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Sample records for multi-purpose disinfecting solution

  1. A multicenter investigation of OPTI-FREE® RepleniSH® multi-purpose disinfecting solution impact on soft contact lens patient comfort

    PubMed Central

    Corbin, Glenn S; Bennett, Linda; Espejo, Louis; Carducci, Suzanne; Sacco, Andrew; Hannigan, Robert; Schatz, Stuart

    2010-01-01

    Objective: Demonstrate that successful soft contact lens wearers using competitive multipurpose solutions report improvement in comfort with OPTI-FREE® RepleniSH® Multi-Purpose Disinfecting Solution (MPDS). Methods: This 30-day, multicentered, open-label study enrolled 109 eligible soft contact lens wearers using COMPLETE® Multi-Purpose Solution (MPS) Easy Rub® or ReNu MultiPlus® MPS. The test solution (OPTI-FREE® RepleniSH® MPDS) was dispensed for use in place of habitual care solutions. Subjects assessed their experience with their habitual solution (baseline) and the test solution (Day 30) using Likert-style questions. Contact lens acuity and biomicroscopy findings were recorded at each visit. Results: The test solution was associated with a statistically significant improvement in instillation comfort (P = 0.02), end of day comfort (P < 0.0001), clear vision (P < 0.0001) and overall satisfaction (P < 0.001). Subjects reported the test solution enhanced their overall lens-wearing experience more effectively than their previous solution (P < 0.0001) and that they would continue test solution use after the study (P < 0.0001). Conclusions: The test solution was effective at improving comfort and overall contact lens experience compared to COMPLETE® MPS Easy Rub® or ReNu MultiPlus® MPS in successful contact lens wearers. These results indicate that changing contact lens care solutions, even in successful lens wearers, may improve comfort and overall lens-wearing experience. PMID:20169049

  2. Multi-Purpose Tests: A Solution to Test Proliferation.

    ERIC Educational Resources Information Center

    Holmes, Susan E.

    This research, conducted for California State Department of Education, is one component of a feasibility study focusing on ways to make the testing process more efficient by application of multi-purpose tests (MPT). MPT are designed, administered and scored to serve more than one purpose and to consolidate and unify testing programs as a partial…

  3. Comparative evaluation of multi-purpose solutions in the stabilization of tear lysozyme.

    PubMed

    Barniak, Vicki L; Burke, Susan E; Venkatesh, Srini

    2010-12-01

    The range and extent of tear proteins removed by various multi-purpose solutions has been investigated, but there is little information in the literature about their ability to prevent denaturation of tear proteins, particularly lysozyme. The purpose of this study was to determine the ability of Bausch+Lomb Biotrue™ multi-purpose solution and other care solutions to affect denaturation of lysozyme using a lysozyme activity assay. The test solutions used were: Biotrue multi-purpose solution, Bausch+Lomb renu(®) fresh™, formerly ReNu MultiPlus(®), Alcon OPTI-FREE RepleniSH, Alcon OPTI-FREE EXPRESS, CIBA VISION AQuify, and AMO COMPLETE Multi-Purpose Solution Easy Rub Formula. A phosphate-buffered saline (PBS) solution served as a control. The test and control solutions containing lysozyme were exposed to sodium dodecyl sulfate (SDS), a known denaturant of the enzyme. The assay was based on digestion of the cell wall of Micrococcus luteus in a suspension, a substrate sensitive to active lysozyme. Enzymatic activity against M. luteus was used to assess activity of lysozyme. The decrease in the turbidity of the cell wall suspension, a measure of relative enzyme activity, was determined by following the decrease in absorbance (at 450nm) over time using a spectrophotometer. Statistically significant greater stabilization of lysozyme was observed with Biotrue multi-purpose solution and renu fresh than with OPTI-FREE RepleniSH, OPTI-FREE EXPRESS, AQuify, COMPLETE Multi-Purpose Solution Easy Rub Formula, and a PBS control. The lysozyme activity assay revealed that Biotrue multi-purpose solution and renu fresh have the ability to stabilize lysozyme under conditions that typically denature the protein.

  4. Nonclinical safety evaluation of boric acid and a novel borate-buffered contact lens multi-purpose solution, Biotrue™ multi-purpose solution.

    PubMed

    Lehmann, David M; Cavet, Megan E; Richardson, Mary E

    2010-12-01

    Multipurpose solutions (MPS) often contain low concentrations of boric acid as a buffering agent. Limited published literature has suggested that boric acid and borate-buffered MPS may alter the corneal epithelium; an effect attributed to cytotoxicity induced by boric acid. However, this claim has not been substantiated. We investigated the effect of treating cells with relevant concentrations of boric acid using two cytotoxicity assays, and also assessed the impact of boric acid on corneal epithelial barrier function by measuring TEER and immunostaining for tight junction protein ZO-1 in human corneal epithelial cells. Boric acid was also assessed in an in vivo ocular model when administered for 28 days. Additionally, we evaluated Biotrue multi-purpose solution, a novel borate-buffered MPS, alone and with contact lenses for ocular compatibility in vitro and in vivo. Boric acid passed both cytotoxicity assays and did not alter ZO-1 distribution or corneal TEER. Furthermore, boric acid was well-tolerated on-eye following repeated administration in a rabbit model. Finally, Biotrue multi-purpose solution demonstrated good ocular biocompatibility both in vitro and in vivo. This MPS was not cytotoxic and was compatible with the eye when administered alone and when evaluated with contact lenses. We demonstrate that boric acid and a borate-buffered MPS is compatible with the ocular environment. Our findings provide evidence that ocular effects reported for some borate-buffered MPS may be incorrectly attributed to boric acid and are more likely a function of the unique combination of ingredients in the MPS formulation tested. Copyright © 2010 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  5. The role of multi-purpose solutions in prevention and removal of lipid depositions on contact lenses.

    PubMed

    Tam, Ngai Keung; Pitt, William G; Perez, Krystian X; Handly, Erika; Glenn, Andrew A; Hickey, John W; Larsen, Brian G

    2014-12-01

    The sorption and desorption of radiolabeled dipalmitoylphosphatidylcholine (DPPC) and cholesterol (CH) were measured on 5 types of commercial contact lenses. The lenses were soaked in vitro in an artificial tear fluid for 16h. The effects of borate buffered saline and two commercial multi-purpose lens-care solutions (MPSs) on reducing the lipid (DPPC and CH) sorption and increasing the lipid removal were examined. The results showed that silicone hydrogel (SiHy) lenses accumulated the most lipids, sorbing over an order of magnitude more than polymacon, a conventional hydrogel lens. Pre-soaking the SiHy lenses for 16h in MPSs reduced the DPPC sorption by up to 13% and the CH sorption by up to 11%, compared to controls that were not pre-soaked. However neither these reductions nor those on polymacon were statistically significant (p>0.05). In sorption experiments without presoaking, subsequent exposure to the MPSs removed some DPPC from the lenses (0-3.1% for SiHy lenses and 14-55% for polymacon), but CH removal was 0.0-0.8% for SiHy lenses and 0.6-28% for polymacon lenses. Some of these removals were statistically significant (p<0.05).

  6. Antifungal efficacy of soft contact lens disinfecting solutions against Fusarium solani and Candida albicans.

    PubMed

    Mohammadinia, Mohadeseh; Amiri, Mohammad Aghazadeh; Delavari, Fatemeh; Yousefzadeh, Bahman; Maymeh, Maryam Heydarpour

    2012-03-01

    The aim was to evaluate the disinfection properties of six multi-purpose contact lens disinfection solutions (MPDS) available in Iran against Fusarium solani and Candida albicans, based on the International Organization for Standardization (ISO) 14729 guidelines. Three lots each of six multi-purpose solutions, namely, Renu MultiPlus, Solo Care Aqua, All-Clean soft, Contact All In One Advanced, Hippia, Ginza Multi-Purpose Solution and 0.9% normal saline solution were inoculated with standard strains of Fusarium solani (ATCC 36031) and Candida albicans (ATCC 10231). Surviving fungi were determined by counting colony-forming units on recovery plates at specified times. The mean log reduction in fungal numbers at the manufacturer's minimum recommended disinfection time was determined and compared with the criteria for stand-alone disinfection products for each MPDS against each fungal strain. Renu MultiPlus, Contact All In One Advanced and All-Clean Soft were effective in achieving the mean 1.0 log reduction in fungal numbers, based on ISO 14729 stand-alone primary acceptance criteria. Solo Care Aqua failed to achieve the ISO 14729 stand-alone primary acceptance criteria for Candida albicans. The other solutions were not effective against test microorganisms after the specified times. There were differences in the rates of disinfection efficacy. Generally, Renu MultiPlus, Contact All In One Advanced and All-Clean Soft exceeded the primary acceptance criteria of the ISO 14729 guidelines for stand-alone contact lens solutions. © 2012 Government of Iran. Clinical and Experimental Optometry © 2012 Optometrists Association Australia.

  7. Evaluating the potential of multi-purpose nature based solutions in peri-urban landscapes - a preliminary assessment

    NASA Astrophysics Data System (ADS)

    Geris, Josie; Wilkinson, Mark; Stutter, Marc; Guenther, Daniel; Soulsby, Chris

    2016-04-01

    Many communities across the world face the increasing challenge of balancing water quantity and quality protection and improvement with accommodating new growth and urban development. Urbanisation is typically associated with detrimental changes in water quality, sediment delivery, and effects on water storage and flow pathways (e.g. increases in flooding). Current mitigation solutions are typically based on isolated design strategies used at specific small scale sites and for storm water only. More holistic catchment scale approaches are urgently required to effectively manage the amount of water flows and protect the raw water quality in peri-urban landscapes. This project aims to provide a better understanding of the connectivity between natural and managed flow pathways, storage, and biogeochemical processes in the peri-urban landscape to eventually aid a more integrated water quantity and quality control design. For an actively urbanising catchment in NE Scotland we seek to understand the spatio-temporal character of the natural flow pathways and associated water quality, and how these may be used to support the design of nature based solutions during urbanisation. We present preliminary findings from a dense and multiscale monitoring network that includes hydrometric, tracer (stable water isotopes) and water quality (turbidity (sediment), nitrate, phosphate) data during a range of contrasting hydroclimatological conditions and at different stages of the development of urban infrastructure. These demonstrate a highly variable nature, both temporally and spatially, with water quality dynamics out of sync with storm responses and depending on management practices. This highlights potential difficulties for managing water quantity and quality simultaneously at the catchment scale, and suggests that a treatment train approach may be required. Well-designed nature based solutions that tackle both water quantity and quality issues will require adaptability and a

  8. Belford proactive flood solutions: scientific evidence to influence local and national policy by multi-purpose runoff management

    NASA Astrophysics Data System (ADS)

    Wilkinson, M.; Quinn, P. F.; Jonczyk, J.

    2010-12-01

    The increased risk from flooding continues to be of concern to governments all around the world and flood protection is becoming more of a challenge. In the UK, climate change projections indicate more extremes within the weather systems. In addition, there is an increased demand for using land in urban areas beside channels. These developments both put pressure on our flood defences and there is a need for new solutions to managing flood risk. There is currently support within the England and Wales Environment Agency for sustainable flood management solutions such as storage ponds, wetlands, beaver dams and willow riparian features (referred to here as Runoff Attenuation Features, or RAFs). However the effectiveness of RAFs are not known at the catchment scale since they have only really been trailed at the plot scale. These types of mitigation measure can offer benefits to water quality and create ecological habitats. The village of Belford, situated in the Belford Burn catchment (6km2), northern England, has suffered from numerous flood events. In addition, the catchment suffers from water quality issues within the channel and high sediment loads are having an impact on the ecology of the nearby estuary. There was a desire by the Local Environment Agency Flood Levy team to deliver an alternative catchment-based solution to the problem. With funding from the Northumbria Regional Flood Defence Committee, the Environment Agency North East Local Levy team and Newcastle University have created a partnership to address the flood problem trailing soft engineered RAF’s at the catchment scale. The partnership project, “Belford proactive flood solutions” is testing novel techniques in reducing flood risk in small sub-catchments for the Environment Agency. The project provides the information needed to understand whether the multi-functional mitigation measures are working at the sub-catchment scale. Data suggest that the mitigation measures present have delayed the

  9. Antiviral efficacy of disinfectant solution MRI-1.

    PubMed

    Skinner, G R; Billstrom, M; Randall, S; Buchan, A; Davies, J; Ahmad, A

    1998-01-01

    Disinfectant MRI-1 was prepared by dissolution of non-ionic and ionic detergent in ethanol. The disinfectant inactivated extracellular and intracellular enveloped and non-enveloped viruses including herpes viruses, influenza A and human immunodeficiency disease virus in suspension or on surfaces by pre-exposure or post-exposure to the disinfectant; in addition, cells were disabled as potential hosts for viral infection using concentrations of MRI-1 which were 50-fold less than the operative concentration for disinfection. There was no evidence of in vitro mutagenicity using Salmonella typhimurium or sensitization or other adverse effect in a guinea pig model or in human subjects.

  10. Use of buffered hypochlorite solution for disinfecting fibrescopes.

    PubMed

    Coates, D; Death, J E

    1982-03-01

    The possible use of sodium hypochlorite solution buffered to pH 7.6 and containing 100 ppm available chlorine (avCl) for disinfecting fibrescopes was investigated. A flexible fibrescope experimentally contaminated with Pseudomonas putida, Mycobacterium fortuitum, or Bacillus subtilis spores was effectively disinfected within 10 m in repeatedly and without any observable adverse effect on the instrument. The corrosive nature of buffered hypochlorite was investigated by immersing various fibrescope components and metal wires in solutions of different strength for long periods and examining them for damage. Stainless steel, platinum, glass, Teflon, polythene and epoxy resin were apparently unaffected whereas polyurethane, rubber and other metals tested were damaged to different extents. Buffered hypochlorite solutions may have many applications pertaining to the disinfection of items which are either thermolabile or require rapid effective disinfection.

  11. 9 CFR 96.14 - Uncertified casings; disinfection with saturated brine solution.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Uncertified casings; disinfection with... § 96.14 Uncertified casings; disinfection with saturated brine solution. Foreign animal casings offered for importation into the United States upon disinfection, may either be disinfected with hydrochloric...

  12. Corrosion of dental burs in sterilizing and disinfecting solutions.

    PubMed

    Bapna, M S; Mueller, H J

    1988-04-01

    Potentiodynamic anodic polarization, SEM, and energy dispersive microanalysis techniques were used to determine electrochemical aggressiveness of disinfecting and sterilizing solutions on carbide and stainless steel burs. The importance of galvanic cell formation in carbide burs caused by mixed metal coupling was examined. The following conclusions were reached. 1. Anodic polarization methods are an effective means for discriminating among the relative corrosiveness of sterilizing and disinfecting agents on dental instruments, particularly dental burs. 2. The relative degree of corrosiveness on stainless steel burs shows Omni II and Omnicide solutions the best, Sterall and Sporicidin solutions the poorest, and Glutarex solution intermediate. Omnicide and Glutarex solutions show the least degree of corrosiveness on the carbide burs. 3. SEM analysis of ground, polished, and treated surfaces shows corrosion deposition over the soldered joint of the carbide burs. The stainless steel shank is a cathodic component of a three-way galvanic cell, whereas the silver soldered joint is an anodic component.

  13. Hydrophobic Polycationic Coatings Disinfect Poliovirus and Rotavirus Solutions

    PubMed Central

    Larson, Alyssa M.; Hsu, Bryan B.; Rautaray, Debabrata; Haldar, Jayanta; Chen, Jianzhu

    2011-01-01

    Coating surfaces with N-alkylated polyethylenimines (PEIs), namely branched N,N-hexyl,methyl-PEI via covalent attachment to glass or linear N,N-dodecyl,methyl-PEI by physical deposition (“painting”) onto polyethylene, enables the resultant materials to quickly and efficiently disinfect aqueous solutions of (non-enveloped) poliovirus and rotavirus. PMID:20967804

  14. Hydrophobic polycationic coatings disinfect poliovirus and rotavirus solutions.

    PubMed

    Larson, Alyssa M; Hsu, Bryan B; Rautaray, Debabrata; Haldar, Jayanta; Chen, Jianzhu; Klibanov, Alexander M

    2011-03-01

    Coating surfaces with N-alkylated polyethylenimines (PEIs), namely branched N,N-hexyl,methyl-PEI via covalent attachment to glass or linear N,N-dodecyl,methyl-PEI by physical deposition ("painting") onto polyethylene, enables the resultant materials to quickly and efficiently disinfect aqueous solutions of (non-enveloped) poliovirus and rotavirus.

  15. Efficacy of commercial soft contact lens disinfectant solutions against Acanthamoeba.

    PubMed

    Kobayashi, Takeshi; Gibbon, Lindsay; Mito, Tsuyoshi; Shiraishi, Atsushi; Uno, Toshihiko; Ohashi, Yuichi

    2011-09-01

    To investigate the relative efficacy of Japanese commercial soft contact lens disinfectant solutions against Acanthamoeba trophozoites and cysts. Eight types of multipurpose solution (MPS), two types of hydrogen peroxide solution, and one povidone-iodine solution were evaluated to determine their effect against Acanthamoeba trophozoites and cysts (ATCC 50514). Acanthamoeba cysts were cultured in encystment medium for either 1 or 2 weeks (1 and 2-week-old cysts). The trophozoites and cysts were treated with each disinfectant solution for 0, 2, 4, 8, or 24 h. After performing four tenfold serial dilutions of each test solution, dilutions were cultured for 10 days. The number of surviving organisms was calculated using the trimmed Spearman-Karber method. Among the MPS tested, only four were effective against trophozoites after treatment for 4 h, and none was effective against 2-week-old cysts. Hydrogen peroxide had a significant effect on trophozoites and 1-week-old cysts, but not on 2-week-old cysts. In contrast, povidone-iodine caused a 2.6 log reduction in 2-week-old cysts. MPS were found to have limited efficacy against trophozoites and no efficacy against 2-week-old cysts. Only povidone-iodine had any efficacy against 2-week-old cysts.

  16. [Antimicrobial and sporicidal efficacy of various disinfectant solutions].

    PubMed

    Gismondo, M R; Drago, L; Lombardi, A; Fassina, M C; Mombelli, B

    1995-01-01

    The often indiscriminate use of antimicrobial agents has led to increased bacterial resistance over the past years. This phenomenon is above all evident in nosocomial environments but also at a community level. It is therefore important that, in addition to the rational use of antibiotics, an accurate prophylaxis is performed which includes the correct use of disinfectants. This study examines the antimicrobial activity of various commercially available disinfectant solutions consisting of one or more active ingredients. An analysis of the results reveals that products consisting of an association of individual components (quaternary ammonium chloride with o-phenylphenol and/or isopropyl alcohol; chlorhexidine with benzalkonium chloride or with diazolidinylurea and isopropanol) demonstrate a greater efficacy in terms of microbicidal concentration and contact times.

  17. Effects of contact lens solution disinfectants against filamentous fungi.

    PubMed

    Xu, Yan; He, Yi; Zhou, Lutan; Gao, Chuanwen; Sun, Shengtao; Wang, Xiaochong; Pang, Guangren

    2014-12-01

    To assess and compare the antifungal activity of polyhexamethylene biguanide (PHMB), thimerosal, cetylpyridinium chloride, and chlorhexidine, which are disinfectants used in multipurpose disinfectant solutions (MPDSs) against ocular pathogenic Fusarium solani and Aspergillus flavus isolates in vitro. The in vitro activity of PHMB, thimerosal, cetylpyridinium chloride, and chlorhexidine was assessed against 40 isolates of ocular pathogenic fungi that included 24 F. solani and 16 A. flavus isolates. The strains were tested by broth dilution antifungal susceptibility testing of filamentous fungi approved by the CLSI (Clinical and Laboratory Standards Institute) M38-A document. MIC90 (minimum inhibitory concentration for 90% of the organisms) values of PHMB were 4 and 16 μg/mL for F. solani and A. flavus, respectively. MIC90 values of thimerosal were 0.0313 and 0.0625 μg/mL for F. solani and A. flavus, respectively. MIC90 values of cetylpyridinium chloride were 2 and 2 μg/mL for F. solani and A. flavus, respectively. MIC90 values of chlorhexidine were 32 and 32 μg/mL for F. solani and A. flavus, respectively. As a disinfectant used in MPDSs, thimerosal showed the highest levels of antimicrobial activity against ocular pathogenic F. solani and A. flavus isolates. The concentrations of PHMB (0.0001%), cetylpyridinium chloride (0.00014%), and chlorhexidine (0.003%) in MPDSs are sublethal levels for ocular pathogenic F. solani and A. flavus isolates. Although multiple ingredients within MPDSs play a role in antimicrobial efficacy, antimicrobial activity may be significantly influenced by the disinfectants used in the solution formulations.

  18. Effectiveness of two disinfectant solutions and microwave irradiation in disinfecting complete dentures contaminated with methicillin-resistant Staphylococcus aureus.

    PubMed

    Altieri, Karen Tereza; Sanitá, Paula Volpato; Machado, Ana Lucia; Giampaolo, Eunice Teresinha; Pavarina, Ana Cláudia; Vergani, Carlos Eduardo

    2012-03-01

    Methicillin-resistant Staphylococcus aureus (MRSA) biofilm on dentures can be aspirated, thus causing infections such as aspiration pneumonia. The authors evaluated the efficacy of two disinfectant solutions and microwave irradiation in disinfecting complete dentures contaminated with MRSA. The authors contaminated 36 simulated complete dentures with MRSA and divided them into four equal groups: a positive control group consisting of dentures that were not disinfected; a group that soaked in 1 percent sodium hypochlorite for 10 minutes; a group that soaked in 2 percent chlorhexidine gluconate for 10 minutes; and a group that underwent microwave irradiation at 650 watts for three minutes. The authors quantified colony counts and evaluated the long-term effectiveness of disinfection. All dentures from the control group showed substantial microbial growth on the plates (6.24 log(10) colony-forming units per milliliter). The authors observed no evidence of microbial growth on plates of any disinfected dentures. After seven days' incubation, the authors observed broth turbidity in all beakers containing the dentures disinfected with 1 percent sodium hypochlorite. Soaking in chlorhexidine gluconate solution and microwave irradiation resulted in complete disinfection of all dentures contaminated with MRSA in both the short and the long term. Soaking in sodium hypochlorite solution was effective only as a short-term disinfectant. Microwave irradiation and 2 percent chlorhexidine gluconate may have a disinfective application in dental offices and institutions in which denture wearers are treated, thus improving the longevity and quality of life of patients and reducing the burden of disease caused by MRSA.

  19. Multi-purpose canister project

    SciTech Connect

    Williams, J.R.; Clark, J.R.

    1995-12-01

    The U.S. Department of Energy`s (DOE) Office of Civilian Radioactive Waste Management (OCRWM) has investigated various container systems for handling, transporting, storing, and disposing of spent nuclear fuel (SNF) assemblies in its Civilian Radioactive Waste Management System (CRWMS). The primary goal of DOE`s investigations was to select a container technology that could integrate and standardize the handling of the vast majority of commercial SNF at a reasonable cost, while providing flexibility and ensuring the safety of the public and protecting the environment. Several alternative cask and canister concepts were evaluated for SNF assembly packaging to determine the most suitable concept. Of these alternative, the multi-purpose canister (MPC)-based subsystem, as depicted in Figure 1, was determined to be the most suitable. Based on the results of these evaluations, the decision was made to proceed with design and certification of the MPC subsystem. A decision whether to fabricate and deploy MPCs will be made after further studies and the preparation of an environmental impact statement. This presentation summarizes the status of the MPC Project and related activities that have occurred since the 1994 IHLWM.

  20. Some effects of disinfecting solutions on the properties of alginate impression material and dental stone.

    PubMed

    Boden, J; Likeman, P; Clark, R

    2001-01-01

    The study investigated the effect of two disinfecting solutions on one brand of alginate impression material and dental stone. Control impressions were immersed in water for equivalent periods and the effect of storage of impressions after disinfection or control immersion in water was also investigated. There were no significant dimensional changes in impressions poured after one hour. All impressions stored for 16 hours before pouring showed significant dimensional changes. Mixing dental stone with one disinfectant caused a significant softening of the cast. It is strongly recommended that all impressions are thoroughly rinsed with water after disinfection to prevent incorporation of disinfectant in the cast.

  1. Disinfection.

    ERIC Educational Resources Information Center

    Gould, J. P.; Haas, C. N.

    1978-01-01

    Presents a literature review of wastewater disinfection for 1978. This review covers areas such as: (1) mechanisms of inactivation of negative microorganisms by chlorine and ozone; and (2) the effects of various treatment on over-all water quality. A list of 61 references is also presented. (HM)

  2. Disinfection.

    ERIC Educational Resources Information Center

    Gould, J. P.; Haas, C. N.

    1978-01-01

    Presents a literature review of wastewater disinfection for 1978. This review covers areas such as: (1) mechanisms of inactivation of negative microorganisms by chlorine and ozone; and (2) the effects of various treatment on over-all water quality. A list of 61 references is also presented. (HM)

  3. DISINFECTION

    EPA Science Inventory

    The primary goal of the disinfection process in drinking water treatment is the inactivation of microbial pathogens. These pathogens comprise a diverse group of organisms which serve as the etiological agents of waterborne disease. Included in this group are bacterial, viral and ...

  4. [Aqueous iodine solutions as disinfectants: composition, stability, comparison with chlorine and bromine solution (author's transl)].

    PubMed

    Gottardi, W

    1978-09-01

    The equilibrium concentrations of aqueous iodine solutions in dependence of the total concentration and the pH-value have been calculated with and without regard of the iodate formation. The values obtained by the latter methode enabled by application of the known rate law to calculate the initial rate of the iodate formation and to draw from this conclusions concerning the stability of iodine solutions. On the grounds of these calculations to aqueous iodine solutions in the concentration and pH-range which is relevant for disinfection (greater than 10(-5) M/l, pH 6--9) one can attribute a stability sufficient for the use in practice and - unlike chlorine and bromine solutions - a content of bactericidal "free halogene" which is higher and independent of the pH-value. The disinfecting action of the iodine cation (H2O+J) which is supposed to be very powerful can be neglected because of its low concentration (10(-3)--10(-6%) of the total concentration). Hypoiodic acid which has already been converted into iodate by disproportionation is as good as lost for the disinfection because of the extremely slow reverse reaction.

  5. Disinfection of Preexisting Contamination of BACILLUS CEREUS on Stainless Steel when Using Glycoconjugate Solution

    NASA Astrophysics Data System (ADS)

    Pavan, Casey; Tarasenko, Olga

    2011-06-01

    Stainless steel is ubiquitous in our modern world, however it can become contaminated. This can endanger our health. The aim of our study is to disinfect stainless steel using Bacillus cereus as a model organism. Bacillus cereus is a microbe that is ubiquitous in nature, specifically soil. B. cereus is known to cause illness in humans. To prevent this, we propose to use a glycoconjugate solution (GS) for disinfection of stainless steel after it is contamination by B. cereus spores. In this study, two GS (9, 10) were tested for disinfection effectiveness on B. cereus spores on the surface of stainless steel foil (AISI-Series 200/300/400, THERMA-FOIL, Dayville, CT 0241). The disinfection rate of each GS was assessed by exposing the steel surface to B. cereus spores first and allowing them to settle for 24 hours. GS was used to treat the contaminated surface. The steel is washed and the resulting solution is plated on tryptic soy agar (TSA) plates. The GS with the fewest colony forming unit (CFU) formed on TSA is determined to be the most efficient during disinfection. Results show that both GS demonstrate a strong ability to disinfect B. cereus spores. Between the two, GS 9 shows the highest disinfection efficacy by killing approximately 99.5% of spores. This is a drastic improvement over the 0-20% disinfection of the control. Based on this we find that studied GS do have the capacity to act as a disinfectant on stainless steel.

  6. Disinfection of preexisting contamination of bacillus cereus on stainless steel when using glycoconjugate solution

    SciTech Connect

    Pavan, Casey; Tarasenko, Olga

    2011-06-10

    Stainless steel is ubiquitous in our modern world, however it can become contaminated. This can endanger our health. The aim of our study is to disinfect stainless steel using Bacillus cereus as a model organism. Bacillus cereus is a microbe that is ubiquitous in nature, specifically soil. B. cereus is known to cause illness in humans. To prevent this, we propose to use a glycoconjugate solution (GS) for disinfection of stainless steel after it is contamination by B. cereus spores. In this study, two GS (9, 10) were tested for disinfection effectiveness on B. cereus spores on the surface of stainless steel foil (AISI-Series 200/300/400, THERMA-FOIL, Dayville, CT 0241). The disinfection rate of each GS was assessed by exposing the steel surface to B. cereus spores first and allowing them to settle for 24 hours. GS was used to treat the contaminated surface. The steel is washed and the resulting solution is plated on tryptic soy agar (TSA) plates. The GS with the fewest colony forming unit (CFU) formed on TSA is determined to be the most efficient during disinfection. Results show that both GS demonstrate a strong ability to disinfect B. cereus spores. Between the two, GS 9 shows the highest disinfection efficacy by killing approximately 99.5% of spores. This is a drastic improvement over the 0-20% disinfection of the control. Based on this we find that studied GS do have the capacity to act as a disinfectant on stainless steel.

  7. Configurable Multi-Purpose Processor

    NASA Technical Reports Server (NTRS)

    Valencia, J. Emilio; Forney, Chirstopher; Morrison, Robert; Birr, Richard

    2010-01-01

    Advancements in technology have allowed the miniaturization of systems used in aerospace vehicles. This technology is driven by the need for next-generation systems that provide reliable, responsive, and cost-effective range operations while providing increased capabilities such as simultaneous mission support, increased launch trajectories, improved launch, and landing opportunities, etc. Leveraging the newest technologies, the command and telemetry processor (CTP) concept provides for a compact, flexible, and integrated solution for flight command and telemetry systems and range systems. The CTP is a relatively small circuit board that serves as a processing platform for high dynamic, high vibration environments. The CTP can be reconfigured and reprogrammed, allowing it to be adapted for many different applications. The design is centered around a configurable field-programmable gate array (FPGA) device that contains numerous logic cells that can be used to implement traditional integrated circuits. The FPGA contains two PowerPC processors running the Vx-Works real-time operating system and are used to execute software programs specific to each application. The CTP was designed and developed specifically to provide telemetry functions; namely, the command processing, telemetry processing, and GPS metric tracking of a flight vehicle. However, it can be used as a general-purpose processor board to perform numerous functions implemented in either hardware or software using the FPGA s processors and/or logic cells. Functionally, the CTP was designed for range safety applications where it would ultimately become part of a vehicle s flight termination system. Consequently, the major functions of the CTP are to perform the forward link command processing, GPS metric tracking, return link telemetry data processing, error detection and correction, data encryption/ decryption, and initiate flight termination action commands. Also, the CTP had to be designed to survive and

  8. Surface detail reproduction and dimensional accuracy of molds: influence of disinfectant solutions and elastomeric impression materials.

    PubMed

    Guiraldo, Ricardo D; Berger, Sandrine B; Siqueira, Ronaldo Mt; Grandi, Victor H; Lopes, Murilo B; Gonini-Júnior, Alcides; Caixeta, Rodrigo V; de Carvalho, Rodrigo V; Sinhoreti, Mário Ac

    2017-04-01

    This study compared the surface detail reproduction and dimensional accuracy of molds after disinfection using 2% sodium hypochlorite, 2% chlorhexidine digluconate or 0.2% peracetic acid to those of molds that were not disinfected, for four elastomeric impression materials: polysulfide (Light Bodied Permlastic), polyether (Impregum Soft), polydimethylsiloxane (Oranwash L) andpolyvinylsiloxane (Aquasil Ultra LV). The molds were prepared on a matrix by applying pressure, using a perforated metal tray. The molds were removed following polymerization and either disinfected (by soaking in one of the solutions for 15 minutes) or not disinfected. The samples were thus divided into 16 groups (n=5). Surface detail reproduction and dimensional accuracy were evaluated using optical microscopy to assess the 20-μm line over its entire 25 mm length. The dimensional accuracy results (%) were subjected to analysis of variance (ANOVA) and the means were compared by Tukey's test (a=5%). The 20-μm line was completely reproduced by all elastomeric impression materials, regardless of disinfection procedure. There was no significant difference between the control group and molds disinfected with peracetic acid for the elastomeric materials Impregum Soft (polyether) and Aquasil Ultra LV (polyvinylsiloxane). The high-level disinfectant peracetic acid would be the choice material for disinfection. Sociedad Argentina de Investigación Odontológica.

  9. Effect of disinfecting solutions on accuracy of alginate and elastomeric impressions.

    PubMed

    Peutzfeldt, A; Asmussen, E

    1989-10-01

    The effect of immersion in six disinfecting solutions on the accuracy of 10 impression materials was investigated. Impressions were taken of a truncated steel cone. After setting, the impressions were either stored at room temperature for 24 h, for control, or immediately immersed in a disinfecting agent for 60 min (in one case 10 min), and after 24 h poured with gypsum. A steel ring fitting the steel cone was placed on the resulting dies, and the discrepancy between the top surface of the ring and the die was measured. From these measurements the deviation between the base diameter of the die and of the impression was calculated to express the inaccuracy. All impressions except some in Blueprint exhibited a net shrinkage, giving rise to too large die stones and incomplete seating of the steel ring. Blueprint impressions, however, occasionally swelled and resulted in too small die stones and "overseating" of the steel ring. The disinfecting solutions had no significant impact on two impression materials. For the remaining eight materials the accuracy was decreased, increased, or unaffected by the immersion. Generally, the accuracy of the alginates investigated were more affected by the disinfecting solutions than were the elastomeric impression materials. The accuracy of the three alginates was drastically impaired by immersion in 70% ethanol, whereas the remaining five disinfecting solutions had a smaller, though sometimes statistically significant, effect on the accuracy. For the elastomeric materials only a few specific combinations of impression material and disinfecting solution reduced the accuracy.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Effect of disinfecting solutions on surface texture of alginate and elastomeric impressions.

    PubMed

    Peutzfeldt, A; Asmussen, E

    1990-02-01

    The effect of immersion in six disinfecting solutions on the surface texture of 10 impression materials was investigated. Assessment of the surface texture was based on measurement of the ability to reproduce fine detail. Impressions were taken of a roughness standard, i.e. a steel block with known roughness. After setting, the impressions were either stored at room temperature for 24 h, for control, or immediately immersed in a disinfecting agent for 60 min (in one case 10 min), and after 24 h poured with gypsum. After another 24 h, the roughness of the dies was recorded with a profilometer. Three addition-curing silicones were left unaltered by disinfection. For the remaining seven materials, the ability of detail reproduction was changed for some of the combinations of impression material and disinfecting solution. In general, this meant a reduction of detail reproduction, but occasionally an improvement of the surface texture resulted from disinfection. Changes in surface texture were most often brought about by a solution of chlorinated trisodium phosphate. It was concluded that elastomeric impression materials reproduced fine detail better than did alginates and that both types of impression material may be immersed in specific disinfecting solutions for as long as 1 h without the surface texture being impaired.

  11. Multi-Purpose Logistics Module Briefing

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Silvanna Rabbi, MPLM Program Manager, Italian Space Agency, gives an overview of the Multi-Purpose Logistics Module (MPLM) in a prelaunch press conference. She describes the objectives, construction, specifications, and purpose of the three Italian-built modules, Leonardo, Rafaello, and Donatello. Ms. Rabbi then answers questions from the press.

  12. Multi-Purpose Logistics Module Briefing

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Silvanna Rabbi, MPLM Program Manager, Italian Space Agency, gives an overview of the Multi-Purpose Logistics Module (MPLM) in a prelaunch press conference. She describes the objectives, construction, specifications, and purpose of the three Italian-built modules, Leonardo, Rafaello, and Donatello. Ms. Rabbi then answers questions from the press.

  13. Disinfection of upper gastrointestinal fibreoptic endoscopy equipment: an evaluation of a cetrimide chlorhexidine solution and glutaraldehyde.

    PubMed Central

    Carr-Locke, D L; Clayton, P

    1978-01-01

    There is little information available on the bacteriological contamination of upper gastrointestinal fibreoptic endoscopes during routine use and the effects of 'disinfecting solutions'. A bacteriological evaluation was therefore made of cleaning an endoscope and its ancillary equipment with (1) water, (2) an aqueous solution of 1% cetrimide with 0.1% chlorhexidine, and (3) activated aqueous 2% glutaraldehyde. All equipment, but particularly the endoscope itself, was found to be heavily contaminated after use with a wide variety of organisms of which 53% were Gram positive. Cleaning the endoscope and ancillary equipment with water and the cetrimide/chlorhexidine solution alone or in combination was inadequate to produce disinfection but immersion in glutaraldehyde for two minutes consistently produced sterile cultures with our sampling technique. A rapid and simple method for disinfection of endoscopic equipment is therefore recommended and we think this is especially suitable for busy endoscopy units. Images Figure PMID:101424

  14. High-level disinfection with 2% alkalinized glutaraldehyde solution for reuse of laparoscopic disposable plastic trocars.

    PubMed

    Gundogdu, H; Ocal, K; Caglikulekci, M; Karabiber, N; Bayramoglu, E; Karahan, M

    1998-02-01

    The reusability of disposable plastic trocars after high-level disinfection by alkalinized 2% glutaraldehyde solution was examined in a prospective study from the point of view of infection risk in order to determine the safety and economic benefits. For this purpose, 45 laparoscopic cholecystectomy cases were analyzed microbiologically and clinically. In 30 cases, trocars subjected to 15 min of disinfection by glutaraldehyde were used. In the remaining 15 cases, new trocars were used and a control group was established. In total, eight culture samples were taken from trocars, laparoscope (as it is disinfected by the same method), glutaraldehyde solution and umbilicus of the patients preoperatively; and from the bile in the gallbladder, peritoneal lavage fluid, and epigastric and umbilical incisions postoperatively. Only one of the disinfected trocars yielded a culture-positive result. No culture-positive results were found in the samples taken from laparoscope, glutaraldehyde, and epigastric incisions. Culture-positive results were obtained in 11 cases at the umbilicus, in one case at the peritoneal lavage and in one case at the umbilical incision. None of the patients had infection at the wound site or intra-abdominally. In conclusion, we have shown that disposable plastic trocars subjected to high-level disinfection can be reused safely without infection risk and that cost can be reduced.

  15. 9 CFR 96.14 - Uncertified casings; disinfection with saturated brine solution.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Uncertified casings; disinfection with saturated brine solution. 96.14 Section 96.14 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL...

  16. 9 CFR 96.14 - Uncertified casings; disinfection with saturated brine solution.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Uncertified casings; disinfection with saturated brine solution. 96.14 Section 96.14 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL...

  17. [Fiberoptic bronchoscope disinfection with glutaraldehyde phenolate in 1:8 solution].

    PubMed

    Rodríguez-Froján, G; Castella, J; Puzo, C; Coll, P; Garrigó, M; Moreno, C; Burgués, C; Vázquez, N

    1994-12-01

    We evaluated the efficacy of phenolated glutaraldehyde in a 1:8 solution for the disinfection of bronchofibroscopes that were highly contaminated with Serratia marcescens and Pseudomonas aeruginosa. An Olympus BF-P10 bronchofibroscope was contaminated with artificial samples containing one of the aforementioned microorganisms in concentrations nearing 10(8) colony forming units per milliliter (cfu/ml). The instruments were then washed with soap and water and submerged in a 1:8 solution of phenolated glutaraldehyde. Samples were taken for culturing after contamination, after washing, and after 10, 15 and 30 min in the disinfectant solution. The level of cfu/ml in the cultures was measured and the definition of failure-to-disinfect was a finding of > or = 1 cfu/ml after each experimental procedure. Twenty procedures, 10 for each microorganism, were carried out. Washing of the bronchofibroscope afforded significant elimination of microorganisms and no colony growth was observed in cultures after 10 min submersion in phenolated glutaraldehyde. We conclude that immersion in a 1:8 solution of phenolated glutaraldehyde after careful washing is a valid way to disinfect bronchofibroscopes that are highly contaminated with S. marcescens and P. aeruginosa.

  18. Evaluation of the antiviral activity of a green tea solution as a hand-wash disinfectant.

    PubMed

    Shin, Woo-Jin; Kim, Young-Kyung; Lee, Kwang-Hee; Seong, Baik-Lin

    2012-01-01

    Based on the broad-spectrum antiviral effect of green tea catechins, we established an experimental skin contact model for influenza virus transmission and evaluated the use of a green tea solution as a first-hand disinfectant. The infectivity of the virus on the skin cell layer became obsolete when washed with the green tea solution. The skin contact model could be applied to develop non-pharmaceutical intervention measures for reducing human transmission of the influenza virus.

  19. Electronic multi-purpose material level sensor

    DOEpatents

    McEwan, T.E.

    1997-03-11

    The present electronic multi-purpose material level sensor is based on time domain reflectometry (TDR) of very short electrical pulses. Pulses are propagated along a transmission line that is partially immersed in a liquid, powder, or other substance such as grain in a silo. The time difference of the reflections at the start of the transmission line and the air/liquid interface are used to determine levels to better than 0.01 inch. The sensor is essentially independent of circuit element and temperature variations, and can be mass produced at an extremely low price. The transmission line may be a Goubau line, microstrip, coaxial cable, twin lead, CPS or CPW, and may typically be a strip placed along the inside wall of a tank. The reflected pulses also contain information about strata within the liquid such as sludge-build-up at the bottom of an oil tank. 9 figs.

  20. Electronic multi-purpose material level sensor

    DOEpatents

    McEwan, Thomas E.

    1997-01-01

    The present electronic multi-purpose material level sensor is based on time domain reflectometry (TDR) of very short electrical pulses. Pulses are propagated along a transmission line that is partially immersed in a liquid, powder, or other substance such as grain in a silo. The time difference of the reflections at the start of the transmission line and the air/liquid interface are used to determine levels to better than 0.01 inch. The sensor is essentially independent of circuit element and temperature variations, and can be mass produced at an extremely low price. The transmission line may be a Goubau line, microstrip, coaxial cable, twin lead, CPS or CPW, and may typically be a strip placed along the inside wall of a tank. The reflected pulses also contain information about strata within the liquid such as sludge-build-up at the bottom of an oil tank.

  1. Phytochemical profiling as a solution to palliate disinfectant limitations.

    PubMed

    Malheiro, J; Gomes, I; Borges, A; Bastos, M M S M; Maillard, J-Y; Borges, F; Simões, M

    2016-10-01

    The indiscriminate use of biocides for general disinfection has contributed to the increased incidence of antimicrobial tolerant microorganisms. This study aims to assess the potential of seven phytochemicals (tyrosol, caffeic acid, ferulic acid, cinnamaldehyde, coumaric acid, cinnamic acid and eugenol) in the control of planktonic and sessile cells of Staphylococcus aureus and Escherichia coli. Cinnamaldehyde and eugenol showed antimicrobial properties, minimum inhibitory concentrations of 3-5 and 5-12 mM and minimum bactericidal concentrations of 10-12 and 10-14 mM against S. aureus and E. coli, respectively. Cinnamic acid was able to completely control adhered bacteria with effects comparable to peracetic acid and sodium hypochlorite and it was more effective than hydrogen peroxide (all at 10 mM). This phytochemical caused significant changes in bacterial membrane hydrophilicity. The observed effectiveness of phytochemicals makes them interesting alternatives and/or complementary products to commonly used biocidal products. Cinnamic acid is of particular interest for the control of sessile cells.

  2. EFFECT OF 2% IODINE DISINFECTING SOLUTION ON BOND STRENGTH TO DENTIN

    PubMed Central

    da Silva, Nelson Renato Franca Alves; Calamia, Christine S.; Coelho, Paulo G; Carrilho, Marcela Rocha de Oliveira; de Carvalho, Ricardo Marins; Caufield, Page; Thompson, Van P.

    2006-01-01

    Introduction: Disinfection of dentin surfaces is desirable so long as it does not interfere with subsequent bonding of adhesive resins. Objective: To test the null hypothesis that bond strengths to dentin are not affected by previous application of an iodine disinfecting solution. Materials and Methods: Twenty-four extracted non-carious molars were selected. Occlusal enamel was removed producing a flat dentin substrate. Test teeth were all treated with 2% Iodine disclosing/disinfecting solution (I2DDS) for 20 sec and rinsed for 20 sec followed by the application of self- or total- etching bonding systems, generating five adhesive groups (n=3): Single Bond;; Prime & Bond NT; Clearfil SE Bond; Opti-Bond Plus. The control groups (n=3 per adhesive) had no disclosing/disinfectant application prior to adhesive application. A 4-mm thick resin restoration was built up on each tooth for microtensile testing. Statistical analyses between experimental and control groups were performed by student's t-test (α = 0.05). Results: In general, experimental groups (previously treated with I2DDS) showed significantly lower bond strength values when compared with their respective controls (p<0.05), except for group Prime &Bond I2 that did not significantly differ from its control (p>0.05). Conclusion: Acetone-base adhesive systems seem not to be affected by the application of I2DDS prior to etching and bonding procedures. PMID:19089238

  3. Efficacy of Korean Multipurpose Contact Lens Disinfecting Solutions against Acanthamoeba castellanii

    PubMed Central

    Moon, Eun-Kyung; Park, Hye-Ryun; Quan, Fu-Shi; Kong, Hyun-Hee

    2016-01-01

    Acanthamoeba keratitis has been increasing in recent years. Main risk factors are contact lens wear and their cleaning solutions. Most contact lens wearers use multipurpose disinfecting solutions (MPDS) for cleansing and disinfecting microorganisms because of its convenience. We determined amoebicidal effects of MPDS made in Korea and their cytotoxicity on human corneal epithelium cells. Fifteen commercial MPDS (A to O) were tested for their amoebicidal effects on Acanthamoeba castellanii trophozoites and cysts by using a most probable number (MPN) technique. Among them, 7 kinds of MPDS showed little or no amoebicidal effects for 24 hr exposure. Solutions A, B, G, H, L, and O showed positive amoebicidal effects, and solutions M and N killed almost all trophozoites and cysts after 24 hr exposure. However, 50%-N solution showed 56% cytotoxicity on human corneal epithelial cells within 4 hr exposure, and 50%-O solution also showed 62% cytotoxicity on human cells within 4 hr exposure. Solution A did not show any cytotoxicity on human cells. These results revealed that most MPDS made in Korea were ineffective to kill Acanthamoeba. The solutions having amoebicidal activity also showed high levels of cytotoxicity on human corneal epithelial cells. New formulations for improved MPDS that are amoebicidal but safe for host cells are needed to prevent Acanthamoeba keratitis. PMID:28095653

  4. Flow Cytometry for Determination of the Efficacy of Contact Lens Disinfecting Solutions against Acanthamoeba spp.

    PubMed Central

    Borazjani, Roya N.; May, Lauren L.; Noble, Judith A.; Avery, Simon V.; Ahearn, Donald G.

    2000-01-01

    Flow cytometric analyses of cellular staining with fluorescent viability dyes and direct microscopic observations of methylene blue exclusion were compared for evaluation of the effects of a chlorhexidine gluconate-based contact lens disinfectant solution and a polyhexamethylene biguanide solution against cysts and trophozoites of Acanthamoeba castellanii and Acanthamoeba polyphaga. The flow cytometric procedure with propidium iodide (used to stain dead cells) indicated that more than 90% of trophozoites of both species (inocula of 105 to 106/ml) at 22°C lost their viability after 4 h of exposure to chlorhexidine. When propidium iodide was used in combination with fluorescein diacetate (for live cells), the apparent number of propidium iodide-stained cells was reduced, but the relative efficacies of the two biguanide solutions appeared unchanged from those evident with the single dyes; the chlorhexidine solution was more effective than the polyhexamethylene biguanide solution. Similar data were obtained with the more cumbersome methylene blue exclusion procedure. Flow cytometric analyses provided a statistically reproducible and rapid procedure for determining the relative antiamoebal efficacies of the disinfecting solutions. PMID:10698771

  5. Disinfection potential of electrolyzed solutions containing sodium chloride at low concentrations.

    PubMed

    Morita, C; Sano, K; Morimatsu, S; Kiura, H; Goto, T; Kohno, T; Hong, W U; Miyoshi, H; Iwasawa, A; Nakamura, Y; Tagawa, M; Yokosuka, O; Saisho, H; Maeda, T; Katsuoka, Y

    2000-03-01

    Electrolyzed products of sodium chloride solution were examined for their disinfection potential against hepatitis B virus (HBV) and human immunodeficiency virus (HIV) in vitro. Electrolysis of 0.05% NaCl in tap water was carried out for 45 min at room temperature using a 3 A electric current in separate wells installed with positive and negative electrodes. The electrolyzed products were obtained from the positive well. The oxidation reduction potential (ORP), pH and free chlorine content of the product were 1053 mV, pH 2.34 and 4.20 ppm, respectively. The products modified the antigenicity of the surface protein of HBV as well as the infectivity of HIV in time- and concentration-dependent manner. Although the inactivating potential was decreased by the addition of contaminating protein, recycling of the product or continuous addition of fresh product may restore the complete disinfection against bloodborne pathogens.

  6. Disinfection of E. coli by nonthermal microplasma electrolysis in normal saline solution

    NASA Astrophysics Data System (ADS)

    Sakiyama, Yukinori; Tomai, Takaaki; Miyano, Masaru; Graves, David B.

    2009-04-01

    We present a unique method to inactivate microorganisms in 0.9% NaCl solution (normal saline solution) by means of microplasmas. The device consists of a thin titanium wire covered by a glass tube for insulation except the tip and a ground electrode. Application of an asymmetric high-frequency, high voltage results in the formation of microbubbles at both electrodes. Repetitive light emission is observed in the vicinity of the powered electrode. We employed E. coli bacteria to investigate the disinfection efficiency of the device. More than 99.5% of E. coli were deactivated in 180 s. The survival curve showed biphasic behavior.

  7. Surface detail reproduction and dimensional accuracy of stone models: influence of disinfectant solutions and alginate impression materials.

    PubMed

    Guiraldo, Ricardo Danil; Borsato, Thaís Teixeira; Berger, Sandrine Bittencourt; Lopes, Murilo Baena; Gonini-Jr, Alcides; Sinhoreti, Mário Alexandre Coelho

    2012-01-01

    This study compared the surface detail reproduction and dimensional accuracy of stone models obtained from molds disinfected with 2% sodium hypochlorite, 2% chlorhexidine digluconate or 0.2% peracetic acid to models produced using molds which were not disinfected, with 3 alginate materials (Cavex ColorChange, Hydrogum 5 and Jeltrate Plus). The molds were prepared over matrix containing 20-, 50-, and 75-µm lines, performed under pressure with perforated metal tray. The molds were removed following gelation and either disinfected (using one of the solutions by spraying followed by storage in closed jars for 15 min) or not disinfected. The samples were divided into 12 groups (n=5). Molds were filled with dental gypsum Durone IV and 1 h after the start of the stone mixing the models were separated from the tray. Surface detail reproduction and dimensional accuracy were evaluated using optical microscopy on the 50-µm line with 25 mm in length, in accordance with the ISO 1563 standard. The dimensional accuracy results (%) were subjected to ANOVA. The 50 µm-line was completely reproduced by all alginate impression materials regardless of the disinfection procedure. There was no statistically significant difference in the mean values of dimensional accuracy in combinations between disinfectant procedure and alginate impression material (p=0.2130) or for independent factors. The disinfectant solutions and alginate materials used in this study are no factors of choice regarding the surface detail reproduction and dimensional accuracy of stone models.

  8. The effect of detergents on the antibacterial activity of disinfecting solutions in dentin.

    PubMed

    Wang, Zhejun; Shen, Ya; Ma, Jingzhi; Haapasalo, Markus

    2012-07-01

    Detergents have been added into different disinfecting solutions to lower their surface tension and to enhance their antibacterial effects. The purpose of this study was to evaluate the effectiveness of dentin disinfection by different antibacterial solutions in the presence and absence of detergents using a novel dentin infection model and confocal laser scanning microscopy (CLSM). Semicylindrical dentin specimens were infected with Enterococcus faecalis by centrifugation according to a previously described protocol. After 1 day of incubation, the infected dentin specimens were subjected to 1 and 3 minutes of exposure to sterile water, 0.1% cetrimide (CTR), 2% sodium hypochlorite (NaOCl), 2% NaOCl + 0.1% CTR, 6% NaOCl, 6% NaOCl + 0.1% CTR, Chlor-Xtra (Vista Dental, Racine, WI), 2% chlorhexidine (CHX), CHX-Plus (Vista Dental, Racine, WI), 2/4% iodine potassium iodide (IPI), and IPI + 0.1% CTR. The specimens were then stained for bacterial viability and examined by CLSM to analyze the proportions of dead and live bacteria inside dentinal tubules. More bacteria in dentin were killed after 3 minutes of exposure than after 1 minute of exposure to the disinfecting solutions in all experimental groups (P < .05). The antibacterial solutions with detergents (0.1% CTR, 2% NaOCl + 0.1% CTR, CHX-Plus, and IPI + 0.1% CTR) showed a statistically higher proportion of dead bacteria than the corresponding solutions without detergents (sterile water, 2% NaOCl, 2% CHX, and IPI) (P < .05) except for the 6% NaOCl group (6% NaOCl, 6% NaOCl + 0.1% CTR, and Chlor-Xtra) (P > .05). Six percent NaOCl, 6% NaOCl + 0.1% CTR, and Chlor-Xtra were the most effective solutions, killing over 45% and 65% of the bacteria after 1 and 3 minutes of exposure, respectively. Only 3% to 4% of the bacteria were dead in the sterile water group, whereas 0.1% CTR alone was able to kill 24% to 36% of the E. faecalis cells. The addition of detergents in the disinfecting solutions used in the present study

  9. Resistance of Acanthamoeba cysts to disinfection in multiple contact lens solutions.

    PubMed

    Johnston, Stephanie P; Sriram, Rama; Qvarnstrom, Yvonne; Roy, Sharon; Verani, Jennifer; Yoder, Jonathan; Lorick, Suchita; Roberts, Jacquelin; Beach, Michael J; Visvesvara, Govinda

    2009-07-01

    Acanthamoebae are free-living amoebae found in the environment, including soil, freshwater, brackish water, seawater, hot tubs, and Jacuzzis. Acanthamoeba species can cause keratitis, a painful vision-threatening infection of the cornea, and fatal granulomatous encephalitis in humans. More than 20 species of Acanthamoeba belonging to morphological groups I, II, and III distributed in 15 genotypes have been described. Among these, Acanthamoeba castellanii, A. polyphaga, and A. hatchetti are frequently identified as causing Acanthamoeba keratitis (AK). Improper contact lens care and contact with nonsterile water while wearing contact lenses are known risk factors for AK. During a recent multistate outbreak, AK was found to be associated with the use of Advanced Medical Optics Complete MoisturePlus multipurpose contact lens solution, which was hypothesized to have had insufficient anti-Acanthamoeba activity. As part of the investigation of that outbreak, we compared the efficacies of 11 different contact lens solutions against cysts of A. castellanii, A. polyphaga, and A. hatchetti (the isolates of all species were genotype T4), which were isolated in 2007 from specimens obtained during the outbreak investigation. The data, generated with A. castellanii, A. polyphaga, and A. hatchetti cysts, suggest that the two contact lens solutions containing hydrogen peroxide were the only solutions that showed any disinfection ability, with 0% and 66% growth, respectively, being detected with A. castellanii and 0% and 33% growth, respectively, being detected with A. polyphaga. There was no statistically significant difference in disinfection efficacy between the 11 solutions for A. hatchetti.

  10. Comparison of Hydrogen Peroxide Contact Lens Disinfection Systems and Solutions against Acanthamoeba polyphaga

    PubMed Central

    Hughes, Reanne; Kilvington, Simon

    2001-01-01

    Acanthamoeba is a free-living amoeba causing a potentially blinding infection of the cornea. Contact lens wearers are most at risk and account for some 95% of cases. Hydrogen peroxide is used for contact lens disinfection due to its broad antimicrobial activity. Lenses must be neutralized before use to avoid pronounced stinging and possible corneal damage. Neutralization is achieved by adding a catalyst during the disinfection process (one-step) or afterwards (two-step). Here, the activities of commercial peroxide systems and individual solutions against trophozoites and cysts of Acanthamoeba polyphaga were compared. All disinfection systems were active against trophozoites, giving a ≥3-log (99.9%) kill within 1 h. Of the four one-step systems, only one showed some cysticidal activity, giving a 1.28 ± 0.41-log reduction. Both two-step systems were cysticidal, giving a ≥3-log kill at 4 h. All system peroxide solutions were cysticidal, giving a ≥3-log kill by 4 to 6 h. Variation in the cysticidal rate was observed with two solutions that gave a 1.8- to 2.1-log kill at 4 h compared with 3.0 to 4.0 for the rest (P < 0.05). No cysticidal activity was found with the peroxigen sodium perborate or the contact lens protein remover subtilisin A. Two-step systems are cysticidal providing contact times of at least 4 h are employed. Variation in cyst killing occurs between peroxide solutions, possibly due to formulation differences. One-step systems are less effective against Acanthamoeba cysts due to rapid peroxide neutralization. The cysticidal activity of one-step systems could be improved if neutralization rates were retarded. PMID:11408220

  11. Dimensional changes in alginate impression during immersion in a disinfectant solution.

    PubMed

    Muzaffar, Danish; Ahsan, Syed Hammad; Afaq, Ashar

    2011-08-01

    To determine the effect of a commercially available disinfectant solution (Perform ID) on the dimensional stability of two different commercially available alginate impression materials. Linear changes in standardized impression samples (1.5 mm & 3.0 mm thickness) made in two commercial alginates were recorded at 5 minute intervals, over a period of an hour after immersion in a disinfectant. The alginate impression samples were prepared placing the alginate mixes into a wax mould. After the material had set, each of the samples was removed from the mould. It was then placed in a Polytetraflouroethylene (PTFE) trough before measuring the dimensional changes using a Chesterman travelling microscope. 3mm BluePrint Cremix showed greater shrinkage than 3mm Hydrogum. While, 1.5mm Hydrogum appeared to have uniformly greater shrinkage as compared to 1.5mm BluePrint Cremix. There was significant difference between 1.5 and 3mm thicknesses of both Hydrogum and BluePrint Cremix (PAIRED SAMPLE t test p < 0.05). The 1.5mm samples showed much higher shrinkage than 3mm samples. Immersion of the alginates in the same disinfectant showed variable linear shrinkage indicating that slight changes in composition could lead to variable results. In addition, there were significant differences in the linear shrinkage between the two thicknesses of the same alginate material; this indicates the possibility of distortion in actual impressions where the geometry is complex.

  12. Fresh-cut product sanitation and wash water disinfection: problems and solutions.

    PubMed

    Gil, Maria I; Selma, Maria V; López-Gálvez, Francisco; Allende, Ana

    2009-08-31

    It is well known that fresh-cut processors usually rely on wash water sanitizers to reduce microbial counts in order to maintain quality and extend shelf-life of the end product. Water is a useful tool for reducing potential contamination but it can also transfer pathogenic microorganisms. Washing with sanitizers is important in fresh-cut produce hygiene, particularly removing soil and debris, but especially in water disinfection to avoid cross-contamination between clean and contaminated product. Most of the sanitizing solutions induce higher microbial reduction after washing when compared to water washing, but after storage, epiphytic microorganisms grow rapidly, reaching similar levels. In fact, despite the general idea that sanitizers are used to reduce the microbial population on the produce, their main effect is maintaining the microbial quality of the water. The use of potable water instead of water containing chemical disinfection agents for washing fresh-cut vegetables is being advocated in some European countries. However, the problems of using an inadequate sanitizer or even none are considered in this manuscript. The need for a standardized approach to evaluate and compare the efficiency of sanitizing agents is also presented. Most new alternative techniques accentuate the problems with chlorine suggesting that the industry should move away from this traditional disinfection agent. However, the use of chlorine based sanitizers are presented as belonging to the most effective and efficient sanitizers when adequate doses are used. In this review improvements in water disinfection and sanitation strategies, including a shower pre-washing step and a final rinse of the produce, are suggested.

  13. Use of 4% Chlorhexidine Detergent Solution (Hibiscrub) and Other Methods of Skin Disinfection

    PubMed Central

    Lowbury, E. J. L.; Lilly, H. A.

    1973-01-01

    In a comparison of three antiseptic detergent preparations for hand washing, Hibiscrub, a 4% chlorhexidine detergent solution, caused a significantly greater estimated immediate reduction of skin flora (86·7% ± 3·0) than was obtained with Dermofax, a 0·75% chlorhexidine detergent solution (55·5% ± 5·1), or with Disadine scrub, a povidone iodine detergent preparation (68% ± 6·8). After six applications the mean estimated reductions of skin flora were 99·2% ± 0·2 for Hibiscrub, 97·7% ± 0·7 for povidone iodine, and 91·8% ± 1·6 for Dermofax. After a series of hand washings with Hibiscrub, as with a hexachlorophane detergent preparation, a further large reduction of skin flora, shown by bacterial counts of hand sampling, was obtained by a second phase of disinfection consisting of two minutes' application on gauze swabs of 0·5% chlorhexidine digluconate in 70% ethanol; a further wash with Hibiscrub, in place of alcoholic chlorhexidine, for the second phase of disinfection caused an increase rather than a reduction in the yield of bacteria on skin sampling. Unlike this “two-phase” disinfection, the application for 30 minutes of compresses soaked in 10% aqueous povidone iodine or in 0·5% aqueous chlorhexidine digluconate did not cause a greater reduction in skin flora than that obtained by the conventional two minutes' application on gauze of 0·5% chlorhexidine in 70% ethanol. Chlorocresol (0·3%) liquid soap (the base used for Ster-Zac liquid hexachlorophane soap) caused a mean reduction of skin flora when used for hand washing of 29% after one application and 72% after six applications spread over two days. This formulation, though less active and more variable as a detergent skin antiseptic than chlorhexidine, hexachlorophane, or povidone iodine detergent preparations, is an inexpensive disinfectant soap which could be useful in catering establishments. Alcoholic cetrimide applied as for disinfection of an operation site caused a reduction of

  14. New formaldehyde base disinfectants.

    NASA Technical Reports Server (NTRS)

    Trujillo, R.; Lindell, K. F.

    1973-01-01

    Preparations of formaldehyde in various organic liquids - ethylene glycol, glycerol, and propylene glycol - serve as effective disinfectants towards microbial vegetative cells and spores. This disinfection is a temperature-dependent process and is manifest when these formaldehyde base disinfectants are dissolved in water. The irritating vapors associated with formaldehyde disinfection are not present in either of these new formaldehyde base disinfectants or in aqueous solutions of them.

  15. New formaldehyde base disinfectants.

    NASA Technical Reports Server (NTRS)

    Trujillo, R.; Lindell, K. F.

    1973-01-01

    Preparations of formaldehyde in various organic liquids - ethylene glycol, glycerol, and propylene glycol - serve as effective disinfectants towards microbial vegetative cells and spores. This disinfection is a temperature-dependent process and is manifest when these formaldehyde base disinfectants are dissolved in water. The irritating vapors associated with formaldehyde disinfection are not present in either of these new formaldehyde base disinfectants or in aqueous solutions of them.

  16. Multi-Purpose Logistics Module (MPLM) Cargo Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Zampiceni, John J.; Harper, Lon T.

    2002-01-01

    This paper describes the New Shuttle Orbiter's Multi- Purpose Logistics Modulo (MPLM) Cargo Heat Exchanger (HX) and associated MPLM cooling system. This paper presents Heat Exchanger (HX) design and performance characteristics of the system.

  17. Multi-Purpose Logistics Module (MPLM) Cargo Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Zampiceni, John J.; Harper, Lon T.

    2002-01-01

    This paper describes the New Shuttle Orbiter's Multi- Purpose Logistics Modulo (MPLM) Cargo Heat Exchanger (HX) and associated MPLM cooling system. This paper presents Heat Exchanger (HX) design and performance characteristics of the system.

  18. Impact of contact lens materials on multipurpose contact lens solution disinfection activity against Fusarium solani.

    PubMed

    Clavet, Charles R; Chaput, Maria P; Silverman, Matthew D; Striplin, Megan; Shoff, Megan E; Lucas, Anne D; Hitchins, Victoria M; Eydelman, Malvina B

    2012-11-01

    To investigate the effects of eight different soft contact lenses on disinfection efficacy of a multipurpose solution (MPS) containing polyhexamethylene biguanide (PHMB) against Fusarium solani. Six silicone hydrogel lenses (galyfilcon A, senofilcon A, comfilcon A, enfilcon A, balafilcon A, and lotrifilcon B) and two conventional hydrogel lenses (polymacon and etafilcon A) were placed in polypropylene lens cases filled with MPS containing 0.0001% PHMB and soaked for 6, 12, 24, 72, and 168 hours. After each interval, depleted MPS from lens cases were removed and assayed for activity against F. solani according to International Organization for Standardization (ISO) 14729 stand-alone procedure. A portion was aliquoted for chemical analysis. Soaking etafilcon A, balafilcon A, and polymacon lenses for 6 hours reduced the concentration of PHMB in MPS by more than half the stated labeled concentration, with concentrations below the limit of detection for etafilcon A-depleted and balafilcon A-depleted solutions after 12 and 72 hours of soaking, respectively. Except for comfilcon A-depleted solutions, all others failed to consistently obtain one log reduction of F. solani. The solutions soaked with etafilcon A, balafilcon A, and polymacon lenses for 24 hours or more lost all or almost all fungicidal activity against F. solani. Over time, the disinfectant uptake by some lenses can significantly reduce the PHMB concentration and the fungicidal activity of the MPS against F. solani. Current ISO methodology does not address the reduction in microbiocidal efficacy when lenses are soaked in MPS. The ISO committee should consider adding "soaking experiments" to quantify the effect that contact lens materials have on the performance of MPSs.

  19. Human resources for maternal health: multi-purpose or specialists?

    PubMed Central

    Fauveau, Vincent; Sherratt, Della R; de Bernis, Luc

    2008-01-01

    A crucial question in the aim to attain MDG5 is whether it can be achieved faster with the scaling up of multi-purpose health workers operating in the community or with the scaling up of professional skilled birth attendants working in health facilities. Most advisers concerned with maternal mortality reduction concur to promote births in facilities with professional attendants as the ultimate strategy. The evidence, however, is scarce on what it takes to progress in this path, and on the 'interim solutions' for situations where the majority of women still deliver at home. These questions are particularly relevant as we have reached the twentieth anniversary of the safe motherhood initiative without much progress made. In this paper we review the current situation of human resources for maternal health as well as the problems that they face. We propose seven key areas of work that must be addressed when planning for scaling up human resources for maternal health in light of MDG5, and finally we indicate some advances recently made in selected countries and the lessons learned from these experiences. Whilst the focus of this paper is on maternal health, it is acknowledged that the interventions to reduce maternal mortality will also contribute to significantly reducing newborn mortality. Addressing each of the seven key areas of work – recommended by the first International Forum on 'Midwifery in the Community', Tunis, December 2006 – is essential for the success of any MDG5 programme. We hypothesize that a great deal of the stagnation of maternal health programmes has been the result of confusion and careless choices in scaling up between a limited number of truly skilled birth attendants and large quantities of multi-purpose workers with short training, fewer skills, limited authority and no career pathways. We conclude from the lessons learnt that no significant progress in maternal mortality reduction can be achieved without a strong political decision to

  20. Human resources for maternal health: multi-purpose or specialists?

    PubMed

    Fauveau, Vincent; Sherratt, Della R; de Bernis, Luc

    2008-09-30

    A crucial question in the aim to attain MDG5 is whether it can be achieved faster with the scaling up of multi-purpose health workers operating in the community or with the scaling up of professional skilled birth attendants working in health facilities. Most advisers concerned with maternal mortality reduction concur to promote births in facilities with professional attendants as the ultimate strategy. The evidence, however, is scarce on what it takes to progress in this path, and on the 'interim solutions' for situations where the majority of women still deliver at home. These questions are particularly relevant as we have reached the twentieth anniversary of the safe motherhood initiative without much progress made. In this paper we review the current situation of human resources for maternal health as well as the problems that they face. We propose seven key areas of work that must be addressed when planning for scaling up human resources for maternal health in light of MDG5, and finally we indicate some advances recently made in selected countries and the lessons learned from these experiences. Whilst the focus of this paper is on maternal health, it is acknowledged that the interventions to reduce maternal mortality will also contribute to significantly reducing newborn mortality. Addressing each of the seven key areas of work--recommended by the first International Forum on 'Midwifery in the Community', Tunis, December 2006--is essential for the success of any MDG5 programme. We hypothesize that a great deal of the stagnation of maternal health programmes has been the result of confusion and careless choices in scaling up between a limited number of truly skilled birth attendants and large quantities of multi-purpose workers with short training, fewer skills, limited authority and no career pathways. We conclude from the lessons learnt that no significant progress in maternal mortality reduction can be achieved without a strong political decision to empower

  1. Additional disinfection with a modified salt solution in a root canal model.

    PubMed

    van der Waal, Suzette V; Oonk, Charlotte A M; Nieman, Selma H; Wesselink, Paul R; de Soet, Johannes J; Crielaard, Wim

    2015-10-01

    The aim of this study is to investigate the disinfecting properties of a modified salt solution (MSS) and calcium hydroxide (Ca(OH)2) in a non-direct-contact ex-vivo model. Seventy-four single-canal roots infected with Enterococcus faecalis were treated with 1% sodium hypochlorite (NaOCl) irrigation or with NaOCl irrigation with subsequent dressing with MSS or Ca(OH)2. After removal of the dressings, the roots were filled with bacterial growth medium and incubated for seven days to enable the surviving bacteria to repopulate the root canal lumen. Growth was determined by sampling the root canals with paper points before treatment (S1), after treatment (S2) and incubation after treatment (S3). The colony forming units were counted at S1 and S2. At S3, growth was determined as no/yes regrowth. The Kruskal-Wallis, McNemar and χ(2) test were used for statistical analyses. At S2, in the NaOCl group, growth was found in 5 of 19 root canals. After the removal of MSS or Ca(OH)2 bacteria were retrieved from one root canal in both groups. At S3, repopulation of the root canals had occurred in 14 of 19 roots after sole NaOCl irrigation, 6 of 20 roots after MSS-dressing and in 14 of 20 roots after Ca(OH)2-dressing. MSS was more effective in preventing regrowth than Ca(OH)2 (P=0.009). The modified salt solution prevented regrowth in roots which indicates that it can eliminate persistent bacteria. Dressing the root canals with Ca(OH)2 did not provide additional disinfection after NaOCl irrigation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Evaluation of povidone-iodine as a disinfectant solution for contact lenses: antimicrobial activity and cytotoxicity for corneal epithelial cells.

    PubMed

    Yanai, Ryoji; Yamada, Naoyuki; Ueda, Kiichi; Tajiri, Motoharu; Matsumoto, Toru; Kido, Keiji; Nakamura, Shigeru; Saito, Fumio; Nishida, Teruo

    2006-05-01

    Povidone-iodine (PVP-I) possesses broad-spectrum antimicrobial activity and is used clinically as a disinfectant. We evaluated the disinfectant properties and safety of PVP-I for use as a contact lens solution. The concentrations of PVP-I required to reduce the number of Staphylococcus aureus or Candida albicans by 3 log units were lower than were those of hydrogen peroxide, polyhexamethylene biguanide (PHMB), and benzalkonium chloride (BAK). The cytotoxicity of PVP-I for cultured human corneal epithelial (HCE) cells was less than that of the other three agents. The safety margin for PVP-I was thus greatest among the tested compounds. PVP-I appears suited for use as a contact lens disinfectant.

  3. Antimicrobial activity of conventional and plant-extract disinfectant solutions on microbial biofilms on a maxillofacial polymer surface.

    PubMed

    Guiotti, Aimée Maria; Cunha, Bruno Guandalini; Paulini, Marcela Borghi; Goiato, Marcelo Coelho; Dos Santos, Daniela Micheline; Duque, Cristiane; Caiaffa, Karina Sampaio; Brandini, Daniela Atili; Narciso de Oliveira, Derly Tescaro; Brizzotti, Natália Seron; Gottardo de Almeida, Margarete Teresa

    2016-07-01

    Dentists often note problems with infection in patients with maxillofacial prostheses. Conventional disinfection protocols are not always effective and may alter the properties of the polymer used in the prosthesis. Thus, the search for improved disinfection methods is important. The purpose of this in vitro study was to evaluate and compare the antimicrobial activity of conventional disinfectant solutions (water and neutral soap and 4% chlorhexidine) and plant extracts (Cymbopogon nardus and Hydrastis canadensis) on specimens of maxillofacial silicone contaminated with Candida albicans and Staphylococcus aureus biofilms. Seventy-two silicone (MDX4-4210) specimens were fabricated (5×2 mm) and sterilized. Thirty-six were contaminated with C albicans (10(6) cells/mL) and 36 with S aureus (10(8) cells/mL) to evaluate the antimicrobial activity of the cleaning protocols. After incubation (37°C/72 hours), the specimens were divided into 5 groups: not disinfected (positive control), soaking in saline solution for 10 minutes, soaking in 4% chlorhexidine for 10 minutes, soaking in C nardus for 10 minutes, soaking in H canadensis for 10 minutes, and washing by hand with water and neutral soap for 30 seconds. The viability of cells was evaluated by XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) assay and by scanning electron microscope analysis. The results were analyzed by ANOVA and the Tukey HSD test (α=.05). All disinfection solutions provided a statistically significant reduction in biofilm viability compared with the control group for both microorganisms (P<.05). Washing with water and neutral soap was significantly more effective in reducing biofilm viability than immersion in the disinfection solutions, with persistence of viable microorganisms between 1.05% for C albicans and 0.62% for S aureus after this cleaning protocol. Photomicrographs revealed that 4% chlorhexidine altered the surface of the polymer. Within the limitations of

  4. OCRWM Bulletin: Westinghouse begins designing multi-purpose canister

    SciTech Connect

    1995-09-01

    This publication consists of two parts: OCRWM (Office of Civilian Radioactive Waste Management) Bulletin; and Of Mountains & Science which has articles on the Yucca Mountain project. The OCRWM provides information about OCRWM activities and in this issue has articles on multi-purpose canister design, and transportation cask trailer.

  5. ISS Expedition 18 Multi Purpose Logistics Module (MPLM) Interior

    NASA Image and Video Library

    2008-11-19

    ISS018-E-009227 (18 Nov. 2008) --- Astronaut Donald Pettit, STS-126 mission specialist, floats in the Leonardo Multi-Purpose Logistics Module attached to the Earth-facing port of the International Space Station's Harmony node while Space Shuttle Endeavour is docked with the station.

  6. ISS Expedition 18 Multi Purpose Logistics Module (MPLM) Interior

    NASA Image and Video Library

    2008-11-19

    ISS018-E-009225 (18 Nov. 2008) --- Astronaut Shane Kimbrough, STS-126 mission specialist, floats in the Leonardo Multi-Purpose Logistics Module attached to the Earth-facing port of the International Space Station's Harmony node while Space Shuttle Endeavour is docked with the station.

  7. The effect of contact lens materials on disinfection activity of polyquaternium-1 and myristamidopropyl dimethylamine multipurpose solution against Staphylococcus aureus.

    PubMed

    Shoff, Megan E; Lucas, Anne D; Phillips, K Scott; Brown, Jennifer N; Hitchins, Victoria M; Eydelman, Malvina B

    2012-11-01

    This study examined the interaction of seven different lens materials with a multipurpose solution (MPS) containing the disinfectants polyquaternium-1 (0.001%) and myristamidopropyl dimethylamine (0.0005%). The objective of this study was to determine whether the different lens materials affect the concentration of a disinfectant in this commercially available MPS and the efficacy of the disinfectant against Staphylococcus aureus. Silicone hydrogel lenses (galyfilcon A, senofilcon A, comfilcon A, enfilcon A, balafilcon A, and lotrafilcon B) and a conventional hydrogel lens (etafilcon A) were soaked in polypropylene lens cases filled with commercially available MPS containing 0.001% polyquaternium-1 and 0.0005% myristamidopropyl dimethylamine for 6, 12, 24, 72, and 168 hours. Empty lens cases were also filled with MPS. After each time point, solutions from cases containing the seven types of lenses and controls were assayed for activity against S. aureus according to International Standards Organization 14729 standard with modifications. Test solutions were analyzed for polyquaternium-1 and myristamidopropyl dimethylamine concentration at each time point. The concentration of polyquaternium-1 and myristamidopropyl dimethylamine remaining in the lens cases was reduced only slightly over time. Storage with the lenses did not adversely affect biocidal efficacy of the solution, and in some cases, it was significantly better (P=0.0029). The efficacy of this polyquaternium-1 and myristamidopropyl dimethylamine MPS to kill S. aureus was not adversely affected by the presence of lens materials soaking in the cases. Thus, current methods for performing solution antimicrobial testing should be reevaluated.

  8. [Disinfection efficacy of hand hygiene based on chlorhexidine gluconate content and usage of alcohol-based hand-rubbing solution].

    PubMed

    Tanaka, Ippei; Watanabe, Kiyoshi; Nakaminami, Hidemasa; Azuma, Chihiro; Noguchi, Norihisa

    2014-01-01

    Recently, the procedure for surgical hand hygiene has been switching to a two-stage method and hand-rubbing method from the traditional hand-scrubbing method. Both the two-stage and hand-rubbing methods use alcohol-based hand-rubbing after hand washing. The former requires 5 min of antiseptic hand washing, and the latter 1 min of nonantiseptic hand washing. For a prolonged bactericidal effect in terms of surgical hand hygiene, chlorhexidine gluconate (CHG) has been noted due to its residual activity. However, no detailed study comparing the disinfection efficacy and prolonged effects according to different contents of CHG and the usage of alcohol-based hand-rubbing has been conducted. The glove juice method is able to evaluate disinfection efficacy and prolonged effects of the disinfectants more accurately because it can collect not only transitory bacteria but also normal inhabitants on hands. In the present study, we examined the disinfection efficacy and prolonged effects on alcohol-based hand-rubbing containing CHG by six hand-rubbing methods and three two-stage methods using the glove juice method. In both methods, 3 mL (one pump dispenser push volume) alcohol-based hand-rubbing solution containing 1% (w/v) CHG showed the highest disinfection efficacy and prolonged effects, and no significant difference was found between the hand-rubbing and two-stage methods. In the two methods of hand hygiene, the hand-rubbing method was able to save time and cost. Therefore, the data strongly suggest that the hand-rubbing method using a one pump dispenser push volume of alcohol-based hand-rubbing solution containing 1% (w/v) CHG is suitable for surgical hand hygiene.

  9. Evaluation of safety and efficacy of a new multipurpose disinfecting solution on silicone hydrogel contact lenses☆

    PubMed Central

    Pinto-Fraga, José; Blázquez Arauzo, Francisco; Urbano Rodríguez, Rubén; González-García, María J.

    2014-01-01

    Purpose To evaluate the safety and efficacy of a new multipurpose disinfecting solution (MPDS) with a formulation that includes aloe vera on its composition. Methods This is a prospective, randomized, double-masked clinical trial with a crossover design that included seven examinations. Two different MPDSs, Avizor Alvera® (study solution) and All Clean Soft® (control solution), each were used for 1 month. Comfilcon A silicone hydrogel contact lenses were used during the trial. The main outcome variables were corneal staining and deposits on the surfaces of the contact lenses. Other parameters including ocular surface response, contact lens wettability, user satisfaction, and adverse events, were analyzed according to the International Organization for Standardization (ISO) 11980:2010 guidance for clinical investigation. Results Twenty subjects (10 women, 10 men) (mean age, 27.7 ± 5.6 years; range, 20–41) were included. No differences between both MPDSs were found in the percentage of subjects with corneal staining >0 at day 30 (study: 35%, control: 50%; p = 0.46); neither in the percentage of subjects with deposits on the surface of the contact lens >0 at day 30 (study: 26.32%, control: 52.63%; p = 0.18). The study MPDS received higher rates in comfort (study: 8.14 ± 1.09, control: 7.94 ± 0.92; p = 0.56) and satisfaction at day 30 (study: 8.63 ± 0.91, control: 8.29 ± 0.80; p = 0.19), however the scores were not significantly different with the control MPDS. Conclusions The clinical trial showed that the study MPDS is safe, efficient, and has acceptable physiologic tolerance, according to the ISO 11980:2010 guidance for clinical investigation. PMID:25649640

  10. Evaluation of safety and efficacy of a new multipurpose disinfecting solution on silicone hydrogel contact lenses.

    PubMed

    Pinto-Fraga, José; Blázquez Arauzo, Francisco; Urbano Rodríguez, Rubén; González-García, María J

    2015-01-01

    To evaluate the safety and efficacy of a new multipurpose disinfecting solution (MPDS) with a formulation that includes aloe vera on its composition. This is a prospective, randomized, double-masked clinical trial with a crossover design that included seven examinations. Two different MPDSs, Avizor Alvera® (study solution) and All Clean Soft® (control solution), each were used for 1 month. Comfilcon A silicone hydrogel contact lenses were used during the trial. The main outcome variables were corneal staining and deposits on the surfaces of the contact lenses. Other parameters including ocular surface response, contact lens wettability, user satisfaction, and adverse events, were analyzed according to the International Organization for Standardization (ISO) 11980:2010 guidance for clinical investigation. Twenty subjects (10 women, 10 men) (mean age, 27.7±5.6 years; range, 20-41) were included. No differences between both MPDSs were found in the percentage of subjects with corneal staining >0 at day 30 (study: 35%, control: 50%; p=0.46); neither in the percentage of subjects with deposits on the surface of the contact lens >0 at day 30 (study: 26.32%, control: 52.63%; p=0.18). The study MPDS received higher rates in comfort (study: 8.14±1.09, control: 7.94±0.92; p=0.56) and satisfaction at day 30 (study: 8.63±0.91, control: 8.29±0.80; p=0.19), however the scores were not significantly different with the control MPDS. The clinical trial showed that the study MPDS is safe, efficient, and has acceptable physiologic tolerance, according to the ISO 11980:2010 guidance for clinical investigation. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  11. Influence on the generation of disinfection byproducts in a tannic acid solution by aluminum ions.

    PubMed

    Shen, Hong; Chen, Xin; Chen, Hongbin

    2016-08-17

    Aluminum (Al) commonly exists in natural waters, and its salts are often used as coagulants in drinking water treatment. Therefore, associated with the security of drinking water, functions of Al ions (Al(3+)) on generation of disinfection byproducts (DBPs) should not be ignored. This study focuses on DBPs and the carcinogenic factor of chlorinated water samples after the addition of Al(3+) with different Al(3+)/initial tannic acid molar ratios. The results imply that Al(3+) acts as a promoter of haloacetic acids (HAAs) and an inhibitor of trihalomethanes (THMs) when tannic acid is selected as model compound of natural organic matter during chlorination. Depending on the results of size exclusion chromatography and ultraviolet spectrophotometer, an equilibrium system can be assumed between hydrolysis and flocculation in tannic acid solution with Al(3+). Furthermore, influences on the equilibrium system for Al(3+) addition may result in various effects on generation and distribution ratios of THMs and HAAs during chlorination. Finally, according to the analyses of a fluorescence spectrophotometer, it is demonstrated that the presence of Al(3+) helps to increase precursors of DBPs (humic acid-like organics) and then improve the generation of DBPs.

  12. Small Multi-Purpose Research Facility (SMiRF)

    NASA Image and Video Library

    2015-10-15

    NASA Glenn engineer Monica Guzik in the Small Multi-Purpose Research Facility (SMiRF). The facility provides the ability to simulate the environmental conditions encountered in space for a variety of cryogenic applications such as thermal protection systems, fluid transfer operations and propellant level gauging. SMiRF is a low-cost, small-scale screening facility for concept and component testing of a wide variety of hardware and is capable of testing cryogenic hydrogen, oxygen, methane and nitrogen.

  13. Comparison of conventional and plant-extract disinfectant solutions on the hardness and color stability of a maxillofacial elastomer after artificial aging.

    PubMed

    Guiotti, Aimée Maria; Goiato, Marcelo Coelho; Dos Santos, Daniela Micheline; Vechiato-Filho, Aljomar José; Cunha, Bruno Guandalini; Paulini, Marcela Borghi; Moreno, Amália; de Almeida, Margarete Teresa Gottardo

    2016-04-01

    Silicone elastomers undergo physical and chemical degradation with disinfecting solutions. Phytotherapy may be a suitable solution for disinfection. However, its effect on the properties of the silicone material is unknown. The purpose of this in vitro study was to evaluate the effect of disinfection with conventional and plant-extract solutions and of artificial aging on the hardness and color stability of a facial silicone associated with pigments and an opacifier. Four hundred specimens of silicone (MDX4-4210) were fabricated (5×6 mm). Two pigment shades and 1 dry opacifier were combined in the tested material, and 4 groups (n=10) were obtained: colorless (GI), colorless with opacifier (GII), medium pigment with opacifier (GIII), and black pigment with opacifier (GIV). Specimens were subjected to disinfection (30 days) using saline solution, water, and neutral soap (digital friction, 30 seconds), chlorhexidine 4%, Hydrastis canadensis, and Cymbopogon nardus extracts (immersion, 10 minutes). Shore A hardness (ASTM D2240) and color analyses were performed before and after disinfection. Specimens were then exposed to 1008 hours of artificial aging (ASTM 53) and subjected to final hardness and color readings. The results were analyzed with ANOVA and the Tukey significant difference test (α=.05). The opacifier increased the hardness (GII). For GII, the H. canadensis solution and the friction with water and soap promoted significantly reduced hardness; the friction also promoted a reduction in this property for GIV. The GIII was not affected after disinfection. A significant difference was found between the ΔE values of the specimens disinfected with H. canadensis, C. nardus, and chlorhexidine, and specimens subjected to saline solution and neutral soap. The hardness of MDX4-4210 after the experimental procedure was considered clinically acceptable for facial prostheses. All groups showed clinically unacceptable color alterations regardless of the disinfecting

  14. The Multi-Purpose Detector (MPD) of the collider experiment

    NASA Astrophysics Data System (ADS)

    Golovatyuk, V.; Kekelidze, V.; Kolesnikov, V.; Rogachevsky, O.; Sorin, A.

    2016-08-01

    The project NICA (Nuclotron-based Ion Collider fAcility) is aimed to study dense baryonic matter in heavy-ion collisions in the energy range up to √{s_{NN}} = 11 GeV with average luminosity of L = 1027 cm-2s-1 (for 197Au79). The experimental program at the NICA collider will be performed with the Multi-Purpose Detector (MPD). We report on the main physics objectives of the NICA heavy-ion program and present the main detector components.

  15. [Disinfection of water: on the need for analysis and solution of fundamental and applied problems].

    PubMed

    Mokienko, A V

    2014-01-01

    In the paper there is presented an analysis of hygienic--medical and environmental aspects of water disinfection as exemplified of chlorine and chlorine dioxide (CD). The concept of persistent multivariate risk for aquatic pathogens, the own vision of the mechanism of formation of chlorine resistance of bacteria under the influence of biocides based on a two-step process of information and spatial interaction of the receptor and the substrate, the hypothesis of hormetic stimulating effect of residual active chlorine (in the complex with other factors) on the growth of aquatic pathogens have been proposed. The aggravation of the significance of halogen containing compounds (HCC) as byproducts of water chlorination in terms of their potential danger as toxicants and carcinogens has been substantiated. Analysis of hygienic and medical and environmental aspects of the use of chlorine dioxide as a means of disinfection of water allowed to justify chemism of its biocidal effect and mechanisms of bactericidal, virucidal, protozoocidal, sporicidal, algacidal actions, removal of biofilms, formation of disinfection byproducts. Chlorine dioxide was shown both to provide epidemic safety of drinking water due to its high virucidal, bactericidal and mycocidal action and to be toxicologically harmless in the context of the influence on the organism of laboratory animals as well as in relation to aquatic organisms under the discharge of disinfected wastewater. There has proved the necessity of the close relationship of fundamental and applied research in performing the first in terms of depth study of microbiological, molecular genetic and epidemiological problems of disinfection (chlorination) of water and the implementation of the latters by means of the introduction of alternative, including combined, technologies for water treatment and disinfection.

  16. System Engineering Strategy for Distributed Multi-Purpose Simulation Architectures

    NASA Technical Reports Server (NTRS)

    Bhula, Dlilpkumar; Kurt, Cindy Marie; Luty, Roger

    2007-01-01

    This paper describes the system engineering approach used to develop distributed multi-purpose simulations. The multi-purpose simulation architecture focuses on user needs, operations, flexibility, cost and maintenance. This approach was used to develop an International Space Station (ISS) simulator, which is called the International Space Station Integrated Simulation (ISIS)1. The ISIS runs unmodified ISS flight software, system models, and the astronaut command and control interface in an open system design that allows for rapid integration of multiple ISS models. The initial intent of ISIS was to provide a distributed system that allows access to ISS flight software and models for the creation, test, and validation of crew and ground controller procedures. This capability reduces the cost and scheduling issues associated with utilizing standalone simulators in fixed locations, and facilitates discovering unknowns and errors earlier in the development lifecycle. Since its inception, the flexible architecture of the ISIS has allowed its purpose to evolve to include ground operator system and display training, flight software modification testing, and as a realistic test bed for Exploration automation technology research and development.

  17. Flow characteristics of Korea multi-purpose research reactor

    SciTech Connect

    Heonil Kim; Hee Taek Chae; Byung Jin Jun; Ji Bok Lee

    1995-09-01

    The construction of Korea Multi-purpose Research Reactor (KMRR), a 30 MW{sub th} open-tank-in-pool type, is completed. Various thermal-hydraulic experiments have been conducted to verify the design characteristics of the KMRR. This paper describes the commissioning experiments to determine the flow distribution of KMRR core and the flow characteristics inside the chimney which stands on top of the core. The core flow is distributed to within {+-}6% of the average values, which is sufficiently flat in the sense that the design velocity in the fueled region is satisfied. The role of core bypass flow to confine the activated core coolant in the chimney structure is confirmed.

  18. Multi-purpose canister system evaluation: A systems engineering approach

    SciTech Connect

    1994-09-01

    This report summarizes Department of Energy (DOE) efforts to investigate various container systems for handling, transporting, storing, and disposing of spent nuclear fuel (SNF) assemblies in the Civilian Radioactive Waste Management System (CRWMS). The primary goal of DOE`s investigations was to select a container technology that could handle the vast majority of commercial SNF at a reasonable cost, while ensuring the safety of the public and protecting the environment. Several alternative cask and canister concepts were evaluated for SNF assembly packaging to determine the most suitable concept. Of these alternatives, the multi-purpose canister (MPC) system was determined to be the most suitable. Based on the results of these evaluations, the decision was made to proceed with design and certification of the MPC system. A decision to fabricate and deploy MPCs will be made after further studies and preparation of an environmental impact statement.

  19. Development of multi-purpose catheter for visceral arteriography.

    PubMed

    Yashiro, N; Kokubo, T; Kawauchi, N; Iio, M

    1989-01-01

    We developed a multi-purpose catheter for visceral arteriography. The outer diameter of the catheter is 5 Fr and the inner diameter admits a 3 Fr catheter. The catheter is made of soft nylon, with a shaft enforced with stainless wire mesh to improve torque transmission. The head is shaped into a three-dimensional configuration, enabling the superselective catheterization that is required for interventional technique as well as arteriography of first-order branches of the abdominal aorta, e.g. the celiac artery and superior mesenteric artery. Using the catheter, we performed 275 arteriographies in 100 cases (first-order-branch arteriography in 190; superselective technique in 85). Arteriography of first-order branches was successful in all cases. The superselective technique was successful without using any other catheters in 89% of cases.

  20. Core-shell silver nanoparticles in endodontic disinfection solutions enable long-term antimicrobial effect on oral biofilms.

    PubMed

    Ertem Bekdemir, Elif; Gutt, Beatrice; Zuber, Flavia; Allegri, Sergio; Le Ouay, Benjamin; Mefti, Selma; Formentin, Kitty; Stellacci, Francesco; Ren, Qun

    2017-09-18

    To achieve effective long-term disinfection of the root canals, we synthesized core-shell silver nanoparticles (AgNPs@SiO2) and used them to develop two irrigation solutions containing sodium phytate (SP) and ethylene glycol-bis(β-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), respectively. Ex vivo studies with instrumented root canals revealed that the developed irrigation solutions can effectively remove the smear layer from the dentinal surfaces. Further in vitro experiments with single and multi-species biofilms demonstrated for the first time that AgNPs@SiO2 based irrigation solutions possess excellent antimicrobial activities for at least 7 days, whereas the bare AgNPs lose the activity almost immediately and do not show any antibacterial activity after 2 days. The long term antimicrobial activity exhibited by AgNPs@SiO2 solutions can be attributed to the sustainable availability of soluble silver, even after 7 days. Both solutions showed lower cytotoxicity towards human gingival fibroblasts compared to the conventionally used solution (3% NaOCl and 17% EDTA). Irrigation solutions containing AgNP@SiO2 may therefore be highly promising for applications needed long-term antimicrobial effect.

  1. Bacterial contamination of stock solutions in storage cases for contact lens, and the disinfectant-resistance of isolates.

    PubMed

    Furuhata, Katsunori; Ishizaki, Naoto; Kawakami, Yasushi; Fukuyama, Masafumi

    2010-09-01

    To investigate the bacterial contamination of preservative solutions for contact lenses, contact lens cases were swabbed and the swabs were cultured. Various bacteria were isolated from 26 of 100 samples (26.0%). By preservative solution, the bacterial presence was low (16.7%) in the 30 samples from cases using ReNu, which was the most frequently employed solution, and 27.3% in 11 samples from cases using Complete, which was the second most frequently employed solution. Of 34 strains isolated and identified, gram-negative bacilli-glucose non-fermenting bacteria were the most frequently isolated, accounting for 61.8% (21 strains); particularly, 10 isolates were Stenotrophomonas maltophilia, accounting for 29.4%. The biofilm-forming ability of these isolates was investigated by staining. The mean absorbance of the gram-negative rods was 0.369, which was about 3 times higher than that (0.107) of the Staphylococcus group, confirming marked biofilm-forming ability. In addition, the bactericidal effects of the preservative solutions on the isolates were investigated. The effect varied among the preservative solutions in the suspension experiment, but the highest disinfection rate, which was achieved by Complete, was 99.9->99.99%, showing a favorable bactericidal effect. In contrast, none of the 3 test preservative solutions showed any bactericidal effect in the adhesion experiment.

  2. Multi-purpose hydrogen isotopes separation plant design

    SciTech Connect

    Boniface, H.A.; Gnanapragasam, N.V.; Ryland, D.K.; Suppiah, S.; Castillo, I.

    2015-03-15

    There is a potential interest at AECL's Chalk River Laboratories to remove tritium from moderately tritiated light water and to reclaim tritiated, downgraded heavy water. With only a few limitations, a single CECE (Combined Electrolysis and Catalytic Exchange) process configuration can be designed to remove tritium from heavy water or light water and upgrade heavy water. Such a design would have some restrictions on the nature of the feed-stock and tritium product, but could produce essentially tritium-free light or heavy water that is chemically pure. The extracted tritium is produced as a small quantity of tritiated heavy water. The overall plant capacity is fixed by the total amount of electrolysis and volume of catalyst. In this proposal, with 60 kA of electrolysis a throughput of 15 kg*h{sup -1} light water for detritiation, about 4 kg*h{sup -1} of heavy water for detritiation and about 27 kg*h{sup -1} of 98% heavy water for upgrading can be processed. Such a plant requires about 1,000 liters of AECL isotope exchange catalyst. The general design features and details of this multi-purpose CECE process are described in this paper, based on some practical choices of design criteria. In addition, we outline the small differences that must be accommodated and some compromises that must be made to make the plant capable of such flexible operation. (authors)

  3. STS-102 Onboard Photograph-Multi-Purpose Logistics Module, Leonardo

    NASA Technical Reports Server (NTRS)

    2001-01-01

    A crewmember of Expedition One, cosmonaut Yuri P. Gidzenko, is dwarfed by transient hardware aboard Leonardo, the Italian Space Agency-built Multi-Purpose Logistics Module (MPLM), a primary cargo of the STS-102 mission. The Leonardo MPLM is the first of three such pressurized modules that will serve as the International Space Station's (ISS's) moving vans, carrying laboratory racks filled with equipment, experiments and supplies to and from the Space Station aboard the Space Shuttle. The cylindrical module is approximately 21-feet long and 15- feet in diameter, weighing almost 4.5 tons. It can carry up to 10 tons of cargo into 16 standard Space Station equipment racks. Of the 16 racks the module can carry, 5 can be furnished with power, data, and fluid to support refrigerators or freezers. In order to function as an attached station module as well as a cargo transport, the logistics module also includes components that provide life support, fire detection and suppression, electrical distribution, and computer functions. The eighth Shuttle mission to visit the ISS, the STS-102 mission served as a crew rotation flight. It delivered the Expedition Two crew to the Station and returned the Expedition One crew back to Earth.

  4. A Multi-purpose Brain-Computer Interface Output Device

    PubMed Central

    Thompson, David E; Huggins, Jane E

    2012-01-01

    While brain-computer interfaces (BCIs) are a promising alternative access pathway for individuals with severe motor impairments, many BCI systems are designed as standalone communication and control systems, rather than as interfaces to existing systems built for these purposes. While an individual communication and control system may be powerful or flexible, no single system can compete with the variety of options available in the commercial assistive technology (AT) market. BCIs could instead be used as an interface to these existing AT devices and products, which are designed for improving access and agency of people with disabilities and are highly configurable to individual user needs. However, interfacing with each AT device and program requires significant time and effort on the part of researchers and clinicians. This work presents the Multi-Purpose BCI Output Device (MBOD), a tool to help researchers and clinicians provide BCI control of many forms of AT in a plug-and-play fashion, i.e. without the installation of drivers or software on the AT device, and a proof-of-concept of the practicality of such an approach. The MBOD was designed to meet the goals of target device compatibility, BCI input device compatibility, convenience, and intuitive command structure. The MBOD was successfully used to interface a BCI with multiple AT devices (including two wheelchair seating systems), as well as computers running Windows (XP and 7), Mac and Ubuntu Linux operating systems. PMID:22208120

  5. Design and performance of multi-purpose vacuum solar collector

    NASA Astrophysics Data System (ADS)

    Balotaki, H. Kavoosi; Saidi, M. H.

    2017-03-01

    Design and fabrication of solar collectors with high performance of energy efficiency to convert solar energy to utility energy is vitally important. This article reports the results obtained from design, construction and investigation of the performance of a Combined Multi-Purpose Vacuum Solar Collector (CMPVSC). This collector consists of three sections: the vacuum section, the liquid section and the air section. In the present collector, it is capable of transferring heat to two flows (liquid and air) simultaneously and separate with the possibility of multipurpose applications. The CMPVSC is compared with the existing individual collectors and the effects of different parameters on the efficiency of this collector are examined. Experimental data indicate that high temperature and high performance with a 43% reduction in cost can be obtained using CMPVSC compared to two individual collectors. To increase the efficiency of the collector, triangular and rectangular channels in the air section have been used. The vacuum part is implemented to reduce heat losses. The effect of water inlet temperature, air flow rate, shape of air channel and vacuum part on the heat delivery by air and water have been investigated. Furthermore, as a matter of comparison of CMPVSC with the individual collector, there is a chance of obtaining highest temperature and efficiency with minimum cost and space requirements.

  6. Design and performance of multi-purpose vacuum solar collector

    NASA Astrophysics Data System (ADS)

    Balotaki, H. Kavoosi; Saidi, M. H.

    2017-09-01

    Design and fabrication of solar collectors with high performance of energy efficiency to convert solar energy to utility energy is vitally important. This article reports the results obtained from design, construction and investigation of the performance of a Combined Multi-Purpose Vacuum Solar Collector (CMPVSC). This collector consists of three sections: the vacuum section, the liquid section and the air section. In the present collector, it is capable of transferring heat to two flows (liquid and air) simultaneously and separate with the possibility of multipurpose applications. The CMPVSC is compared with the existing individual collectors and the effects of different parameters on the efficiency of this collector are examined. Experimental data indicate that high temperature and high performance with a 43% reduction in cost can be obtained using CMPVSC compared to two individual collectors. To increase the efficiency of the collector, triangular and rectangular channels in the air section have been used. The vacuum part is implemented to reduce heat losses. The effect of water inlet temperature, air flow rate, shape of air channel and vacuum part on the heat delivery by air and water have been investigated. Furthermore, as a matter of comparison of CMPVSC with the individual collector, there is a chance of obtaining highest temperature and efficiency with minimum cost and space requirements.

  7. STS-102 Onboard Photograph-Multi-Purpose Logistics Module, Leonardo

    NASA Technical Reports Server (NTRS)

    2001-01-01

    A crewmember of Expedition One, cosmonaut Yuri P. Gidzenko, is dwarfed by transient hardware aboard Leonardo, the Italian Space Agency-built Multi-Purpose Logistics Module (MPLM), a primary cargo of the STS-102 mission. The Leonardo MPLM is the first of three such pressurized modules that will serve as the International Space Station's (ISS's) moving vans, carrying laboratory racks filled with equipment, experiments and supplies to and from the Space Station aboard the Space Shuttle. The cylindrical module is approximately 21-feet long and 15- feet in diameter, weighing almost 4.5 tons. It can carry up to 10 tons of cargo into 16 standard Space Station equipment racks. Of the 16 racks the module can carry, 5 can be furnished with power, data, and fluid to support refrigerators or freezers. In order to function as an attached station module as well as a cargo transport, the logistics module also includes components that provide life support, fire detection and suppression, electrical distribution, and computer functions. The eighth Shuttle mission to visit the ISS, the STS-102 mission served as a crew rotation flight. It delivered the Expedition Two crew to the Station and returned the Expedition One crew back to Earth.

  8. Viability of Acanthamoeba after exposure to a multipurpose disinfecting contact lens solution and two hydrogen peroxide systems

    PubMed Central

    Hiti, K; Walochnik, J; Haller-Schober, E M; Faschinger, C; Aspöck, H

    2002-01-01

    Background/aim: Contact lens cases contaminated with Acanthamoeba are a major risk factor for an infection of the eye. In this study the anti-Acanthamoeba activity of three different contact lens storage solutions was tested. Methods: A new multipurpose contact lens storage solution (Meni Care Plus) and a two step (Titmus H2O2) and one step (Oxysept Comfort) hydrogen peroxide system were tested for their effects on trophozoites and cysts of three different Acanthamoeba species: A castellanii, A hatchetti, and A lenticulata. Results: After a soaking time of 8 hours (overnight soaking of contact lenses) the Titmus H2O2 0.6% solution showed very good amoebicidal effects, while Oxysept Comfort 3% H2O2 could not effectively destroy the cysts of any of the three tested species. Viable cysts of the species A lenticulata and A hatchetti were still present after exposure to Meni Care Plus (0.0005% PHMB) for 8 hours. Conclusion: Not all of the three tested contact lens storage solutions have sufficient amoebicidal effects. The two step peroxide system Titmus H2O2 is a very effective disinfectant contact lens solution in order to avoid a possible Acanthamoeba infection of the eye. PMID:11815336

  9. Safety Assessment of Multi Purpose Small Payload Rack(MSPR)

    NASA Astrophysics Data System (ADS)

    Mizutani, Yoshinobu; Takada, Satomi; Murata, Kosei; Ozawa, Daisaku; Kobayashi, Ryoji; Nakamura, Yasuhiro

    2010-09-01

    We are reporting summary of preliminary safety assessment for Multi Purpose Small Payload Rack(MSPR), which is one of the micro gravity experiment facilities that are being developed for the 2nd phase JEM utilization(JEM: Japanese Experiment Module) that will be launched on H-II Transfer Vehicle(HTV) 2nd flight in 2011. MSPR is used for multi-purpose micro-g experiment providing experimental spaces and work stations. MSPR has three experimental spaces; first, there is a space called Work Volume(WV) with capacity volume of approximately 350 litters, in which multiple resources including electricity, communication, and moving image functions can be used. Within this space, installation of devices can be done by simple, prompt attachment by Velcro and pins with high degree of flexibility. Second, there is Small Experiment Area(SEA), with capacity volume of approximately 70 litters, in which electricity, communication, and moving image functions can also be used in the same way as WV. These spaces protect experiment devices and specimens from contingent loads by the crewmembers. Third, there is Work Bench with area of 0.5 square meters, on which can be used for maintenance, inspection and data operations of installed devices, etc. This bench can be stored in the rack during contingency. Chamber for Combustion Experiment(CCE) that is planned to be installed in WV is a pressure-resistant experimental container that can be used to seal hazardous materials from combustion experiments. This CCE has double sealing design in chamber itself, which resist gas leakage under normal the temperature and pressure. Electricity, communication, moving image function can be used in the same way as WV. JAXA Phase 2 Safety Review Panel(SRP) has been held in April, 2010. For safety analysis of MSPR, hazards were identified based on Fault Tree Analysis methodology and then these hazards were classified into either eight ISS standard-type hazards or eight unique-type hazards that requires

  10. Multi-Purpose Reefs - A Decade of Application

    NASA Astrophysics Data System (ADS)

    Mead, S.; Borrero, J. C.; Hearin, J.

    2011-12-01

    Offshore submerged structures for coastal protection and artificial reefs for enhancing local marine biodiversity and/or attracting sea life have been utilized for centuries. Indeed, the first known use of artificial reef structures for habitat enhancement dates back to 2000 BC on the south west coast of India. However, it was not until the 1960's that multi- purpose reefs (MPRs) intended combine coastal protection, eco-enhancement and surfing were first proposed. Through the 1970's and 1980's the concept of MPR's was advanced through the seminal works of James 'Kimo' Walker who pioneered the area of surfing science and developed the first methods for quantification of a surfing break. Design studies for artificial reefs primarily for surfing were undertaken for the construction of the world's first artificial surfing reef built in Perth in 1998, as well as for artificial reefs in California and the Queensland Gold Coast MPR in Australia. More than a decade on, seven reefs have now been constructed at locations around the world with differing levels of success. and a great deal has been learned about the functionality of and potential applications for these structures. This poster provides a brief update on the performance of these structures, summarizing the large volume of monitoring data available for many of these projects. This includes data on shoreline protection and beach response, ecological enhancement, habitat restoration and improvement of recreational amenities. We discuss several projects with respect to the above topics as well as some of the lessons learned in the light of future MPR developments. This poster considers the performance of MPR's in three primary areas of functionality: coastal protection, ecological enhancement and surfing enhancement. We also discuss some of the lessons learned and applied as understanding of these structures has increased.

  11. Contamination of toothbrush at different time intervals and effectiveness of various disinfecting solutions in reducing the contamination of toothbrush.

    PubMed

    Sogi, Suma H P; Subbareddy, V V; Kiran, Shashi N D

    2002-09-01

    The common devices used for oral hygiene measures are toothbrush, dentifrice and oral rinses. Present study was carried out to know the level of contamination of toothbrush after brushing and at the same time, to know the efficacy of various disinfecting solution in reducing their contamination. Thirty two children in the age group of 12-14, residing in Government Hostel were selected. They were divided into four groups of 8 each, and were supplied with toothbrushes. Toothbrushes were cultured to assess the contamination at different time intervals. Control group had shown the highest percentage of contamination. It was concluded that cleaning of the oral cavity is not the only procedure in maintaining the oral hygiene, the oral hygiene devices should also be kept clean.

  12. Effect of immersion disinfection of alginate impressions in sodium hypochlorite solution on the dimensional changes of stone models.

    PubMed

    Hiraguchi, Hisako; Kaketani, Masahiro; Hirose, Hideharu; Yoneyama, Takayuki

    2012-01-01

    This study investigated the effect of the immersion of alginate impressions in 0.5% sodium hypochlorite solution for 15 min on the dimensional changes of stone models designed to simulate a sectional form of a residual ridge. Five brands of alginate impression materials, which underwent various dimensional changes in water, were used. A stone model made with an impression that had not been immersed was prepared as a control. The immersion of two brands of alginate impressions that underwent small dimensional changes in water did not lead to serious deformation of the stone models, and the differences in the dimensional changes between the stone models produced with disinfected impressions and those of the control were less than 15 µm. In contrast, the immersions of three brands of alginate impressions that underwent comparatively large dimensional changes in water caused deformation of the stone models.

  13. Effects of different irrigating solutions and disinfection methods on push-out bond strengths of fiber posts.

    PubMed

    Ertas, Huseyin; Ok, Evren; Uysal, Banu; Arslan, Hakan

    2014-11-01

    The aim of this study was to evaluate the effects of various irrigating solutions and photoactivated disinfection (PAD) on the push-out bond strengths of fiber posts to root dentin. Thirty-two human teeth were divided into eight groups, as follows: (1) irrigation with physiologic saline (control), (2) NaOCl irrigation, (3) chlorhexidine (CHX) irrigation, (4) ethanol (EtOH) irrigation, (5) NaOCl followed by 17% EDTA irrigation, (6) NaOCl-EDTA supplemented with CHX irrigation, (7) NaOCl-EDTA supplemented with EtOH irrigation and (8) NaOCl-EDTA irrigation supplemented with PAD. After the posts were cemented, the roots were transversally sectioned to obtain four slices (1 mm thick) (n = 16). Push-out tests were conducted by applying a load at 0.5 mm/min, types of fracture failures were recorded and data were analyzed with one-way ANOVA and Tukey post-hoc tests (p = 0.05). Push-out bond strength was significantly affected by the type of irrigating solution and the disinfection protocol (p < 0.05). The bond strength of the EtOH, NaOCl and NaOCl-EDTA-CHX irrigated groups was significantly higher than that of the other groups. The highest bond strength was observed in the EtOH irrigated group and the lowest was the NaOCl-EDTA irrigated group. Irrigation with NaOCl and EDTA combined caused lower bond strength than observed in the control group. However, supplementing this combination with CHX improved the post-dentin bond strengths; supplementing with PAD did not.

  14. Laboratory bonding ability of a multi-purpose dentin adhesive.

    PubMed

    Perdigão, Jorge; Sezinando, Ana; Monteiro, Paulo C

    2012-06-01

    To evaluate the laboratory dentin and enamel microtensile bond strengths (microTBS) and interfacial ultra-morphology of a new multi-purpose dental adhesive applied under different bonding strategies. microTBS - 36 extracted caries-free human molars were assigned to six groups: Group CSE - Clearfil SE Bond, a 2-step self-etch adhesive (self-etch control); Group SBU-SE - Scotchbond Universal Adhesive (SBU), applied as a one-step self-etch adhesive; Group OSLm - OptiBond SOLO Plus (OSL), a 2-step etch-and-rinse adhesive applied on moist dentin (etch-and-rinse control); Group OSLd - OSL applied on air-dried dentin; Group SBU-ERm - SBU applied as a 2-step etch-and-rinse adhesive on moist dentin; Group SBU-ERd - SBU applied as a 2-step etch-and-rinse adhesive on air-dried dentin. Build-ups were constructed with Filtek Z250 and cured in three increments of 2 mm each. Specimens were sectioned with a slow-speed diamond saw under water in X and Y directions to obtain bonded beams that were tested to failure in tension at a crosshead speed of 1 mm/minute. Statistical analyses were computed using one-way ANOVA followed by post-hoc tests at P< 0.05. Ultra-morphologic evaluation - dentin-resin interfaces were prepared for each of the six groups, processed, and observed under a FESEM. microTBS - OSLm resulted in significantly higher mean microTBS (63.0 MPa) than the other five groups. All SBU groups ranked in the same statistical subset regardless of the dentin treatment. The lowest mean microTBS were obtained with CSE (47.2 MPa) and OSLd (50.2 MPa), which were ranked in the same statistical subset. Ultramorphologic evaluation - The two self-etch adhesives resulted in a similar ultra-morphology. Dried dentin did not preclude the formation of a hybrid layer with SBU-ERd, as opposed to OSLd.

  15. 9 CFR 91.41 - Cleaning and disinfecting of aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... animals on the aircraft shall be cleaned and disinfected using an approved disinfectant listed in § 71.10... stowage area. The disinfectant solution must be applied with a device that creates an aerosol or mist that...

  16. 9 CFR 91.41 - Cleaning and disinfecting of aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... animals on the aircraft shall be cleaned and disinfected using an approved disinfectant listed in § 71.10... stowage area. The disinfectant solution must be applied with a device that creates an aerosol or mist that...

  17. 9 CFR 91.41 - Cleaning and disinfecting of aircraft.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... animals on the aircraft shall be cleaned and disinfected using an approved disinfectant listed in § 71.10... stowage area. The disinfectant solution must be applied with a device that creates an aerosol or mist that...

  18. 9 CFR 91.41 - Cleaning and disinfecting of aircraft.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... animals on the aircraft shall be cleaned and disinfected using an approved disinfectant listed in § 71.10... stowage area. The disinfectant solution must be applied with a device that creates an aerosol or mist that...

  19. Mycobacterium massiliense BRA100 strain recovered from postsurgical infections: resistance to high concentrations of glutaraldehyde and alternative solutions for high level disinfection.

    PubMed

    Lorena, Nádia Suely de Oliveira; Pitombo, Marcos Bettini; Côrtes, Patrícia Barbur; Maya, Maria Cristina Araújo; Silva, Marlei Gomes da; Carvalho, Ana Carolina da Silva; Coelho, Fábrice Santana; Miyazaki, Neide Hiromi Tokumaru; Marques, Elizabeth Andrade; Chebabo, Alberto; Freitas, Andréa D'Avila; Lupi, Otília; Duarte, Rafael Silva

    2010-10-01

    To evaluate the minimum inhibitory concentration (MIC) of GTA against these microorganisms and alternative disinfectants for high-level disinfection (HLD). Reference mycobacteria and clinical M. massiliense strains were included in this study. Active cultures were submitted to susceptibility qualitative tests with GTA dilutions (ranging from 1.5% to 8%), and commercial orthophthaldehyde (OPA) and peracetic acid (PA)-based solutions, during the period of exposure as recommended by National Agency of Sanitary Surveillance for HLD. All reference and M. massiliense non-BRA100 strains, recovered from sputum, were susceptible to any GTA concentration, OPA and PA solutions. M. massiliense BRA100 strains presented MIC of 8% GTA and were susceptible to OPA and PA. M. massiliense BRA100 strain is resistant to high GTA concentrations (up to 7%), which proves that this product is non-effective against specific rapidly growing mycobacteria and should be substituted by OPA or PA-based solutions for HLD.

  20. 16 CFR 1212.3 - Requirements for multi-purpose lighters.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Requirements for multi-purpose lighters. 1212.3 Section 1212.3 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS SAFETY STANDARD FOR MULTI-PURPOSE LIGHTERS Requirements for Child-Resistance §...

  1. 16 CFR 1212.3 - Requirements for multi-purpose lighters.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Requirements for multi-purpose lighters. 1212.3 Section 1212.3 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS SAFETY STANDARD FOR MULTI-PURPOSE LIGHTERS Requirements for Child-Resistance §...

  2. 16 CFR 1212.3 - Requirements for multi-purpose lighters.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Requirements for multi-purpose lighters. 1212.3 Section 1212.3 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS SAFETY STANDARD FOR MULTI-PURPOSE LIGHTERS Requirements for Child-Resistance §...

  3. 9 CFR 96.14 - Uncertified casings; disinfection with saturated brine solution.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... acid as at present or if preferred may be submerged in a saturated brine solution at a temperature not less than 127 °F. for at least 15 minutes. The time held as well as the temperature of such brine solution must be recorded on a one-hour dial of a recording thermometer and filed in the local APHIS office...

  4. 9 CFR 96.14 - Uncertified casings; disinfection with saturated brine solution.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... acid as at present or if preferred may be submerged in a saturated brine solution at a temperature not less than 127 °F. for at least 15 minutes. The time held as well as the temperature of such brine solution must be recorded on a one-hour dial of a recording thermometer and filed in the local APHIS office...

  5. A new NASA LaRC Multi-Purpose Prepregging Unit

    NASA Technical Reports Server (NTRS)

    Wilkinson, S. P.; Marchello, J. M.; Dixon, D.; Johnston, N. J.

    1993-01-01

    A multi-purpose prepregging machine has been designed and built for NASA Langley Research Center. The machine has numerous advantages over existing units due to its various modular components. Each of these can be used individually or simultaneously depending on the required prepregging method. A reverse roll coater provides the ability to prepare thin films from typical hot-melt thermoset formulations. Also, if necessary, the design allows direct fiber impregnation within the reverse roll coater gap. Included in the impregnation module is a solution dip tank allowing the fabrication of thermoplastic prepregs from solution. The proceeding modules within the unit consist of four nip stations, two hot-plates, a hot-sled option and a high temperature oven. This paper describes the advantages of such a modular construction and discusses the various processing combinations available to the prepregger. A variety of high performance prepreg material systems were produced on IM7 (Hercules) carbon fiber. These included LaRC RP46, a PMR-type resin processed from methanol and two polyamide acids, LaRC IA and LaRC ITPI, prpregged from N-methyl pyrrolidinone (NMP). Parameters involved in the production of these prepreg materials are presented as are the mechanical properties of the resulting good quality laminates. A brief introduction into the existing prepregging science is presented. Topics relating to solution prepregging are identified with a focus on the current research effort and its future development.

  6. [The role of bacterial contamination of milking utensils and disinfecting solutions as a possible cause of clinical mastitis in dairy cows].

    PubMed

    Hässig, M; Sigrist, S M; Corti, S; Giezendanner, N; Stephan, R

    2011-06-01

    Various instruments and utensils used during milking as well as teat dip solutions were examined for contamination with coagulase-negative staphylococci (CNS). The goal of this study was to investigate the relationship between contaminated fomites and udder infection in dairy cows. A total of 344 cows from ten dairy farms with the highest rate of clinical mastitis among the farms serviced by the Ambulatory Clinic of the University of Zurich were included in the study. Each farm was visited five times. All lactating cows, with the exception of those undergoing antibiotic treatment, were examined immediately before milking using the California Mastitis Test (CMT). A milk sample was collected from positive quarters. Items used to clean the udder, which included wood wool, paper towels and disinfecting towels as well as the milker's hands and the teat dip cup were swabbed for bacteriological examination. Water samples, samples of teat dip and cleaning solutions were also collected and cultured. Our results demonstrate that cleaning and disinfecting solutions have the potential to transmit udder pathogens and cause clinical mastitis. The most common CNS isolated from quarter samples were S. saprophyticus, S. sciuri and S. chromogenes, and the most common CNS isolated from utensils, cleaning and disinfecting solutions were S. fleuretii, S. vitulus, S. equorum, S. sciuri, S. haemolyticus, S. succinus and S. saprophyticus.

  7. Stability of antimicrobial activity of peracetic acid solutions used in the final disinfection process.

    PubMed

    Costa, Solange Alves da Silva; Paula, Olívia Ferreira Pereira de; Silva, Célia Regina Gonçalves E; Leão, Mariella Vieira Pereira; Santos, Silvana Soléo Ferreira dos

    2015-01-01

    The instruments and materials used in health establishments are frequently exposed to microorganism contamination, and chemical products are used before sterilization to reduce occupational infection. We evaluated the antimicrobial effectiveness, physical stability, and corrosiveness of two commercial formulations of peracetic acid on experimentally contaminated specimens. Stainless steel specimens were contaminated with Staphylococcus aureus, Escherichia coli, Candida albicans, blood, and saliva and then immersed in a ready peracetic acid solution: 2% Sekusept Aktiv (SA) or 0.25% Proxitane Alpha (PA), for different times. Then, washes of these instruments were plated in culture medium and colony-forming units counted. This procedure was repeated six times per day over 24 non-consecutive days. The corrosion capacity was assessed with the mass loss test, and the concentration of peracetic acid and pH of the solutions were measured with indicator tapes. Both SA and PA significantly eliminated microorganisms; however, the SA solution was stable for only 4 days, whereas PA remained stable throughout the experiment. The concentration of peracetic acid in the SA solutions decreased over time until the chemical was undetectable, although the pH remained at 5. The PA solution had a concentration of 500-400 mg/L and a pH of 2-3. Neither formulation induced corrosion and both reduced the number of microorganisms (p = 0.0001). However, the differences observed in the performance of each product highlight the necessity of establishing a protocol for optimizing the use of each one.

  8. [The microorganism count on impressions after their disinfection by submersion in sodium hypochlorite solutions].

    PubMed

    Koshmanova, T N; Panteleeva, L G

    1998-01-01

    The virucidal, bactericidal, and fungicidal activity of sodium hypochlorite is studied with silicone imprints. Poliomyelitis virus (type I vaccine strain Sabin LSc 2 ab with titer 10(7.36) TCD50/ml), bacteriophage f52 with titer 2.10(7) PFU/ml, Staphylococcus aureus strain 906, and Candida albicans in concentrations 10(7) corpuscles/ml in the presence of protein die completely in 20 min when submerged in 0.5% sodium hypochlorite solution. Imprints from alginate materials are destroyed if submerged in this solution.

  9. Orion Multi-Purpose Crew Vehicle Solving and Mitigating the Two Main Cluster Pendulum Problem

    NASA Technical Reports Server (NTRS)

    Ali, Yasmin; Sommer, Bruce; Troung, Tuan; Anderson, Brian; Madsen, Christopher

    2017-01-01

    The Orion Multi-purpose Crew Vehicle (MPCV) Orion spacecraft will return humans from beyond earth's orbit, including Mars and will be required to land 20,000 pounds of mass safely in the ocean. The parachute system nominally lands under 3 main parachutes, but the system is designed to be fault tolerant and land under 2 main parachutes. During several of the parachute development tests, it was observed that a pendulum, or swinging, motion could develop while the Crew Module (CM) was descending under two parachutes. This pendulum effect had not been previously predicted by modeling. Landing impact analysis showed that the landing loads would double in some places across the spacecraft. The CM structural design limits would be exceeded upon landing if this pendulum motion were to occur. The Orion descent and landing team was faced with potentially millions of dollars in structural modifications and a severe mass increase. A multidisciplinary team was formed to determine root cause, model the pendulum motion, study alternate canopy planforms and assess alternate operational vehicle controls & operations providing mitigation options resulting in a reliability level deemed safe for human spaceflight. The problem and solution is a balance of risk to a known solution versus a chance to improve the landing performance for the next human-rated spacecraft.

  10. Multi-criteria objective based climate change impact assessment for multi-purpose multi-reservoir systems

    NASA Astrophysics Data System (ADS)

    Müller, Ruben; Schütze, Niels

    2014-05-01

    Water resources systems with reservoirs are expected to be sensitive to climate change. Assessment studies that analyze the impact of climate change on the performance of reservoirs can be divided in two groups: (1) Studies that simulate the operation under projected inflows with the current set of operational rules. Due to non adapted operational rules the future performance of these reservoirs can be underestimated and the impact overestimated. (2) Studies that optimize the operational rules for best adaption of the system to the projected conditions before the assessment of the impact. The latter allows for estimating more realistically future performance and adaption strategies based on new operation rules are available if required. Multi-purpose reservoirs serve various, often conflicting functions. If all functions cannot be served simultaneously at a maximum level, an effective compromise between multiple objectives of the reservoir operation has to be provided. Yet under climate change the historically preferenced compromise may no longer be the most suitable compromise in the future. Therefore a multi-objective based climate change impact assessment approach for multi-purpose multi-reservoir systems is proposed in the study. Projected inflows are provided in a first step using a physically based rainfall-runoff model. In a second step, a time series model is applied to generate long-term inflow time series. Finally, the long-term inflow series are used as driving variables for a simulation-based multi-objective optimization of the reservoir system in order to derive optimal operation rules. As a result, the adapted Pareto-optimal set of diverse best compromise solutions can be presented to the decision maker in order to assist him in assessing climate change adaption measures with respect to the future performance of the multi-purpose reservoir system. The approach is tested on a multi-purpose multi-reservoir system in a mountainous catchment in Germany. A

  11. Whole body vibration: unsupervised training or combined with a supervised multi-purpose exercise for fitness?

    PubMed

    Emerenziani, Gian Pietro; Meucci, Marco; Gallotta, Maria Chiara; Buzzachera, Cosme Franklim; Guidetti, Laura; Baldari, Carlo

    2014-01-01

    The aim of the study was to compare the effect of an unsupervised whole body vibration (WBV) training and two different supervised multi-purpose exercise programmes, with and without WBV, on body composition, functional fitness and self-reported well-being in middle-aged adults. Fifty-four healthy participants (age 48.6 ± 6.7 years) were randomly assigned to a vibration group (VG), a multi-purpose exercise group (MG) and a multi-purpose exercise with vibration group (VMG) and trained 3 days a week for 4 months. VG performed a standardised unsupervised WBV protocol, MG a supervised multi-purpose exercise and VMG a multi-purpose exercise including vibration. After training, drop out was significantly higher in VG group (P = 0.016) when compared to VMG group. In both MG and VMG, body composition, sit-up, push-up, sit and reach, agility test, hopping test and self-reported general health significantly improved (P < 0.05). No additive effects were generated by the vibration stimulus. Percentage of body fat and agility test in VG had a significant opposite trend compared to VMG group (P < 0.05). In summary, an unsupervised WBV training should not be chosen for training protocol. However, positive effects on physical fitness and the best results in adherence could be achieved integrating WBV practice into a multi-purpose exercise training.

  12. Earthscape, a Multi-Purpose Interactive 3d Globe Viewer for Hybrid Data Visualization and Analysis

    NASA Astrophysics Data System (ADS)

    Sarthou, A.; Mas, S.; Jacquin, M.; Moreno, N.; Salamon, A.

    2015-08-01

    The hybrid visualization and interaction tool EarthScape is presented here. The software is able to display simultaneously LiDAR point clouds, draped videos with moving footprint, volume scientific data (using volume rendering, isosurface and slice plane), raster data such as still satellite images, vector data and 3D models such as buildings or vehicles. The application runs on touch screen devices such as tablets. The software is based on open source libraries, such as OpenSceneGraph, osgEarth and OpenCV, and shader programming is used to implement volume rendering of scientific data. The next goal of EarthScape is to perform data analysis using ENVI Services Engine, a cloud data analysis solution. EarthScape is also designed to be a client of Jagwire which provides multisource geo-referenced video fluxes. When all these components will be included, EarthScape will be a multi-purpose platform that will provide at the same time data analysis, hybrid visualization and complex interactions. The software is available on demand for free at france@exelisvis.com.

  13. Glove resistance to permeation by a 7.5% hydrogen peroxide sterilizing and disinfecting solution.

    PubMed

    Monticello, M V; Gaber, D J

    1999-08-01

    This study evaluated 6 types of glove materials for resistance to permeation by a 7.5% hydrogen peroxide liquid chemical germicide. Based on American Society for Testing and Materials Method F739-96, a small piece of glove material was placed in the center of a dual chamber test cell. The challenge and collection chambers of the test cell were filled with the hydrogen peroxide test chemical and the collecting medium (deionized water), respectively. Chemical permeation was determined by measuring the concentration of hydrogen peroxide in the collection medium at various time intervals. Both the polyvinylchloride and disposable latex examination gloves at 4.5 mil thickness provided less than 30 minutes of protection from hydrogen peroxide. The natural rubber latex glove at 16.5 mil lasted for 8 hours without any detectable penetration. Neoprene (15 mil) and nitrile butyl rubber (18 mil) both provided excellent protection throughout the 8-hour test period. Disposable latex examination gloves should be used for short-term exposure to hydrogen peroxide solutions. Thicker rubber latex gloves provided adequate protection and necessary dexterity for conducting intricate tasks. The level of protection depends largely on the thickness and quality of the glove material.

  14. Silver deposition on stainless steel container surfaces in contact with disinfectant silver aqueous solutions

    NASA Astrophysics Data System (ADS)

    Petala, M.; Tsiridis, V.; Mintsouli, I.; Pliatsikas, N.; Spanos, Th.; Rebeyre, P.; Darakas, E.; Patsalas, P.; Vourlias, G.; Kostoglou, M.; Sotiropoulos, S.; Karapantsios, Th.

    2017-02-01

    Silver is the preservative used on the Russian segment of the International Space Station (ISS) to prevent microbial proliferation within potable water supplies. Yet, in the frame of the European Automated Transfer Vehicle (ATV) missions to ISS, silver depletion from water has been detected during ground transportation of this water to launch site, thereby indicating a degradation of water quality. This study investigates the silver loss from water when in contact with stainless steel surfaces. Experiments are conducted with several types of stainless steel surfaces being exposed to water containing 10 or 0.5 mg/L silver ions. Results show that silver deposits on stainless steel surfaces even when a passivation layer protects the metallic surface. The highest protection to silver deposition is offered by acid passivated and electropolished SS 316L. SEM and XPS experiments were carried out at several locations of the sample area that was in contact with the Ag solution and found similar morphological (SEM) and compositional (sputter-etch XPS) results. The results reveal that silver deposits uniformly across the wetted surface to a thickness larger than 3 nm. Moreover, evidence is provided that silver deposits in its metallic form on all stainless steel surfaces, in line with a galvanic deposition mechanism. Combination of ICP-MS and XPS results suggests a mechanism for Ag deposition/reduction with simultaneous substrate oxidation resulting in oxide growth at the exposed stainless steel surface.

  15. The effect of a surface disinfectant on a dental cast.

    PubMed

    Bass, R A; Plummer, K D; Anderson, E F

    1992-05-01

    This study determined the effect of a disinfectant solution on dental casts. Stone samples were immersed in a disinfectant solution and in control solutions. The results indicate that a saturated calcium sulfate (clear slurry) solution with 0.525% sodium hypochlorite was an effective disinfectant and acted without damage to the dental cast.

  16. Disinfection of contaminated equipment: evaluation of benzalkonium chloride exposure time and solution age and the ability of air-drying to eliminate Flavobacterium psychrophilum.

    PubMed

    Oplinger, Randall W; Wagner, Eric

    2010-12-01

    Disinfection of equipment that comes in contact with fish can help to minimize the spread of Flavobacterium psychrophilum (the etiological agent of bacterial coldwater disease) within and among fish culture facilities. We present the results of three studies that evaluated the potential use of benzalkonium chloride and air-drying to kill surface-attached F. psychrophilum. In the first study, we established a vat with a 600-mg/L benzalkonium chloride solution and sampled this solution 0, 14, 35, 56, 70, and 84 d after creation. The solution was kept outdoors and subjected to typical hatchery use. Plastic test strips were dipped in a solution containing F. psychrophilum and were then immersed in benzalkonium chloride for 0, 1, 10, 30, or 60 min. The strips were then rinsed with sterile water and streaked across a plate containing tryptone yeast extract salts (TYES) medium. No culturable bacteria were detected from any strips immersed for 10, 30, or 60 min. Bacteria were detected on 17% of the strips that were immersed for 1 min. The age of the benzalkonium chloride solution had no effect on disinfection ability. In the second study, plastic strips were immersed in a solution containing F. psychrophilum and then were dipped in a 600-mg/L benzalkonium chloride solution for 10 s. The strips were then air-dried for 1 h and were streaked onto TYES medium. No bacterial growth was observed from any strips in the second experiment. The third study determined whether air-drying alone was sufficient to kill F. psychrophilum. Plastic strips were dipped in a solution containing F. psychrophilum; were allowed to dry at room temperature for 0, 24, 48, or 96 h; and were then streaked across TYES medium. Bacteria were cultured from strips representing each drying interval, indicating that air-drying times of 96 h or less are insufficient to kill F. psychrophilum.

  17. An integrated and multi-purpose microscope for the characterization of atomically thin optoelectronic devices

    NASA Astrophysics Data System (ADS)

    De Sanctis, Adolfo; Jones, Gareth F.; Townsend, Nicola J.; Craciun, Monica F.; Russo, Saverio

    2017-05-01

    Optoelectronic devices based on graphene and other two-dimensional (2D) materials, such as transition metal dichalcogenides (TMDs), are the focus of wide research interest. They can be the key to improving bandwidths in telecommunications, capacity in data storage, and new features in consumer electronics, safety devices, and medical equipment. The characterization of these emerging atomically thin materials and devices strongly relies on a set of measurements involving both optical and electronic instrumentation ranging from scanning photocurrent mapping to Raman and photoluminescence (PL) spectroscopy. Furthermore, proof-of-concept devices are usually fabricated from micro-meter size flakes, requiring microscopy techniques to characterize them. Current state-of-the-art commercial instruments offer the ability to characterize individual properties of these materials with no option for the in situ characterization of a wide enough range of complementary optical and electrical properties. Presently, the requirement to switch atomically thin materials from one system to another often radically affects the properties of these uniquely sensitive materials through atmospheric contamination. Here, we present an integrated, multi-purpose instrument dedicated to the optical and electrical characterization of devices based on 2D materials which is able to perform low frequency electrical measurements, scanning photocurrent mapping, and Raman, absorption, and PL spectroscopy in one single setup with full control over the polarization and wavelength of light. We characterize this apparatus by performing multiple measurements on graphene, transition metal dichalcogenides (TMDs), and Si. The performance and resolution of each individual measurement technique is found to be equivalent to that of commercially available instruments. Contrary to nowadays' commercial systems, a significant advantage of the developed instrument is that for the first time the integration of a wide

  18. An integrated and multi-purpose microscope for the characterization of atomically thin optoelectronic devices.

    PubMed

    De Sanctis, Adolfo; Jones, Gareth F; Townsend, Nicola J; Craciun, Monica F; Russo, Saverio

    2017-05-01

    Optoelectronic devices based on graphene and other two-dimensional (2D) materials, such as transition metal dichalcogenides (TMDs), are the focus of wide research interest. They can be the key to improving bandwidths in telecommunications, capacity in data storage, and new features in consumer electronics, safety devices, and medical equipment. The characterization of these emerging atomically thin materials and devices strongly relies on a set of measurements involving both optical and electronic instrumentation ranging from scanning photocurrent mapping to Raman and photoluminescence (PL) spectroscopy. Furthermore, proof-of-concept devices are usually fabricated from micro-meter size flakes, requiring microscopy techniques to characterize them. Current state-of-the-art commercial instruments offer the ability to characterize individual properties of these materials with no option for the in situ characterization of a wide enough range of complementary optical and electrical properties. Presently, the requirement to switch atomically thin materials from one system to another often radically affects the properties of these uniquely sensitive materials through atmospheric contamination. Here, we present an integrated, multi-purpose instrument dedicated to the optical and electrical characterization of devices based on 2D materials which is able to perform low frequency electrical measurements, scanning photocurrent mapping, and Raman, absorption, and PL spectroscopy in one single setup with full control over the polarization and wavelength of light. We characterize this apparatus by performing multiple measurements on graphene, transition metal dichalcogenides (TMDs), and Si. The performance and resolution of each individual measurement technique is found to be equivalent to that of commercially available instruments. Contrary to nowadays' commercial systems, a significant advantage of the developed instrument is that for the first time the integration of a wide

  19. A membrane filter technique for testing disinfectants.

    PubMed Central

    Prince, J; Deverill, C E; Ayliffe, G A

    1975-01-01

    A membrane filter was used for assessing the surface disinfecting activity of phenolic disinfectants and a chloroxylenol disinfectant. The influence of the type of organism, inoculum size, and hardness of water was investigated. Pseudomonas aeruginosa was chosen for the standardized test. Disinfectant solutions were prepared in water of 300 ppm hardness and applied for two and a half minutes and eight minutes to the bacteria deposited from filtration of 1 ml of a suspension containing 10-6 bacteria. The membrane filter test has certain advantages over many tests, eg, all organisms surviving after treatment can be counted and residual disinfectant is easily removed. PMID:804497

  20. A membrane filter technique for testing disinfectants.

    PubMed

    Prince, J; Deverill, C E; Ayliffe, G A

    1975-01-01

    A membrane filter was used for assessing the surface disinfecting activity of phenolic disinfectants and a chloroxylenol disinfectant. The influence of the type of organism, inoculum size, and hardness of water was investigated. Pseudomonas aeruginosa was chosen for the standardized test. Disinfectant solutions were prepared in water of 300 ppm hardness and applied for two and a half minutes and eight minutes to the bacteria deposited from filtration of 1 ml of a suspension containing 10-6 bacteria. The membrane filter test has certain advantages over many tests, eg, all organisms surviving after treatment can be counted and residual disinfectant is easily removed.

  1. Engineering a Multi-Purpose Test Collection for Web Retrieval Experiments.

    ERIC Educational Resources Information Center

    Bailey, Peter; Craswell, Nick; Hawking, David

    2003-01-01

    Describes a test collection that was developed as a multi-purpose testbed for experiments on the Web in distributed information retrieval, hyperlink algorithms, and conventional ad hoc retrieval. Discusses inter-server connectivity, integrity of server holdings, inclusion of documents related to a wide spread of likely queries, and distribution of…

  2. SPENT NUCLEAR FUEL NUMBER DENSITIES FOR MULTI-PURPOSE CANISTER CRITICALITY CALCULATIONS

    SciTech Connect

    D. A. Thomas

    1996-01-12

    The purpose of this analysis is to calculate the number densities for spent nuclear fuel (SNF) to be used in criticality evaluations of the Multi-Purpose Canister (MPC) waste packages. The objective of this analysis is to provide material number density information which will be referenced by future MPC criticality design analyses, such as for those supporting the Conceptual Design Report.

  3. Disinfecting capabilities of oxychlorine compounds.

    PubMed Central

    Noss, C I; Olivieri, V P

    1985-01-01

    The bacterial virus f2 was inactivated by chlorine dioxide at acidic, neutral, and alkaline pH values. The rate of inactivation increased with increasing pH. Chlorine dioxide disproportionation products, chlorite and chlorate, were not active disinfectants. As chlorine dioxide solutions were degraded under alkaline conditions, they displayed reduced viricidal effectiveness, thereby confirming the chlorine dioxide free radical as the active disinfecting species. PMID:3911893

  4. The Army’s Armored Multi-Purpose Vehicle (AMPV): Background and Issues for Congress

    DTIC Science & Technology

    2016-09-14

    development of an air-transportable, armored multi-purpose vehicle family intended to provide a lightweight, amphibious armored personnel carrier...AMPV) is the proposed United States Army program for replacement of the M-113 Family of Vehicles (FOV) to mitigate current and future capability...Fiscal Year (FY) 2017, February 2016, p. 16. 22 U.S. Army Europe Fact Sheet: “U.S. Army European Activity Set,” http://www.eur.army.mil/jmtc/ exercises

  5. The International Space Station's Multi-Purpose Logistics Module, Thermal Performance of the First Five Flights

    NASA Technical Reports Server (NTRS)

    Holladay, Jon; Cho, Frank

    2003-01-01

    The Multi-Purpose Logistics Module is the primary carrier for transport of pressurized payload to the International Space Station. Performing five missions within a thirteen month span provided a unique opportunity to gather a great deal of information toward understanding and verifying the orbital performance of the vehicle. This paper will provide a brief overview of the hardware history and design capabilities followed by a summary of the missions flown, resource requirements and possibilities for the future.

  6. Explosive Ordnance Disposal Proficiency Range and Multi-Purpose Contingency Training Area

    DTIC Science & Technology

    2007-04-01

    measures, including but not limited to installation of safety fencing, straw bales , silt fence, seeding (temporary and permanent), planting native grasses...point. All combustible materials would be cleared from a 200-foot radius inner circle surrounding the destruction point. • Multi-Purpose Contingency...Chapter 2 April 2007 2-5 entrances, would ring the destruction point. All combustible materials would be cleared from a 200-foot radius inner

  7. Multi-Purpose, Application-Centric, Scalable I/O Proxy Application

    SciTech Connect

    Miller, M. C.

    2015-06-15

    MACSio is a Multi-purpose, Application-Centric, Scalable I/O proxy application. It is designed to support a number of goals with respect to parallel I/O performance testing and benchmarking including the ability to test and compare various I/O libraries and I/O paradigms, to predict scalable performance of real applications and to help identify where improvements in I/O performance can be made within the HPC I/O software stack.

  8. Raffaello Multi-Purpose Logistics Module (MPLM) in the Endeavour payload bay prior to docking

    NASA Image and Video Library

    2001-04-21

    ISS002-E-5815 (21 April 2001) --- The Raffaello Multi-Purpose Logistics Module (MPLM), built by the Italian Space Agency (ASI), sits in its berthed position in the cargo bay of the Space Shuttle Endeavour as the STS-100 crew eases the vehicle close to the International Space Station (ISS) for docking. The image was recorded with a digital still camera by one of the Expedition Two crew members aboard the Station.

  9. Performance test on PELICAN - a multi-purpose time of flight cold neutron spectrometer

    NASA Astrophysics Data System (ADS)

    Yu, Dehong; Mole, Richard. A.; Kearley, Gordon J.

    2015-01-01

    Pelican, a direct geometry multi-purpose cold neutron spectrometer has recently been commissioned at the Bragg Institute, ANSTO. The energy resolution and flux at the sample position as a function of neutron wavelength has been evaluated and time focusing at selected energy transfers has also been demonstrated. Several test experiments of quasi-elastic and inelastic neutron scatterings have been performed and these have indicated the realisation of the design specifications and performance of the instrument.

  10. The International Space Station's Multi-Purpose Logistics Module, Thermal Performance of the First Five Flights

    NASA Technical Reports Server (NTRS)

    Holladay, Jon; Cho, Frank

    2003-01-01

    The Multi-Purpose Logistics Module is the primary carrier for transport of pressurized payload to the International Space Station. Performing five missions within a thirteen month span provided a unique opportunity to gather a great deal of information toward understanding and verifying the orbital performance of the vehicle. This paper will provide a brief overview of the hardware history and design capabilities followed by a summary of the missions flown, resource requirements and possibilities for the future.

  11. Efficient Operation of a Multi-purpose Reservoir in Chile: Integration of Economic Water Value for Irrigation and Hydropower

    NASA Astrophysics Data System (ADS)

    Olivares, M. A.; Gonzalez Cabrera, J. M., Sr.; Moreno, R.

    2016-12-01

    Operation of hydropower reservoirs in Chile is prescribed by an Independent Power System Operator. This study proposes a methodology that integrates power grid operations planning with basin-scale multi-use reservoir operations planning. The aim is to efficiently manage a multi-purpose reservoir, in which hydroelectric generation is competing with other water uses, most notably irrigation. Hydropower and irrigation are competing water uses due to a seasonality mismatch. Currently, the operation of multi-purpose reservoirs with substantial power capacity is prescribed as the result of a grid-wide cost-minimization model which takes irrigation requirements as constraints. We propose advancing in the economic co-optimization of reservoir water use for irrigation and hydropower at the basin level, by explicitly introducing the economic value of water for irrigation represented by a demand function for irrigation water. The proposed methodology uses the solution of a long-term grid-wide operations planning model, a stochastic dual dynamic program (SDDP), to obtain the marginal benefit function for water use in hydropower. This marginal benefit corresponds to the energy price in the power grid as a function of the water availability in the reservoir and the hydrologic scenarios. This function allows capture technical and economic aspects to the operation of hydropower reservoir in the power grid and is generated with the dual variable of the power-balance constraint, the optimal reservoir operation and the hydrologic scenarios used in SDDP. The economic value of water for irrigation and hydropower are then integrated into a basin scale stochastic dynamic program, from which stored water value functions are derived. These value functions are then used to re-optimize reservoir operations under several inflow scenarios.

  12. Elimination of biofilm and microbial contamination reservoirs in hospital washbasin U-bends by automated cleaning and disinfection with electrochemically activated solutions.

    PubMed

    Swan, J S; Deasy, E C; Boyle, M A; Russell, R J; O'Donnell, M J; Coleman, D C

    2016-10-01

    Washbasin U-bends are reservoirs of microbial contamination in healthcare environments. U-Bends are constantly full of water and harbour microbial biofilm. To develop an effective automated cleaning and disinfection system for U-bends using two solutions generated by electrochemical activation of brine including the disinfectant anolyte (predominantly hypochlorous acid) and catholyte (predominantly sodium hydroxide) with detergent properties. Initially three washbasin U-bends were manually filled with catholyte followed by anolyte for 5min each once weekly for five weeks. A programmable system was then developed with one washbasin that automated this process. This U-bend had three cycles of 5min catholyte followed by 5min anolyte treatment per week for three months. Quantitative bacterial counts from treated and control U-bends were determined on blood agar (CBA), R2A, PAS, and PA agars following automated treatment and on CBA and R2A following manual treatment. The average bacterial density from untreated U-bends throughout the study was >1×10(5) cfu/swab on all media with Pseudomonas aeruginosa accounting for ∼50% of counts. Manual U-bend electrochemically activated (ECA) solution treatment reduced counts significantly (<100cfu/swab) (P<0.01 for CBA; P<0.005 for R2A). Similarly, counts from the automated ECA-treatment U-bend were significantly reduced with average counts for 35 cycles on CBA, R2A, PAS, and PA of 2.1±4.5 (P<0.0001), 13.1±30.1 (P<0.05), 0.7±2.8 (P<0.001), and 0 (P<0.05) cfu/swab, respectively. P. aeruginosa was eliminated from all treated U-bends. Automated ECA treatment of washbasin U-bends consistently minimizes microbial contamination. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Restoring Natural Streamflow Variability by Modifying Multi-purpose Reservoir Operation

    NASA Astrophysics Data System (ADS)

    Shiau, J.

    2010-12-01

    Multi-purpose reservoirs typically provide benefits of water supply, hydroelectric power, and flood mitigation. Hydroelectric power generations generally do not consume water. However, temporal distribution of downstream flows is highly changed due to hydro-peaking effects. Associated with offstream diversion of water supplies for municipal, industrial, and agricultural requirements, natural streamflow characteristics of magnitude, duration, frequency, timing, and rate of change is significantly altered by multi-purpose reservoir operation. Natural flow regime has long been recognized a master factor for ecosystem health and biodiversity. Restoration of altered flow regime caused by multi-purpose reservoir operation is the main objective of this study. This study presents an optimization framework that modifying reservoir operation to seeking balance between human and environmental needs. The methodology presented in this study is applied to the Feitsui Reservoir, located in northern Taiwan, with main purpose of providing stable water-supply and auxiliary purpose of electricity generation and flood-peak attenuation. Reservoir releases are dominated by two decision variables, i.e., duration of water releases for each day and percentage of daily required releases within the duration. The current releasing policy of the Feitsui Reservoir releases water for water-supply and hydropower purposes during 8:00 am to 16:00 pm each day and no environmental flows releases. Although greater power generation is obtained by 100% releases distributed within 8-hour period, severe temporal alteration of streamflow is observed downstream of the reservoir. Modifying reservoir operation by relaxing these two variables and reserve certain ratio of streamflow as environmental flow to maintain downstream natural variability. The optimal reservoir releasing policy is searched by the multi-criterion decision making technique for considering reservoir performance in terms of shortage ratio

  14. Programmable Thermostat Module Upgrade for the Multi-Purpose Logistics Module

    NASA Technical Reports Server (NTRS)

    Clark, Dallas; Glasgow, Shaun; Reagan, Shawn; Presson, Keith; Howard, David; Smith, Dennis

    2007-01-01

    The STS-121/ULF1.1 mission was the maiden flight of the Programmable Thermostat Module (PTM) system used to control the 28 V shell heaters on the Multi-Purpose Logistics Module (MPLM). These PTMs, in conjunction with a Data Recorder Module (DRM), provide continuous closed loop temperature control and data recording of MPLM on-orbit heater operations. This paper will discuss the hardware design, development, test and verification (DDT&V) activities performed at the Marshall Space Flight Center (MSFC) as well as the operational implementation and mission performance.

  15. A multi-purpose SAIL demonstrator design and its principle experimental verification

    NASA Astrophysics Data System (ADS)

    Zhou, Yu; Yan, Aimin; Xu, Nan; Wang, Lijuan; Luan, Zhu; Sun, Jianfeng; Liu, Liren

    2009-08-01

    A fully 2-D synthetic aperture imaging ladar (SAIL) demonstrator is designed and being fabricated to experimentally investigate and theoretically analyze the beam diffraction properties, antenna function, imaging resolution and signal processing algorithm of SAIL. The design details of the multi-purpose SAIL demonstrator are given and, as the first phase, a laboratory-scaled SAIL system based on bulk optical elements has been built to verify the principle of design, which is similar in construction to the demonstrator but without the major antenna telescope. The system has the aperture diameter of about 1mm and the target distance of 3.2m.

  16. The Multi-Purpose Detector for NICA heavy-Ion Collider at JINR

    SciTech Connect

    Rogachevsky, O. V.

    2012-05-15

    The Multi-Purpose Detector (MPD) is designed to study heavy-ion collisions at the Nuclotron-based heavy Ion Collider fAcility (NICA) at JINR, Dubna. Its main components located inside a superconducting solenoid are a tracking system composed of a silicon microstrip vertex detector followed by a large volume time-projection chamber, a time-of-flight system for particle identification and a barrel electromagnetic calorimeter. A zero degree hadron calorimeter is designed specifically to measure the energy of spectators. In this paper, all parts of the apparatus are described and their tracking and particle identification parameters are discussed in some detail.

  17. Disinfection of gloves: feasible, but pay attention to the disinfectant/glove combination.

    PubMed

    Scheithauer, S; Häfner, H; Seef, R; Seef, S; Hilgers, R D; Lemmen, S

    2016-11-01

    Compliance with hand hygiene is complicated by indications for hand disinfection in rapid succession during the care of one patient. In such situations, disinfection of gloves could facilitate better workflow and optimize compliance rates. We analysed the efficacy of disinfecting gloves by comparing an individual effect of five different hand disinfectant solutions in combination with three different glove types. The investigation was performed in accordance with DIN EN 1500:2013. For all combinations, ten analyses were performed, including (1) right/left-hand examination disinfection efficacy after the first and fifth contamination with E. coli K12 NCTC 10538, (2) recovery rates after contamination, (3) reduction efficacy, (4) fingertip immersion culture, and (5) check for tightness. Disinfection of the ungloved hands was taken as an additional benchmark. The disinfection efficacy for all disinfectant/glove combinations was better with rather than without gloves. For eight combinations, the disinfection efficacy was always >5.0 log10. There were significant differences within the gloves (P=0.0021) and within the disinfectant product (P=0.0023), respectively. In detail, Nitril Blue Eco-Plus performed significantly better than Vasco Braun (P=0.0017) and Latex Med Comfort (P=0.0493). Descoderm showed a significantly worse performance than Promanum pure (P=0.043). In the check for tightness, only the Vasco Braun gloves showed no leaks in all samples. There were relevant qualitative differences pertaining to the comfort of disinfecting gloves. The disinfection efficacy for the different disinfectant/glove combinations was greater than for the ungloved hands. However, various disinfectant/glove combinations produce relevant differences as regards disinfection efficacy. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  18. MODELING DISINFECTANT RESIDUALS IN DRINKING-WATER STORAGE TANKS

    EPA Science Inventory

    The factors leading to the loss of disinfectant residual in well-mixed drinking-water storage tanks are studied. Equations relating disinfectant residual to the disinfectant's reation rate, the tank volume, and the fill and drain rates are presented. An analytical solution for ...

  19. MODELING DISINFECTANT RESIDUALS IN DRINKING-WATER STORAGE TANKS

    EPA Science Inventory

    The factors leading to the loss of disinfectant residual in well-mixed drinking-water storage tanks are studied. Equations relating disinfectant residual to the disinfectant's reation rate, the tank volume, and the fill and drain rates are presented. An analytical solution for ...

  20. Conceptual design for an AIUC multi-purpose spectrograph camera using DMD technology

    NASA Astrophysics Data System (ADS)

    Rukdee, S.; Bauer, F.; Drass, H.; Vanzi, L.; Jordan, A.; Barrientos, F.

    2017-02-01

    Current and upcoming massive astronomical surveys are expected to discover a torrent of objects, which need groundbased follow-up observations to characterize their nature. For transient objects in particular, rapid early and efficient spectroscopic identification is needed. In particular, a small-field Integral Field Unit (IFU) would mitigate traditional slit losses and acquisition time. To this end, we present the design of a Digital Micromirror Device (DMD) multi-purpose spectrograph camera capable of running in several modes: traditional longslit, small-field patrol IFU, multi-object and full-field IFU mode via Hadamard spectra reconstruction. AIUC Optical multi-purpose CAMera (AIUCOCAM) is a low-resolution spectrograph camera of R 1,600 covering the spectral range of 0.45-0.85 μm. We employ a VPH grating as a disperser, which is removable to allow an imaging mode. This spectrograph is envisioned for use on a 1-2 m class telescope in Chile to take advantage of good site conditions. We present design decisions and challenges for a costeffective robotized spectrograph. The resulting instrument is remarkably versatile, capable of addressing a wide range of scientific topics.

  1. Multi-Purpose Low Voltage Dual Output DC-DC Converter For 100V Power Bus Telecom Platform

    NASA Astrophysics Data System (ADS)

    Galiana, D.; Mollard, J. M.

    2011-10-01

    The decreasing supply voltages of digital electronic and high speed ADC (Analog to Digital Converter) and DAC (Digital to Analog Converter) require flexible and high current secondary power distribution system. In the frame of the Inmarsat I-XL program, a 12 kW geomobile SatCom satellite, with 100 V regulated power bus, a multi purpose dual output converter was developed for the payload processor as a building block. After a short introduction on the main performance requirements, the baseline architecture is presented. The main drivers of the architecture are reliability, adjustability, radiation tolerant and single event free, volume and mass. The combination of all these constraints highlights the need of significant breakthrough in various domains. Many research results related to packaging and power electronic topics are brought up. These results directly drive the adopted solution presented in the next step followed by a description of the integration of the defined building block in the Inmarsat I-XL payload IP (Integrated Processor). Finally, the main electrical performances such as output ripple and spikes, load step transient and stability are summarized.

  2. The Raffaello, a Multi-Purpose Logistics Module, arrives at KSC aboard a Beluga super transporter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An Airbus Industrie A300-600ST 'Beluga' Super Transporter is reflected in the rain puddles as it taxis toward the mate/demate tower at the Shuttle Landing Facility. The Beluga is carrying the Raffaello, the second Multi-Purpose Logistics Module (MPLM) for the International Space Station (ISS). One of Italy's major contributions to the ISS program, the MPLM is a reusable logistics carrier and the primary delivery system used to resupply and return station cargo requiring a pressurized environment. Weighing nearly 4.5 tons, the module measures 21 feet long and 15 feet in diameter. Raffaello will join Leonardo, the first Italian-built MPLM, in the Space Station Processing Facility for testing. NASA, Boeing, the Italian Space Agency and Alenia Aerospazio will provide engineering support.

  3. The Raffaello, a Multi-Purpose Logistics Module, arrives at KSC aboard a Beluga super transporter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An Airbus Industrie A300-600ST 'Beluga' Super Transporter touches down at the Shuttle Landing Facility to deliver its cargo, the second Multi-Purpose Logistics Module (MPLM) for the International Space Station (ISS). One of Italy's major contributions to the ISS program, the MPLM, named Raffaello, is a reusable logistics carrier and the primary delivery system used to resupply and return station cargo requiring a pressurized environment. Weighing nearly 4.5 tons, the module measures 21 feet long and 15 feet in diameter. Raffaello will join Leonardo, the first Italian-built MPLM, in the Space Station Processing Facility for testing. NASA, Boeing, the Italian Space Agency and Alenia Aerospazio will provide engineering support.

  4. Orion Multi Purpose Crew Vehicle Environmental Control and Life Support Development Status

    NASA Technical Reports Server (NTRS)

    Lewis, John F.; Barido, Richard A.; Cross, Cynthia D.; Carrasquillo, Robyn; Rains, George Edward

    2012-01-01

    The Orion Multi Purpose Crew Vehicle (MPCV) is the first crew transport vehicle to be developed by the National Aeronautics and Space Administration (NASA) in the last thirty years. Orion is currently being developed to transport the crew safely from the Earth beyond Earth orbit. This year, the vehicle focused on building the Exploration Flight Test 1 (EFT1) vehicle to be launched in 2014. The development of the Orion Environmental Control and Life Support (ECLS) System, focused on the components which are on EFT1 which includes pressure control and active thermal control systems, is progressing through the design stage into manufacturing. Additional development work was done to keep the remaining component progressing towards implementation for a flight tests in 2017 and in 2020. This paper covers the Orion ECLS development from April 2011 to April 2012.

  5. NASA AND ESA Partnership on the Multi-Purpose Crew Vehicle Service Module

    NASA Technical Reports Server (NTRS)

    Free, James M.; Schubert, Kathleen; Grantier, Julie

    2012-01-01

    In March 2011, NASA and ESA made a decision to partially offset the European obligations deriving from the extension of the ISS Program until the end of 2020 with different means than ATVs, following the ATV-5 mission foreseen in mid-2014. NASA and ESA considered a number of barter options, and concluded that the provision by ESA of the Service Module and Spacecraft Adaptor for the NASA Multi-Purpose Crew Vehicle (MPCV) was the barter element with the most interest. A joint ESA - NASA working group was established to assess the feasibility of Europe developing this Module based on ATV heritage. The working group was supported by European and US industry namely Astrium, TAS-I and Lockheed-Martin. This paper gives an overview of the results of the on-going study as well as its projected utilization for the global space exploration endeavour.

  6. Descent and Landing Triggers for the Orion Multi-Purpose Crew Vehicle Exploration Flight Test-1

    NASA Technical Reports Server (NTRS)

    Bihari, Brian D.; Semrau, Jeffrey D.; Duke, Charity J.

    2013-01-01

    The Orion Multi-Purpose Crew Vehicle (MPCV) will perform a flight test known as Exploration Flight Test-1 (EFT-1) currently scheduled for 2014. One of the primary functions of this test is to exercise all of the important Guidance, Navigation, Control (GN&C), and Propulsion systems, along with the flight software for future flights. The Descent and Landing segment of the flight is governed by the requirements levied on the GN&C system by the Landing and Recovery System (LRS). The LRS is a complex system of parachutes and flight control modes that ensure that the Orion MPCV safely lands at its designated target in the Pacific Ocean. The Descent and Landing segment begins with the jettisoning of the Forward Bay Cover and concludes with sensing touchdown. This paper discusses the requirements, design, testing, analysis and performance of the current EFT-1 Descent and Landing Triggers flight software.

  7. Multi-Purpose Avionic Architecture for Vision Based Navigation Systems for EDL and Surface Mobility Scenarios

    NASA Astrophysics Data System (ADS)

    Tramutola, A.; Paltro, D.; Cabalo Perucha, M. P.; Paar, G.; Steiner, J.; Barrio, A. M.

    2015-09-01

    Vision Based Navigation (VBNAV) has been identified as a valid technology to support space exploration because it can improve autonomy and safety of space missions. Several mission scenarios can benefit from the VBNAV: Rendezvous & Docking, Fly-Bys, Interplanetary cruise, Entry Descent and Landing (EDL) and Planetary Surface exploration. For some of them VBNAV can improve the accuracy in state estimation as additional relative navigation sensor or as absolute navigation sensor. For some others, like surface mobility and terrain exploration for path identification and planning, VBNAV is mandatory. This paper presents the general avionic architecture of a Vision Based System as defined in the frame of the ESA R&T study “Multi-purpose Vision-based Navigation System Engineering Model - part 1 (VisNav-EM-1)” with special focus on the surface mobility application.

  8. MATISSE: Multi-purpose Advanced Tool for Instruments for the Solar System Exploration

    NASA Astrophysics Data System (ADS)

    Zinzi, A.; Capria, M. T.; Antonelli, L. A.

    2013-09-01

    In planetary sciences, design, assemble and launch onboard instruments are only preliminary steps toward the final aim of converting data into scientific knowledge, as the real challenge is the data analysis and interpretation. Up to now data have been generally stored in "old style" archives, i.e. common ftp servers where the user can manually search for data browsing directories organized in a time order manner. However, as datasets to be stored and searched become particularly large, this latter task absorb a great part of the time, subtracting time to the real scientific work. In order to reduce the time spent to search and analyze data MATISSE (Multi-purpose Advanced Tool for Instruments for the Solar System Exploration), a new set of software tools developed together with the scientific teams of the instruments involved, is under development at ASDC (ASI Science Data Center), whose experience in space missions data management is well known (e.g., [1], [2], [3], [4]).

  9. Raffaello Multi-Purpose Logistics Module (MPLM) in Discovery Cargo Bay

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Launched on July 26, 2005 from the Kennedy Space Center in Florida, STS-114 was classified as Logistics Flight 1. Among the Station-related activities of the mission were the delivery of new supplies and the replacement of one of the orbital outpost's Control Moment Gyroscopes (CMGs). STS-114 also carried the Raffaello Multi-Purpose Logistics Module (MPLM) and the External Stowage Platform-2. Back dropped by popcorn-like clouds, the MPLM can be seen in the cargo bay as Discovery undergoes rendezvous and docking operations. Cosmonaut Sergei K. Kriklev, Expedition 11 Commander, and John L. Phillips, NASA Space Station officer and flight engineer photographed the spacecraft from the International Space Station (ISS).

  10. Raffaello Multi-Purpose Logistics Module (MPLM) in Discovery Cargo Bay

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Launched on July 26 2005 from the Kennedy Space Center in Florida, STS-114 was classified as Logistics Flight 1. Among the Station-related activities of the mission were the delivery of new supplies and the replacement of one of the orbital outpost's Control Moment Gyroscopes (CMGs). STS-114 also carried the Raffaello Multi-Purpose Logistics Module (MPLM) and the External Stowage Platform-2. Back dropped by popcorn-like clouds, the MPLM can be seen in the cargo bay as Discovery undergoes rendezvous and docking operations. Cosmonaut Sergei K. Kriklev, Expedition 11 Commander, and John L. Phillips, NASA Space Station officer and flight engineer photographed the spacecraft from the International Space Station (ISS).

  11. The Raffaello, a Multi-Purpose Logistics Module, arrives at KSC aboard a Beluga super transporter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An Airbus Industrie A300-600ST 'Beluga' Super Transporter is reflected in the rain puddles as it comes to a stop at the Shuttle Landing Facility. The Beluga is carrying the Raffaello, the second Multi-Purpose Logistics Module (MPLM) for the International Space Station (ISS). One of Italy's major contributions to the ISS program, the MPLM is a reusable logistics carrier and the primary delivery system used to resupply and return station cargo requiring a pressurized environment. Weighing nearly 4.5 tons, the module measures 21 feet long and 15 feet in diameter. Raffaello will join Leonardo, the first Italian-built MPLM, in the Space Station Processing Facility for testing. NASA, Boeing, the Italian Space Agency and Alenia Aerospazio will provide engineering support.

  12. The Raffaello, a Multi-Purpose Logistics Module, arrives at KSC aboard a Beluga super transporter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An Airbus Industrie A300-600ST 'Beluga' Super Transporter is reflected in the rain puddles as it taxis toward the mate/demate tower at the Shuttle Landing Facility. The Beluga is carrying the Raffaello, the second Multi-Purpose Logistics Module (MPLM) for the International Space Station (ISS). One of Italy's major contributions to the ISS program, the MPLM is a reusable logistics carrier and the primary delivery system used to resupply and return station cargo requiring a pressurized environment. Weighing nearly 4.5 tons, the module measures 21 feet long and 15 feet in diameter. Raffaello will join Leonardo, the first Italian-built MPLM, in the Space Station Processing Facility for testing. NASA, Boeing, the Italian Space Agency and Alenia Aerospazio will provide engineering support.

  13. The Raffaello, a Multi-Purpose Logistics Module, arrives at KSC aboard a Beluga super transporter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An Airbus Industrie A300-600ST 'Beluga' Super Transporter lands in the rain at the Shuttle Landing Facility to deliver its cargo, the second Multi-Purpose Logistics Module (MPLM) for the International Space Station (ISS). One of Italy's major contributions to the ISS program, the MPLM, named Raffaello, is a reusable logistics carrier and the primary delivery system used to resupply and return station cargo requiring a pressurized environment. Weighing nearly 4.5 tons, the module measures 21 feet long and 15 feet in diameter. Raffaello will join Leonardo, the first Italian-built MPLM, in the Space Station Processing Facility for testing. NASA, Boeing, the Italian Space Agency and Alenia Aerospazio will provide engineering support.

  14. The Raffaello, a Multi-Purpose Logistics Module, arrives at KSC aboard a Beluga super transporter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An Airbus Industrie A300-600ST 'Beluga' Super Transporter touches down at the Shuttle Landing Facility to deliver its cargo, the second Multi-Purpose Logistics Module (MPLM) for the International Space Station (ISS). One of Italy's major contributions to the ISS program, the MPLM, named Raffaello, is a reusable logistics carrier and the primary delivery system used to resupply and return station cargo requiring a pressurized environment. Weighing nearly 4.5 tons, the module measures 21 feet long and 15 feet in diameter. Raffaello will join Leonardo, the first Italian-built MPLM, in the Space Station Processing Facility for testing. NASA, Boeing, the Italian Space Agency and Alenia Aerospazio will provide engineering support.

  15. Multi Purpose Crew Vehicle Environmental Control and Life Support Development Status

    NASA Technical Reports Server (NTRS)

    Lewis, John F.; Barido, Richard A.; Cross, Cynthia D.; Carrasquillo, Robyn; Rains, George Edward

    2011-01-01

    The Orion Multi Purpose Crew Vehicle (MPCV) is the first crew transport vehicle to be developed by the National Aeronautics and Space Administration (NASA) in the last thirty years. Orion is currently being developed to transport the crew safely from the Earth beyond Earth orbit. This year, the vehicle focused on building the Orion Flight Test 1 (OFT1) vehicle to be launched in 2013. The development of the Orion Environmental Control and Life Support (ECLS) System, focused on the components which are on OFT1 which includes pressure control and active thermal control systems, is progressing through the design stage into manufacturing. Additional development work was done to keep the remaining component progressing towards implementation for a flight test in 2017. This paper covers the Orion ECLS development from April 2011 to April 2012.

  16. Multi Purpose Crew Vehicle Active Thermal Control and Environmental Control and Life Support Development Status

    NASA Technical Reports Server (NTRS)

    Lewis, John F.; Barido, Richard A.; Boehm, Paul; Cross, Cynthia D.; Rains, George Edward

    2014-01-01

    The Orion Multi Purpose Crew Vehicle (MPCV) is the first crew transport vehicle to be developed by the National Aeronautics and Space Administration (NASA) in the last thirty years. Orion is currently being developed to transport the crew safely beyond Earth orbit. This year, the vehicle focused on building the Exploration Flight Test 1 (EFT1) vehicle to be launched in September of 2014. The development of the Orion Active Thermal Control (ATCS) and Environmental Control and Life Support (ECLS) System, focused on the integrating the components into the EFT1 vehicle and preparing them for launch. Work also has started on preliminary design reviews for the manned vehicle. Additional development work is underway to keep the remaining component progressing towards implementation on the flight tests of EM1 in 2017 and of EM2 in 2020. This paper covers the Orion ECLS development from April 2013 to April 2014

  17. Multi Purpose Crew Vehicle Environmental Control and Life Support Development Status

    NASA Technical Reports Server (NTRS)

    Lewis, John F.; Barido, Richard A.; Cross, Cynthia D.; Rains, George Edward

    2012-01-01

    The Orion Multi Purpose Crew Vehicle (MPCV) is the first crew transport vehicle to be developed by the National Aeronautics and Space Administration (NASA) in the last thirty years. Orion is currently being developed to transport the crew safely beyond Earth orbit. This year, the vehicle focused on building the Exploration Flight Test 1 (EFT1) vehicle to be launched in 2014. The development of the Orion Environmental Control and Life Support (ECLS) System, focused on the completing the components which are on EFT1. Additional development work has been done to keep the remaining component progressing towards implementation for a flight tests in of EM1 in 2017 and in and EM2 in 2020. This paper covers the Orion ECLS development from April 2012 to April 2013.

  18. Controlling levonorgestrel binding and release in a multi-purpose prevention technology vaginal ring device.

    PubMed

    Murphy, Diarmaid J; Boyd, Peter; McCoy, Clare F; Kumar, Sandeep; Holt, Jonathon D S; Blanda, Wendy; Brimer, Andrew N; Malcolm, R Karl

    2016-03-28

    Despite a long history of incorporating steroids into silicone elastomers for drug delivery applications, little is presently known about the propensity for irreversible drug binding in these systems. In this study, the ability of the contraceptive progestin levonorgestrel to bind chemically with hydrosilane groups in addition-cure silicone elastomers has been thoroughly investigated. Cure time, cure temperature, levonorgestrel particle size, initial levonorgestrel loading and silicone elastomer type were demonstrated to be key parameters impacting the extent of levonorgestrel binding, each through their influence on the solubility of levonorgestrel in the silicone elastomer. Understanding and overcoming this levonorgestrel binding phenomenon is critical for the ongoing development of a number of drug delivery products, including a multi-purpose technology vaginal ring device offering simultaneous release of levonorgestrel and dapivirine - a lead candidate antiretroviral microbicide - for combination HIV prevention and hormonal contraception. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Raffaello Multi-Purpose Logistics Module (MPLM) in Discovery Cargo Bay

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Launched on July 26, 2005 from the Kennedy Space Center in Florida, STS-114 was classified as Logistics Flight 1. Among the Station-related activities of the mission were the delivery of new supplies and the replacement of one of the orbital outpost's Control Moment Gyroscopes (CMGs). STS-114 also carried the Raffaello Multi-Purpose Logistics Module (MPLM) and the External Stowage Platform-2. Back dropped by popcorn-like clouds, the MPLM can be seen in the cargo bay as Discovery undergoes rendezvous and docking operations. Cosmonaut Sergei K. Kriklev, Expedition 11 Commander, and John L. Phillips, NASA Space Station officer and flight engineer photographed the spacecraft from the International Space Station (ISS).

  20. Raffaello Multi-Purpose Logistics Module (MPLM) in Discovery Cargo Bay

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Launched on July 26 2005 from the Kennedy Space Center in Florida, STS-114 was classified as Logistics Flight 1. Among the Station-related activities of the mission were the delivery of new supplies and the replacement of one of the orbital outpost's Control Moment Gyroscopes (CMGs). STS-114 also carried the Raffaello Multi-Purpose Logistics Module (MPLM) and the External Stowage Platform-2. Back dropped by popcorn-like clouds, the MPLM can be seen in the cargo bay as Discovery undergoes rendezvous and docking operations. Cosmonaut Sergei K. Kriklev, Expedition 11 Commander, and John L. Phillips, NASA Space Station officer and flight engineer photographed the spacecraft from the International Space Station (ISS).

  1. The Raffaello, a Multi-Purpose Logistics Module, arrives at KSC aboard a Beluga super transporter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An Airbus Industrie A300-600ST 'Beluga' Super Transporter is reflected in the rain puddles as it comes to a stop at the Shuttle Landing Facility. The Beluga is carrying the Raffaello, the second Multi-Purpose Logistics Module (MPLM) for the International Space Station (ISS). One of Italy's major contributions to the ISS program, the MPLM is a reusable logistics carrier and the primary delivery system used to resupply and return station cargo requiring a pressurized environment. Weighing nearly 4.5 tons, the module measures 21 feet long and 15 feet in diameter. Raffaello will join Leonardo, the first Italian-built MPLM, in the Space Station Processing Facility for testing. NASA, Boeing, the Italian Space Agency and Alenia Aerospazio will provide engineering support.

  2. The Raffaello, a Multi-Purpose Logistics Module, arrives at KSC aboard a Beluga super transporter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An Airbus Industrie A300-600ST 'Beluga' Super Transporter lands in the rain at the Shuttle Landing Facility to deliver its cargo, the second Multi-Purpose Logistics Module (MPLM) for the International Space Station (ISS). One of Italy's major contributions to the ISS program, the MPLM, named Raffaello, is a reusable logistics carrier and the primary delivery system used to resupply and return station cargo requiring a pressurized environment. Weighing nearly 4.5 tons, the module measures 21 feet long and 15 feet in diameter. Raffaello will join Leonardo, the first Italian-built MPLM, in the Space Station Processing Facility for testing. NASA, Boeing, the Italian Space Agency and Alenia Aerospazio will provide engineering support.

  3. Effect of Disinfectants on Glucose Monitors

    PubMed Central

    Mahoney, John J; Lim, Christine G

    2012-01-01

    Background Monitoring blood glucose levels is an integral part of routine diabetes management. To minimize the risk of transmission of bloodborne pathogens during monitoring, the Centers for Disease Control and Prevention (CDC) recommends that glucose meters be disinfected after each use whenever they are used to test multiple patients. The objective of this study is to assess the compatibility of some common disinfectants with certain blood glucose meter systems. Methods We tested six disinfectants for adverse impact on meter performance or the exterior meter surfaces. The disinfectants tested were 0.525% sodium hypochlorite, 20% 2-propanol and 10% ethanol, 17.2% isopropanol, 55% isopropanol, 70% isopropanol, and hydrogen peroxide. To assess meter performance, we tested OneTouch® Ultra® blood glucose monitoring systems with control solution before and after application of either water or disinfectant. To assess the effect on exterior meter surfaces, we performed a soaking test to simulate long-term exposure to disinfectant. Results Paired t-test results showed that the control solution data associated with disinfectant and with water application were not significantly different for each meter type. However, most of the meter types were adversely affected by hydrogen peroxide and/or by the higher concentrations of alcohol-based disinfectants. Conclusions Although none of the six disinfectants affected meter performance, hydrogen peroxide and isopropanol >20% adversely affected the exterior surfaces of the tested meters. When complying with CDC instructions for meter disinfection, users should use caution and choose disinfectants that have been validated by the meter manufacturer. PMID:22401326

  4. Effect of disinfectants on glucose monitors.

    PubMed

    Mahoney, John J; Lim, Christine G

    2012-01-01

    Monitoring blood glucose levels is an integral part of routine diabetes management. To minimize the risk of transmission of bloodborne pathogens during monitoring, the Centers for Disease Control and Prevention (CDC) recommends that glucose meters be disinfected after each use whenever they are used to test multiple patients. The objective of this study is to assess the compatibility of some common disinfectants with certain blood glucose meter systems. We tested six disinfectants for adverse impact on meter performance or the exterior meter surfaces. The disinfectants tested were 0.525% sodium hypochlorite, 20% 2-propanol and 10% ethanol, 17.2% isopropanol, 55% isopropanol, 70% isopropanol, and hydrogen peroxide. To assess meter performance, we tested OneTouch® Ultra® blood glucose monitoring systems with control solution before and after application of either water or disinfectant. To assess the effect on exterior meter surfaces, we performed a soaking test to simulate long-term exposure to disinfectant. Paired t-test results showed that the control solution data associated with disinfectant and with water application were not significantly different for each meter type. However, most of the meter types were adversely affected by hydrogen peroxide and/or by the higher concentrations of alcohol-based disinfectants. Although none of the six disinfectants affected meter performance, hydrogen peroxide and isopropanol >20% adversely affected the exterior surfaces of the tested meters. When complying with CDC instructions for meter disinfection, users should use caution and choose disinfectants that have been validated by the meter manufacturer. © 2012 Diabetes Technology Society.

  5. Dimensional changes in stone models simulating full crown preparations with adjacent teeth resulting from long-term immersion of medium-viscosity addition-type silicone rubber impressions in disinfectant solutions.

    PubMed

    Hiraguchi, Hisako; Iwasaki, Yukiko; Iwasaki, Eriko; Kikuchi, Hisaji; Hirose, Hideharu; Yoneyama, Takayuki

    2015-01-01

    If impression materials could be immersed in disinfectant solutions for a longer period, then this form of disinfection would be easier to incorporate into dental preparation procedures. This study investigated the dimensional changes in stone models resulting from immersion of medium-viscosity hydrophilic addition-type silicone rubber impression material in disinfectant solutions for 30 min and 24 h. Impressions of a master die designed to simulate a full crown preparation with adjacent teeth were immersed in 2% glutaraldehyde and 0.55% ortho-phthalaldehyde solutions. The dimensional changes in the mesiodistal and buccolingual dimensions in the stone models were then measured using a three-dimensional coordinate system. It was found that the dimensional changes in the stone models caused by immersion of the impression materials were less than 15 μm. Immersion in 2% glutaraldehyde or 0.55% ortho-phthalaldehyde for 24 h was as clinically acceptable for medium-viscosity hydrophilic addition-type silicone rubber impressions as immersion for 30 min.

  6. Zonal management of multi-purposes groundwater utilization based on water quality and impact on the aquifer.

    PubMed

    Liang, Ching-Ping; Jang, Cheng-Shin; Chen, Ching-Fang; Chen, Jui-Sheng

    2016-07-01

    Groundwater is widely used for drinking, irrigation, and aquaculture in the Pingtung Plain, Southwestern Taiwan. The overexploitation and poor quality of groundwater in some areas of the Pingtung Plain pose great challenges for the safe use and sustainable management of groundwater resources. Thus, establishing an effective management plan for multi-purpose groundwater utilization in the Pingtung Plain is imperative. Considerations of the quality of the groundwater and potential impact on the aquifer of groundwater exploitation are paramount to multi-purpose groundwater utilization management. This study proposes a zonal management plan for the multi-purpose use of groundwater in the Pingtung Plain. The zonal management plan is developed by considering the spatial variability of the groundwater quality and the impact on the aquifer, which is defined as the ratio of the actual groundwater extraction rate to transmissivity. A geostatistical Kriging approach is used to spatially delineate the safe zones based on the water quality standards applied in the three groundwater utilization sectors. Suitable zones for the impact on the aquifer are then spatially determined. The evaluation results showing the safe water quality zones for the three types of utilization demands and suitable zones for the impact on aquifer are integrated to create a zonal management map for multi-purpose groundwater utilization which can help government administrators to establish a water resource management strategy for safe and sustainable use of groundwater to meet multi-purpose groundwater utilization requirements in the Pingtung Plain.

  7. Colonic mucosal pseudolipomatosis: disinfectant colitis?

    PubMed

    Kim, Su Jin; Baek, Il Hyun

    2012-01-01

    Colonic pseudolipomatosis is rare and its pathogenesis is still unclear. A number of mechanisms, including mechanical injury during an endoscopic procedure or chemical injury by disinfectant, seem to contribute to its pathogenesis. In our endoscopy unit, pseudolipomatosis occurred in an epidemic pattern after changing the endoscopic disinfectant from 2% glutaraldehyde to peracetic acid compound to decrease the length of endoscope reprocessing time. We assumed that pseudolipomatosis could be a type of chemical colitis produced by the residual disinfectant solution that remained on the surface or in a channel of the endoscope after reprocessing. The aim of this report was to highlight a series of 12 cases of colonic pseudolipomatosis in order to describe the endoscopic and pathological features and discuss the harmful effect of disinfectants as a possible cause of pseudolipomatosis. To identify the cause of the lesions, we systematically reviewed each patient history and the endoscopic and histological features. From March 2004 to February 2005, 1276 colonoscopies were performed and 12 cases (0.94%) of colonic pseudolipomatosis were diagnosed at the Kangnam Sacred Heart Hospital of Hallym University. The pathogenesis of colonic pseudolipomatosis is not well-known, but our experience indicates the endoscopic disinfectant as the probable cause of pseudolipomatosis rather than either mechanical traumatic injury or intraluminal air pressure-related injury.

  8. A multi-purpose open-source triggering platform for magnetic resonance.

    PubMed

    Ruytenberg, T; Webb, A G; Beenakker, J W M

    2014-10-01

    Many MR scans need to be synchronised with external events such as the cardiac or respiratory cycles. For common physiological functions commercial trigger equipment exists, but for more experimental inputs these are not available. This paper describes the design of a multi-purpose open-source trigger platform for MR systems. The heart of the system is an open-source Arduino Due microcontroller. This microcontroller samples an analogue input and digitally processes these data to determine the trigger. The output of the microcontroller is programmed to mimic a physiological signal which is fed into the electrocardiogram (ECG) or pulse oximeter port of MR scanner. The microcontroller is connected to a Bluetooth dongle that allows wireless monitoring and control outside the scanner room. This device can be programmed to generate a trigger based on various types of input. As one example, this paper describes how it can be used as an acoustic cardiac triggering unit. For this, a plastic stethoscope is connected to a microphone which is used as an input for the system. This test setup was used to acquire retrospectively-triggered cardiac scans in ten volunteers. Analysis showed that this platform produces a reliable trigger (>99% triggers are correct) with a small average 8 ms variation between the exact trigger points.

  9. INITIAL WASTE PACKAGE PROBABILISTIC CRITICALITY ANALYSIS: MULTI-PURPOSE CANISTER WITH DISPOSAL CONTAINER (TBV)

    SciTech Connect

    J.R. Massari

    1995-10-06

    This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development Department (WPDD) to provide an assessment of the present waste package design from a criticality risk standpoint. The specific objectives of this initial analysis are to: (1) Establish a process for determining the probability of waste package criticality as a function of time (in terms of a cumulative distribution function, probability distribution function, or expected number of criticalities in a specified time interval) for various waste package concepts; (2) Demonstrate the established process by estimating the probability of criticality as a function of time since emplacement for an intact multi-purpose canister waste package (MPC-WP) configuration; (3) Identify the dominant sequences leading to waste package criticality for subsequent detailed analysis. The purpose of this analysis is to document and demonstrate the developed process as it has been applied to the MPC-WP. This revision is performed to correct deficiencies in the previous revision and provide further detail on the calculations performed. This analysis is similar to that performed for the uncanistered fuel waste package (UCF-WP, B00000000-01717-2200-00079).

  10. A case study: Transforming a vaudeville theatre into a 21st century multi-purpose hall

    NASA Astrophysics Data System (ADS)

    Talaske, Richard H.; Hoffman, Ian B.; Laney, Jonathan P.

    2002-05-01

    Originally constructed in 1927 as an atmospheric, vaudeville theatre, the Coronado enjoyed 50 years as host to a true variety of events. In the 1970s, functional and space limitations became a catalyst for touring events to avoid the Coronado, and the theatre fell into disrepair. In the mid-1990s, a renovation was planned (completed January 2001) to restore the glory of the original theatre and upgrade it to be a viable multi-purpose hall for the 21st century. By annexing two neighboring buildings, many of the space limitations could be overcome in both the front- and back-of-house. The scope included a significantly enlarged stage and stagehouse, performer support spaces, expanded lobby spaces, quiet ventilation systems, and a new music rehearsal room. Acoustically, a primary goal was to upgrade the hall for both reinforced music/theatre performances and unreinforced, orchestral performances. However, historical regulations prevented modification to the room shape and configuration. In order to make the room suitable for unreinforced music, two primary acoustic features were instituted-a semi-custom concert enclosure for the stage and an acoustic enhancement system for the audience chamber. For theatrical and popular music events, a new performance audio system was designed and integrated into the hall.

  11. Software-programmable continuous-flow multi-purpose lab-on-a-chip

    PubMed Central

    Amin, Ahmed M.; Thakur, Raviraj; Madren, Seth; Chuang, Han-Sheng; Thottethodi, Mithuna; Vijaykumar, T. N.; Wereley, Steven T.; Jacobson, Stephen C.

    2013-01-01

    Current lab-on-a-chip (LoC) devices are assay-specific and are custom-built for each single experiment. Performing an experiment requires scientists or engineers to go through the time-consuming process of designing, fabricating, and testing a chip before conducting the actual experiment. This prolonged cycle can take months to complete, increasing effort and cost and reducing productivity. Similarly, minor modifications to an assay protocol re-incur the overheads of the design cycle. In this paper, we develop a multi-purpose, software-programmableLab-on-a-Chip (SPLoC), where the user simply writes or downloads a program for each experiment. We describe the components necessary to realize the SPLoC, which include a high-level programming language, an abstract instruction set, a runtime and control system, and a microfluidic device. We describe two key features of our high-level language compiler, and describe a novel variable-volume variable-ratio mixer. Finally, we demonstrate our SPLoC on four diverse, real-world assays. PMID:24436691

  12. A multi-purpose open-source triggering platform for magnetic resonance

    NASA Astrophysics Data System (ADS)

    Ruytenberg, T.; Webb, A. G.; Beenakker, J. W. M.

    2014-10-01

    Many MR scans need to be synchronised with external events such as the cardiac or respiratory cycles. For common physiological functions commercial trigger equipment exists, but for more experimental inputs these are not available. This paper describes the design of a multi-purpose open-source trigger platform for MR systems. The heart of the system is an open-source Arduino Due microcontroller. This microcontroller samples an analogue input and digitally processes these data to determine the trigger. The output of the microcontroller is programmed to mimic a physiological signal which is fed into the electrocardiogram (ECG) or pulse oximeter port of MR scanner. The microcontroller is connected to a Bluetooth dongle that allows wireless monitoring and control outside the scanner room. This device can be programmed to generate a trigger based on various types of input. As one example, this paper describes how it can be used as an acoustic cardiac triggering unit. For this, a plastic stethoscope is connected to a microphone which is used as an input for the system. This test setup was used to acquire retrospectively-triggered cardiac scans in ten volunteers. Analysis showed that this platform produces a reliable trigger (>99% triggers are correct) with a small average 8 ms variation between the exact trigger points.

  13. Software-programmable continuous-flow multi-purpose lab-on-a-chip.

    PubMed

    Amin, Ahmed M; Thakur, Raviraj; Madren, Seth; Chuang, Han-Sheng; Thottethodi, Mithuna; Vijaykumar, T N; Wereley, Steven T; Jacobson, Stephen C

    2013-11-01

    Current lab-on-a-chip (LoC) devices are assay-specific and are custom-built for each single experiment. Performing an experiment requires scientists or engineers to go through the time-consuming process of designing, fabricating, and testing a chip before conducting the actual experiment. This prolonged cycle can take months to complete, increasing effort and cost and reducing productivity. Similarly, minor modifications to an assay protocol re-incur the overheads of the design cycle. In this paper, we develop a multi-purpose, software-programmableLab-on-a-Chip (SPLoC), where the user simply writes or downloads a program for each experiment. We describe the components necessary to realize the SPLoC, which include a high-level programming language, an abstract instruction set, a runtime and control system, and a microfluidic device. We describe two key features of our high-level language compiler, and describe a novel variable-volume variable-ratio mixer. Finally, we demonstrate our SPLoC on four diverse, real-world assays.

  14. Honeycomblike large area LaB6 plasma source for Multi-Purpose Plasma facility.

    PubMed

    Woo, Hyun-Jong; Chung, Kyu-Sun; You, Hyun-Jong; Lee, Myoung-Jae; Lho, Taihyeop; Choh, Kwon Kook; Yoon, Jung-Sik; Jung, Yong Ho; Lee, Bongju; Yoo, Suk Jae; Kwon, Myeon

    2007-10-01

    A Multi-Purpose Plasma (MP(2)) facility has been renovated from Hanbit mirror device [Kwon et al., Nucl. Fusion 43, 686 (2003)] by adopting the same philosophy of diversified plasma simulator (DiPS) [Chung et al., Contrib. Plasma Phys. 46, 354 (2006)] by installing two plasma sources: LaB(6) (dc) and helicon (rf) plasma sources; and making three distinct simulators: divertor plasma simulator, space propulsion simulator, and astrophysics simulator. During the first renovation stage, a honeycomblike large area LaB(6) (HLA-LaB(6)) cathode was developed for the divertor plasma simulator to improve the resistance against the thermal shock fragility for large and high density plasma generation. A HLA-LaB(6) cathode is composed of the one inner cathode with 4 in. diameter and the six outer cathodes with 2 in. diameter along with separate graphite heaters. The first plasma is generated with Ar gas and its properties are measured by the electric probes with various discharge currents and magnetic field configurations. Plasma density at the middle of central cell reaches up to 2.6 x 10(12) cm(-3), while the electron temperature remains around 3-3.5 eV at the low discharge current of less than 45 A, and the magnetic field intensity of 870 G. Unique features of electric property of heaters, plasma density profiles, is explained comparing with those of single LaB(6) cathode with 4 in. diameter in DiPS.

  15. MATISSE: Multi-purpose Advanced Tool for Instruments for the Solar System Exploration .

    NASA Astrophysics Data System (ADS)

    Zinzi, A.; Capria, M. T.; Antonelli, L. A.

    In planetary sciences, design, assemble and launch onboard instruments are only preliminary steps toward the final aim of converting data into scientific knowledge, as the real challenge is the data analysis and interpretation. Up to now data have been generally stored in "old style" archives, i.e. common ftp servers where the user can manually search for data browsing directories organized in a time order manner. However, as datasets to be stored and searched become particularly large, this latter task absorbs a great part of the time, subtracting time to the real scientific work. In order to reduce the time spent to search and analyze data MATISSE (Multi-purpose Advanced Tool for Instruments for the Solar System Exploration), a new set of software tools developed together with the scientific teams of the instruments involved, is under development at ASDC (ASI Science Data Center), whose experience in space missions data management is well known (e.g., \\citealt{verrecchia07,pittori09,giommi09,massaro11}) and its features and aims will be presented here.

  16. REBOUND: an open-source multi-purpose N-body code for collisional dynamics

    NASA Astrophysics Data System (ADS)

    Rein, H.; Liu, S.-F.

    2012-01-01

    REBOUND is a new multi-purpose N-body code which is freely available under an open-source license. It was designed for collisional dynamics such as planetary rings but can also solve the classical N-body problem. It is highly modular and can be customized easily to work on a wide variety of different problems in astrophysics and beyond. REBOUND comes with three symplectic integrators: leap-frog, the symplectic epicycle integrator (SEI) and a Wisdom-Holman mapping (WH). It supports open, periodic and shearing-sheet boundary conditions. REBOUND can use a Barnes-Hut tree to calculate both self-gravity and collisions. These modules are fully parallelized with MPI as well as OpenMP. The former makes use of a static domain decomposition and a distributed essential tree. Two new collision detection modules based on a plane-sweep algorithm are also implemented. The performance of the plane-sweep algorithm is superior to a tree code for simulations in which one dimension is much longer than the other two and in simulations which are quasi-two dimensional with less than one million particles. In this work, we discuss the different algorithms implemented in REBOUND, the philosophy behind the code's structure as well as implementation specific details of the different modules. We present results of accuracy and scaling tests which show that the code can run efficiently on both desktop machines and large computing clusters.

  17. REBOUND: Multi-purpose N-body code for collisional dynamics

    NASA Astrophysics Data System (ADS)

    Rein, Hanno; Liu, Shang-Fei

    2011-10-01

    REBOUND is a multi-purpose N-body code which is freely available under an open-source license. It was designed for collisional dynamics such as planetary rings but can also solve the classical N-body problem. It is highly modular and can be customized easily to work on a wide variety of different problems in astrophysics and beyond. REBOUND comes with three symplectic integrators: leap-frog, the symplectic epicycle integrator (SEI) and a Wisdom-Holman mapping (WH). It supports open, periodic and shearing-sheet boundary conditions. REBOUND can use a Barnes-Hut tree to calculate both self-gravity and collisions. These modules are fully parallelized with MPI as well as OpenMP. The former makes use of a static domain decomposition and a distributed essential tree. Two new collision detection modules based on a plane-sweep algorithm are also implemented. The performance of the plane-sweep algorithm is superior to a tree code for simulations in which one dimension is much longer than the other two and in simulations which are quasi-two dimensional with less than one million particles.

  18. A compact light-weighted and multi-purpose calibration unit for LINC-NIRVANA

    NASA Astrophysics Data System (ADS)

    De Bonis, Fulvio; Bertram, Thomas; Labadie, Lucas; Egner, Sebastian; Bizenberger, Peter; Hofferbert, Ralph; Eckart, Andreas; Kuerster, Martin; Herbst, Tom

    2010-07-01

    Laboratory and on-sky experience suggests that the integration of big astronomical instruments, specially of a complex interferometric system, is a challenging process. LINC-NIRVANA is the Fizeau interferometric imager for the Large Binocular Telescope (LBT). Simulating the final operating environment of every system component has shown how critical is the presence of flexures, vibrations and thermal expansion. Assembling and aligning the opto-mechanical sub-systems will require an absolute reference which is not affected by static displacements or positioning errors. A multi-purpose calibration unit has been designed to ensure the quality of the alignment of optics and detectors and the reliability of the mechanical setup. This new compact and light-weighted unit is characterized by sophisticated kinematics, simple mechanical design and composite materials. In addition, the reduced number of motorized axis improves the stiffness and lowers the angular displacements due to moving parts. The modular concept integrates several light sources to provide the proper calibration reference for the different sub-systems of LINC-NIRVANA. For the standard alignment of the optics an absolute reference fiber will be used. For flatfielding of the detectors the unit provides an integrating sphere, and a special rotating multi-fiber plate (infrared and visible) is used to calibrate the advanced adaptive optics and the fringe-tracking systems. A module to control non-common path aberrations (Flattening of Deformable Mirrors) is also provided.

  19. MYRRHA a multi-purpose hybrid research reactor for high-tech applications

    SciTech Connect

    Abderrahim, H. A.; Baeten, P.

    2012-07-01

    MYRRHA (Multi-purpose hYbrid Research Reactor for High-tech Applications) is the flexible experimental accelerator driven system (ADS) in development at SCK-CEN. MYRRHA is able to work both in subcritical (ADS) as in critical mode. In this way, MYRRHA will allow fuel developments for innovative reactor systems, material developments for generation IV (GEN IV) systems, material developments for fusion reactors, radioisotope production and industrial applications, such as Si-doping. MYRRHA will also demonstrate the ADS full concept by coupling the three components (accelerator, spallation target and subcritical reactor) at reasonable power level to allow operation feedback, scalable to an industrial demonstrator and allow the study of efficient transmutation of high-level nuclear waste. MYRRHA is based on the heavy liquid metal technology and so it will contribute to the development of lead fast reactor (LFR) technology and in critical mode, MYRRHA will play the role of European technology pilot plant in the roadmap for LFR. In this paper the historical evolution of MYRRHA and the rationale behind the design choices is presented and the latest configuration of the reactor core and primary system is described. (authors)

  20. NASA and ESA Partnership on the Multi-Purpose Crew Vehicle Service Module

    NASA Technical Reports Server (NTRS)

    Schubert, Kathleen E.; Grantier, Julie A.

    2012-01-01

    (1) ESA decided in its Council Meeting in March 2011 to partially offset the European ISS obligations after 2015 with different means than ATVs; (2) The envisioned approach is based on a barter element(s) that would generate cost avoidance on the NASA side; (3) NASA and ESA considered a number of Barter options, NASA concluded that the provision by ESA of the Service Module for the NASA Multi-Purpose Crew Vehicle (MPCV) was the barter with the most interest;. (4) A joint ESA - NASA working group was established in May 2011 to assess the feasibility of Europe developing this Module based on ATV heritage; (5)The working group was supported by European and US industry namely Astrium, TAS-I and Lockheed-Martin; and (6) The project is currently in phase B1 with the objective to prepare a technical and programmatic proposal for an ESA MPCV-SM development. This proposal will be one element of the package that ESA plans submit to go forward for approval by European Ministers in November 2012.

  1. Evaluation of Life Sciences Glovebox (LSG) and Multi-Purpose Crew Restraint Concepts

    NASA Technical Reports Server (NTRS)

    Whitmore, Mihriban

    2005-01-01

    Within the scope of the Multi-purpose Crew Restraints for Long Duration Spaceflights project, funded by Code U, it was proposed to conduct a series of evaluations on the ground and on the KC-135 to investigate the human factors issues concerning confined/unique workstations, such as the design of crew restraints. The usability of multiple crew restraints was evaluated for use with the Life Sciences Glovebox (LSG) and for performing general purpose tasks. The purpose of the KC-135 microgravity evaluation was to: (1) to investigate the usability and effectiveness of the concepts developed, (2) to gather recommendations for further development of the concepts, and (3) to verify the validity of the existing requirements. Some designs had already been tested during a March KC-135 evaluation, and testing revealed the need for modifications/enhancements. This flight was designed to test the new iterations, as well as some new concepts. This flight also involved higher fidelity tasks in the LSG, and the addition of load cells on the gloveports.

  2. Comparison of susceptibility of cystic-fibrosis-related and non-cystic-fibrosis-related Pseudomonas aeruginosa to chlorine-based disinfecting solutions: implications for infection prevention and ward disinfection.

    PubMed

    Moore, John E; Rendall, Jacqueline C

    2014-09-01

    Multidrug-resistant (MDR) Pseudomonas aeruginosa isolated from cystic fibrosis (CF) sputum was shown to be more tolerant to the most commonly used chlorine-based disinfecting agent in the UK, with approximately 7 out of 10 isolates surviving a residual free chlorine (RFC) concentration of 500 p.p.m., when compared with antibiotic-sensitive invasive P. aeruginosa from a non-CF blood culture source, where 8 out of 10 isolates were killed at a RFC concentration of 100 p.p.m. All CF isolates were killed at 1000 p.p.m. chlorine. Additional studies were performed to examine factors that influenced the concentration of RFC from chlorine-based (sodium dichloroisocyanurate) disinfecting agents in contact with CF sputum and their components (bacterial cells, glycocalyx) to assess the reduction of the bactericidal activity of such disinfecting agents. Pseudomonas glycocalyx had a greater inhibitory effect of chlorine deactivation than bacterial cells. Calibration curves demonstrated the relative deactivating capacity on RFC from clinical soils, in the order pus>CF sputum>wound discharge fluid/synovial fluid>ascites fluid>bile, where quantitatively each 1 % (w/v) CF sputum reduced the RFC by 43 p.p.m. Sublethal stressing of P. aeruginosa with chlorine resulted in lowered susceptibility to colistin (P = 0.0326) but not to meropenem, tobramycin or ciprofloxacin. In conclusion, heavy contamination of healthcare fomites with CF sputum containing MDR P. aeruginosa may result in exhaustion of RFC, and this, combined with an increased resistance to chlorine with such strains, may lead to their survival and increased antibiotic resistance in such environments. CF infection prevention strategies in such scenarios should therefore target interventions with increased concentrations of chlorine to ensure the eradication of MDR P. aeruginosa from the CF healthcare environment.

  3. HyBIS - a low cost, multi-purpose, modular vehicle for detailed ocean mapping

    NASA Astrophysics Data System (ADS)

    Huehnerbach, V.; Murton, B.; Berndt, C.; Garrard, J.; Wollatz-Vogt, M.; Wetzel, G.; Matthiessen, T.

    2013-12-01

    HyBIS is a low-cost, multi-purpose, highly maneuverable, fibre-optic controlled survey and sampling robotic underwater vehicle (RUV) capable of diving to 6000m. Built in the UK by Hydro-Lek Ltd. in collaboration with the National Oceanography Centre, Southampton, it has proven itself during recent discoveries of the deepest hydrothermal vents in the world, at 5100m deep in the Cayman Trough in the Caribbean and habitat mapping of seamounts in the Atlantic and Indian oceans . The vehicle has a modular design, with the top module being a command and power system that comprises power management, cameras, lights, hydraulics, thrusters and telemetry. The lower module can alternatively be a clam-shell sampling grab, a manipulator-arm and tool sled, a winch for instrument recovery, or an ocean bottom seismometer deployment module. Unlike a conventional ROV, HyBIS does not have any floatation, rather it is suspended by its umbilical cable directly from the ship. The advantage of direct suspension is that HyBIS can recover or deploy a payload of up to 700kg, although this comes at the price of reduced maneuverability compared to a 'normal' ROV. During its four years of service, HyBIS has, so far, accumulated an impressive list of achievements: recording over 450 hours of HD video footage, thousands of HD still images, collected geological, biological samples, as well as fluids and gas from over 40 different sites. It has also recovered two different seabed landers containing scientific equipment worth over £300k, and placed Ocean Bottom Seismometers onto the seafloor.

  4. Forward Bay Cover Separation Modeling and Testing for the Orion Multi-Purpose Crew Vehicle

    NASA Technical Reports Server (NTRS)

    Ali, Yasmin; Radke, Tara; Chuhta, Jesse; Hughes, Michael

    2014-01-01

    Spacecraft multi-body separation events during atmospheric descent require complex testing and analysis to validate the flight separation dynamics model and to verify no recontact. NASA Orion Multi-Purpose Crew Vehicle (MPCV) teams examined key model parameters and risk areas to develop a robust but affordable test campaign in order to validate and verify the Forward Bay Cover (FBC) separation event for Exploration Flight Test-1 (EFT-1). The FBC jettison simulation model is highly complex, consisting of dozens of parameters varied simultaneously, with numerous multi-parameter interactions (coupling and feedback) among the various model elements, and encompassing distinct near-field, mid-field, and far-field regimes. The test campaign was composed of component-level testing (for example gas-piston thrusters and parachute mortars), ground FBC jettison tests, and FBC jettison air-drop tests that were accomplished by a highly multi-disciplinary team. Three ground jettison tests isolated the testing of mechanisms and structures to anchor the simulation models excluding aerodynamic effects. Subsequently, two air-drop tests added aerodynamic and parachute parameters, and served as integrated system demonstrations, which had been preliminarily explored during the Orion Pad Abort-1 (PA-1) flight test in May 2010. Both ground and drop tests provided extensive data to validate analytical models and to verify the FBC jettison event for EFT-1, but more testing is required to support human certification, for which NASA and Lockheed Martin are applying knowledge from Apollo and EFT-1 testing and modeling to develop a robust but affordable human spacecraft capability.

  5. Forward Bay Cover Separation Modeling and Testing for the Orion Multi-Purpose Crew Vehicle

    NASA Technical Reports Server (NTRS)

    Ali, Yasmin; Chuhta, Jesse D.; Hughes, Michael P.; Radke, Tara S.

    2015-01-01

    Spacecraft multi-body separation events during atmospheric descent require complex testing and analysis to validate the flight separation dynamics models used to verify no re-contact. The NASA Orion Multi-Purpose Crew Vehicle (MPCV) architecture includes a highly-integrated Forward Bay Cover (FBC) jettison assembly design that combines parachutes and piston thrusters to separate the FBC from the Crew Module (CM) and avoid re-contact. A multi-disciplinary team across numerous organizations examined key model parameters and risk areas to develop a robust but affordable test campaign in order to validate and verify the FBC separation event for Exploration Flight Test-1 (EFT-1). The FBC jettison simulation model is highly complex, consisting of dozens of parameters varied simultaneously, with numerous multi-parameter interactions (coupling and feedback) among the various model elements, and encompassing distinct near-field, mid-field, and far-field regimes. The test campaign was composed of component-level testing (for example gas-piston thrusters and parachute mortars), ground FBC jettison tests, and FBC jettison air-drop tests that were accomplished by a highly multi-disciplinary team. Three ground jettison tests isolated the testing of mechanisms and structures to anchor the simulation models excluding aerodynamic effects. Subsequently, two air-drop tests added aerodynamic and parachute elements, and served as integrated system demonstrations, which had been preliminarily explored during the Orion Pad Abort-1 (PA-1) flight test in May 2010. Both ground and drop tests provided extensive data to validate analytical models and to verify the FBC jettison event for EFT-1. Additional testing will be required to support human certification of this separation event, for which NASA and Lockheed Martin are applying knowledge from Apollo and EFT-1 testing and modeling to develop a robust human-rated FBC separation event.

  6. Honeycomblike large area LaB{sub 6} plasma source for Multi-Purpose Plasma facility

    SciTech Connect

    Woo, Hyun-Jong; Chung, Kyu-Sun; You, Hyun-Jong; Lee, Myoung-Jae; Lho, Taihyeop; Choh, Kwon Kook; Yoon, Jung-Sik; Jung, Yong Ho; Lee, Bongju; Yoo, Suk Jae; Kwon, Myeon

    2007-10-15

    A Multi-Purpose Plasma (MP{sup 2}) facility has been renovated from Hanbit mirror device [Kwon et al., Nucl. Fusion 43, 686 (2003)] by adopting the same philosophy of diversified plasma simulator (DiPS) [Chung et al., Contrib. Plasma Phys. 46, 354 (2006)] by installing two plasma sources: LaB{sub 6} (dc) and helicon (rf) plasma sources; and making three distinct simulators: divertor plasma simulator, space propulsion simulator, and astrophysics simulator. During the first renovation stage, a honeycomblike large area LaB{sub 6} (HLA-LaB{sub 6}) cathode was developed for the divertor plasma simulator to improve the resistance against the thermal shock fragility for large and high density plasma generation. A HLA-LaB{sub 6} cathode is composed of the one inner cathode with 4 in. diameter and the six outer cathodes with 2 in. diameter along with separate graphite heaters. The first plasma is generated with Ar gas and its properties are measured by the electric probes with various discharge currents and magnetic field configurations. Plasma density at the middle of central cell reaches up to 2.6x10{sup 12} cm{sup -3}, while the electron temperature remains around 3-3.5 eV at the low discharge current of less than 45 A, and the magnetic field intensity of 870 G. Unique features of electric property of heaters, plasma density profiles, is explained comparing with those of single LaB{sub 6} cathode with 4 in. diameter in DiPS.

  7. 77 FR 38582 - Proposed Information Collection; Comment Request; Domestic Client Life-Cycle Multi-Purpose Forms

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Proposed Information Collection; Comment Request; Domestic Client Life-Cycle... services and trade events to U.S. organizations. The Domestic Client Life-cycle Multi-Purpose...

  8. Evaluation Report for the ESEA Title III Project, South Bronx Multi-Purpose Supplementary Educational Center (SOMPSEC).

    ERIC Educational Resources Information Center

    North, Robert D.

    This is a report of an evaluation of the South Bronx Multi-Purpose Supplementary Educational Center (SOMPSEC). The primary objectives of SOMPSEC, funded under Title III, Elementary and Secondary Education Act were: (1) to enhance the self-image of minority-group students, (2) to encourage development of their artistic talent, and (3) to increase…

  9. 16 CFR 1145.17 - Multi-purpose lighters that can be operated by children; risks of death or injury.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... by children; risks of death or injury. 1145.17 Section 1145.17 Commercial Practices CONSUMER PRODUCT... UNDER THE CONSUMER PRODUCT SAFETY ACT § 1145.17 Multi-purpose lighters that can be operated by children; risks of death or injury. (a) The Commission finds that it is in the public interest to regulate...

  10. 16 CFR 1145.17 - Multi-purpose lighters that can be operated by children; risks of death or injury.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... by children; risks of death or injury. 1145.17 Section 1145.17 Commercial Practices CONSUMER PRODUCT... UNDER THE CONSUMER PRODUCT SAFETY ACT § 1145.17 Multi-purpose lighters that can be operated by children; risks of death or injury. (a) The Commission finds that it is in the public interest to regulate...

  11. 16 CFR 1145.17 - Multi-purpose lighters that can be operated by children; risks of death or injury.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... by children; risks of death or injury. 1145.17 Section 1145.17 Commercial Practices CONSUMER PRODUCT... UNDER THE CONSUMER PRODUCT SAFETY ACT § 1145.17 Multi-purpose lighters that can be operated by children; risks of death or injury. (a) The Commission finds that it is in the public interest to regulate...

  12. 16 CFR 1145.17 - Multi-purpose lighters that can be operated by children; risks of death or injury.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... by children; risks of death or injury. 1145.17 Section 1145.17 Commercial Practices CONSUMER PRODUCT... UNDER THE CONSUMER PRODUCT SAFETY ACT § 1145.17 Multi-purpose lighters that can be operated by children; risks of death or injury. (a) The Commission finds that it is in the public interest to regulate...

  13. 16 CFR 1145.17 - Multi-purpose lighters that can be operated by children; risks of death or injury.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... by children; risks of death or injury. 1145.17 Section 1145.17 Commercial Practices CONSUMER PRODUCT... UNDER THE CONSUMER PRODUCT SAFETY ACT § 1145.17 Multi-purpose lighters that can be operated by children; risks of death or injury. (a) The Commission finds that it is in the public interest to regulate...

  14. WATER DISINFECTION PRACTICE

    DTIC Science & Technology

    The current review of canteen water disinfection proceeded along three general lines. A summary has been prepared of the information available from...the literature on canteen water disinfection. The current opinions of two outstanding investigators in the field of disinfection have been solicited in

  15. Solar water disinfection

    SciTech Connect

    Anderson, R.; Collier, R.

    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.

  16. Positive impact on heat loss and patient experience of preheated skin disinfection: a randomised controlled trial.

    PubMed

    Wistrand, Camilla; Söderquist, Bo; Nilsson, Ulrica

    2016-11-01

    The aim of this study was to compare the effect of preheated (36 °C) and room-temperature (20 °C) skin disinfectant solution on skin temperature and patients' experience of the skin disinfection process. To prevent surgical site infections, it is important to disinfect skin prior to invasive surgery. In clinical practice, conscious patients often comment on the coldness of the preoperative skin disinfection solution. Evidence is lacking, as to whether preheated skin disinfectant has any positive effects during preoperative skin disinfection. Randomised controlled trial. A total of 220 patients undergoing pacemaker, implantable cardioverter-defibrillator, or cardiac resynchronisation therapy under local anaesthesia were included and randomly allocated to preheated or room-temperature skin disinfection. Skin temperature was assessed before and after skin disinfection at the planned incision site; in addition, three study-specific questions were used to assess how patients experienced the temperature. Patients experienced the skin disinfection process with preheated disinfectant as significantly more pleasant. They felt less cold and reported increased satisfaction with the temperature of the solution compared to patients who were disinfected with room-temperature solution. Skin disinfection with preheated solution also yielded a significantly higher mean skin temperature compared to room-temperature solution. Preoperative skin disinfection with preheated disinfectant may prevent heat loss and contributes to a more pleasant experience for patients. Skin disinfection with preheated skin disinfectant is an easy and inexpensive nursing intervention that has a positive impact on heat loss and on patients' experience of the disinfection process. © 2016 John Wiley & Sons Ltd.

  17. Operation and maintenance of a new hazardous waste multi-purpose rotary kiln incinerator (system) in compliance with the Environmental Protection Agency and Louisiana (US) regulations

    SciTech Connect

    Fontenot, M.M. Jr.

    1997-12-31

    The proper management of hazardous and non-hazardous waste generated by modern society will continue to be a challenge for the world. Waste minimization and recycling practices will play a significant role in reducing the amount of waste to be managed. Total elimination of all waste in present day society is unlikely to occur in the future. Therefore, generators must take a proactive and responsible care approach to manage their wastes. An effective treatment operation to manage combustible waste is incineration. Properly designed, high efficiency waste incineration systems are very effective treatment solutions for waste management, particularly when compared to land disposal alternatives. High temperature incineration provides a permanent solution for destroying combustible waste and eliminate harmful or toxic organic constituents in the waste. The Novartis Crop Protection, Inc., St. Gabriel Facility, top environmental priority in the management of waste is to minimize waste at the source. The remaining wastes are recycled, detoxified, and/or incinerated. Land disposal of waste is the last resort for waste management. To achieve the St. Gabriel Facility waste management priorities, a new multi-purpose rotary kiln incinerator was constructed in 1992--93. The incinerator is the first of its kind constructed and permitted in the State of Louisiana since the promulgation of RCRA. The final operating conditions under RCRA were obtained from the regulatory agencies in 1996. This paper will discuss the operating and maintenance programs that were implemented for the new multi-purpose rotary kiln incinerator system to meet the RCRA permit conditions. A review of the preventative maintenance programs (i.e., equipment, monitors, analyzers), computer control, waste analysis, tracking of key parameters, operational cost and equipment reliability of the incinerator system will be presented.

  18. Friction Stir Weld Application and Tooling Design for the Multi-purpose Crew Vehicle Stage Adapter

    NASA Technical Reports Server (NTRS)

    Alcorn, John

    2013-01-01

    The Multi-Purpose Crew Vehicle (MPCV), commonly known as the Orion capsule, is planned to be the United States' next manned spacecraft for missions beyond low earth orbit. Following the cancellation of the Constellation program and creation of SLS (Space Launch System), the need arose for the MPCV to utilize the Delta IV Heavy rocket for a test launch scheduled for 2014 instead of the previously planned Ares I rocket. As a result, an adapter (MSA) must be used in conjunction with the MPCV to account for the variation in diameter of the launch vehicles; 5.5 meters down to 5.0 meters. Prior to ight article fabrication, a path nder (test article) will be fabricated to ne tune the associated manufacturing processes. The adapter will be comprised of an aluminum frustum (partial cone) that employs isogrid technology and circumferential rings on each end. The frustum will be fabricated by friction stir welding (FSW) three individual panels together on a Vertical Weld Tool (VWT) at NASA Marshall Space Flight Center. Subsequently, each circumferential ring will be friction stir welded to the frustum using a Robotic Weld Tool (RWT). The irregular geometry and large mass of the MSA require that extensive tooling preparation be put into support structures for the friction stir weld. The tooling on the VWT will be comprised of a set of conveyors mounted on pre-existing stanchions so that the MSA will have the ability to be rotated after each of the three friction stir welds. The tooling requirements to friction stir weld the rings with the RWT are somewhat more demanding. To support the mass of the MSA and resist the load of the weld tool, a system of mandrels will be mounted to stanchions and assembled in a circle. The goal of the paper will be to explain the design, fabrication, and assembly of the tooling, to explain the use of friction stir welding on the MSA path nder, and also to discuss the lessons learned and modi cations made in preparation for ight article fabrication

  19. A Multi-Purpose Data Dissemination Infrastructure for the Marine-Earth Observations

    NASA Astrophysics Data System (ADS)

    Hanafusa, Y.; Saito, H.; Kayo, M.; Suzuki, H.

    2015-12-01

    To open the data from a variety of observations, the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) has developed a multi-purpose data dissemination infrastructure. Although many observations have been made in the earth science, all the data are not opened completely. We think data centers may provide researchers with a universal data dissemination service which can handle various kinds of observation data with little effort. For this purpose JAMSTEC Data Management Office has developed the "Information Catalog Infrastructure System (Catalog System)". This is a kind of catalog management system which can create, renew and delete catalogs (= databases) and has following features, - The Catalog System does not depend on data types or granularity of data records. - By registering a new metadata schema to the system, a new database can be created on the same system without sytem modification. - As web pages are defined by the cascading style sheets, databases have different look and feel, and operability. - The Catalog System provides databases with basic search tools; search by text, selection from a category tree, and selection from a time line chart. - For domestic users it creates the Japanese and English pages at the same time and has dictionary to control terminology and proper noun. As of August 2015 JAMSTEC operates 7 databases on the Catalog System. We expect to transfer existing databases to this system, or create new databases on it. In comparison with a dedicated database developed for the specific dataset, the Catalog System is suitable for the dissemination of small datasets, with minimum cost. Metadata held in the catalogs may be transfered to other metadata schema to exchange global databases or portals. Examples: JAMSTEC Data Catalog: http://www.godac.jamstec.go.jp/catalog/data_catalog/metadataList?lang=enJAMSTEC Document Catalog: http://www.godac.jamstec.go.jp/catalog/doc_catalog/metadataList?lang=en&tab=categoryResearch Information

  20. NASA Planning for Orion Multi-Purpose Crew Vehicle Ground Operations

    NASA Technical Reports Server (NTRS)

    Letchworth, Gary; Schlierf, Roland

    2011-01-01

    tools included Kaizen/Lean events, mockups and human factors analysis. The majority of products developed by this team are applicable as KSC prepares 21st Century Ground Systems for the Orion Multi-Purpose Crew Vehicle and Space Launch System.

  1. Engineered Geophysical Disturbances, Geomorphic Processes, and Ecosystem Patterns in Large, Multi-purpose Rivers

    NASA Astrophysics Data System (ADS)

    Jacobson, R. B.

    2002-12-01

    Large rivers are used by society for a wide variety of goods and services; human impacts on these rivers are of a magnitude that they often can be considered geophysical disturbances. Engineered changes in many large, multi-purpose rivers can be categorized into semi-independent hydrologic and geomorphic components. Reservoir regulation is the dominant influence on the hydrologic component and bank stabilization/navigation structures comprise the dominant influence on the geomorphic component. Both components can have profound effects on temporal and spatial ecosystem patterns; on many rivers, the interaction of the two components is a critical issue in management and rehabilitation strategies. For example, engineered changes to the Lower Missouri River affect both hydrology (decreases in peak flows for flood control, increases in low flows to support navigation) and geomorphology (narrowing to create a self-scouring channel and bank stabilization to preserve farmland). Two-dimensional hydraulic modeling using pre- and post-engineered hydrologic times series and geomorphic boundary conditions document changes in ecosystem pattern measured as habitat diversity, habitat connectivity/fragmentation, and timing of habitat availability. The analysis points to rehabilitation strategies that may help to recover ecosystem patterns and functions. Channel engineering is a persistent disturbance that fundamentally alters how ecosystem patterns respond to subsequent, episodic geophysical disturbances. In the engineered Lower Missouri River, the energy of extreme floods is concentrated in discrete areas at levee breaks. Geomorphic processes at these sites are dominated by vertical erosion and deposition, resulting in a pattern of deep lentic scours ringed by sand splays, and separated by extensive tracts of unaltered farmland. In contrast, the pre-engineered channel responded to floods by migrating laterally. Relatively uniform lateral migration of bends resulted in long, sub

  2. Studies on egg disinfection.

    PubMed

    Adler, H E; DaMassa, A J; Scott, W F

    1979-07-01

    Various concentrations of alkyldimethylbenzyl ammonium chloride (QAC), Na2CO3, and ethylenediaminetetracetic acid (EDTA) were tested for antimicrobial activity singly and in combination against Escherichia coli, Arizona hinshawii, and Pseudomonas aeruginosa. Bactericidal activity of the reagents were evaluated in embryonating eggs, trypticase soy broth, and a medium containing lecithin. Toxicity of the chemicals was assayed in embryonating eggs. An appraisal was made of an egg-washing solution composed of 250 ppm QAC, 100 ppm Na2CO3, and 10 and 100 ppm EDTA. The mixture was effective and nontoxic for this purpose. All egg treatments had an adverse effect on fertility and hatchability. Using the temperature differential procedure in egg dipping, the disinfectant mixture was relatively nontoxic if 10 ppm EDTA was used with 3000 ppm tylosin tartrate. One hundred parts per million of the chelator in the dip solution caused excessive embryo mortality due to synergistic toxicity with the antibiotic. The germicidal action of the QAC solution was markedly increased with Na2CO3. Ten parts per million EDTA did not improve the biocidal effect of QAC solutions in distilled water but increased bactericidal activity in tap water that contained 16 ppm Ca and 22 ppm Mg.

  3. Moving Virtual Research Environments from high maintenance Stovepipes to Multi-purpose Sustainable Service-oriented Science Platforms

    NASA Astrophysics Data System (ADS)

    Klump, Jens; Fraser, Ryan; Wyborn, Lesley; Friedrich, Carsten; Squire, Geoffrey; Barker, Michelle; Moloney, Glenn

    2017-04-01

    The researcher of today is likely to be part of a team distributed over multiple sites that will access data from an external repository and then process the data on a public or private cloud or even on a large centralised supercomputer. They are increasingly likely to use a mixture of their own code, third party software and libraries, or even access global community codes. These components will be connected into a Virtual Research Environments (VREs) that will enable members of the research team who are not co-located to actively work together at various scales to share data, models, tools, software, workflows, best practices, infrastructures, etc. Many VRE's are built in isolation: designed to meet a specific research program with components tightly coupled and not capable of being repurposed for other use cases - they are becoming 'stovepipes'. The limited number of users of some VREs also means that the cost of maintenance per researcher can be unacceptably high. The alternative is to develop service-oriented Science Platforms that enable multiple communities to develop specialised solutions for specific research programs. The platforms can offer access to data, software tools and processing infrastructures (cloud, supercomputers) through globally distributed, interconnected modules. In Australia, the Virtual Geophysics Laboratory (VGL) was initially built to enable a specific set of researchers in government agencies access to specific data sets and a limited number of tools, that is now rapidly evolving into a multi-purpose Earth science platform with access to an increased variety of data, a broader range of tools, users from more sectors and a diversity of computational infrastructures. The expansion has been relatively easy, because of the architecture whereby data, tools and compute resources are loosely coupled via interfaces that are built on international standards and accessed as services wherever possible. In recent years, investments in

  4. Disinfection. [Wastewater treatment

    SciTech Connect

    Haas, C.N.; McCreary, J.J.

    1982-06-01

    Methods of disinfection of wastewater including chlorination, ultraviolet radiation, ozone, and quaternary compounds are reviewed. Various analytical methods to detect residues of the disinfectants are described. The production of inorganic and nonvolatile organic compounds in conventional water treatment processes is reviewed. (KRM)

  5. The Effect of Sodium Hypochlorite and Chlorhexidine as Irrigant Solutions for Root Canal Disinfection: A Systematic Review of Clinical Trials.

    PubMed

    Gonçalves, Lucio Souza; Rodrigues, Renata Costa Val; Andrade Junior, Carlos Vieira; Soares, Renata G; Vettore, Mario Vianna

    2016-04-01

    This systematic review aimed to compare the effectiveness of sodium hypochlorite and chlorhexidine for root canal disinfection during root canal therapy. A literature search for clinical trials was made on the PubMed (MEDLINE), Web of Knowledge, SCOPUS, and Science Direct databases and in the reference lists of the identified articles up to January 2015. Quality assessment of the selected studies was performed according to the Consolidated Standards of Reporting Trials statement. One clinical trial and 4 randomized clinical trials were selected from the 172 articles initially identified. There was heterogeneity in the laboratory methods used to assess the root canal disinfection as well as in the concentrations of the irrigants used. Therefore, meta-analysis was not performed. Two studies reported effective and similar reductions in bacterial levels for both irrigants. Sodium hypochlorite was more effective than chlorhexidine in reducing microorganisms in 1 study, and another reported opposite findings. Both root irrigants were ineffective in eliminating endotoxins from necrotic pulp root canals in 1 study. Trial design and information regarding randomization procedures were not clearly described in the clinical trials. No study compared laboratory results with clinical outcomes. The available evidence on this topic is scarce, and the findings of studies were not consistent. Additional randomized clinical trials using clinical outcomes to compare the use of sodium hypochlorite and chlorhexidine during root canal therapy are needed. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

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

    PubMed

    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.

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

    PubMed Central

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

    2016-01-01

    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. PMID:27399759

  8. [Spanish disinfectants for the 21st century].

    PubMed

    Herruzo Cabrera, R

    2000-01-01

    There are two chemical disinfectants patents from Spain that permit to obtain advantageous products on other disinfectants: Nduopropenide (two iodures of quaternary ammonium) and "Peroxidine" (hydrogen peroxide that active to lactic acid and a surfactant mixture). The first product is used as an antiseptic or disinfectant, but the second, only act as disinfectant. DISINFECTION: It is studied (by germ-carrier methods), the microbicide effect on different microorganisms (Gram positive cocci, Gram negative bacilli, fungus, Mycobacteria and B subtilis spores), comparing these two products with different disinfectants as 2% glutaraldehyde, 1/8 phenate-glutaraldehyde, peracetic acid compounds, 11% oxygen peroxide and 2% sodium hypoclorite. It is obtained that 1/4 Peroxidine in 5 minutes or 1/6 Peroxidine in 10 minutes, are the most effective disinfectant on all microorganisms used (includes the most resistant) since it produces destruction of 4 log-10 of spores and 5 log-10 of Mycobacteria. Moreover, it can destroy, completely, the inoculum of commercial spores, routinely used for sterilization process evaluation, in 20 minutes, when 2% glutaraldehyd needs 3-10 hours. ANTISEPSIE: It is studied the "hygienization" and surgical handwashing with Nduopropenide solution, in comparison with classical washing methods (neutral soap in routinely handwashing and 5% chlorhexidine or 10% iodine-povidone in surgical washing): 1) Nduopropenide and alcohol solution is more effective that routinely handwashing. 2) This product is more effective and persistent, after surgical washing that chlorhexidine or iodine-povidone. Moreover, it does not must be applied with brush. 3) The mixture Nduopropenide and chlorhexidine makes a synergy, then it can be used in hand or skin washing, on heath personnel or patient people, being advantageous on the other products.

  9. Managing runoff and flow pathways in a small rural catchment to reduce flood risk with other multi-purpose benefits

    NASA Astrophysics Data System (ADS)

    Wilkinson, Mark; Welton, Phil; Kerr, Peter; Quinn, Paul; Jonczyk, Jennine

    2010-05-01

    Belford only two houses were flooded. Data from the catchment and mitigation features showed that the defence measures resulted in an increase in travel time of the peak and attenuated high flows which would have usually travelled quickly down the channel to the village. For example, the pilot feature appears to have increased the travel time of a flood peak at the top of the catchment from 20 minutes to 35 minutes over a 1 km stretch of channel. There are currently ten active mitigation features present in the catchment. More features are planned for construction this year. Early data from the catchment indicates that the runoff attenuation features are having an impact on reducing flood flows in the channel and also slowing down the flood peak. At the same time the multi-purpose aspects of the features are apparent.

  10. Design and fabrication of a multi-purpose soft x-ray array diagnostic system for KSTAR

    SciTech Connect

    Lee, Seung Hun; Chai, Kil Byoung; Jang, Siwon; Choe, Wonho; Ko, Won-Ha; Kim, Junghee; Seo, Dongcheol; Lee, Jongha; Bogatu, I. N.; Kim, Jin-Soo

    2012-10-15

    A multi-purpose soft x-ray array diagnostic system was developed for measuring two-dimensional x-ray emissivity profile, electron temperature, Ar impurity transport, and total radiation power. A remotely controlled filter wheel was designed with three different choices of filters. The electron temperature profile can be determined from the ratio of two channels having different thickness of Be layer, and the Ar impurity concentration transport can be determined from a pair of Ar Ross filters (CaF{sub 2} and NaCl thin films). Without any filters, this diagnostic system can also be used as a bolometer.

  11. Effectiveness of commercial disinfectants for inactivating hepatitis A virus on agri-food surfaces.

    PubMed

    Jean, J; Vachon, J F; Moroni, O; Darveau, A; Kukavica-Ibrulj, I; Fliss, I

    2003-01-01

    Six commercial disinfectants were tested for their efficacy in inactivating hepatitis A virus in solution or attached to agri-food surfaces. Disinfectant I contains 10% quaternary ammonium plus 5% glutaraldehyde; disinfectant II contains 12% sodium hypochlorite; disinfectant III contains 2.9% dodecylbenzene sulfonic acid plus 16% phosphoric acid; disinfectant IV contains 10% quaternary ammonium; disinfectant V contains 2% iodide; and disinfectant VI contains 2% stabilized chlorine dioxide. Among these, disinfectants I and II were shown to be the most effective in inactivating hepatitis A virus in solution. The efficacy of these disinfectants was further tested against hepatitis A virus attached to common agri-food surfaces, including polyvinyl chlorine, high-density polyethylene, aluminum, stainless steel, and copper. Disinfectant II was shown to be the most effective, with a maximum inactivation level of about 3 log10. The inactivation efficacy was shown to be affected by the concentration of the active ingredient, the contact time between the disinfectant and the contaminated surfaces, and the incubation temperature. In general, hepatitis A virus was shown to be highly resistant to most disinfectants tested, and high concentrations of active ingredient were needed to achieve acceptable inactivation levels.

  12. A review of the developments of multi-purpose primers and adhesives comprising novel dithiooctanoate monomers and phosphonic acid monomers.

    PubMed

    Ikemura, Kunio; Endo, Takeshi; Kadoma, Yoshinori

    2012-02-03

    This paper reviews the developments of dithiooctanoate monomers and acidic adhesive monomers, and their roles in multi-purpose primers and adhesives in promoting adhesion to multiple substrate materials. Novel dithiooctanoate monomers exhibited excellent bonding to precious metals and alloys when compared against conventional sulfur-containing monomers. Newly developed phosphonic acid monomers, endowed with a water-soluble nature, enabled sufficient demineralization of dental hard tissues and thus improved bonding to both ground enamel and dentin. The optimal combination for bonding to dental hard tissues and precious and non-precious metals and alloys was 5.0 wt% 10-methacryloyloxydecyl 6,8-dithiooctanoate (10-MDDT) and 1.0 wt% 6-methacryloyloxyhexyl phosphonoacetate (6-MHPA). For bonding to dental porcelain, alumina, zirconia, and gold (Au) alloy, a ternary combination of silane coupling agent, acidic adhesive monomers, and dithiooctanoate monomers seemed promising. The latest development was a single-bottle, multi-purpose, self-etching adhesive which contained only acidic adhesive monomers and dithiooctanoate monomers but which produced strong adhesion to ground enamel and dentin, sandblasted zirconia, and Au alloy.

  13. A target field design of open multi-purpose RF coil for musculoskeletal MR imaging at 3T.

    PubMed

    Gao, Fei; Zhang, Rui; Zhou, Diange; Wang, Xiaoying; Huang, Kefu; Zhang, Jue

    2016-10-01

    Musculoskeletal MR imaging under multi-angle situations plays an increasingly important role in assessing joint and muscle tissues system. However, there are still limitations due to the closed structures of most conventional RF coils. In this study, a time-harmonic target-field method was employed to design open multi-purpose coil (OMC) for multi-angle musculoskeletal MR imaging. The phantom imaging results suggested that the proposed OMC could achieve homogeneously distributed magnetic field and high signal-to-noise ratio (SNR) of 239.04±0.83 in the region of interest (ROI). The maximum temperature in the heating hazard test was 16°C lower than the standard regulation, which indicated the security of the designed OMC. Furthermore, to demonstrate the effectiveness of the proposed OMC for musculoskeletal MR imaging, especially for multi-angle imaging, a healthy volunteer was examined for MR imaging of elbow, ankle and knee using OMC. The in vivo imaging results showed that the proposed OMC is effective for MR imaging of musculoskeletal tissues at different body parts, with satisfied B1 field homogeneity and SNR. Moreover, the open structure of the OMC could provide a large joint movement region. The proposed open multi-purpose coil is feasible for musculoskeletal MR imaging, and potentially, it is more suitable for the evaluation of musculoskeletal tissues under multi-angle conditions.

  14. Derivation of optimal joint operating rules for multi-purpose multi-reservoir water-supply system

    NASA Astrophysics Data System (ADS)

    Tan, Qiao-feng; Wang, Xu; Wang, Hao; Wang, Chao; Lei, Xiao-hui; Xiong, Yi-song; Zhang, Wei

    2017-08-01

    The derivation of joint operating policy is a challenging task for a multi-purpose multi-reservoir system. This study proposed an aggregation-decomposition model to guide the joint operation of multi-purpose multi-reservoir system, including: (1) an aggregated model based on the improved hedging rule to ensure the long-term water-supply operating benefit; (2) a decomposed model to allocate the limited release to individual reservoirs for the purpose of maximizing the total profit of the facing period; and (3) a double-layer simulation-based optimization model to obtain the optimal time-varying hedging rules using the non-dominated sorting genetic algorithm II, whose objectives were to minimize maximum water deficit and maximize water supply reliability. The water-supply system of Li River in Guangxi Province, China, was selected for the case study. The results show that the operating policy proposed in this study is better than conventional operating rules and aggregated standard operating policy for both water supply and hydropower generation due to the use of hedging mechanism and effective coordination among multiple objectives.

  15. A multi-purpose system for water purification and sea-water softening.

    PubMed

    Barsky, L; Rubinstein, J; Barsky, S; Kirzhner, F; Bodul, O

    1998-01-01

    A novel technique that can be used for reacting toxic carbon dioxide (CO2) emissions from power plants and other combustion wastes with sea water is described. A chemical interaction between CO2 and the cations in sea water, with the pH electrolytically regulated, can precipitate almost all the calcium and magnesium ions, as well as some sodium and potassium ions, as carbonates and bicarbonates. The carbonates and bicarbonates thus prepared can then be mixed with ash to yield a building material. Sulfur ions will be neutralized with calcium and magnesium, and the remaining ions can be removed using reverse osmosis or some other method. The technology and equipment for purification are based on modules that can be used for industrial waste-water, sea water, solutions, and otherwise. The module for separation of sand and suspended coarse substances consists of a tank for flocculation, coagulation, and precipitation of solid particles; and a low-pressure hydrocyclone. The module for purification from oil and fine suspensions is based on column flotation, flotation with a special ejector, and adhesion flotation. The module for ions and colloids consists of an absorbing filter with zeolite, fly ash, and other absorbing materials. Using a laboratory model consisting of a special mini-plant, we processed 10 L of factory-waste water containing more than 20 g/L organic content (compare with the upper limit of 0.02 g/L allowed by the Ministry of Environmental Protection in Israel). After the experimental solution was treated and evaporated to a small bulk, the water obtained was almost clear. On the basis of the results in the model, we present a scaled-up process for the design, development, and production of equipment for and the assembly of a large installation for drainage and water purification.

  16. Humidifier disinfectants, unfinished stories.

    PubMed

    Choi, Yeyong; Paek, Domyung

    2016-01-01

    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.

  17. Disinfectants to Fight Oral Candida Biofilms.

    PubMed

    Rodrigues, M Elisa; Henriques, Mariana; Silva, Sónia

    Oral biofilms, especially those caused by oral mycobiota, which include Candida species, are very difficult to eradicate, due to their complex structure and recalcitrance. Moreover, the mouth is prone to be colonized since it presents different types of surfaces, especially biomaterials and dental implants, often associated with a high rate of infections. Therefore, although disinfection of the oral cavity is of major importance, the number of commercially available disinfectants is not high. However, new solutions, as silver nanoparticles are being developed to help oral biofilms' eradication.

  18. Short-term Operation of Multi-purpose Reservoir using Model Predictive Control

    NASA Astrophysics Data System (ADS)

    Uysal, Gokcen; Schwanenberg, Dirk; Alvarado Montero, Rodolfo; Sensoy, Aynur; Arda Sorman, Ali

    2017-04-01

    Operation of water structures especially with conflicting water supply and flood mitigation objectives is under more stress attributed to growing water demand and changing hydro-climatic conditions. Model Predictive Control (MPC) based optimal control solutions has been successfully applied to different water resources applications. In this study, Feedback Control (FBC) and MPC get combined and an improved joint optimization-simulation operating scheme is proposed. Water supply and flood control objectives are fulfilled by incorporating the long term water supply objectives into a time-dependent variable guide curve policy whereas the extreme floods are attenuated by means of short-term optimization based on MPC. A final experiment is carried out to assess the lead time performance and reliability of forecasts in a hindcasting experiment with imperfect, perturbed forecasts. The framework is tested in Yuvacık Dam reservoir where the main water supply reservoir of Kocaeli City in the northwestern part of Turkey (the Marmara region) and it requires a challenging gate operation due to restricted downstream flow conditions.

  19. Multi-purpose HealthCare Telemedicine Systems with mobile communication link support

    PubMed Central

    Kyriacou, E; Pavlopoulos, S; Berler, A; Neophytou, M; Bourka, A; Georgoulas, A; Anagnostaki, A; Karayiannis, D; Schizas, C; Pattichis, C; Andreou, A; Koutsouris, D

    2003-01-01

    The provision of effective emergency telemedicine and home monitoring solutions are the major fields of interest discussed in this study. Ambulances, Rural Health Centers (RHC) or other remote health location such as Ships navigating in wide seas are common examples of possible emergency sites, while critical care telemetry and telemedicine home follow-ups are important issues of telemonitoring. In order to support the above different growing application fields we created a combined real-time and store and forward facility that consists of a base unit and a telemedicine (mobile) unit. This integrated system: can be used when handling emergency cases in ambulances, RHC or ships by using a mobile telemedicine unit at the emergency site and a base unit at the hospital-expert's site, enhances intensive health care provision by giving a mobile base unit to the ICU doctor while the telemedicine unit remains at the ICU patient site and enables home telemonitoring, by installing the telemedicine unit at the patient's home while the base unit remains at the physician's office or hospital. The system allows the transmission of vital biosignals (3–12 lead ECG, SPO2, NIBP, IBP, Temp) and still images of the patient. The transmission is performed through GSM mobile telecommunication network, through satellite links (where GSM is not available) or through Plain Old Telephony Systems (POTS) where available. Using this device a specialist doctor can telematically "move" to the patient's site and instruct unspecialized personnel when handling an emergency or telemonitoring case. Due to the need of storing and archiving of all data interchanged during the telemedicine sessions, we have equipped the consultation site with a multimedia database able to store and manage the data collected by the system. The performance of the system has been technically tested over several telecommunication means; in addition the system has been clinically validated in three different countries using

  20. Disinfection of laryngoscopes: A survey of practice

    PubMed Central

    Chaskar, Vaishali Prabhakar; Dave, Nandini Malay; Dias, Raylene; Karnik, Priyanka

    2017-01-01

    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. PMID:28405039

  1. Development and applications of a multi-purpose digital controller with a System-on-Chip FPGA for accelerators

    NASA Astrophysics Data System (ADS)

    Kurimoto, Yoshinori; Nakamura, Keigo

    2016-12-01

    J-PARC Main Ring (MR) is a high intensity proton synchrotron which accelerates protons from 3 GeV to 30 GeV. It has operated at a beam intensity of 390 kW and an upgrade toward the megawatt rating is scheduled. For higher beam intensity, some of the accelerator components require more intelligent and complicated functions. To consolidate such functions among various components, we developed multi-purpose digital boards using a System-on-Chip Field-Programmable Gated Array (SoC FPGA). In this paper, we describe the details of our developed boards as well as their possible applications. As an application of the boards, we have successfully performed the measurement of the betatron amplitude function during beam acceleration in J-PARC MR. The experimental setup and results of the measurement are also described in detail.

  2. Low cost multi-purpose balloon-borne platform for wide-field imaging and video observation

    NASA Astrophysics Data System (ADS)

    Ocaña, Francisco; Sánchez de Miguel, Alejandro; Conde, Aitor

    2016-07-01

    Atmosphere layers, especially the troposphere, hinder the astronomical observation. For more than 100 years astronomers have tried observing from balloons to avoid turbulence and extinction. New developments in cardsize computers, RF equipment and satellite navigation have democratised the access to the stratosphere. As a result of a ProAm collaboration with the Daedalus Team we have developed a low-cost multi-purpose platform with stratospheric balloons carrying up to 3 kg of scientific payload. The Daedalus Team is an amateur group that has been launching sounding probes since 2010. Since then the first two authors have provided scienti fic payloads for nighttime flights with the purpose of technology demonstration for astronomical observation. We have successfully observed meteor showers (Geminids 2012, Camelopardalis 2014, Quadrantids 2016 and Lyrids 2016) and city light pollution emission with image and video sensors covering the 400-1000nm range.

  3. Orion Multi-Purpose Crew Vehicle Active Thermal Control and Environmental Control and Life Support Development Status

    NASA Technical Reports Server (NTRS)

    Lewis, John F.; Barido, Richard A.; Boehm, Paul; Cross, Cynthia D.; Rains, George Edward

    2014-01-01

    The Orion Multi Purpose Crew Vehicle (MPCV) is the first crew transport vehicle to be developed by the National Aeronautics and Space Administration (NASA) in the last thirty years. Orion is currently being developed to transport the crew safely beyond Earth orbit. This year, the vehicle focused on building the Exploration Flight Test 1 (EFT1) vehicle to be launched in September of 2014. The development of the Orion Active Thermal Control (ATCS) and Environmental Control and Life Support (ECLS) System, focused on the integrating the components into the EFT1 vehicle and preparing them for launch. Work also has started on preliminary design reviews for the manned vehicle. Additional development work is underway to keep the remaining component progressing towards implementation on the flight tests of EM1 in 2017 and of EM2 in 2020. This paper covers the Orion ECLS development from April 2013 to April 2014.

  4. Orion Multi-Purpose Crew Vehicle Active Thermal Control and Environmental Control and Life Support Development Status

    NASA Technical Reports Server (NTRS)

    Lewis, John F.; Barido, Richard A.; Cross, Cynthia D.; Rains, George Edward

    2013-01-01

    The Orion Multi-Purpose Crew Vehicle (MPCV) is the first crew transport vehicle to be developed by the National Aeronautics and Space Administration (NASA) in the last thirty years. Orion is currently being developed to transport the crew safely beyond Earth orbit. This year, the vehicle focused on building the Exploration Flight Test 1 (EFT1) vehicle to be launched in 2014. The development of the Orion Environmental Control and Life Support (ECLS) System, focused on the completing the components which are on EFT1. Additional development work has been done to keep the remaining component progressing towards implementation for a flight tests in of EM1 in 2017 and in and EM2 in 2020. This paper covers the Orion ECLS development from April 2012 to April 2013.

  5. Liftoff and Time Equivalent Duration Data Evaluation of Exploration Flight Test 1 Orion Multi-Purpose Crew Vehicle

    NASA Technical Reports Server (NTRS)

    Houston, Janice

    2016-01-01

    The liftoff phase induces high acoustic loading over a broad frequency range for a launch vehicle. These external acoustic environments are used in the prediction of the internal vibration responses of the vehicle and components. There arises the question about time equivalent (Teq) duration of the liftoff phase and similarity to other launch vehicles. Vibroacoustic engineers require the fatigue-weighted time duration values for qualification testing inputs. In order to determine the Teq for the Space Launch System, NASA's newest launch vehicle, the external microphone data from the Exploration Flight Test 1 (EFT-1) flight of the Orion Multi-Purpose Crew Vehicle (MPCV) was evaluated. During that evaluation, a trend was observed in the data and the origin of that trend is discussed in this paper. Finally, the Teq values for the EFT-1 Orion MPCV are presented.

  6. K/FAST - The U.S. Army's NDI multi-purpose Ku-band fly-away Satcom terminal

    NASA Astrophysics Data System (ADS)

    Kelly, Alexander J.; Bernard, Robert A.; Stevens, Peter E.; D'Alessandro, Maryann

    1992-03-01

    Attention is given to K/FAST, a NDI multi-purpose Ku-band fly-away Satcom terminal, and the ways in which it epitomizes current trends in military C3I. K/FAST is a state-of-the-art, all solid-state Ku-band terminal providing medium data rate (less than T1) capability. It is designed to accept a GFE bulk encryptor, and includes a multiplexer subsystem with plug-in jacks for secure or nonsecure phones. The multiplexer is reconfigurable, in the field, and permits a mix of compressed voice, data, facsimile, and compressed video. It is demonstrated that off-the-shelf state-of-the-art NDI hardware can be integrated to meet military mission requirements while bypassing the typical multiyear DOD research-and-development cycle.

  7. Environmental assessment for the reuse of TNX as a multi-purpose pilot plant campus at the Savannah River Site

    SciTech Connect

    1998-07-01

    The Department of Energy (DOE) prepared this environmental assessment (EA) to analyze the potential environmental and safety impacts of DOE planning to allow asset reuse of the TNX Area at the Savannah River Site (SRS) located near Aiken, South Carolina. The proposed action would include providing for a location for the Centers of Excellence at or adjacent to SRS and entering into a cooperative agreement with a non-profit management and operations (management firm) contractor to operate and market the TNX facilities and equipment. The area (formerly TNX) would be called a Multi-Purpose Pilot Plant Campus (MPPC) and would be used: (1) as location for technology research, development, demonstration, and commercial operations; (2) to establish partnerships with industry to develop applied technologies for commercialization; and (3) serve as administrative headquarters for Centers of Excellence in the program areas of soil remediation, radioecology, groundwater contamination, and municipal solid waste minimization.

  8. Urban photogrammetric data base for multi-purpose cadastral-based information systems: the Riyadh city case

    NASA Astrophysics Data System (ADS)

    Al-garni, Abdullah M.

    Urban information systems are economic resources that can benefit decision makers in the planning, development, and management of urban projects and resources. In this research, a conceptual model-based prototype Urban Geographic Information System (UGIS) is developed. The base maps used in developing the system and acquiring visual attributes are obtained from aerial photographs. The system is a multi-purpose parcel-based one that can serve many urban applications such as public utilities, health centres, schools, population estimation, road engineering and maintenance, and many others. A modern region in the capital city of Saudi Arabia is used for the study. The developed model is operational for one urban application (population estimation) and is tested for that particular application. The results showed that the system has a satisfactory accuracy and that it may well be promising for other similar urban applications in countries with similar demographic and social characteristics.

  9. The effect of a range of disinfectants on the dimensional accuracy of some impression materials.

    PubMed

    Jagger, D C; Al Jabra, O; Harrison, A; Vowles, R W; McNally, L

    2004-12-01

    In this study the dimensional accuracy of two model materials; dental stone and plaster of Paris, reproduced from three commonly used impression materials; alginate, polyether and addition-cured silicone, retained by their adhesives in acrylic resin trays and exposed to four disinfectant solutions was evaluated. Ninety casts were used to investigate the effect of the four disinfectants on the dimensional accuracy of alginate, polyether and addition-cured silicone impression material. For each impression material 30 impressions were taken, half were poured in dental stone and half in plaster of Paris. The disinfectants used were Dimenol, Perform-ID, MD-520, and Haz-tabs. Measurements were carried out using a High Precision Reflex Microscope. For the alginate impressions only those disinfected by 5-minute immersion in Haz-tabs solution and in full-strength MD 520 were not adversely affected by the disinfection treatment. All polyether impressions subjected to immersion disinfection exhibited a clinically acceptable expansion. Disinfected addition-cured silicone impressions produced very accurate stone casts. Those disinfected by spraying with fill-strength Dimenol produced casts that were very similar to those left as controls, but those treated by immersion disinfection exhibited negligible and clinically acceptable expansion. The results of the studied demonstrated that the various disinfection treatments had different effects on the impression materials. It is important that an appropriate disinfectant is used for each type of impression material.

  10. Optimum Disinfection Properties and Commercially Available Disinfectants

    DTIC Science & Technology

    1989-07-01

    and its oyproducts have been negative (25). Sodium dichloro-s-triaztnetrione, also known as sodium dichloroisocyanurate , is the only promising...Candidates Criterion Chlorine dioxide Sodium dichloro-s- triazinetrione * Health effects : toxicity of chemical and byproducts less than HTH no more than...necesary and identify by block number) FIELD GROUP SU -GROUP :potable water, disinfectant; chlorine dioxide; sodium dichloro-s-triazinetrione, 3-Chloro-4,4

  11. Microbial contamination and disinfection methods of pacifiers

    PubMed Central

    NELSON, Paulo; LOUVAIN, Márcia Costa; MACARI, Soraia; LUCISANO, Marília Pacífico; da SILVA, Raquel Assed Bezerra; de QUEIROZ, Alexandra Mussolino; GATON-HERNÁNDEZ, Patrícia; da SILVA, Léa Assed Bezerra

    2015-01-01

    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®). PMID:26537723

  12. Microbial contamination and disinfection methods of pacifiers.

    PubMed

    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 (p<0.05). The analysis of SEM showed the formation of a cariogenic biofilm in all groups with positive culture. 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).

  13. Overcoming the problem of residual microbial contamination in dental suction units left by conventional disinfection using novel single component suction handpieces in combination with automated flood disinfection.

    PubMed

    Boyle, M A; O'Donnell, M J; Russell, R J; Galvin, N; Swan, J; Coleman, D C

    2015-10-01

    cannot be adequately disinfected without disassembly, which is costly in time, staff and resources. The automated STCS DCU suction disinfection system used with single component handpieces provides an effective solution. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Emergency Disinfection of Drinking Water

    EPA Pesticide Factsheets

    How to boil and disinfect water to kill most disease-causing microorganisms during emergency situations where regular water service has been interrupted and local authorities recommend using only bottled water, boiled water, or disinfected water.

  15. Effective reprocessing of reusable dispensers for surface disinfection tissues – the devil is in the details

    PubMed Central

    Kampf, Günter; Degenhardt, Stina; Lackner, Sibylle; Ostermeyer, Christiane

    2014-01-01

    Background: It has recently been reported that reusable dispensers for surface disinfection tissues may be contaminated, especially with adapted Achromobacter species 3, when products based on surface-active ingredients are used. Fresh solution may quickly become recontaminated if dispensers are not processed adequately. Methods: We evaluated the abilities of six manual and three automatic processes for processing contaminated dispensers to prevent recolonisation of a freshly-prepared disinfectant solution (Mikrobac forte 0.5%). Dispensers were left at room temperature for 28 days. Samples of the disinfectant solution were taken every 7 days and assessed quantitatively for bacterial contamination. Results: All automatic procedures prevented recolonisation of the disinfectant solution when a temperature of 60–70°C was ensured for at least 5 min, with or without the addition of chemical cleaning agents. Manual procedures prevented recontamination of the disinfectant solution when rinsing with hot water or a thorough cleaning step was performed before treating all surfaces with an alcohol-based disinfectant or an oxygen-releaser. Other cleaning and disinfection procedures, including the use of an alcohol-based disinfectant, did not prevent recolonisation. Conclusions: These results indicate that not all processes are effective for processing reusable dispensers for surface-disinfectant tissues, and that a high temperature during the cleaning step or use of a biofilm-active cleaning agent are essential. PMID:24653973

  16. Multi-purpose silastic dual-lumen central venous catheters for both collection and transplantation of hematopoietic progenitor cells.

    PubMed

    Lazarus, H M; Trehan, S; Miller, R; Fox, R M; Creger, R J; Raaf, J H

    2000-04-01

    Autologous peripheral blood progenitor cell (PBPC) transplantation frequently requires sequential placement and use of two separate central venous catheters: (1) a short-term, large-bore, stiff device inserted for leukapheresis, and after removal of that device, (2) a long-term, multi-lumen, flexible, Silastic catheter for administration of high-dose chemotherapy, re-infusion of hematopoietic cells, and intensive supportive care. We reviewed our recent experience with two dual-lumen, large-bore, Silastic multi-purpose ('hybrid') catheters, each of which can be used as a single device for both leukapheresis and long-term supportive care throughout the transplant process. Quinton-Raaf PermCath and Bard-Hickman hemodialysis/apheresis dual-lumen catheters were used as the sole venous access device in 112 consecutive patients who underwent autologous PBPC collection and transplantation. The catheter exit site was monitored three times a week, and lumen patency was assessed using clinical and radiologic techniques. Catheters were removed prematurely for persistent thrombus, positive blood cultures despite appropriate antibiotics, or mechanical dysfunction. There were no intra-operative or immediate post-operative complications relating to insertion. Thirty-two patients experienced catheter occlusion necessitating urokinase instillation. Persistent occlusive problems were noted in 16 patients, and in 10 patients the catheter had to be removed. Two exit site infections and 17 bacteremias occurred. Catheters had to be removed for persistent infection in two subjects and for mechanical problems in five others. Cost analysis comparing the hybrid catheters alone vs conventional devices revealed a charge of $4230 in patients with hybrid catheters vs. $7530 in those requiring a temporary non-Silastic dialysis catheter in addition to a flexible, long-term Silastic catheter. Hybrid, Silastic, dual-lumen, large-bore central venous catheters are safe, cost-effective and convenient

  17. Effect of disinfectant agents on dimensional stability of elastomeric impression materials.

    PubMed

    Adabo, G L; Zanarotti, E; Fonseca, R G; Cruz, C A

    1999-05-01

    Difficulties in sterilizing impressions by traditional methods have led to chemical disinfection as an alternative, and some studies have shown that disinfectants may adversely affect impressions. This study investigated the effect of disinfection methods on the dimensional stability of 6 elastomeric materials. Impression materials were submitted to the following treatments: immersion in 5.25% sodium hypochlorite solution for 10 minutes, immersion in 2% glutaraldehyde solution for 30 minutes, and no immersion (control). After treatments, impressions were poured, and respective stone casts were measured with a Nikon Profile projector and compared with the master model. The elastomeric materials had different reproduction capacities, and the disinfecting treatments did not differ from the control.

  18. Ortho-phthalaldehyde exposure levels among endoscope disinfection workers.

    PubMed

    Miyajima, Keiko; Yoshida, Jin; Kumagai, Shinji

    2010-01-01

    Recently, the use of ortho-phthalaldehyde (OPA) has been increasing as an alternative to glutaraldehyde for endoscope disinfection. To better understand OPA exposure and its health effects among disinfection workers, we conducted environmental monitoring and administered a questionnaire in 17 endoscope disinfection rooms. There were 9 manual disinfection rooms using immersion vats for scope disinfection and 8 automatic rooms using automatic washers. OPA exposure concentration during the disinfection process of scope was significantly higher in the manual group (median: 1.43ppb, range: not detected (ND-5.37ppb) than in the automatic group (median: 0.35 ppb, range: ND-0.69 ppb). Similarly, during charging and discharging the antiseptic solution, OPA levels were significantly higher in the manual group (median: 2.58 ppb, range: 0.92-10.0 ppb) than in the automatic group (median: 0.46ppb, range: ND-1.35 ppb). Time-weighted averages of OPA exposure concentration during work shifts were 0.33 to 1.15 ppb (median 0.66 ppb) in the manual group and 0.13 to 1.28 ppb (median 0.33 ppb) in the automatic group, which suggests that manual workers are exposed to OPA at higher levels. Among 80 female disinfection workers who used only antiseptic solutions containing OPA, the incidence of disinfection-related complaints were 10% skin, 9% eye, and 16% respiratory symptoms. These findings suggest that it is desirable to introduce automatic washers to decrease OPA exposure levels among disinfection workers.

  19. Poorly processed reusable surface disinfection tissue dispensers may be a source of infection

    PubMed Central

    2014-01-01

    Background Reusable surface disinfectant tissue dispensers are used in hospitals in many countries because they allow immediate access to pre-soaked tissues for targeted surface decontamination. On the other hand disinfectant solutions with some active ingredients may get contaminated and cause outbreaks. We determined the frequency of contaminated surface disinfectant solutions in reusable dispensers and the ability of isolates to multiply in different formulations. Methods Reusable tissue dispensers with different surface disinfectants were randomly collected from healthcare facilities. Solutions were investigated for bacterial contamination. The efficacy of two surface disinfectants was determined in suspension tests against two isolated species directly from a contaminated solution or after 5 passages without selection pressure in triplicate. Freshly prepared use solutions were contaminated to determine survival of isolates. Results 66 dispensers containing disinfectant solutions with surface-active ingredients were collected in 15 healthcare facilities. 28 dispensers from nine healthcare facilities were contaminated with approximately 107 cells per mL of Achromobacter species 3 (9 hospitals), Achromobacter xylosoxidans or Serratia marcescens (1 hospital each). In none of the hospitals dispenser processing had been adequately performed. Isolates regained susceptibility to the disinfectants after five passages without selection pressure but were still able to multiply in different formulations from different manufacturers at room temperature within 7 days. Conclusions Neglecting adequate processing of surface disinfectant dispensers has contributed to frequent and heavy contamination of use-solutions based on surface active ingredients. Tissue dispenser processing should be taken seriously in clinical practice. PMID:24447780

  20. Poorly processed reusable surface disinfection tissue dispensers may be a source of infection.

    PubMed

    Kampf, Günter; Degenhardt, Stina; Lackner, Sibylle; Jesse, Katrin; von Baum, Heike; Ostermeyer, Christiane

    2014-01-21

    Reusable surface disinfectant tissue dispensers are used in hospitals in many countries because they allow immediate access to pre-soaked tissues for targeted surface decontamination. On the other hand disinfectant solutions with some active ingredients may get contaminated and cause outbreaks. We determined the frequency of contaminated surface disinfectant solutions in reusable dispensers and the ability of isolates to multiply in different formulations. Reusable tissue dispensers with different surface disinfectants were randomly collected from healthcare facilities. Solutions were investigated for bacterial contamination. The efficacy of two surface disinfectants was determined in suspension tests against two isolated species directly from a contaminated solution or after 5 passages without selection pressure in triplicate. Freshly prepared use solutions were contaminated to determine survival of isolates. 66 dispensers containing disinfectant solutions with surface-active ingredients were collected in 15 healthcare facilities. 28 dispensers from nine healthcare facilities were contaminated with approximately 107 cells per mL of Achromobacter species 3 (9 hospitals), Achromobacter xylosoxidans or Serratia marcescens (1 hospital each). In none of the hospitals dispenser processing had been adequately performed. Isolates regained susceptibility to the disinfectants after five passages without selection pressure but were still able to multiply in different formulations from different manufacturers at room temperature within 7 days. Neglecting adequate processing of surface disinfectant dispensers has contributed to frequent and heavy contamination of use-solutions based on surface active ingredients. Tissue dispenser processing should be taken seriously in clinical practice.

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

    PubMed

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

    2013-01-01

    , it is recommended that water disinfection should never be compromised by attempting to control DBPs. The reason for this is that the risks of human illness and death from pathogens in drinking water are much greater than the risks from exposure to disinfectants and disinfection by-products. Nevertheless, if DBP levels exceed regulatory limits, strategies should focus on eliminating organic impurities that foster their formation, without compromising disinfection. As alternatives to chlorine, disinfectants such as chloramines, ozone, chlorine dioxide, and UV disinfection are gaining popularity. Chlorine and each of these disinfectants have individual advantage and disadvantage in terms of cost, efficacy-stability, ease of application, and nature of disinfectant by-products (DBPs). Based on efficiency, ozone is the most efficient disinfectant for inactivating bacteria, viruses, and protozoa. In contrast, chloramines are the least efficient and are not recommended for use as primary disinfectants. Chloramines are favored for secondary water disinfection, because they react more slowly than chlorine and are more persistent in distribution systems. In addition, chloramines produce lower DBP levels than does chlorine, although microbial activity in the distribution system may produce nitrate from monochloramine, when it is used as a residual disinfectant, Achieving the required levels of water quality, particularly microbial inactivation levels, while minimizing DBP formation requires the application of proper risk and disinfection management protocols. In addition, the failure of conventional treatment processes to eliminate critical waterborne pathogens in drinking water demand that improved and/or new disinfection technologies be developed. Recent research has disclosed that nanotechnology may offer solutions in this area, through the use of nanosorbents, nanocatalysts, bioactive nanoparticles, nanostructured catalytic membranes, and nanoparticle-enhanced filtration.

  2. Iodine Tagging Velocimetry and Mechanism in the Hypersonic Near Wake of a MultiPurpose Crew Vehicle

    NASA Technical Reports Server (NTRS)

    Balla, R. Jeffrey

    2013-01-01

    This study demonstrates a new molecular tagging velocimetry (MTV) method for velocity measurements of high speed flow. It demonstrates offbody Iodine Tagging Velocimetry (ITV) in the hypersonic near wake of a MultiPurpose Crew Vehicle (MPCV) model. Experiments are performed in the NASA-Langley 31-inch Mach 10 air wind tunnel. A 0.5% I2 / N2 mixture is seeded on the leeward backshell of the model using a pressure tap. I2 laser-induced fluorescence is excited along a 5.5 mm line using an ArF excimer laser near 193 nm. Results indicate I2 absorbs at least 2 photons to produce iodine ions and electrons. These recombine as the tagged region is displaced downstream to produce I (2P3/2) whose emission is monitored at 206 nm. Results at P0 = 2.41 MPa (350 psi), T0 = 990K, and 10 micro-sec transit times produce velocities from 630-820 m/sec across the I2 seeded jet at a distance of 38.2 mm (25.5 jet diameters) downstream from the jet orifice. Maximum wake jet velocities near the shear layer are 59% of freestream velocity.

  3. Genetic algorithms optimization of hedging rules for operation of the multi-purpose Ubonratana Reservoir in Thailand

    NASA Astrophysics Data System (ADS)

    Chiamsathit, C.; Adeloye, A. J.; Soudharajan, B.

    2014-09-01

    This study has developed optimal hedging policies for the multi-purpose Ubonratana Reservoir in northeastern Thailand based on its existing rule curves. The hedging policy was applied whenever the reservoir storage falls below a critical level for each month of the year. The decision variables, i.e. the set of monthly storages defining the critical rule curve that triggers rationing and the rationing ratio, were optimized by genetic algorithm (GA). Both single stage (i.e. with one critical rule curve and one rationing ratio) and two-stage (with two critical rule curves and ratios) of the hedging policy were considered in the optimization. To test the effect of the optimized hedging policies on reservoir performance, simulations were carried out, forced alternatively with the existing rule curves (i.e. without hedging) and the two optimized hedging policies. Performance was summarized in terms of reliability (time- and volume-based) and vulnerability. The results showed that the vulnerability was significantly reduced by using the optimized hedging rules. However, the number of water shortages increased with the optimized rules, causing the time-based reliability to worsen significantly. This should not be of concern since, although the number of shortages increased, the associated shortage quantities on most of these additional occasions were small, leaving the volumetric reliability largely unchanged.

  4. A randomised, single-blind comparison of high-level disinfectants for flexible nasendoscopes.

    PubMed

    Hitchcock, B; Moynan, S; Frampton, C; Reuther, R; Gilling, P; Rowe, F

    2016-11-01

    To compare the microbiological efficacy, turnaround time, cost, convenience, and patient and user tolerance of Tristel Trio Wipes, PeraSafe solution and Cidex OPA solution for the high-level disinfection of flexible nasendoscopes. Flexible nasendoscopes were used in routine clinical encounters. They were then disinfected with one of the three disinfectant methods. Surveillance cultures were taken before and after each disinfection process. Data relating to each of the study parameters were recorded. Positive bacterial cultures were discovered on nasendoscopes disinfected with PeraSafe and Cidex OPA. Tristel Trio Wipes have no capital outlay cost, the lowest running cost, the greatest convenience and the fastest turnaround time. PeraSafe had a faster turnaround time than Cidex OPA, and lower running costs. Tristel Trio Wipes are equal to PeraSafe and Cidex OPA in terms of microbiological efficacy. Turnaround time and cost are dramatically reduced when using Tristel Trio Wipes compared to the other disinfectant methods.

  5. Effect of microwave disinfection on denture base adaptation and resin surface roughness.

    PubMed

    Sartori, Evandro Afonso; Schmidt, Caroline Bom; Walber, Luiz Fernando; Shinkai, Rosemary Sadami Arai

    2006-01-01

    This study evaluated the effect of disinfection methods [chemical disinfection (immersion in 100 ppm chloride solution) or microwave disinfection (690 W for 6 min)] on the internal adaptation of denture bases and resin surface roughness. For the adaptation test, 18 maxillary denture bases were obtained from stone casts duplicated from a metallic master model and submitted to the following treatments: 1) control (no disinfection), 2) chemical disinfection or 3) microwave disinfection. Disinfection procedures were performed twice (T1, T2) with a 7-day interval between them. Internal adaptation was measured at baseline (T0) and after T1 and T2 by weighing a vinyl polysiloxane film reproducing the gap between the resin base and the master model. For surface roughness measurement, 60 rectangular (5x10x40 mm) resin specimens were either mechanically or chemically polished and then submitted to the disinfection treatments. Surface roughness (Ra) was recorded after polishing (T0) and after T1 and T2. Data were analyzed by ANOVA GLM for repeated measures and Bonferroni correction at 5% significance level. Bases submitted to microwave disinfection had gradual increase of misfit, while bases immersed in chloride solution did not differ from the control group. Surface roughness increased in the mechanical polishing groups with microwave disinfection and decreased in the chemical polishing groups.

  6. Cytotoxicity assessment of residual high-level disinfectants.

    PubMed

    Ryu, Mizuyuki; Kobayashi, Toshihiro; Kawamukai, Emiko; Quan, Glenlelyn; Furuta, Taro

    2013-01-01

    Some studies show the uptake of disinfectants on medical devices but no studies on their cytotoxicity have been reported. This study aimed to assess that cytotoxicity in a 3-dimensional culture system using HeLa cells grown in matrices composed of collagen. Plastic materials were soaked in the use solutions of the widely used high-level disinfectants, glutaraldehyde (GA), ortho-phthalaldehyde (OPA) and peracetic acid (PAA). After being rinsed, they were allowed to dry and were embedded into the cell medium to investigate the cytotoxicity of the residual disinfectants. Cytotoxicity was observed with the polyvinyl chloride, polyurethane and silicon tubes soaked in GA and OPA, indicating that both disinfectants were absorbed in the test pieces, whereas for PAA, none was observed. As for the polytetrafluoroethylene (PTFE) tubes, no disinfectant displayed cytotoxicity. GA and OPA are primary irritants, having a potential to cause anaphylaxis and other forms of allergic reactions. There should be consideration not only about the toxicity of the residual disinfectant from poor rinsing, but also about the toxicity that would result from the disinfectants that were absorbed and consequently released from the medical devices or materials.

  7. In vitro study on the disinfectability of two split-septum needle-free connection devices using different disinfection procedures.

    PubMed

    Engelhart, Steffen; Exner, Martin; Simon, Arne

    2015-01-01

    This in vitro study investigated the external disinfection of two needle-free connection devices (NFC) using Octeniderm(®) (spraying and wiping technique) vs. Descoderm(®) pads (wiping technique). The split-septum membrane of the NFC was contaminated with >10(5) CFU K. pneumoniae or S. epidermidis. The efficacy of the disinfection at 30 sec. exposure time was controlled by taking a swab sample and by flushing the NFC with sterile 0.9% sodium chloride solution. Disinfection with octenidine dihydrochloride 0.1 g, 1-Propanol 30.0 g, and 2-Propanol 45.0 g in 100 g solution was highly effective (CFU reduction ≥4 log) against both microorganisms, whereas the use of 63.1 g 2-Propanol in 100 ml solution led to residual contamination with S. epidermidis. Our investigation underlines that (i) in clinical practice disinfection of NFCs before use is mandatory, and that (ii) details of disinfection technique are of utmost importance regarding their efficacy. Our investigation revealed no significant differences between both split-septum NFC types. Clinical studies are needed to confirm a possible superiority of disinfectants with long-lasting residual antimicrobial activity.

  8. In vitro study on the disinfectability of two split-septum needle-free connection devices using different disinfection procedures

    PubMed Central

    Engelhart, Steffen; Exner, Martin; Simon, Arne

    2015-01-01

    This in vitro study investigated the external disinfection of two needle-free connection devices (NFC) using Octeniderm® (spraying and wiping technique) vs. Descoderm® pads (wiping technique). The split-septum membrane of the NFC was contaminated with >105 CFU K. pneumoniae or S. epidermidis. The efficacy of the disinfection at 30 sec. exposure time was controlled by taking a swab sample and by flushing the NFC with sterile 0.9% sodium chloride solution. Disinfection with octenidine dihydrochloride 0.1 g, 1-Propanol 30.0 g, and 2-Propanol 45.0 g in 100 g solution was highly effective (CFU reduction ≥4 log) against both microorganisms, whereas the use of 63.1 g 2-Propanol in 100 ml solution led to residual contamination with S. epidermidis. Our investigation underlines that (i) in clinical practice disinfection of NFCs before use is mandatory, and that (ii) details of disinfection technique are of utmost importance regarding their efficacy. Our investigation revealed no significant differences between both split-septum NFC types. Clinical studies are needed to confirm a possible superiority of disinfectants with long-lasting residual antimicrobial activity. PMID:26693394

  9. In vitro-in vivo sequence studies as a method of selecting the most efficacious alcohol-based solution for hygienic hand disinfection.

    PubMed

    Herruzo, R; Vizcaino, M J; Herruzo, I

    2010-05-01

    The use of alcohol-based hand rubs serves to reduce hospital-acquired infections. Many products of this type are now on offer and it is essential to know how to rank their efficacy. A sequence of tests is proposed here to compare any given new alcohol-based solution against the reference solution (60% 2-isopropyl-alcohol) with 30 s of contact time: (i) in vitro (with pig skin as carrier) testing of >30 species of microorganism; (ii) in vitro assessment of residual efficacy (after 30 min of drying); (iii) in vivo study of transient microbiota (modification of the EN 1500 standard procedure) using four ATCC strains; (iv) in vivo study of resident hand microbiota. After performing the in vitro evaluation of seven alcohol-based hand rubs, the two most efficacious (chlorhexidine-quac-alcohol and mecetronium- alcohol) were chosen and studied, comparatively with the reference solution (60% isopropyl alcohol), in vitro (for chemical sustainability on the skin) and in vivo (against transient and resident microbiota). Chlorhexidine-quac-alcohol proved to be significantly superior to mecetronium-alcohol or the reference solution in all tests, except against resident microbiota for which the improvement was not statistically significant.

  10. [Optimizing surgical hand disinfection].

    PubMed

    Kampf, G; Kramer, A; Rotter, M; Widmer, A

    2006-08-01

    For more than 110 years hands of surgeons have been treated before a surgical procedure in order to reduce the bacterial density. The kind and duration of treatment, however, has changed significantly over time. Recent scientific evidence suggests a few changes with the aim to optimize both the efficacy and the dermal tolerance. Aim of this article is the presentation and discussion of new insights in surgical hand disinfection. A hand wash should be performed before the first disinfection of a day, ideally at least 10 min before the beginning of the disinfection as it has been shown that a 1 min hand wash significantly increases skin hydration for up to 10 min. The application time may be as short as 1.5 min depending on the type of hand rub. Hands and forearms should be kept wet with the hand rub for the recommended application time in any case. A specific rub-in procedure according to EN 12791 has been found to be suitable in order to avoid untreated skin areas. The alcohol-based hand rub should have a proven excellent dermal tolerance in order to ensure appropriate compliance. Considering these elements in clinical practice can have a significant impact to optimize the high quality of surgical hand disinfection for prevention of surgical site infections.

  11. CHLORINE DISINFECTION OF AEROMONAS

    EPA Science Inventory

    The bacterial genus Aeromonas is currently listed on the USEPA's Candidate Contaminant List (CCL). Resistance to chemical disinfection is an essential aspect regarding all microbial groups listed on the CCL. This study was designed to determine the inactivation kinetics of Aeromo...

  12. CHLORINE DISINFECTION OF AEROMONAS

    EPA Science Inventory

    The bacterial genus Aeromonas is currently listed on the USEPA's Candidate Contaminant List (CCL). Resistance to chemical disinfection is an essential aspect regarding all microbial groups listed on the CCL. This study was designed to determine the inactivation kinetics of Aeromo...

  13. Use of Hydrogen Peroxide to Disinfect Hydroponic Plant Growth Systems

    NASA Technical Reports Server (NTRS)

    Barta, Daniel J.; Henderson, Keith

    2000-01-01

    Hydrogen peroxide was studied as an alternative to conventional bleach and rinsing methods to disinfect hydroponic plant growth systems. A concentration of 0.5% hydrogen peroxide was found to be effective. Residual hydrogen peroxide can be removed from the system by repeated rinsing or by flowing the solution through a platinum on aluminum catalyst. Microbial populations were reduced to near zero immediately after treatment but returned to pre-disinfection levels 2 days after treatment. Treating nutrient solution with hydrogen peroxide and planting directly into trays being watered with the nutrient solution without replenishment, was found to be detrimental to lettuce germination and growth.

  14. Sporicidal activity of hospital disinfectants

    PubMed Central

    Kelsey, J. C.; Mackinnon, I. H.; Maurer, Isobel M.

    1974-01-01

    The sporicidal activity of hospital disinfectants was tested using two methods of test and two species of spores. Alcoholic hypochlorite and glutaraldehyde (Cidex) showed some sporicidal activity; the first was the more effective. Iodophors, formalin, and phenolics were less effective, in descending order. Chlorhexidine showed no activity. A freshly prepared solution containing 50% methanol and sufficient sodium hypochlorite to provide 2000 parts per million available chlorine in distilled water, with a contact time of 15 minutes, is suggested for the decontamination of clean, heat-sensitive instruments except those of plated metal. It must be understood that no such method can be depended upon to sterilize. The instruments should be rinsed in sterile water before use after decontamination. PMID:4213961

  15. Multi-time scale Climate Informed Stochastic Hybrid Simulation-Optimization Model (McISH model) for Multi-Purpose Reservoir System

    NASA Astrophysics Data System (ADS)

    Lu, M.; Lall, U.

    2013-12-01

    In order to mitigate the impacts of climate change, proactive management strategies to operate reservoirs and dams are needed. A multi-time scale climate informed stochastic model is developed to optimize the operations for a multi-purpose single reservoir by simulating decadal, interannual, seasonal and sub-seasonal variability. We apply the model to a setting motivated by the largest multi-purpose dam in N. India, the Bhakhra reservoir on the Sutlej River, a tributary of the Indus. This leads to a focus on timing and amplitude of the flows for the monsoon and snowmelt periods. The flow simulations are constrained by multiple sources of historical data and GCM future projections, that are being developed through a NSF funded project titled 'Decadal Prediction and Stochastic Simulation of Hydroclimate Over Monsoon Asia'. The model presented is a multilevel, nonlinear programming model that aims to optimize the reservoir operating policy on a decadal horizon and the operation strategy on an updated annual basis. The model is hierarchical, in terms of having a structure that two optimization models designated for different time scales are nested as a matryoshka doll. The two optimization models have similar mathematical formulations with some modifications to meet the constraints within that time frame. The first level of the model is designated to provide optimization solution for policy makers to determine contracted annual releases to different uses with a prescribed reliability; the second level is a within-the-period (e.g., year) operation optimization scheme that allocates the contracted annual releases on a subperiod (e.g. monthly) basis, with additional benefit for extra release and penalty for failure. The model maximizes the net benefit of irrigation, hydropower generation and flood control in each of the periods. The model design thus facilitates the consistent application of weather and climate forecasts to improve operations of reservoir systems. The

  16. Effects of disinfectants in renal dialysis patients

    SciTech Connect

    Klein, E.

    1986-11-01

    Patients receiving hemodialysis therapy risk exposure to both disinfectants and sterilants. Dialysis equipment is disinfected periodically with strong solutions of hypochlorite or formaldehyde. Gross hemolysis resulting from accidental hypochlorite infusion has led to cardiac arrest, probably as a result of hyperkalemia. Formaldehyde is commonly used in 4% solutions to sterilize the fluid paths of dialysis controllers and to sterilize dialyzers before reuse. It can react with red cell antigenic surfaces leading to the formation of anti-N antibodies. The major exposure risk is the low concentration of disinfectant found in municipal water used to prepare 450 L dialysate weekly. With thrice-weekly treatment schedules, the quality requirements for water used to make this solution must be met rigorously. Standards for water used in the preparation of dialysate have recently been proposed but not all patients are treated with dialysate meeting such standards. The introduction of sterilants via tap water is insidious and has let to more pervasive consequences. Both chlorine and chloramines, at concentrations found in potable water, are strong oxidants that cause extensive protein denaturation and hemolysis. Oxidation of the Fe/sup 2 +/ in hemoglobin to Fe/sup 3 +/ forms methemoglobin, which is incapable of carrying either O/sub 2/ or CO/sub 2/. Chloramine can form not only methemoglobin, but can also denature proteins within the red cell, thus forming aggregates (Heinz bodies). Chloramines also inhibit hexose monophosphate shunt activity, a mechanism that makes the red cell even more susceptible to oxidant damage.

  17. Resistance of Pseudomonas aeruginosa Isolates to Hydrogel Contact Lens Disinfection Correlates with Cytotoxic Activity

    PubMed Central

    Lakkis, Carol; Fleiszig, Suzanne M. J.

    2001-01-01

    One of the most common pathogens in infection of hydrogel contact lens wearers is Pseudomonas aeruginosa, which can gain access to the eye via contamination of the lens, lens case, and lens care solutions. Only one strain per species is used in current regulatory testing for the marketing of chemical contact lens disinfectants. The aim of this study was to determine whether P. aeruginosa strains vary in their susceptibility to hydrogel contact lens disinfectants. A method for rapidly screening bacterial susceptibility to contact lens disinfectants was developed, based on measurement of the MIC. The susceptibility of 35 P. aeruginosa isolates to two chemical disinfectants was found to vary among strains. MICs ranged from 6.25 to 100% for both disinfectants at 37°C, and a number of strains were not inhibited by a 100% disinfectant concentration in the lens case environment at room temperature (22°C). Resistance to disinfection appeared to be an inherent rather than acquired trait, since some resistant strains had been isolated prior to the introduction of the disinfectants and some susceptible P. aeruginosa strains could not be made more resistant by repeated disinfectant exposure. A number of P. aeruginosa strains which were comparatively more resistant to short-term disinfectant exposure also demonstrated the ability to grow to levels above the initial inoculum in one chemical disinfectant after long-term (24 to 48 h) disinfectant exposure. Resistance was correlated with acute cytotoxic activity toward corneal epithelial cells and with exsA, which encodes a protein that regulates cytotoxicity via a complex type III secretion system. These results suggest that chemical disinfection solutions may select for contamination with cytotoxic strains. Further investigation of the mechanisms and factors responsible for resistance may also lead to strategies for reducing adverse responses to contact lens wear. PMID:11283074

  18. Disinfection of bacterially contaminated hydrophilic PVS impression materials.

    PubMed

    Estafanous, Emad Wadie; Palenik, Charles John; Platt, Jeffrey A

    2012-01-01

    This study evaluated disinfection of bacterially contaminated hydrophilic polyvinylsiloxane (PVS) and polyether impressions. Four light-bodied PVS (Examix, Genie, Take 1, Aquasil) and one polyether (Impregum) impression materials were evaluated using three disinfectants (EcoTru [EnviroSystems], ProSpray [Certol], and bleach [diluted 1:9]) as spray and immersion disinfections for 10-minute exposures. Pseudomonas aeruginosa ATCC 15442, Salmonella choleraesius ATCC 10708, and Staphylococcus aureus ATCC 6538 was the microbial challenge. Test specimens were prepared using aluminum molds with ten tapered cones. Mucin covered each cone, followed by 0.01 mL of each bacterium. Impressions were made using low viscosity impression material that was injected over the cones and filled custom trays. One-half of the impressions were spray disinfected, while the others underwent immersion disinfection. Trays that were contaminated but not disinfected served as positive controls, while those not bacterially contaminated or disinfected served as negative controls. The impressions were poured with Silky Rock Die Stone, and after setting, two cones were placed within a sterile capsule and triturated into powder. Four milliliters of TRIS buffer (0.05 M, pH 7.0) containing sodium thiosulfate (0.0055% w/v) were poured in each tube. After mixing, the solution was serially diluted and spread-plated onto selective agars. After incubation, colony counting occurred. No viable bacteria transferred to casts from either spray- or immersion-disinfected impressions. Negative controls produced no microbial colonies. Positive controls produced on average 3.35 × 10(5) bacterial cells. Results suggest the methods used could disinfect contaminated impression materials. Microbial transfer from nondisinfected impressions to cones approached 33.5%. © 2011 by the American College of Prosthodontists.

  19. Determining effective forecast horizons for multi-purpose reservoirs with short- and long-term operating objectives

    NASA Astrophysics Data System (ADS)

    Luchner, Jakob; Anghileri, Daniela; Castelletti, Andrea

    2017-04-01

    Real-time control of multi-purpose reservoirs can benefit significantly from hydro-meteorological forecast products. Because of their reliability, the most used forecasts range on time scales from hours to few days and are suitable for short-term operation targets such as flood control. In recent years, hydro-meteorological forecasts have become more accurate and reliable on longer time scales, which are more relevant to long-term reservoir operation targets such as water supply. While the forecast quality of such products has been studied extensively, the forecast value, i.e. the operational effectiveness of using forecasts to support water management, has been only relatively explored. It is comparatively easy to identify the most effective forecasting information needed to design reservoir operation rules for flood control but it is not straightforward to identify which forecast variable and lead time is needed to define effective hedging rules for operational targets with slow dynamics such as water supply. The task is even more complex when multiple targets, with diverse slow and fast dynamics, are considered at the same time. In these cases, the relative importance of different pieces of information, e.g. magnitude and timing of peak flow rate and accumulated inflow on different time lags, may vary depending on the season or the hydrological conditions. In this work, we analyze the relationship between operational forecast value and streamflow forecast horizon for different multi-purpose reservoir trade-offs. We use the Information Selection and Assessment (ISA) framework to identify the most effective forecast variables and horizons for informing multi-objective reservoir operation over short- and long-term temporal scales. The ISA framework is an automatic iterative procedure to discriminate the information with the highest potential to improve multi-objective reservoir operating performance. Forecast variables and horizons are selected using a feature

  20. Investigating a multi-purpose target for electron linac based photoneutron sources for BNCT of deep-seated tumors

    NASA Astrophysics Data System (ADS)

    Masoudi, S. Farhad; Rasouli, Fatemeh S.

    2015-08-01

    Recent studies in BNCT have focused on investigating appropriate neutron sources as alternatives for nuclear reactors. As the most prominent facilities, the electron linac based photoneutron sources benefit from two consecutive reactions, (e, γ) and (γ, n). The photoneutron sources designed so far are composed of bipartite targets which involve practical problems and are far from the objective of achieving an optimized neutron source. This simulation study deals with designing a compact, optimized, and geometrically simple target for a photoneutron source based on an electron linac. Based on a set of MCNPX simulations, tungsten is found to have the potential of utilizing as both photon converter and photoneutron target. Besides, it is shown that an optimized dimension for such a target slows-down the produced neutrons toward the desired energy range while keeping them economy, which makes achieving the recommended criteria for BNCT of deep-tumors more available. This multi-purpose target does not involve complicated designing, and can be considered as a significant step toward finding application of photoneutron sources for in-hospital treatments. In order to shape the neutron beam emitted from such a target, the beam is planned to pass through an optimized arrangement of materials composed of moderators, filters, reflector, and collimator. By assessment with the recommended in-air parameters, it is shown that the designed beam provides high intensity of desired neutrons, as well as low background contamination. The last section of this study is devoted to investigate the performance of the resultant beam in deep tissue. A typical simulated liver tumor, located within a phantom of human body, was subjected to the irradiation of the designed spectrum. The dosimetric results, including evaluated depth-dose curves and carried out in-phantom parameters show that the proposed configuration establishes acceptable agreement between the appropriate neutron intensity, and

  1. Monte Carlo simulations of gamma-ray space telescopes: a BoGEMMS multi-purpose application

    NASA Astrophysics Data System (ADS)

    Fioretti, Valentina; Bulgarelli, Andrea; Tavani, Marco; Marisaldi, Martino; Sabatini, Sabina; Malaguti, Giuseppe; Trifoglio, Massimo; Gianotti, Fulvio

    2014-07-01

    After the development of a BoGEMMS (Bologna Geant4 Multi-Mission Simulator) template for the background study of X-ray telescopes, a new extension is built for the simulation of a Gamma-ray space mission (e.g. AGILE, Fermi), conceived to work as a common, multi-purpose framework for the present and future electron tracking gamma-ray space telescopes. The Gamma-ray extension involves the Geant4 mass model, the physics list and, more important, the production and treatment of the simulation output. From the user point of view, the simulation set-up follows a tree structure, with the main level being the selection of the simulation framework (the general, X-ray or gamma-ray application) and the secondary levels being the detailed configuration of the geometry and the output format. The BoGEMMS application to Gamma-ray missions has been used to evaluate the instrument performances of a new generation of Gamma-ray telescopes (e.g. Gamma-Light), and a full simulation of the AGILE mission is currently under construction, to scientifically validate and calibrate the simulator with real in-space data sets. A complete description of the BoGEMMS Gamma-ray framework is presented here, with an overview of the achieved results for the potential application to present and future experiments (e.g., GAMMA-400 and Gamma-Light). The evaluation of the photon conversion efficiency to beta particle pairs and the comparison to tabulated data allows the preliminary physical validation of the overall architecture. The Gamma-ray module application for the study of the Gamma-Light instrument performances is reported as reference test case.

  2. Status of the effectiveness of contact lens disinfectants in Malaysia against keratitis-causing pathogens.

    PubMed

    Abjani, Farhat; Khan, Naveed Ahmed; Jung, Suk Yul; Siddiqui, Ruqaiyyah

    2017-09-15

    The aim of this study was (i) to assess the antimicrobial effects of contact lens disinfecting solutions marketed in Malaysia against common bacterial eye pathogens and as well as eye parasite, Acanthamoeba castellanii, and (ii) to determine whether targeting cyst wall would improve the efficacy of contact lens disinfectants. Using ISO 14729 Stand-Alone Test for disinfecting solutions, bactericidal and amoebicidal assays of six different contact lens solutions including Oxysept(®), AO SEPT PLUS, OPTI-FREE(®) pure moist(®), Renu(®) fresh™, FreshKon(®) CLEAR and COMPLETE RevitaLens™ were performed using Manufacturers Minimum recommended disinfection time (MRDT). The efficacy of contact lens solutions was determined against keratitis-causing microbes, namely: Pseudomonas aeruginosa, Methicillin-resistant Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, and Acanthamoeba castellanii. In addition, using chlorhexidine as an antiamoebic compound and cellulase enzyme to disrupt cyst wall structure, we determined whether combination of both agents can enhance efficacy of marketed contact lens disinfectants against A. castellanii trophozoites and cysts, in vitro. The results revealed that all contact lens disinfectants tested showed potent bactericidal effects exhibiting 100% kill against all bacterial species tested. In contrast, none of the contact lens disinfectants had potent effects against Acanthamoeba cysts viability. When tested against trophozoites, two disinfectants, Oxysept Multipurpose and AO-sept Multipurpose showed partial amoebicidal effects. Using chlorhexidine as an antiamoebic compound and cellulase enzyme to disrupt cyst wall structure, the findings revealed that combination of both agents in contact lens disinfectants abolished viability of A. castellanii cysts and trophozoites. Given the inefficacy of contact lens disinfectants tested in this study, these findings present a significant concern to public health. These

  3. Hardness of heat-polymerized acrylic resins after disinfection and long-term water immersion.

    PubMed

    Neppelenbroek, Karin Hermana; Pavarina, Ana Cláudia; Vergani, Carlos Eduardo; Giampaolo, Eunice Teresinha

    2005-02-01

    In selecting a disinfectant for dental prostheses, compatibility between the disinfectant and the type of denture base material must be considered to avoid adverse effects on the hardness of the acrylic resin. This study investigated the hardness of 2 denture base resins after disinfection and long-term water immersion. Thirty-two disk-shaped specimens (13 mm in diameter and 8 mm thick) were fabricated from each resin (Lucitone 550 and QC-20), polished, stored in water at 37 degrees C for 48 hours, and submitted to hardness tests (Vickers hardness number [VHN]) before disinfection. Disinfection methods included scrubbing with 4% chlorhexidine gluconate for 1 minute, immersion for 10 minutes in 1 of the tested disinfectant solutions (n=8) (3.78% sodium perborate, 4% chlorhexidine gluconate, or 1% sodium hypochorite), and immersion in water for 3 minutes. The disinfection procedures were repeated 4 times, and 12 hardness measurements were made on each specimen. Control specimens (not disinfected) were stored in water for 56 minutes. Hardness tests (VHN) were also performed after 15, 30, 60, 90, and 120 days of storage in water. Statistical analyses of data were conducted with a repeated measures 3-way analysis of variance (ANOVA) and Tukey post-hoc test (alpha=.05). Mean values +/- SD for Lucitone 550 (16.52 +/- 0.94 VHN) and QC-20 (9.61 +/- 0.62 VHN) demonstrated a significant (P <.05) decrease in hardness after disinfection, regardless of material and disinfectant solutions used (Lucitone 550: 15.25 +/- 0.74; QC-20: 8.09 +/- 0.39). However, this effect was reversed after 15 days of storage in water. Both materials exhibited a continuous increase (P <.05) in hardness values for up to 60 days of water storage, after which no significant change was observed. Within the limitations of this in vitro study, QC-20 and Lucitone 550 specimens exhibited significantly lower hardness values after disinfection regardless of the disinfectant solution used.

  4. The higher disinfectant resistance of nosocomial isolates of Klebsiella oxytoca: how reliable are indicator organisms in disinfectant testing?

    PubMed

    Gebel, J; Sonntag, H-G; Werner, H-P; Vacata, V; Exner, M; Kistemann, T

    2002-04-01

    The Children's Clinic in Giessen, Germany recently reported several severe infections with Klebsiella oxytoca resulting in deaths of two neonates. The putative source of the infections was a contaminated infusion solution. The resistance to disinfectant of the K. oxytoca isolates was investigated in three independent laboratories and was indeed found to be significantly increased. Comparative tests with standard strains of K. oxytoca and other recommended bacterial surrogates showed the disinfection procedures used were fully effective. The higher resistance of the nosocomial isolates may have developed due to improper handling and storage of the cleaning utensils. This report describes the events and draws conclusions concerning the use of disinfectants, the treatment of cleaning utensils, the reliability of procedures for testing disinfectants, and suggests additional measures.

  5. Commercial Disinfectants During Disinfection Process Validation: More Failures than Success

    PubMed Central

    Chumber, Sushil Kumar; Khanduri, Uma

    2016-01-01

    Introduction Disinfection process validation is mandatory before introduction of a new disinfectant in hospital services. Commercial disinfection brands often question existing hospital policy claiming greater efficacy and lack of toxicity of their products. Inadvertent inadequate disinfection leads to morbidity, patient’s economic burden, and the risk of mortality. Aim To evaluate commercial disinfectants for high, intermediate and low-level disinfection so as to identify utility for our routine situations. Materials and Methods This laboratory based experiment was conducted at St Stephen Hospital, Delhi during July-September 2013. Twelve commercial disinfectants: Sanidex®, Sanocid®, Cidex®, SekuSept Aktiv®, BIB Forte®, Alprojet W®, Desnet®, Sanihygiene®, Incidin®, D125®, Lonzagard®, and Glutishield® were tested. Time-kill assay (suspension test) was performed against six indicator bacteria (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella Typhi, Bacillus cereus, and Mycobacterium fortuitum). Low and high inoculum (final concentrations 1.5X106 and 9X106 cfu/ml) of the first five bacteria while only low level of M. fortuitum was tested. Results Cidex® (2.4% Glutaraldehyde) performed best as high level disinfectant while newer quarternary ammonium compounds (QACs) (Incidin®, D125®, and Lonzagard®) were good at low level disinfection. Sanidex® (0.55% Ortho-pthalaldehyde) though mycobactericidal took 10 minutes for sporicidal activity. Older QAC containing BIB Forte® and Desnet® took 20 minutes to fully inhibit P. aeruginosa. All disinfectants effectively reduced S. Typhi to zero counts within 5 minutes. Conclusion Cidex® is a good high-level disinfectant while newer QACs (Incidin®, D125®, and Lonzagard®) were capable low-level disinfectants. PMID:27656441

  6. Cytotoxicity, interaction with dentine and efficacy on multispecies biofilms of a modified salt solution intended for endodontic disinfection in a new in vitro biofilm model.

    PubMed

    van der Waal, S V; Scheres, N; de Soet, J J; Wesselink, P R; Crielaard, W

    2015-02-01

    To investigate the cytotoxicity of a modified salt solution (MSS) and evaluate the antimicrobial properties of MSS on in vitro biofilm models. In a metabolic assay, fibroblasts derived from periodontal ligaments (PDL) of human extracted teeth were cultured and challenged with MSS or controls. Then, in active attachment biofilm models, the efficacy of MSS in the presence of dentine powder and in eliminating mature biofilms was investigated. In the dentine assay, a biofilm of Enterococcus faecalis was employed. For the final assay, microorganisms were retrieved from infected root canals and cultured to produce biofilms. After the treatments with MSS or the controls, the biofilms were collected, serially diluted and plated. The colony-forming units were counted. One-way anova was used to analyse the differences between the groups. A P < 0.05 was considered significant. The PDL fibroblasts remained metabolically active after challenges with MSS. Dentine powder did not alter the efficacy of MSS (P > 0.05). In endodontic biofilms, the culturable bacteria were equally reduced by MSS, 2% chlorhexidine (CHX) or 2% sodium hypochlorite (NaOCl) (P > 0.05). Modified salt solution is noncytotoxic in vitro and has good antimicrobial properties equal to CHX and NaOCl. Although the results are promising, ex vivo and in vivo studies are needed before its use as an interappointment root canal dressing can be considered. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  7. The effect of immersion disinfection procedures on dimensional stability of two elastomeric impression materials.

    PubMed

    Melilli, Dario; Rallo, Antonio; Cassaro, Angelo; Pizzo, Giuseppe

    2008-12-01

    The aim of this study was to determine the effect of immersion disinfection procedures on the dimensional stability of two elastomeric impression materials. Impressions of a stainless steel die were made with polyether (PE) and with addition-polymerized silicone rubber (PVS). The test specimens underwent disinfection treatment by immersion in two commercially available solutions containing quaternary ammonium compounds (Sterigum Powder, SP) and glutaraldehyde plus an amino derivative (MD520, MD), respectively. The impressions were measured at 4 different time points: before any disinfection treatment (T0); after the first disinfection (T1); 6 hours after the first disinfection (T2); after the second disinfection, carried out 6 hours after the first one (T3). Impressions which were not disinfected served as controls. When both impression materials were disinfected with SP, significant differences were detected among all measurements (P < 0.0001), with the exception of T2 vs T3 (P > 0.05). On the other hand, when MD was used, significant differences were found when T0 measurement was compared to T1, T2 and T3 measurements (P = 0.0043 for PE, and P = 0.0014 for PVS). The dimensional change of all material/disinfectant combinations was always disinfection on the dimension of elastomers in SP or MD are not clinically relevant.

  8. Impact of virus aggregation on inactivation by peracetic acid and implications for other disinfectants.

    PubMed

    Mattle, Michael J; Crouzy, Benoit; Brennecke, Moritz; Wigginton, Krista R; Perona, Paolo; Kohn, Tamar

    2011-09-15

    Viruses in wastewater and natural environments are often present as aggregates. The disinfectant dose required for their inactivation, however, is typically determined with dispersed viruses. This study investigates how aggregation affects virus inactivation by chemical disinfectants. Bacteriophage MS2 was aggregated by lowering the solution pH, and aggregates were inactivated by peracetic acid (PAA). Aggregates were redispersed before enumeration to obtain the residual number of individual infectious viruses. In contrast to enumerating whole aggregates, this approach allowed an assessment of disinfection efficiency which remains applicable even if the aggregates disperse in post-treatment environments. Inactivation kinetics were determined as a function of aggregate size (dispersed, 0.55 and 0.90 μm radius) and PAA concentration (5-103 mg/L). Aggregation reduced the apparent inactivation rate constants 2-6 fold. The larger the aggregate and the higher the PAA concentration, the more pronounced the inhibitory effect of aggregation on disinfection. A reaction-diffusion based model was developed to interpret the experimental results, and to predict inactivation rates for additional aggregate sizes and disinfectants. The model showed that the inhibitory effect of aggregation arises from consumption of the disinfectant within the aggregate, but that diffusion of the disinfectant into the aggregates is not a rate-limiting factor. Aggregation therefore has a large inhibitory effect if highly reactive disinfectants are used, whereas inactivation by mild disinfectants is less affected. Our results suggest that mild disinfectants should be used for the treatment of water containing viral aggregates.

  9. Mechanisms of actions of sodium hypochlorite in cleaning and disinfection processes.

    PubMed

    Fukuzaki, Satoshi

    2006-12-01

    Sodium hypochlorite (NaOCl) is the most widely used disinfectant in the food industry despite the increasing availability of other disinfectants. Sodium hypochlorite fulfills many requirements as the ideal disinfectant and furthermore it has an excellent cleaning action. The effectiveness of sodium hypochlorite in the cleaning and disinfection processes depends on the concentration of available chlorine and the pH of the solution. Hypochlorous acid (HOCl) is a weak acid and dissociates to the hypochlorite ion (-OCl) and proton (H+) depending on the solution pH. It is generally believed that HOCl is the active species in the germicidal action, whereas the concentration of -OCl is a key factor determining the cleaning efficiency. This implies that the optimal pH region of the germicidal activity of sodium hypochlorite differs from that of its cleaning activity. This paper describes the theory and practice of the cleaning and disinfecting operations based on the use of sodium hypochlorite solution.

  10. Bacterial Contamination of a Phenolic Disinfectant

    PubMed Central

    Simmons, N. A.; Gardner, D. A.

    1969-01-01

    Twenty ward stock bottles of aqueous 1% Printol were examined and 17 were found to be contaminated with Alcaligenes faecalis. Organisms were present in dead space behind the plastic liners of the bottle caps, where they could have survived washing. A. faecalis was also isolated from 31 out of 34 1% Printol solutions in use in the hospital. Pseudomonas aeruginosa was grown from two samples of 1% Printol in one ward, but not from stock bottles. The minimal bactericidal concentration (M.B.C.) in aqueous solution of Hycolin, Sudol, and Stericol for A. faecalis and Ps. aeruginosa was 1 in 320. The M.B.C. of Printol for both organisms was 1 in 80. The activity of all four disinfectants was reduced in the presence of large amounts of organic matter. Sudol was the least affected. Polyethylene, of which stock bottles were made, did not reduce the activity of the disinfectants. It is suggested that, ideally, stock bottles of disinfectant diluted ready for use should be autoclaved before they are refilled. PMID:4977328

  11. 9 CFR 96.13 - Uncertified casings; disinfection with hydrochloric acid.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... hydrochloric acid. 96.13 Section 96.13 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Uncertified casings; disinfection with hydrochloric acid. Foreign animal casings offered for importation into...) Disinfect the casings in a solution made as follows: Dissolve 90 pounds common salt in 100 gallons water and...

  12. 9 CFR 91.18 - Cleaning and disinfection of transport carriers for export.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Cleaning and disinfection of transport....18 Cleaning and disinfection of transport carriers for export. All fittings, utensils and equipment... prepared solution of: (a) Sodium carbonate (4 percent) in the proportion of 1 pound to 3 gallons of...

  13. 9 CFR 91.18 - Cleaning and disinfection of transport carriers for export.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Cleaning and disinfection of transport....18 Cleaning and disinfection of transport carriers for export. All fittings, utensils and equipment... prepared solution of: (a) Sodium carbonate (4 percent) in the proportion of 1 pound to 3 gallons of...

  14. Comparison of disinfectant efficacy when using high-volume directed mist application of accelerated hydrogen peroxide and peroxymonosulfate disinfectants in a large animal hospital.

    PubMed

    Saklou, N T; Burgess, B A; Van Metre, D C; Hornig, K J; Morley, P S; Byers, S R

    2016-07-01

    Effective decontamination of animal holding environments is critical for providing high quality patient care and maintaining a safe working environment. Disinfection of animal holding environments is a significant challenge during times of epidemic disease. The purpose of this study was to evaluate the disinfectant efficacy of 3 strategies for high-volume directed mist application of accelerated hydrogen peroxide and peroxymonosulfate disinfectants; 4.25% accelerated hydrogen peroxide (Accel(®) ; AHP) at a 1:16 dilution and single and double applications of 2% peroxymonosulfate solution (Virkon-S(®) ; VIR-1 and VIR-2) for decontamination of a large animal hospital environment. Experiment. After cleaning and disinfection of the hospital environment, transparencies experimentally contaminated with known concentrations of Staphylococcus aureus, Salmonella enterica and Pseudomonas aeruginosa were placed on vertical surfaces. Disinfectant solution was applied by directed mist application and, after 30 min of contact time, transparencies were collected and individually placed into tubes containing 10 ml Dey-Engley broth. The process was repeated for each disinfectant. Tenfold dilutions of each sample were plated onto tryptic soy blood agar with 5% sheep blood. Bacterial counts from transparencies exposed to disinfectants were compared with counts from control transparencies (unexposed to disinfectants) to evaluate reduction in colony forming units. The least squares mean reduction (log10 ) in colony forming units (CFUs) for S. aureus and P. aeruginosa was 1.5-2.5 logs and approximately 0.8-1.0 logs for S. enterica. Reductions were generally largest for VIR-2 and smallest for AHP, although these differences were not all statistically significant and the magnitude of differences may not be clinically relevant. For the organisms evaluated, all 3 disinfectants applied as a directed mist were effective at reducing CFUs in a veterinary hospital environment. Effective

  15. Accuracy and stability of impression materials subjected to chemical disinfection - a literature review.

    PubMed

    Kotsiomiti, E; Tzialla, A; Hatjivasiliou, K

    2008-04-01

    Disinfection of impressions by immersion or spraying with disinfecting solutions is considered nowadays mandatory for effective infection control. The purpose of this review was to examine existing evidence on the effects that chemical disinfection may have on critical qualities of impressions, namely dimensional accuracy and stability over time. A PubMed search was conducted to include original laboratory research articles written in English, published between 1980 and 2005 in peer-reviewed journals and investigating the effect of chemical disinfection, by immersion or spraying, on the dimensional changes that the impression materials experience after setting. Studies were also sought manually, by tracing the references cited in the retrieved articles. The reports on dimensional changes of disinfected impression materials, although rather numerous, are difficult to compare and analyze because of variations of the experimental design. The investigations broadly agree that the disinfection process does not generally affect the dimensional integrity of the impressions, in spite of the statistically significant differences occasionally found. However, the immersion in the disinfecting solution encourages water absorption phenomena in the case of the so-called hydrophilic impression materials, especially after the long-term immersion. Chemical interactions between impressions and disinfectants may occur, but they do not appear to influence the dimensional behaviour of the former. The overall effect of the disinfection is influenced not only by the changes experienced by the impression per se, but also by the alterations of the acrylic tray containing the impression and of the gypsum product poured in it.

  16. Tetranitromethane as a surface antiviral disinfectant.

    PubMed

    Singh, J S; Sonnenfeld, G; Doyle, R J

    1994-12-01

    Tetranitromethane, a protein nitrating agent, was tested for its ability to disinfect surfaces from viruses. Different surfaces on commercially available pocket calculators were pretreated with either the Indiana strain of vesicular stomatitis virus or the Herts' strain of Newcastle disease virus. The calculators surfaces were then sprayed with either tetranitromethane or control solutions. The calculators were incubated for 30 min at ambient temperature, and then the surfaces were wiped with sterile swabs. The swabs were placed into test tubes containing phosphate-buffered saline. Samples of the phosphate-buffered saline were then titered on appropriate cell lines by plaque assay. The results indicated that the amount of vesicular stomatitis virus and Newcastle disease virus recovered from the tetranitromethane-treated surfaces was dramatically decreased compared to the amount of virus recovered from control-treated surfaces. These data suggest that tetranitromethane may be useful to disinfect surfaces from both enveloped and non-enveloped RNA viruses.

  17. Silver as a disinfectant.

    PubMed

    Silvestry-Rodriguez, Nadia; Sicairos-Ruelas, Enue E; Gerba, Charles P; Bright, Kelly R

    2007-01-01

    Silver has been used as an antimicrobial for thousands of years. Over the past several decades, it has been introduced into numerous new venues such as in the treatment of water, in dietary supplements, in medical applications, and to produce antimicrobial coatings and products. Silver is often used as an alternative disinfectant in applications in which the use of traditional disinfectants such as chlorine may result in the formation of toxic by-products or cause corrosion of surfaces. Silver has also been demonstrated to produce a synergistic effect in combination with several other disinfectants. Many mechanisms of the antibacterial effect of silver have been described, but its antiviral and antiprotozoal mechanisms are not well understood. Both microbial tolerance and resistance to silver have been reported; however, the effect of silver has been observed against a wide variety of microorganisms over a period of years. Further research is needed to determine the antimicrobial efficacy of silver in these new applications and the effects of its long-term usage.

  18. Methodology for HIV disinfectant testing.

    PubMed

    van Bueren, J

    1995-06-01

    Due to the variation in protocols from studies by different workers for the inactivation of HIV by chemical disinfectants, only limited comparisons of the results can be made. These variations include those which apply to disinfectant testing in general, such as the level of organic load and the form of neutralization of the disinfectant, and those which apply particularly to HIV inactivation, such as the method used to detect infectious virus. Our suspension and carrier tests to assess the efficacy of chemical disinfectants against HIV are described and problems with the interpretation and applicability of the results are discussed.

  19. In-vitro analysis of the microbicidal activity of 6 contact lens care solutions

    PubMed Central

    2012-01-01

    Background Contact lens-related infections are often associated with inadequate contact lens hygiene, and therefore, contact lens care products should be able to sufficiently minimise the amount of pathogens that are responsible for these infections. In 2001, the EN ISO 14729 was introduced to ensure adequate disinfection efficacy of contact lens care solutions, but this norm has recently been criticised. Methods In this study, six frequently used contact lens care solutions were retested according to the Stand Alone Test of the EN ISO 14729 (2001). The Stand Alone Test is a quantitative suspension test. In addition, the products were tested in a modified setting adding an organic load. The load was a mixture of human blood serum, lysozyme, and mucine, which resembles tear fluid. Results The criteria of the Stand Alone Test recommended in EN ISO 14729 were only met by Aosept Plus. This 3% hydrogen-peroxide-based contact lens care solution attained a reduction factor of > 5 log units for bacteria and > 4 for fungi in all cases. Two further contact lens care solutions, Blue Vision and Optifree Replenish, met the criteria of a reduction factor of > 3 log units for bacteria and > 1 log unit for fungi, but only in the presence of artificial tear fluid. The three remaining products did not exhibit adequate disinfecting efficacy, at least against one of the tested microorganisms. Conclusions Through the observation that the artificial tear fluid used in this study influences the disinfecting efficacy of contact lens care solutions, especially that of multi-purpose solutions, in a different way than does albumin, mucine, or even the organic load suggested in EN ISO 14729, it becomes obvious that the test conditions in the EN ISO 14729 should be revised in order to create more realistic conditions, e.g., by using a more realistic artificial tear fluid. Furthermore, we suggest adapting the EN ISO 14729 to the European test hierarchy for chemical disinfectants and antiseptics

  20. Effect of well disinfection on arsenic in ground water

    USGS Publications Warehouse

    Gotkowitz, M.; Ellickson, K.; Clary, A.; Bowman, G.; Standridge, J.; Sonzogni, W.

    2008-01-01

    Domestic water wells are routinely subjected to in situ chemical disinfection treatments to control nuisance or pathogenic bacteria. Most treatments are chlorine based and presumably cause strongly oxidizing conditions in the wellbore. Water resource managers in Wisconsin were concerned that such treatments might facilitate release of arsenic from sulfide minerals disseminated within a confined sandstone aquifer. To test this hypothesis, a well was subjected to four disinfection treatments over 9 months time. The first treatment consisted of routine pumping of the well without chemical disinfection; three subsequent treatments included chlorine disinfection and pumping. Pretreatment arsenic concentrations in well water ranged from 7.4 to 18 ??g/L. Elevated arsenic concentrations up to 57 ??g/L in the chemical treatment solutions purged from the well are attributed to the disintegration or dissolution of biofilms or scale. Following each of the four treatments, arsenic concentrations decreased to less than 10 ??g/L during a period of pumping. Arsenic concentrations generally returned to pretreatment levels under stagnant, nonpumping conditions imposed following each treatment. Populations of iron-oxidizing, heterotrophic, and sulfate-reducing bacteria decreased following chemical treatments but were never fully eradicated from the well. Strongly oxidizing conditions were induced by the chlorine-based disinfections, but the treatments did not result in sustained increases in well water arsenic. Results suggest that disruption of biofilm and mineral deposits in the well and the water distribution system in tandem with chlorine disinfection can improve water quality in this setting. ?? 2008 The Author(s).

  1. Disinfection of dental diamond burs contaminated with hepatitis B virus.

    PubMed

    Leontiou, A P; Coogan, M M; Aspinall, S

    1999-09-01

    Hepatitis B infection (HBV) is a significant hazard in the dental environment because the virus may be transmitted through contaminated dental instruments. This study determined whether cold disinfectants can inactivate HBV DNA and HBV surface antigens on diamond burs contaminated with HBV and whether ultrasonication can increase the antiviral properties of these agents. Sterile dental diamond burs were contaminated with serum from a patient who tested positive for HBV surface antigen and hepatitis B viral DNA. The burs were air dried and placed in solutions containing either Cidex, Asepsys, TBS, Rotagerm, Virkon disinfectants, or a control phosphate buffered saline. Burs were divided into 2 groups and disinfected for 15 minutes. The first group was ultrasonicated; the second group was not ultrasonicated during disinfection. All the burs were transferred to phosphate buffered saline and ultrasonicated to remove any remaining viral particles. The ultrasonicate was tested for the presence of HBV surface antigen with a microparticle enzyme immunoassay and for hepatitis B viral DNA with a chemiluminescent molecular hybridization assay. TBS did not require ultrasonication to inactivate viral DNA and surface antigen. Rotagerm and Virkon inactivated surface antigen and viral DNA only with ultrasonication. Cidex and Asepsys inactivated viral DNA but not surface antigen with ultrasonication. The chlorine containing compound TBS was the most active disinfectant tested and did not require ultrasonication to destroy HBV. The remaining disinfectants should be used with ultrasonication to inactivate HBV.

  2. Effects of Disinfectants on Larval Development of Ascaris suum Eggs

    PubMed Central

    Oh, Ki-Seok; Kim, Geon-Tae; Ahn, Kyu-Sung; Shin, Sung-Shik

    2016-01-01

    The objective of this study was to evaluate the effects of several different commercial disinfectants on the embryogenic development of Ascaris suum eggs. A 1-ml aliquot of each disinfectant was mixed with approximately 40,000 decorticated or intact A. suum eggs in sterile tubes. After each treatment time (at 0.5, 1, 5, 10, 30, and 60 min), disinfectants were washed away, and egg suspensions were incubated at 25˚C in distilled water for development of larvae inside. At 3 weeks of incubation after exposure, ethanol, methanol, and chlorohexidin treatments did not affect the larval development of A. suum eggs, regardless of their concentration and treatment time. Among disinfectants tested in this study, 3% cresol, 0.2% sodium hypochlorite and 0.02% sodium hypochlorite delayed but not inactivated the embryonation of decorticated eggs at 3 weeks of incubation, because at 6 weeks of incubation, undeveloped eggs completed embryonation regardless of exposure time, except for 10% povidone iodine. When the albumin layer of A. suum eggs remained intact, however, even the 10% povidone iodine solution took at least 5 min to reasonably inactivate most eggs, but never completely kill them with even 60 min of exposure. This study demonstrated that the treatment of A. suum eggs with many commercially available disinfectants does not affect the embryonation. Although some disinfectants may delay or stop the embryonation of A. suum eggs, they can hardly kill them completely. PMID:26951988

  3. Effects of Disinfectants on Larval Development of Ascaris suum Eggs.

    PubMed

    Oh, Ki-Seok; Kim, Geon-Tae; Ahn, Kyu-Sung; Shin, Sung-Shik

    2016-02-01

    The objective of this study was to evaluate the effects of several different commercial disinfectants on the embryogenic development of Ascaris suum eggs. A 1-ml aliquot of each disinfectant was mixed with approximately 40,000 decorticated or intact A. suum eggs in sterile tubes. After each treatment time (at 0.5, 1, 5, 10, 30, and 60 min), disinfectants were washed away, and egg suspensions were incubated at 25˚C in distilled water for development of larvae inside. At 3 weeks of incubation after exposure, ethanol, methanol, and chlorohexidin treatments did not affect the larval development of A. suum eggs, regardless of their concentration and treatment time. Among disinfectants tested in this study, 3% cresol, 0.2% sodium hypochlorite and 0.02% sodium hypochlorite delayed but not inactivated the embryonation of decorticated eggs at 3 weeks of incubation, because at 6 weeks of incubation, undeveloped eggs completed embryonation regardless of exposure time, except for 10% povidone iodine. When the albumin layer of A. suum eggs remained intact, however, even the 10% povidone iodine solution took at least 5 min to reasonably inactivate most eggs, but never completely kill them with even 60 min of exposure. This study demonstrated that the treatment of A. suum eggs with many commercially available disinfectants does not affect the embryonation. Although some disinfectants may delay or stop the embryonation of A. suum eggs, they can hardly kill them completely.

  4. Surface-Dried Viruses Can Resist Glucoprotamin-Based Disinfection.

    PubMed

    Zeitler, Benjamin; Rapp, Ingrid

    2014-12-01

    Touching of contaminated objects and surfaces is a well-known method of virus transmission. Once they are attached to the hands, viruses can easily get adsorbed and initiate infection. Hence, disinfection of frequently touched surfaces is of major importance to prevent virus spreading. Here we studied the antiviral activity of a glucoprotamin-containing disinfectant against influenza A virus and the model virus vaccinia virus (VACV) dried on inanimate surfaces. The efficacy of the surface disinfectant on stainless steel, polyvinyl chloride, and glass coupons was investigated in a quantitative carrier test. Vacuum-dried viruses were exposed to 0.25%, 0.5%, and 1% disinfectant for 5 min, 15 min, and 30 min without agitation, and residual infectivity was determined by endpoint titration. Although glucoprotamin was highly active against both viruses in suspension, limited antiviral activity against the surface-dried viruses was detected. Even after 30 min of exposure to 1% disinfectant, VACV was not completely inactivated. Furthermore, influenza A virus inactivation was strongly affected by the surface composition during the 5-min and 15-min treatments with 0.25% and 0.5% disinfectant. The results presented in this study highlight the relevance of practical tests to assess the antiviral activity of surface disinfectants. High virucidal activity in solution is not necessarily indicative of high antiviral activity against surface-dried viruses. In addition, we want to emphasize that the mere exposure of surfaces to disinfectants might not be sufficient for virus inactivation and mechanical action should be applied to bring attached viruses into contact with virucidal compounds. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  5. [Aerosol disinfection of bacterial spores].

    PubMed

    Theilen, U; Wilsberg, F J; Böhm, R; Strauch, D

    1987-06-01

    The present investigations are divided into two parts. First it is tested which commercial disinfectants are efficient in aerosol disinfection of bacterial spores. This part is carried out in an aerosol chamber with airborne spores (laboratory experiments). The best results are obtained with peracetic acid, hydrogen peroxide and formaldehyde are effective with some restrictions. With these disinfectants it is tested in the second part if the aerosol disinfecting-method is capable for disinfecting rooms with electronic equipment. This part is carried out in a vessel under open air conditions (field experiments). Bacterial spores dried on germ carriers of limewood, aluminium and rusty iron are exposed to disinfectant aerosols under those temperature and relative humidity conditions which are representative for the four seasons in Germany. In these investigations there are also included germ carriers with spores, that have been lyophilized without any protective substances respectively with Bentonite, Mixtura desiccans and Silicagel + Serum as protective substances. To check the corrosive effect of disinfectant aerosols electronic pocket calculators and pocket transistor receivers have been exposed to the aerosols. The best results are obtained with formaldehyde at temperatures above 10 degrees C and relative humidities within 65% to 95%. At temperatures and relative humidity conditions outside of this optimal range the effectiveness of formaldehyde tends to zero. Hydrogen peroxide is capable for disinfecting spores on germ carriers of limewood and aluminium at all temperature and relative humidity conditions; on germ carriers of rusty iron the effectiveness is reduced strongly. Same results could be obtained with peracetic acid respectively a mixture of peracetic acid and hydrogen peroxide. With these disinfectants a decontamination of rusty iron surfaces is impossible too except the germ concentration on the surface is below 10(4) CFU/cm2. As to the protective

  6. Microwave disinfection of maxillary and mandibular denture bases contaminated with Candida Albican.

    PubMed

    Bamigboye, S A; Dosumu, O O; Ajayi, D M

    2015-09-01

    Oral environment is not sterile, and dentures worn by the patients can be infected and therefore needs disinfection. Solution disinfectants such as sodium hypochlorite and glutaraldehyde can be used but they have side effects. Microwave disinfection method is more recent, however, there are conflicting reports at the moment on the appropriate power and time regimen for disinfection of denture. To determine the power and time regimen at which the disinfection of dentures can be achieved using microwave. Forty-five acrylic denture bases were fabricated for each of the jaws and infected with solution of a stock Candida albicans and 30 infected bases were employed as control. These were placed in normal saline and then subjected to different microwave power and time regimen. Aliquots from these post-microwave solution were titrated against sabauraud agar which was subsequently incubated at 37 degrees C for 48 hours. The agar were examined for candida growth. The denture bases subjected to microwave disinfection at 350W showed Candida growth after microwave treatment irrespective of the time employed. Conversely, those microwaved at 650W and 690W for four and six minutes showed no microbial growth. The microwave regimen of 650W at 4 and 6 minutes completely disinfected the denture bases. Disinfection at higher microwave energy should be done with caution as distortion of the denture may occur.

  7. SCOPING EVALUATION TO EXPLORE - ROCK FALL ACCIDENT CONDITION ANALYSIS ON MULTI-PURPOSE CANISTER WASTE PACKAGES CORRELATED FROM INTERLOCKING BASKET WASTE PACKAGE DESIGN ANALYSIS (SCPB: N/A)

    SciTech Connect

    Z, Ceylan

    1995-12-08

    The objective of this analysis is to correlate the results of a rock fall analysis performed for the 12 Pressurized Water Reactor (PWR) Fuel Assembly Interlocking Basket waste package (WP) in order to determine the size of rock that can strike the Multi-Purpose Canister (MPC) waste packages without breaching the containment barriers. The purpose of this analysis is to document the models and methods used in the calculations.

  8. DISINFECTION BYPRODUCTS: THE NEXT GENERATION

    EPA Science Inventory

    Disinfection of drinking water is rightly hailed as a major public health triumph of the 20th Century. Before widespread disinfection of drinking water in the U.S. and Europe, millions of people died from infectious waterborne diseases, such as typhoid and cholera. The microbia...

  9. DISINFECTION BYPRODUCTS: THE NEXT GENERATION

    EPA Science Inventory

    Disinfection of drinking water is rightly hailed as a major public health triumph of the 20th Century. Before widespread disinfection of drinking water in the U.S. and Europe, millions of people died from infectious waterborne diseases, such as typhoid and cholera. The microbia...

  10. New Disinfection Agents for Water.

    DTIC Science & Technology

    1985-03-01

    with HTH being the better disinfectant. In similar experiments involving Entamoeba invadens and Giardia Lamblia Compound I was more effective than...different and dependent upon the nature of the organism. Keywords: Water disinfections; N-Chloramines; HTH; Bacteria; Viruses; Protozoa; Giardia lamblia ; Stability in water; 3-Chloro-4,4-dimethy1-2-oxazolidinone; Calcium hypochlorite.

  11. Sanitizers and Disinfectants Guide. Revised

    ERIC Educational Resources Information Center

    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…

  12. Multi-destination and multi-purpose trip effects in the analysis of the demand for trips to a remote recreational site.

    PubMed

    Martínez-Espiñeira, Roberto; Amoako-Tuffour, Joe

    2009-06-01

    One of the basic assumptions of the travel cost method for recreational demand analysis is that the travel cost is always incurred for a single purpose recreational trip. Several studies have skirted around the issue with simplifying assumptions and dropping observations considered as nonconventional holiday-makers or as nontraditional visitors from the sample. The effect of such simplifications on the benefit estimates remains conjectural. Given the remoteness of notable recreational parks, multi-destination or multi-purpose trips are not uncommon. This article examines the consequences of allocating travel costs to a recreational site when some trips were taken for purposes other than recreation and/or included visits to other recreational sites. Using a multi-purpose weighting approach on data from Gros Morne National Park, Canada, we conclude that a proper correction for multi-destination or multi-purpose trip is more of what is needed to avoid potential biases in the estimated effects of the price (travel-cost) variable and of the income variable in the trip generation equation.

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

    EPA Pesticide Factsheets

    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

  14. Disinfection of pumice.

    PubMed

    Setz, J; Heeg, P

    1996-10-01

    Pumice is a potential source of infection for the dental technician and of cross-contamination between different dentures and patients. In this study, the number of microorganisms in two different combinations of pumice and disinfectant was compared with a conventional mixture of pumice and water. The results revealed that under practical conditions the mix of Steribim (pumice containing benzoic acid added by the manufacturer) with water reduced the number of bacteria by 99% compared with a mix of a conventional pumice and water. The addition of an antiseptic product that contained octenidine as active agent to conventional pumice reduced the number of microorganisms by 99.999%.

  15. Effectiveness of disinfection therapies and promotion of osteoblast growth on osseotite and nanotite implant surfaces.

    PubMed

    Lubin, Judith; Hernandez, Maria A; Drukteinis, Saulius E; Parker, William B; Murray, Peter E

    2014-08-01

    To evaluate the effectiveness of 4 procedures to disinfect implant surfaces intentionally inoculated with bacteria and afterward to evaluate osteoblast viability to the disinfected implant surfaces. Eighty-eight commercially pure Osseotite and Nanotite titanium implant discs were inoculated with Porphyromonas gingivalis. The implant surfaces were disinfected with EDTA, tetracycline, citric acid, or neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. The implant discs were then placed in cultures of osteoblast cells. Osseotite implant discs were easier to disinfect compared with the Nanotite implant discs. Citric acid and tetracycline were the most effective solutions for the disinfection of P. gingivalis from the Osseotite implant discs. The Nanotite implant discs were the most difficult to disinfect, likely because of their chemical and physical properties. Citric acid and tetracycline were most effective for disinfecting the Osseotite implant discs, and further clinical research is needed to verify these effects in vivo. The Nd:YAG laser was the weakest disinfection method, and it is not recommended for disinfecting implant surfaces until its effectiveness is improved.

  16. Improved contact lens disinfection by exposure to violet radiation.

    PubMed

    Hoenes, Katharina; Stangl, Felix; Gross, Andrej; Hessling, Martin

    2016-01-01

    Conventional procedures for contact lens disinfection, based on solutions with aggressive chemical ingredients, not only affect microorganisms but operate likewise damaging towards the epithelial eye surface. The aim of this study was to evaluate the applicability of an alternative or complementary disinfection procedure for contact lenses based on irradiation within the visible wavelength range. Suspensions of S. auricularis, B. subtilis and E. coli were exposed to 405 nm irradiation, for determining the disinfection efficacy. Surviving rates were analyzed by membrane filtration as well as a semi-quantitative analysis using DipSlides. A significant antibacterial effect of the 405 nm irradiation is verifiable for all probed bacteria. Using S. auricularis, there has been no colony forming after an irradiation exposure of 2 hours. The hitherto existing results give reason for the assumption that violet LEDs integrated in contact lens cases will provide a subsidiary disinfection activity and maybe even offer the reduction of chemical ingredients in lens cleaning solutions to become gentler to the eye. In addition the danger of a rerise of the germ concentration after the completion of the disinfection procedure will be reduced.

  17. Occurrence and exposures to disinfectants and disinfection by-products

    SciTech Connect

    Cumming, R.B.; Jolley, R.L.

    1992-01-01

    Disinfection by-products are associated with all chemical disinfectants. The concentration and toxic nature of the disinfection byproducts (DBPs) is a direct function of the chemical nature of the disinfectant itself and/or of the chemical reactions of the disinfectant with reaction substrates in the water, especially organic constituents. A principal advantage of biological and physical water treatment processes, such as filtration, is the lack of chemical reactions producing disinfectant-related DBPs. The use of the highest quality source water available is important for minimization of DBP formation. In lieu of such high quality water, improvement of water quality by removal of DBP precursors through filtration or other means before application of chemical disinfectants is important. Most, if not all, water treatment experts are aware of these simplistic axioms. In view of the increasing knowledge being developed concerning DBPs including the identification of new'' DBPs, prudence dictates minimization of DBP formation. Wholesome drinking water is perhaps the biggest economic bargain available to consumers. The cost-effectiveness of water quality improvement should be evaluated with that in mind.

  18. Occurrence and exposures to disinfectants and disinfection by-products

    SciTech Connect

    Cumming, R.B.; Jolley, R.L.

    1992-12-31

    Disinfection by-products are associated with all chemical disinfectants. The concentration and toxic nature of the disinfection byproducts (DBPs) is a direct function of the chemical nature of the disinfectant itself and/or of the chemical reactions of the disinfectant with reaction substrates in the water, especially organic constituents. A principal advantage of biological and physical water treatment processes, such as filtration, is the lack of chemical reactions producing disinfectant-related DBPs. The use of the highest quality source water available is important for minimization of DBP formation. In lieu of such high quality water, improvement of water quality by removal of DBP precursors through filtration or other means before application of chemical disinfectants is important. Most, if not all, water treatment experts are aware of these simplistic axioms. In view of the increasing knowledge being developed concerning DBPs including the identification of ``new`` DBPs, prudence dictates minimization of DBP formation. Wholesome drinking water is perhaps the biggest economic bargain available to consumers. The cost-effectiveness of water quality improvement should be evaluated with that in mind.

  19. Effect of disinfectants on pseudomonads colonized on the interior surface of PVC pipes.

    PubMed Central

    Anderson, R L; Holland, B W; Carr, J K; Bond, W W; Favero, M S

    1990-01-01

    We investigated the effect of disinfectants on microbial contamination present on the interior surface of polyvinyl chloride (PVC) pipes filled with 600 ml of water contaminated with Pseudomonas pickettii and P. aeruginosa. After eight weeks, water was removed, and the test pipes exposed to various types of aqueous disinfectants. Disinfectant samples were removed, neutralized, and examined for recovery of microorganisms by membrane filtration. After seven-days exposure, disinfectant solutions were removed and pipes filled with sterile distilled water. Water was examined by membrane filtration at seven-day intervals to determine whether the organisms had survived in the pipes. Colonization of PVC surfaces were examined during each study phase by scanning electron-microscopy (SEM). P. aeruginosa was isolated directly from iodophor disinfectant, phenolic germicide, and iodophor antiseptic solutions. After addition of sterile water, P. aeruginosa was recovered from PVC pipes previously exposed to chlorine, phenolic, quaternary-ammonium, and iodophor disinfectants; P. pickettii was recovered from water in pipes treated with iodophor disinfectant, chlorine, and ethanol. The existence of glycocalyx-like cellular masses on the interior wall of PVC pipes most likely protected embedded organisms from the microbicidal action of some of the disinfectants tested and served as the reservoir for continuous contamination. Images FIGURE 1 PMID:2293797

  20. Effects of disinfectants in renal dialysis patients.

    PubMed Central

    Klein, E

    1986-01-01

    Patients receiving hemodialysis therapy risk exposure to both disinfectants and sterilants. Dialysis equipment is disinfected periodically with strong solutions of hypochlorite or formaldehyde. More recently, reuse of dialyzers has introduced the use of additional sterilants, such as hydrogen peroxide and peracetic acid. The use of these sterilants is recognized by the center staffs and the home patient as a potential risk, and residue tests are carried out for the presence of these sterilants at the ppm level. Gross hemolysis resulting from accidental hypochlorite infusion has led to cardiac arrest, probably as a result of hyperkalemia. Formaldehyde is commonly used in 4% solutions to sterilize the fluid paths of dialysis controllers and to sterilize dialyzers before reuse. It can react with red cell antigenic surfaces leading to the formation of anti-N antibodies. Such reactions probably do not occur with hypochlorite or chloramines. The major exposure risk is the low concentration of disinfectant found in municipal water used to prepare 450 L dialysate weekly. With thrice-weekly treatment schedules, the quality requirements for water used to make this solution must be met rigorously. Standards for water used in the preparation of dialysate have recently been proposed but not all patients are treated with dialysate meeting such standards. The introduction of sterilants via tap water is insidious and has led to more pervasive consequences. Both chlorine and chloramines, at concentrations found in potable water, are strong oxidants that cause extensive protein denaturation and hemolysis. Oxidation of the Fe2+ in hemoglobin to Fe3+ forms methemoglobin, which is incapable of carrying either O2 or CO2.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3816735

  1. Evaluation of the antimicrobial activity and dimensional alterations of alginate impression disinfectants.

    PubMed

    Semensato, Ana Paula Nocentini; Crosariol, Sonia Khouri; Marchini, Leonardo

    2009-09-01

    This paper offers a quantitative evaluation of the antimicrobial efficacy of eight different disinfection procedures for irreversible hydrocolloid impressions and the dimensional changes induced by them. Samples were collected immediately after impressions, after the disinfection procedures and over casts and analyzed for bacterial growth. Control, enzyme solutions, acetic acid and ultraviolet irradiation samples showed bacterial growth. Chlorhexidine and 1% sodium hypochlorite presented adequate antimicrobial activity, while 2% sodium hypochlorite solution showed the best results. Dimensional changes were similar to those of the controls in all the tested agents. The results indicated 2% hypochlorite was the most appropriate disinfectant tested.

  2. [Use of corrosion inhibitors during the sterilization and disinfection of medical instruments].

    PubMed

    Talalina, A S; Kochanova, L G; Anan'eva, A I; Romanova, A A

    1984-01-01

    The search of corrosion inhibitors reducing the corrosive action of the sterilizing and disinfecting media has been performed in order to protect instruments made of metals against corrosion during these processes. The program of the investigations includes potentiodynamic and potentiostatic measurements and full-scale tests. The infection of the sodium benzoate or potassium gluconate into the disinfecting chloramine solution and sterilizing hydrogene peroxide solution has been shown to improve the resistance to the corrosion for medical instruments made of carbon steel.

  3. Observations on a new disinfectant

    PubMed Central

    Gordon, A. M.

    1969-01-01

    A disinfectant formula (Resiguard) containing picloxydine digluconate, benzalkonium chloride, and a detergent was examined for antibacterial activity. Studies in vitro with simulated organic contamination were followed by realistic in-use tests employing items of anaesthetic and urological equipment heavily infected with Pseudomonas aeruginosa and contaminated with blood. These showed that a dilution of 1/80 was reliably bactericidal to this resistant organism. It is concluded that Resiguard is a valuable disinfectant which may reliably be employed in the cleaning and disinfection of items of delicate, non-autoclavable, hospital equipment. PMID:4978998

  4. Dental unit waterlines disinfection using hypochlorous acid-based disinfectant

    PubMed Central

    Shajahan, Irfana Fathima; Kandaswamy, D; Srikanth, Padma; Narayana, L Lakshmi; Selvarajan, R

    2016-01-01

    Objective: The purpose of the study was to investigate the efficacy of a new disinfectant to disinfect the dental unit waterlines. Materials and Methods: New dental unit waterlines were installed in 13 dental chairs, and biofilm was allowed to grow for 10 days. Disinfection treatment procedure was carried out in the 12 units, and one unit was left untreated. The dental unit waterlines were removed and analyzed using the scanning electron microscope (SEM) (TESCAN VEGA3 SBU). Result: On examination, SEM images showed that there was no slime layer or bacterial cells seen in any of the 12 cut sections obtained from the treated dental waterlines which mean that there was no evident of biofilm formation. Untreated dental unit waterlines showed a microbial colonization with continuous filamentous organic matrix. There was significant biofilm formation in the control tube relative to the samples. Conclusion: The tested disinfectant was found to be effective in the removal of biofilm from the dental unit waterlines. PMID:27563184

  5. THERMAL EVALUATION OF THE USE OF BWR MOX SNF IN THE MULTI-PURPOSE CANISTER (MPC) WITH ACD DISPOSAL CONTAINER (SCPB: N/A)

    SciTech Connect

    T.L. Lotz

    1995-11-13

    This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development Department (WPDD) as specified in the Waste Package Implementation Plan (pp. 4-8,4-11,4-24,5-1, and 5-13; Ref. 5.10) and Waste Package Plan (pp. 3-15,3-17, and 3-24; Ref. 5.9). The design data request addressed herein is: (1) Characterize the conceptual 40 BWR Multi-Purpose Canister (MPC) Waste Package (WP) design to show that the design is feasible for use in the MGDS environment when loaded with BWR MOX SNF. (2) Characterize the conceptual 24 BWR Multi-Purpose Canister (MPC) Waste Package (WP) design to show that the design is feasible for use in the MGDS environment when loaded with BWR MOX SNF. The purpose of this analysis is to respond a concern that the long-term disposal thermal issues for the Multi-Purpose Canister (MPC) Subsystem Design, if used with SNF designed for a MOX fuel cycle, do not preclude MPC compatibility with the MGDS. The objective of this analysis is to provide thermal parameter information for the conceptual MPC design with disposal container which is loaded with BWR MOX SNF under nominal MGDS repository conditions. The results are intended to show that the design has a reasonable chance to meet the MGDS design requirements for normal MGDS operation, to provide the required guidance to determining the major design issues for future design efforts, and to show that the BWR MOX SNF loaded MPC performance is similar to an MPC loaded with commercial BWR SNF. Future design efforts will focus on specific MPC vendor designs and BWR MOX SNF designs when they become available.

  6. [Disinfection of devices for nebulization: stakes, difficulties, and improvement proposals].

    PubMed

    Reychler, G; Dupont, C; Dubus, J C

    2007-12-01

    Nebulization may transport with the drug some small particles containing microbes. These microbes may be present in all parts of the nebulizer, including the drug solution itself. Depending on the studies, contamination of the nebulizers may reach up to 55% of the devices in patients with cystic fibrosis. That's why using one nebulizer for one patient, using drug sterile ampoules, and having a good hygiene during and after the nebulization are so important. The national disinfection recommendations, usually depending on the type of the nebulizer, are variable from one to another country and are not very well validated. Moreover, the repetitive use of these disinfection techniques on the performances of the nebulizer are neither studied. In daily life, the patients respect these disinfection recommendations in 3 to 98% of the cases. We propose a standardized methodology for evaluating the microbial and functional effects of all disinfectants on the nebulizers. A simple, quick, efficacious, cheap, and without effect on nebulizer performances disinfectant is still waiting.

  7. Evaluation of in vitro efficacy of the disinfectant Virkon.

    PubMed

    Gasparini, R; Pozzi, T; Magnelli, R; Fatighenti, D; Giotti, E; Poliseno, G; Pratelli, M; Severini, R; Bonanni, P; De Feo, L

    1995-04-01

    A study was conducted on a new acid peroxygen system based disinfectant (Virkon), in order to assess its in vitro efficacy. The chemical was tested on different bacteria (Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli), spores (Bacillus subtilis) and on the Hepatitis B surface antigen (HBsAg), and compared in its activity with phenol and glutaraldehyde (calculation of the 'phenol coefficient' and the 'glutaraldehyde coefficient'). The constancy of speed of disinfection, the coefficient of concentration, the minimal inhibitory concentration (MIC) were also determined, and the destruction of the HBsAg antigenic activity was studied using an ELISA kit. The sporicidal efficacy of Virkon was assessed by cultivating spores in agar nutrient after contact with different dilutions of the disinfectant. The results of the tests showed that Virkon has a high concentration coefficient (mean value of k: 0.374/min) and a wide range of action. The low MIC demonstrates how little concentrations of Virkon can inactivate all studied bacteria. The disinfectant was also able to destroy the hepatitis B surface antigen, and it demonstrated good activity against spores, especially if used in physiologic solution. These characteristics, coupled with the absence of initiation or toxic effects on animals showed by other studies, make wide fields of application for the new disinfectant foreseeable.

  8. Spin Forming of an Aluminum 2219-T6 Aft Bulkhead for the Orion Multi-Purpose Crew Vehicle: Phase II Supplemental Report

    NASA Technical Reports Server (NTRS)

    Piascik, Robert S.; Squire, Michael D.; Domack, Marcia S.; Hoffman, Eric K.

    2015-01-01

    The principal focus of this project was to assist the Orion Multi-Purpose Crew Vehicle (MPCV) Program in developing a spin forming fabrication process for manufacture of the aft bulkhead of the pressure vessel. The spin forming process will enable a single piece aluminum (Al) 2219 aft bulkhead which will eliminate the current multiple piece welded construction, simplify fabrication, and lead to an enhanced design that will reduce vehicle weight by eliminating welds. Phase I of this assessment explored spin forming the single-piece forward pressure vessel bulkhead from aluminum-lithium 2195.

  9. The Role of Combination Techniques in Maximizing the Utility of Precipitation Estimates from Several Multi-Purpose Remote-Sensing Systems

    NASA Technical Reports Server (NTRS)

    Huffman, George J.; Adler, Robert F.; Bolvin, David T.; Curtis, Scott; Einaudi, Franco (Technical Monitor)

    2001-01-01

    Multi-purpose remote-sensing products from various satellites have proved crucial in developing global estimates of precipitation. Examples of these products include low-earth-orbit and geosynchronous-orbit infrared (leo- and geo-IR), Outgoing Longwave Radiation (OLR), Television Infrared Operational Satellite (TIROS) Operational Vertical Sounder (TOVS) data, and passive microwave data such as that from the Special Sensor Microwave/ Imager (SSM/I). Each of these datasets has served as the basis for at least one useful quasi-global precipitation estimation algorithm; however, the quality of estimates varies tremendously among the algorithms for the different climatic regions around the globe.

  10. Susceptibility of high-risk human papillomavirus type 16 to clinical disinfectants.

    PubMed

    Meyers, Jordan; Ryndock, Eric; Conway, Michael J; Meyers, Craig; Robison, Richard

    2014-06-01

    Little to nothing is known about human papillomavirus (HPV) susceptibility to disinfection. HPV is estimated to be among the most common sexually transmitted diseases in humans. HPV is also the causative agent of cervical cancers and other anogenital cancers and is responsible for a significant portion of oropharyngeal cancers. While sexual transmission is well documented, vertical and non-sexual transmission may also be important. Using recombinant HPV16 particles (quasivirions) and authentic HPV16 grown in three-dimensional organotypic human epithelial culture, we tested the susceptibility of high-risk HPV to clinical disinfectants. Infectious viral particles were incubated with 11 common clinical disinfectants, appropriate neutralizers were added to inactivate the disinfectant and solutions were filter centrifuged. Changes in the infectivity titres of the disinfectant-treated virus were measured compared with untreated virus. HPV16 is a highly resistant virus; more so than other non-enveloped viruses previously tested. The HPV16 quasivirions showed similar resistance to native virions, except for being susceptible to isopropanol, the triple phenolic and the lower concentration peracetic acid-silver (PAA-silver)-based disinfectant. Authentic virus and quasivirus were resistant to glutaraldehyde and ortho-phthalaldehyde and susceptible to hypochlorite and the higher concentration PAA-silver-based disinfectant. We present the first disinfectant susceptibility data on HPV16 native virions, which show that commonly used clinical disinfectants, including those used as sterilants in medical and dental healthcare facilities, have no effect on HPV16 infectivity. Policy changes concerning disinfectant use are needed. The unusually high resistance of HPV16 to disinfection supports other data suggesting the possibility of fomite or non-sexual transmission of HPV16. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial

  11. Susceptibility of high-risk human papillomavirus type 16 to clinical disinfectants

    PubMed Central

    Meyers, Jordan; Ryndock, Eric; Conway, Michael J.; Meyers, Craig; Robison, Richard

    2014-01-01

    Objectives Little to nothing is known about human papillomavirus (HPV) susceptibility to disinfection. HPV is estimated to be among the most common sexually transmitted diseases in humans. HPV is also the causative agent of cervical cancers and other anogenital cancers and is responsible for a significant portion of oropharyngeal cancers. While sexual transmission is well documented, vertical and non-sexual transmission may also be important. Methods Using recombinant HPV16 particles (quasivirions) and authentic HPV16 grown in three-dimensional organotypic human epithelial culture, we tested the susceptibility of high-risk HPV to clinical disinfectants. Infectious viral particles were incubated with 11 common clinical disinfectants, appropriate neutralizers were added to inactivate the disinfectant and solutions were filter centrifuged. Changes in the infectivity titres of the disinfectant-treated virus were measured compared with untreated virus. Results HPV16 is a highly resistant virus; more so than other non-enveloped viruses previously tested. The HPV16 quasivirions showed similar resistance to native virions, except for being susceptible to isopropanol, the triple phenolic and the lower concentration peracetic acid-silver (PAA-silver)-based disinfectant. Authentic virus and quasivirus were resistant to glutaraldehyde and ortho-phthalaldehyde and susceptible to hypochlorite and the higher concentration PAA-silver-based disinfectant. Conclusions We present the first disinfectant susceptibility data on HPV16 native virions, which show that commonly used clinical disinfectants, including those used as sterilants in medical and dental healthcare facilities, have no effect on HPV16 infectivity. Policy changes concerning disinfectant use are needed. The unusually high resistance of HPV16 to disinfection supports other data suggesting the possibility of fomite or non-sexual transmission of HPV16. PMID:24500190

  12. Estimating Retrospective Exposure of Household Humidifier Disinfectants

    PubMed Central

    Park, Dong-Uk; Friesen, Melissa C; Roh, Hyun-Suk; Choi, Ye-Yong; Ahn, Jong-Ju; Lim, Heung-Kyu; Kim, Sun-Kyung; Koh, Dong-Hee; Jung, Hye-Jung; Lee, Jong-Hyeon; Cheong, Hae-Kwan; Lim, Sin-Ye; Leem, Jong-Han; Kim, Yong-Hwa; Paek, Do-Myung

    2014-01-01

    We conducted a comprehensive humidifier disinfectant exposure characterization for 374 subjects with lung disease who presumed their disease was related to humidifier disinfectant use (patient group) and for 303 of their family members (family group) for an ongoing epidemiological study. We visited the homes of the registered patients to investigate disinfectant use characteristics. Probability of exposure to disinfectants was determined from the questionnaire and supporting evidence from photographs demonstrating the use of humidifier disinfectant, disinfectant purchase receipts, any residual disinfectant and the consistency of their statements. Exposure duration was estimated as cumulative disinfectant use hours from the questionnaire. Airborne disinfectant exposure intensity (μg/m3) was estimated based on the disinfectant volume (mL) and frequency added to the humidifier per day, disinfectant bulk level (μg/mL), the volume of the room (m3) with humidifier disinfectant, and the degree of ventilation. Overall, the distribution patterns of the intensity, duration and cumulative exposure to humidifier disinfectants for the patient group were higher than those of the family group, especially for pregnant women and patients ≤ 6 years old. Further study is underway to evaluate the association between the disinfectant exposure estimated here with clinically diagnosed lung disease. PMID:25557769

  13. [Microbiological assesssment of efficiency chemothermal disinfection of blood contaminated hospital textiles].

    PubMed

    Röhm-Rodowald, Ewa; Jakimiak, Bozenna; Podgórska, Marta; Chojecka, Agnieszka

    2010-01-01

    Thermal disinfection should be applied to laundering procedures of hospital textiles contaminated with blood. Currently, there is an increasing number of hospital textiles composed of cotton-polyester blends that cannot endure high temperatures of thermal disinfection. Besides, decreasing the temperature of chemothermal disinfection enhances the possibility of micro-organisms to survive the laundering procedure. The aim of this study was to prepare a new method for the microbiological evaluation of disinfecting laundering procedures for hospital textiles contaminated with blood. The bactericidal activity of chemical disinfectants for chemothermal disinfection was determined by simulating a laundering procedure for hospital textiles in the laboratory according to procedure of National Institute of Hygiene - DF/05/03. Bioindicators cotton carriers inoculated with Enterococcus faecium were used for determinating the antibacterial effects for hospital textiles contaminated with blood. High concentrations of bovine albumin and/or sheep erythrocytes were used as substrate for simulating human blood. The results showed that the bactericidal activity of chemical disinfectants for chemothermal disinfection hospital textiles in the event of massive organic contamination--heavily soiled with blood, shall be evaluated using carrier test in following conditions: test organism- Enterococcus faecium, interfering substances--6 g/l bovine albumin solution added to preparation.

  14. Evaluation of commonly-used farm disinfectants in wet and dry models of Salmonella farm contamination.

    PubMed

    McLaren, Ian; Wales, Andrew; Breslin, Mark; Davies, Robert

    2011-02-01

    Two experimental models of Salmonella contamination were used in an attempt to mimic the conditions of disinfectant use on farms. A wet model, for conditions such as boot dips, used disinfectant application to a slurry of poultry faeces inoculated with Salmonella Enteritidis or Salmonella Typhimurium. A dry model, for disinfectant application to surfaces and equipment with adherent or residual organic material, used Salmonella-inoculated poultry faeces that were air-dried onto wooden dowels, immersed in disinfectant solution then left in air at room temperature overnight. All samples were subjected to a disinfectant neutralization step and resuscitation in broth, followed by Salmonella culture on semi-solid then indicator media. Disinfectants were tested at 0.5x, 1x and 2x the concentrations specified for the general control of bacterial pathogens on livestock premises in the UK (Defra General Orders rates). Chlorocresol-based disinfectants provided consistently high rates of Salmonella killing in both wet and dry tests. Formaldehyde-containing disinfectants showed very high efficacy in the dry test but were less effective in the shorter wet test, whereas the efficacy of glutaraldehyde without formaldehyde was variable between products. Other chemical classes tested (quaternary ammonium compounds, amphoteric surfactants, iodine preparations, peroxygens and a substituted phenol blend) were only moderately effective. They often required concentrations above General Orders rates to eliminate the test salmonellas, and frequently elimination was not achieved even under maximal conditions of concentration and exposure.

  15. Evaluation of properties of irreversible hydrocolloid impression materials mixed with disinfectant liquids.

    PubMed

    Amalan, Arul; Ginjupalli, Kishore; Upadhya, Nagaraja

    2013-01-01

    Addition of disinfectant to irreversible hydrocolloid impression materials can eliminate the disinfection step to avoid dimensional changes associated with it. The aim of the present study was to evaluate the effect of various disinfectant mixing liquids on the properties of commercially available irreversible hydrocolloid impression materials. Four commercially available irreversible hydrocolloid impression materials (Zelgan, Vignette, Tropicalgin, and Algitex) were mixed with disinfectant liquid containing chlorhexidine (0.1 and 0.2%) and sodium hypochlorite (0.1 and 0.5%). After mixing with disinfectant liquids, materials were evaluated for pH changes during gelation, gelation time, flow, gel strength, permanent deformation and detail reproduction. Significant changes in gelation time were observed in irreversible hydrocolloid impression materials upon mixing with disinfectant liquids. In general, chlorhexidine increased the gelation time, whereas sodium hypochlorite reduced it. However, no significant changes in the flow were observed both with chlorhexidine and sodium hypochlorite. Gel strength was found to decrease when mixed with chlorhexidine, whereas an increase in gel strength was observed upon mixing with sodium hypochlorite. Permanent deformation of the most irreversible hydrocolloid impression materials was below the specification limit even after mixing with disinfectant liquids. Sodium hypochlorite significantly reduced the surface detail reproduction, whereas no change in detail reproduction was observed with chlorhexidine. Chlorhexidine solution can be used to mix irreversible hydrocolloid impression materials in regular dental practice as it did not significantly alter the properties. This may ensure effective disinfection of impressions.

  16. Evaluation of properties of irreversible hydrocolloid impression materials mixed with disinfectant liquids

    PubMed Central

    Amalan, Arul; Ginjupalli, Kishore; Upadhya, Nagaraja

    2013-01-01

    Background: Addition of disinfectant to irreversible hydrocolloid impression materials can eliminate the disinfection step to avoid dimensional changes associated with it. The aim of the present study was to evaluate the effect of various disinfectant mixing liquids on the properties of commercially available irreversible hydrocolloid impression materials. Materials and Methods: Four commercially available irreversible hydrocolloid impression materials (Zelgan, Vignette, Tropicalgin, and Algitex) were mixed with disinfectant liquid containing chlorhexidine (0.1 and 0.2%) and sodium hypochlorite (0.1 and 0.5%). After mixing with disinfectant liquids, materials were evaluated for pH changes during gelation, gelation time, flow, gel strength, permanent deformation and detail reproduction. Results: Significant changes in gelation time were observed in irreversible hydrocolloid impression materials upon mixing with disinfectant liquids. In general, chlorhexidine increased the gelation time, whereas sodium hypochlorite reduced it. However, no significant changes in the flow were observed both with chlorhexidine and sodium hypochlorite. Gel strength was found to decrease when mixed with chlorhexidine, whereas an increase in gel strength was observed upon mixing with sodium hypochlorite. Permanent deformation of the most irreversible hydrocolloid impression materials was below the specification limit even after mixing with disinfectant liquids. Sodium hypochlorite significantly reduced the surface detail reproduction, whereas no change in detail reproduction was observed with chlorhexidine. Conclusion: Chlorhexidine solution can be used to mix irreversible hydrocolloid impression materials in regular dental practice as it did not significantly alter the properties. This may ensure effective disinfection of impressions. PMID:23878566

  17. Toxicology of household cleaning products and disinfectants.

    PubMed

    Kore, A M; Kiesche-Nesselrodt, A

    1990-03-01

    Hundreds of different household cleaning products are available in homes, presenting potential hazards to pets. These products are complex mixtures of chemicals that vary widely in their toxic potential. Prevention of toxicoses in companion animals follows the same guidelines as those recommended for children: Keep cleaning products out of the reach of pets, do not leave open containers or solutions of cleaning products unattended where animals may get into them, make sure containers of cleaning products are tightly sealed and properly labeled, and dispose of any cleaning solutions promptly after use. If a companion animal has ingested or spilled a cleaning product or disinfectant on itself, it is very important to assess the potential hazard to the animal promptly. Many products contain warnings regarding the corrosive or irritation potential of the product and instructions on the label for preliminary action in the case of accidental oral, dermal, or ocular exposures in humans. These instructions can generally be followed initially until further information on the product can be obtained, although the recommendations on some product labels may be outdated. In general, the clinical management for toxicoses caused by cleaning products and disinfectants involves the prevention of further contact with the concentrated product through either dilution or bathing; emergency stabilization of the patient if clinical signs are present; instituting specific therapies, if available; and use of general supportive care.

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

    PubMed

    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.

  19. Effect of different disinfecting procedures on the hardness and color stability of two maxillofacial elastomers over time

    PubMed Central

    ELENI, Panagiota N.; KROKIDA, Magdalini K.; POLYZOIS, Gregory L.; GETTLEMAN, Lawrence

    2013-01-01

    Objective: Disinfection procedures often cause deterioration in a maxillofacial prosthesis. Color and hardness alterations could lead to a replacement of the prosthesis. Material and Methods: An experimental chlorinated polyethylene (CPE) and a commercial polydimethyl siloxane (PDMS) sample were treated with four different disinfection procedures for a period which simulates 1 year of clinical service. The applied disinfection procedures included microwave exposure and immersion in three solutions, sodium hypochlorite, neutral soap and a commercial disinfecting soap. Shore A hardness (ΔΗ) and color differences (ΔΕ) were determined before and after each procedure. All data were analyzed by Two Way Analysis of Variance (ANOVA) and Tukey's post hoc tests at a level of α=0.05. Results: The samples presented significant alterations in color and hardness after the different disinfection treatments. The color differences (ΔΕ) were at least eye detectable in all cases and clinically unacceptable in most of the cases, with values ranging from 1.51 to 4.15 and from 1.54 to 5.92 for the PDMS and CPE material, respectively. Hardness was decreased after all the disinfection procedures in the PDMS, while for the CPE, a decrement was observed after disinfection with sodium hypochlorite and neutral soap and an increment after microwave exposure and the disinfection with a commercial antimicrobial agent. The PDMS samples presented greater alterations in color and hardness after disinfection with sodium hypochlorite solution, while the microwave exposure caused negligible effects. The CPE samples were affected most after disinfection when treated with neutral soap, and more slightly when disinfected with sodium hypochlorite solution. Conclusions: The disinfection procedures caused alterations in color and hardness of the examined materials. The most suitable disinfection procedure for the PDMS material is microwave exposure, while disinfection with sodium hypochlorite

  20. On the cause of the tailing phenomenon during virus disinfection by chlorine dioxide.

    PubMed

    Sigstam, Thérèse; Rohatschek, Andreas; Zhong, Qingxia; Brennecke, Moritz; Kohn, Tamar

    2014-01-01

    This study investigates the mechanisms underlying the deviation from Chick-Watson kinetics, namely a tailing curve, during the disinfection of viruses by chlorine dioxide (ClO2). Tailing has been previously reported, but is typically attributed to the decay in disinfectant concentration. Herein, it is shown that tailing occurs even at constant ClO2 concentrations. Four working hypothesis to explain the cause of tailing were tested, specifically changes in the solution's disinfecting capacity, aggregation of viruses, resistant virus subpopulations, and changes in the virus properties during disinfection. In experiments using MS2 as a model virus, it was possible to rule out the solution's disinfecting capacity, virus aggregation and the resistant subpopulation as reasons for tailing. Instead, the cause for tailing is the deposition of an adduct onto the virus capsid over the course of the experiment, which protects the viruses. This adduct could easily be removed by washing, which restored the susceptibility of the viruses to ClO2. This finding highlights an important shortcoming of ClO2, namely its self-limiting effect on virus disinfection. It is important to take this effect into account in treatment applications to ensure that the water is sufficiently disinfected before human consumption.

  1. The influence of storing alginate impressions sprayed with disinfectant on dimensional accuracy and deformation of maxillary edentulous stone models.

    PubMed

    Hiraguchi, Hisako; Kaketani, Masahiro; Hirose, Hideharu; Yoneyama, Takayuki

    2010-05-01

    This study investigated the effects of storing impressions for 3 hours after spraying them with a disinfectant solution on dimensional change and deformation of maxillary edentulous stone models. Three brands of alginate impression materials, characterized by a small degree of contraction in 100% relative humidity, were used. The spray disinfectants used were 1% sodium hypochlorite solution and 2% glutaraldehyde solution. A stone model taken from an impression that had not been sprayed or stored was prepared as a control. The results indicated that the differences in dimensional change between the control and disinfected stone models were less than 24 mum, and that no deformation was observed in the stone models.

  2. Health effects of drinking water disinfectants and disinfection by-products

    SciTech Connect

    Condie, L.W.; Bercz, J.P.

    1986-01-01

    This paper summarizes toxicological studies conducted with drinking water disinfectants. Toxicological effects, which are associated with the disinfectants themselves as well as with the by-products formed when disinfectants react with organic material present in water, are considered. The health impact of chemical reactions occurring between residual disinfectants and nutrients in the gastrointestinal tract is also discussed. 40 references, 5 tables.

  3. 40 CFR 141.54 - Maximum residual disinfectant level goals for disinfectants.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Maximum residual disinfectant level goals for disinfectants. 141.54 Section 141.54 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Goals and Maximum Residual Disinfectant Level Goals § 141.54 Maximum residual disinfectant level goals...

  4. 40 CFR 141.54 - Maximum residual disinfectant level goals for disinfectants.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Maximum residual disinfectant level goals for disinfectants. 141.54 Section 141.54 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Goals and Maximum Residual Disinfectant Level Goals § 141.54 Maximum residual disinfectant level goals...

  5. 40 CFR 141.54 - Maximum residual disinfectant level goals for disinfectants.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Maximum residual disinfectant level goals for disinfectants. 141.54 Section 141.54 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Goals and Maximum Residual Disinfectant Level Goals § 141.54 Maximum residual disinfectant level goals...

  6. 40 CFR 141.54 - Maximum residual disinfectant level goals for disinfectants.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Maximum residual disinfectant level goals for disinfectants. 141.54 Section 141.54 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Goals and Maximum Residual Disinfectant Level Goals § 141.54 Maximum residual disinfectant level goals...

  7. Preliminary SEM Observations on the Surface of Elastomeric Impression Materials after Immersion or Ozone Disinfection

    PubMed Central

    Prombonas, Anthony; Yannikakis, Stavros; Karampotsos, Thanasis; Katsarou, Martha-Spyridoula; Drakoulis, Nikolaos

    2016-01-01

    Introduction Surface integrity of dental elastomeric impression materials that are subjected to disinfection is of major importance for the quality of the final prosthetic restorations. Aim The aim of this qualitative Scanning Electronic Microscopy (SEM) study was to reveal the effects of immersion or ozone disinfection on the surface of four dental elastomeric impression materials. Materials and Methods Four dental elastomeric impression material brands were used (two vinyl polysiloxane silicones, one polyether, and one vinyl polyether silicone). Total of 32 specimens were fabricated, eight from each impression material. Specimens were immersion (0.525% sodium hypochlorite solution or 0.3% benzalkonium chloride solution) or ozone disinfected or served as controls and examined with SEM. Results Surface degradation was observed on several speci-mens disinfected with 0.525% sodium hypochlorite solution. Similar wavy-wrinkling surface structures were observed in almost all specimens, when treated either with 0.3% benzalkonium chloride solution or ozone. Conclusion The SEM images obtained from this study revealed that both immersion disinfectants and ozone show similar impression material surface alterations. Ozone seems to be non-inferior as compared to immersion disinfectants, but superior as to environmental protection. PMID:28208993

  8. Preliminary SEM Observations on the Surface of Elastomeric Impression Materials after Immersion or Ozone Disinfection.

    PubMed

    Poulis, Nikolas; Prombonas, Anthony; Yannikakis, Stavros; Karampotsos, Thanasis; Katsarou, Martha-Spyridoula; Drakoulis, Nikolaos

    2016-12-01

    Surface integrity of dental elastomeric impression materials that are subjected to disinfection is of major importance for the quality of the final prosthetic restorations. The aim of this qualitative Scanning Electronic Microscopy (SEM) study was to reveal the effects of immersion or ozone disinfection on the surface of four dental elastomeric impression materials. Four dental elastomeric impression material brands were used (two vinyl polysiloxane silicones, one polyether, and one vinyl polyether silicone). Total of 32 specimens were fabricated, eight from each impression material. Specimens were immersion (0.525% sodium hypochlorite solution or 0.3% benzalkonium chloride solution) or ozone disinfected or served as controls and examined with SEM. Surface degradation was observed on several speci-mens disinfected with 0.525% sodium hypochlorite solution. Similar wavy-wrinkling surface structures were observed in almost all specimens, when treated either with 0.3% benzalkonium chloride solution or ozone. The SEM images obtained from this study revealed that both immersion disinfectants and ozone show similar impression material surface alterations. Ozone seems to be non-inferior as compared to immersion disinfectants, but superior as to environmental protection.

  9. Rapid microbial quantification of disinfected contact lens surfaces.

    PubMed

    Powers, Linda S; Snyder, Robert W; Wardell, Lois J

    2012-09-01

    The efficacy of disinfection of contact lenses is difficult to determine. We have monitored microbial contamination on surfaces and in fluids by intrinsic fluorescence of microbes and distinguished their metabolic states (viable cells, nonviable cells, and endospores). This approach is sensitive (10 cells), requires no added reagents or sample contact, and measurements can be made in near real time. The disinfection performance of AMO Easy Rub™ and Alcon No Rub™ contact lens solutions was compared with CVS-brand saline for contact lenses on contact lenses contaminated with Pseudomonas aeruginosa (ATCC 10145). Our aim is to show that intrinsic fluorescence measurements can yield real-time, critical information about the efficacy of contact lens decontamination products and protocols. Intrinsic fluorescence of Acuvue™ contact lenses (samples and controls) was measured before and after incubation with P. aeruginosa. Inoculated lenses were then cleaned and disinfected, according to directions for AMO Easy Rub™ and Alcon No Rub™, rubbed and rinsed with saline for contact lenses (the brand made a difference in the experiment), followed by measurement of the effectiveness of the disinfection procedure with the intrinsic fluorescence instrument. Both the sample lenses after disinfection and the control lenses were immediately placed in LB broth for outgrowth and measured by standard cell-counting methods. The experiments were performed in triplicate. The concentration of P. aeruginosa formed on the lenses by the above methods varied from 10(6)-10(13) cells/mL. All lenses that were cultured following cleaning yielded no colonies. However, 10(5)-10(9) cells/mL of the bacteria on the treated lenses remained viable when analyzed by intrinsic fluorescence methodology. These results indicate that a medically significant amount of bacteria remained on the contact lenses after disinfection and/or cleaning, which were viable but nonculturable and are likely to go

  10. Generation of ozone foam and its application for disinfection

    NASA Astrophysics Data System (ADS)

    Hiragaki, Keisuke; Ishimaru, Tomiya; Nakanishi, Masaru; Muraki, Ryouji; Nieda, Masanori; Yamabe, Chobei

    2015-07-01

    Generated ozone foam was applied to the disinfection of Pseudomonas fluorescens. The effect of disinfection has been confirmed experimentally and new equipment for the disinfection of hands using this ozone foam has been put on the market for the practical use. The ozone foam was produced in the foam generator after mixing the water including surfactant (30 mL/min) and air including ozone (1000 ppm = 2.14 g/m3 ~ 1600 ppm = 3.4 g/m3, 300 mL/min). The liquid-to-gas ratio is 100 L/m3. The concentration of dissolved ozone in the thin liquid films of the bubbles was about 3 mg/L which was measured by the chemical method of the KI absorption and titration of sodium thiosulfate solution. The disinfection test samples were prepared using the PET disk on which Pseudomonas fluorescens of its number of more than 108 were attached. Test sample was inserted into ozone foam set on the glass plate for one to 6 min. The survival rate log (N/N0 decreased with time and its value of about-2.6 (i.e., ~1/400) was obtained at 6 min (2 min × 3 times repeated). It was also confirmed that the ozone foam was useful for the disinfection of hands. For more effective disinfection (in case of taking a long time for foam melting), the ozone foam was broken by force and changed into ozone water by which the survival rate decreased ×4 (i.e., N/N0 = 1/10 000) at 4 ~ 6 min. Contribution to the topical issue "The 14th International Symposium on High Pressure Low Temperature Plasma Chemistry (HAKONE XIV)", edited by Nicolas Gherardi, Ronny Brandenburg and Lars Stollenwark

  11. Evaluation of disinfectants commonly used by the commercial poultry industry under simulated field conditions.

    PubMed

    Stringfellow, K; Anderson, P; Caldwell, D; Lee, J; Byrd, J; McReynolds, J; Carey, J; Nisbet, D; Farnell, M

    2009-06-01

    The correct usage of disinfectants is an important component of a successful biosecurity program. The objective of this study was to determine the effect of time, temperature, and organic matter (OM) on disinfectant efficacy. Staphylococcus aureus and Salmonella Typhimurium were used to represent gram-negative and gram-positive bacteria commonly found in commercial poultry housing. The first study evaluated the effect of temperature (4, 20, 32, or 43 degrees C) and time (1, 2, 3, 4, 6, 8, 12, 16, 20, 24, and 30 wk) on the efficacy of disinfectants diluted to working concentrations. The second study determined the effect of OM on the efficacy of working concentrations of freshly prepared disinfectants against the bacteria. For the third study, we compared the bactericidal properties of freshly prepared disinfectants and 30-wk-old disinfectants in the presence of OM. Quaternary ammonium-, chlorhexidine-, phenolic-, and binary ammonium-based solutions represented disinfectants commonly used within the poultry industry. In the first study, all of the disinfectants were effective against S. aureus and Salmonella Typhimurium regardless of treatment. However, the phenolic compound had reduced (P disinfectants were effective against S. aureus regardless of temperature treatment. In the second study, the addition of sterile chicken litter had deleterious effects on all 4 classes of disinfectants against Salmonella Typhimurium. Of the disinfectants tested, the phenolic compound retained efficacy against S. aureus. In the third study, the presence of OM significantly reduced (P

  12. Estimating retrospective exposure of household humidifier disinfectants.

    PubMed

    Park, D U; Friesen, M C; Roh, H S; Choi, Y Y; Ahn, J J; Lim, H K; Kim, S K; Koh, D H; Jung, H J; Lee, J H; Cheong, H K; Lim, S Y; Leem, J H; Kim, Y H; Paek, D M

    2015-12-01

    We conducted a comprehensive humidifier disinfectant exposure characterization for 374 subjects with lung disease who presumed their disease was related to humidifier disinfectant use (patient group) and for 303 of their family members (family group) for an ongoing epidemiological study. We visited the homes of the registered patients to investigate disinfectant use characteristics. Probability of exposure to disinfectants was determined from the questionnaire and supporting evidence from photographs demonstrating the use of humidifier disinfectant, disinfectant purchase receipts, any residual disinfectant, and the consistency of their statements. Exposure duration was estimated as cumulative disinfectant use hours from the questionnaire. Airborne disinfectant exposure intensity (μg/m(3)) was estimated based on the disinfectant volume (ml) and frequency added to the humidifier per day, disinfectant bulk level (μg/ml), the volume of the room (m(3)) with humidifier disinfectant, and the degree of ventilation. Overall, the distribution patterns of the intensity, duration, and cumulative exposure to humidifier disinfectants for the patient group were higher than those of the family group, especially for pregnant women and patients ≤6 years old. Further study is underway to evaluate the association between the disinfectant exposures estimated here with clinically diagnosed lung disease. Retrospective exposure to household humidifier disinfectant as estimated here can be used to evaluate associations with clinically diagnosed lung disease due to the use of humidifier disinfectant in Korea. The framework, with modifications to account for dispersion and use patterns, can also be potentially adapted to assessment of other household chemical exposures. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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

    PubMed

    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.

  14. [Drinking water decontamination with isolative sorbent disinfectants].

    PubMed

    Krasnov, M S

    2004-01-01

    Drinking water can be decontaminated with the use of isolative sorbent disinfectants. Consideration of the effectiveness of water disinfectants and the sorptive power of porous materials against bacteria and viruses attested to the favour of iodine and silver-containing disinfectants and their compositions on porous aggressive carriers to be employed in extreme conditions such as on board crewed space vehicles.

  15. Disinfection of Human Teeth for Educational Purposes.

    ERIC Educational Resources Information Center

    Tate, William H.; White, Robert S.

    1991-01-01

    A study investigated the efficacy of glutaraldehyde and several other disinfectants for disinfecting teeth to be used for teaching and research, as an alternative to autoclaving for teeth with amalgam restorations. Results indicate that formalin was the only disinfectant that penetrated tooth pulp chambers in effective antimicrobial…

  16. Disinfection of Human Teeth for Educational Purposes.

    ERIC Educational Resources Information Center

    Tate, William H.; White, Robert S.

    1991-01-01

    A study investigated the efficacy of glutaraldehyde and several other disinfectants for disinfecting teeth to be used for teaching and research, as an alternative to autoclaving for teeth with amalgam restorations. Results indicate that formalin was the only disinfectant that penetrated tooth pulp chambers in effective antimicrobial…

  17. Implications of changing water cycle for the performance and yield characteristics of the multi-purpose Beas Reservoir in India

    NASA Astrophysics Data System (ADS)

    Adeloye, A. J.; Ojha, C. S.; Soundharajan, B.; Remesan, R.

    2013-12-01

    There is considerable change in both the spatial and temporal patterns of monsoon rainfall in India, with implications for water resources availability and security. 'Mitigating the Impacts of Climate Change on India Agriculture' (MICCI) is one of five on-going scientific efforts being sponsored as part of the UK-NERC/India-MOES Changing Water Cycle (South Asia) initiative to further the understanding of the problem and proffer solutions that are robust and effective. This paper focuses on assessing the implications of projected climate change on the yield and performance characteristics of the Pong Reservoir on the Beas River, Himachal Pradesh, India. The Pong serves both hydropower and irrigation needs and is therefore strategic for the socio-economic well-being of the region as well as sustaining the livelihoods of millions of farmers that rely on it for irrigation. Simulated baseline and climate-change perturbed hydro-climate scenarios developed as part of a companion Work Package of MICCI formed the basis of the analysis. For both of these scenarios, reservoir analyses were carried out using the Sequent Peak Algorithm (SPA) and Pong's existing level of releases to derive rule curves for the reservoir. These rule curves then formed the basis of further reservoir behaviour simulations in WEAP and the resulting performance of the reservoir was summarised in terms of reliability, resilience, vulnerability and sustainability. The whole exercise was implemented within a Monte Carlo framework for the benefit of characterising the variability in the assessments. The results show that the rule curves developed using future hydro-climate are significantly changed from the baseline in that higher storages will be required to be maintained in the Pong in the future to achieve reliable performance. As far as the overall performance of the reservoir is concerned, future reliability (both time-based and volume-based) is not significantly different from the baseline, provided

  18. Review of water disinfection techniques

    NASA Technical Reports Server (NTRS)

    Colombo, Gerald V.; Sauer, Richard L.

    1987-01-01

    Throughout the history of manned space flight the supply of potable water to the astronauts has presented unique problems. Of particular concern has been the microbiological quality of the potable water. This has required the development of both preflight water system servicing procedures to disinfect the systems and inflight disinfectant addition and monitoring devices to ensure continuing microbiological control. The disinfectants successfully used to date have been aqueous chlorine or iodine. Because of special system limitations the use of iodine has been the most successful for inflight use and promises to be the agent most likely to be used in the future. Future spacecraft potable, hygiene, and experiment water systems will utilize recycled water. This will present special problems for water quality control. NASA is currently conducting research and development to solve these problems.

  19. Review of water disinfection techniques

    NASA Technical Reports Server (NTRS)

    Colombo, Gerald V.; Sauer, Richard L.

    1987-01-01

    Throughout the history of manned space flight the supply of potable water to the astronauts has presented unique problems. Of particular concern has been the microbiological quality of the potable water. This has required the development of both preflight water system servicing procedures to disinfect the systems and inflight disinfectant addition and monitoring devices to ensure continuing microbiological control. The disinfectants successfully used to date have been aqueous chlorine or iodine. Because of special system limitations the use of iodine has been the most successful for inflight use and promises to be the agent most likely to be used in the future. Future spacecraft potable, hygiene, and experiment water systems will utilize recycled water. This will present special problems for water quality control. NASA is currently conducting research and development to solve these problems.

  20. Computational modeling of ultraviolet disinfection.

    PubMed

    Younis, B A; Yang, T H

    2010-01-01

    The efficient design of ultraviolet light (UV) systems for water and wastewater treatment requires detailed knowledge of the patterns of fluid motion that occur in the disinfection channel. This knowledge is increasingly being obtained using Computational Fluid Dynamics (CFD) software packages that solve the equations governing turbulent fluid-flow motion. In this work, we present predictions of the patterns of flow and the extent of disinfection in a conventional reactor consisting of an open channel with an array of UV lamps placed with their axes perpendicular to the direction of flow. It is shown that the resulting flow is inherently unsteady due to the regular shedding of vortices from the submerged lamps. It is also shown that the accurate prediction of the hydraulic residence time and, consequently, the extent of disinfection is strongly dependent on the ability of the CFD method to capture the occurrence and strength of the vortex shedding, and its effects on the turbulent mixing processes.

  1. Wettability, imbibition, and mass change of disinfected low-viscosity impression materials.

    PubMed

    Lepe, Xavier; Johnson, Glen H; Berg, John C; Aw, Tar C; Stroh, G Scott

    2002-09-01

    There is an ongoing effort by dental manufacturers to create impression materials with improved wetting properties. Disinfection solutions may alter the surface characteristics of these newer materials. This study compared wettability, imbibition, and mass change of various recently introduced automixed low-viscosity addition silicone and polyether materials before and after immersion disinfection. The Wilhelmy technique was used for deriving wetting properties of 5 addition silicone materials (Clinician's Choice Affinity, Clinician's Choice Superhydrophilic [experimental], Kerr's Take One, 3M's Imprint II, and Dentsply's Aquasil LV) and 2 polyether materials (ESPE's Permadyne Garant and Impregum Garant). Conditions included a control with no disinfection (0 hours), as well as (1/2) hour of immersion disinfection in a full-strength solution of 2% acid glutaraldehyde disinfectant (Banicide). Weight changes before and after disinfection and weight loss in air were measured over an 18-hour period to detect imbibition and mass change over time. The data were analyzed with a 1-way analysis of variance at alpha=0.05, with n = 3 for advancing (ACA) and receding (RCA) contact angles and n = 2 for imbibition and mass change. Statistical significant differences in wettability (P<.001) were found among nondisinfection control groups, as well as among (1/2)-hour disinfection groups. Polyethers were the most wettable materials overall. Impregum Garant polyether demonstrated significantly lower RCA for the control (48.4 degrees) and at (1/2) hour of disinfection (51.8 degrees). The 2 polyethers and Take One lost mass, whereas Aquasil LV gained mass in air; however, all materials exhibited some degree of imbibition during disinfection. Within the limitations of this study, the 2 polyether materials tested exhibited significantly lower ACA's and RCA's compared with the 5 addition silicones tested. Imbibition for the 2 polyether materials was significantly higher (P<.001

  2. Characterization of ozone disinfection of murine norovirus.

    PubMed

    Lim, Mi Young; Kim, Ju-Mi; Lee, Jung Eun; Ko, GwangPyo

    2010-02-01

    Despite the importance of human noroviruses (NoVs) in public health, little information concerning the effectiveness of ozone against NoVs is available. We determined the efficacy of ozone disinfection using murine norovirus (MNV) as a surrogate of human NoV. MNV in ozone demand-free buffer was exposed to a predetermined dose of ozone at two different pHs and temperatures. The virus remaining in the solution was analyzed by plaque assay, real-time TaqMan reverse transcriptase PCR (RT-PCR) (short template), and long-template conventional RT-PCR. Under all conditions, more than 99% of the MNV was inactivated by ozone at 1 mg/liter within 2 min. Both RT-PCR assays significantly underestimated the inactivation of MNV, compared with that measured by plaque assay. Our results indicate that NoV may be more resistant to ozone than has been previously reported. Nevertheless, proper ozone disinfection practices can be used to easily control its transmission in water.

  3. SU-E-J-47: Development of a High-Precision, Image-Guided Radiotherapy, Multi- Purpose Radiation Isocenter Quality-Assurance Calibration and Checking System

    SciTech Connect

    Liu, C; Yan, G; Helmig, R; Lebron, S; Kahler, D

    2014-06-01

    Purpose: To develop a system that can define the radiation isocenter and correlate this information with couch coordinates, laser alignment, optical distance indicator (ODI) settings, optical tracking system (OTS) calibrations, and mechanical isocenter walkout. Methods: Our team developed a multi-adapter, multi-purpose quality assurance (QA) and calibration device that uses an electronic portal imaging device (EPID) and in-house image-processing software to define the radiation isocenter, thereby allowing linear accelerator (Linac) components to be verified and calibrated. Motivated by the concept that each Linac component related to patient setup for image-guided radiotherapy based on cone-beam CT should be calibrated with respect to the radiation isocenter, we designed multiple concentric adapters of various materials and shapes to meet the needs of MV and KV radiation isocenter definition, laser alignment, and OTS calibration. The phantom's ability to accurately define the radiation isocenter was validated on 4 Elekta Linacs using a commercial ball bearing (BB) phantom as a reference. Radiation isocenter walkout and the accuracy of couch coordinates, ODI, and OTS were then quantified with the device. Results: The device was able to define the radiation isocenter within 0.3 mm. Radiation isocenter walkout was within ±1 mm at 4 cardinal angles. By switching adapters, we identified that the accuracy of the couch position digital readout, ODI, OTS, and mechanical isocenter walkout was within sub-mm. Conclusion: This multi-adapter, multi-purpose isocenter phantom can be used to accurately define the radiation isocenter and represents a potential paradigm shift in Linac QA. Moreover, multiple concentric adapters allowed for sub-mm accuracy for the other relevant components. This intuitive and user-friendly design is currently patent pending.

  4. New disinfection and sterilization methods.

    PubMed Central

    Rutala, W. A.; Weber, D. J.

    2001-01-01

    New disinfection methods include a persistent antimicrobial coating that can be applied to inanimate and animate objects (Surfacine), a high-level disinfectant with reduced exposure time (ortho-phthalaldehyde), and an antimicrobial agent that can be applied to animate and inanimate objects (superoxidized water). New sterilization methods include a chemical sterilization process for endoscopes that integrates cleaning (Endoclens), a rapid (4-hour) readout biological indicator for ethylene oxide sterilization (Attest), and a hydrogen peroxide plasma sterilizer that has a shorter cycle time and improved efficacy (Sterrad 50). PMID:11294738

  5. Effect of mixing techniques on bacterial attachment and disinfection time of polyether impression material

    PubMed Central

    Guler, Umut; Budak, Yasemin; Ruh, Emrah; Ocal, Yesim; Canay, Senay; Akyon, Yakut

    2013-01-01

    Objective: The aim of this study was 2-fold. The first aim was to evaluate the effects of mixing technique (hand-mixing or auto-mixing) on bacterial attachment to polyether impression materials. The second aim was to determine whether bacterial attachment to these materials was affected by length of exposure to disinfection solutions. Materials and Methods: Polyether impression material samples (n = 144) were prepared by hand-mixing or auto-mixing. Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were used in testing. After incubation, the bacterial colonies were counted and then disinfectant solution was applied. The effect of disinfection solution was evaluated just after the polymerization of impression material and 30 min after polymerization. Differences in adherence of bacteria to the samples prepared by hand-mixing and to those prepared by auto-mixing were assessed by Kruskal-Wallis and Mann-Whitney U-tests. For evaluating the efficiency of the disinfectant, Kruskal-Wallis multiple comparisons test was used. Results: E. coli counts were higher in hand-mixed materials (P < 0.05); no other statistically significant differences were found between hand- and auto-mixed materials. According to the Kruskal-Wallis test, significant differences were found between the disinfection procedures (Z > 2.394). Conclusion: The methods used for mixing polyether impression material did not affect bacterial attachment to impression surfaces. In contrast, the disinfection procedure greatly affects decontamination of the impression surface. PMID:24966729

  6. [Disinfection of caliciviruses at 20 and 10 degrees C].

    PubMed

    Yilmaz, A; Kaleta, E F

    2003-07-01

    Five disinfectants, Venno FF super, Venno Vet 1 super, Venno Oxygen, M&Enno-Veterinär B neu und Neopredisan 135-1, were tested to evaluate their efficacy against caliciviruses at 20 and 10 degrees C. As model test virus served feline calicivirus type F9 (FCV F9). All disinfectants were tested according to Guidelines of the German Veterinary Association (DVG). The investigations were performed in suspension tests and germ carrier tests. The suspension tests were carried out without and with protein load. As protein was used foetal calf serum at the concentration of 40%. Venno FF super showed less protein dependence, however a considerable temperature dependence. This matter can be corrected by increase of concentration on 2%. Venno Vet 1 super was without protein especially effective. The losses on the effectiveness through low temperature and protein load can be annulled also here by increase of concentration. Venno Oxygen was more effective in the comparison to that here named both preparations. The effects of temperature can be corrected by extension of reaction time. The most effective preparation was M&Enno Veterinär B neu. The disinfection occurred at 20 degrees C with 0.5% solution within 120 min and at 10 degrees C with 1.0% solution within 60 min. The fifth disinfectant Neopredisan was in suspension tests without protein load and carrier tests with gauze at 20 and 10 degrees C relative convincing but in germ carrier tests with poplar wood, no complete disinfection could be achieved within tested concentrations and reaction times.

  7. EPIDEMIOLOGIC STUDIES OF DISINFECTANTS AND DISINFECTANT BY-PRODUCTS

    EPA Science Inventory

    This article provides a review of the epidemiologic evidence for human health effects that may be associated with the disinfection of drinking water. An epidemiologic study attempts to link human health effects with exposure to a specific agent (e.g., DBCM), agents (e.g., THMs or...

  8. A new method for photodynamic disinfection of prosthetic constructions and impressions in prosthetic dentistry.

    PubMed

    Vlahova, Angelina P; Kisov, Christo K; Popova, Elka V; Haydushka, Irina A; Mantareva, Vanya N

    2012-01-01

    Photodynamic therapy is a topical treatment of pathogens that involves the use of a photoactive dye (photosensitizer), which is non-toxic when not exposed to light and activated by light of a specific wavelength in the presence of oxygen. The highly cytotoxic oxygen species generated by the induced photophysical processes inactivate the pathogenic cells. The PURPOSE of this study was to present a new method we developed for photodynamic disinfection of prostheses and impressions in prosthetic dentistry and to assess its effectiveness in comparison with some conventional methods of disinfection. The method was developed on the basis of series of experimental studies (30 experiments for each type of disinfectant, 30 controls with no disinfection for each material, and 30 direct cultures of each test microorganism--MRSA, P. aeruginosa and C. albicans) using standard test specimens made of prosthesis plastic and impression materials. The new method of photodynamic disinfection with GaPc1 as photosensitizer was 100% efficient in C-silicones, A-silicones and polyethers, but not in alginates (40%). To plastics the photodynamic method shows the same efficiency as the conventional disinfectants of hypochlorite solutions and denture cleansing tablets (100% effect). The method of photodynamic disinfection we developed is a good therapeutic choice against orally transmitted diseases in prosthetic dentistry.

  9. Disinfection effectiveness of slightly acidic electrolysed water in swine barns.

    PubMed

    Hao, X X; Li, B M; Zhang, Q; Lin, B Zh; Ge, L P; Wang, C Y; Cao, W

    2013-09-01

    To evaluate the disinfection effectiveness of slightly acidic electrolysed water (SAEW, pH 6·25-6·53), a new environmental friendly agent for inactivating micro-organisms adhered to the facility and aerosolized in the air of the swine barns and to explore the application of SAEW in livestock industries. Bacteria and fungi were isolated from the swine house air and treated by SAEW. The SAEW solution was flushed onto surfaces and sprayed within the whole swine barn. SAEW with an available chlorine concentration (ACC) of 300 mg l(-1) can inhibit isolated microbes completely. The usage of SAEW (300 mg l(-1) ) resulted in a significant (P < 0·05) reduction in microbes on the wall, rail and floor after flushing disinfection. Additionally, spraying SAEW at an ACC of 300 mg l(-1) reduced 59% of the airborne organisms in 30 min and kept the population of microbes at a reduced level for at least 8 h. SAEW treatment also reduced pathogens on surfaces (P < 0·03) after spraying disinfection except on the surface of the wall. SAEW may be a potential alternative disinfectant to reduce infections in swine barns. The results of this study provide information on the antimicrobial efficiency of SAEW on the airborne bacteria and fungi in swine barns. © 2013 The Society for Applied Microbiology.

  10. Assessment of peracetic acid disinfected effluents by microbiotests.

    PubMed

    Antonelli, M; Mezzanotte, V; Panouillères, M

    2009-09-01

    Bioassays were performed by commercially available kits on peracetic acid (PAA) solutions, at different concentrations, and on secondary effluents (from two different wastewater treatment plants) after disinfection at bench-scale, considering both samples containing residual active PAA and the same samples where residual PAA was quenched. Four indicator organisms were used: Vibrio fischeri, Thamnocephalus platyurus, Daphnia magna, and Selenastrum capricornutum. The experiments lead to conclude that Thamnocephalus platyurus is a very sensitive organism, probably not adequate to perform a reliable toxicity assessment of effluents for monitoring purposes. The presence of specific organic compounds deriving from human metabolism and urban pollution, even at very low concentrations, can affect the results of bioassays, especially those performed on Vibrio fischeri. PAA is toxic for bacteria and crustaceans even at concentrations lower than the ones commonly used in wastewater disinfection (2-5 mg/L), while its effect on algae is smaller. The toxic effect on bacteria was expected, as PAA is used for disinfection, but its possible influence on biological processes in the receiving aquatic environment should be considered. Toxicity on crustaceans would confirm the fact that discharging disinfected effluents could raise some environmental problems.

  11. Origin of disinfection by-products in cheese.

    PubMed

    Cardador, Maria Jose; Gallego, Mercedes; Prados, Francisco; Fernández-Salguero, José

    2017-06-01

    The disinfection of water, equipment and surfaces in a cheese factory is one of the factors that can originate disinfection by-products (DBPs) in cheese. This research has focused on studying cheese factories in order to evaluate the individual contribution of each step of the cheese-making process that can contribute to the presence of DBPs in cheese. Ten factories were selected according to their salting processes (brine or dry salting). Each factory was monitored by the collection of six representative samples (factory water supply, brine solution, milk, whey, curd and cheese) in which the concentrations of up to eight chemicals were detected. The study shows that contact with brine solutions containing significant levels of DBPs is the main source of these chemicals in cheese. A minor factor is the pasteurised milk used in their manufacture.

  12. Shear bond strength of composite resin to dentin after application of cavity disinfectants – SEM study

    PubMed Central

    Sharma, Vivek; Rampal, Poonam; Kumar, Sukesh

    2011-01-01

    Aim: The aim was to evaluate the effect of different cavity disinfectants on dentin bond strengths of composite resin applied with two different adhesive systems. Materials and Methods: Two-hundred mandibular molars were sectioned parallel to the occlusal surface to expose dentin in the midcoronal one-third. The dentinal surfaces were polished with waterproof-polishing papers. The specimens were randomly divided into five groups of 40 teeth each as follows: group 1(control) -- specimens were not treated with any cavity disinfectants. Groups 2--5 (experimental groups) -- dentin surfaces were treated with the following cavity disinfectants, respectively; 2% chlorhexidine solution, 0.1% benzalkonium chloride-based disinfectant, 1% chlorhexidine gel, and an iodine potassium iodide/copper sulfate-based disinfectant. The specimens were then randomly divided into two subgroups including 20 teeth each to evaluate the effect of different bonding systems. Dentin bonding systems were applied to the dentin surfaces and the composite buildups were done. After the specimens were stored in an incubator for 24 hours, the shear bond strength was measured at a crosshead speed of 1 mm/min. The specimens were then statistically analyzed. Statistical Analysis Used: One way analysis of variance and Tukey-HSD tests were used. Results: There was no significant difference between chlorhexidine gel and control groups regardless of the type of the bonding agent used (P>0.05). On the other hand, pretreatment with benzalkonium chloride-based, iodine potassium iodide/copper sulfate-based disinfectants or chlorhexidine solutions had a negative effect on the shear bond strength of self-etching bonding systems. Conclusions: The findings of this study suggest that when benzalkonium chloride-based, iodine potassium iodide/copper sulfate-based disinfectants or chlorhexidine solutions are used as a cavity disinfectant, an etch-and-rinse bonding system should be preferred. PMID:22090756

  13. Colour stability of relined dentures after chemical disinfection. A randomised clinical trial.

    PubMed

    Moffa, Eduardo Buozi; Giampaolo, Eunice Teresinha; Izumida, Fernanda Emiko; Pavarina, Ana Cláudia; Machado, Ana Lúcia; Vergani, Carlos Eduardo

    2011-12-01

    This randomised clinical study evaluated the effect of chemical disinfection with sodium perborate or chlorhexidine on the colour stability of a hard chairside reline resin during six months. Hard chairside reline resin (Tokuyama Rebase Fast II) was used to reline complete dentures. After baseline colour measurements, the patients were randomly divided into 3 groups (n = 15) and allocation was concealed with the use of the BioStat program. The dentures were cleansed according to three methods: CG (control group)--brushing with coconut soap and soft toothbrush, PG (Perborate group)--brushing according to previous methods and disinfection with warmed sodium perborate solution (Corega Tabs) for 5 min, once a day for 6 months and ChxG (Chlorhexidine Group)--brushing according to CG and disinfection with chlorhexidine digluconate 2% for 5min once a day for 6 months. The data of ΔE*, ΔL*, Δa* and Δb* were analysed by 2-way repeated-measures ANOVAs and Tukey tests (α = 0.05). There were significant differences amongst groups for ΔL, Δa and Δb. The time had a significant effect on ΔE and ΔL, for all groups evaluated. Changes in some colour parameters (ΔL, Δa and Δb) of the reline resin Tokuyama Rebase were observed when the dentures were disinfected by perborate and chlorhexidine digluconate 2% solutions. The colour stability of was also influenced by time, regardless of disinfection or nondisinfection. Colour stability of the denture materials is one variable to be considered when choosing disinfection methods. The data in this study will be useful to clinicians when they are selecting disinfectant solutions for disinfection of relined denture. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Effect of iodine disinfectant source and water quality parameters on soluble iodine speciation

    NASA Technical Reports Server (NTRS)

    Silverstein, Joann; Hurst, Charles; Barkley, Robert; Dunham, Andrew

    1993-01-01

    Investigations of iodine species distribution of various aqueous solutions of iodine disinfectants and water from equilibrated suspensions of triodide and pentaiodide resins were done at the University of Colorado for the Center for Space Environmental Health during 1992 and 1993. Direct measurements of three individual iodine species: I(-), I2 and I3(-), were made. In addition three measures of total titratable iodine species were used. It has been found that I2 and I3(-) solutions produce a significant fraction of the non-disinfecting species iodine I(-), ranging from 50 to 80% of added iodine, respectively, at pH values of approximately 5. Correspondingly, I2 solutions produce more than twice the concentration of disinfecting iodine species per mass iodine dose than I3(-) solutions. Both I(-) and I2 species were found in aqeuous extracts of pentaiodide resin, although no soluble species were detected with triiodide resin.

  15. Effect of iodine disinfectant source and water quality parameters on soluble iodine speciation

    NASA Technical Reports Server (NTRS)

    Silverstein, Joann; Hurst, Charles; Barkley, Robert; Dunham, Andrew

    1993-01-01

    Investigations of iodine species distribution of various aqueous solutions of iodine disinfectants and water from equilibrated suspensions of triodide and pentaiodide resins were done at the University of Colorado for the Center for Space Environmental Health during 1992 and 1993. Direct measurements of three individual iodine species: I(-), I2 and I3(-), were made. In addition three measures of total titratable iodine species were used. It has been found that I2 and I3(-) solutions produce a significant fraction of the non-disinfecting species iodine I(-), ranging from 50 to 80% of added iodine, respectively, at pH values of approximately 5. Correspondingly, I2 solutions produce more than twice the concentration of disinfecting iodine species per mass iodine dose than I3(-) solutions. Both I(-) and I2 species were found in aqeuous extracts of pentaiodide resin, although no soluble species were detected with triiodide resin.

  16. Postoutbreak disinfection of mobile equipment.

    PubMed

    Alphin, R L; Ciaverelli, C D; Hougentogler, D P; Johnson, K J; Rankin, M K; Benson, E R

    2010-03-01

    Current control strategies for avian influenza virus, exotic Newcastle disease, and other highly contagious poultry diseases include surveillance, quarantine, depopulation, disposal, and decontamination. Skid steer loaders and other mobile equipment are extensively used during depopulation and disposal. Movement of contaminated equipment has been implicated in the spread of disease in previous outbreaks. One approach to equipment decontamination is to power wash the equipment, treat with a liquid disinfectant, change any removable filters, and let it sit idle for several days. In this project, multiple disinfectant strategies were individually evaluated for their effectiveness at inactivating Newcastle disease virus (NDV) on mechanical equipment seeded with the virus. A small gasoline engine was used to simulate typical mechanical equipment. A high titer of LaSota strain, NDV was applied and dried onto a series of metal coupons. The coupons were then placed on both interior and exterior surfaces of the engine. Liquid disinfectants that had been effective in the laboratory were not as effective at disinfecting the engine under field conditions. Indirect thermal fog showed a decrease in overall virus titer or strength. Direct thermal fog was more effective than liquid spray application or indirect thermal fog application.

  17. Recycled Water Poses Disinfectant Problem

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1973

    1973-01-01

    Discusses the possible health hazards resulting from released nucleic acid of inactivated viruses, chlorinated nonliving organic molecules, and overestimated reliability of waste treatment standards. Suggests the recycle system use a dual disinfectant such as chlorine and ozone in water treatment. (CC)

  18. Recycled Water Poses Disinfectant Problem

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1973

    1973-01-01

    Discusses the possible health hazards resulting from released nucleic acid of inactivated viruses, chlorinated nonliving organic molecules, and overestimated reliability of waste treatment standards. Suggests the recycle system use a dual disinfectant such as chlorine and ozone in water treatment. (CC)

  19. The Multi-Purpose Astrolabe.

    ERIC Educational Resources Information Center

    Neie, Van E.

    1979-01-01

    Directions are given for construction of an astrolabe capable of yielding two celestial coordinates: altitude and azimuth. Potential uses are included for both young and older children. Quantitative measurement activities related to celestial motion and position are given. (SA)

  20. Armored Multi Purpose Vehicle (AMPV)

    DTIC Science & Technology

    2015-12-01

    AMPV shall prevent a sustained fuel fire when fuel container(s) are exposed to the RPG , IED, and EFP threats and conditions specified in Table 6.1...Miles Per Hour NET - New Equipment Training O - Objective OMS/MP - Operational Mode Summary/Mission Profile RPG - Rocket Propelled Grenade SA - System

  1. The effect of disinfectant agents on dimensional stability and surface roughness of a tissue conditioner material.

    PubMed

    Khaledi, Amiralireza; Borhanihaghighi, Zohre; Vojdani, Mahroo

    2011-01-01

    The aim of this study was to determine the effect of disinfectant procedures on the dimensional stability and surface quality of a tissue conditioner used as a functional impression material. A tissue conditioner (Visco-gel) used as a functional impression material was disinfected by immersion in 5.25% sodium hypochlorite or 2% glutaraldehyde solutions for 10 or 20 minutes, respectively. The control group consisted of specimens (n=10) that were not treated by disinfectants. For testing the dimensional stability, impressions of an aluminum edentulous arch with three reference points were made. After 24 hours of storage in distilled water, the specimens were treated by one of the disinfection procedures. Impressions were poured and, subsequently, 50 stone casts were measured with a Nikon profile projector. For surface roughness evaluation, disks that contained Visco-gel were pressed against glass slides. The disks were then stored in distilled water for 24 hours. After disinfection, 50 disk-shaped dental stone casts were prepared. Surface roughness values were determined using a profilometer. For each test, data were subjected to two-way analysis of variance (ANOVA) followed by Tukey's test (α = 0.05). The results of the dimensional stability test showed that immersion of Visco-gel impressions in 5.25% sodium hypochlorite solution or 2% glutaraldehyde solution did not significantly change the anteroposterior (AP) and cross-arch (CA) distances of the resultant stone casts when compared to the control group (P>0.05). The surface quality of dental stone casts formed by Visco-gel did not change significantly when impressions were immersed in the disinfectant solutions for either 10 or 20 minutes, or when stored in distilled water (P>0.05). The results showed that the disinfectant solutions used in this study did not have a significant effect on the surface quality and dimensional accuracy of Visco-gel as a functional impression material.

  2. Waterborne outbreak control: which disinfectant?

    PubMed

    Akin, E W; Hoff, J C; Lippy, E C

    1982-12-01

    Drinking water disinfection was shown to be an important public health measure around the turn of the century. In the United States, it was perhaps the single most important factor in controlling typhoid fever, a waterborne disease that was rampant throughout the world during the last century. It may also be assumed that disinfection was important in limiting the number of cases of other diseases known to be capable of waterborne transmission, i.e., cholera, amebiasis, shigellosis, salmonellosis, and hepatitis A. Even though modern treatment has eliminated water as a major vehicle of infectious disease transmission, outbreaks still occur. In fact, the annual number has been increasing since 1966. Interruption in chlorination or failure to achieve adequate levels of chlorine residual is the most often identified deficiency of the involved water supplies. This finding indicates that waterborne microbial pathogens remain as a potential health threat and underscores the importance of disinfection. From the outset, chlorination has been the drinking water disinfectant of choice in the country. Numerous studies have demonstrated its ability to inactivate bacterial, viral, and protozoal pathogens when applied under proper conditions. However, the finding that chlorinated organics that are potentially carcinogenic are formed has prompted an evaluation of alternative disinfectants. The viable alternatives to chlorine currently under consideration for widespread use are ozone, chlorine dioxide, and chloramines. In terms of biocidal efficiency, ozone is the most potent of the three. Chlorine dioxide is about the equivalent of free chlorine in the hypochlorous acid form but much more efficient than the hypochlorite form of free chlorine. The chloramines are weaker biocides than hypochlorite. Although this general order of ranking of efficiency holds for diverse types of microorganisms, quantitative comparisons vary with different microorganisms and experimental conditions.

  3. Disinfection of the Skin: An Assessment of Some New Preparations

    PubMed Central

    Lilly, H. A.; Lowbury, E. J. L.

    1971-01-01

    Repeated hand washing with a detergent solution containing 0·75% chlorhexidine digluconate was found to cause a large reduction in the resident skin flora which was slightly though significantly smaller than that caused by the use of 3% hexachlorophane liquid soap containing a phenolic preservative, chlorocresol 0·3%. Both agents caused a greater immediate reduction of bacteria after a single hand washing than the hexachlorophane liquid soap without a phenolic additive had shown in earlier experiments; the soap base containing chlorocresol 0·3% but no hexachlorophane was also found to cause a large reduction in skin flora. The chlorhexidine detergent solution had no residual disinfectant action on the skin after rinsing and drying the hands. Disinfection of an operation site for two minutes with povidone-iodine containing 1% available iodine in 70% ethyl alcohol caused about as great a reduction in resident flora as a similar treatment with alcoholic 0·5% chlorhexidine. Both treatments were more effective than disinfection with aqueous 1% cetrimide or 0·1% benzalkonium chloride solutions. PMID:5569550

  4. Effect of chemical and microwave disinfection on the surface microhardness of acrylic resin denture teeth.

    PubMed

    Vasconcelos, Ligia Regina; Consani, Rafael Leonardo Xediek; Mesquita, Marcelo Ferraz; Sinhoreti, Mário Alexandre Coelho

    2013-06-01

    The purpose of this study was to evaluate the effect of simulated disinfections (2% glutaraldehyde, 1% sodium hypochlorite, and microwave energy) on the surface hardness of Trilux, Biocler, Biotone, New Ace, and Magister commercial artificial teeth. Specimens (n = 10) were made with the teeth included individually in circular blocks of acrylic resin, leaving the labial surface exposed. Cycles of simulated chemical disinfection were accomplished with the specimens immersed in the solutions at room temperature for 10 minutes, followed by tap water washing for 30 seconds and storage in distilled water at room temperature for 7 days until the next disinfection. Simulated disinfection by microwave energy was carried out in a domestic oven with 1300 W at a potency of 50% for 3 minutes with the specimens individually immersed in 150 ml of distilled water. Control (no disinfection) and the experimental groups (first and third disinfection cycles) were submitted to Knoop hardness measurements with indentations at the center of the labial tooth surface. Data were submitted to repeated measure two-way ANOVA and Tukey's test (α = 0.05). Biocler, Magister, and Trilux showed lower surface microhardness when submitted to microwave. Lower microhardness for Biotone was promoted by hypochlorite, while no significant difference was shown for New Ace. The third disinfection cycle significantly decreased the tooth surface hardness only for microwave. Different disinfection methods promoted different effects on the microhardness of different types of artificial teeth. Surface microhardness of the teeth was less affected by the simulated chemical disinfections when compared to microwaved specimens. © 2013 by the American College of Prosthodontists.

  5. Factors in the Selection of Surface Disinfectants for Use in a Laboratory Animal Setting

    PubMed Central

    Campagna, Michael V; Faure-Kumar, Emmanuelle; Treger, Janet A; Cushman, Jesse D; Grogan, Tristan R; Kasahara, Noriyuki; Lawson, Gregory W

    2016-01-01

    Because surface disinfectants are an important means of pathogen control within laboratory animal facilities, these products must have an appropriate spectrum of antimicrobial activity. However, many other factors must also be considered, including effects on human health, environmental safety, and animal behavior. Aqueous solutions of sodium hypochlorite often are considered to be the ‘gold standard’ for surface disinfection, but these products can be corrosive, caustic, and aversive in odor. This study was designed to identify disinfectants that are as effective as hypochlorite solutions but more acceptable for use in a laboratory animal setting. An antiviral disinfectant-efficacy assay was developed by using viral vectors that expressed green fluorescence protein as surrogates for wild-type viruses of concern in laboratory animals. Efficacy testing revealed that most of the products were highly effective when used against viral vectors in suspension. However, when the disinfectants were challenged by buffering virus in protein or drying virus on nonporous surfaces, the hypochlorite and peroxymonosulfate products performed the best. Review of safety data sheets for the agents indicated that a peroxide-based product was considerably safer than the other products tested and that the pH of most products was not conducive to disposal down a drain. Behavioral testing of Swiss Webster, C57Bl/6, and BALB/c mice showed that the hypochlorite- and peroxide-based products were clearly aversive, given that the mice consistently avoided these products. All of these factors must be considered when choosing the appropriate disinfectant. PMID:27025810

  6. Disinfection of gutta-percha cones using three reagents and their residual effects

    PubMed Central

    Chandrappa, Mahesh Martur; Mundathodu, Nofal; Srinivasan, Raghu; Nasreen, Farhat; Kavitha, Pamarthi; Shetty, Ashwija

    2014-01-01

    Aims and Objectives: The purpose of this study was to compare the efficacy of 5.25% sodium hypochlorite, 2% chlorehexidine and MTAD in disinfecting gutta-percha cones and to analyze the surface topography of gutta-percha cones after the rapid chemical disinfection procedure. Materials and Methods: Gutta-percha cones were immersed in suspensions of Enterococcus faecalis and Staphylococcus aureus separately. The cones were then immersed in 5.25% NaOCl, 2% CHX and MTAD for 30 seconds, 1 minute and 5 minutes separately. The disinfected cones were then incubated in thioglycollate media for 7 days. The thioglycolate media was sub-cultured and colony forming units were counted. For topographical examination of gutta-percha cones, the cones were immersed in respective solutions for one minute and allowed to air dry for 30 minutes after rinsing or without rinsing the cones with distilled water. The topography of the cones were then analyzed under SEM. Data was statistically analyzed using one way anova. Results: MTAD was found to be the most effective disinfecting solution. The topographical examination of GP cones found some deposits after the disinfection procedure in every group. These deposits were removed when the GP cones were rinsed with distilled water. Conclusions: MTAD possesses superior bactericidal activity when compared with NaOCl and CHX and a final rinse with distilled water is essential after the disinfection procedure. PMID:25506147

  7. Factors in the Selection of Surface Disinfectants for Use in a Laboratory Animal Setting.

    PubMed

    Campagna, Michael V; Faure-Kumar, Emmanuelle; Treger, Janet A; Cushman, Jesse D; Grogan, Tristan R; Kasahara, Noriyuki; Lawson, Gregory W

    2016-03-01

    Because surface disinfectants are an important means of pathogen control within laboratory animal facilities, these products must have an appropriate spectrum of antimicrobial activity. However, many other factors must also be considered, including effects on human health, environmental safety, and animal behavior. Aqueous solutions of sodium hypochlorite often are considered to be the 'gold standard' for surface disinfection, but these products can be corrosive, caustic, and aversive in odor. This study was designed to identify disinfectants that are as effective as hypochlorite solutions but more acceptable for use in a laboratory animal setting. An antiviral disinfectant-efficacy assay was developed by using viral vectors that expressed green fluorescence protein as surrogates for wild-type viruses of concern in laboratory animals. Efficacy testing revealed that most of the products were highly effective when used against viral vectors in suspension. However, when the disinfectants were challenged by buffering virus in protein or drying virus on nonporous surfaces, the hypochlorite and peroxymonosulfate products performed the best. Review of safety data sheets for the agents indicated that a peroxide-based product was considerably safer than the other products tested and that the pH of most products was not conducive to disposal down a drain. Behavioral testing of Swiss Webster, C57Bl/6, and BALB/c mice showed that the hypochlorite- and peroxide-based products were clearly aversive, given that the mice consistently avoided these products. All of these factors must be considered when choosing the appropriate disinfectant.

  8. Effectiveness of chemical disinfection on biofilms of relined dentures: A randomized clinical trial.

    PubMed

    Moffa, Eduardo B; Izumida, Fernanda E; Jorge, Janaina H; Mussi, Maria C M; Siqueira, Walter L; Giampaolo, Eunice T

    2016-02-01

    To evaluate the effect of disinfection with sodium perborate or chlorhexidine (when combined with brushing) on the removal of biofilm in relined dentures. Swabs were collected 48 hours after the relining procedure and at the follow-up time intervals of 7, 15, 30, 90, and 180 days. The dentures' surface roughness was measured at the same times. 45 subjects were randomly divided into three groups of 15 subjects each. The control group brushed with coconut soap and a soft toothbrush. The sodium perborate group followed the same procedure and also disinfected with sodium perborate solution for 5 minutes per day. The chlorhexidine group followed the control group procedure and disinfected with 2% chlorhexidine digluconate solution for 5 minutes per day. The number of colony forming units and the surface roughness were evaluated statistically by 2-way repeated-measure ANOVA (α = 0.05). The control group dentures exhibited similar levels of microbial cells throughout the experiment. However, after 15 days, no microbial growth was observed on the dentures for which either disinfection agent was used. There were no statistically significant differences in superficial roughness between the groups (P = 0.298). The disinfection agents used, combined with brushing, were able to remove the relined dentures' biofilm after 15 days of disinfection. Roughness was not a predominant factor in CFU reduction.

  9. [Influence of different methods of chemical disinfection on the physical properties of type IV and V gypsum dies].

    PubMed

    Soares, C R; Ueti, M

    2001-01-01

    Several instruments and materials frequently used in prosthodontics--such as stone casts, dental impressions, interocclusal records--are classified, by the dental literature, as vehicles of transmission of infectious diseases to those who handle them. The present study aims at comparing dimensional alteration, superficial texture and compression resistance of stone dies submitted to different disinfection methods: 30-minute immersion in 1% sodium hypochlorite or in 2.2% alkaline glutaraldehyde (with or without previous ultrasonic washing) and addition of 2.2% alkaline glutaraldehyde or 5% sodium hypochlorite to the gypsum during its preparation. It was possible to conclude that: (1) chemical disinfection did not cause significant dimensional alteration in stone dies; (2) superficial texture was altered according to the disinfection method utilized; (3) immersion in disinfectant solution during 30 min, as well as the addition of disinfectant to the gypsum during its preparation, reduced the compression resistance of dies.

  10. The effect of chlorine-based disinfectant on wettability of a vinyl polysiloxane impression material.

    PubMed

    Blalock, John S; Cooper, Jeril R; Rueggeberg, Frederick A

    2010-11-01

    Extended contact of impression materials with chemical disinfectant could remove surfactant, significantly altering the contact angle and wettability characteristics of an impression material. The purpose of this study was to determine the effect of contact time of chemical disinfectant solution on the dynamic contact angle of a commercial vinyl polysiloxsane impression material. Discs (3.5 × 25 mm) of heavy-body and wash consistencies of material (n=5) were fabricated and either left untreated, or subjected to spray treatment with a commercial disinfectant for various lengths of time (1, 20, or 60 minutes, or 24 hours). Treated specimens were washed and dried, after which dynamic contact angle measurements of a water droplet were determined at various points in time after deposition: 0, 2, 5, 10, 15, and 20 seconds. The same wash product was used without added surfactant (control). For a given type of impression material, contact angles were subjected to 1-way ANOVA within each droplet deposition time for all periods of disinfectant contact (α=.05). The Tukey-Kramer post hoc test was applied for pairwise means comparisons. For each impression material type, significant increases in contact angles were found as the duration of disinfectant contact increased, at each measured droplet deposition time point. For both materials containing surfactant, extended contact with chemical disinfectant resulted in increased contact angles that were not significantly different from those of the nonsurfactant-containing control product. Increasing the contact time between a surfactant-containing impression material and a disinfecting solution can significantly alter the resulting contact angle of the impression material and render it similar to a material depleted of surfactant. Following manufacturer-recommended chemical disinfection times reduces surfactant loss and only minimally affects surface wettability. Copyright © 2010 The Editorial Council of the Journal of

  11. Comparison of disinfection byproduct formation from chlorine and alternative disinfectants.

    PubMed

    Hua, Guanghui; Reckhow, David A

    2007-04-01

    Seven diverse natural waters were collected and treated in the laboratory under five oxidation scenarios (chlorine, chloramine, both with and without preozonation, and chlorine dioxide). The impact of these disinfectants on the formation of disinfection byproducts was investigated. Results showed that preozonation decreased the formation of trihalomethanes (THMs), haloacetic acids (HAAs) and total organic halogen (TOX) for most waters during postchlorination. A net increase in THMs, HAAs and TOX was observed for a water of low humic content. Either decreases or increases were observed in dihaloacetic acids and unknown TOX (UTOX) as a result of preozonation when used with chloramination. Chloramines and chlorine dioxide produced a higher percentage of UTOX than free chlorine. They also formed more iodoform and total organic iodine (TOI) than free chlorine in the presence of iodide. Free chlorine produced a much higher level of total organic chlorine (TOCl) and bromine (TOBr) than chloramines and chlorine dioxide in the presence of bromide.

  12. The role and fate of inorganic nitrogen species during UVA/TiO₂ disinfection.

    PubMed

    Zuo, XiaoJun; Hu, Jiangyong; Chen, MinDong

    2015-09-01

    Inorganic nitrogen species have three states including ammonia nitrogen (NH4(+)/NH3), nitrite (NO2(-)) and nitrate (NO3(-)) and are often found in the disinfection system. However, no available literature could be found on their role and fate in photocatalytic disinfection systems. In this study, batch experiments were conducted to investigate bacteria inactivation, H2O2 generated and inorganic nitrogen variation to understand the role and fate of inorganic nitrogen species during UVA/TiO2 disinfection and evaluate effects of initial pH and bacteria levels on the role and fate. NH4(+)/NH3 and NO2(-) inhibited the photocatalytic disinfection process obviously. It could be confirmed through that H2O2 yield used for pathogen inactivation was dependent on NH4(+)/NH3 and NO2(-) levels. The NH4(+)/NH3 remaining, NH4(+) remaining and NO3(-) yields in only NH4(+)/NH3 photocatalytic oxidation experiments were obviously different from the corresponding values in the photocatalytic disinfection experiments with NH4(+)/NH3, which confirmed that photocatalytic disinfection had an obvious effect on the fate of NH4(+)/NH3. However, photocatalytic disinfection had slight effects on the fate of NO2(-) and NO3(-). Escherischia coli inactivation rate was the highest in neutral solutions (Initial pH 7) while the lowest in alkaline solutions (Initial pH 8.5). The decrease of NH4(+)/NH3 in alkaline solutions was the most significant. In turn, the photocatalysis of NO2(-) was more evident in acidic solutions. E. coli inactivation was reduced with the increase of initial E. coli concentrations. The initial bacteria concentrations significantly influenced the increase of NH4(+)/NH3, NH4(+) and NO3(-), but slightly impacted the decrease of NO2(-). Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Evaluation of disinfection techniques for, and their effects on, rectal thermocouple catheters.

    PubMed

    MAHER, J T; ROGERS, M R; PETERSON, D W

    1961-07-01

    The antibacterial activities of an iodophor (Wescodyne G), a quaternary ammonium compound (Roccal), and an iodine tincture as agents for the cold disinfection of rectal catheters contaminated in vitro were determined. Following thorough cleaning with an alcoholic solution of soft soap, each of the three disinfectants tested showed satisfactory results (100% kill) in 5 min against the enteric test bacteria (Escherichia coli and Salmonella typhosa) as well as a test species of the genus Pseudomonas, among the bacteria most resistant to surface-active agents. An aqueous solution of Wescodyne G containing 75 ppm available iodine was used both as a wiping solution and for subsequent disinfection of rectal catheters contaminated in vivo. Total bacterial destruction was found to follow a 60-min soak preceded by the wiping procedure. Rectal catheters subjected to prolonged immersion in each of the test disinfectants were found to be essentially unaffected, retaining their initial calibrations within a permissible tolerance. Neither Roccal nor Wescodyne G solutions were found to measurably attack bare thermocouples. Alcoholic iodine 0.5% did, however, exert a deteriorating effect on bare thermocouples in a short time, as measured by change in resistance characteristics. The results of this study have led to the recommendation that Wescodyne G containing 75 ppm available iodine be used in standing operating procedures for the initial cleaning and subsequent disinfection of rectal thermocouple catheters.

  14. Evaluation of Disinfection Techniques for, and Their Effects on, Rectal Thermocouple Catheters1

    PubMed Central

    Maher, J. T.; Rogers, M. R.; Peterson, D. W.

    1961-01-01

    The antibacterial activities of an iodophor (Wescodyne G), a quaternary ammonium compound (Roccal), and an iodine tincture as agents for the cold disinfection of rectal catheters contaminated in vitro were determined. Following thorough cleaning with an alcoholic solution of soft soap, each of the three disinfectants tested showed satisfactory results (100% kill) in 5 min against the enteric test bacteria (Escherichia coli and Salmonella typhosa) as well as a test species of the genus Pseudomonas, among the bacteria most resistant to surface-active agents. An aqueous solution of Wescodyne G containing 75 ppm available iodine was used both as a wiping solution and for subsequent disinfection of rectal catheters contaminated in vivo. Total bacterial destruction was found to follow a 60-min soak preceded by the wiping procedure. Rectal catheters subjected to prolonged immersion in each of the test disinfectants were found to be essentially unaffected, retaining their initial calibrations within a permissible tolerance. Neither Roccal nor Wescodyne G solutions were found to measurably attack bare thermocouples. Alcoholic iodine 0.5% did, however, exert a deteriorating effect on bare thermocouples in a short time, as measured by change in resistance characteristics. The results of this study have led to the recommendation that Wescodyne G containing 75 ppm available iodine be used in standing operating procedures for the initial cleaning and subsequent disinfection of rectal thermocouple catheters. Images Fig. 1 PMID:13765378

  15. DISINFECTION BY-PRODUCT FORMATION BY ALTERNATIVE DISINFECTANTS AND REMOVAL BY GRANULAR ACTIVATED CARBON

    EPA Science Inventory

    The effects of the use of the alternative disinfectants on the formation of halogenated disinfection by–products (DBPs) including total organic halide, trihalomethanes, haloacetic acids, haloacetonitriles, haloketones, chloral hydrate, and chloropicrin, were examined along ...

  16. Multi-purpose droop controllers incorporating a passivity-based stabilizer for unified control of electronically interfaced distributed generators including primary source dynamics.

    PubMed

    Azimi, Seyed Mohammad; Afsharnia, Saeed

    2016-07-01

    This paper presents multi-purpose droop controllers for electronically-interfaced distributed generators (EI-DGs). These controllers allow the micro-grids to operate in grid-connected mode, islanded mode and mode transition transients with a unique control configuration. The active and reactive-power sharing among EI-DGs are satisfied by the proposed droop controllers in islanded mode. On the other hand, in the grid-connected mode, the droop controllers adjust the output active and reactive-powers of EI-DGs at the pre-programmed constant levels. The provision of sufficient damping capability and maintenance of the transient stability in all operational modes of EI-DGs are warranted by the suggested stabilizer. This stabilizer, which is designed using the passivity-based control (PBC) approach, is incorporated in the droop controllers to dampen power-angle, frequency and voltage deviations during large transients using solely local information. The primary source dynamics of EI-DGs are also considered. It is analytically proven that the presence of the primary source dynamics leads to attenuation of the damping capability of EI-DGs in transients. To compensate the adverse effect of the primary source dynamics during transients a novel compensator is inserted in the frequency-droop loop. Finally, time-domain simulations are performed on a multi-resources MG to verify the analytical results compared to those obtained, based on a recently-developed strategy. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  17. Integrated change detection and temporal trajectory analysis of coastal wetlands using high spatial resolution Korean Multi-Purpose Satellite series imagery

    NASA Astrophysics Data System (ADS)

    Nguyen, Hoang Hai; Tran, Hien; Sunwoo, Wooyeon; Yi, Jong-hyuk; Kim, Dongkyun; Choi, Minha

    2017-04-01

    A series of multispectral high-resolution Korean Multi-Purpose Satellite (KOMPSAT) images was used to detect the geographical changes in four different tidal flats between the Yellow Sea and the west coast of South Korea. The method of unsupervised classification was used to generate a series of land use/land cover (LULC) maps from satellite images, which were then used as input for temporal trajectory analysis to detect the temporal change of coastal wetlands and its association with natural and anthropogenic activities. The accurately classified LULC maps of KOMPSAT images, with overall accuracy ranging from 83.34% to 95.43%, indicate that these multispectral high-resolution satellite data are highly applicable to the generation of high-quality thematic maps for extracting wetlands. The result of the trajectory analysis showed that, while the variation of the tidal flats in the Gyeonggi and Jeollabuk provinces was well correlated with the regular tidal regimes, the reductive trajectory of the wetland areas belonging to the Saemangeum province was caused by a high degree of human-induced activities including large reclamation and urbanization. The conservation of the Jeungdo Wetland Protected Area in the Jeollanam province revealed that effective social and environmental policies could help in protecting coastal wetlands from degradation.

  18. The Source, Spatial Distribution and Risk Assessment of Heavy Metals in Soil from the Pearl River Delta Based on the National Multi-Purpose Regional Geochemical Survey

    PubMed Central

    Zhang, Lingyan; Guo, Shuhai; Wu, Bo

    2015-01-01

    The data on the heavy metal content at different soil depths derived from a multi-purpose regional geochemical survey in the Pearl River Delta (PRD) were analyzed using ArcGIS 10.0. By comparing their spatial distributions and areas, the sources of heavy metals (Cd, Hg, As and Pb) were quantitatively identified and explored. Netted measuring points at 25 ×25 km were set over the entire PRD according to the geochemical maps. Based on the calculation data obtained from different soil depths, the concentrations of As and Cd in a large area of the PRD exceeded the National Second-class Standard. The spatial disparity of the geometric centers in the surface soil and deep soil showed that As in the surface soil mainly came from parent materials, while Cd had high consistency in different soil profiles because of deposition in the soil forming process. The migration of Cd also resulted in a considerable ecological risk to the Beijiang and Xijiang River watershed. The potential ecological risk index followed the order Cd ≥ Hg > Pb > As. According to the sources, the distribution trends and the characteristics of heavy metals in the soil from the perspective of the whole area, the Cd pollution should be repaired, especially in the upper reaches of the Xijiang and Beijiang watershed to prevent risk explosion while the pollution of Hg and Pb should be controlled in areas with intense human activity, and supervision during production should be strengthened to maintain the ecological balance of As. PMID:26230506

  19. A novel multi-purpose enzymatic system and procedures for the rapid fluorescent determination of flavonoids in herbal pharmaceuticals and plant materials.

    PubMed

    Veselova, Irina; Malinina, Liubov; Barsukova, Marina; Tokareva, Anna; Buslova, Tatiana; Sokolova, Lidia; Pirogov, Andrey; Shekhovtsova, Tatiana

    2017-08-15

    The paper presents a novel multi-purpose enzymatic system and procedures for fluorescent determination of several flavonoids in herbal pharmaceuticals and plant materials after their enzyme-catalyzed oxidation by hydrogen peroxide and further derivatization with meso-1,2-diphenylethylenediamine. This system may be used for rapid (15-30min/20 samples) simultaneous screening of samples containing a certain flavonoid in a standard microplate, or as a HPLC detection system for analyzing plant extracts with uncertain composition. In the first case, this indicator system provides sensitive and reproducible microplate determination of quercetin, epicatechin, caffeic acid, and taxifolin in the ranges 0.1-5, 1-10, 0.1-10, 0.5-5μM, respectively. In the second case, quercetin, epicatechin, and caffeic acid can be determined in the ranges 0.05-0.75, 0.05-0.75, and 0.01-0.75µg/ml (0.16-2.5, 0.17-2.6, 0.06-4.2μM), respectively. We have demonstrated the application of the system for the analysis of 3 pharmaceuticals and 3 types of plants. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. A new analysis method using Bragg curve spectroscopy for a Multi-purpose Active-target Particle Telescope for radiation monitoring

    NASA Astrophysics Data System (ADS)

    Losekamm, M. J.; Milde, M.; Pöschl, T.; Greenwald, D.; Paul, S.

    2017-02-01

    Traditional radiation detectors can either measure the total radiation dose omnidirectionally (dosimeters), or determine the incoming particles characteristics within a narrow field of view (spectrometers). Instantaneous measurements of anisotropic fluxes thus require several detectors, resulting in bulky setups. The Multi-purpose Active-target Particle Telescope (MAPT), employing a new detection principle, is designed to measure particle fluxes omnidirectionally and be simultaneously a dosimeter and spectrometer. It consists of an active core of scintillating fibers whose light output is measured by silicon photomultipliers, and fits into a cube with an edge length of 10 cm. It identifies particles using extended Bragg curve spectroscopy, with sensitivity to charged particles with kinetic energies above 25 MeV. MAPT's unique layout results in a geometrical acceptance of approximately 800 cm2 sr and an angular resolution of less than 6°, which can be improved by track-fitting procedures. In a beam test of a simplified prototype, the energy resolution was found to be less than 1 MeV for protons with energies between 30 and 70 MeV. Possible applications of MAPT include the monitoring of radiation environments in spacecraft and beam monitoring in medical facilities.

  1. Nurses' perceptions of the impact of the aged care reform on services for residents in multi-purpose services and residential aged care facilities in rural Australia.

    PubMed

    Henderson, Julie; Willis, Eileen; Xiao, Lily; Toffoli, Luisa; Verrall, Claire

    2016-12-01

    To understand nurses' perceptions of the impact of the aged care reform on care and services for residents in multi-purpose services (MPS) and residential aged care facilities (RACF) in rural South Australia. An interpretative study using semi-structured interviews. Participants comprised registered and enrolled nurses working with aged care residents in rural South Australia. Eleven nurses were interviewed, of these seven worked in MPS and four in RACF. Data were analysed for similarities and differences in participants' experiences of care delivery between MPS and RACF. Common issues were identified relating to funding and resource shortfalls, staffing levels, skill mix and knowledge deficits. Funding and staffing shortfalls in MPS were related by participants to the lower priority given to aged care in allocating resources within MPS. Nurses in these services identified limited specialist knowledge of aged care and care deficits around basic nursing care. Nurses in RACF identified funding and staffing shortfalls arising from empty beds due to the introduction of the accommodation payment. Dependence upon care workers was associated with care deficits in complex care such as pain management, medication review and wound care. Further research is needed into the impact of recent reforms on the capacity to deliver quality aged care in rural regions. © 2016 AJA Inc.

  2. The Source, Spatial Distribution and Risk Assessment of Heavy Metals in Soil from the Pearl River Delta Based on the National Multi-Purpose Regional Geochemical Survey.

    PubMed

    Zhang, Lingyan; Guo, Shuhai; Wu, Bo

    2015-01-01

    The data on the heavy metal content at different soil depths derived from a multi-purpose regional geochemical survey in the Pearl River Delta (PRD) were analyzed using ArcGIS 10.0. By comparing their spatial distributions and areas, the sources of heavy metals (Cd, Hg, As and Pb) were quantitatively identified and explored. Netted measuring points at 25 ×25 km were set over the entire PRD according to the geochemical maps. Based on the calculation data obtained from different soil depths, the concentrations of As and Cd in a large area of the PRD exceeded the National Second-class Standard. The spatial disparity of the geometric centers in the surface soil and deep soil showed that As in the surface soil mainly came from parent materials, while Cd had high consistency in different soil profiles because of deposition in the soil forming process. The migration of Cd also resulted in a considerable ecological risk to the Beijiang and Xijiang River watershed. The potential ecological risk index followed the order Cd ≥ Hg > Pb > As. According to the sources, the distribution trends and the characteristics of heavy metals in the soil from the perspective of the whole area, the Cd pollution should be repaired, especially in the upper reaches of the Xijiang and Beijiang watershed to prevent risk explosion while the pollution of Hg and Pb should be controlled in areas with intense human activity, and supervision during production should be strengthened to maintain the ecological balance of As.

  3. Inhibition of Wnt signalling and breast tumour growth by the multi-purpose drug suramin through suppression of heterotrimeric G proteins and Wnt endocytosis.

    PubMed

    Koval, Alexey; Ahmed, Kamal; Katanaev, Vladimir L

    2016-02-15

    Overactivation of the Wnt signalling pathway underlies oncogenic transformation and proliferation in many cancers, including the triple-negative breast cancer (TNBC), the deadliest form of tumour in the breast, taking about a quarter of a million lives annually worldwide. No clinically approved targeted therapies attacking Wnt signalling currently exist. Repositioning of approved drugs is a promising approach in drug discovery. In the present study we show that a multi-purpose drug suramin inhibits Wnt signalling and proliferation of TNBC cells in vitro and in mouse models, inhibiting a component in the upper levels of the pathway. Through a set of investigations we identify heterotrimeric G proteins and regulation of Wnt endocytosis as the likely target of suramin in this pathway. G protein-dependent endocytosis of plasma membrane-located components of the Wnt pathway was previously shown to be important for amplification of the signal in this cascade. Our data identify endocytic regulation within Wnt signalling as a promising target for anti-Wnt and anti-cancer drug discovery. Suramin, as the first example of such drug or its analogues might pave the way for the appearance of first-in-class targeted therapies against TNBC and other Wnt-dependent cancers. © 2016 Authors; published by Portland Press Limited.

  4. Effects of species and season on chemical composition and ruminal crude protein and organic matter degradability of some multi-purpose tree species by West African dwarf rams.

    PubMed

    Arigbede, O M; Anele, U Y; Südekum, K-H; Hummel, J; Oni, A O; Olanite, J A; Isah, A O

    2012-04-01

    Seasonal chemical composition and ruminal organic matter (OM) and crude protein (CP) degradabilities were determined in four tropical multi-purpose tree species (MPTS) namely; Pterocarpus santalinoides, Grewia pubescens, Enterolobium cyclocarpum and Leucaena leucocephala. Three West African dwarf (WAD) rams fitted with permanent rumen cannula were used for the degradability trials. Foliage samples were collected four times to represent seasonal variations as follows: January--mid dry; April--late dry; July--mid rainy and October--late rainy seasons. Leaf samples were randomly collected from the trees for estimation of dry matter (DM) and chemical composition. Ruminal in sacco OM and CP degradabilities were estimated from residues in nylon bags. All samples had high CP (161-259 g/kg DM) and moderate fibre concentrations [neutral detergent fibre (without residual ash], 300-501 g/kg DM; acid detergent fibre (without residual ash), 225-409 g/kg DM and acid detergent lignin, 87-179 g/kg DM across seasons. Interaction effects of species and season on chemical composition were highly significant (p = 0.001) except for trypsin inhibitor (p = 0.614). The MPTS recorded more than 60% OM and CP degradability at 24 h, which implied that they were all highly degradable in the rumen. Their incorporation into ruminant feeding systems as dry season forage supplements is therefore recommended.

  5. [Irritating effect and dermal toxicity of virkon, a disinfectant widely used in Poland].

    PubMed

    Krysiak, B; Stetkiewicz, J; Kieć-Swierczyńska, M

    2000-01-01

    The aim of the study was to define the threshold irritating effect of Virkon, a disinfectant widely used in Poland, on the rabbit's skin and eye, and its dermal toxicity in single exposure. The studies were carried out according to the OECD guidelines, modified by Krysiak. A 10% aqueous solution of Virkon in the conditions of multiple open exposure was defined as the threshold concentration evoking small inflammatory reaction. After a single administration of Virkon in aqueous solutions into the rabbit's eye, the value of sensitising effect index was 1.5 for 1% solution of the disinfectant in question which indicates weak inflammatory reaction. The study of dermal toxicity in a single exposure revealed neither animal death nor morphological changes in internal organs which suggests non-cutaneous absorption of Virkon. The present study may provide the basis for assessing dermatological changes in people exposed to disinfectants.

  6. Influence of disinfection with peracetic acid and hypochlorite in dimensional alterations of casts obtained from addition silicone and polyether impressions.

    PubMed

    Queiroz, Daher Antonio; Peçanha, Marcelo Massaroni; Neves, Ana Christina Claro; Frizzera, Fausto; Tonetto, Mateus Rodrigues; Silva-Concílio, Laís Regiane

    2013-11-01

    Dental impressions disinfection is important to reduce the risk of cross contamination but this process may produce dimensional distortions. Peracetic acid is a disinfectant agent with several favorable characteristics yet underutilized in Dentistry. The aim of this paper is to compare the dimensional stability of casts obtained from addition silicone and polyether impressions that were immersed for 10 minutes in a solution of 0.2% peracetic acid or 1% sodium hypochlorite. Sixty samples in type IV gypsum were produced after a master cast that simulated a full crown preparation of a maxillary premolar. Samples were divided in 6 groups (n = 10) according to the impression material and disinfection agent: Group AC--addition silicone control (without disinfectant); Group APA--addition silicone + 0.2% peracetic acid; Group AH--addition silicone + 1% sodium hypochlorite; Group PC--polyether control (without disinfectant); Group PPA--polyether + 0.2% peracetic acid; Group PH--polyether + 1% sodium hypochlorite. Cast height, base and top diameter were measured and a mean value was obtained for each sample and group all data was statistically analyzed (ANOVA, p < 0.05). There was not a significant statistical difference between addition silicone and polyether impressions regardless of the disinfectant materials. It can be concluded that disinfection with the proposed agents did not produce significant alterations of the impressions and the peracetic acid could be considered a reliable material to disinfect dental molds.

  7. Status report on analytical methods to support the disinfectant/disinfection by-products regulation

    SciTech Connect

    Not Available

    1992-08-01

    The U.S. EPA is developng national regulations to control disinfectants and disinfection by-products in public drinking water supplies. Twelve disinfectants and disinfection by-products are identified for possible regulation under this rule. The document summarizes the analytical methods that EPA intends to propose as compliance monitoring methods. A discussion of surrogate measurements that are being considered for inclusion in the regulation is also provided.

  8. DRINKING WATER DISINFECTION BY-PRODUCTS: WHAT IS KNOWN

    EPA Science Inventory

    Chlorine, ozone, chlorine dioxide, and chloramine are currently the major disinfectants being used to disinfect drinking water. Although the alternative disinfectants (ozone, chlorine dioxide, and chloramine) are increasing in popularity in the United States, chlorine is still us...

  9. DRINKING WATER DISINFECTION BY-PRODUCTS: WHAT IS KNOWN

    EPA Science Inventory

    Chlorine, ozone, chlorine dioxide, and chloramine are currently the major disinfectants being used to disinfect drinking water. Although the alternative disinfectants (ozone, chlorine dioxide, and chloramine) are increasing in popularity in the United States, chlorine is still us...

  10. Disinfection associated spoilage of high water content ionic matrix hydrogels.

    PubMed

    Sack, R A; Harvey, H; Nunes, I

    1989-01-01

    Chemical analysis was carried out on clinically obtained hazy white hydrogel lenses that had been exposed to hydrogen peroxide disinfection. Analysis revealed that hazing was a surface phenomenon limited to high water content ionic matrix hydrogels (type IV), the type associated with the deposition of large amounts of lysozyme. We subjected unworn lenses to cycling studies involving doping in a variable artificial tear solution followed by exposure to disinfectant; this allowed us to duplicate the clinical situation and to derive a mechanism for this phenomenon. Hazing proved independent of the presence of hydrogen peroxide but dependent on the interaction of lens-bound lysozyme and stannate anion, the latter derived from sodium stannate present in the disinfectant as a stabilizing agent. Hazing is restricted to the type IV hydrogels because only these polymers have a sufficient number of anionic binding sites and are of sufficient porosity to allow the penetration and binding of a thick layer of lysozyme. Lysozyme is essential to hazing. No other tear protein is small enough to penetrate the hydrogel matrix or basic enough to have a marked affinity for the lens and to provide binding sites for stannate anion. These findings highlight the unique vulnerability of the type IV hydrogel to interaction with trace or transient ionic constituents in tears and lens care solutions.

  11. Micropollutants produced by disinfection of wastewater effluents

    SciTech Connect

    Jolley, R.L.; Cumming, R.B.; Lee, N.E.; Thompson, J.E.; Lewis, L.R.

    1981-01-01

    Recent research conducted with the objective of determining some of the chemical mutagenic characteristics of nonvolatile micropollutants in treated wastewater effluents is summarized. The effluents from nine wastewater plants were examined relative to the chemical effects of the disinfectants chlorine, ozone, and uv light on nonvolatile organic constituents and the formation of mutagenic constituents during disinfection. Results indicate that disinfection by chlorine or ozone can lead to an increase in the number of mutagenic materials in the effluents. (JGB)

  12. Ultra violet disinfection: A 3-year history

    SciTech Connect

    Tubesing, R.R.; Lindeke, D.R.

    1998-07-01

    The Stillwater Wastewater Treatment Facility is one of nine wastewater treatment facilities operated by the Metropolitan Council Environmental Services in the Minneapolis-St. Paul Metropolitan Area. The facility services the cities of Stillwater, Oak Park Heights, and Bayport. In 1993, an ultra violet disinfection facility began operation to provide the disinfection for the Facility. This presentation discusses the reasons for using ultra violet disinfection in lieu of chlorination/dechlorination facilities, the operating performance, and operating cost factors.

  13. Disinfecting Filters For Recirculated Air

    NASA Technical Reports Server (NTRS)

    Pilichi, Carmine A.

    1992-01-01

    Simple treatment disinfects air filters by killing bacteria, algae, fungi, mycobacteria, viruses, spores, and any other micro-organisms filters might harbor. Concept applied to reusable stainless-steel wire mesh filters and disposable air filters. Treatment used on filters in air-circulation systems in spacecraft, airplanes, other vehicles, and buildings to help prevent spread of colds, sore throats, and more-serious illnesses.

  14. Disinfecting Filters For Recirculated Air

    NASA Technical Reports Server (NTRS)

    Pilichi, Carmine A.

    1992-01-01

    Simple treatment disinfects air filters by killing bacteria, algae, fungi, mycobacteria, viruses, spores, and any other micro-organisms filters might harbor. Concept applied to reusable stainless-steel wire mesh filters and disposable air filters. Treatment used on filters in air-circulation systems in spacecraft, airplanes, other vehicles, and buildings to help prevent spread of colds, sore throats, and more-serious illnesses.

  15. Disinfection Addition and Disinfection Changes: What It Means to the LCR

    EPA Science Inventory

    This slide presentation’s general points are: Many protective pipe scales are vey dependent on ORP, and hence, state of disinfection. Adding disinfection to anoxic systems will likely cause big chemistry changes in DS and corrosion. Changing disinfectants could cause major l...

  16. 40 CFR 141.54 - Maximum residual disinfectant level goals for disinfectants.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum residual disinfectant level... (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Maximum Contaminant Level Goals and Maximum Residual Disinfectant Level Goals § 141.54 Maximum residual disinfectant level goals...

  17. Detection of regulated disinfection by-products in cheeses.

    PubMed

    Cardador, Maria Jose; Gallego, Mercedes; Cabezas, Lourdes; Fernández-Salguero, Jose

    2016-08-01

    Cheese can contain regulated disinfection by-products (DBPs), mainly through contact with brine solutions prepared in disinfected water or sanitisers used to clean all contact surfaces, such as processing equipment and tanks. This study has focused on the possible presence of up to 10 trihalomethanes (THMs) and 13 haloacetic acids (HAAs) in a wide range of European cheeses. The study shows that 2 THMs, (in particular trichloromethane) and 3 HAAs (in particular dichloroacetic acid) can be found at μg/kg levels in the 56 cheeses analysed. Of the two types of DBPs, HAAs were generally present at higher concentrations, due to their hydrophilic and non-volatile nature. Despite their different nature (THMs are lipophilic), both of them have an affinity for fatty cheeses, increasing their concentrations as the percentage of water decreased because the DBPs were concentrated in the aqueous phase of the cheeses.

  18. Disinfecting endoscopes: how not to transmit Mycobacterium tuberculosis by bronchoscopy.

    PubMed Central

    Leers, W D

    1980-01-01

    Mycobacterium tuberculosis was cultured from the bronchial washings of two patients who underwent bronchoscopy consecutively with the same bronchoscope. Active pulmonary tuberculosis was later confirmed in the first patient, whereas the second patient had clinical and serologic evidence of infection with respiratory syncytial virus. The bronchoscope had been cleaned with an iodophor disinfectant, which had not destroyed the tubercle bacilli. The agent recommended for chemical disinfection of fibreoptic bronchoscopes is 2% glutaraldehyde solution; the instrument should be immersed in it for 10 to 30 minutes. Five hours' exposure to ethylene oxide is recommended for sterilization of instruments. These procedures must be preceded by adequate mechanical cleaning. Then transmission of pathogenic organisms during endoscopy, which can result in nosocomial disease, misdiagnosis or inappropriate treatment, will be avoided. Images FIG. 1 FIG. 2 FIG. 3 PMID:6790150

  19. Decontamination formulations for disinfection and sterilization

    DOEpatents

    Tucker, Mark D.; Engler, Daniel E.

    2007-09-18

    Aqueous decontamination formulations that neutralize biological pathogens for disinfection and sterilization applications. Examples of suitable applications include disinfection of food processing equipment, disinfection of areas containing livestock, mold remediation, sterilization of medical instruments and direct disinfection of food surfaces, such as beef carcasses. The formulations include at least one reactive compound, bleaching activator, inorganic base, and water. The formulations can be packaged as a two-part kit system, and can have a pH value in the range of 7-8.

  20. Sporicidal activity of disinfectants as one possible cause for bacteria in patient-ready endoscopes.

    PubMed

    Miner, Norman; Harris, Valerie; Ebron, Towanda; Cao, Thuy-Dung

    2007-01-01

    Four endoscopes were cleaned by an experienced endoscopy technician using an enzyme detergent solution with brushing, rinsing with tap water, and then high-level disinfection in an automatic endoscope reprocessing machine using CIDEX orthophthalaldehyde solution (CIDEX OPA). After disinfection, the channels of these patient-ready endoscopes were flushed with sterile neutralizing medium, brushed with a sterile brush, and then flushed again with sterile medium. The effluent from each flush was collected in sterile bottles, immediately returned on ice to a laboratory, and tested for the presence of bacteria. An average of about 200 colony-forming units of bacteria were recovered from each endoscope. Upon staining and microscopic examination, 3 of these colonies were spore-forming bacteria, and 7 colonies were nonspore-forming bacteria. These results suggest that the endoscopes might have been contaminated with a biofilm. Bacterial biofilms have been speculated to commonly occur in endoscopes as a result of the many possible inadequacies of cleaning, disinfecting, rinsing, drying, storage, and other functions associated with the difficulties of reprocessing endoscopes. As one possible cause for a biofilm, three high-level disinfectants (CIDEX activated dialdehyde solution, CIDEX OPA, and Aldahol high-level disinfectant) were tested for their sporicidal activity against high-protein or low-protein cultures of spore-forming bacteria in suspension. The potential importance of killing spore-forming bacteria within a practical exposure time in order to prevent the formation of biofilms is discussed.

  1. Disinfection of dental unit water line using aloe vera: in vitro study.

    PubMed

    Pareek, Sonia; Nagaraj, Anup; Sharma, Prateek; Atri, Mansi; Walia, Satinder; Naidu, Shravani; Yousuf, Asif

    2013-01-01

    Context. Dental unit waterlines may be heavily contaminated with microorganisms and are a potential source of infection for both practicing staff and immunocompromised patients particularly. Contamination of dental unit water lines could be inhibited with the use of disinfectants. The present study investigates the effect of aloe-vera-based disinfectant in reducing the microbial growth in dental unit water lines (DUWLs). Aims. To compare the efficacy of aloe vera, hydrogen peroxide (H2O2), and 5% sodium hypochlorite (NaOCl) in controlling microbial contamination of DUWLs. Materials and Methods. After obtaining baseline water samples, the dental unit waterlines were treated with aloe vera, 10% hydrogen peroxide, and 5% sodium hypochlorite. Each of the three disinfectants was used in increasing concentrations and their inhibiting effect was compared. Water samples were analyzed for microbiological quality by the total viable count (TVC) method. Statistical Analysis Used. SPSS 16. Results. There was significant reduction in mean CFU/ml when treated with disinfectants each for a period of one week. Aloe-vera solution was found to be the most effective in reducing the microbial colonies. Conclusions. Improving the water quality from dental unit water lines is of considerable importance; chemical-based disinfectants can be replaced with herbal disinfectants for treating microbial contamination in dental unit waterlines.

  2. Wheelchair cleaning and disinfection in Canadian health care facilities: "That's wheelie gross!".

    PubMed

    Gardner, Paula; Muller, Matthew P; Prior, Betty; So, Ken; Tooze, Jane; Eum, Linda; Kachur, Oksana

    2014-11-01

    Wheelchairs are complex equipment that come in close contact with individuals at increased risk of transmitting and acquiring antibiotic-resistant organisms and health care-associated infection. The purpose of this study was to determine the status of wheelchair cleaning and disinfection in Canadian health care facilities. Acute care hospitals (ACHs), chronic care hospitals (CCHs), and long-term care facilities (LTCFs) were contacted and the individual responsible for oversight of wheelchair cleaning and disinfection was identified. A structured interview was conducted that focused on current practices and concerns, barriers to effective wheelchair cleaning and disinfection, and potential solutions. Interviews were completed at 48 of the 54 facilities contacted (89%), including 18 ACHs, 16 CCHs, and 14 LTCFs. Most (n = 24) facilities had 50-200 in-house wheelchairs. Respondents were very concerned about wheelchair cleaning as an infection control issue. Specific concerns included the lack of reliable systems for tracking and identifying dirty and clean wheelchairs (71%, 34/48), failure to clean and disinfect wheelchairs between patients (52%, 25/48), difficulty cleaning cushions (42%, 20/48), lack of guidelines (35%, 27/48), continued use of visibly soiled wheelchairs (29%, 14/48) and lack of resources (25%, 12/48). Our results suggest that wheelchair cleaning and disinfection is not optimally performed at many Canadian hospitals and LTCFs. Specific guidance on wheelchair cleaning and disinfection is necessary. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  3. Antibacterial activity of a plant extract and its potential for disinfecting gutta-percha cones.

    PubMed

    Brito-Júnior, Manoel; Nobre, Sérgio A M; Freitas, Juliana C P; Camilo, Carla C; Faria-e-Silva, André L

    2012-01-01

    This study evaluated the antibacterial activity of Rosmarinus officinalis extract and its potential for disinfecting guttapercha (GP) cones. In the first experiment, a hydro-alcoholic extract of Rosmarinus officinalis (leaves) in a dilution ratio of 10% m/v was tested against Enterococcus faecalis by using the disk diffusion method. Positive and negative controls were 70% cereal alcohol and antibiotics, respectively. The procedures were performed in triplicate, and the diameters of the zones of growth inhibition were measured with a caliper after 24 h at 37 degrees C. In the second experiment, the disinfection procedures were evaluated on GP cones artificially contaminated with Enterococcus faecalis. The R. officinalis extract was compared with 2% chlorhexidine digluconate and 2.5% sodium hypochlorite, using a direct exposure test (5 min treatment). Sterilized and non-disinfected cones were used as negative and positive controls, respectively. After 24 h of incubation, bacterial counts were taken. For both experiments, the data were statistically analyzed by Kruskall-Wallis and Tukey's tests (p < 0.05). The plant extract produced zones of inhibition comparable to those of tested antibiotics. Significant GP cone disinfection was verified with all disinfectant solutions, with no significant difference between them. R. officinalis extract showed bactericidal effect on Enterococcus faecalis and capacity to disinfect GP cones contamined with it.

  4. Disinfection of Dental Unit Water Line Using Aloe Vera: In Vitro Study

    PubMed Central

    Pareek, Sonia; Nagaraj, Anup; Sharma, Prateek; Walia, Satinder; Naidu, Shravani; Yousuf, Asif

    2013-01-01

    Context. Dental unit waterlines may be heavily contaminated with microorganisms and are a potential source of infection for both practicing staff and immunocompromised patients particularly. Contamination of dental unit water lines could be inhibited with the use of disinfectants. The present study investigates the effect of aloe-vera-based disinfectant in reducing the microbial growth in dental unit water lines (DUWLs). Aims. To compare the efficacy of aloe vera, hydrogen peroxide (H2O2), and 5% sodium hypochlorite (NaOCl) in controlling microbial contamination of DUWLs. Materials and Methods. After obtaining baseline water samples, the dental unit waterlines were treated with aloe vera, 10% hydrogen peroxide, and 5% sodium hypochlorite. Each of the three disinfectants was used in increasing concentrations and their inhibiting effect was compared. Water samples were analyzed for microbiological quality by the total viable count (TVC) method. Statistical Analysis Used. SPSS 16. Results. There was significant reduction in mean CFU/ml when treated with disinfectants each for a period of one week. Aloe-vera solution was found to be the most effective in reducing the microbial colonies. Conclusions. Improving the water quality from dental unit water lines is of considerable importance; chemical-based disinfectants can be replaced with herbal disinfectants for treating microbial contamination in dental unit waterlines. PMID:24089615

  5. [Evaluation of household chemical disinfectants for Vibrio cholerae EL TOR (non toxigenic strain)].

    PubMed

    Timenetsky, J; Yanaguita, R M; Silva, L A

    1992-10-01

    The methodology of microbiological evaluation of disinfectants in permanently being questioned because the laboratorial protocols do not correspond to the real conditions under which these products are used. In 1985 the Use-Dilution method of AOAC was adopted in Brazil for microbiological qualification of chemical disinfectants for commercial purposes. Domestic disinfectants are tested in this way against Salmonella choleraesuis and Staphylococcus aureus ATCC strains, was chosen for this evaluation Vibrio cholerae in view of its current importance in Brazil, in terms of Public Health associated with the study of the disinfectant's antimicrobial activities. Nineteen disinfectant products for domestic use for available to the public were evaluated microbiologically by means of simplified Use-Dilution test with 10 carriers. The active compounds of the products included formaldehyde, phenols, cresols, quaternary ammonium compounds, chlorine and ethanol. Seven were mixtures of these. According to the recommendations for their use, sixteen products should be used undiluted. Under these conditions, 9 disinfectants were vibriocides and 7 did not demonstrate this antibacterial activity. Four products in dilutions not clearly specified were also ineffective. The vibriocide products which must used without dilution were tested again, diluted at 1:2. These solutions did not inactivate V. cholerae showing that, microbiologically, their active compounds are used in limited concentrations. Commercial alcohol (95.5 degrees GL) at 1:3, chlorine 2.8% Agua sanitária at 1:200 and Lysoform at 1:20 came up to the standards required by the test.

  6. Chlorate as an inorganic disinfection by product in swimming pools.

    PubMed

    Erdinger, L; Kirsch, F; Sonntag, H G

    1999-06-01

    Chlorate and chlorite concentrations were determined in water samples taken from 33 swimming pools. In the pools under investigation, disinfection of the water is carried out either by gaseous chlorine (n = 14) or hypochlorite solution in conjunction with flocculation and sand filtration. A number of the pools also use ozone treatment to augment the disinfection process. Chlorite was not detectable in any of the samples (detection limit 1 mg/l). High concentrations of chlorate were detected in samples from a number of the pools; in one case as high as 40 mg/l. Higher chlorate concentrations were found to be associated with those pools using hypochlorite solution as a disinfecting agent. In contrast, relatively low chlorate concentrations were found in pools treated with gaseous chlorine. In order to elucidate any relationship between the chlorate content of pool water and that of the respective hypochlorite stock solution, chlorate and bromate concentrations were determined in the hypochlorite stock solutions of nine pools. Bromate concentration in the stock solutions were not found to exceed 1.2 g/l, chlorate was measured in concentrations of up to 44.5 g/l. The additional use of ozone as part of the water purification process appears to have no significant influence on chlorate concentration. Chlorate has no bactericidal properties and does not interfere with the measurement of certain parameters relevant to hygiene in swimming pools such as free and combined chlorine, pH or redox potential. At present, the effects of high chlorate concentrations in swimming pool water are unclear. Our initial investigations indicate that chlorate has no cytotoxic (Neutral-Red assay) or irritating properties (HET-CAM assay). However, both chlorate and chlorite are known to interfere with the haematopoetic system. In Germany, the MCL for chlorite in drinking water is 0.2 mg/l. It is therefore strongly recommended that measures should be taken to reduce chlorate concentrations in

  7. Development of a new single-bottle multi-purpose primer for bonding to dental porcelain, alumina, zirconia, and dental gold alloy.

    PubMed

    Ikemura, Kunio; Tanaka, Hisaki; Fujii, Toshihide; Deguchi, Mikito; Endo, Takeshi; Kadoma, Yoshinori

    2011-01-01

    This study investigated the bonding efficacy of a combined primer application which comprised a silane coupling agent, an acidic adhesive monomer, and a dithiooctanoate monomer, as well as the influence of shelf life on bonding. Five experimental primers (coded as Si-P-SS-1 to Si-P-SS-4, and Si-SS as the control) were prepared using 20.0-40.0 wt% 3-methacryloyloxypropyltriethoxysilane (3-MPTES), 0-7.44 wt% 6-methacryloyloxyhexyl phosphonoacetate (6-MHPA), and 0.50 wt% 10-methacryloyloxydecyl 6,8-dithiooctanoate (10-MDDT). After 24-hour storage at 23°C (Initial) and 2-month storage at 50°C (Aged), tensile bond strengths (TBSs) of a resin cement (ResiCem, Shofu Inc., Kyoto, Japan) to primer-treated porcelain, alumina, zirconia, and Au alloy were measured. With the Initial and Aged primers of Si-P-SS-1 to Si-P-SS-3, there were no statistically significant differences in the mean TBSs (MPa) [porcelain: 21.7-29.2; alumina: 21.4-25.3; zirconia: 20.3-24.5; and Au alloy: 23.4-27.6] among these three primers (p>0.05), but they were significantly higher than that of the control primer (p<0.05). The experimental primers Si-P-SS-1 to Si-P-SS-3 demonstrated good potential as multi-purpose primers: they had good shelf lives as single-bottle primer systems and were thus able to exhibit good bond strength to all the adherends tested after 2-month storage under accelerated aging conditions.

  8. Liquid Methane Conditioning Capabilities Developed at the NASA Glenn Research Center's Small Multi- Purpose Research Facility (SMiRF) for Accelerated Lunar Surface Storage Thermal Testing

    NASA Technical Reports Server (NTRS)

    Bamberger, Helmut H.; Robinson, R. Craig; Jurns, John M.; Grasl, Steven J.

    2011-01-01

    Glenn Research Center s Creek Road Cryogenic Complex, Small Multi-Purpose Research Facility (SMiRF) recently completed validation / checkout testing of a new liquid methane delivery system and liquid methane (LCH4) conditioning system. Facility checkout validation was conducted in preparation for a series of passive thermal control technology tests planned at SMiRF in FY10 using a flight-like propellant tank at simulated thermal environments from 140 to 350K. These tests will validate models and provide high quality data to support consideration of LCH4/LO2 propellant combination option for a lunar or planetary ascent stage.An infrastructure has been put in place which will support testing of large amounts of liquid methane at SMiRF. Extensive modifications were made to the test facility s existing liquid hydrogen system for compatibility with liquid methane. Also, a new liquid methane fluid conditioning system will enable liquid methane to be quickly densified (sub-cooled below normal boiling point) and to be quickly reheated to saturation conditions between 92 and 140 K. Fluid temperatures can be quickly adjusted to compress the overall test duration. A detailed trade study was conducted to determine an appropriate technique to liquid conditioning with regard to the SMiRF facility s existing infrastructure. In addition, a completely new roadable dewar has been procured for transportation and temporary storage of liquid methane. A new spherical, flight-representative tank has also been fabricated for integration into the vacuum chamber at SMiRF. The addition of this system to SMiRF marks the first time a large-scale liquid methane propellant test capability has been realized at Glenn.This work supports the Cryogenic Fluid Management Project being conducted under the auspices of the Exploration Technology Development Program, providing focused cryogenic fluid management technology efforts to support NASA s future robotic or human exploration missions.

  9. Microbial contamination of disinfectants used for intermittent self-catheterization.

    PubMed

    Hakuno, Harumasa; Yamamoto, Mitutaka; Oie, Shigeharu; Kamiya, Akira

    2010-07-01

    We investigated the microbial contamination of 0.02% benzalkonium chloride solution used in catheter kits for intermittent self-catheterization. Of 20 samples examined, 12 (60.0%) were contaminated with 8.8 x 10(2)-3.1 x 10(6) colony-forming units (cfu)/mL. The contaminants were Pseudomonas fluorescens, Burkholderia cepacia, and Aeromonas spp. These results showed that 0.02% benzalkonium chloride solution used for the lubrication/disinfection of catheters for self-catheterization is susceptible to contamination. Therefore, the lubricant/disinfectant for catheters for self-catheterization was changed from 0.02% benzalkonium chloride solution to 84-87% glycerin containing 0.02% benzalkonium chloride, and microbial contamination of the latter in catheter kits for self-catheterization was reinvestigated. Of 42 samples, 5 (11.9%) were contaminated with 20-2.0 x 10(4) cfu/mL. However, the rate of contamination of 84-87% glycerin containing 0.02% benzalkonium chloride was significantly lower than that of 0.02% benzalkonium chloride solution (P<0.0001). The contaminant of 84-87% glycerin containing 0.02% benzalkonium chloride was Bacillus spp. in all contaminated samples. In this survey, neither contaminants of 0.02% benzalkonium chloride solution nor the contaminant of 84-87% glycerin containing 0.02% benzalkonium chloride were the causative microbial species of urinary tract infection.

  10. [Electrochemical disinfection using the gas diffusion electrode system].

    PubMed

    Xu, Wen-Ying; Li, Ping; Dong, Bin

    2010-01-01

    Study on the electrochemical disinfection with the H2O2 produced at the gas diffusion electrode (GDE) prepared from active carbon/ poly-tetrafluoroethylene (PTFE) was performed in the non-membrane cell. The effects of PTFE mass fraction W(PTFE) and content of the pore-forming agent in GDE m(NH4CO3), operating conditions such as pH value and oxygen flow rate Q(o2)) on disinfection were investigated, respectively. The experimental results showed that H2 O2 reached peak production at W(PTFE) of 0.5 in GDE. Addition of the pore-forming agent in the appropriate amount improved the disinfection, and this phenomenon was more obvious at neutral pH than at acidic pH. BET specific area analysis indicated that the average pore size in the membrane electrode first decreased significantly with the increasing amount of pore-forming agent, and then increased moderately. This helped the mass transfer of oxygen at the GDE. Adsorption made little or no progress to kill the bacteria during the electrolysis. Drop of pH value resulted in a rapid rise of the germicidal efficacy. This system had a broad pH coverage: when total bacterial count in raw water was 10(6) CFU x mL(-1), pH 3-10,the germicidal efficacy was greater than 80% after 30 min electrolysis using the GDE with W(Pt) of 3 per thousand as cathode. Increase of the oxygen flow rate Q(o2) within limits had little influence on the production of H2 O2 and the succeeding disinfection. On one hand, resistance of the solution and energy consumption on the disinfection increased at high oxygen flow rate, which gave rise to an increase in the operating cost of disinfection with the GDE system; on the other hand, treatment time could be reduced reasonably at high oxygen flow rate, which leads to reduction of equipment investment. Killing mechanism study showed that the direct oxidation and formation of the free radicals at the anode played a greater role in the beginning, and then the oxidative indirect effect of the generated H2 O2 at

  11. An EPR study on wastewater disinfection by peracetic acid, hydrogen peroxide and UV irradiation.

    PubMed

    Bianchini, Roberto; Calucci, Lucia; Caretti, Cecilia; Lubello, Claudio; Pinzino, Calogero; Piscicelli, Michela

    2002-09-01

    EPR spectroscopy was applied to obtain qualitative and quantitative information on the radicals produced in disinfection processes of wastewater for agricultural reuse. The DEPMPO spin trap was employed to detect hydroxyl and carbon-centered short living radicals in two different peracetic acid solutions and a hydrogen peroxide solution used for water disinfection either in the absence or in the presence of UV-C irradiation. Moreover, three different kinds of water (wastewater, demineralized water, distilled water) were analysed in order to assess the contribution of Fenton reactions to the radical production. The spectroscopic results were discussed in relation to the efficiency of the different oxidizing agents and UV irradiation in wastewater disinfection evaluated as Escherichia Coli, Faecal and Total Coliforms inactivation.

  12. Kinetics and influence of water composition on photocatalytic disinfection and photocatalytic oxidation of pollutants.

    PubMed

    Marugán, Javier; van Grieken, Rafael; Pablos, Cristina

    2010-12-01

    This work is focused on the comparison between the photocatalytic inactivation of Escherichia coli and the photocatalytic oxidation of methylene blue, regarding the reaction kinetics and the influence of water composition. Disinfection profiles show an initial delay, in contrast with the exponential decay shown by the decolorization of methylene blue solutions. A serial-event mechanism is proposed for both disinfection and mineralization processes, the number of intermediate species being the main difference between them. Concerning the influence of water composition, inactivation of bacteria is more sensitive to the presence of inorganic ions and/or organic matter in the solution. In some cases opposite behaviours are observed, such as in the presence of chloride ions, which enhance the disinfection rate but decrease degradation activity for methylene blue. Consequently, the results obtained in the evaluation of photocatalytic processes for the degradation of chemical pollutants cannot be always extrapolated to the inactivation of microorganisms.

  13. 40 CFR 141.72 - Disinfection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PRIMARY DRINKING WATER REGULATIONS Filtration and Disinfection § 141.72 Disinfection. A public water system that uses a surface water source and does not provide filtration treatment must provide the... determines that filtration is required in writing pursuant to § 1412 (b)(7)(C)(iii). A public water...

  14. MUTAGENICITY OF DRINKING WATER FOLLOWING DISINFECTION

    EPA Science Inventory

    Many drinking water utilities in the USA are considering alternatives to chlorine for disinfection in order to comply with federal regulations regarding disinfection by-products. An evaluation is thus needed of the potential risks associated with the use of alternative disinfecta...

  15. ULTRAVIOLET DISINFECTION STUDIES WITH CCL LISTED MICROORGANISMS

    EPA Science Inventory

    Resistance to ultraviolet (UV) disinfection is an essential aspect regarding all microbial groups listed on the CCL. The U.S. drinking water industry is interested in including UV light treatment as an amendment to conventional treatment for disinfecting water supplies. UV disi...

  16. Ultraviolet (UV) Disinfection for Drinking Water Systems

    EPA Science Inventory

    UV disinfection is an effective process for inactivating many microbial pathogens in water with potential to serve as stand-alone treatment or in combination with other disinfectants. USEPA provided guidance on the validation of UV reactors nearly a decade ago. Since then, lesson...

  17. 40 CFR 141.72 - Disinfection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for Giardia lamblia cysts and viruses. If a system uses a disinfectant other than chlorine, the system...) The residual disinfectant concentration in the distribution system, measured as total chlorine, combined chlorine, or chlorine dioxide, as specified in § 141.74 (a)(2) and (b)(6), cannot be...

  18. 40 CFR 141.72 - Disinfection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for Giardia lamblia cysts and viruses. If a system uses a disinfectant other than chlorine, the system...) The residual disinfectant concentration in the distribution system, measured as total chlorine, combined chlorine, or chlorine dioxide, as specified in § 141.74 (a)(2) and (b)(6), cannot be...

  19. Silver disinfection in water distribution systems

    NASA Astrophysics Data System (ADS)

    Silvestry Rodriguez, Nadia

    Silver was evaluated as disinfectant to maintain water quality in water distribution system. It was used to inhibit growth of two opportunistic bacteria in planktonik form and in biofilm formation in Robbins devices with stainless steel and PVC surfaces. The results of this work show that silver is a potential secondary disinfectant to be used in water distribution systems.

  20. How to improve instrument disinfection by ultrasound.

    PubMed

    Jatzwauk, L; Schöne, H; Pietsch, H

    2001-08-01

    Ultrasound technologies have a wide range of hospital and dental applications which include cleaning and disinfection of surgical and dental instruments. We measured the germicidal efficacy of sonication, with or without chemical disinfectants, in an ultrasonic bath delivering a frequency of 35 kHz and an intensity of 0.66 W/cm2. Cultures of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans were exposed to ultrasound and to an amine-based disinfectant in non-bactericidal concentrations. Ultrasonication for 60 min alone did not cause a significant killing of the bacteria and yeast. However, we were able to show that sonication can act as a powerful synergistic agent to increase the cidal efficacy of the disinfectant against S. aureus and P. aeruginosa. C. albicans was more resistant to the combination of ultrasound and chemical disinfection. The key role in the action of ultrasound in cleaning of instruments and perhaps in enhanced disinfection is played by cavitation phenomena. The distribution of cavitations in an ultrasonic bath is not homogenous. We found a similar synergistic effect of ultrasound and disinfectant in positions with low cavitation. The synergistic effect was not reduced inside rubber tubes. Before ultrasound can be accepted as an integral part of the cleaning and disinfection process of medical instruments, the influence of intensity and frequency of sonication and the effects of cavitation must be clarified.

  1. Ultraviolet (UV) Disinfection for Drinking Water Systems

    EPA Science Inventory

    UV disinfection is an effective process for inactivating many microbial pathogens in water with potential to serve as stand-alone treatment or in combination with other disinfectants. USEPA provided guidance on the validation of UV reactors nearly a decade ago. Since then, lesson...

  2. ULTRAVIOLET DISINFECTION STUDIES WITH CCL LISTED MICROORGANISMS

    EPA Science Inventory

    Resistance to ultraviolet (UV) disinfection is an essential aspect regarding all microbial groups listed on the CCL. The U.S. drinking water industry is interested in including UV light treatment as an amendment to conventional treatment for disinfecting water supplies. UV disi...

  3. The effect of disinfectants on dimensional stability of addition and condensation silicone impressions.

    PubMed

    Sinobad, Tamara; Obradović-Djuricić, Kosovka; Nikolić, Zoran; Dodić, Slobodan; Lazić, Vojkan; Sinobad, Vladimir; Jesenko-Rokvić, Aleksandra

    2014-03-01

    Dimensional stability and accuracy of an impression after chemical disinfection by immersion in disinfectants are crucial for the accuracy of final prosthetic restorations. The aim of this study was to assess the deformation of addition and condensation silicone impressions after disinfection in antimicrobial solutions. A total of 120 impressions were made on the model of the upper arch representing three full metal-ceramic crown preparations. Four impression materials were used: two condensation silicones (Oranwash L - Zhermack and Xantopren L Blue - Heraeus Kulzer) and two addition silicones (Elite H-D + regular body - Zhermack and Flexitime correct flow - Heraeus Kulzer). After removal from the model the impressions were immediatel immersed in appropriate disinfectant (glutaraldehyde, benzalkonium chloride - Sterigum and 5.25% NaOC1) for a period of 10 min. The control group consisted of samples that were not treated with disinfectant solution. Consecutive measurements of identical impressions were realized with a Canon G9 (12 megapixels, 2 fps, 6x/24x), and automated with a computer Asus Lamborghini VX-2R Intel C2D 2.4 GHz, by using Remote Capture software package, so that time-depending series of images of the same impression were obtained. The dimensional changes of all the samples were significant both as a function of time and the applied disinfectant. The results show significant differences of the obtained dimensional changes between the group of condensation silicones and the group of addition silicones for the same time, and the same applied disinfectant (p = 0.026, F = 3.95). The greatest dimensional changes of addition and condensation silicone impressions appear in the first hour after their separation from the model.

  4. Sepsis, parenteral vaccination and skin disinfection.

    PubMed

    Cook, Ian F

    2016-10-02

    ASBSTRACT Disinfection should be required for all skin penetrative procedures including parenteral administration of vaccines. This review analyses medically attended infectious events following parenteral vaccination in terms of their microbiological aetiology and pathogenesis. Like 'clean' surgical site infections, the major pathogens responsible for these events were Staphylococcal species, implicating endogenous con-tamination as a significant source of infection. As 70% isopropyl alcohol swabbing has been shown to effectively disinfect the skin, it would be medico-legally difficult to defend a case of sepsis with the omission of skin disinfection unless the very low risk of this event was adequately explained to the patient and documented prior to vaccination. There was a significant cost-benefit for skin disinfection and cellulitis. Skin disinfection in the context of parenteral vaccination represents a new paradigm of medical practice; the use of a low cost intervention to prevent an event of very low prevalence but of significant cost.

  5. Susceptibility of Vaccinia Virus to Chemical Disinfectants

    PubMed Central

    de Oliveira, Tércia Moreira Ludolfo; Rehfeld, Izabelle Silva; Coelho Guedes, Maria Isabel Maldonado; Ferreira, Jaqueline Maria Siqueira; Kroon, Erna Geessien; Lobato, Zélia Inês Portela

    2011-01-01

    Vaccinia virus (VACV) is the cause of bovine vaccinia (BV), an emerging zoonotic disease that affects dairy cows and milkers. Some chemical disinfectants have been used on farms affected by BV to disinfect cow teats and milkers' hands. To date, there is no information about the efficacy of disinfectants against VACV. Therefore, this study aimed to assess the virucidal activity of some active disinfectants commonly used in the field. Sodium hypochlorite, quaternary ammonium combined with chlorhexidine, and quaternary ammonium combined with glutaraldehyde were effective in inactivating the virus at all concentrations tested. Iodine and quaternary ammonium as the only active component were partially effective. The presence of bovine feces as organic matter and light decreased the effectiveness of sodium hypochlorite. These results show that an appropriated disinfection and asepsis of teats and hands may be helpful in the control and prevention of BV and other infections with VACV. PMID:21734141

  6. Hazards with disinfecting agents in renal units!

    PubMed

    Stragier, A

    1992-02-01

    As already described in the April 1991 issue of EDTNA/ERCA Journal (Volume XVII, No. 2), the specific characteristics of various disinfecting agents delineate their respective application areas. Obviously, in a renal unit one needs a large range of disinfecting agents as they are being used for cleaning and disinfection of: water treatment devices; water tanks and distribution systems; single patient units; patient vascular access sites; dialysis connection procedure; dialyser reuse; instruments; floors, etc.... We have been taught never to mix different disinfecting agents as this might reduce their efficiency. However, it had never been hitherto reported that this might be dangerous or even cause an explosion! In this paper, we describe in detail how we were confronted with such an explosion. We further report that similar hazards occurred in other units and present an overview of possible hazards with the most common disinfecting agents. Finally, we emphasize some preventive guidelines to be put forth in renal units.

  7. Sepsis, parenteral vaccination and skin disinfection

    PubMed Central

    Cook, Ian F.

    2016-01-01

    ASBSTRACT Disinfection should be required for all skin penetrative procedures including parenteral administration of vaccines. This review analyses medically attended infectious events following parenteral vaccination in terms of their microbiological aetiology and pathogenesis. Like ‘clean’ surgical site infections, the major pathogens responsible for these events were Staphylococcal species, implicating endogenous con-tamination as a significant source of infection. As 70% isopropyl alcohol swabbing has been shown to effectively disinfect the skin, it would be medico-legally difficult to defend a case of sepsis with the omission of skin disinfection unless the very low risk of this event was adequately explained to the patient and documented prior to vaccination. There was a significant cost-benefit for skin disinfection and cellulitis. Skin disinfection in the context of parenteral vaccination represents a new paradigm of medical practice; the use of a low cost intervention to prevent an event of very low prevalence but of significant cost. PMID:27295449

  8. Variability of Burkholderia pseudomallei strain sensitivities to chlorine disinfection.

    PubMed

    O'Connell, Heather A; Rose, Laura J; Shams, Alicia; Bradley, Meranda; Arduino, Matthew J; Rice, Eugene W

    2009-08-01

    Burkholderia pseudomallei is a select agent and the causative agent of melioidosis. Variations in previously reported chlorine and monochloramine concentration time (Ct) values for disinfection of this organism make decisions regarding the appropriate levels of chlorine in water treatment systems difficult. This study identified the variation in Ct values for 2-, 3-, and 4-log(10) reductions of eight environmental and clinical isolates of B. pseudomallei in phosphate-buffered water. The greatest calculated Ct values for a 4-log(10) inactivation were 7.8 mg.min/liter for free available chlorine (FAC) at pH 8 and 5 degrees C and 550 mg.min/liter for monochloramine at pH 8 and 5 degrees C. Ionic strength of test solutions, culture hold times in water, and cell washing were ruled out as sources of the differences in prior observations. Tolerance to FAC was correlated with the relative amount of extracellular material produced by each isolate. Solid-phase cytometry analysis using an esterase-cleaved fluorochrome assay detected a 2-log(10)-higher level of organisms based upon metabolic activity than did culture, which in some cases increased Ct values by fivefold. Despite strain-to-strain variations in Ct values of 17-fold for FAC and 2.5-fold for monochloramine, standard FAC disinfection practices utilized in the United States should disinfect planktonic populations of these B. pseudomallei strains by 4 orders of magnitude in less than 10 min at the tested temperatures and pH levels.

  9. Effect of Presurgical Iodine-Based Disinfection on Bacterial Colonization of the Equine Peripodal Region.

    PubMed

    Johnson, Jessica; Messier, Serge; Meulyzer, Michael; Vinardell, Tatiana; Marcoux, Marcel; David, Florent

    2015-08-01

    To compare bacterial colonization after diluted iodine tincture or povidone iodine solution for presurgical disinfection of the equine peripodal region. Complete block design. Five horses. Disinfection protocols using iodine tincture or povidone iodine solutions were tested on 5 pairs (n = 10) equine front feet. Iodine tincture was applied to the left feet and povidone iodine to the right feet. Fixed surfaces of the sole, frog, hoof wall, and peripodal skin were swabbed pre-preparation (T0), after a standard pre-disinfection step (T1), after short disinfection with a 4-minute application of 0.5% iodine tincture or povidone iodine (T2), and after long disinfection with 12-hour soaking in 0.25% iodine tincture or povidone iodine (T3). Quantitative bacteriology was performed on each swab. The frog and sole were the most contaminated sites compared to hoof wall and skin at T0. Bacterial counts were significantly decreased at T2 for both solutions. Bacterial counts did not change significantly with iodine tincture at T3 but increased with povidone iodine compared to T2. Skin abrasions were detected on almost all feet but were subjectively more severe on iodine tincture-treated feet. Soaking for 12 hours with either iodine tincture or povidone iodine is not recommended as these solutions damaged the skin and bacterial recolonization was noted with povidone iodine. Four-minute disinfection using either iodine tincture or povidone iodine (0.5% available iodine) is appropriate for presurgical preparation of the equine peripodal region. © Copyright 2015 by The American College of Veterinary Surgeons.

  10. Root canal disinfection of immature dog teeth with apical periodontitis: Comparison of three different protocols

    PubMed Central

    Rodríguez-Benítez, Soledad; Stambolsky Guelfand, Carlos; Martín-Jiménez, Milagros

    2014-01-01

    Objectives: The present in vivo study was designed to assess the efficacy of 3 root canal disinfection protocols in immature dog teeth with apical periodontitis (AP). Material and Methods: Forty immature premolars with pulp necrosis and AP of five Beagle dogs were used. Three experimental disinfection protocols were established. After irrigation with 40 ml 5.25% sodium hypochlorite using the Endovac system, in Group 1 canals were flushed with QMix solution; in Group 2, canals were flushed with QMix solution and 2% chlorhexidine gel dressing was placed for two weeks; and in Group 3, triantibiotic paste dressing was placed for two weeks. Canals were sampled after periapical lesions were radiographically visible (S1), after the first disinfection session (S2) and, in groups 2 and 3, after dressing (S3). Results: After the first session of the disinfection protocol (S2), there was significant (p < 0.05) bacterial reduction in the three experimental groups. Microorganisms were absent in 100% of S2 samples in groups 1 and 2, and in 75% of group 3 (p > 0.05). After dressing, 87.5% of the S3 samples showed increased bacterial count: in group 2, CFU counts (median = 891) were significantly higher than in group 3 (median = 18) (p = 0.03). Conclusions: In immature dog teeth with AP, root canal irrigation using QMix solution, with or without chlorhexidine gel dressing, or a triantibiotic paste dressing, provides the same level of disinfection than irrigation with 5.25% sodium hypochlorite alone in only one session. Key words:Apical periodontitis, chlorhexidine, Endovac, immature teeth, QMix solution, root canal disinfection, triantibiotic paste. PMID:25593656

  11. Comparison of three different sterilization and disinfection methods on orthodontic markers.

    PubMed

    Omidkhoda, Maryam; Rashed, Roozbeh; Bagheri, Zahra; Ghazvini, Kiarash; Shafaee, Hooman

    2016-01-01

    Marking pencils which are frequently used in orthodontics may cause microbial contamination. The purpose of this study was to evaluate and compare the effectiveness of three disinfection and sterilization methods (autoclave, glutaraldehyde solution, and Deconex spray) on orthodontic markers. One hundred and twenty orthodontic markers were divided into four groups each 30 pencils: One control group and three groups for three different disinfection/sterilization methods. To evaluate the effectiveness of these methods, pencils were initially contaminated by common pathogen by immersing the pencils in a suspension containing 1.5 × 10(8) CFU/ml organisms. Then, the pencils were subjected to corresponding disinfection/sterilization methods, and the number of remaining microorganisms was calculated and compared with control group. In the control group, the mean number of Escherichia coli was significantly higher than the other two microorganisms (P = 0.01, P = 0.031). However, the mean numbers of Staphylococcus aureus and Candida albicans were not significantly different (P = 0.1). After sterilization with autoclave and glutaraldehyde, no microbial growth was observed, whereas after disinfection with Deconx spray some colonies of microorganisms still could be observed. Autoclaving and glutaraldehyde solution are the best methods for disinfecting orthodontic markers.

  12. Comparison of three different sterilization and disinfection methods on orthodontic markers

    PubMed Central

    Omidkhoda, Maryam; Rashed, Roozbeh; Bagheri, Zahra; Ghazvini, Kiarash; Shafaee, Hooman

    2016-01-01

    Background: Marking pencils which are frequently used in orthodontics may cause microbial contamination. The purpose of this study was to evaluate and compare the effectiveness of three disinfection and sterilization methods (autoclave, glutaraldehyde solution, and Deconex spray) on orthodontic markers. Materials and Methods: One hundred and twenty orthodontic markers were divided into four groups each 30 pencils: One control group and three groups for three different disinfection/sterilization methods. To evaluate the effectiveness of these methods, pencils were initially contaminated by common pathogen by immersing the pencils in a suspension containing 1.5 × 108 CFU/ml organisms. Then, the pencils were subjected to corresponding disinfection/sterilization methods, and the number of remaining microorganisms was calculated and compared with control group. Results: In the control group, the mean number of Escherichia coli was significantly higher than the other two microorganisms (P = 0.01, P = 0.031). However, the mean numbers of Staphylococcus aureus and Candida albicans were not significantly different (P = 0.1). After sterilization with autoclave and glutaraldehyde, no microbial growth was observed, whereas after disinfection with Deconx spray some colonies of microorganisms still could be observed. Conclusion: Autoclaving and glutaraldehyde solution are the best methods for disinfecting orthodontic markers. PMID:26998472

  13. 7 CFR 301.89-12 - Cleaning, disinfection, and disposal.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Cleaning, disinfection, and disposal. 301.89-12... Cleaning, disinfection, and disposal. (a) Mechanized harvesting equipment that has been used to harvest... and, if disinfection is determined to be necessary by an inspector, disinfected in accordance with...

  14. 40 CFR 141.172 - Disinfection profiling and benchmarking.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... appropriate, through the entire treatment plant. This system must begin this monitoring not later than April 1...) The temperature of the disinfected water must be measured once per day at each residual disinfectant... disinfected water must be measured once per day at each chlorine residual disinfectant concentration...

  15. 40 CFR 141.172 - Disinfection profiling and benchmarking.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... appropriate, through the entire treatment plant. This system must begin this monitoring not later than April 1...) The temperature of the disinfected water must be measured once per day at each residual disinfectant... disinfected water must be measured once per day at each chlorine residual disinfectant concentration...

  16. 40 CFR 141.172 - Disinfection profiling and benchmarking.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... appropriate, through the entire treatment plant. This system must begin this monitoring not later than April 1...) The temperature of the disinfected water must be measured once per day at each residual disinfectant... disinfected water must be measured once per day at each chlorine residual disinfectant concentration...

  17. 40 CFR 141.172 - Disinfection profiling and benchmarking.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... appropriate, through the entire treatment plant. This system must begin this monitoring not later than April 1...) The temperature of the disinfected water must be measured once per day at each residual disinfectant... disinfected water must be measured once per day at each chlorine residual disinfectant concentration...

  18. 40 CFR 141.172 - Disinfection profiling and benchmarking.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... appropriate, through the entire treatment plant. This system must begin this monitoring not later than April 1...) The temperature of the disinfected water must be measured once per day at each residual disinfectant... disinfected water must be measured once per day at each chlorine residual disinfectant concentration...

  19. Disinfection protocols to prevent cross-contamination between dental offices and prosthetic laboratories.

    PubMed

    Salvia, Ana Carolina Rodrigues Danzi; Matilde, Fernanda Dos Santos; Rosa, Francine Cristina Silva; Kimpara, Estevão Tomomitsu; Jorge, Antonio Olavo Cardoso; Balducci, Ivan; Koga-Ito, Cristiane Yumi

    2013-10-01

    Control of cross-contamination between dental offices and prosthetic laboratories is of utmost importance to maintain the health of patients and dental office staff. The purpose of this study was to evaluate disinfection protocols, considering antimicrobial effectiveness and damage to the structures of prostheses. Solutions of 1% sodium hypochlorite, 2% chlorhexidine digluconate, 50% vinegar and sodium perborate were evaluated. Specimens were contaminated in vitro with standardized suspensions of Candida albicans, Streptococcus mutans, Escherichia coli, Staphylococcus aureus and Bacillus subtilis spores. Disinfection by immersion for 10 min was performed. Final counts of microorganisms were obtained using the plating method. Results were statistically compared by Kruskal-Wallis ANOVA and Dunn's test. The surface roughness of 40 specimens was analyzed before and after 10 disinfection cycles, and results were compared statistically using Student's t test. The solution of 50% vinegar was as effective as 1% sodium hypochlorite and 2% chlorhexidine against C. albicans, E. coli and S. mutans. The sodium perborate solution showed the lowest antimicrobial effectiveness. Superficial roughness increased after cycles in 1% sodium hypochlorite (p=0.02). Solutions of 1% sodium hypochlorite, 2% chlorhexidine and 50% vinegar were effective for the disinfection of heat-polymerized acrylic specimens. Sodium hypochlorite increased the superficial roughness. Copyright © 2013 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  20. Determination of Benzalkonium Chloride in Commercial Disinfectant Formulations by Quantitative NMR Spectroscopy

    DTIC Science & Technology

    2012-11-01

    treatment protocol for Royal Australian Navy vessels involves dosing with commercial disinfectant solutions containing the biocide benzalkonium...Quantitative NMR Spectroscopy Executive Summary A biofouling treatment protocol for Royal Australian Navy vessels involves dosing with commercial...An existing protocol for the in-water treatment of mussel biofouling within the internal sea water systems of RAN vessels is to dose with a

  1. 9 CFR 96.10 - Uncertified casings; transportation for disinfection; original shipping containers; disposition...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... sodium hydroxide of not less than 95 percent purity to 6 gallons of water, or one 131/2-ounce can to 5 gallons of water. 2 2 Due to the extreme caustic nature of sodium hydroxide solution, and of sodium... least thirty minutes to accomplish disinfection. The containers should then be washed with water...

  2. 9 CFR 96.10 - Uncertified casings; transportation for disinfection; original shipping containers; disposition...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... sodium hydroxide of not less than 95 percent purity to 6 gallons of water, or one 131/2-ounce can to 5 gallons of water. 2 2 Due to the extreme caustic nature of sodium hydroxide solution, and of sodium... least thirty minutes to accomplish disinfection. The containers should then be washed with water...

  3. 9 CFR 96.10 - Uncertified casings; transportation for disinfection; original shipping containers; disposition...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... sodium hydroxide of not less than 95 percent purity to 6 gallons of water, or one 131/2-ounce can to 5 gallons of water. 2 2 Due to the extreme caustic nature of sodium hydroxide solution, and of sodium... least thirty minutes to accomplish disinfection. The containers should then be washed with water...

  4. 9 CFR 96.10 - Uncertified casings; transportation for disinfection; original shipping containers; disposition...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... sodium hydroxide of not less than 95 percent purity to 6 gallons of water, or one 131/2-ounce can to 5 gallons of water. 2 2 Due to the extreme caustic nature of sodium hydroxide solution, and of sodium... least thirty minutes to accomplish disinfection. The containers should then be washed with water...

  5. Microbial resistance to disinfectants: mechanisms and significance

    SciTech Connect

    Hoff, J.C.; Akin, E.W.

    1986-11-01

    Drinking water disinfection provides the final barrier to transmission of a wide variety of potentially waterborne infectious agents including pathogenic bacteria, viruses, and protozoa. These agents differ greatly in their innate resistance to inactivation by disinfectants, ranging from extremely sensitive bacteria to highly resistant protozoan cysts. The close similarity between microorganism inactivation rates and the kinetics of chemical reactions has long been recognized. Ideally, under carefully controlled conditions, microorganism inactivation rates simulate first-order chemical reaction rates, making it possible to predict the effectiveness of disinfection under specific conditions. In practice, changes in relative resistance and deviations from first-order kinetics are caused by a number of factors, including microbial growth conditions, aggregation, and association with particulate materials. The net effect of all these factors is a reduction in the effectiveness and predictability of disinfection processes. To ensure effective pathogen control, disinfectant concentrations and contact times greater than experimentally determined values may be required. Of the factors causing enhanced disinfection resistance, protection by association with particulate matter is the most significant. Therefore, removal of particulate matter is an important step in increasing the effectiveness of disinfection processes.

  6. Contact inactivation of orthopoxviruses by household disinfectants.

    PubMed

    Butcher, W; Ulaeto, D

    2005-01-01

    The aim of this study is to identify common household disinfectants that combine significant activity against the type orthopoxvirus, vaccinia virus with minimal impact in terms of potential toxicity and/or damage to household or personal items. Laboratory scale experiments assessed common disinfectants containing anionic and nonionic detergents, oxygen-based bleach, potassium peroxomonosulfate, chloroxylenol or halogenated phenols. Disinfectants were assessed for their ability to inactivate the virus on contact or after a short incubation period in the presence and absence of foetal bovine serum as a potential interferant. Significant differences were observed ranging from negligible effect of detergents to complete inactivation on contact with chloroxylenol. At least one chloroxylenol-based household disinfectant is available, which inactivates vaccinia virus on contact. In the event of a release or major outbreak of a pathogenic orthopoxvirus there is likely to be significant public demand for disinfectants with activity against these viruses. The identification of common household disinfectants with such activity obviates any requirement to stockpile or distribute laboratory/industrial disinfectants for this purpose.

  7. Hardness and surface roughness of reline and denture base acrylic resins after repeated disinfection procedures.

    PubMed

    Machado, Ana Lucia; Breeding, Larry C; Vergani, Carlos Eduardo; da Cruz Perez, Luciano Elias

    2009-08-01

    Microwave irradiation and immersion in chemical solutions have been recommended for denture disinfection. However, the effect of these procedures on the surface characteristics of denture base and reline resins has not been completely evaluated. The purpose of this study was to evaluate the effect of microwave and chemical disinfection on the Vickers hardness (VHN) and surface roughness (Ra, microm) of 2 hard chairside reline resins (Kooliner, DuraLiner II), and 1 heat-polymerizing denture base resin (Lucitone 550). Specimens (12 x 12 x 3 mm) were divided into 2 control and 4 test groups (n=8). Hardness and roughness measurements were performed after: polymerization and immersion in water (37 degrees C) for 7 days (controls), or repeated exposure to disinfection by immersion in sodium perborate (50 degrees C/10 min) or microwave irradiation (650 W/6 min). Measurements of surface roughness (Ra, microm) and hardness (kg/mm(2)) were analyzed using 3-way ANOVA and Tukey's Honestly Significant Difference (HSD) test (alpha=.05). Microwave and chemical disinfection increased the mean (SD) hardness of Kooliner (from 4.1 to 7.5 kg/mm(2)) and DuraLiner II (from 2.6 to 5.6 kg/mm(2)), whereas Lucitone 550 (14.4 kg/mm(2)) remained unaffected. Disinfection by immersion in sodium perborate increased the surface roughness of DuraLiner II (from 0.13 to 0.26 microm) and Kooliner (from 0.16 to 0.26 microm), regardless of the number of cycles. For Lucitone 550, an increase in roughness was observed after 2 cycles of chemical disinfection (from 0.12 to 0.26 microm). Two cycles of microwave disinfection increased the roughness of both reline resins (DuraLiner II: from 0.13 to 0.22 microm; Kooliner: from 0.16 to 0.24 microm), whereas repeated microwave disinfection increased the roughness of DuraLiner II (from 0.11 to 0.25 microm). Disinfection by immersion in sodium perborate or microwave irradiation did not adversely affect the hardness of all materials evaluated. The effect of both

  8. [Hygiene and methods of decontamination, disinfection and sterilization in dental offices in Yaounde].

    PubMed

    Onana, J; Ngongang, A

    2002-03-01

    Hygiene and asepsis of the dental office depend on medical ethics and legal obligation. The survey done with the participation of 33 practitioners over the 42 practicing in Yaounde allows apprehending the reality of the daily hygiene. The ways of cleaning, decontamination, disinfection or of sterilization of the premises, the dental equipment and instruments, hand-washing, disposable materials and the vaccination protection of the practitioners were analyzed. The cleaning of the floor and door mats is daily (100%); disinfection is done daily in 83% of the departments in all of the centers. The cleaning and disinfection of the dental chair is daily and is done using soap (23%) and/or bleaching-water (56%). Cleaning or disinfection of the suction machine is done with soap (24%) or with bleaching-water (47%). The hand-pieces and the turbines are cleaned and/or disinfected after each usage in (94%) with alcohol (17%) or with bleaching-water (32%) and sterilized with a heat sterilizer (45%), an autoclave(40%) or cold disinfected(15%). The frequency of the treatment of the instruments is well-respected (83%). Nevertheless the products used are very varied and are not always used in the prescribed order. Hand-washing is systematic after each patient; 50% of the practitioners use soap bars or powered soap and 50% use an antiseptic or a disinfectant solutions. With the regard to the vaccination, only 3 practitioners were properly vaccinated against hepatitis B, tetanus, diphtheria, poliomyelitis and tuberculosis. With regard to the protection of the practitioners, 72% do not wear caps, 56% do not wear eyeglasses, 40% do not wear masks, 95% do not use rubber dams, 56% do not disinfect the radiographic films and 37% do not disinfect the impressions; the habitual attire consists of a smock worn over street clothes (78%) and street shoes (90%). The debris is burnt in 35% of the centers. Better knowledge of the different stages (cleaning, decontamination, disinfection or

  9. Cleanliness of portable medical equipment disinfected by nursing staff.

    PubMed

    Havill, Nancy L; Havill, Heather L; Mangione, Elise; Dumigan, Diane G; Boyce, John M

    2011-09-01

    Increased attention has been focused on disinfection by housekeepers, but few data are available on disinfection of equipment by nurses. We used adenosine triphosphate bioluminescence assays and aerobic cultures to assess the cleanliness of portable medical equipment disinfected by nurses between each patient use. We found that the equipment was not being disinfected as per protocol and that education and feedback to nursing are warranted to improve disinfection of medical equipment.

  10. Use of Clinical UV Chamber to Disinfect Dental Impressions: A Comparative Study

    PubMed Central

    Sharma, Sakshi; Kumar, Varun; Gupta, Neelu

    2015-01-01

    Introduction Dental impressions are potential source of infection in a prosthodontic practice. Risk of transmission of infection through saliva, blood etc is considered as hazard for both dentist as well as dental auxiliary staff. A number of methods are currently employed for disinfecting the impressions which are technique sensitive and time consuming. This study focuses on disinfecting impression using dental UV chamber which is commonly employed for storing sterilized instruments. Aim The aim of this invitro study was to evaluate the use of clinical UV chamber to disinfect various impression materials at different time intervals and its comparison with 2% glutaraldehyde using standard immersion technique. Materials and Methods Total sample size of 180 specimens was taken from three different impression materials. The impressions were made from 30 dentulous subjects. A total of ten impressions were made for each impression material i.e. alginate, addition silicone and polyether impression material. Six punch samples were taken from each impression. Out of 6 punch sample, one was kept as control, second was disinfected by immersing in freshly prepared 2% glutaraldehyde solution for 10 minutes and remaining four were exposed to UV rays for 3 minutes, 6 minutes, 10 minutes and 15 minutes using dental UV chamber. Amount of disinfection achieved was evaluated by counting the colonies over the culture plates with the help of digital colony. Results The results showed that the mean CFUs for alginate were found to be i.e. 11797.40 ± 5989.73 (mean ± SD). The mean CFUs for addition silicone impression material was found 7095.40 with a standard deviation of 4268.83 and the mean CFUs for polyether impression material was found to be 2168.92 ± 1676 (mean ± SD). Conclusion For alginate and addition silicone impression material, disinfection was achieved on exposure to UV rays for a period of 10 minutes. However, for polyether impression material 3 minutes of exposure to

  11. Evaluation of disinfectants to prevent mechanical transmission of viruses and a viroid in greenhouse tomato production.

    PubMed

    Li, Rugang; Baysal-Gurel, Fulya; Abdo, Zaid; Miller, Sally A; Ling, Kai-Shu

    2015-01-27

    In recent years, a number of serious disease outbreaks caused by viruses and viroids on greenhouse tomatoes in North America have resulted in significant economic losses to growers. The objectives of this study were to evaluate the effectiveness of commercial disinfectants against mechanical transmission of these pathogens, and to select disinfectants with broad spectrum reactivity to control general virus and viroid diseases in greenhouse tomato production. A total of 16 disinfectants were evaluated against Pepino mosaic virus (PepMV), Potato spindle tuber viroid (PSTVd), Tomato mosaic virus (ToMV), and Tobacco mosaic virus (TMV). The efficacy of each disinfectant to deactivate the pathogen's infectivity was evaluated in replicate experiments from at least three independent experiments. Any infectivity that remained in the treated solutions was assessed through bioassays on susceptible tomato plants through mechanical inoculation using inocula that had been exposed with the individual disinfectant for three short time periods (0-10 sec, 30 sec and 60 sec). A positive infection on the inoculated plant was determined through symptom observation and confirmed with enzyme-linked immunosorbent assay (PepMV, ToMV, and TMV) and real-time reverse transcription-PCR (PSTVd). Experimental data were analyzed using Logistic regression and the Bayesian methodology. Statistical analyses using logistic regression and the Bayesian methodology indicated that two disinfectants (2% Virkon S and 10% Clorox regular bleach) were the most effective to prevent transmission of PepMV, PSTVd, ToMV, and TMV from mechanical inoculation. Lysol all-purpose cleaner (50%) and nonfat dry milk (20%) were also effective against ToMV and TMV, but with only partial effects for PepMV and PSTVd. With the broad spectrum efficacy against three common viruses and a viroid, several disinfectants, including 2% Virkon S, 10% Clorox regular bleach and 20% nonfat dry milk, are recommend to greenhouse facilities

  12. Disinfection methods used in decontamination of bottles used for feeding powdered infant formula.

    PubMed

    Redmond, Elizabeth; Griffith, Christopher J

    2009-01-01

    Infant susceptibility and the risks posed by infections associated with bottle-fed powdered infant formula (PIF) have received increased attention in recent years. Intrinsic contamination of PIF with pathogens has been reported and extrinsic contamination can be introduced from the handler or the environment during reconstitution. Recommended disinfection advice and bottle decontamination have changed in recent years and the aim of this study was to validate the efficacy of four current disinfection methods using bottles that had contained reconstituted PIF spiked with either a representative mixed bacterial culture or specific pathogens. Initially, bottles (n = 6) of reconstituted formula were spiked with 10(5) cfu/ml representative mixed culture. For subsequent experiments, reconstituted formula was spiked with either 10(2) and 10(4) cfu/ml of Enterobacter sakazakii (Cronobacter), Bacillus cereus and Staphylococcus aureus. Before disinfection, bottles were cleaned according to recommended guidelines. Disinfection procedures tested included a hypochlorite-based chemical solution and three heat-based methods. Bottles were sampled in four sites. Before cleaning and disinfection, the inner screw cap and inner-teat were the most heavily contaminated sites with 1.6-7.4 x 10(3) cfu/per-area-sampled; the bottle interior was more contaminated overall with 1.2 x 10(4) cfu/per-area-sampled. After disinfection, adherence to recommended procedures (combined with good hygiene) enabled effective decontamination to be achieved using all methods. Small differences in disinfection ability were not significant (p > 0.05). Cumulatively, 800 sites were sampled and no B. cereus or E. sakazakii were isolated. S. aureus was isolated from 0.1% of sites with one site exceeding 1 cfu/ml. Findings indicate the potential for bottle contamination and that strict adherence to four currently used methods allowed effective decontamination. This highlights the importance of effective consumer

  13. Formation of organic chloramines during water disinfection: chlorination versus chloramination.

    PubMed

    Lee, Wontae; Westerhoff, Paul

    2009-05-01

    Many of the available studies on formation of organic chloramines during chlorination or chloramination have involved model organic nitrogen compounds (e.g., amino acids), but not naturally occurring organic nitrogen in water. This study assessed organic chloramine formation during chlorination and chloramination of 16 natural organic matter (NOM) solutions and 16 surface waters which contained dissolved organic nitrogen (DON). Chlorination rapidly formed organic chloramines within 10 min, whereas chloramination formed organic chloramination much more slowly, reaching the maximum concentration between 2 and 120 h after the addition of monochloramine into the solutions containing DON. The average organic chloramine formation upon addition of free chlorine and monochloramine into the NOM solutions were 0.78 mg-Cl(2)/mg-DON at 10 min and 0.16 mg-Cl(2)/mg-DON at 24h, respectively. Organic chloramine formation upon chlorination and chloramination increased as the dissolved organic carbon/dissolved organic nitrogen (DOC/DON) ratio decreased (i.e., DON contents increased). Chlorination of molecular weight (10,000 Da) fractionated water showed that molecular weight of DON would not impact the amount of organic chloramines produced. Comparison of three different disinfection schemes at water treatment plants (free chlorine, preformed monochloramine, and chlorine/ammonia additions) indicated organic chloramine formation could lead to a possible overestimation of disinfection capacity in many chloraminated water systems that add chlorine followed by an ammonia addition to form monochloramine.

  14. The effect of a range of disinfectants on the dimensional accuracy and stability of some impression materials.

    PubMed

    Jagger, D C; Vowles, R W; McNally, L; Davis, F; O'Sullivan, D J

    2007-03-01

    Disinfection of dental impressions should be considered as a routine procedure in dental surgeries and dental laboratories. Disinfectants can have deleterious effects on some properties of impression materials. The aim of this study was to evaluate the dimensional accuracy and dimensional stability of a model dental stone, reproduced from five commonly used impression materials (Aquasil soft putty/Aquasil Ultra LV; Aquasil Monophase; Aquasil Ultra Heavy; Impregum F and Provil putty/Provil Light CD wash) retained by their adhesives in acrylic resin trays and exposed to three disinfectant solutions (Perform ID; Haz-Tabs and MD 520). Two hundred models were used to investigate the effect of the three disinfectants on the dimensional accuracy of the five impression materials. Five impressions were taken for each impression material for each disinfection treatment group. Measurements were carried out using a High Precision Reflex Microscope. All materials demonstrated a percentage change in dimensions when subjected to no disinfection when compared to the brass master die and all materials demonstrated a percentage change in dimension when subjected to the different disinfection procedures. The results of this study have demonstrated that for all of the materials investigated, the changes in dimensional stability were small in the order of microns. These changes may however be of clinical significance for procedures requiring a high degree of accuracy, for example fixed prosthodontics. The materials respond differently depending on the disinfectant used and it may therefore be appropriate that manufacturers recommend the use of particular disinfectants for their products in order to ensure optimum dimensional accuracy and stability.

  15. Effectiveness of six different disinfectants on removing five microbial species and effects on the topographic characteristics of acrylic resin.

    PubMed

    da Silva, Francine Cristina; Kimpara, Estevão Tomomitsu; Mancini, Maria Nadir Gasparotto; Balducci, Ivan; Jorge, Antonio Olavo Cardoso; Koga-Ito, Cristiane Yumi

    2008-12-01

    The aim of this study was to evaluate the effectiveness of disinfectant solutions (1% sodium hypochlorite, 2% chlorhexidine digluconate, 2% glutaraldehyde, 100% vinegar, tabs of sodium perborate-based denture cleanser, and 3.8% sodium perborate) in the disinfection of acrylic resin specimens (n = 10/group) contaminated in vitro by Candida albicans, Streptococcus mutans, S. aureus, Escherichia coli, or Bacillus subtilis as measured by residual colony-forming unit (CFU). In a separate experiment, acrylic resin was treated with disinfectants to monitor potential effects on surface roughness, Ra (microm), which might facilitate microbial adherence. Three hundred fifty acrylic resin specimens contaminated in vitro with 1 x 10(6) cells/ml suspensions of standard strains of the cited microorganisms were immersed in the disinfectants for 10 minutes; the control group was not submitted to any disinfection process. Final counts of microorganisms per ml were performed by plating method for the evaluation of microbial level reduction. Results were compared statistically by ANOVA and Tukey's test (p< or = 0.05). In a parallel study aiming to evaluate the effect of the tested disinfectant on resin surface, 60 specimens were analyzed in a digital rugosimeter before and after ten cycles of 10-minute immersion in the disinfectants. Measurements of superficial roughness, Ra (mum), were compared statistically by paired t-test (p< or = 0.05). The results showed that 1% sodium hypochlorite, 2% glutaraldehyde, and 2% chlorhexidine digluconate were most effective against the analyzed microorganisms, followed by 100% vinegar, 3.8% sodium perborate, and tabs of sodium perborate-based denture cleanser. Superficial roughness of the specimens was higher after disinfection cycles with 3.8% sodium perborate (p= 0.03) and lower after the cycles with 2% chlorhexidine digluconate (p= 0.04). Within the limits of this experiment, it could be concluded that 1% sodium hypochlorite, 2% glutaraldehyde

  16. Experience in Remote Demolition of the Activated Biological Shielding of the Multi Purpose Research Reactor (MZFR) on the German Karlsruhe Site - 12208

    SciTech Connect

    Eisenmann, Beata; Fleisch, Joachim; Prechtl, Erwin; Suessdorf, Werner; Urban, Manfred

    2012-07-01

    In 2009, WAK Decommissioning and Waste Management GmbH (WAK) became owner and operator of the waste treatment facilities of Karlsruhe Institute of Technology (KIT) as well as of the prototype reactors, the Compact Sodium-Cooled Fast Reactor (KNK) and Multi-Purpose Reactor (MZFR), both being in an advanced stage of dismantling. Together with the dismantling and decontamination activities of the former WAK reprocessing facility since 1990, the envisaged demolishing of the R and D reactor FR2 and a hot cell facility, all governmentally funded nuclear decommissioning projects on the Karlsruhe site are concentrated under the WAK management. The small space typical of prototype research reactors represented a challenge also during the last phase of activated dismantling, dismantling of the activated biological shield of the MZFR. Successful demolition of the biological shield required detailed planning and extensive testing in the years before. In view of the limited space and the ambient dose rate that was too high for manual work, it was required to find a tool carrier system to take up and control various demolition and dismantling tools in a remote manner. The strategy formulated in the concept of dismantling the biological shield by means of a modified electro-hydraulic demolition excavator in an adaptable working scaffolding turned out to be feasible. The following boundary conditions were essential: - Remote exchange of the dismantling and removal tools in smallest space. - Positioning of various supply facilities on the working platform. - Avoiding of interfering edges. - Optimization of mass flow (removal of the dismantled mass from the working area). - Maintenance in the surroundings of the dismantling area (in the controlled area). - Testing and qualification of the facilities and training of the staff. Both the dismantling technique chosen and the proceeding selected proved to be successful. Using various designs of universal cutters developed on the basis of

  17. Automatic environmental disinfection with hydrogen peroxide and silver ions versus manual environmental disinfection with sodium hypochlorite: a multicentre randomized before-and-after trial.

    PubMed

    Mosci, D; Marmo, G W; Sciolino, L; Zaccaro, C; Antonellini, R; Accogli, L; Lazzarotto, T; Mongardi, M; Landini, M P

    2017-10-01

    New technologies for automated disinfection have been developed, including the use of hydrogen peroxide atomized by specific equipment, with associated silver compounds. To compare the effectiveness of an automated disinfection system with hydrogen peroxide <8% and silver ion versus a manual method with 0.5% sodium hypochlorite solution when evaluating the reduction of microbial mesophilic contamination and Clostridium difficile presence; and to evaluate the time required for both of these processes. This was a randomized multicentre trial performed in different hospital wards that had been occupied previously by patients with Clostridium difficile infection. When patients were discharged their rooms were randomized to one of two decontamination arms. The surfaces where sampled using swabs, before and after disinfection. Swab samples were cultured for quantitative detection of microbial mesophilic contamination and qualitative detection of C. difficile. Before disinfection, 13% of surfaces decontaminated with hydrogen peroxide and silver ions and 20% of surfaces decontaminated with sodium hypochlorite showed presence of C. difficile spores. After disinfection, the samples containing C. difficile were 0% (P < 0.001) in the group decontaminated with hydrogen peroxide and silver ions, and were 3% (P < 0.001) in the group decontaminated with sodium hypochlorite. This difference was not statistically significant; nor was the difference in the reduction of the microbial mesophilic contamination. The differences between the groups were not statistically significant; however, the disinfection with hydrogen peroxide and silver ions is preferable due to less dependence on operators. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  18. [Disinfection by-products reduction of combined disinfection by chlorine and monochloramines in distribution system].

    PubMed

    Liu, Jing; Chen, Chao; Zhang, Xiao-Jian

    2009-09-15

    Halogen disinfection by-products of four chlorined disinfection processes with long contact time in distribution system was compared in the work. These four disinfection processes are free chlorine, monochloramines, free chlorine disinfection in clearwelles while chloramines in distribution system, sequential chlorination disinfection with short-term free chlorine plus chloramines. According to the research, free chlorine generates most trihalomethanes (THMs) and haloacetic acids (HAAs) both in clearwells and distribution system, while monochloramines barely yield halogen DBPs. Free chlorine disinfection in clearwelles while chloramines in distribution system could reduce 9.6% of THMs and 42% of HAAs in 24 h contact time of distribution system compared with free chlorine. But free chlorine has contacted with water for 2 h in this process, halogen DBPs have been yielded substantially. Process of sequential chlorination disinfection could control DBPs more effectively due to keeping a short contact time of free chlorine and water. 48% of THMs and 72% of HAAs are reduced in 24h compared with free chlorine. In conclusion, sequential chlorination disinfection is a more effective disinfection process for controlling DBPs and water safety.

  19. [Virucidal activity of disinfectants. Influence of the serum protein upon the virucidal activity of disinfectants].

    PubMed

    Noda, M; Matsuda, S; Kobayashi, M

    2000-08-01

    Five disinfectants were tested for virucidal activity on three DNA viruses and three RNA viruses in the presence or absence of serum protein. Disinfectants of the aldehyde and halogen groups had a virucidal activity on human herpes virus, bovine rhabdo virus, human immunodeficiency virus, human adeno virus, porcine parvo virus, and polio virus. Disinfectants of the invert and amphoteric soap groups, and biganide group had a destructive effect on RNA and DNA viruses possessing an envelope. The presence of serum protein exerted great influence upon the virucidal activity of disinfectants of the invert and amphoteric soap groups.

  20. Residual Structure of Streptococcus mutans Biofilm following Complete Disinfection Favors Secondary Bacterial Adhesion and Biofilm Re-Development

    PubMed Central

    Ohsumi, Tatsuya; Takenaka, Shoji; Wakamatsu, Rika; Sakaue, Yuuki; Narisawa, Naoki; Senpuku, Hidenobu; Ohshima, Hayato; Terao, Yutaka; Okiji, Takashi

    2015-01-01

    Chemical disinfection of oral biofilms often leaves biofilm structures intact. This study aimed to examine whether the residual structure promotes secondary bacterial adhesion. Streptococcus mutans biofilms generated on resin-composite disks in a rotating disc reactor were disinfected completely with 70% isopropyl alcohol, and were again cultured in the same reactor after resupplying with the same bacterial solution. Specimens were subjected to fluorescence confocal laser scanning microscopy, viable cell counts and PCR-Invader assay in order to observe and quantify secondarily adhered cells. Fluorescence microscopic analysis, particularly after longitudinal cryosectioning, demonstrated stratified patterns of viable cells on the disinfected biofilm structure. Viable cell counts of test specimens were significantly higher than those of controls, and increased according to the amount of residual structure and culture period. Linear regression analysis exhibited a high correlation between viable and total cell counts. It was concluded that disinfected biofilm structures favored secondary bacterial adhesion. PMID:25635770

  1. Residual structure of Streptococcus mutans biofilm following complete disinfection favors secondary bacterial adhesion and biofilm re-development.

    PubMed

    Ohsumi, Tatsuya; Takenaka, Shoji; Wakamatsu, Rika; Sakaue, Yuuki; Narisawa, Naoki; Senpuku, Hidenobu; Ohshima, Hayato; Terao, Yutaka; Okiji, Takashi

    2015-01-01

    Chemical disinfection of oral biofilms often leaves biofilm structures intact. This study aimed to examine whether the residual structure promotes secondary bacterial adhesion. Streptococcus mutans biofilms generated on resin-composite disks in a rotating disc reactor were disinfected completely with 70% isopropyl alcohol, and were again cultured in the same reactor after resupplying with the same bacterial solution. Specimens were subjected to fluorescence confocal laser scanning microscopy, viable cell counts and PCR-Invader assay in order to observe and quantify secondarily adhered cells. Fluorescence microscopic analysis, particularly after longitudinal cryosectioning, demonstrated stratified patterns of viable cells on the disinfected biofilm structure. Viable cell counts of test specimens were significantly higher than those of controls, and increased according to the amount of residual structure and culture period. Linear regression analysis exhibited a high correlation between viable and total cell counts. It was concluded that disinfected biofilm structures favored secondary bacterial adhesion.

  2. Pilot Study for UVA-LED Disinfection of Escherichia coli in Water for Space and Earth Applications

    NASA Technical Reports Server (NTRS)

    Ragolta, Carolina

    2010-01-01

    To test the efficacy of UVA-LED disinfection, a solution of Escherichia coli was pumped through a modified drip flow reactor at a flow rate of 1 ml/min. The experiment was conducted in a controlled environment chamber to ensure that temperature did not cause disinfection. The reactor featured three wells with different treatments: UVA-LED irradiation, UVA-LEDs with Ti02, and UVA-LEDs with nanosilver. Samples from each well were taken throughout a 340 hour period, inactivated, assayed, and analyzed for E. coli disinfection. Results of the duplicate experiments indicated longer exposure times are needed for UVA-LED disinfection of E. coli in water. Further research would consider a longer sampling period and different test conditions, such as increased contact area and various flow rates.

  3. Efficacy of eight commercial disinfectants against Microsporum canis and Trichophyton spp. infective spores on an experimentally contaminated textile surface.

    PubMed

    Moriello, Karen A; Kunder, Darcie; Hondzo, Hanna

    2013-12-01

    An important part of treatment of dermatophytosis is the removal of infective material and decontamination of the environment. It is recognized that the role of disinfectants is to kill infective material not removed during the mechanical removal of debris and gross cleaning steps. A widely used disinfectant in the home is a dilute solution of sodium hypochlorite. To determine whether over-the-counter products, particularly ready-to-use formulations, with label claim as fungicidal are effective against Microsporum or Trichophyton spores isolated from cat hair. Eight commercial disinfectants were tested in vitro for fungicidal efficacy using three different trials and a 10 min contact time, as follows: a standard 1:10 spore dilution suspension test; 1 and 5 mL of disinfectant solution applied to contaminated gauze fabric; and, to simulate home use, one and five sprays of disinfectant applied to contaminated gauze. Good efficacy was defined as a product that completely inhibited growth. All products completely inhibited growth in the suspension test. Four of eight products showed complete inhibition of growth of both pathogens on the textile test after 1 mL or one spray; however, all eight products showed complete inhibition of pathogen growth after 5 mL or five sprays. Aggressive removal of contaminated material followed by thorough application of commercial ready-to-use disinfectants labelled as fungicidal against Trichophyton mentagrophytes are alternatives to dilute sodium hypochlorite. © 2013 ESVD and ACVD.

  4. Evaluation of disinfectant efficacy against hepatitis C virus using a RT-PCR-based method.

    PubMed

    Charrel, R N; de Chesse, R; Decaudin, A; De Micco, P; de Lamballerie, X

    2001-10-01

    The methods traditionally used to evaluate the antiviral activity of antiseptics and disinfectants are based on cell cultures. However, such methods are not applicable to non-cultivable viruses such as hepatitis C (HCV). Therefore, in this case, virucidal activity is normally tested using surrogate viruses able to grow in cell culture. This paper describes a RT-PCR method for testing antiseptic/disinfectant activity against HCV, as a model for non-cultivable viruses. A chlorine-based agent used for skin and tissues, and a 2% glutaraldehyde solution used for endoscope disinfection, were the test materials. The results are discussed in the light of the use of these agents. The method is simple, fast and inexpensive, and could be used for tests on other viruses with minor modification. Copyright 2001 The Hospital Infection Society.

  5. Disinfectant storage media and composite/metal bond strength.

    PubMed

    Williams, V D; Díaz-Arnold, A M; Fotos, P G

    1994-08-01

    To evaluate the effect of three disinfection procedures on the tensile bond strength of Panavia resin composite cement. Alloy cylinders were bonded and stored in: (1) 0.2% chlorhexidine; (2) 2% activated glutaraldehyde; (3) distilled water and sterilized with ethylene oxide; and (4) distilled water. Solutions were monitored for bacterial cultures and pH changes regularly for 90 days after which all samples were tested to tensile failure. ANOVA showed no significant difference between mean group bond strengths. A direct positive correlation was demonstrated between solution pH and bond strengths (r = 0.98). All groups were found to represent effective methods for preventing bacterial growth in storage solutions during long term cement bonding studies.

  6. Photoactivated disinfection (PAD) in endodontics: an in vitro microbiological evaluation.

    PubMed

    Poggio, Claudio; Arciola, Carla Renata; Dagna, Alberto; Florindi, Filippo; Chiesa, Marco; Saino, Enrica; Imbriani, Marcello; Visai, Livia

    2011-09-01

    The objective of the present study was the in vitro evaluation by MTT test of the antimicrobial effect of photoactivated disinfection (PAD) and, comparatively, of a conventional 5.25% NaOCl irrigating solution. Enterococcus faecalis, Streptococcus mutans and Streptococcus sanguis strains were selected for the test. Freshly extracted single-rooted human teeth were endodontically treated, inoculated with bacterial strains and then divided into different groups, each of them treated with PAD, with PAD plus 0.5% NaOCl solution, with TBO, with PAD for longer time and with 5% NaOCl solution (positive control). The results were significantly different among the various groups, and for Enterococcus faecalis, Streptococcus mutans and Streptococcus sanguis. PAD applied for a longer time (in respect to manufacturer's instructions) or PAD associated to 5% NaOCl showed the significantly higher antibacterial effects.

  7. Disinfection efficacy of organic chloramines.

    PubMed

    Donnermair, Martina M; Blatchley, Ernest R

    2003-04-01

    The disinfection efficacies of model organic chloramines were investigated. Twenty amino acids and two nucleic acid bases were chlorinated separately with sodium hypochlorite at a Cl:N molar ratio of 0.4:1, and were then used to treat an E. coli suspension for 60 min. DPD/FAS titration was carried out to obtain the concentration of the chlorinated nitrogenous organic compounds as a function of time. In addition, membrane introduction mass spectrometry (MIMS) was used to quantify inorganic chloramines (mono-, di-, and trichloramine). The results of these experiments showed that the organic chloramines examined in this research had little or no effect on the viability of E. coli. MIMS analyses demonstrated that there was no quantifiable formation of inorganic chloramines when the organic nitrogen compounds were chlorinated. Copyright 2002 Elsevier Science Ltd.

  8. The role of phytoplankton as pre-cursors for disinfection by-product formation upon chlorination.

    PubMed

    Tomlinson, Adam; Drikas, Mary; Brookes, Justin D

    2016-10-01

    Water quality remains one of the greatest concerns with regards to human health. Advances in science and technology have resulted in highly efficient water treatment plants, significantly reducing diseases related to waterborne pathogenic microorganisms. While disinfection is critical to mitigate pathogen risk to humans, the reactions between the disinfectant and dissolved organic compounds can lead to the formation of chemical contaminants called disinfection by-products (DBPs). DBPs have been related to numerous health issues including birth defects and cancer. The formation of disinfection by-products occurs due to the reaction of oxidants and natural organic matter. DBP precursors are derived from anthropogenic sources including pharmaceuticals and chemical waste, the breakdown of vegetation from external catchment sources (allochthonous) and internally derived sources including phytoplankton (autochthonous). Current literature focuses on the contribution of allochthonous sources towards the formation of DBPs, however, the recalcitrant nature of hydrophilic phytoplankton derived organic matter indicates that autochthonous derived organic carbon can significantly contribute to total DBP concentrations. The contribution of phytoplankton to the formation of DBPs is also influenced by cellular exudation rates, chemical composition, environmental conditions and the physical and chemical conditions of the solution upon disinfection. Formation of DBPs is further influenced by the presence of cyanobacteria phyla due to their notoriety for forming dense blooms. Management of DBP formation can potentially be improved by reducing cyanobacteria as well as DBP precursors derived from other phytoplankton. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. [Disinfection and recontamination of rigid endoscopes: improved safety using an immersion quiver system].

    PubMed

    Rohrmeier, C; Strutz, J; Schneider-Brachert, W

    2014-10-01

    In Otorhinolaryngology, rigid endoscopes are used daily at a high frequency. There is no consensus for reprocessing these medical instruments. Often immersion disinfection procedures are used. The present study examined the possible risk of recontamination by this disinfection method and investigated the possibility of avoiding this risk by using a new immersion quiver system. Using coloured markers, a possible contact of the endoscope with the top edges of quivers of different diameters during endoscope removal was tested for. In addition, it was evaluated whether Staphylococcus aureus transfer is possible via this route. The same methodology was applied to a new immersion quiver system. Whenever removing the rigid endoscopes from the conventional quiver, these touched the top of the quiver, regardless of its diameter. A transfer of Staphylococcus aureus from the quiver to the endoscope via this route could be detected in five out of eight attempts. During endoscope removal from the new immersion quiver system, no contact of the endoscope with the outer quiver occurred in 20 passes. In none of eight trials was a transfer of Staphylococcus aureus from previously contaminated immersion quivers to the endoscope shown; all immersion quivers were sterile after disinfection. After conventional immersion disinfection, recontamination of rigid endoscopes by a contaminated quiver edge is possible. An immersion quiver system can resolve this risk of recontamination easily, by decontaminating not only the endoscope, but also the immersion quiver (inner quiver) itself in the disinfectant solution.

  10. Performic acid (PFA): tests on an advanced primary effluent show promising disinfection performance.

    PubMed

    Gehr, R; Chen, D; Moreau, M

    2009-01-01

    Performic acid, or PFA (CH(2)O(3)), is a well-known oxidizing agent and disinfectant in the medical field and food industry. It has recently become available on a commercial scale for potential use in wastewater disinfection. This study investigated its application to an advanced primary effluent which is recalcitrant to disinfection by UV and peracetic acid (PAA). Methods were developed for determining PFA concentrations in stock solutions as well as in residual concentrations in the wastewater. Batch and continuous-flow pilot studies showed a correlation between log fecal coliform removals and PFA doses. A PFA dose of approximately 3.4 mg/L and a contact time of 45 minutes could achieve 3-logs removal, and almost total disinfection could be achieved using a dose of 6 mg/L. The by-products of PFA addition are hydrogen peroxide and formic acid (CHOOH), neither of which is considered to be toxic to aquatic fauna at the doses required for disinfection.

  11. Analysis of the sporicidal activity of chlorine dioxide disinfectant against Bacillus anthracis (Sterne strain).

    PubMed

    Chatuev, B M; Peterson, J W

    2010-02-01

    Routine surface decontamination is an essential hospital and laboratory procedure, but the list of effective, noncorrosive disinfectants that kill spores is limited. We investigated the sporicidal potential of an aqueous chlorine dioxide solution and encountered some unanticipated problems. Quantitative bacteriological culture methods were used to determine the log(10) reduction of Bacillus anthracis (Sterne strain) spores following 3min exposure to various concentrations of aqueous chlorine dioxide solutions at room temperature in sealed tubes, as well as spraying onto plastic and stainless steel surfaces in a biological safety cabinet. Serial 10-fold dilutions of the treated spores were then plated on 5% sheep blood agar plates, and the survivor colonies were enumerated. Disinfection of spore suspensions with aqueous chlorine dioxide solution in sealed microfuge tubes was highly effective, reducing the viable spore counts by 8log(10) in only 3min. By contrast, the process of spraying or spreading the disinfectant onto surfaces resulted in only a 1log(10) kill because the chlorine dioxide gas was rapidly vaporised from the solutions. Full potency of the sprayed aqueous chlorine dioxide solution was restored by preparing the chlorine dioxide solution in 5% bleach (0.3% sodium hypochlorite). The volatility of chlorine dioxide can cause treatment failures that constitute a serious hazard for unsuspecting users. Supplementation of the chlorine dioxide solution with 5% bleach (0.3% sodium hypochlorite) restored full potency and increased stability for one week.

  12. Analysis of the sporicidal activity of chlorine dioxide disinfectant against Bacillus anthracis (Sterne strain)

    PubMed Central

    Chatuev, B.A.; Peterson, J.W.

    2009-01-01

    Summary Routine surface decontamination is an essential hospital and laboratory procedure, but the list of effective, noncorrosive disinfectants that kill spores is limited. We investigated the sporicidal potential of an aqueous chlorine dioxide solution and encountered some unanticipated problems. Quantitative bacteriological culture methods were used to determine the log10 reduction of Bacillus anthracis (Sterne strain) spores following 3 min exposure to various concentrations of aqueous chlorine dioxide solutions at room temperature in sealed tubes, as well as spraying onto plastic and stainless steel surfaces in a biological safety cabinet. Serial 10-fold dilutions of the treated spores were then plated on 5% sheep blood agar plates, and the survivor colonies were enumerated. Disinfection of spore suspensions with aqueous chlorine dioxide solution in sealed microfuge tubes was highly effective, reducing the viable spore counts by 8 log10 in only 3 min. By contrast, the process of spraying or spreading the disinfectant onto surfaces resulted in only a 1 log10 kill because the chlorine dioxide gas was rapidly vaporised from the solutions. Full potency of the sprayed aqueous chlorine dioxide solution was restored by preparing the chlorine dioxide solution in 5% bleach (0.3% sodium hypochlorite). The volatility of chlorine dioxide can cause treatment failures that constitute a serious hazard for unsuspecting users. Supplementation of the chlorine dioxide solution with 5% bleach (0.3% sodium hypochlorite) restored full potency and increased stability for one week. PMID:20061062

  13. ALTERNATIVE DISINFECTION FOR DRINKING WATER TREATMENT

    EPA Science Inventory

    During a one-yr study at Jefferson Parish, La., the chemical, microbiological, and mutagenic effects os using the major drinkgin water disinfectants (chlorine, chlorine dioxide, chloramine, ozone) were evaluated. Tests were performed on samples collected from various treatment s...

  14. ALTERNATIVE DISINFECTANTS FOR DRINKING WATER TREATMENT

    EPA Science Inventory

    During a one-year study at Jefferson Parish, Louisiana the chemical, microbiological, and mutagenic effects of using the major drinking water disinfectants (chlorine, chlorine dioxide, chloramine, ozone) were evaluated. ests were performed on samples collected from various treatm...

  15. Disinfection, sterilization, and antisepsis: An overview.

    PubMed

    Rutala, William A; Weber, David J

    2016-05-02

    All invasive procedures involve contact by a medical device or surgical instrument with a patient's sterile tissue or mucous membranes. The level of disinfection or sterilization is dependent on the intended use of the object: critical (items that contact sterile tissue such as surgical instruments), semicritical (items that contact mucous membrane such as endoscopes), and noncritical (devices that contact only intact skin such as stethoscopes) items require sterilization, high-level disinfection and low-level disinfection, respectively. Cleaning must always precede high-level disinfection and sterilization. Antiseptics are essential to infection prevention as part of a hand hygiene program as well as several other uses such as surgical hand antisepsis and pre-operative skin preparation.

  16. Wastewater Disinfectants: Many Called--Few Chosen

    ERIC Educational Resources Information Center

    Smith, James W.

    1978-01-01

    Gives a comparative study of disinfectants used to rid wastewater of pathogens. Concentrates on the effects of chlorine and ozone, with some mention of ultra-violet irradiation, bromine chloride, and chlorine dioxide. (MA)

  17. Travelers' Health: Water Disinfection for Travelers

    MedlinePlus

    ... with and use simple methods to ensure safe drinking water. Several methods are scalable and some can be ... supplemented with filtration to remove resistant oocysts from drinking water. Cloudy water contains substances that will neutralize disinfectant, ...

  18. A simple device for disinfecting endoscopes.

    PubMed

    Wagenvoort, J H; van Blankenstein, M; Kooyman-Op de Hoek, G; Boks, A L; van Oudenaarde, P H

    1986-01-01

    A method for disinfecting fibreoptic endoscopes with povidone-iodine and a simple cleaning device, consisting of a curved glass pipe and a peristaltic pump is described. If properly employed the system produces satisfactory results.

  19. Wastewater Disinfectants: Many Called--Few Chosen

    ERIC Educational Resources Information Center

    Smith, James W.

    1978-01-01

    Gives a comparative study of disinfectants used to rid wastewater of pathogens. Concentrates on the effects of chlorine and ozone, with some mention of ultra-violet irradiation, bromine chloride, and chlorine dioxide. (MA)

  20. Studies on Disinfection of Clinical Thermometers

    PubMed Central

    Wright, Eleanore S.; Mundy, R. A.

    1961-01-01

    A study was made of the chemical disinfection of oral thermometers used by patients with active pulmonary tuberculosis. Only 10% of these thermometers were found to be contaminated with acid-fast bacilli. Because of this small number, the use of a phenol coefficient type test with Mycobacterium tuberculosis was suggested as an alternative method for evaluating tuberculocidal activity. These data, in conjunction with data from Part I of these studies dealing with disinfection of oral thermometers from a general hospital, were the criteria used to judge the efficacy of the disinfectants. It was concluded that 70% ethyl alcohol, 2% phenolic no. 1, and 3% phenolic no. 3 were reliable disinfectants for thermometers. Fifty per cent ethyl alcohol, 2% phenolic no. 2, 2% iodophor (300 ppm available iodine), and 0.1% benzalkonium chloride, aqueous or tincture, were unreliable. PMID:14008427

  1. Disinfection of Burkholderia pseudomallei in potable water.

    PubMed

    Howard, Kay; Inglis, Timothy J J

    2005-03-01

    The effect of chlorine, monochloramine and UV disinfection on the water-borne pathogen Burkholderia pseudomallei was assessed. Persistence of B. pseudomallei was verified by MPN involving a one-step recovery procedure. Chlorine proved the most effective disinfectant with a 99.99% reduction of a 10(6) CFU/mL pure bacterial culture followed by 99.9% reduction by monochloramine and 99% reduction by UV. Co-culture of B. pseudomallei with Acanthamoeba astronyxis was found to greatly enhance survival of B. pseudomallei in the presence of all disinfecting agents tested. For example, when amoebae were present 100 times more monochloramine was required to maintain the disinfectant efficacy. Given the results obtained from these co-culture experiments, more research is needed to investigate the role of amoeba and biofilms in survival of B. pseudomallei in potable water.

  2. Antiviral activity of alcohol for surface disinfection.

    PubMed

    Moorer, W R

    2003-08-01

    Bacteria and viruses from the patient's mouth travel with dental splatter and spills. A surface disinfectant should possess antiviral activity as well as antibacterial action. Because of frequent and 'open' application in the dental office, such a disinfectant should be non-toxic, non-allergenic and safe for the hygienist. It now appears that high-concentration alcohol mixtures (i.e. 80% ethanol + 5% isopropanol) are not only excellent antibacterials, but quickly inactivate HIV as well as hepatitis B and hepatitis C viruses. Compared to alternative surface disinfectants, use of high-concentration alcohol for the spray-wipe-spray method of surface disinfection in dentistry appears safe and efficient. However, dried matter should be wiped and hydrated first.

  3. Environmental Cleaning and Disinfecting for MRSA

    MedlinePlus

    ... difference between cleaners, sanitizers, and disinfectants? Cleaners or detergents are products that are used to remove soil, ... germs (like bacteria, viruses, and fungi). Cleaners or detergents work by washing the surface to lift dirt ...

  4. Impact of chlorinated disinfection on copper corrosion in hot water systems

    NASA Astrophysics Data System (ADS)

    Montes, J. Castillo; Hamdani, F.; Creus, J.; Touzain, S.; Correc, O.

    2014-09-01

    In France, hot water quality control inside buildings is occasionally ensured by disinfection treatments using temperature increases or addition of sodium hypochlorite (between 0.5 ppm and 1 ppm residual free chlorine). This disinfectant is a strong oxidiser and it could interact with metallic pipes usually used in hot water systems. This work deals with the study of the impact of these treatments on the durability of copper pipes. The objective of this work was to investigate the influence of sodium hypochlorite concentration and temperature on the copper corrosion mechanism. Copper samples were tested under dynamic and static conditions of ageing with sodium hypochlorite solutions ranging from 0 to 100 ppm with temperature at 50 °C and 70 °C. The efficiency of a corrosion inhibitor was investigated in dynamic conditions. Visual observations and analytical analyses of the internal surface of samples was studied at different ageing duration. Corrosion products were characterised by X-ray diffraction and Raman spectroscopy. Temperature and disinfectant were found to considerably affect the copper corrosion mechanism. Surprisingly, the corrosiveness of the solution was higher at lower temperatures. The temperature influences the nature of corrosion products. The protection efficiency is then strongly depend on the nature of the corrosion products formed at the surface of copper samples exposed to the aggressive solutions containing different concentration of disinfectant.

  5. Disinfection of flexible fiberoptic laryngoscopes after in vitro contamination with Staphylococcus aureus and Candida albicans.

    PubMed

    Chang, Dennis; Florea, Andrew; Rowe, Mark; Seiberling, Kristin A

    2012-02-01

    To determine the efficacy of various cleaning and disinfective methods in reducing bacterial and fungal load on flexible fiberoptic laryngoscopes (FFLs). In vitro model. Flexible fiberoptic laryngoscopes contaminated with Staphylococcus aureus and Candida albicans. Contamination with S aureus and C albicans was separately induced on FFLs, which were then disinfected with different protocols: 20-, 15-, 10-, and 5-minute soaks in ortho-phthalaldehyde (Cidex OPA; Johnson & Johnson) with or without presoaking in an enzymatic soap solution for 5 minutes; an isolated 5-minute soak in an enzymatic soap solution; a 30-second wipe with antibacterial soap and water; a 30-second wipe with isopropyl alcohol; a 30-second wipe with antibacterial soap, followed by a 30-second scrub with isopropyl alcohol; and a 30-second wipe with germicidal cloth, all accompanied by previous rinsing with 30 seconds of running tap water. All protocols except the isolated 5-minute soak in enzymatic soap solution were successful in completely disinfecting the FFLs after experimental contamination with S aureus or C albicans. Various different cleaning methods appeared to properly disinfect FFLs after inoculation with S aureus and C albicans in an in vitro model.

  6. Optimization of fixed titanium dioxide film on PET bottles and visual indicator for water disinfection

    NASA Astrophysics Data System (ADS)

    Heredia-Munoz, Manuel Antonio

    Water is perhaps the most important resource that sustains human life. According to the World Health Organization (WHO), almost two billion people do not have access to the required water that is needed to satisfy their daily needs and one billion do not have access to clean sources of water for consumption, most of them living in isolated and poor areas around the globe. Poor quality water increases the risk of cholera, typhoid fever and dysentery, and other water-borne illness making this problem a real crisis that humankind is facing. Several water disinfection technologies have been proposed as solutions for this problem. Solar water disinfection using TiO2 coated PET bottles was the alternative that is studied in this work. This technology does not only inactivate bacteria but also disintegrates organic chemicals that can be present in water. The objectives of this work address the optimization of the TiO 2 coated PET bottles technologies. The improvement on the bottle coating process, using two coats of 10% W/V of TiO2 in a solution of vinegar and sodium bicarbonate to form the TiO2 film, the use of a different indigo carmine (1.25 X 10-1mg/pill) concentration in the pill indicator of contamination, the increase of the disinfection rate through shaking the bottles, degradation under intermittent UV radiation and the effect of bottle size on photocatalytic water disinfection were among the most important findings. A new mathematical model that describes better photocatalytic water disinfection in TiO2 coated bottles and simulates water disinfection under different working conditions was another important achievement. These results can now be used to design a strategy for disseminating this technology in areas where it is required and, in that way, generate the greatest positive impact on the people needing safe drinking water.

  7. [Elimination of microscopic filamentous fungi with disinfectants].

    PubMed

    Laciaková, A; Laciak, V

    1994-01-01

    The antifungal effectivity of three single-component (Persteril, Septonex, Glutaraldehyd) and of three combined (Persteril+Septonex, Pesteril+Glutaraldehyd, Glutaraldehyd+Septonex) commercially available disinfectants was monitored by the diffuse method on five fen of the microscopic filamentous fungi Aspergillus alternata, Aspergillus niger, Mucor fragillis, Fusarium moniliforme, Penicillium glabrum. The highest antifungal activity was observed in 2% Persteril while 2% Persteril + 1% Septonex were the most effective among the combined disinfectants. M. fragilis was the most resistant strain.

  8. New developments in disinfection and sterilization.

    PubMed

    Wallace, Craig A

    2016-05-02

    A review of regulatory clearances for selected new sterilization and disinfection products for the period January 2012-June 2015 indicates continued leverage of established technologies for steam and low-temperature sterilization, and high-level disinfection. New products in these areas were typically modified and improved versions of existing products, with the exception of a new combination hydrogen peroxide/ozone sterilizer. Development of new low-temperature sterilization technologies to address continued evolution of complex medical devices is expected to continue.

  9. An environmental disinfection odyssey: evaluation of sequential interventions to improve disinfection of Clostridium difficile isolation rooms.

    PubMed

    Sitzlar, Brett; Deshpande, Abhishek; Fertelli, Dennis; Kundrapu, Sirisha; Sethi, Ajay K; Donskey, Curtis J

    2013-05-01

    OBJECTIVE. Effective disinfection of hospital rooms after discharge of patients with Clostridium difficile infection (CDI) is necessary to prevent transmission. We evaluated the impact of sequential cleaning and disinfection interventions by culturing high-touch surfaces in CDI rooms after cleaning. DESIGN. Prospective intervention. SETTING. A Veterans Affairs hospital. INTERVENTIONS. During a 21-month period, 3 sequential tiered interventions were implemented: (1) fluorescent markers to provide monitoring and feedback on thoroughness of cleaning facility-wide, (2) addition of an automated ultraviolet radiation device for adjunctive disinfection of CDI rooms, and (3) enhanced standard disinfection of CDI rooms, including a dedicated daily disinfection team and implementation of a process requiring supervisory assessment and clearance of terminally cleaned CDI rooms. To determine the impact of the interventions, cultures were obtained from CDI rooms after cleaning and disinfection. RESULTS. The fluorescent marker intervention improved the thoroughness of cleaning of high-touch surfaces (from 47% to 81% marker removal; P < .0001). Relative to the baseline period, the prevalence of positive cultures from CDI rooms was reduced by 14% (P=.024), 48% (P <.001), and 89% (P=.006) with interventions 1, 2, and 3, respectively. During the baseline period, 67% of CDI rooms had positive cultures after disinfection, whereas during interventions periods 1, 2, and 3 the percentages of CDI rooms with positive cultures after disinfection were reduced to 57%, 35%, and 7%, respectively. CONCLUSIONS. An intervention that included formation of a dedicated daily disinfection team and implementation of a standardized process for clearing CDI rooms achieved consistent CDI room disinfection. Culturing of CDI rooms provides a valuable tool to drive improvements in environmental disinfection.

  10. Electrochemically Generated Oxidant Disinfection in the Use of Individual Water Purification Devices

    DTIC Science & Technology

    2006-03-01

    Journal of Agricultural and Food Chemistry , 50(1), 209-212. 4. Morita, C., et. al., 2000. Disinfection potential of...Investigation of the Presence of OH Radicals in Electrolyzed NaCl Solution by Electron Spin Resonance Spectroscopy. Journal of Agricultural and Food Chemistry , 53...Studies of Electrolyzed NaCl Solution Using 5,5-Dimethyl-1- pyrroline-N-oxide as a Spin Trapping Agent. Journal of Agricultural

  11. Electrochemical disinfection of biologically treated wastewater from small treatment systems by using boron-doped diamond (BDD) electrodes--contribution for direct reuse of domestic wastewater.

    PubMed

    Schmalz, Viktor; Dittmar, Thomas; Haaken, Daniela; Worch, Eckhard

    2009-12-01

    The aim of the study was to demonstrate the application potential of boron-doped diamond electrodes (BDD) in electrochemical disinfection of biologically treated sewage for direct recycling of domestic wastewater. Discontinuous bulk disinfection experiments with secondary effluents and model solutions were performed to investigate the influence of operating conditions and wastewater parameters on disinfection efficiency and formation of disinfection by-products (adsorbable organically bound halogens, AOX). The inactivation rate accelerates with increasing current density caused by a faster generation of electrochemical oxidants (ECO). It could be shown that the effect of OH radicals in case of the direct electrochemical disinfection of chloride-containing secondary effluents with BDD is negligible because of their fast reaction with typical radical scavengers. The dominating role of electrochemically generated free chlorine in the disinfection process could be explicitly verified. It could be also shown that the disinfection efficiency is strongly affected by the specific wastewater parameters temperature and pH. These effects can be explained by the behaviour of the reactive species. The migration-controlled generation of ECO can be accelerated under turbulent hydrodynamic conditions. The formation of disinfection by-products (AOX) correlates with the introduced electric charge Q applied per volume and is independent of the applied current density.

  12. [Behavior of disinfectant substances in comparisons of bacterial strains].

    PubMed

    Riolo, U; Pandiani, I; Finzi, G

    1982-01-01

    Following a brief of the main requisites of disinfectants, the solutions tested during research are listed: 1) Ethyl alcohol denatured at 70 degrees C. 2) A hydro-alcoholic solution of 0,20% Benzalkonium chloride (F.U.) in association with 0.15% 1-Benzyl-3 [3-Dimethylammoniopropoxy]-1 H-indazol HCl. 3) An acetonic hydro-alcoholic solution of 0.1% Benzoxonium chloride, a water solution of 1% Polyvinylpyrrolidone-iodine (P.V.P.-I), a water solution of 0.5% Chlorhexidine gluconate, and a hydro-alcoholic solution of 0.17% Benzalkonium chloride. The technique used (modified contact test) is illustrated and the results analysed in detail. The best results absolutely were obtained by applying Ethyl alcohol denatured at 70 degrees C and P.V.P.-I in a water solution at a concentration of 1%. Some problem must, however, be borne in mind when using such substances (first, denaturing of proteins, second, action curtailed by temperature). Best results among the Q.A.C. were obtained with the hydro-alcoholic solution of an association of 0.20% Benzalkonium chloride (F.U.) and 0.15% 1-Benzyl-3 [3-Dimethylammoniopropoxy]-1 H-indazol HCl.

  13. Possible monitoring requirements for the disinfectants and disinfection by-products (D/DBP) regulations

    SciTech Connect

    Not Available

    1993-01-01

    The monitoring requirements presented in the report were developed by EPA before a negotiated Disinfectants and Disinfection By-Products (D/DBP) rule was considered. The framework described herein may be substantially changed as a result of the negotiated rulemaking process. The document is useful to consider in developing various monitoring options during the negotiated rulemaking process.

  14. [Is resistance to disinfectants a mandatory feature of a hospital strain of causative agents of nosocomial purulent-septic infections?].

    PubMed

    Sergevnin, V I; Zueva, N G; Kliukina, T V; Volkova, E O

    2013-01-01

    Evaluate resistance to working solutions of disinfectants by Staphylococcus haemolyticus and Klebsiella pneumoniae isolated from newborns and hospital environment objects of obstetric hospital during registration of group purulent-septic infections (PSI). Analysis of 2 epidemic situations on PSI morbidity of newborns caused by S. haemolyticus and K. pneumoniae was carried out. Sensitivity to antibiotics of S. haemolyticus and K. pneumoniae strains isolated from newborns and hospital environment was studied by disc-diffusion method and genotyping of K. pneumoniae--by using polymerase chain reaction with universal primer M 13 (RAPD-PCR). Sensitivity of S. haemolyticus and K. pneumoniae to working solutions of disinfectants was determined on test-surfaces (glass, metal, plastic, wood, oilcloth). The detected identity of antibiotic phenotype of S. haemolyticus and K. pneumoniae strains as well as genotype of K. pneumoniae strains combined with registration of group PSI morbidity among newborns confirms that the circulating strains (clones) of the causative agents were hospital. S. haemolyticus and K. pneumoniae strains in most cases were sensitive to working solutions of disinfectants. Resistance of causative agents of nosocomial PSI to disinfectants is not an unconditional feature of a hospital strain, and concurrence of resistance profile of microorganisms to disinfectant preparations--a mandatory feature of the presence of epidemiologic connection between the diseased.

  15. Inactivation of an enterovirus by airborne disinfectants

    PubMed Central

    2013-01-01

    Background The activity of airborne disinfectants on bacteria, fungi and spores has been reported. However, the issue of the virucidal effect of disinfectants spread by fogging has not been studied thoroughly. Methods A procedure has been developed to determine the virucidal activity of peracetic acid-based airborne disinfectants on a resistant non-enveloped virus poliovirus type 1. This virus was laid on a stainless carrier. The products were spread into the room by hot fogging at 55°C for 30 minutes at a concentration of 7.5 mL.m-3. Poliovirus inoculum, supplemented with 5%, heat inactivated non fat dry organic milk, were applied into the middle of the stainless steel disc and were dried under the air flow of a class II biological safety cabinet at room temperature. The Viral preparations were recovered by using flocked swabs and were titered on Vero cells using the classical Spearman-Kärber CPE reading method, the results were expressed as TCID50.ml-1. Results The infectious titer of dried poliovirus inocula was kept at 105 TCID50.mL-1 up to 150 minutes at room temperature. Dried inocula exposed to airborne peracetic acid containing disinfectants were recovered at 60 and 120 minutes post-exposition and suspended in culture medium again. The cytotoxicity of disinfectant containing medium was eliminated through gel filtration columns. A 4 log reduction of infectious titer of dried poliovirus inocula exposed to peracetic-based airborne disinfectant was obtained. Conclusion This study demonstrates that the virucidal activity of airborne disinfectants can be tested on dried poliovirus. PMID:23587047

  16. Inactivation of an enterovirus by airborne disinfectants.

    PubMed

    Thevenin, Thomas; Lobert, Pierre-Emmanuel; Hober, Didier

    2013-04-15

    The activity of airborne disinfectants on bacteria, fungi and spores has been reported. However, the issue of the virucidal effect of disinfectants spread by fogging has not been studied thoroughly. A procedure has been developed to determine the virucidal activity of peracetic acid-based airborne disinfectants on a resistant non-enveloped virus poliovirus type 1. This virus was laid on a stainless carrier. The products were spread into the room by hot fogging at 55°C for 30 minutes at a concentration of 7.5 mL.m(-3). Poliovirus inoculum, supplemented with 5%, heat inactivated non fat dry organic milk, were applied into the middle of the stainless steel disc and were dried under the air flow of a class II biological safety cabinet at room temperature. The Viral preparations were recovered by using flocked swabs and were titered on Vero cells using the classical Spearman-Kärber CPE reading method, the results were expressed as TCID50.ml(-1). The infectious titer of dried poliovirus inocula was kept at 10(5) TCID50.mL(-1) up to 150 minutes at room temperature. Dried inocula exposed to airborne peracetic acid containing disinfectants were recovered at 60 and 120 minutes post-exposition and suspended in culture medium again. The cytotoxicity of disinfectant containing medium was eliminated through gel filtration columns. A 4 log reduction of infectious titer of dried poliovirus inocula exposed to peracetic-based airborne disinfectant was obtained. This study demonstrates that the virucidal activity of airborne disinfectants can be tested on dried poliovirus.

  17. Reduction of Acid-Fast and Non-Acid-Fast Bacteria by Point of Use Coagulation-Flocculation-Disinfection.

    PubMed

    Casanova, Lisa M; Sobsey, Mark D

    2015-11-13

    Point of use (POU) household water treatment is increasingly being adopted as a solution for access to safe water. Non-tuberculous Mycobacteria (NTM) are found in water, but there is little research on whether NTM survive POU treatment. Mycobacteria may be removed by multi-barrier treatment systems that combine processes such as coagulation, settling and disinfection. This work evaluated removal of a non-tuberculous Mycobacterium (Mycobaterium terrae) and a Gram-negative non-acid-fast environmental bacterium (Aeromonas hydrophila) by combined coagulation-flocculation disinfection POU treatment. Aeromonas hydrophila showed 7.7 log10 reduction in demand free buffer, 6.8 log10 in natural surface water, and 4 log10 reduction in fecally contaminated surface water. Turbidity after treatment was <1 NTU. There was almost no reduction in levels of viable M. terrae by coagulant-flocculant-disinfectant in natural water after 30 minutes. The lack of Mycobacteria reduction was similar for both combined coagulant-flocculant-disinfectant and hypochlorite alone. A POU coagulant-flocculant-disinfectant treatment effectively reduced A. hydrophila from natural surface waters but not Mycobacteria. These results reinforce previous findings that POU coagulation-flocculation-disinfection is effective against gram-negative enteric bacteria. POU treatment and safe storage interventions may need to take into account risks from viable NTM in treated stored water and consider alternative treatment processes to achieve NTM reductions.

  18. Reduction of Acid-Fast and Non-Acid-Fast Bacteria by Point of Use Coagulation-Flocculation-Disinfection

    PubMed Central

    Casanova, Lisa M.; Sobsey, Mark D.

    2015-01-01

    Point of use (POU) household water treatment is increasingly being adopted as a solution for access to safe water. Non-tuberculous Mycobacteria (NTM) are found in water, but there is little research on whether NTM survive POU treatment. Mycobacteria may be removed by multi-barrier treatment systems that combine processes such as coagulation, settling and disinfection. This work evaluated removal of a non-tuberculous Mycobacterium (Mycobaterium terrae) and a Gram-negative non-acid-fast environmental bacterium (Aeromonas hydrophila) by combined coagulation-flocculation disinfection POU treatment. Aeromonas hydrophila showed 7.7 log10 reduction in demand free buffer, 6.8 log10 in natural surface water, and 4 log10 reduction in fecally contaminated surface water. Turbidity after treatment was <1 NTU. There was almost no reduction in levels of viable M. terrae by coagulant-flocculant-disinfectant in natural water after 30 minutes. The lack of Mycobacteria reduction was similar for both combined coagulant-flocculant-disinfectant and hypochlorite alone. A POU coagulant-flocculant-disinfectant treatment effectively reduced A. hydrophila from natural surface waters but not Mycobacteria. These results reinforce previous findings that POU coagulation-flocculation-disinfection is effective against gram-negative enteric bacteria. POU treatment and safe storage interventions may need to take into account risks from viable NTM in treated stored water and consider alternative treatment processes to achieve NTM reductions. PMID:26580632

  19. Potential application of high pressure carbon dioxide in treated wastewater and water disinfection: Recent overview and further trends.

    PubMed

    Vo, Huy Thanh; Imai, Tsuyoshi; Ho, Truc Thanh; Dang, Thanh-Loc Thi; Hoang, Son Anh

    2015-10-01

    Recently emerging disadvantages in conventional disinfection have heightened the need for finding a new solution. Developments in the use of high pressure carbon dioxide for food preservation and sterilization have led to a renewed interest in its applicability in wastewater treatment and water disinfection. Pressurized CO2 is one of the most investigated methods of antibacterial treatment and has been used extensively for decades to inhibit pathogens in dried food and liquid products. This study reviews the literature concerning the utility of CO2 as a disinfecting agent, and the pathogen inactivation mechanism of CO2 treatment is evaluated based on all available research. In this paper, it will be argued that the successful application and high effectiveness of CO2 treatment in liquid foods open a potential opportunity for its use in wastewater treatment and water disinfection. The findings from models with different operating conditions (pressure, temperature, microorganism, water content, media …) suggest that most microorganisms are successfully inhibited under CO2 treatment. It will also be shown that the bacterial deaths under CO2 treatment can be explained by many different mechanisms. Moreover, the findings in this study can help to address the recently emerging problems in water disinfection, such as disinfection by-products (resulting from chlorination or ozone treatment).

  20. Efficacy of microwaves and chlorhexidine for disinfection of pacifiers and toothbrushes: an in vitro study.

    PubMed

    Chamele, Jay; Bhat, Chetan; Saraf, Tanvi; Jadhav, Abhijeet; Beg, Aumir; Jagtap, Chetana; Ubeja, Ritu; Patil, Padmeshwari

    2012-09-01

    The purpose of this study was to evaluate, in vitro, the contamination of toothbrushes and pacifiers by Streptococcus mutans, and the efficacy of microwave and chlorhexidine for their disinfection. Sixty pacifiers and 60 toothbrushes were contaminated with S. mutans and then divided into groups according to the disinfection protocol: Group 1-chlorhexidine solution; group 2-microwave sterilization; and group 3-sterile tap water. The devices were evaluated microbiologically after disinfection for the survival of S. mutans colonies and were examined. The results were analyzed statistically by ANOVA and Turkey test. The results of both types of evaluation showed a large number of S. mutans colonies after spraying with sterile tap water, and chlorhexidine spraying and microwaving were effective in eliminating colonies. Groups 1 and 2 were statistically similar to each other (p > 0.05) and differed significantly from group 3 (p < 0.05). The 0.12% chlorhexidine solution spray and 7 minutes of microwave irradiation were almost equally effective for disinfection of pacifiers and toothbrushes.