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Sample records for swimming pool disinfectants

  1. 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.

  2. 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

  3. Secondary formation of disinfection by-products by UV treatment of swimming pool water

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Hansen, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2015-01-01

    be replicated by performing the DBP formation assay with higher chlorine concentrations to simulate extended chlorination. Post-UV chlorination of water from a swimming pool that continuously uses UV treatment to control combined chlorine could not induce secondary formation for most DBPs. Concurrence...... trihalomethane formation by UV may be a result of kinetic increase in formation by UV. However, this does not imply that higher trihalomethane concentrations would occur in pools that apply continuous UV treatment. The bromine fraction of halogens in formed trihalomethanes increased with UV dose. This indicates......Formation of disinfection by-products (DBPs) during experimental UV treatment of pool water has previously been reported with little concurrence between laboratory studies, field studies and research groups. In the current study, changes in concentration of seven out of eleven investigated volatile...

  4. Destruction of disinfection byproducts and their precursors in swimming pool water by combined UV treatment and ozonation

    OpenAIRE

    Cheema, Waqas Akram; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2016-01-01

    Both UV treatment and ozonation are used to reduce different types of disinfection byproducts (DBP) in swimming pools. UV treatment is most common as it is particularly efficient in removing the repulsive chlorine like smelling chloramines (combined chlorine). UV treatment of a pool water increased chlorine reactivity and formation of chlor-organic DBP such as trihalomethanes. Based on the similar selective reactivity of ozone and chlorine we hypothesized that the created reactivity towards c...

  5. Secondary formation of disinfection by-products by UV treatment of swimming pool water.

    Science.gov (United States)

    Spiliotopoulou, Aikaterini; Hansen, Kamilla M S; Andersen, Henrik R

    2015-07-01

    Formation of disinfection by-products (DBPs) during experimental UV treatment of pool water has previously been reported with little concurrence between laboratory studies, field studies and research groups. In the current study, changes in concentration of seven out of eleven investigated volatile DBPs were observed in experiments using medium pressure UV treatment, with and without chlorine and after post-UV chlorination. Results showed that post-UV chlorine consumption increased, dose-dependently, with UV treatment dose. A clear absence of trihalomethane formation by UV and UV with chlorine was observed, while small yet statistically significant increases in dichloroacetonitrile and dichloropropanone concentrations were detected. Results indicate that post-UV chlorination clearly induced secondary formation of several DBPs. However, the formation of total trihalomethanes was no greater than what could be replicated by performing the DBP formation assay with higher chlorine concentrations to simulate extended chlorination. Post-UV chlorination of water from a swimming pool that continuously uses UV treatment to control combined chlorine could not induce secondary formation for most DBPs. Concurrence for induction of trihalomethanes was identified between post-UV chlorination treatments and simulated extended chlorination time treatment. Trihalomethanes could not be induced by UV treatment of water from a continuously UV treated pool. This indicates that literature reports of experimentally induced trihalomethane formation by UV may be a result of kinetic increase in formation by UV. However, this does not imply that higher trihalomethane concentrations would occur in pools that apply continuous UV treatment. The bromine fraction of halogens in formed trihalomethanes increased with UV dose. This indicates that UV removes bromine atoms from larger molecules that participate in trihalomethane production during post-UV chlorination. Additionally, no significant

  6. Secondary formation of disinfection by-products by UV treatment of swimming pool water

    International Nuclear Information System (INIS)

    Spiliotopoulou, Aikaterini; Hansen, Kamilla M.S.; Andersen, Henrik R.

    2015-01-01

    Formation of disinfection by-products (DBPs) during experimental UV treatment of pool water has previously been reported with little concurrence between laboratory studies, field studies and research groups. In the current study, changes in concentration of seven out of eleven investigated volatile DBPs were observed in experiments using medium pressure UV treatment, with and without chlorine and after post-UV chlorination. Results showed that post-UV chlorine consumption increased, dose-dependently, with UV treatment dose. A clear absence of trihalomethane formation by UV and UV with chlorine was observed, while small yet statistically significant increases in dichloroacetonitrile and dichloropropanone concentrations were detected. Results indicate that post-UV chlorination clearly induced secondary formation of several DBPs. However, the formation of total trihalomethanes was no greater than what could be replicated by performing the DBP formation assay with higher chlorine concentrations to simulate extended chlorination. Post-UV chlorination of water from a swimming pool that continuously uses UV treatment to control combined chlorine could not induce secondary formation for most DBPs. Concurrence for induction of trihalomethanes was identified between post-UV chlorination treatments and simulated extended chlorination time treatment. Trihalomethanes could not be induced by UV treatment of water from a continuously UV treated pool. This indicates that literature reports of experimentally induced trihalomethane formation by UV may be a result of kinetic increase in formation by UV. However, this does not imply that higher trihalomethane concentrations would occur in pools that apply continuous UV treatment. The bromine fraction of halogens in formed trihalomethanes increased with UV dose. This indicates that UV removes bromine atoms from larger molecules that participate in trihalomethane production during post-UV chlorination. Additionally, no significant

  7. Effect of ozonation of swimming pool water on formation of volatile disinfection by-products - A laboratory study

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Spiliotopoulou, Aikaterini; Cheema, Waqas Akram

    2016-01-01

    dosage, however this decreased with subsequent treatments. For tap and polluted pool water, ozone reacted directly with the pollutants resulting in a short ozone half-life, removing reactivity towards chlorine oxidation and preventing TTHM production. Conversely for pool water samples, due to the long......) was observed to increase in pool water with ozone treatment. Thus, ozonation dosage regimes should be designed such that ozone mostly oxidizes fresh pollutants before chlorine is able to react with it.......Ozonation experiments were performed using unchlorinated tap water used for filling municipal swimming pools, actual pool water and pool water polluted by addition of fresh tap water and artificial body fluid to evaluate ozone kinetics and water quality effects on formation of volatile disinfection...

  8. Destruction of disinfection byproducts and their precursors in swimming pool water by combined UV treatment and ozonation

    DEFF Research Database (Denmark)

    Cheema, Waqas Akram; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    Both UV treatment and ozonation are used to reduce different types of disinfection byproducts (DBP) in swimming pools. UV treatment is most common as it is particularly efficient in removing the repulsive chlorine like smelling chloramines (combined chlorine). UV treatment of a pool water increased...... chlorine reactivity and formation of chlor-organic DBP such as trihalomethanes. Based on the similar selective reactivity of ozone and chlorine we hypothesized that the created reactivity towards chlorine by UV treatment of dissolved organic matter in pool water might also be expressed as an increased...... reactivity towards ozone and that ozonation might saturate the chlorine reactivity created by UV treatment and mitigate the increased DBP formation. By experimentally treating pool water samples, we found that UV treatment makes pool water highly reactive to ozone. The created reactivity towards chlorine...

  9. 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 ...

  10. Prevalence of Ocular, Respiratory and Cutaneous Symptoms in Indoor Swimming Pool Workers and Exposure to Disinfection By-Products (DBPs

    Directory of Open Access Journals (Sweden)

    Guglielmina Fantuzzi

    2010-03-01

    Full Text Available The objective of this cross-sectional study was to investigate the prevalence of self-reported respiratory, ocular and cutaneous symptoms in subjects working at indoor swimming pools and to assess the relationship between frequency of declared symptoms and occupational exposure to disinfection by-products (DBPs. Twenty indoor swimming pools in the Emilia Romagna region of Italy were included in the study. Information about the health status of 133 employees was collected using a self-administered questionnaire. Subjects working at swimming pools claimed to frequently experience the following symptoms: cold (65.4%, sneezing (52.6%, red eyes (48.9% and itchy eyes (44.4%. Only 7.5% claimed to suffer from asthma. Red eyes, runny nose, voice loss and cold symptoms were declared more frequently by pool attendants (lifeguards and trainers when compared with employees working in other areas of the facility (office, cafe, etc.. Pool attendants experienced generally more verrucas, mycosis, eczema and rash than others workers; however, only the difference in the frequency of self-declared mycosis was statistically significant (p = 0.010. Exposure to DBPs was evaluated using both environmental and biological monitoring. Trihalomethanes (THMs, the main DBPs, were evaluated in alveolar air samples collected from subjects. Swimming pool workers experienced different THM exposure levels: lifeguards and trainers showed the highest mean values of THMs in alveolar air samples (28.5 ± 20.2 µg/m3, while subjects working in cafe areas (17.6 ± 12.1 µg/m3, offices (14.4 ± 12.0 µg/m3 and engine rooms (13.6 ± 4.4 µg/m3 showed lower exposure levels. Employees with THM alveolar air values higher than 21 µg/m3 (median value experienced higher risks for red eyes (OR 6.2; 95% CI 2.6–14.9, itchy eyes (OR 3.5; 95% CI 1.5–8.0, dyspnea/asthma (OR 5.1; 95% CI 1.0–27.2 and blocked nose (OR 2.2; 95% CI 1.0–4.7 than subjects with less exposure. This study confirms

  11. 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

    could be replicated by performing the DBP formation assay with higher chlorine concentrations to simulate extended chlorination. Post-UV chlorination of water from a swimming pool that continuously uses UV treatment to control combined chlorine could not induce secondary formation of DBPs....... The trihalomethane induction might result from a kinetic increase in formation by UV. However, this does not imply that higher trihalomethane concentrations would occur in pools that apply continuous UV treatment. The bromine fraction of the halogens in the formed trihalomethanes increased with UV dose, which......-UV chlorine consumption increased, dose-dependently, with UV treatment dose. A clear absence of trihalomethane formation by UV and UV with chlorine was observed. The post-UV chlorination clearly induced formation of DBPs; however, for the total trihalomethanes (TTHM), the inductions were not more than what...

  12. [Environmental surveillance of a sample of indoor swimming pools from Emilia Romagna region: microclimate characteristics and chemical parameters, particularly disinfection by products, in pool waters].

    Science.gov (United States)

    Fantuzzi, G; Righi, E; Predieri, G; Giacobazzi, P; Mastroianni, K; Aggazzotti, G

    2010-01-01

    The aim of the present study was to investigate the environmental and healthy aspects from a representative sample of indoor swimming pools located in the Emilia Romagna region. During the sampling sessions, the occupational environment was evaluated in terms of microclimate parameters and thermal comfort/discomfort conditions. Moreover the chemical risk was assessed by analyzing from the pool water the presence of disinfection by-products (DBPs), such as: trihalomethanes (THMs), haloacetic acids (HAAs), chlorite, chlorate and bromate. The analytical results are in agreement with the Italian legislation (Accordo Stato-Regioni; 2003) even if in some of the sampled indoor swimming pools, the dosed combined chlorine levels, were greater than the Italian limit. With the regard to the microclimate conditions evaluation, the considered thermal indices, Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD%), described a satisfactory occupational environment. Among DBPs, the THMs mean levels (41.4 +/- 30.0 microg/l) resulted close to the values of the current Italian drinking water legislation, and seem to not represent an health issue. The pool waters chlorate levels (range: 5 - 19537 microg/l) need further investigations as recent epidemiological studies on drinking water hypothesized a potential genotoxicity effect of these compounds which are involved in cellular oxidative processes.

  13. Concentrations of disinfection by-products in swimming pool following modifications of the water treatment process: An exploratory study.

    Science.gov (United States)

    Tardif, Robert; Rodriguez, Manuel; Catto, Cyril; Charest-Tardif, Ginette; Simard, Sabrina

    2017-08-01

    The formation and concentration of disinfection by-products (DBPs) in pool water and the ambient air vary according to the type of water treatment process used. This exploratory study was aimed at investigating the short-term impact of modifications of the water treatment process on traditional DBP levels (e.g., trihalomethanes (THMs), chloramines) and emerging DBPs (e.g., Halonitromethanes, Haloketones, NDMA) in swimming pool water and/or air. A sampling program was carried to understand the impact of the following changes made successively to the standard water treatment process: activation of ultraviolet (UV) photoreactor, halt of air stripping with continuation of air extraction from the buffer tank, halt of air stripping and suppression of air extraction from the buffer tank, suppression of the polyaluminium silicate sulfate (PASS) coagulant. UV caused a high increase of Halonitromethanes (8.4 fold), Haloketones (2.1 fold), and THMs in the water (1.7 fold) and, of THMs in the air (1.6 fold) and contributed to reducing the level of chloramines in the air (1.6 fold) and NDMA in the water (2.1 fold). The results highlight the positive impact of air stripping in reducing volatile contaminants. The PASS did not change the presence of DBPs, except for the THMs, which decrease slightly with the use of this coagulant. This study shows that modifications affecting the water treatment process can rapidly produce important and variable impacts on DBP levels in water and air and suggests that implementation of any water treatment process to reduce DBP levels should take into account the specific context of each swimming pool. Copyright © 2017. Published by Elsevier B.V.

  14. 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 ...

  15. 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 ...

  16. Occurrence and Spatial and Temporal Variations of Disinfection By-Products in the Water and Air of Two Indoor Swimming Pools

    Science.gov (United States)

    Catto, Cyril; Sabrina, Simard; Ginette, Charest-Tardif; Manuel, Rodriguez; Robert, Tardif

    2012-01-01

    In order to improve disinfection by-product (DBP) exposure assessment, this study was designed to document both water and air levels of these chemical contaminants in two indoor swimming pools and to analyze their within-day and day-to-day variations in both of them. Intensive sampling was carried out during two one-week campaigns to measure trihalomethanes (THMs) and chloramines (CAMs) in water and air, and haloacetic acids (HAAs) in water several times daily. Water samples were systematically collected at three locations in each pool and air samples were collected at various heights around the pool and in other rooms (e.g., changing room) in the buildings. In addition, the ability of various models to predict air concentrations from water was tested using this database. No clear trends, but actual variations of contamination levels, appeared for both water and air according to the sampling locations and times. Likewise, the available models resulted in realistic but imprecise estimates of air contamination levels from water. This study supports the recommendation that suitable minimal air and water sampling should be carried out in swimming pools to assess exposure to DBPs. PMID:23066383

  17. Effect of medium-pressure UV-lamp treatment on disinfection by-products in chlorinated seawater swimming pool waters.

    Science.gov (United States)

    Cheema, Waqas A; Manasfi, Tarek; Kaarsholm, Kamilla M S; Andersen, Henrik R; Boudenne, Jean-Luc

    2017-12-01

    Several brominated disinfection by-products (DBPs) are formed in chlorinated seawater pools, due to the high concentration of bromide in seawater. UV irradiation is increasingly employed in freshwater pools, because UV treatment photodegrades harmful chloramines. However, in freshwater pools it has been reported that post-UV chlorination promotes the formation of other DBPs. To date, UV-based processes have not been investigated for DBPs in seawater pools. In this study, the effects of UV, followed by chlorination, on the concentration of three groups of DBPs were investigated in laboratory batch experiments using a medium-pressure UV lamp. Chlorine consumption increased following post-UV chlorination, most likely because UV irradiation degraded organic matter in the pool samples to more chlorine-reactive organic matter. Haloacetic acid (HAA) concentrations decreased significantly, due to photo-degradation, but the concentrations of trihalomethanes (THMs) and haloacetonitriles (HANs) increased with post-UV chlorination. Bromine incorporation in HAAs was significantly higher in the control samples chlorinated without UV irradiation but decreased significantly with UV treatment. Bromine incorporation was promoted in THM and HAN after UV and chlorine treatment. Overall, the accumulated bromine incorporation level in DBPs remained essentially unchanged in comparison with the control samples. Toxicity estimates increased with single-dose UV and chlorination, mainly due to increased HAN concentrations. However, brominated HANs are known in the literature to degrade following further UV treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Strategies for chemically healthy public swimming pools

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht

    Swimming pools are used around the world for recreational, rehabilitation and physical activity and therefore it is imperative that the water and air quality are safe for the health of the bathers. Chlorination is by far the most widely applied method to control pool water quality and to prevent...... 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...

  19. Assessing Water Quality: Staphylococci as Microbial Indicators in Swimming Pools.

    Science.gov (United States)

    Rivera, Jo. Bechaida T.; Adera, Tilahun

    1991-01-01

    This study suggests that staphylococci may be the preferred microbial indicators of swimming pool water quality because these organisms met all criteria for best microbial indicators in terms of amount of recovery, resistance to disinfectants, and risk to bathers using water samples from nine swimming pools in Linn and Benton Counties, Oregon. (30…

  20. Progressive Increase in Disinfection By-products and Mutagenicity from Source to Tap to Swimming Pool and Spa Water: Impact of Human Use

    Science.gov (United States)

    Pools and spas are enjoyed throughout the world for exercise and relaxation. However, there are no previous studies on mutagenicity of disinfected spa (hot tub) waters or comprehensive identification of disinfection byproducts (DBPs) formed in spas. Using 28 water samples from ...

  1. 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....

  2. Swimming pool use and birth defect risk.

    Science.gov (United States)

    Agopian, A J; Lupo, Philip J; Canfield, Mark A; Mitchell, Laura E

    2013-09-01

    Swimming during pregnancy is recommended. However, the use of swimming pools is also associated with infection by water-borne pathogens and exposure to water disinfection byproducts, which are 2 mechanisms that are suspected to increase risk for birth defects. Thus, we evaluated the relationship between maternal swimming pool use during early pregnancy and risk for select birth defects in offspring. Data were evaluated for nonsyndromic cases with 1 of 16 types of birth defects (n = 191-1829) and controls (n = 6826) from the National Birth Defects Prevention Study delivered during 2000-2006. Logistic regression analyses were conducted separately for each birth defect type. Separate analyses were conducted to assess any pool use (yes vs no) and frequent use (5 or more occasions in 1 month) during the month before pregnancy through the third month of pregnancy. There was no significant positive association between any or frequent pool use and any of the types of birth defects, even after adjustment for several potential confounders (maternal race/ethnicity, age at delivery, education, body mass index, folic acid use, nulliparity, smoking, annual household income, surveillance center, and season of conception). Frequent pool use was significantly negatively associated with spina bifida (adjusted odds ratio, 0.68; 95% confidence interval, 0.47-0.99). Among offspring of women 20 years old or older, pool use was associated with gastroschisis (adjusted odds ratio, 1.3; 95% confidence interval, 1.0-1.8), although not significantly so. We observed little evidence suggesting teratogenic effects of swimming pool use. Because swimming is a common and suggested form of exercise during pregnancy, these results are reassuring. Copyright © 2013 Mosby, Inc. All rights reserved.

  3. Effect of medium-pressure UV-lamp treatment on disinfection by-products in chlorinated seawater swimming pool waters

    DEFF Research Database (Denmark)

    Cheema, Waqas Akram; Manasfi, Tarek; Kaarsholm, Kamilla Marie Speht

    2017-01-01

    experiments using a medium-pressure UV lamp. Chlorine consumption increased following post-UV chlorination, most likely because UV irradiation degraded organic matter in the pool samples to more chlorine-reactive organic matter. Haloacetic acid (HAA) concentrations decreased significantly, due to photo...

  4. Sanitary Conditions of Public Swimming Pools in Amman, Jordan

    Directory of Open Access Journals (Sweden)

    Ashraf Abu Aqoulah

    2008-09-01

    Full Text Available This study was carried out in the summer of 2005 and investigated all of active public swimming pools (85 out of 93 in Amman, the capital of Jordan. The aim of this study was to find out if these swimming pools are in compliance with Jordanian Standards for Swimming Pools Water (JS 1562/2004. The pools were surveyed against the water microbial quality and other physicochemical parameters indicated in the standards. Two samples from each pool were collected for microbial analysis and pools monitoring were carried out during the afternoon of the weekends when the pools are most heavily used. The results indicated overall poor compliance with the standards. Compliance of the pools water to the microbial parameters was 56.5%, for residual chlorine 49.4%, for pH 87.7%, water temperature 48.8%, and bathing load 70.6%. The results also indicated that water microbial quality deteriorated with time. Multivariate analysis showed significant association of water contamination with time of sample collection, residual chlorine, water temperature and load of swimmers. The poor compliance was attributed to lack of proper disinfection, staff training, proper maintenance, and timely inspection.

  5. 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...

  6. [Chlorine concentrations in the air of indoor swimming pools and their effects on swimming pool workers].

    Science.gov (United States)

    Fernández-Luna, Álvaro; Burillo, Pablo; Felipe, José Luis; Gallardo, Leonor; Tamaral, Francisco Manuel

    2013-01-01

    To describe chlorine levels in the air of indoor swimming pools in Castilla-La Mancha (Spain) and relate them to other chemical parameters in the installation and to the health problems perceived by swimming pool workers. We analyzed 21 pools with chlorine as chemical treatment in Castilla-La Mancha. The iodometry method was applied to measure chlorine concentrations in the air. The concentrations of free and combined chlorine in water, pH and temperature were also evaluated. Health problems were surveyed in 230 swimming pool workers in these facilities. The mean chlorine level in the air of swimming pools was 4.3 ± 2.3mg/m(3). The pH values were within the legal limits. The temperature parameters did not comply with regulations in 17 of the 21 pools analyzed. In the pools where chlorine values in the air were above the legal regulations, a significantly higher percentage of swimming pool workers perceived eye irritation, dryness and irritation of skin, and ear problems. Chlorine values in the air of indoor swimming pools were higher than those reported in similar studies. Most of the facilities (85%) exceeded the concentration of 1.5mg/m(3) established as the limit for the risk of irritating effects. The concentration of chlorine in indoor swimming pool air has a direct effect on the self-perceived health problems of swimming pool workers. Copyright © 2012 SESPAS. Published by Elsevier Espana. All rights reserved.

  7. Virulent Naegleria fowleri in indoor swimming pool.

    Science.gov (United States)

    Kadlec, V; Skvárová, J; Cerva, L; Nebáznivá, D

    1980-01-01

    Naegleria fowleri was isolated from water during a hygienic inspection of a swimming pool in December 1977. This swimming pool was identified as a source of the infectious agent in the years 1962-1965, when a large outbreak of primary amoebic meningoencephalitis (PAME) occurred. First two strains of N. fowleri, pathogenic for white mice after intracerebral and intranasal inoculation, were isolated from water of outlet troughs, additional strains were then isolated from various places; particularly from a cavity in the damaged wall of the pool. The incubation temperature did not inhibit a simultaneous growth of amoebae of the genera Acanthamoeba, Flabellula, Hartmannella and Vahlkampfia in the primocultures. Epidemiological investigations did not reveal any new case of PAME in relation with the occurrence of pathogenic N. fowleri in the swimming pool.

  8. Effect of selection of pH in swimming pool on formation of chlorination by-products

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Willach, Sarah; Mosbæk, Hans

    2011-01-01

    Chlorine is used as disinfection agent in public swimming pools, but also reacts with organic matter in the water forming chlorinat ed disinfection by-products. In order to evaluate the effect of choice of pHsetpoint in the pool we investigated the effect of chlorination of artificial body fluid...

  9. Trihalomethane exposures in indoor swimming pools: a level III fugacity model.

    Science.gov (United States)

    Dyck, Roberta; Sadiq, Rehan; Rodriguez, Manuel J; Simard, Sabrina; Tardif, Robert

    2011-10-15

    The potential for generation of disinfection byproducts (DBPs) in swimming pools is high due to the concentrations of chlorine required to maintain adequate disinfection, and the presence of organics introduced by the swimmers. Health Canada set guidelines for trihalomethanes (THMs) in drinking water; however, no such guideline exists for swimming pool waters. Exposure occurs through ingestion, inhalation and dermal contact in swimming pools. In this research, a multimedia model is developed to evaluate exposure concentrations of THMs in the air and water of an indoor swimming pool. THM water concentration data were obtained from 15 indoor swimming pool facilities in Quebec (Canada). A level III fugacity model is used to estimate inhalation, dermal contact and ingestion exposure doses. The results of the proposed model will be useful to perform a human health risk assessment and develop risk management strategies including developing health-based guidelines for disinfection practices and the design of ventilation system for indoor swimming pools. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. 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...

  11. [Infections transmitted in swimming pools].

    Science.gov (United States)

    von Suzani, C; Hazeghi, P

    1976-01-01

    Public swimmingpools can be the source of infections due to micro-organism such as mycobacterium balnei, adeno and enteroviruses, the virus of plantar warts and molluscum contagiosum, the TRIC-Agent of swimmingpool-conjonctivitis and pathogenic fungi. The transmission of trichomonas vaginalis is considered unlikely-Water of pools, supposed to present satisfactory qualities by standard controls, was found to contain pathogenic staphylococci and pseudomonas aeruginosa. Effective preventive measures include the continuous recording of the redox-potential of the water, limiting the number of visitors to pool design specifications, better desinfection of sanitary installations, regular maintenance of technical equipment including frequent backwashing of filters and exclusion of visitors with communicable disease.

  12. Occurrence and simulation of trihalomethanes in swimming pool water: A simple prediction method based on DOC and mass balance.

    Science.gov (United States)

    Peng, Di; Saravia, Florencia; Abbt-Braun, Gudrun; Horn, Harald

    2016-01-01

    Trihalomethanes (THM) are the most typical disinfection by-products (DBPs) found in public swimming pool water. DBPs are produced when organic and inorganic matter in water reacts with chemical disinfectants. The irregular contribution of substances from pool visitors and long contact time with disinfectant make the forecast of THM in pool water a challenge. In this work occurrence of THM in a public indoor swimming pool was investigated and correlated with the dissolved organic carbon (DOC). Daily sampling of pool water for 26 days showed a positive correlation between DOC and THM with a time delay of about two days, while THM and DOC didn't directly correlate with the number of visitors. Based on the results and mass-balance in the pool water, a simple simulation model for estimating THM concentration in indoor swimming pool water was proposed. Formation of THM from DOC, volatilization into air and elimination by pool water treatment were included in the simulation. Formation ratio of THM gained from laboratory analysis using native pool water and information from field study in an indoor swimming pool reduced the uncertainty of the simulation. The simulation was validated by measurements in the swimming pool for 50 days. The simulated results were in good compliance with measured results. This work provides a useful and simple method for predicting THM concentration and its accumulation trend for long term in indoor swimming pool water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Isolation of Fungi in Swimming pools in Enugu, Nigeria | Mbata ...

    African Journals Online (AJOL)

    Background: It has been established that swimming pools contribute to the spread of fungal infections in susceptible hosts. Objectives: To isolate and identify fungi associated with swimming pools. Methods: A total of 147 samples from water and related areas of each swimming pool were tested for the presence of fungi.

  14. Survey of bacterial contamination of environment of swimming pools in Yazd city, in 2013

    Directory of Open Access Journals (Sweden)

    Hossein Jafari Mansoorian

    2015-09-01

    Full Text Available Background: Infections are readily transmitted as a result of bacterial contamination of swimming pools. Therefore, hygiene and preventing the contamination of swimming pools is of particular importance. The objective of this study was to determine the amount of bacterial contamination in indoor pools of Yazd in 2013. Methods: In this descriptive and analytical study, all indoor swimming pools of Yazd (12 pools were evaluated during the spring and summer of 2013, in terms of bacterial contamination. In order to determine contamination, a sterile cotton swab was used for sampling. On average, 45 samples were taken from different surfaces in each pool (shower, dressing room, sitting places in sauna, platforms and around the pool. In total, about 540 samples from all pools were tested for bacterial contamination. Results: The results show that from 540 samples, bacterial contamination was observed in about 93 samples (17.22%; and was seen more in showers, edges of the pool and jacuzzis, and the slippers used in swimming pools. The most important isolated bacteria types were E. coli, Actinobacteria, Pseudomonas alcaligenes, Pseudomonas aeruginosa and Klebsiella pneumonia. Conclusion: The results indicate the presence of bacterial contamination on the surface of these places. It is recommended that health authorities should pay more attention to cleaning and disinfecting surfaces around the pool, showers, dressing rooms etc, to prevent infectious disease transfer as a result of contact with contaminated swimming pool surfaces.

  15. Photolytic removal of DBPs by medium pressure UV in swimming pool water

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Zortea, R.; Piketty, A.

    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...

  16. Evaluation of Total Coliform, Fecal Coliform and Residual Chlorine in Swimming Pools in Kermanshah on the Season, the type of Pool, Disinfection System and Source of Water Supply in the during of three years (2010-2012

    Directory of Open Access Journals (Sweden)

    K SHarafi

    2014-11-01

    From the results , although the pools of water quality parameters has been studied in almost ideal But in summer, especially on a female pools and pools with wells water supply source than other pools , to be more oversight .

  17. Health effects from swimming training in chlorinated pools and the corresponding metabolic stress pathways.

    Science.gov (United States)

    Li, Jiang-Hua; Wang, Zhi-Hui; Zhu, Xiao-Juan; Deng, Zhao-Hui; Cai, Can-Xin; Qiu, Li-Qiang; Chen, Wei; Lin, Ya-Jun

    2015-01-01

    Chlorination is the most popular method for disinfecting swimming pool water; however, although pathogens are being killed, many toxic compounds, called disinfection by-products (DBPs), are formed. Numerous epidemiological publications have associated the chlorination of pools with dysfunctions of the respiratory system and with some other diseases. However, the findings concerning these associations are not always consistent and have not been confirmed by toxicological studies. Therefore, the health effects from swimming in chlorinated pools and the corresponding stress reactions in organisms are unclear. In this study, we show that although the growth and behaviors of experimental rats were not affected, their health, training effects and metabolic profiles were significantly affected by a 12-week swimming training program in chlorinated water identical to that of public pools. Interestingly, the eyes and skin are the organs that are more directly affected than the lungs by the irritants in chlorinated water; instead of chlorination, training intensity, training frequency and choking on water may be the primary factors for lung damage induced by swimming. Among the five major organs (the heart, liver, spleen, lungs and kidneys), the liver is the most likely target of DBPs. Through metabolomics analysis, the corresponding metabolic stress pathways and a defensive system focusing on taurine were presented, based on which the corresponding countermeasures can be developed for swimming athletes and for others who spend a lot of time in chlorinated swimming pools.

  18. Infections Unlikely to be Spread Through Swimming Pools

    Science.gov (United States)

    ... please visit the Information for Aquatics Professionals page. Pinworm & Swimming Pinworm infections are rarely spread through the use of swimming pools. Pinworm infections occur when a person swallows pinworm eggs ...

  19. Mitigating the impact of swimming pools on domestic water demand

    African Journals Online (AJOL)

    demand. The study shows the need to reduce the impact of swimming pools. This could include: pool covers to reduce evaporation, the recycling of backwash water, the use of rainwater to top up swimming pools, water use surcharges and, finally, appropriate regulation and enforcement to prevent the use of municipal water ...

  20. Particles in swimming pool filters – Does pH determine the DBP formation?

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Willach, Sarah; Mosbæk, Hans

    2012-01-01

    The formation was investigated for different groups of disinfection byproducts (DBPs) during chlorination of filter particles from swimming pools at different pH-values and the toxicity was estimated. Specifically, the formation of the DBP group trihalomethanes (THMs), which is regulated in many...... or initial free chlorine concentrations the particles were chlorinated at different pH-values in the relevant range for swimming pools. THM and HAA formations were reduced by decreasing pH while HAN formation increased with decreasing pH. Based on the organic content the relative DBP formation from...

  1. Automation of water supply and recirculation-filtration of water at a swimming pool using Zelio PLC

    Science.gov (United States)

    Diniş, C. M.; Popa, G. N.; Iagăr, A.

    2018-01-01

    The paper proposes the use of the Zelio PLC for the automation of the water supply and recirculation-filtration system of a swimming pool. To do this, the Zelio SR3B261BD - 24V DC with 10 digital inputs (24V DC) and 10 digital outputs (relay contacts) was used. The proposed application makes the control of the water supply pumps and the water recirculation-filtration from a swimming pool. The recirculation-filtration systems for pools and swimming pools are designed to ensure water cleaning and recirculation to achieve optimum quality and lasting service life. The water filtration process is one of the important steps in water treatment in polls and swimming pools. It consists in recirculation of the entire volume of water and begins by absorbing the water in the pool by means of a pump followed by the passing of water through the filter, disinfectant and pH dosing, and reintroducing the water back into the pool or swimming pool through the discharge holes. Filters must to work 24 hours a day to remove pollutants from pools or swimming pools users. Filtration removes suspension particles with different origins. All newly built pools and swimming pools must be fitted with water recirculation systems, and existing ones will be equipped with water recirculation and water treatment systems.

  2. 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)

  3. Determination of Monochloroacetic Acid in Swimming Pool Water by Ion Chromatography-Conductivity Detection

    Directory of Open Access Journals (Sweden)

    Maria Pythias B. Espino

    2013-02-01

    Full Text Available In this study, an analytical method involving ion chromatography with conductivity detection was developed and optimized for the determination of monochloroacetic acid in swimming pool water. The ion chromatographic method has a detection limit of 0.02 mg L-1 and linear range of 0.05 to 1.0 mg L-1 with correlation coeff icient of 0.9992. The method is reproducible with percent RSD of 0.052% (n=10. The recovery of monochloroacetic acid spiked in different water types (bottled, tap and swimming pool water ranged from 28 to 122%. In dilute solutions, chloride and bromide were simultaneously analyzed along with monochloroacetic acid using the optimized method. Chloride and bromide have detection limits of 0.01 to 0.05 mg L-1, respectively. The usefulness of the ion chromatographic method was demonstrated in the analysis of monochloroacetic acid in swimming pool water samples. In such highly-chlorinated samples, an Ag/H cartridge was used prior to the ion chromatographic determination so as to minimize the signal due to chloride ion. Monochloroacetic acid was detected in concentrations between 0.020 and 0.093 mg L-1 in three of the six swimming pool water samples studied. The presence of monochloroacetic acid in the swimming pool water samples suggests the possible occurrence of other disinfection by-products in these waters.

  4. The Ineffectiveness of Manual Treatment of Swimming Pools | Nnaji ...

    African Journals Online (AJOL)

    The University of Nigeria, Nsukka swimming pool was monitored for a period spanning about three months. The pool was constructed in 1961 and has been in operation since then except that many facilities including the treatment system are no longer functional forcing management to resort to treatment of the pool water ...

  5. An Investigation on Physicochemical and Microbial Water Quality of Swimming Pools in Yazd

    Directory of Open Access Journals (Sweden)

    M Dehvari

    2012-08-01

    Full Text Available Introduction: Disrespect of health regulations and proper disinfection of water and swimming pools is effective in incidence of health problems and transfer of infectious diseases to swimmers. The aim of this research was to investigate water of swimming pools in Yazd city and compare the results with national standards. Methods: In this study, 11 active covered swimming pools of Yazd city were sampled as census. Parameters of temperature, pH, amount of free and Combined chlorine residual, turbidity, alkalinity, hardness, the population of heterotrophic bacteria, Staphylococcus aureus, Pseudomonas aeruginosa, fecal streptococci, and fecal coliforms were studied. Sampling has been conducted every two weaks for 3 months and samples were analyzed under standard procedures. Results: In this research, amount of pH in 84.73%, free residual chlorine in 44.18%, Combined residual chlorine in 72.45%, alkalinity in19.82%, turbidity in 86.36%, hardness in 57.18% and temperature in 13.73% Samples were desirable. The fecal streptococci bacteria was not shown in all the swimming pools and population of heterotrophic bacteria, Staphylococcus aureus, Pseudomonas aeruginosa and fecal coliforms in 56.73%, 93.27%, 79.36% and 91.45% cases were desirable, respectively. Statistical analysis indicated that there is a direct relationship between Water turbidity and population of heterotraphic bacteria. Conclusion: According to the results, the parameters of heterotrophic bacteria population, also the alkalinity and temperature had the least compliant with the standards that shows the necessity for continuous monitoring of physical, chemical and microbial parameters and also control of filtration and disinfection of water condition of swimming pools.

  6. Perceived health problems in swimmers according to the chemical treatment of water in swimming pools.

    Science.gov (United States)

    Fernández-Luna, Álvaro; Burillo, Pablo; Felipe, José Luis; del Corral, Julio; García-Unanue, Jorge; Gallardo, Leonor

    2016-01-01

    The objective of this study was to determine which chemical treatment used for disinfecting water in indoor swimming pools had the least impact on users' perceptions of health problems, and which generated the greatest satisfaction with the quality of the water. A survey on satisfaction and perceived health problems was given to 1001 users at 20 indoor swimming pools which used different water treatment methods [chlorine, bromine, ozone, ultraviolet lamps (UV) and salt electrolysis]. The findings suggest that there is a greater probability of perceived health problems, such as eye and skin irritation, respiratory problems and skin dryness, in swimming pools treated with chlorine than in swimming pools using other chemical treatment methods. Pools treated with bromine have similar, although slightly better, results. Other factors, such as age, gender, time of day of use (morning and afternoon) and type of user (competitive and recreational), can also affect the probability of suffering health problems. For all of the above, using combined treatment methods as ozone and UV, or salt electrolysis produces a lower probability of perceived health problems and greater satisfaction.

  7. Mitigating the impact of swimming pools on domestic water demand ...

    African Journals Online (AJOL)

    South Africa is a water-scarce country where the sustainable provision of water to its citizens is one of the most significant challenges faced. A recent study in Cape Town, South Africa, investigated the impact of residential swimming pools on household water demand and found that, on average, the presence of a swimming ...

  8. How to improve hygienic behaviour in holiday park swimming pools

    NARCIS (Netherlands)

    Stronks, I.; Keuten, M.G.A.

    2016-01-01

    Previous studies on contamination of swimming pool water showed that the hygienic behaviour of swimmers is the most important factor. The suggested hygienic behaviour is; having a pre-swim shower and using the toilet when nature calls. Knowing the importance of hygienic behaviour is one thing,

  9. 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...

  10. Study of Fungal Contamination of Indoor Public Swimming Pools

    OpenAIRE

    H Nanbakhsh; K Diba; K Hazarti

    2004-01-01

    Fungi are found in different environments with variable distribution patterns depending on various factors. The aim of this study was determination of fungal contaminants in public swimming pools in Uromia, Iran. The fungal contaminations of four indoor swimming pools were studied by using membrane filtration and swab sampling method. Samples were collected by a manual plastic pump, in a 200 ml sterilized bottle. All samples were collected within 2 hours and then transferred to the laboratory...

  11. The Ineffectiveness of Manual Treatment of Swimming Pools NNAJI ...

    African Journals Online (AJOL)

    Michael Horsfall

    period, the COD was above 80mg/l, the pH was between 6.2 and 7.1 as against 7.2 to 7.8 recommended by standards. The total plate count was within limits but ... strains of normal human flora have been found in chlorinated swimming pools ... mucus, saliva or skin in the swimming pool water or similar recreational water ...

  12. Study on water evaporation rate from indoor swimming pools

    Science.gov (United States)

    Rzeźnik, Ilona

    2017-11-01

    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.

  13. 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.

  14. [Surveillance of the sanitary conditions of a public swimming pool in the city of Palermo (Italy)].

    Science.gov (United States)

    Maida, Carmelo Massimo; Di Benedetto, Maria Antonella; Firenze, Alberto; Calamusa, Giuseppe; Di Piazza, Florinda; Milici, Maria Eleonora; Romano, Nino

    2008-01-01

    In a previous study we evaluated the microbiological quality of water of seven pools in the city of Palermo through evaluation of bacterial indicators of faecal contamination and of protozoa (Giardia and Cryptosporidium). In this study we also searched for the presence of fungi in two swimming pools of a public swimming facility in the same city. Samples were collected from both pools, their filtration systems and floor surfaces of the facility. Chemical-physical and microbiological examination of water of the two pools have shown that quality of water depends on the concentration of residual free chlorine and on the number of bathers in the pool. The values of four microbiological parameters (bacterial load at 22 degrees C and 36 degrees C, presence of coagulase-negative Staphylococci and Pseudomonas spp.) increased with diminishing chlorine concentrations and with increasing number of pool users. Faecal bacteria, Giardia and Cryptosporidium were not found. On the other hand, various fungi were isolated from floor surfaces and pool water even in the presence of optimal chlorine concentrations. This study confirms the importance of regular maintenance of pool disinfection systems and suggests the need to search for other micro-organisms not included in the current legislation (Giardia, Cryptosporidium and fungi).

  15. 21 CFR 1250.89 - Swimming pools.

    Science.gov (United States)

    2010-04-01

    ... equipped so as to provide complete circulation, replacement, and filtration of the water in the pool every six hours or less. Suitable means of chlorination and, if necessary, other treatment of the water shall be provided to maintain the residual chlorine in the pool water at not less than 0.4 part per...

  16. 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.

  17. Gene expression changes in blood RNA after swimming in a chlorinated pool.

    Science.gov (United States)

    Salas, Lucas A; Font-Ribera, Laia; Bustamante, Mariona; Sumoy, Lauro; Grimalt, Joan O; Bonnin, Sarah; Aguilar, Maria; Mattlin, Heidi; Hummel, Manuela; Ferrer, Anna; Kogevinas, Manolis; Villanueva, Cristina M

    2017-08-01

    Exposure to disinfection by-products (DBP) such as trihalomethanes (THM) in swimming pools has been linked to adverse health effects in humans, but their biological mechanisms are unclear. We evaluated short-term changes in blood gene expression of adult recreational swimmers after swimming in a chlorinated pool. Volunteers swam 40min in an indoor chlorinated pool. Blood samples were drawn and four THM (chloroform, bromodichloromethane, dibromochloromethane and bromoform) were measured in exhaled breath before and after swimming. Intensity of physical activity was measured as metabolic equivalents (METs). Gene expression in whole blood mRNA was evaluated using IlluminaHumanHT-12v3 Expression-BeadChip. Linear mixed models were used to evaluate the relationship between gene expression changes and THM exposure. Thirty-seven before-after pairs were analyzed. The median increase from baseline to after swimming were: 0.7 to 2.3 for MET, and 1.4 to 7.1μg/m 3 for exhaled total THM (sum of the four THM). Exhaled THM increased on average 0.94μg/m 3 per 1 MET. While 1643 probes were differentially expressed post-exposure. Of them, 189 were also associated with exhaled levels of individual/total THM or MET after False Discovery Rate. The observed associations with the exhaled THM were low to moderate (Log-fold change range: -0.17 to 0.15). In conclusion, we identified short-term gene expression changes associated with swimming in a pool that were minor in magnitude and their biological meaning was unspecific. The high collinearity between exhaled THM levels and intensity of physical activity precluded mutually adjusted models with both covariates. These exploratory results should be validated in future studies. Copyright © 2017. Published by Elsevier B.V.

  18. The effect of UV treatment on highly polluted and normal operated swimming pools

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2017-01-01

    Water samples from 2 indoor public swimming pool facilities with significantly different organic matter concentrations in the recirculation were tested to evaluate UV-induced effects on water chemistry. The aim of the study was to investigate the impact of poor water quality due to increased...... organic carbon (TOC) and the potential effect of increased nitrate concentration on disinfection by-product (DBP) formation in pool water. Concentration change on total trihalomethanes (TTHM) was investigated utilising medium pressure UV treatment in conjunction with chlorine. Post-UV chlorine consumption...... increased, UV dose-dependently. The post-UV chlorination clearly induced TTHM formation in both polluted and normal operated pools. However, elevated TOC concentration did not increase significantly the DBP formation. Regarding the brominated fraction of the halogens in the formed TTHMs, it appeared...

  19. 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 ...

  20. Acanthamoeba species in Swimming Pools of Cairo, Egypt.

    Directory of Open Access Journals (Sweden)

    Ahmad Al-Herrawy

    2014-06-01

    Full Text Available The free-living amoebae Acanthamoeba spp. have been recognized as etiologic agents of amoebic encephalitis, keratitis, otitis, lung lesions and other skin infections mainly in immuno-compromised individuals. The purpose of this study is to detect the presence of Acanthamoeba in swimming pools in Egypt using a polymerase chain reaction (PCR method.Water samples were collected from 10 different swimming pools in Cairo, Egypt. Samples were cultured on non-nutrient agar for the detection of Acanthamoeba isolates that were confirmed by PCR amplification using genus specific primers. The molecularly confirmed Acanthamoeba isolates were morphologically identified to the species level.Members of genus Acanthamoeba were detected in 49.2% of the examined swimming-pool water samples. Morphologically, six Acanthamoeba species were isolated from the examined swimming pool water namely A. polyphaga, A.castellanii, A. rhysodes, A. mauritaniensis, A. royreba and A. triangularis. All the identified species of Acanthamoeba were molecularly confirmed to be related to the genus Acanthamoeba.The isolated species of Acanthamoeba could provoke variable degrees of infections to the swimmers. The culture method is cheaper and easier than PCR techniques that are faster for the detection of free-living amoebae.

  1. 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

  2. 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

  3. 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

  4. Combined UV treatment and ozonation for the removal of by-product precursors in swimming pool water

    DEFF Research Database (Denmark)

    Cheema, Waqas Akram; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2017-01-01

    Both UV treatment and ozonation are used to reduce different types of disinfection by-products (DBPs) in swimming pools. UV treatment is the most common approach, as it is particularly efficient at removing combined chlorine. However, the UV treatment of pool water increases chlorine reactivity...... and the formation of chloro-organic DBPs such as trihalomethanes. Based on the similar selective reactivity of ozone and chlorine, we hypothesised that the created reactivity to chlorine, as a result of the UV treatment of dissolved organic matter in swimming pool water, might also be expressed as increased...... reactivity to ozone. Moreover, ozonation might saturate the chlorine reactivity created by UV treatment and mitigate increased formation of a range of volatile DBPs. We found that UV treatment makes pool water highly reactive to ozone. The subsequent reactivity to chlorine decreases with increasing ozone...

  5. 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.

  6. Acute changes in serum immune markers due to swimming in a chlorinated pool.

    Science.gov (United States)

    Vlaanderen, Jelle; van Veldhoven, Karin; Font-Ribera, Laia; Villanueva, Cristina M; Chadeau-Hyam, Marc; Portengen, Lützen; Grimalt, Joan O; Zwiener, Christian; Heederik, Dick; Zhang, Xiangru; Vineis, Paolo; Kogevinas, Manolis; Vermeulen, Roel

    2017-08-01

    Exposure to disinfectants and disinfection byproducts (DBPs) due to swimming in chlorinated water has been associated with allergic and respiratory health effects, including asthma. Biological mechanisms contributing to these associations are largely unknown. We hypothesized a potential pathway involving modulation of the immune system. We assessed levels of immune markers (CCL11, CCL22, CXCL10, CRP, EGF, GCSF, IL-8, IL-17, IL-1RA, MPO, VEGF, Periostin) in serum collected from 30 women and 29 men before and after 40min of swimming in a chlorinated pool. Exposure to DBPs was assessed by measuring bromodichloromethane, bromoform, chloroform, and dibromochloromethane in exhaled breath before and after swimming. Covariate data including information on physical activity was available through questionnaires and measurements. We assessed the association between indicators of swimming in a chlorinated pool and changes in serum immune marker concentrations using linear regression with bivariate normal distributions and adjusted for multiple comparisons by applying the Benjamini-Hochberg procedure. We observed a significant decrease in serum concentrations of IL-8 (-12.53%; q=2.00e-03), CCL22 (-7.28%; q=4.00e-04), CCL11 (-7.15%; q=9.48e-02), CRP (-7.06%; q=4.68e-05), and CXCL10 (-13.03%; q=6.34e-14) and a significant increase in IL-1RA (20.16%; q=4.18e-06) from before to after swimming. Associations with quantitative measurements of DBPs or physical activity were similar in direction and strength. Most of the observed associations became non-significant when we adjusted the effects of exposure to DBPs for physical activity or vice-versa. Our study indicates that swimming in a chlorinated pool induces perturbations of the immune response through acute alterations of patterns of cytokine and chemokine secretion. The observed effects could not be uniquely attributed to either exposure to DBPs or physical activity. Evidence in the literature suggests that observed decreases in

  7. QUALITATIVE ASSESSMENT OF INDOOR SWIMMING POOL AND SEASONAL BATHING RESORTS WATER USING MICROTOX® TEST

    Directory of Open Access Journals (Sweden)

    Edyta Łaskawiec

    2016-12-01

    Full Text Available The tests were to specify the toxic effect on the basis of Vibrio fischeri luminescence inhibition caused by chemical compounds present in pool water samples. The testing tool was Microtox®; This biotest produces quick results thus making it a comfortable tool for testing water for various toxicants. Furthermore, UV254 absorbance measure was carried out and its value was a proxy parameter for defining participation of precursors to disinfection by-products in the samples. Some of the samples had high UV254 values, one of them was 144 m 1. The Microtox® quality tests of indoor and outdoor swimming pool water presented in the paper proved impact of such factors like air exchange or supply of pool water circulation on water quality. Seasonal bathing waters had lower toxicity values. In the context of the work specifies that the impurities in the water cause its toxicity. However, there was no relationship between high UV254 absorbance values and higher toxicity of the samples. The toxicological analysis may serve as a screening test of swimming pool water quality. It is of key importance to check the free chlorine value for a water sample. High chlorine concentration can cause higher bioluminescence inhibition values.

  8. 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.

  9. 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.

  10. 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

  11. Occurrence of pharmaceuticals and UV filters in swimming pools and spas.

    Science.gov (United States)

    Ekowati, Yuli; Buttiglieri, Gianluigi; Ferrero, Giuliana; Valle-Sistac, Jennifer; Diaz-Cruz, M Silvía; Barceló, Damià; Petrovic, Mira; Villagrasa, Marta; Kennedy, Maria D; Rodríguez-Roda, Ignasi

    2016-07-01

    The occurrence of 32 pharmaceuticals and 14 UV filters in swimming pools and spas was studied. Fifty-one water samples were collected from 17 pools located in sport centres and hotels in Catalonia, Spain. The samples were analysed by liquid chromatography-tandem mass spectrometry. The pharmaceuticals atenolol, carbamazepine, hydrochlorothiazide, metronidazole, ofloxacin, sulfamethoxazole, acetaminophen, ibuprofen, ketoprofen and phenazone were measured in water samples at concentrations higher than their limit of quantification (LOQ). The highest concentration of any individual pharmaceutical was measured for the diuretic hydrochlorothiazide (904 ng/L). The most frequently detected pharmaceutical was carbamazepine, as it was observed in more than half of all the water samples measured (53 %, 27/51). The UV filters at concentrations higher than LOQ in water samples were BP1, BP2, BP3, BP8, THB, 4DHB, 4MBC, OD-PABA, 1HBT, MeBT and DMeBT. The highest concentration of UV filter observed was 4MBC (69.3 ng/L) while the most frequent UV filters in the samples were 1HBT (59 %, 30/51). The results also showed that pharmaceuticals and UV filters were most frequently found in spas. Finally, from a water treatment technology perspective, the lowest occurrence of pharmaceuticals was in the pools applying sand filters followed by disinfection by sodium hypochlorite, while the lowest occurrence of UV filters was in the pools applying coagulation, sand filtration, UV and salt electrolysis.

  12. Evaluation of biological and physico-chemical quality of public swimming pools, Hamadan (Iran

    Directory of Open Access Journals (Sweden)

    Edris Hoseinzadeh

    2013-01-01

    Conclusion: As results showed the residual chlorine in pools water was lower than standard level and as regard to microbial contamination in pool water, it can be concluded that the disinfection system has been impaired.

  13. 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…

  14. Abandoning nature: swimming pools and clean, healthy recreation in Hamilton, Ontario, c. 1930s-1950s.

    Science.gov (United States)

    Bouchier, Nancy B; Cruikshank, Ken

    2011-01-01

    Municipal swimming pools arose as a technological fix for an urban public health and recreation crisis in Hamilton when its bay became a polluted sink for residential and industrial wastes. Until World War II, city leaders and medical authorities believed that they could identify, delineate, and construct safe natural swimming areas along the bay's shore, supplemented by a few public artificial swimming pools. After the war, the pollution situation worsened. For those who couldn't travel to cleaner lakeshores elsewhere, local authorities created swimming pools, thus abandoning the natural waters of the bay to the "constructive power of the profit motive".

  15. UV filters interaction in the chlorinated swimming pool, a new challenge for urbanization, a need for community scale investigations.

    Science.gov (United States)

    Sharifan, Hamidreza; Klein, David; Morse, Audra N

    2016-07-01

    Sunscreen products and some personal care products contain the Ultraviolet (UV) chemical filters, which are entering the surface water. Public concerns about secondary effects of these compounds are growing because of the contamination of the aquatic environment that may reach to potentially toxic concentration levels. This article highlights the reaction of certain UV filters with hypochlorite disinfectant in the presence of sunlight. Due to urbanization and industrialization, use of outdoor plastic swimming pools is increasing. The relatively smaller volume of these pools compared to larger pools may increase the concentration of the UV filters in the pool and their potential interactions with materials of human origin (urine, sweat, cosmetics, skin cells, and hair) to the levels of toxicity concerns for children through the creation of disinfection by products (DBP). Based on our analysis, the minimum concentration levels of 2.85, 1.9, 1.78 and 0.95g/L, respectively, for EHMC, OC, 4-MBC and BP3 UV filters in children pools are predicted. Therefore, this article calls for an urgent investigation of potential toxic effects of the UV filters, the creation of DBPs and their subsequent impacts on human health. Published by Elsevier Inc.

  16. Trihalomethanes in Lisbon indoor swimming pools: occurrence, determining factors, and health risk classification.

    Science.gov (United States)

    Silva, Zelinda Isabel; Rebelo, Maria Helena; Silva, Manuela Manso; Alves, Ana Martins; Cabral, Maria da Conceição; Almeida, Ana Cristina; Aguiar, Fátima Rôxo; de Oliveira, Anabela Lopes; Nogueira, Ana Cruz; Pinhal, Hermínia Rodrigues; Aguiar, Pedro Manuel; Cardoso, Ana Sofia

    2012-01-01

    Characterization of water quality from indoor swimming pools, using chorine-based disinfection techniques, was performed during a 6-mo period to study the occurrence, distribution, and concentration factors of trihalomethanes (THM). Several parameters such as levels of water THM, water and air chloroform, water bromodichloromethane (BDCM), water dibromochloromethane (DBCM), water bromoform (BF), free residual chlorine (FrCl), pH, water and air temperature, and permanganate water oxidizability (PWO) were determined in each pool during that period. Chloroform (CF(W)) was the THM detected at higher concentrations in all pools, followed by BDCM, DBCM, and BF detected at 99, 34, and 6% of the samples, respectively. Water THM concentrations ranged from 10.1 to 155 μg/L, with 6.5% of the samples presenting values above 100 μg/L (parametric value established in Portuguese law DL 306/2007). In this study, air chloroform (CF(Air)) concentrations ranged from 45 to 373 μg/m³ with 24% of the samples presenting values above 136 μg/m³ (considered high exposure value). Several significant correlations were observed between total THM and other parameters, namely, CF(W), CF(Air), FrCl, water temperature (T(W)), and PWO. These correlations indicate that FrCl, T(W) and PWO are parameters that influence THM formation. The exposure criterion established for water THM enabled the inclusion of 67% of Lisbon pools in the high exposure group, which reinforces the need for an improvement in pool water quality.

  17. Semi-Automatic Detection of Swimming Pools from Aerial High-Resolution Images and LIDAR Data

    Directory of Open Access Journals (Sweden)

    Borja Rodríguez-Cuenca

    2014-03-01

    Full Text Available Bodies of water, particularly swimming pools, are land covers of high interest. Their maintenance involves energy costs that authorities must take into consideration. In addition, swimming pools are important water sources for firefighting. However, they also provide a habitat for mosquitoes to breed, potentially posing a serious health threat of mosquito-borne disease. This paper presents a novel semi-automatic method of detecting swimming pools in urban environments from aerial images and LIDAR data. A new index for detecting swimming pools is presented (Normalized Difference Swimming Pools Index that is combined with three other decision indices using the Dempster–Shafer theory to determine the locations of swimming pools. The proposed method was tested in an urban area of the city of Alcalá de Henares in Madrid, Spain. The method detected all existing swimming pools in the studied area with an overall accuracy of 99.86%, similar to the results obtained by support vector machines (SVM supervised classification.

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

    Directory of Open Access Journals (Sweden)

    Mančić Marko V.

    2014-01-01

    Full Text Available 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 pool building. The mathematical model of the swimming pool is used with the created multi-zone building model in TRNSYS software to determine pool hall energy demand and pool losses. Energy loss for pool water and pool hall heating and ventilation are analyzed for different target pool water and air temperatures. The simulation showed that pool water heating accounts for around 22%, whereas heating and ventilation of the pool hall for around 60% of the total pool hall heat demand. With a change of preset controller air and water temperatures in simulations, evaporation loss was in the range 46-54% of the total pool losses. A solar thermal sanitary hot water system was modelled and simulated to analyze it's potential for energy savings of the presented demand side model. The simulation showed that up to 87% of water heating demands could be met by the solar thermal system, while avoiding stagnation. [Projekat Ministarstva nauke Republike Srbije, br. III 42006: Research and development of energy and environmentally highly effective polygeneration systems based on using renewable energy sources

  19. Occurrence and human exposure of parabens and their chlorinated derivatives in swimming pools.

    Science.gov (United States)

    Li, Wenhui; Shi, Yali; Gao, Lihong; Liu, Jiemin; Cai, Yaqi

    2015-11-01

    As an emerging group of endocrine-disrupting chemicals, parabens have attracted growing attention due to their potential effects on human health. In the present study, the occurrence and distribution of eight parabens, four chlorinated parabens, and their common hydrolysis product, p-hydroxybenzoic acid (PHBA), were investigated in 39 swimming pools in Beijing, China. Methyl paraben and propyl paraben were the predominant compounds in swimming pools, accounting for 91.2 % of the total parabens. It is noteworthy that octyl paraben, a paraben with longer chain, was firstly detected in this study. There were several factors affecting the levels of parabens among the 39 swimming pools. The concentrations of parabens and chlorinated derivatives detected in indoor pools (144 ng L(-1)) were roughly 20-fold higher than those in outdoor pools (6.78 ng L(-1)). Hotel pools appear to present higher level of target compounds (361 ng L(-1)) than that in health club (228 ng L(-1)), municipal (130 ng L(-1)), school (75.6 ng L(-1)), and community pools (63.0 ng L(-1)). Moreover, the level of these compounds in pools during weekends (174 ng L(-1)) was much higher than that during weekdays (52.3 ng L(-1)). The dynamics of target compounds were also investigated to provide a general trend of the level of parabens in a school indoor swimming pool during a 14-week period. Human exposure assessment was conducted to estimate the potential risk of exposure to parabens and their chlorinated derivatives in swimming pools. Considering the total exposure dose of multiple parabens, human exposure to parabens from the water of swimming pools is negligible. However, the threat of these parabens to children in swimming pool should be concerned.

  20. Effect of pool length on blood lactate, heart rate, and velocity in swimming.

    Science.gov (United States)

    Keskinen, O P; Keskinen, K L; Mero, A A

    2007-05-01

    Exercise testing in water has been used to follow the progression of conditioning during regular training in swimmers. The present study examined the effects of pool length in eleven male swimmers on a set of 5 x 200-m freestyle swims with increasing speed from submaximal to maximal. Mean velocity of swimming, blood lactate and heart rate were examined in both 25-m and 50-m pools. Turning benefit as a marker for turning skill was measured separately by a underwater video system (speed difference between pre- and post-turning) during short all-out swims. Maximum force during swimming was measured in tethered swimming and explosive strength of leg extensor muscles was evaluated by a counter movement jump. The significantly higher (p=0.033 - 0.000) blood lactate values for the 50-m pool as compared to the 25-m pool were found at each point of swimming velocity versus blood lactate curve. The highest post-test lactate level was 7.36 +/- 1.47 mmol x l (-1) in the short course and 8.24 +/- 1.55 mmol x l (-1) (p=0.033) in the long course. The maximum swimming velocity was significantly greater (4.5 %) in the 25-m pool swimming (1.38 +/- 0.11 m x s (-1) vs. 1.32 +/- 0.12 m x s (-1); p=0.000). The heart rate values were significantly (p=0.020 - 0.000) lower in the short course than in the long course at all points of submaximal velocity with a mean difference of 7.3 +/- 0.7 bpm. Heart rate was equal (172 +/- 14 vs. 172 +/- 14 bpm) after the maximum swims in both short and long course. The turning benefit in the short maximum swim was 0.12 +/- 0.05 m x s (-1) (8.1 +/- 3.2 %), correlating positively with the difference in maximal swimming velocity between the short and long-pool swims (r = 0.59; p = 0.029), with the maximum force during tethered swimming (r=0.75; p=0.004) and with the vertical jumping height in the counter movement jump (r=0.55; p=0.039). We conclude that the pool length has a strong effect on blood lactate concentration and heart rate with greater swimming

  1. Titanium distribution in swimming pool water is dominated by dissolved species

    International Nuclear Information System (INIS)

    David Holbrook, R.; Motabar, Donna; Quiñones, Oscar; Stanford, Benjamin; Vanderford, Brett; Moss, Donna

    2013-01-01

    The increased use of titanium dioxide nanoparticles (nano-TiO 2 ) in consumer products such as sunscreen has raised concerns about their possible risk to human and environmental health. In this work, we report the occurrence, size fractionation and behavior of titanium (Ti) in a children's swimming pool. Size-fractionated samples were analyzed for Ti using ICP-MS. Total titanium concentrations ([Ti]) in the pool water ranged between 21 μg/L and 60 μg/L and increased throughout the 101-day sampling period while [Ti] in tap water remained relatively constant. The majority of [Ti] was found in the dissolved phase (<1 kDa), with only a minor fraction of total [Ti] being considered either particulate or microparticulate. Simple models suggest that evaporation may account for the observed variation in [Ti], while sunscreen may be a relevant source of particulate and microparticule Ti. Compared to diet, incidental ingestion of nano-Ti from swimming pool water is minimal. -- Highlights: •Total titanium concentrations in unfiltered swimming pool water ranged between 21 and 60 μg/L. •Evaporation of the swimming pool water is suspected of causing a temporal increase in [Ti]. •The vast majority of Ti is found in the dissolved phase (<1 kD). •Swimming pools are not a significant Ti source for human exposure via ingestion. -- In children's swimming pool water, the majority of titanium is found in the dissolved phase

  2. THE USE OF MEMBRANE TECHNIQUES IN SWIMMING POOL WATER TREATMENT

    Directory of Open Access Journals (Sweden)

    Edyta Łaskawiec

    2017-07-01

    Full Text Available The paper has determined the suitability of membrane processes (UF ultrafiltration, UF, and nanofiltration, NF for the purification of waste streams, so-called backwash water, obtained from washing filtration beds in a swimming pool water system. The backwash water samples were taken from the circuits located in two indoor facilities with a different purpose of the basins. Moreover, the samples were characterized by varying quality, as described by selected physicochemical parameters (such as turbidity and ultraviolet absorbance UV254. Commercial membranes were used for the tests. The transport-separation properties of the membranes were determined based on the volumetric flux of the permeate. In addition, backwash water samples before and after the membrane process were subjected to toxicological assessment using the Microtox® screening test. The performed processes contributed to a significant reduction in turbidity and the value of UV254 ultraviolet absorbance, both in the ultrafiltration and nanofiltration processes. Whereas, significant differences in transport properties were noted within individual processes. A great influence of backwash water quality, including physicochemical parameters, on the course and results of the membrane filtration processes was demonstrated. In all of the nanofiltration cycles carried out, the removal of the toxic properties of the backwash water with respect to bacteria in the Microtox® test was found. Nevertheless, samples with high values of resultant physicochemical parameters after the ultrafiltration process were still characterized by high toxicity. Pressure membrane processes show high effectiveness in the removal of contaminants from backwash water. However, it is necessary to introduce supporting processes aimed at reducing membrane pore blocking by deposits and organic compounds, and in the case of ultrafiltration, assuring the safety of the purified stream in terms of the toxicological effect.

  3. Pseudomonas aeruginosa on vinyl-canvas inflatables and foam teaching aids in swimming pools.

    Science.gov (United States)

    Schets, F M; van den Berg, H H J L; Baan, R; Lynch, G; de Roda Husman, A M

    2014-12-01

    Swimming pool-related Pseudomonas aeruginosa infections mainly result in folliculitis and otitis externa. P. aeruginosa forms biofilms on surfaces in the swimming pool environment. The presence of P. aeruginosa on inflatables and foam teaching aids in 24 public swimming pools in the Netherlands was studied. Samples (n = 230) were taken from 175 objects and analysed for P. aeruginosa by culture. Isolated P. aeruginosa were tested for antibiotic resistance by disk diffusion. P. aeruginosa was detected in 63 samples (27%), from 47 objects (27%) in 19 (79%) swimming pools. More vinyl-canvas objects (44%) than foam objects (20%) were contaminated, as were wet objects (43%) compared to dry objects (13%). Concentrations were variable, and on average higher on vinyl-canvas than on foam objects. Forty of 193 (21%) P. aeruginosa isolates from 11 different objects were (intermediate) resistant to one or more of 12 clinically relevant antibiotics, mostly to imipenem and aztreonam. The immediate risk of a P. aeruginosa infection from exposure to swimming pool objects seems limited, but the presence of P. aeruginosa on pool objects is unwanted and requires attention of pool managers and responsible authorities. Strict drying and cleaning policies are needed for infrequently used vinyl-canvas objects.

  4. Swimming pool attendance and risk of asthma and allergic symptoms in children.

    NARCIS (Netherlands)

    Font-Ribera, L.; Kogevinas, M.; Zock, J.P.; Nieuwenhuijsen, M.J.; Heederik, D.; Villanueva, C.M.

    2010-01-01

    Increased asthma risk has been associated with pool attendance in children but evidence is inconsistent and inconclusive. A survey was conducted of 3,223 9-12-yr-old children in Sabadell (Spain) to evaluate association between swimming pool attendance and prevalence of asthma and allergic conditions

  5. Laboratory studies on the effect of ozonation on THM formation in swimming pool water

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Spiliotopoulou, Aikaterini; Cheema, Waqas Akram

    2015-01-01

    Water samples from indoor swimming pool were ozonated at different pH values to evaluate the effect of pH on decomposition of ozone in swimming pool water. Furthermore, drinking and pool water were repeatedly ozonated followed by chlorination to evaluate THM formation. Decomposition of ozone...... was not affected by pH in the range relevant to swimming pools (pH 6.8 – 7.8) and a half-life time at 10-12 min was obtained. Repeating the ozonation, the decomposition of ozone increased at the second dose of ozone added (t½,2=8 min) and then decreased again at the third and fourth dose of ozone (t½,3=17 min; t...... chlorine for drinking water as lower TTHM formation occurred than in non-ozonated samples. For pool water, a higher TTHM formation was observed in ozonated than non-ozonated pool water. Thus, it was observed that ozone reacts markedly different in swimming pool water from the known pattern in drinking...

  6. Monitoring organic loading to swimming pools by fluorescence excitation–emission matrix with parallel factor analysis (PARAFAC)

    DEFF Research Database (Denmark)

    Seredynska-Sobecka, Bozena; Stedmon, Colin; Boe-Hansen, Rasmus

    2011-01-01

    Fluorescence Excitation–Emission Matrix spectroscopy combined with parallel factor analysis was employed to monitor water quality and organic contamination in swimming pools. The fluorescence signal of the swimming pool organic matter was low but increased slightly through the day. The analysis...... revealed that the organic matter fluorescence was characterised by five different components, one of which was unique to swimming pool organic matter and one which was specific to organic contamination. The latter component had emission peaks at 420nm and was found to be a sensitive indicator of organic...... loading in swimming pool water. The fluorescence at 420nm gradually increased during opening hours and represented material accumulating through the day....

  7. Influence of physical activity in the intake of trihalomethanes in indoor swimming pools.

    Science.gov (United States)

    Marco, Esther; Lourencetti, Carolina; Grimalt, Joan O; Gari, Mercè; Fernández, Pilar; Font-Ribera, Laia; Villanueva, Cristina M; Kogevinas, Manolis

    2015-07-01

    This study describes the relationship between physical activity and intake of trihalomethanes (THMs), namely chloroform (CHCl3), bromodichloromethane (CHCl2Br), dibromochloromethane (CHClBr2) and bromoform (CHBr3), in individuals exposed in two indoor swimming pools which used different disinfection agents, chlorine (Cl-SP) and bromine (Br-SP). CHCl3 and CHBr3 were the dominant compounds in air and water of the Cl-SP and Br-SP, respectively. Physical exercise was assessed from distance swum and energy expenditure. The changes in exhaled breath concentrations of these compounds were measured from the differences after and before physical activity. A clear dependence between distance swum or energy expenditure and exhaled breath THM concentrations was observed. The statistically significant relationships involved higher THM concentrations at higher distances swum. However, air concentration was the major factor determining the CHCl3 and CHCl2Br intake in swimmers whereas distance swum was the main factor for CHBr3 intake. These two causes of THM incorporation into swimmers concurrently intensify the concentrations of these compounds into exhaled breath and pointed to inhalation as primary mechanism for THM uptake. Furthermore, the rates of THM incorporation were proportionally higher as higher was the degree of bromination of the THM species. This trend suggested that air-water partition mechanisms in the pulmonary system determined higher retention of the THM compounds with lower Henry's Law volatility constants than those of higher constant values. Inhalation is therefore the primary mechanisms for THM exposure of swimmers in indoor buildings. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Removal of haloacetic acids from swimming pool water by reverse osmosis and nanofiltration.

    Science.gov (United States)

    Yang, Linyan; She, Qianhong; Wan, Man Pun; Wang, Rong; Chang, Victor W-C; Tang, Chuyang Y

    2017-06-01

    Recent studies report high concentrations of haloacetic acids (HAAs), a prevalent class of toxic disinfection by-products, in swimming pool water (SPW). We investigated the removal of 9 HAAs by four commercial reverse osmosis (RO) and nanofiltration (NF) membranes. Under typical SPW conditions (pH 7.5 and 50 mM ionic strength), HAA rejections were >60% for NF270 with molecular weight cut-off (MWCO) equal to 266 Da and equal or higher than 90% for XLE, NF90 and SB50 with MWCOs of 96, 118 and 152 Da, respectively, as a result of the combined effects of size exclusion and charge repulsion. We further included 7 neutral hydrophilic surrogates as molecular probes to resolve the rejection mechanisms. In the absence of strong electrostatic interaction (e.g., pH 3.5), the rejection data of HAAs and surrogates by various membranes fall onto an identical size-exclusion (SE) curve when plotted against the relative-size parameter, i.e., the ratio of molecular radius over membrane pore radius. The independence of this SE curve on molecular structures and membrane properties reveals that the relative-size parameter is a more fundamental SE descriptor compared to molecular weight. An effective molecular size with the Stokes radius accounting for size exclusion and the Debye length accounting for electrostatic interaction was further used to evaluate the rejection. The current study provides valuable insights on the rejection of trace contaminants by RO/NF membranes. Copyright © 2017. Published by Elsevier Ltd.

  9. Health Risk Assessment from Haloacetic Acids Exposure in Indoor and Outdoor Swimming Pool Water

    Directory of Open Access Journals (Sweden)

    Weerawat Ounsanaeha

    2017-07-01

    Full Text Available The concentrations of haloacetic acids (HAAs in both indoor and outdoor swimming pools were assessed for cancer and non-cancer health risks with water samples collected during the summer and rainy seasons from two sources. Results showed that average concentrations of HAA5 (MCAA, DCAA, TCAA, MBAA, and DBAA in both indoor and outdoor pools ranged from 74.28 to 163.05 µg/L which was higher than USEPA and WHO water quality standards. Cancer and non-cancer risk values of HAA5 exposure from both swimming pool types were acceptable risks based on USEPA recommendation (10 -6-10-4 and <1, respectively. The highest cancer and non-cancer risk values of HAAs exposure were females for indoor pool and children for outdoor pool, respectively. Cancer and non-cancer risk values of HAA5 exposure from outdoor pool were higher than indoor pool and during the rainy season, respectively. Results indicated that monitoring and control of water quality and accumulated organic substance in swimming pools should be followed to maximize health risk reduction from HAA exposure.

  10. Mathematical model development of heat and mass exchange processes in the outdoor swimming pool

    Directory of Open Access Journals (Sweden)

    M. V. Shaptala

    2014-12-01

    Full Text Available Purpose. Currently exploitation of outdoor swimming pools is often not cost-effective and, despite of their relevance, such pools are closed in large quantities. At this time there is no the whole mathematical model which would allow assessing qualitatively the effect of energy-saving measures. The aim of this work is to develop a mathematical model of heat and mass exchange processes for calculating basic heat and mass losses that occur during its exploitation. Methodology. The method for determination of heat and mass loses based on the theory of similarity criteria equations is used. Findings. The main types of heat and mass losses of outdoor pool were analyzed. The most significant types were allocated and mathematically described. Namely: by evaporation of water from the surface of the pool, by natural and forced convection, by radiation to the environment, heat consumption for water heating. Originality. The mathematical model of heat and mass exchange process of the outdoor swimming pool was developed, which allows calculating the basic heat and mass loses that occur during its exploitation. Practical value. The method of determining heat and mass loses of outdoor swimming pool as a software system was developed and implemented. It is based on the mathematical model proposed by the authors. This method can be used for the conceptual design of energy-efficient structures of outdoor pools, to assess their use of energy-intensive and selecting the optimum energy-saving measures. A further step in research in this area is the experimental validation of the method of calculation of heat losses in outdoor swimming pools with its use as an example the pool of Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan. The outdoor pool, with water heating- up from the boiler room of the university, is operated year-round.

  11. Indoor heated swimming pools: the vulnerability of some infants to develop spinal asymmetries years later.

    Science.gov (United States)

    McMaster, Marianne E; Lee, A J; Burwell, R G

    2006-01-01

    Evidence reported in an earlier paper suggests that infants introduced to indoor heated swimming pools in the first year of life show an association with spinal asymmetries including progressive adolescent idiopathic scoliosis (AIS) and in normal subjects vertical spinous process asymmetry. Indoor heated swimming pools may contain a risk factor that predisposes some infants to develop such spinal asymmetries years later. What the risk factor(s) may be and its possible portal of entry into the infant's body are unknown and possibilities are examined. New teenage controls were obtained after mothers of AIS patients mentioned that they had taken their child to an infant swim class. In a further group of 18 normal teenagers introduced to an indoor heated swimming pool in the first year of life, 15 had vertical spinous process asymmetry. This prevalence of 83% of those at risk confirms our previous observation of vertical spinous process asymmetry in 61% of teenagers who were introduced to indoor heated swimming pools in the first year of life. Subject to confirmation of our observations consideration should be given to chemical risk factors, possible portals of entry, toxicology, environmental epigenomics and disease susceptibility to altered spinal development. If the risk factor is confirmed there may ultimately be a place for the prevention of AIS in some subjects.

  12. Effect of nano silica on water quality, health and safety in swimming pools

    Directory of Open Access Journals (Sweden)

    Mirmohammad Kashef

    2012-12-01

    Full Text Available The purpose of this study has been to review of using nano-silica on the efficiency of water treatment of the swimming pool. The current research was an experimental study and was performed in-vitro and experimentally. At first, a nano-particle, called "Nano-Silica", was prepared in the laboratory and herbal additives such as turmeric, curries, saffron and cinnamon were used to increase its antibacterial property. Then, for performing microbiological tests, the water samples of Urmia University's swimming pool were studied in a multi-stage process, in two parts including water samples before adding the nano-particle and after the addition of the nano-particle. Finally, to study the safety and safety, among the relevant factors, the PH and turbidity were studied in the laboratory again in two parts, including before and after the addition of the nano-particle. The survey results showed that there are averages of 2.0633 and 1.0325 before and after adding the nano-particle, respectively, which is higher (P <0.05. Among the mentioned additives, the curries with 92% and the turmeric with 85% had the most antibacterial properties. But the nano-particle did not adjust the swimming pool water PH up to the optimal level of 7.2. However, it reduced the swimming pool water turbidity significantly. This study showed that by using the nano-silica and adding the herbal additives such as cinnamon and saffron, the swimming pool water treatment has reached to a better quality. Keywords: quality, health, safety, nano silica, swimming pool.

  13. [Hygienic profile of the water in Milan swimming pools: a three-year comparative study].

    Science.gov (United States)

    Tesauro, M; Bianchi, A; Consonni, M; Bollani, M; Cesaria, M; Trolli, F Radice; Galli, M G

    2010-01-01

    The aim of this work was to determine whether swimming pool water quality in Milan from 2006 to 2008 was within the standards established by national and local Italian laws (Circolare Min. Sanità 128/71 and DGR 2552/2006). In 2006, 580 samples of water from public swimming pools were analyzed to determine the presence of heterotrophic counts at 37 degrees and total coliforms; pH, free chlorine and chloride of each sample were also measured. In the following years, water from both public and private swimming pools were examined to measure heterotrophic count at 22 degrees and 36 degrees, Escherichia coli, enterococci, Pseudomonas aeruginosa, Staphylococcus aureus, pH, free chlorine, and nitrates. The total number of analyses carried out in 2007 and 2008 was 2074 and 1532, respectively. In 2006, the extent of noncompliance of all swimming pools that was observed for both physical/chemical and microbiological parameters was 72.3%, which then decreased to 53.2% and 36.2% in 2007 and 2008, respectively. In particular with regard to the microbiological analysis, an increase of noncompliance based on at least one parameter was determined (7.1% in 2006 vs. 21.5% in 2007 and 22% in 2008). In contrast, a decrease of the extent of noncompliance based on at least one physical/chemical parameter was observed (from 68.1% in 2006 to 40.4% and 22.3% in 2007 and 2008, respectively). Interestingly, public swimming pools exceeded the legal limits of microbiological concentration more often than the private ones, whereas both types of swimming pools showed a decrease in noncompliance with regard to the physical/chemical parameters.

  14. The application of computational fluid dynamics and small-scale physical models to assess the effects of operational practices on the risk to public health within large indoor swimming pools.

    Science.gov (United States)

    Lewis, Lowell; Chew, John; Woodley, Iain; Colbourne, Jeni; Pond, Katherine

    2015-12-01

    Swimming pools provide an excellent facility for exercise and leisure but are also prone to contamination from microbial pathogens. The study modelled a 50-m × 20-m swimming pool using both a small-scale physical model and computational fluid dynamics to investigate how water and pathogens move around a pool in order to identify potential risk spots. Our study revealed a number of lessons for pool operators, designers and policy-makers: disinfection reaches the majority of a full-scale pool in approximately 16 minutes operating at the maximum permissible inlet velocity of 0.5 m/s. This suggests that where a pool is designed to have 15 paired inlets it is capable of distributing disinfectant throughout the water body within an acceptable time frame. However, the study also showed that the exchange rate of water is not uniform across the pool tank and that there is potential for areas of the pool tank to retain contaminated water for significant periods of time. 'Dead spots' exist at either end of the pool where pathogens could remain. This is particularly significant if there is a faecal release into the pool by bathers infected with Cryptosporidium parvum, increasing the potential for waterborne disease transmission.

  15. Heated indoor swimming pools, infants, and the pathogenesis of adolescent idiopathic scoliosis: a neurogenic hypothesis

    OpenAIRE

    McMaster Marianne E

    2011-01-01

    Abstract Background In a case-control study a statistically significant association was recorded between the introduction of infants to heated indoor swimming pools and the development of adolescent idiopathic scoliosis (AIS). In this paper, a neurogenic hypothesis is formulated to explain how toxins produced by chlorine in such pools may act deleteriously on the infant's immature central nervous system, comprising brain and spinal cord, to produce the deformity of AIS. Presentation of the hy...

  16. Color Fringes Bordering Black Stripes at the Bottom of a Swimming Pool

    Science.gov (United States)

    Fuster, Gonzalo; Rojas, Roberto; Slüsarenko, Viktor

    2016-01-01

    We have observed a nice example of chromatic dispersion due to refraction in water, in the form of color fringes bordering the black stripes that exist at the bottom of a swimming pool. Here we give a qualitative description of the phenomenon, explaining the role of the black stripes and the dispersive index of refraction of water.

  17. Swimming Pool Water Treatment Chemicals and/or Processes. Standard No. 22.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI.

    Chemicals or processes used or intended for use, in the treatment of swimming pool water are covered. Minimum public health limits or acceptability in regard to toxicity, biocidal effectiveness, and chemical behavior and analysis are presented. The appendices give guidelines to the scientific and statistically sound evaluations to determine the…

  18. Centrifugal Pumps for Swimming Pools. National Sanitation Foundation Standard Number 17.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI. Committee for Swimming Pool Equipment Standards.

    The pumps discussed herein are intended to be used for recirculating water in swimming pools, both public and private. Included are the basic components which may be a part of a pump such as the housing, strainer, impeller, valves, and such other parts as are attached or a part of the pump as supplied by the manufacturer. This standard is intended…

  19. The effect of UV treatment on highly polluted and normal operated swimming pools

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2017-01-01

    “It should be light blue, transparent” (Mario Andrada, speakerman, Olympic Games, Rio, 2016) was the comment for the “green lake”. Swimming pools are sensitive recirculating systems. A malfunction in water treatment units or a poor operating decision could possibly lead to health-endangering or a...

  20. Occupational exposures of airborne trichloramine at indoor swimming pools in Taipei.

    Science.gov (United States)

    Chu, Tsai-Shu; Cheng, Shu-Fang; Wang, Gen-Shuh; Tsai, Shih-Wei

    2013-09-01

    Ten indoor swimming pools in Taipei, Taiwan were included in the study to assess the exposure of people to airborne trichloramine (NCl3) and also to discover the factors that might affect the associated concentrations. An active air sampling method was performed to determine the levels of NCl3, while questionnaires were administered to swimming pool workers, including lifeguards, swimming instructors, and management employees. The results show that the concentrations of trichloramine ranged from 0.017 to 0.15 mg m(-3), which were generally lower than what have been reported from other studies. Symptoms of sore throat and phlegm were more frequent among lifeguards and swimming instructors (exposure group) than management employees (reference group) (odds ratios were 11.28 and 4.22 for sore throat and phlegm, respectively). It seems that the current exposure limit for airborne NCl3, which was recommended by WHO, was not lower enough to protect the health of pool attendants. Regulated level of free available chlorine in Taipei (i.e., 0.3-0.7 ppm) is lower than what is required in other countries (e.g., 1-3 ppm in the UK). This might be the main reason why the concentrations of NCl3 reported elsewhere were higher than what were found in this research. Further international comparisons will help to elucidate if low free chlorine concentration should be adopted as an operating standard. For the indoor swimming pools in Taipei, the air quality is suggested to be improved, since even with the low concentrations of NCl3, higher respiratory ailments among pool workers were observed. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Prevalence of dental erosion in adolescent competitive swimmers exposed to gas-chlorinated swimming pool water.

    Science.gov (United States)

    Buczkowska-Radlińska, J; Łagocka, R; Kaczmarek, W; Górski, M; Nowicka, A

    2013-03-01

    The purpose of this study was to analyze the prevalence of dental erosion among competitive swimmers of the local swimming club in Szczecin, Poland, who train in closely monitored gas-chlorinated swimming pool water. The population for this survey consisted of a group of junior competitive swimmers who had been training for an average of 7 years, a group of senior competitive swimmers who had been training for an average of 10 years, and a group of recreational swimmers. All subjects underwent a clinical dental examination and responded to a questionnaire regarding aspects of dental erosion. In pool water samples, the concentration of calcium, magnesium, phosphate, sodium, and potassium ions and pH were determined. The degree of hydroxyapatite saturation was also calculated. Dental erosion was found in more than 26 % of the competitive swimmers and 10 % of the recreational swimmers. The lesions in competitive swimmers were on both the labial and palatal surfaces of the anterior teeth, whereas erosions in recreational swimmers developed exclusively on the palatal surfaces. Although the pH of the pool water was neutral, it was undersaturated with respect to hydroxyapatite. The factors that increase the risk of dental erosion include the duration of swimming and the amount of training. An increased risk of erosion may be related to undersaturation of pool water with hydroxyapatite components. To decrease the risk of erosion in competitive swimmers, the degree of dental hydroxyapatite saturation should be a controlled parameter in pool water.

  2. Determination of Bacterial Quality of Water in Randomly Selected Swimming Pools in Kampala City, Uganda

    Directory of Open Access Journals (Sweden)

    Joyce Margaret Ekopai

    2017-01-01

    Full Text Available Swimming pools have become major recreation facilities for leisure and sports in cities across the world, but the standard guidelines, particularly in developing countries, are not adhered to because little is known about the contaminants in the pools and the possible health risks involved. This study provides a survey of bacterial quality of water from swimming pools in Kampala. A total of 26 water samples were collected from 13 outdoor swimming pools in Kampala between January and June 2016 and analysed for total aerobic plate count (TPC, Escherichia coli, coliforms, and Salmonella. The heterotrophic bacterial load ranged between 0 and 6.35 × 105 cfu/ml, where 6.35 × 105 cfu/ml was the highest load and 3 × 101 cfu/ml the least. The highest average TPC was 6.19 × 105 cfu/ml and the lowest 5.07 × 103 cfu/ml. 30.8% of the pools had TPC within acceptable limits (≤5 × 102 cfu/ml, whereas 69.2% were highly contaminated and did not conform to the Uganda National Water and Sewerage Corporation standards of recreational water quality for both treated (0 cfu/100 mls water and untreated (10 cfu/100 mls water. Although no positive results were yielded for E. coli, coliforms, and Salmonella, TPC represented the presence of heterotrophic bacteria which are often indicated in opportunistic infections.

  3. Potential risks of TiO2 and ZnO nanoparticles released from sunscreens into outdoor swimming pools

    International Nuclear Information System (INIS)

    Jeon, Soo-kyung; Kim, Eun-ju; Lee, Jaesang; Lee, Seunghak

    2016-01-01

    Highlights: • Nanoparticles from sunscreen products can be released into public pools. • Nanoparticles and organic ingredients can generate reactive oxygen species (ROS). • A negative impact of ROS should not be significant in swimming pool. - Abstract: The potential risks of nanoparticles (NPs) in sunscreens being released into swimming water were evaluated by a series of laboratory experiments simulating the fate and transport of NPs in outdoor swimming pools. NPs released from sunscreen-applied skin were estimated using pig skins covered with five different commercial sunscreens containing TiO 2 , ZnO, or both at various concentrations. Assuming that the swimming water treatment processes consisted of filtration, UV irradiation, heating, and chlorination, possible removal of the released NPs by each process was estimated. Generation of hydrogen peroxide (H 2 O 2 ) by the NPs under sunlight and after UV photochemical treatment were measured, and the H 2 O 2 concentration possibly present in the swimming pool was calculated based on some specific scenarios of operating an outdoor swimming pool. It was found that a significant amount of the NPs in sunscreens could be released into the swimming water, and accumulate during circulation through the treatment system. However, the concentration of H 2 O 2 possibly present in the swimming pool should be below the level at which an adverse effect to bathers is concerned.

  4. Potential risks of TiO{sub 2} and ZnO nanoparticles released from sunscreens into outdoor swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Soo-kyung [Center for Water Resource Cycle, Green City Technology Institute, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Energy Environment Policy and Technology, Green School, Korea University (KU)-Korea Institute of Science and Technology (KIST), Seoul 136-701 (Korea, Republic of); Kim, Eun-ju [Center for Water Resource Cycle, Green City Technology Institute, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Lee, Jaesang [Energy Environment Policy and Technology, Green School, Korea University (KU)-Korea Institute of Science and Technology (KIST), Seoul 136-701 (Korea, Republic of); Civil, Environmental, and Architectural Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Lee, Seunghak, E-mail: seunglee@kist.re.kr [Center for Water Resource Cycle, Green City Technology Institute, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Energy Environment Policy and Technology, Green School, Korea University (KU)-Korea Institute of Science and Technology (KIST), Seoul 136-701 (Korea, Republic of)

    2016-11-05

    Highlights: • Nanoparticles from sunscreen products can be released into public pools. • Nanoparticles and organic ingredients can generate reactive oxygen species (ROS). • A negative impact of ROS should not be significant in swimming pool. - Abstract: The potential risks of nanoparticles (NPs) in sunscreens being released into swimming water were evaluated by a series of laboratory experiments simulating the fate and transport of NPs in outdoor swimming pools. NPs released from sunscreen-applied skin were estimated using pig skins covered with five different commercial sunscreens containing TiO{sub 2}, ZnO, or both at various concentrations. Assuming that the swimming water treatment processes consisted of filtration, UV irradiation, heating, and chlorination, possible removal of the released NPs by each process was estimated. Generation of hydrogen peroxide (H{sub 2}O{sub 2}) by the NPs under sunlight and after UV photochemical treatment were measured, and the H{sub 2}O{sub 2} concentration possibly present in the swimming pool was calculated based on some specific scenarios of operating an outdoor swimming pool. It was found that a significant amount of the NPs in sunscreens could be released into the swimming water, and accumulate during circulation through the treatment system. However, the concentration of H{sub 2}O{sub 2} possibly present in the swimming pool should be below the level at which an adverse effect to bathers is concerned.

  5. An outbreak of adenovirus type 3 disease at a private recreation center swimming pool.

    Science.gov (United States)

    Martone, W J; Hierholzer, J C; Keenlyside, R A; Fraser, D W; D'Angelo, L J; Winkler, W G

    1980-02-01

    In the period June 6--July 24, 1977, and outbreak of illness due to adenovirus type 3 (AV3) occurred in residents of a suburban community (Community A), Dekalb County, Georgia. Based on surveys, at least 105 cases occurred. The illness was primarily characterized by sore throat, fever, headache, and anorexia. Conjunctivitis affected only 34 of 105 (32%) of the individuals in two surveys. Frequent use of a private swimming pool was associated with illness in Community A residents. The outbreak coincided with a temporary defect in the pool filtration system which probably prevented maintenance of proper chlorine levels in the pool water, and suggested that the infection was spread by pool water. However, the predominant mode of transmission could not be shown conclusively to be waterborn rather than person-to-person.

  6. Optimal pH in chlorinated swimming pools - balancing formation of by-products

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Albrechtsen, Hans-Jørgen; Andersen, Henrik Rasmus

    2013-01-01

    -products. The chlorine-to-precursor ratio used in the batch experiments influenced the amounts of by-products formed, but regardless of the ratio the same trends in the effect of pH were observed. Trihalomethane formation was reduced by decreasing pH but haloacetonitrile and trichloramine formation increased......In order to identify the optimal pH range for chlorinated swimming pools the formation of trihalomethanes, haloacetonitriles and trichloramine was investigated in the pH-range 6.5–7.5 in batch experiments. An artificial body fluid analogue was used to simulate bather load as the precursor for by.......7 or lower. An optimal pH range for by-products formation in swimming pools was identified at pH 7.0–7.2. In the wider pH range (pH 6.8–7.5) the effect on by-product formation was negligible. Swimming pools should never be maintained at lower pH than 6.8 since formation of both haloacetonitriles...

  7. Ultrafiltration for Purification and Treatment of Water Streams in Swimming Pool Circuits

    Directory of Open Access Journals (Sweden)

    Edyta Łaskawiec

    2018-05-01

    Full Text Available The paper presents possible applications of pressure-driven membrane processes for treatment of swimming pool water and purification of waste streams – washings. Newly identified swimming pool water quality issues are presented that require a modernization of existing technologies. The studies used polymer membranes with the same particle distribution range (50000 Da, but made of different membrane-forming materials: polyvinylidene difluoride (PVDF and polyether sulfone (PES for purification of washings. The ultrafiltration process allowed obtaining a high turbidity reduction rate in washings (over 95%, and also a significant reduction of total organic carbon. The effectiveness of the PES membrane was reduced after the process commencement, whereas the separation capacity of the PVDF membrane increased during the studied filtration process. While setting the operational process parameters consideration should be given also to the resistance of used membranes to chlorine present in the swimming pool water. A prolonged exposure of the polyether sulfone membrane to chloride may have caused its gradual damage and degradation of its separation properties.

  8. Occurrence ofCryptosporidiumandGiardiaand the Relationship between Protozoa and Water Quality Indicators in Swimming Pools.

    Science.gov (United States)

    Xiao, Shumin; Yin, Pengna; Zhang, Yan; Hu, Sike

    2017-04-01

    A total of 60 samples were collected from 35 swimming pools in Beijing, China, and the presence of Cryptosporidium and Giardia were investigated. The results showed that 16.7% and 15.0% of samples were positive for Cryptosporidium oocyst and Giardia cysts, respectively, with a mean concentration of 0.30 oocysts/10 L and 0.27 cysts/10 L. The oocysts and cysts were found to have higher rates of occurrence in August than in May. Genotyping confirmed the presence of Cryptosporidium hominis, C. parvum , and Giardia assemblages A and B, all of which were associated with human infections. The predominant species/assemblages were C. hominis and Giardia assemblage A. Analyses of the relationships between parasite oocysts/cysts, indicator bacteria, and physical-chemical parameters revealed that there was no correlation between 2 parasites and fecal bacterial indicators, whilst there was a significant correlation between protozoa and urea concentration, which indicates that urea concentration rather than fecal bacterial indicators might be an appropriate index for chlorine-resistant protozoa in swimming pools. This study provides useful information to improve the safety of swimming pool water and deduce the risk of protozoan infections.

  9. 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…

  10. A survey of fungi and some indicator bacteria in chlorinated water of indoor public swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Aho, R.; Hirn, J.

    1981-01-01

    Fifty-four water samples, of volume 500 ml, originating from six public indoor fresh water swimming pools were examined for the presence of fungi and some indicator bacteria by a membrane-filter method. Sabouraud-dextrose agar and selective Candida albicans-medium were used for isolation and identification of fungi. In all but one of the samples the free chlorine content was above 0.40 mg/l. No Candida albicans were detected. Molds and unidentified yeasts were isolated from 29 of the samples. The following species were recorded: Acremonium spp., ALternaria sp., Aspergillus spp., Candida guilliermondii, Chaetomium sp., Cladosporium spp., Clasterosporium sp., Fusarium spp., Geotrichium sp., Penicillium spp., Petriellidium boydii and Phoma spp. Their occurrence was sporadic, each species mostly appearing as single colonies only, with a maximum of 5 colonies. Bacterial growth was noticed in 15 samples, but only in the sample of low free chlorine content did this reach significant proportions. The study indicates that the standard of chlorination is, at least in general, an adequate measure against fungal contamination of swimming pool water. However, the spectrum of mold species encountered encourages a further search for possible indicator species among these organisms.

  11. Pseudomonas aeruginosa in Swimming Pool Water: Evidences and Perspectives for a New Control Strategy

    Directory of Open Access Journals (Sweden)

    Marco Guida

    2016-09-01

    Full Text Available Pseudomonas aeruginosa is frequently isolated in swimming pool settings. Nine recreational and rehabilitative swimming pools were monitored according to the local legislation. The presence of P. aeruginosa was correlated to chlorine concentration. The ability of the isolates to form a biofilm on plastic materials was also investigated. In 59.5% of the samples, microbial contamination exceeded the threshold values. P. aeruginosa was isolated in 50.8% of these samples. The presence of P. aeruginosa was not correlated with free or total chlorine amount (R2 < 0.1. All the isolates were moderate- to strong-forming biofilm (Optical Density O.D.570 range 0.7–1.2. To control biofilm formation and P. aeruginosa colonization, Quantum FreeBioEnergy© (QFBE, FreeBioEnergy, Brisighella, Italy, has been applied with encouraging preliminary results. It is a new, promising control strategy based on the change of an electromagnetic field which is responsible for the proliferation of some microorganisms involved in biofilm formation, such as P. aeruginosa.

  12. Isolation and identification of Acanthamoeba spp. from thermal swimming pools and spas in Southern Brazil.

    Science.gov (United States)

    Fabres, Laura Fuhrich; Rosa Dos Santos, Sayonara Peixoto; Benitez, Lisianne Brittes; Rott, Marilise Brittes

    2016-03-01

    Free-living amoebae (FLA) are widely distributed in soil and water. A few number of them are implicated in human disease: Acanthamoeba spp., Naegleria fowleri, Balamuthia mandrillaris and Sappinia diploidea. Species of Acanthamoeba can cause keratitis and brain infections. In this study, 72 water samples were taken from both hot tubs and thermal swimming pools in the city of Porto Alegre, RS, Brazil, to determine the presence of Acanthamoeba in the water as well as perform the phenotypic and genotypic characterization of the isolates. The identification of the isolates was based on the cysts morphology and PCR amplification using genus-specific oligonucleotides. When the isolates were submitted to PCR reaction only 8 were confirmed as belonging to the genus Acanthamoeba. The sequences analysis when compared to the sequences in the GenBank, showed genotype distribution in group T3 (12,5%), T5 (12,5%), T4 (25%) and T15 (50%). The results of this study confirmed the presence of potentially pathogenic isolates of free living amoebae in hot swimming pool and spas which can present risks to human health.

  13. [Investigation and comparison of behaviours of adults and children in swimming pools].

    Science.gov (United States)

    Bonini, M; Bodina, A; Bonali, D; Bascucci, B; Pellino, P; Castaldi, S

    2011-01-01

    The swimmers health's protection must be achieved through the implementation of structures that respect safety standards, the best management of the structures and the users'compliance with rules that minimize the potential risks to health, now clearly identified by the World Health Organization in specific guidelines and by the national and regional legislation. An anonymous questionnaire has been used in order to detect the level of knowledge of hygienic risks and the behaviour of costumers (adults and children) of swimming pool. Comparing the answers, statistically significant differences in the behaviours of adults and children were found in order to protect their own and others' health. In particular children do shower and go through footbath before entering the swimming pool more than adults (respectively 89.2% versus 77.4% and 89.2% versus 79.4%). No differences in the behaviours of the two groups were found in the use of dedicated footwear and caps. Children are predisposed to follow the rules because they are more loyal to duty, while adults comply with the rules only when it is clear the advantage to protect their health. This paper underline the importance of health education programs that can help people to understand the importance of adopting certain behaviours in order to prevent risks and promote health for the benefit of all.

  14. Chloroform in indoor swimming-pool air: monitoring and modeling coupled with the effects of environmental conditions and occupant activities.

    Science.gov (United States)

    Hsu, H T; Chen, M J; Lin, C H; Chou, W S; Chen, J H

    2009-08-01

    Human exposure to chloroform in indoor swimming pools has been recognized as a potential health concern. Although environmental monitoring is a useful technique to investigate chloroform concentrations in indoor swimming-pool air, in practice, the interpretations of measured data would inevitably run into difficulties due to the complex interactions among the numerous variables, including environmental conditions and occupant activities. Considering of the relevant variables of environmental conditions and occupant activities, a mathematical model was first proposed to predict the chloroform concentration in indoor swimming-pool air. The developed model provides a straightforward, conceptually simple way to predict the indoor air chloroform concentration by calculating the mass flux, J, and the Péclet number, Pe, and by using a heuristic value of the indoor airflow recycle ratio, R. The good agreement between model simulation and measured data demonstrates the feasibility of using the presented model for indoor air quality management, operational guidelines and health-related risk assessment.

  15. Blanket and vacuum vessel design of the next tokamak. (Swimming pool type)

    International Nuclear Information System (INIS)

    Iida, H.; Minato, A.; Kitamura, K.

    1983-01-01

    The structural design study of a reactor module for a swimming pool type reactor (SPTR) was conducted. Since pool water plays the role of radiation shielding in the SPTR, the module does not have a solid shield. It consists of tritium breeding blankets, divertor collector plates and a vacuum vessel. The object of this study is to show the reactor module design which has a simple structure and a sufficient tritium breeding ratio. A large coverage of the plasma chamber surface with tritium breeding blanket is essential in order to obtain a high tritium breeding ratio. A breeding blanket is also placed behind the divertor collector plate, i.e. in the upper and lower region, as well as in the outboard and inboard regions of the module. A concept in which the first wall is an integral part of the blanket is employed to minimize the thickness of structural and cooling material brazed in front of the breeding material (Li 2 O) and to enhance the tritium breeding capability. In order to simplify the module structure the vacuum vessel and breeding blanket is also integrated in the inboard region. One of the features inherent in the swimming pool type reactor is an additional external force on the vacuum vessel, namely hydraulic pressure. A detailed structural analysis of the vacuum vessel is performed. Divertor collector plates are assemblies of co-axial tubes. They minimize the electromagnetic force on the plate induced by the plasma disruption. A thermal and structural analysis and life time estimation of the first wall and divertor collector plates are performed. (author)

  16. Comparison of swimming pools alternative passive and active heating systems based on renewable energy sources in Southern Europe

    International Nuclear Information System (INIS)

    Katsaprakakis, Dimitris Al.

    2015-01-01

    This article examines different passive and active heating systems for swimming pools. The passive systems introduced in this article are: * The swimming pools' enclosure. * The placement of floating insulating covers on the pools' surfaces whenever they are not used. The examined active systems in this article are: * A biomass heater. * A biomass heater and solar collectors combi-system. * Vertical geothermal heat exchangers (GHE) co-operating with geothermal heat pumps (GHP). The methodology employed for the introduced systems' evaluation is the arithmetic computational simulation of the swimming pools' annual heating, using annual time series of averaged hourly values for the available solar radiation and the calculated pools' thermal power demand (heating loads). The dimensioning of the active systems aims at the maximisation of the heating production from R.E.S. (renewable energy sources). and the optimisation of the corresponding investments' economic indexes. The examined systems are evaluated technically and economically versus fundamental criteria. It is proved that significant reduction of the heating loads is achieved with the introduced passive systems. The reduced swimming pools' heating loads can be successfully covered by the proposed R.E.S. active systems. The fossil fuels consumption is eliminated. The corresponding investments' payback periods can be lower than 5 years. - Highlights: • The passive solar systems reduce the swimming pools heating loads more than 90%. • The examined active heating system exhibit payback periods lower than 3.5 years. • The energy saving is maximised with a biomass heater – solar collectors system. • Single biomass heaters exhibits the shortest payback period. • GHE–GHP can be used in cases of low solar radiation and lack of biomass fuels

  17. Heated indoor swimming pools, infants, and the pathogenesis of adolescent idiopathic scoliosis: a neurogenic hypothesis

    Directory of Open Access Journals (Sweden)

    McMaster Marianne E

    2011-10-01

    Full Text Available Abstract Background In a case-control study a statistically significant association was recorded between the introduction of infants to heated indoor swimming pools and the development of adolescent idiopathic scoliosis (AIS. In this paper, a neurogenic hypothesis is formulated to explain how toxins produced by chlorine in such pools may act deleteriously on the infant's immature central nervous system, comprising brain and spinal cord, to produce the deformity of AIS. Presentation of the hypothesis Through vulnerability of the developing central nervous system to circulating toxins, and because of delayed epigenetic effects, the trunk deformity of AIS does not become evident until adolescence. In mature healthy swimmers using such pools, the circulating neurotoxins detected are chloroform, bromodichloromethane, dibromochloromethane, and bromoform. Cyanogen chloride and dichloroacetonitrile have also been detected. Testing the hypothesis In infants, the putative portals of entry to the blood could be dermal, oral, or respiratory; and entry of such circulating small molecules to the brain are via the blood-brain barrier, blood-cerebrospinal fluid barrier, and circumventricular organs. Barrier mechanisms of the developing brain differ from those of adult brain and have been linked to brain development. During the first 6 months of life cerebrospinal fluid contains higher concentrations of specific proteins relative to plasma, attributed to mechanisms continued from fetal brain development rather than immaturity. Implications of the hypothesis The hypothesis can be tested. If confirmed, there is potential to prevent some children from developing AIS.

  18. Heated indoor swimming pools, infants, and the pathogenesis of adolescent idiopathic scoliosis: a neurogenic hypothesis.

    Science.gov (United States)

    McMaster, Marianne E

    2011-10-05

    In a case-control study a statistically significant association was recorded between the introduction of infants to heated indoor swimming pools and the development of adolescent idiopathic scoliosis (AIS). In this paper, a neurogenic hypothesis is formulated to explain how toxins produced by chlorine in such pools may act deleteriously on the infant's immature central nervous system, comprising brain and spinal cord, to produce the deformity of AIS. Through vulnerability of the developing central nervous system to circulating toxins, and because of delayed epigenetic effects, the trunk deformity of AIS does not become evident until adolescence. In mature healthy swimmers using such pools, the circulating neurotoxins detected are chloroform, bromodichloromethane, dibromochloromethane, and bromoform. Cyanogen chloride and dichloroacetonitrile have also been detected. In infants, the putative portals of entry to the blood could be dermal, oral, or respiratory; and entry of such circulating small molecules to the brain are via the blood-brain barrier, blood-cerebrospinal fluid barrier, and circumventricular organs. Barrier mechanisms of the developing brain differ from those of adult brain and have been linked to brain development. During the first 6 months of life cerebrospinal fluid contains higher concentrations of specific proteins relative to plasma, attributed to mechanisms continued from fetal brain development rather than immaturity. The hypothesis can be tested. If confirmed, there is potential to prevent some children from developing AIS.

  19. Radon measurements in air in waterworks and indoor swimming pools - a primary mapping project

    International Nuclear Information System (INIS)

    Marinko, J.; Mjoenes, L.; Soederman, A.-L.

    2004-01-01

    In 2001 the Swedish Work Environment Authority asked five regional offices around the country; Falun, Malmoe, Vaexjoe, Umeaa and Oerebro, to measure radon in air in workplaces where water was likely to enhance radon levels indoors. Track etch detectors were used and placed in workplaces according to the SSI measurement protocol for determining the annual average radon concentration in homes. Rooms that are frequently used by employees were measured. The detectors were exposed between 1 to 3 months. 225 detectors were used in the project and analysed at the same laboratory. The results showed that the radon concentration in waterworks often is high. Measurements were made in 60 waterworks. Levels exceeding 1000 Bq/m 3 were found in 49 of them and levels exceeding 4000 Bq/m 3 were found in 21 waterworks. The variation between waterworks may be a result of the radon concentration in the raw water, the amount of radon gas escaping to the air when water is treated, the air exchange rate in the building and where the detectors were deployed. Measurements were made in 28 indoor swimming baths. The maximum level was 290 Bq/m 3 , but most concentrations were between 30 to 70 Bq/m 3 . The conclusion is that high radon levels do not seem to be a problem in indoor swimming baths. Maybe this is due to good ventilation or the fact that water often has been treated for radon before it is used in swimming pools. The results from measurement in food industries such as breweries showed no extreme radon levels except for a fish farm where levels over 1000 Bq/m 3 were measured in the farming room and 790 Bq/m 3 in the office. The radon concentrations in laundries were relatively low, between 30 and 170 Bq/m 3

  20. Characterization of a virulent Leptospira interrogans strain isolated from an abandoned swimming pool.

    Science.gov (United States)

    Forster, Karine M; Hartwig, Daiane D; Seixas, Fabiana K; McBride, Alan J A; Monte, Leonardo G; Recuero, Ana Lúcia C; Brod, Claudiomar S; Hartleben, Cláudia P; Amaral, Marta; Dellagostin, Odir A

    2013-01-01

    Pathogenic Leptospira spp. are the etiological agents of leptospirosis, an important disease of both humans and animals. In urban settings, L. interrogans serovars are the predominant cause of disease in humans. The purpose of this study was to characterize a novel Leptospira isolate recovered from an abandoned swimming pool. Molecular characterization through sequencing of the rpoB gene revealed 100% identity with L. interrogans and variable-number tandem-repeat (VNTR) analysis resulted in a banding pattern identical to L. interrogans serogroup Icterohaemorrhagiae, serovar Copenhageni or Icterohaemorrhagiae. The virulence of the strain was determined in a hamster model of lethal leptospirosis. The lethal dose 50% (LD50) was calculated to be two leptospires in female hamsters and a histopathological examination of infected animals found typical lesions associated with severe leptospirosis, including renal epithelium degeneration, hepatic karyomegaly, liver-plate disarray and lymphocyte infiltration. This highly virulent strain is now available for use in further studies, especially evaluation of vaccine candidates.

  1. Should children be SCUBA diving?: Cerebral arterial gas embolism in a swimming pool.

    Science.gov (United States)

    Johnson, Valerie; Adkinson, Cheryl; Bowen, Mariya; Ortega, Henry

    2012-04-01

    Cerebral arterial gas embolism (CAGE) is a well-known serious complication of self-contained breathing apparatus (SCUBA) diving. Most serious complications of SCUBA diving occur in adults because most of SCUBA divers are adults. However, young age is an independent risk factor for injury in SCUBA diving and shallow-water SCUBA diving is the riskiest environment for CAGE. We present a case of a 10-year-old boy who developed CAGE while taking SCUBA diving lessons in a university swimming pool. This case illustrates the potential danger of SCUBA diving for children who lack understanding of the physics of diving as well as the often unappreciated risk of shallow-water SCUBA diving. Our intent is to educate providers of primary care to children, so that they may appropriately advise parents about SCUBA diving, and to educate providers of emergency care to children, so that they will recognize this uncommon but serious emergency condition.

  2. Trihalometanos en el agua de piscinas en cuatro zonas de España participantes en el proyecto INMA Trihalomethanes in swimming pool water in four areas of Spain participating in the INMA project

    Directory of Open Access Journals (Sweden)

    Laia Font-Ribera

    2010-12-01

    Full Text Available Objetivo: La natación es uno de los deportes más practicados en España, por personas de todas las edades y condiciones físicas. También es una vía de exposición a subproductos de la desinfección, compuestos potencialmente tóxicos. Su concentración en el agua de las piscinas no está legislada y es poco conocida. El objetivo de este trabajo es describir la concentración de trihalometanos en el agua de piscinas de los municipios de cuatro cohortes del estudio INMA. Métodos: En julio de 2009 se analizaron los trihalometanos en el agua de piscinas (n=27 de Asturias, Granada, Valencia y Sabadell. Resultados: La concentración media de trihalometanos totales fue de 42,7µg/l (desviación estándar [DE]=19,1 en las piscinas interiores y de 151,2µg/l (DE=80,7 en las exteriores, predominando siempre el cloroformo. Granada tuvo los valores más bajos. Conclusión: La concentración de trihalometanos en el agua de piscinas presenta una gran variabilidad. Las piscinas exteriores tienen valores más altos, superando mayoritariamente los límites legales establecidos para el agua de consumo.Objective: Swimming is one of the most widely practiced sports in Spain among people of all ages and physical conditions. This activity is also a source of exposure to disinfection by-products (DBP, which are potentially toxic. The DBP concentration in swimming pool water is not regulated and is poorly known. The aim of this study was to describe trihalomethane concentrations in swimming pool water in the municipalities of four cohorts of the INMA project. Methods: In July 2009, trihalomethanes were analyzed in water from 27 swimming pools in Asturias, Granada, Valencia and Sabadell. Results: The mean total trihalomethane concentration was 42.7µg/L (standard deviation [SD]=19.1 in indoor pools and 151.2µg/L (SD=80.7 in outdoor pools. In all pools, the most abundant trihalomethane was always chloroform. The lowest levels were found in Granada. Conclusion

  3. Swimming

    Science.gov (United States)

    ... re just learning to swim, stay in the shallow end. Don't push or jump on others. ... and treatment, consult your doctor. © 1995- The Nemours Foundation. All rights reserved. Images provided by The Nemours ...

  4. Surveillance and Molecular Identification of Acanthamoeba and Naegleria Species in Two Swimming Pools in Alexandria University, Egypt

    Science.gov (United States)

    AL-HERRAWY, Ahmad Z.; KHALIL, Mahmoud I.; EL-SHERIF, Soheir S.; OMAR, Fatima A. E.; LOTFY, Wael M.

    2017-01-01

    Background: Swimming in contaminated water was reported to be associated with Acanthamoeba and N. fowleri human infections. The present study was carried out with the aim of isolation and identification of the different species of Acanthamoeba and Naegleria from two swimming pools in Alexandria University. Methods: Samples were collected from the swimming pools of Alexandria University Stadium and Faculty of Agriculture-Alexandria University during the period from May 2012 to April 2013. Results: Free-living amoebae were prevalent in the collected samples. Molecular characterization confirmed the identity of ten Acanthamoeba isolates and seven Naegleria isolates. Acanthamoeba T3, T4, T5, T11 and T15 genotypes were identified. Acanthamoeba T4 was the most prevalent genotype. Conclusion: The relatively high prevalence of Acanthamoeba, especially genotype T4, indicates the presence of a health hazard to swimmers particularly those wearing contact lenses. Naegleria fowleri was not found during the present study. PMID:28761479

  5. Surveillance and Molecular Identification of Acanthamoeba and Naegleria Species in Two Swimming Pools in Alexandria University, Egypt

    Directory of Open Access Journals (Sweden)

    Ahmad Z. AL-HERRAWY

    2017-06-01

    Full Text Available Background: Swimming in contaminated water was reported to be associated with Acanthamoeba and N. fowleri human infections. The present study was carried out with the aim of isolation and identification of the different species of Acanthamoeba and Naegleria from two swimming pools in Alexandria University. Methods: Samples were collected from the swimming pools of Alexandria University Stadium and Faculty of Agriculture-Alexandria University during the period from May 2012 to April 2013.Results: Free-living amoebae were prevalent in the collected samples. Molecular characterization confirmed the identity of ten Acanthamoeba isolates and seven Naegleria isolates. Acanthamoeba T3, T4, T5, T11 and T15 genotypes were identified. Acanthamoeba T4 was the most prevalent genotype.Conclusion: The relatively high prevalence of Acanthamoeba, especially genotype T4, indicates the presence of a health hazard to swimmers particularly those wearing contact lenses. Naegleria fowleri was not found during the present study. 

  6. Siloe, Osiris, and the future perspective of swimming-pool reactors; Siloe et Osiris

    Energy Technology Data Exchange (ETDEWEB)

    Chatoux, J.; Denielou, G.; Lerouge, B. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Kervenoael, O. de [Societe INDATOM (France)

    1964-07-01

    Siloe and Osiris are two new general purpose research reactors of the 'Commissariat a l'energie Atomique'. Siloe, located within the 'Centre d'Etudes Nucleaires' of Grenoble is a swimming pool reactor of the same type as Melusine and Triton. It operates, at a nominal power of 15 MW thermal and has reached the peak power of 20 MW thermal with two thirds of its cooling system working. The fast flux above 1 MeV, which is maximum at the center of the core at 15 MW thermal is 1,2. 10{sup 14}. The core, quite open, is downward cooled. Average specific power is 159 kW/l. Osiris is under construction at Saclay. Designed for 50 MW thermal, this reactor is upward cooled. The fast flux at the center of the core above 1 MeV is calculated to be 2, 5.10{sup 14}. The average designed specific power is 280 kW/l. A fixed zircaloy gamma shield makes a box round the core. Future perspectives open to non-pressurised swimming-pool reactors are examined. Ways are suggested for neutronic; thermal and shielding modifications which make possible further improvements in the performances and economy of these devices. (authors) [French] SILOE et OSIRIS sont deux nouvelles piles de recherche non specialisees du Commissariat a l'Energie Atomique. Installee au Centre de GRENOBLE, SILOE est une pile piscine derivee de MELUSINE et TRITON. Elle fonctionne a 15 MWt en regime nominal et a ete poussee a 20 MWt avec les 2/3 de sa refrigeration en route. Le flux rapide au dessus de 1 MeV maximum au centre du coeur a 15 MWt est de 1,2 10{sup 14}. Le coeur, entierement ouvert, est refroidi en sens descendant et la puissance specifique moyenne est 150 KW/l. OSIRIS est en construction a SACLAY. Prevue pour 50 MWt thermique, cette pile est au contraire refrigeree en sens ascendant. Le flux rapide au centre du coeur au dessus de 1 MeV est de 2,5 10{sup 14} calcules. La puissance specifique moyenne prevue est de 280 KW/l de coeur. Une protection gamma fixe en zircalloy forme

  7. Characterization of a virulent Leptospira interrogans strain isolated from an abandoned swimming pool

    Directory of Open Access Journals (Sweden)

    Karine M. Forster

    2013-01-01

    Full Text Available Pathogenic Leptospira spp. are the etiological agents of leptospirosis, an important disease of both humans and animals. In urban settings, L. interrogans serovars are the predominant cause of disease in humans. The purpose of this study was to characterize a novel Leptospira isolate recovered from an abandoned swimming pool. Molecular characterization through sequencing of the rpoB gene revealed 100% identity with L. interrogans and variable-number tandem-repeat (VNTR analysis resulted in a banding pattern identical to L. interrogans serogroup Icterohaemorrhagiae, serovar Copenhageni or Icterohaemorrhagiae. The virulence of the strain was determined in a hamster model of lethal leptospirosis. The lethal dose 50% (LD50 was calculated to be two leptospires in female hamsters and a histopathological examination of infected animals found typical lesions associated with severe leptospirosis, including renal epithelium degeneration, hepatic karyomegaly, liver-plate disarray and lymphocyte infiltration. This highly virulent strain is now available for use in further studies, especially evaluation of vaccine candidates.

  8. Detection and quantification of human adenovirus genomes in Acanthamoeba isolated from swimming pools

    Directory of Open Access Journals (Sweden)

    RODRIGO STAGGEMEIER

    2016-01-01

    Full Text Available ABSTRACT Acanthamoeba is the most common free-living environmental amoeba, it may serve as an important vehicle for various microorganisms living in the same environment, such as viruses, being pathogenic to humans. This study aimed to detect and quantify human adenoviruses (HAdV in Acanthamoebas isolated from water samples collected from swimming pools in the city of Porto Alegre, Southern Brazil. Free-living amoebae of the genus Acanthamoeba were isolated from water samples, and isolates (n=16 were used to investigate the occurrence of HAdVs. HAdV detection was performed by quantitative real-time polymerase chain reaction (qPCR. HAdVs were detected in 62.5% (10/16 of Acanthamoeba isolates, ranging from 3.24x103 to 5.14x105 DNA copies per milliliter of isolate. HAdV viral loads found in this study are not negligible, especially because HAdV infections are associated with several human diseases, including gastroenteritis, respiratory distress, and ocular diseases. These findings reinforce the concept that Acanthamoeba may act as a reservoir and promote HAdV transmission through water.

  9. Electromagnetic Interference from Swimming Pool Generator Current Causing Inappropriate ICD Discharges

    Directory of Open Access Journals (Sweden)

    Edward Samuel Roberto

    2017-01-01

    Full Text Available Electromagnetic interference (EMI includes any electromagnetic field signal that can be detected by device circuitry, with potentially serious consequences: incorrect sensing, pacing, device mode switching, and defibrillation. This is a unique case of extracardiac EMI by alternating current leakage from a submerged motor used to recycle chlorinated water, resulting in false rhythm detection and inappropriate ICD discharge. A 31-year-old female with arrhythmogenic right ventricular cardiomyopathy and Medtronic dual-chamber ICD placement presented after several inappropriate ICD shocks at the public swimming pool. Patient had never received prior shocks and device was appropriate at all regular follow-ups. Intracardiac electrograms revealed unique, high-frequency signals at exactly 120 msec suggestive of EMI from a strong external source of alternating current. Electrical artifact was incorrectly sensed as a ventricular arrhythmia which resulted in discharge. ICD parameters including sensing, pacing thresholds, and impedance were all normal suggesting against device malfunction. With device failure and intracardiac sources excluded, EMI was therefore strongly suspected. Avoidance of EMI source brought complete resolution with no further inappropriate shocks. After exclusion of intracardiac interference, device malfunction, and abnormal settings, extracardiac etiologies such as EMI must be thoughtfully considered and excluded. Elimination of inappropriate shocks is to “first, do no harm.”

  10. The Confluence of Naturalism and Postmodernism in Rose Tremain’s The Swimming Pool Season: a Post-War Feminist

    OpenAIRE

    Walezak, Emilie

    2017-01-01

    Cet article entend démontrer la vitalité de l’écriture réaliste dans le monde contemporain en prenant pour exemple le roman de Rose Tremain, The Swimming Pool Season, publié en 1985. Bien que condamné par la critique structuraliste et post-structuraliste des années 70 et 80 comme véhicule de valeurs bourgeoises conservatrices, le réalisme a su se renouveler en intégrant la problématique postmoderniste de la fragmentation de l’identité. Dans The Swimming Pool Season, les références intertextue...

  11. Presentation of a calorigenic swimming-pool reactor and study of its use for urban heating, desalination of water, and other industrial applications

    International Nuclear Information System (INIS)

    Lerouge, B.

    The design characteristics of the heat-producing swimming pool reactor are discussed together with economic and technical considerations related to its utilization in the areas of district heating, process heat production, and desalination

  12. Diarrhea and Swimming

    Science.gov (United States)

    ... Pool What to Do if You Have Diarrhea Diarrhea and Swimming Diarrhea and swimming don’t mix! ... small amount of pool water to become infected. Diarrhea and Spreading Illness at the Pool Infectious diarrhea ...

  13. An Architectural Self - Criticism: The Accessibility Analysis of Berlika Park Swimming Pool

    Directory of Open Access Journals (Sweden)

    Özlem Demirkan

    2016-12-01

    Full Text Available Urban designers and architects have to clearly understand the physical features and needs of the people they are designing for. In the designing process fields such as   anthropometry, biomechanics, ergonomics, biology and physics require scientific verification to architects. But it can easily be forgotten that there are physically-challenged persons. All users experience any place by using their ability to move and perceive. If designers don’t take into account the special circumstances in the design process for physically-challenged persons, the accessibility of the place becomes impossible. At the same time a sustainable and an accessible place is truly a sign of urban rights being recognized. In this context, human rights are not only important for disciplines such as law, sociology, psychology and political sciences but also they must be important for design disciplines such as architecture, urban and interior design. This research based on the rights to exercise for physically-challenged persons aims to analyze the accessibility of the place. I was a member of the design team and today an active user of the facility-Berlika Park Swimming Pool-chosen for this study. Photographs were taken of different areas of the facility not compliant with TSE standards -TS9111 - TS 12576. Within this context, the structure was examined in terms of mobility constraints under the titles of accessible route, the arrangement of immediate surroundings of the building, arrangement of the entrance of the building, arrangement of the accessibility inside the building, signs, elevators, and fire emergency alert systems. The problematic areas of the building were identified and analyzed. This research aims to make the building more accessible place and a new modification project is being planned. But it is necessary to examine the building or the environment during its design process and solve the problems without the need of renovation project. The design

  14. Dynamic simulation and thermo-economic analysis of a PhotoVoltaic/Thermal collector heating system for an indoor–outdoor swimming pool

    International Nuclear Information System (INIS)

    Buonomano, Annamaria; De Luca, Giuseppina; Figaj, Rafal Damian; Vanoli, Laura

    2015-01-01

    Highlights: • A PV/T heating system for indoor–outdoor swimming pools is proposed. • A comparison among some thermal pool models available in literature is carried out. • Dynamic simulations of the thermal behavior of the swimming-pools are performed. • PV/T thermal energy is used to heat the swimming pool and for DHW production. • Energy and economic parametric analyses of the proposed system are presented. - Abstract: This paper presents an analysis of an innovative renewable energy plant serving an existing indoor/outdoor swimming pool located in Naples. The proposed solar hybrid system is designed in order to balance the remarkable energy demand of the swimming pool facility and to ensure suitable comfort conditions for swimmers. With the aim to accomplish such goals, the dynamic thermal behavior of the swimming pool was analyzed as a function of the thermo-hygrometric conditions of the indoor space and on the meteorological conditions of the pool site. In order to properly design and size the proposed renewable energy system, different thermal pool loss formulations for the calculation of the swimming pool thermal balance, in indoor and outdoor regimes, are adopted. The solar hybrid system consists of a water cooled photovoltaic/thermal collectors plant (PV/T), designed to meet a part of the facility demands of electricity and heat. Electricity is completely utilized by the facility, while the produced thermal energy is primarily used to meet the pool thermal demand and secondarily for sanitary hot water scopes. In order to carry out dynamic simulations and sensitivity analyses, the system performance is designed and dynamically simulated in TRNSYS environment. The developed simulation model enables the calculation of both the indoor and outdoor swimming pool thermal losses and the overall energy and economic system performance. Such results are obtained as a function of the thermo-hygrometric conditions of the environment, of the occupants and the

  15. Chemical Safety Alert: Safe Storage and Handling of Swimming Pool Chemicals

    Science.gov (United States)

    Hazards of pool water treatment and maintenance chemicals (e.g., chlorine), and the protective measures pool owners should take to prevent fires, toxic vapor releases, and injuries. Triggered by improper wetting, mixing, or self-reactivity over time.

  16. Is swimming during pregnancy a safe exercise?

    DEFF Research Database (Denmark)

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

    2010-01-01

    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...... the association between swimming in pregnancy and preterm and postterm birth, fetal growth measures, small-for-gestational-age, and congenital malformations. METHODS: We used self-reported exercise data (swimming, bicycling, or no exercise) that were prospectively collected twice during pregnancy for 74......,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...

  17. ‘Right now, Sophie *swims in the pool?!’: Brain potentials of grammatical aspect processing

    Directory of Open Access Journals (Sweden)

    Monique eFlecken

    2015-11-01

    Full Text Available We investigated whether brain potentials of grammatical aspect processing resemble semantic or morpho-syntactic processing, or whether they instead are characterized by an entirely distinct pattern in the same individuals. We studied aspect from the perspective of agreement between the temporal information in the context (temporal adverbials, e.g., Right now and a morpho-syntactic marker of grammatical aspect (e.g., progressive is swimming. Participants read questions providing a temporal context that was progressive (What is Sophie doing in the pool right now? or habitual (What does Sophie do in the pool every Monday?. Following a lead-in sentence context such as Right now, Sophie…, we measured ERPs time-locked to verb phrases in four different conditions, e.g., (a is swimming (control; (b *is cooking (semantic violation; (c *are swimming (morpho-syntactic violation; or (d?swims (aspect mismatch; …in the pool. The collected ERPs show typical N400 and P600 effects for semantics and morpho-syntax, while aspect processing elicited an Early Negativity (250-350 ms. The aspect-related Negativity was short-lived and had a central scalp distribution with an anterior onset. This differentiates it not only from the semantic N400 effect, but also from the typical (LAN (Left Anterior Negativity, that is frequently reported for various types of agreement processing. Moreover, aspect processing was not accompanied by a clear P600 modulation.We argue that the specific context for each item in this experiment provided a trigger for agreement checking with temporal information encoded on the verb, i.e., morphological aspect marking. The aspect-related Negativity obtained for aspect agreement mismatches reflects a violated expectation concerning verbal inflection (in the example above, the expected verb phrase was Sophie is X-ing rather than Sophie X-s in condition d. The absence of an additional P600 for aspect processing suggests that the mismatch did not

  18. Performance of a swimming pool heating system by utilizing waste energy rejected from an ice rink with an energy storage tank

    International Nuclear Information System (INIS)

    Kuyumcu, Muhammed Enes; Tutumlu, Hakan; Yumrutaş, Recep

    2016-01-01

    Highlights: • An analytical model of the system, and a computational program were developed. • Transient behavior of the water in the buried energy storage tank was simulated. • Effects of various system parameters on the system performance were investigated. • Long period performance of the system was analyzed and obtained periodic condition. • Optimum ice rink size is determined for a semi-Olympic size swimming pool heating. - Abstract: This study deals with determining the long period performance of a swimming pool heating system by utilizing waste heat energy that is rejected from a chiller unit of ice rink and subsequently stored in an underground thermal energy storage (TES) tank. The system consists of an ice rink, a swimming pool, a spherical underground TES tank, a chiller and a heat pump. The ice rink and the swimming pool are both enclosed and located in Gaziantep, Turkey. An analytical model was developed to obtain the performance of the system using Duhamel’s superposition and similarity transformation techniques. A computational model written in MATLAB program based on the transient heat transfer is used to obtain the annual variation of the ice rink and the swimming pool energy requirements, the water temperature in the TES tank, COP, and optimum ice rink size depending on the different ground, TES tank, chiller, and heat pump characteristics. The results obtained from the analysis indicate that 6–7 years’ operational time span is necessary to obtain the annual periodic operation condition. In addition, an ice rink with a size of 475 m 2 gives the optimum performance of the system with a semi-Olympic size swimming pool (625 m 2 ).

  19. Microbiological quality of swimming-pool waters in the province of Badajoz (Spain); Calidad microbiologica de las aguas de piscina en la provinca de Badajoz

    Energy Technology Data Exchange (ETDEWEB)

    Villalba Doblas, A. M.; Ambel Carracedo, M. P.; Cobos Rodriguez, J. G.

    2006-07-01

    The object of the actual work is to evaluate the microbiological quality of swimming pool waters in the province of Badajoz, 79 samples in 33 cities, according to criteria required by the Decreto 54/2002 of the Comunidad Autonoma of Extremadura. the work describes the possible origins of the pollution in the swimming-pool waters and the risks. The parameters analyzed were Termotolerant Coliforms, Faecal streptococci, S. aureus, P. aerogenes, Sulphate reducing bacteria and Salmonella spp. Results show that 62% of these fulfil microbiological quality criteria. the presence of Sulphate reducing bacteria was found in 24% of the samples, and P. aerogenes was detected in 16% of them. (Author) 20 refs.

  20. Evaluation of LOCA in a swimming-pool type reactor using the 3D-AIRLOCA code

    International Nuclear Information System (INIS)

    Nagler, A.; Gilat, J.; Hirshfeld, H.

    1991-01-01

    The 3D-AIRLOCA code was used to calculate core temperature evolution curves in the wake of a full LOCA in a swimming pool type reactor, resulting in complete core exposure and dryout within about 1000 sec of the initiating event. The results show that fuel integrity loss thresholds (450 C for softening and 650 C for melting) are reached and exceeded over large fractions of the core at power levels as low as 2 MW. At 4.5 MW, the softening threshold is reached even when the accident occurs up to 12 hours after reactor shutdown for continuous operation, and up to 2 hrs after shutdown for intermittent (6 hrs/day, 4 days a week) operation. The situation is even more severe in blockage cases, when the air flow through the core is blocked by residual water at the grid plate level. It is concluded that substantial fission product releases are quite likely in this class of accidents. (orig.)

  1. Evaluation of LOCA in a swimming-pool type reactor using the 3D-AIRLOCA code

    International Nuclear Information System (INIS)

    Nagler, A.; Gilat, J.; Hirshfeld, H.

    1991-01-01

    The 3D-AIRLOCA code was used to calculate core temperature evolution curves in the wake of a full LOCA in a swimming pool type reactor, resulting in complete core exposure and dryout within about 1000 sec of the initiating event. The results show that fuel integrity loss thresholds (450 C for softening and 650 C for melting) are reached and exceeded over large fractions of the core at powr levels as low as 2 MW. At 4.5 MW, the softening threshold is reached even when the accident occurs up to 12 hours after reactor shutdown for continuous operation, and up to 2 hrs after shutdown for intermittent (6 hrs/day, 4 days a week) operation. The situation is even more severe in blockage cases, when the air flow through the core is blocked by residual water at the grid plate level. It is concluded that substantial fission product releases are quite likely in this class of accidents. (orig.)

  2. Determination of neutron energy spectrum at a pneumatic rabbit station of a typical swimming pool type material test research reactor

    International Nuclear Information System (INIS)

    Malkawi, S.R.; Ahmad, N.

    2002-01-01

    The method of multiple foil activation was used to measure the neutron energy spectrum, experimentally, at a rabbit station of Pakistan Research Reactor-1 (PARR-1), which is a typical swimming pool type material test research reactor. The computer codes MSITER and SANDBP were used to adjust the spectrum. The pre-information required by the adjustment codes was obtained by modelling the core and its surroundings in three-dimensions by using the one dimensional transport theory code WIMS-D/4 and the multidimensional finite difference diffusion theory code CITATION. The input spectrum covariance information required by MSITER code was also calculated from the CITATION output. A comparison between calculated and adjusted spectra shows a good agreement

  3. On-site releases of noble gases and iodine in the event of core meltdown in a swimming pool reactor

    International Nuclear Information System (INIS)

    Montaignac, E. de.

    1976-10-01

    Research aimed at defining a standard model accident for swimming pool type reactors, has led to the adoption to the so-called BORAX accident which involves complete meltdown of the reactor core. This type of accident-an accident related to dimensional problems- is useful for calculations concerning reactor components which have to withstand the mechanical forces resulting from the accident. A study of the radiobiological consequences of this type of accident, involving the entire reactor core, required research to determine as accurately as possible how the iodine, noble gases and solid fission products are distributed between the melted core and the site. The joint document in the annexure served as the basis for discussion at the meeting (BEVS/SESR) on 9th March 1973, at which the SESR set the standard parameter values to be used for estimating fission product distributions on the site. (author)

  4. The risk of contracting infectious diseases in public swimming pools: a review

    Directory of Open Access Journals (Sweden)

    Zsófia Barna

    2012-12-01

    Full Text Available A review of pathogenic microorganisms presenting risk of infection in pool based artificial recreational water venues is extracted from the available scientific literature. The microorganisms are grouped both according to their way of spread and their survival and growth strategies and their characteristics relevant for the pool and spa based recreation are discussed. In order to put the proposed risks on a solid basis, among others a ten year excerpt of the waterborne disease statistics of the Centers for Disease Control and Prevention (CDC is used throughout the article.

  5. Maintenance operation by divers on a swimming-pool type reactor (Osiris, CEN Saclay). Technical and medical prevention: an example of multidisciplinary ergonomic step

    International Nuclear Information System (INIS)

    Arnould, C.; Martin, L.

    1979-01-01

    Maintenance works in a swimming-pool reactor was performed by a team of divers. A multidisciplinary ergonomic study had previously defined the working procedure. The ergonomic approach is analysed. The divers' working techniques are described. After work, medical tests showed that previsions were verified and proved the methods as safe. This technique by divers' interventions should open new possibilities in nuclear industry [fr

  6. Study of Microbial Contamination of the Public Swimming Pools with Escherichia coli and Pseudomonas aeruginosa and Their Physical Parameters in Kermanshah, Iran

    Directory of Open Access Journals (Sweden)

    Afsaneh Haghmorad Korasti

    2016-09-01

    Full Text Available Background and Objectives: Public swimming pools' waters are contaminated with a wide variety of pathogenic microorganisms and are a suitable environment for transmission of different diseases. The aim of this study was to investigate the microbial contamination of the public swimming pools' waters with Escherichia coli and Pseudomonas aeruginosa and to determine certain parameters such as residual chlorine, pH, temperature and turbidity in these pools' waters in Kermanshah. In this descriptive, cross-sectional study, 129 water samples were taken from all active pools in Kermanshah and their bacteriologic and physicochemical properties were investigated. Phosphatase alkaline (PHO-A gene was used for molecular confirmation of E. coli isolates, and exotoxin A (ETA gene in PCR was employed to confirm pathogenicity of P. aeruginosa isolates. Data were analyzed by chi-square and t-test. p0.05. Conclusion: The results of this study indicated that appropriate amount of residual chlorine caused reduction in microbial contamination in the public swimming pools' waters in Kermanshah.

  7. System for reducing heat losses from indoor swimming pools by use of automatic covers. Final report, October 1, 1993--September 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    This final report is an account of the principal activities of Lof Energy Systems, Inc. in a two-year project funded by the Energy Related Inventions Program (ERIP) of the U.S. Department of Energy. The primary objective has been the development of a fully practical and economical system for saving energy in indoor swimming pools by use of motorized covers. The goal is wide-spread use of a fully developed product, in institutional swimming pools. Four major tasks, depicted in the accompanying Performance Schedule, have been completed, and one other has been initiated and its completion committed. Principal accomplishments have been the selection and improvement of cover materials and designs, lengthening and strengthening of reels and improvements in motorized components and their control, design and installation of pool covers in full scale demonstration and evaluation of fully developed commercial system, preparation and dissemination of manuals and reports, finalization of arrangements for Underwriters Laboratory certification of products, and final report preparation and submission. Of greatest significance has been the successful demonstration of the fully developed system and the verification and reporting by an energy consultant of the large savings resulting from pool cover use. Probably the best evidence of success of the DOE-ERIP project in advancing this invention to a commercial stage is its acceptance for sale by the Lincoln Equipment Company, a national distributor of swimming pool supplies and equipment. A copy of the relevant page in the Lincoln catalog is included in this report as Annex A. Representatives of that company now offer Tof motorized pool cover systems to their pool owner customers. In addition to the plans for securing UL certification the company expects to continue making design improvements that can increase system reliability, durability, and cost-effectiveness.

  8. Biofilms and Oxidizing Biocides; Evaluation of Disinfection and Removal Effects by Using Established Microbial Systems.

    Science.gov (United States)

    Tachikawa, Mariko

    2017-01-01

    The formation of bacterial biofilms and their disinfection and removal have been important subjects in the maintenance of water quality in areas such as public spas, swimming pools, food processing lines, industrial water systems, and in the hygienic control of medical devices, hospital procedures, etc. Presented here is an outline of biofilm formation, as well as studies on the disinfection and removal of biofilms by oxidizing biocides using established biofilms. These studies using established biofilms may increase the understanding of the variable response of biofilms to planktonic bacteria, and the unique aspects of oxidizing biocides in the disinfection and removal of biofilms.

  9. Swimming pool cleaner poisoning

    Science.gov (United States)

    ... outcome will depend on the extent of this damage. Opening a large bucket of chlorine tablets can expose you to a powerful chlorine gas that can be very poisonous. Always open the container outdoors. Keep your face as far away from ...

  10. Swimming attendance during childhood and development of asthma: Meta-analysis.

    Science.gov (United States)

    Valeriani, Federica; Protano, Carmela; Vitali, Matteo; Romano Spica, Vincenzo

    2017-05-01

    The association between asthma and swimming pool attendance has not been demonstrated and currently there are conflicting results. In order to clarify the association between asthma diagnosis in children and swimming pool attendance, and to assess the consistency of the available epidemiological studies, we completed a literature analysis on the relationship between the exposure to disinfection by-products in indoor swimming pools during childhood and asthma diagnosis. Following the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) criteria, a systematic review and meta-analysis was performed by searching MEDLINE via PubMed, TOXNET, and Scopus databases (from inception to 20 April 2015) using the key word "Asthma" together with "swimming pool", "disinfection by-products", "indoor air pollution" and "children". Inclusion criteria were: English language, a complete analytic study design involving a cohort of children (0-16 years), a well-defined definition of exposure, and the presence of data on effect and variance. Studies on in vivo, in vitro or professional and accidental exposure were excluded. After a screening process, seven reports (n = 5851 subjects) were included out of a total of 2928 references. The reported OR of the association between swimming pool attendance and asthma prevalence ranged from 0.58 to 2.30. The present meta-analysis failed to identify a significant difference in asthma development between children attending swimming pools and controls (OR, 1.084; 95% CI: 0.89-1.31). Swimming in childhood does not increase the likelihood of doctor-diagnosed asthma. Based on this meta-analysis review, the association of the disease with indoor pool attendance is still unclear. © 2016 Japan Pediatric Society.

  11. Environmentally friendly disinfectant: Production, disinfectant action and efficiency

    Directory of Open Access Journals (Sweden)

    Čekerevac Milan I.

    2006-01-01

    Full Text Available Silver is a known disinfectant from ancient times, and it has been widely used for various purposes: for food and water disinfection, curing of wounds and as a universal antibiotic for a wide spectrum of diseases - until the Second World War and the discovery of penicillin. Until recently, it was assumed that silver, being a heavy metal, was toxic for humans and living beings. However, the newest research provides facts that the usage of silver, even for drinking water disinfection, is benign if it is added in small concentrations (in parts per billion. It has been shown in the newer scientific and technical literature that silver in colloidal form is a powerful (secondary disinfectant for drinking water, that it can be effectively used for the disinfection of water containers including swimming pools, installations in food industry, medicine, etc. Particularly, it has been shown that colloidal silver combined with hydrogen peroxide shows synergism having strong bactericidal and antiviral effects. The combination can be successfully used as a disinfectant in agriculture, food production and medicine. The original electrochemical process of production, the mechanism of physical-chemical reactions in that process and the mechanism of the antiseptic affect of the environmentally friendly disinfectant, based on the synergism of colloidal silver and hydrogen peroxide and the activity of electrochemically activated water, is shown. The starting solution was anolyte, obtained in electrochemical activation by water electrolysis of a highly diluted solution of K-tartarate in demineralized water (5.5-1CT4 M. The problem of electrolysis of very dilute aqueous solutions in membrane cells was particularly treated. It was shown that the efficiency of the electrolysis depends on the competition between the two processes: the rates of the processes of hydrogen and oxygen generation at the electrodes and the process of diffusion of hydrogen and hydroxyl ions

  12. Removals of cryptosporidium parvum oocysts and cryptosporidium-sized polystyrene microspheres from swimming pool water by diatomaceous earth filtration and perlite-sand filtration.

    Science.gov (United States)

    Lu, Ping; Amburgey, James E; Hill, Vincent R; Murphy, Jennifer L; Schneeberger, Chandra L; Arrowood, Michael J; Yuan, Tao

    2017-06-01

    Removal of Cryptosporidium-sized microspheres and Cryptosporidium parvum oocysts from swimming pools was investigated using diatomaceous earth (DE) precoat filtration and perlite-sand filtration. In pilot-scale experiments, microsphere removals of up to 2 log were obtained with 0.7 kg·DE/m 2 at a filtration rate of 5 m/h. A slightly higher microsphere removal (2.3 log) was obtained for these DE-precoated filters when the filtration rate was 3.6 m/h. Additionally, pilot-scale perlite-sand filters achieved greater than 2 log removal when at least 0.37 kg/m 2 of perlite was used compared to 0.1-0.4 log removal without perlite both at a surface loading rate of 37 m/h. Full-scale testing achieved 2.7 log of microspheres and oocysts removal when 0.7 kg·DE/m 2 was used at 3.6 m/h. Removals were significantly decreased by a 15-minute interruption of the flow (without any mechanical agitation) to the DE filter in pilot-scale studies, which was not observed in full-scale filters. Microsphere removals were 2.7 log by perlite-sand filtration in a full-scale swimming pool filter operated at 34 m/h with 0.5 kg/m 2 of perlite. The results demonstrate that either a DE precoat filter or a perlite-sand filter can improve the efficiency of removal of microspheres and oocysts from swimming pools over a standard sand filter under the conditions studied.

  13. Spectacular energy technology: Panorama-Sauna Holzweiler. KfW funds indoor swimming pools as 'process heat'; Energetisch spektakulaer: Panorama-Sauna Holzweiler. KfW foerdert Schwimmbaeder als 'Prozesswaerme'

    Energy Technology Data Exchange (ETDEWEB)

    Meissner, Rolf

    2008-11-15

    The ''Panorama-Sauna'' at Grafschaft is a big indoor swimming pool and Sauna centre in a rural region not far from Cologne and Koblenz. The charm of this spectacular solar project is in its minimalism. Conventional solar thermal power systems, in contrast, tend to be complex and prone to failure. (orig.)

  14. Frequency and Genotyping of Acanthamoeba Species in the Swimming Pools and Ponds of Khoramabad, Iran, in 2016

    Directory of Open Access Journals (Sweden)

    M. Faraji

    2017-10-01

    Full Text Available Background and Objective: Acanthamoeba is a free-living and opportunistic amoeba found in the water, soil, and air. This amoeba causes granulomatous amoebic encephalitis in the immunocompromised patients and amoebic keratitis in the people using contact lenses. The genotypes of Acanthamoeba are pathogenic and non-pathogenic. Regarding this, the present study aimed to determine the frequency and genotypes of Acanthamoeba in the water pools and ponds of Khorramabad, Iran, using culture, polymerase chain reaction (PCR, and sequencing methods in 2016. Materials and Methods: This study was conducted on a total of 84 water samples collected from the water pools and ponds of Khorramabad. The samples were filtered using nitrocellulose syringe (0.45 μm; subsequently, they were cultured on 1.5% non-nutrient agar, covered by killed Escherichia coli and incubated at 27ºC. After the extraction of DNA from positive samples, PCR was performed using specific primers to detect and confirm Acanthamoeba. Then, for genotyping, the PCR products of positive samples were sequenced. Results: Out of the 84 water samples, 50 (59.5% cases were positive for amoeba in the culture method. However, the results of the PCR revealed 35 (41.7% positive samples for Acanthamoeba. The sequencing of the PCR products demonstrated that 17 samples were T4 genotype (pathogen, and the rest were other Acanthamoeba genotypes. Conclusion: This study indicated the high prevalence of Acanthamoeba species, especially the pathogenic type, in the water pools of Khoramabad that could be a source of infection risk for humans. Regarding the fact that almost half of the found genotypes were pathogenic (genotype T4 that are the main cause of amoebic keratitis, these water bodies could be a potential risk factor for the public health. Therefore, the health professionals should prevent contamination.

  15. Protocol of actuation before occurrence of 'molluscum contagiosum' for use in public swimming pools Protocolo de actuación ante la aparición de casos de molusco contagioso en piscinas de uso público

    Directory of Open Access Journals (Sweden)

    José Ángel Bautista Cotorruelo

    2008-12-01

    Full Text Available The main objective is to develop a protocol for the disinfection of episodes of Molluscum contagiosum and establish an objective indicator. Molluscum contagiosum is a virus of Poxviridae Family. This virus produces a common infection in children that occurs when they come into direct contact with a lesion or with contaminated objects. In November 2008 is received at the Servicio de Sanidad Ambiental (Dirección General de Salud Pública, Consejería de Sanidad y Consumo, Comunidad Autónoma de la Región de Murcia a telephone call from the Epidemiology Service, which reported the existence of about 12-15 cases of children affected by Molluscum contagiosum. In addition, they indicated us that the suspicions fell on the Municipal Pool Cover Alhama de Murcia. Immediately we contacted the responsible staff and we send them a protocol developed with information from several sources. The analysis of articles used for water activities showed absence of Molluscum contagiosum. We selected "absence of molds and yeasts” as indicator. All this coincided with the disappearance of the cases. Months later, in March 2009 we detected new cases of children affected in another pool in the town of Alcantarilla. Due to the success of the methodology used in the earlier incident we performed the same actions and we obtained the same results. The protocol developed by this Service is effective to avoid the occurrence of more cases. We propose the “absence of molds and yeasts” as an indicator to evaluate the presence of Molluscum contagiosum. Coinciding with the update of the rules of public swimming pools in our Region we have introduced an article that indicates that the objects used for water activities must be disinfected after each use.El objetivo principal fue elaborar un protocolo de actuación para el caso de episodios de infección de molusco contagioso y un indicador objetivo, que nos permita hacer un seguimiento. El virus del molusco contagioso

  16. Bakteri Legionella pneumophila Terdeteksi pada Air Kolam Renang di Kota Surabaya dengan Nested Polymerase Chain Reaction (LEGIONELLA PNEUMOPHILA BACTERIADETECTED IN SWIMMING POOL WATER OF SURABAYA BY USING NESTED POLYMERASE CHAIN REACTION

    Directory of Open Access Journals (Sweden)

    Eduardus Bimo Aksono

    2017-06-01

    Full Text Available Legionella pneumophila is a Gram-negative bacillus that causes nosocomial and community-acquired pneumonia. The aim of this research was to detect the presence of bacteria of L. pneumophila species in the swimming pools water of Surabaya city by using nested Polymerase Chain Reaction (PCR assay of a specific gene for L. pneumophila (mip gene. This study used purposive sampling method. A total of 10 water samples were collected from five swimming pools consisting of 200 mL water for each swimming pool. The results showed that of 10 samples tested by nested PCR, one sample was positive for L. pneumophila, and nine samples were negative. L. pneumophila were found in pool water samples with a higher temperature (>30ºC.Serogrouping analysis of positive sample that L. pneumophila bacteria detected in the water sample of swimming pool in Surabaya was L. pneumophila serogroup 9 (98% and serogroup 10 (98%. L. pneumophila detection of bacteria is expected to raise the awareness of physician and microbiologists about the transmission of L. pneumophila and will also be useful for controlling the agents. ABSTRAK Legionella pneumophila adalah bakteri Gram-negatif berbentuk batang yang dapat menyebabkan penyakit nosokomial dan pneumonia. Tujuan penelitian ini adalah untuk mendeteksi keberadaan bakteri L. pneumophila pada air kolam renang di Kota Surabaya dengan menggunakan nested Polymerase Chain Reaction (PCR berbasis gen spesifik L. pneumophila (mip gene. Penelitian ini menggunakan metode purposive sampling. Sebanyak sepuluh sampel diambil dari lima kolam renang. Sampel diambil sebanyak 200 mL dari air kolam renang di setiap lokasi. Hasil dari 10 sampel yang diuji menggunakan nested PCR, satu sampel menunjukkan hasil positif untuk L.pneumophila, dan sembilan sampel menunjukkan hasil negatif. Bakteri L. pneumophila ditemukan pada sampel air kolam dengan suhu yang lebih tinggi (>30ºC. Satu sampel positip tersebut ketika dilanjutkan terhadap analisis serogrup

  17. Swimming performance in surf: the influence of experience.

    Science.gov (United States)

    Tipton, M; Reilly, T; Rees, A; Spray, G; Golden, F

    2008-11-01

    This study tested the hypothesis (H1) that surf swimming involves a quantifiable experience component. Sixty-five beach lifeguards with (n = 35) and without surf experience (n = 30) completed: a best effort 200-m swim in a 25-m pool, a calm and a surf sea; an anthropometric survey; maximum effort 30-s swim bench test; 50-m pool swim (25 m underwater). In both groups, time to swim 200 m was slower in calm seas than in the pool and slower in surf than in either calm seas or the pool (p surf conditions (p surf experience as a predictor of surf swim time (R(2) = 0.32, p surf swimming. This limits the usefulness of pool swim times and other land-based tests as predictors of surf swimming performance. The hypothesis (H1) is accepted.

  18. Geneva 24 hours swim

    CERN Multimedia

    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

  19. Geneva 24 Hours Swim

    CERN Multimedia

    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

  20. The solar heating system of the sport centre 'Guillamo Swimming Pool' in Sierre, Switzerland; Installation solaire thermique. Complexe sportif de la piscine de Guillamo - Rapport final

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This illustrated report for the Swiss Federal Office of Energy describes the refurbishment and the extension of the sport centre 'Guillamo Swimming Pool' in Sierre, Switzerland. The original building built in 1978 included three swimming pools (two indoor and one small outdoor). In 2005 a three-room fitness centre, a wellness centre and a bar were added to the compound and the old building and technical installations refurbished. At the same time a 591 m{sup 2} solar collector array was added. Unglazed selective solar absorbers were mounted on the 5{sup o} tilted flat roof. They insure at the same time the water tightness of the roof, a feature that lead to a significant cost reduction of the project. Before 2005 the natural gas consumption of the centre was 1.3 to 1.7 GWh/year. After the construction work the consumption was about 1.6 GWh, including a contribution of 0.06 GWh from the solar collectors. This last figure is disappointing. The reasons for this are mainly attributed by the authors to a very poor integration of the solar collectors into the conventional heat generation and distribution system, which do not enable the solar collectors to deliver the heat quantity they should. Changes should be made on the hydraulics of the whole system and on the control algorithms and settings.

  1. 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.

  2. Contaminación del aire interior y del agua de baño en piscinas cubiertas de Guipúzcoa Indoor air and bathing water pollution in indoor swimming pools in Guipúzcoa (Spain

    Directory of Open Access Journals (Sweden)

    Loreto Santa Marina

    2009-04-01

    Full Text Available Objetivo: Describir los niveles de contaminantes presentes en las piscinas cubiertas de Guipúzcoa, tanto en el agua de baño como en el aire, y estudiar la relación entre estos contaminantes y otras variables relacionadas con los sistemas de ventilación y el uso de las instalaciones. Métodos: De las 35 piscinas cubiertas registradas en Guipúzcoa se estudiaron las 20 más utilizadas por nadadores. Cada instalación se muestreó 2 días no consecutivos y se midieron los niveles de cloro libre y combinado y trihalometanos en el agua, así como los de cloro total y cloroformo en el aire. Como indicador de la renovación del aire se midió el dióxido de carbono (CO2. Resultados: El nivel medio de cloro en el aire fue de 0,4mg/m³ y el de cloroformo de 22µg/m³. Los valores de cloro libre y combinado de todas las piscinas se mantuvieron dentro de los valores reglamentarios. El nivel medio de cloroformo del agua de baño fue de 13,7µg/l. El valor del cloroformo del aire puede predecirse razonablemente (R²=0,85, y las variables predictoras son el cloroformo del agua, el CO2 y el número de bañistas del día. Conclusiones: Los niveles de contaminantes en el agua y en el aire de las piscinas de Guipúzcoa son inferiores a los descritos en otros estudios. Sin embargo, utilizando la concentración de 0,5mg/m³ de cloro total en aire, propuesta como valor de referencia para la protección de los nadadores con actividad intensa, un 20% de las instalaciones superarían dicho valor.Objective: To describe levels of pollutants found in indoor swimming pools in Guipúzcoa (Basque Country, Spain, both in the bathing water and in the air, and to study the association between these pollutants and other variables related to ventilation systems and the use of installations. Methods: Of the 35 indoor swimming pools registered in Guipúzcoa, the 20 most frequently used by swimmers were studied. Each installation was sampled on two nonconsecutive days. Free and

  3. Swimming physiology.

    Science.gov (United States)

    Holmér, I

    1992-05-01

    Swimming takes place in a medium, that presents different gravitational and resistive forces, respiratory conditions and thermal stress compared to air. The energy cost of propulsion in swimming is high, but a considerable reduction occurs at a given velocity as result of regular swim training. In medley swimmers the energy cost is lowest for front crawl, followed by backstroke, butterfly and breast-stroke. Cardiac output is probably not limiting for performance since swimmers easily achieve higher values during running. Maximal heart rate, however, is lowered by approx. 10 beats/min during swimming compared to running. Most likely active muscle mass is smaller and rate of power production lesser in swimming. Local factors, such as peripheral circulation, capillary density, perfusion pressure and metabolic capacity of active muscles, are important determinants of the power production capacity and emphasize the role of swim specific training movements. Improved swimming technique and efficiency are likely to explain much of the continuous progress in performance. Rational principles based on improved understanding of the biomechanics and physiology of swimming should be guidelines for swimmers and coaches in their efforts to explore the limits of human performance.

  4. Ultraviolet light in the use of water disinfection

    International Nuclear Information System (INIS)

    Dabbagh, R.

    1999-01-01

    Ultraviolet light is an effective method in the use of water disinfection for swimming pools, potable water and industry required water. For many reasons UV light and UV compounded with chlorine (UV/chlorine) has been brought to attention in resent years. In this research, a swimming pool water disinfection was carried out by means of a system with the use of a reactor which was made of stainless steel (SS-304) and with many another standards required. Operation of system was carried out at first in the pilot plant and then installation in essential water treatment integrated. Inactivation of pollution index, E. Coli or Total coliform and Pseudomonas aeroginosa studied with 6000,16000 and 30000 μW.s/cm 2 UV dose and then in presence of 0.3,0.6,0.9 and 1.2 mg/1 free chlorine (UV/chlorine). In swimming pools minimum free chlorine residual usually is 1.5 mg/1. Optimum UV dose was 16000 μW.s/cm 2 attention to 50 percent UV absorption caused to TSS,TDS and turbidity. In the UV/chlorine system suitable rate was 16000μW.s/cm 2 UV dose /0.6 mg/1 chlorine in the 2.4 * 10 5 CFU/100 ml for Total coliform and 3600CFU/100 ml for Pseudomonas aeroginosa. Most probable number(MPN) estimated multiple tube fermentation technique. In this way the flow rate for system indicated about 240 cm 3 /s or 0.9 m 3 /h. The samples polluted for secondary pollution with 54000 CFU/100 ml for E.Coli and 1800 CFU/100ml Pseudomonas aeroginosa. The number of microbes decreased to zero duration after 45 minutes contact time in presence of free chlorine residual in samples. In practical conditions which that disinfectant system was installed in essential water treatment circuit under 1.4 atm hydraulic pressure no growth was seen for pollution index in disinfected water with UV in microbial density about 840 CFU/100 ml for Total coliform and 12CFU/100 ml for Pseudomonas aeroginosa. Attention to lower turbidity, TSS and TDS in tap water, higher flow rate about 560 cm 3 /s or 2 m 3 /h acessesed

  5. Training optimization of swimming of school-age children

    OpenAIRE

    Hudcová, Stanislava

    2011-01-01

    Subject matter: Training optimization of swimming of school-age children Objectives: The main goal of this research work is to suggest a model of advanced swimming training lessons with school-age children. Swimming training is practised in deep swimming pool. Next goal is to create an inventory of games and game disciplines which are suitable for training in deep water. Through the analysis of specialized literature and realization of experimental education we will be able to formulate new p...

  6. Strategies for chemically healthy public swimming pools

    OpenAIRE

    Hansen, Kamilla Marie Speht; Andersen, Henrik Rasmus; Albrechtsen, Hans-Jørgen; Mosbæk, Hans

    2013-01-01

    I Danmark er offentlige svømmebade en vigtig mulighed for rekreative aktiviteter og fysisk træning samt et redskab for genoptræning. Tilsætning af klor anvendes altid til at kontrollere vand¬kvaliteten og hindre spredning af infektioner mellem badende. Klor oxiderer vandforureningen fra de badende, hvilket holder bassinvandet rent, men der dannes klorerede desinfektions¬biprodukter. Der er identificeret mere end 100 klorbiprodukter i svømme¬bads¬vand, hvor nogle har vist sig at være genotoksi...

  7. Improving Pool Fencing Legislation in Queensland, Australia: Attitudes and Impact on Child Drowning Fatalities.

    Science.gov (United States)

    Franklin, Richard C; Peden, Amy E

    2017-11-24

    Four-sided, non-climbable pool fencing is an effective strategy for preventing children from drowning in home swimming pools. In 2009, the Queensland Government introduced legislation to improve the effectiveness of pool fencing. This study explores community attitudes towards the effectiveness of these legislative changes and examines child (houses with swimming pools) are protected.

  8. 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

  9. Efeitos de oito semanas de treinamento de natação no limiar anaeróbio determinado na piscina e no ergômetro de braço Effect of eight weeks of swimming training on the anaerobic threshold determined in the swimming pool and by arm ergometer

    Directory of Open Access Journals (Sweden)

    Fabrizio Caputo

    2002-02-01

    Full Text Available O objetivo deste estudo foi analisar os efeitos do treinamento de natação na intensidade do limiar anaeróbio (LAn, determinado na piscina e no ergômetro de braço, verificando se este pode ser utilizado para avaliar os efeitos do treinamento em nadadores. Participaram do estudo sete nadadores de ambos os sexos, com nível de performance regional, que foram submetidos aos seguintes testes, antes e após oito semanas de treinamento: 1 dois tiros de 400m, um a 85% e outro a 95% do máximo, com coleta de 25mil de sangue do lóbulo da orelha no 1º, 3º e 5º minuto após cada tiro, para posterior análise do lactato sanguíneo (YSI 1500; 2 teste contínuo progressivo realizado no ergômetro de braço (UBE 2462 Cybex, com carga inicial de 33,3W e incrementos de 16,6W a cada três minutos até a exaustão voluntária, com coleta de sangue ao final de cada estágio. Um grupo controle de indivíduos não ativos (n = 9, que se manteve sedentário, realizou somente o procedimento 2 no mesmo intervalo de tempo. O LAn na natação (NLAn e no ergômetro de braço (BLAn foi encontrado através de interpolação linear, considerando uma concentração fixa de lactato de 4mM e 3,5mM, respectivamente. Os resultados demonstram diferença significante para o grupo treinado, entre o pré (130,4 ± 20,4W e o pós-teste (137,7 ± 17,9W para o BLAn. Porém, não foi encontrada diferença significante para o NLAn (1,09 ± 0,1m.s-1 e 1,13 ± 0,1m.s-1, p = 0,06. No grupo controle não foi encontrada diferença para o BLAn entre o pré (93,2 ± 11,5W e o pós-teste (87,7 ± 7,2W. Pode-se concluir através desses dados que a determinação do LAn no ergômetro de braço é útil para detectar adaptações na capacidade aeróbia de nadadores com nível de performance regional.The objective of this study was to analyze the effect of swimming training on the intensity corresponding to the anaerobic threshold (AnT determined in the swimming pool and by arm ergometer, and

  10. 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

  11. Spiral-shaped disinfection reactors

    KAUST Repository

    Ghaffour, Noreddine

    2015-08-20

    This disclosure includes disinfection reactors and processes for the disinfection of water. Some disinfection reactors include a body that defines an inlet, an outlet, and a spiral flow path between the inlet and the outlet, in which the body is configured to receive water and a disinfectant at the inlet such that the water is exposed to the disinfectant as the water flows through the spiral flow path. Also disclosed are processes for disinfecting water in such disinfection reactors.

  12. ARC Code TI: Swim

    Data.gov (United States)

    National Aeronautics and Space Administration — Swim is a software information service for the grid built on top of Pour, which is an information service framework developed at NASA. Swim provides true software...

  13. 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....

  14. 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.

  15. 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.

  16. Evolución del grado de implantación de programas de autocontrol en las piscinas de temporada en Araba/Álava Evolution of the implementation level of self-monitoring programmes for outdoor swimming pools in Araba/Álava Evolução do grau de implementação de programas de autocontrolo em piscinas sazonais em Araba/Álava

    Directory of Open Access Journals (Sweden)

    Arantza Armentia Álvarez

    2012-12-01

    Full Text Available El objetivo principal de este estudio ha sido realizar una valoración de la evolución del grado de implantación de programas de autocontrol en las piscinas descubiertas de Araba/Álava durante seis años (2006-2011. Para ello, en las inspecciones se cumplimentaron protocolos de comprobación basados en instrucciones técnicas, elaboradas para aunar criterios y valorar los diferentes planes del Programa de autocontrol (Estos planes son: 1. Tratamiento y vigilancia del agua; 2. Análisis del agua; 3. Limpieza y desinfección; 4. Seguridad, buenas prácticas e información al usuario; 5. Revisión y mantenimiento; 6. Control de plagas; 7. Proveedores, productos y servicios. Además, se usó una valoración consensuada de cada plan, con el fin de valorar objetivamente las instalaciones y la implantación del autocontrol.The main aim of this study was to carry out an assessment of the implementation level of the self-monitoring programme for outdoor swimming pools in Araba/Álava over a six-year period (2006-2011. For this purpose, inspections were carried out using checklists based on technical guidelines designed to unify criteria and assess the different plans within each self-monitoring programme, including the following: 1. Water Treatment and Monitoring; 2. Water analysis; 3. Cleansing and Disinfection; 4. Safety, Best Practices and User information; 5. Inspection and Maintenance; 6. Pest control; 7. Suppliers, Products and Services. Consensus-based assessments of each plan were also used to objectively evaluate the facilities and the level of implementation of the self-monitoring programme.Este estudo teve como objectivo principal realizar uma avaliação da evolução do grau de implementação de programas de auto controlo nas piscinas descobertas de Álava durante um período de seis anos (2006-2011. Nesse sentido, foram realizadas inspeções técnicas respeitando protocolos assentes em listas de verificação, destinados a unificar

  17. Applications of Photocatalytic Disinfection

    Directory of Open Access Journals (Sweden)

    Joanne Gamage

    2010-01-01

    Full Text Available Due to the superior ability of photocatalysis to inactivate a wide range of harmful microorganisms, it is being examined as a viable alternative to traditional disinfection methods such as chlorination, which can produce harmful byproducts. Photocatalysis is a versatile and effective process that can be adapted for use in many applications for disinfection in both air and water matrices. Additionally, photocatalytic surfaces are being developed and tested for use in the context of “self-disinfecting” materials. Studies on the photocatalytic technique for disinfection demonstrate this process to have potential for widespread applications in indoor air and environmental health, biological, and medical applications, laboratory and hospital applications, pharmaceutical and food industry, plant protection applications, wastewater and effluents treatment, and drinking water disinfection. Studies on photocatalytic disinfection using a variety of techniques and test organisms are reviewed, with an emphasis on the end-use application of developed technologies and methods.

  18. Effect of the starting and turning performances on the subsequent swimming parameters of elite swimmers.

    Science.gov (United States)

    Veiga, Santiago; Roig, Andreu

    2017-03-01

    In the present research, we examined the effect of the starting and turning performances on the subsequent swimming parameters by (1) comparing the starting and turning velocities with the swimming parameters on the emersion and mid-pool segments and (2) by relating the individual behaviour of swimmers during the start and turns with subsequent behaviour on each swimming lap. One hundred and twelve 100 m performances on the FINA 2013 World Swimming Championships were analysed by an image-processing system (InThePool 2.0®). At the point of the start emersion, the swimming parameters of the 100-m elite swimmers were substantially greater than the mid-pool parameters, except on the breaststroke races. On the other hand, no diminution in the swimming parameters was observed between the turn emersion and the mid-pool swimming, except on the butterfly and backstroke male races. Changes on the surface swimming kinematics were not generally related to the starting or turning parameters, although male swimmers who develop faster starts seem to achieve faster velocities at emersion. Race analysts should be aware of a transfer of momentum when swimmers emerge from underwater with implications on the subsequent swimming kinematics, especially for male swimmers who employ underwater undulatory techniques.

  19. 76 FR 62605 - Virginia Graeme Baker Pool and Spa Safety Act; Interpretation of Unblockable Drain

    Science.gov (United States)

    2011-10-11

    ... 19, 2008. The VGB Act's purpose is to prevent suction entrapment by swimming pool and spa drains and child drowning in swimming pools and spas. Section 1404(c)(1)(A)(i) of the VGB Act requires that each... area (beyond the shadowed portion) cannot create a suction force in excess of the removal force values...

  20. Humidifier disinfectants, unfinished stories

    Directory of Open Access Journals (Sweden)

    Yeyong Choi

    2016-02-01

    Full Text Available Once released into the air, humidifier disinfectants became tiny nano-size particles, and resulted in chemical bronchoalveolitis. Families had lost their most beloved members, and even some of them became broken. Based on an estimate of two million potential victims who had experienced adverse effects from the use of humidifier disinfectants, we can say that what we have observed was only the tip of the iceberg. Problems of entire airways, as well as other systemic effects, should be examined, as we know these nano-size particles can irritate cell membranes and migrate into systemic circulation. The story of humidifier disinfectant is not finished yet.

  1. Vernal Pools

    Data.gov (United States)

    California Department of Resources — This is a polygon layer representing existing vernal pool complexes in California's Central Valley, as identified and mapped by Dr. Robert F. Holland. The purpose of...

  2. 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

  3. A Guide to Swimming Instruction for Developmentally Disabled Children. Report Number 8168.

    Science.gov (United States)

    Noble, Susan

    The swimming instruction guide presents teaching techniques and skill progressions for developmentally disabled individuals and includes program development and administrative guidelines. Part 1 discusses swimming and developmentally disabled children, program planning and preparation elements (including pool, scheduling, staff, parents,…

  4. Chemical and microbial decontamination of pool water using activated potassium peroxymonosulfate.

    Science.gov (United States)

    Anipsitakis, George P; Tufano, Thomas P; Dionysiou, Dionysios D

    2008-06-01

    Potassium peroxymonosulfate activation leads to the formation of highly reactive species, mainly the sulfate radicals. Activated potassium peroxymonosulfate (from now on peroxymonosulfate) was tested against specific pollutants such as ammonium ion, creatinine, chlorinated creatinine products, arginine and Escherichia coli (E. coli), all constituents or derivatives of human discharges. The objective was to assess whether activated peroxymonosulfate can be a viable treatment reagent in recreational water applications. It was found that organic molecules such as creatinine, chlorinated creatinine products and arginine could be effectively treated with activated peroxymonosulfate. Ammonium ion was oxidized only by chlorine species and only in de-ionized water. Chlorine species were formed from the reaction of sulfate radicals with chloride ions. In pool water, the reaction of sulfate radicals with chloride ions and the subsequent ammonium ion oxidation were scavenged by the presence of bicarbonate ions. The Co/Peroxymonosulfate system was also shown to be an effective disinfection reagent, since 99.99% (4-log) kill of E. coli was achieved in 60 min of treatment. At the concentrations tested here, however, it is still not efficacious enough to qualify as an EPA-registered sanitizer for swimming pools (requires 6-log kill of E. coli, ATCC 11229, and Enterococcus faecium, ATCC 6569, in 30s).

  5. 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.

  6. Independent Swimming for Children with Severe Physical Impairments.

    Science.gov (United States)

    Grosse, Susan J.; McGill, Christine D.

    1979-01-01

    Techniques are described for teaching severely physically disabled persons to swim. Approaches begin with a discussion of water adjustment progression and proceed through achieving breath control, mobility, developing movement in a supine position, and developing recovery. The conclusion addresses such final steps toward independence as pool entry…

  7. 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.

  8. [The effect of swimming on the nasal passages and on tube function in children].

    Science.gov (United States)

    Desterbeck, R A; Stoop, A; Franckx, H; Clement, P A; Kaufman, L; Rousseeuw, P

    1984-01-01

    In two studies the authors want to confirm experimentally what is assumed in every day ENT-practice: otitis and sinusitis are not infrequent complications of swimming. The first study, involving 60 children with chronic non-specific lung diseases shows that swimming in a sea water pool increases the nasal airway resistance during two days. In the second study, performed in 32 normal children swimming in a chlorous pool, a negative relationship is found between the number of days after the swimming and the increased nasal airway resistance. Probably other factors also play a part in this phenomenon. Due to the too small number of children showing an otitis media with effusion, the influence of swimming on the function of the Eustachian tube could not be determined.

  9. The pool chlorine hypothesis and asthma among boys.

    LENUS (Irish Health Repository)

    Cotter, A

    2012-01-31

    Swimming pool sanitation has largely been concerned with the microbiological quality of pool water, which is normally treated using a number of chlorine products. Recent studies have pointed to the potential hazards of chlorine by-products to the respiratory epithelium, particularly in indoor, poorly ventilated, pools. The aim of our study was to elucidate whether chronic exposure to indoor chlorinated swimming pools was associated with an increased likelihood of the development of asthma in boys. METHODS: The subjects were boys aged between 6 and 12 years. Data was collected by means of parental responses to a standardized asthma questionnaire (ISAAC: International Study of Asthma and Allergies in Childhood), supplemented with additional questions regarding frequency of attendance, number of years attendance, whether the child is a swimming team member. The questionnaire return rate was 71\\/% (n = 121). 23 boys were excluded on the basis that they had asthma before they started swimming (n = 97). There was a significant association between number of years a boy had been swimming and the likelihood of wheezing in the last 12 months (p = 0.009; OR = 1.351; 95% CI = 1.077-1.693) and diagnosed asthma (p = 0.046; OR = 1.299; 95% CI = 1.004-1.506). The greater the number the number of years a boy had been attending an indoor, chlorinated pool, the greater the likelihood of wheezing in the last 12 months or "had asthma". Age, parental smoking habits and being a swimming team member had no association with any of the asthma variables examined. Swimming pool attendance may be a risk factor in asthma in boys.

  10. 2007 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.

  11. 2006 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.

  12. 2009 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.

  13. 2008 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.

  14. 2010 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.

  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. Disinfection of sewage

    International Nuclear Information System (INIS)

    Arenas, J.

    1984-01-01

    Laboratory studies at IPEN and SEDAPAL have shown the effectiveness disinfection of sewage by means of ionizing radiations. A dose of 1 Kilo Gray reduces the coliforms and salmonella under the permissible levels. This method should allow to use again the liquids in the agriculture or its disposal like sea nutrient

  17. 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 ...... movements (0.64 ≤ r ≤ 0.75). The correlation coefficients are (0.75 ≤ r ≤ 0.83) and (0.82 ≤ r ≤ 0.89) for the other two axes....

  18. Pool scrubbing

    International Nuclear Information System (INIS)

    Lopez-Jimenez, J.; Herranz, J.; Escudero, M.J.; Espigares, M.M.; Peyres, V.; Polo, J.; Kortz, Ch.; Koch, M.K.; Brockmeier, U.; Unger, H.; Dutton, L.M.C.; Smedley, Ch.; Trow, W.; Jones, A.V.; Bonanni, E.; Calvo, M.; Alonso, A.

    1996-12-01

    The Source Term Project in the Third Frame Work Programme of the European Union Was conducted under and important joined effort on pool scrubbing research. CIEMAT was the Task Manager of the project and several other organizations participated in it: JRC-Ispra, NNC Limited, RUB-NES and UPM. The project was divided into several tasks. A peer review of the models in the pool scrubbing codes SPARC90 and BUSCA-AUG92 was made, considering the different aspects in the hydrodynamic phenomenology, particle retention and fission product vapor abortions. Several dominant risk accident sequences were analyzed with MAAP, SPARC90 and BUSCA-AUG92 codes, and the predictions were compared. A churn-turbulent model was developed for the hydrodynamic behaviour of the pool. Finally, an experimental programme in the PECA facility of CIEMAT was conducted in order to study the decontamination factor under jet injection regime, and the experimental observations were compared with the SPARC and BUSCA codes. (Author)

  19. In the making: SA-PIV applied to swimming practice

    Science.gov (United States)

    van Houwelingen, Josje; van de Water, Willem; Kunnen, Rudie; van Heijst, Gertjan; Clercx, Herman

    2017-11-01

    To understand and optimize the propulsion in human swimming, a deep understanding of the hydrodynamics of swimming is required. This is usually based on experiments and numerical simulations under laboratory conditions.. In this study, we bring basic fluid mechanics knowledge and experimental measurement techniques to analyze the flow towards the swimming practice itself. A flow visualization setup is build and placed in a regular swimming pool. The measurement volume contains five homogeneous air bubble curtains illuminated by ambient light. The bubbles in these curtains act as tracer particles. The bubble motion is captured by six cameras placed in the side wall of the pool. It is intended to apply SA-PIV (synthetic aperture PIV) for analyzing the flow structures on multiple planes in the measurement volume. The system has been calibrated and the calibration data are used to refocus on the planes of interest. Multiple preprocessing steps need to be executed to obtain the proper quality of images before applying PIV. With a specially programmed video card to process and analyze the images in real-time feedback about swimming performance will become possible. We report on the first experimental data obtained by this system.

  20. Swimming performance assessment in fishes.

    Science.gov (United States)

    Tierney, Keith B

    2011-05-20

    Swimming performance tests of fish have been integral to studies of muscle energetics, swimming mechanics, gas exchange, cardiac physiology, disease, pollution, hypoxia and temperature. This paper describes a flexible protocol to assess fish swimming performance using equipment in which water velocity can be controlled. The protocol involves one to several stepped increases in flow speed that are intended to cause fish to fatigue. Step speeds and their duration can be set to capture swimming abilities of different physiological and ecological relevance. Most frequently step size is set to determine critical swimming velocity (U(crit;)), which is intended to capture maximum sustained swimming ability. Traditionally this test has consisted of approximately ten steps each of 20 min duration. However, steps of shorter duration (e.g. 1 min) are increasingly being utilized to capture acceleration ability or burst swimming performance. Regardless of step size, swimming tests can be repeated over time to gauge individual variation and recovery ability. Endpoints related to swimming such as measures of metabolic rate, fin use, ventilation rate, and of behavior, such as the distance between schooling fish, are often included before, during and after swimming tests. Given the diversity of fish species, the number of unexplored research questions, and the importance of many species to global ecology and economic health, studies of fish swimming performance will remain popular and invaluable for the foreseeable future.

  1. Keila Tervisekeskus. Ujula = Keila Health Club. Swimming Pool / Ain Padrik

    Index Scriptorium Estoniae

    Padrik, Ain, 1947-

    2001-01-01

    Projekteerija: Arhitektuuribüroo Künnapu & Padrik. Arhitektid Ain Padrik ja Kristi Alamaa, sisearhitekt Sirje Männik. Konstruktsioonid: Jaan Laks, A-Grupp. Ujulas on võistlus- ja lastebassein, suvel on avatud välibassein. 5 ill.: I korruse plaan, ristlõige, vaated

  2. Sewage sludges disinfection

    International Nuclear Information System (INIS)

    Alexandre, D.

    1977-01-01

    There is an hygienic risk in using biological sewage sludges for agriculture. Systematic analysis carried out on sludges samples obtained from purification plants in East and South part of France, show the almost uniform presence of pathogenic microorganisms. Some of it survive more than 9 months after soil application. Conventional process for disinfection: liming and heat are not suitable for agricultural use. On the other hand, irradiation involves no modification in structure and composition of sludges. Radiation doses required for disinfection vary according to microorganisms. If some of them are eliminated with rather light doses (200 krad) mycobacteria, viruses and eggs of worms resist to more important doses. Security dose is estimated around 1000 krad

  3. 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.

  4. Improving Pool Fencing Legislation in Queensland, Australia: Attitudes and Impact on Child Drowning Fatalities

    Directory of Open Access Journals (Sweden)

    Richard C. Franklin

    2017-11-01

    Full Text Available Four-sided, non-climbable pool fencing is an effective strategy for preventing children from drowning in home swimming pools. In 2009, the Queensland Government introduced legislation to improve the effectiveness of pool fencing. This study explores community attitudes towards the effectiveness of these legislative changes and examines child (<5 years drowning deaths in pools. Data from the 2011 Queensland Computer-Assisted Telephone Interviewing (CATI Social Survey include results from questions related to pool ownership and pool fencing legislation. Fatal child drowning cases between 1 January 2005 and 31 December 2015 were sourced from coronial data. Of the 1263 respondents, 26/100 households had a pool. A total of 58% believed tightening legislation would be effective in reducing child drowning deaths. Pool owners were more likely to doubt the effectiveness of legislation (p < 0.001 when compared to non-pool owners. Perceptions of effectiveness did not differ by presence of children under the age of five. There were 46 children who drowned in Queensland home pools (7.8/100,000 pools with children residing in the residence/annum between 2005 and 2015. While pool owners were less likely to think that tightening the legislation would be effective, the number of children drowning in home swimming pools declined over the study period. Drowning prevention agencies have more work to do to ensure that the most vulnerable (young children in houses with swimming pools are protected.

  5. A review on wastewater disinfection

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Amin

    2013-01-01

    Full Text Available Changes in regulations and development of new technologies have affected the selection of alternative for treated wastewater disinfection. Disinfection is the last barrier of wastewater reclamation process to protect ecosystem safety and human health. Driving forces include water scarcity and drinking water supply, irrigation, rapid industrialization, using reclaimed water, source protection, overpopulation, and environmental protection. The safe operation of water reuse depends on effluent disinfection. Understanding the differences in inactivation mechanisms is critical to identify rate-limiting steps involved in the inactivation process as well as to develop more effective disinfection strategies. Disinfection byproducts discharged from wastewater treatment plants may impair aquatic ecosystems and downstream drinking-water quality. Numerous inorganic and organic micropollutants can undergo reactions with disinfectants. Therefore, to mitigate the adverse effects and also to enhance that efficiency, the use of alternative oxidation/disinfection systems should be evaluated as possible alternative to chlorine. This review gives a summary of the traditional, innovative, and combined disinfection alternatives and also disinfection byproducts for effluent of municipal wastewater treatment plants.

  6. Stirring by swimming bodies

    Energy Technology Data Exchange (ETDEWEB)

    Thiffeault, Jean-Luc, E-mail: jeanluc@math.wisc.ed [Department of Mathematics, University of Wisconsin - Madison, 480 Lincoln Dr., Madison, WI 53706 (United States); Institute for Mathematics and Applications, University of Minnesota - Twin Cities, 207 Church Street S.E., Minneapolis, MN 55455 (United States); Childress, Stephen [Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, NY 10012 (United States)

    2010-07-26

    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.

  7. Investigación de un brote respiratorio agudo por exposición a cloro gas en una piscina pública Investigation of an outbreak of acute respiratory illness due to exposure to chlorine gas in a public swimming pool

    Directory of Open Access Journals (Sweden)

    Diego Almagro Nievas

    2008-06-01

    Full Text Available Se diseñó un estudio de casos y controles para investigar el accidente químico ocurrido en una piscina pública en el verano de 2005 y describir los factores ambientales responsables, analizar el efecto del cloro gas y valorar la evolución clínica y funcional del aparato respiratorio. Las intervenciones fueron las siguientes: inspecciones ambientales, encuesta epidemiológica (variables sociodemográficas, ubicación en el momento del accidente, olor percibido y seguimiento clínico y espirométrico de la función respiratoria. Se encuestaron 65 casos y 48 controles. El suceso se produjo al mezclar accidentalmente ácido clorhídrico e hipoclorito sódico, lo que generó cloro gas. Los síntomas predominantes fueron tos y disnea. El riesgo de enfermar en niños era 10 veces mayor si tenían una enfermedad respiratoria previa y 4 veces superior si estaban a una distancia inferior a 40 m del lugar del accidente. Todos los casos evolucionaron hacia la curación, excepto uno que tenía antecedentes asmáticos.A case-control study was designed to investigate a chemical accident that occurred in a swimming-pool in the summer of 2005. The aim was to describe the environmental factors involved in the accident, to assess the effect of chlorine gas on the respiratory system, and to perform a clinical and spirometric follow-up. The following interventions were carried out: environmental inspection, epidemiologic survey (including sociodemographic variables, location at the time of the accident, perception of an abnormal smell, and clinical and spirometric outcomes to assess respiratory function. Sixty-five cases and 48 controls were identified and interviewed. The accident was produced by accidental admixture of hydrochloric acid with sodium hypochlorite resulting in chlorine gas release. The main clinical symptoms were dyspnea and cough. The risk of becoming ill was 10-fold higher in children with a previous lung disease and was 4-fold higher when

  8. Sanitizers and Disinfectants Guide. Revised

    Science.gov (United States)

    Healthy Schools Network, Inc., 2012

    2012-01-01

    Sanitizers and disinfectants can play an important role in protecting public health. They are designed to kill "pests," including infectious germs and other microorganisms such as bacteria, viruses, and fungi. Unfortunately, sanitizers and disinfectants also contain chemicals that are "pesticides." Exposure to persistent toxic…

  9. Determination of the solids retainment effectiveness of disposable swim diapers.

    Science.gov (United States)

    Maas, Richard P; Patch, Steven C; Berkowitz, Jacob F; Johnson, Holly D

    2004-06-01

    In light of recent and increasing incidences of pathogenic E. coli outbreaks at public bathing facilities attributable to non-toilet-trained infants and toddlers, many such facilities are restricting water contact for this age group. A number of manufacturers are now offering disposable "swim diapers," which claim to effectively retain fecal material under typical pool play conditions. The study reported here examined the solids retention effectiveness of three major brands of swim diapers as well as of conventional disposable diapers, under simulated water play conditions. Swim diapers of all three brands exhibited an approximately equal fine-solids retention capability of about 98 to 99 percent over 30 minutes of water immersion activity. Conventional disposable diapers invariably fell down or came apart during the experiments, resulting in very limited solids retention. This study indicates that commercially available swim diapers represent a vast improvement in reducing the potential for fecal material release in public pool facilities, but that some release will still generally occur with these products.

  10. Hospital hydrotherapy pools treated with ultra violet light: bad bacteriological quality and presence of thermophilic Naegleria.

    OpenAIRE

    De Jonckheere, J. F.

    1982-01-01

    The microbiological quality of eight halogenated and two u.v.-treated hydrotherapy pools in hospitals was investigated. The microbiological quality of halogenated hydrotherapy pools was comparable to halogenated public swimming pools, although in some Pseudomonas aeruginosa and faecal pollution indicators were more frequent due to bad management. On the other hand u.v.-treated hydrotherapy pools had very bad microbiological quality. Apart from faecal pollution indicators, P. aeruginosa was pr...

  11. 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...

  12. Sand swimming lizard: sandfish

    OpenAIRE

    Maladen, Ryan D.; Ding, Yang; Kamor, Adam; Goldman, Daniel I.

    2009-01-01

    We use high-speed x-ray imaging to reveal how a small (~10cm) desert dwelling lizard, the sandfish (Scincus scincus), swims within a granular medium [1]. On the surface, the lizard uses a standard diagonal gait, but once below the surface, the organism no longer uses limbs for propulsion. Instead it propagates a large amplitude single period sinusoidal traveling wave down its body and tail to propel itself at speeds up to ~1.5 body-length/sec. Motivated by these experiments we study a numeric...

  13. Solar water disinfection

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R. [Universal Recycled Water Systems, Orlando, FL (United States); Collier, R. [Enerscope, Inc., Merritt Island, FL (United States)

    1996-11-01

    Non-potable drinking water is a major problem for much of the world`s population. It has been estimated that from 15 to 20 million children under the age of 5 die from diarrheal conditions brought on by infected drinking water every year. This is equivalent to a fully-loaded DC-10 crashing every ten minutes of every day, 365 days a year. Heat is one of the most effective methods of disinfecting drinking water. Using conventional means of heating water (heating on an open-flamed stove) results in an extremely energy-intensive process. The main obstacle is that for areas of the world where potable water is a problem, fuel supplies are either too expensive, not available, or the source of devastating environmental problems (deforestation). The apparatus described is a solar-powered water disinfection device that can overcome most if not all of the barriers that presently limit technological solutions to drinking water problems. It uses a parabolic trough solar concentrator with a receiver tube that is also a counterflow heat exchanger. The system is totally self-contained utilizing a photovoltaic-powered water pump, and a standard automotive thermostat for water flow control. The system is designed for simplicity, reliability and the incorporation of technology readily accessible in most areas of the world. Experiments at the Florida Solar Energy Center have demonstrated up to 2,500 liters of safe drinking water per day with 28 square meters of solar concentrator.

  14. Influence of mobile games on the process of teaching of students that can not swim

    Directory of Open Access Journals (Sweden)

    Strelnykov G.L.

    2012-02-01

    Full Text Available Considered direction in teaching of students to swimming in terms 25 meter pool. 30 students took part in an experiment. The place of mobile games in the process of teaching of novices is certain. Information of results of testing of level of physical preparedness of students is presented. Positive influence of mobile games on the process of mastering of skills of swimming and co-operations on water is marked. Forms and methods of mastering of skills and conduct in water are offered. The motive mode and forms of organization of educational process of not able to swim students is recommended.

  15. Hawaii ESI: POOLS (Anchialine Pool Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for anchialine pools in Hawaii. Anchialine pools are small, relatively shallow coastal ponds that occur...

  16. Ultraviolet disinfection of potable water

    International Nuclear Information System (INIS)

    Wolfe, R.L.

    1990-01-01

    Because of upcoming surface and groundwater regulations regarding the control of microbiological and chemical contaminants, there is a need to evaluate the feasibility and effectiveness of ultraviolet (UV) radiation for primary disinfection of potable water supplies. Data is presented on microbicidal wavelengths of UV and distribution of energy output for low and medium-pressure arc lamps. Both systems were found to perform equally well for inactivating microorganisms, but each had distinct advantages in different applications. Approximate dosages for 90% inactivation of selected microorganisms by UV is presented in a table. Cost analysis for disinfection is presented in two tables as well as the advantages and disadvantages of UV disinfection

  17. 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...

  18. Baby swimming and respiratory health.

    Science.gov (United States)

    Nystad, Wenche; Håberg, Siri E; London, Stephanie J; Nafstad, Per; Magnus, Per

    2008-05-01

    To estimate the effect of baby swimming in the first 6 months of life on respiratory diseases from 6 to 18 months. We used data from The Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Health in children born between 1999 and 2005 followed from birth to the age of 18 months (n = 30,870). Health outcomes: lower respiratory tract infections (LRTI), wheeze and otitis media between 6 and 18 months of age. baby swimming at the age of 6 months. The effect of baby swimming was estimated by logistic regression analysis adjusting for potential confounders. About 25% of the children participated in baby swimming. The prevalence of LRTI was 13.3%, wheeze 40.0% and otitis media 30.4%. Children who were baby swimming were not more likely to have LRTI, to wheeze or to have otitis media. However, children with atopic mothers who attended baby swimming had an increased risk of wheeze, adjusted odds ratios (aOR) 1.24 (95% CI 1.11, 1.39), but not LRTI or otitis media. This was also the case for children without respiratory diseases before 6 months aOR 1.08 (95%CI 1.02-1.15). Baby swimming may be related to later wheeze. However, these findings warrant further investigation.

  19. Disposable swim diaper retention of Cryptosporidium-sized particles on human subjects in a recreational water setting.

    Science.gov (United States)

    Amburgey, James E; Anderson, J Brian

    2011-12-01

    Cryptosporidium is a chlorine-resistant protozoan parasite responsible for the majority of waterborne disease outbreaks in recreational water venues in the USA. Swim diapers are commonly used by diaper-aged children participating in aquatic activities. This research was intended to evaluate disposable swim diapers for retaining 5-μm diameter polystyrene microspheres, which were used as non-infectious surrogates for Cryptosporidium oocysts. A hot tub recirculating water without a filter was used for this research. The microsphere concentration in the water was monitored at regular intervals following introduction of microspheres inside of a swim diaper while a human subject undertook normal swim/play activities. Microsphere concentrations in the bulk water showed that the majority (50-97%) of Cryptosporidium-sized particles were released from the swim diaper within 1 to 5 min regardless of the swim diaper type or configuration. After only 10 min of play, 77-100% of the microspheres had been released from all swim diapers tested. This research suggests that the swim diapers commonly used by diaper-aged children in swimming pools and other aquatic activities are of limited value in retaining Cryptosporidium-sized particles. Improved swim diaper solutions are necessary to efficiently retain pathogens and effectively safeguard public health in recreational water venues.

  20. [Management of infectious risk associated with therapeutic pools].

    Science.gov (United States)

    Chapuis, C; Gardes, S; Tasseau, F

    2004-06-01

    There is no specific legislation concerning pools and others medical hydrotherapy equipments relating hygiene and security rules. For this reason, the hydrotherapy pools use the public swimming pools legislation. This article is based on literature review (database Medline and Embase--manual research). This article offers a review of pool associated infections along with the description of the measures designed to minimise the possible transmission of infection during hydrotherapy activities such as: Technical measures: pool and premises conception, water treatments, feed tanks, air quality. Hygiene rules for patients and hospital staff and pathologies which are contra-indications to hydrotherapy activities. Microbiological and physico-chemical monitoring. The infectious risk remains low with therapeutic pools. However, the development of specific legislation and surveillance should be enhanced. All these measures are part of the quality assurance program that must be implemented to control the safety of these installations.

  1. A review on wastewater disinfection

    OpenAIRE

    Mohammad Mehdi Amin; Hassan Hashemi; Amir Mohammadi Bovini; Yung Tse Hung

    2013-01-01

    Changes in regulations and development of new technologies have affected the selection of alternative for treated wastewater disinfection. Disinfection is the last barrier of wastewater reclamation process to protect ecosystem safety and human health. Driving forces include water scarcity and drinking water supply, irrigation, rapid industrialization, using reclaimed water, source protection, overpopulation, and environmental protection. The safe operation of water reuse depends on effluent d...

  2. Examining self-training procedures in leisure swimming.

    Science.gov (United States)

    J Potdevin, Francois; Normani, Clement; Pelayo, Patrick

    2013-01-01

    their session even if they have a good skill level. This suggests to improve health strategy education and swimming pool environment.

  3. 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...

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

    African Journals Online (AJOL)

    STORAGESEVER

    2009-04-06

    Apr 6, 2009 ... 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 ...

  5. 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 ...

  6. Non-electric applications of pool-type nuclear reactors

    International Nuclear Information System (INIS)

    Adamov, E.O.; Cherkashov, Yu.M.; Romenkov, A.A.

    1997-01-01

    This paper recommends the use of pool-type light water reactors for thermal energy production. Safety and reliability of these reactors were already demonstrated to the public by the long-term operation of swimming pool research reactors. The paper presents the design experience of two projects: Apatity Underground Nuclear Heating Plant and Nuclear Sea-Water Desalination Plant. The simplicity of pool-type reactors, the ease of their manufacturing and maintenance make this type of a heat source attractive to the countries without a developed nuclear industry. (author). 6 figs, 1 tab

  7. Healthy Swimming/Recreational Water

    Science.gov (United States)

    ... Model Aquatic Health Code (MAHC) Featured Partners Healthy Water Sites Healthy Water Drinking Water Healthy Swimming Global WASH Other Uses of Water WASH-related Emergencies & Outbreaks Water, Sanitation, & Environmentally-related ...

  8. 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.

  9. 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.

  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. Disinfection of the Peritoneal Dialysis Bag Medication Port: Comparison of Disinfectant Agent and Disinfection Time.

    Science.gov (United States)

    Conti, Adriana; Katzap, Roberta Monteiro; Poli-de-Figueiredo, Carlos Eduardo; Pagnussatti, Vany; Figueiredo, Ana Elizabeth

    2017-07-13

    To compare different disinfection techniques for the peritoneal dialysis bag medication port (MP). An experimental study was conducted testing different cleaning agents (70% alcohol vs 2% chlorhexidine) and time periods (5, 10 and 60 seconds) for disinfection of the MP. Five microorganisms (S. aureus, E.coli, A. baumannii and C. parapsilosis, CNS) were prepared for use as contaminants of the MP. MP were incubated in Tryptic soy broth at 36 °C for 24 h, after which, they were seeded on a Biomérieux® blood agar plate and incubated for 24 h at 36 °C. 300 peritoneal dialysis bags were analyzed regarding the time expose to the disinfectant showed a statistically significant difference in the number of culture positive (7/100) p = 0.001; Gram positive (6/100) p = 0.006 for five seconds, one positive culture and turbid bag with ten seconds, while friction for 60 seconds showed all negative results. The comparison between disinfectant, alcohol or chlorhexidine, 150 bag in each group, showed that the ones disinfected with alcohol had 5 turbid bags, 8 positive cultures and 7 germs identified, while all bags disinfected with chlorhexidine were negative for all parameters, with a difference statistically significant (p = 0.004). Our results suggest that the MP should be scrubbed with 2% chlorhexidine for at least 5 seconds; if alcohol 70% is used the length of friction should not be inferior to 10 seconds. This article is protected by copyright. All rights reserved.

  12. 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...... 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....

  13. 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'.

  14. 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.

  15. Influence of pre-school swimming on level of swimming abilities of early schol age children

    OpenAIRE

    Velová, Lenka

    2011-01-01

    My thesis paper is focused on children swimming from their birth to early school age. The pivotal part of the paper is the comparison of swimming abilities between primary school children who have passed pre-school swimming training and those who have had no training at all. Theoretical framework of the paper is then focused on general swimming theory, characteristics of children's evolutionary stages within the context of swimming and definition of basic swimming skills.

  16. Socioeconomic environment, availability of sports facilities, and jogging, swimming and gym use.

    Science.gov (United States)

    Pascual, Cruz; Regidor, Enrique; Martínez, David; Elisa Calle, M; Domínguez, Vicente

    2009-06-01

    The aim of the study was to evaluate the association of the availability of sports facilities and socioeconomic environment with jogging, swimming and gym use in Spain. The indicators of availability of sports facilities were the number of swimming pools and the number of gyms per 10,000 population. The indicators of socioeconomic environment were average provincial income and provincial unemployment rate. The number of sports facilities was not related with either swimming or gym use and the indicators of socioeconomic environment were not associated with swimming in either sex, or with gym use in men. The findings of this study do not support the hypotheses proposed in previous investigations to explain the consistent relation between socioeconomic environment and lack of physical activity.

  17. 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

  18. Variability in Measurement of Swimming Forces: A Meta-Analysis of Passive and Active Drag

    Science.gov (United States)

    Havriluk, Rod

    2007-01-01

    An analysis was conducted to identify sources of true and error variance in measuring swimming drag force to draw valid conclusions about performance factor effects. Passive drag studies were grouped according to methodological differences: tow line in pool, tow line in flume, and carriage in tow tank. Active drag studies were grouped according to…

  19. 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

  20. Can pulsed xenon ultraviolet light systems disinfect aerobic bacteria in the absence of manual disinfection?

    Science.gov (United States)

    Jinadatha, Chetan; Villamaria, Frank C; Ganachari-Mallappa, Nagaraja; Brown, Donna S; Liao, I-Chia; Stock, Eileen M; Copeland, Laurel A; Zeber, John E

    2015-04-01

    Whereas pulsed xenon-based ultraviolet light no-touch disinfection systems are being increasingly used for room disinfection after patient discharge with manual cleaning, their effectiveness in the absence of manual disinfection has not been previously evaluated. Our study indicates that pulsed xenon-based ultraviolet light systems effectively reduce aerobic bacteria in the absence of manual disinfection. These data are important for hospitals planning to adopt this technology as adjunct to routine manual disinfection. Published by Elsevier Inc.

  1. Ultrasound transducer disinfection in emergency medicine practice

    Directory of Open Access Journals (Sweden)

    Riley Hoyer

    2016-04-01

    Full Text Available Abstract Background External ultrasound transducer disinfection is common practice in medicine. Unfortunately, clinically significant organisms, such as methicillin-resistant Staphylococcus aureus (MRSA, Pseudomonas aeruginosa, and Klebsiella pneumonia spread throughout healthcare facilities via direct contact despite disinfection protocols. Ultrasound transducers and coupling gel provide potential vectors for pathogen transmission, especially in immunocompromised and high-risk patient populations. Our objective was to conduct a survey to investigate the variety of cleaning solutions or sanitary wipes used and evaluate current standard practice for transducer disinfection across emergency medicine training programs in the United States. Findings Eighty-three academic emergency medicine programs participated in this study. Eighty-seven percent (95 % CI 80–94 % of responding programs do not have a mandated protocol or standard contact time for transducer disinfection. Ninety percent (95 % CI 84–96 % of institutions use disinfectant solution or disinfectant wipes, as the standard of practice, to cleanse ultrasound transducers after every use. Conclusions Currently, there is a great deal of variability with regard to non-endocavitary transducer disinfection protocols that seems to stem from the vast number of disinfectant products and ultrasound manufacturer disparate recommendations. In order to mitigate risk to patients and reduce health care costs linked to nosocomial infections; healthcare providers, ultrasound companies, and disinfectant manufacturers must develop a universal use disinfectant and a standard protocol for ultrasound device disinfection for noncritical device disinfection in the emergency department.

  2. Ultrasound transducer disinfection in emergency medicine practice.

    Science.gov (United States)

    Hoyer, Riley; Adhikari, Srikar; Amini, Richard

    2016-01-01

    External ultrasound transducer disinfection is common practice in medicine. Unfortunately, clinically significant organisms, such as methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Klebsiella pneumonia spread throughout healthcare facilities via direct contact despite disinfection protocols. Ultrasound transducers and coupling gel provide potential vectors for pathogen transmission, especially in immunocompromised and high-risk patient populations. Our objective was to conduct a survey to investigate the variety of cleaning solutions or sanitary wipes used and evaluate current standard practice for transducer disinfection across emergency medicine training programs in the United States. Eighty-three academic emergency medicine programs participated in this study. Eighty-seven percent (95 % CI 80-94 %) of responding programs do not have a mandated protocol or standard contact time for transducer disinfection. Ninety percent (95 % CI 84-96 %) of institutions use disinfectant solution or disinfectant wipes, as the standard of practice, to cleanse ultrasound transducers after every use. Currently, there is a great deal of variability with regard to non-endocavitary transducer disinfection protocols that seems to stem from the vast number of disinfectant products and ultrasound manufacturer disparate recommendations. In order to mitigate risk to patients and reduce health care costs linked to nosocomial infections; healthcare providers, ultrasound companies, and disinfectant manufacturers must develop a universal use disinfectant and a standard protocol for ultrasound device disinfection for noncritical device disinfection in the emergency department.

  3. Interaction between some disinfectants and Tcsup(99m)-radiopharmaceuticals

    International Nuclear Information System (INIS)

    Verbruggen, A.; Cleynhens, B.; Hoogmartens, M.; De Roo, M.

    1985-01-01

    Contamination of Tcsup(99m) sulphur colloid with small amounts of iodinated antiseptics has been described to result in the formation of free pertechnetate and excessive blood-pool activity upon injection. As far as we know similar or other interactions have not been reported for disinfectants that are effective by another mechanism than oxidizing activity. The present study has been set up to investigate the effect of small amounts of a wide variety of commonly available antiseptics on the radiochemical and biological behaviour of different Tcsup(99m) labelled radiopharmaceuticals. (Auth.)

  4. 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.

  5. PACING DEVICE FOR SWIMMING. MECHANICAL CONSTRUCTION OF CONSTANT SPEED

    Directory of Open Access Journals (Sweden)

    MESSINIS S.

    2010-04-01

    Full Text Available The pace in swimming is very important because it allows swimmers to allocate their forces accordingly, and therefore a distance to travel as quickly as possible. The training pace at different swimmingspeeds and combinations thereof, is an important part of training before the competitions.The definition and maintenance of the stable and swimmer specific speed is difficult to achieve and requires considerable effort and experience. To determine the desired rate of accuracy by the researchers and their coaches used till now, various audio and visual media.However, some of these institutions did not very accurately measure the rate and not all styles of swimming, while other aspects affect the proper swimming. In this construction, a key objective is to solve the problems occurring in the previous constructions, the modern technological development of them and the adaption of the specificities of different swimming styles.This device consists of an electro 3 / 8 of the horse, a flange, a single inverter from 3 / 8 to ½ of the horse, pulleys with taper Bush, flange axle, pulleys, platforms and a 52 meters cable. The assembly and operation is as follows: At the edge of the pool next to the platform is placed the base of pulleys, the electro setis connected to the inverter and the axle flange.Precisely opposite is positioned the other base. Along the pool «moves» the cable that connects the two bases, located 150 cm above the water. A fixed point on the cable is marked with paint in order to be visible to the swimmer during backstroke swimming while for other styles we adapt a lamination at the cable vertically inthe pool, above the surface a sheet of 15 cm which is painted with strong color that is visible from the athlete and will precede him. Setting the speed with inverter it starts from one end of the tank leading to the other, doing a circular motion.The swimmer is required to follow the marked point of the cable in the backstroke or

  6. The shoulder in competitive swimming.

    Science.gov (United States)

    Richardson, A B; Jobe, F W; Collins, H R

    1980-01-01

    Shoulder pain is the most common orthopaedic problem in competitive swimming. In a group of 137 of this country's best swimmers, 58 had had symptoms of "swimmer's shoulder." Population characteristics of this group indicated that symptoms increased with the caliber of the athlete, were slightly more common in men, and were related to sprint rather than distance swimming. The use of hand-paddle training exacerbated symptoms, which were more common during the early and middle season. Consideration of shoulder mechanics in swimming reveals that freestyle, butterfly, and backstroke require similar motions; a swimmer using any of these strokes is susceptible to developing shoulder pain. Swimmer's shoulder represents chronic irritation of the humeral head and rotator cuff on the coracoacromial arch during abduction of the shoulder, the so-called impingement syndrome. Treatment included stretching, rest, ice therapy, oral antiinflammatory agents, judicious use of injectable steroids, and surgery as a last resort.

  7. 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.

  8. 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.

  9. 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

  10. Validation of GPS and accelerometer technology in swimming.

    Science.gov (United States)

    Beanland, Emma; Main, Luana C; Aisbett, Brad; Gastin, Paul; Netto, Kevin

    2014-03-01

    To evaluate the validity of an integrated accelerometer and Global Positioning System (GPS) device to quantify swimming kinematics variables in swimming. Criterion validation study. Twenty-one sub-elite swimmers completed three 100 m efforts (one butterfly, breaststroke and freestyle) in an outdoor 50 m Olympic pool. A GPS device with an integrated tri-axial accelerometer was used to obtain mid-pool velocity and stroke count of each effort. This data was compared to velocity and stroke count data obtained from concurrently recorded digital video of the performance. A strong relationship was detected between the accelerometer stroke count and the video criterion measure for both breaststroke (r>0.98) and butterfly (r>0.99). Also, no significant differences were detected between the GPS velocity and video obtained velocity for both freestyle and breaststroke. There was a significant difference between the GPS velocity and criterion measure for butterfly. Acceptable standard error and 95% limits of agreement were obtained for freestyle (0.13 m s(-1), 0.36 m s(-1)) and breaststroke (0.12 m s(-1), 0.33 m s(-1)) compared to butterfly (0.18 m s(-1), 0.50 m s(-1)). Relative error measurements ranged between 10.2 and 13.4% across the three strokes. The integrated accelerometer and GPS device offers a valid and accurate tool for stroke count quantification in breaststroke and butterfly as well as measuring mid-pool swimming velocity in freestyle and breaststroke. The application of GPS technology in the outdoor training environment suggests advantageous practical benefits for swimmers, coaches and sports scientists. Copyright © 2013 Sports Medicine Australia. All rights reserved.

  11. 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...

  12. Less skin irritation from alcohol-based disinfectant than from detergent used for hand disinfection

    DEFF Research Database (Denmark)

    Pedersen, L K; Held, E; Johansen, J D

    2005-01-01

    BACKGROUND: The benefit of alcohol-based disinfectant used on normal skin has been debated. OBJECTIVES: The objective of the present study was to compare the effects of repeated exposure to an alcohol-based disinfectant, a detergent and an alcohol-based disinfectant/detergent alternately for 10...... days, including noninvasive measurements in the evaluation. Skin reactivity in irritated skin after a 4-week interval was also evaluated. MATERIALS AND METHODS: Detergent, disinfectant and alternate disinfectant and detergent were applied twice daily every 10 min for 1 h to the ventral upper arms......: On day 5 the detergent caused a higher visual score than either disinfectant applied alone or alternate disinfectant and detergent, P detergent and alternate disinfectant and detergent caused a higher score than disinfectant, P detergent...

  13. Modelling swimming hydrodynamics to enhance performance

    OpenAIRE

    Marinho, D.A.; Rouboa, A.; Barbosa, Tiago M.; Silva, A.J.

    2010-01-01

    Swimming assessment is one of the most complex but outstanding and fascinating topics in biomechanics. Computational fluid dynamics (CFD) methodology is one of the different methods that have been applied in swimming research to observe and understand water movements around the human body and its application to improve swimming performance. CFD has been applied attempting to understand deeply the biomechanical basis of swimming. Several studies have been conducted willing to analy...

  14. 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...

  15. 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...

  16. 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...

  17. Energetics of swimming of schooling fish

    DEFF Research Database (Denmark)

    Steffensen, John Fleng

    2012-01-01

    schools. Oxygen consumption of swimming fish increases exponentially or as a power function with respect to swimming speed, and hence the decrease in oxygen saturation through the school is related to the swimming speed of the school. A model describing the oxygen saturation in a fish school from front...

  18. 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 ...

  19. The hydrodynamics of swimming microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Lauga, Eric [Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093-0411 (United States); Powers, Thomas R [Division of Engineering, Brown University, Providence, RI 02912-9104 (United States)], E-mail: elauga@ucsd.edu, E-mail: Thomas_Powers@brown.edu

    2009-09-15

    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.

  20. 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.

  1. Sports Medicine Meets Synchronized Swimming.

    Science.gov (United States)

    Wenz, Betty J.; And Others

    This collection of articles contains information about synchronized swimming. Topics covered include general physiology and cardiovascular conditioning, flexibility exercises, body composition, strength training, nutrition, coach-athlete relationships, coping with competition stress and performance anxiety, and eye care. Chapters are included on…

  2. Fluid Mechanics of Fish Swimming

    Indian Academy of Sciences (India)

    user

    shark). Redrawn from Review of Fish. Swimming Modes for Aquatic. Locomotion, IEEE Journal of. Oceanic Engineering, Vol.24,. No.2, pp. 237–252, 1999, D M. Lane, M Sfakiotakis and J B C. Davies, Heriot-Watt University. undulatory → oscillatory caudaltail¯n (B C F ) m otions are know n collectively as. B C F sw im m ers.

  3. 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.

  4. 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:

  5. 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.

  6. Fluid Mechanics of Fish Swimming

    Indian Academy of Sciences (India)

    user

    forces generated by their °apping tails. A nguilliform sw im m .... In natural systems, like a human walking or a ¯sh swimming, there is always unsteadiness. ... (L) mainly from the wings balances the weight (W). b) For the fish shown here the thrust is mainly from the flapping tail. Lift from fins and buoyancy (FB ) bal- ance the ...

  7. 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…

  8. Influence of mobile games on the process of teaching of students that can not swim

    OpenAIRE

    Strelnykov G.L.; Lozgachov G.V.; Strelnykova Y.Y.

    2012-01-01

    Considered direction in teaching of students to swimming in terms 25 meter pool. 30 students took part in an experiment. The place of mobile games in the process of teaching of novices is certain. Information of results of testing of level of physical preparedness of students is presented. Positive influence of mobile games on the process of mastering of skills of swimming and co-operations on water is marked. Forms and methods of mastering of skills and conduct in water are offered. The moti...

  9. 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.

  10. Biomechanical analysis of backstroke swimming starts.

    Science.gov (United States)

    de Jesus, K; de Jesus, K; Figueiredo, P; Gonçalves, P; Pereira, S; Vilas-Boas, J P; Fernandes, R J

    2011-07-01

    The relationships between the start time and kinematic, kinetic and electromyographic data were examined in order to establish the common features of an effective backstroke swimming start. Complementarily, different starting positions were analysed to identify the parameters that account for the fastest backstroke start time under different constraints. 6 high-level swimmers performed 4×15 m maximal trials of each start variants with different feet position: parallel and entirely submerged (BSFI) and above water surface (BSFE), being monitored with synchronized dual-media image, underwater platform plus handgrip with a load cell, and eletromyographic signal of RECTUS FEMORIS and GASTROCNEMIUS MEDIALIS. Mean and SD values of start time for BSFI and BSFE were 2.03 ± 0.19 and 2.14 ± 0.36 s, respectively. In both starts, high associations (r > =0.75, p < 0.001) were observed between start time and centre of mass resultant average velocity at glide phase and horizontal impulse at take-off for BSFI, and centre of mass horizontal position at the start signal for BSFE. It was concluded that the greater impulse during the take-off and its transformation into a fast underwater movement are determinant to decrease the start time at BSFI. Regarding BSFE, a greater centre of mass pool-wall approximation might imply a flatter take-off angle, compromising underwater velocity and starting performance. © Georg Thieme Verlag KG Stuttgart · New York.

  11. Zinc oxide nanoparticles for water disinfection

    Directory of Open Access Journals (Sweden)

    Emelita Asuncion S. Dimapilis

    2018-03-01

    Full Text Available The world faces a growing challenge for adequate clean water due to threats coming from increasing demand and decreasing supply. Although there are existing technologies for water disinfection, their limitations, particularly the formation of disinfection-by-products, have led to researches on alternative methods. Zinc oxide, an essential chemical in the rubber and pharmaceutical industries, has attracted interest as antimicrobial agent. In nanoscale, zinc oxide has shown antimicrobial properties which make its potential great for various applications. This review discusses the synthesis of zinc oxide with focus on precipitation method, its antimicrobial property and the factors affecting it, disinfection mechanisms, and the potential application to water disinfection.

  12. Nutritional recommendations for synchronized swimming.

    Science.gov (United States)

    Robertson, Sherry; Benardot, Dan; Mountjoy, Margo

    2014-08-01

    The sport of synchronized swimming is unique, because it combines speed, power, and endurance with precise synchronized movements and high-risk acrobatic maneuvers. Athletes must train and compete while spending a great amount of time underwater, upside down, and without the luxury of easily available oxygen. This review assesses the scientific evidence with respect to the physiological demands, energy expenditure, and body composition in these athletes. The role of appropriate energy requirements and guidelines for carbohydrate, protein, fat, and micronutrients for elite synchronized swimmers are reviewed. Because of the aesthetic nature of the sport, which prioritizes leanness, the risks of energy and macronutrient deficiencies are of significant concern. Relative Energy Deficiency in Sport and disordered eating/eating disorders are also of concern for these female athletes. An approach to the healthy management of body composition in synchronized swimming is outlined. Synchronized swimmers should be encouraged to consume a well-balanced diet with sufficient energy to meet demands and to time the intake of carbohydrate, protein, and fat to optimize performance and body composition. Micronutrients of concern for this female athlete population include iron, calcium, and vitamin D. This article reviews the physiological demands of synchronized swimming and makes nutritional recommendations for recovery, training, and competition to help optimize athletic performance and to reduce risks for weight-related medical issues that are of particular concern for elite synchronized swimmers.

  13. 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.

  14. Collaborative Car Pooling System

    OpenAIRE

    João Ferreira; Paulo Trigo; Porfírio Filipe

    2009-01-01

    This paper describes the architecture for a collaborative Car Pooling System based on a credits mechanism to motivate the cooperation among users. Users can spend the accumulated credits on parking facilities. For this, we propose a business model to support the collaboration between a car pooling system and parking facilities. The Portuguese Lisbon-s Metropolitan area is used as application scenario.

  15. Hospital hydrotherapy pools treated with ultra violet light: bad bacteriological quality and presence of thermophilic Naegleria.

    Science.gov (United States)

    De Jonckheere, J F

    1982-04-01

    The microbiological quality of eight halogenated and two u.v.-treated hydrotherapy pools in hospitals was investigated. The microbiological quality of halogenated hydrotherapy pools was comparable to halogenated public swimming pools, although in some Pseudomonas aeruginosa and faecal pollution indicators were more frequent due to bad management. On the other hand u.v.-treated hydrotherapy pools had very bad microbiological quality. Apart from faecal pollution indicators, P. aeruginosa was present in very high numbers. Halogenated hydrotherapy pools were not highly contaminated with amoebae, and Naegleria spp. were never detected. On the other hand u.v.-treated pools contained very high numbers of thermophilic Naegleria. The Naegleria isolated were identified as N. lovaniensis, a species commonly found in association with N. fowleri. Isoenzyme analysis showed a different type of N. lovaniensis was present in each of two u.v.-treated pools.

  16. Hospital hydrotherapy pools treated with ultra violet light: bad bacteriological quality and presence of thermophilic Naegleria.

    Science.gov (United States)

    De Jonckheere, J. F.

    1982-01-01

    The microbiological quality of eight halogenated and two u.v.-treated hydrotherapy pools in hospitals was investigated. The microbiological quality of halogenated hydrotherapy pools was comparable to halogenated public swimming pools, although in some Pseudomonas aeruginosa and faecal pollution indicators were more frequent due to bad management. On the other hand u.v.-treated hydrotherapy pools had very bad microbiological quality. Apart from faecal pollution indicators, P. aeruginosa was present in very high numbers. Halogenated hydrotherapy pools were not highly contaminated with amoebae, and Naegleria spp. were never detected. On the other hand u.v.-treated pools contained very high numbers of thermophilic Naegleria. The Naegleria isolated were identified as N. lovaniensis, a species commonly found in association with N. fowleri. Isoenzyme analysis showed a different type of N. lovaniensis was present in each of two u.v.-treated pools. Images Plate 1 PMID:7061835

  17. The influence of explosive power on the performance of an elite swimmer in 25 and 50 metre pools

    Directory of Open Access Journals (Sweden)

    Simona Baumrtová

    2017-11-01

    Full Text Available Each swimming stroke, and each distance, requires a different approach to strength training. For sprinters in swimming the most essential part is explosive power. The goal of this case study was to find out how explosive training can influence the performance in both long course and short course meters swimming pools. This study was conducted with the cooperation of an elite swimmer over a time period of 6 years. Tests were performed twice a year (June and November during the years of 2010–2016. The Myotest device was used to measure countermovement jump height. Swimming performance was evaluated by FINA points in the swimmer’s three main disciplines. ANOVA, Cohen’s d and regression equation were used for statistical analysis. The results showed that explosive power does not influence performance in the 50m swimming pool (p = 0.25; r2 = 0.08. However the performance in the 25m pool is directly linked to the level of explosive power of the lower limbs (p < 0.001; r2 = 0.85. The results of the swimmer in the 25m pool are closely related to the level of explosive power of the lower limbs. Performance in the 50m pool might not be affected by level of lower limb power.

  18. Vortex re-capturing and kinematics in human underwater undulatory swimming.

    Science.gov (United States)

    Hochstein, Stefan; Blickhan, Reinhard

    2011-10-01

    To maximize swimming speed athletes copy fish undulatory swimming during the underwater period after start and turn. The anatomical limitations may lead to deviations and may enforce compensating strategies. This has been investigated by analyzing the kinematics of two national female swimmers while swimming in a still water pool. Additionally, the flow around and behind the swimmers was measured with the aid of time-resolved particle image velocimetry (TR-2D-PIV). As compared to fish, the swimmers used undulatory waves characterized by much higher Strouhal numbers but very similar amplitude distributions along the body and Froude efficiencies. Vortices generated in the region of strongly flexing joints are suitable to be used pedally to enhance propulsion (vortex re-capturing). Complementing studies using numerical and technical modeling will help us to probe the efficiency of observed mechanisms and further improvements of the human strategy. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. Kinematics of swimming garter snakes (Thamnophis sirtalis).

    Science.gov (United States)

    Munk, Yonatan

    2008-06-01

    We investigate the kinematics of swimming garter snakes (Thamnophis sirtalis) using a novel nonlinear regression-based digitization method to establish quantitative statistical support for non-constant wavelengths in the undulatory pattern exhibited by swimming snakes. We find that in swimming snakes, the growth of the amplitude of the propulsive wave head-to-tail is strongly correlated (p < 0.005) with the head-to-tail growth in the wavelength. We investigate correlations between kinematic parameters and steady swimming speed, and find a very strong positive correlation between swimming speed and undulation frequency. We furthermore find a statistically well-supported positive correlation between swimming speed and both the initial amplitude of the propulsive wave at the head and the degree of amplitude growth from head to tail.

  20. Enhanced active swimming in viscoelastic fluids

    OpenAIRE

    Riley, Emily E; Lauga, Eric Jean-Marie

    2014-01-01

    Swimming microorganisms often self propel in fluids with complex rheology. While past theoretical work indicates that fluid viscoelasticity should hinder their locomotion, recent experiments on waving swimmers suggest a possible non-Newtonian enhancement of locomotion. We suggest a physical mechanism, based on fluid-structure interaction, leading to swimming in a viscoelastic fluid at a higher speed than in a Newtonian one. Using Taylor's two-dimensional swimming sheet model, we solve for the...

  1. HYDRODINAMICS AND SWIMMING TEHNIQUE AS PARAMETERS FOR SUCCESSFULL SWIMMING AT THE AGE 10–12

    Directory of Open Access Journals (Sweden)

    Goran Dimitrić

    2008-08-01

    Full Text Available The aim of this study was to confirm that swimming technique and hydrodynamic parameters of a swimmer are relevant for successful swimming. Total of 63 boys, at the age of 10-12, participated in this research. There were 15 criterion morphology and specific motoric skills variables as well as one predictive variable derived from FINA points. We have concluded that hydrodynamic and swimming technique significantly contributes for successful swimming. These facts should use trainers as guidance for workout plan.

  2. 40 CFR 141.72 - Disinfection.

    Science.gov (United States)

    2010-07-01

    ... heterotrophic bacteria plate count (HPC) is measured; c=number of instances where the residual disinfectant... the residual disinfectant concentration is not measured but heterotrophic bacteria plate count (HPC... serves water to the public. Water in the distribution system with a heterotrophic bacteria concentration...

  3. Efficacy of Three Disinfectant Formulations against Multidrug ...

    African Journals Online (AJOL)

    The current increase in the prevalence of nosocomial infections within the hospital environment despite adequate cleaning and disinfection can be said to be due to the following: (i) ineffectiveness of the various disinfectant formulations used in infection control on the various hospital equipments and wards; (ii) development ...

  4. PDA: Pooled DNA analyzer

    Directory of Open Access Journals (Sweden)

    Lin Chin-Yu

    2006-04-01

    Full Text Available Abstract Background Association mapping using abundant single nucleotide polymorphisms is a powerful tool for identifying disease susceptibility genes for complex traits and exploring possible genetic diversity. Genotyping large numbers of SNPs individually is performed routinely but is cost prohibitive for large-scale genetic studies. DNA pooling is a reliable and cost-saving alternative genotyping method. However, no software has been developed for complete pooled-DNA analyses, including data standardization, allele frequency estimation, and single/multipoint DNA pooling association tests. This motivated the development of the software, 'PDA' (Pooled DNA Analyzer, to analyze pooled DNA data. Results We develop the software, PDA, for the analysis of pooled-DNA data. PDA is originally implemented with the MATLAB® language, but it can also be executed on a Windows system without installing the MATLAB®. PDA provides estimates of the coefficient of preferential amplification and allele frequency. PDA considers an extended single-point association test, which can compare allele frequencies between two DNA pools constructed under different experimental conditions. Moreover, PDA also provides novel chromosome-wide multipoint association tests based on p-value combinations and a sliding-window concept. This new multipoint testing procedure overcomes a computational bottleneck of conventional haplotype-oriented multipoint methods in DNA pooling analyses and can handle data sets having a large pool size and/or large numbers of polymorphic markers. All of the PDA functions are illustrated in the four bona fide examples. Conclusion PDA is simple to operate and does not require that users have a strong statistical background. The software is available at http://www.ibms.sinica.edu.tw/%7Ecsjfann/first%20flow/pda.htm.

  5. The Swimming Ability of Children with Asthma

    Directory of Open Access Journals (Sweden)

    Benčuriková Ľubomíra

    2017-05-01

    Full Text Available This paper reports on findings of a pilot research to determine the level of swimming ability of children with weak respiratory system aged between 10 - 11 years, who attended special classes for asthmatics. Swimming ability was assessed by 25 m free style swimming test. The results of asthmatics were compared with healthy peers (Benčuriková 2006; Kováčová 2010; Labudová 2011. The results confirmed that the level of swimming capability of asthmatic children, despite their handicap, is significantly higher than their healthy peers.

  6. Tethered swimming can be used to evaluate force contribution for short-distance swimming performance.

    Science.gov (United States)

    Morouço, Pedro G; Marinho, Daniel A; Keskinen, Kari L; Badillo, Juan J; Marques, Mário C

    2014-11-01

    The purpose of this study was two-fold: (a) to compare stroke and the physiological responses between maximal tethered and free front crawl swimming and (b) to evaluate the contribution of force exertion for swimming performance over short distances. A total of 34 male swimmers, representing various levels of competitive performance, participated in this study. Each participant was tested in both a 30-second maximal tethered swimming test and a 50-m free swimming test. The tethered force parameters, the swimming speed, stroke (stroke rate [SR]), and the physiological responses (increase in blood lactate concentration [ΔBLa], heart rate, and rate of perceived exertion) were recorded and calculated. The results showed no differences in stroke and the physiological responses between tethered and free swimming, with a high level of agreement for the SR and ΔBLa. A strong correlation was obtained between the maximum impulse of force per stroke and the speed (r = 0.91; p swimming performance. The relationship between the swimming speed and maximum force tended to be nonlinear, whereas linear relationships were observed with the maximum impulse. This study demonstrates that tethered swimming does not significantly alter stroke and the physiological responses compared with free swimming, and that the maximum impulse per stroke should be used to evaluate the balance between force and the ability to effectively apply force during sprint swimming. Consequently, coaches can rely on tethered forces to identify strength deficits and improve swimming performance over short distances.

  7. 75 FR 65261 - Virginia Graeme Baker Pool and Spa Safety Act; Public Accommodation

    Science.gov (United States)

    2010-10-22

    ... spa'' in relevant part as a ``swimming pool or spa that is open exclusively to patrons of a hotel or... proposed interpretive rule would interpret ``public accommodations facility'' to mean: ``An inn, hotel... accommodations facility'' as ``an inn, hotel, motel, or other place of lodging, including, but not limited to...

  8. What’s In the Pool? (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2013-05-30

    As summer approaches, more and more people will head to the pool, but dangers lurk in the form of waterborne diseases. In this podcast, Michele Hlavsa discusses ways to avoid waterborne diseases while swimming.  Created: 5/30/2013 by MMWR.   Date Released: 5/30/2013.

  9. Use of employments on swimming in pulling in and restoration microcycles in the training process of the highly skilled sportsmen of the highly skilled heavy weight sambo wrestlers

    Directory of Open Access Journals (Sweden)

    I.P. Zakorko

    2013-02-01

    Full Text Available Expedience of the use of the sporting and health swimming is grounded in precontest preparation of the highly skilled sportsmen unarmed self-defence. 10 sportsmen took part in research (weight over 90 kg. Offered to recommendation on the use of swimming in renewal of sportsmen after the competition and trainings loadings. On employments, swimming was utillized a method crawl on a breast and by a method breast-stroke. Length of path of pool is 25 meters. The level of influence of trainings is set on swimming of different orientation on the general consisting of the sportsman unarmed self-defence of context of preparation and renewal during the specialized competition activity. It is recommended in training on swimming to utillize overcoming at full pelt of cutting-off 250 meters in the mode to 5 minutes (time of competition fight is in the fight of sambo-5 of minutes.

  10. Vitamin D Pooling Project

    Science.gov (United States)

    The Vitamin D Pooling Project of Rarer Cancers brought together investigators from 10 cohorts to conduct a large prospective epidemiologic study of the association between vitamin D status and seven rarer cancers.

  11. Knee pain in competitive swimming.

    Science.gov (United States)

    Rodeo, S A

    1999-04-01

    The high volume of training in competitive swimming results in cumulative overload injuries. Knee pain ranks second to shoulder pain as a common complaint in competitive swimmers. Most knee pain occurs on the medial side of the knee and, most commonly, in breaststroke swimmers; however, knee pain may accompany all strokes. This article reviews the incidence of knee pain, the biomechanic and anatomic factors predisposing to injury, specific injury patterns, injury diagnosis, and the treatment and prevention of injury to the knee in swimmers.

  12. Mechanical power, thrust power and propelling efficiency: relationships with elite sprint swimming performance.

    Science.gov (United States)

    Gatta, Giorgio; Cortesi, Matteo; Swaine, Ian; Zamparo, Paola

    2018-03-01

    The purpose of this study was to explore the relationships between mechanical power, thrust power, propelling efficiency and sprint performance in elite swimmers. Mechanical power was measured in 12 elite sprint male swimmers: (1) in the laboratory, by using a whole-body swimming ergometer (W' TOT ) and (2) in the pool, by measuring full tethered swimming force (F T ) and maximal swimming velocity (V max ): W' T  = F T  · V max . Propelling efficiency (η P ) was estimated based on the "paddle wheel model" at V max . V max was 2.17 ± 0.06 m · s -1 , η P was 0.39 ± 0.02, W' T was 374 ± 62 W and W' TOT was 941 ± 92 W. V max was better related to W' T (useful power output: R = 0.943, P swimming performance. The ratio W' T /W' TOT (0.40 ± 0.04) represents the fraction of total mechanical power that can be utilised in water (e.g., η P ) and was indeed the same as that estimated based on the "paddle wheel model"; this supports the use of this model to estimate η P in swimming.

  13. Surface Disinfections: Present and Future

    Directory of Open Access Journals (Sweden)

    Matteo Saccucci

    2018-01-01

    Full Text Available The propagation of antibiotic resistance increases the chances of major infections for patients during hospitalization and the spread of health related diseases. Therefore finding new and effective solutions to prevent the proliferation of pathogenic microorganisms is critical, in order to protect hospital environment, such as the surfaces of biomedical devices. Modern nanotechnology has proven to be an effective countermeasure to tackle the threat of infections. On this note, recent scientific breakthroughs have demonstrated that antimicrobial nanomaterials are effective in preventing pathogens from developing resistance. Despite the ability to destroy a great deal of bacteria and control the outbreak of infections, nanomaterials present many other advantages. Moreover, it is unlikely for nanomaterials to develop resistance due to their multiple and simultaneous bactericidal mechanisms. In recent years, science has explored more complex antimicrobial coatings and nanomaterials based on graphene have shown great potential in antibacterial treatment. The purpose of this article is to deepen the discussion on the threat of infections related to surface disinfection and to assess the state of the art and potential solutions, with specific focus on disinfection procedures using nanomaterials.

  14. Halliwickov koncept učenja plavanja in ocenjevanje plavalnih veščin: The Halliwick concept of teaching of swimming and assessment of swimming skills: The Halliwick concept of teaching of swimming and assessment of swimming skills:

    OpenAIRE

    Groleger, Katja; Vidmar, Gaj; Vrečar, Irena

    2010-01-01

    The Halliwick concept of teaching of swimming is a comprehensive programme of adaptation to water, learning to breathe, moving in water and swimming, aimed mainly at persons with movement and/or learning disabilities of different age. Assessment of swimming ability is an integral part of the Halliwick concept. The system of Halliwick badges is used, which has recently been supplemented by the Swimming With Independent Measurement (SWIM). There is no data on sensitivity of the SWIM test in the...

  15. 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.

  16. Growing swimming algae for bioenergy

    Science.gov (United States)

    Croze, Ottavio

    Biofuel production from photosynthetic microalgae is not commercially viable due to high processing costs. New engineering and biological solutions are being sought to reduce these costs by increasing processing efficiency (productivity per energy input). Important physics, however, is ignored. For example, the fluid dynamics of algal suspensions in photobioreactors (ponds or tube arrays) is non-trivial, particularly if the algae swim. Cell reorientation by passive viscous and gravitational torques (gyrotaxis) or active reorientation by light (phototaxis) cause swimming algae in suspension to structure in flows, even turbulent ones. This impacts the distribution and dispersion of swimmers, with significant consequences for photobioreactor operation and design. In this talk, I will describe a theory that predicts swimmer dispersion in laminar pipe flows. I will then then present experimental tests of the theory, as well as new results on the circadian suspension dynamics of the algaChlamydomonas reinhardtii in lab-scale photobioreactors. Finally, I will briefly consider the implications of our work, and related active matter research, for improving algal bioprocessing efficiency. Winton Programme for the Physics of Sustainability.

  17. 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…

  18. Propulsive force in front crawl swimming

    NARCIS (Netherlands)

    Berger, M.A.M.; de Groot, G.; Hollander, A.P.

    1999-01-01

    To evaluate the propulsive forces in front crawl arm swimming, derived from a three-dimensional kinematic analysis, these values were compared with mean drag forces. The propulsive forces during front crawl swimming using the arms only were calculated using three-dimensional kinematic analysis

  19. 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

  20. 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

  1. 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.

  2. Energetics of swimming of schooling fish

    DEFF Research Database (Denmark)

    Steffensen, John Fleng

    2012-01-01

    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...... schools. Oxygen consumption of swimming fish increases exponentially or as a power function with respect to swimming speed, and hence the decrease in oxygen saturation through the school is related to the swimming speed of the school. A model describing the oxygen saturation in a fish school from front...

  3. In-depth disinfection of acrylic resins.

    Science.gov (United States)

    Chau, V B; Saunders, T R; Pimsler, M; Elfring, D R

    1995-09-01

    This study demonstrated that bacteria penetrate three kinds of dental acrylic resin after a short time period. Samples of acrylic resin were contaminated with a variety of bacteria and were then placed in three different disinfecting solutions as directed by the manufacturers. After the specific dilution and immersion time, cultures were made from the resin samples. The only effective disinfectant was a 0.525% solution of sodium hypochlorite at a 10-minute immersion. It disinfected not only the surfaces but also the bacteria that penetrated the surfaces to a depth of 3 mm.

  4. Pool water cleaning facility

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Kazuhiro; Kinoshita, Shoichiro [Hitachi Ltd., Tokyo (Japan); Asano, Takashi

    1998-05-29

    Only one system comprising a suppression poor water cleaning system (SPCU) and a filtration desalting tower (F/D) is connected for a plurality of nuclear power plants. Pipelines/valves for connecting the one system of the SPCU pump, the F/D and the plurality of nuclear power plants are disposed, and the system is used in common with the plurality of nuclear power plants. Pipelines/valves for connecting a pipeline for passing SP water to the commonly used SPCU pump and a skimmer surge tank are disposed, and fuel pool water is cooled and cleaned by the commonly used SPCU pump and the commonly used F/D. The number of SPCU pumps and the F/D facilities can be reduced, and a fuel pool water cooling operation mode and a fuel pool water cleaning operation mode which were conducted by an FPC pump so far are conducted by the SPCU pump. (N.H.)

  5. 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.

  6. Disinfection of denture base acrylic resin.

    Science.gov (United States)

    Lin, J J; Cameron, S M; Runyan, D A; Craft, D W

    1999-02-01

    During repair or adjustments of acrylic resin removable complete and partial dentures, particles of the acrylic resin from the interior of the prosthesis may expose dental personnel to microbial health hazards if the prosthesis has not been thoroughly disinfected. This study investigates the efficacy of a commercially prepared microbial disinfectant (Alcide) on the external and internal surfaces of acrylic resins. Four groups of acrylic resin were incubated in an experimental model to simulate the oral environment over time. Specimens were treated in 2 groups, disinfected and not disinfected, and then further grouped by breaking and not breaking. Analysis was performed with microbial colony counts, SEM, and statistical analyses. Viable microorganisms still remain on the internal and external surfaces of treated resins. Chlorine dioxide reduces, but does not eliminate, viable microorganisms on these dental prostheses.

  7. The critical velocity in swimming.

    Science.gov (United States)

    di Prampero, Pietro E; Dekerle, Jeanne; Capelli, Carlo; Zamparo, Paola

    2008-01-01

    In supra-maximal exercise to exhaustion, the critical velocity (cv) is conventionally calculated from the slope of the distance (d) versus time (t) relationship: d = I + St. I is assumed to be the distance covered at the expense of the anaerobic capacity, S the speed maintained on the basis of the subject's maximal O(2) uptake (VO2max) This approach is based on two assumptions: (1) the energy cost of locomotion per unit distance (C) is constant and (2) VO2max is attained at the onset of exercise. Here we show that cv and the anaerobic distance (d (anaer)) can be calculated also in swimming, where C increases with the velocity, provided that VO2max its on-response, and the C versus v relationship are known. d (anaer) and cv were calculated from published data on maximal swims for the four strokes over 45.7, 91.4 and 182.9 m, on 20 elite male swimmers (18.9 +/- 0.9 years, 75.9 +/- 6.4 kg), whose VO2max and C versus speed relationship were determined, and compared to I and S obtained from the conventional approach. cv was lower than S (4, 16, 7 and 11% in butterfly, backstroke, breaststroke and front crawl) and I (=11.6 m on average in the four strokes) was lower than d (anaer). The latter increased with the distance: average, for all strokes: 38.1, 60.6 and 81.3 m over 45.7, 91.4 and 182.9 m. It is concluded that the d versus t relationship should be utilised with some caution when evaluating performance in swimmers.

  8. Body roll in swimming: a review.

    Science.gov (United States)

    Psycharakis, Stelios G; Sanders, Ross H

    2010-02-01

    In this article, we present a critical review of the swimming literature on body roll, for the purposes of summarizing and highlighting existing knowledge, identifying the gaps and limitations, and stimulating further research. The main research findings can be summarized as follows: swimmers roll their shoulders significantly more than their hips; swimmers increase hip roll but maintain shoulder roll when fatigued; faster swimmers roll their shoulders less than slower swimmers during a 200-m swim; roll asymmetries, temporal differences in shoulder roll and hip roll, and shoulder roll side dominance exist in front crawl swimming, but there is no evidence to suggest that they affect swimming performance; and buoyancy contributes strongly to generating body roll in front crawl swimming. Based on and stimulated by current knowledge, future research should focus on the following areas: calculation of body roll for female swimmers and for backstroke swimming; differences in body roll between breathing and non-breathing cycles; causes of body roll asymmetries and their relation to motor laterality; body roll analysis across a wide range of velocities and swimming distances; exploration of the association between body roll and the magnitude and direction of propulsive/resistive forces developed during the stroke cycle; and the influence of kicking actions on the generation of body roll.

  9. 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.

  10. PROBIOTIC CLEANING PREPARATIONS VERSUS CHEMICAL DISINFECTANTS

    Directory of Open Access Journals (Sweden)

    W. Luepcke

    2017-12-01

    Full Text Available Probiotic detergents are increasingly used and are a real alternative for limiting the use of chemical cleaners, chemical disinfectants and antibiotics. They therefore have a great future because they contribute to animal health, to the hygienic production of food products of animal origin and to their harmlessness and to consumer health and environmental protection where they even have a beneficial effect on the microflora apart from chemical disinfectants that have a negative impact and destroy the beneficial microflora.

  11. The Effects of Leg Kick on Swimming Speed and Arm-Stroke Efficiency in the Front Crawl.

    Science.gov (United States)

    Silveira, Ricardo Peterson; de Souza Castro, Flávio Antônio; Figueiredo, Pedro; Vilas-Boas, João Paulo; Zamparo, Paola

    2017-07-01

    To analyze the effects of swimming pace on the relative contribution of leg kick to swimming speed and to compare arm-stroke efficiency (ηF) assessed when swimming with the arms only (SAO) and while swimming front crawl (FCS) using individual and fixed adjustments to arm-stroke and leg-kick contribution to forward speed. Twenty-nine master swimmers (21 men, 8 women) performed SAO and FCS at 6 self-selected speeds from very slow to maximal. The average swimming speed (v), stroke frequency (SF), and stroke length (SL) were assessed in the central 10 m of the swimming pool. Then, a 2nd-order polynomial regression was used to obtain values of v at paired SF. The percentage difference in v between FCS and SAO, for each paired SF, was used to calculate the relative contributions of the arm stroke (AC) and leg kick (LC) to FCS. Then ηF was calculated using the indirect "paddle-wheel" approach in 3 different ways: using general, individual, and no adjustments to AC. The LC increased with SF (and speed) from -1% ± 4% to 11% ± 1% (P arm stroke and leg kick should be individually estimated to reduce errors when calculating arm-stroke efficiency at different speeds and in different swimmers.

  12. 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.

  13. Liquid sodium pool fires

    International Nuclear Information System (INIS)

    Casselman, C.

    1979-01-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  14. 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…

  15. Swimming without a spine: Computational modeling and analysis of the swimming hydrodynamics of the Spanish Dancer.

    Science.gov (United States)

    Zhou, Zhuoyu; Mittal, Rajat

    2017-10-16

    Incompressible flow simulations are used to study the swimming of a Spanish Dancer (Hexabranchus sanguineus), a soft-bodied invertebrate marine gastropod that swims by combining body pitching with undulations of its large mantle. A simple model based on a field video is employed as the basis for the model and coupling of the flow with the body acceleration enables us to examine the free swimming of this animal. Simulations indicate propulsive efficiencies of up to about 57% and terminal swimming speeds of 1.33 body lengths per cycle. Examination of the effect of body planform on the swimming hydrodynamics suggests that the planform of this animal is likely adapted to enhance its swimming performance. © 2017 IOP Publishing Ltd.

  16. THE EFFECTS OF CREATINE LONG-TERM SUPPLEMENTATION ON MUSCLE MORPHOLOGY AND SWIMMING PERFORMANCE IN RATS

    Directory of Open Access Journals (Sweden)

    Sena Erdal

    2009-12-01

    Full Text Available Creatine (Cr has been shown to increase the total muscle mass. The purpose of this study was to investigate the effect of Cr supplementation on muscle morphology and swimming performance, using an animal model. Each rat was subjected to exercise 15-minute period daily for the 12 weeks. The rats were randomly divided into four groups: no Cr supplementation (CON, no Cr supplementation and incomplete food intake (lacking lysine and methionine in diet for rats (INCO, Cr supplementation 1 g·kg-1·day-1 (CREAT-I and Cr supplementation 2 g·kg-1·day-1 (CREAT-II. Three months later, all groups adult rats exercised in swimming pool chambers. Swimming time was recorded as minute for each rat. Following swimming performance period, the animals were killed by cervical dislocation and the gastrocnemius and diaphragm muscles were dissected. Serial slices of 5-7 μm were allocated paraffin wax and histochemical staining procedure of cross-sections was carried out with heamatoxylin-eosin technics. All groups gained body weight at the end of 12 weeks but there was no statistical difference among them. Swimming time values were statistical difference between CREAT-II and CON group as well as between CREAT-I and CON group (p < 0.05. In the INCO group was determined increased connective tissue cell of the muscle sample. In contrast, in the CREAT-I and CREAT-II group, the basic histological changes were large-scale muscle fibers and hypertrophic muscle cells. These results suggest that long-term creatine supplementation increased the number of muscle fibers and enhanced endurance swimming performance in rats

  17. Swimming championship finalist positions on success in international swimming competitions.

    Science.gov (United States)

    Yustres, I; Martín, R; Fernández, L; González-Ravé, J M

    2017-01-01

    The primary goal was to determine whether the achievement of finalist positions in the Junior Championship was associated with the achievement of success in the International Swimming Federation (FINA) World Championship (WC). Secondary goals included analyzing the effect of various factors (gender, age, country, etc) on swimmers' performances. Data were obtained from FINA information about the finalists from 2007 to 2015 WCs and finalists from 2006 to 2013 Junior-WCs (2400 entries). Final filtered database just included swimmers who participated in both junior and senior WCs (719 entries). A univariate general linear model (GLM) was used to examine the association between time; origin (swimmer who participated in Junior WC or not); maintenance years (number of years achieving finalist positions); country; and age, adjusting for year of competition. An ordinal logistic regression (OLR) model was used to identify predictors of achieving the top positions. The origin variable was not significant in either the GLM or the OLR. The only significant variables in the GLM were maintenance years (F4,706 = 7.689; p getting better positions as you get more WCs (odds = 1.85). In conclusion, no evidence was obtained to conclude finalist position in Junior WC have influence in achieve success in FINA WC. Maintenance years in WCs have a positive impact to achieve better positions.

  18. Swimming championship finalist positions on success in international swimming competitions.

    Directory of Open Access Journals (Sweden)

    I Yustres

    Full Text Available The primary goal was to determine whether the achievement of finalist positions in the Junior Championship was associated with the achievement of success in the International Swimming Federation (FINA World Championship (WC. Secondary goals included analyzing the effect of various factors (gender, age, country, etc on swimmers' performances. Data were obtained from FINA information about the finalists from 2007 to 2015 WCs and finalists from 2006 to 2013 Junior-WCs (2400 entries. Final filtered database just included swimmers who participated in both junior and senior WCs (719 entries. A univariate general linear model (GLM was used to examine the association between time; origin (swimmer who participated in Junior WC or not; maintenance years (number of years achieving finalist positions; country; and age, adjusting for year of competition. An ordinal logistic regression (OLR model was used to identify predictors of achieving the top positions. The origin variable was not significant in either the GLM or the OLR. The only significant variables in the GLM were maintenance years (F4,706 = 7.689; p < .05 and year of competition (F4,706 = 23.239; p < .05. The OLR revealed a strong association (p < .001 between the position variable and maintenance years, getting better positions as you get more WCs (odds = 1.85. In conclusion, no evidence was obtained to conclude finalist position in Junior WC have influence in achieve success in FINA WC. Maintenance years in WCs have a positive impact to achieve better positions.

  19. 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.

  20. 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....

  1. Pool gateway seal

    International Nuclear Information System (INIS)

    Starr, J.A.; Steinert, L.A.

    1983-01-01

    A device for sealing a gateway between interconnectable pools in a nuclear facility comprising a frame supporting a liquid impermeable sheet positioned in a u-shaped gateway between the pools. An inflatable tube carried in a channel in the periphery of the frame and adjoining the gateway provides a seal therebetween when inflated. A restraining arrangement on the bottom edge of the frame is releasably engagable with an adjacent portion of the gateway to restrict the movement of the frame in the u-shaped gateway upon inflation of the tube, thereby enhancing the seal. The impermeable sheet is formed of an elastomer and thus is conformable to a liquid permeable supportive wall upon application of liquid pressure to the side of the sheet opposite the wall

  2. Fuel assembly storage pool

    International Nuclear Information System (INIS)

    Hiranuma, Hiroshi.

    1976-01-01

    Object: To remove limitation of the number of storage of fuel assemblies to increase the number of storage thereof so as to relatively reduce the water depth required for shielding radioactive rays. Structure: Fuel assembly storage rack containers for receiving a plurality of spent fuel assembly racks are stacked in multi-layer fashion within a storage pool filled with water for shielding radioactive rays and removing heat. (Furukawa, Y.)

  3. CERN Electronics Pool presentations

    CERN Multimedia

    2011-01-01

    The CERN Electronics Pool has organised a series of presentations in collaboration with oscilloscope manufacturers. The last one will take place according to the schedule below.   Time will be available at the end of the presentation to discuss your personal needs. The Agilent presentation had to be postponed and will be organised later. -     Lecroy: Thursday, 24 November 2011, in 530-R-030, 14:00 to 16:30.

  4. A Single-Unit Design Structure and Gender Differences in the Swimming World Championships

    Directory of Open Access Journals (Sweden)

    Pushkar Svetlana

    2014-10-01

    Full Text Available Four 50 meter male/female finals - the freestyle, butterfly, breaststroke, and backstroke - swum during individual events at the Swimming World Championships (SWCs can be defined in four clusters. The aim of the present study was to use a single-unit design structure, in which the swimmer was defined at only one scale, to evaluate gender differences in start reaction times among elite swimmers in 50 m events. The top six male and female swimmers in the finals of four swimming stroke final events in six SWCs were analyzed. An unpaired t-test was used. The p-values were evaluated using Neo-Fisherian significance assessments (Hurlbert and Lombardi, 2012. For the freestyle, gender differences in the start reaction times were positively identified for five of the six SWCs. For the backstroke, gender differences in the start reaction times could be dismissed for five of the six SWCs. For both the butterfly and breaststroke, gender differences in the start reaction times yielded inconsistent statistical differences. Pooling all swimmers together (df = 286 showed that an overall gender difference in the start reaction times could be positively identified: p = 0.00004. The contrast between the gender differences in start reaction times between the freestyle and backstroke may be associated with different types of gender adaptations to swimming performances. When the natural groupings of swimming stroke final events were ignored, sacrificial pseudoreplication occurred, which may lead to erroneous statistical differences

  5. A single-unit design structure and gender differences in the swimming world championships.

    Science.gov (United States)

    Pushkar, Svetlana; Issurin, Vladimir B; Verbitsky, Oleg

    2014-09-29

    Four 50 meter male/female finals - the freestyle, butterfly, breaststroke, and backstroke - swum during individual events at the Swimming World Championships (SWCs) can be defined in four clusters. The aim of the present study was to use a single-unit design structure, in which the swimmer was defined at only one scale, to evaluate gender differences in start reaction times among elite swimmers in 50 m events. The top six male and female swimmers in the finals of four swimming stroke final events in six SWCs were analyzed. An unpaired t-test was used. The p-values were evaluated using Neo-Fisherian significance assessments (Hurlbert and Lombardi, 2012). For the freestyle, gender differences in the start reaction times were positively identified for five of the six SWCs. For the backstroke, gender differences in the start reaction times could be dismissed for five of the six SWCs. For both the butterfly and breaststroke, gender differences in the start reaction times yielded inconsistent statistical differences. Pooling all swimmers together (df = 286) showed that an overall gender difference in the start reaction times could be positively identified: p = 0.00004. The contrast between the gender differences in start reaction times between the freestyle and backstroke may be associated with different types of gender adaptations to swimming performances. When the natural groupings of swimming stroke final events were ignored, sacrificial pseudoreplication occurred, which may lead to erroneous statistical differences.

  6. Measurement of hydrodynamic force generation by swimming dolphins using bubble DPIV.

    Science.gov (United States)

    Fish, Frank E; Legac, Paul; Williams, Terrie M; Wei, Timothy

    2014-01-15

    Attempts to measure the propulsive forces produced by swimming dolphins have been limited. Previous uses of computational hydrodynamic models and gliding experiments have provided estimates of thrust production by dolphins, but these were indirect tests that relied on various assumptions. The thrust produced by two actively swimming bottlenose dolphins (Tursiops truncatus) was directly measured using digital particle image velocimetry (DPIV). For dolphins swimming in a large outdoor pool, the DPIV method used illuminated microbubbles that were generated in a narrow sheet from a finely porous hose and a compressed air source. The movement of the bubbles was tracked with a high-speed video camera. Dolphins swam at speeds of 0.7 to 3.4 m s(-1) within the bubble sheet oriented along the midsagittal plane of the animal. The wake of the dolphin was visualized as the microbubbles were displaced because of the action of the propulsive flukes and jet flow. The oscillations of the dolphin flukes were shown to generate strong vortices in the wake. Thrust production was measured from the vortex strength through the Kutta-Joukowski theorem of aerodynamics. The dolphins generated up to 700 N during small amplitude swimming and up to 1468 N during large amplitude starts. The results of this study demonstrated that bubble DPIV can be used effectively to measure the thrust produced by large-bodied dolphins.

  7. Front Crawl Swimming Performance and Bi-Lateral Force Asymmetry during Land-Based and Tethered Swimming Tests

    OpenAIRE

    dos Santos, Karini B.; Bento, Paulo C. Barauce; Pereira, Gleber; Payton, Carl; Rodacki, André L.F.

    2017-01-01

    The aims of this study were to investigate whether land-based and tethered swimming strength tests can explain swimming performance in 200-meter front crawl and, whether these tests were able to identify bilateral symmetry in force production. In the first session, eighteen swimmers completed a maximum effort 200 m front crawl swim (swimming performance) and 15 seconds maximal effort tethered front crawl swim. In the second session, participants performed the upper extremity isometric strengt...

  8. Disinfection of laryngoscopes: A survey of practice

    Directory of Open Access Journals (Sweden)

    Vaishali Prabhakar Chaskar

    2017-01-01

    Full Text Available Background and Aims: The laryngoscope is a common piece of equipment used by anaesthesiologists. It has been identified as a potential source of cross infection. Although guidelines exist regarding appropriate disinfection practices, recent reviews suggest ineffectiveness of current methods of disinfection and poor compliance with the established protocols. We conducted a questionnaire-based survey to study the current disinfection practices being followed by a cross section of anaesthesiologists. Methods: A simple questionnaire containing 13 questions was distributed amongst anaesthesiologists in an anaesthesia conference. Data were analysed with percentage analysis. Results: Out of 250 delegates who attended the conference, 150 submitted the completed questionnaires. Residents constituted 41% and 46% were consultants. Eighteen (12% used only tap water for cleaning and 132 (88% used a chemical agent after rinsing with water. Out of 132, 76 (51% used detergent/soap solution, 29 (19% would wash and then soak in disinfectant or germicidal agents (glutaraldehyde, povidone iodine and chlorhexidine and 18 (12% would wipe the blade with an alcohol swab. With respect to disinfection of laryngoscope handles, 70% respondents said they used an alcohol swab, 18% did not use any method, 9% were not aware of the method being used, while 3% did not respond. Conclusion: Our results indicate wide variation in methods of decontamination of laryngoscopes. Awareness regarding laryngoscope as a potential source of infection was high. We need to standardise and implement guidelines on a national level and make available resources which will help to improve patient safety.

  9. Disinfection for small water supplies: a technical guide

    CSIR Research Space (South Africa)

    Solsona, F

    1990-01-01

    Full Text Available This guide will present some disinfection systems, which will be useful in supporting disinfection programmes. The description of the different systems will provide a guideline for the selection of equipment base on balancing the simplicity...

  10. Determination of Force Coresponding to Maximal Lactate Steady State in Tethered Swimming.

    Science.gov (United States)

    Papoti, Marcelo; Vitório, Ricardo; Araújo, Gustavo G; DA Silva, Adelino S R; Santhiago, Vanessa; Martins, Luiz E B; Cunha, Sérgio A; Gobatto, Claudio A

    The main aim of the present investigation was to verify if the aerobic capacity (AC) measured in tethered swimming corresponds to the maximal lactate steady state (MLSS) and its correlation with 30 min and 400m free style swimming. Twenty-five swimmers were submitted to an incremental tethered swimming test (ITS) with an initial load of 20N and increments of 10N each 3min. After each stage of 3min, the athletes had 30s of interval to blood sample collections that were used to measure blood lactate concentrations ([La - ]). The AC BI was determined by the abrupt increase in [La - ] versus force (F). The points obtained between [La - ] versus force (N) were adjusted by an exponential curve model to determine AC corresponding to 3.5mmol.l -1 (AC 3.5 ) and 4.0mmol.l -1 (AC 4.0 ). After these procedures, the swimmers performed maximal efforts of 30min and 400m in free style swimming. We used the distance performed in 30min and the time performed in 400m to calculate the median velocities (i.e. V30 and V400) of these protocols. After one week, in order to measure the MLSS, nine athletes performed three 30-min tethered swimming efforts with intensities of 90, 100, and 110% of AC BI . The ANOVA one-way was used to compare the AC BI , AC 3.5 and AC 4.0 . Correlations between ACs, and between ACs and V30 and V400 (p0.91) and V400 (r>0.63). According to our results, it is possible to conclude that the AC BI corresponds to the MLSS, and both the AC - individually determined - and the AC - determined using fixed blood lactate concentrations of 3.5 and 4.0mmol.l -1 - can be used to predict the mean velocity of 30min and 400m in free style swimming. In addition to that, the tethered swimming system can be used for aerobic development in places where official sized swimming pools are not available, such as rehabilitation clinics and health clubs.

  11. Large molten pool heat transfer

    International Nuclear Information System (INIS)

    1994-01-01

    This workshop on large molten pool heat transfer is composed of 5 sessions which titles are: feasibility of in-vessel core debris cooling; experiments on molten pool heat transfer; calculational efforts on molten pool convection; heat transfer to the surrounding water, experimental techniques; future experiments and ex-vessel studies (RASPLAV, TOLBIAC, BALI, SULTAN, CORVIS, VULCANO, CORINE programs)

  12. DETECTION OF INFECTIOUS ADENOVIRUS IN TERTIARY TREATED AND UV DISINFECTED WASTEWATER DURING A UV DISINFECTION PILOT STUDY

    Science.gov (United States)

    An infectious enteric adenovirus was isolated from urban wastewater receiving tertiary treatment and ultraviolet (UV) disinfection. A pilot study was undertaken to investigate the efficacy of UV disinfection (low pressure, high intensity radiation) of total and fecal coliform bac...

  13. Intracellular mechanisms of solar water disinfection

    Science.gov (United States)

    Castro-Alférez, María; Polo-López, María Inmaculada; Fernández-Ibáñez, Pilar

    2016-12-01

    Solar water disinfection (SODIS) is a zero-cost intervention measure to disinfect drinking water in areas of poor access to improved water sources, used by more than 6 million people in the world. The bactericidal action of solar radiation in water has been widely proven, nevertheless the causes for this remain still unclear. Scientific literature points out that generation of reactive oxygen species (ROS) inside microorganisms promoted by solar light absorption is the main reason. For the first time, this work reports on the experimental measurement of accumulated intracellular ROS in E. coli during solar irradiation. For this experimental achievement, a modified protocol based on the fluorescent probe dichlorodihydrofluorescein diacetate (DCFH-DA), widely used for oxidative stress in eukaryotic cells, has been tested and validated for E. coli. Our results demonstrate that ROS and their accumulated oxidative damages at intracellular level are key in solar water disinfection.

  14. OPTIMAL SCHEDULING OF BOOSTER DISINFECTION IN WATER DISTRIBUTION SYSTEMS

    Science.gov (United States)

    Booster disinfection is the addition of disinfectant at locations distributed throughout a water distribution system. Such a strategy can reduce the mass of disinfectant required to maintain a detectable residual at points of consumption in the distribution system, which may lea...

  15. Chemical aspects of peracetic acid based wastewater disinfection ...

    African Journals Online (AJOL)

    Peracetic acid (PAA) has been studied for wastewater disinfection applications for some 30 years and has been shown to be an effective disinfectant against many indicator microbes, including bacteria, viruses, and protozoa. One of the key advantages compared to, e.g., chlorine is the lack of harmful disinfection ...

  16. 178 efficacy of three disinfectant formulations against multidrug ...

    African Journals Online (AJOL)

    boaz

    Intended application either for antiseptic or disinfection. -. Environmental factors such as presence of organic matter or specificity of microorganism to a particular environment. -. Toxicity of the agent i.e disinfectant toxicity effect. In the hospitals, disinfectants have been found to play an important role in the prevention and ...

  17. Effects of some antiseptics and disinfectants on Staphylococcus ...

    African Journals Online (AJOL)

    A total of 6 antiseptics and disinfectants at varying concentrations (20% - 100%) and contact time (10-60 minutes) were tested for the efficacy in the reduction of Staphylococcus aureus isolated from the hands of volunteers. Disinfectant 1 was the most effective disinfectant being bactericidal to S. aureus at 100% ...

  18. THE TOXICOLOGY OF COMPLEX MIXTURES OF DISINFECTION BY-PRODUCTS

    Science.gov (United States)

    Chemical disinfection of water is a major public health advance that has decreased dramatically water-borne disease. Chemical disinfectants react with naturally occurring organic and inorganic matter in water to produce a wide variety of disinfection byproducts (DBPs). DBP num...

  19. Disinfection studies of Nahar ( Mesua ferrea ) seed kernel oil using ...

    African Journals Online (AJOL)

    As a result of disinfection byproducts (DBP) concerns from chlorine, Environmental Protection Agency (EPA) as well as the water treatment industry, place more emphasis on the use of disinfectants other than chlorine. Disinfection also plays a key role in the reclamation and reuse of wastewater for eliminating infectious ...

  20. Disinfection of sewage sludge with gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Melmed, L.N.; Comninos, D.K.

    1979-10-01

    Disinfection of sewage sludge by ionizing radiation, thermoradiation, and radiation combined with oxygenation was investigated in experimentation in Johannesburg, South Africa. Inactivation of Ascaris lumbricoides ova was used as the criterion of disinfection. Experimentation and methodology are explained. Complete inactivation could be obtained when 0.5 kGy radiation was applied at 50..cap alpha..C to a sludge containing 3% solids and when 0.4 kGy radiation was applied at 55..cap alpha..C to a sludge with 20% solids. (1 drawing, 5 graphs, 4 photos, 4 tables)

  1. Ultraviolet air disinfection for protection against influenza

    International Nuclear Information System (INIS)

    Riley, R.L.

    1977-01-01

    Three converging lines of evidence support the belief that it may be possible, under appropriate circumstances, to interrupt the airborne transmission of influenza by ultraviolet (UV) air disinfection. These lines of evidence are: (a) that influenza is airborne; (b) that UV irradiation of the upper air of a room can provide safe and effective disinfection of air in the lower part of the room; and (c) that epidemic spread of airborne viral infections in humans can be prevented if the population under consideration remains in the UV-protected environment

  2. COLPEX - Cold Pool Experiment

    Science.gov (United States)

    Wells, H.; Price, J.; Horlacher, V.; Sheridan, P. F.; Vosper, S. B.; Brown, A. R.; Mobbs, S. D.; Ross, A. N.

    2009-04-01

    Planning has started towards designing a new field campaign aimed at studying the behaviour of the boundary layer over complex terrain. Of specific interest is the formation of cold-pools in valleys during stable night-time conditions. The field campaign will run continuously until the end of the winter in 2009/10. The experiment will make use of a wide variety of ground-based sensors including turbulence towers, automatic weather stations, Doppler lidar, radiation sensors and soil temperature probes. We also hope to deploy an instrumented car and a tethered balloon facility for limited periods. Data from the field campaign will be used for a number of purposes. Firstly, to increase our understanding of how the valley cold pools form and why, for instance, some valleys offer a more favourable environment for their formation than others. Secondly, to investigate the formation and dissipation of fog in complex terrain. Thirdly, the data set will also be used to help validate and develop the Met Office Unified Model at high resolution. An area for the experiment has been identified in the Shropshire/Powis area of the UK where a network of valleys and low hills exist with a typical valley width of ~1.5km and hill top to valley floor heights of 75-200m. 0m.

  3. Intermittent Swimming with a Flexible Propulsor

    Science.gov (United States)

    Akoz, Emre; Moored, Keith

    2017-11-01

    Aquatic animals use a variety of swimming gaits to propel themselves efficiently through the oceans. One type of gait known as intermittent or burst-and-coast swimming is used by species such as saithe, cod and trout. Recent studies have shown that this gait can save up to 60% of a swimmer's energy by exploiting an inviscid Garrick mechanism. These detailed studies have examined the effects of an intermittent swimming gait on rigid propulsors, yet the caudal fins of intermittent swimmers are in fact highly flexible propulsors. In this respect, to gain a comprehensive understanding of intermittent swimming, the effect of elasticity on the swimming performance and wake flow of an intermittent swimmer is investigated. To accomplish this a torsional spring structural model is strongly coupled to a fast boundary element method solver that captures the fluid-structure interaction of a two-dimensional self-propelled intermittently pitching hydrofoil. It is shown that flexibility introduces extra vortices to the coasting phase of motion that can either promote or diminish thrust production depending upon the hydrofoil parameters. An optimal intermittent flexible swimmer is shown to increase its efficiency by as much as 28% when compared to an optimal continuous flexible swimmer. Supported by the Office of Naval Research under Program Director Dr. Bob Brizzolara, MURI Grant Number N00014-14-1-0533.

  4. Propulsive force asymmetry during tethered-swimming.

    Science.gov (United States)

    dos Santos, K B; Pereira, G; Papoti, M; Bento, P C B; Rodacki, A

    2013-07-01

    This study aimed to determine whether: i) tethe-red-swimming can be used to identify the asymmetry during front crawl swimming style; ii) swimmers that perform unilateral breathing present greater asymmetry in comparison to others that use bilateral breathing; iii) swimmers of best performance present smaller asymmetry than their counterparts; iv) repeated front crawl swimming movements influence body asymmetry. 18 swimmers were assessed for propulsive force parameters (peak force, mean force, impulse and rate of force development) during a maximal front crawl tethered-swimming test lasting 2 min. A factorial analysis showed that propulsive forces decreased at the beginning, intermediate and end of the test (pforce parameters (p>0.05). When performance was considered (below or above mean group time), a larger asymmetry was found in the sub-group of lower performance in comparison to those of best performance (pforces can be detected using tethered-swimming. The propulsive forces decreased during the test but asymmetries did not change under testing conditions. Although breathing preference did not influence asymmetry, swimmers with best performance were less asymmetric than their counterparts. © Georg Thieme Verlag KG Stuttgart · New York.

  5. PHYSIOLOGICAL, BIOMECHANICAL AND ANTHROPOMETRICAL PREDICTORS OF SPRINT SWIMMING PERFORMANCE IN ADOLESCENT SWIMMERS

    Directory of Open Access Journals (Sweden)

    Evelin Lätt

    2010-09-01

    Full Text Available The purpose of this study was to analyze the relationships between 100-m front crawl swimming performance and relevant biomechanical, anthropometrical and physiological parameters in male adolescent swimmers. Twenty five male swimmers (mean ± SD: age 15. 2 ± 1.9 years; height 1.76 ± 0.09 m; body mass 63.3 ± 10.9 kg performed an all-out 100-m front crawl swimming test in a 25-m pool. A respiratory snorkel and valve system with low hydrodynamic resistance was used to collect expired air. Oxygen uptake was measured breath-by-breath by a portable metabolic cart. Swimming velocity, stroke rate (SR, stroke length and stroke index (SI were assessed during the test by time video analysis. Blood samples for lactate measurement were taken from the fingertip pre exercise and at the third and fifth minute of recovery to estimate net blood lactate accumulation (?La. The energy cost of swimming was estimated from oxygen uptake and blood lactate energy equivalent values. Basic anthropometry included body height, body mass and arm span. Body composition parameters were measured using dual-energy X-ray absorptiometry (DXA. Results indicate that biomechanical factors (90.3% explained most of 100-m front crawl swimming performance variability in these adolescent male swimmers, followed by anthropometrical (45.8% and physiological (45.2% parameters. SI was the best single predictor of performance, while arm span and ∆La were the best anthropometrical and physiological indicators, respectively. SI and SR alone explained 92.6% of the variance in competitive performance. These results confirm the importance of considering specific stroke technical parameters when predicting success in young swimmers.

  6. 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

  7. Swimming type inspection device and system thereof

    International Nuclear Information System (INIS)

    Ito, Arata; Kimura, Motohiko; Ito, Tomoyuki

    1998-01-01

    The present invention provides a swimming type inspection device which can be reduced in the size, easily accessible to each portion of a reactor, and increase the degree of freedom of swimming and visual range, and facilitate visual inspection. The swimming type inspection device comprises two photographing devices, a device which can obtain propelling force by rotation of impellers, two second propelling devices having impellers disposed in perpendicular to the rotating axis of the impellers of the first propelling device, a control device for controlling control signals of first and second propelling devices and driving devices therefor and control image signals of the photographing devices, and transmission section for wireless transmitting of the control signals and the image signals. (N.H.)

  8. Swimming and feeding of mixotrophic biflagellates

    DEFF Research Database (Denmark)

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

    2017-01-01

    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......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......, predation risk due to flow-sensing predators, and prey capture? Here, we describe measured flows around two species of mixotrophic, biflagellated haptophytes with qualitatively different flagellar arrangements and beat patterns. We model the near cell flows using two symmetrically arranged point forces...

  9. 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 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...

  10. Swimming economy: determinant factors and assessment issues

    Directory of Open Access Journals (Sweden)

    Giovanni Novaes

    2006-09-01

    Full Text Available Swimming economy is an important parameter in the control of the training process, since it has been demonstrated that this concept is related to the swimming performance. Swimming economy is affected by physiological and biomechanical constraints, therefore being a concept that reflects the swimmers´ adaptation to the liquid environment in those two domains. A review of the literature about swimming economy is presented, focusing some of the most relevant studies that have been conducted on this issue. Other than the biomechanical and physiological constraints, the swimming economy is influenced by other factors such as: swimming velocity, technical ability, training status, gender, age and anthropometric characteristics. Therefore a multitude of aspects are pertinent in the assessment of swimming economy and in the application of this concept in the control of the swimmers’ training process. A proper assessment of the swimming economy requires the direct measurement of the oxygen uptake. The choice of the protocol to assess the swimming economy must be carefully done. Particular attention must be paid to the oxygen uptake kinetics across the different levels of exercise intensity. Therefore, both exercise intensity and duration are to be considered. The attainment of swimming velocities as close as possible to the competition velocity is also an important issue. Although few studies have measured directly the oxygen uptake of top-level performers during swimming, the literature shows that a discontinuous protocol, with increasing exercise bouts of duration between three and six minutes seem appropriate to assess the swimming economy. RESUMO Economia de nado é um parâmetro importante no controle do processo de treinamento, desde que foi demonstrado que este conceito é relacionado ao desempenho de nado. Economia de nado é afetada por aspectosfisiológicos e biomecânicos, sendo então um conceito que reflete a adaptação de nadadores ao

  11. 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.

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

    Science.gov (United States)

    Jizhuang, Fan; Wei, Zhang; Bowen, Yuan; Gangfeng, Liu

    2017-04-15

    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. © 2017. Published by The Company of Biologists Ltd.

  13. 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.

  14. Determination of a quantitative parameter to evaluate swimming technique based on the maximal tethered swimming test.

    Science.gov (United States)

    Soncin, Rafael; Mezêncio, Bruno; Ferreira, Jacielle Carolina; Rodrigues, Sara Andrade; Huebner, Rudolf; Serrão, Julio Cerca; Szmuchrowski, Leszek

    2017-06-01

    The aim of this study was to propose a new force parameter, associated with swimmers' technique and performance. Twelve swimmers performed five repetitions of 25 m sprint crawl and a tethered swimming test with maximal effort. The parameters calculated were: the mean swimming velocity for crawl sprint, the mean propulsive force of the tethered swimming test as well as an oscillation parameter calculated from force fluctuation. The oscillation parameter evaluates the force variation around the mean force during the tethered test as a measure of swimming technique. Two parameters showed significant correlations with swimming velocity: the mean force during the tethered swimming (r = 0.85) and the product of the mean force square root and the oscillation (r = 0.86). However, the intercept coefficient was significantly different from zero only for the mean force, suggesting that although the correlation coefficient of the parameters was similar, part of the mean velocity magnitude that was not associated with the mean force was associated with the product of the mean force square root and the oscillation. Thus, force fluctuation during tethered swimming can be used as a quantitative index of swimmers' technique.

  15. 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.

  16. Evaluation of the efficacy of chemical disinfectants for disinfection of heat-polymerised acrylic resin.

    Science.gov (United States)

    Orsi, Iara Augusta; Junior, Adalton Garcia; Villabona, Camilo Andrés; Fernandes, Flávio Henrique Carriço Nogueira; Ito, Isabel Yoko

    2011-12-01

    This study evaluated the efficacy of disinfectants on the internal aspect of heat-polymerised acrylic resin contaminated with microbial strains. Dentures absorb oral fluids and become contaminated by different microorganisms. Two hundred and fifty rectangular specimens were made of heat-polymerised acrylic resin, and then divided into five groups corresponding to the microbial strains (Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, S. mutans and Enterococcus faecalis). After contamination, the specimens were immersed in 1 and 2% sodium hypochlorite and 2% glutaraldehyde for periods of 5, 10 and 15 min. The specimens were placed into tubes containing different broths and incubated at 35°C and then visually analysed. Turbidity in the medium indicated microbial growth. The Fisher's exact test was used in the analysis of the results. The strain E. faecalis was the most resistant to the disinfectant solutions, and among them, glutaraldehyde was more effective than 2 and 1% hypochlorite for disinfection for 5 min; in the 10-min period there were no differences between the disinfectants. In 15 min of immersion, 1% hypochlorite and glutaraldehyde were more effective than 2% hypochlorite. Disinfection for 10 min with 1% hypochlorite and glutaraldehyde is effective in disinfecting the internal aspect of heat-polymerised acrylic resin. © 2010 The Gerodontology Society and John Wiley & Sons A/S.

  17. 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...

  18. Front Crawl Swimming Performance and Bi-Lateral Force Asymmetry during Land-Based and Tethered Swimming Tests

    Directory of Open Access Journals (Sweden)

    Karini B. dos Santos, Paulo C. Barauce Bento, Gleber Pereira, Carl Payton, André L.F. Rodacki

    2017-12-01

    Full Text Available The aims of this study were to investigate whether land-based and tethered swimming strength tests can explain swimming performance in 200-meter front crawl and, whether these tests were able to identify bilateral symmetry in force production. In the first session, eighteen swimmers completed a maximum effort 200 m front crawl swim (swimming performance and 15 seconds maximal effort tethered front crawl swim. In the second session, participants performed the upper extremity isometric strength test. Peak force production of tethered swimming and isometric strength tests were significantly correlated for the strongest and weakest sides (r = 0.58 and r = 0.63, respectively; p < 0.05, but only peak force production during tethered swimming correlated with 200 m swimming performance time (r = -0.55, p < 0.05. Bilateral asymmetries in peak force and rate of force development were similar between the tethered swimming and isometric strength tests (peak force: 13%, p = 0.24; rate of force development: 15%, p = 0.88 However, both tests detected significant difference of peak force and rate of force development between body sides. The tethered swimming test can partially explain the 200 m front crawl swimming performance. In addition, the land-based and tethered swimming tests may be used to identify bilateral asymmetry of swimming

  19. Front Crawl Swimming Performance and Bi-Lateral Force Asymmetry during Land-Based and Tethered Swimming Tests.

    Science.gov (United States)

    Dos Santos, Karini B; Bento, Paulo C Barauce; Pereira, Gleber; Payton, Carl; Rodacki, André L F

    2017-12-01

    The aims of this study were to investigate whether land-based and tethered swimming strength tests can explain swimming performance in 200-meter front crawl and, whether these tests were able to identify bilateral symmetry in force production. In the first session, eighteen swimmers completed a maximum effort 200 m front crawl swim (swimming performance) and 15 seconds maximal effort tethered front crawl swim. In the second session, participants performed the upper extremity isometric strength test. Peak force production of tethered swimming and isometric strength tests were significantly correlated for the strongest and weakest sides (r = 0.58 and r = 0.63, respectively; p force production during tethered swimming correlated with 200 m swimming performance time (r = -0.55, p force and rate of force development were similar between the tethered swimming and isometric strength tests (peak force: 13%, p = 0.24; rate of force development: 15%, p = 0.88) However, both tests detected significant difference of peak force and rate of force development between body sides. The tethered swimming test can partially explain the 200 m front crawl swimming performance. In addition, the land-based and tethered swimming tests may be used to identify bilateral asymmetry of swimming.

  20. Carbon nanoparticles for solar disinfection of water.

    Science.gov (United States)

    Maddigpu, Pratap Reddy; Sawant, Bhairavi; Wanjari, Snehal; Goel, M D; Vione, Davide; Dhodapkar, Rita S; Rayalu, S

    2018-02-05

    The present manuscript deals with the application of carbon nano particles (CNP) and chitosan (CHIT) in the form of CHIT-CNP composite for the disinfection of water. The CHIT-CNP composite was prepared by the solution casting method and characterized by TEM, XRD and elemental analysis. In the present investigation we study the disinfection efficiency towards E. coli bacteria of both CNP and CHIT-CNP, under sunlight (SODIS) in identical experimental conditions. Both CNP and CHIT-CNP enhanced disinfection as compared to SODIS alone, and comparable performance was achieved when the same dose of CNP in the two materials was applied. However, the CHIT-CNP composite is in the form of a fabric and it is easier to use and handle as compared to the CNP powder, especially in rural and resource-constrained areas. Moreover the SODIS-CHIT-CNP setup, when used in a compound parabolic collector (CPC) reactor showed high bactericidal efficiency compared to SODIS alone, which is promising for practical applications. The disinfection potential of the CNP powder was compared with that of the well-known material TiO 2 Degussa P25 (DP 25 ): DP 25 gave 6-log kill of bacteria in 180min, whereas CNP produced 6-log kill in 150min. Copyright © 2017. Published by Elsevier B.V.

  1. Effect Of Virkon Disinfectant Brand Of Potassium ...

    African Journals Online (AJOL)

    In the Nigerian market are many brands of disinfectants with varying efficacy against bacteria, fungi and viruses. Recently Virkon brand of potassium monoperoxysulphate (Antec, UK) was introduced. The Kelsey -Sykes test was carried out to determine the efficacy of Virkon against standard bacterial strains and ...

  2. Microbial contamination and disinfection methods of pacifiers.

    Science.gov (United States)

    Nelson-Filho, Paulo; Louvain, Márcia Costa; Macari, Soraia; Lucisano, Marília Pacífico; Silva, Raquel Assed Bezerra da; Queiroz, Alexandra Mussolino de; Gaton-Hernández, Patrícia; Silva, Léa Assed Bezerra da

    2015-10-01

    To evaluate the microbial contamination of pacifiers by Mutans Streptococci(MS) and the efficacy of different methods for their disinfection. Twenty-eight children were assigned to a 4-stage changeover system with a 1-week interval. In each stage, children received a new pacifier and the parents were instructed to maintain their normal habits for 1 week. After this time, the pacifiers were subjected to the following 4 disinfection methods: spraying with 0.12% chlorhexidine solution, Brushtox or sterile tap water, and immersion in boiling tap water for 15 minutes. Microbiological culture for MS and Scanning Electron Microscopy (SEM) were performed. The results were analyzed statistically by Friedman's non-parametric test (a=0.05). The 0.12% chlorhexidine spray was statistically similar to the boiling water (p>0.05) and more effective than the Brushtox spray and control (pPacifiers become contaminated by MS after their use by children and should be disinfected routinely. Spraying with a 0.12% chlorhexidine solution and immersion in boiling water promoted better disinfection of the pacifiers compared with a commercial antiseptic toothbrush cleanser (Brushtox).

  3. Antibiotic and disinfectant resistance of Salmonella serovars ...

    African Journals Online (AJOL)

    The Salmonella isolates tested displayed multiple antibiotic resistance to a number of antibiotics used to treat both humans and animals. No resistance was seen to disinfectants used at the manufacturer\\'s recommended rate of dilution. The bacteria were resistant, though, at lower dilutions, highlighting the necessity of ...

  4. STERILIZATION AND DISINFECTION IN A PRIVATE CLINIC

    African Journals Online (AJOL)

    Oral examination is done with a mirror and probe. The mirror is then washed under the tap water and disinfected in 'V3 sterilizing' fluid concentrate. The probe is placed in a tray with ... Protective glasses are worn additionally to the gloves and facemask, when cavity preparation. is being performed. The handpiece is wiped.

  5. Microbial contamination and disinfection methods of pacifiers

    Directory of Open Access Journals (Sweden)

    Paulo NELSON-FILHO

    2015-10-01

    Full Text Available Objectives To evaluate the microbial contamination of pacifiers by Mutans Streptococci(MS and the efficacy of different methods for their disinfection.Methods Twenty-eight children were assigned to a 4-stage changeover system with a 1-week interval. In each stage, children received a new pacifier and the parents were instructed to maintain their normal habits for 1 week. After this time, the pacifiers were subjected to the following 4 disinfection methods: spraying with 0.12% chlorhexidine solution, Brushtox® or sterile tap water, and immersion in boiling tap water for 15 minutes. Microbiological culture for MS and Scanning Electron Microscopy (SEM were performed. The results were analyzed statistically by Friedman’s non-parametric test (a=0.05.Results The 0.12% chlorhexidine spray was statistically similar to the boiling water (p>0.05 and more effective than the Brushtox®spray and control (p<0.05. The analysis of SEM showed the formation of a cariogenic biofilm in all groups with positive culture.Conclusions Pacifiers become contaminated by MS after their use by children and should be disinfected routinely. Spraying with a 0.12% chlorhexidine solution and immersion in boiling water promoted better disinfection of the pacifiers compared with a commercial antiseptic toothbrush cleanser (Brushtox®.

  6. Disinfection of Vegetative Cells of Bacillus anthracis

    Science.gov (United States)

    2016-03-01

    Society for Microbiology ; New Orleans, LA, 2004. American Public Health Association. Standard Methods for the Examination of Water and Wastewater...Disinfection kinetics of vegetative cells of Bacillus anthracis in water with free available chlorine ([FAC] 2 mg/L) and monochloramine ([MC] 2 mg/L) were...anthracis. Bacillus anthracis cells Drinking water Chlorine demand-free (CDF

  7. A study of some radioprotection apparatuses used in the case of pool reactors

    International Nuclear Information System (INIS)

    Robien, E. de; Choudens, H. de; Delpuech, J.

    1965-01-01

    Various problems of radioprotection concerning swimming-pool reactors in Grenoble have led us to study adequate solutions: a) The automatic verification of the staff-radioactivity when coming out of Melusine or Siloe has been realized thanks to a βγ gate which is insensitive to the ambient background in the reactor-hall; b) The automatic verification of the contamination of the shoes of the agents working in these reactors has been realized with a dedicated device; c) The necessity to measure precisely γ doses with the help of an autonomous apparatus has led to the making of a plastic-scintillator γ dosimeter; d) The obligation to forbid the opening of doors in some places where there might be a great intensity of radiation, has led us to make doors open according to the intensity of radiation inside the rooms; e) The releases of radioactive iodine have been measured with activated charcoal cartridges that surround a scintillator connected with a unique channel selector; f) Finally the control of reactor safety rod fall in case of a radioactive accident has been secured by a chain whose detector is a chamber immersed in the swimming-pool, which offers, in the particular case of the hot thickness swimming-pool reactor a double advantage: first it enables us to regulate the upper hot water layer, second to get free of transitory radiations which appear in the reactor hall as the experimental apparatuses are taken out from the core. (authors) [fr

  8. Disinfection of dental impressions - compliance to accepted standards.

    Science.gov (United States)

    Almortadi, N; Chadwick, R G

    2010-12-18

    The responsibility of ensuring impressions have been cleaned and disinfected before dispatch to the dental laboratory lies solely with the dentist. Uncertainty of impression disinfection risks both the health of the receiving dental technician and potential repeat disinfection of an already disinfected impression with detrimental consequences for its dimensions. To ascertain, from the perspectives of dentists and dental technicians, current impression decontamination and disinfection practices with, in the case of the technicians, an estimate of the relative prevalence of contaminated voids within apparently disinfected impressions. Anonymous postal questionnaire. Dentist (n = 200) and dental technician (n = 200) potential participants, selected at random from the registers held by the General Dental Council, were invited to complete an anonymous postal questionnaire that sought to establish current practices and perceived effectiveness of impression disinfection. Questionnaire return rates of 42.1% and 31.2% were recorded for dentists and dental technicians respectively. A wide range of solutions, at different dilutions of the same product, was used by the dentists to disinfect dental impressions. 37.2% rinsed the impressions with water, and 2.6% always brushed debris away, before disinfection. 24.7% of dentists did not inform the laboratory of disinfection. Irrespective of the disinfection status of the received impressions, 50% of the responding dental technicians disinfected all impressions. 95% of them had received blood-contaminated impressions. 15% had encountered blood-filled voids upon trimming back the peripheries of impressions. 64.7% were confident that the impressions received by them had been disinfected by the dentists. Compliance with good practice is less than ideal and education in impression disinfection for both dentists and dental technicians is required to address this.

  9. Use of the Term “Shock” in Swimming Pool, Hot Tubs, and Spa Products

    Science.gov (United States)

    EPA has determined that shock treatment and super-chlorination are terms usually used to describe claims to kill or control visible algae growth. Claims to kill, prevent or control algae or bacteria are pesticide claims.

  10. Fast neutron spectrum in the reflector of swimming pool reactor behind metallics slabs

    International Nuclear Information System (INIS)

    Brousse, J.C.

    1970-01-01

    The large perturbations of fast neutron spectrum were measured behind lead, aluminium and iron slabs in the Siloette reflector at the CENG. The neutron slowing down is chiefly depending of the inelastic reaction. The reaction cross section increases with energy; a spectrum softening is deduced. This is verified. We tried to determine the spectrum shape by calculation to fit the measurements. Calculations were firstly made in unidimensional geometry by the NIOBE transport equation resolution code and by the SANE Monte-Carlo code. The results does not agree with the experimental determined values. Finally a semi-empirical method for studying a tridimensional geometry was chosen. We have obtained calculation results in a perfect agreement with measurements. The method is described. (author) [fr

  11. Experimental study on the impulsive load of follow fuel assembly of swimming pool research reactor

    International Nuclear Information System (INIS)

    Sun Changlong; Bo Hanliang; Jiang Shengyao; Zhang Hongchao; Ma Cang; Wang Jinhua; Qin Benke

    2005-01-01

    Through the data of impulsive load experiment on this fuel assembly, this paper obtained how the impact force and impact acceleration changed with time and other parameters, and analyzed the causation of the different impact force and impact acceleration, further more, found the disciplinarian of impulsive load. Investigation showed: the fuel assembly of electromagnetic movable coil control rod drive mechanism is firm enough to suffer from the impulsive load, so it suits using in the reactor. (authors)

  12. Specifies of teaching swimming to children with autism spectrum disorder

    OpenAIRE

    Baštová, Miroslava

    2017-01-01

    Title: Specifics of teaching swimming to children with autism spectrum disorder. Objectives: Creation and implementation of the concept of preparatory and basic swimming lessons for children with autism spectrum disorder. Evaluation of information on continuing education and the achieved level of swimming skills and swimming locomotion observed in children with autism spectrum disorder. Presentation and qualitative assessment of the four case studies and subsequent design of guidelines for sw...

  13. Efficacy of a modified tapering protocol on swimming performance ...

    African Journals Online (AJOL)

    Performance assessment following tapering consisted of 2 swims over a distance of 200 m, with a recovery period of 5 hours between swims. After resuming normal ... Total time and split times for each length, stroke rate, distance per stroke, and stroke index in a performance swim were determined as well as heart rate (HR) ...

  14. 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 pr...

  15. Ion-swimming speed variation of Vibrio cholerae cells

    Indian Academy of Sciences (India)

    In the present work we report the variation in swimming speed of Vibrio cholerae with respect to the change in concentration of sodium ions in the medium. We have also studied the variation in swimming speed with respect to temperature. We find that the swimming speed initially shows a linear increase with the increase of ...

  16. Morphology of drying blood pools

    Science.gov (United States)

    Laan, Nick; Smith, Fiona; Nicloux, Celine; Brutin, David; D-Blood project Collaboration

    2016-11-01

    Often blood pools are found on crime scenes providing information concerning the events and sequence of events that took place on the scene. However, there is a lack of knowledge concerning the drying dynamics of blood pools. This study focuses on the drying process of blood pools to determine what relevant information can be obtained for the forensic application. We recorded the drying process of blood pools with a camera and measured the weight. We found that the drying process can be separated into five different: coagulation, gelation, rim desiccation, centre desiccation, and final desiccation. Moreover, we found that the weight of the blood pool diminishes similarly and in a reproducible way for blood pools created in various conditions. In addition, we verify that the size of the blood pools is directly related to its volume and the wettability of the surface. Our study clearly shows that blood pools dry in a reproducible fashion. This preliminary work highlights the difficult task that represents blood pool analysis in forensic investigations, and how internal and external parameters influence its dynamics. We conclude that understanding the drying process dynamics would be advancement in timeline reconstitution of events. ANR funded project: D-Blood Project.

  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. Swimming obstructed by dead-water

    NARCIS (Netherlands)

    Ganzevles, S.P.M; Nuland, F.S.W.; Maas, L.; Toussaint, H.M.

    2009-01-01

    In nautical literature, ‘dead-water’ refers to the obstructive effect encountered by ships moving in stratified water due to the ship generating waves on an interface that separates different water masses. To investigate the hypothesis that open water swimming may also be obstructed by an encounter

  19. Swimming obstructed by dead-water

    NARCIS (Netherlands)

    Ganzevles, S.P.; Nuland, F.S.; Maas, L.R.; Toussaint, H.M.

    2009-01-01

    In nautical literature, 'dead-water' refers to the obstructive effect encountered by ships moving in stratified water due to the ship generating waves on an interface that separates different water masses. To investigate the hypothesis that open water swimming may also be obstructed by an encounter

  20. 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.…

  1. 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…

  2. 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

  3. 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.

  4. What Research Tells the Coach About Swimming.

    Science.gov (United States)

    Faulkner, John A.

    This booklet is designed to make research findings about swimming available with interpretations for practical application. Chapter 1, "Physical Characteristics of Swimmers," discusses somatotyping, body composition, and growth. Chapter 2, "Physiological Characteristics of Swimmers," discusses resting rate, vital capacity, effects of water…

  5. Aerobic and anaerobic performances in tethered swimming.

    Science.gov (United States)

    Papoti, M; da Silva, A S R; Araujo, G G; Santiago, V; Martins, L E B; Cunha, S A; Gobatto, C A

    2013-08-01

    The purpose of this study was to investigate whether the critical force (CritF) and anaerobic impulse capacity (AIC) - estimated by tethered swimming - reflect the aerobic and anaerobic performance of swimmers. 12 swimmers performed incremental test in tethered swimming to determine lactate anaerobic threshold (AnTLAC), maximal oxygen uptake ( ˙VO2MAX) and force associated with the ˙VO2MAX (i ˙VO2MAX). The swimmers performed 4 exhaustive (tlim) exercise bouts (100, 110, 120 and 130% i ˙VO2MAX) to compute the CritF and AIC (F vs. 1/tlim model); a 30-s all-out tethered swimming bout to determine their anaerobic fitness (ANF); 100, 200, and 400-m time-trials to determine the swimming performance. CritF (57.09±11.77 N) did not differ from AnTLAC (53.96±11.52 N, (P>0.05) but was significantly lower than i ˙VO2MAX (71.02±8.36 N). In addition, CritF presented significant correlation with AnTLAC (r=0.76; Pswimming. © Georg Thieme Verlag KG Stuttgart · New York.

  6. How do amoebae swim and crawl?

    Directory of Open Access Journals (Sweden)

    Jonathan D Howe

    Full Text Available The surface behaviour of swimming amoebae was followed in cells bearing a cAR1-paGFP (cyclic AMP receptor fused to a photoactivatable-GFP construct. Sensitized amoebae were placed in a buoyant medium where they could swim toward a chemoattractant cAMP source. paGFP, activated at the cell's front, remained fairly stationary in the cell's frame as the cell advanced; the label was not swept rearwards. Similar experiments with chemotaxing cells attached to a substratum gave the same result. Furthermore, if the region around a lateral projection near a crawling cell's front is marked, the projection and the labelled cAR1 behave differently. The label spreads by diffusion but otherwise remains stationary in the cell's frame; the lateral projection moves rearwards on the cell (remaining stationary with respect to the substrate, so that it ends up outside the labelled region. Furthermore, as cAR1-GFP cells move, they occasionally do so in a remarkably straight line; this suggests they do not need to snake to move on a substratum. Previously, we suggested that the surface membrane of a moving amoeba flows from front to rear as part of a polarised membrane trafficking cycle. This could explain how swimming amoebae are able to exert a force against the medium. Our present results indicate that, in amoebae, the suggested surface flow does not exist: this implies that they swim by shape changes.

  7. Swimming of the pea crab (Pinnotheres pisum)

    NARCIS (Netherlands)

    Versteegh, C.P.C.; Muller, M.

    2014-01-01

    Aquatic organisms have to deal with different hydrodynamic regimes, depending on their size and speed during locomotion. The pea crab swims by beating the third and fourth pereiopod on opposite sides as pairs. Using particle tracking velocimetry and high-speed video recording, we quantify the

  8. [Lumbar hypermobility: where swimming becomes hydrotherapy].

    Science.gov (United States)

    Mergeay, D; De Neve, M

    1990-01-01

    In this paper the authors discuss the clinical problem of lumbar hypermobility. The therapeutical possibilities are resumed briefly. The philosophy of medical training therapy ("Heilgymnastik") is described. More extensive the extra-advantages of hydrotherapy (methodical back-stroke swimming) are searched for in a theoretical deductive way. The authors found that: 1. swimming is a low-impact sport so far as the articulations are concerned, 2. back-stroke is done mainly in a lumbar kyphosis, 3. swimming is also an excellent cardiopulmonary training, 4. when swimming the muscles of the shoulder girdle and pelvic girdle are trained in a nearly isokinetic way (power-endurance), 5. the short transverso-spinal muscles are indirectly trained in their tonic more than phasic stretch reflex (posture function), 6. the muscles of the trunk are trained in a nearly isometric way in the appropriate angles (erect position), 7. the position of the head in the water facilitates the abdominal muscles (tonic neck reflex), 8. the cool temperature of the water generates training-enhancing stress-responses, 9. endurance-training is ideal for the postural function of the lower back muscles (especially the deeper layers near the spine) which are anatomical and physiological suited for this purpose, 10. warming-up and cooling-down procedures prepare the neuromuscular, the cardiovascular and metabolic functions before the workout-session (a cold shower afterwards acts to tonicize the skin and muscles).

  9. Sinusoidal cycling swimming pattern of reservoir fishes

    Czech Academy of Sciences Publication Activity Database

    Čech, Martin; Kubečka, Jan

    2002-01-01

    Roč. 61, č. 2 (2002), s. 456-471 ISSN 0022-1112 R&D Projects: GA AV ČR IAA6017901; GA AV ČR IAA6017201; GA ČR GA206/02/0520 Keywords : sinusoidal swimming * echosounder * reservoir Subject RIV: EH - Ecology, Behaviour Impact factor: 1.186, year: 2002

  10. Extreme swimming: The oceanic migrations of anguillids

    DEFF Research Database (Denmark)

    Righton, David; Aarestrup, Kim; Jellyman, Don

    2013-01-01

    to their natal habitat to spawn. In temperate species, the migrations are extreme, requiring larvae and adults to swim thousands of km before reaching their destination, but the migrations of tropical species (hundreds of km) are still remarkable in comparison with many other fish species. To achieve...

  11. 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.

  12. Effect of dielectrophoretic force on swimming bacteria.

    Science.gov (United States)

    Tran, Ngoc Phu; Marcos

    2015-07-01

    Dielectrophoresis (DEP) has been applied widely in bacterial manipulation such as separating, concentrating, and focusing. Previous studies primarily focused on the collective effects of DEP force on the bacterial population. However, the influence of DEP force on the swimming of a single bacterium had not been investigated. In this study, we present a model to analyze the effect of DEP force on a swimming helically flagellated bacterium, particularly on its swimming direction and velocity. We consider a simple DEP force that acts along the X-direction, and its strength as well as direction varies with the X- and Y-positions. Resistive force theory is employed to compute the hydrodynamic force on the bacterium's flagellar bundle, and the effects of both DEP force and rotational diffusion on the swimming of the bacterium are simultaneously taken into consideration using the Fokker-Planck equation. We show the mechanism of how DEP force alters the orientation and velocity of the bacterium. In most cases, the DEP force dominantly influences the orientation of the swimming bacterium; however, when the DEP force strongly varies along the Y-direction, the rotational diffusion is also responsible for determining the bacterium's reorientation. More interestingly, the variance of DEP force along the Y-direction causes the bacterium to experience a translational velocity perpendicular to its primary axis, and this phenomenon could be utilized to focus the bacteria. Finally, we show the feasibility of applying our findings to achieve bacterial focusing. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Model of large pool fires

    International Nuclear Information System (INIS)

    Fay, J.A.

    2006-01-01

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables

  14. Medical device disinfection by dense carbon dioxide.

    Science.gov (United States)

    Bertoloni, G; Bertucco, A; Rassu, M; Vezzù, K

    2011-01-01

    The employment of disinfection-sterilisation processes for the re-use of medical devices without negative effects such as the presence of toxic residues, material degradation or other modifications is an important consideration for reducing the costs of surgical and medical procedures. Ethylene oxide is the most commonly used low temperature sterilisation technique in healthcare facilities, but its associated toxicity has reduced interest in this technology for the reprocessing of medical equipment. The aim of this study was to examine the disinfection efficiency of a novel low temperature approach, based on dense carbon dioxide on artificially contaminated catheters. The results obtained demonstrated that this method provided a complete inactivation of all bacteria and yeast strains tested, and that no obvious modifications to the surfaces tested were observed with multiple treatments. Copyright © 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

  15. Is free halogen necessary for disinfection?

    Science.gov (United States)

    Williams, D E; Elder, E D; Worley, S D

    1988-10-01

    The principle of Le Chatelier was used in demonstrating that 3-chloro-4,4-dimethyl-2-oxazolidinone (compound 1) itself kills Staphylococcus aureus rather than the very small amount of free chlorine in hydrolysis equilibrium with compound 1. On the other hand, when the N-bromo analog of compound 1 (compound 1B) was used as the disinfectant, the mixture of combined compound 1B and free bromine formed in the hydrolysis equilibrium provided disinfection. When the hydrolysis equilibrium for 1B was suppressed to the level at which a negligible amount of free bromine remained in solution, combined compound 1B was much more efficacious than combined compound 1 at killing S. aureus.

  16. Water disinfecting; Desinfection d'eau

    Energy Technology Data Exchange (ETDEWEB)

    Parisot, F

    2009-04-15

    The Soxitis equipment is an innovating alternative to the use of chemical products for disinfecting cooling tower circuits. This equipment is based on a higher temperature electrolysis of the salt molecules contained in water. Present electrodes (titanium, tungsten, silver, copper or gold) used in similar systems are limited in voltage to 1.5 V. The Soxitis electrode can sustain 3 V which enlarges the spectrum of chemical reactions: chloride, ozone, hydrogen peroxide, persulfates, per-carbonates and hydroxide radicals are produced. The combining effect of all these products generates a disinfecting effect 4 times as high as chloride alone. As a consequence Soxitis uses 4 times less salt than present equipment and releases less corrosive water in the system. (A.C.)

  17. Assessment of photoreactivation following ultraviolet light disinfection

    International Nuclear Information System (INIS)

    Kashimada, K.; Kamiko, N.; Yamamoto, K.; Ohgaki, S.

    1996-01-01

    Photoreactivation of microorganisms following UV disinfection is one of the research topics of interest in assessing the performance of UV disinfection, because there is little consensus on how the visible light intensity relates to the photoreactivation rate and the maximum survival in wastewater treatment processes. Apparent photoreactivation by a fluorescent lamp was observed in case of indicator bacteria (heterotrophic bacteria, coliform bacteria, fecal coliforms) in raw sewage, but not E. coli B and E. coli K12 A/λ(F+). Inactivation of fecal coliform was observed simultaneously during photoreactivation process by sunlight. Dose rate at 360 nm wave length as visible light intensity showed that it was a useful indicator for assessing the photoreactivation rate and the maximum survival when photoreactivation took place by both fluorescent lamp and sunlight. The model for photoreactivation was developed. The photoreactivation rate increased with increasing visible light intensity at 360 nm. However, the maximum survival value may not be affected by visible light intensity. (author)

  18. Microbiological Analysis in Three Diverse Natural Geothermal Bathing Pools in Iceland

    Science.gov (United States)

    Thorolfsdottir, Berglind Osk Th.; Marteinsson, Viggo Thor

    2013-01-01

    Natural thermal bathing pools contain geothermal water that is very popular to bathe in but the water is not sterilized, irradiated or treated in any way. Increasing tourism in Iceland will lead to increasing numbers of bath guests, which can in turn affect the microbial flora in the pools and therefore user safety. Today, there is no legislation that applies to natural geothermal pools in Iceland, as the water is not used for consumption and the pools are not defined as public swimming pools. In this study, we conducted a microbiological analysis on three popular but different natural pools in Iceland, located at Lýsuhóll, Hveravellir and Landmannalaugar. Total bacterial counts were performed by flow cytometry, and with plate count at 22 °C, 37 °C and 50 °C. The presence of viable coliforms, Enterococcus spp. and pseudomonads were investigated by growth experiments on selective media. All samples were screened for noroviruses by real time PCR. The results indicate higher fecal contamination in the geothermal pools where the geothermal water flow was low and bathing guest count was high during the day. The number of cultivated Pseudomonas spp. was high (13,000–40,000 cfu/100 mL) in the natural pools, and several strains were isolated and classified as opportunistic pathogens. Norovirus was not detected in the three pools. DNA was extracted from one-liter samples in each pool and analyzed by partial 16S rRNA gene sequencing. Microbial diversity analysis revealed different microbial communities between the pools and they were primarily composed of alpha-, beta- and gammaproteobacteria. PMID:23493033

  19. 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

  20. UV DISINFECTION GUIDANCE MANUAL FOR THE ...

    Science.gov (United States)

    Provides technical information on selection, design and operation of UV systems; provides regulatory agencies with guidance and the necessary tools to assess UV systems at the design, start-up, and routine operation phase; provides manufacturers with the testing and performance standards for UV components and systems for treating drinking water. Provide guidance to water systems, regulators and manufacturers on UV disinfection of drinking water.

  1. Adaptive Mechanisms Underlying Microbial Resistance to Disinfectants

    Science.gov (United States)

    2016-02-01

    ammonium compounds RTU SDS-PAGE ready-to- use sodium dodecyl (lauryl) sulfate-polyacrylamide gel electrophoresis SNP single nucleotide polymorphism TSB...resistance to Lysol, an all-purpose cleaner and disinfectant (U.S. Environmental Protection Agency regulation no. 777-89 [ready-to- use (RTU) 1:16...dilution]). A clinical surrogate, Escherichia coli, was used in these studies. E. coli cells were grown in the absence or presence of Lysol. The parent

  2. Disinfection of secondary effluents by infiltration percolation.

    Science.gov (United States)

    Makni, H

    2001-01-01

    Among the most attractive applications of reclaimed wastewater are: irrigation of public parks, sports fields, golf courses and market gardening. These uses require advanced wastewater treatment including disinfection. According to WHO guidelines (1989) and current rules and regulations in Tunisia, faecal coliform levels have to be reduced to < 10(3) or 10(2) CFU/100 mL. In Tunisia, most wastewater plants are only secondary treatment and, in order to meet health related regulations, the effluents need to be disinfected. However, it is usual for secondary effluents to need filtration prior to disinfection. Effectiveness of conventional disinfection processes, such as chlorination and UV radiation, are dependent upon the oxidation level and the levels of suspended solids of the treated water. Ozonation is relatively expensive and energy consuming. The consideration of the advantages and disadvantages of conventional techniques, their reliability, investment needs and operational costs will lead to the use of less sophisticated alternative techniques for certain facilities. Among alternative techniques, soil aquifer treatment and infiltration percolation through sand beds have been studied in Arizona, Israel, France, Spain and Morocco. Infiltration percolation plants have been intermittently fed with secondary or high quality primary effluents which percolated through 1.5-2 m unsaturated coarse sand and were recovered by under-drains. In such infiltration percolation facilities, microorganisms were eliminated through numerous physical, physicochemical and biological inter-related processes (mechanical filtration, adsorption and microbial degradation respectively). Efficiency of faecal coliform removal was dependent upon the water detention times in the filtering medium and on the oxidation of the filtered water. Effluents of Sfax town aerated ponds were infiltrated through 1.5 m deep sand columns in order to determine the performance of infiltration percolation in the

  3. Energetics of median and paired fin swimming, body and caudal fin swimming, and gait transition in parrotfish (Scarus schlegeli) and triggerfish (Rhinecanthus aculeatus)

    DEFF Research Database (Denmark)

    Korsmeyer, Keith E; Steffensen, John Fleng; Herskin, Jannik

    2002-01-01

    To determine the energetic costs of rigid-body, median or paired-fin (MPF) swimming versus undulatory, body-caudal fin (BCF) swimming, we measured oxygen consumption as a function of swimming speed in two MPF swimming specialists, Schlegel's parrotfish and Picasso triggerfish. The parrotfish swam.......1 L s(-1) (30 min U(crit)). In both species, the rates of increase in oxygen consumption with swimming speed were higher during BCF swimming than during rigid-body MPF swimming. Our results indicate that, for these species, undulatory swimming is energetically more costly than rigid-body swimming......, and therefore support the hypothesis that MPF swimming is more efficient. In addition, use of the BCF gait at higher swimming speed increased the cost of transport in both species beyond that predicted for MPF swimming at the same speeds. This suggests that, unlike for terrestrial locomotion, gait transition...

  4. 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.

  5. Evaluation of toothbrush disinfection via different methods

    Directory of Open Access Journals (Sweden)

    Adil BASMAN

    2016-01-01

    Full Text Available The aim of this study was to compare the efficacy of using a dishwasher or different chemical agents, including 0.12% chlorhexidine gluconate, 2% sodium hypochlorite (NaOCl, a mouthrinse containing essential oils and alcohol, and 50% white vinegar, for toothbrush disinfection. Sixty volunteers were divided into five experimental groups and one control group (n = 10. Participants brushed their teeth using toothbrushes with standard bristles, and they disinfected the toothbrushes according to instructed methods. Bacterial contamination of the toothbrushes was compared between the experimental groups and the control group. Data were analyzed by Kruskal–Wallis and Duncan's multiple range tests, with 95% confidence intervals for multiple comparisons. Bacterial contamination of toothbrushes from individuals in the experimental groups differed from those in the control group (p < 0.05. The most effective method for elimination of all tested bacterial species was 50% white vinegar, followed in order by 2% NaOCl, mouthrinse containing essential oils and alcohol, 0.12% chlorhexidine gluconate, dishwasher use, and tap water (control. The results of this study show that the most effective method for disinfecting toothbrushes was submersion in 50% white vinegar, which is cost-effective, easy to access, and appropriate for household use.

  6. Biological Treatment of Water Disinfection Byproducts using ...

    Science.gov (United States)

    Major disinfection by-products (DBPs) from the chlorination process of drinking water include trihalomethanes (THMs) and haloacetic acides (HAA5). THMs mainly consist of chloroform, and other harsh chemicals. Prolonged consumptions of drinking water containing high levels of THMs has been linked with diseases of the liver, kidneys, bladder, or central nervous system and may increase likelihood of cancer. A risk also exists for THMs exposure via inhalation while showering, bathing or washing clothes and dishes. Due to these risks, the U.S. EPA regulate THMs content in drinking water. This research investigates biological degradation of THM using chloroform as a model compound. The study aims to decrease possible risks of THMs through filtration. Throughout this year’s presentations, there is a common theme of health and safety concerns. UC researchers are working hard to clean water ways of naturally occurring contaminates as well as man-made toxins found in our waterways. The significance of these presentations translates into the promise of safer environments, and more importantly saved lives, as UC’s faculty continues to produce real-world solutions to problems threatening the world around us. A biotech process has been developed and demonstrated that effectively remove and treat volatile disinfection by-products from drinking water. The process strips low concentration disinfection by-products, such as trihalomethanes, that are formed during the chlori

  7. Airborne Microorganism Disinfection by Photocatalytic HEPA Filter

    Directory of Open Access Journals (Sweden)

    Rotruedee Chotigawin

    2010-07-01

    Full Text Available This study determined the efficacy of photocatalytic HEPA filters on microorganism disinfection in a closed-loop chamber and later applied it in an air purifier and tested its efficacy in an 8-m3 chamber and in a hospital. The photocatalytic filters were made by dip-coating a HEPA filter in a TiO2 slurry. In order to disinfect the microorganisms retained on the filter, UV-A light was irradiated onto the filter to create strong oxidative radicals which can destroy microorganisms. The findings showed that disinfection efficiency of the photocatalytic filters with high TiO2 loading was insignificantly higher than with lower loading. S. epidermidis was completely eliminated within 2 hours, while 86.8% of B. subtilis, 77.1% of A. niger, and 82.7% of P. citrinum were destroyed within 10 hours. When applying the photocatalytic filters into an air purifier in a 8-m3 chamber, it was found that as soon as the air purifier was turned on, 83.4% of S. epidermidis, 81.4% of B. subtilis, 88.5% of A. niger, and 75.8% of P. citrinum were removed from the air. In a hospital environment, the PCO air purifier efficacy was lower than that in the chamber. Besides, relative humidity, distances from the air purifier and room size were suspected to affect the efficacy of the photocatalytic filters.

  8. New Technologies to Improve Root Canal Disinfection.

    Science.gov (United States)

    Plotino, Gianluca; Cortese, Teresa; Grande, Nicola M; Leonardi, Denise P; Di Giorgio, Gianni; Testarelli, Luca; Gambarini, Gianluca

    2016-01-01

    Effective irrigant delivery and agitation are prerequisites to promote root canal disinfection and debris removal and improve successful endodontic treatment. This paper presents an overview of the currently available technologies to improve the cleaning of the endodontic space and their debridement efficacy. A PubMed electronic search was conducted with appropriate key words to identify the relevant literature on this topic. After retrieving the full-text articles, all the articles were reviewed and the most appropriate were included in this review. Several different systems of mechanical activation of irrigants to improve endodontic disinfection were analysed: manual agitation with gutta-percha cones, endodontic instruments or special brushes, vibrating systems activated by low-speed hand-pieces or by sonic or subsonic energy, use of ultrasonic or laser energy to mechanically activate the irrigants and apical negative pressure irrigation systems. Furthermore, this review aims to describe systems designed to improve the intracanal bacterial decontamination by a specific chemical action, such as ozone, direct laser action or light-activated disinfection. The ultrasonic activation of root canal irrigants and of sodium hypochlorite in particular still remains the gold standard to which all other systems of mechanical agitation analyzed in this article were compared. From this overview, it is evident that the use of different irrigation systems can provide several advantages in the clinical endodontic outcome and that integration of new technologies, coupled with enhanced techniques and materials, may help everyday clinical practice.

  9. UV disinfection of soluble oil metalworking fluids.

    Science.gov (United States)

    Johnson, David L; Phillips, Margaret L

    2002-01-01

    The efficacy of a new high-intensity germicidal ultraviolet (UV) lamp for disinfection of opaque metalworking fluids (MWF) was investigated under laboratory conditions. Three dilutions of "soluble oil" MWF and water controls in a circulating system were inoculated with suspensions of Pseudomonas fluorescens to an initial concentration of about 10(7) colony forming units (CFU) per milliliter and irradiated with a submerged nonglass UV lamp. Aliquots of the circulating fluid were withdrawn before irradiation and at 10-sec intervals in the water control and 10-min intervals in the MWF. The samples were diluted with sterile water, plated, and counted after 18-24 hours' incubation. The UV-C radiation output of the lamp was estimated by irradiance measurements using a research radiometer. The concentration of CFU decreased by at least 2 logs (>99% reduction in culturability) in 30 sec in irradiated water. In all three dilutions of MWF, a 2-log decrease was obtained within 60 min. The UV-C output of the lamp was estimated at about 6 W. The disinfection appeared to follow a first order rate law both in MWF and in water. The CFU concentration was stable over time in unirradiated controls. These results demonstrate that UV disinfection is feasible in MWF opaque to both visible and UV wavelengths of light.

  10. Spiral-shaped reactor for water disinfection

    KAUST Repository

    Soukane, Sofiane

    2016-04-20

    Chlorine-based processes are still widely used for water disinfection. The disinfection process for municipal water consumption is usually carried out in large tanks, specifically designed to verify several hydraulic and disinfection criteria. The hydrodynamic behavior of contact tanks of different shapes, each with an approximate total volume of 50,000 m3, was analyzed by solving turbulent momentum transport equations with a computational fluid dynamics code, namely ANSYS fluent. Numerical experiments of a tracer pulse were performed for each design to generate flow through curves and investigate species residence time distribution for different inlet flow rates, ranging from 3 to 12 m3 s−1. A new nature-inspired Conch tank design whose shape follows an Archimedean spiral was then developed. The spiral design is shown to strongly outperform the other tanks’ designs for all the selected plug flow criteria with an enhancement in efficiency, less short circuiting, and an order of magnitude improvement in mixing and dispersion. Moreover, following the intensification philosophy, after 50% reduction in its size, the new design retains its properties and still gives far better results than the classical shapes.

  11. Disinfectant effect of Methylated Ethanol against Listeria species

    OpenAIRE

    Y Yakubu; M D Salihu; O O Faleke; M B Abubakar; A A Magaji,A U Junaidu

    2012-01-01

    This study was carried out in order to determine the disinfectant effect of Methylated spirit® (95% methanol and 5% ethanol) as a teat dip against Listeria species. Hand milking was employed to collect 576 (288 x 2) raw milk samples from different lactating cows within Sokoto metropolis (Nigeria). 288 samples were collected before disinfecting the udder teats with Methylated spirit®, while the other 288 were collected after disinfection with Methylated spirit®. The ...

  12. 40 CFR 141.709 - Developing the disinfection profile and benchmark.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for... water must be measured at each residual disinfectant concentration sampling point during peak hourly... disinfected water must be measured at each chlorine residual disinfectant concentration sampling point during...

  13. Elite sprint swimming performance is enhanced by completion of additional warm-up activities.

    Science.gov (United States)

    McGowan, Courtney J; Pyne, David B; Thompson, Kevin G; Raglin, John S; Osborne, Mark; Rattray, Ben

    2017-08-01

    This study investigated the effect of completing additional warm-up strategies in the transition phase between the pool warm up and the start of a race on elite sprint swimming performance. Twenty-five elite swimmers (12 men, 20 ± 3 years; 13 women, 20 ± 2 years, performance standard ~807 FINA2014 points) completed a standardised pool warm up followed by a 30-min transition phase and a 100-m freestyle time trial. During the transition phase, swimmers wore a tracksuit jacket with integrated heating elements and performed a dry land-based exercise routine (Combo), or a conventional tracksuit and remained seated (Control). Start (1.5% ± 1.0%, P = 0.02; mean ± 90% confidence limits) and 100-m time trial (0.8% ± 0.4%, P heating via heated jackets and completion of dry land-based exercises in the transition phase improves elite sprint swimming performance by ~0.8%.

  14. Effects of skin disinfection method, deviation bag, and bacterial screening on clinical safety of platelet transfusions in the Netherlands.

    Science.gov (United States)

    de Korte, Dirk; Curvers, Joyce; de Kort, Wim L A M; Hoekstra, Tiny; van der Poel, Cees L; Beckers, Erik A M; Marcelis, Jan H

    2006-03-01

    Bacterial contamination of blood products is a great hazard for development of fatal transfusion reactions. Bacterial screening of platelet concentrates (PC) by aerobic and anaerobic culturing (BacT/ALERT, bioMérieux) was introduced in the Netherlands in October 2001. In November 2002, a nationwide, uniform skin cleansing method was introduced with a double-swab disinfection with 70 percent isopropyl alcohol. One location routinely used an integrated diversion bag to collect the first 20 to 30 mL. Over the calendar years 2002 and 2003, in total 113,093 PCs derived from pooled buffy coats were screened. After introduction of the new disinfection method, 0.85 percent were initially positive. This was a small reduction compared to the previous disinfection methods under which 0.95 percent were initially positive. The location with use of the diversion bag showed a significantly lower frequency of bacterial contamination, with 0.50 percent before and 0.37 percent after introduction of 70 percent isopropyl alcohol. In addition 8000 apheresis PCs were also screened, showing 24 initially positive samples (0.30%). The use of the diversion bag and, to a lesser extent, the use of double swabs with 70 percent isopropyl alcohol, led to a reduction of contamination. As expected, predominant contamination with resident skin bacteria was reduced. The combination of diversion bag and new disinfection led to a frequency of initial positive results for pooled five-donor PCs, which is similar to that of single-donor apheresis PCs. Furthermore, the bacterial detection system and associated product recall procedures have been shown to be effective in preventing transfusion of contaminated PCs and/or related red cells, especially for rapidly growing bacteria.

  15. 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.

  16. Addition of fraction in swimming context

    Science.gov (United States)

    Putri, R. I. I.; Gunawan, M. S.; Zulkardi

    2017-12-01

    This study aimed to produce learning trajectory that can help students in learning fractions by using swimming context. The study involved 37 fourth grade students with different capabilities in Elementary School IBA, South Sumatra, Indonesia. This study used an instructional theory called Indonesian version of Realistic Mathematics Education (PMRI). This research used design research method with three stages: preliminary design, the design experiment, and retrospective analysis. Several techniques used for collecting data including a video recording of students interaction in the group discussion, students’ work, and interviewing the students. To conclude, the swimming context could stimulate students’ informal knowledge about the meaning of fractions in which it can be used in the additional learning either the same denominator or different denominator.

  17. Spent fuel storage pool and reactor well pool

    International Nuclear Information System (INIS)

    Fuchisawa, Hiroshi.

    1996-01-01

    An overflow device is disposed to a water draining channel communicating a spent fuel storage pool, a well pool and a cask cleaning pit, and a cleaning treatment system is connected to the cask cleaning pit. In addition, a tank chamber having an overflow device communicating with the well pool is disposed to the inside of the spent fuel storage pool, and a cleaning system is connected to the tank chamber. Namely, water overflow from the spent fuel storage pool and the well pool flows down to the cask cleaning pit directly, the water level can be kept to a predetermined value without disposing a skimmer serge tank, and the overflow water is transported to and cleaned in the cleaning treatment system. In addition, the overflow water flow to the tank chamber directly is transferred to and cleaned in the cleaning treatment system. The cost for the reactor building can be reduced, and interference with the building and adjustment for the steps upon installation of the skimmer serge tank are no more necessary to shorten the terms for the building construction. (N.H.)

  18. 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.

  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. Anaerobic critical velocity in four swimming techniques.

    Science.gov (United States)

    Neiva, H P; Fernandes, R J; Vilas-Boas, J P

    2011-03-01

    The aim of this study was to assess critical velocity in order to control and evaluate anaerobic swimming training. 51 highly trained male swimmers performed maximal 15, 25, 37.5 and 50 m in the 4 swimming techniques to determine critical velocity from the distance-time relationship. Anaerobic critical velocity was compared with 100 m swimming performance and corresponding partials. Complementarily, 9 swimmers performed a 6×50 m (4 min interval) training series at front crawl individual anaerobic critical velocity, capillary blood lactate concentrations being assessed after each repetition. The mean±SD values of anaerobic critical velocity and its relationship with the 100 m event were: 1.61±0.07 (r=0.60, p=0.037), 1.53±0.05 (r=0.81, p=0.015), 1.33±0.05 (r=0.83, p=0.002), and 1.75±0.05 (r=0.74, p=0.001), for butterfly, backstroke, breaststroke and front crawl, respectively. However, differences between anaerobic critical velocity and performance were observed (with exception of the second half of the 100 m swimming events in breaststroke and butterfly). Lactate concentration values at the end of the series were 14.52±1.06 mmol.l (-1), which suggests that it was indeed an anaerobic training set. In this sense, anaerobic critical velocity can be used to prescribe anaerobic training intensities. © Georg Thieme Verlag KG Stuttgart · New York.

  2. Propulsive force symmetry generated during butterfly swimming

    Directory of Open Access Journals (Sweden)

    Gustavo Soares Pereira

    2015-12-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n6p704   The aim of the study was to analyze the hand force symmetry in butterfly swimming. Fourteen male and female swimmers (18.4 ± 4.9 years old, 71.8 ± 14.6 kg of body mass, 1.78 ± 0.09 m of height and mean performance that corresponds to 74.9 ± 5.8% of the world record. Subjects performed three trials of 25 m of butterfly swimming at maximal speed. Mean and maximum forces were estimated for each hand using pressure sensors of the Aquanex System (Swimming Technology Research, USA. The comparisons between force values for dominant and non-dominant hands were made through Student’s T test for dependent samples (p<0.05. In addition, the symmetry Index (SI was calculated as a relative measure of the force applied by each hand. The mean and maximum force for the dominant hand corresponded, respectively, to 55.7 ± 14.7 N and 114.7 ± 39.6 N. For the non-dominant hand, values were 51.2 ± 14.7 N for mean force and 110.7 ± 36.7 N for maximum force. Significant differences were found between dominant and non-dominant hands for both variables (p<0.01. The symmetry index analysis showed mean values of 8.9% for mean force and of 12.6% for maximum force, and most swimmers presented values higher than 10% for mean and/or maximum forces. Further studies should be performed in order to investigate the relationship between hand force symmetry and swimming performance.

  3. Swimming Three Ice Miles within Fifteen Hours.

    Science.gov (United States)

    Stjepanovic, Mirko; Nikolaidis, Pantelis T.; Knechtle, Beat

    2017-08-31

    Ice Mile swimming (1608 m in water of below 5 °Celsius) is becoming increasingly popular. This case study aimed to identify body core temperature and selected haematological and biochemical parameters before and after repeated Ice Miles. An experienced ice swimmer completed three consecutive Ice Miles within 15 h. Swim times, body core temperatures, and selected urinary and haematological parameters were recorded. Body core temperature reached its maximum between 5, 8 and 15 min after immersion (37.7°C, 38.1°C, and 38.0°C, respectively). The swimmer suffered hypothermia during the first Ice Mile (35.4°C) and body core temperature dropped furthermore to 34.5°C during recovery after the first Ice Mile. He developed a metabolic acidosis in both the first and the last Ice Mile (pH 7.31 and pH 7.34, respectively). We observed hyperkalaemia ([K⁺] > 5.5 mM) after the second Ice Mile (6.9 mM). This was followed by a drop in [K⁺] to3.7 mM after the third Ice Mile. Anticipatory thermogenesis (i.e. an initial increase of body core temperature after immersion in ice cold water) seems to be a physiological response in a trained athlete. The results suggest that swimming in ice-cold water leads to a metabolic acidosis, which the swimmer compensates with hyperventilation (i.e. leading to respiratory alkalosis). The shift of serum [K⁺] could increase the risk of a cardiac arrhythmia. Further studies addressing the physiology and potential risks of Ice Mile swimming are required to substantiate this finding.

  4. Swimming in a granular frictional fluid

    Science.gov (United States)

    Goldman, Daniel

    2012-02-01

    X-ray imaging reveals that the sandfish lizard swims within granular media (sand) using axial body undulations to propel itself without the use of limbs. To model the locomotion of the sandfish, we previously developed an empirical resistive force theory (RFT), a numerical sandfish model coupled to an experimentally validated Discrete Element Method (DEM) model of the granular medium, and a physical robot model. The models reveal that only grains close to the swimmer are fluidized, and that the thrust and drag forces are dominated by frictional interactions among grains and the intruder. In this talk I will use these models to discuss principles of swimming within these granular ``frictional fluids". The empirical drag force laws are measured as the steady-state forces on a small cylinder oriented at different angles relative to the displacement direction. Unlike in Newtonian fluids, resistive forces are independent of speed. Drag forces resemble those in viscous fluids while the ratio of thrust to drag forces is always larger in the granular media than in viscous fluids. Using the force laws as inputs, the RFT overestimates swimming speed by approximately 20%. The simulation reveals that this is related to the non-instantaneous increase in force during reversals of body segments. Despite the inaccuracy of the steady-state assumption, we use the force laws and a recently developed geometric mechanics theory to predict optimal gaits for a model system that has been well-studied in Newtonian fluids, the three-link swimmer. The combination of the geometric theory and the force laws allows us to generate a kinematic relationship between the swimmer's shape and position velocities and to construct connection vector field and constraint curvature function visualizations of the system dynamics. From these we predict optimal gaits for forward, lateral and rotational motion. Experiment and simulation are in accord with the theoretical prediction, and demonstrate that

  5. Volumetric flow around a swimming lamprey

    Science.gov (United States)

    Lehn, Andrea M.; Colin, Sean P.; Costello, John H.; Leftwich, Megan C.; Tytell, Eric D.

    2015-11-01

    A primary experimental technique for studying fluid-structure interactions around swimming fish has been planar dimensional particle image velocimetry (PIV). Typically, two components of the velocity vector are measured in a plane, in the case of swimming studies, directly behind the animal. While useful, this approach provides little to no insight about fluid structure interactions above and below the fish. For fish with a small height relative to body length, such as the long and approximately cylindrical lamprey, 3D information is essential to characterize how these fish interact with their fluid environment. This study presents 3D flow structures along the body and in the wake of larval lamprey, P etromyzon m arinus , which are 10-15 cm long. Lamprey swim through a 1000 cm3 field of view in a standard 10 gallon tank illuminated by a green laser. Data are collected using the three component velocimeter V3V system by TSI, Inc. and processed using Insight 4G software. This study expands on previous works that show two pairs of vortices each tail beat in the mid-plane of the lamprey wake. NSF DMS 1062052.

  6. Three-link Swimming in Sand

    Science.gov (United States)

    Hatton, R. L.; Ding, Yang; Masse, Andrew; Choset, Howie; Goldman, Daniel

    2011-11-01

    Many animals move within in granular media such as desert sand. Recent biological experiments have revealed that the sandfish lizard uses an undulatory gait to swim within sand. Models reveal that swimming occurs in a frictional fluid in which inertial effects are small and kinematics dominate. To understand the fundamental mechanics of swimming in granular media (GM), we examine a model system that has been well-studied in Newtonian fluids: the three-link swimmer. We create a physical model driven by two servo-motors, and a discrete element simulation of the swimmer. To predict optimal gaits we use a recent geometric mechanics theory combined with empirically determined resistive force laws for GM. We develop a kinematic relationship between the swimmer's shape and position velocities and construct connection vector field and constraint curvature function visualizations of the system dynamics. From these we predict optimal gaits for forward, lateral and rotational motion. Experiment and simulation are in accord with the theoretical predictions; thus geometric tools can be used to study locomotion in GM.

  7. 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.

  8. Favourable impact of regular swimming in young people with haemophilia: experience derived from 'Desafio del Caribe' project.

    Science.gov (United States)

    Boadas, A; Osorio, M; Gibraltar, A; Rosas, M M; Berges, A; Herrera, E; Gadea, S; Gutiérrez, M Á; Salazar, F; Ruiz-Sáez, A

    2015-01-01

    Swimming is beneficial for persons with haemophilia (PWH) providing good maintenance of the cardiovascular and musculoskeletal system and improving many psychological characteristics. In the Desafío del Caribe Project, young PWH from Venezuela and Mexico took part in an open water competition in the Gulf of Mexico under a multidisciplinary team supervision. Eight severe haemophilia A, two moderate haemophilia A, one severe haemophilia B and two moderate haemophilia B subjects were included. Haematological, musculoskeletal and psychological evaluations were carried out before and during training for the competition. Training program included physical exercise routines and swimming practices that alternated between pools and open water. Swimmers had coverage with factor concentrates before pool and open water trainings. In physiatric evaluations, the Hemophilia Joint Health Score (HJHS) was used. The objective of the psychology area was to analyse self-esteem, precompetition anxiety, coping mechanisms and relaxation levels. The need of factor prophylaxis before intense trainings was confirmed. In the musculoskeletal system a decrease of elbow pain as well as an increase of muscle strength in the ankles were observed. In the psychological area significant differences between the first and second test in self-esteem levels, cognitive anxiety and group cohesion were found. PWH must be provided with orientation and encouragement to practice swimming regularly. High competition exercise must be supervised by a multidisciplinary team which must evaluate the pros and cons of the activity to make relevant recommendations. © 2014 John Wiley & Sons Ltd.

  9. ENERGY STAR Certified Pool Pumps

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 1.1 ENERGY STAR Program Requirements for Pool Pumps that are effective as of February 15,...

  10. 76 FR 25236 - Carbon Dioxide; Exemption From the Requirement of a Tolerance

    Science.gov (United States)

    2011-05-04

    ... Departure/Levels of Concern Considering its presence in the environment and in the human body, the... exposure (e.g., textiles (clothing and diapers), carpets, swimming pools, and hard surface disinfection on...

  11. Sustainability of common pool resources

    OpenAIRE

    Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

    2017-01-01

    Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepales...

  12. Pool impacts of Leidenfrost drop

    Science.gov (United States)

    Darbois Texier, Baptiste; Maquet, Laurent; Dorbolo, Stephane; Dehandschoewercker, Eline; Pan, Zhao; Truscott, Tadd

    2015-11-01

    This work concerns the impact of a droplet made of a volatile liquid (typically HFE) on a pool of an other liquid (typically silicone oil) which temperature is above the boiling point of the drop. Depending on the properties of the two liquids and the impacting conditions, four different regimes are observed. For low impacting speeds, the droplet bounces on the surface of the bath and finally levitates above it in a Leidenfrost state. Such a regime occurs as soon as the pool temperature exceeds the boiling point of the drop. This observation means that there is no threshold in temperature for a Leidenfrost effect on a liquid surface contrary to the case of a solid substrate. For intermediate impacting velocities, the pinch-off of the surface of the pool entraps the drop in the liquid bulk. The entrapped drop is separated from the pool by a layer of its own vapour in a similar way of antibulles. For increasing impacting speeds, the vapour layer between the drop and the pool does not hold during the pinch-off event. The contact of the drop with the hot liquid provokes a sudden and intense evaporation. At very large impacting speeds, the drop rapidely contacts the pool, spreads and finally induces a hemi-spherical cavity. In the end, these four different regimes are summarized in a Froud-Weber diagram which boundaries are discussed.

  13. 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…

  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. Comparing irradiation parameters on disinfecting enterrecoccus faecalis in root canal disinfection

    Science.gov (United States)

    Sarp, Ayşe. S.; Gülsoy, Murat

    2016-02-01

    Although conventional method carries all the debris, studies on persisting infections in root canals show bacteria and their toxins spread from the root canal and contaminate the apical region. Thus developes apical periodontitis or symptoms, and loss of tooth. Even if the treatment has adequate success, anatomy of root canal system can be very complexwith accessory canals. The disinfecting effect of laser radiation has only recently been used in dentistry. Laser irradiation has a bactericidal effect. Each wavelength has its own advantages and limitations according to their different absorption characteristics, depending on their 'absorption coefficient'. The sterilizing efficiency of two types of wavelengths, a new fiber laser 1940- nm Thulium fiber Laser and an 2940 nm Er:YAG Laser were compared in this study. Irradiation with a power of 0.50 W with 1940- nm Thulium fiber Laser disinfected 95,15% of bacteria, however irradiation with same laser power with Er:YAG Laser caused a reduction of 96,48 %. But there was no significant difference in the disinfection effect of two different laser groups ( p < 0.05, Mann- U-Whitney Test). In addition to this, Er :YAG Laser caused three times more reduction from its own positive control group where 1940- nm Thulium fiber Laser caused 2,5 times effective disinfection.

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

    OpenAIRE

    Mwaffo, Violet; Zhang, Peng; Romero Cruz, Sebastián; Porfiri, Maurizio

    2017-01-01

    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 ...

  17. The swimming literacy of women in term sof self rescue

    OpenAIRE

    Vokurková, Eva

    2012-01-01

    Work name: The swimming literacy of women in term of self rescue Aim of work: To acquire and analyze data about the level of the swimming literacy and self rescue skills of women aged 18 - 72 years, whether they can handle and use them. Method: Literature search, creation of the questionnaire, implementation survey, data analysis and graphical presentation of results. Results: The analysis of the swimming literacy and self rescue skills of women. Key words: literacy, physical literacy, swimmi...

  18. Zero-G Condensing Heat Exchanger with Integral Disinfection

    Science.gov (United States)

    Burke, Kenneth A. (Inventor)

    2012-01-01

    The system that operates in a zero gravity environment and has an integral ozone generating capability is disclosed. The system contributes to the control of metabolic water vapors in the air, and also provided disinfection of any resulting condensate within the system, as well as disinfection of the air stream that flows throughout the disclosed system.

  19. In vitro antimicrobial activity of three new generation disinfectants ...

    African Journals Online (AJOL)

    Purpose: To determine the efficacies of three commercially available new generation disinfectants against some bacteria and yeast. Methods: Three commercially available new generation disinfectant (0.2 % chlorine dioxide, 0.3 % chlorine dioxide and 50 % hydrogen peroxide-stabilized by colloidal silver) were screened ...

  20. Disinfection studies of Nahar (Mesua ferrea) seed kernel oil using ...

    African Journals Online (AJOL)

    GREGORY

    2011-12-16

    Dec 16, 2011 ... kinetics. Heterotrophic plate count, using CFU/ml, pour plate method, 35°C / 48 h, plate count agar were employed to evaluate the disinfection and its ... Key words: Nahar (Mesua ferrea) seed kernel oil, extraction, gum Arabic, disinfection, kinetics. ..... Modeling of Chemical Kinetics and Reactor Design.

  1. Disinfectant effect of Methylated Ethanol against Listeria species

    Directory of Open Access Journals (Sweden)

    Y Yakubu

    2012-04-01

    Full Text Available This study was carried out in order to determine the disinfectant effect of Methylated spirit® (95% methanol and 5% ethanol as a teat dip against Listeria species. Hand milking was employed to collect 576 (288 x 2 raw milk samples from different lactating cows within Sokoto metropolis (Nigeria. 288 samples were collected before disinfecting the udder teats with Methylated spirit®, while the other 288 were collected after disinfection with Methylated spirit®. The samples were analyzed using selective culture and isolation technique in which the 288 samples collected before disinfection, 114 (39.6% were positive for Listeria species. Among the positive samples 44 (38.6% were Listeria innocua, 16 (14.0% Listeria ivanovii, 36 (31.6% Listeria monocytogenes, 11 (9.6% Listeria welshimeri and 7 (6.1% Listeria seeligeri, while none of the 288 samples collected after disinfection was positive. The study has shown high prevalence of Listeria species in milk collected without washing/disinfecting the teats and has also established the sensitivity of Listeria species to methylated ethanol which can be used as dip for disinfecting udder teats before milking in order to prevent contamination with Listeria species and other methylated spirit-sensitive organisms. This study is essential to educate Fulani herdsmen and other milk handlers on the importance of disinfecting udder teats before milking. [Vet. World 2012; 5(2.000: 91-93

  2. 21 CFR 880.6890 - General purpose disinfectants.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false General purpose disinfectants. 880.6890 Section... (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Miscellaneous Devices § 880.6890 General purpose disinfectants. (a) Identification. A general purpose...

  3. A practical evaluation of detergent and disinfectant solutions on ...

    African Journals Online (AJOL)

    Student01

    2012-01-06

    Jan 6, 2012 ... Combining disinfection studies, corrosion studies and the index of the two can assist the food and allied industries .... solutions was determined for three surfaces: aluminium (alloy. 5754) ..... Accelerated corrosion test results for lining surface materials and general usefulness of disinfectant for surfaces.

  4. Nanomaterial Case Study: Nanoscale Silver in Disinfectant Spray (Final Report)

    Science.gov (United States)

    EPA announced the release of the final report, Nanomaterial Case Study: Nanoscale Silver in Disinfectant Spray. This report represents a case study of engineered nanoscale silver (nano-Ag), focusing on the specific example of nano-Ag as possibly used in disinfectant spr...

  5. About sensititvity: salmonella biofi lms’ resistance to disinfectants action

    Directory of Open Access Journals (Sweden)

    V. F. Marievsky

    2013-10-01

    Full Text Available Salmonella biofi lms’ resistance to the action of the disinfectants was studied. It was founded that Salmonella biofi lms, which were formed on the hard carriers during 24 hours of incubation, demanded 32-fold increase of the minimal bactericide concentration of the disinfectant with quaternary ammonium compound.

  6. Microbial contamination of disinfectant solutions in some health care ...

    African Journals Online (AJOL)

    Commonly used disinfectants in some health institutions in three major towns of northern Nigeria were examined for presence of bacteria contamination. For each disinfectant, stock, freshly diluted and left-over of used diluted samples were analyzed. All the stock samples were free of bacteria contaminants while 52.17% of ...

  7. The antimicrobial activities of some commonly used disinfectants on ...

    African Journals Online (AJOL)

    The disinfectants; SavlonR, JikR, Methylated spirit and kerosene were observed for their inhibitory activities on Bacillus subtilis, Pseudomonas aeruginosa and Candida albicans. This was done by measuring the zone of inhibition of the disinfectants on the tested organisms. The results showed that Savlon was very effective ...

  8. Candida auris: Disinfectants and Implications for Infection Control

    Directory of Open Access Journals (Sweden)

    Tsun S. N. Ku

    2018-04-01

    Full Text Available Candida auris is a rapidly emerging pathogen and is able to cause severe infections with high mortality rates. It is frequently misidentified in most clinical laboratories, thus requiring more specialized identification techniques. Furthermore, several clinical isolates have been found to be multidrug resistant and there is evidence of nosocomial transmission in outbreak fashion. Appropriate infection control measures will play a major role in controlling the management and spread of this pathogen. Unfortunately, there are very few data available on the effectiveness of disinfectants against C. auris. Chlorine-based products appear to be the most effective for environmental surface disinfection. Other disinfectants, although less effective than chlorine-based products, may have a role as adjunctive disinfectants. A cleaning protocol will also need to be established as the use of disinfectants alone may not be sufficient for maximal decontamination of patient care areas. Furthermore, there are fewer data on the effectiveness of antiseptics against C. auris for patient decolonization and hand hygiene for healthcare personnel. Chlorhexidine gluconate has shown some efficacy in in vitro studies but there are reports of patients with persistent colonization despite twice daily body washes with this disinfectant. Hand hygiene using soap and water, with or without chlorhexidine gluconate, may require the subsequent use of alcohol-based hand sanitizer for maximal disinfection. Further studies will be needed to validate the currently studied disinfectants for use in real-world settings.

  9. [Scanning electron microscope study of chemically disinfected endodontic files].

    Science.gov (United States)

    Navarro, G; Mateos, M; Navarro, J L; Canalda, C

    1991-01-01

    Forty stainless steel endodontic files were observed at scanning electron microscopy after being subjected to ten disinfection cycles of 10 minutes each one, immersed in different chemical disinfectants. Corrosion was not observed on the surface of the files in circumstances that this study was made.

  10. 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.

  11. Morning Exercise: Enhancement of Afternoon Sprint-Swimming Performance.

    Science.gov (United States)

    McGowan, Courtney J; Pyne, David B; Thompson, Kevin G; Raglin, John S; Rattray, Ben

    2017-05-01

    An exercise bout completed several hours prior to an event may improve competitive performance later that same day. To examine the influence of morning exercise on afternoon sprint-swimming performance. Thirteen competitive swimmers (7 male, mean age 19 ± 3 y; 6 female, mean age 17 ± 3 y) completed a morning session of 1200 m of variedintensity swimming (SwimOnly), a combination of varied-intensity swimming and a resistance-exercise routine (SwimDry), or no morning exercise (NoEx). After a 6-h break, swimmers completed a 100-m time trial. Time-trial performance was faster in SwimOnly (1.6% ± 0.6, mean ± 90% confidence limit, P confidence limit], P = .04), body (0.2°C ± 0.1°C, P = .02), and skin temperatures (0.3°C ± 0.3°C, P = .02) were higher in SwimDry than in NoEx. Completion of a morning swimming session alone or together with resistance exercise can substantially enhance sprint-swimming performance completed later the same day.

  12. 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

  13. 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.

  14. Seismic analysis of large pools

    International Nuclear Information System (INIS)

    Dong, R.G.; Tokarz, F.J.

    1976-01-01

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated

  15. Seismic analysis of large pools

    Energy Technology Data Exchange (ETDEWEB)

    Dong, R.G.; Tokarz, F.J.

    1976-11-17

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated.

  16. Effectiveness of Four Disinfectants against Ebola Virus on Different Materials.

    Science.gov (United States)

    Smither, Sophie; Phelps, Amanda; Eastaugh, Lin; Ngugi, Sarah; O'Brien, Lyn; Dutch, Andrew; Lever, Mark Stephen

    2016-07-07

    The West Africa Ebola virus (EBOV) outbreak has highlighted the need for effective disinfectants capable of reducing viral load in a range of sample types, equipment and settings. Although chlorine-based products are widely used, they can also be damaging to equipment or apparatus that needs continuous use such as aircraft use for transportation of infected people. Two aircraft cleaning solutions were assessed alongside two common laboratory disinfectants in a contact kill assay with EBOV on two aircraft relevant materials representative of a porous and non-porous surface. A decimal log reduction of viral titre of 4 is required for a disinfectant to be deemed effective and two of the disinfectants fulfilled this criteria under the conditions tested. One product, Ardrox 6092, was found to perform similarly to sodium hypochlorite, but as it does not have the corrosive properties of sodium hypochlorite, it could be an alternative disinfectant solution to be used for decontamination of EBOV on sensitive apparatus.

  17. Recent advances in drinking water disinfection: successes and challenges.

    Science.gov (United States)

    Ngwenya, Nonhlanhla; Ncube, Esper J; Parsons, James

    2013-01-01

    Drinking water is the most important single source of human exposure to gastroenteric diseases, mainly as a result of the ingestion of microbial contaminated water. Waterborne microbial agents that pose a health risk to humans include enteropathogenic bacteria, viruses, and protozoa. Therefore, properly assessing whether these hazardous agents enter drinking water supplies, and if they do, whether they are disinfected adequately, are undoubtedly aspects critical to protecting public health. As new pathogens emerge, monitoring for relevant indicator microorganisms (e.g., process microbial indicators, fecal indicators, and index and model organisms) is crucial to ensuring drinking water safety. Another crucially important step to maintaining public health is implementing Water Safety Plans (WSPs), as is recommended by the current WHO Guidelines for Drinking Water Quality. Good WSPs include creating health-based targets that aim to reduce microbial risks and adverse health effects to which a population is exposed through drinking water. The use of disinfectants to inactivate microbial pathogens in drinking water has played a central role in reducing the incidence of waterborne diseases and is considered to be among the most successful interventions for preserving and promoting public health. Chlorine-based disinfectants are the most commonly used disinfectants and are cheap and easy to use. Free chlorine is an effective disinfectant for bacteria and viruses; however, it is not always effective against C. parvum and G. lamblia. Another limitation of using chlorination is that it produces disinfection by-products (DBPs), which pose potential health risks of their own. Currently, most drinking water regulations aggressively address DBP problems in public water distribution systems. The DBPs of most concern include the trihalomethanes (THMs), the haloacetic acids (HAAs), bromate, and chlorite. However, in the latest edition of the WHO Guidelines for Drinking Water Quality

  18. Disinfection of contaminated water by using solar irradiation.

    Science.gov (United States)

    Caslake, Laurie F; Connolly, Daniel J; Menon, Vilas; Duncanson, Catriona M; Rojas, Ricardo; Tavakoli, Javad

    2004-02-01

    Contaminated water causes an estimated 6 to 60 billion cases of gastrointestinal illness annually. The majority of these cases occur in rural areas of developing nations where the water supply remains polluted and adequate sanitation is unavailable. A portable, low-cost, and low-maintenance solar unit to disinfect unpotable water has been designed and tested. The solar disinfection unit was tested with both river water and partially processed water from two wastewater treatment plants. In less than 30 min in midday sunlight, the unit eradicated more than 4 log10 U (99.99%) of bacteria contained in highly contaminated water samples. The solar disinfection unit has been field tested by Centro Panamericano de Ingenieria Sanitaria y Ciencias del Ambiente in Lima, Peru. At moderate light intensity, the solar disinfection unit was capable of reducing the bacterial load in a controlled contaminated water sample by 4 log10 U and disinfected approximately 1 liter of water in 30 min.

  19. The role of surface disinfection in infection prevention

    Directory of Open Access Journals (Sweden)

    Gebel, Jürgen

    2013-04-01

    Full Text Available [english] Background: The Rudolf Schuelke Foundation addresses topics related to hygiene, infection prevention and public health. In this context a panel of scientists from various European countries discussed “The Role of Surface Disinfection in Infection Prevention”. The most important findings and conclusions of this meeting are summarised in the present consensus paper.Aim: Although the relevance of surface disinfection is increasingly being accepted, there are still a number of issues which remain controversial. In particular, the following topics were addressed: Transferral of microbes from surface to patients as a cause of infection, requirements for surface disinfectants, biocidal resistance and toxicity, future challenges.Methods and findings: After discussion and review of current scientific literature the authors agreed that contaminated surfaces contribute to the transmission of pathogens and may thus pose an infection hazard. Targeted surface disinfection based on a risk profile is seen as an indispensable constituent in a multibarrier approach of universal infection control precautions. Resistance and cross-resistance depend on the disinfectant agent as well as on the microbial species. Prudent implementation of surface disinfection regimens tested to be effective can prevent or minimize adverse effects.Conclusions: Disinfection must be viewed as a holistic process. There is a need for defining standard principles for cleaning and disinfection, for ensuring compliance with these principles by measures such as written standard operating procedures, adequate training and suitable audit systems. Also, test procedures must be set up in order to demonstrate the efficacy of disinfectants including new application methods such as pre-soaked wipes for surface disinfection.

  20. 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

  1. Profound Transcriptomic Differences Found between Sperm Samples from Sperm Donors vs. Patients Undergoing Assisted Reproduction Techniques Tends to Disappear after Swim-up Sperm Preparation Technique

    Directory of Open Access Journals (Sweden)

    Marcos Meseguer

    2010-01-01

    Full Text Available Background: Although spermatozoa delivers its RNA to oocytes at fertilization, its biologicalrole is not well characterized. Our purpose was to identify the genes differentially and exclusivelyexpressed in sperm samples both before and after the swim-up process in control donors andinfertile males with the purpose to identify their functional significance in male fertility.Materials and Methods: This was a nested case-control study. Ten sperm samples were obtainedfrom infertile patients [n=5 (two aliquots each from five samples; one before the swim-upprocess and one after] and donors [n=5 (two aliquots from five samples, one before the swim-upprocess and one after]. Oligonucleotide microarrays were employed to study the genome-wideexpression of pooled samples from infertile patients vs. donors. A total of four microarrays wereperfomed: two with sperm sample aliquots before swim-up and two with sperm samples aliquotsafter swim-up, from both the case and control groups. The results were evaluated to detect whichgenes expressed differentially [fold change (FC>5 and p<0.05] and which genes were exclusiveto each of the groups, both before and after swim-up.Results: Profound differences were detected between the fresh sperm samples of donors vs.infertile patients with respect to both differentially and exclusively expressed genes. Neverthelessthese differences seemed to decrease after the swim-up selection process.Conclusion: There are important differences between the expression profiles of sperm samplesof fertile donors vs. infertile patients who require assisted reproduction techniques (ART. Thesedifferences are potential forecasters of fertility success, although their reliability needs to beexplored further.

  2. Fine Sprays for Disinfection within Healthcare

    Directory of Open Access Journals (Sweden)

    G Nasr

    2016-09-01

    Full Text Available Problems exist worldwide with Hospital Acquired Infections (HAI's. The Spray Research Group (SRG have been working with relevant industries in developing a product which can provide a delivery system for treatment chemicals for surfaces, including the design and testing of a novel Spill-Return Atomiser (SRA for this purpose. A comprehensive description of this atomiser has already been given. This paper reports on a new application of this atomiser and discusses the problem of spray coating for disinfection that has been considered very little in previous work. The related spray coating performance tests in developing the product are thus provided. The experimental work includes determining the required spray duration and the coverage area produced by different sprays, including the analysis of the effects of atomiser positions, configurations, and the required number of atomisers. Comparison is made with the efficacy of an ultrasonic gas atomiser that is currently used for this purpose. The investigation has found that the utilisation of fine sprays (10μm>D32>25μm at high liquid pressure (<12MPa and low flow rates (<0.3 l/min is suitable for surface disinfection in healthcare applications (i.e. MRSA, VRSA etc.

  3. Chemical disinfection of combined sewer overflows

    DEFF Research Database (Denmark)

    Chhetri, Ravi Kumar

    of PFA, PAA and ClO2, a minimum dilution factor (590 times for PFA, 138 times for PAA and 700 times for ClO2) is needed for discharge into the surface water, to avoid the risk of toxic effect in the aquatic environment, albeit the rapid degradation of PFA and ClO2 in water will not have an acute toxic...... effect, and lower dilution factors may also be safe for the receiving waters. PFA and PAA were applied for the full-scale disinfection of CSO in two different Danish CSO structures. In the first CSO events, 2-8 mg/L PFA with 20 minutes’ contact time efficiently reduced E. coli and Enterococcus spp below...... directive 2006/7/EC. Nordic countries have a short summer season, and the frequent closures of harbour bathing areas in prime weeks for recreational activities are due mainly to the discharge of untreated CSO. Disinfecting a CSO in the existing CSO structure, before discharging it to the surface water...

  4. Energetics of median and paired fin swimming, body and caudal fin swimming, and gait transition in parrotfish (Scarus schlegeli) and triggerfish (Rhinecanthus aculeatus)

    DEFF Research Database (Denmark)

    Korsmeyer, Keith E; Steffensen, John Fleng; Herskin, Jannik

    2002-01-01

    , and therefore support the hypothesis that MPF swimming is more efficient. In addition, use of the BCF gait at higher swimming speed increased the cost of transport in both species beyond that predicted for MPF swimming at the same speeds. This suggests that, unlike for terrestrial locomotion, gait transition......To determine the energetic costs of rigid-body, median or paired-fin (MPF) swimming versus undulatory, body-caudal fin (BCF) swimming, we measured oxygen consumption as a function of swimming speed in two MPF swimming specialists, Schlegel's parrotfish and Picasso triggerfish. The parrotfish swam...... exclusively with the pectoral fins at prolonged swimming speeds up to 3.2 total lengths per second (L s(-1); 30 min critical swimming speed, U(crit)). At higher speeds, gait transferred to a burst-and-coast BCF swimming mode that resulted in rapid fatigue. The triggerfish swam using undulations of the soft...

  5. 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

    of reproductive traits, pectoral fin use and burse-assisted swimming on swimming metabolic rate, standard metabolic rate (MO2std) and prolonged swimming performance (Ucrit). Reproductive traits included reproductive allocation and pregnancy stage, the former defined as the mass of the reproductive tissues divided...... 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...... effects of pectoral fin use on swimming cost and Ucrit. Poecilia reticulata employed body-caudal fin (BCF) swimming at all tested swimming speeds; however, fish with a high simultaneous use of the pectoral fins exhibited increased swimming cost and decreased Ucrit. These data indicated that combining BCF...

  6. 40 CFR 141.533 - What data must my system collect to calculate a disinfection profile?

    Science.gov (United States)

    2010-07-01

    ... calculate a disinfection profile? 141.533 Section 141.533 Protection of Environment ENVIRONMENTAL PROTECTION... Filtration and Disinfection-Systems Serving Fewer Than 10,000 People Disinfection Profile § 141.533 What data must my system collect to calculate a disinfection profile? Your system must monitor the following...

  7. Study of Maximum Swimming Speed Tilapia (Oreochromis Niloticus) for Fisheries Management

    OpenAIRE

    Primeswari, Ridha; ', Nofrizal; Sari, T. Ersti Yulika

    2015-01-01

    The purpose of this study was to determine the swimming speed of the free swimming intank and flume tank, an outdoor durability of tilapia (Oreochromis niloticus), and maximumswimming speed tilapia in flume tank. Therefore, to use experimental methods. Free swimmingspeed was 0,25 BL/sec, maximum swimming speed of fish occurs when the fish are given ashock to swim. Negative correlation between speed and endurance swimming R2 = 0,7295 showsa fish swimming endurance decreases at higher speeds. S...

  8. Effects of disinfecting alginate impressions on the scratch hardness of stone models.

    Science.gov (United States)

    Hiraguchi, Hisako; Nakagawa, Hisami; Wakashima, Mitsuru; Miyanaga, Kohichi; Saigo, Masataka; Nishiyama, Minoru

    2006-03-01

    This study investigated the effects of disinfecting alginate impressions on the scratch depth of resultant stone models. Eleven brands of alginate impression material and two disinfectants, 1% sodium hypochlorite and 2% glutaraldehyde, were used. Impressions were immersed in disinfectant solutions or stored in sealed bags after spraying with disinfectants, and then poured with a type V dental stone. The scratch depth of the stone model obtained from disinfected impression was measured. The storage of alginate impressions after spraying with disinfectants did not increase the scratch depth of resultant stone models. However, the effect of immersion in disinfectants on scratch depth varied with the brand of the alginate impression material.

  9. Patent pools: Intellectual property rights and competition.

    NARCIS (Netherlands)

    Rodriguez, V.F.

    2010-01-01

    Patent pools do not correct all problems associated with patent thickets. In this respect, patent pools might not stop the outsider problem from striking pools. Moreover, patent pools can be expensive to negotiate, can exclude patent holders with smaller numbers of patents or enable a group of major

  10. Mechanical krill models for studying coordinated swimming

    Science.gov (United States)

    Montague, Alice; Lai, Hong Kuan; Samaee, Milad; Santhanakrishnan, Arvind

    2016-11-01

    The global biomass of Homo sapiens is about a third of the biomass of Euphausia superba, commonly known as the Antarctic krill. Krill participate in organized social behavior. Propulsive jets generated by individual krill in a school have been suggested to be important in providing hydrodynamic sensory cues. The importance of body positions and body angles on the wakes generated is challenging to study in free swimming krill. Our solution to study the flow fields of multiple krill was to develop mechanical krill robots. We designed krillbots using mostly 3D printed parts that are actuated by stepper motors. The krillbot limb lengths, angles, inter-limb spacing and pleopod stroke frequency were dynamically scaled using published data on free-swimming krill kinematics. The vertical and horizontal spacing between krillbots, as well as the body angle, are adjustable. In this study, we conducted particle image velocimetry (PIV) measurements with two tethered krillbots in a flow tank with no background flow. One krillbot was placed above and behind the other. Both krillbots were at a zero-degree body angle. Wake-body interactions visualized from PIV data will be presented.

  11. 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.

  12. 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

  13. Modulation of the anticonvulsant effect of swim stress by agmatine.

    Science.gov (United States)

    Bahremand, Taraneh; Payandemehr, Pooya; Riazi, Kiarash; Noorian, Ali Reza; Payandemehr, Borna; Sharifzadeh, Mohammad; Dehpour, Ahmad Reza

    2018-01-01

    Agmatine is an endogenous l-arginine metabolite with neuroprotective effects in the stress-response system. It exerts anticonvulsant effects against several seizure paradigms. Swim stress induces an anticonvulsant effect by activation of endogenous antiseizure mechanisms. In this study, we investigated the interaction of agmatine with the anticonvulsant effect of swim stress in mice on pentylenetetrazole (PTZ)-induced seizure threshold. Then we studied the involvement of nitric oxide (NO) pathway and endogenous opioid system in that interaction. Swim stress induced an anticonvulsant effect on PTZ seizures which was opioid-independent in shorter than 1-min swim durations and opioid-dependent with longer swims, as it was completely reversed by pretreatment with naltrexone (NTX) (10mg/kg), an opioid receptor antagonist. Agmatine significantly enhanced the anticonvulsant effect of opioid-independent shorter swim stress, in which a combination of subthreshold swim stress duration (45s) and subeffective dose of agmatine (1mg/kg) revealed a significantly higher seizure threshold compared with either one. This effect was significantly reversed by NO synthase inhibitor N G -nitro-l-arginine (L-NAME (Nω-Nitro-L-arginine methyl ester), 5mg/kg), suggesting an NO-dependent mechanism, and was unaffected by NTX (10mg/kg), proving little role for endogenous opioids in the interaction. Our data suggest that pretreatment of animals with agmatine acts additively with short swim stress to exert anticonvulsant responses, possibly by mediating NO pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. 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

  15. The Complex Hydrodynamics of Swimming in the Spanish Dancer

    Science.gov (United States)

    Zhou, Zhuoyu; Mittal, Rajat

    2016-11-01

    The lack of a vertebra seems to have freed marine gastropods to explore and exploit a stupendous variety of swimming kinematics. In fact, examination of just a few animals in this group reveal locomotory modes ranging from insect-like flapping, to fish-like undulatory swimming, jet propulsion, and rajiform (manta-like) swimming. There are also a number of marine gastropods that have bizarre swimming gaits with no equivalent among fish or marine mammals. In this latter category is the Spanish Dancer (Hexabranchus sanguineus) a sea slug that swims with a complex combination of body undulations and flapping parapodia. While the neurobiology of these animals has been relatively well-studied, less is known about their propulsive mechanism and swimming energetics. In this study, we focus on the hydrodynamics of two distinct swimmers: the Spanish Dancer, and the sea hare Aplysia; the latter adopts a rajiform-like mode of swimming by passing travelling waves along its parapodia. In the present study an immersed boundary method is employed to examine the vortex structures, hydrodynamic forces and energy costs of the swimming in these animals. NSF Grant No. 1246317.

  16. 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 ...

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

    African Journals Online (AJOL)

    ... study of transaminase activities in liver and kidney. Results lead to conclude that the composite extract of above three plant parts has a therapeutic protective effect on forced swimming-induced oxidative stress in vital organs. Keywords: Brain tissues, metabolic organs, oxidative stress, phytotherapy, swimming, vitamin-E.

  18. 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... BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.734 Navesink River (Swimming River). The Oceanic Bridge, mile 4.5, shall open on signal; except that, from December 1 through...

  19. Peculiarities of a backstroke swimming technique acceleration in elementary education

    Directory of Open Access Journals (Sweden)

    Liliya Sheyko

    2016-02-01

    Full Text Available Purpose: to research the possibility of intensification and improvement of the efficiency of swimming training for adults by use of accelerated learning backstroke swimming techniques. Material & Methods: the study involved a total of 43 people aged 30–40 years. Applied: analysis and generalization of scientific and methodological literature; analysis of the learning process of swimming training for adults; development and approbation of an accelerated backstroke swimming technique on the base of the recreational sports complex LLC «Technocom» (Kharkiv, Author's swimming school of U. Blyzniuk, teacher observation, experiment. Results: a study shows that developing of swimming skills of people tested occurs faster and more effectively if the accelerated procedure is used. Backstroke swimming skill formation time for examinees: check group had 26 to 36 lessons, there were 25 to 32 exercises with and without use of supporting means; the experimental group had 12 to 24 lessons with use of 15 exercises without supporting means. Conclusions: as a result of the experiment, it was found that the use of the proposed accelerated training method allows to intensify backstroke swimming learning process for people aged 30–40, due to training course total duration reduction (2 times and number of exercises used, and also allows to master quicker the main improving distance according to age of the engaged.

  20. 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

  1. Relationship between Muscle Strength and Front Crawl Swimming Velocity

    Directory of Open Access Journals (Sweden)

    Gola Radosław

    2014-08-01

    Full Text Available Purpose. competitive performance in swimming depends on a number of factors including, among others, the development of relevant muscle groups. The aim of the study was to clarify the relationship between muscle strength and swimming velocity and the role of individual muscle groups in front crawl swimming. Methods. sixteen physical education university students participated in the study. The strength values, defined as torque produced during isometric contractions, of eight upper and lower extremity muscle groups were measured. Data were compared with participants' front crawl swim times in the 25m and 50m distances. Results. correlation analysis demonstrated a relationship between muscle strength and swimming velocity. statistically significant relationships were observed between swimming velocity and the torque values of the elbow flexor and shoulder extensor muscles as well as the sum of upper extremity muscle torque values (p ⋋ 0.05. Conclusions. The results indicate the need for a focus on training those muscle groups identified as having a statistically significant relationship with swimming velocity for a given distance, as the sample showed deficiencies in the strength of those muscle groups responsible for generating propulsive force in the front crawl. Additionally, the collected data can serve as a diagnostic tool in evaluating the development of muscle groups critical for swimming performance.

  2. The determination of drag in front crawl swimming

    NARCIS (Netherlands)

    Toussaint, H.M.; Roos, P.E.; Kolmogorov, S.

    2004-01-01

    The measurement of drag while swimming (i.e. active drag) is a controversial issue. Therefore, in a group of six elite swimmers two active drag measurement methods were compared to assess whether both measure the same retarding force during swimming. In method 1 push-off forces are measured directly

  3. Children's Activity Levels and Lesson Context during Summer Swim Instruction

    Science.gov (United States)

    Schwamberger, Benjamin; Wahl-Alexander, Zachary

    2016-01-01

    Summer swim programs provide a unique opportunity to engage children in PA as well as an important lifesaving skill. Offering summer swim programs is critical, especially for minority populations who tend to have higher rates of drowning, specifically in youth populations. The purpose of this study was to determine the lesson context and…

  4. Physiological responses to swimming fatigue of juvenile white-leg ...

    African Journals Online (AJOL)

    Swimming performance is one of the crucial factors determining the lifestyle and survival of Penaeid shrimps. This study examined under controlled laboratory conditions, the physiological responses to swimming fatigue of juvenile white-leg shrimp Litopenaeus vannamei (8.85 ± 0.05 cm TL) exposed to different current ...

  5. 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

  6. 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

  7. Wild-type Zebrafish subjected to swim-training

    NARCIS (Netherlands)

    Fiaz, Ansa

    2014-01-01

    Genome-wide microarray analysis of the effects of swim-training on zebrafish larval development. Zebrafish were subjected to swim-training from 5 days post fertilization (dpf) until 10 dpf. Subsequently, we performed a genome-wide microarray analysis of trained and control fish at 10 dpf. The goal

  8. 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.

  9. Microbiological methods for testing disinfectant efficiency on Pseudomonas biofilm.

    Science.gov (United States)

    Wirtanen; Salo; Helander; Mattila-Sandholm

    2001-01-15

    Biofilms of the Gram-negative bacteria Pseudomonas aeruginosa and Pseudomonas fragi were grown on stainless steel surfaces (AISI 304, 2B) for 4 days in slime broth. These biofilms were treated with four commercial disinfectants. The disinfectants were alcohol-based, tenside-based, peroxide-based and chlorine-based products, covering most disinfectant types used in the food industry. The effects of the disinfectants on the bacterial cells were first investigated in suspension using the permeabilisation test, which is based on fluorescence assessment of hydrophobic 1-N-phenyl-naphtylamine (NPN). The surfaces covered with disinfectant-treated biofilms were investigated using conventional cultivation, impedimetry and epifluorescence microscopy in combination with image analysis of preparations stained with the DNA-stain acridine orange and with the metabolic indicator system CTC-DAPI. The results showed that the tenside-based and peroxide-based disinfectants permeabilised the cells in suspension. The overall biofilm results showed that of the agents tested, the peroxide-based and chlorine-based disinfectants acted most effectively on cells in biofilms.

  10. ASSESSMENT OF ACTION OF DISINFECTANTS AGAINST LISTERIA MONOCYTOGENES BIOFILMS

    Directory of Open Access Journals (Sweden)

    T. K. CABEÇA

    2008-12-01

    Full Text Available

    The purpose of this study was to assess the action of various disinfectants used in food industry against biofilm cells of Listeria monocytogenes formed on stainless steel surfaces during 24, 72 and 120 hours. Numbers of viable biofilm cells decreased after treatment with all the tested disinfectants (iodine, biguanide, quaternary ammonium compounds, peracetic acid and sodium hypochlorite. Sodium hypochlorite was the most effective disinfectant against the biofilm cells, while biguanide and iodine were the least. Scanning electron microscopy observations demonstrated attached cells on stainless steel surfaces after treatment with all the disinfectants. These observations showed that microorganisms were not completely removed from stainless steel surfaces after treatment with the disinfectants, however, the attachment did not means the viability of remaining cells. The biofilm age in hours (24, 72 and 120 had no apparent influence on resistance of microbiological cells to the disinfectants under study. In conclusion biofilm cells of L. monocytogenes can withstand disinfectants action.

  11. Italian National Survey of Digestive Endoscopy Disinfection Procedures.

    Science.gov (United States)

    Orsi, G B; Filocamo, A; Di Stefano, L; Tittobello, A

    1997-10-01

    Inadequate disinfection of endoscopes and associated instrumentation can result in transmission of bacterial infections to patients. The aim of this study was to investigate the disinfection procedures carried out in the Italian centers of digestive endoscopy. An anonymous postal questionnaire on the methods of cleaning and disinfecting endoscopy equipment in Italy was sent to 781 digestive endoscopy centers; 386 units (49.4 %) replied. Automatic washers were available in 47.6% of units. Nearly all the respondets (99.2%) cleaned the instruments before disinfection, using detergent, germicidal or enzymatic cleaner, but only 69.7% carried out brushing. Most centers (89.2 %) used a glutaraldehyde-based disinfectant (51 % used 2 % glutaraldehyde; 26.9% used 0.4% glutaraldehyde with 1.41% phenol and 0.26% sodium phenate; 5.9% used either; 5.4% did not specify glutaraldehyde formulation). The contact time of the disinfectant was or = 30 minutes (16.6%). The use-life of the disinfectant was > or = 14 days in 27.3 % of the centers with automatic washers and 30.8% in all centers. Only 25.4% of the centers carried out some form of sterilization for biopsy forceps. The majority (83.4 %) modified their disinfection procedures in the case of infectious disease patients. Quality control tests on the efficacy of the endoscopy disinfection procedures were carried out in 44.6 % of units. Only 43 % of the centers were based in hospitals with an infection control (surveillance) program. The data collected in the study showed that, in general, there is compliance with the Società Italiana di Endoscopia Digestiva (SIED) and Società Italiana di Gastroenterologia (SIGE) guidelines, although with some important exceptions.

  12. [Disinfection of medical and surgical equipment: efficacy of chemical disinfectants and water and soap].

    Science.gov (United States)

    Silva e Souza, A C; Pereira, M S; Rodrigues, M A

    1998-07-01

    In this experimental study we compared the previous descontamination efficacy of the medical surgical materials by the use of chemical disinfectants and the mechanical cleaning with water and soap, as well as verified the organic material interference in these procedures. To carry out this study, we used surgical pincers under contamination with: Staphylococcus aureus ATCC-6538, Salmonella cholerae suis ATCC-10708, and Pseudomonas aeruginosa ATCC-15442 in presence and absence of organic matter (fetal bovine serum). The following treatments: glutaraldehyde 2%, sodium hypochlorite 1%, hydrogen peroxide 6%, alcohol 70% and the mechanical cleaning with water and soap were compared with eight repetitions in a total of 480 observations. In the described conditions, the disinfectants had a good efficacy in the previous descontamination of the medical surgical materials and a less inactivation by the organic material. The mechanical cleaning with water and soap showed a reduction of the microrganism to safe levels, considered adequate for previous descontamination.

  13. EP BICYCLE POOL - VIGNETTES 2002

    CERN Multimedia

    EP-SMI Help Desk

    2002-01-01

    The vignettes (insurance certificates) for 2002 become obligatory from 1 June. If you have a bicycle from the EP Pool, please bring it to the EP-SMI Help Desk (Building 124) on any working day up to 31 May between 8h.30 - 12h.00 or 13h.30 - 17h.30. EP-SMI Help Desk

  14. 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

  15. CONCERNS OF CONTEMPORARY DISINFECTION: CHLORINE OR STABILIZED LIQUID SOLUTION OF CHLORINE DIOXIDE

    OpenAIRE

    Abdulah Gagić; Selma Selimović; Suad Jukić; Ajla Ališah; Aida Kustura

    2014-01-01

    It is common that experts use routine procedures for disinfection. Every part of the disinfection procedure is routinely done: preparation of the disinfection media, selection of the type of disinfection, protective measures, effect control and environmental issues. This article offers a new insight into the use of stabilized liquid chlorine dioxide as a qualitative alternative disinfectant for wider application by comparing it to the most frequently used chlorine and its compounds. When used...

  16. Efficient pooling designs for library screening

    OpenAIRE

    Bruno, William J.; Knill, Emanuel; Balding, David J.; Bruce, D. C.; Doggett, N. A.; Sawhill, W. W.; Stallings, R. L.; Whittaker, Craig C.; Torney, David C.

    1994-01-01

    We describe efficient methods for screening clone libraries, based on pooling schemes which we call ``random $k$-sets designs''. In these designs, the pools in which any clone occurs are equally likely to be any possible selection of $k$ from the $v$ pools. The values of $k$ and $v$ can be chosen to optimize desirable properties. Random $k$-sets designs have substantial advantages over alternative pooling schemes: they are efficient, flexible, easy to specify, require fewer pools, and have er...

  17. Drinking Water Supply without Use of a Disinfectant

    Science.gov (United States)

    Rajnochova, Marketa; Tuhovcak, Ladislav; Rucka, Jan

    2018-02-01

    The paper focuses on the issue of drinking water supply without use of any disinfectants. Before the public water supply network operator begins to consider switching to operation without use of chemical disinfection, initial assessment should be made, whether or not the water supply system in question is suitable for this type of operation. The assessment is performed by applying the decision algorithm. The initial assessment is followed by another decision algorithm which serves for managing and controlling the process of switching to drinking water supply without use of a disinfectant. The paper also summarizes previous experience and knowledge of this way operated public water supply systems in the Czech Republic.

  18. Combined inhalation of beta2 -agonists improves swim ergometer sprint performance but not high-intensity swim performance

    DEFF Research Database (Denmark)

    Kalsen, Anders; Hostrup, Morten; Bangsbo, Jens

    2014-01-01

    ), in permitted doses within the World Anti-Doping Agency 2013 prohibited list, in elite swimmers with (AHR, n = 13) or without (non-AHR, n = 17) AHR. Maximal voluntary isometric contraction of m. quadriceps (MVC), sprint performance on a swim ergometer and performance in an exhaustive swim test at 110% of VO2max...

  19. Antimicrobial-Coated Granules for Disinfecting Water

    Science.gov (United States)

    Akse, James R.; Holtsnider, John T.; Kliestik, Helen

    2011-01-01

    Methods of preparing antimicrobialcoated granules for disinfecting flowing potable water have been developed. Like the methods reported in the immediately preceding article, these methods involve chemical preparation of substrate surfaces (in this case, the surfaces of granules) to enable attachment of antimicrobial molecules to the surfaces via covalent bonds. A variety of granular materials have been coated with a variety of antimicrobial agents that include antibiotics, bacteriocins, enzymes, bactericides, and fungicides. When employed in packed beds in flowing water, these antimicrobial-coated granules have been proven effective against gram-positive bacteria, gram-negative bacteria, fungi, and viruses. Composite beds, consisting of multiple layers containing different granular antimicrobial media, have proven particularly effective against a broad spectrum of microorganisms. These media have also proven effective in enhancing or potentiating the biocidal effects of in-line iodinated resins and of very low levels of dissolved elemental iodine.

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

    Science.gov (United States)

    2016-08-01

    data are needed to manage invasive bigheaded or “ Asian ” carps (Figure 1). However, such data are limited within the scientific literature . The large...ERDC/TN ANSRP-16-1 August 2016 Approved for public release; distribution is unlimited. Swimming Performance of Adult Asian Carp: Field...these invasive species in North American waterways. Such data can be used to assess rates of movement (Konagaya and Cai 1987; 1989), the likelihood of