason to try to prevent decompensation for near.

The relativistic titls of Giza pyramids' entrance-passages

Science.gov (United States)

Aboulfotouh, H.

The tilts of Giza pyramids' entrance-passages have never been considered as if they were the result of relativistic mathematical equations, and never been thought to encode the Earth's obliquity parameters. This paper presents an attempt to retrieve the method of establishing the equations that the pyramids' designer used to quantify the entrance-passages' tilts of these architectonic masterpieces. It proves that the pyramids' designer was able to include the geographic, astronomical and time parameters in one relativistic equation, encoding the date of the design of the Giza pyramids in the tilt of the entrance passage of the great pyramid.

Larval fish data collected during shipboard surveys (NF1001 and NF1002) in 2010 in Vieques Sound, Virgin Passage and surrounding regions.

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — In conjunction with the Vieques Sound and Virgin Passage Transport Study, the USVI larval distribution and supply study completed its fourth research cruise during...

77 FR 38833 - Job Accommodation Network

Science.gov (United States)

2012-06-29

... DEPARTMENT OF LABOR Job Accommodation Network AGENCY: Office of Disability Employment Policy, Department of Labor. Announcement Type: New Notice of Availability of Funds and Solicitation for Grant... cooperative agreement to manage and operate its Job Accommodation Network (JAN), a national technical...

Chromatic aberration, accommodation, and color preference in asthenopia.

Science.gov (United States)

Drew, Stefanie A; Borsting, Eric; Stark, Lawrence R; Chase, Chris

2012-07-01

Asthenopia is a common problem associated with near work and reports suggest that colored lenses or overlays may be applied to reduce symptoms. In this study, we examine the relationship between eyestrain, color preferences, and function of the accommodation and vergence system. Specifically, we examine whether symptomatic observers select colors that reduce accommodative demand based on longitudinal chromatic aberration (LCA). Forty-seven undergraduate students participated in this study. Visual discomfort symptoms were assessed using the Conlon survey. A Mark 2 Intuitive Colorimeter was used to obtain optimal colored light preferences. LCA was modeled using the Chromatic Eye and spectral power density data. A comprehensive evaluation of accommodation and vergence was performed following standard procedures. A significant negative correlation (r = -0.51) was found between eyestrain symptoms and the International Commission on Illumination (CIE) v' axis of colors preferences. Additionally, a significant negative correlation (r = -0.31) was found between eyestrain symptoms and LCA accommodation. Two thirds of the participants in the high discomfort group chose colors that decreased accommodative demand. Accommodative amplitude and vergence facility also correlated with LCA, accounting for 25% of the variance. The color preferences of individuals are systematically influenced by the functioning of their accommodation and vergence systems with increased symptomatology resulting in color selections that reduce LCA accommodative stimulus demand.

Insertable fluid flow passage bridgepiece and method

Science.gov (United States)

Jones, Daniel O.

2000-01-01

A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

Experimental investigations of pupil accommodation factors.

Science.gov (United States)

Lee, Eui Chul; Lee, Ji Woo; Park, Kang Ryoung

2011-08-17

PURPOSE. The contraction and dilation of the iris muscle that controls the amount of light entering the retina causes pupil accommodation. In this study, experiments were performed and two of the three factors that influence pupil accommodation were analyzed: lighting conditions and depth fixations. The psychological benefits were not examined, because they could not be quantified. METHODS. A head-wearable eyeglasses-based, eye-capturing device was designed to measure pupil size. It included a near-infrared (NIR) camera and an NIR light-emitting diode. Twenty-four subjects watched two-dimensional (2D) and three-dimensional (3D) stereoscopic videos of the same content, and the changes in pupil size were measured by using the eye-capturing device and image-processing methods: RESULTS. The pupil size changed with the intensity of the videos and the disparities between the left and right images of a 3D stereoscopic video. There was correlation between the pupil size and average intensity. The pupil diameter could be estimated as being contracted from approximately 5.96 to 4.25 mm as the intensity varied from 0 to 255. Further, from the changes in the depth fixation for the pupil accommodation, it was confirmed that the depth fixation also affected accommodation of pupil size. CONCLUSIONS. It was confirmed that the lighting condition was an even more significant factor in pupil accommodation than was depth fixation (significance ratio: approximately 3.2:1) when watching 3D stereoscopic video. Pupil accommodation was more affected by depth fixation in the real world than was the binocular convergence in the 3D stereoscopic display.

Boundaries, transitions and passages

NARCIS (Netherlands)

Koenderink, Jan; van Doorn, Andrea J.; Pinna, Baingio; Wagemans, Johan

2016-01-01

Many pictures are approximately piecewise uniform quilts. The patches meet in transitional areas that have a vague, ribbon-like geometry. These borders may occasionally get lost and sometimes pick up again, creating a 'passage' that partly blends adjacent patches. This type of structure is widely

Ecotourism and Ecolodge Accommodation

Directory of Open Access Journals (Sweden)

Dragan Bulatović

2017-12-01

Full Text Available In ecotourism, as a specific form of tourism, conscientious individuals and groups participate, who by its influence on nature are trying to reduce effects produced by so called mass tourism. Ecotourism product should be developed on the contemporary tourism trends, with full respect of local specificity which represent commitment in regard to competitive destinations. Existence of receptive factors, such as facilities for accommodation, nutrition, entertainment and recreation, represent one of the basic prerequisites for the development of any ecotourism destination. Ecotourists seek accommodation which is ecologically acceptable, modest but cozy at the same time and provides unique experience in natural surroundings. In accordance with these demands protected areas all around the world offer its visitors high quality Ecolodge facilities, which are fully submerged into nature. During their construction and management strict criteria of protection of the environment are followed with optimal waste and energy management. Montenegro has enviable spacious potential for this kind of accommodation in protected areas, especially in its five national parks, so this form of accommodation has to find its place in the future development of tourism. Designing and construction of ecotourism facilities has to be strategically planned and the fact, that it is not enough just to have attractive location but also specific content it has to offer, has to be respected. Ecolodge facilities should be designed and built in accordance with traditional architecture and surrounding materials, to influence as little as possible on the environment and to use alternative energy sources. In other words, it is necessary to provide sustainability of these facilities.

Laboratory Experiments on the Effects of Blade Strike from Hydrokinetic Energy Technologies on Larval and Juvenile Freshwater Fishes

Energy Technology Data Exchange (ETDEWEB)

Schweizer, Peter E [ORNL; Cada, Glenn F [ORNL; Bevelhimer, Mark S [ORNL

2012-03-01

There is considerable interest in the development of marine and hydrokinetic energy projects in rivers, estuaries, and coastal ocean waters of the United States. Hydrokinetic (HK) technologies convert the energy of moving water in river or tidal currents into electricity, without the impacts of dams and impoundments associated with conventional hydropower or the extraction and combustion of fossil fuels. The Federal Energy Regulatory Commission (FERC) maintains a database that displays the geographical distribution of proposed HK projects in inland and tidal waters (FERC 2012). As of March 2012, 77 preliminary permits had been issued to private developers to study HK projects in inland waters, the development of which would total over 8,000 MW. Most of these projects are proposed for the lower Mississippi River. In addition, the issuance of another 27 preliminary permits for HK projects in inland waters, and 3 preliminary permits for HK tidal projects (totaling over 3,100 MW) were under consideration by FERC. Although numerous HK designs are under development (see DOE 2009 for a description of the technologies and their potential environmental effects), the most commonly proposed current-based projects entail arrays of rotating devices, much like submerged wind turbines, that are positioned in the high-velocity (high energy) river channels. The many diverse HK designs imply a diversity of environmental impacts, but a potential impact common to most is the risk for blade strike to aquatic organisms. In conventional hydropower generation, research on fish passage through reaction turbines at low-head dams suggested that strike and mortality for small fish could be low. As a consequence of the large surface area to mass ratio of small fish, the drag forces in the boundary layer flow at the surface of a rotor blade may pull small fish around the leading edge of a rotor blade without making physical contact (Turnpenny 1998, Turnpenny et al. 2000). Although there is

A prototype splitter apparatus for dividing large catches of small fish

Science.gov (United States)

Stapanian, Martin A.; Edwards, William H.

2012-01-01

Due to financial and time constraints, it is often necessary in fisheries studies to divide large samples of fish and estimate total catch from the subsample. The subsampling procedure may involve potential human biases or may be difficult to perform in rough conditions. We present a prototype gravity-fed splitter apparatus for dividing large samples of small fish (30–100 mm TL). The apparatus features a tapered hopper with a sliding and removable shutter. The apparatus provides a comparatively stable platform for objectively obtaining subsamples, and it can be modified to accommodate different sizes of fish and different sample volumes. The apparatus is easy to build, inexpensive, and convenient to use in the field. To illustrate the performance of the apparatus, we divided three samples (total N = 2,000 fish) composed of four fish species. Our results indicated no significant bias in estimating either the number or proportion of each species from the subsample. Use of this apparatus or a similar apparatus can help to standardize subsampling procedures in large surveys of fish. The apparatus could be used for other applications that require dividing a large amount of material into one or more smaller subsamples.

First passage Brownian functional properties of snowmelt dynamics

Science.gov (United States)

Dubey, Ashutosh; Bandyopadhyay, Malay

2018-04-01

In this paper, we model snow-melt dynamics in terms of a Brownian motion (BM) with purely time dependent drift and difusion and examine its first passage properties by suggesting and examining several Brownian functionals which characterize the lifetime and reactivity of such stochastic processes. We introduce several probability distribution functions (PDFs) associated with such time dependent BMs. For instance, for a BM with initial starting point x0, we derive analytical expressions for : (i) the PDF P(tf|x0) of the first passage time tf which specify the lifetime of such stochastic process, (ii) the PDF P(A|x0) of the area A till the first passage time and it provides us numerous valuable information about the total fresh water availability during melting, (iii) the PDF P(M) associated with the maximum size M of the BM process before the first passage time, and (iv) the joint PDF P(M; tm) of the maximum size M and its occurrence time tm before the first passage time. These P(M) and P(M; tm) are useful in determining the time of maximum fresh water availability and in calculating the total maximum amount of available fresh water. These PDFs are examined for the power law time dependent drift and diffusion which matches quite well with the available data of snowmelt dynamics.

[Comparison study on subjective and objective measurements of the accommodative convergence to accommodation ratio].

Science.gov (United States)

Xu, Jing-jing; Xu, Dan; Huang, Tao; Jiang, Jian; Lü, Fan

2012-05-01

To detect the accommodative convergence to accommodation (AC/A) ratios measured respectively by objective and subjective methods. The differences and its relative factors were explored. Forty young volunteers were measured by eye tracker to get the amount of convergence when fixating at the target at 100 cm, 50 cm, 33 cm and 25 cm and were measured by infrared auto-refractor to get corresponding accommodative responses. AC/A ratio based on these two measurements were compared with the calculated and the gradient AC/A ratio from Von Graefe tests. Mean value of stimulated AC/A ratio measured by eye tracker was higher than the calculated and gradient AC/A ratio by Von Graefe method (P = 0.003, 0.001). There are statistic correlation (r = 0.871, P = 0.000) and difference (P = 0.000) between stimulated AC/A ratio and response AC/A ratios both measured by eye tracker, and the difference trends to be greater with the higher AC/A ratio. The objective AC/A ratio is usually higher than the clinical subjective measurement because of more proximal effect. The response AC/A ratio measured objectively may reveal realistically the mutual effect and relationship between accommodation and convergence and it seems to be more credible to be the monitor parameter on progression of myopia in clinics.

Shining the light on the loss of rheophilic fish habitat in lowland rivers as a forgotten consequence of barriers and its implications for management

DEFF Research Database (Denmark)

Birnie-Gauvin, Kim; Aarestrup, Kim; Riis, Torsten M. O.

2017-01-01

modified by agriculture and other human activities for centuries, leaving management practitioners wondering how much change is acceptable to maintain sustainable fish populations and fisheries practices. 4. With examples from Denmark, this paper attempts to conceptualize the loss in habitat as a result...... of barriers in lowland streams and rivers, and the repercussions that such alterations may have on rheophilic fish populations. Furthermore, the need for management to address habitat loss and its related consequences concurrently with the improvement of fish passage is emphasized...

Algorithms for Brownian first-passage-time estimation

Science.gov (United States)

Adib, Artur B.

2009-09-01

A class of algorithms in discrete space and continuous time for Brownian first-passage-time estimation is considered. A simple algorithm is derived that yields exact mean first-passage times (MFPTs) for linear potentials in one dimension, regardless of the lattice spacing. When applied to nonlinear potentials and/or higher spatial dimensions, numerical evidence suggests that this algorithm yields MFPT estimates that either outperform or rival Langevin-based (discrete time and continuous space) estimates.

Flow in Rotating Serpentine Coolant Passages With Skewed Trip Strips

Science.gov (United States)

Tse, David G.N.; Steuber, Gary

1996-01-01

Laser velocimetry was utilized to map the velocity field in serpentine turbine blade cooling passages with skewed trip strips. The measurements were obtained at Reynolds and Rotation numbers of 25,000 and 0.24 to assess the influence of trips, passage curvature and Coriolis force on the flow field. The interaction of the secondary flows induced by skewed trips with the passage rotation produces a swirling vortex and a corner recirculation zone. With trips skewed at +45 deg, the secondary flows remain unaltered as the cross-flow proceeds from the passage to the turn. However, the flow characteristics at these locations differ when trips are skewed at -45 deg. Changes in the flow structure are expected to augment heat transfer, in agreement with the heat transfer measurements of Johnson, et al. The present results show that trips are skewed at -45 deg in the outward flow passage and trips are skewed at +45 deg in the inward flow passage maximize heat transfer. Details of the present measurements were related to the heat transfer measurements of Johnson, et al. to relate fluid flow and heat transfer measurements.

Long-term follow-up of acute isolated accommodation insufficiency.

Science.gov (United States)

Lee, Jung Jin; Baek, Seung-Hee; Kim, Ungsoo Samuel

2013-04-01

To define the long-term results of accommodation insufficiency and to investigate the correlation between accommodation insufficiency and other factors including near point of convergence (NPC), age, and refractive errors. From January 2008 to December 2009, 11 patients with acute near vision disturbance and remote near point of accommodation (NPA) were evaluated. Full ophthalmologic examinations, including best corrected visual acuity, manifest refraction and prism cover tests were performed. Accommodation ability was measured by NPA using the push-up method. We compared accommodation insufficiency and factors including age, refractive errors and NPC. We also investigated the recovery from loss of accommodation in patients. Mean age of patients was 20 years (range, 9 to 34 years). Five of the 11 patients were female. Mean refractive error was -0.6 diopters (range, -3.5 to +0.25 diopters) and 8 of 11 patients (73%) had emmetropia (+0.50 to -0.50 diopters). No abnormalities were found in brain imaging tests. Refractive errors were not correlated with NPA or NPC (rho = 0.148, p = 0.511; rho = 0.319, p = 0.339; respectively). The correlation between age and NPA was not significant (rho = -395, p = 0.069). However, the correlation between age and NPC was negative (rho = -0.508, p = 0.016). Three of 11 patients were lost to follow-up, and 6 of 8 patients had permanent insufficiency of accommodation. Accommodation insufficiency is most common in emmetropia, however, refractive errors and age are not correlated with accommodation insufficiency. Dysfunction of accommodation can be permanent in the isolated accommodation insufficiency.

Accommodation training in foreign workers.

Science.gov (United States)

Takada, Masumi; Miyao, Masaru; Matsuura, Yasuyuki; Takada, Hiroki

2013-01-01

By relaxing the contracted focus-adjustment muscles around the eyeball, known as the ciliary and extraocular muscles, the degree of pseudomyopia can be reduced. This understanding has led to accommodation training in which a visual target is presented in stereoscopic video clips. However, it has been pointed out that motion sickness can be induced by viewing stereoscopic video clips. In Measurement 1 of the present study, we verified whether the new 3D technology reduced the severity of motion sickness in accordance with stabilometry. We then evaluated the short-term effects of accommodation training using new stereoscopic video clips on foreign workers (11 females) suffering from eye fatigue in Measurement 2. The foreign workers were trained for three days. As a result, visual acuity was statistically improved by continuous accommodation training, which will help promote ciliary muscle stretching.

First-Passage-Time Distribution for Variable-Diffusion Processes

Science.gov (United States)

Barney, Liberty; Gunaratne, Gemunu H.

2017-05-01

First-passage-time distribution, which presents the likelihood of a stock reaching a pre-specified price at a given time, is useful in establishing the value of financial instruments and in designing trading strategies. First-passage-time distribution for Wiener processes has a single peak, while that for stocks exhibits a notable second peak within a trading day. This feature has only been discussed sporadically—often dismissed as due to insufficient/incorrect data or circumvented by conversion to tick time—and to the best of our knowledge has not been explained in terms of the underlying stochastic process. It was shown previously that intra-day variations in the market can be modeled by a stochastic process containing two variable-diffusion processes (Hua et al. in, Physica A 419:221-233, 2015). We show here that the first-passage-time distribution of this two-stage variable-diffusion model does exhibit a behavior similar to the empirical observation. In addition, we find that an extended model incorporating overnight price fluctuations exhibits intra- and inter-day behavior similar to those of empirical first-passage-time distributions.

Improved intake design for downstream migrating fish at hydropower plants

International Nuclear Information System (INIS)

Mih, W.C.

1991-01-01

This paper reports on hydroelectric power projects on the Columbia River which provided low-cost electricity to the Pacific Northwest. However, they are detrimental to anadromous fisheries resources. Anadromous fish are migratory. They begin their life in shallow mountain streams. After several months, they migrate to the ocean, where the fish grow to maturity before their return migration. Remarkably, most anadromous fish return to spawn in their natal streams. At dams, the upstream migration of grown salmon and steelhead is accomplished through fishways. The downstream migration of juveniles remains a serious problem. Juvenile fish follow the water flow during their sea-ward migration. When passing through a turbine, fish can be severely injured due to the sudden pressure drop, high velocity shear zones, and rotating turbine blades. Stunned fish that survive the gauntlet of the turbine are easy prey for sea gulls and squawfish in the tailrace of the powerhouse. Fish mortality per turbine passage is estimated at 15 percent. With nine hydropower projected on the main steam of the Columbia River, their combined mortality is very serious. The historical Columbia River anadromous run of about 12 million fish has declined to 2.5 million in recent years. Modern high-output hydraulic turbines are designed to be placed at a lower elevation to minimize cavitation damage to turbine blades. The modern design trend of deep intake submergence has caused parallel and unsteady vortex flow patterns in the forebay, resulting in a decrease in the guiding efficiency of the screens, such as at Bonneville Second Powerhouse and at Rocky Reach Project

Employment Accommodations for People with Disabilities: Does Gender Really Matter?

Directory of Open Access Journals (Sweden)

Helen P Hartnett

2014-06-01

Full Text Available AbstractThe Americans with Disabilities Act (ADA requires employersto provide reasonable accommodations for any qualified individual with adisability. By examining the ongoing evaluation data from the Job AccommodationNetwork (JAN, this study seeks to investigate whether or not genderdifferences are present in the reasonable accommodation process. Open andclosed-ended data are collected using a 20-minute structured telephoneinterview of JAN customers (n= 1,247; 44% response rate. The results show veryfew differences between men’s and women’s accommodation request types, whetheror not accommodations were granted, the costs of requested accommodations, andsatisfaction with JAN. A significant difference, however, was found by genderon the effectiveness of the accommodation.  Key Words: Accommodations, Disabilities, Gender, Employment, Social Work Practice

Design of extended length submerged traveling screen and submerged bar screen fish guidance equipment

International Nuclear Information System (INIS)

Bardy, D.; Lindstrom, M.; Fechner, D.

1991-01-01

The hydropower projects on the Snake and lower Columbia Rivers in the Pacific Northwest are unique because these rivers are also the spawning grounds for migratory salmon. The salmon swim upstream from the ocean, lay their eggs, and die. The newly hatched fingerlings must then make their way past the hydroelectric dams to the ocean. Two separate bypass systems are needed, one to pass the adult fish going upstream, and one to pass the fingerlings going downstream. This paper addresses the design considerations for two of the components of the downstream migrant fish passage facilities, the extended Submerged Traveling Screen and Submerged Bar Screen

Phacoemulsification and implantation of an accommodating IOL after PRK.

Science.gov (United States)

Aslanides, loannis M; Plainis, Sotiris; Kumar, Vinod; Ginis, Harilaos

2006-01-01

To present a case of phacoemulsification and implantation of an accommodating intraocular lens (IOL) in a patient with cataract formation after previous refractive surgery. A 50-year-old man, who initially had photorefractive keratectomy to correct moderate myopia, developed a cataract in one eye. He subsequently underwent phacoemulsification and implantation of a 1CU accommodating IOL, as he wished to remain spectacle independent. The patient's distance vision was fully restored. However, accommodative function, which was assessed using subjective and novice objective techniques, was only partially restored. Although the accommodating IOL fully restored the patient's distance vision, accommodative function was only partially restored.

Bearing-Mounting Concept Accommodates Thermal Expansion

Science.gov (United States)

Nespodzany, Robert; Davis, Toren S.

1995-01-01

Pins or splines allow radial expansion without slippage. Design concept for mounting rotary bearing accommodates differential thermal expansion between bearing and any structure(s) to which bearing connected. Prevents buildup of thermal stresses by allowing thermal expansion to occur freely but accommodating expansion in such way not to introduce looseness. Pin-in-slot configuration also maintains concentricity.

Massification of Higher Education and Students' Accommodation ...

African Journals Online (AJOL)

Massification of Higher Education and Students' Accommodation: The ... of students' accommodation at the University of Dar es salaam (UDSM) over the past 50 years. ... and the quality of learning, as well as the quality of students' life.

Adaptability : How to accommodate changing user preferences

NARCIS (Netherlands)

Remoy, H.T.; van der Voordt, D.J.M.

2013-01-01

Purpose: When current accommodation is unsatisfactorily, office organisations consider relocating to new accommodation that optimally facilitate their main processes, supporting image and financial yield. However, due to high vacancy levels, public opinion and governmental awareness oppose new

Providing Aquatic Organism Passage in Vertically Unstable Streams

Directory of Open Access Journals (Sweden)

JanineM Castro

2016-04-01

Full Text Available Aquatic organism passage barriers have been identified as one of the key impediments to recovery of salmonids and other migratory aquatic organisms in the Pacific Northwest of the United States. As such, state and federal agencies invest millions of dollars annually to address passage barriers. Because many barriers function as ad hoc grade control structures, their removal and/or replacement can unwittingly set off a cascade of effects that can negatively impact the very habitat and passage that project proponents seek to improve. The resultant vertical instability can result in a suite of effects that range from floodplain disconnection and loss of backwater and side channel habitat, to increased levels of turbidity. Risk assessment, including an evaluation of both the stage of stream evolution and a longitudinal profile analysis, provides a framework for determining if grade control is warranted, and if so, what type of structure is most geomorphically appropriate. Potential structures include placement of large wood and roughness elements, and constructed riffles, step-pools, and cascades. The use of structure types that mimic natural reach scale geomorphic analogues should result in improved aquatic organism passage, increased structural resilience, and reduced maintenance.

Teleportation of an Unknown Atomic State via Adiabatic Passage

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

We propose a scheme for teleporting an unknown atomic state via adiabatic passage. Taking advantage of adiabatic passage, the atom has no probability of being excited and thus the atomic spontaneous emission is suppressed.We also show that the fidelity can reach 1 under certain condition.

First passage time probability in risk analysis

International Nuclear Information System (INIS)

Karmeshu; Ariaratnam, S.T.

1982-01-01

Many natural phenomena are subject to uncertain fluctuations due to a variety of internal or external factors. These phenomena can be described using stochastic models. An important quantity of interest involves the time lapse before some variables reach unacceptable values: the first passage time. A related question pertains to the statistical distributions of the extreme values of these variables in a given period of time. The authors discuss some problems drawn from population ecology and environmental engineering to illustrate the usefulness of the first passage time concept

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

Science.gov (United States)

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.

Field-based evaluations of horizontal flat-plate fish screens, II: Testing of a unique off-stream channel device - The Farmers Screen

Science.gov (United States)

Mesa, Matthew G.; Rose, Brien P.; Copeland, Elizabeth S.

2012-01-01

Screens are installed at water diversion sites to reduce entrainment of fish. Recently, the Farmers Irrigation District (Oregon) developed a unique flat-plate screen (the “Farmers Screen”) that operates passively and may offer reduced installation and operating costs. To evaluate the effectiveness of this screen on fish, we conducted two separate field experiments. First, juvenile coho salmon Oncorhynchus kisutch were released over a working version of this screen under a range of inflows (0.02–0.42 m3/s) and diversion flows (0.02–0.34 m3/s) at different water depths. Mean approach velocities ranged from 0 to 5 cm/s and sweeping velocities ranged from 36 to 178 cm/s. Water depths over the screen surface ranged from 1 to 25 cm and were directly related to inflow. Passage of fish over the screen under these conditions did not severely injure them or cause delayed mortality, and no fish were observed becoming impinged on the screen surface. Second, juvenile coho salmon and steelhead O. mykiss were released at the upstream end of a 34-m flume and allowed to volitionally move downstream and pass over a 3.5-m section of the Farmers Screen to determine whether fish would refuse to pass over the screen after encountering its leading edge. For coho salmon, 75–95% of the fish passed over the screen within 5 min and 82–98% passed within 20 min, depending on hydraulic conditions. For steelhead, 47–90% of the fish passed over the screen within 5 min and 79–95% passed within 20 min. Our results indicate that when operated within its design criteria, the Farmers Screen provides safe and efficient downstream passage of juvenile salmonids under a variety of hydraulic conditions.

Upstream passage, spawning, and stock identification of fall chinook in the Snake River, 1992 and 1993. Final report

International Nuclear Information System (INIS)

Blankenship, H.L.; Mendel, G.W.

1997-05-01

This final report of the 3-year study summarizes activities and results for 1993. Study objectives were to: (1) determine the source of losses (or accounting errors) for adult chinook salmon between Ice Harbor Dam (IHR) and Lower Granite Dam (LGR), and upstream of LGR in the Snake River; (2) identify spawning locations upstream of LGR for calibration of aerial redd surveys, redd habitat mapping, carcass recovery for genetic stock profile analysis, and correction of estimated adult/redd ratios; and (3) estimate passage and migration times at Snake River. 200 fall chinook salmon were radio tagged and tracked with aerial, fixed-site, and ground mobile tracking. Fish were released upstream of IHR at Charbonneau Park (CHAR). 190 of the fish were tracked or relocated away from CHAR. 59 fish descended to below IHR without crossing Lower Monumental Dam (LMO). Another 128 salmon passed upstream of LMO without falling back at IHR. Only 80 salmon passed Little Goose Dam (LGO) without falling back at a downstream dam; 66 of these fish passed LGR. Many fish that fell back reascended the dams. A total of 72 salmon released at CHAR passed upstream of LGR, including fish that had fallen back and reascended a dam. Over 80 percent of the salmon that entered Lyons Ferry Hatchery each year had reached LGO before descending to the hatchery. Extensive wandering was documented between LMO and upstream of LGR before salmon entered Lyons Ferry Hatchery or the Tucannon River. In 1993, 41 salmon were found to be of hatchery origin when recovered. These fish entered Lyons Ferry Hatchery with similar movements to unmarked salmon. Each year a few salmon have remained near the hatchery without entering, which suggests the hatchery may have inadequate attraction flows. Fall chinook passed lower Snake River dams in 2-5 days each on average. Median travel times through LMO and LGO were 1.0-1.3 days each, which was slower than for spring chinook or steelhead in 1993. 5 refs., 21 figs., 20 tabs

Fish length, water temperature, conductivity, and dissolved oxygen data collected from Strawberry Creek, Redwood National Park, California from 2012-02-12 to 2016-02-25 (NCEI Accession 0148460)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — There have been several recent efforts to restore Strawberry Creek including reed canary grass removal, riparian plantings, increasing fish passage at the County...

Physical passaging of embryoid bodies generated from human pluripotent stem cells.

Directory of Open Access Journals (Sweden)

Mi-Young Son

Full Text Available Spherical three-dimensional cell aggregates called embryoid bodies (EBs, have been widely used in in vitro differentiation protocols for human pluripotent stem cells including human embryonic stem cells (hESCs and human induced pluripotent stem cells (hiPSCs. Recent studies highlight the new devices and techniques for hEB formation and expansion, but are not involved in the passaging or subculture process. Here, we provide evidence that a simple periodic passaging markedly improved hEB culture condition and thus allowed the size-controlled, mass production of human embryoid bodies (hEBs derived from both hESCs and hiPSCs. hEBs maintained in prolonged suspension culture without passaging (>2 weeks showed a progressive decrease in the cell growth and proliferation and increase in the apoptosis compared to 7-day-old hEBs. However, when serially passaged in suspension, hEB cell populations were significantly increased in number while maintaining the normal rates of cell proliferation and apoptosis and the differentiation potential. Uniform-sized hEBs produced by manual passaging using a 1∶4 split ratio have been successfully maintained for over 20 continuous passages. The passaging culture method of hEBs, which is simple, readily expandable, and reproducible, could be a powerful tool for improving a robust and scalable in vitro differentiation system of human pluripotent stem cells.

Extended passaging increases the efficiency of neural differentiation from induced pluripotent stem cells

Directory of Open Access Journals (Sweden)

Koehler Karl R

2011-08-01

Full Text Available Abstract Background The use of induced pluripotent stem cells (iPSCs for the functional replacement of damaged neurons and in vitro disease modeling is of great clinical relevance. Unfortunately, the capacity of iPSC lines to differentiate into neurons is highly variable, prompting the need for a reliable means of assessing the differentiation capacity of newly derived iPSC cell lines. Extended passaging is emerging as a method of ensuring faithful reprogramming. We adapted an established and efficient embryonic stem cell (ESC neural induction protocol to test whether iPSCs (1 have the competence to give rise to functional neurons with similar efficiency as ESCs and (2 whether the extent of neural differentiation could be altered or enhanced by increased passaging. Results Our gene expression and morphological analyses revealed that neural conversion was temporally delayed in iPSC lines and some iPSC lines did not properly form embryoid bodies during the first stage of differentiation. Notably, these deficits were corrected by continual passaging in an iPSC clone. iPSCs with greater than 20 passages (late-passage iPSCs expressed higher expression levels of pluripotency markers and formed larger embryoid bodies than iPSCs with fewer than 10 passages (early-passage iPSCs. Moreover, late-passage iPSCs started to express neural marker genes sooner than early-passage iPSCs after the initiation of neural induction. Furthermore, late-passage iPSC-derived neurons exhibited notably greater excitability and larger voltage-gated currents than early-passage iPSC-derived neurons, although these cells were morphologically indistinguishable. Conclusions These findings strongly suggest that the efficiency neuronal conversion depends on the complete reprogramming of iPSCs via extensive passaging.

Family accommodation in adult obsessive–compulsive disorder: clinical perspectives

Directory of Open Access Journals (Sweden)

Albert U

2017-09-01

Full Text Available Umberto Albert, Alessandra Baffa, Giuseppe Maina Rita Levi Montalcini Department of Neuroscience, A.O.U. San Luigi Gonzaga, University of Turin, Turino, Italy Abstract: The term accommodation has been used to refer to family responses specifically related to obsessive–compulsive (OC symptoms: it encompasses behaviors such as directly participating in compulsions, assisting a relative with obsessive–compulsive disorder (OCD when he/she is performing a ritual, or helping him/her to avoid triggers that may precipitate obsessions and compulsions. At the opposite side, family responses to OCD may also include interfering with the rituals or actively opposing them; stopping accommodating OC symptoms or actively interfering with their performance is usually associated with greater distress and sometimes even with aggressive behaviors from the patients. This article summarizes progress of the recent research concerning family accommodation in relatives of patients with OCD. Family accommodation is a prevalent phenomenon both among parents of children/adolescents with OCD and relatives/caregivers of adult patients. It can be measured with a specific instrument, the Family Accommodation Scale, of which there are several versions available for use in clinical practice. The vast majority of both parents of children/adolescents with OCD and family members of adult patients show at least some accommodation; providing reassurances to obsessive doubts, participating in rituals and assisting the patient in avoidance are the most frequent accommodating behaviors displayed by family members. Modification of routine and modification of activities specifically due to OC symptoms have been found to be equally prevalent. Specific characteristics of patients (such as contamination/washing symptoms and of relatives (the presence of anxiety or depressive symptoms or a family history positive for another anxiety disorder are associated with a higher degree of family

28 CFR 36.310 - Transportation provided by public accommodations.

Science.gov (United States)

2010-07-01

... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Transportation provided by public... BASIS OF DISABILITY BY PUBLIC ACCOMMODATIONS AND IN COMMERCIAL FACILITIES Specific Requirements § 36.310 Transportation provided by public accommodations. (a) General. (1) A public accommodation that provides...

[Monochromatic aberration in accommodation. Dynamic wavefront analysis].

Science.gov (United States)

Fritzsch, M; Dawczynski, J; Jurkutat, S; Vollandt, R; Strobel, J

2011-06-01

Monochromatic aberrations may influence the visual acuity of the eye. They are not stable and can be affected by different factors. The subject of the following paper is the dynamic investigation of the changes in wavefront aberration with accommodation. Dynamic measurement of higher and lower order aberrations was performed with a WASCA Wavefront Analyzer (Carl-Zeiss-Meditec) and a specially constructed target device for aligning objects in far and near distances on 25 subjects aged from 15 to 27 years old. Wavefront aberrations showed some significant changes in accommodation. In addition to the characteristic sphere reaction accompanying miosis and changes in horizontal prism (Z(1) (1)) in the sense of a convergence movement of the eyeball also occurred. Furthermore defocus rose (Z(2) (0)) and astigmatism (Z(2) (-2)) changed. In higher-order aberrations a decrease in coma-like Zernike polynomials (Z(3) (-1), Z(3) (1)) was found. The most obvious change appeared in spherical aberration (Z(4) (0)) which increased and changed from positive to negative. In addition the secondary astigmatism (Z(4) (-2)) and quadrafoil (Z(4) (4)) rise also increased. The total root mean square (RMS), as well as the higher-order aberrations (RMS-HO) significantly increased in accommodation which is associated with a theoretical reduction of visual acuity. An analysis of the influence of pupil size on aberrations showed significant increases in defocus, spherical aberration, quadrafoil, RMS and RMS HO by increasing pupil diameter. By accommodation-associated miosis, the growing aberrations are partially compensated by focusing on near objects. Temporal analysis of the accommodation process with dynamic wavefront analysis revealed significant delays in pupil response and changing of prism in relation to the sphere reaction. In accommodation to near objects a discrete time ahead of third order aberrations in relation to the sphere response was found. Using dynamic wavefront measurement

First Passage Time Intervals of Gaussian Processes

Science.gov (United States)

Perez, Hector; Kawabata, Tsutomu; Mimaki, Tadashi

1987-08-01

The first passage time problem of a stationary Guassian process is theretically and experimentally studied. Renewal functions are derived for a time-dependent boundary and numerically calculated for a Gaussian process having a seventh-order Butterworth spectrum. The results show a multipeak property not only for the constant boundary but also for a linearly increasing boundary. The first passage time distribution densities were experimentally determined for a constant boundary. The renewal functions were shown to be a fairly good approximation to the distribution density over a limited range.

Computer-animated model of accommodation and presbyopia.

Science.gov (United States)

Goldberg, Daniel B

2015-02-01

To understand, demonstrate, and further research the mechanisms of accommodation and presbyopia. Private practice, Little Silver, New Jersey, USA. Experimental study. The CAMA 2.0 computer-animated model of accommodation and presbyopia was produced in collaboration with an experienced medical animator using Autodesk Maya animation software and Adobe After Effects. The computer-animated model demonstrates the configuration and synchronous movements of all accommodative elements. A new classification of the zonular apparatus based on structure and function is proposed. There are 3 divisions of zonular fibers; that is, anterior, crossing, and posterior. The crossing zonular fibers form a scaffolding to support the lens; the anterior and posterior zonular fibers work reciprocally to achieve focused vision. The model demonstrates the important support function of Weiger ligament. Dynamic movement of the ora serrata demonstrates that the forces of ciliary muscle contraction store energy for disaccommodation in the elastic choroid. The flow of aqueous and vitreous provides strong evidence for our understanding of the hydrodynamic interactions during the accommodative cycle. The interaction may result from the elastic stretch in the choroid transmitted to the vitreous rather than from vitreous pressue. The model supports the concept that presbyopia results from loss of elasticity and increasing ocular rigidity in both the lenticular and extralenticular structures. The computer-animated model demonstrates the structures of accommodation moving in synchrony and might enhance understanding of the mechanisms of accommodation and presbyopia. Dr. Goldberg is a consultant to Acevision, Inc., and Bausch & Lomb. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Symptomatic accommodative disorders and asthenopia: Prevalence and association in Ghanaian children

Directory of Open Access Journals (Sweden)

Charles Darko-Takyi

2016-11-01

Full Text Available Background: There is a scarcity of data on asthenopia and accommodative disorders in children in Ghana as optometrists sometimes fail to carry out comprehensive assessments because of the lack of appropriate instruments. Aim: To establish the prevalence of asthenopic symptoms and symptomatic accommodative disorders among Junior High School children in Cape Coast metropolis (in their habitual vision state and to investigate if there are any associations between asthenopic symptoms and the disorders. Method: A prospective cross-sectional school-based study using a multistage sample of 627 participants aged 12–17 years from Junior High Schools in Cape Coast metropolis, Ghana, was conducted. Participants completed a reliable asthenopic symptoms questionnaire (Cronbach’s α = 0.866, and 220 participants who expressed two or more severe or very severe symptoms were selected for comprehensive accommodative system assessment over their habitual vision state. Results: The prevalence of symptoms of asthenopia (two or more severe or very severe and symptomatic accommodative disorders were 35.1% and 17.4% respectively. For specific symptomatic accommodative disorders, the prevalence was as follows: 7.7% accommodative insufficiency, 4.5% accommodative infacility, 1.4% accommodative excess and 3.8% accommodative fatigue. There were significant associations between some specific accommodative disorders and some specific asthenopic symptoms even though these asthenopic symptoms overlapped in other accommodative disorders. Conclusion: Specific asthenopic symptoms do not discriminate between the presences of specific types of accommodative disorders. A comprehensive accommodative system assessment with appropriate instruments is relevant to the diagnosis and management of accommodative disorders to relieve asthenopic symptoms.

Corneal changes with accommodation using dual Scheimpflug photography.

Science.gov (United States)

Sisó-Fuertes, Irene; Domínguez-Vicent, Alberto; del Águila-Carrasco, Antonio; Ferrer-Blasco, Teresa; Montés-Micó, Robert

2015-05-01

To assess whether corneal parameters and aberrations are affected by accommodation. Optics Department, University of Valencia, Valencia, Spain. Prospective cross-sectional study. The Galilei G4 dual Scheimpflug device was used to obtain data on the anterior and posterior axial curvatures, total corneal power (TCP), and corneal pachymetry from 3 corneal zones (central: 0.0 up to 4.0 mm; paracentral or mid: 4.0 up to 7.0 mm; peripheral: 7.0 up to 10.0 mm) in young emmetropic eyes in the unaccommodated and 4 accommodated states (from -1.0 to -4.0 diopters [D] in 1.0 D steps). The 2nd-, 3rd-, and 4th-order aberrations as well as the root mean square (RMS) were also determined for the entire cornea at the same accommodative demands. The study evaluated 7 subjects (12 eyes). No significant changes in any measured parameter were found during accommodation for any corneal zone (P > .05). Statistically significant differences were found in the various corneal zones when it was assumed they were constant with accommodation (P the high standard deviation values. Different parameters in various zones of the cornea as well as corneal aberrations were stable during accommodation. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Shape design of internal cooling passages within a turbine blade

Science.gov (United States)

Nowak, Grzegorz; Nowak, Iwona

2012-04-01

The article concerns the optimization of the shape and location of non-circular passages cooling the blade of a gas turbine. To model the shape, four Bezier curves which form a closed profile of the passage were used. In order to match the shape of the passage to the blade profile, a technique was put forward to copy and scale the profile fragments into the component, and build the outline of the passage on the basis of them. For so-defined cooling passages, optimization calculations were carried out with a view to finding their optimal shape and location in terms of the assumed objectives. The task was solved as a multi-objective problem with the use of the Pareto method, for a cooling system composed of four and five passages. The tool employed for the optimization was the evolutionary algorithm. The article presents the impact of the population on the task convergence, and discusses the impact of different optimization objectives on the Pareto optimal solutions obtained. Due to the problem of different impacts of individual objectives on the position of the solution front which was noticed during the calculations, a two-step optimization procedure was introduced. Also, comparative optimization calculations for the scalar objective function were carried out and set up against the non-dominated solutions obtained in the Pareto approach. The optimization process resulted in a configuration of the cooling system that allows a significant reduction in the temperature of the blade and its thermal stress.

Marketing of Accommodation services : Case-Hotel Azam Cameroon

OpenAIRE

Youkam, Germaine

2012-01-01

Cameroon is Africa in miniature with a lot of tourist attractions owing to its geological and cultural diversity. Natural features include beaches, deserts, mountains, rainforests, and savannas. Accommodation services have been a grand phenomenon within the tourism industry in Cameroon. The accommodation sector has developed tremendously within the past decades. The objective of this research work was to find about out the marketing of accommodation services in Cameroon with Hotel Azam as...

Workplace accommodations for people with mental illness: a scoping review.

Science.gov (United States)

McDowell, Caitlin; Fossey, Ellie

2015-03-01

Disability discrimination legislation means that employees with a disability or mental illness are legally entitled to reasonable workplace accommodations that enable them to work effectively and safely. This scoping review aims to investigate the types of workplace accommodations provided for people with mental illness, and their costs and benefits. A literature search was conducted using five electronic databases. Peer reviewed research articles published between 1993 and June 2013 were included in this scoping review and their quality was assessed. Opinion papers, reports, and case descriptions were excluded. Nine studies explored workplace accommodations for people with mental illness. The most commonly reported work-related accommodations were flexible scheduling/reduced hours, modified training and supervision, and modified job duties/descriptions. The least common type of accommodation was physical modification to the workplace. For employees with persistent mental illness who were accessing a supported employment agency, the majority of accommodations related to support from the job coach or employment specialist, such as facilitating communication with the employer during hiring or on the job. The quality of the studies varied considerably and the benefits of the accommodations are not yet well documented. There is limited evidence that a larger number of workplace accommodations are associated with longer job tenure. Workplace accommodations appear to be important to support employees with mental illness, but more accessible information about how disability discrimination legislation applies to this population is needed. Future research should address the implementation and effectiveness of mental health-related workplace accommodations.

Spark PRM: Using RRTs within PRMs to efficiently explore narrow passages

KAUST Repository

Shi, Kensen; Denny, Jory; Amato, Nancy M.

2014-01-01

© 2014 IEEE. Probabilistic RoadMaps (PRMs) have been successful for many high-dimensional motion planning problems. However, they encounter difficulties when mapping narrow passages. While many PRM sampling methods have been proposed to increase the proportion of samples within narrow passages, such difficult planning areas still pose many challenges. We introduce a novel algorithm, Spark PRM, that sparks the growth of Rapidly-expanding Random Trees (RRTs) from narrow passage samples generated by a PRM. The RRT rapidly generates further narrow passage samples, ideally until the passage is fully mapped. After reaching a terminating condition, the tree stops growing and is added to the roadmap. Spark PRM is a general method that can be applied to all PRM variants. We study the benefits of Spark PRM with a variety of sampling strategies in a wide array of environments. We show significant speedups in computation time over RRT, Sampling-based Roadmap of Trees (SRT), and various PRM variants.

Spark PRM: Using RRTs within PRMs to efficiently explore narrow passages

KAUST Repository

Shi, Kensen

2014-05-01

© 2014 IEEE. Probabilistic RoadMaps (PRMs) have been successful for many high-dimensional motion planning problems. However, they encounter difficulties when mapping narrow passages. While many PRM sampling methods have been proposed to increase the proportion of samples within narrow passages, such difficult planning areas still pose many challenges. We introduce a novel algorithm, Spark PRM, that sparks the growth of Rapidly-expanding Random Trees (RRTs) from narrow passage samples generated by a PRM. The RRT rapidly generates further narrow passage samples, ideally until the passage is fully mapped. After reaching a terminating condition, the tree stops growing and is added to the roadmap. Spark PRM is a general method that can be applied to all PRM variants. We study the benefits of Spark PRM with a variety of sampling strategies in a wide array of environments. We show significant speedups in computation time over RRT, Sampling-based Roadmap of Trees (SRT), and various PRM variants.

Vergence driven accommodation with simulated disparity in myopia and emmetropia.

Science.gov (United States)

Maiello, Guido; Kerber, Kristen L; Thorn, Frank; Bex, Peter J; Vera-Diaz, Fuensanta A

2018-01-01

The formation of focused and corresponding foveal images requires a close synergy between the accommodation and vergence systems. This linkage is usually decoupled in virtual reality systems and may be dysfunctional in people who are at risk of developing myopia. We study how refractive error affects vergence-accommodation interactions in stereoscopic displays. Vergence and accommodative responses were measured in 21 young healthy adults (n=9 myopes, 22-31 years) while subjects viewed naturalistic stimuli on a 3D display. In Step 1, vergence was driven behind the monitor using a blurred, non-accommodative, uncrossed disparity target. In Step 2, vergence and accommodation were driven back to the monitor plane using naturalistic images that contained structured depth and focus information from size, blur and/or disparity. In Step 1, both refractive groups converged towards the stereoscopic target depth plane, but the vergence-driven accommodative change was smaller in emmetropes than in myopes (F 1,19 =5.13, p=0.036). In Step 2, there was little effect of peripheral depth cues on accommodation or vergence in either refractive group. However, vergence responses were significantly slower (F 1,19 =4.55, p=0.046) and accommodation variability was higher (F 1,19 =12.9, p=0.0019) in myopes. Vergence and accommodation responses are disrupted in virtual reality displays in both refractive groups. Accommodation responses are less stable in myopes, perhaps due to a lower sensitivity to dioptric blur. Such inaccuracies of accommodation may cause long-term blur on the retina, which has been associated with a failure of emmetropization. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of Vision Therapy on Accommodation in Myopic Chinese Children

Directory of Open Access Journals (Sweden)

Martin Ming-Leung Ma

2016-01-01

Full Text Available Introduction. We evaluated the effectiveness of office-based accommodative/vergence therapy (OBAVT with home reinforcement to improve accommodative function in myopic children with poor accommodative response. Methods. This was a prospective unmasked pilot study. 14 Chinese myopic children aged 8 to 12 years with at least 1 D of lag of accommodation were enrolled. All subjects received 12 weeks of 60-minute office-based accommodative/vergence therapy (OBAVT with home reinforcement. Primary outcome measure was the change in monocular lag of accommodation from baseline visit to 12-week visit measured by Shinnipon open-field autorefractor. Secondary outcome measures were the changes in accommodative amplitude and monocular accommodative facility. Results. All participants completed the study. The lag of accommodation at baseline visit was 1.29 ± 0.21 D and it was reduced to 0.84 ± 0.19 D at 12-week visit. This difference (−0.46 ± 0.22 D; 95% confidence interval: −0.33 to −0.58 D is statistically significant (p<0.0001. OBAVT also increased the amplitude and facility by 3.66 ± 3.36 D (p=0.0013; 95% confidence interval: 1.72 to 5.60 D and 10.9 ± 4.8 cpm (p<0.0001; 95% confidence interval: 8.1 to 13.6 cpm, respectively. Conclusion. Standardized 12 weeks of OBAVT with home reinforcement is able to significantly reduce monocular lag of accommodation and increase monocular accommodative amplitude and facility. A randomized clinical trial designed to investigate the effect of vision therapy on myopia progression is warranted.

New Compact Accommodometer to Measure Accommodation Amplitude as a Biomarker.

Science.gov (United States)

Ide, Takeshi; Negishi, Kazuno; Yamaguchi, Takefumi; Hara, Shuya; Toda, Ikuko; Tsubota, Kazuo

2012-01-01

This study aimed to evaluate a newly designed compact accommodometer (CA) and compare this with a conventional accommodometer for measuring accommodation as a biomarker for aging and lifestyle. This is an observational case series. Accommodative amplitude was measured using 2 different accommodometers in 114 patients. We obtained the data of the near-point accommodation amplitude. Subsequently, we used smoking habit as an example of lifestyle-related factor to evaluate its effect on the accommodative power. The first part of the study included 60 eyes of 60 men and 54 eyes of 54 women, with a mean (SD) age of 43.8 (12.9) years (range, 18-58 years). There was a consistency within each measuring method despite a significant difference between the 2 devices (P the second part of the study, we found a significant correlation between age and accommodative amplitude both in smokers and in nonsmokers. The accommodative amplitude of the smoker group was significantly lower than that of the nonsmoker group (P the conventional accommodometer for measuring accommodative amplitude as an aging biomarker. Lifestyle factors can affect the magnitude of accommodation, which can be measured by this newly developed CA.

The provision of workplace accommodations following cancer: survivor, provider, and employer perspectives.

Science.gov (United States)

Stergiou-Kita, Mary; Pritlove, Cheryl; van Eerd, Dwayne; Holness, Linn D; Kirsh, Bonnie; Duncan, Andrea; Jones, Jennifer

2016-06-01

With improvements in screening, diagnosis, and treatment, the number of persons surviving cancer and staying at or returning to work is increasing. While workplace accommodations optimize workers' abilities to participate in the workforce, there has been little in-depth investigation of the types of accommodations reported to have been provided to cancer survivors and the processes relevant to ensuring their successful implementation. We employed an exploratory qualitative method and conducted 40 semi-structured interviews with three groups: (i) cancers survivors (n = 16), (ii) health/vocational service providers (n = 16), and (iii) employer representatives (n = 8) to explore return to work and accommodation processes, successes, and challenges. An inductive thematic analysis approach was used to analyze the data. Four types of accommodations were recommended: (1) graduated return to work plans and flexible scheduling, (2) modification of work duties and performance expectations, (3) retraining and supports at the workplace, and (4) modification of the physical work environment and/or the provision of adaptive aids/technologies. Processes relevant to ensuring effective accommodations included: (1) developing knowledge about accommodations, (2) employer's ability to accommodate, (3) negotiating reasonable accommodations, (4) customizing accommodations, and (5) implementing and monitoring accommodation plans. Accommodation challenges included: (1) survivors' fears requesting accommodations, (2) developing clear and specific accommodations, (3) difficult to accommodate jobs, and (4) workplace challenges, including strained pre-cancer workplace relationships, insufficient/inflexible workplace policies, employer concerns regarding productivity and precedent setting, and limited modified duties. Accommodations need to be customized and clearly linked to survivors' specific job demands, work context, and available workplace supports. Survivors need to feel

Cannibalism and predation as paths for horizontal passage of Wolbachia between terrestrial isopods.

Directory of Open Access Journals (Sweden)

Winka Le Clec'h

Full Text Available The alpha-proteobacteria Wolbachia are the most widespread endosymbionts in arthropods and nematodes. Mainly maternally inherited, these so-called sex parasites have selected several strategies that increase their vertical dispersion in host populations. However, the lack of congruence between the Wolbachia and their host phylogenies suggests frequent horizontal transfers. One way that could be used for horizontal Wolbachia transfers between individuals is predation. The aim of this study was to test whether horizontal passage of Wolbachia is possible when an uninfected terrestrial isopod eats an infected one. After having eaten Armadillidium vulgare harbouring Wolbachia, the predator-recipients (the two woodlice A. vulgare and Porcellio dilatatus dilatatus that were initially Wolbachia-free were tested positive for the presence of Wolbachia both by quantitative PCR and Fluorescence in situ Hybridization (FISH. Even if the titers were low compared to vertically infected individuals, this constitutes the first demonstration of Wolbachia occurrence in various organs of an initially uninfected host after eating an infected one.

Accommodating Different Learning Styles

DEFF Research Database (Denmark)

Ovesen, Nis

2014-01-01

Design engineering educations often struggle to accommodate a highly diverse group of students as it combines an equally diverse range of topics in one education. This paper investigates how a specific course, Mathematics and Form, integrates two distinct areas into one course with the aim of fac...... shapes and form, whereas other types of students do not. The results thereby underpin that learning is typically based on individual preferences and that cross-disciplinary educational programmes have to accommodate this....... of facilitating learning across this diverse group of students. The paper is based on a survey with 99 former participants of the course as respondents. The results of the survey imply that certain types of students benefit from the combination of mathematical theory and practical exercises related to basic...

Accommodating Picky Palates

Science.gov (United States)

Lum, Lydia

2007-01-01

Healthy gourmet offerings are fast becoming the norm at college dining halls around the country. At a time when the children of Baby Boomers are hitting higher education in record numbers, college officials have scrambled to accommodate their picky palates and their insistence for healthier meals than were served to past generations. At the same…

Aquatic organism passage at road-stream crossings—synthesis and guidelines for effectiveness monitoring

Science.gov (United States)

Hoffman, Robert L.; Dunham, Jason B.; Hansen, Bruce P.

2012-01-01

Restoration and maintenance of passage for aquatic organisms at road-stream crossings represents a major management priority, involving an investment of hundreds of millions of dollars (for example, U.S. Government Accounting Office, 2001). In recent years, passage at hundreds of crossings has been restored, primarily by replacing barrier road culverts with bridges or stream simulation culverts designed to pass all species and all life stages of aquatic life and simulate natural hydro-geomorphic processes (U.S. Forest Service, 2008). The current situation has motivated two general questions: 1. Are current design standards for stream simulation culverts adequately re-establishing passage for aquatic biota? and 2. How do we monitor and evaluate effectiveness of passage restoration? To address the latter question, a national workshop was held in March 2010, in Portland, Oregon. The workshop included experts on aquatic organism passage from across the nation (see table of participants, APPENDIX) who addressed four classes of methods for monitoring effectiveness of aquatic organism passage—individual movement, occupancy, demography, and genetics. This report has been written, in part, for field biologists who will be undertaking and evaluating the effectiveness of aquatic organism passage restoration projects at road-stream crossings. The report outlines basic methods for evaluating road-stream crossing passage impairment and restoration and discusses under what circumstances and conditions each method will be useful; what questions each method can potentially answer; how to design and implement an evaluation study; and points out the fundamental reality that most evaluation projects will require special funding and partnerships among researchers and resource managers. The report is organized into the following sections, which can be read independently: 1. Historical context: In this section, we provide a brief history of events leading up to the present situation

Vascular smooth muscle cells exhibit a progressive loss of rigidity with serial culture passaging.

Science.gov (United States)

Dinardo, Carla Luana; Venturini, Gabriela; Omae, Samantha Vieira; Zhou, Enhua H; da Motta-Leal-Filho, Joaquim Maurício; Dariolli, Rafael; Krieger, José Eduardo; Alencar, Adriano Mesquita; Costa Pereira, Alexandre

2012-01-01

One drawback of in vitro cell culturing is the dedifferentiation process that cells experience. Smooth muscle cells (SMC) also change molecularly and morphologically with long term culture. The main objective of this study was to evaluate if culture passages interfere in vascular SMC mechanical behavior. SMC were obtained from five different porcine arterial beds. Optical magnetic twisting cytometry (OMTC) was used to characterize mechanically vascular SMC from different cultures in distinct passages and confocal microscopy/western blotting, to evaluate cytoskeleton and extracellular matrix proteins. We found that vascular SMC rigidity or viscoelastic complex modulus (G) decreases with progression of passages. A statistically significant negative correlation between G and passage was found in four of our five cultures studied. Phalloidin-stained SMC from higher passages exhibited lower mean signal intensity per cell (confocal microscopy) and quantitative western blotting analysis showed a decrease in collagen I content throughout passages. We concluded that vascular SMC progressively lose their stiffness with serial culture passaging. Thus, limiting the number of passages is essential for any experiment measuring viscoelastic properties of SMC in culture.

Quality of Vision in Eyes With Epiphora Undergoing Lacrimal Passage Intubation.

Science.gov (United States)

Koh, Shizuka; Inoue, Yasushi; Ochi, Shintaro; Takai, Yoshihiro; Maeda, Naoyuki; Nishida, Kohji

2017-09-01

To investigate visual function and optical quality in eyes with epiphora undergoing lacrimal passage intubation. Prospective case series. Thirty-four eyes of 30 patients with lacrimal passage obstruction were enrolled. Before and 1 month after lacrimal passage intubation, functional visual acuity (FVA), higher-order aberrations (HOAs), lower tear meniscus, and tear clearance were assessed. An FVA measurement system was used to examine changes in continuous visual acuity (VA) over time, and visual function parameters such as FVA, visual maintenance ratio, and blink frequency were obtained. Sequential ocular HOAs were measured for 10 seconds after the blink using a wavefront sensor. Aberration data were analyzed in the central 4 mm for coma-like, spherical-like, and total HOAs. Fluctuation and stability indices of the total HOAs over time were calculated. Lower tear meniscus was assessed by anterior segment optical coherence tomography. After lacrimal passage intubation, visual function significantly improved, as indicated by improved FVA (P = .003) and visual maintenance ratio (P function and optical quality via patency of the lacrimal passage. Copyright © 2017 Elsevier Inc. All rights reserved.

Fire passage on geomorphic fractures in Cerrado: effect on vegetation

Directory of Open Access Journals (Sweden)

Otacílio Antunes Santana

2017-01-01

Full Text Available Geomorphic fracture is a natural geologic formation that sometimes forms a deep fissure in the rock with the establishment of soil and vegetation. The objective of this work was to analyze vegetation within geomorphic fractures under the effect of wildfire passage. The biometric variables evaluated before and after fire passage were: diameter, height, leaf area index, timber volume, grass biomass, number of trees and shrubs and of species. Results (in fractures were compared to adjacent areas (control. The effect of wildfire passage on vegetation within geomorphic fractures was not significant because fire followed plant biomass bed and when it met the fracture (wetter, it changed from soil surface to canopy surface (jump fire effect, affecting without significance the number of plants or species; so, fracture could be plants refuge against fire passage. We could infer in our experimental model that quality of plant biomass bed could be more significant than quantity, and microclimate variability recruits plants to the refuge (geomorphic fracture.

Knotting probabilities after a local strand passage in unknotted self-avoiding polygons

International Nuclear Information System (INIS)

Szafron, M L; Soteros, C E

2011-01-01

We investigate, both theoretically and numerically, the knotting probabilities after a local strand passage is performed in an unknotted self-avoiding polygon (SAP) on the simple cubic lattice. In the polygons studied, it is assumed that two polygon segments have already been brought close together for the purpose of performing a strand passage. This restricts the polygons considered to those that contain a specific pattern called Θ at a fixed location; an unknotted polygon containing Θ is called a Θ-SAP. It is proved that the number of n-edge Θ-SAPs grows exponentially (with n) at the same rate as the total number of n-edge unknotted SAPs (those with no prespecified strand passage structure). Furthermore, it is proved that the same holds for subsets of n-edge Θ-SAPs that yield a specific after-strand-passage knot-type. Thus, the probability of a given after-strand-passage knot-type does not grow (or decay) exponentially with n. Instead, it is conjectured that these after-strand-passage knot probabilities approach, as n goes to infinity, knot-type dependent amplitude ratios lying strictly between 0 and 1. This conjecture is supported by numerical evidence from Monte Carlo data generated using a composite (aka multiple) Markov chain Monte Carlo BFACF algorithm developed to study Θ-SAPs. A new maximum likelihood method is used to estimate the critical exponents relevant to this conjecture. We also obtain strong numerical evidence that the after-strand-passage knotting probability depends on the local structure around the strand-passage site. If the local structure and the crossing sign at the strand-passage site are considered, then we observe that the more 'compact' the local structure, the less likely the after-strand-passage polygon is to be knotted. This trend for compactness versus knotting probability is consistent with results obtained for other strand-passage models; however, we are the first to note the influence of the crossing-sign information. We

First-passage exponents of multiple random walks

International Nuclear Information System (INIS)

Ben-Naim, E; Krapivsky, P L

2010-01-01

We investigate first-passage statistics of an ensemble of N noninteracting random walks on a line. Starting from a configuration in which all particles are located in the positive half-line, we study S n (t), the probability that the nth rightmost particle remains in the positive half-line up to time t. This quantity decays algebraically, S n (t)∼t -β n , in the long-time limit. Interestingly, there is a family of nontrivial first-passage exponents, β 1 2 N-1 ; the only exception is the two-particle case where β 1 = 1/3. In the N → ∞ limit, however, the exponents attain a scaling form, β n (N) → β(z) with z=(n-N/2)/√N. We also demonstrate that the smallest exponent decays exponentially with N. We deduce these results from first-passage kinetics of a random walk in an N-dimensional cone and confirm them using numerical simulations. Additionally, we investigate the family of exponents that characterizes leadership statistics of multiple random walks and find that in this case, the cone provides an excellent approximation.

Data Overview for Sensor Fish Samples Acquired at Ice Harbor, John Day, and Bonneville II Dams in 2005, 2006, and 2007

Energy Technology Data Exchange (ETDEWEB)

Carlson, Thomas J.; Duncan, Joanne P.; Deng, Zhiqun

2008-03-12

The purpose of this work was to acquire Sensor Fish data on turbine passage at Bonneville II, John Day, and Ice Harbor dams for later analysis and use. The original data sets have been entered into a database and are being maintained by Pacific Northwest National Laboratory pending delivery to the U.S. Army Corps of Engineers when requested. This report provides documentation for the data sets acquired and details about the operations of the Sensor Fish and interpretation of Sensor Fish data that will be necessary for later use of the acquired data. A limited review of the acquired data was conducted to assess its quality and to extract information that might prove useful to its later use.

Flow characteristics in nuclear steam turbine blade passage

International Nuclear Information System (INIS)

Ahn, H.J.; Yoon, W.H.; Kwon, S.B.

1995-01-01

The rapid expansion of condensable gas such as moist air or steam gives rise to nonequilibrium condensation. As a result of irreversibility of condensation process in the nuclear steam turbine blade passage, the entropy of the flow increases, and the efficiency of the turbine decreases. In the present study, in order to investigate the flow characteristics of moist air in two-dimensional turbine blade passage which is made from the configuration of the last stage tip section of the actual nuclear steam turbine moving blade, the static pressures along both pressure and suction sides of blade are measured by static pressure taps and the distribution of Mach number on both sides of the blade are obtained by using the measured static pressure. Also, the flow field is visualized by a Schlieren system. From the experimental results, the effects of the stagnation temperature and specific humidity on the flow properties in the two dimensional steam turbine blade passage are clearly identified

Impact of water-accommodated fractions of crude oil on Atlantic cod, Gadus morhua following chronic exposure

International Nuclear Information System (INIS)

Khan, R.

2010-01-01

This study examined the long-term effects of hydrocarbon exposure on the gonadal development of fish. Mature Atlantic cod (Gadus morhua) were exposed to low concentrations of water accommodated fractions (WAFs) of polycyclic aromatic hydrocarbons (PAHs) in an ambient flowthrough seawater system. Some PAH-exposed cod groups were depurated afterwards for 38 to 287 days. Mortality was rare, and external lesions occurred only in the PAH-exposed groups. The gonado-somatic index revealed that gonadal development was disrupted in both sexes and spawning and spermiation was delayed in the 33 depurated PAH-groups. The findings indicate that chronic exposure to WAFs in the water column may have an adverse effect on reproduction in Atlantic cod.

Occlusal accommodation and mouthguards for prevention of orofacial trauma.

Science.gov (United States)

Geary, Julian Lindsay; Clifford, Thomas Joseph; Kinirons, Martin James

2009-01-01

The aim of this study was to investigate the effect of two types of occlusal accommodation on the arch separation in centric and eccentric arch positions and to assess the opposing tooth contacts in professionally made, thermoformed sports mouthguards. Maxillary and mandibular alginate impressions, a wax interocclusal record of centric occlusion together with maxillary/condylar face-bow registrations, were recorded clinically for 10 undergraduate dental students who are sports activist volunteers of the School of Medicine and Dentistry, Queen's University Belfast. Two ethylene vinyl acetate thermoformed maxillary mouthguards were made for each player (N = 20) using a standardised procedure. Ten mouthguards served both as the control (i.e. the non-accommodated) group and also the accommodated, occlusally 'imprinted' group. The other 10 mouthguards served as the accommodated, occlusally 'ground' group. Casts were articulated, each non-accommodated and accommodated mouthguard was seated and the extent of the interocclusal opening was recorded in all three arch relationships. The number of mouthguard and mandibular tooth contacts were also recorded in each position. The increased vertical occlusal dimension that was found in the presence of non-accommodated mouthguards equated to the full-sheet thickness of the material that was used to form the mouthguards. Only mouthguards accommodated by grinding retained high levels of occlusal contact in all arch relationships that were tested. Within the limitations of this study, the modification of the occlusal surface made by flat grinding reduced the arch separation in eccentric movements and increased the opposing tooth contacts in custom-made mouthguards. This may contribute to increased comfort, compliance and the protective effect of these appliances thus resulting in a reduction of injuries to the teeth, arches and soft tissues.

Comparison of tests of accommodation for computer users.

Science.gov (United States)

Kolker, David; Hutchinson, Robert; Nilsen, Erik

2002-04-01

With the increased use of computers in the workplace and at home, optometrists are finding more patients presenting with symptoms of Computer Vision Syndrome. Among these symptomatic individuals, research supports that accommodative disorders are the most common vision finding. A prepresbyopic group (N= 30) and a presbyopic group (N = 30) were selected from a private practice. Assignment to a group was determined by age, accommodative amplitude, and near visual acuity with their distance prescription. Each subject was given a thorough vision and ocular health examination, then administered several nearpoint tests of accommodation at a computer working distance. All the tests produced similar results in the presbyopic group. For the prepresbyopic group, the tests yielded very different results. To effectively treat symptomatic VDT users, optometrists must assess the accommodative system along with the binocular and refractive status. For presbyopic patients, all nearpoint tests studied will yield virtually the same result. However, the method of testing accommodation, as well as the test stimulus presented, will yield significantly different responses for prepresbyopic patients. Previous research indicates that a majority of patients prefer the higher plus prescription yielded by the Gaussian image test.

Phase I Water Rental Pilot Project : Snake River Resident Fish and Wildlife Resources and Management Recommendations.

Energy Technology Data Exchange (ETDEWEB)

Riggin, Stacey H.; Hansen, H. Jerome

1992-10-01

The Idaho Water Rental Pilot Project was implemented as a part of the Non-Treaty Storage Fish and Wildlife Agreement (NTSA) between Bonneville Power Administration and the Columbia Basin Fish and Wildlife Authority. The goal of the project is to improve juvenile and adult salmon and steelhead passage in the lower Snake River with the use of rented water for flow augmentation. The primary purpose of this project is to summarize existing resource information and provide recommendations to protect or enhance resident fish and wildlife resources in Idaho with actions achieving flow augmentation for anadromous fish. Potential impacts of an annual flow augmentation program on Idaho reservoirs and streams are modeled. Potential sources of water for flow augmentation and operational or institutional constraints to the use of that water are identified. This report does not advocate flow augmentation as the preferred long-term recovery action for salmon. The state of Idaho strongly believes that annual drawdown of the four lower Snake reservoirs is critical to the long-term enhancement and recovery of salmon (Andrus 1990). Existing water level management includes balancing the needs of hydropower production, irrigated agriculture, municipalities and industries with fish, wildlife and recreation. Reservoir minimum pool maintenance, water quality and instream flows are issues of public concern that will be directly affected by the timing and quantity of water rental releases for salmon flow augmentation, The potential of renting water from Idaho rental pools for salmon flow augmentation is complicated by institutional impediments, competition from other water users, and dry year shortages. Water rental will contribute to a reduction in carryover storage in a series of dry years when salmon flow augmentation is most critical. Such a reduction in carryover can have negative impacts on reservoir fisheries by eliminating shoreline spawning beds, reducing available fish habitat

First Passage Moments of Finite-State Semi-Markov Processes

Energy Technology Data Exchange (ETDEWEB)

Warr, Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cordeiro, James [Air Force Research Lab. (AFRL), Wright-Patterson AFB, OH (United States)

2014-03-31

In this paper, we discuss the computation of first-passage moments of a regular time-homogeneous semi-Markov process (SMP) with a finite state space to certain of its states that possess the property of universal accessibility (UA). A UA state is one which is accessible from any other state of the SMP, but which may or may not connect back to one or more other states. An important characteristic of UA is that it is the state-level version of the oft-invoked process-level property of irreducibility. We adapt existing results for irreducible SMPs to the derivation of an analytical matrix expression for the first passage moments to a single UA state of the SMP. In addition, consistent point estimators for these first passage moments, together with relevant R code, are provided.

The Assessment of Accommodation and Convergence System in the Bank Employees

Directory of Open Access Journals (Sweden)

Monireh Mahjoob

2013-02-01

Full Text Available Background: Regarding the high outbreak rate of the eye disorders and problems particularly accommodation disorders and convergence insufficiency in computer users, the study tries to determine the convergence, accommodation system, condition, fusion reserves and vision dimension in bank employees (who work with computers and the control group (who are not computer users and then to compare the mentioned parameters in the two groups. Materials and Methods: In this cross-sectional and observational study a total of 44 bank employees and 44 people as the control group members were selected randomly. Initially, refractive problems were reformed, and then accommodation, convergence and vision dimension evaluative tests were conducted. The test included measuring the near point of convergence, jump convergence, phoria, accommodation range (one eye, both eyes, ease of accommodation (one eye, both eyes, positive and negative related accommodation, near fusion versions and TNO.Results: Our results showed that there was a not significant difference among the near point of convergence, jump convergence, near phoria, accommodation range (one eye and both eyes, ease of accommodation (one eye, both eyes, positive and negative related accommodation in bank employees and control group.Conclusion: Regarding the studies, the outbreak rate of accommodation and convergence disorders is higher in bank employees than the control group which would be due to over working with computer within a fixed interval.

Evidence that convergence rather than accommodation controls intermittent distance exotropia.

Science.gov (United States)

Horwood, Anna M; Riddell, Patricia M

2012-03-01

This study considered whether vergence drives accommodation or accommodation drives vergence during the control of distance exotropia for near fixation. High accommodative convergence to accommodation (AC/A) ratios are often used to explain this control, but the role of convergence to drive accommodation (the CA/C relationship) is rarely considered. Atypical CA/C characteristics could equally, or better, explain common clinical findings. Nineteen distance exotropes, aged 4-11 years, were compared while controlling their deviation with 27 non-exotropic controls aged 5-9 years. Simultaneous vergence and accommodation responses were measured to a range of targets incorporating different combinations of blur, disparity and looming cues at four fixation distances between 2 m and 33 cm. Stimulus and response AC/A and CA/C ratios were calculated. Accommodation responses for near targets (p = 0.017) and response gains (p = 0.026) were greater in the exotropes than in the controls. Despite higher clinical stimulus AC/A ratios, the distance exotropes showed lower laboratory response AC/A ratios (p = 0.02), but significantly higher CA/C ratios (p = 0.02). All the exotropes, whether the angle changed most with lenses ('controlled by accommodation') or on occlusion ('controlled by fusion'), used binocular disparity not blur as their main cue to target distance. Increased vergence demand to control intermittent distance exotropia for near also drives significantly more accommodation. Minus lens therapy is more likely to act by correcting overaccommodation driven by controlling convergence, rather than by inducing blur-driven vergence. The use of convergence as a major drive to accommodation explains many clinical characteristics of distance exotropia, including apparently high near stimulus AC/A ratios. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

On correlations between certain random variables associated with first passage Brownian motion

International Nuclear Information System (INIS)

Kearney, Michael J; Pye, Andrew J; Martin, Richard J

2014-01-01

We analyse how the area swept out by a Brownian motion up to its first passage time correlates with the first passage time itself, obtaining several exact results in the process. Additionally, we analyse the relationship between the time average of a Brownian motion during a first passage and the maximum value attained. The results, which find various applications, are in excellent agreement with simulations. (paper)

Location as a determinant of accommodation prices: managerial approach

OpenAIRE

Napierała, Tomasz; Leśniewska, Katarzyna

2014-01-01

In the presentation authors discuss the location-based factors’ impact on accommodation prices. The aim of the presentation is to compare the results of qualitative and quantitative research on location-based determinants of accommodation prices in Lodz Metropolitan Area (Poland). The authors employ methodological triangulation (Yeung 2000), both to explore statistical significance of location-based determinants of accommodation prices, and to present managerial opinions about the influence o...

Photorefractive keratectomy in refractive accommodative esotropia.

Science.gov (United States)

Bilgihan, K; Akata, F; Or, M; Hasanreisoğlu, B

1997-01-01

Photorefractive keratectomy (PRK) was performed on a 19-year-old man with hyperopic astigmatism and refractive accommodative esotropia. The patient was orthophoric while wearing spectacles, but had an esotropia of 30 prism dioptres at near and distance vision without spectacles. The best corrected visual acuity of the right eye was 20/50 and of the left eye was 20/20. The excessive accommodative convergence of the patient was eliminated by correcting the hyperopic refractive error by performing PRK, and the patient became orthophoric after the treatment.

The Northwest Passage Dispute

DEFF Research Database (Denmark)

Burke, Danita Catherine

2018-01-01

This is an article written for the Oxford Research Group "Sustainable Security" series. It gives an overview of the dispute of the Northwest Passage and discusses factors which will contribute to the evolution of the dispute in the 21st century. This short contribution summarizes and adds to the ...... to the research recently published by the author through Palgrave Macmillan, Danita Catherine Burke, 2018, International Disputes and Cultural Ideas in the Canadian Arctic...

The rate of change of vergence-accommodation conflict affects visual discomfort.

Science.gov (United States)

Kim, Joohwan; Kane, David; Banks, Martin S

2014-12-01

Stereoscopic (S3D) displays create conflicts between the distance to which the eyes must converge and the distance to which the eyes must accommodate. Such conflicts require the viewer to overcome the normal coupling between vergence and accommodation, and this effort appears to cause viewer discomfort. Vergence-accommodation coupling is driven by the phasic components of the underlying control systems, and those components respond to relatively fast changes in vergence and accommodative stimuli. Given the relationship between phasic changes and vergence-accommodation coupling, we examined how the rate of change in the vergence-accommodation conflict affects viewer discomfort. We used a stereoscopic display that allows independent manipulation of the stimuli to vergence and accommodation. We presented stimuli that simulate natural viewing (i.e., vergence and accommodative stimuli changed together) and stimuli that simulate S3D viewing (i.e., vergence stimulus changes but accommodative stimulus remains fixed). The changes occurred at 0.01, 0.05, or 0.25 Hz. The lowest rate is too slow to stimulate the phasic components while the highest rate is well within the phasic range. The results were consistent with our expectation: somewhat greater discomfort was experienced when stimulus distance changed rapidly, particularly in S3D viewing when the vergence stimulus changed but the accommodative stimulus did not. These results may help in the generation of guidelines for the creation and viewing of stereo content with acceptable viewer comfort.

Gender Differences in Implicit and Explicit Memory for Affective Passages

Science.gov (United States)

Burton, Leslie A.; Rabin, Laura; Vardy, Susan Bernstein.; Frohlich, Jonathan; Wyatt, Gwinne; Dimitri, Diana; Constante, Shimon; Guterman, Elan

2004-01-01

Thirty-two participants were administered 4 verbal tasks, an Implicit Affective Task, an Implicit Neutral Task, an Explicit Affective Task, and an Explicit Neutral Task. For the Implicit Tasks, participants were timed while reading passages aloud as quickly as possible, but not so quickly that they did not understand. A target verbal passage was…

Space Station Freedom - Accommodation for technology R&D

Science.gov (United States)

Holt, Alan C.

1989-01-01

The paper examines the features of the accommodation equipment designed for the candidate technology payloads of the Space Station, which include magnetic plasma thruster systems and a hypothetical advanced electromagnetic propulsion system utilizing high-temperature superconductivity materials. The review of the accommodation-equipment concepts supports the assumption that some propulsion technologies can be tested on the Space Station while being attached externally to the station's truss structure. For testing technologies with inherent operation or performance hazards, space platforms and smaller free-flyers coordinated with the Space Station can be used. Diagrams illustrating typical accommodation equipment configurations are included.

Trapped Ion Quantum Computation by Adiabatic Passage

International Nuclear Information System (INIS)

Feng Xuni; Wu Chunfeng; Lai, C. H.; Oh, C. H.

2008-01-01

We propose a new universal quantum computation scheme for trapped ions in thermal motion via the technique of adiabatic passage, which incorporates the advantages of both the adiabatic passage and the model of trapped ions in thermal motion. Our scheme is immune from the decoherence due to spontaneous emission from excited states as the system in our scheme evolves along a dark state. In our scheme the vibrational degrees of freedom are not required to be cooled to their ground states because they are only virtually excited. It is shown that the fidelity of the resultant gate operation is still high even when the magnitude of the effective Rabi frequency moderately deviates from the desired value.

A meta-analysis of family accommodation and OCD symptom severity.

Science.gov (United States)

Wu, Monica S; McGuire, Joseph F; Martino, Charitie; Phares, Vicky; Selles, Robert R; Storch, Eric A

2016-04-01

Family accommodation in obsessive-compulsive disorder (OCD) is characterized by myriad behaviors, such as modifying family routines, facilitating avoidance, and engaging in compulsions to reduce obsessional distress. It has been linked to various deleterious outcomes including increased functional impairment and poorer treatment response for OCD. Although extant literature suggests a linear relationship between family accommodation and OCD symptom severity, the magnitude and statistical significance of this association has been inconsistent across studies, indicating that moderators may be influencing this relationship. The present study examined this relationship using meta-analytic techniques, and investigated sample-dependent (age, gender, comorbid anxiety/mood disorders) and methodological (administration method and number of items used in family accommodation measure, informant type, sample size, publication year) moderators. Forty-one studies were included in the present meta-analysis, and the overall effect size (ES) for the correlation between family accommodation and OCD symptom severity was moderate (r=.42). Moderator analyses revealed that the number of items on the family accommodation scale moderated the ES. No other sample-dependent or methodological characteristics emerged as moderators. In addition to being the first systematic examination of family accommodation moderators, these results highlight the moderate relationship between family accommodation and OCD severity that is influenced by measurement scales. Findings may be used to guide clinical care and inform future investigations by providing a more nuanced understanding of family accommodation in OCD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Introducing a open-quote modular close-quote approach to fish screen installation

International Nuclear Information System (INIS)

Taft, E.P.; Winchell, F.C.; Cook, T.C.; Sullivan, C.W.

1992-01-01

A new fish screen design-the modular inclined screen-promises to offer a versatile and cost-effective solution for fish protection in many situation. In an effort to provide the hydroelectric industry with more cost-effective alternatives to existing fish screen designs, the Electric Power Research Institute (EPRI) recently has undertaken several research projects. One focus of EPRI's research has been on the development and testing of high-velocity fish screens. This program has led to the development of a new screening concept, which shows promise for providing effective protection for a wide range of fish species at hydro plants, steam generating facilities, and irrigation diversions. The concept, known as the Modular Inclined Screen (MIS), currently is being evaluated in laboratory studies prior to field application. The screen is of open-quotes modularclose quotes design so as to provide the flexibility necessary for application at a broad range of water intakes. The module is suitable for installation in penstocks, canals, and head pond intakes. The MIS module consists of an entrance with a trashrack, dewatering stoplog slots, an inclined wedgewire screen set at a shallow angle of 10 to 20 degrees to the flow, and a bypass for diverting fish to a transport pipe. The screen is mounted on a pivot shaft so that it can be cleaned via rotation and backflushing. The module is completely enclosed, and is designed to operate at water velocities ranging from 2 to 10 feet per second depending on the fish species and life stages to be protected. Laboratory studies are under way to evaluate the design configuration that yields the best hydraulic conditions for safe fish passage, and the biological effectiveness of this design in diverting selected fish species to the bypass

Gain and movement time of convergence-accommodation in preschool children.

Science.gov (United States)

Suryakumar, R; Bobier, W R

2004-11-01

Convergence-accommodation is the synkinetic change in accommodation driven by vergence. A few studies have investigated the static and dynamic properties of this cross-link in adults but little is known about convergence-accommodation in children. The purpose of this study was to develop a technique for measuring convergence-accommodation and to study its dynamics (gain and movement time) in a sample of pre-school children. Convergence-accommodation measures were examined on thiry-seven normal pre-school children (mean age = 4.0 +/- 1.31 yrs). Stimulus CA/C (sCA/C) ratios and movement time measures of convergence-accommodation were assessed using a photorefractor while subjects viewed a DOG target. Repeated measures were obtained on eight normal adults (mean age = 23 +/- 0.2 yrs). The mean sCA/C ratios and movement times were not significantly different between adults and children (0.10 D/Delta [0.61 D/M.A.], 743 +/- 70 ms and 0.11 D/Delta [0.50 D/M.A.], 787 +/- 216 ms). Repeated measures on adults showed a non-significant mean difference of 0.001 D/Delta. The results suggest that the possible differences in crystalline lens (plant) characteristics between children and adults do not appear to influence convergence-accommodation gain or duration.

Accommodation Paralysis after Pheniramine Maleate Injection: A Case Report.

Science.gov (United States)

Bingol Kiziltunc, Pinar; Atilla, Huban; Yalcindag, F Nilufer

2013-01-01

We present a case in which Gilbert syndrome was diagnosed following a neuro-ophthalmic complaint. Adverse effects of drugs as well as various systemic, neurological, and local ocular pathologies can cause accommodative insufficiency and loss of accommodation. A 29-year-old man was admitted to an ophthalmology department with blurred vision and diagnosed as suffering from acute accommodation paralysis. He had a history of being given a pheniramine maleate injection for pruritus 20 days previously. Symptoms began immediately following the injection. After systemic evaluation and laboratory tests, he was diagnosed as having Gilbert syndrome. His complaints and symptoms recovered in approximately a further 10 days. Metabolism of pheniramine maleate can be impaired in Gilbert syndrome and anticholinergic effects can cause accommodation paralysis.

Rediscovering Rites of Passage: Education, Transformation, and the Transition to Sustainability

Directory of Open Access Journals (Sweden)

David Adam Lertzman

2002-01-01

Full Text Available This paper focuses on rites of passage as a model for wilderness programs. It draws on my experience in the field, particularly with Native youth in a community-based program called "Rediscovery." The Rediscovery program is discussed, along with concepts of traditional indigenous knowledge and education. Foundational concepts of rites of passage are described in terms of their relevance to youth, outdoor education, and the Rediscovery program in particular. Using Rediscovery as a model, rites of passage are put forward as an educational process for youth from various cultural backgrounds. In this context, the purpose of education is to cultivate self-knowledge and to foster core personal development: the making of whole human beings. The paper closes with a reflection on my work with traditional indigenous people and the significance of rites of passage for education, cultural transformation, and the transition to ecological sustainability.

Evaluation of Accommodation Companies Recreation Activities in İstanbul

OpenAIRE

Aslı ALBAYRAK

2012-01-01

Recreation activities represent quality of company, image and attractiveness for both staying guests and day use guests. At the same time recreation can be important income source for accommodation companies. This study investigate the web page of 82 five star accommodation company in Istanbul from the side of recreation activities. At the end of the study find that most of accommodation company don't have in place recreation activities, recreation tab and representation about activities in t...

A NOVELTY MODEL OF ONLINE ACCOMMODATION PRESENTATION AND DISCOVERY

OpenAIRE

Sjekavica, Tomo; Žitnik, Marjan; Miličević, Mario

2017-01-01

Extreme expansion of digital technologies and social networks in recent years has had a huge impact on the travel market and online tourism. Along with the digitalization of tourism and travel business, every day more and more accommodation bookings take place online. Most popular online travel web sites are commonly charging provision for the accommodation booking and don't allow direct contact with the accommodation owners. Today tourists demand more for their money, so they are more likely...

New Concepts in Fish Ladder Design, Part I of IV, Summary Report, 1982-1984 Final Project Report.

Energy Technology Data Exchange (ETDEWEB)

Orsborn, John F.

1985-08-01

The report looks at the most active periods of fishway research since 1938 as background for a project to apply fundamental fluid and bio-mechanics to fishway design, and develop more cost effective fish passage facilities with primary application to small scale hydropower facilities. Also discussed are new concepts in fishway design, an assessment of fishway development and design, and an analysis of barriers to upstream migration. (ACR)

Principle and design of hatch operation system for fish migrating upstream-downstream of the discharge sill

Directory of Open Access Journals (Sweden)

Răzvan G.Voicu

2016-09-01

Full Text Available To improve fish migration and restore local lotic ecosystems, it is necessary to consider the various current hydro-construction methods. There have been partial successes in systems that improve fish passage over various obstacles but new approaches that present more efficient solutions and international collaboration among specialists are required. This article deals with European themes of great interest; issues related to interruption of longitudinal connectivity in heavily modified water courses, and improving the ecological status of damaged lotic systems, with the goal of achieving the environmental objectives set forth by the Water Framework Directive 2000/60/EC (WFD and the national legislative framework regarding water policy (which reflects the European directives Water Law no. 107, with subsequent amendments, NT No. / 2006 OM 1163/2007, and discusses the obligation to ensure that construction works protect fish migration to maintain ecological balance in the reservoirs. It is possible to use this system in almost any fish-bearing stream, both upstream and downstream of maximum circulation, which makes the system an excellent solution for assisting and improving migration.

Comparing family accommodation in pediatric obsessive-compulsive disorder, anxiety disorders, and nonanxious children.

Science.gov (United States)

Lebowitz, Eli R; Scharfstein, Lindsay A; Jones, Johnna

2014-12-01

Family accommodation describes ways in which parents modify their behavior to help a child avoid or alleviate distress caused by emotional disorders. Accommodation is associated with increased symptom severity, lower functioning, and poorer treatment outcomes. Accommodation is prevalent in childhood obsessive-compulsive disorder (OCD) and anxiety disorders (ADs) but no studies have compared accommodation in these groups or compared them to healthy controls to ascertain if accommodation is prevalent in the general population. This study addresses these gaps by comparing patterns of accommodation, factors that maintain accommodation, and its relation to symptom severity in OCD and AD, relative to healthy controls. We directly compared reports of accommodation to childhood OCD (N = 26) and AD (N = 31), and a comparison group of nonanxious (NA) children (N = 30). Mothers completed measures of accommodation (Family Accommodation Scale (FAS)/Family Accommodation Scale-Anxiety (FASA)), anxiety (Screen for Childhood Anxiety Related Emotional Disorders-Parent Report (SCARED-PR)), and OCD (Children's Yale-Brown Obsessive Compulsive Scale (CYBOCS)). Family accommodation is prevalent among mothers of children with OCD and AD. Few differences were found between the two clinical groups who reported more accommodation (F[2,84] = 23.411, P anxiety in AD (r = .426, P = .017) and OCD (r = .465, P = .017), but not in the NA group. Findings highlight family accommodation as a phenomenon that applies broadly and in a similar manner to children with AD and OCD. Evaluating accommodation provides useful information for clinical care and is an important part of the assessment of children with AD and OCD. © 2014 Wiley Periodicals, Inc.

Convergence and Accommodation Development Is Preprogrammed in Premature Infants.

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Horwood, Anna M; Toor, Sonia S; Riddell, Patricia M

2015-08-01

This study investigated whether vergence and accommodation development in preterm infants is preprogrammed or is driven by experience. Thirty-two healthy infants, born at mean 34 weeks gestation (range, 31.2-36 weeks), were compared with 45 healthy full-term infants (mean 40.0 weeks) over a 6-month period, starting at 4 to 6 weeks postnatally. Simultaneous accommodation and convergence to a detailed target were measured using a Plusoptix PowerRefII infrared photorefractor as a target moved between 0.33 and 2 m. Stimulus/response gains and responses at 0.33 and 2 m were compared by both corrected (gestational) age and chronological (postnatal) age. When compared by their corrected age, preterm and full-term infants showed few significant differences in vergence and accommodation responses after 6 to 7 weeks of age. However, when compared by chronological age, preterm infants' responses were more variable, with significantly reduced vergence gains, reduced vergence response at 0.33 m, reduced accommodation gain, and increased accommodation at 2 m compared to full-term infants between 8 and 13 weeks after birth. When matched by corrected age, vergence and accommodation in preterm infants show few differences from full-term infants' responses. Maturation appears preprogrammed and is not advanced by visual experience. Longer periods of immature visual responses might leave preterm infants more at risk of development of oculomotor deficits such as strabismus.

Effect of passage number on cellular response to DNA-damaging agents: Cell survival and gene expression

International Nuclear Information System (INIS)

Chang-Liu, C.M.; Woloschak, G.E.

1997-01-01

The effect of different passage numbers on plating efficiency, doubling time, cell growth, and radiation sensitivity was assessed in Syrian hamster embryo (SHE) cells. Changes in gene expression after UV or γ-ray irradiation at different passage numbers were also examined. The SHE cells were maintained in culture medium for up to 64 passages. Cells were exposed to 60 Co γ rays or 254-nm UV radiation. Differential display of cDNAs and northern blots were used for the study of gene expression. With increasing passage number, SHE cells demonstrated decreased doubling time, increased plating efficiency, and a decreased yield in the number of cells per plate. Between passages 41 and 48 a crisis period was evident during which time cell growth in high serum was no longer optimal, and serum concentrations were reduced to maintain cell growth. Sensitivity to ionizing radiation was no different between early- and intermediate-passage cells. However, after UV exposure at low passages (passage 3), confluent cells were more sensitive to the killing effects of UV than were log-phase cells. At intermediate passages (passages 43, 48), confluent cells were slightly more radioresistant than were log-phase cells. By passage 64, however, both confluent and log-phase cells showed similar patterns of UV sensitivity. Expression of γ-actin, PCNA, and p53 transcripts did not change following UV exposure. p53 mRNA was induced following γ-ray exposure of the intermediate (passage 45) epithelial cells. The observed differences in radiation sensitivity associated with increasing passage number may be influenced by radiation-induced gene expression. The authors are conducted experiments to identify these genes

Different effects of resveratrol on early and late passage mesenchymal stem cells through β-catenin regulation

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Yoon, Dong Suk; Choi, Yoorim; Choi, Seong Mi [Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul (Korea, Republic of); Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul (Korea, Republic of); Park, Kwang Hwan [Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, Jin Woo, E-mail: ljwos@yuhs.ac [Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul (Korea, Republic of); Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul (Korea, Republic of)

2015-11-27

Resveratrol is a sirtuin 1 (SIRT1) activator and can function as an anti-inflammatory and antioxidant factor. In mesenchymal stem cells (MSCs), resveratrol enhances the proliferation and differentiation potential and has an anti-aging effect. However, contradictory effects of resveratrol on MSC cultures have been reported. In this study, we found that resveratrol had different effects on MSC cultures according to their cell passage and SIRT1 expression. Resveratrol enhanced the self-renewal potential and multipotency of early passage MSCs, but accelerated cellular senescence of late passage MSCs. In early passage MSCs expressing SIRT1, resveratrol decreased ERK and GSK-3β phosphorylation, suppressing β-catenin activity. In contrast, in late passage MSCs, which did not express SIRT1, resveratrol increased ERK and GSK-3β phosphorylation, activating β-catenin. We confirmed that SIRT1-deficient early passage MSCs treated with resveratrol lost their self-renewal potential and multipotency, and became senescent due to increased β-catenin activity. Sustained treatment with resveratrol at early passages maintained the self-renewal potential and multipotency of MSCs up to passage 10. Our findings suggest that resveratrol can be effectively applied to early passage MSC cultures, whereas parameters such as cell passage and SIRT1 expression must be taken into consideration before applying resveratrol to late passage MSCs. - Highlights: • Resveratrol enhances self-renewal potential and multipotency of early passage MSCs. • Resveratrol accelerates the cellular senescence of late passage MSCs. • The effects of resveratrol on MSCs are dependent on the presence of SIRT1. • SIRT1 modulates ERK/GSK-3β/β-catenin signaling. • Sustained resveratrol treatment maintains MSC stemness up to P10.

Branchial cymothoids infesting the marine food fishes of Malabar coast.

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Panakkool-Thamban, Aneesh; Ameri Kottarathil, Helna; Kappalli, Sudha

2016-12-01

Occurrence of cymothoid isopods parasitizing the branchial chamber of marine food fishes along the Malabar coast was investigated. Live and fresh fishes collected from the Ayyikkara fish landing center (Lat. 11°51'N, Long. 75°22'E; Malabar coast, India) were subjected to the thorough observation for the presence of branchial cymothoids for 3 consecutive years (November 2009-November 2012). Among the recovered cymothoids, 11 species were branchial residents belonging to 6 genera; the species include Agarna malayi, Catoessa gruneri, C. boscii, Joryma hilsae, J. brachysoma, J. engraulidis, J. sawayah, Mothocya collettei, M. renardi, Norileca indica and Ryukyua circularis ; highest prevalence being exhibited by two species of Mothocya , ( M. renardi and M. collettei ) parasitizing the belonidaen fishes, Strongylura leiura (92.15 %) and Tylosurus crocodilus crocodilus (87.2 %) respectively. Except Mothocya species, which preferred the branchial floor for infestation, all recovered branchial cymothoids were found attached the inner wall of the operculum. In several instances, the parasites appeared in male-female pairs, one in each branchial cavity. Ovigerous female members of all species of branchial cymothoids except R. circularis showed remarkable bending either towards left or right depending on whether they are located in right or left branchial cavity of their respective host fishes. The deleterious effects of parasitization by all recovered branchial cymothoids include the formation of a pit like depression in the branchial chamber and atrophy of the gill filament; the damage was more pronounced in the gill cavity of parasitized host fishes where the ovigerous female member was accommodated.

Disability disclosure and workplace accommodations among youth with disabilities.

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Lindsay, Sally; Cagliostro, Elaine; Leck, Joanne; Shen, Winny; Stinson, Jennifer

2018-03-20

Many youths with disabilities find it challenging to disclose their medical condition and request workplace accommodations. Our objective was to explore when and how young people with disabilities disclose their condition and request workplace accommodations. We conducted 17 in-depth interviews (11 females, six males) with youth with disabilities aged 15-34 (mean age 26). We analyzed our data using an interpretive, qualitative, and thematic approach. Our results showed the timing of when youth disclosed their disability to their employer depended on disability type and severity, comfort level, type of job, and industry. Youth's strategies and reasons for disclosure included advocating for their needs, being knowledgeable about workplace rights, and accommodation solutions. Facilitators for disclosure included job preparation, self-confidence, and self-advocacy skills, and having an inclusive work environment. Challenges to disability disclosure included the fear of stigma and discrimination, lack of employer's knowledge about disability and accommodations, negative past experiences of disclosing, and not disclosing on your own terms. Our findings highlight that youth encounter several challenges and barriers to disclosing their condition and requesting workplace accommodations. The timing and process for disclosing is complex and further work is needed to help support youth with disclosing their condition. Implications for rehabilitation Clinicians, educators, and employers should emphasize the importance of mentoring and leadership programs to give youth the confidence and self-advocacy skills needed to disclose and ask for accommodations in the workplace. Clinicians should advocate for the inclusion of youth with disabilities in the workforce and educate employers on the importance of doing so. Youth with disabilities need more opportunities for employment training and particularly how to disclose their disability and request workplace accommodations.

Stationary Probability and First-Passage Time of Biased Random Walk

International Nuclear Information System (INIS)

Li Jing-Wen; Tang Shen-Li; Xu Xin-Ping

2016-01-01

In this paper, we consider the stationary probability and first-passage time of biased random walk on 1D chain, where at each step the walker moves to the left and right with probabilities p and q respectively (0 ⩽ p, q ⩽ 1, p + q = 1). We derive exact analytical results for the stationary probability and first-passage time as a function of p and q for the first time. Our results suggest that the first-passage time shows a double power-law F ∼ (N − 1) γ , where the exponent γ = 2 for N < |p − q| −1 and γ = 1 for N > |p − q| −1 . Our study sheds useful insights into the biased random-walk process. (paper)

Work accommodations and natural supports for maintaining employment.

Science.gov (United States)

Corbière, Marc; Villotti, Patrizia; Lecomte, Tania; Bond, Gary R; Lesage, Alain; Goldner, Elliot M

2014-06-01

Job tenure for people with severe mental disorders, even for those enrolled in supported employment programs, is typically brief. Few studies to date have investigated the relationship between accommodations and natural supports available in the workplace, and job tenure for this population. The main objectives of this study were to develop and to validate a new measure to describe work accommodations and natural supports available in the workplace and to determine which of them are significantly related to job tenure for participants enrolled in supported employment services. In total, 124 people with a severe mental disorder enrolled in supported employment programs and who obtained only one competitive employment at the 9-month follow-up answered the Work Accommodation and Natural Support Scale (WANSS). They also provided information regarding their disclosure (or non-) of mental disorders in the workplace and the length of their job tenure. Confirmatory factor analysis conducted on the WANSS showed 40 items distributed on 6 dimensions (e.g., Schedule flexibility). Correlation results showed that disclosure was significantly related to the number of work accommodations and natural supports available in the workplace. Survival analyses indicated that one WANSS dimension was more salient in predicting job tenure: Supervisor and coworker supports. The WANSS is a valid and useful tool to assess work accommodations and natural supports available in the workplace that employment specialists could use in their practice.

The influence of family accommodation on pediatric hospital experience in Canada.

Science.gov (United States)

Franck, Linda S; Ferguson, Deron; Fryda, Sarah; Rubin, Nicole

2017-08-15

The goals of our study were to describe the types of family accommodation for parents of hospitalized children and to examine their influence on the pediatric hospital experience. This multi-site cohort survey included 10 hospitals in Ontario Province, Canada. Participants were parents of inpatient children (n = 1240). Main outcome measures included ratings of three parent-reported measures of hospital experience: overall hospital experience; willingness to recommend the hospital to family or friends; and how much the accommodation type helped parent stay involved in their child's hospital care. Parents most often stayed in the child's room (74.7%), their own home (12.3%), hotel (4.0%) or a Ronald McDonald House (3.0%). Accommodation varied based on hospital, parent and child factors. Length of stay and the child's health status were significant predictors for overall hospital experience and recommending the hospital to family or friends, but accommodation type was not. Families who stayed at a Ronald McDonald House reported greater involvement in their child's care compared with other accommodation types (odds ratio: 1.54-20.73 for contrasted accommodation types). Use of different overnight accommodations for families of hospitalized pediatric patients in Canada is similar to a previous report of U.S. family hospital accommodations. In contrast to the previous U.S. findings, Canadian hospital experience scores were lower and accommodation type was not a significant predictor of overall hospital experience or willingness to recommend the hospital. In Canada, as in the U.S., families who stayed at a Ronald McDonald House reported that this accommodation type significantly improved their ability to be involved in their child's care.

Effect of different reading interfaces and conditions on the accommodation response

Directory of Open Access Journals (Sweden)

Xiao-Feng Wang

2016-04-01

Full Text Available AIM:To compare the difference of accommodation response under the variety reading conditions including computer screen, mobile phone screen and printed texts. The investigation also included the accommodation response under these conditions with different distances, brightness, dynamic and static testing status. METHODS:Thirty volunteer subjects were included with normal vision function. The reading target on computer screen, mobile screen and paper were used, respectively. Grand Seiko WAM 5500 infrared automatic refractometer was applied to measure accommodation response. The influence of different reading conditions on accommodation was compared using variance analysis with SPSS17.0.RESULTS:Accommodation lag under the computer screen with high brightness was 0.52±0.24D, that under papers was 0.73±0.28D, that under mobile phone was 0.72±0.29D. Accommodation lag under the computer screen with high brightness was less than that under mobile phones and paper, the differences were statistically significant(PCONCLUSION:Accommodation lag under the computer screen with high brightness is relatively smaller than that under mobile phone or paper. There is no significant difference between those under phones and paper. With the brightness of computers in a certain range, there is no effect for accommodation response.

Attention-deficit/hyperactivity disorder children exhibit an impaired accommodative response.

Science.gov (United States)

Redondo, Beatriz; Vera, Jesús; Molina, Rubén; García, José Antonio; Ouadi, Miriam; Muñoz-Hoyos, Antonio; Jiménez, Raimundo

2018-05-01

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common paediatric neurobehavioural disorders causing multiple functional impairments in children. Based on the relationship between the neural system that controls attention and ocular dynamics, the present study compares the magnitude and variability of accommodation between a group of non-medicated ADHD children and an age-matched control group. The magnitude and variability of the accommodative response were objectively measured in 36 children using the WAM-5500 autorefractometer for 90 consecutive seconds at three static viewing distances (500, 40, and 20 cm). Participants were divided into ADHD (n = 18) or control (n = 18) groups based on clinically validated criteria. Children with ADHD exhibited higher lags of accommodation (p = 0.024), increasing at closer viewing distances, in comparison to the control group. Marginal statistical differences were found for the variability of accommodation (p = 0.066), with the ADHD group showing a trend towards higher variability. Our analysis showed that the magnitude and variability of accommodation did not vary over time between groups (p > 0.05). Our data suggest that children with ADHD have a less accurate accommodative response. These results provide a new ocular index that could help to clarify the relationship between accommodative response and attentional deficits, which could have a direct impact on the academic, cognitive, and visual performance of ADHD children.

77 FR 28253 - Safety Zone; America's Cup World Series, East Passage, Narragansett Bay, RI

Science.gov (United States)

2012-05-14

...-AA00 Safety Zone; America's Cup World Series, East Passage, Narragansett Bay, RI AGENCY: Coast Guard... navigable waters of the East Passage, Narragansett Bay, Rhode Island, during the America's Cup World Series... rulemaking (NPRM) entitled ``Safety Zones; America's Cup World Series, East Passage, Narragansett Bay, RI...

Guidelines for Providing Accommodations Using CASAS Assessment for Learners with Disabilities

Science.gov (United States)

CASAS - Comprehensive Adult Student Assessment Systems (NJ1), 2005

2005-01-01

These guidelines address methods for administering Comprehensive Adult Student Assessment System (CASAS) assessments using accommodations for learners with documented disabilities. The suggested accommodations for disability categories include provisions for: (1) Accommodations in test administration procedures; and (2) Use of appropriate CASAS…

Passage times of asymmetric anomalous walks with multiple paths

International Nuclear Information System (INIS)

Caceres, Manuel O; Insua, G Liliana

2005-01-01

We investigate the transient and the long-time behaviour of asymmetric anomalous walks in heterogeneous media. Two types of disorder are worked out explicitly: weak and strong disorder; in addition, the occurrence of disordered multiple paths is considered. We calculate the first passage time distribution of the associated stochastic transport process. We discuss the occurrence of the crossover from a power law to an exponential decay for the long-time behaviour of the distribution of the first passage times of disordered biased walks

Analysis of Environmental Issues Related to Small-Scale Hydroelectric Development IV: Fish Mortality Resulting From Turbine Passage

Energy Technology Data Exchange (ETDEWEB)

Turbak, Susan C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Reichle, Donna R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shriner, Carole R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

1981-01-01

The purpose of this report is to provide summary information for use by potential developers and regulators of small-scale hydroelectric projects (defined as existing dams that can be retrofitted to a total site capacity of ≤30 MW), where turbine-related mortality of fish is a potential issue affecting site-specific development. Mitigation techniques for turbine-related mortality are not covered in this report.

Family Accommodation in Obsessive-Compulsive Disorder: A Study on Associated Variables

Directory of Open Access Journals (Sweden)

Teresa Cosentino

2015-10-01

Full Text Available The present study aimed to examine family accommodation in relatives of obsessive-compulsive disease (OCD patients. Accommodation was assessed in a sample of 31 relatives of OCD patients by means of the Family Accommodation Scale. Other variables measured as predictors of accommodation were the tendency of a family member to feel guilty, sensitivity to guilt, anxiety sensitivity and the prevalence of a passive communication style. Accommodation was found to be rather widespread in the family members who took part in our study, and they tended to show more accommodation the greater their sensitivity to guilt and the stable tendency to experience this emotion as well as anxiety sensitivity and a passive communication style. Multiple linear regression analyses showed that, among the variables considered, the family member’s sensitivity to guilt is the only factor which can predict accommodation with regard to the patient’s demands for involvement. On the other hand, the small number of family members in the sample and the lack of clinical data on patients (such as the severity, typology and duration of their obsessive-compulsive disorder pose limits to the generalizability of the results and point to the need for further research.

Variations in accommodation and convergence responses in a minimally controlled photorefractive setting.

Science.gov (United States)

Horwood, A M; Turner, J E; Houston, S M; Riddell, P M

2001-11-01

A remote haploscopic photorefractor, designed for assessment of accommodation and convergence in infants and clinical groups, was used to determine heterophoria accommodative convergence/accommodation (AC/A) ratios in normal naïve adults. These were compared with conventional clinical measures. Twenty-one naïve subjects were used to compare occluded and unoccluded prism cover test responses with the remote haploscopic photorefractor using a text and picture target. Although luminance was generally low for both targets, binocular vergences were appropriate for target demand in both studies. Binocular accommodation showed greater lag for the highest target accommodative demand and the less demanding target. Occlusion not only reduced vergence response, but also frequently caused a marked reduction in accommodation, especially to the picture target. Normal mean AC/A values were found, but with wide variations between individual subjects. Although mean accommodation, vergence, and AC/A values were comparable with published data, we suggest that in these conditions using naïve subjects, accommodation is frequently inaccurate, especially on occlusion, without concomitant loss of vergence, at least at low light levels. Accommodative convergence may play a less important part in, and other cues contribute more to, the near reflex than has been previously suggested.

Differentiation potential of STRO-1+ dental pulp stem cells changes during cell passaging

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Wang Ruoning

2010-05-01

Full Text Available Abstract Background Dental pulp stem cells (DPSCs can be driven into odontoblast, osteoblast, and chondrocyte lineages in different inductive media. However, the differentiation potential of naive DPSCs after serial passaging in the routine culture system has not been fully elucidated. Results DPSCs were isolated from human/rat dental pulps by the magnetic activated cell sorting based on STRO-1 expression, cultured and passaged in the conventional culture media. The biological features of STRO-1+ DPSCs at the 1st and 9th passages were investigated. During the long-term passage, the proliferation ability of human STRO-1+ DPSCs was downregulated as indicated by the growth kinetics. When compared with STRO-1+ DPSCs at the 1st passage (DPSC-P1, the expression of mature osteoblast-specific genes/proteins (alkaline phosphatase, bone sialoprotein, osterix, and osteopontin, odontoblast-specific gene/protein (dentin sialophosphoprotein and dentin sialoprotein, and chondrocyte-specific gene/protein (type II collagen was significantly upregulated in human STRO-1+ DPSCs at the 9th passage (DPSC-P9. Furthermore, human DPSC-P9 cells in the mineralization-inducing media presented higher levels of alkaline phosphatase at day 3 and day 7 respectively, and produced more mineralized matrix than DPSC-P9 cells at day 14. In vivo transplantation results showed that rat DPSC-P1 cell pellets developed into dentin, bone and cartilage structures respectively, while DPSC-P9 cells can only generate bone tissues. Conclusions These findings suggest that STRO-1+ DPSCs consist of several interrelated subpopulations which can spontaneously differentiate into odontoblasts, osteoblasts, and chondrocytes. The differentiation capacity of these DPSCs changes during cell passaging, and DPSCs at the 9th passage restrict their differentiation potential to the osteoblast lineage in vivo.

Cultural value orientations, internalized homophobia, and accommodation in romantic relationships.

Science.gov (United States)

Gaines, Stanley O; Henderson, Michael C; Kim, Mary; Gilstrap, Samuel; Yi, Jennifer; Rusbult, Caryl E; Hardin, Deletha P; Gaertner, Lowell

2005-01-01

In the present study, we examined the impact of cultural value orientations (i.e., the personally oriented value of individualism, and the socially oriented values of collectivism, familism, romanticism, and spiritualism) on accommodation (i.e., voice and loyalty, rather than exit and neglect, responses to partners' anger or criticism) in heterosexual and gay relationships; and we examined the impact of internalized homophobia (i.e., attitudes toward self, other, and disclosure) on accommodation specifically in gay relationships. A total of 262 heterosexuals (102 men and 162 women) and 857 gays (474 men and 383 women) participated in the present study. Consistent with hypotheses, among heterosexuals and gays, socially oriented values were significantly and positively related to accommodation (whereas the personally oriented value of individualism was unrelated to accommodation); and among gays in particular, internalized homophobia was significantly and negatively related to accommodation. Implications for the study of heterosexual and gay relationships are discussed.

Investigations of entrainment mortality among larval and juvenile fishes using a Power Plant Simulator

International Nuclear Information System (INIS)

Cada, G.F.; Suffern, J.S.; Kumar, K.D.; Solomon, J.A.

1980-01-01

A Power Plant Simulator (PPS) was constructed at the Oak Ridge National Laboratory to examine the component sources of entrainment mortality. This experimental apparatus circulates temperature-controlled water through a closed loop consisting of a pump, a condenser bundle, and vertically adjustable piping. Larval bluegill, channel catfish, carp, largemouth bass, and smallmouth bass and juvenile bluegill and mosquitofish were exposed to different combinations of pump speed and water temperatures in the PPS. Wide differences among species in their sensitivity to pipe and condenser passage were observed. For most of the species tested, short-term conditional mortalities resulting from the physical stresses of pipe and condenser passage increased with ΔT and/or pumping rate. Pump passage was not a major source of physical damage, and no clear relationship was found between pump efficiency and mortality. Susceptibility to physical stresses associated with entrainment was inversely related to the size of the entrained organisms. Delayed mortality frequently occurred among fishes exposed to stresses in the PPS. However, delayed mortality estimates in these experimental groups were significantly greater than corresponding values in handling control groups in only 15 of 64 comparisons. Like short-term mortalities, relatively higher delayed mortalities were often observed for the smaller species tested

Amplitude of Accommodation and its Relation to Refractive Errors

Directory of Open Access Journals (Sweden)

Abraham Lekha

2005-01-01

Full Text Available Aims: To evaluate the relationship between amplitude of accommodation and refractive errors in the peri-presbyopic age group. Materials and Methods: Three hundred and sixteen right eyes of 316 consecutive patients in the age group 35-50 years who attended our outpatient clinic were studied. Emmetropes, hypermetropes and myopes with best-corrected visual acuity of 6/6 J1 in both eyes were included. The amplitude of accommodation (AA was calculated by measuring the near point of accommodation (NPA. In patients with more than ± 2 diopter sphere correction for distance, the NPA was also measured using appropriate soft contact lenses. Results: There was a statistically significant difference in AA between myopes and hypermetropes ( P P P P P P >0.5. Conclusion: Our study showed higher amplitude of accommodation among myopes between 35 and 44 years compared to emmetropes and hypermetropes

Family accommodation in obsessive-compulsive and anxiety disorders: a five-year update.

Science.gov (United States)

Lebowitz, Eli R; Panza, Kaitlyn E; Bloch, Michael H

2016-01-01

Family accommodation describes changes that individuals make to their behavior, to help their relative who is dealing with a psychiatric and/or psychological disorder(s), avoid or alleviate distress related to the disorder. Research on family accommodation has advanced rapidly. In this update we aim to provide a synthesis of findings from the past five years. A search of available, peer-reviewed, English language papers was conducted through PubMed and PsycINFO, cross referencing psychiatric disorders with accommodation and other family-related terms. The resulting 121 papers were individually reviewed and evaluated and the main findings were discussed. Family accommodation is common in obsessive-compulsive disorder (OCD) and in anxiety disorders, and manifests similarly across these disorders. Family accommodation is associated with more severe psychopathology and poorer clinical outcomes. Treatments have begun to focus on the reduction of family accommodation as a primary therapeutic goal and finally, neurobiological underpinnings of family accommodation are beginning to be investigated.

Formation of Hyaline Cartilage Tissue by Passaged Human Osteoarthritic Chondrocytes.

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Bianchi, Vanessa J; Weber, Joanna F; Waldman, Stephen D; Backstein, David; Kandel, Rita A

2017-02-01

When serially passaged in standard monolayer culture to expand cell number, articular chondrocytes lose their phenotype. This results in the formation of fibrocartilage when they are used clinically, thus limiting their use for cartilage repair therapies. Identifying a way to redifferentiate these cells in vitro is critical if they are to be used successfully. Transforming growth factor beta (TGFβ) family members are known to be crucial for regulating differentiation of fetal limb mesenchymal cells and mesenchymal stromal cells to chondrocytes. As passaged chondrocytes acquire a progenitor-like phenotype, the hypothesis of this study was that TGFβ supplementation will stimulate chondrocyte redifferentiation in vitro in serum-free three-dimensional (3D) culture. Human articular chondrocytes were serially passaged twice (P2) in monolayer culture. P2 cells were then placed in high-density (3D) culture on top of membranes (Millipore) and cultured for up to 6 weeks in chemically defined serum-free redifferentiation media (SFRM) in the presence or absence of TGFβ. The tissues were evaluated histologically, biochemically, by immunohistochemical staining, and biomechanically. Passaged human chondrocytes cultured in SFRM supplemented with 10 ng/mL TGFβ3 consistently formed a continuous layer of articular-like cartilage tissue rich in collagen type 2 and aggrecan and lacking collagen type 1 and X in the absence of a scaffold. The tissue developed a superficial zone characterized by expression of lubricin and clusterin with horizontally aligned collagen fibers. This study suggests that passaged human chondrocytes can be used to bioengineer a continuous layer of articular cartilage-like tissue in vitro scaffold free. Further study is required to evaluate their ability to repair cartilage defects in vivo.

Hyperelastic modelling of the crystalline lens: Accommodation and presbyopia

Science.gov (United States)

Lanchares, Elena; Navarro, Rafael; Calvo, Begoña

2012-01-01

Purpose The modification of the mechanical properties of the human crystalline lens with age can be a major cause of presbyopia. Since these properties cannot be measured in vivo, numerical simulation can be used to estimate them. We propose an inverse method to determine age-dependent change in the material properties of the tissues composing the human crystalline lens. Methods A finite element model of a 30-year-old lens in the accommodated state was developed. The force necessary to achieve full accommodation in a 30-year-old lens of known external geometry was computed using this model. Two additional numerical models of the lens corresponding to the ages of 40 and 50 years were then built. Assuming that the accommodative force applied to the lens remains constant with age, the material properties of nucleus and cortex were estimated by inverse analysis. Results The zonular force necessary to reshape the model of a 30-year-old lens from the accommodated to the unaccommodated geometry was 0.078 newton (N). Both nucleus and cortex became stiffer with age. The stiffness of the nucleus increased with age at a higher rate than the cortex. Conclusions In agreement with the classical theory of Helmholtz, on which we based our model, our results indicate that a major cause of presbyopia is that both nucleus and cortex become stiffer with age; therefore, a constant value of the zonular forces with aging does not achieve full accommodation, that is, the accommodation capability decreases.

Alternatives and passages

DEFF Research Database (Denmark)

Hansbøl, Mikala

2010-01-01

While much research into serious games focus on following teaching and/or learning activities, and particularly the human and institutional actors involved in these, the central actors of game based learning research (i.e. the games) seldom get much attention (unless the focus is so......-called "technological"). This brief positioning paper takes point of departure in an ongoing postdoc project following circulations and establishments of http://www.mingoville.com/ , which is a virtual universe with game based elements developed for beginning English teaching and learning.  The paper presents a Science...... and Technology Studies (STS) and Actor-Network-Theory (ANT) inspired approach to researching emerging passages between beginning English teaching and learning and Mingoville....

Europa Passage, Hamburg. Pumps ensure thermal comfort at all levels; Die Europa Passage in Hamburg. Pumpen sorgen fuer Komfort auf allen Ebenen

Energy Technology Data Exchange (ETDEWEB)

Teders, Klaus

2009-07-01

The Europa Passage at Hamburg is a new shopping mall located directly on the Binnenalster river. It was constructed in 2006 and has 30,000 m{sup 2} of shop floor on five levels, which makes it one of Germany's biggest shopping malls. It is frequented every day by up to 40,000 visitors and more than 50,000 visitors on saturdays. In order to ensure optimum comfort even in peak times, the passage is equipped with state-of-the-art technical facilities. Energy-efficient pumps ensure reliable supply of all technical facilities. (orig.)

Lens Accommodation, Ocular Convergence and the Brain(Physiology of Vision)

OpenAIRE

坂東, 武彦; 戸田, 春男; 安藤, 誠男; 高木, 峰夫; 吉沢, 豊久; 原, 直人; Bando, Takehiko; Toda, Haruo; Ando, Tomoo; Takagi, Mineo; Yoshizawa, Toyohisa; Hara, Naoto

1993-01-01

Experimental findings obtained by our group were reviewed, and functional significance of the visual association cortex in controlling lens accommodation and ocular convergence was discussed. By intracortical microstimulation in an extrastriate visual area in the cat, lens accommodation and vergence eye movement were evoked. In the same cortical area, a group of neurons was also activated in correlation with lens accommodation or ocular convergence. In addition, after the lesion in this area,...

Effect of third-order aberrations on dynamic accommodation.

Science.gov (United States)

López-Gil, Norberto; Rucker, Frances J; Stark, Lawrence R; Badar, Mustanser; Borgovan, Theodore; Burke, Sean; Kruger, Philip B

2007-03-01

We investigate the potential for the third-order aberrations coma and trefoil to provide a signed cue to accommodation. It is first demonstrated theoretically (with some assumptions) that the point spread function is insensitive to the sign of spherical defocus in the presence of odd-order aberrations. In an experimental investigation, the accommodation response to a sinusoidal change in vergence (1-3D, 0.2Hz) of a monochromatic stimulus was obtained with a dynamic infrared optometer. Measurements were obtained in 10 young visually normal individuals with and without custom contact lenses that induced low and high values of r.m.s. trefoil (0.25, 1.03 microm) and coma (0.34, 0.94 microm). Despite variation between subjects, we did not find any statistically significant increase or decrease in the accommodative gain for low levels of trefoil and coma, although effects approached or reached significance for the high levels of trefoil and coma. Theoretical and experimental results indicate that the presence of Zernike third-order aberrations on the eye does not seem to play a crucial role in the dynamics of the accommodation response.

The utilization of water courses for the production of electric power. Report from a working group

International Nuclear Information System (INIS)

1992-01-01

The problems connected with damming Danish water courses to enable the production of hydroelectricity are discussed. These constraints are generally related to conservation principles and cultural historical interests. It is observed that attempts are usually made to remove dams constructed in water courses such as streams and brooks, in order to ensure the free passage of fish and small animals and it is the opinion of the working group that this policy should continue to be followed. Otherwise alternative methods (such as fish staircases and fish sluices) should be set up to enable the fish to pass through without getting entangled with any turbines. Consideration must be given to the preservation of items of cultural-historical interest. Where waters are stagnant, at least half of the water volume should be left untouched for fish passage, and in other non-stagnant water areas water should be reserved for fish passage. The amount of necessary water volume should be assessed in individual cases. The local authorities have agreed that legislation on dams, the establishment of fauna and fish passages and the dedication of free waters to fish passage should be coordinated. (AB)

Frequency of convergence and accommodative disorders in a clinical population of Mashhad, Iran.

Science.gov (United States)

Hoseini-Yazdi, Seyed Hosein; Yekta, AbbasAli; Nouri, Hosein; Heravian, Javad; Ostadimoghaddam, Hadi; Khabazkhoob, Mehdi

2015-01-01

To investigate the frequency of convergence and accommodation anomalies in an optometric clinical setting in Mashhad, Iran, and to determine tests with highest accuracy in diagnosing these anomalies. From 261 patients who came to the optometric clinics of Mashhad University of Medical Sciences during a month, 83 of them were included in the study based on the inclusion criteria. Near point of convergence (NPC), near and distance heterophoria, monocular and binocular accommodative facility (MAF and BAF, respectively), lag of accommodation, positive and negative fusional vergences (PFV and NFV, respectively), AC/A ratio, relative accommodation, and amplitude of accommodation (AA) were measured to diagnose the convergence and accommodation anomalies. The results were also compared between symptomatic and asymptomatic patients. The accuracy of these tests was explored using sensitivity (S), specificity (Sp), and positive and negative likelihood ratios (LR+, LR-). Mean age of the patients was 21.3 ± 3.5 years and 14.5% of them had specific binocular and accommodative symptoms. Convergence and accommodative anomalies were found in 19.3% of the patients; accommodative excess (4.8%) and convergence insufficiency (3.6%) were the most common accommodative and convergence disorders, respectively. Symptomatic patients showed lower values for BAF (p = .003), MAF (p = .001), as well as AA (p = .001) compared with asymptomatic patients. Moreover, BAF (S = 75%, Sp = 62%) and MAF (S = 62%, Sp = 89%) were the most accurate tests for detecting accommodative and convergence disorders in terms of both sensitivity and specificity. Convergence and accommodative anomalies are the most common binocular disorders in optometric patients. Including tests of monocular and binocular accommodative facility in routine eye examinations as accurate tests to diagnose these anomalies requires further investigation.

Combining turbine blade-strike and life cycle models to assess mitigation strategies for fish passing dams

Energy Technology Data Exchange (ETDEWEB)

Ferguson, J.W. [National Marine Fisheries Service, Seattle, WA (United States). Fish Ecology Div.; Swedish Univ. of Agricultural Sciences, Umea (Sweden). Dept. of Wildlife, Fish and Environmental Studies; Ploskey, G.R. [Battelle-Pacific Northwest National Laboratory, Richland, WA (United States); Zabel, R.W. [National Marine Fisheries Service, Seattle, WA (United States). Fish Ecology Div.; Lundqvist, H. [Swedish Univ. of Agricultural Sciences, Umea (Sweden). Dept. of Wildlife, Fish and Environmental Studies

2008-08-15

Many diadromous and resident fish populations migrate within riverine, freshwater, and marine habitats that have been altered by human activities. This paper developed a tool designed to analyze the effects of dams on fish populations. The model combined a blade-strike model of a hydroelectric turbine and a life cycle model in order to generate point estimates of mortality and incorporate dam passage impacts. The modelling tool was used to study populations of Atlantic salmon and sea trout populations in Sweden which were depressed due to damming, dredging, pollution, and siltation of the rivers. The downstream migrating fish in the rivers passed through a single dam and power station containing Kaplan and Francis turbines. A blade-strike model was developed as the primary mechanism of mortality for the fish. The mortality of juvenile and adult fish and mortality rates from blade-strikes were then entered into salmon life cycle models that incorporated life history variability in age of reproduction and spawning activities. The life cycle model populations in the river were then modelled in hypothetical scenarios. Results of the scenarios were compared with effects from the blade-strike mortality results. Results of the study showed that increases in the number of female salmon escaping above the dam after 20 years was significantly higher when both juveniles and adult fish populations were protected. The model will be used to evaluate strategies designed to conserve fish populations impacted by dams. 49 refs., 9 tabs., 6 figs.

Combining turbine blade-strike and life cycle models to assess mitigation strategies for fish passing dams

International Nuclear Information System (INIS)

Ferguson, J.W.; Zabel, R.W.; Lundqvist, H.

2008-01-01

Many diadromous and resident fish populations migrate within riverine, freshwater, and marine habitats that have been altered by human activities. This paper developed a tool designed to analyze the effects of dams on fish populations. The model combined a blade-strike model of a hydroelectric turbine and a life cycle model in order to generate point estimates of mortality and incorporate dam passage impacts. The modelling tool was used to study populations of Atlantic salmon and sea trout populations in Sweden which were depressed due to damming, dredging, pollution, and siltation of the rivers. The downstream migrating fish in the rivers passed through a single dam and power station containing Kaplan and Francis turbines. A blade-strike model was developed as the primary mechanism of mortality for the fish. The mortality of juvenile and adult fish and mortality rates from blade-strikes were then entered into salmon life cycle models that incorporated life history variability in age of reproduction and spawning activities. The life cycle model populations in the river were then modelled in hypothetical scenarios. Results of the scenarios were compared with effects from the blade-strike mortality results. Results of the study showed that increases in the number of female salmon escaping above the dam after 20 years was significantly higher when both juveniles and adult fish populations were protected. The model will be used to evaluate strategies designed to conserve fish populations impacted by dams. 49 refs., 9 tabs., 6 figs

Longitudinal habitat disruption in Neotropical streams: fish assemblages under the influence of culverts

Directory of Open Access Journals (Sweden)

José Roberto Mariano

Full Text Available This study assessed differences in fish assemblages existing upstream and downstream two types of culverts, one on each of two different Neotropical streams. We analyzed the composition and structure of the ichthyofauna and tested for spatial patterns. Fish sampling was carried out monthly between November 2009 and October 2010 using different fishing gears. We collected 2,220 fish of 33 species; 901 in stretches of the Lopeí stream - circular culvert and 1,310 in stretches of the Pindorama stream - box culvert. Fish abundance was similar in upstream and downstream stretches of the circular culvert, whereas it was slightly higher in the upstream than downstream stretch for the box culvert. Characiformes predominated in the upstream stretch of both culverts. On the other hand, Siluriformes was abundant in the downstream stretch of the circular culvert, with similar abundance in the stretches of the box culvert. Species richness and diversity (Shannon-Weiner Index were higher in the downstream stretch of the circular culvert, but they were similar in both stretches of the box culvert. The most abundant species were Astyanax altiparanae, A. paranae, A. fasciatus, Ancistrus sp., and Hypostomus sp. The last two species were more abundant in the downstream stretch of the circular culvert, and similar in stretches of the box culvert. Our study indicated variations in the species abundance, richness, and diversity between upstream and downstream stretches in particular of the circular culvert in the Lopeí stream, suggesting that fish movements are restrained more intensively in this culvert, especially for Siluriformes. The drop in the circular culvert outlet probably created passage barriers especially for those fish that has no ability to jump, where downstream erosion could lead to culvert perching. Studies on appropriate road crossing design or installation are fundamental whereas improvements in these structures can restore the connectivity of

Disabilities in the workplace: recruitment, accommodation, and retention.

Science.gov (United States)

Davis, Linda

2005-07-01

Who has never had a need for accommodation to perform a job because of age-related changes, gender issues related to family care, religious practices, health status, or disability? Who has never had the benefit of universal accommodations designed to provide access for individuals with disabilities, such as using the handicap button to open a door when one's arms are loaded? All of society has had the benefit of inclusion of individuals with disabilities within the work force. Occupational health nurses are essential to accommodating new employees with disabilities, assisting ill or injured employees in returning to work, and changing attitudes toward disabled workers. Additionally, nurses have the skills and knowledge for leading and managing newly emerging disease management programs for workers with disabilities caused by chronic illness.

Caffeine intake is associated with pupil dilation and enhanced accommodation.

Science.gov (United States)

Abokyi, S; Owusu-Mensah, J; Osei, K A

2017-04-01

PurposeIt is purported that caffeine, an autonomic stimulant, affects visual performance. This study sought to assess whether caffeine intake was associated with changes in pupil size and/or amplitude of accommodation.Patients and methodsA double-masked, crossover study was conducted in 50 healthy subjects of age range 19 to 25 years. Subjects were randomized to treatments such that subjects consumed either 250 mg caffeine drink or vehicle on separate days. Amplitude of accommodation was measured by the push-up technique, and pupil size using a millimeter ruler fixed to a slit lamp biomicroscope in dim illumination (5 lux). Amplitude of accommodation and pupil size were taken at baseline, and at 30, 60 and 90 min time points post treatment. Repeated measures one-way ANOVA and paired t-test were used in analyzing data.ResultsAmplitude of accommodation and pupil size after caffeine intake were significantly greater than vehicle (Pcaffeine beverage was associated with significant increases in amplitude of accommodation and pupil size with time (Pcaffeine. This study suggests caffeine may have some influence on visual functions.

Utility accommodation and conflict tracker (UACT) installation and configuration manual.

Science.gov (United States)

2009-02-01

Project 0-5475 performed a comprehensive analysis of utility conflict data/information flows between utility : accommodation stakeholders in the Texas Department of Transportation project development process, : developed data models to accommodate wo...

Testing the Contingency Theory of Accommodation in Public Relations.

Science.gov (United States)

Cancel, Amanda E.; Mitrook, Michael A.; Cameron, Glen T.

1999-01-01

Interviews 18 public-relations professionals to provide grounding and refinement of the contingency theory of accommodation in public relations. Supports a continuum from pure accommodation to pure advocacy and a matrix of variables affecting the continuum. Concludes that the practitioners' view of their communication world offers validity to the…

Relationship of ocular accommodation and motor skills performance in developmental coordination disorder.

Science.gov (United States)

Rafique, Sara A; Northway, Nadia

2015-08-01

Ocular accommodation provides a well-focussed image, feedback for accurate eye movement control, and cues for depth perception. To accurately perform visually guided motor tasks, integration of ocular motor systems is essential. Children with motor coordination impairment are established to be at higher risk of accommodation anomalies. The aim of the present study was to examine the relationship between ocular accommodation and motor tasks, which are often overlooked, in order to better understand the problems experienced by children with motor coordination impairment. Visual function, gross and fine motor skills were assessed in children with developmental coordination disorder (DCD) and typically developing control children. Children with DCD had significantly poorer accommodation facility and amplitude dynamics compared to controls. Results indicate a relationship between impaired accommodation and motor skills. Specifically, accommodation anomalies correlated with visual motor, upper limb and fine dexterity task performance. Consequently, we argue accommodation anomalies influence the ineffective coordination of action and perception in DCD. Furthermore, reading disabilities were related to poorer motor performance. We postulate the role of the fastigial nucleus as a common pathway for accommodation and motor deficits. Implications of the findings and recommended visual screening protocols are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

An Economic Analysis of Container Shipping Through Canadian Northwest Passage

Directory of Open Access Journals (Sweden)

Dongqin Lu

2014-12-01

This paper considers Canada's sovereignty in matters of navigation over the waters at the Arctic Archipelago, in the form of a toll fee for passage usage. We concluded that the NWP has an advantage over the Panama Canal if it is open for free international passage, regardless of ship size. However, if it is not free, its advantages depend on its toll fee. The lower the toll fee is, the more advantages the NWP will boast.

Fire passage on geomorphic fractures in Cerrado: effect on vegetation

OpenAIRE

Otacílio Antunes Santana; José Marcelo Imaña Encinas; Flávio Luiz de Souza Silveira

2017-01-01

Geomorphic fracture is a natural geologic formation that sometimes forms a deep fissure in the rock with the establishment of soil and vegetation. The objective of this work was to analyze vegetation within geomorphic fractures under the effect of wildfire passage. The biometric variables evaluated before and after fire passage were: diameter, height, leaf area index, timber volume, grass biomass, number of trees and shrubs and of species. Results (in fractures) were compared to adjacent area...

Accommodating Elementary Students' Learning Styles.

Science.gov (United States)

Wallace, James

1995-01-01

Examines the perceptual learning style preferences of sixth- and seventh-grade students in the Philippines. Finds that the visual modality was the most preferred and the auditory modality was the least preferred. Offers suggestions for accommodating visual, tactile, and kinesthetic preferences. (RS)

Accommodation and convergence during sustained computer work.

Science.gov (United States)

Collier, Juanita D; Rosenfield, Mark

2011-07-01

With computer usage becoming almost universal in contemporary society, the reported prevalence of computer vision syndrome (CVS) is extremely high. However, the precise physiological mechanisms underlying CVS remain unclear. Although abnormal accommodation and vergence responses have been cited as being responsible for the symptoms produced, there is little objective evidence to support this claim. Accordingly, this study measured both of these oculomotor parameters during a sustained period of computer use. Subjects (N = 20) were required to read text aloud from a laptop computer at a viewing distance of 50 cm for a sustained 30-minute period through their habitual refractive correction. At 2-minute intervals, the accommodative response (AR) to the computer screen was measured objectively using a Grand Seiko WAM 5500 optometer (Grand Seiko, Hiroshima, Japan). Additionally, the vergence response was assessed by measuring the associated phoria (AP), i.e., prism to eliminate fixation disparity, using a customized fixation disparity target that appeared on the computer screen. Subjects were asked to rate the degree of difficulty of the reading task on a scale from 1 to 10. Mean accommodation and AP values during the task were 1.07 diopters and 0.74∆ base-in (BI), respectively. The mean discomfort score was 4.9. No significant changes in accommodation or vergence were observed during the course of the 30-minute test period. There was no significant difference in the AR as a function of subjective difficulty. However, the mean AP for the subjects who reported the least and greatest discomfort during the task was 1.55∆ BI and 0, respectively (P = 0.02). CVS, after 30 minutes was worse in subjects exhibiting zero fixation disparity when compared with those subjects having a BI AP but does not appear to be related to differences in accommodation. A slightly reduced vergence response increases subject comfort during the task. Copyright © 2011 American Optometric

[Effects of visual optical stimuli for accommodation-convergence system on asthenopia].

Science.gov (United States)

Iwasaki, Tsuneto; Tawara, Akihiko; Miyake, Nobuyuki

2006-01-01

We investigated the effect on eyestrain of optical stimuli that we designed for accommodation and convergence systems. Eight female students were given optical stimuli for accommodation and convergence systems for 1.5 min immediately after 20 min of a sustained task on a 3-D display. Before and after the trial, their ocular functions were measured and their symptoms were assessed. The optical stimuli were applied by moving targets of scenery images far and near around the far point position of both eyes on a horizonal place, which induced divergence in the direction of the eye position of rest. In a control group, subjects rested with closed eyes for 1.5 min instead of applying the optical stimuli. There were significant changes in the accommodative contraction time (from far to near) and the accommodative relaxation time (from near to far) and the lag of accommodation at near target, from 1.26 s to 1.62 s and from 1.49 s to 1.63 s and from 0.5 D to 0.65 D, respectively, and in the symptoms in the control group after the duration of closed-eye rest. In the stimulus group, however, the changes of those functions were smaller than in the control group. From these results, we suggest that our designed optical stimuli for accommodation and convergence systems are effective on asthenopia following accommodative dysfunction.

Detection of the spatiotemporal trends of mercury in Lake Erie fish communities: a Bayesian approach.

Science.gov (United States)

Azim, M Ekram; Kumarappah, Ananthavalli; Bhavsar, Satyendra P; Backus, Sean M; Arhonditsis, George

2011-03-15

The temporal trends of total mercury (THg) in four fish species in Lake Erie were evaluated based on 35 years of fish contaminant data. Our Bayesian statistical approach consists of three steps aiming to address different questions. First, we used the exponential and mixed-order decay models to assess the declining rates in four intensively sampled fish species, i.e., walleye (Stizostedion vitreum), yellow perch (Perca flavescens), smallmouth bass (Micropterus dolomieui), and white bass (Morone chrysops). Because the two models postulate monotonic decrease of the THg levels, we included first- and second-order random walk terms in our statistical formulations to accommodate nonmonotonic patterns in the data time series. Our analysis identified a recent increase in the THg concentrations, particularly after the mid-1990s. In the second step, we used double exponential models to quantify the relative magnitude of the THg trends depending on the type of data used (skinless-boneless fillet versus whole fish data) and the fish species examined. The observed THg concentrations were significantly higher in skinless boneless fillet than in whole fish portions, while the whole fish portions of walleye exhibited faster decline rates and slower rates of increase relative to the skinless boneless fillet data. Our analysis also shows lower decline rates and higher rates of increase in walleye relative to the other three fish species examined. The food web structural shifts induced by the invasive species (dreissenid mussels and round goby) may be associated with the recent THg trends in Lake Erie fish.

Magnifications of Single and Dual Element Accommodative Intraocular Lenses: Paraxial Optics Analysis

Science.gov (United States)

Ale, Jit B; Manns, Fabrice; Ho, Arthur

2010-01-01

Purpose Using an analytical approach of paraxial optics, we evaluated the magnification of a model eye implanted with single-element (1E) and dual-element (2E) translating-optics accommodative intraocular lenses (AIOL) with an objective of understanding key control parameters relevant to their design. Potential clinical implications of the results arising from pseudophakic accommodation were also considered. Methods Lateral and angular magnifications in a pseudophakic model eye were analyzed using the matrix method of paraxial optics. The effects of key control parameters such as direction (forward or backward) and distance (0 to 2 mm) of translation, power combinations of the 2E-AIOL elements (front element power range +20.0 D to +40.0 D), and amplitudes of accommodation (0 to 4 D) were tested. Relative magnification, defined as the ratio of the retinal image size of the accommodated eye to that of unaccommodated phakic (rLM1) or pseudophakic (rLM2) model eyes, was computed to determine how retinal image size changes with pseudophakic accommodation. Results Both lateral and angular magnifications increased with increased power of the front element in 2E-AIOL and amplitude of accommodation. For a 2E-AIOL with front element power of +35 D, rLM1 and rLM2 increased by 17.0% and 16.3%, respectively, per millimetre of forward translation of the element, compared to the magnification at distance focus (unaccommodated). These changes correspond to a change of 9.4% and 6.5% per dioptre of accommodation, respectively. Angular magnification also increased with pseudophakic accommodation. 1E-AIOLs produced consistently less magnification than 2E-AIOLs. Relative retinal image size decreased at a rate of 0.25% with each dioptre of accommodation in the phakic model eye. The position of the image space nodal point shifted away from the retina (towards the cornea) with both phakic and pseudophakic accommodation. Conclusion Power of the mobile element, and amount and direction of

Statistical Analysis of the First Passage Path Ensemble of Jump Processes

Science.gov (United States)

von Kleist, Max; Schütte, Christof; Zhang, Wei

2018-02-01

The transition mechanism of jump processes between two different subsets in state space reveals important dynamical information of the processes and therefore has attracted considerable attention in the past years. In this paper, we study the first passage path ensemble of both discrete-time and continuous-time jump processes on a finite state space. The main approach is to divide each first passage path into nonreactive and reactive segments and to study them separately. The analysis can be applied to jump processes which are non-ergodic, as well as continuous-time jump processes where the waiting time distributions are non-exponential. In the particular case that the jump processes are both Markovian and ergodic, our analysis elucidates the relations between the study of the first passage paths and the study of the transition paths in transition path theory. We provide algorithms to numerically compute statistics of the first passage path ensemble. The computational complexity of these algorithms scales with the complexity of solving a linear system, for which efficient methods are available. Several examples demonstrate the wide applicability of the derived results across research areas.

Partner Accommodation Moderates Treatment Outcomes for Couple Therapy for Posttraumatic Stress Disorder

Science.gov (United States)

Fredman, Steffany J.; Pukay-Martin, Nicole D.; Macdonald, Alexandra; Wagner, Anne C.; Vorstenbosch, Valerie; Monson, Candice M.

2015-01-01

Objective Partner accommodation of posttraumatic stress disorder (PTSD) symptoms (i.e., altering one’s own behaviors to minimize patient distress and/or relationship conflict due to patients’ PTSD symptoms) has been shown to be positively associated with patient and partner psychopathology and negatively associated with patient and partner relationship satisfaction cross-sectionally. However, the prognostic value of partner accommodation in treatment outcomes is unknown. The goals of the present study were to determine if partner accommodation decreases as a function of couple therapy for PTSD and if pretreatment partner accommodation moderates the efficacy of couple therapy for PTSD. Method Thirty-nine patients with PTSD and their intimate partners (n = 39) were enrolled in a randomized controlled trial of cognitive-behavioral conjoint therapy (CBCT) for PTSD (Monson & Fredman, 2012) and received CBCT for PTSD immediately or after three months of waiting. Blinded assessors determined clinician-rated PTSD symptoms and patient-rated PTSD and depressive symptoms and relationship satisfaction at baseline, mid-treatment/4 weeks of waiting, and posttreatment/12 weeks of waiting. Results Contrary to expectation, partner accommodation levels did not change over time for either treatment condition. However, baseline partner accommodation significantly moderated treatment outcomes. Higher levels of partner accommodation were associated with greater improvements in PTSD, depressive symptoms, and relationship satisfaction among patients receiving CBCT for PTSD compared with waiting list. At lower levels of partner accommodation, patients in both groups improved or remained at low levels of these outcomes. Conclusions Individuals with PTSD who have more accommodating partners may be particularly well-suited for couple therapy for PTSD. PMID:26501498

Spasm of accommodation associated with closed head trauma.

Science.gov (United States)

Chan, R V Paul; Trobe, Jonathan D

2002-03-01

Spasm of accommodation, creating pseudomyopia, is generally associated with miosis and excess convergence as part of spasm of the near reflex. It may also exist as an isolated entity, usually attributed to psychogenic causes. We present six cases of accommodative spasm associated with closed head injury. All patients were male, ranging in age between 16 and 37 years. The degree of pseudomyopia, defined as the difference between manifest and cycloplegic refraction, was 1.5 to 2 diopters. A 3-year trial of pharmacologically induced cycloplegia in one patient did not lead to reversal of the spasm when the cycloplegia was stopped. All patients required the manifest refraction to see clearly at distance. The pseudomyopia endured for at least 7 years following head trauma. This phenomenon may represent traumatic activation or disinhibition of putative brain stem accommodation centers in young individuals.

"The Caterpillar": A Novel Reading Passage for Assessment of Motor Speech Disorders

Science.gov (United States)

Patel, Rupal; Connaghan, Kathryn; Franco, Diana; Edsall, Erika; Forgit, Dory; Olsen, Laura; Ramage, Lianna; Tyler, Emily; Russell, Scott

2013-01-01

Purpose: A review of the salient characteristics of motor speech disorders and common assessment protocols revealed the need for a novel reading passage tailored specifically to differentiate between and among the dysarthrias (DYSs) and apraxia of speech (AOS). Method: "The Caterpillar" passage was designed to provide a contemporary, easily read,…

Neutron Imaging for Selective Laser Melting Inconel Hardware with Internal Passages

Science.gov (United States)

Tramel, Terri L.; Norwood, Joseph K.; Bilheux, Hassina

2014-01-01

Additive Manufacturing is showing great promise for the development of new innovative designs and large potential life cycle cost reduction for the Aerospace Industry. However, more development work is required to move this technology into space flight hardware production. With selective laser melting (SLM), hardware that once consisted of multiple, carefully machined and inspected pieces, joined together can be made in one part. However standard inspection techniques cannot be used to verify that the internal passages are within dimensional tolerances or surface finish requirements. NASA/MSFC traveled to Oak Ridge National Lab's (ORNL) Spallation Neutron Source to perform some non-destructive, proof of concept imaging measurements to assess the capabilities to understand internal dimensional tolerances and internal passages surface roughness. This presentation will describe 1) the goals of this proof of concept testing, 2) the lessons learned when designing and building these Inconel 718 test specimens to minimize beam time, 3) the neutron imaging test setup and test procedure to get the images, 4) the initial results in images, volume and a video, 4) the assessment of using this imaging technique to gather real data for designing internal flow passages in SLM manufacturing aerospace hardware, and lastly 5) how proper cleaning of the internal passages is critically important. In summary, the initial results are very promising and continued development of a technique to assist in SLM development for aerospace components is desired by both NASA and ORNL. A plan forward that benefits both ORNL and NASA will also be presented, based on the promising initial results. The initial images and volume reconstruction showed that clean, clear images of the internal passages geometry are obtainable. These clear images of the internal passages of simple geometries will be compared to the build model to determine any differences. One surprising result was that a new cleaning

ICT Adoption and Development: Issues in Rural Accommodation

OpenAIRE

Reino, Sofia; Frew, Andrew J; Albacete-Saez, Carlos

2010-01-01

Purpose – The work described in this paper is of direct relevance to those with an interest in the phenomena surrounding ICT (Information and Communication Technologies) adoption by the rural accommodation sector. The paper provides the results from a preliminary study, which examined differences in the level of inter-firm technology adoption between rural and urban accommodation establishments within a major tourism destination, Scotland. Design/methodology/approach – A survey was conducted,...

Accommodating World Englishes in Developing EFL Learners' Oral Communication

Science.gov (United States)

Mukminatien, Nur

2012-01-01

This article aims to discuss issues of World Englishes (WEs) and the implications in ELT. It explores the extent to which WEs are taken into account as emerging English varieties different from inner circle varieties, how WEs should be accommodated by English teachers, and which standard to adopt to accommodate learner's linguistic needs for…

Convergence and accommodation development is pre-programmed in premature infants

Science.gov (United States)

Horwood, Anna M; Toor, Sonia S; Riddell, Patricia M

2015-01-01

Purpose This study investigated whether vergence and accommodation development in pre-term infants is pre-programmed or is driven by experience. Methods 32 healthy infants, born at mean 34 weeks gestation (range 31.2-36 weeks) were compared with 45 healthy full-term infants (mean 40.0 weeks) over a 6 month period, starting at 4-6 weeks post-natally. Simultaneous accommodation and convergence to a detailed target were measured using a Plusoptix PowerRefII infra-red photorefractor as a target moved between 0.33m and 2m. Stimulus/response gains and responses at 0.33m and 2m were compared by both corrected (gestational) age and chronological (post-natal) age. Results When compared by their corrected age, pre-term and full-term infants showed few significant differences in vergence and accommodation responses after 6-7 weeks of age. However, when compared by chronological age, pre-term infants’ responses were more variable, with significantly reduced vergence gains, reduced vergence response at 0.33m, reduced accommodation gain, and increased accommodation at 2m, compared to full-term infants between 8-13 weeks after birth. Conclusions When matched by corrected age, vergence and accommodation in pre-term infants show few differences from full-term infants’ responses. Maturation appears pre-programmed and is not advanced by visual experience. Longer periods of immature visual responses might leave pre-term infants more at risk of development of oculomotor deficits such as strabismus. PMID:26275135

Time Perspective and Emotion Regulation as Predictors of Age-Related Subjective Passage of Time.

Science.gov (United States)

Wittmann, Marc; Rudolph, Tina; Linares Gutierrez, Damisela; Winkler, Isabell

2015-12-17

Hardly any empirical work exists concerning the relationship between the intra-individually stable time perspective relating to the past, present, and future and the subjective speed of time passing in everyday life. Moreover, studies consistently show that the subjective passage of time over the period of the last ten years speeds up as we get older. Modulating variables influencing this phenomenon are still unknown. To investigate these two unresolved issues, we conducted an online survey with n = 423 participants ranging in age between 17 and 81 assessing trait time perspective of the past, present, and future, and relating these subscales with a battery of measures pertaining to the subjective passage of time. Moreover, the subjective passage of time as an age-dependent variable was probed in relationship to emotion awareness, appraisal and regulation. Results show how present hedonism is linked with having fewer routines in life and a faster passage of the last week; the past negative perspective is related to time pressure, time expansion and more routine; a pronounced future perspective is related to a general faster passage of time. Importantly, increased emotion regulation and a balanced time perspective are related to a slower passage of the last ten years. These novel findings are discussed within models of time perception and the time perspective.

Fish allergy and fish allergens

DEFF Research Database (Denmark)

Kuehn, A; Hilger, Christiane; Ollert, Markus

2016-01-01

Fish is one of the main elicitors for food allergies. For a long time, the clinical picture of fish allergy was reduced to the following features. First, fish-allergic patients suffer from a high IgE cross-reactivity among fishes so that they have to avoid all species. Second, clinically relevant...... symptoms are linked to the presence of IgE-antibodies recognizing parvalbumin, the fish panallergen. This view was challenged by results from recent studies as follows. 1. Allergic reactions which are limited to single or several fish species (mono-or oligosensitisations) apply not only to single cases...... but patients with this phenotype constitute an important sub-group among fish-allergic individuals. 2. Newly identified fish allergens, enolases, aldolases, and fish gelatin, are of high relevance as the majority of the fish-allergic individuals seem to develop specific IgE against these proteins. The present...

Accommodating ‘design’

DEFF Research Database (Denmark)

Karpova, Yulia

2013-01-01

This article investigates the background of Soviet industrial design in Soviet art theory. Instead of considering design's interconnection with technology and science, or with consumption and everyday life, the author traces its conceptualisation as a new artistic phenomenon. Using archival records...... of professional discussions, polemical articles in the art press and design projects, the author looks at how industrial design was incorporated into the Soviet order of things. She concludes that accommodation of the Western model was the way to reform the system of socialism from inside, typical for the Soviet...

EDRP public local inquiry, UKAEA/BNFL precognition on: Contractor accommodation

International Nuclear Information System (INIS)

Scott, W.

1986-01-01

The availability of accommodation for contractors working on the proposed EDRP at Dounreay is discussed. It is predicted that the contractors could be accommodated without the need for special arrangement and with no adverse effect on the tourist industry. (U.K.)

Demersal fish assemblages on seamounts and other rugged features in the northeastern Caribbean

Science.gov (United States)

Quattrini, Andrea M.; Demopoulos, Amanda W. J.; Singer, Randal; Roa-Varon, Adela; Chaytor, Jason D.

2017-05-01

Recent investigations of demersal fish communities in deepwater (>50 m) habitats have considerably increased our knowledge of the factors that influence the assemblage structure of fishes across mesophotic to deep-sea depths. While different habitat types influence deepwater fish distribution, whether different types of rugged seafloor features provide functionally equivalent habitat for fishes is poorly understood. In the northeastern Caribbean, different types of rugged features (e.g., seamounts, banks, canyons) punctuate insular margins, and thus create a remarkable setting in which to compare demersal fish communities across various features. Concurrently, several water masses are vertically layered in the water column, creating strong stratification layers corresponding to specific abiotic conditions. In this study, we examined differences among fish assemblages across different features (e.g., seamount, canyon, bank/ridge) and water masses at depths ranging from 98 to 4060 m in the northeastern Caribbean. We conducted 26 remotely operated vehicle dives across 18 sites, identifying 156 species of which 42% of had not been previously recorded from particular depths or localities in the region. While rarefaction curves indicated fewer species at seamounts than at other features in the NE Caribbean, assemblage structure was similar among the different types of features. Thus, similar to seamount studies in other regions, seamounts in the Anegada Passage do not harbor distinct communities from other types of rugged features. Species assemblages, however, differed among depths, with zonation generally corresponding to water mass boundaries in the region. High species turnover occurred at depths <1200 m, and may be driven by changes in water mass characteristics including temperature (4.8-24.4 °C) and dissolved oxygen (2.2-9.5 mg per l). Our study suggests the importance of water masses in influencing community structure of benthic fauna, while considerably adding

Workplace Accommodation for Persons With IBD: What Is Needed and What Is Accessed.

Science.gov (United States)

Chhibba, Tarun; Walker, John R; Sexton, Kathryn; Restall, Gayle; Ivekovic, Melony; Shafer, Leigh Ann; Singh, Harminder; Targownik, Laura E; Bernstein, Charles N

2017-10-01

People with inflammatory bowel disease (IBD) often experience periods of illness that interfere with their ability to work. We aimed to understand the need for workplace accommodation during periods of acute illness among persons IBD. Participants were recruited from the population-based University of Manitoba Research Registry and received a survey including questions assessing experiences with workplace accommodations. Data were analyzed using descriptive statistics and multivariate logistic regression modelling. A total of 1143 individuals responded to the survey (46% response rate), of whom 881 had experienced IBD symptoms in the workplace and were included in the analysis. The mean age was 48.3 years (standard deviation, 10.9); 61% were female. Mean IBD duration was 20.6 years (standard deviation, 10.5). Most respondents (73%) described IBD symptoms experienced in the workplace as severe to very severe. The most commonly required accommodations were time to go to medical appointments during working hours (81%), easy access to a toilet (71%), and a chance to take a break when not feeling well (54%). Most accommodations were arranged informally or through a supervisor. The accommodations required were very or somewhat easy to arrange about half the time. Being female, having high symptom severity, and high level of current distress were associated with a need for more accommodations, difficulty implementing accommodations, and not asking for needed accommodations. This study provides important information as to the types of accommodations that are necessary, common practices arranging for these, and level of difficulty arranging accommodations. Furthermore, characteristics associated with greater need for accommodation, reluctance to ask for them, and difficulty in arranging them were identified. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Spin-Label CW Microwave Power Saturation and Rapid Passage with Triangular Non-Adiabatic Rapid Sweep (NARS) and Adiabatic Rapid Passage (ARP) EPR Spectroscopy

Science.gov (United States)

Kittell, Aaron W.; Hyde, James S.

2015-01-01

Non-adiabatic rapid passage (NARS) electron paramagnetic resonance (EPR) spectroscopy was introduced by Kittell, A.W., Camenisch, T.G., Ratke, J.J. Sidabras, J.W., Hyde, J.S., 2011 as a general purpose technique to collect the pure absorption response. The technique has been used to improve sensitivity relative to sinusoidal magnetic field modulation, increase the range of inter-spin distances that can be measured under near physiological conditions, and enhance spectral resolution in copper (II) spectra. In the present work, the method is extended to CW microwave power saturation of spin-labeled T4 Lysozyme (T4L). As in the cited papers, rapid triangular sweep of the polarizing magnetic field was superimposed on slow sweep across the spectrum. Adiabatic rapid passage (ARP) effects were encountered in samples undergoing very slow rotational diffusion as the triangular magnetic field sweep rate was increased. The paper reports results of variation of experimental parameters at the interface of adiabatic and non-adiabatic rapid sweep conditions. Comparison of the forward (up) and reverse (down) triangular sweeps is shown to be a good indicator of the presence of rapid passage effects. Spectral turning points can be distinguished from spectral regions between turning points in two ways: differential microwave power saturation and differential passage effects. Oxygen accessibility data are shown under NARS conditions that appear similar to conventional field modulation data. However, the sensitivity is much higher, permitting, in principle, experiments at substantially lower protein concentrations. Spectral displays were obtained that appear sensitive to rotational diffusion in the range of rotational correlation times of 10−3 to 10−7 s in a manner that is analogous to saturation transfer spectroscopy. PMID:25917132

Efforts to reduce mortality to hydroelectric turbine-passed fish: locating and quantifying damaging shear stresses.

Science.gov (United States)

Cada, Glenn; Loar, James; Garrison, Laura; Fisher, Richard; Neitzel, Duane

2006-06-01

Severe fluid forces are believed to be a source of injury and mortality to fish that pass through hydroelectric turbines. A process is described by which laboratory bioassays, computational fluid dynamics models, and field studies can be integrated to evaluate the significance of fluid shear stresses that occur in a turbine. Areas containing potentially lethal shear stresses were identified near the stay vanes and wicket gates, runner, and in the draft tube of a large Kaplan turbine. However, under typical operating conditions, computational models estimated that these dangerous areas comprise less than 2% of the flow path through the modeled turbine. The predicted volumes of the damaging shear stress zones did not correlate well with observed fish mortality at a field installation of this turbine, which ranged from less than 1% to nearly 12%. Possible reasons for the poor correlation are discussed. Computational modeling is necessary to develop an understanding of the role of particular fish injury mechanisms, to compare their effects with those of other sources of injury, and to minimize the trial and error previously needed to mitigate those effects. The process we describe is being used to modify the design of hydroelectric turbines to improve fish passage survival.

Is There a Downside of Job Accommodations? An Employee Perspective on Individual Change Processes

Science.gov (United States)

Kensbock, Julia M.; Boehm, Stephan A.; Bourovoi, Kirill

2017-01-01

By modifying the work environments, work routines, and work tasks of employees with health restrictions, organizations can effectively help them continue to perform their jobs successfully. As such, job accommodations are an effective tool to secure the continued employment of aging workers who develop disabilities across their life span. However, while accommodations tackle health-related performance problems, they might create new challenges on the part of the affected employee. Building on the organizational change and accommodations literatures, we propose a theoretical framework of negative experiences during accommodation processes and apply it to qualitative data from group interviews with 73 manufacturing workers at a German industrial company who were part of the company's job accommodation program. Although problems associated with health-related impairments were mostly solved by accommodation, affected employees with disabilities reported about interpersonal problems and conflicts similar to those that typically occur during organizational change. Lack of social support as well as poor communication and information were raised as criticisms. Furthermore, our findings indicate that discrimination, bullying, and maltreatment appear to be common during accommodation processes. To make accommodation processes more successful, we derive recommendations from the organizational change literature and apply it to the accommodation context. We also emphasize unique characteristics of the accommodation setting and translate these into practical implications. PMID:28979218

Entropy Minimization Design Approach of Supersonic Internal Passages

Directory of Open Access Journals (Sweden)

Jorge Sousa

2015-08-01

Full Text Available Fluid machinery operating in the supersonic regime unveil avenues towards more compact technology. However, internal supersonic flows are associated with high aerodynamic and thermal penalties, which usually prevent their practical implementation. Indeed, both shock losses and the limited operational range represent particular challenges to aerodynamic designers that should be taken into account at the initial phase of the design process. This paper presents a design methodology for supersonic passages based on direct evaluations of the velocity field using the method of characteristics and computation of entropy generation across shock waves. This meshless function evaluation tool is then coupled to an optimization scheme, based on evolutionary algorithms that minimize the entropy generation across the supersonic passage. Finally, we assessed the results with 3D Reynolds Averaged Navier Stokes calculations.

Passages of high energy hadrons through atomic nuclei

International Nuclear Information System (INIS)

Strugalska-Gola, E.; Strugalski, Z.

2001-01-01

The subject matter in this paper are descriptions of more important results of investigations of the intranuclear matter properties by means of hadronic probes (pionic, e.g.). The projectile-nucleus collisions occurred in liquid xenon in the 180 litre xenon bubble chamber. The chamber in the experiments was practically a total 4π angle aperture for detection of the secondary products from the hadron-nucleus collision reactions. All the π +-0 mesons were practically registered with an efficiency near to 100 %. The hadron passages through nuclei (through layers of intranuclear matter) in their pure sort, when multiparticle creation does not occur, were observed. Conclusive information, obtained on the hadron passages, is presented here. It may be used for new nuclear power technology, in radioactive waste neutralization, in other works on intranuclear matter properties

Establishment of an attenuated strain of porcine parvovirus by serial passage at low temperature.

Science.gov (United States)

Fujisaki, Y; Murakami, Y; Suzuki, H

1982-01-01

To prepare a live virus vaccine strain for the prevention of porcine parvovirus infection, the 90HS strain, isolated from the brain of a stillborn porcine fetus, was subjected to the first 45 serial passages in swine kidney established (ESK) cells of porcine kidney origin at 30-35 degrees C and to the 46th and later serial passages in the same cells as these at 32 degrees C. When swine were inoculated with the strain at the 38th passage level possessing such properties as expressed with rct/37+ and rct/40-, they presented viremia, virus discharge, and the transmission of virus to other swine. When swine were inoculated with the strain at the 54th and 55th passage level possessing such properties as expressed with rct/37- and rct/40-, they failed to exhibit viremia, virus discharge, and the transmission of virus to other swine, but retained for a long time hemagglutination-inhibiting antibody which had been produced after inoculation. A low virulent variant strain was obtained after 54 serial passages at low temperature. It was called the HT- strain.

Equivalent refractive index of the human lens upon accommodative response

NARCIS (Netherlands)

Hermans, E.A.; Dubbelman, M.; van der Heijde, R.G.L.; Heethaar, R.M.

2008-01-01

PURPOSE.: To experimentally verify the suggestion of Gullstrand (1909), i.e., that the equivalent refractive index of the human lens increases with accommodation. METHODS.: The left eye of five subjects was focused on different accommodation stimuli, while the right eye was imaged with Scheimpflug

Time Perspective and Emotion Regulation as Predictors of Age-Related Subjective Passage of Time

Science.gov (United States)

Wittmann, Marc; Rudolph, Tina; Linares Gutierrez, Damisela; Winkler, Isabell

2015-01-01

Hardly any empirical work exists concerning the relationship between the intra-individually stable time perspective relating to the past, present, and future and the subjective speed of time passing in everyday life. Moreover, studies consistently show that the subjective passage of time over the period of the last ten years speeds up as we get older. Modulating variables influencing this phenomenon are still unknown. To investigate these two unresolved issues, we conducted an online survey with n = 423 participants ranging in age between 17 and 81 assessing trait time perspective of the past, present, and future, and relating these subscales with a battery of measures pertaining to the subjective passage of time. Moreover, the subjective passage of time as an age-dependent variable was probed in relationship to emotion awareness, appraisal and regulation. Results show how present hedonism is linked with having fewer routines in life and a faster passage of the last week; the past negative perspective is related to time pressure, time expansion and more routine; a pronounced future perspective is related to a general faster passage of time. Importantly, increased emotion regulation and a balanced time perspective are related to a slower passage of the last ten years. These novel findings are discussed within models of time perception and the time perspective. PMID:26694439

Time Perspective and Emotion Regulation as Predictors of Age-Related Subjective Passage of Time

Directory of Open Access Journals (Sweden)

Marc Wittmann

2015-12-01

Full Text Available Hardly any empirical work exists concerning the relationship between the intra-individually stable time perspective relating to the past, present, and future and the subjective speed of time passing in everyday life. Moreover, studies consistently show that the subjective passage of time over the period of the last ten years speeds up as we get older. Modulating variables influencing this phenomenon are still unknown. To investigate these two unresolved issues, we conducted an online survey with n = 423 participants ranging in age between 17 and 81 assessing trait time perspective of the past, present, and future, and relating these subscales with a battery of measures pertaining to the subjective passage of time. Moreover, the subjective passage of time as an age-dependent variable was probed in relationship to emotion awareness, appraisal and regulation. Results show how present hedonism is linked with having fewer routines in life and a faster passage of the last week; the past negative perspective is related to time pressure, time expansion and more routine; a pronounced future perspective is related to a general faster passage of time. Importantly, increased emotion regulation and a balanced time perspective are related to a slower passage of the last ten years. These novel findings are discussed within models of time perception and the time perspective.

Effects of Accommodation, Vergence and Pupil Diameter on Size Estimation When Viewing Displays

National Research Council Canada - National Science Library

Charman, W

1995-01-01

... subtense but lying at different distances, allied to errors in accommodation. Thus an error in accommodation, caused perhaps by the tendency of the accommodation system to revert to its somewhat myopic tonic or resting state (Toates, 1972...

Numerical study of effects of accommodation coefficients on slip phenomena

Energy Technology Data Exchange (ETDEWEB)

Choi, Young Jae; Kwon, Oh Joon [KAIST, Daejeon (Korea, Republic of)

2015-05-15

An unstructured mesh Navier-Stokes solver employing a Maxwell slip boundary condition was developed. The present flow solver was applied to the simulation of flows around an axisymmetric hollow cylinder in a Mach 10.4 free stream, known as Calspan-UB Research Center (CUBRC) Run 14 case, and the velocity slip and the temperature jump on the cylinder surface were investigated. The effect of tangential momentum and thermal accommodation coefficients used in the Maxwell condition was also investigated by adjusting their values. The results show that the reverse flow region is developed on the body surface due to the interaction between the shock and the boundary layer. Also, the shock impingement makes pressure high. The flow properties on the surface agree well with the experimental data, and the velocity slip and the temperature jump vary consistently with the local Knudsen number change. The accommodation coefficients affect the slip phenomena and the size of the flow region. The slip phenomena become larger when both tangential momentum and thermal accommodation coefficients are decreased. However, the range of the reverse flow region decreases when the momentum accommodation coefficient is decreased. The characteristics of the momentum and thermal accommodation coefficients also are overlapped when they are altered together.

A survey of anthropometry and physical accommodation in ergonomics curricula.

Science.gov (United States)

Garneau, Christopher J; Parkinson, Matthew B

2016-01-01

The size and shape of users are an important consideration for many products and environments. Designers and engineers in many disciplines must often accommodate these attributes to meet objectives such as fit and safety. When practitioners have academic training in addressing these issues, it is typically through courses in Human Factors/Ergonomics (HF/E). This paper investigates education related to physical accommodation and offers suggestions for improvement. A survey was conducted wherein 21 instructors at 18 universities in the United States provided syllabi for 29 courses, which were analysed to determine topics related to anthropometry and resources used for the courses. The results show that within the U.S., anthropometry is covered in the majority of courses discussing physical ergonomics, but important related concepts were often omitted (e.g., digital human modelling, multivariate accommodation and variability across global populations). Curricula could be improved by incorporating more accurate anthropometry, multivariate problems and interactive online tools. This paper describes a study investigating collegiate ergonomics courses within the U.S. in the area of physical accommodation. Course schedules and texts were studied for their treatment of several topics related to accommodating the spatial requirements (anthropometry) of users. Recommendations are made for improving course curricula.

Tamsulosin and spontaneous passage of ureteral stones in children: a multi-institutional cohort study.

Science.gov (United States)

Tasian, Gregory E; Cost, Nicholas G; Granberg, Candace F; Pulido, Jose E; Rivera, Marcelino; Schwen, Zeyad; Schulte, Marion; Fox, Janelle A

2014-08-01

Tamsulosin is associated with increased passage of ureteral stones in adults but its effectiveness in children is uncertain. We determined the association between tamsulosin and the spontaneous passage of ureteral stones in children. We performed a multi-institutional retrospective cohort study of patients 18 years or younger who presented between 2007 and 2012 with ureteral stones up to 10 mm and who were treated with tamsulosin or oral analgesics alone. The outcome was spontaneous stone passage, defined as radiographic clearance and/or patient report of passage. Subjects prescribed tamsulosin were matched with subjects prescribed analgesics alone, using nearest neighbor propensity score matching to adjust for treatment selection. Conditional logistic regression models were used to estimate the association between tamsulosin and spontaneous passage of ureteral stones, adjusting for stone size and location. Of 449 children with ureteral stones 334 were eligible for inclusion, and complete data were available for 274 patients from 4 institutions (99 receiving tamsulosin, 175 receiving analgesics alone). Following case matching, there were no differences in age, gender, weight, height, stone size or stone location between the 99 subjects prescribed tamsulosin and the 99 propensity score matched subjects prescribed analgesics alone. In the tamsulosin cohort 55% of ureteral stones passed, compared to 44% in the analgesics alone cohort (p=0.03). In multivariate analysis adjusting for stone size and location tamsulosin was associated with spontaneous passage of ureteral stones (OR 3.31, 95% CI 1.49-7.34). The odds of spontaneous passage of ureteral stones were greater in children prescribed tamsulosin vs analgesics alone. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.