WorldWideScience

Sample records for provincetown harbor swim

  1. [Pearl Harbor.

    Science.gov (United States)

    Johnson, Jennifer, Ed.

    1992-01-01

    This issue of "Loblolly Magazine" was written in observance of the 50th anniversary of the U.S. entrance into World War II. The publication features interviews conducted by East Texas high school students with Clarence Otterman, one of the few survivors of the crew of the USS Arizona, which was bombed during the attack on Pearl Harbor,…

  2. PROPERTIES OF SWIMMING WATER

    Directory of Open Access Journals (Sweden)

    Tayfun KIR

    2004-10-01

    Full Text Available Swimming waters may be hazardous on human health. So, The physicians who work in the facilities, which include swimming areas, are responsible to prevent risks. To ensure hygiene of swimming water, European Swimming Water Directive offers microbiological, physical, and chemical criteria. [TAF Prev Med Bull 2004; 3(5.000: 103-104

  3. Swimming pool cleaner poisoning

    Science.gov (United States)

    Swimming pool cleaner poisoning occurs when someone swallows this type of cleaner, touches it, or breathes in ... The harmful substances in swimming pool cleaner are: Bromine ... copper Chlorine Soda ash Sodium bicarbonate Various mild acids

  4. Swimming pool granuloma

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001357.htm Swimming pool granuloma To use the sharing features on this page, please enable JavaScript. A swimming pool granuloma is a long-term (chronic) skin ...

  5. Laryngoscopy during swimming

    DEFF Research Database (Denmark)

    Walsted, Emil S; Swanton, Laura L; van van Someren, Ken

    2017-01-01

    that precipitates their symptoms. This report provides the first description of the feasibility of performing continuous laryngoscopy during exercise in a swimming environment. The report describes the methodology and safety of the use of continuous laryngoscopy while swimming. Laryngoscope, 2017....

  6. Diarrhea and Swimming

    Science.gov (United States)

    ... 888) 232-6348 Contact CDC–INFO Healthy Swimming Health Benefits of Water-based Exercise Swimmer Protection Steps of ... Disinfection Microbial Testing & Disinfection Swimming Pool Chemicals Injuries & Outdoor Health International Recreational Water RWIs, Swimmer Hygiene, & Behavioral ...

  7. Coastal Harbors Modeling Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Coastal Harbors Modeling Facility is used to aid in the planning of harbor development and in the design and layout of breakwaters, absorbers, etc.. The goal is...

  8. Swimming-pool piles

    International Nuclear Information System (INIS)

    Trioulaire, M.

    1959-01-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10 13 . This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [fr

  9. Swimming Pool Safety

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Safety & Prevention Immunizations All Around At Home At Play ... Español Text Size Email Print Share Swimming Pool Safety Page Content ​What is the best way to ...

  10. Swimming pool special; Zwembadspecial

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    This issue includes a few articles and messages on the use of heat pump systems in swimming pools. [Dutch] Dit nummer bevat onder meer een paar artikelen over het gebruik van warmtepompsystemen in zwembaden.

  11. Harbor seal vibrissa morphology suppresses vortex-induced vibrations.

    Science.gov (United States)

    Hanke, Wolf; Witte, Matthias; Miersch, Lars; Brede, Martin; Oeffner, Johannes; Michael, Mark; Hanke, Frederike; Leder, Alfred; Dehnhardt, Guido

    2010-08-01

    Harbor seals (Phoca vitulina) often live in dark and turbid waters, where their mystacial vibrissae, or whiskers, play an important role in orientation. Besides detecting and discriminating objects by direct touch, harbor seals use their whiskers to analyze water movements, for example those generated by prey fish or by conspecifics. Even the weak water movements left behind by objects that have passed by earlier can be sensed and followed accurately (hydrodynamic trail following). While scanning the water for these hydrodynamic signals at a swimming speed in the order of meters per second, the seal keeps its long and flexible whiskers in an abducted position, largely perpendicular to the swimming direction. Remarkably, the whiskers of harbor seals possess a specialized undulated surface structure, the function of which was, up to now, unknown. Here, we show that this structure effectively changes the vortex street behind the whiskers and reduces the vibrations that would otherwise be induced by the shedding of vortices from the whiskers (vortex-induced vibrations). Using force measurements, flow measurements and numerical simulations, we find that the dynamic forces on harbor seal whiskers are, by at least an order of magnitude, lower than those on sea lion (Zalophus californianus) whiskers, which do not share the undulated structure. The results are discussed in the light of pinniped sensory biology and potential biomimetic applications.

  12. Geneva 24 hours swim

    CERN Document Server

    2003-01-01

    The 18th edition of the Geneva 24 hours swim competition will take place at the Vernets Swimming Pool on the 4th and 5th of October. More information and the results of previous years are given at: http://www.carouge-natation.com/24_heures/home_24_heures.htm Last year, CERN obtained first position in the inter-company category with a total of 152.3 kms swam by 45 participants. We are counting on your support to repeat this excellent performance this year. For those who would like to train, the Livron swimming pool in Meyrin is open as from Monday the 8th September. For further information please do not hesitate to contact us. Gino de Bilio and Catherine Delamare

  13. Geneva 24 Hours Swim

    CERN Document Server

    2003-01-01

    The 18th edition of the Geneva 24 hours swim competition will take place at the Vernets Swimming Pool on the 4th and 5th of October. More information and the results of previous years are given at: http://www.carouge-natation.com/24_heures/home_24_heures.htm Last year, CERN obtained first position in the inter-company category with a total of 152.3 kms swam by 45 participants. We are counting on your support to repeat this excellent performance this year. For those who would like to train, the Livron swimming pool in Meyrin is open as from Monday the 8th September. For further information please do not hesitate to contact us. Gino de Bilio and Catherine Delamare

  14. Swimming Pools and Molluscum Contagiosum

    Science.gov (United States)

    ... Travelers’ Health: Smallpox & Other Orthopoxvirus-Associated Infections Poxvirus Swimming Pools Recommend on Facebook Tweet Share Compartir The ... often ask if molluscum virus can spread in swimming pools. There is also concern that it can ...

  15. 2012 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  16. Healthy Swimming/Recreational Water

    Science.gov (United States)

    ... Medical Professionals En Español Publications, Data, & Statistics Healthy Swimming Resources Health Promotion Materials Find Your State Training & ... Announcements Outbreak Response Toolkits CDC at Work: Healthy Swimming Fast Facts Index of Water-Related Topics Model ...

  17. Stirring by swimming bodies

    International Nuclear Information System (INIS)

    Thiffeault, Jean-Luc; Childress, Stephen

    2010-01-01

    We consider the stirring of an inviscid fluid caused by the locomotion of bodies through it. The swimmers are approximated by non-interacting cylinders or spheres moving steadily along straight lines. We find the displacement of fluid particles caused by the nearby passage of a swimmer as a function of an impact parameter. We use this to compute the effective diffusion coefficient from the random walk of a fluid particle under the influence of a distribution of swimming bodies. We compare with the results of simulations. For typical sizes, densities and swimming velocities of schools of krill, the effective diffusivity in this model is five times the thermal diffusivity. However, we estimate that viscosity increases this value by two orders of magnitude.

  18. Swimming education in Australian society.

    OpenAIRE

    Lynch, TJ

    2014-01-01

    Abstract: The purpose of this paper is to explore a community swimming program using autoethnography qualitative research. Autoethnography is an approach to research and writing that seeks to describe and systematically analyze (graphy) personal experience (auto) in order to understand cultural experience (ethno) (Ellis 2004; Holman Jones 2005). Through childhood reflection of lived swimming experiences, and adult life reflection of lived swimming teaching experiences as a primary school teac...

  19. Pearl Harbor Biological Survey

    Science.gov (United States)

    1974-08-30

    Pearl Harbor also receives Irrigation tailgate waters from the Oahu Sug- ar Company, Industrial waste waters from the Prlmo Brewery , and heated waters...34Observations of the Cell Structure of Salt Fingers", J. Fluid Mech. 41:4, pp 707-719. ~) 3.3-79 ,’:•.-. ^ IV s’V- EFFECTS OF SHIP ACTIVITY Paul L...anticyclonic) death assemblage - in this report, an assemblage (q.v.) of remains (such as shells or bones ) from a naturally occurring association of living

  20. Paramecia swimming in viscous flow

    Science.gov (United States)

    Zhang, P.; Jana, S.; Giarra, M.; Vlachos, P. P.; Jung, S.

    2015-12-01

    Ciliates like Paramecia exhibit fore-aft asymmetry in their body shapes, and preferentially swim in the direction of the slender anterior rather than the wider posterior. However, the physical reasons for this preference are not well understood. In this work, we propose that specific features of the fluid flow around swimming Paramecia confer some energetic advantage to the preferred swimming direction. Therefore, we seek to understand the effects of body asymmetry and swimming direction on the efficiency of swimming and the flux of fluid into the cilia layer (and thus of food into the oral groove), which we assumed to be primary factors in the energy budgets of these organisms. To this end, we combined numerical techniques (the boundary element method) and laboratory experiments (micro particle image velocimetry) to develop a quantitative model of the flow around a Paramecium and investigate the effect of the body shape on the velocity fields, as well as on the swimming and feeding behaviors. Both simulation and experimental results show that velocity fields exhibit fore-aft asymmetry. Moreover, the shape asymmetry revealed an increase of the fluid flux into the cilia layer compared to symmetric body shapes. Under the assumption that cilia fluid intake and feeding efficiency are primary factors in the energy budgets of Paramecia, our model predicts that the anterior swimming direction is energetically favorable to the posterior swimming direction.

  1. Swimming activity in marine fish.

    Science.gov (United States)

    Wardle, C S

    1985-01-01

    Marine fish are capable of swimming long distances in annual migrations; they are also capable of high-speed dashes of short duration, and they can occupy small home territories for long periods with little activity. There is a large effect of fish size on the distance fish migrate at slow swimming speeds. When chased by a fishing trawl the effect of fish size on swimming performance can decide their fate. The identity and thickness of muscle used at each speed and evidence for the timing of myotomes used during the body movement cycle can be detected using electromyogram (EMG) electrodes. The cross-sectional area of muscle needed to maintain different swimming speeds can be predicted by relating the swimming drag force to the muscle force. At maximum swimming speed one completed cycle of swimming force is derived in sequence from the whole cross-sectional area of the muscles along the two sides of the fish. This and other aspects of the swimming cycle suggest that each myotome might be responsible for generating forces involved in particular stages of the tail sweep. The thick myotomes at the head end shorten during the peak thrust of the tail blade whereas the thinner myotomes nearer the tail generate stiffness appropriate for transmission of these forces and reposition the tail for the next cycle.

  2. The Impact of Baby Swimming on Introductory and Elementary Swimming Training

    OpenAIRE

    Břízová, Gabriela

    2007-01-01

    THESIS ANNOTATION Title: The Impact of Baby Swimming on Introductory and Elementary Swimming Training Aim: To assess the impact of 'baby swimming' on the successfulness in introductory and partly in elementary swimming training, and to find out whether also other circumstances (for example the length of attendance at 'baby swimming') have some influence on introductory swimming training. Methods: We used a questionnaire method for the parents of children who had attended 'baby swimming' and f...

  3. Swimming level of pupils from elementary schools with own swimming pool

    OpenAIRE

    Zálupská, Klára

    2012-01-01

    Title: Swimming level of pupils from primary school with private swimming pool. Work objectives: The aim is to identify assess level of swimming of pupils from first to ninth grade of primary school with a private pool in Chomutov district using continuous swimming test with regular swimming lessons, which is started in the first grade and persists until the ninth grade. The condition was organizing a school swimming lessons once a week for 45 minutes in all grades. Methodology: Swimming leve...

  4. Grays Harbor Paper

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, B. [Grays Harbor Paper, Hoquiam, WA (United States)

    2009-07-01

    Wood waste biomass boilers are used at Grays Harbor Paper in Hoquiam, Washington. This presentation showed that large volumes of biomass are left after a traditional clearcut. The opportunities and challenges of collecting branches, tops and stumps from this wet coastal climate were outlined. The paper described some of the low-tech methods for picking up branches, stumps and woody debris. It included several photographs of custom logging machines for timber harvest, including a brush grapple slasher, a shearer shovel, chippers, grinders, slicesaws, trucks, trailers and caterpillar log loaders for handling slash. The slash recovery program relies on innovative harvesting machines that convert scattered logging slash into bundles that can be easily collected, transported, and stored for use in existing facilities that utilize wood fiber for fuel. figs.

  5. Backfitting swimming pool reactors

    International Nuclear Information System (INIS)

    Roebert, G.A.

    1978-01-01

    Calculations based on measurements in a critical assembly, and experiments to disclose fuel element surface temperatures in case of accidents like stopping of primary coolant flow during full power operation, have shown that the power of the swimming pool type research reactor FRG-2 (15 MW, operating since 1967) might be raised to 21 MW within the present rules of science and technology, without major alterations of the pool buildings and the cooling systems. A backfitting program is carried through to adjust the reactor control systems of FRG-2 and FRG-1 (5 MW, housed in the same reactor hall) to the present safety rules and recommendations, to ensure FRG-2 operation at 21 MW for the next decade. (author)

  6. Threshold received sound pressure levels of single 1-2 kHz and 6-7 kHz up-sweeps and down-sweeps causing startle responses in a harbor porpoise (Phocoena phocoena)

    NARCIS (Netherlands)

    Kastelein, R.A.; Steen, N.; Gransier, R.; Wensveen, P.J.; Jong, C.A.F. de

    2012-01-01

    Mid-frequency and low-frequency sonar systems produce frequency-modulated sweeps which may affect harbor porpoises. To study the effect of sweeps on behavioral responses (specifically startle responses, which we define as sudden changes in swimming speed and/or direction), a harbor porpoise in a

  7. Swimming Performance and Metabolism of Golden Shiners

    Science.gov (United States)

    The swimming ability and metabolism of golden shiners, Notemigonus crysoleucas, was examined using swim tunnel respirometery. The oxygen consumption and tail beat frequencies at various swimming speeds, an estimation of the standard metabolic rate, and the critical swimming speed (Ucrit) was determ...

  8. 21 CFR 1250.89 - Swimming pools.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Swimming pools. 1250.89 Section 1250.89 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.89 Swimming pools. (a) Fill and draw swimming pools shall not be installed or used. (b) Swimming pools of the recirculation type shall be...

  9. Swimming ability and physiological response to swimming fatigue in ...

    African Journals Online (AJOL)

    The swimming endurance of kuruma shrimp, Marsupenaeus japonicus (11.04 ± 2.43 g) at five swimming speeds (23.0, 26.7, 31.0, 34.6 and 38.6 cm s-1) was determined in a circulating flume at 25.7 ± 0.7°C. The plasma glucose and total protein, hepatopancreas and pleopods muscle glycogen concentrations were ...

  10. Swimming literacy field hockey woman player ground.

    OpenAIRE

    Baštová, Miroslava

    2012-01-01

    Title: Swimming literacy field hockey woman player ground. Objectives: To obtain and analyze data on the level ground swimming literacy field hockey woman player. Their perception swimming literacy for life, the use of non-specific regeneration and as a training resource. Methods: Analysis of scientific literature, survey, case study, data analysis and graphical presentation of results. Results of the work: field hockey player as swimming literate, benefits swimming but not used as a means of...

  11. Free Swimming in Ground Effect

    Science.gov (United States)

    Cochran-Carney, Jackson; Wagenhoffer, Nathan; Zeyghami, Samane; Moored, Keith

    2017-11-01

    A free-swimming potential flow analysis of unsteady ground effect is conducted for two-dimensional airfoils via a method of images. The foils undergo a pure pitching motion about their leading edge, and the positions of the body in the streamwise and cross-stream directions are determined by the equations of motion of the body. It is shown that the unconstrained swimmer is attracted to a time-averaged position that is mediated by the flow interaction with the ground. The robustness of this fluid-mediated equilibrium position is probed by varying the non-dimensional mass, initial conditions and kinematic parameters of motion. Comparisons to the foil's fixed-motion counterpart are also made to pinpoint the effect that free swimming near the ground has on wake structures and the fluid-mediated forces over time. Optimal swimming regimes for near-boundary swimming are determined by examining asymmetric motions.

  12. System Wide Information Management (SWIM)

    Science.gov (United States)

    Hritz, Mike; McGowan, Shirley; Ramos, Cal

    2004-01-01

    This viewgraph presentation lists questions regarding the implementation of System Wide Information Management (SWIM). Some of the questions concern policy issues and strategies, technology issues and strategies, or transition issues and strategies.

  13. Grundfoss: Chlorination of Swimming Pools

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

    1998-01-01

    Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

  14. A Simple Method for Determination of Critical Swimming Velocity in Swimming Flume

    OpenAIRE

    高橋, 繁浩; 若吉, 浩二; Shigehiro, TAKAHASHI; Kohji, WAKAYOSHI; 中京大学; 奈良教育大学教育学部

    2001-01-01

    The purpose of this study was to investigate a simple method for determination of critical swimming velocity (Vcri). Vcri is defined by Wakayoshi et al. (1992) as the swimming speed which could theoretically be maintained forever without exhaustion, and is expressed as the slope of a regression line between swimming distance (D) and swimming time (T) obtained at various swimming speeds. To determine Vcri, 20 well-trained swimmers were measured at several swimming speeds ranging from 1.25 m/se...

  15. Swimming with the Shoal

    Science.gov (United States)

    Childs, Ann

    2017-10-01

    This article responds to Yuli Rahmawati and Peter Charles Taylor's piece and explores my role as a science teacher, science teacher educator and researcher in two contexts, Sierra Leone and Bhutan. In the first part of the article I reflect on my 3 years as a science teacher in Sierra Leone and demonstrate resonances with Yuli's accounts of culture shock and with her positioning of herself in a third space. I also reflect on the importance of colleagues in helping me reshape my identity as a science teacher in this new context. The second part of the article reflects on much shorter periods of time in Bhutan and my work as a teacher educator and researcher where, unlike Sierra Leone, it was not possible because of the short periods I worked there, to occupy a third space. I close by discussing how in Bhutan, but also Sierra Leone, collaboration with colleagues allowed me to contribute my own expertise, despite my lack of a deep understanding of the cultural context, in a way that was as valuable as possible. I liken this way of collaborative working in my professional life as `swimming with the shoal'.

  16. Solar swimming pool

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    This report examines the feasibility of using solar collectors to heat the water in a previously unheated outdoor swimming pool. The solar system is used in conjunction with a pool blanket, to conserve heat when the pool is not in use. Energy losses through evaporation can be reduced by as much as 70% by a pool blanket. A total of 130 m{sup 2} of highly durable black synthetic collectors were installed on a support structure at a 30{degree} angle from the horizontal, oriented to the south. Circulation of pool water though the collectors, which is controlled by a differential thermostat, was done with the existing pool pump. Before installation the pool temperature averaged 16{degree}C; after installation it ranged from 20{degree} to 26{degree}C. It was hard to distinguish how much pool heating was due to the solar system and how much heat was retained by the pool blanket. However, the pool season was extended by five weeks and attendance tripled. 2 figs.

  17. Is paramecium swimming autonomic?

    Science.gov (United States)

    Bandyopadhyay, Promode R.; Toplosky, Norman; Hansen, Joshua

    2010-11-01

    We seek to explore if the swimming of paramecium has an underlying autonomic mechanism. Such robotic elements may be useful in capturing the disturbance field in an environment in real time. Experimental evidence is emerging that motion control neurons of other animals may be present in paramecium as well. The limit cycle determined using analog simulation of the coupled nonlinear oscillators of olivo-cerebellar dynamics (ieee joe 33, 563-578, 2008) agrees with the tracks of the cilium of a biological paramecium. A 4-motor apparatus has been built that reproduces the kinematics of the cilium motion. The motion of the biological cilium has been analyzed and compared with the results of the finite element modeling of forces on a cilium. The modeling equates applied torque at the base of the cilium with drag, the cilium stiffness being phase dependent. A low friction pendulum apparatus with a multiplicity of electromagnetic actuators is being built for verifying the maps of the attractor basin computed using the olivo-cerebellar dynamics for different initial conditions. Sponsored by ONR 33.

  18. Hydrodynamic advantages of swimming by salp chains.

    Science.gov (United States)

    Sutherland, Kelly R; Weihs, Daniel

    2017-08-01

    Salps are marine invertebrates comprising multiple jet-propelled swimming units during a colonial life-cycle stage. Using theory, we show that asynchronous swimming with multiple pulsed jets yields substantial hydrodynamic benefit due to the production of steady swimming velocities, which limit drag. Laboratory comparisons of swimming kinematics of aggregate salps ( Salpa fusiformis and Weelia cylindrica ) using high-speed video supported that asynchronous swimming by aggregates results in a smoother velocity profile and showed that this smoother velocity profile is the result of uncoordinated, asynchronous swimming by individual zooids. In situ flow visualizations of W. cylindrica swimming wakes revealed that another consequence of asynchronous swimming is that fluid interactions between jet wakes are minimized. Although the advantages of multi-jet propulsion have been mentioned elsewhere, this is the first time that the theory has been quantified and the role of asynchronous swimming verified using experimental data from the laboratory and the field. © 2017 The Author(s).

  19. Alaska Harbor Seal Glacial Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Floating glacial ice serves as a haul-out substrate for a significant number (10-15%) of Alaskan harbor seals, and thus surveying tidewater glacial fjords is an...

  20. Swimming and other activities: applied aspects of fish swimming performance

    Science.gov (United States)

    Castro-Santos, Theodore R.; Farrell, A.P.

    2011-01-01

    Human activities such as hydropower development, water withdrawals, and commercial fisheries often put fish species at risk. Engineered solutions designed to protect species or their life stages are frequently based on assumptions about swimming performance and behaviors. In many cases, however, the appropriate data to support these designs are either unavailable or misapplied. This article provides an overview of the state of knowledge of fish swimming performance – where the data come from and how they are applied – identifying both gaps in knowledge and common errors in application, with guidance on how to avoid repeating mistakes, as well as suggestions for further study.

  1. Water Evaporation in Swimming Baths

    DEFF Research Database (Denmark)

    Hyldgård, Carl-Erik

    This paper is publishing measuring results from models and full-scale baths of the evaporation in swimming baths, both public baths and retraining baths. Moreover, the heat balance of the basin water is measured. In addition the full-scale measurements have given many experiences which are repres......This paper is publishing measuring results from models and full-scale baths of the evaporation in swimming baths, both public baths and retraining baths. Moreover, the heat balance of the basin water is measured. In addition the full-scale measurements have given many experiences which...... are represented in instructions for carrying out and running swimming baths. If you follow the instructions you can achieve less investments, less heat consumption and a better comfort to the bathers....

  2. Paramecium swimming in capillary tube

    Science.gov (United States)

    Jana, Saikat; Um, Soong Ho; Jung, Sunghwan

    2012-04-01

    Swimming organisms in their natural habitat need to navigate through a wide range of geometries and chemical environments. Interaction with boundaries in such situations is ubiquitous and can significantly modify the swimming characteristics of the organism when compared to ideal laboratory conditions. We study the different patterns of ciliary locomotion in glass capillaries of varying diameter and characterize the effect of the solid boundaries on the velocities of the organism. Experimental observations show that Paramecium executes helical trajectories that slowly transition to straight lines as the diameter of the capillary tubes decreases. We predict the swimming velocity in capillaries by modeling the system as a confined cylinder propagating longitudinal metachronal waves that create a finite pressure gradient. Comparing with experiments, we find that such pressure gradient considerations are necessary for modeling finite sized ciliary organisms in restrictive geometries.

  3. Optimal swimming of a sheet.

    Science.gov (United States)

    Montenegro-Johnson, Thomas D; Lauga, Eric

    2014-06-01

    Propulsion at microscopic scales is often achieved through propagating traveling waves along hairlike organelles called flagella. Taylor's two-dimensional swimming sheet model is frequently used to provide insight into problems of flagellar propulsion. We derive numerically the large-amplitude wave form of the two-dimensional swimming sheet that yields optimum hydrodynamic efficiency: the ratio of the squared swimming speed to the rate-of-working of the sheet against the fluid. Using the boundary element method, we show that the optimal wave form is a front-back symmetric regularized cusp that is 25% more efficient than the optimal sine wave. This optimal two-dimensional shape is smooth, qualitatively different from the kinked form of Lighthill's optimal three-dimensional flagellum, not predicted by small-amplitude theory, and different from the smooth circular-arc-like shape of active elastic filaments.

  4. Swimming in an Unsteady World

    Science.gov (United States)

    Koehl, M. A. R.

    2016-02-01

    When animals swim in marine habitats, the water through which they move is usually flowing. Therefore, an important part of understanding the physics of how animals swim in nature is determining how they interact with the fluctuating turbulent water currents in their environment. The research systems we have been using to address this question are microscopic marine animals swimming in turbulent, wavy water flow over spatially-complex communities of organisms growing on surfaces. Field measurements of water motion were used to design realistic turbulent flow in a laboratory wave-flume over different substrata, particle-image velocimetry was used to measure fine-scale, rapidly-varying water velocity vector fields, and planar laser-induced fluorescence was used to measure concentrations of chemical cues from the substratum. We used individual-based models of small animals swimming in this unsteady flow to determine how their trajectories and contacts with substrata were affected by their locomotion through the water, rotation by local shear, response to odors, and transport by ambient flow. We found that the shears, accelerations, and odor concentrations encountered by small swimmers fluctuate rapidly, with peaks much higher than mean values lasting fractions of a second. We identified ways in which the behavior of small, weak swimmers can bias how they are transported by ambient flow (e.g. sinking during brief encounters with shear or odor enhances settlement onto substrata below, whereas constant swimming enhances contact with surfaces above or beside larvae). Although microscopic organisms swim slowly relative to ambient water flow, their locomotory behavior in response to the rapidly-fluctuating shears and odors they encounter can affect where they are transported by ambient water movement.

  5. Surface Waters Information Management System (SWIMS)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Surface Waters Information Management System (SWIMS) has been designed to meet multi-agency hydrologic database needs for Kansas. The SWIMS project was supported...

  6. 43 CFR 423.36 - Swimming.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Swimming. 423.36 Section 423.36 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR... Swimming. (a) You may swim, wade, snorkel, scuba dive, raft, or tube at your own risk in Reclamation waters...

  7. 36 CFR 331.10 - Swimming.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Swimming. 331.10 Section 331.10 Parks, Forests, and Public Property CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY REGULATIONS..., KENTUCKY AND INDIANA § 331.10 Swimming. Swimming is prohibited unless authorized in writing by the District...

  8. 36 CFR 327.5 - Swimming.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Swimming. 327.5 Section 327.5 Parks, Forests, and Public Property CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY RULES AND REGULATIONS... Swimming. (a) Swimming, wading, snorkeling or scuba diving at one's own risk is permitted, except at...

  9. 1968 Listing of Swimming Pool Equipment.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI. Testing Lab.

    An up-to-date listing of swimming pool equipment including--(1) companies authorized to display the National Sanitation Foundation seal of approval, (2) equipment listed as meeting NSF swimming pool equipment standards relating to diatomite type filters, (3) equipment listed as meeting NSF swimming pool equipment standard relating to sand type…

  10. Undulatory fish swimming : from muscles to flow

    NARCIS (Netherlands)

    Müller, U.K.; Leeuwen, van J.L.

    2006-01-01

    Undulatory swimming is employed by many fish for routine swimming and extended sprints. In this biomechanical review, we address two questions: (i) how the fish's axial muscles power swimming; and (ii) how the fish's body and fins generate thrust. Fish have adapted the morphology of their axial

  11. Geoscience rediscovers Phoenicia's buried harbors

    Science.gov (United States)

    Marriner, Nick; Morhange, Christophe; Doumet-Serhal, Claude; Carbonel, Pierre

    2006-01-01

    After centuries of archaeological debate, the harbors of Phoenicia's two most important city states, Tyre and Sidon, have been rediscovered, and including new geoarcheological results reveal how, where, and when they evolved after their Bronze Age foundations. The early ports lie beneath their present urban centers, and we have indentified four harbor phases. (1) During the Bronze Age, Tyre and Sidon were characterized by semi-open marine coves that served as protoharbors. (2) Biostratigraphic and lithostratigraphic data indicate the presence of early artificial basins after the first millennium B.C. (3) The harbors reached their apogees during the Greco-Roman and Byzantine periods. (4) Silting up and coastal progradation led to burial of the medieval basins, lost until now.

  12. The influence of elements of synchronized swimming on technique of the selected swimming strokes

    OpenAIRE

    Široký, Michal

    2015-01-01

    Title: The influence of elements of synchronized swimming on technique of the selected swimming strokes Objectives: The objective of the thesis is to assess the effect of the elements of synchronized swimming at improving the techniques of swimming. Methods: The results were detected by overt observation with active participation and subsequent scaling on the ordinal scale 1 to 5. Results: The results show that the influence of the elements of synchronized swimming on improving the technique ...

  13. The Effect of Swimming Experience on Acquisition and Retention of Swimming-Based Taste Aversion Learning in Rats

    Science.gov (United States)

    Masaki, Takahisa; Nakajima, Sadahiko

    2010-01-01

    Swimming endows rats with an aversion to a taste solution consumed before swimming. The present study explored whether the experience of swimming before or after the taste-swimming trials interferes with swimming-based taste aversion learning. Experiment 1 demonstrated that a single preexposure to 20 min of swimming was as effective as four or…

  14. Fluid Mechanics of Fish Swimming

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 1. Fluid Mechanics of Fish Swimming - Lift-based Propulsion. Jaywant H Arakeri. General Article Volume 14 Issue 1 January 2009 pp 32-46. Fulltext. Click here to view fulltext PDF. Permanent link:

  15. Sodium bicarbonate improves swimming performance.

    Science.gov (United States)

    Lindh, A M; Peyrebrune, M C; Ingham, S A; Bailey, D M; Folland, J P

    2008-06-01

    Sodium bicarbonate ingestion has been shown to improve performance in single-bout, high intensity events, probably due to an increase in buffering capacity, but its influence on single-bout swimming performance has not been investigated. The effects of sodium bicarbonate supplementation on 200 m freestyle swimming performance were investigated in elite male competitors. Following a randomised, double blind counterbalanced design, 9 swimmers completed maximal effort swims on 3 separate occasions: a control trial (C); after ingestion of sodium bicarbonate (SB: NaHCO3 300 mg . kg (-1) body mass); and after ingestion of a placebo (P: CaCO3 200 mg . kg (-1) body mass). The SB and P agents were packed in gelatine capsules and ingested 90 - 60 min prior to each 200 m swim. Mean 200 m performance times were significantly faster for SB than C or P (1 : 52.2 +/- 4.7; 1 : 53.7 +/- 3.8; 1 : 54.0 +/- 3.6 min : ss; p bicarbonate were all elevated pre-exercise in the SB compared to C and P trials (p < 0.05). Post-200 m blood lactate concentrations were significantly higher following the SB trial compared with P and C (p < 0.05). It was concluded that SB supplementation can improve 200 m freestyle performance time in elite male competitors, most likely by increasing buffering capacity.

  16. The hydrodynamics of swimming microorganisms

    International Nuclear Information System (INIS)

    Lauga, Eric; Powers, Thomas R

    2009-01-01

    Cell motility in viscous fluids is ubiquitous and affects many biological processes, including reproduction, infection and the marine life ecosystem. Here we review the biophysical and mechanical principles of locomotion at the small scales relevant to cell swimming, tens of micrometers and below. At this scale, inertia is unimportant and the Reynolds number is small. Our emphasis is on the simple physical picture and fundamental flow physics phenomena in this regime. We first give a brief overview of the mechanisms for swimming motility, and of the basic properties of flows at low Reynolds number, paying special attention to aspects most relevant for swimming such as resistance matrices for solid bodies, flow singularities and kinematic requirements for net translation. Then we review classical theoretical work on cell motility, in particular early calculations of swimming kinematics with prescribed stroke and the application of resistive force theory and slender-body theory to flagellar locomotion. After examining the physical means by which flagella are actuated, we outline areas of active research, including hydrodynamic interactions, biological locomotion in complex fluids, the design of small-scale artificial swimmers and the optimization of locomotion strategies.

  17. Shape Optimization of Swimming Sheets

    Energy Technology Data Exchange (ETDEWEB)

    Wilkening, J.; Hosoi, A.E.

    2005-03-01

    The swimming behavior of a flexible sheet which moves by propagating deformation waves along its body was first studied by G. I. Taylor in 1951. In addition to being of theoretical interest, this problem serves as a useful model of the locomotion of gastropods and various micro-organisms. Although the mechanics of swimming via wave propagation has been studied extensively, relatively little work has been done to define or describe optimal swimming by this mechanism.We carry out this objective for a sheet that is separated from a rigid substrate by a thin film of viscous Newtonian fluid. Using a lubrication approximation to model the dynamics, we derive the relevant Euler-Lagrange equations to optimize swimming speed and efficiency. The optimization equations are solved numerically using two different schemes: a limited memory BFGS method that uses cubic splines to represent the wave profile, and a multi-shooting Runge-Kutta approach that uses the Levenberg-Marquardt method to vary the parameters of the equations until the constraints are satisfied. The former approach is less efficient but generalizes nicely to the non-lubrication setting. For each optimization problem we obtain a one parameter family of solutions that becomes singular in a self-similar fashion as the parameter approaches a critical value. We explore the validity of the lubrication approximation near this singular limit by monitoring higher order corrections to the zeroth order theory and by comparing the results with finite element solutions of the full Stokes equations.

  18. Pre-task music improves swimming performance.

    Science.gov (United States)

    Smirmaul, B P; Dos Santos, R V; Da Silva Neto, L V

    2015-12-01

    The purpose of this study was to investigate the effects of pre-task music on swimming performance and other psychological variables. A randomized counterbalanced within-subjects (experimental and control condition) design was employed. Eighteen regional level male swimmers performed two 200-m freestyle swimming time trials. Participants were exposed to either 5 minutes of self-selected music (pre-task music condition) or 5 minutes of silence (control condition) and, after 1 minute, performed the swimming task. Swimming time was significantly shorter (-1.44%) in the pre-task music condition. Listening to pre-task music increased motivation to perform the swimming task, while arousal remained unchanged. While fatigue increased after the swimming task in both conditions, vigor, ratings of perceived exertion and affective valence were unaltered. It is concluded, for the first time, that pre-task music improves swimming performance.

  19. Heart rate variability and swimming.

    Science.gov (United States)

    Koenig, Julian; Jarczok, Marc N; Wasner, Mieke; Hillecke, Thomas K; Thayer, Julian F

    2014-10-01

    Professionals in the domain of swimming have a strong interest in implementing research methods in evaluating and improving training methods to maximize athletic performance and competitive outcome. Heart rate variability (HRV) has gained attention in research on sport and exercise to assess autonomic nervous system activity underlying physical activity and sports performance. Studies on swimming and HRV are rare. This review aims to summarize the current evidence on the application of HRV in swimming research and draws implications for future research. A systematic search of databases (PubMed via MEDLINE, PSYNDEX and Embase) according to the PRISMA statement was employed. Studies were screened for eligibility on inclusion criteria: (a) empirical investigation (HRV) in humans (non-clinical); (b) related to swimming; (c) peer-reviewed journal; and (d) English language. The search revealed 194 studies (duplicates removed), of which the abstract was screened for eligibility. Fourteen studies meeting the inclusion criteria were included in the review. Included studies broadly fell into three classes: (1) control group designs to investigate between-subject differences (i.e. swimmers vs. non-swimmers, swimmers vs. other athletes); (2) repeated measures designs on within-subject differences of interventional studies measuring HRV to address different modalities of training or recovery; and (3) other studies, on the agreement of HRV with other measures. The feasibility and possibilities of HRV within this particular field of application are well documented within the existing literature. Future studies, focusing on translational approaches that transfer current evidence in general practice (i.e. training of athletes) are needed.

  20. Cetacean Swimming with Prosthetic Limbs

    Science.gov (United States)

    Bode-Oke, Ayodeji; Ren, Yan; Dong, Haibo; Fish, Frank

    2016-11-01

    During entanglement in fishing gear, dolphins can suffer abrasions and amputations of flukes and fins. As a result, if the dolphin survives the ordeal, swimming performance is altered. Current rehabilitation technques is the use of prosthesis to regain swimming ability. In this work, analyses are focused on two dolphins with locomotive impairment; Winter (currently living in Clearwater Marine Aquarium in Florida) and Fuji (lived in Okinawa Churaumi Aquarium in Japan). Fuji lost about 75% of its fluke surface to necrosis (death of cells) and Winter lost its tail due to amputation. Both dolphins are aided by prosthetic tails that mimic the shape of a real dolphin tail. Using 3D surface reconstruction techniques and a high fidelity Computational Fluid Dynamics (CFD) flow solver, we were able to elucidate the kinematics and hydrodynamics and fluke deformation of these swimmers to clarify the effectiveness of prostheses in helping the dolphins regain their swimming ability. Associated with the performance, we identified distinct features in the wake structures that can explain this gap in the performance compared to a healthy dolphin. This work was supported by ONR MURI Grant Number N00014-14-1-0533.

  1. 77 FR 19967 - Safety Zone, Port of Dutch Harbor; Dutch Harbor, AK

    Science.gov (United States)

    2012-04-03

    ...-AA00 Safety Zone, Port of Dutch Harbor; Dutch Harbor, AK AGENCY: Coast Guard, DHS. ACTION: Notice of proposed rulemaking. SUMMARY: The Coast Guard proposes temporary safety zones in the Port of Dutch Harbor... Dutch Harbor, Alaska, and the adjacent territorial sea due to additional vessel traffic associated with...

  2. Army Engineers at Pearl Harbor

    Science.gov (United States)

    2011-01-01

    siblings, he was the grandson of David Belden Lyman—a Christian missionary from New England who settled in the Hilo , Hawaii area—and the descendent of...of Hawaii appeared over Oahu. Some headed for Ameri- can warships at Pearl Harbor and the planes on the ground at nearby Hickam Field; oth- ers...hit Schofield Barracks, Wheeler Field, and Bellows Field. USACE in Hawaii con- sisted of Soldier-engineers in the Army’s Hawaiian Depart- ment and

  3. Comparison of physical fitness tests in swimming

    OpenAIRE

    Dostálová, Sabina

    2015-01-01

    Title: Comparison of physical fitness tests in swimming. Objective: The aim of this thesis is to evaluate specific tests, used while testing selected physical abilities in swimming. By specific tests we mean tests realized in the water. Selected tests are intended for swim coaches, who train junior to senior age groups. Methods: The chosen method was a comparison of studies, that pursue selected specific tests. We created partial conclusions for every test by summing up the results of differe...

  4. Hydrodynamic attraction of swimming microorganisms by surfaces

    OpenAIRE

    Berke, Allison P.; Turner, Linda; Berg, Howard C.; Lauga, Eric

    2008-01-01

    Cells swimming in confined environments are attracted by surfaces. We measure the steady-state distribution of smooth-swimming bacteria (Escherichia coli) between two glass plates. In agreement with earlier studies, we find a strong increase of the cell concentration at the boundaries. We demonstrate theoretically that hydrodynamic interactions of the swimming cells with solid surfaces lead to their re-orientation in the direction parallel to the surfaces, as well as their attraction by the c...

  5. Swimming Performance of Adult Asian Carp: Field Assessment Using a Mobile Swim Tunnel

    Science.gov (United States)

    2016-08-01

    ERDC/TN ANSRP-16-1 August 2016 Approved for public release; distribution is unlimited. Swimming Performance of Adult Asian Carp: Field...Assessment Using a Mobile Swim Tunnel by Jan Jeffrey Hoover, Jay A. Collins, Alan W. Katzenmeyer, and K. Jack Killgore PURPOSE: Empirical swim speed...test in traditional laboratory swim tunnels. Biologists from the Engineer Research and Development Center (ERDC) Environmental Laboratory (EL), with

  6. 33 CFR 125.15 - Access to waterfront facilities, and port and harbor areas, including vessels and harbor craft...

    Science.gov (United States)

    2010-07-01

    ..., and port and harbor areas, including vessels and harbor craft therein. 125.15 Section 125.15....15 Access to waterfront facilities, and port and harbor areas, including vessels and harbor craft....09 to those waterfront facilities, and port and harbor areas, including vessels and harbor craft...

  7. Swimming dynamics of bidirectional artificial flagella

    NARCIS (Netherlands)

    Namdeo, S.; Khaderi, S. N.; Onck, P. R.

    2013-01-01

    We study magnetic artificial flagella whose swimming speed and direction can be controlled using light and magnetic field as external triggers. The dependence of the swimming velocity on the system parameters (e. g., length, stiffness, fluid viscosity, and magnetic field) is explored using a

  8. Basic Land Drills for Swimming Stroke Acquisition

    Science.gov (United States)

    Zhang, Peng

    2014-01-01

    Teaching swimming strokes can be a challenging task in physical education. The purpose of the article is to introduce 12 on land drills that can be utilized to facilitate the learning of swimming strokes, including elementary back stroke, sidestroke, front crawl, back stroke, breaststroke, and butterfly. Each drill consists of four components…

  9. Swimming and muscle structure in fish

    NARCIS (Netherlands)

    Spierts, I.L.Y.

    1999-01-01

    In this series of studies the relations between swimming behaviour of fish in general and extreme swimming responses in particular (called fast starts or escape responses) and the structure and ontogeny of the muscle system was investigated. Special attention was paid to relate functional

  10. Swimming level classification of young school age children and their success in a long distance swimming test

    OpenAIRE

    Nováková, Martina

    2010-01-01

    Title: Swimming level classification of young school age children and their success in a long distance swimming test Work objectives: The outcome of our work is comparison and evaluation of the initial and final swimming lenght in a test of long distance swimming. This test is taken during one swimming course. Methodology: Data which were obtained by testing a certain group of people and were statistically processed, showed the swimming level and performance of the young school age children. ...

  11. Strouhal number for free swimming

    Science.gov (United States)

    Saadat, Mehdi; van Buren, Tyler; Floryan, Daniel; Smits, Alexander; Haj-Hariri, Hossein

    2015-11-01

    In this work, we present experimental results to explore the implications of free swimming for Strouhal number (as an outcome) in the context of a simple model for a fish that consists of a 2D virtual body (source of drag) and a 2D pitching foil (source of thrust) representing cruising with thunniform locomotion. The results validate the findings of Saadat and Haj-Hariri (2012): for pitching foils thrust coefficient is a function of Strouhal number for all gaits having amplitude less than a certain critical value. Equivalently, given the balance of thrust and drag forces at cruise, Strouhal number is only a function of the shape, i.e. drag coefficient and area, and essentially a constant for high enough swimming speeds for which the mild dependence of drag coefficient on the speed vanishes. Furthermore, a dimensional analysis generalizes the findings. A scaling analysis shows that the variation of Strouhal number with cruising speed is functionally related to the variation of body drag coefficient with speed. Supported by ONR MURI Grant N00014-14-1-0533.

  12. Swimming

    Science.gov (United States)

    ... back on them. Then you'll know what's coming. Water Parks Kids love water parks — and why shouldn't they? Wave pools, giant slides, and squirting fountains are a lot of fun. To stay safe, find out what each attraction is like and how deep the water is. ...

  13. swimming

    Science.gov (United States)

    Locations Recycling Sludge/Biosolids Solid Waste Watershed Protection Nonpoint Source Pollution Total Watershed Protection Wellhead Protection Funding Water and Waste Funding Drinking Water Funding Sanitary and Permit Oil and Gas Waste Management Water Rights All Permits/Forms (Alphabetical) All Permits/Forms (by

  14. Prey capture by freely swimming flagellates

    Science.gov (United States)

    Andersen, Anders; Dolger, Julia; Nielsen, Lasse Tor; Kiorboe, Thomas

    2017-11-01

    Flagellates are unicellular microswimmers that propel themselves using one or several beating flagella. Here, we explore the dependence of swimming kinematics and prey clearance rate on flagellar arrangement and determine optimal flagellar arrangements and essential trade-offs. To describe near-cell flows around freely swimming flagellates we consider a model in which the cell is represented by a no-slip sphere and each flagellum by a point force. For uniflagellates pulled by a single flagellum the model suggests that a long flagellum favors fast swimming, whereas high clearance rate is favored by a very short flagellum. For biflagellates with both a longitudinal and a transversal flagellum we explore the helical swimming kinematics and the prey capture sites. We compare our predictions with observations of swimming kinematics, prey capture, and flows around common marine flagellates. The Centre for Ocean Life is a VKR Centre of Excellence supported by the Villum Foundation.

  15. CRSMP Potential Harbor Borrow Sites 2012

    Data.gov (United States)

    California Natural Resource Agency — Harbor locations as identified originally in the California Shoreline Database compiled by Noble Consultants (Jon Moore) for California Department of Boating and...

  16. Swimming of the Honey Bees

    Science.gov (United States)

    Roh, Chris; Gharib, Morteza

    2016-11-01

    When the weather gets hot, nursing honey bees nudge foragers to collect water for thermoregulation of their hive. While on their mission to collect water, foragers sometimes get trapped on the water surface, forced to interact with a different fluid environment. In this study, we present the survival strategy of the honey bees at the air-water interface. A high-speed videography and shadowgraph were used to record the honey bees swimming. A unique thrust mechanism through rapid vibration of their wings at 60 to 150 Hz was observed. This material is based upon work supported by the National Science Foundation under Grant No. CBET-1511414; additional support by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469.

  17. 33 CFR 100.109 - Winter Harbor Lobster Boat Race, Winter Harbor, ME.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Winter Harbor Lobster Boat Race, Winter Harbor, ME. 100.109 Section 100.109 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.109 Winter Harbor...

  18. Krill (Meganyctiphanes norvegica) swim faster at night

    KAUST Repository

    Klevjer, Thor A.

    2011-05-01

    Krill are key members in marine food webs, and measurement of swimming speed is vital to assess their bioenergetic budgets, feeding, and encounters with predators. We document a consistent and marked diel signal in swimming speed of krill in their natural habitat that is not related to diel vertical migration. The results were obtained using a bottom-mounted, upward-looking echo sounder at 150-m depth in the Oslofjord, Norway, spanning 5 months from late autumn to spring at a temporal resolution of ~1–2 records s−1. Swimming speed was assessed using acoustic target tracking of individual krill. At the start of the registration period, both daytime and nocturnal average swimming speeds of Meganyctiphanes norvegica were ~ 3.5 cm s−1 (~ 1 body lengths ([bl] s−1) in waters with oxygen concentrations of ~ 15–20% O2 saturation. Following intrusion of more oxygenated water, nocturnal average swimming speeds increased to ~ 10 cm s−1 (~ 3 bl s−1), i.e., more than double that of daytime swimming speeds in the same period. We hypothesize that krill activity during the first period was limited by oxygen, and the enhanced swimming at night subsequent to the water renewal is due to increased feeding activity under lessened danger of predation in darkness.

  19. Krill (Meganyctiphanes norvegica) swim faster at night

    KAUST Repository

    Klevjer, Thor A.; Kaartvedt, Stein

    2011-01-01

    Krill are key members in marine food webs, and measurement of swimming speed is vital to assess their bioenergetic budgets, feeding, and encounters with predators. We document a consistent and marked diel signal in swimming speed of krill in their natural habitat that is not related to diel vertical migration. The results were obtained using a bottom-mounted, upward-looking echo sounder at 150-m depth in the Oslofjord, Norway, spanning 5 months from late autumn to spring at a temporal resolution of ~1–2 records s−1. Swimming speed was assessed using acoustic target tracking of individual krill. At the start of the registration period, both daytime and nocturnal average swimming speeds of Meganyctiphanes norvegica were ~ 3.5 cm s−1 (~ 1 body lengths ([bl] s−1) in waters with oxygen concentrations of ~ 15–20% O2 saturation. Following intrusion of more oxygenated water, nocturnal average swimming speeds increased to ~ 10 cm s−1 (~ 3 bl s−1), i.e., more than double that of daytime swimming speeds in the same period. We hypothesize that krill activity during the first period was limited by oxygen, and the enhanced swimming at night subsequent to the water renewal is due to increased feeding activity under lessened danger of predation in darkness.

  20. SWIM EVERYDAY TO KEEP DEMENTIA AWAY

    Directory of Open Access Journals (Sweden)

    Nirmal Singh

    2005-03-01

    Full Text Available A sound mind resides in a sound body. Many individuals with an active lifestyle show sharp mental skills at an advanced age. Regular exercise has been shown to exert numerous beneficial effects on brawn as well as brain. The present study was undertaken to evaluate the influence of swimming on memory of rodents. A specially designed hexagonal water maze was used for the swimming exposures of animals. The learning and memory parameters were measured using exteroceptive behavioral models such as Elevated plus-maze, Hebb-Williams maze and Passive avoidance apparatus. The rodents (rats and mice were divided into twelve groups. The swimming exposure to the rodents was for 10- minute period during each session and there were two swimming exposures on each day. Rats and mice were subjected to swimming for -15 and -30 consecutive days. Control group animals were not subjected to swimming during above period. The learning index and memory score of all the animals was recorded on 1st, 2nd, 15th, 16th, 30th and 31st day employing above exteroceptive models. It was observed that rodents that underwent swimming regularly for 30- days showed sharp memories, when tested on above behavioral models whereas, control group animals showed decline in memory scores. Those animals, which underwent swimming for 15- days only showed good memory on 16th day, which however, declined after 30-days. These results emphasize the role of regular physical exercise particularly swimming in the maintenance and promotion of brain functions. The underlying physiological mechanism for improvement of memory appears to be the result of enhanced neurogenesis.

  1. A Review of Swimming Cues and Tips for Physical Education

    Science.gov (United States)

    Higginson, Kelsey; Barney, David

    2016-01-01

    Swimming is a low-impact activity that causes little stress on joints so it can be done for a lifetime. Many teachers may wish to teach swimming but do not have cues or ideas for doing so. This article reviews swimming cues, relays and equipment that can help a physical education teacher include a swimming unit in their curriculum. Certification…

  2. Swimming and feeding of mixotrophic biflagellates

    DEFF Research Database (Denmark)

    Dölger, Julia; Nielsen, Lasse Tor; Kiørboe, Thomas

    2017-01-01

    Many unicellular flagellates are mixotrophic and access resources through both photosynthesis and prey capture. Their fitness depends on those processes as well as on swimming and predator avoidance. How does the flagellar arrangement and beat pattern of the flagellate affect swimming speed...... with variable position next to a no-slip sphere. Utilizing the observations and the model we find that puller force arrangements favour feeding, whereas equatorial force arrangements favour fast and quiet swimming. We determine the capture rates of both passive and motile prey, and we show that the flow...

  3. Guide for decontaminating swimming pool at schools

    International Nuclear Information System (INIS)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-01

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  4. Guide for decontaminating swimming pool at schools

    Energy Technology Data Exchange (ETDEWEB)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-15

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  5. The Suez Canal and the petroleum harbors

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    The Suez Canal is the second longest channel in the world and allows to save 60% of the travel time between the petroleum harbors of the Arabic peninsula and Europe. This short paper gives a summary of the main petroleum harbors activity along the channel from the Red sea to the Mediterranean sea. (J.S.)

  6. Factors influencing termination of swimming career of children at sport swimming classes

    OpenAIRE

    Pištěková, Petra

    2007-01-01

    Title: The Cause ofan Early End ofPupils' Swimming Career The aim of the thesis: Determination ofthe most frequent reasons for an early end ofpupils' swimming career. Method: The reasons for an early end ofpupils' swimming career were discovered by using questionnaires. Forty-five former pupils from special sports elementary schools were questioned and then the data were compared with available literature. Results: Research investigated changes in the most frequent reasons for an early end of...

  7. In situ swimming speed and swimming behaviour of fish feeding on the krill Meganyctiphanes norvegica

    OpenAIRE

    Onsrud, M. S. R.; Kaartvedt, Stein; Breien, M. T.

    2005-01-01

    In situ swimming speed and swimming behaviour of dielly migrating planktivorous fish were studied at a 120-m-deep location. Acoustic target tracking was performed using a hull-mounted transducer and submersible transducers located on the sea bottom and free hanging in the water column. The original data displayed a relationship between distance to transducer and swimming speed. A simplistic smoother applied during post-processing, appeared to break this relationship. Target tracki...

  8. Analysis of Sport Nutrition and Diet for Swimming Athletes

    OpenAIRE

    Jun An

    2014-01-01

    This current study analyzed nutrition and dietary structure of swimming athletes to clarify issues in nutrition and dietary structure of swimming athletes, based on which we designed achievable nutrition and diet strategies to equip the swimming athletes with the tools to achieve an adequate sport nutrition which helps them improve results. Firstly, we collected literatures about nutrition and diet of swimming athletes. Secondly, 40 swimming athletes were assigned to the test group and the co...

  9. Swimming Performance of Toy Robotic Fish

    Science.gov (United States)

    Petelina, Nina; Mendelson, Leah; Techet, Alexandra

    2015-11-01

    HEXBUG AquaBotsTM are a commercially available small robot fish that come in a variety of ``species''. These models have varying caudal fin shapes and randomly-varied modes of swimming including forward locomotion, diving, and turning. In this study, we assess the repeatability and performance of the HEXBUG swimming behaviors and discuss the use of these toys to develop experimental techniques and analysis methods to study live fish swimming. In order to determine whether these simple, affordable model fish can be a valid representation for live fish movement, two models, an angelfish and a shark, were studied using 2D Particle Image Velocimetry (PIV) and 3D Synthetic Aperture PIV. In a series of experiments, the robotic fish were either allowed to swim freely or towed in one direction at a constant speed. The resultant measurements of the caudal fin wake are compared to data from previous studies of a real fish and simplified flapping propulsors.

  10. Muscle dynamics in fish during steady swimming

    DEFF Research Database (Denmark)

    Shadwick, RE; Steffensen, JF; Katz, SL

    1998-01-01

    SYNOPSIS. Recent research in fish locomotion has been dominated by an interest in the dynamic mechanical properties of the swimming musculature. Prior observations have indicated that waves of muscle activation travel along the body of an undulating fish faster than the resulting waves of muscular...... position in swimming fish. Quantification of muscle contractile properties in cyclic contractions relies on in vitro experiments using strain and activation data collected in vivo. In this paper we discuss the relation between these parameters and body kinematics. Using videoradiographic data from swimming...... constant cross-section of red muscle along much of the body suggests that positive power for swimming is generated fairly uniformly along the length of the fish....

  11. Ingestion of swimming pool water by recreational

    Data.gov (United States)

    U.S. Environmental Protection Agency — Swimming pool water ingestion data. This dataset is associated with the following publication: Dufour, A., L. Wymer, M. Magnuson, T. Behymer, and R. Cantu. Ingestion...

  12. Swimming of Paramecium in confined channels

    Science.gov (United States)

    Jung, Sunghwan

    2012-02-01

    Many living organisms in nature have developed a few different swimming modes, presumably derived from hydrodynamic advantage. Paramecium is a ciliated protozoan covered by thousands of cilia with a few nanometers in diameter and tens of micro-meters in length and is able to exhibit both ballistic and meandering motions. First, we characterize ballistic swimming behaviors of ciliated microorganisms in glass capillaries of different diameters and explain the trajectories they trace out. We develop a theoretical model of an undulating sheet with a pressure gradient and discuss how it affects the swimming speed. Secondly, investigation into meandering swimmings within rectangular PDMS channels of dimension smaller than Paramecium length. We find that Paramecium executes a body-bend (an elastic buckling) using the cilia while it meanders. By considering an elastic beam model, we estimate and show the universal profile of forces it exerts on the walls. Finally, we discuss a few other locomotion of Paramecium in other extreme environments like gel.

  13. The Fluid Dynamics of Competitive Swimming

    Science.gov (United States)

    Wei, Timothy; Mark, Russell; Hutchison, Sean

    2014-01-01

    Nowhere in sport is performance so dependent on the interaction of the athlete with the surrounding medium than in competitive swimming. As a result, understanding (at least implicitly) and controlling (explicitly) the fluid dynamics of swimming are essential to earning a spot on the medal stand. This is an extremely complex, highly multidisciplinary problem with a broad spectrum of research approaches. This review attempts to provide a historical framework for the fluid dynamics-related aspects of human swimming research, principally conducted roughly over the past five decades, with an emphasis on the past 25 years. The literature is organized below to show a continuous integration of computational and experimental technologies into the sport. Illustrations from the authors' collaborations over a 10-year period, coupling the knowledge and experience of an elite-level coach, a lead biomechanician at USA Swimming, and an experimental fluid dynamicist, are intended to bring relevance and immediacy to the review.

  14. Anisotropic swim stress in active matter with nematic order

    Science.gov (United States)

    Yan, Wen; Brady, John F.

    2018-05-01

    Active Brownian particles (ABPs) transmit a swim pressure {{{\\Pi }}}{{swim}}=n\\zeta {D}{{swim}} to the container boundaries, where ζ is the drag coefficient, D swim is the swim diffusivity and n is the uniform bulk number density far from the container walls. In this work we extend the notion of the isotropic swim pressure to the anisotropic tensorial swim stress {{\\boldsymbol{σ }}}{{swim}}=-n\\zeta {{\\boldsymbol{D}}}{{swim}}, which is related to the anisotropic swim diffusivity {{\\boldsymbol{D}}}{{swim}}. We demonstrate this relationship with ABPs that achieve nematic orientational order via a bulk external field. The anisotropic swim stress is obtained analytically for dilute ABPs in both 2D and 3D systems. The anisotropy, defined as the ratio of the maximum to the minimum of the three principal stresses, is shown to grow exponentially with the strength of the external field. We verify that the normal component of the anisotropic swim stress applies a pressure {{{\\Pi }}}{{swim}}=-({{\\boldsymbol{σ }}}{{swim}}\\cdot {\\boldsymbol{n}})\\cdot {\\boldsymbol{n}} on a wall with normal vector {\\boldsymbol{n}}, and, through Brownian dynamics simulations, this pressure is shown to be the force per unit area transmitted by the active particles. Since ABPs have no friction with a wall, the difference between the normal and tangential stress components—the normal stress difference—generates a net flow of ABPs along the wall, which is a generic property of active matter systems.

  15. Experimental hydrodynamics of swimming in fishes

    Science.gov (United States)

    Tytell, Eric Daniel

    2005-11-01

    The great diversity of fish body shapes suggests that they have adapted to different selective pressures. For many fishes, the pressures include hydrodynamic demands: swimming efficiently or accelerating rapidly, for instance. However, the hydrodynamic advantages or disadvantages to specific morphologies are poorly understood. In particular, eels have been considered inefficient swimmers, but they migrate long distances without feeding, a task that requires efficient swimming. This dissertation, therefore, begins with an examination of the swimming hydrodynamics of American eels, Anguilla rostrata, at steady swimming speeds from 0.5 to 2 body lengths (L) per second and during accelerations from -1.4 to 1.3 L s -2. The final chapter examines the hydrodynamic effects of body shape directly by describing three-dimensional flow around swimming bluegill sunfish, Lepomis macrochirus. In all chapters, flow is quantified using digital particle image velocimetry, and simultaneous kinematics are measured from high-resolution digital video. The wake behind a swimming eel in the horizontal midline plane is described first. Rather than producing a wake with fluid jets angled backwards, like in fishes such as sunfish, eels have a wake with exclusively lateral jets. The lack of downstream momentum indicates that eels balance the axial forces of thrust and drag evenly over time and over their bodies, and therefore do not change axial fluid momentum. This even balance, present at all steady swimming speeds, is probably due to the relatively uniform body shape of eels. As eels accelerate, thrust exceeds drag, axial momentum increases, and the wake approaches that of other fishes. During steady swimming, though, the lack of axial momentum prevents direct efficiency estimation. The effect of body shape was examined directly by measuring flow in multiple transverse planes along the body of bluegill sunfish swimming at 1.2 L s-1. The dorsal and anal fin, neglected in many previous

  16. Genetics Home Reference: Floating-Harbor syndrome

    Science.gov (United States)

    ... Patton MA, Hurst J, Donnai D, McKeown CM, Cole T, Goodship J. Floating-Harbor syndrome. J Med ... medicine? What is newborn screening? New Pages Lyme disease Fibromyalgia White-Sutton syndrome All New & Updated Pages ...

  17. Madaket Harbor, Nantucket, Massachusetts. Water Resources Improvement.

    Science.gov (United States)

    1977-07-01

    will continue to be, important increases in the recreational use of land and water. The harbor area is an important arena for commercial shellfishing...an important arena for commercial shell fishing. The past few years have seen a rather rapid increase in residential land use. Construction has...beamc. Tnis material will be re-deposited,, viaj troio it 1-apfro1inr ox prior location. j, MADAKET HARBOR NANTUCKET, MASSACHUSETTS FEASIBILITY

  18. Sex differences associated with intermittent swim stress.

    Science.gov (United States)

    Warner, Timothy A; Libman, Matthew K; Wooten, Katherine L; Drugan, Robert C

    2013-11-01

    Various animal models of depression have been used to seek a greater understanding of stress-related disorders. However, there is still a great need for novel research in this area, as many individuals suffering from depression are resistant to current treatment methods. Women have a higher rate of depression, highlighting the need to investigate mechanisms of sex differences. Therefore, we employed a new animal model to assess symptoms of depression, known as intermittent swim stress (ISS). In this model, the animal experiences 100 trials of cold water swim stress. ISS has already been shown to cause signs of behavioral depression in males, but has yet to be assessed in females. Following ISS exposure, we looked at sex differences in the Morris water maze and forced swim test. The results indicated a spatial learning effect only in the hidden platform task between male and female controls, and stressed and control males. A consistent spatial memory effect was only seen for males exposed to ISS. In the forced swim test, both sexes exposed to ISS exhibited greater immobility, and the same males and females also showed attenuated climbing and swimming, respectively. The sex differences could be due to different neural substrates for males and females. The goal of this study was to provide the first behavioral examination of sex differences following ISS exposure, so the stage of estrous cycle was not assessed for the females. This is a necessary future direction for subsequent experiments. The current article highlights the importance of sex differences in response to stress.

  19. Fish Swimming and Bird/Insect Flight

    Science.gov (United States)

    Wu, Theodore Yaotsu

    2011-01-01

    This expository review is devoted to fish swimming and bird/insect flight. (a) The simple waving motion of an elongated flexible ribbon plate of constant width propagating a wave distally down the plate to swim forward in a fluid, initially at rest, is first considered to provide a fundamental concept on energy conservation. It is generalized to include variations in body width and thickness, with appended dorsal, ventral and caudal fins shedding vortices to closely simulate fish swimming, for which a nonlinear theory is presented for large-amplitude propulsion. (b) For bird flight, the pioneering studies on oscillatory rigid wings are discussed with delineating a fully nonlinear unsteady theory for a two-dimensional flexible wing with arbitrary variations in shape and trajectory to provide a comparative study with experiments. (c) For insect flight, recent advances are reviewed by items on aerodynamic theory and modeling, computational methods, and experiments, for forward and hovering flights with producing leading-edge vortex to yield unsteady high lift. (d) Prospects are explored on extracting prevailing intrinsic flow energy by fish and bird to enhance thrust for propulsion. (e) The mechanical and biological principles are drawn together for unified studies on the energetics in deriving metabolic power for animal locomotion, leading to the surprising discovery that the hydrodynamic viscous drag on swimming fish is largely associated with laminar boundary layers, thus drawing valid and sound evidences for a resounding resolution to the long-standing fish-swim paradox proclaimed by Gray (1936, 1968 ).

  20. Research on Relative Age in Hungarian Swimming

    Directory of Open Access Journals (Sweden)

    Nagy Nikoletta

    2015-12-01

    Full Text Available In 2017, the 19th World Swimming Championship will be organized in Hungary. Up to now, many people have already been working with swimmers to achieve good results. However, in the next period they must work even harder to ensure that the national swimmers of a country as small as Hungary can achieve the outstanding results of their predecessors. Since high-level competitions in swimming have become more intense, innovations including scientific studies are needed during preparation for the event. The purpose of this paper is to present the major results of an independent study carried out by the authors about the relative age of the best Hungarian swimmers with the aim of contributing to their preparation. The research population consisted of selected age groups of swimmers registered by the Hungarian Swimming Association (N=400. The method for data collection was an analysis of documents. To evaluate the data, the Chi-square and Kruskal-Wallis tests were used. The results are presented according to the period of the competitor’s date of birth, gender, and age group. The results confirm only partly the hypothesis that people born in the first quarters of the year play a dominant role in Hungarian national swimming teams. In the conclusion, the authors recommend further research on relative age in swimming and in other sports.

  1. Quiet swimming at low Reynolds number

    DEFF Research Database (Denmark)

    Andersen, Anders Peter; Wadhwa, Navish; Kiørboe, Thomas

    2015-01-01

    The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that elim......The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode...... that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturbance described by a force quadrupole that decays as one over distance cubed. Motivated by recent experimental results on fluid disturbances due to small aquatic organisms, we demonstrate that a three......-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws...

  2. SWIMMING BEHAVIOR OF DEVELOPMENTAL STAGES OF THE CALANOID COPEPOD TEMORA-LONGICORNIS AT DIFFERENT FOOD CONCENTRATIONS

    NARCIS (Netherlands)

    VANDUREN, LA; VIDELER, JJ

    1995-01-01

    The swimming behaviour of developmental stages of the marine calanoid copepod Temora longicornis was studied using 2-dimensional observations under a microscope and a 3-dimensional filming technique to analyze swimming mode, swimming speed and swimming trajectories under different food

  3. Recreational Boat Harbor, Cedar River, Michigan. Revisions to General Design Memorandum Number 1 and Environmental Impact Statement. Supplement Number 1.

    Science.gov (United States)

    1980-08-01

    26, Tuesday, February 6, 1979. 16. Personal communication with Jim Harter, J.W. Wells State Park Director. 17. Fassett, N.C.; A Manual of Acuatic ...Harbor, Cedar River, Michigan. Pgs. G-37 - q-54. i~ A- A measure of a .h- calact’ a tion to neutrajz hrc-ge, .ons navinc a p. of more than 7. Acuatic ...and ship navigation. Navi- gation aids are often placed on the outermost end of Corps breakwaters and piers. Nekton - Swimming aquatic insects and fish

  4. Analysis of swimming performance: perceptions and practices of US-based swimming coaches.

    Science.gov (United States)

    Mooney, Robert; Corley, Gavin; Godfrey, Alan; Osborough, Conor; Newell, John; Quinlan, Leo Richard; ÓLaighin, Gearóid

    2016-01-01

    In elite swimming, a broad range of methods are used to assess performance, inform coaching practices and monitor athletic progression. The aim of this paper was to examine the performance analysis practices of swimming coaches and to explore the reasons behind the decisions that coaches take when analysing performance. Survey data were analysed from 298 Level 3 competitive swimming coaches (245 male, 53 female) based in the United States. Results were compiled to provide a generalised picture of practices and perceptions and to examine key emerging themes. It was found that a disparity exists between the importance swim coaches place on biomechanical analysis of swimming performance and the types of analyses that are actually conducted. Video-based methods are most frequently employed, with over 70% of coaches using these methods at least monthly, with analyses being mainly qualitative in nature rather than quantitative. Barriers to the more widespread use of quantitative biomechanical analysis in elite swimming environments were explored. Constraints include time, cost and availability of resources, but other factors such as sources of information on swimming performance and analysis and control over service provision are also discussed, with particular emphasis on video-based methods and emerging sensor-based technologies.

  5. Propulsive efficiency of frog swimming with different feet and swimming patterns

    Directory of Open Access Journals (Sweden)

    Fan Jizhuang

    2017-04-01

    Full Text Available Aquatic and terrestrial animals have different swimming performances and mechanical efficiencies based on their different swimming methods. To explore propulsion in swimming frogs, this study calculated mechanical efficiencies based on data describing aquatic and terrestrial webbed-foot shapes and swimming patterns. First, a simplified frog model and dynamic equation were established, and hydrodynamic forces on the foot were computed according to computational fluid dynamic calculations. Then, a two-link mechanism was used to stand in for the diverse and complicated hind legs found in different frog species, in order to simplify the input work calculation. Joint torques were derived based on the virtual work principle to compute the efficiency of foot propulsion. Finally, two feet and swimming patterns were combined to compute propulsive efficiency. The aquatic frog demonstrated a propulsive efficiency (43.11% between those of drag-based and lift-based propulsions, while the terrestrial frog efficiency (29.58% fell within the range of drag-based propulsion. The results illustrate the main factor of swimming patterns for swimming performance and efficiency.

  6. Is swimming during pregnancy a safe exercise?

    DEFF Research Database (Denmark)

    Juhl, Mette; Kogevinas, Manolis; Andersen, Per Kragh

    2010-01-01

    ,486 singleton pregnancies. Recruitment to The Danish National Birth Cohort took place 1996-2002. Using Cox, linear and logistic regression analyses, depending on the outcome, we compared swimmers with physically inactive pregnant women; to separate a possible swimming effect from an effect of exercise......BACKGROUND: Exercise in pregnancy is recommended in many countries, and swimming is considered by many to be an ideal activity for pregnant women. Disinfection by-products in swimming pool water may, however, be associated with adverse effects on various reproductive outcomes. We examined......, bicyclists were included as an additional comparison group. RESULTS: Risk estimates were similar for swimmers and bicyclists, including those who swam throughout pregnancy and those who swam more than 1.5 hours per week. Compared with nonexercisers, women who swam in early/mid-pregnancy had a slightly...

  7. Energetics of swimming of schooling fish

    DEFF Research Database (Denmark)

    Steffensen, John Fleng

    2012-01-01

    , i.e. nearest neighbour distance, water temperature, gill oxygen extraction, gill ventilation capacity, etc. Fish swimming in a school have been shown to have energetic advantages when trailing behind neighbours, resulting in up to 20% energy saving. The effect of this energy saving is that the fish......Soc for experimental Biol Annual Meeting - Salzburg 2012 John F. Steffensen (University of Copenhagen, Denmark) When a fish school swims through the water, every individual consumes a certain amount of oxygen, which means that less will be available for the trailing fish in the school. In 1967 Mc......Farland and Moss reported that the oxygen saturation decreased approximately 30% from the front to the rear of an approximately 150-m long school of mullets swimming in normoxic water. They also observed that the decline in oxygen saturation at the rear resulted in the school disintegrating into smaller separate...

  8. Determinant kinantropometric factors in swimming

    Directory of Open Access Journals (Sweden)

    João Paulo Vilas-Boas

    2002-12-01

    Full Text Available The aim of this work is to present a bibliographic review, based on the specialized literature, of the kineantropometric characteristics of swimmers and their importance for swimming performance. The main conclusions were: (i swimmers are taller and heavier than the general population; (ii swimmers present an high index of arm span/height (explained by a large biacromial diameter and long the upper arm; (iii high values for the biacromial/bicristal diameter ratio were found, offering a lower drag coeffi cient; (iv high length and surface area arm and leg values were observed (which positively infl uence their propulsion capacity; (v elite male swimmers presents a ectomorph-endomorph somatotype and elite female swimmers are central or balanced mesomorphs (vi swimmers exhibit a higher percentage of body mass than other athletes, which may benefi t positively their floatation. RESUMO O objetivo deste trabalho é apresentar uma revisão bibliográfi ca das principais características cineantropométricas do nadador e a forma como estas infl uenciam a sua prestação na modalidade. As principais conclusões obtidas foram as seguintes: (i os nadadores são mais altos e pesados do que a população em geral; (ii os nadadores apresentam um elevado índice envergadura/ altura, explicitando valores elevados do diâmetro biacromial e do comprimento dos MS; (iii verifi ca-se uma elevada razão entre os diâmetros biacromial e bicristal, traduzindo um fator decisivo na modalidade: a promoção de um coefi ciente de arrasto inferior; (iv foram observados elevados valores de comprimento e superfície dos membros dos nadadores (afetando positivamente a sua capacidade propulsiva; (v os nadadores de elite apresentam um somatótipo médio ecto-mesomorfo e as nadadoras são centrais ou mesomorfas equilibradas; (vi como grupo, os nadadores apresentam um maior percentual de massa gorda do que outros desportistas, fator este que poderá beneficiálos relativamente

  9. Infections Unlikely to be Spread Through Swimming Pools

    Science.gov (United States)

    ... Water Home Infections Unlikely to be Spread Through Swimming Pools Language: English (US) Español (Spanish) Recommend on ... included below. Infections Unlikely to be Spread by Swimming Pools Head Lice Head lice are unlikely to ...

  10. Estimating energy expenditure during front crawl swimming using accelerometers

    DEFF Research Database (Denmark)

    Nordsborg, Nikolai Baastrup; Espinosa, Hugo G.; Van Thiel, David H

    2014-01-01

    The determination of energy expenditure is of major interest in training load and performance assessment. Small, wireless accelerometer units have the potential to characterise energy expenditure during swimming. The correlation between absorbed oxygen versus flume swimming speed and absorbed oxy...

  11. Front crawl swimming analysis using accelerometers

    DEFF Research Database (Denmark)

    Espinosa, Hugo G; Nordsborg, Nikolai Baastrup; Thiel, David V

    2015-01-01

    Biomechanical characteristics such as stroke rate and stroke length can be used to determine the velocity of a swimmer and can be analysed in both a swimming pool and a flume. The aim of the present preliminary study was to investigate the differences between the acceleration data collected from...... a swimming pool with that collected from a flume, as a function of the swimmer's stroke rate and stroke count, with the objective of identifying the impact on the swimmer's performance. The differences were determined by the analysis of the stroke's features, comparing several strokes normalized to one...

  12. Paramecium swimming in a capillary tube

    Science.gov (United States)

    Jana, Saikat; Jung, Sunghwan

    2010-03-01

    Micro-organisms exhibit different strategies for swimming in complex environments. Many micro-swimmers such as paramecium congregate and tend to live near wall. We investigate how paramecium moves in a confined space as compared to its motion in an unbounded fluid. A new theoretical model based on Taylor's sheet is developed, to study such boundary effects. In experiments, paramecia are put inside capillary tubes and their swimming behavior is observed. The data obtained from experiments is used to test the validity of our theoretical model and understand how the cilia influence the locomotion of paramecia in confined geometries.

  13. 76 FR 8653 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor...

    Science.gov (United States)

    2011-02-15

    ... Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor Navigation Canal, New Orleans, Orleans Parish, LA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from... Lock), at New Orleans, Orleans Parish, Louisiana. This deviation is necessary to replace all of the...

  14. 75 FR 78601 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor...

    Science.gov (United States)

    2010-12-16

    ... Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor Navigation Canal, New Orleans, Orleans Parish, LA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from... Harvey Lock), at New Orleans, Orleans Parish, Louisiana. This deviation is necessary to adjust the...

  15. (Important hygienic aspects for swimming pools (author's transl))

    Energy Technology Data Exchange (ETDEWEB)

    Somosi, G

    1981-01-01

    The major epidemics which occurred in Hungary and originated from water in swimming pools are reported. The difficulties encountered in producing epidemiological evidence and in monitoring infections originating from water in swimming pools are mentioned. The possibilities of controlling the water quality in swimming pools and of preventing infections are discussed. Reference is made to the existing bacteriological limit values in Hungary to be observed in the recirculation of water in swimming pools.

  16. 76 FR 60732 - Drawbridge Operation Regulations; Navesink (Swimming) River, NJ

    Science.gov (United States)

    2011-09-30

    ... Operation Regulations; Navesink (Swimming) River, NJ AGENCY: Coast Guard, DHS. ACTION: Notice of temporary... (Swimming) River between Oceanic and Locust Point, New Jersey. The deviation is necessary to facilitate...: The Oceanic Bridge, across the Navesink (Swimming) River, mile 4.5, between Oceanic and Locust Point...

  17. Do all frogs swim alike? The effect of ecological specialization on swimming kinematics in frogs

    Czech Academy of Sciences Publication Activity Database

    Robovská-Havelková, P.; Aerts, P.; Roček, Zbyněk; Přikryl, Tomáš; Fabre, A.-C.; Herrel, A.

    2014-01-01

    Roč. 217, č. 20 (2014), s. 3637-3644 ISSN 0022-0949 Institutional support: RVO:67985831 Keywords : Anura * kinematics * locomotion * swimming Subject RIV: EG - Zoology Impact factor: 2.897, year: 2014

  18. Biomechanics of swimming in developing larval fish

    NARCIS (Netherlands)

    Voesenek, Cees J.; Muijres, Florian T.; Leeuwen, Van Johan L.

    2018-01-01

    Most larvae of bony fish are able to swim almost immediately after hatching. Their locomotory system supports several vital functions: fish larvae make fast manoeuvres to escape from predators, aim accurately during suction feeding and maymigrate towards suitable future habitats. Owing to their

  19. Surveillance and Conformity in Competitive Youth Swimming

    Science.gov (United States)

    Lang, Melanie

    2010-01-01

    Underpinned by a Foucauldian analysis of sporting practices, this paper identifies the disciplinary mechanism of surveillance at work in competitive youth swimming. It highlights the ways in which swimmers and their coaches are subject to and apply this mechanism to produce embodied conformity to normative behaviour and obedient, docile bodies.…

  20. Healthy Swimming Is a Partnership Effort

    Science.gov (United States)

    Grosse, Susan J.

    2009-01-01

    While one cannot control the water chemistry, he/she can control personal hygiene and facility cleanliness. Giardia and cryptosporidium (crypto) are only two of the many recreational water illnesses (RWIs) that can turn happy swim memories into serious illness situations. In this article, the author discusses three factors that determine how…

  1. Swimming-pool piles; Piles piscines

    Energy Technology Data Exchange (ETDEWEB)

    Trioulaire, M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10{sup 13}. This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [French] En France, deux piles piscines, Melusine et Triton, viennent d'entrer en service. La pile piscine est l'outil de recherche ideal pour des flux de neutrons de l'ordre de 10{sup 13}. Ce type de pile peut interesser des maintenant de nombreux centres de recherches mais il faut reduire son prix de revient et rompre avec le conformisme de sa conception. Il y a avantage: - a enterrer la piscine; - a supprimer les canaux experimentaux; - a concentrer le circuit de refrigeration dans la piscine; - a effectuer toutes les manipulations dans l'eau; - a doubler le coeur. (auteur)

  2. Swimming in air-breathing fishes.

    Science.gov (United States)

    Lefevre, S; Domenici, P; McKenzie, D J

    2014-03-01

    Fishes with bimodal respiration differ in the extent of their reliance on air breathing to support aerobic metabolism, which is reflected in their lifestyles and ecologies. Many freshwater species undertake seasonal and reproductive migrations that presumably involve sustained aerobic exercise. In the six species studied to date, aerobic exercise in swim flumes stimulated air-breathing behaviour, and there is evidence that surfacing frequency and oxygen uptake from air show an exponential increase with increasing swimming speed. In some species, this was associated with an increase in the proportion of aerobic metabolism met by aerial respiration, while in others the proportion remained relatively constant. The ecological significance of anaerobic swimming activities, such as sprinting and fast-start manoeuvres during predator-prey interactions, has been little studied in air-breathing fishes. Some species practise air breathing during recovery itself, while others prefer to increase aquatic respiration, possibly to promote branchial ion exchange to restore acid-base balance, and to remain quiescent and avoid being visible to predators. Overall, the diversity of air-breathing fishes is reflected in their swimming physiology as well, and further research is needed to increase the understanding of the differences and the mechanisms through which air breathing is controlled and used during exercise. © 2014 The Fisheries Society of the British Isles.

  3. Locomotor activity during the frenzy swim: analysing early swimming behaviour in hatchling sea turtles.

    Science.gov (United States)

    Pereira, Carla M; Booth, David T; Limpus, Colin J

    2011-12-01

    Swimming effort of hatchling sea turtles varies across species. In this study we analysed how swim thrust is produced in terms of power stroke rate, mean maximum thrust per power stroke and percentage of time spent power stroking throughout the first 18 h of swimming after entering the water, in both loggerhead and flatback turtle hatchlings and compared this with previous data from green turtle hatchlings. Loggerhead and green turtle hatchlings had similar power stroke rates and percentage of time spent power stroking throughout the trial, although mean maximum thrust was always significantly higher in green hatchlings, making them the most vigorous swimmers in our three-species comparison. Flatback hatchlings, however, were different from the other two species, with overall lower values in all three swimming variables. Their swimming effort dropped significantly during the first 2 h and kept decreasing significantly until the end of the trial at 18 h. These results support the hypothesis that ecological factors mould the swimming behaviour of hatchling sea turtles, with predator pressure being important in determining the strategy used to swim offshore. Loggerhead and green turtle hatchlings seem to adopt an intensely vigorous and energetically costly frenzy swim that would quickly take them offshore into the open ocean in order to reduce their exposure to near-shore aquatic predators. Flatback hatchlings, however, are restricted in geographic distribution and remain within the continental shelf region where predator pressure is probably relatively constant. For this reason, flatback hatchlings might use only part of their energy reserves during a less vigorous frenzy phase, with lower overall energy expenditure during the first day compared with loggerhead and green turtle hatchlings.

  4. Kick, Stroke and Swim: Complement Your Swimming Program by Engaging the Whole Body on Dry Land and in the Pool

    Science.gov (United States)

    Flynn, Susan; Duell, Kelly; Dehaven, Carole; Heidorn, Brent

    2017-01-01

    The Kick, Stroke and Swim (KSS) program can be used to engage students in swimming-skill acquisition and fitness training using a variety of modalities, strategies and techniques on dry land. Practicing swim strokes and techniques on land gives all levels of swimmers--from beginner to competitive--a kinesthetic awareness of the individual…

  5. New Harbor in Kangerlussuaq, Western Greenland

    DEFF Research Database (Denmark)

    Stenstad, Jaran Gjerlandj; Eppeland, Kjetil Grødal; Ingeman-Nielsen, Thomas

    2015-01-01

    transported by rivers from the inland ice to the inner parts of the fjord. These sediment layers reduce the water depth and prevent container- and cruiseships to dock, imposing large additional maintenance costs, and inefficient operability. Through engineering geological field and lab investigations......, a possible new harbor location around 10 km further out the fjord near Hancock Pynt, has been investigated. The onshore area was found to be highly suitable for a harbor support area, where a sub-base thickness of 1.8 m with gravel cover-layer was found adequate for the calculated design loads. Existing...

  6. Unsteady propulsion by an intermittent swimming gait

    Science.gov (United States)

    Akoz, Emre; Moored, Keith W.

    2018-01-01

    Inviscid computational results are presented on a self-propelled swimmer modeled as a virtual body combined with a two-dimensional hydrofoil pitching intermittently about its leading edge. Lighthill (1971) originally proposed that this burst-and-coast behavior can save fish energy during swimming by taking advantage of the viscous Bone-Lighthill boundary layer thinning mechanism. Here, an additional inviscid Garrick mechanism is discovered that allows swimmers to control the ratio of their added mass thrust-producing forces to their circulatory drag-inducing forces by decreasing their duty cycle, DC, of locomotion. This mechanism can save intermittent swimmers as much as 60% of the energy it takes to swim continuously at the same speed. The inviscid energy savings are shown to increase with increasing amplitude of motion, increase with decreasing Lighthill number, Li, and switch to an energetic cost above continuous swimming for sufficiently low DC. Intermittent swimmers are observed to shed four vortices per cycle that form into groups that are self-similar with the DC. In addition, previous thrust and power scaling laws of continuous self-propelled swimming are further generalized to include intermittent swimming. The key is that by averaging the thrust and power coefficients over only the bursting period then the intermittent problem can be transformed into a continuous one. Furthermore, the intermittent thrust and power scaling relations are extended to predict the mean speed and cost of transport of swimmers. By tuning a few coefficients with a handful of simulations these self-propelled relations can become predictive. In the current study, the mean speed and cost of transport are predicted to within 3% and 18% of their full-scale values by using these relations.

  7. Pacing in Swimming: A Systematic Review.

    Science.gov (United States)

    McGibbon, Katie E; Pyne, D B; Shephard, M E; Thompson, K G

    2018-03-20

    Pacing strategy, or how energy is distributed during exercise, can substantially impact athletic performance and is considered crucial for optimal performance in many sports. This is particularly true in swimming given the highly resistive properties of water and low mechanical efficiency of the swimming action. The aim of this systematic review was to determine the pacing strategies utilised by competitive swimmers in competition and their reproducibility, and to examine the impact of different pacing strategies on kinematic, metabolic and performance variables. This will provide valuable and practical information to coaches and sports science practitioners. The databases Web of Science, Scopus, SPORTDiscus and PubMed were searched for published articles up to 1 August 2017. A total of 23 studies examining pool-based swimming competitions or experimental trials in English-language and peer-reviewed journals were included in this review. In short- and middle-distance swimming events maintenance of swimming velocity is critical, whereas in long-distance events a low lap-to-lap variability and the ability to produce an end spurt in the final lap(s) are key. The most effective strategy in the individual medley (IM) is to conserve energy during the butterfly leg to optimise performance in subsequent legs. The pacing profiles of senior swimmers remain relatively stable irrespective of opponents, competition stage or type, and performance time. Implementing event-specific pacing strategies should benefit the performance of competitive swimmers. Given differences between swimmers, there is a need for greater individualisation when considering pacing strategy selection across distances and strokes.

  8. SWIM (Soil and Water Integrated Model)

    Energy Technology Data Exchange (ETDEWEB)

    Krysanova, V; Wechsung, F; Arnold, J; Srinivasan, R; Williams, J

    2000-12-01

    The model SWIM (Soil and Water Integrated Model) was developed in order to provide a comprehensive GIS-based tool for hydrological and water quality modelling in mesoscale and large river basins (from 100 to 10,000 km{sup 2}), which can be parameterised using regionally available information. The model was developed for the use mainly in Europe and temperate zone, though its application in other regions is possible as well. SWIM is based on two previously developed tools - SWAT and MATSALU (see more explanations in section 1.1). The model integrates hydrology, vegetation, erosion, and nutrient dynamics at the watershed scale. SWIM has a three-level disaggregation scheme 'basin - sub-basins - hydrotopes' and is coupled to the Geographic Information System GRASS (GRASS, 1993). A robust approach is suggested for the nitrogen and phosphorus modelling in mesoscale watersheds. SWIM runs under the UNIX environment. Model test and validation were performed sequentially for hydrology, crop growth, nitrogen and erosion in a number of mesoscale watersheds in the German part of the Elbe drainage basin. A comprehensive scheme of spatial disaggregation into sub-basins and hydrotopes combined with reasonable restriction on a sub-basin area allows performing the assessment of water resources and water quality with SWIM in mesoscale river basins. The modest data requirements represent an important advantage of the model. Direct connection to land use and climate data provides a possibility to use the model for analysis of climate change and land use change impacts on hydrology, agricultural production, and water quality. (orig.)

  9. Optimal swimming strategies in mate searching pelagic copepods

    DEFF Research Database (Denmark)

    Kiørboe, Thomas

    2008-01-01

    Male copepods must swim to find females, but swimming increases the risk of meeting predators and is expensive in terms of energy expenditure. Here I address the trade-offs between gains and risks and the question of how much and how fast to swim using simple models that optimise the number...... of lifetime mate encounters. Radically different swimming strategies are predicted for different feeding behaviours, and these predictions are tested experimentally using representative species. In general, male swimming speeds and the difference in swimming speeds between the genders are predicted...... and observed to increase with increasing conflict between mate searching and feeding. It is high in ambush feeders, where searching (swimming) and feeding are mutually exclusive and low in species, where the matured males do not feed at all. Ambush feeding males alternate between stationary ambush feeding...

  10. Evaluation of Sediment Contamination in Pearl Harbor

    Science.gov (United States)

    1992-06-01

    ancient Hawaiians, was a large natural inland lagoon. Numerous walled fishponds located inside the harbor were used to cultivate various species of fishes... Ecotoxicology , Commission on Natural Resources, National Academy Press, Washington, D.C., 103 pp. National Research Council, 1989. Contaminated Marine

  11. The evolution of phenotypic plasticity in fish swimming

    Science.gov (United States)

    Oufiero, Christopher E.; Whitlow, Katrina R.

    2016-01-01

    Abstract Fish have a remarkable amount of variation in their swimming performance, from within species differences to diversity among major taxonomic groups. Fish swimming is a complex, integrative phenotype and has the ability to plastically respond to a myriad of environmental changes. The plasticity of fish swimming has been observed on whole-organismal traits such as burst speed or critical swimming speed, as well as underlying phenotypes such as muscle fiber types, kinematics, cardiovascular system, and neuronal processes. Whether the plastic responses of fish swimming are beneficial seems to depend on the environmental variable that is changing. For example, because of the effects of temperature on biochemical processes, alterations of fish swimming in response to temperature do not seem to be beneficial. In contrast, changes in fish swimming in response to variation in flow may benefit the fish to maintain position in the water column. In this paper, we examine how this plasticity in fish swimming might evolve, focusing on environmental variables that have received the most attention: temperature, habitat, dissolved oxygen, and carbon dioxide variation. Using examples from previous research, we highlight many of the ways fish swimming can plastically respond to environmental variation and discuss potential avenues of future research aimed at understanding how plasticity of fish swimming might evolve. We consider the direct and indirect effects of environmental variation on swimming performance, including changes in swimming kinematics and suborganismal traits thought to predict swimming performance. We also discuss the role of the evolution of plasticity in shaping macroevolutionary patterns of diversity in fish swimming. PMID:29491937

  12. A Correlational Analysis of Tethered Swimming, Swim Sprint Performance and Dry-land Power Assessments.

    Science.gov (United States)

    Loturco, I; Barbosa, A C; Nocentini, R K; Pereira, L A; Kobal, R; Kitamura, K; Abad, C C C; Figueiredo, P; Nakamura, F Y

    2016-03-01

    Swimmers are often tested on both dry-land and in swimming exercises. The aim of this study was to test the relationships between dry-land, tethered force-time curve parameters and swimming performances in distances up to 200 m. 10 young male high-level swimmers were assessed using the maximal isometric bench-press and quarter-squat, mean propulsive power in jump-squat, squat and countermovement jumps (dry-land assessments), peak force, average force, rate of force development (RFD) and impulse (tethered swimming) and swimming times. Pearson product-moment correlations were calculated among the variables. Peak force and average force were very largely correlated with the 50- and 100-m swimming performances (r=- 0.82 and -0.74, respectively). Average force was very-largely/largely correlated with the 50- and 100-m performances (r=- 0.85 and -0.67, respectively). RFD and impulse were very-largely correlated with the 50-m time (r=- 0.72 and -0.76, respectively). Tethered swimming parameters were largely correlated (r=0.65 to 0.72) with mean propulsive power in jump-squat, squat-jump and countermovement jumps. Finally, mean propulsive power in jump-squat was largely correlated (r=- 0.70) with 50-m performance. Due to the significant correlations between dry-land assessments and tethered/actual swimming, coaches are encouraged to implement strategies able to increase leg power in sprint swimmers. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Effects of intraspecific variation in reproductive traits, pectoral fin use and burst swimming on metabolic rates and swimming performance in the Trinidadian guppy (Poecilia reticulata)

    DEFF Research Database (Denmark)

    Svendsen, Jon Christian; Banet, Amanda I.; Christensen, Rune Haubo Bojesen

    2013-01-01

    by the total body mass. Results showed that the metabolic rate increased curvilinearly with swimming speed. The slope of the relationship was used as an index of swimming cost. There was no evidence that reproductive traits correlated with swimming cost, MO2std or Ucrit. In contrast, data revealed strong...... swimming and pectoral fin movement over a wide speed range, presumably to support swimming stability and control, is an inefficient swimming behaviour. Finally, transition to burst-assisted swimming was associated with an increase in aerobic metabolic rate. Our study highlights factors other than swimming...

  14. Modeling of Tsunami Currents in Harbors

    Science.gov (United States)

    Lynett, P. J.

    2010-12-01

    Extreme events, such as large wind waves and tsunamis, are well recognized as a damaging hazard to port and harbor facilities. Wind wave events, particularly those with long period spectral components or infragravity wave generation, can excite resonance inside harbors leading to both large vertical motions and strong currents. Tsunamis can cause great damage as well. The geometric amplification of these very long waves can create large vertical motions in the interior of a harbor. Additionally, if the tsunami is composed of a train of long waves, which it often is, resonance can be easily excited. These long wave motions create strong currents near the node locations of resonant motions, and when interacting with harbor structures such as breakwaters, can create intense turbulent rotational structures, typical in the form of large eddies or gyres. These gyres have tremendous transport potential, and have been observed to break mooring lines, and even cause ships to be trapped inside the rotation, moving helplessly with the flow until collision, grounding, or dissipation of the eddy (e.g. Okal et al., 2006). This presentation will introduce the traditional theory used to predict wave impacts on harbors, discussing both how these models are practically useful and in what types of situations require a more accurate tool. State-of-the-art numerical models will be introduced, with a focus on recent developments in Boussinesq-type modeling. The Boussinesq equations model can account the dispersive, turbulent and rotational flow properties frequently observed in nature. Also they have the ability to coupling currents and waves and can predict nonlinear wave propagation over uneven bottom from deep (or intermediate) water area to shallow water area. However, during the derivation of a 2D-horizontal equation set, some 3D flow features, such those driven by as the dispersive stresses and the effects of the unresolved small scale 3D turbulence, are excluded. Consequently

  15. Strategies for chemically healthy public swimming pools

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht

    spreading of pathogens between swimmers because of its residual disinfection effect. In addition to potential contamination of pathogenic microorganisms, swimming pool water is polluted by organic matter deposited from the bathers such as saliva, urine, sweat, hair and personal care products. Since chlorine...... is a strong oxidant it oxidizes the organic matter in the pool water and forms disinfection byproducts (DBPs). More than 100 different DBPs have been identified. Some of these have been found to be genotoxic and may pose an increased cancer risk for the bathers. The aim of this thesis was to give an overview...... of the strategies which can be used to achieve microbiological safe water with low levels of DBPs to ensure healthy environment for bathers. There are different approaches to achieve healthy environment in public swimming pools which in this thesis are divided into three strategies: alternatives to chlorination...

  16. Swimming versus swinging effects in spacetime

    International Nuclear Information System (INIS)

    Gueron, Eduardo; Maia, Clovis A. S.; Matsas, George E. A.

    2006-01-01

    Wisdom has recently unveiled a new relativistic effect, called 'spacetime swimming', where quasirigid free bodies in curved spacetimes can 'speed up', 'slow down' or 'deviate' their falls by performing local cyclic shape deformations. We show here that for fast enough cycles this effect dominates over a nonrelativistic related one, named here 'space swinging', where the fall is altered through nonlocal cyclic deformations in Newtonian gravitational fields. We expect, therefore, to clarify the distinction between both effects leaving no room to controversy. Moreover, the leading contribution to the swimming effect predicted by Wisdom is enriched with a higher order term and the whole result is generalized to be applicable in cases where the tripod is in large redshift regions

  17. Swimming Dynamics of the Lyme Disease Spirochete

    Science.gov (United States)

    Vig, Dhruv K.; Wolgemuth, Charles W.

    2012-11-01

    The Lyme disease spirochete, Borrelia burgdorferi, swims by undulating its cell body in the form of a traveling flat wave, a process driven by rotating internal flagella. We study B. burgdorferi’s swimming by treating the cell body and flagella as linearly elastic filaments. The dynamics of the cell are then determined from the balance between elastic and resistive forces and moments. We find that planar, traveling waves only exist when the flagella are effectively anchored at both ends of the bacterium and that these traveling flat waves rotate as they undulate. The model predicts how the undulation frequency is related to the torque from the flagellar motors and how the stiffness of the cell body and flagella affect the undulations and morphology.

  18. Comparative jet wake structure and swimming performance of salps.

    Science.gov (United States)

    Sutherland, Kelly R; Madin, Laurence P

    2010-09-01

    Salps are barrel-shaped marine invertebrates that swim by jet propulsion. Morphological variations among species and life-cycle stages are accompanied by differences in swimming mode. The goal of this investigation was to compare propulsive jet wakes and swimming performance variables among morphologically distinct salp species (Pegea confoederata, Weelia (Salpa) cylindrica, Cyclosalpa sp.) and relate swimming patterns to ecological function. Using a combination of in situ dye visualization and particle image velocimetry (PIV) measurements, we describe properties of the jet wake and swimming performance variables including thrust, drag and propulsive efficiency. Locomotion by all species investigated was achieved via vortex ring propulsion. The slow-swimming P. confoederata produced the highest weight-specific thrust (T=53 N kg(-1)) and swam with the highest whole-cycle propulsive efficiency (eta(wc)=55%). The fast-swimming W. cylindrica had the most streamlined body shape but produced an intermediate weight-specific thrust (T=30 N kg(-1)) and swam with an intermediate whole-cycle propulsive efficiency (eta(wc)=52%). Weak swimming performance variables in the slow-swimming C. affinis, including the lowest weight-specific thrust (T=25 N kg(-1)) and lowest whole-cycle propulsive efficiency (eta(wc)=47%), may be compensated by low energetic requirements. Swimming performance variables are considered in the context of ecological roles and evolutionary relationships.

  19. Controlled-frequency breath swimming improves swimming performance and running economy.

    Science.gov (United States)

    Lavin, K M; Guenette, J A; Smoliga, J M; Zavorsky, G S

    2015-02-01

    Respiratory muscle fatigue can negatively impact athletic performance, but swimming has beneficial effects on the respiratory system and may reduce susceptibility to fatigue. Limiting breath frequency during swimming further stresses the respiratory system through hypercapnia and mechanical loading and may lead to appreciable improvements in respiratory muscle strength. This study assessed the effects of controlled-frequency breath (CFB) swimming on pulmonary function. Eighteen subjects (10 men), average (standard deviation) age 25 (6) years, body mass index 24.4 (3.7) kg/m(2), underwent baseline testing to assess pulmonary function, running economy, aerobic capacity, and swimming performance. Subjects were then randomized to either CFB or stroke-matched (SM) condition. Subjects completed 12 training sessions, in which CFB subjects took two breaths per length and SM subjects took seven. Post-training, maximum expiratory pressure improved by 11% (15) for all 18 subjects (P swimming may improve muscular oxygen utilization during terrestrial exercise in novice swimmers. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Quality Versus Quantity Debate in Swimming: Perceptions and Training Practices of Expert Swimming Coaches

    Directory of Open Access Journals (Sweden)

    Nugent Frank J.

    2017-06-01

    Full Text Available The debate over low-volume, high-intensity training versus high-volume, low-intensity training, commonly known as Quality versus Quantity, respectively, is a frequent topic of discussion among swimming coaches and academics. The aim of this study was to explore expert coaches’ perceptions of quality and quantity coaching philosophies in competitive swimming and to investigate their current training practices. A purposeful sample of 11 expert swimming coaches was recruited for this study. The study was a mixed methods design and involved each coach participating in 1 semi-structured interview and completing 1 closed-ended questionnaire. The main findings of this study were that coaches felt quality training programmes would lead to short term results for youth swimmers, but were in many cases more appropriate for senior swimmers. The coaches suggested that quantity training programmes built an aerobic base for youth swimmers, promoted technical development through a focus on slower swimming and helped to enhance recovery from training or competition. However, the coaches continuously suggested that quantity training programmes must be performed with good technique and they felt this was a misunderstood element. This study was a critical step towards gaining a richer and broader understanding on the debate over Quality versus Quantity training from an expert swimming coaches’ perspective which was not currently available in the research literature.

  1. Quality versus Quantity Debate in Swimming: Perceptions and Training Practices of Expert Swimming Coaches.

    Science.gov (United States)

    Nugent, Frank J; Comyns, Thomas M; Warrington, Giles D

    2017-06-01

    The debate over low-volume, high-intensity training versus high-volume, low-intensity training, commonly known as Quality versus Quantity, respectively, is a frequent topic of discussion among swimming coaches and academics. The aim of this study was to explore expert coaches' perceptions of quality and quantity coaching philosophies in competitive swimming and to investigate their current training practices. A purposeful sample of 11 expert swimming coaches was recruited for this study. The study was a mixed methods design and involved each coach participating in 1 semi-structured interview and completing 1 closed-ended questionnaire. The main findings of this study were that coaches felt quality training programmes would lead to short term results for youth swimmers, but were in many cases more appropriate for senior swimmers. The coaches suggested that quantity training programmes built an aerobic base for youth swimmers, promoted technical development through a focus on slower swimming and helped to enhance recovery from training or competition. However, the coaches continuously suggested that quantity training programmes must be performed with good technique and they felt this was a misunderstood element. This study was a critical step towards gaining a richer and broader understanding on the debate over Quality versus Quantity training from an expert swimming coaches' perspective which was not currently available in the research literature.

  2. Intra-abdominal pressure during swimming.

    Science.gov (United States)

    Moriyama, S; Ogita, F; Huang, Z; Kurobe, K; Nagira, A; Tanaka, T; Takahashi, H; Hirano, Y

    2014-02-01

    The present study aimed to determine the intra-abdominal pressure during front crawl swimming at different velocities in competitive swimmers and to clarify the relationships between stroke indices and changes in intra-abdominal pressure. The subjects were 7 highly trained competitive collegiate male swimmers. Intra-abdominal pressure was measured during front crawl swimming at 1.0, 1.2 and 1.4 m · s(-1) and during the Valsalva maneuver. Intra-abdominal pressure was taken as the difference between minimum and maximum values, and the mean of 6 stable front crawl stroke cycles was used. Stroke rate and stroke length were also measured as stroke indices. There were significant differences in stroke rate among all velocities (P pressure and stroke rate or stroke length (P pressure and stroke indices when controlling for swimming velocity. These findings do not appear to support the effectiveness of trunk training performed by competitive swimmers aimed at increasing intra-abdominal pressure. © Georg Thieme Verlag KG Stuttgart · New York.

  3. The swimming of a perfect deforming helix

    Science.gov (United States)

    Koens, Lyndon; Zhang, Hang; Mourran, Ahmed; Lauga, Eric

    2017-11-01

    Many bacteria rotate helical flagellar filaments in order to swim. When at rest or rotated counter-clockwise these flagella are left handed helices but they undergo polymorphic transformations to right-handed helices when the motor is reversed. These helical deformations themselves can generate motion, with for example Rhodobacter sphaeroides using the polymorphic transformation of the flagellum to generate rotation, or Spiroplasma propagating a change of helix handedness across its body's length to generate forward motion. Recent experiments reported on an artificial helical microswimmer generating motion without a propagating change in handedness. Made of a temperature sensitive gel, these swimmers moved by changing the dimensions of the helix in a non-reciprocal way. Inspired by these results and helix's ubiquitous presence in the bacterial world, we investigate how a deforming helix moves within a viscous fluid. Maintaining a single handedness along its entire length, we discuss how a perfect deforming helix can create a non-reciprocal swimming stroke, identify its principle directions of motion, and calculate the swimming kinematics asymptotically.

  4. Quiet swimming at low Reynolds number

    Science.gov (United States)

    Andersen, Anders; Wadhwa, Navish; Kiørboe, Thomas

    2015-04-01

    The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturbance described by a force quadrupole that decays as one over distance cubed. Motivated by recent experimental results on fluid disturbances due to small aquatic organisms, we demonstrate that a three-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws are valid surprisingly close to the organism. Finally, we discuss point force models as a general framework for hypothesis generation and experimental exploration of fluid mediated predator-prey interactions in the planktonic world.

  5. Desipramine restricts estral cycle oscillations in swimming.

    Science.gov (United States)

    Contreras, C M; Martínez-Mota, L; Saavedra, M

    1998-10-01

    1. Desipramine (DMI) is a tricyclic antidepressant which reduces the immobility in rats forced to swim; however, it is unknown whether estral cycle phases impinge on DMI actions on immobility in daily swimming tests during several weeks. 2. In female wistar rats, vaginal smears taken before testing defined four estral phases. Afterwards, the authors assessed the latency for the first period of immobility in five-min forced swim tests practiced on 21-day DMI (DMI group), 21-day washout saline given after a 21-day DMI treatment (washout-saline group), or non-treated rats (control group). 3. We observed a longer latency for the first period of immobility in proestrus-estrus from the control and washout-saline groups. The 21-day treatment with DMI (2.1 mg/kg i.p., once a day) significantly (p estral cycle phase. 4. It is concluded that proestrus-estrus relates to increased struggling behavior. DMI enhances struggling behavior independently of hormonal state.

  6. 32 CFR 765.6 - Regulations for Pearl Harbor, Hawaii.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Regulations for Pearl Harbor, Hawaii. 765.6... RULES RULES APPLICABLE TO THE PUBLIC § 765.6 Regulations for Pearl Harbor, Hawaii. The Commander, U.S. Naval Base, Pearl Harbor, Hawaii, is responsible for prescribing and enforcing such rules and...

  7. Teaching about Pearl Harbor. Curriculum Enhancement Series #1.

    Science.gov (United States)

    Shields, Anna Marshall

    These materials consist of sample lesson plans for teaching about the Japanese attack on Pearl Harbor on December 7, 1941, in both U.S. and world history classes. The lesson plans challenge students to examine how current attitudes toward the Japanese may be rooted in World War II and Pearl Harbor. Selected bibliographies on Pearl Harbor, World…

  8. Remembering Pearl Harbor at 75 Years.

    Science.gov (United States)

    Liehr, Patricia; Sopcheck, Janet; Milbrath, Gwyneth

    2016-12-01

    : On December 7, 1941, the Sunday-morning quiet of the U.S. naval base in Pearl Harbor, Hawaii, was shattered by dive-bombing Japanese fighter planes. The planes came in two waves-and when it was all over, more than 2,400 were killed and more than 1,100 were injured.Nurses were stationed at U.S. Naval Hospital Pearl Harbor, Tripler General Hospital (now Tripler Army Medical Center), Hickam Field Hospital, Schofield Barracks Station Hospital, and aboard the USS Solace, and witnessed the devastation. But they also did what nurses do in emergencies-they responded and provided care to those in need. Here are the stories of a few of those nurses.

  9. The Physiology and Mechanics of Undulatory Swimming: A Student Laboratory Exercise Using Medicinal Leeches

    Science.gov (United States)

    Ellerby, David J.

    2009-01-01

    The medicinal leech is a useful animal model for investigating undulatory swimming in the classroom. Unlike many swimming organisms, its swimming performance can be quantified without specialized equipment. A large blood meal alters swimming behavior in a way that can be used to generate a discussion of the hydrodynamics of swimming, muscle…

  10. Upward swimming of a sperm cell in shear flow.

    Science.gov (United States)

    Omori, Toshihiro; Ishikawa, Takuji

    2016-03-01

    Mammalian sperm cells are required to swim over long distances, typically around 1000-fold their own length. They must orient themselves and maintain a swimming motion to reach the ovum, or egg cell. Although the mechanism of long-distance navigation is still unclear, one possible mechanism, rheotaxis, was reported recently. This work investigates the mechanism of the rheotaxis in detail by simulating the motions of a sperm cell in shear flow adjacent to a flat surface. A phase diagram was developed to show the sperm's swimming motion under different shear rates, and for varying flagellum waveform conditions. The results showed that, under shear flow, the sperm is able to hydrodynamically change its swimming direction, allowing it to swim upwards against the flow, which suggests that the upward swimming of sperm cells can be explained using fluid mechanics, and this can then be used to further understand physiology of sperm cell navigation.

  11. The fluid dynamics of swimming by jumping in copepods

    DEFF Research Database (Denmark)

    Jiang, Houshuo; Kiørboe, Thomas

    2011-01-01

    Copepods swim either continuously by vibrating their feeding appendages or erratically by repeatedly beating their swimming legs resulting in a series of small jumps. The two swimming modes generate different hydrodynamic disturbances and therefore expose the swimmers differently to rheotactic...... limited and temporally ephemeral owing to jump-impulsiveness and viscous decay. In contrast, continuous steady swimming generates two well-extended long-lasting momentum jets both in front of and behind the swimmer, as suggested by the well-known steady stresslet model. Based on the observed jump-swimming...... kinematics of a small copepod Oithona davisae, we further showed that jump-swimming produces a hydrodynamic disturbance with much smaller spatial extension and shorter temporal duration than that produced by a same-size copepod cruising steadily at the same average translating velocity. Hence, small copepods...

  12. SWIMMING CLASSES IN JUNIOR HIGH SCHOOL STUDENTS’ OPINION

    Directory of Open Access Journals (Sweden)

    Grzegorz Bielec

    2013-02-01

    Full Text Available The role of modern physical education is not only to develop motor abilities of the students, but most of all prevent them from epidemic youth diseases such as obesity or postural defects. Positive attitudes to swimming as a long-life physical activity, instilled in adolescence should be beneficial in adult life. The group of 130 boys and 116 girls of 7th grade junior high school (mean age 14.6 was asked in the survey to present their opinion of obligatory swimming lessons at school. Students of both sexes claimed that they liked swimming classes because they could improve their swimming skills (59% of answers and because of health-related character of water exercises (38%. 33% of students regarded swimming lessons as boring and monotonous, and 25% of them complained about poor pool conditions like chlorine smell, crowded lanes, too low temperature. Majority of the surveyed students saw practical role of swimming in saving others life.

  13. Old Harbor Scammon Bay Hydro Feasibility

    Energy Technology Data Exchange (ETDEWEB)

    Brent Petrie

    2007-06-27

    The grantee, Alaska Village Electric Cooperative (AVEC), is a non-profit member owned rural electric generation and distribution cooperative. The proposed Project is located near the community of Old Harbor, Alaska. Old Harbor is on the southeastern coast of Kodiak Island, approximately 70 miles southwest of the City of Kodiak and 320 miles southwest of Anchorage. In 1998 sufficient information had been developed to apply for a license to construct the project and the cost was estimated to be $2,445,000 for a 500 KW project on Lagoon Creek. Major features of the project included an eight-foot high diversion dam on Mountain Creek, a desander box, a 9,800-foot long penstock to the powerhouse on Lagoon Creek, and a 5,500-foot long access road. It was also anticipated that the project could provide an additional source of water to Old Harbor. The report details the history and lessons learned in designing and permiting the proposed hydroelectric facility.

  14. Laryngoscopy during swimming: A novel diagnostic technique to characterize swimming-induced laryngeal obstruction.

    Science.gov (United States)

    Walsted, Emil S; Swanton, Laura L; van van Someren, Ken; Morris, Tessa E; Furber, Matthew; Backer, Vibeke; Hull, James H

    2017-10-01

    Exercise-induced laryngeal obstruction (EILO) is a key differential diagnosis for respiratory symptoms in athletes and is particularly prevalent in aquatic athletes. A definitive diagnosis of EILO is dependent on laryngoscopy, performed continuously, while an athlete engages in the sport that precipitates their symptoms. This report provides the first description of the feasibility of performing continuous laryngoscopy during exercise in a swimming environment. The report describes the methodology and safety of the use of continuous laryngoscopy while swimming. Laryngoscope, 127:2298-2301, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  15. TECHNIQUE AND METHODOLOGY OF TRAINING IN SWIMMING CRAWL

    Directory of Open Access Journals (Sweden)

    Selim Alili

    2013-07-01

    Full Text Available The paper shows the technique and methodology training crawl swimming. Developed: the position of the head and body, footwork, hand movements, exercises for training footwork training drills and exercises for improving coordination technique on dry land and in water. Stated that accomplishes this swimmer swimming technique allows fast and is the fastest discipline. Therefore we can say that it is a favorite way of swimming and a pleasure to watch on the big stage.

  16. Swimming of Microorganisms Viewed from String and Membrane Theories

    OpenAIRE

    Kawamura, Masako; Sugamoto, Akio; Nojiri, Shin'ichi

    1993-01-01

    Swimming of microorganisms is studied from a viewpoint of extended objects (strings and membranes) swimming in the incompressible f luid of low Reynolds number. The flagellated motion is analyzed in two dimensional fluid, by using the method developed in the ciliated motion with the Joukowski transformation. Discussion is given on the conserved charges and the algebra which are associated with the area (volume)- preserving diffeomorphisms giving the swimming motion of microorganisms. It is al...

  17. Roll and Yaw of Paramecium swimming in a viscous fluid

    Science.gov (United States)

    Jung, Sunghwan; Jana, Saikat; Giarra, Matt; Vlachos, Pavlos

    2012-11-01

    Many free-swimming microorganisms like ciliates, flagellates, and invertebrates exhibit helical trajectories. In particular, the Paramecium spirally swims along its anterior direction by the beating of cilia. Due to the oblique beating stroke of cilia, the Paramecium rotates along its long axis as it swims forward. Simultaneously, this long axis turns toward the oral groove side. Combined roll and yaw motions of Paramecium result in swimming along a spiral course. Using Particle Image Velocimetry, we measure and quantify the flow field and fluid stress around Paramecium. We will discuss how the non-uniform stress distribution around the body induces this yaw motion.

  18. Biomechanical Analysis of the Swim-Start: A Review

    Directory of Open Access Journals (Sweden)

    Julien Vantorre, Didier Chollet, Ludovic Seifert

    2014-06-01

    Full Text Available This review updates the swim-start state of the art from a biomechanical standpoint. We review the contribution of the swim-start to overall swimming performance, the effects of various swim-start strategies, and skill effects across the range of swim-start strategies identified in the literature. The main objective is to determine the techniques to focus on in swimming training in the contemporary context of the sport. The phases leading to key temporal events of the swim-start, like water entry, require adaptations to the swimmer’s chosen technique over the course of a performance; we thus define the swim-start as the moment when preparation for take-off begins to the moment when the swimming pattern begins. A secondary objective is to determine the role of adaptive variability as it emerges during the swim-start. Variability is contextualized as having a functional role and operating across multiple levels of analysis: inter-subject (expert versus non-expert, inter-trial or intra-subject (through repetitions of the same movement, and inter-preference (preferred versus non-preferred technique. Regarding skill effects, we assume that swim-start expertise is distinct from swim stroke expertise. Highly skilled swim-starts are distinguished in terms of several factors: reaction time from the start signal to the impulse on the block, including the control and regulation of foot force and foot orientation during take-off; appropriate amount of glide time before leg kicking commences; effective transition from leg kicking to break-out of full swimming with arm stroking; overall maximal leg and arm propulsion and minimal water resistance; and minimized energy expenditure through streamlined body position. Swimmers who are less expert at the swim-start spend more time in this phase and would benefit from training designed to reduce: (i the time between reaction to the start signal and impulse on the block, and (ii the time in transition (i

  19. Flow disturbances generated by feeding and swimming zooplankton

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Jiang, Haisong; Goncalves, R. J.

    2014-01-01

    that zooplankton, in which feeding and swimming are separate processes, produce flow disturbances during swimming with a much faster spatial attenuation (velocity u varies with distance r as u ∝ r−3 to r−4) than that produced by zooplankton for which feeding and propulsion are the same process (u ∝ r−1 to r−2...... vortex rings, or by “breast-stroke swimming.” Both produce rapidly attenuating flows. The more “noisy” swimming of those that are constrained by a need to simultaneously feed is due to constantly beating flagella or appendages that are positioned either anteriorly or posteriorly on the (cell) body...

  20. Creatine supplementation and swim performance: a brief review.

    Science.gov (United States)

    Hopwood, Melissa J; Graham, Kenneth; Rooney, Kieron B

    2006-03-01

    Nutritional supplements are popular among athletes participating in a wide variety of sports. Creatine is one of the most commonly used dietary supplements, as it has been shown to be beneficial in improving performance during repeated bouts of high-intensity anaerobic activity. This review examines the specific effects of creatine supplementation on swimming performance, and considers the effects of creatine supplementation on various measures of power development in this population. Research performed on the effect of creatine supplementation on swimming performance indicates that whilst creatine supplementation is ineffective in improving performance during a single sprint swim, dietary creatine supplementation may benefit repeated interval swim set performance. Considering the relationship between sprint swimming performance and measurements of power, the effect of creatine supplementation on power development in swimmers has also been examined. When measured on a swim bench ergometer, power development does show some improvement following a creatine supplementation regime. How this improvement in power output transfers to performance in the pool is uncertain. Although some evidence exists to suggest a gender effect on the performance improvements seen in swimmers following creatine supplementation, the majority of research indicates that male and female swimmers respond equally to supplementation. A major limitation to previous research is the lack of consideration given to the possible stroke dependant effect of creatine supplementation on swimming performance. The majority of the research conducted to date has involved examination of the freestyle swimming stroke only. The potential for performance improvements in the breaststroke and butterfly swimming strokes is discussed, with regards to the biomechanical differences and differences in efficiency between these strokes and freestyle. Key PointsCreatine supplementation does not improve single sprint

  1. Zebrafish swimming in the flow: a particle image velocimetry study

    Directory of Open Access Journals (Sweden)

    Violet Mwaffo

    2017-11-01

    Full Text Available Zebrafish is emerging as a species of choice for the study of a number of biomechanics problems, including balance development, schooling, and neuromuscular transmission. The precise quantification of the flow physics around swimming zebrafish is critical toward a mechanistic understanding of the complex swimming style of this fresh-water species. Although previous studies have elucidated the vortical structures in the wake of zebrafish swimming in placid water, the flow physics of zebrafish swimming against a water current remains unexplored. In an effort to illuminate zebrafish swimming in a dynamic environment reminiscent of its natural habitat, we experimentally investigated the locomotion and hydrodynamics of a single zebrafish swimming in a miniature water tunnel using particle image velocimetry. Our results on zebrafish locomotion detail the role of flow speed on tail beat undulations, heading direction, and swimming speed. Our findings on zebrafish hydrodynamics offer a precise quantification of vortex shedding during zebrafish swimming and demonstrate that locomotory patterns play a central role on the flow physics. This knowledge may help clarify the evolutionary advantage of burst and cruise swimming movements in zebrafish.

  2. Scaling the Thrust Production and Energetics of Inviscid Intermittent Swimming

    Science.gov (United States)

    Akoz, Emre; Moored, Keith

    2015-11-01

    Many fish have adopted an intermittent swimming gait sometimes referred as a burst-and-coast behavior. By using this gait, fish have been estimated at reducing their energetic cost of swimming by about 50%. Lighthill proposed that the skin friction drag of an undulating body can be around 400% greater than a rigidly-held coasting body, which may explain the energetic savings of intermittent swimming. Recent studies have confirmed the increase in skin friction drag over an undulating body, however, the increase is on the order of 20-70%. This more modest gain in skin friction drag is not sufficient to lead to the observed energy savings. Motivated by these observations, we investigate the inviscid mechanisms behind intermittent swimming for parameters typical of biology. We see that there is an energy savings at a fixed swimming speed for intermittent swimming as compared to continuous swimming. Then we consider three questions: What is the nature of the inviscid mechanism that leads to the observed energy savings, how do the forces and energetics of intermittent swimming scale with the swimming parameters, and what are the limitations to the benefit? Supported by the Office of Naval Research under Program Director Dr. Bob Brizzola, MURI grant number N00014-14-1-0533.

  3. Water Penetration into Middle Ear Through Ventilation Tubes in Children While Swimming

    Directory of Open Access Journals (Sweden)

    Mao-Che Wang

    2009-02-01

    Conclusion: Water penetration into the middle ear through ventilation tubes and middle ear infection are not likely when surface swimming. Children with ventilation tubes can enjoy swimming without protection in clean chlorinated swimming pools.

  4. TUNING IN TO FISH SWIMMING WAVES - BODY FORM, SWIMMING MODE AND MUSCLE FUNCTION

    NARCIS (Netherlands)

    WARDLE, CS; VIDELER, JJ; ALTRINGHAM, JD

    Most fish species swim with lateral body undulations running from head to tail, These waves run more slowly than the waves of muscle activation causing them, reflecting the effect of the interaction between the fish's body and the reactive forces from the water, The coupling between both waves

  5. The Effect of Concurrent Visual Feedback on Controlling Swimming Speed

    Directory of Open Access Journals (Sweden)

    Szczepan Stefan

    2016-03-01

    Full Text Available Introduction. Developing the ability to control the speed of swimming is an important part of swimming training. Maintaining a defined constant speed makes it possible for the athlete to swim economically at a low physiological cost. The aim of this study was to determine the effect of concurrent visual feedback transmitted by the Leader device on the control of swimming speed in a single exercise test. Material and methods. The study involved a group of expert swimmers (n = 20. Prior to the experiment, the race time for the 100 m distance was determined for each of the participants. In the experiment, the participants swam the distance of 100 m without feedback and with visual feedback. In both variants, the task of the participants was to swim the test distance in a time as close as possible to the time designated prior to the experiment. In the first version of the experiment (without feedback, the participants swam the test distance without receiving real-time feedback on their swimming speed. In the second version (with visual feedback, the participants followed a beam of light moving across the bottom of the swimming pool, generated by the Leader device. Results. During swimming with visual feedback, the 100 m race time was significantly closer to the time designated. The difference between the pre-determined time and the time obtained was significantly statistically lower during swimming with visual feedback (p = 0.00002. Conclusions. Concurrently transmitting visual feedback to athletes improves their control of swimming speed. The Leader device has proven useful in controlling swimming speed.

  6. Swimming pool reactor reliability and safety analysis

    International Nuclear Information System (INIS)

    Li Zhaohuan

    1997-01-01

    A reliability and safety analysis of Swimming Pool Reactor in China Institute of Atomic Energy is done by use of event/fault tree technique. The paper briefly describes the analysis model, analysis code and main results. Meanwhile it also describes the impact of unassigned operation status on safety, the estimation of effectiveness of defense tactics in maintenance against common cause failure, the effectiveness of recovering actions on the system reliability, the comparison of occurrence frequencies of the core damage by use of generic and specific data

  7. Cultural Resources Survey of Mobile Harbor, Alabama.

    Science.gov (United States)

    1983-01-01

    improvement from the point of view of supply and communication with other European settlements, since it cut the lightering distance to the capital in half...order to cut the costs of building (Bathe 1978:08.00-02; Millar 1978:15-29). 32 6e The sharing of ship builders, the borrowing of vessel lines and the... Eslava Street Mobile. Burned to water’s edge during overhaul. Notes: Served as HINGHAM in Boston Harbor; served as ORIENT in Long Island Sound. Operated

  8. Swimming direction reversal of flagella through ciliary motion of mastigonemes

    NARCIS (Netherlands)

    Namdeo, S.; Khaderi, S. N.; den Toonder, J.M.J.; Onck, P. R.; Colin, S.; Morini, G.L.

    Bio-inspired designs can provide an answer to engineering problems such as swimming strategies at the micron or nano-scale. Scientists are now designing artificial micro-swimmers that can mimic flagella-powered swimming of micro-organisms. In an application such as lab-on-a-chip in which

  9. Solar collectors for swimming pools still going strong

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-01

    According to the opinion of the experts, solar energy heating may be technically 'mature' but the profitability is by no means that far. However, solar systems are a good alternative for heating the water in swimming pools. Four solar collector systems developed by different firms to heat swimming pools, including prices, are presented.

  10. Swimming performance of a biomimetic compliant fish-like robot

    Science.gov (United States)

    Epps, Brenden P.; Valdivia Y Alvarado, Pablo; Youcef-Toumi, Kamal; Techet, Alexandra H.

    2009-12-01

    Digital particle image velocimetry and fluorescent dye visualization are used to characterize the performance of fish-like swimming robots. During nominal swimming, these robots produce a ‘V’-shaped double wake, with two reverse-Kármán streets in the far wake. The Reynolds number based on swimming speed and body length is approximately 7500, and the Strouhal number based on flapping frequency, flapping amplitude, and swimming speed is 0.86. It is found that swimming speed scales with the strength and geometry of a composite wake, which is constructed by freezing each vortex at the location of its centroid at the time of shedding. Specifically, we find that swimming speed scales linearly with vortex circulation. Also, swimming speed scales linearly with flapping frequency and the width of the composite wake. The thrust produced by the swimming robot is estimated using a simple vortex dynamics model, and we find satisfactory agreement between this estimate and measurements made during static load tests.

  11. A meta-analysis of steady undulatory swimming

    NARCIS (Netherlands)

    van Weerden, J. Fransje; Reid, Daniel A. P.; Hemelrijk, Charlotte K.

    The mechanics underlying undulatory swimming are of great general interest, both to biologists and to engineers. Over the years, more data of the kinematics of undulatory swimming have been reported. At present, an integrative analysis is needed to determine which general relations hold between

  12. Glucocorticoids facilitate the retention of acquired immobility during forced swimming

    NARCIS (Netherlands)

    Veldhuis, H D; De Korte, C C; De Kloet, E R

    1985-01-01

    The adrenalectomy-induced decrease in the level of immobility during a 5 min retest period in the Porsolt swimming test could be reversed by glucocorticoids administered s.c. 15 min after the initial forced swimming exposure. The synthetic glucocorticoids dexamethasone and RU 28362 were active in

  13. 33 CFR 117.734 - Navesink River (Swimming River).

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navesink River (Swimming River). 117.734 Section 117.734 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... (Swimming River). The Oceanic Bridge, mile 4.5, shall open on signal; except that, from December 1 through...

  14. Geometric Aspects of Force Controllability for a Swimming Model

    International Nuclear Information System (INIS)

    Khapalov, A. Y.

    2008-01-01

    We study controllability properties (swimming capabilities) of a mathematical model of an abstract object which 'swims' in the 2-D Stokes fluid. Our goal is to investigate how the geometric shape of this object affects the forces acting upon it. Such problems are of interest in biology and engineering applications dealing with propulsion systems in fluids

  15. Health risks associated with swimming at an inland river

    Science.gov (United States)

    Swimming exposure to fecally-contaminated oceans and lakes has been associated with an increased risk of gastrointestinal (GI) illness. Although treated and untreated sewage are often discharged to rivers, the health risks of swimming exposure on rivers has been less frequently ...

  16. Biomechanical aspects of peak performance in human swimming

    NARCIS (Netherlands)

    Toussaint, H.M.; Truijens, M.J.

    2005-01-01

    Peak performances in sport require the full deployment of all the powers an athlete possesses. How factors such as mechanical power output, technique and drag, each individually, but also in concert, determine swimming performance is the subject of this enquiry. This overview of swimming

  17. Body dynamics and hydrodynamics of swimming larvae: a computational study

    NARCIS (Netherlands)

    Li, G.; Müller, U.K.; Leeuwen, van J.L.; Liu, H.

    2012-01-01

    To understand the mechanics of fish swimming, we need to know the forces exerted by the fluid and how these forces affect the motion of the fish. To this end, we developed a 3-D computational approach that integrates hydrodynamics and body dynamics. This study quantifies the flow around a swimming

  18. Swimming efficiency in a shear-thinning fluid

    Science.gov (United States)

    Nganguia, Herve; Pietrzyk, Kyle; Pak, On Shun

    2017-12-01

    Micro-organisms expend energy moving through complex media. While propulsion speed is an important property of locomotion, efficiency is another factor that may determine the swimming gait adopted by a micro-organism in order to locomote in an energetically favorable manner. The efficiency of swimming in a Newtonian fluid is well characterized for different biological and artificial swimmers. However, these swimmers often encounter biological fluids displaying shear-thinning viscosities. Little is known about how this nonlinear rheology influences the efficiency of locomotion. Does the shear-thinning rheology render swimming more efficient or less? How does the swimming efficiency depend on the propulsion mechanism of a swimmer and rheological properties of the surrounding shear-thinning fluid? In this work, we address these fundamental questions on the efficiency of locomotion in a shear-thinning fluid by considering the squirmer model as a general locomotion model to represent different types of swimmers. Our analysis reveals how the choice of surface velocity distribution on a squirmer may reduce or enhance the swimming efficiency. We determine optimal shear rates at which the swimming efficiency can be substantially enhanced compared with the Newtonian case. The nontrivial variations of swimming efficiency prompt questions on how micro-organisms may tune their swimming gaits to exploit the shear-thinning rheology. The findings also provide insights into how artificial swimmers should be designed to move through complex media efficiently.

  19. Critical evaluation of oxygen-uptake assessment in swimming.

    Science.gov (United States)

    Sousa, Ana; Figueiredo, Pedro; Pendergast, David; Kjendlie, Per-Ludvik; Vilas-Boas, João P; Fernandes, Ricardo J

    2014-03-01

    Swimming has become an important area of sport science research since the 1970s, with the bioenergetic factors assuming a fundamental performance-influencing role. The purpose of this study was to conduct a critical evaluation of the literature concerning oxygen-uptake (VO2) assessment in swimming, by describing the equipment and methods used and emphasizing the recent works conducted in ecological conditions. Particularly in swimming, due to the inherent technical constraints imposed by swimming in a water environment, assessment of VO2max was not accomplished until the 1960s. Later, the development of automated portable measurement devices allowed VO2max to be assessed more easily, even in ecological swimming conditions, but few studies have been conducted in swimming-pool conditions with portable breath-by-breath telemetric systems. An inverse relationship exists between the velocity corresponding to VO2max and the time a swimmer can sustain it at this velocity. The energy cost of swimming varies according to its association with velocity variability. As, in the end, the supply of oxygen (whose limitation may be due to central-O2 delivery and transportation to the working muscles-or peripheral factors-O2 diffusion and utilization in the muscles) is one of the critical factors that determine swimming performance, VO2 kinetics and its maximal values are critical in understanding swimmers' behavior in competition and to develop efficient training programs.

  20. Nutrition considerations for open-water swimming.

    Science.gov (United States)

    Shaw, Gregory; Koivisto, Anu; Gerrard, David; Burke, Louise M

    2014-08-01

    Open-water swimming (OWS) is a rapidly developing discipline. Events of 5-25 km are featured at FINA World Championships, and the international circuit includes races of 5-88 km. The Olympic OWS event, introduced in 2008, is contested over 10 km. Differing venues present changing environmental conditions, including water and ambient temperatures, humidity, solar radiation, and unpredictable tides. Furthermore, the duration of most OWS events (1-6 hr) creates unique physiological challenges to thermoregulation, hydration status, and muscle fuel stores. Current nutrition recommendations for open-water training and competition are either an extension of recommendations from pool swimming or are extrapolated from other athletic populations with similar physiological requirements. Competition nutrition should focus on optimizing prerace hydration and glycogen stores. Although swimmers should rely on self-supplied fuel and fluid sources for shorter events, for races of 10 km or greater, fluid and fuel replacement can occur from feeding pontoons when tactically appropriate. Over the longer races, feeding pontoons should be used to achieve desirable targets of up to 90 g/ hr of carbohydrates from multitransportable sources. Exposure to variable water and ambient temperatures will play a significant role in determining race nutrition strategies. For example, in extreme environments, thermoregulation may be assisted by manipulating the temperature of the ingested fluids. Swimmers are encouraged to work with nutrition experts to develop effective and efficient strategies that enhance performance through appropriate in-competition nutrition.

  1. Viscoelasticity promotes collective swimming of sperm

    Science.gov (United States)

    Tung, Chih-Kuan; Harvey, Benedict B.; Fiore, Alyssa G.; Ardon, Florencia; Suarez, Susan S.; Wu, Mingming

    From flocking birds to swarming insects, interactions of organisms large and small lead to the emergence of collective dynamics. Here, we report striking collective swimming of bovine sperm, with sperm orienting in the same direction within each cluster, enabled by the viscoelasticity of the fluid. A long-chain polyacrylamide solution was used as a model viscoelastic fluid such that its rheology can be fine-tuned to mimic that of bovine cervical mucus. In viscoelastic fluid, sperm formed dynamic clusters, and the cluster size increased with elasticity of the polyacrylamide solution. In contrast, sperm swam randomly and individually in Newtonian fluids of similar viscosity. Analysis of the fluid motion surrounding individual swimming sperm indicated that sperm-fluid interaction is facilitated by the elastic component of the fluid. We note that almost all biological fluids (e.g. mucus and blood) are viscoelastic in nature, this finding highlights the importance of fluid elasticity in biological function. We will discuss what the orientation fluctuation within a cluster reveals about the interaction strength. Supported by NIH Grant 1R01HD070038.

  2. EFFECT OF FLEXIBILITY ON THE RESULTS OF DOLPHIN SWIMMING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Slađana Tošić

    2011-09-01

    Full Text Available In order to determine the impact of flexibility on the results in swimming, we conducted a study on a sample of 50 female patients aged 11-14 years of age who are in the training process in the swimming clubs „Nis 2005“ and „Sveti Nikola“ in Nis. The study is applied to 14 measuring instruments that were divided into three groups: Measuring instruments for the assessment of flexibility (11; Measuring instruments for assessing the results of swimming (1; Measuring instruments for evaluation of morphological characteristics (2. The regression analysis determined the impact of flexibility on the results in swimming. The regression analysis didn't confirmed the assumption that there is a statistically significant effect of flexibility variables on results in swimming for female swimmers

  3. EFFECTS OF THREE FEEDBACK CONDITIONS ON AEROBIC SWIM SPEEDS

    Directory of Open Access Journals (Sweden)

    Pedro Pérez Soriano

    2009-03-01

    Full Text Available The purpose of this study was twofold: (a to develop an underwater chronometer capable to provide feedback while the athlete is swimming, as well as being a control tool for the coach, and (b to analyse its feedback effect on swim pace control compared with feedback provided by the coach and with no feedback, in 25 m and 50 m swimming pools. 30 male swimmers of national level volunteer to participate. Each swimmer swam 3 x 200 m at aerobic speed (AS and 3 x 200 m just under the anaerobic threshold speed (AnS, each swam repetition with a different feedback condition: chronometer, coach and without feedback. Results (a validate the chronometer system developed and (b show that swimmers pace control is affected by the type of feedback provided, the swim speed elected and the size of the swimming pool

  4. 77 FR 50916 - Safety Zone; Boston Harbor's Rock Removal Project, Boston Inner Harbor, Boston, MA

    Science.gov (United States)

    2012-08-23

    ... operation on the navigable waters of Boston Inner Harbor, in the main ship channel near Castle Island. This... operations in support of the U.S. Army Corps of Engineers rock removal project. Entering into, transiting... before the start date of the project. The U.S. Army Corps of Engineers also discussed the rock removal...

  5. Vibration-based structural health monitoring of harbor caisson structure

    Science.gov (United States)

    Lee, So-Young; Lee, So-Ra; Kim, Jeong-Tae

    2011-04-01

    This study presents vibration-based structural health monitoring method in foundation-structure interface of harbor caisson structure. In order to achieve the objective, the following approaches are implemented. Firstly, vibration-based response analysis method is selected and structural health monitoring (SHM) technique is designed for harbor caisson structure. Secondly, the performance of designed SHM technique for harbor structure is examined by FE analysis. Finally, the applicability of designed SHM technique for harbor structure is evaluated by dynamic tests on a lab-scaled caisson structure.

  6. Swimming and Persons with Mild Persistant Asthma

    Directory of Open Access Journals (Sweden)

    Mirjana Arandelovic

    2007-01-01

    Full Text Available The aim of our study was to analyze the effect of recreational swimming on lung function and bronchial hyperresponsiveness (BHR in patients with mild persistent asthma. This study included 65 patients with mild persistent asthma, who were divided into two groups: experimental group A (n = 45 and control group B (n = 20. Patients from both groups were treated with low doses of inhaled corticosteroids (ICS and short-acting β2 agonists salbutamol as needed. Our program for patients in group A was combined asthma education with swimming (twice a week on a 1-h basis for the following 6 months. At the end of the study, in Group A, we found a statistically significant increase of lung function parameters FEV1 (forced expiratory volume in 1 sec (3.55 vs. 3.65 (p < 0.01, FVC (forced vital capacity (4.27 vs. 4.37 (p < 0.05, PEF (peak expiratory flow (7.08 vs. 7.46 (p < 0.01, and statistically significant decrease of BHR (PD20 0.58 vs. 2.01 (p < 0.001. In Group B, there was a statistically significant improvement of FEV1 3.29 vs. 3.33 (p < 0.05 and although FVC, FEV1/FVC, and PEF were improved, it was not significant. When Groups A and B were compared at the end of the study, there was a statistically significant difference of FVC (4.01 vs. 4.37, FEV1 (3.33 vs. 3.55, PEF (6.79 vs.7.46, and variability (p <0.001, and statistically significantly decreased BHR in Group A (2.01 vs. 1.75 (p < 0.001. Engagement of patients with mild persistent asthma in recreational swimming in nonchlorinated pools, combined with regular medical treatment and education, leads to better improvement of their parameters of lung function and also to more significant decrease of their airway hyperresponsiveness compared to patients treated with traditional medicine

  7. To Swim or Not to Swim: Potential Transmission of Balaenophilus manatorum (Copepoda: Harpacticoida) in Marine Turtles.

    Science.gov (United States)

    Domènech, Francesc; Tomás, Jesús; Crespo-Picazo, José Luis; García-Párraga, Daniel; Raga, Juan Antonio; Aznar, Francisco Javier

    2017-01-01

    Species of Balaenophilus are the only harpacticoid copepods that exhibit a widespread, obligate association with vertebrates, i.e., B. unisetus with whales and B. manatorum with marine turtles and manatees. In the western Mediterranean, juveniles of the loggerhead sea turtle, Caretta caretta are the only available hosts for B. manatorum, which has been found occurring at high prevalence (>80%) on them. A key question is how these epibionts are transmitted from host to host. We investigated this issue based on experiments with live specimens of B. manatorum that were cultured with turtle skin. Specimens were obtained from head-started hatchlings of C. caretta from the western Mediterranean. Hatched nauplii crawled only on rough substrates and lacked the ability to swim. Only copepodites IV and V, and adults, were able to perform directional swimming. Legs 2, 3 and 4 played a major role in swimming and were only well-developed in these stages. Nauplii reared in wells with turtle skin readily fed on this item. Late copepodites and adults also fed on turtle skin but did not consume other potential food items such as fish skin, baleen plates or planktonic algae. Evidences suggest that the transmission of B. manatorum should rely on hosts' bodily contacts and/or swimming of late developmental stages between spatially close hosts. The possibility of long-ranged dispersal is unlikely for two reasons. First, all developmental stages seem to depend on turtle skin as a food resource. Second, the average clutch size of ovigerous females was small (turtles that occur at very low densities (turtles·km-2) in the western Mediterranean. The high prevalence of B. manatorum in loggerhead turtles in this area raises the question whether these turtles have contacts, or tend to closely aggregate, more than is currently believed.

  8. To Swim or Not to Swim: Potential Transmission of Balaenophilus manatorum (Copepoda: Harpacticoida in Marine Turtles.

    Directory of Open Access Journals (Sweden)

    Francesc Domènech

    Full Text Available Species of Balaenophilus are the only harpacticoid copepods that exhibit a widespread, obligate association with vertebrates, i.e., B. unisetus with whales and B. manatorum with marine turtles and manatees. In the western Mediterranean, juveniles of the loggerhead sea turtle, Caretta caretta are the only available hosts for B. manatorum, which has been found occurring at high prevalence (>80% on them. A key question is how these epibionts are transmitted from host to host. We investigated this issue based on experiments with live specimens of B. manatorum that were cultured with turtle skin. Specimens were obtained from head-started hatchlings of C. caretta from the western Mediterranean. Hatched nauplii crawled only on rough substrates and lacked the ability to swim. Only copepodites IV and V, and adults, were able to perform directional swimming. Legs 2, 3 and 4 played a major role in swimming and were only well-developed in these stages. Nauplii reared in wells with turtle skin readily fed on this item. Late copepodites and adults also fed on turtle skin but did not consume other potential food items such as fish skin, baleen plates or planktonic algae. Evidences suggest that the transmission of B. manatorum should rely on hosts' bodily contacts and/or swimming of late developmental stages between spatially close hosts. The possibility of long-ranged dispersal is unlikely for two reasons. First, all developmental stages seem to depend on turtle skin as a food resource. Second, the average clutch size of ovigerous females was small (< 70 eggs for free-living phases to successfully contact turtles that occur at very low densities (< 0.6 turtles·km-2 in the western Mediterranean. The high prevalence of B. manatorum in loggerhead turtles in this area raises the question whether these turtles have contacts, or tend to closely aggregate, more than is currently believed.

  9. Mechanical Study of Standard Six Beat Front Crawl Swimming by Using Swimming Human Simulation Model

    Science.gov (United States)

    Nakashima, Motomu

    There are many dynamical problems in front crawl swimming which have not been fully investigated by analytical approaches. Therefore, in this paper, standard six beat front crawl swimming is analyzed by the swimming human simulation model SWUM, which has been developed by the authors. First, the outline of the simulation model, the joint motion for one stroke cycle, and the specifications of calculation are described respectively. Next, contribution of each fluid force component and of each body part to the thrust, effect of the flutter kick, estimation of the active drag, roll motion, and the propulsive efficiency are discussed respectively. The following results were theoretically obtained: The thrust is produced at the upper limb by the normal drag force component. The flutter kick plays a role in raising the lower half of the body. The active drag coefficient in the simulation becomes 0.082. Buoyancy determines the primal wave of the roll motion fluctuation. The propulsive efficiency in the simulation becomes 0.2.

  10. Forces and energetics of intermittent swimming

    Science.gov (United States)

    Floryan, Daniel; Van Buren, Tyler; Smits, Alexander J.

    2017-08-01

    Experiments are reported on intermittent swimming motions. Water tunnel experiments on a nominally two-dimensional pitching foil show that the mean thrust and power scale linearly with the duty cycle, from a value of 0.2 all the way up to continuous motions, indicating that individual bursts of activity in intermittent motions are independent of each other. This conclusion is corroborated by particle image velocimetry (PIV) flow visualizations, which show that the main vortical structures in the wake do not change with duty cycle. The experimental data also demonstrate that intermittent motions are generally energetically advantageous over continuous motions. When metabolic energy losses are taken into account, this conclusion is maintained for metabolic power fractions less than 1.

  11. Transitions between three swimming gaits in Paramecium escape.

    Science.gov (United States)

    Hamel, Amandine; Fisch, Cathy; Combettes, Laurent; Dupuis-Williams, Pascale; Baroud, Charles N

    2011-05-03

    Paramecium and other protists are able to swim at velocities reaching several times their body size per second by beating their cilia in an organized fashion. The cilia beat in an asymmetric stroke, which breaks the time reversal symmetry of small scale flows. Here we show that Paramecium uses three different swimming gaits to escape from an aggression, applied in the form of a focused laser heating. For a weak aggression, normal swimming is sufficient and produces a steady swimming velocity. As the heating amplitude is increased, a higher acceleration and faster swimming are achieved through synchronized beating of the cilia, which begin by producing oscillating swimming velocities and later give way to the usual gait. Finally, escape from a life-threatening aggression is achieved by a "jumping" gait, which does not rely on the cilia but is achieved through the explosive release of a group of trichocysts in the direction of the hot spot. Measurements through high-speed video explain the role of trichocysts in defending against aggressions while showing unexpected transitions in the swimming of microorganisms. These measurements also demonstrate that Paramecium optimizes its escape pattern by taking advantage of its inertia.

  12. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

    International Nuclear Information System (INIS)

    Weizman, R.; Weizman, A.; Kook, K.A.; Vocci, F.; Deutsch, S.I.; Paul, S.M.

    1989-01-01

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of [ 3 H]Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in [14C]iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress [an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures], although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results

  13. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Weizman, R.; Weizman, A.; Kook, K.A.; Vocci, F.; Deutsch, S.I.; Paul, S.M.

    1989-06-01

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of (/sup 3/H)Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in (14C)iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress (an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures), although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results.

  14. Health impact of disinfection by-products in swimming pools

    Directory of Open Access Journals (Sweden)

    Cristina M. Villanueva

    2012-12-01

    Full Text Available This article is focused on the epidemiological evidence on the health impacts related to disinfection by-products (DBPs in swimming pools, which is a chemical hazard generated as an undesired consequence to reduce the microbial pathogens. Specific DBPs are carcinogenic, fetotoxic and/or irritant to the airways according to experimental studies. Epidemiological evidence shows that swimming in pools during pregnancy is not associated with an increased risk of reproductive outcomes. An epidemiological study suggested an increased risk of bladder cancer with swimming pool attendance, although evidence is inconclusive. A higher prevalence of respiratory symptoms including asthma is found among swimming pool workers and elite swimmers, although the causality of this association is unclear. The body of evidence in children indicates that asthma is not increased by swimming pool attendance. Overall, the available knowledge suggests that the health benefits of swimming outweigh the potential health risks of chemical contamination. However, the positive effects of swimming should be enhanced by minimising potential risks.

  15. Hazardous substances shipping at inland water harbors

    International Nuclear Information System (INIS)

    Benkovic, Z.

    2009-01-01

    Safety measures and regulations system covering the aspects of fire protection, professional and ecological safety are aimed to create a safe working environment, by detection and remedy of conditions that are potentially hazardous for the well-being of the employees or are leading to certain undesired events. Such unwanted incidents may result in different consequences: operating person's injury, environment pollution or material damage. This study attempts to illustrate the organization of work during hazardous matter loading and unloading at inland water harbors, based on legal provisions and decrees involving safety precautions, and in order to achieve constant enhancement of operating procedure, decreasing thereby the number of work-related injuries and various accidental situations. Fundamental precondition required to prevent possible accidents and to optimize general safety policy is to recognize and control any danger or potential hazard, as well as to be familiar with the legal provisions covering the inland waterway transport of harmful substances.(author)

  16. CREATINE SUPPLEMENTATION AND SWIM PERFORMANCE: A BRIEF REVIEW

    Directory of Open Access Journals (Sweden)

    Melissa J. Hopwood

    2006-03-01

    Full Text Available Nutritional supplements are popular among athletes participating in a wide variety of sports. Creatine is one of the most commonly used dietary supplements, as it has been shown to be beneficial in improving performance during repeated bouts of high-intensity anaerobic activity. This review examines the specific effects of creatine supplementation on swimming performance, and considers the effects of creatine supplementation on various measures of power development in this population. Research performed on the effect of creatine supplementation on swimming performance indicates that whilst creatine supplementation is ineffective in improving performance during a single sprint swim, dietary creatine supplementation may benefit repeated interval swim set performance. Considering the relationship between sprint swimming performance and measurements of power, the effect of creatine supplementation on power development in swimmers has also been examined. When measured on a swim bench ergometer, power development does show some improvement following a creatine supplementation regime. How this improvement in power output transfers to performance in the pool is uncertain. Although some evidence exists to suggest a gender effect on the performance improvements seen in swimmers following creatine supplementation, the majority of research indicates that male and female swimmers respond equally to supplementation. A major limitation to previous research is the lack of consideration given to the possible stroke dependant effect of creatine supplementation on swimming performance. The majority of the research conducted to date has involved examination of the freestyle swimming stroke only. The potential for performance improvements in the breaststroke and butterfly swimming strokes is discussed, with regards to the biomechanical differences and differences in efficiency between these strokes and freestyle

  17. 36 CFR 3.17 - What regulations apply to swimming areas and beaches?

    Science.gov (United States)

    2010-07-01

    ... swimming areas and beaches? 3.17 Section 3.17 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.17 What regulations apply to swimming areas and beaches? (a) The superintendent may designate areas as swimming areas or swimming beaches in...

  18. On the development of inexpensive speed and position tracking system for swimming

    DEFF Research Database (Denmark)

    Trangbæk, Søren; Rasmussen, Cuno; Andersen, Thomas Bull

    2016-01-01

    A semi-automated tracking system was developed for the analysis of swimming, using cameras, an LED diode marker, and a red swim cap. Four experienced young swimmers were equipped with a marker and a swim cap and their position and speed was tracked throughout above-water and under-water swimming...

  19. Declines in swimming performance with age: a longitudinal study of Masters swimming champions

    Directory of Open Access Journals (Sweden)

    Rubin RT

    2013-03-01

    Full Text Available Robert T Rubin,1,2 Sonia Lin,3 Amy Curtis,4 Daniel Auerbach,5 Charlene Win6 1Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA; 2UCLA Bruin Masters Swim Club, Los Angeles, CA, USA; 3Saint Louis University School of Medicine, Saint Louis, MO, USA; 4Indiana University School of Medicine, Indianapolis, IN, USA; 5University of California, Berkeley, CA, USA; 6Loyola Marymount University, Los Angeles, CA, USA Introduction: Because of its many participants and thorough records, competitive Masters swimming offers a rich data source for determining the rate of physical decline associated with aging in physically fit individuals. The decline in performance among national champion swimmers, both men and women and in short and long swims, is linear, at about 0.6% per year up to age 70–75, after which it accelerates in quadratic fashion. These conclusions are based primarily on cross-sectional studies, and little is known about individual performance declines with aging. Herein we present performance profiles of 19 male and 26 female national and international champion Masters swimmers, ages 25 to 96 years, participating in competitions for an average of 23 years. Methods and results: Swimmers’ longitudinal data were compared with the fastest times of world record holders across ages 35–100 years by two regression methods. Neither method proved to accurately model this data set: compared with the rates of decline estimated from the world record data, which represent the best recorded times at given ages, there was bias toward shallower rates of performance decline in the longitudinal data, likely owing to a practice effect in some swimmers as they began their Masters programs. In swimmers’ later years, once maximum performance had been achieved, individual profiles followed the decline represented in the world records, and a few swimmers became the world record holders. In some instances

  20. 33 CFR 80.1460 - Kahului Harbor, Maui, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Kahului Harbor, Maui, HI. 80.1460 Section 80.1460 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1460 Kahului Harbor, Maui, HI. A line drawn...

  1. 33 CFR 80.1450 - Nawiliwili Harbor, Kauai, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Nawiliwili Harbor, Kauai, HI. 80.1450 Section 80.1450 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1450 Nawiliwili Harbor, Kauai, HI...

  2. 33 CFR 110.238 - Apra Harbor, Guam.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Apra Harbor, Guam. 110.238 Section 110.238 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.238 Apra Harbor, Guam. (a) The anchorage grounds (Datum: WGS...

  3. 33 CFR 80.1470 - Kawaihae Harbor, Hawaii, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Kawaihae Harbor, Hawaii, HI. 80.1470 Section 80.1470 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1470 Kawaihae Harbor, Hawaii, HI...

  4. 33 CFR 80.1480 - Hilo Harbor, Hawaii, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Hilo Harbor, Hawaii, HI. 80.1480 Section 80.1480 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1480 Hilo Harbor, Hawaii, HI. A line drawn...

  5. 33 CFR 110.208 - Buffalo Harbor, N.Y.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Buffalo Harbor, N.Y. 110.208 Section 110.208 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.208 Buffalo Harbor, N.Y. (a) The anchorage grounds—(1...

  6. 32 CFR 705.31 - USS Arizona Memorial, Pearl Harbor.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false USS Arizona Memorial, Pearl Harbor. 705.31... NAVY REGULATIONS AND OFFICIAL RECORDS PUBLIC AFFAIRS REGULATIONS § 705.31 USS Arizona Memorial, Pearl Harbor. (a) Limited space and the desirability of keeping the Memorial simple and dignified require the...

  7. 76 FR 50489 - Agency Information Collection Activities: Harbor Maintenance Fee

    Science.gov (United States)

    2011-08-15

    ... Activities: Harbor Maintenance Fee AGENCY: U.S. Customs and Border Protection, Department of Homeland... Fee (CBP Forms 349 and 350). This is a proposed extension of an information collection that was... Fee. OMB Number: 1651-0055. Form Number: CBP Forms 349 and 350. Abstract: The Harbor Maintenance Fee...

  8. Critical stroke rate as a parameter for evaluation in swimming

    Directory of Open Access Journals (Sweden)

    Marcos Franken

    2013-12-01

    Full Text Available The purpose of this study was to investigate the critical stroke rate (CSR compared to the average stroke rate (SR when swimming at the critical speed (CS. Ten competitive swimmers performed five 200 m trials at different velocities relative to their CS (90, 95, 100, 103 and 105% in front crawl. The CSR was significantly higher than the SR at 90% of the CS and lower at 105% of the CS. Stroke length (SL at 103 and 105% of the CS were lower than the SL at 90, 95, and 100% of the CS. The combination of the CS and CSR concepts can be useful for improving both aerobic capacity/power and technique. CS and CSR could be used to reduce the SR and increase the SL, when swimming at the CS pace, or to increase the swimming speed when swimming at the CSR.

  9. Avoiding Swimming Sickness (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    Pools, water parks, and other recreational water venues are popular places to relax and stay cool, but they can be sources of serious illness. In this podcast, Ashley Andujar discusses ways to stay safe while going swimming this summer.

  10. Allegheny County Public Swimming Pool, Hot Tub, and Spa Inspections

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Public swimming pool, hot tub, and spa facilities are licensed and inspected once each year to assure proper water quality, sanitation, lifeguard coverage and...

  11. Protection of swimming-induced oxidative stress in some vital ...

    African Journals Online (AJOL)

    Protection of swimming-induced oxidative stress in some vital organs by the treatment of composite extract of Withania somnifera, Ocimum sanctum and Zingiber officinalis in male rat. D Misra, B Maiti, D Ghosh ...

  12. Swimming Behavior of Individual Zooplankters During Night-Time Foraging

    National Research Council Canada - National Science Library

    McGehee, Duncan

    1998-01-01

    Amatzia Genin, Jules Jaffe, Duncan McGehee developed a method for automatically tracking individual plankters swimming through the imaging volume, and applied the method to track approximately 280,000 animals...

  13. Thermal analyses of solar swimming pool heating in Pakistan

    International Nuclear Information System (INIS)

    Ahmad, I.

    2011-01-01

    Hotels and swimming clubs in Pakistan pay huge gas bills for heating Swimming pools in winter. Winter days in most parts of Pakistan remain sunny and unglazed low cost solar collectors may be used to extend the swimming season. Installing the pool in a wind-protected area, which receives unobstructed solar radiation, may further reduce the size of the solar collectors required to heat the swimming pools. The pools should be covered with plastic sheet to eliminate evaporative heat losses and to prevent dust and tree leaves falling in the pool. The results of the thermal analysis show that in some parts of the country, a solar exposed pool can maintain comfortable temperature simply by using a plastic sheet on the pool surface. On the other hand, there are cities where solar collector array equal to twice the surface area of the pool is required to keep desired temperature in winter. (author)

  14. Safe Swimming (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    Swimmers can take simple steps to help protect themselves and others from germs that can spread in the water and cause illness. In this podcast Michele Hlavsa discusses ways to stay healthy while swimming.

  15. 33 CFR 165.904 - Lake Michigan at Chicago Harbor & Burnham Park Harbor-Safety and Security Zone.

    Science.gov (United States)

    2010-07-01

    ... & Burnham Park Harbor-Safety and Security Zone. 165.904 Section 165.904 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION... Guard District § 165.904 Lake Michigan at Chicago Harbor & Burnham Park Harbor—Safety and Security Zone...

  16. 77 FR 59551 - Safety Zone, Changes to Original Rule; Boston Harbor's Rock Removal Project, Boston Inner Harbor...

    Science.gov (United States)

    2012-09-28

    ... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2012-0767] RIN 1625-AA00 Safety Zone, Changes to Original Rule; Boston Harbor's Rock Removal Project, Boston Inner Harbor... original provisions of that temporary final rule, but adds two additional safety zones necessary for the...

  17. Exercise-training intervention studies in competitive swimming.

    Science.gov (United States)

    Aspenes, Stian Thoresen; Karlsen, Trine

    2012-06-01

    Competitive swimming has a long history and is currently one of the largest Olympic sports, with 16 pool events. Several aspects separate swimming from most other sports such as (i) the prone position; (ii) simultaneous use of arms and legs for propulsion; (iii) water immersion (i.e. hydrostatic pressure on thorax and controlled respiration); (iv) propulsive forces that are applied against a fluctuant element; and (v) minimal influence of equipment on performance. Competitive swimmers are suggested to have specific anthropometrical features compared with other athletes, but are nevertheless dependent on physiological adaptations to enhance their performance. Swimmers thus engage in large volumes of training in the pool and on dry land. Strength training of various forms is widely used, and the energetic systems are addressed by aerobic and anaerobic swimming training. The aim of the current review was to report results from controlled exercise training trials within competitive swimming. From a structured literature search we found 17 controlled intervention studies that covered strength or resistance training, assisted sprint swimming, arms-only training, leg-kick training, respiratory muscle training, training the energy delivery systems and combined interventions across the aforementioned categories. Nine of the included studies were randomized controlled trials. Among the included studies we found indications that heavy strength training on dry land (one to five repetitions maximum with pull-downs for three sets with maximal effort in the concentric phase) or sprint swimming with resistance towards propulsion (maximal pushing with the arms against fixed points or pulling a perforated bowl) may be efficient for enhanced performance, and may also possibly have positive effects on stroke mechanics. The largest effect size (ES) on swimming performance was found in 50 m freestyle after a dry-land strength training regimen of maximum six repetitions across three

  18. London 2012 Paralympic swimming: passive drag and the classification system.

    Science.gov (United States)

    Oh, Yim-Taek; Burkett, Brendan; Osborough, Conor; Formosa, Danielle; Payton, Carl

    2013-09-01

    The key difference between the Olympic and Paralympic Games is the use of classification systems within Paralympic sports to provide a fair competition for athletes with a range of physical disabilities. In 2009, the International Paralympic Committee mandated the development of new, evidence-based classification systems. This study aims to assess objectively the swimming classification system by determining the relationship between passive drag and level of swimming-specific impairment, as defined by the current swimming class. Data were collected on participants at the London 2012 Paralympic Games. The passive drag force of 113 swimmers (classes 3-14) was measured using an electro-mechanical towing device and load cell. Swimmers were towed on the surface of a swimming pool at 1.5 m/s while holding their most streamlined position. Passive drag ranged from 24.9 to 82.8 N; the normalised drag (drag/mass) ranged from 0.45 to 1.86 N/kg. Significant negative associations were found between drag and the swimming class (τ = -0.41, p < 0.01) and normalised drag and the swimming class (τ = -0.60, p < 0.01). The mean difference in drag between adjacent classes was inconsistent, ranging from 0 N (6 vs 7) to 11.9 N (5 vs 6). Reciprocal Ponderal Index (a measure of slenderness) correlated moderately with normalised drag (r(P) = -0.40, p < 0.01). Although swimmers with the lowest swimming class experienced the highest passive drag and vice versa, the inconsistent difference in mean passive drag between adjacent classes indicates that the current classification system does not always differentiate clearly between swimming groups.

  19. Trends in swimming training for individual medley events

    OpenAIRE

    Brtník, Tomáš

    2013-01-01

    Title: Trends in swimming training for individual medley events Objectives: The aim of our study was to analyze performance and training for 200 and 400 m individual medley events and describe new trends in training for these swimming events Methods: Our research design was a case study. We were interested in training of three swimmers of elite performance in the 200 and 400 m individual medley events. To identify cases, we used the analysis of documents and literature, to a limited extent, t...

  20. Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.

  1. Wearable inertial sensors in swimming motion analysis: a systematic review.

    Science.gov (United States)

    de Magalhaes, Fabricio Anicio; Vannozzi, Giuseppe; Gatta, Giorgio; Fantozzi, Silvia

    2015-01-01

    The use of contemporary technology is widely recognised as a key tool for enhancing competitive performance in swimming. Video analysis is traditionally used by coaches to acquire reliable biomechanical data about swimming performance; however, this approach requires a huge computational effort, thus introducing a delay in providing quantitative information. Inertial and magnetic sensors, including accelerometers, gyroscopes and magnetometers, have been recently introduced to assess the biomechanics of swimming performance. Research in this field has attracted a great deal of interest in the last decade due to the gradual improvement of the performance of sensors and the decreasing cost of miniaturised wearable devices. With the aim of describing the state of the art of current developments in this area, a systematic review of the existing methods was performed using the following databases: PubMed, ISI Web of Knowledge, IEEE Xplore, Google Scholar, Scopus and Science Direct. Twenty-seven articles published in indexed journals and conference proceedings, focusing on the biomechanical analysis of swimming by means of inertial sensors were reviewed. The articles were categorised according to sensor's specification, anatomical sites where the sensors were attached, experimental design and applications for the analysis of swimming performance. Results indicate that inertial sensors are reliable tools for swimming biomechanical analyses.

  2. Swimming as physical activity and recreation for women

    Directory of Open Access Journals (Sweden)

    Yfanti Maria

    2014-01-01

    Full Text Available The present study reviews all data that establish swimming as an everyday lifestyle and recreational activity for women, since it promotes wellness, well-being and longevity. Swimming as a natural, physical activity is one of the most effective ways of exercise, since it affects and work outs the whole body. It is the most suitable sport for all age groups, because it combines beneficial results, for both body and soul and is also a low-risk-injury physical exercise. Aim of this study is to record the effect of recreational swimming in physical condition indexes and in quality of life in women. In particular to record the benefits, since studies have shown that swimming can help in prevention and treatment of chronic diseases and improves quality of life, of well-being and longevity. Results of all studies showed that swimming, as a great natural recreational activity has multiple beneficial effects on the female body that are not limited to the physical characteristics but are extended to the mental ones. Challenges for the application and development fields of this particular method of exercise, are the quality of service provided and the staffing of departments and programs in multiple carriers, private or public. Researchers and writers agree that there are great prospects for growth for women through partnerships, with programs and systematic research in the field of recreational swimming.

  3. Ovarian and uterine alterations following forced swimming: An immunohistochemical study.

    Science.gov (United States)

    Seyed Saadat, Seyedeh Nazanin; Mohammadghasemi, Fahimeh; Ebrahimi, Hannan; Rafati Sajedi, Hanieh; Chatrnour, Gelayol

    2016-10-01

    Physical exercise is known to be a stressor stimulus that leads to reproductive disruption. The aim of this study was to evaluate the effect of forced swimming on the uterus and ovaries in mice. Adult mice (N=24) were divided into the following three groups: A, control; B, swimming in water (10 o C); and C, swimming in water (23 o C). Swimmers swam for 5 min daily for 5 consecutive days/ wk during 2 wks. An enzyme linked immunosorbent assay was used to determine serum estradiol, follicle stimulating hormone (FSH) and testosterone levels. Immunohistochemistry was performed to study apoptotic cells or estrogen receptor (ER) expression in uterine epithelial cells and ovaries. ANOVA was used for statistical analysis. Swimming in both groups reduced the serum FSH and estradiol levels (pForced swimming of 2 wks duration reduces the serum levels of FSH and estradiol without having effects on apoptosis in the ovaries or uteri of mice. Over a long period of time, forced swimming may have an adverse effect on fertility.

  4. Unsteady bio-fluid dynamics in flying and swimming

    Science.gov (United States)

    Liu, Hao; Kolomenskiy, Dmitry; Nakata, Toshiyuki; Li, Gen

    2017-08-01

    Flying and swimming in nature present sophisticated and exciting ventures in biomimetics, which seeks sustainable solutions and solves practical problems by emulating nature's time-tested patterns, functions, and strategies. Bio-fluids in insect and bird flight, as well as in fish swimming are highly dynamic and unsteady; however, they have been studied mostly with a focus on the phenomena associated with a body or wings moving in a steady flow. Characterized by unsteady wing flapping and body undulation, fluid-structure interactions, flexible wings and bodies, turbulent environments, and complex maneuver, bio-fluid dynamics normally have challenges associated with low Reynolds number regime and high unsteadiness in modeling and analysis of flow physics. In this article, we review and highlight recent advances in unsteady bio-fluid dynamics in terms of leading-edge vortices, passive mechanisms in flexible wings and hinges, flapping flight in unsteady environments, and micro-structured aerodynamics in flapping flight, as well as undulatory swimming, flapping-fin hydrodynamics, body-fin interaction, C-start and maneuvering, swimming in turbulence, collective swimming, and micro-structured hydrodynamics in swimming. We further give a perspective outlook on future challenges and tasks of several key issues of the field.

  5. Swimming of a Sea Butterfly with an Elongated Shell

    Science.gov (United States)

    Karakas, Ferhat; Maas, Amy E.; Murphy, David W.

    2017-11-01

    Sea butterflies (pteropods) are small, zooplanktonic marine snails which swim by flapping highly flexible parapodia. Previous studies show that the swimming hydrodynamics of Limacina helicina, a polar pteropod with a spiraled shell, is similar to tiny insect flight aerodynamics and that forward-backward pitching is key for lift generation. However, swimming by diverse pteropod species with different shell shapes has not been examined. We present measurements of the swimming of Cuvierina columnella, a warm water species with an elongated non-spiraled shell collected off the coast of Bermuda. With a body length of 9 mm, wing beat frequency of 4-6 Hz and swimming speed of 35 mm/s, these organisms swim at a Reynolds number of approximately 300, larger than that of L. helicina. High speed 3D kinematics acquired via two orthogonal cameras reveals that the elongated shell correlates with reduced body pitching and that the wings bend approximately 180 degrees in each direction, overlapping at the end of each half-stroke. Time resolved 2D flow measurements collected with a micro-PIV system reveal leading edge vortices present in both power and recovery strokes. Interactions between the overlapping wings and the shell also likely play a role in lift generation.

  6. Swimming of a Tiny Subtropical Sea Butterfly with Coiled Shell

    Science.gov (United States)

    Murphy, David; Karakas, Ferhat; Maas, Amy

    2017-11-01

    Sea butterflies, also known as pteropods, include a variety of small, zooplanktonic marine snails. Thecosomatous pteropods possess a shell and swim at low Reynolds numbers by beating their wing-like parapodia in a manner reminiscent of insect flight. In fact, previous studies of the pteropod Limacina helicina have shown that pteropod swimming hydrodynamics and tiny insect flight aerodynamics are dynamically similar. Studies of L. helicina swimming have been performed in polar (0 degrees C) and temperate conditions (12 degrees C). Here we present measurements of the swimming of Heliconoides inflatus, a smaller yet morphologically similar pteropod that lives in warm Bermuda seawater (21 degrees C) with a viscosity almost half that of the polar seawater. The collected H. inflatus have shell sizes less than 1.5 mm in diameter, beat their wings at frequencies up to 11 Hz, and swim upwards in sawtooth trajectories at speeds up to approximately 25 mm/s. Using three-dimensional wing and body kinematics collected with two orthogonal high speed cameras and time-resolved, 2D flow measurements collected with a micro-PIV system, we compare the effects of smaller body size and lower water viscosity on the flow physics underlying flapping-based swimming by pteropods and flight by tiny insects.

  7. Turtle mimetic soft robot with two swimming gaits.

    Science.gov (United States)

    Song, Sung-Hyuk; Kim, Min-Soo; Rodrigue, Hugo; Lee, Jang-Yeob; Shim, Jae-Eul; Kim, Min-Cheol; Chu, Won-Shik; Ahn, Sung-Hoon

    2016-05-04

    This paper presents a biomimetic turtle flipper actuator consisting of a shape memory alloy composite structure for implementation in a turtle-inspired autonomous underwater vehicle. Based on the analysis of the Chelonia mydas, the flipper actuator was divided into three segments containing a scaffold structure fabricated using a 3D printer. According to the filament stacking sequence of the scaffold structure in the actuator, different actuating motions can be realized and three different types of scaffold structures were proposed to replicate the motion of the different segments of the flipper of the Chelonia mydas. This flipper actuator can mimic the continuous deformation of the forelimb of Chelonia mydas which could not be realized in previous motor based robot. This actuator can also produce two distinct motions that correspond to the two different swimming gaits of the Chelonia mydas, which are the routine and vigorous swimming gaits, by changing the applied current sequence of the SMA wires embedded in the flipper actuator. The generated thrust and the swimming efficiency in each swimming gait of the flipper actuator were measured and the results show that the vigorous gait has a higher thrust but a relatively lower swimming efficiency than the routine gait. The flipper actuator was implemented in a biomimetic turtle robot, and its average swimming speed in the routine and vigorous gaits were measured with the vigorous gait being capable of reaching a maximum speed of 11.5 mm s(-1).

  8. Simulation of swimming strings immersed in a viscous fluid flow

    Science.gov (United States)

    Huang, Wei-Xi; Sung, Hyung Jin

    2006-11-01

    In nature, many phenomena involve interactions between flexible bodies and their surrounding viscous fluid, such as a swimming fish or a flapping flag. The intrinsic dynamics is complicate and not well understood. A flexible string can be regarded as a one-dimensional flag model. Many similarities can be found between the flapping string and swimming fish, although different wake speed results in a drag force for the flapping string and a propulsion force for the swimming fish. In the present study, we propose a mathematical formulation for swimming strings immersed in a viscous fluid flow. Fluid motion is governed by the Navier-Stokes equations and a momentum forcing is added in order to bring the fluid to move at the same velocity with the immersed surface. A flexible inextensible string model is described by another set of equations with an additional momentum forcing which is a result of the fluid viscosity and the pressure difference across the string. The momentum forcing is calculated by a feedback loop. Simulations of several numerical examples are carried out, including a hanging string which starts moving under gravity without ambient fluid, a swinging string immersed in a quiescent viscous fluid, a string swimming within a uniform surrounding flow, and flow over two side-by-side strings. The numerical results agree well with the theoretical analysis and previous experimental observations. Further simulation of a swimming fish is under consideration.

  9. Effect of swimming suit design on the energy demands of swimming.

    Science.gov (United States)

    Starling, R D; Costill, D L; Trappe, T A; Jozsi, A C; Trappe, S W; Goodpaster, B H

    1995-07-01

    Eight competitive male swimmers completed a standardized 365.8 m (400 yd) freestyle swimming trial at a fixed pace (approximately 90% of maximal effort) while wearing a torso swim suit (TOR) or a standard racing suit (STD). Oxygen uptake (VO2), blood lactate, heart rate (HR), and distance per stroke (DPS) measurements were obtained. In addition, a video-computer system was used to collect velocity data during a prone underwater glide following a maximal leg push-off from the side of the pool while wearing the TOR and STD suits. These data were used to calculate the total distance covered during the glides. VO2 (3.76 +/- 0.16 vs 3.92 +/- 0.18 l.min-1) and lactate (8.08 +/- 0.53 vs, 9.66 +/- 0.66 mM) were significantly (P 0.05) between the TOR (170.1 +/- 5.1 b.min-1) and STD (173.5 +/- 5.7 b.min-1) trials. DPS was significantly greater during the TOR (2.70 +/- 0.066 m.stroke-1) versus STD (2.58 +/- 0.054 m.stroke-1) trial. A significantly greater total distance was covered during the prone glide while wearing the TOR (2.05 +/- 0.067 m) compared to the STD (2.00 +/- 0.080 m) suit. These findings demonstrate that a specially designed torso suit reduces the energy demand of swimming compared to a standard racing suit which may be due to a reduction in body drag.

  10. Wave Climate and Wave Response, 2025 Plan, Kahului Harbor, Maui, Hawaii

    National Research Council Canada - National Science Library

    Thompson, Edward

    2002-01-01

    ... (wind waves and swell) and long waves (harbor oscillations), was used to evaluate the technical feasibility of three alternative modifications to the harbor, including the Kahului Commercial Harbor 2025 Master Plan...

  11. Establishing zebrafish as a novel exercise model: swimming economy, swimming-enhanced growth and muscle growth marker gene expression.

    Directory of Open Access Journals (Sweden)

    Arjan P Palstra

    Full Text Available BACKGROUND: Zebrafish has been largely accepted as a vertebrate multidisciplinary model but its usefulness as a model for exercise physiology has been hampered by the scarce knowledge on its swimming economy, optimal swimming speeds and cost of transport. Therefore, we have performed individual and group-wise swimming experiments to quantify swimming economy and to demonstrate the exercise effects on growth in adult zebrafish. METHODOLOGY/PRINCIPAL FINDINGS: Individual zebrafish (n = 10 were able to swim at a critical swimming speed (U(crit of 0.548±0.007 m s(-1 or 18.0 standard body lengths (BL s(-1. The optimal swimming speed (U(opt at which energetic efficiency is highest was 0.396±0.019 m s(-1 (13.0 BL s(-1 corresponding to 72.26±0.29% of U(crit. The cost of transport at optimal swimming speed (COT(opt was 25.23±4.03 µmol g(-1 m(-1. A group-wise experiment was conducted with zebrafish (n = 83 swimming at U(opt for 6 h day(-1 for 5 days week(-1 for 4 weeks vs. zebrafish (n = 84 that rested during this period. Swimming zebrafish increased their total body length by 5.6% and body weight by 41.1% as compared to resting fish. For the first time, a highly significant exercise-induced growth is demonstrated in adult zebrafish. Expression analysis of a set of muscle growth marker genes revealed clear regulatory roles in relation to swimming-enhanced growth for genes such as growth hormone receptor b (ghrb, insulin-like growth factor 1 receptor a (igf1ra, troponin C (stnnc, slow myosin heavy chain 1 (smyhc1, troponin I2 (tnni2, myosin heavy polypeptide 2 (myhz2 and myostatin (mstnb. CONCLUSIONS/SIGNIFICANCE: From the results of our study we can conclude that zebrafish can be used as an exercise model for enhanced growth, with implications in basic, biomedical and applied sciences, such as aquaculture.

  12. Kinematics of swimming and thrust production during powerstroking bouts of the swim frenzy in green turtle hatchlings

    Directory of Open Access Journals (Sweden)

    David T. Booth

    2014-09-01

    Full Text Available Hatchling sea turtles emerge from nests, crawl down the beach and enter the sea where they typically enter a stereotypical hyperactive swimming frenzy. During this swim the front flippers are moved up and down in a flapping motion and are the primary source of thrust production. I used high-speed video linked with simultaneous measurement of thrust production in tethered hatchlings, along with high-speed video of free swimming hatchlings swimming at different water speeds in a swim flume to investigate the links between kinematics of front flipper movement, thrust production and swimming speed. In particular I tested the hypotheses that (1 increased swimming speed is achieved through an increased stroke rate; (2 force produced per stroke is proportional to stroke amplitude, (3 that forward thrust is produced during both the down and up phases of stroking; and (4 that peak thrust is produced towards the end of the downstroke cycle. Front flipper stroke rate was independent of water speed refuting the hypothesis that swimming speed is increased by increasing stroke rate. Instead differences in swimming speed were caused by a combination of varying flipper amplitude and the proportion of time spent powerstroking. Peak thrust produced per stroke varied within and between bouts of powerstroking, and these peaks in thrust were correlated with both flipper amplitude and flipper angular momentum during the downstroke supporting the hypothesis that stroke force is a function of stroke amplitude. Two distinct thrust production patterns were identified, monophasic in which a single peak in thrust was recorded during the later stages of the downstroke, and biphasic in which a small peak in thrust was recorded at the very end of the upstroke and this followed by a large peak in thrust during the later stages of the downstroke. The biphasic cycle occurs in ∼20% of hatchlings when they first started swimming, but disappeared after one to two hours of

  13. Swimming against the tide: explaining the Higgs

    CERN Multimedia

    Emma Sanders

    2012-01-01

    "Never before in the field of science journalism have so few journalists understood what so many physicists were telling them!" tweeted the UK Channel 4’s Tom Clarke from last December’s Higgs seminar. As a consequence, most coverage focused on debates over the use of the label “god particle” and the level of excitement of the physicists (high), whilst glossing over what this excitement was actually all about.   So what is the Higgs? Something fundamental. Something to do with mass. If your interest in physics is more than simply passing, you may find that rooms full of chattering politicians or the use of different footwear when walking through snow just don’t do the job in convincing you why the Higgs is so important. And if images of fish make you feel like a fish out of water - or at least one swimming against a strong current - then perhaps you would appreciate a different approach. The need for the Higgs Whilst gauge th...

  14. Do swimming animals mix the ocean?

    Science.gov (United States)

    Dabiri, John

    2013-11-01

    Perhaps. The oceans are teeming with billions of swimming organisms, from bacteria to blue whales. Current research efforts in biological oceanography typically focus on the impact of the marine environment on the organisms within. We ask the opposite question: can organisms in the ocean, especially those that migrate vertically every day and regionally every year, change the physical structure of the water column? The answer has potentially important implications for ecological models at local scale and climate modeling at global scales. This talk will introduce the still-controversial prospect of biogenic ocean mixing, beginning with evidence from measurements in the field. More recent laboratory-scale experiments, in which we create controlled vertical migrations of plankton aggregations using laser signaling, provide initial clues toward a mechanism to achieve efficient mixing at scales larger than the individual organisms. These results are compared and contrasted with theoretical models, and they highlight promising avenues for future research in this area. Funding from the Office of Naval Research and the National Science Foundation is gratefully acknowledged.

  15. Nutrition for synchronized swimming: a review.

    Science.gov (United States)

    Lundy, Bronwen

    2011-10-01

    Synchronized swimming enjoys worldwide popularity and has been part of the formal Olympic program since 1984. Despite this, relatively little research has been conducted on participant nutrition practices and requirements, and there are significant gaps in the knowledge base despite the numerous areas in which nutrition could affect performance and safety. This review aimed to summarize current findings and identify areas requiring further research. Uniform physique in team or duet events may be more important than absolute values for muscularity or body fat, but a lean and athletic appearance remains key. Synchronized swimmers appear to have an increased risk of developing eating disorders, and there is evidence of delayed menarche, menstrual dysfunction, and lower bone density relative to population norms. Dietary practices remain relatively unknown, but micronutrient status for iron and magnesium may be compromised. More research is required across all aspects of nutrition status, anthropometry, and physiology, and both sports nutrition and sports medicine support may be required to reduce risks for participants.

  16. A Forced Damped Oscillation Framework for Undulatory Swimming Provides New Insights into How Propulsion Arises in Active and Passive Swimming

    Science.gov (United States)

    Bhalla, Amneet Pal Singh; Griffith, Boyce E.; Patankar, Neelesh A.

    2013-01-01

    A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions (“active” swimming) or by forces imparted by the surrounding fluid (“passive” swimming), is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD) simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained. PMID:23785272

  17. A forced damped oscillation framework for undulatory swimming provides new insights into how propulsion arises in active and passive swimming.

    Science.gov (United States)

    Bhalla, Amneet Pal Singh; Griffith, Boyce E; Patankar, Neelesh A

    2013-01-01

    A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions ("active" swimming) or by forces imparted by the surrounding fluid ("passive" swimming), is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD) simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained.

  18. A forced damped oscillation framework for undulatory swimming provides new insights into how propulsion arises in active and passive swimming.

    Directory of Open Access Journals (Sweden)

    Amneet Pal Singh Bhalla

    Full Text Available A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions ("active" swimming or by forces imparted by the surrounding fluid ("passive" swimming, is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained.

  19. Benefits and Enjoyment of a Swimming Intervention for Youth With Cerebral Palsy: An RCT Study.

    Science.gov (United States)

    Declerck, Marlies; Verheul, Martine; Daly, Daniel; Sanders, Ross

    2016-01-01

    To investigate enjoyment and specific benefits of a swimming intervention for youth with cerebral palsy (CP). Fourteen youth with CP (aged 7 to 17 years, Gross Motor Function Classification System levels I to III) were randomly assigned to control and swimming groups. Walking ability, swimming skills, fatigue, and pain were assessed at baseline, after a 10-week swimming intervention (2/week, 40-50 minutes) or control period, after a 5-week follow-up and, for the intervention group, after a 20-week follow-up period. The level of enjoyment of each swim-session was assessed. Levels of enjoyment were high. Walking and swimming skills improved significantly more in the swimming than in the control group (P = .043; P = .002, respectively), whereas fatigue and pain did not increase. After 20 weeks, gains in walking and swimming skills were retained (P = .017; P = .016, respectively). We recommend a swimming program for youth with CP to complement a physical therapy program.

  20. Swimming with multiple propulsors: measurement and comparison of swimming gaits in three species of neotropical cichlids.

    Science.gov (United States)

    Feilich, Kara L

    2017-11-15

    Comparative studies of fish swimming have been limited by the lack of quantitative definitions of fish gaits. Traditionally, steady swimming gaits have been defined categorically by the fin or region of the body that is used as the main propulsor and named after major fish clades (e.g. carangiform, anguilliform, balistiform, labriform). This method of categorization is limited by the lack of explicit measurements, the inability to incorporate contributions of multiple propulsors and the inability to compare gaits across different categories. I propose an alternative framework for the definition and comparison of fish gaits based on the propulsive contribution of each structure (body and/or fin) being used as a propulsor relative to locomotor output, and demonstrate the effectiveness of this framework by comparing three species of neotropical cichlids with different body shapes. This approach is modular with respect to the number of propulsors considered, flexible with respect to the definition of the propulsive inputs and the locomotor output of interest, and designed explicitly to handle combinations of propulsors. Using this approach, gait can be defined as a trajectory through propulsive space, and gait transitions can be defined as discontinuities in the gait trajectory. By measuring and defining gait in this way, patterns of clustering corresponding to existing categorical definitions of gait may emerge, and gaits can be rigorously compared across categories. © 2017. Published by The Company of Biologists Ltd.

  1. Breaking the Myth That Relay Swimming Is Faster Than Individual Swimming.

    Science.gov (United States)

    Skorski, Sabrina; Etxebarria, Naroa; Thompson, Kevin G

    2016-04-01

    To investigate if swimming performance is better in a relay race than in the corresponding individual race. The authors analyzed 166 elite male swimmers from 15 nations in the same competition (downloaded from www.swimrankings.net). Of 778 observed races, 144 were Olympic Games performances (2000, 2004, 2012), with the remaining 634 performed in national or international competitions. The races were 100-m (n = 436) and 200-m (n = 342) freestyle events. Relay performance times for the 2nd-4th swimmers were adjusted (+ 0.73 s) to allow for the "flying start." Without any adjustment, mean individual relay performances were significantly faster for the first 50 m and overall time in the 100-m events. Furthermore, the first 100 m of the 200-m relay was significantly faster (P > .001). During relays, swimmers competing in 1st position did not show any difference compared with their corresponding individual performance (P > .16). However, swimmers competing in 2nd-4th relay-team positions demonstrated significantly faster times in the 100-m (P individual events (P team positions were adjusted for the flying start no differences were detected between relay and individual race performance for any event or split time (P > .17). Highly trained swimmers do not swim (or turn) faster in relay events than in their individual races. Relay exchange times account for the difference observed in individual vs relay performance.

  2. [Swimming, physical activity and health: a historical perspective].

    Science.gov (United States)

    Conti, A A

    2015-01-01

    Swimming, which is the coordinated and harmonic movement of the human body inside a liquid medium by means of the combined action of the superior and inferior limbs, is a physical activity which is diffused throughout the whole world and it is practiced by healthy and non-healthy subjects. Swimming is one of the physical activities with less contraindications and, with limited exceptions, can be suggested to individuals of both sexes and of every age range, including the most advanced. Swimming requires energy both for the floating process and for the anterograde progression, with a different and variable osteo-arthro-muscular involvement according to the different styles. The energetic requirement is about four times that for running, with an overall efficiency inferior to 10%; the energetic cost of swimming in the female subject is approximately two thirds of that in the male subject. The moderate aerobic training typical of swimming is useful for diabetic and hypertensive individuals, for people with painful conditions of rachis, as also for obese and orthopaedic patients. Motor activity inside the water reduces the risk of muscular-tendinous lesions and, without loading the joints in excess, requires the harmonic activation of the whole human musculature. Swimming is an activity requiring multiple abilities, ranging from a sense of equilibrium to that of rhythm, from reaction speed to velocity, from joint mobility to resistance. The structured interest for swimming in the perspective of human health from the beginning of civilization, as described in this contribution, underlines the relevance attributed to this activity in the course of human history.

  3. Bar Harbor, ME Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Bar Harbor, Maine Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST) model. MOST...

  4. Hydrocarbon pollutants shape bacterial community assembly of harbor sediments

    KAUST Repository

    Barbato, Marta; Mapelli, Francesca; Magagnini, Mirko; Chouaia, Bessem; Armeni, Monica; Marasco, Ramona; Crotti, Elena; Daffonchio, Daniele; Borin, Sara

    2016-01-01

    Petroleum pollution results in co-contamination by different classes of molecules, entailing the occurrence of marine sediments difficult to remediate, as in the case of the Ancona harbor (Mediterranean Sea, Italy). Autochthonous bioaugmentation

  5. Extrachromosomal deoxyribonucleic acid in R factor-harboring Enterobacteriaceae

    DEFF Research Database (Denmark)

    Møller, JK; Bak, AL; Christiansen, C

    1976-01-01

    Extrachromosomal deoxyribonucleic acid (DNA) from 24 different R factor-harboring Enterobacteriaceae was isolated and characterized by analytical ultracentrifugation and electron microscopy. The R factors represented 15 different patterns of transferable drug resistance found in enterobacteria from...

  6. 75 FR 76613 - National Pearl Harbor Remembrance Day, 2010

    Science.gov (United States)

    2010-12-09

    .... The deadly attack on Pearl Harbor did not accomplish its mission of breaking the American spirit..., aiding the war effort by working in manufacturing plants, participating in rationing programs, or...

  7. Apra Harbor, Guam Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Apra Harbor, Guam Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST) model. MOST...

  8. Pearl Harbor, Hawaii 1 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1/3-second Pearl Harbor Hawaii Elevation Grid provides bathymetric data in ASCII raster format of 1/3-second resolution in geographic coordinates. This grid is...

  9. Submarine Biofouling Control- Chlorination DATS Study at Pearl Harbor

    National Research Council Canada - National Science Library

    Wegand, John

    2001-01-01

    The intent of this document is to sumarize the chlorination studies performed at Naval Station, Pearl Harbor in support of biofouling control initiatives for the submarine community, as requested by NAVSEA 92T...

  10. Ground-water status report, Pearl Harbor area, Hawaii, 1978

    Science.gov (United States)

    Soroos, Ronald L.; Ewart, Charles J.

    1979-01-01

    Increasing demand for freshwater in Hawaii has placed heavy stress on many of the State 's basal aquifer systems. The most heavily stressed of these systems is the Pearl Harbor on Oahu. The Pearl Harbor basal aquifer supplies as much as 277 million gallons per day. Since early in this century, spring discharge has been declining while pumpage has been increasing. Total ground-water discharge has remained steady despite short-term fluctuations. Some wells show general increases in chloride concentration while others remain steady. Chloride concentrations throughout the area show no apparent increase since 1970. Basal water head maps of the Pearl Harbor area clearly reflect the natural discharge points, which are the springs located along the shore near the center of Pearl Harbor. Basal-water hydrographs show a general decline of about 0.09 foot per year. This implies depletion of storage at a rate of about 25 million gallons per day. (USGS).

  11. Pearl Harbor, Hawaii Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Pearl Harbor, Hawaii Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST) model....

  12. Harbor seal vibrissa morphology suppresses vortex-induced vibrations

    OpenAIRE

    Hanke, Wolf; Witte, Mathias; Miersch, Lars; Brede, Martin; Oeffner, Johannes; Michael, Mark; Hanke, Frederike; Leder, Alfred; Dehnhardt, Guido

    2010-01-01

    Harbor seals (Phoca vitulina) often live in dark and turbid waters, where their mystacial vibrissae, or whiskers, play an important role in orientation. Besides detecting and discriminating objects by direct touch, harbor seals use their whiskers to analyze water movements, for example those generated by prey fish or by conspecifics. Even the weak water movements left behind by objects that have passed by earlier can be sensed and followed accurately (hydrodynamic trail following). While scan...

  13. Satellite Monitoring of Boston Harbor Water Quality: Initial Investigations

    Science.gov (United States)

    Sheldon, P.; Chen, R. F.; Schaaf, C.; Pahlevan, N.; Lee, Z.

    2016-02-01

    The transformation of Boston Harbor from the "dirtiest in America" to a National Park Area is one of the most remarkable estuarine recoveries in the world. A long-term water quality dataset from 1991 to present exists in Boston Harbor due to a $3. 8 billion lawsuit requiring the harbor clean-up. This project uses discrete water sampling and underway transects with a towed vehicle coordinated with Landsat 7 and Landsat 8 to create surface maps of chlorophyll a (Chl a), dissolved organic matter (CDOM and DOC), total suspended solids (TSS), diffuse attenuation coefficient (Kd_490), and photic depth in Boston Harbor. In addition, 3 buoys have been designed, constructed, and deployed in Boston Harbor that measure Chl a and CDOM fluorescence, optical backscatter, salinity, temperature, and meteorological parameters. We are initially using summer and fall of 2015 to develop atmospheric corrections for conditions in Boston Harbor and develop algorithms for Landsat 8 data to estimate in water photic depth, TSS, Chl a, Kd_490, and CDOM. We will report on initial buoy and cruise data and show 2015 Landsat-derived distributions of water quality parameters. It is our hope that once algorithms for present Landsat imagery can be developed, historical maps of water quality can be constructed using in water data back to 1991.

  14. Impaired swim bladder inflation in early-life stage fathead ...

    Science.gov (United States)

    The present study investigated whether inhibition of deiodinase, the enzyme which converts thyroxine (T4) to the more biologically-active form, 3,5,3'-triiodothyronine (T3), would impact inflation of the posterior and/or anterior chamber of the swim bladder, processes previously demonstrated to be thyroid-hormone regulated. Two experiments were conducted using a model deiodinase inhibitor, iopanoic acid (IOP). In the first study, fathead minnow (Pimephales promelas) embryos were exposed to 0.6, 1.9, or 6.0 mg IOP/L or control water in a flow-through system until reaching 6 days post-fertilization (dpf) at which time posterior swim bladder inflation was assessed. To examine effects on anterior swim bladder inflation, a second study was conducted with 6 dpf larvae exposed to the same IOP concentrations until reaching 21 dpf. Fish from both studies were sampled for T4/T3 measurements, gene transcription analyses, and thyroid histopathology. In the embryo study, incidence and length of inflated posterior swim bladders were significantly reduced in the 6.0 mg/L treatment at 6 dpf. Incidence of inflation and length of anterior swim bladder in larval fish were significantly reduced in all IOP treatments at 14 dpf, but inflation recovered by 18 dpf. Throughout the larval study, whole body T4 concentrations were significantly increased and T3 concentrations were significantly decreased in all IOP treatments. Consistent with hypothesized compensatory responses, sig

  15. Muscle Activity during Dryland Swimming while Wearing a Triathlon Wetsuit

    Directory of Open Access Journals (Sweden)

    Ciro Agnelli

    2018-01-01

    Full Text Available Background: Triathletes typically wear a wetsuit during the swim portion of an event, but it is not clear if muscle activity is influenced by wearing a wetsuit. Purpose: To investigate if shoulder muscle activity was influenced by wearing a full-sleeve wetsuit vs. no wetsuit during dryland swimming. Methods: Participants (n=10 males; 179.1±13.2 cm; 91.2±7.25 kg; 45.6±10.5 years completed two dry land swimming conditions on a swim ergometer: No Wetsuit (NW and with Wetsuit (W. Electromyography (EMG of four upper extremity muscles was recorded (Noraxon telemetry EMG, 500 Hz during each condition: Trapezius (TRAP, Triceps (TRI, Anterior Deltoid (AD and Posterior Deltoid (PD. Each condition lasted 90 seconds with data collected during the last 60 seconds. Resistance setting was self-selected and remained constant for both conditions. Stroke rate was controlled at 60 strokes per minute by having participants match a metronome. Average (AVG and Root Mean Square (RMS EMG were calculated over 45 seconds and each were compared between conditions using a paired t-test (α=0.05 for each muscle. Results: PD and AD AVG and RMS EMG were each greater (on average 40.0% and 66.8% greater, respectively during W vs. NW (p0.05. Conclusion: The greater PD and AD muscle activity while wearing a wetsuit might affect swimming performance and /or stroke technique on long distance event.

  16. On the swimming motion of spheroidal magnetotactic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Cui Zhen; Kong Dali; Zhang Keke [Department of Mathematical Sciences, University of Exeter, Exeter EX4 4QF (United Kingdom); Pan Yongxin, E-mail: kzhang@ex.ac.uk [Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing (China)

    2012-10-15

    We investigate, via both theoretical and experimental methods, the swimming motion of magnetotactic bacteria having the shape of an elongated prolate spheroid in a viscous liquid under the influence of an imposed magnetic field. A fully three-dimensional Stokes flow, driven by the translation and rotation of a swimming bacterium, exerts a complicated viscous drag/torque on the motion of a non-spherical bacterium. By assuming that the body of the bacterium is non-deformable and that the interaction between different bacteria is weak and hence negligible, we have derived a system of 12 coupled nonlinear ordinary differential equations that govern both the motion and the orientation of a swimming spheroidal magnetotactic bacterium. The focus of the study is on how the shape of a non-spherical magnetotactic bacterium, marked by the size of its eccentricity, affects the pattern of its swimming motion. It is revealed that the pattern/speed of a swimming spheroidal magnetotactic bacterium is highly sensitive not only to the direction of its magnetic moment but also to its shape. We also compare the theoretical pattern obtained from the solutions of the 12 coupled differential equations with that observed in the laboratory experiments using the magnetotactic bacteria found in Lake Miyun near Beijing, China, showing that the observed pattern can be largely reproduced with an appropriate set of parameters in our theoretical model. (paper)

  17. Swimming mechanics and propulsive efficiency in the chambered nautilus

    Science.gov (United States)

    Neil, Thomas R.; Askew, Graham N.

    2018-02-01

    The chambered nautilus (Nautilus pompilius) encounters severe environmental hypoxia during diurnal vertical movements in the ocean. The metabolic cost of locomotion (Cmet) and swimming performance depend on how efficiently momentum is imparted to the water and how long on-board oxygen stores last. While propulsive efficiency is generally thought to be relatively low in jet propelled animals, the low Cmet in Nautilus indicates that this is not the case. We measured the wake structure in Nautilus during jet propulsion swimming, to determine their propulsive efficiency. Animals swam with either an anterior-first or posterior-first orientation. With increasing swimming speed, whole cycle propulsive efficiency increased during posterior-first swimming but decreased during anterior-first swimming, reaching a maximum of 0.76. The highest propulsive efficiencies were achieved by using an asymmetrical contractile cycle in which the fluid ejection phase was relatively longer than the refilling phase, reducing the volume flow rate of the ejected fluid. Our results demonstrate that a relatively high whole cycle propulsive efficiency underlies the low Cmet in Nautilus, representing a strategy to reduce the metabolic demands in an animal that spends a significant part of its daily life in a hypoxic environment.

  18. Study on water evaporation rate from indoor swimming pools

    Directory of Open Access Journals (Sweden)

    Rzeźnik Ilona

    2017-01-01

    Full Text Available The air relative humidity in closed spaces of indoor swimming pools influences significantly on users thermal comfort and the stability of the building structure, so its preservation on suitable level is very important. For this purpose, buildings are equipped with HVAC systems which provide adequate level of humidity. The selection of devices and their technical parameters is made using the mathematical models of water evaporation rate in the unoccupied and occupied indoor swimming pool. In the literature, there are many papers describing this phenomena but the results differ from each other. The aim of the study was the experimental verification of published models of evaporation rate in the pool. The tests carried out on a laboratory scale, using model of indoor swimming pool, measuring 99cm/68cm/22cm. The model was equipped with water spray installation with six nozzles to simulate conditions during the use of the swimming pool. The measurements were made for conditions of sports pools (water temperature 24°C and recreational swimming pool (water temperature 34°C. According to the recommendations the air temperature was about 2°C higher than water temperature, and the relative humidity ranged from 40% to 55%. Models Shah and Biasin & Krumm were characterized by the best fit to the results of measurements on a laboratory scale.

  19. On the swimming motion of spheroidal magnetotactic bacteria

    International Nuclear Information System (INIS)

    Cui Zhen; Kong Dali; Zhang Keke; Pan Yongxin

    2012-01-01

    We investigate, via both theoretical and experimental methods, the swimming motion of magnetotactic bacteria having the shape of an elongated prolate spheroid in a viscous liquid under the influence of an imposed magnetic field. A fully three-dimensional Stokes flow, driven by the translation and rotation of a swimming bacterium, exerts a complicated viscous drag/torque on the motion of a non-spherical bacterium. By assuming that the body of the bacterium is non-deformable and that the interaction between different bacteria is weak and hence negligible, we have derived a system of 12 coupled nonlinear ordinary differential equations that govern both the motion and the orientation of a swimming spheroidal magnetotactic bacterium. The focus of the study is on how the shape of a non-spherical magnetotactic bacterium, marked by the size of its eccentricity, affects the pattern of its swimming motion. It is revealed that the pattern/speed of a swimming spheroidal magnetotactic bacterium is highly sensitive not only to the direction of its magnetic moment but also to its shape. We also compare the theoretical pattern obtained from the solutions of the 12 coupled differential equations with that observed in the laboratory experiments using the magnetotactic bacteria found in Lake Miyun near Beijing, China, showing that the observed pattern can be largely reproduced with an appropriate set of parameters in our theoretical model. (paper)

  20. Energetics of swimming by the ferret: consequences of forelimb paddling.

    Science.gov (United States)

    Fish, Frank E; Baudinette, Russell V

    2008-06-01

    The domestic ferret (Mustela putorius furo) swims by alternate strokes of the forelimbs. This pectoral paddling is rare among semi-aquatic mammals. The energetic implications of swimming by pectoral paddling were examined by kinematic analysis and measurement of oxygen consumption. Ferrets maintained a constant stroke frequency, but increased swimming speed by increasing stroke amplitude. The ratio of swimming velocity to foot stroke velocity was low, indicating a low propulsive efficiency. Metabolic rate increased linearly with increasing speed. The cost of transport decreased with increasing swimming speed to a minimum of 3.59+/-0.28 J N(-1) m(-1) at U=0.44 m s(-1). The minimum cost of transport for the ferret was greater than values for semi-aquatic mammals using hind limb paddling, but lower than the minimum cost of transport for the closely related quadrupedally paddling mink. Differences in energetic performance may be due to the amount of muscle recruited for propulsion and the interrelationship hydrodynamic drag and interference between flow over the body surface and flow induced by propulsive appendages.

  1. Just Keep Swimming: Neuroendocrine, Metabolic, and Behavioral Changes After a Forced Swimming Test in Zebrafish.

    Science.gov (United States)

    da Rosa, João Gabriel Santos; Barcellos, Heloísa Helena de Alcântara; Idalencio, Renan; Marqueze, Alessandra; Fagundes, Michele; Rossini, Mainara; Variani, Cristiane; Balbinoti, Francine; Tietböhl, Tássia Michele Huff; Rosemberg, Denis Broock; Barcellos, Leonardo José Gil

    2017-02-01

    In this study, we show that an adaptation of the spinning test can be used as a model to study the exercise-exhaustion-recovery paradigm in fish. This forced swimming test promotes a wide range of changes in the hypothalamus-pituitary-interrenal axis functioning, intermediary metabolism, as well in fish behavior at both exercise and recovery periods. Our results pointed that this adapted spinning test can be considered a valuable tool for evaluating drugs and contaminant effects on exercised fish. This can be a suitable protocol both to environmental-to evaluate contaminants that act in fish energy mobilization and recovery after stressors-and translational perspectives-effects of drugs on exercised or stressed humans.

  2. The role of students’ self-confidence in relation with swimming routines, frequency, and tutor in swimming class

    Science.gov (United States)

    Hartoto, S.; Khory, F. D.; Prakoso, B. B.

    2018-01-01

    It is compulsory for prospective physical education teachers to have the ability to perform swimming. The average of students’ passing in swimming class has reached 72%. Most students who failed to pass the class are those who have had aquaphobia, the condition in which one failed to perceive a situation in a positive and objective, some of which are hard to detect. This perception may come from past experience and it could diminish students’ confidence. Furthermore, the lack of confidence in students may cause unsatisfactory learning results. Therefore it is critical for the teachers to have a comprehensive knowledge of their students’ past experience in formulating a lesson. This research used descriptive qualitative approach. The aim of this article is to investigate the correlation between students’ confidence level and swimming routines, frequency, and tutors in order to succeed swimming class. This article will attempt to describe the results of a research conducted to 139 students of Department of Sport Education Universitas Negeri Surabaya as prospective physical education teachers in Indonesia who took swimming class. Past experience and confidence level are measured by a questionnaire. The results of the research show that students who have a higher level of confidence are those who follow practice routines with adequate frequency and helped by a compatible tutor.

  3. THE IMPACT OF TECHNICAL ABILITY TO SWIMMING PERFORMANCE OF THE MIXED SWIMMING AT 100m IN COLLEGE FASTO

    Directory of Open Access Journals (Sweden)

    Elvira Beganović

    2011-08-01

    Full Text Available The aim of this study was to determine the impact of technical ability to swim (the starting point, the techniques and turns, within each of these techniques of swimming (freestyle, backstroke, breaststroke and butterfly marked as input or predictor variables, the performance of mixed swimming in the 100m, marked as output or criterion variable. The study was conducted on a sample of 31 students, females, aged from 20-24 years, with the help of the testing (assessment, technical skills of swimming (start, the techniques and turns: OCJKSTR, OCJKTEH, OCJKOKR, OCJLSTR, OCJLTEH, OCJLOKR, OCJPSTR, OCJPTEH, OCJPOKR, OCJDSTR, OCJDTEH, OCJDOKR and mixed swimming in the 100m (OCJPM100, the following order: butterfly, back, breaststroke, freestyle. Analyzing the presented results of regression analysis can be stated that after testing (assessment of all predictor system statistically the most significant impact on the criterion variable had the following variables: assessment techniques freestyle (OCJKTEH, evaluation of starting breast stroke (OCJPSTR and assessment of breast stroke turns (OCJPOKR.

  4. Analytical insights into optimality and resonance in fish swimming

    Science.gov (United States)

    Kohannim, Saba; Iwasaki, Tetsuya

    2014-01-01

    This paper provides analytical insights into the hypothesis that fish exploit resonance to reduce the mechanical cost of swimming. A simple body–fluid fish model, representing carangiform locomotion, is developed. Steady swimming at various speeds is analysed using optimal gait theory by minimizing bending moment over tail movements and stiffness, and the results are shown to match with data from observed swimming. Our analysis indicates the following: thrust–drag balance leads to the Strouhal number being predetermined based on the drag coefficient and the ratio of wetted body area to cross-sectional area of accelerated fluid. Muscle tension is reduced when undulation frequency matches resonance frequency, which maximizes the ratio of tail-tip velocity to bending moment. Finally, hydrodynamic resonance determines tail-beat frequency, whereas muscle stiffness is actively adjusted, so that overall body–fluid resonance is exploited. PMID:24430125

  5. The prediction of swimming performance in competition from behavioral information.

    Science.gov (United States)

    Rushall, B S; Leet, D

    1979-06-01

    The swimming performances of the Canadian Team at the 1976 Olympic Games were categorized as being improved or worse than previous best times in the events contested. The two groups had been previously assessed on the Psychological Inventories for Competitive Swimmers. A stepwise multiple-discriminant analysis of the inventory responses revealed that 13 test questions produced a perfect discrimination of group membership. The resultant discriminant functions for predicting performance classification were applied to the test responses of 157 swimmers at the 1977 Canadian Winter National Swimming Championships. Using the same performance classification criteria the accuracy of prediction was not better than chance in three of four sex by performance classifications. This yielded a failure to locate a set of behavioral factors which determine swimming performance improvements in elite competitive circumstances. The possibility of sets of factors which do not discriminate between performances in similar environments or between similar groups of swimmers was raised.

  6. Swimming performance of the small characin Bryconamericus stramineus (Characiformes: Characidae

    Directory of Open Access Journals (Sweden)

    Miriam A. de Castro

    2010-01-01

    Full Text Available Very little research has been conducted on the swimming capacity of Neotropical fish. The few studies available have focused on large migratory species. The present study used fixed and increasing velocity tests to determine prolonged and sustained speeds of the "pequira", Bryconamericus stramineus Eigenmann, 1908, a small, abundant species found in fish passages implemented at the Paraná basin, Brazil. The results of increasing velocity tests showed significant relationships between critical speeds, total and standard lengths, and body weight. When compared with other Neotropical fish, the "pequira" is able to swim faster than individuals of other species of similar length. The point of change from sustained to prolonged swimming was found to occur at an approximate speed of 8.7 lengths per second. These data provide guidance and criteria for design and proper maintenance of structures such as fishways, fish screens and other systems that aim to facilitate or avoid upstream passages as part of management strategies.

  7. Further evidence for conditioned taste aversion induced by forced swimming.

    Science.gov (United States)

    Masaki, Takahisa; Nakajima, Sadahiko

    2005-01-31

    A series of experiments with rats reported that aversion to a taste solution can be established by forced swimming in a water pool. Experiment 1 demonstrated that correlation of taste and swimming is a critical factor for this phenomenon, indicating associative (i.e., Pavlovian) nature of this learning. Experiment 2 showed that this learning obeys the Pavlovian law of strength, by displaying a positive relationship between the duration of water immersion in training and the taste aversion observed in subsequent testing. Experiment 3 revealed that swimming rather than being wet is the critical agent, because a water shower did not endow rats with taste aversion. Experiment 4 found that taste aversion was a positive function of water level of the pools in training (0, 12 or 32 cm). These results, taken together, suggest that energy expenditure caused by physical exercise might be involved in the development of taste aversion.

  8. Is Swimming Safe in Heart Failure? A Systematic Review.

    Science.gov (United States)

    Shah, Parin; Pellicori, Pierpaolo; Macnamara, Alexandra; Urbinati, Alessia; Clark, Andrew L

    It is not clear whether swimming is safe in patients with chronic heart failure. Ten studies examining the hemodynamic effects of acute water immersion (WI) (155 patients; average age 60 years; 86% male; mean left ventricular ejection fraction (LVEF) 29%) and 6 randomized controlled trials of rehabilitation comparing swimming with either medical treatment only (n = 3) or cycling (n = 1) or aerobic exercise (n = 2), (136 patients, average age 59 years; 84% male, mean LVEF 31%) were considered. In 7 studies of warm WI (30-35°C): heart rate (HR) fell (2% to -15%), and both cardiac output (CO) (7-37%) and stroke volume (SV) increased (13-41%). In 1 study of hot WI (41°C), systemic vascular resistance (SVR) fell (41%) and HR increased (33%). In 2 studies of cold WI (12-22°C), there were no consistent effects on HR and CO. Compared with medical management, swimming led to a greater increase in peak VO2 (7-14%) and 6 minute walk test (6MWT) (7-13%). Compared with cycle training, combined swimming and cycle training led to a greater reduction in resting HR (16%), a greater increase in resting SV (23%) and SVR (15%), but no changes in resting CO and a lesser increase in peak VO2 (6%). Compared with aerobic training, combined swimming and aerobic training lead to a reduction in resting HR (19%) and SVR (54%) and a greater increase in SV (34%), resting CO (28%), LVEF (9%), and 6MWT (70%). Although swimming appears to be safe, the studies conducted have been small, very heterogeneous, and inconclusive.

  9. Mechanics of undulatory swimming in a frictional fluid.

    Science.gov (United States)

    Ding, Yang; Sharpe, Sarah S; Masse, Andrew; Goldman, Daniel I

    2012-01-01

    The sandfish lizard (Scincus scincus) swims within granular media (sand) using axial body undulations to propel itself without the use of limbs. In previous work we predicted average swimming speed by developing a numerical simulation that incorporated experimentally measured biological kinematics into a multibody sandfish model. The model was coupled to an experimentally validated soft sphere discrete element method simulation of the granular medium. In this paper, we use the simulation to study the detailed mechanics of undulatory swimming in a "granular frictional fluid" and compare the predictions to our previously developed resistive force theory (RFT) which models sand-swimming using empirically determined granular drag laws. The simulation reveals that the forward speed of the center of mass (CoM) oscillates about its average speed in antiphase with head drag. The coupling between overall body motion and body deformation results in a non-trivial pattern in the magnitude of lateral displacement of the segments along the body. The actuator torque and segment power are maximal near the center of the body and decrease to zero toward the head and the tail. Approximately 30% of the net swimming power is dissipated in head drag. The power consumption is proportional to the frequency in the biologically relevant range, which confirms that frictional forces dominate during sand-swimming by the sandfish. Comparison of the segmental forces measured in simulation with the force on a laterally oscillating rod reveals that a granular hysteresis effect causes the overestimation of the body thrust forces in the RFT. Our models provide detailed testable predictions for biological locomotion in a granular environment.

  10. Do swimming goggles limit microbial contamination of contact lenses?

    Science.gov (United States)

    Wu, Yvonne T; Tran, Jess; Truong, Michelle; Harmis, Najat; Zhu, Hua; Stapleton, Fiona

    2011-04-01

    Wearing goggles over contact lenses while swimming is often recommended by eye care professionals. Limited data are available to assess this recommendation. The purpose of this study was to examine whether wearing goggles while swimming limits bacterial colonization on contact lenses and whether the type of lens worn affects contamination rates. Twenty-three subjects underwent two swimming sessions at an ocean (salt water) pool (Maroubra beach Rock Pool, Sydney, Australia). Silicone hydrogel (Ciba Focus Night and Day) or hydrogel lenses (Ciba Focus Daily) were inserted into subjects' eyes before 30 min of swimming sessions, and subjects used modified goggles to mimic goggled and non-goggled conditions. At the end of each session, lenses were collected for microbial investigation. Viable bacterial colonies were classified as gram positive and gram negative and enumerated. The level of bacterial colonization on contact lenses between goggled and non-goggled conditions and between the two lens materials were compared. The range of colony forming units recovered from goggled lenses were 0 to 930 compared with 0 to 1210 on non-goggled lenses. The majority of subjects (16/23) had more microorganisms in the non-goggled condition than when wearing goggles (p = 0.03). Gram negative organisms were found in three non-goggled lenses. No significant difference was shown in the number of bacteria isolated from silicone hydrogel and hydrogel lenses (p > 0.6) irrespective of wearing goggles. Water samples had consistently higher numbers of bacterial counts than those adhered to the lenses; however, no association was found between the number of bacteria in the water sample and those found on the contact lenses. Consistently, fewer bacterial colonies were found on the goggled contact lens, thus suggesting goggles offer some protection against bacterial colonization of contact lenses while swimming. These data would support the recommendation encouraging lens wearers to use goggles

  11. The Fastskin Revolution From Human Fish to Swimming Androids

    Directory of Open Access Journals (Sweden)

    Jennifer Craik

    2011-04-01

    Full Text Available The story of fastskin swimsuits reflects some of the challenges facing the impact of technology in postmodern culture. Introduced in 1999 and ratified for the Sydney 2000 Olympic Games, fastskin swimsuits were touted as revolutionising competitive swimming. Ten years later, they were banned by the world’s swimming regulatory body FINA (the Fédération Internationale de Natation, with the ban taking effect from January 2010 (Shipley 2009. The reason was the controversy caused by the large number of world records that were broken by competitors wearing polyurethane swimsuits, the next generation of the original fast skin suits. These suits were deemed to be providing an artificial advantage by increasing buoyancy and reducing drag. This had been an issue ever since they were introduced, yet FINA had approved the suits and, thereby, unleashed an unstoppable technological revolution of the sport of competitive swimming. Underlying this was the issue about its implications of the transformation of a sport based on the movement of the human body through water without the aid of artificial devices or apparatus. This article argues that the advent of the fastskin has not only transformed the art of swimming but has created a new image of the swimmer as a virtual android rather than a human fish. In turn, the image of the sport of swimming has been re-mapped as a technical artefact and sci-fi spectacle based on a radically transformed concept of the swimming body as a material object that has implications for the ideal of the fashionable body.

  12. Warm-up and performance in competitive swimming.

    Science.gov (United States)

    Neiva, Henrique P; Marques, Mário C; Barbosa, Tiago M; Izquierdo, Mikel; Marinho, Daniel A

    2014-03-01

    Warm-up before physical activity is commonly accepted to be fundamental, and any priming practices are usually thought to optimize performance. However, specifically in swimming, studies on the effects of warm-up are scarce, which may be due to the swimming pool environment, which has a high temperature and humidity, and to the complexity of warm-up procedures. The purpose of this study is to review and summarize the different studies on how warming up affects swimming performance, and to develop recommendations for improving the efficiency of warm-up before competition. Most of the main proposed effects of warm-up, such as elevated core and muscular temperatures, increased blood flow and oxygen delivery to muscle cells and higher efficiency of muscle contractions, support the hypothesis that warm-up enhances performance. However, while many researchers have reported improvements in performance after warm-up, others have found no benefits to warm-up. This lack of consensus emphasizes the need to evaluate the real effects of warm-up and optimize its design. Little is known about the effectiveness of warm-up in competitive swimming, and the variety of warm-up methods and swimming events studied makes it difficult to compare the published conclusions about the role of warm-up in swimming. Recent findings have shown that warm-up has a positive effect on the swimmer's performance, especially for distances greater than 200 m. We recommend that swimmers warm-up for a relatively moderate distance (between 1,000 and 1,500 m) with a proper intensity (a brief approach to race pace velocity) and recovery time sufficient to prevent the early onset of fatigue and to allow the restoration of energy reserves (8-20 min).

  13. Tech Talk for Social Studies Teachers Lest We Forget: Remembering Pearl Harbor.

    Science.gov (United States)

    Green, Tim

    2001-01-01

    Presents an annotated bibliography that provides Web sites about Pearl Harbor (Hawaii). Includes Web sites that cover Pearl Harbor history, a live view of Pearl Harbor, stories from people who remember where they were during the attack, information on the naval station at Pearl Harbor, and a virtual tour of the USS Arizona. (CMK)

  14. Operation and Maintence, Vermilion Harbor, Erie County, Ohio.

    Science.gov (United States)

    1976-03-01

    Aphanozomenon flos- aguae . The Ohio EPA reports that on a yearly average, Cyclotella, Stephanodiscus and pennate diatoms are predominant, particularly during the...for both recre- ational and potable water uses (71). For recreational uses (swimming, boating, skiing, etc.), the number of total coliforms per 100 ml

  15. Feasibility of Serial Saliva Collection for Surveillance of Swimming-Associated Illness

    Science.gov (United States)

    BACKGROUND. The symptoms of many swimming-associated illnesses overlap, and clinical diagnoses often require serum or stool samples. Therefore, it has been difficult to determine the contributions of different etiologic agents to swimming-associated illness. OBJECTIVES. We collec...

  16. Swimming pool attendance and respiratory symptoms and allergies among Dutch children

    NARCIS (Netherlands)

    Jacobs, J.H.; Fuertes, E.; Krop, E.J.M.; Spithoven, J.; Tromp, P.; Heederik, D.J.J.

    2012-01-01

    OBJECTIVES To describe associations among swimming, respiratory health, allergen sensitisation and Clara cell protein 16 (CC16) levels in Dutch schoolchildren. Trichloramine levels in swimming pool air were determined to assess potential exposure levels. METHODS Respiratory health and pool

  17. DEVELOPMENT OF EXPOSURE-RESPONSE RELATIONSHIPS BETWEEN INDICATORS OF WATER QUALITY AND SWIMMING-ASSOCIATED ILLNESS

    Science.gov (United States)

    Exposure to contaminated water during recreational swimming has long been associated with adverse health effects. Swimming in rivers, streams and lakes with high levels of fecal contamination are regularly linked to outbreaks of gastrointestinal illness and related infections. Wh...

  18. The effects of swimming pattern on the energy use of gilthead seabream (Sparus aurata L.)

    DEFF Research Database (Denmark)

    Steinhausen, Maria Faldborg; Steffensen, John Fleng; Andersen, Niels Gerner

    2010-01-01

    Oxygen consumption ( ) was measured for gilthead seabream (Sparus aurata) during spontaneous and forced activities. During spontaneous activity, the swimming pattern was analysed for the effect on   on the average speed (U), turning rate (¿) and change in speed (¿U). All swimming characteristics...... and   during forced activity was also established. During spontaneous activity, 2.5 times more energy was used than in forced swimming at a speed of 0.5 BL s-1. This indicates that spontaneous swimming costs may be considerably higher compared with those of a fixed swimming speed. However, comparing...... contributed significantly to the source of spontaneous swimming costs, and the models explained up to 58% of the variation in   Prediction of   of fish in field studies can thereby be improved if changes in speed and direction are determined in addition to swimming speed. A relationship between swimming speed...

  19. Indoor swimming pool attendance and respiratory and dermal health in schoolchildren: HITEA Catalonia.

    NARCIS (Netherlands)

    Font-Ribera, L.; Villanueva, C.M.; Gracia-Lavedan, E.; Borràs-Santos, A.; Kogevinas, M.; Zock, J.P.

    2014-01-01

    Background: Health benefits of swimming in pools may outweigh adverse health outcomes in children, but evidence from epidemiological studies is scarce or inconclusive for different health outcomes. We evaluated the association between indoor swimming pool attendance during childhood and respiratory

  20. SWIMS, Sigmund and Winterbon Multiple Scattering of Ion Beams

    International Nuclear Information System (INIS)

    Eyeberger, L.

    1999-01-01

    1 - Description of program or function - SWIMS calculates the angular dispersion of ion beams that undergo small-angle, incoherent multiple scattering by gaseous or solid media. 2 - Method of solution - SWIMS uses the tabulated angular distributions of Sigmund and Winterbon for a Thomas-Fermi screened Coulomb potential. The fraction of the incident beam scattered into a cone defined by the polar angle is computed as a function of that angle for a reduced thickness over the rang of 0.01 to 10

  1. Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

    Centers for Disease Control (CDC) Podcasts

    2008-05-29

    In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.  Created: 5/29/2008 by Emerging Infectious Diseases.   Date Released: 5/29/2008.

  2. Changes over swim lessons in parents' perceptions of children's supervision needs in drowning risk situations: "His swimming has improved so now he can keep himself safe".

    Science.gov (United States)

    Morrongiello, Barbara A; Sandomierski, Megan; Spence, Jeffrey R

    2014-07-01

    The aim of this longitudinal study was to determine how children's participation in swim lessons impacts parents' appraisals of children's drowning risk and need for supervision. Parents with 2-5-year old children enrolled in community swim lessons completed the same survey measures up to 4 times over an 8-month period. Multilevel regression analyses examining temporal relationships between parents' perceptions of their child's swim ability, supervision needs around water, and children's ability to keep themselves safe in drowning risk situations revealed that as children progressed through swim lessons, parents' perceptions of their child's swim ability and their belief that children are capable of keeping themselves safe around water increased. Further, the relation between parents' perceptions of swim ability and judgments of children's supervision needs was mediated through parents' judgment about their child's ability to secure their own safety near water. As parents perceive their child to be accumulating swim skills, they increasingly believe that children are capable of keeping themselves from drowning, and as a result, that less active parent supervision of their child is necessary. Implications of these findings for intervention efforts to counter this unwelcome way of thinking that may arise through continued participation in swim lessons are discussed. Incorporating a parent-focused component into children's learn-to-swim programs to promote more realistic appraisals of children's supervision needs and drowning risks may further enhance the positive benefits that swim lessons have for children's safety.

  3. Swimming black-crowned night-herons (Nycticorax nycticorax) Kleptoparasitize American coots (Fulica americana)

    DEFF Research Database (Denmark)

    Graves, Gary R.

    2015-01-01

    I observed black-crowned night-herons (Nycticorax nycticorax) swimming and kleptoparasitizing American coots (Fulica americana) at an artificial lake in Pinal County, Arizona. This appears to be the first record of interspecific kleptoparasitism by a swimming ardeid.......I observed black-crowned night-herons (Nycticorax nycticorax) swimming and kleptoparasitizing American coots (Fulica americana) at an artificial lake in Pinal County, Arizona. This appears to be the first record of interspecific kleptoparasitism by a swimming ardeid....

  4. Mathematical modelling and simulation of the thermal performance of a solar heated indoor swimming pool

    OpenAIRE

    Mančić Marko V.; Živković Dragoljub S.; Milosavljević Peđa M.; Todorović Milena N.

    2014-01-01

    Buildings with indoor swimming pools have a large energy footprint. The source of major energy loss is the swimming pool hall where air humidity is increased by evaporation from the pool water surface. This increases energy consumption for heating and ventilation of the pool hall, fresh water supply loss and heat demand for pool water heating. In this paper, a mathematical model of the swimming pool was made to assess energy demands of an indoor swimming po...

  5. 76 FR 42048 - Safety Zones; Swimming Events in Captain of the Port Boston Zone

    Science.gov (United States)

    2011-07-18

    ...-AA00 Safety Zones; Swimming Events in Captain of the Port Boston Zone AGENCY: Coast Guard, DHS. ACTION... events within the Captain of the Port (COTP) Boston Zone for swimming events. This action is necessary to... property on navigable waters from the hazardous nature of swimming events such as large numbers of swimmers...

  6. Schooling reduces energy consumption in swimming male European eels, Anguilla anguilla L.

    NARCIS (Netherlands)

    Burgerhout, E.; Tudorache, C.; Brittijn, S.A.; Palstra, A.P.; Dirks, R.P.; Thillart, G.E.E.J.M.

    2013-01-01

    During migration, swimming in schools provides fish with a number of behavioural and ecological advantages, including increased food supply and reduced predation risk. Previous work shows that carangiform and tunniform swimming result in energetic advantages for individuals using a diamond swimming

  7. Swimming Lessons: Learning, New Materialisms, Posthumanism, and Post Qualitative Research Emerge through a Pool Poem

    Science.gov (United States)

    McKnight, Lucinda

    2016-01-01

    This article shifts from the formal learning spaces of school and university to an Australian public swimming pool to playfully engage some of the dilemmas that recent theory poses for curriculum studies. The article enacts multiple diffractions (Barad, 2007) as theory becomes swimming and swimming becomes theory, and ideas and movements are…

  8. 77 FR 41271 - Safety Zone; Newburgh to Beacon Swim, Newburgh, Hudson River, NY

    Science.gov (United States)

    2012-07-13

    ... 1625-AA00 Safety Zone; Newburgh to Beacon Swim, Newburgh, Hudson River, NY AGENCY: Coast Guard, DHS... navigable waters of the Hudson River, NY in the vicinity of Newburgh, NY for the annual Newburgh Beacon Swim... Beacon Swim is an annual recurring event that has a permanent safety zone found at 33 CFR 165.160. The...

  9. The Effect of Rehearsal Learning and Warm-up on the Speed of Different Swimming Strokes

    Science.gov (United States)

    Magno, Carlo; Mascardo, Elizabeth

    2009-01-01

    The study investigated the effects of rehearsal learning and warm-up exercise on the time of performing different swimming strokes. The study was conducted among 202 college freshmen students taking up a course on physical education concentrated in swimming. The design employed is a mixed factorial (2 X 2) where time of swimming is measured before…

  10. THE EFFECTS OF DIFFERENT MODELS OF SWIMMING TRAINING (DEFINED IN RELATION TO ANAEROBIC THRESHOLD ON THE INCREASE OF SWIM SPEED

    Directory of Open Access Journals (Sweden)

    Dragan Krivokapić

    2007-05-01

    Full Text Available On the sample of 32 fourth grade students of some Belgrade highs schools, who had the physical education classes carried out at the city’s swimming pools, an attempt was made to evaluate the effects of the two different programmes of swimming training in different intensity zones, defi ned relative to the anaerobic threshold. The examinees were divided into two groups out of 15 i.e. 17 participants who were not (according to statistics signifi cantly different in terms of average time and heart frequency during the 400 m swimming test and heart frequency and time measured after 50 m in the moment of reaching the anaerobic threshold. The fi rst training model consisted of swimming at the intensity level within the zone below anaerobic threshold, while the second model involved occasional swimming at a higher intensity sometimes surpassing the anaerobic threshold. The experimentalprogramme with both sub-groups lasted 8 weeks with 3 training sessions per week, 2 ‘of which we’re identical for both experimental groups, with the third one differing regarding the swimming intensity, this in the fi rst group being still in the zone below, and in the second group occasionally in the zone above the anaerobic threshold. The amount of training and the duration were the same in both programmes. The aim of the research , was to evaluate and to compare the effects of the two training models, using as the basic criteria possible changes of average time and heart frequency during the 400 m swimming test and heart frequency and time measured after 50 m in the moment of reaching the anaerobic thereshold. On the basis of the statistical analysis of the obtained data, it is possible to conclude that in both experimental groups there were statistically signifi cant changes of average values concerning all the physiological variables. Although the difference in effi ciency of applied experimental programmes is not defi ned, we can claim that both of experimental

  11. Critical force during tethered swimming for the evaluation of aerobic capacity and prediction of performances in freestyle swimming

    OpenAIRE

    Marcelo Papoti; Ricardo Vitório; Gustavo Gomes Araújo; Luiz Eduardo Barreto Martins; Sérgio Augusto Cunha; Claudio Alexandre Gobatto

    2010-01-01

    The present study investigated the relationship of critical force (Fcrit) with lactate threshold (LLNA) and the intensity corresponding to VO2max (iVO2max) in tethered swimming (TS), and their correlation with maximal performance in 400-m (V400) and 30-min (VT30) freestyle swimming (FS). Seven swimmers were submitted to a TS incremental test for the determination of LLNA and iVO2max. For the determination of Fcrit, the swimmers performed four exercises to exhaustion at intensities (F) corresp...

  12. 33 CFR 207.610 - St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and navigation of the harbor...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and navigation of the harbor and U.S. breakwater. 207.610 Section 207... NAVIGATION REGULATIONS § 207.610 St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and...

  13. Swimming pools and intra-city climates: Influences on residential ...

    African Journals Online (AJOL)

    While determinants such as household income, regional climate, water price, property size and household occupancy have been comprehensively studied and modelled, other determinants such as swimming pools and intra-city climates have not. This study examines residential water consumption in the City of Cape Town ...

  14. Swimming behaviour of Daphnia clones: differentiation through predator infochemicals

    NARCIS (Netherlands)

    Weber, A.; Van Noordwijk, A.J.

    2002-01-01

    We studied variation in small-scale swimming behavior (SSB) in four clones of Daphnia galeata (water flea) in response to predator infochemicals. The aim of this study was 3-fold. First, we tested for differences in SSB in Daphnia; second, we examined the potential of differences in SSB to explain

  15. Using adolescent interest in swimming to accomplish utilitarian ...

    African Journals Online (AJOL)

    As drowning is a serious threat to life, aquatic education is a necessity. The aim of this study was to carry out a quantitative analysis of students' expressions of interest to participate in swimming activities compared to interests in other forms of physical activity. A total of 1328 girls and boys aged 16–18 years participated in ...

  16. Hydrodynamics of burst swimming fish larvae; a conceptual model approach

    NARCIS (Netherlands)

    Verhagen, J.H.G.

    2004-01-01

    Burst swimming of fish larvae is analysed from a hydrodynamic point of view. A picture of the expected flow pattern is presented based on information in literature on unsteady-flow patterns around obstacles in the intermediate Reynolds number region. It is shown that the acceleration stage of burst

  17. Automated visual tracking for studying the ontogeny of zebrafish swimming

    NARCIS (Netherlands)

    Fontaine, E.; Lentink, D.; Kranenbarg, S.; Müller, U.K.; Leeuwen, van J.L.; Barr, A.H.; Burdick, J.W.

    2008-01-01

    The zebrafish Danio rerio is a widely used model organism in studies of genetics, developmental biology, and recently, biomechanics. In order to quantify changes in swimming during all stages of development, we have developed a visual tracking system that estimates the posture of fish. Our current

  18. Estimated environmental radionuclide transfer and deposition into outdoor swimming pools

    International Nuclear Information System (INIS)

    Tagami, Kazumi; Nagata, Izumi; Sueki, Keisuke

    2014-01-01

    In 2011, a large radioactive discharge occurred at the Fukushima Daiichi nuclear power plant. This plant is located within a climatically temperate region where outdoor swimming pools are popular. Although it is relatively easy to decontaminate pools by refilling them with fresh water, it is difficult to maintain safe conditions given highly contaminated diurnal dust falls from the surrounding contaminated ground. Our objectives in this paper were to conduct daily radioactivity measurements, to determine the quantity of radioactive contaminants from the surrounding environment that invade outdoor pools, and to investigate the efficacy of traditional pool cleaners in removing radioactive contaminants. The depositions in the paper filterable particulates ranged from 0 to 62,5 Bq/m 2 /day, with the highest levels found in the southern Tohoku District containing Fukushima Prefecture and in the Kanto District containing Tokyo Metro. They were approximately correlated with the ground contamination. Traditional pool cleaners eliminated 99% of contaminants at the bottom of the pool, reducing the concentration to 41 Bq/m 2 after cleaning. Authors recommended the deposition or the blown radionuclides into outdoor swimming pools must be considered into pool regulations when the environments exactly polluted with radionuclides. - Highlights: • Deposition into outdoor swimming pool in a habitable areas estimated 72 Bq/m 2 /day. • More than 500 Bq/m 2 /day deposition will exceed our national guideline (10 Bq/l) of swimming pool. • Vacuum pool cleaner eliminates 99% radionuclides deposition

  19. Early Years Swimming: A Way of Supporting School Transitions?

    Science.gov (United States)

    Jorgensen, Robyn

    2016-01-01

    Informal learning contexts may provide opportunities for adding capital to young children in their years prior to schooling. This paper explores the potential of the early-years swim context to add capital to young children that may position them favourably for the transition to school. Using Bourdieu's notion of capital, the paper discusses the…

  20. The economics of age-group swimming in Ontario.

    Science.gov (United States)

    Eynon, R B; Kitchen, P D; Semotiuk, D M

    1980-09-01

    This study investigated the socio-economic status of the parents of Ontario swimmers and parental expenditures, in terms of time and money, in support of competitive swimming. Questionnaires were mailed to a sample of 400 families of Ontario competitive swimmers. Spearman rho analyses were used to determine the relationships of membership fee, total cost and total time spent by the parents to the ability and age of the swimmer and the number of hours of practice and swim meets. Parents of Ontario competitive swimmers are upper middle class and devote a great deal of their time (X = 433 hours) and money (X = $744.00) annually to competitive swimming. Total expenditures and time spend by the parents were greater for those children were young and also for those whose children demonstrated greater ability (i.e., closer to Ontario record). Spearman rho analyses suggested that membership fees are not determined on the basis of age, number of practice hours or number of swim meets.

  1. EFFECTS OF DISTANCE SPECIALIZATION ON THE BACKSTROKE SWIMMING KINEMATICS

    Directory of Open Access Journals (Sweden)

    Cortesi Matteo

    2012-09-01

    Full Text Available The purpose of the present study was to investigate different biomechanical variables of backstroke technique in swimmers specialized in different distance events, in order to investigate the capacity to modify the timing of the arm stroke when changing the swimming velocity from sub-maximal to maximal. Two 25-m backstroke trials respectively at 70% of maximum velocity (V70 and at 100% of maximum velocity (Vmax were performed by 9 200-m distance swimmers and 9 50-m distance swimmers. Swimming velocity, stroke length, stroke rate, duration of different phases of the arm stroke and selected kinematic variables were assessed in both cases. In the 50-m distance swimmers, the duration of the propulsive phase at Vmax, expressed as a percentage of the duration of the total underwater arm stroke, increased significantly (p = 0.001 with increasing swimming velocity. Specifically, both the pull and push phases were fundamental in the increase of duration of the propulsive phase. When compared to 200-m specialists, 50-m distance swimmers seem to be more able to modify their arm stroke phases duration when increasing the swimming velocity in backstroke

  2. Swimming Safely (A Minute of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2014-05-22

    Almost 4,000 people die from drowning each year in the U.S. You can also get sick at the pool. This podcast discusses swimming pool safety tips.  Created: 5/22/2014 by MMWR.   Date Released: 5/22/2014.

  3. Safe Swimming (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2017-06-01

    Swimmers can take simple steps to help protect themselves and others from germs that can spread in the water and cause illness. In this podcast Michele Hlavsa discusses ways to stay healthy while swimming.  Created: 6/1/2017 by MMWR.   Date Released: 6/1/2017.

  4. Safe Swimming (A Minute of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2017-06-01

    Most outbreaks linked to pools and water playgrounds are caused by Cryptosporidium. This podcast discusses ways to keep you healthy and safe while swimming.  Created: 6/1/2017 by MMWR.   Date Released: 6/1/2017.

  5. Efficient collective swimming by harnessing vortices through deep reinforcement learning.

    Science.gov (United States)

    Verma, Siddhartha; Novati, Guido; Koumoutsakos, Petros

    2018-06-05

    Fish in schooling formations navigate complex flow fields replete with mechanical energy in the vortex wakes of their companions. Their schooling behavior has been associated with evolutionary advantages including energy savings, yet the underlying physical mechanisms remain unknown. We show that fish can improve their sustained propulsive efficiency by placing themselves in appropriate locations in the wake of other swimmers and intercepting judiciously their shed vortices. This swimming strategy leads to collective energy savings and is revealed through a combination of high-fidelity flow simulations with a deep reinforcement learning (RL) algorithm. The RL algorithm relies on a policy defined by deep, recurrent neural nets, with long-short-term memory cells, that are essential for capturing the unsteadiness of the two-way interactions between the fish and the vortical flow field. Surprisingly, we find that swimming in-line with a leader is not associated with energetic benefits for the follower. Instead, "smart swimmer(s)" place themselves at off-center positions, with respect to the axis of the leader(s) and deform their body to synchronize with the momentum of the oncoming vortices, thus enhancing their swimming efficiency at no cost to the leader(s). The results confirm that fish may harvest energy deposited in vortices and support the conjecture that swimming in formation is energetically advantageous. Moreover, this study demonstrates that deep RL can produce navigation algorithms for complex unsteady and vortical flow fields, with promising implications for energy savings in autonomous robotic swarms.

  6. Core neutronics of a swimming pool research reactor

    International Nuclear Information System (INIS)

    Mannan, M.A.; Mondal, M.A.W.; Pervini, M.E.

    1981-01-01

    The initial cores of the 5 MW swimming pool research reactor of the Nuclear Research Centre, Tehran have been analyzed using the computer codes METHUSELAH and EQUIPOISE. The effective multiplication factor, critical mass, moderator temperature and void coefficients of the core have been calculated and compared with vendor's values. Calculated values agree reasonably well with the vendor's results. (author)

  7. Workflow Lexicons in Healthcare: Validation of the SWIM Lexicon.

    Science.gov (United States)

    Meenan, Chris; Erickson, Bradley; Knight, Nancy; Fossett, Jewel; Olsen, Elizabeth; Mohod, Prerna; Chen, Joseph; Langer, Steve G

    2017-06-01

    For clinical departments seeking to successfully navigate the challenges of modern health reform, obtaining access to operational and clinical data to establish and sustain goals for improving quality is essential. More broadly, health delivery organizations are also seeking to understand performance across multiple facilities and often across multiple electronic medical record (EMR) systems. Interpreting operational data across multiple vendor systems can be challenging, as various manufacturers may describe different departmental workflow steps in different ways and sometimes even within a single vendor's installed customer base. In 2012, The Society for Imaging Informatics in Medicine (SIIM) recognized the need for better quality and performance data standards and formed SIIM's Workflow Initiative for Medicine (SWIM), an initiative designed to consistently describe workflow steps in radiology departments as well as defining operational quality metrics. The SWIM lexicon was published as a working model to describe operational workflow steps and quality measures. We measured the prevalence of the SWIM lexicon workflow steps in both academic and community radiology environments using real-world patient observations and correlated that information with automatically captured workflow steps from our clinical information systems. Our goal was to measure frequency of occurrence of workflow steps identified by the SWIM lexicon in a real-world clinical setting, as well as to correlate how accurately departmental information systems captured patient flow through our health facility.

  8. Unsteady computational fluid dynamics in front crawl swimming.

    Science.gov (United States)

    Samson, Mathias; Bernard, Anthony; Monnet, Tony; Lacouture, Patrick; David, Laurent

    2017-05-01

    The development of codes and power calculations currently allows the simulation of increasingly complex flows, especially in the turbulent regime. Swimming research should benefit from these technological advances to try to better understand the dynamic mechanisms involved in swimming. An unsteady Computational Fluid Dynamics (CFD) study is conducted in crawl, in order to analyse the propulsive forces generated by the hand and forearm. The k-ω SST turbulence model and an overset grid method have been used. The main objectives are to analyse the evolution of the hand-forearm propulsive forces and to explain this relative to the arm kinematics parameters. In order to validate our simulation model, the calculated forces and pressures were compared with several other experimental and numerical studies. A good agreement is found between our results and those of other studies. The hand is the segment that generates the most propulsive forces during the aquatic stroke. As the pressure component is the main source of force, the orientation of the hand-forearm in the absolute coordinate system is an important kinematic parameter in the swimming performance. The propulsive forces are biggest when the angles of attack are high. CFD appears as a very valuable tool to better analyze the mechanisms of swimming performance and offers some promising developments, especially for optimizing the performance from a parametric study.

  9. Pelagic behaviour of reservoir fishes: sinusoidal swimming and associated behaviour

    OpenAIRE

    JAROLÍM, Oldřich

    2009-01-01

    Annotation Long-term fixed-location hydroacoustic study with uplooking transducer was performed during 2005 in Římov reservoir, Czech Republic. It dealt mainly with fish behaviour in the open water of reservoir, especially with sinusoidal swimming behaviour. The dependence of pelagic fish behaviour on environmental conditions was also studied.

  10. Getting in Shape : Swimming with Stokes and Surfing with Brinkman

    NARCIS (Netherlands)

    Bet, B.P.

    2018-01-01

    In this dissertation, we investigate the effect of shape on the motion of microscopic particles that perform a swimming motion or ‘surf’, driven by an external flow, through microscopic channels. These motions take place in a fluid, and fluid motion is in general described by the Navier-Stokes

  11. Effect of Beetroot Juice Supplementation on Aerobic Response during Swimming

    Directory of Open Access Journals (Sweden)

    Marco Pinna

    2014-01-01

    Full Text Available The beneficial effects of beetroot juice supplementation (BJS have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO2, carbon dioxide production (VCO2, pulmonary ventilation (VE, and aerobic energy cost (AEC of swimming were measured. One was a control swimming test (CSW and the other a swimming test after six days of BJS (0.5l/day organic beetroot juice containing about 5.5 mmol of NO3−. Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively. Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg−1·h−1 during the BJS test. The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.

  12. Effect of beetroot juice supplementation on aerobic response during swimming.

    Science.gov (United States)

    Pinna, Marco; Roberto, Silvana; Milia, Raffaele; Marongiu, Elisabetta; Olla, Sergio; Loi, Andrea; Migliaccio, Gian Mario; Padulo, Johnny; Orlandi, Carmine; Tocco, Filippo; Concu, Alberto; Crisafulli, Antonio

    2014-01-29

    The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO₂), carbon dioxide production (VCO₂), pulmonary ventilation (VE), and aerobic energy cost (AEC) of swimming were measured. One was a control swimming test (CSW) and the other a swimming test after six days of BJS (0.5 l/day organic beetroot juice containing about 5.5 mmol of NO₃⁻). Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively). Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg⁻¹1·h⁻¹ during the BJS test). The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.

  13. Life cycle environmental implications of residential swimming pools.

    Science.gov (United States)

    Forrest, Nigel; Williams, Eric

    2010-07-15

    Ownership of private swimming pools in the U.S. grew 2 to 4% per annum from 1997 to 2007. The environmental implications of pool ownership are analyzed by hybrid life cycle assessment (LCA) for nine U.S. cities. An operational model is constructed estimating consumption of chemicals, water, and energy for a typical residential pool. The model incorporates geographical climatic variations and upstream water and energy use from electricity and water supply networks. Results vary considerably by city: a factor of 5-6 for both water and energy use. Water use is driven by aridness and length of the swimming season, while energy use is mainly driven by length of the swimming season. Water and energy impacts of pools are significant, particularly in arid climates. In Phoenix for example pools account for 22% and 13% of a household's electricity and water use, respectively. Measures to reduce water and energy use in pools such as optimizing the pump schedule and covering the pool in winter can realize greater savings than many common household efficiency improvements. Private versus community pools are also compared. Community pools in Phoenix use 60% less swimming pool water and energy per household than subdivisions without community pools.

  14. Numerical and experimental investigations of human swimming motions.

    Science.gov (United States)

    Takagi, Hideki; Nakashima, Motomu; Sato, Yohei; Matsuuchi, Kazuo; Sanders, Ross H

    2016-08-01

    This paper reviews unsteady flow conditions in human swimming and identifies the limitations and future potential of the current methods of analysing unsteady flow. The capability of computational fluid dynamics (CFD) has been extended from approaches assuming steady-state conditions to consideration of unsteady/transient conditions associated with the body motion of a swimmer. However, to predict hydrodynamic forces and the swimmer's potential speeds accurately, more robust and efficient numerical methods are necessary, coupled with validation procedures, requiring detailed experimental data reflecting local flow. Experimental data obtained by particle image velocimetry (PIV) in this area are limited, because at present observations are restricted to a two-dimensional 1.0 m(2) area, though this could be improved if the output range of the associated laser sheet increased. Simulations of human swimming are expected to improve competitive swimming, and our review has identified two important advances relating to understanding the flow conditions affecting performance in front crawl swimming: one is a mechanism for generating unsteady fluid forces, and the other is a theory relating to increased speed and efficiency.

  15. THE USE OF NEURAL NETWORK TECHNOLOGY TO MODEL SWIMMING PERFORMANCE

    Directory of Open Access Journals (Sweden)

    António José Silva

    2007-03-01

    Full Text Available The aims of the present study were: to identify the factors which are able to explain the performance in the 200 meters individual medley and 400 meters front crawl events in young swimmers, to model the performance in those events using non-linear mathematic methods through artificial neural networks (multi-layer perceptrons and to assess the neural network models precision to predict the performance. A sample of 138 young swimmers (65 males and 73 females of national level was submitted to a test battery comprising four different domains: kinanthropometric evaluation, dry land functional evaluation (strength and flexibility, swimming functional evaluation (hydrodynamics, hydrostatic and bioenergetics characteristics and swimming technique evaluation. To establish a profile of the young swimmer non-linear combinations between preponderant variables for each gender and swim performance in the 200 meters medley and 400 meters font crawl events were developed. For this purpose a feed forward neural network was used (Multilayer Perceptron with three neurons in a single hidden layer. The prognosis precision of the model (error lower than 0.8% between true and estimated performances is supported by recent evidence. Therefore, we consider that the neural network tool can be a good approach in the resolution of complex problems such as performance modeling and the talent identification in swimming and, possibly, in a wide variety of sports

  16. Simulations of the burst and coast swimming behavior of fish

    Science.gov (United States)

    Zhou, Quan; Moored, Keith; Smits, Alexander

    2013-11-01

    An investigation into the burst and coast swimming behavior of fish is simulated with a 2-D, inviscid Boundary Element Method. The fish is modeled as a thin pitching panel that is allowed to free swim. A simple drag model is used where drag is proportional to the velocity squared in order to calculate the cruising velocity. The burst-coast behavior is modeled by a coasting phase, where the panel is motionless, and a burst phase, where the panel pitches with a single sine wave motion. Varying the frequency of the fin-beat and the duration of the duty cycle (the ratio of the burst-phase to the entire period), it is found that it is possible to alter swimming motion to yield a decrease of 50% in the cost of transport with no sacrifice of time-averaged cruising velocity. The analyses of the wake structure demonstrate how vortices shed by the fish affect and shape swimming dynamics. Supported by the Office of Naval Research under Program Director Dr. Bob Brizzolara, MURI grant number N00014-08-1-0642.

  17. Littoral cells and harbor dredging along the California coast

    Science.gov (United States)

    Griggs, Gary B.

    1987-02-01

    Beach compartments or littoral cells form the framework for our understanding of the sources, transport, and sinks of sand in the nearshore zone. In general, along the California coast, beach sand is derived from rivers or clifferosion, moves alongshore under the influence of the prevailing waver conditions, and ultimately is lost either to a submarine canyon or a dune field. Marinas or harbors built either between or at the upcoast ends of beach compartments have been relatively maintenance-free, because of a lack of significant littoral drift at these locations. On the other hand, those harbors built in the middle reaches or at the downcoast ends of littoral cells have had expensive annual dredging problems, because of the interruption of large volumes of littoral drift. Although engineers have labored for years on various breakwater, jetty, or entrance channel configurations, the actual design utilized is of secondary importance. The critical factors are harbor location within a littoral cell and annual litoral drift volume.

  18. Respiratory properties of blood in the harbor porpoise, Phocoena phocoena

    DEFF Research Database (Denmark)

    Soegaard, Lisette B; Hansen, Marie N; van Elk, Cornelis

    2012-01-01

    Harbor porpoises are active divers that exchange O(2) and CO(2) with the environment during a fast single breath upon surfacing. We investigated blood O(2)-transporting properties, buffer characteristics, Cl(-) transport via the erythrocyte anion exchanger (AE1), circulating nitric oxide metaboli......Harbor porpoises are active divers that exchange O(2) and CO(2) with the environment during a fast single breath upon surfacing. We investigated blood O(2)-transporting properties, buffer characteristics, Cl(-) transport via the erythrocyte anion exchanger (AE1), circulating nitric oxide....... The true plasma non-bicarbonate buffer value was moderately higher than in terrestrial mammals and increased upon deoxygenation. Plasma bicarbonate was also relatively high, contributing to increase the overall buffer capacity. The apparent Cl(-) permeability of harbor porpoise erythrocytes was similar......, plasma nitrate and hemoglobin-mediated nitrite reduction were elevated compared with mammalian standards, suggesting that increased nitric oxide bioavailability and nitrite-derived nitric oxide could play important roles in diving physiology....

  19. 33 CFR 110.87 - Henderson Harbor, N.Y.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Henderson Harbor, N.Y. 110.87... ANCHORAGE REGULATIONS Special Anchorage Areas § 110.87 Henderson Harbor, N.Y. (a) Area A. The area in the... latitude 43°51′08.8″ N, longitude 76°12′08.9″ W, thence to latitude 43°51′09.0″ N, longitude 76°12′19.0″ W...

  20. Extrachromosomal deoxyribonucleic acid in R factor-harboring Enterobacteriaceae

    DEFF Research Database (Denmark)

    Møller, JK; Bak, AL; Christiansen, C

    1976-01-01

    Extrachromosomal deoxyribonucleic acid (DNA) from 24 different R factor-harboring Enterobacteriaceae was isolated and characterized by analytical ultracentrifugation and electron microscopy. The R factors represented 15 different patterns of transferable drug resistance found in enterobacteria from...... from 1.700 to 1.720 g/cm3. The majority of the bacteria contained extrachromosomal DNAs of various densities. Three-fourths of the R factors were classified as fi+. The investigation illustrates the extensive variability in the physical characteristics of plasmid DNA from R factor-harboring strains....

  1. SWIMMING ENHANCES BONE MASS ACQUISITION IN GROWING FEMALE RATS

    Directory of Open Access Journals (Sweden)

    Joanne McVeigh

    2010-12-01

    Full Text Available Growing bones are most responsive to mechanical loading. We investigated bone mass acquisition patterns following a swimming or running exercise intervention of equal duration, in growing rats. We compared changes in bone mineral properties in female Sprague Dawley rats that were divided into three groups: sedentary controls (n = 10, runners (n = 8 and swimmers (n = 11. Runners and swimmers underwent a six week intervention, exercising five days per week, 30min per day. Running rats ran on an inclined treadmill at 0.33 m.s-1, while swimming rats swam in 25oC water. Dual energy X-ray absorptiometry scans measuring bone mineral content (BMC, bone mineral density (BMD and bone area at the femur, lumbar spine and whole body were recorded for all rats before and after the six week intervention. Bone and serum calcium and plasma parathyroid hormone (PTH concentrations were measured at the end of the 6 weeks. Swimming rats had greater BMC and bone area changes at the femur and lumbar spine (p < 0.05 than the running rats and a greater whole body BMC and bone area to that of control rats (p < 0.05. There were no differences in bone gain between running and sedentary control rats. There was no significant difference in serum or bone calcium or PTH concentrations between the groups of rats. A swimming intervention is able to produce greater beneficial effects on the rat skeleton than no exercise at all, suggesting that the strains associated with swimming may engender a unique mechanical load on the bone

  2. Swimming Training Reduces Neuroma Pain by Regulating Neurotrophins.

    Science.gov (United States)

    Tian, Jinge; Yu, Tingting; Xu, Yongming; Pu, Shaofeng; Lv, Yingying; Zhang, Xin; DU, Dongping

    2018-01-01

    Neuroma formation after peripheral nerve transection leads to severe neuropathic pain in amputees. Previous studies suggested that physical exercise could bring beneficial effect on alleviating neuropathic pain. However, the effect of exercise on neuroma pain still remained unclear. In addition, long-term exercise can affect the expression of neurotrophins (NT), such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), which play key roles in nociceptor sensitization and nerve sprouting after nerve injury. Here, we investigated whether long-term swimming exercise could relieve neuroma pain by modulating NT expression. We used a tibial neuroma transposition (TNT) rat model to mimic neuroma pain. After TNT surgery, rats performed swimming exercise for 5 wk. Neuroma pain and tactile sensitivities were detected using von Frey filaments. Immunofluorescence was applied to analyze neuroma formation. NGF and BDNF expressions in peripheral neuroma, dorsal root ganglion, and the spinal cord were measured using enzyme-linked immunosorbent assay and Western blotting. TNT led to neuroma formation, induced neuroma pain, and mechanical allodynia in hind paw. Five-week swimming exercise inhibited neuroma formation and relieved mechanical allodynia in the hind paw and neuroma pain in the lateral ankle. The analgesic effect lasted for at least 1 wk, even when the exercise ceased. TNT elevated the expressions of BDNF and NGF in peripheral neuroma, dorsal root ganglion, and the spinal cord to different extents. Swimming also decreased the elevation of NT expression. Swimming exercise not only inhibits neuroma formation induced by nerve transection but also relieves pain behavior. These effects might be associated with the modulation of NT.

  3. Physical forces shape group identity of swimming Pseudomonas putida cells

    Directory of Open Access Journals (Sweden)

    David Rodriguez-Espeso

    2016-09-01

    Full Text Available The often striking macroscopic patterns developed by motile bacterial populations on agar plates are a consequence of the environmental conditions where the cells grow and spread. Parameters such as medium stiffness and nutrient concentration have been reported to alter cell swimming behavior, while mutual interactions among populations shape collective patterns. One commonly observed occurrence is the mutual inhibition of clonal bacteria when moving towards each other, which results in a distinct halt at a finite distance on the agar matrix before having direct contact. The dynamics behind this phenomenon (i.e. intolerance to mix in time and space with otherwise identical others has been traditionally explained in terms of cell-to-cell competition/cooperation regarding nutrient availability. In this work, the same scenario has been revisited from an alternative perspective: the effect of the physical mechanics that frame the process, in particular the consequences of collisions between moving bacteria and the semi-solid matrix of the swimming medium. To this end we set up a simple experimental system in which the swimming patterns of Pseudomonas putida were tested with different geometries and agar concentrations. A computational analysis framework that highlights cell-to-medium interactions was developed to fit experimental observations. Simulated outputs suggested that the medium is compressed in the direction of the bacterial front motion. This phenomenon generates what was termed a compression wave that goes through the medium preceding the swimming population and that determines the visible high-level pattern. Taken together, the data suggested that the mechanical effects of the bacteria moving through the medium created a factual barrier that impedes to merge with neighboring cells swimming from a different site. The resulting divide between otherwise clonal bacteria is thus brought about by physical forces –not genetic or metabolic

  4. The performance effect of centralizing a nation's elite swim program.

    Science.gov (United States)

    Allen, Sian V; Vandenbogaerde, Tom J; Hopkins, Will G

    2015-03-01

    Many national sporting organizations recruit talented athletes to well-resourced centralized training squads to improve their performance. To develop a method to monitor performance progression of swimming squads and to use this method to assess the progression of New Zealand's centralized elite swimming squad. Best annual long-course competition times of all New Zealand swimmers with at least 3 y of performances in an event between 2002 and 2013 were downloaded from takeyourmarks.com (~281,000 times from ~8500 swimmers). A mixed linear model accounting for event, age, club, year, and elite-squad membership produced estimates of mean annual performance for 175 swim clubs and mean estimates of the deviation of swimmers' performances from their individual quadratic trajectories after they joined the elite squad. Effects were evaluated using magnitude-based inferences, with a smallest important improvement in swim time of -0.24%. Before 2009, effects of elite-squad membership were mostly unclear and trivial to small in magnitude. Thereafter, both sexes showed clear additional performance enhancements, increasing from large in 2009 (males -1.4%±0.8%, females -1.5%±0.8%; mean±90% confidence limits) to extremely large in 2013 (males -6.8%±1.7%, females -9.8%±2.9%). Some clubs also showed clear performance trends during the 11-y period. Our method of quantifying deviations from individual trends in competition performance with a mixed model showed that Swimming New Zealand's centralization strategy took several years to produce substantial performance effects. The method may also be useful for evaluating performance-enhancement strategies introduced at national or club level in other sports.

  5. THE RELATIONS BETWEEN ANTHROPOLOGICAL DIMENSIONS AND SWIMMING THE BREAST STROKE

    Directory of Open Access Journals (Sweden)

    Milomir Trivun

    2011-09-01

    Full Text Available at the Faculty of the Physical Education and Sport in East Sarajevo during 2009/10. Students were 22 years ± 6 months old. There was done the comparison in the following parameters: 11 variables of the anthropological status and one variable of the swimming the breast stroke at 50m. Predictable variables of the anthropological dimensions were: height, weight, shoulders’ breadth, hips’ breadth, skins’ folds of the back, skins’ folds of the upper arm, skins’ folds of the abdomen, the measurement of the upper arm, the measurement of the thigh, the measurement of the shank and the diameter of the knee’s joint. The criterion’s variable referred to the results’ success in swimming the breast stroke at 50m. The descriptive statistics was used in the research. The measures of central tendencies mean, minimum, maximum, standard deviation are expressed by descriptive statistics. For the correlation of the results of the anthropological status with the results at swimming the breast stroke at 50m the regressive analysis was used. The results of the group of 23 tested male students in 2009/10, which were shown in the measures of central tendencies, descriptive statistics and regressive analysis of the set of 11 predictable variables of anthropological students’ dimensions were compared with the results of the criterion’s variable shown by swimming the butterfly. During the regressive analysis, the list of the data which contains the information about the regression parameters and statistic values relevant for described testing procedures of the marked parameters were got. In this case the parameters were 11 variables of anthropological dimensions and the variables of the results‘ success in swimming the breast stroke at 50m.

  6. Swimming-induced pulmonary oedema an uncommon condition diagnosed with POCUS ultrasound.

    Science.gov (United States)

    Alonso, Joaquín Valle; Chowdhury, Motiur; Borakati, Raju; Gankande, Upali

    2017-12-01

    Swimming Induced Pulmonary Edema, or SIPE, is an emerging condition occurring in otherwise healthy individuals during surface swimming or diving that is characterized by cough, dyspnea, hemoptysis, and hypoxemia. It is typically found in those who spend time in cold water exercise with heavy swimming and surface swimming, such as civilian training for iron Man, triathalon, and military training. We report the case of a highly trained young female swimmer in excellent cardiopulmonary health, who developed acute alveolar pulmonary oedema in an open water swimming training diagnosed in the emergency department using POCUS ultrasound. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Intra- and Intersexual swim bladder dimorphisms in the plainfin midshipman fish (Porichthys notatus): Implications of swim bladder proximity to the inner ear for sound pressure detection.

    Science.gov (United States)

    Mohr, Robert A; Whitchurch, Elizabeth A; Anderson, Ryan D; Forlano, Paul M; Fay, Richard R; Ketten, Darlene R; Cox, Timothy C; Sisneros, Joseph A

    2017-11-01

    The plainfin midshipman fish, Porichthys notatus, is a nocturnal marine teleost that uses social acoustic signals for communication during the breeding season. Nesting type I males produce multiharmonic advertisement calls by contracting their swim bladder sonic muscles to attract females for courtship and spawning while subsequently attracting cuckholding type II males. Here, we report intra- and intersexual dimorphisms of the swim bladder in a vocal teleost fish and detail the swim bladder dimorphisms in the three sexual phenotypes (females, type I and II males) of plainfin midshipman fish. Micro-computerized tomography revealed that females and type II males have prominent, horn-like rostral swim bladder extensions that project toward the inner ear end organs (saccule, lagena, and utricle). The rostral swim bladder extensions were longer, and the distance between these swim bladder extensions and each inner-ear end organ type was significantly shorter in both females and type II males compared to that in type I males. Our results revealed that the normalized swim bladder length of females and type II males was longer than that in type I males while there was no difference in normalized swim bladder width among the three sexual phenotypes. We predict that these intrasexual and intersexual differences in swim bladder morphology among midshipman sexual phenotypes will afford greater sound pressure sensitivity and higher frequency detection in females and type II males and facilitate the detection and localization of conspecifics in shallow water environments, like those in which midshipman breed and nest. © 2017 Wiley Periodicals, Inc.

  8. How the body contributes to the wake in undulatory fish swimming: Flow fields of a swimming eel (Anguilla anguilla)

    NARCIS (Netherlands)

    Müller, Ulrike K.; Smit, Joris; Stamhuis, Eize J.; Videler, John J.

    2001-01-01

    Undulatory swimmers generate thrust by passing a transverse wave down their body. Thrust is generated not just at the tail, but also to a varying degree by the body, depending on the fish's morphology and swimming movements. To examine the mechanisms by which the body in particular contributes to

  9. Predictors of Swimming Ability among Children and Adolescents in the United States

    Directory of Open Access Journals (Sweden)

    Jennifer Pharr

    2018-02-01

    Full Text Available Swimming is an important source of physical activity and a life skill to prevent drowning. However, little research has been conducted to understand predictors of swimming ability. The purpose of this study was to understand factors that predict swimming ability among children and adolescents in the United States (US. This was a cross-sectional survey conducted between February and April of 2017 across five geographically diverse cities. Participants were accessed through the Young Christian Men’s Association (YMCA and included parents of children aged 4–11 years old and adolescents aged 12–17 years old. Independent t-test, analysis of variance (ANOVA, and univariate and multivariate analyses were conducted. Several factors were significant (p ≤ 0.05 predictors of swimming ability and explained 53% of the variance in swimming ability. Variables that were positively associated with swimming ability included: ability of parent(s to swim, child/adolescent age, a best friend who enjoys swimming, water-safety knowledge, pool open all year, and encouragement to swim from parent(s. Variables that were negatively associated with swimming ability included: fear of drowning, being African American, and being female. Interventions and programs to improve the swimming ability of children and adolescents could be developed with these predictors in mind.

  10. Content Validity and Inter-Rater Reliability of the Halliwick-Concept-Based Instrument "Swimming with Independent Measure"

    Science.gov (United States)

    Srsen, Katja Groleger; Vidmar, Gaj; Pikl, Masa; Vrecar, Irena; Burja, Cirila; Krusec, Klavdija

    2012-01-01

    The Halliwick concept is widely used in different settings to promote joyful movement in water and swimming. To assess the swimming skills and progression of an individual swimmer, a valid and reliable measure should be used. The Halliwick-concept-based Swimming with Independent Measure (SWIM) was introduced for this purpose. We aimed to determine…

  11. Swimming training induces liver mitochondrial adaptations to oxidative stress in rats submitted to repeated exhaustive swimming bouts.

    Directory of Open Access Journals (Sweden)

    Frederico D Lima

    Full Text Available BACKGROUND AND AIMS: Although acute exhaustive exercise is known to increase liver reactive oxygen species (ROS production and aerobic training has shown to improve the antioxidant status in the liver, little is known about mitochondria adaptations to aerobic training. The main objective of this study was to investigate the effects of the aerobic training on oxidative stress markers and antioxidant defense in liver mitochondria both after training and in response to three repeated exhaustive swimming bouts. METHODS: Wistar rats were divided into training (n = 14 and control (n = 14 groups. Training group performed a 6-week swimming training protocol. Subsets of training (n = 7 and control (n = 7 rats performed 3 repeated exhaustive swimming bouts with 72 h rest in between. Oxidative stress biomarkers, antioxidant activity, and mitochondria functionality were assessed. RESULTS: Trained group showed increased reduced glutathione (GSH content and reduced/oxidized (GSH/GSSG ratio, higher superoxide dismutase (MnSOD activity, and decreased lipid peroxidation in liver mitochondria. Aerobic training protected against exhaustive swimming ROS production herein characterized by decreased oxidative stress markers, higher antioxidant defenses, and increases in methyl-tetrazolium reduction and membrane potential. Trained group also presented higher time to exhaustion compared to control group. CONCLUSIONS: Swimming training induced positive adaptations in liver mitochondria of rats. Increased antioxidant defense after training coped well with exercise-produced ROS and liver mitochondria were less affected by exhaustive exercise. Therefore, liver mitochondria also adapt to exercise-induced ROS and may play an important role in exercise performance.

  12. Integrated approach to assess ecosystem health in harbor areas.

    Science.gov (United States)

    Bebianno, M J; Pereira, C G; Rey, F; Cravo, A; Duarte, D; D'Errico, G; Regoli, F

    2015-05-01

    Harbors are critical environments with strategic economic importance but with potential environmental impact: health assessment criteria are a key issue. An ecosystem health status approach was carried out in Portimão harbor as a case-study. Priority and specific chemical levels in sediments along with their bioavailability in mussels, bioassays and a wide array of biomarkers were integrated in a biomarker index (IBR index) and the overall data in a weight of evidence (WOE) model. Metals, PAHs, PCBs and HCB were not particularly high compared with sediment guidelines and standards for dredging. Bioavailability was evident for Cd, Cu and Zn. Biomarkers proved more sensitive namely changes of antioxidant responses, metallothioneins and vittellogenin-like proteins. IBR index indicated that site 4 was the most impacted area. Assessment of the health status by WOE approach highlighted the importance of integrating sediment chemistry, bioaccumulation, biomarkers and bioassays and revealed that despite some disturbance in the harbor area, there was also an impact of urban effluents from upstream. Environmental quality assessment in harbors. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. 78 FR 63381 - Safety Zones; Hawaiian Island Commercial Harbors, HI

    Science.gov (United States)

    2013-10-24

    ...; Kaumalapau, Lanai; Kahului, Maui and Kawaihae and Hilo on the Island of Hawaii). The purpose of these safety... the piers faces. (9) All waters of Hilo Harbor, Hawaii immediately adjacent to commercial piers 1 and.... SUMMARY: The Coast Guard is establishing nine (9) permanent safety zones encompassing Hawaii's commercial...

  14. 33 CFR 117.181 - Oakland Inner Harbor Tidal Canal.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Oakland Inner Harbor Tidal Canal. 117.181 Section 117.181 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Tidal Canal. The draws of the Alameda County highway drawbridges at Park Street, mile 5.2; Fruitvale...

  15. 78 FR 21597 - Marine Mammals: Alaska Harbor Seal Habitats

    Science.gov (United States)

    2013-04-11

    ... seek input as to whether management measures are needed, and if so, what types of measures should be... proposed rulemaking (ANPR) on potential management measures to protect glacially-associated harbor seal... need for regulations; (2) the geographic scope and time horizon of regulations; (3) management options...

  16. Quantitative Measures of Anthropogenic Noise on Harbor Porpoises

    DEFF Research Database (Denmark)

    Wisniewska, Danuta Maria; Teilmann, Jonas; Hermannsen, Line

    2016-01-01

    -animal recordings as proxies for actual exposure. Here, we quantify sound exposure levels recorded with a DTAG-3 tag on a captive harbor porpoise exposed to vessel noise in a controlled acoustic environment. Results show that fl ow noise is limiting onboard noise recordings, whereas no evidence of body shading has...

  17. Rhizosphere of rice plants harbor bacteria with multiple plant growth ...

    African Journals Online (AJOL)

    Rhizosphere of rice plants harbor bacteria with multiple plant growth promoting features. ... 45 (39.46%) isolates were capable of producing siderophore, the range of production being 4.50 to 223.26 μg mg-1 protein. Analysis of molecular diversity was made by amplified ribosomal DNA restriction analysis (ARDRA) and ...

  18. U.S. Department of Defense - Pearl Harbor Special

    Science.gov (United States)

    Hawaii saw that seminal moment in history, and those that were there vividly remember that Sunday morning this noise," he said in an oral history on the Pearl Harbor Survivors' Association Web site. " seeing was an attack. "It didn't mean anything to us until a large group of planes came near the

  19. Are parents just treading water? The impact of participation in swim lessons on parents' judgments of children's drowning risk, swimming ability, and supervision needs.

    Science.gov (United States)

    Morrongiello, Barbara A; Sandomierski, Megan; Schwebel, David C; Hagel, Brent

    2013-01-01

    Drowning is a leading cause of child mortality globally. Strategies that have been suggested to reduce pediatric drowning risk include increased parental awareness of children's swimming ability and drowning risk, improved adult supervision of child swimmers, and providing swim lessons to children. This study explored how parents' beliefs relevant to children's drowning risk, perception of children's swimming ability, and judgments of supervision needs changed as children aged two through 5 years accumulated experience in swim lessons, and compared a parent group who received regular, detailed feedback about their child's swim skills with one that did not. Parents completed questionnaire measures near the beginning and end of a series of 10 weekly swim lessons. Results revealed that parental accuracy in judging children's swimming abilities remained relatively poor even though it improved from the beginning to the end of the swim lessons. Supervision needs were underestimated and did not vary with program or change over the course of swim lessons. Children's ability to keep themselves from drowning was overestimated and did not change over lessons or vary with program; parents believed that children could save themselves from drowning by the age of 6.21 years. Parents who had experienced a close call for drowning showed greater awareness of children's drowning risk and endorsed more watchful and proximal supervision. Results suggest that expanding learn-to-swim programs to include a parent-focused component that provides detailed tracking of swim skills and delivers messaging targeting perceptions of children's drowning risk and supervision needs may serve to maximize the drowning protection afforded by these programs. Delivering messaging in the form of 'close-call' drowning stories may prove especially effective to impact parents' supervision practices in drowning risk situations. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Underwater noise from three types of offshore wind turbines: estimation of impact zones for harbor porpoises and harbor seals.

    Science.gov (United States)

    Tougaard, Jakob; Henriksen, Oluf Damsgaard; Miller, Lee A

    2009-06-01

    Underwater noise was recorded from three different types of wind turbines in Denmark and Sweden (Middelgrunden, Vindeby, and Bockstigen-Valar) during normal operation. Wind turbine noise was only measurable above ambient noise at frequencies below 500 Hz. Total sound pressure level was in the range 109-127 dB re 1 microPa rms, measured at distances between 14 and 20 m from the foundations. The 1/3-octave noise levels were compared with audiograms of harbor seals and harbor porpoises. Maximum 1/3-octave levels were in the range 106-126 dB re 1 microPa rms. Maximum range of audibility was estimated under two extreme assumptions on transmission loss (3 and 9 dB per doubling of distance, respectively). Audibility was low for harbor porpoises extending 20-70 m from the foundation, whereas audibility for harbor seals ranged from less than 100 m to several kilometers. Behavioral reactions of porpoises to the noise appear unlikely except if they are very close to the foundations. However, behavioral reactions from seals cannot be excluded up to distances of a few hundred meters. It is unlikely that the noise reaches dangerous levels at any distance from the turbines and the noise is considered incapable of masking acoustic communication by seals and porpoises.

  1. The swimming polarity of multicellular magnetotactic prokaryotes can change during an isolation process employing magnets: evidence of a relation between swimming polarity and magnetic moment intensity.

    Science.gov (United States)

    de Melo, Roger Duarte; Acosta-Avalos, Daniel

    2017-09-01

    Magnetotactic microorganisms are characterized by swimming in the direction of an applied magnetic field. In nature, two types of swimming polarity have been observed: north-seeking microorganisms that swim in the same direction as the magnetic field, and south-seeking microorganisms that swim in the opposite direction. The present work studies the reversal in the swimming polarity of the multicellular magnetotactic prokaryote Candidatus Magnetoglobus multicellularis following an isolation process using high magnetic fields from magnets. The proportion of north- and south-seeking organisms was counted as a function of the magnetic field intensity used during the isolation of the organisms from sediment. It was observed that the proportion of north-seeking organisms increased when the magnetic field was increased. The magnetic moment for north- and south-seeking populations was estimated using the U-turn method. The average magnetic moment was higher for north- than south-seeking organisms. The results suggest that the reversal of swimming polarity must occur during the isolation process in the presence of high magnetic fields and magnetic field gradients. It is shown for the first time that the swimming polarity reversal depends on the magnetic moment intensity of multicellular magnetotactic prokaryotes, and new studies must be undertaken to understand the role of magnetic moment polarity and oxygen gradients in determination of swimming polarity.

  2. The Shark Random Swim - (Lévy Flight with Memory)

    Science.gov (United States)

    Businger, Silvia

    2018-05-01

    The Elephant Random Walk (ERW), first introduced by Schütz and Trimper (Phys Rev E 70:045101, 2004), is a one-dimensional simple random walk on Z having a memory about the whole past. We study the Shark Random Swim, a random walk with memory about the whole past, whose steps are α -stable distributed with α \\in (0,2] . Our aim in this work is to study the impact of the heavy tailed step distributions on the asymptotic behavior of the random walk. We shall see that, as for the ERW, the asymptotic behavior of the Shark Random Swim depends on its memory parameter p, and that a phase transition can be observed at the critical value p=1/α.

  3. Indoor swimming pools. Humidity caused problems and suggested solutions

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    Reports have been received from across Canada on premature deterioration and other problems of indoor swimming pool buildings. This technical paper has been prepared to assist pool managers to solve these problems, which typically include leaking roofs, condensation on inside walls, peeling paint, efflorescence, rusting of metal elements, deterioration of concrete block structures, and high costs for pool heating. An effective insulation and vapor barrier system for a swimming pool roof is described, and the high relative humidity of the typical pool building is discussed as the primary cause of most problems. Proper sealing to cut down air infiltration is recommended, along with proper maintenance and painting. High energy costs are often due to low insulation values and to excessive ventilation used for decreasing the humidity. By using dehumidifiers capable of heat recovery, and by placing an insulating blanket on the pool after operating hours, it is shown that substantial cost savings are possible. 10 figs.

  4. North Sea ecosystem change from swimming crabs to seagulls.

    Science.gov (United States)

    Luczak, C; Beaugrand, G; Lindley, J A; Dewarumez, J-M; Dubois, P J; Kirby, R R

    2012-10-23

    A recent increase in sea temperature has established a new ecosystem dynamic regime in the North Sea. Climate-induced changes in decapods have played an important role. Here, we reveal a coincident increase in the abundance of swimming crabs and lesser black-backed gull colonies in the North Sea, both in time and in space. Swimming crabs are an important food source for lesser black-backed gulls during the breeding season. Inhabiting the land, but feeding mainly at sea, lesser black-backed gulls provide a link between marine and terrestrial ecosystems, since the bottom-up influence of allochthonous nutrient input from seabirds to coastal soils can structure the terrestrial food web. We, therefore, suggest that climate-driven changes in trophic interactions in the marine food web may also have ensuing ramifications for the coastal ecology of the North Sea.

  5. Development of a Simulation Model for Swimming with Diving Fins

    Directory of Open Access Journals (Sweden)

    Motomu Nakashima

    2018-02-01

    Full Text Available The simulation model to assess the performance of diving fin was developed by extending the swimming human simulation model SWUM. A diving fin was modeled as a series of five rigid plates and connected to the human model by springs and dampers. These plates were connected to each other by virtual springs and dampers, and fin’s bending property was represented by springs and dampers as well. An actual diver’s swimming motion with fins was acquired by a motion capture experiment. In order to determine the bending property of the fin, two bending tests on land were conducted. In addition, an experiment was conducted in order to determine the fluid force coefficients in the fluid force model for the fin. Finally, using all measured and identified information, a simulation, in which the experimental situation was reproduced, was carried out. It was confirmed that the diver in the simulation propelled forward in the water successfully.

  6. Multidisciplinary teaching in swimming: methodological reflection and proposal of check list

    Directory of Open Access Journals (Sweden)

    Sofia Canossa

    2007-12-01

    Full Text Available The present study proposes a new multidisciplinary approach related to teaching in swimming. Swimming is an interdisciplinary physical activity, which can be truly important at the level of the motor learning and experimentation in aquatic activities. In the present manuscript, it was compared the present reality of teaching in Swimming with a new perspective, this one with a multidisciplinary scope. Following the referred analysis, it was presented a discussion about the orientation and adequacy of the contents of the Swimming curriculum for children and youngsters, which are populations with specific characteristics and development necessities. In this sense, after stating the relevance of a multidisciplinary perspective, it was proposed a new approach for basic aquatic motor skills acquisition based on four disciplines: swimming, water polo, synchronised swimming and platform diving. This was made taking into account the initial stage of swimming teaching, i.e., aquatic readiness. This proposal aims mainly at implementing the teaching of Swimming at a multidisciplinary point of view that, in our opinion, is urgent, namely due to the small expression that the aquatic modalities traditionally considered as swimming satellites (water polo, synchronised swimming and platform diving have in the Portuguese sports context.

  7. Presence and select determinants of organophosphate flame retardants in public swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Teo, Tiffany L.L., E-mail: tiffany.teo@unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Kensington NSW 2052 (Australia); Coleman, Heather M., E-mail: h.coleman@ulster.ac.uk [Nanotechnology and Integrated BioEngineering Centre, School of Engineering, University of Ulster, Jordanstown, County Antrim BT37 0QB, Northern Ireland (United Kingdom); Khan, Stuart J., E-mail: s.khan@unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Kensington NSW 2052 (Australia)

    2016-11-01

    The occurrence of five organophosphate flame retardants (PFRs) consisting of tributyl phosphate (TNBP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1.3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) in swimming pools were investigated. Fifteen chlorinated public swimming pools were sampled, including indoor pools, outdoor pools and spa pools. The analyses were carried out using isotope dilution gas chromatography tandem mass spectrometry. All five PFRs were detected in swimming pool waters with concentrations ranging from 5–27 ng/L (TNBP), 7–293 ng/L (TCEP), 62–1180 ng/L (TCIPP), 10–670 ng/L (TDCIPP) and 8–132 ng/L (TPHP). The concentrations of PFRs were generally higher in indoor swimming pools compared to outdoor swimming pools. In municipal water supplies, used to fill the swimming pools in three of the sampling locations, the five PFRs were all below the limit of quantifications, eliminating this as the source. Potential leaching of PFRs from commonly used swimming equipment, including newly purchased kickboards and swimsuits was investigated. These experiments revealed that PFRs leached from swimsuits, and may be a source of PFRs in swimming pools. A quantitative risk assessment revealed that the health risk to PFRs via swimming pools was generally low and below commonly applied health risk benchmarks. - Highlights: • TNBP, TCEP, TCIPP, TDCIPP and TPHP were detected in chlorinated swimming pools. • PFRs were below the LOQ in fill water samples collected from 3 locations. • TCIPP was observed to have the highest concentrations in swimming pools. • PFRs are leaching from swimsuits and may be a source in swimming pools. • Health risks through oral and dermal exposure to PFRs in swimming pools were low.

  8. Presence and select determinants of organophosphate flame retardants in public swimming pools

    International Nuclear Information System (INIS)

    Teo, Tiffany L.L.; Coleman, Heather M.; Khan, Stuart J.

    2016-01-01

    The occurrence of five organophosphate flame retardants (PFRs) consisting of tributyl phosphate (TNBP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1.3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) in swimming pools were investigated. Fifteen chlorinated public swimming pools were sampled, including indoor pools, outdoor pools and spa pools. The analyses were carried out using isotope dilution gas chromatography tandem mass spectrometry. All five PFRs were detected in swimming pool waters with concentrations ranging from 5–27 ng/L (TNBP), 7–293 ng/L (TCEP), 62–1180 ng/L (TCIPP), 10–670 ng/L (TDCIPP) and 8–132 ng/L (TPHP). The concentrations of PFRs were generally higher in indoor swimming pools compared to outdoor swimming pools. In municipal water supplies, used to fill the swimming pools in three of the sampling locations, the five PFRs were all below the limit of quantifications, eliminating this as the source. Potential leaching of PFRs from commonly used swimming equipment, including newly purchased kickboards and swimsuits was investigated. These experiments revealed that PFRs leached from swimsuits, and may be a source of PFRs in swimming pools. A quantitative risk assessment revealed that the health risk to PFRs via swimming pools was generally low and below commonly applied health risk benchmarks. - Highlights: • TNBP, TCEP, TCIPP, TDCIPP and TPHP were detected in chlorinated swimming pools. • PFRs were below the LOQ in fill water samples collected from 3 locations. • TCIPP was observed to have the highest concentrations in swimming pools. • PFRs are leaching from swimsuits and may be a source in swimming pools. • Health risks through oral and dermal exposure to PFRs in swimming pools were low.

  9. Simulated front crawl swimming performance related to critical speed and critical power.

    Science.gov (United States)

    Toussaint, H M; Wakayoshi, K; Hollander, A P; Ogita, F

    1998-01-01

    Competitive pool swimming events range in distance from 50 to 1500 m. Given the difference in performance times (+/- 23-1000 s), the contribution of the aerobic and anaerobic energy systems changes considerably with race distance. In training practice the regression line between swimming distance and time (Distance = critical velocity x time + anaerobic swimming capacity) is used to determine the individual capacity of the aerobic and anaerobic metabolic pathways. Although there is confidence that critical velocity and anaerobic swimming capacity are fitness measures that separate aerobic and anaerobic components, a firm theoretical basis for the interpretation of these results does not exist. The purpose of this study was to evaluate the critical power concept and anaerobic swimming capacity as measures of the aerobic and anaerobic capacity using a modeling approach. A systems model was developed that relates the mechanics and energetics involved in front crawl swimming performance. From actual swimming flume measurements, the time dependent aerobic and anaerobic energy release was modeled. Data derived from the literature were used to relate the energy cost of front crawl swimming to swimming velocity. A balance should exist between the energy cost to swim a distance in a certain time and the concomitant aerobic and anaerobic energy release. The ensuing model was used to predict performance times over a range of distances (50-1500 m) and to calculate the regression line between swimming distance and time. Using a sensitivity analysis, it was demonstrated that the critical velocity is indicative for the capacity of the aerobic energy system. Estimates of the anaerobic swimming capacity, however, were influenced by variations in both anaerobic and aerobic energy release. Therefore, it was concluded that the anaerobic swimming capacity does not provide a reliable estimate of the anaerobic capacity.

  10. Biochemical and hematological changes following the 120-km open-water marathon swim.

    Science.gov (United States)

    Drygas, Wojciech; Rębowska, Ewa; Stępień, Ewa; Golański, Jacek; Kwaśniewska, Magdalena

    2014-09-01

    Data on physiological effects and potential risks of a ultraendurance swimming are scarce. This report presents the unique case of a 61-year old athlete who completed a non-stop open-water 120-km ultramarathon swim on the Warta River, Poland. Pre-swimming examinations revealed favorable conditions (blood pressure, 110/70 mmHg; rest heart rate, 54 beats/minute, ejection fraction, 60%, 20.2 metabolic equivalents in a maximal exercise test). The swimming time and distance covered were 27 h 33 min and 120 km, respectively. Blood samples for hematological and biochemical parameters were collected 30 min, 4 hrs, 10 hrs and 8 days after the swim. The body temperature of the swimmer was 36.7°C before and 35.1°C after the swim. The hematological parameters remained within the reference range in the postexercise period except for leucocytes (17.5 and 10.6 x G/l noted 30 minutes and 4 hours after the swim, respectively). Serum urea, aspartate aminotransferase and C-reactive protein increased above the reference range reaching 11.3 mmol/l, 1054 nmol/l/s and 25.9 mg/l, respectively. Symptomatic hyponatremia was not observed. Although the results demonstrate that an experienced athlete is able to complete an ultra-marathon swim without negative health consequences, further studies addressing the potential risks of marathon swimming are required. Key pointsData on biochemical changes due to long-distance swimming are scarce.This report presents the unique case of a 61-year old athlete who completed a non-stop open-water 120-km ultramarathon swim.An experienced athlete is able to complete an ultra-marathon swim without serious health consequences.Regarding the growing popularity of marathon swimming further studies addressing the potential risks of such exhaustive exercise are required.

  11. Resolving shifting patterns of muscle energy use in swimming fish.

    Directory of Open Access Journals (Sweden)

    Shannon P Gerry

    Full Text Available Muscle metabolism dominates the energy costs of locomotion. Although in vivo measures of muscle strain, activity and force can indicate mechanical function, similar muscle-level measures of energy use are challenging to obtain. Without this information locomotor systems are essentially a black box in terms of the distribution of metabolic energy. Although in situ measurements of muscle metabolism are not practical in multiple muscles, the rate of blood flow to skeletal muscle tissue can be used as a proxy for aerobic metabolism, allowing the cost of particular muscle functions to be estimated. Axial, undulatory swimming is one of the most common modes of vertebrate locomotion. In fish, segmented myotomal muscles are the primary power source, driving undulations of the body axis that transfer momentum to the water. Multiple fins and the associated fin muscles also contribute to thrust production, and stabilization and control of the swimming trajectory. We have used blood flow tracers in swimming rainbow trout (Oncorhynchus mykiss to estimate the regional distribution of energy use across the myotomal and fin muscle groups to reveal the functional distribution of metabolic energy use within a swimming animal for the first time. Energy use by the myotomal muscle increased with speed to meet thrust requirements, particularly in posterior myotomes where muscle power outputs are greatest. At low speeds, there was high fin muscle energy use, consistent with active stability control. As speed increased, and fins were adducted, overall fin muscle energy use declined, except in the caudal fin muscles where active fin stiffening is required to maintain power transfer to the wake. The present data were obtained under steady-state conditions which rarely apply in natural, physical environments. This approach also has potential to reveal the mechanical factors that underlie changes in locomotor cost associated with movement through unsteady flow regimes.

  12. Resolving Shifting Patterns of Muscle Energy Use in Swimming Fish

    Science.gov (United States)

    Gerry, Shannon P.; Ellerby, David J.

    2014-01-01

    Muscle metabolism dominates the energy costs of locomotion. Although in vivo measures of muscle strain, activity and force can indicate mechanical function, similar muscle-level measures of energy use are challenging to obtain. Without this information locomotor systems are essentially a black box in terms of the distribution of metabolic energy. Although in situ measurements of muscle metabolism are not practical in multiple muscles, the rate of blood flow to skeletal muscle tissue can be used as a proxy for aerobic metabolism, allowing the cost of particular muscle functions to be estimated. Axial, undulatory swimming is one of the most common modes of vertebrate locomotion. In fish, segmented myotomal muscles are the primary power source, driving undulations of the body axis that transfer momentum to the water. Multiple fins and the associated fin muscles also contribute to thrust production, and stabilization and control of the swimming trajectory. We have used blood flow tracers in swimming rainbow trout (Oncorhynchus mykiss) to estimate the regional distribution of energy use across the myotomal and fin muscle groups to reveal the functional distribution of metabolic energy use within a swimming animal for the first time. Energy use by the myotomal muscle increased with speed to meet thrust requirements, particularly in posterior myotomes where muscle power outputs are greatest. At low speeds, there was high fin muscle energy use, consistent with active stability control. As speed increased, and fins were adducted, overall fin muscle energy use declined, except in the caudal fin muscles where active fin stiffening is required to maintain power transfer to the wake. The present data were obtained under steady-state conditions which rarely apply in natural, physical environments. This approach also has potential to reveal the mechanical factors that underlie changes in locomotor cost associated with movement through unsteady flow regimes. PMID:25165858

  13. A swimming pool array for ultra high energy showers

    Science.gov (United States)

    Yodh, Gaurang B.; Shoup, Anthony; Barwick, Steve; Goodman, Jordan A.

    1992-11-01

    A very preliminary design concept for an array using water Cherenkov counters, built out of commercially available backyard swimming pools, to sample the electromagnetic and muonic components of ultra high energy showers at large lateral distances is presented. The expected performance of the pools is estimated using the observed lateral distributions by scintillator and water Cherenkov arrays at energies above 1019 eV and simulations.

  14. Unsteady turbulent boundary layers in swimming rainbow trout.

    Science.gov (United States)

    Yanase, Kazutaka; Saarenrinne, Pentti

    2015-05-01

    The boundary layers of rainbow trout, Oncorhynchus mykiss, swimming at 1.02±0.09 L s(-1) (mean±s.d., N=4), were measured by the particle image velocimetry (PIV) technique at a Reynolds number of 4×10(5). The boundary layer profile showed unsteadiness, oscillating above and beneath the classical logarithmic law of the wall with body motion. Across the entire surface regions that were measured, local Reynolds numbers based on momentum thickness, which is the distance that is perpendicular to the fish surface through which the boundary layer momentum flows at free-stream velocity, were greater than the critical value of 320 for the laminar-to-turbulent transition. The skin friction was dampened on the convex surface while the surface was moving towards a free-stream flow and increased on the concave surface while retreating. These observations contradict the result of a previous study using different species swimming by different methods. Boundary layer compression accompanied by an increase in local skin friction was not observed. Thus, the overall results may not support absolutely the Bone-Lighthill boundary layer thinning hypothesis that the undulatory motions of swimming fish cause a large increase in their friction drag because of the compression of the boundary layer. In some cases, marginal flow separation occurred on the convex surface in the relatively anterior surface region, but the separated flow reattached to the fish surface immediately downstream. Therefore, we believe that a severe impact due to induced drag components (i.e. pressure drag) on the swimming performance, an inevitable consequence of flow separation, was avoided. © 2015. Published by The Company of Biologists Ltd.

  15. Aerial Survey Counts of Harbor Seals in Coastal Alaska (2003-2011)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset supports efforts to estimate the abundance and trends in population size of Alaska harbor seals. Annual surveys of harbor seal populations are...

  16. Aerial Survey Counts of Harbor Seals in Coastal Alaska (1998-2002)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset supports efforts to estimate the abundance and trends in population size of Alaska harbor seals. Annual surveys of harbor seal populations are...

  17. A Comprehensive Copper Compliance Strategy: Implementing Regulatory Guidance at Pearl Harbor Naval Shipyard & Intermediate Maintenance Facility

    National Research Council Canada - National Science Library

    Earley, P. J; Rosen, G; Rivera-Duarte, I; Gauthier, R. D; Arias-Thode, Y; Thompson, J; Swope, B

    2007-01-01

    Studies were performed to develop a new National Pollution Discharge Elimination Systems Permit for the discharge of effluents from the Pearl Harbor Naval Shipyard and Intermediate Maintenance Facility into Pearl Harbor...

  18. Telemetry data from satellite tags deployed on harbor seals in Cook Inlet, Alaska

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Between 2004 and 2006 we conducted four harbor seal tagging trips in Cook Inlet during the months of October and May. In total, we captured and released 93 harbor...

  19. A turbulence-induced switch in phytoplankton swimming behavior

    Science.gov (United States)

    Carrara, Francesco; Sengupta, Anupam; Stocker, Roman

    2015-11-01

    Phytoplankton, unicellular photosynthetic organisms that form the basis of life in aquatic environments, are frequently exposed to turbulence, which has long been known to affect phytoplankton fitness and species succession. Yet, mechanisms by which phytoplankton may adapt to turbulence have remained unknown. Here we present a striking behavioral response of a motile species - the red-tide-producing raphidophyte Heterosigma akashiwo - to hydrodynamic cues mimicking those experienced in ocean turbulence. In the absence of turbulence, H. akashiwo exhibits preferential upwards swimming (`negative gravitaxis'), observable as a strong accumulation of cells at the top of an experimental container. When cells were exposed to overturning in an automated chamber - representing a minimum experimental model of rotation by Kolmogorov-scale turbulent eddies - the population robustly split in two nearly equi-abundant subpopulations, one swimming upward and one swimming downward. Microscopic observations at the single-cell level showed that the behavioral switch was accompanied by a rapid morphological change. A mechanistic model that takes into account cell shape confirms that modulation of morphology can alter the hydrodynamic stress distribution over the cell body, which, in turn, triggers the observed switch in phytoplankton migration direction. This active response to fluid flow, whereby microscale morphological changes influence ocean-scale migration dynamics, could be part of a bet-hedging strategy to maximize the chances of at least a fraction of the population evading high-turbulence microzones.

  20. Diagnosis of Swimming Induced Pulmonary Edema—A Review

    Science.gov (United States)

    Grünig, Hannes; Nikolaidis, Pantelis T.; Moon, Richard E.; Knechtle, Beat

    2017-01-01

    Swimming induced pulmonary edema (SIPE) is a complication that can occur during exercise with the possibility of misdiagnosis and can quickly become life threatening; however, medical literature infrequently describes SIPE. Therefore, the aim of this review was to analyse all individual cases diagnosed with SIPE as reported in scientific sources, with an emphasis on the diagnostic pathways and the key facts resulting in its diagnosis. Due to a multifactorial and complicated pathophysiology, the diagnosis could be difficult. Based on the actual literature, we try to point out important findings regarding history, conditions, clinical findings, and diagnostic testing helping to confirm the diagnosis of SIPE. Thirty-eight cases from seventeen articles reporting the diagnosis of SIPE were selected. We found remarkable differences in the individual described diagnostic pathways. A total of 100% of the cases suffered from an acute onset of breathing problems, occasionally accompanied by hemoptysis. A total of 73% showed initial hypoxemia. In most of the cases (89%), an initial chest X-Ray or chest CT was available, of which one-third (71%) showed radiological signs of pulmonary edema. The majority of the cases (82%) experienced a rapid resolution of symptoms within 48 h, the diagnostic hallmark of SIPE. Due to a foreseeable increase in participation in swimming competitions and endurance competitions with a swimming component, diagnosis of SIPE will be important, especially for medical teams caring for these athletes. PMID:28912730

  1. Fluid mechanics of swimming bacteria with multiple flagella.

    Science.gov (United States)

    Kanehl, Philipp; Ishikawa, Takuji

    2014-04-01

    It is known that some kinds of bacteria swim by forming a bundle of their multiple flagella. However, the details of flagella synchronization as well as the swimming efficiency of such bacteria have not been fully understood. In this study, swimming of multiflagellated bacteria is investigated numerically by the boundary element method. We assume that the cell body is a rigid ellipsoid and the flagella are rigid helices suspended on flexible hooks. Motors apply constant torque to the hooks, rotating the flagella either clockwise or counterclockwise. Rotating all flagella clockwise, bundling of all flagella is observed in every simulated case. It is demonstrated that the counter rotation of the body speeds up the bundling process. During this procedure the flagella synchronize due to hydrodynamic interactions. Moreover, the results illustrated that during running the multiflagellated bacterium shows higher propulsive efficiency (distance traveled per one flagellar rotation) over a bacterium with a single thick helix. With an increasing number of flagella the propulsive efficiency increases, whereas the energetic efficiency decreases, which indicates that efficiency is something multiflagellated bacteria are assigning less priority to than to motility. These findings form a fundamental basis in understanding bacterial physiology and metabolism.

  2. Hydrodynamic role of longitudinal ridges in a leatherback turtle swimming

    Science.gov (United States)

    Bang, Kyeongtae; Kim, Jooha; Lee, Sang-Im; Choi, Haecheon

    2015-11-01

    The leatherback sea turtle (Dermochelys coriacea), the fastest swimmer and the deepest diver among marine turtles, has five longitudinal ridges on its carapace. These ridges are the most remarkable morphological features distinguished from other marine turtles. To investigate the hydrodynamic role of these ridges in the leatherback turtle swimming, we model a carapace with and without ridges by using three dimensional surface data of a stuffed leatherback turtle in the National Science Museum, Korea. The experiment is conducted in a wind tunnel in the ranges of the real leatherback turtle's Reynolds number (Re) and angle of attack (α). The longitudinal ridges function differently according to the flow condition (i.e. Re and α). At low Re and negative α that represent the swimming condition of hatchlings and juveniles, the ridges significantly decrease the drag by generating streamwise vortices and delaying the main separation. On the other hand, at high Re and positive α that represent the swimming condition of adults, the ridges suppress the laminar separation bubble near the front part by generating streamwise vortices and enhance the lift and lift-to-drag ratio. Supported by the NRF program (2011-0028032).

  3. Does Helicobacter pylori exhibit corkscrew motion while swimming?

    Science.gov (United States)

    Constantino, Maira; Hardcastle, Joseph; Bansil, Rama

    2015-03-01

    Helicobacter pylori is a spiral shaped bacterium associated with ulcers, gastric cancer, gastritis among other diseases. In order to colonize the harsh acidic environment of the stomach H. pylori has to go across the viscoelastic mucus layer of the stomach. Many studies have been conducted on the swimming of H. pylori in viscous media however none have taken into account the influence of cell-body shape on the trajectory. We present an experimental study of the effects of body shape in the swimming trajectory of H. pylori in viscous media by a quantitative analysis of the bacterium rotation and translation in gels using phase contrast microscopy and particle tracking techniques. Preliminary microscopic tracking measurements show very well defined helical trajectories in the spiral-shaped wild type H. pylori. These helical trajectories are not seen in rod-shaped mutants which sometimes display whirling motion about one end acting as a hinge. We will present an analysis of the different trajectories for bacteria swimming in media with different viscoelastic parameters. Supported by the National Science Foundation PHY PoLS.

  4. Disinfection Methods for Swimming Pool Water: Byproduct Formation and Control

    Directory of Open Access Journals (Sweden)

    Huma Ilyas

    2018-06-01

    Full Text Available This paper presents a comprehensive and critical comparison of 10 disinfection methods of swimming pool water: chlorination, electrochemically generated mixed oxidants (EGMO, ultraviolet (UV irradiation, UV/chlorine, UV/hydrogen peroxide (H2O2, UV/H2O2/chlorine, ozone (O3/chlorine, O3/H2O2/chlorine, O3/UV and O3/UV/chlorine for the formation, control and elimination of potentially toxic disinfection byproducts (DBPs: trihalomethanes (THMs, haloacetic acids (HAAs, haloacetonitriles (HANs, trihaloacetaldehydes (THAs and chloramines (CAMs. The statistical comparison is carried out using data on 32 swimming pools accumulated from the reviewed studies. The results indicate that O3/UV and O3/UV/chlorine are the most promising methods, as the concentration of the studied DBPs (THMs and HANs with these methods was reduced considerably compared with chlorination, EGMO, UV irradiation, UV/chlorine and O3/chlorine. However, the concentration of the studied DBPs including HAAs and CAMs remained much higher with O3/chlorine compared with the limits set by the WHO for drinking water quality. Moreover, the enhancement in the formation of THMs, HANs and CH with UV/chlorine compared with UV irradiation and the increase in the level of HANs with O3/UV/chlorine compared with O3/UV indicate the complexity of the combined processes, which should be optimized to control the toxicity and improve the quality of swimming pool water.

  5. Unsteady flow phenomena in human undulatory swimming: a numerical approach.

    Science.gov (United States)

    Pacholak, Steffen; Hochstein, Stefan; Rudert, Alexander; Brücker, Christoph

    2014-06-01

    The undulatory underwater sequence is one of the most important phases in competitive swimming. An understanding of the recurrent vortex dynamics around the human body and their generation could therefore be used to improve swimming techniques. In order to produce a dynamic model, we applied human joint kinematics to three-dimensional (3D) body scans of a female swimmer. The flow around this dynamic model was then calculated using computational fluid dynamics with the aid of moving 3D meshes. Evaluation of the numerical results delivered by the various motion cycles identified characteristic vortex structures for each of the cycles, which exhibited increasing intensity and drag influence. At maximum thrust, drag forces appear to be 12 times higher than those of a passive gliding swimmer. As far as we know, this is the first disclosure of vortex rings merging into vortex tubes in the wake after vortex recapturing. All unsteady structures were visualized using a modified Q-criterion also incorporated into our methods. At the very least, our approach is likely to be suited to further studies examining swimmers engaging in undulatory swimming during training or competition.

  6. The backstroke swimming start: state of the art.

    Science.gov (United States)

    de Jesus, Karla; de Jesus, Kelly; Fernandes, Ricardo J; Vilas-Boas, João Paulo; Sanders, Ross

    2014-09-29

    As sprint swimming events can be decided by margins as small as .01 s, thus, an effective start is essential. This study reviews and discusses the 'state of the art' literature regarding backstroke start biomechanics from 23 documents. These included two swimming specific publications, eight peer-reviewed journal articles, three from the Biomechanics and Medicine in Swimming Congress series, eight from the International Society of Biomechanics in Sports Conference Proceedings, one from a Biomechanics Congress and one academic (PhD) thesis. The studies had diverse aims, including swimmers' proficiency levels and data collection settings. There was no single consensus for defining phase descriptions; and kinematics, kinetics and EMG approaches were implemented in laboratory settings. However, researchers face great challenges in improving methods of quantifying valid, reliable and accurate data between laboratory and competition conditions. For example, starting time was defined from the starting signal to distances as disparate as ∼5 m to 22.86 m in several studies. Due to recent rule changes, some of the research outcomes now refer to obsolete backstroke start techniques, and only a few studies considered the actual international rules. This literature review indicated that further research is required, in both laboratory and competition settings focusing on the combined influences of the current rules and block configuration on backstroke starting performances.

  7. Effects of altered gravity on the swimming behaviour of fish

    Science.gov (United States)

    Hilbig, R.; Anken, R. H.; Sonntag, G.; Höhne, S.; Henneberg, J.; Kretschmer, N.; Rahmann, H.

    Humans taking part in parabolic aircraft flights (PAFs) may suffer from space motion sickness-phenomena (SMS, a kinetosis). It has been argued that SMS during PAFs might not be based on microgravity alone but rather on changing accelerations from 0g to 2g. We test here the hypothesis that PAF-induced kinetosis is based on asymmetric statoliths (i.e., differently weighed statoliths on the right and the left side of the head), with asymmetric inputs to the brain being disclosed at microgravity. Since fish frequently reveal kinetotic behaviour during PAFs (especially so-called spinning movements and looping responses), we investigated (1) whether or not kinetotically swimming fish at microgravity would have a pronounced inner ear otolith asymmetry and (2) whether or not slow translational and continuously changing linear (vertical) acceleration on ground induced kinetosis. These latter accelerations were applied using a specially developed parabel-animal-container (PAC) to stimulate the cupular organs. The results suggest that the fish tested on ground can counter changing accelerations successfully without revealing kinetotic swimming patterns. Kinetosis could only be induced by PAFs. This finding suggests that it is indeed microgravity rather than changing accelerations, which induces kinetosis. Moreover, we demonstrate that fish swimming kinetotically during PAFs correlates with a higher otolith asymmetry in comparison to normally behaving animals in PAFs.

  8. A swimming robot actuated by living muscle tissue

    Directory of Open Access Journals (Sweden)

    Herr Hugh

    2004-10-01

    Full Text Available Abstract Biomechatronics is the integration of biological components with artificial devices, in which the biological component confers a significant functional capability to the system, and the artificial component provides specific cellular and tissue interfaces that promote the maintenance and functional adaptation of the biological component. Based upon functional performance, muscle is potentially an excellent mechanical actuator, but the larger challenge of developing muscle-actuated, biomechatronic devices poses many scientific and engineering challenges. As a demonstratory proof of concept, we designed, built, and characterized a swimming robot actuated by two explanted frog semitendinosus muscles and controlled by an embedded microcontroller. Using open loop stimulation protocols, the robot performed basic swimming maneuvers such as starting, stopping, turning (turning radius ~400 mm and straight-line swimming (max speed >1/3 body lengths/second. A broad spectrum antibiotic/antimycotic ringer solution surrounded the muscle actuators for long term maintenance, ex vivo. The robot swam for a total of 4 hours over a 42 hour lifespan (10% duty cycle before its velocity degraded below 75% of its maximum. The development of functional biomechatronic prototypes with integrated musculoskeletal tissues is the first critical step toward the long term objective of controllable, adaptive and robust biomechatronic robots and prostheses.

  9. Coordination of multiple appendages in drag-based swimming.

    Science.gov (United States)

    Alben, Silas; Spears, Kevin; Garth, Stephen; Murphy, David; Yen, Jeannette

    2010-11-06

    Krill are aquatic crustaceans that engage in long distance migrations, either vertically in the water column or horizontally for 10 km (over 200,000 body lengths) per day. Hence efficient locomotory performance is crucial for their survival. We study the swimming kinematics of krill using a combination of experiment and analysis. We quantify the propulsor kinematics for tethered and freely swimming krill in experiments, and find kinematics that are very nearly metachronal. We then formulate a drag coefficient model which compares metachronal, synchronous and intermediate motions for a freely swimming body with two legs. With fixed leg velocity amplitude, metachronal kinematics give the highest average body speed for both linear and quadratic drag laws. The same result holds for five legs with the quadratic drag law. When metachronal kinematics is perturbed towards synchronous kinematics, an analysis shows that the velocity increase on the power stroke is outweighed by the velocity decrease on the recovery stroke. With fixed time-averaged work done by the legs, metachronal kinematics again gives the highest average body speed, although the advantage over synchronous kinematics is reduced.

  10. Physical and energy requirements of competitive swimming events.

    Science.gov (United States)

    Pyne, David B; Sharp, Rick L

    2014-08-01

    The aquatic sports competitions held during the summer Olympic Games include diving, open-water swimming, pool swimming, synchronized swimming, and water polo. Elite-level performance in each of these sports requires rigorous training and practice to develop the appropriate physiological, biomechanical, artistic, and strategic capabilities specific to each sport. Consequently, the daily training plans of these athletes are quite varied both between and within the sports. Common to all aquatic athletes, however, is that daily training and preparation consumes several hours and involves frequent periods of high-intensity exertion. Nutritional support for this high-level training is a critical element of the preparation of these athletes to ensure the energy and nutrient demands of the training and competition are met. In this article, we introduce the fundamental physical requirements of these sports and specifically explore the energetics of human locomotion in water. Subsequent articles in this issue explore the specific nutritional requirements of each aquatic sport. We hope that such exploration will provide a foundation for future investigation of the roles of optimal nutrition in optimizing performance in the aquatic sports.

  11. Mathematical modeling of the energy consumption of heated swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Le Bel, C.; Millette, J. [LTE Shawinigan, Shawinigan, PQ (Canada)

    2007-07-01

    A mathematical model was developed to estimate the water temperature of a residential swimming pool. The model can compare 2 different situations and, if local climatic conditions are known, it can accurately predict energy costs of the pool relative to the total energy consumption of the house. When used with the appropriate energy transfer coefficient and weather file, the model can estimate the water temperature of a residential swimming pool having specific characteristics, such as in-ground, above-ground, heated or non-heated. The model is suitable for determining residential loads. It can be applied to different pool types and sizes, for different water heating scenarios and different climatic regions. Data obtained from the monitoring of water temperature and electricity use of 57 residential swimming pools was used to validate the model. In addition, 5 above-ground pools were installed on the property of LTE Shawinigan to allow for a more detailed study of the parameters involved in the thermal balance of a pool. The mathematical model, based on a global heat transfer coefficient, can determine the effect of a solar blanket and the effect of water volume. 14 refs., 5 tabs., 11 figs.

  12. Social motivation and health in college club swimming.

    Science.gov (United States)

    Anderson, Austin R; Ramos, William D

    2018-03-22

    Participation in recreational sport clubs on campus is a popular student activity nationwide. These sport-based organizations provide a host of benefits within recognized dimensions of health and wellness. Understanding participants' motives for engaging in these types of activities can provide insight in design and delivery and enhance participant health. This study focuses on outcomes related to the social motivations for participation in a recreational sport swim club and their potential relationship to social health. Current members of recreational swimming clubs were contacted for participation in the study from March-April 2016. A Leisure Motivation Scale (LMS) survey was sent electronically to 196 collegiate swim clubs nationwide. Aggregate and multivariate analyses from 1011 responses were conducted to examine the social motivation and motivational differences of participants. Social motivations emerged as the predominate motivational construct, indicating important implications for social health improvement through participation. Demographically, results indicated no statistically significant differences in social motivation factors based on participant gender, and statistically significant differences within participant race, university affiliation and practice frequency. Impacts of these findings are important for practitioners and participants when evaluating the potential these programs have to influence participant social health.

  13. Quantitative flow analysis of swimming dynamics with coherent Lagrangian vortices.

    Science.gov (United States)

    Huhn, F; van Rees, W M; Gazzola, M; Rossinelli, D; Haller, G; Koumoutsakos, P

    2015-08-01

    Undulatory swimmers flex their bodies to displace water, and in turn, the flow feeds back into the dynamics of the swimmer. At moderate Reynolds number, the resulting flow structures are characterized by unsteady separation and alternating vortices in the wake. We use the flow field from simulations of a two-dimensional, incompressible viscous flow of an undulatory, self-propelled swimmer and detect the coherent Lagrangian vortices in the wake to dissect the driving momentum transfer mechanisms. The detected material vortex boundary encloses a Lagrangian control volume that serves to track back the vortex fluid and record its circulation and momentum history. We consider two swimming modes: the C-start escape and steady anguilliform swimming. The backward advection of the coherent Lagrangian vortices elucidates the geometry of the vorticity field and allows for monitoring the gain and decay of circulation and momentum transfer in the flow field. For steady swimming, momentum oscillations of the fish can largely be attributed to the momentum exchange with the vortex fluid. For the C-start, an additionally defined jet fluid region turns out to balance the high momentum change of the fish during the rapid start.

  14. Skin friction enhancement in a model problem of undulatory swimming

    Science.gov (United States)

    Ehrenstein, Uwe; Eloy, Christophe

    2013-10-01

    To calculate the energy costs of swimming, it is crucial to evaluate the drag force originating from skin friction. In this paper we examine the assumption, known as the 'Bone-Lighthill boundary-layer thinning hypothesis', that undulatory swimming motions induce a drag increase because of the compression of the boundary layer. Studying analytically an incoming flow along a flat plate moving at a normal velocity as a limit case of a yawed cylinder in uniform flow under the laminar boundary layer assumption, we demonstrate that the longitudinal drag scales as the square root of the normal velocity component. This analytical prediction is interpreted in the light of a three-dimensional numerical simulation result for a plate of finite length and width. An analogous two-dimensional Navier-Stokes problem by artificially accelerating the flow in a channel of finite height is proposed and solved numerically, showing the robustness of the analytical results. Solving the problem for an undulatory plate motion similar to fish swimming, we find a drag enhancement which can be estimated to be of the order of 20 %.

  15. A smart ROV solution for ship hull and harbor inspection

    Science.gov (United States)

    Reed, Scott; Wood, Jon; Vazquez, Jose; Mignotte, Pierre-Yves; Privat, Benjamin

    2010-04-01

    Hull and harbor infrastructure inspections are frequently performed manually and involve quite a bit of risk and human and monetary resources. In any kind of threat and resource constrained environment, this involves unacceptable levels of risk and cost. Modern Remotely Operated Vehicles are highly refined machines that provide features and capabilities previously unavailable. Operations once carried out by divers can now be carried out more quickly, efficiently and safely by smart enabled ROVs. ROVs are rapidly deployable and capable of continuous, reliable operations in adverse conditions. They also provide a stable platform on which multiple sensors may be mounted and utilized to meet the harbor inspection problem. Automated Control software provides ROV's and their pilots with the capability to inspect complex, constrained environments such as those found in a harbor region. This application and the user interface allow the ROV to automatically conduct complex maneuvers relative to the area being inspected and relieves the training requirements and work load for the pilot, allowing he or she to focus on the primary task of survey, inspection and looking for possible threats (such as IEDs, Limpet Mines, signs of sabotage, etc). Real-time sensor processing tools can be integrated into the smart ROV solution to assist the operator. Automatic Target Recognition (ATR) algorithms are used to search through the sensor data collected by the ROV in real time. These algorithms provide immediate feedback on possible threats and notify the operator of regions that may require manual verification. Sensor data (sonar or video) is also mosaiced, providing the operator with real-time situational awareness and a coverage map of the hull or seafloor. Detected objects may also be placed in the context of the large scale characteristics of the hull (or bottom or pilings) and localized. Within the complex areas such as the harbor pier pilings and the running gear of the ship, real

  16. 33 CFR 334.1430 - Apra Inner Harbor, Island of Guam; restricted area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Apra Inner Harbor, Island of Guam... THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1430 Apra Inner Harbor, Island of Guam; restricted area. (a) The restricted area. The waters within Apra Inner Harbor and...

  17. 33 CFR 165.1402 - Apra Outer Harbor, Guam-regulated navigation area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Apra Outer Harbor, Guam-regulated....1402 Apra Outer Harbor, Guam—regulated navigation area. (a) The following is a regulated navigation area—The waters of the Pacific Ocean and Apra Outer Harbor enclosed by a line beginning at latitude 13...

  18. 77 FR 45239 - Amendment of Class E Airspace; Bar Harbor, ME

    Science.gov (United States)

    2012-07-31

    ...-1366; Airspace Docket No. 11-ANE-13] Amendment of Class E Airspace; Bar Harbor, ME AGENCY: Federal... area at Bar Harbor, ME, as the Surry Non-Directional Radio Beacon (NDB) has been decommissioned and new Standard Instrument Approach Procedures have been developed at Hancock County-Bar Harbor Airport. This...

  19. 77 FR 27666 - Proposed Amendment of Class E Airspace; Bar Harbor, ME

    Science.gov (United States)

    2012-05-11

    ...-1366; Airspace Docket No. 11-ANE-13] Proposed Amendment of Class E Airspace; Bar Harbor, ME AGENCY... action proposes to amend Class E Airspace at Bar Harbor, ME, as the Surry Non-Directional Radio Beacon... Hancock County-Bar Harbor Airport. This action would enhance the safety and airspace management of...

  20. 33 CFR 162.165 - Buffalo and Rochester Harbors, New York.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Buffalo and Rochester Harbors, New York. 162.165 Section 162.165 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... and Rochester Harbors, New York. In Buffalo and Rochester Harbors, no vessel may exceed 6 miles per...

  1. 76 FR 32071 - Safety Zone; Conneaut Festival Fireworks, Conneaut Harbor, Conneaut, OH

    Science.gov (United States)

    2011-06-03

    ...-AA00 Safety Zone; Conneaut Festival Fireworks, Conneaut Harbor, Conneaut, OH AGENCY: Coast Guard, DHS... Conneaut Harbor, Conneaut, OH for the Conneaut Festival Fireworks. This zone is intended to restrict vessels from a portion of Conneaut Harbor, Conneaut, OH during the Conneaut Festival Fireworks on July 3...

  2. 78 FR 18479 - Drawbridge Operation Regulations; Inner Harbor Navigation Canal, New Orleans, LA

    Science.gov (United States)

    2013-03-27

    ... Operation Regulations; Inner Harbor Navigation Canal, New Orleans, LA AGENCY: Coast Guard, DHS. ACTION... across the Inner Harbor Navigation Canal, mile 4.6, at New Orleans, Louisiana. This deviation is... Seabrook Highway crossing the Inner Harbor Navigation Canal, mile 4.6, in New Orleans, Louisiana. The...

  3. 76 FR 38153 - California State Nonroad Engine Pollution Control Standards; Commercial Harbor Craft Regulations...

    Science.gov (United States)

    2011-06-29

    ... Standards; Commercial Harbor Craft Regulations; Opportunity for Public Hearing and Comment AGENCY... engines on commercial harbor craft. CARB has requested that EPA issue a new authorization under [email protected] . SUPPLEMENTARY INFORMATION: I. California's Commercial Harbor Craft Regulations In a...

  4. 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.

  5. Optimal swimming speed in head currents and effects on distance movement of winter-migrating fish

    DEFF Research Database (Denmark)

    Brodersen, J.; Nilsson, P.A.; Ammitzbøl, J.

    2008-01-01

    ecologically and economically important. We here use passive and active telemetry to study how winter migrating roach regulate swimming speed and distance travelled per day in response to variations in head current velocity. Furthermore, we provide theoretical predictions on optimal swimming speeds in head...... currents and relate these to our empirical results. We show that fish migrate farther on days with low current velocity, but travel at a greater ground speed on days with high current velocity. The latter result agrees with our predictions on optimal swimming speed in head currents, but disagrees...... with previously reported predictions suggesting that fish ground speed should not change with head current velocity. We suggest that this difference is due to different assumptions on fish swimming energetics. We conclude that fish are able to adjust both swimming speed and timing of swimming activity during...

  6. Swimming behavior and prey retention of the polychaete larvae Polydora ciliata (Johnston)

    DEFF Research Database (Denmark)

    Hansen, B.W.; Jakobsen, Hans Henrik; Andersen, Anders Peter

    2010-01-01

    in specific feeding rates and the observed increase in the difference between upward and downward swimming speeds with larval size. We estimated a critical larval length above which the buoyancy-corrected weight of the larva exceeds the propulsion force generated by the ciliary swimming apparatus and thus......The behavior of the ubiquitous estuarine planktotrophic spionid polychaete larvae Polydora ciliata was studied. We describe ontogenetic changes in morphology, swimming speed and feeding rates and have developed a simple swimming model using low Reynolds number hydrodynamics. In the model we assumed...... that the ciliary swimming apparatus is primarily composed of the prototroch and secondarily by the telotroch. The model predicted swimming speeds and feeding rates that corresponded well with the measured speeds and rates. Applying empirical data to the model, we were able to explain the profound decrease...

  7. Critical force during tethered swimming for the evaluation of aerobic capacity and prediction of performances in freestyle swimming

    Directory of Open Access Journals (Sweden)

    Marcelo Papoti

    2010-01-01

    Full Text Available The present study investigated the relationship of critical force (Fcrit with lactate threshold (LLNA and the intensity corresponding to VO2max (iVO2max in tethered swimming (TS, and their correlation with maximal performance in 400-m (V400 and 30-min (VT30 freestyle swimming (FS. Seven swimmers were submitted to a TS incremental test for the determination of LLNA and iVO2max. For the determination of Fcrit, the swimmers performed four exercises to exhaustion at intensities (F corresponding to 87%, 104%, 118% and 134% of iVO2max for the calculation of time limits (Tlim. Fcrit corresponded to the linear coefficient of the ratio between F and 1/tlim. The maximal performance in FS corresponded to the mean velocity obtained during maximal exercise of 400-m and 30-min crawl swimming. Fcrit (51.97 ± 4.02 N was significantly lower than iVO2max (60.21 ± 8.73 N but not than LLNA (45.89 ± 8.73. Fcrit was significantly correlated with iVO2max (0.97, LLNA (0.88, V400 (0.85, and VT30 (0.86. These data suggest that Fcrit can be used for the determination of aerobic capacity, prescription of a TS training program, and prediction of performance in FS.

  8. Hydrocarbon pollutants shape bacterial community assembly of harbor sediments

    KAUST Repository

    Barbato, Marta

    2016-02-02

    Petroleum pollution results in co-contamination by different classes of molecules, entailing the occurrence of marine sediments difficult to remediate, as in the case of the Ancona harbor (Mediterranean Sea, Italy). Autochthonous bioaugmentation (ABA), by exploiting the indigenous microbes of the environment to be treated, could represent a successful bioremediation strategy. In this perspective we aimed to i) identify the main drivers of the bacterial communities\\' richness in the sediments, ii) establish enrichment cultures with different hydrocarbon pollutants evaluating their effects on the bacterial communities\\' composition, and iii) obtain a collection of hydrocarbon degrading bacteria potentially exploitable in ABA. The correlation between the selection of different specialized bacterial populations and the type of pollutants was demonstrated by culture-independent analyses, and by establishing a collection of bacteria with different hydrocarbon degradation traits. Our observations indicate that pollution dictates the diversity of sediment bacterial communities and shapes the ABA potential in harbor sediments.

  9. Buffalo Harbor Study. Preliminary Feasibility Report. Volume I. Main Report.

    Science.gov (United States)

    1983-04-01

    to usually narrow strips of riparian vegetation, which is composed of various trees and shrubs of the Salix genus (willow), sumac, aspen, boxelder...reptiles were found. Species included, leopard frogs, snapping turtles, painted turtle, and garter snakes (SUNY Brockport: 1982). (7) Endangered Species...vessel traffic on the Buffalo River causes interrupted truck service. Firms have also cited snow removal as a problem. The harbor area road service

  10. Army Engineer Divers: First In Port-Au-Prince Harbor

    Science.gov (United States)

    2010-12-01

    to the pile once the concrete was poured. This step was com- pleted in a few minutes for each pile. Last, a prefabricated wooden form was emplaced...September-December 201010 Engineer This prefabricated wooden form was emplaced around a rebar cage at the top of damaged piles to hold concrete until it...the mainland into the harbor. Waste from tugboats and sewage from the mainland compounded ecological hazards. The only alternative for the Army and

  11. Environmental Assessment for Boston Harbor Maintenance Dredging, Boston, Massachusetts.

    Science.gov (United States)

    1981-12-01

    Harbor was developed by Jerome et al (1966), Chesmore et al (1971) and Iwanowicz et al. (1973). The studies on the Lower Mystic River were concentrated in... Iwanowicz et al. (1973) and this data should be referred to for detailed information. Waters overlying the shellfish beds are contaminated by wastes...DMRP Technical Report DS-78-5, Environmental Laboratory, U.S. Army Engineer Waterways Experiment Station, Vicksburg, Mississippi. Iwanowicz , H. R., R D

  12. An Evaluation of the Acquisition Streamlining Methods at the Fleet and Industrial Supply Center Pearl Harbor Hawaii

    National Research Council Canada - National Science Library

    Henry, Mark

    1999-01-01

    ...) Pearl Harbor's implementation of acquisition streamlining initiatives and recommends viable methods of streamlining the acquisition process at FISC Pearl Harbor and other Naval Supply Systems Command...

  13. The key kinematic determinants of undulatory underwater swimming at maximal velocity.

    Science.gov (United States)

    Connaboy, Chris; Naemi, Roozbeh; Brown, Susan; Psycharakis, Stelios; McCabe, Carla; Coleman, Simon; Sanders, Ross

    2016-01-01

    The optimisation of undulatory underwater swimming is highly important in competitive swimming performance. Nineteen kinematic variables were identified from previous research undertaken to assess undulatory underwater swimming performance. The purpose of the present study was to determine which kinematic variables were key to the production of maximal undulatory underwater swimming velocity. Kinematic data at maximal undulatory underwater swimming velocity were collected from 17 skilled swimmers. A series of separate backward-elimination analysis of covariance models was produced with cycle frequency and cycle length as dependent variables (DVs) and participant as a fixed factor, as including cycle frequency and cycle length would explain 100% of the maximal swimming velocity variance. The covariates identified in the cycle-frequency and cycle-length models were used to form the saturated model for maximal swimming velocity. The final parsimonious model identified three covariates (maximal knee joint angular velocity, maximal ankle angular velocity and knee range of movement) as determinants of the variance in maximal swimming velocity (adjusted-r2 = 0.929). However, when participant was removed as a fixed factor there was a large reduction in explained variance (adjusted r2 = 0.397) and only maximal knee joint angular velocity continued to contribute significantly, highlighting its importance to the production of maximal swimming velocity. The reduction in explained variance suggests an emphasis on inter-individual differences in undulatory underwater swimming technique and/or anthropometry. Future research should examine the efficacy of other anthropometric, kinematic and coordination variables to better understand the production of maximal swimming velocity and consider the importance of individual undulatory underwater swimming techniques when interpreting the data.

  14. Hygiene trap in swimming pools? Planning decisions with consequences; Hygienefalle Wasseraufbereitung in Schwimmbaedern. Planungsentscheidungen mit Folgen

    Energy Technology Data Exchange (ETDEWEB)

    Schellhorn, Martin [SHK-Presseagentur Kommunikations-Management Schellhorn GmbH, Haltern am See (Germany)

    2008-03-15

    Planning decisions often can be influenced by a domino effect. A causality pulls the other causality up until clear problems for example in a technical operational sequence are developed. A typical example for this is a water treatment plant in swimming pools. Finally, here it is decided how well the bather feels, how much bathers use the swimming pool and how large the economic success is. Just in the water purification and filtering of swimming pools the market shows a strongly differentiated picture.

  15. Towards an ethics safe harbor for global biomedical research

    Science.gov (United States)

    Dove, Edward S.; Knoppers, Bartha M.; Zawati, Ma'n H.

    2014-01-01

    Although increasingly global, data-driven genomics and other ‘omics’-focused research hold great promise for health discoveries, current research ethics review systems around the world challenge potential improvements in human health from such research. To overcome this challenge, we propose a ‘Safe Harbor Framework for International Ethics Equivalency’ that facilitates the harmonization of ethics review of specific types of data-driven international research projects while respecting globally transposable research ethics norms and principles. The Safe Harbor would consist in part of an agency supporting an International Federation for Ethics Review (IFER), formed by a voluntary compact among countries, granting agencies, philanthropies, institutions, and healthcare, patient advocacy, and research organizations. IFER would be both a central ethics review body, and also a forum for review and follow-up of policies concerning ethics norms for international research projects. It would be built on five principle elements: (1) registration, (2) compliance review, (3) recognition, (4) monitoring and enforcement, and (5) public participation. The Safe Harbor would create many benefits for researchers, countries, and the general public, and may eventually have application beyond (gen)omics to other areas of biomedical research that increasingly engage in secondary use of data and present only negligible risks. PMID:27774154

  16. Pearl Harbor: lessons for the dam safety community

    Energy Technology Data Exchange (ETDEWEB)

    Martin, T.E. [AMEC Earth and Environmental Ltd., Burnaby, BC (Canada)

    2001-10-01

    Every good dam safety program must be based on surveillance and emergency response planning. The same principles apply to the gathering of information for military intelligence and the planning of defence tactics. Lessons learned from failure have spurred the advancement of dam engineering. Dam safety experts can benefit from the inadequacies encountered by the military community, with the most famous occurring on December 7, 1941 in Pearl Harbor. Both intelligence gathering and contingency response planning failed miserably. The data was not properly disseminated, interpreted, analysed. The proper response to the situation was not initiated. Human error and failure to communicate are the two main reasons that explain the debacle. The inquiries into the tragedy at Pearl Harbor provided valuable lessons, related to individual and organizational failures, which the authors shared in this presentation. The relevance to dam safety was made. All Federal Bureau of Investigation (FBI) agents must read the lessons drawn from Pearl Harbor, as they have responsibility for dam safety. 4 refs.

  17. Coronary ligation reduces maximum sustained swimming speed in Chinook salmon, Oncorhynchus tshawytscha

    DEFF Research Database (Denmark)

    Farrell, A P; Steffensen, J F

    1987-01-01

    The maximum aerobic swimming speed of Chinook salmon (Oncorhynchus tshawytscha) was measured before and after ligation of the coronary artery. Coronary artery ligation prevented blood flow to the compact layer of the ventricular myocardium, which represents 30% of the ventricular mass, and produced...... a statistically significant 35.5% reduction in maximum swimming speed. We conclude that the coronary circulation is important for maximum aerobic swimming and implicit in this conclusion is that maximum cardiac performance is probably necessary for maximum aerobic swimming performance....

  18. On burst-and-coast swimming performance in fish-like locomotion

    International Nuclear Information System (INIS)

    Chung, M-H

    2009-01-01

    Burst-and-coast swimming performance in fish-like locomotion is studied via two-dimensional numerical simulation. The numerical method used is the collocated finite-volume adaptive Cartesian cut-cell method developed previously. The NACA00xx airfoil shape is used as an equilibrium fish-body form. Swimming in a burst-and-coast style is computed assuming that the burst phase is composed of a single tail-beat. Swimming efficiency is evaluated in terms of the mass-specific cost of transport instead of the Froude efficiency. The effects of the Reynolds number (based on the body length and burst time), duty cycle and fineness ratio (the body length over the largest thickness) on swimming performance (momentum capacity and the mass-specific cost of transport) are studied quantitatively. The results lead to a conclusion consistent with previous findings that a larval fish seldom swims in a burst-and-coast style. Given mass and swimming speed, a fish needs the least cost if it swims in a burst-and-coast style with a fineness ratio of 8.33. This energetically optimal fineness ratio is larger than that derived from the simple hydromechanical model proposed in literature. The calculated amount of energy saving in burst-and-coast swimming is comparable with the real-fish estimation in the literature. Finally, the predicted wake-vortex structures of both continuous and burst-and-coast swimming are biologically relevant.

  19. The Effect of Swimming on the Lung Functions in Healthy Young Male Population of Amritsar

    Directory of Open Access Journals (Sweden)

    Mahajan Shashi

    2013-12-01

    Full Text Available Aim of this research is to study the effects of swimming on the lung functions in adult male population of Amritsar. Many exercise physiologists study the effect of exercise on pathology, and the mechanisms by which exercise can reduce or reverse disease progression. The present study was undertaken to study the effects swimming on the lung functions. Pulmonary function tests (PFTs of swimming trainees were compared with those of controls. We evaluated PFTs in 50 healthy subjects who participated in a 3 months of swimming plan. Pulmonary function tests were recorded before the commencement of swimming and at the end of swimming and compared the values so obtained with 50 healthy non- swimmers who were chosen as controls. The controls were the physiotherapy students from Khalsa College Amritsar. Both were in the age group of 18- 20 years. The PFTs were carried out with a computerized spirometer “Med-Spiror”. The various data was collected, compiled, statistically analysed and valid conclusions were drawn. Higher lung volumes and flow rates were achieved in swimming trainees after their training period, as compared to their own values obtained before their training period and to those of controls. Regular exercise enhances physical capabilities and physiological responses of the human body and also in the lungs. The cause of improved of various respiratory functions and flow rates after  swimming duration was better mechanical factors and lower airway resistance influenced during the training period. Key words: Pulmonary; Expiration; Swimming; Pulmonary Function Test

  20. Removal of spike frequency adaptation via neuromodulation intrinsic to the Tritonia escape swim central pattern generator.

    Science.gov (United States)

    Katz, P S; Frost, W N

    1997-10-15

    For the mollusc Tritonia diomedea to generate its escape swim motor pattern, interneuron C2, a crucial member of the central pattern generator (CPG) for this rhythmic behavior, must fire repetitive bursts of action potentials. Yet, before swimming, repeated depolarizing current pulses injected into C2 at periods similar those in the swim motor program are incapable of mimicking the firing rate attained by C2 on each cycle of a swim motor program. This resting level of C2 inexcitability is attributable to its own inherent spike frequency adaptation (SFA). Clearly, this property must be altered for the swim behavior to occur. The pathway for initiation of the swimming behavior involves activation of the serotonergic dorsal swim interneurons (DSIs), which are also intrinsic members of the swim CPG. Physiologically appropriate DSI stimulation transiently decreases C2 SFA, allowing C2 to fire at higher rates even when repeatedly depolarized at short intervals. The increased C2 excitability caused by DSI stimulation is mimicked and occluded by serotonin application. Furthermore, the change in excitability is not caused by the depolarization associated with DSI stimulation or serotonin application but is correlated with a decrease in C2 spike afterhyperpolarization. This suggests that the DSIs use serotonin to evoke a neuromodulatory action on a conductance in C2 that regulates its firing rate. This modulatory action of one CPG neuron on another is likely to play a role in configuring the swim circuit into its rhythmic pattern-generating mode and maintaining it in that state.

  1. Fluid-mediated stability and speed-increase for heaving hydrofoils swimming side-by-side

    Science.gov (United States)

    Newbolt, Joel; Zhang, Jun; Ristroph, Leif

    2017-11-01

    As an example of collective motion in active swimmers we study the fluid-mediated interaction between two heaving hydrofoils that swim with a fixed transverse separation (between the heaving mid-heights) but are free to independently choose their forward swimming speeds and positions. Experiments reveal that out-of-phase foils are attracted to a side-by-side configuration which also increases the swimming speed of the pair (up to 59% faster for our parameters), while in-phase foils are repelled from this configuration. Because this type of swimming is qualitatively similar to that of fish and birds this interaction could be important to schooling and flocking.

  2. Estimating fish swimming metrics and metabolic rates with accelerometers: the influence of sampling frequency.

    Science.gov (United States)

    Brownscombe, J W; Lennox, R J; Danylchuk, A J; Cooke, S J

    2018-06-21

    Accelerometry is growing in popularity for remotely measuring fish swimming metrics, but appropriate sampling frequencies for accurately measuring these metrics are not well studied. This research examined the influence of sampling frequency (1-25 Hz) with tri-axial accelerometer biologgers on estimates of overall dynamic body acceleration (ODBA), tail-beat frequency, swimming speed and metabolic rate of bonefish Albula vulpes in a swim-tunnel respirometer and free-swimming in a wetland mesocosm. In the swim tunnel, sampling frequencies of ≥ 5 Hz were sufficient to establish strong relationships between ODBA, swimming speed and metabolic rate. However, in free-swimming bonefish, estimates of metabolic rate were more variable below 10 Hz. Sampling frequencies should be at least twice the maximum tail-beat frequency to estimate this metric effectively, which is generally higher than those required to estimate ODBA, swimming speed and metabolic rate. While optimal sampling frequency probably varies among species due to tail-beat frequency and swimming style, this study provides a reference point with a medium body-sized sub-carangiform teleost fish, enabling researchers to measure these metrics effectively and maximize study duration. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  3. On burst-and-coast swimming performance in fish-like locomotion.

    Science.gov (United States)

    Chung, M-H

    2009-09-01

    Burst-and-coast swimming performance in fish-like locomotion is studied via two-dimensional numerical simulation. The numerical method used is the collocated finite-volume adaptive Cartesian cut-cell method developed previously. The NACA00xx airfoil shape is used as an equilibrium fish-body form. Swimming in a burst-and-coast style is computed assuming that the burst phase is composed of a single tail-beat. Swimming efficiency is evaluated in terms of the mass-specific cost of transport instead of the Froude efficiency. The effects of the Reynolds number (based on the body length and burst time), duty cycle and fineness ratio (the body length over the largest thickness) on swimming performance (momentum capacity and the mass-specific cost of transport) are studied quantitatively. The results lead to a conclusion consistent with previous findings that a larval fish seldom swims in a burst-and-coast style. Given mass and swimming speed, a fish needs the least cost if it swims in a burst-and-coast style with a fineness ratio of 8.33. This energetically optimal fineness ratio is larger than that derived from the simple hydromechanical model proposed in literature. The calculated amount of energy saving in burst-and-coast swimming is comparable with the real-fish estimation in the literature. Finally, the predicted wake-vortex structures of both continuous and burst-and-coast swimming are biologically relevant.

  4. Biochemical and Hematological Changes Following the 120-Km Open-Water Marathon Swim

    Directory of Open Access Journals (Sweden)

    Wojciech Drygas, Ewa Rębowska, Ewa Stępień, Jacek Golański, Magdalena Kwaśniewska

    2014-09-01

    Full Text Available Data on physiological effects and potential risks of a ultraendurance swimming are scarce. This report presents the unique case of a 61-year old athlete who completed a non-stop open-water 120-km ultramarathon swim on the Warta River, Poland. Pre-swimming examinations revealed favorable conditions (blood pressure, 110/70 mmHg; rest heart rate, 54 beats/minute, ejection fraction, 60%, 20.2 metabolic equivalents in a maximal exercise test. The swimming time and distance covered were 27 h 33 min and 120 km, respectively. Blood samples for hematological and biochemical parameters were collected 30 min, 4 hrs, 10 hrs and 8 days after the swim. The body temperature of the swimmer was 36.7°C before and 35.1°C after the swim. The hematological parameters remained within the reference range in the postexercise period except for leucocytes (17.5 and 10.6 x G/l noted 30 minutes and 4 hours after the swim, respectively. Serum urea, aspartate aminotransferase and C-reactive protein increased above the reference range reaching 11.3 mmol/l, 1054 nmol/l/s and 25.9 mg/l, respectively. Symptomatic hyponatremia was not observed. Although the results demonstrate that an experienced athlete is able to complete an ultra-marathon swim without negative health consequences, further studies addressing the potential risks of marathon swimming are required.

  5. Processes influencing the transport and fate of contaminated sediments in the coastal ocean: Boston Harbor and Massachusetts Bay

    Science.gov (United States)

    Alexander, P. Soupy; Baldwin, Sandra M.; Blackwood, Dann S.; Borden, Jonathan; Casso, Michael A.; Crusius, John; Goudreau, Joanne; Kalnejais, Linda H.; Lamothe, Paul J.; Martin, William R.; Martini, Marinna A.; Rendigs, Richard R.; Sayles, Frederick L.; Signell, Richard P.; Valentine, Page C.; Warner, John C.; Bothner, Michael H.; Butman, Bradford

    2007-01-01

    coastal systems in general. Scientific data from this region can also be used to inform decisions about important economic, environmental, and political issues. From the economic viewpoint, the annual value of tourism and shipping in Massachusetts and Cape Cod Bays is about $1.5 billion and $1.9 billion, respectively. Commercial and recreational fishing generates about $240 million per year in the same region (U.S. Environmental Protection Agency, 2005b). The environmental issue is the 300-year history of waste discharge from the Boston metropolitan area into the harbor. This history is punctuated by cycles of environmental degradation, public outcry, and improvements in the sewage treatment system. With each improvement, however, the continuous growth of population in greater Boston (fig. 1.2) and the resulting increase in the volume of waste exceeded the capacity of the treatment system, thereby setting the stage for a new contamination crisis. By the 1980s, the levels of contaminants in sediments of Boston Harbor were among the highest in the nation (National Oceanic and Atmospheric Administration, 1987). Fish were diseased, shellfish beds were closed, and swimming beaches were unsafe after heavy rains; in general, water quality and aesthetics were below acceptable standards. Legal and political issues have always been part of Boston Harbor’s history. The environmental conditions in the 1980s were highlighted in a 1983 legal suit brought by the city of Quincy against the Metropolitan District Commission (MDC, the state agency responsible for sewage treatment) and heads of three state agencies for discharging untreated or poorly treated sewage into the harbor (Dolin, 2004). The suit never went to trial, but through the actions of a Massachusetts Superior Court, the issue of Boston Harbor contamination remained on the political and public agenda. The judge called the harbor “unsafe, unsanitary, indecent, in violation of the law (Clean Water Act), and a danger to the

  6. Effects of Harbor Modification on Crescent City, California's Tsunami Vulnerability

    Science.gov (United States)

    Dengler, Lori; Uslu, Burak

    2011-06-01

    More damaging tsunamis have impacted Crescent City, California in historic times than any other location on the West Coast of the USA. Crescent City's harbor has undergone significant modification since the early 20th century, including construction of several breakwaters, dredging, and a 200 × 300 m2 small boat basin. In 2006, a M w 8.3 earthquake in the Kuril Islands generated a moderate Pacific-wide tsunami. Crescent City recorded the highest amplitudes of any tide gauge in the Pacific and was the only location to experience structural damage. Strong currents damaged docks and boats within the small boat basin, causing more than US 20 million in damage and replacement costs. We examine how modifications to Crescent City's harbor may have affected its vulnerability to moderate tsunamis such as the 2006 event. A bathymetric grid of the basin was constructed based on US Army Corps of Engineers soundings in 1964 and 1965 before the construction of the small boat basin. The method of splitting tsunamis was used to estimate tsunami water heights and current velocities at several locations in the harbor using both the 1964-1965 grid and the 2006 bathymetric grid for the 2006 Kuril event and a similar-sized source along the Sanriku coast of Japan. Model velocity outputs are compared for the two different bathymetries at the tide gauge location and at six additional computational sites in the harbor. The largest difference between the two grids is at the small boat basin entrance, where the 2006 bathymetry produces currents over three times the strength of the currents produced by the 1965 bathymetry. Peak currents from a Sanriku event are comparable to those produced by the 2006 event, and within the boat basin may have been higher. The modifications of the harbor, and in particular the addition of the small boat basin, appear to have contributed to the high current velocities and resulting damage in 2006 and help to explain why the 1933 M w 8.4-8.7 Sanriku tsunami

  7. Grays Harbor and Chehalis River Improvements to Navigation Environmental Studies. Wildlife Studies at Proposed Disposal Sites in Grays Harbor, Washington,

    Science.gov (United States)

    1982-01-01

    sltand. T 𔃼~P i’ W 210 three times VtwCerI November IOC’C -nd ~co l.Etls ~ ec!,!zervc-o betxwe H -gF 12 Th -ind hl rway u- 7Plie Sicuobh. E. Cumin -s 1... stress imposed by dredge dsosal ;ictivities on these species. It is difficult to rredict the effects of establishing a salt marsh in Grays Harbor on

  8. The swimming program effects on the gross motor function, mental adjustment to the aquatic environment, and swimming skills in children with cerebral palsy: A pilot study

    Directory of Open Access Journals (Sweden)

    Jorgić Bojan

    2012-01-01

    Full Text Available The aim of this research was to determine the swimming program effects on the gross motor function, mental adjustment to the aquatic environment and the ability to move in the water and swim in children with cerebral palsy. The sample consisted of seven children (4 boys and 3 girls with spastic cerebral palsy and an average age of 9y 5mo ± 1y 3 mo. The swimming program lasted 6 weeks, with two swimming sessions per week. Each session lasted 45 minutes. The swimming program included the application of the Halliwick Method and swimming exercises which are used in a healthy population. The GMFM test was used for the assessment of gross motor functions. The WOTA2 test was applied to assess mental adjustment and swimming skills. The Wilcoxon matched pairs test was used to determine the statistically significant differences between the initial and final measuring. The results have indicated that there was statistically significant differences in the E dimension (p=0.04 and the total score T (p=0.03 of the GMFM test, then for mental adjustment to the aquatic environment WMA (p=0.02, ability to move in water andswimming skills WSW (p=0.03 and the overall result WTO (p=0.02 of the WOTA2 test. The applied swimming program had a statistically significant effect on the improvement in walking, running and jumping as well as the overall gross motor functions of children with cerebral palsy. The applied program also contributed to a statistically significant influence on the increase in mental adjustment to the aquatic environment and the ability to move in water and swim.

  9. High-intensity high-volume swimming induces more robust signaling through PGC-1α and AMPK activation than sprint interval swimming in m. triceps brachii

    DEFF Research Database (Denmark)

    Casuso, Rafael A; Plaza-Díaz, Julio; Ruiz-Ojeda, Francisco J

    2017-01-01

    We aimed to test whether high-intensity high-volume training (HIHVT) swimming would induce more robust signaling than sprint interval training (SIT) swimming within the m. triceps brachii due to lower metabolic and oxidation. Nine well-trained swimmers performed the two training procedures...... on separate randomized days. Muscle biopsies from m. triceps brachii and blood samples were collected at three different time points: a) before the intervention (pre), b) immediately after the swimming procedures (post) and c) after 3 h of rest (3 h). Hydroperoxides, creatine kinase (CK), and lactate...

  10. EFFECTIVENESS OF DOUBLE WASH SWIM-UP VERSUS DOUBLE DENSITY GRADIENT SWIM-UP TECHNIQUE OF SPERM PREPARATION IN IN VITRO FERTILISATION

    Directory of Open Access Journals (Sweden)

    Srinivas Sangisapu

    2017-10-01

    Full Text Available BACKGROUND Recovery of optimum number of good quality of spermatozoa is an important component of In Vitro Fertilisation (IVF. This is achieved by sperm preparation methods involving separation and recovery of capacitated sperms. Double Wash Swim-up (DWSU and Double Density Gradient Swim-up (DDGSU are two most accepted methods. Cochrane systematic review (2007 finds no clear benefit of one method over the other in Intrauterine Insemination (IUI. Systematic review on effectiveness of these preparations in IVF is lacking. Effectiveness is generally assessed in terms recovery rates of the sperms. Capability of successful fertilisation of good quality oocytes should ideally be the functional endpoint for evaluating effectiveness of sperm preparation methods. The aim of the study is to1. Compare the successful fertilisation rates of oocytes inseminated by semen preparation of Double Wash Swim-up (DWSU vis-a-vis by Double Density Gradient Swim-up (DDGSU method. 2. Evaluate the effectiveness of fertilisation of oocytes by Double Wash Swim-up method (DWSU vis-a-vis Double Density Gradient Swim-up (DDGSU method. MATERIALS AND METHODS A retrospective cohort study was conducted on infertile couples undergoing IVF from June 2014 to June 2017 at an ART Centre of a tertiary care hospital. The male partners were normozoospermic and female partners were normoresponsive to controlled ovarian stimulation and oocyte retrieval. RESULTS 70 male partners were subjected to double wash swim-up and 64 underwent double density gradient swim-up preparation. 1296 good quality oocytes were retrieved in their respective female partners. 452 (61% out of 742 oocytes were successfully fertilised after insemination by semen prepared by DWSU method. 378 (68% oocytes out of 554 were fertilised by insemination with semen prepared by DDGSU method. There seems to be strong association (RR=1.12 of fertilisation success with oocytes exposed to semen prepared by Double Density Gradient

  11. Resilience in shock and swim stress models of depression

    Directory of Open Access Journals (Sweden)

    Robert Charles Drugan

    2013-02-01

    Full Text Available Experimental models of depression often entail exposing a rodent to a stressor and subsequently characterizing changes in learning and anhedonia, which may reflect symptoms of human depression. Importantly, not all people and not all laboratory rats exposed to stressors develop depressed behavior; these resilient individuals are the focus of our review. Herein we describe research from the learned helplessness and intermittent swim stress models of depression in which rats that were allowed to cope with the stressor appear to be behaviorally and neurochemically similar to rats that were not allowed to cope yet appeared resilient in behavioral tests. For example, rats exposed to inescapable tailshock, but do not develop learned helplessness, exhibit altered sensitivity to the behavioral effects of GABAA receptor antagonists and reduced in vitro benzodiazepine receptor ligand binding. This pattern suggested that resilience might involve activation of an endogenous benzodiazepine-like compound, possibly an allostatic modulator of the GABAA receptor like allopregnanolone. From the intermittent swim stress model, we have observed in resilient rats protection from stressor-induced glucocorticoid increases and immune activation. In order to identify the neural mediators of these correlates of resilience, non-invasive measures are needed to predict the resilient or vulnerable phenotype prior to analysis of neural endpoints. To this end, we found that ultrasonic vocalizations (USVs appear to predict the resilient phenotype in the intermittent swim stress paradigm. We propose that combining non-invasive predictive measures, such as USVs with biological endpoint measures, will facilitate future research into the neural correlates of resilience.

  12. Antidepressant effect of Melissa officinalis in the forced swimming test

    Directory of Open Access Journals (Sweden)

    M Emamghoreishi

    2009-03-01

    Full Text Available ABSTRACT Background: In Iranian and other traditional medicines, an antidepressant effect has been indicated for Melissa officinalis (Lamiaceae. However, studies showing its antidepressant effect is lacking. Therefore, the present study was undertaken to examine whether the aqueous extract and essential oil from leaves of Melissa officinalis have an antidepressant-like activity in mice.  Materials and Methods: The effect of subchronic administration of different doses of the aqueous extract (25, 75, 150, 300 mg/kg or water; n=9-10 and the essential oil (10, 25, 75, 150, 300 mg/kg or almond oil; n=9-10 on immobility, climbing, and swimming behaviors were evaluated in the forced swimming test. Fluoxetine (20mg/kg and imipramine (15 mg/kg were used as reference drugs. Additionally, the effect of both plant preparations on spontaneous activity was examined. Results: All doses of the aqueous extract, used in this study, produced a significant reduction in immobility along with an increase in climbing behavior which is similar to those which have been observed with imipramine. Essential oil caused a dose-dependent reduction in immobility and an increase in climbing at all studied doses, compared to control group. Only the highest dose (300mg/kg of essential oil showed a significant increase in swimming behavior. The aqueous extract, but not the essential oil, decreased spontaneous activity in a dose dependent manner. Conclusion: The results of this study suggests that the Melissa officinalis possess an antidepressant-like activity similar to imipramine which may have a potential clinical value for treatment of depression.

  13. Lip and tooth injuries at public swimming pools in Austria.

    Science.gov (United States)

    Lechner, Katharina; Connert, Thomas; Kühl, Sebastian; Filippi, Andreas

    2017-06-01

    There is an increased risk of orofacial injuries in swimming pool facilities. Nevertheless, only a few studies have addressed this issue. The aim of this study was to identify the frequency of lip and tooth injuries at public swimming pools in Austria. A further aim was to examine which gender and age groups were affected, where and why these injuries occurred, and whether pool attendants had sufficient knowledge of dental first-aid measures. A total of 764 pool attendants in Austria were contacted by telephone and 689 participated in the study (90.2%). The attendants were interviewed retrospectively about accident occurrences in 2014 by a standardized questionnaire. Responses to the provision of first aid and choice of storage medium for avulsed teeth were subsequently evaluated. The frequency of lip injuries was 19.0%, and tooth injuries were 11.3%. Male bathers (P < .05) and children under 12 years (P < .001) most frequently suffered injuries. The waterslide was the most common accident site. The most common cause of lip injuries was slipping on wet surfaces (39.0%), and for tooth injuries it was collisions with other persons or objects (each 28.1%). The pool attendants' responses were predominantly good or sufficient on first aid, with the exception of what storage medium to choose. Tooth rescue boxes were available in only 8.6% of all pool facilities. Orofacial injuries are a frequently occurring problem in swimming pool facilities. The pool attendants' knowledge on first-aid care of tooth injuries could still be improved. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Applying physiological principles and assessment techniques to swimming the English Channel. A case study.

    Science.gov (United States)

    Acevedo, E O; Meyers, M C; Hayman, M; Haskin, J

    1997-03-01

    This study presents the use of physiological principles and assessment techniques in addressing four objectives that can enhance a swimmer's likelihood of successfully swimming the English Channel. The four objective were: (1) to prescribe training intensities and determine ideal swimming pace; (2) to determine the amount of insulation needed, relative to heat produced, to diminish the likelihood of the swimmer suffering from hypothermia; (3) to calculate the caloric expenditure for the swim and the necessary glucose replacement required to prevent glycogen depletion; and (4) to determine the rate of acclimatization to cold water (15.56 C/60 F). The subject participated in several pool swimming data collection sessions including a tethered swim incremental protocol to determine peak oxygen consumption and onset of lactate accumulation and several steady state swims to determine ideal swimming pace at 4.0 mM/L of lactate. Additionally, these swims provided information on oxygen consumption, which in combination with ultrasound assessment of subcutaneous fat was used to assess heat production and insulation capabilities. Finally, the subject participated in 18 cold water immersions to document acclimatization rate. The data demonstrated the high fitness level of this subject and indicated that at a stroke rate of 63 stokes/min, HR was 130 heats/min and lactate was 4 mM/L. At this swimming pace the swimmer would need to consume 470 kcal of glucose/hr. In addition, the energy produced at this swim pace was 13.25 kcal/min while the energy lost at the present subcutaneous fat quantity was 13.40 kcal/min, requiring a fat weight gain of 6,363.03 g (13.88 lbs) to resist heat loss. Finally, the data from the cold water immersions suggested that acclimatization occurred following two weeks of immersions. There results were provided to the swimmer and utilized in making decisions in preparation for the swim.

  15. Dioxin inhibition of swim bladder development in zebrafish: is it secondary to heart failure?

    Science.gov (United States)

    Yue, Monica S; Peterson, Richard E; Heideman, Warren

    2015-05-01

    The swim bladder is a gas-filled organ that is used for regulating buoyancy and is essential for survival in most teleost species. In zebrafish, swim bladder development begins during embryogenesis and inflation occurs within 5 days post fertilization (dpf). Embryos exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) before 96 h post fertilization (hpf) developed swim bladders normally until the growth/elongation phase, at which point growth was arrested. It is known that TCDD exposure causes heart malformations that lead to heart failure in zebrafish larvae, and that blood circulation is a key factor in normal development of the swim bladder. The adverse effects of TCDD exposure on the heart occur during the same period of time that swim bladder development and growth occurs. Based on this coincident timing, and the dependence of swim bladder development on proper circulatory development, we hypothesized that the adverse effects of TCDD on swim bladder development were secondary to heart failure. We compared swim bladder development in TCDD-exposed embryos to: (1) silent heart morphants, which lack cardiac contractility, and (2) transiently transgenic cmlc2:caAHR-2AtRFP embryos, which mimic TCDD-induced heart failure via heart-specific, constitutive activation of AHR signaling. Both of these treatment groups, which were not exposed to TCDD, developed hypoplastic swim bladders of comparable size and morphology to those found in TCDD-exposed embryos. Furthermore, in all treatment groups swim bladder development was arrested during the growth/elongation phase. Together, these findings support a potential role for heart failure in the inhibition of swim bladder development caused by TCDD. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. SWIMS: a small-angle multiple scattering computer code

    International Nuclear Information System (INIS)

    Sayer, R.O.

    1976-07-01

    SWIMS (Sigmund and WInterbon Multiple Scattering) is a computer code for calculation of the angular dispersion of ion beams that undergo small-angle, incoherent multiple scattering by gaseous or solid media. The code uses the tabulated angular distributions of Sigmund and Winterbon for a Thomas-Fermi screened Coulomb potential. The fraction of the incident beam scattered into a cone defined by the polar angle α is computed as a function of α for reduced thicknesses over the range 0.01 less than or equal to tau less than or equal to 10.0. 1 figure, 2 tables

  17. Stringy and Membranic Theory of Swimming of Micro-organisms

    OpenAIRE

    Kawamura, Masako; Nojiri, Shin'ichi; Sugamoto, Akio

    1996-01-01

    When the swimming of micro-organisms is viewed from the string and membrane theories coupled to the velocity field of the fluid, a number of interesting results are derived; 1) importance of the area (or volume) preserving algebra, 2) usefulness of the $N$-point Reggeon (membranic) amplitudes, and of the gas to liquid transition in case of the red tide issues, 3) close relation between the red tide issue and the generation of Einstein gravity, and 4) possible understanding of the three differ...

  18. Some equipment for graphite research in swimming pool reactors

    International Nuclear Information System (INIS)

    Seguin, M.; Arragon, Ph.; Dupont, G.; Gentil, J.; Tanis, G.

    1964-01-01

    The irradiation devices described are used for research concerning reactors of the natural uranium type, moderated by graphite and cooled by carbon dioxide. The devices are generally designed for use in swimming pool reactors. The following points have been particularly studied: - maximum use of the irradiation volume, - use of the simplest technological solutions, - standardization of certain constituent parts. This standardization calls for precision machining and careful assembling; these requirements are also true when a relatively low irradiation temperature is required and the nuclear heating is pronounced. Finally, the design of these devices is suitable for the irradiation of other fissile or non-fissile materials. (authors) [fr

  19. Predator localization by sensory hairs in free-swimming arthropods

    Science.gov (United States)

    Takagi, Daisuke; Hartline, Daniel K.

    2016-11-01

    Free-swimming arthropods such as copepods rely on minute deflections of cuticular hairs (or "setae") for local flow sensing that is needed to detect food and escape from predators. We present a simple hydrodynamic model to analyze how the location, speed, and size of an approaching distant predator can be inferred from local flow deformation alone. The model informs suitable strategies of escape from an imminent predatory attack. The sensory capabilities of aquatic arthropods could inspire the design of flow sensors in technological applications.

  20. Software for the Design of Swimming Pool Dehumidifiers Units

    Science.gov (United States)

    Rubina, Aleš; Blasinski, Petr; Tesař, Zdeněk

    2013-06-01

    The article deals with the description and solution of physical phenomena taking place during evaporation of water. The topicality of the theme is given a number of built indoor swimming pool and wellness centers at present. In addressing HVAC systems serving these areas, it is necessary to know the various design parameters in the interior including the water temperature as the pool temperature and humidity. Following is a description of the calculation module, air handling units, including optimizing the settings of the physical changes in order to ensure the lowest energy consumption for air treatment and required maintaining internal microclimate parameters.

  1. Analysis of SBO accident for a swimming pool reactor

    International Nuclear Information System (INIS)

    Wang Guimin; Li Weiwei; Li Ning; Guo Wenhui

    2015-01-01

    The RELAP5/MOD3.3 code was adopted to compute the SBO accident condition of a swimming pool reactor. The coolant flow reversal process was calculated, and the influence of parameters of the flow between the core leakage and components on the flow reversal in the SBO accident condition was analyzed. The calculated results show that in the situation the reactor loses all forced flow, the residual heat of the reactor can be removed by the natural circulation flow, and the fuel subassembly will not be damaged. (authors)

  2. Investigating the Swimming of Microbial Pathogens Using Digital Holography.

    Science.gov (United States)

    Thornton, K L; Findlay, R C; Walrad, P B; Wilson, L G

    2016-01-01

    To understand much of the behaviour of microbial pathogens, it is necessary to image living cells, their interactions with each other and with host cells. Species such as Escherichia coli are difficult subjects to image: they are typically microscopic, colourless and transparent. Traditional cell visualisation techniques such as fluorescent tagging or phase-contrast microscopy give excellent information on cell behaviour in two dimensions, but no information about cells moving in three dimensions. We review the use of digital holographic microscopy for three-dimensional imaging at high speeds, and demonstrate its use for capturing the shape and swimming behaviour of three important model pathogens: E. coli, Plasmodium spp. and Leishmania spp.

  3. Flow Structures and Efficiency of Swimming Fish school: Numerical Study

    Science.gov (United States)

    Yatagai, Yuzuru; Hattori, Yuji

    2013-11-01

    The flow structure and energy-saving mechanism in fish school is numerically investigated by using the volume penalization method. We calculate the various patterns of configuration of fishes and investigate the relation between spatial arrangement and the performance of fish. It is found that the down-stream fish gains a hydrodynamic advantage from the upstream wake shed by the upstream fish. The most efficient configuration is that the downstream fish is placed in the wake. It reduces the drag force of the downstream fish in comparison with that in solo swimming.

  4. Energy savings in sea bass swimming in a school: measurements of tail beat frequency and oxygen consumption at different swimming speeds

    DEFF Research Database (Denmark)

    Herskin, J; Steffensen, JF

    1998-01-01

    Tail beat frequency of sea bass, Dicentrarchus labrax (L.) (23.5 ± 0·5 cm, LT), swimming at the front of a school was significantly higher than when swimming at the rear, for all water velocities tested from 14·8 to 32 cm s-1. The logarithm of oxygen consumption rate, and the tail beat frequency...... of solitary swimming sea bass (28·8 ± 0·4 cm, LT), were each correlated linearly with swimming speed, and also with one another. The tail beat frequency of individual fish was 9-14% lower when at the rear of a school than when at the front, corresponding to a 9-23% reduction in oxygen consumption rate....

  5. Intrinsic neuromodulation in the Tritonia swim CPG: serotonin mediates both neuromodulation and neurotransmission by the dorsal swim interneurons.

    Science.gov (United States)

    Katz, P S; Frost, W N

    1995-12-01

    1. Neuromodulation has previously been shown to be intrinsic to the central pattern generator (CPG) circuit that generates the escape swim of the nudibranch mollusk Tritonia diomedea; the dorsal swim interneurons (DSIs) make conventional monosynaptic connections and evoke neuromodulatory effects within the swim motor circuit. The conventional synaptic potentials evoked by a DSI onto cerebral neuron 2 (C2) and onto the dorsal flexion neurons (DFNs) consist of a fast excitatory postsynaptic potential (EPSP) followed by a prolonged slow EPSP. In their neuromodulatory role, the DSIs produce an enhancement of the monosynaptic connections made by C2 onto other CPG circuit interneurons and onto efferent flexion neurons. Previous work showed that the DSIs are immunoreactive for serotonin. Here we provide evidence that both the neurotransmission and the neuromodulation evoked by the DSIs are produced by serotonin, and that these effects may be pharmacologically separable. 2. Previously it was shown that bath-applied serotonin both mimics and occludes the modulation of the C2 synapses by the DSIs. Here we find that pressure-applied puffs of serotonin mimic both the fast and slow EPSPs evoked by a DSI onto a DFN, whereas high concentrations of bath-applied serotonin occlude both of these synaptic components. 3. Consistent with the hypothesis that serotonin mediates the actions of the DSIs, the serotonin reuptake inhibitor imipramine prolongs the duration of the fast DSI-DFN EPSP, increases the amplitude of the slow DSI-DFN EPSP, and increases both the amplitude and duration of the modulation of the C2-DFN synapse by the DSIs. 4. Two serotonergic antagonists were found that block the actions of the DSIs. Gramine blocks the fast DSI-DFN EPSP, and has far less of an effect on the slow EPSP and the modulation. Gramine also diminishes the depolarization evoked by pressure-applied serotonin, showing that it is a serotonin antagonist in this system. In contrast, methysergide greatly

  6. Evaluation and Treatment of Swimming Pool Avoidance Exhibited by an Adolescent Girl with Autism

    Science.gov (United States)

    Rapp, John T.; Vollmer, Timothy R.; Hovanetz, Alyson N.

    2005-01-01

    We evaluated and treated swimming pool avoidance that was exhibited by a 14-year-old girl diagnosed with autism. In part, treatment involved blocking for flopping (dropping to the ground) and elopement (running away from the pool) and access to food for movements toward a swimming pool. Treatment also involved reinforcement for exposure to various…

  7. 36 CFR 3.16 - May I swim or wade in park waters?

    Science.gov (United States)

    2010-07-01

    ... waters? 3.16 Section 3.16 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.16 May I swim or wade in park waters? Swimming or wading is allowed in waters, subject to closures or restrictions designated by the superintendent in accordance with...

  8. Relationship between the effect of dietary fat on swimming endurance and energy metabolism in aged mice.

    Science.gov (United States)

    Zhang, Guihua; Shirai, Nobuya; Suzuki, Hiramitsu

    2011-10-01

    The aim of this study was to investigate the effect of different dietary fats on alterations in endurance, energy metabolism, and plasma levels of interleukin-6 (IL-6) and minerals in mice. Male mice (aged 58 weeks) were fed diets containing 6% safflower oil, fish oil, or lard for 12 weeks. Swimming time to exhaustion, energy metabolism, and plasma IL-6 levels were subsequently determined. Mice fed safflower oil exhibited a marked increase in swimming time compared to the baseline level. Mice fed lard exhibited a significant decrease in swimming time, while mice on a fish oil diet exhibited a small decrease in swimming time. The final swimming time of mice fed safflower oil was significantly longer than that of animals fed lard. This improvement in endurance with dietary safflower oil was accompanied by decreased accumulation of lactate and less glycogen depletion during swimming. In the safflower oil group, muscle carnitine palmitoyltransferase activity increased significantly after swimming, while the plasma non-esterified fatty acid concentration decreased significantly. A trend to increased plasma IL-6 levels was observed in sedentary animals on a safflower oil diet compared to those on a lard diet. These results suggest that dietary safflower oil improves the swimming endurance of aged mice to a greater extent than lard, and that this effect appears to involve glycogen sparing through increased fatty acid utilization. Copyright © 2011 S. Karger AG, Basel.

  9. Disinfection by-product formation of UV treated swimming pool water

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Hansen, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2015-01-01

    Water samples from 3 indoor swimming pool facilities were tested to evaluate UV-induced effects on swimming pool water chemistry. Concentration change of several DBPs was investigated in experiments including medium pressure UV treatment with and without chlorine and post-UV chlorination. Post-UV...

  10. Propulsive force calculations in swimming frogs I. A momentum-impulse approach

    NARCIS (Netherlands)

    Nauwelaerts, S; Stamhuis, EJ; Aerts, P

    Frogs are animals that are capable of locomotion in two physically different media, aquatic and terrestrial. A comparison of the kinematics of swimming frogs in a previous study revealed a difference in propulsive impulse between jumping and swimming. To explore this difference further, we

  11. Evolution of Gamete Motility Differences I. Relation Between Swimming Speed and Pheromonal Attraction

    NARCIS (Netherlands)

    Hoekstra, Rolf F.; Janz, Robert F.; Schilstra, A.J.

    1984-01-01

    An analysis is made using population genetic models of the evolution of gamete motility differences as a consequence of a pheromonal gametic approach mechanism. A stable swimming speed dimorphism may arise via disruptive selection on swimming speed, resulting from selection favouring a high

  12. Genotoxic Effects in Swimmers Exposed to Disinfection By-products in Indoor Swimming Pool

    Science.gov (United States)

    BACKGROUND: Exposure to disinfection by-products (DBPs) in drinking water has been associated with cancer risk, and a recent study found an increased bladder cancer risk among subjects attending swimming pools. OBJECTIVES: To evaluate whether swimming in pools is associated with ...

  13. A coupled oscillator model describes normal and strange zooplankton swimming behaviour

    NARCIS (Netherlands)

    Ringelberg, J.; Lingeman, R.

    2003-01-01

    "Normal" swimming in marine and freshwater zooplankton is often intermittent with active upward and more passive downward displacements. In the freshwater cladoceran Daphnia, the pattern is sometimes regular enough to demonstrate the presence of a rhythm. Abnormal swimming patterns were also

  14. The Impact of Immediate Verbal Feedback on the Improvement of Swimming Technique

    Science.gov (United States)

    Zatoń, Krystyna; Szczepan, Stefan

    2014-01-01

    The present research attempts to ascertain the impact of immediate verbal feedback (IVF) on modifications of stroke length (SL). In all swimming styles, stroke length is considered an essential kinematic parameter of the swimming cycle. It is important for swimming mechanics and energetics. If SL shortens while the stroke rate (SR) remains unchanged or decreases, the temporal-spatial structure of swimming is considered erroneous. It results in a lower swimming velocity. Our research included 64 subjects, who were divided into two groups: the experimental – E (n=32) and the control – C (n=32) groups. A pretest and a post-test were conducted. The subjects swam the front crawl over the test distance of 25m at Vmax. Only the E group subjects were provided with IVF aiming to increase their SL. All tests were filmed by two cameras (50 samples•s-1). The kinematic parameters of the swimming cycle were analyzed using the SIMI Reality Motion Systems 2D software (SIMI Reality Motion Systems 2D GmbH, Germany). The movement analysis allowed to determine the average horizontal swimming velocity over 15 meters. The repeated measures analysis of variance ANOVA with a post-hoc Tukey range test demonstrated statistically significant (pswimming velocity. IVF brought about a 6.93% (Simi method) and a 5.09% (Hay method) increase in SL, as well as a 2.92% increase in swimming velocity. PMID:25114741

  15. Swimming near the substrate: a simple robotic model of stingray locomotion

    International Nuclear Information System (INIS)

    Blevins, Erin; Lauder, George V

    2013-01-01

    Studies of aquatic locomotion typically assume that organisms move through unbounded fluid. However, benthic fishes swim close to the substrate and will experience significant ground effects, which will be greatest for fishes with wide spans such as benthic batoids and flatfishes. Ground effects on fixed-wing flight are well understood, but these models are insufficient to describe the dynamic interactions between substrates and undulating, oscillating fish. Live fish alter their swimming behavior in ground effect, complicating comparisons of near-ground and freestream swimming performance. In this study, a simple, stingray-inspired physical model offers insights into ground effects on undulatory swimmers, contrasting the self-propelled swimming speed, power requirements, and hydrodynamics of fins swimming with fixed kinematics near and far from a solid boundary. Contrary to findings for gliding birds and other fixed-wing fliers, ground effect does not necessarily enhance the performance of undulating fins. Under most kinematic conditions, fins do not swim faster in ground effect, power requirements increase, and the cost of transport can increase by up to 10%. The influence of ground effect varies with kinematics, suggesting that benthic fish might modulate their swimming behavior to minimize locomotor penalties and incur benefits from swimming near a substrate. (paper)

  16. Metaphoric Perception of Coach Candidates towards Swimming Discipline: A Qualitative, Cognitive Research

    Science.gov (United States)

    Gündogdu, Cemal; Aygün, Yalin

    2018-01-01

    This research evinces the value of the multidimensional perceptions of the metaphors towards swimming discipline and its relevant certain contexts according to swimming coach candidates. In this article, we used qualitative research paradigm away from positivist approaches to describe and interpret stories and personal experiences of the…

  17. Effective propulsion in swimming: grasping the hydrodynamics of hand and arm movements

    NARCIS (Netherlands)

    van Houwelingen, J.; Schreven, S.; Smeets, J.J.B.; Clercx, H.J.H.; Beek, P.J.

    2017-01-01

    A literature review is presented about the hydrodynamic effects of different hand and arm movements during swimming with the aim to identify lacunae in current methods and knowledge, and to distil practical guidelines for coaches and swimmers seeking to increase swimming speed. Experimental and

  18. Observations on side-swimming rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems

    Science.gov (United States)

    During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRAS), it was observed that rainbow trout Oncorhynchus mykiss in all WRAS exhibited a higher-than-normal prevalence of side-swimming (i.e. controlled, forward swimming, but with misaligned orientation suc...

  19. Effects of Swim Stress on Neophobia and Reconditioning Using a Conditioned Taste Aversion Procedure

    Science.gov (United States)

    Walker, Jennifer M.; Ramsey, Ashley K.; Fowler, Stephanie W.; Schachtman, Todd R.

    2012-01-01

    Previous research has found that swim stress during a classical conditioning trial attenuates conditioned taste aversion (CTA). In the current study, rats were used to examine the effects of inescapable swim stress on the habituation of neophobia to a flavored solution and reacquisition of an extinguished conditioned taste aversion. In Experiment…

  20. Swimming and Children with Attention-Deficit Hyperactive Disorder: A Winning Combination

    Science.gov (United States)

    Dail, Teresa; Smith, Caroline

    2016-01-01

    The benefits of swimming for children with disabilities include improved motor skills, physical fitness, executive brain function and improved social skills. Swimming can also be an activity that provides a positive environment for children suffering from attention-deficit hyperactive disorder (ADHD). This article provides an overview of ADHD and…

  1. Effect of horizontal strong static magnetic field on swimming behaviour of Paramecium caudatum

    Science.gov (United States)

    Fujiwara, Yoshihisa; Tomishige, Masahiko; Itoh, Yasuhiro; Fujiwara, Masao; Shibata, Naho; Kosaka, Toshikazu; Hosoya, Hiroshi; Tanimoto, Yoshifumi

    2006-05-01

    Effect of horizontal strong static magnetic field on swimming behaviour of Paramecium caudatum was studied by using a superconducting magnet. Around a centre of a round vessel, random swimming at 0 T and aligned swimming parallel to the magnetic field (MF) of 8 T were observed. Near a wall of the vessel, however, swimming round and round along the wall at 0 T and aligned swimming of turning at right angles upon collision with the wall, which was remarkable around 1-4 T, were detected. It was experimentally revealed that the former MF-induced parallel swimming at the vessel centre was caused physicochemically by the parallel magnetic orientation of the cell itself. From magnetic field dependence of the extent of the orientation, the magnetic susceptibility anisotropy (χ ∥-χ ⊥) was first obtained to be 3.4× 10-23 emu cell-1 at 298 K for Paramecium caudatum. The orientation of the cell was considered to result from the magnetic orientation of the cell membrane. On the other hand, although mechanisms of the latter swimming near the vessel wall regardless of the absence and presence of the magnetic field are unclear at present, these experimental results indicate that whether the cell exists near the wall alters the magnetic field effect on the swimming in the horizontal magnetic field.

  2. Forced sustained swimming exercise at optimal speed enhances growth of juvenile yellowtail kingfish (Seriola lalandi)

    NARCIS (Netherlands)

    Palstra, A.P.; Mes, D.; Kusters, K.; Roques, J.A.C.; Flik, G.; Kloet, K.; Blonk, R.J.W.

    2015-01-01

    Swimming exercise at optimal speed may optimize growth performance of yellowtail kingfish in a recirculating aquaculture system. Therefore, optimal swimming speeds (U-opt in m s(-1) or body lengths s(-1), BL s(-1)) were assessed and then applied to determine the effects of long-term forced and

  3. Escape from viscosity : the kinematics and hydrodynamics of copepod foraging and escape swimming

    NARCIS (Netherlands)

    van Duren, LA; Videler, JJ

    Feeding and escape swimming in adult females of the calanoid copepod. Temora lopgicornis Muller were investigated and compared. Swimming velocities were calculated using a 3-D filming setup., Foraging velocities ranged between 2 and 6 min s(-1), while maximum velocities of up to 80 mm s(-1) were

  4. Effects of 8-Week Training on Aerobic Capacity and Swimming Performance of Boys Aged 12 Years

    Science.gov (United States)

    Zarzeczny, Ryszard; Kuberski, Mariusz; Deska, Agnieszka; Zarzeczna, Dorota; Rydz, Katarzyna; Lewandowska, Anna; Balchanowski, Tomasz; Bosiacki, Janusz

    2011-01-01

    Study aim: To assess the effects of 8-week endurance training in swimming on work capacity of boys aged 12 years. Material and methods: The following groups of schoolboys aged 12 years were studied: untrained control (UC; n = 14) and those training swimming for two years. The latter ones were subjected to 8-week training in classical style (CS; n…

  5. Photolytic removal of DBPs by medium pressure UV in swimming pool water

    OpenAIRE

    Hansen, Kamilla Marie Speht; Zortea, R.; Piketty, A.; Rodriguez Vega, S.; Andersen, Henrik Rasmus

    2013-01-01

    Medium pressure UV is used for controlling the concentration of combined chlorine (chloramines) in many public swimming pools. Little is known about the fate of other disinfection by-products (DBPs) in UV treatment. Photolysis by medium pressure UV treatment was investigated for 12 DBPs reported to be found in swimming pool water: chloroform, bromodichloromethane, dibromochloromethane, bromoform, dichloroacetonitrile, bromochloroacetonitrile, dibromoacetronitrile, trichloroacetonitrile, trich...

  6. Solar-heated municipal swimming pools, a case study: Dade County, Florida

    Science.gov (United States)

    Levin, M.

    1981-09-01

    The installation of a solar energy system to heat the water in the swimming pool in one of Dade County, Florida's major parks is described. The mechanics of solar heated swimming pools are explained. The solar heating system consists of 216 unglazed polypropylene tube collectors, a differential thermostat, and the distribution system. The systems performance and economics as well as future plants are discussed.

  7. Analysis of swimming performance from physical, physiological, and biomechanical parameters in young swimmers.

    Science.gov (United States)

    Jürimäe, Jaak; Haljaste, Kaja; Cicchella, Antonio; Lätt, Evelin; Purge, Priit; Leppik, Aire; Jürimäe, Toivo

    2007-02-01

    The purpose of this study was to examine the influence of the energy cost of swimming, body composition, and technical parameters on swimming performance in young swimmers. Twenty-nine swimmers, 15 prepubertal (11.9 +/- 0.3 years; Tanner Stages 1-2) and 14 pubertal (14.3 +/- 1.4 years; Tanner Stages 3-4) boys participated in the study. The energy cost of swimming (Cs) and stroking parameters were assessed over maximal 400-m front-crawl swimming in a 25-m swimming pool. The backward extrapolation technique was used to evaluate peak oxygen consumption (VO2peak). A stroke index (SI; m2 . s(-1) . cycles(-1)) was calculated by multiplying the swimming speed by the stroke length. VO2peak results were compared with VO2peak test in the laboratory (bicycle, 2.86 +/- 0.74 L/min, vs. in water, 2.53 +/- 0.50 L/min; R2 = .713; p = .0001). Stepwise-regression analyses revealed that SI (R2 = .898), in-water VO2peak (R2 = .358), and arm span (R2 = .454) were the best predictors of swimming performance. The backward-extrapolation method could be used to assess VO2peak in young swimmers. SI, arm span, and VO2peak appear to be the major determinants of front-crawl swimming performance in young swimmers.

  8. Simulated front crawl swimming performance related to critical speed and critical power

    NARCIS (Netherlands)

    Toussaint, H.M.; Wakayoshi, K.; Hollander, A.P.; Ogita, F.

    1998-01-01

    Purpose: Competitive pool swimming events range in distance from 50 to 1500 m. Given the difference in performance times (±23-1000 s), the contribution of the aerobic and anaerobic energy systems changes considerably with race distance. In training practice the regression line between swimming

  9. Caffeine in Boston Harbor past and present, assessing its utility as a tracer of wastewater contamination in an urban estuary

    Science.gov (United States)

    Sites throughout Boston Harbor were analyzed for caffeine to assess its utility as a tracer in identifying sources of sanitary wastewater. Caffeine ranged from 15 ng/L in the outer harbor to a high of 185 ng/L in the inner harbor. Inner harbor concentrations were a result of comb...

  10. Heat from harbor to city; Warmte van haven naar stad

    Energy Technology Data Exchange (ETDEWEB)

    Roggen, M. (ed.)

    2004-09-01

    The Rotterdam harbor area is perfect for an industrial heat distribution network. Numerous major heat producers and many potential consumers of all sizes group together in this industrial area. The new Heat Company ('Warmtebedrijf') is making a detailed business plan to build a heat distribution system. [Dutch] Als er een regio is waar een industrieel warmtenet voor de hand ligt, is het het Rotterdamse havengebied wel. Tal van grote warmteproducenten en een woud aan kleinere en grotere afnemers zijn praktisch buren. Om handen en voeten te geven aan dit op papier mooie idee, stelt het kersverse Warmtebedrijf io een gedetailleerd businessplan op.

  11. Hydraulic modeling of stream channels and structures in Harbor and Crow Hollow Brooks, Meriden, Connecticut

    Science.gov (United States)

    Weiss, Lawrence A.; Sears, Michael P.; Cervione, Michael A.

    1994-01-01

    Effects of urbanization have increased the frequency and size of floods along certain reaches of Harbor Brook and Crow Hollow Brook in Meriden, Conn. A floodprofile-modeling study was conducted to model the effects of selected channel and structural modifications on flood elevations and inundated areas. The study covered the reach of Harbor Brook downstream from Interstate 691 and the reach of Crow Hollow Brook downstream from Johnson Avenue. Proposed modifications, which include changes to bank heights, channel geometry, structural geometry, and streambed armoring on Harbor Brook and changes to bank heights on Crow Hollow Brook, significantly lower flood elevations. Results of the modeling indicate a significant reduction of flood elevations for the 10-year, 25-year, 35-year, 50-year, and 100-year flood frequencies using proposed modifications to (1 ) bank heights between Harbor Brook Towers and Interstate 691 on Harbor Brook, and between Centennial Avenue and Johnson Avenue on Crow Hollow Brook; (2) channel geometry between Coe Avenue and Interstate 69 1 on Harbor Brook; (3) bridge and culvert opening geometry between Harbor Brook Towers and Interstate 691 on Harbor Brook; and (4) channel streambed armoring between Harbor Brook Towers and Interstate 691 on Harbor Brook. The proposed modifications were developed without consideration of cost-benefit ratios.

  12. EFFECTIVENESS OF DOUBLE WASH SWIM-UP VERSUS DOUBLE DENSITY GRADIENT SWIM-UP TECHNIQUE OF SPERM PREPARATION IN IN VITRO FERTILISATION

    OpenAIRE

    Srinivas Sangisapu; Sandeep Karunakaran; Ashok Kumar Pillai

    2017-01-01

    BACKGROUND Recovery of optimum number of good quality of spermatozoa is an important component of In Vitro Fertilisation (IVF). This is achieved by sperm preparation methods involving separation and recovery of capacitated sperms. Double Wash Swim-up (DWSU) and Double Density Gradient Swim-up (DDGSU) are two most accepted methods. Cochrane systematic review (2007) finds no clear benefit of one method over the other in Intrauterine Insemination (IUI). Systematic review on effective...

  13. Optimum swimming pathways of fish spawning migrations in rivers

    Science.gov (United States)

    McElroy, Brandon; DeLonay, Aaron; Jacobson, Robert

    2012-01-01

    Fishes that swim upstream in rivers to spawn must navigate complex fluvial velocity fields to arrive at their ultimate locations. One hypothesis with substantial implications is that fish traverse pathways that minimize their energy expenditure during migration. Here we present the methodological and theoretical developments necessary to test this and similar hypotheses. First, a cost function is derived for upstream migration that relates work done by a fish to swimming drag. The energetic cost scales with the cube of a fish's relative velocity integrated along its path. By normalizing to the energy requirements of holding a position in the slowest waters at the path's origin, a cost function is derived that depends only on the physical environment and not on specifics of individual fish. Then, as an example, we demonstrate the analysis of a migration pathway of a telemetrically tracked pallid sturgeon (Scaphirhynchus albus) in the Missouri River (USA). The actual pathway cost is lower than 105 random paths through the surveyed reach and is consistent with the optimization hypothesis. The implication—subject to more extensive validation—is that reproductive success in managed rivers could be increased through manipulation of reservoir releases or channel morphology to increase abundance of lower-cost migration pathways.

  14. Physiological Adaptations to Training in Competitive Swimming: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Costa Mário J.

    2015-12-01

    Full Text Available The purpose of this systematic review was to summarize longitudinal studies on swimming physiology and get implications for daily practice. A computerized search of databases according to the PRISMA statement was employed. Studies were screened for eligibility on inclusion criteria: (i present two testing points; (ii on swimming physiology; (iii using adult elite swimmers; (iv no case-studies or with small sample sizes. Two independent reviewers used a checklist to assess the methodological quality of the studies. Thirty-four studies selected for analysis were gathered into five main categories: blood composition (n=7, endocrine secretion (n=11, muscle biochemistry (n=7, cardiovascular response (n=8 and the energetic profile (n=14. The mean quality index was 10.58 ± 2.19 points demonstrating an almost perfect agreement between reviewers (K = 0.93. It can be concluded that the mixed findings in the literature are due to the diversity of the experimental designs. Micro variables obtained at the cellular or molecular level are sensitive measures and demonstrate overtraining signs and health symptoms. The improvement of macro variables (i.e. main physiological systems is limited and may depend on the athletes’ training background and experience.

  15. Role of overexpressed CFA/I fimbriae in bacterial swimming

    International Nuclear Information System (INIS)

    Cao, Ling; Lim, Timothy; Jun, SangMu; Riccardi, Carol; Yang, Xinghong; Suo, Zhiyong; Deliorman, Muhammedin; Kellerman, Laura; Avci, Recep

    2012-01-01

    Enterotoxigenic Escherichia coli CFA/I is a protective antigen and has been overexpressed in bacterial vectors, such as Salmonella Typhimurium H683, to generate vaccines. Effects that overexpressed CFA/I may engender on the bacterial host remain largely unexplored. To investigate, we constructed a high CFA/I expression strain, H683-pC2, and compared it to a low CFA/I expression strain, H683-pC, and to a non-CFA/I expression strain, H683-pY. The results showed that H683-pC2 was less able to migrate into semisolid agar (0.35%) than either H683-pC or H683-pY. Bacteria that migrated showed motility halo sizes of H683-pC2 < H683-pC < H683-pY. In the liquid culture media, H683-pC2 cells precipitated to the bottom of the tube, while those of H683-pY did not. In situ imaging revealed that H683-pC2 bacilli tended to auto-agglutinate within the semisolid agar, while H683-pY bacilli did not. When the cfaBE fimbrial fiber encoding genes were deleted from pC2, the new plasmid, pC2(-), significantly recovered bacterial swimming capability. Our study highlights the negative impact of overexpressed CFA/I fimbriae on bacterial swimming motility. (paper)

  16. The kinematics of swimming and relocation jumps in copepod nauplii

    DEFF Research Database (Denmark)

    Borg, Marc Andersen; Bruno, Eleonora; Kiørboe, Thomas

    2012-01-01

    Copepod nauplii move in a world dominated by viscosity. Their swimming-by-jumping propulsion mode, with alternating power and recovery strokes of three pairs of cephalic appendages, is fundamentally different from the way other microplankters move. Protozoans move using cilia or flagella, and cop......Copepod nauplii move in a world dominated by viscosity. Their swimming-by-jumping propulsion mode, with alternating power and recovery strokes of three pairs of cephalic appendages, is fundamentally different from the way other microplankters move. Protozoans move using cilia or flagella...... of pelagic copepods: Temora longicornis, Oithona davisae and Acartia tonsa. The kinematics of jumping is similar between the three species. Jumps result in a very erratic translation with no phase of passive coasting and the nauplii move backwards during recovery strokes. This is due to poorly synchronized...... recovery strokes and a low beat frequency relative to the coasting time scale. For the same reason, the propulsion efficiency of the nauplii is low. Given the universality of the nauplius body plan, it is surprising that they seem to be inefficient when jumping, which is different from the very efficient...

  17. Thin Layer Sensory Cues Affect Antarctic Krill Swimming Kinematics

    Science.gov (United States)

    True, A. C.; Webster, D. R.; Weissburg, M. J.; Yen, J.

    2013-11-01

    A Bickley jet (laminar, planar free jet) is employed in a recirculating flume system to replicate thin shear and phytoplankton layers for krill behavioral assays. Planar laser-induced fluorescence (LIF) and particle image velocimetry (PIV) measurements quantify the spatiotemporal structure of the chemical and free shear layers, respectively, ensuring a close match to in situ hydrodynamic and biochemical conditions. Path kinematics from digitized trajectories of free-swimming Euphausia superba examine the effects of hydrodynamic sensory cues (deformation rate) and bloom level phytoplankton patches (~1000 cells/mL, Tetraselamis spp.) on krill behavior (body orientation, swimming modes and kinematics, path fracticality). Krill morphology is finely tuned for receiving and deciphering both hydrodynamic and chemical information that is vital for basic life processes such as schooling behaviors, predator/prey, and mate interactions. Changes in individual krill behavior in response to ecologically-relevant sensory cues have the potential to produce population-scale phenomena with significant ecological implications. Krill are a vital trophic link between primary producers (phytoplankton) and larger animals (seabirds, whales, fish, penguins, seals) as well as the subjects of a valuable commercial fishery in the Southern Ocean; thus quantifying krill behavioral responses to relevant sensory cues is an important step towards accurately modeling Antarctic ecosystems.

  18. Model of skin friction enhancement in undulatory swimming

    Science.gov (United States)

    Ehrenstein, Uwe; Eloy, Christophe

    2012-11-01

    To estimate the energetic cost of undulatory swimming, it is crucial to evaluate the drag forces originating from skin friction. This topic has been controversial for decades, some claiming that animals use ingenious mechanisms to reduce the drag and others hypothesizing that the undulatory motion induces a drag increase because of the compression of the boundary layers. In this paper, we examine this latter hypothesis, known as the ``Bone-Lighthill boundary-layer thinning hypothesis''. Considering a plate of section s moving perpendicular to itself at velocity U⊥ and applying the boundary-layer approximation for the incoming flow, the drag force per unit surface is shown to scale as √{U⊥ / s }. An analogous two-dimensional Navier-Stokes problem by artificially accelerating the flow in a channel of finite height is solved numerically, showing the robustness of the analytical results. Solving the problem for an undulatory plate motion similar to fish swimming, we find a drag enhancement which can be estimated to be of the order of 20 to 100%, depending on the geometry and the motion. M.J. Lighthill, Proc. R. Soc. Lond. B 179, 125 (1971).

  19. Environmental calcium and variation in yolk sac size influence swimming performance in larval lake sturgeon (Acipenser fulvescens)

    DEFF Research Database (Denmark)

    Deslauriers, David; Svendsen, Jon Christian; Genz, Janet

    2018-01-01

    , because the yolk sac is likely to affect drag forces during swimming. Testing swimming performance of larval A. fulvescens reared in four different calcium treatments spanning the range of 4-132 mg l-1 [Ca2+], this study found no treatment effects on the sprint swimming speed. A novel test of volitional...... reduced swimming performance and could be more susceptible to predation or premature downstream drift. Our study reveals how environmental factors and phenotypic variation influence locomotor performance in a larval fish....

  20. Environmental burdens of a Finnish indoor swimming pool; Uimahallin ympaeristoekuormitukset

    Energy Technology Data Exchange (ETDEWEB)

    Vaahterus, T.; Saari, A.

    2001-07-01

    In this study the environmental burdens of a Finnish indoor swimming pool generated by its energy consumption were calculated. The calculations were made by using a calculation method based on LCA methodology. Calculations were made of 50 years period. The energy consumption dating from the time of the indoor swimming pool causes towards the gross-floor area a nearly four times bigger environmental load than for example a block of flats and indoor ice- skating rink. On a block of flats and indoor ice-skating rink the energy consumption dating from the time of the use causes more than 90 % of the environmental burdens of the whole life span. One can suppose that at the indoor swimming pool the share of the energy consumption dating from the time of the use only is emphasized. In this study confine therefore to dealing with the environmental loads caused only by the energy consumption dating from the time of the use. The results of these calculations showed that the energy flow of the life cycle energy consumption was 193 000 MJ/brm{sup 2}. 11,2 ton per gross-floor area CO{sub 2} equivalents, 21 kg per gross-floor area SO{sub 2} equivalents and 290 g per gross-floor area ethene equivalents of environmental burdens were caused. The main factor causing the most environmental loads were the need of heating energy. The need of heating energy produced 75 % of the CO{sub 2} equivalents, 70 % of the SO{sub 2} equivalents and 59 % of the ethene equivalents. The need of the electric energy produced 23 % of the CO{sub 2} equivalents, 23 % of the SO{sub 2} equivalents and 17 % of the ethene equivalents. Of the heating energy the share of the warming of water was 56 %. The most significant part of the electric energy were consumed in the use of the sauna stoves and vapor sauna (31 %) and heating pumps and water elements (30 %). Almost all (87 %) of the energy, consumed during the life cycle, was produced with non-renewable energy sources. The source information of the energy was

  1. Swimming in a contained space: Understanding the experience of indoor lap swimmers.

    Science.gov (United States)

    Ward, Miranda

    2017-07-01

    Drawing on ethnographic work, this paper explores the convergence of bodies, materialities and practices found at the indoor swimming pool - a space that has not often been the subject of geographical study, in spite of the fact that swimming is one of the most popular forms of exercise in countries such as the UK. The paper focuses on the "contained" nature of the indoor pool environment, examining the distinct experience this can create for lap swimmers. This focus is placed in the context of a broader politics of exercise, with an emphasis on the popularity and potential benefits of swimming, as well as less encouraging facts about participation and facility provision, suggesting that in order to encourage further uptake of swimming and preservation of swimming facilities the voices and experiences of regular swimmers should be considered. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Noncontact Cohesive Swimming of Bacteria in Two-Dimensional Liquid Films.

    Science.gov (United States)

    Li, Ye; Zhai, He; Sanchez, Sandra; Kearns, Daniel B; Wu, Yilin

    2017-07-07

    Bacterial swimming in confined two-dimensional environments is ubiquitous in nature and in clinical settings. Characterizing individual interactions between swimming bacteria in 2D confinement will help to understand diverse microbial processes, such as bacterial swarming and biofilm formation. Here we report a novel motion pattern displayed by flagellated bacteria in 2D confinement: When two nearby cells align their moving directions, they tend to engage in cohesive swimming without direct cell body contact, as a result of hydrodynamic interaction but not flagellar intertwining. We further found that cells in cohesive swimming move with higher directional persistence, which can increase the effective diffusivity of cells by ∼3 times as predicted by computational modeling. As a conserved behavior for peritrichously flagellated bacteria, cohesive swimming in 2D confinement may be key to collective motion and self-organization in bacterial swarms; it may also promote bacterial dispersal in unsaturated soils and in interstitial space during infections.

  3. Pop up satellite tags impair swimming performance and energetics of the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Methling, Caroline; Tudorache, Christian; Skov, Peter Vilhelm

    2011-01-01

    Pop-up satellite archival tags (PSATs) have recently been applied in attempts to follow the oceanic spawning migration of the European eel. PSATs are quite large, and in all likelihood their hydraulic drag constitutes an additional cost during swimming, which remains to be quantified, as does...... the potential implication for successful migration. Silver eels (L(T)=598.6 +/- 29 mm SD, N = 9) were subjected to swimming trials in a Steffensen-type swim tunnel at increasing speeds of 0.3-0.9 body lengths s(-1), first without and subsequently with, a scaled down PSAT dummy attached. The tag significantly...... increased oxygen consumption (MO(2)) during swimming and elevated minimum cost of transport (COT(min)) by 26 Standard (SMR) and active metabolic rate (AMR) as well as metabolic scope remained unaffected, suggesting that the observed effects were caused by increased drag. Optimal swimming speed (U...

  4. Radio-transmitted electromyogram signals as indicators of swimming speed in lake trout and brown trout

    DEFF Research Database (Denmark)

    Thorstad, E.B.; Økland, F.; Koed, Anders

    2000-01-01

    Swimming speed and average electromyogram (EMG) pulse intervals were highly correlated in individual lake trout Salvelinus namaycush (r(2)=0.52-0.89) and brown trout Salmo trutta (r(2)=0.45-0.96). High correlations were found also for pooled data in both lake trout (r(2)=0.90) and brown trout...... of the Ema stock (r(2)=0.96) and Laerdal stock (r(2)=0.96). The linear relationship between swimming speed and average EMG pulse intervals differed significantly among lake trout and the brown trout stocks. This successful calibration of EMGs to swimming speed opens the possibility of recording swimming...... speed of free swimming lake trout and brown trout in situ. EMGs can also be calibrated to oxygen consumption to record energy expenditure. (C) 2000 The Fisheries Society of the British Isles...

  5. Benefits of carbon dioxide as pH reducer in chlorinated indoor swimming pools.

    Science.gov (United States)

    Gomà, Anton; Guisasola, Albert; Tayà, Carlota; Baeza, Juan A; Baeza, Mireia; Bartrolí, Albert; Lafuente, Javier; Bartrolí, Jordi

    2010-06-01

    Carbon dioxide is seldom used as pH reducer in swimming pools. Nevertheless it offers two interesting advantages. First, its use instead of the usual hydrochloric acid avoids the characteristic and serious accident of mixing the disinfectant with that strong acid, which forms a dangerous chlorine gas cloud and, second, it allows the facility to become slightly a depository of that greenhouse gas. This work introduces the experience of using CO(2) as pH reducer in real working swimming pools, showing three more advantages: lower chlorine consumption, lower presence of oxidants in the air above the swimming pool and a diminished formation of trihalomethanes in the swimming pool water. Experiments lasted 4years and they were run in three swimming pools in the Barcelona area, where the conventional system based upon HCl and a system based upon CO(2) were consecutively exchanged.

  6. Energetics and biomechanics as determining factors of swimming performance: updating the state of the art.

    Science.gov (United States)

    Barbosa, Tiago M; Bragada, José A; Reis, Víctor M; Marinho, Daniel A; Carvalho, Carlos; Silva, António J

    2010-03-01

    The biophysical determinants related to swimming performance are one of the most attractive topics within swimming science. The aim of this paper was to do an update of the "state of art" about the interplay between performance, energetic and biomechanics in competitive swimming. Throughout the manuscript some recent highlights are described: (i) the relationship between swimmer's segmental kinematics (segmental velocities, stroke length, stroke frequency, stroke index and coordination index) and his center of mass kinematics (swimming velocity and speed fluctuation); (ii) the relationships between energetic (energy expenditure and energy cost) and swimmer's kinematics; and (iii) the prediction of swimming performance derived from above mentioned parameters. Copyright 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  7. 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

  8. Effect of wearing clothes on oxygen uptake and ratings of perceived exertion while swimming.

    Science.gov (United States)

    Choi, S W; Kurokawa, T; Ebisu, Y; Kikkawa, K; Shiokawa, M; Yamasaki, M

    2000-07-01

    For a comparative study between swimming in swimwear (control-sw) and swimming in clothes (clothes-sw), oxygen uptake (VO2) and ratings of perceived exertion (RPE) were measured. The subjects were six male members of a university swimming team. Three swimming strokes--the breaststroke, the front crawl stroke and the elementary backstroke--were applied. With regards to clothes-sw, swimmers wore T-shirts, sportswear (shirt and pants) over swimwear and running shoes. In both cases of control-sw and clothes-sw, the VO2 was increased exponentially with increased swimming speed. The VO2 of the subjects during the clothed tests did not exceed 1.4 times of that in the case of control-sw at swimming speeds below 0.3 m/s. As swimming speeds increased, VO2 difference in both cases increased. Consequently, VO2 in the clothed tests was equal to 1.5-1.6 times and 1.5-1.8 times of that in the swimwear tests at speeds of 0.5 and 0.7 m/s, respectively. At speeds below 0.6 m/s in clothes-sw, the breaststroke showed lower VO2 than the front crawl stroke, and the elementary backstroke showed higher VO2 than the other two swimming strokes. RPE increased linearly with %peak VO2. In addition, any RPE differences among the three swimming strokes were not shown in the control-sw tests. At an exercise intensity above 60 %peak VO2, clothed swimmers showed slightly higher RPE in the front crawl stroke compared to that in the two other swimming strokes.

  9. Changes in the flagellar bundling time account for variations in swimming behavior of flagellated bacteria in viscous media

    NARCIS (Netherlands)

    Qu, Zijie; Temel, Fatma Zeynep; Henderikx, Rene; Breuer, Kenneth S.

    2018-01-01

    Although the motility of the flagellated bacteria, Escherichia coli, has been widely studied, the effect of viscosity on swimming speed remains controversial. The swimming mode of wild-type E. coli is often idealized as a run-and-tumble sequence in which periods of swimming at a constant speed are

  10. Microbial quality of swimming pool water with treatment without disinfection, with ultrafiltration, with UV-based treatment and with chlorination

    NARCIS (Netherlands)

    Keuten, M.G.A.; Peters, M.C.F.M.; van Dijk, J.C.; van Loosdrecht, Mark C.M.; Rietveld, L.C.

    2017-01-01

    Swimming pools are traditionally disinfected with a residual disinfectant such as sodium hypochlorite. Nowadays, swimming water without a residual disinfectant is increasingly popular, as can be seen by the growing number of (natural) swimming ponds (Weilandt 2015), but health risks for bathers do

  11. Bluff evolution along coastal drumlins: Boston Harbor Islands, Massachusetts

    Science.gov (United States)

    Himmelstoss, E.A.; FitzGerald, D.M.; Rosen, P.S.; Allen, J.R.

    2006-01-01

    A series of partially drowned drumlins forms the backbone of the inner islands within Boston Harbor. The shoreline of these rounded glacial deposits is composed of actively retreating bluffs formed by continual wave attack. Comparisons of bluffs reveal variability in their height and lateral extent, as well as in the dominant mechanism causing their retreat. Two processes are responsible for bluff erosion and yield distinct bluff morphologies: (1) wave attack undercuts the bluff and causes episodic slumping, yielding planar bluff slopes, and (2) subaerial processes such as rainfall create irregular slopes characterized by rills and gullies. We propose a model of drumlin bluff evolution that is based on processes of erosion and physical characteristics such as bluff height, slope morphology, and the orientation of the bluff with respect to the long axis of the drumlin and its topographic crest. The four phases of drumlin bluff evolution consist of (1) initial formation of bluff, with retreat dominated by wave notching and slumping processes; (2) rill and gully development as bluff heights exceed 10 m and slumped sediment at bluff base inhibits wave attack; (3) return of wave notching and slumping as bluff heights decrease; and (4) final development of boulder retreat lag as last remnants of drumlin are eroded by wave action. These phases capture the important physical processes of drumlin evolution in Boston Harbor and could apply to other eroding coastal drumlin deposits.

  12. New world bats harbor diverse influenza A viruses.

    Directory of Open Access Journals (Sweden)

    Suxiang Tong

    Full Text Available Aquatic birds harbor diverse influenza A viruses and are a major viral reservoir in nature. The recent discovery of influenza viruses of a new H17N10 subtype in Central American fruit bats suggests that other New World species may similarly carry divergent influenza viruses. Using consensus degenerate RT-PCR, we identified a novel influenza A virus, designated as H18N11, in a flat-faced fruit bat (Artibeus planirostris from Peru. Serologic studies with the recombinant H18 protein indicated that several Peruvian bat species were infected by this virus. Phylogenetic analyses demonstrate that, in some gene segments, New World bats harbor more influenza virus genetic diversity than all other mammalian and avian species combined, indicative of a long-standing host-virus association. Structural and functional analyses of the hemagglutinin and neuraminidase indicate that sialic acid is not a ligand for virus attachment nor a substrate for release, suggesting a unique mode of influenza A virus attachment and activation of membrane fusion for entry into host cells. Taken together, these findings indicate that bats constitute a potentially important and likely ancient reservoir for a diverse pool of influenza viruses.

  13. Grace Under Fire: The Army Nurses of Pearl Harbor, 1941.

    Science.gov (United States)

    Milbrath, Gwyneth R

    2016-01-01

    Much has been written about the military events of December 7, 1941; however, little has been documented about the nurses' work and experience at Pearl Harbor, Hawaii. The aerial assault on Pearl Harbor was the first time in US history that Army nurses had been on the front line of battle. Nurses quickly triaged and stabilized those who could be saved, and provided compassion and comfort to those who were dying, in an environment where the nurses were unsure of their own survival. Traditional historical methods and a social history framework were used in this investigation. Primary sources included oral histories from the US Army Medical Department Center of History and Heritage and the State of Hawaii's website, Hawaii Aviation. Secondary sources included published books, newspaper articles, military websites, and history texts. Due to the limited bed capacity, Hickam Field Hospital converted to an evacuation hospital. Nurses, physicians, and medical corpsman triaged, stabilized, and transported those likely to survive, while staging the dead behind the building. The emergency room at Tripler Hospital was quickly flooded with patients from the battlefield, but the staff was able to sort patients appropriately to the wards, to the operating room, or provide comfort care as they died. At Schofield Hospital, collaboration between tireless doctors, nurses, and corpsmen was key to providing life-saving surgery and care.

  14. The historical significance of anaesthesia events at Pearl Harbor.

    Science.gov (United States)

    Crowhurst, Ja

    2014-07-01

    Up to the end of World War II, less than 10% of the general anaesthetics administered was with intravenous barbiturates. The remaining 90% of anaesthetics given in the USA were with diethyl ether. In the United Kingdom and elsewhere, chloroform was also popular. Diethyl ether administration was a relatively safe and simple procedure, often delegated to nurses or junior doctors with little or no specific training in anaesthesia. During the Japanese attack on the US bases at Pearl Harbor, with reduced stocks of diethyl ether available, intravenous Sodium Pentothal(®), a most 'sophisticated and complex' drug, was used with devastating effects in many of those hypovolaemic, anaemic and septic patients. The hazards of spinal anaesthesia too were realised very quickly. These effects were compounded by the dearth of trained anaesthetists. This paper presents the significance of the anaesthesia tragedies at Pearl Harbor, and the discovery in the next few years of many other superior drugs that caused medical and other health professionals to realise that anaesthesia needed to be a specialist medical discipline in its own right. Specialist recognition, aided by the foundation of the National Health Service in the UK, the establishment of Faculties of Anaesthesia and appropriate training in pharmacology, physiology and other sciences soon followed. Modern anaesthesiology, as we understand it today, was born and a century or more of ether anaesthesia finally ceased.

  15. Emergence of fatal avian influenza in New England harbor seals

    Science.gov (United States)

    Anthony, S.J.; St. Leger, J. A.; Pugliares, K.; Ip, Hon S.; Chan, J.M.; Carpenter, Z.W.; Navarrete-Macias, I.; Sanchez-Leon, M.; Saliki, J.T.; Pedersen, J.; Karesh, W.; Daszak, P.; Rabadan, R.; Rowles, T.; Lipkin, W.I.

    2012-01-01

    From September to December 2011, 162 New England harbor seals died in an outbreak of pneumonia. Sequence analysis of postmortem samples revealed the presence of an avian H3N8 influenza A virus, similar to a virus circulating in North American waterfowl since at least 2002 but with mutations that indicate recent adaption to mammalian hosts. These include a D701N mutation in the viral PB2 protein, previously reported in highly pathogenic H5N1 avian influenza viruses infecting people. Lectin staining and agglutination assays indicated the presence of the avian-preferred SAα-2,3 and mammalian SAα-2,6 receptors in seal respiratory tract, and the ability of the virus to agglutinate erythrocytes bearing either the SAα-2,3 or the SAα-2,6 receptor. The emergence of this A/harbor seal/Massachusetts/1/2011 virus may herald the appearance of an H3N8 influenza clade with potential for persistence and cross-species transmission.

  16. Physiological demands of a swimming-based video game: Influence of gender, swimming background, and exergame experience.

    Science.gov (United States)

    Soltani, Pooya; Figueiredo, Pedro; Ribeiro, João; Fernandes, Ricardo J; Vilas-Boas, João Paulo

    2017-07-12

    Active video games (exergames) may provide short-term increase in energy expenditure. We explored the effects of gender and prior experience on aerobic and anaerobic energy systems contributions, and the activity profiles of 40 participants playing with a swimming exergame. We recorded oxygen consumption and assessed blood lactate after each swimming technique. We also filmed participants' gameplays, divided them into different phases and tagged them as active or inactive. Anaerobic pathway accounted for 8.9 ± 5.6% of total energy expenditure and although experienced players were less active compared to novice counterparts (η² increase in physiological measures might happen in the beginning of gameplay because of unfamiliarity with the game mechanics. Despite low levels of activity compared to real sport, both aerobic and anaerobic energy systems should be considered in the evaluation of exergames. Game mechanics (involving the whole body) and strategies to minimize pragmatic play might be used for effective and meaningful game experience.

  17. Polycyclic aromatic hydrocarbons and trace elements bounded to airborne PM10 in the harbor of Volos, Greece: Implications for the impact of harbor activities

    Science.gov (United States)

    Manoli, E.; Chelioti-Chatzidimitriou, A.; Karageorgou, K.; Kouras, A.; Voutsa, D.; Samara, C.; Kampanos, I.

    2017-10-01

    Harbors are often characterized by high levels of air pollutants that are emitted from ship traffic and other harbor activities. In the present study, the concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) and trace elements (As, Cd, Ni, Pb, Cr, Mn, Zn, and Fe) bounded to the inhalable particulate matter PM10 were studied in the harbor of Volos, central Greece, during a 2-year period (2014-2015). Seasonal and daily variations were investigated. Moreover, total carcinogenic and mutagenic activities of PAHs were calculated. The effect of major wind sectors (sea, city, industrial, harbor) was estimated to assess the potential contribution of ship traffic and harbor activities, such as scrap metal handling operations. Results showed that the harbor sector (calm winds ≤ 0.5 m s-1) was associated with the highest concentrations of PM10. The harbor sector was also associated with relatively increased levels of trace elements (As, Fe, Cr, Mn, Ni), however the effect of this sector was lower than the corresponding effect of the industrial wind sector. The sea sector showed only a slight increase in B[a]Py and Σ12PAHs, whereas the highest increasing effect for PAHs and traffic-related elements, such as Pb and Zn, was evidenced for the city sector.

  18. Fast, automated measurement of nematode swimming (thrashing without morphometry

    Directory of Open Access Journals (Sweden)

    Sattelle David B

    2009-07-01

    Full Text Available Abstract Background The "thrashing assay", in which nematodes are placed in liquid and the frequency of lateral swimming ("thrashing" movements estimated, is a well-established method for measuring motility in the genetic model organism Caenorhabditis elegans as well as in parasitic nematodes. It is used as an index of the effects of drugs, chemicals or mutations on motility and has proved useful in identifying mutants affecting behaviour. However, the method is laborious, subject to experimenter error, and therefore does not permit high-throughput applications. Existing automation methods usually involve analysis of worm shape, but this is computationally demanding and error-prone. Here we present a novel, robust and rapid method of automatically counting the thrashing frequency of worms that avoids morphometry but nonetheless gives a direct measure of thrashing frequency. Our method uses principal components analysis to remove the background, followed by computation of a covariance matrix of the remaining image frames from which the interval between statistically-similar frames is estimated. Results We tested the performance of our covariance method in measuring thrashing rates of worms using mutations that affect motility and found that it accurately substituted for laborious, manual measurements over a wide range of thrashing rates. The algorithm used also enabled us to determine a dose-dependent inhibition of thrashing frequency by the anthelmintic drug, levamisole, illustrating the suitability of the system for assaying the effects of drugs and chemicals on motility. Furthermore, the algorithm successfully measured the actions of levamisole on a parasitic nematode, Haemonchus contortus, which undergoes complex contorted shapes whilst swimming, without alterations in the code or of any parameters, indicating that it is applicable to different nematode species, including parasitic nematodes. Our method is capable of analyzing a 30 s movie in

  19. Streamwise vortices destabilize swimming bluegill sunfish (Lepomis macrochirus).

    Science.gov (United States)

    Maia, Anabela; Sheltzer, Alex P; Tytell, Eric D

    2015-03-01

    In their natural environment, fish must swim stably through unsteady flows and vortices, including vertical vortices, typically shed by posts in a flow, horizontal cross-flow vortices, often produced by a step or a waterfall in a stream, and streamwise vortices, where the axis of rotation is aligned with the direction of the flow. Streamwise vortices are commonly shed by bluff bodies in streams and by ships' propellers and axial turbines, but we know little about their effects on fish. Here, we describe how bluegill sunfish use more energy and are destabilized more often in flow with strong streamwise vorticity. The vortices were created inside a sealed flow tank by an array of four turbines with similar diameter to the experimental fish. We measured oxygen consumption for seven sunfish swimming at 1.5 body lengths (BL) s(-1) with the turbines rotating at 2 Hz and with the turbines off (control). Simultaneously, we filmed the fish ventrally and recorded the fraction of time spent maneuvering side-to-side and accelerating forward. Separately, we also recorded lateral and ventral video for a combination of swimming speeds (0.5, 1.5 and 2.5 BL s(-1)) and turbine speeds (0, 1, 2 and 3 Hz), immediately after turning the turbines on and 10 min later to test for accommodation. Bluegill sunfish are negatively affected by streamwise vorticity. Spills (loss of heading), maneuvers and accelerations were more frequent when the turbines were on than in the control treatment. These unsteady behaviors, particularly acceleration, correlated with an increase in oxygen consumption in the vortex flow. Bluegill sunfish are generally fast to recover from roll perturbations and do so by moving their pectoral fins. The frequency of spills decreased after the turbines had run for 10 min, but was still markedly higher than in the control, showing that fish partially adapt to streamwise vorticity, but not completely. Coping with streamwise vorticity may be an important energetic

  20. Influenza A(H10N7) Virus in Dead Harbor Seals, Denmark

    DEFF Research Database (Denmark)

    Krog, Jesper Schak; Hansen, Mette Sif; Holm, Elisabeth

    2015-01-01

    Since April 2014, an outbreak of influenza in harbor seals has been ongoing in northern Europe. In Denmark during June-August, 152 harbor seals on the island of Anholt were found dead from severe pneumonia. We detected influenza A(H10N7) virus in 2 of 4 seals examined.......Since April 2014, an outbreak of influenza in harbor seals has been ongoing in northern Europe. In Denmark during June-August, 152 harbor seals on the island of Anholt were found dead from severe pneumonia. We detected influenza A(H10N7) virus in 2 of 4 seals examined....

  1. Hooded mergansers swim in the waters of KSC

    Science.gov (United States)

    1999-01-01

    A male and two female hooded mergansers swim in the waters of the Merritt Island National Wildlife Refuge at Kennedy Space Center. The male displays its distinctive fan-shaped, black-bordered crest. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000-acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

  2. A female hooded merganser swims in the waters of KSC

    Science.gov (United States)

    1999-01-01

    A female hooded merganser swims solo in the waters of the Merritt Island National Wildlife Refuge at Kennedy Space Center. The male is distinguished by a fan-shaped, black-bordered crest and striped breast. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000-acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

  3. A male hooded merganser swims in the waters of KSC

    Science.gov (United States)

    1999-01-01

    The distinctive fan-shaped, black-bordered crest and striped breast identify this hooded merganser, swimming in the waters of the Merritt Island National Wildlife Refuge at Kennedy Space Center. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000-acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

  4. A merganser swims in the waters of KSC

    Science.gov (United States)

    1999-01-01

    A young female red-breasted merganser swims in the quicksilver water of the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000- acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

  5. Acute Otitis due to Vibrio fluvialis after Swimming

    Directory of Open Access Journals (Sweden)

    Ping-Jen Chen

    2012-01-01

    Full Text Available A 40-year-old female presented with purulent exudate through the left auditive duct and pain in the left ear region, which intensified during mastication. After collection of the pus from the left ear lesion, amoxicillin-clavulanic acid for seven days was prescribed for a presumed diagnosis of acute otitis. Four days later, the pus culture grew V. fluvialis which is further identified by API 20E identification system (bioMérieux. Following the successful completion of a course of antibiotics, the patient recovered completely and without complication. To the best of our knowledge, this is the first case of Vibrio fluvialis otitis after swimming in an immunocompetent patient.

  6. Role of overexpressed CFA/I fimbriae in bacterial swimming.

    Science.gov (United States)

    Cao, Ling; Suo, Zhiyong; Lim, Timothy; Jun, Sangmu; Deliorman, Muhammedin; Riccardi, Carol; Kellerman, Laura; Avci, Recep; Yang, Xinghong

    2012-06-01

    Enterotoxigenic Escherichia coli CFA/I is a protective antigen and has been overexpressed in bacterial vectors, such as Salmonella Typhimurium H683, to generate vaccines. Effects that overexpressed CFA/I may engender on the bacterial host remain largely unexplored. To investigate, we constructed a high CFA/I expression strain, H683-pC2, and compared it to a low CFA/I expression strain, H683-pC, and to a non-CFA/I expression strain, H683-pY. The results showed that H683-pC2 was less able to migrate into semisolid agar (0.35%) than either H683-pC or H683-pY. Bacteria that migrated showed motility halo sizes of H683-pC2 CFA/I fimbriae on bacterial swimming motility.

  7. Drag force and jet propulsion investigation of a swimming squid

    Directory of Open Access Journals (Sweden)

    Tabatabaei Mahdi

    2015-01-01

    Full Text Available In this study, CAD model of a squid was obtained by taking computer tomography images of a real squid. The model later placed into a computational domain to calculate drag force and performance of jet propulsion. The drag study was performed on the CAD model so that drag force subjected to real squid was revealed at squid’s different swimming speeds and comparison has been made with other underwater creatures (e.g., a dolphin, sea lion and penguin. The drag coefficient (referenced to total wetted surface area of squid is 0.0042 at Reynolds number 1.6x106 that is a %4.5 difference from Gentoo penguin. Besides, jet flow of squid was simulated to observe the flow region generated in the 2D domain utilizing dynamic mesh method to mimic the movement of squid’s mantle cavity.

  8. Gamma spectrum measurement in a swimming-pool-type reactor

    International Nuclear Information System (INIS)

    Pla, E.

    1969-01-01

    After recalling the various modes of interaction of gamma rays with matter, the authors describe the design of a spectrometer for gamma energies of between 0.3 and 10 MeV. This spectrometer makes use of the Compton and pair-production effects without eliminating them. The collimator, the crystals and the electronics have been studied in detail and are described in their final form. The problem of calibrating the apparatus is then considered ; numerous graphs are given. The sensitivity of the spectrometer for different energies is determined mainly for the 'Compton effect' group. Finally, in the last part of the report, are given results of an experimental measurement of the gamma spectrum of a swimming-pool type reactor with new elements. (author) [fr

  9. Decontamination of outdoor school swimming pools in Fukushima

    International Nuclear Information System (INIS)

    Saegusa, Jun

    2013-01-01

    After the Fukushima Daiichi NPP accident following the Great East Japan Earthquake, many school swimming pools in Fukushima have suspended water discharge, due to concerns that pool water which contains radioactive fallout is discharged into a river or waterway for agricultural use. The Japan Atomic Energy Agency conducted researches and examinations on the existing absorbent method and the flocculation method as ways for decontaminating pool water. By reviewing and improving these methods through decontamination demonstrations at eight pools in Fukushima, a practical decontamination method for outdoor pools has been established. This report summarizes the methods and results of the decontamination demonstrations carried out at the schools. Also, the surface density of fallout estimated at one of the pools is also presented and discussed in connection with the overall collection ratio of radiocesium at the pool. (author)

  10. Sex differences in elite swimming with advanced age are less than marathon running.

    Science.gov (United States)

    Senefeld, J; Joyner, M J; Stevens, A; Hunter, S K

    2016-01-01

    The sex difference in marathon performance increases with finishing place and age of the runner but whether this occurs among swimmers is unknown. The purpose was to compare sex differences in swimming velocity across world record place (1st-10th), age group (25-89 years), and event distance. We also compared sex differences between freestyle swimming and marathon running. The world's top 10 swimming times of both sexes for World Championship freestyle stroke, backstroke, breaststroke, and butterfly events and the world's top 10 marathon times in 5-year age groups were obtained. Men were faster than women for freestyle (12.4 ± 4.2%), backstroke (12.8 ± 3.0%), and breaststroke (14.5 ± 3.2%), with the greatest sex differences for butterfly (16.7 ± 5.5%). The sex difference in swimming velocity increased across world record place for freestyle (P swimming (P swimming increased with world record place and age, but was less than for marathon running. Collectively, these results suggest more depth in women's swimming than marathon running. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Analysis of the swimming velocity of cadmium-stressed Daphnia magna

    International Nuclear Information System (INIS)

    Baillieul, M.; Blust, R.

    1999-01-01

    The swimming velocity of the waterflea Daphnia magna is dependent on its body size. Therefore, environmental factors like toxic stress that influence growth also influence swimming velocity. An experiment was set up to test whether exposure to cadmium would reduce only growth, with a concomitant decrease in velocity, or whether it would reduce velocity below the swimming velocity of similarly-sized control animals. Daphnids were exposed for 10 days to free cadmium ion concentrations ranging from 1x10 -8 to 1x10 -7 M Cd 2+ , and body size and swimming velocity were measured every 2 days. The results showed that cadmium decreased both growth and velocity, i.e. exposed daphnids swam slower than similarly-sized control daphnids. Swimming velocity provided no indication of successful acclimation in any cadmium treatment. Food consumption and assimilation were reduced by exposure to cadmium. This reduced food intake may have, at least partially, caused the decreased growth rates. However, since reduced food intake does not affect swimming velocity, the reduced swimming velocity must be attributed to toxic effects of cadmium, other than those on food intake. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  12. Effects of Swimming and Cycling Exercise Intervention on Vascular Function in Patients With Osteoarthritis.

    Science.gov (United States)

    Alkatan, Mohammed; Machin, Daniel R; Baker, Jeffrey R; Akkari, Amanda S; Park, Wonil; Tanaka, Hirofumi

    2016-01-01

    Swimming exercise is an ideal and excellent form of exercise for patients with osteoarthritis (OA). However, there is no scientific evidence that regular swimming reduces vascular dysfunction and inflammation and elicits similar benefits compared with land-based exercises such as cycling in terms of reducing vascular dysfunction and inflammation in patients with OA. Forty-eight middle-aged and older patients with OA were randomly assigned to swimming or cycling training groups. Cycling training was included as a non-weight-bearing land-based comparison group. After 12 weeks of supervised exercise training, central arterial stiffness, as determined by carotid-femoral pulse wave velocity, and carotid artery stiffness, through simultaneous ultrasound and applanation tonometry, decreased significantly after both swimming and cycling training. Vascular endothelial function, as determined by brachial flow-mediated dilation, increased significantly after swimming but not after cycling training. Both swimming and cycling interventions reduced interleukin-6 levels, whereas no changes were observed in other inflammatory markers. In conclusion, these results indicate that regular swimming exercise can exert similar or even superior effects on vascular function and inflammatory markers compared with land-based cycling exercise in patients with OA who often has an increased risk of developing cardiovascular disease. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Improved Function and Reduced Pain after Swimming and Cycling Training in Patients with Osteoarthritis.

    Science.gov (United States)

    Alkatan, Mohammed; Baker, Jeffrey R; Machin, Daniel R; Park, Wonil; Akkari, Amanda S; Pasha, Evan P; Tanaka, Hirofumi

    2016-03-01

    Arthritis and its associated joint pain act as significant barriers for adults attempting to perform land-based physical activity. Swimming can be an ideal form of exercise for patients with arthritis. Yet there is no information on the efficacy of regular swimming exercise involving patients with arthritis. The effect of a swimming exercise intervention on joint pain, stiffness, and physical function was evaluated in patients with osteoarthritis (OA). Using a randomized study design, 48 sedentary middle-aged and older adults with OA underwent 3 months of either swimming or cycling exercise training. Supervised exercise training was performed for 45 min/day, 3 days/week at 60-70% heart rate reserve for 12 weeks. The Western Ontario and McMaster Universities Arthritis Index was used to measure joint pain, stiffness, and physical limitation. After the exercise interventions, there were significant reductions in joint pain, stiffness, and physical limitation accompanied by increases in quality of life in both groups (all p swimming and cycling training. Regular swimming exercise reduced joint pain and stiffness associated with OA and improved muscle strength and functional capacity in middle-aged and older adults with OA. Additionally, the benefits of swimming exercise were similar to the more frequently prescribed land-based cycling training. clinicaltrials.gov NCT01836380.

  14. Seasonality in swimming and cycling: Exploring a limitation of accelerometer based studies

    Directory of Open Access Journals (Sweden)

    Flo Harrison

    2017-09-01

    Full Text Available Accelerometer-based studies of children's physical activity have reported seasonal patterns in activity levels. However, the inability of many accelerometers to detect activity while the wearer is swimming or cycling may introduce a bias to the estimation of seasonality if participation in these activities are themselves seasonally patterned. We explore seasonal patterns in children's swimming and cycling among a sample of 7–8 year olds (N = 591 participating in the Millennium Cohort Study, UK. Participating children wore an accelerometer for one week on up to five occasions over the year and their parents completed a diary recording daily minutes spent swimming and cycling. Both swimming and cycling participation showed seasonal patterns, with 2.7 (SE 0.8 more minutes swimming and 5.7 (0.7 more minutes cycling performed in summer compared to winter. Adding swimming and cycling time to accelerometer-determined MVPA increased the summer-winter difference in MVPA from 16.6 (1.6 to 24.9 min. The seasonal trend in swimming and cycling appears to follow the same pattern as accelerometer-measured MVPA. Studies relying solely on accelerometers may therefore underestimate seasonal differences in children's activity.

  15. Feeding of swimming Paramecium with fore-aft asymmetry in viscous fluid

    Science.gov (United States)

    Zhang, Peng; Jana, Saikat; Giarra, Matthew; Vlachos, Pavlos; Jung, Sunghwan

    2013-11-01

    Swimming behaviours and feeding efficiencies of Paramecium Multimicronucleatum with fore-aft asymmetric body shapes are studied experimentally and numerically. Among various possible swimming ways, ciliates typically exhibit only one preferred swimming directions in favorable conditions. Ciliates, like Paramecia, with fore-aft asymmetric shapes preferably swim towards the slender anterior while feeding fluid to the oral groove located at the center of the body. Since both feeding and swimming efficiencies are influenced by fluid motions around the body, it is important to reveal the fluid mechanics around a moving object. Experimentally, μ-PIV methods are employed to characterize the source-dipole streamline patterns and fluid motions around Paramecium. Numerical simulations by boundary element methods are also used to evaluate surface stresses and velocities, which give insights into the efficiencies of swimming and feeding depending on body asymmetry. It is concluded that a slender anterior and fat posterior increases the combined efficiency of swimming and feeding, which matches well with actual shapes of Paramecium. Discrepancies between experiments and simulations are also discussed.

  16. EFFICIENCY OF DIFFERENT METHODOLOGICAL MODELS OF SWIMMING PRACTICE WITH PRE-SCHOOL CHILDREN

    Directory of Open Access Journals (Sweden)

    Dragan Krivokapić

    2006-06-01

    Full Text Available On the sample of 68 preschool boys and girls aged five to six years two models of swimming teaching realised with purpose to research their efficacity. lt was finded before that they were nonswimers. Testers deviated in two similar groups by basic motor and cognitive abilities. First model of swim teaching, signed as time deviated learning, was realised at the cloused swimming pool with 36 testers which exercised twice of week during three months. Second model of swim teaching, signed as time concentrated learning, was realised as a two-week course with 32 testers which exercised at the sea side. Two control assessment of swimming level knowledge were made during experimental process, and a final assesment was made at the and of the experiment Scaling tehnicque was used for assesing. An analysis of the obtained data resulted in the following conclusions: the both models of swim teaching were efficacity and majority of children accepted swim knovvledge. Results of time concentrated model learning were statistical significance beter then time deviated learning only in the control assesments, but the svviming level knowledge was not different in the final assment. That conclusion shows that model of time concentrated learning has more efficacity in the begining, and model of time deviated learning in the later period of teaching

  17. Morphological correlates of swimming activity in wild largemouth bass (Micropterus salmoides) in their natural environment.

    Science.gov (United States)

    Hanson, K C; Hasler, C T; Suski, C D; Cooke, S J

    2007-12-01

    Individual variation in morphology has been linked to organismal performance in numerous taxa. Recently, the relationship between functional morphology and swimming performance in teleost fishes has been studied in laboratory experiments. In this study, we evaluate the relationship between morphology and swimming activity of wild largemouth bass (Micropterus salmoides) during the reproductive period, providing the first data derived on free-swimming fish not exposed to forced swim trials in the laboratory. Sixteen male largemouth bass were angled from their nests, telemetered, and subsequently monitored by a whole-lake acoustic hydrophone array with sub-meter accuracy. Additionally, eleven morphological measurements were taken from digital images of each fish. A principal components analysis of the morphological measurements described 79.8% of the variance. PC1 was characterized by measures of overall body stoutness, PC2 was characterized by measures of the length and depth of the caudal region, and PC3 characterized individuals with relatively large anterior portions of the body and relatively small caudal areas. Of these variables, only PC3 showed significant relationships to swimming activity throughout the parental care period. PC3 was negatively correlated with multiple measures of swimming activity across the parental care period. Furthermore, swimming performance of individual male bass was noted to be repeatable across the parental care period indicating that this phenomenon extends beyond the laboratory.

  18. Plasma renin activity, aldosterone and catecholamine levels when swimming and running.

    Science.gov (United States)

    Guezennec, C Y; Defer, G; Cazorla, G; Sabathier, C; Lhoste, F

    1986-01-01

    The purpose of this study was to determine the response of plasma renin activity (PRA), plasma aldosterone concentration (PAC) and catecholamines to two graded exercises differing by posture. Seven male subjects (19-25 years) performed successively a running rest on a treadmill and a swimming test in a 50-m swimming pool. Each exercise was increased in severity in 5-min steps with intervals of 1 min. Oxygen consumption, heart rate and blood lactate, measured every 5 min, showed a similar progression in energy expenditure until exhaustion, but there was a shorter time to exhaustion in the last step of the running test. PRA, PAC and catecholamines were increased after both types of exercise. The PRA increase was higher after the running test (20.9 ng AngI X ml-1 X h-1) than after swimming (8.66 ng AngI X ml-1 X h-1). The PAC increase was slightly greater after running (123 pg X ml-1) than swimming (102 pg X ml-1), buth the difference was not significant. Plasma catecholamine was higher after the swimming test. These results suggest that the volume shift induced by the supine position and water pressure during swimming decreased the PRA response. The association after swimming compared to running of a decreased PRA and an enhanced catecholamine response rule out a strict dependence of renin release under the effect of plasma catecholamines and is evidence of the major role of neural pathways for renin secretion during physical exercise.

  19. ENERGY SAVING AT OPERATION OF OUTDOOR SWIMMING POOLS

    Directory of Open Access Journals (Sweden)

    V. F. Ivin

    2013-09-01

    Full Text Available Purpose. Energy saving is a major problem in modern power engineering and various energy-consuming devices. They include outdoor swimming pools. In order to maintain them in working condition, especially in winter period, it takes significant amount of thermal energy. Task of heat loss substantial decrease in open swimming pools is considered in the article (on DNURT example. Methodology. The method of determining the mass and heat loss on the basis of criteria equations of heat and mass transfer theory is used. Findings. Calculations of the actual DNURT pool heat loss for different seasons, as for natural convection both for air forced motion above the free water surface are performed. It is shown that for the adiabatic evaporation conditions of water from the pool in winter during blow-off with wind the heat loss can be up to 2 kW/m2 on surface. To reduce these losses it is offered to cover water surface in a pool with a special material with low thermal conductivity on the basis of porous polyethylene during the time when the pool is not used for other purposes. It is shown that the implementation of these standards will reduce the actual heat loss, at least 5-6 times. Originality. The solution of important environmental and energy problem thanks to reducing heat losses by the pool in different times of a year and correspondingly lower emissions of power generating enterprises. Practical value. It is shown that the coating surface of the pool with poorly heat-conducting and easy to install coating will let, at a minimum, to reduce the actual heat loss on 5-6 times and reduce the emissions of power plants generating energy for pool heating.

  20. Factors influencing behavior in the forced swim test

    Science.gov (United States)

    Bogdanova, Olena V.; Kanekar, Shami; D’Anci, Kristen E.; Renshaw, Perry F.

    2017-01-01

    The forced swim test (FST) is a behavioral test in rodents which was developed in 1978 by Porsolt and colleagues as a model for predicting the clinical efficacy of antidepressant drugs. A modified version of the FST added the classification of active behaviors into swimming and climbing, in order to facilitate the differentiation between serotonergic and noradrenergic classes of antidepressant drugs. The FST is now widely used in basic research and the pharmaceutical screening of potential antidepressant treatments. It is also one of the most commonly used tests to assess depressive-like behavior in animal models. Despite the simplicity and sensitivity of the FST procedure, important differences even in baseline immobility rates have been reported between different groups, which complicate the comparison of results across studies. In spite of several methodological papers and reviews published on the FST, the need still exists for clarification of factors which can influence the procedure. While most recent reviews have focused on antidepressant effects observed with the FST, this one considers the methodological aspects of the procedure, aiming to summarize issues beyond antidepressant action in the FST. The previously published literature is analyzed for factors which are known to influence animal behavior in the FST. These include biological factors, such as strain, age, body weight, gender and individual differences between animals; influence of preconditioning before the FST: handling, social isolation or enriched environment, food manipulations, various kinds of stress, endocrine manipulations and surgery; schedule and routes of treatment, dosage and type of the drugs as well as experimental design and laboratory environmental effects. Consideration of these factors in planning experiments may result in more consistent FST results. PMID:23685235